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1.
The current Coronavirus disease (Covid-19) pandemic has spread to about 220 countries of the world and has resulted in a significant number of deaths globally. Infections are still on the rise, and the impact on the global death rate could be devastating. There are fears over the likely impact of a large number of deaths on body sourcing and handling of cadavers for teaching and research. Historically, epidemics come with several challenges and have often led to some level of negligence of ethical practices and health and safety regulations associated with body sourcing and handling. The authors highlighted some emerging problems in this article, focusing on Africa and Nigeria in particular. These problems include a higher risk of coronavirus exposure for body handlers, shortage of cadavers for teaching and learning, a lack of standard regulations leading to unethical body sourcing and handling, and a lack of monitoring and collaboration needed for a well-coordinated Covid-19 pandemic response strategy. If these issues are ignored, the previous gains made in anatomical ethical practices may be destroyed. Some useful recommendations for policymaking geared toward prevention or curtailing these emerging issues have been instilled in this article. 相似文献
2.
研究新中国成立70年来体育教育专业人才培养特征与演变规律,是呈现体育教育专业发展历史的需要,是推动体育教育专业发展和改革的一项基础性工程。采用文献资料法、历史法、专家访谈法和逻辑分析法,对体育教育专业发展规模、专业定位、培养方案、课程设置、教学模式等方面开展研究,结果表明:新中国成立70年来,体育教育专业经历了学习与移植、探索与挫折、混乱与恢复、开放与改革、提速与跨越、实践与创新的演变过程。表现出专业规模不断扩大、培养目标由单一向多元发展、课程设置逐渐模块化和弹性化、选修课和实践课学时逐步增加、总学分缓慢降低、人才培养模式多样、教学方法不断更新等特征。这些演变是基于国际国内的政治、经济、文化和科技发展的历史缘由。当下,专业认证已全面铺开,坚持"一流专业"建设是培养卓越体育教师的根与本。 相似文献
3.
[目的/意义] 探究用户使用电子书意愿的影响因素,以有助于电子书产业走出缓慢的发展困境。[方法/过程] 以UTAUT2、使用满足理论为基础,从需求满足和外部情景因素两个层面构建影响因素模型,并将需求满足细化为内容需求、社交互动需求和休闲娱乐需求3个测量变量。采用问卷调查方法收集有效样本1 013份,使用AMOS21软件对模型进行验证。[结果/结论] 研究发现,需求满足、阅读习惯、价格价值、社会影响对使用意愿有正向影响作用,而激励措施对使用意愿有负向影响作用,努力期望对使用意愿的影响不显著,并依据研究结果提出促进电子书产业发展的建议。 相似文献
4.
Trevor N. Simper Cecile Morris Anthony Lynn Ciara O'Hagan Karen Kilner 《运动与健康科学(英文)》2020,9(6):645-650
BackgroundOne-hour postprandial hyperglycemia is associated with increased risk of type 2 diabetes and cardiovascular disease. Physical activity (PA) has short-term beneficial effects on post-meal glucose response. This study compared the oral glucose tolerance test results of 3 groups of people with habitually different levels of PA.MethodsThirty-one adults without diabetes (age 25.9 ± 6.6 years; body mass index 23.8 ± 3.8 kg/m2; mean ± SD) were recruited and divided into 3 groups based on self-reported PA volume and intensity: low activity < 30 min/day of moderate-intensity activity (n = 11), moderately active ≥ 30 min/day of moderate-intensity PA (n = 10), and very active ≥ 60 min/day of PA at high intensity (n = 10). Participants completed an oral glucose tolerance test (50 g glucose) with capillary blood samples obtained at baseline, 15 min, 30 min, 45 min, 60 min, 90 min, and 120 min post-ingestion.ResultsThere were no significant differences between groups for age or body fat percentage or glycated hemoglobin (p > 0.05). The groups were significantly different in terms of baseline glucose level (p = 0.003) and, marginally, for gender (p = 0.053) and BMI (p = 0.050). There was a statistically significant effect of PA on the 1-h postprandial glucose results (p = 0.029), with differences between very active and low activity groups (p = 0.008) but not between the moderately active and low activity groups (p = 0.360), even when baseline glucose level and gender differences were accounted for. For incremental area under the curve there was no significant effect of activity group once gender and body fat percentage had been accounted for (p = 0.401). Those in the low activity group took 15 min longer to reach peak glucose level than those in the very active group (p = 0.012).ConclusionThe results suggest that high levels of PA have a beneficial effect on postprandial blood glucose profiles when compared to low and moderate levels of activity. 相似文献
5.
运用文献资料法、问卷调查法等研究方法对歧视体育教师的现象进行分析。研究认为:体育教师受歧视现象的持续发生,折射出了学校体育教育的缺失。体育教师受到歧视的根源在于传统文化观念的影响、社会对体育教育的偏见、学校体育政策的偏颇、教师职业认同的迷失、个人行为形象失范等。体育教师受歧视现象的消解路径:提升体育教师社会地位,完善学校体育法律法规,优化大众媒介舆论管理,加强体育教师个人修养等。只有如此,才能从根本上扭转和消除体育教师受歧视现象的再发生。 相似文献
6.
