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1.
Sci Total Environ ; 865: 161235, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36586688

RESUMO

Industrial parks have a very important impact on regional economic development, but the extremely complex and relatively concentrated volatile organic compound (VOC) emissions from industrial parks also result in it being difficult to control VOCs. In this study, we took a large integrated industrial park in the upper reaches of the Yangtze River as an example, conducted a 1-year monitoring campaign of ambient air VOCs, and established a speciated VOC emission inventory based on the measured chemical profiles of the key industries. The comprehensive control index (CCI) of 125 VOCs was evaluated using the entropy weighting method based on comprehensive consideration of three aspects, namely, emission behavior, environmental effects, and health risks of VOCs, to identify priority VOC species and their key sources for VOC control in industrial parks. The total estimated VOC emissions in the industrial park in 2019 were 6446.96 t. Steel production, sewage treatment, natural gas chemical industry, pharmaceuticals, and industrial boilers were the main sources of VOC emissions. In terms of VOC components, halocarbons, aromatics, and OVOCs were the largest groups of VOCs emitted from the industrial park, accounting for 73.75 % of the total VOC emissions. Using the entropy weighting method, we evaluated the index weights of five parameters: emissions, ozone formation potential, secondary organic aerosol formation potential, hazard quotient, and lifetime cancer risk. Based on the CCI, five control levels for VOC species were further established. The VOC species in Level I and Level II, which contain species such as naphthalene, 2-chlorotoluene, benzene, acrolein, and chloroform, should be considered as extremely important priority control species. These results serve as a reference for the development of precise control strategies for VOCs in industrial parks.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Compostos Orgânicos Voláteis/análise , Monitoramento Ambiental , Ozônio/análise , Clima , China
2.
J Invest Surg ; 36(1): 2152508, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36521837

RESUMO

PURPOSE: According to international guidelines, selective lymph node dissection can be performed on patients with early-stage endometrial cancer. However, some patients at early stage have already occurred lymph node metastasis at the time of diagnosis. This study was aimed to find a method to predict the risk of lymph node metastasis in this part of patient. METHODS: We collected data from 571 patients as training cohort and 351 patients as validation cohort for this study. Then we performed univariate and multivariate analyses to confirm the correlation of frequently used factors and lymph node metastasis. Combined analysis of four commonly indicators (ERα, PR, P53 and Ki67) from pathological parameter sources was mainly carried out, and the combined ratio is defined as (ERα + PR)/(Ki67 + P53). Then the accuracy of the combined ratio and other factors in prediction were compared by AUC value. Also, the optimal truncation value was searched. Finally, patients followed up for more than two years were divided into groups by the threshold value, and their difference in survival was explored. RESULTS: This study showed that CA125, grade, LVSI, ERα, PR, P53, Ki67 have statistical significance (P-value <0.05). The AUC value of combined ratio is 0.876, which is the best. The best cutoff value of combined ratio is 1.38. CONCLUSION: The combined ratio cutoff value of 1.38 in this study can be used for prediction of risk of lymph node metastasis in early-stage endometrial cancer patients and provide a reference for therapeutic planning.


Assuntos
Neoplasias do Endométrio , Proteína Supressora de Tumor p53 , Feminino , Humanos , Metástase Linfática/diagnóstico , Metástase Linfática/patologia , Antígeno Ki-67 , Receptor alfa de Estrogênio , Linfonodos/cirurgia , Linfonodos/patologia , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/cirurgia , Excisão de Linfonodo , Estudos Retrospectivos
3.
Wei Sheng Yan Jiu ; 51(4): 645-679, 2022 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-36047272

RESUMO

OBJECTIVE: To explore the contamination characteristics of chloropropanol esters and glycidyl esters in infant formulas sold in Beijing in 2021, and to evaluate the exposure risk of chloropropanol esters and glycidyl esters for infants and toldders aged 0-36 months old. METHODS: The contents of chloropropanol esters and glycidyl esters in infant formula samples were determined using gas chromatography-mass spectrometry with deuterated internal standards. Combined with the recommended consumption of infant formulas, the exposure level of chloropropanol esters and glycidyl esters in infants and toddlers aged 0-36 months was calculated. RESULTS: The detection rate of 3-chloropropane-1, 2-diol esters(3-MCPDE), 2-chloropropane-1, 3-diol esters(2-MCPDE) and glycidyl esters in infant formulas were 98.6%, 97.1% and 95.7%, respectively. The average contents of 3-MCPDE, 2-MCPDE and glycidyl esters were 44.54, 15.65 and 12.65 µg/kg. For infant of each age groups, the daily intakes of 3-MCPDE via infant formulas by each infant groups were 0.28-0.90 µg/(kg BW), which were all lower than the tolerable daily intake(TDI, 2 µg/(kg BW));the daily intakes of 2-MCPDE via infant formulas by each infant groups were 0.10-0.29 µg/(kg BW);the exposure levels of glycidyl were 0.08-0.22 µg/(kg BW), and the margin of exposure(MOE) values were all higher than 25 000. CONCLUSION: Chloropropanol esters and glycidyl esters in infant formulas sold in Beijing from 2021 were less polluted and their intake was within the safe range.


