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Search Results: 1 - 10 of 51278 matches for " Yulin WEI "
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A MAC Scheme with QoS Guarantee for MANETs  [PDF]
Yanbin YANG, Yulin WEI
Int'l J. of Communications, Network and System Sciences (IJCNS) , 2009, DOI: 10.4236/ijcns.2009.28088
Abstract: IEEE 802.11 distributed coordination function (DCF) can alleviate the collision and hidden station problem, but it doesn’t differentiate traffic categories (TC). Therefore, it can’t provide sufficient QoS support for different traffic categories. Recently, a new contention-based enhanced distributed channel access (EDCA) scheme was proposed which provides a probabilistic QoS support. In this paper, an adaptive EDCA scheme with QoS guarantee for mobile ad hoc networks (MANETs) is proposed. In this scheme, the EDCA scheme and the token bucket algorithm (TBA) are combined to adjust the contention window (CW). Our scheme provides the traffic differentiation.
Oversea Background Executive, Risk-Taking and Corporate Performance  [PDF]
Yulin Guo
Modern Economy (ME) , 2018, DOI: 10.4236/me.2018.912139
Abstract: Overseas background executives are becoming more and more important to enterprises. By analyzing the data of A-share listed companies in China from 2011 to 2017, this paper finds that the existence of overseas background executives is conducive to the improvement of corporate performance. And senior managers with overseas working experience and core managers with overseas experience in enterprises can play a more important role. At the same time, the study shows that risk-taking plays a mediating role in the impact of overseas executives on corporate performance. And only when the external institutional environment is good, can overseas executives play their role.
Transcriptome Analysis of Yellow Horn (Xanthoceras sorbifolia Bunge): A Potential Oil-Rich Seed Tree for Biodiesel in China
Yulin Liu, Zhedong Huang, Yan Ao, Wei Li, Zhixiang Zhang
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0074441
Abstract: Background Yellow horn (Xanthoceras sorbifolia Bunge) is an oil-rich seed shrub that grows well in cold, barren environments and has great potential for biodiesel production in China. However, the limited genetic data means that little information about the key genes involved in oil biosynthesis is available, which limits further improvement of this species. In this study, we describe sequencing and de novo transcriptome assembly to produce the first comprehensive and integrated genomic resource for yellow horn and identify the pathways and key genes related to oil accumulation. In addition, potential molecular markers were identified and compiled. Methodology/Principal Findings Total RNA was isolated from 30 plants from two regions, including buds, leaves, flowers and seeds. Equal quantities of RNA from these tissues were pooled to construct a cDNA library for 454 pyrosequencing. A total of 1,147,624 high-quality reads with total and average lengths of 530.6 Mb and 462 bp, respectively, were generated. These reads were assembled into 51,867 unigenes, corresponding to a total of 36.1 Mb with a mean length, N50 and median of 696, 928 and 570 bp, respectively. Of the unigenes, 17,541 (33.82%) were unmatched in any public protein databases. We identified 281 unigenes that may be involved in de novo fatty acid (FA) and triacylglycerol (TAG) biosynthesis and metabolism. Furthermore, 6,707 SSRs, 16,925 SNPs and 6,201 InDels with high-confidence were also identified in this study. Conclusions This transcriptome represents a new functional genomics resource and a foundation for further studies on the metabolic engineering of yellow horn to increase oil content and modify oil composition. The potential molecular markers identified in this study provide a basis for polymorphism analysis of Xanthoceras, and even Sapindaceae; they will also accelerate the process of breeding new varieties with better agronomic characteristics.
