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Gulf of Mexico, white shrimp, Litopenaeus setiferus, catch statistics have been collected by NOAA’s National Marine Fisheries Service for over 50 years. Recent occurrences such as natural and manmade disasters have raised awareness for the need to publish these types of data. Here we report shrimp data collected from 1984 to 2011. These 28 years of catch history are the time series used in the most recent Gulf of Mexico white shrimp stock assessment. Fishing effort for this stock has fluctuated over the period reported, ranging from 54,675 to 162,952 days fished. Catch averaged 55.7 million pounds per year, increasing significantly over the times series. In addition, catch rates have been increasing in recent years, with CPUE levels ranging from 315 lb/day fished in 2002, to 1,175 lb/ day fished in 2008. The high CPUE’s we have measured is one indication that the stock was not in decline during this time period. Consequently, we believe the decline in effort levels is due purely to economic factors. Current stock assessments are now using these baseline data to provide managers with further insights into the Gulf L. setiferus stocks.

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采用PEG/DMSO融合法,从普通烟草(Nicotiana tabacum L.cv.Xanthi nc)叶肉和毛曼陀罗(Datura innoxia Mill.)茎或叶愈伤组织原生质体融合获得I5株花盆中健康生长的族间体细胞杂种植株;其中11株是在没有选择压力的条件下获得,4株则是在有IOA和R6G选择系统存在下获得。同时获得一株试管开花且形态异常的植株和一株花盆中生长的嵌合植株。lOmM IOA和I5μ g/ml R6G均能分别有效地抑制烟草叶肉和毛曼陀罗愈伤组织原生质体的分裂;10% DMSO能显著提高原生质体融合率;PEG种类并不重要,但浓度则很重要;BAP较ZT,KT对植株分化有更好的诱导效果。杂种的形态、细胞、同工酶、Southern杂交,花粉育性分析结果如下:1、l5株杂种较双亲普遍株型矮小,生长缓慢,形态接近烟草但不很正常,根据形态特征可分为两种类型:(1)共有8株,其叶片大小、形状、颜色、开花习惯、花类型(单花)等均与毛曼陀罗接近,但子房败育;(2)共有7株,其株型、叶片形状、颜色、光滑度、花形状、类型(圆锥状花序)、颜色更接近烟草,但少数杂种开单花或先单花后圆锥状花序或先单花后两种花并存,且开花时间不一,部分子房败育。2、杂种染色体数目大都在60~90之间,个别者较少(48条)或较多(125条),没有一株为双二倍体(2n=96),并全部为混倍体。3、15株杂种植株均有双亲的细胞色素氧化酶同工酶特征谱带;大部分都有双亲的过氧化物酶同工酶特征谱带,少都仅具烟草的谱带。4、Hae Ⅲ/水稻rDNA的Southern杂交分析表明杂种1较双亲多一条谱带,杂种2较双亲也多一条弱带,其它杂种尚待定。5、花粉活力测定表明毛曼陀罗(种子再生而来)的为99%,烟草(原生质体再生而来)为80~90%,而杂种的为24~61%,育性普遍低于双亲。

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In March 2006, a dead, male bottlenose dolphin (Tursiops truncatus) was found in the salt marsh in Charleston, South Carolina, United States. During necropsy, an enterolith was found completely obstructing the intestinal lumen. Further examination of the enterolith revealed a stingray spine nidus. Most terrestrial enteroliths are composed primarily of struvite (magnesium ammonium phosphate); however, the majority of the enterolith discovered in the stranded dolphin was composed of calcium phosphate carbonate. This case provides an interesting comparison of the variation in the mineral composition between terrestrial and marine enteroliths.

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The bastard grunt (Pomadasys incisus) is one of the most abundant coastal demersal fishes inhabiting the Canary Islands. Age and growth were studied from samples collected between October 2000 and September 2001. Growth analysis revealed that this species is a fast growing and moderately short-lived species (ages up to seven years recorded). Length-at-age was described by the von Bertalanffy growth model (L∞=309.58 mm; k=0.220/year; t0=–1.865 year), the Schnute growth model (y1=126.66 mm; y2=293.50 mm; a=–0.426; b= 5.963), and the seasonalized von Bertalanffy growth model (L∞=309.93 mm; k=0.218/ year; t0= –1.896 year; C=0.555; ts=0.652). Individuals grow quickly in their first year, attaining approximately 60% of their maximum length; after the first year, their growth rate drops rapidly as energy is probably diverted to reproduction. The parameters of the von Bertalanffy weight growth curve were W∞=788.22 mm; k=0.1567/year; t0= –1.984 year. Fish total length and otolith radius were closely correlated, r2=0.912. A power relationship was estimated between the total length and the otolith radius (a=49.93; ν=0.851). A year’s growth was represented by an opaque and hyaline (translucent) zone—an annulus. Backcalculated lengths were similar to those predicted by the growth models. Growth parameters estimated from the backcalculated sizes at age were L∞=315.23 mm; k=0.217/year; and t0= –1.73 year.

