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Single cell oil (SCO) prepared from biodiesel-derived crude glycerol (BCG) and lignocellulosic biomass (LCB) via oleaginous yeasts is an intriguing alternative precursor of biodiesel. Here, a novel strategy combining alkaline BCG pretreated corn stover and dilute acid pretreated water hyacinth for SCO overproduction was developed. The mixed pretreatment liquors (MPLs) were naturally neutralized and adjusted to a proper carbon-to-nitrogen ratio beneficial for SCO overproduction by Cutaneotrichosporon oleaginosum. The toxicity of inhibitors was relieved by dilution detoxification. The enzymatic hydrolysate of solid fractions was suitable for SCO production either separately or simultaneously with MPLs. Fed-batch fermentation of the MPLs resulted in high cell mass, SCO content, and SCO titer of 80.7 g/L, 75.7 %, and 61.1 g/L, respectively. The fatty acid profiles of SCOs implied high-quality biodiesel characteristics. This study offers a novel BCG&LCB-to-SCO route integrating BCG-based pretreatment and BCG/LCB hydrolysates co-utilization, which provides a cost-effective technical route for micro-biodiesel production.
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Basidiomycota , Eichhornia , Glicerol , Biocombustibles , Zea mays , Lípidos , Levaduras , Fermentación , Ácidos , BiomasaRESUMEN
Pretreatment is a prerequisite to tackle the issue of biomass recalcitrance, which is the major hindrance of lignocellulose-to-sugars routes. In the present study, a novel combination of dilute sulfuric acid (dilute-H2SO4) with Tween 80 pretreatment of corn stover (CS) was developed to significantly enhance the enzyme digestibility. Strong synergistic effects of H2SO4 and Tween 80 for simultaneously eliminating hemicellulose and lignin and significantly promoting saccharification yield were observed. A response surface optimization realized the maximum monomeric sugar yield of 95.06% at 120 °C for 1.4 h with 0.75 wt% of H2SO4 and 73.92 wt% of Tween 80. The excellent enzyme susceptibility of pretreated CS was explained by their physical and chemical characteristics via SEM, XRD, and FITR. The repeatedly recovered pretreatment liquor exerted highly-effective reusability in the subsequent pretreatments for at least four cycles. This strategy offers a highly-efficient and practical pretreatment strategy, which provides valuable information for the lignocellulose-to-sugars routes.
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Lignina , Polisorbatos , Zea mays , Hidrólisis , AzúcaresRESUMEN
Objective: The purpose of this study was to explore the relationship between exercise adherence and suicidal ideation in college students, as well as the mediating role of meaning in life and internet addiction. Methods: A total of 1925 college students (Mage = 19.51 years, SDage = 2.393 years) were recruited by stratified cluster sampling method in Zhaoqing University, among which 890 were males and 1,035 were females. Exercise adherence, meaning in life, internet addiction and suicidal ideation were assessed by using standard scales. Data were analyzed by Pearson Correlation Analysis, and bias-correction percentile Bootstrap method. Results: (1) There is a significant correlation between exercise adherence, meaning in life, internet addiction and suicide ideation; (2) meaning in life plays a significant mediating role between exercise adherence and suicidal ideation; internet addiction plays a significant mediating role between exercise adherence and suicidal ideation; meaning in life and internet addiction play a chain mediating role between exercise adherence and suicide ideation. Conclusion: Exercise adherence can not only directly predict college students' suicidal ideation, but also indirectly predict college students' suicidal ideation through the independent mediation and chain mediation of meaning in life and internet addiction.
