| 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. |
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| 3. |
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| 4. |
- Abdesselam, A., et al.
(författare)
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Engineering for the ATLAS SemiConductor Tracker (SCT) end-cap
- 2008
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Ingår i: Journal of Instrumentation. - 1748-0221. ; 3
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Tidskriftsartikel (refereegranskat)abstract
- The ATLAS SemiConductor Tracker (SCT) is a silicon-strip tracking detector which forms part of the ATLAS inner detector. The SCT is designed to track charged particles produced in proton-proton collisions at the Large Hadron Collider (LHC) at CERN at an energy of 14 TeV. The tracker is made up of a central barrel and two identical end-caps. The barrel contains 2112 silicon modules, while each end-cap contains 988 modules. The overall tracking performance depends not only on the intrinsic measurement precision of the modules but also on the characteristics of the whole assembly, in particular, the stability and the total material budget. This paper describes the engineering design and construction of the SCT end-caps, which are required to support mechanically the silicon modules, supply services to them and provide a suitable environment within the inner detector. Critical engineering choices are highlighted and innovative solutions are presented - these will be of interest to other builders of large-scale tracking detectors. The SCT end-caps will be fully connected at the start of 2008. Further commissioning will continue, to be ready for proton-proton collision data in 2008.
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| 5. |
- Abdallah, J, et al.
(författare)
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Photon events with missing energy in e(+)e(-) collisions at root s=130 to 209 GeV
- 2005
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 38:4, s. 395-411
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Tidskriftsartikel (refereegranskat)abstract
- The production of single- and multi-photon events has been studied in the reaction e(+) e(-) --> gamma(gamma) + invisible particles. The data collected with the DELPHI detector during the years 1999 and 2000 at centre-of-mass energies between 191 GeV and 209 GeV was combined with earlier data to search for phenomena beyond the Standard Model. The measured number of light neutrino families was consistent with three and the absence of an excess of events beyond that predicted by the Standard Model processes was used to set limits on new physics. Both model-independent searches and searches for new processes predicted by supersymmetric and extra-dimensional models have been made. Limits on new non-standard model interactions between neutrinos and electrons were also determined.
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| 6. |
- Abdesselam, A., et al.
(författare)
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The ATLAS semiconductor tracker end-cap module
- 2007
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 575:3, s. 353-389
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Tidskriftsartikel (refereegranskat)abstract
- The challenges for the tracking detector systems at the LHC are unprecedented in terms of the number of channels, the required read-out speed and the expected radiation levels. The ATLAS Semiconductor Tracker. (SCT) end-caps have a total of about 3 million electronics channels each reading out every 25 ns into its own on-chip 3.3 mu s buffer. The highest anticipated dose after 10 years operation is 1.4x10(14) cm(-2) in units of 1 MeV neutron equivalent (assuming the damage factors scale with the non-ionising energy loss). The forward tracker has 1976 double-sided modules, mostly of area similar to 70 cm(2), each having 2 x 768 strips read out by six ASICs per side. The requirement to achieve an average perpendicular radiation length of 1.5% X-0, while coping with up to 7 W dissipation per module (after irradiation), leads to stringent constraints on the thermal design. The additional requirement of 1500e(-) equivalent noise charge (ENC) rising to only 1800e(-) ENC after irradiation, provides stringent design constraints on both the high-density Cu/Polyimide flex read-out circuit and the ABCD3TA read-out ASICs. Finally, the accuracy of module assembly must not compromise the 16 mu m (r phi) resolution perpendicular to the strip directions or 580 mu m radial resolution coming from the 40 mrad front-back stereo angle. A total of 2210 modules were built to the tight tolerances and specifications required for the SCT. This was 234 more than the 1976 required and represents a yield of 93%. The component flow was at times tight, but the module production rate of 40-50 per week was maintained despite this. The distributed production was not found to be a major logistical problem and it allowed additional flexibility to take advantage of where the effort was available, including any spare capacity, for building the end-cap modules. The collaboration that produced the ATLAS SCT end-cap modules kept in close contact at all times so that the effects of shortages or stoppages at different sites could be rapidly resolved.
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| 7. |
- Abate, E., et al.
