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Effect of tail loss on energy stores and locomotor performance in the blue-tailed skink,Eumeces elegans

LIN Zhihua,FAN Xiaoli,LU Hongliang,LUO Laigao,JI Xiang School of Chemistry,Life Sciences,Lishui University,Lishui,China School of Life,Environmental Sciences,Hangzhou Normal University,Hangzhou,China College of Life Sciences,Nanjing Normal University,Nanjing,China,

生态学报 , 2010,
Abstract: Tail autotomy is a major defensive strategy to escape from predation in many species of lizards. Although tail loss provides an immediate survival benefit,it may entail substantial costs. A total of 117 blue-tailed skinks (Eumeces elegans) were collected from a population in Lishui to evaluate energetic and locomotor costs of tail loss. Of the 117 skinks,81 (c. 69%) had autotomized some portion of the tail at least once. The blue-tailed skink in this population showed a high tail-break frequency,and therefo...
The effects of forest patch sizes on bird species diversity and individual density

Wenhong Deng,Wei Gao Ministry of Education Key Laboratory for Biodiversity,Ecological Engineering,College of Life Sciences,Beijing Normal University,Beijing,China School of Life Sciences,Northeast Normal University,Changchun,China,

生物多样性 , 2005,
Abstract: More and more continuous forests become fragmented because of natural events and human dis- turbance. This change will affect the distribution patterns and behavior characteristics of animals living in forests. Using point count methods, we investigated bird species diversity and individual density in 18 forest fragments (area: 4.3 to 76.9 hm2) in Zuojia Nature Reserve, Jilin Province during the spring and summer of 2000 and 2001. The main objectives of this research were to assess whether there exist area effects affecting bird species diversity and individual density in a fragmented forest. There was no significant difference of indices of bird diversity between the two years. However, the individual density of birds differed signifi- cantly in the two years. Our results also indicated that there were significant differences in bird diversity among forest patches, with the number of bird species ranging from 12 to 43. Although several large forest patches contained relatively fewer bird species, the bird species tended to increase with size of forest patch. Different bird species respond to forest patch size differently. White-checked starling (Sturnus cineraceus), brown shrike (Lanius cristatus) and black-faced bunting (Embriza spodocephala) preferred small patches, whereas forest wagtail (Dendronanthus indicus), olive-backed pipit (Anthus hodgsoni) and grey-backed thrush (Turdus hortulorum) rarely occurred in small patches. Basically, the relationship between area size and species number was in accordance with the classical theory of island biogeography, but the Z and C values were very different from those predicted. We found a threshold phenomenon in the relationship between patch area and number of bird species such that the number of bird species did not change significantly when the patch size was greater than 30 hm2. Thus, it is not suitable to use the classical theory of island biogeog- raphy directly to predict species diversity or for designing nature reserves for a fragmented forest landscapes.
Complexity of forest communities:a case study of three different forest types in Heishiding Nature Reserve, Guangdong

QIN Lin,YU Shi-Xiao School of Life Sciences,Sun Yat-sen University,Guangzhou,

生物多样性 , 2004,
Abstract: 本文将森林群落复杂性定义为消除群落中任意一个树木个体的种名及层次不确定性所需的平均信息量,提出用联合熵H(X,Y)测度群落复杂性.H(X,Y)=H(X)+H(Y|X),其中H(X)=-∑Si=1(ni)/(N)log2((ni)/(N)),H(Y|X)=-∑Si=1(ni)/(N)∑4j=1(nij)/(ni)log2((nij)/(ni)),分别为树种组成复杂性和树种结构复杂性.式中S为森林群落树种数,N为森林群落的树木总株数,ni(i=1,2,...,S)为第i个树种的株数,nij(j=1,2,3,4)为第i个树种在第j层次的株数.用联合熵分析了广东省封开县黑石顶自然保护区针叶林、针阔混交林和常绿阔叶林等3种典型森林类型的复杂性.结果表明,群落复杂性的顺序为常绿阔叶林>针阔混交林>针叶林.同时,各森林类型的群落复杂性H(X,Y)与取样尺度之间具有较好的分形关系.
Minimum sampling area and species diversity of coastal Vatica hainanensis forest in Shimei Bay, Hainan Island

