81 research outputs found
Low prevalence of Chlamydia trachomatis infection in asymptomatic young Swiss men
BACKGROUND: Prevalence and risk factors for Chlamydia trachomatis infection among young men in Switzerland is still unknown. The objective of the present study was to assess prevalence and risk factors for C. trachomatis infection in young Swiss men. METHODS: 517 young Swiss men were enrolled in this cross-sectional study during their compulsory military recruitment. Participants completed a questionnaire and gave urine samples which were screened for C. trachomatis DNA by PCR. Genotyping of positive samples was done by amplification and sequencing the ompA gene. RESULTS: The prevalence of chlamydial infection among young Swiss male was 1.2% (95% confidence interval [95%CI], 0.4-2.5%). C. trachomatis infection was only identified among the 306 men having multiple sexual partner. Although frequent, neither unprotected sex (absence of condom use), nor alcohol and drug abuse were associated with chlamydial infection. Men living in cities were more frequently infected (2.9%, 95%CI 0.8-7.4%) than men living in rural areas (0.5%, 95%CI 0.1-1.9%, p = 0.046). Moreover, naturalised Swiss citizens were more often positive (4.9%, 95%CI 1.3-12.5%) than native-born Swiss men (0.5%, 95%CI 0.1-1.7%, p = 0.003). CONCLUSION: In comparison with other countries, the prevalence of chlamydial infection in men is extremely low in Switzerland, despite a significant prevalence of risky sexual behaviour. C. trachomatis infection was especially prevalent in men with multiple sexual partners. Further research is required (i) to define which subgroup of the general population should be routinely screened, and (ii) to test whether such a targeted screening strategy will be effective to reduce the prevalence of chlamydial infection among this population
LocaliteÌs distribueÌes, globaliteÌs localiseÌes : actions, actants et meÌdiations au service de lâethnographie du numeÌrique
Sâappuyant sur trois enqueÌtes de terrain qui portent sur le façonnage dâeÌtres numeÌriques (algorithmes, bases de donneÌes, objets numeÌriseÌs), le preÌsent article traite des relectures meÌthodologiques que lâon peut faire de trois contributions de Latour aÌ lâenqueÌte ethnographique. 1. Il montre que lâaccent mis sur les seÌquences dâaction permet dâengager une enqueÌte systeÌmatique qui rend compte de trajectoires. 2. Il avance que le concept dâactant sensibilise aÌ lâeÌventail des entiteÌs agissantes qui infleÌchissent ces trajectoires, de meÌme quâau peuplement de situations apparemment inoccupeÌes. 3. Il soutient que les concepts dâassociation, de traduction et de meÌdiation permettent de connecter diffeÌrentes situations et actions localiseÌes. Ultimement, ces trois apports eÌclairent les agencements et les reÌagencements
Species-Specific Recognition of Aspergillus fumigatus by Toll-like Receptor 1 and Toll-like Receptor 6
Background.âAspergillus fumigatus causes invasive aspergillosis, a potentially fatal infection in oncohematological patients. Innate immune detection of A. fumigatus involves Toll-like receptor (TLR) 4 and TLR2, which forms a heterodimer with either TLR1 or TLR6. The role of those coreceptors in Aspergillus sensing is unknown. Methods.âCytokine production was measured in bone marrow-derived macrophages (BMDMs) from wild-type (WT) and TLR-deficient mice after incubation with a WT and an immunogenic RodA-deficient (ÎrodA-47) strain of A. fumigatus and in lungs from these mice after intranasal mold inoculation. Aspergillus fumigatus-mediated NF-ÎșB activation was measured in HEK293T cells transfected with plasmids expressing mouse or human TLRs. Results.âBone marrow-derived macrophages from TLR1- and TLR6-deficient mice produced lower amounts of interleukin 12p40, CXCL2, interleukin 6, and tumor necrosis factor α than BMDMs from WT mice after stimulation with A. fumigatus. Lungs from TLR1- and TLR6-deficient mice had diminished CXCL1 and CXCL2 production and increased fungal burden after intranasal inoculation of ÎrodA A. fumigatus compared with lungs from WT mice. ÎrodA strain-mediated NF-ÎșB activation was observed in HEK293T cells expressing mouse TLR2/1, mouse TLR2/6, and human TLR2/1 but not human TLR2/6. Conclusions.âInnate immune detection of A. fumigatus is mediated by TLR4 and TLR2 together with TLR1 or TLR6 in mice and TLR1 but not TLR6 in human
Predicting Venous Thromboembolic Events in Patients with Coronavirus Disease 2019 Requiring Hospitalization: an Observational Retrospective Study by the COVIDIC Initiative in a Swiss University Hospital.
