Temporal changes in ascendance and in‐season exploitation of Atlantic salmon,Salmo salar,inferred by a video camera array

Abstract Weekly exploitation rates of Atlantic salmon, Salmo salar L., in the River Utsjoki, Finland, were estimated from catch reports during the 2003, 2004, 2006 and 2007 seasons, and recordings of all Atlantic salmon ascending the river using a submerged video camera array. In all years, mean weekly fishing mortality rates were significantly higher in June than July to August, with a falling trend throughout the fishing season. Owing to overlap in size between one‐sea‐winter (1SW) and multi‐sea‐winter (MSW) salmon, the estimated fishing mortality rates were based on all sea‐age categories combined. By the second week in June, 18.3–34.7% of large salmon (only MSW) had ascended, compared with 2.2–6.4% of small salmon (1SW and some MSW). Indirectly, the earlier start of ascent of large salmon to River Utsjoki indicated that in‐river fishing mortality of MSW salmon is higher than for 1SW salmon. A later opening of the fishing season may be used to reduce the in‐river fishing mortality, especially for the MSW component.     

基于多FPGA的片上网络模拟平台设计和实现

针对片上网络的设计和优化问题，提出了一种基于多FPGA的片上网络模拟平台结构，用于加速片上网络的功能验证和性能评估.通过层次化设计和分布式流量管理器等技术，有效地提高了系统的灵活性，加速了片上网络的设计空间搜索.实验结果表明，多FPGA模拟平台不仅相对于传统的软件仿真具有500~10 000倍的加速比，与其他片上网络模拟平台相比也具有明显的速度优势.     

水稻越冬品系的杂种优势及配合力分析

对3个越冬品系与4个籼稻品种配制的16个正反交F1代主要农艺性状的杂种优势、母体效应值和按不完全双列杂交配制的12个正交组合及亲本主要农艺性状的配合力、遗传力进行了分析,结果表明:(1)所有组合的播始历期、株高和结实率具有超亲优势,千粒重接近中亲值.(2)所有组合的播始历期、每穗总粒数和结实率的母体效应值较高.(3)亲本SW-1 和R195的一般配合力(GCA)较好,其所配制组合的特殊配合力(SCA)效应值也较高;而SW-3和R128的GCA也较好,其所配制组合的SCA效应值却偏低;表明亲本的GCA效应与组合的SCA效应关联不大.(4)亲本的播始历期、株高、结实率、谷粒长、谷粒长宽比、千粒重6个性状的GCA基因型方差在基因型总方差中比重大于60%,且它们的H2N也均大于60%,说明这些性状遗传主要受基因加性效应的影响;而单株产量的SCA方差对总方差的贡献率大于60%,且它的H2N仅为18.83%,说明其遗传主要受基因非加性效应的影响.父本和母本对GCA方差的贡献率在所有性状表现上相差较大,母本GCA方差的贡献率远大于父本,且双亲的互作效应不明显.(5)利用越冬品系进行品种选育应注重对杂交后代株高、结实率和千粒重等性状的选择.     

陇东地区不同生态型冬小麦抗旱性研究与适宜品种的筛选

在不同的播前底墒下,应用抗旱指数法、隶属函数法、模糊综合评判法研究了14个不同生态类型旱地冬小麦品种的抗旱性。结果表明,随着底墒的增加,旱地冬小麦产量和水分利用效率显著提高,相同底墒下品种之间产量与水分利用效率差异显著,不同生态型冬小麦对播前底墒的反应明显不同。抗旱指数法、隶属函数法、模糊综合评判法均能较好地评价旱地冬小麦的抗旱性,其评价结果基本一致。参试品种从来源分析,抗旱性表现为:甘肃陇东>山西地区>北京地区>渭北旱塬>黄淮地区。     

活性氧抑制剂对绞股蓝皂苷抑癌作用的影响

【目的】研究活性氧清除剂N-乙酰半胱氨酸(NAC)对绞股蓝皂苷(Gypenosides,Gyp)作用下人结直肠癌SW620细胞生长抑制的作用。【方法】采用MTT法检测NAC对Gyp作用下SW620细胞增殖的影响;采用流式细胞仪观察NAC对Gyp处理的SW620细胞的线粒体膜电位、DNA片段生成及细胞凋亡的影响。【结果】NAC可以对抗Gyp对SW620细胞的增殖抑制;可解除Gyp诱导SW620细胞凋亡过程中引起的线粒体膜电位降低,从而抑制DNA片段生成的增加,进而抑制Gyp诱导的SW620细胞凋亡。【结论】Gyp在诱导SW620细胞凋亡的过程中启动了关键因子活性氧,从而导致线粒体膜电位下降、DNA损伤,并最终诱导细胞凋亡;活性氧抑制剂可以削弱这种影响。     

