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Spent graphite, as the main component of retired batteries, have attracted plenty of attentions. Although a series of recycling strategies are proposed, they still suffer from high cost of regeneration and large CO2 emission, mainly ascribed to the full-recovery of surface and internal phase at ultra-high temperature. However, the existing of suitable internal defects is conductive to their energy-storage abilities. Herein, with the introduction of Fe-based catalysts, spent graphite is successfully repaired at low temperature with the tailored surface traits, including conductivities, isotropy and so on. As Li-storage anodes, all of samples can display a capacity of 340 mAh g-1 above at 1.0 C after 200 cycles. At high rate 5.0 C, their capacity can be also kept ≈300 mAh g-1, and remained ≈233 mAh g-1 even after 1000 cycles. Assisted by electrochemical and kinetic behaviors, their cycling traits with dynamic surface transformations are detailed explored, including activated/fading mechanism, Li-depositions forming etc. Moreover, the calculated constant time of as-optimized regenerated sample is ≈3.0 × 10-4 s, further revealing the importance of surface designing. Therefore, the work is expected to shed light on their energy-storage behaviors, and offer low-temperature regenerated strategies of spent graphite with high value.
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Captured by high theoretical capacity and low-cost, Sodium-Sulfur (Na-S) batteries have been deemed as promising energy-storage systems. However, their electrochemical properties, containing both cycling and rate properties, still suffer from the notorious "shuttle effect" of polysulfide. Herein, through the effective regulation of pore sizes, a series of S/SiO2 cathode materials are obtained. Benefitting from the abundant pore channels of SiO2 particles, the sulfur loading is as high as 76.3%. Importantly, a suitable pore size can lead to adequate reaction and rapid diffusion behaviors, resulting in excellent electrochemical performances. Specifically, at 2.0 A g-1, the initial capacity of the as-optimized sample can be up to 1370.6 mAh g-1. Surprisingly, even after 1050 cycles, it could achieve a high reversible capacity of 1280.8 mAh g-1 with an attenuation rate of 0.089%. At 5.0 A g-1, after 500 cycles, the capacity can still remain ≈ 1132.6 mAh g-1 (capacity retention rate, 97.5%). Given this, the work is anticipated to offer an effective strategy for advanced electrodes for Na-S batteries.
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BACKGROUND: This study is based on the biosocial model of nonsuicidal self-injury (NSSI), to explore the effects of cumulative ecological risk on adolescents' NSSI, the mediating effect of depression between cumulative ecological risk and adolescents' NSSI, and the moderating role of impulsiveness in this mediating pathway. METHODS: A total of 16 508 adolescents, with 7903 males (47.9%), participated in the study and completed the Cumulative Ecological Risk Questionnaire, the Short Form of the Center for Epidemiological Studies Depression Scale, the Impulsiveness assessment, and the Nonsuicidal Self-Injury Scale. RESULTS: (1) There was a significant positive correlation between cumulative ecological risk, depression, impulsiveness, and NSSI; (2) cumulative ecological risk significantly predicted adolescents' NSSI; (3) depression had a mediating effect between cumulative ecological risk and adolescents' NSSI; and (4) impulsiveness moderated both the effects of cumulative ecological risk on adolescents' depression and NSSI and the effects of depression on NSSI in adolescents. CONCLUSIONS: Impulsiveness and depression are risk factors for adolescent NSSI and play a crucial role between cumulative ecological risk and NSSI in adolescents.
