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Wushan, China

South China Agricultural University commonly referred to as SCAU, is a public university in Guangzhou, China.Founded in 1909. Main campus settles in Wushan, Guangzhou, People's Republic of China. It is a national comprehensive university with long history. The university has 24 colleges/department and more than 40,000 students, including international students from 33 countries. The main feature of the university is biology science. Wikipedia.

Meng H.-M.,Hunan University | Jin Z.,South China Agricultural University | Lv Y.,Hunan University | Yang C.,Hunan University | And 3 more authors.
Analytical Chemistry | Year: 2014

Glutathione (GSH) serves vital cellular biological functions, and its abnormal levels are associated with many diseases. To better understand its physiological and pathological functions, efficient methods for monitoring of GSH in living systems are desired. Although quite a few small molecule-based and nanomaterial-based one photon fluorescence probes have been reported for GSH, two-photon (TP) probes, especially nanoprobes with good membrane permeability, are more favorable for bioimaging applications, since TP fluorescence imaging can provide improved spatial localization and increased imaging depth. In this work, we for the first time reported a "turn-on" TP fluorescence nanoprobe for efficient detection of GSH in aqueous solutions and TP excited fluorescence imaging of GSH in living cells and tissues. The nanoprobe consists of two-photon mesoporous silica nanoparticles (TP-MSNs) with a large TP excitation action cross-section (Φδ) value of 103 GM and MnO2 nanosheets, which show intense and broad optical absorption and could act as efficient quenchers for TP fluorescence. In the sensing system, the negatively charged MnO2 nanosheets are adsorbed on the positively charged MSNs through electrostatic interaction, resulting in efficient quenching of their fluorescence, with very low background fluorescence observed. The addition of GSH could reduce MnO2 into Mn2+, lead to the decomposition of the MnO2 nanosheets, and thereby result in remarkable enhancement of both one photon and TP excited fluorescence of the nanosystem. The nanoprobe shows a highly sensitive response to GSH in aqueous solutions, with a detection limit of 200 nM achieved. It also exhibits a high selectivity toward GSH relative to other biomolecules and electrolytes, with good membrane permeability and excellent biocompatibility. The nanoprobe was successfully applied in monitoring the change of the intracellular GSH in living cells and tissues via TP fluorescence imaging, demonstrating its value of practical application in biological systems. (Figure Presented). © 2014 American Chemical Society. Source

Gan Y.,South China University of Technology | Wang M.,South China University of Technology | Shi Y.,South China Agricultural University
Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering | Year: 2014

The experimental studies were carried out on the combustion temperature and stability of small-scale diffusion flames using ethanol as fuel both for free jet flow and confined jet flow. Results show that there are four conditions for the jet flow flames in the quiescent air, namely the quenching flames, stable combustion flames, quasi-oscillatory flames, and oscillatory flames. As Reynolds numbers increase, the flame peak temperatures increase firstly and then will decrease. For the free jet flow, the flame peak temperatures reach 1300K, and the exhaust gas temperatures increase, then keep stable, and may reach the maximum value of 480K. When using the quartz glass tube with a certain small diameter, the wall temperatures increase quickly with the increasing of Reynolds numbers, and may reach the maximum of 370 K. The upper combustion limits of confined flow are all less than that of free flow, but the lower combustion limits are very close. As the inner diameters of the quartz glass tubes decrease, the upper combustion limits decrease sharply. In the present parameter ranges, thermal quenching is the main factor for flame quenching, and the main reason causing the transition from stable flames to oscillatory flames is the fuel incomplete combustion. © 2014 Chinese Society for Electrical Engineering. Source

Wen L.-F.,Sun Yat Sen University | Wen L.-F.,South China Agricultural University | He J.-G.,Sun Yat Sen University
British Journal of Nutrition | Year: 2012

The aim of the present study was to evaluate the feasibility of an antimicrobial peptide, cecropin A(1-11)-D(12-37)-Asn (CADN), as an alternative to antibiotic growth promoter (AGP) in poultry diets. A total of 1500 14-d-old indigenous male chickens (222 (sd 13)g) were randomly allocated to five groups with five replicate cages of sixty birds each, and fed ad libitum five grower diets and subsequently five finisher diets for 14d each. The diets were made up by supplementing their basal diets with a CADN liquid sample (CADNL) at 0, 2, 4, 6 and 8ml/kg, respectively. During the feeding period, a metabolic experiment was carried out to determine the apparent digestibility of diethyl ether extract, nitrogen retention and apparent metabolisable energy of the diet sample fed to each cage of chicks. At the end of the feeding experiment, one chick from each cage was killed for bacteriological, light microscopic and scanning electron microscopic examination of the intestinal villi. CADN had a negative linear, positive quadratic and negative linear effect on feed intake (F), weight gain (G) and feed:gain ratio (F:G), respectively, for the growers; it had a quadratic effect on F, G or F:G for the finishers; it increased nutrient utilisation for both growers and finishers; it decreased aerobic bacterial counts in both jejunal and caecal digesta in a dose-dependent manner; it enhanced intestinal villus heights in a dose-dependent manner and made the duodenum villi of the CADNL8 group at 42d appear as a netted leaf-like structure. CADN is therefore a possible alternative to AGP in broiler feeds. © 2012 The Authors. Source

Nie P.-Y.,Guangdong University of Finance and Economics | Yang Y.-C.,Guangdong University of foreign Studies | Chen Y.-H.,South China Agricultural University | Wang Z.-H.,Guangdong University of Finance and Economics
Applied Energy | Year: 2016

Establishing a game theory model, this paper captures the effects of output subsidy on energy efficiency under Cournot competition and Stackelberg competition. Three types of subsidies are considered in the model, namely without subsidy, unilateral subsidy and bilateral subsidy. The findings indicate that firms without subsidy are not willing to improve energy efficiency. Also, subsidy stimulates the subsidized firms' outputs while deters the outputs of other firms. Meanwhile, the equilibrium subsidy intensity depends on firms' position. Furthermore, the minimal subsidy budgets under different situations are presented. Especially, given the fixed subsidy budget, the output of the subsidized firm is the highest if this firm plays the leading position. In addition, certain subsidy can reduce the total emission, while overdue subsidy cannot reach the environmental object. © 2016 Elsevier Ltd. Source

Sun J.,Beijing Technology and Business University | Zhu J.,Beijing Technology and Business University | Liu X.,South China Agricultural University | Du H.,Beijing Technology and Business University
Materials Research Bulletin | Year: 2013

Er3+/Ho3+/Yb3+/Tm3+ co-doped YVO4 phosphors were synthesized by the conventional solid-state reaction. Under 980 nm laser diode excitation, intense red, green and blue up-conversion emissions were observed for the Yb3+/Er3+, Yb3+/Ho3+ and Yb3+/Tm3+ couples in the YVO4 host, respectively, which were due to the successive energy transfer from Yb3+ to Er3+, Ho3+ or Tm 3+. Bright white luminescence upon 980 nm near-infrared excitation can be observed for the sample at the optimum chemical composition of YVO 4:10%Yb3+/1%Tm3+/0.3%Ho3+/0. 2%Er3+. Under different excitation pump powers, the obtained optimal color coordinate (0.323, 0.325) is very close to the standard white light (0.333, 0.333) coordinate. © 2013 Elsevier Ltd. Source

Zhu G.,South China Agricultural University | Liu Y.,Hong Kong Baptist University | Liu Y.,Shandong Agricultural University | Ye N.,Hong Kong Baptist University | And 2 more authors.
Physiologia Plantarum | Year: 2011

Earlier studies showed that sugars as signaling molecules play pivotal roles in the regulation of seed germination. ABA biosynthesis upregulation is suggested as one of the possible mechanisms mediating the glucose-induced delay in seed germination. In this study, the role of ABA catabolism in glucose-induced inhibition was investigated. Using Arabidopsis thaliana seeds, the results show that the repression of ABA catabolism by diniconazole aggravated the glucose-induced delay in seed germination. The transcript and protein profiles of CYP707A2, a key gene encoding ABA 8′-hydroxylase in ABA catabolism in Arabidopsis, were significantly decreased by exogenous glucose treatment. Transgenic experiments confirmed that the over-expression of the CYP707A2 gene alleviated the glucose-induced inhibition effect, whereas the cyp707a2 mutant seeds displayed a hypersensitivity to glucose during imbibition. Exogenous glucose also arrested the early seedling development of Arabidopsis. The CYP707A2 over-expression seedlings exhibited lower ABA levels and seemed less sensitive to exogenous glucose compared with wild type seedlings. In summary, the glucose-induced delay in seed germination and seedling development is directly related to the suppression of ABA catabolism through the repression of the CYP707A2 expression. © 2011 Physiologia Plantarum. Source

Hamalainen M.,Netherlands Center for Biodiversity Naturalis | Yu X.,Nankai University | Zhang H.,South China Agricultural University
Zootaxa | Year: 2011

Matrona oreades Hämäläinen, Yu & Zhang, spec. nov. (holotype ♂ China, Gansu, Wenxian, Bikou, alt. 950m, 9/13 vii 2005) and Matrona corephaea Hämäläinen, Yu & Zhang, spec. nov. (holotype ♂ China, Zhejiang, West Tianmushan, alt. 700m, 8 viii 2007) are described and illustrated for both sexes. These two species differ markedly from the members of the Matrona basilaris species group by their sparser venation and absence of bluish-white reticulation at the wing base. Copyright © 2011 Magnolia Press. Source

Liu M.,Nanjing Normal University | Liu M.,South China Normal University | Liu M.,South China Agricultural University | Liu B.,South China Normal University
Match | Year: 2013

In this paper, we report some recent results, mainly focusing on the ordering results, of some typical variable Wiener indices, Wiener polarity index or hyper-Wiener index in some given classes of graphs. Source

Cui J.,Guangdong Institute of Eco environmental and Soil Sciences | Liu Y.,South China Agricultural University
RSC Advances | Year: 2015

In this work, we present a simple approach for the deposition of silver nanowires onto graphene oxide sheets (GO-Ag NWs). Silver nanowires (Ag NWs) were evenly distributed and tightly adherent to the surface of the graphene oxide (GO) sheets. The results from this study showed that silver ions were released from the GO sheets in a constant and slow manner. Importantly, the results showed that the antibacterial activity of the GO-Ag NWs was much more potent than that of the silver nanowires. Changes in the cellular morphology, the level of reactive oxygen species (ROS) and the content of DNA and RNA were also investigated. It was demonstrated that the cell membrane integrity was damaged, and DNA, RNA and proteins leaked out due to oxidative damage of the bacteria through the release of ROS, brought about by the silver ions. On the basis of the present investigation, a plausible antibacterial mechanism of the GO-Ag NWs composites was proposed. Lastly, the results showed that the samples which decreased bacterial growth the most did not inhibit human skin keratinocyte cell growth compared to the Ag NWs. In summary, the results from this study indicated that the GO-Ag NWs provided unprecedented antibacterial properties while maintaining the cell proliferation capacity necessary for enhancing the wide use of silver in medical applications. © 2015 The Royal Society of Chemistry. Source

Wang C.,Rutgers University | Wen X.,South China Agricultural University
Insects | Year: 2011

The bed bug resurgence in North America, Europe, and Australia has elicited interest in investigating the causes of the widespread and increasing infestations and in developing more effective control strategies. In order to extend global perspectives on bed bug management, we reviewed bed bug literature in China by searching five Chinese language electronic databases. We conducted telephone interviews of staff from 77 Health and Epidemic Prevention Stations in six Chinese cities in November 2010. We also conducted telephone interviews of 68 pest control firms in two cities during March 2011. Two species of bed bugs (Cimex lectularius L. and Cimex hemipterus (F.)) are known to occur in China. These were common urban pests before the early1980s. Nationwide Four-Pest Elimination campaigns (bed bugs being one of the targeted pests) were implemented in China from 1960 to the early 1980s. These campaigns succeeded in the elimination of bed bug infestations in most communities. Commonly used bed bug control methods included applications of hot water, sealing of bed bug harborages, physical removal, and applications of residual insecticides (mainly organophosphate sprays or dusts). Although international and domestic travel has increased rapidly in China over the past decade (2000-2010), there have only been sporadic new infestations reported in recent years. During 1999-2009, all documented bed bug infestations were found in group living facilities (military dormitories, worker dormitories, and prisons), hotels, or trains. One city (Shenzhen city near Hong Kong) experienced significantly higher number of bed bug infestations. This city is characterized by a high concentration of migratory factory workers. Current bed bug control practices include educating residents, washing, reducing clutter, putting items under the hot sun in summer, and applying insecticides (pyrethroids or organophosphates). There have not been any studies or reports on bed bug insecticide resistance. Difficulties of control were noted in our surveys of dormitories in which crowded living, seasonal worker migration, and financial constraints contributed to control failures. This study supports the following conclusions: (1) the bed bug infestation in China dramatically decreased following the campaigns from 1960 to the early 1980s; (2) In our survey of Health and Epidemics Prevention Stations, no bed bug cases were reported in Beijing and Shanghai for the past 12 months, but complaints were reported in Guangzhou, Lanzhou, Urumqi, and Shenzhen; (3) Current bed bug infestations primarily are reported in crowded living environments or transient environments such as worker dormitories and military dormitories. These findings suggest that community-wide bed bug monitoring and control campaigns are necessary for effective control of bed bug infestations as a societal response. © 2011 by the authors; licensee MDPI, Basel, Switzerland. Source

Ma L.,University of Texas at Arlington | Jiang K.,University of Colorado at Colorado Springs | Liu X.-T.,University of Texas at Arlington | Liu X.-T.,South China Agricultural University | Chen W.,University of Texas at Arlington
Journal of Applied Physics | Year: 2014

We prepared manganese and europium co-doped zinc sulfide (ZnS:Mn,Eu) phosphors and used them for radiation detection. In addition to the red fluorescence at 583 nm due to the d-d transition of Mn ions, an intense violet emission at 420 nm is newly observed in ZnS:Mn,Eu phosphors. The emission is related to Eu2+ doping but only appears at certain Eu2+ concentrations. It is found that the intensity of the 420 nm violet fluorescence is X-ray does-dependent, while the red fluorescence of 583 nm is not. The ratio of fluorescence intensities at 420 nm and 583 nm has been monitored as a function of X-ray doses that exposed upon the ZnS:Mn,Eu phosphors. Empirical formulas are provided to estimate the doses of applied X-ray irradiation. Finally, possible mechanisms of X-ray irradiation induced fluorescence quenching are discussed. The intense 420 nm emission not only provides a violet light for solid state lighting but also offers a very sensitive method for radiation detection. © 2014 AIP Publishing LLC. Source

Xiong W.,Sun Yat Sen University | Xiong W.,South China Agricultural University | Zhong F.,Sun Yat Sen University | Yuan W.,Sun Yat Sen University | Fan S.,Sun Yat Sen University
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2010

We have investigated the critical behavior of a three-dimensional random-bond Ising model for a series of the disorder strength by a finite-time scaling combining with Monte Carlo renormalization-group method in the presence of a linearly varying temperature. The method enables us to estimate a lot of critical exponents of both static and dynamic nature independently as well as the critical temperatures. The static exponents obtained agree well with most existing results, verify both the hyperscaling and the Rushbrooke scaling laws and their combined scaling law, which in turn validate their asymptotic nature, and corroborate the universality of the relevant random fixed point with respect to the forms of disorder. The dynamic critical exponent z is estimated to 2.114(51), which is compatible with those obtained from experiments and renormalization-group analyses. The exponents at low and high disorder strengths do not satisfy all scaling laws and are argued to be crossover exponents that reflect crossover from the random fixed point to the pure and the percolation fixed point. They also indicate that the exponents that were previously suggested to be a distinct universality class for strong disorder strength in the literature may be just crossover. Our results demonstrate the effectiveness of the finite-time scaling method. © 2010 The American Physical Society. Source

Zhang N.,South China Agricultural University
Neural Computing and Applications | Year: 2015

We extend LS-SVM to ordinal regression, which has wide applications in many domains such as social science and information retrieval where human-generated data play an important role. Most current methods based on SVM for ordinal regression suffer from the problem of ignoring the distribution information reflected by the samples clustered around the centers of each class. This problem would degrade the performance of SVM-based methods since the classifiers only depend on the scattered samples on the border which induce large margin. Our method takes the samples clustered around class centers into account and has a competitive computational complexity. Moreover, our method would easily produce the optimal cut-points according to the prior class probabilities and hence may obtain more reasonable results when the prior class probabilities are not the same. Experiments on simulated datasets and benchmark datasets, especially on the real ordinal datasets, demonstrate the effectiveness of our method. © 2015 The Natural Computing Applications Forum Source

Liu Z.,South China Agricultural University
Journal of Information and Computational Science | Year: 2015

The microblogging has become the important platform for expressing emotion, therefore it is critical for charitable organizations to monitor the public opinion in microblogging. This paper studied the evolution of the public emotions during the charity events. Firstly, we constructed a hierarchical emotion model for events and an emotion monitoring surveillance model. Secondly, we used three machine learning algorithms and three kinds of feature selection methods to study the emotion classification for Chinese microblogging about the events. The experimental results show the performance of SVM and IG feature selection is best, and the accuracy of the classification is fit for need, then the paper discussed a charity event and analyses the evolution of emotions. ©, 2015, Binary Information Press. All right reserved. Source

Xu K.,Nanjing University of Aeronautics and Astronautics | Liu M.,Nanjing Normal University | Liu M.,South China Agricultural University | Ch. Das K.,Sungkyunkwan University | And 3 more authors.
Match | Year: 2014

This survey outlines results on graphs extremal with respect to distance-based indices, with emphasis on the Wiener index, hyper-Wiener index, harary index, wiener polarity index, reciprocal complementary Wiener index, and terminal Wiener index. Source

Li T.,Shandong University | He S.,Shandong University | Zhao H.,Shandong University | Zhao G.,Shandong University | And 2 more authors.
Trends in Parasitology | Year: 2010

Tremendous progress has been made in the control and prevention of human parasitic diseases in mainland China in the past 30 years because of China's Reform and Opening to the Outside Policies initiated in 1978. However, parasitic diseases remain a major human health problem, with significant morbidity and mortality as well as adverse socioeconomic consequences. Although soil-transmitted parasitic diseases are in the process of being gradually controlled, food-borne parasitic diseases and emerging parasitic diseases are becoming the focus of new campaigns for control and prevention. This article reviews major trends in human parasitic diseases in mainland China, with perspectives for control. © 2010 Elsevier Ltd. Source

Mirab-Balou M.,Zhejiang University | Tong X.-L.,South China Agricultural University | Feng J.-N.,Northwest University, China | Chen X.-X.,Zhejiang University
Check List | Year: 2011

A new checklist of Thysanoptera from China (including Taiwan) is provided. In total 566 species in 155 genera are listed, of which there are 313 species in the suborder Terebrantia, comprising 290 species in 74 genera in family Thripidae, 18 species in three genera in Aeolothripidae, two species in one genus in Melanthripidae and three species in one genus in Merothripidae. In the suborder Tubulifera 253 species in 76 genera are listed in the single family Phlaeothripidae. Two species, Aeolothrips collaris and Odontothrips meliloti, are newly recorded for the fauna of China. © 2011 Check List and Authors. Source

Morris K.,University of Warwick | Linkies A.,Albert Ludwigs University of Freiburg | Muller K.,Albert Ludwigs University of Freiburg | Oracz K.,Albert Ludwigs University of Freiburg | And 4 more authors.
Plant Physiology | Year: 2011

The completion of germination in Lepidium sativum and other endospermic seeds (e.g. Arabidopsis [Arabidopsis thaliana]) is regulated by two opposing forces, the growth potential of the radicle (RAD) and the resistance to this growth from the micropylar endosperm cap (CAP) surrounding it. We show by puncture force measurement that the CAP progressively weakens during germination, and we have conducted a time-course transcript analysis of RAD and CAP tissues throughout this process. We have also used specific inhibitors to investigate the importance of transcription, translation, and posttranslation levels of regulation of endosperm weakening in isolated CAPs. Although the impact of inhibiting translation is greater, both transcription and translation are required for the completion of endosperm weakening in the whole seed population. The majority of genes expressed during this process occur in both tissues, but where they are uniquely expressed, or significantly differentially expressed between tissues, this relates to the functions of the RAD as growing tissue and the CAP as a regulator of germination through weakening. More detailed analysis showed that putative orthologs of cell wall-remodeling genes are expressed in a complex manner during CAP weakening, suggesting distinct roles in the RAD and CAP. Expression patterns are also consistent with the CAP being a receptor for environmental signals influencing germination. Inhibitors of the aspartic, serine, and cysteine proteases reduced the number of isolated CAPs in which weakening developed, and inhibition of the 26S proteasome resulted in its complete cessation. This indicates that targeted protein degradation is a major control point for endosperm weakening. © 2011 American Society of Plant Biologists. Source

Xu S.,South China Agricultural University
Sensors (Basel, Switzerland) | Year: 2014

Principal Component Analysis (PCA) is one of the main methods used for electronic nose pattern recognition. However, poor classification performance is common in classification and recognition when using regular PCA. This paper aims to improve the classification performance of regular PCA based on the existing Wilks Λ-statistic (i.e., combined PCA with the Wilks distribution). The improved algorithms, which combine regular PCA with the Wilks Λ-statistic, were developed after analysing the functionality and defects of PCA. Verification tests were conducted using a PEN3 electronic nose. The collected samples consisted of the volatiles of six varieties of rough rice (Zhongxiang1, Xiangwan13, Yaopingxiang, WufengyouT025, Pin 36, and Youyou122), grown in same area and season. The first two principal components used as analysis vectors cannot perform the rough rice varieties classification task based on a regular PCA. Using the improved algorithms, which combine the regular PCA with the Wilks Λ-statistic, many different principal components were selected as analysis vectors. The set of data points of the Mahalanobis distance between each of the varieties of rough rice was selected to estimate the performance of the classification. The result illustrates that the rough rice varieties classification task is achieved well using the improved algorithm. A Probabilistic Neural Networks (PNN) was also established to test the effectiveness of the improved algorithms. The first two principal components (namely PC1 and PC2) and the first and fifth principal component (namely PC1 and PC5) were selected as the inputs of PNN for the classification of the six rough rice varieties. The results indicate that the classification accuracy based on the improved algorithm was improved by 6.67% compared to the results of the regular method. These results prove the effectiveness of using the Wilks Λ-statistic to improve the classification accuracy of the regular PCA approach. The results also indicate that the electronic nose provides a non-destructive and rapid classification method for rough rice. Source

Yu M.,South China Agricultural University
Proceeding of 2012 International Conference on Information Management, Innovation Management and Industrial Engineering, ICIII 2012 | Year: 2012

The paper empirically analyzes the impact of technology spillovers of trade in intermediates on wage inequality in China using data for a panel of 28 manufacturing industries over the 1997-2009 period. The results show that, the foreign R&D capital embodied in intermediates could be more complementary with skilled labour than unskilled labour, knowledge learning and imitation are biased in favor of skilled labor, so that the foreign technology spillover of trade in intermediates is associated with an increase in skill demand and a trend of rising in the skilled-unskilled wage inequality in Chinese manufacturing. ©2012 IEEE. Source

Wang H.,Cornell University | Wang H.,South China Agricultural University | Cheng L.,Cornell University
HortScience | Year: 2011

Apple maturity is often assessed by starch hydrolysis index, skin color, soluble solids, flesh firmness, and the rate of ethylene evolution. In red-fruited apple cultivars, the intensity and extent of coloration is an important consideration in determining the time of fruit harvest. Negative relationships have been found between tree nitrogen (N) status and fruit skin pigmentation, but how N affects flesh starch breakdown has not been examined in detail. The objective of this study was to determine howN supply affects flesh starch breakdown relative to skin color development. Seven-year-old 'Gala'/M.26 trees were provided with four levels of N (8.8, 26.4, 52.7, and 105.4 g N per tree) in a modified Hoagland's solution. The effects of N supply on yield, fruit quality, and fruit maturation were evaluated. At harvest, fruit in the lowest N treatment was significantly smaller and had lower soluble solids but higher starch concentration, better color, and higher firmness than those grown at higher N supplies. Increasing N supply decreased both anthocyanin synthesis and chlorophyll degradation in fruit skin. Flesh starch concentration was higher at higher N supply at 38 days before harvest but was lower at higher N supply at harvest. Starch degradation was completed earlier during cold storage with increasing N supply. These results indicate that increasing N supply delays skin red color development but accelerates flesh starch degradation in 'Gala' apples. These differential effects of N supply should be taken into account when assessing fruit maturity for optimizing harvest time. Source

Qiu H.,South China Agricultural University | Du Y.,South China Normal University | Yao Z.,Sun Yat Sen University
Nonlinear Analysis: Real World Applications | Year: 2011

In this paper, we consider the two-dimensional Newton-Boussinesq equations with the incompressibility condition. We obtain a regularity criterion for the Newton-Boussinesq equations by virtue of the commutator estimate. © 2011 Elsevier Ltd. All rights reserved. Source

Sealey W.M.,University of Idaho | Hardy R.W.,University of Idaho | Barrows F.T.,U.S. Department of Agriculture | Pan Q.,South China Agricultural University | Stone D.A.J.,South Australian Research And Development Institute
Journal of the World Aquaculture Society | Year: 2011

The ability of poultry products to replace fish meal in diets for rainbow trout, Oncorhynchus mykiss, depends on their nutrient composition, cost, and consistency. The aim of this study was to assess the ability of three commercially available poultry products (chicken concentrate, CC, poultry by-product blend, PBB; or chicken and egg concentrate, CE) to maintain growth and disease resistance when substituted for fish meal in a rainbow trout starter diet. A control diet was formulated to contain 48% crude protein and 18% crude lipid; 100% of the fish meal in test diets was replaced with CC, PBB, or CE. At stocking, fry were counted into groups (50 fish/tank) with six replicate tanks for each diet and fed their respective diets four times daily for 8 wk. All the poultry-based diets supported growth (over 1600% increase over initial weight), nutrient retention, and feed conversion ratios of rainbow trout fry equal to or greater than those observed for fry fed with the fish meal-based diet. No effect of diet on survival was observed following subcutaneous injection challenge with Flavobacterium psychrophilum. These data suggest that the examined products can be used in place of fish meal for rainbow trout fry without lowering growth and disease resistance. © by the World Aquaculture Society 2011. Source

Shen J.,Qingdao Agricultural University | Pinyopusarerk K.,CSIRO | Bush D.,CSIRO | Chen X.,South China Agricultural University
Biomass and Bioenergy | Year: 2012

