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Chinju, South Korea

Gyeongsang National University is a national university governed under the ministry of education of Republic of Korea government and located in Jinju, South Gyeongsang Province and represents the South Gyeongsang Province of South Korea as one of 10 Flagship Korean National Universities along with Cheju National University, Chonbuk National University, Chonnam National University, Chungnam National University, Chungbuk National University, Kangwon National University, Kyungpook National University, Pusan National University, and Seoul National University.Gyoengsang National University has twelve colleges including arts, social science, natural science, engineering, agriculture and life science, management, veterinary, education, nursing, and medicine and eight graduate schools including medicine and public health, business administration, education, aerospace, industry etc. Other institutions with the university are the university library, the university museum, student center, university newspaper and broadcasting center, publishing company, institute for education of science talented, Korean language cultural center and so on. The current statistics of Gyeongsang National University shows that it has 1,681 academic staffs including 808 full-time professors, 361 administrative staffs and 24,502 students including undergraduate and graduate students enrolled. The university has three campuses and two of these are located in Jinju, South Gyeongsang Province and the other is located in Tongyeong. The main campus is located at Gajwa in the city of Jinju, Chilam campus, Jinju has the college of medicine, and Tongyeong campus, an hour from Jinju by car, has the college of Marine Science.The motto of Gyeongsang National University is Pioneer and it states that the eyes of pioneers see far beyond the present to the future. The history of the university begun as Jinju Agricultural College founded in Jinju in 1948, in 1968, accredited as national college and in 1972, renamed as Gyeongsang National College. In 1980, it was accredited as national university by the ministry of education and renamed as Gyeongsang National University. For more than 60 years since its foundation, Gyeongsang National University has been educating talented students who have served not only for local community but also for national prosperity by leading them to be bigger asset in many places such as communities, industries, businesses and so on around the country and the world.Gyeongsang National University is well known for many achievements in applied life science along with biochemistry, agricultural science, and veterinary. One of these is that the researchers at the university discovered a way to make cloned Turkish Angora cats glow red when exposed to ultraviolet light in 2007 and many alumni in these fields are working as researchers and professionals in research institutions and universities around the world. In present, the university has made its highly competitive fields of study broad to mechanical and aerospace systems engineering and new nano-materials engineering. In addition, Gyeongsang National University has made achievements in humanities and in sociology, two fields which lay the foundation for human ethics. Beside this, Gyeongsang National University is proud to have the college of Education in where great middle school teachers are educated to take responsibility for education of Republic of Korea, the college of Veterinary Medicine in where international veterinarians are trained, and the College of Marine Science to pioneer the studies of the ocean in the twenty first century. The university keeps moving on to provide advanced international education in Republic of Korea by successfully partnering in international campuses in Incheon as well as Busan-Jinhae Free Economic Zones.The Graduate School of Medicine and Public Health at Gyeongsang National University is unique medical training and research institution in South Gyeongsang Province and plans are being made with Gyeongsang National University Hospital to open a specialized medical center in the city of Changwon as the second Gyeongsang National University hospital in 2013. Gyeongsang National University Hospital opened with 419 beds in 1987 as the university hospital of Gyeongsang National University and is located next to the college of medicine in Chilam campus and has provided health care service with quality for more than 25 years and grown to a general and multispecialty medical hospital with 950 beds operating with specialty centers such as the local cancer center opened as the first local cancer center of its kinds in the country and rheumatoid arthritis center. Wikipedia.

Koh P.-O.,Gyeongsang National University
Neuroscience Letters | Year: 2014

Estradiol plays a neuroprotective role against focal cerebral ischemia. Parvalbumin is an intracellular Ca2+-binding protein. It exerts a neuroprotective effect against cytotoxic Ca2+ overload. This study investigated whether estradiol modulates parvalbumin expression in focal cerebral ischemia and glutamate-induced neuronal cell death. Adult female rats were ovariectomied and treated with vehicle or estradiol prior to middle cerebral artery occlusion (MCAO). The cerebral cortex was collected 24h after MCAO. A proteomics approach showed a decrease of parvalbumin in MCAO-operated animals, while estradiol prevented the MCAO-induced decrease in parvalbumin. Reverse transcription-PCR and Western blot analyses confirmed that estradiol treatment attenuated the MCAO-induced decrease in parvalbumin levels. The results of immunohistochemical staining showed that the number of parvalbumin-positive cells decreased in MCAO-operated animals, and estradiol prevented the MCAO-induced decrease in parvalbumin-positive cells. In cultured hippocampal cells, glutamate exposure raised the intracellular Ca2+ concentration, while estradiol treatment attenuated this increase. Moreover, estradiol prevented the decrease in parvalbumin induced by glutamate toxicity. These findings suggest that estradiol exerts a neuroprotective effect by preventing the MCAO-induced decrease of parvalbumin and by regulating intracellular Ca2+ levels. © 2014 Elsevier Ireland Ltd. Source

Low P.A.,Mayo Medical School | Tomalia V.A.,Mayo Medical School | Park K.-J.,Gyeongsang National University
Journal of Clinical Neurology (Korea) | Year: 2013

Modern autonomic function tests can non-invasively evaluate the severity and distribution of autonomic failure. They have sufficient sensitivity to detect even subclinical dysautonomia. Standard laboratory testing evaluates cardiovagal, sudomotor and adrenergic autonomic functions. Cardiovagal function is typically evaluated by testing heart rate response to deep breathing at a defined rate and to the Valsalva maneuver. Sudomotor function can be evaluated with the quantitative sudomotor axon reflex test and the thermoregulatory sweat test. Adrenergic function is evaluated by the blood pressure and heart rate responses to the Valsalva maneuver and to head-up tilt. Tests are useful in defining the presence of autonomic failure, their natural history, and response to treatment. They can also define patterns of dysautonomia that are useful in helping the clinician diagnose certain autonomic conditions. For example, the tests are useful in the di-agnosis of the autonomic neuropathies and distal small fiber neuropathy. The autonomic neuropathies (such as those due to diabetes or amyloidosis) are characterized by severe generalized autonomic failure. Distal small fiber neuropathy is characterized by an absence of autonomic failure except for distal sudomotor failure. Selective autonomic failure (which only one system is affected) can be diagnosed by autonomic testing. An example is chronic idiopathic anhidrosis, where only sudomotor function is affected. Among the synucleinopathies, autonomic function tests can distinguish Parkinson's disease (PD) from multiple system atrophy (MSA). There is a gradation of autonomic failure. PD is characterized by mild autonomic failure and a length-dependent pattern of sudomotor involvement. MSA and pure autonomic failure have severe gen-eralized autonomic failure while DLB is intermediate. © 2013 Korean Neurological Association. Source

Koh P.-O.,Gyeongsang National University
Neuroscience Letters | Year: 2014

Estradiol has protective and reparative effects in neurodegenerative diseases. Hippocalcin is a neuronal calcium-sensor protein that acts as a calcium buffer to regulate the intracellular concentration of Ca2+. This study was investigated to elucidate whether estradiol regulates hippocalcin expression in a focal cerebral ischemia model and glutamate-treated neuronal cells. An ovariectomy was performed in adult female rats, and vehicle or estradiol was administered before middle cerebral artery occlusion (MCAO). Cerebral cortex tissues were collected at 24h after MCAO. A proteomic approach revealed that hippocalcin expression decreased in vehicle-treated animals with combined MCAO, while estradiol treatment attenuated this decrease. Reverse transcription-PCR and Western blot analyses also showed that estradiol administration prevented the MCAO injury-induced decrease in hippocalcin expression. In cultured hippocampal cells, glutamate exposure increased the intracellular Ca2+ concentration, which was rescued by the presence of estradiol. Moreover, glutamate toxicity decreased hippocalcin expression, whereas estradiol attenuated this decrease. Together, these findings suggest that estradiol has a neuroprotective function by regulating hippocalcin expression and intracellular Ca2+ levels in ischemic brain injury. © 2014 Elsevier Ireland Ltd. Source

Kam S.C.,Gyeongsang National University | Han D.H.,Sungkyunkwan University | Lee S.W.,Sungkyunkwan University
Journal of Sexual Medicine | Year: 2011

Introduction. Premature ejaculation (PE) is the most prevalent male ejaculation disorder. The premature ejaculation diagnostic tool (PEDT) was developed to systematically apply the DSM-IV-TR criteria in diagnostic PE. Aims. To evaluate the diagnostic value of the PEDT and its association with intravaginal ejaculatory latency time (IELT). Methods. (i) Korean validation of PEDT: data was collected from men interviewed by one of the two clinical experts, who made a diagnostic of present or absence of PE, using DSM-IV-TR criteria. A total of 103 patients with PE and 100 men without PE were enrolled into the study and requested to complete the PEDT; and (ii) The correlation between IELT and PEDT: 200 participants were enrolled and each participant was asked to make out PEDT. All participants were requested to measure IELT. Main Outcome Measures. Validity and reliability of the PEDT and its association with IELT. Results. The geometric mean IELT of the PE group was 115.37±78.14 seconds. The number of men reporting IELTs of <1, 1 to ≤2, and >2 minutes were 28 (28.6%), 29 (29.6%), and 41 (41.8%), respectively. The Cronbach's alpha score was calculated as 0.93, showing adequate internal consistency. The test-retest correlation coefficients of each item were higher than 0.72 and the correlation coefficients of the total score was 0.88. (P<0.001) Sensitivity and specificity analyses suggested a score of ≤8 indicated no PE, 9 and 10 probable PE, and ≥11 PE. The PEDT total score and IELT showed an adequate negative correlation. (ρ=-0.77, P<0.0001) also, the PEDT total score of the PE subgroup (IELT≤2 minutes) and IELT showed a negative correlation. (ρ=-0.6, P<0.0001) Conclusions. The PEDT was highly effective in detecting the presence of PE. The result of our study supports its validity as a diagnostic tool in the clinical setting. © 2010 International Society for Sexual Medicine. Source

Azadi Kenary H.,Yasouj University | Je Cho Y.,Gyeongsang National University
Computers and Mathematics with Applications | Year: 2011

In this paper, we prove the generalized HyersUlam stability of the following mixed additivequadratic functional equation: 2f(x+y2)+f(x-y2)+f(y-x2)= f(x)+f(y) in various spaces. © 2011 Elsevier Ltd. All rights reserved. Source

Paek S.-M.,Gyeongsang National University
Molecules | Year: 2015

Synthetic approaches to macrosphelide derivatives, based on medicinal chemistry, are summarized. This review contains conventional medicinal chemistry approaches, combinatorial chemistry, fluorous tagging techniques and affinity chromatography preparation. In addition, advances in their apoptosis-inducing activities are also included. © 2015 by the authors; licensee MDPI. Source

This study proposes a product data management (PDM) database that can support engineering change analysis (ECA). It can integrate ECA with the existing main product development process managed by PDM systems. Since engineering change (EC) history is a key EC data element that enables ECA, this study extends PDM databases to represent the EC history with existing entities for ECs and associated products and their product structures. To show the feasibility of the proposed PDM database, this study integrates a prototype PDM system with on-line analytical processing (OLAP) tools and a data mining module for ECA. It also applies the implemented tools to two typical ECA applications, EC evaluation and EC propagation problems. The illustrative application examples show that the proposed PDM database can support ECA through multidimensional data analysis with OLAP and data mining with association rules. © 2015 Elsevier B.V. All rights reserved. Source

Park P.,Gyeongsang National University
IEEE Communications Letters | Year: 2015

The traffic generation rate of the network used for cyber-physical systems is a crucial design parameter since it directly affects the stability of physical systems and the congestion level of communication systems. In this paper, we propose a novel modeling framework of the general wireless sensor and actuator networks of cyber-physical systems where the sensor-controller and controller-actuator sides communicate over a lossy network. The performance model is then used to derive the optimal traffic generation rate of sensors and controllers for minimizing the maximum outage probability of the stability constraint of the control systems while guaranteeing a schedulability constraint. The resulting problem is a non-linear optimization problem which allows to obtain the global optimum. An efficient approximation converts the proposed optimization problem into a linear programming problem. One interesting finding is that the optimal solution assigns higher traffic generate rate on the controller-actuator link compared to the one of the sensor-controller link since the actuating-link is more critical to guarantee the stability of the control systems. © 2015 IEEE. Source

Chen Z.,Wuhan University | Kang S.G.,Gyeongsang National University
International Journal of Distributed Sensor Networks | Year: 2014

A three-dimensional (3D) orthogonal frequency division multiplexing (OFDM) system with peak-to-average power ratio (PAPR) reduction method for the wireless sensor networks (WSNs) is presented. The transmit power of wireless nodes in an ad hoc network is strictly limited. Thus, high PAPR of the 3D OFDM system is a possible drawback when it is considered as a physical layer transmission scheme for the WSNs. Here, we propose an improved partial transmit sequence (PTS) technique to reduce PAPR of the OFDM system with 3D modulation formats. In the proposed algorithm, the components of 3D signals are assigned to different subblocks using a diagonal rule (DR), increasing randomness of the signals in the disjoint subblocks forcibly. As a result, the proposed method reduces PAPR of the 3D OFDM system significantly without increase in computational complexity. Hence, the proposed algorithm makes the 3D OFDM system be a possible candidate for a physical layer transmission scheme in future WSNs. © 2014 Zhenxing Chen and Seog Geun Kang. Source

Clinical experiences have suggested that East Asians show the higher risk of warfarin-related intracranial hemorrhage compared with Westerners. Therefore, different target of the International Normalized Ratio (INR) in East Asians (1.6-2.6) has been proposed and adapted in clinical practice. In terms with antiplatelet therapy, recent evidence has supported the concept of "therapeutic level of platelet reactivity" to balance clinical efficacy and safety in patients undergoing percutaneous coronary intervention (PCI) or those with acute coronary syndrome (ACS). In line with the warfarin experiences, multiple clinical and pharmacodynamic data from East Asians have shown their different therapeutic level of platelet reactivity following PCI or ACS (" East Asian Paradox"). Furthermore, like most cardiovascular drugs, P2Y12 receptor blockers have marked interethnic differences in the pharmacokinetics and pharmacodynamics. The currently performed clinical trials evaluating the clinical efficacy and safety of potent P2Y12 inhibitors mostly don't include enough number of East Asians to draw reliable conclusions. Therefore, dedicated research and guideline(s) for East Asians are required before we can apply Western recommendations for potent P2Y12 inhibitors in East Asian population. It is a time to consider the paradigm shift from "one-guideline-fits-all races"to "race-tailored antiplatelet therapy" in treating ACS patients. © Springer Science+Business Media 2014. Source

Kim S.-J.,Gyeongsang National University
BMC ophthalmology | Year: 2014

BACKGROUND: Phacolytic glaucoma is induced by lens protein or macrophages that have leaked through a macroscopically intact anterior lens capsule. Here, we report a case of phacolytic glaucoma with anterior lens capsule disruptions visualized by scanning electron microscopy (SEM).CASE PRESENTATION: A 71-year-old man was referred to our institute for increased intraocular pressure (IOP) in the right eye. Slit-lamp biomicroscopic examination revealed corneal edema, the presence of inflammatory cells and iridescent crystalline in the anterior chamber, and a hypermature cataract in the right eye. Despite treatment with topical glaucoma medication (0.15% brimonidine, 1% brinzolamide/0.5% timolol, and 0.03% bimatoprost) and systemic mannitol, his IOP remained uncontrolled. Light microscopy was used to examine the aqueous humor obtained via anterior chamber paracentesis and the anterior lens capsule obtained via intracapsular cataract extraction (ICCE), which revealed that the anterior lens capsule was intact. However, SEM revealed full-thickness disruptions in the anterior lens.CONCLUSION: This is the first reported case of phacolytic glaucoma with disruptions of the anterior lens capsule confirmed by SEM. Source

Park H.-D.,Joongbu University | Jun Y.-K.,Gyeongsang National University
International Journal of Software Engineering and its Applications | Year: 2013

Detecting data races is important in debugging shared memory parallel programs, because the races could exhibit unpredictable results in execution of programs. Unfortunately, previ- ous race detection techniques cannot guarantee that the detected accesses could be involved in the first races to occur in parallel programs which contain random synchronizations. This paper presents a monitoring algorithm which collects filtered key accesses of local thread blocks that are involved in races comparing with the latest filtered accesses of the other concurrent thread blocks in a particular execution of parallel programs. We discard all the accesses other than key accesses in a block to perform the race condition determination, which makes our algorithm more ecient in time and space. We alsodemonstrate the cor- rectness of our algorithm by showing at least one of the collected candidate accesses would be included in the actual first races. Source

Kim K.I.,Gyeongsang National University
International Journal of Software Engineering and its Applications | Year: 2013

Followed by our previous works, a study for performance evaluation of existing typical routing protocols for aircraft ad hoc networks is presented in this paper. The main objective of this evaluation is to figure out the impact of highspeed movement and spare deployment over well-known routing protocols with new mobility pattern for aircraft ad hoc networks. The chosen protocols are three major protocols according to general categorization, this is, AODV, DSDV, and GPSR.By analyzing the result of performance evaluation, we demonstrate the suitability of those in aircraft ad hoc networks in the terms of packet delivery ratio, end-to-end delay and control overhead and discuss further works in this research area. Finally, rough conclusion is made that it is necessary to develop new routing protocol based on DTN for aircraft adhoc networks. Source

Kim K.-I.,Gyeongsang National University
International Journal of Software Engineering and its Applications | Year: 2013

Recently aircraft ad hoc networks have received attention from many researchers since ad hoc network technology is expected to play a great role in communications between aircrafts. Due to large number of aircrafts as well as high bandwidth to meet emerging demands such as multimedia stream, ad hoc networks can be practical approach in this situation. However, since aircraft ad hoc networks possess significantly different properties to typical MANET or VANET, many research challenges remains unsolved yet. Among them, simulation study is one of key research area by providing simulation scenarios through simulator. Despite of importance, since current popular simulators do not provide the simulation environments for aircraft ad hoc networks, it is strongly required to extend the current simulators by adding several elements such as mobility model, type of node and so on. Based on above research needs, in this paper, we propose how to implementthe realistic mobility scenarios for aircraft ad hoc network. To design the relevant model, we implement new software which connects it to commercial flight simulator to generate mobility trace file. This file is converted to corresponding mobility file for each simulator. The software developed by .NET will be presented to validate its operation by diverse experiments. Source

Kim S.H.,Korea Research Institute of Bioscience and Biotechnology | Ahn Y.O.,Korea Research Institute of Bioscience and Biotechnology | Ahn M.-J.,Gyeongsang National University | Lee H.-S.,Korea Research Institute of Bioscience and Biotechnology | Kwak S.-S.,Korea Research Institute of Bioscience and Biotechnology
Phytochemistry | Year: 2012

Sweetpotato (Ipomoea batatas Lam.) is an important industrial crop and source of food that contains useful components, including antioxidants such as carotenoids. β-Carotene hydroxylase (CHY-β) is a key regulatory enzyme in the beta-beta-branch of carotenoid biosynthesis and it catalyzes hydroxylation into both β-carotene to β-cryptoxanthin and β-cryptoxanthin to zeaxanthin. To increase the β-carotene content of sweetpotato through the inhibition of further hydroxylation of β-carotene, the effects of silencing CHY-β in the carotenoid biosynthetic pathway were evaluated. A partial cDNA encoding CHY-β was cloned from the storage roots of orange-fleshed sweetpotato (cv. Shinhwangmi) to generate an RNA interference-IbCHY-β construct. This construct was introduced into cultured cells of white-fleshed sweetpotato (cv. Yulmi). Reverse transcription- polymerase chain reaction analysis confirmed the successful suppression of IbCHY-β gene expression in transgenic cultured cells. The expression level of phytoene synthase and lycopene β-cyclase increased, whereas the expression of other genes showed no detectable change. Down-regulation of IbCHY-β gene expression changed the composition and levels of carotenoids between non-transgenic (NT) and transgenic cells. In transgenic line #7, the total carotenoid content reached a maximum of 117 μg/g dry weight, of which β-carotene measured 34.43 μg/g dry weight. In addition, IbCHY-β-silenced calli showed elevated β-cryptoxanthin and zeaxanthin contents as well as high transcript level P450 gene. The 2,2-diphenyl-1- picrylhydrazyl radical scavenging activity (DPPH) in transgenic cells was more than twice that in NT cells. RNA-IbCHY-β calli increased abscisic acid (ABA) content, which was accompanied by enhanced tolerance to salt stress. In addition, the production of reactive oxygen species measured by 3,3′-diaminobenzidine (DAB) staining was significantly decreased in transgenic cultured cells under salt stress. Taken together, the present results indicate that down-regulation of IbCHY-β increased β-carotene contents and total carotenoids in transgenic plant cells and enhanced their antioxidant capacity. © 2011 Elsevier Ltd. All rights reserved. Source

Son S.,Gyeongsang National University
BMJ case reports | Year: 2014

Infections involving endovascular devices are rare and, to our knowledge, only three cases of infection with an inserted carotid stent have ever been reported. A 68-year-old man underwent carotid artery stenting (CAS) of the left proximal internal carotid artery. Two days after CAS the patient developed a high fever and investigation showed that the inserted carotid stent was infected. The infection could not be controlled despite adequate antibiotic therapy. Eventually a rupture of the carotid artery occurred and the patient underwent emergency resection of the left carotid bifurcation in addition to stent removal and reconstruction with a saphenous vein interposition graft. The patient recovered fully without any neurological sequelae. Source

Young S.,Korea University of Technology and Education | Nam T.-H.,Gyeongsang National University
Materials Research Bulletin | Year: 2014

Inhomogeneous deformation is one of the essential characters of shape memory alloy. Specimen is composed of many variants which have different strain. There exist a phase interface between two different phases and its mobility will depend on several factors such as curvature and orientation of the interface. The shape memory alloys exhibit hysteresis and one of the main reasons to cause hysteretic behavior is thought to be the internal inhomogeneity. It is thought that the phase interfaces display irregularities in the motion and the resultant state is metastable one which requires a very long relaxation time. In this work, spatially inhomogeneous frictional force to the volume change of the variants is assumed to account for the irregular behavior of the phase transformation. Its effect on the production of the macroscopic strain of a shape memory alloy is investigated using finite element calculation. Load-biased thermal cycling of a shape memory alloy is considered. The numerical result is compared with experimental data of Ti-44.5Ni-5Cu-0.5V (at.%) alloy. A better agreement is obtained for the experimental data when the inhomogeneous friction is assumed. © 2014 Elsevier Ltd. All rights reserved. Source

Park J.H.,Gyeongsang National University
Journal of Physics D: Applied Physics | Year: 2014

Quadrupole dielectrophoretic traps are widely used for the confinement of biological objects in various applications. This study shows the non-ponderomotive stability and random motion of micro-/nano-scale quadrupole dielectrophoretic traps. Distinguished from Paul traps, dielectrophoretic traps are unusually stable to the change of medium viscosity and it can be explained with the robustness of the stability island. Also, the present non-ponderomotive approach enables quantification of the random fluctuation rigorously ranging from the micro- to nanoscale. The pseudo-potential prediction works only when both the trap and particle are in the same lengthscale. Since the random motion determines the size of the virtual pore formed inside the trap, the magnitude of random fluctuation is a key parameter in trap optimization. In this study, the trap size and the oscillating frequency are adjusted to localize a particle within the nanometre area at the trap center. This paper provides an efficient method to optimize the essential factors in the design of nanoscale dielectrophoretic traps. © 2014 IOP Publishing Ltd. Source

Lee J.,Sungkyunkwan University | Park S.H.,Sungkyunkwan University | Chang H.-M.,University of Ulsan | Kim J.S.,Korea University | And 13 more authors.
The Lancet Oncology | Year: 2012

Background: Combination chemotherapy with gemcitabine and a platinum-based agent is regarded as a standard treatment for patients with advanced biliary-tract cancer. Results of phase 2 trials of single-agent erlotinib in biliary-tract cancer and of gemcitabine plus erlotinib in pancreatic cancer have shown modest benefits. Therefore, we aimed to investigate the efficacy of gemcitabine and oxaliplatin plus erlotinib versus chemotherapy alone for advanced biliary-tract cancer. Methods: In this open label, randomised, phase 3 trial, we randomly assigned patients (in a 1:1 ratio) with metastatic biliary-tract cancer (cholangiocarcinoma, gallbladder cancer, or ampulla of Vater cancer) to receive either first-line treatment with chemotherapy alone (gemcitabine 1000 mg/m 2 on day 1 and oxaliplatin 100 mg/m 2 on day 2) or chemotherapy plus erlotinib (100 mg daily). Treatment was repeated every 2 weeks until disease progression or unacceptable toxic effects. Randomisation was done centrally (stratified by participating centre and presence of measurable lesion). The primary endpoint was progression-free survival. Analyses were by intention-to-treat. This study is registered with ClinicalTrials.gov, number NCT01149122. Findings: 133 patients were randomly assigned to the chemotherapy alone group and 135 to the chemotherapy plus erlotinib group. The groups were balanced except for a higher proportion of patients with cholangiocarcinoma in the group given erlotinib than in the chemotherapy alone group (96 [71%] patients vs 84 [63%]). Median progression-free survival was 4·2 months (95% CI 2·7-5·7) in the chemotherapy alone group and 5·8 months (95% CI 4·6-7·0) in the chemotherapy plus erlotinib group (hazard ratio [HR] 0·80, 95% CI 0·61-1·03; p=0·087). Significantly more patients had an objective response in the chemotherapy plus erlotinib group than in the chemotherapy alone group (40 patients vs 21 patients; p=0·005), but median overall survival was the same in both groups (9·5 months [95% CI 7·5-11·5] in the chemotherapy alone group and 9·5 months [7·6-11·4] in the chemotherapy plus erlotinib group; HR 0·93, 0·69-1·25; p=0·611). All-cause deaths within 30 days of random assignment occurred in one (1%) of the patients in the chemotherapy alone group and in four (3%) of those in the chemotherapy plus erlotinib group. The most common grade 3-4 adverse event was febrile neutropenia (eight [6%] patients in the chemotherapy alone group and six [4%] in the chemotherapy plus erlotinib group). No patient died of treatment-related causes during the study. Subgroup analyses by primary site of disease showed that for patients with cholangiocarcinoma, the addition of erlotinib to chemotherapy significantly prolonged median progression-free survival (5·9 months [95% CI 4·7-7·1] for chemotherapy plus erlotinib vs 3·0 months [1·1-4·9] for chemotherapy alone; HR 0·73, 95% CI 0·53-1·00; p=0·049). Interpretation: Although no significant difference in progression-free survival was noted between groups, the addition of erlotinib to gemcitabine and oxaliplatin showed antitumour activity and might be a treatment option for patients with cholangiocarcinoma. Funding: None. © 2012 Elsevier Ltd. Source

Jeong Y.N.,Chonnam National University | Choi M.Y.,Gyeongsang National University | Choi H.C.,Chonnam National University
Electrochimica Acta | Year: 2012

Pt- and Pd-decorated carbon nanotubes (CNTs) have been prepared by diimide-activated amidation, an approach that avoids the harmful products of conventional SOCl 2 treatment. In this study, N,N′- dicyclohexylcarbodiimide (DCC) was used as a coupling agent for the formation of an amide linkage. According to ICP measurements, the resulting materials consist of 7.1 wt.% loaded Pt and 8.6 wt.% loaded Pd. The TEM images show that size-similar and quasi-spherical nanoparticles are highly dispersed along the entire CNT walls. The prepared Pt-CNT exhibited an especially high oxidation current toward methanol, formic acid, and formaldehyde compared with that of the pristine CNT and a Pt/CNT mixture (10 wt.% Pt). Furthermore, the Pd-CNT displayed higher activity toward H 2O 2 reduction than that of the reference systems. The better catalytic activities can be explained by the high electrochemically active surface area that resulted from the smaller size and excellent dispersion of metal nanoparticles on CNT. These results demonstrate the DCC-activated amidation to be a very effective and useful way to tune size and disperse metal species in metal-decorated CNTs, markedly improving their catalytic activity. © 2011 Elsevier Ltd. All rights reserved. Source

Chin Y.-W.,Dongguk University | Han S.-Y.,Gyeongsang National University
Expert Opinion on Therapeutic Patents | Year: 2015

Introduction: As epigenetic modulators, histone demethylases can be a therapeutic target in the area of oncology. KDM4 subfamily proteins are histone demethylases with a Jumonji domain. The subfamily consists of five functional members: KDM4A, KDM4B, KDM4C, KDM4D, and KDM4E. The role of the KDM4 subfamily proteins is reported in oncogenesis, and their overexpression in various tumor types is observed. Small molecule inhibitors for KDM4 proteins have great potential in anti-cancer therapy. Areas covered: A comprehensive review of the patents for KDM4 inhibitors is provided in this paper. Small molecule structural information and pharmacological effects are presented in the content. Expert opinion: The status of KDM4 inhibitor development is still in the early stages with small numbers of patents and journal articles. Future KDM4 inhibitor development should focus on obtaining selectivity between KDM4 subtypes, development of small molecules with in vivo activity, and extension of the therapeutic area of KDM4 inhibitors other than use in cancer therapy. © 2015 Informa UK, Ltd. Source

