Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
2.
Front Psychol ; 14: 1275367, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38425347

RESUMO

Introduction: Using students in the Liangshan Yi autonomous prefectures of southwestern China (n = 585; 13-15 years old), we examined (i) the effects of students' perception of their teachers' ethnic-racial socialization on their ethnic identity and mental health outcomes of depressive and stress symptoms; (ii) the effects of students' ethnic identity on their depressive and stress symptoms; (iii) the differential associations among these factors in Yi ethnic minority versus Han cultural majority students. Methods: We conducted a cross-sectional survey and used multistage sampling to collect the information. Chinese-validated standardized measures were used: the Patient Health Questionaires-9, Children's Revised Impact of Event Scale-8, Multigroup Ethnic Identity Measure, Cultural Socialization Scale, and Teachers' Attitude on Adoption of Cultural Diversity Scale. Multigroup confirmatory factor analysis and multigroup structural equation modeling were employed. Results: Comparing the findings in Yi and Han students, their perception of teachers' ethnic-racial socialization had dissimilar effects on their ethnic identity and mental health outcomes. Three key findings comparing the differences between Yi and Han students were as follows: (i) students' perception of their teachers' multicultural socialization practices positively affected the ethnic identity of both Yi and Han young people; however, their perception of their teachers' socializing them to their own cultures did not exert any effect; (ii) students' perception of teachers' multicultural socialization practices had different mental health effects on Yi versus Han students; and (iii) ethnic identity affected the mental health of Yi ethnic minority students only. Conclusion: The findings underscore the importance of teachers' multicultural socialization in the ethnic identity development of both Yi ethnic minority and Han majority students. Ethnic identity serves as a linking variable bridging perceived teachers' multicultural socialization practices and mental health in Yi ethnic minority students but not among the Han cultural majority youths. Research, practice, and policy implications relevant to the global context are also discussed.

3.
J Am Chem Soc ; 144(47): 21783-21790, 2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36395367

RESUMO

While heteroatom-centered radicals are understood to be highly electrophilic, their ability to serve as transient electron-withdrawing groups and facilitate polar reactions at distal sites has not been extensively developed. Here, we report a new strategy for the electronic activation of halophenols, wherein generation of a phenoxyl radical via formal homolysis of the aryl O-H bond enables direct nucleophilic aromatic substitution of the halide with carboxylate nucleophiles under mild conditions. Pulse radiolysis and transient absorption studies reveal that the neutral oxygen radical (O•) is indeed an extraordinarily strong electron-withdrawing group [σp-(O•) = 2.79 vs σp-(NO2) = 1.27]. Additional mechanistic and computational studies indicate that the key phenoxyl intermediate serves as an open-shell electron-withdrawing group in these reactions, lowering the barrier for nucleophilic substitution by more than 20 kcal/mol relative to the closed-shell phenol form of the substrate. By using radicals as transient activating groups, this homolysis-enabled electronic activation strategy provides a powerful platform to expand the scope of nucleophile-electrophile couplings and enable previously challenging transformations.


Assuntos
Eletrônica , Elétrons , Ácidos Carboxílicos , Fenol , Espécies Reativas de Oxigênio
4.
Chem Rev ; 122(2): 2017-2291, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-34813277

RESUMO

We present here a review of the photochemical and electrochemical applications of multi-site proton-coupled electron transfer (MS-PCET) in organic synthesis. MS-PCETs are redox mechanisms in which both an electron and a proton are exchanged together, often in a concerted elementary step. As such, MS-PCET can function as a non-classical mechanism for homolytic bond activation, providing opportunities to generate synthetically useful free radical intermediates directly from a wide variety of common organic functional groups. We present an introduction to MS-PCET and a practitioner's guide to reaction design, with an emphasis on the unique energetic and selectivity features that are characteristic of this reaction class. We then present chapters on oxidative N-H, O-H, S-H, and C-H bond homolysis methods, for the generation of the corresponding neutral radical species. Then, chapters for reductive PCET activations involving carbonyl, imine, other X═Y π-systems, and heteroarenes, where neutral ketyl, α-amino, and heteroarene-derived radicals can be generated. Finally, we present chapters on the applications of MS-PCET in asymmetric catalysis and in materials and device applications. Within each chapter, we subdivide by the functional group undergoing homolysis, and thereafter by the type of transformation being promoted. Methods published prior to the end of December 2020 are presented.


Assuntos
Elétrons , Prótons , Técnicas de Química Sintética , Transporte de Elétrons , Oxirredução
5.
J Health Psychol ; 26(4): 525-542, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-30618294

RESUMO

This study explored how Chinese women with donor-assisted conception experienced loss of genetic continuity and managed donor-assisted conception-related information. Through Interpretative Phenomenological Analysis, a thematic framework on women's beliefs, motivation, and behaviors in information management was constructed. Contrary to the Western trend toward disclosure, it was found that Chinese women strongly preferred to conceal, in order to protect their family members, the parent-child relationship, and family stability. Participants' strong preference was also indicated in specific behaviors that ensure information concealment. The findings of this study may contribute toward the development of culturally sensitive clinical guidelines for counseling practice that supports infertile couples' decision-making.


