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1.
Sci Total Environ ; 920: 170964, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38369146

RESUMO

Bisphenol analogues (BPs), as one of the endocrine disruptors, have received wide attention due to their adverse impacts on ecosystems. However, the seasonal spatiotemporal distribution, source apportionment, and ecological risk of BPs in natural basins are poorly understood. Especially in highly urbanized river basins with the extensive economic development and anthropogenic activities threaten these critical but ecologically fragile regions. In this study, field investigations of BPs in the waters of the entire Qinhuai River Basin (QRB) were conducted in June (before the annual flood period) and August (after the annual flood period) 2023. The Qinhuai River, an important primary tributary of the lower Yangtze River, is located in eastern China and the QRB is characterized by a high population density and dense urbanization. Thirty-two sites were sampled for six types of BPs known to be ubiquitous in the surface water of the QRB. Significant differences in the concentrations of those BPs were found. Specifically, the concentration of total BPs (ΣBPs) was significantly higher before than after the flood period: 20.3-472 ng/L (mean = 146 ng/L) and 14.1-105 ng/L (mean = 35.9 ng/L), respectively. BPA was the main contributor to ΣBPs before the flood, and BPB followed by BPA after the flood. ΣBP concentrations were 12-241 % higher downstream than upstream of wastewater treatment plants (WWTPs). The results of a principal component analysis followed by multiple linear regression (PCA-MLR) suggested that untreated wastewater discharge from the WWTPs is an important source of BPs in the basin, with urban rainfall runoff as another potential source after the flood period. An assessment of the ecological risk of BPs, based on a calculation of the risk quotient, showed that BPA and BPS should be given due attention, and overall ecological risk of BPs pose a low risk to local algae but high and medium risks to invertebrates and fish, respectively.


Assuntos
Fenóis , Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/análise , Ecossistema , Águas Residuárias , Água/análise , Urbanização , Compostos Benzidrílicos/análise , China
3.
Comput Biol Med ; 168: 107758, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38042102

RESUMO

Convolutional neural network (CNN) has promoted the development of diagnosis technology of medical images. However, the performance of CNN is limited by insufficient feature information and inaccurate attention weight. Previous works have improved the accuracy and speed of CNN but ignored the uncertainty of the prediction, that is to say, uncertainty of CNN has not received enough attention. Therefore, it is still a great challenge for extracting effective features and uncertainty quantification of medical deep learning models In order to solve the above problems, this paper proposes a novel convolutional neural network model named DM-CNN, which mainly contains the four proposed sub-modules : dynamic multi-scale feature fusion module (DMFF), hierarchical dynamic uncertainty quantifies attention (HDUQ-Attention) and multi-scale fusion pooling method (MF Pooling) and multi-objective loss (MO loss). DMFF select different convolution kernels according to the feature maps at different levels, extract different-scale feature information, and make the feature information of each layer have stronger representation ability for information fusion HDUQ-Attention includes a tuning block that adjust the attention weight according to the different information of each layer, and a Monte-Carlo (MC) dropout structure for quantifying uncertainty MF Pooling is a pooling method designed for multi-scale models, which can speed up the calculation and prevent overfitting while retaining the main important information Because the number of parameters in the backbone part of DM-CNN is different from other modules, MO loss is proposed, which has a fast optimization speed and good classification effect DM-CNN conducts experiments on publicly available datasets in four areas of medicine (Dermatology, Histopathology, Respirology, Ophthalmology), achieving state-of-the-art classification performance on all datasets. DM-CNN can not only maintain excellent performance, but also solve the problem of quantification of uncertainty, which is a very important task for the medical field. The code is available: https://github.com/QIANXIN22/DM-CNN.


