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1.
RSC Adv ; 13(25): 17370-17383, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37304771

RESUMO

A series of new Co/N-doped porous carbon composites, denoted as Co/CZIF-9 and Co/CZIF-12, containing Co nanoparticles encapsulated in nitrogen-doped carbon matrices were prepared by annealing Co-based zeolite imidazolate framework materials, ZIF-9 and ZIF-12, as the efficient precursors at different temperatures. The structural features of the as-synthesized composites at 900 °C were determined by analytical methods with high reliability. Consequently, Co/CZIF-12_900 exhibits a high first specific discharge capacity of 971.0 mA h g-1 at a current density of 0.1 A g-1. Notably, the specific discharge/charge capacity of Co/CZIF-12_900 reaches about 508.8 mA h g-1 at 0.1 A g-1 after 100 cycles. The outstanding behaviors can be accounted for by the efficient incorporation of hetero-nitrogen doping and the Co nanoparticles within the layered structure of porous carbon, enhancing electrical conductivity and structural stability and limiting volume change during the intercalation/deintercalation of Li+ ions. These findings suggest that the Co/CZIF-12_900 material could be employed as a promising anode electrode for energy storage products.

2.
RSC Adv ; 13(16): 10650-10656, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37056968

RESUMO

Rare earth metal doping spinel ferrites offer excellent electronic, magnetic, and photocatalytic properties, but they have not been well explored for environmental mitigation. Herein, we report the facile fabrication of novel CoNd x Fe2-x O4 (x = 0-0.05) photocatalysts based on Nd3+ incorporated into CoFe2O4 for the degradation of Rhodamine B under visible light irradiation. The Nd3+ dopant considerably increased the specific surface area (35 m2 g-1) and enhanced the degradation performance (94.7%) of CoNd x Fe2-x O4 catalysts. Nd3+-doped CoFe2O4 played a role in the formation of radicals, including ˙OH, h+, and ˙O2 -. With high recyclability and performance, CoNd0.05Fe1.95O4 nanoparticles can be efficient and reusable photocatalysts for degrading organic dyes, including Rhodamine B from wastewaters.

3.
Environ Res ; 214(Pt 4): 114130, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35998691

RESUMO

The present work focused on the synthesis of novel ZnLaxFe2-xO4 catalysts (x = 0, 0.01, 0.03, 0.05) and their utilization for the photocatalytic degradation of Rhodamine B dye. Structurally, the band gap energy of the catalysts tended to decrease (1.94-1.70 eV) with increasing the amount of La3+ dopant. ZnLa0.05Fe1.95O4 had an average particle size (40 nm), high surface area (41.07 m2 g-1) and large pore volume (0.186 cm3 g-1). Moreover, the effect of doping ratio, reaction time, H2O2 concentration, catalyst loading on the treatment performance of La3+ substituted ZnFe2O4 nanocomposites was investigated. ZnLa0.05Fe1.95O4/H2O2 system exhibited the highest degradation efficiency of 99.5% and nonlinear pseudo first-order kinetic reaction rate (14.8 × 10-3 min-1) in the presence of visible light irradiation. The key role of reactive oxygen species involving •O2- and •OH radicals was well explained through the scavenger study. A plausible mechanism of the degradation of Rhodamine B dye was also proposed. Due to two advantageous points including high recyclability (up to 4 cycles) and stability, La3+ substituted ZnFe2O4 nanocomposites can be an effective and competitive catalyst for the visible light-driven photodegradation of toxic dyes in the real wastewaters.

4.
Materials (Basel) ; 12(8)2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-31013722

RESUMO

Lanthanum (La)-doped zinc oxide nanoparticles were synthesized with different La concentrations by employing a gel combustion method using poly(vinyl alcohol) (PVA). The as-synthesized photocatalysts were characterized using various techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), photoluminescence (PL) spectroscopy, and UV-visible absorption spectroscopy. The average size of ZnO nanoparticles decreased from 34.3 to 10.3 nm with increasing concentrations of La, and the band gap, as evaluated by linear fitting, decreased from 3.10 to 2.78 eV. Additionally, it was found that the photocatalytic activity of doped samples, as investigated by using methyl orange dye under visible lights, improved in response to the increase in La concentration. The decomposition of methyl orange reached 85.86% after 150 min in visible light using La0.1Zn0.9O as the photocatalyst.