Hong J.,Korea Advanced Institute of Science and Technology | Jeong S.,Gyeongsang National University | Hahn M.,Korea Advanced Institute of Science and Technology
IEEE Transactions on Consumer Electronics | Year: 2013

Speech recognition for intelligent TVs is not easy mainly because of the TV sound itself. Input signals for automatic speech recognition systems have a low SNR condition due to the sounds from the TV acoustic speakers near to the microphone array installed on a TV. In addition, spoken commands for TV control are usually given at a considerably far distance. This tends to cause reverberated command inputs easily corrupted by other environmental noises. To achieve successful speech recognition with the harsh inputs, a powerful noise reduction algorithm is proposed. It is a combined solution cascading Wiener filterbased acoustic echo suppression (AES) and adaptive beamforming. To obtain noise power for AES, reference noises are estimated by utilizing the input signals to the TV speakers. For evaluation, output SNRs and speech recognition rates were measured under various noisy conditions and the results of the proposed system showed significant improvements, especially for low SNR. © 2013 IEEE. Source

Das A.K.,Gyeongsang National University
Physical Chemistry Chemical Physics | Year: 2015

Monte Carlo simulations performed on multiple polymer chains have produced accurate relaxation modulus Gs(t) curves which match the experimental G(t) curves of polystyrene reasonably well, over a wide temperature range around the glass transition region. The inter-segmental interactions, defined in terms of ε∗ (well depth) and σ (monomer size), exert a strong influence on the modulus, the length scale and the relaxation time scale of the system. Judicious selection of these interaction parameters has enabled us to create the whole range of temperature dependence of the thermorheological complexity, from ΔT = 40°C to ΔT = 0°C. Near the glass transition temperature, the development of nonergodicity vis-à-vis a crowding effect in the system emerges naturally from the analysis of the G(t) line shapes. The entropic slow mode is well described by the Rouse theory and the energetic fast mode shifts to longer time scales, revealing the generic behavior of the thermorheological complexity. Typical Gs(t) curves, when partitioned into glassy and rubbery components, are shown to obey Inoue-Okamoto-Osaki's modified stress-optical rule, with different stress-optical coefficients for each component. Closer to the glass transition temperature, the distance of the closest monomer shows a considerable increase, suggesting a penetrable resistance to the approach of another monomer. The parameter σ represents the characteristic length scale of the system in the glassy region. The thermorheological complexity incorporates the dynamic length scale of structural relaxation, increasing with the decrease of temperature towards the glass transition point. © the Owner Societies 2015. Source

Ban T.-W.,Gyeongsang National University
IEICE Transactions on Communications | Year: 2014

Recently, small cell systems such as femto cell are being considered as a good alternative that can support the increasing demand for mobile data traffic because they can significantly enhance network capacity by increasing spatial reuse. In this paper, we analyze the coverage and capacity of a femto cell when it is deployed in a hotspot to reduce the traffic loads of neighboring macro base stations (BSs). Our analysis results show that the coverage and capacity of femto cell are seriously affected by surrounding signal environment and they can be greatly enhanced by adapting power allocation for channels to the surrounding environment. Thus, we propose an adaptive power partitioning scheme where power allocation for channels can be dynamically adjusted to suit the environment surrounding the femto cell. In addition, we numerically derive the optimal power allocation ratio for channels to optimize the performance of the femto cell in the proposed scheme. It is shown that the proposed scheme with the optimal channel power allocation significantly outperforms the conventional scheme with fixed power allocation for channels. © 2014 The Institute of Electronics, Information and Communication Engineers. Source

Zhan J.,Hubei University for Nationalities | Jun Y.B.,Gyeongsang National University | Kim H.S.,Hanyang University
Journal of Intelligent and Fuzzy Systems | Year: 2014

The notions of falling fuzzy (implicative, positive implicative and fantastic) filters of a BL-algebra are introduced based on the theory of falling shadows and fuzzy sets. The relations between fuzzy (implicative, positive implicative and fantastic) filters and falling fuzzy (implicative, positive implicative and fantastic) filters are provided. Finally, we apply the concept of falling fuzzy inference relations to BL-algebras and obtain some related results. © 2014 - IOS Press. Source

Do N.,Gyeongsang National University
International Journal of Computer Integrated Manufacturing | Year: 2014

Life-cycle-oriented technical services are product-centric customer supports that aim to maximise product performance over its life cycle. This article proposes an extended product data model that can specify technical services, taking into account the product design and manufacturing process supported as integrated product life-cycle data. This integration allows the proposed model to evaluate the cost or environmental effects of products from the view of the product life cycle. The model specifies the life-cycle-oriented technical services by extending the STEP PDM schema, a widely implemented international standard for product data management (PDM). It helps manufacturers to integrate their technical services with current product and process specifications by using their existing PDM systems. A design information system based on a commercial PDM system is implemented based on the proposed product data model, and a set of application examples illustrates the effectiveness of the model for specifying life-cycle-oriented technical services. © 2014 Copyright Taylor & Francis Group, LLC. Source

Kim K.H.,Gyeongsang National University
International Journal of Web and Grid Services | Year: 2013

Utility-based resource management is becoming an emerging issue as the utilisation of cluster resources in Grid computing is growing rapidly. In this paper, we provide a new Imprecise Computation (IC) application model for flexible reward-based Grid resource management. An application in the proposed model consists of multiple independent jobs, in which each job has two parts: mandatory part for the minimum quality and optional part for additional computations. This application model can be applied to QoS-related Grid applications and used in adaptive resource management. We also provide scheduling algorithms for resource allocation of the IC applications based on reward. The profitable optional execution time is analysed for both space-shared and time-shared scheduling policies. Simulation results show that the proposed schemes are beneficial to both users and resource providers in terms of application acceptance rate and total reward. Copyright © 2013 Inderscience Enterprises Ltd. Source

Eshaghi Gordji M.,Semnan University | Baghani H.,Semnan University | Cho Y.J.,Gyeongsang National University
Mathematical and Computer Modelling | Year: 2011

Following the definition of coupled fixed point [T. G. Bhaskar, V. Lakshmikantham, Fixed point theorems in partially ordered metric spaces and applications, Nonlinear Anal. 65 (2006) 1379-1393], we prove a coupled fixed point theorem for contractive mappings in partially complete intuitionistic fuzzy normed spaces. © 2011 Elsevier Ltd. Source

Bagchi S.,Gyeongsang National University
Computers and Electrical Engineering | Year: 2014

Scheduling and execution of remote processes are integral parts of designing grid and cloud computing systems, which aim to utilize the idle CPU and memory resources of a node. However, such execution tends to degrade the overall performance of a node through over-loading and delaying the execution of local processes. This paper proposes the Admission Control and Scheduling (ACS) algorithm for execution of remote processes in a node based on online estimation method. The experimental results illustrate that the algorithm successfully schedules a large set of CPU-bound and IO-bound remote processes without degrading overall performance of a node. The comparisons of CPU-utilization and memory-utilization of an idle node and a stable node executing remote processes show that, the average utilizations are enhanced by 26.65% and 24.5%, respectively. However, the ACS algorithm successfully maintains the load-balance in a node so that, the performance of the local processes remains unaffected. © 2013 Elsevier Ltd. All rights reserved. Source

Lee S.-I.,University of California at San Diego | Lee S.-I.,Gyeongsang National University | Boyle D.L.,University of California at San Diego | Berdeja A.,Isis Pharmaceuticals | Firestein G.S.,University of California at San Diego
Arthritis Research and Therapy | Year: 2012

Introduction: The c-Jun N-terminal kinase (JNK) is a key regulator of matrix metalloproteinase (MMP) and cytokine production in rheumatoid arthritis (RA) and JNK deficiency markedly protects mice in animal models of arthritis. Cytokine-induced JNK activation is strictly dependent on the mitogen-activated protein kinase kinase 7 (MKK7) in fibroblast-like synoviocytes (FLS). Therefore, we evaluated whether targeting MKK7 using anti-sense oligonucleotides (ASO) would decrease JNK activation and severity in K/BxN serum transfer arthritis.Methods: Three 2'-O-methoxyethyl chimeric ASOs for MKK7 and control ASO were injected intravenously in normal C57BL/6 mice. PBS, control ASO or MKK7 ASO was injected from Day -8 to Day 10 in the passive K/BxN model. Ankle histology was evaluated using a semi-quantitative scoring system. Expression of MKK7 and JNK pathways was evaluated by quantitative PCR and Western blot analysis.Results: MKK7 ASO decreased MKK7 mRNA and protein levels in ankles by about 40% in normal mice within three days. There was no effect of control ASO on MKK7 expression and MKK7 ASO did not affect MKK3, MKK4 or MKK6. Mice injected with MKK7 ASO had significantly less severe arthritis compared with control ASO (P < 0.01). Histologic evidence of synovial inflammation, bone erosion and cartilage damage was reduced in MKK7 ASO-treated mice (P < 0.01). MKK7 deficiency decreased phospho-JNK and phospho-c-Jun in ankle extracts (P < 0.05), but not phospho-MKK4. Interleukin-1beta (IL-1β), MMP3 and MMP13 gene expression in ankle joints were decreased by MKK7 ASO (P < 0.01).Conclusions: MKK7 plays a critical regulatory role in the JNK pathway in a murine model of arthritis. Targeting MKK7 rather than JNK could provide site and event specificity when treating synovitis. © 2012 Lee et al.; licensee BioMed Central Ltd. Source

Lee W.,Gyeongsang National University | Cho D.-H.,Korea Advanced Institute of Science and Technology
IEEE Transactions on Wireless Communications | Year: 2014

We compare the capacity of two most popular methods for acquiring the state of the spectrum in cognitive radio technology: geolocation-database-based schemes and spectrum-sensing-based schemes. For the comparison, we use a new Hidden Markov Chain based channel model, because recent measurements show that a conventional two-state model, which has been widely used, is not appropriate for modeling the behavior of channels in the cognitive environment. We also consider more generic cognitive environments in which each wireless system has its own licensed bands and uses unlicensed bands in addition to its licensed bands to increase its capacity. This type of wireless systems can comprise conventional cognitive radio systems by letting the number of licensed bands be zero. Moreover, we have derived the optimal number of unlicensed bands to be used for maximizing the capacity of wireless system by taking into account interference from neighboring wireless systems. Through simulations, we compare the capacity of wireless systems with two channel state acquisition schemes and show the counterbalancing relation between two schemes, which has never been investigated in previous works. To the best of our knowledge, this is the first work to compare the capacity of these two schemes for acquiring the state of the spectrum. © 2002-2012 IEEE. Source

Lee G.-M.,Gyeongsang National University | Ju Y.-H.,Doosan Heavy Industries and Construction | Park M.-S.,Korea Polytechnic University
International Journal of Precision Engineering and Manufacturing | Year: 2013

In this paper, the possibility of the development of a new kind of low frequency shaker was discussed. In order to prove the possibility, a series of tests was performed using a direct-made experimental setup which contains a metal plate, springs and varying dampers. The frequency of the harmonic force variation and damper variation was set as f1 and f2. The plate center displacement achieves a peak point in the frequency component f1 and the rotational displacement achieves a peak point in the frequency components f1 + f2 and f1 - f2. In the experiment, the damper variation changed due to the damping constant value and current magnitude. Meanwhile, research on the natural frequency of the rotational displacement will continue. The inference of the reason for absence of frequency component related to rotational displacement natural frequency fnr is that the MR damper shows non-linear phenomenon in this experiment. © 2013 Korean Society for Precision Engineering and Springer-Verlag Berlin Heidelberg. Source

Okoloko I.,Cape Peninsula University of Technology | Kim Y.,Gyeongsang National University
Systems and Control Letters | Year: 2014

In this paper, we consider a team of spacecraft which requires changing its orientation to a common attitude using a decentralized control scheme under a connected communication topology, while satisfying cone avoidance constraints due to blind celestial objects, plume impingement and so on. For this purpose, we first combine consensus theory and optimization theory to develop a quaternion-based attitude consensus protocol. Based on the communication graph at each time step, each spacecraft generates a guidance command or reference attitude trajectory by synthesizing a series of Laplacian-like matrix P(t), using semidefinite programming (SDP) which involves linear matrix inequalities (LMIs). It is analytically shown that this series of matrices P(t) is capable of collectively driving the initial attitudes to a common consensus attitude. For satisfying cone avoidance constraints, exclusion zones are then identified and expressed as LMIs. This identification of the exclusion zones gives rise to selecting safe waypoints from the reference attitude trajectory and then to passing through the selected waypoints while avoiding the exclusion zones via proper control inputs. This solution procedure is demonstrated via numerical simulations of coordinated attitude rendezvous and attitude formation acquisition of multiple spacecraft with cone avoidance manoeuvres. © 2014 Elsevier B.V. All rights reserved. Source

Jeong B.G.,Pusan National University | Kim B.C.,Pusan National University | Moon Y.H.,Gyeongsang National University | Eom I.K.,Pusan National University
Signal Processing | Year: 2014

In this paper, we present a noise parameter estimation method using a simplified signal-dependent noise model. The generic Poisson-Gaussian noise model is simplified to a Gaussian-Gaussian noise model. From the simplified noise model, we experimentally verify that the value obtained by the robust median estimator is almost the same as the mean of the noise standard deviation. Based on this property, the noise model parameters are estimated by the least square method. Simulation results show that the estimation performance using our proposed algorithm is compatible with the performance of the existing method. Our method can generate good parameter estimation results with reduced computational complexity. © 2013 Elsevier B.V. Source

Lee J.-H.,Gyeongsang National University
Transactions of the Korean Institute of Electrical Engineers | Year: 2014

In this paper, an alternative variable structure controller is designed for the point-to-point regulation control of uncertain general linear plants so that the output of plants can be controlled from an arbitrarily given initial point to an arbitrarily given reference point in the state space. By using the error between the steady state value of the output and an arbitrarily given reference point and those integral, a transformed integral sliding surface is defined, in advance, as the surface from an initial state to an arbitrarily given reference point without the reaching phase problems. A corresponding control input is suggested to satisfy the existence condition of the sliding mode on the preselected transformed integral sliding surface against matched uncertainties and disturbances. Therefore, the output controlled by the proposed controller is completely robust and identical to that of the preselected transformed integral sliding surface. Through an example, the effectiveness of the suggested controller is verified. Source

Yoo C.-H.,Chonbuk National University | Yeom J.-H.,Chonbuk National University | Heo J.-J.,Chonbuk National University | Song E.-K.,Chonbuk National University | And 2 more authors.
Scientific Reports | Year: 2014

Lipopolysaccharide (LPS), an endotoxin derived from gram-negative bacteria, promotes the secretion of proinflammatory cytokines and mediates endotoxemia through activation of mitogen activated protein kinases, NF-κB, and interferon regulatory factor-3. Silent information regulator transcript-1 (SIRT1), an NAD-dependent deacetylase, mediates NF-κB deacetylation, and inhibits its function. SIRT1 may affect LPS-mediated signaling pathways and endotoxemia. Here we demonstrate that SIRT1 blocks LPS-induced secretion of interleukin 6 and tumor necrosis factor α in murine macrophages, and protects against lethal endotoxic and septic shock in mice. We also demonstrate that interferon β increases SIRT1 expression by activating the Janus kinase - signal transducer and activator of transcription (JAK-STAT) pathway in mouse bone marrow derived macrophages. In vivo treatment of interferon β protects against lethal endotoxic and septic shock, which is abrogated by infection with dominant negative SIRT1-expressing adenovirus. Our work suggests that both SIRT1 and SIRT1-inducing cytokines are useful targets for treating patients with sepsis. © 2014, Nature Publishing Group. All rights reserved. Source

This study was conducted to determine the changes in the accumulation of dry weight (DW) and the distribution of carbohydrates in different parts of young persimmon (Diospyros kaki) as affected by various fruit-loads. The effects of such changes were monitored with regard to the abundance of new growth in the following year. On June 15, the fruit-load was adjusted to a leaf-fruit (L/F) ratio of 10, 20, and 30, and some trees were completely defruited. Between June 15 and November 11, the increase in DW was less in the defruited and more in the higher L/F-ratio trees. Among the various tree parts, the DW increased the most in the fruits during the same period. It was observed that the lower the L/F ratio, the more the DW in the fruits: the fruits accounted for 78.7% of the total DW in the 10-L/F, 57.6% in the 20-L/F, and 49.7% in the 30-L/F ratio trees. In contrast, as the L/F ratio increased, the DW distribution to the roots increased to 3% in the 10-L/F, 13% in the 20-L/F, and 26% in the 30-L/F ratio trees and 61% in the defruited trees. During this period, carbohydrates were distributed mostly to the fruits, but as the L/F ratio decreased, their distribution to permanent tree parts decreased. The distribution of soluble sugars and starch to the permanent parts was 1% and 14% in the 10-L/F, 3% and 48% in the 20-L/F, 9% and 57% in the 30-L/F ratio trees, and 71% and 93% in the defruited trees, respectively. Maintaining a lower L/F ratio resulted in a decrease in the shoot and fruit numbers in the following year: there were zero and four fruits in those trees with an L/F ratio of 10 and 20, respectively. The carbohydrates decreased in the roots of both the 30-L/F ratio trees and the defruited trees, whereas the defruited trees showed more new shoot growth in the following year. In the roots of the trees with the L/F ratio of 30, soluble sugars and starch decreased by 7.6. g and 1.8. g, respectively, during the spring growth, whereas, in the roots of the defruited trees soluble sugars and starch decreased by 33.3. g and 94.6. g, respectively. © 2011 Elsevier B.V. Source

Lei M.,Tsinghua University | Zhu C.,Tsinghua University | Liu Y.,Tsinghua University | Karthikeyan A.S.,Purdue University | And 5 more authors.
New Phytologist | Year: 2011

With the exception of root hair development, the role of the phytohormone ethylene is not clear in other aspects of plant responses to inorganic phosphate (Pi) starvation. The induction of AtPT2 was used as a marker to find novel signalling components involved in plant responses to Pi starvation. Using genetic and chemical approaches, we examined the role of ethylene in the regulation of plant responses to Pi starvation. hps2, an Arabidopsis mutant with enhanced sensitivity to Pi starvation, was identified and found to be a new allele of CTR1 that is a key negative regulator of ethylene responses. 1-aminocyclopropane-1-carboxylic acid (ACC), the precursor of ethylene, increases plant sensitivity to Pi starvation, whereas the ethylene perception inhibitor Ag+ suppresses this response. The Pi starvation-induced gene expression and acid phosphatase activity are also enhanced in the hps2 mutant, but suppressed in the ethylene-insensitive mutant ein2-5. By contrast, we found that ethylene signalling plays a negative role in Pi starvation-induced anthocyanin production. These findings extend the roles of ethylene in the regulation of plant responses to Pi starvation and will help us to gain a better understanding of the molecular mechanism underlying these responses. © 2010 The Authors. New Phytologist © 2010 New Phytologist Trust. Source

Gwak W.S.,Gyeongsang National University | Nakayama K.,Kyoto University
Fisheries Science | Year: 2011

To investigate the extent of genetic differentiation among wild populations of the Pacific cod Gadus macrocephalus, we have examined genetic polymorphism at five locations within Korean waters [Boryeong in the West Sea (WC-BR); Jinhae Bay in the South Sea (SC-JH); Jumunjin (EC-JM), Jukbyeon (EC-JB), and Bangeojin (EC-BJ) off the eastern coast of Korea] using mitochondrial DNA (mtDNA) control region and microsatellite DNA (msDNA) markers. Nucleotide sequence analysis of 584 bp in the variable portion of the 5′ end of the mtDNA control region revealed 27 variable nucleotide sites among 184 individuals, which defined eight, three, and 11 haplotypes in the western, southern, and eastern coast populations, respectively. The mtDNA analysis revealed a low variability but significant local differentiation among populations from these three areas within Korean waters. msDNA analysis also revealed moderate polymorphism in the wild populations, with a mean of 13. 8-22.6 alleles per locus for the five msDNA markers and observed (and expected) heterozygosities of 0.755 (0.825) for the WC-BR, 0.793 (0.810) for the SC-JH, 0.920 (0.905) for the EC-BJ, 0.783 (0.865) for the EC-JB, and 0.804 (0.812) for the EC-JM populations. Analysis of msDNA loci indicated that Pacific cod sampled at the WC-BR, SC-JH, and EC-JB sites belong to genetically distinct populations. However, no significant difference was found between the Pacific cod population from SC-JH and that from EC-BJ. Consequently, three genetically distinct populations, namely, WC-BR, SC-JH and EC-BJ, and EC-JB, were identified using msDNA analysis. These results indicate that genetically distinct populations of Pacific cod are present in Korean coastal waters where spawning aggregations occur. © 2011 The Japanese Society of Fisheries Science. Source

Kwon M.,Gyeongsang National University | Shing P.B.,University of California at San Diego | Mallare C.,HNTB | Restrepo J.,University of California at San Diego
Earthquake Spectra | Year: 2011

This paper presents a study of the seismic resistance of two reinforced concrete cap beams in existing elevated guideway structures constructed in the 1960s. One beam has a regular configuration and the other has an irregular configuration. For each beam type, a half-scale model was designed, constructed, and tested. The irregular beam tested had a larger depth and a higher quantity of main longitudinal steel. While the regular beam had spiral confinement extending into the beam-to-column joint, the irregular beam did not. The beams were subjected to simultaneous bending, shear, and torsion in the tests, with the torsion induced by the vertical eccentricity of the horizontal load exerted at the top face of the beams. The test results underscore the importance of confinement steel in the beam-to- column joint of a cap beam and the critical role of the longitudinal reinforcement in the beams for torsional resistance. A numerical parametric study has been conducted with nonlinear finite element and strut-and-tie models, which have been validated with the experimental results. The study has indicated that the seismic load resistance of a cap beam can decrease with a reduced gravity load, which is an important consideration for design. © 2011, Earthquake Engineering Research Institute. Source

Telke A.A.,Gyeongsang National University | Ghodake G.S.,Kyungpook National University | Kalyani D.C.,Konkuk University | Dhanve R.S.,National Taipei University of Technology | Govindwar S.P.,Shivaji University
Bioresource Technology | Year: 2011

Bacillus sp. ADR secretes an extracellular laccase in nutrient broth, and this enzyme was purified up to 56-fold using acetone precipitation and DEAE-cellulose anion exchange chromatography. The molecular weight of purified laccase was estimated to be 66. kDa using sodium dodecyl sulfate polyacrylamide gel electrophoresis. The purified laccase oxidized 2,6-dimethoxy phenol, o-tolidine, hydroquinone, l-DOPA and guaiacol. The optimum pH for oxidation of o-tolidine, 2,6-dimethoxy phenol and guaiacol were 3.0, 4.0 and 5.0, respectively. The purified laccase contained 2.7. mol/mol of copper. The laccase was stable up to 40 °C and within the pH range of 7.0-9.0. Well-known inhibitors of multicopper oxidases such as, sodium azide, l-cysteine and dithiothreitol showed significant inhibition of laccase activity. The purified enzyme decolorized structurally different azo dyes with variable decolorization rates and efficiencies of 68-90%. This study is useful for understanding the precise use of Bacillus sp. ADR in the decolorization of textile dyes containing industrial wastewater. © 2010 Elsevier Ltd. Source

Ikeda M.,Toho University | Matsu-Ura A.,Toho University | Kuwahara S.,Toho University | Lee S.S.,Gyeongsang National University | Habata Y.,Toho University
Organic Letters | Year: 2012

The first example of a new Hg 2+-sensing system based on the structures of complexes is reported. The system uses a combination of a new chiral bidentate ligand and CD spectroscopy. Significant CD spectral changes are observed when Hg 2+ is added, whereas no CD spectral changes are observed in the cases of Li +, Na +, K +, Mg 2+, Ca 2+, Mn 2+, Fe 2+, Co 2+, Ni 2+, Cu 2+, Zn 2+, Rb +, Ag +, Cd 2+, La 3+, Gd 3+, and Pb 2+. © 2012 American Chemical Society. Source

Kim K.H.,Yonsei University | Kim J.Y.,Yonsei University | Kim M.O.,Gyeongsang National University | Moon M.H.,Yonsei University
Journal of Proteomics | Year: 2012

This study demonstrates the use of on-line isoelectric focusing/asymmetrical flow field-flow fractionation (IEF-AF4), a non-gel based high speed two dimensional (isoelectric point and hydrodynamic diameter) protein separation device used for the isolation/separation of phosphoproteins. IEF-AF4 performance was evaluated by first fractionating α-casein molecules at different pIs and sizes. Collected proteins were analyzed by nanoflow liquid chromatography-tandem mass spectrometry (nLC-MS n) to determine various isoforms of the phosphopeptides as well as the relative ratio of phosphorylated and unmodified peptides. A narrow pH cut (δpH=0.5) of carrier ampholyte was used in IEF-AF4 to finely resolve phosphoproteins by pI. When the channel lane of multilane AF4 became acidic, the relative ratio of phosphorylated to unmodified or less phosphorylated peptides increased. The current method was applied to prostate cancer cell lysates to demonstrate that IEF-AF4 can examine the relative abundances of specific phosphoproteins, known as biomarkers, in prostate cancer. While affinity-based enrichment methods remove unmodified peptides, IEF-AF4 offers intact phosphoprotein separation at the protein level without removing unmodified proteins. IEF-AF4 enables quantitative analysis without isotope labeling. © 2012 Elsevier B.V. Source

Limkatanyu S.,Prince of Songkla University | Damrongwiriyanupap N.,University of Phayao | Kwon M.,Gyeongsang National University | Ponbunyanon P.,Prince of Songkla University
ZAMM Zeitschrift fur Angewandte Mathematik und Mechanik | Year: 2015

In this paper, the exact element stiffness matrix for a beam on Winkler-Pasternak foundation and the fixed-end force vector due to a linearly distributed load are alternatively derived based on the virtual force principle. The exact element flexibility matrix is at the core of the derivation of the exact element stiffness matrix and is formulated based on the exact force interpolation functions. The virtual force principle is employed to reveal the governing differential compatibility equations as well as the associated end-boundary compatibility conditions. The exact force interpolation functions of the beam-foundation system are derived based on the analytical solution of the governing differential compatibility equations of the problem for all combinations of foundation parameters and beam rigidity. This feature is unique to this paper. The matrix virtual force equation is employed to obtain the exact element flexibility matrix using the exact force interpolation functions. The so-called "natural" element stiffness matrix is obtained by inverting the exact element flexibility matrix. Three numerical examples confirm the accuracy and the efficiency of the natural beam element on Winkler-Pasternak foundation and show the deficiency of the widely used Winkler foundation model. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Seo J.H.,Gyeongsang National University
The Korean journal of gastroenterology = Taehan Sohwagi Hakhoe chi | Year: 2013

Duodenal ulcers occur relatively frequently in adolescents, like in adults, and may relate to Helicobacter pylori infection and duodenal gastric metaplasia (DGM). This study investigated the association between H. pylori infection and DGM in healthy adults aged 20-29. Between 1995 and 2005, endoscopic biopsies of the duodenum, antrum and body were taken from healthy, young volunteers, who were first-year medical students, faculty staff, residents, and research assistants of Gyeongsang National University in Jinju, Korea. Urease tests were performed and the extent of DGM and histopathological grades according to the Updated Sydney System were determined. In total, 662 subjects were enrolled (429 males and 233 females). The median age was 22.3 years. The overall incidence of DGM was 11.5% but DGM was more frequent in males (15.4%) than in females (4.3%) (p<0.0001). While H. pylori positivity rates changed significantly during the 1995-2005 period (p<0.01), the incidences of DGM did not. DGM was observed in 7.2% and 14.9% of subjects who were and were not colonized with H. pylori, respectively. DGM was also associated with less severe chronic gastritis and the absence of active gastritis in both the antrum and body, and the absence of follicles in the antrum (p<0.05). These findings suggested that DGM is not rare in healthy young adults and is unrelated to gastric H. pylori infection. Source

Chung D.S.,Chung - Ang University | Kim Y.-H.,Gyeongsang National University | Lee J.-S.,Daegu Gyeongbuk Institute of Science and Technology
Nanotechnology | Year: 2014

We demonstrate an approach to enhance the photosensitivity of an organic single-crystal photodetector by combining it with a nanocrystal (NC) array. A systematic study of the dependence of the photodetector performance on illumination wavelength and light power together with the charge carrier mobility reveals that charge separation at the single-crystal/CdSe NC interface and subsequent electron trapping in the CdSe NCs generates effective photoconductive gain by hole circulation through the high-mobility single crystal. As a result, the responsivity and specific detectivity reached values up to 50 A W-1 and 2 × 109 cm Hz1/2 W-1, respectively. © 2014 IOP Publishing Ltd. Source

