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71.
Marcus P. Hannon Daniel J. Carney Stephen Floyd Lloyd J. F. Parker John McKeown Barry Drust 《Journal of sports sciences》2020,38(11-12):1326-1334
ABSTRACT For the first time we aimed to: (1) assess fat-free mass (FFM) and RMR in youth soccer players, (2) compare measured RMR to estimated RMR using previously published prediction equations, and (3) develop a novel population-specific prediction equation. In a cross-sectional design, 99 males from a Premier League academy underwent assessments of body composition (DXA) and RMR (indirect-calorimetry). Measured RMR was compared to estimated values from five prediction equations. A novel RMR prediction equation was developed using stepwise multiple regression. FFM increased (P<0.05) between U12 (31.6±4.2 kg) and U16 (56.3±5.3 kg) after which no further increases occurred (P>0.05). RMR in the U12s (1655±195 kcal.day?1), U13s (1720±205 kcal.day?1) and U14s (1846±218kcal.day?1) was significantly lower than the U15s (1957±128 kcal.day?1), U16s (2042±155 kcal.day?1), U18s (1875±180 kcal.day?1) and U23s (1941±197 kcal.day?1) squads (P>0.05). FFM was the single best predictor of RMR (r2=0.43; P<0.01) and was subsequently included in the novel prediction equation: RMR (kcal.day?1) = 1315 + (11.1 x FFM in kg). Both FFM and RMR increase from 12-16 years old, thus highlighting the requirement to adjust daily energy intake to support growth and maturation. The novel prediction RMR equation developed may help to inform daily energy requirements. 相似文献
72.
This study reports an intervention to initiate environmental learning and facilitate pro-environmental behaviour. The purpose was to examine the impact of ambient learning displays on energy consumption and conservation at the workplace, more specifically the evaluation of learning outcome and behaviour change. Using a quasi-experimental design, the empirical study was conducted among employees working at a university campus. For the experimental treatments, ambient learning display prototypes were varied on two design dimensions, namely representational fidelity and notification level. The results do not provide clear evidence that the design of the displays influences learning outcome or that the displays lead to pro-environmental behaviour change. Nevertheless, the sole deployment of the display prototypes eased the comprehension of the information provided and lowered the need for additional information. Thus, ambient learning displays provide a promising framework in the context of environmental learning and beyond. 相似文献
73.
Marcus Lehmann Alison M. Wallbank Kimberly A. Dennis Adam R. Wufsus Kara M. Davis Kuldeepsinh Rana Keith B. Neeves 《Biomicrofluidics》2015,9(6)
In vitro assays of platelet function and coagulation are typically performed in the presence of an anticoagulant. The divalent cation chelator sodium citrate is among the most common because its effect on coagulation is reversible upon reintroduction of divalent cations. Adding divalent cations into citrated blood by batch mixing leads to platelet activation and initiation of coagulation after several minutes, thus limiting the time blood can be used before spontaneously clotting. In this work, we describe a herringbone microfluidic mixer to continuously introduce divalent cations into citrated blood. The mixing ratio, defined as the ratio of the volumetric flow rates of citrated blood and recalcification buffer, can be adjusted by changing the relative inlet pressures of these two solutions. This feature is useful in whole blood assays in order to account for differences in hematocrit, and thus viscosity. The recalcification process in the herringbone mixer does not activate platelets. The advantage of this continuous mixing approach is demonstrated in microfluidic vascular injury model in which platelets and fibrin accumulate on a collagen-tissue factor surface under flow. Continuous recalcification with the herringbone mixer allowed for flow assay times of up to 30 min, more than three times longer than the time achieved by batch recalcification. This continuous mixer allows for measurements of thrombus formation, remodeling, and fibrinolysis in vitro over time scales that are relevant to these physiological processes. 相似文献
74.
Ethics and Information Technology - This paper examines how digital technologies might be used to improve ethical attitudes towards nonhuman animals, by exploring the case study of nonhuman apes... 相似文献
75.
The present paper summarizes international and national research findings on the general and differential effectiveness of pedagogical work in early childhood education and care settings, evaluations of pilot projects on compensatory preschool education as well programs to support individual learning abilities. Based on these findings, the following conclusions are drawn: First, attending early childhood education and care settings at an early age (after the age of three) has a positive influence on the development of academic competences. Second, the effectiveness of these settings depends on the instructional quality, which could be considerably improved in Germany. Third, pilot projects on programs to support individual learning abilities could show that compensatory effects for disadvantaged groups of children exist, especially when they are interlinked with stimulating conditions in the family and at school. Fourth, effective training programs exist that can be implemented in early childhood education and care. However, a number of challenges need to be met before they can be successfully implemented. 相似文献
76.
Marcus Wagner 《Research Policy》2011,40(9):1217-1225
Innovation in high technology industries poses considerable challenges, frequently forcing firms to consider using acquisitions as a means of sourcing technology. This paper investigates such behaviour in a major high technology sector, namely the semiconductor industry. The paper focuses on differential effects of technology-related versus nontechnological acquisitions on exploratory and exploitative research and innovation. Most importantly, it confirms the important role of technology-related acquisitions for exploratory innovation. 相似文献
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78.
Humberto Arruda Edison Renato Silva Marcus Lessa Domício Proena Jr. Roberto Bartholo 《Journal of the Medical Library Association》2022,110(3):392
VOSviewer (version 1.6.17, July 22, 2021). Centre for Science and Technology Studies, Leiden University, The Netherlands. https://www.vosviewer.com; free, donations accepted.Bibliometrix (version 3.1, Sep 24, 2021). Department of Economics and Statistics, University of Naples Federico II, Italy. ;gro.xirtemoilbib@ofni https://www.bibliometrix.org/; free, donations accepted. 相似文献
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