| 1. |
- Schael, S, et al.
(författare)
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Precision electroweak measurements on the Z resonance
- 2006
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Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
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Forskningsöversikt (refereegranskat)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. |
- Abbasi, R., et al.
(författare)
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The IceCube data acquisition system : Signal capture, digitization, and timestamping
- 2009
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 601:3, s. 294-316
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Tidskriftsartikel (refereegranskat)abstract
- IceCube is a km-scale neutrino observatory under construction at the South Pole with sensors both in the deep ice (InIce) and on the surface (IceTop). The sensors, called Digital Optical Modules (DOMs). detect, digitize and timestamp the signals from optical Cherenkov-radiation photons. The DOM Main Board (MB) data acquisition subsystem is connected to the central DAQ in the IceCube Laboratory (ICL) by a single twisted copper wire-pair and transmits packetized data on demand. Time calibration is maintained throughout the array by regular transmission to the DOMs of precisely timed analog signals, synchronized to a central GPS-disciplined clock. The design goals and consequent features, functional capabilities, and initial performance of the DOM MB, and the operation of a combined array of DOMs as a system, are described here. Experience with the first InIce strings and the IceTop stations indicates that the system design and performance goals have been achieved. (c) 2009 Elsevier B.V. All rights reserved.
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| 3. |
- Ackermann, M., et al.
(författare)
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Search for ultra-high-energy neutrinos with amanda-II
- 2008
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Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 675:2, s. 1014-1024
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Tidskriftsartikel (refereegranskat)abstract
- A search for diffuse neutrinos with energies in excess of 10(5) GeV is conducted with AMANDA-II data recorded between 2000 and 2002. Above 10(7) GeV, the Earth is essentially opaque to neutrinos. This fact, combined with the limited overburden of the AMANDA-II detector ( roughly 1.5 km), concentrates these ultra-high-energy neutrinos at the horizon. The primary background for this analysis is bundles of downgoing, high-energy muons from the interaction of cosmic rays in the atmosphere. No statistically significant excess above the expected background is seen in the data, and an upper limit is set on the diffuse all-flavor neutrino flux of E-2 Phi(90%CL) < 2.7x10(-7) GeV cm(-2) s(-1) sr(-1) valid over the energy range of 2x10(5) to 10(9) GeV. A number of models that predict neutrino fluxes from active galactic nuclei are excluded at the 90% confidence level.
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| 4. |
- Abbasi, R., et al.
(författare)
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Solar energetic particle spectrum on 2006 December 13 determined by IceTop
- 2008
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 689:1, s. L65-L68
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Tidskriftsartikel (refereegranskat)abstract
- On 2006 December 13 the IceTop air shower array at the South Pole detected a major solar particle event. By numerically simulating the response of the IceTop tanks, which are thick Cerenkov detectors with multiple thresholds deployed at high altitude with no geomagnetic cutoff, we determined the particle energy spectrum in the energy range 0.6-7.6 GeV. This is the first such spectral measurement using a single instrument with a well-defined viewing direction. We compare the IceTop spectrum and its time evolution with previously published results and outline plans for improved resolution of future solar particle spectra.
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| 5. |
- Abbasi, R., et al.
(författare)
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Search for point sources of high energy neutrinos with final data from AMANDA-II
- 2009
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Ingår i: Physical Review D. - 1550-7998 .- 1550-2368. ; 79, s. 062001-
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Tidskriftsartikel (refereegranskat)abstract
- We present a search for point sources of high energy neutrinos using 3.8 yr of data recorded by AMANDA-II during 2000-2006. After reconstructing muon tracks and applying selection criteria designed to optimally retain neutrino-induced events originating in the northern sky, we arrive at a sample of 6595 candidate events, predominantly from atmospheric neutrinos with primary energy 100 GeV to 8 TeV. Our search of this sample reveals no indications of a neutrino point source. We place the most stringent limits to date on E(-2) neutrino fluxes from points in the northern sky, with an average upper limit of E(2)Phi(nu mu)+nu(tau)<= 5.2x10(-11) TeV cm(-2) s(-1) on the sum of nu(mu) and nu(tau) fluxes, assumed equal, over the energy range from 1.9 TeV to 2.5 PeV.
