983 resultados para PERIVASCULAR DRAINAGE


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Dermatite tem sido observada em bovinos no Uruguai e no Rio Grande do Sul que são suplementados com farelo de arroz desengordurado em quantidade equivalente a 1% do peso corporal. Descreve-se um surto de dermatite associada ao consumo de farelo de arroz desengordurado em um município do interior do Rio Grande do Sul. Do total de 26 bovinos, com três anos de idade, sete apresentaram lesões que foram observadas após 24 dias de ingestão da ração de farelo de arroz desengordurado. As lesões eram observadas na extremidade distal dos membros posteriores e se caracterizavam por áreas de alopecia, com acentuado espessamento da epiderme, formando crostas secas, espessas e fissuradas. A lesão histológica observada nestes casos foi caracterizada como dermatite perivascular superficial crônica focalmente extensa moderada, com acantose irregular e formação de crosta serocelular. As lesões macro e microscópicas observadas, juntamente com os dados epidemiológicos, permitem concluir o diagnóstico de dermatite associada ao consumo de farelo de arroz desengordurado. As lesões histológicas, embora não patognomônicas, são descritas nesta doença.

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Acid mine drainage (AMD) presents a serious problem for the environment for the massive formation of acidic leachates containing heavy metals. The present work deals with the AMD treatment using neutralizing limestone side-products. The conventional methods for prevention, mitigating and control of AMD formation are described. The experimental testing of Nordkalk Oy calcite-containing side-stones for acid neutralizing and removal of nickel from solutions presents the research objective. The batch experiments in acid neutralizing with subsequent metal content analysis were carried out. The results showed the dependence of pH on the dose of neutralizing material and the exposure time. The nickel removal, unlike iron, within the pH range from 1.2 to 6.0 appeared to be inadequate. The further research on nickel co-precipitation with iron and aluminium may appear to be necessary together with testing of alkalinity strengthening materials.

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Cases of vesicular and exanthematic disease by Vaccinia virus (VACV) have been reported in dairy herds of several Brazilian regions, occasionally also affecting humans. The present article describes eight outbreaks of vesicular disease caused by VACV in dairy herds of six counties of Goiás state, Midwestern Brazil (2010-2012), involving a total of 122 cows, 12 calves and 11 people. Dairy cows (3 to 9 years old) were affected in all cases and calves (2 to 9 months old) were affected in five outbreaks, presenting oral lesions. The morbidity ranged between 8 and 100% in cows, and 1.5 to 31% in calves. In the cows, the clinical signs started with vesicles (2-7mm), painful and coalescent papules (3-8 mm), which resulted in ulcers (5-25mm) and scabs in teats, and, occasionally, in the muzzle. The clinical course lasted from 16 to 26 days. The histopathology of bovine skin samples revealed superficial perivascular inflammatory infiltrate of lymphocytes, plasma cells, neutrophils, macrophages and multifocal areas of acanthosis, spongiosis, hipergranulosis and parakeratotic or orthokeratotic hyperkeratosis with adjacent focally extensive ulcers. Eosinophilic inclusion bodies were noted in the cytoplasm of the keratinocytes. PCR to vgf gene of Orthopoxvirus was positive in samples collected from all outbreaks, and in some cases, genomic VACV sequences were identified by nucleotide sequencing of the PCR amplicons. Infectious virus was isolated in cell culture from scabs from one outbreak. Antibodies to Orthopoxvirus were detected in at least 3 or 4 animals in most outbreaks, by ELISA (outbreaks 1, 2, 3, 4, 5 and 7) or virus-neutralization (outbreak 6). Neutralizing titers ranging from 8 to 64 in outbreak 6. In all outbreaks, VACV infection was suspected based on the clinical and pathological findings and it was confirmed by laboratory tests. Upon the etiological confirmation, other agents associated with vesicular disease were discarded. In all outbreaks, at least one milker who handled the affected cows developed malaise, headache, fever, painful vesico-pustular lesions mainly in the hands, but also in the neck and nose. These results confirm the circulation of VACV in the region and call attention for a correct diagnosis and the adoption of prophylactic and control measures.

