Background
Learning flow is an optimal learning experience representing full engagement in one’s studies. The belief–affect–engagement model and control‐value theory suggest that positivity would be ...a motivator of learning flow, while positive affect in school would be a mediator of the relation between positivity and learning flow.
Aims
The current research aimed to examine (1) the longitudinal relations among positivity, positive affect in school, and learning flow, and (2) the mediational role of positive affect in school between positivity and learning flow.
Sample and Method
A sample of 4681 Chinese elementary school students (44.9% girls; Mage = 9.87 years, SD = 0.70 at Time 1) completed reliable measures for each construct on four occasions across 2 years, using 6‐month intervals. Structural equation modelling was used for examining study hypotheses.
Results
After controlling for gender, age, and family socioeconomic status, the results showed that (1) positivity, positive affect in school, and learning flow reciprocally facilitated each other directly; (2) positive affect in school mediated the relation between positivity and later learning flow, as well as the relation between learning flow and later positivity.
Conclusions
These findings revealed that positivity, positive affect in school, and learning flow form a complex, dynamic system, suggesting that school professionals should consider monitoring and developing interventions based upon these variables as early as elementary school.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Gratitude is a human strength that is beneficial for psychosocial adjustment and academic adjustment. This study aimed to examine the (a) heterogeneity and gender differences in the developmental ...trajectories of gratitude to obtain a more nuanced understanding of the development of gratitude in children, and (b) relations between these trajectories and psychosocial adjustment, as well as academic adjustment outcomes among Chinese elementary schoolchildren to elucidate the specific benefits of gratitude for children. A sample of 715 children (45.6% girls; Mage = 8.96 years, SD = 0.76 at Time 1) from 2 Chinese elementary schools completed a packet of measures on 6 occasions across 3 years, using 6-month intervals. Latent Class Growth Modeling revealed 4 heterogeneous developmental trajectory classes of gratitude: High-Increasing, Moderate High-Decreasing, Moderate Low-Increasing, and Low-Stable. Girls were less likely than boys to fall into the Moderate Low-Increasing class or Low-Stable class in reference to the High-Increasing class. Children in the High-Increasing class and Low-Stable class showed the best and the worst psychosocial adjustment and academic adjustment, respectively. The results suggested that gratitude interventions may require adaptations for specific groups, with the Low-Stable class and Moderate High-Decreasing class needing particular attention. Meanwhile, educators aiming to increase elementary schoolchildren's psychosocial adjustment and academic adjustment should consider implementing assessment and intervention programs to promote gratitude early in the school years as well as throughout the elementary school years to prevent trajectories of negative developmental patterns.
Impact and Implications
The findings of this study suggest that there are 4 heterogeneous gratitude trajectory classes in Chinese elementary schoolchildren, with girls showing lower odds of being in the Moderate Low-Increasing or Low-Stable class than boys. This study also suggests that gratitude is positively related to children's psychosocial adjustment and academic adjustment, indicating that gratitude should be considered as an intervention target for promoting positive adjustment. Greater attention should be paid to the groups of students display decreasing or stable low gratitude.
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CEKLJ, FFLJ, NUK, ODKLJ, PEFLJ, UPUK
Bismuth‐telluride‐based solid solutions are the best commercial thermoelectric materials near room temperature. For their n‐type polycrystalline compounds, the maximum figures of merit (zTs) are ...often less than 1.0 due to the degraded carrier mobility resulting from the loss of texture. Herein, a liquid‐phase hot deformation procedure, during which the Bi2(Te,Se)3 ingots are directly hot deformed with the extrusion of liquid eutectic phase, is performed to enhance the thermoelectric performance of n‐type Bi2(Te,Se)3 alloys. The deformation‐induced dynamic recrystallization is remarkably suppressed due to the reduction of nucleation sites and the release of deformation stress by liquid phase, contributing to a weakened carrier scattering and enhanced carrier mobility. The liquid eutectic phase also facilitates the rotation of grains and enhanced (000l) texture, further improving carrier mobility. In addition, the dense dislocations and lattice distortion introduced into the matrix reduce the lattice thermal conductivity. As a result, a high zT value of 1.1 at 400 K is obtained, about 75% increment over the normal one‐step hot deformed alloys. This work not only demonstrates a simple and efficient technique for achieving superior n‐type Bi2Te3‐based materials, but also elucidates the important role of liquid eutectic phase in hot deformation.
