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81.
IntroductionUnderstanding associations between physical function and neighborhood disadvantage may provide insights into which interventions might best contribute to reducing socioeconomic inequalities in health. This study examines associations between neighborhood-disadvantage, individual-level socioeconomic position (SEP) and physical function from a multilevel perspective.MethodsData were obtained from the HABITAT multilevel longitudinal (2007-13) study of middle-aged adults, using data from the fourth wave (2013). This investigation included 6004 residents (age 46–71 years) of 535 neighborhoods in Brisbane, Australia. Physical function was measured using the PF-10 (0–100), with higher scores indicating better function. The data were analyzed using multilevel linear regression and were extended to test for cross-level interactions by including interaction terms for different combinations of SEP (education, occupation, household income) and neighborhood disadvantage on physical function.ResultsResidents of the most disadvantaged neighborhoods reported significantly lower physical function (men: β − 11.36 95% CI − 13.74, − 8.99; women: β − 11.41 95% CI − 13.60, − 9.22). These associations remained after adjustment for individual-level SEP. Individuals with no post-school education, those permanently unable to work, and members of the lowest household income had significantly poorer physical function. Cross-level interactions suggested that the relationship between household income and physical function is different across levels of neighborhood disadvantage for men; and for education and occupation for women.ConclusionLiving in a disadvantaged neighborhood was negatively associated with physical function after adjustment for individual-level SEP. These results may assist in the development of policy-relevant targeted interventions to delay the rate of physical function decline at a community-level.  相似文献   
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ObjectiveHigh fluctuations in injury-risk during the playing season in soccer have been reported. As seasons are structured in periods with homogenous loads and intensities, we investigated injury-risk over season periods, contrarily to previous studies adopting a month-based approach.DesignCohort study; Level of evidence, 2.MethodsIncidence-rate ratios (IRRs) for match and training injuries were compared across six consecutive seasons of German Bundesliga, divided into six periods each: Pre-season (PS), winter-break (WB), quarter 1–4: (Q1–Q4).ResultsSignificant variations in injury-risk were observed for match and training injuries. IRRs in matches was 1.30 (95% CI: 1.11–1.53) times higher in Q3 and 1.53 (95% CI: 1.31–1.78) higher in Q4 compared to Q1. For training injuries, IRR peaked in Q1 and Q3 followed by a marked decrease in each subsequent quarter. Compared to Q4, IRR was 1.62 (95% CI: 1.40–1.86) times higher during Q3 and 1.78 (95% CI: 1.53–2.07) times higher in Q1. IRR was significantly higher in the competitive season compared to pre-season across match (IRR: 2.00, 95% CI: 1.30–3.00) and training (IRR: 1.27, 95% CI: 1.11–1.43) injuries.ConclusionsThe increased match IRRs later during the season indicate that, in practice, coaches should consider putting even more emphasis on recovery in the last part of the season. Moreover, training injuries seem to indicate a carry-over effect. Further studies need to investigate how training during preparatory phases can be implemented in a way that prevents injuries during the competitive season.  相似文献   
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《Vaccine》2020,38(51):8185-8193
BackgroundWhile administration of the measles-mumps-rubella (MMR-II®) vaccine has been effective at preventing rubella infection in the United States, the durability of humoral immunity to the rubella component of MMR vaccine has not been widely studied among older adolescents and adults.MethodsIn this longitudinal study, we sought to assess the durability of rubella virus (RV)-specific humoral immunity in a healthy population (n = 98) of adolescents and young adults at two timepoints: ~7 and ~17 years after two doses of MMR-II® vaccination. Levels of circulating antibodies specific to RV were measured by ELISA and an immune-colorimetric neutralization assay. RV-specific memory B cell responses were also measured by ELISpot.ResultsRubella-specific IgG antibody titers, neutralizing antibody titers, and memory B cell responses declined with increasing time since vaccination; however, these decreases were relatively moderate. Memory B cell responses exhibited a greater decline in men compared to women.ConclusionsCollectively, rubella-specific humoral immunity declines following vaccination, although subjects’ antibody titers remain well above the currently recognized threshold for protective immunity. Clinical correlates of protection based on neutralizing antibody titer and memory B cell ELISpot response should be defined.  相似文献   
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A multitude of athletic injuries occur when the various tissues that make up the human body experience stresses and strains that exceed their material strength. The precise amount of stress and strain that any given tissue can withstand is determined by the mechanical properties and resultant strength of that particular tissue. These mechanical properties are directly determined by an individual’s physiology and acute regulation of these properties. A number of theoretical frameworks for athletic injury occurrence have been proposed, however, a detailed conceptual framework for injury aetiology that considers the interplay between the physiological and mechanical factors and outlines the causal pathways to tissue damage and injury is needed. This will guide injury research towards a more thorough investigation of causal mechanisms and understanding of risk factors. Further, it is important to take into account the considerable differences in loading patterns which can result in varying injury outcomes such as acute stress-related, strain-related, or overuse injury. Within this article a simplified conceptual model of athletic injury is proposed along with a detailed, evidence-informed, conceptual framework for athletic injury aetiology that focuses on stress-related, strain-related, and overuse injury.  相似文献   
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BackgroundIn the United States, the National School Lunch Program (NSLP) is the healthiest lunch option for students, yet participation is suboptimal and fruit and vegetable waste remains high. Improving school meal convenience, engaging teachers in the school-lunch program, and enhancing the cafeteria environment are promising strategies to improve participation and dietary intake, yet little evidence is available on their impact.Methods/designThe Multi-Pronged Intervention to Increase Secondary Student Participation in School Lunch (MPI) is a 3-year quasi-experimental study in a large urban school district in California. A total of 24 middle and high schools participated in the study: half received the intervention and half served as controls. The intervention consisted of additional school lunch points of sale (vending machines and mobile carts), a school meal outreach program for teachers, and cafeteria redesigns. School meal participation, student-reported fruit and vegetable consumption, and school lunch plate waste were assessed at baseline and in years 1 and 2 of the intervention. Change in meal participation and fruit and vegetable consumption were compared between intervention and control arms to determine the impact of the intervention on school meal participation and dietary intake.DiscussionThis study is positioned to provide evidence on the feasibility and efficacy of a multi-level intervention to increase school meal participation and consumption of fruits and vegetables.  相似文献   
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