| 1. |
- Abazov, V. M., et al.
(author)
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Determination of the strong coupling constant from the inclusive jet cross section in pp collisions at s=1.96 TeV
- 2009
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In: PHYS REV D. - 1550-7998 .- 1550-2368. ; 80, s. 111107-
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Journal article (peer-reviewed)abstract
- We determine the strong coupling constant alpha(s) and its energy dependence from the p(T) dependence of the inclusive jet cross section in pp collisions at s=1.96 TeV. The strong coupling constant is determined over the transverse momentum range 50 < p(T)< 145 GeV. Using perturbative QCD calculations to order O(alpha(3)(s)) combined with O(alpha(4)(s)) contributions from threshold corrections, we obtain alpha(s)(M-Z)=0.1161(-0.0048)(+0.0041). This is the most precise result obtained at a hadron-hadron collider.
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| 2. |
- Abazov, V. M., et al.
(author)
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Measurement of the top quark mass in final states with two leptons
- 2009
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In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 1550-7998 .- 1550-2368. ; 80, s. 092006-
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Journal article (peer-reviewed)abstract
- We present measurements of the top quark mass (m(t)) in tt candidate events with two final state leptons using 1 fb(-1) of data collected by the D0 experiment. Our data sample is selected by requiring two fully identified leptons or by relaxing one lepton requirement to an isolated track if at least one jet is tagged as a b jet. The top quark mass is extracted after reconstructing the event kinematics under the tt hypothesis using two methods. In the first method, we integrate over expected neutrino rapidity distributions, and in the second we calculate a weight for the possible top quark masses based on the observed particle momenta and the known parton distribution functions. We analyze 83 candidate events in the data and obtain m(t)=176.2 +/- 4.8(stat)+/- 2.1(sys) GeV and m(t)=173.2 +/- 4.9(stat)+/- 2.0(sys) GeV for the two methods, respectively. Accounting for correlations between the two methods, we combine the measurements to obtain m(t)=174.7 +/- 4.4(stat)+/- 2.0(sys) GeV.
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| 3. |
- Abazov, V. M., et al.
(author)
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Search for Anomalous Top-Quark Couplings with the D0 Detector
- 2009
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In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 102:9, s. 092002-
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Journal article (peer-reviewed)abstract
- Anomalous Wtb couplings modify the angular correlations of the top-quark decay products and change the single top-quark production cross section. We present limits on anomalous top-quark couplings by combining information from W boson helicity measurements in top-quark decays and anomalous coupling searches in the single top-quark final state. We set limits on right-handed vector couplings as well as left-handed and right-handed tensor couplings based on about 1 fb(-1) of data collected by the D0 experiment.
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| 4. |
- Abazov, V. M., et al.
(author)
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Search for charged Higgs bosons in top quark decays
- 2009
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In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 682:3, s. 278-286
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Journal article (peer-reviewed)abstract
- We present a search for charged Higgs bosons in top quark decays. We analyze the e + jets, mu + jets, ee, e mu, mu mu, tau e and tau mu final states from top quark pair production events, using data from about 1 fb (1) of integrated luminosity recorded by the DO experiment at the Fermilab Tevatron Collider. We consider different scenarios of possible charged Higgs boson decays, one where the charged Higgs boson decays purely hadronically into a charm and a strange quark, another where it decays into a tau lepton and a tau neutrino and a third one where both decays appear. We extract limits on the branching ratio B(t -> H(+)b) for all these models. We use two methods, one where the t (t) over bar production cross section is fixed, and one where the cross section is fitted simultaneously with B(t -> H(+)b). Based on the extracted limits, we exclude regions in the charged Higgs boson mass and tan beta parameter space for different scenarios of the minimal supersymmetric standard model.
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| 5. |
- Ferwerda, Bart, et al.
(author)
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Functional and genetic evidence that the Mal/TIRAP allele variant 180L has been selected by providing protection against septic shock.