(författare)
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Combined performance tests before installation of the ATLAS Semiconductor and Transition Radiation Tracking Detectors
- 2008
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Ingår i: Journal of Instrumentation. - 1748-0221. ; 3
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Tidskriftsartikel (refereegranskat)abstract
- The ATLAS (A Toroidal LHC ApparatuS) Inner Detector provides charged particle tracking in the centre of the ATLAS experiment at the Large Hadron Collider (LHC). The Inner Detector consists of three subdetectors: the Pixel Detector, the Semiconductor Tracker (SCT), and the Transition Radiation Tracker (TRT). This paper summarizes the tests that were carried out at the final stage of SCT+TRT integration prior to their installation in ATLAS. The combined operation and performance of the SCT and TRT barrel and endcap detectors was investigated through a series of noise tests, and by recording the tracks of cosmic rays. This was a crucial test of hardware and software of the combined tracker detector systems. The results of noise and cross-talk tests on the SCT and TRT in their final assembled configuration, using final readout and supply hardware and software, are reported. The reconstruction and analysis of the recorded cosmic tracks allowed testing of the offline analysis chain and verification of basic tracker performance parameters, such as efficiency and spatial resolution, in combined operation before installation.
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| 8. |
- Abdesselam, A., et al.
(författare)
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The barrel modules of the ATLAS semiconductor tracker
- 2006
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 568:2, s. 642-671
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Tidskriftsartikel (refereegranskat)abstract
- This paper describes the silicon microstrip modules in the barrel section of the SemiConductor Tracker (SCT) of the ATLAS experiment at the CERN Large Hadron Collider (LHC). The module requirements, components and assembly techniques are given, as well as first results of the module performance on the fully assembled barrels that make up the detector being installed in the ATLAS experiment.
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| 9. |
- Abat, E., et al.
(författare)
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Study of the response of the ATLAS central calorimeter to pions of energies from 3 to 9 GeV
- 2009
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Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002 .- 1872-9576. ; 607:2, s. 372-386
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Tidskriftsartikel (refereegranskat)abstract
- A fully instrumented slice of the ATLAS central detector was exposed to test beams from the SPS (Super Proton Synchrotron) at CERN in 2004. in this paper, the response of the central calorimeters to pions with energies in the range between 3 and 9 GeV is presented. The linearity and the resolution of the combined calorimetry (electromagnetic and hadronic calorimeters) was measured and compared to the prediction of a detector simulation program using the toolkit Geant 4. (C) 2009 Elsevier B.V. All rights reserved.
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| 10. |
- Pittori, C., et al.
(författare)
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First AGILE catalog of high-confidence gamma-ray sources
- 2009
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 506:3, s. 1563-1574
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Tidskriftsartikel (refereegranskat)abstract
- We present the first catalog of high-confidence gamma-ray sources detected by the AGILE satellite during observations performed from July 9, 2007 to June 30, 2008. Cataloged sources were detected by merging all the available data over the entire time period. AGILE, launched in April 2007, is an ASI mission devoted to gamma-ray observations in the 30 MeV-50 GeV energy range, with simultaneous X-ray imaging capability in the 18-60 keV band. This catalog is based on Gamma-Ray Imaging Detector (GRID) data for energies greater than 100 MeV. For the first AGILE catalog, we adopted a conservative analysis, with a high-quality event filter optimized to select gamma-ray events within the central zone of the instrument field of view (radius of 40 degrees). This is a significance-limited (4 sigma) catalog, and it is not a complete flux-limited sample due to the non-uniform first-year AGILE sky coverage. The catalog includes 47 sources, 21 of which are associated with confirmed or candidate pulsars, 13 with blazars (7 FSRQ, 4 BL Lacs, 2 unknown type), 2 with HMXRBs, 2 with SNRs, 1 with a colliding-wind binary system, and 8 with unidentified sources.
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| 11. |
- Donnarumma, I., et al.
