Mass transfer inside oblate spheroidal solids: modelling and simulation

A numerical solution of the unsteady diffusion equation describing mass transfer inside oblate spheroids, considering a constant diffusion coefficient and the convective boundary condition, is presented. The diffusion equation written in the oblate spheroidal coordinate system was used for a two-dimensional case. The finite-volume method was employed to discretize the basic equation. The linear equation set was solved iteratively using the Gauss-Seidel method. As applications, the effects of the Fourier number, the Biot number and the aspect ratio of the body on the drying rate and moisture content during the process are presented. To validate the methodology, results obtained in this work are compared with analytical results of the moisture content encountered in the literature and good agreement was obtained. The results show that the model is consistent and it may be used to solve cases such as those that include disks and spheres and/or those with variable properties with small modifications

Adolpho Lutz and controversies over the transmission of leprosy by mosquitoes Adolpho Lutz e as controvérsias sobre a transmissão da lepra por mosquitos

During his years of study in Switzerland and Germany, Adolpho Lutz published his first articles on zoology, clinical practice, and therapeutics. In Limeira, São Paulo, he began studies on animal and human diseases caused by germs and parasites. In 1885-86, Lutz traveled to Hamburg to study the morphology of germs related to skin diseases, in conjunction with Paul Gerson Unna, one of Germany's foremost dermatologists. He proposed the inclusion of Hansen's and Koch's bacilli in a new genus. In 1889, Unna nominated his student as physician-in-chief of the Leper Settlement on Molokai Island, Hawaii. From then on, Lutz sustained the theory that the disease was transmitted by mosquitoes. He conducted research to prove this theory when he was head of the Instituto Bacteriológico de São Paulo (1893-1908) and, later, after he moved to the Instituto Oswaldo Cruz (1908-1940). Although this research was not successful, on commissions and at congresses in which he participated until his death in October 1940, he still held to his conviction that leprosy was transmitted by mosquitoes.<br>Quando estudava na Suíça e Alemanha, Adolpho Lutz publicou os primeiros trabalhos sobre zoologia, clínica e terapêutica. Em Limeira, São Paulo, iniciou estudos sobre doenças humanas e animais causadas por germes e parasitas. Em 1885-86, viajou para Hamburgo para estudar microrganismos relacionados a doenças de pele sob a orientação de Paul Gerson Unna, um dos mais renomados dermatologistas alemães. Propôs a inclusão dos bacilos de Hansen e Koch num novo gênero. Em 1889, Unna indicou seu discípulo como chefe dos serviços médicos do Leprosário de Molokai, no Havaí. Lutz passou a defender a transmissão da doença por mosquitos. Realizou pesquisas para provar esta teoria depois que assumiu a chefia do Instituto Bacteriológico de São Paulo (1893-1908) e, sobretudo, após a transferência para o Instituto Oswaldo Cruz (1908-1940). Apesar de não terem sido bem-sucedidas estas pesquisas, sustentou a transmissão da lepra por mosquitos nas comissões e congressos de que participou, até sua morte em outubro de 1940