23 resultados para Final state Interaction

em Scielo Saúde Pública - SP


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Pulse Response Based Control (PRBC) is a recently developed minimum time control method for flexible structures. The flexible behavior of the structure is represented through a set of discrete time sequences, which are the responses of the structure due to rectangular force pulses. The rectangular force pulses are given by the actuators that control the structure. The set of pulse responses, desired outputs, and force bounds form a numerical optimization problem. The solution of the optimization problem is a minimum time piecewise constant control sequence for driving the system to a desired final state. The method was developed for driving positive semi-definite systems. In case the system is positive definite, some final states of the system may not be reachable. Necessary conditions for reachability of the final states are derived for systems with a finite number of degrees of freedom. Numerical results are presented that confirm the derived analytical conditions. Numerical simulations of maneuvers of distributed parameter systems have shown a relationship between the error in the estimated minimum control time and sampling interval

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Twenty species of Tephritidae (Diptera) are recorded in association with capitula of plants in the family Asteraceae. The Tephritidae genus Tetreuarestais registered for Rio Grande do Sul for the first time. Five species of Tephritidae are newly recorded for Rio Grande do Sul, and new hosts are recorded for the following fly species: Dioxyna chilensis (Macquart), Plaumannimyia dolores (Hering), Plaumannimyia imitatrix (Hering), Plaumannimyia miseta(Hering), Plaumannimyia pallensHering, Tomoplagia incompleta (Williston), Tomoplagia matzenbacheriPrado, Norrbom & Lewinsohn, Tomoplagia reimoseriHendel, Xanthaciura biocellata(Thomson) and Xanthaciura chrysura(Thomson).

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The objective of this work was to investigate the genotype-environment interaction in Mato Grosso State, MT. The relative importance of locations, years, sowing dates and cultivars and their interactions was analyzed from data collected in regional yield trials performed in a randomized complete block design with four replications, from 1994-1995 through 1999-2000, in nine locations and two sowing dates. Individual and pooled analyses of variance over years and locations were performed. Complementary analyses of variances partitioned MT State in two main and five smaller regions, respectively: North and South of Cuiabá; and MT-South-A (Pedra Preta area), MT-South-B (Rondonópolis and Itiquira), MT-East (Primavera do Leste and Campo Verde), MT-Central (Nova Mutum, Lucas do Rio Verde and Sorriso) and MT-Parecis (Campo Novo dos Parecis and Sapezal). Locations are relatively more important than years for yield testing soybeans in the MT State, therefore, investment should be made in increasing locations rather than years to improve experimental precision. Partitioning the MT State into regions has little impact on soybean yield testing results and, consequently, on the efficiency of the soybean breeding program in the State. Breeding genotypes with broad adaptation for the MT State is an efficient strategy for cultivar development.

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Cyanide-resistant alternative oxidase (AOX) is not limited to plant mitochondria and is widespread among several types of protists. The uncoupling protein (UCP) is much more widespread than previously believed, not only in tissues of higher animals but also in plants and in an amoeboid protozoan. The redox energy-dissipating pathway (AOX) and the proton electrochemical gradient energy-dissipating pathway (UCP) lead to the same final effect, i.e., a decrease in ATP synthesis and an increase in heat production. Studies with green tomato fruit mitochondria show that both proteins are present simultaneously in the membrane. This raises the question of a specific physiological role for each energy-dissipating system and of a possible functional connection between them (shared regulation). Linoleic acid, an abundant free fatty acid in plants which activates UCP, strongly inhibits cyanide-resistant respiration mediated by AOX. Moreover, studies of the evolution of AOX and UCP protein expression and of their activities during post-harvest ripening of tomato fruit show that AOX and plant UCP work sequentially: AOX activity decreases in early post-growing stages and UCP activity is decreased in late ripening stages. Electron partitioning between the alternative oxidase and the cytochrome pathway as well as H+ gradient partitioning between ATP synthase and UCP can be evaluated by the ADP/O method. This method facilitates description of the kinetics of energy-dissipating pathways and of ATP synthase when state 3 respiration is decreased by limitation of oxidizable substrate.

