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Search Results: 1 - 10 of 120086 matches for " Guirong Wang "
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Positive Periodic Solutions for Neutral Delay Ratio-Dependent Predator-Prey Model with Holling-Tanner Functional Response
Guirong Liu,Sanhu Wang,Jurang Yan
International Journal of Mathematics and Mathematical Sciences , 2011, DOI: 10.1155/2011/376862
Abstract: By using a continuation theorem based on coincidence degree theory, we establish some easily verifiable criteria for the existence of positive periodic solutions for neutral delay ratio-dependent predator-prey model with Holling-Tanner functional response , . 1. Introduction The dynamic relationship between the predator and the prey has long been and will continue to be one of the dominant themes in population dynamics due to its universal existence and importance in nature [1]. In order to precisely describe the real ecological interactions between species such as mite and spider mite, lynx and hare, and sparrow and sparrow hawk, described by Tanner [2] and Wollkind et al. [3], May [4] developed the Holling-Tanner prey-predator model In system (1.1), and stand for prey and predator density at time . , , , , , are positive constants that stand for prey intrinsic growth rate, carrying capacity, capturing rate, half-capturing saturation constant, predator intrinsic growth rate, and conversion rate of prey into predators biomass, respectively. Nowadays attention have been paid by many authors to Holling-Tanner predator-prey model (see [5–7]). Recently, there is a growing explicit biological and physiological evidence [8–10] that in many situations, especially when predators have to search for food (and, therefore, have to share or compete for food), a more suitable general predator-prey theory should be based on the so-called ratio-dependent theory, which can be roughly stated as that the per capita predator growth rate should be a function of the ratio of prey to predator abundance and so should be the so-called ratio-dependent functional response. This is strongly supported by numerous field and laboratory experiments and observations [11, 12]. Generally, a ratio-dependent Holling-Tanner predator-prey model takes the form of Liang and Pan [13] obtained results for the global stability of the positive equilibrium of (1.2). However, time delays of one type or another have been incorporated into biological models by many researchers; we refer to the monographs of Cushing [14], Gopalsamy [15], Kuang [16], and MacDonald [17] for general delayed biological systems. Time delay due to gestation is a common example, because generally the consumption of prey by the predator throughout its past history governs the present birth rate of the predator. Therefore, more realistic models of population interactions should take into account the effect of time delays. Recently, Saha and Chakrabarti [18] considered the following delayed ratio-dependent Holling-Tanner
Effect of Electroplating Waste water on Immune Function in Kunming Mice  [PDF]
Zongqi Ma, Guirong Wang, Yufen Tian, Deli Xu, Xiaofeng Miao, Ying Zhang, Jiao Meng, Hong Ni, Weiwei Sun
Natural Science (NS) , 2016, DOI: 10.4236/ns.2016.87036
Abstract: Electroplating waste water is considered to be harmful to health of animals. In the present study, we tested the hypothesis that electroplating waste water would suppress immune functions in Kunming mice. Twenty-six mice were randomly divided into the control group (n = 13) and the experimental group (n = 13), in which the latter drank electroplating waste water. We found that body mass and most organ wet masses (heart, lungs, liver, kidneys, stomach, caecum, colon, testes, epididymis, seminal vesicals) were not influenced by electroplating waste water. However, stomach with its content, small intestine, small intestine with its contents and colon with its contents were higher in the experimental group than in the control group. As expected, phytohaemagglutinin (PHA) response indicative of cellular immunity was suppressed by electroplating waste water. White blood cells, thymus and spleen mass were all not response to electroplating waste water. Taken together, electroplating waste water had different effects on distinct components of immune system in Kunming mice.
Candidate Olfaction Genes Identified within the Helicoverpa armigera Antennal Transcriptome
Yang Liu, Shaohua Gu, Yongjun Zhang, Yuyuan Guo, Guirong Wang
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0048260
Abstract: Antennal olfaction is extremely important for insect survival, mediating key behaviors such as host preference, mate choice, and oviposition site selection. Multiple antennal proteins are involved in olfactory signal transduction pathways. Of these, odorant receptors (ORs) and ionotropic receptors (IRs) confer specificity on olfactory sensory neuron responses. In this study, we identified the olfactory gene repertoire of the economically important agricultural pest moth, Helicoverpa armigera, by assembling the adult male and female antennal transcriptomes. Within the male and female antennal transcriptomes we identified a total of 47 OR candidate genes containing 6 pheromone receptor candidates. Additionally, 12 IR genes as well as 26 odorant-binding proteins and 12 chemosensory proteins were annotated. Our results allow a systematic functional analysis across much of conventional ORs repertoire and newly reported IRs mediating the key olfaction-mediated behaviors of H. armigera.
