Synthesis of RC transfer immittance functions with a minimum number of capacitors

In this paper a method for the realization of RC transfer immittance functions with an unsymmetrical lattice is presented. The method yields minimal capacitor realizations for Z₁₂(s) with no pole at s = 0 and ?y₁₂(s) having no pole at s = ∞. The number of resistors needed are only two more than the minimum needed.     

Induction of diabetes by Streptozotocin in rats

The objective of this study is to induce experimental diabetes mellitus by Streptozotocin in normal adult Wistar rats via comparison of changes in body weight, consumption of food and water, volume of urine and levels of glucose, insulin and C-peptide in serum, between normal and diabetic rats. Intra-venous injection of 60mg/kg dose of Streptozotocin in adult wistar rats, makes pancreas swell and at last causes degeneration in Langerhans islet beta cells and induces experimental diabetes mellitus in the 2–4 days. Induction of experimental diabetes mellitus is indeed the first step in the plan of purification of pancreatic Langerhans islet cells of normal rats for transplanting under the testis subcutaneous of experimentally induced diabetic rats. Streptozotocin induces one type of diabetes which is similar to diabetes mellitus with non-ketosis hyperglycemia in some animal species. For induction of experimental diabetes in male adult rats weighted 250–300 grams (75–90 days), 60mg/kg of Streptozotocin was injected intravenously. Three days after degeneration of beta cells, diabetes was induced in all animals. The diabetic and normal animals were kept in the metabolic cages separately and their body weight, consumption of food and water, urine volume, the levels of serum glucose, insulin and C-peptide quantities in all animals were measured and then these quantities were compared. For a microscopic study of degeneration of Langerhans islet beta cells of diabetic rats, sampling from pancreas tissue of diabetic and normal rats, staining and comparison between them, were done. Induction of diabetes with Streptozotocin decreases Nicotinamide-adenine dinucleotide (NAD) in pancreas islet beta cells and causes histopathological effects in beta cells which probably intermediates induction of diabetes. In this study, we used Streptozotocin for our experiments in induction of experimental diabetes mellitus. After Induction of diabetes, consumption of food and water, volume of urine and glucose increased in the diabetic animals in comparison with normal animals, but the weight of body and the volume of insulin and C-peptide decreased in the diabetic animals. Sampling and staining of pancreas tissue of diabetic and normal rats showed that the Langerhans islet beta cells of diabetic rats have been clearly degenerated. In three days, Streptozotocin makes pancreas swell and at last causes degeneration in Langerhans islet beta cells and induces experimental diabetes. It also changes normal metabolism in diabetic rats in comparison with normal rats. Consumption of water and food, volume of urine, serum glucose increases in diabetic animals in comparison with normal rats but the levels of serum insulin, C-peptide and body weight decreases.     

科技期刊审稿专家的评价和改进措施

【目的】通过对审稿专家的评价进而提出优化审稿专家的措施。【方法】 选取《中华微生物学和免疫学杂志》2011—2015年267位审稿专家7756条审稿记录,统计267位专家的审稿数量、审稿时滞及审稿结论。【结果】 通过统计和分析,5年间审稿篇次>31篇的66位专家是期刊的核心审稿专家,其中,审稿时滞在3周以内的专家占92.5%;审稿时滞上,就所有专家而言,74.2%的能在3周内审回稿件;审稿结论上,拒审占5.0%,无具体审稿意见或审稿意见过简无针对性的占10.5%。【结论】 要保证期刊的核心专家队伍,必须从专家和编辑两个层面进行改进。对专家适当取舍,保证核心审稿专家的数量;同时编辑应做好服务工作,重视专家的知识回报。     

变化环境中的城市健康与福祉——系统的分析视角

随着城市人口的不断增加,城市环境的不断变化,城市健康与福祉问题已经得到了国际社会高度关注。在城市环境中,各种复杂的影响因素及各因素之间的反馈机制都会影响居民的健康与福祉。城市健康问题的解决,不仅需要科学家的研究,还需要政策制定者以及所有利益相关方的共同参与。文章结合中国城镇化现状和城市的健康问题,介绍国际科联城市健康与福祉研究计划,并将系统研究城市健康的方法应用到中国新型城镇化战略中。     