Lee T.,Gyeongsang National University | Modarres R.,INRS ETE | Ouarda T.B.M.J.,INRS ETE | Ouarda T.B.M.J.,Masdar Institute of Science and Technology
Hydrological Processes | Year: 2013

In recent decades, copula functions have been applied in bivariate drought duration and severity frequency analysis. Among several potential copulas, Clayton has been mostly used in drought analysis. In this research, we studied the influence of the tail shape of various copula functions (i.e. Gumbel, Frank, Clayton and Gaussian) on drought bivariate frequency analysis. The appropriateness of Clayton copula for the characterization of drought characteristics is also investigated. Drought data are extracted from standardized precipitation index time series for four stations in Canada (La Tuque and Grande Prairie) and Iran (Anzali and Zahedan). Both duration and severity data sets are positively skewed. Different marginal distributions were first fitted to drought duration and severity data. The gamma and exponential distributions were selected for drought duration and severity, respectively, according to the positive skewness and Kolmogorov-Smirnov test. The results of copula modelling show that the Clayton copula function is not an appropriate choice for the used data sets in the current study and does not give more drought risk information than an independent model for which the duration and severity dependence is not significant. The reason is that the dependence of two variables in the upper tail of Clayton copula is very weak and similar to the independent case, whereas the observed data in the transformed domain of cumulative density function show high association in the upper tail. Instead, the Frank and Gumbel copula functions show better performance than Clayton function for drought bivariate frequency analysis. © 2012 John Wiley & Sons, Ltd. Source

Kim Y.,Gyeongsang National University
International Journal of Mechanical Engineering Education | Year: 2015

Statics is the well-established first course in mechanics for first-year engineering students all over the world. For this reason, good learning modules (making use of computer animation, group-based projects, practical labs, internet, etc.) have been developed for teaching statics especially at education-oriented universities. It seems, however, that rarely found are 'in-class' demonstrations or 'hands-on' teaching methods for statics which turn out to be crucial for encouraging first-year students to become quickly engaged in mechanics. There is indeed a lot of evidence that students fully appreciate physical concepts right in the classroom via these hands-on teaching methods. In this paper, one such hands-on teaching method, so-called 'in-class demonstration, assignment and evaluation' (DAE, for short), is presented. DAE involves six exercises that can be immediately adopted in the classroom to clearly convey to students the major concepts arising in statics, such as equilibrium, centre of gravity, stability and friction. It is found that DAE can get approximately 94% of the students in class to engage in learning and reduce the percentage of low-motivation students by 7-11%. © The Author(s) 2015. Source

Lee M.,Korea Institute of Radiological and Medical Sciences | Lee H.-J.,Korea Institute of Radiological and Medical Sciences | Park K.H.,Gyeongsang National University | Lee Y.-S.,Korea Institute of Radiological and Medical Sciences
International Journal of Radiation Oncology Biology Physics | Year: 2010

Purpose: Previously, we reported that radiation-induced ST6 Gal I gene expression was responsible for an increase of integrin β1 sialylation. In this study, we have further investigated the function of radiation-mediated integrin β1 sialylation in colon cancer cells. Methods and Materials: We performed Western blotting and lectin affinity assay to analyze the expression and level of sialylated integrin β1. After exposure to ionizing radiation (IR), adhesion and migration of cells were measured by in vitro adhesion and migration assay. Results: IR increased sialylation of integrin β1 responsible for its increased protein stability and adhesion and migration of colon cancer cells. However, for cells with an N-glycosylation site mutant of integrin β1 located on the I-like domain (Mu3), these effects were dramatically inhibited. In addition, integrin β1-mediated radioresistance was not observed in cells containing this mutant. When sialylation of integrin β1 was targeted with a sulfonamide chalcone compound, inhibition of radiation-induced sialylation of integrin β1 and inhibition of radiation-induced adhesion and migration occurred. Conclusion: The increase of integrin β1 sialylation by ST6 Gal I is critically involved in radiation-mediated adhesion and migration of colon cancer cells. From these findings, integrin β1 sialylation may be a novel target for overcoming radiation-induced survival, especially radiation-induced adhesion and migration. © 2010 Elsevier Inc. All rights reserved. Source

Ko J.-Y.,Jeju National University | Lee J.-H.,Jeju National University | Samarakoon K.,Jeju National University | Kim J.-S.,Gyeongsang National University | Jeon Y.-J.,Jeju National University
Food and Chemical Toxicology | Year: 2013

We investigated the effects of bioactive-peptides from hydrolysates of flounder fish muscle (FFM) on antioxidant activity. The hydrolysates were prepared by enzymatic reactions of FFM using eight commercial proteases such as papain, pepsin, trypsin, neutrase, alcalase, kojizyme, protamex, and α-chymotrypsin. The α-chymotrypsin hydrolysate showed the strongest antioxidant activity among the eight enzymatic hydrolysates. Further separation of the α-chymotrypsin hydrolysate was performed by ultrafiltration, gel filtration, and reverse-phase high performance liquid chromatography. Consequently, two novel peptides with high antioxidant activity were purified, and their amino acid sequences were determined (Val-Cys-Ser-Val [VCSV] and Cys-Ala-Ala-Pro [CAAP], respectively). The two peptides showed good scavenging activity against the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical (IC50 values, 111.32 and 26.89μM, respectively) and high cytoprotective activities against 2,2-azobis-(2-amidino-propane) dihydrochloride (AAPH) without cytotoxicity and scavenged total reactive oxygen species in Vero cells. In particular, apoptotic bodies produced by AAPH dose-dependently decreased following treatment with the CAAP peptide. These results revealed firstly the two peptides with strong antioxidative effects from FFM. © 2012 Elsevier Ltd. Source

Chung W.S.,Gyeongsang National University
Modern Physics Letters A | Year: 2016

Quantum mechanics in a noncommutative plane with both space noncommutativity and momentum noncommutativity is considered. For a general two-dimensional central field, we show that the theory can be perturbatively solved for large values of the space noncommutative parameter (Formula presented.) when the momentum noncommutative parameter (Formula presented.) is proportional to (Formula presented.). We obtain the expressions for the eigenstates and eigenvalues. We also discuss the more general noncommutative algebra which have the nonvanishing commutator for (Formula presented.) for different (Formula presented.), (Formula presented.). © 2016 World Scientific Publishing Company Source

Kang M.,University of Ulsan | Kim J.,University of Ulsan | Kim J.-M.,University of Ulsan | Tan A.C.C.,Queensland University of Technology | And 2 more authors.
IEEE Transactions on Power Electronics | Year: 2015

This paper proposes a highly reliable fault diagnosis approach for low-speed bearings. The proposed approach first extracts wavelet-based fault features that represent diverse symptoms of multiple low-speed bearing defects. The most useful fault features for diagnosis are then selected by utilizing a genetic algorithm (GA)-based kernel discriminative feature analysis cooperating with one-against-all multicategory support vector machines (OAA MCSVMs). Finally, each support vector machine is individually trained with its own feature vector that includes the most discriminative fault features, offering the highest classification performance. In this study, the effectiveness of the proposed GA-based kernel discriminative feature analysis and the classification ability of individually trained OAA MCSVMs are addressed in terms of average classification accuracy. In addition, the proposed GA-based kernel discriminative feature analysis is compared with four other state-of-the-art feature analysis approaches. Experimental results indicate that the proposed approach is superior to other feature analysis methodologies, yielding an average classification accuracy of 98.06% and 94.49% under rotational speeds of 50 revolutions-per-minute (RPM) and 80 RPM, respectively. Furthermore, the individually trained MCSVMs with their own optimal fault features based on the proposed GA-based kernel discriminative feature analysis outperform the standard OAA MCSVMs, showing an average accuracy of 98.66% and 95.01% for bearings under rotational speeds of 50 RPM and 80 RPM, respectively. © 2014 IEEE. Source

Kuyanov-Prozument K.,University of Southern California | Kuyanov-Prozument K.,Massachusetts Institute of Technology | Choi M.Y.,Gyeongsang National University | Vilesov A.F.,University of Southern California
Journal of Chemical Physics | Year: 2010

Water dimers have been assembled in He droplets and studied by infrared laser depletion spectroscopy. All four OH stretching bands of the dimer have been identified in the spectral range 3590-3800 cm-1. Infrared intensities of the bands are also reported. The results are compared with previous measurements and theoretical calculations. © 2010 American Institute of Physics. Source

Kim S.H.,Korea Research Institute of Bioscience and Biotechnology | Kim Y.-H.,Korea Research Institute of Bioscience and Biotechnology | Ahn Y.O.,Korea Research Institute of Bioscience and Biotechnology | Ahn M.-J.,Gyeongsang National University | And 3 more authors.
Physiologia Plantarum | Year: 2013

Lycopene ε{lunate}-cyclase (LCY-ε{lunate}) is involved in the first step of the α-branch synthesis pathway of carotenoids from lycopene in plants. In this study, to enhance carotenoid synthesis via the β-branch-specific pathway [which yields β-carotene and abscisic acid (ABA)] in sweetpotato, the expression of IbLCY-ε{lunate} was downregulated by RNAi (RNA interference) technology. The RNAi-IbLCY-ε{lunate} vector was constructed using a partial cDNA of sweetpotato LCY-ε{lunate} isolated from the storage root and introduced into cultured sweetpotato cells by Agrobacterium-mediated transformation. Both semi-quantitative Reverse transcription polymerase chain reaction (RT-PCR) of carotenoid biosynthesis genes and high-performance liquid chromatography (HPLC) analysis of the metabolites in transgenic calli, in which the LCY-ε{lunate} gene was silenced, showed the activation of β-branch carotenoids and its related genes. In the transgenic calli, the β-carotene content was approximately 21-fold higher than in control calli, whereas the lutein content of the transgenic calli was reduced to levels undetectable by HPLC. Similarly, expression of the RNAi-IbLCY-ε{lunate} transgene resulted in a twofold increase in ABA content compared to control calli. The transgenic calli showed significant tolerance of 200 mM NaCl. Furthermore, both the β-branch carotenoids content and the expression levels of various branch-specific genes were higher under salt stress than in control calli. These results suggest that, in sweetpotato, downregulation of the ε{lunate}-cyclization of lycopene increases carotenoid synthesis via the β-branch-specific pathway and may positively regulate cellular defenses against salt-mediated oxidative stress. © Physiologia Plantarum 2012. Source

Myong R.S.,Gyeongsang National University
Physics of Fluids | Year: 2014

The high Mach number shock structure singularity arising in moment equations of the Boltzmann equation was investigated. The source of the singularity is shown to be the unbalanced treatment between two high order kinematic and dissipation terms caused by the overreach of Maxwellian molecule assumption. In compressive gaseous flow, the high order stress-strain coupling term of quadratic nature will grow far faster than the strain term, resulting in an imbalance with the linear dissipation term and eventually a blow-up singularity in high thermal nonequilibrium. On the other hand, the singularity arising from unbalanced treatment does not occur in the case of velocity shear and expansion flows, since the high order effects are cancelled under the constraint of the free-molecular asymptotic behavior. As an alternative method to achieve the balanced treatment, Eu's generalized hydrodynamics, consistent with the second law of thermodynamics, was revisited. After introducing the canonical distribution function in exponential form and applying the cumulant expansion to the explicit calculation of the dissipation term, a natural platform suitable for the balanced treatment was derived. The resulting constitutive equation with the nonlinear factor was then shown to be well-posed for all regimes, effectively removing the high Mach number shock structure singularity. © 2014 AIP Publishing LLC. Source

Kwon O.-Y.,Gyeongsang National University | Park S.-P.,Kyungpook National University
Epilepsy and Behavior | Year: 2011

The quality of life (QOL) of individuals with well-controlled epilepsy (WCE) is often not considered. We therefore investigated predictors determining QOL in patients who had been seizure free at least 1. year on stable antiepileptic drug (AED) monotherapy. They were asked to complete self-report health questionnaires, including the Beck Depression Inventory (BDI), Adverse Event Profile (AEP), and Quality of Life in Epilepsy Inventory-31 (QOLIE-31). We looked for predictors of QOLIE-31 scores among the various demographic, socioeconomic, and clinical factors and BDI, and AEP scores. Depression symptoms were manifested by 18.7% of patients. People with depression symptoms were more likely to report adverse events than those without depression symptoms. The strongest predictor of QOL was BDI score, followed by AEP total score, years of education, and income. BDI score had 3.37 times the effect of AEP total score. In conclusion, QOL of patients with WCE is determined mainly by depressive symptoms. © 2011 Elsevier Inc. Source

Lee K.-C.,Gyeongsang National University
Journal of Nanoscience and Nanotechnology | Year: 2013

When polymer particles come into use, especially, for photonic crystal applications, their diameter, dispersivity, and refractive indices become very important. Poly(benzyl methacrylate) is known to be a kind of high refracive materials (n = 1.57) compared to poly(methyl methacrylate) (n = 1.49). Not many work was concerned for surfactant-free emulsion polymerization of benzyl methacrylate or its copolymerization using cationic initiators. Narrowly dispersed cationic poly(BMA-co-MMA) and PBMA latices were synthesized successfully by surfactant-free emulsion polymerization with AIBA. The influences of BMA/MMA ratio, BMA/MMA monomer and initiator concentrations, addition of DVB/EGDMA crosslink agent, and polymerization temperature on the kinetics and on the particle size and molecular weight were studied. Monodisperse cationic charged PBMA and poly(BMA-co-MMA) latices with particle diameters varying between 160~494 nm and polymer molecular weights of the order 1.25 × 104 to 7.55 × 104 g/mol were prepared. The rate of polymerization increased with increasing MMA concentration in BMA/MMA ratio, AIBA concentration, DVB crosslink agent, and polymerization temperature. The particle diameter increased with BMA concentration in BMA/MMA ratio, AIBA concentration, and BMA/MMA monomer concentration. The molecular weight increased with BMA concentration in BMA/MMA ratio and BMA/MMA monomer concentration. The glass transition temperature of the latex copolymers decreased with increasing amount of BMA from 375 K for PMMA to 321 K for PBMA. It was, thus, found that the particle diameter and rate of polymerization as well as the polymer molecular weight for surfactant-free emulsion polymerization of BMA and MMA can be controlled easily by controlling the BMA/MMA ratio, BMA/MMA monomer concentration, AIBA concentration, and polymerization temperature. © 2013 American Scientific Publishers. Source

Hur S.J.,Gyeongsang National University | Lim B.O.,Konkuk University | Decker E.A.,University of Massachusetts Amherst | McClements D.J.,University of Massachusetts Amherst
Food Chemistry | Year: 2011

In vitro digestion models are widely used to study the structural changes, digestibility, and release of food components under simulated gastrointestinal conditions. However, the results of in vitro digestion models are often different to those found using in vivo models because of the difficulties in accurately simulating the highly complex physicochemical and physiological events occurring in animal and human digestive tracts. This paper provides an overview of current trends in the development and utilisation of in vitro digestion models for foods, as well as information that can be used to develop improved digestion models. Our survey of in vitro digestion models found that the most predominant food samples tested were plants, meats, fish, dairy, and emulsion-based foods. The most frequently used biological molecules included in the digestion models were digestive enzymes (pancreatin, pepsin, trypsin, chymotrypsin, peptidase, α-amylase, and lipase), bile salts, and mucin. In all the in vitro digestion models surveyed, the digestion temperature was 37°C although varying types and concentrations of enzymes were utilised. With regard to digestion times, 2. h (the stomach, small intestine, and large intestine each) was predominantly employed. This survey enhances the understanding of in vitro digestion models and provides indications for the development of improved in vitro digestion models for foods or pharmaceuticals. © 2010 Elsevier Ltd. Source

Bagchi S.,Gyeongsang National University
Lecture Notes in Electrical Engineering | Year: 2014

The large scale loosely-coupled distributed systems such as, grid and cloud computing systems employ opportunistic execution mechanism of remote processes in order to utilize computing resources of idle nodes. The opportunistic admission and scheduling of remote processes at a node need to balance the enhanced resource utilization and the performance of local processes at the node. This paper proposes the design and implementation of a novel Admission Control and Scheduling (ACS) algorithm for opportunistic execution of remote processes in a distributed system based on online estimation method. The experimental results illustrate that the algorithm can schedule the CPU-bound and IO-bound remote processes without degrading overall performance of a node. The CPU-utilization and memory-utilization of a node are enhanced by 26.65 and 24.5 % respectively on the average without degrading the performance of local processes executing at the node. © Springer Science+Business Media Dordrecht 2014. Source

Jeong S.H.,Gyeongsang National University
Tumour biology : the journal of the International Society for Oncodevelopmental Biology and Medicine | Year: 2012

Inorganic pyrophosphatase (PPase) catalyzes the hydrolysis of pyrophosphate to form orthophosphate. Pyrophosphate can substitute for ATP under certain circumstances. We previously conducted a proteomic analysis to investigate tumor-specific protein expression in gastric cancer, and PPase was identified as a potential gastric tumor-specific marker; it was therefore selected for further study. Clinicopathological analysis, using proteomic analysis and immunohistochemistry, was used to validate PPase as a prognostic marker in gastric cancers. Proteomic analysis showed that PPase was overexpressed in patients with lymph node (LN) metastases and high tumor node metastasis (TNM) stages (p < 0.05). Based on immunohistochemistry, patients whose tumors overexpressed PPase had higher T stages, LN metastasis, a higher TNM stage, a higher cancer recurrence rate, and shorter survival times than patients whose tumors exhibited PPase underexpression (p < 0.05). Gain-of-function and loss-of-function approaches were employed to examine the malignant phenotypes of PPase-overexpressing or PPase-depleted cells. A decrease in PPase expression caused a significant decrease in gastric cancer cell migration and invasion in vitro, whereas forced overexpression of PPase enhanced migration but not invasion. Our findings indicate that PPase is involved in gastric tumor progression and that PPase may be a useful marker for poor prognosis of human gastric cancers. Source

Kim Y.-H.,Gyeongsang National University
Ocean Engineering | Year: 2012

The turbulence flow inside the codend and tilt of the codend in a shrimp beam trawl was measured with a Nortek Vector and the towline tension during five fishing operations; data collected for turbulence intensity with codend tilt was analysed under towing speeds. The turbulence intensity at a point in the posterior upper part of the codend ranged from 5 to 40% and decreased significantly by mean flow velocity (0.10.9 m s -1) inside the codend. Simultaneously, the shorter periods of the turbulence flow in the towing or perpendicular direction were located between 2 and 8 s by the FFT method and the Morlet wavelet method. Pitch and roll of the codend also varied each other within S.D<±6° and their shorter period was shown mostly as 3 s around. However, turbulence flow velocities inside the codend were not related to tilt changes or towline tension, which increased significantly with towing speed. As a result, turbulence intensity and periodicity in the codend could affect the manoeuvring of fish swimming and the application of active stimulating devices. © 2012 Elsevier Ltd. All rights reserved. Source

Paek S.-M.,Gyeongsang National University
Molecules | Year: 2014

Total synthesis of macrosphelides is summarized. Synthetic approaches contain the preparation of key fragments and the final ring-closure reaction for unique 16- or 15-membered macrolactone skeletons. Source

EGb 761 is a standardized extract of Ginkgo biloba that appears to have a neuroprotective effect against neurodegenerative diseases. Adult male rats were treated with EGb 761 (100 mg/kg) or vehicle prior to middle cerebral artery occlusion (MCAO), and brains were collected 24 h after MCAO. Proteins that were differentially expressed after EGb 761 treatment during cerebral ischemia were detected using two-dimensional gel electrophoresis. Protein spots with more than a 2.5-fold change in intensity between vehicle-and EGb 761-treated groups were identified by mass spectrometry. The levels of peroxiredoxin-2 and protein phosphatase 2A subunit B were significantly decreased in the vehicle-treated group in comparison to the EGb 761-treated group. In contrast, levels of the collapsing response mediator protein 2 (CRMP2) were significantly increased in vehicle-treated animals, while EGb 761 prevented the injury-induced increase of CRMP2. These results suggest that EGb 761 protects neuronal cells against ischemic brain injury through the specific up-and down-modulation of various proteins. © 2011 World Scientific Publishing Company & Institute for Advanced Research in Asian Science and Medicine. Source

Chung W.S.,Gyeongsang National University
Modern Physics Letters A | Year: 2014

A new kind of charge coherent state called a Zp-graded charge coherent state is constructed by using the complex solution of the equation qp = 1. The p-1 charge operators are also explicitly constructed. We explicitly investigate some nonclassical properties for the Z3-graded charge coherent state. © 2014 World Scientific Publishing Company. Source

Chung W.S.,Gyeongsang National University
Modern Physics Letters B | Year: 2014

In this paper, three-mode nonlinear coherent states are introduced by using the complex solution of the equation q3 = 1. The photon-added or photon-subtracted three-mode nonlinear coherent states are shown to be three-mode nonlinear coherent states with different nonlinear functions. The Z3-graded parity coherent states are introduced as examples of three-mode nonlinear coherent states. Finally, multi-mode coherent states and multi-mode nonlinear coherent states are also constructed in a similar way. © 2014 World Scientific Publishing Company. Source

Hyun T.K.,Gyeongsang National University | Kim J.-S.,Jeju National University
Plant OMICS | Year: 2011

Although many fruits are plant-derived healthy foods, they may harbor a series of allergenic proteins. Based on biochemical and molecular biological approaches, a number of allergens have been identified and characterized in Rosaceae family fruits, such as apple and peach. However, our understanding of the allergens from the Rosoideae subfamily and the Rutaceae family is very limited.Therefore, in this study, we identified gene families, including pathogenesis-related protein 10 (PR-10), non-specific lipid transfer protein (nsLTP), and profilin as allergens in Fragaria vesca (woodland strawberry) and Citrus clementina (mandarin orange). Using comprehensive analysis, we identified 25 putative allergen genes from woodland strawberry and eight mandarin orange genome sequences. The analysis of functional annotation indicated that these allergens have complex physiological roles that are involved in plant defense and plant development. Although further functional analysis of these allergens though the analysis of cross-reactivity of immunoglobulin E antibody to these allergens will be required, our comparative genomic analysis of the allergen genes and encoded proteins in woodland strawberry and mandarin orange provides a basis for future research on developing low-allergenic cultivars without compromising the natural defense of plants. Source

Hwang S.,Gyeongsang National University | Graham W.D.,University of Florida
Journal of the American Water Resources Association | Year: 2014

This study applied three statistical downscaling methods: (1) bias correction and spatial disaggregation at daily time scale (BCSD_daily); (2) a modified version of BCSD which reverses the order of spatial disaggregation and bias correction (SDBC), and (3) the bias correction and stochastic analog method (BCSA) to downscale general circulation model daily precipitation outputs to the subbasin scale for west-central Florida. Each downscaled climate input dataset was then used in an integrated hydrologic model to examine differences in ability to simulate retrospective streamflow characteristics. Results showed the BCSD_daily method consistently underestimated mean streamflow because the highly spatially correlated small precipitation events produced by this method resulted in overestimation of evapotranspiration. Highly spatially correlated large precipitation events produced by the SDBC method resulted in overestimation of the standard deviation of wet season daily streamflow and the magnitude/frequency of high streamflow events. BCSA showed better performance than the other methods in reproducing spatiotemporal statistics of daily precipitation and streamflow. This study demonstrated differences in statistical downscaling techniques propagate into significant differences in streamflow predictions, and underscores the need to carefully select a downscaling method that reproduces precipitation characteristics important for the hydrologic system under consideration. © 2014 American Water Resources Association. Source

Chung W.S.,Gyeongsang National University
Modern Physics Letters A | Year: 2014

In this paper, Holstein-Primakoff realization of Higgs algebra is obtained by using the linear (or quadratic) deformation of Heisenberg algebra and q-deformed Higgs algebra is proposed. Some applications such as Kepler problem in a two-dimensional curved space and SUSY quantum mechanics are also discussed. © 2014 World Scientific Publishing Company. Source

Cho M.-C.,Gyeongsang National University | Oh H.-B.,University of Ulsan | Jun J.-H.,Biowithus Life Science Institute | Kwon O.-J.,Biowithus Life Science Institute
Tissue Antigens | Year: 2014

The new allele A*11:164 showed one nucleotide difference with A*11:01:01 at codon 151 (CAT>CCT). © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. Source

Yu S.-J.,Sun Moon University | Youn S.J.,Gyeongsang National University | Kim H.,Samsung
Physica B: Condensed Matter | Year: 2010

Size effect of thermal radiation is investigated as a function of particle size and temperature. When the size of the particle becomes small, the maximum wavelength of the thermal emission is order of the size, so the spectrum of the thermal emission becomes different compared to well-known blackbody radiation. We calculate the energy density by considering the dimension of the particle. The thermal radiation can be approximated to Wien's law in high frequency range when the size of particle becomes small. The energy density is shown as a function of particle size at a constant temperature. The energy density is also shown as a function of temperature at a constant size. © 2009 Elsevier B.V. All rights reserved. Source

Ohtani M.,Fukui Prefectural University | Ohtani M.,Gyeongsang National University | Miyadai T.,Fukui Prefectural University
Molecular Immunology | Year: 2011

The transcriptional repressors BCL-6 and Blimp-1 are key regulators of B-cell terminal differentiation in mammals. We have previously identified the BCL-6 gene and Blimp-1 gene in fugu (Takifugu rubripes). In the present report, we conducted a functional analysis of fugu BCL-6 and Blimp-1 by using a one-hybrid reporter assay with Gal4 fusion proteins and Gal4DBD luciferase reporter gene. Results from the reporter assays in mammalian cell lines (HeLa, HEK-293, CV-1 and NIH3T3) and the fish cell line EPC show that Gal4-BCL6 and Gal4-Blimp1 strongly repress the transcription of the luciferase gene in all cell lines. Furthermore, deletion analyses show that the N-terminal region of BCL-6 has transcriptional repression activity; the BTB/POZ domain is an especially potent repression domain. In contrast to BCL-6, although the N-acidic domain and PR domain are insufficient for repression, most functional motifs of Blimp-1 are associated with transcriptional repression. These results suggest that BCL-6 and Blimp-1 are functional transcriptional repressors in fugu and that they regulate B-cell terminal differentiation in fugu. © 2010. Source

Sang Chung W.,Gyeongsang National University
Fortschritte der Physik | Year: 2014

In this paper we introduce two types of q-deformed Wigner algebras. One is q-deformation of Wigner algebra with q-reflection symmetry and another is q-deformation of Wigner algebra with reflection symmetry. For two types of q-deformed Wigner algebras, we investigate the representation and the eigenvalue of the position operator. Like q-calculus, we introduce the (q; ν)- numbers, (q; ν)-derivatives and (q; ν)-Hermite polynomials for two algebras. For the deformation parameter q = 1 - ε{lunate} with small ε{lunate}, we discuss the thermodynamics of the particle obeying the q-deformed Wigner algebra. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Chung W.S.,Gyeongsang National University
Fortschritte der Physik | Year: 2014

A new kind of spin coherent state called a Z3-graded spin coherent state is constructed by using the complex solution of the equation q3 = 1. We explicitly find three kinds of Z3-graded spin coherent states. The associated coherent property and spin squeezing are also examined. A new kind of spin coherent state called a Z3-graded spin coherent state is constructed by using the complex solution of the equation q3 = 1. Three kinds of Z3-graded spin coherent states are explicitly found. The associated coherent property and spin squeezing are examined. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Chung W.S.,Gyeongsang National University
International Journal of Modern Physics B | Year: 2014

In this paper, the even and odd truncated coherent states are considered. In this process, the incomplete hyperbolic cosine and sine function are proposed. For the even and odd truncated coherent states, nonclassical properties are investigated. © 2014 World Scientific Publishing Company. Source

Hwang W.R.,Gyeongsang National University | Hulsen M.A.,TU Eindhoven
Macromolecular Materials and Engineering | Year: 2011

The alignment and the aggregation of particles in a viscoelastic fluid in simple shear flow are qualitatively analyzed using a two-dimensional direct numerical simulation. Depending on the shear thinning, solvent viscosity, and Weissenburg number, a typical sequence in structural transitions from random particle configuration to string formation is found with clustering and clustered string formation in between. The solvent viscosity and the Weissenburg number, the ratio of normal stress to shear stress, are found to be the most influential parameters for the onset of string formation. The influence of shear thinning is less clear. More shear thinning seems to promote string formation if the stress ratio is constant. The angular velocity of the particles is reduced by approximately 60% when particles form a string, independent of the parameters used.(Figure Presented) © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Kim G.B.,Gyeongsang National University | Stapleton H.M.,Duke University
Marine Pollution Bulletin | Year: 2010