Coronavirus disease 2019 (COVID-19) can result in profound changes in blood coagulation. The aim of the study was to determine the incidence and predictors of venous thromboembolic events (VTE) among patients with COVID-19 requiring hospital admission. Subjects and Methods. We performed a retrospective study at the Lausanne University Hospital with patients admitted because of COVID-19 from February 28 to April 30, 2020.
Among 443 patients with COVID-19, VTE was diagnosed in 41 patients (9.3%; 27 pulmonary embolisms, 12 deep vein thrombosis, one pulmonary embolism and deep vein thrombosis, one portal vein thrombosis). VTE was diagnosed already upon admission in 14 (34.1%) patients and 27 (65.9%) during hospital stay (18 in ICU and nine in wards outside the ICU). Multivariate analysis revealed D-dimer value > 3,120 ng/ml (P < 0.001; OR 15.8, 95% CI 4.7-52.9) and duration of 8 days or more from COVID-19 symptoms onset to presentation (P 0.020; OR 4.8, 95% CI 1.3-18.3) to be independently associated with VTE upon admission. D-dimer value â„ 3,000 ng/l combined with a Wells score for PE â„ 2 was highly specific (sensitivity 57.1%, specificity 91.6%) in detecting VTE upon admission. Development of VTE during hospitalization was independently associated with D-dimer value > 5,611 ng/ml (P < 0.001; OR 6.3, 95% CI 2.4-16.2) and mechanical ventilation (P < 0.001; OR 5.9, 95% CI 2.3-15.1).
VTE seems to be a common COVID-19 complication upon admission and during hospitalization, especially in ICU. The combination of Wells â„ 2 score and D - dimer â„ 3,000 ng/l is a good predictor of VTE at admission
A study of CP violation in B-+/- -> DK +/- and B-+/- -> D pi(+/-) decays with D -> (KSK +/-)-K-0 pi(-/+) final states
A first study of CP violation in the decay modes and , where labels a or meson and labels a or meson, is performed. The analysis uses the LHCb data set collected in collisions, corresponding to an integrated luminosity of 3 fb. The analysis is sensitive to the CP-violating CKM phase through seven observables: one charge asymmetry in each of the four modes and three ratios of the charge-integrated yields. The results are consistent with measurements of using other decay modes
Measurement of the (eta c)(1S) production cross-section in proton-proton collisions via the decay (eta c)(1S) -> p(p)over-bar
The production of the state in proton-proton collisions is probed via its decay to the final state with the LHCb detector, in the rapidity range GeV/c. The cross-section for prompt production of mesons relative to the prompt cross-section is measured, for the first time, to be at a centre-of-mass energy TeV using data corresponding to an integrated luminosity of 0.7 fb, and at TeV using 2.0 fb. The uncertainties quoted are, in order, statistical, systematic, and that on the ratio of branching fractions of the and decays to the final state. In addition, the inclusive branching fraction of -hadron decays into mesons is measured, for the first time, to be , where the third uncertainty includes also the uncertainty on the inclusive branching fraction from -hadron decays. The difference between the and meson masses is determined to be MeV/c.The production of the state in proton-proton collisions is probed via its decay to the final state with the LHCb detector, in the rapidity range . The cross-section for prompt production of mesons relative to the prompt cross-section is measured, for the first time, to be at a centre-of-mass energy using data corresponding to an integrated luminosity of 0.7Â fb , and at using 2.0Â fb . The uncertainties quoted are, in order, statistical, systematic, and that on the ratio of branching fractions of the and decays to the final state. In addition, the inclusive branching fraction of -hadron decays into mesons is measured, for the first time, to be , where the third uncertainty includes also the uncertainty on the inclusive branching fraction from -hadron decays. The difference between the and meson masses is determined to be .The production of the state in proton-proton collisions is probed via its decay to the final state with the LHCb detector, in the rapidity range GeV/c. The cross-section for prompt production of mesons relative to the prompt cross-section is measured, for the first time, to be at a centre-of-mass energy TeV using data corresponding to an integrated luminosity of 0.7 fb, and at TeV using 2.0 fb. The uncertainties quoted are, in order, statistical, systematic, and that on the ratio of branching fractions of the and decays to the final state. In addition, the inclusive branching fraction of -hadron decays into mesons is measured, for the first time, to be , where the third uncertainty includes also the uncertainty on the inclusive branching fraction from -hadron decays. The difference between the and meson masses is determined to be MeV/c