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毛乌素沙地是中国半干旱地区典型沙地,这里的干旱生态系统对全球的水热配合格局的变化具有很灵敏的响应。随着未来全球气候变化,如温度和降水量变化,将给这里的陆地生态系统分布格局和生产力以及水分平衡带来巨大影响。故本文人工控制157. 5mm、315. Omm、472. 5mm和630. Omm4种施水量水平以及25/20℃和28/23℃(白天/晚上)两种温度,来研究与模拟毛乌素沙地优势植物对水分和温度变化的响应。 以沙柳、杨柴和油蒿幼苗为研究对象,人工控制4种降水量水平来探讨它们的水分平衡对全球变化中降水量变化的响应。结果表明,随着施水量的增加,沙地贮水量及其它的变化量、湿度、蒸发量和蒸腾量均逐渐增大。并且157. 5mm和315. Omm施水量的植物沙地出现水分亏缺现象。相同施水量下,沙地蓄水量和湿度均杨柴沙地>沙柳沙地>油蒿沙地,而植物蒸腾量却油蒿>沙柳>杨柴。 以沙柳和油蒿幼苗为研究对象,人工控制4种降水量水平来探讨植物气体交换过程对全球变化中降水量变化的响应。结果表明,施水量的增加显著提高了两种植物的净光合速率、蒸腾速率、气孔导度和光能利用效率,并且显著降低了叶片温度。同时,157. 5mm施水量造成沙柳和油蒿的净光合速率和蒸腾速率具有显著的“午睡”现象,而充足施水却有效的解除或缓解这种“午睡”现象。 以沙柳、杨柴、油蒿和柠条幼苗为研究对象,人工控制4种降水量水平来探讨植物叶绿素荧光对全球变化中降水量变化的响应。结果表明,不同施水量对这4种植物的初始荧光、最大荧光、可变荧光和PSII光化学效率均具有显著影响。157. 5mm施水量的沙柳、杨柴、油蒿和柠条以及630. Omm施水量的柠条出现明显的光抑制现象。 以沙柳、杨柴、油蒿和柠条幼苗为研究对象,人工控制4种降水量水平来探讨植物生长对全球变化中降水量变化的响应。结果表明,施水量的增加对沙柳、油蒿和杨柴枝叶形态和生物量等都具有显著正效应。而157. 5mm和630. Omrn的施水量对柠条生长具有负作用。另外,沙柳、杨柴和油蒿根冠生物量比随着施水量增加均逐渐减小,而不同施水量的油蒿根冠生物量比之间差异不显著。 以柠条、杨柴和油蒿幼苗为研究对象,人工控制两种温度水平来探讨植物形态、生物量和气候交换特征对增温的响应。结果表明,增温显著提高了柠条和杨柴株高、叶数、叶面积、生物量、净光合速率、蒸腾速率和气孔导度,却显著降低了水分利用效率。增温对油蒿叶数、叶大小、叶面积、生物量、蒸腾速率和气孔导度没有显著影响,却显著提高了油蒿的树高和净光合速率。柠条、杨柴和油蒿之间的种间生长和生理特征均有显著差异。

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Absolute fecundity of Schizothorax plagiostomus varied from 3474 in a fish measuring 345 mm (T.L.) and weighing 315 g to 13916 in a fish measuring 540 mm (T.L.) and weighing 1370 g. The weight of the fish ovaries accounted for 7.02 to 17.78% of the total weight of the fish. The average number of eggs per kg weight of fish and per gram of ovary weight was found to be 10820 and 81 respectively. The fecundity per kg of body weight was found to be 11539. The relationships between fecundity and other parameters (fish length/fish weight/ovary weight/ovary volume/ovary length) and fish length-ovary weight and fish weight-ovary weight were also determined.

