联吡咯构象异构的理论计算

构象分析是阐明分子结构的最重要手段之一,理论计算能够给出分子构象异构的一般信息。采用HF/6-31G*、B3LYP/6-31G*、BHHLYP/6-31G*和MP2/6-31G*方法,对3种联吡咯构造异构体进行了构象分析。采用BHHLYP/6-31++G**方法进行势能面上稳定点和过渡态的计算。结果表明,气相中6个联吡咯能量极小构象体能量差最大达14.56kJ/mol,转化能垒最大达10.19kJ/mol。采用自洽反应场极化连续模型溶剂理论,探讨了水溶剂对优势构象异构体的几何结构和能量的影响。结果表明,水相中6个联吡咯能量极小构象体的能量差最大达9.40kJ/mol,转化能垒最大达11.68kJ/mol。这种系统化研究有助于理解联吡咯各构造异构体之间构象能量与几何结构的关系。     

乌兰察布地区胡萝卜品种比较试验及最佳种植密度初探

通过对乌兰察布地区4个主栽胡萝卜品种比较试验和栽培密度进行研究,结果表明,千红百日品种具有较好的肉质根性状和较高的产量及较好的适口性,可以作为目前该地区较为理想的首选品种,有推广价值;种植密度对胡萝卜产量、肉质根性状影响很大,综合评判,胡萝卜适宜种植密度约为保苗3万株/667m2左右。     

三江源地区植被盖度与居民点的关系研究

本文基于人口与环境相关联的地理视角,运用最大化合成法、缓冲区分析法,研究三江源地区植被分布与人口、居民点的关系。研究表明:①从大的空间尺度看,居民点主要分布在NDVI条件好的区域;NDVI条件差的区域,居民点分布较少;②在几十公里距离范围内,植被盖度与离居民点的距离的关系是:居民点密度大的地区,随着距居民点距离的增加NDVI呈上升趋势;居民点密度居中的地区,随着距居民点距离的增加NDVI呈下降趋势;居民点密度小的地区,NDVI与距离居民点远近没有明显相关关系;③对典型牧业居民点小尺度范围内人口分布与NDVI关系的研究发现,距居民点2km范围内,由于人类的放牧活动造成了植被的退化,NDVI较低;2～4km范围内,植被受人类放牧活动影响越来越小,随着距离的增加NDVI呈显著上升态势;4～10km范围内,因为自然条件的差异,NDVI随着距离的增加逐渐变小;④在1998年-2009年即三江源生态治理工程期间,NDVI总体上是上升的。     

Association of Estrogen Receptor-α Gene &; Metallothionein-1 Gene Polymorphisms in Type 2 Diabetic Women of Andhra Pradesh

Type 2 diabetes mellitus (DM) is a multifactorial disease where both genetic and environmental factors contribute to its pathogenesis. Estrogen plays an important role in type 2 DM pathogenesis. A number of polymorphisms have been reported in the estrogen receptor (ESR1), including the XbaI and PvuII restriction enzyme polymorphisms of ESR1,which may be involved in disease pathogenesis. Metallothioneins (MT) act as potent antioxidants against various oxidative damages. Very few studies have indicated the association between Estrogen Receptor-α, MT1 gene polymorphisms with type2 DM. A total of 100 type 2 diabetic women and 100 age, sex matched controls were recruited. Using the PCR based RFLP method, the PvuII and XbaI polymorphisms of ESR1 and in MT1A (rs8052394 and rs11076161) gene polymorphisms were analysed. The genotype distribution and frequency of mutated allele showed no significant differences between diabetic and non-diabetic groups in PvuII (χ2 = 2.443; P = 0.1181) or XbaI (χ2 = 1.789; P = 0.1812) and rs8052394 (χ2 = 1.154; P = 0.2840) or rs11076161 (χ2 = 0.4141; P = 0.5199), polymorphisms. This is the first Indian study to conclude that ESR1 and MT1 gene polymorphisms are not associated with increased susceptibility to type 2 diabetes in Indian women.     