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Depressão , Comportamento Autodestrutivo , Masculino , Humanos , Adolescente , Inquéritos e Questionários , Fatores de RiscoRESUMO
TEOSINTE BRANCHED 1/CYCLOIDEA/PROLIFERATING CELL FACTOR 1 (TCP) transcription factors control multiple aspects of growth and development in various plant species. However, few genes were reported to be directly targeted and regulated by them through their specific binding sites, and then uncover their functions in plants. A consensus DNA-binding site motif of TCP2 was identified by random binding site selection (RBSS). DNA recognized by TCP2 contained the motif G(G/T)GGNCC(A/C), which showed high consistency with motifs bound by other TCP domain proteins. Consequently, this motif was regarded as the specific DNA-binding sites of TCP2. Circadian clock associated 1 (CCA1) and EARLY FLOWERING 3 (ELF3) were subsequently considered as potential target genes owing to the containing of the similar TCP2 binding sites or core binding sites GGNCC and found to be positively regulated by TCP2 via DNA binding. Phenotype analysis results showed that mutation and over-expression of TCP2 resulted in variations in leaf morphogenesis, especially the double or triple mutations of TCP2, 4 and 10. Mutations in TCPs caused late flowering. Finally, TCP2 was shown to influence hypocotyl elongation by mediating the jasmonate signaling pathway. Overall, these results provide a basis for future studies aimed at distinguishing the target genes of TCP2 and elucidating the important roles of TCP2 in plant growth and development.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Sítios de Ligação/genética , Sequência Consenso/genética , DNA de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Sequência de Bases , Ciclopentanos/metabolismo , Flores/fisiologia , Regulação da Expressão Gênica de Plantas , Hipocótilo/crescimento & desenvolvimento , Morfogênese/genética , Mutação/genética , Oxilipinas/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Ligação Proteica , Domínios Proteicos , Transdução de Sinais , Fatores de Tempo , Fatores de Transcrição/química , Fatores de Transcrição/genéticaRESUMO
The construction of a smart city puts forward new requirements for lighting systems, such as variable color temperature adapting to environment and low energy consumption. We introduce a variable color temperature laser lighting system that produces uniform light with minimum energy. The color temperature is controlled by tri-color RGB diode lasers, and uniform lighting is achieved by microlens arrays. Tri-color diode lasers with wavelengths of 650, 556, and 450 nm are used as the lighting sources, and the white light laser output is achieved by combining the three beams. The color temperature is controlled by changing the power ratio of each lighting source. Finally, the homogenization of laser energy is regulated by the microlens arrays, and the energy uniformity reaches 91.1%. Moreover, we do an experiment to compare LED street lighting and laser street lighting, finding that the street lighting system with this design can increase the energy utilization rate by 113.33%, and the color temperature of the car headlamps with this design can be changed according to the environment. Therefore, this laser lighting system is an effective solution for modern smart lighting systems and energy saving, which have vast application.
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This paper is concerned with a kind of Bobwhite quail population model x n + 1 = A + B x n + x n x n - 1 x n - 2 , n = 0 , 1 , ⯠, where the parameters and initial values are positive parabolic fuzzy numbers. According to g-division of fuzzy sets and based on the symmetrical parabolic fuzzy numbers, the conditional stability of this model is proved. Besides the existence, boundedness and persistence of its unique positive fuzzy solution. When some fuzzy stability conditions are satisfied, the model evolution exhibits oscillations with return to a fixed fuzzy equilibrium no matter what the initial value is. This phenomena provided a vivid counterexample to Allee effect in density-dependent populations of organisms. As a supplement, two numerical examples with data-table are interspersed to illustrate the effectiveness. Our findings have been verified precise with collected northern bobwhite data in Texas, and will help to form some efficient density estimates for wildlife populations of universal applications.
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Lógica Fuzzy , Animais , Dinâmica Populacional , Colinus , Modelos BiológicosRESUMO
Background: Based on the gene-environment interaction paradigm, this study explored the effect of peer relationships on adolescent loneliness and the role of psychological resilience and the oxytocin receptor gene (OXTR). Methods: A survey was conducted in a sample of 619 adolescents, and their oral cells were collected for DNA extraction and genotyping. Results: The results showed that (1) both peer relationships and psychological resilience significantly affected adolescent loneliness; (2) psychological resilience partially mediated the relationship between peer relationships and loneliness in adolescents; (3) OXTR gene rs53576 polymorphism moderated both the first and second half of the indirect pathway of the mediation model. Specifically, carriers of the rs53576 polymorphism A/A genotype showed a significantly enhanced effect of peer relationships on adolescent psychological resilience, while carriers of the rs53576 polymorphism G/G genotype showed a significantly enhanced effect of psychological resilience on adolescent loneliness. Conclusion: These findings helped elucidate the developmental mechanisms of adolescent loneliness in terms of peer relationships, psychological resilience, and OXTR gene polymorphisms.
