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1.
通过浸渍干燥法制备了可集成至纺织品中的基于Ti3C2Tx的可穿戴温度传感器。所制备的柔性温度传感材料显示出负的电阻温度系数,其值为-0.36%℃-1,能满足可穿戴温度传感器的要求。展示了柔性温度传感器对温水与冷水的感知能力,验证其在实际场景中的应用潜力。  相似文献   
2.
目的:分析青春期前期、中期和后期三个阶段青少年动作发展的趋势及性别差异,验证"青春期笨拙"现象是否存在,为青少年动作表现准确评估与有效训练提供依据。方法:选取处于青春期前期、中期和后期三个阶段的共302名青少年,采用BOT-2SF分别对其动作表现进行测试。测试包含4个维度8个指标:精细动作控制(精细动作准确性、精细动作整合)、手部协调(手灵巧度、上肢协调)、躯干协调(两侧协调、平衡)、力量与敏捷(速度和敏捷、力量)。结果:(1)测试总得分和具体指标(除平衡能力外)得分,阶段主效应显著,且青春期中期优于青春期前期;(2)性别主效应显著的指标有精细动作准确性、手灵巧度、上肢协调和力量;(3)性别和阶段交互效应显著的指标包含手灵巧度、跑步速度和灵敏性。结论:(1)整个青春期阶段男生、女生的动作表现均未呈现出暂时下降的现象,"青春期笨拙"现象并不存在;(2)动作表现在部分阶段的部分指标上存在性别差异。力量和上肢协调性方面,青春期三个阶段中男生都优于女生;精细动作准确性方面,青春期三个阶段中女生优于男生;手灵巧度方面,青春期中期女生优于男生;速度与敏捷方面,青春期后期男生优于女生;手灵巧度方面,青春期后期男生优于女生;(3)性别差异引起的动作表现随青春期的发展而逐渐增大。  相似文献   
3.
现有研究对于政府对制造业补贴能否提高制造业绩效存有争议。通过理论分析认为,研发投入是提高制造业绩效的有效途径,而且相比于一般制造业研发投入对高技术产业的绩效提高效果更为明显。同时研发投入需要大量资金,如果一味增加研发投入,可能挤占其他部门资金。因此,政府补贴能够通过提高企业的研发投入促进企业绩效提升,而且对于高技术产业企业绩效提升的正面影响要大于对一般制造业;并通过A股上市企业的数据进行实证研究,证明以上研究结论。这意味着政府应该对企业进行补贴,而且应该重点补贴高技术产业。  相似文献   
4.
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   
5.
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   
6.
基于2013-2018年广东省197家重点实验室作为样本数据,综合考虑依托主体的价值导向作用,将样本分为高校、医院、研究院所、企业四组;在梳理以往文献研究的指标基础上,分别建立人才队伍、学术研究、创新研发、成果转化4个评估体系,采用CCR、BCC模型对四组样本的投入产出效率进行分析.研究结果表明,不同指标体系下四组样本的效率特征存在明显差异,人才队伍是影响高校、医院学术研究投入产出效率的主要因素,科研项目经费是影响企业、研究院所投入产出效率的主要因素.提出了基于不同评估导向的运行效率分组评价方法,以期为合理评价广东省各类科研平台创新效率提供新的视角.  相似文献   
7.
Global coastal oceans as a whole represent an important carbon sink but, due to high spatial–temporal variability, a mechanistic conceptualization of the coastal carbon cycle is still under development, hindering the modelling and inclusion of coastal carbon in Earth System Models. Although temperature is considered an important control of sea surface pCO2, we show that the latitudinal distribution of global coastal surface pCO2 does not match that of temperature, and its inter-seasonal changes are substantially regulated by non-thermal factors such as water mass mixing and net primary production. These processes operate in both ocean-dominated and river-dominated margins, with carbon and nutrients sourced from the open ocean and land, respectively. These can be conceptualized by a semi-analytical framework that assesses the consumption of dissolved inorganic carbon relative to nutrients, to determine how a coastal system is a CO2 source or sink. The framework also finds utility in accounting for additional nutrients in organic forms and testing hypotheses such as using Redfield stoichiometry, and is therefore an essential step toward comprehensively understanding and modelling the role of the coastal ocean in the global carbon cycle.  相似文献   
8.
International Guidelines have voted for PCR as the Gold Standard in COVID diagnosis. Nasoparyngeal swab is the preferred specimen for PCR. It has a high probability of diagnosing early infection. But the diagnostic sensitivity of nasopharyngeal PCR decreases with increase in lapse between the infection and presentation to hospital. This might lead to dire consequences of labelling these patients as false negative, though such patients have been proved to be potentially infective since viral shedding occurs through other body fluids (stools) for long. COVID infection reveals that the IgM antibodies start to appear as early as 5th day of infection and switches over to IgA within 2–3 days. The aim of the study was to see if COVID antibody testing be coupled with PCR for diagnosis especially in patients presenting late (more than 14 days) of onset of infection? And if the antibodies are giving values, hence can them be reported quantitatively rather than in qualitative fashion? The second objective was to see if the COVID antibody levels be used to monitor the disease severity? And if the antibody levels of SARS CoV 2 be used an indicator to monitor the recovery?  相似文献   
9.
[目的/意义] 在线医疗社区用户画像能够精练化提取患者需求、可视化描述患者特征,有助于平台管理者制定更精准的信息服务策略。[方法/过程] 在梳理在线医疗社区用户画像研究成果的基础上,提出一种在线医疗社区用户画像构建框架,并爬取百度贴吧中糖尿病社区用户数据,综合采用档案清单、复合图形、语言描述和词云方法,实现了具有4个维度和12项标签的在线医疗社区用户画像构建。[结果/结论] 该理论框架及实现方法有助于信息精准推荐、改善患者体验、提升决策质量,为在线医疗社区用户画像构建与应用提供了理论与实践指导。  相似文献   
10.
采用共沉淀法合成了Ag2O/NaNbO3复合光催化剂,并利用X射线衍射(XRD)和扫描电子显微镜(SEM)分别对其物相和形貌进行表征,用紫外可见漫反射光谱仪对其光学性质进行研究。在可见光下以罗丹明B(RhB)为目标降解物,检测了Ag2O/NaNbO3光催化剂的光催化性能。结果表明,与纯的Ag2O和纯的NaNbO3相比,Ag2O/NaNbO3复合光催化剂具有较高的光催化活性,其光催化活性的提升可能归结于p-n结的形成,使得光生电子空穴对的复合机率大大降低。  相似文献   
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