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41.
This study assessed the associations between these factors in a random sample of Czech families with preschool and school-aged children. A nationally representative sample comprised 185 families with preschool children and 649 families with school-aged children (dyads; both parents and child n?=?365, mother and child n?=?730, and father and child n?=?469). The participants wore Yamax Digiwalker SW-200 pedometers at least four weekdays and both weekend days and completed family logbooks (anthropometric parameters, daily step counts (SC), and screen time (ST)). When a parent (fathers at weekends and mothers both on weekdays and at weekends) achieved 10,000 SC per day, their children were also significantly (OR?=?2.93–6.06, 95% CI?=?2.02–9.26) more likely to meet the daily SC recommendation. On the contrary, the involvement of fathers in organized leisure-time PA reduced their children's odds of meeting the SC recommendation on weekdays (OR?=?0.53, 95% CI?=?0.31–0.89) and at weekends (OR?=?0.41, 95% CI?=?0.24–0.72). The excessive ST of parents at weekends reduced the odds of their children meeting the SC recommendation (mother–child dyads: OR?=?0.44, 95% CI?=?0.26–0.72; father–child dyads: OR?=?0.63, 95% CI?=?0.37–1.06). High levels of parents’ PA contribute to the achievement of the recommended daily PA in children on weekdays and at weekends. Excessive weekend ST of parents reduces their odds of their children achieving the recommended daily PA; however, the influence of parents’ PA on their children’s achieving the recommended daily PA is stronger than the inhibitory effect of ST.  相似文献   
42.
We present a novel 3D hybrid assembly of a polymer microfluidic chip with polycarbonate track-etched membrane (PCTEM) enabling membrane-supported cell culture. Two chip designs have been developed to establish either diffusive or convective reagent delivery using the integrated PCTEM. While it is well suited to a range of cell-based assays, we specifically employ this platform for the screening of a common antitumor chemotoxic agent (mitomycin C – MMC) on the HL60 myeloid leukemia cell line. The toxic activity of MMC is based on the generation of severe DNA damage in the cells. Using either mode of operation, the HL60 cells were cultured on-chip before, during, and after exposure to MMC at concentrations ranging from 0 to 50 μM. Cell viability was analysed off-chip by the trypan blue dye exclusion assay. The results of the on-chip viability assay were found to be consistent with those obtained off-chip and indicated ca. 40% cell survival at MMC concentration of 50 μM. The catalogue of capabilities of the here described cell assay platform comprises of (i) the culturing of cells either under shear-free conditions or under induced through-membrane flows, (ii) the tight time control of the reagent exposure, (iii) the straightforward assembly of devices, (iv) the flexibility on the choice of the membrane, and, prospectively, (v) the amenability for large-scale parallelization.  相似文献   
43.
To examine the activity profile and physiological demands of top-class soccer refereeing, we performed computerized time-motion analyses and measured the heart rate and blood lactate concentration of 27 referees during 43 competitive matches in the two top Danish leagues. To relate match performance to physical capacity and training, several physiological tests were performed before and after intermittent exercise training. Total distance covered was 10.07 - 0.13 km (mean - s x ), of which 1.67 - 0.08 km was high-intensity running. High-intensity running and backwards running decreased (P ? 0.05) in the second half. Mean heart rate was 162 - 2 beats· min -1 (85 - 1% of maximal heart rate) and the mean blood lactate concentration was 4.9 - 0.3 (range 1.7-14.0) mmol·l -1 . The amount of high-intensity running during a match was related to the Yo-Yo intermittent recovery test ( r 2 = 0.57; P ? 0.05) and the 12 min run ( r 2 = 0.21; P ? 0.05). After intermittent training ( n = 8), distance covered during high-intensity running was greater (2.06 - 0.13 vs 1.69 - 0.08 km; P ? 0.05) and mean heart rate was lower (159 - 1 vs 164 - 2 beats· min -1 ; P ? 0.05) than before training. The results of the present study demonstrate that: (1) top-class soccer referees have significant aerobic energy expenditure throughout a game and episodes of considerable anaerobic energy turnover; (2) the ability to perform high-intensity running is reduced towards the end of matches; (3) the Yo-Yo intermittent recovery test can be used to evaluate referees' match performance; and (4) intense intermittent exercise training improves referees' performance capacity during a game.  相似文献   
44.