Amplified fragment length polymorphism (AFLP) fluorescence primers were used to characterize the genetic variation among 63 populations of Jatropha curcas from 10 countries in Asia, Africa and Mexico grown in provenance trials in China and Vietnam. Four primer combinations were used to generate a total of 89 bands of which 87 were polymorphic. Total genetic diversity (Ht) was low (0.15). AMOVA partitioned 31% of variability among populations and 69% within populations. Gene flow (Nm) was found to be low, 0.44, suggesting limited gene exchange among populations. Polymorphic loci (Np=16), the percentage of polymorphic loci (Pp=18%), Nei's diversity index (H=0.07) and Shannon's information index (I=0.10) all indicated low genetic diversity among populations. The populations from Mexico were exceptional as they all displayed high genetic diversity. The UPGMA-based dendrogram, with corroborative indications from Principal Coordinates Analysis, divided the populations into 4 major clusters. Subpopulations from a wide geographic range within India formed a major cluster suggesting a common origin for these subpopulations; the same was indicated for many of the Chinese subpopulations. Material from a wide range of countries in Southeast Asia and accessions from Africa formed another cluster. The Mexican populations formed a fourth, separate group, relatively distant from the other three clusters, indicating that the Asian material probably does not originate from Mexico. Despite generally low genetic diversity of cultivated Jatropha curcas in Asia, this study identified 6 Asian populations with genetic diversity considerably higher than overall population mean. Though the impact of inbreeding on jatropha fitness is not yet well-understood, it is probable that broadening the genetic base will benefit breeding programs in Asia, guarding against inbreeding depression and providing a range of material with the genetic diversity to adapt to a wide range of planting sites. Drawing from the more-diverse populations identified in Asia as well as from wild material originating in Mexico and other parts of the natural range would be a sound strategy when applied in concert with further research on the species' breeding system, quantitative trait variation and environmental plasticity. © 2011 Elsevier Ltd. Source

Li T.,South China University of Technology | Li T.,South China Agricultural University | Xiao N.,South China University of Technology
Journal of Convergence Information Technology | Year: 2012

In this paper we introduce a new feature dimensionality reduction method for decision tree classification. We combine the neural network with decision tree, first, the paper analyzes the problem about dimensionality reduction, sorts the feature value in importance order in the first place, second, we take advantage of the black box classification characteristic of neural network which does not need a priori knowledge, and its high-efficiency in classification, prune high dimensional data one by one, select several most effective basic features for data classification, we get the effect of dimensionality reduction by using this method. Source

Xiong P.,South China Agricultural University
Nan fang yi ke da xue xue bao = Journal of Southern Medical University | Year: 2010

To study the protective mechanisms of the astragaloside against ischemia-reperfusion lung injury in rats. Ischemia-reperfusion lung injury was induced in SD rats. Astragalus armour glucoside was dissolved in 1% of sodium carboxymethyl cellulose at different concentrations (8, 6, and 3 mg/ml) was intragastrically administered in the rats at the dose of 1 ml/100 g. Cellular and subcellular structural changes in the lung tissue were observed at the end of the experiment using optical and transmission electron microscope, with the wet/dry ratio of the lung tissue and myeloperoxidase (MPO) activity measured. The wet/dry ratio and myeloperoxidase activity in the lung tissue were significantly higher in the model group than in the sham-operated group (P<0.05), and were significantly lowered by the treatment with astragalus armour glucoside at different doses (P<0.01 or 0.05), and the effect was especially obvious in rats receiving a moderate dose. Pulmonary capillary expansion, erythrocyte leakage and exudate in the alveolar space with obvious pathological changes in the type I and II epithelial cells were observed in model group. Pulmonary capillary expansion was reduced in rats treated with high, medium and low dose of Astragalus armour glucoside, and the medium dose group showed the most obvious effect, in which no edema fluid in the alveolar space or erythrocyte leakage was found with also reduced type II lung epithelial cell degranulation. Astragaloside has obvious antioxidant effect in rats with ischemia-reperfusion lung injury, and a medium dose produces the best effect. Source

Guglielmino A.,University of Tuscia | Xu Z.,South China Agricultural University | Bckle C.,Neckarhalde 48 | Dong W.,Anhui Academy of Agricultural Sciences
Florida Entomologist | Year: 2012

A new species of leafhopper, Arboridia sinensis sp. nov., belonging to the subgenus Arboridia Zachvatkin, 1946 s. str. and closely related to Arboridia (Arboridia) gaurii Thapa, 1989, A. cerna Dworakowska, 1977, and A. soror Dworakowska, 1977, is described from Yunnan, China. It differs from A. gaurii in the body coloration and aedeagus shape, and from A. cerna and A. soror also in the shape of its pygofer process. In Yunnan, China the new species lives on Zanthoxylum bungeanum Maximowicz (Rutaceae). Source

Wang C.,Sun Yat Sen University | Wang C.,South China Agricultural University | Ni J.,Sun Yat Sen University | Huang J.,Sun Yat Sen University
IEEE Transactions on Information Forensics and Security | Year: 2012

Achieving robustness, imperceptibility and high capacity simultaneously is of great importance in digital watermarking. This paper presents a new informed image watermarking scheme with high robustness and simplified complexity at an information rate of 1/64 bit/pixel. Firstly, a Taylor series approximated locally optimum test (TLOT) detector based on the hidden Markov model (HMM) in the wavelet domain is developed to tackle the problem of unavailability of exact embedding strength in the receiver due to informed embedding. Then based on the TLOT detector and the concept of dirty-paper code design, new HMM-based spherical codes are constructed to provide an effective tradeoff between robustness and distortion. The process of informed embedding is formulated as an optimization problem under the robustness and distortion constraints and the genetic algorithm (GA) is then employed to solve this problem. Moreover, the perceptual distance in the wavelet domain is also developed and incorporated into the GA-based optimization. Simulation results demonstrate that the proposed informed watermarking algorithm has high robustness against common attacks in signal processing and shows a comparable performance to the state-of-the-art scheme with a greatly reduced arithmetic complexity. © 2012 IEEE. Source

Zhou X.,South China University of Technology | Peng F.,South China University of Technology | Wang H.,South China University of Technology | Yu H.,South China University of Technology | Fang Y.,South China Agricultural University
Chemical Communications | Year: 2011

Novel carbon nitride polymer sensitized TiO 2 nanotube arrays with high photocatalytic activity and photoelectrochemical response under visible light irradiation are prepared by electrodeposition. © 2011 The Royal Society of Chemistry. Source

Hussain A.,South China Agricultural University | Ahmed S.,University of Agriculture at Faisalabad | Shahid M.,University of Agriculture at Faisalabad
Neotropical Entomology | Year: 2011

The efficacy of the Metarhizium anisopliae strain ARSEF 6911 was determined in the laboratory and field against two sugarcane pests, Microtermes obesi Holmgren and Odontotermes obesus Rambur (Termitidae: Isoptera). The susceptibility of both termite species to different conidial suspensions (1×1010, 1×108, 1×106 and 1×104 conidia/ml) was determined in laboratory. All conidial suspensions were able to induce mortality. Termite mortality caused by the fungal suspensions was dose dependent. There were no significant differences in the LT50 values between species. Field evaluation of M. anisopliae alone or in combination with diesel oil and thiamethoxam was carried out in two growing seasons (autumn 2005 and spring 2006) at two sites located in Punjab, Pakistan. Dipping the sugarcane setts in these suspensions was tried to determine their effects on germination and percentage of bud damage to sugarcane setts. All treatments significantly reduced termite infestation compared to the untreated control. The combined treatment of M. anisopliae and diesel oil significantly reduced insect damage by attaining higher germination>55% and lower bud damage<5.50% at both sites in both seasons. The results suggest that the application of M. anisopliae and diesel oil in combination might be a useful treatment option for the management of termites in sugarcane. © 2011 Sociedade Entomológica do Brasil. Source

Li R.,Sun Yat Sen University | Dan X.,South China Agricultural University | Li A.,Sun Yat Sen University
Fish and Shellfish Immunology | Year: 2013

A novel antimicrobial and antiparasitic protein (APP/SR-LAAO) isolated from serum of the rabbitfish (Siganus oramin) was confirmed to be lethal to Cryptocaryon irritans, an important marine parasitic ciliate that causes marine white spot disease in a variety of wild and cultured fish. In this study, a recombinant SR-LAAO (rSR-LAAO) was expressed on a large scale in Escherichia coli Rosetta-gami™(DE3)pLysS cells. rSR-LAAO was expressed as an inactive form in the inclusion bodies. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that after purification, refolding and ultrafiltration, rSR-LAAO had a significantly cytotoxic effect on C. irritans theronts. Using light microscopy, scanning electron microscopy and fluorescence microscopy, we found that theronts rapidly became weakly motile, cilia became detached, cells became rounded, membranes eventually lysed in different cell positions and cytoplasmic contents leaked out of the cell. These results suggested the recombinant SR-LAAO was significantly lethal to C.irritans and the death process of the parasite incubated with rSR-LAAO was remarkably similar compared to the SR-LAAO group as reported earlier. © 2013 Elsevier Ltd. Source

Tan X.,City University of Hong Kong | Huang Q.,South China Agricultural University | Wong D.S.,City University of Hong Kong
Theoretical Computer Science | Year: 2014

Since the introduction of concurrent signature, improved results have been obtained on constructing schemes with enhanced ambiguity, refined security models and better efficiency, while extending concurrent signature to multiple users, that is, allowing n parties (where n ≥ 2) to perform fair exchange of signatures concurrently, is still one of the most challenging problems that remain unsolved. In the literature, there is a three-party concurrent signature scheme which achieves a weaker form of ambiguity, that an ambiguous signature can either be generated by the real signer or jointly by the other two parties, but not by any single party of the rest. There are also two other multi-party concurrent signature schemes. However, both of them have been found insecure, that they could not achieve unforgeability, ambiguity, and fairness simultaneously. Furthermore, there is no formal security model available for Multi-party Concurrent Signature (MCS). In this paper, we propose an efficient MCS construction and show its security in the random oracle model under our newly proposed security model for MCS. The scheme is also comparable in efficiency to the best existing two-party concurrent signature schemes. © 2014 Elsevier B.V. Source

Zou Y.-N.,Yangtze University | Wu Q.-S.,Yangtze University | Wu Q.-S.,South China Agricultural University
Notulae Botanicae Horti Agrobotanici Cluj-Napoca | Year: 2011

Citrus plants are sensitive to salinity, and thus employing new approaches to alleviate salt damage are necessary. The present study evaluated the effect of two arbuscular mycorrhizal fungi (AMF), Glomus mosseae and G. versiforme, on leaf osmotic adjustment of trifoliate orange (Poncirus trifoliata) seedings exposed to 100 mM NaCl. Salinity significantly inhibited mycorrhizal colonization, plant biomass and leaf relative water content, whereas the reduce of plant biomass was notably alleviated by the mycorrhizal colonization. Mycorrhizal seedlings exhibited significantly lower Na + and Ca 2+ concentrations, whilst also recorded higher K+ concentration and K +/Na +, Ca 2+/Na + and Mg 2+/Na + ratios at both salinity levels. Under salinity stress, mycorrhizal symbiosis markedly decreased sucrose concentrations of leaves and also increased glucose, fructose and proline concentrations of leaves. The results suggest that arbuscular mycorrhizas improved leaf osmotic adjustment responses of the seedlings to salt stress, thus enhancing salt tolerance of mycorrhizal plants. Source

Chen G.,Dongguan University of Technology | Luo Z.,South China Agricultural University | Wu J.,University of Toronto | Wu M.,Dongguan University of Technology
Journal of the Physical Society of Japan | Year: 2013

We study the possibility of switching the types of symmetry breaking bifurcation (SBB) in the cylinder shell waveguide with helical double-well potential along propagation direction. This model is described by the onedimensional nonlinear Schrödinger (NLS) equation. The symmetry- and antisymmetry-breakings can be caused by increasing the applied voltage onto the waveguide in the self-focusing and -defocusing cases, respectively. In the selffocusing case, the type of SBB can be switched from supercritical to subcritical. While in the self-defocusing case, the type of SBB can not be switched because only one type of SBB is found. © 2013 The Physical Society of Japan. Source

Ou J.,South China Agricultural University | Sun Z.,Shanghai Ocean University
Journal of Functional Foods | Year: 2014

Feruloylated oligosaccharides consist of a large group of compounds that are mainly produced from the hydrolysis of feruloylated polysaccharides. Some are commercially available in the market. In the bound form, ferulic acid is usually esterified at position C-2 or C-5 to l-arabinofuranosyl residues, at position C-6 to β-D-galactopyranosyl residues, and at position C-4 to d-xylopyranosyl residues. This review summarises current knowledge on feruloylated oligosaccharides, including their structures, physiological functions, preparation methods, metabolism and absorption in the colon. Future research trends are also discussed. © 2013 Elsevier Ltd. Source

Liu J.-Q.,Sichuan University | Duan Y.-W.,CAS Kunming Institute of Botany | Hao G.,South China Agricultural University | Ge X.-J.,CAS South China Botanical Garden | Sun H.,CAS Kunming Institute of Botany
Journal of Systematics and Evolution | Year: 2014

As the highest and largest plateau in the world, the Qinghai-Tibet Plateau, with its numerous endemic species, is one of the important alpine biodiversity hotspots. Only recently have the evolutionary histories and underlying adaptations of these alpine plants become clear, through research mostly based on testable experiments and analyses. In this issue, we collected a total of 13 papers related to such aims. In addition, we selected a few published papers to highlight the major findings in the recent past. We also outlined the outlook and direction of future research. © 2014 Institute of Botany, Chinese Academy of Sciences. Source

Jialin L.,Ningbo University | Hangbin Z.,South China Agricultural University | Xiaoping Y.,Ningbo University
African Journal of Agricultural Research | Year: 2011

The temporal and spatial variation of vegetation index is a hot issue in global change research currently. Spartina alterniflora salt marsh in Jiangsu coastal areas is taken as an example in this study, MODIS data is used to research NDVI/EVI seasonal variation laws of coastal zonal vegetation. The results show that the major phenological periods of S. alterniflora, such as turning green (seedling emergence), heading and seed maturity, could be well reflected with VI curves. This study provides basic data for monitoring expansion trend of S. alterniflora salt marsh, strengthening management, drawing on advantages and avoiding disadvantages, as well as supplying references for monitoring of other zonal vegetation in coastal areas. © 2011 Academic Journals. Source

Chen L.,South China Agricultural University
China Agricultural Economic Review | Year: 2011

Purpose - The paper aims to examine the relationship between changes and volatility of China's Renminbi (RMB) exchange rates and its agricultural export. Design/methodology/approach - A GARCH(1, 1) model is specified to measure the exchange rate volatility and autoregressive distributed lag regression with structural break dummy variables is estimated based on the results of unit root test with structural break. Findings - The export supply model reveals that the net trade effect of RMB exchange rate movements relies on the comparison of exchange rate level change (appreciation or depreciation) effect and exchange rate risk effect. The empirical examination results, taking China's agricultural exports to Japan as a case, show RMB depreciation against yen will promote export growth while appreciation hinder export, and exchange rate volatility positively stimulates agricultural exports to Japan. However, the effect of exchange rate volatility on the export is much smaller than that of exchange rate level, which leads to a negative net effect to the export. Originality/value - The constructed model and applied methodology contribute to a better understanding of the relationship between changes and volatility of China's RMB exchange rates and its agricultural export. Copyright © 2011 Emerald Group Publishing Limited. All rights reserved. Source

Zhang J.,South China Agricultural University
Grassland Science | Year: 2011

The effects of chopping length, cellulase addition and their interaction on the silage fermentation quality of fresh guineagrass (Panicum maximum Jacq. cv. Natsukaze) were investigated. The grass was ensiled in laboratory silos after chopping into 1, 3 or 6cm, with or without Acremonium cellulase (AC). After ensiling for 100days, gas production and chemical composition of silages were measured. The chopping length of 3cm was beneficial to lactic acid fermentation. The AC addition significantly decreased acetic acid contents and increased total acids (P<0.01). Chopping and AC addition had a significant interaction on all fermentation parameters except NH3-N content (P<0.01). © 2011 The Authors. Grassland Science © 2011 Japanese Society of Grassland Science. Source

Yan H.-F.,CAS South China Botanical Garden | Hao G.,South China Agricultural University | Hu C.-M.,CAS South China Botanical Garden | Ge X.-J.,CAS South China Botanical Garden
Journal of Systematics and Evolution | Year: 2011

DNA barcoding is a method of identifying species by analyzing one or a few short standardized DNA sequences. There are particular challenges in barcoding plants, especially for distinguishing closely related species. Hence, there is an urgent need to evaluate the performance of candidate loci for distinguishing between species, especially closely related species, to complement the rbcL + matK combination suggested as the core barcode for land plants. We sampled 48 individuals representing 12 species in Primula sect. Proliferae Pax in China to evaluate the performance of eight leading candidate barcode loci (matK, rbcL, rpoB, rpoC1, trnH-psbA, psbK-psbI, atpFatpH, and internal transcribed spacer (ITS)). The core combination rbcL+matK gave only 50% species resolution in sect. Proliferae. In terms of intraspecies and interspecies divergence, degree of monophyly, and sequence similarity, ITS, trnH-psbA, and psbK-psbI showed good performance as single-locus barcodes. Internal transcribed spacer displayed the highest genetic divergence and best discriminatory power, both alone and in combination with rbcL + matK (83. 3% species resolution). We recommend evaluating the use of ITS for barcoding in other species. Low or single copy nuclear regions would provide more sophisticated barcoding tools in the long term, even though further research is required to find suitable loci. © 2011 Institute of Botany, Chinese Academy of Sciences. Source

Xu D.-L.,U.S. Department of Agriculture | Zhou G.-H.,U.S. Department of Agriculture | Xie Y.-J.,South China Agricultural University | Mock R.,U.S. Department of Agriculture | Li R.,U.S. Department of Agriculture
Virus Genes | Year: 2010

The complete genomic sequence of a Pakistani isolate of Sugarcane streak mosaic virus (SCSMV-PAK) is determined to be 9782 nucleotides in length, excluding the 3′ poly(A) tail, and it comprises a large open reading frame encoding a polyprotein of 3130 amino acid residues. The deduced polyprotein is likely to be cleaved at nine putative protease sites by three viral proteases to ten mature proteins. Conserved motifs of orthologous proteins of other potyviruses are identified in corresponding positions of SCSMV-PAK. The genomic organization is virtually identical to the genera Ipomovirus, Potyvirus, Rymovirus, and Tritimovirus in the family Potyviridae. Sequence analyses indicate that the SCSMV-PAK genomic sequence is different from those of Sugarcane mosaic virus and Sorghum mosaic virus, two viruses with very similar symptoms and host range to SCSMV-PAK. SCSMV-PAK shares 52.7% identity with Triticum mosaic virus (TriMV) and 26.4-31.5% identities with species of the existing genera and unassigned viruses in the Potyviridae at the polyprotein sequence level. Phylogenetic analyses of the polyprotein and deduced mature protein amino acid sequences reveal that SCSMV, together with TriMV, forms a distinct group in the family at the genus level. Therefore, SCSMV should represent a new genus, Susmovirus, in the Potyviridae. © Springer Science+Business Media, LLC 2010. Source

Ji L.,Biomaterials and Biocatalysts Group | Jiang Z.-D.,South China Agricultural University | Liu Y.,Biomaterials and Biocatalysts Group | Koh C.M.J.,Biomaterials and Biocatalysts Group | Zhang L.-H.,National University of Singapore
Fungal Genetics and Biology | Year: 2010

Ustilago maydis is an important model fungal organism for diverse studies. Little improvement has been made in the method for its transformation since the PEG-mediated transfection of spheroplasts that was reported more than 20 years ago. We have constructed binary T-DNA vectors carrying Hygromycin and Nourseothricin resistance gene cassettes and have developed a highly efficient method for transformation of this fungus based on Agrobacterium tumefaciens-mediated transformation (ATMT). Through a series of optimization, at least 1 × 104 Hygromycin B resistant colony forming units (CFU) have been achieved on each 90 mm agar plate using 106 sporidia. Optimal pH value for ATMT is approximately 5.6. Approximately 96% Hygromycin B-resistant transformants contain a single-copy T-DNA inserted into the nuclear genome. Analysis of 204 T-DNA flanking sequences showed that 15.2% of them were found in the coding sequences and a further 37.25% within 0.5 kb from the coding sequences at the 5′ UTR or promoter regions. In addition, a method for preparation and preservation of transformation-ready T-DNA donor and receptor cells has been developed allowing gene tagging experiments to be performed on-demand. An initial screening of 5000 mutants resulted in the identification of a putative farnesyl transferase beta subunit and a PRE6 homologue as new players of sexual mating in U. maydis. © 2010 Elsevier Inc. All rights reserved. Source

Song G.,South China Agricultural University | Liu H.,CAS Shanghai Institute of Materia Medica | Zhang W.,Fudan University | Geng M.,CAS Shanghai Institute of Materia Medica | Li Y.,Fudan University
Bioorganic and Medicinal Chemistry | Year: 2010

A series of anthracene l-rhamnopyranosides were designed and synthesized in a practical way and their cytotoxic activity was examined in vitro. Most compounds exhibited both potent cytotoxicity against several tumor cell lines and high DNA binding capacity. The preliminary results showed that subtle modifications of rhamnosyl moiety in anthracene rhamnosides with acetyl group had a selective toxicity for different tumor cells and the displacement of C-10 carbonyl group in emodin by acetylmethylene group was helpful to improve the inhibitory activity. Lipophilicity of the anthracene glycosides was not a crucial factor for cytotoxicity and most molecules with good cytotoxicity could inhibit the catalytic activity of Top2α. © 2010 Elsevier Ltd. All rights reserved. Source

Qiu H.,South China Agricultural University | Du Y.,South China Normal University | Yao Z.,Sun Yat Sen University
Mathematical Methods in the Applied Sciences | Year: 2013

In this paper, we consider the three-dimensional generalized Boussinesq equations, a system of equations resulting from replacing the Laplacian - Δ in the usual Boussinesq equations by a fractional Laplacian (- Δ)α. We prove the local existence in time and obtain a regularity criterion of solution for the generalized Boussinesq equations by means of the Littlewood-Paley theory and Bony's paradifferential calculus. The results in this paper can be regarded as an extension to the Serrin-type criteria for Navier-Stokes equations and magnetohydrodynamics equations, respectively. Copyright © 2012 John Wiley & Sons, Ltd. Source

Dong X.Y.,South China Agricultural University
Lipids in health and disease | Year: 2012

The molecular mechanism of how cells maintain cholesterol homeostasis has become clearer for the understanding of complicated association between sterol regulatory element-binding proteins (SREBPs), SREBP cleavage-activating protein (SCAP), 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) and Insuin induced-genes (Insigs). The pioneering researches suggested that SREBP activated the transcription of genes encoding HMG-CoA reductase and all of the other enzymes involved in the synthesis of cholesterol and lipids. However, SREBPs can not exert their activities alone, they must form a complex with another protein, SCAP in the endoplasmic reticulum (ER) and translocate to Golgi. Insigs are sensors and mediators that regulate cholesterol homeostasis through binding to SCAP and HMG-CoA reductase in diverse tissues such as adipose tissue and liver, as well as the cultured cells. In this article, we aim to review on the dual functions of Insig protein family in cholesterol homeostasis. Source

Yang S.,South China Agricultural University
Lecture Notes in Electrical Engineering | Year: 2013

High-tech enterprises can enjoy a series of preferential tax policy, so that enterprises are active to apply to be high-tech enterprises. In order to meet the conditions of the declaration, many enterprises pursuit quick success, resulting in producing a lot of problems during their application. Therefore, this paper points out the role, emphasis and difficulty of the high-tech enterprises application and analyzes enterprise management problems, and proposes measures to solve the problems. Finally, it draws the conclusion that enterprise should improve its management system with efforts made in the preapplication assessment and planning, organization of implementation and follow-up management. © 2013 Springer-Verlag. Source

Zhou X.,Zhanjiang Normal University | Jin B.,Zhanjiang Normal University | Li L.,Zhanjiang Normal University | Peng F.,South China University of Technology | And 3 more authors.
Journal of Materials Chemistry | Year: 2012

A carbon nitride/TiO 2 nanotube array (CN/TNT) heterojunction photocatalyst with visible-light response was prepared by a simple electrochemical method. The photocatalyst was characterized by X-ray powder diffraction (XRD), field-emission scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR). The photoelectrochemical properties and photocatalytic activities of the obtained-samples were systematically tested under visible light irradiation. The activity of heterojunction photocatalyst CN/TNTs is higher than that of TNTs. The obviously increased performance of CN/TNTs is ascribed mainly to enhancement of electron-hole separations both at the interface and in the semiconductors. © 2012 The Royal Society of Chemistry. Source

Liu T.-H.,South China Agricultural University
Journal of Forestry Research | Year: 2011

Winter bamboo shoots are widely used in Asian cuisine. We surveyed growth depth (tail depth and root depth), harvest speed, and harvest processes to provide information for developing new harvest technology. The tail depth of most winter bamboo shoots was 100-350 mm below the soil surface, and the root depth was 200-500 mm below the soil surface. Most winter bamboo shoots were difficult to locate with only the naked eye. The digging depth was 200-500 mm to cut winter bamboo shoots from the root. The highest harvest rate was 7. 75 times faster than the slowest one and the average harvest speed ratio of men: women was about 1. 71:1. The harvest process of winter bamboo shoots was divisible into three steps: searching, digging a hole (around the shoot) and cutting the root. The ratio of searching time to the sum of digging and cutting time was about 8:1, showing that searching required more time than digging and cutting together. © 2011 Northeast Forestry University and Springer-Verlag Berlin Heidelberg. Source

Yue L.,CAS Guangzhou Institute of Energy Conversation | Yue L.,Yancheng Institute of Technology | Zhang W.,Yancheng Institute of Technology | Yang J.,South China Agricultural University | Zhang L.,CAS Guangzhou Institute of Energy Conversation
Electrochimica Acta | Year: 2014

A novel Si/porous-C composite with buffering voids was prepared by the co-assembly of phenol-formaldehyde resin, SiO2 and Si nanoparticles, followed by a carbonizing process and subsequent removal of SiO2 template. Si nanoparticle was coated with a layer of porous carbon shell with rationally designed void in between which provides the accommodating space for the volume change of Si over cycling. The as-prepared composite electrode exhibited good electrochemical performances as an anode material in lithium-ion cells, showing a stable reversible capacity of 980 mAh g-1 over 80 cycles with small capacity fade of 0.17%/cycle and high rate capability (721 mAh g-1 at 2000 mA g-1). © 2014 Elsevier Ltd. Source

Jin T.,South China Agricultural University
Genetics and molecular research : GMR | Year: 2012

