40 resultados para Person-Organization Fit


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We studied social organization, behavior, and range use of the Yunnan snub-nosed monkey (Rhinopithecus bieti) at Wuyapiya (99 degrees 12'E, 28 degrees 30'N, the People's Republic of China) over 12 months between May 1992 and June 1994. The Wuyapiya band contained greater than or equal to 175 members and had two levels of social organization. At one level, the monkeys formed multifemale, one-male units (OMUs) similar to those of many other colobines. At another level, 15 to 18 OMUs traveled together in a cohesive band. Unlike the bands of other species of Rhinopithecus, the Wuyapiya band of R. bieti did not show seasonal fission-fusion, although some social behavior, such as male-male aggression, was seasonal. With regard to range use, the Wuyapiya band had a large home range and long daily travel distances compared with other colobines. Minimum range size in 1 year at Wuyapiya is 16.25 km(2), although there is no asymptote for range size as a function of observation time. Range size for the Wuyapiya band is 25.25 km(2) over the 2-year study and appeared to cover 100 km(2) between 1985 and 1994. The primary food of R. bieti at Wuyapiya is lichens, which are ubiquitous in fir frees. The multitiered social organization of R. bieti appears to result from the interaction of food resource characters with the forces of mate competition, with band sizes based on female responses to the spatial and temporal characteristics of lichens and subdivisions within bands based on male competition for mates.

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Data on social organization of two bands of black-and-white snub-nosed monkeys (Rhinopithecus bieti) 14 were collected when the monkeys were crossing an open spot at Nanren and Bamei (northwest of Yunnan, China) using a sampling rule where individuals wit

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To investigate germline development and germ cell specification, we identified a Dazl homolog (CagDazl) from gynogenetic gibel carp (Carassius auratus gibelio). Its cDNA sequence and BAC clone sequence analyses revealed the genomic organization conservation and conserved synteny of the Dazl family members and their neighborhood genes among vertebrates, especially in fish. Moreover, a polyclonal antibody specific to CagDazl was produced and used to examine its expression and distribution throughout germline development at protein level. Firstly, ovary-specific expression pattern of CagDazl was confirmed in adult tissues by RT-PCR and Western blot. In addition, in situ hybridization and immunofluorescence localization demonstrated its specific expression in germ cells, and both its transcript and protein were localized to germ plasm. Then, co-localization of CagDazl and mitochondrial cloud was found, confirming that CagDazl transcript and its protein are germ plasm component and move via METRO pathway during oogenesis. Furthermore, the CagDazl is abundant and continuous throughout germline development and germ cell specification including primordial germ cell (PGC) formation, oogonium differentiation, oocyte development, and embryogenesis, and the dynamic distribution occurs at different development stages. The data suggest that maternal CagDazl might play an important role in gibel carp PGC formation. Therefore, CagDazl is a useful and specific marker for tracing germ plasm and germ cell development in the gynogenetic gibel carp. In addition, in comparison with previous studies in sexual reproduction species, the continuous and dynamic distribution of CagDazl protein in the germ plasm throughout the life cycle seems to have significant implication in sex evolution of vertebrates. J. Exp. Zool. (Mol. Deu. Euol.) 312B:855-871, 2009. (C) 2009 Wiley-Liss, Inc.

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Toll-like receptor 3 (TLR3) participates in the innate immune response by recognizing viral pathogens. To investigate grass carp immune system responding to GCRV (grass carp reovirus) infection, the full-length cDNA sequence and genomic organization of grass carp TLR3 (CiTLR3) was identified and characterized. The full-length genome sequence of CiTLR3 is composed of 5668 nucleotides, including five exons and four introns. The full-length of CiTLR3 cDNA is 3681 bp in length and encodes a polypeptide of 904 amino acids with an estimated molecular mass of 102,765 Da and a predicted isoelectric point of 8.35. Analysis of the deduced amino acid sequence indicated that CiTLR3 has four main structural domains, including a signal peptide sequence, 14 LRR (leucine-rich repeat) motifs, a transmembrane region and a TIR (Toll/interleukin-1 receptor) domain. It is most similar to the crucian carp (Carassius auratus) TLR3 amino acid sequence with an identity of 99%. Quantitative RT-PCR analysis showed that CiTLR3 transcripts were significantly up-regulated starting at day 1 and continued through day 7 following GCRV infection (P < 0.05). These data implied that CiTLR3 is involved in antiviral defense, provide molecular and functional information for grass carp TLR3, and implicate their role in mediating immune protection against grass carp viral diseases. (C) 2009 Elsevier Ltd. All rights reserved.