(författare)
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Multiwavelength Observations of 3C 454.3. II. The AGILE 2007 December Campaign
- 2009
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Ingår i: Astrophysical Journal Letters. - 2041-8205. ; 707:2, s. 1115-1123
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Tidskriftsartikel (refereegranskat)abstract
- We report on the second Astrorivelatore Gamma a Immagini Leggero (AGILE) multiwavelength campaign of the blazar 3C 454.3 during the first half of 2007 December. This campaign involved AGILE, Spitzer, Swift, Suzaku, the Whole Earth Blazar Telescope (WEBT) consortium, the Rapid Eye Mount (REM), and the Multicolor Imaging Telescopes for Survey and Monstrous Explosions (MITSuME) telescopes, offering a broadband coverage that allowed for a simultaneous sampling of the synchrotron and inverse Compton (IC) emissions. The two-week AGILE monitoring was accompanied by radio to optical monitoring by WEBT and REM, and by sparse observations in mid-infrared and soft/ hard X-ray energy bands performed by means of Target of Opportunity observations by Spitzer, Swift, and Suzaku, respectively. The source was detected with an average flux of similar to 250 x 10(-8) photons cm(-2) s(-1) above 100 MeV, typical of its flaring states. The simultaneous optical and gamma-ray monitoring allowed us to study the time lag associated with the variability in the two energy bands, resulting in a possible <= one-day delay of the gamma-ray emission with respect to the optical one. From the simultaneous optical and gamma-ray fast flare detected on December 12, we can constrain the delay between the gamma-ray and optical emissions within 12 hr. Moreover, we obtain three spectral energy distributions (SEDs) with simultaneous data for 2007 December 5, 13, and 15, characterized by the widest multifrequency coverage. We found that a model with an external Compton on seed photons by a standard disk and reprocessed by the broad-line regions does not describe in a satisfactory way the SEDs of 2007 December 5, 13, and 15. An additional contribution, possibly from the hot corona with T = 10(6) K surrounding the jet, is required to account simultaneously for the softness of the synchrotron and the hardness of the IC emissions during those epochs.
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| 12. |
- Orfanos, P, et al.
(författare)
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Eating out of home and its correlates in 10 European countries. The European Prospective Investigation into Cancer and Nutrition (EPIC) study
- 2007
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Ingår i: Public Health Nutrition. - 1475-2727 .- 1368-9800. ; 10:12, s. 1515-1525
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To compare the average out-of-home (OH) consumption of foods and beverages, as well as energy intake, among populations from 10 European countries and to describe the characteristics of substantial OH eaters, as defined for the purpose of the present study, in comparison to other individuals. DESIGN: Cross-sectional study. Dietary data were collected through single 24-hour dietary recalls, in which the place of consumption was recorded. For the present study, substantial OH eaters were defined as those who consumed more than 25% of total daily energy intake at locations other than the household premises. Mean dietary intakes and the proportion of substantial OH eaters are presented by food group and country. Logistic regression analyses were used to estimate the odds of being a substantial OH eater in comparison to not being one, using mutually adjusted possible non-dietary determinants. SETTING: Ten European countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). SUBJECTS: The subjects were 34 270 individuals, 12 537 men and 21 733 women, aged 35-74 years. RESULTS: The fraction of energy intake during OH eating was generally higher in northern European countries than in the southern ones. Among the food and beverage groups, those selectively consumed outside the home were coffee/tea/waters and sweets and, to a lesser extent, cereals, meats, added lipids and vegetables. Substantial OH eating was positively associated with energy intake and inversely associated with age and physical activity. Substantial OH eating was less common among the less educated compared with the more educated, and more common during weekdays in central and north Europe and during the weekend in south Europe. CONCLUSIONS: Eating outside the home was associated with sedentary lifestyle and increased energy intake; it was more common among the young and concerned in particular coffee/tea/waters and sweets.
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| 13. |
- Al-Delaimy, WK, et al.
