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31.
32.
中国木犀属小志 总被引:1,自引:0,他引:1
陆瑞琳 《中国科学院研究生院学报》1989,27(1):71-74
In the present paper a new species, Osmanthus gracilinervis Chia ex R. L.
Lu, is described from Guangxi. The new species is also distributed in Guangdong, Jiangxi,
Zhejiang, Hunan and Sichuan. Based on the analysis of a great deal of specimens, eight spe-
cies, i.e. Osmanthus corymbosus H. W. Li, O. longispermus H. T. Chang, O. angustifolius H.
T. Chang, O. triandrus H. T. Chang, O. longicarpus H. T. Chang, O. omeiensis Fang ex H.
T. Chang, O. nanchuanensis H. T. Chang and 0. cylindricus H. T. Chang, are reduced as
the synonyms of O. marginatus (Champ. ex Benth.) Hemsl. var. marginatus. O. longissimus
H. T. Chang and O. pachyphyllus H. T. Chang are respectively reduced to varieties of O.
marginatus, i.e.O. marginatus var. longissimus (H.T. Chang) R. L. Lu and var. pachy-
phyllus (H. T.Chang) R. L. Lu. And finally O. maximus H. T. Chang is treated in this
paper as a synonym of O. matsumuranus Hayata. 相似文献
33.
Amitabha Ray Anil Kumar Bahadur S. L. Dayalu Naik Bhuvnesh Kumar Sharma 《Indian journal of clinical biochemistry : IJCB》2001,16(2):199-202
Endogenous oestrogens are thought to be involved in breast cancer, but few studies could show the direct relationship between
hormones and pathological process of the disease. In the present study, oestradiol was estimated in the serum of pre-and postmenopausal
breast cancer patients along with normal healthy controls and patients with carcinoma of the uterine cervix which is not dependent
on oestrogens. Premenopausal patients with breast cancer showed higher levels of oestradiol as compared to premenopausal control
women as well as cervical cancer patients. Whereas, no statistically significant differences were observed in serum oestradiol
levels amongst postmenopausal groups of breast cancer, cervical cancer and normal women. The result of the study reflects
the association of oestradiol as well as its difference in the pathological events of pre and postmenopausal breast cancer. 相似文献
34.
合作网络中心性指标越来越多地被应用于科研团队学术带头人的识别,但识别的合理性与有效性有待论证。基于此,归纳科研团队学术带头人的胜任特征,并分析合作网络中心性指标测度这些胜任特征的合理性。以14个受资助的国家自然科学基金创新研究群体为对象,从识准率和识全率两个方面对网络中心性指标识别科研团队学术带头人的有效性进行实证分析。 相似文献
35.
本文简介了“全球农情遥感速报系统”的基本情况,包括作物长势监测、主要作物产量预测、粮食产量预测、时空结构监测和粮食供需平衡预警等五个子系统。具体介绍了该系统提供的信息产品的应用,包括国内外农作物长势监测、作物和粮食产量估算、种植结构监测、复种指数监测以及旱情监测等内容;同时就系统应用时存在的问题提出了建议。 相似文献
36.
西部地区现代信息服务业发展现状与对策研究 总被引:1,自引:0,他引:1
大力发展现代信息服务业是西部地区实现跨越式发展的最佳途径和必然趋势。文章分析了西部地区现代信息服务业的发展现状,并针对问题提出了具体的对策建议。 相似文献
37.
通过对全国范围内的211高校图书馆资源现状进行分析,认为产生高校图书馆资源不均衡现象的原因主要有政治、经济、人口、文化发展的历史等。同时针对图书馆资源不均衡现象提出了一些改进措施。 相似文献
38.
Dara J. Glasser Kenneth W. Goodman Norman G. Einspruch 《Ethics and Information Technology》2007,9(2):101-109
Radio Frequency Identification (RFID) systems identify and track objects, animals and, in principle, people. The ability to
gather information obtained by tracking consumer goods, government documents, monetary transactions and human beings raises
a number of interesting and important privacy issues. Moreover, RFID systems pose an ensemble of other ethical challenges
related to appropriate uses and users of such systems. This paper reviews a number of RFID applications with the intention
of identifying the technology’s benefits and possible misuses. We offer an overview and discussion of the most important ethical
issues concerning RFID, and describes and examine some methods of protecting privacy.
Norman G. Einspruch serves as a consultant to several high-technology companies, one of which is in the RFID components and
systems business. 相似文献
39.
Artificial Life (ALife) has two goals. One attempts to describe fundamental qualities of living systems through agent based
computer models. And the second studies whether or not we can artificially create living things in computational mediums that
can be realized either, virtually in software, or through biotechnology. The study of ALife has recently branched into two
further subdivisions, one is “dry” ALife, which is the study of living systems “in silico” through the use of computer simulations,
and the other is “wet” ALife that uses biological material to realize what has only been simulated on computers, effectively
wet ALife uses biological material as a kind of computer. This is challenging to the field of computer ethics as it points
towards a future in which computer and bioethics might have shared concerns. The emerging studies into wet ALife are likely
to provide strong empirical evidence for ALife’s most challenging hypothesis: that life is a certain set of computable functions
that can be duplicated in any medium. I believe this will propel ALife into the midst of the mother of all cultural battles
that has been gathering around the emergence of biotechnology. Philosophers need to pay close attention to this debate and
can serve a vital role in clarifying and resolving the dispute. But even if ALife is merely a computer modeling technique
that sheds light on living systems, it still has a number of significant ethical implications such as its use in the modeling
of moral and ethical systems, as well as in the creation of artificial moral agents. 相似文献
40.
This study investigated how peer perceptions of teacher liking and disliking for a student shape students’ social cognitions by moderating associations between the student’s peer-perceived social behavior and peer liking and disliking status. We studied individual teacher liking and disliking as well as classroom norms as moderators of individual and classroom-level behavior-status associations. Peer nominations of (dis)liking, being (dis)liked by the teacher, and prosocial and aggressive behavior were gathered from 1454 students (Mage = 10.60) in 58 fifth-grade classes in the Netherlands. Results from multilevel analyses showed the teacher made a difference in particular for those students who were at-risk of low peer status, that is, those students who were perceived by many of their peers to show aggressive behavior and by few to show prosocial behavior. These students were disliked less and liked more when they were perceived by peers to be less disliked and more liked by the teacher. Furthermore, the amount of disliking associated with overt and relational aggression differed across classrooms, depending on norms of teacher liking. These findings may help teachers to understand and improve an individual student’s peer status, and alter the behavior–status dynamics in their class. 相似文献