Showing papers by "Universidade Federal de Minas Gerais published in 1985"

An experimental vaccine against American dermal leishmaniasis: experience in the State of Espírito Santo, Brazil.

Abstract: A vaccine prepared from killed and sonicated promastigotes of five Brazilian strains of Leishmania was used during an epidemic of American dermal leishmaniasis that occurred in Viana county, State ...

Thermodynamical properties of the transverse Ising model

Abstract: A new effective field theory is proposed and used to derive the thermodynamical properties of the transverse Ising model. The formalism is based on an exact formal spin identity for the two-state transverse Ising model and utilizes an exponential operator technique. The method, which can explicitly and systematically include correlation effects, is illustrated in several lattice structures by employing its simplest approximation version (in which spin-spin correlations are neglected). The lines of critical points in the Ω- T plane as well as the thermal behaviour of both transverse and longitudinal magnetizations are analysed for square and simple cubic lattices. It is shown that the present formalism, in spite of its simplicity, yields results which represent a remarkable improvement on the standard mean field treatment (MFA).

[Angiostrongylus vasorum (Baillet, 1866) Nematoda: Protostrongylidae, in dogs of Minas Gerais, Brazil].

Abstract: For the first time Angiostrongylus vasorum in Canis familiaris in Minas Gerais State, Brazil, is described. The description and measurements of three males and ten females are presented together with a diagram of the parasite.

Foco de leishmaniose tegumentar americana nos municípios de Viana e Cariacica, Estado do Espirito Santo, Brasil

Abstract: Descreve-se um foco de leishmaniose tegumentar americana abrangendo quatro localidades dos municipios de Viana e Cariacica situados proximo ao litoral do Estado do Espirito Santo, Brasil. Foram diagnosticados 71 casos no periodo de maio de 1978 a dezembro de 1982. A confirmacao laboratorial foi obtida pela intradermorreacao de Montenegro em 66 pacientes e pelo encontro do parasita em 15. A faixa etaria mais acometida foi a de 0-10 anos. Amostras do parasita isoladas de 3 pacientes e de 27 caes foram classificadas como Leishmania braziliensis braziliensis. De apenas dois Proechimys iheringi, entre 257 mamiferos silvestres estudados, isolou-se Leishmania, que foi identificada como Leishmania mexicana aristedesi. As especies de flebotomineos mais numerosas (Lutzomyia intermedia, L. fischeri e L. migonei) apresentaram um elevado grau de adaptacao aos ambientes intra e peri-domibiliar. Levantou-se a hipotese da transmissao estar ocorrendo no intra e peri-domicilio.

A clinico-epidemiological survey of schistosomiasis mansoni in a hyperendemic area in Minas Gerais State (Comercinho, Brazil). I. Differences in the manifestations of schistosomiasis in the town centre and in the environs.

Abstract: A cross-sectional survey of schistosomiasis was done in Comercinho (Minas Gerais State, Brazil) Faecal (Kato-Katz technique) and physical examinations were performed on 90% and 79% of the population (1474 inhabitants), respectively The rate of infection with Schistosoma mansoni was 70%, the geometric mean of eggs was 334/g of faeces and 7% of the infected individuals had splenomegaly The rate of infection, faecal egg counts and the rate of splenomegaly were significantly higher in the environs (zones 3 and 4) of the town than in the central areas (zones 1 and 2) of Comercinho This difference seemed to be determined by the social differences existing between the population in the central area and the environs; in the environs the heads of families were predominantly manual workers (73 and 94% respectively), only 10 and 3% of the houses had piped water supply and less than 14% were of better quality

X-ray diffraction studies of structural changes in the system Zr50Co50−xNix (0 ⩽ x ⩽ 50): III

Abstract: Structural studies were carried out on the pseudobinary system Zr 50 Co 50− x Ni x (0 ⩽ x ⩽ 50) using primarily X-ray diffraction, together with dilatometry and hardness measurements. The room temperature X-ray measurements clearly reveal two distinct structures across the system. In the region 0 ⩽ x ⩽ 14 the alloys adopt a b.c.c. CsCl-type structure, whereas compositions with 14 ⩽ x ⩽ 50 have an orthorhombic CrB-type structure. Significant changes in the b and c parameters of the orthorhombic structure were observed in the composition range (16 ⩽ x ⩽ 50); these changes indicated a continuous range of solid solutions within the orthorhombic phase field. The atomic volumes, however, exhibited very little change with composition owing to the compensating effect of the b and c variations. The dilatometric and hardness measurements clearly indicate the presence of a reversible martensitic phase change in these alloys and are consistent with the X-ray diffraction studies.

