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1.
Background:This study examined the volume and patterns of physical activity(PA) and sedentary time(ST) across different segments of the week among boys and girls.Methods:A total of 188 children aged 7-12 years wore a wrist-mounted ActiGraph GT3 X+accelerometer for 7 days.Time spent in PA and ST was calculated using ActiLife software.The mean number of minutes of light PA,moderate PA,vigorous PA,moderate-to-vigorous PA(MVPA),and ST were calculated per weekday(before school,during school,and after school) and per weekend day(morning and afternoon-evening).Results:After school represented the greatest accumulation of ST compared with before school and during school segments.Boys engaged in225.4 min/day of ST(95% confidence interval(CI):216-235),and girls engaged in 222.2 min/day of ST(95%CI:213-231).During school,boys engaged in significantly more MVPA than girls(46.1 min/day(95%CI:44-48) vs.40.7 min/day(95%CI:39-43)).Across the whole weekday,boys participated in significantly more MVPA than girls(103.9 min/day(95%CI:99-109) vs.95.7 min/day(95%CI:90-101)).The weekend afternoon—evening segment represented the larger accumulation of ST,where boys were significantly more sedentary than girls(367.5 min/day(95%CI:353-382) vs.339.8 min/day(95%CI:325-355),respectively).Conclusion:Our findings suggest that children are highly sedentary and spend little of their time in school in MVPA,especially girls.Routine breaks in school elicit increases in light PA and MVPA.Future work should consider the use of more active breaks within school time to encourage PA and reduce ST.  相似文献   

2.
We studied differences in physical activity (PA), sedentary behaviour (SB), and the types of PA and SB between Finnish girls and boys and children from different socioeconomic backgrounds (SES). We assessed PA, SB, parental education, and household income using detailed questionnaires in a representative population sample of 486 children (238 girls, 248 boys) aged 6–8 years. Girls spent on average 1.7 h/day and boys 2.0 h/day in total PA (p?=?0.002). Altogether 66% of girls and 54% of boys had less than 2 h of total PA per day (p?=?0.012). Girls had lower levels of unsupervised PA (45 vs. 54 min/day, p?=?0.001), supervised PA (1.5 vs. 1.9 h/week, p?=?0.009), and PA during school recess (1.8 vs. 1.9 h/week, p?=?0.032) than boys. Girls had higher levels of total SB (3.8 vs. 3.4 h/day, p?=?0.015) but lower levels of screen-based SB (1.5 vs. 1.9 h/day, p?<?0.001) than boys. Lower parental education and household income were associated with lower levels of supervised PA in girls (p?=?0.011 and p?=?0.008, respectively) and in boys (p?=?0.006 and p?=?0.003, respectively). Lower parental education and household income were also related to higher levels of screen-based SB in boys (p?=?0.005 and p?<?0.001, respectively) but not in girls. Girls have lower levels of total, unsupervised, and supervised PA, PA during recess, and screen-based SB but higher levels of total SB than boys. Lower parental education and household income are associated with lower levels of supervised PA in both genders and higher levels of screen-based SB in boys.  相似文献   

3.
Third and fourth grade boys (n = 422) and girls (n = 390) in four Texas elementary schools reported their participation in moderate to vigorous physical activities (MVPAs) over a 3-day period. Students were surveyed during class on successive days. On a subsample (n = 44), the agreement between reported and observed physical activities during physical education or recess was 86.3%. Running, walking fast, games and sports, and bicycling accounted for 70% of Total MVPAs. Of Total MVPAs reported, 47.0% for boys and 44.6% for girls were 10 min or longer in duration (LMVPA). The average number of LMVPAs per day was 1.7 for both boys and girls. Students reported significantly more occurrences of LMVPAs out of school than during school. Significant interaction between grade and gender indicated that third grade boys reported more Total MVPAs and LMVPAs than third grade girls, but fourth grade boys reported fewer Total MVPAs and LMVPAs than fourth grade girls reported fewer Total MVPAs and LMVPAs than fourth grade girls. During the 3-day reporting period, 12.3% of boys and 13.3% of girls reported no LMVPAs, and 35.6% of boys and girls reported fewer than one LMVPAs per day. While the majority of children reported obtaining at least some activity daily, a substantial proportion of children in this sample reported fewer than one LMVPA daily, indicating that many children may not be obtaining adequate amounts of physical activity.  相似文献   