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Considering that the number of day-care centers for pre-school-age children has expanded rapidly in developing countries, and that these institutions presenting conditions that facilitate the transmission of many enteric agents, a parasitological survey was carried out in three municipal day-cares from Botucatu: two in the urban area (one in downtown area and the other one in the city periphery area) and the third in the rural area. Three separate stool specimens were collected from 147 children ranging from 0 to 72 months old and 20 staff members. Each stool specimen was processed by Lutz and zinc sulfate flotation methods. The frequency of giardiasis observed among children of downtown, periphery and rural day-cares was 69.6%, 52.7% and 69.6%, respectively. Only one employee was positive for G. lamblia. The examination of three stool specimens increased the positivity for G. lamblia: from the ninety three final positive examinations, 24 (25.5%) and 8 (8.5%) were positives only after examination of the second and third samples, respectively. Others intestinal organisms like Ascaris lumbricoides (20.4%), Trichuris trichiura (19.0%). Hymenolepis nana (8.8%), Entamoeba coli (22.4%) and Blastocystis hominis (32.0%) were frequently found in the children. There was no significant association among localization of the day-cares, sex of the children and the levels of G. lamblia infection. According to the age, G. lamblia was found mainly in children between 12 to 47 months old.

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SUMMARYCryptococcosis is a severe systemic mycosis caused by two species of Cryptococcus that affect humans and animals: C. neoformans and C. gattii. Cosmopolitan and emergent, the mycosis results from the interaction between a susceptible host and the environment. The occurrence of C. neoformanswas evaluated in 122 samples of dried pigeon excreta collected in 49 locations in the City of Cuiabá, State of Mato Grosso, Brazil, including public squares (n = 5), churches (n = 4), educational institutions (n = 3), health units (n = 8), open areas covered with asbestos (n = 4), residences (n = 23), factory (n = 1) and a prison (n = 1). Samples collected from July to December of 2010 were seeded on Niger seed agar (NSA). Dark brown colonies were identified by urease test, carbon source assimilation tests and canavanine-glycine-bromothymol blue medium. Polymerase chain reaction primer pairs specific for C. neoformans were also used for identification. Cryptococcus neoformans associated to pigeon excreta was isolated from eight (6.6%) samples corresponding to six (12.2%) locations.Cryptococcus neoformans was isolated from urban areas, predominantly in residences, constituting a risk of acquiring the disease by immunocompromised and immunocompetent individuals.

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INTRODUCTION: Reduction in the vertical transmission of HIV is possible when prophylactic measures are implemented. Our objective was to determine demographic characteristics of HIV-infected pregnant women and the rate of mother-to-child transmission of HIV in Manaus, Amazonas, Brazil. METHODS: A descriptive study was conducted using notification, and investigating data from the Notifiable Diseases Data System in the Brazilian State of Amazonas, between 2007 and 2009. RESULTS: During the study period, notification was received of 509 HIV-positive pregnant women. The vertical transmission was 9.9% (95% CI: 7.2-12.6%). The mean age of women was 27 years (SD: 5.7), and the majority (54.8%) had not completed elementary school (eighth grade). Diagnosis of HIV seropositivity was made prior to pregnancy in 115 (22.6%) women, during prenatal care in 302 (59.3%), during delivery in 70 (13.8%), and following delivery in 22 (4.3%). Four hundred four of these women (79.4%) had had prenatal care, with 79.4% of patients receiving antiretroviral during pregnancy and 61.9% of the newborn infants receiving prophylaxis. In the final multivariate logistic regression model, living in urban area [OR = 0.7 (95% CI: 0.35-0.89)] and having had prenatal care [OR = 0.1 (95% CI: 0.04-0.24)] remained as protective factors against vertical HIV transmission in this population. CONCLUSIONS: The relevance of adequate compliance with the measures already established as being effective in guaranteeing a reduction in HIV transmission within the maternal and infant population should be emphasized.

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Introduction The blood meal source of sandflies provides valuable information about the vector/host interaction and allows for an understanding of American cutaneous leishmaniasis (ACL) transmission mechanisms. The aim of this study was to identify the blood meal sources of Lutzomyia (Nyssomyia) intermedia in an endemic area of leishmaniasis in Brazil's State of Paraná using a precipitin test. Methods Sandflies were collected in the rural locality of Epitácio Pessoa within the City of Adrianópolis, State of Paraná, in southern Brazil. A total of 864 female sandflies were captured, and 862 (99.8%) were identified as L. intermedia species. However, two unidentified specimens were considered to be part of the genus Lutzomyia. Results Among the females examined, 396 specimens presented reactions to a certain type of tested antiserum, and most (67.9%) reacted to the simple type. These sandflies fed mainly on the blood of birds, opossums, and rodents, but specimens that fed on the blood of humans, dogs, horses, cattle, and cats were also found. Among the cross-reactions found (32.1%), bird/rodent, bird/opossum, bird/dog, bird/human, and horse/dog cross-reactions were the most common. Conclusions These results demonstrate a tendency in the eclectic feeding behavior of L. intermedia and support its potential role as a vector for ACL in the study area.

