622 resultados para 13200-091
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Based on the data collected from New Ferry Wharf, Sassoon Dock and exploratory survey of MFV Saraswati on the Northwest coast of India, the growth, mortality, population and stock parameters of Saurida tumbil is reported in the present communication. The Von Bertalanffy growth function (GF) parameters for growth on length were found to be L∞=49.8 cm, K=0.96/year, t0 = -.141 year. The length at recruitment (lr) is 80 mm. (tr=.167 year) while the length at first capture (lc) for the commercial trawl fishery is 100 mm (tc=0.25 year). The annual fishing mortality coefficient (F) for 1983-85 was 0.43, the natural mortality coefficient (M) was 1.33 and the exploitation ratio (E) was 0.25. The yield per recruit (Y/R) attained the maximum of 54.99 g at F=1.091 for E=0.45 for the present tc at 0.25 year. The annual total stock (P) and standing stock (P) in the exploitation portion at the inshore grounds to a depth of about 50 m were estimated to be 12,811 tons and 6,034 tons respectively. The average annual yield of 2,635 tons at the present F=0.439 (E=0.247) was less than the maximum sustainable yield (MSY) for 3,331 tons attainable from the inshore grounds at E=0.45.
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A Gram-positive bacterium, designated strain CW 7(T), was isolated from forest soil in Anhui Province, south-east China. Cells were strictly aerobic, motile with peritrichous flagella and rod-shaped. The strain grew optimally at 30-37 degrees C and pH 7.0-8.0. The major fatty acids of strain CW 7(T) were anteiso-C-15:0, iso-C-15:0 and anteiso-C-17:0. The predominant menaquinone was MK-7. The cell-wall peptidoglycan contained meso-diaminopimelic acid. The G + C content of the genomic DNA was 42.3 mol%. Phylogenetic analysis indicated that strain CW 7(T) belonged to a monophyletic cluster within the genus Bacillus and showed 16S rRNA gene sequence similarities of less than 96.5% to recognized species of the genus Bacillus. The results of the polyphasic taxonomic study, including phenotypic, chemotaxonomic and phylogenetic analyses, showed that strain CW 7(T) represents a novel species of the genus Bacillus, for which the name Bacillus pallidus sp. nov. is proposed. The type strain is CW 7(T) (=KCTC 13200(T)=CCTCC AB 207188(T)=LMG 24451(T)).
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The BRUNOL/CELF family of RNA-binding proteins plays important roles in post-transcriptional regulation and has been implicated in several developmental processes. In this study, we describe the cloning and expression patterns of five Brunol genes in Xenopus laevis. Among them, only Brunol2 is maternally expressed and the zygotic expression of the other four Brunol genes starts at different developmental stages. During Xenopus development, Brunol1, 4-5 are exclusively expressed in the nervous system including domains in the brain, spinal cord, optic and otic vesicles. Brunol2 and 3 are expressed in both the somatic mesoderm and the nervous system. Brunol2 is also extensively expressed in the lens. In transfected Hela cells, BRUNOL1, 2 and 3 proteins are localized in both the cytoplasm and the nucleus, while BRUNOL4 and 5 are only present in the cytoplasm, indicating their different functions.
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真核生物的线粒体一般具有一定的典型的结构和功能。然而,在单细胞的寄生原生动物中却不断发现从数量、结构到功能均与典型线粒体明显不同的线粒体,表现出线粒体的巨大可塑性和丰富的多样性。该文对寄生原生动物中这些多样的线粒体进行了概述,并对形成这种多样性的根本原因,即这些生物对寄生生活微氧或无氧环境线粒体所发生的种种适应性进化进行了分析探讨。
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Using a combined computational program. we identified 50 potential microRNAs (miRNAs) in Giardia lamblia. one of the most primitive unicellular eukaryotes. These miRNAs are unique to G. lamblia and no homologues have been found in other organisms; miRNAs.
