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1.
Small ; 17(50): e2103052, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34719844

RESUMEN

Manganese dioxide (MnO2 ), with naturally abundant crystal phases, is one of the most active candidates for toluene degradation. However, it remains ambiguous and controversial of the phase-activity relationship and the origin of the catalytic activity of these multiphase MnO2 . In this study, six types of MnO2 with crystal phases corresponding to α-, ß-, γ-, ε-, λ-, and δ-MnO2 are prepared, and their catalytic activity toward ozone-assisted catalytic oxidation of toluene at room temperature are studied, which follow the order of δ-MnO2  > α-MnO2  > ε-MnO2  > γ-MnO2  > λ-MnO2  > ß-MnO2 . Further investigation of the specific oxygen species with the toluene oxidation activity indicates that high catalytic activity of MnO2 is originated from the rich oxygen vacancy and the strong mobility of oxygen species. This work illustrates the important role of crystal phase in determining the oxygen vacancies' density and the mobility of oxygen species, thus influencing the catalytic activity of MnO2 catalysts, which sheds light on strategies of rational design and synthesis of multiphase MnO2 catalysts for volatile organic pollutants' (VOCs) degradation.


Asunto(s)
Nanoestructuras , Ozono , Catálisis , Compuestos de Manganeso , Óxidos , Tolueno
2.
Top Stroke Rehabil ; : 1-10, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39140651

RESUMEN

OBJECTIVES: The purpose of this study was to assess the effects of family resilience, caregiver needs, and caregiver readiness on benefit finding for family caregivers of patients with stroke and to examine the mediating role of caregiver needs and caregiver readiness between family resilience and benefit finding. METHODS: In this cross-sectional study, convenience sampling was designed and used to recruit participants from three general hospitals in Jinan, Shandong Province, China, from February to September 2022, in which 340 participants completed the General Information Questionnaire, Chinese version of the Family Resilience Assessment Scale (C-FRAS), Caregiver Needs Assessment Scale (CNAS) Chinese version of the Caregiver Preparedness Scale (C-CPS), and Caregiver Benefit Finding Scale (CBFS). Model 6 in process version 4.0 was used to test the chain mediation model between family resilience and benefit finding for caregiver needs and caregiver readiness. RESULTS: Correlation analysis showed that benefit finding in family caregivers was positively associated with family resilience and caregiver readiness and negatively associated with caregiver needs; mediation model tests showed that the total indirect effect of family resilience on benefit finding was 0.163, with the specific mediating effects of caregiver needs and caregiver readiness accounting for 33.74% and 59.51%, and the chain mediating effect of both accounting for 6.75%. CONCLUSIONS: Family resilience not only directly influences benefit finding for family caregivers but also indirectly affects benefit finding through caregiver needs and caregiver readiness. Caregiver needs and caregiver readiness have a mediating role between family resilience and benefit finding in family caregivers.

3.
Front Public Health ; 11: 992197, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36908482

RESUMEN

Background: The resources available to fight an epidemic are typically limited, and the time and effort required to control it grow as the start date of the containment effort are delayed. When the population is afflicted in various regions, scheduling a fair and acceptable distribution of limited available resources stored in multiple emergency resource centers to each epidemic area has become a serious problem that requires immediate resolution. Methods: This study presents an emergency medical logistics model for rapid response to public health emergencies. The proposed methodology consists of two recursive mechanisms: (1) time-varying forecasting of medical resources and (2) emergency medical resource allocation. Considering the epidemic's features and the heterogeneity of existing medical treatment capabilities in different epidemic areas, we provide the modified susceptible-exposed-infected-recovered (SEIR) model to predict the early stage emergency medical resource demand for epidemics. Then we define emergency indicators for each epidemic area based on this. By maximizing the weighted demand satisfaction rate and minimizing the total vehicle travel distance, we develop a bi-objective optimization model to determine the optimal medical resource allocation plan. Results: Decision-makers should assign appropriate values to parameters at various stages of the emergency process based on the actual situation, to ensure that the results obtained are feasible and effective. It is necessary to set up an appropriate number of supply points in the epidemic emergency medical logistics supply to effectively reduce rescue costs and improve the level of emergency services. Conclusions: Overall, this work provides managerial insights to improve decisions made on medical distribution as per demand forecasting for quick response to public health emergencies.


Asunto(s)
Urgencias Médicas , Epidemias , Humanos , Salud Pública
4.
Chemosphere ; 247: 125864, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31931318

RESUMEN

In this work, a series of δ-MnO2/USY with different contents of δ-MnO2 (0.3 wt%, 1.5 wt%, 3.0 wt%, 10.0 wt%, and 15.0 wt%) were prepared. In addition, their performances of the adsorption of toluene, degradation and mineralization of toluene, and removal of ozone (O3) were investigated. The results showed that, among all the samples, 3.0 wt% δ-MnO2/USY displayed the best performance of toluene adsorption, degradation and mineralization. Furthermore, according to the in situ DRIFTS and GC-MS analysis, the intermediate by-products during the toluene degradation progress were ascertained and the possible pathway of catalytic oxidation toluene by δ-MnO2/USY in the presence of O3 was proposed.


Asunto(s)
Compuestos de Manganeso/química , Óxidos/química , Ozono/análisis , Tolueno/análisis , Compuestos Orgánicos Volátiles/análisis , Zeolitas/química , Adsorción , Catálisis , Modelos Teóricos , Oxidación-Reducción , Propiedades de Superficie , Temperatura
5.
World Neurosurg ; 95: 148-155, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27506403

RESUMEN

OBJECTIVE: To determine any differences in self-reported dysphagia in patients treated with single-level anterior cervical decompression with different zero-profile implants (arthroplasty vs. arthrodesis) and identify risk factors for postoperative dysphagia. METHODS: A total of 112 patients with 1-level cervical degenerative disc disease were included in the prospective study. The dysphagia conditions and radiologic results were assessed using Bazar dysphagia scoring system, the Swallowing Quality of Life scores, cervical alignment (CA), segmental angle, and prevertebral soft tissues swelling (PSTS). All these parameters were compared before and after surgery in the respective group, which were also compared between the 2 groups. Correlations between the confounding factors and postoperative dysphagia were analyzed. RESULTS: No significant differences existed in preoperative or initially postoperative dysphagia rate and scores between the 2 groups (P > 0.05). However, the dysphagia rate and scores of cervical disc arthroplasty was better than those of fusion at postoperative day 7. Heavy smoker, PSTS change (≥5 mm), or CA change (≥5 degrees) was prone to have postoperative dysphagia. CONCLUSIONS: Postoperative dysphagia remains a common incidence, despite advances in instrumentation technologies. However, cervical disc arthroplasty is superior to anterior cervical discectomy and fusion in ameliorating the symptom of dysphagia in the early postoperative term. Heavy smoker, PSTS change (≥5 mm), and CA change (≥5 degrees) were important predictors of postoperative dysphagia.


Asunto(s)
Vértebras Cervicales/cirugía , Descompresión Quirúrgica , Trastornos de Deglución/epidemiología , Discectomía , Degeneración del Disco Intervertebral/cirugía , Complicaciones Posoperatorias/epidemiología , Fusión Vertebral , Reeemplazo Total de Disco , Adulto , Artroplastia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Prótesis e Implantes , Factores de Riesgo
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