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161.
K. Andrew R. Richards Jennifer M. Jacobs Zachary Wahl-Alexander James D. Ressler 《Journal of Adventure Education & Outdoor Learning》2018,18(4):367-381
Outdoor education (OE) has an increased presence in physical education as it addresses the discipline’s national standards and promotes involvement lifetime physical activity. However, physical educators’ learning to teach OE is not well documented. The purpose of this study was to understand preservice physical educators’ experiences in and perspectives on an OE field experience. Participants included 13 third-year preservice physical educators (10 male, 3 female). Qualitative data were collected using focus group interviews, observations and guided reflections. Results indicated that preservice teachers (PSTs) perceived a controlling course environment that limited educational outcomes. They did, however, increase in confidence teaching OE, and applied skills learned in the teacher education program. With the exception of learning to be more adaptable, however, the PSTs did not perceive the experience as relevant to future teaching. Results are discussed within the framework of occupational socialization theory, and implications for practice are noted. 相似文献
162.
163.
We report an interesting buffer electric relaxation time tuning technique, coupled with a glutaraldehyde cross-linking cell fixation reaction, which allows for sensitive dielectrophoretic analysis and discrimination of bovine red blood cell (bRBC) starvation age. The buffer composition is selected such that two easily accessible dielectrophoretic crossover frequencies (cof) exist. Low concentration glutaraldehyde fixation was observed to produce a threefold decrease in the higher cof with a comparable increase in the lower cof also witnessed. More importantly, increased glutaraldehyde fixation concentration significantly increased the higher cof by a factor found to be sensitive to the bRBC starvation age. 相似文献
164.
Ramona C. Dolscheid-Pommerich Ute Klarmann-Schulz Rupert Conrad Birgit Stoffel-Wagner Berndt Zur 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2016,26(1):82-89
Introduction
Preanalytical specifications for urinalysis must be strictly adhered to avoid false interpretations. Aim of the present study is to examine whether the preanalytical factor ‘time point of analysis’ significantly influences stability of urine samples for urine particle and dipstick analysis.Materials and methods
In 321 pathological spontaneous urine samples, urine dipstick (Urisys™2400, Combur-10-Test™strips, Roche Diagnostics, Mannheim, Germany) and particle analysis (UF-1000 i™, Sysmex, Norderstedt, Germany) were performed within 90 min, 120 min and 240 min after urine collection.Results
For urine particle analysis, a significant increase in conductivity (120 vs. 90 min: P < 0.001, 240 vs. 90 min: P < 0.001) and a significant decrease in WBC (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001), RBC (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001), casts (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001) and epithelial cells (120 vs. 90 min P = 0.610, 240 vs. 90 min P = 0.041) were found. There were no significant changes for bacteria. Regarding urine dipstick analysis, misclassification rates between measurements were significant for pH (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001), leukocytes (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001), nitrite (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001), protein (120 vs. 90 min P < 0.001, 240 vs. 90 min P<0.001), ketone (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001), blood (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001), specific gravity (120 vs. 90 min P < 0.001, 240 vs. 90 min P < 0.001) and urobilinogen (120 vs. 90 min, P = 0.031). Misclassification rates were not significant for glucose and bilirubin.Conclusion
Most parameters critically depend on the time window between sampling and analysis. Our study stresses the importance of adherence to early time points in urinalysis (within 90 min).Key words: urinalysis, automation, analytical sample preparation methods, flow cytometry, specimen handling 相似文献165.
Ingo Schmitt und Stefan Conrad 《Informatik - Forschung und Entwicklung》1999,14(4):218-226
Zusammenfassung. Eine Restrukturierung eines gegebenen Datenbankschemas kann aus unterschiedlichen Gründen notwendig werden. So kann dadurch
z.B. die Verst?ndlichkeit des Schemas verbessert werden. Im Bereich der relationalen Datenbanken steht die Normalisierungstheorie
zur Verfügung, um z.B. Redundanz zu vermeiden. Der Normalisierung liegt dabei ein Begriff der ?quivalenz von Datenbankschemata
zugrunde. Im Bereich der objektorientierten Datenbanken gibt es bislang kaum vergleichbare Ans?tze. In diesem Beitrag pr?sentieren
wir daher einen Ansatz, mit dem Klassenhierarchien in objektorientierten Datenbankschemata in eine „normalisierte” Form transformiert
werden k?nnen. Dazu mu? zun?chst eine extensionale Analyse durchgeführt werden, die die notwendigen Informationen über extensionale
Beziehungen zwischen den gegebenen Klassen liefert. Anschlie?end wenden wir Konzepte der formalen Begriffsanalyse an, um eine
„normalisierte” Klassenhierarchie abzuleiten.