4.
BackgroundEvidence on correlates relies on subjective metrics and fails to include correlates across all levels of the ecologic model. We determined which correlates best predict sensor-based physical activity (PA), sedentary time (ST), and self-reported cell phone screen time (CST) in a large sample of youth, while considering a multiplicity of correlates.MethodsUsing sensor-based accelerometry, we assessed the PA and ST of 2179 youths. A χ2 automatic interaction detection algorithm was used to hierarchize the correlates associated with too much ST (> 50th percentile), insufficient moderate-to-vigorous PA (MVPA) (<60 min/day), and prolonged CST (≥2 h/day).ResultsAmong youth 10–14 years old, the correlates for being inactive consisted of being a girl, not having sport facilities in the neighborhood, and not perceiving the neighborhood as a safe place, whereas in the youth 15–18 years old, the correlate for being inactive was not performing sports (9.7% chance of being active). The correlates for predicting high ST in the younger group was not performing sports (55.8% chance for high ST), and in the older group, the correlates were not owning a pet, perceiving the neighborhood as safe, and having inactive parents (63.7% chance for high ST). In the younger group, the greatest chances of having high CST were among those who were in the last elementary school years, who were girls, and who did not have friends in the neighborhood (73.1% chance for high CST), whereas in the older group, the greatest chance for having high CST was among those who were girls and had a TV in the bedroom (74.3% chance for high CST).ConclusionTo counteract ST and boost MVPA among youths, a specific focus on girls, the promotion of sport participation and facilities, neighborhood safety, and involvement of family must be prioritized.  相似文献   

5.
Abstract

Third and fourth grade boys (n = 422) and girls (n = 390) in four Texas elementary schools reported their participation in moderate to vigorous physical activities (MVPAs) over a 3-day period. Students were surveyed during class on successive days. On a subsample (n = 44), the agreement between reported and observed physical activities during physical education or recess was 86.3%. Running, walking fast, games and sports, and bicycling accounted for 70% of Total MVPAs. Of Total MVPAs reported, 47.0% for boys and 44.6% for girls were 10 min or longer in duration (LMVPA). The average number of LMVPAs per day was 1.7 for both boys and girls. Students reported significantly more occurrences of LMVPAs out of school than during school. Significant interaction between grade and gender indicated that third grade boys reported more Total MVPAs and LMVPAs than third grade girls, but fourth grade boys reported fewer Total MVPAs and LMVPAs than fourth grade girls. During the 3-day reporting period, 12.3% of boys and 13.3% of girls reported no LMVPAs, and 35.6% of boys and girls reported fewer than one LMVPAs per day. While the majority of children reported obtaining at least some activity daily, a substantial proportion of children in this sample reported fewer than one LMVPA daily, indicating that many children may not be obtaining adequate amounts of physical activity.  相似文献   

6.
Abstract

This study examined whether body perception (BP) and body satisfaction (BS) among adolescents correspond with healthy body size criteria as recommended by various world health authorities, and assessed the relationships between BP and BS and physical activity (PA) among adolescents. Participants included 6274 Israeli boys and girls from grades 7–12 who took part in the first Israeli Health and Nutrition Youth survey. Data regarding their BP and BS, body mass index (BMI) and PA were gathered. Among the overweight and obese participants, 66.4% and 40.6% of the boys, respectively, and 46.7% and 26.1% of the girls, respectively, perceived their body shape and size as satisfactory (OK). Another important finding was that overweight and obese girls were three times more active than underweight girls, and the highest per cent of active boys appeared among the overweight boys or those who perceived themselves as fat. Regression analyses revealed that BMI, gender and age accounted for 29.8% of the variance in participants' BP; BMI, gender and age accounted for 22.1% of BS variance, and PA was not related to either BP or BS. In conclusion, adolescents do not perceive their body according to healthy body size criteria recommended by various world health authorities. In addition, PA as a variable does not explain body image. Therefore, increasing body awareness seems to be a fundamental step in programs that aim to reduce obesity.  相似文献   

