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1.
An Acad Bras Cienc ; 91(4): e20180666, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31644642

RESUMO

Here we model and describe the wood volume of Cerrado Sensu Stricto, a highly heterogeneous vegetation type in the Savanna biome, in the state of Minas Gerais, Brazil, integrating forest inventory data with spatial-environmental variables, multivariate regression, and regression kriging. Our study contributes to a better understanding of the factors that affect the spatial distribution of the wood volume of this vegetation type as well as allowing better representation of the spatial heterogeneity of this biome. Wood volume estimates were obtained through regression models using different environmental variables as independent variables. Using the best fitted model, spatial analysis of the residuals was carried out by selecting a semivariogram model for generating an ordinary kriging map, which in turn was used with the fitted regression model in the regression kriging technique. Seasonality of both temperature and precipitation, along with the density of deforestation, explained the variations of wood volume throughout Minas Gerais. The spatial distribution of predicted wood volume of Cerrado Sensu Stricto in Minas Gerais revealed the high variability of this variable (15.32 to 98.38 m3 ha-1) and the decreasing gradient in the southeast-northwest direction.


Assuntos
Biomassa , Florestas , Madeira , Brasil , Geografia , Análise Espacial
2.
Zhonghua Liu Xing Bing Xue Za Zhi ; 40(10): 1262-1268, 2019 Oct 10.
Artigo em Chinês | MEDLINE | ID: mdl-31658528

RESUMO

Objective: To evaluate the burden and to describe the characteristics of spatial distribution caused by malignant tumors among different administrative areas in Guangzhou from 2010- 2013. Methods: Based on data from the Cancer Registry system and population in Guangzhou in 2010- 2013, disability-adjusted life year (DALY) was assessed on the disease burden of cancer, in accordance with the method used in the Global Burden of Disease study. Results: The crude incidence rates of cancer appeared as 256.22/10(5) in 2010-2011 and 270.04/10(5) in 2012-2013, with the crude mortality rates as 143.17/10(5) and 148.01/10(5), respectively, in Guangzhou. Cancers caused 606 238.95 DALYs in 2010-2011 and 623 763.80 DALYs in 2012-2013 for both sexes and 37.63 and 37.81 person year per 1 000 persons, with the standardized DALY rates as 34.51‰, 34.00‰ respectively. Three administrative districts (Yuexiu, Haizhu and Liwan) were with the largest disease burden of cancers that accounted for 45% of the DALYs for the whole Conghua district, with liver cancer was the leading cancer on DALYs, and tracheal, bronchus and lung cancer ranked the first in the other districts. Conclusions: In Guangzhou, disease burden caused by cancers was both prominently seen in the newly developed urban area and the old districts. It remains an arduous task to continue programs on control and prevention of cancers in this city.


Assuntos
Neoplasias/epidemiologia , China/epidemiologia , Efeitos Psicossociais da Doença , Feminino , Humanos , Masculino , Anos de Vida Ajustados por Qualidade de Vida , Sistema de Registros , Comportamento Sexual , Análise Espacial
3.
Zhonghua Liu Xing Bing Xue Za Zhi ; 40(9): 1099-1105, 2019 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-31594153

RESUMO

Objective: To analyze the spatial distribution and both hot and cold spots of incidence on Brucellosis in Gansu province from 2013 to 2018. Methods: Based on data from the Infectious Disease Reporting Information System in China, data related to space-time distribution and both hot and cold spots of Brucellosis in Gansu province from 2013 to 2018 were analyzed, by using the ArcGIS 10.5 software and GeoDa 1.6 software. Results: The trend surface analysis showed that the incidence of Brucellosis decreased gradually from the northern to southern parts with slightly higher in the west than in the east of Gansu. Global spatial autocorrelation analysis showed that the Moran's I of Brucellosis in Gansu province from 2013 to 2018 were 0.242, 0.487, 0.424, 0.460, 0.427 and 0.468 (P<0.01), suggesting that the incidence of Brucellosis had spatial clustering features in Gansu province. Local global spatial autocorrelation analysis showed that the number of hot spots were declining in the eastern and north-central regions while the hot spots were increasing in the Hexi area (Wuwei, Zhangye, Jinchang and Jiuquan cities). The cold spots areas were mainly seen in the eastern, southeastern and south of central regions in Gansu province. Conclusions: The incidence of Brucellosis showed obviously spatial clustering characteristics in Gansu province. The number of hot spots were decreasing in the eastern and north of central regions while the hot spots were increasing in the Hexi area, suggesting that the prevention and control measures for Brucellosis should be further strengthened in these areas.


