矿业工程领域工程硕士实效性课程教学模式探讨     

丁德馨  杨月平  杨仕教 《中国地质教育》2010,19(3):32-35

矿业工程领域工程硕士研究生大多来自矿山企业的管理岗位和技术岗位,存在着工、学冲突的问题。针对这些特点,我们提出采用模拟学术会议教学、准实地教学和远程学导式教学模式,以提高工程硕士研究生课程教学的实效性。  相似文献   

长春市大学女生体成分与骨密度的调查研究   总被引：1，自引：0，他引：1  

刘娜 《吉林体育学院学报》2010,26(3):81-82

研究长春市大学女生的身体成分和骨量水平,探讨骨密度的影响因素。方法：应用双能X线骨密度测定仪和体成分分析仪对长春市251名大学女生的体成分、腰椎、股骨颈和Ward’S区的骨密度进行测定。结果：相关分析显示总体重、BMI、瘦体重及体脂百分比均与骨密度呈显著正相关,相关性大小排序为：总体重〉BMI〉体脂百分比〉瘦体重;经常运动女生的腰椎、股骨颈及Ward’S区骨密度与较少运动者有显著性差异。结论：总体重可能影响女性骨骼健康;体育运动可促进形成较高的峰值骨密度,预防骨质疏松。  相似文献   

青春期女性骨量峰值影响因素研究   总被引：1，自引：0，他引：1  

扈婧 《衡水学院学报》2009,11(1)

女性最快速的骨量获得发生在青春早期至青春中期,青春晚期开始减退,青春期女性骨量峰值的高低与非生物力学因素和生物力学因素有关.非生物力学因素包括遗传、性别、钙的摄入、光照,烟酒嗜好等,生物力学因素是适量的运动,不同的运动方式,运动强度或持续时间不同对骨骼所起的作用也不一样.合理的体育运动可使青春期女性在生长期获得尽可能高的基础骨量,对提高其骨量峰值、预防骨量丢失和骨质疏松均具有非常重要的作用.  相似文献   

Time course of recovery of vertical jump height and heart rate versus running speed after a 90-km foot race     

Alan M Nevill  Roger L Holder  Arthur D Stewart 《Journal of sports sciences》2013,31(7):645-650

It is well known that sport and exercise play an important role in stimulating site-specific bone mineral density (BMD). However, what is less well understood is how these benefits dissipate throughout the body. Hence, the aim of the present study was to compare the BMD (recorded at nine sites throughout the skeleton) of 106 male athletes (from nine sports) with that of 15 male non-exercising age-matched controls. Given that BMD is known to increase with body mass and peak with age, multivariate and univariate analyses of covariance were performed to compare the BMD of the nine sports groups with controls (at all sites) using body mass and age as covariates. Our results confirmed a greater adjusted BMD in the arms of the upper-body athletes, the right arm of racket players and the legs of runners (compared with controls), supporting the site-specific nature (i.e. specific to the externally loaded site) of the bone remodelling response (all P?<0.01). However, evidence that bone mass acquisition is not just site-specific comes from the results of the rugby players, strength athletes, triathletes and racket players. The rugby players' adjusted BMD was the greatest of all sports groups and greater than controls at all nine sites (all P?<0.01), with differences ranging from 8% greater in the left arm to 21% in the lumbar spine. Similarly, the strength athletes' adjusted BMD was superior to that of controls at all sites (P?<0.05) except the legs. The adjusted BMD of the triathletes was significantly greater than that of the controls in both the arms and the legs as well as the thoracic and lumbar spine. The racket players not only had significantly greater right arm BMD compared with the controls but also a greater BMD of the lumbar spine, the pelvis and legs. In contrast, the low-strain, low-impact activities of keep-fit, cycling and rowing failed to benefit BMD compared with the age-matched controls. These results suggest that sporting activities involving high impact, physical contact and/or rotational forces or strains are likely to convey significant benefits not only to the loaded sites, but also to other unloaded peripheral and axial sites throughout the skeleton.  相似文献   

基于能级模型的我国金属矿产资源评价     

刘金平  赵月 《资源科学》2013,35(5):977-982

针对我国金属矿产资源的开采利用量大、浪费严重和我国金属矿产资源评价模型研究匮乏等问题,本文首次提出金属矿产资源能级的概念——金属矿产资源为国民经济和社会发展提供商品或服务的能量大小.建立了基于金属矿产资源质量M、数量Q、重要程度I和技术条件T等4个指标的定量评价模型,对各指标进行细化、归一化并划分等级.以金属铁、铝、金、铜、钼、钨、锡为例的分析表明,其能级分别为1.748、1.015、1.65、1.353、2.419、2.953、2.025,能级模型可对我国所有的金属矿产资源进行能级测算和划分,从而针对不同能级的金属矿产资源采取不同的开采、管理措施,实现我国金属矿产资源的有效管理.  相似文献   