Tris-(2, 3-dibromopropyl) Isocyanurate Induced Oxidative Stress in the Human Neuronal Cell Lines and in Rat Brains
Tris-(2, 3-dibromopropyl) Isocyanurate Induced Oxidative Stress in the Human Neuronal Cell Lines and in Rat Brains

Wei Feng,Yu Li,Jing Zhang,Xuefei Lyu,Yulin Deng
- , 2018, DOI: 10.15918/j.jbit1004-0579.17074
Abstract: Tris-(2, 3-dibromopropyl) isocyanurate (TBC) is a heterocyclic hexabrominated additive flame retardant, which is bio-accumulative, and can cause reproductive, endocrine disrupting, and neurotoxic effects. The present study was aimed at further evaluating the oxidative stress induced by TBC in the human neuronal cells and in rat brains. The results demonstrated that TBC caused apop-tosis of U251 and SH-SY5Y cells in a dose-and time-dependent manner and that U251 cells were more sensitive to TBC than that of SH-SY5Y cells. Meanwhile, 1 μg/mL of TBC can significantly in-duce the production of MDA in U251 cells, indicating that oxidative stress occurred after TBC short-term exposure (24 h). Similarly, in vivo administration of 0.5 mg/kg of TBC in rats for 7 days led to low growth rates and a significant increase of reactive oxygen species (ROS) and nitrogen species (RNS) in the brains. However, enzymes related to antioxidation, total superoxide dismutase (T-SOD) and reduced glutathione (GSH), were not affected obviously. This might indicate that 7-day exposure was not long enough to weaken antioxidant defence in the brains. Altogether, the results indicated that oxidative stress was induced by short-time TBC exposure.
Tris-(2, 3-dibromopropyl) isocyanurate (TBC) is a heterocyclic hexabrominated additive flame retardant, which is bio-accumulative, and can cause reproductive, endocrine disrupting, and neurotoxic effects. The present study was aimed at further evaluating the oxidative stress induced by TBC in the human neuronal cells and in rat brains. The results demonstrated that TBC caused apop-tosis of U251 and SH-SY5Y cells in a dose-and time-dependent manner and that U251 cells were more sensitive to TBC than that of SH-SY5Y cells. Meanwhile, 1 μg/mL of TBC can significantly in-duce the production of MDA in U251 cells, indicating that oxidative stress occurred after TBC short-term exposure (24 h). Similarly, in vivo administration of 0.5 mg/kg of TBC in rats for 7 days led to low growth rates and a significant increase of reactive oxygen species (ROS) and nitrogen species (RNS) in the brains. However, enzymes related to antioxidation, total superoxide dismutase (T-SOD) and reduced glutathione (GSH), were not affected obviously. This might indicate that 7-day exposure was not long enough to weaken antioxidant defence in the brains. Altogether, the results indicated that oxidative stress was induced by short-time TBC exposure.
Development and Validation of a HPLC Method for Determination of Flavone Glycoside-Camellianin B in Cephalotaxus Sinensis
Development and Validation of a HPLC Method for Determination of Flavone Glycoside-Camellianin B in Cephalotaxus Sinensis

Yongqian Zhang,Zhihui Xu,Chao Wei,Yan Chen,Yulin Deng
- , 2017, DOI: 10.15918/j.jbit1004-0579.201726.0119
Abstract: A simple, rapid and sensitive method for the quantification of camellianin B in Cephalotaxus sinensis (C. sinensis) a natural plant with anti-hyperglycemic effect, was developed and validated by reversed phase liquid chromatography. Chromatographic separation was achieved on a C18 column and an isocratic elution was carried out at a flow-rate of 1.0 mL·min-1 with the acetonitrile-water containing 0.1% formic acid (19:81, v/v). The detection wavelength was set at 330 nm. The calibration curve was linear over the concentration range of 0.25-50 μg·mL-1 with correlation coefficients larger than 0.999 5. The limit of detection and limit of quantification were 0.09 μg·mL-1and 0.25 μg·mL-1, respectively. The precisions and accuracy for all samples were acceptable. The validated method has been successfully applied for the quantification of camellianin B in C. sinensis harvested in different months and may also be used as the quality evaluation of this herb medicine.
A simple, rapid and sensitive method for the quantification of camellianin B in Cephalotaxus sinensis (C. sinensis) a natural plant with anti-hyperglycemic effect, was developed and validated by reversed phase liquid chromatography. Chromatographic separation was achieved on a C18 column and an isocratic elution was carried out at a flow-rate of 1.0 mL·min-1 with the acetonitrile-water containing 0.1% formic acid (19:81, v/v). The detection wavelength was set at 330 nm. The calibration curve was linear over the concentration range of 0.25-50 μg·mL-1 with correlation coefficients larger than 0.999 5. The limit of detection and limit of quantification were 0.09 μg·mL-1and 0.25 μg·mL-1, respectively. The precisions and accuracy for all samples were acceptable. The validated method has been successfully applied for the quantification of camellianin B in C. sinensis harvested in different months and may also be used as the quality evaluation of this herb medicine.