Functional proteins in larvae of Bactrocera dorsalis, a major fruit pest, play a central role in their resistance to organophosphorus insecticides. Changes in proteins in B. dorsalis larvae after trichlorphon treatment may have a role in the resistance response to trichlorphon. We analyzed 14 protein spots of crude proteins from B. dorsalis larvae post-treatment with trichlorphon in two-dimensional gel electrophoresis through mass spectrometry and protein sequencing. We found functional proteins that are responsible for signal transduction (pkaap and dual specificity tyrosine-phosphorylation-regulated kinase), immunity (hemolectin), synthesis and decomposition (twinstar, cathepsin B, RE66325p), oxidative stress metabolism (glutathione S transferase and CG7320), energy metabolism (Act57B), and cytoskeleton formation (actin). These proteins appear to be involved in the resistance response to trichlorphon. Source

Qiu H.,South China Agricultural University | Shao S.,Nanyang Normal University
Mathematical Methods in the Applied Sciences | Year: 2015

In this paper, we study the ideal incompressible density-dependent Oldroyd model in Rn(n=2,3). We establish local in time existence and uniqueness of solutions for the ideal incompressible density-dependent Oldroyd model. Copyright © 2014 John Wiley & Sons, Ltd. Source

Huang Q.,South China Agricultural University | Wong D.S.,City University of Hong Kong | Susilo W.,University of Wollongong
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2014

How to sign an electronic contract online between two parties (say Alice and Bob) in a fair manner is an interesting problem, and has been studied for a long time. Optimistic Fair Exchange (OFE) is an efficient solution to this problem, in which a semi-trusted third party named arbitrator is called in to resolve a dispute if there is one during an exchange between Alice and Bob. Recently, several extensions of OFE, such as Ambiguous OFE (AOFE) and Perfect AOFE (PAOFE), have been proposed to protect the privacy of the exchanging parties. These variants prevent any outsider including the arbitrator from telling which parties are involved in the exchange of signatures before the exchange completes. However, in PAOFE, AOFE, and all the current work on OFE, the arbitrator can always learn the signer's signature at (or before) the end of a resolution, which is undesirable in some important applications, for example, signing a contract between two parties which do not wish others to find out even when there is a dispute that needs a resolution by the arbitrator. In this work, we introduce a new notion called Privacy-Preserving Optimistic Fair Exchange (P2 OFE), in which other than Alice and Bob, no one else, including the arbitrator, can collect any evidence about an exchange between them even after the resolution of a dispute. We formally define P2 OFE and propose a security model. We also propose a concrete and efficient construction of P2 OFE, and prove its security based on the Strong Diffie-Helllman and Decision Linear assumptions in the standard model. © 2014 Springer International Publishing. Source

Zhuang L.,Guangdong Institute of Eco environmental and Soil Sciences | Zhou S.,Guangdong Institute of Eco environmental and Soil Sciences | Li Y.,South China Agricultural University | Yuan Y.,Guangdong Institute of Eco environmental and Soil Sciences
Bioresource Technology | Year: 2010

In the course of microbial fuel cell (MFC) operation, the acidification of the anode and the alkalization of the cathode inevitably occur, resulting in reduction of the overall performance. In an attempt to reverse the membrane pH gradient, a tubular air-cathode two-chamber MFC was developed that allowed pH adjustment in both compartments. With an anodic pH of 10.0 and a cathodic pH of 2.0, the tubular MFC provided an open circuit voltage of 1.04 V and a maximum power density of 29.9 W/m 3, which were respectively 1.5 and 3.8 times higher than those obtained in the same MFC working at neutral pH. Particularly, the suppression of methanogenesis at high alkaline anode (pH 10.0) contributed to a significant enhancement in coulombic efficiency. The MFC maintained 74% of its performance after 15 days of operation in continuous-flow mode. The appropriate pH adjustment strategy in both compartments ensures a promising improvement in MFC performance. © 2009 Elsevier Ltd. All rights reserved. Source

Ma S.,South China Agricultural University
Information Sciences | Year: 2016

We firstly combine the concepts of public key encryption with equality test (PKEET) and identity-based encryption (IBE) to obtain identity-based encryption with equality test (IBEET). Inheriting the advantage of IBE, IBEET can simplify the certificate management of PKEET with all messages encrypted with the receiver's public identity. In the IBEET scheme, the receiver computes a trapdoor using the secret value for the identity and then sends it to a cloud server for equality test on its ciphertexts with others' ciphertexts. Using this primitive someone with the trapdoor for its identity can delegate out the capability of equality test on its ciphertexts without requiring a central authority to act as a delegator. So it is very suitable for the client with minimal computation resource, e.g, mobile phone. Furthermore, compared with PKEET, it has security improvement since not anyone can perform the test. Therefore, IBEET may have interesting applications in cloud computing, e.g., partition of encrypted emails. We define one-way chosen-ciphertext security against a chosen identity attack (OW-ID-CCA) and propose a construction in bilinear pairing. Finally, extensive security analysis and comparison with related works show that the proposed scheme is proven secure and useful. © 2015 Elsevier Inc. All rights reserved. Source

Li Y.,South China Agricultural University | Li Y.,Tel Aviv University | Pang W.,Guangdong University of Technology | Fu S.,Sun Yat Sen University | Malomed B.A.,Tel Aviv University
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2012

We study two-component solitons and their symmetry-breaking bifurcations (SBBs) in linearly coupled photonic systems with a spatially inhomogeneous strength of the coupling. One system models an inverted virtual photonic crystal, built by periodically doping the host medium with atoms implementing the electromagnetically induced transparency (EIT). In this system, two soliton-forming probe beams with different carrier frequencies are mutually coupled by the EIT-induced effective linear interconversion. The system is described by coupled nonlinear Schrödinger (NLS) equations for the probes, with the linear-coupling constant periodically modulated in space according to the density distribution of the active atoms. The type of the SBB changes from sub- to supercritical with the increase of the total power of the probe beams, which does not occur in systems with constant linear-coupling constants. Qualitatively similar results for the SBB of two-component solitons are obtained, in an exact analytical form, in the model of a fused dual-core waveguide, with the linear coupling concentrated at a point. © 2012 American Physical Society. Source

Zhang Z.,University of California at Davis | Liao H.,South China Agricultural University | Lucas W.J.,University of California at Davis
Journal of Integrative Plant Biology | Year: 2014

As an essential plant macronutrient, the low availability of phosphorus (P) in most soils imposes serious limitation on crop production. Plants have evolved complex responsive and adaptive mechanisms for acquisition, remobilization and recycling of phosphate (Pi) to maintain P homeostasis. Spatio-temporal molecular, physiological, and biochemical Pi deficiency responses developed by plants are the consequence of local and systemic sensing and signaling pathways. Pi deficiency is sensed locally by the root system where hormones serve as important signaling components in terms of developmental reprogramming, leading to changes in root system architecture. Root-to-shoot and shoot-to-root signals, delivered through the xylem and phloem, respectively, involving Pi itself, hormones, miRNAs, mRNAs, and sucrose, serve to coordinate Pi deficiency responses at the whole-plant level. A combination of chromatin remodeling, transcriptional and posttranslational events contribute to globally regulating a wide range of Pi deficiency responses. In this review, recent advances are evaluated in terms of progress toward developing a comprehensive understanding of the molecular events underlying control over P homeostasis. Application of this knowledge, in terms of developing crop plants having enhanced attributes for P use efficiency, is discussed from the perspective of agricultural sustainability in the face of diminishing global P supplies. © 2014 Institute of Botany, Chinese Academy of Sciences. Source

Zhou X.,Zhanjiang Normal University | Jin B.,Zhanjiang Normal University | Chen R.,Zhanjiang Normal University | Peng F.,South China University of Technology | Fang Y.,South China Agricultural University
Materials Research Bulletin | Year: 2013

A facile approach for the preparation of Fe3O 4/g-C3N4 nanospheres with good porous structure has been demonstrated by a hydrothermal method. The as-synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet-visible light (UV-vis) absorbance spectra and X-ray photoelectron spectroscopy (XPS). The photocatalytic decomposition of methyl orange (MO) by the as-prepared samples was carried out under visible light irradiation. The reusability and magnetic properties were also investigated. The results revealed that the porous Fe 3O4/g-C3N4 nanospheres showed considerable photocatalytic activity, and exhibited excellent reusability and magnetic properties with almost no change after five runs. © 2012 Elsevier Ltd. Source

Li C.,Guangdong Academy of Agricultural Sciences | Chen S.,Fujian Academy of Agricultural science | Zuo C.,South China Agricultural University | Sun Q.,Guangdong Academy of Agricultural Sciences | And 3 more authors.
European Journal of Plant Pathology | Year: 2011

Fusarium oxysporum f. sp. cubense (Foc) is the causal pathogen of Fusarium wilt of banana. To understand infection of banana roots by Foc race 4, we developed a green fluorescent protein (GFP)-tagged transformant and studied pathogenesis using fluorescence microscopy and confocal laser scanning microscopy. The transformation was efficient, and GFP expression was stable for at least six subcultures with fluorescence clearly visible in both hyphae and spores. The transformed Foc isolate also retained its pathogenicity and growth pattern, which was similar to that of the wild type. The study showed that: (i) Foc race 4 was capable of invading the epidermal cells of banana roots directly; (ii) potential invasion sites include epidermal cells of root caps and elongation zone, and natural wounds in the lateral root base; (iii) in banana roots, fungal hyphae were able to penetrate cell walls directly to grow inside and outside cells; and (iv) fungal spores were produced in the root system and rhizome. To better understand the interaction between Foc race 4 and bananas, nine banana cultivars were inoculated with the GFP-transformed pathogen. Root exudates from these cultivars were collected and their effect on conidia of the GFP-tagged Foc race 4 was determined. Our results showed that roots of the Foc race 4-susceptible banana plants were well colonized with the pathogen, but not those of the Foc race 4-resistant cultivars. Root exudates from highly resistant cultivars inhibited the germination and growth of the Fusarium wilt pathogen; those of moderately resistant cultivars reduced spore germination and hyphal growth, whereas the susceptible cultivars did not affect fungal germination and growth. The results of this work demonstrated that GFP-tagged Foc race 4 isolates are an effective tool to study plant-fungus interactions that could potentially be used for evaluating resistance in banana to Foc race 4 by means of root colonization studies. Banana root exudates could potentially also be used to identify cultivars in the Chinese Banana Germplasm Collection with resistance to the Fusarium wilt pathogen. © 2011 KNPV. Source

Liu X.,Guangdong Polytechnic Normal University | Fu H.,Guangdong Polytechnic Normal University | Du Z.,South China Agricultural University
Computational Intelligence and Neuroscience | Year: 2016

Relation extraction is one of the important research topics in the field of information extraction research. To solve the problem of semantic variation in traditional semisupervised relation extraction algorithm, this paper proposes a novel semisupervised relation extraction algorithm based on ensemble learning (LXRE). The new algorithm mainly uses two kinds of support vector machine classifiers based on tree kernel for integration and integrates the strategy of constrained extension seed set. The new algorithm can weaken the inaccuracy of relation extraction, which is caused by the phenomenon of semantic variation. The numerical experimental research based on two benchmark data sets (PropBank and AIMed) shows that the LXRE algorithm proposed in the paper is superior to other two common relation extraction methods in four evaluation indexes (Precision, Recall, F -measure, and Accuracy). It indicates that the new algorithm has good relation extraction ability compared with others. © 2016 Xiaoyong Liu et al. Source

Zhuang L.,Guangdong Institute of Eco environmental and Soil Sciences | Feng C.,South China University of Technology | Zhou S.,Guangdong Institute of Eco environmental and Soil Sciences | Li Y.,South China Agricultural University | Wang Y.,Guangdong Institute of Eco environmental and Soil Sciences
Process Biochemistry | Year: 2010

The aim of this study is to compare the performance of different membrane cathode assembly (MCA) and cloth-cathode assembly (CCA) in air-chamber microbial fuel cells (MFCs) and provide an optimum cathode configuration for MFC scaling up. Two MCAs were prepared by hot-pressing carbon cloth containing cathodic catalyst to anion exchange membrane (AEM) and cation exchange membrane (CEM), respectively. A CCA was built by coating GORE-TEX ® cloth with a mixture of nickel-based conductive paint and cathodic catalyst. Under the fed-batch mode using brewery wastewater, the MFCs were compared with respect to power production, coulombic efficiency, COD removal, internal resistance and material cost. The experimental results show that CCA is a more favorable alternative than MCAs due to its easier preparation, higher maximum power density and COD removal, and lower internal resistance and cost. The optimum cathode assembly of CCA is cost-effective and mechanically robust enough to meet the important requirements for MFC scalability. © 2010 Elsevier Ltd. All rights reserved. Source

Liu T.H.,South China Agricultural University
Advanced Materials Research | Year: 2011

A mechanical litchi picking process using a cut-clamp combined picker was modeled. A minimum clamping velocity model is required to ensure such a picker working reliably as well as to limit consumed energy. The picking process was sub-divided into seven stages. Three variables, namely the width of fiction head (D), the press on the clamping head(N) and fiction index between fruit branch( μk (v)) were chosen as independent variables. The output of modeling is the minimum cutting (or clamping) velocity. The model was verified using the experimental results of cutting and clamping by a simulated cut-clamp combined picker. The experimental results also showed if setting safety factor k=1.5, calculated velocities can ensure fruit branch be clamped firmly by the cut-clamp combined picker. © (2011) Trans Tech Publications. Source

Zhang Y.,University of Florida | Jalan N.,University of Florida | Zhou X.,University of Florida | Goss E.,University of Florida | And 4 more authors.
ISME Journal | Year: 2015

Understanding the evolutionary history and potential of bacterial pathogens is critical to prevent the emergence of new infectious bacterial diseases. Xanthomonas axonopodis subsp. Citri (Xac) (synonym X. Citri subsp. Citri), which causes citrus canker, is one of the hardest-fought plant bacterial pathogens in US history. Here, we sequenced 21 Xac strains (14 XacA, 3 XacA∗ and 4 XacAw) with different host ranges from North America and Asia and conducted comparative genomic and evolutionary analyses. Our analyses suggest that acquisition of beneficial genes and loss of detrimental genes most likely allowed XacA to infect a broader range of hosts as compared with XacAw and XacA∗. Recombination was found to have occurred frequently on the relative ancient branches, but rarely on the young branches of the clonal genealogy. The ratio of recombination/ mutation ρ/θ was 0.0790±0.0005, implying that the Xac population was clonal in structure. Positive selection has affected 14% (395 out of 2822) of core genes of the citrus canker-causing Xanthomonas. The genes affected are enriched in 'carbohydrate transport and metabolism' and 'DNA replication, recombination and repair' genes (Po0.05). Many genes related to virulence, especially genes involved in the type III secretion system and effectors, are affected by positive selection, further highlighting the contribution of positive selection to the evolution of citrus canker-causing Xanthomonas. Our results suggest that both metabolism and virulence genes provide advantages to endow XacA with higher virulence and a wider host range. Our analysis advances our understanding of the genomic basis of specialization by positive selection in bacterial evolution. © 2015 International Society for Microbial Ecology All rights reserved. Source

Xu C.,South China Agricultural University | Takac T.,Palacky University | Burbach C.,University of Bonn | Menzel D.,University of Bonn | Samaj J.,Palacky University
BMC Plant Biology | Year: 2011

Background: Hydroxyproline rich glycoproteins (HRGPs) are implicated to have a role in many aspects of plant growth and development but there is limited knowledge about their localization and function during somatic embryogenesis of higher plants. In this study, the localization and function of hydroxyproline rich glycoproteins in embryogenic cells (ECs) and somatic embryos of banana were investigated by using immunobloting and immunocytochemistry with monoclonal JIM11 and JIM20 antibodies as well as by treatment with 3,4-dehydro-L-proline (3,4-DHP, an inhibitor of extensin biosynthesis), and by immunomodulation with the JIM11 antibody.Results: Immunofluorescence labelling of JIM11 and JIM20 hydroxyproline rich glycoprotein epitopes was relatively weak in non-embryogenic cells (NECs), mainly on the edge of small cell aggregates. On the other hand, hydroxyproline rich glycoprotein epitopes were found to be enriched in early embryogenic cells as well as in various developmental stages of somatic embryos. Embryogenic cells (ECs), proembryos and globular embryos showed strong labelling of hydroxyproline rich glycoprotein epitopes, especially in their cell walls and outer surface layer, so-called extracellular matrix (ECM). This hydroxyproline rich glycoprotein signal at embryo surfaces decreased and/or fully disappeared during later developmental stages (e.g. pear-shaped and cotyledonary stages) of embryos. In these later developmental embryogenic stages, however, new prominent hydroxyproline rich glycoprotein labelling appeared in tri-cellular junctions among parenchymatic cells inside these embryos. Overall immunofluorescence labelling of late stage embryos with JIM20 antibody was weaker than that of JIM11. Western blot analysis supported the above immunolocalization data. The treatment with 3,4-DHP inhibited the development of embryogenic cells and decreased the rate of embryo germination. Embryo-like structures, which developed after 3,4-DHP treatment showed aberrant non-compact epidermis with discontinuous ECM at the outer surface as well as much less immunolabelling with the JIM11 antibody. This treatment also decreased the plant regeneration capacity in embryogenic banana cultures. Finally, immunomodulation of surface hydroxyproline rich glycoproteins by co-culture of embryos with the JIM11 antibody resulted in a much lower germination capacity of these embryos.Conclusions: These results suggest that hydroxyproline rich glycoproteins play an important developmental role, especially in the process of regeneration and germination of embryos during plant regeneration via somatic embryogenesis. Proper content and localization of hydroxyproline rich glycoproteins seem to be essential for the formation and regeneration of banana somatic embryos. © 2011 Xu et al; licensee BioMed Central Ltd. Source

Shen G.,Louisiana State University Health Sciences Center | Shen G.,University of Texas Health Science Center at San Antonio | Zhou E.,Louisiana State University Health Sciences Center | Zhou E.,South China Agricultural University | And 2 more authors.
Eukaryotic Cell | Year: 2012

Human Wiskott-Aldrich syndrome protein (WASP) is a scaffold linking upstream signals to the actin cytoskeleton. In response to intersectin ITSN1 and Rho GTPase Cdc42, WASP activates the Arp2/3 complex to promote actin polymerization. The human pathogen Cryptococcus neoformans contains the ITSN1 homolog Cin1 and the WASP homolog Wsp1, which share more homology with human proteins than those of other fungi. Here we demonstrate that Cin1, Cdc42/Rac1, and Wsp1 function in an effector pathway similar to that of mammalian models. In the cin1 mutant, expression of the autoactivated Wsp1-B-GBD allele partially suppressed the mutant defect in endocytosis, and expression of the constitutively active CDC42 Q61L allele restored normal actin cytoskeleton structures. Similar phenotypic suppression can be obtained by the expression of a Cdc42-green fluorescent protein (GFP)-Wsp1 fusion protein. In addition, Rac1, which was found to exhibit a role in early endocytosis, activates Wsp1 to regulate vacuole fusion. Rac1 interacted with Wsp1 and depended on Wsp1 for its vacuolar membrane localization. Expression of the Wsp1-B-GBD allele restored vacuolar membrane fusion in the rac1 mutant. Collectively, our studies suggest novel ways in which this pathogenic fungus has adapted conserved signaling pathways to control vesicle transport and actin organization, likely benefiting survival within infected hosts. © 2012, American Society for Microbiology. Source

Golovatch S.I.,RAS A.N. Severtsov Institute of Ecology and Evolution | Li Y.,Guangxi Normal University | Liu W.,South China Agricultural University | Geoffroy J.-J.,CNRS Science Conservation Center
ZooKeys | Year: 2012

The large Southeast Asian genus Desmoxytes is slightly rediagnosed. A number of troglomorphic, most likely troglobitic, species occur in southern China. A key is provided to all 10 Desmoxytes spp. currently known from China, including three new presumed troglobites: D. eupterygota sp. n. from Hunan Province, as well as D. spinissima sp. n. and D. lui sp. n. from Guangxi Province. "Desmoxytes" philippina Nguyen Duc & Sierwald, 2010, from the Philippines, is formally removed from Desmoxytes, but not assigned to another genus. It probably belongs in a new genus in the subfamily Australiosomatinae, tribe Antichiropodini, close to the Bornean Euphyodesmus Attems, 1931 and Borneochiropus Golovatch, 1996. © Sergei I. Golovatch et al. Source

Wang C.,Institute of Molecular and Cell Biology | Ye F.,Nanyang Technological University | Kumar V.,Nanyang Technological University | Gao Y.-G.,Institute of Molecular and Cell Biology | And 3 more authors.
Nucleic Acids Research | Year: 2014

Pseudomonas aeruginosa relies on cell motility and ability to form biofilms to establish infections; however, the mechanism of regulation remains obscure. Here we report that BswR, a xenobiotic response element-type transcriptional regulator, plays a critical role in regulation of bacterial motility and biofilm formation in P. aeruginosa. Transcriptomic and biochemical analyses showed that BswR counteracts the repressor activity of MvaT, controls the transcription of small RNA rsmZ and regulates the biogenesis of bacterial flagella the crystal structure of BswR was determined at 2.3 Å resolution; the monomer comprises a DNA-binding domain with a helix-turn-helix motif in the N terminus and two helices (α6 and α7) with a V-shaped arrangement in the C-terminus. In addition to the contacts between the parallel helices α5 of two monomers, the two helical extensions (α6 and α7) intertwine together to form a homodimer, which is the biological function unit. Based on the result of DNase I protection assay together with structural analysis of BswR homodimer, we proposed a BswR-DNA model, which suggests a molecular mechanism with which BswR could interact with DNA. Taken together, our results unveiled a novel regulatory mechanism, in which BswR controls the motility and biofilm formation of P. aeruginosa by modulating the transcription of small RNA rsmZ. © 2014 The Author(s). Published by Oxford University Press. Source

Li Y.,Guangdong AIB Polytechnic College | Zhao Z.,South China Agricultural University | Gao J.,Guangdong AIB Polytechnic College
Shuju Caiji Yu Chuli/Journal of Data Acquisition and Processing | Year: 2012

An efficient design for attitude measurement system is presented. The system has main features as follows: monitoring the attitude angles by fusing one tri-axial accelerometer and one tri-axial gyroscope integrated in ADIS16355 (MEMS inertial sensor module), collecting information and calculating attitude angles by using ARM7v7 processor Cotex-M3. The compensation of the whole attitude measurement system are presented, as well as the function of ADIS16355 and their installation on the object. Then, one Kalman filter is designed as a sensor data fusion method for measuring real-time attitude angles. Finally, based on the comparisons between fused data and reference data from an AHRS500GA instrument, experimental resultsshow that the proposed fusion method gives quite accurate attitude information of the controlled object and the average error of attitude measurement is ±1°. Source

Xu Z.,South China Agricultural University | Olmi M.,University of Tuscia | He J.,Zhejiang University
Florida Entomologist | Year: 2011

Anteon nanlingense sp. nov. and Anteon longum sp. nov. are described from Nanling National Nature Reserve (Guangdong, P.R. China). A check-list of Dryinidae from Nanling National Nature Reserve is presented. Source

Hu H.Q.,Guangdong Ocean University | Li X.S.,South China Agricultural University | He H.,Guangdong Ocean University
Biological Control | Year: 2010

Understanding the mechanisms of the antagonistic endophytic bacteria is helpful in controlling plant diseases. An endophytic bacterium, Bg-C31, from mangrove was found to be antagonistic to some fungal and bacterial pathogens of plants and to be effective in the biocontrol of Capsicum bacterial wilt in pot and field trials. Bg-C31 was identified as Bacillus amyloliquefaciens by biochemical and physiological tests as well as sequences of 16S rDNA and the LCI gene. The antimicrobial substance produced by Bg-C31 was identified as a protein, which is resistant to protease k and heat, by ammonium sulfate precipitation and butanol extraction. The antagonistic gene was located in the chromosome by plasmid curing. A 29. kDa fusion protein of the LCI gene was expressed. Antimicrobial activity of the fusion protein to Ralstonia solanacearum was detected on gels in situ, indicating that the LCI gene could potentially be used to produce transgenic plants that are resistant to bacterial infection. © 2010. Source

Wang L.,South China Agricultural University | Chen J.,U.S. Department of Agriculture
Journal of Chemical Ecology | Year: 2015

Red imported fire ants, Solenopsis invicta, are significant invasive pests. Certain native ant species can compete with S. invicta, such as the little black ant, Monomorium minimum. Defensive secretions may contribute to the competition capacity of native ants. The chemistry of ant defensive secretions in the genus Monomorium has been subjected to extensive research. The insecticidal alkaloids, 2,5-dialkyl-pyrrolidines and 2,5-dialkyl-pyrrolines have been reported to dominate the venom of M. minimum. In this study, analysis of defensive secretions of workers and queens of M. minimum revealed two primary amines, decylamine and dodecylamine. Neither amine has been reported previously from natural sources. Toxicity and digging suppression by these two amines against S. invicta were examined. Decylamine had higher toxicity to S. invicta workers than dodecylamine, a quicker knockdown effect, and suppressed the digging behavior of S. invicta workers at lower concentration. However, the amount of fatty amines in an individual ant was not enough to knockdown a fire ant or suppress its digging behavior. These amines most likely work in concert with other components in the chemical defense of M. minimum. © 2015, Springer Science+Business Media New York (outside the USA). Source

Zhang W.,Hunan University | Liu Z.,Hunan University | Liu Z.,South China Agricultural University
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2011

It is of great significance to proceed variable rate spray (VRS) according to the requirement of crops for saving pesticide and protecting environment. A hand-push sprayer of type 3WY-A3 was tested with the VRS system on real-time mixing pesticide. The VRS system includes a mixing pesticide device, a differential pressure (DP) flow meter, a flow control valve and control hardware and software. The experimental results showed that the pesticide flow range was from 0.1 to 0.9 mL/s with control accuracy of ±5%. Source

Guo Z.,South China Agricultural University
Advanced Materials Research | Year: 2012

A realistic quantum magnetic disk structure formed by a nanowire array is studied. The length fluctuation of the nanowires is described with Gaussian distributions. The magnetostatic interaction between two nanowires with different length and radius is derived. Based on that, we study the thermal stability of the nanowire array analytically and numerically by the damage spreading technique. The results show that when the magnetic cell's spacing reduces (the storage density increases) or the nanowire length increases, damage spreading becomes difficult and the system stability is enhanced. In addition, the long-range magnetostatic interaction and the shape anisotropy make the system more stable and the nanowire length fluctuation influence is comparatively small. © (2012) Trans Tech Publications, Switzerland. Source

Li Y.,Tel Aviv University | Li Y.,South China Agricultural University | Pang W.,Guangdong University of Technology | Malomed B.A.,Tel Aviv University
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2012

