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This study aims to examine the mediating effects of social problem-solving (SPS) and coping efficacy (CE), the essential internal belief sets of self-system processes, on the relationship between cumulative risk (CR) and adolescent mental health. Chinese adolescents (grades 10–11; N = 675, female = 391) completed measures assessing CR, SPS, CE, anxiety and depression, and life satisfaction at two time points. To attribute the effects of CR on mental health to the modeled processes, we applied a short-term longitudinal design to collect data on CR, the mediators, and mental health. We also used multi-group confirmatory factor analysis and multi-group structural equation modeling to test for measurement and model invariance with respect to gender before we combined and analyzed subgroup data. The results indicated that gender did not influence the strength of the associations in the models for males and females. CR predicted Time 2 anxiety and depression and life satisfaction while controlling for Time 1 mental health. Furthermore, SPS and CE and CE alone mediated the relationship between CR and prospective life satisfaction. These findings suggest that severe adversity may lead to low life satisfaction and high anxiety and depression in adolescents. Severe adversity may also lead to low life satisfaction through compromised SPS and CE. The findings provide preliminary evidence for an intervention approach targeting SPS and CE to promote adolescents' life satisfaction. [ABSTRACT FROM AUTHOR]

The thermoplastic cassava starch (TPS)/sisal fiber (SF) composites were prepared by melt blending. The effects of SF content and its surface treated by sodium hydroxide (NaOH) and silane coupling agent (KH550) on the thermal degradation behavior and structures of TPS were investigated by thermogravimetric‐mass spectrometry (TG‐MS), Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD) and nuclear magnetic resonance (NMR). The thermal decomposition temperatures of TPS/SF composites increase with the SF content. The thermal decomposition products of TPS/SF composites are mainly methane, H2O, acetylene, formaldehyde, methanol and CO2. The thermal stability of composites containing SF treated by NaOH is better than that of KH550. TPS/SF composites show A + V types crystal, and the sample containing SF treated by NaOH has the highest V type crystal. The experimental results reveal that the content and the surface of SF play an important role in the thermal stability and structures changes of TPS/SF composites. [ABSTRACT FROM AUTHOR]

Thermoplastic cassava starch (TPS)/sisal fiber (SF) composites were prepared by the melting method. The effect of SF on the retrogradation kinetics, morphology and size of spherulites, molecular interactions, short-range molecular structure, and crystal type of TPS was investigated. The results indicate that the retrogradation degree and rate of TPS increase with the addition of SF, and the spherulites become clearer and denser. The neat TPS sample forms an A-type crystal through double helix structure and a V-type crystal through single helix structure. After the addition of SF, the A-type crystal of the TPS/SF composite decreases and the V-type crystal increases. With the further increase of SF content, the TPS/SF composite mainly presents the V-type crystal. The TPS/SF composite has higher crystallinity, but smaller crystal size and interplanar spacing. The storage modulus, loss modulus, and glass transition temperature (Tg) of TPS get enhanced with the addition of SF. [ABSTRACT FROM AUTHOR]

Thermoplastic cassava starch (TPS)/silica (SiO2) composites were prepared through melt-mixing, and the effect of different SiO2 particle size (20 nm, 200 nm, and 23 µm) on the structure, morphology, and properties of TPS/SiO2 composites was investigated. TPS/SiO2 composite containing 200 nm SiO2 has the lowest plasticizing time and torque, and the highest tensile and impact strength. The 23 µm SiO2 particle has the strongest effect on promoting retrogradation of starch, while the 200 nm SiO2 particle could inhibit the retrogradation of starch. TPS/SiO2 composite containing 200 nm SiO2 has the highest thermal stability, resistant water absorption, and light transmittance. The 200 nm SiO2 particle could be uniformly and finely dispersed in the starch matrix, however 20 nm SiO2 particle easily aggregated in TPS. The spherulites size was uniform in TPS/SiO2 composite containing 200 nm SiO2. TPS/SiO2 composite indicates the mixture of A + V types of crystalline structure, and TPS/SiO2 composite containing 23 µm SiO2 had the largest crystal size. [ABSTRACT FROM AUTHOR]

By incorporating psychopathology and subjective well-being (SWB), the dual-factor model of mental health (DFM) can comprehensively measure psychological health. We examined the utility of the DFM among 1,293 Chinese adolescents (Grades 7–12). Furthermore, we examined the dynamics of mental health group membership via a two-wave longitudinal study of 531 students. SWB, psychopathology, affective self-regulatory efficacy, academic self-efficacy, and academic emotions were measured via self-report scales. Mental health group membership was determined according to combinations of high or low SWB and high or low psychopathology. The DFM was supported by our identification of its four constituent groups (i.e. complete mental health, vulnerable, troubled, and symptomatic but content). Significant group differences were found in affective self-regulatory efficacy, academic self-efficacy, and academic emotions, with clear contrasts observed between adolescents with complete mental health and their vulnerable peers, as well as between troubled adolescents and their symptomatic but content peers. Moreover, youth with complete mental health demonstrated the highest stability and troubled youth the lowest, whereas vulnerable youth had the highest rates of transitioning into both the complete mental health and troubled groups. Implications for practice are explored within the context of screening and intervention. [ABSTRACT FROM AUTHOR]