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O presente trabalho relata um surto de intoxicação por sal em ovinos no Brasil, em uma propriedade no estado do Pará. De um total de 545 ovinos, oito animais adoeceram (1,46%) e quatro destes morreram (50%). A avaliação das instalações e do manejo indicaram como fatores predisponentes a ingestão excessiva de mistura mineral e a restrição hídrica. Os principais sinais clínicos foram decúbito, diminuição ou ausência da sensibilidade cutânea, ausência dos reflexos de ameaça, palpebral e auricular, midríase, nistagmo, opistótono, espasticidade de membros, sonolência e estupor. Havia ainda, timpanismo, diarreia, taquipneia, taquicardia, desidratação e poliúria. A evolução do quadro clínico nos animais que morreram variou de duas horas e meia a 48 horas. As médias das concentrações séricas de sódio e de potássio de 31 ovinos do mesmo lote afetado pela intoxicação, em amostras colhidas durante o surto, revelaram hipernatremia (190mEq/l) e hipercalemia (8,2mEq/l). À necropsia, observou-se em um animal, achatamento das circunvoluções cerebrais. Microscopicamente, neste animal, evidenciou-se vacuolização moderada do neurópilo, particularmente nas lâminas intermediárias do córtex cerebral, com aumento dos espaços perineural e perivascular. Nessas áreas foram observados ainda, acentuada tumefação e edema dos astrócitos e necrose neuronal aguda. A dosagem de sódio no encéfalo de um ovino, revelou-se elevada com valor de 3.513ppm. O diagnóstico foi realizado com base na epidemiologia, nos sinais clínicos, nas lesões macro e microscópicas e nas dosagens de sódio no soro e no encéfalo dos ovinos.

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Different methods for lymphatic mapping in dogs, such as infusing tissues with vital dyes or radioactive substances, have been studied, aiming at the early detection of lymph node metastasis. Thus, one could anticipate therapeutic measures and, consequently, prolong the survival and improve the quality of life of the patients. The objectives of this experiment were to locate the nodes responsible for draining the uterine body and horns and to try to establish the relationship between the uterus and the medial iliac lymph nodes to contribute to the early diagnosis and prognosis of uterine disorders. We studied 15 female dogs divided into two groups (5 dead and 10 intraoperative ovariohysterectomy bitches). The dye used was patent blue V (Patent Bleu V®). It was observed that the iliac lymph node chain receives much of the uterine (horns) drainage. This method should be considered for safer studies of uterine sanity. This information suggests that evaluating these lymph nodes will allow correlating changes in their physiological status with uterine pathologies.

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O presente trabalho foi conduzido com o objetivo de relatar surtos de fotossensibilização causados por Froelichia humboldtiana em equídeos no Estado do Rio Grande do Norte, Brasil. Foram examinados animais de três propriedades rurais, além de asininos abandonados nas estradas. Procedeu-se a coleta de amostras de sangue periférico de cinco jumentos e dois equinos para análise das atividades das enzimas hepáticas e concentrações de bilirrubina total, direta e indireta. Das áreas de pele com lesões de dois jumentos e de um equino foram realizadas biópsias. Constatou-se que 50 asininos, 18 equinos e duas mulas foram acometidos. Dos asininos acometidos, 45 eram jumentos criados soltos em margens de estradas. Relatou-se a morte de 30 jumentos em decorrência de miíases e debilidade. Os animais tinham histórico de apresentarem lesões de fotodermatite aproximadamente um mês após pastarem em áreas invadidas por F. humboldtiana e recuperavam-se das lesões 10 a 30 dias após serem retirados dessas áreas. Porém, o quadro de prurido e automutilação retornava em uma ou duas semanas quando os equídeos eram reintroduzidos nessas áreas. Ao exame clínico de asininos jovens e adultos, foram observadas feridas extensas, ulceradas, que drenavam exsudato seroso abundante. Todas essas feridas decorriam de traumas causados por automutilação secundária ao intenso prurido. Além disso, muitas das feridas apresentavam miíase. Os equinos e as mulas apresentavam lesões de fotodermatite somente nas áreas de pele despigmentadas, não sendo observadas lesões oculares. A avaliação histopatológica de biópsias de pele revelou inflamação perivascular na derme superficial. Na epiderme havia extensas úlceras, recobertas por fibrina associada a infiltrado neutrofílico e numerosos agregados bacterianos basofílicos superficiais. As atividades séricas de AST, GGT e as concentrações de bilirrubina no soro estavam dentro dos valores de referência. O diagnóstico de fotossensibilização primária associada à ingestão de F. humboldtiana foi baseado na epidemiologia, sinais clínicos, bioquímica sérica, biópsia de pele e reocorrência das lesões após os animais serem reintroduzidos no pasto invadido pela planta. Conclui-se que a F. humboldtiana é uma importante causa de fotossensibilização primária em equídeos no semiárido brasileiro, resultando em quadro de debilidade e morte de grande número de animais, principalmente asininos que não recebem tratamento adequado.

