西北太平洋柔鱼渔场变化与黑潮的关系

柔鱼是北太平洋海域的重要经济头足类,黑潮的变化直接影响着柔鱼渔场形成及其空间分布。利用1998-2007年黑潮分布类型,结合同期8-10月我国鱿钓渔船生产数据,分析北太平洋柔鱼渔场变化与黑潮分布的关系。在25°～40°N、125°～150°E海域内,以空间分布率经纬度5°×5°为一个空间单元,共分A(140°～145°E、35°～40°N)、B(145°～150°E、35°～40°N)、C(135°～140°E、30°～35°N)、D(140°～145°E、30°～35°N)和E(145°～150°E、30°～35°N)5个区,将黑潮分布类型分为大弯曲型、小弯曲型和平直型3种。利用渔场重心的纬度向变化作为柔鱼渔场变动的指标。研究认为,A区黑潮分布特征对柔鱼渔场重心纬度影响最大,其次为B区和C区,而其它区影响则不明显。A区出现黑潮大弯曲型时,柔鱼渔场重心明显偏北且概率高;小弯曲型或平直型时,柔鱼渔场重心明显偏南。研究认为,黑潮流轴的走向影响着柔鱼渔场的空间分布。     

磁化海水在对虾育苗中的应用研究

经过磁场处理的海水;应用在中国对虾人工育苗和短期养成的研究中,产生了良好的生物效应,使用1600G、2400G、3000G三种磁感应强度的磁化装置处理的海水,对于仔虾的成活率都有较明显的提高,平均提高17.90％;在对虾短期养成(室内)中,使成活率和体长都比对照高,平均提高51.88％和10.56％。这主要因为     

基于意愿价值评估法的三门湾资源环境非使用价值研究

通过问卷调查和意愿价值评估法,对三门湾资源环境的非使用价值进行研究。调查问卷分三门湾环境现状、三门湾环境保护和调访者基本情况3大部分,随机选取沿岸居民、企业员工、政府官员、学校教师等,发放调查问卷300份,有效回收294份。结果显示,三门湾资源环境个人平均支付意愿(WTP)为89.25元/(人.年)。以2006年当地人口统计数为总体进行估算,三门湾资源环境非使用价值为4 632.36万元/年,其中存在价值为2 501.47万元/年,遗产价值为1 389.7万元/年,选择价值为741.19万元/年。支付意愿影响因素分析表明,支付意愿与居民受教育程度、收入呈正相关;与年龄呈负相关(P<0.05)。意愿支付率与意愿支付额的影响因素不同,意愿支付率与当地经济收入组成有关,研究中象山县为最高,意愿支付额则更与当地经济发展水平密切相关,宁海县在本研究中为最高。     

The debate on a loss of biodiversity: can we derive evidence from the monitoring of major plant pests and diseases in major crops?

Journal of Plant Diseases and Protection - The European commission directive EC 128/2009 calls for monitoring pests and pathogens of major crops. The monitoring data may be analysed for trends over...     

龙爪槐正己烷提取物对铜绿微囊藻抑制机理的研究(英文)

[目的]对前期研究发现的具有显著抑制铜绿微囊藻的龙爪槐正己烷提取物进行抑制机理分析。[方法]采用龙爪槐正己烷提取物处理铜绿微囊藻,通过考察铜绿微囊藻的叶绿素a含量、蛋白质含量及细胞膜透性和SOD活性,初步分析龙爪槐提取物对铜绿微囊藻抑制作用的机理。[结果]龙爪槐正己烷提取物破坏铜绿微囊藻的细胞膜系统,增加细胞膜透性;叶绿素a和蛋白质含量在培养7d后分别减少为对照组的10%和50%左右,对藻细胞的光合反应系统造成破坏;另外,藻细胞的SOD活性在龙爪槐正己烷粗提物作用下,在初期呈现为应激性上升,在后期表现为抑制的阶段性变化。[结论]龙爪槐正己烷提取物抑制铜绿微囊藻的可能机理是:破坏细胞膜,使膜通透性增大;破坏光合反应系统,造成光和色素和蛋白质含量减少;SOD活性发生阶段式变化。     