A moderated mediation effects analysis was conducted to investigate the effect of peer relationships on adolescent loneliness and the role of psychological resilience and the oxytocin receptor gene (OXTR). The results revealed psychological resilience partially mediated the relationship between peer relationships and loneliness in adolescents; OXTR gene rs53576 polymorphism moderated both the first and second half of the indirect pathway of the mediation model. These findings helped elucidate the developmental mechanisms of adolescent loneliness in terms of peer relationships, psychological resilience, and OXTR gene polymorphisms.
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Background: Various psychological theories suggest that a supportive family environment protects the mental health of young adults during stressful life events. However, evidence is limited regarding the protective role of family support during a major public health crisis. Objective: To examine the role of family functioning on mental health among Chinese college students during first stage of the COVID-19 pandemic. Methods: Between January-March 2020, 1,555 college students (44% female, on average 19 years old) from five Chinese universities participated. Participants rated their family functioning on the Family APGAR Index and their mental health on the Psychological Questionnaires for Emergent Events of Public Health, measuring depression, neurasthenia, fear, obsessive-anxiety and hypochondriasis. Results: Better family functioning was associated with having fewer psychological symptoms. In addition, we identified three mental health profiles related to the severity across the psychological symptoms: Low-level, medium-level and high-level symptom clusters. Latent profile analysis showed that as family function improved, students were, respectively, 16 to 24% more likely to be in the low-level symptom group, compared to being in the medium symptom group or the high-level symptom group. Conclusion: These results support the notion that family support may act as a psychological buffer for young adults during a large-scale public health crisis like the COVID-19 pandemic.
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COVID-19 , Saúde Mental , Estudantes , Humanos , COVID-19/psicologia , COVID-19/epidemiologia , Feminino , Masculino , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Adulto Jovem , Universidades , China/epidemiologia , Saúde Mental/estatística & dados numéricos , Inquéritos e Questionários , Adulto , SARS-CoV-2 , Estresse Psicológico/psicologia , Família/psicologia , Adolescente , Pandemias , Relações Familiares/psicologiaRESUMO
A chemical-physical investigation proved that the loss of active Li represents the main mechanism of capacity-fading in spent LiFePO4. Given this, functional Li2CuO2-coated separators were fabricated from spent Cu foil and found to contribute to the regeneration of spent LiFePO4 in a full-cell system. This study presents a novel method for cathode/Cu foil recovery.
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This study aimed to explore the relationship between life events and non-suicidal self-injury (NSSI) in college students, as well as the mediating effect of sleep disturbances and psychotic-like experiences (PLEs). After excluding invalid questionnaires, 5,754 were retained, and the valid efficiency was 75.94%. The subjects were aged 16 to 29 years (M = 19.166; SD = 1.392), with 1,969 males (34.22%) and 3,785 females (65.78%). Life events, sleep disturbances, PLEs, and NSSI were assessed using standard scales. Data were analyzed by Pearson Correlation Analysis and bias-correction percentile Bootstrap method. The results show that (1) life events were significant positive predictors of NSSI, sleep disturbances, and PLEs; (2) sleep disturbances, PLEs, and the chain mediation between the two, were mediators between life events and NSSI. Life events are thus shown to be an important external factor influencing NSSI in university students, and this process is mediated through sleep disturbances, PLEs, and the chain between the two. Interventions for NSSI can therefore be made by improving college students' sleep quality and reducing PLEs.
