月季花色素对运动大鼠骨骼肌氧化应激损伤的影响

目的:观察补充月季花色素对运动性氧化应激损伤的影响并探讨其可能作用机制。方法:雄性SD大鼠40只随机分为安静对照组(CG)、运动组(EG0h、EG48h)、运动+补药组(ER0h、ER48h),每组8只。EG、ER组进行递增负荷跑台运动4周,ER组每天给予月季花色素1ml/100g体重灌胃。训练结束后按组别取材,测定血清CK、LDH的活性,肌组织中MDA、SOD的活性。结果:(1)EG组运动后血清CK、LDH活性均显著升高(P<0.05),运动后48h仍高于CG组(P<0.05);ER组运动后48h血清CK、LDH活性均明显低于EG组(P<0.05)。(2)EG组运动后肌组织中MDA的含量明显升高(P<0.05),SOD的活性显著降低(P<0.05);ER组运动后即刻、48h肌组织中MDA的含量明显低于EG组(P<0.05),SOD活性均高于EG即刻、48h组(P<0.05)。结论:补充月季花色素可明显抑制运动肌组织中脂质过氧化反应,降低血清肌肉酶的活性,提示月季花色素对运动性氧化应激损伤具有一定的抑制作用。     

Changes in Myocardial Mass Associated with Age and Stress: Reexamination of Ventricular Hypertrophy

Abstract

Hearts from 126 male Sprague-Dawley rats (two age groups) were studied to determine effects of age, chronic hypoxia, and exercise on ventricular weight. Exercised rats had significantly heavier absolute total ventricular weights (right plus left) compared with chronically hypoxic or control rats. Whether expressed as absolute or percent total ventricular weight, chronically hypoxic rats had significantly larger right ventricles but significantly smaller left ventricles than exercised or control rats. Expressed as absolute weight, older rats (11 months) had significantly larger right or left ventricles than young rats (3 months). Expressed as percent total ventricular weight, young rats had left ventricles 4% smaller, but right ventricles 4% larger than older rats (p <.05). Type of work overload (volume or pressure) and functional location of workload (pulmonary or systemic) were suggested physiological mechanisms for stress- and age-related changes in myocardial mass.     

Description of a Low Cost Microcomputer System Interfaced to Exercise Stress Testing Equipment

Abstract

In recent years the classic Margaria step-test for anaerobic power has been largely replaced by bicycle ergometer tests, the most popular of these being the Wingate Anaerobic Test (WAnT). The purpose of this study was to examine the relationship between the WAnT and sprint-run times and to determine the influence of age and weight on the WAnT scores. The 56 male volunteers (age 10–15 years) recruited from a track club and junior high school represented a wide range of athletic abilities. Subjects were tested for anaerobic power (5 sec output) and capacity (30 sec output) using the Wingate test procedures. Wingate scores for anaerobic power and capacity were only moderately correlated with 50 yd dash times (r = ?.53 and ?.53) and with the 600 yd run (r = ?.26 and ?.29). Partial correlations between these variables were lower when age adjusted and higher when adjusted for body weight. Results of this study indicate that the Wingate anaerobic test is only a moderate predictor of dash or run times, but becomes a stronger predictor when WAnT scores are adjusted for body weight. The high correlation of the WAnT with body weight must be taken into account when comparing the anaerobic capacity of individuals. The standing long jump would be the preferred field test of sprint-related ability because of its simplicity, but the Wingate lest has the advantage of providing a quantitative measurement of anaerobic fitness.     

压力和主观幸福感：坚韧性人格的中介作用

为了检验坚韧性人格在压力和主观幸福感关系中的中介作用,对356名大学生采用主观幸福感量表、坚韧性人格量表和大学生压力量表进行问卷调查。结果表明男女生在坚韧性人格总分及各维度均存在显著差异;压力对坚韧性人格和主观幸福感的回归效应显著,坚韧性人格在压力基础上对主观幸福感的回归效应显著,由此可知坚韧性人格在压力和主观幸福感的关系中起部分中介作用。     

The effect of learner misbehaviour on educators in Lesotho

Abstract

The aim of this study was twofold, namely to examine (1) the effect of learner misbehaviour on identified symptoms of educator burnout and stress, and (2) the possible association between demographic variables and symptoms of educator stress and burnout as a direct result of learner misbehaviour. The quantitative empirical approach was used in this study. A self-reporting questionnaire was completed by 511 educators. The data were analysed by means of frequencies, the Student's t-test and the One-way ANOVA (analysis of variance) statistic. The results are reported against the background of a diagrammatical, enumerative display of the nature and frequency of different types of misbehaviour that the respondents had to address. The results prove that learner misbehaviour in Lesotho has serious negative consequences for a relatively small percentage of respondents. Contrary to the prevailing view in the literature, the data furthermore show that learner misbehaviour in Lesotho more often impacts negatively on male and on experienced educators, than on their female and their less experienced counterparts.     