YAN Wen-Hong,HU Yu-Jia School of Life Sciences,Sun Yat-sen University,Guangzhou,

生物多样性 , 2004,
Abstract: Coastal Vatica hainanensis forest in Hainan is a special type of tropical rainforest. To analyze this community, we used methods of sampling area analysis, including both quantitative mathematical modeling and qualitative comparison. 8 different mathematical models (species-area curves) were used to calculate the minimum sampling area and relevant coefficients. Importance values were derived to confirm the modeling consequences. Species diversity was also analyzed by various kinds of diversity indices. Results showed that the minimum sampling area of coastal Vatica hainanensis forest in Shimei Bay was 800 m2. This value of minimum sampling area was the lowest in global tropical rainforest types. Coastal Vatica hainanensis forest in Shimei Bay was a strongly mono-dominant forest with low species diversity. Thirdly , the pattern of tree layers in Shimei Bay, measured by the Gleason index, differed greatly from that of mountain rainforest on Hainan Island. The study revealed that Shimei Bay, Hainan Island hosts a natural rainforest climax community which has low species diversity and salient mono-dominant community characteristics.
Factors influencing the population status of wild Chinese alligators (Alligator sinensis)

DING You-Zhong,WANG Xiao-Ming School of Life Sciences,East China Normal University,Shanghai,

生物多样性 , 2004,
Abstract: During April - August 1998, 200 questionnaires were distributed and collected in each of 200 towns and villages in the National Chinese Alligator Nature Reserve in Anhui Province. Based on the re- sults of the questionnaires, quantitative nocturnal spotlight surveys were carried out from July to October of 1999, 2000, 2001, 2002 and 2003 in areas most likely to have wild alligator populations. The survey area included 36 sites in five counties or municipalities (Xuancheng, Jingxian, Guangde, Langxi, Nan- ling) in Anhui Province, seven sites in Changxing County and Anji County of Zhejiang Province, and two sites (Fuxijian and Dahanjie) near Yixing City in Jiangsu Province. Based on these surveys we estimate that the current size of the wild Chinese alligator population in Anhui and Zhejiang Provinces is 120 individuals. The population is fragmented into 23 isolated small lo- cal populations with 1 - 10 individuals each. No alligators were found in Jiangsu Province. Analysis of our data revealed that the wild Chinese alligator population and its distribution have declined sharply since the 1950s. The current population size of wild Chinese alligators has declined an estimated 76.5% from its levels in the 1980s. However, the population appears to have been stable from 1998 to 2003 with an estimated 120 individuals. The factors most responsible for the population decline have varied over the last fifty years but overall have been habitat fragmentation and degradation, hunting, natural disasters (floods and drought), low productivity and pollution. From the 1950s to 1990s, habitat loss and the killing of alligators were the most significant factors. Presently, killing of alligators is less of an issue but the loss of habitat has been virtually complete. Therefore, the highest priority for conservation of Chinese alligators must be habitat restoration as the first step towards reintroducing alligators by releasing captive-bred individuals. In addi- tion, the potential consequences of environmental pollution and reduced genetic diversity of wild Chinese alligator population must also be addressed.
Transfer of small chromosome fragments of Agropyron elongatum to wheat chromosome via asymmetric somatic hybridization
WANG Jing,XIANG Fengning,XIA Guangmin,CHEN Huimin,
,XIANG Fengning,XIA Guangmin & CHEN Huimin School of Life Sciences,Shandong University,Jinan,China

中国科学C辑(英文版) , 2004,
Abstract: The chromosome constitution of hybrids and chromatin patterns of Agropyron elongatum (Host)Neviski in F5 somatic hybrid lines II -1-3 and I-1-9 between Triticum aestivum L. and A. elongatum were analyzed. Based on the statistic data of pollen mother cells, F5 I-1-9 and II-1-3 had 20-21 bivalents with a frequency of 84.66% and 85.28%, of which, 89.83% and 89.57% were ring bivalents. The result indicated that both hybrid lines were basically stable in the chromosome constitution and behavior. RAPD analysis showed that the two hybrids contained biparental and integrated DNA. GISH (Genome in situ hybridization) revealed that in the form of small chromosome segments, A. elongatum chromatin was scattered on 4-6 wheat chromosomes near by the region of centromere and telomere in the two hybrid lines. SSR analysis indicated that A. elongatum DNA segments were distributed on the 2A, 5B, 6B and 2D wheat chromosomes in the hybrids, which was in accordance with the GISH results that small-segments intercalated poly-site.
Effects of cadmium stress on photosynthesis and antioxidant systems in Mirabilis jalapa under different light intensities

KE Shisheng,ZHANG Chongbang,WANG Jiang School of Life Sciences,Taizhou University,Linhai,