Assuntos
Brucelose/epidemiologia , China/epidemiologia , Cidades , Análise por Conglomerados , Humanos , Análise Espacial , Análise Espaço-Temporal
4.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 31(4): 368-373, 2019 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-31612670

RESUMO

OBJECTIVE: To develop a method for designing schistosomiasis surveillance sites, so as to improve the efficiency and quality of schitsosomiasis surveillance. METHODS: By using the minimum spanning tree-based Spatial Kluster Analysis by Tree Edge Removal (SKATER) method, spatially constrained clustering was performed upon 31 historical schistosomiasis-endemic counties (districts) in Anhui Province. A surveillance site was selected from each cluster to evaluate the representativeness and surveillance efficiency of these cluster-based surveillance sites for the endemic situation of schistosomiassi in Anhui Province, and to compare the surveillance efficiency with local national schistosomiasis surveillance sites. RESULTS: There was no significant difference in the environmental factors between the cluster-based schistosomiasis surveillance sites and the whole region, showing a high homogeneity. If the same number of schistosomiasis surveillance sites was selected, there was no significant difference between the cluster-based surveillance sites and national schistosomiasis surveillance sites in the efficiency of the mean risk and long-term trend of schistosomiasis surveillance in Anhui Province; however, the cluster-based surveillance sites were superior to the national schistosomiasis surveillance sites for the prediction and estimation of the endemic situation of schistosomiasis in the unmonitored areas. CONCLUSIONS: The SKATER-based selection of schistosomiasis surveillance sites may better represent the endemic situation of schistosomiasis in Anhui Province, which may serve as an effective supplement for the conventional method of selecting schistosomiasis surveillance sites.


Assuntos
Métodos Epidemiológicos , Vigilância da População , Esquistossomose , Caramujos , Animais , China/epidemiologia , Análise por Conglomerados , Humanos , Vigilância da População/métodos , Schistosoma/fisiologia , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , Caramujos/parasitologia , Análise Espacial
5.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 31(4): 374-381, 2019 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-31612671

RESUMO

OBJECTIVE: To investigate the spatial distribution of Oncomelania hupensis snail habitats at the administrative village scale in schistosomiasis-endemic areas of Hubei Province, so as to provide scientific bases for precise control of O. hupensis snails in the province. METHODS: Data regarding snail distribution at the village level in Hubei Province in 2017 were collected to create a spatial analysis database of snail distribution in Hubei Province. The spatial aggregations of O. hupensis distribution were analyzed using Moran's I index and Local Moran's I index. In addition, the distances from schistosomiasis-endemic villages to the Yangtze River were captured using the software ArcGIS 13.0, and their correlations with area of snail habitats were examined with the Spearman correlation method. RESULTS: O. hupensis snails were mainly distributed in 5 450 endemic villages from 63 counties of 13 cities in Hubei Province in 2017. The global spatial autocorrelation analysis showed spatial aggregations in the areas of historically accumulated snail habitats, current areas of snail habitats, areas of snail habitats outside the embankment and snail habitats inside the embankment (all Z Scores > 0, all P values < 0.05), and no spatial aggregation was seen in the areas of snail habitats in hilly areas (Z Score > 0, P > 0.05). There were four types of spatial distribution of historically accumulated areas of snail habitats, areas of current snail habitats, areas of snail habitats outside the embankment and snail habitats inside the embankment, including the high-high type (H-H type), high-low type (H-L type), low-high type (L-H type) and random distribution type, and a high percentage of the H-H type was found. There were 340, 125 and 110 endemic villages with the H-H type of areas of historically accumulated snail habitats, current areas of snail habitats and areas of snail habitats outside the embankment, and these villages were mainly concentrated in Wuhan and Jingzhou cities, with almost consistent spatial aggregation locations. There were 319 endemic villages with the H-H type of distribution of snail habitats inside the embankment, which were mainly distributed in Jingzhou, Xiaogan and Huangshi cities. In addition, the areas of historically accumulated snail habitats, current areas of snail habitats and areas of snail habitats outside the embankment negatively correlated with the distance from the endemic villages to the Yangtze River (r = -0.094, P < 0.01; r = -0.225, P < 0.01; r = -0.177, P < 0.01). CONCLUSIONS: The clustering areas of snail habitats along the Yangtze River Basin, notably the villages near the Yangtze River are key regions for snail monitoring and control in Hubei Province.


