170 resultados para Lamarck


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本文研究了典型有毒赤潮藻——亚历山大藻(Alexandrium)对海湾扇贝(Argopecten irradians Lamarck)、文蛤(Meretrix meretrix Linnaeus)和太平洋牡蛎(Ostrea gigas Thunberg)受精卵孵化的影响和致毒机制以及对蒙古裸腹溞(Moina mongolica Daday)生命活动的影响。此外,还针对我国赤潮发生特点,模拟研究了我国东海大规模赤潮对菲律宾蛤仔(Ruditapes philippinarum (Adams et Reeve))受精卵孵化和蒙古裸腹溞种群数量的影响。 结果发现:8株产PSP毒素的亚历山大藻:塔玛亚历山大藻( ATHK, AT5-1, AT5-3, ATCI02, ATCI03),链状亚历山大藻, A. lusitanicum、微小亚历山大藻和2株不产PSP毒素的相关亚历山藻(AC-1, AS-1)对海湾扇贝受精卵的孵化均有显著抑制作用,说明在亚历山大藻属中,这种抑制作用具有一定的普遍性,并与PSP毒素的产生无直接关系,表明存在非PSP毒素的其它毒性物质。一种PSP标准毒素STX也没有这种抑制作用,进一步证明该抑制作用与PSP毒素不直接相关。 相关亚历山大藻AC-1对海湾扇贝、文蛤和太平洋牡蛎受精卵孵化的有显著的毒害作用,其藻液、重悬液、去藻液和内容物均显著影响受精卵的孵化。相关亚历山大藻AC-1对海湾扇贝、文蛤和太平洋牡蛎担轮幼虫细胞的超微结构有显著破坏作用,破坏膜结构和胞内结构,影响细胞内的功能器官如溶酶体的稳定性,使卵黄颗粒萎缩变形;对文蛤和太平洋牡蛎的受精卵显示出极强的毒害作用: 3000cells•ml-1时,使二者胚胎完全溶掉消失;在2000cells•ml-1的藻液中培养2h后,担轮幼虫的外膜发生溶解,整个幼体呈葡萄串样。相关亚历山大藻AC-1产生的这种毒性物质可能对贝类胚胎细胞的结构和功能有影响。 亚历山大藻对蒙古裸腹溞的毒性效应与不同藻种/藻株密切有关:塔玛亚历山大藻(AT-6, ATCI02)、链状亚历山大藻、A. lusitanicum和微小亚历山大藻不影响蒙古裸腹溞的存活,而塔玛亚历山大藻(ATHK、ATCI03和AT5-1)和相关亚历山大藻(AC-1, AS-1)有显著影响。蒙古裸腹溞能摄食塔玛亚历山大藻(AT-6, ATHK, ATCI02, ATCI03, AT5-1),链状亚历山大藻, A. lusitanicum和微小亚历山大藻,很少或基本不摄食相关亚历山大藻。亚历山大藻影响蒙古裸腹溞的RNA/DNA比值和蛋白质含量以及Na+,K+-ATP酶活性。相关亚历山大藻AC-1对蒙古裸腹溞的存活有极强的毒性作用,藻液、重悬液、内容物和碎片均有显著影响;即使与3×106cells•ml-1小球藻混合,10和50cells•ml-1的相关亚历山大藻AC-1仍能使蒙古裸腹溞的产幼数和存活时间显著下降。亚历山大藻对蒙古裸腹溞生命活动的影响不仅与PSP毒素有关,还与非PSP毒素有关;蒙古裸腹溞可能也是研究有害藻急性和慢性毒性的一种理想生物。 应用菲律宾蛤仔胚胎和蒙古裸腹溞评价我国东海特大规模赤潮对海洋生物资源的潜在危害时发现:单种链状亚历山大藻对菲律宾蛤仔受精卵的孵化和蒙古裸腹溞的种群增长均有显著不利影响;单种东海原甲藻(1~10×104cells•ml-1)对菲律宾蛤仔受精卵的孵化没有影响;较低密度的东海原甲藻能维持蒙古裸腹溞(2~5×104cells•ml-1)的种群增长;较高密度的东海原甲藻对蒙古裸腹溞(10×104cells•ml-1)种群有显著的抑制作用。两种藻以赤潮密度混合后,适当密度的东海原甲藻能在一定程度上减轻链状亚历山大藻对菲律宾蛤仔受精卵和蒙古裸腹溞的毒性。可见,东海连年爆发的大规模赤潮不仅对浮游生态系统有不利影响,若同时爆发亚历山大藻赤潮,则对海洋浮游生态系统和贝类资源的恢复产生更加不利的影响。

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海湾扇贝Argopecten irradian Lamarck于1982年从美国引种到中国,由于具有较快的生长速度和很高的经济效益,海湾扇贝成为中国最主要的养殖贝类之一。近年来海湾扇贝养殖遇到了死亡率高等问题,深入开展海湾扇贝功能基因的研究,尤其是免疫相关基因及其机制研究并在此基础上寻找扇贝疾病防治的有效方法对海湾扇贝的健康养殖十分重要。 对于贝类免疫系统来说,其血细胞在先天性免疫防御中起着重要的作用。当受到外界病原侵染时,贝类血细胞的一个重要免疫反应就是吞噬作用。在吞噬病原过程中,受到病原侵染的贝类还会产生其他多种免疫反应,这些免疫反应将消耗大量的能量(ATP),产能的呼吸链会加速运转,由此也会引发与呼吸链相耦联的活性氧(ROS)的大量产生。这些活性氧具有极强的反应特性,能破坏病原微生物的结构和功能分子,实现对入侵病原的杀灭。利用活性氧对被吞噬的病原进行杀灭,这是吞噬作用消除病原抵御侵染的重要机制。但由于活性氧分子反应的非特异性,它们也会破坏宿主机体细胞内的功能蛋白分子、不饱和脂肪酸分子和核酸等,对细胞造成严重的伤害,进而导致机体生理机能的损伤和免疫系统的破坏。所以,及时消除病原感染机体内过量产生的ROS,维持相关细胞的正常代谢,对提高机体抵抗力和免疫力具有重要的作用。O2-是生物体内产生的第一种活性氧分子,其他的活性氧分子也是由它衍生而来,消除过量O2-是消除过量活性氧危害的第一步也是关键一步。