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Physiological data from extreme habitat organisms during stresses are vital information for comprehending their survival. The intertidal seaweeds are exposed to a combination of environmental stresses, the most influential one being regular dehydration and re-hydration. Porphyra katadai var. hemiphylla is a unique intertidal macroalga species with two longitudinally separated, color distinct, sexually different parts. In this study, the photosynthetic performance of both PSI and PSII of the two sexually different parts of P. katadai thalli during dehydration and re-hydration was investigated. Under low-grade dehydration the variation of photosystems of male and female parts of P. katadai were similar. However, after the absolute water content reached 42%, the PSI of the female parts was nearly shut down while that of the male parts still coordinated well and worked properly with PSII. Furthermore, after re-hydration with a better conditioned PSI, the dehydrated male parts were able to restore photosynthesis within 1 h, while the female parts did not. It is concluded that in P. katadai the susceptibility of photosynthesis to dehydration depends on the accommodative ability of PSI. The relatively lower content of phycobiliprotein in male parts may be the cause for a stronger PSI after severe dehydration.

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本文从牙鲆中克隆到其肌肉调节因子myogenin和MRF4的基因,并对它们的表达、启动子活性及功能进行分析。 研究结果表明牙鲆myogenin和MRF4都由三个外显子和两个内含子组成,其cDNA编码的氨基酸序列分别与几种鱼类的同源基因亲缘关系较近。 原位杂交显示最早在胚胎5-6个体节时体节中部的细胞检测到myogenin的表达,随着发育的进行,它的表达向体节两侧和体后延伸,最后在整个体节表达。当发育到30个体节的时候,在躯干的表达迅速下降,只在胚胎的尾部能检测到信号。 RT-PCR的结果显示,MyoD和Myf5的表达要早于myogenin,而MRF4的表达晚于myogenin,并且myogenin、MRF4只在成鱼的肌肉中表达,这进一步证明其在肌肉发育过程中的作用。 myogenin和MRF4的启动子中含有保守的肌肉特异调控序列,瞬时表达分析的结果证实两段启动子序列足以驱动GFP在斑马鱼胚胎肌肉中的特异表达。首次对鱼类MRF4启动子进行了调控序列的分析,发现在启动子的-181到-506的序列中含有调节MRF4表达的必需位点。 首次应用原核表达系统对MRF4蛋白进行重组表达,并利用纯化的重组蛋白制备多克隆抗体,通过western杂交分析显示所得到的MRF4多克隆抗体能够识别牙鲆内源性的MRF4蛋白。