Insecticide-Mediated Apparent Displacement between Two Invasive Species of Leafminer Fly
Yulin Gao, Stuart R. Reitz, Qingbo Wei, Wenyan Yu, Zhongren Lei
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0036622
Abstract: Background Closely related invasive species may often displace one another, but it is often difficult to determine mechanisms because of the historical nature of these events. The leafmining flies Liriomyza sativae and Liriomyza trifolii have become serious invasive agricultural pests throughout the world. Where both species have invaded the same region, one predominates over the other. Although L. sativae invaded Hainan Island of China first, it recently has been displaced by the newly invasive L. trifolii. We hypothesized that differential susceptibilities to insecticides could be causing this demographic shift. Methodology/Principal Findings Avermectin and cyromazine are the most commonly used insecticides to manage leafminers, with laboratory bioassays demonstrating that L. trifolii is significantly less susceptible to these key insecticides than is L. sativae. In trials where similar numbers of larvae of both species infested plants, which subsequently were treated with the insecticides, the eclosing adults were predominately L. trifolii, yet similar numbers of adults of both species eclosed from control plants. The species composition was then surveyed in two regions where L. trifolii has just begun to invade and both species are still common. In field trials, both species occurred in similar proportions before insecticide treatments began. Following applications of avermectin and cyromazine, almost all eclosing adults were L. trifolii in those treatment plots. In control plots, similar numbers of adults of the two species eclosed, lending further credence to the hypothesis that differential insecticide susceptibilities could be driving the ongoing displacement of L. sativae by L. trifolii. Conclusions/Significance Our results show that differential insecticide susceptibility can lead to rapid shifts in the demographics of pest complexes. Thus, successful pest management requires the identification of pest species to understand the outcome of insecticide applications. These results further demonstrate the importance of considering anthropogenic factors in the outcome of interspecific interactions.
Peak compression technique in high-performance liquid chromatography
YuXia Wei,Lin Wang,ShengYuan Xiao,Hong Qing,Yong Zhu,GaoFei Hu,YuLin Deng
Chinese Science Bulletin , 2009, DOI: 10.1007/s11434-009-0381-2
Abstract: Peak compression technique based on the difference of the solute migration velocity in two different mobile phases was described theoretically and confirmed using benzaldehyde and 4- hydroxyquinoline (4-HQ) as model compounds. After peak compression, the peak compression factors (the ratio of peak width at half-height under non-compression and that under compression condition) of benzaldehyde and 4-HQ were 0.19 and 0.13, respectively. By this application of the peak compression technique to the mixture, both enhanced peak height and good separation were obtained in one run cycle. This peak compression technique was introduced to determine benzaldehyde from semicarbazide-sensitive amine oxidase-catalyzed enzymetic reaction in order to illustrate the applicability of this technique to the real sample. As a result, the peak was compressed effectively, and 4.94-fold, 19.3-fold and 5.74-fold enhancement in peak height, plate number and signal to noise ratio were also achieved, respectively.
Hardware Optimization Technique of Full-Customized HW/SW Co-Design
全定制软/硬件协同设计中的硬件优化技术(英文)

Tang Lei,Wei Shaojun,Qiu Yulin,
汤磊
,魏少军,仇玉林

半导体学报 , 2002,
Abstract: The hardware optimization technique of mono similarity system generation is presented based on hardware/software(HW/SW) co design.First,the coarse structure of sub graphs' matching based on full customized HW/SW co design is put forward.Then,a universal sub graphs' combination method is discussed.Next,a more advanced vertexes' compression algorithm based on sub graphs' combination method is discussed with great emphasis.Experiments are done successfully with perfect results verifying all the formulas and the methods above.