生物体内,超氧化物歧化酶(SOD)是催化O2-发生歧化反应,消除O2-的关键酶。 首先,本文通过RACE方法获得了海湾扇贝SOD家族全部三种基因的cDNA全长并对其进行了序列的生物信息学分析,海湾扇贝AiCuZnSOD全长cDNA为1047个碱基,其中开放阅读框为459个碱基,编码152个氨基酸,与栉孔扇贝Chlamys farreri的CuZnSOD相似度为77.5%,与长牡蛎Crassostrea gigas的相似度为75%,与人的相似度为74.7%。AiMnSOD全长cDNA为1207个碱基,其中开放阅读框为678个碱基,编码226个氨基酸,序列比对结果发现AiMnSOD的氨基酸序列与虾夷扇贝Mizuhopecten yessoensis和皱纹盘鲍Haliotis discus hannai的相似度分别为85%和78.4%,与哺乳动物相似度也在68%~72%之间。AiECSOD全长cDNA为893个碱基,其中开放阅读框为657个碱基,编码218个氨基酸。AiECSOD与其它物种ECSOD相似度比较低。与线虫Brugia pahangi的相似度为27.9%,与疟蚊Anopheles gambiae的相似度为31.4%,与斑马鱼Danio rerio的相似度为27.8%,与人的相似度也只有28.6%,与同是贝类的长牡蛎ECSOD也只有28.1%的相似性。主要原因是AiECSOD的信号肽和肝磷脂结合区域在各物种中无同源性。 其次,采用qRT-PCR(quantitative real time PCR)方法分析三种SOD基因在不同组织中的表达情况,结果表明三种SOD基因的组织表达有所差异。AiCuZnSOD基因在鳃中表达水平最高,其次是血细胞和性腺,在外套膜、闭壳肌和肝胰脏表达水平较低。AiMnSOD基因在鳃中表达水平最高,其次是外套膜,在血细胞、性腺,而在肝胰脏和闭壳肌表达较弱。AiECSOD基因在血细胞中表达水平最高,其次是肝胰脏,在鳃、闭壳肌表达水平较低,而性腺和外套膜没有检测到。同时,采用qRT-PCR对鳗弧菌Vibrio angullarum感染后海湾扇贝血细胞中三种SOD基因mRNA表达变化进行了检测。AiCuZnSOD表达量在各个时间段没有显著差异(P > 0.05)。AiMnSOD的表达量在1.5 h时略有下降,在3 h时达到最高表达量,是空白组(0h)的3倍(P < 0.01),从6 h到24 h表达量逐渐下降,24 h时表达量是空白组的1.6倍,24 h到48 h又稍有升高。AiECSOD的表达量在1.5 h时有所下降,是空白组的0.3倍(P < 0.05),随后逐渐升高,在12 h时达到最高表达量,是空白组(0h)的4.5倍(P < 0.01),从24 h到48 h表达量逐渐下降并恢复到空白组的水平。在对照组,各个时间点没有显著差异(P > 0.05)。在鳗弧菌感染后,海湾扇贝三种SOD的表达并不一致,且差异比较显著。AiCuZnSOD被认为是构成性表达基因,其受外界刺激的影响最小,AiMnSOD和AiECSOD受刺激后表达上调比较明显。 第三,采用Genome-walking的方法得到了海湾扇贝三种SOD基因的基因组全长和近端启动子序列并对其进行了相关分析。AiCuZnSOD的基因组序列全长为4279bp,包含有4个外显子和3个内含子。AiMnSOD的基因组序列全长为10692bp,包含有4个外显子和3个内含子。AiECSOD的基因组序列全长为5276bp,包含有5个外显子和4个内含子。三种基因外显子和内含子的结合处序列遵循-AT/GT-原则。我们把海湾扇贝SOD家族的三个基因的近端启动子进行了比较分析。发现三种SOD在靠近起始密码子的位置都有Oct-1结合位点。三种SOD共有的转录位点有:Oct-1、C/EBPalp、Oct2.1、Sp-1和GATA-1。AiCuZnSOD和AiMnSOD共有的转录位点有:ICSBP、Ftz、TATA-box、C/EBPbeta和Antp。AiCuZnSOD和AiECSOD共有的转录位点有:AP-1和NFκB。AiMnSOD和AiECSOD共有的转录位点有:GR和ER。AiCuZnSOD独有的位点有:SRF、YY-1和NF-1。AiMnSOD独有的位点有:HNF-1、Hb、MEB、NF-muE1、Pit-1a和Eve。AiECSOD独有的位点有:CREB、RATA-alph、Kruppel-like和AP-3。 此外,通过构建原核表达载体,本研究对AiCuZnSOD和AiECSOD基因进行了体外重组表达,并对纯化的重组蛋白进行了酶活分析。酶活分析表明,重组AiCuZnSOD蛋白有较高的酶活和稳定性。 最后,我们对海湾扇贝三种SOD基因的部分区域,包括启动子、编码区,部分内含子区域进行了SNP检测,并对SOD基因部分SNP位点多态性和鳗弧菌敏感性进行了相关分析。三种SOD基因中,我们共发现了59个SNP位点,其中AiECSOD的SNP位点最多,特别是在启动子区,AiCuZnSOD和AiMnSOD多态性较低。其中AiCuZnSOD启动子区的-1739 T-C 位点的基因型和等位基因,AiECSOD启动子区的-498 A-T和-267 G-A等位基因频率,AiECSOD的第一个外显子38 Thr-Lys的多态性在敏感和抗菌群体中存在显著差异(P < 0.05)。

