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1.
Heliyon ; 10(4): e26499, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38404763

RESUMO

Accurately portraying the mechanism of the flow of natural resource consumption between regions and its impact on ecology is of crucial value in deepening the understanding of the coordinated relationship between population, resources, environment and development. Consequently, this promotes the sustainable development of the natural economy and society. Based on a regional-industrial perspective, this study used a localized three-dimensional ecological footprint model to measure and decompose natural resources in Xinjiang from 2005 to 2020. In doing so, the study clarified the supply, demand, and flow utilization of natural capital in Xinjiang, the balance of spatial and temporal allocation of resources, the coupling between economic growth and resource consumption, and the coordination between industrial structure and ecological environment. The results showed that (1) Xinjiang's per capita ecological deficit grew from 2.096 to 11.667 in 2005-2020. Moreover, the energy footprint was a decisive part of the ecological deficit throughout the study period. Furthermore, the trend of increased ecological pressure was higher in northern and eastern Xinjiang than in southern Xinjiang. (2) The overall Gini coefficient of Xinjiang's ecological carrying capacity was at the critical value of spatial equilibrium (0.4), with differences between the groups: Northern & Southern Xinjiang > Northern & Eastern Xinjiang > Eastern & Southern Xinjiang. The reasons for this inter-regional economic disparity are related to fiscal expenditure/GDP, level of urbanization, and regional industrial output. Overall, the decoupling relationship between environmental pressures and economic growth was optimistic. (3) From an industrial perspective, the levels of industrial structural efficiency and the industrial ecological harmony index were still relatively low, but the overall trend was on the rise. (4) Resource endowment, economic development, consumption structure, and population had significant driving effects on the ecological footprint, whereas environmental protection, science, and technology could inhibit its growth to a certain extent. This study aimed to provide an in-depth analysis of the current situation and problems of natural resource use in Xinjiang and provide theoretical and practical references for sustainable development in the region.

2.
Front Public Health ; 10: 1024491, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36504946

RESUMO

Background: Against a backdrop of aging and declining birthrates, the demand for long-term care insurance (LTCI) systems in various countries throughout the world continues to rise. Most traditional LTCI systems only cover a limited group of people, which cannot solve the problem of nursing needs among other groups, and, further, it makes financial sustainability very difficult to achieve. Purpose: This article aims to explore how Nantong successfully achieves both "full coverage" and "financial sustainability" through institutional innovation. Objects: Institutional innovation logic and financial sustainability of LTCI system in Nantong, one prefecture-level city with the highest degree of aging in China. Methods: Through field interviews and research, this article examines the LTCI system in Nantong, exploring its logic and its successful realization of institutional innovation, which combines international and local experience. The study further uses quantitative methods to measure the system's financial sustainability. Data: From the seventh national population census bulletin, the 13th Five-Year population development plan, the Nantong Municipal Bureau of Statistics and Nantong Statistical Yearbook 2020 from Nantong government. And from the authors' field survey data in the Medical Insurance Bureau of Nantong. Results: The findings reveal that the Nantong model effectively disperses institutional risks by means of horizontal and vertical transfer payments, diversified financing, and service outsourcing, achieving its dual goals of full coverage and financial sustainability in the long run. Conclusion: Nantong Model has interrupted the path dependence of traditional dual systems and the philosophy of fragmented institutional construction. Nantong's path-breaking institutional construction paradigm has important theoretical and practical value. Contributions: The experience of Nantong may prove valuable and instructive, for not only other cities in China but also developing countries across the globe.


