Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Huan Jing Ke Xue ; 45(3): 1349-1360, 2024 Mar 08.
Artículo en Chino | MEDLINE | ID: mdl-38471851

RESUMEN

Pollution variation, source characteristics, and meteorological effects of water-soluble inorganic ions (WSIIs) in PM2.5 were analyzed in Xinxiang city, Henan Province. PM2.5 samples and their chemical components were monitored online by using URG-9000 in four seasons:winter (January, 2022), spring (April, 2022), summer (July, 2022), and fall (October, 2022). The results showed that the TWSIIs had the same seasonal fluctuations as PM2.5. The average seasonal concentrations of WSIIs ranged from 19.62-72.15 µg·m-3, accounting for more than 60% of PM2.5, demonstrating that WSIIs were the major components of PM2.5. The annual concentration value of NO3-/SO42- was 2.11, which showed an increasing trend, suggesting predominantly mobile sources for secondary inorganic aerosols (SNA). Further, the molar concentration value [NH4+]/[NO3-] was 1.95, demonstrating that agriculture emissions were the dominant contributors to atmospheric nitrogen. Furthermore, the backward trajectory analysis showed that the concentrations of Ca2+ and Mg2+ were higher when the northeasterly wind prevailed and the wind speed was high. High values of SOR and NOR were correlated with low temperatures and high relative humidity (T < 8℃, RH > 60%), demonstrating that more gaseous precursors were converted into sulfate and nitrate. At high temperatures (T > 24℃), there was no apparent high NOR value like that for SOR, mainly due to the decomposition of NH4NO3 at high temperatures. Finally, backward trajectories associated with the PMF-resolved results were used to explore the regional transport characteristics. The results illustrated that dust sources in the study areas were mainly influenced by air trajectories originating from the northwest regions, whereas secondary sulfate, secondary nitrate, and biomass sources contributed more to WSIIs when wind speed and altitude air masses were low in the area surrounding the observation site.

2.
Medicine (Baltimore) ; 102(42): e35602, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37861503

RESUMEN

BACKGROUND: Major orthopedic surgery, including hip and knee replacement and lower extremity trauma fractures surgery, is associated with a high risk of venous thromboembolism (VTE), especially proximal deep vein thrombosis (DVT), and pulmonary embolism (PE), and is linked with high morbidity and mortality rates. Chemical anticoagulation is routinely used to prevent VTE, with previous meta-analyses reporting on the efficacy and safety of aspirin and other anticoagulants, however, opinions are divided. In the past 2 years, several large randomized controlled trials have been published, therefore, we reanalyzed aspirin efficacy and safety when compared with other anticoagulants in preventing VTE in major orthopedic surgery. METHODS: Using PubMed, The Cochrane Library, Embase, and Web of Science databases, we conducted a RCT search in August 2023. The main outcomes included VTE, proximal DVT or PE. Additional outcomes included bleeding events, wound complications, wound infections, blood transfusions, and death events. RESULTS: In total, 17 eligible articles, involving 29,522 patients (15,253 aspirin vs 14,269 other anticoagulant cases), were included. Primary outcomes showed that VTE incidence was more high in the aspirin group when compared with other anticoagulants (risk ratio [RR] = 1.45, 95% confidence interval [CI] = 1.18-1.77, P = .0004) and proximal in the aspirin group the DVT and/or PE incidence was significantly higher in the aspirin group when compared with other anticoagulants (RR = 1.19, 95% CI = 1.02-1.39, P = .03). No significant secondary outcome differences were identified in the aspirin group when compared with other anticoagulants (bleeding events [RR] = 0.83, 95% CI = 0.63-1.10, P = .20); wound complications (RR = 0.45, 95% CI = 0.20-1.04, P = .06); wound infection (RR = 1.08, 95% CI = 0.85-1.38, P = .53); blood transfusion events (RR = 1.00, 95% CI = 0.84-1.19, P = 1.00) and death events (RR = 1.11, 95% CI = 0.78-1.57, P = .55). CONCLUSIONS: Our updated meta-analysis showed that aspirin was inferior to when compared with other anticoagulants in VTE-related orthopedic major surgery, including proximal DVT and/or PE, and was more likely to form VTE. No differences between groups were identified for bleeding, wound complications, wound infections, transfusion, or death events.


