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Allana G. LeBlanc Peter T. Katzmarzyk Tiago V. Barreira Stephanie T. Broyles Jean-Philippe Chaput Timothy S. Church Mikael Fogelholm Deirdre M. Harrington Gang Hu Rebecca Kuriyan Anura Kurpad Estelle V. Lambert Carol Maher José Maia Victor Matsudo Timothy Olds Vincent Onywera Olga L. Sarmiento Martyn Standage Catrine Tudor-Locke Pei Zhao Mark S. Tremblay ISCOLE Research Group 《PloS one》2015,10(6)
Purpose
Previously, studies examining correlates of sedentary behavior have been limited by small sample size, restricted geographic area, and little socio-cultural variability. Further, few studies have examined correlates of total sedentary time (SED) and screen time (ST) in the same population. This study aimed to investigate correlates of SED and ST in children around the world.Methods
The sample included 5,844 children (45.6% boys, mean age = 10.4 years) from study sites in Australia, Brazil, Canada, China, Colombia, Finland, India, Kenya, Portugal, South Africa, the United Kingdom, and the United States. Child- and parent-reported behavioral, household, and neighborhood characteristics and directly measured anthropometric and accelerometer data were obtained. Twenty-one potential correlates of SED and ST were examined using multilevel models, adjusting for sex, age, and highest parental education, with school and study site as random effects. Variables that were moderately associated with SED and/or ST in univariate analyses (p<0.10) were included in the final models. Variables that remained significant in the final models (p<0.05) were considered correlates of SED and/or ST.Results
Children averaged 8.6 hours of daily SED, and 54.2% of children failed to meet ST guidelines. In all study sites, boys reported higher ST, were less likely to meet ST guidelines, and had higher BMI z-scores than girls. In 9 of 12 sites, girls engaged in significantly more SED than boys. Common correlates of higher SED and ST included poor weight status, not meeting physical activity guidelines, and having a TV or a computer in the bedroom.Conclusions
In this global sample many common correlates of SED and ST were identified, some of which are easily modifiable (e.g., removing TV from the bedroom), and others that may require more intense behavioral interventions (e.g., increasing physical activity). Future work should incorporate these findings into the development of culturally meaningful public health messages. 相似文献136.
137.
Deirdre P. Cronin-Fenton Mariann Christensen Timothy L. Lash Thomas P. Ahern Lars Pedersen Jens Peter Garne Marianne Ewertz Herman Autrup Henrik T. S?rensen Stephen Hamilton-Dutoit 《PloS one》2014,9(1)
Background
Manganese superoxide dismutase (MnSOD) inhibits oxidative damage and cancer therapy effectiveness. A polymorphism in its encoding gene (SOD2: Val16Ala rs4880) may confer poorer breast cancer survival, but data are inconsistent. We examined the association of SOD2 genotype and breast cancer recurrence (BCR) among patients treated with cyclophosphamide-based chemotherapy (Cyclo). We compared our findings with published studies using meta-analyses.Methods
We conducted a population-based case-control study of BCR among women in Jutland, Denmark. Subjects were diagnosed with non-metastatic breast cancer from 1990–2001, received adjuvant Cyclo, and were registered in the Danish Breast Cancer Cooperative Group. We identified 118 patients with BCR and 213 matched breast cancer controls. We genotyped SOD2 and used conditional logistic regression to compute the odds ratio (OR) and associated 95% confidence intervals (95% CI) of BCR. We used random-effects meta-analytic models to evaluate the association of SOD2 polymorphisms and BCR.Results
The frequency of the SOD2-Ala allele was 70% in cases versus 71% in controls; 40% versus 44% were heterozygotes, and 30% versus 25% were homozygotes, respectively. Heterozygote and homozygote carriers of the Ala allele had no increased rate of BCR (OR = 1.1, 95%CI = 0.65, 2.0, and OR = 0.87, 95%CI = 0.47, 1.6, respectively). Five studies informed the meta-analytic models; summary estimates associating BCR for homozygote, or any inheritance of the variant Ala allele were 1.18 (95%CI = 0.74, 1.88), and 1.18, (95%CI = 0.91, 1.54), respectively.Conclusion
Our findings do not suggest that MnSOD enzymatic activity, as measured by SOD2 genotype, affects rates of BCR among patients treated with Cyclo. 相似文献138.
Deirdre Russell-Bowie 《Arts Education Policy Review》2013,114(4):163-173
The arts are an integral and important component of our everyday lives. As such, they need to be a vital part of our children's education. However, this has rarely been the case in Australian state primary schools over the past two hundred years. This article explores the history of the arts in Australian state primary schools since the colonization of Australia to the present day. I examine how arts education has been subject to policy changes and inquiries that have not seemed to significantly benefit the arts in our schools and that have at times seemed to marginalize the arts in primary schools. The article concludes with a challenge to arts educators and other stakeholders to develop and implement a long-term approach to policy and practice to ensure that the arts serve as an “Ode to Joy” rather than dissolving into “Sounds of Silence.” 相似文献
139.
With the successful development of organic/polymeric light emitting diodes, many organic and polymeric fluorophores with high quantum efficiencies and optical stability were synthesized. However, most of these materials which have excellent optical properties are insoluble in water, limiting their applications in biological fields. Herein, we used micelles formed from an amino-group-containing poly(ε-caprolactone)-block-poly(ethylene glycol) (PCL-b-PEG-NH2) to incorporate a hydrophobic blue emitter oligofluorene (OF) to enable its application in biological conditions. Although OF is completely insoluble in water, it was successfully transferred into aqueous solutions with a good retention of its photophysical properties. OF exhibited a high quantum efficiency of 0.84 in a typical organic solvent of tetrahydrofuran (THF). In addition, OF also showed a good quantum efficiency of 0.46 after being encapsulated into micelles. Two cells lines, human glioblastoma (U87MG) and esophagus premalignant (CP-A), were used to study the cellular internalization of the OF incorporated micelles. Results showed that the hydrophobic OF was located in the cytoplasm, which was confirmed by co-staining the cells with nucleic acid specific SYTO 9, lysosome specific LysoTracker Red®, and mitochondria specific MitoTracker Red. MTT assay indicated non-toxicity of the OF-incorporated micelles. This study will broaden the application of hydrophobic functional organic compounds, oligomers, and polymers with good optical properties to enable their applications in biological research fields. 相似文献
140.
Deirdre McKay 《Visual Anthropology: Published in cooperation with the Commission on Visual Anthropology》2013,26(4):381-392
This article explores the role of photographs in shaping the social selves of Filipino temporary labor migrants. Examining the production of photographic self-images by Filipino migrants in Hong Kong and their reception in the Philippines, I show how people deploy photography as a technology to bring into being their desired future selves. By making present ghosts of the future, photographs of the self shape distinctive translocal subjectivities. 相似文献