(författare)
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Plasma carotenoids as biomarkers of intake of fruits and vegetables: ecological-level correlations in the European Prospective Investigation into Cancer and Nutrition (EPIC)
- 2005
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Ingår i: European Journal of Clinical Nutrition. - : Springer Science and Business Media LLC. - 1476-5640 .- 0954-3007. ; 59:12, s. 1397-1408
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The aim of this study was to assess the ability of a single 24-h dietary recall (24HDR) and food questionnaires (FQ) to predict plasma carotenoid levels at the ecological level by assessing the relationship between mean plasma carotenoid levels and mean intake of fruit and vegetables measured by 24HDR and FQ across 16 European regions. Design: A random subsample of 3089 subjects was included, stratified by age and gender. They provided blood samples and dietary information between 1992 and 2000 as part of the European Prospective Investigation into Cancer and Nutrition. Results: Using Spearman's correlation coefficients, the correlations between mean regional 24HDR fruit and vegetable variables and corresponding mean plasma carotenoid levels were generally higher than the correlations using FQ means. The highest correlation was between the 24HDR citrus fruit variable and beta-cryptoxanthin (r = 0.90). For 24HDR, total fruits and vegetables were highly correlated with lutein, zeaxanthin, and beta-cryptoxanthin (r = 0.83-0.87), while vegetables were more closely related with lutein (r = 0.69) and zeaxanthin (r = 0.68), and fruits correlated with zeaxanthin (r = 0.87) and beta-cryptoxanthin (r = 0.84). Root vegetables (r = 0.81) and total carrots (r = 0.71) were well correlated with alpha-carotene. In the multivariate models adjusting for age, body mass index, and season, and using observations of means stratified by sex and region, the association was generally higher for 24HDR compared to FQ. Conclusion: Mean regional intakes of fruits and vegetables in several European countries were closely correlated with corresponding mean plasma levels of individual carotenoids. Fruits and vegetables measured by 24HDR were generally better able to predict plasma carotenoids at the ecological level.
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| 14. |
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| 15. |
- Jenab, M, et al.
(författare)
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Plasma and dietary carotenoid, retinol and tocopherol levels and the risk of gastric adenocarcinomas in the European prospective investigation into cancer and nutrition
- 2006
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Ingår i: British Journal of Cancer. - : Springer Science and Business Media LLC. - 1532-1827 .- 0007-0920. ; 95:3, s. 406-415
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Tidskriftsartikel (refereegranskat)abstract
- Despite declining incidence rates, gastric cancer (GC) is a major cause of death worldwide. Its aetiology may involve dietary antioxidant micronutrients such as carotenoids and tocopherols. The objective of this study was to determine the association of plasma levels of seven common carotenoids, their total plasma concentration, retinol and alpha- and gamma-tocopherol, with the risk of gastric adenocarcinoma in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC), a large cohort involving 10 countries. A secondary objective was to determine the association of total sum of carotenoids, retinol and alpha-tocopherol on GCs by anatomical subsite (cardia/noncardia) and histological subtype (diffuse/intestinal). Analytes were measured by high-performance liquid chromatography in prediagnostic plasma from 244 GC cases and 645 controls matched by age, gender, study centre and date of blood donation. Conditional logistic regression models adjusted by body mass index, total energy intake, smoking and Helicobacter pylori infection status were used to estimate relative cancer risks. After an average 3.2 years of follow-up, a negative association with GC risk was observed in the highest vs the lowest quartiles of plasma beta-cryptoxanthin (odds ratio (OR) = 0.53, 95% confidence intervals (CI) = 0.30-0.94, P(trend) = 0.006), zeaxanthin (OR = 0.39, 95% CI = 0.22-0.69, P(trend) = 0.005), retinol (OR = 0.55, 95% CI = 0.33-0.93, P(trend) = 0.005) and lipid-unadjusted alpha-tocopherol (OR = 0.59, 95% CI = 0.37-0.94, P(trend) = 0.022). For all analytes, no heterogeneity of risk estimates or significant associations were observed by anatomical subsite. In the diffuse histological subtype, an inverse association was observed with the highest vs lowest quartile of lipid-unadjusted alpha-tocopherol (OR = 0.26, 95% CI = 0.11-0.65, P(trend) = 0.003). These results show that higher plasma concentrations of some carotenoids, retinol and alpha-tocopherol are associated with reduced risk of GC.
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| 16. |
- van Bakel, M. M. E., et al.
