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71.
We investigated the interplay between characteristics of early childhood circumstances and current socioeconomic conditions and health, focusing specifically on diabetes in mid and late life in Mexico. The analysis used data from the 2001 Mexican Health and Aging Study (MHAS), a large nationally representative study of Mexicans born before 1950. We analyzed the extent to which childhood conditions, such as exposure to infectious diseases, a poor socioeconomic environment, and parental education, affect the risk of diabetes in later life. Our results indicate that individuals age 50 and older who experienced serious health problems before age 10 have a higher risk of having late-life diabetes. There is a significant inverse relationship between maternal education and diabetes in late life of adult offspring. Individuals with better educated mothers have a lower risk of being diabetic after age 50. This relationship remains after controlling for other childhood and adult risk factors. 相似文献
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Dominic Dellweg Dieter Hochrainer Matthias Klauke Jens Kerl Glenn Eiger Dieter Kohler 《Journal of biomechanics》2010,43(4):652-657
There is no published data about mask features that impact skin contact pressure during mask ventilation.To investigate the physical factors of skin contact pressure formation.We measured masks with original and reduced air cushion size and recorded contact pressure. We determined cushion contact and mask areas by planimetric measurements.Contact pressures necessary to prevent air leakage during inspiration exceed inspiratory pressure by 1.01±0.41 hPa independent of cushion size.Contact area, ventilator pressure and mask area during inspiration and expiration impact contact pressure. Mask contact pressures are higher during expiration. The contact pressure increases with increase in inspiratory pressures independent of the ventilator cycle. During expiration, the contact pressure will increase in proportion to the expiratory pressure reduction of the ventilator. The mask with reduced air cushion size developed higher contact pressures.Contact pressure can be reduced by selecting masks with a small mask area in combination with a large mask cushion. 相似文献
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In this paper, we describe a project-based mathematical lab implemented in our Applied Mathematics in Biology course. The Leaky Bucket Lab allows students to parameterize and test Torricelli's law and develop and compare their own alternative models to describe the dynamics of water draining from perforated containers. In the context of this lab students build facility in a variety of applied biomathematical tools and gain confidence in applying these tools in data-driven environments. We survey analytic approaches developed by students to illustrate the creativity this encourages as well as prepare other instructors to scaffold the student learning experience. Pedagogical results based on classroom videography support the notion that the Biology-Applied Math Instructional Model, the teaching framework encompassing the lab, is effective in encouraging and maintaining high-level cognition among students. Research-based pedagogical approaches that support the lab are discussed. 相似文献
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Knechtle B Knechtle P Kohler G 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2008,66(1):73-79
BACKGROUND: In swimmers, the effects of the anthropometric factors, upper extremity length, hand length and body height, on performance over 100 m have been shown, but no data exist about the influence of anthropometric factors on performance in ultra-endurance swimmers. SUBJECTS AND METHODS: Twelve male Caucasian ultra-swimmers participated in our study at the 9th edition in 2007 of the 12-hours-swim in Zurich, Switzerland. We determined body mass, length of arms and legs, body height, circumferences of extremities, skeletal muscle mass and fat mass in order to correlate with the covered distance and to find an effect on race performance. RESULTS: The 12 swimmers achieved an average distance of 29.4 +/- 5.1 km, varying from 22.8 km to 39.1 km during these 12 hours. There was no correlation between body mass, length of arms and legs, body height, circumferences of extremities, skeletal muscle mass and fat mass to race performance. CONCLUSION: In these 12 male ultra-endurance swimmers no effect of the anthropometric parameters body mass, body height, BMI, circumferences of extremities, length of arms and legs, skeletal muscle mass and fat mass, on performance in a 12-hours-swim has been found. 相似文献
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Incorporation of a proline analog into collagen polypeptides was studied by incubating matrix-free tendon cells from 17-day-old chick embryos with cis-4-hydroxy-l-proline. Velocity sedimentation of intracellular polypeptides provided further evidence that incorporation of the analog into protein prevented the pro-α- and pro-γ-chains of procollagen from folding into a stable triple-helical conformation. The size of the newly synthesized intracellular and extracellular protein was examined under conditions which prevented proteolysis during processing of the samples. In contrast to previous observations, the results demonstrated that there was little if any intracellular degradation of nonhelical pro-α-and pro-γ-chains containing the proline analog, and a fraction of the nonhelical pro-γ-chains was secreted into the medium without extensive degradation. In further studies, the cells were incubated with 14C lysine, and the synthesis of glycosylated hydroxylysyl residues was measured in control cells and in cells incubated with cis-4-hydroxy-l-proline. The results demonstrated that the content of glycosylated hydroxylysyl residues in nonhelical pro-γ-chains containing cis-4-hydroxy-l-proline was increased twofold as compared to the triple-helical procollagen in control cells. The results suggested that under control conditions folding into the triplehelical conformation limits the extent of glycosylation of collagen. If folding is prevented or delayed, procollagen polypeptides are more extensively glycosylated. 相似文献