26 resultados para Golden Parachutes


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The structures, properties and electron transfer reactivity of the ClO/ClO- coupling system are studied in this paper at ab initio (UHF and UMP2) levels and the Density Functional Theory (DFT: UB3LYP, UB3P86, UB3PW91) levels employing 6311 + G(3df) basis set and on the basis of the Golden-rule of the time-dependent perturbation theory. Investigations indicate that the results obtained using the UB3LYP method employing 6-311 + G(3df) basis set is in excellent agreement with the experiment. For this coupling system, six stable coupling modes have been found which correspond to six different encounter complexes and denote six different electron transfer mechanism: four O-O directly linked structures (one collinear: D-h, one anti-parallel: C-s, two twist: C-2) and two Cl-O linked structures (cis- and anti- C-s structures). The activation energies, the stabilization energies and the electronic coupling matrix elements have also been calculated for the electron transfer reactions via these six different mechanism at the UB3LYP/6-311 + G(3df) level, and then the electron transfer rates are determined at the same level. The most favorable coupling mode to the electron transfer is the anti-parallel mechanism. The averaged electron transfer rate is about 5.58 X 10(11) M-1 s(-1). It is also implied that the B3LYP method can give more reasonable results for the electron transfer reactivity of this system. (C) 2003 Elsevier B.V. All rights reserved.

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The Sichuan golden monkey (Rhinopithecus roxellana) is a famous and beautiful endangered primate. Owing to the dearth of samples and technical limitations, previous studies could not adequately assess the levels of genetic polymorphisms in the species. To

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2004年10月,中国科学院昆明动物研究所首次发现金苹果螺(Pomacea canaliculata)入侵重要的水源保护区嵩明白邑黑龙潭.金苹果螺起源于中南美洲,在亚洲,它通过有意或无意的传播而逐渐扩散到菲律宾、越南、泰国、老挝、柬埔寨、马来西亚、印尼、巴布几内亚、韩国、日本和中国的南部.金苹果螺已成为水稻产区的最大害虫,给农业生产带来巨大的损失.为防止金苹果螺在云南扩散,目前已经实施了严格的预防、控制措施,同时开展了公众保护教育宣传活动.

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The masticatory apparatus for two endemic species of golden monkey in China, Rhinopithecus bieti and Rhinopithecus roxellana, were compared with those of macaques, Macaca and leaf monkeys, Presbytis. Multivariate analyses demonstrated that the two golden monkey species are distinct. Interspecies allometric analyses revealed that golden monkeys differ in their masticatory apparatus from both macaques and leaf monkeys. The prominent symphysial fusion, corpus, and sagittal condylar dimension of R. roxellana may produce efficient biting force on the incisal and posterior canine teeth, with the heavy reaction force barn on the temporomandibular joint. However, the well-developed bizygamatic width and mandibular height in R. bieti suggest that posterior canine function is similarly prominent in R. roxellana, while incisal function is not. (C) 1995 Wiley-Liss, Inc.

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Although infanticide has been witnessed in many species of Colobinae, and a case was observed in a captive group of golden snub-nosed monkeys (Rhinopithecus roxellana), observed cases of infanticide in wild snubnosed monkeys (Rhinopithecus spp.) have not

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The morphology of two species of bucephalids (Bucephalidae; Digenea; Trematoda), which since 1999 has caused a fish disease at the Uji River, Kyoto Prefecture, Japan, is described. Parabucephalopsis parasiluri Wang, 1985 was first recorded in the Uji River in 2000, and Prosorhynchoides ozakii (Nagaty, 1937) in 2005. The definitive host of both species is the Lake Biwa catfish (Silurus biwaensis), and the second intermediate hosts include many fish species from several families. P. parasiluri is an introduced parasite that invaded with its first intermediate host, golden mussels (Limnoperna fortunei), from the Asian continent. P ozakii may also be an introduced species, although its first intermediate host has not been identified. (C) 2007 Elsevier Ireland Ltd. All rights reserved.