Assuntos
Distribuição Animal , Rios , Esquistossomose , Caramujos , Animais , China/epidemiologia , Ecossistema , Humanos , Rios/parasitologia , Schistosoma/fisiologia , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , Esquistossomose/transmissão , Caramujos/parasitologia , Caramujos/fisiologia , Análise Espacial
6.
Ying Yong Sheng Tai Xue Bao ; 30(10): 3419-3425, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31621228

RESUMO

In this study, data of 19 climatic factors were downloaded from the World Climate website. A total of 233 Cymbidium kanran distribution data were obtained through online review and field visits. Using MaxEnt model and combined with ArcGIS spatial analysis technology, the potential distribution area and distribution pattern of C. kanran in different periods were simulated, as well as its distribution during the last glacial period and 2070. The results showed that the curve indexes (AUC) value of the model training set was 0.957, and the AUC value of the verification set was 0.953, indicating that the prediction accuracy of the model was very high. The current distribution of C. kanran was mostly affected by the driest quarter precipitation, mean annual precipitation, wettest quarter precipitation, and mean annual temperature range. The contribution rates were 50.3%, 15.9%, 8.4% and 4.4%, respectively, with the total contribution rate being 79.0%. In the last glacial period, C. kanran mainly distributed in Wuyi Mountain, Luojing Mountain, Nanling, Taiwan's five major mountains and some hills in the northern part of Guangxi. From now to 2070, the distribution of C. kanran area will decrease by 22.4%. The southwestern part of Guangxi, the central part of Yunnan, and the junctions of Jiangxi, Fujian and Guangdong provinces will expand, while that in eastern Jiangxi, western Fujian, and the border between these two provinces will shrink.


Assuntos
Mudança Climática , China , Análise Espacial , Taiwan
7.
Zhongguo Zhong Yao Za Zhi ; 44(14): 2987-2995, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31602844

RESUMO

The study aims to investigate spatial distribution pattern and age structure of wild Angelica sinensis in Gansu province.Ten plots each with an area of 100 m2 were set and the spatial coordinates of all wild A. sinensis individuals were measured within each plot. Based on plant individual mapping data,we explored the spatial distribution pattern and its differences between different life history stages of wild A. sinensis in Gansu province by using nearest neighbor distance statistics. Correlation analysis were carried out to explore the relationship between spatial aggregation degree and topographic factors. We also distinguished individuals to three life history stages( i.e. seedlings,adults and boltings) and then test the differences among/between them using nonparametric test.(1)We found that the dominant spatial distribution pattern of wild A. sinensis population in Gansu was aggregated distribution. There was no significant correlation between spatial aggregation degree of wild A. sinensis and altitude,slope and aspect. There was no significant difference between the average distance from seedlings to their nearest bolting individuals; the average distance from adult individuals to their nearest seedlings was significantly larger than the average distance from adult individuals to their nearest adult individuals; and the average distance from bolting individuals to their nearest adult individuals was significantly smaller than the average distance from bolting individuals to their nearest bolting individuals.(2)The age structure was showed as a declining population,characterized by less seedlings and bolting individuals,while more adult individuals within population. The population characteristics of wild A. sinensis,characterized by aggregated distribution pattern and senescent type of age structure,are disadvantage to its population development. The factors,such as habitat specialization,human activities and intraspecific competition,which shapes the current population characteristics,may increase the threatened status of wild A. sinensis. We suggest to strengthen the protection of wild A. sinensis.


Assuntos
Angelica sinensis/crescimento & desenvolvimento , Ecossistema , Altitude , China , Conservação dos Recursos Naturais , Plântula , Análise Espacial
8.
Ying Yong Sheng Tai Xue Bao ; 30(9): 3046-3056, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31529880

RESUMO

This study evaluated the changes of spatial distribution of the constructive species Stipa breviflora in the desert steppe under different grazing intensities (control, light, moderate, and heavy grazing) in Siziwang, Inner Mongolia. The small-scale spatial distribution of S. breviflora was measured. Results showed that population density of S. breviflora was following the order: heavy grazing (27.81 individuals·m-2) > moderate grazing (22.17 individuals·m-2) > control (11.31 individuals·m-2) > light grazing (10.76 individuals·m-2). The moderate and heavy grazing significantly increased population density of S. breviflora. According to the model fitting by semi-variance function, the population density of S. breviflora under the control, light, moderate and heavy gra-zing treatments were consistent with the exponential model, spherical model, exponential model and spherical model, respectively. Results from spatial distribution pattern analysis showed that structural ratio of S. breviflora population was control (99.7%) > heavy grazing (94.7%) > light grazing (92.7%) > moderate grazing (87.9%). Such a result indicated that the spatial autocorrelation of the four treatments was high, which were mainly affected by structural factors. In comparison, S. breviflora population structure ratio under moderate grazing treatment was the smallest, and partly affected by random factors. Based on fractal dimension analysis, spatial structure of the four treatments was good with simple spatial distribution. With the increases of grazing intensity, the spatial distribution was simpler and more homogeneous. Combined with 2D and 3D views, both light and heavy grazing changed spatial distribution of S. breviflora population from gradient distribution to patch distribution and resulted in the reduction of spatial heterogeneity.