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Background: Cardiovascular Diseases (CVD) are the leading cause of death in Brazil. Objective: To estimate total CVD, cerebrovascular disease (CBVD), and ischemic heart disease (IHD) mortality rates in adults in the counties of the state of Rio de Janeiro (SRJ), from 1979 to 2010. Methods: The counties of the SRJ were analysed according to their denominations stablished by the geopolitical structure of 1950, Each new county that have since been created, splitting from their original county, was grouped according to their former origin. Population Data were obtained from the Brazilian Institute of Geography and Statistics (IBGE), and data on deaths were obtained from DataSus/MS. Mean CVD, CBVD, and IHD mortality rates were estimated, compensated for deaths from ill-defined causes, and adjusted for age and sex using the direct method for three periods: 1979–1989, 1990–1999, and 2000–2010, Such results were spatially represented in maps. Tables were also constructed showing the mortality rates for each disease and year period. Results: There was a significant reduction in mortality rates across the three disease groups over the the three defined periods in all the county clusters analysed, Despite an initial mortality rate variation among the counties, it was observed a homogenization of such rates at the final period (2000–2010). The drop in CBVD mortality was greater than that in IHD mortality. Conclusion: Mortality due to CVD has steadily decreased in the SRJ in the last three decades. This reduction cannot be explained by greater access to high technology procedures or better control of cardiovascular risk factors as these facts have not occurred or happened in low proportion of cases with the exception of smoking which has decreased significantly. Therefore, it is necessary to seek explanations for this decrease, which may be related to improvements in the socioeconomic conditions of the population.

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Fecundity is one of the most important parameters in studying the reproductive output of Pleocyemata decapods, especially because of its relationship to the efficiency of population replacement. Knowledge of fecundity provides basic elements for understanding the reproductive strategies, dynamics, and evolution of a given population. The present investigation provides informations on fecundity, egg size, egg loss, and the relationship between fecundity and selected environmental features, for the spider crab Mithraculus forceps (A. Milne Edwards, 1875). Ovigerous crabs were collected each month during 2000, by SCUBA diving, at Couves Island (23º25'25"S, 44º52'03"W) on the northeastern coast of the state of São Paulo, Brazil. A total of 40 ovigerous females with egg in early development (initial stage) and 28 final stage eggs were obtained and analyzed. Mean fecundity, from eggs of the initial stage, was 402.8 ± 240.1 eggs, ranging from 60 to 1,123 eggs. Sizes of females ranged from 9.4 to 14.0 mm carapace width. Mean egg size was 0.56 ± 0.06 mm diameter. A 20.33% rate of egg loss was estimated by comparing the fecundities of batches of eggs in early and late development (40 initial batches and 28 final stages batches). There were no significant relationships between the water temperature or salinity and variations in fecundity. As in most brachyuran species, M. forceps showed a strong conservative relationship between fecundity and body size.

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Poultry meat and its derivatives are among the foodstuffs considered by environmental health authorities to present the highest risks to the public. A total of 185 samples were collected in five monthly batches, from different processing stages in a sausage plant that uses mechanically-deboned chicken meat (MDCM), and testedfor the presence of Salmonella. Enrichment was carried out in both Kauffman's tetrathionate broth and Rappaport-Vassiliadis broth and isolation on Salmonella-Shigella agar and brilliant-green agar. Live Salmonella bacteria were isolated from six samples of the raw meat and from the emulsion, in batches three, four, and five, but not from any sample in batches one or two. The six isolated strains were all classified as Salmonella Albany, which has not previously been reported in MDCM. Of the two enrichment broths, Rappaport-Vassiliadis gave the better results. The pattern of contamination suggests a probable common source, given that a new supplier was used in the third, fourth, and fifth months. It was also shown that the industrial cooking was effective in preventing Salmonella surviving in the final product.

