994 resultados para Spatiotemporal patterns


Relevância:

20.00% 20.00%

Publicador:

Resumo:

The obligate intracellular bacterium Chlamydia trachomatis is a human pathogen of major public health significance. Strains can be classified into 15 main serovars (A to L3) that preferentially cause ocular infections (A-C), genital infections (D-K) or lymphogranuloma venereum (LGV) (L1-L3), but the molecular basis behind their distinct tropism, ecological success and pathogenicity is not welldefined. Most chlamydial research demands culture in eukaryotic cell lines, but it is not known if stains become laboratory adapted. By essentially using genomics and transcriptomics, we aimed to investigate the evolutionary patterns underlying the adaptation of C. trachomatis to the different human tissues, given emphasis to the identification of molecular patterns of genes encoding hypothetical proteins, and to understand the adaptive process behind the C. trachomatis in vivo to in vitro transition. Our results highlight a positive selection-driven evolution of C. trachomatis towards nichespecific adaptation, essentially targeting host-interacting proteins, namely effectors and inclusion membrane proteins, where some of them also displayed niche-specific expression patterns. We also identified potential "ocular-specific" pseudogenes, and pointed out the major gene targets of adaptive mutations associated with LGV infections. We further observed that the in vivo-derived genetic makeup of C. trachomatis is not significantly compromised by its long-term laboratory propagation. In opposition, its introduction in vitro has the potential to affect the phenotype, likely yielding virulence attenuation. In fact, we observed a "genital-specific" rampant inactivation of the virulence gene CT135, which may impact the interpretation of data derived from studies requiring culture. Globally, the findings presented in this Ph.D. thesis contribute for the understanding of C.trachomatis adaptive evolution and provides new insights into the biological role of C. trachomatishypothetical proteins. They also launch research questions for future functional studies aiming toclarify the determinants of tissue tropism, virulence or pathogenic dissimilarities among C. trachomatisstrains.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