(författare)
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Dietary glycaemic index and glycaemic load in the European Prospective Investigation into Cancer and Nutrition
- 2009
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Ingår i: European Journal of Clinical Nutrition. - : Springer Science and Business Media LLC. - 1476-5640 .- 0954-3007. ; 63:4s, s. 188-205
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: To describe dietary glycaemic index (GI) and glycaemic load (GL) values in the population participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) study according to food groups, nutrients and lifestyle characteristics. Methods: Single 24-h dietary recalls (24-HDRs) from 33 566 subjects were used to calculate dietary GI and GL, and an ad hoc database was created as the main reference source. Mean GI and GL intakes were adjusted for age, total energy intake, height and weight, and were weighted by season and day of recall. Results: GI was the lowest in Spain and Germany, and highest in the Netherlands, United Kingdom and Denmark for both genders. In men, GL was the lowest in Spain and Germany and highest in Italy, whereas in women, it was the lowest in Spain and Greece and highest in the UK health-conscious cohort. Bread was the largest contributor to GL in all centres (15-45%), but it also showed the largest inter-individual variation. GL, but not GI, tended to be lower in the highest body mass index category in both genders. GI was positively correlated with starch and intakes of bread and potatoes, whereas it was correlated negatively with intakes of sugar, fruit and dairy products. GL was positively correlated with all carbohydrate components and intakes of cereals, whereas it was negatively correlated with fat and alcohol and with intakes of wine, with large variations across countries. Conclusions: GI means varied modestly across countries and genders, whereas GL means varied more, but it may possibly act as a surrogate of carbohydrate intake. European Journal of Clinical Nutrition (2009) 63, S188-S205; doi: 10.1038/ejcn.2009.81
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| 17. |
- Al-Delaimy, WK, et al.
(författare)
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Plasma carotenoids as biomarkers of intake of fruits and vegetables: individual-level correlations in the European Prospective Investigation into Cancer and Nutrition (EPIC)
- 2005
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Ingår i: European Journal of Clinical Nutrition. - : Springer Science and Business Media LLC. - 1476-5640 .- 0954-3007. ; 59:12, s. 1387-1396
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The aim in this study was to assess the association between individual plasma carotenoid levels (alpha-carotene, beta-carotene, lycopene, beta-cryptoxanthin, lutein, zeaxanthin) and fruit and vegetable intakes recorded by a calibrated food questionnaire (FQ) and 24- h dietary recall records (24HDR) in nine different European countries with diverse populations and widely varying intakes of plant foods. Design: A stratified random subsample of 3089 men and women from nine countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC), who had provided blood samples and dietary and other lifestyle information between 1992 and 2000, were included. Results: beta-Cryptoxanthin was most strongly correlated with total fruits (FQ r = 0.52, 24HDR r = 0.39), lycopene with tomato and tomato products (FQ r = 0.38, 24HDR r = 0.25), and alpha-carotene with intake of root vegetables (r = 0.39) and of total carrots (r = 0.38) for FQ only. Based on diet measured by FQ and adjusting for possible confounding by body mass index (BMI), age, gender, smoking status, alcohol intake, and energy intake, the strongest predictors of individual plasma carotenoid levels were fruits (R-partial(2) = 17.2%) for beta-cryptoxanthin, total carrots (R-partial(2) = 13.4%) and root vegetables (R-partial(2) = 13.3%) for alpha-carotene, and tomato products (R-partial(2) = 13.8%) for lycopene. For 24HDR, the highest R-partial(2) was for fruits in relation to beta-cryptoxanthin (7.9%). Conclusions: Intakes of specific fruits and vegetables as measured by food questionnaires are good predictors of certain individual plasma carotenoid levels in our multicentre European study. At individual subject levels, FQ measurements of fruits, root vegetables and carrots, and tomato products are, respectively, good predictors of beta-cryptoxanthin, alpha-carotene, and lycopene in plasma.
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| 18. |
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| 19. |
- Allen, N. E., et al.
