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541.
Landmarks     
Z. M. 《Prospects》1985,15(1):3-9
  相似文献   
542.
Landmarks     
Z. M. 《Prospects》1984,14(1):3-7
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This paper gives the results of the scientometric analysis of foreign publications by Kazakh authors that was reflected in the SCOPUS DB in 1991–2008. The publication activity is expressed in 3883 documents, the citation index of which is 10 132. The average share of Kazakh publications in the total worldwide flow is equal to 0.017%. The citation rate of publications was revealed to have significantly grown since the 1996–2000 period. It is shown that most articles were written in English and published in periodical editions. The main themes of publications are represented by physics and chemistry. The leading foreign partners of Kazakhstan in the scientific sphere were determined. Kazakh-Russian scientific cooperation is developing most fruitfully.  相似文献   
546.
Urine is a proven source of metabolite biomarkers and has the potential to be a rapid, noninvasive, inexpensive, and efficient diagnostic tool for various human diseases. Despite these advantages, urine is an under-investigated source of biomarkers for multiple sclerosis (MS). The objective was to investigate the level of some urinary metabolites (urea, uric acid and hippuric acid) in patients with MS and correlate their levels to the severity of the disease, MS subtypes and MS treatment. The urine samples were collected from 73 MS patients-48 with RRMS and 25 with SPMS- and age matched 75 healthy controls. The values of urinary urea, uric acid and hippuric acid in MS patients were significantly decreased, and these metabolites in SPMS pattern showed significantly decrease than RRMS pattern. Also showed significant inverse correlation with expanded disability status scale and number of relapses. Accordingly, they may act as a potential urinary biomarkers for MS, and correlate to disease progression.  相似文献   
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This paper studies the load mitigation problem for wind turbines by using active tuned mass dampers. A state space model for the tower/nacelle system is established with the consideration of tower/blade interaction. The uncertainties that appear in the damping matrix and natural frequencies are also considered in the controller design. External loads acting on the tower including the drag force induced by winds and the absolute base shear induced by the rotating blades are involved, and shaping filters for online generating these loads are proposed which can be easily implemented in numerical simulations. An adaptive sliding-mode controller is proposed to handle the system uncertainties, external disturbances and hard constraint, and also to improve the overall performance of the wind turbine system. Numerical simulations are performed to demonstrate the effectiveness of the proposed control law.  相似文献   
549.
The present study was undertaken to evaluate antidiabetic and antioxidant activities of Cayratia trifolia root extract against streptozotocin induced diabetes in experimental rats to scientifically validate its use against diabetes in some parts of India. Ethanolic extract, showing the highest activity in in vitro experiments, was prepared in saline and administered orally to streptozotocin induced albino Wistar diabetic rats for 21 days. Biochemical parameters liver and muscles glycogen and in vivo antioxidant activity in normal, diabetic control, standard (metformin) and treated animals were determined and compared. Attempt was made to isolate, purify and characterize one of the major secondary metabolites in extract by range of chromatographic and spectroscopic techniques. Treatment of streptozotocin induced diabetic rats with ethanolic root extract (500 mg/kg) caused significant (P < 0.01) reduction in blood glucose (312–178 mg/dL), increase in body weight (181–219 g) and serum insulin (1.28–2.26 IU/dL). It also maintained lipid profile and tests of liver and kidney functions within normal range as compared to diabetic control rats and almost at par with standard drug metformin. The oxidative stress induced decline in glutathione and catalase in liver and kidney tissues showed recovery nearly to normal level as a function of treatment. The GC–MS profile of the extract showed relatively high concentration of β-sitosterol which was characterized by different spectroscopic and chromatographic techniques. The result scientifically and comprehensively validate the reported use of roots of this indigenous plant against diabetes. A strong antioxidant activity of the ethanolic root extract suitably compliments the antidiabetic effect.  相似文献   
550.
This essay examines how the increasing dependence of the academy, specifically communication studies, on corporate and federal funding is creating a sector of embedded intellectuals. Using the theoretical lens of what is loosely called “autonomism,” I argue that the concept of General Intellect forces us to reconsider traditional notions of intellectual work. The significance of communication, as both a growing academic field and infrastructure for this General Intellect, puts the discipline in the spotlight. After summarizing Gramscian and Foucauldian conceptions of the engaged intellectual, I sketch out a figure of the intellectual adequate to these conditions, what I call the machinic intellectual.  相似文献   
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