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Objective: This study explores the relationship between physical exercise and school adaptation of junior middle school students and constructs a chain intermediary model through the intermediary role of psychological resilience and sports learning motivation. Methods: Using the stratified cluster sampling method, 930 junior middle school students in Anhui Province were measured in group psychology by using the physical exercise rating scale, adolescent psychological resilience scale, physical learning motivation scale and school adaptation scale. The statistical software SPSS 23.0 and process plug-in were used for statistical processing, and the common method deviation test was carried out by Harman single-factor control method. Finally, the bootstrap sampling test method and process plug-in were used to test the significance of intermediary effect. Results: (1) The direct prediction effect of physical exercise on school adaptation is remarkable (t = 4.60, p < 0.01); (2) psychological resilience and sports learning motivation are the intermediary variables of the relationship between physical exercise and school adaptation; (3) psychological resilience and sports learning motivation play a chain mediation role in the relationship between physical exercise and school adaptation. The intermediary effect is composed of three indirect effects: physical exercise â psychological resilience â school adaptation (95% Cl: 0.004, 0.041), physical exercise â physical learning motivation â school adaptation (95% Cl:0.019, 0.065), physical exercise â psychological resilience â physical learning motivation â school adaptation (95% Cl:0.002, 0.021). Conclusions: Physical exercise can directly improve the school adaptation of junior middle school students, which can also affect junior middle school students' school adaptation indirectly through psychological resilience or sports learning motivation, and it can influence school adaptation through the chain mediation of psychological resilience and sports learning motivation.
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Purpose: This study examined the relationship between physical exercise (PE) and prosocial behavior (PSB) and constructed a chain mediation model through the mediating effect of physical education learning motivation (PELM) and emotional intelligence (EI). Methods: Through the stratified random sampling, 1053 students (average age = 14 years, SD = 0.96 years) that complied with the requirements were surveyed from Henan Province in China. PE, EI, PELM, and PSB were assessed using standard scales. For data analysis, Pearson's correlation analysis, structural equation model test, and bias-corrected percentile Bootstrap method were carried out in turn. Results: (1) There was a significant positive correlation between PE and PSB (r = 0.137), and the direct path between PE and PSB was significant (ß = 0.09, t = 4.73, p < 0.01); (2) PE can positively predict EI (ß= 0.08, t = 5.27, p < 0.01) and PELM (ß= 0.04, t = 2.07, p < 0.05), EI can significantly and positively PSB (ß= 0.67, t = 22.12, p < 0.01), PELM can significantly and positively predict PSB (ß= 0.05, t =2.20, p<0.05); (3) EI and physical learning motivation play a significant intermediary role between PE and PSB. The mediating effect consists of three indirect effects: PE â EI â PSB (the mediating effect value is 0.055), PE â PELM â PSB (the mediating effect value is 0.002), PE â EI â PELM â PSB (the mediating effect value is 0.002); (4) The chain mediation effect is significant in girls, but not in boys. Conclusion: (1) PE can positively predict PSB. (2) EI and PELM had significant mediating effects between PE and PSB, including single mediating effects of EI and PELM and chain mediating effects of EI-PELM; (3) There are gender differences in the chain mediation effect.
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Objective: This study explores the relationship between exercise intention and exercise behavior and constructs a chain mediating model through the mediating effect of implementation intention and self-identity. Method: Through the stratified cluster sampling method, 1,573 junior school students (with an average age of 13.71 ± 0.891 years) were evaluated by the exercise intention scale, the implementation intention scale, the self-identity scale, and the physical exercise grade scale. For data analysis, the common method deviation test, Pearson correlation analysis, and Model 6 in the SPSS macro program compiled by Hayes for the chain mediating test were conducted. Results: (1) There is a marked correlation between positive exercise intention and exercise behavior (r = 0.345, p < 0.01), and exercise intention has a significant effect on the direct path of exercise behavior (ß = 0.162, t = 12.355, p < 0.01). (2) Exercise intention can positively predict implementation intention (ß = 0.219, t = 10.006, p < 0.01) and self-identity (ß = 0.160, t = 16.159, p < 0.01); implementation intention can significantly and positively predict exercise behavior (ß = 0.230, t = 12.742, p < 0.01),and self-identity can significantly and positively predict exercise behavior (ß = 0.273, t = 7.911, p < 0.01). (3) Implementation intention and self-identity play a significant mediating role between exercise intention and exercise behavior. The mediating effect consists of three indirect effects: exercise intention â implementation intention â exercise behavior (the mediating effect value is 0.050), exercise intention â self-identity â exercise behavior (the mediating effect value is 0.044), and exercise intention âimplementation intention â self-identity â exercise behavior (the mediating effect value is 0.017). Conclusion: (1) Exercise intention can significantly and positively predict exercise behavior. (2) Implementation intention and self-identity exert a significant mediating effect between exercise intention and exercise behavior, including the separate mediating effect of implementation intention and self-identity, as well as the chain mediating effect of implementation intention and self-identity.