Search for the lepton flavour violating decay tau(-) -> mu(-)mu(+)mu(-)
A search for the lepton flavour violating decay is performed with the LHCb experiment. The data sample corresponds to an integrated luminosity of 1.0 fb of proton-proton collisions at a centre-of-mass energy of 7 TeV and 2.0 fb at 8 TeV. No evidence is found for a signal, and a limit is set at 90% confidence level on the branching fraction, .A search for the lepton flavour violating decay Ï â ÎŒ ÎŒ ÎŒ is performed with the LHCb experiment. The data sample corresponds to an integrated luminosity of 1.0 fb of proton-proton collisions at a centre-of-mass energy of 7 TeV and 2.0 fb at 8 TeV. No evidence is found for a signal, and a limit is set at 90% confidence level on the branching fraction, .A search for the lepton flavour violating decay is performed with the LHCb experiment. The data sample corresponds to an integrated luminosity of of proton-proton collisions at a centre-of-mass energy of and at . No evidence is found for a signal, and a limit is set at confidence level on the branching fraction,
Measurement of the CP-violating phase in decays and limits on penguin effects
Time-dependent CP violation is measured in the channel for each resonant final state using data collected with an integrated luminosity of 3.0 fb in collisions using the LHCb detector. The final state with the largest rate, , is used to measure the CP-violating angle to be . This result can be used to limit the size of penguin amplitude contributions to CP violation measurements in, for example, decays. Assuming approximate SU(3) flavour symmetry and neglecting higher order diagrams, the shift in the CP-violating phase is limited to be within the interval [, +] at 95% confidence level. Changes to the limit due to SU(3) symmetry breaking effects are also discussed.Time-dependent CP violation is measured in the B(âââ)0âJ/ÏÏ+Ïâ channel for each Ï+Ïâ resonant final state using data collected with an integrated luminosity of 3.0 fb â1 in pp collisions using the LHCb detector. The final state with the largest rate, J/ÏÏ0(770) , is used to measure the CP -violating angle 2ÎČeff to be (41.7±9.6â6.3+2.8)° . This result can be used to limit the size of penguin amplitude contributions to CP violation measurements in, for example, B(âââ)s0âJ/ÏÏ decays. Assuming approximate SU(3) flavour symmetry and neglecting higher order diagrams, the shift in the CP -violating phase Ïs is limited to be within the interval [ â1.05°,+1.18° ] at 95% confidence level. Changes to the limit due to SU(3) symmetry breaking effects are also discussed.Time-dependent CP violation is measured in the channel for each resonant final state using data collected with an integrated luminosity of 3.0 fb in collisions using the LHCb detector. The final state with the largest rate, , is used to measure the CP-violating angle to be . This result can be used to limit the size of penguin amplitude contributions to CP violation measurements in, for example, decays. Assuming approximate SU(3) flavour symmetry and neglecting higher order diagrams, the shift in the CP-violating phase is limited to be within the interval [, +] at 95% confidence level. Changes to the limit due to SU(3) symmetry breaking effects are also discussed.Time-dependent CP violation is measured in the B0âJ/ÏÏ+Ïâ channel for each Ï+Ïâ resonant final state using data collected with an integrated luminosity of 3.0 fb â1 in pp collisions using the LHCb detector. The final state with the largest rate, J/ÏÏ0(770) , is used to measure the CP -violating angle 2ÎČeff to be (41.7±9.6â6.3+2.8)° . This result can be used to limit the size of penguin amplitude contributions to CP violation measurements in, for example, Bs0âJ/ÏÏ decays. Assuming approximate SU(3) flavour symmetry and neglecting higher order diagrams, the shift in the CP -violating phase Ïs is limited to be within the interval [ â1.05°,+1.18° ] at 95% confidence level. Changes to the limit due to SU(3) symmetry breaking effects are also discussed
