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1.
Org Biomol Chem ; 19(45): 9855-9859, 2021 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-34761765

RESUMEN

A photochemical thiol addition/aerobic oxidation cascade reaction has been developed. This protocol enables efficient oxidative coupling of epoxides and thiols to access structurally valuable ß-hydroxylsulfoxides. A broad range of functional groups are compatible to obtain moderate to good yields of the target products. Mechanistic studies revealed a sequential reaction pathway involving base-promoted thiol addition of thiols to epoxides and visible-light-induced aerobic oxygenation of thioethers.

2.
Small ; 15(36): e1902118, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31328882

RESUMEN

As a solid precursor to O2 and hydrogen peroxide (H2 O2 ), calcium peroxide (CaO2 ) has found widespread use in applications related to disinfection and contaminant degradation. The lack of uniform nanoparticles, however, greatly limits the potential use of this material in other applications related to medicine. Here, a new route to the facile synthesis of CaO2 nanocrystals and their spherical aggregates with uniform, controllable sizes is reported. The synthesis involves the reaction between CaCl2 and H2 O2 to generate CaO2 primary nanocrystals of 2-15 nm in size in ethanol, followed by their aggregation into uniform, spherical particles with the aid of poly(vinyl pyrrolidone) (PVP). The average diameter of the spherical aggregates can be easily tuned in the range of 15-100 nm by varying the concentrations of CaCl2 and/or PVP. For the spherical aggregates with a smaller size, they release H2 O2 and O2 more quickly when exposed to water, resulting in superior antimicrobial activity. This study not only demonstrates a new route to the synthesis of uniform CaO2 nanocrystals and their spherical aggregates but also offers a promising bacteriostatic agent with biodegradability.


Asunto(s)
Nanopartículas del Metal/química , Nanopartículas/química , Peróxidos/química , Antibacterianos/química , Cloruro de Calcio/química , Hidrógeno/química , Peróxido de Hidrógeno/química , Oxígeno/química , Polivinilos/química , Pirrolidinas/química
3.
Int J Psychol ; 53(4): 278-286, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27503139

RESUMEN

The process of globalisation has increased the opportunity for Chinese individuals to utilise influences from other cultures that differ from their own collectivistic culture. The explorations of the impact of acculturation on Chinese individuals' self-construals have become intriguing. Thus, we recruited German-Chinese (N = 192) people who live in Germany and had direct bicultural experiences, as well as Mainland-Chinese (N = 192) people who live in Mainland China and had internalised a second culture through more indirect means of exposure. We investigated their accessibility to both interdependent and independent cultural frameworks using temporal self-construal priming. The results showed that priming effects were observed in both cultural groups. However, the self-construals of the German-Chinese participants were more flexible than those of Mainland-Chinese under self-construal priming. Also, the results suggested that women were easier to be influenced by direct bicultural experiences, due to their private and collective self were different between the two cultures. These findings provide evidence regarding the opinion that individuals could use influences from more than one culture. More importantly, these results suggest that the acculturation induced by direct bicultural experiences facilitates cultural frame switching.


Asunto(s)
Aculturación , Autoimagen , Adolescente , Adulto , Pueblo Asiatico , Femenino , Humanos , Masculino
4.
Psychol Rep ; 116(1): 292-310, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25621668

RESUMEN

This study investigated the development of cultural variability in interdependent self-construal by comparing the differences in the tripartite self-concept of adolescent samples from the Han and Uyghur cultures. Participants (460 males, 522 females; M age = 16.3 yr., SD = 4.8) in the sub-phases of pre-, early-, mid-, late- and post-adolescence were asked to completed the revised Twenty Statements Test, and the items generated by the participants were coded into private, relational, and collective self-statements. The private self-statements were further differentiated by personal and social orientation, and the relational self-statements were further coded into family and friend focus. The relational aspect of an individual's self, or personal relationship, became increasingly important with age in the Han cultural groups, whereas the collective aspect of an individual's self, or social identity, became increasingly important with age in the Uyghur cultural groups. These findings seem to show the development of differences between relational and collective interdependent self-construals. Furthermore, these findings emphasize the need for further research into the development of within-cultural differences in self-construal.


Asunto(s)
Desarrollo del Adolescente , Comparación Transcultural , Relaciones Interpersonales , Autoimagen , Identificación Social , Adolescente , Adulto , Niño , China/etnología , Femenino , Humanos , Masculino , Adulto Joven
5.
Psychol Rep ; 115(1): 179-98, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25153957

RESUMEN

Differences in the concepts of private, collective, and relational selves between two Chinese ethnic groups, the Han and Tibetan-adhering to the philosophies of Confucianism and Tibetan Buddhism, respectively-were examined. 128 students (54 men, 74 women; M age = 20.9 yr., SD = 2.2) completed the revised Twenty Statements Test and self-reference paradigm. Study 1 found that for Han participants relational and private selves were ranked similarly and as more important than the collective self. Studies 2 and 3 found that adjective words describing private and relational selves were recalled in greater proportions than words describing the collective self. Tibetan participants showed no significant differences between the three self-cognitions. The findings correspond to differences in self-identity among these two subcultures.


Asunto(s)
Comparación Transcultural , Religión y Psicología , Autoimagen , Adulto , China/etnología , Femenino , Humanos , Masculino , Tibet/etnología , Adulto Joven
6.
Colloids Surf B Biointerfaces ; 204: 111803, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33964529

RESUMEN

The hypoxic tumor environment prevents the generation of reactive oxygen species (ROS), reducing the therapeutic efficiency. We construct oleylamine (OA) coated CaO2/Fe3O4 nanocomposites to realize oxygen-independent generation of ROS and high efficient treatment of cancer. In the tumor site, CaO2 reacts with water to generate H2O2, which can be catalized by Fe2+ that is produced by Fe3O4, to form highly toxic hydroxyl radicals (∙OH). To inhibit the premature reaction, CaO2/Fe3O4 nanoparticles were coated with pH sensitive OA. The nanocomposites exhibited remarkable tumor growth inhibition ability and favorable biocompatibility, holding a great potential for hypoxic tumor therapy.


Asunto(s)
Nanocompuestos , Neoplasias , Peróxido de Hidrógeno , Radical Hidroxilo , Neoplasias/tratamiento farmacológico , Oxígeno , Especies Reactivas de Oxígeno
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