Assuntos
Envelhecimento , Seguro de Assistência de Longo Prazo , Humanos , Censos , China , Cidades
3.
Sensors (Basel) ; 22(14)2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35890887

RESUMO

Global Navigation Satellite System (GNSS) signals generate slant tropospheric delays when they pass through the atmosphere, which is recognized as the main source of error in many spatial geodetic applications. The zenith tropospheric delay (ZTD) derived from radio occultation data is of great significance to atmospheric research and meteorology and needs to be assessed in the use of precision positioning. Based on the atmPrf, sonPrf, and echPrf data from the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) Data Analysis and Archiving Center (CDAAC) from 1 January to 31 December 2008 and 2012, we obtained the ZTDs of the radio occultation data (occZTD) and the corresponding radiosonde (sonZTD) and ECWMF data (echZTD). The ZTDs derived from ground-based global positioning system (GPS) observations from the International GNSS Service (IGS) were corrected to the lowest tangent point height of the matched radio occultation profile by the barometric height formula (gnsZTD). The statistical results show that the absolute values of the bias between occZTD and echZTD, sonZTD, or gnsZTD are less than 5 mm, and the standard deviations are approximately 20 mm or less, indicating that occZTD had significant accuracy in the GNSS positioning model even when the local spherical symmetry assumption error was introduced when the Abel inversion algorithm was used to obtain the refractive index profile of atmPrf. The effects of the horizontal/vertical matching resolution and the variation in the station height/latitude on the biases of occZTD and gnsZTD were analyzed. The results can be used to quantify the performance of radio occultation data for tropospheric delay error correction in dynamic high-precision positioning.

4.
Int Urol Nephrol ; 54(12): 3263-3270, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35789973

RESUMO

OBJECTIVES: Dry weight assessment (DWA) is an important part of dialysis and fluid management in patients receiving renal replacement therapy. With the development of bioimpedance analysis (BIA), the development of the direct segmental multi-frequency BIA (DSM-BIA) has provided a more convenient measure for DWA of dialysis patients, but its accuracy remains unclear. This study was designed to evaluate the application of DSM-BIA in DWA of continuous ambulatory peritoneal dialysis (CAPD) patients. DESIGN: This is a cross-sectional study. Using the conventional BIA as a reference, we examined the accuracy of the DSM-BIA technique for assessing dry weight in CAPD patients and analyzed the potential factors influencing their fluid volume status. SETTING AND PARTICIPANTS: A total of 31 patients with end-stage renal disease receiving CAPD and 310 healthy volunteers were recruited for this study. METHODS: The intraclass correlation coefficients (ICC) and Bland-Altman plots were used to assess the consistency between DSM-BIA and the conventional BIA for DWA. Univariate and multivariate linear regression analyses were used to explore the influencing factors associated with the edema index. RESULTS: DSM-BIA and the conventional BIA technology were consistent in DWA in CAPD patients (ICC female 0.972, ICC male 0.882, ICC total 0.960). Similarly, Bland-Altman plots showed good agreements between the two methods in DWA for both genders. Univariate and multivariate linear regression analysis showed both eGFR level (P = 0.04) and serum NT-pro BNP concentration (P = 0.007) were positively correlated with the ratio of extracellular water to total body water (ECW/TCW). CONCLUSIONS: DSM-BIA in DWA has good accuracy in clinical applications and has potential application value for fluid volume management in CAPD patients.


Assuntos
Falência Renal Crônica , Diálise Peritoneal Ambulatorial Contínua , Feminino , Humanos , Masculino , Diálise Peritoneal Ambulatorial Contínua/efeitos adversos , Impedância Elétrica , Estudos Transversais , Falência Renal Crônica/complicações , Água
5.
Environ Sci Pollut Res Int ; 28(32): 43853-43871, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33837944