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从1949年以来经过近五十年的发展,超低温保存种质细胞技术已经趋于成熟,特别是在家畜推广良种化的过程中发挥重要作用。对海洋动物种质细胞保存研究的范围主要集中在鲑鳟鱼类和牡蛎等少数几种海洋生物上。本研究结合“国家自然科学基金”研究项目,进行了三种贝类和两种鱼类精子的超低温保存实验,得到了它们在液氮(-196 ℃)条件下的适宜保存条件。栉孔扇贝(Chlamys farreri)冻精解冻后复苏比例、受精率和孵化率最高可达到49.39%、42.06%和12.15睦栉孔扇贝精子超低温保存时发生冷冻伤害的温度范围在-30 ℃~-60 ℃;其低温保存的最适降温速率为20 ℃/min;使用抗冻剂二甲基亚砜(DMSO)的最适浓度为5 ℃,其保存效果优于甘油;样品保存的最佳体积为0.6ml~1ml;解冻精子的最适水温为35 ℃,50 ℃次之,20 ℃最差;用自然海水激活解冻后精子的效果好于低盐度溶液;在0 ℃进行预处理平衡时间不宜太长;在抗冻液中加入蛋黄对保存效果没有改善,并且会对冻精的孵化率有抑制作用;用20 ℃/min和5%DMSO冷冻精子,液氮中保存栉孔扇贝精子55天后其复苏比例达到42.17%。超低温保存紫贻贝(Mytilus galloprovincialis Lamarck)精子,解冻后其复苏比例、受精率和孵化率最高可达到41.63%、69.52%和54.74%。保存紫贻贝精子最适降温速率为5 ℃/min,发生冻伤的温度范围是-20 ℃~-60 ℃;使用抗冻剂DMSO的保存效果好于甘油,且使用抗冻剂DMSO的最适浓度为15%;利用自然海水激活冻精效果好于低盐度或高pH值的溶液;样品体积(在0.2~1ml之间)对保存效果没有影响;采用15%DMSO和5 ℃/min的降温速率处理精子,液氮中保存90天后复苏比例仍达到41.8%。保存菲律宾蛤仔(Ruditapes philippinarum (Adams and Reeve))精子的最适降温速率为5 ℃/min,发生冻伤的温度范围是-30 ℃~-60 ℃;抗冻剂DMSO的保存效果好于甘油,也用DMSO与甘油混合使用,使用抗冻剂DMSO的最适浓度为10%;利用自然海水激活冻精效果好于低盐度或高pH的溶液;样品体积(在0.2%~1.6ml之间)对保存效果有显著影响。冷冻保存后精子复苏比例、受精率和孵化率最高达到40.84%、68.87%和47.17%;以最适降温速率和抗冻剂浓度处理精子,并在液氮中保存36天后冻精复苏比例仍可以达到38.54%。黑鲷(Sparus macrocephalus)精子经过超低温保存后复苏率、存活率最高可以达到61.37%和61.4。保存黑鲷精子时发生冷冻伤害的温度范围是-20 ℃~-60 ℃,适宜的降温速率为20 ℃/min;使用抗冻剂DMSO的适宜浓度为20%;样品体积对保存效果有相关性;利用自然海水激活冻精效果好于低盐度或高pH值的溶液;使用20%DMSO和20 ℃/min降温速率处理,在液氮中保存黑鲷精子66天后解冻,其复苏率和存活率分别为59.81%和58.45%。在液氮中保存真鲷(Pagrosomus major)精子时发生冷冻伤害的温域为-30 ℃~-60 ℃,适宜的降温速率为20 ℃/min;使用抗冻剂DMSO的适宜浓度为20%;采用低盐度或高pH值的溶液激活冻精的效果不如自然海水。真鲷冻精的复苏率和存活率最高可达到50.73%和62.5;以20 ℃/min和20%DMSO处理真鲷精子,保存在液氮中46天后冻精复苏率和存活率为50.63%和61.02%。通过对多种贝类和鱼类精子的超低温保存实验,不仅获得超低温保存基本条件,并且通过显微镜观察结合前人的研究,对产生冻伤的原因和保护的机理提出了一个模式。

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The impacts of Prorocentrum donghaiense Lu and Alexandrium catenella Balech, causative species of the large-scale HAB in the East China Sea, were studied under laboratory conditions. According to bloom densities, the effects of monoculture and mixture of the two species were examined on the egg-hatching success of Argopecten irradians Lamarck, and the population growth of Brachionus plicatilis Muller and Moina mongolica Daday. The results showed that monoculture of A. catenella had a significant inhibition on the egg hatching success of A. irradians, and the population growth of B. plicatilis and M. mongolica. The median effective densities ( EDSo) inhibiting the egg hatching success of A. irradians for 24 h and the population growth of B. plicatilis and M. mongolica for 96 h were 800, 630, and 2 400 cells/cm(3), respectively. Monoculture