Little information is available on the levels of brominated compounds found in biota from the Korean Peninsula. In this study, Japanese common squids (Todarodes pacificus) were analyzed for 38 polybrominated diphenyl ethers, two methoxylated polybrominated diphenyl ethers and three stereoisomers of hexabromocyclododecane (α, β, and γ-HBCD) from the east and western coasts of the Korean Peninsula. Among 38 PBDEs, 10 PBDEs were detected and their total concentrations ranged from 21 to 292. ng/g lipid wt with a mean concentration of 108. ng/g lipid wt, while two MeO-BDEs and three isomers of HBCDs were detected in all samples. BDE47 showed the highest residual level, followed by BDE99, 154, 153, 28/33. Concentrations of PBDEs and MeO-BDEs were not significantly different between the both sides of the Korean Peninsula; however, HBCD concentrations were higher levels in the East/Japan Sea than the Yellow Sea, indicating that HBCD sources possibly exist in Japan. © 2010 Elsevier Ltd. Source

Cho Y.J.,Gyeongsang National University | Argyros I.K.,Cameron University | Petrot N.,Naresuan University
Computers and Mathematics with Applications | Year: 2010

In this paper, we introduce an iterative method for finding a common element of the set of solutions of the generalized equilibrium problems, the set of solutions for the systems of nonlinear variational inequalities problems and the set of fixed points of nonexpansive mappings in Hilbert spaces. Furthermore, we apply our main result to the set of fixed points of an infinite family of strict pseudo-contraction mappings. The results obtained in this paper are viewed as a refinement and improvement of the previously known results. © 2010 Elsevier Ltd. All rights reserved. Source

Park M.G.,Yeson Rehabilitation Medicine Hospital | Ha Y.,Gyeongsang National University
Journal of Korean Academy of Nursing | Year: 2014

Purpose: This study was conducted to develop a self-management program using goal setting for patients after a stroke. The program was based on a theory-based Goal setting and Action Planning framework (G-AP), and the effectiveness of the program was examined. Methods: A non-equivalent control group pretest-posttest design was used. The experimental group (n=30) received the self-management program using goal setting based on the G-AP over 7 weeks. The education was delivered individually with a specifically designed stroke workbook. The control group (n=30) received only patient information leaflets about stroke. Results: There were significant differences between the two groups. Stroke knowledge, self-efficacy, and health behavior compliance were significantly higher (all p<.001), and hospital anxiety (p<.001) and depression (p<.001) were significantly lower in the experimental group compared to the control group. Conclusion: This self-management program using goal setting based on a G-AP was found to be useful and beneficial for patients in stroke rehabilitation settings. © 2014 Korean Society of Nursing Science. Source

Bagchi S.,Gyeongsang National University
Advances in Intelligent Systems and Computing | Year: 2015

The computational modeling of neurobiological phenomena is an important area in bio-inspired computing. The understanding of state of consciousness as cognitive function is central to it. The functioning of neurological structures is inherently distributed in nature having a closer match to distributed computing. However, the role of functional neurophysiology is critical in cognition modeling. This paper proposes a mathematical model of state of consciousness by mapping the functional neurophysiology and by inducing distributed computing structures in coherence. The scopes of evolution of consciousness and memory are incorporated into the model. The numerical simulation of the distributed computational model is conducted by considering different choice functions. The results illustrate that, gradual evolution of positive consciousness is deterministic under fair excitation from environment. © Springer International Publishing Switzerland 2015. Source

Hwang S.-J.,Mayo Medical School | Hwang S.-J.,Gyeongsang National University | Melenovsky V.,Mayo Medical School | Melenovsky V.,Institute of Clinical and Experimental Medicine IKEM | Borlaug B.A.,Mayo Medical School
Journal of the American College of Cardiology | Year: 2014

Objectives This study investigated the characteristics, evaluation, prognostic impact, and treatment of coronary artery disease (CAD) in patients with heart failure and preserved ejection fraction (HFpEF). Background CAD is common in patients with HFpEF, but it remains unclear how CAD should be categorized, evaluated for, and treated in HFpEF. Methods Clinical, hemodynamic, echocardiographic, treatment, and outcome characteristics were examined in consecutive patients with previous HFpEF hospitalizations who underwent coronary angiography. Results Of the 376 HFpEF patients examined, 255 (68%) had angiographically-proven CAD. Compared with HFpEF patients without CAD, patients with CAD were more likely to be men, to have CAD risk factors, and to be treated with anti-ischemic medications. However, symptoms of angina and heart failure were similar in patients with and without CAD, as were measures of cardiovascular structure, function, and hemodynamics. Compared with patients without CAD, HFpEF patients with CAD displayed greater deterioration in ejection fraction and increased mortality, independent of other predictors (hazard ratio: 1.71, 95% confidence interval: 1.03 to 2.98; p = 0.04). Complete revascularization was associated with less deterioration in ejection fraction and lower mortality compared with patients who were not completely revascularized, independent of other predictors (hazard ratio: 0.56, 95% confidence interval: 0.33 to 0.93; p = 0.03). Conclusions CAD is common in patients with HFpEF and is associated with increased mortality and greater deterioration in ventricular function. Revascularization may be associated with preservation of cardiac function and improved outcomes in patients with CAD. Given the paucity of effective treatments for HFpEF, prospective trials are urgently needed to determine the optimal evaluation and management of CAD in HFpEF. © 2014 by the American College of Cardiology Foundation. Published by Elsevier Inc. Source

Xia X.,Hebei University of Technology | Chen X.,Hebei University of Technology | Zhang Z.,Hebei University of Technology | Zhao W.,Hebei University of Technology | And 2 more authors.
Materials and Design | Year: 2014

In this paper, closed-cell aluminum foams with different kinds and contents of ceramic microspheres are obtained using melt-foaming method. The distribution and the effects of the ceramic microspheres on the mechanical properties of aluminum foams are investigated. The results show that both kinds of ceramic microspheres distribute in the foams uniformly with part in the cell wall matrix, some in adhere to the cell wall surface and part embed in the cell wall with portion surface exposed to the pores. Ceramic microspheres have an important effect on the yield strength, mean plateau stress, densification strain and energy absorption capacities of aluminum foams. Meanwhile, the content of ceramic microsphere in aluminum foams should be controlled in order to obtain good combination of compressive strength and energy absorption capacity. The reasons are discussed. © 2013 Elsevier Ltd. Source

Sun B.,University of Technology, Sydney | Chen Z.,University of Wollongong | Kim H.-S.,Korea Electrotechnology Research Institute | Ahn H.,Gyeongsang National University | Wang G.,University of Technology, Sydney
Journal of Power Sources | Year: 2011

MnO/C core-shell nanorods were synthesized by an in situ reduction method using MnO2 nanowires as precursor and block copolymer F127 as carbon source. Field emission scanning electron microscopy and transmission electron microscopy analysis indicated that a thin carbon layer was coated on the surfaces of the individual MnO nanorods. The electrochemical properties were evaluated by cyclic voltammetry and galvanostatic charge-discharge techniques. The as-prepared MnO/C core-shell nanorods exhibit a higher specific capacity than MnO microparticles as anode material for lithium ion batteries. © 2010 Elsevier B.V. All rights reserved. Source

Brenna M.,Massey University | Cronin S.J.,Massey University | Smith I.E.M.,University of Auckland | Sohn Y.K.,Gyeongsang National University | Maas R.,University of Melbourne
Lithos | Year: 2012

Jeju Island is the emergent portion of a basaltic volcanic field developed over the last c. 1.8Ma on continental crust. Initial volcanism comprised dispersed, small-volume (<0.01km 3) alkali basaltic eruptions that incrementally constructed a tuff pile. Lavas and scoria from continuing small-scaled monogenetic volcanism capped this foundation. From c. 0.4Ma large-volume (>1km 3) eruptions began, with lavas building a composite shield. Three magma suites can be recognized: Early Pleistocene high-Al alkali (HAA), and Late Pleistocene to Holocene low-Al alkali (LAA) and subalkali (SA). The chemical similarity between small-volume and primitive large-volume eruptions suggests analogous parent magmas and fractionation histories that are independent of erupted volumes. The large-volume magmas evolved to trachyte, which erupted in two distinct episodes: the HAA Sanbangsan suite at c. 750ka and the LAA Hallasan suite at c. 25ka. Sr and Nd isotopes indicate that the early trachytes were contaminated by upper crustal material, whereas the later magmas were not. Both suites bear a Nd isotope signature indicative of lower crustal interaction. Sub-suites transitional between HAA and LAA, and between LAA and SA, indicate that melting occurred in discrete, but adjacent, mantle domains. Throughout the evolution of this volcano, each magma batch erupted separately, and a centralized plumbing system was never created. The Island's central peak (Mt. Halla 1950ma.s.l.) is therefore not a sensu stricto stratovolcano, but marks the point of peak magma output in a distributed magmatic system. Jeju's shape and topography thus represent the spatial variation of fertility of the mantle below it. An increase in melt production in the Late Pleistocene was related to a deepening of the melting zone due to regional tectonic rearrangements. Temporal coincidences between magmatic pulses on Jeju and large-scale caldera eruptive events along the nearest subduction system in Kyushu, Japan, suggest that tectonic extension and changing strain rates may drive volcanism on a regional basis, influencing the intraplate volcanism of Jeju Island. © 2012 Elsevier B.V. Source

Mondal A.K.,The Clean Tech Center | Su D.,The Clean Tech Center | Chen S.,The Clean Tech Center | Kretschmer K.,The Clean Tech Center | And 3 more authors.
ChemPhysChem | Year: 2015

A facile microwave method was employed to synthesize NiCo2O4 nanosheets as electrode materials for lithium-ion batteries and supercapacitors. The structure and morphology of the materials were characterized by X-ray diffraction, fieldemission scanning electron microscopy, transmission electron microscopy and Brunauer-Emmett-Teller methods. Owing to the porous nanosheet structure, the NiCo2O4 electrodes exhibited a high reversible capacity of 891 mAhg-1 at a current density of 100 mAg-1, good rate capability and stable cycling performance. When used as electrode materials for supercapacitors, NiCo2O4 nanosheets demonstrated a specific capacitance of 400 Fg-1 at a current density of 20 Ag-1 and superior cycling stability over 5000 cycles. The excellent electrochemical performance could be ascribed to the thin porous structure of the nanosheets, which provides a high specific surface area to increase the electrode-electrolyte contact area and facilitate rapid ion transport. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA , Weinheim. Source

Jeon K.N.,Gyeongsang National University
Journal of Computer Assisted Tomography | Year: 2016

OBJECTIVE: To evaluate the computed tomography (CT) findings and clinical characteristics of pulmonary tuberculosis (TB) in patients with emphysema, compared with those without emphysema. MATERIALS AND METHODS: Thirty-nine patients (M:F = 36:3; mean age, 64.8 years) who were diagnosed with chronic obstructive pulmonary disease and had emphysema in pretreatment chest CT scans were included in this study (emphysema group). Their clinical presentation, laboratory findings, and CT findings were compared with those of 57 pulmonary TB patients without chronic obstructive pulmonary disease and emphysema (M:F = 52:5; mean age, 64.3 years) (nonemphysema group). RESULTS: Fever was a more frequent clinical presentation and the C-reactive protein level was higher in the emphysema group. Among CT findings, consolidation and ground-glass opacity were seen more frequently in the emphysema group (82% and 69% vs 42% and 19%, respectively, P < 0.001). Consolidation was more often nonsegmental than lobular or segmental. Tree-in-bud appearance was less frequently noted in the emphysema group (36% vs 79%, P < 0.001). The location of main lesions (upper lung vs middle/lower lung) was not different between the 2 groups. CONCLUSIONS: Pulmonary TB in emphysema patients often shows bacterial pneumonia-like features, that is, presence of consolidation and ground-glass opacity and lack of bronchogenic spread on chest CT scans, combined with the presence of fever and a high C-reactive protein level. Sputum smear for acid-fast bacteria should be performed early in emphysema patients with pneumonia in TB-endemic areas.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved. Source

Leong W.L.,National University of Singapore | Vittal J.J.,Gyeongsang National University
Chemical Reviews | Year: 2011

Complexity and diversity in structures, properties, and applications are examined. Zigzag type conformation is also ubiquitous in 1D CPs. The construction of zigzag CPs stemmed from flexible exoditopic ligands and linear or cis-coordinated octahedral metal centers or tetrahedral metal ions. Infinite helical structural motif has special place in supramolecular chemistry because of its similarities in biological systems and enantioselective catalysis. Generally, utilization of flexible or chiral ligands is a facile approach to achieve helical CPs, while many successful examples of spontaneous chirality induction from achiral ligands also have been widespread in the literature. Conformationally flexible ligands are the key success of self-assembly of structural motifs, such as polycatenanes, helices, braids, Borromean rings and rotaxanes. Source

Cho Y.H.,Hanyang University | Kim H.W.,Hanyang University | Nam S.Y.,Gyeongsang National University | Park H.B.,Hanyang University
Journal of Membrane Science | Year: 2011

Asymmetric ultrafiltration (UF) membranes using polysulfone-poly(ethylene oxide) (PSF-PEO) random copolymers, synthesized by a polycondensation reaction, were prepared via a dry/wet phase inversion process. The PEO contents in copolymers varied from 0mol% (PSF) to 20mol% to investigate the effect of PEO on UF membrane structure, properties and performances as well as fouling tolerance. As a pore forming agent, polyvinylpyrrolidones (PVP, Mn 10k-360kDa) with various molecular weights were used to control membrane morphologies and UF performance. Surface atomic compositions were analyzed using an X-ray photoelectron spectroscopy (XPS) to examine the enrichment of PEO segments on the membrane surface after the dry/wet phase inversion process. The pure water flux and PEG rejection (molecular weight cut off) were measured as a function of PEO contents in copolymers, PVP molecular weight, and compositions of the casting solution as well. Protein adsorption and emulsified oil filtration experiments were performed to evaluate fouling resistance for protein and emulsified oil. Compared to commercial PSF UF membranes, the surface wettability of UF membranes prepared from PSF-PEO random copolymers was significantly enhanced by the presence of hydrophilic PEO segments on the membrane surface. PSF-PEO UF membrane also showed higher pure water flux and relatively lower PEG rejection than PSF UF membrane. In the fouling experiments using BSA and emulsified oil, clearly PSF-PEO UF membranes exhibited much improved tolerance to fouling. The amount of BSA adsorption on the membrane surface was reduced significantly with increasing PEO contents and the fouling effect due to emulsified oil was lessened as well. © 2011 Elsevier B.V. Source

Park M.-C.,Songho College | Ha S.-W.,Gyeongsang National University
Communications in Computer and Information Science | Year: 2011

Flight Waypoint visualization of the aircraft is the system which in order to be solved is used the threat against a low altitude task and terrain altitude widely. But, in order to compose a system with GPS about lower, it is widely used with the restriction must construct terrain information where it is huge to it is difficult. In this paper, flight Waypoint and economically visualization Moving Map systems of the Open-Source based for it proposes. First, UDP it leads first from X-Plane and synthetic flight path information, it acquires demonstration and terrain altitude information from the delivery receiving Google Earth. Moving from map systems terrain altitude of altitude and the present location of the aircraft about under mapping from map sever it leads and Waypoint visualization at map information which it brings. Also, altitude comparison of the terrain altitude which it follows in time interval and the aircraft it leads and indicates the terrain location which has the dangerous characteristic of collision at the projected course the monitoring screen which it provides. The outgrowth of this paper in objective of the flight algorithm research back and the flight visualization field could be used flight Waypoint visualization with the economic tool. © 2011 Springer-Verlag. Source

Kang K.,Eulji University | Kang K.,Gyeongsang National University
Bone | Year: 2015

Low bone mineral density (BMD) is associated with carotid atherosclerosis and the incidence of stroke. However, there are no data on the association of BMD with intracranial atherosclerosis. The study population consisted of 357 participants who underwent dual energy x-ray absorptiometric scanning of the lumbar spine and brain 3D time of flight magnetic resonance angiography as part of their voluntary health checks. The basilar, middle cerebral, intracranial internal carotid and intracranial vertebral arteries were evaluated. Low BMD was defined as a T-score of less than - 1. All analyses were stratified by sex and intracranial atherosclerosis location. One hundred seventy-six women (53. years; 66.9% postmenopausal; 33.5% low BMD; 60.2% intracranial atherosclerosis in the anterior circulation (AC); 60.2% intracranial atherosclerosis in the posterior circulation (PC)) and 181 men (51. years; 28.7% low BMD; 61.9% intracranial atherosclerosis in the AC; 55.8% intracranial atherosclerosis in the PC) were included. In women, low BMD was significantly associated with intracranial atherosclerosis in the PC with the odds ratio of 2.57 (95% confidence interval 1.11-5.99). However, intracranial atherosclerosis in the AC was not associated with BMD in women. In men, there were no significant associations between BMD and intracranial atherosclerosis. In conclusion, this study shows that low BMD is associated with subclinical intracranial PC atherosclerosis in women but not in men. © 2015 Elsevier Inc. Source

Lee H.J.,Chung - Ang University | Jeong S.E.,Chung - Ang University | Kim P.J.,Gyeongsang National University | Madsen E.L.,Cornell University | Jeon C.O.,Chung - Ang University
Frontiers in Microbiology | Year: 2015

The communities and abundances of methanotrophs and methanogens, along with the oxygen, methane, and total organic carbon (TOC) concentrations, were investigated along a depth gradient in a flooded rice paddy. Broad patterns in vertical profiles of oxygen, methane, TOC, and microbial abundances were similar in the bulk and rhizosphere soils, though methane and TOC concentrations and 16S rRNA gene copies were clearly higher in the rhizosphere soil than in the bulk soil. Oxygen concentrations decreased sharply to below detection limits at 8 mm depth. Pyrosequencing of 16S rRNA genes showed that bacterial and archaeal communities varied according to the oxic, oxic-anoxic, and anoxic zones, indicating that oxygen is a determining factor for the distribution of bacterial and archaeal communities. Aerobic methanotrophs were maximally observed near the oxic-anoxic interface, while methane, TOC, and methanogens were highest in the rhizosphere soil at 30-200 mm depth, suggesting that methane is produced mainly from organic carbon derived from rice plants and is metabolized aerobically. The relative abundances of type I methanotrophs such as Methylococcus, Methylomonas, and Methylocaldum decreased more drastically than those of type II methanotrophs (such as Methylocystis and Methylosinus) with increasing depth. Methanosaeta and Methanoregula were predominant methanogens at all depths, and the relative abundances of Methanosaeta, Methanoregula, and Methanosphaerula, and GOM_Arc_I increased with increasing depth. Based on contrasts between absolute abundances of methanogens and methanotrophs at depths sampled across rhizosphere and bulk soils (especially millimeter-scale slices at the surface), we have identified populations of methanogens (Methanosaeta, Methanoregula, Methanocella, Methanobacterium, and Methanosphaerula), and methanotrophs (Methylosarcina, Methylococcus, Methylosinus, and unclassified Methylocystaceae) that are likely physiologically active in situ. © 2015 Lee, Jeong, Kim, Madsen and Jeon. Source

Park S.W.,Gyeongsang National University | Kang J.-W.,Sungkyunkwan University | Lee S.-M.,Sungkyunkwan University
Journal of Surgical Research | Year: 2015

Background This study was designed to evaluate the role of Kupffer cells (KCs) in hepatic drug metabolizing dysfunction after hepatic ischemia-reperfusion (IR) in alcoholic fatty liver. Materials and methods Rats were fed the Lieber-DeCarli diet for 5 wk to develop alcoholic fatty liver, then were subjected to 90 min of hepatic ischemia and 5 h of reperfusion. For ablation of KCs, rats were pretreated with gadolinium chloride (GdCl3) 48 and 24 h before the IR procedure. Results After the IR procedure, ethanol diet (ED)-fed rats had higher serum aminotransferase activity compared with the control diet-fed rats. These changes were attenuated by GdCl3. The ED-fed rats exhibited increased hepatic microsomal total cytochrome P450 (CYP) content and nicotinamide adenine dinucleotide phosphate-CYP reductase and CYP1A1, 1A2, 2B1, and 2E1 isozyme activity. After hepatic IR, these increases were reduced to lower levels than observed in the sham group, except CYP2E1 activity. Increases in CYP2E1 activity and its expression were augmented after hepatic IR in ED-fed animals, but were attenuated by GdCl3. Finally, toll-like receptor 4 and myeloid differentiation primary response gene 88 protein expression, nuclear translocation of nuclear factor-κB and activator protein 1, and levels of proinflammatory mediators were further increased in ED-fed animals compared with control diet-fed animals after IR. These increases were attenuated by GdCl3. Conclusions We suggest that KCs contribute to hepatic drug metabolizing dysfunction during hepatic IR in alcoholic fatty liver via the toll-like receptors 4-mediated inflammatory response. © 2015 Elsevier Inc. Source

Kim J.E.,Gyeongsang National University | Lee J.M.,Seoul National University | Baek J.H.,Seoul National University | Han J.K.,Seoul National University | Choi B.I.,Seoul National University
American Journal of Roentgenology | Year: 2012

OBJECTIVE. The purpose of our study was to investigate whether virtual nonenhanced images can replace true nonenhanced images for the evaluation of biliary stones and to compare two virtual nonenhanced images obtained from dual-energy data sets during the late arterial phase (LAP) and portal venous phase (PVP) with true nonenhanced images. MATERIALS AND METHODS. One hundred patients with gallstones (n = 77) or bile duct stones (n = 23) who had undergone dual-source dual-energy CT (using 80kVp and 140kVp with the ratio of dose-partitioning, 1:1.3), were included. The CT numbers for the stone, liver, and bile; stone size; and image noise were assessed for each image set. The conspicuity and size of the stones, image quality, and acceptability of the virtual nonenhanced images as a replacement for true nonenhanced images were assessed. RESULTS. Virtual nonenhanced images from both LAP (VNE LAP) and PVP showed lower CT numbers for the stone and smaller stone size than did true nonenhanced images (p < 0.05). VNE LAP images failed to show stones in 16 patients (16%) with relatively radiolucent bile duct stones (< 78 HU) or small gallstones (< 9 mm 2, < 1.7 mm). There was no difference between the two virtual nonenhanced image sets except for the contrast-to-noise ratio of stone to bile and the image noise (CT numbers for the stone, liver, and muscle; stone size; and contrast-to-noise ratio of stone to liver, p = 1; the CT number for the bile, p = 0.1618; and effective dose, p = 0.7478). VNE LAP images were considered acceptable as a replacement for true nonenhanced images in 89% and 90% by reviewers 1 and 2, respectively. CONCLUSION. Virtual nonenhanced images allow the detection of biliary stones with moderate accuracy, irrespective of the dual-energy contrast-enhanced phase. The detection of gallbladder stones of 9 mm 2 or smaller and of relatively radiolucent bile duct stones of 78 HU or lower is limited. © American Roentgen Ray Society. Source

Kim S.M.,Korea Advanced Institute of Science and Technology | Kim S.M.,KTH Royal Institute of Technology | Jung B.C.,Gyeongsang National University | Choi W.,Korea Advanced Institute of Science and Technology | Sung D.K.,Korea Advanced Institute of Science and Technology
IEEE Transactions on Vehicular Technology | Year: 2013

In this paper, we investigate the effects of heterogeneous mobility on rate adaptation and user scheduling in cellular networks with hybrid automatic repeat request (HARQ). To this end, we first show the performance tradeoff between two extreme scheduling criteria: retransmission-oriented scheduling (ROS) and mixed scheduling (MS) criteria over time-correlated Rayleigh fading channels. Then, we propose an ROS-based joint rate adaptation and user scheduling (JRAUS) policy for cellular networks and compare it with the conventional and reference JRAUS policies. We also evaluate the system-level performance of the proposed ROS-based JRAUS policy in various user distribution and mobility scenarios. In particular, in an asymmetric user distribution and heterogeneous mobility scenario, which is the most general one in practice, the proposed JRUAS policy yields a throughput gain of 49% and a fairness gain of 155% over the conventional JRAUS policies. In this paper, we find that the rate adaptation is significant not only in a single point-to-point link but in multiuser systems with heterogeneous mobility as well. © 1967-2012 IEEE. Source

Protein phosphatase 5 plays a pivotal role in signal transduction in animal and plant cells, and it was previously shown that Arabidopsis protein phosphatase 5 (AtPP5) performs multiple enzymatic activities that are mediated by conformational changes induced by heat shock stress. In addition, transgenic overexpression of AtPP5 gene conferred enhanced heat shock resistance compared with wild-type plant. However, the molecular mechanism underlying this enhanced heat shock tolerance through functional and conformational changes upon heat stress is not clear. In this report, AtPP5 was shown to preferentially interact with its substrate, MDH, under heat stress conditions. In addition, in co-IP analysis, AtPP5 was observed to form a complex with AtHsp90 in Arabidopsis. These results suggest that AtPP5 may enhance thermotolerance via forming multi-chaperone complexes under heat shock conditions in Arabidopsis. Finally, we show that AtPP5 is primarily localized in the cytoplasm of Arabidopsis. Source

Bark K.M.,Gyeongsang National University
Skinmed | Year: 2011

Phototoxicity can be either harmful and induce adverse skin reactions or beneficial and be used therapeutically as in psoralen and UV-A or photodynamic therapy. Hundreds of medicinal plants are widely used in Asia and Western countries in oriental medicine, yet the phototoxicity of oriental medicinal plants is an understudied area. In this contribution, the authors discuss some methods used to measure the phototoxicity of plants and give an overview of the results of their previous and ongoing studies into the phototoxicity of medicinal plants. The authors argue that because they found that more than a quarter of oriental medicinal plants can be phototoxic, such research is helpful for dermatologists and that active phototoxic components extracted from oriental medicinal plants may be used therapeutically. Source

Lee D.-I.,South Korean National Fisheries Research and Development Institute | Eom K.-H.,South Korean National Fisheries Research and Development Institute | Kim G.-Y.,South Korean National Fisheries Research and Development Institute | Baeck G.-W.,Gyeongsang National University
Marine Policy | Year: 2010

The application of scoping is reviewed to improve the efficiency and rationality of the marine environmental impact assessment system applied to the dredging of coastal sediments and the oceanic disposal of dredged material in Korea. Both the impact levels and those items requiring assessment vary in response to differing goals of the coastal activities involved and also to changes in the characteristics of different marine environments. As a consequence, different assessment fields need to be emphasized for evaluation of the impact that both dredging and dumping might have on the sites involved. The status of current assessment procedures is examined and its problems are diagnosed. Following a survey of interested parties and a review of case studies of the oceanic disposal of dredged sediment in other countries, checklists of core assessment items are proposed as part of a revamped review process, along with improvements to the assessment system. © 2010 Elsevier Ltd. Source

Byun J.C.,Jeju National University | Lee N.H.,Jeju National University | Mun D.H.,Jeju National University | Park K.M.,Gyeongsang National University
Inorganic Chemistry Communications | Year: 2010

The chiral dinuclear tetraazadiphenol macrocyclic copper(II) complexes [Cu2([20]-DCHDC)(La)2] {H2[20]-DCHDC = 14,29-dimethyl-3,10,18,25-tetraazapentacyclo-[25,3,1,04,9,1 12,16,019,24]ditriacontane-2,10,12,14,16(32),17,27(31),28, 30-decane-31,32-diol; La = N3 - (II), NCS - (IV) or S2O3 2- (V)} has been synthesized and structurally characterized by elemental analysis, conductance, electronic and IR spectra as well as FAB-MS method. Crystal structure of [Cu2([20]-DCHDC)(N3)2] •2CH3OH (III) determined by X-ray crystallography reveal the two square pyramidal copper centers bridged by the two phenoxide oxygen atoms, with large Cu-O-Cu angles {100.88(10)°}. © 2010 Elsevier B.V. All rights reserved. Source

Kim Y.,Gyeongsang National University
IFAC Proceedings Volumes (IFAC-PapersOnline) | Year: 2014

For a given network topology of linking dynamical systems, determining the least or the most important link(s) or edge(s) in the network in terms of a sensitivity or robustness measure is a complex combinatorial optimization problem. The purpose of solving this problem is to modify the given network topology, in the hope of using a less number of costly communication links while keeping or improving the network's performance. In this paper, this so-called network topology optimization (NTO) problem is approached via finding the least or the most sensitive edge(s) by analytically obtaining the sensitivity of each edge or numerically solving LMIs (linear matrix inequalities). Vehicle formation control simulations are given to support the merit of the proposed approach. © IFAC. Source

Hwang W.R.,Gyeongsang National University | Advani S.G.,University of Delaware | Walsh S.,U.S. Army
Composites Part A: Applied Science and Manufacturing | Year: 2011