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Double-sided microlens arrays (DSMLAs) include combinations of two single-sided MLAs to overcome positioning errors and greatly improve light transmissivity compared to other types of lenses. Precision glass molding (PGM) is used to fabricate DSMLAs, but controlling alignment errors during this process is challenging. In this paper, a mold assembly was manufactured with a novel combination of materials to improve the alignment accuracy of mold cores during PGM by using the nonlinear thermal expansion characteristics of the various materials to improve the DSMLA alignment accuracy. By establishing a mathematical model of the DSMLA alignment error and a thermal expansion model of the mold-sleeve pair, the relationship between the maximum alignment error of the DSMLA and the mold-sleeve gap was determined. This research provides a method to optimize the mold-sleeve gap and minimize the alignment error of the DSMLA. The measured DSMLA alignment error was 10.56 µm, which is similar to the predicted maximum alignment error. Optical measurements showed that the uniformity of the homogenized beam spot was 97.81%, and the effective homogeneous area accounted for 91.66% of the total area. This proposed method provides a novel strategy to improve the performance of DSMLAs.
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BACKGROUND: Research suggests that genetic variants linked to serotonin functioning moderate the association between environmental stressors and depressive symptoms, but examining gene-environment interactions with single polymorphisms limits power. METHODS: A multilocus genetic profile score (MGPS) approach to measuring serotonergic multilocus genetic variation and examined interactions with interpersonal relationship, insomnia with depressive symptoms as outcomes in an adolescent sample (average age = 14.15 ± 0.63 years since first measurement; range: 13 to 15). RESULTS: (1) interpersonal relationship predicted adolescent depressive symptoms; (2) insomnia mediated the effect of interpersonal relationships on adolescent depressive symptoms; (3) the THP2 gene rs4570625 polymorphism G allele was a key risk factor for depressive symptom, and the MGPS moderated the effects of teacher-student relationship and insomnia on adolescent depressive symptom. Specifically, as the MGPS increased, the effects of insomnia on adolescent depressive symptom were enhanced; further, when the MGPS score increased, the effect of teacher-student relationship on depression showed a similar phenomenon with an increased slope and enhanced prediction; and (4) the results of sensitivity analysis showed that multilocus genetic interaction with the environment had a better explanatory power and stability for depression than single polymorphism studies. CONCLUSION: MGPS provides substantial power to examine gene-environmental interactions linked to affective outcomes among adolescents.
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Depressão , Distúrbios do Início e da Manutenção do Sono , Adolescente , Humanos , Depressão/genética , Relações Interpessoais , Alelos , Polimorfismo GenéticoRESUMO
This study designed and prepared a new piezoelectric catalytic nanomaterial, Bi2WO6/ZnSnO3, and applied it in piezocatalytic water purification. Results indicated that the composite had superior piezocatalytic efficiency and stability in rhodamine B (RhB) degradation under ultrasonic vibration. The Bi2WO6/ZnSnO3 sample with 10% Bi2WO6 had the optimum activity with a degradation rate of 2.15 h-1, which was 7.4 and 11.3 times that of ZnSnO3 and Bi2WO6, respectively. Various characterizations were conducted to study the morphology, structure, and piezoelectric properties of the Bi2WO6/ZnSnO3 composites and reveal the reasons for their improved piezocatalytic performance. Results showed that ZnSnO3 cubes were dispersed throughout the surface of Bi2WO6 nanosheets, which enhanced the specific surface area and facilitated the piezocatalytic reaction. Additionally, type-II heterojunction structures formed at the contact interface of Bi2WO6 and ZnSnO3, driving the migration of piezoelectric-induced electrons and holes. Accordingly, the separation efficiency of charge carriers improved, and the piezoelectric catalytic activity was significantly enhanced. This study may provide a potential composite catalyst and a promising idea for the design of highly efficient piezoelectric catalyst.
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Ultrassom , Vibração , Ondas Ultrassônicas , CatáliseRESUMO
Due to their low cost and high stability, sodium-ion batteries have been increasingly studied. However, their further development is limited by the relative energy density, resulting in the search for high-capacity anodes. FeSe2 displays high conductivity and capacity but still suffers from sluggish kinetics and serious volume expansion. Herein, through sacrificial template methods, a series of sphere-like FeSe2-carbon composites are successfully prepared, displaying uniform carbon coatings and interfacial chemical FeOC bonds. Moreover, benefiting from the unique traits of precursor and acid treatment, rich structural voids are prepared, effectively alleviating volume expansion. Utilized as anodes of sodium-ion batteries, the optimized sample displays considerable capacity, achieving 462.9 mAh g-1, with 88.75% coulombic efficiency at 1.0 A g-1. Even at 5.0 A g-1, their capacity can be kept at approximately 318.8 mAh g-1, while the stable cycling can be prolonged to 200 cycles above. Supported by the detailed kinetic analysis, it can be noted that the existing chemical bonds facilitate the fast shuttling of ions at the interface, and the enhanced surface/near-surface properties are further vitrified. Given this, the work is expected to offer valuable insights for the rational design of metal-based samples toward advanced sodium-storage materials.