We study modes trapped in a rotating ring carrying the self-focusing (SF) or self-defocusing (SDF) cubic nonlinearity and double-well potential cos2θ, where θ is the angular coordinate. The model, based on the nonlinear Schrödinger (NLS) equation in the rotating reference frame, describes the light propagation in a twisted pipe waveguide, as well as in other optical settings, and also a Bose-Einstein condensate (BEC) trapped in a torus and dragged by the rotating potential. In the SF and SDF regimes, five and four trapped modes of different symmetries are found, respectively. The shapes and stability of the modes and the transitions between them are studied in the first rotational Brillouin zone. In the SF regime, two symmetry-breaking transitions are found, of subcritical and supercritical types. In the SDF regime, an antisymmetry-breaking transition occurs. Ground states are identified in both the SF and SDF systems. © 2012 American Physical Society. Source

Huang Z.,South China University of Technology | Huang Z.,Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters | Huang Z.,Key Laboratory Of Environmental Protect And Eco Remediation Of Guangdong Regular Higher Education Institutions | Wu P.,South China University of Technology | And 6 more authors.
Journal of Materials Chemistry A | Year: 2014

The synthesis of a layer-by-layer ordered nanohybrid with a sandwich structure was based on electrostatically driven self-assembly between the negatively charged carboxyl graphene monolayer and the positively charged ZnAl-layered double hydroxide nanosheets. The characteristics of the layer-by-layer ordered nanohybrid were investigated by SEM, TEM, AFM and XRD. The enhanced photocatalytic activity of the calcined product was determined by the photocatalytic degradation of the cationic dye methylene blue (MB) and anionic dye orange G (OG) under visible light. The enhanced photocatalytic efficiency was mainly attributed to the effective electronic coupling between graphene and calcined ZnAl-LDH. Additionally, the chemical stability of the calcined ZnAl-LDH is significantly improved by hybridization of graphene and this is attributed to the protection provided by the close contacted graphene with highly stability. This work also establishes a simple method for fabricating graphene-based nanohybrids with a sandwich structure. © 2014 the Partner Organisations. Source

Hu Q.,South China Agricultural University
Journal of Nonlinear Mathematical Physics | Year: 2011

We consider a periodic 2-component CamassaHolm equation with vorticity in the paper. We first give the local well-posedness and the blow-up criterion for strong solutions to the equation in the Sobolev space H s, s > \frac{3}{2}. We then present a global existence result for strong solutions to the equation. We finally obtain several blow-up results and the blow-up rate of strong solutions to the equation. We finally examine the propagation behaviour of compactly supported solutions to the equation. The obtained results cover and improve the earlier results for a periodic 2-component CamssaHolm equation without vorticity. © 2011 B. Kruglikov. Source

Pan S.-H.,South China Agricultural University | Pan S.-H.,CAS Guangzhou Institute of Geochemistry | Li J.,CAS Guangzhou Institute of Geochemistry | Lin T.,CAS Guangzhou Institute of Geochemistry | And 3 more authors.
Environmental Pollution | Year: 2012

Organic films were collected from indoor and outdoor window surfaces in two large cities in southern China, Guangzhou and Hong Kong, and analyzed to quantify the polycyclic aromatic hydrocarbons (PAHs). In the glass films, the highest concentration of total PAHs, predominantly phenanthrene, fluorene, fluoranthene, and pyrene, was found to be l400 ng/m 2. The concentrations of PAHs in Guangzhou were usually higher than those in Hong Kong. In general, higher concentrations of PAHs on exterior window films in comparison with interior window films in both cities indicated that the outdoor air acted as a major source of pollution to the indoor environment. However, indoor air was a major source of some light-weight PAHs. Measurements made over time indicated that the growth rates of light-weight PAHs on window surfaces were fast at the beginning and then gradually reached a consistent level, whereas heavy-weight PAHs exhibited near-linear accumulation during the 40 days sampling period. © 2012 Elsevier Ltd. All rights reserved. Source

Situ H.,South China Agricultural University
Quantum Information Processing | Year: 2014

We present a quantum approach to play asymmetric coordination games, which are more general than symmetric coordination games such as the Battle of the Sexes game, the Chicken game and the Hawk-Dove game. Our results show that quantum entanglement can help the players to coordinate their strategies. © 2013 Springer Science+Business Media New York. Source

Wang H.,Cornell University | Wang H.,South China Agricultural University | Ma F.,Cornell University | Cheng L.,Cornell University
Planta | Year: 2010

Metabolite profiles and activities of key enzymes in the metabolism of organic acids, nitrogen and amino acids were compared between chlorotic leaves and normal leaves of 'Honeycrisp' apple to understand how accumulation of non-structural carbohydrates affects the metabolism of organic acids, nitrogen and amino acids. Excessive accumulation of non-structural carbohydrates and much lower CO 2 assimilation were found in chlorotic leaves than in normal leaves, confirming feedback inhibition of photosynthesis in chlorotic leaves. Dark respiration and activities of several key enzymes in glycolysis and tricarboxylic acid (TCA) cycle, ATP-phosphofructokinase, pyruvate kinase, citrate synthase, aconitase and isocitrate dehydrogenase were significantly higher in chlorotic leaves than in normal leaves. However, concentrations of most organic acids including phosphoenolpyruvate (PEP), pyruvate, oxaloacetate, 2-oxoglutarate, malate and fumarate, and activities of key enzymes involved in the anapleurotic pathway including PEP carboxylase, NAD-malate dehydrogenase and NAD-malic enzyme were significantly lower in chlorotic leaves than in normal leaves. Concentrations of soluble proteins and most free amino acids were significantly lower in chlorotic leaves than in normal leaves. Activities of key enzymes in nitrogen assimilation and amino acid synthesis, including nitrate reductase, glutamine synthetase, ferredoxin and NADH-dependent glutamate synthase, and glutamate pyruvate transaminase were significantly lower in chlorotic leaves than in normal leaves. It was concluded that, in response to excessive accumulation of non-structural carbohydrates, glycolysis and TCA cycle were up-regulated to "consume" the excess carbon available, whereas the anapleurotic pathway, nitrogen assimilation and amino acid synthesis were down-regulated to reduce the overall rate of amino acid and protein synthesis. © 2010 Springer-Verlag. Source

Zhang J.,Guangdong Pharmaceutical University | Zhang J.,Biomedical Research Institute | Lu Y.,Biomedical Research Institute | Yue X.,Biomedical Research Institute | And 6 more authors.
PLoS ONE | Year: 2013

Emerging evidence indicate that microRNAs (miRNAs) may play important roles in cancer. Aberrant expression of miRNAs has been frequently identified in different human malignancies, including colorectal cancer (CRC). However, the mechanism by which deregulated miRNAs impact the development of CRC remains largely elusive. In this study, we show that miR-124 is significantly down-regulated in CRC compared to adjacent non-tumor colorectal tissues. MiR-124 suppresses the expression of STAT3 by directly binding to its 3′-untranslated region (3′-UTR). Overexpression of miR-124 led to increased apoptosis of CRC cells and reduced tumor growth in vitro and in vivo. Knocking down STAT3 expression by specific siRNA suppressed the growth of CRC cells in vitro and in vivo, resembling that of miR-124 overexpression. Moreover, overexpression of STAT3 in miR-124-transfected CRC cells effectively rescued the inhibition of cell proliferation caused by miR-124. These data suggest that miR-124 serves as a tumor suppressor by targeting STAT3, and call for the use of miR-124 as a potential therapeutic tool for CRC, where STAT3 is often hyper-activated. © 2013 Zhang et al. Source

Li C.,South China Agricultural University
International Journal of Food Engineering | Year: 2010

Deep-bed drying is an integrated process affected by many different factors. In this regard, the nature of deep-bed drying phenomenon was discussed, and the models and mass equilibrium equations for deep-bed hot-air drying process were constructed for the study. The material dehydration process, medium humidification process and system equilibrium were analyzed. The dimensionless numbers were introduced to simplify and solve the differential equations of deep-layer drying. Furthermore, the analytical formula and solution of the deep layer hot-air drying process were given. The results provided a kind of simple and practical analytical formula and calculation method, which are the base to hold the characteristics of deep-layer drying system well, and realize the accurate control of process. Copyright © 2010 The Berkeley Electronic Press. All rights reserved. Source

Zhong J.,Jinan University | Weng J.,Jinan University | Weng J.,South China Agricultural University
Optics Express | Year: 2010

A generalized Fourier analysis, by use of an adaptive multiscale windowed Fourier transform (AWFT), has been presented for the phase retrieval of fringe patterns. The Fourier transform method can be considered as a special case of AWFT method with a maximum window. The instantaneous frequency of the local signal is introduced to estimate whether the condition for separating the first spectrum component is satisfied for the phase retrieval of fringe patterns. The adaptive window width for this algorithm is determined by the length of the local stationary fringe pattern in order to balance the frequency and space resolution. The local stationary length of fringe pattern is defined as the signal satisfying the condition that whose first spectrum component is separated from all the other spectra within the local spatial area. In comparison with Fourier transform, fixed windowed Fourier transform and wavelet transform in numerical simulation and experiment, the adaptive multiscale windowed Fourier transform can present more accurate results of phase retrieval. © 2010 Optical Society of America. Source

Zhu H.,Guangdong Institute of Microbiology | Guo J.,Guangdong Institute of Microbiology | Chen M.,Guangdong Institute of Microbiology | Feng G.,Guangdong Institute of Microbiology | Yao Q.,South China Agricultural University
PLoS ONE | Year: 2012

Heavy-metal-tolerant bacteria, GIMN1.004T, was isolated from mine soils of Dabaoshan in South China, which were acidic (pH 2-4) and polluted with heavy metals. The isolation was Gram-negative, aerobic, non-spore-forming, and rod-shaped bacteria having a cellular width of 0.5-0.6 μm and a length of 1.3-1.8 μm. They showed a normal growth pattern at pH 4.0-9.0 in a temperature ranging from 5°C to 40°C.The organism contained ubiquinone Q-8 as the predominant isoprenoid quinine, and C16:0, summed feature 8 (C18:1ω7c and C18:1ω6c), C18:0, summed feature 3 (C16:1ω7c or iso-C15:0 2-OH), C17:0 cyclo, C18:1ω9c, C19:0 cyclo ω8c, C14:0 as major fatty acid. These profiles were similar to those reported for Burkholderia species. The DNA G+C % of this strain was 61.6%. Based on the similarity to 16S rRNA gene sequence, GIMN1.004T was considered to be in the genus Burkholderia. The similarities of 16S rRNA gene sequence between strain GIMN1.004T and members of the genus Burkholderia were 96-99.4%, indicating that this novel strain was phylogenetically related to members of that genus. The novel strain showed the highest sequence similarities to Burkholderia soli DSM 18235T (99.4%); Levels of DNA-DNA hybridization with DSM 18235T was 25%. Physiological and biochemical tests including cell wall composition analysis, differentiated phenotype of this strain from that closely related Burkholderia species. The isolation had great tolerance to cadmium with MIC of 22 mmol/L, and adsorbability of 144.94 mg/g cadmium,and it was found to exhibit antibiotic resistance characteristics. The adsorptive mechanism of GIMN1.004T for cadmium depended on the action of the amide,carboxy and phosphate of cell surface and producing low-molecular-weight (LMW) organic acids to complex or chelated Cd2+.Therefore, the strain GIMN1.004T represented a new cadmium resistance species, which was tentatively named as Burkholderia dabaoshanensis sp. nov. The strain type is GIMN1.004T (= CCTCC M 209109T = NRRL B-59553T). © 2012 Zhu et al. Source

Tang H.,South China Agricultural University | Vanderploeg H.A.,National Oceanic and Atmospheric Administration | Johengen T.H.,University of Michigan | Liebig J.R.,National Oceanic and Atmospheric Administration
Journal of Great Lakes Research | Year: 2014

Experiments from May to December measuring selective grazing and egestion of different phytoplankton taxa in natural Saginaw Bay (Lake Huron) seston by shallow-water morph quagga mussels (Dreissena bugensis rostriformis) showed that the mussels were highly selective filter feeders and that their net clearance rates on different species ranged widely, resulting in food consumption that was strongly driven by seasonal phytoplankton dynamics. Overall, net clearance rates by quagga mussels on the entire phytoplankton assemblage were similar to those observed for zebra mussels (Dreissena polymorpha) during the 1990s. Phytoplankton taxon, rather than size, was more important to food selection since quagga mussels cleared similar sized but different species of algae at very different rates. In contrast to many studies with zebra mussels, larger-sized algae such as Dinobryon divergens, Aulacoseira italica, Fragilaria crotonensis, and Anabaena were cleared at high rates and rejected at lower rates than many smaller species within the same broad taxonomic group. We suspect that these differences between dreissenid species do not stem from species differences but methodological factors and phytoplankton composition of systems studied. Small-sized diatoms, green algae with thick cell walls (Scenedesmus and Oocystis), and colonial cyanobacteria with gelatinous sheaths (Aphanocapsa, Chroococcus, and Microcystis) were cleared at low rates and rejected in high proportion in pseudofeces or feces during all seasons. We describe the likely mechanisms of pre- and post-ingestive behavior that explain these differences, which relate to phytoplankton size, morphology, cell wall characteristics, and chemical composition. Changes in the Great Lakes phytoplankton communities are consistent with mussel grazing preferences. © 2013. Source

Xu Z.,South China Agricultural University | Olmi M.,University of Tuscia | Guglielmino A.,University of Tuscia | Dong W.,Anhui Academy of Agricultural Sciences
Journal of the Kansas Entomological Society | Year: 2011

A new species of the genus Aphelopus Dalman (Hymenoptera: Dryinidae) from Yunnan Province, China is described and illustrated. Existing keys to species are revised to incorporate A. alebroides, new species. The new species is a parasitoid of an unidentified species of Alebroides Matsumura (Hemiptera: Cicadellidae: Typhlocybinae) feeding on Zanthoxylum bungeanum Maximowicz (Rutaceae) (Chinese prickly-ash; Sichuan pepper tree). © 2011 Kansas Entomological Society. Source

Li Y.-W.,Sun Yat Sen University | Li X.,Sun Yat Sen University | Xiao X.-X.,Sun Yat Sen University | Zhao F.,Chinese Academy of Fishery Sciences | And 3 more authors.
Developmental and Comparative Immunology | Year: 2014

Tumor necrosis factor receptor (TNFR)-associated factor 6 (TRAF6) is a crucial signal transducer in both the TNFR superfamily and Toll-like receptor/interleukin 1R family. Although significant progress has been made in clarifying the role of TRAF6 in mammals, the function of TRAF6 in fish is still poorly understood. In this study, we cloned the orange-spotted grouper (Epinephelus coioides) TRAF6 (EcTRAF6) cDNA, with an open reading frame of 1713. bp encoding 570 amino acids. Sequence analysis indicated that EcTRAF6 contains the four characteristic domains conserved in the TRAF family, including an N-terminal RING finger, two zinc fingers, a coiled-coil domain, and a C-terminal MATH domain. Homology alignment and phylogenetic analysis demonstrated that EcTRAF6 shares high sequence identity with TRAF6 of other fish species. The EcTRAF6 gene contains seven exons and six introns, which is similar to the organization in ayu, but not in the common carp, human, or mouse (six exons and five introns). EcTRAF6 transcripts were broadly expressed in all tissues tested, and increased after infection with Cryptocaryon irritans. Intracellular localization showed EcTRAF6 was distributed mainly in the cytoplasm. Over-expression of wild type (WT) EcTRAF6, truncated forms of EcTRAF6, including δZinc finger 2 and δMATH, and a mutant of C78A activated NF-κB strongly in HEK293T cells; whereas truncations, including δRING, δZinc finger 1 and δcoiled-coiled, and a mutant of K132R induced the activity of NF-κB slightly compared to WT EcTRAF6, implying the latter has a more crucial role in downstream signal transduction. Together, these results suggested EcTRAF6 functions like that of mammals to activate NF-κB, and it might have an important role in host defense against parasitic infections. © 2013 Elsevier Ltd. Source

Huang X.-Z.,Sun Yat Sen University | Li Y.-W.,Sun Yat Sen University | Mai Y.-Z.,Sun Yat Sen University | Luo X.-C.,South China University of Technology | And 2 more authors.
Developmental and Comparative Immunology | Year: 2014

Nonspecific cytotoxic cells (NCCs) are an important cytotoxic cell population in the innate teleost immune system. The receptor designated "NCC receptor protein 1" (NCCRP-1) has been reported to be involved in the recognition and activation of NCCs. In this study, the full-length cDNA of Epinephelus coioides NCCRP-1 (ecnccrp-1) was cloned. The open reading frame (ORF) of ecnccrp-1 is 699bp, encoding a 232 amino acid protein that includes proline-rich motifs at the N-terminus and is related to the F-box associated family. Although a bioinformatics analysis showed that EcNCCRP-1 had no signal peptide or transmembrane helices, a polyclonal antibody directed against recombinant EcNCCRP-1 efficiently labeled a membrane protein in the head kidney, detected with Western blot analysis, which indicated that the protein localized to the cell surface. RT-PCR showed that the constitutive expression of ecnccrp-1 was higher in the lymphoid organs, such as the trunk kidney, spleen, head kidney, and thymus, and lower in brain, heart, fat, liver, muscle, and skin. After infection with Cryptocaryon irritans, the transcription of ecnccrp-1 was analyzed at the infected sites (skin and gills) and in the systemic immune organs (head kidney and spleen). At the infected sites, especially the skin, ecnccrp-1 expression was upregulated at 6h post infection, reaching peak expression on day 3 post the primary infection. However, the expression patterns differed in the systemic immune organs. In the spleen, ecnccrp-1 was gradually increased in the early infection period and decreased sharply on day 3 post the primary infection, whereas in the head kidney, the transcription of ecnccrp-1 was depressed during almost the whole course of infection. An immunohistochemical analysis showed that EcNCCRP-1+ cells accumulated at the sites of infection with C. irritans. These results suggested that NCCs were involved in the process of C. irritans infection in E. coioides. © 2014. Source

Wu W.-H.,CAS Institute of Botany | Wu W.-H.,South China Agricultural University | Meng T.,CAS Institute of Botany | Xu W.-B.,CAS Institute of Botany | And 2 more authors.
Phytotaxa | Year: 2012

A new species of Gesneriaceae from Southwest Guangxi, China is described here as Primulina sinovietnamica. This previously unknown species is morphologically similar to P. pungentisepala and P. ningmingensis, but can be distinguished from the latter two taxa by several non-overlapping morphological characters. This hypothesis is consistent with the molecular phylogenetic tree based on sequences of the chloroplast matK gene, confirming evolutionary affinity of the new species to the two morphologically similar taxa. The three sampled individuals from the two presently known populations of the new species cluster together in the phylogenetic analysis, separated from the other two closest taxa by two common base substitutions, confirming the recognition of this new species. © 2012 Magnolia Press. Source

Zhong X.-L.,South China Agricultural University | Zhong X.-L.,Nanjing University | Zhong X.-L.,CAS Nanjing Institute of Soil Science | Zhou S.-L.,Nanjing University | And 2 more authors.
Journal of Hazardous Materials | Year: 2011

Mobility and bioavailability of soil heavy metals strongly depend on their fractions. Secondary-phase fraction (SPF) of heavy metal, including acid-soluble, reducible and oxidizable fractions, is considered as direct and potential hazardous fraction to organisms. The ratio of SPF to the total concentration of heavy metal represents its bioavailability. In this study, 126 topsoil samples were collected in Kunshan, Jiangsu, China. Fraction concentrations of heavy metals, and their bioavailability and spatial distributions were determined, and relationships between their fractions and types of industry zones were analyzed. Results showed that Cd and Pb had the greatest SPFs among all metals (78.61% and 62.60%, respectively). Great SPFs of Cd and Pb were observed in the dyeing and paper-making industry zone, while great SPFs of Cr, Cu, Zn, Ni were in the smelting and plating industry zone. For most metals, fraction distributions were controlled by soil organic matter and clay contents. Spatial principal component analysis showed SPFs of heavy metals can be explained by two principle components (PCs). PC1 represented SPFs of Cd, Cr, Cu, Pb and Zn, while PC2 represented SPFs of Ni and Co. The spatial distributions of SPFs were influenced by geochemical character, industrial sewage irrigation and soil physico-chemical properties. © 2011 Elsevier B.V. Source

Xie Y.,Shandong University | Xu D.,Shandong University | Huang B.,Shandong Academy of Agricultural Sciences | Ma X.,Shandong Academy of Agricultural Sciences | And 5 more authors.
Journal of Medicinal Chemistry | Year: 2014

To discover group-1-specific neuraminidase (NA) inhibitors that are especially involved in combating the H5N1 virus, two series of oseltamivir derivatives were designed and synthesized by targeting the 150-cavity. Among these, compound 20l was the most potent N1-selective inhibitor, with IC50 values of 0.0019, 0.0038, and 0.0067 μM against NAs from three H5N1 viruses. These values are better than those of oseltamivir carboxylate. Compound 32 was another potent N1-selective inhibitor that exhibited a 12-fold increase in activity against the H274Y mutant relative to oseltamivir carboxylate. Molecular docking studies revealed that the 150-cavity was an auxiliary binding site that may contribute to the high selectivity of these compounds. The present work is a significant breakthrough in the discovery of potent group-1-specific neuraminidase inhibitors, which may be further investigated for the treatment of infection by the H5N1 virus. © 2014 American Chemical Society. Source

Tang Q.,CAS South China Sea Institute of Oceanology | Zheng C.,South China Agricultural University
Journal of Asian Earth Sciences | Year: 2013

We present a 3D S-velocity model for the crust and upper mantle of the South China Sea and the surrounding regions, constrained from the analysis of over 12,000 of fundamental Rayleigh wave dispersion curves between 10. s and 150. s periods. The lateral resolution was found to vary from 2° to 4° with the increasing period over the study region. A robust scheme of Debayle and Sambridge allowed us to conduct the tomographic inversion efficiently for massive datasets. Group velocity maps varying with period show lateral heterogeneities, well related to the geological and tectonic features in the study region. The 3D S-velocity model was constructed from the 1D structure inversion of the tomographic group velocity dispersion curves at each node. The obtained average crustal structure is similar to the PREM model, while the average mantle velocity is typically lower than the global average. The complicated 3D structures reveal three prominent features correlated with geological divisions: sea basin regions, island and arc regions, and continental regions. The derived crustal and lithospheric thicknesses range from ∼15 to >50. km and from ∼60 to >140. km, respectively, with the thinnest in the South China Sea, the thickest in eastern Tibet and the Yangtze Block, and the medium in the South China Fold Belt, Indochina, and island arc regions. Our results further confirm that (1) a Mesozoic subduction zone, which is interpreted as the tectonic weak zone during the Paleogene, exists along the South China margin; (2) the influence of the Indochina extrusion along the Red River Fault is limited for the South China Sea region; (3) there is a slab remnant of the proto-South China Sea beneath Borneo. New findings suggest that the Mesozoic subduction zone should be built into any evolution model for the region, as well as the other two major tectonic boundaries of the Red River Fault and proto-South China Sea subduction zone. © 2012 Elsevier Ltd. Source

Liang Z.,Shenzhen University | Zhu L.-X.,South China Agricultural University
Advanced Materials Research | Year: 2012

The current public transportation guidance models are static and based on travel times, travel distance and travel costs. However latest survey shows that travel time has become the key factor for passenger travel route selection in big cities. Dynamic public transportation guidance model based on travel time and waiting time was proposed and the effectiveness of this model is proved in this paper. To solve this model efficiently, this paper proposed the application of A* algorithm in dealing with this models using straight line distance between two bus stops in electronic maps as Priori knowledge. Finally, the developed model and algorithm were implemented with 50 random OD pairs based on Guangzhou's public transportation networks (containing 471 public transportation routes and 1040 stops) and Guangzhou's electronic map. Their computational performance was analyzed experimentally. The result indicates that the models and algorithm proposed in this paper are very efficient. The average computation time of the algorithm proposed in this paper is 0.154s and the average number of nodes selected of this algorithm is 194.2. Source

Situ H.,South China Agricultural University
Quantum Information Processing | Year: 2016

Nonlocality, one of the most remarkable aspects of quantum mechanics, is closely related to Bayesian game theory. Quantum mechanics can offer advantages to some Bayesian games, if the payoff functions are related to Bell inequalities in some way, most of these Bayesian games that have been discussed are common interest games. Recently, the first conflicting interest Bayesian game is proposed in Phys. Rev. Lett. 114, 020401 (2015). In the present paper, we present three new conflicting interest Bayesian games where quantum mechanics offers advantages. The first game is linked with Cereceda inequalities, the second game is linked with a generalized Bell inequality with three possible measurement outcomes, and the third game is linked with a generalized Bell inequality with three possible measurement settings. © 2015, Springer Science+Business Media New York. Source

Tian M.,South China Agricultural University
Journal of Cave and Karst Studies | Year: 2013

A new genus, Guiodytes gen. nov., and two new species, G. cavicola sp. nov. and G. bedosae sp. nov., of the ground beetle tribe Clivinini (Coleoptera: Carabidae) are described from two caves of Guangxi, southern China. Guiodytes gen. nov. is characterized. It is the first genus of troglobitic clivinines discovered in Asia, and its relationships with other clivinines remain unclear. Source

Liu T.,South China Agricultural University
Advanced Materials Research | Year: 2013

The aim of the investigation is to analyze the natural frequency of litchi tree. The litchi tree was simplified into a cantilever beam with a concentrated mass attached at the free end. Equivalent mass equation and stiffness equation were established to calculate the natural frequency. Effect of canopy mass, trunk length, bottom radius of trunk, and top radius of trunk to the natural frequency of litchi tree was analyzed. The analysis results showed that natural frequency decreases with canopy mass and trunk length, and increases with bottom radius and top radius of the trunk. And in a conventional trunk radius, length, and canopy mass range, the natural frequency in cycles of the litchi tree is between 0.5-5Hz. © (2013) Trans Tech Publications, Switzerland. Source

A new species of the genus Guiodytes Tian, 2013 is described from a limestone cave called Shuiku Dong in Huanjiang County of northernmost Guangxi, southern China. G. deharvengi n. sp. is the first depigmented species of Guiodytes. It is close to G. cavicola Tian, 2013, but easily recognized by its broader and yellowish brown body. In addition, new records for G. cavicola Tian, 2013 are provided from two caves in Du'an County of northern Guangxi, with description of the male genitalia. A key to all three known species and a distributional map of Guiodytes are also given. Copyright © 2014 Magnolia Press. Source

