1000 resultados para Clarke County (Va.)
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In the present work the life cycle of Psammolestes tertius was studied. The mean length, in days, fromeach stage was: 26.3 (± 1.7) (1st), 28.6 (± 1.8) (2nd), 28.4 (± 1.8) (3rd), 32.2 (± 1.9) (4th) and 33.5 (± 5.8) (5th). The mean egg incubation period was 15.7 days (± 1.7). Overall mortality was 48.9% and egg viability was 65.7%.
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In August 1983,85 inhabitants of the municipality of Humaitá, Amazonas State, Brazil were studied to determine the prevalence of antigens to HLA-A, -B, -C and DR. Thirty-eight were sick with malaria due to Plasmodium falciparum. All subjects were examined for splenomegaly, blood parasitaemia and antibodies to malaria. They constituted three groups: 1) 25 subjects native to the Amazon region who had never had malaria; 2) 38 Amazonian subjects who had malaria in the past or currently had an infection; 3) 22 patients with malaria who had acquired the infection in the Amazon Region but came from other regions of Brazil. Blood was taken from each person, the lymphocytes were separated and typed by the test of microlymphocytotoxicity. There was a high frequency of antigens that could not be identified in the groups studied which suggests the existence of a homozygote or phenotype not identified in the population. There was a high frequency of the phenotype Ag(W24) (44.7%) in group 2 when compared with group 1 (32%) or group 3 (9%). Also the individuals in group 2 showed an elevated frequency of antigen DR(4)80%) when compared with group 1 (36.6%) or group 3 (16.6%). These observations suggest the possibility of a genetic susceptibility to malaria among Amazonian residents and indicate a necessity for more extensive studies of the frequency of HLA antigens among inhabitants of this endemic malarial zone.
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A total of 207 patients with malaria caused by Plasmodium falciparum were submitted to 5 different treatment schedules with clindamycin from 1981 to 1984: A - 89 patients were treated intravenously and orally, or intramuscularly and orally with 20 mg/kg/day divided into two daily applications for 5 to 7 days; B-40 patients were treated orally with 20 mg/kg/day divided into two daily doses for 5 to 7 days; C-27 patients were treated with 20 mg/kg/day intravenously or orally divided into two daily applications for 3 days; D-16 patients were treated orally and/or intravenously with a single daily dose of 20 to 40 mg/kg/day for 5 to 7 days; E-35 patients were treated orally with 5 mg/kg/day divided into two doses for 5 days. Patients were examined daily during treatment and reexamined on the 7th, 24th, 21st, 28th and 35th day both clinically and parasitologically (blood test). Eighty three (40.1%) had moderate or severe malaria, and 97 (46.8%) had shown resistance to chloroquine or to the combination ofsulfadoxin and pyrimethamine. The proportion of cured patients was higher than 95% among patients submitted to schedules A and B. Side effects were only occasional and of low intensity. Three deaths occurred (1.4%), two of them involving patients whose signs and symptoms were already very severe when treatment was started. Thus, clindamycin proved to be very useful in the treatment of patients with malaria caused by Plasmodium falciparum and we recommend schedule A for moderate and severe cases and Bfor initial cases.
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Nos sistemas de geração, transmissão e distribuição de energia, os transformadores de potência são um dos componentes mais comuns e importantes. Deste modo, o desempenho dos transformadores é fundamental para a eficiência global dos sistemas. Para optimizar a eficiência dos transformadores, a escolha do material ferromagnético a usar para a construção do núcleo, é um factor muito importante. Por exemplo, o uso de um material ferromagnético amorfo no núcleo de um transformador, em vez de aço silício, reduz as perdas magnéticas totais do dispositivo. Outra possível solução para aumentar a eficiência dos sistemas de distribuição de energia, é a instalação de transformadores supercondutores de alta temperatura (SAT), normalmente arrefecidos em azoto líquido a 77 K. Deste modo, um transformador de 562,5 VA com núcleo de ferro amorfo foi projectado e construído e as suas propriedades magnéticas mais importantes foram medidas à temperatura ambiente, e à temperatura criogénica para deste modo contribuir para uma melhoria da eficiência dos transformadores supercondutores. De seguida, foram comparadas com as propriedades magnéticas de um transformador com núcleo de aço silício de grão orientado. As perdas magnéticas totais do material amorfo à temperatura ambiente e criogénica, os parâmetros do esquema equivalente de Steinmetz e a impedância de curto-circuito são apresentadas e discutidas. Foi também caracterizado o comportamento do transformador em carga determinando, por exemplo, o rendimento e a regulação da tensão em função da carga do transformador. Aspectos de construção do transformador são também abordados.