- 2009
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In: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 106:25, s. 10272-10277
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Journal article (peer-reviewed)abstract
- Adequate responses by our innate immune system toward invading pathogens were of vital importance for surviving infections, especially before the antibiotic era. Recently, a polymorphism in Mal (Ser180Leu, TIRAP rs8177374), an important adaptor protein downstream of the Toll-like receptor (TLR) 2 and 4 pathways, has been described to provide protection against a broad range of infectious pathogens. We assessed the functional effects of this polymorphism in human experimental endotoxemia, and we demonstrate that individuals bearing the TIRAP 180L allele display an increased, innate immune response to TLR4 and TLR2 ligands, but not to TLR9 stimulation. This phenotype has been related to an increased resistance to infection. However, an overshoot in the release of proinflammatory cytokines by TIRAP 180L homozygous individuals suggests a scenario of balanced evolution. We have also investigated the worldwide distribution of the Ser180Leu polymorphism in 14 populations around the globe to correlate the genetic makeup of TIRAP with the local infectious pressures. Based on the immunological, clinical, and genetic data, we propose that this mutation might have been selected in West Eurasia during the early settlement of this region after the out-of-Africa migration of modern Homo sapiens. This combination of functional and genetic data provides unique insights to our understanding of the pathogenesis of sepsis.
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| 6. |
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| 7. |
- Suzuki, R, et al.
(author)
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Alcohol and postmenopausal breast cancer risk defined by estrogen and progesterone receptor status : A prospective cohort study
- 2005
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In: Journal of the National Cancer Institute. - Karolinska Inst, Div Nutr Epidemiol, Natl Inst Environm Med, Dept Med Epidemiol & Biostat, S-17177 Stockholm, Sweden. Tokyo Metropolitan Komagome Hosp, Dept Surg & Breast Oncol, Tokyo Metropolitan Canc & Infect Dis Ctr, Tokyo, Japan. Harvard Univ, Sch Med, Boston, MA 02115 USA. Brigham & Womens Hosp, Channing Lab, Boston, MA 02115 USA. : OXFORD UNIV PRESS INC. - 0027-8874 .- 1460-2105. ; 97:21, s. 1601-1608
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Journal article (peer-reviewed)abstract
- Background: Alcohol intake has been reported to be positively associated with an increased risk of postmenopausal breast cancer; however, the association with the estrogen receptor (ER) and progesterone receptor (PR) status of the breast tumors remains unclear. Methods: Self-reported data on alcohol consumption were collected in 1987 and 1997 from 51847 postmenopausal women in the population-based Swedish Mammography Cohort. Through June 30,2004,1188 invasive breast cancer case patients with known ER and PR status were identified during an average 8.3-year follow-up. We used Cox proportional hazards models to estimate multivariable relative risks (RRs) of breast cancer, adjusting for age; family history of breast cancer; body mass index; height; parity; age at menarche, first birth, and menopause; education level; use of postmenopausal hormones; and diet. Heterogeneity among groups was evaluated using the Wald test. All statistical tests were two-sided. Results: Alcohol consumption was associated with an increased risk for the development of ER-positive (+) tumors, irrespective of PR status (highest intake [ >= 10 g of alcohol per day] versus nondrinkers, multivariable RR = 1.35, 95% confidence interval [CI] = 1.02 to 1.80; P-trend < .049 for ER+PR+ tumors; and RR = 2.36, 95% CI = 1.56 to 3.56; P-trend < .001 for ER+PR-tumors). The absolute rate of ER+ breast cancer (standardized to the age distribution of person-years experienced by all study participants using 5-year age categories) was 232 per 100000 person-years among women in the highest category of alcohol intake, and 158 per 100000 person-years among nondrinkers. No association was observed between alcohol intake and the risk of developing ER-tumors. Furthermore, we observed a statistically significant interaction between alcohol intake and the use of postmenopausal hormones on the risk for ER+PR+ tumors (P-interaction = .039). Conclusion: The observed association between risk of developing postmenopausal ER+ breast cancer and alcohol drinking, especially among those women who use postmenopausal hormones, may be important, because the majority of breast tumors among postmenopausal women overexpress ER.
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