Assuntos
Ecossistema , Meio Ambiente , Herbivoria , Poaceae/fisiologia , China , Análise Espacial
9.
Zhonghua Liu Xing Bing Xue Za Zhi ; 40(8): 930-935, 2019 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-31484256

RESUMO

Objective: To explore the spatial-temporal distribution and epidemic characteristics of hemorrhagic fever with renal syndrome (HFRS) in Hebei province from 2005 to 2016. Methods: Records of HFRS cases reported from each county in Hebei during January 2005 to December 2016 were collected from National Notifiable Disease Surveillance System (NNDSS). Global and local spatial association statistics were used to measure the spatial autocorrelation and software GeoDa 1.2.0. Software SaTScan 9.4.1 was used to analyze spatiotemporal clusters. Software ArcGIS 10.2 was used to visualize the yearly scan results. Results: In Hebei province, a total of 8 437 human HFRS cases reported from 170 counties with an annual incidence rate of 0.99/100 000 population during 2005-2016. The peak incidence season was spring. Global spatial autocorrelation analysis on the incidence of HFRS at county-level showed that the value of Moran's I were all above 0 (P<0.05), indicating that the significant spatial cluster. The result of local indicators on spatial association (LISA) analysis revealed that identified hot spots were mainly in northeastern area, while cold spots were found in some counties of central and southern areas. Spatial-temporal scan detected that the primary cluster of HFRS incidence was mainly distributed in Qinhuangdao city and Tangshan city, including 11 counties (city/district): Beidaihe district, Haigang district, Funing district, Shanhaiguan district, Changli county, Lulong county and Qinglong Manchu autonomous county in Qinhuangdao city, and Qian'an city, Laoting county, Luanzhou city and Luannan county in Tangshan city (RR=39.64, P<0.001), during January-July in 2005. Conclusions: There were significant spatial-temporal cluster of HFRS in Hebei from 2005 to 2016. The cluster areas of HFRS were mainly in northeastern Hebei, it is necessary to strengthen the prevention and control programs of HFRS in these areas.


Assuntos
Notificação de Doenças/estatística & dados numéricos , Vírus Hantaan , Febre Hemorrágica com Síndrome Renal/epidemiologia , Vigilância da População , China/epidemiologia , Cidades , Análise por Conglomerados , Humanos , Incidência , Estações do Ano , Análise Espacial , Análise Espaço-Temporal
10.
Zhonghua Liu Xing Bing Xue Za Zhi ; 40(8): 947-952, 2019 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-31484259

RESUMO

Objective: To analyze the epidemiological and spatial-temporal distribution of Brucellosis, epidemic encephalitis B and hemorrhagic fever with renal syndrome (HFRS) in Gansu province during 2014-2018 so as to provide evidence for the prevention and control of those diseases. Methods: A database was established in Gansu province from 2014 to 2018, using the geographical information system. A spatial distribution map was drawn, with trend analysis and space-time clustering used to study the 3-dimention of the diseases, by using both ArcGIS 10.5 and SaTScan 9.6 softwares. Results: Results from the trend surface analysis showed that the incidence of Brucellosis decreased gradually from north to south parts while the U type curve could reflect the distribution from the east to the west areas. Incidence of epidemic encephalitis B decreased significantly from south to north areas in the province, with incidence higher in the eastern than in the mid-west region. Difference on the incidence of HFRS was not significantly visible in the eastern and western regions, while the incidence was slightly higher in the southern than the northern parts of the province. Spatial and space-time clustering did exist among the 3 diseases in Gansu from 2014 to 2018. The areas with clusters of Brucellosis appeared in the eastern parts during 2014-2015, including 19 counties. The areas with secondary clusters of Brucellosis were seen in the Hexi district, including 4 counties, during 2017-2018. The areas with high incidence of epidemic encephalitis B were clustered in the middle and southeast areas, including 32 counties, during 2017-2018. Areas with most clusters of HFRS appeared in Min county of Dingxi city in 2018, with the areas of secondary clusters in 8 counties of the eastern areas in 2018. Conclusions: The overall incidence rates of the 3 natural focus diseases were in a upward trend and showing obvious characteristics on spatial clustering. According to the distributive characteristics, effective measures should be developed accordingly.