Asunto(s)
Procedimientos Ortopédicos , Embolia Pulmonar , Tromboembolia Venosa , Trombosis de la Vena , Infección de Heridas , Humanos , Aspirina/efectos adversos , Tromboembolia Venosa/prevención & control , Ensayos Clínicos Controlados Aleatorios como Asunto , Trombosis de la Vena/epidemiología , Trombosis de la Vena/prevención & control , Anticoagulantes/efectos adversos , Hemorragia , Embolia Pulmonar/prevención & control , Procedimientos Ortopédicos/efectos adversos , Heparina de Bajo-Peso-Molecular
3.
ACS Appl Mater Interfaces ; 14(24): 28123-28132, 2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35679596

RESUMEN

The photocatalytic production of syngas from CO2 and water is an attractive and straightforward way for both solar energy storage and sustainable development. Here, we combined the hybrid shell of a bimetallic metal-organic framework (MOF) Zn/Co-zeolitic imidazolate framework (ZIF) and the hybrid photoactive center of Ni-doped CdS nanoparticles (Ni@CdS) to construct a new "2 + 2" photocatalysis system Ni@CdS⊂Zn/Co-ZIF through a facile self-assembly process, which exhibited a double-synergic effect for visible light harvesting and CO2 conversion, leading to one of the highest photocatalytic syngas production rates and excellent recyclability. The H2/CO of syngas ratios can be readily adjusted by controlling the ratio of Zn/Co in the hybrid MOF shell.

4.
Huan Jing Ke Xue ; 42(9): 4140-4150, 2021 Sep 08.
Artículo en Chino | MEDLINE | ID: mdl-34414712

RESUMEN

This study analyzed the seasonal variation, sources, and source-specific health risks of PM2.5-bound metals in Xinxiang city, Henan province. A total of 112 daily PM2.5 samples were collected over four consecutive seasons during 2019-2020. In total, 19 elements were identified using inductively coupled plasma atomic emission spectroscopy (ICP-AES). The annual concentrations of PM2.5 and 11 heavy metals were calculated to be (66.25±35.73) µg·m-3 and (1.32±0.84) µg·m-3, respectively. Strong seasonal variations were observed in PM2.5 concentrations and the concentrations of associated metal elements, with the lowest concentrations all occurring in summer. The highest concentrations of dust-related elements (e.g., Al, Ca, Fe, Mg,and Ti) were recorded in spring, differing significantly from other elements, which all exhibited the highest mass concentrations in winter. The results apportioned from positive matrix factorization (PMF) and potential source contribution function (PSCF) models showed that the major sources of PM2.5-bound elements were Ni-and Co-related emissions (5.8%), motor vehicles (13.7%), Cd-related emissions(5.1%), combustion emissions (18.2%), and dust (57.3%). Health risk models showed that there were no obvious non-carcinogenic risks associated with these metals, because their hazard quotient (HQ) values were all below 1. Lifetime carcinogenic risks of the five apportioned sources were all higher than the acceptable level (1×10-6). Of these five sources, combustion emissions were the largest contributors to cancer risk (8.74×10-6, 36.9%) and non-cancer risk (0.60, 25.6%). This study suggests that control strategies to mitigate exposure risk in Xinxiang should emphasize reducing the sources of combustion emissions.


Asunto(s)
Metales Pesados , Material Particulado , Clima , Monitoreo del Ambiente , Humanos , Metales Pesados/análisis , Material Particulado/efectos adversos , Material Particulado/análisis , Estaciones del Año
5.
Inorg Chem ; 60(15): 11626-11632, 2021 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-34291940

RESUMEN

Metal-organic frameworks (MOFs) represent an ideal platform for the construction of highly active composite catalysts. However, loading metastable and/or multicomponent metal compounds into MOFs remains a synthetic bottleneck due to the great challenge of keeping the guest and matrix intact during the preparation of a composite. In this work, we develop a new impregnation reduction surface modification (IRSM) strategy to give a new composite catalyst CuCl@MIL-101(Cr), which is successfully postmodified by in situ construction of CuII defects on the surface of loaded CuCl inside MOF pores, leading to the new composite material CuII/CuI@MIL-101(Cr). The new dual-component composite catalyst exhibits a hierarchical structure and superior catalytic activity in C-C homocoupling of arylboronic acids under green conditions. This study presents a facile strategy for improving the catalytic activity by constructing defects on the surface of MOF-based catalysts as well as for forming multiple-component composite materials.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...