Abstract The deposition of DLC films on 321H stainless steel aims at attributing properties such as high wear resistance and low friction coefficient to the substrate material. Nitrogen added to DLC can improve the film adhesion to metal substrates, but the investigation of its effect on corrosion resistance, an important property for stainless steels, is lacking. The DLC film was deposited by plasma-enhanced chemical vapor deposition (PECVD) using a pulsed-DC power supply with a gas mixture of Ar and CH4, and to the DLC(N) film deposition was used CH4 and N2 varying the percentage of nitrogen from 10 to 50% in the treatment. DLC films improved both the wear and corrosion resistance of 321H stainless steel. The results show that the 10, 20 and 30% of N2 supply during the deposition increased the adhesion of the film on the substrate, enhancing the wear resistance of the treated material. The addition of 40 and 50% of N2 during the deposition, however, impaired the corrosion resistance compared with the substrate. An improvement of adhesion, wear and corrosion resistance were observed for 30% N2 condition. Thus, the incorporation of suitable concentration of nitrogen modifies the features of the DLC film, obtaining a good combination of high wear resistance and corrosion protection due to a combination of structure, high thickness, and high adhesion of the film to 321H stainless steel.

We prove a de Rham-like theorem for foliated bundles F ! (M; F )¼ ! B showing that the cohomology H¤( F ) is isomorphicto the equivariant cohomology H¡ ³ eB; C1 (F); ¡ = ¼1 (B)and eB the universal covering of B. When B is an Eilenberg-Mac Lane space K (¡; 1) the cohomology H¤ ( F ) is the cohomology of the ¡-module C1 (F). This gives algebraic models for H¤ ( F ) and geometrial models for the cohomology of the ¡-module C1 (F). Using this isomorphism and a theorem of J. Palis and J.C. Yoccoz on the triviality of centralizers of diffeomorphisms, [14] and [15] we show that H¤( F ) is infinite dimensional for a large class of foliated bundles. Using this isomorphism R. u. Luz computed in [9] the cohomology of the foliated bunddles suspensions of actions of Z P by afine transformations of T Q. AMS (MOS) Subj class: 57R30

Um retrovírus foi isolado de um paciente brasileiro com "Síndrome de Imunodeficiência Adquirida" (SIDA/AIDS) e caracterizado em termos de sua reatividade com soros de indivíduos infectados com vírus da imunodeficiência humana dos tipos 1 e 2 (HIV-1 e HIV-2). A análise antigênica por "Western blot" revelou que o isolado brasileiro é bastante similar a uma cepa de HIV-1 bem caracterizada. A identificação do retrovírus como HIV-1 e não HIV-2 é reforçada pelo fato dos anticorpos do paciente do qual foi isolado o vírus não terem reagido com a glicoproteínas de envelope de 140 kDa, específica para HIV-2.

A retrovirus infecting a Brazilian AIDS patient was isolated and characterized in terms of its reactivity with sera from individuals infected with human immunodeficiency viruses 1 and 2 (HIV-1 and HIV-2). The Western blot analysis revealed that the Brazilian isolate is very similar to the well characterized HIV-1 strain. The serum of the patient from whom the virus was isolated did not react with the 140 kDa envelope glycoprotein specific for HIV-2.

Foram estudados soros de pessoas de diferentes grupos etários coletados em 1976, 1978 e 1979 para verificar a presença de anticorpos inibidores da hemaglutinação contra diversas estirpes de vírus da influenza A dos subtipos H3N2 e H1N1. A ocorrência da infecção pelo subtipo H3N2 foram detectados em 1976 e 1978 mas em 1979, a circulação desse subtipo de vírus foi limitada. A prevalência de anticorpo contra A/São Paulo/1/78 (H1N1) foi significativamente maior do que para A/USSR/90/77 (H1N1) em 1978. No entanto em 1979, a estirpe predominante foi A/USSR/90/77 (H1N1). As pessoas com idade inferior a 20 anos foram as mais afetadas pelo subtipo H1N1, enquanto que indivíduos com mais de 20 anos já apresentavam anticorpos para esse subtipo em 1976, antes do ressurgimento dessa estirpe. A infecção pelo vírus H3N2 em 1978 ocorreu em 65,4% de crianças do grupo etário de 0-4 anos; 47,0% de crianças do mesmo grupo tinham anticorpos para o vírus H1N1 em 1979. Anticorpos para o vírus da influenza suina foram detectadas em 60% de pessoas com mais de 60 anos de idade.

Sera of persons of different age groups collected in 1976, 1978 and 1979 were tested for the presence of HI antibodies against various strains of the H3N2 and H1N1 subtypes of influenza virus. The occurrence of infection by H3N2 subtype was recorded during the 1976-1978 period but in 1979, circulation of this subtype of virus was limited. The prevalence of antibody against A/São Paulo/1/78 (H1N1) was significantly higher than that of antibody to A/USSB/90/77 (HIND in 1978. However in 1979 the predominant strain was A/USSR/90/77 (HIND. Persons under 20 years of age were the most affected by H1N1 subtype. Antibodies to H1N1 subtype were detected in sera of individuals older than 20 years in 1976, before the re-emergence of this strain. Serological results indicate that infections by H3N2 subtype in 1978 occurred in 65.4% of young children (0-4 year group). About 47.0% of children from the 0-4 year group had antibodies to H1N1 subtype in 1979. Antibodies to swine influenza virus were detected in 60% of 60+ year old people.