959 resultados para Aisberg-2-2006-1
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Resources created at the University of Southampton for the module Remote Sensing for Earth Observation
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Animal science newsletter about Johne's Disease in cattle. Statistics, treatments, information about the disease itself and more.
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In this work, biodiesel was produced from castor oil that was a byproduct glycerin. The molar ratio between oil and alcohol, as well as the use of (KOH) catalyst to provide the chemical reaction is based on literature. The best results were obtained using 1 mol of castor oil (260g) to 3 moles of methyl alcohol (138g), using 1.0% KOH as catalyst at a temperature of 260 ° C and shaken at 120 rpm. The oil used was commercially available, the process involves the reaction of transesterification of a vegetable oil with methyl alcohol. The product of this reaction is an ester, biodiesel being the main product and the glycerin by-product which has undergone treatment for use as raw material for the production of allyl alcohol. The great advantage of the use of glycerin to obtain allyl alcohol is that its use eliminates the large amount of waste of the biodiesel and various forms of insult to the environment. The reactions for the formation of allyl alcohol was conducted from formic acid and glycerin in a ratio 1/1, at a temperature of 260oC in a heater blanket, being sprayed by a spiral condenser for a period of 2 hours and the product obtained contains mostly the allylic alcohol .. The monitoring of reactions was performed by UV-Visible Spectrophotometer: FTIR Fourier transform, the analysis showed that these changes occur spectrometer indicating the formation of the product allylic alcohol (prop-2-en-1-ol) in the presence of water, This alcohol was appointed Alcohol GL. The absorption bands confirms that the reaction was observed in (υ C = C) 1470 -1600 cm -1 and (υ CO), 3610-3670 attributed to C = C groups and OH respectively. The thermal analysis was carried out in a thermogravimetric analyzer SDT Q600, where the mass and temperature are displayed against time, that allows checking the approximate rate of heating. The innovative methodology developed in the laboratory (LABTAM, UFRN), was able to treat the glycerine produced by transesterification of castor oil and used as raw material for production of allyl alcohol, with a yield of 80%, of alcohol, the same is of great importance in the manufacture of polymers, pharmaceuticals, organic compounds, herbicides, pesticides and other chemicals
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This is the Official Roster of the South Carolina soldiers, sailors and marines who served in the World War and contains the names and records, briefly compiled, of the men and women from this state who responded to the call of the President when the United States entered the great conflict. This record gives in as compact form as practicable the following : name; serial number; residence; branch of service; date and place of entry into service; place of birth and age; organizations served in, with dates of assignments and transfers; grades with dates of appointment; engagements, if any; wound received in action, with degree and date; if killed in action or died while in service; person notified, relationship and address; oversea service; date of discharge; citations.
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This publication is volume 2, issue 1 of the University of South Carolina Publications. Series III. Biology. on taxonomic studies of the flora and fauna of South Carolina.
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A bimonthly literary magazine edited by Zhou Shoujuan 周瘦鵑, featuring fiction, topical articles, and entertainment features, published from September 1921 through November 1925.
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SPECT-1 y -2 y SIAP-1 y -2 son proteínas pertenecientes al esporozoíto de Plasmodium falciparum causante de la malaria más agresiva en los humanos. Estas proteínas están involucradas en el paso del parásito a través de las células del hospedero humano y en la invasión del hepatocito, haciéndolas blancos atractivos para ser estudiadas. Péptidos conservados de alta capacidad de unión (cHABPs) a células HeLa y HepG2 derivados de estas moléculas son no inmunogénicos porque son incapaces de generar una respuesta inmunitaria, pero son claves para el parásito porque cumplen una función importante durante la infección del hospedero humano. En este trabajo se encontró que algunos cHABPs pertenecientes a las proteínas SPECT-1 y -2, están posiblemente involucrados con la unión y formación de poros sobre la membrana de las células hospederas, ayudando al esporozoíto a abrirse paso través de las células del hospedero. Por otro lado, con el fin de cambiar el comportamiento inmunológico de cHABPs derivados de SPECT-1 y -2 y SIAP-1 y -2, se obtuvieron nuevos péptidos mediante el reemplazo de aminoácidos críticos por otros residuos cuya masa molecular sea similar, pero diferente en su polaridad. En este trabajo se reporta que dichas modificaciones promovieron cambios en la estructura secundaria (determinada por DC o 1H-RMN) de los péptidos modificados (mHABPs) cuando se comparó con la estructura de los cHABPs nativos; adicionalmente, estos mHABPs invirtieron su comportamiento inmunológico convirtiéndose en péptidos inmunogénicos inductores de anticuerpos. Lo que permite establecer la existencia de una relación entre la estructura que adoptan estos mHABPs con su actividad inmunológica. Además, algunos de los mHABPs estudiados aquí, pueden ser candidatos a ser incluidos en la vacuna contra la malaria químicamente sintetizada multi-epitope y multi-estadio que se está desarrollando en la Fundación Instituto de Inmunología de Colombia (FIDIC).