5.
Mod Pathol ; 31(7): 1155-1163, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29449680

RESUMO

Inflammatory myofibroblastic tumor is a rare mesenchymal tumor occurring at many anatomic sites, with a predilection for children and young adults. Often indolent, they can be locally aggressive and can metastasize, resulting in significant morbidity and mortality. Therapeutic options are often limited. The identification of underlying kinase mutations has allowed the use of targeted therapy in a subset of patients. Unfortunately, not all tumors harbor mutations and resistance to tyrosine kinase inhibitor therapy is a potential problem. We hypothesized that these tumors may be amenable to PD-L1 therapy given the immune nature of the tumor. PD-L1 expression in inflammatory myofibroblastic tumors has not yet been defined. The purpose of this study was to explore PD-L1 expression in inflammatory myofibroblastic tumors, as adaptive PD-L1 expression is known to enrich for response to anti-PD-1/PD-L1 therapies. Expression of PD-L1 (clone SP142) was assessed in 35 specimens from 28 patients. Positivity was defined as membranous expression in ≥5% of cells and evaluated separately in tumor and immune cells. Adaptive vs. constitutive patterns of tumor cell PD-L1 expression were assessed. PD-L1 status was correlated with clinicopathologic features. CD8+ T cell infiltrates were quantified by digital image analysis. ALK status was assessed by immunohistochemistry and/or FISH. Twenty-four (69%) tumors had PD-L1(+) tumor cells and 28 (80%) showed PD-L1(+) immune cells. Most recurrent and metastatic tumors (80%) and ALK(-) tumors (88%) were PD-L1(+). Adaptive PD-L1 expression was present in 23 (96%) of PD-L1(+) tumors, which also showed a three-four fold increase in CD8+ T cell infiltration relative to PD-L1(-) tumors. Constitutive PD-L1 expression was associated with larger tumor size (p = 0.002). Inflammatory myofibroblastic tumors show frequent constitutive and adaptive PD-L1 expression, the latter of which is thought to be predictive of response to anti-PD-1. These data support further investigation into PD-1/PD-L1 blockade in this tumor type.


Assuntos
Antígeno B7-H1/biossíntese , Biomarcadores Tumorais/análise , Miofibroma/patologia , Neoplasias de Tecidos Moles/patologia , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Inflamação , Masculino , Pessoa de Meia-Idade , Miofibroma/metabolismo , Neoplasias de Tecidos Moles/metabolismo
6.
Trop Med Int Health ; 18(2): 212-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23210600

RESUMO

OBJECTIVE: To assess the out-of-pocket (OOP) payments for health-care services of HIV/AIDS patients, and identify associated factors in Vietnam. METHODS: Cross-sectional multisite survey of 1016 HIV/AIDS patients attending 7 hospitals and health centres in Ha Noi, Hai Phong and Ho Chi Minh City in 2012. RESULTS: HIV/AIDS patients used inpatient and outpatient care on average 5.1 times (95% CI = 4.7-5.4) besides ART services. Inpatient care cost US$ 461 on average and outpatient care US$ 50. Mean annual health-care expenditure for HIV/AIDS patients was US$ 188 (95% CI = 148-229). 35.1% of households (95% CI = 32.2-38.1) experienced catastrophic health expenditure; 73.3% (95% CI = 70.6-76.1) of households would be affected if ART were not subsidised. Being a patient at a provincial clinic, male sex, unstable employment, being in the poorest income quintile, a CD4 count of <200 cells/mL and not yet receiving ART increased the likelihood of catastrophic medical expense. CONCLUSIONS: HIV/AIDS patients in Vietnam frequently use medical services and incur OOP payments for health care. Scaling up free-of-charge ART services, earlier access to and initiation of ART, and decentralisation and integration of HIV/AIDS-related services could reduce their financial burden.


Assuntos
Síndrome da Imunodeficiência Adquirida/economia , Antirretrovirais/economia , Terapia Antirretroviral de Alta Atividade/economia , Infecções por HIV/economia , Custos de Cuidados de Saúde , Gastos em Saúde/estatística & dados numéricos , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Adulto , Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Estudos Transversais , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Fatores Socioeconômicos , Vietnã/epidemiologia
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