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1.
Multimed Tools Appl ; : 1-17, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-37362683

RESUMO

Identifying and analyzing the public's opinion of focal events during a major epidemic can help the government grasp the vicissitudes of network public opinion in a timely manner and provide the appropriate responses. Taking the COVID-19 epidemic as an example, this study begins by using Python-selenium to capture the original text and comment data related to COVID-19 from Sina Microblog's CCTV News from Jan. 19, 2020, to Feb. 20, 2020. The study subsequently uses a manual interpretation method to classify the Weibo content and analyzes the shifting focus phenomena of network public opinion based on the moving average method. Next, the study uses an enhances TF-IDF to extract keywords from the Weibo comment and uses the keywords to construct a word co-occurrence network. The results show that during the epidemic, the network public opinion focus shifted significantly over time. With the progression of the epidemic, the focus of network public opinion diversified, and various categories stabilized. Compared to simple keyword and text classification recognition focus problems, the proposed model, which is highly accurate, identified multiple network public opinion focus problems and described the core contradictions of the different focus problems.

2.
Cyberpsychol Behav Soc Netw ; 26(3): 188-197, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36787470

RESUMO

Consumption is undergoing a digital revolution brought about by virtual technology, and the emergence of virtual spokespersons has changed the pattern of advertising endorsement sales. Are virtual character spokespersons better than real celebrity spokespersons? This article aims to explore the relationships between different types of advertising spokespersons, different types of advertising scenarios, and consumers' purchase intentions. The results of 2 pilot experiments and 4 formal experiments show that compared with spokespersons by real people, virtual character spokespersons have a greater positive impact on consumers' purchase intentions, which is achieved through the mediating role of psychological need satisfaction. In addition, different advertising scenarios provided by virtual technology have a moderating effect on this process. This empirical study investigates the possible positive effects of virtual character spokesperson compared with real character spokesperson and expands the results of spokesperson category based on self-determination theory.


Assuntos
Publicidade , Comportamento do Consumidor , Humanos , Inquéritos e Questionários , Intenção , Comércio
3.
Front Psychol ; 12: 555150, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025490

RESUMO

The purpose of this study is to explore the influence of consumers' choice deferral behavior on their intertemporal choice preference. The empirical study shows that consumers' choice deferral behavior can significantly affect their intertemporal decision preference through the level of hopefulness. Compared with non-choice deferral behavior, choice deferral behavior can improve the level of consumers' sense of hopefulness, which then makes them prefer larger-longer interests in intertemporal decision-making. The effect of consumers' sense of hopefulness on their intertemporal choice preference is moderated by their perceived information integrity. When the perceived information integrity is low, the effect of hopefulness on intertemporal decision preference will be enhanced, but when the perceived information integrity is high, the effect of hopefulness on intertemporal decision preference will not be affected. In addition, the theoretical and practical significance of this study and the prospect of future research are also discussed.

4.
Sensors (Basel) ; 19(5)2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30836692

RESUMO

The monotonic work function of graphene makes it difficult to meet the electrode requirements of every device with different band structures. Two-dimensional (2D) transition metal carbides (TMCs), such as carbides in MXene, are considered good candidates for electrodes as a complement to graphene. Carbides in MXene have been used to make electrodes for use in devices such as lithium batteries. However, the small lateral size and thermal instability of carbides in MXene, synthesized by the chemically etching method, limit its application in optoelectronic devices. The chemical vapor deposition (CVD) method provides a new way to obtain high-quality ultrathin TMCs without functional groups. However, the TMCs film prepared by the CVD method tends to grow vertically during the growth process, which is disadvantageous for its application in the transparent electrode. Herein, we prepared an ultrathin Mo2C-graphene (Mo2C-Gr) hybrid film by CVD to solve the above problem. The work function of Mo2C-Gr is between that of graphene and a pure Mo2C film. The Mo2C-Gr hybrid film was selected as a transparent hole-transporting layer to fabricate novel Mo2C-Gr/Sb2S0.42Se2.58/TiO2 two-sided photodetectors. The Mo2C-Gr/Sb2S0.42Se2.58/TiO2/fluorine-doped tin oxide (FTO) device could detect light from both the FTO side and the Mo2C-Gr side. The device could realize a short response time (0.084 ms) and recovery time (0.100 ms). This work is believed to provide a powerful method for preparing Mo2C-graphene hybrid films and reveals its potential applications in optoelectronic devices.