体力活动与骨骼、关节和肌肉健康          下载免费PDF全文

王晶晶 《体育科研》2011,32(1):44-50

长期规律的体力活动可预防骨质疏松性骨折,有利于改善脊柱和髋关节骨密度,增加肌肉总量、肌力和肌肉爆发力,且不会使无关节损伤史的人发生骨关节炎。而对于骨关节炎患者来说,中等强度、低冲击性的体力活动有利于改善症状和预后．总体而言。目前已有的绝大部分研究证实,体力活动对骨骼、关节和肌肉的健康具有积极影响。  相似文献   

Body composition of English Premier League soccer players: Influence of playing position,international status,and ethnicity     

Laura Sutton  Mark Scott  Joanne Wallace  Tom Reilly 《Journal of sports sciences》2013,31(10):1019-1026

Abstract

Body composition is a key consideration in the physical make-up of professional soccer players. The aims of the present study were to determine whether the body composition of professional soccer players varied according to playing position, international status or ethnicity, and to establish which variables best distinguished the soccer players from a reference group. Body composition was assessed using dual-energy X-ray absorptiometry in 64 male professional soccer players. Measured variables included bone mineral density and the relative amounts of lean and fat mass. Data were analysed using analysis of variance and stepwise discriminant function. The soccer players recorded better values than a reference group (n = 24) for all body composition compartments. Percent lean mass and bone mineral density were the variables best able to identify the soccer players (95.5% correctly classified). Differences in body composition were evident between goalkeepers and outfield players, but not between outfield playing positions. No differences were found on the basis of international status. The non-Caucasian players demonstrated significantly lower percent body fat (9.2 ± 2.0%) than the Caucasian players (10.7 ± 1.8%). It was concluded that body composition is important for elite soccer players, but that homogeneity between players at top professional clubs results in little variation between individuals.  相似文献   

有氧训练和力量训练对男性中老年体成分和骨密度的影响     

徐中华 《体育科技文献通报》2013,21(7):103-105

本研究旨在通过调研和身体素质测试的方法,比较长期从事有氧运动和两种方式结合锻炼的两种中老年人各种素质指标之间的差异,研究两种锻炼方式对中老年人身体素质的影响。通过问卷调查将社区50-60岁居民120人(均为男性)分为有氧锻炼组(60人),两者结合组(60人)。在锻炼前后各进行两次体质测试,比较各指标均值差异。研究结果:适量规律的力量训练和有氧锻炼可以提高中老年人的身体素质,对心肺功能有一定的正向作用。  相似文献   

调水调沙工程对黄河尾闾河道碎屑矿物组成特征的影响     

张党玉  孙志高  王伟 《滨州学院学报》2019,(2):67-73

碎屑矿物在判别沉积物来源以及沉积环境变化等方面具有重要意义。基于对2013年汛前与汛后采集的黄河尾闾河道表层沉积物样品的鉴定,探讨了调水调沙工程实施导致的水动力变化对碎屑矿物组成特征的影响。结果表明,汛前或汛后黄河尾闾河道表层沉积物中共鉴定出重矿物31种,轻矿物11种。尾闾河道沉积物整体以轻矿物为主,占比达99%以上。重矿物优势矿种共8种,分别为普通角闪石、绿帘石、褐铁矿、阳起石、水黑云母、石榴子石、榍石和碳酸盐,其中普通角闪石占比高达29.98%,是主要标志性重矿物;轻矿物优势矿种共3种,分别为石英、斜长石及钾长石,其中石英占比高达59.75%,是主要优势矿种,并可用于确定物源。比较而言,汛后8种重矿物含量之和比汛前增加3.7%,尤其是普通角闪石,其在汛后占比较汛前增加8.62%。与之不同,轻矿物含量在汛前与汛后差异不大,但沿程变化明显。研究发现,尽管调水调沙工程在改变尾闾河道水动力的同时并未使其轻矿物组分发生明显改变,但其导致的重矿物沉积分异却较为明显。  相似文献   

食用菌菌种保藏方法的研究     

刘胜贵  刘卫今 《怀化学院学报》1996,(5)

利用不同菌种保藏方法保存了29个食用菌菌株．结果表明：固体石蜡封口的斜面冰箱保藏法，对陈香菇［Lentinusedodes（Berk·Sing．］3个菌株外的其它26个菌株保藏4年后，全部存活良好，并保持其原有的生产性能．这一方法结合矿油保藏祛，可用于一般食用菌菌种的中长期保存．  相似文献