of P. donghaiense has no such inhibitory effect on the egg hatching success of A. irradians; P. donghaiense at lower suitable densities could sustain the population growth of B. plicatilis (1 x 10(4) similar to 3 x 10(4)cells/cm(3)) and M. mongolica (2 x 10(4) similar to 5 x 10(4) cells/cm(3)); P. doaghaiense at higher densities had significantly adverse effect on the population growth of B. plicatilis (4 x 10(4) similar to 10 x 10(4) cells/cm(3)) and M. mongolica (10 x 10(4) cells/cm(3)). When the two algae were mixed according to bloom densities, P. donghaiense at suitable densities to some extent could decrease the toxicity of A. catenella to B. plicatilis and M. mongolica. The results indicated that the large-scale HAB in the East China Sea could have adverse effect on zooplankton, and might further influence the marine ecosystem, especially when there was also Alexandrium bloom.

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Arcellacea (testate lobose amoebae) are important lacustrine environmental indicators that have been used in paleoclimatic reconstructions, assessing the effectiveness of mine tailings pond reclamation projects and for studying the effects of land use change in rural, industrial and urban settings. Recognition of ecophenotypically significant infra-specific ‘strains’ within arcellacean assemblages has the potential to enhance the utility of the group in characterizing contemporary and paleoenvironments. We present a novel approach which employs statistical tools to investigate the environmental and taxonomic significance of proposed strains. We test this approach on two identified strains: Difflugia protaeiformis Lamarck strain ‘acuminata’ (DPA), characterized by fine grained agglutination, and Difflugia protaeiformis Lamarck strain ‘claviformis’ (DPC), characterized by coarse grained agglutination. Redundancy analysis indicated that both organisms are associated with similar environmental variables. No relationship was observed between substrate particle size and abundance of DPC, indicating that DPC has a size preference for xenosomes during test construction. Thus DPC should not be designated as a distinct strain but rather form a species complex with DPA. This study elucidates the need to justify the designation of strains based on their autecology in addition to morphological stability.