三疣梭子蟹卵巢发育期间Y器官组织学变化

通过活体解剖和组织切片技术,系统研究了三疣梭子蟹卵巢发育过程中Y器官的外观和组织学结构变化。结果表明,三疣梭子蟹Y器官为淡黄色、扁平球状,其中分布有血窦和血管,腺细胞细胞质染色不明显,细胞核呈卵圆形,嗜碱性较强。卵巢发育过程中,Y器官组织学具有以下特征和变化:Ⅰ期,血窦和血管清晰可见,分布于血窦附近的腺细胞膨大呈泡状,且细胞核直径显著大于内部的细胞核直径(P<0.01);Ⅱ期,血管收缩,腺细胞体积变小,胞核直径减少为(3.64±0.62)μm(P<0.01);Ⅲ期,血窦边界模糊,呈退化状态,细胞核呈强嗜碱性;Ⅳ期,Y器官小叶间的空隙变大,腺细胞边界消失,很难发现核仁;Ⅴ期,Y器官小叶间的空隙进一步变大,细胞核直径进一步缩小、核膜皱缩。以上结果表明,三疣梭子蟹卵巢发育过程中,Y器官呈退化的非分泌状态,因此,Y器官可能没有参与卵巢发育的内分泌调控。     

温度和相对饵料丰度对海蜇水母体生长的影响

本文在实验室条件下,盐度为20‰时就温度和相对饵料丰度对海蜇(Rhopilema esculenta Kishinouye)水母体生长的影响进行研究。温度设6个梯度组(16℃,20℃,24℃,28℃,32℃、变温),同时对应4级饵料丰度(20℃组设7级),通过测定海蜇水母体日生长率得出海蜇水母体生长的最适温度,最佳有效饵料丰度及变温组的适宜饵料丰度,并在20℃条件下,得出水母体平均日生长率(Y)与相对饵料丰度(X)的关系式:Y=9.43-2.69(1 X~-),从理论上推算出水母体平均日生长率的最大值为9.34%及停止生长(或出现负生长)时的饵料丰度为0.285次/日。实验用逐步逼近方法得到海蜇水母体致死的上限温度为34℃。     

Computed tomography or rhinoscopy as the first-line procedure for suspected nasal tumor: A pilot study

There are no evidence-based guidelines as to whether computed tomography (CT) or endoscopy should be selected as the first-line procedure when a nasal tumor is suspected in a dog or a cat and only one examination can be performed. Computed tomography and rhinoscopic features of 17 dogs and 5 cats with a histopathologically or cytologically confirmed nasal tumor were retrospectively reviewed. The level of suspicion for nasal neoplasia after CT and/or rhinoscopy was compared to the definitive diagnosis. Twelve animals underwent CT, 14 underwent rhinoscopy, and 4 both examinations. Of the 12 CT examinations performed, 11 (92%) resulted in the conclusion that a nasal tumor was the most likely diagnosis compared with 9/14 (64%) for rhinoscopies. Computed tomography appeared to be more reliable than rhinoscopy for detecting nasal tumors and should therefore be considered as the first-line procedure.     

Microalgae n-3 PUFAs Production and Use in Food and Feed Industries

N-3 polyunsaturated fatty acids (n-3 PUFAs), and especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are essential compounds for human health. They have been proven to act positively on a panel of diseases and have interesting anti-oxidative, anti-inflammatory or anti-cancer properties. For these reasons, they are receiving more and more attention in recent years, especially future food or feed development. EPA and DHA come mainly from marine sources like fish or seaweed. Unfortunately, due to global warming, these compounds are becoming scarce for humans because of overfishing and stock reduction. Although increasing in recent years, aquaculture appears insufficient to meet the increasing requirements of these healthy molecules for humans. One alternative resides in the cultivation of microalgae, the initial producers of EPA and DHA. They are also rich in biochemicals with interesting properties. After defining macro and microalgae, this review synthesizes the current knowledge on n-3 PUFAs regarding health benefits and the challenges surrounding their supply within the environmental context. Microalgae n-3 PUFA production is examined and its synthesis pathways are discussed. Finally, the use of EPA and DHA in food and feed is investigated. This work aims to define better the issues surrounding n-3 PUFA production and supply and the potential of microalgae as a sustainable source of compounds to enhance the food and feed of the future.