Physicochemical characteristics of various milk samples available in Pakistan

We report physicochemical characteristics of various kinds of liquid milk commercially available in Pakistan in comparison with those of fresh natural milk from animals. Milk samples were collected from local markets at Peshawar, Pakistan,and analyzed for their physical features, including moisture, total solids, specific gravity, conductivity, viscosity and titratable acidity (lactic acid equivalent), and chemical components and macro-minerals, including total protein, casein, lactose, ash and minerals (Na, K and Mg). These items were compared with the physicochemical characteristics of the fresh natural milk samples from buffalo, cow and goat. The results were also compared with reported nutritional quality of milk from various countries and World Health Organization (WHO) standards. We found that all the physical features and chemical components of commercially available milk in Pakistan markets meet WHO's requirements, except for Na, K, Ca and Mg, which are below the standards.     

苏联高等学校的教学原则

苏联高等学校教育学的任务在于:为了适应社会主义国家的要求在考虑科学、技术最新成就的基础上制定出高等学校里教学与教育工作的最有效的方法、方式和手段。高等学校教研室的教学与教学法工作是建立在各门课程的一定教学规律性的基础上,建立在高等学校的教学、教育原则的基础上的。高等学校的教师应该是本行科学知识领域里的专家,同时应该也是清楚了解高等学校教育学里的统一教学原则和善于运用这些原则的人。     

教育与经济增长

本文首先回顾了近年来关于经济增长影响因素的文献,特别探讨了教育在其中的作用。然后,估计了一个关于增长的综合模型,并就其稳健性进行了跨国检验。最后,据此得出了政策性建议。     

如何为孩子制定有效的行为准则——推荐《做称职的父母》

这是一本教您怎样才能尽到父母应尽的责任的书,本刊摘编其中一章,希望通过讲述如何为孩子制定行为准则的观点,在家教实践方面给予您一定的启示。     

“亲爱的读者”和“无聊的作者”——乔伊斯在《为芬尼根守灵》中对读者的直呼

自中世纪以来没有一部重要文学作品象乔伊斯的《为芬尼根守灵》(以下简称《守灵》译者注)那样令读者望而却步.意识到理解该书文本的难度,乔伊斯希望并真诚期待苦于理想失眠症的理想读者愿意拿出足够的时间来欣赏本书关大脑在夜间的活动情况(正如《尤里西斯》把注意力放在白大的意识流上一样).与十八世纪小说家如出一辙,乔伊斯在《守灵》中频频直呼其读者——建议、哄骗、嘲弄这些忙忙碌碌的失眠者.这是该书获得较少注意的重要方面.从整体上看,乔伊斯与读者的对话象是一本有趣的善意的阅读指南,对《守     

Effects of medium composition on the production of plasmid DNA vector potentially for human gene therapy

INTRODUCTION The difficulties associated with large-scaleproduction of biotherapeutics provide a constantchallenge to the biotechnology industry. FDA hadadded “therapeutic DNA plasmid vectors” to the listof well-characterized biotechnology product (DoHHs,1996), and gene therapy has moved rapidly fromlaboratory scale to clinical trials. It is urgent to de-velop new protocols to obtain high-quality plasmidswith high yields and minimal or no contamination ofRNA and chromosomal D…     

Do the effects of computer-assisted practice differ for children with reading disabilities with and without IQ-achievement discrepancy?

This study was designed to assess whether the effects of computer-assisted practice on visual word recognition differed for children with reading disabilities (RD) with or without aptitude-achievement discrepancy. A sample of 73 Spanish children with low reading performance was selected using the discrepancy method, based on a standard score comparison (i.e., the difference between IQ and achievement standard scores). The sample was classified into three groups: (1) a group of 14 children with dyslexia (age M = 103.85 months; SD = 8.45) who received computer-based reading practice; (2) a group of 31 "garden-variety" (GV) poor readers (age M = 107.06 months; SD = 6.75) who received the same type of instruction; and (3) a group of 28 children with low reading performance (age M = 103.33 months; SD = 9.04) who did not receive computer-assisted practice. Children were pre- and posttested in word recognition, reading comprehension, phonological awareness, and visual and phonological tasks. The results indicated that both computer-assisted intervention groups showed improved word recognition compared to the control group. Nevertheless, children with dyslexia had more difficulties than GV poor readers during computer-based word reading under conditions that required extensive phonological computation, because their performance was more affected by low-frequency words and long words. In conclusion, we did not find empirical evidence in favor of the IQ-achievement discrepancy definition of reading disability, because IQ did not differentially predict treatment outcomes.     

键级和化合价的分子轨道理论

本文译自美国《Journal of chemical Education》1988年第8期.作者简介了密立根布居数分析法,并以此为基础讨论了键级和化合价,应用了别致的原子轨道线性组合分子轨道理论(LCAO—MO)的矩阵公式.最后给出了一些简单分子的计算结果,以说明这个理论的应用.     

史努比

~~史努比@查尔斯·M·舒尔茨(charles M.Schulz)