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1.
Toxics ; 12(6)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38922057

RESUMO

Air pollution is one of the major global public health challenges. Using annual fine particulate matter (PM2.5) concentration data from 2016 to 2021, along with the global exposure mortality model (GEMM), we estimated the multi-year PM2.5-pollution-related deaths divided by different age groups and diseases. Then, using the VSL (value of statistical life) method, we assessed corresponding economic losses and values. The number of deaths attributed to PM2.5 in Beijing in 2021 fell by 33.74 percent from 2016, while health economic losses would increase by USD 4.4 billion as per capita disposable income increases year by year. In 2021, the average annual concentration of PM2.5 in half of Beijing's municipal administrative districts is less than China's secondary ambient air quality standard (35 µg/m3), but it can still cause 48,969 deaths and corresponding health and economic losses of USD 16.31 billion, equivalent to 7.9 percent of Beijing's GDP. Therefore, it is suggested that more stringent local air quality standards should be designated to protect public health in Beijing.

2.
Environ Sci Pollut Res Int ; 29(54): 81703-81712, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35739449

RESUMO

Civil aviation is an important source of air pollutants, but this field has received insufficient attention in China. Based on the standard emissions model of the International Civil Aviation Organization (ICAO) and actual flight information from 241 airports, this study estimated a comprehensive emissions inventory for 2010-2020 by considering the impacts of mixing layer height. The results showed that annual pollutant emissions rapidly trended upward along with population and economic growth; however, the emissions decreased owing to the impacts of the COVID-19 pandemic. In 2020, the emissions of carbon monoxide (CO), nitrogen oxides (NOX), particulate matter (PM), methane (CH4), nitrous oxide (N2O), carbon dioxide (CO2), and water vapor (H2O) were 34.34, 65.73, 0.10, 0.34, 0.40, 14,706.26, and 5733.11 Gg, respectively. The emissions of total volatile organic compounds (VOCs) from China's civil airports in 2020 were estimated at 17.20 Gg; the major components were formic acid (1.70 Gg), acetic acid (1.62 Gg), 1-butylene (1.03 Gg), acetone (0.96 Gg), and acetaldehyde (0.93 Gg). The distribution of pollutant emissions was consistent with the level of economic development, mainly in Beijing, Guangzhou, and Shanghai. In addition, we estimated future pollution trends for the aviation industry under four scenarios. Under the comprehensive scenario, which considered the impacts of economic growth, passenger turnover, cargo turnover, COVID-19, and technological efficiency, the levels of typical pollutants were expected to increase by nearly 1.51-fold from 2010 to 2035.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Gases de Efeito Estufa , Compostos Orgânicos Voláteis , Humanos , Poluentes Atmosféricos/análise , Aeroportos , Poluição do Ar/análise , Dióxido de Carbono/análise , Compostos Orgânicos Voláteis/análise , Monóxido de Carbono/análise , Óxido Nitroso , Acetona , Vapor , Pandemias , Monitoramento Ambiental/métodos , China , Material Particulado/análise , Metano/análise , Acetaldeído
3.
Quant Imaging Med Surg ; 12(5): 2830-2840, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35502384

RESUMO

Background: Autologous fat grafting is a procedure that treats soft tissue defects by reallocating fat to improve a patient's physical appearance. Imaging methods may be used to evaluate and monitor the grafted fat after transplantation. The goal of imaging is to examine the signal and volume of the grafted fat after autologous fat grafting during the adipose tissue recovery. However, researchers have yet to examine the feasibility of using fat-only imaging to assess the autologous fat graft. Methods: In this prospective and observational study, 46 injected sides in 23 female patients (age 35±7.8 years) were included in the image evaluation. The patients underwent autologous fat grafting surgery with filtered and washed fat. A total of 16, 18, and 12 sides were scanned 7 days, 3 months, and 1 year after fat grafting, respectively. Fat-only images were obtained using Dixon imaging, and then the image quality and contrast of the T1W and T2W were rated to evaluate the application of this method when imaging the autologous fat. The signal and volume of the autologous fat graft were recorded to assess the retention during recovery of the autologous fat tissue. Results: Fat-only T1W magnetic resonance imaging (MRI) was used to identify and delineate grafted fat because this method had better image quality and image differentiation than did T2W MRI. The average signal contrast and retention rate measured 7 days postoperation (28.8%±4.7%; 94.1%±5.8%) was the highest and then decreased at 3 months (16.3%±2.1%; 48.7%±17.3%) and 1 year (3.3%±1.3%, 33.1%±12.9%) after surgery. There were statistically significant differences between the signal and volume retention measurements at each postoperative recovery phase. Conclusions: The T1W fat-only images produced by Dixon MRI is a feasible approach for identifying grafted fat and measure postoperative changes during clinical evaluation. We found a significant decrease in signal contrast and volume of the grafted fat from the surgery date to 3 months postoperation and from 3 months to 1-year postoperation.