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This thesis presents a set of methods and models for estimation of iron and slag flows in the blast furnace hearth and taphole. The main focus was put on predicting taphole flow patterns and estimating the effects of various taphole conditions on the drainage behavior of the blast furnace hearth. All models were based on a general understanding of the typical tap cycle of an industrial blast furnace. Some of the models were evaluated on short-term process data from the reference furnace. A computational fluid dynamics (CFD) model was built and applied to simulate the complicated hearth flows and thus to predict the regions of the hearth exerted to erosion under various operating conditions. Key boundary variables of the CFD model were provided by a simplified drainage model based on the first principles. By examining the evolutions of liquid outflow rates measured from the furnace studied, the drainage model was improved to include the effects of taphole diameter and length. The estimated slag delays showed good agreement with the observed ones. The liquid flows in the taphole were further studied using two different models and the results of both models indicated that it is more likely that separated flow of iron and slag occurs in the taphole when the liquid outflow rates are comparable during tapping. The drainage process was simulated with an integrated model based on an overall balance analysis: The high in-furnace overpressure can compensate for the resistances induced by the liquid flows in the hearth and through the taphole. Finally, a recently developed multiphase CFD model including interfacial forces between immiscible liquids was developed and both the actual iron-slag system and a water-oil system in laboratory scale were simulated. The model was demonstrated to be a useful tool for simulating hearth flows for gaining understanding of the complex phenomena in the drainage of the blast furnace.

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Depletion of high grade mineral resources, tightening of environmental regulations and the environmental impact of acid mine drainage caused by sulfidic minerals continuously increase the interest in processing tailings and other mine waste. Treating waste requires additional capital and operational input, but the decrease in size and need of tailings ponds and permits decrease the overall costs. Treatment and utilization of the tailings could also bring added revenue by the recovery of valuables. Leaching of metal sulfides is very demanding and time consuming and hence process conditions need to be carefully optimized. The leaching of sulfides is affected by for example the choice of leaching agent, its concentration and temperature, pH, the redox potential, pressure, pulp density and particle size distribution. With reference to the mine case study the leaching of nickel and copper sulfides, especially the primary minerals pentlandite and chalcopyrite were investigated. Leaching behavior and recoveries for nickel, copper and iron were found out by sulfuric and citric acid leaching experiments using tailings samples of high and low sulfur content. Moderate recoveries were obtained and citric acid seemed more attractive. Increase in temperature and decrease in pulp density had positive effect on the recovery and pH was also proven to have a significant effect on the recovery of valuables. The rate determining step was determined through kinetic modeling in case of all valuables separately. Leaching was controlled by diffusion. The investigated multimetal tailing showed moderate potential in recovering of metal valuables from low grade tailing deposits. The process conditions should however be further optimized.

