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1.
  • Abreu, P., et al. (författare)
  • Measurement of the gluon fragmentation function and a comparison of the scaling violation in gluon and quark jets
  • 2000
  • Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 13:4, s. 573-589
  • Tidskriftsartikel (refereegranskat)abstract
    • The fragmentation functions of quarks and gluons are measured in various three-jet topologies in Z decays from the full data set collected with the DELPHI detector at the Z resonance between 1992 and 995. The results at different values of transverse momentum-like scales are compared. A parameterization of the quark and gluon fragmentation functions at a fixed reference scale is given. The quark and gluon fragmentation functions show the predicted pattern of scaling violations. The scaling violation for quark jets as a function of a transverse momentum-like scale is in a good agreement with that observed in lower energy e+e- annihilation experiments. For gluon jets it appears to be significantly stronger. The scale dependences of the gluon and quark fragmentation functions agree with the prediction of the DGLAP evolution equations from which the colour factor ratio CA/CF is measured to be: CA/CF = 2.26 ± 0.09stat. ± 0.06sys. ± 0.12clus.,scale..
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2.
  • Abreu, P., et al. (författare)
  • Study of dimuon production in photon-photon collisions and measurement of QED photon structure functions at LEP
  • 2001
  • Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 19:1, s. 15-28
  • Tidskriftsartikel (refereegranskat)abstract
    • Muon pair production in the process e+e- → e+e- μ+μ- is studied using the data taken at LEP1 (√s ≃ mz) with the DELPHI detector during the years 1992-1995. The corresponding integrated luminosity is 138.5 pb-1. The QED predictions have been tested over the whole Q2 range accessible at LEP1 (from several GeV2/c4 to several hundred GeV2/c4) by comparing experimental distributions with distributions resulting from Monte Carlo simulations using various generators. Selected events are used to extract the leptonic photon structure function Fγ 2. Azimuthal correlations are used to obtain information on additional structure functions, Fγ A and Fγ B, which originate from interference terms of the scattering amplitudes. The measured ratios Fγ A/Fγ 2 and FγB/Fγ 2 are significantly different from zero and consistent with QED predictions.
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3.
  • Abreu, P., et al. (författare)
  • Search for sleptons in e+e- collisions at √s = 183 to 189 GeV
  • 2001
  • Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 19:1, s. 29-42
  • Tidskriftsartikel (refereegranskat)abstract
    • Data taken by the DELPHI experiment at centre-of-mass energies of 183 GeV and 189 GeV with a total integrated luminosity of 212 pb-1 have been used to search for the supersymmetric partners of the electrons, muons, and taus in the context of the Minimal Supersymmetric Standard Model (MSSM). The decay topologies searched for were the direct decay (ℓ̃ → ℓx̃), producing acoplanar lepton pairs plus missing energy, and the cascade decay (ℓ → ℓx̃0 2 → ℓγx̃0 1), producing acoplanar lepton and photon pairs plus missing energy. The observed number of events is in agreement with Standard Model predictions. The 95% CL excluded mass limits for selectrons, smuons and staus are mẽ ≤ 87 GeV/c2, mμ̃ ≤ 80 GeV/c2 and mτ̃ 75 GeV/c2, respectively, for values of μ=-200 GeV/c2 and tanβ=1.5.
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4.
  • Adcox, K, et al. (författare)
  • PHENIX detector overview
  • 2003
  • Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 499:2-3, s. 469-479
  • Tidskriftsartikel (refereegranskat)abstract
    • The PHENIX detector is designed to perform a broad study of A-A, p-A, and p-p collisions to investigate nuclear matter under extreme conditions. A wide variety of probes, sensitive to all timescales, are used to study systematic variations with species and energy as well as to measure the spin structure of the nucleon. Designing for the needs of the heavy-ion and polarized-proton programs has produced a detector with unparalleled capabilities. PHENIX measures electron and muon pairs, photons, and hadrons with excellent energy and momentum resolution. The detector consists of a large number of subsystems that are discussed in other papers in this volume. The overall design parameters of the detector are presented. (C) 2002 Elsevier Science B.V. All rights reserved.
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5.
  • Ahmed, M., et al. (författare)
  • Search for the lepton-family-number nonconserving decay μ +→e +γ
  • 2002
  • Ingår i: Physical Review D. - : American Physical Society. - 1550-7998 .- 1550-2368. ; 65:11
  • Tidskriftsartikel (refereegranskat)abstract
    • The MEGA experiment, which searched for the muon- and electron-number violating decay μ +→e + γ, is described. The spectrometer system, the calibrations, the data taking procedures, the data analysis, and the sensitivity of the experiment are discussed. The most stringent upper limit on the branching ratio, B(μ + →e + γ)<1.2×10 -11 with 90% confidence, is derived from a likelihood analysis.