In order to elucidate the immune-protective mechanisms of inactivated Cryptocaryon irritans vaccine, different doses of C. irritans theronts were used to immunize orange-spotted grouper (Epinephelus coioides). We measured serum immobilization titer, blood leukocyte respiratory burst activity, serum alternative complement activity, and serum lysozyme activity weekly. In addition, the expression levels of immune-related genes such as interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), major histocompatibility complexes I and II (MHC I and II), and transforming growth factor-β1 (TGF-β1) were determined in spleen and gills. The results showed that the immobilization titer, respiratory burst activity, and alternative complement activity of immunized fish were significantly increased, and the levels of the last two immune parameters in the high-dose vaccine group were significantly higher than in the low-dose vaccine group. Serum lysozyme activity in the high-dose vaccine group was significantly higher than in the PBS control group. Vaccination also regulated host immune-related gene expression. For example, at 2- and 3- weeks post immunization, IL-1β expression in the high-dose vaccine group spleen was significantly increased. At 4-weeks post immunization, the fish were challenged with a lethal dose of parasite, and the survival rates of high-dose vaccine group, low-dose vaccine group, PBS control group, and adjuvant control group were 80%, 40%, 0%, and 10% respectively. These results demonstrate that inactivated C. irritans vaccination improves specific and nonspecific immune responses in fish, enhancing their anti-parasite ability. These effects are vaccine antigen dose-dependent. Copyright © 2013 Elsevier Ltd. All rights reserved. Source

Jeratthitikul E.,Kyoto University | Hara T.,Shinshu University | Yago M.,University of Tokyo | Itoh T.,Shinshu University | And 3 more authors.
Molecular Phylogenetics and Evolution | Year: 2013

The widespread lycaenid butterfly Tongeia fischeri is distributed from eastern Europe to northeastern Asia and represented by three geographically isolated populations in Japan. In order to clarify the phylogeographic history of the species, we used sequences of three mitochondrial (COI, Cyt b and ND5) and two nuclear (Rpl5 and Ldh) genes of 207 individuals collected from 55 sites throughout Japan and five sites on the Asian continent. Phylogenetic trees and the median-joining network revealed six evolutionary mitochondrial haplotype clades, which corresponded to the geographic distribution of the species. Common ancestors of Japanese T. fischeri might have come to Japan during the mid-Pleistocene by multiple dispersals of continental populations, probably via a land bridge or narrow channel between western Japan and the Korean Peninsula. The geographical patterns of variation of mitochondrial and nuclear markers are discordant in northeastern Kyushu, possibly as a result of introgressive hybridization during the ancient contact between the Kyushu and Shikoku populations in the last glacial maximum. The phylogeographic pattern of T. fischeri in Japan are probably related to the geological history, Pleistocene climatic oscillations and distribution of the host plant. © 2012 Elsevier Inc. Source

Li X.,South China University of Technology | Li X.,South China Agricultural University | Chen X.,South China University of Technology | Li Z.,South China University of Technology
Journal of Chemical and Engineering Data | Year: 2010

Activated carbon (AC) was modified by oxidation with nitric acid and microwave-assisted reduction. The textural properties and surface oxygen content as well as the surface acidities of the ACs studied were determined by nitrogen adsorption, X-ray photoelectron spectrometry, and Boehm titration. The adsorption isotherms of the water vapor were measured, and temperature- programmed desorption experiments were conducted to estimate the desorption activation energy, Ed, of water on the ACs. The results indicated that the oxidation increased the value of Ed and the adsorption capacity of water on AC in low relative humidity (RH) but decreased the adsorption capacity of water in high RH. The reduction decreased the value of Ed and the adsorption capacity of water on AC over the whole RH range. The modification of AC first by the oxidation treatment of nitric acid and then by microwave-assisted reduction treatment not only increased the adsorption capacity of water in a high RH but also greatly decreased the value of Ed. The microwave-assisted reduction of virgin or oxidized AC with hydrogen should yield a lower Ed and higher adsorption capacity of water in high RH than the reduction of that with nitrogen. © 2010 American Chemical Society. Source

Cuthbertson A.G.S.,UK Environment Agency | Qiu B.-L.,South China Agricultural University | Murchie A.K.,Agri Food and Biosciences Institute of Northern Ireland
Insects | Year: 2014

The increasing concern over the continued use of pesticides is pressurising apple growers to look for alternatives to chemical pest control. The re-discovery, and subsequent conservation, of the beneficial predatory mite, Anystis baccarum (Linnaeus) (Acari: Anystidae), in Bramley apple orchards in Northern Ireland offers a potential alternative control component for incorporation into integrated pest management strategies. Anystis baccarum readily feeds upon economically important invertebrate pest species including European fruit tree red spider mite, Panonychus ulmi (Koch) (Acari: Tetranychidae) and show a level of compatibility with chemical pesticides. Recent mis-identification by apple growers of this beneficial mite species had resulted in unnecessary pesticide applications being applied within Northern Irish apple orchards. However, dissemination of information to the apple growers and promotion of the benefits this mite offers in apple orchards has helped to conserve its populations. Apple growers, across the United Kingdom, must be encouraged to be aware of A. baccarum, and indeed all predatory fauna, within their orchards and seek to conserve populations. In doing so, it will ensure that the British apple market remains an environmentally sustainable production system. © 2014 by the authors; licensee MDPI, Basel, Switzerland. Source

Xue L.,South China Agricultural University
Scandinavian Journal of Forest Research | Year: 2014

Most traditional studies of mean tree mass (MTM)– density relationships focus on crowded stands, without considering stands characterized with canopy gaps. We developed a model to estimate MTM of closed and unclosed forest stands based on stand density index (SDI). Data were obtained from eight forest stands in China to test the generality of this model. MTM was accurately expressed in terms of SDI by combining the equations for SDI and Yoda's model, and exponents of the MTM–SDI relationship ranged from –2.23 to 1.93. Compared with density, SDI is a better predictor of MTM, regardless of the degree of canopy closure in the stands. © 2014, © 2014 Taylor & Francis. Source

Jin R.,South China University of Technology | Fan L.,South China Agricultural University | An X.,South China University of Technology
Chromatographia | Year: 2011

A new extraction technique, ionic liquid-assisted extraction (ILAE), has been developed. The ILAE process was further optimized by varying different parameters such as pretreatment time and temperature, ionic liquid/sample ratio, particle size and solvents. Under the optimum conditions, the extraction yield of ILAE was higher than that of Soxhlet extraction. The results of bioassay test showed that crude extract of ILAE was almost the same with that of Soxhlet extraction. The results in this study can serve as a reference for the ILAE of effective constituents in medicinal plants. © 2011 Springer-Verlag. Source

Li X.,South China University of Technology | Li X.,South China Agricultural University | Li Z.,South China University of Technology
Journal of Chemical and Engineering Data | Year: 2010

The textural properties and the surface acidities of four commercial activated carbons (ACs) were determined separately by nitrogen adsorption and Boehm titration. The adsorption isotherms of water vapor on the ACs were measured by the gravimetric method and fitted by the simplified version of the Do - Do (DD) model. The results indicated that all isotherms of water vapor on the ACs can be well-fitted by the simplified version of the DD model. The value of parameter n in the model increases with the pore size of the AC and is very close to 5 when the average pore diameter is between (1.96 and 2.8) nm. The order of parameter N0 is in good agreement with that of the total surface group concentrations. The parameter CμS is almost equal to the amount adsorbed of water on the AC at a relative humidity of 100 % or to the value of its total pore volume. The parameter Kμ depends on the pore size and decreases with increasing pore size. The value of parameter b depends on the combined contribution of the pore size and total surface group concentration of the AC and increases with the total surface group concentration and pore size. © 2010 American Chemical Society. Source

Chen J.,CAS South China Botanical Garden | Zhao J.,South China Agricultural University | Erickson D.L.,Smithsonian Institution | Xia N.,CAS South China Botanical Garden | Kress W.J.,Smithsonian Institution
Molecular Ecology Resources | Year: 2015

The genus Curcuma L. is commonly used as spices, medicines, dyes and ornamentals. Owing to its economic significance and lack of clear-cut morphological differences between species, this genus is an ideal case for developing DNA barcodes. In this study, four chloroplast DNA regions (matK, rbcL, trnH-psbA and trnL-F) and one nuclear region (ITS2) were generated for 44 Curcuma species and five species from closely related genera, represented by 96 samples. PCR amplification success rate, intra- and inter-specific genetic distance variation and the correct identification percentage were taken into account to assess candidate barcode regions. PCR and sequence success rate were high in matK (89.7%), rbcL (100%), trnH-psbA (100%), trnL-F (95.7%) and ITS2 (82.6%) regions. The results further showed that four candidate chloroplast barcoding regions (matK, rbcL, trnH-psbA and trnL-F) yield no barcode gaps, indicating that the genus Curcuma represents a challenging group for DNA barcoding. The ITS2 region presented large interspecific variation and provided the highest correct identification rates (46.7%) based on BLASTClust method among the five regions. However, the ITS2 only provided 7.9% based on NJ tree method. An increase in discriminatory power needs the development of more variable markers. © 2014 John Wiley & Sons Ltd. Source

Li T.,South China Agricultural University | Xiao N.,South China University of Technology
International Arab Journal of Information Technology | Year: 2015

In this paper, we use gaifman graph to describe the topological structure of the Quantified Boolean Formulae (QBF), we mainly study the formula family with the Small World (SW) network topology. We analyze the traditional Davis, Putnam, Logemann and Loveland (DPLL) solving algorithm for QBF, then we improve the DPLL algorithm and propose the solving algorithm framework based on Small World Optimization Search (SWOS) algorithm, we apply this SWOS algorithm to determine the order of the DPLL branch variable. Our result proves that SWOS algorithm has a certain degree of effectiveness to improve the solving efficiency. It is valuable as an incomplete solution algorithm for search-based solver. © 2015, Zarka Private Univ. All rights reserved. Source

Zhu G.,Zhejiang University | Jiang Y.,Zhejiang University | Huang W.,Zhejiang University | Zhang H.,Zhejiang University | And 2 more authors.
Chemical Communications | Year: 2013

We proposed a highly reproducible method that enables atomic resolution transmission electron microscopy investigations of the dynamics of nanoparticles in liquids. An ultrathin liquid layer was established as a result of formation of bubbles that was initiated and tuned by beam radiation. The migration, aggregation and rotation of palladium nanoparticles were observed. This journal is © The Royal Society of Chemistry 2013. Source

Hu Q.,South China Agricultural University
Journal of Mathematical Physics | Year: 2011

We first establish local well posedness for a weakly dissipative periodic 2-component Camassa-Holm system. We then present two global existence results for strong solutions to the equation. We finally obtain several blow-up results and the blow-up rate of strong solutions to the equation. © 2011 American Institute of Physics. Source

Zhang N.-Z.,Chinese Academy of Agricultural Sciences | Huang S.-Y.,Chinese Academy of Agricultural Sciences | Zhou D.-H.,Chinese Academy of Agricultural Sciences | Chen J.,Chinese Academy of Agricultural Sciences | And 6 more authors.
BMC Infectious Diseases | Year: 2013

Background: Toxoplasma gondii can infect almost all warm-blood animals including human beings. The plant-like calcium-dependent protein kinases (CDPKs) harbored by T. gondii are involved in gliding motility, cell invasion, egress and some other developmental processes, and so have been implicated as important virulence factors.Methods: In the present study, we constructed a DNA vaccine expressing T. gondii CDPK3 (TgCDPK3) and evaluated its protective efficacy against T. gondii infection in Kunming mice. The gene sequence encoding TgCDPK3 was inserted into the eukaryotic expression vector pVAX I, and mice were immunized with pVAX-CDPK3 intramuscularly.Results: The results showed that mice immunized with pVAX-CDPK3 developed a high level of specific antibodies and a strong lymphoproliferative response. The significantly increased levels of IFN-γ, IL-2, IL-12 (p70) and IL-23 and high ratio of IgG2a to IgG1 antibody titers indicated that a Th1 type response was elicited after immunization with pVAX-CDPK3. Furthermore, the percentage of CD4+ T cells in mice vaccinated with pVAX-CDPK3 was significantly increased. After lethal challenge with the tachyzoites of the virulent T. gondii RH strain, the mice immunized with pVAX-CDPK3 prolonged the survival time from 10 days to 24 days (13.5 ± 4.89) compared to untreated mice or those received PBS or pVAX I which died within 7 days (P < 0.05). In chronic infection model (10 cysts of the T. gondii PRU strain), the numbers of brain cysts of the mice immunized with pVAX-CDPK3 reduced significantly when compared with those in control groups (P < 0.05), and the rate of reduction could reach to about 50%.Conclusions: TgCDPK3 can generate protective immunity against acute and chronic T. gondii infection in Kunming mice and is a promising vaccine candidate for further development of an effective vaccine against T. gondii. © 2013 Zhang et al.; licensee BioMed Central Ltd. Source

Tang J.,Guangdong Academy of Agricultural Sciences | Yu X.,Purdue University | Luo N.,South China Agricultural University | Xiao F.,University of Idaho | And 2 more authors.
Plant, Cell and Environment | Year: 2013

Natural variation in salinity response, effects of population structure on growth and physiological traits and gene-trait association were examined in 56 global collections of diverse perennial ryegrass (Lolium perenne L.) accessions. Three population structure groups were identified with 66 simple sequence repeat markers, which on average accounted for 9 and 11% of phenotypic variation for the control and salinity treatment at 300mm NaCl. Group 1 (10 accessions) had greater plant height, leaf dry weight and water content, chlorophyll index, K+ concentration and K+/Na+ than group 2 (39 accessions) and group 3 (7 accessions) under salinity stress, while group 3 had higher Na+ than groups 1 and 2. Eighty-seven single nucleotide polymorphisms were detected from four partial candidate genes encoding aquaporin and Na+/H+ antiporter in both plasma and tonoplast membranes. Overall, rapid decay of linkage disequilibrium was observed within 500bp. Significant associations were found between the putative LpTIP1 and Na+ for the control and between the putative LpNHX1 and K+/Na+ under the control and salinity treatments after controlling population structure. These results indicate that population structure influenced phenotypic traits, and allelic variation in LpNHX1 may affect salinity tolerance of perennial ryegrass. Exploration of natural variation in salinity response of plants facilitates the analysis of gene and trait association. Three population structures were identified in 56 accessions of perennial ryegrass ( Lolium perenne L.) accounting for 11% of phenotypic trait variations under 300mM NaCl treatment. Significant associations were found between LpNHX1 and leaf K + / Na + under both control and salinity stress after controlling population structures. These results indicate allelic variation in LpNHX1 may affect salinity tolerance of perennial ryegrass. © 2013 John Wiley & Sons Ltd. Source

Nie P.-Y.,Guangdong University of Finance | Chen Y.-H.,South China Agricultural University
Energy Sources, Part B: Economics, Planning and Policy | Year: 2016

This research focuses on price discrimination policy in a duopoly market structure of firms purchasing energy from a monopolist supplier. The results indicate that the price discrimination of energy reduces social welfare and harms efficient firms, helping explain bans on price discrimination. Firms with lower efficiency benefit from price discrimination, while firms with higher efficiency suffer. Although the profits of efficient producers are reduced under price discrimination, the monopolist energy supplier is prone to price discrimination. The results from this research indicate that price discrimination for energy input is irrational. © 2016 Taylor & Francis Group, LLC. Source

Luo J.,South China University of Technology | Peng F.,South China University of Technology | Yu H.,South China University of Technology | Wang H.,South China University of Technology | Zheng W.,South China Agricultural University
ChemCatChem | Year: 2013

It was reported for the first time that carbon nanotubes (CNTs) as metal-free catalyst exhibited an excellent activity in the selective oxidation of ethylbenzene (EB) to acetophenone (AcPO) in the liquid-phase with oxygen as the oxidant. The reasonable mechanism responsible for the liquid-phase oxidation of EB on CNTs was proposed. The results demonstrated that the CNTs played an important role in the decomposition of 1-phenylethyl hydroperoxide (PEHP) and contributed to the production of AcPO, owing to π-π interactions between the radical species and peroxides and the graphene sheets of the CNTs. Surface carboxylic groups of the CNTs were unfavorable to EB oxidation. Adsorption energies of the radical species and peroxides on pristine and modified CNTs with carboxylic groups were calculated by DFT. These theoretical calculations were well consistent with the experimental results, and also supported the presented mechanistic pathway of EB oxidation on CNTs. This study not only presents a facile and effective alternative to cobalt-based catalysts for the selective oxidation of EB to AcPO but also gives new insight into the effect of surface structures on carbon-catalyzed reactions, and further pushes forward the research on carbon catalysis. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Xu D.,South China Agricultural University
Journal of Networks | Year: 2014

This article reports a Dynamic Routing Algorithm for Farmland Sensor Networks (DRA-FSN) based on channel quality control to improve energy efficiency, which combines the distance and communication characteristics of farmland wireless sensor network. The functional architecture of the DRA-FSN algorithm, routing establish the mechanisms, the communication transmission mechanism, the global routing beacon return mechanism, abnormal node handling mechanism and sensor networks timing control mechanisms were designed in detail in this article. This article also evaluates and simulated the performance of DRA-FSN algorithm in different conditions from energy efficiency, packet energy consumption and packet distribution balance by comparing DRA-FSN algorithm with DSDV, EAP algorithm. Simulations showed that the DRA-FSN was more energy efficient than EAP and DSDV, the DRA-FSN algorithm overcame the shortcoming that capacity and bandwidth of the routing table correspondingly increase as more and more nodes joining the network. It has better performance in scalability and network loading balance. © 2014 ACADEMY PUBLISHER. Source

Zhang W.,South China Agricultural University
DNA and cell biology | Year: 2012

This study was performed to identify and characterize the pig TDRP1 gene and to investigate its association with reproduction traits. The obtained pig TDRP1 cDNA (713 base pair [bp]) comprises a 561-bp open reading frame, which encodes a peptide of 187 amino acids. The identities of pig TDRP1 cDNA were 84.6%, 75.7%, and 77.4% with its counterparts in human, rat, and mice, respectively. Real-time polymerase chain reaction indicated that pig TDRP1 gene was highly expressed in pituitary of male and uterus of female animals. The pig TDRP1 gene contains three exons and two introns. A total of 13 single-nucleotide polymorphisms (SNPs) and 1 indel were identified in the screened partial genomic sequence, with most polymorphisms in introns. Allelic frequencies of five SNPs among eight pig breeds were further investigated, and it indicated that Landrace had the lowest genetic diversity. In Yorkshire, three SNPs (c.215+144T>C, c.215+249A>G, and c.215+672T>C) exhibited complete linkage disequilibrium in one haplotype block, and association analyses showed that all of them were significantly associated with number born alive of first parity (NBA1) (p<0.05). c.215+672T>C was also significantly associated with NBA6 (p<0.05). In addition, these three SNPs and two other ones (c.215+1001G>A and c.215+1026C>T) were associated with total born alive of second parity (TBA2) and TBA6 at the suggestive level (0.05 Source

Xu Y.,Jinan University | Deng H.-D.,South China Agricultural University
Optics Letters | Year: 2016

We study the electromagnetic wave propagating in coupled monolayer graphene waveguide arrays (CMGWAs). It is found that Anderson localization exists when the disorder in the coupling strength between adjacent waveguides is introduced. We find that changing the statistical parameters of the disorder coupling strength between waveguides can be used to tailor the properties of the Anderson localization modes in the strong coupling region which is beyond the coupled-mode theory. Benefiting from the electric tunable surface conductivity, we further demonstrate via the full vectorial simulation that the localization strength of the Anderson localized mode can be manipulated by changing the applied gate voltage on the CMGWAs. Our results might facilitate the manipulation of electromagnetic wave propagation in the coupled waveguide array system. © 2016 Optical Society of America. Source

Bi H.,University of Illinois at Urbana - Champaign | Wang H.,South China Agricultural University | Cronan J.E.,University of Illinois at Urbana - Champaign
Chemistry and Biology | Year: 2013

Summary In the classical anaerobic pathway of unsaturated fatty acid biosynthesis, that of Escherichia coli, the double bond is introduced into the growing acyl chain by the FabA dehydratase/isomerase. Another dehydratase, FabZ, functions in the chain elongation cycle. In contrast, Aerococcus viridans has only a single FabA/FabZ homolog we designate FabQ. FabQ can not only replace the function of E. coli FabZ in vivo, but it also catalyzes the isomerization required for unsaturated fatty acid biosynthesis. Most strikingly, FabQ in combination with E. coli FabB imparts the surprising ability to bypass reduction of the trans-2-acyl-ACP intermediates of classical fatty acid synthesis. FabQ allows elongation by progressive isomerization reactions to form the polyunsaturated fatty acid, 3-hydroxy-cis-5, 7-hexadecadienoic acid, both in vitro and in vivo. FabQ therefore provides a potential pathway for bacterial synthesis of polyunsaturated fatty acids. © 2013 Elsevier Ltd. Source

Weng J.,South China Agricultural University | Weng J.,Jinan University | Zhong J.,Jinan University
Optics Communications | Year: 2013

A numerical reconstruction technique employing the angular multiplexing and de-multiplexing by means of the Gabor wavelet transform (GWT) in digital holography is described. The single synthetic digital hologram of angular multiplexing is obtained by encoding the information corresponding to more than one carrier frequency, or by adding the rotated holograms recorded in turn during the dynamic course numerically. The de-multiplexing is performed by employing the GWT with multiple ridges and multiple peaks for the analysis to reconstruct each object wave front according to the respective rotated hologram. The results of the simulation and experiments show the feasibility and validity of the technique. © 2012 Elsevier B.V. Source

Liu M.,South China Agricultural University
Match | Year: 2010

The distance energy of a graph G is defined as the sum of the absolute values of the eigenvalues of the distance matrix of G. Two graphs with the same distance energy (resp. different distance matrix spectra) are called D-equienergetic (resp. non-D-cospectral). Recently, Indulal et. al. proved that there exists pairs of non-D-cospectral D-equienergetic graphs of order n when n ≡ 1(mod 3) or n ≡ 0(mod 6). In this paper, we prove that there exist pairs of non-D-cospectral D-equienergetic graphs of order n for every n ≥ 6. Source

Guo Z.-Z.,South China Agricultural University
Superlattices and Microstructures | Year: 2014

The lateral spin valve structures operated by the principle of spin- torque effect have shown great potentials for constructing the all- spin - logic. Like vertical spin valves, the problem of excessive spin-torque critical current also exists in lateral spin valves. Appropriate channel materials may reduce the spin-torque critical current, so finding the right channel material is a direction of many authors' efforts over years. In this paper, the four-component distributed spin-circuit model is used to calculate the spin-polarized current which is transported from the polarizer (fixed layer) to the detector (free layer). The effects of channel material parameters on the spin-torque critical current in the free layer of the lateral spin valve are studied numerically by using the Landau-Lifshitz-Gilbert-Slonczewski equation. Based on the numerical results, the problem of whether graphene is a suitable channel material is discussed. © 2014 Elsevier Ltd. All rights reserved. Source

Huang Q.,South China Agricultural University | Wong D.S.,City University of Hong Kong | Susilo W.,University of Wollongong
IEEE Transactions on Information Forensics and Security | Year: 2011

Designated confirmer signature (DCS) extends the undeniable signature so that a party called confirmer can also confirm/disavow nonself-authenticating signatures on the signer's behalf. Previous DCS schemes, however, can let a signer confirm a valid signature but not disavow an invalid one, while only a confirmer can. It remains open to construct a DCS which also allows the signer to disavow. In this work, we propose new security models for formalizing the signer's ability to disavow. We propose a new DCS scheme and prove its security without random oracles. The new DCS scheme is efficient and also convertible. A signature in this new DCS consists of only three bilinear group elements. This is much shorter than any of the existing schemes. In addition, the scheme can be extended to support multiple confirmers and threshold conversion. Adding a confirmer incurs the addition of only one group element in a signature. Furthermore, we propose an efficient construction of ambiguous optimistic fair exchange (AOFE) of digital signatures based on the new DCS scheme. A partial AOFE signature consists of three elements in an elliptic curve group and four in group ${\BBZ}-p$, and a full signature has only three group elements, which are shorter than those in Garay 's scheme (Crypto 1999) and Huang 's scheme (Asiacrypt 2008). © 2006 IEEE. Source

Huang Q.,South China Agricultural University | Wong D.S.,City University of Hong Kong | Susilo W.,University of Wollongong
Information Sciences | Year: 2011

Optimistic Fair Exchange (OFE) of digital signatures allows two parties to exchange their signatures in a fair manner so that a third party, called the arbitrator, gets involved only when there is a dispute. Previous work on OFE considers the two parties as individuals and there is no formal study on the scenario where the two parties are two groups of users. In this paper, we formalize this new variant and call it a Group-oriented Optimistic Fair Exchange (GOFE). GOFE allows two users from two different groups to exchange signatures on behalf of their groups in a fair and anonymous manner. We formalize the notion by providing the first set of security models for GOFE, and show that it is closely related to Ambiguous OFE (AOFE) proposed by Huang et al. in Asiacrypt 2008. In particular, we propose a generic transformation which converts a GOFE to an AOFE. We also give an efficient and concrete GOFE construction and prove its security under the security models we defined. The security of the scheme relies on the decision linear assumption and strong Diffie-Hellman assumption in the random oracle model. © 2011 Elsevier Inc. All rights reserved. Source

Liu M.,South China Agricultural University | Liu M.,South China Normal University | Liu B.,South China Normal University
Mathematical and Computer Modelling | Year: 2010

The Wiener index of a tree T obeys the relation W(T)=Σ en 1(e)·n 2(e), where n 1(e) and n 2(e) are the number of vertices adjacent to each of the two end vertices of the edge e, respectively, and where the summation goes over all edges of T. Lately, Nikolić, Trinajstić and Randić put forward a novel modification mW of the Wiener index, defined as mW(T)=Σ e(n 1(e)·n 2(e)) -1. Very recently, Gutman, Vukičević and Zerovnik extended the definitions of W(T) and mW(T) to be mWλ(T)=Σ e(n 1(e)·n 2(e)) λ, and they called mW the modified Wiener index of T, and mW λ(T) the variable Wiener index of T. Let δ(T) denote the maximum degree of T. Let T n denote the set of trees on n vertices, and T n c={T∈T nδ(T)=c}. In this paper, we determine the first two largest (resp. smallest) values of mW λ(T) for λ>0 (resp. λ<0) in T n c, where c≥n/2. And we identify the first two largest and first three smallest Wiener indices in T n c(c≥n/2), respectively. Moreover, the first two largest and first two smallest modified Wiener indices in T n c(c≥n/2) are also identified, respectively. © 2010 Elsevier Ltd. Source

