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We report the detection of Deuterium absorption at redshift 2.525659 towards Q1243+3047. We describe improved methods to estimate the Deuterium to Hydrogen abundance ratio (D/H) in absorption systems, including improved modelling of the continuum level, the Lyα forest and the velocity structure of the absorption. Together with improved relative flux(More)
We investigate the ionization state of the damped Ly system at z ¼ 2:62 toward GB 1759+7539 through an analysis of ionic ratios sensitive to photoionization: Ar 0 /mately half of the metals arise in a mostly neutral velocity component with H i/H > 0:9, based on Fe þþ =Fe þ < 0:013. In contrast, the remaining half exhibit Fe þþ =Fe þ % 0:3, indicative of a(More)
Two oligonucleotide primer sets for the discrimination of Streptococcus pneumoniae from "pneumococcus-like" oral streptococcal isolates by PCR were developed. Genomic subtractive hybridization was performed to search for differences between Streptococcus pneumoniae strain WU2 and the most closely related oral streptococcus, Streptococcus mitis strain 903.(More)
The red complex, which includes Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia (formerly Bacteroides forsythus), are recognized as the most important pathogens in adult periodontal disease. These bacteria are usually found together in periodontal pockets, suggesting that they may cause destruction of the periodontal tissue in a(More)
This study aimed to determine the frequency of smoking and to explore factors associated with the smoking habits of female students at a dental hygiene school in Japan. Questionnaires regarding cigarette smoking were given to 168 female students. The response rate was 97.6%. The prevalence of smoking, including current and occasional smokers, was 20.3%.(More)
We report the measurement of the primordial D/H abundance ratio towards QSO HS 0105+1619. The column density of the neutral hydrogen in the z ≃ 2.536 Lyman limit system is high, log N HI = 19.422 ± 0.009 cm −2 , allowing for the deuterium to be seen in 5 Lyman series transitions. The measured value of the D/H ratio towards QSO HS 0105+1619 is found to be(More)
Both hydrogen sulfide (H2S) and methyl mercaptan (CH(3)SH) are frequently detected in large amounts in malodorous mouth air. We investigated the bacterial composition of saliva of 30 subjects with severe oral malodor exhibiting extreme CH(3)SH/H(2)S ratios (high H(2)S but low CH(3)SH concentrations, n 5 14; high CH(3)SH but low H2S concentrations, n 5 16)(More)
This study investigated the inhibitory effect of probiotic Enterococcus faecium WB2000 on biofilm formation by cariogenic streptococci. The ability of E. faecium WB2000 and JCM5804 and Enterococcus faecalis JCM5803 to inhibit biofilm formation by seven laboratory oral streptococcal strains and 13 clinical mutans streptococcal strains was assayed. The(More)
Big Bang Nucleosynthesis (BBN) is the synthesis of the light nuclei, Deuterium, 3 He, 4 He and 7 Li during the first few minutes of the universe. This review concentrates on recent improvements in the measurement of the primordial (after BBN, and prior to modification) abundances of these nuclei. We mention improvement in the standard theory, and the(More)
Periapical lesions are caused by bacterial infections. The fundamental objective of endodontic treatment is to eliminate bacteria present in the root canal system because they play an important role in the development and maintenance of periapical lesions. Therefore, confirming the absence of bacteria before filling root canals is important. Anaerobic(More)