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141.
This study presents a worked example of a stepped process to reliably estimate the habitual physical activity and sedentary time of a sample of young children. A total of 299 children (2.9 ± 0.6 years) were recruited. Outcome variables were daily minutes of total physical activity, sedentary time, moderate to vigorous physical activity and proportional values of each variable. In total, 282 (94%) provided 3 h of accelerometer data on ≥1 day and were included in a 6-step process: Step-1: determine minimum wear-time; Step-2: process 7-day-data; Step-3: determine the inclusion of a weekend day; Step-4: examine day-to-day variability; Step-5: calculate single day intraclass correlation (ICC) (2,1); Step-6: calculate number of days required to reach reliability. Following the process the results were, Step-1: 6 h was estimated as minimum wear-time of a standard day. Step-2: 98 (32%) children had ≥6 h wear on 7 days. Step-3: no differences were found between weekdays and weekend days (P ≥ 0.05). Step-4: no differences were found between day-to-day variability (P ≥ 0.05). Step-5: single day ICC’s (2,1) ranged from 0.48 (total physical activity and sedentary time) to 0.53 (proportion of moderate to vigorous physical activity). Step-6: to reach reliability (ICC = 0.7), 3 days were required for all outcomes. In conclusion following a 7 day wear protocol, ≥6 h on any 3 days was found to have acceptable reliability. The stepped-process offers researchers a method to derive sample-specific wear-time criterion.  相似文献   
142.
The development of a comprehensive protocol for quantifying soccer-specific skill could markedly improve both talent identification and development. Surprisingly, most protocols for talent identification in soccer still focus on the more generic athletic attributes of team sports, such as speed, strength, agility and endurance, rather than on a player’s technical skills. We used a multivariate methodology borrowed from evolutionary analyses of adaptation to develop our quantitative assessment of individual soccer-specific skill. We tested the performance of 40 individual academy-level players in eight different soccer-specific tasks across an age range of 13–18 years old. We first quantified the repeatability of each skill performance then explored the effects of age on soccer-specific skill, correlations between each of the pairs of skill tasks independent of age, and finally developed an individual metric of overall skill performance that could be easily used by coaches. All of our measured traits were highly repeatable when assessed over a short period and we found that an individual’s overall skill – as well as their performance in their best task – was strongly positively correlated with age. Most importantly, our study established a simple but comprehensive methodology for assessing skill performance in soccer players, thus allowing coaches to rapidly assess the relative abilities of their players, identify promising youths and work on eliminating skill deficits in players.  相似文献   
143.
Motor performance is an important health resource. Review articles revealed a decline of motor performance of approximately 10?% between 1975 and 2006. In the past most of the data available for such comparisons came from ad hoc studies with non-standardized methods. Within the framework of the ”Motorik-Modul“ (MoMo) study as part of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS), it is possible for the first time to directly compare two cohorts in the ages of 4–17 years in a nationally representative database for Germany. The aim of this article is to report changes in motor performance of children and adolescents in the time period 2003–2006 (cohort baseline n = 4528) compared to 2009–2012 (cohort wave 1, n = 2820). Overall, it is clearly shown that the motor performance of children and adolescents in Germany did not decrease within the observational period of 6 years. The comparison of mean values of the baseline cohort compared to those of wave 1 showed that 28 out of 52 mean values of the two cohorts with a high probability did not differ based on 95?% confidence intervals (CI). In 24 out of the 52 mean values positive changes could be noted based on the individual 95?% CI values. There were more positive changes in primary school aged children than in other age groups. Within these positive changes, most effect sizes were small to medium. The results indicate that recent activities aiming at elevating motor performance levels may have started to make an impact and should be expanded, also in secondary schools. The comparative cohort study presented in this article is currently being checked by the ongoing MoMo wave 2 survey of 2014–2017.  相似文献   
144.
Abstract