Study of forward Z + jet production in pp collisions at âs=7 TeV
A measurement of the +jet production cross-section in collisions at a centre-of-mass energy TeV is presented. The analysis is based on an integrated luminosity of recorded by the LHCb experiment. Results are shown with two jet transverse momentum thresholds, 10 and 20 GeV, for both the overall cross-section within the fiducial volume, and for six differential cross-section measurements. The fiducial volume requires that both the jet and the muons from the Z boson decay are produced in the forward direction (). The results show good agreement with theoretical predictions at the second-order expansion in the coupling of the strong interaction.A measurement of the +jet production cross-section in collisions at a centre-of-mass energy TeV is presented. The analysis is based on an integrated luminosity of recorded by the LHCb experiment. Results are shown with two jet transverse momentum thresholds, 10 and 20 GeV, for both the overall cross-section within the fiducial volume, and for six differential cross-section measurements. The fiducial volume requires that both the jet and the muons from the Z boson decay are produced in the forward direction (). The results show good agreement with theoretical predictions at the second-order expansion in the coupling of the strong interaction
Measurement of the lifetime of the meson using the decay mode
The difference in total widths between the and mesons is measured using 3.0fb of data collected by the LHCb experiment in 7 and 8 TeV centre-of-mass energy proton-proton collisions at the LHC. Through the study of the time evolution of and decays, the width difference is measured to be where the first uncertainty is statistical and the second systematic. The known lifetime of the meson is used to convert this to a precise measurement of the lifetime, where the first uncertainty is statistical and the second systematic.The difference in total widths between the B+ c and B+ mesons is measured using 3.0 fbâ1 of data collected by the LHCb experiment in 7 and 8 TeV centre-of-mass energy proton-proton collisions at the LHC. Through the study of the time evolution of B+ c â J/ÏÏ+ and B+ â J/ÏK+ decays, the width difference is measured to be âΠ⥠ÎB + c â ÎB+ = 4.46 ± 0.14 ± 0.07 mmâ1 c, where the first uncertainty is statistical and the second systematic. The known lifetime of the B+ meson is used to convert this to a precise measurement of the B+ c lifetime, ÏB + c = 513.4 ± 11.0 ± 5.7 fs, where the first uncertainty is statistical and the second systematic.The difference in total widths between the Bc+ and B+ mesons is measured using a data sample corresponding to an integrated luminosity of 3.0 fbâ1 collected by the LHCb experiment in 7 and 8 TeV centre-of-mass energy protonâproton collisions at the LHC. Through the study of the time evolution of Bc+âJ/ÏÏ+ and B+âJ/ÏK+ decays, the width difference is measured to be ÎÎâĄÎBc+âÎB+=4.46±0.14±0.07 mmâ1c, where the first uncertainty is statistical and the second systematic. The known lifetime of the B+ meson is used to convert this to a precise measurement of the Bc+ lifetime, ÏBc+=513.4±11.0±5.7 fs, where the first uncertainty is statistical and the second is systematic.The difference in total widths between the Bc+ and B+ mesons is measured using a data sample corresponding to an integrated luminosity of 3.0 fbâ1 collected by the LHCb experiment in 7 and 8 TeV centre-of-mass energy protonâproton collisions at the LHC. Through the study of the time evolution of Bc+âJ/ÏÏ+ and B+âJ/ÏK+ decays, the width difference is measured to be ÎÎâĄÎBc+âÎB+=4.46±0.14±0.07 mmâ1c, where the first uncertainty is statistical and the second systematic. The known lifetime of the B+ meson is used to convert this to a precise measurement of the Bc+ lifetime, ÏBc+=513.4±11.0±5.7 fs, where the first uncertainty is statistical and the second is systematic
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