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1.
Shanghai Journal of Preventive Medicine ; (12): 857-862, 2023.
Article in Chinese | WPRIM | ID: wpr-998189

ABSTRACT

ObjectiveTo analyze the monitoring data of schistosomiasis from 2004 to 2021 in Suzhou New District, Jiangsu Province, and to provide evidence for improving schistosomiasis elimination strategies. MethodsFollowing the Opinions on Prevention and Control of Schistosomiasis, Parasitic Diseases and Endemic Diseases in Suzhou and the Technical Plan for Prevention and Control of Schistosomiasis, Parasitic Diseases and Endemic Diseases in Suzhou, the monitoring of schistosomiasis in the population and snail habitats from 2004 to 2021 was conducted. The Mann-Kendall method and Joinpoint regression method were employed to analyze the trend of epidemic indicators (such as seropositive rate, prevalence of snail frames, etc.). Time series analysis (exponential smoothing model) was conducted to predict snail occurrence. ResultsFrom 2004 to 2021, a total of 73 680 people were serologically tested for schistosomiasis, with a positive rate of 0.084%. The seropositivity rate showed statistically significant differences between different years (χ2=70.73, P<0.05), but there was no significant trend over time. In addition, 3 053 fecal tests were conducted and no positive result was found. The snail habitats covered an area of 70.11 hm2 and showed a decreasing trend (Z=-1.97, P<0.05). A total of 30 093 frames were surveyed, of which 19.038% contained snails. The difference in the prevalence of snail frames between different years was statistically significant (χ2=7 203.09, P<0.05), with a decreasing trend in the prevalence of snail frames (Z=-2.05, P<0.05). A total of 26 296 live snails were seized and density of live snails was 0.874 snails per frame, showing a decreasing trend in the density of live snails (Z=-2.35, P<0.05). A total of 12 391 snails were dissected and no infected snail was found. The areas treated with molluscicides remained stable at 264.60 hm2. An area of 27.77 hm2 achieved the goal of snail eradication through environmental modification, with a decreasing trend (Z=-2.44, P<0.05). It is estimated that the prevalence of snail frames and snail density will remain relatively stable from 2022 to 2026, but the snail habitat area will fluctuate significantly, showing an increasing trend. ConclusionNo indigenous cases of schistosomiasis and no infected snails are reported, indicating the successful consolidation of schistosomiasis prevention and control measures. However, the snail habitat area fluctuates greatly with an increasing trend, suggesting the need for long-term Oncomelania snail monitoring in local areas.

2.
Article | IMSEAR | ID: sea-204847

ABSTRACT

Aims: To know the rainfall and temperature trend for all the districts of Karnataka state to develop suitable coping mechanisms for changing weather conditions during the cropping season. Study Design: The available daily data of rainfall (1971-2011) and minimum and maximum temperature (1971-2007) for each district was collected from NICRA-ICAR website. A non-parametric model such as the Mann-Kendall (MK) test complemented with Sen’s slope estimator was used to determine the magnitude of the trend. Place and Duration of Study: The rainfall data of 41 years (1971-2011) and temperature data of 37 years (1971-2007) was collected for all 27 districts of Karnataka. Methodology: Basic statistics related to rainfall like mean, standard deviation (SD), the coefficient of variation (CV) and the percentage contribution to annual rainfall were computed for monthly and season-wise. Mann-Kendall test was used to detect trend for rainfall as well as temperature. Results: An increasing trend in rainfall during winter, monsoon and annual basis for all most all the districts of Karnataka and decreasing trend of rainfall during pre and post-monsoon season was noticed. An early cessation of rainfall during September month in all most all the districts of Karnataka was observed. Similarly, monthly mean, maximum and the minimum temperature had shown an increasing trend over the past 37 years for all the districts of Karnataka. Conclusion: The more variation in rainfall during the pre-monsoon season was observed, which is more important for land preparation and other operations. The increasing trend of maximum and minimum temperature throughout the year may often cause a reduction in crop yield. It is necessary to change crops with its short duration varieties in order to avoid late season drought.