(författare)
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Animal foods, protein, calcium and prostate cancer risk: the European Prospective Investigation into Cancer and Nutrition
- 2008
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Ingår i: British Journal of Cancer. - : Springer Science and Business Media LLC. - 1532-1827 .- 0007-0920. ; 98:9, s. 1574-1581
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Tidskriftsartikel (refereegranskat)abstract
- We examined consumption of animal foods, protein and calcium in relation to risk of prostate cancer among 142 251 men in the European Prospective Investigation into Cancer and Nutrition. Associations were examined using Cox regression, stratified by recruitment centre and adjusted for height, weight, education, marital status and energy intake. After an average of 8.7 years of follow-up, there were 2727 incident cases of prostate cancer, of which 1131 were known to be localised and 541 advanced-stage disease. A high intake of dairy protein was associated with an increased risk, with a hazard ratio for the top versus the bottom fifth of intake of 1.22 (95% confidence interval (CI): 1.07-1.41, P-trend = 0.02). After calibration to allow for measurement error, we estimated that a 35-g day(-1) increase in consumption of dairy protein was associated with an increase in the risk of prostate cancer of 32% (95% CI: 1-72%, P-trend = 0.04). Calcium from dairy products was also positively associated with risk, but not calcium from other foods. The results support the hypothesis that a high intake of protein or calcium from dairy products may increase the risk for prostate cancer.
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| 20. |
- Anelli, A., et al.
(författare)
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Measurement and simulation of the neutron response and detection efficiency of a Pb-scintillating fiber calorimeter
- 2008
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Ingår i: IEEE Transactions on Nuclear Science. - 0018-9499 .- 1558-1578. ; 55:3, s. 1409-1412
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Tidskriftsartikel (refereegranskat)abstract
- We have measured the overall detection efficiency to neutrons of a small prototype of the KLOE Pb-scintillating fiber calorimeter in the kinetic energy range [5,175] MeV. using the neutron beam facility of The Svedberg Laboratory, TSL, Uppsala. The measurement of the neutron detection efficiency of a NE110 scintillator provided a reference calibration. At the lowest trigger threshold, the overall calorimeter efficiency ranges from 28% to 33%. This value largely exceeds the estimated similar to 8% expected if the response were proportional only to the scintillator equivalent thickness. A detailed simulation of the calorimeter and of the TSL beamline has been performed with the FLUKA Monte Carlo code. The simulated response of the detector to neutrons is presented together with first data to Monte Carlo comparison. The results show an overall neutron efficiency of about 35%. The reasons for such an efficiency enhancement, in comparison with the typical scintillator-based neutron counters, are explained, opening the road to a novel neutron detector.
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| 21. |
- Anelli, M., et al.
(författare)
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Measurement and simulation of the neutron response and detection efficiency of a Pb-scintillating fiber calorimeter
- 2007
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 581:1-2, s. 368-372
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Tidskriftsartikel (refereegranskat)abstract
- The overall detection efficiency to neutrons of a small prototype of the KLOE Pb-scintillating fiber calorimeter has been measured at the neutron beam facility of The Svedberg Laboratory, TSL, Uppsala, in the kinetic energy range 5-175 MeV. The measurement of the neutron detection efficiency of a NE110 scintillator provided a reference calibration. At the lowest trigger threshold, the overall calorimeter efficiency ranges from 40% to 50%. This value largely exceeds the estimated 8-16% expected if the response were proportional only to the scintillator equivalent thickness. A detailed simulation of the calorimeter and of the TSL beamline has been performed with the FLUKA Monte Carlo code. The simulated response of the detector to neutrons is presented, as well as a first data Monte Carlo comparison. The results show an overall neutron efficiency of about 50%, when no trigger threshold is applied. The reasons of such an efficiency enhancement, in comparison with the typical scintillator-based neutron counters, are explained, opening the road to a novel neutron detector.
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| 22. |
- Anelli, M., et al.
(författare)
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Measurement of the detection efficiency of the KLOE calorimeter for neutrons between 22 and 174 MeV
- 2009
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 598:1, s. 244-247
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Tidskriftsartikel (refereegranskat)abstract
- A prototype of the high-sampling lead-scintillating fiber KLOE calorimeter has been exposed to neutron beams of 21, 46 and 174 MeV, provided by the The Svedberg Laboratory, Uppsala, to test its neutron detection efficiency. The measurement of the neutron detection efficiency of an NE110 scintillator provided a reference calibration. The measured efficiency is larger than what expected considering the scintillator thickness of the KLOE prototype only. This result proves the existence of a contribution from the passive material to neutron detection efficiency, in a high-sampling calorimeter configuration.
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| 23. |
- Daafouz, J., et al.