A two dimensional direct numerical simulation technique is developed to describe particulate flows in dual-scale porous media to predict particle deposition on the permeable porous surface in liquid composite molding processes. This individual particle level simulation accounts for hydrodynamic interaction between particles and the fluid, especially near a porous wall (fiber tow), and can predict the deposition of the particles on solid or porous surfaces. A Stokes-Brinkman coupling is employed to describe the flow in dual-scale porous media and a fictitious domain approach is used to deal with freely suspended particles in the fluid stream. A single particle deposition process is investigated extensively along with effects of the permeability of porous media, the particle size and the pressure drop. Mechanisms leading to accelerated or delayed deposition of particles are analyzed by investigating the velocity fields around the particle in close proximity of the porous surface. Finally, particle filtration simulation are performed with a large number of particles to demonstrate the feasibility of this scheme to address particle deposition and filtration during manufacturing of composites using liquid composite molding processes in which the particles are mixed with the resin and the suspension is injected into a stationary dual scale preform. © 2011 Elsevier Ltd. All rights reserved. Source

Kwon J.-S.,Korea University | Kwon J.-S.,University of Calgary | Yun S.-T.,Korea University | Lee J.-H.,Korea University | And 2 more authors.
Journal of Hazardous Materials | Year: 2010

Kinetic and equilibrium sorption experiments were conducted on removal of divalent heavy metals (Pb(II), Cu(II), Zn(II), Cd(II)) and trivalent arsenic (As(III)) from aqueous solutions by scoria (a vesicular pyroclastic rock with basaltic composition) from Jeju Island, Korea, in order to examine its potential use as an efficient sorbent. The removal efficiencies of Pb, Cu, Zn, Cd, and As by the scoria (size = 0.1-0.2 mm, dose = 60 g L-1) were 94, 70, 63, 59, and 14%, respectively, after a reaction time of 24 h under a sorbate concentration of 1 mM and the solution pH of 5.0. A careful examination on ionic concentrations in sorption batches suggested that sorption behaviors of heavy metals onto scoria are mainly controlled by cation exchange. On the other hand, arsenic appeared to be sensitive to specific sorption onto hematite (a minor constituent of scoria). Equilibrium sorption tests indicated that the removal efficiency for heavy metals increases with increasing pH of aqueous solutions, which is resulted from precipitation as hydroxides. Similarly, multi-component systems containing heavy metals and arsenic showed that the arsenic removal increases with increasing pH of aqueous solutions, which can be attributed to coprecipitation with metal hydroxides. The empirically determined sorption kinetics were well fitted to a pseudo-second order model, while equilibrium sorption data for heavy metals and arsenic onto scoria were consistent with the Langmuir and Freundlich isotherms, respectively. Natural scoria studied in this work is an efficient sorbent for concurrent removal of divalent heavy metals and arsenic. © 2009 Elsevier B.V. All rights reserved. Source

Park K.-W.,Gyeongsang National University
Microporous and Mesoporous Materials | Year: 2010

Titanosilicate was modified by interlayer surface silylation using octyltriethoxysilane (OTES) and dodecylamine (DDA) in ethanol without a pre-swelling step. The introduction of silyl groups into the interlayer region was confirmed by XRD, FT-IR, RAMAN, SEM, TGA, 29Si NMR and TEM. DDA acts as a gallery expander and silylation catalyst. The evaporation of ethanol from the dispersion yields well-ordered silylation. Layered titanosilicate silicate with large basal spacings between 2.95 and 3.87 nm were investigated. The layered structures of the silylated products were confirmed by swelling behavior upon attachment of alkylsilyl groups. Solid-state 29Si MAS NMR of the silylated samples showed Q3 and Q4 signals as well as T2 signals. The increase in the relative intensity of Q4 for Q3 and the appearance of a T2 signal was attributed to the grafting of OTES to the interlayer surface silanol groups. This method provides a promising route for the preparation of new functional nanomaterials to bond a variety of functional groups to the interlayer surface of layered materials. © 2009 Elsevier Inc. All rights reserved. Source

Meng Q.,University of Western Australia | Yang H.,University of Western Australia | Liu Y.,University of Western Australia | Nam T.-H.,Gyeongsang National University
Intermetallics | Year: 2010

This study investigates a fundamental thermodynamic question about the temperature intervals of the B2-B19′ martensitic transformation in a Ti-50.2 at%Ni alloy. Temperature intervals of thermoelastic martensitic transformations are considered to be caused by internal elastic energies produced by the formation of the martensite (in the case of the forward transformation). The intervals have been traditionally measured by differential scanning calorimetry analysis. This study demonstrates that such measurements are subjective to heating and cooling rate of the measurements and the commonly values reported in the literature are mostly overestimates of the true values, causing errors in the determination of thermodynamic parameters. In this work, by means of varying thermal scanning rate, the true temperature intervals of the B2-B19′ martensitic transformation in a Ti-50.2 at%Ni alloy are determined to be 5.1 K for the forward and 10.1 K for the reverse processes. These values are significantly smaller than those generally reported in the literature. Based on these measurements, variations of the specific elastic strain energy stored between the start and the finish of the transformations are estimated to be 0.386 J/g and 0.778 J/g for the forward and the reverse processes, respectively. © 2010 Elsevier Ltd. All rights reserved. Source

Bagchi S.,Gyeongsang National University
International Journal of Computational Intelligence Systems | Year: 2015

The modeling of biological phenomena and its adaptations to distributed computing are promising research areas. The computational modeling of neurobiological phenomena, such as cognition and consciousness, has potential for applications into bio-inspired distributed computing. The functioning of neurological structures is inherently distributed in nature having a closer match to distributed computing. This paper proposes a mathematical model of state of consciousness by following the functional neurophysiology as well as elements of distributed computing. The scopes of evolution of consciousness and memory are incorporated into the model. The nodal classifications and formation of structural hierarchy in distributed computing nodes by incorporating elements of cognitive model are investigated. Evaluation of the model is made by numerical simulation considering different choice functions. The results illustrate that, model of consciousness can be adapted to bio-inspired distributed computing structures and the gradual evolution of consciousness is deterministic under fair excitations from environment. © The authors. Source

Cho N.,Seoul National University | Jang M.,Seoul National University | Lyou C.Y.,Seoul National University | Park J.S.,Hanyang University | And 2 more authors.
Radiology | Year: 2012

Purpose: To investigate the effect of the combined use of ultrasonographic (US) elastography and color Doppler US on the accuracy of radiologists in distinguishing benign from malignant nonpalpable breast masses and in making the decision for biopsy recommendations at B-mode US. Materials and Methods: This prospective study was conducted with institutional review board approval; written informed consent was obtained. A cohort of 367 biopsy-proved cases in 319 women (age range, 22-78 years; mean age, 48.6 years) with B-mode US, US elastographic, and Doppler US images was included. Five blinded readers independently scored the likelihood of malignancy for four data sets (ie, B-mode US alone, B-mode US and elastography, B-mode US and Doppler US, and B-mode US, US elastography, and Doppler US). The area under the receiver operating characteristic curve(A z) values, sensitivities, and specificities of each data set were compared. Results: The A z of B-mode US, US elastography, and Doppler US (average, 0.844; range, 0.797-0.876) was greater than that of B-mode US alone (average, 0.771; range, 0.738-0.798) for all readers(P = .001 for readers 1, 2, and 3; P < .001 for reader 4; P = .002 for reader 5). When both elastography and Doppler scores were negative, leading to strict downgrading, the specificity increased for all readers from an average of 25.3% (75.4 of 298; range, 6.4%-40.9%) to 34.0% (101.2 of 298; range, 26.5%-48.7%)(P < .001 for readers 1, 2, 4, and 5; P = .016 for reader 3) without a significant change in sensitivity. Conclusion: Combined use of US elastography and color Doppler US increases both the accuracy in distinguishing benign from malignant masses and the specificity in decision-making for biopsy recommendation at B-mode US. © RSNA, 2011. Source

Homma M.,Kanagawa University | Kim S.J.,Gyeongsang National University
Finite Fields and their Applications | Year: 2010

We manage an upper bound for the number of rational points of a Frobenius nonclassical plane curve over a finite field. Together with previous results, the modified Sziklai conjecture is settled affirmatively. © 2010 Elsevier Inc.All rights reserved. Source

Lee S.J.,Gyeongsang National University | Lee J.,Seoul National University | Park Y.S.,Seoul National University | Lee C.-H.,Seoul National University | And 5 more authors.
Journal of Thoracic Oncology | Year: 2014

INTRODUCTION:: The impact of chronic obstructive pulmonary disease (COPD) on the mortality of patients with lung cancer has not been studied extensively. The objective of this study is to compare the mortality and clinical characteristics of patients with non-small-cell lung cancer (NSCLC) according to the presence of COPD. METHODS:: The medical records of 221 smokers diagnosed with NSCLC were reviewed. Eligible patients were dichotomized into the COPD group (n = 111) and the non-COPD group (n = 110). The overall survival and clinical characteristics were compared, and predictors of worse survival were analyzed using Cox proportional hazards regression. RESULTS:: COPD was present in 50.2% of all patients with NSCLC, and most of the patients (92.8%) with COPD were unaware of the disease before the diagnosis of lung cancer. Patients in the COPD group were older and had a lower body mass index, higher pack-years smoking history, higher frequency of dyspnea, and higher incidence of previous malignancy. The overall survival of enrolled patients and propensity score-matched subjects was comparable between the two groups (log-rank test, p = 0.2 and 0.396, respectively). Old age, low body mass index, advanced disease stage (stages III and IV), non-squamous histology, Eastern Cooperative Oncology Group performance status of greater than or equal to 2, weight loss, and coexistence of interstitial lung disease were independent risk factors for shorter survival. CONCLUSION:: COPD frequently and subliminally coexists with NSCLC. Although differences in clinical characteristic did exist, there was no impact of COPD on the mortality of patients with NSCLC with a positive smoking history in this study. Copyright © 2014 by the International Association for the Study of Lung Cancer. Source

Kim J.,KAIST | Kwon S.,KAIST | Kim S.H.,Chonnam National University | Lee C.-K.,Korea Basic Science Institute | And 5 more authors.
Journal of the American Chemical Society | Year: 2012

In nature, complex and well-defined structures are constructed by the self-assembly of biomolecules. It has been shown that β-peptide foldamers can mimic natural peptides and self-assemble into three-dimensional molecular architectures thanks to their rigid and predictable helical conformation in solution. Using shorter foldamers, which can be prepared more easily than longer ones, to form such architectures is highly desirable, but shorter foldamers have been overlooked due to the seemingly inferior number of intramolecular hydrogen bonds to stabilize a folded state in solution. Here we report that a β-peptide tetramer, although it lacks full helical propensity in solution, does self-assemble to form well-defined microtubes with rectangular cross-section by evaporation-induced self-assembly. © 2012 American Chemical Society. Source

Jung B.C.,Gyeongsang National University | Park D.,University of Texas at Austin | Shin W.-Y.,Dankook University
IEEE Transactions on Communications | Year: 2012

We introduce an opportunistic interference mitigation (OIM) protocol, where a user scheduling strategy is utilized in K-cell uplink networks with time-invariant channel coefficients and base stations (BSs) having M antennas. Each BS opportunistically selects a set of users who generate the minimum interference to the other BSs. Two OIM protocols are shown according to the number of simultaneously transmitting users per cell, S: opportunistic interference nulling (OIN) and opportunistic interference alignment (OIA). Then, their performance is analyzed in terms of degrees-of-freedom (DoFs). As our main result, it is shown that KM DoFs are achievable under the OIN protocol with M selected users per cell, if the total number of users in a cell, N, scales at least as SNR^{(K-1)M}. Similarly, it turns out that the OIA scheme with S( © 1972-2012 IEEE. Source

Lee G.,Yonsei University | Cho J.,Yonsei University | Ham S.,Yonsei University | Lee T.,Yonsei University | And 2 more authors.
Automation in Construction | Year: 2012

Tower crane operators often operate a tower crane with blind spots. To solve this problem, video camera systems and anti-collision systems are often deployed. However, the current video camera systems do not provide accurate distance and understanding of the crane's surroundings. A collision-detection system provides location information only as numerical data. This study introduces a newly developed tower crane navigation system that provides three-dimensional information about the building and surroundings and the position of the lifted object in real time using various sensors and a building information modeling (BIM) model. The system quality was evaluated in terms of two aspects, ease of use and usefulness, based on the Technology Acceptance Model (TAM) theory. The perceived ease of use of the system was improved from the initial 3.2 to 4.4 through an iterative design process. The tower crane navigation system was deployed on an actual construction site for 71 days, and the use patterns were video recorded. The results clearly indicated that the tower crane operators relied heavily on the tower crane navigation system during blind lifts (93.33%) compared to the text-based anti-collision system (6.67%). © 2012 Elsevier B.V. All rights reserved. Source

Suantai S.,Chiang Mai University | Cho Y.J.,Gyeongsang National University | Cholamjiak P.,University of Phayao
Computers and Mathematics with Applications | Year: 2012

We investigate strong convergence for Bregman strongly nonexpansive mappings by Halpern's iteration in the framework of reflexive Banach spaces. Using the obtained result, convergence for a family of Bregman strongly nonexpansive mappings is also discussed. As applications, we apply our main result to problems of finding zeros of maximal monotone operators and equilibrium problems in reflexive Banach spaces. © 2011 Elsevier Ltd. All rights reserved. Source

Zhang H.-Z.,Dong - A University | Kim M.H.,Dong - A University | Han J.-Y.,Dong - A University | Jeong Y.-H.,Gyeongsang National University
Platelets | Year: 2014

Published data suggests that the presence of CYP2C19*2 or *3 loss of function (LOF) alleles is indicative of increased platelet aggregation and a higher risk of adverse cardiovascular events after clopidogrel administration. We sought to determine cut-off values using three different assays for prediction of the CYP2C19 phenotype in Korean percutaneous coronary intervention (PCI) patients. We enrolled 244 patients with drug-eluting stent implantation who were receiving clopidogrel and aspirin maintenance therapy for one month or more. Platelet reactivity was assessed with light transmittance aggregometry (LTA), multiple electrode aggregometry (MEA) and the VerifyNow P2Y12 assay (VN). The CYP2C19 genotype was analyzed by polymerase chain reaction (PCR) and snapshot method. The frequency of CYP2C19 LOF allele carriers was 58.6%. The cut-off values from LTA, MEA and VerifyNow for the identification of LOF allele carriers were as follows: 10 M ADP-induced LTA ≥ 48 %, VN > 242 PRU and MEA ≥ 37 U. Between the three tests, correlation was higher between LTA vs. VN assays (r = 0.69) and LTA vs. MEA (r = 0.56), with moderate agreement (κ = 0.46 and κ = 0.46), but between VN assay and MEA, both devices using whole blood showed a lower correlation (r = 0.42) and agreement (κ = 0.3). Our results provide guidance regarding cut-off levels for LTA, VerifyNow and MEA assays to detect the CYP2C19 LOF allele in patients during dual antiplatelet maintenance therapy. © 2014 Informa UK Ltd. Source

Park S.J.,Gachon University | Khang D.,Gyeongsang National University
International Journal of Nanomedicine | Year: 2012

The conformational changes of plasma protein structures in response to carbon nanotubes are critical for determining the nanotoxicity and blood coagulation effects of carbon nanotubes. In this study, we identified that the functional intensity of carboxyl groups on carbon nanotubes, which correspond to the water dispersity or hydrophilicity of carbon nanotubes, can induce conformational changes in the fibrinogen domains. Also, elevation of carbon nanotube density can alter the secondary structures (ie, helices and beta sheets) of fibrinogen. Furthermore, fibrinogen that had been in contact with the nanoparticle material demonstrated a different pattern of heat denaturation compared with free fibrinogen as a result of a variation in hydrophilicity and concentration of carbon nanotubes. Considering the importance of interactions between carbon nanotubes and plasma proteins in the drug delivery system, this study elucidated the correlation between nanoscale physiochemical material properties of carbon nanotubes and associated structural changes in fibrinogen. © 2012 Park and Khang, publisher and licensee Dove Medical Press Ltd. Source

Kole G.K.,National University of Singapore | Vittal J.J.,National University of Singapore | Vittal J.J.,Gyeongsang National University
Chemical Society Reviews | Year: 2013

This tutorial review discusses recent literature on coordination polymers and metal-organic frameworks (MOFs) that exhibit solid-state reactivity and structural transformation under various experimental conditions. Removal or exchange of solvents and guest molecules, exposure to reactive vapours, and external stimuli such as heat, light or mechanochemical force cause such structural transformations and these are often manifested by various physical properties such as colour, magnetism, luminescence, chirality, porosity, etc. due to change in coordination number and geometry, dimensionality, interpenetration, etc. More drastic transformations related to the exchange of metal ions, pillar ligands and insertion of additional ligands between the layers have also been demonstrated. The vast area of dynamic behaviour of coordination polymers and their stimuli-responsive properties have also been addressed briefly. © 2013 The Royal Society of Chemistry. Source

Jeong Y.G.,Gyeongsang National University
The Korean journal of gastroenterology = Taehan Sohwagi Hakhoe chi | Year: 2010

Wegener's granulomatosis (WG) is a disease characterized by a granulomatous necrotizing vasculitis of small vessels. Although any organ systems can be involved, gastrointestinal involvement in WG is notably uncommon. We present a case of 67-year-old man who was admitted with abdominal pain and diarrhea lasting for 3 weeks. Colonoscopy and abdominal CT scan revealed vasculitis and multiple mesenteric lymphadenopathy. Jejunum and mesenteric lymph nodes biopsies confirmed limited form of WG. The present case indicates that WG might involve only gastrointestinal tract and the histological confirmation is important for diagnosis. Source

Kwak Y.-S.,Gyeongsang National University | Weller D.M.,U.S. Department of Agriculture
Plant Pathology Journal | Year: 2013

In agro-ecosystems worldwide, some of the most important and devastating diseases are caused by soil-borne necrotrophic fungal pathogens, against which crop plants generally lack genetic resistance. However, plants have evolved approaches to protect themselves against pathogens by stimulating and supporting specific groups of beneficial microorganisms that have the ability to protect either by direct inhibition of the pathogen or by inducing resistance mechanisms in the plant. One of the best examples of protection of plant roots by antagonistic microbes occurs in soils that are suppressive to take-all disease of wheat. Take-all, caused by Gaeumannomyces graminis var. tritici, is the most economically important root disease of wheat worldwide. Take-all decline (TAD) is the spontaneous decline in incidence and severity of disease after a severe outbreak of take-all during continuous wheat or barley monoculture. TAD occurs worldwide, and in the United States and The Netherlands it results from a build-up of populations of 2,4-diacetylphloroglucinol (2,4-DAPG)-producing fluorescent Pseudomonas spp. during wheat monoculture. The antibiotic 2,4-DAPG has a broad spectrum of activity and is especially active against the take-all pathogen. Based on genotype analysis by repetitive sequence-based-PCR analysis and restriction fragment length polymorphism of phlD, a key 2,4-DAPG biosynthesis gene, at least 22 genotypes of 2,4-DAPG producing fluorescent Pseudomonas spp. have been described worldwide. In this review, we provide an overview of G. graminis var. tritici, the take-all disease, Pseudomonas biocontrol agents, and mechanism of disease suppression. © The Korean Society of Plant Pathology. Source

Zhan J.,Hubei Institute for Nationalities | Jun Y.B.,Gyeongsang National University
Computers and Mathematics with Applications | Year: 2010

By means of ∈-soft sets and q-soft sets, some characterizations of (implicative, positive implicative and fantastic) filteristic soft B L-algebras are investigated. Finally, we prove that a soft set is an implicative filteristic soft B L-algebra if and only if it is both a positive implicative filteristic soft B L-algebra and a fantastic filteristic soft B L-algebra. © 2009 Elsevier Ltd. All rights reserved. Source

Amaranatha Reddy D.,Pusan National University | Ma R.,Pusan National University | Choi M.Y.,Gyeongsang National University | Kim T.K.,Pusan National University
Applied Surface Science | Year: 2015

In this work, we have successfully synthesized ternary nanohybrid composite, ZnS-Ag2S wrapped with reduced graphene oxide (RGO) using hydrothermal method without any surfactant. We have accessed the photocatalytic ability of ZnS-Ag2S-RGO nanocomposite using the oxidation of Rhodamine B (RhB) under simulated sunlight irradiation. The superior photocatalytic ability of ZnS-Ag2S-RGO compared to bare ZnS, was ascribed to an efficient charge transfer from ZnS to Ag2S and graphene sheets. The recyclability results also demonstrated the excellent stability and reliability of the ZnS-Ag2S-RGO. In addition to the excellent photocatalytic degradation properties, the synthesized ZnS-Ag2S-RGO nanocomposite exhibited near white light emission, which implies that careful design and control of the composition could be lead to find application in near UV-white LEDs. The present work provides new insights into the synthesis and characterizations of ternary ZnS-Ag2S-RGO nanocomposites and its wide applications in the environmental protection issues. © 2014 Elsevier B.V. All rights reserved. Source

Ma S.,University of California at Davis | Shah S.,University of California at Davis | Bohnert H.J.,University of Illinois at Urbana - Champaign | Bohnert H.J.,Gyeongsang National University | And 2 more authors.
PLoS Genetics | Year: 2013

Understanding of gene regulatory networks requires discovery of expression modules within gene co-expression networks and identification of promoter motifs and corresponding transcription factors that regulate their expression. A commonly used method for this purpose is a top-down approach based on clustering the network into a range of densely connected segments, treating these segments as expression modules, and extracting promoter motifs from these modules. Here, we describe a novel bottom-up approach to identify gene expression modules driven by known cis-regulatory motifs in the gene promoters. For a specific motif, genes in the co-expression network are ranked according to their probability of belonging to an expression module regulated by that motif. The ranking is conducted via motif enrichment or motif position bias analysis. Our results indicate that motif position bias analysis is an effective tool for genome-wide motif analysis. Sub-networks containing the top ranked genes are extracted and analyzed for inherent gene expression modules. This approach identified novel expression modules for the G-box, W-box, site II, and MYB motifs from an Arabidopsis thaliana gene co-expression network based on the graphical Gaussian model. The novel expression modules include those involved in house-keeping functions, primary and secondary metabolism, and abiotic and biotic stress responses. In addition to confirmation of previously described modules, we identified modules that include new signaling pathways. To associate transcription factors that regulate genes in these co-expression modules, we developed a novel reporter system. Using this approach, we evaluated MYB transcription factor-promoter interactions within MYB motif modules. © 2013 Ma et al. Source

Yao Y.,Tianjin Polytechnic University | Liou Y.-C.,Cheng Shiu University | Kang S.M.,Gyeongsang National University
Computers and Mathematics with Applications | Year: 2010

In this paper, we introduce an iterative method based on the extragradient method for finding a common element of the set of a general system of variational inequalities and the set of fixed points of a strictly pseudocontractive mapping in a real Hilbert space. Furthermore, we prove that the studied iterative method strongly converges to a common element of the set of a general system of variational inequalities and the set of fixed points of a strictly pseudocontractive mapping under some mild conditions imposed on algorithm parameters. © 2010 Elsevier Ltd. All rights reserved. Source

Bagchi S.,Gyeongsang National University
Communications in Computer and Information Science | Year: 2014

Estimations of resource availability and utilizations in a computer system are necessary to achieve fair allocation of resources and to measure performance of a system. The software system designers often look for computing a limiting bound of CPU-utilizations given a schedule in a concurrent multitasking system, where tasks may have different CPU-affinity and IO-affinity. In complex software systems, the variations of CPU-utilizations due to variable scheduling quanta of the concurrent tasks are difficult to estimate through global time-averaging. This paper proposes a computing model of multivariate functional estimation of limiting bound of CPU-utilizations in a concurrent multitasking system comprised of heterogeneous tasks. An analytical model is formulated to compute dynamics of variable scheduling quanta and CPU-utilizations. The relation between continuous single-variable estimation and sampled multi-variable estimation is established. The integral remainder terms along with values of converging polynomials denoting estimation errors are computed. © Springer International Publishing Switzerland 2014. Source

Chung K.S.,Gyeongsang National University | Lee J.I.,Korea Atomic Energy Research Institute | Kim J.L.,Korea Atomic Energy Research Institute
Radiation Measurements | Year: 2012

An efficient computer program has been developed to deconvolute thermoluminescence (TL) glow peaks and optically stimulated (OSL) curves by employing a method of the interactive trap model (ITM). The program is designed to be used easily on the MS Windows-based computer with a graphical user interface. This program could be used to analyze the TL glow curves by using the traditional first-order kinetics (1OK), second-order kinetics (2OK), general order kinetics (GOK), mixed order kinetics (MOK) and the general approximation (GA) method as well as ITM. The program was tested with the generated data and the experimental results of deconvoluted TL glow curves of LiF TLD-100 by assigning five interacting traps and one recombination center. A complete version with full functionalities of this program can be downloaded from the web site http://physica.gnu.ac.kr/TLanal. © 2012 Elsevier Ltd. All rights reserved. Source

Su D.,The Clean Tech Center | Wang C.,Yangzhou University | Ahn H.,Gyeongsang National University | Wang G.,The Clean Tech Center
Physical Chemistry Chemical Physics | Year: 2013

Single crystalline SnO2 nanocrystals (∼60 nm in size) with a uniform octahedral shape were synthesised using a hydrothermal method. Their phase and morphology were characterized by XRD and FESEM observation. TEM and HRTEM analyses identified that SnO2 octahedral nanocrystals grow along the [001] direction, consisting of dominantly exposed {221} high energy facets. When applied as anode materials for Na-ion batteries, SnO2 nanocrystals exhibited high reversible sodium storage capacity and excellent cyclability (432 mA h g-1 after 100 cycles). In particular, SnO 2 nanocrystals also demonstrated a good high rate performance. Ex situ TEM analysis revealed the reaction mechanism of SnO2 nanocrystals for reversible Na ion storage. It was found that Na ions first insert into SnO2 crystals at the high voltage plateau (from 3 V to ∼0.8 V), and that the exposed (1 × 1) tunnel-structure could facilitate the initial insertion of Na ions. Subsequently, Na ions react with SnO2 to form NaxSn alloys and Na2O in the low voltage range (from ∼0.8 V to 0.01 V). The superior cyclability of SnO 2 nanocrystals could be mainly ascribed to the reversible Na-Sn alloying and de-alloying reactions. Furthermore, the reduced Na2O "matrix" may help retard the aggregation of tin nanocrystals, leading to an enhanced electrochemical performance. This journal is © the Owner Societies 2013. Source

Lee T.,Gyeongsang National University | Ouarda T.B.M.J.,INRS ETE | Ouarda T.B.M.J.,Masdar Institute of Science and Technology
Journal of Geophysical Research: Atmospheres | Year: 2011

Long-term nonstationary oscillations (NSOs) are commonly observed in climatological data series such as global surface temperature anomalies (GSTA) and low-frequency climate oscillation indices. In this work, we present a stochastic model that captures NSOs within a given variable. The model employs a data-adaptive decomposition method named empirical mode decomposition (EMD). Irregular oscillatory processes in a given variable can be extracted into a finite number of intrinsic mode functions with the EMD approach. A unique data-adaptive algorithm is proposed in the present paper in order to study the future evolution of the NSO components extracted from EMD. To evaluate the model performance, the model is tested with the synthetic data set from Rössler attractor and with GSTA data. The results of the attractor show that the proposed approach provides a good characterization of the NSOs. For GSTA data, the last 30 observations are truncated and compared to the generated data. Then the model is used to predict the evolution of GSTA data over the next 50 years. The results of the case study confirm the power of the EMD approach and the proposed NSO resampling (NSOR) method as well as their potential for the study of climate variables. Copyright 2011 by the American Geophysical Union. Source

Ko J.-H.,Seoul National University | Mitina I.,Seoul National University | Tamada Y.,University of Wisconsin - Madison | Tamada Y.,Japan National Institute for Basic Biology | And 7 more authors.
EMBO Journal | Year: 2010

In Arabidopsis, the rapid-flowering summer-annual versus the vernalization-requiring winter-annual growth habit is determined by natural variation in FRIGIDA (FRI) and FLOWERING LOCUS C (FLC). However, the biochemical basis of how FRI confers a winter-annual habit remains elusive. Here, we show that FRI elevates FLC expression by enhancement of histone methyltransferase (HMT) activity. EARLY FLOWERING IN SHORT DAYS (EFS), which is essential for FRI function, is demonstrated to be a novel dual substrate (histone H3 lysine 4 (H3K4) and H3K36)-specific HMT. FRI is recruited into FLC chromatin through EFS and in turn enhances EFS activity and engages additional HMTs. At FLC, the HMT activity of EFS is balanced by the H3K4/H3K36- and H3K4-specific histone demethylase (HDM) activities of autonomous-pathway components, RELATIVE OF EARLY FLOWERING 6 and FLOWERING LOCUS D, respectively. Loss of HDM activity in summer annuals results in dominant HMT activity, leading to conversion to a winter-annual habit in the absence of FRI. Thus, our study provides a model of how growth habit is determined through the balance of the H3K4/H3K36-specific HMT and HDM activities. © 2010 European Molecular Biology Organization. Source

