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Despite the well-established link between children's executive function and behavioral adjustment, it remains unclear whether the hot and cool aspects of executive function are uniquely associated with children's behavioral problems. Using longitudinal data spanning in the grade school (N = 1,140), this study aimed to examine whether hot and cool executive function skills may be uniquely related to the development of behavioral problems. Hot and cool executive function skills were measured with tasks, standardized tests, and questionnaires at 54 months and in the first grade, respectively. Internalizing and externalizing problems were evaluated by teachers using questionnaires throughout the grade school. The results indicated that, independent of each other, hot and cool executive function skills were uniquely and negatively related to the development of internalizing and externalizing problems over time at the between-individual level, adjusting for within-individual fluctuations. Moreover, internalizing and externalizing problems were positively related at the between-individual level across the grade school. Findings provide needed evidence to clarify the relations between hot and cool executive function and children's behavioral problems, emphasizing the importance of both aspects of executive function in understanding the development of behavioral problems in school-age children.
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BACKGROUND: Early life adversity (ELA) increases the risk of cardiovascular diseases through dysregulation of cardiovascular stress responses manifested by either exaggerated or blunted reactivity. The catechol-O-methyltransferase (COMT) gene rs4680 polymorphism has been identified in gene-environment interaction (G×E) studies to explain individual differences in the effects of ELA on physiological stress responses. However, little is known about whether ELA interacts with COMT gene rs4680 polymorphism to affect cardiovascular responses to repeated stress exposures. OBJECTIVE: The current study examined the associations between ELA and cardiovascular responses to repeated stress exposures, and the moderating role of COMT rs4680 polymorphism in these associations. METHODS: The childhood trauma questionnaire (CTQ) was administered to 359 junior school students who underwent a two-successive stress exposures protocol with continuous cardiovascular monitoring [heart rate (HR) and systolic and diastolic blood pressure (SBP, DBP)] across four laboratory phases, and their saliva samples for deoxyribonucleic acid (DNA) genotyping were collected. RESULTS: ELA was associated with blunted HR reactivity to the first and second stress exposures, blunted SBP reactivity to the first stress exposure, and attenuated SBP habituation to repeated stress exposures. Moreover, COMT rs4680 moderated these associations, such that the associations between ELA and blunted HR, SBP, and DBP reactivity to the first stress and disrupted DBP habituation to repeated stress exposures only existed in GA/AA genotype carriers but not in GG genotype carriers. CONCLUSIONS: These findings suggest that the A allele of COMT rs4680 is vulnerable to the negative effects of ELA on the developmental dysregulation of stress physiological systems.
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Experiencias Adversas de la Infancia , Catecol O-Metiltransferasa , Humanos , Adolescente , Catecol O-Metiltransferasa/genética , Polimorfismo Genético , Genotipo , Heterocigoto , Polimorfismo de Nucleótido SimpleRESUMEN
BACKGROUND: Childhood abuse (CA) has been considered as an environmental risk factor for the development of social anxiety symptoms. Respiratory sinus arrhythmia (RSA) is a biomarker that has been found to interact with environmental stressors to affect psychopathological symptoms. However, little is known whether RSA moderates the relationship between CA and social anxiety symptoms. OBJECTIVE: The current study aimed to examine the relationships between CA and two forms of social anxiety symptoms including social performance anxiety symptoms (SPAS) and social interaction anxiety symptoms (SIAS), and the moderating role of baseline RSA and/or RSA suppression to a social-evaluative stress in these links. PARTICIPANTS AND SETTING: A total of 157 Chinese undergraduate students (Mage = 18.96, SD = 0.85, 85 % females) participated in this study. METHOD: Participants completed the short form of Childhood Trauma Questionnaire, Social Phobia Scale and Social Interaction Anxiety Scale to assess CA, SPAS and SIAS, and then underwent a social stress protocol (a public speech task) during which their baseline RSA and stress induced RSA were obtained. RESULTS: CA was positively correlated with SPAS but was not correlated with SIAS. RSA suppression to social stress moderated the associations between CA and two forms of social anxiety symptoms, such that CA was positively associated with SPAS and SIAS among individuals with blunted RSA suppression, but not among those with greater RSA suppression. CONCLUSIONS: Greater social stress RSA suppression as a better physiological regulation marker might ameliorate the negative effect of CA on social anxiety symptoms.