Liu M.,South China Agricultural University
Match | Year: 2010

The greatest eigenvalue of a line distance matrix D, denoted by λ(D), is called the spectral radius of D. In this paper, we obtain some sharp upper and lower bounds for λ{D). Source

Liu M.,South China Agricultural University | Liu M.,South China Normal University | Liu B.,South China Normal University
Computers and Mathematics with Applications | Year: 2010

A graph is called a Laplacian integral graph if the spectrum of its Laplacian matrix consists of integers, and a graph G is said to be determined by its Laplacian spectrum if there does not exist other non-isomorphic graph H such that H and G share the same Laplacian spectrum. In this paper, we obtain a sharp upper bound for the algebraic connectivity of a graph, and identify all the Laplacian integral unicyclic, bicyclic graphs. Moreover, we show that all the Laplacian integral unicyclic, bicyclic graphs are determined by their Laplacian spectra. © 2010 Elsevier Ltd. All rights reserved. Source

Liu M.-H.,South China Agricultural University | Liu M.-H.,South China Normal University | Liu B.,South China Normal University
Match | Year: 2010

Gutman had determined the trees on n vertices with the smallest and the greatest hyper-Wiener index (i.e., the star and path). In this paper, we identify the second up to seventh smallest hyper-Wiener indices of trees on n ≥ 17 vertices and the second up to fifteenth greatest hyper-Wiener indices of trees on n ≥ 20 vertices. Source

Huang Q.,South China Agricultural University | Wong D.S.,City University of Hong Kong | Susilo W.,University of Wollongong
Information Sciences | Year: 2015

How to sign an electronic contract online between two parties (say Alice and Bob) in a fair manner is an interesting problem, and has been extensively studied for a long time. Optimistic Fair Exchange (OFE) is an efficient solution to it, in which a semi-trusted third party, named the arbitrator, is responsible for resolving any dispute that may arise during an exchange between Alice and Bob. Recently, several variants of OFE, such as Ambiguous OFE (AOFE) and Perfect AOFE (PAOFE), have been introduced to protect the privacy of Alice and Bob. These primitives prevent any outsider from telling which parties are involved in an exchange of digital signatures before the exchange completes. However, in PAOFE, AOFE and all the existing works on OFE, the arbitrator can always learn the signer's full signature at (or even before) the end of resolution, which is undesirable in some important applications, for example, signing a contract between two parties which do not want others to find out even when there is a dispute that needs resolution by the arbitrator. In this work, we introduce a new notion called Privacy-Preserving Optimistic Fair Exchange (P2OFE) for protecting the privacy of users, in which other than Alice and Bob, no one else including the arbitrator, can collect any evidence about an exchange between them even after the resolution of a dispute. We formally define P2OFE and present the corresponding security models and propose a concrete and efficient construction of P2OFE. We also discuss about several extensions about implementation. Our scheme is proved to be secure under the given security models based on the Strong Diffie-Helllman and Decision Linear assumptions without relying on the random oracle heuristic. © 2015 Elsevier Inc. All rights reserved. Source

Liu M.,South China Agricultural University
Match | Year: 2010

This paper presents a simple approach to order the first Zagreb indices of connected graphs. Moreover, by the application of this simple approach, we extend the known ordering of the first Zagreb indices for some class of connected graphs. Source

Huang Q.,South China Agricultural University | Huang Q.,City University of Hong Kong | Yang G.,National University of Singapore | Wong D.S.,City University of Hong Kong | Susilo W.,University of Wollongong
International Journal of Information Security | Year: 2011

Designated verifier signature (DVS) allows a signer to convince a designated verifier that a signature is generated by the signer without letting the verifier transfer the conviction to others, while the public can still tell that the signature must be generated by one of them. Strong DVS (SDVS) strengthens the latter part by restricting the public from telling whether the signature is generated by one of them or by someone else. In this paper, we propose two new SDVS schemes. Compared with existing SDVS schemes, the first new scheme has almost the same signature size and meanwhile, is proven secure in the standard model, while the existing ones are secure in the random oracle model. It has tight security reduction to the DDH assumption and the security of the underlying pseudorandom functions. Our second new scheme is the first SDVS supporting non-delegatability, the notion of which was introduced by Lipmaa, Wang and Bao in the context of DVS in ICALP 2005. The scheme is efficient and is provably secure in the random oracle model based on the discrete logarithm assumption and Gap Diffie-Hellman assumption. © 2011 Springer-Verlag. Source

Li J.-M.,Sun Yat Sen University | Zhao M.-X.,Sun Yat Sen University | Su H.,Sun Yat Sen University | Wang Y.-Y.,Sun Yat Sen University | And 4 more authors.
Biomaterials | Year: 2011

The functional quantum dots (QDs) were specifically designed to overcome barriers in siRNA delivery such as siRNA protection, cellular penetration, endosomal release, carrier unpacking, intracellular transport and gene silencing. In this paper, two l-arginine-functional-modifi{ligature}ed CdSe/ZnSe QDs were synthesized as siRNA carriers to silence HPV18 E6 gene in HeLa cells. Using such constructs, these QDs showed significantly low cellular cytotoxicity and good siRNA protection. Flow cytometric and confocal microscopic analyses confirmed that the QDs delivered siRNA into HeLa cells efficiently. Importantly, superior gene silencing efficiency was achieved as evaluated by Reverse Transcription-PCR (RT-PCR) and Western blotting and HeLa cells growth was inhibited in xCELLigence installation analysis and MTT assay when treated with QD-siRNA complexes. Interestingly, the QDs coated with β-CD- l-Arg showed optimized property compared with those coated with l-Arg. Furthermore, these QDs complexes could also be used as nanocrystal probing agents, allowing real-time tracking and localization of QDs during delivery and transfection. The properties and capabilities of these QDs showed that amino acid-modifi{ligature}ed QDs could be used as useful siRNA carriers to effectively silence a target gene as well as fluorescence probes to analyze intracellular imaging in vivo. © 2011 Elsevier Ltd. Source

Xu C.,Sun Yat Sen University | Xu C.,South China Agricultural University | Chen Z.,Sun Yat Sen University | Chen D.,Sun Yat Sen University | And 2 more authors.
Applied Physics Letters | Year: 2010

A controllable pump-pulse-number magneto-optical Kerr technique combined with an initializing field scanning approach is developed to eliminate and identify memory and accumulation effects, respectively, from external field history and multiple pulse excitations. A series of anomalous loops of GdFeCo films are measured for different amount of pump pulses using this technique, revealing that serious memory and accumulation effects exist in continuous-pulse-pumped anomalous hysteresis loops which show illusory information of hot coercivity and degree of magnetization reversal. Single-pulse-induced anomalous loop reveals that the hot coercivity shown by continuous-pulse-pumped anomalous loops is not the minimum external field that drives real magneto-optical recording. © 2010 American Institute of Physics. Source

Chen L.,Nara Institute of Science and Technology | Chen L.,South China Agricultural University | Shimamoto K.,Nara Institute of Science and Technology
Journal of General Plant Pathology | Year: 2011

Molecular chaperones and co-chaperones are proteins that aid in the folding and assembly of other macromolecular structures or complexes. Although growing evidence suggests that molecular chaperones and co-chaperones play critical roles in plant innate immunity, the molecular mechanism of how these proteins contribute to defense signaling remains largely unknown. In this review, we highlight the cytoplasmic chaperones, endoplasmic reticulum (ER) resident lectin chaperones, and enzymes that have been identified from genetic and "omic" approaches and shown to be involved in plant-microbe interactions. We also discuss the roles of molecular chaperones in plant innate immunity and emerging mechanisms underlying the biogenesis of plant pathogen-associated molecular pattern receptors in the ER. © 2010 The Phytopathological Society of Japan and Springer. Source

Weng J.,South China Agricultural University | Weng J.,Jinan University | Zhong J.,Jinan University | Hu C.,Jinan University
Applied Optics | Year: 2010

The main factor that limits the quality of an image reconstructed by the process of spatial filtering in digital holographic microscopy is discussed. A spatial filter determined by the distribution of the spectrum of the virtual image is designed automatically for real time dynamic analysis of a micro-object, and an optimal reconstructed phase image can be obtained. An experiment of a holographic image with an onion specimen is presented to prove the validity of this approach. Comparing the numerical reconstruction of the hologram by employing different spatial filters with the automatic spatial filtering shows the superiority of the automatic spatial filtering method, and it is suitable for dynamic and automatic analysis. © 2010 Optical Society of America. Source

Nibau C.,University of Massachusetts Amherst | Nibau C.,Aberystwyth University | Tao L.,University of Massachusetts Amherst | Tao L.,South China Agricultural University | And 4 more authors.
Journal of Experimental Botany | Year: 2013

Rac-like GTPases or Rho-related GTPases from plants (RAC/ROPs) are important components of hormone signalling pathways in plants. Based on phylogeny, several groups can be distinguished, and the underlying premise is that members of different groups perform distinct functions in the plant. AtRAC7/ROP9 is phylogenetically unique among 11 Arabidopsis RAC/ROPs, and here it was shown that it functions as a modulator of auxin and abscisic acid (ABA) signalling, a dual role not previously assigned to these small GTPases. Plants with reduced levels of AtRAC7/ROP9 had increased sensitivity to auxin and were less sensitive to ABA. On the other hand, overexpressing AtRAC7/ROP9 activated ABA-induced gene expression but repressed auxin-induced gene expression. In addition, both hormones regulated the activity of the AtRAC7/ROP9 promoter, suggesting a feedback mechanism to modulate the signalling output from the AtRAC7/ROP9-controlled molecular switch. High levels of AtRAC7/ROP9 were detected specifically in embryos and lateral roots, underscoring the important role of this protein during embryo development and lateral root formation. These results place AtRAC7/ROP9 as an important signal transducer in recently described pathways that integrate auxin and ABA signalling in the plant. © The Author [2013]. Source

Zhang W.,CAS Guangzhou Institute of Geochemistry | Zhang W.,University of Chinese Academy of Sciences | Li X.,South China Agricultural University | Liu T.,Guangdong Institute of Eco environmental and Soil Sciences | Li F.,Guangdong Institute of Eco environmental and Soil Sciences
Journal of Soils and Sediments | Year: 2012

Purpose: Fe(III) has been reported as a strictly competitive electron acceptor with respect to other substrate reductions by dissimilatory Fe(III)-reducing bacteria (DIRB). However, the effect of Fe(III) oxides on the substrate reduction by other microorganisms remain unknown. The aims of this study were to investigate the effects of iron oxides on the nitrate reduction and current generation by Bacillus sp., in which the nitrate and carbon anodes served as soluble and insoluble electron acceptors, respectively. Materials and methods: Microbial nitrate reduction by Bacillus sp. were conducted in batch cultures in the absence or presence of four chemically synthesized iron(III) oxyhydroxides [i. e., α-FeOOH, γ-FeOOH, α-Fe2O3, and γ-Fe2O3]. Anaerobic techniques were used throughout all the experiments. NO3-/NO2- was determined by ion chromatography, and NH4+ was measured by spectrophotometry at 420 nm after a color reaction with Nessler's reagent. For total Fe(II) determination, samples were extracted using 0. 5 M HCl and tested by spectrophotometry at 510 nm, and Fe(II) analyses in NO3- containing samples were performed using a sequential extraction technique. Current generation was tested using a bioelectrochemical reactor that consisted of two identical chambers separated by a cation exchange membrane. Results and discussion: The results showed that four iron oxides markedly enhanced the nitrate reduction and current generation by Bacillus sp. Nitrate reduction by the Fe(II) on the oxide surface was proven to take place, but with lower reduction rate than the direct microbial nitrate reduction by Bacillus sp. Al2O3 and TiO2, as control without Fe(II) formation, also enhanced the nitrate reduction and current generation. It was proposed that the electron may be transferred from Bacillus sp. to conduction band of iron oxides to the nitrate or anode, according to their redox potential ranking as outer membrane enzyme of microorganisms < conduction band of iron oxides < electron acceptors. Conclusions: This study demonstrated that the presence of iron oxides can obviously enhance both the nitrate reduction and current generation by Bacillus sp., which was in contrast to the previous report with respect to the inhibition effect of Fe(III) on substrate reduction by DIRB. With respect to the semiconductive properties of iron oxides, their roles during the nitrate reduction and current generation were speculated as a conduction band of iron oxides mediating the electron transfer from Bacillus sp. to the nitrate and anode. © 2011 Springer-Verlag. Source

Xu W.,Chinese University of Hong Kong | Xu W.,CAS Nanjing Institute of Soil Science | Jia L.,Chinese University of Hong Kong | Jia L.,Inner Mongolia Agricultural University | And 5 more authors.
New Phytologist | Year: 2013

Maintenance of root growth is essential for plant adaptation to soil drying. Here, we tested the hypothesis that auxin transport is involved in mediating ABA's modulation by activating proton secretion in the root tip to maintain root growth under moderate water stress. Rice and Arabidopsis plants were raised under a hydroponic system and subjected to moderate water stress (-0.47 MPa) with polyethylene glycol (PEG). ABA accumulation, auxin transport and plasma membrane H+-ATPase activity at the root tip were monitored in addition to the primary root elongation and root hair density. We found that moderate water stress increases ABA accumulation and auxin transport in the root apex. Additionally, ABA modulation is involved in the regulation of auxin transport in the root tip. The transported auxin activates the plasma membrane H+-ATPase to release more protons along the root tip in its adaption to moderate water stress. The proton secretion in the root tip is essential in maintaining or promoting primary root elongation and root hair development under moderate water stress. These results suggest that ABA accumulation modulates auxin transport in the root tip, which enhances proton secretion for maintaining root growth under moderate water stress. © 2012 New Phytologist Trust. Source

Ouyang Y.,U.S. Department of Agriculture | Zhang J.-E.,South China Agricultural University
Water, Air, and Soil Pollution | Year: 2012

Of all groundwater pollution sources, septic systems are the second largest source of groundwater nitrate contamination in USA. This study investigated shallow groundwater (SGW) nutrient dynamics in septic areas at the northern part of the Lower St. Johns River Basin, Florida, USA. Thirty-five SGW-monitoring wells, located at nine different urban areas served by septic systems, were used to collect the SGW samples seasonally and/or biweekly for a duration of 3 years from 2003 to 2006. Analytical results showed that there were 16 wells with nitrate concentrations exceeding the US Environmental Protection Agency's drinking water limit (10 mg L -1). There also were 11 and 14 wells with total Kjeldahl nitrogen (TKN) and total phosphorus (TP) concentrations, respectively, exceeding the ambient water quality criteria (0.9 mg L -1 for TKN and 0.04 mg L -1 for TP) recommended for rivers and streams in nutrient Ecoregion XII (Southeast USA). In general, site variations are much greater than seasonal variations in SGW nutrient concentrations. A negative correlation existed between nitrate/nitrite-nitrogen (NO x-N) and TKN as well as between NO x-N and ammonium (NH + 4), whereas a positive correlation occurred between TKN and NH + 4. Furthermore, a positive correlation was found between reduction and oxidation (redox) potential and water level, while no correlation was observed between potassium concentration and redox potential. This study demonstrates a need to investigate the potential adverse impacts of SGW nutrients from the septic areas upon the deeper groundwater quality due to the nutrient penetration and upon the surface water quality due to the nutrient discharge. © Springer Science+Business Media B.V. (outside the USA) 2012. Source

Zhuang L.,Guangdong Institute of Eco environmental and Soil Sciences | Zhou S.,Guangdong Institute of Eco environmental and Soil Sciences | Li Y.,South China Agricultural University | Liu T.,Guangdong Institute of Eco environmental and Soil Sciences | Huang D.,Guangdong Institute of Eco environmental and Soil Sciences
Journal of Power Sources | Year: 2010

This study reports that Fenton's reaction is capable of facilitating cathodic reaction and thus increasing the current output in microbial fuel cells (MFCs). The hydroxyl radicals ({radical dot}OH) produced via Fenton's reaction are demonstrated to be vital to the enhancement of electricity generation in MFCs. In a two-chamber MFC employing expanded polytetrafluoroethylene (e-PTFE) laminated cloth as a separator, the power output is enhanced approximately four times with Fenton's reaction. However, the enhancement lasts only a short time period due to the rapid consumption of Fenton's reagents. To overcome this problem, a Fe@Fe2O3/carbon felt (CF) composite cathode is made, which results in a greater and, more importantly, sustainable power output. In the composite cathode, Fe@Fe2O3 functions as a controllably releasing Fenton iron reagent and CF functions as an air-fed cathode to electro-generate H2O2. This newly developed MFC with a Fenton system can ensure a continuous high power output, and also provides a potential solution to the simultaneous electricity generation and degradation of recalcitrant contaminants. © 2009 Elsevier B.V. All rights reserved. Source

Yang Y.,Jinan University | Cui J.,Jinan University | Zheng M.,South China Agricultural University | Hu C.,Jinan University | And 4 more authors.
Chemical Communications | Year: 2012

Highly amino-functionalized fluorescent carbon nanoparticles (CNPs) were fabricated by hydrothermal carbonization of chitosan at a mild temperature. They were applied to bioimaging of human lung adenocarcinoma A549 cells, showing low cytotoxicity and excellent biocompatibility. Source

Cai K.,South China Agricultural University
Yi Qi Yi Biao Xue Bao/Chinese Journal of Scientific Instrument | Year: 2012

According to the local sparseness of maternal ECG (electrocardiogram) and fetal ECG signals, a new semi-blind source separation method is proposed to extract fetal ECG from the mixed abdominal observations. The first step of the method is to search the local sparse segment in the abdominal observations. Then, the method converts the sparse segment into the Wigner-Ville time-frequency domain, and obtains the auto-terms of the source signals and the cross-terms between them, and constructs the objective function to extract fetal electrocardiogram. The method introduces the cross-terms of spatial Wigner-Ville distributions, which are thought to be useless and must be removed by kernel functions before further processing, to the contrast function for fetal ECG extractions. Thus, the proposed method is different from traditional blind source separation method in Wigner-Ville time-frequency domain. Simulation experiment results depict that the performance of the algorithm is much close to that of traditional methods. The similarity coefficient between the results obtained using the proposed method and FastICA method is 0.9533, and it is up to 0.9708 between the results obtained using the proposed method and traditional BSS method in Wigner-Ville time-frequency domain. Source

Li J.,University of Macau | Zhang J.,Guangzhou Institute of Landscape Gardening | Lu Y.,South China Agricultural University | Chen Y.,University of Macau | And 2 more authors.
Environmental Monitoring and Assessment | Year: 2012

The total petroleum hydrocarbons (TPH) pollution in regional agricultural soils was investigated. Seventy soil samples collected from surface layers (0-20 cm) and horizons of five selected pedons in the vicinity of a petrochemical complex in Guangzhou, China were analyzed, and the vertical variation and spatial variability of TPH were evaluated. The TPH concentration in top soils around the petrochemical complex ranged from 1,179.3 to 6,354.9 mg kg- 1, with the average of 2,676.6 mg kg- 1. Furthermore, significant differences between land-use types showed that the TPH concentration in top soils was strongly influenced by accidental spills. Both the TPH trends in pedons and the identified hot-spot areas also showed that the accidental explosions or burning accidents were mainly responsible for the pollution. The results reported here suggest that the regular monitoring and inspection shall be conducted for safety and to avoid or minimize the accidents, and the effective measures should be taken to remediate the contaminated areas and to assure that the important industrialization of Guangzhou area would not mean human health risks near the petrochemical complex. © 2011 Springer Science+Business Media B.V. Source

Wang C.,Institute of Molecular and Cell Biology | Yan C.,South-Central University for Nationalities | Fuqua C.,Indiana University Bloomington | Zhang L.-H.,South China Agricultural University
Journal of Bacteriology | Year: 2014

Quorum sensing (QS) is a widespread mechanism of bacterial communication in which individual cells produce and respond to small chemical signals. In Agrobacterium tumefaciens, an acylhomoserine lactone-dependent QS mechanism is known to regulate the replication and conjugation of the tumor-inducing (Ti) plasmid. Most of the QS regulatory proteins are encoded within the Ti plasmid. Among them, TraI is the LuxI-type enzyme synthesizing the QS signal N-3-oxooctanoyl-L-homoserine lactone (3OC8HSL), TraR is the LuxR-type transcriptional factor that recognizes 3OC8HSL, and TraM is an antiactivator that antagonizes TraR. Recently, we identified a TraM homolog encoded by the traM2 gene in the chromosomal background of A. tumefaciens A6. In this study, we further identified additional homologs (TraI2 and TraR2) of TraI and TraR in this strain. We showed that similar to TraI, TraI2 could predominantly synthesize the QS signal 3OC8HSL. We also showed that TraR2 could recognize 3OC8HSL and activate the tra box-containing promoters as efficiently as TraR. Further analysis showed that traM2, traI2, and traR2 are physically linked on a mobile genetic element that is not related to the Ti plasmid. These findings indicate that A. tumefaciens A6 carries a second QS system that may play a redundant role in the regulation of the replication and conjugation of the Ti plasmid. © 2014, American Society for Microbiology. Source

Liang T.,South China Agricultural University
Nan fang yi ke da xue xue bao = Journal of Southern Medical University | Year: 2013

To observe the behavioral changes of rats after subchronic exposure to di-(2-ethyl hexyl) phthalate (DEHP). Twenty-four healthy male SD rats were randomized equally into 4 groups, namely the solvent control group (sesame oil) and 3 DEHP groups with daily intragastric administration of DEHP at the doses of 150, 450, and 1350 mg/kg for 28 days. The neurobehavioral changes of rats were evaluated by open-field test (OFT) and elevated plus-maze test (EPM), and the body weight and organ coefficients were measured. The rats showed no significant differences in the performance in OFT or EPM before DEHP exposure. The body weight of the rats increased with the prolonged DEHP exposure, but no significant differences were found between the treatment groups and the control group (P>0.05). From the third week of exposure, the weekly food consumption and the food utilization rate showed significant differences between the treatment groups and the control group (P<0.05 and PP<0.01), and the liver and testis coefficients, but not the kidney coefficient, also differed significantly (PP<0.01, PP<0.01, and P>0.05). In OFT, the total distance of movement was the longest in high dose treatment group (PP<0.05 vs control group), and the durations of stay in the central area, but not the number of times of entry, differed significantly between the 3 treatment groups and the control group (PP<0.05 and P>0.05). In EPM test, however, the performances of the rats was all similar between the 4 groups (P>0.05). DEHP can affect the locomotor activity and exploratory behavior of rats after short-term exposure, suggesting its possible hazard in human being. Source

Wu Y.L.,Guangdong Academy of Agricultural Sciences | Yi G.J.,Guangdong Academy of Agricultural Sciences | Peng X.X.,South China Agricultural University
European Journal of Plant Pathology | Year: 2010

In order to accelerate breeding and selection for disease resistance to Fusarium wilt, it is important to develop bioassays which can differentiate between resistant and susceptible cultivars efficiently. Currently, the most commonly used early bioassay for screening Musa genotypes against Fusarium oxysporum f. sp. cubense (Foc) is a pot system, followed by a hydroponic system. This paper investigated the utility of in vitro inoculation of rooted banana plantlets grown on modified medium as a reliable and rapid bioassay for resistance to Foc. Using a scale of 0 to 6 for disease severity measurement, the mean final disease severities of cultivars expressing different levels of disease reaction were significantly different (P ≤ 0.05). Twenty-four days after inoculation with Foc tropical race 4 at 106 conidia ml-1, the plantlets of two susceptible cultivars had higher final disease severities than that of four resistant cultivars. Compared with 'Guangfen No.1', 'Brazil Xiangjiao' is highly susceptible to tropical race 4 and its mean final disease severity was the highest (5.27). The plantlets of moderately resistant cultivar 'Formosana' had a mean final disease severity (3.53) lower than that of 'Guangfen No.1' (4.33) but higher than that of resistant cultivars: 'Nongke No.1', GCTCV-119, and 'Dongguan Dajiao' (1.87, 1.73, and1.53, respectively). Promising resistant clones acquired through non-conventional breeding techniques such as in vitro selection, genetic transformation, and protoplast fusion could be screened by the in vitro bioassay directly. Since there is no acclimatization stage for plantlets used in the bioassay, it helps to improve banana breeding efficiency. © 2010 KNPV. Source

Liu C.-G.,Guangdong Academy of Agricultural Sciences | Zhang G.-Q.,South China Agricultural University
Acta Agronomica Sinica | Year: 2010

The genetic diversity of 95 major commercial inbred rice cultivars (Oryza sativa L. subsp. indica) released in South China from 1949 to 2005 were evaluated using 300 simple sequence repeat (SSR) markers distributing evenly on the whole rice genome. A total of 236 polymorphic loci were detected with 776 alleles. The number of allele per locus ranged from 2 to 12 with an average of 3.29. Only 2-4 alleles were found at 206 loci, which accounted for 87.3%. The average polymorphism information content (PIC) value of polymorphic loci was 0.42, which varied with chromosomes. Chromosome 10 had the greatest values in allele number per locus and PIC, and chromosome 5 had the lowest values. The allele number per locus showed an increase trend in the cultivars released from the 1950s to the 1970s and declined afterwards. Analysis of molecular variance (AMOVA) disclosed the significant genetic variation (P < 0.001) among cultivars from different decades, although it only explained 3.77% of the total genetic variation. The genetic distance among cultivars was decreased from the 1950s to the 2000s. According to clustering analysis with COMPLETE method, the 95 cultivars were grouped into 5 clusters at genetic similarity coefficient of 0.685, and several core parents were found in the cultivars released in each decade. The results indicate that the genetic diversity of indica rice cultivars in South China is in a low level and even narrowing after the 1970s. Thus, the genetic basis of indica rice cultivars should be broadened through incorporating new variability into existing rice germplasm in breeding programs. © 2010 Crop Science Society of China and Institute of Crop Sciences, Chinese Academy of Agricultural Sciences. Source

Tao Y.,South China Agricultural University
Advanced Materials Research | Year: 2011

In order to explore good teaching methods, the traditional teaching model and online teaching mode were compared and their own characteristics were analyzed. The results showed that two modes should be combined in order to better adapt to the current development of education rather than be not a single. Engineering drawing is a skill required of the basic course for engineering students. For many years, however, the blackboard, wall charts, models and other traditional teaching skills are very limited. With the rapid development of the electronics, information and communication technology, the online counseling system should be established without delay. Teachers and students, students and students can communicate well in the traditional teaching mode. Teachers can answer questions in time, however, the efficiency of class is low, and students cannot easily understand. Multimedia Network Teaching can improve teaching efficiency and enhance student interest in learning, which is important to the students' spatial imagination. At the beginning, there are still something unsatisfactory. Source

Majerczyk C.,University of Washington | Schneider E.,University of Washington | Greenberg E.P.,University of Washington | Greenberg E.P.,South China Agricultural University
eLife | Year: 2016