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Com o objetivo de reconhecer caracteres vegetativos que auxiliem na identificação de Myrtaceae, foram estudadas as folhas de 17 espécies de Eugenia, presentes da bacia do Rio Tibagi, PR. Analisando os padrões de nervação das lâminas e as características da bainha perivascular, na região do pecíolo, foi possível separar essas espécies em três grupos distintos. O padrão camptódromo-broquidódromo ocorre em nove espécies; o acródromo em quatro espécies e, nas quatro restantes, observa-se um padrão misto. A bainha perivascular do pecíolo pode ser de natureza parenquimática, esclerenquimática ou mista. Elaborou-se uma chave de identificação usando esses caracteres vegetativos, demonstrando que eles podem, seguramente, auxiliar na identificação das espécies de Eugenia.

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Somatic embryogenesis was induced from cotyledon explants of eggplant cultured on MS medium supplemented with 54 µM NAA. Anatomical analysis of somatic embryo initiation and development was performed during the first four weeks. Proembryo formation was observed after the second day of culture, directly from perivascular cells or via pro-embryogenic masses derived from indeterminate meristematic masses (IMMs) originated in the vascular tissue. Those IMMs also gave rise to root primordia after 10 days of culture. The origin of embryos is discussed as well as the similarities between somatic embryogenesis and adventitious root formation.

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The acid mining drainage is considered the most significant environmental pollution problem around the world for the extensive formation acidic leachates containing heavy metals. Adsorption is widely used methods in water treatment due to it easy operation and the availability of a wide variety of commercial adsorbent (low cost). The primary goal of this thesis was to investigate the efficiency of neutralizing agents, CaCO3 and CaSiO3, and metal adsorption materials with unmodified limestone from Company Nordkalk Oy. In addition to this, the side materials of limestone mining were tested for iron adsorption from acidic model solution. This study was executed at Lappeenranta University of Technology, Finland. The work utilised fixed-bed adsorption column as the main equipment and large fluidized column. Atomic absorption spectroscopy (AAS) and x-ray diffraction (XRD) was used to determine ferric removal and the composition of material respectively. The results suggest a high potential for the studied materials to be used a low cost adsorbents in acid mine drainage treatment. From the two studied adsorbents, the FS material was more suitable than the Gotland material. Based on the findings, it is recommended that further studies might include detailed analysis of Gotland materials.

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We examined the relationships between environmental variations in lotic ecosystems with the seasonal dynamics of macroalgae communities at different spatial scales: drainage basin of two rivers (Rio das Pedras and Rio Marrecas), shading (open and shaded stream segments), mesohabitat (riffles and pools), and microhabitats. Data collections were made on a monthly basis between January and December/2007. A total of 16 taxa were encountered (13 species and 3 vegetative groups). All of the biotic parameters (richness, abundance, diversity, equitability, and dominance) were found to be highly variable at all of the spatial scales evaluated. On the other hand, abiotic variables demonstrated differences only at mesohabitat (in terms of current velocity) and shaded habitat (in terms of irradiance) scales. The seasonality of the macroalgae community structure was strongly influenced by microhabitat variables (current velocity, substrate H', and irradiance), demonstrating their importance over time and at different scales. Regional variables (temperature, oxygen saturation, specific conductance, pH, and turbidity) were found to have little influence on the temporal dynamics of the macroalgae communities evaluated.

