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- Schael, S, et al.
(author)
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Precision electroweak measurements on the Z resonance
- 2006
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In: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
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Research review (peer-reviewed)abstract
- We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLID experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, m(Z) and Gamma(Z), and its couplings to fermions, for example the p parameter and the effective electroweak mixing angle for leptons, are precisely measured: m(Z) = 91.1875 +/- 0.0021 GeV, Gamma(Z) = 2.4952 +/- 0.0023 GeV, rho(l) = 1.0050 +/- 0.0010, sin(2)theta(eff)(lept) = 0.23153 +/- 0.00016. The number of light neutrino species is determined to be 2.9840 +/- 0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward-backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, m(t) = 173(+10)(+13) GeV, and the mass of the W boson, m(W) = 80.363 +/- 0.032 GeV. These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of m(t) and m(W), the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than 285 GeV at 95% confidence level. (c) 2006 Elsevier B.V. All rights reserved.
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- Vásquez, A, et al.
(author)
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Oral administration of lactobacillus and Bifidobacterium strains of intestinal and vaginal origin to healthy human females: re-isolation from faeces and vagina
- 2005
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In: Microbial Ecology in Health and Disease. - 0891-060X. ; 17:1, s. 15-20
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Journal article (peer-reviewed)abstract
- The healthy vaginal ecosystem is maintained by the interaction of the vaginal epithelium and the microflora, where lactobacilli and occasionally bifidobacteria play an important role. Imbalances in the dominance of lactobacilli may lead to bacterial vaginosis or yeast vaginitis. Probiotics may be a means to secure a favourable microbial balance in the vagina and, as the normal vaginal flora ascends from the rectal mucosa, a convenient form of administration may be via the oral gastrointestinal route. Ten healthy women of different ages were orally administered a blend of 12 selected Lactobacillus strains and three Bifidobacterium strains originating from the intestine and the vagina. The daily dose of each Lactobacillus strain was 1-3×109 CFU and 1×108 to 1×109 CFU for each Bifidobacterium strain, and the doses were given in an oatmilk/blueberry drink. The treatment went on for 10 days. Samples of faeces and vaginal fluid were taken immediately before the administration was started, after 10 days of administration and 7 days after the termination of the administration. Five strains were recovered from faeces and three from the vagina after treatment. The test strains could be found in 9 of the 10 volunteers. L. plantarum strains, originally isolated from intestinal mucosa, were recovered from the vagina of five subjects after treatment. The L. plantarum strains, together with one strain of L. crispatus and one L. gasseri strain, were recovered from faeces.
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