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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.
Language education has often been conducted based on monoglossic ideologies that keep L1 and L2 separate, a practice that receives growing criticism as out of sync with today’s multilingual globalized world. Informed by interdependence hypotheses and translanguaging theory, this research study explored the effects of a pluri-centric approach to learning L1 and L2 simultaneously. Through a bilingual intervention course with data collected from interviews, parents’ logbooks, observation field notes, questionnaires, and L1 and L2 reading and writing tests, this case study (n = 9) revealed that the approach effectively improved learners’ L1 and L2 proficiency, learning behaviour outside the classroom, self-efficacy, and confidence. Overall, the participants also perceived the bilingual course as effective, efficient, and innovative. The study provides a basis to reflect upon transferrable skills and core underlying proficiency as powerful concepts to draw upon in enhancing bilingual proficiency and effecting positive changes in learners’ behaviour and psychological well-being.  相似文献   
3.
研究旨在探讨一次不同抗阻训练方案对外周血CD4+和CD8+T淋巴细胞亚群迁移和凋亡的影响。通过实验法15名无训练经历的健康青年男性分别进行一次以促进肌肉肥大(H-RT组,方案:70%1RM,10RM,3组,组间间歇1.5 min)和以改善肌肉耐力(E-RT组,方案:60%1RM,15RM,3组,组间间歇1 min)为目的的抗阻训练方案。并于训练前、训练后即刻、训练后2 h和24 h利用流式细胞仪测定表面标志物CX3CR1和annexin V表达量检测CD4+、CD8+T淋巴细胞亚群迁移和凋亡(用阳性表达率表示)。得出以下数据:(1)CD4+T细胞在H-RT组运动后即刻和运动后24 h,annexin V和CX3CR1阳性表达率显著性升高(P<0.05)。E-RT组annexin V阳性表达率在运动后即刻降低(P<0.05),24 h显著性升高(P<0.05);CX3CR1阳性表达率仅在运动后即刻升高(P<0.05)。(2)CD8+T细胞在H-RT组和E-RT组运动后即刻和运动后24 h,annexin V和CX3CR1阳性表达率均显著性升高(P<0.05)。通过对以上数据的分析,研究得出以下结论:CD4+T淋巴细胞亚群对于急性抗阻训练的免疫反应存在运动方案依赖性。  相似文献   
4.
Automated keyphrase extraction is a fundamental textual information processing task concerned with the selection of representative phrases from a document that summarize its content. This work presents a novel unsupervised method for keyphrase extraction, whose main innovation is the use of local word embeddings (in particular GloVe vectors), i.e., embeddings trained from the single document under consideration. We argue that such local representation of words and keyphrases are able to accurately capture their semantics in the context of the document they are part of, and therefore can help in improving keyphrase extraction quality. Empirical results offer evidence that indeed local representations lead to better keyphrase extraction results compared to both embeddings trained on very large third corpora or larger corpora consisting of several documents of the same scientific field and to other state-of-the-art unsupervised keyphrase extraction methods.  相似文献   
5.
[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   
6.
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   
7.
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   
8.
Abstract

The 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   
9.
ABSTRACT

Previously, 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   
10.
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   
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