Burkholderia thailandensis uses acyl-homoserine lactone-mediated quorum sensing systems to regulate hundreds of genes. Here we show that cell-cell contact-dependent type VI secretion (T6S) toxin-immunity systems are among those activated by quorum sensing in B. thailandensis. We also demonstrate that T6S is required to constrain proliferation of quorum sensing mutants in colony cocultures of a BtaR1 quorum-sensing signal receptor mutant and its parent. However, the BtaR1 mutant is not constrained by and outcompetes its parent in broth coculture, presumably because no cell contact occurs and there is a metabolic cost associated with quorum sensing gene activation. The increased fitness of the wild type over the BtaR1 mutant during agar surface growth is dependent on an intact T6SS-1 apparatus. Thus, quorum sensing activates B. thailandensis T6SS-1 growth inhibition and this control serves to police and constrain quorum-sensing mutants. This work defines a novel role for T6SSs in intraspecies mutant control. © Majerczyk et al. Source

Liu B.,Henan Institute of Science and Technology | Zhu X.,South China Agricultural University | Zeng J.,Henan Institute of Science and Technology | Zhao J.,University of New South Wales
Food Research International | Year: 2013

Naringin dihydrochalcone (naringin DC) is an intense sweetener and a strong antioxidant with potential applications in many food and pharmaceutical products. However, its low water solubility impedes the realization of these applications. This study investigated the feasibility of using hydroxypropyl-β-cyclodextrin (HP-β-CD) to form a supramolecular inclusion complex with naringin DC to improve its solubility. The inclusion complex was prepared by stirring an equal molar solution of naringin DC and HP-β-CD at 30°C for 24h, followed by freeze-drying. The resultant complex was characterized by ultraviolet-visible spectroscopy (UV), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), X-ray diffractometry (XRD) and proton nuclear magnetic resonance spectroscopy (1H-NMR) to determine its spectral, phase transitional and morphological properties and to elucidate its conformational structure. Results showed clearly the formation of a supramolecular complex in which the guest molecule, naringin DC, was entrapped inside the cavity of the host, HP-β-CD. The close association between naringin DC and HP-β-CD resulted in changes in some of the characteristic spectral, phase transitional and morphological properties of naringin DC. Furthermore, 1H-NMR analyses demonstrated that it was the B ring of naringin DC that was inserted into the HP-β-CD cavity to form the supramolecular complex. © 2013 Elsevier Ltd. Source

Xu Z.,South China Agricultural University | Olmi M.,University of Tuscia | He J.,Zhejiang University
Oriental Insects | Year: 2010

Two new species, Anteon tenuitarse and A. pilosum (Dryinidae: Anteoninae) from Hainan and Zhejiang Provinces, and from Hainan and Ningxia Hui Nationality Autonomous Region of China, respectively are described. Keys for differentiating these given. Types deposited with the College of Nature Resources and Environment, South China Agricultural University, Guangzhou, P. R. China. Source

Sun Y.,University of Electronic Science and Technology of China | Xu C.,University of Electronic Science and Technology of China | Yu Y.,University of Electronic Science and Technology of China | Yang B.,South China Agricultural University
Computer Communications | Year: 2011

A proxy multi-signature scheme permits two or more original singers to delegate their signing powers to the same proxy signer. Recently, Liu et al. proposed the first proxy multi-signature that be proven secure in the standard model [Liu et al. (2008) [20]], which can be viewed as a two-level hierarchical signature due to Waters. However, because of the direct employment of Waters' signature, their scheme needs a relatively large number of public parameters and is not tightly reduced to the security assumption. In this paper, inspired by Boneh, Boyen's technique and Waters' technique, we propose a new proxy multi-signature scheme without random oracles, whose unforgeability can be tightly reduced to the CDH assumption in bilinear groups. The new scheme can be regarded as an improvement to overcome the weaknesses of Liu et al.'s scheme. Compared with Liu et al.'s scheme, the improvement has three merits, tighter security reduction, shorter system parameters and higher efficiency. © 2010 Elsevier B.V. All rights reserved. Source

Wu S.M.,South China Agricultural University
The Journal of parasitology | Year: 2011

In the present investigation, the seroprevalence of Toxoplasma gondii antibodies in 455 Tibetan sheep in Tibet, China, was examined using an indirect hemagglutination test. Of these, 26 (5.7%) Tibetan sheep were seropositive at the cut-off of 1:64 serum dilution. The seroprevalence ranged from 2.2% to 8.9% among Tibetan sheep of <1-yr-old, 1-3-yr-old, and >3-yr-old, but the differences among the age groups were not significant (P > 0.05). The prevalence in male Tibetan sheep (2.8%) was lower than that in female Tibetan sheep (6.6%), but the difference was not statistically significant (P > 0.05). The results of this survey indicated the presence of T. gondii infection in Tibetan sheep, which may cause economic losses to the local livestock industry and which poses a potential threat to human health in this area. Source

Ma Y.,South China Agricultural University | Lin C.,University of Southern Queensland
Journal of Hazardous Materials | Year: 2012

Chemical, XRD, SEM, RS, FTIR and XPS techniques were used to investigate arsenate immobilization associated with microbial Fe 2+ oxidation in a complex acid sulfate water system consisting of a modified 9K solution (pH 2.0) plus As, Cu, Cd, Pb, Zn and Mn. At a 1:12.5:70 molar ratio of As:Fe:S, schweretmannite formation was impeded. This was in contrast with the predominant presence of schwertmannite when the heavy metals were absent, suggesting that a schwertmannite binding model is not valid for explaining arsenate immobilization in the complex system. In this study, arsenate was initially immobilized through co-precipitation with non-Fe metals and phosphate. Subsequently when sufficient Fe 3+ was produced from Fe 2+ oxidation, formation of a mixed iron, arsenate and phosphate phase predominated. The last stage involved surface complexation of arsenate species. Pb appeared to play an insignificant role in arsenate immobilization due to its strong affinity for sulfate to form anglesite. Phosphate strongly competed with arsenate for the available binding sites. However, As exhibited an increased capacity to compete with P and S for available binding sites from the co-precipitation to surface complexation stage. Adsorbed As tended to be in HAsO 4 2- form. The scavenged arsenate species was relatively stable after 2464-h aging. © 2012 Elsevier B.V.. Source

Liu F.,Sun Yat Sen University | Tang Y.,Sun Yat Sen University | Du R.,Sun Yat Sen University | Yang H.,Sun Yat Sen University | And 2 more authors.
Plant and Soil | Year: 2010

Positive root response to metals may enhance metal accumulation for greater requirement in hyperaccumulators. The effects of spatially heterogeneous Zn/Cd addition on root allocation, metal accumulation, and growth of the Zn/Cd hyperaccumulator Sedum alfredii were assessed in a pot experiment. Young shoots of S. alfredii were grown with or without supplied Zn/Cd. Two concentrations were used of each metal, and each metal concentration had one homogeneous and two heterogeneous treatments. Growth increased by 1. 6-3. 2 times with the increasing overall dose of Zn/Cd addition, and shoot biomass was positively correlated with shoot Zn/Cd concentration (P < 0. 001). In all heterogeneous treatments, the plants consistently allocated approximately 90% of root biomass to the metal-enriched patches, and shoot Zn/Cd contents were greater than or similar to those in the homogeneous treatment at each metal concentration. Plants in the control treatment showed symptoms of Zn deficiency, although their shoots had Zn concentrations 100-fold higher than the critical deficiency value for most plants. We conclude that S. alfredii has evolved root foraging mechanisms associated with its greater requirements for Zn/Cd. These results could have important implications both for phytoremediation and for investigation of positive role of Cd in higher plants. © Springer Science + Business Media B.V. 2009. Source

Guo Z.-Z.,South China Agricultural University
Superlattices and Microstructures | Year: 2015

Abstract In this paper the spin transfer torque (STT) induced magnetization dynamics of graphene-based lateral spin valve (LSV) structures is investigated theoretically by using the Landau-Lifshitz-Gilbert-Slonczewski (LLGS) equation. Effect of parameters of the LSV, contact types between the ferromagnet and graphene on the STT critical current of magnetization switching in the free layer of the LSV are studied. The polarized current which is transformed from the injector to the detector (free layer) is calculated by the analytical expressions. The results show that, from the viewpoint of application as magnetic switch, tunnel contact can effectively reduce the spin torque critical current compared to the case of transparent contact. In addition, the spin-torque critical current can also be reduced by imposing a weak magnetic field, or reducing the spacing between the injector and detector. Another important feature found from the results is that, the magnetization reversal between the parallel and anti-parallel states is asymmetric, which is in agreement with the reports in literatures. © 2015 Elsevier Ltd. Source

Liu H.,Dalian Medical University | Luo M.,Chongqing Institute of Tuberculosis Prevention and Treatment | Wen J.-K.,South China Agricultural University
Journal of Zhejiang University: Science B | Year: 2014

Eukaryotic gene expression is controlled by different levels of biological events, such as transcription factors regulating the timing and strength of transcripts production, alteration of transcription rate by RNA processing, and mRNA stability during RNA processing and translation. RNAs, especially mRNAs, are relatively vulnerable molecules in living cells for ribonucleases (RNases). The maintenance of quality and quantity of transcripts is a key issue for many biological processes. Extensive studies draw the conclusion that the stability of RNAs is dedicated-regulated, occurring co- and post-transcriptionally, and translation-coupled as well, either in the nucleus or cytoplasm. Recently, RNA stability in the nucleus has aroused much research interest, especially the stability of newly-made transcripts. In this article, we summarize recent progresses on mRNA stability in the nucleus, especially focusing on quality control of newly-made RNA by RNA polymerase II in eukaryotes. © 2014 Zhejiang University and Springer-Verlag. Source

Zhang H.,Chinese University of Hong Kong | Zhuang X.,South China Agricultural University | Chu L.M.,Chinese University of Hong Kong
Restoration Ecology | Year: 2013

To understand vegetation development during the ecological succession of rehabilitated quarries, floristic composition and structure were evaluated at different restoration phases on three quarries in Hong Kong that were planted with exotic woody species over the course of 2-14 years. A total of 113 species, of which 82 were woody species, were recorded. Exotic species dominated the overstory, and species number, richness, and diversity increased with age. Some light-demanding early successional species were becoming dominant in the overstory vegetation at the older phases of revegetation. These species could be potential candidates for early enrichment planting with Acacia spp. Common secondary forest species occurred naturally in the understory vegetation, and were more abundant and dominant after 10 years of ecological development. The most successful restorations were on scree slopes using leguminous Acacia spp. as nurse species. © 2012 Society for Ecological Restoration. Source

Zhou Z.,Shanghai Normal University | Sun Y.,Shanghai Normal University | Shen J.,Shanghai Normal University | Wei J.,Shanghai Normal University | And 7 more authors.
Biomaterials | Year: 2014

The development of photothermal agents (PTAs) with good stability, low toxicity, highly targeting ability and photothermal conversion efficiency is an essential pre-requisite to near-infrared photothermal therapy (PTT) invivo. Herein, we report the readily available PEGylated Fe@Fe3O4 NPs, which possess triple functional properties in one entity - targeting, PTT, and imaging. Compared to Au nanorods, they exhibit comparable photothermal conversion efficiency (~20%), and much higher photothermal stability. They also show a high magnetization value and transverse relaxivity (~156mm-1s-1), which should be applied for magnetic targeting MRI. With the Nd-Fe-B magnet (0.5T) beside the tumour for 12h on the xenograft HeLa tumour model, PEGylated Fe@Fe3O4 NPs exhibit an obvious accumulation. In tumour, the intensity of MRI signal is ~ three folds and the increased temperature is ~ two times than those without magnetic targeting, indicating the good magnetic targeting ability. Notably, the intrinsic high photothermal conversion efficiency and selective magnetic targeting effect of the NPs in tumour play synergistically in highly efficient ablation of cancer cells invitro and invivo. © 2014 Elsevier Ltd. Source

Zhao J.,University of Florida | Cui J.,Nanjing Agricultural University | Liu J.,South China Agricultural University | Liao F.,Guangdong Academy of Agricultural Sciences | And 3 more authors.
Plant Cell, Tissue and Organ Culture | Year: 2012

This study established a method of regenerating Spathiphyllum 'Supreme' through direct somatic embryogenesis. Somatic embryos occurred in leaf and petiole explants cultured in the dark on a Murashige and Skoog basal medium supplemented with 2.27, 4.54, or 9.08 μM N-phenyl-N′-1,2,3-thiadiazol-5-ylurea (TDZ) in combination with 1.08 μM α-naphthalene acetic acid or 2.26 μM 2,4-dichlorophenoxyacetic acid (2,4-D). Explants with somatic embryos were transferred to fresh medium containing the same concentrations of growth regulators under lighted conditions for embryo conversion. The highest frequencies of leaf explants with somatic embryos and embryo conversion were both 84.4 %, which were induced by 9.08 μM TDZ with 2.26 μM 2,4-D. The frequencies for somatic embryo induction and embryo conversion were both 100 % when petiole explants were induced by 4.54 μM TDZ with 2.26 μM 2,4-D. The number of plantlets produced per leaf explant and petiole explant were as high as 67.4 and 74.4, respectively. Plantlets after transplanting to a soilless substrate grew vigorously in a shaded greenhouse. Liners were stable without phenotypic variation. Flow cytometry analysis of randomly selected plants showed that they all had a single identical peak. The mean nuclear DNA index for 'Supreme' was 1.568, and the nuclear DNA content was 14. 222 pg 2C -1. The estimated genome size for 'Supreme' was 6,954. 5 Mbp 1C -1 with a CV at 4.008 %. The results suggest that the regenerated plants have a stable ploidy level and this established regeneration method can be used for highly effective propagation of uniform Spathiphyllum 'Supreme'. © 2012 Springer Science+Business Media B.V. Source

Li Z.,Oklahoma State University | Wang N.,Oklahoma State University | Hong T.,South China Agricultural University
Transactions of the ASABE | Year: 2010

Wireless sensor network (WSN) technology is a promising solution for large-scale, real-time, and continuous soil property data acquisition. However, the applications are still very limited due to a lack of understanding of in-field data transmission performance of a WSN. In this study, commercial 2.4 GHz wireless sensor modules (referred to as "motes") and a hand-held spectrum analyzer were used to set up a test platform to evaluate radio propagation performance. Indexed packets transmitted from a module were captured by the spectrum analyzer to measure path-loss through received signal strength (RSS) and synchronously received by another module, called the base station, to calculate packet delivery rate (PDR). Experiments were conducted in a wheat field of an experimental farm of Oklahoma State University. Canopy height, transmitter height, receiver height, and transmitter-to-receiver distance (T-R distance) were considered as impact factors on radio propagation. Correlation analysis was used to evaluate the relationship between path-loss and PDR. The results indicated that, as plant height increased, path-loss and PDR became more correlated with each other. A distance of 70 m was defined as a stable communication distance for 2.4 GHz in-field WSN applications. Four models were developed to predict the path-loss based on the log of T-R distance and transmitter and receiver heights under conditions of clear line-of-sight and three different plant canopy heights. The R 2 values of the models were 0.601, 0.599, 0.674, and 0.776, respectively. Their standard errors of the estimate were 3.761, 3.199 3.518, and 2.889, respectively. ©; 2010 American Society of Agricultural and Biological Engineers. Source

Gan Y.,South China University of Technology | Luo Y.,South China University of Technology | Feng Q.,Guangzhou China Resources Thermal Power Co. | Shi Y.,South China Agricultural University
Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery | Year: 2014

The characteristics of ethanol-air microscale laminar-flow diffusion combustion were investigated. Combined with experimental study and numerical simulation, the effects of surface heat loss on the flame stability in the confined space were systematically analyzed. The surface heat loss was controlled by electrical heating inside. According to the results, the electrical heating reduced the effects of heat loss and enhanced the stability effectively. Using the appropriate electrical heating power, it reached the widest stability limits of combustion. The flame feature size and temperature distribution were both changed by the electrical heating. The electrical heating raised the flame temperature. The chemical reaction rate became bigger, and the micro-flame shifed upstream. Within a certain range, the electrical heating increase was greater than the increase of the heat loss. The electrical heating inhibited the heat loss and enhanced the stability. Source

Liu Q.,South China Agricultural University | Mathanker S.K.,University of Illinois at Urbana - Champaign | Zhang Q.,Washington State University | Hansen A.C.,University of Illinois at Urbana - Champaign
Transactions of the ASABE | Year: 2012

Miscanthus × giganteus is emerging as one of the most promising crops suitable for biomass production, as it requires low inputs and produces high yields. Miscanthus harvesting using forage and hay equipment presents a challenge because of the thickness and hardness of miscanthus stems. Biomechanical properties of the miscanthus stems were investigated for use in designing better harvesting and size reduction equipment. Material testing equipment was used to study cutting force, shearing strength, tensile strength, and bending strength. The cutting force was determined at the first internode, whereas other properties were determined at internodes one through seven. The shear strength of miscanthus stems at the first or second internode was about double that at internodes three through seven. Tensile strength of the cortex in the cross-sectional direction was about 0.4% of tensile strength in the longitudinal direction. Shearing strength of the cortex was 7.0 and 65.0 MPa and tensile strength was 288.1 and 1.1 MPa in the longitudinal and cross-sectional directions, respectively. The modulus of elasticity of miscanthus stems increased from 4,600 to 11,300 MPa as the internode number increased from first to seventh. The maximum cutting force to cut miscanthus stems was 83.0 N mm -1 for a flat blade and 54.6 N mm -1 for a serrated blade. The specific cutting energy was 87.5 mJ mm -2 for the flat blade and 66.1 mJ mm-2 for the serrated blade. Analysis revealed that the serrated blade employed less energy-demanding modes of failure than the flat blade, resulting in lower cutting energy and reduced cutting force. The results of this study may be useful in designing harvesting and size reduction equipment employing optimum failure modes to minimize the energy or to achieve desired quality of cut. © 2012 American Society of Agricultural and Biological Engineers. Source

Both Microplitis prodeniae Rao and Chandry (Hymenoptera: Bracondidae) and Campoletis chlorideae Uchida (Hymenoptera: Ichnumonidae) are major parasitoids of Spodoptera litura (Fabricious) (Lepidoptera: Noctuidae) in tobacco, Nicotiana tabacum L. (Solanales: Solanaceae) at Nanxiong, Guangdong Province, South China. The niches and interspecific competition relationships of the two species were studied. The results show that the competition between the two species for spatial and food resources was very intense, and C. chlorideae was always dominant when the two species compete for spatial and food resources in different periods. Thus C. chlorideae may drive M. prodeniae away when they occupy the same spatial or food resource. The adaptability of C. chlorideae to the environment in the tobacco fields may be greater than that of M. prodeniae, so C. chlorideae can maintain a higher population compared to that of M. prodeniae. Source

Zhang A.,South China University of Technology | Zhang A.,South China Agricultural University | Lu F.,University of Wisconsin - Madison | Liu C.,South China University of Technology | And 2 more authors.
Journal of Agricultural and Food Chemistry | Year: 2010

A three-step sequential extraction-precipitation method was used to isolate lignin from Eucalyptus tereticornis. The ball-milled eucalyptus was extracted with 96% dioxane, 50% dioxane, and 80% dioxane containing 1% NaOH at boiling temperature, consecutively resulting in solubilization of lignin and hemicelluloses. By precipitating such solutions into 70% aqueous ethanol, the hemicelluloses were removed substantially although there were still some carbohydrates left over, especially for lignin fraction extracted by 50% dioxane. Lignins dissolved in the 70% ethanol solutions were recovered via concentration and precipitation into acidified water. About 37% of the original lignin was released following such procedure whereas only 13.5% can be isolated by traditional milled wood lignin (MWL) method. The obtained lignin fractions were analyzed by high performance anion exchange chromatography (HPAEC) following acid hydrolysis for sugar composition of the contaminating carbohydrates and characterized by quantitative 31P NMR as well as two-dimensional heteronuclear single-quantum coherence (13C- 1H) NMR. The results showed that 96% aqueous dioxane extraction of ball-milled wood under conditions used in this study resulted in lignin preparation with very similar structures and sugar composition as traditional MWL. Therefore extracting ball-milled wood with 96% aqueous dioxane produced lignin in 33.6% yield, which makes it very attractive as an alternative to the traditional MWL method. However further extraction with 50% aqueous dioxane or 80% aqueous dioxane containing 1% NaOH gave just a little more lignins with different carbohydrate compositions from those in MWL. The eucalyptus lignins obtained were syringyl and guaiacyl type units. Lignin fraction obtained from 96% dioxane extraction was found to have more phenolic hydroxyl and less aliphatic hydroxyl than the other two preparations. © 2010 American Chemical Society. Source

Zhang G.,University of Wisconsin - Madison | Ll B.,South China Agricultural University | Lee C.-H.,University of Wisconsin - Madison | Lee C.-H.,National Chung Hsing University | Parkin K.L.,University of Wisconsin - Madison
Journal of Agricultural and Food Chemistry | Year: 2010

The chemical syntheses of cysteine (CYS) and glutathione (GSH) mixed -disulfide conjugates (CySSR, GSSR, respectively) of mercapto residues representing most of the R groups of thiosulfinates (R = methyl, ethyl, propyl, and allyl) are described. Gram-scale conjugates were prepared as >98% pure preparations, with 80% reaction yield for each of the two seminal synthesis steps, with structures confirmed by 1H NMR and high-resolution MS analyses. These conjugates are derivatives of thiosulfinates that may be evolved in processed foods, in the digestive tract, and through in vivo metabolism. The prepared conjugates were found to be able to induce quinone reductase (QR, a representative phase II enzyme) in murine hepatoma cells (Hepa 1c1c7) and to inhibit nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated macrophage cells (RAW 264.7), indicating they have potential cancer preventive and anti-inflammatory activities. Among the prepared conjugates, the allyl conjugates of CYS and GSH, S-allylmercaptocysteine (CySSA) and S-allylmercaptoglutathione (GSSA), showed the most potent activity regarding QR induction and NO production inhibition. The conjugates with saturated R groups were also active and conferred biological activity as cystine and oxidized glutathione exhibited no effects in these cellular assays. © 2010 American Chemical Society. Source

Chen J.,Chinese Academy of Agricultural Sciences | Chen J.,South China Agricultural University | Xu M.-J.,Chinese Academy of Agricultural Sciences | Zhou D.-H.,Chinese Academy of Agricultural Sciences | And 5 more authors.
Parasites and Vectors | Year: 2012

Canine and feline parasitic zoonoses have not been given high priority in China, although the role of companion animals as reservoirs for zoonotic parasitic diseases has been recognized worldwide. With an increasing number of dogs and cats under unregulated conditions in China, the canine and feline parasitic zoonoses are showing a trend towards being gradually uncontrolled. Currently, canine and feline parasitic zoonoses threaten human health, and cause death and serious diseases in China. This article comprehensively reviews the current status of major canine and feline parasitic zoonoses in mainland China, discusses the risks dogs and cats pose with regard to zoonotic transmission of canine and feline parasites, and proposes control strategies and measures. © 2012 Chen et al. Source

Cheng S.,GeCheng Global Eco Technology Inc. | Yang G.,CAS Chengdu Institute of Mountain Hazards and Environment | Yang G.,University of Chinese Academy of Sciences | Yu H.,CAS Chengdu Institute of Mountain Hazards and Environment | And 3 more authors.
Ecological Indicators | Year: 2012

How earthquake-induced landslides impact the growth of existing trees remains unknown worldwide. Therefore, we established an experiment with two tree species (Cupressus funebris, Cryptomeria fortunei) and two landslide conditions (non-impacted and impacted stands) near the northern section of the fault belt one year after the Wenchuan Earthquake (8.0 M s) that occurred in China in 2008. At site I, two plots of each species were located in non-impacted stands. At site II, three plots of Cu. funebris were established in non-impacted stands, and three plots were established in impacted stands. At site III, three plots of Cr. fortunei were placed in non-impacted stands, while two plots were placed in impacted stands. All plots were 20 m × 20 m in size. At each plot, we measured the diameter at breast height and the height of each tree and used their mean values to select five trees representing average growth. Two to three small fine roots (≤2.0 mm in diameter, >20 cm long) were sampled in just three of the five selected trees to investigate root parameters. Leaf, branch and root water contents of the sampled trees were also examined. Soil samples were collected from 0 to 10, 10 to 20 and 20 to 40 cm depths at the center and near the four corners of each plot to analyze soil physical properties. The study revealed that saturated water content, capillary moisture capacity, field water capacity, total porosity and capillary porosity were lower in the impacted stands than in the non-impacted stands. Conversely, bulk density was higher in the impacted stands, indicating that the soils in the impacted stands had become compacted and dry. Soil water content, saturated water content, capillary moisture capacity, field water capacity, total porosity, capillary porosity and non-capillary porosity were greater in Cr. fortunei stands than in Cu. funebris stands, while bulk density was lower, indicating that impacted stands of Cu. funebris were more compacted and dry than those of Cr. fortunei. In impacted Cu. funebris stands, mean tip length/length and mean tip length/biomass decreased, while plant organ water contents did not change. In impacted Cr. fortunei stands, in contrast, these root parameters as well as specific root area, specific root length and leaf water content increased. These patterns suggest Cr. funebris experiences a much higher root growth than Cu. funebris in landslide impacted stands. Survival and recovery may be more difficult for Cu. funebris than for Cr. fortunei. © 2011 Elsevier Ltd. All rights reserved. Source

Situ H.,South China Agricultural University
Quantum Information Processing | Year: 2015

We use one of the influential quantum game models, the Marinatto–Weber model, to investigate quantum Bayesian game. We show that in a quantum Bayesian game which has more than one Nash equilibrium, one equilibrium stands out as the compelling solution, whereas two Nash equilibria seem equally compelling in the classical Bayesian game. © 2015, Springer Science+Business Media New York. Source

Liu G.F.,South China Agricultural University | Li M.,Nanjing Agricultural University | Wen J.,Nanjing Agricultural University | Du Y.,Nanjing Agricultural University | Zhang Y.-M.,Nanjing Agricultural University
Molecular Genetics and Genomics | Year: 2010