Yang H.J.,Stanford University | Shin W.-Y.,Dankook University | Jung B.C.,Gyeongsang National University | Paulraj A.,Stanford University
IEEE Transactions on Wireless Communications | Year: 2013

We consider the K-cell multiple-input multiple-output (MIMO) interfering multiple-access channel (IMAC) with time-invariant channel coefficients, where each cell consists of a base station (BS) with M antennas and N users having L antennas each. In this paper, we propose two opportunistic interference alignment (OIA) techniques utilizing multiple transmit antennas at each user: antenna selection-based OIA and singular value decomposition (SVD)-based OIA. Their performance is analyzed in terms of user scaling law required to achieve KS degrees-of-freedom (DoF), where S(≤ M) denotes the number of simultaneously transmitting users per cell. We assume that each selected user transmits a single data stream at each time-slot. It is shown that the antenna selection-based OIA does not fundamentally change the user scaling condition if L is fixed, compared with the single-input multiple-output (SIMO) IMAC case, which is given by SNR(K-1)S, where SNR denotes the signal-to-noise ratio. In addition, we show that the SVD-based OIA can greatly reduce the user scaling condition to SNR(K-1)S-L+1 through optimizing a weight vector at each user. Simulation results validate the derived scaling laws of the proposed OIA techniques. The sum-rate performance of the proposed OIA techniques is compared with the conventional techniques in MIMO IMAC channels and it is shown that the proposed OIA techniques outperform the conventional techniques. © 2002-2012 IEEE. Source

Choi S.-H.,Gyeongsang National University
Desalination | Year: 2016

Although the current desalination market has shifted to the reverse osmosis (RO) process, the thermal process is still main in the Gulf countries. The thermal desalination processes are commonly classified into the multi-stage flashing (MSF) and the multi-effect distillation (MED). From the viewpoint of a thermal efficiency, the MED type is more advantageous than the MSF type, but the MSF type is more suitable for a large capacity. Up to 1990s, many MSF plants were built in the Middle Eastern countries and most of them have been currenly operated. This study doesn't include any new innovative methodology of the MSF process, but suggests the improvement method of freshwater productivity by re-utilizing the brines of a few top evaporators. The brine re-utilization proposed in this study can be easily achieved in the existing MSF plants by installing only an additional piping. Since the brine temperatures are orderly reduced according to the stage in the MSF process, the freshwater productivity increase was attempted by supplying the brines of a few top stages the end stages. The results showed the increased freshwater production of 1.18–2.10% and the reduced specific thermal energy consumption of 1.90–3.35% without any change of the operating conditions. © 2016 Source

Woo S.H.,Gyeongsang National University
Journal of Laparoendoscopic and Advanced Surgical Techniques | Year: 2013

Objective: A thyroid isthmus nodule is a relatively rare condition. A small number of patients will present with thyroid mass isolated at the thyroid isthmus, which can cause discomfort in swallowing and cosmetic problems. Thus, some patients choose to have these nodules excised. The surgical removal of the thyroid isthmus mass is usually accomplished through an external incision of the neck. However, this procedure inevitably results in a neck scar. Patient and Methods: We report a case of an 18-year-old woman with a thyroid isthmus mass. We implemented a modified approach for the removal of the thyroid isthmus mass by using a frenotomy incision of the mouth, accompanied by an endoscope system. Results: A modified approach for the removal of the thyroid isthmus mass was used on the patient. The total operating time was 70 minutes. The patient continues to be free of any diseases 12 months after the excision. Conclusions: Resection of the thyroid isthmus mass can be performed by an intraoral endoscope-assisted approach through a frenotomy incision of the mouth. We described the detailed procedures for an endoscope-assisted transoral thyroid isthmus mass excision using a frenotomy incision. © Copyright 2013, Mary Ann Liebert, Inc. 2013. Source

Moon Y.H.,Gyeongsang National University | Yoon K.S.,Korea Aerospace Industries LTD. | Park S.-T.,Electronics and Telecommunications Research Institute | Shin I.H.,Electronics and Telecommunications Research Institute
IEEE Transactions on Multimedia | Year: 2013

In this paper, a new fast encoding algorithm based on an efficient motion estimation (ME) process is proposed to accelerate the encoding speed of the scalable video coding standard. Through analysis of the ME process performed in the enhancement layer, we discovered that there are redundant MEs and some MEs can simply be unified at the fully overlapped search range (FOSR). In order to make the unified ME more efficient, we theoretically derive a skip criterion to determine whether the computation of rate-distortion cost can be omitted. In the proposed algorithm, the unnecessary MEs are removed and a unified ME with the skip criterion is applied in the FOSR. Simulation results show that the proposed algorithm achieves computational savings of approximately 46% without coding performance degradation when compared with the original SVC encoder. © 2012 IEEE. Source

Kang K.,Eulji University | Kang K.,Gyeongsang National University
Atherosclerosis | Year: 2014

Objective: Serum calcium and phosphate concentrations are independent risk factors for stroke and positively associated with extracranial carotid atherosclerosis. We evaluated whether higher serum calcium and phosphate concentrations would be associated with intracranial atherosclerosis in a stroke-free Korean population. Methods: We retrospectively analyzed the records of 361 stroke-free subjects who consecutively visited a general health promotion center. Included subjects had serum calcium, phosphate, and albumin drawn and underwent brain magnetic resonance angiography. The basilar, middle cerebral, intracranial internal carotid, and intracranial vertebral arteries were evaluated. Serum calcium concentration was corrected for serum albumin concentration. Results: Mean±SD values were 52±10 years for age, 2.35±0.09mmol/l for uncorrected serum calcium concentration, 2.24±0.08mmol/l for corrected serum calcium concentration, and 1.19±0.18mmol/l for serum phosphate concentration. Seventy-four subjects (21%) had intracranial atherosclerosis. Subjects in the upper three quartiles of corrected serum calcium concentration had a significantly greater risk for intracranial atherosclerosis compared with the lowest quartile with the odds ratios of 3.50 (95% confidence interval 1.50-8.15), 3.11 (95% confidence interval 1.26-7.69), and 3.77 (95% confidence interval 1.58-9.03), respectively. However, serum phosphate and uncorrected serum calcium concentrations were not associated with intracranial atherosclerosis. Conclusion: Corrected serum calcium concentrations are positively associated with the presence of intracranial atherosclerosis. © 2013 Elsevier Ireland Ltd. Source

Kim Y.-H.,Gyeongsang National University
Fisheries and Aquatic Science | Year: 2014

The motion of the otter board on a trawl can affect the motion of trawl nets, and the motion of the codend can affect fish selectivity. Preliminary measurements of the tilt of bottom trawl gear were carried out to compare the tilts of the otter board and codend. The tilt of the otter board was measured by Vector and tilt at 1.5 m anterior to the end of the codend, and the middle upper panel was measured with a micro-DST-tilt logger. Tilt data such as yaw, pitch, and roll were analyzed by the fast Fourier transformation method and global wavelet and event analyses for the period or amplitude. The mean period ± standard deviation of the tilt in the otter board, (5-6) ± 2 s, was similar to the period of the codend, (4-6) ± (2-3) s, whereas the amplitude of the codend was greater than that of the otter board. The yaw and pitch periods were not significantly different between the otter board and codend, but roll was different. Furthermore, the tilt period frequencies of the otter board and codend were not significantly different. Accordingly, the tilt motion of the codend was mostly related to the tilt of the otter board. © 2014 The Korean Society of Fisheries and Aquatic Science. Source

Kang M.,Gyeongsang National University
Fisheries and Aquatic Science | Year: 2014

I provide an overview of the application of hydroacoustic methods in South Korea to understand the current research status in relation to fisheries acoustics and to determine which areas require further study. One main purpose for using a scientific echosounder, a representative tool using the hydroacoustic method, is to evaluate the abundance of fisheries resources. Thus, two representative methods for abundance estimation are described. The history of fisheries acoustics worldwide is also summarized. © 2014 The Korean Society of Fisheries and Aquatic Science. Source

Levine G.N.,Baylor College of Medicine | Jeong Y.-H.,Gyeongsang National University | Goto S.,Tokai University | Anderson J.L.,University of Utah | And 3 more authors.
Nature Reviews Cardiology | Year: 2014

Guideline recommendations on the use of dual antiplatelet therapy (DAPT) in patients with acute coronary syndromes and in those undergoing percutaneous coronary intervention (PCI) have been formulated by both the ACC/AHA and the ESC. These recommendations are based primarily on large, phase III, randomized, controlled trials of the P2Y 12 inhibitors clopidogrel, prasugrel, and ticagrelor. However, few East Asian patients have been included in the trials to assess the use of these agents, particularly the newer agents prasugrel and ticagrelor. Additionally, an increasing body of data suggests that East Asian patients have differing risk profiles for both thrombophilia and bleeding compared with white patients, and that a different 'therapeutic window' of on-treatment platelet reactivity might be appropriate in East Asian patients. Furthermore, a phenomenon referred to as the 'East Asian paradox' has been described, in which East Asian patients have a similar or even a lower rate of ischaemic events after PCI compared with white patients, despite a higher level of platelet reactivity during DAPT. Recognizing these concerns, the World Heart Federation has undertaken this evidence-based review and produced this expert consensus statement to determine the antiplatelet treatment strategies that are most appropriate for East Asian patients. © 2015 Macmillan Publishers Limited. Source

Bahk J.Y.,Gyeongsang National University
Experimental and clinical transplantation : official journal of the Middle East Society for Organ Transplantation | Year: 2010

OBJECTIVES: Stem cells are characterized by self renewal and multipotent differentiation.We report the effects of intracavernosal transplant of human umbilical cord blood stem cells on diabetic erectile dysfunction. MATERIALS AND METHODS: Seven type 2 diabetics who had failed to achieve an erection for at least 6 months despite medications, and who are currently awaiting penile prostheses, participated. All laboratory results were normal, except for impotence and diabetes mellitus. A total of 1.5 x 10(7) human umbilical cord blood stem cells were infused into the corpus cavernosum. No immunosuppressive measures were taken in any of the patients. International index of erectile function-5, SEP, GAQ, erection diary, blood glucose diary, and medication dosage were followed for 9 months. RESULTS: The mean age was 69.5 years (range, 57-87 years). Morning erections were regained in 3 participants within 1 month, and for all except 1 by the third month, and maintained for more than 6 months. Rigidity increased as the result of stem cell therapy alone, but was insufficient for penetration. With the addition of PDE5 inhibitor before coitus, 2 achieved penetration and experienced orgasm, and maintained for more than 6 months; however, 1 participant could not achieved penetration at ninth month. All but 1 reported increased desire. During follow-up, 2 returned for prosthesis, 4 returned to a nonerectile condition at 9 months, and 1 maintained erection sufficient for coitus with medication until the 11th month. Blood glucose levels decreased by 2 weeks, and medication dosages were reduced in all but 1 subject for 4 to 7 months. Glycosylated hemoglobin levels improved after treatment for up to 3 to 4 months. CONCLUSIONS: Human umbilical cord blood stem cell therapy has positive effects on erectile dysfunction and diabetes mellitus. Stem cells and unknown humoral factors of human umbilical cord blood stem cells mediate mechanism may contribute to these positive effects. Source

Jeong M.-Y.,Gyeongsang National University | Brasselet S.,Aix - Marseille University | Cho B.R.,Korea University | Lim T.-K.,Korea University
Optics Express | Year: 2011

We present theoretical and experimental demonstrations of the electro-optic activity in crystalline molecular thin films with octupolar D3h symmetry. Applying a longitudinal electric field modulation within the molecular plane, we analyze the induced refractive index change relative to the orientation of the octupoles in their plane, and show that a maximum value is reached when one octupolar branch lies along the direction of the modulating field. These characteristics, as well as their electric field dependence, are drastically different from more traditional one-dimensional symmetry samples, bringing additional advantages related to electro-optic coupling possibilities. © 2011 Optical Society of America. Source

Kim H.T.,Korea University | Chung M.G.,Gyeongsang National University | Kim K.-J.,Korea University
Molecules and Cells | Year: 2014

In this study, the chloroplast (cp) genome sequences from three early diverged leptosporangiate ferns were completed and analyzed in order to understand the evolution of the genome of the fern lineages. The complete cp genome sequence of Osmunda cinnamomea (Osmundales) was 142,812 base pairs (bp). The cp genome structure was similar to that of eusporangiate ferns. The gene/intron losses that frequently occurred in the cp genome of leptosporangiate ferns were not found in the cp genome of O. cinnamomea. In addition, putative RNA editing sites in the cp genome were rare in O. cinnamomea, even though the sites were frequently predicted to be present in leptosporangiate ferns. The complete cp genome sequence of Diplopterygium glaucum (Gleicheniales) was 151,007 bp and has a 9.7 kb inversion between the trnL-CAA and trnV-GCA genes when compared to O. cinnamomea. Several repeated sequences were detected around the inversion break points. The complete cp genome sequence of Lygodium japonicum (Schizaeales) was 157,142 bp and a deletion of the rpoC1 intron was detected. This intron loss was shared by all of the studied species of the genus Lygodium. The GC contents and the effective numbers of codons (ENCs) in ferns varied significantly when compared to seed plants. The ENC values of the early diverged leptosporangiate ferns showed intermediate levels between eusporangiate and core leptosporangiate ferns. However, our phylogenetic tree based on all of the cp gene sequences clearly indicated that the cp genome similarity between O. cinnamomea (Osmundales) and eusporangiate ferns are symplesiomorphies, rather than synapomorphies. Therefore, our data is in agreement with the view that Osmundales is a distinct early diverged lineage in the leptosporangiate ferns. © The Korean Society for Molecular and Cellular Biology. All rights reserved. Source

Jun Y.B.,Gyeongsang National University
Journal of Multiple-Valued Logic and Soft Computing | Year: 2013

In BCK-algebras, the notion of commutative intersection-soft ideal is introduced, and related properties are investigated. Characterizations of a commutative intersection-soft ideal are considered. Conditions for an intersection-soft ideal to be commutative are provided. Extension property of a commutative intersection-soft ideal is established. The problem of classifying (commutative) intersection-soft ideals by their inclusive sets is solved. ©2013 Old City Publishing, Inc. Source

Lee K.H.,Chonbuk National University | Han S.-W.,Chonbuk National University | Kwon K.-Y.,Gyeongsang National University | Park J.B.,Chonbuk National University
Journal of Colloid and Interface Science | Year: 2013

Graphene has been modified with palladium nanoparticles (Pd NPs) to develop high performance catalysts for the Sonogashira cross coupling reaction. In this research, graphite oxide (GO) sheets exfoliated from graphite were impregnated with Pd(OAc)2 to prepare Pd2+/GO. Thermal treatments of the Pd2+/GO in H2 flow at 100°C produced Pd/graphene (Pd/G) nanocomposites. TEM images show that Pd NPs were distributed quite uniformly on the graphene sheet without obvious aggregation, and the mean size of Pd NPs was determined to be less than 2nm in diameter. Morphological and chemical structures of the GO, Pd2+/GO, and Pd/G were investigated using FT-IR, XRD, XPS, and XAFS. The resulting Pd/G showed excellent catalytic efficiency in the Sonogashira reaction and offers significant advantages over inorganic supported catalysts such as simple recovery and recycling. Finally, deactivation process of the Pd/G in recycling was investigated. We believe that the remarkable reactivity of the Pd/G catalyst toward the Sonogashira reaction is attributed to the high degree of the Pd NP dispersion and thus the increased low coordination numbers of smaller Pd NPs. © 2013. Source

Lee J.-H.,Sunchon National University | Won Y.-S.,Sunchon National University | Park K.-H.,Gyeongsang National University | Lee M.-K.,Sunchon National University | And 3 more authors.
Apoptosis | Year: 2012

Celastrol has been reported to possess anticancer effects in various cancers; however, the precise mechanism underlying ROS-mediated mitochondriadependent apoptotic cell death triggered by celastrol treatment in melanoma cells remains unknown. We showed that celastrol effectively induced apoptotic cell death and inhibited tumor growth using tissue culture and in vivo models of B16 melanoma. In addition to apoptotic cell death in B16 cells, several apoptotic events such as PARP cleavage and activation of caspase were confirmed. Pretreatment with caspase inhibitor modestly attenuated the celastrol-induced increase in PARP cleavage and sub-G1 cell population, implying that caspases play a partial role in celastrol-induced apoptosis. Moreover, ROS generation was detected following celastrol treatment. Blocking of ROS accumulation with ROS scavengers resulted in inhibition of celastrol-induced Bcl-2 family-mediated apoptosis, indicating that celastrol-induced apoptosis involves ROS generation as well as an increase in the Bax/Bcl-2 ratio leading to release of cytochrome c and AIF. Importantly, silencing of AIF by transfection of siAIF into cells remarkably attenuated celastrol-induced apoptotic cell death. Moreover, celastrol inhibited the activation of PI3K/AKT/mTOR signaling cascade in B16 cells. Our data reveal that celastrol inhibits growth and induces apoptosis in melanoma cells via the activation of ROS-mediated caspase-dependent and -independent pathways and the suppression of PI3K/AKT signaling. © Springer Science+Business Media New York 2012. Source

Kang J.H.,University of Texas M. D. Anderson Cancer Center | Kang J.H.,Gyeongsang National University | Shin S.H.,University of Texas M. D. Anderson Cancer Center | Shin S.H.,Kosin University | Bruera E.,University of Texas M. D. Anderson Cancer Center
Cancer Treatment Reviews | Year: 2013

Delirium is a frequently under-recognized complication in patients with advanced cancer. Uncontrolled delirium eventually leads to significant distress to patients and their families. However, delirium episodes can be reversed in half of these patients by eliminating precipitating factors and using appropriate interventions. The purpose of this narrative review is to discuss the most recent updates in the literature on the management of delirium in patients with advanced cancer. This article addresses the epidemiology, cause, pathophysiology, clinical characteristics, and assessment of delirium as well as various treatment options, including nonpharmacologic intervention and palliative sedation. © 2012 Elsevier Ltd. Source

Chai J.-Y.,Seoul National University | Bahk Y.Y.,Korea University | Sohn W.-M.,Gyeongsang National University
Korean Journal of Parasitology | Year: 2013

In 2005, we reported the infection status of 438 stray cats with various species of intestinal helminths, including nematodes (4 species), trematodes (23 species), and cestodes (5 species) in the Republic of Korea. However, morphologic details of each helminth species have not been provided. In the present study, we intended to describe morphologic details of 13 trematode species which were either new fauna of cats (10 species) or new fauna of not only cats but also all animal hosts (3 species). The worms were fixed in 10% neutral buffered formalin under a cover slip pressure, stained with Semichon's acetocarmine, and then observed using a light microscope equipped with a micrometer. The 13 subjected species included members of the Heterophyidae (Stellantchasmus falcatus, Stictodora fuscata, Stictodora lari, Centrocestus armatus, Procerovum varium, and Cryptocotyle concava), Echinostomatidae (Echinostoma hortense, Echinostoma revolutum, Echinochasmus japonicus, and Stephanoprora sp.), Diplostomidae (Neodiplostomum seoulense), Plagiorchi- idae (Plagiorchis muris), and Dicrocoeliidae (Eurytrema pancreaticum). By the present study, Cryptocotyle sp. and Neo- diplostomum sp. recored in our previous study were identifed as C. concava and N. seoulense, respectively. Three species, P. varium, C. concava, and Stephanoprora sp., are new trematode fauna in Korea. © 2013, Korean Society for Parasitology and Tropical Medicine. Source

Kim J.,Indiana University Bloomington | Kim J.,Gyeongsang National University | Heindl J.E.,Indiana University Bloomington | Fuqua C.,Indiana University Bloomington
PLoS ONE | Year: 2013

The α-Proteobacterium Agrobacterium tumefaciens has proteins homologous to known regulators that govern cell division and development in Caulobacter crescentus, many of which are also conserved among diverse α-Proteobacteria. In light of recent work demonstrating similarity between the division cycle of C. crescentus and that of A. tumefaciens, the functional conservation for this presumptive control pathway was examined. In C. crescentus the CtrA response regulator serves as the master regulator of cell cycle progression and cell division. CtrA activity is controlled by an integrated pair of multi-component phosphorelays: PleC/DivJ-DivK and CckA-ChpT-CtrA. Although several of the conserved orthologues appear to be essential in A. tumefaciens, deletions in pleC or divK were isolated and resulted in cell division defects, diminished swimming motility, and a decrease in biofilm formation. A. tumefaciens also has two additional pleC/divJ homologue sensor kinases called pdhS1 and pdhS2, absent in C. crescentus. Deletion of pdhS1 phenocopied the ΔpleC and ΔdivK mutants. Cells lacking pdhS2 morphologically resembled wild-type bacteria, but were decreased in swimming motility and elevated for biofilm formation, suggesting that pdhS2 may serve to regulate the motile to non-motile switch in A. tumefaciens. Genetic analysis suggests that the PleC/DivJ-DivK and CckA-ChpT-CtrA phosphorelays in A. tumefaciens are vertically-integrated, as in C. crescentus. A gain-of-function mutation in CckA (Y674D) was identified as a spontaneous suppressor of the ΔpleC motility phenotype. Thus, although the core architecture of the A. tumefaciens pathway resembles that of C. crescentus there are specific differences including additional regulators, divergent pathway architecture, and distinct target functions. © 2013 Kim et al. Source

Song II Y.,Hanwha R and nter | Shin V.,Gyeongsang National University
IET Control Theory and Applications | Year: 2013

This study presents a new robust filtering method in modelling an active multisensory suspension system with measurement delays and parameteric uncertainties in a state-space dynamical model. To achieve good performance of the system, a new distributed fusion receding horizon filtering frameworks are constructed to couple the continuous dynamics with the multisensory discrete measurements, and to coordinately deal with the parametric uncertainty and time-delays. The novel filtering algorithm is proposed based on the receding horizon strategy, standard mixed continuous-discrete Kalman filtering and discrete Kalman filtering for systems with time-delays in order to achieve high estimation accuracy and stability under parametric uncertainties. The key theoretical contributions of this study are the derivation of the error cross-covariance equations between the local receding horizon filters in order to compute the optimal matrix fusion weights. The high accuracy and efficiency of the new filter are demonstrated through its implementation and performance and then compared to the existing vehicle active suspension system. © The Institution of Engineering and Technology 2013. Source

Kweon G.,Gyeongsang National University | Maxton C.,Veris Technologies Inc
Biosystems Engineering | Year: 2013

This research was conducted to develop an inexpensive on-the-go optical sensor for soil organic matter (OM) sensing. Diffuse reflectance for 86 soil samples from Kansas and Illinois was measured by a spectrometer in a laboratory. Stepwise multiple linear regression (SMLR) and B-matrix in partial least squares (PLS) were used to determine important wavelengths for soil OM measurement. The wavelengths of 660 and 940nm, identified by both SMLR and PLS, were used for an optical sensor. The developed optical sensor with dual wavelength was evaluated with dry and wet soils in the lab and the relationship between reflectance and OM showed a coefficient of determination (R2) as high as 0.91. Gaps between soil and the sensor window reduced the ability to estimate soil organic matter, thus the sensor window should press firmly against soil. In field tests, all fields gave good results, with RPD (ratio of prediction to deviation=standard deviation/root mean square error) of 2 or greater for OM estimation. In comparison with a NIR spectrophotometer shank unit, the optical sensor showed similar results for OM mapping pattern with coefficient of determination as 0.86. The level of agreement between the two maps was 0.56 for overall accuracy and 0.34 for kappa coefficient. Further field tests need to be implemented to evaluate the soil organic matter estimation with the sensor over different types of soils in a wider set of locations. © 2013 IAgrE. Source

Young S.-Y.,Korea University of Technology and Education | Nam T.-H.,Gyeongsang National University
Journal of Alloys and Compounds | Year: 2013

This paper presents a three-dimensional calculation model for martensitic transformation and the numerical results were compared with experimental load-biased thermal cycling data of Ti-35Ni-15Cu (at%) shape memory alloy. Our new model accounts for the self-accommodation part of the variants separately in addition to the conventional individual variants. Thermodynamic driving force for a transformation between bistable states was provided in terms of a potential energy of each variant. Transformation kinetic parameters were applied differentially to the self-accommodation and the individual variants. By this approach, interplay between thermodynamics and kinetics of the self-accommodation and the individual variants could be successfully captured. The model has predicted the experimental result more accurately than the model without the self-accommodation part. © 2012 Elsevier B.V. Source

Lee G.W.,Gyeongsang National University
Genetics and molecular research : GMR | Year: 2012

Different treatment outcomes and prognoses in patients with breast cancer can be observed with similar clinical predictors; this is because the biology of breast cancer is complex and heterogenous, involving multiple unknown contributing factors. We looked for plasma human mammaglobin (hMAM) mRNA by RT-PCR in 82 Korean patients with breast cancer to determine if there is an association between the presence of plasma hMAM mRNA in these patients and known prognostic factors. The prognostic usefulness of detection of plasma hMAM mRNA expression in these patients was also evaluated by determining overall survival and event-free survival. A significant difference was observed in the rate of positivity of plasma hMAM mRNA between the early stages of cancer (stages I-II, 23.4%) and advanced stages (stages III-IV, 82.9%). The expression rates of estrogen receptor, progesterone receptor, and HER-2/neu in the breast tissue of these patients, by immunohistochemistry, were 69.5, 75.6, and 20.7%, respectively. In the univariate analysis, plasma hMAM expression was significantly correlated with high histological and nuclear grades, nodal metastasis, and negative estrogen receptor and progesterone receptor status. Patients negative for plasma hMAM mRNA had significantly higher rates of event-free survival compared to the patients positive for plasma hMAM mRNA. However, no significant association with overall survival was observed for expression of plasma hMAM mRNA (P = 0.16). Qualitative detection of plasma hMAM mRNA appears to be associated with unfavorable prognostic factors and lower rates of event-free survival in patients with breast cancer. Source

Jung J.-W.,Dongguk University | Kim T.H.,Gyeongsang National University | Choi H.H.,Dongguk University
IET Control Theory and Applications | Year: 2010

The authors consider the speed controller design problem for a permanent magnet synchronous motor (PMSM). Based on the Takagi-Sugeno fuzzy approach the authors design a fuzzy speed controller as well as a fuzzy load torque observer. The authors derive sufficient conditions for the existence of the controller and the observer in terms of linear matrix inequalities (LMIs). The authors give LMI parameterisations of the gain matrices. The authors also derive LMI conditions for the existence of the fuzzy speed controller and the fuzzy load torque observer guaranteeing α-stability, quadratic performance and H 2/H∞ performance. The authors implement the proposed load torque observer-based fuzzy speed control system by using a TMS320F28335 floating point DSP, and give simulation and experimental results to show the effectiveness of the proposed method. © 2010 The Institution of Engineering and Technology. Source

Choe J.-Y.,Catholic University of Daegu | Park K.-Y.,Catholic University of Daegu | Park S.-H.,Catholic University of Daegu | Lee S.-I.,Gyeongsang National University | Kim S.-K.,Catholic University of Daegu
Arthritis Research and Therapy | Year: 2012

Introduction: This study investigated whether the calcineurin inhibitor, tacrolimus, suppresses receptor activator of NF-κB ligand (RANKL) expression in fibroblast-like synoviocytes (FLS) through regulation of IL-6/Janus activated kinase (JAK2)/signal transducer and activator of transcription-3 (STAT3) and suppressor of cytokine signaling (SOCS3) signaling.Methods: The expression of RANKL, JAK2, STAT3, and SOCS3 proteins was assessed by western blot analysis, real-time PCR and ELISA in IL-6 combined with soluble IL-6 receptor (sIL-6R)-stimulated rheumatoid arthritis (RA)-FLS with or without tacrolimus treatment. The effects of tacrolimus on synovial inflammation and bone erosion were assessed using mice with arthritis induced by K/BxN serum. Immunofluorescent staining was performed to identify the effect of tacrolimus on RANKL and SOCS3. The tartrate-resistant acid phosphatase staining assay was performed to assess the effect of tacrolimus on osteoclast differentiation.Results: We found that RANKL expression in RA FLS is regulated by the IL-6/sIL-6R/JAK2/STAT3/SOCS3 pathway. Inhibitory effects of tacrolimus on RANKL expression in a serum-induced arthritis mice model were identified. Tacrolimus inhibits RANKL expression in IL-6/sIL-6R-stimulated FLS by suppressing STAT3. Among negative regulators of the JAK/STAT pathway, such as CIS1, SOCS1, and SOCS3, only SOCS3 is significantly induced by tacrolimus. As compared to dexamethasone and methotrexate, tacrolimus more potently suppresses RANKL expression in FLS. By up-regulating SOCS3, tacrolimus down-regulates activation of the JAK-STAT pathway by IL-6/sIL-6R trans-signaling, thus decreasing RANKL expression in FLS.Conclusions: These data suggest that tacrolimus might affect the RANKL expression in IL-6 stimulated FLS through STAT3 suppression, together with up-regulation of SOCS3. © 2013 Choe et al.; licensee BioMed Central Ltd. Source

