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Ninety-six bigeye tuna (88– 134 cm fork length) were caught and released with implanted archival (electronic data storage) tags near fish-aggregating devices (FADs) in the equatorial eastern Pacific Ocean (EPO) during April 2000. Twenty-nine fish were recaptured, and the data from twenty-seven tags were successfully downloaded and processed. Time at liberty ranged from 8 to 446 days, and data for 23 fish at liberty for 30 days or more are presented. The accuracy in geolocation estimates, derived from the light level data, is about 2 degrees in latitude and 0.5 degrees in longitude in this region. The movement paths derived from the filtered geolocation estimates indicated that none of the fish traveled west of 110°W during the period between release and recapture. The null hypothesis that the movement path is random was rejected in 17 of the 22 statistical tests of the observed movement paths. The estimated mean velocity was 117 km/d. The fish exhibited occasional deep-diving behavior, and some dives exceeded 1000 m where temperatures were less than 3°C. Evaluations of timed depth records, resulted in the discrimination of three distinct behaviors: 54.3% of all days were classified as unassociated (with a floating object) type-1 behavior, 27.7% as unassociated type-2 behavior, and 18.7% as behavior associated with a floating object. The mean residence time at floating objects was 3.1 d. Data sets separated into day and night were used to evaluate diel differences in behavior and habitat selection. When the fish were exhibiting unassociated type-1 behavior (diel vertical migrations), they were mostly at depths of less than 50 m (within the mixed layer) throughout the night, and during the day between 200 and 300 m and 13° and 14°C. They shifted their average depths in conjunction with dawn and dusk events, presumably tracking the deep-scattering layer as a foraging strategy. There were also observed changes in the average nighttime depth distributions of the fish in relation to moon phase.