Motorsport is an under-researched area of socio-historical study. There is particularly limited academic understanding of female involvement in the social world of motorsports. Therefore, this paper focuses on the role of the media in presenting and establishing motorsport for women. In particular, a documentary analysis of articles published by a UK national newspaper group from 1890, and a case study of an all-female UK-based motor-racing championship are used to account for gendered processes that have influenced attitudes and behaviours towards women motor racers. The motor car emerged through technological progress in an overtly masculine-dominated industrial period. Traditional assumptions and biologically deterministic attitudes towards women were used by men to position motoring and motor-racing as a male preserve. Newspaper reporting throughout the 1930s suggests an era of heightened success for women motor racers as a result of gaining access to a key resource in the form of Brooklands motor-racing circuit. Following the Second World War, there was increasing commercialization and professionalization of male-dominated motorsport, as well as renewed marginalization and trivialization of female participants within the newspapers. These processes continue to influence perceptions of women in contemporary motorsport.  相似文献   
145.
The aims of this study were to describe normative values and seasonal variation of body composition in female cyclists comparing female road and track endurance cyclists, and to validate the use of anthropometry to monitor lean mass changes. Anthropometric profiles (seven site skinfolds) were measured over 16 years from 126 female cyclists. Lean mass index (LMI) was calculated as body weight?×?skinfolds?x. The exponent (x) was calculated as the slope of the natural logarithm of body weight and skinfolds. Percentage changes in LMI were compared to lean mass changes measured using dual-energy X-ray absorptiometry (DXA) in a subset of 25 road cyclists. Compared to sub-elite and elite cyclists, world class cyclists were (mean [95% CI]) 1.18?kg [0.46, 1.90] and 0.60?kg [0.05, 1.15] lighter and had skinfolds that were 7.4?mm [3.8, 11.0] and 4.6?mm [1.8, 7.4] lower, respectively. Body weight (0.41?kg [0.04, 0.77]) and skinfolds (4.0?mm [2.1, 6.0]) were higher in the off-season compared to the early-season. World class female road cyclists had lower body weight (6.04?kg [2.73, 9.35]) and skinfolds (11.5?mm [1.1, 21.9]) than track endurance cyclists. LMI (mean exponent 0.15 [0.13, 0.18]) explained 87% of the variance in DXA lean mass. In conclusion, higher performing female cyclists were lighter and leaner than their less successful peers, road cyclists were lighter and leaner than track endurance cyclists, and weight and skinfolds were lowest early in the season. LMI appears to be a reasonably valid tool for monitoring lean mass changes.  相似文献   
146.
Instructional Science - Engaging in engineering tasks can help students learn science concepts. However, many engineering tasks lead students to focus more on the success of their construction than...  相似文献   
147.

Objective

The authors explored the feasibility and possible benefit of tablet-based educational materials for patients in clinic waiting areas.

Methods

We distributed eight tablets preloaded with diagnosis-relevant information in two clinic waiting areas. Patients were surveyed about satisfaction, usability, and effects on learning. Technical issues were resolved.

Results

Thirty-seven of forty patients completed the survey. On average, the patients were satisfied in all categories.

Conclusions

Placing tablet-based educational materials in clinic waiting areas is relatively easy to implement. Patients using tablets reported satisfaction across three domains: usability, education, and satisfaction.  相似文献   
148.
Borck  C. Ray 《The Urban Review》2020,52(2):376-391

Despite persistent class and race inequalities in educational attainment and achievement in the U.S., hegemonic cultural ideologies and urban education politics and policies continue to proceed from an insistence that education is the great equalizer. These ideologies do not take into account the ways that normative school culture and pedagogical praxes take for granted middle-class, white-supremacist cultural assumptions that privilege student populations whose social locations already probabilize high rates of achievement and attainment. Vast research published in The Urban Review and elsewhere has demonstrated the importance and efficacy of culturally sustaining pedagogy for improving outcomes for economically marginalized students of color (Allen in Urban Rev 47(1):209–231, 2015; Delpit in Harv Educ Rev 56(4):379–386, 1995; Farinde-Wu et al. in Urban Rev 49(2):279–299, 2017; Gay in culturally responsive teaching: theory, research, and practice, Teachers College Press, New York, 2010; Graves in Berkeley Rev Educ 5(1):5–32, 2014; Jemal in Urban Rev 49(4):602–626, 2017; Ladson-Billings in Crossing over to Canaan: the journey of new teachers in classrooms, Jossey-Bass, San Francisco, 2001, The dreamkeepers: successful teachers of African American children, Jossey-Bass Publishers, San Francisco, 2009; Lee in Culture, literacy and learning: taking bloom in the midst of the whirlwind, Teachers College Press, New York, 2006; Marciano in Urban Rev 49(1):169–187, 2016; Nieto in Language, culture, and teaching: critical perspectives, Routledge, New York, 2010; Paris in Educ Res 41(3):93–97, 2012; Paris and Alim in Culturally sustaining pedagogies: teaching and learning for justice in a changing world, Teachers College Press, New York, 2017; Wiggan and Watson in Urban Rev 48(5):766–798, 2016; Yosso in Race Ethn Edu, 8(1):69–91, 2005). This article uses rich ethnographic data from a transfer school in Brooklyn, New York that serves financially insecure youth of color who are “over-age and under-credited.” These data and my analysis showcase the expertise and indigenous knowledges of teachers who practice cultural relevance and critical racial awareness in order to engage, retain, graduate and prepare students who are historically and presently marked for failure by an education system that has always been more adept at reproducing social inequality than disrupting it (Borck in Qual Inq 20(10):1–8, 2016).