Several biologically significant parameters that are related to rice tillering are closely associated with rice grain yield. Although identification of the genes that control rice tillering and therefore influence crop yield would be valuable for rice production management and genetic improvement, these genes remain largely unidentified. In this study, we carried out functional mapping of quantitative trait loci (QTLs) for rice tillering in 129 doubled haploid lines, which were derived from a cross between IR64 and Azucena.We measured the average number of tillers in each plot at seven developmental stages and fit the growth trajectory of rice tillering with the Wang-Lan-Ding mathematical model. Four biologically meaningful parameters in this model-the potential maximum for tiller number (K), the optimum tiller time (t 0), and the increased rate (r), or the reduced rate (c) at the time of deviation from t0-were our defined variables for multi-marker joint analysis under the framework of penalized maximum likelihood, as well as composite interval mapping. We detected a total of 27 QTLs that accounted for 2.49-8.54% of the total phenotypic variance. Nine common QTLs across multi-marker joint analysis and composite interval mapping showed high stability, while one QTL was environment-specific and three were epistatic. We also identified several genomic segments that are associated with multiple traits. Our results describe the genetic basis of rice tiller development, enable further marker-assisted selection in rice cultivar development, and provide useful information for rice production management. © Springer-Verlag 2010. Source

Gao J.,South China Normal University | Wang N.,Nanyang Technological University | Xiong X.,South China University of Technology | Chen C.,South China Normal University | And 5 more authors.
CrystEngComm | Year: 2013

To explore the influence of different carboxylate ligands on the structures of metal-organic frameworks (MOFs), five novel Zn(ii) coordination polymer compounds, namely, {[Zn(atz)(bia)]}n (1), {[Zn3(atz) 3(tpa)3/2]}n (2), {[Zn2(atz) 2(pda)]}n (3), {[Zn4(atz)2(btc)] ·4H2O}n (4) and {[Zn2(atz) 2(btec)]·H2O}n (5) have been successfully obtained by introducing various secondary auxiliary ligands in Zn(ii)-L systems, characterized by elemental analysis, FT-IR, thermogravimetric analysis (TGA), powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction (Hatz = 3-amino-1,2,4-triazolate, Hbia = benzoic acid, H 2tpa = 1,4-terephthalic acid, H2pda = 1,4-benzenediacetic acid, H3btc = 1,3,5-benzenetricarboxylate, H4btec = 1,2,4,5-benzenetetracarboxylic). Compound 1 features a 2D layer with (4.8 2) topology, which is further stabilized by hydrogen bonds between the uncoordinated amino groups and uncoordinated oxygen atoms from bia ligands. Compound 2 exhibits a 3D 3,4-connected framework with {4.82.10 3}{4.82} topology, constructed from Zn(ii) ions and μ3-atz ligand. Compound 3 displays a 3D 3,4-connected network with {4.6.8}{4.62.83} topology. Compound 4 possesses a 3D 9-nodal network with a point symbol of {4.8.9}2{4.8 2}{}{5.8.9}4{5.82}. Compound 5 shows a 3D 3,4,4-connected framework with {4.82} 4{42.83.10}2{84.10 2} topology. The diverse structures of these five complexes demonstrate that the skeleton of carboxylate ligands have a significant impact on the construction of MOFs. Moreover, the luminescence properties of complexes 1-5 were investigated in the solid state. © 2013 This journal isThe Royal Society of Chemistry. Source

Liu J.T.,South China Agricultural University
Dong wu xue yan jiu = Zoological research / "Dong wu xue yan jiu" bian ji wei yuan hui bian ji | Year: 2011

Accumulated evidence indicates that the activating transcription factor 4 (atf4) is a developmentally relevant gene. Here, we report on the characterization of atf4 in Xenopus embryos, which is differentially expressed in the central nervous system, eyes, blood, and the pronephros, as well as in developing endodermal organs such as the stomach, duodenum, liver, and pancreas. Ectopic expression of atf4 in the animal hemisphere of Xenopus embryos had no obvious effects on the induction of neural progenitors, but suppressed neurogenesis and eye formation without promoting apoptosis. Our data suggest that tightly controlled atf4 activities may be crucial for normal neurogenesis and early eye patterning. Source

Zhang W.-F.,South China Agricultural University | Yan H.,City University of Hong Kong
Pattern Recognition | Year: 2012

Spectrum analysis approaches, such as the Fourier transform, wavelet transform and autoregressive model, have been successfully applied to solve the exon prediction problem due to their flexibility that requires no training data or prior knowledge. Detecting short exons is a difficult problem. The results achieved by the traditional methods are often unsatisfactory, because they cannot identify spectral patterns of short exons correctly. In this article, we propose an improved exon prediction method based on empirical mode decomposition and the Fourier transform. The proposed approach numerically represents the DNA sequences by their structural features, which can help to yield significant patterns that are rarely observed with the traditional methods. The structural profile is utilized to detect probable exons by examining the peaks of the local 1/3 frequency spectrum within a sliding window. The data in the window is firstly decomposed by empirical mode decomposition into a collection of intrinsic mode functions. Then the first intrinsic mode function is used to compute the local spectrum by fast Fourier transform. We compare our method with the traditional Fourier transform with binary representation method and the recently proposed paired spectral content method. Experiments on randomly selected Human genome dataset and the GENSCAN benchmark dataset illustrate that our method can enhance the signal-to-noise ratio of the analyzed sequences and improve the prediction accuracy of short exons. © 2011 Elsevier Ltd. All rights reserved. Source

Cao S.,South China Agricultural University | Cao S.,South China Normal University | Shan C.-J.,South China Normal University | Shan C.-J.,Hubei Normal University | And 4 more authors.
Journal of the Optical Society of America B: Optical Physics | Year: 2015

We numerically investigate the ground state, the Raman-driving dynamics, and the nonlinear excitations of a realized spin-orbit-coupled Bose-Einstein condensate in a 1D harmonic trap. Depending on the Raman coupling and the interatomic interactions, three ground-state phases are identified: stripe, plane wave, and zero-momentum phases. A narrow parameter regime with coexistence of stripe and zero-momentum or plane wave phases in real space is found. Several sweeps progress across different phases by driving the Raman coupling linearly in time are simulated and the nonequilibrium dynamics of the system in these sweeps are studied. We find several kinds of nonlinear excitations, with the particular dark solitons excited in the sweep from the stripe phase to the plane wave or zero-momentum phase within the trap. Moreover, the number and the stability of the dark solitons can be controlled in the driving, which provides a direct and easy way to generate dark solitons and study their dynamics and interaction properties. © 2015 Optical Society of America. Source

Yu H.-Y.,Guangdong Institute of Eco environmental and Soil Sciences | Li F.-B.,Guangdong Institute of Eco environmental and Soil Sciences | Yu W.-M.,Guangdong Institute of Eco environmental and Soil Sciences | Li Y.-T.,South China Agricultural University | And 5 more authors.
Science of the Total Environment | Year: 2013

High levels of organochlorine pesticides (OCPs) such as hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) have been found in soil of the Pearl River Delta (PRD), attributable to high pesticide application in this area. Consequently, the occurrence and environmental effect of HCHs and DDTs in the PRD have attracted considerable attention. However, study focusing on the influence of potential factors such as soil property on the environmental fate of HCHs and DDTs in the PRD has been rare. The present study aimed to investigate the impact of soil physiochemical properties on the distribution patterns and fate of soil HCHs and DDTs on a large spatial scale. Levels of HCHs (sum of α-, β-, γ- and δ-HCH) and DDTs (sum of 1,1,1-trichloro-2,2-bis-(p-chlorophenyl)ethane (p,. p'-DDT), 1,1-dichloro-2,2-bis-(p-chlorophenyl)ethane (p,p'-DDD), and 1,1-dichloro-2,2-bis-(p-chlorophenyl)ethylene (p,. p'-DDE)) in 151 soil samples covering all areas of the PRD and physiochemical parameters related to soil properties including pH, total organic carbon (TOC), total Fe (TFe), DCB-Fe (DFe), amorphous-Fe (AFe), complexed-Fe (CFe), total Mn (TMn), DCB-Mn (DMn), amorphous-Mn (AMn), complexed-Mn (CMn) and cation exchange capacity (CEC) were determined. The residual levels of HCHs and DDTs in soils of the present study, which are mainly controlled by soil TOC and CFe content and varying spatially with land use types, may potentially pose ecological risk to plants and animals. On the other hand, transformation of soil HCHs may be affected by pH and DDT transformation correlated significantly with AFe and CFe. Currently, soil has become an important secondary source of OCPs and the re-emission potential of OCPs in soil was mainly affected by soil OCP concentrations and land use types. © 2012 Elsevier B.V. Source

Wu B.,South China University of Technology | Tang G.,South China University of Technology | Tang G.,South China Agricultural University
Jianzhu Jiegou Xuebao/Journal of Building Structures | Year: 2010

This paper presents the state-of-the-art of fire-resistance study on concrete structures including retrofitted structures and re-used structures in recent year, and discusses some issues that still need to be investigated. Based on the extensive literatures, the developing trends of fire-resistance research of concrete structures are suggested. The 'Regulations for fire resistance of concrete building structures' currently under preparation is introduced briefly. It can be seen that since the heating time related to the deformation limit state is generally very close to that corresponding to the load-bearing capacity limit state for concrete structures at high temperature, and considering the design practice at room temperature, the fire resistance design may be conducted based on the load-bearing capacity limit state at elevated temperature. Random fire resistance of structures, cooperative action of structural members at high temperature, fire behavior of global structures, and fire resistance of control devices are main problems for concrete structures in fire and need to be studied in the future. Source

Golovatch S.I.,RAS A.N. Severtsov Institute of Ecology and Evolution | Liu W.,South China Agricultural University | Geoffroy J.-J.,CNRS Science Conservation Center
Zootaxa | Year: 2012

China is shown to currently support 23 species of the large, basically warm temperate to tropical Asian genus Hyleoglomeris, all keyed and mapped, including 15 new ones: H. tiani sp. n., H. xia sp. n. and H. youhao sp. n. from Hunan Province, H. wuse sp. n., H. nigu sp. n., H. gudu sp. n. and H. yinshi sp. n. from Guizhou Province, as well as H. qiyi sp. n., H. lii sp. n., H. heshang sp. n., H. xueju sp. n., H. mulunensis sp. n., H. mashanorum sp. n., H. curtisulcata sp. n. and H. kunnan sp. n. from Guangxi Province. Hyleoglomeris eusulcata Golovatch, Geoffroy & Mauriès, 2006 has been recorded and redescribed from a new, near-topotype sample. Two new species groups are being proposed: the venustula- and the albicorporis-group. The status of Nearctomeris Wesener, 2012, a monobasic genus from the eastern USA, is questioned viz-à-viz Hyleoglomeris, albeit no formal synonymy is being proposed. Copyright © 2012 Magnolia Press. Source

Ye N.,Hong Kong Baptist University | Zhu G.,South China Agricultural University | Liu Y.,Shandong Agricultural University | Li Y.,Hong Kong Baptist University | Zhang J.,Hong Kong Baptist University
Plant and Cell Physiology | Year: 2011

The production of both ABA and H 2O 2 is induced by drought and can act as signals under stress conditions. We investigated the relationships between ABA, H 2O 2 and catalase (CAT) in rice leaves when rice seedlings were treated with polyethylene glycol as water stress treatment. As a key gene in ABA biosynthesis, OsNCED3 was significantly induced in rice by water stress treatment and such induction preceded the rapid increase in ABA. Water stress inhibited the expression of CATA and CATC but substantially enhanced the expression of CATB. Exogenously applied ABA promoted the expression of CATB also and inhibited the expression of CATC in a concentration-dependent manner. When ABA production was inhibited by using ABA biosynthesis inhibitors nordihydroguaiaretic acid and tungstate, expression of CATB was also subdued while CATC was enhanced under the water stress. Accumulation of H 2O 2 was also reduced when endogenous ABA production was inhibited and showed a correlation with the total activity of catalases. Our results suggest that water stress-induced ABA prevents the excessive accumulation of H 2O 2, through the induction of the expression of CATB gene during water stress. © 2011 The Author. Source

Yu X.-Y.,South China Agricultural University | Hu G.-R.,Central South University | Liu Y.-X.,Central South University
Zhongguo Youse Jinshu Xuebao/Chinese Journal of Nonferrous Metals | Year: 2010

Layered LiNi1/3Co1/3Mn1/3-x MxO2 (M= Mg, Al, Cr) cathode materials for lithium-ion battery were synthesized by co-precipitation method. The structures, morphologies, electrochemical properties and kinetic parameters of the LiNi1/3Co1/3Mn1/3-x MxO2 cathode materials were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), charge/discharge tests and electrochemical impedance spectroscopy (EIS). The results show that the LiNi1/3Co1/3Mn1/3-x MxO2 cathode materials (M=Mg2+, Al3+; x=0.05) exhibit initial capacity of 139.2 and 151.6 mA·h/g in the voltage range of 2.8-4.3 V, and at 0.1C rate, the capacities retain 98.8% and 96.7% after 20 cycles, respectively. Mg2+ or Al3+ doping can enhance the exchange current density and diffusion coefficient of LiNi1/3Co1/3Mn1/3-x MxO2 materials. Based on the ionic radius and chemical stability of doped metal ions, the occupation in the structure and the role of the doped metal ions during charge-discharge cycling were discussed. Source

Liu Z.-W.,South China University of Technology | Peng F.,South China University of Technology | Wang H.-J.,South China University of Technology | Yu H.,South China University of Technology | And 2 more authors.
Angewandte Chemie - International Edition | Year: 2011

Current events: A phosphorus-doped, graphite layer catalyst without any metal residue has been developed that shows high electrocatalytic activity, long-term stability, and excellent tolerance to cross-over effects of methanol in the oxygen reduction reaction. The oxygen reduction current densities of the glassy carbon (GC) electrode modified by the P-doped graphite (see red line in the picture) are much larger than those of the unmodified (blue line) and the GC electrode modified by a platinum-carbon catalyst (data not shown). Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Xiong W.,Sun Yat Sen University | Xiong W.,South China Agricultural University | Zhong F.,Sun Yat Sen University | Fan S.,Sun Yat Sen University | Fan S.,Shaanxi Normal University
Computer Physics Communications | Year: 2012

Whereas the stability of a pure critical system is determined by the sign of its specific-heat critical exponent α according to Harris criterion, whether a d-dimensional dirty system should satisfy ν≥2/d and α<0 or not has been a controversial issue for several decades, where ν is its correlation-length critical exponent. Here, contrary to recent analytical and numerical results, we find for the three-dimensional three-state random-bond Potts model whose pure version exhibits a first-order phase transition a random fixed point whose ν<2/d and α>0 using a finite-time scaling combining with extended dynamic Monte Carlo renormalization-group method. This suggests further studies are still needed to clarify the issue in three-dimensional systems. © 2012 Elsevier B.V. All rights reserved. Source

Ouyang Y.,U.S. Department of Agriculture | Zhang J.-E.,South China Agricultural University | Parajuli P.,Mississippi State University
Environmental Science and Pollution Research | Year: 2013

Characterization of groundwater quality allows the evaluation of groundwater pollution and provides information for better management of groundwater resources. This study characterized the shallow groundwater quality and its spatial and seasonal variations in the Lower St. Johns River Basin, Florida, USA, under agricultural, forest, wastewater, and residential land uses using field measurements and two-dimensional kriging analysis. Comparison of the concentrations of groundwater quality constituents against the US EPA's water quality criteria showed that the maximum nitrate/nitrite (NOx) and arsenic (As) concentrations exceeded the EPA's drinking water standard limits, while the maximum Cl, SO4 2 -, and Mn concentrations exceeded the EPA's national secondary drinking water regulations. In general, high kriging estimated groundwater NH4 +concentrations were found around the agricultural areas, while high kriging estimated groundwater NOxconcentrations were observed in the residential areas with a high density of septic tank distribution. Our study further revealed that more areas were found with high estimated NOxconcentrations in summer than in spring. This occurred partially because of more NOxleaching into the shallow groundwater due to the wetter summer and partially because of faster nitrification rate due to the higher temperature in summer. Large extent and high kriging estimated total phosphorus concentrations were found in the residential areas. Overall, the groundwater Na and Mg concentration distributions were relatively more even in summer than in spring. Higher kriging estimated groundwater As concentrations were found around the agricultural areas, which exceeded the EPA's drinking water standard limit. Very small variations in groundwater dissolved organic carbon concentrations were observed between spring and summer. This study demonstrated that the concentrations of groundwater quality constituents varied from location to location, and impacts of land uses on groundwater quality variation were profound. © 2013 Springer-Verlag Berlin Heidelberg (outside the USA). Source

Qi W.,South China Agricultural University
Euro surveillance : bulletin Européen sur les maladies transmissibles = European communicable disease bulletin | Year: 2014

Human infection with a novel influenza A(H10N8) virus was first described in China in December 2013. However, the origin and genetic diversity of this virus is still poorly understood. We performed a phylogenetic analysis and coalescent analysis of two viruses from the first case of influenza A(H10N8) (A/Jiangxi-Donghu/346-1/2013 and A/Jiangxi-Donghu/346-2/2013 and a novel A(H10N8) virus (A/chicken/Jiangxi/102/2013) isolated from a live poultry market that the patient had visited. The haemagglutinin (HA), neuraminidase (NA), PA subunit of the virus polymerase complex, nucleoprotein (NP), M and nonstructural protein (NS) genes of the three virus strains shared the same genetic origins. The origins of their HA and NA genes were similar: originally from wild birds to ducks, and then to chickens. The PA, NP, M, and NS genes were similar to those of chicken influenza A(H9N2) viruses. Coalescent analyses showed that the reassortment of these genes from A(H9N2) to A(H10N8) might have occurred at least twice. However, the PB1 and PB2 genes of the chicken A(H10N8) virus most likely originated from H7-like viruses of ducks, while those of the viruses from the case most likely stemmed from A(H9N2) viruses circulating in chickens. The oseltamivir-resistance mutation, R292K (R291K in A(H10N8) numbering) in the NA protein, occurred after four days of oseltamivir treatment. It seems that A(H10N8) viruses might have become established among poultry and their genetic diversity might be much higher than what we have observed. Source

Zhang H.N.,South China Agricultural University
Avian pathology : journal of the W.V.P.A | Year: 2011

Subgroup J avian leukosis virus (ALV-J), first isolated in 1989, mainly induces tumours of myeloid leukosis (ML) in meat-type chickens. In 2006, ALV-J strain SCAU-HN06 was isolated from commercial layer hens with spontaneous haemangiomas in China. To confirm its role in the induction of haemangioma, we constructed a full-length copy of the proviral genome from SCAU-HN06, recovered virus from DF-1 cells detected by enzyme-linked immunosorbent assay, characterized its growth property and investigated its pathogenicity. The recovered virus appeared to be identical to SCAU-HN06 analysed by both blast gene sequences and indirect immunofluorescence assay. It also showed similarities in growth to the parental wild-type virus in vitro. The pathogenicity of the rescued and parental virus in specific-pathogen-free White Leghorn chickens was investigated. Both SCAU-HN06 and rSCAU-HN06 could induce haemangioma, with incidence of 52% and 42.8% respectively. Overall, our findings indicated that the ALV-J strain SCAU-HN06 was the causal agent inducing haemangiomas rather than ML in certain layer chickens. Source

Yu H.,South China University of Technology | Peng F.,South China University of Technology | Tan J.,South China University of Technology | Hu X.,South China University of Technology | And 3 more authors.
Angewandte Chemie - International Edition | Year: 2011

Putting the N in nanotube: Carbon nanotubes (CNTs) catalyze the aerobic oxidation of cyclohexane into cyclohexanol, cyclohexanone, and adipic acid with excellent activity and controllable selectivity. The catalytic activity is further enhanced by nitrogen dopants in the nanotube (see diagram; AC=activated carbon, MWCNT=multiwalled CNT, N-CNT=nitrogen-doped CNT). © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Cheng Y.,Zhejiang University | Cheng Y.,Purdue University | Zhou Y.,Zhejiang University | Yang Y.,Zhejiang University | And 10 more authors.
Plant Physiology | Year: 2012

WRKY transcription factors are encoded by a large gene superfamily with a broad range of roles in plants. Recently, several groups have reported that proteins containing a short VQ (FxxxVQxLTG) motif interact with WRKY proteins. We have recently discovered that two VQ proteins from Arabidopsis (Arabidopsis thaliana), SIGMA FACTOR-INTERACTING PROTEIN1 and SIGMA FACTOR-INTERACTING PROTEIN2, act as coactivators of WRKY33 in plant defense by specifically recognizing the C-terminal WRKY domain and stimulating the DNA-binding activity of WRKY33. In this study, we have analyzed the entire family of 34 structurally divergent VQ proteins from Arabidopsis. Yeast (Saccharomyces cerevisiae) two-hybrid assays showed that Arabidopsis VQ proteins interacted specifically with the C-terminal WRKY domains of group I and the sole WRKY domains of group IIc WRKY proteins. Using site-directed mutagenesis, we identified structural features of these two closely related groups of WRKY domains that are critical for interaction with VQ proteins. Quantitative reverse transcription polymerase chain reaction revealed that expression of a majority of Arabidopsis VQ genes was responsive to pathogen infection and salicylic acid treatment. Functional analysis using both knockout mutants and overexpression lines revealed strong phenotypes in growth, development, and susceptibility to pathogen infection. Altered phenotypes were substantially enhanced through cooverexpression of genes encoding interacting VQ and WRKY proteins. These findings indicate that VQ proteins play an important role in plant growth, development, and response to environmental conditions, most likely by acting as cofactors of group I and IIc WRKY transcription factors. © 2012 American Society of Plant Biologists. Source

Huang S.,South China Agricultural University | Yang C.,Huazhong University of Science and Technology
Advances in Information Sciences and Service Sciences | Year: 2012

This paper examines the pricing and production quantity decisions in a supply chain composed of one manufacturer and one retailer with demand-stimulating service under demand disruptions. The model proposed contains two consecutive periods, where in the first period a production plan is made based on anticipated market demand and in the second period the actual demand is detected. The decision-maker should determine how to adjust the selling price, demand-stimulating service level and production quantity to maximize profit. The problem is analyzed in a centralized and decentralized supply chain, respectively. It is found that the original production quantity and demand-stimulating service level have some robustness under demand disruptions both in centralized and decentralized supply chains. In centralized supply chains, it is always beneficial for the central decision-maker to know of the accurate value of demand disruptions, however, it is not always beneficial for the retailer to reveal the accurate demand disruption information to the manufacturer in decentralized supply chains, and the manufacturer may benefit from the retailer's concealing information. Source

Lin J.,South China Agricultural University | Lu Y.,Huazhong University of Science and Technology | Wang B.,University of Texas-Pan American | Wei K.K.,City University of Hong Kong
Electronic Commerce Research and Applications | Year: 2011

Mobile brokerage services represent an emerging application of mobile commerce in the brokerage industry. Compared with telephone-based trading services and online brokerage services, they have advantages such as ubiquity, convenience, and privacy. However, the number of investors using mobile brokerage services to conduct brokerage transactions is far smaller than those using other trading methods. A plausible reason for this is that investors lack initial trust in mobile brokerage services, which affects their acceptance of them. This research examines trust transfer as a means of establishing initial trust in mobile brokerage services. We analyze how an investor's trust in the online brokerage services of a brokerage firm affects her cognitive beliefs about the mobile brokerage services of the firm and what other key factors influence the formation of initial trust in mobile brokerage services. We develop and empirically test a theoretical model of trust transfer from the online to the mobile channels. Our results indicate that trust in online brokerage services not only has a direct effect on initial trust but also has an indirect effect through other variables. This study provides useful suggestions and implications for academics and practitioners. © 2011 Elsevier B.V. All rights reserved. Source

Wen Y.-W.,South China Agricultural University | Liu C.,National University of Singapore | Yip A.M.,National University of Singapore
Applied Optics | Year: 2010

We consider the recovery of degraded videos without complete knowledge about the degradation. A spatially shift-invariant but temporally shift-varying video formation model is used. This leads to a simple multiframe degradation model that relates each original video frame with multiple observed frames and point spread functions (PSFs). We propose a variational method that simultaneously reconstructs each video frame and the associated PSFs from the corresponding observed frames. Total variation (TV) regularization is used on both the video frames and the PSFs to further reduce the ill-posedness and to better preserve edges. In order to make TV minimization practical for video sequences, we propose an efficient splitting method that generalizes some recent fast single-image TV minimization methods to the multiframe case. Both synthetic and real videos are used to show the performance of the proposed method. © 2010 Optical Society of America. Source

Nie P.-Y.,Jinan University | Chen Y.-H.,South China Agricultural University
Agricultural Economics (Czech Republic) | Year: 2014

By establishing a dynamic equilibrium model, the paper analyses the equilibrium of the food industry and the equilibrium about the food quality as well as quantity is achieved. Firstly, the study examines the effects of competitions on the price, outputs, profits and social welfare. The authors argue that competition reduces the food quality. Secondly, this paper shows that consumers benefit from the quality regulation while producers undertake a loss. Moreover, social welfare first increases then decreases with the regulation. Thirdly, the optimal quality regulation is presented and a higher quality regulation reduces competition, while the lower quality regulation promotes it. Finally, the effects of fixed costs on the equilibrium number of firms in the corresponding industry are captured. Source

Li M.,South China Agricultural University
Wei sheng yan jiu = Journal of hygiene research | Year: 2012

To determine whether daily multivitamins/minerals supplement can improve nutrient status, plasma, antioxidant enzymes activity and total antioxidant capacity in healthy adults. One hundred and fifty-one healthy adults living in a normal lifestyle with a mean age of 28 (20 - 50) years were recruited from Guangzhou. The subjects were divided into the supplement group and the control ineral supplements. One hundred and fifty-one healthy adults living in a normal lifestyle with a mean age of 28 (20 - 50) years were recruited from Guangzhou. The subjects were divided into the supplement group and the control group carefully matched with age and gender. Supplement pellets (consisted of multivitamins/minerals, including VitA, VitC, VitE,Ca, Zn, Fe, Se, etc.) and placebo pellets (consisted of only dextrin with the same color, shape and size as the supplement pellets) were administrated in a double-blinded manner for 8 week. The nutrients intake data of the research subjects were collected daily by a 24-hour dietary recall method. Blood samples were collected at the beginning and the end of the intervention period for determining the nutritional status, the activities of antioxidant enzymes and the products of oxidative damage. The dietary intake of nutrients was insufficient in these subjects. The levels of plasma VitC, alpha-tocopherol, beta-carotene, Zn, Fe and Se in the supplement group were increased in comparison with the control group by 46%, 28%, 116%, 7%, 30% and 28% respectively (P < 0.05), indicating that the nutritional status regarding antioxidant nutrients had largely been improved. But levels of plasma gamma-tocopherol were decreased by 25% in comparison with the control group (P < 0.05). The activities of GPX, CAT and T-AOC were increased in comparison with the control group and before the supplementation (P < 0.05), while the activities of SOD and the level of 8-isoprostanes remained steady. Supplementation of multiple micronutrients could effectively increase the levels of plasma VitC, alpha-tocopherol, beta-carotene, Zn, Fe and Se and the activities of GPX, CAT and T-AOC. Source