89 resultados para Temporal structure

em Scielo Saúde Pública - SP


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Temporal and spatial variations in species composition and vertical distribution of macroalgal communities growing on mangrove trees were analyzed bimonthly in the Ilha do Cardoso State Park, São Paulo state (25°03'S and 47°55'W), Southeastern Brazil. The macroalgal communities from mangroves of Perequê and Sítio Grande rivers comprised 10 and 18 taxa respectively. Bostrychia radicans (Mont.) Mont. and B. calliptera (Mont.) Mont. were the predominant taxa, present almost throughout the year and in all the sites studied. The species composition of macroalgal communities from both mangroves presented temporal and spatial variations related to environmental factors. The highest number of taxa was observed during colder, drier months, coinciding with the highest means of high water neap and short periods of continuous emersion (April to August). Some mangrove algae such as B. calliptera, Rhizoclonium spp., Caloglossa spp., and Boodleopsis pusilla (Collins) W. Taylor, Joly et Bernatowicz showed a high degree of tolerance to desiccation, being able to tolerate continuous emersion up to six days. The spatial variations in species composition were related to light, as observed in Catenella caespitosa (Withering) L. Irvine, which occurred in well-lit sites. No pattern of vertical zonation was observed, since Rhizoclonium spp., B. radicans, and B. calliptera occur over the entire vertical range. Variations in the range of vertical distribution of macroalgae of Perequê mangrove were mainly related to the variations in the tidal levels (mean high water neap and/or mean high water spring) while those observed in Sítio Grande mangrove were related to salinity variations, except for B. calliptera and Caloglossa spp. related to tidal levels and high irradiance, respectively.

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INTRODUCTION: The purpose of this ecological study was to evaluate the urban spatial and temporal distribution of tuberculosis (TB) in Ribeirão Preto, State of São Paulo, southeast Brazil, between 2006 and 2009 and to evaluate its relationship with factors of social vulnerability such as income and education level. METHODS: We evaluated data from TBWeb, an electronic notification system for TB cases. Measures of social vulnerability were obtained from the SEADE Foundation, and information about the number of inhabitants, education and income of the households were obtained from Brazilian Institute of Geography and Statistics. Statistical analyses were conducted by a Bayesian regression model assuming a Poisson distribution for the observed new cases of TB in each area. A conditional autoregressive structure was used for the spatial covariance structure. RESULTS: The Bayesian model confirmed the spatial heterogeneity of TB distribution in Ribeirão Preto, identifying areas with elevated risk and the effects of social vulnerability on the disease. We demonstrated that the rate of TB was correlated with the measures of income, education and social vulnerability. However, we observed areas with low vulnerability and high education and income, but with high estimated TB rates. CONCLUSIONS: The study identified areas with different risks for TB, given that the public health system deals with the characteristics of each region individually and prioritizes those that present a higher propensity to risk of TB. Complex relationships may exist between TB incidence and a wide range of environmental and intrinsic factors, which need to be studied in future research.

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The spatial and temporal distribution of a guild of eight diurnal tiger beetle species was studied on a 105 m long transect near the field station of the Reserva Florestal A. Ducke near Manaus (AM), Brazil. The transect followed a path that included both shaded and an open areas. Five of the species, restricted to primary forest, occurrred only in shaded areas of the transect, and three species occurred in open areas. Of all eight species only two of the open habitat species showed no clear seasonality in adult activity. In six species the activity of adults was limited to the rainy season. The most pronounced annual rhythm was found in Pentacomia ventralis, an open habitat species. Activity of adults was limited to October/November. First in-star larvae appeared shortly thereafter. Larval development mainly took place from January to May. The third instar larva entered a dormancy which lasted up to 10 months, and which enabled the synchronisation of emerging adults with annual seasons.