Assuntos
Medicina , Redes Neurais de Computação , Incerteza , Algoritmos , Método de Monte Carlo
4.
Med Phys ; 50(8): 4695-4709, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37402139

RESUMO

PURPOSE: High dose rate (HDR) brachytherapy rapidly delivers dose to targets with steep dose gradients. This treatment method must adhere to prescribed treatment plans with high spatiotemporal accuracy and precision, as failure to do so may degrade clinical outcomes. One approach to achieving this goal is to develop imaging techniques to track HDR sources in vivo in reference to surrounding anatomy. This work investigates the feasibility of using an isocentric C-arm x-ray imager and tomosynthesis methods to track Ir-192 HDR brachytherapy sources in vivo over time (4D). METHODS: A tomosynthesis imaging workflow was proposed and its achievable source detectability, localization accuracy, and spatiotemporal resolution were investigated in silico. An anthropomorphic female XCAT phantom was modified to include a vaginal cylinder applicator and Ir-192 HDR source (0.5 × 0.5 × 5.0 mm3 ), and the workflow was carried out using the MC-GPU Monte Carlo image simulation platform. Source detectability was characterized using the reconstructed source signal-difference-to-noise-ratio (SDNR), localization accuracy by the absolute 3D error in its measured centroid location, and spatiotemporal resolution by the full-width-at-half-maximum (FWHM) of line profiles through the source in each spatial dimension considering a maximum C-arm angular velocity of 30° per second. The dependence of these parameters on acquisition angular range (θtot = 0°-90°), number of views, angular increment between views (Δθ = 0°-15°), and volumetric constraints imposed in reconstruction was evaluated. Organ voxel doses were tallied to derive the workflow's attributable effective dose. RESULTS: The HDR source was readily detected and its centroid was accurately localized with the proposed workflow and method (SDNR: 10-40, 3D error: 0-0.144 mm). Tradeoffs were demonstrated for various combinations of image acquisition parameters; namely, increasing the tomosynthesis acquisition angular range improved resolution in the depth-encoded direction, for example from 2.5 mm to 1.2 mm between θtot = 30o and θtot = 90o , at the cost of increasing acquisition time from 1 to 3 s. The best-performing acquisition parameters (θtot = 90o , Δθ = 1°) yielded no centroid localization error, and achieved submillimeter source resolution (0.57 × 1.21 × 5.04 mm3 apparent source dimensions, FWHM). The total effective dose for the workflow was 263 µSv for its required pre-treatment imaging component and 7.59 µSv per mid-treatment acquisition thereafter, which is comparable to common diagnostic radiology exams. CONCLUSIONS: A system and method for tracking HDR brachytherapy sources in vivo using C-arm tomosynthesis was proposed and its performance investigated in silico. Tradeoffs in source conspicuity, localization accuracy, spatiotemporal resolution, and dose were determined. The results suggest this approach is feasible for localizing an Ir-192 HDR source in vivo with submillimeter spatial resolution, 1-3 second temporal resolution and minimal additional dose burden.


Assuntos
Braquiterapia , Humanos , Feminino , Dosagem Radioterapêutica , Raios X , Braquiterapia/métodos , Estudos de Viabilidade , Imagens de Fantasmas , Método de Monte Carlo
5.
Huan Jing Ke Xue ; 44(1): 463-472, 2023 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-36635834