3.
Article | IMSEAR | ID: sea-204801

ABSTRACT

This study was carried to determine the trend of cocoa yield and climatic variables and assessment of the impact of climate change on the future yield of cocoa in Ondo State, Nigeria. Annual trend statistics for cocoa yield and climatic variables were analyzed for the state using Mann-Kendall test for trend and Sen’s slope estimates. Downscaled data from six Global Circulation Models (GCMs) were used to examine the impact of climate change on the future yield of cocoa in the study area. The results of trends analysis in Ondo State showed that yield decreased monotonically at the rate of 492.18 tonnes/yr (P<0.05). An increased significant trend was established in annual rainfall trend. While Maximum temperature, minimum temperature, and mean temperature all increased at the rate of 0.02/yr (P<0.001). The ensemble of all the GCMs projected a mid-term future decrease of about 9,334 tonnes/yr by 2050 and a long-term future decrease of 13,504 tonnes/yr of cocoa by 2100. The economic implication of these is that, if the projected change in the yield of cocoa as predicted by the ensemble of all the GCMs should hold for the future, it means that Ondo state may experience a loss of about $22,470,018.22 and $32,308,584.32 by the year 2050 and 2100 respectively according to the present price of the commodity in the world market. Measures are to be taken by the government and farmers to find a way of mitigating the impacts of climate change on the future yield of the cocoa study area. This research should be extended to other cocoa producing areas in Nigeria.

4.
Rev. Soc. Bras. Med. Trop ; 52: e20190240, 2019. tab, graf
Article in English | LILACS | ID: biblio-1057251

ABSTRACT

Abstract INTRODUCTION: Brazil experiences a large number of visceral leishmaniasis (VL) cases. Our objective was to examine both spatial patterns of dispersion and space-time trends for this disease. METHODS: We used all autochthonous confirmed cases of VL in Brazil from 2001 to 2017. RESULTS: Throughout Brazil, 53,715 human cases of VL were recorded. The Northeast, Southeast, and Midwest regions of Brazil were the most affected areas and presented a higher risk of transmission. Regarding spatiotemporal variation, significant differences were observed each year, with a peak in 2005. CONCLUSIONS: The dynamics of VL showed a clear non-random pattern of spread in Brazil.


Subject(s)
Humans , Animals , Aged , Dog Diseases/epidemiology , Spatio-Temporal Analysis , Leishmaniasis, Visceral/epidemiology , Brazil/epidemiology , Incidence , Risk Factors , Leishmaniasis, Visceral/veterinary
5.
Eng. sanit. ambient ; 22(1): 13-24, jan.-fev. 2017. tab, graf
Article in Portuguese | LILACS | ID: biblio-840377

ABSTRACT

RESUMO Este artigo apresenta uma análise da tendência temporal e espacial da qualidade das águas superficiais da sub-bacia do Rio das Velhas, inserida na bacia do Rio São Francisco, em Minas Gerais, Brasil. Foram analisados 16.625 dados coletados no período de 2002 a 2011 pelo programa de monitoramento de qualidade das águas superficiais efetuado pelo Instituto Mineiro de Gestão das Águas (Igam). Testes estatísticos, multivariados e não paramétricos foram utilizados para avaliar 11 variáveis físicas, químicas e microbiológicas de 29 estações de monitoramento. Os resultados das análises de tendência Mann-Kendall/Sazonal de Mann-Kendall sugeriram que a maioria dos cursos d'água da região apresentam valores estáveis das variáveis ao longo do período estudado, com maiores alterações associadas a coliformes termotolerantes, demanda bioquímica de oxigênio (DBO), nitrato e índice de qualidade das águas (IQA), principalmente nas proximidades dos grandes centros urbanos. A análise de Cluster definiu três grandes grupos de estações de monitoramento, agrupadas segundo a qualidade de suas águas, correspondentes aos níveis de alta poluição, poluição moderada e baixa poluição. No entanto, ao longo de toda a sub-bacia, foi observada a degradação da qualidade da água durante o período estudado, principalmente relacionada ao lançamento de esgotos domésticos. Uma importante constatação foi a alteração da qualidade da água no baixo Rio das Velhas, apontada pela tendência de redução do IQA em estações localizadas nessa região, o que merece atenção dos órgãos governamentais para ações de manejo.