钴酸镍纳米材料具有良好的电催化氧析出反应(Oxygen Evolution Reaction,OER)活性,是一种很有发展潜力的非贵金属电催化材料。文章以碳纤维纸为基底,采用水热合成的方法对纳米结构钴酸镍的生长进行了系统的研究,分别考察了生长温度、前驱体浓度和配比、生长时间对产物的形貌、尺寸、物相结构、OER电化学性能的影响,通过对比分析后发现在生长温度100℃、生长时间5h、镍钴比为2:1时所获得的多孔片状钴酸镍纳米结构具有最佳的OER特性。 相似文献
7.
AbstractThe Program for Cooperative Cataloging (PCC) has formal relationships with the Library of Congress (LC), Share-VDE, and Linked Data for Production Phase 2 (LD4P2) for work on Bibliographic Framework (BIBFRAME), and PCC institutions have been very active in the exploration of MARC to BIBFRAME conversion processes. This article will review the involvement of PCC in the development of BIBFRAME and examine the work of LC, Share-VDE, and LD4P2 on MARC to BIBFRAME conversion. It will conclude with a discussion of areas for further exploration by the PCC leading up to the creation of PCC conversion specifications and PCC BIBFRAME data. 相似文献
8.
Tiziana Lombardo Marie Wörle Vera Hubert Erwin Hildbrand Christina Hinterleitner Ingo Mayer 《文物保护研究》2020,65(2):65-76
ABSTRACTPreviously, heavy use of biocides for the treatment of objects made of organic materials in museum collections (e.g. ethnographic, historical collections) was very common. Now suitable decontamination methods/technologies are being sought. A decontamination treatment by li-CO2 was optimized that considered the specific requirements of museum objects. The treatment was tested on model materials artificially contaminated with biocide solutions containing dichlorodiphenyltrichloroethane (DDT), pentachlorophenol (PCP), lindane, and permethrin or cypermethrin. High decontamination was achieved for DDT, lindane, PCP, and permethrin on artificially biocide loaded wool and wood model materials. Optimal process parameter settings for li-CO2 decontamination include a single 30?min cycle for woolen materials and three sequential 30?min cycles each for wood. These methods allow a reduction of at least 90% of all biocides for wool and between 70% and 85% for wood. Decontamination of the latter was more effective for less polar biocides as DDT and permethrin. Despite a significant improvement in decontamination for wood using co-solvents such as acetone, ethanol, and methyl tertiary-butyl ether (MTBE), their use is not recommended due to the increased risk of damage to the objects, in particular if a surface coating is present. 相似文献
9.
Masahiro Horiuchi Yoko Handa-Kirihara Daijiro Abe Yoshiyuki Fukuoka 《Journal of sports sciences》2019,37(14):1638-1647
We investigated combined effects of ambient temperature (23°C or 13°C) and fraction of inspired oxygen (21%O2 or 13%O2) on energy cost of walking (Cw: J·kg?1·km?1) and economical speed (ES). Eighteen healthy young adults (11 males, seven females) walked at seven speeds from 0.67 to 1.67 m s?1 (four min per stage). Environmental conditions were set; thermoneutral (N: 23°C) with normoxia (N: 21%O2) = NN; 23°C (N) with hypoxia (H: 13%O2) = NH; cool (C: 13°C) with 21%O2 (N) = CN, and 13°C (C) with 13%O2 (H) = CH. Muscle deoxygenation (HHb) and tissue O2 saturation (StO2) were measured at tibialis anterior. We found a significantly slower ES in NH (1.289 ± 0.091 m s?1) and CH (1.275 ± 0.099 m s?1) than in NN (1.334 ± 0.112 m s?1) and CN (1.332 ± 0.104 m s?1). Changes in HHb and StO2 were related to the ES. These results suggested that the combined effects (exposure to hypoxia and cool) is nearly equal to exposure to hypoxia and cool individually. Specifically, acute moderate hypoxia slowed the ES by approx. 4%, but acute cool environment did not affect the ES. Further, HHb and StO2 may partly account for an individual ES. 相似文献
10.
地表水面精确提取是研究地表水质和水量变化的重要基础。斯里兰卡是"21世纪海上丝绸之路"的重要参与国,年降雨量丰富,但时空分布不均,斯里兰卡人民长期用水困难,研究斯里兰卡地表水体有助于斯里兰卡民生问题的解决。斯里兰卡国内散布着大量的小型水库和坑塘,这些小面积水体易受周边环境因素影响而提取困难。基于2017年7月斯里兰卡中东部地区的哨兵(Sentinel)1/2号卫星影像,对比分析单波段法、水体指数法和监督分类等水体提取方法的精度和存在的问题。结果表明,归一化水体指数法NDWI的准确率最高,分类精度达94%。 相似文献