环境科学学报 , 2009,
Abstract: The effects of excessive cadmium (30 mg·kg-1 in soils) on plant growth, photosynthesis, lipid peroxidation, the activities of antioxidant enzymes, the contents of photosynthetic pigments, Cd, Mg, Fe, K, ascorbic acid (AsA) and glutathione (GSH) in Mirabilis jalapa plants were investigated and compared under high light (HL, fully exposed to ambient sunlight), intermediate light (ML, about 50% of full ambient sunlight) and low light (LL, about 10% of full ambient sunlight) conditions. The net photosynthetic rate (Pn) in the presence of excessive Cd in soils decreased more under HL treatment than under ML and LL treatments. Excessive Cd significantly reduced the maximal photochemical efficiency (Fv/Fm) under HL and LL treatments, but did not affect Fv/Fm under ML treatment. Excessive Cd remarkably increased the dark respiration rate (Rd), especially under ML treatment. The growth of plants was significantly inhibited in the presence of excessive Cd, especially under HL treatment. Excessive Cd greatly increased the Cd content, and reduced the contents of chlorophyll, carotinoid, Mg, Fe and K in the leaves, particularly under HL treatment. Under HL treatment, excessive Cd greatly increased the activities of superoxide dismutase (SOD) and guaiacol peroxidase (POD), the contents of hydrogen peroxide (H2O2), superoxide (O-·2) and malondialdehyde (MDA), and electrolyte leakage, whereas it decreased the activities of catalase (CAT) and ascorbate peroxidase (APX), and the contents of GSH and AsA. The results indicate that excessive Cd enhanced oxidative stress and growth inhibition to Mirabilis jalapa plants, especially under HL treatment.
Protein interaction and change of protein conformation and dynamics

Shi YunYu & Wu JiHui Hefei National Laboratory for Physical Sciences at Microscale,School of Life Science,University of Science,Technology of China,Hefei,China,

科学通报 , 2009,
Abstract: Understanding protein interaction from the view of structural biology is important for understanding protein function in the cell. Nuclear magnetic resonance (NMR) is an important method in structural biology. To investigate molecular interactions by NMR spectroscopy is generally at a close physio-logical condition. This method particularly suites for studying transient dynamical complexes. NMR belongs to few techniques which can provide information for the unstructured or partial structured proteins. NMR a...
Role of frequency band integration in sharpening frequency tunings of the inferior colliculus neurons in the big brown bat, Eptesicus fuscus
WU Feijian,CHEN Qicai,JEN Philip H S,SHEN Junxian School of Life Sciences,Central China Normal University,Wuhan,China Division of Biological Sciences,University of Missouri-Columbia,MO,USA Laboratory of Vsual Information Processing,

科学通报(英文版) , 2004,
Abstract: By means of a particular two-tone stimulation paradigm in combination of using a pair of electrodes for simultaneously recoring from two inferior colliculus (IC) neurons,the current in vivo study is undertaken to explore the role of frequency band integration (FBI) in sharpening of frequency tuning in the big brown bat, Eptesicus fuscus. Three major results are found: (1) The paired neurons cor- related to FBI are located not only within the same frequency filter bandwidth (FFB), but also across different FFBs. The relations of their frequency tuning curves (FTCs) are mainly of two types: the flank-overlapped and overlaid patterns. (2) Although the sharpness of FTCs between paired neurons is mutual, the sharpening efficiency of neurons located within the same FFB is higher than that of neurons across FFBs, and the FTCs of neurons with the best frequencies (BF) of 20 --30 kHz are most strongly sharpened. (3) The strength of FBI is weak near the BF but gradually increased with fre- quencies away from the BF of sound stimuli. This suggests that the dynamical FBI of the IC neurons located within and across the FFBs might be involved in the formation of func- tional FFB structures.
The effects of proteasome inhibitor lactacystin on mouse oocyte meiosis and first cleavage
TAN Xin,PENG An WANG Yongchao TANG Zuoqing,
,PENG An,WANG Yongchao & TANG Zuoqing . School of Life Sciences and Technology,Beijing Institute of Technology,Beijing,China,. College of Life Sciences,Beijing Normal University,Beijing,China,. College of Basic Medicine,Capital University of Medical Sciences,Beijing,China

中国科学C辑(英文版) , 2005,
Abstract: In order to study the effects of ubiquitin-proteasome pathway (UPP) on mouse oocyte meiosis and cleavage, oocytes undergoing maturation and parthenogenetic activation and 1-cell embryos were treated with lactacystin, a specific inhibitor of proteasome. The results indicated that the rate of GVBD was not influenced by the treatment, but polar body extrusion, parthenogenesis and first cleavage were inhibited. Immunofluorescent staining using anti beta-tubulin antibody indicated that the continuous treatment of lactacystin from GV stage disorganized microtubules and spindle assembly. When metaphase stage oocytes were treated with the drug, the already formed spindle structure was not affected, but the oocytes were arrested at metaphases. The 1-cell embryos were arrested at interphase or metaphase of first mitosis when they were incubated in the drug. Proteasome regulatory subunit PA700 was located in the spindle region, as indicated by immunofluorescence. These results suggest that UPP has effects on the process of oocyte meiosis and early cleavage in many aspects, including normal organization of spindle at prophase and segregation of chromosomes at anaphase for normal meiosis.
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