Gene cloning and expression of cadherin in midgut of Helicoverpa armigera and its Cry1A binding region
Guirong Wang,Kongming Wu,Gemei Liang,Yuyuan Guo
Science China Life Sciences , 2005, DOI: 10.1360/03yc0273
Abstract: Cadherins belong to one of the families of animal glycoproteins responsible for calcium-dependent cell-cell adhesion. Recent literatures showed that the cadherin-like in midgut of several insects served as the receptor of Bt toxin Cry1A and the variation of cadherin-like is related to insect’s resistance to Cry1A. The full-length cDNA encoding cadherin-like of Helicoverpa armigera is cloned by degenerate PCR and RACE techniques and the gene was designated as BtR-harm, which is 5581 bp in full-length, encoding 1730 amino acid residues (BtR-harm was deposited in GenBank and the accession number is AF519180). Its predicted molecular weight and isoelectric point were 195.39 kDa and 4.23, respectively. The inferred amino acid sequence includes a signal sequence, 11 cadherin repeats, a membrane-proximal region, a transmembrane region and a cytoplasmic region. Sequence analysis indicated that the deduced protein sequence was most similar to the cadherin-like from Heliothis virescens with 84.2% identity and highly similar to three other lepidopteran cadherin from Bombyx mori, Manduca sexta and Pectinophora gossypiella, with the sequence identities of 60.3.6%, 57.5% and 51.0%, respectively. The cDNA encoding cadherin gene was expressed successfully in E. coli and the recombinant proteins can bind with Cry1Ac. Truncation analysis and binding experiment of BtR-harm revealed that the Cry1A binding region was a contiguous 244-amino acid sequence, which located between amino acid 1217 and 1461. Semi-quantitative RT-PCR analysis showed that BtR-harm was highly expressed in midgut of H. armigera, very low expressed in foregut and hindgut and was not expressed in other tissues. After H. armigera producing resistance to Cry1Ac, the expression quantity of BtR-harm significantly decreased in midgut of H. armigera. It is the first confirmation that BtR-harm can function as receptor of Cry1Ac in H. armigera and the binding region was located on a contiguous 244 amino acid sequence, suggesting that the decrease of expression quantity of BtR-harm is one of the main reasons for H. armigera resistance to Cry1Ac.
Motifs within the CA-repeat-rich region of Surfactant Protein B (SFTPB) intron 4 differentially affect mRNA splicing
Wenjun Yang,Lan Ni,Patricia Silveyra,Guirong Wang
Journal of Molecular Biochemistry , 2013,
Abstract: The first half of the surfactant protein B (SP-B) gene intron 4 is a CA-repeat-rich region that contains 11 motifs. To study the role of this region on SP-B mRNA splicing, minigenes were generated by systematic removal of motifs from either the 5’ or 3’ end. These were transfected in CHO cells to study their splicing efficiency. The latter was determined as the ratio of completely to incompletely spliced SP-B RNA. Our results indicate that SP-B intron 4 motifs differentially affect splicing. Motifs 8 and 9 significantly enhanced and reduced splicing of intron 4, respectively. RNA mobility shift assays performed with a Motif 8 sequence that contains a CAUC cis-element and cell extracts resulted in a RNA:protein shift that was lost upon mutation of the element. Furthermore, in silico analysis of mRNA secondary structure stability for minigenes with and without motif 8 indicated a correlation between mRNA stability and splicing ratio. We conclude that differential loss of specific intron 4 motifs results in one or more of the following: a) altered splicing, b) differences in RNA stability and c)changes in secondary structure. These, in turn, may affect SP-B content in lung health or disease.
Identification of Immunity-Related Genes in Ostrinia furnacalis against Entomopathogenic Fungi by RNA-Seq Analysis
Yang Liu, Dongxu Shen, Fan Zhou, Guirong Wang, Chunju An
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0086436
Abstract: Background The Asian corn borer (Ostrinia furnacalis (Guenée)) is one of the most serious corn pests in Asia. Control of this pest with entomopathogenic fungus Beauveria bassiana has been proposed. However, the molecular mechanisms involved in the interactions between O. furnacalis and B. bassiana are unclear, especially under the conditions that the genomic information of O. furnacalis is currently unavailable. So we sequenced and characterized the transcriptome of O. furnacalis larvae infected by B. bassiana with special emphasis on immunity-related genes. Methodology/Principal Findings Illumina Hiseq2000 was used to sequence 4.64 and 4.72 Gb of the transcriptome from water-injected and B. bassiana-injected O. furnacalis larvae, respectively. De novo assembly generated 62,382 unigenes with mean length of 729 nt. All unigenes were searched against Nt, Nr, Swiss-Prot, COG, and KEGG databases for annotations using BLASTN or BLASTX algorithm with an E-value cut-off of 10?5. A total of 35,700 (57.2%) unigenes were annotated to at least one database. Pairwise comparisons resulted in 13,890 differentially expressed genes, with 5,843 up-regulated and 8,047 down-regulated. Based on sequence similarity to homologs known to participate in immune responses, we totally identified 190 potential immunity-related unigenes. They encode 45 pattern recognition proteins, 33 modulation proteins involved in the prophenoloxidase activation cascade, 46 signal transduction molecules, and 66 immune responsive effectors, respectively. The obtained transcriptome contains putative orthologs for nearly all components of the Toll, Imd, and JAK/STAT pathways. We randomly selected 24 immunity-related unigenes and investigated their expression profiles using quantitative RT-PCR assay. The results revealed variant expression patterns in response to the infection of B. bassiana. Conclusions/Significance This study provides the comprehensive sequence resource and expression profiles of the immunity-related genes of O. furnacalis. The obtained data gives an insight into better understanding the molecular mechanisms of innate immune processes in O. furnacalis larvae against B. bassiana.