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INTRODUCTION: In recent years, hantavirus infections producing severe diseases have obtained an increased attention from public health authorities from the countries of Eurasia to the Americas. Brazil has reported 1,300 cases of hantavirus cardiopulmonary syndrome (HCPS) from 1993 to 2010, with about 80 of them occurring in the northeast of the State of São Paulo, with 48% fatality rate. Araraquara virus was the causative agent of HCPS in the region. Considering that hantaviruses causing human disease in the Americas were unknown until 1993, we have looked for hantavirus infections in the population of Cássia dos Coqueiros county, northeast of the State of São Paulo, Brazil, before this time. This county has about 2,800 inhabitants and an economy based on agriculture, including cultivation of Brachiaria decumbens grass. The grass seeds are an important rodent attraction, facilitating transmission of hantavirus to man. Four HCPS cases were reported so far in the county. METHODS: In this study, 1,876 sera collected from 1987 to 1990 were tested for IgG to hantavirus by IgG-ELISA, using the N recombinant protein of Araraquara virus as antigen. RESULTS: Positive results were observed in 89 (4.7%) samples, which were all collected in 1987. The positivity among urban inhabitants was 5.3%, compared with 4.3% among those living in rural areas. CONCLUSIONS: Our results showed that hantavirus infections occurred in Cássia dos Coqueiros, completely unrecognized, even before hantaviruses were described in the Americas.
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Many potentially harmful pesticides for both human health and the environment are used in Brazilian Amazon. However, no scientific datum on pesticide usage is presently available for this region. Consequently, it is difficult to assess which substances arc used and in which quantities. As an important premise for future work on pesticide contamination in the county of Santarém (State of Pará, Brazil), a survey was conducted in order to qualify and quantify the use of some pesticides in this region. This investigation was made between January and March 1997 and August and October 1998 and revealed use of several organophosphates, synthetic pyrethroids and carbamates insecticides. Furthermore, many herbicides and fungicides were listed. These pesticides are used for agriculture, domestic, and sanitary programs. This paper also provides a first estimation of quantities of some insecticides commonly used in agriculture (chlorpyrifos, malathion, metamidophos and methyl-parathion). The annual consumption for these four compounds is estimated at ca. 1 910 kg. Organophosphate insecticide consumption in the county of Santarém seems to be lower than the Brazilian average in terms of «per capita» and «per agricultural area» consumptions. Nevertheless, this county uses toxic substances on sensitive environments such as floodplains (várzeas), making relevant a thorough study on the potential contamination of this environment and its biota.
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Na Amazônia, a regeneração natural da floresta em pastos e cultivos abandonados pode ser afetada pelas saúvas, pois estas são importantes predadoras das plântulas e das sementes das espécies arbóreas que eventualmente ali se estabelecem. Entretanto, pouco se sabe sobre como as chances de uma dada planta ser atacada ou de uma semente ser removida pelas saúvas varia no tempo e no espaço. Com este intuito, estabeleci uma parcela de 80 χ 120 m, subdividida em quadrantes de 10 χ 10m, em um campo abandonado próximo a Manaus. Na periferia desta parcela haviam 3 ninhos da saúva Atta laevigata. Ao longo de 1 ano, determinei quais plantas (das espécies arbóreas somente) foram atacadas pelas formigas. Determinei também como variou a atividade de coleta de sementes por A. laevigata. Para isto utilizei grãos de feijão (Phaseolus vulgaris). Iscas, com cerca de 20 feijões cada, foram distribuídas pela parcela ao longo do ano. Finalmente, determinei se plantas (mudas de Bellucia imperialis) estabelecidas em solo desnudo tinham uma maior chance de serem atacadas do que aquelas estabelecidas em solo com cobertura de gramíneas. Os resultados mostram que a atividade de coleta de sementes foi espacialmente agregada. A maior atividade foi observada nas regiões sudeste e noroeste da parcela, em geral, próximo aos ninhos. Forte variação temporal na coleta de sementes também foi observada. O pico máximo de atividade ocorreu em meados de julho e o de menor atividade em meados de janeiro. A atividade de corte seguiu um padrão similar. Houve uma clara diminuição no número de plantas atacadas entre novembro e janeiro. A proporção de plantas atacadas por parcela variou entre 6 e 89%. A incidência de ataques por saúvas sobre mudas de B. imperialis não variou em função da cobertura vegetal (com ou sem gramíneas). Isto possivelmente em função da forte heterogeneidade espacial na atividade de A. laevigata, que encobriu qualquer efeito devido a cobertura vegetal.