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6.
  • Alcorn, J, et al. (författare)
  • Basic instrumentation for Hall A at Jefferson Lab
  • 2004
  • Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002. ; 522:3, s. 294-346
  • Tidskriftsartikel (refereegranskat)abstract
    • The instrumentation in Hall A at the Thomas Jefferson National Accelerator Facility was designed to study electro-and photo-induced reactions at very high luminosity and good momentum and angular resolution for at least one of the reaction products. The central components of Hall A are two identical high resolution spectrometers, which allow the vertical drift chambers in the focal plane to provide a momentum resolution of better than 2 x 10(-4). A variety of Cherenkov counters, scintillators and lead-glass calorimeters provide excellent particle identification. The facility has been operated successfully at a luminosity well in excess of 10(38) CM-2 s(-1). The research program is aimed at a variety of subjects, including nucleon structure functions, nucleon form factors and properties of the nuclear medium. (C) 2003 Elsevier B.V. All rights reserved.
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8.
  • Hillier, Ladeana W, et al. (författare)
  • Sequence and comparative analysis of the chicken genome provide unique perspectives on vertebrate evolution
  • 2004
  • Ingår i: Nature. - 0028-0836 .- 1476-4687. ; 432:7018, s. 695-716
  • Tidskriftsartikel (refereegranskat)abstract
    • We present here a draft genome sequence of the red jungle fowl, Gallus gallus. Because the chicken is a modern descendant of the dinosaurs and the first non-mammalian amniote to have its genome sequenced, the draft sequence of its genome--composed of approximately one billion base pairs of sequence and an estimated 20,000-23,000 genes--provides a new perspective on vertebrate genome evolution, while also improving the annotation of mammalian genomes. For example, the evolutionary distance between chicken and human provides high specificity in detecting functional elements, both non-coding and coding. Notably, many conserved non-coding sequences are far from genes and cannot be assigned to defined functional classes. In coding regions the evolutionary dynamics of protein domains and orthologous groups illustrate processes that distinguish the lineages leading to birds and mammals. The distinctive properties of avian microchromosomes, together with the inferred patterns of conserved synteny, provide additional insights into vertebrate chromosome architecture.
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11.
  • Adcox, K, et al. (författare)
  • PHENIX central arm tracking detectors
  • 2003
  • Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 499:2-3, s. 489-507
  • Tidskriftsartikel (refereegranskat)abstract
    • The PHENIX tracking system consists of Drift Chambers (DC), Pad Chambers (PC) and the Time Expansion Chamber (TEC). PC1/DC and PC2/TEC/PC3 form the inner and outer tracking units, respectively. These units link the track segments that transverse the RICH and extend to the EMCal. The DC measures charged particle trajectories in the r-phi direction to determine P-T of the particles and the invariant mass of particle pairs. The PCs perform 3D spatial point measurements for pattern recognition and longitudinal momentum reconstruction and provide spatial resolution of a few mm in both r-phi and z. The TEC tracks particles passing through the region between the RICH and the EMCal. The design and operational parameters of the detectors are presented and running experience during the first year of data taking with PHENIX is discussed. The observed spatial and momentum resolution is given which imposes a limitation on the identification and characterization of charged particles in various momentum ranges. (C) 2002 Published by Elsevier Science B.V.
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13.
  • Rosser, Z H, et al. (författare)
  • Y-chromosomal diversity in Europe is clinal and influenced primarily by geography, rather than by language.
  • 2000
  • Ingår i: American Journal of Human Genetics. - : Elsevier BV. - 0002-9297 .- 1537-6605. ; 67:6, s. 1526-43
  • Tidskriftsartikel (refereegranskat)abstract
    • Clinal patterns of autosomal genetic diversity within Europe have been interpreted in previous studies in terms of a Neolithic demic diffusion model for the spread of agriculture; in contrast, studies using mtDNA have traced many founding lineages to the Paleolithic and have not shown strongly clinal variation. We have used 11 human Y-chromosomal biallelic polymorphisms, defining 10 haplogroups, to analyze a sample of 3,616 Y chromosomes belonging to 47 European and circum-European populations. Patterns of geographic differentiation are highly nonrandom, and, when they are assessed using spatial autocorrelation analysis, they show significant clines for five of six haplogroups analyzed. Clines for two haplogroups, representing 45% of the chromosomes, are continentwide and consistent with the demic diffusion hypothesis. Clines for three other haplogroups each have different foci and are more regionally restricted and are likely to reflect distinct population movements, including one from north of the Black Sea. Principal-components analysis suggests that populations are related primarily on the basis of geography, rather than on the basis of linguistic affinity. This is confirmed in Mantel tests, which show a strong and highly significant partial correlation between genetics and geography but a low, nonsignificant partial correlation between genetics and language. Genetic-barrier analysis also indicates the primacy of geography in the shaping of patterns of variation. These patterns retain a strong signal of expansion from the Near East but also suggest that the demographic history of Europe has been complex and influenced by other major population movements, as well as by linguistic and geographic heterogeneities and the effects of drift.