Functional Specificity of Sex Pheromone Receptors in the Cotton Bollworm Helicoverpa armigera
Yang Liu, Chengcheng Liu, Kejian Lin, Guirong Wang
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0062094
Abstract: Male moths can accurately perceive the sex pheromone emitted from conspecific females by their highly accurate and specific olfactory sensory system. Pheromone receptors are of special importance in moth pheromone reception because of their central role in chemosensory signal transduction processes that occur in olfactory receptor neurons in the male antennae. There are a number of pheromone receptor genes have been cloned, however, only a few have been functionally characterized. Here we cloned six full-length pheromone receptor genes from Helicoverpa armigera male antennae. Real-time PCR showing all genes exhibited male-biased expression in adult antennae. Functional analyses of the six pheromone receptor genes were then conducted in the heterologous expression system of Xenopus oocytes. HarmOR13 was found to be a specific receptor for the major sex pheromone component Z11-16:Ald. HarmOR6 was equally tuned to both of Z9-16: Ald and Z9-14: Ald. HarmOR16 was sensitively tuned to Z11-16: OH. HarmOR11, HarmOR14 and HarmOR15 failed to respond to the tested candidate pheromone compounds. Our experiments elucidated the functions of some pheromone receptor genes of H. armigera. These advances may provide remarkable evidence for intraspecific mating choice and speciation extension in moths at molecular level.
Screening of Highly Expressed CPEΔN Lung Cancer H1299 Cells
Jing SUN, Guirong ZHANG, Hongyue WANG, Hui SHEN
- , 2015, DOI: : 10.3779/j.issn.1009-3419.2015.06.03
Abstract: Background and objective The N-terminal truncated carboxypeptidase E (CPEΔN) protein is a novel biomarker of tumor metastasis. This study screened the H1299 cell line with a highly expressed CPEΔN gene for in vivo imaging experiment. Methods Human CPEΔN gene was cloned into the luciferase lentiviral vector. H1299 cells transduced with CPEΔN or control lentiviral vectors were selected with 2 μg/mL puromycin. The expression of CPEΔN was identified through Western blot analysis, and luciferase activity was measured using luciferase reporters. Results The human CPEΔN lentiviral expression vector was successfully constructed. The transfection rate of H1299 cells by the lentivirus achieved 80%, with an infection multiplicity of 20. The H1299 cell line with high CPEΔN (H1299-CPEΔN) expression was established, with an increase in CPEΔN expression by four times compared with the control lentivirus-transfected H1299 cell line (H1299-control). As H1299-CPEΔN and H1299-control can effectively decompose luciferase substrates, they can be applied in in vivo imaging. Conclusion H1299-CPEΔN and H1299-control can be used in in vivo imaging experiment for further research on molecular mechanisms and signal transduction to elucidate the role of CPEΔN in lung cancer metastasis.
Distinct Olfactory Signaling Mechanisms in the Malaria Vector Mosquito Anopheles gambiae
Chao Liu,R. Jason Pitts,Jonathan D. Bohbot,Patrick L. Jones,Guirong Wang,Laurence J. Zwiebel
PLOS Biology , 2012, DOI: 10.1371/journal.pbio.1000467
Abstract: Anopheles gambiae is the principal Afrotropical vector for human malaria, in which olfaction mediates a wide range of both adult and larval behaviors. Indeed, mosquitoes depend on the ability to respond to chemical cues for feeding, host preference, and mate location/selection. Building upon previous work that has characterized a large family of An. gambiae odorant receptors (AgORs), we now use behavioral analyses and gene silencing to examine directly the role of AgORs, as well as a newly identified family of candidate chemosensory genes, the An. gambiae variant ionotropic receptors (AgIRs), in the larval olfactory system. Our results validate previous studies that directly implicate specific AgORs in behavioral responses to DEET as well as other odorants and reveal the existence of at least two distinct olfactory signaling pathways that are active in An. gambiae. One system depends directly on AgORs; the other is AgOR-independent and requires the expression and activity of AgIRs. In addition to clarifying the mechanistic basis for olfaction in this system, these advances may ultimately enhance the development of vector control strategies, targeting olfactory pathways in mosquitoes to reduce the catastrophic effects of malaria and other mosquito-borne diseases.

Chen Changyan,Wang Guirong,

岩石力学与工程学报 , 2002,
Abstract: A large number of rock mass quality classification systems have been put forward in the world. Recent advances in this field at home and abroad are reviewed systemically in this paper. The relationship between rock mass structure, rock mass quality and its classification is summarized. Finally,a relation of interrelation,comparison and conversion among the main rock mass quality classification systems are proposed.
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