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This article is the third in a series reporting on the changes in attitudes and interests‐‐mainly with respect to physics‐of several hundred students as they proceed through the Danish upper secondary school (Gymnasium). It concentrates on the results of the final investigation which took place shortly before the students leave the school. 相似文献
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N. N. Rossing A. B. Nielsen A.-M. Elbe D. S. Karbing 《European Journal of Sport Science》2016,16(2):237-245
The primary purpose of this study was to investigate the effect of the place of early development in a sample of Danish male elite and youth handball and football players. The sample included 366 handball and football players from the elite Danish league in the season 2011–2012 and a comparison sample of youth players under the age of 12 from 2003, including 147,221 football and 26,290 handball players. Odds ratio analysis showed that both population size and density significantly affected the proportional number of youth players per community and the odds of athletes reaching an elite level in football and handball. The odds for youth player registrations in both handball and football increased in rural in contrast to urban communities. However, elite football players primarily came from communities of high density (>1000 pop./km2), whereas elite handball players primarily came from less densely populated communities (100 to <250 pop./km2). Furthermore, there seems to be a relation between representation of elite and talent clubs in different communities and the probability of becoming an elite player in both sports. The limited number of elite players in both sports from rural communities may be due to national talent development strategies that do not incorporate development support for clubs in rural areas. Additionally, the results of the study clearly suggest the need to include the youth player population to advance research findings in birthplace effect studies. 相似文献
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M. Skolimowski M. Weiss Nielsen F. Abeille P. Skafte-Pedersen D. Sabourin A. Fercher D. Papkovsky S. Molin R. Taboryski C. Sternberg M. Dufva O. Geschke J. Emnéus 《Biomicrofluidics》2012,6(3)
A modular microfluidic airways model system that can simulate the changes in oxygen tension in different compartments of the cystic fibrosis (CF) airways was designed, developed, and tested. The fully reconfigurable system composed of modules with different functionalities: multichannel peristaltic pumps, bubble traps, gas exchange chip, and cell culture chambers. We have successfully applied this system for studying the antibiotic therapy of Pseudomonas aeruginosa, the bacteria mainly responsible for morbidity and mortality in cystic fibrosis, in different oxygen environments. Furthermore, we have mimicked the bacterial reinoculation of the aerobic compartments (lower respiratory tract) from the anaerobic compartments (cystic fibrosis sinuses) following an antibiotic treatment. This effect is hypothesised as the one on the main reasons for recurrent lung infections in cystic fibrosis patients. 相似文献
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Volianitis S Dawson EA Dalsgaard M Yoshiga C Clemmesen J Secher NH Olsen N Nielsen HB 《Journal of sports sciences》2012,30(2):149-153
Reduced hepatic lactate elimination initiates blood lactate accumulation during incremental exercise. In this study, we wished to determine whether renal lactate elimination contributes to the initiation of blood lactate accumulation. The renal arterial-to-venous (a-v) lactate difference was determined in nine men during sodium lactate infusion to enhance the evaluation (0.5 mol x L(-1) at 16 ± 1 mL x min(-1); mean ± s) both at rest and during cycling exercise (heart rate 139 ± 5 beats x min(-1)). The renal release of erythropoietin was used to detect kidney tissue ischaemia. At rest, the a-v O(2) (CaO(2)-CvO(2)) and lactate concentration differences were 0.8 ± 0.2 and 0.02 ± 0.02 mmol x L(-1), respectively. During exercise, arterial lactate and CaO(2)-CvO(2) increased to 7.1 ± 1.1 and 2.6 ± 0.8 mmol x L(-1), respectively (P < 0.05), indicating a -70% reduction of renal blood flow with no significant change in the renal venous erythropoietin concentration (0.8 ± 1.4 U x L(-1)). The a-v lactate concentration difference increased to 0.5 ± 0.8 mmol x L(-1), indicating similar lactate elimination as at rest. In conclusion, a -70% reduction in renal blood flow does not provoke critical renal ischaemia, and renal lactate elimination is maintained. Thus, kidney lactate elimination is unlikely to contribute to the initial blood lactate accumulation during progressive exercise. 相似文献
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S.S. Nielsen 《Journal of Food Science Education》2004,3(2):21-25
ABSTRACT: Two of the challenges in teaching Food Analysis are bringing relevance to the various chemical and physical analyses discussed and exposing students to the realities of quality assurance in the food industry. In a project to help meet those objectives, each student, with the assistance of a "resource person" from the food industry, completes the project as if he or she is responsible for the quality assurance analyses of a specific food product in a food company. The student identifies the chemical, physical, sensory, and microbial analyses for raw ingredients, in-process products, and the finished product. The project requires the student to participate in related class discussion, prepare a final written report, and make a brief class presentation. Analysis of survey data showed the project was more than moderately relevant or useful to former students working in the food industry, and related directly to the initial or current positions of most former students. 相似文献