Electromagnetic compatibility

This edition represents a thoroughly revised, updated and more comprehensive version of the previous book entitled 'Elektromagnetische compatibiliteit' by Jasper Goedbloed (Kluwer Techniek, 1990) and in 1992/1997 a revised and translated English edition of this book was published

Electromagnetic compatibility

This edition represents a thoroughly revised, updated and more comprehensive version of the previous book entitled 'Elektromagnetische compatibiliteit' by Jasper Goedbloed (Kluwer Techniek, 1990) and in 1992/1997 a revised and translated English edition of this book was published

Modulation of parasitemia and antibody responce to Trypanosoma cruzy by cyclophosphamide in Calomys callosus (Rodentia, Cricetidae) Modulação da parasitemia e da resposta de anticorpos ao Trypanosoma cruzi pela ciclofosfamida em Calomys callosus (Rodentia, Cricetidae)

Calomys callosus a wild rodent, previously described as harboring Trypanosoma cruzi, has a low susceptibility to infection by this protozoan. Experiments were designed to evaluate the contribution of the immune response to the resistance to T. cruzi infection exhibited by C. calossus. Animals were submitted to injections of high (200 mg/kg body weight) and low (20 mg/kg body weight) doses of cyclophosphamide on days -1 or -1 and +5, and inoculated with 4 x 10³ T. cruzi on day O. Parasitemia, mortality and antibody response as measured by direct agglutination of trypomastigotes were observed. Two hundred mg doses of cyclophosphamide resulted in higher parasitemia and mortality as well as in suppression of the antibody response. A single dose of 20 mg enhanced antibody levels on the 20th day after infection, while an additional dose did not further increase antibody production. Parasitemia levels were not depressed, but rather increased in both these groups as compared to untreated controls. Passive transfer of hyperimmune C. callosus anti-T. cruzi serum to cyclophosphamide immunosuppressed animals resulted in lower parasitemia and mortality rates. These results indicate that the immune response plays an important role in the resistance of C. callossus to T. cruzi.<br>Calomys-callosus, roedor silvestre, que já foi encontrado naturalmente infectado pelo Trypanosoma cruzi, tem baixa suscetibilidade à infecção experimental por este protozoário. Foram feitos experimentos para avaliar a contribuição da resposta imune a essa baixa suscetibilidade. Animais foram submetidos a injeção de doses altas (200 mg/kg peso corporal) ou doses baixas (20 mg/kg peso corporal) de ciclofosfamida nos dias -1 ou -1 e +5, e inoculados com 4 x 10³ T. cruzi no dia O. Observou-se a curva de parasitemia, mortalidade e resposta de anticorpos medida por aglutinação direta de tripomastigotas. Doses de 200 mg resultaram em parasitemia e mortalidade mais elevada e supressão da resposta de anticorpos. Uma dose de 20 mg aumentou os níveis de anticorpos no 20º dia após a infecção, enquanto a administração de uma segunda dose não alterou significativamente a produção de anticorpos. Os níveis de parasitemia não diminuíram, mas pelo contrário, elevaram-se em relação aos animais testemunhos, em ambos os grupos. A transferência passiva de soro anti-T. cruzi de C. callosus resultou em parasitemia e mortalidade mais baixa nos animais imunossuprimidos. Estes resultados indicam que a resposta imune é um importante fator na resistência de C. callosus à infecção por T. cruzi

Arc plasma torch modeling

International audienceArc plasma torches are the primary components of various industrial thermal plasma processes involving plasma spraying, metal cutting and welding, thermal plasma CVD, metal melting and remelting, waste treatment, and gas production. They are relatively simple devices whose operation implies intricate thermal, chemical, electrical, and fluid dynamics phenomena. Modeling may be used as a means to better understand the physical processes involved in their operation. This article presents an overview of the main aspects involved in the modeling of DC arc plasma torches: the mathematical models including thermodynamic and chemical nonequilibrium models, turbulent and radiative transport, thermodynamic and transport property calculation, boundary conditions, and arc reattachment models. It focuses on the conventional plasma torches used for plasma spraying that include a hot cathode and a nozzle anode