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Contient : 1 Lettre du roi « FRANÇOYS [Ier]... au sire d'Izernay,... A Lyon, le XXIIIe jour de juillet mil V.C.XXXVI » ; 2 Lettre de « CHARLES », duc de Savoie, au « roy... A Chambery, le IIe de novembre » ; 3 Lettre d'«ANTHOINE [duc DE LORRAINE]... à monseigneur le grant maistre... A Nancey, le XVe de mars » ; 4 Lettre de « CHARLES [DE BOURBON, duc DE VENDOME]... à... monseigneur le mareschal de Montmorency,... A Abeville, le XXe jour de juing » ; 5 Lettre de « P. DE VILLERS L'YLE ADAM,... à monseigneur le grand maistre... De Paris, ce IIe jour de mars » ; 6 Lettre de « ROBERT DE LAMARCK,... à monseigneur le grant maistre... De Braye, ce IIe novembre » ; 7 Lettre de « A. DE BOYSY » et « D'INTEVILLE,... à monseigneur le grant maistre... De Bloys... mars » ; 8 Lettre de « BRYSAY,... au roy... A Dijon, ce VIe de may » ; 9 « Instruction sommaire des droictz, noms, raisons et actions pretendues respectivement sur le marquisat de Montferrat, tant par Charles, nagueres duc de Savoie, duc et duchesse de Mantue, le feu Françoys, marquis de Saluces, que par le roy » ; 10 Lettre du gouverneur de Fontarabie « al... señor mayordomo mayor del christianisimo rey de Francia... De Fuentarrabia, a II de julio » ; 11 « Gentilxhommes, dames, damoiselles et autres officiers de la maison de feue Madame, mere du roy, que ledict seigneur veult et entend pourveoir en la forme qu'il s'ensuit » ; 12 Lettre de « POT,... à monseigneur le conestable... De Londres, ce XVIIIe jour de mars 1550 » ; 13 Lettre de « DE LALAING,... à monseigneur de La Pommeraye,... D'Utrecht, le XIXe de fevrier l'an XXIX » ; 14 Lettre de « ROBERT DE LAMARCK,... à monseigneur le grant maistre... De Chasteau Thierry, ce XXIe jour de janvier » ; 15 Lettre d'« HUMYERES » et DE « SAINCT ANDRE,... à monseigneur le grant maistre... De Sainct Jehan d'Angely, ce jour Nostre Dame... » ; 16 Lettre de « JEHAN [STUART, duc D'ALBANY]... à monseigneur le grant maistre... De Paris, ce dernier jour d'octobre » ; 17 Lettre de « RENE DE COSSE,... à monseigneur le grant maistre... A Burgues, ce XXIXe jour d'aoust » ; 18 Lettre de « RENE DE COSSE,... à monseigneur le grant maistre... De Tuyrs pres Lagrueble, ce Xe de juing » ; 19 Lettre de « SAINT ANDRE,... à monseigneur le grant maistre... De Villefranche en Beaujeuloys, le XVIIe decembre » ; 20 Lettre d' « HUMYERES, SAINT ANDRE, RENE DE COSSE,... à mons le grant maistre... De Sainct Denys, ce VIIIe jour de fevrier » ; 21 Lettre de « SAINT ANDRE,... à monsieur le grant maistre... A Sainct Germain en Laye, ce IXe de mars » ; 22 Lettre de « SAINT ANDRE,... à monsieur le grant maistre... A Saint André, ce IIe jour de may » ; 23 Lettre de « SAINT ANDRE » et « RENE DE COSSE,... à monseigneur le grant maistre... A Suzaine, ce XXVIIe may » ; 24 Lettre de « SAINT ANDRE,... à monsieur le grant maistre... A Bayonne, ce XIXe jour d'octobre » ; 25 Lettre de « RENE DE COSSE,... au roy... A Villepende, le sixiesme jour de mars » ; 26 Lettre de « RENE DE COSSE,... à monseigneur le grant maistre... De Brissac, ce XVe d'aoust » ; 27 Lettre de « RENE DE COSSE,... à monseigneur le grant maistre... De Jarnac, ce samedi... » ; 28 Lettre de « RENE DE COSSE,... à monseigneur le grant maistre... De Quintane pres Gonnyet du Sang, ce XXIIIe d'avril » ; 29 Lettre de « RENE DE COSSE,... à monseigneur le grant maistre... De Burgues, ce dernier jour de septembre » ; 30 Lettre de « RENE DE COSSE,... à monseigneur le grant mestre... A Bayonne, le XXVIe d'avryl » ; 31 Lettre de « RENE DE COSSE,... à monseigneur le grand maistre... De Quintane, ce XXe avril » ; 32 Lettre de « RENE DE COSSE,... à monseigneur le grant maistre... De Quintane, ce Xme may » ; 33 Lettre de « SAINT ANDRE,... à monsieur le grand maistre... A Bayonne, ce XXVIIe jour d'octobre » ; 34 Lettre de « SAINT ANDRE,... à monseigneur le grant maistre... De Lyon, ce XVe decembre » ; 35 Lettre de « RENE DE COSSE,... à monseigneur le grant maistre... De Bloys, ce lundy... » ; 36 Lettre de « SAINT ANDRE,... à monseigneur le grant maistre... De Sainct André, ce XXIIIe decembre » ; 37 Lettre de « MAXIMILIAN,... à monseigneur le grand maistre... De Poyssi, ce jeudy... » ; 38 Lettre de « TURENNE,... à monseigneur le grand maistre... De Mirande, ce IIIe d'avrilh » ; 39 « Double de la lettre que monseigneur le viconte DE TURENNE a escripte à monseigneur le grant maistre... De Victoire, ce VIIe jour de may » ; 40 Lettre de « SAIGUES,... ambassadeur de Portugal », au grand maître de France. « A Lisbonne, le XVIIIe jour de janvier » ; 41 Requête adressée « à la royne » par « les manans et habitans de la ville d'Angers », pour qu'elle vienne en aide à ladite ville ; 42 Mémoire en latin sur la rançon du roi François Ier. Copie ; 43 Avis donné de Rome, « du XXe avril V.C.XXIX », par le cardinal de SAINT SEVERIN à son frère ; 44 « Dames et damoiselles de la maison de la royne Eleonor que le feu roy faisoit payer, chacun an, en l'espargne, de leurs gaiges et charroy » ; 45 « Double du povoir du herault d'Angleterre », délivré par Marie, reine d'Angleterre, à Westminster, le premier juin 1557. Copie latine ; 46 Requête, en allemand, présentée au roi François Ier, en faveur de Wilhelm, comte de Furstemberg. 