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本文包括两方面有关灵长类的研究工作。一是构建了一个非人灵长类(滇金丝猴)的人工染色体文库(BAC文库),为进一步研究灵长类的基因组进化奠定了一定的基础,二是对一个认知相关基因neuotrypsin在灵长类中的分子进化进行了详尽的研究,以期从分子进化角度认识该基因在灵长类高级认知功能发展中所起的作用。滇金丝猴(Rhinopithecusbieti),一个处于严重濒危状态的旧大陆猴,中国特产灵长类之一。在系统发育上它占据着旧大陆猴与小猿的中间地位,是研究灵长类进化的一个重要物种。,在本研究中,我们构建了一个滇金丝猴的细菌人工染色体文库(BAC文库)。该文库含有136320个BAC克隆,平均插入片段大小为148kb,小片段(50-100kb)所占的比例为2.74%,非重组克隆仅占2.67%。假定金丝猴与亲缘关系较近的灵长类有着相似的基因组大小,该文库至少有6倍的基因组覆盖率。对随机选取的BAC克隆进行末端测序,我们获得了201个序列标签(STS)。通过荧光原位杂交(FISH)技术,139个经末端测序的BAC克隆被精确定位到滇金丝猴的染色体上。荧光杂交实验还表明了人和金丝猴染色体产存在着高度的同线保守性。在人类基因组数据库中的Blast搜寻的结果显示染色体上的克隆数目与染色体大小呈很好的相关性,表明该文库克隆比较均匀地覆盖了滇金丝猴的基因组。该金丝猴文库及所定位的克隆将会成为非人灵长类的比较基因组研究和大规模基因组测序的一个宝贵的资源。Neurotrypsin是与个主要在脑中表达的,同神经发育和认知功能相关的胞外丝氨酸蛋白酶。它在人体中发生的突变与常染色体上隐性的非综合性精神发育迟缓(MR)紧密相关。我们通过对n个非人灵长类,包括大猿、小猿、旧大陆猴和新大陆猴neurotrypsin的编码区的测序,研究了neurotrypsin在灵长类中的分子进化。结果显示出,在灵长类进化过程中,neurotrypsin保持着由纯化性选择(负沟选择)所致的强烈的功能限制,这暗示着neurotrypsin在灵长类的认知发展中起着关键的功能性作用。进一步的分析表明,纯化性选择实际上只作用于neurotrypsin的介导其结合到其它细胞表面或胞外蛋白质的SRCR功能结构域上。另外,通过灵长类和其它哺乳动物目的比较,我们还发现,在鼠neuotrypsin中,一个人SRCR结构域(外显子2和3)的缺失是由于在鼠科动物中所发生的片段丢失事件所致。

