1. |
- 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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2. |
- Muysoms, F. E., et al.
(author)
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Classification of primary and incisional abdominal wall hernias
- 2009
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In: Hernia. - : Springer Science and Business Media LLC. - 1265-4906 .- 1248-9204. ; 13:4, s. 407-414
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Conference paper (peer-reviewed)abstract
- A classification for primary and incisional abdominal wall hernias is needed to allow comparison of publications and future studies on these hernias. It is important to know whether the populations described in different studies are comparable. Several members of the EHS board and some invitees gathered for 2 days to discuss the development of an EHS classification for primary and incisional abdominal wall hernias. To distinguish primary and incisional abdominal wall hernias, a separate classification based on localisation and size as the major risk factors was proposed. Further data are needed to define the optimal size variable for classification of incisional hernias in order to distinguish subgroups with differences in outcome. A classification for primary abdominal wall hernias and a division into subgroups for incisional abdominal wall hernias, concerning the localisation of the hernia, was formulated.
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3. |
- Simons, M P, et al.
(author)
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European Hernia Society guidelines on the treatment of inguinal hernia in adult patients.
- 2009
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In: Hernia. - : Springer. - 1265-4906 .- 1248-9204. ; 13:4, s. 343-403
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Journal article (peer-reviewed)abstract
- The European Hernia Society (EHS) is proud to present the EHS Guidelines for the Treatment of Inguinal Hernia in Adult Patients. The Guidelines contain recommendations for the treatment of inguinal hernia from diagnosis till aftercare. They have been developed by a Working Group consisting of expert surgeons with representatives of 14 country members of the EHS. They are evidence-based and, when necessary, a consensus was reached among all members. The Guidelines have been reviewed by a Steering Committee. Before finalisation, feedback from different national hernia societies was obtained. The Appraisal of Guidelines for REsearch and Evaluation (AGREE) instrument was used by the Cochrane Association to validate the Guidelines. The Guidelines can be used to adjust local protocols, for training purposes and quality control. They will be revised in 2012 in order to keep them updated. In between revisions, it is the intention of the Working Group to provide every year, during the EHS annual congress, a short update of new high-level evidence (randomised controlled trials [RCTs] and meta-analyses). Developing guidelines leads to questions that remain to be answered by specific research. Therefore, we provide recommendations for further research that can be performed to raise the level of evidence concerning certain aspects of inguinal hernia treatment. In addition, a short summary, specifically for the general practitioner, is given. In order to increase the practical use of the Guidelines by consultants and residents, more details on the most important surgical techniques, local infiltration anaesthesia and a patient information sheet is provided. The most important challenge now will be the implementation of the Guidelines in daily surgical practice. This remains an important task for the EHS. The establishment of an EHS school for teaching inguinal hernia repair surgical techniques, including tips and tricks from experts to overcome the learning curve (especially in endoscopic repair), will be the next step. Working together on this project was a great learning experience, and it was worthwhile and fun. Cultural differences between members were easily overcome by educating each other, respecting different views and always coming back to the principles of evidence-based medicine. The members of the Working Group would like to thank the EHS board for their support and especially Ethicon for sponsoring the many meetings that were needed to finalise such an ambitious project.
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4. |
- Tomasi, C., et al.
(author)
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Aerosols in polar regions : A historical overview based on optical depth and in situ observations
- 2007
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In: Journal of Geophysical Research. - 0148-0227 .- 2156-2202. ; 112:D16, s. D16205-
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Research review (peer-reviewed)abstract
- Large sets of filtered actinometer, filtered pyrheliometer and Sun photometer measurements have been carried out over the past 30 years by various groups at different Arctic and Antarctic sites and for different time periods. They were examined to estimate ensemble average, long-term trends of the summer background aerosol optical depth AOD(500 nm) in the polar regions ( omitting the data influenced by Arctic haze and volcanic eruptions). The trend for the Arctic was estimated to be between -1.6% and -2.0% per year over 30 years, depending on location. No significant trend was observed for Antarctica. The time patterns of AOD( 500 nm) and angstrom ngstrom's parameters a and beta measured with Sun photometers during the last 20 years at various Arctic and Antarctic sites are also presented. They give a measure of the large variations of these parameters due to El Chichon, Pinatubo, and Cerro Hudson volcanic particles, Arctic haze episodes most frequent in winter and spring, and the transport of Asian dust and boreal smokes to the Arctic region. Evidence is also shown of marked differences between the aerosol optical parameters measured at coastal and high-altitude sites in Antarctica. In situ optical and chemical composition parameters of aerosol particles measured at Arctic and Antarctic sites are also examined to achieve more complete information on the multimodal size distribution shape parameters and their radiative properties. A characterization of aerosol radiative parameters is also defined by plotting the daily mean values of a as a function of AOD( 500 nm), separately for the two polar regions, allowing the identification of different clusters related to fifteen aerosol classes, for which the spectral values of complex refractive index and single scattering albedo were evaluated.
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