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This study aims to contribute to understanding the mechanisms underlying the association between empowering motivational climate in physical education and social adaptation among senior high school students, and has important implications for interventions that aim at improving social adaptation among senior high school students. Through the quota sampling, 1,526 students (average age = 17 years, SD = 0.714 years) who came from Anhui Province and met the requirements participated and completed the Empowering Motivational Climate Questionnaire in Physical Education (EMCQ-PE), the Physical Education Engagement Scale (PEES-S), the Emotional Intelligence Scale (EIS) (Chinese version), and the Adolescent Social Adaptation Assessment Questionnaire (ASAAQ). For data analysis, Pearson's correlation analysis, structural equation model test, and bias-corrected percentile Bootstrap method were carried out in turn. The results showed that empowering motivational climate in physical education positively predicted social adaptation (ß = 0.282, p < 0.01), empowering motivational climate in physical education positively predicted physical education engagement and emotional intelligence (ß = 0.169, p < 0.01; ß = 0.690, p < 0.01), physical education engagement positively predicted emotional intelligence and social adaptation (ß = 0.591, p < 0.01; ß = 0.058, p < 0.05), and emotional intelligence positively predicted social adaptation (ß = 0.365, p < 0.01). Physical education engagement and emotional intelligence played a mediating role in empowering motivational climate in physical education and social adaptation, with a total mediating effect value of 0.251. This study shows that empowering motivational climate in physical education not only directly predicts social adaptation but also indirectly predicts social adaptation through the chain mediating effect of physical education engagement and emotional intelligence.
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This study aims to explore the relationship between physical exercise (PE), self-control (SC), physical exercise atmosphere (PEA), and mobile phone addiction tendency (MPAT) among Chinese university students. Through the quota sampling, 1,433 students complied with the requirements were surveyed from 10 universities in China. PE, SC, PEA, and MPAT were assessed using standard scales. For data analysis, common method deviation test, mean number, standard deviation, correlation analysis and structural equation model analysis were carried out in turn. The results showed PE and MPAT were negatively related (r = -0.158, p < 0.05); PE significantly positively predicted SC (ß = 0.082, t = 3.748, p < 0.01), and SC significantly negatively predicted MPAT (ß = -0.743, t = -19.929, p < 0.01). Bootstrap method was used to test the mediating effect of SC. The results showed that 95% confidence interval did not include 0. After adding the mediating variable of SC, PE did not significantly negatively predict the tendency of MPAT (ß = -0.027, t = -1.257, p > 0.05). The interaction item PEA and SC could significantly positively predict the tendency of MPAT (ß = 0.165, t = 2.545, p < 0.05). In the high PEA group, SC had a significant negative predictive effect on the tendency of MPAT (ß = -0.665, t = -14.408, p < 0.01); However, in the low PEA group, the negative predictive effect was stronger (ß = -0.834, t = -15.015, p < 0.01). The present study shows that PE significantly negatively predicted the tendency of MPAT, and SC played a complete mediating role in the relationship between PE and MPAT; The second half of the indirect effect of PE and MPAT was regulated by the PEA. The PEA will enhance the influence of SC on MPAT, but the high PEA will increase the level of MPAT of individuals at a very high level of SC.