ABSTRACT This article presents a temporal and spatial trend analysis of the surface waters quality of Velhas River, inserted in the São Francisco basin, in Minas Gerais. It was analyzed 16,625 data collected between 2002 and 2011 by the water quality monitoring program carried out by the Instituto Mineiro de Gestão das Águas (Institute of Water Management of Minas Gerais - IGAM). Statistical tests, multivariate and non-parametric tests were used to assess 11 physical, chemical and microbiological variables of 29 monitoring stations. The results of Mann-Kendall/Sazonal Mann-Kendall trend tests indicated that most of the watercourses in the region showed stable values of the parameters over the study period, with changes associated with thermotolerant coliforms, biochemical oxygen demand (BOD), nitrate and water quality index (IQA) mainly near large urban centers. The Cluster analysis identified three major groups of monitoring stations, grouped according to the quality of its waters, corresponding to high levels of pollution, moderate pollution and low pollution. However, throughout all the sub-basin, it was observed the degradation of the water quality, mainly related to the release of wastewater. An important finding was the worsening of water quality in the low stretch of Velhas River, appointed by the downward trend in the IQA at stations located in this region, which deserves attention of government agencies for management actions.

6.
Braz. arch. biol. technol ; 57(6): 1004-1112, Nov-Dec/2014. tab, graf
Article in English | LILACS | ID: lil-730404

ABSTRACT

The aim of this study was to detect trends in the mean annual streamflow in watersheds of Serra da Mantiqueira Environmental Protection Area, an important Brazilian conservation area located between Minas Gerais, São Paulo and Rio de Janeiro States. Historical series of four selected streamgage stations were analyzed for the periods of 1980-1998 and 1980-2009, using the Mann-Kendall and Regional Mann-Kendall tests. The results showed that the mean annual streamflows of Serra da Mantiqueira Environmental Protection Area watersheds did not change during the complete period of 1980-2009. The tests detected statistically significant trends of reduction of mean annual streamflow during the 1980-1998 period. The confrontation of this result with the inexistence of rainfall trends during the same period suggested that the streamflow changes detected were consequences of changes in the watersheds physical characteristics, and/or increases in water abstraction for multiple uses.

7.
Ciênc. rural ; 44(8): 1360-1366, 08/2014. tab, graf
Article in Portuguese | LILACS | ID: lil-721420

ABSTRACT

Este trabalho teve como objetivo calcular e analisar as séries históricas mensais do Índice de Calor (IC) para Santa Maria, RS, Brasil, no período de 1968 a 2011. As variáveis meteorológicas utilizadas neste trabalho foram pressão atmosférica, temperatura do bulbo seco e temperatura do bulbo úmido, no horário das 9h (12UTC), 15h (18UTC) e 21h (00UTC). Foi realizada análise de tendência das séries históricas para o valor absoluto e a média mensais do IC através do teste de Mann-Kendall e análise de regressão linear simples para quantificar a tendência, com nível de significância de 95% (α=0,05). Para o valor máximo, no horário das 15h (18UTC), as séries históricas para os meses de janeiro e abril apresentaram acréscimo no valor do índice de calor na magnitude de 0,76°C década-1 e 0,92°C década-1, respectivamente. No horário das 21h (00 UTC), os meses de abril e novembro apresentaram aumento de 0,43°C década-1 e 0,55°C década-1, respectivamente. Porém os meses de maio e agosto apresentaram diminuição de 0,69°C década-1 e 0,31°C década-1, respectivamente.


The objective of this study was to calculate and analyze the monthly time series of the Heat Index (HI) for Santa Maria, RS, Brazil, during the period from 1968 to 2011. The meteorological variables used in this study were atmospheric pressure, dry-bulb temperature and wet-bulb temperature at 9am (12UTC), 3pm (18UTC) and 9pm (00UTC). Analysis was performed using the highest absolute and the annual average value of the HI. Trends were tested with the Mann-Kendal test and the magnitude of the trend with the linear regression analysis at 95% (α=0.05). At 3pm (18UTC), the historical series of monthly maximum Heat Index in January and April had an increase of 0.76°C decade-1and 0.92°C decade-1, respectively. At 9pm (00UTC), April and November presented an increase of 0.43°C decade-1 e 0.55°C decade-1, respectively. However, May and August showed a decrease of 0.69°C decade-1 and 0.31°C decade-1, respectively.

