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41.
The purpose of this study is to examine the relationship between perceived ageism and depression in later life and to clarify the mechanism underlying this relationship by examining the mediating effects of self-perception of aging and purpose in life. The Health and Retirement Study surveys were used for this secondary analysis of data. The sample included 3,991 older adults, and structural equation modeling (SEM) analyses using structural regression models were conducted. SEM analyses revealed that full mediation effects of self-perception of aging and purpose in life exist. Older adults who perceive ageism are likely to have negative self-perception of aging, and this negative view of their own aging is likely to decrease purpose in life and increase depressive symptoms. The results of this study imply that more efforts and resources are necessary to reduce ageism and its negative effect on depression among older adults. Additionally, the current study suggests the necessity of anti-ageism policies and social services. Increasing positive self-perception of aging, purpose in life, and resilience could be the key to a better quality of life for older adults. 相似文献
42.
美国优质网络课程的案例介绍 总被引:1,自引:0,他引:1
近十年来,我国高校网络课程建设成果显著,但其中暴露出的理论与实践相脱离的现象也比较严重。通过介绍美国德克萨斯A&M大学Dooley教授开设的网络课程《远程教育的高级方法》,尝试剖析其作为优质网络课程在管理平台、教学设计、交互安排、评价方法以及支持服务等方面所具有的特征,以期与国内远程教育的研究者和实践者分享经验。 相似文献
43.
Xier Luo Yu Zhou Bing Zhang Yi Zhang Xiaobo Wang Tong Feng Zhipeng Li Kuiqing Cui Zhiqiang Wang Chan Luo Hui Li Yanfei Deng Fenghua Lu Jianlin Han Yongwang Miao Huaming Mao Xiaoyan Yi Cheng Ai Shigang Wu Alun Li Zhichao Wu Zijun Zhuo Do Da Giang Bikash Mitra Mohammad Farhad Vahidi Shahid Mansoor Sahar Ahmed Al-Bayatti Eka Meutia Sari Neena Amatya Gorkhali Sigit Prastowo Laiba Shafique Guoyou Ye Qian Qian Baoshan Chen Deshun Shi Jue Ruan Qingyou Liu 《国家科学评论(英文版)》2020,7(3):686
Domesticated buffaloes have been integral to rice-paddy agro-ecosystems for millennia, yet relatively little is known about the buffalo genomics. Here, we sequenced and assembled reference genomes for both swamp and river buffaloes and we re-sequenced 230 individuals (132 swamp buffaloes and 98 river buffaloes) sampled from across Asia and Europe. Beyond the many actionable insights that our study revealed about the domestication, basic physiology and breeding of buffalo, we made the striking discovery that the divergent domestication traits between swamp and river buffaloes can be explained with recent selections of genes on social behavior, digestion metabolism, strengths and milk production. 相似文献
44.
Droplet microfluidics enables powerful analytic capabilities but often requires workflows involving macro- and microfluidic processing steps that are cumbersome to perform manually. Here, we demonstrate the automation of droplet microfluidics with commercial fluid-handling robotics. The workflows incorporate common microfluidic devices including droplet generators, mergers, and sorters and utilize the robot''s native capabilities for thermal control, incubation, and plate scanning. The ability to automate microfluidic devices using commercial fluid handling will speed up the integration of these methods into biological workflows. 相似文献
45.
Mikhail Santos Cerqueira Jose Diego Sales Do Nascimento Daniel Germano Maciel Jean Artur Mendonca Barboza Wouber Herickson De Brito Vieira 《运动与健康科学(英文)》2020,9(2):152-159
Purpose:To investigate whether blood flow restriction(BFR) without concomitant exercise mitigated strength reduction and atrophy of thigh muscles in subjects under immobilization for lower limbs.Methods:The following databases were searched:PubMed,CINAHL,PEDro,Web of Science,Central,and Scopus.Results:The search identified 3 eligible studies,and the total sample in the identified studies consisted of 38 participants.Isokinetic and isometric torque of the knee flexors and extensors was examined in 2 studies.Cross-sectional area of thigh muscles was evaluated in 1 study,and thigh girth was measured in 2 studies.The BFR protocol was 5 sets of 5 min of occlusion and 3 min of free flow,twice daily for approximately 2 weeks.As a whole,the included studies indicate that BFR without exercise is able to minimize strength reduction and muscular atrophy after immobilization.It is crucial to emphasize,however,that the included studies showed a high risk of bias,especially regarding allocation concealment,blinding of outcome assessment,intention-to-treat analyses,and group similarity at baseline.Conclusion:Although potentially useful,the high risk of bias presented by original stodies limits the indication of BFR without concomitant exercise as an effective countermeasure against strength reduction and atrophy mediated by immobilization. 相似文献
46.