7.
Abstract

This study evaluated the influence of biological and environmental variables on the differences between the throwing performance of 5-year-old girls and boys. A total of 100 children (48 girls, 52 boys) were tested on throwing for distance and rated on two components of throwing form—trunk rotation, and foot action. Children were evaluated on eight biological characteristics—height, weight, body mass index, ponderal index, sum of four skinfolds, body diameters, arm and leg girths, and somatotypes—and four environmental characteristics—older brother, older sister, presence of adult male, and playing with older children. Results indicated that boys threw farther than girls and exhibited more mature form. Boys had greater joint diameters than girls, a smaller sum of four skinfolds, and more estimated arm muscle. Boys were more likely to play regularly with older children. Girls' throwing performance was only 57% that of boys, but when throwing was adjusted for a linear composite of biological variables, girls' throwing performance increased to 69% of boys'. Thus, while the differences in most motor performance tasks between boys and girls prior to puberty have been attributed to environmental factors, some of the differences in throwing performance appears to reflect biological characteristics, even as early as 5 years of age.  相似文献   

8.
Abstract

As an increase in pain symptoms among children has been shown in the last decades, the aim of this study was to describe perceptions of recurrent pain, measured physical fitness and levels of reported physical activity (PA) in children, and to investigate if any associations between PA, fitness and recurrent pain could be identified. A school-based study comprised 206 Swedish children 8–12 years old, 114 boys, 92 girls. A questionnaire with questions about perceived pain, self-reported PA and lifestyle factors was used. Health-related fitness was assessed by 11 physical tests. A physical index was calculated from these tests as a z score. High physical index indicated high fitness and low physical index indicated low fitness. ANOVA test, chi-square test and logistic regression analysis were used to compare active and inactive children. The prevalence of one pain location (head, abdomen or back) was 26%, two 11% and three 4% (n=206). Female gender, living in single-parent families, low PA and low subjective health were associated with reported recurrent pain. Children reporting high levels of PA had high physical index and reported low prevalence of pain symptoms. The physical index and level of self-reported PA decreased gradually the more pain locations. Physically active children had higher fitness levels and reported less pain symptoms than inactive peers. Coping with pain is an integral part of PA, and active children learn to cope with unpleasant body sensations which together with high fitness may reduce the perception of pain.  相似文献   

9.
PurposeThe aims of this study were to (a) describe gender inequalities in physical activity (PA) among adolescents from Global South countries, and (b) investigate the relationship between gender inequalities in PA and contextual factors, such as geographic region, human development index, gender inequality index, and unemployment rates.MethodsWe analyzed cross-sectional data from the Global School-Based Student Health Survey conducted in Global South countries between 2010 and 2020 among 13- to 17-year-old adolescents. Country-context variables were retrieved from secondary data sources (World Health Organization, World Bank, and Human Development Reports). PA was assessed by a self-administered questionnaire querying the number of days in the past week in which participants were physically active for a total of at least 60 min. PA absolute gender inequalities were evaluated by the differences in the prevalence between boys and girls, 95% confidence intervals (95%CIs) were estimated using the bootstrap method. Relative inequalities were obtained through Poisson regression. Meta-analyses with random effects were used to calculate pooled estimates of absolute and relative inequalities.ResultsBased on 64 Global South countries/surveys, the prevalence of PA was 6.7 percentage points (p.p.) higher in boys than in girls, ranging from 0.5 p.p. in Afghanistan to 15.6 p.p. in Laos (I2= 85.1%). The pooled ratio for all countries showed that boys presented a PA prevalence 1.58 times higher than girls (95%CI: 1.47–1.70) on average. The highest absolute and relative inequalities were observed in high income countries. Countries with higher Human Development Index rankings and lower Gender Inequality Index rankings also presented greater gender differences.ConclusionGiven that girls are overall less active than boys across the globe, the findings of this study reinforce that macro- and micro-level changes should be actively sought if we aim to increase population levels of PA in adolescents and promote equity in PA.  相似文献   

10.
Abstract

The purpose of this study was to establish whether an accumulated brisk walking programme, performed during the school day, is effective in changing body composition in primary school children aged 5–11 years. Altogether, 152 participants (79 boys and 73 girls) took part in this repeated-measures intervention study, divided into groups of walkers and controls. The walkers took part in the intervention during school time, which involved brisk walking around the school grounds for 15 min in the morning and afternoon, at least three times a week for 15 weeks. This represented an additional 90 min of moderate physical activity per week. The controls undertook their usual school day activities. Pre- and post-intervention anthropometric and body composition measures were taken. Body fat (?1.95 ± 2.6%) and fat mass (?0.49 ± 1.0 kg) were significantly reduced in the walkers after the intervention, whereas the controls showed no significant changes in these measures. Our results show that regular accumulated bouts of brisk walking during the school day can positively affect body composition in primary school children.  相似文献   

