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1.
Org Lett ; 26(12): 2414-2419, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38489286

RESUMEN

We present an innovative photoinduced cyanoalkyl radical addition methodology using N-iminopyridinium reagents derived from cyclic ketones. Mechanistic investigations reveal the association of the excited Hantzsch ester and iminopyridinium with pyridyl radical generation. The ensuing cascade involving homolytic N-N bond and C-C bond cleavage of the pyridyl radical ultimately leads to the formation of cyanoalkyl radical species, leading to diverse Giese-type products. The method showcases versatility and synthetic utility in late-stage functionalization.

2.
Artículo en Inglés | MEDLINE | ID: mdl-32331366

RESUMEN

Background: We aimed to examine whether the Healthy Children, Healthy Families, and Healthy Communities Program, consisting of multi-level strategies for obesity prevention tailoring the context of socioeconomically vulnerable children based on an ecological perspective, would be effective on improving their healthy lifestyle behaviors and obesity status. Methods: Participants were 104 children (and 59 parents) enrolled in public welfare systems in Seoul, South Korea. Based on a cluster-randomized controlled trial (no. ISRCTN11347525), eight centers were randomly assigned to intervention (four centers, 49 children, 27 parents) versus control groups (four centers, 55 children, 32 parents). Multi-level interventions of child-, parent-, and center-level strategies were conducted for 12 weeks. Children's healthy lifestyle behaviors and obesity status were assessed as daily recommended levels and body mass index ≥85th percentile, respectively. Parents' parenting behaviors were measured by the Family Nutrition and Physical Activity scale. Results: Compared to the control group, the intervention group showed significant improvements in total composite scores of healthy-lifestyle behaviors-including 60-min of moderate physical activity-but not in obesity status among children. Moreover, the intervention group showed significant improvements in parenting behaviors among parents. Conclusion: The multi-level strategies for obesity prevention based on an ecological perspective may be effective for promoting healthy lifestyles among socioeconomically vulnerable children.


Asunto(s)
Conductas Relacionadas con la Salud , Promoción de la Salud , Obesidad Infantil , Índice de Masa Corporal , Niño , Ejercicio Físico , Femenino , Humanos , Estilo de Vida , Masculino , Padres , Obesidad Infantil/prevención & control , República de Corea , Seúl , Poblaciones Vulnerables
3.
Artículo en Inglés | MEDLINE | ID: mdl-27005654

RESUMEN

Whether adolescent overweight/obesity is linked to socioeconomic status (SES) and fruit and vegetable (F/V) intakes has not been confirmed. We aimed to determine whether there is an association between SES and adolescent overweight/obesity and to test the mediating effect of F/V intakes. This cross-sectional study included the data of 63,111 adolescents extracted from the 2013 Korea Youth Risk Behavior Web-based Survey. Overweight/obesity was defined as a body mass index ≥ 85th percentile, while F/V intakes were categorized as high (recommended levels: ≥ 1 fruit serving and ≥ 3 vegetable servings per day) versus low. Among girls, low SES (beta = 0.50, p < 0.001) and F/V intakes (beta = -0.17, p = 0.038) were both significantly associated with overweight/obesity; the former association was significantly mediated by F/V intakes (Sobel test: z = 2.00, p = 0.046). Among boys, neither SES nor F/V intakes was significantly associated with overweight/obesity. Adolescent overweight/obesity was significantly linked to low SES and F/V intakes among girls only; low SES indirectly increased the risk of overweight/obesity via low F/V intakes. Therefore, promoting F/V intakes for socially disadvantaged girls should be prioritized as a population-based strategy for preventing adolescent overweight/obesity in South Korea.


Asunto(s)
Dieta/estadística & datos numéricos , Frutas , Sobrepeso/etiología , Clase Social , Verduras , Adolescente , Estudios Transversales , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Sobrepeso/prevención & control , Obesidad Infantil/etiología , Obesidad Infantil/prevención & control , Factores Protectores , República de Corea , Factores de Riesgo
4.
J Nanosci Nanotechnol ; 14(12): 9340-5, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25971062

RESUMEN

In this work, silicon (Si) containing carbon coated core-shell nanostructures were synthesized by electrical explosion of Si wires in ethanol solution followed by high energy mechanical milling (HEMM) process. Material characterization was carried-out using transmission electron microscopy (TEM), field-emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD) analysis. HEMM led to very fine and amorphous Si particles in the presence of carbon and inactive Silicon-Carbide (SiC) matrix. These Si based nanocomposites, obtained through electrical explosion followed by HEMM (milled sample), exhibited enhanced electrochemical performance than unmilled nanocomposites, when evaluated as anode material for lithium-ion batteries (LIBs). On completion of (the) 1st cycle, milled and unmilled sample(s) showed specific discharge capacities around 825 mAh/g and 717 mAh/g, respectively. Interestingly, the coulombic efficiencies of milled and unmilled samples were 98.5% and 97% after 60th cycle respectively. The enhanced electrochemical performance is attributed to fine and amorphous Si based nanocomposite obtained through HEMM process.

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