身份认同与自我意识——《日常家当》的人物分析

美国著名女作家艾丽斯·沃克在小说《日常家当》中,通过一个受过高等教育的在外边世界获得＂成功＂的黑人姑娘迪＂衣锦还乡＂,探访在偏僻乡村的母亲和妹妹玛吉的故事,探讨美国黑人的自我意识和种族身份,并号召黑人积极把握自我,团结友爱,在美国社会中确立真正的人的地位。     

Tumor-derived angiogenesis factors from rat Walker 256 carcinoma: an experimental investigation and review

Summary Angiogenesis, the process of developing a hemovascular network, is an essential feature of the growth of solid tumors, and is induced by factors secreted by tumor cells. Assay procedures suitable for the investigation of angiogenesis, and for the screening of angiogenesis factors during purification are reviewed; and a number of reports describing the purification of angiogenesis factors, primarily from the rat Walker 256 carcinoma as starting material, are discussed. Work from the authors' laboratory is also presented. Walker 256 cells grown in large-scale culture were the source of a reproducible and homogeneous source of angiogenic material. Factors secreted by these cells were isolated by a series of chromatographic steps. Ion exchange chromatography on carboxymethyl-Sephadex produced two active fractions, one of which was fractionated into several macromolecular species by lectin affinity and hydrophobic adsorption chromatography. The other gave a high mol.wt, active fraction that was resolved into a low mol.wt, active component and a non-angiogenic but possibly carrier molecule with a mol.wt of 140,000. While none of the angiogenic factors were identified chemically, the results demonstrate the existence of both high and low mol.wt tumor-secreted angiogenic substances, confirming the hypothesis for tumor-induced angiogenesis and predicting potential means to interfere with the process of tumor growth.This work was supported by funds from the Monsanto Company under Agreements with Harward University and from the U.S. Public Health Service, Contract No. N01-CB-43942. We are particularly indebted to Bernard S. Wildi and Monte C. Throdahl for their advice, cooperation, and encouragement. We also thank Dr Judah Folkman for the initial supply of male mouse submaxillary glands and rat Walker carcinoma conditioned medium, for help with the CAM assays, assays in the rabbit cornea, and many helpful discussions; and R. Bretton, A. Ehrlich, B. Evans, F. Fu, N. Hay and B. Tsokanis for excellent technical assistance.Author to whom correspondence should be addressed.     

中国赤眼蜂科二新种及一新纪录属新纪录种（膜翅目：小蜂总科）

记述了赤眼蜂科Ｔｒｉｃｈｏｇｒａｍｍａｔｉｄａｅ缨翅赤眼蜂属ＭｅｇａｐｈｒａｇｍａＴｉｍｂｅｌａｋｅ和寡索赤眼蜂属ＯｌｉｇｏｓｉｔａＷａｌ中二新种；异索缨翅赤眼蜂Ｍｅｇａｐｈｒａｇｍａ ａｎｏｍａｌｉｆｕｎｉｃｕｌｉ，ｓｐ．ｎｏｖ．和黑翅寡索赤蜂Ｃｈａｅｔｏｓｔｒｉｃｈｅｌｌａ ｐｕｎｇｅｎｓ（Ｍａｙｒ）模式标本存于沈阳农业大学，纪录种：彭根多毛赤蜂Ｃｈａｅｔｏｓｔｒｉｃｈｅｌｌａ ｐｕｎｇｅｎｓ     

竹蝗属(Ceracris Walker)的支序系统学和生物地理学研究

以黄脊雷蓖蝗为外群，选择20个形态性状对竹蝗属10个种(亚种)的系统发育关系进行分析，并据此探讨了其区系形成．结果表明：竹蝗属可以分为长翅和短翅两个类群，短翅类群包括蒲氏竹蝗、黑翅竹蝗和思茅竹蝗；形态分类中归为短翅类群的贺氏竹蝗是长翅类群中的一个高度特化的种类；中国的西南地区是竹蝗属的分布中心，同时也是其起源和物种分化中心。     

三化螟的简易测报和综合防治

为防治三化螟（Ｔｒｙｐｏｒｙｚａ ｉｎｃｅｒｔｕｌａｓ Ｗａｌｋｅｒ）为害水稻，以柳州市太阳村镇为例，探讨三化螟的预测方法和综合防治方法。     

蜀柏毒蛾两天敌Holling捕食模型的参数分析

本文利用Holling模型分析了厉蝽(Cantheconidea concinna Walker)、广腹螳螂(Hierodula potellifera Serville)两捕食性天敌与蜀柏毒蛾幼虫之间的功能性反应.结果表明:厉蝽、广腹螳螂是蜀柏毒蛾的两种重要捕食性天敌,最大日捕食量每头可达22.42头和24.63头,两者在控制蜀柏毒蛾危害中起着重要的作用.     

粘虫生物学特性及生命表研究

以万源县第二代粘虫为研究对象,依据颜色变化将卵分为4级;依据复眼色泽、体色和翅芽变化将蛹分为5级.确定了头宽值的幼虫分龄标准,并认为粪粒大小和体长也可作为分龄的参考标准.建立了卵块大小(X)与含卵量(Y)的关系Y=20.38+4.261 4X.讨论了各虫态的习性、历期及发育进度等生物学特性.建立了实验种群特定年龄生命表.世代死亡率为82%,卵、幼虫、蛹和成虫期的死亡率分别为8%,55.54%,19.75和50.61%.种群增长指数I=0.423 7,分析了种群数量减少的原因.     

The responses of East Asian Summer monsoon to the North Atlantic Meridional Overturning Circulation in an enhanced freshwater input simulation

We investigated the response of the East Asian Summer Monsoon （EASM） to a weakened Atlantic Meridional Overturning Circulation （AMOC） and its mechanism in an enhanced freshwater input experiment （FW） by using a fully-coupled climate model. The response was a weakened EASM and the mechanisms can be explained as follows. The simulated weakened AMOC resulted in a drop in sea surface temperature （SST） in the North Atlantic （NA） and, correspondingly, an anomalous high sea level pressure （SLP） over the North American regions, which in turn increased the northeast surface winds across the equator in the eastern tropical Pacific （ETP）. The anomalous northeast winds then induced further upwelling in the ETP and stronger air/sea heat exchange, therefore leading to an anomalous cooling of the eastern tropical sea surface. As a result, the climatologic Hadley Circulation （HC） was weakened due to an anomalous stronger sinking of air in the ETP north of the equator, whereas the Walker Circulation （WC） in the western tropical Pacific （WTP） north of the equator was strengthened with an eastward-shifted upwelling branch. This feature was in agreement with the anomalous convergent winds in the WTP, and led to a weakened EASM and less East Asian summer precipitation （EASP）. Furthermore, comparison with previous freshwater experiments indicates that the strength of EASP could be influenced by the magnitude of the added freshwater.