RESUMO

The optimization of annual straw management can improve the yield, income, and carbon and nitrogen efficiency of wheat-maize double cropping systems. Based on a long-term positioning trial started in 2012, five straw management methods were considered, C100 (100% return), C75 (75% return+25% harvest), C50 (50% return+50% harvest), C25 (25% return+75% harvest), and C0 (100% harvest). We analyzed the effects of farmland carbon and nitrogen inputs and their ratios on crop yield, carbon and nitrogen use efficiency, and economic benefits in wheat and maize anniversaries with different straw managements. The results showed that: ① the amount of straw returning to the field resulted in a significant difference in carbon and nitrogen input. The annual carbon and nitrogen inputs from crop residues decreased by 1.76 t·hm-2 and 34.28 kg·hm-2, respectively, with a 25% reduction in straw returning. The C/N ratios under the C100-C0 treatment were 18.62, 17.03, 15.64, 12.54, and 9.61, respectively. ② Grain yield first increased and then decreased with the decrease in the C/N input ratio, and the effect of straw management on wheat yield was greater than that on maize. Compared with that under C100 and C0, the average grain yield of wheat and maize under the C50 treatment increased by 13.34%-13.67% and 16.10%-17.71%, respectively, and the total grain yield of wheat and maize increased by 14.98% and 15.68%. ③ The annual grain yield and carbon agronomy efficiency were the best with the C/N input ratio of 15.64 (in the C50 treatment), which were 15.71% and 0.29 kg·kg-1, respectively. The carbon production efficiency continued to increase with the decrease in the C/N input ratio, and there was a significant negative correlation between them. The nitrogen production efficiency increased first and then decreased with the decrease in the C/N input ratio. The nitrogen production efficiency of the C50 treatment was the highest (0.64 kg·kg-1), which was significantly higher than that of C100 by 32.63%. ④ The C50 treatment had the highest economic income and net income, which were 46200 yuan·hm-2 and 33400 yuan·hm-2, respectively. Compared with that of C100, the economic income of grain and straw feed increased by 5600 yuan·hm-2 and 3200 yuan·hm-2, respectively. In conclusion, the optimal C/N input ratio can be achieved by optimized straw management; 50% straw returning and 50% harvest in a wheat-maize double-cropping intensive production system can promote carbon agricultural efficiency and nitrogen production efficiency and obtain the maximum grain yield and economic benefits.


Assuntos
Carbono , Solo , Carbono/análise , Solo/química , Zea mays , Triticum , Nitrogênio , Fertilizantes , Agricultura/métodos , Grão Comestível/química , China
6.
Medicine (Baltimore) ; 100(22): e26224, 2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34087902

RESUMO

BACKGROUND: Cervicogenic headache is a secondary headache characterized by unilateral headache, symptoms, and signs of neck involvement. It is often worsened by neck movement, sustained awkward head position, or external pressure over the upper cervical or occipital region on the symptomatic side. In this systematic review, we aimed to evaluate the efficacy and safety of massage therapy for the treatment of cervicogenic headache. METHODS: We searched the China National Knowledge Infrastructure, Chinese Scientific Journal Database, Wanfang Database, China Doctoral Dissertations Full-Text Database, China Master's Theses Full-Text Database, Cochrane Central Register of Controlled Trials, PubMed, and Embase. We will select all eligible studies published on or before April 1, 2021. We will use Review Manager 5.4, provided by the Cochrane Collaborative Network for statistical analysis. We then assessed the quality and risk of the included studies and observed the outcome measures. RESULTS: This meta-analysis further confirmed the benefits of tuina in the treatment of cervicogenic headache. CONCLUSION: The purpose of this meta-analysis was to explore the effect of tuina on patients with cervicogenic headache and to provide more options for clinicians and patients to treat cervicogenic headache. ETHICS AND DISSEMINATION: This systematic review will evaluate the efficacy and safety of tuina in the treatment of cervicogenic headache. Since all the data included were published, the systematic review did not require ethical approval. REGISTRATION NUMBER: INPLASY202150053.


Assuntos
Massagem/métodos , Cefaleia Pós-Traumática/diagnóstico , Cefaleia Pós-Traumática/terapia , Adulto , Idoso , China/epidemiologia , Gerenciamento de Dados , Humanos , Pessoa de Meia-Idade , Cefaleia Pós-Traumática/fisiopatologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Segurança , Resultado do Tratamento , Metanálise como Assunto
7.
Huan Jing Ke Xue ; 39(7): 3118-3125, 2018 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-29962134