RESUMO

This study evaluated the quality of groundwater and its suitability for drinking and irrigation in the hilly area of the Taihang Mountains in Henan Province, China. Groundwater samples were collected from 43 unconfined and 20 confined wells and analyzed. The pollution index of groundwater (PIG) was estimated based on the physicochemical parameters, and seven indices, including the sodium adsorption ratio (SAR), sodium percentage (%Na), residual sodium carbonate (RSC), permeability index (PI), magnesium ratio (MR), Kelley's ratio (KR), and corrosivity ratio (CR), were calculated to qualify the groundwater within the research area for irrigation activities. Multivariate statistical techniques were performed to better understand the hydrochemical processes. Chemical analysis showed that the dominant cation and anion were Ca2+ and HCO3-, respectively, and the principal hydrochemical facies was Ca-Mg-HCO3. In terms of pH, total dissolved solids, Na+, Cl-, F-, and SO42-, most samples were well within the limits prescribed by Chinese standards for drinking water quality, but more than half of the unconfined samples exceeded the specified limits for total hardness and nitrate. The PIG values suggested the pollution level was insignificant for all confined water samples and 72.09% of unconfined water samples, but the PIG distribution map showed that the water in the south central part of the study area had low to moderate pollution. According to the computed values of SAR, %Na, RSC, PI, KR, and MR and the results of a salinity diagram, the results further indicated that most of the studied samples were appropriate for irrigation usage. Only the CR values rendered 41.86% of the unconfined samples and 20% of the confined samples unfit for irrigation. Hence, proper measures are needed to resolve the corrosivity problem. Factor analysis resulted in the extraction of 3 factors that explained 81% of the data variability, and the extracted factors pointed towards geogenic factors governing the groundwater quality.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , China , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Qualidade da Água
6.
Int J Cancer ; 147(9): 2416-2423, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32356305

RESUMO

We examined whether automated visual evaluation (AVE), a deep learning computer application for cervical cancer screening, can be used on cervix images taken by a contemporary smartphone camera. A large number of cervix images acquired by the commercial MobileODT EVA system were filtered for acceptable visual quality and then 7587 filtered images from 3221 women were annotated by a group of gynecologic oncologists (so the gold standard is an expert impression, not histopathology). We tested and analyzed on multiple random splits of the images using two deep learning, object detection networks. For all the receiver operating characteristics curves, the area under the curve values for the discrimination of the most likely precancer cases from least likely cases (most likely controls) were above 0.90. These results showed that AVE can classify cervix images with confidence scores that are strongly associated with expert evaluations of severity for the same images. The results on a small subset of images that have histopathologic diagnoses further supported the capability of AVE for predicting cervical precancer. We examined the associations of AVE severity score with gynecologic oncologist impression at all regions where we had a sufficient number of cases and controls, and the influence of a woman's age. The method was found generally resilient to regional variation in the appearance of the cervix. This work suggests that using AVE on smartphones could be a useful adjunct to health-worker visual assessment with acetic acid, a cervical cancer screening method commonly used in low- and middle-resource settings.


Assuntos
Colo do Útero/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Programas de Rastreamento/instrumentação , Smartphone/economia , Displasia do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/prevenção & controle , Biópsia , Colo do Útero/patologia , Conjuntos de Dados como Assunto , Aprendizado Profundo , Diagnóstico Diferencial , Feminino , Humanos , Programas de Rastreamento/economia , Programas de Rastreamento/métodos , Curva ROC , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/patologia
7.
Environ Sci Pollut Res Int ; 27(6): 6278-6299, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31865575

RESUMO

This paper investigates the interaction effects of income inequality and democracy on CO2 emissions. The spatial panel model, which accounts for the spatial spillover effects across countries, is used. Using the panel data covering 41 Belt and Road initiative countries, the results indicate significant positive spatial spillovers effect to country-level CO2 emission activity. The Kuznets Curve hypothesis, which assumes that reverse U relation presents between income and CO2 emissions, is identified. Empirical results provide evidence that democracy levels promote the nonlinear nexus between income inequality and CO2 emissions. High levels of inequality, ceteris paribus, in conjunction with poor democratic institutions are likely to result in higher pollution. The findings are robust to various robustness tests.


Assuntos
Dióxido de Carbono , Democracia , Desenvolvimento Econômico , Poluição Ambiental , Renda , Fatores Socioeconômicos
8.
Huan Jing Ke Xue ; 40(8): 3489-3500, 2019 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854754