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利用RNAi改良大豆油脂品质 大豆[Glycine max (L.) Merr.]起源于中国,栽培历史悠久,是重要的粮食作物, 同时也是植物油和蛋白的重要来源。随着经济的发展和生活水平的提高,人们不但对大豆的需求量大大增加,同时对大豆的品质也提出了更高的要求。近年来,我国大豆进口量逐年攀升,已远远超过本国生产量。国外转抗除草剂转基因大豆大面积种植大大降低了生产成本,直接影响了我国大豆生产。因此,提高产量和改良品质是当前中国大豆生产所面临的重要课题。基因工程是大豆品种改良更为有效和快速的方法,但是由于历史原因我国的大豆转基因育种与发达国家尚存在一定差距,对我国的大豆生产贡献十分有限。因此,建立高效的大豆转化体系,加强大豆基因工程研究和育种是解决大豆面临困境的关键。 本研究的目的是以我国主要栽培大豆品种(黑农、合丰和东农等)为材料,利用GUS(β-glucuronidase)报告基因和RNAi技术,建立高效的大豆基因转化体系和基因功能研究体系。为大豆产量和品质基因工程改良提供技术手段和理论基础。结果如下: 以大豆下胚轴为外植体,对分生组织产生不定芽的频率进行了研究。培养基中添加高浓度BAP(6-benzylaminopurine)可以诱导外植体分生组织增殖产生不定芽的发生率;在培养基中添加银离子可以明显地促进大豆单个外植体多芽的产生,使得诱导不定芽总数目显著增加;不同基因型大豆再生不定芽能力有着较大区别,黑农44,黑农37,合丰35,合丰39等品种再生能力强;相对于大豆子叶节等再生系统,大豆下胚轴体系具有高效高频的再生特点(总的再生频率高于80%),且重复性好,容易操作。 以大豆下胚轴为外植体,用含有GUS报告基因的根癌农杆菌对其进行遗传转化,并重点对农杆菌菌液浓度、农杆菌侵染时间、乙酰丁香酮(AS)和抗氧化剂浓度等因素对农杆菌大豆转化效率的影响进行了研究。组织化学染色结果显示GUS基因在外植体顶端表达强烈,表达位置主要位于初生芽基部周围的分生组织。 农杆菌浸染时间以 4h 为最佳,此时的GUS瞬时表达频率可达73.0%;培养基中添加浓度为200μmol/L的乙酰丁香酮,可以显著增加GUS瞬时表达频率。抗氧化剂可以显著降低共培养阶段外植体的褐化和坏死率,进而显著提高农杆菌转化效率。用根癌农杆菌转化大豆下胚轴的方法得到了表达GUS基因转基因大豆株系。 利用大豆油酸去饱和酶基因(FAD2-1;Genbank, L43920)在第315-852碱基之间的基因片断构建了反向重复的RNAi表达载体,以农杆菌介导大豆下胚轴转化方法进行转化,并且获得转基因植株。经过PCR,Southern杂交和转基因后代的脂肪酸分析,表明沉默结构已经成功整合到大豆基因组中,并成功抑制了内源基因的表达。与栽培大豆品种相比较,转基因大豆种子的脂肪酸组成发生显著变化,油酸含量由栽培大豆的18.1%增加到71.5%¬-81.9%;亚油酸含量从栽培大豆的46.4%降到了约3.4%。 栽培大豆种子中油酸去饱和比率(ODP, oleic desaturation proportion)为0.76 到 0.84,转基因大豆种子的油酸去饱和比率降为0.06-0.26,表明Δ12-去饱和酶活性降低了74%-94%。上述结果表明,我们构建的RNAi反向重复序列沉默结构高效地抑制了大豆种子FAD2-1基因。 在本研究中,我们通过外源GUS基因的表达和内源FAD2基因的抑制,成功地建立了以大豆下胚轴为外植体的高效农杆菌介导大豆转化体系,并获得了相应的转基因株系。本研究对我国大豆品种基因工程改良以及进一步大豆功能基因组研究有重要参考价值。 四合木茎积累三脂酰甘油特征 四合木(Tetraena mongotica Maxim)是蒺藜科(Zygophyllaceac)四合木属唯一的种,是地球上最具代表性的古老残遗濒危珍稀植物。由于四合木极易燃烧,当地居民称其为“油柴”。 通过对四合木内可能存在的“油”成分进行了分析,我们发现其茎组织含有大量的三脂酰甘油(Triacylglycerols),含量达到46 mg/g DM。在韧皮部中更高,达到90 mg/g DM。我们通过半薄切片对四合木中三脂酰甘油在不同组织的分布和存在形式进行了研究,发现三脂酰甘油主要以油体形式存在于木质部和韧皮部的薄壁组织中。在韧皮部中,几乎所有的薄壁细胞都含有大量的油体。 三脂酰甘油在植物的生长发育中起着非常重要的作用。作为植物生长发育所需的碳源和能量,三脂酰甘油一般储存在植物的种子和果实中。虽然也有关于其在茎和叶中发现的报道,但是含量很少。四合木茎组织含有大量的三脂酰甘油,这种现象可能与四合木茎中存在茎特异油脂合成酶系统有关。因此,克隆相关基因并在作物中表达,将对能源植物的开发具有重要意义。

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非晶状体βγ晶状体蛋白与三叶因子蛋白复合物(non-lens βγ-crystallin and trefoil factor complex,βγ-CAT)是一个从大蹼铃蟾(Bombina maxima)皮肤分泌物中分离的大然分子量为72kDa的全新的蛋白复合物.本研究测定了βγ-CAT处理红细胞后引起细胞内钾离子外流与溶血效应的时效曲线,结合扫描电子显微镜和透射电子显微镜分析βγ-CAT处理红细胞引起的早期形态学变化.结果表明:βγ-CAT(3 nmol/L)37℃处理红细胞5 min,(93.31±5.89)%的细胞内钾离子迅速外流(P<0.01),相心溶解率为(13.12±1.92)%(P<0.05).电子显微镜观察发现红细胞形态发生明显变化,细胞体枳增加,肿胀.少数红细胞表面向外形成棘状异常突起,部分肿胀细胞内的血红蛋白通过棘状突起缺口向细胞外喷射血红蛋白.表明βγ-CAT通过在红细胞膜上形成孔道使细胞内钾离子迅速外流导致红细胞内渗透压改变而溶血.其结果为理解βγ-CAT的溶血机制提供了直接的形态学证据.