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La Esclerosis Múltiple es una de las enfermedades autoinmunes del Sistema Nervioso Central más frecuentes en adultos jóvenes. Un modelo experimental de la misma es la Encefalomielitis Autoinmune Experimental (EAE). Numerosos trabajos demuestran que en EAE, los clones patogénicos capaces de transferir la enfermedad son células T cooperadoras tipo 1 (Th1), mientras que las células T cooperadoras tipo 2 (Th2) actuarían como clones protectivos. Debido a las funciones opuestas de estas dos poblaciones existe la posibilidad de que la desregulación inmune asociada a Esclerosis Múltiple y su modelo experimental EAE se relacione a un desbalance Th1-Th2. La célula presentadora de antígeno (CPA), la dosis de antígeno, su ruta de entrada, el tipo de interleuquina presente en el medio, las moléculas co-estimulatorias de la CPA, etc., son fundamentales para la inducción de poblaciones Th1 ó Th2. Las estrategias terapéuticas actuales intentan suprimir la enfermedad administrando el autoantígeno por distintas vías, como por ejemplo la vía oral, intragástrica, endovenosa, etc. La inducción de tolerancia utilizando la vía intraperitoneal (ip) no ha sido muy explorada. Recientemente hemos iniciado una nueva línea de trabajo en la cual se suprimió la EAE inyectando i.p. antígenos de mielina en días previos a la inmunización. El objetivo de este proyecto será estudiar la vía i.p. y las CPA peritoneales en la inducción de supresión de la EAE. Se analizará: 1) El mecanismo inmunológico por el cual se induce supresión al inyectar antígenos de mielina por la vía i.p., estudiando si en los animales suprimidos se genera un estado de anergia al autoantígeno y/o células capaces de regular negativamente la respuesta autoinmune. 2) Si las CPA peritoneales pulsadas in vivo con antígenos de mielina al ser transferidas a animales receptores singénicos en días previos a la inmunización con mielina bovina son capaces de inducir supresión de la respuesta autoinmune en los animales receptores. 3) El fenotipo de las CPA peritoneales ya que se sabe que CPA que expresen determinadas moléculas de superficie tales como antígenos del Complejo Mayor de Histocompatibilidad, moléculas de adhesión, moléculas coestimulatorias, etc., participan activamente en el destino final de la respuesta inducida.
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Trypanosoma cruzi es el agente causal de la enfermedad de Chagas, un problema de salud importante en América Latina, así como también en América Central, ya que causa infección crónica afectando a millones de personas [1]. Durante esta enfermedad se han descripto varias alteraciones de la respuesta inmune, entre ellas una severa inmunosupresión durante la etapa aguda de la infección, tanto en humanos como en ratones. Células T provenientes de ratones infectados activadas in vitro, muestran reducción en la respuesta proliferativa a mitógenos, característica de un estado de inmunosupresión [2-4]. La falla del sistema inmune durante estadios tempranos de la infección probablemente colabore con la diseminación y el establecimiento del parásito. Un gran número de estudios se han focalizado en la identificación de mecanismos moleculares responsables del fenómeno de inmunosupresión, entre los mecanismos citados se ha demostrado presencia de células supresoras [5-9], factores inmunosupresores presentes en el parásito [2, 3, 10-13], producción excesiva de óxido nítrico [14], disminuida producción de IL-2 y reducida expresión del receptor de IL2 en células de bazo de animales infectados [9, 15-17]. Muchos de estos mecanismos han sido exhaustivamente investigados, sin embargo no está del todo claro si existen mecanismos adicionales involucrados en la inmunosupresión de la célula T. Adicionalmente, en los últimos años nuevas moléculas que median la regulación negativa de la célula T, entre las cuales están PD-1/PD1-L [18], arginasa [19] y E3 ubiquitina ligasas [20-22], han sido reportadas durante inmunosupresión en diversas infecciones. Trypanosoma cruzi, the etiological agent of Chagas’ disease, is parasite causing chronic infections in human and other mammalian species. There is an important immunosupresion during the acute phase of the infection that contribute to the dissemination and installation of the parasite. Several studies have been focused on identifying the mechanisms involved in the immunosupresion; however it is not clear if there are additional mechanisms implicated. In addition, during the last years new molecules involved in the negative T cell regulation such as PD-1/PD1-L pathway and E3 