4.
Materials (Basel) ; 14(23)2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34885528

RESUMO

Geopolymer concrete (GPC) has drawn widespread attention as a universally accepted ideal green material to improve environmental conditions in recent years. The present study systematically quantifies and compares the environmental impact of fly ash GPC and ordinary Portland cement (OPC) concrete under different strength grades by conducting life cycle assessment (LCA). The alkali activator solution to fly ash ratio (S/F), sodium hydroxide concentration (CNaOH), and sodium silicate to sodium hydroxide ratio (SS/SH) were further used as three key parameters to consider their sensitivity to strength and CO2 emissions. The correlation and influence rules were analyzed by Multivariate Analysis of Variance (MANOVA) and Gray Relational Analysis (GRA). The results indicated that the CO2 emission of GPC can be reduced by 62.73%, and the correlation between CO2 emission and compressive strength is not significant for GPC. The degree of influence of the three factors on the compressive strength is CNaOH (66.5%) > SS/SH (20.7%) > S/F (9%) and on CO2 emissions is S/F (87.2%) > SS/SH (10.3%) > CNaOH (2.4%). Fly ash GPC effectively controls the environmental deterioration without compromising its compressive strength; in fact, it even in favor.

5.
Ying Yong Sheng Tai Xue Bao ; 31(2): 554-562, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32476349

RESUMO

The key ecological function area plays an important role in providing ecosystem service. As the main players of economic activities in this area, the excessive dependence of local farmers on environmental resource will seriously influence ecological environment quality, and thus impair the ecosystem service. At present, it is urgent to explore the dependence of farmers' livelihoods on environmental resource and its influencing factors in key ecological function areas, which would provide reference for the formulation of environmental friendly regional development policies. We selected the Gannan Plateau as study area. Based on 581 survey data, we analyzed the dependence of farmers' livelihood on environmental resource, and used the ordinal multi-class Logistic regression model to identify its key impact factors. The results showed that local farmers were highly dependent on environmental resource in Gannan Plateau, which was mainly reflected in three aspects of food self-sufficiency, daily energy consumption and income source, with the dependence of 57.3%, 56.9% and 37.4%, respectively. There were significant differences in the dependence of different types of farmers' livelihoods on environmental resource, in that farmers with higher levels of education and higher non-agricultural levels had lower dependence and the farmers with high dependency ratio were more dependent on environmental resources. The factors including family dependency ratio, labor education level, proportion of migrant workers in labor force, family member leadership, ecological policy, and altitude had significant impact on farmers' environmental resource dependence. Among them, family dependency ratio and altitude had positive impact on it, while the proportion of migrant workers in labor force, labor education level, family member leadership, ecological policy had negative impact.


Assuntos
Ecossistema , Fazendeiros , Agricultura , China , Política Ambiental , Humanos
6.
Acad Radiol ; 27(11): 1572-1579, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31954606

RESUMO

RATIONALE AND OBJECTIVES: To prospectively compare the image quality (IQ) and lesion detection performance of reduced field-of-view (rFOV) and full FOV (fFOV) diffusion-weighted imaging (DWI) sequences in detecting insulinomas. MATERIALS AND METHODS: From October 2017 to September 2018, 67 patients with suspected insulinomas were prospectively enrolled and underwent imaging with both types of DWI sequences. The slice thickness (4 mm) and slice gaps (1 mm) were the same for the two DWI sequences, and the TR/TE was 2235/56 ms for the rFOV sequence and 1892/63 ms for the fFOV sequence. Three radiologists independently assessed the imaging quality (IQ) subjectively with a 5-point scale and objectively with signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) measurements. The IQ scores, CNR, SNR, lesion detection rates, and ADC values were compared. Receiver operating characteristic curves were generated, and the area under the curve (AUC) was used to compare the diagnostic performance. RESULTS: Fifty patients were tumor positive, with 65 tumors (size: 1.31 ± 0.77 cm, range: 0.6-5.8 cm). The IQ score, SNR, and CNR were significantly higher for rFOV DWI than for fFOV DWI (IQ: 3.64 ± 0.487 vs 3.310 ± 0.577, SNR: 22.520 ± 8.690 vs 10.284 ± 3.321, CNR: 3.454 ± 2.642 vs 1.327 ± 2.801, and all p < 0.05). For lesions less than 1.5 cm (n = 55), the lesion detection rates of the rFOV were statistically improved compared to those of the fFOV (90.7% vs. 75.9%, p = 0.039). The sensitivity of lesion detection was significantly improved with the rFOV-DWI sequences compared to that with the fFOV-DWI sequences (0.924 vs. 0.773, p = 0.013). The ADC values of the two DWI sequences were consistent for insulinomas and normal parenchyma. CONCLUSION: Considering the improvements in overall IQ and lesion detection and the consistency of ADC measurements, we suggest that rFOV DWI is a reliable auxiliary alternative to fFOV DWI for clinical practice in the detection of pancreatic insulinomas.


