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This study aimed to describe the effect of compression garments on middle cerebral artery blood flow velocity (MCAv) in relation to cognitive and exercise performance whilst cycling. In a randomised-controlled-cross-over design, 15 well-trained male cyclists were recruited to participate in three identical trials wearing loose fitting shorts (control), low-grade, or medium-grade compression garments. The protocol involved four 8?min increments of cycling at 30%, 50%, 70%, and 85% maximal power output and a 4?km time-trial. Participants undertook a cognitive Stroop task at baseline and at the midpoint of each increment. MCAv was monitored with Transcranial Doppler Ultrasonography. Mean arterial pressure (MAP) and partial pressure of end-tidal CO2 (PetCO2) were measured throughout. MCAv, MAP, PetCO2, and reaction time of the complex Stroop task were influenced by exercise intensity, but not compression garments. Compression garments significantly affected cognitive accuracy in the complex Stroop task such that low-grade compression appeared to enhance cognitive accuracy in comparison to the control condition at the highest intensity (p?=?.010). Time-trial performance did not differ between the control (338.0?±?17.3 s), low-grade (338.7?±?18.7 s), or medium-grade (342.2?±?19.3 s) conditions (p?=?.114). Compression garments did not affect MCAv during exercise or time-trial performance, but compression may be beneficial for improved cognitive accuracy during high-intensity exercise. Further research is required to elucidate the potential impact on cognitive performance.  相似文献   
74.
The essential demographic data and related information for India is provided specifically for the publishing industry. The focus has been placed on the economics, education and computer industry in relation to the complex cultural factors of different languages and religions. The role of India in relation to the other three BRIC countries or Brazil, China and Russia is explored.  相似文献   
75.
Census information of some form has been collected in Canada since the 1611 census of New France. Aboriginal people, identified or not, have been included in these enumerations. The collection of this information has had a profound impact on Aboriginal people and has been an element that has shaped their relationship with the dominant society. In response, Canadian Aboriginal people have often resisted and refused to co-operate with census takers and their masters. This article is an examination of this phenomenon focused on the censuses conducted in the post-Confederation period to the present. A census is made to collect information on populations and individuals that can then be used to configure and shape social and political relations between those being enumerated and the creators of the census. However, the human objects of the census are not just passive integers and they have resisted its creation in a number of ways, including being “missing” when the census is taken, refusing to answer the questions posed by enumerators or even driving them off Aboriginal territory. A census identifies elements of the social order and attempts to set them in their “proper” place and those who do not wish to be part of that order may refuse to take part. Archivists and historians must understand that the knowledge gained in a census is bound with the conditions of own creation. This has been noted by contemporary Aboriginal researchers who often state that the archival record of their people often distorts history and reflects the ideas and superficial observations of their Euro-Canadian creators. Changes to the Census of Canada since 1981, have increased the participation rate and therefore changed the nature of the record.
Brian Edward HubnerEmail:

Brian Edward Hubner   is currently Acquisition and Access Archivist at the University of Manitoba Archives & Special Collections. He was previously employed at the Archives of Manitoba, in Government Records; Queen’s University Archives, Kingston; and at the National Archives of Canada, Ottawa. He has a Master of Arts (History, in Archival Studies) from the University of Manitoba, and a Master of Arts (History), from the University of Saskatchewan. The 2nd edition of Brian’s co-authored book on the history of the Cypress Hills of Saskatchewan and Alberta is being published in 2007. He has published articles and delivered conference papers on Canadian Aboriginal peoples including “Horse Stealing and the Borderline: The N.W.M.P. and the Control of Indian Movement, 1874-1900.” His current research interest focuses on relationship between Canada’s Aboriginal Peoples and Canadian archives. Brian is married and has two children.  相似文献   
76.
The retrieval of sentences that are relevant to a given information need is a challenging passage retrieval task. In this context, the well-known vocabulary mismatch problem arises severely because of the fine granularity of the task. Short queries, which are usually the rule rather than the exception, aggravate the problem. Consequently, effective sentence retrieval methods tend to apply some form of query expansion, usually based on pseudo-relevance feedback. Nevertheless, there are no extensive studies comparing different statistical expansion strategies for sentence retrieval. In this work we study thoroughly the effect of distinct statistical expansion methods on sentence retrieval. We start from a set of retrieved documents in which relevant sentences have to be found. In our experiments different term selection strategies are evaluated and we provide empirical evidence to show that expansion before sentence retrieval yields competitive performance. This is particularly novel because expansion for sentence retrieval is often done after sentence retrieval (i.e. expansion terms are mined from a ranked set of sentences) and there are no comparative results available between both types of expansion. Furthermore, this comparison is particularly valuable because there are important implications in time efficiency. We also carefully analyze expansion on weak and strong queries and demonstrate clearly that expanding queries before sentence retrieval is not only more convenient for efficiency purposes, but also more effective when handling poor queries.  相似文献   
77.
Recordkeeping in twentieth century colonial states has been ignored by scholars, or at best regarded as the result of a monolithic process of migration of metropolitan practices. Registries provided the principal organ of recordkeeping in British government systems of administration. This comparative study of the registries in the neighbouring territories of Northern Rhodesia (now Zambia) and Nyasaland (now Malawi) reveals the true extent of metropolitan British influence, exposing an absence of centralised advice, and a consequent dependence upon individual innovation. This engendered divergent and sometimes weak recordkeeping regimes. The effects of this included the diminution of fiduciary responsibility and administrative accountability.  相似文献   
78.
Forecasts indicate a growing demand for digital content around the world. Converting to digital content can open up countless new revenue possibilities. Adding alternate channels may be worth consideration, but what are the options and what does it take to utilize them effectively? This article explores the opportunities that potentially exist for publishers with content that may be digitized and distributed to global markets. A brief review of the current marketplace is also incorporated, including current players and trends. Finally, an analysis of some of the potential issues, challenges and pitfalls is presented in context of delving into a new international digital content distribution strategy.  相似文献   
79.
Teacher education issues are high on the policy agenda across Europe. The United Nations Convention on the Rights of People with Disabilities (2006) is gaining momentum and providing a force for change, supported by many communications both internationally and at European level that recognize how central education is in efforts to develop a more equitable society. In moving towards a more inclusive education system, there is a need to train all teachers to meet the diverse needs of all learners in their classrooms and to work collaboratively with colleagues. Drawing on key documents, this article outlines the policy context and reviews the available evidence supporting the move towards teacher education for inclusion across Europe. It presents the work of the European Agency for Development in Special Needs Education, to highlight some of the opportunities and challenges within its member countries in addressing teacher education for inclusion.  相似文献   
80.
Abstract

The advent of the Internet alleviates the access bottleneck to TV distribution channels and softens licensing requirements. This lowers entry barriers to TV markets via the Internet in various forms. This paper takes the German TV sector as an example to analyse the attractiveness of TV markets for new entrants. A sequential framework for entering TV markets is introduced. The skills set of an Internet‐based TV provider for such an entry is examined. Technical feasibility, legal aspects, and potential sources of revenue are considered.

Potential above average profits due to the market's oligopolistic structure, as well as an increased contestability thanks to lower market entry barriers seem to render the German TV market attractive for new entrants. In early 2002, Internet‐based TV still faced severe technical and legal constraints. The analysis suggests that once these constraints have been overcome, the Internet could be an attractive additional distribution channel for some types of television content. While existing revenue sources from the TV sector are expected to be transferable to a certain degree, the value of innovative revenue sources based on online sales cannot yet be determined. This value will depend on the future acceptance of interactivity by the viewer (e. g. Owen 1999).  相似文献   
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