RESUMO

Trace polycyclic aromatic hydrocarbons (PAHs) in drinking water sources have significant harmful effects on human health. Water and sediment samples from water source regions of three water treatment plants in Guangzhou were collected and the distributions of 16 kinds of PAHs were analyzed. The human risk of PAHs in the water samples was also evaluated using the Risk Assessment Guidance for Superfund (RAGS) of the United States Environmental Protection Agency (USEPA). The results showed that PAHs in the samples from the three water source regions did not exceed the corresponding standard limit for water quality, and the content of ΣPAHs in suspended solids and sediments was below the medium level. The non-carcinogenic risks (HQ and HI) of PAHs in the water samples were less than 1, and the non-carcinogenic risk was negligible. In addition, Riskingest, Riskdermal, and RiskT for the waters were all in range of 5.53×10-7 to 5.34×10-6, indicating that a carcinogen risk was possible but acceptable. The results of the isomer ratio method indicated that the PAHs in the water sources of the three water plants had a mixed input of pollution, including petroleum discharge, petroleum combustion, and incomplete combustion of wood, coal, and biomass. The total organic carbon (TOC) content of the water and sediment samples was positively correlated with the accumulation and enrichment of low-ring PAHs, and there was a significant positive correlation between PAHs and similar molecules in the sediments. The ΣPAHs in the water and sediment samples were also strongly correlated.


Assuntos
Saúde Ambiental , Hidrocarbonetos Policíclicos Aromáticos , Medição de Risco , Poluentes Químicos da Água , China , Monitoramento Ambiental , Sedimentos Geológicos , Humanos , Abastecimento de Água
9.
Plast Reconstr Surg ; 144(5): 760e-769e, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31373991

RESUMO

BACKGROUND: With advancing age, Asian women are often plagued by lateral hooding of the upper eyelid skin, eyebrow ptosis, and obvious periorbital wrinkles. The authors propose a novel technique to revive the natural eyelid shape with a stable eyebrow position and alleviate periorbital wrinkles in Asian women. METHODS: Sixty-six patients underwent subbrow blepharoplasty combined with periorbital muscle manipulation. An ellipse shape of the skin and subcutaneous tissue below the eyebrow was measured, demarcated, and removed. Then, the orbicularis oculi muscle beneath the subcutaneous tissue was exposed and dissected at the upper third. The lower muscle flap was fixed to the supraorbital rim periosteum and the upper musculocutaneous flaps, forming a cross flap for interlocking fixation. The lateral border of the orbicularis oculi muscle was detached from the subcutaneous tissue, splayed out, and sutured upward and inward to the periosteum. The corrugator supercilii muscle temporal to the origin of the supraorbital nerve notch was separated by 1 to 2 mm. The operation results were evaluated by patient satisfaction and comparisons between preoperative and postoperative photographs. RESULTS: Subbrow blepharoplasty combined with periorbital muscle manipulation significantly corrected lateral hooding with a stable eyebrow position and reduced the crow's feet and glabellar frown lines in all patients. The persistence of the improved outcome was stable during the follow-up period. Postoperative scarring was inconspicuous; however, eight cases had transient postoperative forehead numbness. CONCLUSIONS: This novel procedure provides a simple, effective, and comprehensive technique for improving periorbital aging in Asian women. The surgical outcomes are predictable, and the postoperative scarring is inconspicuous. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.


Assuntos
Povo Asiático/estatística & dados numéricos , Blefaroplastia/métodos , Pálpebras/cirurgia , Músculos Faciais/cirurgia , Satisfação do Paciente/estatística & dados numéricos , Fotografação/métodos , Adulto , Idoso , Estudos de Coortes , Estética , Sobrancelhas , Feminino , Testa/cirurgia , Humanos , Pessoa de Meia-Idade , Cuidados Pré-Operatórios/métodos , Prognóstico , Rejuvenescimento , Estudos Retrospectivos , Medição de Risco , Envelhecimento da Pele , Resultado do Tratamento
10.
Medicine (Baltimore) ; 98(21): e15810, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31124981

