Awad-Allah M.F.,National Research Center of Egypt |
Yasufuku N.,Kyushu University |
Mariandhar S.,International Science and Technology University
Lowland Technology International | Year: 2017
In this paper, a set of small-scale laboratory single flexible pile model was conducted in a medium dense Toyoura sand environment under the effect of cyclic lateral loads. Digital images were captured for the plastic deformations of the soil during the lateral loading from the top of the testing chamber. Combination of photo image analysis and analytical cyclic p-y curve methods was implemented for estimating the three dimensional (3D) failure zone adjacent to pile shaft. The 3D failure pattern of the soil around single pile shaft was investigated through two steps, including: (1) determination of the range of lateral plastic deformations at the top of ground surface in perpendicular and parallel directions of cyclic loads; and (2) determination of the point of rotation (zero displacement) along the pile shaft. Experimental results showed that a conical passive zone of plastic deformations is established around pile shaft due to applying two-way lateral cyclic loading at pile head. Based on the findings, design considerations for piles subjected to lateral cyclic loading have been introduced.
Wang X.,Princeton University |
Ullrich R.,International Science and Technology University |
Hofrichter M.,International Science and Technology University |
Groves J.T.,Princeton University
Proceedings of the National Academy of Sciences of the United States of America | Year: 2015
A kinetic and spectroscopic characterization of the ferryl intermediate (APO-II) from APO, the heme-thiolate peroxygenase from Agrocybe aegerita, is described. APO-II was generated by reaction of the ferric enzyme with metachloroperoxybenzoic acid in the presence of nitroxyl radicals and detected with the use of rapid-mixing stopped-flow UV-visible (UV-vis) spectroscopy. The nitroxyl radicals served as selective reductants of APO-I, reacting only slowly with APO-II. APO-II displayed a split Soret UV-vis spectrum (370 nm and 428 nm) characteristic of thiolate ligation. Rapid-mixing, pH-jump spectrophotometry revealed a basic pKa of 10.0 for the FeIV-O-H of APO-II, indicating that APO-II is protonated under typical turnover conditions. Kinetic characterization showed that APO-II is unusually reactive toward a panel of benzylic C-H and phenolic substrates, with second-order rate constants for C-H and O-H bond scission in the range of 10-107 M-1·s-1. Our results demonstrate the important role of the axial cysteine ligand in increasing the proton affinity of the ferryl oxygen of APO intermediates, thus providing additional driving force for C-H and O-H bond scission. © 2015, National Academy of Sciences. All rights reserved.
Tran T.M.,National Institute of Allergy and Infectious Diseases |
Aghili A.,National Institute of Allergy and Infectious Diseases |
Li S.,National Institute of Allergy and Infectious Diseases |
Ongoiba A.,International Science and Technology University |
And 4 more authors.
Malaria Journal | Year: 2014
Background: As public health efforts seek to eradicate malaria, there has been an emphasis on eliminating low-density parasite reservoirs in asymptomatic carriers. As such, diagnosing submicroscopic Plasmodium infections using PCR-based techniques has become important not only in clinical trials of malaria vaccines and therapeutics, but also in active malaria surveillance campaigns. However, PCR-based quantitative assays that rely on nucleic acid extracted from dried blood spots (DBS) have demonstrated lower sensitivity than assays that use cryopreserved whole blood as source material.Methods. The density of Plasmodium falciparum asexual parasites was quantified using genomic DNA extracted from dried blood spots (DBS) and the sensitivity of two approaches was compared: quantitative real-time PCR (qPCR) targeting the P. falciparum 18S ribosomal RNA gene, either with an initial conventional PCR amplification prior to qPCR (nested qPCR), or without an initial amplification (qPCR only). Parasite densities determined by nested qPCR, qPCR only, and light microscopy were compared.Results: Nested qPCR results in 10-fold higher sensitivity (0.5 parasites/μl) when compared to qPCR only (five parasites/ul). Among microscopy-positive samples, parasite densities calculated by nested qPCR correlated strongly with microscopy for both asymptomatic (Pearson's r = 0.58, P < 0.001) and symptomatic (Pearson's r = 0.70, P < 0.0001) P. falciparum infections.Conclusion: Nested qPCR improves the sensitivity for the detection of P. falciparum blood-stage infection from clinical DBS samples. This approach may be useful for active malaria surveillance in areas where submicroscopic asymptomatic infections are prevalent. © 2014 Tran et al.; licensee BioMed Central Ltd.
