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991.
Suicidal and help‐seeking behaviors of students of color remain a significant problem on college campuses. Self‐reported suicidal experiences and help‐seeking behavior of diverse students are examined on the basis of results from a national survey of college student mental health. The results suggest significant differences in the expression of suicidal thoughts and behavior across racial and ethnic groups and different experiences in their referral for, and utilization of, professional help.  相似文献   
992.
In this text, which was originally delivered as a speech, I discuss the massive critique of teachers in the public discourse on education in Sweden over the last decade. I speak in defence of teachers, and since I am a teacher I speak in defence of myself. The critique of teachers, schooling, and teacher education has been so overbearing that a purely rational response is simply not possible. Therefore, my response is rhetorical in tone. In highlighting the passion of teaching, I lift something central for teachers, which is seldom or never taught about teaching in teacher education. Neither is the passion of teaching present in the public discourse on education. Passion, I argue in the article, is that which adds excess or an overflow of meaning that cannot be contained within the order of discourse and which therefore puts this discourse out of balance. Finally, I discuss a new balance beyond this order in the context of a classroom. In a concluding section, I highlight the struggle over borders which define who can speak and think in “good” order and who cannot.  相似文献   
993.
Serum adenosine deaminase (ADA), 5′ nucleotidase (5′NT) and malondialdehyde (MDA) were estimated in patients with acute infective hepatitis (AIH) along with the routine parameters of liver disease. Present study is done to evaluate these special parameters in patients with clinical history of AIH and to assess the utility of these parameters as diagnostic/ prognostic indices of liver function and to correlate special parameters with routine live function tests (LFT). ADA, 5′NT and MDA along with routine LFT was estimated in 25 patients with AIH and 25 samples from healthy voluntary blood donars served as the control group. Routine LFT was estimated by standard clinical chemistry procedures on dade behring analyser and ADA, 5′NT and MDA were estimated by berthlot reaction, fiske and subbarao method and thiobarbituric acid method respectively. Statistical analysis showed that serum ADA, 5′NT and MDA were significantly higher in patients as compared with the controls. There was a significant positive correlation between ADA and total bilirubin and MDA and total bilirubin. Hence we can conclude that these tests would be more sensitive to diagnose the patients with AIH and that the raised bilirubin levels could be looked upon, as a protective mechanism which the liver has evolved in order to combat oxidative stress.  相似文献   
994.
Serum total lipids (cholesterol and triglyceride), lipoproteins (VLDL, LDL and HDL) and Apolipoprotein-B levels of normal healthy individuals (n=25) and coronary artery disease patients (n=25) were estimated. The objective of the present study was to ascertain the role of apo-B in causation and inheritance of coronary artery disease. It was observed that on an average serum total cholesterol and triglyceride more than 200 mg/dl bring the individuals to a risk of coronary artery disease (CAD) irrespective of the age. CAD patients achieved this value at an early age (35–45 years). Similarly VLDL and LDL levels were found to be significantly raised in CAD patients when compared to that of age matched normal individuals, with patients achieving risk values at an early age. HDL levels were found to be significantly lower in CAD patients as compared to normal individuals. Serum apo-B levels were significantly raised in CAD patients as compared to age matched normal individuals. Patients with positive family history of CAD had raised serum apo-B levels than those having negative family history. A positive coefficient of correlation was observed between serum apo-B and LDL levels suggesting that more the number of Apo-B particles, more will be the synthesis of atherogenic particle (LDL). Patients with negative family history had serum apo-B levels closer to those of normal individuals and in these individuals HDL levels were found to be significantly lowered, suggesting that loss of scavenger role of HDL could be the risk factor responsible for the causation of CAD in these patients, with negative family history of coronary artery disease.  相似文献   
995.
S. Negassi 《Research Policy》2004,33(3):365-384
The scope of this paper is to report new empirical evidence on the determinants of R&D co-operation. Indeed, the literature on the capabilities of firms emphasises the role of knowledge in the performance and evolution of firms who use knowledge developed in others to build their own knowledge capital. R&D co-operation between firms is one of the many strategies by which this knowledge may be transmitted. Several theoretical models have stressed that R&D co-operation is more likely when the level of spillovers is high. While this supposition is used in many theoretical models, it has rarely been tested before. Our results do not lend strong support to this intuition. Indeed, our spillover variables (national pure spillovers, national rent spillovers and imports of machine tools), which were supposed to match the theoretical notion of spillovers used in these theoretical models have a positive but not a significant role when explaining R&D co-operation. The R&D co-operation increases with size and with R&D intensity, but not with market share. It also increases with the budget spent on paying license fees and on acquiring patents and labour from foreign firms. In this study, we also analyse the determinants of innovation. In more precise terms, we compare the effects of R&D co-operation to those played by traditional internal factors and those exerted by external, pure and rent spillovers on the innovation capacity of the firms. Our results show that the commercial success of innovations of French firms depends mainly on size, market share, R&D intensity and human capital. Inward FDI from industrialised countries exerts a positive and significant effect. The finding highlights the important role of the absorptive capacity of firms. Spillover measurements, such as the acquisition of machine tools, foreign patents, licenses, and technological opportunities have a positive impact on innovation.  相似文献   
996.