水稻越冬品系的耐冷性鉴定

以4个水稻越冬品系和4个籼稻品种(对照)为材料,检测了低温胁迫条件下水稻幼苗的生理生化特性。结果显示,经低温胁迫,越冬品系的幼苗存活率极显著高于对照品种,幼苗存活率最高的是SW-2(95.31%),最低的是对照品种桂99(1.67%),4个越冬品系平均幼苗存活率比4个对照品种高出71.12个百分点。低温胁迫后越冬品系的相对电导率小于对照品种,黄化幼苗的转绿能力强于对照品种。水稻幼苗在低温胁迫后丙二醛(MDA)含量都有所增加,但越冬品系比对照品种增加的量要少;越冬品系在低温胁迫后超氧化物歧化酶(SOD)相对活性比对照品种要高。因此,越冬品系具有很强的耐低温能力。     

悬浮物和冲击波造成的渔业资源损失量估算

以液化天然气（LNG）海洋工程环境影响评价为例,根据2004年5、8、11月和2005年5月在评价水域进行的渔业资源调查和LNG项目工程分析,评估工程施工期间悬浮物和冲击波对渔业资源的损失量。以往,采用直接鱼类重量损失进行评估,鱼卵、仔鱼和幼鱼潜在的生长价值无法体现,损失量被严重低估。本研究采用渔业资源尾数密度（包括鱼卵、仔鱼生长形成的部分）、受影响的面积和渔获物商品体重的乘积进行计算,可以避免上述缺陷。评价结果表明,LNG工程悬浮物对游泳能力较差的虾、蟹类影响远大于鱼类。以冲击波对鱼类影响为例,传统方法评价结果中的鱼类损失仅为43.39 t,明显低于本研究评价结果的201.9 t。     

优质杂交水稻泰丰优2098高产制种技术

优质杂交稻新品种泰丰优2098是福建省农业科学院水稻研究所引进广东省农业科学院水稻研究所选育的不育系泰丰A与自选恢复系福恢2098配组而成,具有米质优、丰产性好、适应性广等特点。介绍了泰丰优2098亲本的特征特性,并总结其高产制种关键技术。     

优质稻泰丰优2098在新罗区种植表现及高产栽培技术

泰丰优2098是用泰丰A与福恢2098配组育成的优质三系杂交稻新品种,于2012年通过福建省农作物品种审定。2013年龙岩市新罗区引种试种,表现生长势好、穗大粒多、结实率高、适应性广、稻米品质优等特点。介绍了泰丰优2098在新罗区种植表现及高产栽培技术。     

Covered catchment experiment at Gårdsjön: changes in runoff chemistry after four years of experimentally reduced acid deposition

Atmospheric deposition was almost entirely excluded from the forested headwater catchment G1 ROOF, by means of a 7000 m² plastic roof that prevents rain and throughfall from reaching the ground. Under the roof an irrigation system was installed to simulate a natural precipitation regime. The intercepted throughfall was substituted by the same amount of clean pre-industrial throughfall. The experiment started in April 1991. During the four years of the treatment, 2960 mm (18 600 m³) of sprinkled solution was applied under the roof, which is about 15 times the mean water storage of the catchment. After four years of treatment major changes in runoff chemistry were observed. The exclusion of all non-marine sulphate (SO₄ ^2–) input to the catchment (i.e. ca 75 % of total SO₄ ^2– input excluded) resulted in significant decline of sulphate in runoff through all four years of treatment. During the fourth year, annual volume weighted SO₄ ^2– concentration was 46 % lower than the two years prior to the treatment. Concentrations of inorganic aluminium Al³⁺ declined 52 % and Mg²⁺ declined 54 %. No change of H⁺ concentration was detected. As the treatment proceeds there seems to be a trend towards less negative acid neutralising capacity in runoff.