Assuntos
Infertilidade , Relações Pais-Filho , Criança , China , Revelação , Feminino , Humanos , Motivação
6.
Angew Chem Int Ed Engl ; 59(29): 11845-11849, 2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-32227658

RESUMO

We report a catalytic, light-driven method for the intramolecular hydroetherification of unactivated alkenols to furnish cyclic ether products. These reactions occur under visible-light irradiation in the presence of an IrIII -based photoredox catalyst, a Brønsted base catalyst, and a hydrogen-atom transfer (HAT) co-catalyst. Reactive alkoxy radicals are proposed as key intermediates, generated by direct homolytic activation of alcohol O-H bonds through a proton-coupled electron-transfer mechanism. This method exhibits a broad substrate scope and high functional-group tolerance, and it accommodates a diverse range of alkene substitution patterns. Results demonstrating the extension of this catalytic system to carboetherification reactions are also presented.


Assuntos
Alcenos/química , Éteres/química , Catálise , Transporte de Elétrons , Irídio , Modelos Moleculares , Estrutura Molecular , Prótons
7.
Chem Sci ; 11(41): 11124-11141, 2020 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-33384861

RESUMO

Alkoxy radicals have long been recognized as powerful synthetic intermediates with well-established reactivity patterns. Due to the high bond dissociation free energy of aliphatic alcohol O-H bonds, these radicals are difficult to access through direct homolysis, and conventional methods have instead relied on activation of O-functionalized precursors. Over the past decade, however, numerous catalytic methods for the direct generation of alkoxy radicals from simple alcohol starting materials have emerged and created opportunities for the development of new transformations. This minireview discusses recent advances in catalytic alkoxy radical generation, with particular emphasis on progress toward the direct activation of unfunctionalized alcohols enabled by transition metal and photoredox catalysis.

8.
Int J Behav Med ; 16(2): 91-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19291413

RESUMO

BACKGROUND: Daily spiritual experience (DSE) refers to one's interaction with the transcendent in day-to-day life. Underwood's Daily Spiritual Experience Scale mic(DSES) was developed to measure this experiential component of religiousness and spirituality. Addressing ordinary daily experiences rather than particular beliefs, DSES has transcultural applicability potential. PURPOSE: The current study aimed to develop and evaluate the Chinese version of DSES (DSES-C). METHOD: The 16-item scale was translated faithfully through standard translation/back-translation procedures. The term "God" required an extended definition embracing both a humanized and a philosophical higher power in Chinese culture. The translated scale plus a battery of validation scales were administered to staff of a large rehabilitation service complex, resulting in 245 completed questionnaires. RESULTS: Exploratory factor analysis revealed a similar factor structure as the original English version and similar problems with items 13 (compassion) and 14 (mercy). After carefully deliberating on the Chinese conceptualization of spirituality and balancing psychometric properties, the one-factor 16-item structure of the English version was supported. DSES-C showed high internal consistency (Cronbach's alpha = 0.97). Construct validity was supported by correlations with validation scales in expected directions. CONCLUSION: The psychometric properties of DSES were similar to the English version in factor structure, internal consistency, and convergence/divergence construct validity.


Assuntos
Autoavaliação (Psicologia) , Espiritualidade , Inquéritos e Questionários/normas , Adulto , Cultura , Análise Fatorial , Feminino , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Autoimagem , Tradução , Adulto Jovem
9.
Patient Educ Couns ; 66(3): 278-95, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17300913

RESUMO

OBJECTIVE: To assess the reliability and validity of a simplified questionnaire-based measure of informed choice in populations with low literacy. The measure comprises (a) knowledge about the test and (b) attitudes towards undergoing the test. Responses to (a) and (b) together with information on test uptake, are used to classify choices as informed or uninformed. METHODS: A cross-sectional study of 79 pregnant women (46 women with higher, and 33 with lower education levels) completed a simplified questionnaire, a standardised questionnaire and a semi-structured interview about antenatal sickle cell and thalassaemia (SCT) screening. The measures used were: (a) informed choice, based on knowledge about the test, attitudes towards undergoing the test, and uptake of the test and (b) ease of completion measures. RESULTS: The simplified measures of knowledge and attitudes were able to distinguish between women classified according to interview responses as having good or poor knowledge (knowledge scores 6.8 versus 3.2, p<0.001), and positive or negative attitudes towards undergoing the test (attitude scores 20.6 versus 16.2, p=0.023). There was no difference in rates of informed choice derived from the simplified or standardised measures (54% versus 51%, 95% CI difference -11 to 19). Women with lower levels of education found the simplified questionnaire easier to complete than the standardised version (11.0 versus 9.6, p=0.009). Those with higher levels of education found no difference in ease of completion between the two versions of the questionnaire (11.8 versus 11.6, p=0.54). CONCLUSION: A simplified questionnaire-based measure of informed choice in antenatal SCT screening is as reliable and valid as a more complex standardised version and for those with less education, easier to complete. PRACTICE IMPLICATIONS: The simplified questionnaire-based measure of informed choice is suitable for use in populations with low and high levels of education.


Assuntos
Atitude Frente a Saúde , Escolaridade , Conhecimentos, Atitudes e Prática em Saúde , Consentimento Livre e Esclarecido , Gestantes/psicologia , Inquéritos e Questionários/normas , Adulto , Instituições de Assistência Ambulatorial , Anemia Falciforme/diagnóstico , Anemia Falciforme/genética , Comportamento de Escolha , Compreensão , Estudos Transversais , Etnicidade/educação , Etnicidade/psicologia , Feminino , Testes Genéticos/psicologia , Humanos , Consentimento Livre e Esclarecido/psicologia , Londres , Negativismo , Educação de Pacientes como Assunto/normas , Gravidez , Cuidado Pré-Natal , Diagnóstico Pré-Natal/psicologia , Talassemia/diagnóstico , Talassemia/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...