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141.
Roberto Carlos dos Santos Pacheco Vinícius Medina Kern Paulo Henrique S. Bermejo 《International Information and Library Review》2003,35(2-4):319
Cooperative organization has been proposed as a means to improve the usefulness of virtual libraries. Information interchange among library and other academic applications is often hindered by the lack of application interoperability. This hindrance may be overcome through the development of standards that allow for digital libraries to exchange and share information with other applications. The Graduate Program in Production Engineering (PPGEP) of the Federal University of Santa Catarina (UFSC) launched its Theses and Dissertations Bank (BTD) in 1995. BTD is possibly the first online academic digital library of theses. From a digital document repository, BTD evolved into a system that combines bibliometry and informetry features. BTD is used by students and faculty in their research activities, but also by decision makers from industry and academia. They use it, respectively, to search for specialists and to measure interest and knowledge interchange among PPGEP research areas. This article presents the history, features, and development prospects for the BTD project. The integration of BTD with other academic applications, especially those of the Brazilian national science and technology platform, is emphasized. 相似文献
142.
143.
William A. Lucas Robert K. Yin Fred B. Wood Walter S. Baer Michael Botein Leland L. Johnson 《Communication Booknotes Quarterly》2013,44(11):2-4
William A. Lucas and Robert K. Yin's Serving Local Needs with Telecommunications (Santa Monica, Calif: Rand Corporation Report R-1345-MF, November 1973—$3.00, paper). Fred B. Wood's The Potential for Congressional Use of Emergent Telecommunications: An Exploratory Assessment (Washington, D.C.: George Washington University, Program of Policy Studies in Science and Technology, May 1974—apparently free on request) Walter S. Baer, Michael Botein, Leland L. Johnson, Carl Pilnick, Monroe E. Price, and Robert K. Yin's Cable Television: Franchising Considerations (New York: Crane, Russak, & Co., 1974-=T13.50) Charles G. Woodard's Cable Television: Acquisition and Operation of CATV Systems (New York: McGraw-Hill, 1974—$27.50) Planning Interconnection Systems: Options for the Twin Cities Metropolitan Area (Washington, D.C.: Cable Television Information Center, 2100 M St. N.W., 1974-47.50, paper) Cablelines (Cable Communications Resource Center, 1900 L St., N.W., Washington, D.C. 20036—monthly/free on request) 相似文献
144.
This study examined underground iron ore miners' occupational narratives to uncover how their stories socialize miners into blue-collar careers and reinforce their work identities. Through the root theme of sisu (Finnish for inner determination), underground miners create a status hierarchy that is used to construct a sense of pride around their work and to establish milestones of success for themselves and others in their workgroup. Furthermore, they communicatively construct exemplars that guide their performance and decisions during the unfolding of their work experiences. Their discourses provide alternatives to white-collar conceptualizations and practices of careers and success. 相似文献
145.
Paula Clara Santos Sandra Abreu Carla Moreira Diana Lopes Rute Santos Odete Alves 《Journal of sports sciences》2013,31(14):1398-1408
AbstractThe aims of the this prospective study were to analyse physical activity (PA) engagement during the first and second trimesters, considering the different guidelines published on PA, to document the individual characteristics associated with the accomplishment of these guidelines and to examine pregnant women’s perceived barriers to leisure PA, using a socioecological framework. A sample of 133 pregnant women in two stages – at 10–12 weeks’ gestation (T1) and 20–22 weeks’ gestation (T2) – were evaluated. PA was assessed by accelerometry during the T1 and T2 evaluation stages. Socio-demographic characteristics, lifestyle factors and barriers to leisure PA were assessed via questionnaire. A large proportion of women (ranging from 32% to 96%) did not reach the levels of PA recommended by the guidelines. There were no significant differences between T1 and T2 with regard to compliance with PA recommendations. A decrease in PA levels from T1 to T2 was noted for all recommendations. No associations were found between participants’ characteristics and adherence to the recommendations in T1 and T2. No significant differences were found in barriers to leisure PA between T1 and T2. The most commonly reported barriers to leisure PA were intrapersonal, not health related. Our results indicate that there were no differences between trimesters regarding compliance of PA recommendations, and perceived barriers were similar in both trimesters. 相似文献
146.