Changwook Kim 《Inter-Asia Cultural Studies》2019,20(1):39-55
This study aims to reconsider and re-evaluate the rapid circulation of global creative city policy from the viewpoint of its creative workforce by focusing on the case of Yokohama, Japan. To shed light on this workforce’s everyday experiences and labor subjectivity, this investigation draws ideas from recent research trends of “creative labor” from the field of media and cultural studies, sociology of work, and political economy of communication. Based on in-depth interviews and participant observations, this research focuses on how the ethical and moral dimensions of labor subjectivity in creative work are prominently important in explaining Yokohama workers’ everyday living and working experiences as creative labor. Unexpectedly, this study found that these moral and ethical sentiments and actions, which take on the role of retaining their labor motivation, actually limit the development of political subjects who can resist given precarious working conditions and thereby hinder them from building a collective solidarity as “workers.” Thus this investigation concludes that the creative worker’s subjectivity retreats to solely a moral dimension rather than to a political one. Through this finding, this study explores whether the articulation of moral-political and social values in the course of cultural work can evolve from creative workers’ moral and ethical sensitivities and actions. 相似文献
47.
48.
Taeyou Jung Yumi Kim Hyosok Lim Konstantinos Vrongistinos 《Sports biomechanics / International Society of Biomechanics in Sports》2019,18(3):297-307
The purpose of this study was to investigate kinematic and spatiotemporal variables of aquatic treadmill walking at three different water depths. A total of 15 healthy individuals completed three two-minute walking trials at three different water depths. The aquatic treadmill walking was conducted at waist-depth, chest-depth and neck-depth, while a customised 3-D underwater motion analysis system captured their walking. Each participant’s self-selected walking speed at the waist level was used as a reference speed, which was applied to the remaining two test conditions. A repeated measures ANOVA showed statistically significant differences among the three walking conditions in stride length, cadence, peak hip extension, hip range of motion (ROM), peak ankle plantar flexion and ankle ROM (All p values < 0.05). The participants walked with increased stride length and decreased cadence during neck level as compared to waist and chest level. They also showed increased ankle ROM and decreased hip ROM as the water depth rose from waist and chest to the neck level. However, our study found no significant difference between waist and chest level water in all variables. Hydrodynamics, such as buoyancy and drag force, in response to changes in water depths, can affect gait patterns during aquatic treadmill walking. 相似文献
49.
This study attempts to answer two questions. First, can a single cultural event impact the stock prices of a wide range of companies and sectors? Second, was the positive stock market response in the information technology (IT) sector as well as performing arts sector significant? To answer these questions, we examine whether a hit pop single, “Gangnam Style” by Park Jae-Sang in 2012, affected related sectors of the Korean stock market and whether market reactions went beyond the stock price of the singer’s agency to affect those of other firms. We use an event study approach. The results show two notable empirical findings. First, although the findings indicating abnormal returns and cumulative abnormal returns appear mixed, the overall results imply that the unprecedented worldwide hit single by the South Korean singer positively affected the Recreation & Culture and Digital Content sectors. In other words, the market interpreted the event as good news, with shareholders expecting positive effects on the related sectors. Second, a positive stock market response was observed in the IT sector as well. 相似文献
50.
Controversial results reported in past research pertaining to the effectiveness of sport-based physical activity interventions on weight loss. The purpose of this study was to assess the impact of sport-based physical activity intervention on body weight in children and adolescents using a meta-analysis. Academic Search Complete, Education Source, ERIC, Medline, ProQuest, PsycINFO and SportDiscus databases were searched from January 2000 to April 2015. Eighteen studies met following inclusion criteria: sport-based intervention studies; subjects aged 6–18 years; reported body weight; published in peer-reviewed journals written in English. The mean intervention duration was 17.72 weeks. The overall effect size (ES) was 0.52 (Cohen’s d (ES) = 0.52, 95% CI = 0.08, 0.95, P = 0.021), using a random effects model. Moderator analyses results showed that the Q statistic for the sport type (individual sport or team sport, Qbetween (Qb) = 14.52, df = 1, P = 0.001) and diet control (Qbetween (Qb) = 8.85, df = 1, P = 0.001), explained the heterogeneity of ESs. Our study showed that there was a moderate overall effect of sport-based physical activity intervention on body weight reduction. The team sport type (ES = 1.05, 95% CI = 0.44, 1.66) and diet control group (ES = 0.84, 95% CI = 0.26, 1.41) appeared to be more effective in reducing body weight. 相似文献