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151.
Supplementation with anthocyanins, which are a type of flavonoids mainly found in various berries, is hypothesized to be a promising approach to lower the risk of developing cognitive decline. The aim of this systematic review was to provide a comprehensive overview of dietary intervention trials describing effects of berry anthocyanins on cognitive performance in humans, while also addressing potential underlying mechanisms. A total of 1197 articles were identified through a systematic search, and 49 studies reporting effects on cognitive performance (n = 18), vascular function (n = 22), or cardiometabolic risk markers (n = 32) were included. Significant improvements were observed on memory, while some of the studies also reported effects on attention and psychomotor speed or executive function. Vascular function markers such as brachial artery flow-mediated vasodilation were also affected and consistent evidence was provided for the beneficial effects of berry anthocyanins on endothelial function. Finally, studies reported improvements in blood pressure, but effects on metabolic risk markers (e.g. carbohydrate and lipid metabolism) were less consistent. In conclusion, this review provides evidence for the beneficial effects of berry anthocyanins on cognitive performance as memory improved. Whether observed anthocyanin-induced improvements in vascular function and blood pressure underlie beneficial effects on cognitive performance warrants further study. 相似文献
152.
153.
冯振强 《陶瓷研究与职业教育》2004,2(4):12-13
我们的社会需要的是身心都健康的人才,而目前无论是学校还是家庭,都过多地重视学生的知识掌握和身体训练,忽视对学生健康心理的培养。为此,提出了培养学生健康心理的措施。 相似文献
154.
远红外丙纶的性能研究 总被引:7,自引:2,他引:7
系统测试了采用共混纺丝法研制出的远红外丙纶及织物的物理机械性能、远红外发射性能、保温性能、耐洗涤性能和抗菌性能,并对用远红外丙纶加工的护腿的医疗保健作用进行了临床检测。进而讨论了远红外丙纶及织物的医疗保健作用机理。 相似文献
155.
为探究淮河入海水道二期工程对洪泽湖的泄洪能力以及周边滞洪区的影响,在对研究区河网概化及地形处理的基础上,建立了研究区河网一维、洪泽湖湖区与周边滞洪区二维耦合的水动力数值模型,并采用1991,2003,2006,2007四年实测历史洪水资料对模型进行率定及验证。基于现状工况、规划工况以及不同洪水量级,设计了5个对比方案对研究区进行洪水演进数值模拟,对不同洪水量级进行横向对比,对不同工况进行纵向对比,并对不同方案进行淹没面积分析和洪水影响分析。结果表明,入海水道二期工程的启用可以有效降低洪泽湖水位,提高洪泽湖的防洪标准和周边滞洪区的启用标准,减少同等洪水量级下的受影响人口数和区域GDP,为洪泽湖的防洪安全建设以及周边蓄滞洪区的稳定发展创造了条件。 相似文献
156.
近海大体积混凝土结构所处的外界环境以及地质条件比较复杂,对于带裂缝水闸结构来说,因所处的地理位置、气候变化以及潮汐升降水位等因素的缘故,水闸闸墩裂缝处于张合状态,这降低了水闸结构的稳定性,甚至会影响水闸结构的寿命。沿海环境温度变化对混凝土裂缝宽度变化的实际监测分析,对于混凝土结构安全耐久性评价具有一定价值,依托典型软土地基永定新河防潮闸工程,利用测缝计对闸墩裂缝宽度变化进行健康监测。主要研究运行期环境因素(以空气温度、水温以及潮汐水位为主)对闸墩裂缝的影响,采用健康安全监测软件,通过对数据的挖掘处理,得出环境温度和水位是影响闸墩水下裂缝宽度变化的敏感性因素的结论,为以后水闸闸墩裂缝的安全维护和裂缝的预防提供思路。 相似文献
157.
