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1.
Org Lett ; 26(20): 4251-4256, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38743879

RESUMO

ß-amino sulfones are important motifs found in natural products and active pharmaceutical compounds. Herein, we report a general and highly regioselective intermolecular aminosulfonylation of alkenes via the homolysis of sulfinyl oximes from ketoximes and sulfinyl chloride. This method features catalyst-free, step-efficient functionalization and prominent functional group tolerance, providing a straightforward, green, and widely applicable approach to accessing ß-amino sulfone derivatives.

2.
Adv Mater ; : e2405163, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816034

RESUMO

Large language models (LLMs) have attracted widespread attention recently, however, their application in specialized scientific fields still requires deep adaptation. Here, an artificial intelligence (AI) agent for organic field-effect transistors (OFETs) is designed by integrating the generative pre-trained transformer 4 (GPT-4) model with well-trained machine learning (ML) algorithms. It can efficiently extract the experimental parameters of OFETs from scientific literature and reshape them into a structured database, achieving precision and recall rates both exceeding 92%. Combined with well-trained ML models, this AI agent can further provide targeted guidance and suggestions for device design. With prompt engineering and human-in-loop strategies, the agent extracts sufficient information of 709 OFETs from 277 research articles across different publishers and gathers them into a standardized database containing more than 10 000 device parameters. Using this database, a ML model based on Extreme Gradient Boosting is trained for device performance judgment. Combined with the interpretation of the high-precision model, the agent has provided a feasible optimization scheme that has tripled the charge transport properties of 2,6-diphenyldithieno[3,2-b:2',3'-d]thiophene OFETs. This work is an effective practice of LLMs in the field of organic optoelectronic devices and expands the research paradigm of organic optoelectronic materials and devices.

3.
Chem Commun (Camb) ; 60(34): 4577-4580, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38573313

RESUMO

The application of strain induces a transition in the ground-state magnetic configuration of Janus TiVC MXene from A-AFM to FM. A new system and method of solid-state disk information storage without electricity is developed based on the as-discovered reversible magnetic state transition in TiVC, which can achieve efficient storage of information in extremely harsh conditions.

4.
Heliyon ; 9(10): e20609, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37916095

RESUMO

Auroras are bright occurrences when high-energy particles from the magnetosphere and solar wind enter Earth's atmosphere through the magnetic field and collide with atoms in the upper atmosphere. The morphological and temporal characteristics of auroras are essential for studying large-scale magnetospheric processes. While auroras are visible to the naked eye from the ground, scientists use deep learning algorithms to analyze all-sky images to understand this phenomenon better. However, the current algorithms face challenges due to inefficient utilization of global features and neglect the excellent fusion of local and global feature representations extracted from aurora images. Hence, this paper introduces a Hash-Transformer model based on Vision Transformer for aurora retrieval from all-sky images. Experimental results based on real-world data demonstrate that the proposed method effectively improves aurora image retrieval performance. It provides a new avenue to study aurora phenomena and facilitates the development of related fields.

5.
J Eat Disord ; 11(1): 153, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37697411

RESUMO

Body talk has received increasing research attention in recent years, with accumulating evidence supporting the link between body talk and eating and body image disturbances. However, research on body talk in China is still relatively scarce and generally focused on fat talk, especially in women, and much remains unknown about muscle talk and positive body talk for both Chinese women and men. To promote a better understanding of body talk in the Chinese context, the present study adapted the Body Talk Scale (BTS) into Chinese Mandarin (i.e., C-BTS) and evaluated the factor structure and psychometric properties of the C-BTS in Chinese adult women and men. The English version of the BTS was translated into Chinese Mandarin with standard procedures. With 300 Chinese women (Mage = 29.48 years, SD = 7.26) and 300 men (Mage = 29.36 years, SD = 6.81), we examined the factor structure and gender invariance of the C-BTS, as well as internal consistency reliability, test-retest reliability, and construct validity, including convergent, concurrent, and incremental validity of the C-BTS. The results indicated that, consistent with the development study of the BTS, the C-BTS had three subscales (i.e., Negative Fat Talk, Negative Muscle Talk, and Positive Body Talk) and good reliability and validity. The findings demonstrate that the C-BTS can be a useful measure of body talk in both Chinese women and men.


The Body Talk Scale (BTS) measures three types of body talk, including negative fat talk, negative muscle talk, and positive body talk. The present study adapted the English version of the BTS into Chinese Mandarin and examined its psychometric properties in Chinese adult women and men. Results showed that the BTS had adequate reliability and validity in Chinese adults and could be used to assess body talk in Chinese women and men.