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麻疯树(Jatropha curcas L.)属大戟科麻疯树属多年生亚乔木,耐干旱、高温和贫瘠等,具很强的抗逆性,在干热河谷等边际土地上生长良好。其种子富含油脂,是制备生物柴油的理想材料,为重要的能源植物之一。油体(oil body)是种子细胞中重要的细胞器, 脂肪酸以三脂酰甘油(triacylglyeerols,TAG)的形式储存其内,是种子萌发和幼苗生长时所需碳骨架和能量的主要来源。种子萌发为生命萌动并构建成自养个体的过程,是高等植物生长发育中的重要事件。 本论文运用高通量的蛋白质组学研究手段,结合电镜技术和生理学分析,对麻疯树种子油体以及种子萌发过程中蛋白质表达、生理学响应和细胞结构变化进行了研究。 从麻疯树种子胚乳中分离油体,再从油体中提取蛋白,经双向凝胶电泳后,得到油体蛋白质组的二维表达谱,这些蛋白质主要分布在等电点5 ~ 10、分子量12 ~ 66 kDa的范围内;图像分析表明,油体蛋白质组至少有141个蛋白点,其中酸性蛋白74个,碱性蛋白67个,表达丰度较高的多为低分子量碱性蛋白。对其中36个重要蛋白点进行LC-MS/MS质谱分析,得到鉴定的蛋白分别为30个基因的表达产物,主要包括油体重要的结构蛋白油质蛋白(oleosin)和caleosin,麻疯树种子毒蛋白curcin,以及新鉴定得到的另一种可能的麻疯树种子毒蛋白,人体过敏反应蛋白橡胶延伸因子(REF)。还有四个与脂肪酸代谢相关的酶,其中3-羟酰-酰基载体蛋白(ACP)脱水/催化酶和醇酰基转移酶与脂肪酸合成有关,而脂氧合酶和磷脂酶D在脂肪酸降解中发挥作用,显示部分脂肪酸代谢相关的酶在油体储存状态就已附着在油体上,为种子萌发时动员油脂做好了准备。 麻疯树种子胚乳发达,在32℃湿润土壤中很快就会萌动,胚轴伸长露出胚根,长出新根,约4天后形成出土子叶幼苗。种子萌发过程中胚乳主要成分含量测定表明,含水量在前24小时迅速上升,至48小时增加缓慢,此后开始较快上升,可分为三个阶段,呈现“S”型的变化;粗脂肪和粗蛋白在前两个阶段变化不大,进入第三阶段后其含量迅速下降,前者先于后者,分别在萌发后72小时和96小时后开始明显减少,说明被大量降解、转化,供萌发生长利用,其中主要组分亚油酸最为明显。细胞超微结构观察发现,排列整齐充满整个胚乳细胞的油体和嵌合在油体中的蛋白储存泡在种子萌发过程中,随着线粒体、乙醛酸循环体和液泡的出现增多或增大而被逐渐解体、减少或消失;同时,发现脂肪酸主要在乙醛酸循环体、蛋白颗粒主要在液泡中被降解或转化。 蛋白质组学分析表明,麻疯树种子在萌发72小时过程中变化量在两倍以上的差异蛋白点共有141个,所有的差异蛋白均通过LC-MS/MS分析和NCBI蛋白数据库搜索得到鉴定。其中包括多个参与降解储藏油脂的酶,如乙醛酸循环途径中的顺乌头酸酶,异柠檬酸裂解酶和苹果酸脱氢酶等,均从种子萌发48小时开始表达量明显上升;葡糖异生途径中的酶在种子萌发中的积累略晚于乙醛酸循环途径,如烯醇酶,磷酸甘油酸变位酶,磷酸甘油酸激酶,磷酸丙糖异构酶和醛缩酶大多在萌发约60小时后表达量开始上调。分析结果表明,乙醛酸循环途径在种子萌发48小时后被激活,与电镜观察胚乳细胞发现油脂在萌发48小时时开始被动员相一致,因而大规模的油脂动员开始于种子萌发的第三阶段。 同时,蛋白质组学的分析结果也得到了种子胚乳组分变化分析及电镜观察结果的印证。超微细胞结构观察显示种子储藏蛋白降解在萌发第二阶段启动,主要在液泡中进行降解。粗脂肪的含量在72小时时显著降低,而电镜观察显示此时胚乳细胞中出现中央大液泡,出现大量的线粒体和乙醛酸循环体,细胞结构发生重大变化,萌发96小时后仅有少量油体残留于胚乳细胞中,这些都为储藏油脂在麻疯树种子萌发过程中的降解方式提供了重要证据。许多其他的功能蛋白在种子萌发过程中也发生了变化,表明种子萌发过程中不仅发生储藏物质的动员,也发生抗逆反应以及植物形态的构建等众多其他生理生化反应。 本研究首次对麻疯树种子油体进行了蛋白组成分析,并结合电镜技术及生理分析深入探讨了种子储藏物质在萌发中的降解方式,为更好的理解油体结构、木本油料种子的萌发机制和对麻疯树进行品种的改良提供了参考。

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Hydrogenated tetrahedral amorphous carbon (ta-C:H) is a form of diamond-like carbon with a high sp3 content (>60%), grown here using a plasma beam source. Information on the behaviour of hydrogen upon annealing is obtained from effusion measurements, which show that hydrogen does not effuse significantly at temperatures less than 500 °C in films grown using methane and 700 °C in films grown using acetylene. Raman measurements show no significant structural changes at temperatures up to 300 °C. At higher temperatures, corresponding to the onset of effusion, the Raman spectra show a clustering of the sp2 phase. The density of states of ta-C:H is directly measured using scanning tunnelling spectroscopy. The measured gradients of the conduction and valence band tails increase up to 300 °C, confirming the occurrence of band tail sharpening. Examination of the photoluminescence background in the Raman spectra shows an increase in photoluminescence intensity with decreasing defect density, providing evidence that paramagnetic defects are the dominant non-radiative recombination centres in ta-C:H.