RESUMO

In order to evaluate the pollution levels of and risk from heavy metals in the atmospheric deposition of different functional urban districts, dust samples were collected from 20 sampling sites in typical industrial, traffic, residential, and educational districts of Nanjing. The concentrations of As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, Ti, V, and Zn were analyzed. The potential ecological risk and health risk were evaluated using the potential ecological risk index and U.S. EPA's health risk assessment models. Enrichment factors, correlation analysis, and principal component analysis were used to analyze the sources of heavy metals. Results showed that the concentrations of As, Cd, Co, Cr, Cu, Fe, Mn, Pb, and Zn were the highest in the industrial district and the concentrations of Ba, Ni, Ti, and V were the highest in the traffic district. The value of the potential ecological risk index was the highest in the industrial district and lowest in the educational district. Meanwhile, the ecological risk of Cr was the highest, achieving a moderate ecological hazard level. None of the studied heavy metals had noncarcinogenic risk or carcinogenic risk, according to the results of health risk assessment. Source analysis indicated that heavy metals in the atmospheric deposition from the study areas were mainly from traffic and industrial activities, coal combustion, natural process and life sources.


Assuntos
Monitoramento Ambiental , Poluição Ambiental/análise , Metais Pesados/análise , China , Poeira , Poluição Ambiental/efeitos adversos , Humanos , Metais Pesados/efeitos adversos , Medição de Risco
8.
Ecotoxicol Environ Saf ; 153: 68-77, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29407740

RESUMO

Laboratory analysis of trace metals using inductively coupled plasma (ICP) spectroscopy is not cost effective, and the complex spatial distribution of soil trace metals makes their spatial analysis and prediction problematic. Thus, for the health risk assessment of exposure to trace metals in soils, portable X-ray fluorescence (PXRF) spectroscopy was used to replace ICP spectroscopy for metal analysis, and robust geostatistical methods were used to identify spatial outliers in trace metal concentrations and to map trace metal distributions. A case study was carried out around an industrial area in Nanjing, China. The results showed that PXRF spectroscopy provided results for trace metal (Cu, Ni, Pb and Zn) levels comparable to ICP spectroscopy. The results of the health risk assessment showed that Ni posed a higher non-carcinogenic risk than Cu, Pb and Zn, indicating a higher priority of concern than the other elements. Sampling locations associated with adverse health effects were identified as 'hotspots', and high-risk areas were delineated from risk maps. These 'hotspots' and high-risk areas were in close proximity to and downwind from petrochemical plants, indicating the dominant role of industrial activities as the major sources of trace metals in soils. The approach used in this study could be adopted as a cost-effective methodology for screening 'hotspots' and priority areas of concern for cost-efficient health risk management.


Assuntos
Monitoramento Ambiental/métodos , Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Oligoelementos/análise , China , Análise Custo-Benefício , Monitoramento Ambiental/estatística & dados numéricos , Humanos , Indústrias , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Análise Espacial , Espectrometria por Raios X
9.
Huan Jing Ke Xue ; 37(5): 1662-9, 2016 May 15.
Artigo em Chinês | MEDLINE | ID: mdl-27506017

RESUMO

Contents of heavy metals involving As, Cd, Cr, Cu, Ni, Pb and Zn from atmospheric deposition in 10 parks of Nanjing were analyzed. The pollution level, ecological risk and health risk were evaluated using Geoaccumulation Index, Potential Ecological Risk Index and the US EPA Health Risk Assessment Model, respectively. The results showed that the pollution levels of heavy metals in Swallow Rock Park, Swallow Rock Park and Mochou Lake Park were higher than the others. Compared to other cities such as Changchun, Wuhan and Beijing, the contents of heavy metals in atmospheric deposition of parks in Nanjing were higher. The evaluation results of Geoaccumulation Index showed that Pb was at moderate pollution level, Zn and Cu were between moderate and serious levels, while Cd was between serious and extreme levels. The ecological risk level of Cd was high. The assessment results of Health Risk Assessment Model indicated that there was no non-carcinogenic risk for all the seven heavy metals. For carcinogenic risk, the risks of Cd, Cr and Ni were all negligible (Risk < 1 x 10⁻6), whereas As had carcinogenic risk possibility but was considered to be acceptable (10⁻6 < Risk < 10⁻4).