Geomorphic diversity as a river management tool and its application to the Ganga River,India 总被引:1,自引:0,他引:1
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Understanding of geomorphic processes and the determination of geomorphic diversity in catchments are prerequisites for the sustainable rehabilitation of river systems and for reach‐scale assessment of river health. The Ganga River system in India is a large, complex system consisting of several long tributaries, some >1,000 km, originating from 2 distinct hinterlands—the Himalaya to the north and the cratons to the south. Traversing through a diverse climatic regime across the Plain and through precipitation zones ranging from 600 mm/year near Delhi to 1,200 mm/year in the eastern plains, the Ganga River system has formed very diverse landform assemblages in 3 major geomorphic domains. We have recognized 10 different river classes for the trunk river from Gangotri (source) to Farakka (upstream of its confluence with the Brahmaputra) based on (a) landscape setting, (b) channel and active floodplain properties, and (c) channel planform parameters. The mountainous stretch is characterized by steep valleys and bedrock channels and is dominated by large‐scale sediment production and transport through hill slope processes. The alluvial part of the river is characterized by 8 different river classes of varying reach lengths (60–300 km) many of which show sharp transitions in landscape setting. We have highlighted the application of this approach for the assessment of habitat suitability, environmental flows, and flood risk all of which have been significantly modified during the last few decades due to large‐scale anthropogenic disturbances. We suggest that the diversity embedded in this geomorphic framework can be useful for developing a sustainable river management programme to “work with” the contemporary character and behaviour of rivers. 相似文献
158.
介绍了目前国际上广为采用的5种工程总承包方式以及水泥工业建设项目总包工程合同管理和索赔管理的内容与要求;分析了设计单位进行工程总承包的优势所在;探讨了工程总包实施中各类风险。 相似文献
159.
Gerontechnology acceptance by elderly Hong Kong Chinese: a senior technology acceptance model (STAM)
Ke Chen 《Ergonomics》2014,57(5):635-652
The purpose of this study was to develop and test a senior technology acceptance model (STAM) aimed at understanding the acceptance of gerontechnology by older Hong Kong Chinese people. The proposed STAM extended previous technology acceptance models and theories by adding age-related health and ability characteristics of older people. The proposed STAM was empirically tested using a cross-sectional questionnaire survey with a sample of 1012 seniors aged 55 and over in Hong Kong. The result showed that STAM was strongly supported and could explain 68% of the variance in the use of gerontechnology. For older Hong Kong Chinese, individual attributes, which include age, gender, education, gerontechnology self-efficacy and anxiety, and health and ability characteristics, as well as facilitating conditions explicitly and directly affected technology acceptance. These were better predictors of gerontechnology usage behaviour (UB) than the conventionally used attitudinal factors (usefulness and ease of use).
Practitioner Summary: Previous studies have not given much consideration to age-related health and associated abilities when examining acceptance of technology by the ageing population. By encompassing conventional technology acceptance constructs together with age-related health and ability characteristics, the present study was able to identify more factors affecting gerontechnology acceptance by older Hong Kong Chinese. 相似文献
160.
Lars Fritzsche Jürgen Wegge Martin Schmauder Matthias Kliegel Klaus-Helmut Schmidt 《Ergonomics》2014,57(2):148-161
Prior research suggests that ergonomics work design and mixed teams (in age and gender) may compensate declines in certain abilities of ageing employees. This study investigates simultaneous effects of both team level factors on absenteeism and performance (error rates) over one year in a sample of 56 car assembly teams (N = 623). Results show that age was related to prolonged absenteeism and more mistakes in work planning, but not to overall performance. In comparison, high-physical workload was strongly associated with longer absenteeism and increased error rates. Furthermore, controlling for physical workload, age diversity was related to shorter absenteeism, and the presence of females in the team was associated with shorter absenteeism and better performance. In summary, this study suggests that both ergonomics work design and mixed team composition may compensate age-related productivity risks in manufacturing by maintaining the work ability of older employees and improving job quality. 相似文献