9 resultados para Resident
em Chinese Academy of Sciences Institutional Repositories Grid Portal
Resumo:
Between October 1999 and April 2000, WC surveyed the waterbirds at Lake Lashihai, China. A total of 52 species were recorded, of which one species was a resident, 34 were winter visitors, and 17 were passage migrants. Species richness was highest in November. Passage migrants mainly occurred in October, November, and April, and they stayed longer at the lake during their autumn migration than during the spring migration. The seasonal distribution pattern of total numbers of all waterbirds was bimodal. One peak occurred between late December and early January, and the other in middle March. The seasonal distribution patterns of 15 common species have been classified a. bimodal, unimodal, or irregular. The numbers of five common species were variable in middle winter, and their numerical Change in contiguous weeks were more than 30%, suggesting that local movements might be frequent.
Resumo:
In five groups of seasonally provisioned Tibetan macaques (Macaca thibetana) at Mt. Emei, males were sampled for wounds as an indicator of their competition for females during about 80 days in the 1987 mating season. Quantitative data on intergroup transfer were collected in a period between June 1986 and December 1987. The young adult (YA) males, the most active age-class in mating activity and intergroup transfer, received most of the wounds. Wounds tended to appear more in the front of body for YA and subadults (SA) than they did for middle-old aged (MO) males. This implies that some of the MO males were more active and aggressive in the fights. During the 1.5 year period, 5/6 of the YA and 5/17 of the MO males made intergroup shifts. Although YA males faced a high risk of receiving wounds at transfer, they usually rose in rank. On the other hand, the MO males transferred more smoothly but dropped in rank. The peripheral SA males, which rarely emigrated in the population, were an active component in determining the wounding rate, and the rate and direction of male migration. Three SA immigrants died of severe attacks made by resident males in 1988 and 1991. Adult sex ratios and their variations were considerably reduced with male nonrandom shifts and better conservation of the population.
Resumo:
Bioaccumulation of PCDD/F in the foodweb was investigated in the Ya-Er Lake area, which was heavily polluted by PCDD/F. The high concentrations of PCDD/F in sediment can be transferred and bioaccumulated by aquatic organisms and humans through various pathways. Benthonic invertebrate animals and aquatic plants with a lot of fibers in the root can accumulate PCDD/F from sediment and water. Snail (Bellamya aeruginosa), shrimp (Macrobranchium sp.) and freshwater mussel (Acuticosta chinensis (Lea)) took up PCDD/F from the water and maintained the emission patterns, whereas fish tended to selectively accumulate 2,3,7,8-substituted isomers. The tissues of fish-eating bird and duck (Anas platyrhynchos) were very highly contaminated by PCDD/F due to ingestion of fish and other aquatic organisms from sediment. The residual concentration in breast milk depended on the original concentration of PCDD/F in the food. A resident in Ya-Er Lake area showed a daily intake of PCDD/ F of about 9.14 pg TEQ/kg body weight/day. This is higher than the tolerable daily intake (TDI) for PCDD/F (1 pg TEQ/kg body weight/day), which was recommended by the World Health Organization (WHO). (C) 2001 Elsevier Science Ltd. All rights reserved.
Resumo:
Three causes involved in the instability of the ISFET are proposed in this study. First, it is ascertained that hydroxyl group resident at the surface of the Si3N4 film or in the electrolyte solution is most active and subject to gain or loss of electrons. This is one of the main causes for ISFET structural instability. Secondly, the stability of the pH-sensitive FET varies with deposition conditions in the fabrication process of the ISFET. This proves to be another cause of ISFET instability. Thirdly, the pH of the measured solution varies with the measuring process and time, contributing to the instability, but is not a cause of the instability of the pH-ISFET itself. We utilized the technique of readjusting and controlling the ratio of hydroxyl groups to amine groups to enhance the stability of the ISFET. Our techniques to improve stability characteristics proved to be effective in practice.
Resumo:
以典型黄土丘陵沟壑区——延安市赵庄村为例,选取土地利用动态度、土地利用趋势状态指数、土地利用景观指数等指标,对村庄尺度上的土地利用变化进行了定量分析。结果表明,6 a来,研究区土地利用发生了较大的变化,主要以耕地的减少和未利用土地的增加等变化为主;未利用土地、居住及建设用地、林地、灌草地以不同程度增加,其动态度大小依次为43.92%,15.35%,0.33%,0.17%;而耕地、果园、水域则以不同程度减小,动态度大小依次为7.45%,3.79%,0.20%;耕地、果园、水域呈"落势"状态,而未利用土地、居住及建设用地、林地、灌草地呈"涨势",朝着规模增大的趋势发展;斑块数与斑块密度增加,优势度指数与偏离度指数减小,多样性指数、均匀度指数和破碎度指数都有不同程度的增大。
Resumo:
Calreticulin (CRT), as an endoplasmic reticulum luminal resident protein, plays important roles in Ca2+ homeostasis and molecular chaperoning. CRT on the surface of the cell can modulate cell adhesion, phagocytosis and integrin-dependent Ca2+ signaling. The full length cDNA of calreticulin (FcCRT) was cloned from Chinese shrimp Fenneropenaeus chinensis. It consists of 1672 by with an open reading frame of 1221 bp, encoding 406 amino acids. This is the first reported cDNA sequence of calreticulin in Crustacea. The deduced amino acid sequence of FcCRT showed high identity with those of Bombyx mori (88%), Drosophila melanogaster (83%), Mus musculus (82%) and Homo sapiens (82%). Highest expression of FcCRT was detected in ovary by Northern blot and in situ hybridization. Different mRNA levels of FcCRT were detected at various molting stages. Expression of FcCRT was induced significantly after 3 h of heat shock treatment, reached the maximum at 4 h and dropped after that. Differential expression profiles of FcCRT were observed in hepatopancreas and haemocytes when shrimp were challenged by white spot syndrome virus (WSSV). From the above results, we inferred that FcCRT might play important roles in Ca2+ homeostasis, chaperoning and immune function in shrimp. (c) 2007 Elsevier Inc. All rights reserved.
Resumo:
Population data which collected and saved according to administrative region is a kind of statistical data. As a traditional method of spatial data expression, average distribution in every administrative region brings population data on a low spatial and temporal precision. Now, an accurate population data with high spatial resolution is becoming more and more important in regional planning, environment protection, policy making and rural-urban development. Spatial distribution of population data is becoming more important in GIS study area. In this article, the author reviewed the progress of research on spatial distribution of population. Under the support of GIS, correlative geographical theories and Grid data model, Remote Sensing data, terrain data, traffic data, river data, resident data, and social economic statistic were applied to calculate the spatial distribution of population in Fujian province, which includes following parts: (1) Simulating of boundary at township level. Based on access cost index, land use data, traffic data, river data, DEM, and correlative social economic statistic data, the access cost surface in study area was constructed. Supported by the lowest cost path query and weighted Voronoi diagram, DVT model (Demarcation of Villages and Towns) was established to simulate the boundary at township level in Fujian province. (2) Modeling of population spatial distribution. Based on the knowledge in geography, seven impact factors, such as land use, altitude, slope, residential area, railway, road, and river were chosen as the parameters in this study. Under the support of GIS, the relations of population distribution to these impact factors were analyzed quantificationally, and the coefficients of population density on pixel scale were calculated. Last, the model of population spatial distribution at township level was established through multiplicative fusion of population density coefficients and simulated boundary of towns. (3) Error test and analysis of population spatial distribution base on modeling. The author not only analyzed the numerical character of modeling error, but also its spatial distribution. The reasons of error were discussed.