Assuntos
Insulinoma , Neoplasias Pancreáticas , Imagem de Difusão por Ressonância Magnética , Imagem Ecoplanar , Humanos , Insulinoma/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
World J Gastroenterol ; 24(18): 2024-2035, 2018 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-29760545

RESUMO

AIM: To assess the accuracy of Look-Locker on gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) for staging liver fibrosis in chronic hepatitis B/C (CHB/C). METHODS: We prospectively included 109 patients with CHB or CHC who underwent a 3.0-Tesla MRI examination, including T1-weighted and Look-Locker sequences for T1 mapping. Hepatocyte fractions (HeF) and relaxation time reduction rate (RE) were measured for staging liver fibrosis. A receiver operating characteristic analysis using the area under the receiver operating characteristic curve (AUC) was used to compare the diagnostic performance in predicting liver fibrosis between HeF and RE. RESULTS: A total of 73 patients had both pathological results and MRI information. The number of patients in each fibrosis stage was evaluated semiquantitatively according to the METAVIR scoring system: F0, n = 23 (31.5%); F1, n = 19 (26.0%); F2, n = 13 (17.8%); F3, n = 6 (8.2%), and F4, n = 12 (16.4%). HeF by EOB enhancement imaging was significantly correlated with fibrosis stage (r = -0.808, P < 0.05). AUC values for diagnosis of any (≥ F1), significant (≥ F2) or advanced (≥ F3) fibrosis, and cirrhosis (F4) using HeF were 0.837 (0.733-0.913), 0.890 (0.795-0.951), 0.957 (0.881-0.990), and 0.957 (0.882-0.991), respectively. HeF measurement was more accurate than use of RE in establishing liver fibrosis staging, suggesting that calculation of HeF is a superior noninvasive liver fibrosis staging method. CONCLUSION: A T1 mapping-based HeF method is an efficient diagnostic tool for the staging of liver fibrosis.


Assuntos
Hepatite B Crônica/patologia , Hepatite C Crônica/patologia , Cirrose Hepática/diagnóstico por imagem , Fígado/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Meios de Contraste/administração & dosagem , Estudos Transversais , Feminino , Gadolínio DTPA/administração & dosagem , Hepatite B Crônica/diagnóstico por imagem , Hepatite B Crônica/virologia , Hepatite C Crônica/diagnóstico por imagem , Hepatite C Crônica/virologia , Humanos , Fígado/diagnóstico por imagem , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC
8.
Magn Reson Imaging ; 48: 34-41, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29278765

RESUMO

To assess the value of T1ρ,T1ρ on hepatobiliary phase (HBP) and diffusion metrics in staging of Non-alcoholic fatty liver disease (NAFLD) activity scores, inflammation, fibrosis in NASH rabbits model. Non-alcoholic steatohepatitis (NASH) rabbits model was induced by feeding a varied duration of high-fat, high-cholesterol diet. T1ρ,T1ρ (HBP) 20min after administration of Gd-EOB-DTPA, and Intravoxel incoherent motion imaging (IVIM) diffusion-weighted imaging were performed on a 3.0T magnetic resonance (MR) imaging unit. The diagnostic value of each parameter for NAS, inflammation and fibrosis severity were determined. T1ρ (r=0.658) and T1ρ (HBP) (r=0.750) have strong association with NASH overall activity, T1ρ (HBP) is strongly relevant to inflammation stage (r=0.812). There was negative association between f and inflammation (r=-0.480), whilst no significant relation between other three parameters (apparent diffusion coefficient (ADC), pseudo-diffusion coefficient (D*) and true diffusion coefficient (D)) and inflammation or overall activity. The areas under the receiver operating characteristic curves (AUCs) of f, ADC, T1ρ and T1ρ-HBP were 0.871, 0.728, 0.849 and 0.949 for differentiating NASH; 0.731, 0.552, 0.925 and 0.922 for G2-3 inflammation; and 0.767, 0.625, 0.816, and 0.882 for S1-2 fibrosis. Comparison of ROC curve showed T1ρ (HBP) had an optimal diagnostic performance for NASH [T1ρ (HBP) vs ADC, AUC:0.949 vs 0.728, P=0.043], inflammation [T1ρ (HBP) vs ADC, AUC:0.922 vs 0.552, P=0.003], fibrosis [T1ρ (HBP) vs ADC, AUC:0.882 vs 0.625, P=0.046]. The combination of T1ρ (HBP)+perfusion fraction (f) showed highest diagnostic value for NASH (AUC:0.971), inflammation (AUC:0.935). Among T1ρ imaging and IVIM diffusion metrics, combination of T1rho (HBP)+f was found to be superior noninvasive imaging biomarker for NASH activity assessment.


Assuntos
Gadolínio DTPA , Aumento da Imagem/métodos , Inflamação/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/patologia , Animais , Área Sob a Curva , Imagem de Difusão por Ressonância Magnética/métodos , Modelos Animais de Doenças , Humanos , Inflamação/patologia , Fígado/diagnóstico por imagem , Fígado/patologia , Masculino , Curva ROC , Coelhos
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