Assuntos
Brucelose/epidemiologia , Notificação de Doenças/estatística & dados numéricos , Encefalite por Arbovirus/epidemiologia , Febre Hemorrágica com Síndrome Renal/epidemiologia , China/epidemiologia , Cidades , Análise por Conglomerados , Monitoramento Epidemiológico , Humanos , Incidência , Conglomerados Espaço-Temporais , Análise Espacial , Análise Espaço-Temporal
11.
J Environ Radioact ; 208-209: 106044, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31521882

RESUMO

This paper presents a geostatistical simulation approach to not only map the county-level indoor radon concentration (IRC) distributions in South Korea, but also quantify the uncertainty that can be used as decision-supporting information. For county-level IRC mapping in South Korea, environmental factors including geology, radium concentration in surface soil, gravel content in subsoil, and fault line density, which are known to be associated with the source and migration of radon gas, were incorporated into IRC measurements using multi-Gaussian kriging with local means. These four environmental factors could account for about 36% of the variability of noise-filtered IRCs, implying that regional variations of IRCs were affected by these factors. Sequential Gaussian simulation was then applied to generate alternative realizations of county-level IRC distributions. By summarizing the multiple simulation results, we identified some counties that lay on the great limestone series showed elevated IRCs. In addition, there were some counties in which the proportion of grids exceeding the recommended level was high but the uncertainty was also large according to the analysis of several uncertainty measures, which indicates that additional sampling is required for these counties. From the local cluster analysis in conjunction with simulation results, we found that the counties with higher levels of IRC belonged to the statistically significant clusters of high values, and these counties should be the prime targets for radon management and in-depth survey. The geographical distributions of IRC and uncertainty measures presented in this study provide guidance for effective radon management if they are consistently combined with both future IRC measurements and a geogenic radon potential map.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Monitoramento de Radiação , Radônio/análise , Poluição do Ar em Ambientes Fechados/análise , Contaminação Radioativa do Ar/estatística & dados numéricos , Análise por Conglomerados , República da Coreia , Análise Espacial
12.
Environ Monit Assess ; 191(9): 554, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399761

RESUMO

A proper evaluation and performance assessment of climate model projections have received considerable attention during the recent past amongst the scientific community. Quality of wind datasets used for analysis is of paramount importance to meteorologists, oceanographers, and climatologist as an essential pre-requisite for modelling needs. This study examined the measured wind speeds obtained from satellite altimetry available from IFREMER/CERSAT, along with two atmospheric reanalysis products ECMWF ERA-Interim and NCEP-CFSR. The reanalysis products and altimeter data were compared with wind speed simulated from 33 different models under WCRP-CMIP5 project for the Bay of Bengal (BoB) region. Study investigated both historical and projections of CMIP5 data providing an opportunity to inter-compare the wind speeds resulting from various emission scenarios with Representative Concentration Pathways (RCPs) 2.6, 4.5, 6.0, and 8.5, respectively. The objective is to establish and find out a suitable emission scenario applicable to the BoB region. Temporal and spatial analyses of CMIP5 data infer variability in terms of correlation, bias, and root mean square error. For the historical runs (1991-2005) based on analysis of 29 CMIP5 models, it could be ascertained that the correlation coefficient in wind speed varied between 0.6 and 0.9 and with a bias ranging from - 1.6 to 4 ms-1. Similar analysis of the CMIP5 projections was carried out with 11 models for RCP 2.6, 29 models for RCP 4.5, 10 models for RCP 6.0, and 28 models for RCP 8.5. Basin-scale mean using altimeter and re-analysis products indicates that RCPs 2.6 and 6.0 showed less correlation with a higher bias for the study region. Analysis of historical model runs signifies that HadGEM2-ES, HadGEM2-AO, HadGEM2-CC, MIROC5, GISS-E2R, and CNRM-CM5 are the best performing models for the study domain. Findings from the study indicate that RCP 4.5 wind speed stands better for the Bay of Bengal region. In a broader perspective, due to various uncertainties involved in climate model outputs, it is imperative to perform a comprehensive analysis amongst multiple data sources to establish and identify the best quality data for scientific needs.


Assuntos
Mudança Climática/estatística & dados numéricos , Monitoramento Ambiental/métodos , Vento , Baías , Clima , Previsões , Análise Espacial
13.
An Acad Bras Cienc ; 91(3): e20180334, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31411254

RESUMO

The aim of this study is to discuss the concentration distribution, composition and possible sources of trace metals and 13 PAHs in topsoils of the University campus, in the city of São Paulo, the largest city of South America. Mineralogy and granulometry of topsoils (0-10 cm) samples, were determined and As, Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, Sb, V, Zn, Hg, Pt, Pd and PAHs concentrations were quantified in the bulk fraction. The average clay content of soils was 221±61.8 g kg-1 and total carbon was low (mean of 25 g kg-1). Concentrations of metals were generally lower than the reference value established by the São Paulo State Environmental Agency and other studies in the São Paulo urban area, except for Cd, Ni, Pb, Cr and Zn. The mean concentration of the sum of 13 PAHs was 0.33 mg kg-1 and fluorene, indeno(1,2,3-cd)pyrene, anthracene, pyrene and benzo(ghi)perylene were the most abundant compounds. PAHs and trace metals variability were constrained in PMF analysis and showed an association with exhaust and non-exhaust vehicular emissions. The results also pointed out a spatial pattern in the campus area related to traffic conditions and intensity and terrain slope.


