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The COVID-19 crisis represents a global health concern, including mental health. Regarding the necessity to assess anxiety related to COVID-19, a scale was developed (Ahorsu et al., 2020). The goal of the present study was to validate the Fear of COVID-19 Scale (FCV-19S) in French (official language in 29 countries), and investigate its relationship with indicators of affective disturbances. The sample comprised 316 participants (271 females) recruited online during the French lockdown. They were from several regions of France. The FCV-19S underwent a forward-backward translation procedure. Its psychometric properties were evaluated with the confirmatory factor analysis (CFA). The French FCV-19S demonstrated a stable unidimensional structure with robust psychometric properties (strong internal consistency, good convergent and divergent validity, and good test-retest validity). With its robust psychometric properties in assessing the unidimensional construct of the fear of COVID-19, this scale will help to provide a better understanding of the relationship between emotions and psychological or psychiatric disorders during the pandemics in French-speaking countries.

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Personality differences are important determinants of problematic online behaviors. The purpose of the present study was to investigate the mediating role of loneliness, depression, and online gaming motives and moderating role of age on the relationship between trait emotional intelligence (EI) and Internet gaming disorder (IGD) via the construction of a multiple mediation model. A total of 478 online gamers completed a self-report online survey, including validated psychometric scales assessing the aforementioned constructs. Results indicated that trait EI was directly and indirectly associated with IGD and that the motive of escape was a partial mediator between trait EI and IGD among the total sample and adult gamers, but not among adolescents. Moreover, trait EI was associated with coping, skill development, fantasy, and recreation gaming motives only among total sample and adult gamers, and the escape motive was positively associated with IGD among total sample and adult gamers. However, among these relationships, only the association between trait EI and fantasy was significantly moderated by age group. Furthermore, the direct effect of trait EI was stronger among adolescent gamers when compared to adult gamers. Results showed that trait EI is inversely associated with IGD and affects gaming for different motives among adolescent and adult gamers.

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PURPOSE: The purpose of this study was to compare the dentin/adhesive interfacial characteristics when bonding to noncarious as well as caries-affected dentin. MATERIALS AND METHODS: Seven extracted, unerupted, third molars were sectioned into halves. Artificial caries was created on one-half of each tooth, leaving the other half as a control. Dentin surfaces were treated with UNO adhesive according to the manufacturer's instructions for the wet-bonding technique and under environmental conditions present in the oral cavity. Dentin/adhesive interface sections of each half-tooth were stained with Goldner's trichrome, a classic bone stain, and examined using light microscopy. The width of exposed collagen was measured directly from photomicrographs, and adhesive penetration was analyzed qualitatively. RESULTS: The degree and extent to which the adhesive encapsulated the demineralized dentin matrix were reflected in the color difference in the stained sections with the noncarious dentin sections showing a degree of collagen encapsulation superior to that of the caries-affected dentin sections. The overall mean widths of exposed collagen were significantly (p < or = .05) greater at the caries-affected dentin/adhesive interface, 8.6 (1.7) microm, as compared with those at the noncarious dentin/adhesive interface, 6.0 (1.5) microm. CONCLUSIONS: The morphologic characteristics of the caries-affected dentin/interface suggest an increase in the exposed collagen zone and a decrease in the quality of the adhesive infiltration when compared with noncarious dentin. The evidence suggests that dentin substrate characteristics have a significant effect on the dentin/adhesive interface structure.  相似文献   
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In cystic fibrosis (CF), perturbations of total daily energy expenditure (TDEE) may be a major determinant of altered nutrition and growth. Measurement of TDEE is problematic, though the flex-heart rate method (FHRM) provides a close estimation of TDEE, as compared to the cost-prohibitive, gold standard, the double-labeled water method, and permits estimates of the energy cost of daily activities (ECA) above resting energy expenditure (REE). We hypothesize that alterations in ECA affects TDEE in CF. PURPOSE: To measure components of TDEE in adolescents with CF and normal lung function compared with controls, and to determine whether ECA can be improved by diet and exercise. METHODS: Clinically stable CF subjects (aged 9-13, n=12) and age- and gender-matched controls (n=13) had repeated measurements of TDEE by FHRM, REE, and maximal cardiopulmonary exercise testing (CPET) during a 6-week exercise and diet program. RESULTS: While the mean REE was similar in both groups, ECA was significantly lower in CF adolescents as compared to controls (p=0.02). During CPET, maximal exercise in CF was characterized by hyperventilation, which was unrelated to ventilation-perfusion mismatching. There were no changes in REE after dietary intervention. CONCLUSION: ECA in CF adolescents with normal lung function is lower when compared to healthy controls. These findings support the hypothesis that clinically stable patients with CF have inefficient energy metabolism or alternatively conserve energy during activities of daily living.  相似文献   
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The study of brain function using MRI relies on acquisition techniques that are sensitive to different aspects of the hemodynamic response contiguous to areas of neuronal activity. For this purpose different contrasts such as arterial spin labeling (ASL) and blood oxygenation level dependent (BOLD) functional MRI techniques have been developed to investigate cerebral blood flow (CBF) and blood oxygenation, respectively. Analysis of such data typically proceeds by separate, linear modeling of the appropriate CBF or BOLD time courses. In this work an approach is developed that provides simultaneous inference on hemodynamic changes via a nonlinear physiological model of ASL data acquired at multiple echo times. Importantly, this includes a significant contribution by changes in the static magnetization, M, to the ASL signal. Inference is carried out in a Bayesian framework. This is able to extract, from dual-echo ASL data, probabilistic estimates of percentage changes of CBF, R(2) (*), and the static magnetization, M. This approach provides increased sensitivity in inferring CBF changes and reduced contamination in inferring BOLD changes when compared with general linear model approaches on single-echo ASL data. We also consider how the static magnetization, M, might be related to changes in CBV by assuming the same mechanism for water exchange as in vascular space occupancy.  相似文献   
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