The energetics and benefit of an arm swing in submaximal and maximal vertical jump performance     

Lees A  Vanrenterghem J  De Clercq D 《Journal of sports sciences》2006,24(1):51-57

The aims of this study were to investigate the energy build-up and dissipation mechanisms associated with using an arm swing in submaximal and maximal vertical jumping and to establish the energy benefit of this arm swing. Twenty adult males were asked to perform a series of submaximal and maximal vertical jumps while using an arm swing. Force, motion and electromyographic data were recorded during each performance and used to compute a range of kinematic and kinetic variables, including ankle, knee, hip, shoulder and elbow joint powers and work done. It was found that the energy benefit of using an arm swing appears to be closely related to the maximum kinetic energy of the arms during their downswing, and increases as jump height increases. As jump height increases, energy in the arms is built up by a greater range of motion at the shoulder and greater effort of the shoulder and elbow muscles but, as jump height approaches maximum, these sources are supplemented by energy supplied by the trunk due to its earlier extension in the movement. The kinetic energy developed by the arms is used to increase their potential energy at take-off but also to store and return energy from the lower limbs and to "pull" on the rest of the body. These latter two mechanisms become more important as jump height increases with the pull being the more important of the two. We conclude that an arm swing contributes to jump performance in submaximal as well as maximal jumping but the energy generation and dissipation sources change as performance approaches maximum.  相似文献   

European perspectives on men and masculinities,by Jeff Hearn and Keith Pringle with members of CROME (Critical Research on Men in Europe)     

Anna C. Hickey‐Moody 《Gender and education》2009,21(2):235-236

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The scientist's code     

André Cournand  Michael Meyer 《Minerva》1976,14(1):79-96

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Museums at the crossroad: Contributing to dialogue, curiosity and wonder in natural history museums     

Antonio G. Valdecasas  Virginia Correia  Ana M. Correas 《Museum Management and Curatorship》2006,21(1):32-43

The first natural history collections opened to the public were inspired by a sense of curiosity and wonder about the products of nature. They were ‘cabinets of curiosities’ that offered a first-hand interaction between owner and visitors. Nowadays, these two facets of the museum experience—dialogue and wonder—have been lost, in part, due to the information overload coming via the media and the impersonal nature of the museum visit. This paper offers some reflections on the evolution of the museum visit, suggests some ways to rediscover this ‘sense of wonder’ and provides ideas on how to promote two-way communication with museum visitors. Two examples of exhibitions are offered as illustrations of the points discussed.  相似文献   

Benchmarking scientific journals from the submitting author's viewpoint     

Bo‐Christer Bjrk  Jonas Holmstrm 《Learned Publishing》2006,19(2):147-155

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Buddhist Wall Paintings at Nako Monastery,North India: Changing of the Technology Throughout Centuries     

Tatjana Bayerová 《文物保护研究》2018,63(3):171-188

The technical study of wall paintings from the Buddhist temple complex at Nako, Western Himalayas, was one of the basic preconditions required for designing an appropriate conservation strategy. The complex, composed of four temples from the eleventh–twelfth century, offered a unique possibility to carry out a comprehensive research of technology and painting materials used in early and later western Tibetan Buddhist wall paintings as well as a comparative assessment with murals from other sites in the Western Himalayas. The study was based on extensive fieldwork and an integrated analytical approach comprising a wide range of non-destructive and micro-destructive methods. Answering the question of the coevality of paintings in the smaller temples with other original murals, the precise characterisation of binding media, the detection of the yellow dye gamboge and natural minerals posnjakite and brochantite identified for the first time in Himalayan murals, the clarification of technology of metal decoration, and the making of raised elements are some of the most exciting results which emerged from the research.  相似文献   

Picture it in your mind: generating high level visual representations from textual descriptions     

Fabio?Carrara  Andrea?EsuliEmail authorView author&#;s OrcID profile  Tiziano?Fagni  Fabrizio?Falchi  Alejandro?Moreo Fernández 《Information Retrieval》2018,21(2-3):208-229

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Health science libraries in Sweden: new directions,expanding roles          下载免费PDF全文

Lotta Haglund  Annikki Roos  Petra Wallgren‐Björk 《Health information and libraries journal》2018,35(3):251-255

Librarians in Sweden are facing huge challenges in meeting the demands of their organisations and users. This article looks at four key areas: coping with open science/open access initiatives; increasing demands from researchers for support doing systematic reviews; understanding user experiences in Swedish health science libraries; and the consequences of expanding roles for recruitment and continuing professional development. With regard to changing roles, there is an increasing shift from the generalist towards the expert role. The authors raise the issue as to how to prepare those new to the profession to the changing environment of health science libraries.  相似文献   

Intercultural Communication and the Central States Region     

Alberto González 《Communication Studies》2018,69(4):362-365

This reflection essay describes the Central States Region as an area rich in intercultural communication. González describes Mexican American migrant farmworker organizing as an intercultural activity since the union activists attempted to influence both Mexican heritage and European heritage audiences. González also describes the many interculturalists working in the Midwest who influenced his early research.  相似文献   

Spanish historic archives’ use of websites as a management transparency vehicle     

Ana R. Pacios  José Luis La Torre Merino 《Archival Science》2018,18(2):185-205

Against the backdrop of Spain’s Transparency Act, this article discusses the presence or otherwise of a series of document types, proposed as management-related transparency indicators, on 61 (8 national and 53 provincial) historic archive websites. Although examples of good practice were identified, the information provided was found to be scant, in particular as regards lines of action, organisational objectives and yearly reports. The information most commonly provided on the websites included the collection classification chart, service use regulations and citizen charters. The inference drawn was that archives, so intently focused on their role in the application of the Act by the organisations they serve, neglect their own administrative obligations in respect of its provisions. The recommendation is that as government-funded and subsidised public service institutions, historic archives should exercise transparency by furnishing the information stipulated in the Act on their websites.  相似文献