Método imunocitoquímico para a identificaçäo de amastigotas do Trypanosoma cruzi em cortes histológicos de rotina

Abstract: A tecnica da peroxidase antiperoxidase foi aplicada para a identificacao de amastigotas do T. cruzi em cortes histologicos de rotina. Os tecidos foram obtidos de pacientes chagasicos cronicos e de animais na fase aguda da infeccao chagasica. Anti-soros especificos produzidos em coelho contra as cepas CL, Y e Emane do T. cruzi foram utilizados como reagentes primarios na tecnica imunocitoquimica. Soro de coelho normal foi utilizado como controle negativo e culturas de macrofagos peritoniais de camundongos infectados com tripomastigotas e apresentando abundantes amastigotas intracelulares foram utilizadas como controles positivos. Coloracao positiva ocorreu especificamente nos amastigotas intra e extra-celulares em todos os tecidos testados com os anti-soros contra as tres diferentes cepas do T. cruzi. Os amastigotas isolados ou formando ninhos intracelulares tornaram-se facilmente identificaveis nas preparacoes histologicas utilizando-se o pequeno ou medio aumento do microscopio. O presente metodo aumenta a probabilidade do diagnostico do parasitismo na doenca de Chagas, e evita confundir-se amastigotas com outros microrganismos morfologicamente semelhantes.

Turbulent Fluid Flow Phenomena in a Water Model of an AOD System

Abstract: Experimental measurements are reported regarding fluid flow and turbulence property measurements in a water model of an AOD vessel. Laser velocimetry was used to determine the time smoothed velocities, the turbulent kinetic energy, and the Reynolds stresses in the system; in addition, the rate of melting of immersed ice rods was also measured to determine the local heat transfer rates. The measurements have shown that for the model AOD studied both the velocity fields and the distribution of the turbulent kinetic energy were quite uniform; the absence of inactive or dead zones would render these systems ideal for mixing and for a range of ladle metallurgical operations. The rate at which immersed ice rods dissolved depended on both the local velocities and on the turbulence levels; a previously developed correlation could be employed to predict the appropriate heat transfer coefficients. Finally, the rate of turbulent energy dissipation per unit volume in real industrial AOD vessels was found to be much higher than in any other ladle metallurgy operations. This could raise interesting possibilities regarding the more widespread use of these systems for molten metals processing.

Ectoparasitos de roedores da regiäo urbana de Belo Horizonte, MG: III. Indices pulicidianos, anoplurianos e acarianos em Rattus Norvegicus norvegicus

Abstract: Indices pulicidianos, anoplurianos e acarianos, globais e especificos foram determinados para os ectoparasitos de Rattus norvegicus norvegicus capturados em zona urbana de Belo Horizonte, Minas Gerais, Brasil, no periodo de junho de 1980 a setembro de 1982. Tendo-se em vista os valores limites ou criticos atribuidos aos indices pulicidianos, sobretudo ao indice "cheopis" e propostos por diversos autores como medida complementar de vigilância epidemiologica para peste bubonica, a comunidade de Belo Horizonte poderia ter estado exposta a esta infeccao, uma vez que os indices globais anuais de 0,3 a 2,4 e a pulga prevalente foi Xenopsylla cheopis (99,2%), com os maiores indices coincidindo com o final da estacao seca-fria. Em duas ocasioes, a comunidade poderia ter permanecido altamente exposta a infeccao, ja que os indices-limites tolerados foram suplantados: 8,8 (outubro 1980) e 6,2 (setembro 1982). Sugere-se que medidas profilaticas como anti-ratizacao e desinsetizacao sejam eficazmente aplicadas ao final da estacao seca-fria, ou anteriormente a chegada das chuvas, sendo sucedidas pela desratizacao. Informacoes sobre indices anoplurianos e acarianos sao importantes para que se possa, no exclusivas de roedores

Mode Specific Resonance Decay

Abstract: Mode specific resonance decay is demonstrated directly by Fast Fourier Transform (FFT) time propagation of resonance wave packets for an ABA molecule modeled by coupled Morse oscillators. Fast and slow decay correlates with local and hyperspherical modes which have their wave function lobes directed towards dissociation exits and ridges of the potential, respectively, in excellent analogy to Hose and Taylor's analysis of the Henon-Heiles system. The decay shows no correlation with energy or symmetry. The FFT method yields details of the decay mechanism. The results are related to observations of mode specific unimolecular processes in bulk.