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以馆养北太平洋宽吻海豚为研究对象,在海豚馆和水族馆等场所开展了大量的现场实验和行为学研究;通过出海考察、“调查卡”统计、整理历史资料等方式,总结了中国海洋哺乳动物的资源现状,并对我国典型海域中的海洋哺乳动物标本通过目前较为先进的中子活化(INAA)等技术进行了一系列的分析研究。主要结果如下: 1通过对海豚馆的先后10头海豚进行的长达5年的现场实验,首次提出并建立了适合海豚生长的水质标准体系,其中,盐度范围是29-32,PH值范围是7.8-8.2,氯浓度范围是0.3—1.5mg/L,溶解氧范围为5.0—8.8×10~(-6),大肠菌群不超过200MPN等等,这为国内各地海兽馆中的海兽饲养提供了参照标准,为我国海兽饲养业的发展提供了可靠的基础资料。2 通过对海豚的每一批饵料鱼体营养成分的测定分析(粗蛋白、粗脂肪、灰分、水分和总细菌数),进而通过对海豚的食性、日食量及食前反应、食后反应等方面的研究,发现了海豚的季节性饮食喜好规律,即海豚在冬天喜欢采食鲐鱼等高能量型鱼类,在夏天喜1欢采食带鱼等低能量型鱼类,首次建立了海豚的饵料投喂、营养补充物质的适量添加及定期进行驱虫、接种疫苗和体格检查等科学饲养管理方法体系。3通过对北太平洋宽吻海豚进行的500余头次的生理指标的测定(直接获得有关数据9000多个),在国内首次建立了多头宽吻海豚的生理指标档案和数据库,主要包括血常规指标、血液生化指标、体温、呼吸频率等45个指标。4在宽吻海豚生理指标档案和数据库基础上,运用了适当的计算方法,结合相应的生理学意义,统计归纳出了宽吻海豚各生理指标的正常阈值和范围,如白细胞的正常阈值为3.797×10~9个/L-11.56×10~9个/L等等,此生理指标阈值范围体系是准确了解海豚机体的生理状况、疾病诊断及治疗的关键依据。5 发现了海豚各生理指标间的相关关系及生理指标与海豚疾病诊断间的关系规律,基本形成了宽吻海豚常见疾病的诊断和防治方法体系,如海豚血液指标中的K~+值降低,白蛋白与球蛋白比值 (A/G)下降,表明海豚机体脱水,电解质代谢紊乱;海豚血液中 的谷草转氨酶、谷丙转氨酶大幅升高,中性粒细胞值上升,胆红素值升高,表明海豚的肝脏功能异常等等。其中,治愈铜绿假单孢菌感染经查新属国际领先水平。6 总结了中国海洋哺乳动物的资源现状,并通过中子活化技术、等离子体耦合原子发射谱技术和原子发射谱技术,对日本下关海豚、秦皇岛海豚、莱州湾海豚和秦皇岛江豚的肌肉、肝脏、肾脏、心脏和肺等样品进行了多元素的测定分析,测出了其中的27种元素的含量,初步建立了中国海洋哺乳动物环境标本库。7 通过对所测海洋哺乳动物器官样品中的元素含量的比较,发现海洋哺乳动物的不同器官富集元素的能力明显不同,各器官的富集能力基本是肝脏 > 肾脏 > 心脏 > 肺 > 肌肉,海兽肌肉不适合作为环境标本库的样品,而肝脏和肾脏较为适合作为海洋哺乳动物环境标本库的样品。8 所测海兽器官样品中的大多元素的含量值与阿拉斯加环境标本库的结果相似,只有Zn、Cu、Pb和Hg的含量远远高于阿拉斯加环境标本库的结果,而与中国人体肝脏的相应元素的含量基本相似。日本下关海豚肝脏中的Cd、Co、Cr、Cu、Pb、V和Zn元素的含量高于秦皇岛海豚和莱州湾海豚肝脏中对应元素的含量,而秦皇岛海豚肝脏中的As、Cu、和Ni的含量又高于莱州湾海豚肝脏中的相应元素的含量。

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用环磷酰胺(Cy)制造小鼠免疫功能抑制模型,以口服扶正女贞素片的小鼠为阳性对照组,试验组小鼠连续口服耗牛血清IgG,10d后测定小鼠免疫水平的变化。结果,口服牦牛血清IgG的小鼠,抗Cy引起的免疫器官萎缩效果极显著(P<0.01),抗Cy引起的小鼠血清IgG含量降低(P<0.05),能提高小鼠血清IgG水平(P<0.05);牦牛血清IgG对小鼠急性毒性试验属无毒级。证明口服牦牛血清IgG能显著提高小鼠的免疫功能。

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本文介绍了基于工业以太网的深海载人潜水器控制系统的组成原理,描述了控制系统的主要功能、硬件系统和软件流程.在实验室的半物理仿真平台上进行了整个控制系统的功能实验,实验结果证明了基于工业以太网的控制系统可以满足载人潜水器控制系统的需要,运行效果良好。

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泥河湾组含有孔虫化石层位的沉积环境问题存在很大争议。本文从生物壳体的锶同位素地球化学特征对其中的有孔虫进行了进一步研究。样品采自泥河湾小渡口剖面27,28层的有孔虫化石(NonionshansiensisWang)和与其共生的介形虫和腹足类。同时,对该剖面22层介形虫以及流经该剖面的桑干河和支流壶流河河水的87Sr/86Sr值也进行了测定。结果表明,有孔虫壳体87Sr/86Sr值为0.71190~0.712018,介形虫壳体为0.710612~0.711481,腹足类碎片为0.710299~0.712057,壶流河为0.709960,合流前桑干河为0.711721,合流后桑干河为0.711508,22层介形虫壳体为0.710564~0.714240。同层位的有孔虫与介形虫、腹足类的87Sr/86Sr值相互重叠,显示出具有相近或相同银同位素组成的特点,证明他们具有相同的宿生水体。有孔虫壳体的锶同位素组成与陆相的22层介形虫壳体以及现代桑干河河水的87Sr/86Sr值相互重叠,说明当时有孔虫生活在内陆环境。以同时代海水的Sr含量(8×10-6)和87Sr/86Sr值(0.709147)为海水端员,合流后的桑干河的...