RESUMO

The prevalence of overweight-obesity has increased sharply among undergraduates worldwide. In 2016, approximately 52% of adults were overweight-obese. This cross-sectional study aimed to investigate the prevalence of overweight-obesity and explore in depth the connection between eating habits and overweight-obesity among Chinese undergraduates.The study population included 536 undergraduates recruited in Shijiazhuang, China, in 2017. They were administered questionnaires for assessing demographic and daily lifestyle characteristics, including sex, region, eating speed, number of meals per day, and sweetmeat habit. Anthropometric status was assessed by calculating the body mass index (BMI). The determinants of overweight-obesity were investigated by the Pearson χ test, Spearman rho test, multivariable linear regression, univariate/multivariate logistic regression, and receiver operating characteristic curve analysis.The prevalence of undergraduate overweight-obesity was 13.6%. Sex [male vs female, odds ratio (OR): 1.903; 95% confidence interval (95% CI): 1.147-3.156], region (urban vs rural, OR: 1.953; 95% CI: 1.178-3.240), number of meals per day (3 vs 2, OR: 0.290; 95% CI: 0.137-0.612), and sweetmeat habit (every day vs never, OR: 4.167; 95% CI: 1.090-15.933) were significantly associated with overweight-obesity. Eating very fast was positively associated with overweight-obesity and showed the highest OR (vs very slow/slow, OR: 5.486; 95% CI: 1.622-18.553). However, the results of multivariate logistic regression analysis indicated that only higher eating speed is a significant independent risk factor for overweight/obesity (OR: 17.392; 95% CI, 1.614-187.363; P = .019).Scoremeng = 1.402 × scoresex + 1.269 × scoreregion + 19.004 × scoreeatin speed + 2.546 × scorenumber of meals per day + 1.626 × scoresweetmeat habit and BMI = 0.253 × Scoremeng + 18.592. These 2 formulas can help estimate the weight status of undergraduates and predict whether they will be overweight or obese.


Assuntos
Índice de Massa Corporal , Dieta/efeitos adversos , Indicadores Básicos de Saúde , Obesidade/etiologia , Sobrepeso/etiologia , Adolescente , China/epidemiologia , Estudos Transversais , Comportamento Alimentar , Feminino , Humanos , Estilo de Vida , Modelos Lineares , Masculino , Refeições , Análise Multivariada , Obesidade/epidemiologia , Razão de Chances , Sobrepeso/epidemiologia , Valor Preditivo dos Testes , Prevalência , Curva ROC , Fatores de Risco , População Rural/estatística & dados numéricos , Estatísticas não Paramétricas , Estudantes/estatística & dados numéricos , Inquéritos e Questionários , Universidades , População Urbana/estatística & dados numéricos , Adulto Jovem
11.
Mar Drugs ; 17(1)2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30634484

RESUMO

Asperlin is a marine-derived, natural product with antifungal, anti-inflammatory and anti-atherosclerotic activities. In the present study, we showed that asperlin effectively prevented the development of obesity in high-fat diet (HFD)-fed mice. Oral administration of asperlin for 12 weeks significantly suppressed HFD-induced body weight gain and fat deposition without inhibiting food intake. Hyperlipidemia and liver steatosis were also substantially ameliorated. A respiratory metabolism monitor showed that asperlin efficiently increased energy expenditure and enhanced thermogenic gene expression in adipose tissue. Accordingly, asperlin-treated mice showed higher body temperature and were more tolerant of cold stress. Meanwhile, asperlin also increased the diversity and shifted the structure of gut microbiota. Oral administration of asperlin markedly increased the relative abundance of Bacteroidetes, leading to a higher Bacteroidetes-to-Fimicutes ratio. The HFD-induced abnormalities at both phylum and genus levels were all remarkably recovered by asperlin. These results demonstrated that asperlin is effective in preventing HFD-induced obesity and modulating gut microbiota. Its anti-obesity properties may be attributed to its effect on promoting energy expenditure.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Metabolismo Energético/efeitos dos fármacos , Compostos de Epóxi/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Obesidade/prevenção & controle , Pironas/farmacologia , Administração Oral , Animais , Compostos de Epóxi/administração & dosagem , Fígado Gorduroso/induzido quimicamente , Fígado Gorduroso/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pironas/administração & dosagem
12.
BMC Bioinformatics ; 19(1): 3, 2018 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-29298666