1541 ; 47 État de payement de troupes ; 48 Dépêche adressée par « ROBERTET » à un ambassadeur, sur la délivrance des enfants de France ; 49 Lettre de « D'ANGERANT » et « MORELET,... au roy... A Lucerne, le XVIe de febvrier » ; 50 Lettre de « MORELET,... à monseigneur le grant maistre... De Lucerne, ce jour Sainct Michel, penultime de septembre » ; 51 État des « vivres necessaires pour l'armée de mil hommes d'armes et vingt mil hommes de pied » ; 52 « Memoire pour monseigneur le grand maistre touchant les affaires de madame l'archeducesse et aultres » ; 53 Nouvelles d'Espagne ; 54 Nouvelles d'Allemagne

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Estudio sobre la evolución del concepto de biología, a través de distintos sistemas filosóficos. Se parte de la definición etimológica de biología, que deriva del griego bios, que significa vida; y logos, cuya traducción es tratado, discurso; o sea, tratado sobre la vida en general. La palabra Biología fue introducida en el lenguaje científico simultáneamente por Lamarck y Treviranus en el año 1802. Desde entonces ha constituido una rama de las Ciencias Naturales. Se analiza la relación de la Biología con otras ciencias afines, y se establecen una serie de características comunes al objeto de estudio de la biología, es decir, los seres vivos. Por otro lado se traza una panorámica de la historia de la Biología a través del tiempo. Se considera a Hipócrates como el primer biólogo que registra la historia, hacia el año 460 antes de J. C. Perteneció a la escuela griega de Coos. También se hace referencia a otros intelectuales griegos, como Aristóteles, que fue el primero que estudió como distintas ramas de las Ciencias Biológicas, la Zoología, Botánica, Embriología, Fisiología, e incluso Anatomía comparada. Posterior a Aristóteles es Plinio, que escribió 37 libros sobre Historia Natural, siendo considerado por muchos como el fundador de esta ciencia. De otras épocas históricas, se hace especial mención al Renacimiento, y su tendencia al individualismo y el humanismo. Se destacan los nuevos conceptos que aportan a la Biología Vesalio, Leonardo de Vinci y Paracelso, Miguel Servet y Harvey. Siguió a esta época un concepto de la Biología denominado mecanicista; es la época de Bacon, Galileo y Descartes, denominada cartesiana, que propuso un nuevo método científico en contra de la filosofía antigua y rechazando la Escolástica. Con él prosperan todas las ciencias en general. Ya en el siglo XVIII, Linneo, da un gran impulso a las Ciencias Naturales, con su obra Sistema Natural, en la que los tres grandes reinos de la naturaleza, aparecen divididos en clases, órdenes, familias y especies. Posteriormente, este gran esfuerzo de la Sistemática, ha tendido a menospreciarse en favor de otras disciplinas consideradas como más nobles, como la Anatomía, o la Fisiología. Otro hito de gran importancia lo situamos en 1859, cuando Darwin publica El origen de las especies, en la que expresaba su nueva concepción del origen de la vida. También se menciona a Mendel, autor de las célebres leyes sobre la herencia, que marcó el inicio de la actual ciencia conocida con el nombre de Genética. Por último, se mencionan algunos de los españoles más ilustres en el campo de la biología y sus principales aportaciones a su desarrollo.

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The tarantula genus Ephebopus Simon 1892 is reviewed and includes the type species, E. murinus (Walckenaer 1837), and E. uatuman Lucas, Silva & Bertani 1992, E. cyanognathus West & Marshall 2000, E. rufescens West & Marshall 2000 and Ephebopus foliatus, sp. nov., from Guyana. Ephebopus violaceus Mello-Leitao 1930 is transferred to Tapinauchenius Ausserer, where it is a senior synonym of Tapinauchenius purpureus Schmidt 1995 new synonymy. Ephebopus fossor Pocock 1903 is considered a nomen dubium. Ephebopus occurs in northeastern South America where it is known only from Brazil, Guyana, Suriname, and French Guiana. Spiders of the genus are generally fossorial; however, Ephebopus murinus has a developmental stage that is arboreal. A cladistic analysis of the Theraphosidae retrieves the Aviculariinae as monophyletic, including Avicularia Lamarck, Iridopelma Pocock 1901, Pachistopelma Pocock 1901, Tapinauchenius, Psalmopoeus Pocock, Ephebopus, Stromatopelma Karsch and Heteroscodra Pocock, having as a synapomorphy the well-developed scopulae on tarsi and metatarsi I-II that is very laterally extended.