Local Crop Planting Systems Enhance Insecticide-Mediated Displacement of Two Invasive Leafminer Fly
Yulin Gao, Stuart R. Reitz, Qingbo Wei, Wenyan Yu, Zhi Zhang, Zhongren Lei
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0092625
Abstract: Liriomyza sativae and L. trifolii are highly invasive leafminer pests of vegetable crops that have invaded southern China in recent years. Liriomyza sativae was the first of these species to invade China, but it is now being displaced by L. trifolii. The rate and extent of this displacement vary across southern China. In Hainan, monocultures of highly valuable cowpea are planted and treated extensively with insecticides in attempts to control leafminer damage. In Guangdong, cowpea fields are interspersed with other less valuable crops, such as towel gourd (Luffa cylindrica), which receive significantly fewer insecticide applications than cowpea. To determine how differences in cropping systems influence the Liriomyza species composition, we conducted field trials in 2011 and 2012 in Guangdong where both species were present. We replicated conditions in Hainan by planting cowpea monocultures that were isolated from other agricultural fields, and we replicated conditions in Guangdong by planting cowpea in a mixed crop environment with towel gourd planted in neighboring plots. We then compared leafminer populations in cowpea treated with the insecticide avermectin and untreated cowpea. We also monitored leafminer populations in the untreated towel gourd. Untreated cowpea and towel gourd had comparatively low proportions of L. trifolii, which remained relatively stable over the course of each season. Avermectin applications led to increases in the proportions of L. trifolii, and after three weekly applications populations were >95% L. trifolii in both crop systems. However, the rate of change and persistence of L. trifolii in the mixed crop system were less than in the monocrop. These results indicate that L. trifolii is much less susceptible to avermectin than is L. sativae. Further, L. sativae was able to persist in the untreated towel gourd, which probably enabled it to recolonize treated cowpea.
Positive Solutions for (k, n ? k) Conjugate Multipoint Boundary Value Problems in Banach Spaces
Yulin Zhao
International Journal of Mathematics and Mathematical Sciences , 2012, DOI: 10.1155/2012/727468
Abstract: By means of the fixed point index theory of strict-set contraction operator, we study the existence of positive solutions for the multipoint singular boundary value problem , , , , , , , in a real Banach space , where is the zero element of As an application, we give two examples to demonstrate our results. 1. Introduction The theory of ordinary differential equations in Banach spaces has become a new important branch (see, e.g., [1–13] and the references cited therein). In 1988, Guo and Lakshmikantham [4] discussed multiple solutions for two-point boundary value problems of second-order ordinary differential equations in Banach spaces. In [7], Guo obtained the existence of positive solutions for a boundary value problem of nth-order nonlinear impulsive integrodifferential equations in a Banach space by means of fixed point index theory and fixed point theory of completely continuous operators, respectively. Liu et al. in [6] obtained the existence of unbounded nonnegative solutions of a boundary value problem for nth-order impulsive integrodifferential equations on an infinite interval in Banach spaces by means of the Mddotoch fixed point theory in a Banach space. Zhang et al. in [9] dealt with the existence, nonexistence, and multiplicity of positive solutions for a class of nonlinear three-point boundary value problems of nth-order differential equations in Banach spaces. Zhao and Chen in [8, 12] investigated the existence of at least triple positive solutions for nonlinear boundary value problem by upper and low solution methods. In this paper, the author considers the existence of positive solutions of the following higher-order conjugate multipoint boundary value problems (BVPs): in a real Banach space , where is the zero element of . ? is continuous and allowed to be singular at and . In scalar space, because of the widely applied background in mechanics and engineering, the nonlinear higher-order boundary value problems have received much attention (see Chyan and Henderson [Appl. Math. Letters 15 (2002) 767–774]). In [14], Eloe and Ahmad had solved successfully the existence of positive solution to the following nth-order boundary value problems: Recently, the existence of solutions and positive solutions of nonlinear focal boundary value problem and its special cases has been studied by many authors (see, e.g., [15–23]). By using the Krasnoselskii fixed point theorem, Eloe and Henderson in [15], Agarwal and O'Regan in [16], and Kong and Wang in [20] have established the existence of solutions for following the conjugate boundary value problem:
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