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The aim of this work is to establish a relationship between schistosomiasis prevalence and social-environmental variables, in the state of Minas Gerais, Brazil, through multiple linear regression. The final regression model was established, after a variables selection phase, with a set of spatial variables which contains the summer minimum temperature, human development index, and vegetation type variables. Based on this model, a schistosomiasis risk map was built for Minas Gerais.

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Since the discovery of Trypanosoma cruzi and the brilliant description of the then-referred to "new tripanosomiasis" by Carlos Chagas 100 years ago, a great deal of scientific effort and curiosity has been devoted to understanding how this parasite invades and colonises mammalian host cells. This is a key step in the survival of the parasite within the vertebrate host, and although much has been learned over this century, differences in strains or isolates used by different laboratories may have led to conclusions that are not as universal as originally interpreted. Molecular genotyping of the CL-Brener clone confirmed a genetic heterogeneity in the parasite that had been detected previously by other techniques, including zymodeme or schizodeme (kDNA) analysis. T. cruzi can be grouped into at least two major phylogenetic lineages: T. cruzi I, mostly associated with the sylvatic cycle and T. cruzi II, linked to human disease; however, a third lineage, T. cruziIII, has also been proposed. Hybrid isolates, such as the CL-Brener clone, which was chosen for sequencing the genome of the parasite (Elias et al. 2005, El Sayed et al. 2005a), have also been identified. The parasite must be able to invade cells in the mammalian host, and many studies have implicated the flagellated trypomastigotes as the main actor in this process. Several surface components of parasites and some of the host cell receptors with which they interact have been described. Herein, we have attempted to identify milestones in the history of understanding T. cruzi- host cell interactions. Different infective forms of T. cruzi have displayed unexpected requirements for the parasite to attach to the host cell, enter it, and translocate between the parasitophorous vacuole to its final cytoplasmic destination. It is noteworthy that some of the mechanisms originally proposed to be broad in function turned out not to be universal, and multiple interactions involving different repertoires of molecules seem to act in concert to give rise to a rather complex interplay of signalling cascades involving both parasite and cellular components.

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Geographical information systems (GIS) are tools that have been recently tested for improving our understanding of the spatial distribution of disease. The objective of this paper was to further develop the GIS technology to model and control schistosomiasis using environmental, social, biological and remote-sensing variables. A final regression model (R² = 0.39) was established, after a variable selection phase, with a set of spatial variables including the presence or absence of Biomphalaria glabrata, winter enhanced vegetation index, summer minimum temperature and percentage of houses with water coming from a spring or well. A regional model was also developed by splitting the state of Minas Gerais (MG) into four regions and establishing a linear regression model for each of the four regions: 1 (R² = 0.97), 2 (R² = 0.60), 3 (R² = 0.63) and 4 (R² = 0.76). Based on these models, a schistosomiasis risk map was built for MG. In this paper, geostatistics was also used to make inferences about the presence of Biomphalaria spp. The result was a map of species and risk areas. The obtained risk map permits the association of uncertainties, which can be used to qualify the inferences and it can be thought of as an auxiliary tool for public health strategies.

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The experiment was conducted throughout the year 2005, at the Universidade Federal de Pelotas campus. The objectives of the study were to analyze the decomposition of rabbit (Oryctolagus cunniculus L.) with mean weight 2.67 Kg carcass and describe the interaction of insects acting on it, as well as the insect's potential use in legal medicine. We collected 5.239 insect specimens; 1.827 of them were obtained from larvae collected from carcasses and reared. The specimens were identified and 20 species were of forensic importance. The species Lucilia eximia (Wiedemann, 1819) and Chrysomya albiceps (Wiedemann, 1819) (Diptera, Calliphoridae) were better indicators of post-mortem interval (PMI) because they occurred in all seasons and were the first to reach the carcass. Hemilucilia semidiaphana (Rondani, 1850), H. segmentaria (Fabricius, 1805) (Diptera, Calliphoridae), Muscina stabulans (Fallén, 1817) and Synthesiomyia nudiseta (Wulp, 1883) (Diptera, Muscidae) can disclose death time because they occur only in certain months of the year. Oxyletrum discicolle (Brullé, 1840) (Coleoptera, Silphidae) and Dermestes maculates De Geer, 1774 (Coleoptera, Desmestidae) were found in advanced stages of decomposition.