Tanrikulu C.,International Science and Technology University
Journal of Environmental Protection and Ecology | Year: 2014
The aim of this study was to examine the sex and the gender identity difference in the environmental concern, perceived consumer effectiveness, and green purchase behaviour in consumers. Data were collected from consumers from region of TR62 in Turkey via self-administered questionnaire. The findings suggested that there was no difference between sex groups in terms of environmental concern, perceived consumer effectiveness, and green purchase behaviour, however, there were differences between gender identity groups in terms of them. The major contribution of this study for literature and practitioners is to fill the gap in determining the gender identity difference of consumers. The findings were discussed, and suggestions were provided for theory and administration.
Cabuk S.,Cukurova University |
Tanrikulu C.,International Science and Technology University |
Gelibolu L.,Kafkas University
International Journal of Consumer Studies | Year: 2014
The aim of this research was to examine the effect of health consciousness, environmental concern and food safety concern on both the intention to buy organic foods and the attitude towards organic foods, and the effect of attitude towards organic foods on the intention to buy organic foods. It had also a specific aim to explore whether attitude has a mediation effect on the relationship between the intention to buy and health consciousness, environmental concern and food safety concern. Data were gathered from consumers using a survey. The questionnaire used was administered to a convenience sample of 385 consumers from Adana, Turkey, through a self-administered questionnaire. Regression and mediation analysis were used to test the hypotheses. The findings suggested that the attitude and the intention to buy were affected by health consciousness, environmental concern and food safety concern. They also showed that the attitude plays a fundamental role both in terms of the direct impact on the intention to buy and the indirect effect as a mediator on how the health consciousness, environmental concern and food safety concern affect the intention to buy. This research is useful to fill the gaps in the literature regarding the mediation effect of the attitude on the relationship between the intention to buy and food safety concern. Another contribution is being one of the first to examine the attitude as a mediator on the relationship between the intention to buy organic foods and health consciousness, environmental concern and food safety concern of Turkish consumers. © 2014 John Wiley & Sons Ltd.
Viju N.,International Science and Technology University |
Satheesh S.,International Science and Technology University |
Satheesh S.,King Abdulaziz University |
Vincent S.G.P.,International Science and Technology University
Saudi Journal of Biological Sciences | Year: 2013
In this study, antibiofilm activity of coconut husk extract (CHE) was tested by various assays in the laboratory. The effects of CHE on extracellular polymeric substance (EPS) production, hydrophobicity and adhesion ability of Pseudomonas sp., Alteromonas sp. and Gallionella sp. and the antimicrobial activity of the extract against these bacteria were assessed. CHE was found to possess antibacterial activity against all the bacterial strains and affected the EPS production. The CHE affected the growth of the biofilm-forming bacteria in a culture medium. The hydrophobicity of the bacterial cells was also changed due to the CHE treatment. The active compound of the CHE was characterised by thin-layer chromatography (TLC), high performance liquid chromatography (HPLC) and fourier transform infrared (FT-IR) analysis. HPLC spectrum showed a single peak and the FT-IR spectrum indicated the presence of an OH-group-containing compound in the extract. In conclusion the CHE could be used as a source for the isolation of antifouling compounds. © 2012.
Lazakis I.,University of Strathclyde |
Turan O.,University of Strathclyde |
Aksu S.,International Science and Technology University
Ships and Offshore Structures | Year: 2010
Ship maintenance was initially considered as more of a financial burden than as a way to preserve safety, environment and quality transportation. The benefits from applying a sound and systematic maintenance policy are emerging both in the minimisation of unnecessary downtime as well as in the increase of operational capability. In this paper, a novel predictive maintenance strategy is demonstrated, combining the existing ship operational and maintenance tasks with the advances stemming from new applied techniques. The initial step for the application of the above-mentioned strategy is also shown regarding the machinery space of a cruise ship. Well-known tools are applied such as Failure Modes, Effects and Criticality Analysis (FMECA) and Fault Tree Analysis (FTA). Outcomes of this study are the identification of the critical components of the system, the estimation of the reliability of the overall system and sub-systems, the prioritisation of the maintenance tasks and finally the availability of the specific end events/items. © 2010 Taylor & Francis.