Assuntos
Monitoramento Ambiental , Metais Pesados/análise , Medição de Risco , Poluentes do Solo/análise , China , Cidades , Ecologia , Modelos Teóricos , Parques Recreativos
10.
Sci Total Environ ; 569-570: 1545-1552, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27395080

RESUMO

BACKGROUND: Ambient fine particulate matter (PM2.5) pollution is currently a most severe and worrisome environmental problem in China. However, current knowledge of the health effects of this pollution is insufficient. OBJECTIVES: This study aims to provide an overall understanding regarding the long-term mortality effects of current PM2.5 pollution in China and the potential health benefits of realizing the goals stipulated in the ongoing action plan of Air Pollution Prevention and Control (APPC) and the targets suggested by the WHO. METHODS: Three typical causes and all-cause of PM2.5-related mortality were considered. The log-linear exposure-response function was adopted, and a meta-analysis was used to determine the exposure-response coefficients, based on newly available data in China and abroad. RESULTS: In the 74 leading cities of China, approximately 32% of the reported deaths, with a mortality rate of 1.9‰, were associated with PM2.5 in 2013, in which deaths from cardiovascular, respiratory and lung-cancer causes accounted for 20% of the reported deaths, with a mortality rate of 1.2‰. The regional difference is remarkable for the mortalities and proportions of the different causes. If the PM2.5 concentration goals of the APPC plan, the first interim and the guideline targets of the WHO could be achieved, the PM2.5-related all-cause mortality would be reduced by 25%, 64% and 95%, respectively, compared with that of 2013. CONCLUSIONS: PM2.5 pollution in China has incurred great health risks that are even worse than those of tobacco smoking. The health benefits of the APPC plan could be outstanding, although there is still great potential to improve future air quality.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , Exposição Ambiental/efeitos adversos , Material Particulado/efeitos adversos , População Urbana , China , Monitoramento Ambiental , Humanos , Modelos Teóricos , População Urbana/estatística & dados numéricos
11.
Ecotoxicol Environ Saf ; 128: 161-70, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26938154

RESUMO

Arsenic, Cd, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn total concentrations and bioaccessibilities in 15 urban park dust samples were determined. The oral bioaccessibility measured by the Simple Bioaccessibility Extraction Test (SBET) decreased in the order of Pb>Cd>Zn>Mn>Cu>Co>V>Ni>As>Cr. The Tomlinson pollution load index (PLI) and geoaccumulation index (I(geo)) were calculated to evaluate the pollution extent to which the samples were contaminated. Sources were identified using principal component analysis and Pb isotope compositions. Most elements except Co and V were considered to mainly originate from anthropogenic sources. Non-carcinogenic and carcinogenic risks to humans through urban park dust exposure were assessed using the oral bioaccessibilities of the elements. Ingestion was the main pathway for non-carcinogenic risk. The hazard quotients were below the safe level (=1) for all elements, however, Pb (0.154) and As (0.184) posed potential higher risks to children than adults. The carcinogenic effects occurring were below the acceptable level (10(-4)) for As and <10(-6) for Cd, Co, Cr, and Ni.


Assuntos
Arsênio/análise , Poeira/análise , Poluição Ambiental/análise , Metais Pesados/análise , Parques Recreativos , Oligoelementos/análise , Adulto , Criança , China , Cidades , Humanos , Parques Recreativos/normas , Medição de Risco
12.
Risk Anal ; 35(2): 265-77, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25109941

RESUMO

Point source pollution is one of the main threats to regional environmental health. Based on a water quality model, a methodology to assess the regional risk of point source pollution is proposed. The assessment procedure includes five parts: (1) identifying risk source units and estimating source emissions using Monte Carlo algorithms; (2) observing hydrological and water quality data of the assessed area, and evaluating the selected water quality model; (3) screening out the assessment endpoints and analyzing receptor vulnerability with the Choquet fuzzy integral algorithm; (4) using the water quality model introduced in the second step to predict pollutant concentrations for various source emission scenarios and analyzing hazards of risk sources; and finally, (5) using the source hazard values and receptor vulnerability scores to estimate overall regional risk. The proposed method, based on the Water Quality Analysis Simulation Program (WASP), was applied in the region of the Taipu River, which is in the Taihu Basin, China. Results of source hazard and receptor vulnerability analysis allowed us to describe aquatic ecological, human health, and socioeconomic risks individually, and also integrated risks in the Taipu region, from a series of risk curves. Risk contributions of sources to receptors were ranked, and the spatial distribution of risk levels was presented. By changing the input conditions, we were able to estimate risks for a range of scenarios. Thus, the proposed procedure may also be used by decisionmakers for long-term dynamic risk prediction.


