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1.
J Res Adolesc ; 34(1): 192-204, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38287685

RESUMEN

This study applied the time-varying effect model (TVEM) to data from the National Longitudinal Study of Adolescent to Adult Health to explore how self-esteem mediated age-varying associations of closeness to mother and father and their child's sexual behavior through adolescence and emerging adulthood. Paternal closeness is associated with lesser odds of sexual behaviors for both female and male adolescents until age 20, whereas maternal closeness only predicts for female adolescents between ages 13 and 15. Self-esteem mediated the association between mother closeness and multiple partners in male adolescents between ages 14.5 and 16.5. Fathers have an impact on adolescent sexual behavior across adolescence and emerging adulthood, while mothers' roles are more important for female adolescents in early adolescence.


Asunto(s)
Padres , Autoimagen , Adulto , Niño , Humanos , Masculino , Adolescente , Femenino , Adulto Joven , Estudios Longitudinales , Padre , Conducta Sexual
2.
ACS Appl Mater Interfaces ; 12(46): 51616-51627, 2020 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-33164486

RESUMEN

It has been proved that bulk single crystals of a halide perovskite behave much better than its polycrystalline counterparts in multiple application scenarios. Thus, the growth of large-sized and high-quality single crystals is significant to guarantee their ultimate device performances. Here, based on our recently invented settled temperature and controlled antisolvent diffusion system, improvements achieved in this work include the following: (1) We modified the growth system to optimize the control over both mass and heat transport to alleviate defect formation. State-of-the-art-quality MAPbBr3 crystals were grown, and from the bulk crystals, differently oriented crystalline wafers were fabricated with the full width at half-maximum of X-ray rocking curves of 40-86 arcsec. (2) The optical band gaps revealed no anisotropy on differently oriented wafers, whereas the refractive index and extinction coefficient exhibited obvious anisotropy. (3) Angle-resolved polarized Raman spectra demonstrate distinct in-plane anisotropy on (100) and (110) wafers but not on the (111) wafer. The equilibrium MA+ orientations are deduced to adopt the <111> direction with the antiparallel MA+ orientation between adjacent domains. (4) Radiation detectors fabricated on differently oriented wafers proved photoresponse anisotropy to both visible and X-ray radiation, following a general order of (100) > (110) > (111). Because anisotropy is an inevitable issue for various applications employing crystalline materials, this study, based on the clarification of the debatable intrinsic dipole configuration in the pseudocubic crystal lattice, will provide quantitative information on physicochemical property anisotropy and subsequently facilitate optimization of device performance referring to crystal orientations of halide perovskite crystals.

3.
Nat Commun ; 10(1): 761, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30770817

RESUMEN

Organic cocrystals possess valuable properties owing to the synergistic effect of the individual components. However, the growth of molecular cocrystals is still in its primary stage. Here we develop a microspacing in-air sublimation method to grow organic cocrystals, and furthermore to realize morphology control on them, which is essential for structure-property relations. A series of polycyclic aromatic hydrocarbon (PAH)‒1,2,4,5-tetracyanobenzene (TCNB) complexes cocrystals are grown directly on the substrate, with the morphology tunable from 1D needle-like to 2D plate-like on demand. Spatially resolved photoluminescence spectra analyses on different cocrystals display morphology dependent and anisotropic optical waveguiding properties. In situ observation and energy calculations of the crystallization processes reveal the formation mechanism being from a competition between growth kinetics-defined crystal habit and the thermodynamics driving force. This growth technique may serve the future demand for tunable morphology organic cocrystals in different functional applications.

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