INTRODUCTION: Control strategies to eliminate the transmission of Chagas disease by insect vectors have significantly decreased the number of reported acute cases in Brazil. However, data regarding the incidence and distribution of acute Chagas disease cases in the State of Pernambuco are unavailable in the literature. METHODS: A geographical information system was used to delineate the spatiotemporal distribution profile of the cases from 2002 to 2013 in 185 municipalities of Pernambuco based on the municipality where notification occurred. The results were presented in digital maps generated by the TerraView software (INPE). RESULTS: A total of 302 cases of acute disease were recorded in 37.8% of the municipalities, for a total of 0.13 cases per 1,000,000 inhabitants per year. Out of the 302 cases, 99.3% were reported between 2002 and 2006. The most affected municipalities were Carnaubeira da Penha, Mirandiba and Terra Nova. The risk maps showed a significant decrease in the number of notifications and a concentration of cases in the Midwest region. CONCLUSIONS: This study highlights a significant decrease in new cases of acute Chagas disease in Pernambuco starting in 2006 when Brazil received an international certification for the interruption of vectorial transmission by Triatoma infestans. However, control strategies should still be encouraged because other triatomine species can also transmit the parasite; moreover, other transmission modes must not be neglected.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This article argues that the study of literary representations of landscapes can be aided and enriched by the application of digital geographic technologies. As an example, the article focuses on the methods and preliminary findings of LITESCAPE.PT—Atlas of Literary Landscapes of Mainland Portugal, an on-going project that aims to study literary representations of mainland Portugal and to explore their connections with social and environmental realities both in the past and in the present. LITESCAPE.PT integrates traditional reading practices and ‘distant reading’ approaches, along with collaborative work, relational databases, and geographic information systems (GIS) in order to classify and analyse excerpts from 350 works of Portuguese literature according to a set of ecological, socioeconomic, temporal and cultural themes. As we argue herein this combination of qualitative and quantitative methods—itself a response to the difficulty of obtaining external funding—can lead to (a) increased productivity, (b) the pursuit of new research goals, and (c) the creation of new knowledge about natural and cultural history. As proof of concept, the article presents two initial outcomes of the LITESCAPE.PT project: a case study documenting the evolving literary geography of Lisbon and a case study exploring the representation of wolves in Portuguese literature.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Abstract: INTRODUCTION : Several municipalities of the Western region of the State of São Paulo have been affected by human visceral leishmaniasis (HVL), including the City of Adamantina, where the first autochthonous cases occurred in 2004. Therefore, this study aimed to describe the spatial and spatiotemporal occurrence of HVL in Adamantina. METHODS : Secondary data regarding the occurrence of HVL in Adamantina between 2004 and 2011 were used. Incidence, mortality, and case fatality rates were calculated. We used local empirical Bayesian incidence rates to represent the occurrence of the disease in the census sector of the city. The existence of spatial and spatiotemporal clusters of cases was evaluated using scan statistics. In situ observation was performed to assess the socioeconomic and environmental characteristics of the areas with medium and high incidences. RESULTS : Adamantina reported cases in 70% of its census sectors. No differences were observed between sexes. The group aged 0-4 years presented the highest incidence and mortality rates, and the group aged 40-59 years presented the highest fatality rate. We detected a spatiotemporal cluster, which coincided with the commencement of the endemic in the city. CONCLUSIONS : The individuals most affected by the disease were children. The disease was present in areas with better and worse socioeconomic conditions. The use of spatial analysis techniques was important to achieve the study objectives.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Gastrointestinal mesenchymal tumors comprise a rare group of gastrointestinal tract wall tumors that have long been a source of confusion and controversy, especially in terms of pathological classification, preoperative diagnosis, management strategies, and prognosis. This report describes the clinical manifestations and management of 2 rectal leiomyomas and reviews the pertinent literature. Case 1: A 44-year-old woman was admitted reporting a nodule in the right para-anal region for the previous 2 years. At proctological examination, a 4-cm diameter fibrous mass situated in the para-anal region that produced an arch under the smooth muscle on the right rectal wall just above the anorectal ring was noted. Computed tomography and magnetic resonance imaging of the abdomen and pelvis showed the lesion and detected no other abnormalities. Surgical treatment consisted of wide local resection of the tumor through a para-anal incision, with no attempts to perform lymphadenectomy. Case 2: A 40-year-old male patient was admitted reporting constant anal pain for 4 months. He presented a 3-cm submucosal nodule at the anterior rectal wall just above the dentate line. After 2 inconclusive preoperative biopsies, transanal resection of the tumor was performed. Histological analysis of the specimen showed a benign leiomyoma. A review of the literature is presented, emphasizing some clinical and therapeutic aspects of this unusual rectal tumor.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We present a study on human mobility at small spatial scales. Differently from large scale mobility, recently studied through dollar-bill tracking and mobile phone data sets within one big country or continent, we report Brownian features of human mobility at smaller scales. In particular, the scaling exponents found at the smallest scales is typically close to one-half, differently from the larger values for the exponent characterizing mobility at larger scales. We carefully analyze 12-month data of the Eduroam database within the Portuguese university of Minho. A full procedure is introduced with the aim of properly characterizing the human mobility within the network of access points composing the wireless system of the university. In particular, measures of flux are introduced for estimating a distance between access points. This distance is typically non-Euclidean, since the spatial constraints at such small scales distort the continuum space on which human mobility occurs. Since two different ex- ponents are found depending on the scale human motion takes place, we raise the question at which scale the transition from Brownian to non-Brownian motion takes place. In this context, we discuss how the numerical approach can be extended to larger scales, using the full Eduroam in Europe and in Asia, for uncovering the transi- tion between both dynamical regimes.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