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In intermittently open estuaries, the sources of organic matter sustaining benthic invertebrates are likely to vary seasonally, particularly between periods of connection and disconnection with the ocean and higher and lower freshwater flows. This study investigated the contribution of allochthonous and autochthonous primary production to the diet of representative invertebrate species using stable isotope analysis (SIA) during the austral summer and winter (2008, 2009) in an intermittently open estuary on the south-eastern coast of Australia. As the study was conducted towards the end of a prolonged period of drought, a reduced influence of freshwater/terrestrial organic matter was expected. Sampling was conducted along an estuarine gradient, including upper, middle and lower reaches and showed that the majority of assimilated organic matter was derived from autochthonous estuarine food sources. Additionally, there was an input of allochthonous organic matter, which varied along the length of the estuary, indicated by distinct longitudinal trends in carbon and nitrogen stable isotope signatures along the estuarine gradient. Marine seaweed contributed to invertebrate diets in the lower reaches of the estuary, while freshwater/terrestrial organic matter had increased influence in the upper reaches. Suspension-feeding invertebrates derived large parts of their diet from freshwater/terrestrial material, despite flows being greatly reduced in comparison with non-drought years.

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A malacofauna límnica exerce importante papel como constituinte da comunidade bentônica e alterações em sua estrutura podem tornar-se prejudiciais para a vida nesses ecossistemas. Com o objetivo de avaliar quali-quantitativamente a malacofauna límnica na área de abrangência da Usina Hidrelétrica de Dona Francisca (UHEDF) (29°26’50’’S e 53°16’50’’W), Agudo, Rio Grande do Sul, Brasil, tomadas as amostras nas fases de pré-enchimento do reservatório em oito estações de coleta em áreas localizadas à montante (E3B, E4B, E5B), à jusante (E1) e na calha central do futuro lago da barragem (E2, E3, E4, E5) e pós-enchimento nas estações E1, E3B e E4B. No período de junho a outubro de 2000 (fase de pré-enchimento) e de junho a outubro de 2001 (fase de pós-enchimento) foram realizadas amostragens mensais, consistindo de três réplicas por estação de coleta (margens-centro), através do uso do amostrador de Surber modificado com área de 60 cm² e 15 cm de altura, delimitando o tamanho amostral. A fauna foi retirada manualmente dos clastos maiores sendo o sedimento de granulometria mais fina, passada através de peneira com malha de 1mm. Em laboratório foi realizada a identificação específica dos moluscos e da fauna acompanhante de macroinvertebrados , quando possível até família. Os organismos foram fixados em álcool 70%. Foram identificadas 10 famílias de Mollusca com quinze espécies. Para Gastropoda foram registradas seis famílias com nove espécies: Ampullariidae – Pomacea canaliculata (Lamarck, 1801); Hydrobiidae – Potamolithus aff. catharinae Pilsbry, 1911, Potamolithus ribeirensis Pilsbry, 1911, Potamolithus sp.1 e Heleobia sp.; Chilinidae – Chilina parva Martens, 1868; Lymnaeidae – Lymnaea columella Say, 1817; Ancylidae – Gundlachia concentrica (Orbigny, 1835); e Physidae – Stenophysa marmorata (Guilding, 1938). Para Bivalvia: Corbiculidae – Corbicula fluminea (Müller, 1774); Mycetopodidae – Anodontites iheringi (Clessin, 1882), Anodontites lucidus (Orbigny, 1835); Hyriidae – Diplodon charruanus (Orbigny, 1835); Sphaeriidae – Pisidium punctiferum (Guppy, 1817) e Pisidium sp. Na fase de pré-enchimento do reservatório, a correlação de Pearson apontou correlação positiva entre a granulometria e a densidade de moluscos (r=0,15) e correlação negativa entre os fatores físico-químicos e a densidade de moluscos bentônicos (r=-0,28). A análise de agrupamento das espécies de moluscos na fase de pré-enchimento evidenciou a formação de dois grupos distintos: o primeiro formado por espécies acidentais, segundo o cálculo da Constância, e o segundo formado por espécies constantes, xviii acessórias e uma acidental (Potamolithus sp.1) que no entanto foi abundante em E1 e E2. O resultado da freqüência relativa em relação à fase de pré-enchimento do reservatório mostrou a família Hydrobiidae, com quatro espécies, com maior abundância e riqueza de espécies, seguida por Chilinidae, representada por C. parva. Ambas as famílias representaram um total de 93,9% em relação à comunidade de moluscos amostrados. Tais resultados refletem o tipo de ambiente da área: leito formado por matacões e calhaus, favoráveis à instalação e manutenção daqueles moluscos. Na fase de pós-enchimento do reservatório foram registrados o aumento na riqueza e diversidade de espécies nas três estações de coleta amostradas (exceto em E3B – com menor diversidade no pós-enchimento) e diminuição significativa nas densidades mensais e totais de moluscos bentônicos. Os testes de aleatorização, entretanto, não revelaram diferenças significativas entre as duas fases e em relação ao funcionamento da UHEDF. Os fatores físico-químicos apontaram correlação positiva com a densidade de moluscos (r=0,19), ressaltando as diferenças significativas nos valores de pH, oxigênio dissolvido, oxigênio saturado nesta fase. Em E1 mais atingida pelo funcionamento da UHEDF, registrou-se uma acentuada diminuição nas densidades mensais e totais de moluscos bentônicos, não obstante, a riqueza e diversidade apresentaram maiores valores nesta fase. As espécies mantiveram-se as mesmas em ambas as fases.