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老挝南部Champasak省东北部Boloven高原玄武岩喷发于晚中生代.新生代,在长期热带季风型气候和热带季雨林植被条件下,高原玄武岩上已经发育砖红壤型风化壳。在一条风化壳剖面上采集了11件样品并在室内细碎到200目,使用X射线荧光光谱仪分析了11个样品中的主量元素含量,使用ICP-Ms分析了11件样品REE含量。结果表明,玄武岩风化壳中主量元素Na2O和MgO淋失量最大,K2O和CaO淋失量次之,并在淋失一定程度后淋失速度减慢;样品LR157和LR158中TiO2,P2O5分别为6.07%,1.45%和8.43%,0.82%,为整个剖面中的最高值;CaO的含量是松散风化产物中的最高值。风化玄武岩(LR140,LR141)的∑REE较低,为57.8×10^-6和87.9×10^-6;随着玄武岩风化程度和成壤作用的加强,∑REE逐渐富集,并在风化壳表土下(LR157,LR158)达到最高值1003×10^-6和775×10^-6。风化壳中LREE/HREE值为3.59~14.9,稀土元素分布型式属轻稀土富集型。随着风化程度加深,ce由弱负异常逐渐变为强正异常,而Eu由弱正异常逐渐变小并呈现出强负异常,整个剖面中ce正负异常和Eu正负异常的变化幅度较大。REE在剖面中的分布与含TiO2,P2O5的矿物有明显的相关关系,并且在TiO2,P2O5含量最高的样品LR157和LR158中最为富集。REE富集和Ce正异常出现在pH值为5.23~6.12的酸性和Fe^2+/Fe^3+为0.007~0.13的氧化环境下,证明在酸性氧化环境也能出现REE富集.

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云南会泽铅锌矿床位于扬子板块西缘川-黔-滇铅锌银多金属成矿域的中南部,严格受断裂带的控制.长期以来,对于该矿的成矿流体来源存在着较大的争论.研究表明,矿石中脉石矿物方解石的C、O同位素组成相对均一,其δ^13C(PDB)为-2.1×10^-3~-3.5×10^-3极差-1.4×10^-3、均值-2.8×10^-3,δ^18O(SMOW)为16.7×10^-3~18.6×10^-3、极差1.9×10^-3、均值17.7×10^-3,不同矿体(不同标高)、不同产状以及相同矿体不同产状方解石的C、O同位素组成不具明显差别;除了纯液相包裹体(L)和富液相的气液两相包裹体(L+V)外,还存在含子晶的三相包裹体(S+L+V)和不混溶的CO2三相包裹体(VCO2+LCO2+LH2O),流体包裹体均一温度介于110~400℃之间,具有双峰现象;矿床的(^87Sr/^86Sr)0(0.713676-0.717012)不仅明显高于地幔(0.704±0.002)和峨嵋山玄武岩(0.703932~0.707818;85件样品)的(^87Sr/^86Sr)0,也相对高于矿区赋矿地层(C16)的(^87Sr/^86Sr)。(0.70868~0.70931;3件样品),但明显低于基底岩石的(^87sr/^86Sr)。(0.7243~0.7288;5件样品),且成矿过程中流体基本没有发生Sr同位素分馏现象.因此,成矿流体为均一流体,是不同性质流体的混合产物,具有多源性.而从气液两相包裹体盐度-均一温度图解可以看出,在300-400℃区间,包裹体盐度基本被孤立为两群:一群为5%~6%(w(NaCl)),另一群为12%~16%(w(NaCl)).而在100300℃特别是150-250℃区间,包裹体盐度则基本均匀分布在7%~23%(w(NaCl))之间.断裂带形成压力为(50~320)×10^5Pa,矿体上覆岩石压力为(574-640)×10%5Pa,矿床成矿压力为(145-754)×10^5Pa.流体在上升到断裂带后压力的剧降,导致了沸腾作用的发生.在混合作用和沸腾作用的双重影响下,受狭窄断裂带控制的成矿流体高度浓缩,金属矿物得以大规模地从流体中沉淀出来,形成品位极高的铅锌矿石.