During the last few years many research efforts have been done to improve the design of ETL (Extract-Transform-Load) systems. ETL systems are considered very time-consuming, error-prone and complex involving several participants from different knowledge domains. ETL processes are one of the most important components of a data warehousing system that are strongly influenced by the complexity of business requirements, their changing and evolution. These aspects influence not only the structure of a data warehouse but also the structures of the data sources involved with. To minimize the negative impact of such variables, we propose the use of ETL patterns to build specific ETL packages. In this paper, we formalize this approach using BPMN (Business Process Modelling Language) for modelling more conceptual ETL workflows, mapping them to real execution primitives through the use of a domain-specific language that allows for the generation of specific instances that can be executed in an ETL commercial tool.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Programa Doutoral em Matemática e Aplicações.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The biology and ecology of South American turtles is still poorly known, particularly, for the Brazilian species. Laboratory studies are essential to understand the life cycles of aquatic turtles species and to help in formulating management plans for their conservation. As a contribution to the knowledge of Podocnemis erythrocephala species, we give a description of its species-typical behaviors, categorized as: maintenance, locomotion, feeding, agonistic and reproduction, based on captives observations of four pairs of turtles in an aquarium in Manaus, Brazil. Similarities and differences with the repertoires of other turtle species are discussed, concluding that turtles have much more complex adaptative strategies and social life than was believed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Wild boar (Sus scrofa) and red deer (Cervus elaphus) are the main maintenance hosts for bovine tuberculosis (bTB) in continental Europe. Understanding Mycobacterium tuberculosis complex (MTC) excretion routes is crucial to define strategies to control bTB in free-ranging populations, nevertheless available information is scarce. Aiming at filling this gap, four different MTC excretion routes (oronasal, bronchial-alveolar, fecal and urinary) were investigated by molecular methods in naturally infected hunter-harvested wild boar and red deer. In addition MTC concentrations were estimated by the Most Probable Number method. MTC DNA was amplified in all types of excretion routes. MTC DNA was amplified in at least one excretion route from 83.0% (CI95 70.8-90.8) of wild ungulates with bTB-like lesions. Oronasal or bronchial-alveolar shedding were detected with higher frequency than fecal shedding (p < 0.001). The majority of shedders yielded MTC concentrations <10(3) CFU/g or mL. However, from those ungulates from which oronasal, bronchial-alveolar and fecal samples were available, 28.2% of wild boar (CI95 16.6-43.8) and 35.7% of red deer (CI95 16.3-61.2) yielded MTC concentrations >10(3) CFU/g or mL (referred here as super-shedders). Red deer have a significantly higher risk of being super-shedders compared to wild boar (OR = 11.8, CI95 2.3-60.2). The existence of super-shedders among the naturally infected population of wild boar and red deer is thus reported here for the first time and MTC DNA concentrations greater than the minimum infective doses were estimated in excretion samples from both species.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper aimed to evaluate the richness, abundance and frequency of sand fly occurrence in rural and urban areas American visceral Leishmaniasis -AVL is endemic in the study area of Santarém municipality, Pará state. Sand flies were collected during 1995-2000, using CDC light traps placed in neighborhoods and rural areas of the municipality. A total of 53.454 individuals and 26 species of sand flies were collected. The most abundant species in both urban and rural environments was Lutzomyia longipalpis, vector of AVL in the area. The highest species richness by capture was in rural area. In all years sampled, the largest number of species of sand fly collected was always in rural areas. The species of sand flies in urban and rural area were similar in 11 species. In the rural area other 11 species were found, a total of 22 species. Shannon-Wiener index ranged from 0.12 to 0.84 at rural areas and 0.08 to 0.34 at urban ones. In general, rural localities showed higher diversity (H') of phlebotomines than urban ones. Individual-based rarefaction curves for each area demonstrated that urban localities had the lowest expected number of phlebotomine species and the richest rural ones reach higher expected values with lower amount of individuals than urban sites. The most frequent species were Lutzomyia longipalpis, Evandromyia carmelinoi and Bichromomyia flaviscutellata.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

OBJECTIVE: To identiy left ventricular geometric patterns in hypertensive patients on echocardiography, and to correlate those patterns with casual blood pressure measurements and with the parameters obtained on a 24-hour ambulatory blood pressure monitoring. METHODS: We studied sixty hypertensive patients, grouped according to the Joint National Committee stages of hypertension.. Using the single- and two-dimensional Doppler Echocardiography, we analyzed the left ventricular mass and the geometric patterns through the correlation of left ventricular mass index and relative wall thickness. On ambulatory blood pressure monitoring we assessed the means and pressure loads in the different geometric patterns detected on echocardiography RESULTS: We identified three left ventricular geometric patterns: 1) concentric hypertrophy, in 25% of the patients; 2) concentric remodeling, in 25%; and 3) normal geometry, in 50%. Casual systolic blood pressure was higher in the group with concentric hypertrophy than in the other groups (p=0.001). Mean systolic pressure in the 24h, daytime and nighttime periods was also higher in patients with concentric hypertrophy, as compared to the other groups (p=0.003, p=0.004 and p=0.007). Daytime systolic load and nighttime diastolic load were higher in patients with concentric hypertrophy ( p=0.004 and p=0.01, respectively). CONCLUSIONS: Left ventricular geometric patterns show significant correlation with casual systolic blood pressure, and with means and pressure loads on ambulatory blood pressure monitoring.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