11.
Abstract

The goals of this study were (1) to describe and compare levels of physical activity (PA), assessed by accelerometry, of adolescents in two close Spanish and French cities according to gender and period of the week and (2) to assess, with reference to country and gender, the extent to which international PA guidelines were fulfilled. The PA of 401 adolescents (53.37% females) from France and Spain (55.72% French) aged 14.45±0.67 years was assessed with GT3X accelerometers for seven consecutive days to evaluate their habitual levels of moderate to vigorous physical activity (MVPA). Data collection took place from September to December 2010 in six public and state schools in France and Spain. There were significant differences in MVPA in terms of country, gender and period of the week. Spanish adolescents were more active than French adolescents, boys were more active than girls and MVPA was higher on weekdays than at weekends. French girls showed the lowest level of PA. Only 35.9% of the whole sample met the guidelines for PA in both countries. Governments of relevant countries, especially France, should adopt PA promotion policies targeted at adolescents in order to enhance their compliance with PA guidelines.  相似文献   

12.
This study assessed the associations between these factors in a random sample of Czech families with preschool and school-aged children. A nationally representative sample comprised 185 families with preschool children and 649 families with school-aged children (dyads; both parents and child n?=?365, mother and child n?=?730, and father and child n?=?469). The participants wore Yamax Digiwalker SW-200 pedometers at least four weekdays and both weekend days and completed family logbooks (anthropometric parameters, daily step counts (SC), and screen time (ST)). When a parent (fathers at weekends and mothers both on weekdays and at weekends) achieved 10,000 SC per day, their children were also significantly (OR?=?2.93–6.06, 95% CI?=?2.02–9.26) more likely to meet the daily SC recommendation. On the contrary, the involvement of fathers in organized leisure-time PA reduced their children's odds of meeting the SC recommendation on weekdays (OR?=?0.53, 95% CI?=?0.31–0.89) and at weekends (OR?=?0.41, 95% CI?=?0.24–0.72). The excessive ST of parents at weekends reduced the odds of their children meeting the SC recommendation (mother–child dyads: OR?=?0.44, 95% CI?=?0.26–0.72; father–child dyads: OR?=?0.63, 95% CI?=?0.37–1.06). High levels of parents’ PA contribute to the achievement of the recommended daily PA in children on weekdays and at weekends. Excessive weekend ST of parents reduces their odds of their children achieving the recommended daily PA; however, the influence of parents’ PA on their children’s achieving the recommended daily PA is stronger than the inhibitory effect of ST.  相似文献   

13.
Abstract

Exponential fatigue curves for dynamic work of the forearm muscles were obtained from 200 boys arid girls ranging from 8 through 17 years of age. The fatigue parameters analyzed in relation to initial strength were fatigable strength, steady-state equilibrium strength, and relative rate of strength loss per contraction. Older children were stronger and exhibited greater fatigue. When their strength loss and steady-state levels were considered in relation to their initial strength-capacity, there were no age differences in fatigability, and sex differences were either absent or very small. At age eight, boys and girls had equal rates of strength loss per muscle contraction. Older boys, since they exerted more strength initially, tended to reach the fatigue level more rapidly than younger children. Older girls reached their fatigue level more slowly.  相似文献   

14.
ABSTRACT

No study has investigated secular changes in both total steps and moderate-to-vigorous physical activity (MVPA) among Japanese children. This study examined the secular changes of total steps and MVPA among fourth-grade students in Japan in 2003/2004 and 2016/2017. It was performed at a school in Okayama Prefecture in Japan. A total of 452 participants (226 boys and 226 girls; mean age, 9.6 ± 0.5 years) participated in the study. We measured total steps and MVPA of the participants by using the same methods in 2003/2004 and 2016/2017. An uniaxial accelerometer was used to measure total steps and MVPA. On weekdays and weekends, the total steps and MVPA were lowered by approximately 1,000–3,000 steps/day and 10 min/day, respectively, in boys and by 1,000 steps/day and 5 min/day, respectively, in girls in 2016/2017 in comparison to 2003/2004. In both boys and girls, the percentage of children meeting 60 minutes/day of MVPA decreased in 2016/2017(weekdays: boys 21.8%, girls 6.0%; weekends: boys 3.8%, girls 4.1%) compared with 2003/2004 (weekdays: boys 48.2%, girls 11.6%; weekends: boys 7.8%, girls 7.6%). In conclusion, the results demonstrated that total steps and MVPA of fourth-grade students in Japan were lower in 2016/2017 than in 2003/2004.  相似文献   