Here, liquid‐phase hot deformation is introduced to n‐type polycrystalline Bi2Te3‐based alloys. Benefitting from the suppression of recrystallization, improvement of texture, and enhancement of phonon scattering, contributing to boosted carrier mobility and reduced lattice thermal conductivity, a peak zT ≈ 1.1 at 400 K is successfully obtained for Bi2(Te,Se)3.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Bismuth-telluride-based solid solutions are unique, commercially available thermoelectric (TE) materials near room temperature for solid-state cooling, and the zone melting (ZM) technique is commonly ...applied to grow their commercial ingots with preferred orientation. Herein, we tailor the carrier concentration of zone-melted ingots by proper doping to adjust the optimum operating temperature for both solid-state cooling and low-temperature power generation at 300–500 K. A room temperature zT of ∼ 1.2 is obtained for both p-type and n-type ingots, and a maximum zT > 1.2 at 350 K in p-type Bi0.5Sb1.5Te3 + 2 wt % Te. Moreover, zT > 1.0 between 300 and 400 K is achieved for p-type, and zT > 1.0 between 300 and 475 K for n-type counterparts. It is found that the taper of the quartz tube affects the TE properties of Bi2Te3-based alloys. The different combinations of the growth rate with temperature gradient, 8 mm/h + 25 K/cm and 25 mm/h + 40 K/cm, contribute to equally high zT. In addition, the good homogeneity in both axial and radial directions implies the high quality of the ZM ingots in this work, which is significant for industrial manufacturing. These results are favorable for TE application in low-temperature power generation and show the possibility of improving the production efficiency of commercial bismuth-telluride-based solid solutions.
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IJS, KILJ, NUK, PNG, UL, UM
Growing evidence has shown that the antioxidant diet is a protective factor against depression. However, the relationship between the Composite Dietary Antioxidant Index (CDAI), an important measure ...of antioxidant diet, and depression has received little attention. Therefore, we investigated the relationship between CDAI and depression through a cross-sectional analysis of the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2018.
The association between CDAI and depression was investigated using a weighted multiple logistic regression model with subgroup analysis. Non-linear correlations were explored using fitted smoothing curves. And we used a recursive method to figure out the turning point and build a weighted two-piece linear regression model.
In the multivariate logistic regression model with full adjustment for confounding variables, the ORs (95% CI) for the association between CDAI and depression were 0.83 (0.78, 0.88). Moreover, a non-linear association was found, with 0.16 being the inflection point. Before the inflection point, each unit increase in CDAI was associated with a 30% decrease in the risk of depression. After the inflection point, the risk of depression was found to be reduced by 11% for each unit increase. None of the interactions in all subgroup analyses were statistically significant.
Our study highlighted a negative non-linear association between CDAI and depression in a nationally representative sample of US adults. Further clinical and basic research is needed to explore their association better.
Cervical carcinoma (CC) represents a prevalent gynecological neoplasm, with a discernible rise in prevalence among younger cohorts observed in recent years. Nonetheless, the intrinsic cellular ...heterogeneity of CC remains inadequately investigated.
We utilized single-cell RNA sequencing (scRNA-seq) transcriptomic analysis to scrutinize the tumor epithelial cells derived from four specimens of cervical carcinoma (CC) patients. This method enabled the identification of pivotal subpopulations of tumor epithelial cells and elucidation of their contributions to CC progression. Subsequently, we assessed the influence of associated molecules in bulk RNA sequencing (Bulk RNA-seq) cohorts and performed cellular experiments for validation purposes.
