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41.
建国初期,教育的阶级性和功利性成为高等教育的铁律,政治运动和政治性学术批判,对高校师生阅读产生了重大影响,红色苏联文化作品成为当时主要课外阅读时尚。  相似文献   
42.
This paper outlines a history of the union organizing of the American Newspaper Guild at Thomson Newspapers’ Peterborough Examiner in Canada from 1968 to 1969. It examines the communication tools that union members used to facilitate this labor organizing and “bite back” at the profitable Thomson chain. Peterborough newsworkers went on strike from November 1968 to April 1969 over union recognition. During the strike, the union members built an unprecedented alliance with Ontario university students, collaboratively launching a strike newspaper called the Peterborough Free Press. Expanding on the concept of temporary labor convergence, this paper considers how strike newspapers can be seen as a form of alternative journalism that newsworkers use as a campaigning tool to communicate their struggles to the public and put pressure on news corporations to bargain with them. This case study is situated in the local institutional contexts of labor relations at the Peterborough Examiner and the news industry in Peterborough, where Thomson Newspapers had a media monopoly. It is based on labor standpoint and signal juncture analyses of union archival documents and newspaper content. The research ultimately suggests that newsworkers should not only focus on communication tools but also build bridges with community members.  相似文献   
43.
BackgroundPlanctomycetes is a phylum of biofilm-forming bacteria with numerous biosynthetic gene clusters, offering a promising source of new bioactive secondary metabolites. However, the current generation of chemically defined media achieves only low biomass yields, hindering research on these species. We therefore developed a chemically defined medium for the model organism Planctopirus limnophila to increase biomass production.ResultsWe found that P. limnophila grows best with a 10 mM sodium phosphate buffer. The replacement of complex nitrogen sources with defined amino acid solutions did not inhibit growth. Screening for vitamin requirements revealed that only cyanocobalamin (B12) is needed for growth. We used response surface methodology to optimize the medium, resulting in concentrations of 10 g/L glucose, 34 mL/L Hutner’s basal salts, 23.18 mM KNO3, 2.318 mM NH4Cl and 0.02 mg/L cyanocobalamin. The analysis of amino acid consumption allowed us to develop a customized amino acid solution lacking six of the amino acids present in Aminoplasmal 10%. Fed-batch cultivation in a bioreactor using the optimized medium achieved a final ΔOD600 of 46.8 ± 0.5 after 108 h, corresponding to a cell dry weight of 13.6 ± 0.7 g/L.ConclusionsThe optimized chemically defined medium allowed us to produce larger amounts of biomass more quickly than reported in earlier studies. Further research should focus on triggering P. limnophila biofilm formation to activate the gene clusters responsible for secondary metabolism.How to cite: Kruppa OC, Gerlach D, Fan R, et al. Development of a chemically defined medium for Planctopirus limnophila to increase biomass production. Electron J Biotechnol 2021;54. https://doi.org/10.1016/j.ejbt.2021.09.002.  相似文献   
44.
成年哺乳动物神经发生仅发生在侧脑室的室管膜下层和海马齿状回的颗粒细胞下层两个区域。综述了检测神经发生的主要方法,从神经递质、生长因子、营养因子等方面探讨了运动诱发神经发生的相关机制,并分析了运动诱发的神经发生对学习记忆能力的意义。  相似文献   
45.
ABSTRACT

Ankle sprains are the most common injury in regular badminton players and usually occur at the end of a match or training. The purpose of the present study was to examine the influence of fatigue produced by badminton practice on the lower limb biomechanics of badminton players. It was hypothesized that fatigue induces ankle kinematic and lower leg muscle activity changes which may increase the risk of ankle sprain. Ankle kinematics, ankle kinetics and muscles activities of 17 regular badminton players were recorded during lateral jumps before and after an intense badminton practice session. Post-fatigue, ankle inversion at foot strike and peak ankle inversion increased (+2.6°, p = 0.003 and +2.5°, p = 0.005, respectively). EMG pre-activation within 100 ms before foot landing significantly decreased after fatigue for soleus (?23.4%, p = 0.031), gastrocnemius lateralis (?12.2%, p = 0.035), gastrocnemius medialis (?23.3%, p = 0.047) and peroneus brevis (?17.4%, p = 0.036). These results demonstrate impaired biomechanics of badminton players when fatigue increases, which may cause a greater risk of experiencing an ankle sprain injury.  相似文献   
46.
首先从情绪工作的定义、特征出发分析教师是属于高情绪工作者,之后阐述情绪工作的调节策略以及影响调节策略的相关因素,以期为研究教师职业提供一个新视角。  相似文献   
47.
针对定向运动核心理念教学在高校体育教学中的方法及形式的时效性、指导思想的时效性以及内容的时效性进行研究,并提出提高定向运动核心理念教学的优化措施.  相似文献   
48.
This study explored how developmentally appropriate practices influenced the affordances of a multitouch surface in an early childhood classroom. Children, ages 4 to 5 years old, were videotaped while engaged in a storymaking application on a multitouch table. As a result of the study, we found that some challenges with the functionality undermined children's autonomous control. The researchers observed numerous instances of issues with control of the medium, including height of the table, sensitivity to multiple types of touch, and limited instructions and prompts. Implications for future research and practice are discussed.  相似文献   
49.
运用傅立叶方程建立了氟化体系稀土电解槽的温度场的有限元模型,采用VC6.0编程制作了相应的软件,并对导热系数、密度、比热等相关参数进行了运行计算研究.结果表明,建立的数学模型和编制的软件对稳态温度场的数学模拟计算结果与实际测试的结果基本吻合.可为新一代稀土电解槽体的开发设计提供参考.  相似文献   
50.
土地革命时期的少年先锋队是一个革命青年的半武装组织。在中国共产党、共青团和苏维埃政府的关心下,少年先锋队领导苏区青年为争取自身阶级利益,保卫苏维埃政权,努力学习知识,并积极投身于革命运动中。他们参与阶级斗争,帮助政府实现各项政治经济政策;开展拥军优属活动,帮助工农群众进行生产建设;训练和培养了大批红军后备力量,帮助红军、赤卫军、游击队保卫苏区政府和人民的安全,并为前线输送了大量优秀战士。在近代中国青年运动史上,少年先锋队组织有着不可磨灭的伟大贡献。  相似文献   
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