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991.
本文采用实证调研方法,通过对湖南省8所新升本科院校图书馆现有电子资源、参考服务模式进行比较,总结了湖南省专升本院校图书馆参考咨询的特点、发展状况及困境,并进一步探讨了湖南省专升本院校图书馆参考咨询的发展思路.参考文献4.  相似文献   
992.
本文主要运用文献资料法,从生命哲学的视阈思考新时代学校体育中的生命教育问题.结论:塑造生命是我国学校体育教育的发展逻辑主线;人的生命存在是新时代学校体育的逻辑起点,新时代学校体育的本质功能是生命教育;尊重生命规律,回归生命本原,建构完满与整全的人生,是新时代学校体育教育本源回归的意义所在.新时代学校体育生命教育的转向,...  相似文献   
993.
姜宛贝  刘卫东 《资源科学》2021,43(4):722-732
改革开放以来,中国经历了由东部率先发展到区域协调发展的区域战略调整,中国经济空间格局发生较大改变.探究CO2排放量对经济空间格局演变的响应,对中国尽早实现CO2排放达峰目标、确保可持续发展具有重要意义.本文在刻画1985-2017年中国经济空间格局演变特征的基础上,基于LMDI因素分解方法分析了中国CO2排放的驱动因素...  相似文献   
994.
灵敏度分析方法目前主要被运用于利润预测分析,而很少被运用到长期投资项目评估特别是对经营现金净流量的预测中。这里拟对此方法用于经营现金净流量分析的适用性进行探讨,试图通过计算项目经营现金净流量的灵敏系数来把握经营现金净流量的变动规律,从而为正确计算净现值指标和项目最优决策提供依据。  相似文献   
995.
Molecular hydrogen exerts biological effects on nearly all organs. It has anti-oxidative, anti-inflammatory, and anti-aging effects and contributes to the regulation of autophagy and cell death. As the primary organ for gas exchange, the lungs are constantly exposed to various harmful environmental irritants. Short- or long-term exposure to these harmful substances often results in lung injury, causing respiratory and lung diseases. Acute and chronic respiratory diseases have high rates of morbidity and mortality and have become a major public health concern worldwide. For example, coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global pandemic. An increasing number of studies have revealed that hydrogen may protect the lungs from diverse diseases, including acute lung injury, chronic obstructive pulmonary disease, asthma, lung cancer, pulmonary arterial hypertension, and pulmonary fibrosis. In this review, we highlight the multiple functions of hydrogen and the mechanisms underlying its protective effects in various lung diseases, with a focus on its roles in disease pathogenesis and clinical significance.  相似文献   
996.
This study explores how horizontal/vertical individualism and collectivism (HVIC) orientations influence electronic word-of-mouth (eWOM) (i.e., opinion leadership and opinion seeking) in social media. Online survey panel data through Amazon MTurk were collected from American social media users to address the research purpose. The results, using the structural equation modeling, show that the paths from horizontal individualism to opinion leadership, vertical individualism to opinion leadership and opinion seeking, horizontal collectivism to opinion leadership, and vertical collectivism to opinion leadership and opinion seeking were significant. This study provides theoretical and managerial implications regarding the influence of HVIC orientations on eWOM in social media.  相似文献   
997.