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Glacier inventories provide the basis for further studies on mass balance and volume change, relevant for local hydrological issues as well as for global calculation of sea level rise. In this study, a new Austrian glacier inventory has been compiled, updating data from 1969 (GI 1) and 1998 (GI 2) based on high-resolution lidar digital elevation models (DEMs) and orthophotos dating from 2004 to 2012 (GI 3). To expand the time series of digital glacier inventories in the past, the glacier outlines of the Little Ice Age maximum state (LIA) have been digitalized based on the lidar DEM and orthophotos. The resulting glacier area for GI 3 of 415.11 ± 11.18 km**2 is 44% of the LIA area. The annual relative area losses are 0.3%/yr for the ~119-year period GI LIA to GI 1 with one period with major glacier advances in the 1920s. From GI 1 to GI 2 (29 years, one advance period of variable length in the 1980s) glacier area decreased by 0.6% yr?1 and from GI 2 to GI 3 (10 years, no advance period) by 1.2%/yr. Regional variability of the annual relative area loss is highest in the latest period, ranging from 0.3 to 6.19%/yr. The mean glacier size decreased from 0.69 km**2 (GI 1) to 0.46 km**2 (GI 3), with 47% of the glaciers being smaller than 0.1 km**2 in GI 3 (22%).
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合成了2种新型的可溶性四氮杂卟啉中间体:反式-1,2二氰-(4-乙基苯)乙烯和顺式-1,2-二氰(4-乙基苯)乙烯。通过UV-Vis,FFIR,GC/MS,^1H NMR等方法对这2种化合物的结构进行了表征,给出了它们完整的结构信息。分析比较了顺、反异构体结构上的差异,分析两者的紫外-可见光谱(UV-Vis)、红外光谱(FTIR)和核磁共振光谱(^1H NMR)谱图的差异及其产生原因。
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一、大鼠海马-前额叶回路在学习记忆中的作用 解剖学研究证实大鼠和猴的海马结构(hippocampal formation, HF;本文‘海马 (hippocampus, Hip)’一词即指海马结构)和前额叶 (prefrontal cortex, PFC) 之间存在一条单向、同侧和单突触的神经回路,即海马-前额叶回路(Hip-PFC回路)。Hip和PFC均参与学习记忆等多种认知功能,PFC是工作记忆的关键脑区,而Hip是空间参考记忆的关键脑区。虽然人们已经对PFC和Hip进行了广泛深入的研究,但对Hip-PFC回路参与哪些认知功能还知之甚少。本研究的目的就是通过暂时阻断Hip-PFC回路,探讨其在学习和记忆中的作用。 