Assuntos
alfa-Cloridrina , Pequim , Pré-Escolar , Ésteres/análise , Contaminação de Alimentos/análise , Humanos , Lactente , Fórmulas Infantis/análise , Recém-Nascido , Medição de Risco , alfa-Cloridrina/análogos & derivados , alfa-Cloridrina/análise
4.
Huan Jing Ke Xue ; 43(1): 102-112, 2022 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-34989494

RESUMO

To investigate the characteristics of atmospheric volatile organic compound (VOCs) pollution and promote VOCs pollution prevention and control in industrial areas, in December 2020, VOCs samples collected using Summa Canisters at three observation sites were used to study the characteristics of VOCs pollution and source apportionment and to conduct a health risk assessment in large integrated industrial areas and surrounding urban areas in southwest China. The results showed that the mean φ(TVOCs) at site A and site B in an industrial area and at a third urban site were 105.25×10-9, 222.92×10-9, and 82.87×10-9, respectively. Monochloromethane, dichloromethane, acetone, ethanol, and ethane were the species with higher volume fractions at the three sites. Aromatic hydrocarbons and OVOCs had a large contribution to the ozone formation potential (OFP), with a cumulative contribution of more than 50%, and the main reactive species were methyl methacrylate, toluene, p-xylene, and o-xylene; the secondary organic aerosol formation potential (SOAP) of aromatic hydrocarbons contributed more than 80%, with the main active species being toluene, p-xylene, and o-xylene. The results of PMF source analysis showed six main sources of VOCs, in the descending order of the petrochemical industry (21.83%), industrial waste incineration (18.6%), pharmaceutical manufacturing (16.99%), fossil fuel combustion (16.03%), motor vehicle exhaust (14.23%), and chemical manufacturing (12.32%). The mean values of the hazard index (HI) of site A and site B in the industrial area and in the urban site were 0.55, 0.68, and 0.41, respectively, and the mean lifetime cancer risk (LCR) values were 6.71×10-6, 6.72×10-6, and 6.58×10-6, respectively. Both HI and LCR in industrial areas were larger than those in urban areas. The quantitative assessment of risk sources showed that motor vehicle exhaust and fossil fuel combustion contributed relatively high carcinogenic risks.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , China , Monitoramento Ambiental , Resíduos Industriais , Ozônio/análise , Medição de Risco , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/toxicidade
5.
Wei Sheng Yan Jiu ; 50(6): 932-937, 2021 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-34949319

RESUMO

OBJECTIVE: To analyze the level of metal/metalloid elements and assess the health risk in drinking water in Dongcheng District of Beijing. METHODS: From 2018 to 2020, 10 kinds of metal/metalloid elements(Fe, Mn, Cu, Zn, Al, Pb, Cd, Ni, As and Se)in drinking water were detected by inductively coupled plasma-mass spectrometry(ICP-MS). The concentration of these metals were compared with the hygiene standards of drinking water. The health risk assessment model was applied from the USEPA. RESULTS: The concentration of 10 kinds of elements met the hygiene standards in all of the drinking water samples except that the zinc concentration of one sample exceeded the limit. The concentration of Al, Fe and Zn in drinking water was tens of µg/L. The concentration of Cu, Mn, Ni and Se was 1-2 µg/L or even lower. The concentration of As, Cd and Pb was basically less than 1 µg/L. The monthly average concentration of Al in drinking water showed a trend of increasing, and then decreasing in a year. The concentration of Zn decreased year by year. The 10 kinds of elements had not shown significant difference in the two water supply modes of municipal pipe network terminal water and secondary water(P>0.05). The total carcinogenic risk of elements through drinking exposure was 3.53×10~(-5). The carcinogenic risk of As was higher than that of Cd. The total non-carcinogenic risk was 9.75×10~(-8). The order of non-carcinogenic risk was: As>Se>Ni>Zn>Al>Pb>Fe>Cu>Mn>Cd. The total health risk was 3.54×10~(-5). CONCLUSION: The 10 kinds of metal/metalloid parameters of drinking water in Dongcheng District of Beijing met the hygiene standards. According to USEPA evaluation standard, the health risk assessment of elements in drinking water was acceptable.


Assuntos
Água Potável , Metaloides , Metais Pesados , Pequim , Monitoramento Ambiental , Metais Pesados/análise , Medição de Risco
6.
Materials (Basel) ; 11(6)2018 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-29904002

RESUMO

Rolling bearings play a crucial role in rotary machinery systems, and their operating state affects the entire mechanical system. In most cases, the fault of a rolling bearing can only be identified when it has developed to a certain degree. At that moment, there is already not much time for maintenance, and could cause serious damage to the entire mechanical system. This paper proposes a novel approach to health degradation monitoring and early fault diagnosis of rolling bearings based on a complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) and improved multivariate multiscale sample entropy (MMSE). The smoothed coarse graining process was proposed to improve the conventional MMSE. Numerical simulation results indicate that CEEMDAN can alleviate the mode mixing problem and enable accurate intrinsic mode functions (IMFs), and improved MMSE can reflect intrinsic dynamic characteristics of the rolling bearing more accurately. During application studies, rolling bearing signals are decomposed by CEEMDAN to obtain IMFs. Then improved MMSE values of effective IMFs are computed to accomplish health degradation monitoring of rolling bearings, aiming at identifying the early weak fault phase. Afterwards, CEEMDAN is performed to extract the fault characteristic frequency during the early weak fault phase. The experimental results indicate the proposed method can obtain a better performance than other techniques in objective analysis, which demonstrates the effectiveness of the proposed method in practical application. The theoretical derivations, numerical simulations, and application studies all confirmed that the proposed health degradation monitoring and early fault diagnosis approach is promising in the field of prognostic and fault diagnosis of rolling bearings.

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