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121.
Stephen D. Herrmann Kristin J. Heumann Cheryl A. Der Ananian Barbara E. Ainsworth 《Measurement in physical education and exercise science》2013,17(3):221-235
There is limited published validity and reliability evidence to support using the Global Physical Activity Questionnaire. Two studies were conducted to evaluate validity and reliability evidence for the Global Physical Activity Questionnaire. In Study 1: 69 adults completed the Global Physical Activity Questionnaire (three months apart; n?=?54), International Physical Activity Questionnaire, fitness and anthropometric measures. All participants wore a pedometer and 53 participants wore an accelerometer for seven days at baseline. In Study 2, 16 adults completed the Global Physical Activity Questionnaire 10 days apart. Global Physical Activity Questionnaire moderate and vigorous minutes were correlated with the accelerometer moderate (r?=?0.28) and vigorous (r?=?0.48) physical activity. The Global Physical Activity Questionnaire and International Physical Activity Questionnaire were related for sedentary behaviors (r?=?0.51), moderate-to-vigorous (r?=?0.48) and vigorous (r?=?0.63) PA. Global Physical Activity Questionnaire moderate-to-vigorous physical activity was associated with percent fat (r =??0.32), estimated VO2 max (r?=?0.26), and step count (r?=?0.39). The Global Physical Activity Questionnaire demonstrated graded differences across categories for step count, body mass index, waist circumference, percent fat, fitness, and accelerometer measured activity. Short-term test–retest reliability (10 days) ranged from 0.83 to 0.96 while long-term reliability (three months) was 0.53 to 0.83. These data provide low-to-moderate validity and generally acceptable reliability evidence for the Global Physical Activity Questionnaire. 相似文献
122.
Part of the promise of electronic government (e-government) is its ability to transform the delivery of information services and products from government to users. E-government allows federal agencies to supplement and even supplant private sector roles intermediating between government agencies and users, creating unintended consequences in terms of policy, theory, and practice. The problem is called “channel conflict” in the marketing literature, and the typical response is called distribution channel management (DCM). After reviewing the literatures of e-government, information policy, and DCM, the paper explores differing DCM philosophies of two federal agencies: the Internal Revenue Service and the U.S. Census Bureau. An examination of these two DCM programs provides insights on how federal agencies may be able to manage their various channels for e-government offerings despite tensions in the current legal and policy context. The paper concludes by using DCM literature to help frame options for dealing with these tensions. 相似文献
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Logan SW Scrabis-Fletcher K Modlesky C Getchell N 《Research quarterly for exercise and sport》2011,82(3):442-448
The purpose of this study was to examine the relationship between motor proficiency and body mass index (B/MI) in preschool children. Thirty-eight children ages 4-6 years had their BMI calculated and were assessed using the Movement Assessment Battery for Children-2 (MABC-2; Henderson, Sugden, & Barnett, 2007). These data were analyzed in two ways. The correlation between BMI and MABC-2 percentile ranks was calculated. Next, the groups were subdivided based on BMI status (high, M = 85.5; medium, M = 49.8; low, M = 10.8), and compared using t tests to determine if differences existed in MABC-2 percentile ranks. No significant relationship existed between MABC-2 and BMI percentile ranks (r = -.237). However significant differences in MABC-2 percentile ranks existed between high and low (p = .042), and high and medium (p = .043) groups. These results suggest that preschool children classified as overweight or obese may have lower motor proficiency than their normal weight and under weight peers. This study indicates there is a direct relationship between motor proficiency and BMI in the preschool population. 相似文献
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In a recent paper Professor John Zeleny published curves obtained for ion mobilities at different ion ages in relatively pure N2 using his classical air blast method. Two features are of especial interest; one the apparent gradual displacement of the negative ion peak to lower mobilities as the ion age increases and the other a marked asymmetry of the electron peak on the low mobility side. This Zeleny interprets as an unresolved negative ion mobility of value about 100 cm./sec. per volt/cm. Such a mobility can only be explained by a carrier that is ion part of its life and electron part of its life, the electronic and ionic phases alternating frequently. The writers indicate that the latter interpretation cannot be correct on the basis of the energies and probabilities involved in electron attachment. Analysis shows that the whole series of the observed phenomena in N2 by this method are successfully accounted for on the proper application of the simplified theory of electron attachment to the air blast method. Since the attachment phenomena have to date not been applied to this type of mobility study it was felt of importance to present this analysis in order to guide future investigations by this method. 相似文献
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This study examined the incidence, severity, and timing of gastrointestinal (GI) symptoms in finishers and non-finishers of the 161-km Western States Endurance Run. A total of 272 runners (71.0% of starters) completed a post-race questionnaire that assessed the incidence and severity (none = 0, mild = 1, moderate = 2, severe = 3, very severe = 4) of 12 upper (reflux/heartburn, belching, stomach bloating, stomach cramps/pain, nausea, vomiting) and lower (intestinal cramps/pain, flatulence, side ache/stitch, urge to defecate, loose stool/diarrhoea, intestinal bleeding/bloody faeces) GI symptoms experienced during each of four race segments. GI symptoms were experienced by most runners (96.0%). Flatulence (65.9% frequency, mean value 1.0, s = 0.6 severity), belching (61.3% frequency, mean value 1.0, s = 0.6 severity), and nausea (60.3% frequency, mean value 1.0, s = 0.7 severity) were the most common symptoms. Among race finishers, 43.9% reported that GI symptoms affected their race performance, with nausea being the most common symptom (86.0%). Among race non-finishers, 35.6% reported that GI symptoms were a reason for dropping out of the race, with nausea being the most common symptom (90.5%). For both finishers and non-finishers, nausea was greatest during the most challenging and hottest part of the race. GI symptoms are very common during ultramarathon running, and in particular, nausea is the most common complaint for finishers and non-finishers. 相似文献