Maternal psychological functioning and children's school readiness: The mediating role of home environments for African American children

Decades of educational research has documented an achievement gap in kindergarten reading and math achievement between African American children and their European American counterparts. Research has also shown that specific parenting practices (e.g., home literacy involvement) have the potential to narrow school readiness gaps by at least half. The current study examined whether and how maternal depression and parenting stress may influence specific parenting practices, as well as whether maternal warmth, home learning stimulation and cultural socialization mediated the relation between maternal depression, parenting stress, and children's kindergarten reading and math achievement. Path analyses revealed a direct negative effect of maternal depression and parenting stress on maternal warmth, home learning stimulation, and cultural socialization. Home learning stimulation emerged as an important mediator between maternal parenting stress and math achievement. Further, maternal warmth mediated the relation between maternal depression and reading achievement. Implications for early childhood research, practice and policy are discussed.     

Becoming an academic: international perspectives

Stress during doctoral study is common; however, its presence is of concern to students as it has a deleterious impact on well-being and performance, and to the university which has a duty of care to students and the desire to promote a supportive research environment. This article reports on the qualitative findings from an online survey that sought to identify students’ experiences related to stress during the early-stage doctoral study. All newly enrolled PhD students at the University of Otago (New Zealand) received invitations to participate and respond to two questions related to stress during the early-stage doctoral study. In total, 152 survey responses were acquired from 352 first-year PhD students (response rate 43.2%). Nine main areas of concern were identified from an inductive thematic analysis of participants’ responses. Key stressors were time pressure, uncertainty about doctoral processes, sense of belonging in scholarly communities, and financial pressures. Some findings are contrary to previous research with novel perceptions on the student–supervisor relationship, different financial issues, and transition stresses contrary to previous research; this may reflect the changed academic landscape of doctoral studies. Findings provide insight into potential support strategies to better support early-stage PhD students.     

Leadership succession

In the year 2007 in Scotland, in common with countries elsewhere in the world, the difficulty of recruiting high-calibre school leaders was becoming an increasing concern. The recruitment and retention study, commissioned by the Scottish Government and undertaken by three universities (Cambridge, Edinburgh and Glasgow), was charged with exploring the reasons for the shortfall of appropriate applicants. The study involved a national survey of teachers and head teachers, discussions with local authority administrators and follow-up interviews with a sample of respondents. The study identified on the one hand a common core of ‘satisfiers’ and ‘dissatisfiers’ of headship together with incentives and disincentives to apply for the job. A range of strategies adopted to cope with the pressures of the job illustrate the degree to which individuals respond by simply drowning in excessive paperwork and multiple accountabilities or are able to be adventurous and risk-taking with an ability to ‘fly below the radar’.     

壳聚糖对水分胁迫下青稞幼苗部分生理指标的影响

以青稞为实验材料,通过水培实验法探究了不同浓度壳聚糖（CTS）预处理对12％聚乙二醇（PEG）胁迫下青稞幼苗部分生理指标的影响．结果显示,12％PEG胁迫下青稞幼苗叶片含水量、叶绿素相对含量和可溶性蛋白含量均下降,经适宜浓度的CTS预处理,能在一定程度上抑制青稞幼苗含水量的下降,提高叶绿素相对含量和可溶性蛋白含量．因此,适宜浓度的壳聚糖可以增强青稞幼苗的抗旱能力,减轻水分胁迫对青稞幼苗造成的伤害．     

民办高职教师职业压力与离职倾向实证研究

以301名民办高职院校教师为被试样本,实证分析了民办高职院校教师职业压力、离职倾向现状。通过层级回归分析法处理数据,得出结论：职业压力对离职倾向存在正向预测作用,职业压力的五个因子学校管理与教师待遇、角色职责、自身发展、学生因素、人际关系对离职倾向具有显著影响。因此,政府和学校应采取有效措施缓解民办高职院校教师职业压力,以提高教师工作满意度,降低离职倾向,稳定教师队伍,促进学校的健康发展。