15.
In outdoor activities, it seems reasonable that the longer children spend in spontaneous physical activity (PA), the higher the probability of being active. Indeed, the time spent outdoor has been identified as a variable consistently associated with the children’s PA. Outdoor playing, such as the organized sports practice, appears associated with healthier lifestyle standards. All the recommendations mention the importance of increasing daily PA practice in children and teenagers, but few studies highlight the relationship between outdoor play and the recommended PA levels. The purpose of this study is to investigate the relationships between the frequency of outdoor play, the frequency of the organized sports practice, and the compliance of the recommendations for PA practice in children in the inner city area of Porto. The sample of this study is composed of 422 individuals (mean age of 11.6 years). Two hundred and twenty-five of them were girls and 197 were boys from the sixth grade (elementary schools located in the inner city area of Porto). PA was objectively evaluated using accelerometers. Participants reported frequency of participation in different PA contexts, such as sports practice and outdoor play. The results show a predictor effect of participating in sports three or more times per week on compliance of PA guidelines.

In conclusion, organized sports practice seems more effective than outdoor play to reach the recommended levels of PA in children.  相似文献   

16.
ABSTRACT

Developing Physical Literacy (PL) in children is considered a promising concept for establishing active lifestyle habits; yet research evidence is scarce. This study aimed at comprehensively assessing PL in 8-12-year-old Greek children. For that purpose, the Canadian Assessment of Physical Literacy (CAPL-2) was administered to 715 children (M age = 10.2, SD = 1.3 years). Analyses of variance were applied on participants’ total, domain and individual measures scores, examining potential gender and age differences; whereas, participants’ classification and proportion across CAPL-2 interpretive categories were computed. Results revealed that there were no practically important differences (η2 < .14) between boys and girls or younger (grades 3 & 4) and older children (grades 5 & 6). Greek children presented insufficient levels of PL (their total score classified them into “progressing” PL level). CAPL-2 domains and individual measures scores showed that participants were highly motivated and felt confident to participate in physical activity (PA); however, they exhibited low PA as well as unsatisfactory physical competence, knowledge, and understanding to value and take responsibility for engagement in PA. Although further research is needed for a comprehensive picture of PL correlates, our findings highlight the need for providing Greek children with ample opportunities to enhance their PL.  相似文献   

17.
BackgroundThe coronavirus disease-2019 (COVID-19) pandemic and national lockdowns took away opportunities for children to be physically active. This study aimed to determine the effect of the COVID-19 lockdown on accelerometer-assessed physical activity (PA) in children in Wales.MethodsEight hundred participants (8–18 years old), stratified by sex, age, and socio-economic status, wore Axivity AX3 accelerometers for 7 days in February 2021, during the lockdown, and in May 2021, while in school. Raw accelerometer data were processed in R-package GGIR, and cut-point data, average acceleration (AvAcc), intensity gradient, and the acceleration above which the most active X minutes are accumulated (MX) metrics were extracted. Linear mixed models were used to assess the influence of time-point, sex, age, and socioeconomic status (SES) on PA.ResultsDuring lockdown, moderate-to-vigorous PA was 38.4 ± 24.3 min/day; sedentary time was 849.4 ± 196.6 min/day; mean ± SD. PA levels increased significantly upon return to school (all variables p < 0.001). While there were no sex differences during lockdown (p = 0.233), girls engaged in significantly less moderate-to-vigorous PA than boys once back in school (p < 0.001). Furthermore, boys had more favorable intensity profiles than girls (intensity gradient: p < 0.001), regardless of time-point. PA levels decreased with age at both time-points; upper secondary school girls were the least active group, with an average M30 of 195.2 mg (while in school).ConclusionThe lockdown affected boys more than girls, as reflected by the disappearance of the typical sex difference in PA levels during lockdown, although these were re-established on return to school. Upper secondary school (especially girls) might need specific COVID-recovery intervention.  相似文献   