In this paper, the problem of stability analysis for neural networks with time-varying delays is considered. By the use of a newly augmented Lyapunov functional and some novel techniques, sufficient conditions to guarantee the asymptotic stability of the concerned networks are established in terms of linear matrix inequalities (LMIs). Three numerical examples are given to show the improved stability region of the proposed works.  相似文献   
997.
998.
To study the mechanism of action of water soluble compound GII purified from fenugreek (Trigonella foenum graecum) seeds which was shown earlier to have antidiabetic effect in the subdiabetic, moderately and severely diabetic rabbits. In rabbits (1–1.5 kg bw) diabetes was induced by intravenous injection of 80 mg/kg bw of alloxan. They were fed with GII at a dose of 50 mg/kg bw daily once in the morning for 15 days in the subdiabetic and moderately diabetic and 30 days in the severely diabetic rabbits. Serum total cholesterol (TC), triglycerides (TG), LDL + VLDL cholesterol [(LDL + VLDL)C], HDL cholesterol [(HDL)C], total tissue lipids, glycogen and enzymes of carbohydrate metabolism (glycolysis, gluconeogenesis, polyol pathway) hexokinase, glucokinase, pyruvate kinase, malic enzyme, glucose-6-phosphatase, glucose-6-phosphate dehydrogenase, aldose reductase and sorbitol dehydrogenase and antioxidant enzymes glutathione peroxidase, glutathione reductase and superoxide dismutase were estimated. Liver and kidney function parameters were also estimated. Treatment with GII for 15 days in the subdiabetic and moderately diabetic rabbits and for 30 days in the severely diabetic rabbits (i) decreased the elevated lipids TC, TG, (LDL + VLDL)C and increased the decreased (HDL)C, (ii) decreased the elevated liver and heart total lipids, TC and TG, (iii) increased the decreased liver and muscle glycogen, (iv) increased the decreased hexokinase, glucokinase, pyruvate kinase, malic enzyme, glucose-6-phosphate dehydrogenase, superoxide dismutase, glutathione peroxidase, (v) decreased the increased glucose-6-phosphatase, sorbitol dehydrogenase, aldose reductase. Results thus show that treatment with GII compound purified from fenugreek seeds for 15 days in the subdiabetic and moderately diabetic and 30 days in the severely diabetic rabbits corrects the altered serum lipids, tissue lipids, glycogen, enzymes of glycolysis, gluconeogenesis, glycogen metabolism, polyol pathway and antioxidant enzymes. Histopathological abnormalities (fatty infiltration and other cellular changes) seen in the pancreas, liver, heart and kidneys were repaired after treatment with GII. In fact partially damaged pancreas was repaired. Liver and kidney function test results were normal in the GII treated animals indicating that GII treatment is safe and free from any side effects.  相似文献   
999.
The dynamics of the impact and coalescence of droplets on a solid surface   总被引:1,自引:0,他引:1  
A simple experimental setup to study the impact and coalescence of deposited droplets is described. Droplet impact and coalescence have been investigated by high-speed particle image velocimetry. Velocity fields near the liquid-substrate interface have been observed for the impact and coalescence of 2.4 mm diameter droplets of glycerol∕water striking a flat transparent substrate in air. The experimental arrangement images the internal flow in the droplets from below the substrate with a high-speed camera and continuous laser illumination. Experimental results are in the form of digital images that are processed by particle image velocimetry and image processing algorithms to obtain velocity fields, droplet geometries, and contact line positions. Experimental results are compared with numerical simulations by the lattice Boltzmann method.  相似文献   
1000.
This paper discusses the controller synthesis problem of a nonlinear networked controlled system subject to delays in the measurement and actuation channels. The communication through the network also suffers non-stationary packet dropouts. The bounded nonlinearities in the plant state satisfy Lipschitz conditions. A Lyapunov function is developed for the closed-loop system considering dynamic output feedback and the resulting stabilization conditions are drawn in the form of linear matrix inequalities to ensure that the system is exponentially stable in the mean-square sense. The developed conditions are represented in the form of a convex optimization problem and the results are tested by simulation on a quadruple-tank process.  相似文献   
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