Diana A. Santos Adilson Marques Cláudia S. Minderico Ulf Ekelund 《Journal of sports sciences》2018,36(15):1720-1726
Cardiorespiratory fitness (CRF) is associated with health benefits in children, improving cardiac morphology, cardiovascular disease risk factors, and biological outcomes. This study aimed to examine the substitution effects of displaying a fixed duration of sedentary time with a fixed duration of physical activity (PA) at different intensities on children’s CRF. A total of 315 children (136 boys) were assessed (age: 10.6 ± 0.6 years old). Outcomes at baseline and follow-up (16-months) were CRF determined using a maximal cycle test and sedentary time and PA measured with accelerometers. Data were analysed by isotemporal substitution analyses estimating the effect of reallocating 30 min/day of sedentary time by light (LPA), moderate (MPA) and vigorous physical activity (VPA) on CRF. VPA was positively and significantly associated with CRF cross-sectional (β = 0.026, p < 0.001) and prospectively (β = 0.010, p < 0.001). Reallocating 30 min/day of sedentary time into VPA was positively cross-sectionally (β = 0.780, p < 0.001) and prospectively (β = 0.303, p < 0.05) associated with CRF. Conversely, relocating 30-minutes of sedentary time into 30 minutes of LPA and MPA was not associated with CRF. These results suggest that reallocating an equal amount of time from sedentary into VPA is cross-sectional and prospectively associated with a favourable CRF. 相似文献
147.
148.
Drawing upon the concepts of civic epistemologies and sociotechnical imaginaries, this article delves into the history of nuclear energy in Portugal, analyzing the ways in which the nuclear endeavor was differently enacted by various sociopolitical collectives – the Fascist State, post-revolutionary governments and the public. Following the 1974 revolution - known as the Carnation Revolution - this paper analyzes how the nuclear project was fiercely contested by a vibrant anti-nuclear movement assembled against the construction of the Ferrel Nuclear Plant, the first sociotechnical controversy in Portugal, paving the way for the emergence of a combative civic epistemology. Supported by semi-structured interviews with scientists, activists and local residents of Ferrel and the analysis of historical material, this article presents the failed Portuguese nuclear endeavor as an emblematic case study to explore the co-production of science and society, in particular the role of revolutionary processes in the unfolding of sociotechnical controversies. 相似文献
149.
Lucas SJ Anglem N Roberts WS Anson JG Palmer CD Walker RJ Cook CJ Cotter JD 《Journal of sports sciences》2008,26(5):477-489
The aim of this study was to determine the magnitude and pattern of intensity, and physiological strain, of competitive exercise performed across several days, as in adventure racing. Data were obtained from three teams of four athletes (7 males, 5 females; mean age 36 years, s = 11; cycling .VO(2 peak) 53.9 ml . kg(-1) . min(-1), s = 6.3) in an international race (2003 Southern Traverse; 96 - 116 h). Heart rates (HR) averaged 64% (95% confidence interval: +/- 4%) of heart rate range [%HRR = (HR - HR(min))/(HR(max) - HR(min)) x 100] during the first 12 h of racing, fell to 41% (+/-4%) by 24 h, and remained so thereafter. The level and pattern of heart rate were similar across teams, despite one leading and one trailing all other teams. Core temperature remained between 36.0 and 39.2 degrees C despite widely varying thermal stress. Venous samples, obtained before, during, and after the race, revealed increased neutrophil, monocyte and lymphocyte concentrations (P < 0.01), and increased plasma volume (25 +/- 10%; P < 0.01) with a stable sodium concentration. Standardized exercise tests, performed pre and post race, showed little change in the heart rate-work rate relationship (P = 0.53), but a higher perception of effort post race (P < 0.01). These results provide the first comprehensive report of physiological strain associated with adventure racing. 相似文献
150.