18.
This study compared performances and motor delay classifications for the Test of Gross Motor Development-2nd edition (TGMD-2) and the Körperkoordinationstest Für Kinder (KTK) in a sample of 424 healthy children (47% girls) between 5 and 10 years of age. Low-to-moderate correlations (r range = 0.34–0.52) were found between assessments across age. In general, both boys and girls demonstrated higher raw scores across age groups. However, percentile scores indicated younger children outperformed older children, denoting a normative percentile-based decrease in motor competence (MC) in the older age groups. In total, the TGMD-2 and KTK classified 39.4% and 18.4% children, respectively, as demonstrating very low MC (percentile ≤5). In conclusion, the TGMD-2 classified significantly more children with motor delays than the KTK and the differences between children’s motor skill classification levels by these assessments became greater as the age groups increased. Therefore, the TGMD-2 may demonstrate more susceptibility to sociocultural influences and be more influenced by cumulative motor experiences throughout childhood. Low-to-moderate correlations between assessments also suggest the TGMD-2 and KTK may measure different aspects of MC. As such, it may be important to use multiple assessments to comprehensively assess motor competence.  相似文献   

19.
BackgroundPuberty is a critical time in the development of overweight and obesity. The aim of this study was to examine relationships between measures of adiposity, cardiovascular fitness, and biomarkers of cardiovascular disease risk in adolescents.MethodsIn a cross-sectional study design, 129 girls and 95 boys aged 12.9–14.4 years at various stages of puberty were included, along with their mothers (n = 217) and fathers (n = 207). Anthropometric assessments of adiposity were made, along with cardiovascular physical fitness, using the 20-m shuttle run test, and biomarkers associated with cardiovascular risk, including glucose, insulin, triglyceride, fibrinogen, and C-reactive protein (CRP) concentrations.ResultsWaist-to-height ratio values were similar in boys and girls and correlated positively with diastolic blood pressure, insulin, triglyceride, fibrinogen, and CRP concentrations, and inversely with cardiovascular fitness scores. Skinfold thickness measurements were higher in girls. High-molecular-weight adiponectin concentrations were lower in boys than girls, particularly in late puberty, and CRP levels were higher. Cardiovascular fitness, maternal body mass index (BMI), and paternal BMI contributed independently to the variance in waist measurements in girls and boys. Gender, triceps skinfold thickness, and weight-to-height ratio, but not parental BMI, contributed independently to the variance in cardiovascular fitness.ConclusionThere is a relationship between measures of adolescent adiposity and parental weight that involves factors other than cardiovascular fitness. Adolescent boys have relatively more abdominal fat than girls and a tendency to have a proinflammatory profile of biomarkers. These observations suggest that family and social environmental interventions are best undertaken earlier in childhood, particularly among boys.  相似文献   

20.
Purpose:The aim of the present study was to analyze the associations of youths' sedentary behavior(SB) with parents' and siblings' SB and physical activity(PA),as well as the associations of youths' coparticipation with parents,siblings,and friends in PA and SB with youths' SB.Methods:The sample consisted of 1543 youths(12.02±2.51 years;788 boys) enrolled in the baseline cohort of the UP&DOWN study.SB was assessed by accelerometry and questionnaire.Participants reported the time spent by their parents and siblings watching television,playing videogames,surfing the Internet,sitting/resting,and doing PA.Further,participants reported coparticipation with parents,siblings,and friends in these activities.Linear mixed models,including school and city as random effects,were performed.Results:Parents' television time was positively associated with youths' screen-based SB.Coparticipation with friends in playing videogames(in boys) and in surfing the Internet(in girls) showed a positive association with screen-based SB and a negative association with educational-based SB.Moreover,coparticipation with siblings and friends in PA was inversely associated with accelerometer-based SB in boys and girls.Conclusion:Our results emphasize the important role of social modeling in the development of sedentary lifestyles in youths.Interventions aimed at reducing health risk behaviors in youths could be more effective if they are oriented from a social perspective that involves their families and networks of their closest friends.  相似文献   

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