RESUMO

BACKGROUND: Running multiple-chain Markov Chain Monte Carlo (MCMC) provides an efficient parallel computing method for complex Bayesian models, although the efficiency of the approach critically depends on the length of the non-parallelizable burn-in period, for which all simulated data are discarded. In practice, this burn-in period is set arbitrarily and often leads to the performance of far more iterations than required. In addition, the accuracy of genomic predictions does not improve after the MCMC reaches equilibrium. RESULTS: Automatic tuning of the burn-in length for running multiple-chain MCMC was proposed in the context of genomic predictions using BayesA and BayesCπ models. The performance of parallel computing versus sequential computing and tunable burn-in MCMC versus fixed burn-in MCMC was assessed using simulation data sets as well by applying these methods to genomic predictions of a Chinese Simmental beef cattle population. The results showed that tunable burn-in parallel MCMC had greater speedups than fixed burn-in parallel MCMC, and both had greater speedups relative to sequential (single-chain) MCMC. Nevertheless, genomic estimated breeding values (GEBVs) and genomic prediction accuracies were highly comparable between the various computing approaches. When applied to the genomic predictions of four quantitative traits in a Chinese Simmental population of 1217 beef cattle genotyped by an Illumina Bovine 770 K SNP BeadChip, tunable burn-in multiple-chain BayesCπ (TBM-BayesCπ) outperformed tunable burn-in multiple-chain BayesCπ (TBM-BayesA) and Genomic Best Linear Unbiased Prediction (GBLUP) in terms of the prediction accuracy, although the differences were not necessarily caused by computational factors and could have been intrinsic to the statistical models per se. CONCLUSIONS: Automatically tunable burn-in multiple-chain MCMC provides an accurate and cost-effective tool for high-performance computing of Bayesian genomic prediction models, and this algorithm is generally applicable to high-performance computing of any complex Bayesian statistical model.


Assuntos
Genoma , Modelos Genéticos , Animais , Teorema de Bayes , Bovinos , China , Cadeias de Markov , Método de Monte Carlo , Polimorfismo de Nucleotídeo Único
13.
J Pathol Inform ; 7: 51, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28163974

RESUMO

BACKGROUND: In previous research, we introduced an automated, localized, fusion-based approach for classifying uterine cervix squamous epithelium into Normal, CIN1, CIN2, and CIN3 grades of cervical intraepithelial neoplasia (CIN) based on digitized histology image analysis. As part of the CIN assessment process, acellular and atypical cell concentration features were computed from vertical segment partitions of the epithelium region to quantize the relative distribution of nuclei. METHODS: Feature data was extracted from 610 individual segments from 61 images for epithelium classification into categories of Normal, CIN1, CIN2, and CIN3. The classification results were compared against CIN labels obtained from two pathologists who visually assessed abnormality in the digitized histology images. In this study, individual vertical segment CIN classification accuracy improvement is reported using the logistic regression classifier for an expanded data set of 118 histology images. RESULTS: We analyzed the effects on classification using the same pathologist labels for training and testing versus using one pathologist labels for training and the other for testing. Based on a leave-one-out approach for classifier training and testing, exact grade CIN accuracies of 81.29% and 88.98% were achieved for individual vertical segment and epithelium whole-image classification, respectively. CONCLUSIONS: The Logistic and Random Tree classifiers outperformed the benchmark SVM and LDA classifiers from previous research. The Logistic Regression classifier yielded an improvement of 10.17% in CIN Exact grade classification results based on CIN labels for training-testing for the individual vertical segments and the whole image from the same single expert over the baseline approach using the reduced features. Overall, the CIN classification rates tended to be higher using the training-testing labels for the same expert than for training labels from one expert and testing labels from the other expert. The Exact class fusion- based CIN discrimination results obtained in this study are similar to the Exact class expert agreement rate.