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We examined the ecological distribution of macroalgal communities in streams using species groups (taxonomic units = algal phyla, and morphological = morphological types) with similar structures and functions instead of the species themselves. The study was conducted from June to July/2007 in two drainage basins located in mid-southern region of Paraná State , Brazil. Evaluations of macroalgal communities took into consideration the following spatial scales: the drainage basin (the Pedras river and Marrecas river basins), shading regime (open and shaded stream segments), mesohabitats (riffles and pools), and microhabitats (sampling units of 0.05m2). A total of 29 taxa (23 subgeneric, one generic, and five vegetative groups) were identified. On these, 12 taxa belong to Chlorophyta, 11 to Cyanobacteria, four to Heterokontophyta, and two to Rhodophyta. The proportions of morphological types were: 24% free filaments, 17.25% mats, tufts, gelatinous colonies, and gelatinous filaments, 7% crusts. In terms of spatial scales, we observed a predominance of Chlorophyta in open stream segments and Cyanobacteria in shaded stream segments, reflecting the loss of competitive advantage of green algae in sites with low energy availability. In the mesohabitats, the morphological types recorded in pools were predominantly poorly adapted to fast currents (free filaments), while those found in riffles (mats, tufts and gelatinous filaments) were highly resistant to fast water flows. As such, the use of species groupings based on algal taxonomy associated with morphological characteristics proved to be useful to understanding the distributions of these organisms in lotic environments.

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We present the results obtained with a ureterovesical implant after ipsilateral ureteral obstruction in the rat, suitable for the study of renal function after deobstruction in these animals. Thirty-seven male Wistar rats weighing 260 to 300 g were submitted to distal right ureteral ligation and divided into 3 groups, A (N = 13, 1 week of obstruction), B (N = 14, 2 weeks of obstruction) and C (N = 10, 3 weeks of obstruction). The animals were then submitted to ureterovesical implantation on the right side and nephrectomy on the left side. During the 4-week follow-up period serum levels of urea and creatinine were measured on the 2nd, 7th, 14th, 21st and 28th day and compared with preoperative levels. The ureterovesical implantation included a psoas hitch procedure and the ureter was pulled into the bladder using a transvesical suture. During the first week of the postoperative period 8 animals died, 4/13 in group A (1 week of obstruction) and 4/14 in group B (2 weeks of obstruction). When compared to preoperative serum levels, urea and creatinine showed a significant increase (P<0.05) on the 2nd postoperative day in groups A and B, with a gradual return to lower levels. However, the values in group B animals were higher than those in group A at the end of the follow-up. In group C, 2/10 animals (after 3 weeks of obstruction) were sacrificed at the time of ureterovesical implantation due to infection of the obstructed kidneys. The remaining animals in this group were operated upon but all of them died during the first week of follow-up due to renal failure. This technique of ureterovesical implantation in the rat provides effective drainage of the upper urinary tract, permitting the development of an experimental model for the study of long-term renal function after a period of ureteral obstruction

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The term urban heat island (UHI) refers to the common situation in which the city is warmer than its rural surroundings. In this dissertation, the local climate, and especially the UHI, of the coastal city of Turku (182,000 inh.), SW Finland, was studied in different spatial and temporal scales. The crucial aim was to sort out the urban, topographical and water body impact on temperatures at different seasons and times of the day. In addition, the impact of weather on spatiotemporal temperature differences was studied. The relative importance of environmental factors was estimated with different modelling approaches and a large number of explanatory variables with various spatial scales. The city centre is the warmest place in the Turku area. Temperature excess relative to the coldest sites, i.e. rural areas about 10 kilometers to the NE from the centre, is on average 2 °C. Occasionally, the UHI intensity can be even 10 °C. The UHI does not prevail continuously in the Turku area, but occasionally the city centre can be colder than its surroundings. Then the term urban cool island or urban cold island (UCI) is used. The UCI is most common in daytime in spring and in summer, whereas during winter the UHI prevails throughout the day. On average, the spatial temperature differences are largest in summer, whereas the single extreme values are often observed in winter. The seasonally varying sea temperature causes the shift of relatively warm areas towards the coast in autumn and inland in spring. In the long term, urban land use was concluded to be the most important factor causing spatial temperature differences in the Turku area. The impact was mainly a warming one. The impact of water bodies was emphasised in spring and autumn, when the water temperature was relatively cold and warm, respectively. The impact of topography was on average the weakest, and was seen mainly in proneness of relatively low-lying places for cold air drainage during night-time. During inversions, however, the impact of topography was emphasised, occasionally outperforming those of urban land use and water bodies.