| 1. |
- Schael, S, et al.
(författare)
-
Precision electroweak measurements on the Z resonance
- 2006
-
Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
-
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.
|
|
| 2. |
|
|
| 3. |
- Rondonotti, E, et al.
(författare)
-
Small-bowel neoplasms in patients undergoing video capsule endoscopy: a multicenter European study
- 2008
-
Ingår i: Endoscopy. - : Georg Thieme Verlag KG. - 1438-8812 .- 0013-726X. ; 40:6, s. 488-495
-
Tidskriftsartikel (refereegranskat)abstract
- Background and study aim: Small-bowel tumors account for 1%-3% of all gastrointestinal neoplasms. Recent studies with video capsule endoscopy (VCE) suggest that the frequency of these tumors may be substantially higher than previously reported. The aim of the study was to evaluate the frequency, clinical presentation, diagnostic/therapeutic work-up, and endoscopic appearance of small-bowel tumors in a large population of patients undergoing VCE. Patients and methods: Identification by a questionnaire of patients with VCE findings suggesting small-bowel tumors and histological confirmation of the neoplasm seen in 29 centers of 10 European Countries. Results: Of 5129 patients undergoing VCE, 124 (2.4%) had small-bowel tumors (112 primary, 12 metastatic). Among these patients, indications for VCE were: obscure gastrointestinal bleeding (108 patients), abdominal pain (9), search for primary neoplasm (6), diarrhea with malabsorption (1). The main primary small-bowel tumor type was gastrointestinal stromal tumor (GIST) (32%) followed by adenocarcinoma (20%) and carcinoid (15%); 66% of secondary small-bowel tumors were melanomas. Of the tumors, 80.6% were identified solely on the basis of VCE findings. 55 patients underwent WE as the third procedure after negative bidirectional endoscopy. The lesions were single in 89.5 % of cases, and multiple in 10.5%. Retention of the capsule occurred in 9.8% of patients with small-bowel tumors. After VICE, 54/124 patients underwent 57 other examinations before treatment; in these patients enteroscopy, when performed, showed a high diagnostic yield. Treatment was surgery in 95% of cases. Conclusions: Our data suggest that VCE detects small-bowel tumors in a small proportion of patients undergoing this examination, but the early use of this tool can shorten the diagnostic workup and influence the subsequent management of these patients.
|
|
| 4. |
- Antzutkin, Oleg, et al.
(författare)
-
Binding of Aluminium(III)-Citrate Complexes, [Al3(H-1Cit)3(OH)]-4 and [Al3(H-1Cit)3(OH)4]-7, to Alzheimer's A-beta(1-40) Peptides : In situ Atomic Force, Electron Microscopy and Solid State 13C and 27Al NMR Studies
- 2005
-
Ingår i: Sixth Keele Meeting on Aluminium. - : Centro de Estudos do Ambiente e Mar, Universidade de Aveiro. ; , s. 16-
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- It is believed that Alzheimer's disease (AD) amyloid-β-peptide (Aβ) deposits contribute directly to the disease's progressive neurodegeneration. Aggregation cascade for Aβ peptides, its relevance to neurotoxicity in the course of AD, various factors modulating Aβ aggregation kinetics and experimental methods useful for these studies were recently discussed [1]. Al(III), Zn(II), Cu(II) and Fe(III) ions are often colocalized at the center of the core of Alzheimer's amyloid plaques [2] and are suggested to promote aggregation of physiological concentrations of Aβ [3]. It has also been suggested that Al can block calcium permeable putative Aβ-peptide channels in bilayer membranes [4]. Therefore studies of complexation of metal ions with Aβ-oligomers and fibrils are important in the search for the causes of and potential treatments for AD.We studied effects of highly soluble and biologically relevant aluminium(III)-citrate compounds, [Al3(H-1Cit)3(OH)]-4 and [Al3(H-1Cit)3(OH)4]-7, on the fibrillogenesis of Aβ(1-40). All resonances in 156.37 MHz 27Al and 90.52 MHz 13C MAS NMR spectra of powder Al(III)-citrate complexes were assigned. 27Al MAS NMR of dialysed samples of Aβ(1-40) co-incubated with the Al(III)-citrate complexes at different concentrations in TRIS buffer solutions, pH 7.4, shows that Al(III)-citrates bind to Aβ(1-40) as [Al3(H-1Cit)3(OH)]-4 and either accelerate ([Al3(H-1Cit)3(OH)]-4 complex) or retard ([Al3(H-1Cit)3(OH)4]-7 compound) aggregation of Aβ(1-40) as revealed by AFM. [1] ON Antzutkin, Magn. Reson. Chem. 42 (2004) 231; [2] MA Lovell et al., J. Neurol. Sci. 158 (1998) 47; Ch Exley et al., Al and Alzheimer's disease, Ch Exley (Ed)1998) 47; Ch Exley , Ch Exley (Ed) Elsevier Science, 2001, 421; [3] PW Mantyh et al., J. Neurochem. 61 (1993) 1171; [4] N Arispe et al, PNAS 90 (1993) 567.
|
|
| 5. |
|
|
| 6. |
|
|