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A birnavirus strain, Paralichthys olivaceus birnavirus (POBV), was isolated and characterized from cultured flounder in China, and its complete genomic sequence was subsequently determined. The virus could induce cytopathic effects (CPE) in four of seven fish cell lines and was resistant to chloroform, 5-iodo-2'-deoxyuridine, acid and alkaline pH, and heat treatment. Purified virus particles had a typical icosahedral shape, with a diameter of approximately 55-60 nm. The genomic segments A and B of POBV were 3,091 and 2,780 bp in length and shared many of the features of the members of the family Birnaviridae. Segment A contained two partially overlapping ORFs encoding a polyprotein, pVP2-VP4-VP3, and a nonstructural protein, VP5, while segment B had only one ORF encoding for the VP1, a viral RNA-dependent RNA polymerase (RdRp). This is the first report about a birnavirus strain from a new non-salmonid host in China and its complete genome sequence.
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A Sb-mediated growth technique is developed to deposit Ge quantum dots (QDs) of small size, high density, and foe of dislocations. These QDs were grown at low growth temperature by molecular beam epitaxy. The photoluminescence and absorption properties of these Ge QDs suggest an indirect-to-direct conversion, which is in good agreement with a theoretical calculation. (C) 1998 American Institute of Physics. [S0003-6951(98)00420-3].
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澜沧江姬鼠(Apodemus ilex)为小型啮齿类动物,长期以来常被认为是中华姬鼠(A. draco)或长尾姬鼠(A. orestes)的同物异名,但近年基于线粒体Cyt b 的研究证明,该类群与中华姬鼠的遗传距离达到了种间水平,并被认为是一个独立种。本文提取、扩增并测定了来自云南14个地区42个产地156个澜沧江姬鼠的Cyt b 全序列,并将GenBank中的3条澜沧江姬鼠的Cyt b 全序列纳入分析,选取福建武夷山与四川峨眉山的2个中华姬鼠样品的Cyt b 全序列,以及台湾姬鼠、大耳姬鼠、高山姬鼠Cyt b 全序列作为外群,利用贝叶斯法和最大似然法构建系统发育树,并使用Network分析,分子变异分析(AMOVA)分析、错配分析(Mismatch analysis)与Fu`Fs检验等方法,探讨了这些地区澜沧江姬鼠的种群遗传结构,种群动态及生物地理格局。结果表明:云南地区过去被鉴定为中华姬鼠的样品均属于澜沧江姬鼠,澜沧江姬鼠与中华姬鼠间的遗传距离(K2P-ds+v)达到0.091,显著超过姬鼠属内种间差距(0.080),支持澜沧江姬鼠独立种的地位;该种不同地理种群可大致以澜沧江为界分为两大支系,且每个支系又各分为两个亚支系;进一步的AMOVA分析表明遗传变异主要来源于两大支系之间,而错配分析与Fu`Fs检验表明澜沧江姬鼠各地理种群及其两个支系都经历过多次扩张事件,这可能是和冰期与间冰期的轮回交替有关;分子系统树和中介网络图表明地理环境的隔离对于澜沧江姬鼠种群分化存在明显影响,其中澜沧江的阻隔作用最为显著。基于松散分子钟(Relax molecular clock)分析,中华姬鼠和澜沧江姬鼠的分歧时间大约在2.98 Ma(95%HPD: 4.32-1.88),而澜沧江姬鼠则在1.13 Ma(95%HPD: 1.95-0.65)分成两个支系。按照平均分歧时间来看,澜沧江姬鼠两个支系的的分歧事件发生在鄱阳冰期(1.2-0.9 Ma),两个支系内部进一步分化为两支的时间非常接近,分别为:Clade 1中为0.67 Ma (95%HPD: 1.17-0.34)和Clade 2 中为0.64 Ma (95%HPD: 1.17-0.36),这种隔离种群各自产生分化的时间却非常接近,这提示其分化事件可能是受到古气候如冰期或间冰期的影响所产生。
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论文采用国家铁路省际间煤炭资源的交流数据、动力煤价格数据,以全国最大的煤炭输出省--山西为例,运用回归分析等统计方法,分析了资源区域流动的驱动因子。基于场论,提出了测度资源区域流动潜力的方法。主要结论有:①资源区域流动的主要驱动因子有距离、价格差;②在显著性水平α=0.05下,区域煤炭价格差与晋煤净输流量呈正向变化,但线性无关,源汇间距离与晋煤净输流量呈线性负相关;③2005年晋煤净输流量与源汇间距离符合F=e9.091-0.003D的Growth回归模型;④资源势差涵盖了影响煤炭流动的流量和距离等2个主
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[Al(C15H9O3)(3)](2) . 2CHCl(3) . 8H(2)O was synthesized, and its crystal structure was determined. It belongs to trigonal system, R3, a=b=1. 655 8(3) nm, c=3. 646 5(20) nm, alpha = beta = 90 degrees, gamma = 120 degrees, V = 8. 656 08(0. 005 86) nm(3). D-c = 1.45 g/cm(3), mu(Mo K alpha) = 3. 20 cm(-1), F (000) = 3 924. The crystal structure was solved by Patterson and Fourier techniques, and refined by a block-diagonal least-squares method. A total of 3 737 independent intensity data were collected, of which 1 033 with I greater than or equal to 3 sigma(I-0) were observed, R = 0. 091 8, Rw=0. 091 8. Al3+ ion was 6-coordinated, bound to six oxygen atoms from three 3-hydroxyflavones to form a distortional coordination octahedron.