  相似文献   
149.
Purpose: This paper reports the results of survey research conducted with tribal producers between 2011 and 2012 on 19 of the largest American Indian reservations in Idaho, Nevada, North Dakota, Oregon, South Dakota, and Washington. The purpose of the research was to identify potential barriers to sustainable agriculture on reservation lands. This article reports the results of this research in an effort to promote Extension professionals' understanding of these barriers, which may help to improve outreach programs on American Indian reservations. Understanding the obstacles to sustaining agriculture that American Indian tribes face may inform international agricultural outreach efforts to increase food security targeting indigenous and tribal peoples worldwide.

Design/Methodology/Approach: American Indian agricultural producers comprised the study group. Study objectives included: (1) identify agricultural and natural resource issues of greatest concern to a self-selected sample of tribal agricultural producers on reservation lands; (2) evaluate access to Extension and other US Department of Agriculture outreach and assistance programs; and (3) evaluate the quality of these programs in terms of their relativity to tribal needs.

Findings: Study results indicate that tribal agricultural producers surveyed ranked 29 of 39 agricultural and natural resource issues as a concern. Similarly, they rated access to and quality of outreach programs as fair. Further, tribal producers operating on reservation trust land rated issues more severely than did tribal producers operating on fee simple lands.

Practical Implications: Results of this research will help Extension and other outreach professionals to understand the barriers indigenous and tribal peoples face in sustaining agricultural operations, particularly tribal groups living on federally reserved trust lands, such as American Indians. An increased understanding can inform agricultural policy-makers and outreach professionals in improving programs designed to increase agricultural sustainability, improve food security, enhance economic well-being and improve quality of life of indigenous and tribal peoples worldwide.

Originality/Value: This research provides important information to agricultural policy-makers and Extension professionals striving to sustain agricultural productivity and enhance food security with indigenous and tribal peoples.  相似文献   

150.
OBJECTIVE: To assess: (1) ethnic differences in the health-risk behaviors, mental health problems, and adverse parenting beliefs during pregnancy of low-income Mexican American and European American women; and, (2) the extent to which these risks varied with levels of acculturation among low-income Mexican American women. METHOD: Participants were 594 primiparous, low-income, urban women. A cross-sectional design was used to compare the 331 Mexican American women to the 263 European American. Language was used to assess the level of acculturation of the Mexican American women. Interviews were used to evaluate health-risk behaviors, mental health problems, and adverse parenting beliefs. RESULTS: In comparison to European American women, Mexican American women were at lower risk for cigarette smoking during pregnancy and higher risk for adverse parenting beliefs. Among Mexican American women, Spanish speakers were at lower risk for cigarette smoking and mental health problems during pregnancy, and higher risk for adverse parenting beliefs than bilingual and English speakers. CONCLUSIONS: The findings indicate that ethnic differences in cigarette smoking and parenting beliefs during pregnancy were concentrated on the less acculturated, low-income, and primarily unmarried Spanish speaking Mexican American women. Moreover, acculturation is differentially related to cigarette smoking and parenting beliefs. Therefore, acculturation needs to be considered in the development of preventive interventions in order to appropriately target the specific needs of different sub-populations of Mexican Americans.  相似文献   
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