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Objective: Based on the theory of planned behavior, this study introduced personality traits and exercise-induced feelings and other third variables, aiming to explore the mechanism of personality traits and exercise-induced feelings between exercise intention and exercise behavior, and explore the internal mechanism of promoting exercise behavior of junior high school students. Methods: This research adopts the Exercise Intention Questionnaire, Simple Big Five Personality Scale, Exercise-induced Feeling Inventory and Exercise Rating Scale, from the three cities of Anhui province 1,166 junior high school students selected from the group psychological measurement, and uses the SPSS23.0 and Process plug-in exercise intention in exercise behavior analysis of the direct and indirect effect. Results: The results showed that: (1) Exercise intention significantly positively predicted exercise behavior (ß = 0.265, t = 4.261, p < 0.01). (2) The moderating effect of openness personality between exercise intention and exercise behavior was significant (ß = 0.093, t = 4.431, p < 0.01). (3) Exercise-induced feelings has a significant mediating effect on the relationship between exercise intention and exercise behavior regulated by openness personality. Conclusion: Exercise intention can effectively predict exercise behavior, and the prediction level is affected by openness personality, and the moderating effect of openness personality is partially realized through the mediating variable of exercise-induced feelings.
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Objective: This study aims to help understand the mechanism behind the relationship between physical exercise and the subjective well-being among Chinese junior high school students, and it is of great significance for the intervention measures to improve the subjective well-being of junior high school students. Methods: Using stratified cluster sampling method, 1,510 junior high school students (727 males and 783 females) were measured by physical exercise rating scale, perceived social support scale, physical exercise self-efficacy scale, and subjective well-being scale. For data analysis, Pearson's correlation analysis, structural equation model test, and bias-corrected percentile Bootstrap method were carried out in turn. Results: Common method biases can be accepted in this study. (1) There is a positive correlation between physical exercise and subjective well-being, and physical exercise has a significant predictive effect on subjective well-being(ß = 0.367 t = 9.415 p < 0.01); (2) Perceived social support partially mediated the relationship between physical exercise and subjective well-being (ß = 0.08, t = 3.083, p < 0.01), and its effect ratio is 78.047%; (3) Physical exercise self-efficacy plays a partial mediating role between physical exercise and subjective well-being(ß = 0.181, t = 5.132, p < 0.01), accounting for 50.632%; (4) The chain mediating effect of perceived social support and physical exercise self-efficacy was significant (the mediating effect value was 0.028), and the effect amount was 7.629%. Conclusion: (1) Physical exercise can significantly positively predict the subjective well-being of junior high school students; (2) Physical exercise can also indirectly affect the subjective well-being of junior high school students through the mediating effect of perceived social support and physical exercise self-efficacy. The intermediary effect includes three paths, namely, the individual intermediary effect of perceived social support and physical exercise self-efficacy and the chain intermediary effect of perceived social support physical exercise self-efficacy.
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Objective: This study aimed to contribute to understanding the mechanisms underlying the association between empowering motivational climate in physical education and social responsibility among high school students, and have important implications for interventions aimed at improving social responsibility among high school students. Methods: Through the quota sampling, 802 students (average age = 17 years, SD = 0.97 years) that complied with the requirements were surveyed from Anhui Province in China. Empowering motivational climate in physical education, social responsibility, interpersonal disturbance, and general self-efficacy were assessed using standard scales. For data analysis, Pearson's correlation analysis, structural equation model test, and bias-corrected percentile Bootstrap method were carried out in turn. Results: (1) Common method biases can be accepted in this study, and the correlation among empowering motivational climate in physical education, social responsibility, interpersonal disturbance, and general self-efficacy are all significant; (2)Empowering motivational climate in physical education, interpersonal disturbance and general self-efficacy can all predict social responsibility significantly; (3) Structural equation modeling indicates good fit: χ2/df = 2.86, RMESA = 0.068, CFI = 0.92, NNFI = 0.91, NFI = 0.90, GFI = 0.93. It indicates that interpersonal disturbance and general self-efficacy can play mediating roles between empowering motivational climate in physical education and social responsibility, respectively. After that, interpersonal disturbance as well as general self-efficacy in turn plays the chain mediating effect in the relationship between empowering motivational climate in physical education and social responsibility. The effect size of the mediating effect of interpersonal disturbance and general self-efficacy in the relationship between empowering motivational climate in physical education and social responsibility is 0.048 and 0.148, respectively, and the effect size of the chain mediating effect is 0.031. Conclusion: Empowering motivational climate in physical education not only has a direct effect on social responsibility among high school students, but also influences social responsibility by the chain mediating effect of interpersonal disturbance and general self-efficacy.