Through our analysis, we have discerned C3 PLP2+ Tumor Epithelial Progenitor Cells as a noteworthy subpopulation in cervical carcinoma (CC), exerting a pivotal influence on the differentiation and progression of CC. We have established an independent prognostic indicator-the PLP2+ Tumor EPCs score. By stratifying patients into high and low score groups based on the median score, we have observed that the high-score group exhibits diminished survival rates compared to the low-score group. The correlations observed between these groups and immune infiltration, enriched pathways, single-nucleotide polymorphisms (SNPs), drug sensitivity, among other factors, further underscore their impact on CC prognosis. Cellular experiments have validated the significant impact of ATF6 on the proliferation and migration of CC cell lines.
This study enriches our comprehension of the determinants shaping the progression of CC, elevates cognizance of the tumor microenvironment in CC, and offers valuable insights for prospective CC therapies. These discoveries contribute to the refinement of CC diagnostics and the formulation of optimal therapeutic approaches.
Bismuth-telluride-based solid solutions are the unique thermoelectric (TE) materials near room temperature. Various approaches have been applied to enhance the thermoelectric performance, and much ...progress has been made in their p-type materials. However, for the n-type counterparts, little breakthrough has been obtained. We herein report on enhancing thermoelectric performance of n-type bismuth-telluride-based alloys by nonstoichiometry to mediate the point defects, combined with one-time hot deformation. The improved power factor of 3.3 × 10–3 W m–1 K–2 and reduced lattice thermal conductivity contribute to a high figure-of-merit, zT, of 1.2 at 450 K for n-type Bi2Te2.3Se0.69 alloys with Se deficiency. The high zT is comparable to that of Bi2Te2.3Se0.7 hot deformed three times, which is a practically complicated process. The results demonstrate that nonstoichiometry can be an effective and simple strategy in mediating intrinsic point defects and enhancing the thermoelectric performance of bismuth-telluride-based alloys.
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IJS, KILJ, NUK, PNG, UL, UM
Bismuth-telluride-based alloys are the unique thermoelectric materials for state-solid refrigeration around room temperature. For n-type polycrystalline counterparts, maximum figure of merit zTs are ...often shifted above 400 K due to the increased carrier concentration induced by the donor-like effect during the pulverization of ingots. Herein, we report a synergistic optimization procedure, combining Ag doping with hot deformation, to boost room temperature thermoelectric performance of n-type polycrystalline Bi2Te2.7Se0.3 alloys. The Ag doping optimizes the carrier concentration, contributing to an improved power factor and a reduced electrical thermal conductivity. The hot deformation process improves the carrier mobility due to the enhanced texture. As a consequence, a zT value of 1.0 at 300 K and a peak zT of 1.1 at 350 K are obtained in the twice hot deformed Ag0.011Bi2Te2.7Se0.3 alloy, which makes the n-type polycrystalline Bi2(Te,Se)3 alloys more suitable for solid-state refrigeration near room temperature.
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•A synergetic optimization procedure is performed to boost room temperature zT of n-type Bi2Te2.7Se0.3 alloy.•The carrier concentration is optimized via Ag doping and the carrier mobility is enhanced via hot deformation.•A zT value of 1.0 at 300 K and a peak zT of 1.1 at 350 K are obtained in n-type polycrystalline Bi2Te2.7Se0.3 alloy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Bismuth telluride-based alloys are the most widely used commercial thermoelectric (TE) material for room temperature refrigeration. Here, we successfully shift up the optimum figure of merit of ...n-type bismuth-telluride-based TE materials for mid-temperature power generation. SbI3 doping is used to regulate the carrier concentration and Indium alloying to increase the bandgap, suppressing the detrimental bipolar conduction in the mid-temperature range. The lattice thermal conductivity is significantly reduced due to the multiscale microstructures induced via hot deformation. As a result, a peak zT of ∼1.1 was attained at 625 K for Bi1.85In0.15Te2Se + 0.25 wt% SbI3 alloy after hot deformation, showing a great application prospect of this alloy in mid-temperature TE power generation.
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•In alloying successfully broadens the band gap of Bi2Te2Se alloys, suppressing the bipolar effect at higher temperatures.•The lattice thermal conductivity was greatly reduced by multiscale phonon scattering.•Hot deformed n-type Bi1.85In0.15Te2Se + 0.25 wt% SbI3 sample shows excellent TE performance in the range of 500–700 K.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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