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川金丝猴(RhinoPithecusroxellana)是我国著名的珍稀濒危保护动物,但是,现有的群体遗传学研究成果并不能满足科学合理的制定其遗传保护策略的要求。这主要是因为前人研究的遗传标记均是相对比较保守的功能基因,因此无法检测到足够的变异,进而也无法进行精细的分析。有鉴于此,我们选取了进化速率较快的线粒体控制区作为遗传标记,并对来自于三个主要栖息地的川金丝猴样本进行了群体遗传学研究。我们在线粒体控制区中观察到了大量的变异,这和前人的工作结果形成了强烈的反差。通过基于溯祖理论的最大似然法估算,我们得到现存川金丝猴群体的总的有效群体大小在700一2,300只以内,同时其最近共同祖先的年代在19,000-62,700年前左右。线粒体控制区的结果表明现存川金丝猴群体可能起源于眠山群体,我们称之为单起源假说,但是由于样本限制,多起源的可能性仍然存在。整个川金丝猴群体表现出显著的内部分化的信号,甚至氓山群体内部还存在一个序列分歧非常大的分枝,这可能是由其特殊的社群结构以及较弱的基因交流造成的,并且由于群体结构和分化信息的拮抗作用,我们并没有直接检测到瓶颈效应。通过和相关濒危与非濒危物种的比较,我们认为川金丝猴群体的遗传多样性水平并不低,提示其濒危的状态主要是由随机因素造成的而非遗传因素的结果。虽然我们在线粒体控制区中发现了大量的变异,但是前人在蛋白质电泳的研究中并未检出多态,同时,川金丝猴特殊的社群结构是否会影响其在核基因水平上的群体遗传结构也是十分有趣的问题,因此,为了从核基因组的角度进一步研究川金丝猴的遗传多样性,并实现对核基因和核外基因的比较,我们对样本的14个微卫星座位做了检测。我们发现这些微卫星座位均存在多态,所有地方群体的平均杂合度均大于0.5;地方群体间存在着显著的分化;地方群体间有效群体大小比率的估计值和群体大小比率的野外观测值非常接近。通过对比线粒体数据,我们认为川金丝猴的社群结构对其群体的遗传结构有着重要的影响,首先表现在核基因有更大的基因流水平,其次还表现在我们可以检测到眠山群体和秦岭群体在近期均经历了瓶颈效应,说明在核基因水平上群体结构信号的影响要弱于线粒体基因。但是,通过和其它物种比较,微卫星的数据却表明川金丝猴的遗传多样性水平并不高于其它的濒危动物,这和线粒体控制区的结果相反。这主要是当以微卫星为标记时,群体的历史动态对于当前群体的多态程度的影响力有限所致。微卫星的结果表明了保护川金丝猴群体的紧迫性。我们还通过细胞色素b基因证明了线粒体控制区中的巨大分歧不是由核假基因的造成的。巧合的是前人也在川金丝猴群体中对该基因进行过研究,但是结果却相反,即我们发现的变异水平远远高于他们的结果。为此,我们比较了两项工作的数据,我们推测在前人的工作中可能存在着潜在的测序错误。不过,如果没有出现污染的话,这两项工作的综合结果可以直接支持我们前面提到的单起源假说。此外,通过细胞色素b基因的分析,我们还估算出川金丝猴和滇金丝猴(R.bieti)的分歧时间大致在0.7-2.3百万年之间。镇金丝猴(R.biti)也是我国著名的濒危保护动物,它是川金丝猴的近缘种,其濒危等级甚至还要高于川金丝猴。迄今为止,关于滇金丝猴并基于DNA序列的的群体遗传学研究还没有见诸于报道。我们测定了来自于云南省维西县镇金丝猴群体样本的线粒体控制区全序列以及部分个体的细胞色素b全序列。在排除了核线粒体假基因存在的可能性之后,我们确认滇金丝猴维西群体内部也存在着两个序列分歧较大的分枝,但是,这可能是邻近群体迁移而来的产物。因此,如果考虑到群体结构和迁移的影响,我们认为维西群体的遗传多样性水平可能并不高。在以上的研究中,我们使用了大量的群体遗传学方法,但遗憾的是,目前还没有一套令人满意的侧重于群体遗传学分析的程序工具库。为了简化今后工作的复杂度和难度,我使用OCAAML语言编制了一套程序工具集(Pan'sToolKit,PTK)。OCAML是一门优秀的计算机语言,它既支持快速开发,又支持高速运行,是理想的算法实现语言。基于OCAML的PTK库集成了许多实用工具以及群体遗传学算法,尤其是溯祖理论的算法。PTK库不仅可以用于处理常规的实验数据,而且还可以用于辅助理论和算法的研究。

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针对异步电机效率优化问题,提出了一种混合搜索方法。该方法起始于模糊自适应搜索,然后切换至黄金分割法以获取确定收敛速度。这样的搜索步骤能够降低转矩波动,避免在最优点附近发生振荡。利用一个包含铁损和机械损耗的异步电机模型,对该方法进行了矢量控制下的性能验证。仿真结果验证了该方法的有效性。

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本文叙及一种新的轻型水下机器人(亦称无人遥控潜水器或ROV)——金鱼Ⅱ号。概要地描述了它的主要技术特点,系统总体结构,简要工作原理,及其适用范围。文中以在丰满电站进行实际作业为例,说明了该型水下机器人的应用前景。

