Air Pollution Related Asthma Inpatient Hospital Admission in the Las Vegas Valley

Asthma is a chronic respiratory condition characterized by inflammation in the lungs that causes airflow to be restricted. In Southern Nevada’s Las Vegas Valley, the natural basin geography causes air pollutants to accumulate. Research has linked air pollution with worsening asthma symptoms. The goal of this study was to determine the non-linear lagged relationship between Asthma Related Inpatient Hospital Admissions (ARIHA) and the Environmental Protection Agency’s (EPA) criteria air pollutants in the Las Vegas Valley using hospital and pollution monitoring station data. Overall, a statistically significant increased RR of ARIHA between 7 and 13 days after exposure to PM2.5 24-hour average levels from 0-35 μg/m3, and from 9-10 days after exposure to PM2.5 24-hour average 75 μg/m3 was found. Finally, 17 ZIP codes exhibited a statistically significant increased RR of ARIHA after adjusting for all variables, revealing a heterogeneous distribution of ZIP codes at a higher risk of ARIHA

Studies of highway skew slab-bridges with curbs. A report of an investigation conducted by the Engineering Experiment Station, University of Illinois,

On t.p. of v. 2: A report of an investigation conducted by the Engineering Experiment Station, University of Illinois, in cooperation with the Bureau of Public Roads, U. S. Dept. of Commerce and the Division of Highways, State of Illinois.Bibliographical footnotes.pt. 1. Results of analyses, by V. P. Jensen and J. W. Allen.--pt. 2. Laboratory research, by M. L. Gossard [and others

The Thermolysis of Bornyl and Iso-Bornyl Acetates

Recent investigations in the area of acetate gas phase thermolysis indicate a mechanism which involves a similar transition state despite the acetate used. The reaction preferentially goes through a cis-elimination with the β-hydrogen atoms, proceeding through a six-membered ring transition state. The purpose of this study is to examine the effect of a strained bicyclic ring system upon the mechanism of acetate thermolysis. Throuqh kinetic studies and product identification of the pyrolyzed products of bornyl and iso-bornyl acetate, an insight into the preferred mechanism can be obtained. A previous study (cited later) indicated that the accepted six-membered cis-elimination is not the mechanism which strained bicyclic acetates preferred. This paper will, therefore, examine this question and determine if inconsistent products and kinetics are indeed obtained

Genetic and biochemical characterization of Brucella abortus strain RB51

Brucella abortus strain RB51, a naturally derived rough variant, has been proposed to replace strain 19 for use as a vaccine against brucellosis in cattle. Utilizing fingerprinting and standard biotyping techniques, it was possible to differentiate RB51 from other brucellae and to ascertain the stability of RB51. Standardization of a genomic fingerprinting procedure using restriction endonuclease profiles of total DNA from Brucella are described. Although the focus was principally on B. abortus isolates from cattle, the investigation included field isolates from bison and elk, reference strains, vaccinal strains, and genetically-engineered brucellae;Pulsed-field gel electrophoresis profiles of the reference type strains allowed separation of the strains to the level of species. A unique fingerprint relative to other brucellae was discovered for RB51, using profiles of genomic DNA digested with the restriction endonuclease Xba I;Stability of RB51 after animal passage and high passage on artificial media was determined using standard methods for characterizing brucellae. Techniques included biochemical, morphological, antigenic, phage susceptibility, and antibiotic resistance. RB51 retained rough colonial morphology with no detectable O-antigen of Brucella lipopolysaccharide and remained resistant to rifampin or to penicillin and sensitive to tetracycline following repeated passage. No detectable changes in characteristic oxidative metabolic profiles on selected amino-acid or carbohydrate substrates were demonstrated following in vivo or repeated in vitro passage;Genomic fingerprints of reference strains and biovars of Brucella were analyzed to obtain information on the genetic relatedness among the strains. Included were four newly described isolates of Brucella from the common seal, harbor porpoise, and common dolphins. Distance matrix analyses were done and a dendrogram was constructed. Results support the designation of an additional genomic group(s) of Brucella;Comparison of cell wall structure of RB51 and B. abortus strain 2308 using transmission electron microscopy revealed variation in surface properties indicating modifications in acidic polysaccharide associated with lipopolysaccharide. The ultrastructural characteristics of the cell wall contributes to the understanding of B. abortus by demonstrating surface components that may be involved in cellular interactions

Cognitive Information Processing

Contains reports on one research project.National Institutes of Health (Grant 5 P01 GI114940-05)Joint Services Electronics Programs (U.S. Army, U. S. Navy, and U. S. Air Force) under Contract DAAB07-71-C-030

Non-iterative and exact method for constraining particles in a linear geometry

We present a practical numerical method for evaluating the Lagrange multipliers necessary for maintaining a constrained linear geometry of particles in dynamical simulations. The method involves no iterations, and is limited in accuracy only by the numerical methods for solving small systems of linear equations. As a result of the non-iterative and exact (within numerical accuracy) nature of the procedure there is no drift in the constrained geometry, and the method is therefore readily applied to molecular dynamics simulations of, e.g., rigid linear molecules or materials of non-spherical grains. We illustrate the approach through implementation in the commonly used second-order velocity explicit Verlet method.Comment: 12 pages, 2 figure

Intrinsic and selected resistance to antibiotics binding the ribosome: analyses of Brucella 23S rrn, L4, L22, EF-Tu1, EF-Tu2, efflux and phylogenetic implications

BACKGROUND: Brucella spp. are highly similar, having identical 16S RNA. However, they have important phenotypic differences such as differential susceptibility to antibiotics binding the ribosome. Neither the differential susceptibility nor its basis has been rigorously studied. Differences found among other conserved ribosomal loci could further define the relationships among the classical Brucella spp. RESULTS: Minimum inhibitory concentration (MIC) values of Brucella reference strains and three marine isolates to antibiotics binding the ribosome ranged from 0.032 to >256 μg/ml for the macrolides erythromycin, clarithromycin, and azithromycin and 2 to >256 μg/ml for the lincosamide, clindamycin. Though sequence polymorphisms were identified among ribosome associated loci 23S rrn, rplV, tuf-1 and tuf-2 but not rplD, they did not correlate with antibiotic resistance phenotypes. When spontaneous erythromycin resistant (ery(R)) mutants were examined, mutation of the peptidyl transferase center (A2058G Ec) correlated with increased resistance to both erythromycin and clindamycin. Brucella efflux was examined as an alternative antibiotic resistance mechanism by use of the inhibitor L-phenylalanine-L-arginine β-naphthylamide (PAβN). Erythromycin MIC values of reference and all ery(R )strains, except the B. suis ery(R )mutants, were lowered variably by PAβN. A phylogenetic tree based on concatenated ribosomal associated loci supported separate evolutionary paths for B. abortus, B. melitensis, and B. suis/B. canis, clustering marine Brucella and B. neotomae with B. melitensis. Though Brucella ovis was clustered with B. abortus, the bootstrap value was low. CONCLUSION: Polymorphisms among ribosomal loci from the reference Brucella do not correlate with their highly differential susceptibility to erythromycin. Efflux plays an important role in Brucella sensitivity to erythromycin. Polymorphisms identified among ribosome associated loci construct a robust phylogenetic tree supporting classical Brucella spp. designations