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Schematic illustration of the preparation of dense microporous carbons. [Display omitted] • The dense microporous carbons were prepared by a universal and facile strategy of pre-oxidation carbonization–activation. • The prepared microporous carbons not only possess well-developed porous structure but also have a large packing density. • The optimum microporous carbon shows high specific capacitance and excellent rate performance. • This work offers a good cost-efficiency strategy to prepare electrode materials with prospects for practical applications. The compact carbon materials with huge specific surface area (SSA) and proper pore structure are highly desirable towards high-performance supercapacitors at the cell level. However, to well balance of porosity and density is still an on-going task. Herein, a universal and facile strategy of pre-oxidation–carbonization–activation is employed to prepare the dense microporous carbons from coal tar pitch. The optimized sample POCA800 not only possesses a well-developed porous structure with the SSA of 2142 m2 g−1 and total pore volume (V t) of 1.540 cm3 g−1, but also exhibits a high packing density of 0.58 g cm−3 and proper graphitization. Owing to these advantages, POCA800 electrode at areal mass loading of 10 mg cm−2 shows a high specific capacitance of 300.8 F g−1 (174.5 F cm−3) at 0.5 A g−1 and good rate performance. The POCA800 based symmetrical supercapacitor with a total mass loading of 20 mg cm−2 displays a large energy density of 8.07 Wh kg−1 at 125 W kg−1 and remarkable cycling durability. It is revealed that the prepared density microporous carbons are promising for practical applications. [ABSTRACT FROM AUTHOR]

Schematic illustration of the preparation of porous carbons. [Display omitted] • The porous carbons with controllable architecture were fabricated by a dual-role KCl-assisted activation method. • KCl not only serves as an auxiliary template but also contributes to an enhancement in the melting of K 2 CO 3. • The prepared porous carbons possess well-developed pore structure and excellent electrochemical performance. • This work paves a path to prepare porous carbons via an environment-friendly and cost-effective route for supercapacitors. Preparation of high-performance electrode materials in a low-cost and simple way is of great significance for the application and development of supercapacitors. Herein, a dual-role KCl-assisted KOH activation method with low KOH consumption was employed to fabricate porous carbons with controllable architecture, using the coal liquefaction residue (CLR) as the raw material. It is indicated that KCl not only serves as an auxiliary template for pore-forming but also contributes to an enhancement in the melting of K 2 CO 3 , an intermediate of KOH activation, resulting in an improvement in the efficiency of KOH activation. As a consequence, the prepared samples possess highly developed pore structure even at a low KOH consumption, which endow them with excellent capacitive performance. The as-fabricated optimal porous carbon (LR-KPC-4) displays a maximum specific capacitance of 375 F g−1 at 0.5 A/g and superior rate capacity, which are much better than those of the porous carbon prepared without KCl. The fabricated symmetric supercapacitor shows a high specific capacitance of 256 F g−1 at 0.5 A/g, energy density of 8.9 Wh kg−1 at 125 W kg−1 and great cycling stability. This work demonstrates a facile strategy to efficiently convert CLR into porous carbons for high-performance supercapacitors. Meanwhile, it paves a promising way for value-added utilization of CLR. [ABSTRACT FROM AUTHOR]

Depression is a major challenge in the global healthy aging process, and exploring the key factors of depression in urban and rural older adults is essential for differentiated and precise interventions. To explore the urban-rural differences and key influencing factors of depressive symptoms among Chinese older adults. The data of 5267 older adults were obtained from the China Health and Retirement Longitudinal Survey (CHARLS2018). Random forest model and logistic regression were used to analyze the key factors influencing depressive symptoms 19 variables. The detection rate of depressive symptoms in older adults was 31.0 %, with 22.3 % and 34.8 % in urban and rural areas, respectively. Education, self-rated health, self-rated pain, and self-rated vision were common factors. Physical activity (OR = 0.716 for Moderate PA), social activity (OR = 0.671 for social activity), and self-rated hearing (OR = 0.602 for good) were key factors specific to urban older adults, and alcohol consumption (OR = 0.716 for drinking more than once a month) and marital status (OR = 0.689 for cohabitation) were key factors specific to depressive symptoms in rural older adults (all P < 0.05). Cross-sectional data cannot reflect dynamic processes among variables; The cultural background might affect the cross-cultural validity of the study. The key factors of depressive symptoms among older adults in urban and rural areas differed, which provides priority and references for differential prevention and precise intervention of depressive symptoms to promote the process of healthy aging. • Education, self-rated health, pain, and vision are common factors that influence depressive symptoms in older adults. • Physical activity, social activity, and self-rated hearing were key factors specific to urban older adults. • Alcohol consumption and marital status were key factors specific to rural older adults. • The combination of random forest and logistic regression achieves the importance measurement and analysis of factors. [ABSTRACT FROM AUTHOR]