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白牛厂矿床是超大型银多金属矿床,除银储量(>7000t)达到超大型规模外,铅、锌、锡储量均达大型规模,同时伴生大量的分散元素(In、Cd、Ge、Ga等)。矿床位于滇东南个旧和都龙矿田之间,赋存于华南加里东褶皱系滇东南褶皱带西北缘的中寒武统细碎屑岩系之中,北西面以弥勒断裂与扬子地块分界,南西以红河断裂为界与哀牢山断块毗邻,南连越北古陆,东部文麻断裂与南岭褶皱系连为一体,区内地质构造、岩浆活动和矿化作用均较复杂,各构造单元的构造演化对白牛厂银多金属矿床均有不同程度的影响。 白牛厂银多金属矿床自80年代后期被发现以来,已有多家单位和个人在该区开展了一系列的研究工作。但是,在成矿物质及流体来源、矿床成因、矿床与花岗岩的关系等方面都存在诸多争议。本文在深入细致的野外地质工作基础上,对矿石进行了系统的显微镜鉴定,并对部分矿物做了电子探针定量及面扫描分析,详细研究了矿床成矿元素特征及主量元素、微量元素、稀土元素、同位素地球化学特征,主要取得以下结论性成果: 1. 银矿物的赋存状态及形成阶段。银主要以硫盐或复硫盐矿物的形式出现,方铅矿是主要的载银矿物。原生银矿物明显分为两组:一组为Ag的黝铜族矿物和Ag的锑硫盐矿物,产于方铅矿的内部或与方铅矿连生形成文象状连晶,与方铅矿具有相似的物源,属热水沉积成因;另一组为Ag的锡硫盐矿物,产于方铅矿边部,往往伴随锡石、黄锡矿、辉锑锡铅矿产出,可见黄锡矿交代锡石形成镶边结构,暗示了其岩浆热液成因。 2. 花岗岩特征及其与成矿的关系。白牛厂矿区花岗岩具有富硅、富碱及高钾低钠特点,属铝过饱和钙碱性岩,与花南改造型花岗岩相似,属同碰撞S型花岗岩,成岩物源主要是基底变质岩重熔作用形成的花岗岩浆,Ag、Pb、Zn、Sn等成矿元素含量较高;与矿石稀土元素对比研究表明,花岗岩稀土配分模式与矿区东南部穿心洞、对门山和阿尾矿段矿石相似,而与矿区西北部白羊矿段矿石相差较大,暗示后期岩浆叠加改造作用主要发生在矿区东南部诸矿段。   3. 矿床含矿沉积建造地球化学特征。通过与中国大厂、个旧典型热水沉积硅质岩,加拿大沙利文矿山的条带状富电气石热液沉积岩和加拿大Agnico-Eugle矿山的铁建造中的条带状燧石岩以及现代海底热水沉积物对应的主量元素、微量元素及稀土元素对比研究,为白牛厂矿床含矿沉积建造提供了热水沉积成因的地球化学证据,指出该区中寒武世可能发生了广泛的热水沉积事件。   4. 成矿物质及成矿流体来源。系统的铅、硫同位素研究表明,中寒武世热水沉积成矿期金属成矿元素及硫主要是由下地壳古老变质岩淋滤出来的;燕山期花岗岩也在矿区东南部叠加改造较强的部位提供了Sn等部分金属成矿元素及硫。碳、氧同位素及矿石稀土元素反映矿床早期成矿流体源于深部岩浆,晚期主要来源于燕山期花岗岩浆。   5. 矿床分散元素特征。分散元素In、Cd、Ga含量较高,平均含量分别为33.21×10-6、389.8×10-6、10.18×10-6,初步估计该矿床In、Cd、Ga储量分别大于180t、20000t、600t,闪锌矿是分散元素In、Cd、Ga主要的载体矿物。 6. 可能的矿床成因模式。白牛厂银多金属矿床是长期以来多种地质作用综合的产物,具有多来源、多期次成矿特点,经历了广泛且具有重要成矿意义的中寒世热水沉积成矿作用和燕山晚期岩浆热液叠加改造作用,热水沉积成矿作用形成了层状、似层状矿体,燕山期岩浆热液在矿区东南部对矿床强烈叠加改造,白牛厂银多金属矿床应属“热水沉积+岩浆热液叠加改造”成因。

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Robots must successfully plan and execute tasks in the presence of uncertainty. Uncertainty arises from errors in modeling, sensing, and control. Planning in the presence of uncertainty constitutes one facet of the general motion planning problem in robotics. This problem is concerned with the automatic synthesis of motion strategies from high level task specification and geometric models of environments. In order to develop successful motion strategies, it is necessary to understand the effect of uncertainty on the geometry of object interactions. Object interactions, both static and dynamic, may be represented in geometrical terms. This thesis investigates geometrical tools for modeling and overcoming uncertainty. The thesis describes an algorithm for computing backprojections o desired task configurations. Task goals and motion states are specified in terms of a moving object's configuration space. Backprojections specify regions in configuration space from which particular motions are guaranteed to accomplish a desired task. The backprojection algorithm considers surfaces in configuration space that facilitate sliding towards the goal, while avoiding surfaces on which motions may prematurely halt. In executing a motion for a backprojection region, a plan executor must be able to recognize that a desired task has been accomplished. Since sensors are subject to uncertainty, recognition of task success is not always possible. The thesis considers the structure of backprojection regions and of task goals that ensures goal recognizability. The thesis also develops a representation of friction in configuration space, in terms of a friction cone analogous to the real space friction cone. The friction cone provides the backprojection algorithm with a geometrical tool for determining points at which motions may halt.