Kim J.M.,Chung - Ang University | Lee H.J.,Chung - Ang University | Kim S.Y.,Gyeongsang National University | Song J.J.,Korea Research Institute of Bioscience and Biotechnology | And 2 more authors.
Applied and Environmental Microbiology | Year: 2010

To investigate the fine-scale diversity of the polyphosphate-accumulating organisms (PAO) "Candidatus Accumulibacter phosphatis" (henceforth referred to as "Ca. Accumulibacter"), two laboratory-scale sequencing batch reactors (SBRs) for enhanced biological phosphorus removal (EBPR) were operated with sodium acetate as the sole carbon source. During SBR operations, activated sludge always contained morphologically different "Ca. Accumulibacter" strains showing typical EBPR performances, as confirmed by the combined technique of fluorescence in situ hybridization (FISH) and microautoradiography (MAR). Fragments of "Ca. Accumulibacter" 16S rRNA genes were retrieved from the sludge. Phylogenetic analyses together with sequences from the GenBank database showed that "Ca. Accumulibacter" 16S rRNA genes of the EBPR sludge were clearly differentiated into four "Ca. Accumulibacter" clades, Acc-SG1, Acc-SG2, Acc-SG3, and Acc-SG4. The specific FISH probes Acc444, Acc184, Acc72, and Acc119 targeting these clades and some helpers and competitors were designed by using the ARB program. Microbial characterization by FISH analysis using specific FISH probes also clearly indicated the presence of different "Ca. Accumulibacter" cell morphotypes. Especially, members of Acc-SG3, targeted by probe Acc72, were coccobacillus-shaped cells with a size of approximately 2 to 3 μm, while members of Acc-SG1, Acc-SG2, and Acc-SG4, targeted by Acc444, Acc184, and Acc119, respectively, were coccus-shaped cells approximately 1 μm in size. Subsequently, cells targeted by each FISH probe were sorted by use of a flow cytometer, and their polyphosphate kinase 1 (ppkI) gene homologs were amplified by using a ppkl-specific PCR primer set for "Ca. Accumulibacter." The phylogenetic tree based on sequences of the ppkl gene homologs was basically congruent with that of the 16S rRNA genes, but members of Acc-SG3 with a distinct morphology comprised two different ppkl genes. These results suggest that "Ca. Accumulibacter" strains may be diverse physiologically and ecologically and represent distinct populations with genetically determined adaptations in EBPR systems. Copyright © 2010, American Society for Microbiology. All Rights Reserved. Source

Hur D.-S.,Gyeongsang National University | Kim C.-H.,Korea University | Yoon J.-S.,Inje University
Coastal Engineering | Year: 2010

Most previous investigations related to composite breakwaters have focused on the wave forces acting on the structure itself from a hydrodynamic aspect. The foundational aspects of a composite breakwater under wave-induced cyclic loading are also important in studying the stability of a composite breakwater. In this study, numerical simulations were performed to investigate the wave-induced pore water pressure and flow changes inside the rubble mound of the composite breakwater and seabed foundation. The validity and applicability of the numerical model were demonstrated by comparing numerical results with existing experimental data. Moreover, the present model clearly has shown that the instantaneous directions of pore water flow motion inside the seabed induced by surface waves are in good agreement with the general wave-induced pore water flow inside the seabed. The model is further used to discuss the stability of a composite breakwater, i.e., the interaction among nonlinear waves, composite breakwater and seabed. Numerical results suggest that the stability of a composite breakwater is affected by not only downward shear flow generating on the seaward slope face of the rubble mound but, also, a high and dense pore water pressure gradient inside the rubble mound and seabed foundation. © 2010 Elsevier B.V. Source

Extensive evidence has indicated that a high rate of cholesterol biogenesis and abnormal neuronal energy metabolism play key roles in Alzheimer’s disease (AD) pathogenesis. Here, for we believe the first time, we used osmotin, a plant protein homolog of mammalian adiponectin, to determine its therapeutic efficacy in different AD models. Our results reveal that osmotin treatment modulated adiponectin receptor 1 (AdipoR1), significantly induced AMP-activated protein kinase (AMPK)/Sirtuin 1 (SIRT1) activation and reduced SREBP2 (sterol regulatory element-binding protein 2) expression in both in vitro and in vivo AD models and in Adipo-/- mice. Via the AdipoR1/AMPK/SIRT1/SREBP2 signaling pathway, osmotin significantly diminished amyloidogenic Aβ production, abundance and aggregation, accompanied by improved pre- and post-synaptic dysfunction, cognitive impairment, memory deficits and, most importantly, reversed the suppression of long-term potentiation in AD mice. Interestingly, AdipoR1, AMPK and SIRT1 silencing not only abolished osmotin capability but also further enhanced AD pathology by increasing SREBP2, amyloid precursor protein (APP) and β-secretase (BACE1) expression and the levels of toxic Aβ production. However, the opposite was true for SREBP2 when silenced using small interfering RNA in APPswe/ind-transfected SH-SY5Y cells. Similarly, osmotin treatment also enhanced the non-amyloidogenic pathway by activating the α-secretase gene that is, ADAM10, in an AMPK/SIRT1-dependent manner. These results suggest that osmotin or osmotin-based therapeutic agents might be potential candidates for AD treatment.Molecular Psychiatry advance online publication, 22 March 2016; doi:10.1038/mp.2016.23. © 2016 Macmillan Publishers Limited Source

Kim J.K.,Kyungnam University | Cho S.Y.,Gyeongsang National University | Qin X.,Hangzhou Normal University
Acta Mathematica Scientia | Year: 2011

In this paper, we consider an iterative sequence for generalized equilibrium problems and strictly pseudocontractive mappings. We show that the iterative sequence converges strongly to a common element of the solution set of generalized equilibrium problems and of the fixed point set of strictly pseudocontractive mappings. © 2011 Wuhan Institute of Physics and Mathematics. Source

Goto M.,Oita University | Kamil K.,Oita University | Han S.Z.,Korea Institute of Materials Science | Euh K.,Korea Institute of Materials Science | And 2 more authors.
International Journal of Fatigue | Year: 2013

The crack growth direction in ultrafine-grained copper under constant stressing depends on the applied stress amplitude. The growth direction is perpendicular to the loading axis at low stresses and inclines at 45° to the loading axis at high stresses. To clarify physical causes of such different behaviors at high and low stress amplitudes, two-step fatigue stress tests are conducted. The formation mechanisms of crack paths at high and low stress amplitudes and effect of pre-stressing on subsequent crack growth direction are discussed considering the morphological features of surface-damage formed under different cyclicstress histories. © 2013 Elsevier Ltd. All rights reserved. Source

Cho S.-E.,Gyeongsang National University
Electronic Commerce Research and Applications | Year: 2010

Customer needs of geographical accessibility still plays an important role in electronic commerce, though the extent to which it does so varies according to the characteristics of products, services and the market strategies of firms. In this study, factors affecting customer needs of geographical accessibility and their structural relationships were investigated through a customer survey and statistical analysis using the methods of confirmatory factor analysis and structural equation modeling. The result shows that the three independent factors, unease of delivery, complexity of services, and trust and reliability affect significantly customer needs of geographical accessibility, with perceived risks of distant orders being a mediating factor in the relationship. © 2010 Elsevier B.V. All rights reserved. Source

Rao A.H.N.,Incheon National University | Nam S.,Gyeongsang National University | Kim T.-H.,Incheon National University
International Journal of Hydrogen Energy | Year: 2014

Crosslinked poly(arylene ether sulfone)s with pendant imidazolium units, both as crosslinkage sites and hydroxide conductors, were developed as anion exchange membranes (AEMs). These crosslinked membranes, with IECs of 0.80-1.21 meq/g, showed high hydroxide conductivity over 0.01 S/cm at 20 °C and 0.06 S/cm at 80 °C. Furthermore, the crosslinked membranes containing imidazolium groups on the side chains of the polymer exhibited good thermal, mechanical and dimensional stability, as well as excellent chemical stability at high pH. The combination of high hydroxide conductivity and low methanol permeability caused these crosslinked membranes to have very high selectivity up to 13 × 105 S s/cm3, suggesting our crosslinked membranes are suitable for DMAFCs. These membranes can also be used for various other applications including gas separations. © 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. Source

Park S.,University of North Carolina at Chapel Hill | Kim B.G.,Gyeongsang National University | Gottker-Schnetmann I.,University of Konstanz | Brookhart M.,University of North Carolina at Chapel Hill
ACS Catalysis | Year: 2012

[Ir(COE) 2Cl] 2 reacts with Et 3SiH at 23 °C to form a binuclear iridium complex (Et 3Si) 2(H) 2Ir(μ-Cl) 2Ir(H) 2(SiEt 3) 2, 1. Complex 1 reacts further with Et 3SiH at 60 °C to form a second binuclear iridium complex, Et 3Si(H) 2Ir(μ-SiEt 2) 2Ir(H) 2SiEt 3, 2, containing bridging Et 2Si groups. Activation of 2 with H 2 produces trace quantities of a very highly reactive but unobservable species which rapidly and efficiently catalyzes alkyl redistribution reactions of silanes, RR'R''SiH. D 2 and silane exchange experiments establish reactivity features of both 2 and the reactive intermediate. The intermediate cannot be observed, but it is likely a monomeric iridium silyl silylene complex that catalyzes alkyl scrambling via silane exchanges coupled with 1,3-alkyl migrations between silicon centers. DFT calculations support such a mechanism. © 2012 American Chemical Society. Source

Kang Y.,Gyeongsang National University
Journal of Preventive Medicine and Public Health | Year: 2010

Objectives: Emotional support and a stress management program should be simultaneously provided to clients as effective preventive services for healthy behavioral change. This study was conducted to review various relaxation and meditation intervention methods and their applicability for a preventive service program. Methods and results: The author of this paper tried to find various relaxation and meditation programs through a literature review and program searching and to introduce them. The 'Relaxation Response' and 'Mindfulness Based Stress Reduction (MBSR)' are the most the widely used meditative programs in mainstream medical systems. Abdominal breathing, Progressive Musclular Relaxation (PMR), Relaxative Imagery, Autogenic Training (AT) and Biofeedback are other well-known techniques for relaxation and stress management. I have developed and implemented some programs using these methods. Relaxation and meditation classes for cancer patients and a meditation based stress coping workshop are examples of this program. Conclusions: Relaxation and meditation seem to be good and effective methods for primary, secondary and tertiary preventive service programs. Program development and standardization and further study are needed for more and wider use of the mind-body approach in the preventive service area of medicine. Source

Kim Y.,Gyeongsang National University
Journal of Nanoscience and Nanotechnology | Year: 2014

In this paper, a network of small-scale robots (typically centimeter-scale robots) equipped with artificial actuators such as electric motors is considered. The purpose of this network is to have the robots keep a certain formation shape (or change to another formation shape) during maneuvers. The network has a fixed communication topology in the sense that robots have a fixed group of neighbors to communicate during maneuvers. Assuming that each robot and its actuator can be modeled as a linear system, a decentralized control law (such that each robot activates its actuator based on the information from its neighbors only) is introduced to achieve the purpose of formation keeping or change. A linear matrix inequality (LMI) for deriving the upper bound on the actuator's time constant is also presented. Simulation results are shown to demonstrate the merit of the introduced control law. Copyright © 2014 American Scientific Publishers All rights reserved. Source

Bagchi S.,Gyeongsang National University
Future Generation Computer Systems | Year: 2016

The classification of various types of processes is an important factor in large-scale distributed systems such as, grid and cloud platforms. Moreover, the coordination and control of distributed processes are research challenges in presence of unpredictable network partitioning and distributed semaphores. The process classification is important in order to allocate and schedule distributed processes enhancing overall resource utilization and throughput. The schedulers employ patterns of resource affinities of concurrent processes in order to make scheduling decisions affecting overall resource utilization in a system, where resource affinity patterns of a process may not be static. This paper proposes an estimation model and a classifier algorithm to queuing processes based on respective resource affinities. The kernel-level software architecture is designed to control scheduling of distributed processes based on classification for enhanced throughput. The classifier algorithm tracks the resource affinities of processes based on execution traces and the control algorithm performs process scheduling. Experimental results indicate that the classifier algorithm successfully manages process queues based on resource affinities of processes and, the control algorithm successfully monitors scheduler activation for a set of processes. © 2016 Elsevier B.V. All rights reserved. Source

Pospelova V.,University of Victoria | Kim S.-J.,Gyeongsang National University
Marine Micropaleontology | Year: 2010

Assemblages of organic-walled dinoflagellate cysts collected from 23 surface sediment samples distributed in shallow estuarine waters along the southern South Korean coast show high abundance and diversity. A total of 47 cyst types, representing 27 genera of three orders, were identified and distribution maps of the most common taxa have been produced. The cyst assemblages were dominated by Spiniferites (Gonyaulax cf. spinifera), Brigantedinium spp. (Protoperidinium spp.), and Dubridinium spp. (Diplopsalis spp.). Total cyst concentration varies from 1000 to 8900 cysts per gram of dry sediment, with the highest values observed in the most southern sites of the Marine Fish Ranching Ground (MFRG) of Dongdo Bay, near Saryang Island, and the Outer part of Buk Bay. The Inner Buk Bay and the south-western sites of the MFRG were recognized to be subjected to eutrophication, as indicated by the elevated proportional increase in cysts of heterotrophic species of the genera Dubridinium, Polykrikos and Protoperidinium.Cysts of HAB's causing ichthyotoxic Cochlodinium polykrikoides were not found in Buk Bay, and were otherwise found in most of the studied sites in low proportions, except in Gosung Bay where it comprised up to 41% of the cyst assemblage. This is in agreement with previously observed blooms of C. polykrikoides in Gosung Bay. © 2010 Elsevier B.V. Source

Bagchi S.,Gyeongsang National University
Lecture Notes in Artificial Intelligence (Subseries of Lecture Notes in Computer Science) | Year: 2015

The brain is a neurological device capable to carry out distributed computation and express cognition. The computational models of consciousness and cognition have potential applications in bio-inspired computing paradigm. This paper proposes a computational model of consciousness as a cognitive function following neurophysiology and elements of distributed computing. It is illustrated that the distributed computational model of consciousness has a basis in the quantum mechanical models in explaining the neurological cognitive functions. The transitions between the computing model and quantum basis are explained and analyzed considering different linear Hermitian operators. © Springer International Publishing Switzerland 2015. Source

Jung J.-W.,Dongguk University | Kim T.H.,Gyeongsang National University
Journal of Magnetics | Year: 2010

This paper introduces two types of magnetization, and reports the effect of the magnetization direction on the iron loss in a brushless DC (BLDC) motor using a 2-D time-stepped voltage source finite-element method (FEM). The iron losses were found to consist of hysteresis and eddy current loss, which were calculated from the time variation of the magnetic field distribution. To confirm the analysis, a prototype BLDC motor was constructed with a sintered ferrite magnet. The analysis and experimental results suggest that the magnetization direction has a significant effect in terms of the iron loss characteristics of the BLDC motor. © 2010 Journal of Magnetics. Source

Tantry U.S.,Sinai Center for Thrombosis Research | Bonello L.,Aix - Marseille University | Aradi D.,Heart Center Balatonfured | Price M.J.,Scripps Research Institute | And 19 more authors.
Journal of the American College of Cardiology | Year: 2013

Dual antiplatelet therapy with aspirin and a P2Y12 receptor blocker is a key strategy to reduce platelet reactivity and to prevent thrombotic events in patients treated with percutaneous coronary intervention. In an earlier consensus document, we proposed cutoff values for high on-treatment platelet reactivity to adenosine diphosphate (ADP) associated with post-percutaneous coronary intervention ischemic events for various platelet function tests (PFTs). Updated American and European practice guidelines have issued a Class IIb recommendation for PFT to facilitate the choice of P2Y 12 receptor inhibitor in selected high-risk patients treated with percutaneous coronary intervention, although routine testing is not recommended (Class III). Accumulated data from large studies underscore the importance of high on-treatment platelet reactivity to ADP as a prognostic risk factor. Recent prospective randomized trials of PFT did not demonstrate clinical benefit, thus questioning whether treatment modification based on the results of current PFT platforms can actually influence outcomes. However, there are major limitations associated with these randomized trials. In addition, recent data suggest that low on-treatment platelet reactivity to ADP is associated with a higher risk of bleeding. Therefore, a therapeutic window concept has been proposed for P2Y 12 inhibitor therapy. In this updated consensus document, we review the available evidence addressing the relation of platelet reactivity to thrombotic and bleeding events. In addition, we propose cutoff values for high and low on-treatment platelet reactivity to ADP that might be used in future investigations of personalized antiplatelet therapy. © 2013 by the American College of Cardiology Foundation. Source

Hahn J.-Y.,Sungkyunkwan University | Song Y.B.,Sungkyunkwan University | Kim E.K.,Sungkyunkwan University | Yu C.W.,Seoul National University | And 14 more authors.
Circulation | Year: 2013

BACKGROUND - : Ischemic postconditioning has been reported to reduce infarct size in patients with ST-segment-elevation myocardial infarction. However, cardioprotective effects of postconditioning have not been demonstrated in a large-scale trial. METHODS AND RESULTS - : We performed a multicenter, prospective, randomized, open-label, blinded end-point trial. A total of 700 patients undergoing primary percutaneous coronary intervention (PCI) for ST-segment-elevation myocardial infarction within 12 hours after symptom onset were randomly assigned to the postconditioning group or to the conventional primary PCI group in a 1:1 ratio. Postconditioning was performed immediately after restoration of coronary flow as follows: The angioplasty balloon was positioned at the culprit lesion and inflated 4 times for 1 minute with low-pressure (<6 atm) inflations, each separated by 1 minute of deflation. The primary end point was complete ST-segment resolution (percentage resolution of ST-segment elevation >70%) measured at 30 minutes after PCI. Complete ST-segment resolution occurred in 40.5% of patients in the postconditioning group and 41.5% of patients in the conventional PCI group (absolute difference, -1.0%; 95% confidence interval, -8.4 to 6.4; P=0.79). The rate of myocardial blush grade of 0 or 1 and the rate of major adverse cardiac events (a composite of death, myocardial infarction, severe heart failure, or stent thrombosis) at 30 days did not differ significantly between the postconditioning group and the conventional PCI group (17.2% versus 22.4% [P=0.20] and 4.3% versus 3.7% [P=0.70], respectively). CONCLUSION - : Ischemic postconditioning did not improve myocardial reperfusion in patients with ST-segment-elevation myocardial infarction undergoing primary PCI with current standard practice. CLINICAL TRIAL REGISTRATION - : URL: http://clinicaltrials.gov. Unique identifier: NCT00942500. © 2013 American Heart Association, Inc. Source

Kang Y.S.,Gyeongsang National University
Journal of the Korean Medical Association | Year: 2011

Stress management is important and various stress management methods are required in the area of clinical preventive services. Although defining stress is somewhat complicated, stress can usually be divided into two concepts, stressors and the stress reaction. Stressors are stimuli that arouse the stress reaction. Examples are disasters, life events requiring changes, and everyday hassles. The stress reaction is often called the 'fight or flight reaction' and is mediated by the sympathetic nervous system and various hormones, including cortisol and catecholamine. Stress is closely related with health behaviors and several chronic diseases. Stress is measured using biological tests or self report, including questionnaires and interviews. Psychosocial Wellbeing Index-Short Form, Brief Ecounter PsychoSocial Instrument-Korean version, Global Assessment of Recent Stress Scale, and Symptom Checklist-90-Revised are examples of questionnaires that are widely used in Korea. Stress coping methods are categorized into stimuli-oriented methods, cognitive-behavioral methods, and mind-body interventions. Relaxation and meditation are widely used mind-body medical interventions. Relaxation Response and Mindfulness-Based Stress Reduction are two of the most widely used meditative programs in the Western mainstream medical system. Abdominal breathing, Progressive Muscular Relaxation, relaxing imagery, Autogenic Training, and biofeedback are other well-known techniques for relaxation and stress management. Relaxation and meditation are effective in improving health behaviors and quality of life, and complement the treatment methods of various chronic diseases, including cardiovascular disorders and cancer. Relaxation and meditation also seem to be effective methods for use in clinical preventive services. Program development, standardization, and further study are necessary for more widespread use of mind-body interventions in the area of clinical preventive services. © Korean Medical Association. Source

Jia B.,Gyeongsang National University
Molecules and cells | Year: 2010

NADH oxidases (NOXs) catalyze the two-electron reduction of oxygen to H2O2 or four-electron reduction of oxygen to H2O. In this report, we show that an NADH oxidase from Thermococcus profundus (NOXtp) displays two forms: a native dimeric protein under physiological conditions and an oxidized hexameric form under oxidative stress. Native NOXtp displays high NADH oxidase activity, and oxidized NOXtp can accelerate the aggregation of partially unfolded proteins. The aggregates formed by NOXtp have characteristics similar to beta-amyloid and Lewy bodies in neurodegenerative diseases, including an increase of beta-sheet content. Oxidized NOXtp can also bind nucleic acids and cause their degradation by oxidizing NADH to produce H2O2. Furthermore, Escherichia coli cells expressing NOXtp are less viable than cells not expressing NOXtp after treatment with H2O2. As NOXtp shares similar features with eukaryotic cell death isozymes and life may have originated from hyperthermophiles, we suggest that NOXtp may be an ancestor of cell death proteins. Source

Choi D.S.,Gyeongsang National University | Kim M.C.,Pohang St. Marys Hospital | Lee S.K.,Lahey Clinic Medical Center | Willinsky R.A.,Toronto Western Hospital | Terbrugge K.G.,Toronto Western Hospital
Journal of Neurosurgery | Year: 2010

Object. The anatomical evolution and clinical outcome of completely coiled intracranial aneurysms after endovascular embolization have rarely been studied separately. From their prospective database, the authors reviewed follow-up angiography and clinical outcome of 87 patients whose aneurysms were designated as 100% obliterated on immediate postembolization angiography. Methods. Ninety-one aneurysms (56 ruptured and 35 unruptured) in 87 patients were included in this study. Clinical outcome was evaluated using the Glasgow Outcome Scale. Follow-up angiographic findings were assessed and categorized as 1 of the following: no recanalization, recanalization with a neck remnant, or recanalization with a body remnant. For statistical analysis, the recanalization rate was correlated with: clinical presentation; the largest aneurysm diameter, aneurysm neck size, and dome-to-neck ratio; aneurysm location; and use of special techniques such as usage of a surface modified coil, balloon remodeling technique, or stent. Results. At the latest clinical evaluation (mean 34.3 months), 81 (93.1%) of the 87 patients (91 aneurysms) had good clinical outcomes (Glasgow Outcome Scale Score 5). The procedure-related morbidity rate (permanent neurological deficit) was 2.3% (2 of 87), and there were no procedure-related deaths. On the latest follow-up angiography (mean 26.4 months), the recanalization rate was 26.4% (24 of 91 aneurysms): 16 (17.6%) with neck remnants and 8 (8.8%) with body remnants. The neck size of the recanalized aneurysms was statistically significantly larger than that of the nonrecanalized aneurysms (p = 0.006), and aneurysms with wide necks (≥ 4 mm) had a higher recanalization rate than those with a narrow neck (< 4 mm) (p = 0.002). There was no bleeding after endovascular treatment during the follow-up period. Conclusions. Completely coiled aneurysms after endovascular embolization demonstrated good clinical outcome, and there was no bleeding episode after endovascular treatment; however, there was a relatively high recanalization rate. Source

Sau A.,Gyeongsang National University
Physics of Fluids | Year: 2011

Direct numerical simulations are performed to examine roles of streamwise dynamics in the spreading and mixing of flows in a two-step rectangular sudden expansion channel. The configuration is observed to facilitate higher entrainment by virtue of developed inflow type streamwise dynamics, and the system-generated passive forcing provided the necessary impetus for sustainable growth/evolution of the vortices. In addition, with the introduction and proper placement of two tiny rectangular "tabs" over the inlet walls, the downstream growth/dynamics of the vortices could be effectively modified. Through their inflow/outflow type dynamics, the streamwise vortices are found to decisively dictate the transverse jet spreading. The physical process thereby either led to a quick axis switching of the jet, or stopped axis switching altogether. However, the stretching of the azimuthal vortices is found to remain directly linked to the streamwise continuation of jet's azimuthal curvature variation. A pressure analysis as presented herein, and the simulated nature of dynamics of two azimuthal components of vortices further reveal that the transverse pressure gradient skewing is a dominant source of streamwise vorticity in such flows. With the knowledge of simulated transverse pressure distribution, we formulate here a mechanism which efficiently predicts the inception/dynamics of all the streamwise vortices. Moreover, a novel mathematical foundation in support of the pressure analysis has been outlined here, which ensures further broader universal scope of applicability of our proposed pressure analysis. © 2011 American Institute of Physics. Source

Kang J.H.,University of Texas M. D. Anderson Cancer Center | Kang J.H.,Gyeongsang National University | Kwon J.H.,University of Texas M. D. Anderson Cancer Center | Kwon J.H.,Hallym University | And 3 more authors.
Journal of Pain and Symptom Management | Year: 2013

Context: Symptom changes are usually reported using summary statistics such as mean and/or median, which may obscure the treatment effect. Objectives: The main objective of this retrospective study was to determine the magnitude of symptom changes as assessed by the Edmonton Symptom Assessment System (ESAS) after outpatient palliative care at the first follow-up visit. Methods: We reviewed 1612 consecutive patients with cancer who were referred to the outpatient Supportive Care Center and who completed the ESAS at the initial and first follow-up visits between January 2003 and December 2010. All patients received interdisciplinary care led by the palliative care specialists following an institutional protocol. Results: The distribution of the magnitude of symptom changes was stratified by baseline intensities. Patterns were similar for different ESAS items. At the follow-up visit (median: 15 days later), 52-74% of patients showed a decrease of one or more points in the ESAS score. However, 48-80% of patients with moderate/severe intensity at baseline complained of symptoms with an ESAS score of four or more after outpatient palliative care. Symptoms with absent/mild intensity worsened, ranging from a mean of -3.04 to 0.12 at the first follow-up visit, whereas symptoms with moderate/severe intensity improved from -0.2 to 3.86 (P < 0.001). Conclusion: A considerable proportion of patients with moderate or severe intensity at baseline still had symptoms with an ESAS score of four or more. Patients with absent/mild intensities at baseline complained of symptom exacerbation at the first follow-up visit. Various strategies are needed to optimize symptom control in advanced cancer. © 2013 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved. Source

Kim W.,Gyeongsang National University | Hong T.-K.,Yonsei University | Kang T.-S.,Pukyong National University
Tectonophysics | Year: 2014

The determination of accurate hypocentral parameters is crucial in seismic monitoring, and is highly dependent on the accuracy of the implemented velocity model in conventional methods. A method to determine accurate hypocentral parameters based on an approximate velocity model is desirable. We introduce an iterative velocity updating scheme that can be readily combined with conventional hypocentral inversion methods. The algorithm searches for an optimum velocity model in a prescribed velocity range that minimizes the traveltime residuals. The hypocentral parameters are determined using the optimum velocity model. The proposed scheme reduces the dependence on a given velocity model in hypocentral inversion, providing reasonable hypocentral parameters based on an approximate velocity model. The feasibility and accuracy of the algorithm are tested with synthetic and field data. The scheme yields hypocentral parameters that are as accurate as those from full inversion methods but with approximately 70 times lower cost in terms of computational time. The proposed scheme can be readily implemented in any conventional method that is based on a fixed velocity model. © 2013 Elsevier B.V. Source

Lee N.E.,Gyeongsang National University
Korean journal of ophthalmology : KJO | Year: 2010

A previously healthy 50-year-old man was transferred to our hospital for evaluation of acute inflammation in his right eye after ocular trauma while using a grass mower. Slit lamp examination showed 1 mm-length full thickness corneal laceration without leakage, 4+ cells and inflammatory membrane in the anterior chamber, 10% hypopyon, posterior synechiae formation, and cataract change. Upon orbital computerized tomography, a metallic intraocular foreign body in the lens was identified. Vitrectomy, phacoemulsification, foreign body removal, anterior chamber irrigation, and intravitreal antibiotics injections of vancomycin and ceftazidime were performed. In a culture of humor from the anterior chamber grew Pantoea species. More procedures were performed, including intravitreal antibiotics injection of ceftazidime. Upon administering a course of intravenous ceftazidime, fortified ceftazidime and moxifloxacin eye drops, and oral prednisolone, the patient improved. Source