Assuntos
Metais Pesados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Solo/química , Oligoelementos/análise , Universidades , Brasil , Cidades , Monitoramento Ambiental , Humanos , Metais Pesados/química , Hidrocarbonetos Policíclicos Aromáticos/química , Medição de Risco , Análise Espacial , Oligoelementos/química , Poluição Relacionada com o Tráfego/análise , Emissões de Veículos/análise
14.
Environ Pollut ; 252(Pt B): 1719-1729, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31284214

RESUMO

Microplastic pollution within the marine environment is of pressing concern globally. Accordingly, spatial monitoring of microplastic concentrations, composition and size distribution may help to identify sources and entry pathways, and hence allow initiating focused mitigation. Spatial distribution patterns of microplastics were investigated in two compartments of the southern North Sea by collecting sublittoral sediment and surface water samples from 24 stations. Large microplastics (500-5000 µm) were detected visually and identified using attenuated total reflection (ATR) Fourier transform infrared (FTIR) spectroscopy. The remaining sample was digested enzymatically, concentrated onto filters and analyzed for small microplastics (11-500 µm) using Focal Plane Array (FPA) FTIR imaging. Microplastics were detected in all samples with concentrations ranging between 2.8 and 1188.8 particles kg-1 for sediments and 0.1-245.4 particles m-3 for surface waters. On average 98% of microplastics were <100 µm in sediments and 86% in surface waters. The most prevalent polymer types in both compartments were polypropylene, acrylates/polyurethane/varnish, and polyamide. However, polymer composition differed significantly between sediment and surface water samples as well as between the Frisian Islands and the English Channel sites. These results show that microplastics are not evenly distributed, in neither location nor size, which is illuminating regarding the development of monitoring protocols.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Plásticos/análise , Poluentes Químicos da Água/análise , Mar do Norte , Polipropilenos/análise , Poliuretanos/análise , Água do Mar/química , Análise Espacial
15.
Accid Anal Prev ; 131: 157-170, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31277019

RESUMO

Animal-vehicle collisions (AVCs) are a growing problem in the United States, resulting in countless loss of animal life and considerable human injury and death every year, especially to motorcyclists. Due to underreporting, collision data generally provide a very low (highly biased) estimate of actual AVC counts and often lack key details, such as the species of animals involved. However, AVC reports cover entire states and nations, and can illuminate differences in wild versus domestic animal-vehicle collisions through statistical and spatial analysis. 51,522 animal-related crashes were reported to Texas police from 2010 through 2016, at a total cost over $1.3 billion annually to Texas motorists - not including the value of lost animal lives. AVC reports jump twice a day: between 5 and 8 AM and between 5 and 10 PM. Motorists are also significantly more likely to collide with a wild animal during the months of October, November, and December. Wildlife-vehicle collisions (WVC) are 64% of total reports, events involving domestic animals (like dogs and cattle) are 31%, and the remaining 5% of reports are unspecified. Most AVCs in the state occur at night in unlit locations, usually on rural roads with very low traffic volumes. Using ordinary least-squares (OLS) regression analysis across Texas' n = 254 counties, this work finds that less densely populated counties, marked as rural, and those with fewer vehicle-miles traveled (VMT) per capita but more lane-miles per capita, tend to experience the greatest number of AVCs per VMT, after controlling for county average rainfall, share of VMT onsystem roadways, job densities, and vehicle ownership (vehicles per capita). Intervention options for the mitigation of animal-vehicle collisions are numerous and diverse. For wildlife collisions specifically, this work finds that large crossing structures (underpasses and overpasses) at the highway link level return benefit-to-cost ratios near 3.0, while their lower-cost counterparts (wildlife fencing and animal detection systems) deliver ratios up to 30.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Animais Domésticos , Animais Selvagens , Acidentes de Trânsito/economia , Acidentes de Trânsito/prevenção & controle , Animais , Ambiente Construído , Bovinos , Cães , Humanos , População Rural , Análise Espacial , Texas , Estados Unidos
16.
BMC Public Health ; 19(1): 914, 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31288765