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Arritmia Sinusal Respiratoria , Ansiedad , Niño , Miedo , Femenino , Humanos , Masculino , Estrés Psicológico , Estudiantes , Adulto JovenRESUMEN
In this study, zinc-gallium oxynitrides with a Zn:Ga mole ratio of 1:1 [(GaN)0.5(ZnO)0.5] were synthesized from a Zn/Ga/CO3 layered double hydroxide (LDH) precursor. The microstructure and photoactivity of the (GaN)0.5(ZnO)0.5 particles were tuned by adjusting the nitridation conditions of the LDH. It is revealed that the quantity of the LDH, or, equivalently, the partial pressure of the water during nitridation, plays a pivotal role in the defect structure of the obtained oxynitrides. A reduction in the quantity of the LDH precursor can effectively suppress the formation of defects including Ga(Zn)-O bonding, bulk anion vacancies, and surface-deposited Ga/ON···VGa complexes, leading to a better charge-separation efficiency for the photogenerated electron-hole pairs in the oxynitride. Furthermore, a suitable introduction of methane during nitridation would not only increase the crystallinity of the bulk materials but also enhance the density of the surface oxygen vacancy (VO), which would raise the charge-injection efficiency by working as an electron trap and a reaction site to form O2â¢-. O2â¢-, as well as photogenerated holes, have been proven to be the dominant active species for the photodegradation of phenol. 25CH4-ZnGaNO, with the lowest density of bulk defects and the highest density of surface VO, exhibited the best photoactivity under visible-light irradiation for the photodegradation of Rhodamine B and phenol. The obtained surface-VO-rich (GaN)0.5(ZnO)0.5 particles can be applied as a high-performance visible-light-driven photocatalyst in the photodegradation of organic pollutants.
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InxGa1-xN nanowires (NWs) have drawn great attentions for their applications in optoelectronic and energy conversion devices. Compared to conventional substrates, metal substrates can offer InxGa1-xN NW devices with better thermal conductivity, electric conductivity, and mechanic flexibility. In this article, InxGa1-xN NWs were successfully grown on the surface of a tantalum (Ta) substrate via vapor-liquid-solid chemical vapor deposition (VLS-CVD), as characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), scanning and transmission electron microscope (STEM), and photoluminescence spectroscopy (PL). It was found that the surface pretreatment of Ta and the composition of metallic catalysts played important roles in the formation of NWs. A dimpled nitrided Ta surface combined with a catalyst of nickle is suitable for VLS-CVD growth of the NWs. The obtained InxGa1-xN NWs grew along the [1100] direction with the presence of basal stacking faults and an enriched indium composition of ~3 at.%. The successful VLS-CVD preparation of InxGa1-xN nanowires on Ta substrates could pave the way for the large-scale manufacture of optoelectronic devices in a more cost-effective way.
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Methane-based nitridation was employed to produce wurtzite zinc-gallium oxynitride (ZnGaNO) photocatalyst particles using Zn/Ga/CO3 layered double hydroxides (LDHs) as precursor. Introduction of methane to nitridation would promote the formation of Zn-O bonding and suppress shallow acceptor complexes such as V(Zn)-Ga(Zn) and Ga-Oi in ZnGaNO particles. On the other hand, high flow rate of methane would induce breaking of Ga-N bonding and enhance surface deposition of metallic Ga atoms. After loading with Rh and RuO2, ZnGaNO particles had free electron density in an order of S50 > S20 > S90 > S0, which correlated well with their photocatalytic performance upon visible-light irradiation. The best performance of the loaded S50 was ascribed to the relatively flat surface band bending of the particle. Methane-based nitridation of Zn/Ga/CO3 LDHs would provide a new route to tune the surface chemistry of ZnGaNO and enhance the photocatalytic performance to its full potential.