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191.
We present the mathematical model and an artificial neural network method for calculating the buckling load of a beam column with different end conditions. A trial solution of the beam column equation is written as a sum of two parts, in which first part satisfies the boundary conditions and the second part represents the feed forward neural network containing adjustable parameters, weights and biases. We prepared the Error function by using the beam column equation and its boundary conditions, which is used in the back propagation method with deflection term to update the network parameters. It is found that the artificial neural network method is capable for calculating deflection of a beam column as a part of the training process. To ascertain the soundness, efficiency and accuracy of the proposed method the results are compared to the Euler critical load.  相似文献   
192.
Low serum vitamin D level has an increased association with risk of multiple sclerosis (MS).There has been no published data on the levels of this vitamin in Indian population with MS. Hence we decided to undertake this study to document if there is evidence of vitamin D deficiency in patients with MS in our population. 26 patients with diagnosis of MS by modified Mc Donald’s criteria were enrolled in this study. Serum vitamin D (1,25 hydroxy) levels were measured by electro-chemiluminescence in our biochemistry lab. An age-matched control group of 202 patients who did not have a diagnosis of MS were included. In our study group 76.9 % had vitamin D level less than 20 ng/ml compared to 65.5 % of control group (p value of 0.019). Our study revealed a trend towards low vitamin D values in Indian MS patients.  相似文献   
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This paper explores the ideology of social justice through links between equality and equity within Early Years and what remain the challenges for leadership. Questionnaires and interviews in English multi-cultural and mono-cultural schools with Early Years age phases were conducted. The findings showed that the ideology of social justice, equality and equity was interpreted differently in each Early Years setting. The multi-cultural schools used a variety of activities to embed social justice principles that involved their diverse communities more to enrich the curriculum in contrast to the mono-cultural schools. In mono-cultural schools however, leadership had to be more creative in promoting equality and equity, given the smaller proportion of their diverse pupil and staff population. Our conclusions suggest that most schools are struggling initially with implementing the current changes in Early Years, therefore their vision for permeating this curriculum with an equality and equity focus is at the early stages.  相似文献   
196.
N. Kumar 《Resonance》2013,18(5):458-467
In this section of Resonance, we invite readers to pose questions likely to be raised in a classroom situation. We may suggest strategies for dealing with them, or invite responses, or both. “Classroom” is equally a forum for raising broader issues and sharing personal experiences and viewpoints on matters related to teaching and learning science.  相似文献   
197.
Oxidative stress has been found to play important role in several neuropsychiatric diseases including Obsessive Compulsive Disorder. A longitudinal case control study was conducted to evaluate the oxidative stress in 30 newly diagnosed obsessive compulsive disorder patients and same number of control patients. Serum thiobarbituric acid reacting substances, plasma ascorbate were assessed to evaluate oxidative stress and Yale Brown obsessive compulsive scale for disease severity before and after treatment with Fluoxetine at the average dosage of 40 mg/day. Improvement in Yale Brown obsessive compulsive scale score by about 43% after 12 weeks treatment was associated with significantly decreased thiobarbituric acid reacting substances and increased plasma ascorbate values (p < 0.05). The newly diagnosed obsessive compulsive disorder patients had higher serum thiobarbituric acid reacting substances as well as a lower plasma ascorbate levels than the control population. Thus, the present study suggested a significant role of oxidative stress in obsessive compulsive disorder and showed that a successful treatment with Fluoxetine not only improves the clinical scenario but also reduces the oxidative stress that may further improve the prognosis of the disease.  相似文献   
198.
Aflatoxins are potent hepatotoxic and hepatocarcinogenic agents. Reactive oxygen species and consequent peroxidative damage caused by aflatoxin are considered to be the main mechanisms leading to hepatotoxicity. The present investigation aims at assessing the hepatoprotective effect of ethanolic leaves extract of Trianthema portulacastrum on aflatoxin B1 (AFB1)-induced hepatotoxicity in a rat model. The hepatoprotection of T. portulacastrum is compared with silymarin, a well known standard hepatoprotectant. Lactate dehydrogenase, alkaline phosphatase, alanine and aspartate aminotransferases were found to be significantly increased in the serum and decreased in the liver of AFB1 administered (1 mg/kg bw, orally) rats, suggesting hepatic damage. Marked increase in the lipid peroxide levels and a concomitant decrease in the enzymic (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glucose-6-phosphate dehydrogenase and glutathione-S-transferase) and nonenzymic (reduced glutathione, vitamin C and vitamin E) antioxidants in the hepatic tissue were observed in AFB1 administered rats. Pretreatment with T. portulacastrum (100 mg/kg/p.o) and silymarin (100 mg/kg /p.o) for 7 days reverted the condition to near normal. The results of this study indicate that the ethanolic leaves extract of T. portulacastrum is a potent hepatoprotectant as silymarin.  相似文献   
199.
The aim of the study was to ascertain the role of ethanolic extract of Cynodon dactylon against hepatic complications in streptozotocin (STZ) induced type 2 diabetic models. Effect of the pre identified most effective dose of 500 mg/kg body weight was studied on hepatic injury caused by chemically induced diabetes by 55 mg/kg body weight i.p. injection of STZ in male Wistar rats. The dose of 500mg/kg body weight given once daily for 14 days reduced the levels of serum glutamate oxaloacetate transaminase, serum glutamate pyruvate transaminase, alkaline phosphatase, creatinine and urine sugar significantly (P<0.05) with increase in total protein, haemoglobin and body weight was increased. High LD50 validates its high margin of safety.  相似文献   
200.
The present study defines the systematic evaluation and the role of minerals in glycemic potential of aqueous extract of Withania coagulans fruits in order to develop an effective and safe alternative treatment for diabetes mellitus. Laser Induced Breakdown Spectroscopy was used for glycemic element detection. The study is based on the results of lowering in blood glucose levels of normal, sub, mild and severely diabetic rats assessed during fasting blood glucose, glucose tolerance test and post prandial glucose studies. The dose of 1000mg/ kg was identified as the most effective dose, which reduces the Fasting Blood Glucose level maximum by 33.2% at 4h in normal rats during fasting blood glucose studies. Glucose tolerance test studies of normal, sub and mild diabetic rats showed the maximum reduction of 15.7, 28.9 and 37.8% at 3h respectively. Long-term study in case of severely diabetic rats showed reduction of 52.9 and 54.1% in Fasting Blood Glucose and Post Prandial Glucose levels respectively after 30 days of treatment. The present study, besides confirming hypoglycemic and antidiabetic activities of aqueous extract of W. coagulans, helps in identifying the role of trace minerals like Mg & Ca responsible for antidiabetic potential of this potent indigenous shrub.  相似文献   
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