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Magnetostrictive alloys have attracted increasing attention in biomedical applications because of the ability to generate reversible deformation in the presence of external magnetic fields. This review focuses on the advances in magnetostrictive alloys and their biomedical applications. The theories of magnetostriction are systematically summarized. The different types of magnetostrictive alloys and their preparation methods are also reviewed in detail. The magnetostrictive strains and phase compositions of typical magnetostrictive alloys, including iron based, rare-earth based and ferrite materials, are presented. Besides, a variety of approaches to preparing rods, blocks and films of magnetostriction materials, as well as the corresponding methods and setups for magnetostriction measurement, are summarized and discussed. Moreover, the interactions between magnetostrictive alloys and cells are analyzed and emphasis is placed on the transduction and transformation process of mechanochemical signals induced by magnetostriction. The latest applications of magnetostrictive alloys in remote microactuators, magnetic field sensors, wireless implantable devices and biodegradable implants are also reviewed. Furthermore, future research directions of magnetostrictive alloys are prospected with focus on their potential applications in remote cell actuation and bone repair.
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OBJECTIVE: To investigate the relationship between family functioning and suicidal ideation among adolescents. METHOD: A total of 4515 junior and senior high school students were assessed using the Family APGAR, the Depressive Symptom Index-Suicidality Subscale, the Defeat Scale, and the Chinese Meaning in Life Questionnaire. RESULTS: This study found pairwise correlations between suicidal ideation, family functioning, defeat, and meaning in life. Specifically, family functioning was an influencing factor of adolescent suicidal ideation, and defeat was a mediator of the relationship between family functioning and adolescent suicidal ideation; meaning in life was found to be a moderator of the first half of the mediation process by defeat, that is, it moderated the influence of family functioning on adolescent defeat. CONCLUSIONS: This study demonstrated that the relationship between family functioning and adolescent suicidal ideation, as well as the influence of defeat and meaning in life on this relationship, constituted a moderated intermediary model. This finding has both theoretical and practical value for the implementation of a psychosocial model of adolescent suicide prevention and intervention.
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Estudantes , Ideação Suicida , Adolescente , Humanos , Estudantes/psicologia , Inquéritos e Questionários , Povo AsiáticoRESUMO
Owing to its fascinating properties (such as high theoretical specific capacity and considerable conductivity), nickel sulfide (NiS) was investigated comprehensively as an anode material in sodium-ion batteries. However, they still suffered from volume expansion and sluggish kinetics, resulting in serious cycle capabilities. Herein, through controlling the kind of molten salts (Na2SO4, NaCl, and Na2CO3) in salt melt synthesis (SMS), a series of NiS with an N, S-codoped carbon layer was successfully prepared, accompanied with different morphologies and structures (earthworm-like belts and triangular and spherical particles). Tailored by the ionic strength and viscosity of molten salts, the as-prepared samples displayed different crystallization behaviors, bringing about a difference in electrochemical performance. As earthworm-like NiS@C was explored as an anode material for SIBs, an initial capacity of 712.5 mAh g-1 at 0.5 A g-1 could be obtained, and it still kept 527.4 mAh g-1 after 100 cycles. Even at 2.0 A g-1, a capacity of 508.6 mAh g-1 could be achieved. Meanwhile, with the assistance of detailed kinetic analysis, the rapid diffusion behaviors of Na+ and redox reaction mechanisms of as-fabricated samples were proven for the enhanced electrochemical properties. Given this, this work is expected to provide a method for designing the morphology and structure of metal sulfides, while shedding light on the orientation of fabricating advanced electrode materials for SIBs.