Background: Both depression and anxiety are worldwide burden that is not being abated with our current knowledge and treatment of the condition. Numerous clinical trials have supported that physical activity (PA) can reduce the depression and anxiety in adolescents, but little is known about its mechanism of action. Therefore, the study objectives were to explore the potential relationship between physical activity and depression and anxiety from the perspective of body image and body mass index (BMI), and to provide an important reference for future self-esteem education and health promotion intervention. Methods: The participants in this study were 251 Chinese college students between 17 and 22 years old. Participants completed the International Physical Activity Questionnaire-Short Form (IPAQ-SF), the Body Image Questionnaire (BIQ), the Self-rating Depression Scale (SDS) and the Self-rating Anxiety Scale (SAS). A descriptive and correlational approach was used, using the PROCESS macro for Statistical Package for the Social Sciences (SPSS). Results: (1) Physical activity was significantly negatively correlated with both depression and anxiety (t = -0.216, p < 0.001; t = -0.184, p < 0.01). (2) Body image had a significant moderating effect on the relationship between physical activity and anxiety among college students, but there was no moderating effect between depression and physical activity. BMI has no moderating effect on the two interrelationships. Conclusion: There is only body image that moderates the relationship between anxiety and physical activity. [ABSTRACT FROM AUTHOR]

Background: Both depression and anxiety are worldwide burden that is not being abated with our current knowledge and treatment of the condition. Numerous clinical trials have supported that physical activity (PA) can reduce the depression and anxiety in adolescents, but little is known about its mechanism of action. Therefore, the study objectives were to explore the potential relationship between physical activity and depression and anxiety from the perspective of body image and body mass index (BMI), and to provide an important reference for future self-esteem education and health promotion intervention. Methods: The participants in this study were 251 Chinese college students between 17 and 22 years old. Participants completed the International Physical Activity Questionnaire-Short Form (IPAQ-SF), the Body Image Questionnaire (BIQ), the Self-rating Depression Scale (SDS) and the Self-rating Anxiety Scale (SAS). A descriptive and correlational approach was used, using the PROCESS macro for Statistical Package for the Social Sciences (SPSS). Results: (1) Physical activity was significantly negatively correlated with both depression and anxiety (t = -0.216, p < 0.001; t = -0.184, p < 0.01). (2) Body image had a significant moderating effect on the relationship between physical activity and anxiety among college students, but there was no moderating effect between depression and physical activity. BMI has no moderating effect on the two interrelationships. Conclusion: There is only body image that moderates the relationship between anxiety and physical activity. [ABSTRACT FROM AUTHOR]

Longer quiet eye (QE) periods are associated with better performance across a range of targeting and interceptive tasks. However, the direction of this relationship is still unclear. The two studies presented aimed to narrow this knowledge gap by experimentally manipulating QE duration-by delaying its onset or by truncating its offset-in an aiming interceptive task. In Experiment 1, the early trajectory was occluded, causing significantly shorter QE durations and worse subsequent performance. In Experiment 2, both early and/or late trajectory were occluded. Performance was degraded by the occlusion of either early or late information, and the worst performance occurred when both the early and late trajectory were occluded. Taken together, the results suggest that QE is not a by-product of performance but instead plays a causal role in supporting the interception of a moving target through a combination of preprogramming and online control processes. [ABSTRACT FROM AUTHOR]