The purpose of this study was to examine CHO ingestion on a cognitive task using a field-simulated time-trial (TT) under hypoxia in well-trained triathletes. Ten male triathletes (age: 22.1 ± 1.1 years; VO2max: 59.4 ± 1.4 ml/kg/min) participated in this double-blind/crossover/counter-balanced design study. Participants completed 3 TT trials: 1) normoxic placebo (NPLA; FiO2 = 20.9%), 2) hypoxic placebo (HPLA; FiO2 = 16.3%), and 3) hypoxic CHO (HCHO; 6% CHO provided as 2 ml/kg/15 min; FiO2 = 16.3%). During the TT, physiological responses (SpO2, HR, RPE, and blood glucose/lactate), cognitive performance, and cerebral haemodynamics were measured. Hypoxia reduced TT performance by ~3.5–4% (p < 0.05), but CHO did not affect TT performance under hypoxia. For the cognitive task, CHO slightly preserved exercise-induced cognitive reaction speed but did not affect response accuracy during hypoxic exercise. However, CHO did not preserve the decreased Hb-Diff (cerebral blood flow, CBF) and increased HHb in the prefrontal lobe (p < 0.05) during hypoxic exercise, and CHO failed to preserve hypoxia-suppressed prefrontal CBF and tissue oxygen saturation. In conclusion, the present study demonstrates that CHO is effective in sustaining reaction speed for a cognitive task but not promoting TT performance during hypoxic exercise, which would be important for strategy-/decision-making when athletes compete at moderate high-altitude.  相似文献   
998.
Purpose: The aim of this study was to test the effects of chair-based exercise programs on salivary stress hormones, physical fitness, and functional autonomy of institutionalized older women. Method: In total, 47 participants (80 ± 8.04 years old) were recruited and allocated into three groups: chair-based aerobic exercises (CAE, n = 19), chair-based elastic-band strength exercises (CSE, n = 15), and a control group (CG, n = 13). A 14-week exercise intervention was done for the CAE and CSE groups, two times per week, in no consecutive days. Members of the CG did not participate in any type of exercise but kept their regular lifestyle. Fear of falling, autonomy, physical fitness, salivary cortisol, and alpha-amylase levels were assessed before and after the intervention. Results: The CAE group improved upper and lower body strength, agility–dynamic balance, and autonomy, with fear of falling decreasing significantly (p < .05, moderate effect size). Both exercise groups showed a trend toward an increase in salivary alpha-amylase levels (CAE = 43%, d = .31, and CSE = 44%, d = .41). Conclusion: Both exercise programs were able to improve functional autonomy, even in elders older than 80 years of age. It might be interesting to investigate the effectiveness of combining both aerobic and strength exercises in a unique protocol. The modulation effect of exercise in the hormonal responses needs to be further explored.  相似文献   
999.
功能训练的理念来源于康复领域,现已逐步应用到运动训练中。由于乒乓球运动的项目特征,乒乓球运动员肩关节、腰椎关节、膝关节、踝关节、腕关节等部位容易出现运动损伤。通过对乒乓球运动员常出现的功能问题进行分析,寻找存在的常见问题,进而提出相应的功能训练建议。乒乓球运动员可根据情况,增加改善肩关节、胸椎关节、髋关节、踝关节的活动范围的训练,提高肩胛骨、核心和下肢稳定性的训练,以及改善肩袖、躯干肌力不平衡的训练,通过针对性的功能训练有效减少乒乓球运动员损伤的发生。  相似文献   
1000.
In this study, we examined the factor structure and reliability of the Korean Quality of Life (KQoL) survey and compared the KQoL survey to both the World Health Organization Quality of Life-Brief Version (WHOQOL-BREF) and the Satisfaction with Life Scale (SWLS). We also assessed associations between KQoL scores and physical activity (PA) participation. Participants were 557 (male = 281, female = 276) healthy Korean adults with ages between 18 and 71 years (M = 33.2, SD = 14.2). Results of confirmatory factor analyses confirmed the 7-subscale model and indicated acceptable values supporting convergent validity (χ2 = 1,678.758, df = 443, p < .001, RMSR = .045, RMSEA = .071, TLI = .880, CFI = .892). Correlations of KQoL subscales with similar subscales of WHOQOL-BREF and with SWLS supported concurrent validity. Results confirm that the KQoL survey can assess multidimensional aspects of quality of life (QoL), including spiritual, physical, social, and psychological. KQoL scores were positively related to PA participation, in line with previous research supporting the positive association of PA with QoL.  相似文献   
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