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长牡蛎是重要的经济养殖贝类,良种化、抗逆性状及快速生长个体的培育是长牡蛎养殖业得以持续发展的基础。目前飞速发展的分子标记辅助育种技术为优良品种的快速培育提供了理论基础和实践经验。本研究以长牡蛎为主要研究材料,探讨了长牡蛎SNP标记的筛选和多态性评价。 本研究利用已有长牡蛎EST库中的序列进行单核苷酸多态(SNP)标记开发。通过对长牡蛎(Crassostrea gigas)已有的EST序列数据库检索,经过序列聚类和拼接得到EST簇4548个,含有不少于4条EST序列的簇共1079个,经过进一步设置筛选条件,整理出可供利用的EST簇313个,得到候选SNP位点共计1140个。目前根据候选SNP位点共设计引物82组,通过片段长度差异等位基因特异性PCR(fragment length discrepant allele specific PCR,FLDAS-PCR)的分型方法,在一野生群体中进行检测和验证,结果共有17个SNP候选位点显示多态性,期望杂合度分布区间为0.088至0.506,观测杂合度分布区间为0.091至0.667;通过哈代-温伯格(HW) 平衡、连锁不平衡检验,结果显示除3个SNP位点的差异显著(P值<0.05),不符合HW平衡之外,其他14个位点没有明显的连锁不平衡。对含有17个SNP的EST的共同序列进行BlastX分析,推测其功能并确定开放阅读框,从而预测17个SNP的性质。 本研究表明对于目前基因组学研究尚处在初级阶段的海洋生物物种,通过基于EST数据库的SNP开发是一条重要途径,可以有效弥补海洋生物基因组学滞后影响SNP标记开发的现状。
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对海北定位站地区分布的金露梅灌丛草甸、矮嵩草草甸和沼泽化藏嵩草草甸3种高寒植被类型群落及土壤环境因子的观测结果表明:3种植被类型地上年净生产量依次为矮嵩草草甸(339.594 g/m2)>沼泽化藏嵩草草甸(339.358 g/m2)>金露梅灌丛草甸(278.299 g/m2);光能利用率为矮嵩草草甸(0.099%)>沼泽化藏嵩草草甸(0.091%)>金露梅灌丛草甸(0.075%);植被群落的种类组成为矮嵩草草甸(54种)>金露梅灌丛草甸(47种)>沼泽化藏嵩草草甸(24种).观察矮嵩草草甸和金露梅灌丛草甸0~20 cm土壤温湿度表明,矮嵩草草甸土壤温度>金露梅灌丛草甸,土壤湿度则相反,其中矮嵩草草甸土壤温度较高,土壤湿度较低,金露梅灌丛草甸则是高土壤湿度和低土壤温度,而沼泽化藏嵩草草甸土壤湿度达饱和甚至超饱和状态,土壤温度显得更低.
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Suganami, H., C.A.W.Manning and the Study of International Relations, Review of International Studies (2001), 27 : 091-107 RAE2008