6.
J Am Chem Soc ; 145(30): 16711-16717, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37486147

RESUMO

Intelligent molecular machines that are driven by light, electricity, and temperature have attracted considerable interest in the fields of chemistry, materials, and biology. Herein, a unimolecular chiral stepping inversion molecular machine (SIMM) was constructed by a coupling reaction between dibromo pillar[5]arene and a tetrathiafulvalene (TTF) derivative (PT3 and PT5). Compared with the longer aliphatic linker PT5, PT3 with a shorter aliphatic linker shows chiral stepping inversion, achieving chiral inversion under a two-electron redox potential. Benefiting from the successive reversible two-electron redox potential of TTF, the self-exclusion and self-inclusion conformational transformations of SIMM can proceed in two steps under redox, leading to the chirality step inversion in the pillar[5]arene core. Electrochemical experiments and circular dichroism (CD) spectra show that the redox processes can cause SIMM CD signaling to reversibly switch. More importantly, as the oxidant Fe(ClO4)3 was increased from 0.1 to 1 equiv, the CD spectral signal of SIMM disappeared at 1 equiv, and further addition of Fe(ClO4)3 resulted in the CD signal reversed from positive to negative at 309 nm, indicating that the chirality was reversed after chemical oxidation and reached a negative maximum with the addition of 2 equiv Fe(ClO4)3; thus, redox-triggered chiral stepping inversion was achieved. Furthermore, the chiral inversion can be restored to its original state after the addition of 2 equiv of reducing agent, sodium ascorbate. This work demonstrates unimolecular chiral stepping inversion, providing a new perspective on stimulus-responsive chirality in molecular machines.

7.
Int J Eat Disord ; 56(10): 1875-1886, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37386889

RESUMO

OBJECTIVE: We tested an integrated model of three prominent theories of disordered eating (tripartite influence theory, objectification theory, and social comparison theory) in a sample of older Chinese men and women. METHOD: Chinese older men (n = 270) and women (n = 160) completed questionnaires assessing the tripartite influence, objectification, and social comparison theories and thinness- and muscularity-oriented disordered eating. Two structural equation models were tested in Chinese older men and women. RESULTS: The integrated model showed good model fit and described meaningful variance in thinness- and muscularity-oriented disordered eating in Chinese older men and women. Higher appearance pressures were uniquely related to higher muscularity-oriented disordered eating in men. Across both gender groups, higher thinness internalization was uniquely related to higher thinness- and muscularity-oriented disordered eating, and in women only, higher muscularity internalization was uniquely related to lower thinness-oriented disordered eating. In men, higher upward and downward body image comparisons were uniquely related to higher and lower, respectively, muscularity-oriented disordered eating. In women, higher upward body image comparisons were only uniquely related to higher muscularity-oriented disordered eating while higher downward body image comparisons were uniquely related to both outcomes. Higher body shame was uniquely related to higher thinness-oriented disordered eating across both groups and in men alone, higher body shame was also uniquely related to higher muscularity-oriented disordered eating. DISCUSSION: Findings, which tested the integration of tripartite influence, objectification, and social comparison theories, inform the prevention and treatment of disordered eating in Chinese older populations. PUBLIC SIGNIFICANCE: The present study is the first to describe theories of disordered eating (tripartite influence, objectification, and social comparison) in Chinese older adults. Findings suggested good model fit and the integrated models described meaningful variance in thinness- and muscularity-oriented disordered eating in Chinese older women and men. Findings extend existing theories of disordered eating and, pending further study, may inform theory-driven prevention and treatment approaches in Chinese older adults.

8.
Org Biomol Chem ; 20(38): 7593-7598, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-36128897

RESUMO

ß-Amino carbonyl substructures are privileged motifs in natural products and active pharmaceutical compounds. Here, we report a photoinduced metal-free and highly regioselective intermolecular carboimination method via the simultaneous introduction of amino and carbonyl groups into the CC double bond in one step, providing straightforward, green and general access to both ß-amino acid and ß-amino ketone motifs from readily available alkene feedstocks. The mild reaction conditions, excellent functional group tolerance and product diversity should make this a broadly applicable carboimination approach of very broad interest to organic and medicinal chemists.