14.
Huan Jing Ke Xue ; 37(8): 3007-3016, 2016 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964726

RESUMO

The distribution characteristics and pollution degrees of 20 organochlorine pesticides (OCPs) were investigated in surface sediments from Zhelin Bay south of China and the ecological risk of OCPs and integrated ecological risk at the samples stations in sediments were evaluated by risk quotient (RQ) and sediment quality guideline of NOAA. The possible sources of HCHs and DDTs in sediments were preliminarily studied, and the correlation between OCPs and sediment characteristic parameters was discussed. The concentrations of DDTs in surface sediments were found to be higher than those of other OCPs, especially p,p'-DDD, and the concentrations of DDTs were higher than the limited values of Chinese Marine sediment quality criteria. The total concentration of 20 OCPs in surface sediments ranged from 14.14 to 306.88 ng·g-1, with a mean concentration of 78.37 ng·g-1, and the highest total concentration was at site 8(S8). There were inevitable adverse biological effects and high ecological risk of p,p'-DDD and p,p'-DDT, high integrated ecological risk at S8 and S10. The possible sources of HCHs in surface sediments of Zhelin Bay were mainly from the application of Lindane pesticides. At S1,S2,S10,S11 there was input of DDT into mariculture area of Zhelin Bay, and at the other sites the sources of DDT were from the early residue in sediments or the long-term weathering sediments of using pesticides. There was a very significant positive correlation between HCHs, endosulfan, chlordane and dieldrin in sediments, while there was a negative relation between the above OCPs and TOC, which indicated that the presence of TOC could promote their biodegradation. There was a significant positive correlation between p, p'-DDD and Ca, which revealed that DDT used in the early period was deposited with biological carbonate. Increasing size of sediment particles discouraged the accumulation and enrichment of OCPs in sediments.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Praguicidas/análise , Poluentes Químicos da Água/análise , Baías , China , DDT , Hidrocarbonetos Clorados , Medição de Risco
15.
Huan Jing Ke Xue ; 36(9): 3447-56, 2015 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-26717709

RESUMO

This study aimed to investigate the pollution degree and human health risk of heavy metals in soil and air samples around electroplating factories. Soil, air and waste gas samples were collected to measure 8 heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) in two electroplating factories, located in Baiyun district of Guangzhou city. Geoaccumulation index and USEPA Risk Assessment Guidance for Superfund (RAGS) were respectively carried out. Results showed that concentrations of Hg and Pb in waste gas and Cr in air samples were higher than limits of the corresponding quality standards, and concentrations of Cd, Hg and Zn in soil samples reached the moderate pollution level. The HQ and HI of exposure by heavy metals in air and soil samples were both lower than 1, indicating that there was no non-carcinogen risk. CRAs and CRCr in soil samples were beyond the maximum acceptable level of carcinogen risk (10(-4)), and the contribution rate of CRCr to TCR was over 81%. CRCr, CRNi and TCR in air samples were in range of 10(-6) - 10(-4), indicating there was possibly carcinogen risk but was acceptable risk. CR values for children were higher than adults in soils, but were higher for adults in air samples. Correlation analysis revealed that concentrations of heavy metals in soils were significantly correlated with these in waste gas samples, and PCA data showed pollution sources of Cd, Hg and Zn in soils were different from other metals.


Assuntos
Poluentes Atmosféricos/análise , Galvanoplastia , Monitoramento Ambiental , Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Poluição Ambiental , Humanos , Medição de Risco
16.
Bull Math Biol ; 76(2): 476-85, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24500062

RESUMO

Game-theoretic models predict that there is an ESS height for the plant population to which all individual plants should converge. To attain this conclusion, the neighborhood factors were assumed to be equal for all the individual plants, and the spatial pattern and size variation of population were left without consideration, which is clearly not right for the scenario of plant competition. We constructed a spatially-explicit, individual-based model to explore the impacts of spatial structure and size variation on individual plant's height and population's height hierarchies under the light competition. The monomorphic equilibrium of height that all the individual plants will converge to only exists for a population growing in a strictly uniform spatial pattern with no size variation. When the spatial pattern of the population is non-uniform or there's size variation among individual plants, the critical heights that individual plants will finally reach are different from each other, and the height inequality at the end of population growth will increase when the population's spatial pattern's degree of deviation from uniform and population's size variation increase. Our results argue strongly for the importance of spatial pattern and neighborhood effects in generating the diversity of population's height growth pattern.


Assuntos
Modelos Biológicos , Desenvolvimento Vegetal , Plantas/anatomia & histologia , Evolução Biológica , Ecossistema , Teoria dos Jogos , Conceitos Matemáticos , Processos Fototróficos , Árvores/anatomia & histologia , Árvores/crescimento & desenvolvimento
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