RESUMO

BACKGROUND: The first Canadian outbreak of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) was identified in 2004 in Calgary, Alberta. Using a novel model of MRSA population-based surveillance, sociodemographic risk associations, yearly geospatial dissemination and prevalence of CA-MRSA infections over an 11 year period was identified in an urban healthcare jurisdiction of Calgary. METHODS: Positive MRSA case records, patient demographics and laboratory data were obtained from a centralized Laboratory Information System of Calgary Laboratory Services in Calgary, Alberta, Canada between 2004 and 2014. Public census data was obtained from Statistics Canada, which was used to match with laboratory data and mapped using Geographic Information Systems. RESULTS: During the study period, 52.5% of positive MRSA infections in Calgary were CA-MRSA cases. The majority were CMRSA10 (USA300) clones (94.1%; n = 4255), while the remaining case (n = 266) were CMRSA7 (USA400) clones. Period prevalence of CMRSA10 increased from 3.6 cases/100000 population in 2004, to 41.3 cases/100000 population in 2014. Geospatial analysis demonstrated wide dissemination of CMRSA10 annually in the city. Those who are English speaking (RR = 0.05, p <  0.0001), identify as visible minority Chinese (RR = 0.09, p = 0.0023) or visible minority South Asian (RR = 0.25, p = 0.015), and have a high median household income (RR = 0.27, p <  0.0001) have a significantly decreased relative risk of CMRSA10 infections. CONCLUSIONS: CMRSA10 prevalence increased between 2004 and 2007, followed by a stabilization of cases by 2014. Certain sociodemographic factors were protective from CMRSA10 infections. The model of MRSA population-surveillance and geomap outbreak events can be used to track the epidemiology of MRSA in any jurisdiction.


Assuntos
Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/microbiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Vigilância da População , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Adulto , Alberta/epidemiologia , Feminino , Sistemas de Informação Geográfica , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Análise Espacial
17.
Accid Anal Prev ; 131: 297-307, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31351232

RESUMO

Maintaining taxi safety is one of the important goals of operating urban transportation systems. Taxicabs are often prone to higher crash risk due to their long-time exposure to the complicated and dynamic traffic environments in urban areas. Despite existing efforts in understanding the safety issues associated with these vehicles, there were still few attempts that have specifically examined the relationship between taxi-involved crashes and other multifaceted contributing factors. To this end, this paper aims to develop crash frequency models for analyzing taxi-involved crashes. In particular, the spatial autocorrelations between variables were explored and the Poisson conditional autoregressive (Poisson-CAR) models for taxi-involved crashes were proposed. Unlike previous safety studies that mainly consider distance as the key indicator of spatial correlation, the present paper introduced the use of massive taxi trip data for constructing a more informative spatial weight matrix. The developed models with the taxi trip-based weight matrix were tested by using the 2016 taxi trip data collected in Washington D.C. The modeling results highlight the key explanatory factors such as road density, taxi activity, number of bus stops, and land use. More importantly, it demonstrates that the proposed Poisson-CAR models with the taxi trip-based weight matrix outperformed both the non-spatial Poisson model and the Poisson-CAR models using conventional distance-based weight matrix. Moran's I tests further indicate that our proposed models have sufficiently accounted for the spatial autocorrelation of the residuals. Thus, it deserves to consider informative spatial weight matrices when applying spatial models in traffic safety studies.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Automóveis/estatística & dados numéricos , District of Columbia , Humanos , Segurança , Análise Espacial
18.
Parasit Vectors ; 12(1): 352, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31311596

RESUMO

BACKGROUND: Taenia solium (cysticercosis) is a parasitic cestode that is endemic in rural populations where open defecation is common and free-roaming pigs have access to human feces. The purpose of this study was to examine the roaming patterns of free-range pigs, and identify areas where T. solium transmission could occur via contact with human feces. We did this by using GPS trackers to log the movement of 108 pigs in three villages of northern Peru. Pigs were tracked for approximately six days each and tracking was repeated in the rainy and dry seasons. Maps of pig ranges were analyzed for size, distance from home, land type and contact with human defecation sites, which were assessed in a community-wide defecation survey. RESULTS: Consistent with prior GPS studies and spatial analyses, we found that the majority of pigs remained close to home during the tracking period and had contact with human feces in their home areas: pigs spent a median of 79% (IQR: 61-90%) of their active roaming time within 50 m of their homes and a median of 60% of their contact with open defecation within 100 m of home. Extended away-from-home roaming was predominately observed during the rainy season; overall, home range areas were 61% larger during the rainy season compared to the dry season (95% CI: 41-73%). Both home range size and contact with open defecation sites showed substantial variation between villages, and contact with open defecation sites was more frequent among pigs with larger home ranges and pigs living in higher density areas of their village. CONCLUSIONS: Our study builds upon prior work showing that pigs predominately roam and have contact with human feces within 50-100 m of the home, and that T. solium transmission is most likely to occur in these concentrated areas of contact. This finding, therefore, supports control strategies that target treatment resources to these areas of increased transmission. Our finding of a seasonal trend in roaming ranges may be useful for control programs relying on pig interventions, and in the field of transmission modeling, which require precise estimates of pig behavior and risk.