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Located in the Paleozoic uplift along the southern margin of Tu-Ha basin in eastern Xinjiang, the newly discovered Hongshan Cu-Au deposit occurs in the superimposed Mesozoic volcanic basin upon the north section of later Paleozoic Dananhu-Tousuquan accretionary arc. Kalatage Cu-Au orebelt is controlled by NWW-trend faults, and includes Hongshan and Meiling Cu-Au deposits. The host rocks of Hongshan ore district are mainly rhyolitic-dacitic ignimbrites, whereas Cu-Au mineralization is closely related to quartz porphyry, rhyolitic porphyry and granitic porphyry. Mineralization styles are dominantly veinlet-disseminated and veinlet, occasionally stockwork. The mineral association is chalcopyrite, pyrite, bornite, chalcocite and sphalerite. The hydrothermal alteration consists of silicfication, sericitization, alunitization, pyrophylitization, illitization, hydromuscovitization, and chloritization. Hongshan Cu-Au deposit, on the edge of the desert, is one of the driest areas in eastrn Tianshan. Moreover, the highest temperature has been up to 60℃, and the average rainfall receives only 34.1mm/y. The light rainfall and rapid evaporation in the vicinity of this deposit have allowed the formation of a great variety of water-soluble sulfates. Oxidization zone of this deposit lies on the upper part of primary sulfide orebodies appearing with a depth of 50-60m, which is dominant in sulfate minerals. 1. Based on the field observation, the volcanic and sub-volcanic rock composition, hydrothermal alteration, ore structure and mineralization characteristics, this paper proposed that the Hongshan Cu-Au deposit belongs to a transitional type from high-sulfide epithermal to porphyry Cu-Au deposit, which corresponds with the typical HS-epithermal deposit such as Zijinshan Au-Cu deposit in Fujian Province, SE-China. 2. The Hongshan copper-gold deposit was controlled by the tectonic, stratum, magma activity and volcanic apparatus, whereas Au mineralization is closely related to quartz porphyry, rhyolitic porphyry and fine grained pyritization in hydrothermal activity, and Cu mineralization is closely related to quartz porphyry and hydrothermal explosive breccia. 3. Oxidation zone of Hongshan Cu-Au deposit lies on the upper part of primary sulfide orebodies deposit. 23 sulfate minerals were identified in this work. The results of samples XRD and chemical analysis were furthermore confirmed through thermal, infrared spectrum and mössbauer spectrum analysis. Among those, nine minerals as Ferricopiapite, Cuprocopiapite, Rhomboclase, Parabutlerite, Krausite, Yavapaiite, Metasideronatrite Kroehnkite and Paracoquimbite were founded in China for the first time. And Paracoquimbite was secondly reported in the world (first case reported at 1938 in Chile). 4. EPMA analysis shows that Al impurity in crystal lattice is important to polytype formation of paracoquimbite and coquimbite besides stack fault. 5. Compared with Meiling Cu-Au deposit in the same Kalatage ore belt from the characteristics of δ34S of barite, lithofacies, hydrothermal alteration and homogeneous temperature, Hongshan Cu-Au deposit belongs to the same metallogenic system of HS-epithermal type as Meiling Cu-Au deposit. But Hongshan Cu-Au deposit has less extensive alteration and shallower denudation. 6. Sulfur isotope analyses show that δ34S values of pyrites vary in the range of +1.86‰~+5.69‰, with an average of 3.70‰, mostly in the range of +1.86‰~+3.20‰, and δ34Scp<δ34Spy. Therefore ore-forming fluid of porphyry comes from mantle and was contaminated by the earth’s crust. Sulfur isotope has reached balance in ore-forming process. 7. Sulfur isotope analyses show that δ34S values of sulfates vary in the range of +2.15‰~+6.73‰, with an average of +3.74‰, mostly equals as δ34S values of primary sulfides in Hongshan Cu-Au deposit. So supergene sulfates inherit sulfur of primary sulfide. δ34S values are mostly same in different sulfates. As well as pyrite and chalcopyrite, volcanic hot spring and associated native sulfur underground also provide water medium and sulfur during the formation process of sulfate. 