Seeing epistemic order: construction and transmission of evaluative criteria

This paper focuses on formative assessment in the field of higher education. It examines Bernstein’s work on vertical discourses and knowledge structures with the view to deepening understanding of the concept of assessment for learning. The first part of the paper draws on Vygotsky’s work on concept development and Bernstein’s work on knowledge structures to explain why ‘generalisation’ and ‘hierarchy’ are central in knowledge acquisition. It then explores Bernstein’s claim that, within the vertical discourse, different knowledge structures (hierarchical and horizontal) afford greater or lesser visibility of their epistemic structure, and thus of their evaluation criteria of what counts as a legitimate text. The second part of the paper investigates the ways epistemic expectations are signalled through the practice of evaluation to first‐year university students in a professional education course and proposes that markers do not offer students stuffiest access to recognition rules necessary for producing legitimate texts in the future. Drawing on Maton’s distinction between semantic gravity and semantic density, the paper offers an example of how markers could recast what is present in students’ work to offer students access to key ordering principles in vertical discourses.     

健身气功对绝经女性骨密度和骨代谢影响研究

探讨四种健身气功锻炼对绝经女性骨密度和骨代谢指标的影响。将60名绝经女性,随机分为非体育锻炼对照组和健身气功易筋经、五禽戏、八段锦和六字诀等4个运动组,经12个月的健身气功练习后分别测试骨密度（BMD）,血清钙（Ca）、磷（P）、碱性磷酸酶（ALP）、尿脱氧吡啶啉排泄率（DPD/Cr）的比例。结果表明,对照组骨量丢失,骨密度下降,4个健身气功组的骨密度均增加,并且与实验前相比具有显著性差异;4个健身气功组碱性磷酸酶（ALP）与对照组相比明显升高,而尿脱氧吡啶啉排泄率（DPD/Cr）明显低于对照组。结论：四种健身气功锻炼对绝经女性骨密度的影响是积极的,能促进骨密度增大,改善骨代谢。     

儿童青少年抗阻练习研究

儿童和青少年进行抗阻练习能提高肌肉力量、增强骨骼密度、减少受伤几率和改善心理状况。但儿童青少年的身体和心理都还不够成熟,练习中容易出现风险。为规避风险,不仅需注重指导,还需注重准备活动、练习器材、练习强度与运动量。     

运动和骨质疏松的早期预防

骨质疏松是老年人常见疾病,轻微外伤易导致骨折发生,其并发症可危及生命.但长久以来,不被人们所重视.由于目前缺乏安全有效的根治方法,因此正确的认识、早期预防骨质疏松显得尤为重要.作者在对运动提高骨密度的研究进行综述的基础上,提出了预防骨质疏松要从小抓起,要科学合理地安排运动.     

运动和补钙对成年女性骨密度的影响

分析运动和补钙对年龄在20~59岁的成年女性骨密度的影响。方法:随机抽取浦东新区2400名成年女性,采用问卷调查了解受试者的生活方式,根据生活方式(运动、补钙)的不同进行分组,然后对不同组别的受试者进行超声骨密度衰减值测试。结果显示:20~29、30~39、50~59岁组的Ⅲ组、Ⅳ组骨密度显著高于Ⅰ组、Ⅱ组(P<0.05);30~39、40~49、50~59岁组Ⅱ组比Ⅰ组的骨密度高,但无显著性差异(P>0.05);30~39岁组的Ⅲ组、Ⅳ组骨密度显著高于Ⅰ组、Ⅱ组(P<0.01);20~29岁组的Ⅰ组骨密度比Ⅱ组高0.5dB/MHz,但无显著性差异(P>0.05)。结论:成年女性的骨密度与其是否长期坚持体育运动关系密切,而服用钙制剂和喝牛奶等补钙方法不是决定骨密度的直接因素。     

InP电子结构和介电函数的第一性原理计算

计算了InP电子结构和介电函数,从理论上给出了电子结构和介电函数的关系.所有计算都是基于密度泛函理论框架下的第一性原理平面波超软赝势方法.利用精确计算的能带结构和态密度分析了带间跃迁占主导地位的InP材料的介电函数,为InP材料的设计与应用提供了理论依据.