Eingegangen am 16. Januar 1999 / Angenommen am 3. Oktober 1999 相似文献
166.
Kevin T. Mattocks J. Grant Mouser Matthew B. Jessee Samuel L. Buckner Scott J. Dankel Zachary W. Bell 《Journal of sports sciences》2019,37(16):1857-1864
The purpose was to examine changes in the perceptual responses to lifting a very low load (15% one repetition maximum (1RM)) with and without (15/0) different pressures [40% (15/40) and 80% (15/80) arterial occlusion pressure] and compare that to traditional high load (70/0) resistance exercise. Ratings of perceived exertion (RPE) and discomfort were measured following each set of exercise. In addition, resting arterial occlusion pressure was measured prior to exercise. Assessments were made in training sessions 1, 9, and 16 for the upper and lower body. Data are presented as means and 95% CI. There were changes in RPE in the upper body with condition 15/40 [?2.1 (?3.4, ?0.850)] and 15/80 [?2.4 (?3.6, ?1.1)] decreasing by the end of training. In the lower body, RPE decreased in condition 15/40 [?1.4 (?2.3, ?0.431)] by the end of the training study. There was a main effect of time in the upper body with all conditions decreasing discomfort. In the lower body, all conditions decreased except for 15/80. For arterial occlusion pressure, there were differences across time in the 15/40 condition and the 15/80 condition in the upper body. Repeated exposure to blood flow restriction may dampen the perceptual responses over time. 相似文献
167.
Zachary M. Gillen Marni E. Shoemaker Brianna D. McKay Joel T. Cramer 《Research quarterly for exercise and sport》2019,90(2):227-233
Purpose: The purpose of this study was to determine magnitudes of differences for anthropometric and athletic performance scores between high school and elite college-level American football players. Method: Participants included high school-age (n = 3,666) athletes who participated in American football combines, as well as elite college-level (n = 5,537) athletes who participated in the National Football League (NFL) scouting combine. Combine data included position; height; weight; 10-, 20-, and 40-yard dash; pro-agility (PA); L-cone drill (LC); vertical jump (VJ); and broad jump (BJ). Athletes were separated into their respective position group, defensive back (DB), wide receiver (WR), linebacker (LB), quarterback (QB), running back (RB), tight end (TE), defensive line (DL), and offensive line (OL) for analysis of performance differences. Percent differences for each dependent variable were calculated to quantify magnitudes of differences. Results: NFL combine participants scored 3% to 25% better on all measurements, with the largest differences between weight and VJ (14%–25%). Conclusion: The largest measurement-specific differences between high school-age and elite college-level American football players were body size and power. Although it may seem intuitive that elite college-level players would perform better, these data provide a unique perspective to high school players, parents, and coaches, giving new information to use when designing measurement-specific athletic development programs. Thus, strength and conditioning professionals may benefit from emphasizing increases in muscle mass and power output in strength and conditioning programs. 相似文献
168.
The emergence of vibrant research communities of computer scientists in Kenya and Uganda has occurred in the context of neoliberal privatization, commercialization, and transnational capital flows from donors and corporations. We explore how this funding environment configures research culture and research practices, which are conceptualized as two main components of a research community. Data come from a three-year longitudinal study utilizing interview, ethnographic and survey data collected in Nairobi and Kampala. We document how administrators shape research culture by building academic programs and training growing numbers of PhDs, and analyze how this is linked to complicated interactions between political economy, the epistemic nature of computer science and sociocultural factors like entrepreneurial leadership of key actors and distinctive cultures of innovation. In a donor-driven funding environment, research practice involves scientists constructing their own localized research priorities by adopting distinctive professional identities and creatively structuring projects. The neoliberal political economic context thus clearly influenced research communities, but did not debilitate computing research capacity nor leave researchers without any agency to carry out research programs. The cases illustrate how sites of knowledge production in Africa can gain some measure of research autonomy, some degree of global competency in a central arena of scientific and technological activity, and some expression of their regional cultural priorities and aspirations. Furthermore, the cases suggest that social analysts must balance structure with culture, place and agency in their approaches to understanding how funding and political economy shape scientific knowledge. 相似文献
169.
170.
Nicholas De Witt Edmund King Jean vanden Bossche A. Harry Passow Eve Malmquist Alfred Yates Urban Dahllöf John D. Williams Conrad Graham Rudolf Cohen Elfriede Höhn Anna -Liisa Sysiharju Harry D. Gideonse D. J. D. Smith S. Kaneti-Barry Werner H. Tack M. J. Langeveld 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1964,10(3):358-382