Peng Y.-F.,National Chi Nan University | Mittal R.,George Washington University | Sau A.,Gyeongsang National University | Hwang R.R.,Academia Sinica, Taiwan
Journal of Computational Physics | Year: 2010

In this work, the local grid refinement procedure is focused by using a nested Cartesian grid formulation. The method is developed for simulating unsteady viscous incompressible flows with complex immersed boundaries. A finite-volume formulation based on globally second-order accurate central-difference schemes is adopted here in conjunction with a two-step fractional-step procedure. The key aspects that needed to be considered in developing such a nested grid solver are proper imposition of interface conditions on the nested-block boundaries, and accurate discretization of the governing equations in cells that are with block-interface as a control-surface. The interpolation procedure adopted in the study allows systematic development of a discretization scheme that preserves global second-order spatial accuracy of the underlying solver, and as a result high efficiency/accuracy nested grid discretization method is developed. Herein the proposed nested grid method has been widely tested through effective simulation of four different classes of unsteady incompressible viscous flows, thereby demonstrating its performance in the solution of various complex flow-structure interactions. The numerical examples include a lid-driven cavity flow and Pearson vortex problems, flow past a circular cylinder symmetrically installed in a channel, flow past an elliptic cylinder at an angle of attack, and flow past two tandem circular cylinders of unequal diameters. For the numerical simulations of flows past bluff bodies an immersed boundary (IB) method has been implemented in which the solid object is represented by a distributed body force in the Navier-Stokes equations. The main advantages of the implemented immersed boundary method are that the simulations could be performed on a regular Cartesian grid and applied to multiple nested-block (Cartesian) structured grids without any difficulty. Through the numerical experiments the strength of the solver in effectively/accurately simulating various complex flows past different forms of immersed boundaries is extensively demonstrated, in which the nested Cartesian grid method was suitably combined together with the fractional-step algorithm to speed up the solution procedure. © 2010 Elsevier Inc. Source

This is the first report on the characterization and production optimization of poly-N-acetylglucosamine (PNAG) in Staphylococcus saprophyticus. A strain producing glucosamine exopolysaccharide was isolated and characterized by biochemical test and 16S rRNA gene sequence homology analysis and named as S. saprophyticus BMSZ711. The molecular mass of the purified exopolymer was about 12 kDa. Digestion of the PNAG with DispersinB proved that it has beta-1,6 linkage. BMSZ711 can only produce PNAG when grown in M1 minimal medium but not in nutrient rich medium with optimum temperature of 30 degrees C and pH of 7. Glycerol and ammonium sulfate were found to be the best carbon and nitrogen source, respectively. Maximum PNAG production was obtained when glycerol 100mM, ammonium sulfate 0.3%, yeast extract 1.5 g/L, sodium chloride 10 g/L and valine 2mM were used. Copyright 2010 Elsevier Ltd. All rights reserved. Source

Zhan J.,Hubei Institute for Nationalities | Jun Y.B.,Gyeongsang National University
Neural Computing and Applications | Year: 2010

The concept of-fuzzy interior ideals of semigroups is introduced and some related properties are investigated. In particular, we describe the relationships among ordinary fuzzy interior ideals, (∈, ∈ ∨ q)-fuzzy interior ideals and fuzzy interior ideals of semigroups. Finally, we give some characterization of [F]t by means of (∈, ∈ ∨ q)-fuzzy interior ideals. © 2009 Springer-Verlag London Limited. Source

Udomsil N.,Suranaree University of Technology | Rodtong S.,Suranaree University of Technology | Choi Y.J.,Gyeongsang National University | Hua Y.,Suranaree University of Technology | Yongsawatdigul J.,Suranaree University of Technology
Journal of Agricultural and Food Chemistry | Year: 2011

The potential of Tetragenococcus halophilus as a starter culture for flavor improvement in fish sauce fermentation was elucidated. Four strains of T. halophilus isolated from fish sauce mashes were inoculated to anchovy mixed with 25% NaCl with an approximate cell count of 10 6 CFU/mL. The α-amino content of 6-month-old fish sauce samples inoculated with T. halophilus was 780-784 mM. The addition of T. halophilus MRC10-1-3 and T. halophilus MCD10-5-10 resulted in a reduction of histamine (P < 0.05). Fish sauce inoculated with T. halophilus showed high contents of total amino acids with predominantly high glutamic acid. Major volatile compounds in fish sauce were 2-methylpropanal, 2-methylbutanal, 3-methylbutanal, and benzaldehyde. T. halophilus-inoculated fish sauce samples demonstrated the ability to reduce dimethyl disulfide, a compound contributing to a fecal note. The use of T. halophilus for fish sauce fermentation improves amino acid profiles and volatile compounds as well as reduces biogenic amine content of a fish sauce product. © 2011 American Chemical Society. Source

Wang Y.,University of Technology, Sydney | Sun B.,University of Technology, Sydney | Park J.,Gyeongsang National University | Kim W.-S.,Daejung Energy Materials Co. | And 2 more authors.
Journal of Alloys and Compounds | Year: 2011

Nanosize carbon coated LiFePO4 cathode material was synthesized by in situ polymerization. The as-prepared LiFePO4 cathode material was systematically characterized by X-ray diffraction, thermogravimetric- differential scanning calorimetry, X-ray photo-electron spectroscopy, field-emission scanning electron microscopy, and transmission electron microscopy techniques. Field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) images revealed that the morphology of the LiFePO4 consists of primary particles (40-50 nm) and agglomerated secondary particles (100-110 nm). Each particle is evenly coated with an amorphous carbon layer, which has a thickness around 3-5 nm. The electrochemical properties were examined by cyclic voltammetry and charge-discharge testing. The as-prepared LiFePO4 can deliver an initial discharge capacity of 145 mAh/g, 150 mAh/g, and 134 mAh/g at 0.2 C, 1 C, and 2 C rates, respectively, and exhibits excellent cycling stability. At a higher C-rate (5 C) a slight capacity loss could be found. However after being charge-discharge at lower C-rates, LiFePO4 can be regenerated and deliver the discharge capacity of 145 mAh/g at 0.2 C. © 2010 Elsevier B.V. All rights reserved. Source

Woo S.H.,Gyeongsang National University
Journal of Laparoendoscopic and Advanced Surgical Techniques | Year: 2014

Objective: Natural orifice translumenal endoscopic surgery (NOTES ®; American Society for Gastrointestinal Endoscopy [Oak Brook, IL] and Society of American Gastrointestinal and Endoscopic Surgeons [Los Angeles, CA]) has generated excitement among surgeons as potentially scar-free surgery. We developed this technique while taking into consideration that it could also be applied to transoral thyroid surgery. Patient and Methods: We report the case of a 35-year-old woman with a 0.5×0.5-cm papillary thyroid microcarcinoma. We implemented a modified approach for the removal of the thyroid by using a frenotomy incision of the mouth, accompanied by an endoscope system. Results: A modified approach for the removal of the thyroid was used on the patient. The total operating time was 120 minutes, and there were no specific complications. The patient continues to be free of any diseases 12 months after the excision. Conclusions: Thyroidectomy can be performed by a transoral endoscope-assisted approach through a frenotomy incision of the mouth. We describe the detailed procedures for an endoscope-assisted transoral thyroidectomy using a frenotomy incision. © 2014, Mary Ann Liebert, Inc. Source

Kadam A.A.,Shivaji University | Telke A.A.,Gyeongsang National University | Jagtap S.S.,Konkuk University | Govindwar S.P.,Shivaji University
Journal of Hazardous Materials | Year: 2011

The objective of this study was to develop consortium using Pseudomonas sp. SUK1 and Aspergillus ochraceus NCIM-1146 to decolorize adsorbed dyes from textile effluent wastewater under solid state fermentation. Among various agricultural wastes rice bran showed dye adsorption up to 90, 62 and 80% from textile dye reactive navy blue HE2R (RNB HE2R) solution, mixture of textile dyes and textile industry wastewater, respectively. Pseudomonas sp. SUK1 and A. ochraceus NCIM-1146 showed 62 and 38% decolorization of RNB HE2R adsorbed on rice bran in 24. h under solid state fermentation. However, the consortium of Pseudomonas sp. SUK1 and A. ochraceus NCIM-1146 (consortium-PA) showed 80% decolorization in 24. h. The consortium-PA showed effective ADMI removal ratio of adsorbed dyes from textile industry wastewater (77%), mixture of textile dyes (82%) and chemical precipitate of textile dye effluent (CPTDE) (86%). Secretion of extracellular enzymes such as laccase, azoreductase, tyrosinase and NADH-DCIP reductase and their significant induction in the presence of adsorbed dye suggests their role in the decolorization of RNB HE2R. GCMS and HPLC analysis of product suggests the different fates of biodegradation of RNB HE2R when used Pseudomonas sp. SUK1, A. ochraceus NCIM-1146 and consortium PA. © 2011 Elsevier B.V. Source

Goto M.,Oita University | Kamil K.,Oita University | Han S.Z.,Korea Institute of Materials Science | Euh K.,Korea Institute of Materials Science | And 2 more authors.
International Journal of Fatigue | Year: 2013

To clarify the effects of grain refinement on the growth behavior of small surface cracks, fatigue tests on round bar specimens were conducted on coarse-grained (CG) copper and ultrafine-grained (UFG) copper processed with equal channel angular pressing. The growth behavior of a small crack was monitored using a plastic replication technique. The difference in the growth behavior tendency between the CG and UFG copper occurred at an extremely low fatigue crack growth rate (FCGR) of dl/dN < 10-6 mm/cycle. For the UFG copper, the FCGR temporarily dropped at around dl/dN = 3 × 10 -7 mm/cycle and then gradually recovered with subsequent cycling. After the FCGR exceeded dl/dN = 10-6 mm/cycle, it was nearly proportional to the crack length. On the other hand, the FCGR of the CG copper showed no temporary drop but rather increased steadily with cycling. To understand the reason for the temporary decrease of the FCGR of UFG copper, a crack growth model based on the reversible plastic zone size at a crack tip and the related microstructural factors were developed. In addition, FCGR evaluation was discussed by applying σanl (σa, nominal stress amplitude; l, crack length; n, material constant) to both materials. © 2012 Elsevier Ltd. All rights reserved. Source

Nagarathinam M.,National University of Singapore | Saravanan K.,National University of Singapore | Phua E.J.H.,National University of Singapore | Reddy M.V.,National University of Singapore | And 3 more authors.
Angewandte Chemie - International Edition | Year: 2012

MOP(OF) up the lithium: Metal organic-phosphate open framework materials, for example K 2.5[(VO) 2(HPO 4) 1.5(PO 4) 0.5(C 2O 4)] (see scheme), are investigated as hybrid cathode materials for lithium ion batteries. The redox-active metal center, robustness, available two-dimensional migration pathways in the abplane, and cavities along the caxis for the migration of the alkali metal ions allow the rapid insertion and extraction of alkali metal ions. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Kim B.,Gyeongsang National University
Journal of Institute of Control, Robotics and Systems | Year: 2013

In this paper Legendre wavelets are used to approximate the solutions of linear time-invariant system. The Legendre wavelet and its integral operational matrix are presented and an efficient algorithm to solve the Sylvester matrix equation is proposed. The algorithm is based on the decomposition of the Sylvester matrix equation and the preorder traversal algorithm. Using the special structure of the Legendre wavelet's integral operational matrix, the full order Sylvester matrix equation can be solved in terms of the solutions of pure algebraic matrix equations, which reduce the computation time remarkably. Finally a numerical example is illustrated to demonstrate the validity of the proposed algorithm. © ICROS 2013. Source

Hong C.O.,South Dakota State University | Chung D.Y.,Chungnam National University | Lee D.K.,Urbana University | Kim P.J.,Gyeongsang National University
Archives of Environmental Contamination and Toxicology | Year: 2010

A study was conducted to compare the effects of phosphate (P) materials in reducing cadmium extractability. Seven P materials (commercial P fertilizers - fused phosphate (FP), 'fused and superphosphate' [FSP], and rock phosphate [RP]; P chemicals-Ca[H2PO4]2.H2O, [NH4]2.HPO4, KH2PO4, and K2HPO4) were selected for the test. The selected P source was mixed with Cd-contaminated soil at the rate of 0, 200, 400, 800, and 1,600 mg P kg-1 under controlled moisture conditions at 70% of water holding capacity, then incubated for 8 weeks. FP, Ca(H2PO 4)2.H2O, KH2PO4, and K2HPO4 significantly decreased NH 4OAcextractable Cd (plant-available form) concentrations with increasing application rates. Compared to other phosphate materials used, K 2HPO4 was found to be the most effective in reducing the plant-available Cd concentration in soil, mainly due to the negative charge increase caused by soil pH and phosphate adsorption. Contrary to the general information, FSP and (NH4)2HPO4 increased Cd extractability at low levels of P application (<400 mg kg-1), and thereafter Cd extractability decreased significantly with increasing application rate. RP scarcely had an effect on reducing Cd extractability. Ion activity products of CdHPO4, Cd(OH)2, and CdCO3 analyzed by the MINTEQ program were significantly increased by K2HPO 4 addition, but the effect of Cd-P compound formation on reducing Cd extractability was negligible. Conclusively, the P-induced alleviation of Cd extractability can be attributed primarily to Cd immobilization due to the increase in soil pH and negative charge rather than Cd-P precipitation, and therefore, alkaline P materials such as K2HPO4 are effective for immobilizing soil Cd. ©Springer Science+Business Media, LLC 2009. Source

Moon S.C.,Korea Institute of Materials Science | Kim J.Y.,Korea Institute of Industrial Technology | Oh B.T.,Gyeongsang National University
Polymer Engineering and Science | Year: 2014

Ochre (Oc), with its high absorption and viscous properties and presence of several inorganic components, was incorporated in a polycarbonate-unmodified carbon nanotubes using processing methods such as electrospinning and compression molding, to produce strong and flame resistant composites with biaxially oriented nanomaterials. These composites were found to have good mechanical properties (ultimate tensile strength of ∼95.3 MPa) and flame resistance (∼464 J g-1K-1 heat release capacity) when ∼1 wt% of single-walled carbon nanotubes was used with 2.5 wt% Oc, which was used as a compatibilizer and flame retardant. POLYM. ENG. SCI., 54:1289-1299, 2014. © 2013 Society of Plastics Engineers © 2013 Society of Plastics Engineers. Source

Wang G.,University of Technology, Sydney | Liu H.,University of Queensland | Liu J.,University of Queensland | Qiao S.,University of Queensland | And 3 more authors.
Advanced Materials | Year: 2010

Hexagonally ordered mesoporous LiFePO4/C nanocomposites can be synthesised with LiFePO4 nanoparticles embedded in an interconnected carbon framework. Mesoporous LiFePO4/C nanocomposites exhibit superior electrochemical performance and ultra-high specific power density, which makes this architecture suitable for high power applications such as HEVs and stationary energy storage for smart grids. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Park M.N.,Jinju Health College | Choi S.Y.,Gyeongsang National University
Journal of Korean Academy of Nursing | Year: 2014

Purpose: This study was done to develop a reproductive health program to improve reproductive health of women immigrants. Methods: The participants in the study were 58 immigrant women who lived in Vietnam, China, Philippines, or Cambodia before marriage. They were assigned to the experiment group (n= 29) or the control group (n= 29). The reproductive health program for this study consisted of reproductive health education, health counseling, phone monitoring, and emotional support based on Cox (1982)'s Interaction Model of Client Health Behavior and was implemented for four weeks. Results: There were significant differences in reproductive health knowledge (t= 9.78, p<.001), reproductive health attitude (t= 6.59, p<.001), and reproductive health behavior (t= 5.11, p<.001) within and between groups after the reproductive health program. But there were no significant differences in clinical indicators between the two groups. Conclusion: The results of this study indicate the that reproductive health program for the women immigrants is effective in terms of reproductive health knowledge, reproductive health attitude and reproductive health behaviors. Therefore, nurses in public and private facilities, such as multicultural centers and public health centers in each community, should develop strategies to expand and provide reproductive health programs for women immigrants. © 2014 Korean Society of Nursing Science. Source

Chung W.S.,Gyeongsang National University
International Journal of Theoretical Physics | Year: 2015

In this paper we consider the case of only space-space non-commutativity in two dimension. We also discuss the Rydberg atom model in this space and use the linear realization of the coordinate and momentum operators to solve the Schrödinger equation for the Rydberg atom through the standard perturbation method. Finally, the thermodynamics for the Rydberg atom model is discussed. © 2014, Springer Science+Business Media New York. Source

Choi S.H.,Gyeongsang National University | Jeong Y.-S.,Rutgers University | Jeong M.K.,Rutgers University | Jeong M.K.,KAIST
IEEE Transactions on Systems, Man and Cybernetics Part C: Applications and Reviews | Year: 2010

Most recommendation algorithms attempt to alleviate information overload by identifying which items a user will find worthwhile. Content-based (CB) filtering uses the features of items, whereas collaborative filtering (CF) relies on the opinions of similar customers to recommend items. In addition to these techniques, hybrid methods have also been suggested to improve the performance of recommendation algorithms. However, even though recent hybrid methods have helped to avoid certain limitations of CB and CF, scalability and sparsity are still major problems in large-scale recommendation systems. In order to overcome these problems, this paper proposes a novel hybrid recommendation algorithm HYRED, which combines CF using the modified Pearsons binary correlation coefficients with CB filtering using the generalized distance-to-boundary-based rating. In the proposed recommendation system, the nearest and farthest neighbors of a target customer are utilized to yield a reduced dataset of useful information by avoiding scalability and sparsity problem when confronted by tremendous volumes of data. The use of reduced datasets enables us not only to lessen the computing effort, but also to improve the performance of recommendations. In addition, a generalized method to combine CF and CB system into a hybrid recommendation system is proposed by developing on the normalization metric. We have used this HYRED algorithm to experiment with all possible combination of CF and statistical-learning-based CB filtering. These experiments have shown that the use of reduced datasets saves computational time, and neighbor information improves performance. © 2010 IEEE. Source

Jeong M.-Y.,Gyeongsang National University | Wu J.W.,Ewha Womans University
Japanese Journal of Applied Physics | Year: 2012

We realized the fabrication of a temporally stabilized continuously tunable laser device using a UV-curable polymerized dye-doped cholesteric liquid crystal wedge cell. The spatial tuning resolution was less than 1 nm over a 70 nm spectral range. The continuous tuning behavior of the polymerized wedge cholesteric liquid crystal (CLC) cell is due to the fact that the concentration of the pitch gradient matches the helical pitch determined by the cell thickness. After about 1 year had elapsed, the spectral range of continuous laser tuning was nearly maintained in the polymerized CLC wedge cells. This scheme raises the possibility of practical applications of the CLC laser device, which allows for a wide tunability of single-mode laser emissions. © 2012 The Japan Society of Applied Physics. Source

Cho S.-Y.,Gyeongsang National University | Cho C.-H.,Suntech Co.
Renewable Energy | Year: 2015

Thermal properties of the available energy such as maximum temperature and thermal energy capacity are greatly influenced to the design of energy conversion system like the organic Rankine cycle (ORC). Useful thermal energy can be obtained from: waste heat energy, geothermal energy, solar heat energy, biomass energy, and so on. However, these cannot usually be supplied at constant levels. Hence, the temperature and flowrate of the thermal energy can vary while the ORC is working. In order to efficiently utilize such fluctuating thermal energy, an experimental study was conducted while adjusting the mass flowrate and the temperature of the working fluid. Three supersonic nozzles and an impulse type turbine were applied. The supersonic nozzle was adopted to increase the spouting velocity for efficient operation of the impulse turbine. The nozzle was designed to reach a velocity of Mach 1.6 at the nozzle exit, and three nozzles were used to control the mass flowrate in this experiment. The experimental results were compared with the predicted results obtained by the cycle analysis. © 2015 Elsevier Ltd. Source

Park K.-W.,Gyeongsang National University | Seo H.J.,Chonnam National University | Kwon O.-Y.,Chonnam National University
Microporous and Mesoporous Materials | Year: 2014

Mesoporous silica-pillared H+-titanosilicate (SPT) was prepared by hydrolysis of tetraethylorthosilicate using dodecylamine as the template and catalyst in the interlayer space of H+-titanosilicate (H 4Ti2Si8O22·4H2O). SPT exhibited regular gallery height of 3.60 nm, narrow pore distributions of 3.1-3.4 nm, and a large specific surface area of 435-542 m2/g. The sharpness of the SPT 2d00l peak was well preserved even after heating for 5 h at 800 °C in air. Ni/STP and Rh/SPT loaded with 5 wt% metal were examined for partial oxidation of methane (POM) at 700 °C. Ni/SPT and Rh/SPT maintained stable activity for almost 100 h on stream. CH4 conversion (>90%) and H2 yield (>90%) over Ni/SPT and Rh/SPT were higher than that (>80%) of commercial Rh/Al2O3 (loaded with 5 wt% metal). CO yield was very low due to carbon cocking from the formation of carbon nanotubes. Transmission electron microscopy images of the STP catalysts exhibited uniform spacing between the layers even after catalysis and uniform dispersion of metal particles. These observations indicate the unique properties of an SPT catalyst such as the existence of five-coordinated titanium(VI) as an oxidation site, uniform dispersion of metal, ordered pore structure and heat stability, resulting in good performance during POM. © 2014 Published by Elsevier Inc. Source

Yoon J.,Gyeongsang National University | Park J.,Gwangju Institute of Science and Technology | Ryu J.,Gwangju Institute of Science and Technology
International Journal of Robotics Research | Year: 2010

In this paper we describe a planar symmetric walking cancellation algorithm for generating smooth and collision-free turning motions on the foot-platform locomotion interface, the Virtual Walking Machine that has two three-degree-of-freedom (DOF) planar and three-DOF footpad parallel manipulators connected in series. This solves the problem of the asymmetric walking velocity profile of the swing and stance feet in the existing constant-velocity walking cancellation method. The proposed symmetric walking cancellation method cancels the stance foot motion with the opposite swing foot motion. In addition, the proposed walking cancellation method was extended to a planar walking algorithm that uses constraint motions of curvatures to avoid mechanical collisions between the two foot platforms. Walking simulations, experiments, and user evaluations showed that the proposed symmetric walking cancellation algorithm is better than the previous constant-velocity algorithm in terms of smoothness, absence of delay, and walking stability. For planar motions, the device can generate a maximum turning angle of 20 ° and a maximum turning velocity of 45 ° per second for one step with a minimum available curvature of 1 m. Navigation experiments in a virtual environment were performed to show the effectiveness of the suggested planar walking algorithm. Source

The effects of actively stimulating devices (ASD) on juvenile flatfish escape were studied to increase escape rates from the cod end by encouraging fish to approach the net wall. Two kinds of ASD were designed: a fluttering net panel, i.e., a free-end flag-like net panel, and a double conical rope array. Escape responses of juvenile bastard halibut were observed in a circulating water channel using two model cod ends, one made with diamond-shaped 43-mm-mesh-size polyethylene (PE) as a high-contrast cod end and the other with polyamid (PA) mono-ply as a low-contrast cod end. Retention rate was significantly lower with the double conical rope-array ASD in the PE cod end than with conventional PE cod ends only or the fluttering net-panel ASD inside the PE cod end. Mean retention rate with the low-contrast PA cod end was also significantly lower than that with the high-contrast PE conventional cod end. Therefore, active fluttering devices using a double conical rope array together with less visible low-contrast netting in the cod end could help to reduce the bycatch of juvenile flatfish by weakening their optomotor response and actively driving fish to the side net panel. Source

Chung W.S.,Gyeongsang National University
International Journal of Geometric Methods in Modern Physics | Year: 2016

In this paper, we consider a truncated harmonic oscillator without reflection symmetry and a truncated harmonic oscillator with reflection symmetry. For both algebra, we investigate the representation, correct Hamiltonian and uncertainty relation. Especially, for a truncated harmonic oscillator with reflection symmetry, we discuss thermodynamics of a particle obeying this algebra. © 2016 World Scientific Publishing Company. Source

Bagchi S.,Gyeongsang National University
Future Generation Computer Systems | Year: 2011

The group communication algorithms are employed in fault-tolerant distributed computing systems, where the members of a group coordinate by using multicast messages. The messages need to be totally ordered at the nodes in order to maintain global consistency among the nodes. In the large scale distributed systems having replicated servers, the asynchronous as well as simultaneous group communication mechanism is required. This paper proposes a distributed algorithm intended to unidirectional virtual ring for asynchronous and simultaneous group communication in a close group maintaining totally ordered as well as atomic communication. The algorithm is easy to implement and computationally inexpensive having reduced overall message complexity. The algorithm is implemented in distributed system setup in large scale and the experimental results illustrate that algorithm is scalable, where the message complexity per node is comparatively lower. This paper describes the design, analysis and experimental validation of the algorithm. © 2010 Elsevier B.V. All rights reserved. Source

Bagchi S.,Gyeongsang National University
Communications in Computer and Information Science | Year: 2016

In recent times, an alternate approach to model and analyze distributed computing systems has gained research attention. The alternate approach considers higher-dimensional topological spaces and homotopy as well as homology while modeling and analyzing asynchronous distributed computing. This paper proposes that the monotone spaces having ending property can be effectively employed to model and analyze consistency and convergence of distributed computing. A set of definitions and analytical properties are constructed considering monotone spaces. The inter-space relationship between simplexes and monotone in topological spaces is formulated. © Springer International Publishing Switzerland 2016. Source

Lew D.H.,Gyeongsang National University
The Korean journal of gastroenterology = Taehan Sohwagi Hakhoe chi | Year: 2013

Several studies reported a subgroup of gastric cancer patients showing elevated serum alpha-fetoprotein (AFP) at the time of diagnosis. We investigated the clinicopathological characteristics and prognostic factors of AFP producing gastric cancer (AFPPGC) by comparing with AFP non-producing gastric cancer (AFPNPGC). A total of 909 patients were diagnosed with gastric cancer from January 2005 to March 2013 at Gyeongsang National University Hospital and their AFP levels were measured at the time of diagnosis. After excluding 138 patients with underlying liver diseases, 34 patients with elevated serum AFP level over 10 mg/mL were assigned to AFPPGC group and the remaining 737 patients with serum level of AFP below 10 ng/mL were assigned to AFPNPGC group. Results: The median survival length was shorter in AFPPGC group than AFPNPGC group (18.3 ± 25.5 months vs. 30.0 ± 22.0 months, p=0.004). The incidence of liver metastasis (47.1% vs. 3.3%, p<0.001) and lymph node metastasis (91.2% vs. 31.6%, p<0.001) was significantly higher in AFPPGC group. The probability of encountering metachronous liver metastasis after the operation was higher in AFPPGC group (44.4% vs. 2.0%, p<0.001). Multivariate analysis revealed that patients in the AFPPGC group who received chemotherapy (p=0.037) or underwent operation (p=0.001) had a better survival rate. Conclusions: AFPPGC behaves more aggressively and shows a worse prognosis. Therefore, serum AFP level should be routinely checked in all patients diagnosed with gastric cancer. Source

Kim G.C.,Pusan National University | Lee H.W.,Pohang University of Science and Technology | Byun J.H.,Gyeongsang National University | Chung J.,Pusan National University | And 2 more authors.
Plasma Processes and Polymers | Year: 2013

Oral cavity and teeth are important organs of human body. The attention and cost for dental treatments increase every year. In dental clinics, the most common diseases are dental caries, periodontal disease, and stomatitis. Dental aesthetics such as tooth whitening is one of important part of dental clinics. However, conventional treatment methods in dental clinics have limitations by pain and long-time treatment. Nonthermal plasmas have shown great potential as noble techniques to dental applications due to safety and multi-functional effects achieved by the abundant plasma components including charged particles, radiation, and reactive species. Reactive oxygen species generated from plasmas can effectively inhibit pathogen activity. The use of nonthermal plasmas is efficient in treating oral diseases because the construction of the plasma devices allows easy access to the oral cavity. However, few studies have been conducted on the use of plasmas in oral disease. Tooth aesthetics, as well as treatment of oral diseases, are important in determining the quality of human life. Recent studies have shown nonthermal plasmas to have strong tooth-bleaching effects. Studies on oral care using nonthermal plasmas will significantly contribute to oral health in the future. Dental applications of nonthermal atmospheric pressure plasmas (NAPP) are reviewed in this paper. Oral diseases are caused by anaerobic or oxygen-sensitive pathogenic microorganisms. NAPP are efficient in treating oral diseases due to their components, mainly reactive oxygen species; moreover NAPP have been recently shown to have strong tooth-bleaching effects. Continuing research on oral care using NAPP will contribute to improving oral health in the future. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source