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The niche breadth of the Portunidae and their overlap on the subtidal sediments of Fortaleza bay, Ubatuba (São Paulo) was analyzed. Samples were made monthly from November/1988 to October/1989, inseven areas of the bay using a shrimp fishery boat equipped with two otter-trawls. Each area was characterized based on environmental factors such as depth, temperature, salinity, dissolved oxygen, organic matter and granulometric composition of the sediment. The number of individuais of each species was registered to each area (resource). Levins's standardized measure (BA) and niche percentage were calculated. Five species of swimming crabs were recorded in this study: Callinectes ornatus Ordway, 1863, Arenaeus cribrarius (Lamarck, 1818), Portunus spinimanus Latreille, 1819, Callinectes danae Smith, 1869 and Portunus spinicarpus (Stimpson, 1871). The widest ecological niche occurred to C. ornatus, present in all sampled areas (generalist species). Such fact can be related to high sediment tolerance when it is compared to P. spinimanus (especialist species) which was limited to the areas with coarse granulometric fractions. Highest niche overlap was verified between C. danae and A. cribrarius may be due to greater salinity tolerance of these species. The low occurrence of P. spinicarpus and its reduced niche size in Fortaleza Bay are due to association of this species to cold water currents (ACAS) more evidente in smaler depths during summer months. One future evaluation of the portunid diet can be useful to complement informations about this important aspect of the marine ecology.

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Foram estudadas 40 cultivares de batata-doce Ipomoea batatas (L.) Lamarck, objetivando avaliar a resistência ao ataque da broca Euscepes postfasciatus Fairmaire. Numa primeira fase da pesquisa foi medida a atratividade, a não-preferência para alimentação e oviposição em ramas e raízes. Dos resultados foram escolhidas oito cultivares resistentes e duas suscetíveis. Numa segunda fase utilizaram-se raízes das cultivares escolhidas para estudar a resistência a E. postfasciatus. Ramas e raízes foram oferecidas a adultos da broca em arenas com livre chance de escolha, com seis repetições. As avaliações foram feitas aos 5, 10, 30, 60 min., 3h e 24h após a liberação. O melhor tamanho de rama, entre os testados, a ser utilizado foi o de 35 cm. Os adultos da broca ao serem liberados nas arenas, dirigiram-se rapidamente para o material e atacaram as mais atrativas, prioritariamente nos ramos mais grossos ou na inserção das folhas. As cultivares com ramas menos atrativas foram: Rocha da Paz, Mineira, Lagartixa e Bom Nome, sendo que os tubérculos das cultivares Lagartixa e Bom Nome também foram menos danificados e juntamente com Caboatã, não preferidas para oviposição. As raízes e ramas das cultivares Granfina e UFRPE foram as mais atrativas e as mais danificadas portanto devem ser evitadas, enquanto que as cultivares Lagartixa e Bom Nome devem ser recomendadas pelo seu melhore desempenho.

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Timeplace learning is the capacity of organisms to associate both space and time with a biological relevant stimulus such as food. Experiments are usually done with food restricted animals due to the belief that food system activation is necessary for timeplace learning. Another line of thought suggest that, in addition to food system activation, response cost should be increased to effectively allow timeplace discrimination. The purpose of this experiment was to test whether a complex environment, which presumably implied in a heightened response cost, would facilitate timeplace association in satiated rats using a highly palatable food as reward. Nine rats were trained in a timeplace task for 30 nonconsecutive days. A large experimental box (1x1m) divided in four compartments was used. To access each compartment the animal had to overcome a series of obstacles such as ramps, staircases and mazes. Two feeders localized in opposite compartments were rewarded with sunflower seeds in two daily sessions. One feeder offered the reward during the morning sessions while the second feeder in afternoon sessions. After the 15th day of training, the animals began to show a preference for the correct feeder during the correct time of day expressed by increased frequency of visits as well as lower latency to access the feeders. These results suggest that satiated animals are also capable of learning a timespace task as far as the experimental context is complex enough to result in a higher response cost