非人灵长类模型

全球有近10亿脑疾病患者,每年约带来经济负担1万亿美元。目前,绝大部分脑疾病尚无有效治疗方法。因此,脑疾病机理研究和新药开发十分迫切。由于进化上相近,非人灵长类的脑在结构、功能活动等多方面与人类高度相似。因此,相对于其他实验动物,非人灵长类具有解决人类问题,特别是脑相关问题的独特优势。它们除了是研究人类正常脑高级功能的关键实验动物外,还是最好的研究脑疾病机理和治疗方法的模型动物。中国不但有丰富的非人灵长类资源,而且在猕猴建模方面有很好的积累,尤其在转基因疾病猕猴模型创建方面,目前处于世界领先的地位。文章分析了脑疾病领域的国家战略需求,总结了国内外非人灵长类的应用情况,以及国内非人灵长类模型现状。在此基础上,对我国非人灵长类模型领域下一步发展的重点提出了建议。     

中国科学院在我国纳米科技研究中的作用与地位分析

本文结合我国、中国科学院纳米科技研究的发展历程,从研究项目的组织与实施、研究资源的优化与整合及研究成果的获得与影响等各方面对中科院在我国纳米科技研究中的作用与地位进行了分析,同时提出了中科院乃至我国在纳米科技研究领域中存在的问题与建议,希望能对我国未来纳米科技发展有所裨益。     

Mathematical methods for modelling price fluctuations of financial times series

Statistical and Fourier analysis methods of time series representing fluctuations of stock market in general and Indian stock markets in particular are well known. This work is motivated by a recent paper by Guharay [Operations Research and Financial Engineering, Princeton University, Princeton, NJ, preprint, 2002] where he has studied trends in the S & P 500 for various time periods using wavelet tools. Our paper deals with a few Indian and Saudi stock prices and return fluctuation for a certain period of time. The main objective of the analysis is to understand the dynamics of the Indian and Saudi stock markets. We look for similarities, point of abrupt changes, normalized data, return, volatility, graph, pure and noise part, correlation lengths, and signal-to-noise ratio.     

A biochemical study on the effect of Riboflavin on cataractous rat lenses. II Proteins and Glutathione

Proteins and glutathione (GSH) levels were estimated in the experimental groups. Levels of both proteins and glutathione in the control and the treated groups were found to be significantly decreased compared to the normal group. The results show that supplementation of riboflavin has beneficial effect by alleviating the oxidant injuries to GSH and proteins, which are involved in the maintenance of transparency and protection of thiol groups of the lens. Thus, riboflavin has an active role in the lens metabolism and has a potential to improve the metabolic activity of the cataractous lenses.     

Raised serum homocysteine levels in patients of coronary artery disease and the effect of vitamin B12 and folate on its concentration

Homocysteine(Hcy) has been implicated as a novel risk factor of Coronary Artery Disease (CAD) among Asian Indians, but many studies done in India failed to reveal any direct correlation. It has also been reported that Folic acid and Vitamin B12 levels inversely affect serum levels of homocysteine. In this study, we looked at the levels of homocysteine among patients with CAD. The effect of Vitamin B12, Folate and other risk factors on homocysteine levels were also evaluated. Mean homocysteine levels in cases (22.81±13.9, n=70) were significantly higher (p=<0.001) than the controls (7.77±7.3, n=70). However no statistically significant correlation could be deduced between homocysteine Vitamin B12, and Folate. Cumulative analysis have indicated an increase in homocysteine levels among patients with CAD with every additional risk factor.     

提取方正排版文件广义元数据并生成全文HTML的探索

【目的】实现自动提取科技期刊全文元数据并生成HTML文件。【方法】 以方正排版文件为对象,在可以提取出来文章的标题、摘要等元数据的基础上,将文章的正文内容元数据化,提出了包含图、表、公式等的广义元数据概念,并建立了提取图、表元数据的提取规则,同时将方正排版数学公式转化为LaTeX表达式。然后利用VB编程软件编写了自动提取广义元数据程序并将元数据重新组合生成HTML格式的文件。【结果】 根据方正BD排版语言的特点,建立的提取规则能有效提取全文并元数据化,最后可直接生成HTML文件。【结论】 实际应用表明了利用广义元数据生成HTML文件的有效性和可行性。