Decreased capacity for type-specific-antigen synthesis accounts for high prevalence of nontypeable strains of group B streptococci in Mexico

The low incidence of group B streptococcal (GBS) invasive neonatal disease in Mexico has been attributed to the low prevalence of serotype III strains, a major serotype in developed countries. In addition, nontypeable strains account for 12% of the isolates in Mexico and < 1% of the isolates in the United States. In this study, 57 GBS isolates (28 nontypeable by the Lancefield procedure) from carrier and infected neonates and women from Mexico were also examined for the presence of type-specific antigen by an enzymatic procedure using N-acetylmuramidase digestion of the cell wall to release soluble type-specific antigen. Of the 28 nontypeable strains from Mexico, 23 were typeable by the enzyme extraction procedure, with serotype III being the predominant serotype in invasive disease. These results suggest that nontypeable isolates of GBS should be further examined by the enzymatic extraction procedure to determine the presence of type-specific antigen. Furthermore, these limited results suggest that serotype III is likely a major serotype in invasive disease also in Mexico.     

Accelerating entry into transitional employment in a psychosocial rehabilitation agency.

Hypothesized that the process of vocational rehabilitation could be accelerated by artificially limiting the length of time members were assigned to prevocational crews. 107 clients admitted to a psychosocial rehabilitation program classified according to prior work experience, were assigned to either the standard gradual vocational program or an accelerated program requiring their early involvement in transitional employment. After 15 mo, 20% of the accelerated Ss were in competitive employment, compared with 7% of gradual Ss. 15% of accelerated Ss were in prevocational crews, compared with 35% of gradual Ss. All 7 of the members working full-time at 15 mo were in the accelerated group. Work-experienced Ss benefited from the accelerated approach. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Chemical reaction and ignition in mixtures of magnesium and sodium nitrate

The isothermal kinetics and self-heating in binary mixtures of magnesium and sodium nitrate have been studied as a function of temperature and reactant composition. The effects of reduced pressures (down to 10⁻¹ torr) and of replacing the air over the reactants by argon have been examined. Comparative studies of mixtures of sodium nitrate with magnesium oxide, aluminium oxide, and aluminium were also made. From these measurements it is concluded that magnesium is oxidized in the melt by oxygen atoms produced by the decomposition of sodium nitrate and that it is the exothermicity of this reaction which leads to ignition.     

Nickel Plating for Improved Electrical Contact to Aluminum

A plating for electrical contact surfaces should be selected on the bases of acceptable electrical characteristics (in conjunction with common contact surfaces) and of adequate corrosion resistance in the anticipated environments. One of the problem electrical interfaces which must be considered is between the selected plating and nonplated aluminum contact surfaces.     

Hypertonic-hyperoncotic solutions in open-heart surgery

PURPOSE: To examine relationships between tobacco use and use of other substances among U.S. high school students, by gender and racial/ethnic subgroups. METHODS: Data about tobacco and other substance use were analyzed from the 1995 national Youth Risk Behavior Survey implemented by the Centers for Disease Control and Prevention. RESULTS: Compared to nonsmokers, current smokers were significantly more likely to report use of all other substances we examined, including lifetime use of cocaine, inhalants, other illegal substances, and multiple substances and current alcohol use, episodic heavy drinking, marijuana use, and cocaine use. A strong dose-dependent relationship between current cigarette smoking and other substance use was identified. Among smokeless tobacco users, a strong dose-dependent relationship was found for all examined substances with the exception of lifetime and current cocaine use. Finally, a pattern of risk emerged suggesting that the likelihood of other substance use increases as students move from no tobacco use to smokeless tobacco use only, to cigarette smoking only, and to use of both smokeless tobacco and cigarettes. CONCLUSIONS: Programs designed to prevent tobacco or other substance use should consider that such use often occurs concomitantly.