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Three-phase induction motors offer significant advantages over commutator motors in some domestic appliances. Models for wide speed range three-phase induction motors for use in a horizontal axis washing machine have been developed using the MEGA finite element package with an external formulation for calculating iron losses. Motor loss predictions have been verified using a novel high accuracy calorimeter. Good agreement has been observed over a wide speed range at different loadings. The model is used to predict motor temperature rise under typical washing machine loading conditions to ensure its limiting temperature is not exceeded and enables alternative designs to be investigated without recourse to physical prototypes. © 2005 IEEE.

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A blood coagulation factor IX-binding protein (TSV-FIX-BP) was isolated from the snake venom of Trimeresurus stejnegeri. On SDS-polyacrylamide gel electrophoresis, TSV-FIX-BP showed a single band with an apparent molecular weight of 23,000 under non-reducing conditions. and two distinct bands with apparent molecular weights of 14,800 and 14,000 under reducing conditions. cDNA clones containing the coding sequences of TSV-FIX-BP were isolated and sequenced to determine the structure of the precusors of TSV-FIX-BP subunits. The deduced amino acid sequences of two subunits of TSV-FIX-BP were confirmed by N-terminal protein sequencing and trypsin-digested peptide mass fingerprinting. TSV-FIX-BP was a nonenzymatic C-type lectin-like anti-coagulant. The anti-coagulant activity of TSV-FIX-BP was mainly caused by its dose dependent interaction with blood coagulation factor IX but not with blood coagulation factor X. (C) 2003 Elsevier Science Ltd. All rights reserved.

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The ability to feed on vertebrate blood has evolved many times in various arthropod clades. Consequently, saliva of blood-feeding arthropods has proven to be a rich source of antihemostatic molecules. A variety of platelet aggregation inhibitors antagonize platelet responses to wound-generated signals, including ADP, thrombin, and collagen. Anticoagulants disrupt elements of both the intrinsic and extrinsic pathways. Vasodilators include nitrophorins (nitric oxide storage and transport heme proteins), a variety of peptides that mimic endogenous vasodilatory neuropeptides, and proteins that catabolize or sequester endogenous vasoconstrictors. Multiple salivary proteins may be directed against each component of hemostasis, resulting in both redundancy and in some cases cooperative interactions between antihemostatic proteins. The complexity and redundancy of saliva ensures an efficient blood meal for the arthropod, but it also provides a diverse array of novel antihemostatic molecules for the pharmacologist.

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This letter presents a novel lateral superjunction lateral insulated-gate bipolar transistor (LIGBT) in partial silicon-on-insulator (SOI) technology in 0.18-μm partial-SOI (PSOI) high-voltage (HV) process. For an n-type superjunction LIGBT, the p-layer in the superjunction drift region not only helps in achieving uniform electric field distribution but also contributes to the on-state current. The superjunction LIGBT successfully achieves a breakdown voltage (BV) of 210 V with an R dson of 765 mΩ ̇ mm 2. It exhibits half the value of specific on-state resistance R dson and three times higher saturation current (I dsat) for the same BV, compared to a comparable lateral superjunction laterally diffused metal-oxide-semiconductor fabricated in the same technology. It also performs well in higher temperature dc operation with 38.8% increase in R dson at 175°C, compared to the room temperature without any degradation in latch-up performance. To realize this device, it only requires one additional mask layer into X-FAB 0.18-μm PSOI HV process. © 2012 IEEE.

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Engineering changes (ECs) are essential in complex product development, and their management is a crucial discipline for engineering industries. Numerous methods have been developed to support EC management (ECM), of which the change prediction method (CPM) is one of the most established. This article contributes a requirements-based benchmarking approach to assess and improve existing methods. The CPM is selected to be improved. First, based on a comprehensive literature survey and insights from industrial case studies, a set of 25 requirements for change management methods are developed. Second, these requirements are used as benchmarking criteria to assess the CPM in comparison to seven other promising methods. Third, the best-in-class solutions for each requirement are investigated to draw improvement suggestions for the CPM. Finally, an enhanced ECM method which implements these improvements is presented. © 2013 © 2013 The Author(s). Published by Taylor & Francis.