ubiquitin ligases (E3-Ub-Lig) have been reported. It has been demonstrated, that E3-Ub-Lig control the amount and localization of intracellular signal mediators, limiting T cell activation. Moreover, these mechanisms mediate the immunosupresion observed during several infections leading to the persistence of the pathogen in the host. In this project the role of E3-Ub-Lig on the T cell immunosupresion and hipo-response mechanisms observed during T. cruzi infection will be studied. On the other hand, it has been reported that some pathogens release proteins with E3-Ub-Lig activity modifying the ubiquitination process to promote their survival and replication in the host. Recently, a protein with E3-Ub-Lig activity was identified in T. cruzi, however its target molecule has not been discovered yet. Therefore, one of the aims of this project consists on studying different potential target molecules for this novel E3-Ub-Lig. In addition, during the last years, important progress has been done about the biological rol of PD-1/PD1-L pathway on the regulation of the immune response in several infections. However, it is not well known how PD-1/PD1-L pathway transduces signals at intracelular level to block T cell response. Because of this, it is interesting to study if there is any relation between the PD-1/PD1-L pathway and E3-Ub-Lig on the mechanism of T cell immunosupression during T. cruzi infection.
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Introducción: Existen evidencias epidemiológicas, funcionales y patológicas que vinculan las vías aéreas superior e inferior, reconocidas clínicamente como una vía aérea única. Objetivos: 1.Estudiar la enfermedad alérgica en la vía aérea. 2. Investigar el impacto pulmonar de la enfermedad de la vía aérea superior. 3. Comparar el efecto bronquial de la enfermedad de la vía aérea superior de etiología alérgica y no alérgica. Población y métodos: Estudio prospectivo, observacional, descriptivo y analítico. Se incluirán niños y adolescentes entre 6 y 18 años con síntomas de rinitis alérgica y no alérgica de diferentes grados de gravedad clínica, sin asma. Se establecerá por historia clínica, edad, sexo, índice de masa corporal y duración de la rinitis. Se realizarán pruebas cutáneas con aeroalergenos, espirometría por curva flujo-volumen y estudio de citología nasal, dosaje de inmunoglobulinas. Se calculará un tamaño muestral mínimo con un poder de 80%, una confianza de 95% y una precisión de 10%, para una prevalencia estimada de rinitis pura de 30% en 150 sujetos, aplicando la fórmula n=Zα2 p(1-p)/i2. Se realizará un muestreo no aleatorio sucesivo. Resultados esperados: La rinitis produciría alteraciones subclínicas en los parámetros de funcionalidad pulmonar. Dicho impacto podría variar de acuerdo al grado clínico de rinitis y su etiología. Utilidad potencial de los resultados: Profundizar el conocimiento de la fisiología de la vía aérea como una unidad y detectar el posible impacto funcional de la rinitis sobre la vía aérea inferior y sus potenciales implicancias terapéuticas.
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Sustainable Development requires appropriate and continuous planning and management of economic, socio cultural and environmental resources. Tourism planning calls for continuous collaboration among tourism agencies, local authorities and local communities for success of the industry. While evidence suggests that tourism planning has been extensively documented, it is apparent that Donegal and Sligo County Councils have, in some cases failed to adequately address the significance of planning of the tourism industry for the North West of Ireland. This was investigated through interviews with chief planners of Donegal and Sligo county councils and was conducted in conjunction with the analysis of county development plans; which were formulated by both organisations involved in this study. Evidence suggests that although tourism is extensively documented by Donegal and Sligo county councils, neither of the two local authorities have developed implementation strategies to facilitate the promotion of sustainable tourism development. This research compares and analyses Donegal and Sligo county councils and how they plan for sustainable tourism development. It outlines the role of the county councils in relation to tourism planning and how Donegal and Sligo compare in how they plan for such a significant industry in the North West o f Ireland. It highlights the importance of implementation tools and methods and offers future directions that can assist in the development of sustainable tourism.