8.
Article in English | IMSEAR | ID: sea-162673

ABSTRACT

The topography effects on vegetation biomass under climate change impact have been ignored in prairie regions as it is not as significant as in mountain areas. This paper aims to investigate the topographic effects on vegetation biomass under climate change in semiarid Canadian mixed grass prairie. The study site is Grasslands National Park (GNP) and the study period is from 1985 to 2007. Data used include dry green biomass data sampled from June to July of 2003 to 2005, 10-day Advanced Very High Resolution Radiometer (AVHRR) 1km Normalized Difference Vegetation Index (NDVI) composites of 1985 to 2007, and Global Digital Elevation Model derived from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER GDEM) data with 90 m resolution. To achieve the objective, the applicability of AVHRR NDVI data being a proxy of vegetation biomass was investigated. Then, the range and standard deviation (SD) of each individual vegetation patch in both valley and upland grasslands were calculated. In addition, the variation trend of valley and upland vegetation was analyzed respectively using the Mann-Kendall (M-K) test and the Sen’s slope. The results indicate that the interannual variation of vegetation biomass at GNP can be fairly well represented by AVHRR 1 km NDVI data. Although some patches in valley grassland have similar NDVI range and SD values as those in upland grassland, the others have much smaller range and SD values than the highest range (0.154) and SD (0.045) of upland grassland. The M-K test and Sen’s slope analyses indicate that NDVI had an increase trend with a larger slope (0.0005) in upland and a smaller slope (0.0002) in valley grassland. It is concluded that climatic variation has more effects on upland grassland than valley grassland in GNP. Topography effects in prairie regions should not be ignored.

9.
Article in English | IMSEAR | ID: sea-162672

ABSTRACT

The objective of this study was to investigate precipitation trends in climatic stations in eastern Slovakia. We investigated 20 climatic stations in Slovakia. The studied period was from 1981 to 2010. Monthly precipitation trends were detected by nonparametric Mann- Kendall statistical test. Positive trends of annual as well as monthly precipitation were found in the analyzed rainfall gauging stations in eastern Slovakia. March was observed to have the highest decreasing trends. All other months displayed mostly increasing trends. In quartile research mostly the summer period shows positive trends in precipitation. In conclusion, Slovakia has an increasing trend of precipitation time series.

10.
Ciênc. rural ; 41(5): 789-795, May 2011. ilus, tab
Article in Portuguese | LILACS | ID: lil-590082

ABSTRACT

O objetivo do estudo foi descrever as componentes tendências, periodicidades e persistência temporal presentes nas séries decendiais de precipitação pluvial (PRE) na localidade de Campinas/SP, entre os anos de 1890 e 2009. A aplicação da função auto-correlação e do teste Run permitiu inferir a inexistência de significativas correlações seriais entre os totais decendiais de PRE. Análises espectrais conduzidas no domínio tempo-frequencia não possibilitaram a indicação de significativas periodicidades nos picos de variância do sinal temporal PRE. Com base em métodos não paramétricos e considerando as probabilidades máximas de ocorrência do erro tipo I, usualmente admitidas na literatura (10 e 5 por cento), não houve indicação de marcantes tendências climáticas nas séries analisadas. Contudo, observou-se concentração de casos de tendências de queda a partir do final da época seca regional (mês de agosto) até o início do mês de novembro (pertencente à estação chuvosa). Essa característica pode ser considerada um indício de mudança nos padrões do clima regional no sentido de atraso da retomada da estação chuvosa.


The aim of the study was to evaluate the presence of temporal persistence, periodicals components, and trends within the ten-day rainfall series (PRE), observed during 1890-2009 at the weather station of Campinas, State of São Paulo, Brazil. Based on the autocorrelation function and on the Run test it was observed no significant temporal persistence within the data sample. The spectral analysis carried on the time-frequency domain has shown no remarkable periodicity associated with the variance peaks in the temporal signal under evaluation. Based on non parametric methods and considering the significance levels commonly adopted in the scientific literature (10 and 5 percent) it was detected no important climate trend within the PRE series. However, during the end of the dry season and the beginning of the rainy season it was observed an unexpected high number of decreasing (negative) trends cases that may be an indication of changes in the climatic conditions observed during 1890-2009. This last feature may reveal a delay in the resumption of the rainy season.

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