5.
Am J Chin Med ; 46(8): 1743-1770, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30518235

RESUMO

Diabetes mellitus (DM) is a serious metabolic disorder which has reached epidemic proportions all over the world. Despite tremendous developments in medicinal chemistry, traditional medicine is still commonly used for the prevention and treatment of DM. Traditional herbal medicines have played a major role in the management of DM in Asian countries. In particular, mulberry has commonly been utilized in China for the treatment of DM for thousands of years. In the last decade, numerous preclinical findings have suggested that mulberry is a promising therapeutic agent for the treatment of DM, and the polyhydroxylated alkaloids, flavonoids and polysaccharides from mulberry may be the potential active components. The present review systematically summarizes the chemical composition of mulberry and the pharmacological effects of different medicinal parts on DM; these effects include influences on glucose absorption, insulin (INS) production/secretion, anti-oxidation and anti-inflammation processes. After summarizing our research findings, we will discuss the challenges and opportunities and explore the direction of future research and the potential for developing mulberry into pharmaceuticals for the widespread treatment of DM.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Hipoglicemiantes , Morus/química , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Alcaloides/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Animais , Anti-Inflamatórios , Antioxidantes , Diabetes Mellitus/prevenção & controle , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Glucose/metabolismo , Humanos , Hidroxilação , Secreção de Insulina/efeitos dos fármacos , Medicina Tradicional Chinesa , Morus/anatomia & histologia , Extratos Vegetais/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia
6.
Sci Rep ; 4: 7050, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25394410

RESUMO

Hybrid carbon films composed of graphene film and porous carbon film may give full play to the advantages of both carbon materials, and have great potential for application in energy storage and conversion devices. Unfortunately, there are very few reports on fabrication of hybrid carbon films. Here we demonstrate a simple approach to fabricate free-standing sandwich-structured hybrid carbon film composed of porous amorphous carbon film and multilayer graphene film by chemical vapor deposition in a controllable and scalable way. Hybrid carbon films reveal good electrical conductivity, excellent flexibility, and good compatibility with substrate. Supercapacitors assembled by hybrid carbon films exhibit ultrahigh rate capability, wide frequency range, good capacitance performance, and high-power density. Moreover, this approach may provide a general path for fabrication of hybrid carbon materials with different structures by using different metals with high carbon solubility, and greatly expands the application scope of carbon materials.

7.
Zhongguo Zhong Yao Za Zhi ; 38(8): 1193-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23944034

RESUMO

To explore the alternative material for the stems of Evodia lepta used in clinic, the leaves extract of E. lepta was chemically investigated by silica gel, Sephadex LH-20, ODS column chromatographies, and preparative HPLC and the structures of the compounds were identified mainly by spectroscopic methods. Ten known compounds 4-hydroxy-4, 7-dimethyl-1-tetralone (1), (6R, 7E) -4, 7-megastigmadien-3, 9-dione (2), 4-megastigmen-3, 9-dione (3), formononetin (4), daidzein (5), oroxylin A (6), wogonin (7), 5, 7-dihydroxy-3, 4'-dimethoxyflavone (8), N-trans-coumaroyltyranine (9) and (E) -p-hydroxycinnamic acid (10), have been obtained and identified. All these compounds were isolated from this species for the first time. The results revealed that there is a considerate chemical difference between the stems and leaves of E. lepta.


Assuntos
Evodia/química , Folhas de Planta/química , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
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