(författare)
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Switched and piecewise affine systems
- 2009
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Ingår i: Handbook of Hybrid Systems Control. - : Cambridge Press. - 9780511807930 - 9780511807930 ; , s. 87-138
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 24. |
- Manuguerra, M., et al.
(författare)
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Multi-factor dimensionality reduction applied to a large prospective investigation on gene-gene and gene-environment interactions
- 2007
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Ingår i: Carcinogenesis. - : Oxford University Press (OUP). - 0143-3334 .- 1460-2180. ; 28:2, s. 414-422
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Tidskriftsartikel (refereegranskat)abstract
- It is becoming increasingly evident that single-locus effects cannot explain complex multifactorial human diseases like cancer. We applied the multi-factor dimensionality reduction (MDR) method to a large cohort study on gene-environment and gene-gene interactions. The study (case-control nested in the EPIC cohort) was established to investigate molecular changes and genetic susceptibility in relation to air pollution and environmental tobacco smoke (ETS) in non-smokers. We have analyzed 757 controls and 409 cases with bladder cancer (n = 124), lung cancer (n = 116) and myeloid leukemia (n = 169). Thirty-six gene variants (DNA repair and metabolic genes) and three environmental exposure variables (measures of air pollution and ETS at home and at work) were analyzed. Interactions were assessed by prediction error percentage and cross-validation consistency (CVC) frequency. For lung cancer, the best model was given by a significant gene-environment association between the base excision repair (BER) XRCC1-Arg399Gln polymorphism, the double-strand break repair (DSBR) BRCA2-Asn372His polymorphism and the exposure variable 'distance from heavy traffic road', an indirect and robust indicator of air pollution (mean prediction error of 26%, P < 0.001, mean CVC of 6.60, P = 0.02). For bladder cancer, we found a significant 4-loci association between the BER APE1-Asp148Glu polymorphism, the DSBR RAD52-3'-untranslated region (3'-UTR) polymorphism and the metabolic gene polymorphisms COMT-Val158Met and MTHFR-677C > T (mean prediction error of 22%, P < 0.001, mean CVC consistency of 7.40, P < 0.037). For leukemia, a 3-loci model including RAD52-2259C > T, MnSOD-Ala9Val and CYP1A1-Ile462Val had a minimum prediction error of 31% (P < 0.001) and a maximum CVC of 4.40 (P = 0.086). The MDR method seems promising, because it provides a limited number of statistically stable interactions; however, the biological interpretation remains to be understood.
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- Pischon, T., et al.
(författare)
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General and Abdominal Adiposity and Risk of Death in Europe
- 2008
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Ingår i: New England Journal of Medicine. - 0028-4793. ; 359:20, s. 2105-2120
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND Previous studies have relied predominantly on the body-mass index (BMI, the weight in kilograms divided by the square of the height in meters) to assess the association of adiposity with the risk of death, but few have examined whether the distribution of body fat contributes to the prediction of death. METHODS We examined the association of BMI, waist circumference, and waist-to-hip ratio with the risk of death among 359,387 participants from nine countries in the European Prospective Investigation into Cancer and Nutrition (EPIC). We used a Cox regression analysis, with age as the time variable, and stratified the models according to study center and age at recruitment, with further adjustment for educational level, smoking status, alcohol consumption, physical activity, and height. RESULTS During a mean follow-up of 9.7 years, 14,723 participants died. The lowest risks of death related to BMI were observed at a BMI of 25.3 for men and 24.3 for women. After adjustment for BMI, waist circumference and waist-to-hip ratio were strongly associated with the risk of death. Relative risks among men and women in the highest quintile of waist circumference were 2.05 (95% confidence interval [CI], 1.80 to 2.33) and 1.78 (95% CI, 1.56 to 2.04), respectively, and in the highest quintile of waist-to-hip ratio, the relative risks were 1.68 (95% CI, 1.53 to 1.84) and 1.51 (95% CI, 1.37 to 1.66), respectively. BMI remained significantly associated with the risk of death in models that included waist circumference or waist-to-hip ratio (P<0.001). CONCLUSIONS These data suggest that both general adiposity and abdominal adiposity are associated with the risk of death and support the use of waist circumference or waist-tohip ratio in addition to BMI in assessing the risk of death.
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