太极拳对老年人NK细胞的影响

人类进入老龄化社会,对衰老机制的研究越来越引起人们的重视.许多研究表明,运动是延缓机体衰老的有效手段之一.通过城镇老年妇女(55～65岁)每天习练太极拳,观察太极拳对老年人NK细胞的影响.结果发现:经过6个月的太极拳练习,老年人血液中NK细胞的含量增加;一次性太极拳练习,可明显提高血液NK细胞的百分含量,表明太极拳运动可能提高机体的免疫机能,增强老年人抗疾病的能力.     

Clinical implications of exercise immunology

Maintaining leanness and a physically active lifestyle during adulthood reduces systemic inflammation, an underlying factor in multiple chronic diseases. The anti-inflammatory influence of near-daily physical activity in lowering C-reactive protein, total blood leukocytes, interleukin-6, and other inflammatory cytokines may play a key role in lowering risk of cardiovascular disease, certain types of cancer, type 2 diabetes, sarcopenia, and dementia. Moderate exercise training causes favorable perturbations in immunity and a reduction in incidence of upper respiratory tract infection (URTI). During each bout of moderate exercise, an enhanced recirculation of immunoglobulins, neutrophils, and natural killer cells occurs that persists for up to 3-h post-exercise. This exercise-induced surge in immune cells from the innate immune system is transient but improves overall surveillance against pathogens. As moderate exercise continues on a near-daily basis for 12–15 weeks, the number of symptoms days with URTI is decreased 25%–50% compared to randomized sedentary controls. Epidemiologic and animal studies support this inverse relationship between URTI risk and increased physical activity.     

三江平原小叶章湿地枯落物在不同水位梯度上的分解及硫素释放动态

利用分解袋法，研究了小叶章枯落物在不同水位梯度上的分解动态和硫素释放情况，结果表明：在450天的分解试验中，小叶章枯落物在不同水位梯度上具有相同的分解模式，均为快－慢交替变化的模式，干物质残留率沿着水位梯度从洼地边沿到中心呈逐渐减少的趋势，分解速率表现为逐渐增大，水分条件是影响小叶章枯落物分解的一个重要因素。在不同的水位梯度上枯落物中硫的浓度呈波动性变化，这种变化和干物质损失率呈线性相关，分解450天后，枯落物残体中总硫浓度沿着水位梯度从洼地边沿到中心依次为：0.588、0.508、0.404、0.359和0.306g.kg-1，均低于初始浓度，且沿着洼地边沿向中心依次降低。S的释放模式为淋溶－固持－释放，其中枯落物残体中C：S是决定其释放模式的主要因素，当C：S高于1620.34~2430.81时，外源硫被固持，当C：S低于805.17~1070.47时，枯落物中的硫被释放，但硫的固持量或释放量受水分条件的制约，沿着水位梯度由无积水到常年积水区即由小叶章湿草甸到漂筏苔草沼泽（由B到F点），硫的固持量依次增加，释放量逐渐减少。     

姚文元的"棍子"式批评及其特征

中国的极左政治催生了一批职业文化杀手，姚文元无疑是其中最狠毒的一个。姚文元的评论文章集“十七年”极左文艺思想之大成，代表了中国当代文学批评史上最为恶劣的文风。这种文学批评在“十七年”之所以能畅通无阻，内因是姚文元善用政治投机的手段向上爬，外因是当时不断发动的政治运动、极左的文艺政策，均需要寻找姚文元式的“棍子”为其错误做法鸣锣开道。姚文元文艺批评的主要特征是“左”，而非右。     

孤独生命的诗意阐释--漫论余华小说的生命意识

余华注重刻画孤独，展示人生鬼态，揭示出人性的丑恶。但又充满了家园之恋、故土情结和对生命的哲理性思考。在揭示一定的宿命主题时，以抒情的笔调讴歌了生命的价值，用流水的意象表现对生命的终极关怀，那种关怀是热烈、饱满而又奔放的。     

木兰拳锻炼对老年人机体免疫调节作用的机制分析

研究目的:观察6个月木兰拳锻炼对老年人机体免疫机能的影响.研究方法:采用自身配对检验的方法,测定6个月木兰拳锻炼前后空腹安静状态下 NK 细胞活性变化.研究结果表明:经过6个月木兰拳的锻炼,受试者 NK 细胞活性明显提高,具有显著差异,证实长期木兰拳锻炼能有效地调节老年人的免疫机能.     

垃圾运输问题的模型及其求解

本文通过垃圾运输问题的模型建立与求解,总结出这类问题的一般性解法,即根据实际问题构造恰当的有向或无向赋权图,把问题转化成图论中的TSP问题,通过解决这类TSP问题,从而使原问题获得满意的解答.     

Examining youth perceptions and social contexts of litter to improve marine debris environmental education

Abstract

Youth have astute observations about site-specific personal and environmental factors that contribute to littering and marine debris, and they have a strong potential to act as change agents in communities. Interactions with youth in Pinellas County Florida add insights into a growing body of research on environmental education and marine debris prevention. This study assessed perceptions of marine debris and littering behaviors through group discussions with middle school and high school students (N = ～44), evaluations at summer camp programs (N = ～31) and pre- and post-assessments of environmental field trips (pre-assessment N = ～120; post-assessment N = ～140). Youth showed high initial awareness of the effects of marine debris on the environment but showed less understanding about the role of watersheds and biodegradation in marine litter issues. A majority of youth attributed others’ littering behavior to dispositional factors, like laziness, while attributing their own littering to situational factors, like poorly placed bins. Student observations of educators and parents also influenced littering behaviors and willingness to act. To reduce littering, education and outreach programs need to (1) provide opportunities for ongoing assessment of complex marine debris topics, (2) align visual and written or verbal messages, (3) reduce actor/observer bias related to littering behaviors, and (4) support adult role models.     

Australian Waste Wise Schools Program: Its Past,Present, and Future

The Waste Wise Schools program has a longstanding history in Australia. It is an action-based program that encourages schools to move toward zero waste through their curriculum and operating practices. This article provides a review of the program, finding that it has had notable success in reducing schools’ waste through a “reduce, reuse, and recycle” (or “three Rs”) approach. Since the program's conception, an evaluation process has continually occurred alongside the actual program. This report presents the most recent program evaluation results: a 2007 statewide survey that was administered to 1,015 primary (elementary) and secondary teachers. The article outlines the past, present, and future directions of the Waste Wise Schools program and, in doing so, discusses the broader implications for school-based environmental education programs. In particular and of most significance, the findings reveal a growing sustainability culture in Australian schools and communities.     

马尾松阔叶树混交林凋落物浅析

针阔混交林凋落物研究中,马×拉、马×青、马×闽、马×格、马×苦等混交群落,这5个群落以及马尾松纯林凋落物表层的化验分析结果,枯叶占优势,马×苦混交群落最高,马尾松纯林最低。营养分析A层的凋落物的N及Ca的含量最高,其平均值分别为:0.80%和1.26%,5种元素含量大小为:Ca>N>Mg或K>P。马×闽混交群落中Mg含量最小。