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The aim of this study is to analyze and relate the spatial-temporal variability of macrozoobenthic assemblages to bottom characteristics and salinity fluctuations, in an estuarine shallow water region of Patos Lagoon. Monthly samples, between September 2002 and August 2003, were taken on six sampling stations (distant 90 m). Three biological samples with a 10 cm diameter corer, one sample for sediment analysis, fortnightly bottom topography measurements, and daily data of temperature and salinity were taken from each station. Two biotic and environmental conditions were identified: the first corresponding to spring and summer months, with low macrozoobenthos densities, low values of salinity, small variations in bottom topographic level and weak hydrodynamic activity. A second situation occurred in the months of fall and winter, which showed increased salinity, hydrodynamics and macrobenthos organisms. These results which contrast with previous studies carried out in the area, were attributed to failure in macrozoobenthos recruitments during summer period, especially of the bivalve Erodona mactroides Bosc, 1802 and the tanaid Kalliapseuses schubartii Mañe-Garzón, 1949. This results showed that recruitments of dominant species were influenced by salinity and hydrodynamic conditions.

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We investigated the impact of fish cage culture on the zooplankton community structure in a tropical reservoir. We hypothesized that community abundance is greater near cages and increases over time due to the increase in food availability. Samplings were performed near, upstream and downstream from net cages, and before and after net cage installation. The abundance of zooplankton increased 15 days after the experiment was set up, followed by a reduction and finally increased. Rotifer abundance showed significant differences among sites (p<0.05) and sampling periods (p<0.001). Significant differences were also observed in total zooplankton and cladoceran abundance (p<0.001). The spatial and temporal variation of the physical and chemical variables were indirectly correlated with the structure and dynamic of the zooplankton community, as they indicated the primary production in the environment. Our hypothesis was rejected, since the zooplankton was abundant at the reference site. Only rotifers showed higher abundance near cages, due to the influence of food availability. Community dynamics during the experiment was also correlated to food availability. Our results suggest an impact of fish farming on the zooplankton community.

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Mycobacterium bovis is the causative agent of bovine tuberculosis (TB), a disease that affects approximately 5% of Argentinean cattle. Among the molecular methods for genotyping, the most convenient are spoligotyping and variable number of tandem repeats (VNTR). A total of 378 samples from bovines with visible lesions consistent with TB were collected at slaughterhouses in three provinces, yielding 265 M. bovis spoligotyped isolates, which were distributed into 35 spoligotypes. In addition, 197 isolates were also typed by the VNTR method and 54 combined VNTR types were detected. There were 24 clusters and 27 orphan types. When both typing methods were combined, 98 spoligotypes and VNTR types were observed with 27 clusters and 71 orphan types. By performing a meta-analysis with previous spoligotyping results, we identified regional and temporal trends in the population structure of M. bovis. For SB0140, the most predominant spoligotype in Argentina, the prevalence percentage remained high during different periods, varying from 25.5-57.8% (1994-2011). By contrast, the second and third most prevalent spoligotypes exhibited important fluctuations. This study shows that there has been an expansion in ancestral lineages as demonstrated by spoligotyping. However, exact tandem repeat typing suggests dynamic changes in the clonal population of this microorganism.

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Seasonality was studied for Alticini trapped with malaise over a period of two years in the Vila Velha State Park, Parana, Brazil. Coleoptera, Chrysomelidae and Alticini showed seasonal distribution, with the highest abundance during spring and summer months. The abundance peaks of these groups were not synchronized. Of all environmental variables tested, photoperiod had the larger effect on the distributional patterns of Coleoptera, Chrysomelidae and Alticini. Also, Chrysomelidae and Alticini probably are related to the quality and availability of host-plants. When richness was high there was a greater similarity among seasons of different years. However, when richness was not pronounced, seasons showed more similarity within the same year than between years. The Alticini community was seasonally structured and a possible mechanism underlying this pattern is asymmetric competition. Nevertheless, it is necessary to account for indirect interactions (plant-enemy mediated) to better understand how Alticini community is structured.

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Alticini fauna from five areas, two with different types of management (Borda and Araucaria) and three with different levels of conservation (Fase 1, Fase 2 and Fase 3), in the Araucaria Forest of the Parana was captured with malaise traps. The material was collected weekly, from September/1999 to August/2001, in the Parque Estadual of Vila Velha, Ponta Grossa. 1,891 individuals of 106 Alticini species were collected with only seven species common to all areas. Despite the proximity between sampling areas, the number of species shared between pairs of areas was low, not reaching 40%, with the Araucaria and Fase 1 areas being the most similar. The community structure of the areas Fase 1 and Fase 2 were most related. Fase 1, in initial stage of succession, showed the largert variation in the abundance and richness from one year to another.