Assuntos
Alcenos , Produtos Biológicos , Alcenos/química , Aminoácidos/química , Cetonas/química , Metais , Preparações Farmacêuticas
9.
Body Image ; 40: 110-115, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34915302

RESUMO

A number of previous studies reported a link between body mass index (BMI) and body appreciation; however, many of these studies were conducted in Western countries and addressed younger samples. Older adults, especially in East Asia, remain insufficiently examined. Therefore, the objective of this study was to examine the relationship between BMI and body appreciation and to explore two potential mediators, body dissatisfaction and body image inflexibility, as proposed in a previous meta-analysis. A community-based cross-sectional study was performed among 313 older Chinese men and women (M = 67.90, SD = 7.94). Mediation tests were conducted to examine the roles of body dissatisfaction and body image inflexibility in the relationship between BMI and body appreciation. BMI correlated significantly with body appreciation, body dissatisfaction, and body image inflexibility among older women but did not correlate with body appreciation among older men. Body dissatisfaction and body image inflexibility emerged as significant mediators in the relationship between BMI and body appreciation among older Chinese women. Reducing body dissatisfaction and body image inflexibility may be potential targets for helping older women with high BMI to promote their body appreciation.


Assuntos
Insatisfação Corporal , Imagem Corporal , Idoso , Imagem Corporal/psicologia , Índice de Massa Corporal , China , Estudos Transversais , Feminino , Humanos , Masculino , Satisfação Pessoal
10.
Nutrients ; 13(4)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923539

RESUMO

Sleep quality, diet quality, and physical activity are significant factors influencing physical and mental health. However, few studies have explored their underlying mechanisms, especially among the elderly population in East Asia, where people have food culture and lifestyles distinct from those living in Western countries. Therefore, the current study aimed to explore the relationships among sleep quality, diet quality, physical activity, and physical and mental health in a Chinese elderly sample. Sleep quality, diet quality, physical activity, physical health, and mental health were investigated among 313 Chinese elderly (aged 51-92 years, M = 67.90, SD = 7.94). Mediation analysis was used to examine the empirical model based on previous theories and literature. Close positive relationships were observed between all factors investigated (r = 0.22~0.73, p < 0.001). The relationships between sleep quality and physical and mental health were partially mediated by diet quality and physical activity. In clinical interventions, sleep quality, diet quality, and physical activity can be targeted to improve physical and mental health among the older adult populations.


Assuntos
Dieta Saudável/psicologia , Exercício Físico , Comportamento Alimentar , Saúde Mental , Sono , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/psicologia , China , Inquéritos sobre Dietas , Dieta Saudável/etnologia , Comportamento Alimentar/etnologia , Feminino , Avaliação Geriátrica , Nível de Saúde , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Inquéritos e Questionários
11.
Int J Eat Disord ; 54(2): 212-221, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33135212

RESUMO

OBJECTIVE: Obsessive attention to healthy eating might paradoxically lead to physical and psychosocial impairments, a potential eating disorder termed orthorexia nervosa (ON). An ongoing debate concerns whether ON should be categorized as an eating disorder, an obsessive-compulsive disorder, or a mental disorder at all. A missing voice in this debate is ON in the elderly, which remains unknown, despite health being a more central issue in everyday life during old age. Similarly missing is ON in East Asia, which remains largely unexplored. METHOD: The current study investigated ON in 313 Chinese elderly (M = 67.90, SD = 7.94) using the Chinese version of the Düsseldorf Orthorexia Scale (C-DOS). Questionnaires were used to measure traditional eating disorder symptomatology, body image (body dissatisfaction, body appreciation, and functionality appreciation), lifestyle behaviors (fruit and vegetable consumption and time spent on physical activity), and indexes of well-being (psychological distress, food-related quality of life, and life satisfaction). RESULTS: ON symptoms were positively related to physical activity, fruit and vegetable (F&V) consumption, body appreciation, functionality appreciation, and life satisfaction, but negatively related to body dissatisfaction. Compared with those without ON, the elderly with ON scored higher on positive psychological/lifestyle measures but lower on negative psychological measures. DISCUSSION: Contrary to the dominant characterization of ON as a variant of disordered eating, in Chinese elderly ON was associated with several positive lifestyle and psychological measures. Thus, ON in the elderly might not be viewed as a form of disordered eating but can be protective and beneficial.


Assuntos
Imagem Corporal , Transtornos da Alimentação e da Ingestão de Alimentos , Satisfação Pessoal , Idoso , Imagem Corporal/psicologia , China , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Humanos , Psicologia Positiva , Inquéritos e Questionários
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