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排序方式: 共有111条查询结果,搜索用时 15 毫秒
1.
Many studies demonstrate differences in the coverage of citing publications in Google Scholar (GS) and Web of Science (WoS). Here, we examine to what extent citation data from the two databases reflect the scholarly impact of women and men differently. Our conjecture is that WoS carries an indirect gender bias in its selection criteria for citation sources that GS avoids due to criteria that are more inclusive. Using a sample of 1250 U.S. researchers in Sociology, Political Science, Economics, Cardiology and Chemistry, we examine gender differences in the average citation coverage of the two databases. We also calculate database-specific h-indices for all authors in the sample. In repeated simulations of hiring scenarios, we use these indices to examine whether women's appointment rates increase if hiring decisions rely on data from GS in lieu of WoS. We find no systematic gender differences in the citation coverage of the two databases. Further, our results indicate marginal to non-existing effects of database selection on women's success-rates in the simulations. In line with the existing literature, we find the citation coverage in WoS to be largest in Cardiology and Chemistry and smallest in Political Science and Sociology. The concordance between author-based h-indices measured by GS and WoS is largest for Chemistry followed by Cardiology, Political Science, Sociology and Economics. 相似文献
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Chandrawati Kumari Bijo Varughese Siddarth Ramji Seema Kapoor 《Indian journal of clinical biochemistry : IJCB》2016,31(4):414-422
Pre analytical process of extraction for accurate detection of organic acids is a crucial step in diagnosis of organic acidemias by GCMS analysis. This process is accomplished either by solid phase extraction (SPE) or by liquid–liquid extraction (LLE). Both extraction procedures are used in different metabolic laboratories all over the world. In this study we compared these two extraction procedures in respect of precision, accuracy, percent recovery of metabolites, number of metabolites isolated, time and cost in a resource constraint setup. We observed that the mean recovery from SPE was 84.1 % and by LLE it was 77.4 % (p value <0.05). Moreover, the average number of metabolites isolated by SPE and LLE was 161.8 ± 18.6 and 140.1 ± 20.4 respectively. The processing cost of LLE was economical. In a cost constraint setting using LLE may be the practical option if used for organic acid analysis. 相似文献
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Mathias Weske Jens Hündling Dominik Kuropka und Hilmar Schuschel 《Informatik - Forschung und Entwicklung》1998,13(4):179-195
Zusammenfassung. Dieser Beitrag enth?lt die wesentlichen konzeptionellen überlegungen zur Entwicklung eines flexiblen Workflow-Management-Systems.
Ausgehend von einer Diskussion m?glicher Modellierungsalternativen wird unter Verwendung objektorientierter Modellierungstechniken
ein Workflow-Meta-Schema entwickelt, das die relevanten Entit?ten klassifiziert und ihre Beziehungen abbildet. Anhand eines
Beispiels werden die getroffenen Entwurfentscheidungen ausführlich begründet. Schlie?lich werden Zust?nde und Zustandsüberg?nge
von Workflow-Instanzen beschrieben, und es wird diskutiert, wie dynamische Ver?nderungen von Workflows zur Laufzeit durchgeführt
werden k?nnen, um laufende Workflows dynamisch an ver?nderte Umweltbedingungen anzupassen.
Eingegangen am 20. Dezember 1997 / Angenommen am 24. Juli 1998 相似文献
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Tony Monnet Mathias Samson Anthony Bernard Laurent David Patrick Lacouture 《Sports Engineering》2014,17(3):171-181
Current trends in swimming biomechanics are focused on accurate measurements. Nowadays, reliable calibration methods have been proposed to reach an accuracy of about 1 mm on rigid structure. But the question remains about the final accuracy for three-dimensional hand kinematics measurement during the underwater phase of front crawl swimming. Furthermore, most research is based on manual tracking with two or more cameras. In this paper we propose a protocol to acquire three-dimensional hand kinematics when swimming in a specific pool with a motion analysis system behind windows. Results highlight the benefits of using such a system in terms of accuracy and feasibility: the time allowed for post-processing is ten times lower and the quantified improved accuracy is better than with manual tracking. 相似文献
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The purpose of this article is to provide an overview of how the employees of higher education institutions perceive the impact of external evaluations. The study was conducted using the concurrent mixed method and involved 361 employees from Estonian universities and professional higher education institutions. The results indicated that evaluation is mostly deemed necessary at the levels of the organisation and the system; from the personal viewpoint of an employee, positive effects of external evaluations are perceived to a lesser degree. The negative influences mentioned were increased bureaucracy, extra work and stress. Top managers of institutions most often saw the positive influences from external evaluations since they help to implement reorganisations and development activities within an organisation. Managers perceived the positive effects of external evaluations on their everyday work as well, more than other employees did. Researchers felt the positive effects of external evaluations least. Nearly a quarter of all employees of higher education institutions do not perceive the effects of external evaluations on their everyday work at all. Employees of professional higher education institutions perceive the positive effects of external evaluations to a greater extent than employees of universities do, indicating that external evaluation has contributed to the development of their organisations. The differences in opinions of the employees of higher education institutions regarding perceived positive and negative impacts of external evaluations—whether on individual, organisation or system points of view—indicate that employees do not identify closely enough with the organisation and its strategic goals. 相似文献
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Seema Gupta Rajesh Pandey Ranjan Katyal H. K. Aggarwal R. P. Aggarwal S. K. Aggarwal 《Indian journal of clinical biochemistry : IJCB》2005,20(1):67-71
The present study was conducted to evaluate some of the components of antioxidant defense system and oxidative damage in 20
male patients of alcoholic liver disease (ALD). The results were compared with 20 healthy male smokers and 20 healthy male
non-smokers volunteers. Patients were subjected to detailed clinical examination and laboratory investigations. Blood samples
were collected for estimating reduced glutathione (GSH), total thiols (T-SH) malondialdehyde (MDA), transaminases (AST, ALT),
glutathione-S-transferease (GST) and gammaglutamyl transferase (GGT). Serum aspartate amino transferase (AST)/alanine amino
transferase (ALT) ratio was significantly (p<0.01) reduced in ALD patients as compared to the controls. However, the core
of utility of MDA and GST was found to be significantly (p<0.01) increased in ALD patients compared to controls. There was
a significant negative correlation of MDA with both GSH and TSH. Plasma GGT levels were significantly (p<0.01) increased in
alcoholics and the enzyme showed a significant positive correlation with MDA. These results give enough evidence of increased
oxidative stress and compromised antioxidant defense system in patients with ALD. 相似文献
10.
Seema Bhargava Meghaa Shanta Bhargava Eishaan Kamta Bhargava LM Srivastava 《Indian journal of clinical biochemistry : IJCB》2016,31(2):148-151
Hyperhomocysteinemia (HHCY) has been demonstrated to affect cochlear microvasculature as well as cochlear epithelial cells directly, with a resultant alteration of the expression of matrix metalloproteinases (MMPs) and their inhibitors, tissue inhibitors of metalloproteinases (TIMPs). Hence, ascertaining the optimum concentration of MMPs and TIMPs in the cochlea could help to inhibit hearing loss due to HHCY by the administration of appropriate MMP inhibitors, Since infections/inflammations as well as ototoxic antibiotics have a similar mechanism of otic pathology, the cochlear damage they cause could also be similarly prevented. 相似文献