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Relata-se um caso de lesão cutânea secundária à infecção por Corynebacterium pseudotuberculosis em bovino. Abscessos e múltiplas lesões cutâneas nodulares, variando de 8x10 para 20x25cm de diâmetro, firmes, sensíveis ao toque e sem mobilidade, algumas com superfície ulcerada, circundada por halo avermelhado e drenando secreção piossanguinolenta, e outras com superfícies alopécicas, foram identificados na região torácica lateral do animal. Exames histopatológicos e o isolamento do agente de fragmentos obtidos após remoção cirúrgica das lesões confirmaram tratar-se da forma cutânea da infecção pelo C. pseudotuberculosis. As lesões microscópicas caracterizaram-se por dermatite nodular piogranulomatosa e ulcerativa. A avaliação da susceptibilidade in vitro do C. pseudotuberculosis a antimicrobianos demonstrou que o agente era resistente à amicacina, kanamicina, neomicina e penicilina G, apresentando sensibilidade à ampicilina adicionada de subactam, amoxicilia com ácido clavulônico, cefalexina, cefalotina, cefotaxima, enrofloxacina, gentamicina e tetraciclina. A retirada cirúrgica das lesões e o tratamento com enrofloxacina resultaram na cura do animal. Lesões de pele observadas em casos de ptiose, carcinoma de células escamosas e na forma atípica da actinobacilose devem ser consideradas no diagnóstico diferencial da forma cutânea da infecção por C. pseudotuberculosis em bovinos. Os dados apresentados demonstram que a infecção pelo C. pseudotuberculosis deve ser considerada no diagnóstico diferencial das lesões de pele em bovinos no Brasil.(AU)

We report a case of secondary skin lesionby infection with Corynebacterium pseudotuberculosis in bovine. Abscesses and multiple nodular lesions, ranging from 8x10 to 20x25 cm in diameter, firm, sensitive to touch, and without mobility, some with ulcerated surface, surrounded by reddish halo and draining piosanguinolenta secretion, and other surfaces with alopecia, were identified in the skin of the animal`s thoracic area. Histopathology and isolation of the agent from fragments obtained after surgical removal of the lesions confirmed the cutaneous infection by C. pseudotuberculosis. Microscopic lesions were characterized by lumpy skin disease and ulcerative pyogranulomatous. Evaluation of in vitro susceptibility to antimicrobial demonstrated that the agent was resistant to amikacin, kanamycin, neomycin and penicillin G, and sensitive to ampicillin + subactam, amoxicilia with clavulonic acid, cephalexin, cephalothin, cefotaxime, enrofloxacin, gentamicin, and tetracycline. The surgical removal of the lesions, and treatment with enrofloxacin resulted in animal cure. Skin lesions observed in case of ptiose, squamous cell carcinoma and atypical form of Actinobacillosis should be considered in the differential diagnosis of cutaneous form of C. pseudotuberculosis infection in cattle. The data presented demonstrate that infection with C. pseudotuberculosis should be considered in the differential diagnosis of skin lesions in cattle in Brazil.(AU)

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In vehicle dynamics studies, the tire behaviour plays an important role in planar motion of the vehicle. Therefore, a correct representation of tire is a necessity. This paper describes a mathematical model for wheelchair tire based on the Magic Formula model. This model is widely used to represent forces and moments between the tire and the ground; however some experimental parameters must be determined. The purpose of this work is to identify the tire parameters for the wheelchair tire model, implementing them in a dynamic model of the wheelchair. For this, we developed an experimental test rig to measure the tires parameters for the lateral dynamics of a wheelchair. This dynamic model was made using a multi-body software and the wheelchair behaviour was analysed and discussed according to the tire parameters. The result of this work is one step further towards the understanding of wheelchair dynamics.

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In mechanical engineering, it is well established that contact between the tire and the ground is a key parameter in characterizing the dynamic behavior of vehicles and an important factor in design control. Therefore, it is an important part of dynamic simulation models for vehicles, including wheelchairs. This work presents a bench test designed to experimentally monitor and measure the forces transmitted to the ground by a moving wheel. The test bench is composed of a table and a track with a fixed wheel structure and powertrain system. The table is an integrated structure that measures the longitudinal and lateral forces produced by tire contact. This table allows characterization of the tire and tests the tire under varying loads at different slip and camber angles. Additionally, the test bench can also be used to evaluate other tires, such as caster tires. The performances of the new device are illustrated, and the results show the differences between tires, which are related to the dynamic behaviors of wheelchair model. Finally, preliminary experiments performed using the test bench have shown that it is able to monitor and measure the forces generated by the contact between the tire and the ground.

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