Phase diagrams for the bond- and site-diluted transverse ising model

Abstract: A unified effective-field treatment for both quenched bond- and site-diluted transverse Ising models is presented. The method which can explicitly and systematically include correlation effects, is applied to several Z-fold-coordinated lattices (Z = 3, 4 and 6) in its simplest approximate version. Although mathematically simple, it yields results quite superior to those currently obtained within the standard molecular-field treatments. Whenever comparison is possible a satisfactory qualitative (and to a certain extent quantitative) agreement is observed with results available in the literature. A particular emphasis is given to the honeycomb lattice for which no unified treatment has been done.

[Ectoparasites of rodents of the urban region of Belo Horizonte, MG. II. Variations of the infestation indices in Rattus norvegicus norvegicus].

Abstract: The indices of infestation by the mites Echinolaelaps echidninus and Laelaps nuttalli, the louse Popyplax spinulosa and the flea Xenopsylla cheopis, obtained monthly, from June 1980 to September 1982, on Rattus norvegicus norvegicus in the city of Belo Horizonte, Minas Gerais state, Brazil were related to seasonal period, sex of the host and area of capture. Mites and insects showed different behaviour in relation to these factors. Only the fleas and lice exhibit significant association between the rodents' infestation and the seasonal period, or between the infestation and the rodents' sex or else a variation of the distribution by the three main areas of capture. The fleas showed the highest indices of infestation in the warm-rainy season (October to March) while the infestation by the lice was more prevalent in the dry-cool season. The climatic factors most related with the hosts' infestation were, in decreasing order, rainfall, temperature and relative humidity. Fleas and lice preferentially infested male rodents, being infestation by X. cheopis highly significant.

Mineralogy of the bocaiuva iron meteorite: a preliminary study

Abstract: The Bocaiuva iron contains 10 to 15% by volume of silicate inclusions which are surrounded by kamacite (6.5 wt % Ni). The metal shows a Widmanstatten pattern in metal areas devoid of silicates; taenite evolved in plessite fields. The silicate inclusions occur as nodules, and as irregular or chain-like aggregates in which olivine may be rounded or faceted. The magnesian silicates (forsterite, enstatite, diopside) are similar in composition to those of the group IAB irons, whereas the interstitial plagioclase is much more calcic (An 50) than that usually found. Iron sulfide occurs as pyrrhotite and contains 1–2 wt% Cu. Chromite and euhedral magnetite are accessory phases always associated with pyrrhotite. Some patches of pyrrhotite enclose rounded chromite and small plagioclase crystals displaying compositions different from those of the ground mass of the inclusions. Schreibersite shows a compositional variability. This preliminary study underlines the unusual nature of Ms iron and raises several questions concerning the genetic relations between silicates, sulfide and metal, and the thermal history of the whole material.

O ensino da “Catalogação de assunto”

Abstract: Apresenta e analisa o ensino tradicional de catalogacao de assunto. Cita varios autores que escreveram sobre o assunto, tentando retratar o estado da arte. Sugere uma disciplina de coroamento que habilitaria melhor os alunos para atuarem em diversos tipos de bibliotecas.

O surgimento do sistema possessivo do português coloquial: uma interpretação funcional

Abstract: This paper the organization of possessive phrases in modern Brazilian Portuguese, and attempts to set up a functional hypothesis to explain its emergence in the language. The possessive system of Brazilian Portuguese is assymetrical, and includes, on one hand, possessive pronouns like meu (s) 'my' for the first person singular and plural, and for the second singular; and on the other hand, analytic forms like de voces 'your (pl)' for the second person plural, third singular and third plural. The diachronic emergence of such a system is explained as result of the working of two principles, which are "functional" in the sense that they represent a tendency toward a grammar which is more adapetd to the needs of communication, rather than a grammar whixh is merely simpler. These principles are: One: Ambiguity must be avoided wheneer it precules recovering of the grammatical person referred to. Two: When a system is altered to suit Principle One, onle minimum alterations are allowed.