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Natural killer (NK) cell enhancing factor (NKEF) belongs to the newly defined peroxiredoxin (Prx) family. Its functions are to enhance NK cell cytotoxicity and to protect DNA and proteins from oxidative damage. In this study, a partial cDNA sequence of carp NKEF-B was isolated from thymus cDNA library. Subsequently, the full-length cDNA of carp NKEF-B was obtained by means of 3' and 5' RACE, respectively. The full-length cDNA of carp NKEF-B was 1022 bp, consisting of a 73 bp 5'-terminal untranslated region (UTR), a 355 bp T-terminal UTR, and a 594 bp open reading frame coding for a protein of 197 amino acids. Carp NKEF-B contained two consensus Val-Cys-Pro (VCP) motifs and three consensus cysteine (Cys-51, Cys-70 and Cys-172) residues. Sequence comparison showed that the deduced amino acid sequence of carp NKEF-B had an overall similarity of 74-96% to that of other species homologues. Phylogenetic analysis revealed that carp NKEF-B forms a cluster with other known teleost NKEF-Bs. Then, by PCR we obtained a 5.1 -k long genomic DNA of carp NKEF-B containing six exons and five introns. Realtime RT-PCR results showed that carp NKEF-B gene was predominantly detected in kidney and head kidney under un-infected conditions. Whereas under SVCV-infection condition, the expression of NKEF-B gene was significantly increased in blood cells, gill, intestine and spleen, but maintained in liver, and decreased significantly in kidney and head kidney. Finally, the rNKEF-B was constructed and expressed in Escherichia coli. By using an antibody against carp rNKEF-B, immunohistochemical study further indicated that NKEF-B positive cells are mainly some RBCs and a few epithelial cells in gill and intestine, and that under SVCV-infection condition, these positive cells or positive products in their cytoplasm were mainly increased in gill and spleen sections of carp. The results obtained in the present study will help to understand the function of NKEF-B in teleost innate immunity. (C) 2008 Elsevier Ltd. All rights reserved.

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Hepatotoxic microcystins (MCs) are the most commonly reported cyanotoxins in eutrophic freshwaters. In 1996, human intoxications by MCs caused deaths of 76 patients at Caruaru dialysis centers in Brazil. So far, there have been no direct evidences of MC occurrence in human tissue in consequence of exposure to MC. In this study, we improved cleanup procedures for detecting MCs in serum sample using liquid chromatographymass spectrometry, and confirmed for the first time the presence of MCs in serum samples (average 0.39 ng/ml, which amounts to ca. 1/87 of the concentrations found in tissue samples of the Caruaru victims) of fishermen at Lake Chaohu. Daily intake by the fishermen was estimated to be in the range of 2.2-3.9 mu g MC-LReq, whereas the provisional World Health Organization tolerable daily intake (TDI) for daily lifetime exposure is 0.04 mu g/kg or 2-3 mu g per person. Moreover, statistical analysis showed closer positive relationships between MC serum concentrations and concentrations of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and lactate dehydrogenase than between the MC concentrations and other biochemical indicators. Thus, the data raise the question whether extended exposure in the range of the TDI or up to a factor of 10 above it may already lead to indication of liver damage. The results also demonstrate a risk of health effects from chronic exposure to MCs at least for populations with high levels of exposure, like these fishermen.

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SLP-76 is an important member of the SLP-76 family of adapters, and it plays a key role in TCR signaling and T cell function. Partial cDNA sequence of SLP-76 of common carp (Cyprinus carpio L.) was isolated from thymus cDNA Library by the method of suppression subtractive hybridization (SSH). Subsequently, the full length cDNA of carp SLP-76 was obtained by means of 3' RACE and 5' RACE, respectively. The full Length cDNA of carp SLP-76 was 2007 bp, consisting of a T-terminal untranslated region (UTR) of 285 bp, a T-terminal. UTR of 240 bp, and an open reading frame of 1482 bp. Sequence comparison showed that the deduced amino acid sequence of carp SLP-76 had an overall similarity of 34-73% to that of other species homotogues, and it was composed of an NH2-terminal domain, a central proline-rich domain, and a C-terminal SH2 domain. Amino acid sequence analysis indicated the existence of a Gads binding site R-X-X-K, a 10-aa-long sequence which binds to the SH3 domain of LCK in vitro, and three conserved tyrosine-containing sequence in the NH2-terminal domain. Then we used PCR to obtain a genomic DNA which covers the entire coding region of carp SLP-76. In the 9.2 k-long genomic sequence, twenty one exons and twenty introns were identified. RT-PCR results showed that carp SLP-76 was expressed predominantly in hematopoietic tissues, and was upregulated in thymus tissue of four-month carp compared to one-year old carp. RT-PCR and virtual northern hybridization results showed that carp SLP-76 was also upregulated in thymus tissue of GH transgenic carp at the age of four-months. These results suggest that the expression level of SLP-76 gene may be related to thymocyte development in teleosts. (c) 2007 Published by Elsevier Ltd.

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The unusual allotetraploid form with unequal contribution of chromosome sets was discovered from the gynogenetic offspring of Carassius auratus gibelio stimulated by red common carp sperm. In this study, genomic in situ hybridization (GISH) and fluorescent in situ hybridization (FISH) with 45S rDNA probe are used. The GISH results lead to the identification of species-specific chromosomes, which permits to demonstrate the origin and genome organization in the allotetraploid form. Moreover, chromosome localization of 45S rDNA and co-localizations of 45S rDNA and Cyprinus carpio genomic DNA further confirm that one extra 45S rDNA positive chromosome in the allotetraploid form originates from the paternal haploid genome of C carpio, and other 5 45S rDNA-containing chromosomes are from the maternal genome of Carassius auratus gibelio. And, the correlation between 45 rDNA and the nucleolar organizer regions (NORs) is confirmed by silver nitrate staining. The data provide direct experiment evidence that the allotetraploid actually contains three chromosome sets of Carassius auratus gibelio and one chromosome set of C carpio, and will be a useful genetic material for both basic research and breeding practice. (c) 2006 Elsevier B.V. All rights reserved.