Assuntos
Medição de Risco/métodos , Rios , Poluição da Água , Qualidade da Água , Algoritmos , China , Humanos , Modelos Teóricos , Método de Monte Carlo , Medição de Risco/estatística & dados numéricos , Rios/química , Poluentes Químicos da Água/análise , Poluição da Água/efeitos adversos , Poluição da Água/análise , Poluição da Água/prevenção & controle
13.
Environ Manage ; 55(3): 523-35, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25537155

RESUMO

Public participation in environmental management is critically important in the development of a healthy environmental governance system. However, public participation has not been well institutionalized in China and the public's role in environmental management is limited. Chinese policy-makers and researchers currently face a dilemma wherein they must determine how to fully and effectively involve the public. This paper aims to contribute an innovative approach that can effectively engage the general public, allowing them to participate more in China's environmental management. In this paper, we first review the current status of environmental management and public participation in China. Based on China's political and socio-cultural-legal dynamics, an Environmental Community Consultative Group (ECCG) was developed to be an innovative means to engage community members. A pilot study of the ECCG was carried out in Yapu village of Changzhou City in Jiangsu Province. The evaluation of the process and outcome of the ECCG showed that the group's effectiveness and influence were significant; the ECCG model was a powerful means by which to promote public environmental awareness, improve public environmental behavior and facilitate public engagement in environmental management. But the ECCG is a small local group that may not function well regarding more complex issues covering a much larger area and has limited impact on environmental policy making. The ECCG experience offers the prospect of grassroots involvement in environmental protection for China's rural areas, while also laying the foundation for further research on community participation in environmental management.


Assuntos
Participação da Comunidade/métodos , Conservação dos Recursos Naturais/legislação & jurisprudência , Formulação de Políticas , China , Humanos , Projetos Piloto
14.
Int J Environ Res Public Health ; 9(12): 4504-21, 2012 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-23222206

RESUMO

In recent years, water quality degradation associated with rapid socio-economic development in the Taihu Lake Basin, China, has attracted increasing attention from both the public and the Chinese government. The primary sources of pollution in Taihu Lake are its inflow rivers and their tributaries. Effective water environmental management strategies need to be implemented in these rivers to improve the water quality of Taihu Lake, and to ensure sustainable development in the region. The aim of this study was to provide a basis for water environmental management decision-making. In this study, the QUAL2K model for river and stream water quality was applied to predict the water quality and environmental capacity of the Hongqi River, which is a polluted tributary in the Taihu Lake Basin. The model parameters were calibrated by trial and error until the simulated results agreed well with the observed data. The calibrated QUAL2K model was used to calculate the water environmental capacity of the Hongqi River, and the water environmental capacities of COD(Cr) NH(3)-N, TN, and TP were 17.51 t, 1.52 t, 2.74 t and 0.37 t, respectively. The results showed that the NH(3)-N, TN, and TP pollution loads of the studied river need to be reduced by 50.96%, 44.11%, and 22.92%, respectively to satisfy the water quality objectives. Thus, additional water pollution control measures are needed to control and reduce the pollution loads in the Hongqi River watershed. The method applied in this study should provide a basis for water environmental management decision-making.