Assuntos
Cisticercose/veterinária , Defecação , Fezes/parasitologia , Estações do Ano , Doenças dos Suínos/transmissão , Animais , Comportamento Animal , Cisticercose/epidemiologia , Cisticercose/transmissão , Feminino , Sistemas de Informação Geográfica , Humanos , Masculino , Movimento , Peru/epidemiologia , Fatores de Risco , População Rural , Análise Espacial , Suínos/parasitologia , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/parasitologia , Taenia solium/isolamento & purificação
19.
Environ Monit Assess ; 191(8): 484, 2019 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-31280377

RESUMO

Epidemiological research requires accurate prediction of the concentrations of air pollutants. In this study, satellite-based estimates (OMI NO2), distance-weighted models (DWMs), and universal kriging (UK) are applied to land use regression (LUR) to predict annually and monthly averaged NO2 concentrations in the continental United States. In addition, to assess environmental risk, the relationship between NO2 concentrations and people potentially exposed to NO2 within urban areas is explored in 377 metropolitan statistical areas (MSAs). The results of this study show that the application of a combination of OMI NO2, UK, and DWMs to LUR yielded the highest cross-validated (CV) R2 values and the lowest root mean square error of prediction (RMSEP): 82.9% and 0.392 on a square root scale of ppb in the annual model and 70.4-83.5% and 0.408-0.518 on square root scale of ppb in the monthly models, respectively. Moreover, the model presented a spatially unbiased distribution of CV error terms. Models based on LUR provided more accurate NO2 predictions with lower RMSEP in urban areas than in rural areas. In addition, this study finds that the people living in the urban areas of MSAs, with larger populations and a higher percentage of children under 18 years of age, are likely to be exposed to higher NO2 concentrations. By contrast, people living in the urban areas of MSAs with a higher percentage of the elderly over 65 years of age are likely to be exposed to lower NO2 concentrations.


Assuntos
Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Dióxido de Nitrogênio/análise , Adolescente , Idoso , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Criança , Pré-Escolar , Monitoramento Ambiental/métodos , Humanos , Análise Espacial , Estados Unidos
20.
Environ Monit Assess ; 191(8): 492, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300895

RESUMO

Irrigation water salinity is one of the factors that reduces agricultural production. Guilan Province is one of the most important rice-producing areas in Iran where groundwater is used for irrigation. The temporal and spatial variations of groundwater salinity were studied in the coastal strip covering 4285 km2 of the province using data from 73 wells, as well as its estimated effect on the rice yield. Data on mean electrical conductivity (EC) for each 6-month period of 12 consecutive years, from the second half of 2002 until the end of 2014, were analyzed and resulted in 25 mean ECs. EC maps and maps of the probability of higher salinity areas were obtained by using ordinary kriging (OK) and indicator kriging (IK) in ArcGIS 9.3 software, respectively. Thereby, areas belonging to different salinity classes were outlined and places with higher salinity reducing the rice yield were identified. In addition, the Mann-Kendall test and Sen's slope were used to project future changes. The results indicated that due to the salinity of groundwater in the coastal strip area, the minimum and the maximum rice yields were 80% and 100%, respectively. Using the IK method, higher probability of groundwater salinity reducing the yield was found from the central parts toward the east. The Mann-Kendal test result showed significant temporal trends of the size of areas below the 100% yield (EC < 1 dS/m) and 90-100% yield (1 < EC < 1.34 dS/m) thresholds. The equations given by Sen's slope estimator indicated that the groundwater salinity will not be a limiting factor for achieving 100% rice yields from the year of 2021 onward in all of the Guilan coastal area. The trend of increasing precipitation in the area may be an important cause.


Assuntos
Irrigação Agrícola/métodos , Produtos Agrícolas/crescimento & desenvolvimento , Grão Comestível/crescimento & desenvolvimento , Monitoramento Ambiental/métodos , Água Subterrânea/química , Oryza/crescimento & desenvolvimento , Irrigação Agrícola/tendências , Previsões , Irã (Geográfico) , Salinidade , Análise Espacial
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