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Interleukin-1 beta (IL-1 beta) is one of the pivotal early response pro-inflammatory cytokines that enables organisms to respond to infection and induces a cascade of reactions leading to inflammation. In spite of its importance and two decades of studies in the mammalian species, genes encoding IL-1 beta were not identified from non-mammalian species until recently. Recent research, particularly with genomic approaches, has led to sequencing of IL-1 beta from many species. Clinical studies also Suggested IL-1 beta as an immunoreagulatory molecule potentially useful for enhancing vaccination. However, no IL-1 beta genes have been identified from channel catfish, the primary aquaculture species from the United States. In this study, we identified two distinct cDNAs encoding catfish IL-1 beta. Their encoding genes were identified, sequenced, and characterized. The catfish IL-1 beta genes were assigned to bacterial artificial chromosome (BAC) clones. Genomic studies indicated that the IL-1 beta genes were tandemly duplicated on the same chromosome. Phylogenetic analysis of various IL-1 beta genes indicated the possibility of recent species-specific gene duplications in channel catfish, and perhaps also in swine and carp. Expression analysis indicated that both IL-1 beta genes were expressed, but exhibited distinct expression profiles in various catfish tissues, and after bacterial infection with Edwardsiella ictaluri. (c) 2005 Elsevier Ltd. All rights reserved.

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A Ge/Si(0 0 1) multilayer structure is investigated by cross-sectional transmission electron microscopy, atomic force microscopy and double crystal X-lay diffraction. We find that the multilayer-structure-related satellite peaks in the rocking curve exhibit a similar nonuniform broadening and rye fit the zero-order peak with two Lorentz lineshapes. The ratio of the integrated intensity of two peaks is approximately equal with the anal ratio of the top Ge layer deposited between the areas that are and are not occupied by islands. It proves the existence of vertical-aligned island columns from the viewpoint of macroscopic dimension. (C) 2001 Elsevier Science B.V. All rights reserved.

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The initial InAs growth on InP(1 0 0) during molecular beam epitaxy has been investigated. The as-grown islands were shaped like nanowires and formed dense arrays over the entire surface in the 3-6 monolayer InAs deposition range. The wires were oriented along the [(1) over bar 1 0] direction. Transmission electron microscopy images confirm that the wires are coherently grown on the substrates. Our results suggest that the coherent wire-shaped island formation may be a possible method to fabricate self-organized InAs nanowires. (C) 1999 Elsevier Science B.V. All rights reserved.

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The mechanism of self-organization of quantum dots (QDs) during the growth of InGaAs/GaAs multilayers on GaAs (1 0 0) was investigated with cross-sectional transmission electron microscopy (XTEM), and double-crystal X-ray diffraction (DCXD). We found that the QDs spacing in the first layer can affect the vertical alignment of QDs. There seems to exist one critical lateral QD spacing, below which merging of QDs with different initial size is found to be the dominant mechanism leading to perfect vertical alignment. Once the critical value of QDs spacing is reached, the InGaAs QDs of the first layer are simply reproduced in the upper layers. The X-ray rocking curve clearly shows two sets of satellite peaks, which correspond to the QDs superlattice, and multi-quantum wells (QW) formed by the wetting layers around QDs. (C) 1999 Elsevier Science B.V. All rights reserved.

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The mechanism of self-organization of quantum dots (QDs) during the growth of InGaAs/GaAs multilayers on GaAs (1 0 0) was investigated with cross-sectional transmission electron microscopy (XTEM), and double-crystal X-ray diffraction (DCXD). We found that the QDs spacing in the first layer can affect the vertical alignment of QDs. There seems to exist one critical lateral QD spacing, below which merging of QDs with different initial size is found to be the dominant mechanism leading to perfect vertical alignment. Once the critical value of QDs spacing is reached, the InGaAs QDs of the first layer are simply reproduced in the upper layers. The X-ray rocking curve clearly shows two sets of satellite peaks, which correspond to the QDs superlattice, and multi-quantum wells (QW) formed by the wetting layers around QDs. (C) 1999 Elsevier Science B.V. All rights reserved.

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通过介绍麦克斯韦方程的离散过程 ,简单介绍了有限积分理论 ( Finite Integration Theo-ry)。该理论直接以电场强度和磁感应强度为未知量 ,采用两套互相正交的网格 ,将场矢量离散为不同网格点上的一系列分量 ,将矢量积分方程转化为一组线性方程组。通过对 SFC高频腔体模拟的实例 ,可以看出 ,此方法在腔体本征频率、Q值及腔体并联阻抗等腔体参数计算中具有叫高的精度 ,说明了基于FIT的 MAFIA程序在腔体模拟中的可靠性