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The study of organisms and their resources is critical to further understanding population dynamics in space and time. Although drosophilids have been widely used as biological models, their relationship with breeding and feeding sites has received little attention. Here, we investigate drosophilids breeding in fruits in the Brazilian Savanna, in two contrasting vegetation types, throughout 16 months. Specifically, larval assemblages were compared between savannas and forests, as well as between rainy and dry seasons. The relationships between resource availability and drosophilid abundance and richness were also tested. The community (4,022 drosophilids of 23 species and 2,496 fruits of 57 plant taxa) varied widely in space and time. Drosophilid assemblages experienced a strong bottleneck during the dry season, decreasing to only 0.5% of the abundance of the rainy season. Additionally, savannas displayed lower richness and higher abundance than the forests, and were dominated by exotic species. Both differences in larval assemblages throughout the year and between savannas and gallery forests are consistent with those previously seen in adults. Although the causes of this dynamic are clearly multifactorial, resource availability (richness and abundance of rotten fruits) was a good predictor of the fly assemblage structure.

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Temporal (monthly in three fields for 12 months) and spatial (once in 23 fields during March-April) samplings were conducted in the major soybean (Glycine max)-growing region of the Brazilian Federal District. Fifty-three nematode genera were found in both samplings, but 13 were detected only by the temporal sampling, and one only by the spatial sampling. Fifty-three percent were plant-parasites, 35% were bacterivores, and about 12% were fungivores, predators and omnivores constituted the community that was dominated by the genera Helicotylenchus (40% of total abundance), Acrobeles (15%), Cephalobus (7.6%), Meloidogyne(5.6%) and Pratylenchus (4.9%). Heterodera glycines was not found in this study. There were no differences in ten ecological measurements [Ds, H', Es, T, FF/BF, (FF+BF)/PP, MI, PPI, mMI, and Dorylaimida (%)] between the two sampling types, but differences in indexes d and J'. Plant parasite populations dropped at the end of the crop cycle, remained at low levels during the dry season and the seedling period, then increased again in the crop-growing season. Fungivores maintained their low populations throughout the year, increasing only in June and July, the post-harvest period, when soil fungi decomposed root tissue. The population of bacterivores slightly declined during the dry season and the initial rainy season, but peaked in the middle of the rainy season, apparently associated with soil humidity. In the five most abundant nematodes, those of Acrobeles and Pratylenchus were more populous in wet soils, Cephalobus and Meloidogyne adapted well in dry soils, but Helicotylenchus survived abundantly in a wide range of soil moisture.

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This study aimed to describe the probabilistic structure of the annual series of extreme daily rainfall (Preabs), available from the weather station of Ubatuba, State of São Paulo, Brazil (1935-2009), by using the general distribution of extreme value (GEV). The autocorrelation function, the Mann-Kendall test, and the wavelet analysis were used in order to evaluate the presence of serial correlations, trends, and periodical components. Considering the results obtained using these three statistical methods, it was possible to assume the hypothesis that this temporal series is free from persistence, trends, and periodicals components. Based on quantitative and qualitative adhesion tests, it was found that the GEV may be used in order to quantify the probabilities of the Preabs data. The best results of GEV were obtained when the parameters of this function were estimated using the method of maximum likelihood. The method of L-moments has also shown satisfactory results.

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A displasia fibrosa do osso temporal é uma doença de etiologia ainda controversa, manifestando-se principalmente por estenose progressiva do conduto auditivo externo e pela perda condutiva da audição. Outras manifestações incluem abaulamento na região temporal ou retroauricular, otorréia, otalgia e disacusia sensório-neural. A incidência é maior no sexo masculino e acomete principalmente a raça branca. O exame radiológico característico demonstra um aspecto de "vidro-fosco" homogêneo envolvido por uma concha de tecido cortical denso, embora existam outros padrões radiológicos desta enfermidade. O exame microscópico demonstra um trabeculado ósseo semelhante aos caracteres chineses. Este estudo relata dois casos de displasia fibrosa do osso temporal que se destacam, pois ultrapassaram o osso temporal, acometendo a região zigomática, sendo que no segundo caso houve também comprometimento do osso esfenóide e o pterigóide. Os pacientes foram submetidos à mastoidectomia radical modificada e tiveram boa evolução.

