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ObjectivesTo assess the relationship between proximity to specific sports facilities and participation in the corresponding sports activities for adolescents in Germany.MethodsA sample of 1,768 adolescents aged 11–17 years old and living in 161 German communities was examined. Distances to the nearest sports facilities were calculated as an indicator of proximity to sports facilities using Geographic Information Systems (GIS). Participation in specific leisure-time sports activities in sports clubs was assessed using a self-report questionnaire and individual-level socio-demographic variables were derived from a parent questionnaire. Community-level socio-demographics as covariates were selected from the INKAR database, in particular from indicators and maps on land development. Logistic regression analyses were conducted to examine associations between proximity to the nearest sports facilities and participation in the corresponding sports activities.ResultsThe logisitic regression analyses showed that girls residing longer distances from the nearest gym were less likely to engage in indoor sports activities; a significant interaction between distances to gyms and level of urbanization was identified. Decomposition of the interaction term showed that for adolescent girls living in rural areas participation in indoor sports activities was positively associated with gym proximity. Proximity to tennis courts and indoor pools was not associated with participation in tennis or water sports, respectively.ConclusionsImproved proximity to gyms is likely to be more important for female adolescents living in rural areas.

BackgroundThe measurement of activity energy expenditure (AEE) via accelerometry is the most commonly used objective method for assessing human daily physical activity and has gained increasing importance in the medical, sports and psychological science research in recent years.ObjectiveThe purpose of this study was to determine which of the following procedures is more accurate to determine the energy cost during the most common everyday life activities; a single regression or an activity based approach. For this we used a device that utilizes single regression models (GT3X, ActiGraph Manufacturing Technology Inc., FL., USA) and a device using activity-dependent calculation models (move II, movisens GmbH, Karlsruhe, Germany).Material and MethodsNineteen adults (11 male, 8 female; 30.4±9.0 years) wore the activity monitors attached to the waist and a portable indirect calorimeter (IC) as reference measure for AEE while performing several typical daily activities. The accuracy of the two devices for estimating AEE was assessed as the mean differences between their output and the reference and evaluated using Bland-Altman analysis.ResultsThe GT3X overestimated the AEE of walking (GT3X minus reference, 1.26 kcal/min), walking fast (1.72 kcal/min), walking up−/downhill (1.45 kcal/min) and walking upstairs (1.92 kcal/min) and underestimated the AEE of jogging (−1.30 kcal/min) and walking upstairs (−2.46 kcal/min). The errors for move II were smaller than those for GT3X for all activities. The move II overestimated AEE of walking (move II minus reference, 0.21 kcal/min), walking up−/downhill (0.06 kcal/min) and stair walking (upstairs: 0.13 kcal/min; downstairs: 0.29 kcal/min) and underestimated AEE of walking fast (−0.11 kcal/min) and jogging (−0.93 kcal/min).ConclusionsOur data suggest that the activity monitor using activity-dependent calculation models is more appropriate for predicting AEE in daily life than the activity monitor using a single regression model.

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Previously, we have found that acetaldehyde, a volatile component of cigarette smoke, stimulates the protein kinase C (PKC) pathway and inhibits ciliary motility. A "smokeless" cigarette (Eclipse) now exists in which most of the tobacco is not burned, reducing the pyrolyzed components in the extract. We hypothesized that acetaldehyde is a component of cigarette smoke that activates PKC in the airway epithelial cell, and therefore the Eclipse cigarette would not activate epithelial cell PKC. In this study, bovine bronchial epithelial cells (BBEC) were incubated with cigarette smoke extract (CSE) or Eclipse smoke extract (ESE). We found that PKC activity was significantly higher in cells exposed to 5% CSE than cells exposed to 5% ESE or media. When acetaldehyde levels of both extracts were measured by gas chromatography, CSE was found to have 15-20 times greater concentration (microM) of acetaldehyde than ESE. When BBEC were treated with 5% CSE, ciliary beating was further decreased from baseline levels. This decrease in ciliary beating was not observed in cells treated with ESE, suggesting that acetaldehyde contained in CSE slows cilia. These results suggest that volatile components such as acetaldehyde in cigarette smoke may inhibit ciliary motility via a PKC-dependent mechanism.

BackgroundThe bias caused by drop-out is an important factor in large population-based epidemiological studies. Many studies account for it by weighting their longitudinal data, but to date there is no detailed final approach for how to conduct these weights.MethodsIn this study we describe the observed longitudinal bias and a three-step longitudinal weighting approach used for the longitudinal data in the MoMo baseline (N = 4528, 4–17 years) and wave 1 study with 2807 (62%) participants between 2003 and 2012.ResultsThe most meaningful drop-out predictors were socioeconomic status of the household, socioeconomic characteristics of the mother and daily TV usage. Weighting reduced the bias between the longitudinal participants and the baseline sample, and also increased variance by 5% to 35% with a final weighting efficiency of 41.67%.ConclusionsWe conclude that a weighting procedure is important to reduce longitudinal bias in health-oriented epidemiological studies and suggest identifying the most influencing variables in the first step, then use logistic regression modeling to calculate the inverse of the probability of participation in the second step, and finally trim and standardize the weights in the third step.

Abstract. Previously, we have found that acetaldehyde, a volatile component of cigarette smoke, stimulates the protein kinase C (PKC) pathway and inhibits ciliary motility. A “smokeless” cigarette (Eclipse) now exists in which most of the tobacco is not burned, reducing the pyrolyzed components in the extract. We hypothesized that acetaldehyde is a component of cigarette smoke that activates PKC in the airway epithelial cell, and therefore the Eclipse cigarette would not activate epithelial cell PKC. In this study, bovine bronchial epithelial cells (BBEC) were incubated with cigarette smoke extract (CSE) or Eclipse smoke extract (ESE). We found that PKC activity was significantly higher in cells exposed to 5% CSE than cells exposed to 5% ESE or media. When acetaldehyde levels of both extracts were measured by gas chromatography, CSE was found to have 15–20 times greater concentration (μM) of acetaldehyde than ESE. When BBEC were treated with 5% CSE, ciliary beating was further decreased from baseline levels. This decrease in ciliary beating was not observed in cells treated with ESE, suggesting that acetaldehyde contained in CSE slows cilia. These results suggest that volatile components such as acetaldehyde in cigarette smoke may inhibit ciliary motility via a PKC‐dependent mechanism.

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