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1.
Health Commun ; : 1-16, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38655579

RESUMEN

The role of experts in news coverage has become increasingly prominent, but the evidence regarding the effectiveness of expert opinions in affecting public behavior remains mixed. This study seeks to examine the influence of expert opinions covered in the news on the public's response to public health crises. By adopting a macro-level framing perspective, we investigated how framing consistency, a macro-level concept indicating the agreement between expert opinions in news coverage and government policies or among peer experts, evolves over time and its temporal causal relationship with public behavior. Specifically, this study collected all press news coverage in Hong Kong over four months during the fifth outbreak, including 1,416 articles with 650 expert opinions, as well as the vaccination data that paralleled with this period. We constructed time series of expert opinions and vaccination behavior, and then conducted Vector Autoregressive (VAR) models with Granger causality analysis to examine how framing consistency of expert opinions in news coverage influenced vaccination. The results indicate that the consistent framing between expert opinions and government policies increased COVID-19 vaccination during the fifth outbreak in Hong Kong, while conflicting opinions responding to government policies had no significant effect on vaccination. Opinions among medical experts on COVID-19 issues also did not significantly impact vaccination. The implications for designing communication strategies and enhancing public behavioral support during public health crises are discussed.

2.
Chem Asian J ; 18(6): e202201285, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36704999

RESUMEN

The peroxymonosulfate (PMS) activation mechanism is closely related to the structure/configuration of the "active site" of the Fenton-like catalysts. In this paper, it is shown that Cu2+ chemically bonds the surface of birnessite at the Mn vacancy site to form triple-corner-sharing inner-sphere surface complexes (Cu-Bir), which regulates the PMS activation mechanism. Birnessite/PMS Fenton-like system degrades phenol via a non-radical mechanism, which involves high valent Mn(V)=O generated from the surface reaction of Mn(III) with adsorbed PMS. While Cu-Bir initiates an additional radical mechanism that involves reactive oxygen species of ⋅O2 - and 1 O2 , and the k value of 5Cu-Bir is 1.9 times higher than that of Bir. The Fenton-like reaction mechanism of the Cu-Bir/PMS system is thus proposed as a radical and non-radical cooccurrence mechanism, which involves a synergistic effect that the radical pathway accelerates the regeneration of Mn(III) for the non-radical pathway, and the non-radical pathway assists to produce 1 O2 for the radical pathway.

3.
Chem Asian J ; 18(2): e202201134, 2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-36459407

RESUMEN

Oxoiron(IV) species are a critical intermediate in the Fe-based Fenton-like process at circumneutral pH, and its oxidative reactivity is closely related to the ligands. An optional inorganic host material, MoS2 , is selected to construct a highly reactive sulfur ligand coordinated Fe species in this work. The Fe species doped in MoS2 is presented as the FeII centre and triggers the transformation of the 2H phase to the octahedral 1T phase MoS2 . The role of the interaction between doped Fe and the MoS2 host lattice on the formation of oxoiron(IV) is studied. A significant Fenton-like reactivity and a remarkable accumulation of oxoiron(IV) species were observed for Fe-MoS2 . The quenching experiment was implemented to disclose the predominant role of oxoiron(IV) species in the Fe-MoS2 /H2 O2 Fenton-like system. Furthermore, oxoiron(IV) species could transform into the ⋅O2 - and 1 O2 , which further expedites the Fenton-like reaction.


Asunto(s)
Hierro , Molibdeno , Oxidación-Reducción
4.
J Sep Sci ; 43(4): 766-773, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31746547

RESUMEN

In this work, a novel, rapid, and simple analytical method was proposed for the detection of parabens in milk sample by gas chromatography coupled with mass spectrometry. At the same time, milk sample was pretreated by magnetic solid phase extraction, which detected up to five parabens. A series of important parameters of magnetic solid phase extraction were investigated and optimized, such as pH value of loading buffer, amount of material, adsorption time, ionic strength, eluting solvents, and eluting time. Under the optimized conditions, the corresponding values were more than 0.9991, limits of detection and the limit of quantification were 0.1 and 0.5 ng/mL, respectively. In addition, the recoveries were achieved in range of 95-105%, the liner range were within 0.1-600 ng/mL, and the relative standard deviations were even lower than 5%.


Asunto(s)
Conservantes de Alimentos/aislamiento & purificación , Líquidos Iónicos/química , Magnetismo/métodos , Leche/química , Parabenos/aislamiento & purificación , Extracción en Fase Sólida/métodos , Adsorción , Animales , Bovinos , Conservantes de Alimentos/química , Cromatografía de Gases y Espectrometría de Masas , Límite de Detección , Magnetismo/instrumentación , Microesferas , Parabenos/química , Extracción en Fase Sólida/instrumentación
5.
ACS Appl Mater Interfaces ; 10(31): 26539-26545, 2018 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-30016867

RESUMEN

The development of covalent organic framework (COF)-derived materials with additional functions and applications is highly desired. In this work, a unique COF-functionalized hydrophilic magnetic nanosphere (Fe3O4@PDA@TbBd) with Fe3O4 as a magnetic core, polydopamine (PDA) as a hydrophilic middle layer, and TbBd as an outer COF shell was facilely prepared as a novel hydrophilic platform for efficient detection of phthalic acid esters (PAEs). The resultant Fe3O4@PDA@TbBd nanosphere displayed strong magnetic response, high surface area, and good hydrophilicity. Accordingly, the newly synthesized COF exhibited great potential in phthalate analysis with a wide linearity (50-8000 ng/mL), good recovery (92.3-98.9%), a low limit of detection (0.0025-0.01 ng/mL), and a small relative standard deviation (for intraday less than 4.6% and for interday less than 6.8%). More excitingly, the new COF was applied to analyze nine PAEs in the human plasma sample. This work opens up new avenues for the development and application of functionalized COF-derived materials.

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