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| 6. |
- Armesto, N., et al.
(författare)
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Heavy-ion collisions at the LHC-Last call for predictions
- 2008
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Ingår i: Journal of Physics G. - : IOP Publishing. - 0954-3899 .- 1361-6471. ; 35:5, s. 054001-
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Forskningsöversikt (refereegranskat)abstract
- This writeup is a compilation of the predictions for the forthcoming Heavy Ion Program at the Large Hadron Collider, as presented at the CERN Theory Institute 'Heavy Ion Collisions at the LHC - Last Call for Predictions', held from 14th May to 10th June 2007.
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| 7. |
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| 8. |
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| 9. |
- Gohritz, A, et al.
(författare)
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Ersatzoperationen bei Ausfall motorisher Funktionen an der Hand : Tendon transposition to restore muscle function in the hand
- 2007
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Ingår i: Der Unfallchirurg. - : Springer Science and Business Media LLC. - 0177-5537 .- 1433-044X. ; 110:9, s. 759-76
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Tidskriftsartikel (refereegranskat)abstract
- Nerve injuries in the upper extremity can result in severe disability. In the last three decades, progress in microsurgical techniques has improved the outcome for nerve injuries and if the prognosis is reasonably good, nerve repair should usually be performed prior to tendon transfer procedures. However, above all proximal lesions of peripheral nerves such as high radial nerve palsy still often yield unsatisfactory results, despite a technically well-executed nerve repair. Prognosis further depends on the time interval since the injury and also on the age of the patient, as the regenerative process is delayed in older patients. The indication for tendon transfers strongly depends on the personal and professional profiles of the individual patient. Tendon transfer procedures alleviate the suffering from functional hand impairment providing a superior alternative to permanent external splints. Tendon transfers are usually secondary procedures for replacing function after evaluation of the functional motor loss. Numerous transfer procedures have been described for every nerve trunk of the upper extremity, their prognosis depending mainly on the extent and pattern of nerve loss, local effects of the trauma (e.g. involvement of soft tissues, joints), and the physiological characteristics of the transferred muscle. Even if the results of the tendon transfers may finally be less satisfactory in cases of complex nerve damage than in isolated motor nerve lesions, they offer a valuable functional benefit, often being the only possibility to restore hand function. Although regrettably underused, tendon transfer improve upper extremity function in more than 70% of patients with cervical spinal cord injury. Reconstruction of key elements such as wrist extension, key grip between the thumb and the index finger, or digital flexion and extension leads to highly improved use of the tetraplegic hand and thus provides new mobility and independence from the help of others. This article presents an overview of the most common procedures to restore hand function in peripheral nerve injuries and tetraplegia in order to provide a systematic approach for decision making.
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| 10. |
- Gohritz, A., et al.
(författare)
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[Nerve and muscle transfer surgery to restore paralyzed elbow function]
- 2008
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Ingår i: Unfallchirurg. - : Springer Science and Business Media LLC. - 0177-5537. ; 111:2, s. 85-101
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Tidskriftsartikel (refereegranskat)abstract
- Paralysis of elbow flexion or extension leads to major impairment of upper extremity function. Surgical reconstruction can be achieved using several procedures.If the time interval since the nerve injury is short, anatomic reconstruction by means of nerve suture or nerve transplantation should be attempted. Alternatively, nerve transposition is possible. If more than 12-18 months have elapsed, reinnervation of arm muscles can no longer be expected. In this case, muscle transposition is helpful. Restoring flexion is predominantly required following brachial plexus injury, when the function of the biceps, brachioradialis and brachialis muscles are lost. As donor muscles the latissimus dorsi, pectoralis major and triceps brachii can be used, alternatively a transfer of the flexor-pronator muscles of the forearm is possible. Latissimus dorsi transfer to reconstruct elbow flexion is also indicated in defects of the anterior upper arm muscle compartiment due to trauma, ischemia, or tumor. Patients with proximal radial nerve lesions may benefit from latissimus transfer to reachieve elbow flexion extension.In tetraplegic patients, elbow extension is restored mainly by transfer of the posterior deltoid muscle extended with a tendon graft, or by means of a biceps-to-triceps transfer.
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