PURPOSE: To evaluate 2 left ventricular mass index (LVMI) normality criteria for the prevalence of left ventricular geometric patterns in a hypertensive population ( HT ) . METHODS: 544 essential hypertensive patients, were evaluated by echocardiography, and different left ventricular hypertrophy criteria were applied: 1 - classic : men - 134 g/m² and women - 110 g/m² ; 2- obtained from the 95th percentil of LVMI from a normotensive population (NT). RESULTS: The prevalence of 4 left ventricular geometric patterns, respectively for criteria 1 and 2, were: normal geometry - 47.7% and 39.3%; concentric remodelying - 25.4% and 14.3%; concentric hypertrophy - 18.4% and 27.7% and excentric hypertrophy - 8.8% and 16.7%, which confered abnormal geometry to 52.6% and 60.7% of hypertensive. The comparative analysis between NT and normal geometry hypertensive group according to criteria 1, detected significative stuctural differences,"( *p < 0.05):LVMI- 78.4 ± 1.50 vs 85.9 ±0.95 g/m² *; posterior wall thickness -8.5 ± 0.1 vs 8.9 ± 0.05 mm*; left atrium - 33.3 ± 0.41 vs 34.7 ± 0.30 mm *. With criteria 2, significative structural differences between the 2 groups were not observed. CONCLUSION: The use of a reference population based criteria, increased the abnormal left ventricular geometry prevalence in hypertensive patients and seemed more appropriate for left ventricular hypertrophy detection and risk stratification.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The case of a 16-year-old patient with atrioventricular tachycardia caused by a single left anterolateral accessory pathway is reported. When the patient underwent radiofrequency ablation, a lesion on the mitral annulus lateral wall produced changes in the retrograde atrial activation pattern determined by that pathway; changes ranged from a delay in depolarization of the annulus posterior portions to full left atrium counterclockwise activation. Such phenomena were probably caused by a block in the isthmus between the annulus and the lower left pulmonary vein ostium. This case illustrates the importance of the mitral-pulmonary isthmus in the process of left atrium activation, an alert to changes induced by its unintentional block during accessory pathway ablation.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Identificación y caracterización del problema objeto de estudio: Diversas investigaciones señalan que el uso o consumo de alcohol comienza durante la adolescencia. En este periodo del desarrollo típicamente se han reportado deterioros asociados con el consumo de alcohol sobre diversas funciones cognitivas. Sin embargo, los hallazgos no siempre han sido concluyentes. Hipótesis: a) Existe una mayor cantidad de déficits neuropsicológicos (especialmente en los dominios asociados con la toma de decisiones) en los grupos de adolescentes que presentan patrones de consumo elevados o tipo binge y en los adolescentes bajo tratamiento; b) Existen sesgos cognitivos de tipo implícito en los adolescentes expuestos a publicidades referidas a bebidas alcohólicas; y c) Existe mayor presencia de expectativas negativas en el grupo conformado por niños, así como una mayor presencia de expectativas positivas en el grupo conformado por adolescentes. Planteo de Objetivos: se pretende lograr un perfil neuropsicológico de adolescentes de ambos sexos en función de patrones de consumo de alcohol bien diferenciados. Asimismo, se intentará determinar la presencia de sesgos cognitivos hacia estímulos asociados con el alcohol en función de las expectativas hacia el psicotrópico y el tipo de consumo del mismo que presenta la población bajo estudio. Finalmente, se buscará determinar si existen cambios evolutivos en las expectativas hacia el alcohol que pudieran indicar la presencia de mayor vulnerabilidad al consumo de alcohol. Materiales y métodos a utilizar: Se utilizarán pruebas neuropsicológicas (IGT, WCST, otras) y cognitivas (AEQ o similares). Se apelará al uso de diseños ex post facto prospectivos de tipo simple o factoriales, diseños factoriales, estudios instrumentales y estudios descriptivos de poblaciones mediante encuestas. Resultados esperados: 1) Se espera encontrar una mayor cantidad de déficits neuropsicológicos (especialmente en los dominios asociados con la toma de decisiones) en los grupos de adolescentes con patrones de consumo de alcohol elevados y binge, así como en el grupo de adolescentes bajo tratamiento. 2) Se espera encontrar la presencia de sesgos cognitivos implícitos en aquellos adolescentes expuestos a publicidades referidas a bebidas alcohólicas en contraposición a los adolescentes expuestos a publicidades de bebidas no-alcohólicas. 3) Se espera encontrar una mayor presencia de expectativas negativas en el grupo conformado por niños, y una mayor presencia de expectativas positivas en el grupo conformado por adolescentes, con lo que se verificaría el supuesto que señala que las EA se modifican a lo largo del desarrollo. Asimismo, se espera confirmar que las EA cambian en función de la experiencia de consumo de alcohol. Importancia del proyecto: En el ámbito local no se han realizado estudios sistemáticos de esta naturaleza, la información que se obtenga permitirá evaluar el impacto del uso y abuso de alcohol durante la adolescencia así como diseñar y ejecutar mejores estrategias de prevención y de rehabilitación y, al mismo tiempo, facilitará la toma de decisiones en el campo de la planificación de políticas sanitarias dirigidas a los adolescentes.