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Displasia fibrosa é uma doença caracterizada por progressiva substituição dos elementos normais do osso por tecido fibroso. É uma patologia benigna incomum de etiologia desconhecida. Existem duas categorias primárias da doença: displasia fibrosa monostótica que envolve somente um osso e displasia fibrosa poliostótica acometendo múltiplos ossos. Embora o esqueleto crânio-facial seja sede freqüente da doença, o osso temporal raramente está envolvido. O envolvimento do osso temporal tem como sintoma mais comum a surdez. O diagnóstico é baseado em imagens radiológicas. Quando a displasia fibrosa é acompanhada por sintomas clínicos significantes, o tratamento cirúrgico é recomendado. O acompanhamento clínico do paciente é fundamental para o diagnóstico precoce de recidivas. Neste artigo relatamos um caso de displasia fibrosa do osso temporal e revisão da patologia na literatura.

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As osteodistrofias do osso temporal podem se manifestar de diversas maneiras, como envolvimento restrito ao osso temporal ou com envolvimento de outros ossos do crânio ou ainda fazerem parte de uma manifestação sistêmica. Consideramos, em nosso trabalho, duas entidades como osteodistofias raras, a osteopetrose e a doença de Camurati-Engelmann, esta última de incidência extremamente rara, com poucos relatos na literatura. Apresentamos dois casos de osteopetrose em sua forma benigna (doença de Albers-Schöenberg), um paciente de 11 anos e outro de 48 anos, ambos do sexo masculino, e um paciente de 28 anos do sexo feminino com a doença de Camurati-Engelmann (displasia diafisária hereditária progressiva), doenças hereditárias autossômicas que apresentam sintomas diversos. A paralisia facial periférica se manifestou em dois dos nossos pacientes. Discutimos alguns aspectos relacionados às manifestações clínicas destas doenças, achados radiológicos, assim como o diagnóstico diferencial e a conduta terapêutica diante de complicações das doenças.

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O tratamento dos tumores glômicos tem sido motivo de controvérsia desde sua primeira publicação, podendo ser cirúrgico, radioterápico ou apenas expectante. OBJETIVO: O objetivo do estudo foi avaliar a efetividade e as complicações do tratamento radioterápico para esses tumores. FORMA DE ESTUDO: clínico com coorte transversal. MATERIAL E MÉTODO: Trata-se de uma coorte histórica de pacientes com tumor glômico jugular submetidos à radioterapia. Os critérios de controle da doença foram não haver progressão dos sintomas ou disfunção de nervos cranianos, sem aumento do tamanho da lesão ao exame físico ou controle radiológico. Avaliamos também a presença de seqüelas do tratamento. RESULTADOS: Foram incluídos 12 pacientes, sendo oito mulheres. O tempo de follow-up variou de 3 a 35 anos, com uma media de 11,6 anos. Os principais sintomas foram: hipoacusia, zumbido pulsátil e tontura ou vertigem. Os achados de exame físico mais freqüentes foram massa pulsátil retrotimpanica, paralisia facial e anacusia, sendo os tumores estadiados segundo a classificação proposta por Fisch. A radioterapia foi realizada com acelerador linear com doses variando de 4500-5500 Rads por 4-6 semanas. As seqüelas mais comuns foram a dermatite, estenose do conduto auditivo externo, anacusia e paralisia facial. DISCUSSÃO: Os sintomas e achados de exame físico e o método e dosagem da radioterapia não diferiram daqueles encontrados na literatura. Todos os pacientes tiveram melhora dos sintomas e apenas um não foi considerado como tendo controle da doença. As complicações do tratamento foram de pouca repercussão, com exceção da anacusia e da paralisia facial. CONCLUSÃO: A radioterapia é uma alternativa viável para o tratamento desses tumores pela boa resposta e baixo índice de complicações. Deve ser considerada especialmente em tumores mais avançados onde um procedimento cirúrgico pode trazer grande morbidade.