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The aim of the project was to determine the extent and quality of the groundwater in Tipperary South Riding with a view to developing a groundwater protection plan which would allow the Local Authority to manage, protect and develop the groundwater as efficiently as possible. The geology of the area varies with topography. The low-lying areas of the county comprise mainly Carboniferous limestones while the elevated regions consist of sandstones and shales of Upper Carboniferous, Devonian and Silurian ages. Deformation of these rocks decreases in magnitude moving northwards over the area; the Southern Synclines having suffered the effects of the Hercynian orogeny and the northern region exhibiting Caledonian orogenic trends. Quaternary (subsoil) deposits are found throughout the area and are of variable thickness and permeability. Till is the most widespread deposit with discontinuous pockets of sand and gravel in various proportions, and some marl, alluvium and peat in places. The principal aquifers of the area are the Kiltorcan sandstone formation and various limestone units within the Carboniferous succession. 50 % of south Tipperary constitutes either regionally or locally important aquifers. Secondary permeabilities created by structural deformation, dolomitisation, karstification and weathering processes create high transmissivities and often have large well yields. Specific baseflow analysis highlighted the complexity of the aquifers and proved that the lower part of the Suir river system is a major groundwater resource region. The hydrochemistry and water quality of the local authority groundwater sources was examined briefly. The majority of south Tipperary is underlain by limestone or Quaternary deposits derived from limestone and, consequently, calcium/magnesium bicarbonate waters predominate. The quality of the groundwater in south Tipperary demonstrates that the main concern originates from the presence of E.coli, and Total coliforms. The primary sources of contamination are from farmyard wastes and septic tanks. The vulnerability of groundwater to diffuse and point sources of pollution has been found to be dependent on the overlying soil, subsoil and the thickness of the unsaturated zone. A conceptual rather than quantitative approach is used and it is found that approximately 60% of south Tipperary is designated as being extremely or highly vulnerable. The groundwater protection plan was devised subsequent to an understanding of the aquifer systems, an assessment of the vulnerability, and a review of the Irish planning system and environmental law. It is recommended that the plan be integrated into the county development plan for legislative purposes. A series of acceptability matrices were devised to restrict potentially polluting activities in vulnerable areas while maintaining a balance between protection of the groundwater resource and the need to site essential developments.
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This thesis details the findings of a study into the spatial distribution and speciation of 238U, 226Ra and 228Ra in the soils of the Cronamuck valley, County Donegal . The region lies on the north-eastern edge of the Barnesmore granite and has been the subject of uranium prospecting efforts in the past. The results of the project provide information on the practicability of geostatistical techniques as a means of estimating the spatial distribution of natural radionuclides and provide insight into the behaviour of these nuclides and their modes of occurrence and enrichment in an upland bog environment. The results of the geostatistical survey conducted on the area indicate that the primary control over the levels of the studied nuclides in the soil of the valley is the underlying geology. Isopleth maps of nuclide levels in the valley indicate a predominance of elevated nuclide levels in the samples drawn from the granite region, statistical analysis of the data indicating that levels of the nuclides in samples drawn from the granite are greater than levels drawn from the non-granite region by up to a factor of 4.6 for 238U and 4.9 for 226Ra. Redistribution of the nuclides occurs via drainage systems within the valley, this process being responsible for transport of nuclides away from the granite region resulting in enrichment of nuclides in soils not underlain by the granite. Distribution of the nuclides within the valley is erratic, the effect of drainage f lows on the nuclides resulting in localized enriched areas within the valley. Speciation of the nuclides within one of the enriched areas encountered in the study indicates that enrichment is as a result of saturation of the soil with drainage water containing trace amounts of radionuclides. 238U is primarily held within the labile fractions (exchangeable cat ions + easily oxidisable organics + amorphous iron oxides ) of the soil , 226Ra being associated with the non- labile fractions, most probably the resistant organic material. 228Ra displays a significant occurrence in both the labile and non- labile fractions. The ability of the soil to retain uranium appears to be affected largely by the redox status of the soil, samples drawn from oxidizing environments tending to have little or no uranium in the easily oxidisable and amorphous iron oxide fractions. This loss of uranium from oxidised soil samples is responsible for the elevated 226Ra /238U disequilibrium encountered in the enriched areas of the valley. Analysis of the data indicates that samples displaying elevated 226Ra/238U ratios also exhibit elevated 228Ra/238U ratios indicating a loss of uranium from the samples as opposed to an enrichment of 226Ra.
Resumo:
Sándor Vajna; André Jordan; Konstantin Kittel