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Grupo de maturidade; Peso médio de sementes; Mancha "olho-de-rã"; Cancro da haste; Oídio; Nematóides de galhas; Cultivares de soja convencional; BRSGO 7560; BRSMG 752S; BRSGO 7960; BRS 217 [Flora]; BRSMG 68 [Vencedora]; BRSMG 810 C; MG/BR-46 Conquista; BRSGO 8360; BRS Jiripoca; BRSGO Luziâna; BRSGO Chapadões; BRSGO Jataí; BRS Pétala; BRS Gralha; BRS 252 [Serena]; BRS Aurora; BRS Raimunda.

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A gueroba, guariroba ou gariroba e uma palmeira importante para a populacao do Cerrado, sendo extraido dela um palmito de sabor amargo muito apreciado na culinaria regional. Esse produto e comercializado, geralmente, in natura e sua industrializacao ainda e artesanal. Seu principal mercado localiza-se nos Estados de Goias, Tocantins, Mato Grosso, Mato Grosso do Sul, algumas regoes da Bahia e de Minas Gerais e no Distrito Federal. Com a exploracao predatoria e a acelerada destruicao da vegetacao nativa por meio da expansao da fronteira agricola, a oferta do produto, oriunda do extrativismo, vem sendo reduzida substancialmente. No entanto, tem-se observado o cultivo dessa palmeira em alguns Estados, principalmente em Goias que, em 1999, cultivava 4.499 hectares. Neste estudo, encontra-se descrito o sistema de producao da cultura de gueroba, consorciada com milho e feijao, nos dois primeiro anos, bem como a matriz dos coeficientes tecnicos, as estimativas do Custo Operacional Efetivo (COE) e os fluxos liquidos de caixa, referentes a quatro alternativas de producao (gueroba-milho-feijao, laraja-pera-rio, milho e arroz de sequeiro) para um periodo de oito anos. Para comparar as diferentes alternativas de investimento, foi utilizado como principal indicador o Valor Atual Liquido (VAL) que considerando o nivel de preço medio, o valor estimado por hectare foi de R$ 35.599,60 para o consorcio queroba-milho-feijao; de R$ 20.994,74 para a cultura de laranja-pera-rio; de R$ 609,33 para o milho e de R$ (-810,36) para o arroz de sequeiro. Como indicadores-auxiliar, foram utilizados: a relacao beneficio/custo, o preco de equilibrio e a margem bruta. Os resultados indicam que, para as condicoes vigentes de mercado e os niveis de tecnologia considerados, o sistema gueroba proporciona, em todos os niveis de precos, o maior retorno do capital investido e maior relacao beneficio/custo.

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Background: Infection with multiple types of human papillomavirus (HPV) is one of the main risk factors associated with the development of cervical lesions. In this study, cervical samples collected from 1, 810 women with diverse sociocultural backgrounds, who attended to their cervical screening program in different geographical regions of Colombia, were examined for the presence of cervical lesions and HPV by Papanicolau testing and DNA PCR detection, respectively. Principal Findings: The negative binomial distribution model used in this study showed differences between the observed and expected values within some risk factor categories analyzed. Particularly in the case of single infection and coinfection with more than 4 HPV types, observed frequencies were smaller than expected, while the number of women infected with 2 to 4 viral types were higher than expected. Data analysis according to a negative binomial regression showed an increase in the risk of acquiring more HPV types in women who were of indigenous ethnicity (+37.8%), while this risk decreased in women who had given birth more than 4 times (-31.1%), or were of mestizo (-24.6%) or black (-40.9%) ethnicity. Conclusions: According to a theoretical probability distribution, the observed number of women having either a single infection or more than 4 viral types was smaller than expected, while for those infected with 2-4 HPV types it was larger than expected. Taking into account that this study showed a higher HPV coinfection rate in the indigenous ethnicity, the role of underlying factors should be assessed in detail in future studies.