Assuntos
Monitoramento Ambiental/métodos , Recuperação e Remediação Ambiental/métodos , Poluição Química da Água/prevenção & controle , Qualidade da Água/normas , China , Simulação por Computador , Tomada de Decisões , Modelos Teóricos , Rios/química , Poluição Química da Água/análise
15.
Sci Total Environ ; 431: 278-85, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22687438

RESUMO

In recent years, water quality degradation associated with rapid socio-economic development in the Taihu Lake Basin, China, has attracted increasing attention from both the public and the Chinese government. The primary sources of pollution in Taihu Lake are its inflow rivers and their tributaries. Effective water quality improvement programs need to be implemented in these rivers to improve the water quality of Taihu Lake, and to ensure sustainable development in the region. To ensure effectiveness and efficiency, it is important that the optimal water quality improvement program for a specific situation be selected. The aim of this study was to facilitate the selection of this optimal program. The QUAL2K model for river and stream water quality was used to simulate the effects of a range of water quality improvement scenarios in the Hongqi River, which is a polluted tributary in the Taihu Lake Basin. These scenarios consisted of a series of three water treatment technologies in different configurations, from upstream to downstream. The results showed that the optimal scenario comprised a bio-contact oxidation system upstream, followed by an ecological floating bed, and a vertical moveable eco-bed downstream. The reduction rates achieved by this scenario for biochemical oxygen demand (BOD), ammonia nitrogen (NH(3)-N), total nitrogen (TN), and total phosphorus (TP) were 49.50%, 32.81%, 35.94%, and 45.27%, respectively. The QUAL2K model proved to be an effective tool in the comparative evaluation of potential water quality improvement programs. The method applied in this study can prevent the implementation of water quality improvement programs that would not achieve the desired goals.


Assuntos
Água Doce , Modelos Teóricos , Qualidade da Água , China , Simulação por Computador , Monitoramento Ambiental , Programas Governamentais , Lagos , Nitrogênio , Fósforo , Rios , Poluição da Água/prevenção & controle
16.
Int J Environ Res Public Health ; 8(5): 1368-87, 2011 05.
Artigo em Inglês | MEDLINE | ID: mdl-21655125

RESUMO

Approximately 30,000 dams in China are aging and are considered to be high-level risks. Developing a framework for analyzing spatial multicriteria flood risk is crucial to ranking management scenarios for these dams, especially in densely populated areas. Based on the theories of spatial multicriteria decision analysis, this report generalizes a framework consisting of scenario definition, problem structuring, criteria construction, spatial quantification of criteria, criteria weighting, decision rules, sensitivity analyses, and scenario appraisal. The framework is presented in detail by using a case study to rank dam rehabilitation, decommissioning and existing-condition scenarios. The results show that there was a serious inundation, and that a dam rehabilitation scenario could reduce the multicriteria flood risk by 0.25 in the most affected areas; this indicates a mean risk decrease of less than 23%. Although increased risk (<0.20) was found for some residential and commercial buildings, if the dam were to be decommissioned, the mean risk would not be greater than the current existing risk, indicating that the dam rehabilitation scenario had a higher rank for decreasing the flood risk than the decommissioning scenario, but that dam rehabilitation alone might be of little help in abating flood risk. With adjustments and improvement to the specific methods (according to the circumstances and available data) this framework may be applied to other sites.


Assuntos
Técnicas de Apoio para a Decisão , Inundações , Colapso Estrutural , China , Modelos Teóricos , Medição de Risco/métodos
17.
Nan Fang Yi Ke Da Xue Xue Bao ; 29(2): 274-7, 2009 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-19246298

RESUMO

OBJECTIVE: To understand the characteristics of adenovirus infection in hospitalized children with pneumonia in Guangzhou area. METHODS: The infection rate, hospitalization time and hospitalization expenses of adenovirus-infected hospitalized children with pneumonia in Guangzhou area from 2005 to 2007 were analyzed. RESULTS: The total adenovirus infection rate was 6.04% in these children, with a male to female ratio of 1.47:1, showing significantly higher infection rate in female (7.92%) than in male patients (5.21%, P<0.05). The hospital stay and hospitalization costs between male and female children showed no significant difference (P>0.05). Adenovirus-infected children from birth to six years old accounted for 90.50% of the total adenovirus-infected children, and the infection rate in 0 to 1-year-old children (3.71%) was significantly lower than that in elder children (P<0.05). Although the infection rate in winter (8.44%) was significantly higher than that in the other seasons (P<0.05), the cases from March to August accounted for 60.11% of the total infected cases. Furthermore, the infection rate in 2007 (4.31%) was significantly lower than that in 2005 and 2006 (7.11% and 6.71%, respectively, P<0.05). CONCLUSION: Adenovirus infection is an important pathogen in hospitalized children with pneumonia in Guangzhou area, and the infection rates differed between gender, age, season and the years.


