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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
941.
942.
943.
企业众包模式参与效果影响因素研究 总被引:1,自引:0,他引:1
以参与网络众包的企业为研究对象,基于企业动态能力理论、认知理论和激励理论,分析企业的自身属性、动态能力以及客观条件等对众包参与效果的影响,在此基础上提出了研究假设,从而构建了研究的概念模型,然后采用问卷调查的方法对企业众包模式的参与效果开展调研,并运用结构方程模型进行了实证检验。实证结果表明:企业自身属性中的高参与会有效促进企业提升其参与绩效;企业动态能力对企业参与众包效果的促进作用不明显;企业在众包方面的相关经验等客观条件对企业参与众包的效果有明显的促进作用。 相似文献
944.
Ishrat Kareem S. A. Jaweed J. S. Bardapurkar V. P. Patil 《Indian journal of clinical biochemistry : IJCB》2004,19(2):124-127
The present study was undertaken in 100 subjects, 30 diabetics without complication (group I), 40 diabetics with retinopathy
(group II) and 30 non diabetic as normal control group (group III). Blood sugar levels, magnesium, cholesterol and triglyceride
were analyzed from plasma and serum. The results were correlated with degree of diabetic control from the levels of glycosylated
hemoglobin. Serum magnesium levels in group II were found to be significantly lowered than in group I. There was also significant
difference in magnesium levels of group I and group III. We found a significant correlation between the glycosylated hemoglobin
and magnesium levels in our study.
The results also indicate that the patients with diabetic retinopathy showed significant rise in serum cholesterol and triglyceride.
Probably hypomagnesemia and increased serum cholesterol and triglyceride levels are responsible for microvascular changes
in diabetes leading to retinopathy. The purpose of this study was thus to gather information about the degree of control of
diabetes and magnesium status. 相似文献
945.
946.
Curcumin is a natural anti-inflammatory and antioxidant with several potential health benefits. Although it has been examined in several metals toxicity studies, but its role in the protection against copper toxicity has not been investigated. In this study; the detoxification and antioxidant effect of curcumin were examined to determine its prophylactic/therapeutic role experimentally in rats. Forty albino rats were divided into five groups; control, CuSO4 (4 mg/kg body weight), curcumin (80 mg/kg body weight), curcumin post-treatment (CuSO4 for 15 days followed by curcumin for the next 15 days) and curcumin co-treatment (CuSO4 plus curcumin for 30 days). All rats were treated orally by stomach tube for 30 days/once a day. Changes were observed in hepatic marker enzymes such as: aspartate aminotransferase (AST), alanine transaminase-(ALT), alkaline phosphatase (ALP) and gamma-glutamyltransferase (GGT), besides the serum total protein, urea and creatinine. Concentration of liver and kidney antioxidants such as: catalase (CAT), superoxide dismutase (SOD), reduced glutathione-(GSH) and malondialdehyde (MDA) were measured. An increased in the activities of liver marker enzymes, urea, creatinine and the MDA contents were detected after exposure to CuSO4. Meanwhile, the activities of serum total protein, hepatic and renal antioxidants were decreased. Changes in all biochemical parameters were alleviated by the post-treatment and co-treatment of curcumin. Our finding suggests that the curcumin showed protective effects on CuSO4-induced hepatotoxicity and nephrotoxicity. 相似文献
947.
Mark Coeckelbergh 《Ethics and Information Technology》2007,9(3):219-231
Many philosophical and public discussions of the ethical aspects of violent computer games typically centre on the relation
between playing violent videogames and its supposed direct consequences on violent behaviour. But such an approach rests on
a controversial empirical claim, is often one-sided in the range of moral theories used, and remains on a general level with
its focus on content alone. In response to these problems, I pick up Matt McCormick’s thesis that potential harm from playing
computer games is best construed as harm to one’s character, and propose to redirect our attention to the question how violent
computer games influence the moral character of players. Inspired by the work of Martha Nussbaum, I sketch a positive account
of how computer games can stimulate an empathetic and cosmopolitan moral development. Moreover, rather than making a general
argument applicable to a wide spectrum of media, my concern is with specific features of violent computer games that make
them especially morally problematic in terms of empathy and cosmopolitanism, features that have to do with the connections
between content and medium, and between virtuality and reality. I also discuss some remaining problems. In this way I hope
contribute to a less polarised discussion about computer games that does justice to the complexity of their moral dimension,
and to offer an account that is helpful to designers, parents, and other stakeholders.
An earlier version of this paper was presented at the ACLA 2006 conference in Princeton, 25 March 2006. 相似文献
948.
Conventional information retrieval technology (i.e. VSM) faces many difficulties when being implemented in complex P2P systems for the lack of global statistic information (e.g. IDF) and central services. In this paper, we suggest a novel query optimization scheme (Semantic Dual Query Expansion, SDQE) that makes full use of the context information supplied by the local document collection. Latent Semantic Indexing (LSI) is used to explore the local context information. By comparing the different local context information hidden in different document collections, it is possible to solve the synonymy–polysemy problem in VSM. The experiments prove that our scheme is effective to improve the retrieval performance in P2P systems without knowing the global statistic information. 相似文献
949.
M. Maneesh Sanjiba Dutta Amit Chakrabarti D M Vasudevan 《Indian journal of clinical biochemistry : IJCB》2007,22(1):138-142
Infertility is well-established harmful effect in chronic alcoholism and so far, there is no effective treatment for this
condition. The study was conducted to determine the effects of alpha tocopherol on ethanol induced testicular injuries in
male albino rats of Wistar strain. Five groups (n=6) of animals were used. Group I served as control. Group II received daily
1.6g ethanol/kg body weight/day for 4 weeks orally. Group III received 1.6g ethanol+80mg alpha tocopherol/kg body weight/day
for four weeks orally. Group IV received 1.6g ethanol/kg body weight for/day 4 weeks and followed by 80mg alpha tocopherol/kg
body weight/day for four weeks orally. Group V received 1.6g ethanol/kg body weight/day orally for 4 weeks, followed by 4
weeks abstinence. Twently-four hours after the last treatment the rats were sacrificed using anesthetic ether. Testes were
removed and used for the estimation of extent of lipid peroxidation and tissue levels of antioxidants and steroidogenic enzymes.
Alpha tocopherol treatment increased the activities of testicularΔ
5, 3β-HSD. Moreover, the treatment was also associated with significant decrease in testicular oxidative stress. Ethanol-induced
oxidative stress and decreased steroidogenesis can be reversed by treatment with alpha tocopherol. 相似文献
950.
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