This article examines the content and methodology of studies on Tai Chi as a sport in health care. We investigate the concept behind the rather simple name “Tai Chi,” concluding that this concept is manifold and highly variable. How did researchers deal with this variability when studying the effects of Tai Chi as a health-care intervention? We then explore how scientific research on Tai Chi has been conducted to date and draw the interim conclusion that the variability was barely taken into consideration. Our analysis of seven Tai Chi interventions reveals that two interventions referred to as Tai Chi may differ considerably in their content. The variability poses difficulty in repeating the intervention and drawing causal inferences. This problem is discussed in the current literature under the term “complexity in health-care interventions.” On the basis of a summary of this debate, we discuss the challenge of researching Tai Chi from a complex perspective—with the aim of achieving solid results that can be repeated.  相似文献   
45.
Ciliary neurotrophic factor (CNTF) has pleiotropic actions on many neuronal populations as well as on glia. Signal transduction by CNTF requires that it bind first to CNTF-R, permitting the recruitment of gp130 and LIF-R, forming a tripartite receptor complex. Cells that only express gp130 and LIF-R, but not CNTF-R are refractory to stimulation by CNTF. On many target cells CNTF only acts in the presence of its specific agonistic soluble receptors. We engineered a soluble fusion protein by linking the COOH-terminus of sCNTF-R to the NH2-terminus of CNTF. Recombinant CNTF/sCNTF-R fusion protein (Hyper-CNTF) was successfully expressed in COS-7 cells. The apparent molecular mass of the Hyper-CNTF protein was estimated from western blots to be 75 kDa. Proliferation assays of transfected BAF/3 cells in response to CNTF and Hyper-CNTF were used to verify the activity of the cytokines. The proliferative results confirmed that CNTF required homodimerization of the gp130, CNTF-R and LIF-R receptor subunit whereas Hyper-CNTF required heterodimerization of the gp130 and LIF-R receptor subunit. We concluded that the fusion protein Hyper-CNTF had superagonistic activity on target cells expressing gp130 and LIF-R, but lacking membrane-bound CNTF-R. Project supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholar, Zhejiang Province, China and SFB415, TP B5, Germany.  相似文献   
46.
47.
This paper examines the relationship between social background, choice of university programme and academic culture among Danish university students. Statistically and sociologically, university students are often treated as a homogeneous group, but the ever-increasing number of students in higher education demands a closer examination of the hidden heterogeneity in the students’ social origin and educational strategies. Using a mixed-method approach (register data and ethnographic observations and interviews) the paper focuses on the students’ class origins and on different cultural practices in three Danish university programmes. It is shown that the Danish university field is characterized by a significant variation in social selectivity from programme to programme, and it is argued that these different social profiles correspond with distinctively different cultural practices in the programmes. Correspondingly, the students have distinctively different strategies towards education and future work life.  相似文献   
48.
Gläser  Jochen  Ash  Mitchell  Buenstorf  Guido  Hopf  David  Hubenschmid  Lara  Janßen  Melike  Laudel  Grit  Schimank  Uwe  Stoll  Marlene  Wilholt  Torsten  Zechlin  Lothar  Lieb  Klaus 《Minerva》2022,60(1):105-138
Minerva - The independence of research is a key strategic issue of modern societies. Dealing with it appropriately poses legal, economic, political, social and cultural problems for society, which...  相似文献   
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50.
With the proliferation of personal computers in the home and in the workplace, there is an ever increasing demand for the integration of computers into the curricula of educational institutions. Invariably, the approach taken to satisfying such demands involves the training of the current staff of educators in the use of personal computers as both a teaching and a research and administrative tool. This article will look at the educator's anxiety prior to training on the computer, and the changes in attitude brought about by continuous exposure to the computer in a classroom setting.  相似文献   
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