8. According to the EPMA of sample chalcopyrite and pyrite in Hongshan Cu-Au, the value of Cu/Ni is 0.98-34.72, mostly close to the value of 5, which shows that Hongshan deposit is a typical volcanogenic magmaic hypothermal deposit. Au and Ag, Zn, Te and Bi are positive correlation, Cu and Hg, Se, Sb are positive correlation, indicates Au and Cu don’t locate in the factor of mineralization of same mineralization groups. The reasons of gold concentration in the oxidation zone are: 1). Change of redox potential (Eh) makes gold to deposit from the liquid of mineralization zone; 2). PH is one of the most factors of gold’s deposition; 3). Soluble complex and colloid of gold can be adsorbed easily. 9. The biotite and hornblende K-Ar isotopic ages from the wall rock-quartz diorite, biotite granite and monzonite granite are 231.99±3.45Ma, 237.97±2.36Ma and 296.53±6.69Ma respectively. The ore-bearing rhyolitic breccia lava contains breccia of the biotite granite which indicates the volcanism and related Cu-Au mineralization occurred later than the granite, possibly in Mesozoic. K-Ar ages of granitoids in Sanya, Baishiquan and Hongliugou area and Molybdenite Re-Os age of Baishan Mo deposit all are in Triassic. Besides late Paleozoic magmatism, igneous magmatic event of Mesozoic was widespread in eastern Tianshan. 10. The K-Ar age dating indicates that the K-Ar age of Voltaite occurred below surface 1m is 56.02±3.98Ma, K-Ar age of Ferricopiapite occurred below surface 1.5m is 8.62±1.12Ma, K-Ar age of Yavapaiite occurred below surface 14 m is 4.07±0.39Ma, and K-Ar age of Voltaite occurred below surface 10 m is 14.73±1.73Ma. So the age interval of oxidation zone of Hongshan copper-golden bed is between 60 -3.38Ma. Oxidization occurred at Caenozoic era (from 65Ma), which can be identified through comparing with different deposits oxidation zone in other countries. The coupling between global tectonic event and climatic change event which occur from Caenozoic era has some effect on epigeosphere system, which can act on the surface of bed oxidation zone similarly. It induces that the age mentioned above coincide with collision of India-Asia and multistage uplifting of Qinhai-Tibet Plateau happened subsequently. Bed oxidation zone is the effect and record of collision and uplifting of Tibet Plateau. The strong chemical weathering of surface accumulation to which was leaded by PETM event occurred Paleocene and Eocene is the reason of Voltaite sharply rises. On the contrary, Ferricopiapite formed due to the global cold weather. The predecessor did much research through biota, isotopes, susceptibility, but this paper try to use different sulfate mineral instead of climatic change. So the research of sulfate minerals not only indicates a great deal of oxidized zone feature, but also the intergrowth of sulfate minerals may be used to trace paleoenviroment and paleoclimate of oxidation zone. 11. Analysis of the information of alteration and mineralization features of four bore cores, induced activity polarization well logging and Eh-4 geophysical section, deep mineralization anomaly objects of Hongshan ore districts shows low resistance, middle and high polarization, measurements of Eh-4 consecutive conductance section show the existing of concealed porphyry ore body deeper than 450m, on the top of and around rock body there are low resistance body ranged from 100-300Ω•m, this area may be the ore-bearing part. In a word, Hongshan Cu-Au deposit deposit is a combine of upper HS-style epithermal Au deposit and deeper porphyry mineralization system. It has great potential to find large HS-style epithermal-porphyry Au-Cu deposits. This paper consists of seven chapters and twenty seven sections. The geological character of deposit is basic condition in this work. Constitute of oxidation zone, research of sulfate mineral, relation between oxidation and primary zone, K-Ar ages of potassic sulfate are key parts of thesis. Genesis of ore deposit is the further expansion of this research. Analysis of ore-controlling factors is the penetration above basic. Analysis of potential is application of exploration.