Tsao C.-C.,Sudan University of Science and Technology |
Wu W.-W.,International Science and Technology University
International Journal of Computer Integrated Manufacturing | Year: 2014
In highly competitive manufacturing technologies nowadays, delamination-free hole is expected for composite components using innovative designed tools and optimised drilling parameters due to increase in composite structure production and in the need for higher quality machining. An empirical study successfully applies the proposed fuzzy decision-making trial and evaluation laboratory (DEMATEL) to understand the causal influence of the various tool materials and geometries, as well as machining parameters, in drilling composites using compound special-core drill. The obtained result shows that feed rate is the most important factor in innovative project of tool research and design within the cause group. However, cutting velocity ratio, thickness of outer drill, stretch and grit size of diamond have the best effect on machined parameter selection during drilling composites using compound special-core drills. © 2014 © 2014 Taylor & Francis.
Obeng-Adjei N.,National Institute of Allergy and Infectious Diseases |
Portugal S.,National Institute of Allergy and Infectious Diseases |
Tran T.M.,National Institute of Allergy and Infectious Diseases |
Tran T.M.,Indiana University |
And 10 more authors.
Cell Reports | Year: 2015
Malaria-specific antibody responses are short lived in children, leaving them susceptible to repeated bouts of febrile malaria. The cellular and molecular mechanisms underlying this apparent immune deficiency are poorly understood. Recently, T follicular helper (Tfh) cells have been shown to play a critical role in generating long-lived antibody responses. We show that Malian children have resting PD-1+CXCR5+CD4+ Tfh cells in circulation that resemble germinal center Tfh cells phenotypically and functionally. Within this population, PD-1+CXCR5+CXCR3- Tfh cells are superior to Th1-polarized PD-1+CXCR5+CXCR3+ Tfh cells in helping B cells. Longitudinally, we observed that malaria drives Th1 cytokine responses, and accordingly, the less-functional Th1-polarized Tfh subset was preferentially activated and its activation did not correlate with antibody responses. These data provide insights into the Tfh cell biology underlying suboptimal antibody responses to malaria in children and suggest that vaccine strategies that promote CXCR3- Tfh cell responses may improve malaria vaccine efficacy. © 2015 The Authors.
Zander R.A.,The University of Oklahoma Health Sciences Center |
Obeng-Adjei N.,National Institute of Allergy and Infectious Diseases |
Guthmiller J.J.,The University of Oklahoma Health Sciences Center |
Kulu D.I.,The University of Oklahoma Health Sciences Center |
And 5 more authors.
Cell Host and Microbe | Year: 2015
The differentiation and protective capacity of Plasmodium-specific T cells are regulated by both positive and negative signals during malaria, but the molecular and cellular details remain poorly defined. Here we show that malaria patients and Plasmodium-infected rodents exhibit atypical expression of the co-stimulatory receptor OX40 on CD4 T cells and that therapeutic enhancement of OX40 signaling enhances helper CD4 T cell activity, humoral immunity, and parasite clearance in rodents. However, these beneficial effects of OX40 signaling are abrogated following coordinate blockade of PD-1 co-inhibitory pathways, which are also upregulated during malaria and associated with elevated parasitemia. Co-administration of biologics blocking PD-1 and promoting OX40 signaling induces excessive interferon-gamma that directly limits helper T cell-mediated support of humoral immunity and decreases parasite control. Our results show that targeting OX40 can enhance Plasmodium control and that crosstalk between co-inhibitory and co-stimulatory pathways in pathogen-specific CD4 T cells can impact pathogen clearance. © 2015 Elsevier Inc.