在大鼠,Hip-PFC回路中的纤维主要从Hip腹部 (ventral hippocampus, VH)发出,投射到PFC的前边缘皮质(prelimbic cortex, PLC)、下边缘皮质 (infralimbic cortex, ILC) 和外侧前额叶 (lateral prefrontal cortex) 等亚区,其中PLC是Hip-PFC主要投射的区域。我们通过给动物安装慢性导管向脑内注射GABAA受体激动剂muscimol (MU) 阻断Hip-PFC回路。注射位点包括 ①双侧PLC,②双侧VH,③一侧VH和对侧PLC (VH-PLC)。我们首先观察了在PLC或VH局部注射MU对自由活动大鼠PLC和VH脑电功率的影响,并以此确定在行为实验中所用蝇蕈醇的剂量。然后采用T-迷宫空间交互延缓作业 (spatial delayed alternation task) 测试Hip-PFC回路被阻断的动物的空间工作记忆功能;采用被动回避作业 (passive avoidance task) 测试其情绪相关记忆的能力(训练前给药;24 h后重测试);采用Morris水迷宫作业 (Morris water maze task) 测试其空间参考记忆的能力(每天训练前给药;训练期(3 d)结束24 h后重测试)。结果表明:在大鼠PLC或VH局部注射0.5 μg/0.25μl MU后30 min显著抑制VH 和PLC的脑电功率 (VH, p < 0.01; PLC, p < 0.05 vs. PBS/baseline)。注射MU (0.5 μg/0.25μl) 到 ①双侧PLC、②双侧VH、③VH-PLC均显著降低动物在空间交互延缓作业 (All p < 0.001, vs. PBS) 和空间Morris水迷宫作业中的成绩 (All p < 0.05, vs. PBS),表明Hip-PFC回路在空间工作记忆(空间短时记忆)和在空间参考记忆(空间长时记忆)中均起重要作用。在空间交互延缓作业中,双侧PLC被抑制的大鼠的成绩显著低于双侧VH或VH-PLC被抑制的动物,说明PFC在空间工作记忆功能中占有主导地位。在被动回避作业中,双侧VH被抑制动物的回避反应的潜伏期显著短于对照动物 (p < 0.05 vs. PBS),说明双侧VH被抑制动物的情绪记忆受损;而双侧PLC或VH-PLC被抑制的动物其回避反应的潜伏期与对照动物无显著差异 (PLC, p > 0.9; VH-PLC, p > 0.3 vs. PBS),表明双侧PLC或VH-PLC被抑制的动物情绪记忆正常。被动回避作业的结果说明VH参与情绪记忆的形成,但Hip-PFC回路在情绪记忆形成中不起重要作用。 以上结果表明,大鼠Hip-PFC回路参与空间工作记忆和空间参考记忆而不是情绪记忆功能。情绪记忆的关键脑结构是杏仁复合体 (amygdala complex, AMC),VH与AMC有密切的纤维联系。VH被抑制的大鼠情绪记忆受损,说明情绪记忆可能与AMC-Hip回路有关。情绪记忆与空间记忆(参考记忆和工作记忆)在解剖上的分离说明,对于不同类型的记忆来说,其在脑内的信息加工过程是并行的。神经回路内部的信息加工过程则是串行的,回路上任何一个结构的破坏均可导致回路功能的损伤。本研究的结果为学习记忆的“多重记忆系统”理论和记忆信息加工的串行并行机制提供了新的实验证据。 二、芬克罗酮改善成年恒河猴空间工作记忆的谷氨酸机制 芬克罗酮是中科院昆明植物所郝小江等合成的取代吡咯烷酮类化合物。中科院昆明动物所蔡景霞等发现芬克罗酮能改善东莨菪碱、育亨宾等导致的多种动物的不同类型的学习记忆障碍,提高老年动物的学习记忆能力,尤其是老年猴的空间工作记忆。已证实芬克罗酮为部分钙激动剂,可使脑缺血沙土鼠脑内升高的谷氨酸降低,而使正常的沙土鼠海马胞外谷氨酸释放增加。那么芬克罗酮能否提高正常动物的学习记忆,其对正常动物学习记忆的提高是否与其增加谷氨酸的释放有关?本研究采用空间延缓反应作业和谷氨酸NMDA受体拮抗剂MK-801在正常成年猴恒河猴上探讨了以上问题。 结果表明,口服芬克罗酮可显著提高成年猴的空间工作记忆,其量效曲线呈倒‘U’形,符合许多促智药的量效特点。0.25 mg/kg和0.5 mg/kg为芬克罗酮的最佳有效剂量 (p < 0.05 vs. 安慰剂)。肌注MK-801 (0.1 mg/kg) 显著降低成年猴的空间工作记忆 (p < 0.01 vs. 安慰剂),而口服2.0 mg/kg和4.0 mg/kg的芬克罗酮则显著改善MK-801导致的工作记忆障碍 (p < 0.05 vs. MK-801)。芬克罗酮的所有测试剂量不影响猴在作业中的反应时 (p > 0.05 vs. 安慰剂),表明芬克罗酮在该剂量范围不影响动物的运动能力。 本研究结果提示,芬克罗酮可能通钙激动作用促进谷氨酸的释放,在一定剂量范围内提高胞外谷氨酸水平,提高正常动物的空间工作记忆等认知功能。 关键词:芬克罗酮,恒河猴,空间工作记忆,空间延缓反应作业,谷氨酸,MK-801