Assuntos
Infecções por Adenovirus Humanos/epidemiologia , Pneumonia/virologia , Infecções por Adenovirus Humanos/economia , Adolescente , Criança , Pré-Escolar , China/epidemiologia , Efeitos Psicossociais da Doença , Feminino , Hospitalização , Humanos , Incidência , Lactente , Masculino , Pneumonia/economia , Estações do Ano , Fatores Sexuais
18.
Nan Fang Yi Ke Da Xue Xue Bao ; 28(6): 930-2, 2008 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-18583230

RESUMO

OBJECTIVE: To evaluate the value of the myocardial biochemical markers including creatine kinase MB isoenzyme (CK-MB), cardiac isoform of Tropnin-T (cTnT) and N-termimal pro-brain natriuretic peptide (NT-proBNP) and electrocardiogram (ECG) in monitoring the cardiotoxicity of recombinant human endostatin (rh-endostatin) in cancer patients. METHODS: Forty cancer patients were divided into two groups and received rh-endostatin in addition to chemotherapy (group A, n=24) or chemotherapy only (Group B, n=24). Serum CK-MB, cTnT levels and plasma NT-proBNP levels were measured and the ECG was recorded in all the patients before and after each of the two therapy cycles. RESULTS: In group A, serum CK-MB, cTnT and plasma NT-proBNP levels were significantly increased after the treatment in comparison with the baseline levels (P<0.05), but such increment was not observed in group B (P>0.05). With comparable baseline levels of CK-MB, cTnT and NT-proBNP before the treatment (P>0.05), patients in group A showed significantly higher levels of the indices than those in group B after each therapy cycle (P<0.05). Increased ECG abnormality were observed after rh-endostatin treatment in Group A (P<0.05) at a rate significantly higher than that of Group B after the second treatment cycle (P<0.05). CONCLUSION: Rh-endostatin has definite cardiotoxicity, and detection of the myocardial biochemical markers of CK-MB, cTnT and NT-proBNP may help predict the occurrence of cardiotoxicity.


Assuntos
Biomarcadores Tumorais/sangue , Endostatinas/uso terapêutico , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Creatina Quinase Forma MB/sangue , Endostatinas/efeitos adversos , Endostatinas/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/tratamento farmacológico , Fragmentos de Peptídeos/sangue , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Medição de Risco , Troponina T/sangue
19.
J Opt Soc Am A Opt Image Sci Vis ; 24(2): 423-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17206257

RESUMO

Currently, we are developing a computational optical biopsy technology for molecular sensing. We use the diffusion equation to model photon propagation but have a concern about the accuracy of diffusion approximation when the optical sensor is close to a bioluminescent source. We derive formulas to describe photon fluence for point and ball sources and measurement formulas for an idealized optical biopsy probe. Then, we numerically compare the diffusion approximation and the radiative transport as implemented by Monte Carlo simulation in the cases of point and ball sources. Our simulation results show that the diffusion approximation can be accurately applied if mu's>>mu(a) even if the sensor is very close to the source (>1mm). Furthermore, an approximate formula is given to describe the measurement of a cut-end fiber probe for a ball source.


Assuntos
Óptica e Fotônica , Tomografia Óptica/métodos , Pesquisa Biomédica , Biópsia , Difusão , Humanos , Modelos Teóricos , Método de Monte Carlo , Fótons , Espalhamento de Radiação , Software , Tomografia Óptica/instrumentação
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