The objective of this study was to determine whether obesity prevalence and weight‐related behaviors (e.g., diet, physical activity) differ among students enrolled in 2‐year community/technical ...colleges and those attending 4‐year colleges/universities. This information could inform the development of intervention strategies. Through an existing surveillance system of Minnesota postsecondary education institutions, survey data were collected from 16,539 students from 27 campuses (14 two‐year college campuses, 13 four‐year college/university campuses; 2007–2008), including self‐reported physical activity, media use, dietary patterns, weight control behaviors, height, and weight. Unadjusted analyses indicated that students enrolled in 2‐year colleges, particularly females, had a higher prevalence of overweight/obesity, lower levels of physical activity, more television viewing, higher intakes of soda, fast food, and diet pills compared to students attending 4‐year colleges (P < 0.05). Females attending 4‐year colleges were more likely to engage in certain unhealthy weight control behaviors (taking diet pills, binge eating, self‐induced vomiting) compared to females attending 2‐year institutions. Among male students there were fewer differences between 2‐year and 4‐year colleges. Controlling for sociodemographic factors (e.g., race/ethnicity, age), most disparities in prevalence estimates remained, though many were attenuated. Overall, few young adults engage in weight‐related behaviors consistent with national recommendations. Two‐year college students may represent a particularly at‐risk group. Disparities between 2‐ and 4‐year college students exist beyond the sociodemographic differences in these populations. Effective weight‐related interventions are needed for young adults, particularly females attending 2‐year colleges and all males attending postsecondary institutions.
The validation of a home food inventory Fulkerson, Jayne A; Nelson, Melissa C; Lytle, Leslie ...
The international journal of behavioral nutrition and physical activity,
11/2008, Letnik:
5, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Home food inventories provide an efficient method for assessing home food availability; however, few are validated. The present study's aim was to develop and validate a home food inventory that is ...easily completed by research participants in their homes and includes a comprehensive range of both healthful and less healthful foods that are associated with obesity.
A home food inventory (HFI) was developed and tested with two samples. Sample 1 included 51 adult participants and six trained research staff who independently completed the HFI in participants' homes. Sample 2 included 342 families in which parents completed the HFI and the Diet History Questionnaire (DHQ) and students completed three 24-hour dietary recall interviews. HFI items assessed 13 major food categories as well as two categories assessing ready-access to foods in the kitchen and the refrigerator. An obesogenic household food availability score was also created. To assess criterion validity, participants' and research staffs' assessment of home food availability were compared (staff = gold standard). Criterion validity was evaluated with kappa, sensitivity, and specificity. Construct validity was assessed with correlations of five HFI major food category scores with servings of the same foods and associated nutrients from the DHQ and dietary recalls.
Kappa statistics for all 13 major food categories and the two ready-access categories ranged from 0.61 to 0.83, indicating substantial agreement. Sensitivity ranged from 0.69 to 0.89, and specificity ranged from 0.86 to 0.95. Spearman correlations between staff and participant major food category scores ranged from 0.71 to 0.97. Correlations between the HFI scores and food group servings and nutrients on the DHQ (parents) were all significant (p < .05) while about half of associations between the HFI and dietary recall interviews (adolescents) were significant (p < .05). The obesogenic home food availability score was significantly associated (p < .05) with energy intake of both parents and adolescents.
This new home food inventory is valid, participant-friendly, and may be useful for community-based behavioral nutrition and obesity prevention research. The inventory builds on previous measures by including a wide range of healthful and less healthful foods rather than foods targeted for a specific intervention.
The optimised superconducting stellarator W7-X generates its rotational transform by means of external coils, therefore no toroidal current is necessary for plasma confinement. Electron cyclotron ...current drive experiments were conducted for strikeline control and safe divertor operation. During current drive experiments periodic and repetitive crashes of the central electron temperature, similar to sawtooth crashes in tokamaks, were detected. Measurements from soft x-ray tomography and electron cyclotron emission show that the crashes are preceded by weak oscillating precursors and a displacement of the plasma core, consistent with a (m, n) = (1, 1) mode. The displacement occurs within 100μs, followed by expulsion and redistribution of the core into the external part of the plasma. Two types of crashes, with different frequencies and amplitudes are detected in the experimental program. For these non-stationary parameters a strong dependence on the toroidal current is found. A 1-D heuristic model for current diffusion is proposed as a first step to explain the characteristic crash time. Initial results show that the modelled current diffusion timescale is consistent with the initial crash frequency and that the toroidal current rise shifts the position where the instability is triggered, resulting in larger crash amplitudes.
For the first time, the optimized stellarator Wendelstein 7-X has operated with an island divertor. An operation regime in hydrogen was found in which the total plasma radiation approached the ...absorbed heating power without noticeable loss of stored energy. The divertor thermography recorded simultaneously a strong reduction of the heat load on all divertor targets, indicating almost complete power detachment. This operation regime was stably sustained over several energy confinement times until the preprogrammed end of the discharge. The plasma radiation is mainly due to oxygen and is located at the plasma edge. This plasma scenario is reproducible and robust at various heating powers, plasma densities, and gas fueling locations. These experimental results show that the island divertor concept actually works and displays good power dissipation potential, producing a promising exhaust concept for the stellarator reactor line.
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