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14.
  • Adcox, K, et al. (författare)
  • Construction and performance of the PHENIX pad chambers
  • 2003
  • Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 497:2-3, s. 263-293
  • Tidskriftsartikel (refereegranskat)abstract
    • We present the Pad Chamber detector system in the PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. The three station system provides space points along each track in the spectrometer arms at mid-rapidity and covers a total area of 88 m(2). Its main functions are to provide the track coordinate along the beam and to ensure reliable pattern recognition at very high particle multiplicity. A new concept for two dimensional wire chamber readout via its finely segmented cathode was developed. The full readout system, comprising 172 800 electronic channels, is described together with the challenging design of the chambers. The electronics, mounted on the outer chamber face, together with the chamber itself amounts to 1.2% of a radiation length. Results from cosmic ray tests, showing an average efficiency better than 99.5% for all chambers are presented. The experiences from the full scale operation in the first run are reported. (C) 2002 Elsevier Science B.V. All rights reserved.
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15.
  • Lieder, R M, et al. (författare)
  • Gamma-ray tracking arrays
  • 2001
  • Ingår i: PROGRESS IN PARTICLE AND NUCLEAR PHYSICS, VOL 46. ; , s. 399-407
  • Konferensbidrag (refereegranskat)abstract
    • The next generation of 4 pi arrays for high-precision gamma -ray spectroscopy will involve "gamma -ray tracking front-end on digital signal processing techniques, which allows to extract energy, timing and spatial information on the interactions of a gamma -ray in the Ge detector by pulse shape analysis of its signals. Utilizing the information on the positions of the interaction points and the energies released at each point the tracks of the gamma -rays in a Ge shell can be reconstructed in three dimensions.
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16.
  • Lucht, W, et al. (författare)
  • Climatic control of the high-latitude vegetation greening trend and Pinatubo effect
  • 2002
  • Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 1095-9203 .- 0036-8075. ; 296:5573, s. 1687-1689
  • Tidskriftsartikel (refereegranskat)abstract
    • A biogeochemical model of vegetation using observed climate data predicts the high northern latitude greening trend over the past two decades observed by satellites and a marked setback in this trend after the Mount Pinatubo, volcano eruption in 1991. The observed trend toward earlier spring budburst and increased maximum leaf area is produced by the model as a consequence of biogeochemical vegetation responses mainly to changes in temperature. The post-Pinatubo decline in vegetation in 1992-1993 is apparent as the effect of temporary cooling caused by the eruption. High-latitude CO2 uptake during these years is predicted as a consequence of the differential response of heterotrophic respiration and net primary production.
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20.
  • Cho, E, et al. (författare)
  • Dairy foods, calcium, and colorectal cancer : A pooled analysis of 10 cohort studies
  • 2004
  • Ingår i: Journal of the National Cancer Institute. - Harvard Univ, Sch Med, Channing Lab, Boston, MA 02115 USA. Brigham & Womens Hosp, Dept Med, Channing Lab, Boston, MA 02115 USA. Harvard Univ, Sch Publ Hlth, Dept Nutr, Boston, MA 02115 USA. Harvard Univ, Sch Publ Hlth, Dept Epidemiol, Boston, MA 02115 USA. Harvard Univ, Sch Publ Hlth, Dept Biostat, Boston, MA 02115 USA. Loma Linda Univ, Ctr Hlth Res, Sch Med, Loma Linda, CA USA. Maastricht Univ, Dept Epidemiol, Maastricht, Netherlands. Harvard Ctr Canc Prevent, Boston, MA USA. Univ Minnesota, Sch Publ Hlth, Div Epidemiol, Minneapolis, MN 55455 USA. SUNY Buffalo, Dept Social & Prevent Med, Buffalo, NY USA. TNO, Nutr & Food Res Inst, Dept Epidemiol, Zeist, Netherlands. Univ Toronto, Fac Med, Dept Publ Hlth Sci, Toronto, ON, Canada. Natl Publ Hlth Inst, Dept Epidemiol & Hlth Promot, Helsinki, Finland. Fred Hutchinson Canc Res Ctr, Canc Prevent Res Program, Seattle, WA USA. Albert Einstein Coll Med, Dept Epidemiol & Populat Hlth, Bronx, NY 10467 USA. Natl Inst Environm Hlth Sci, Epidemiol Branch, Res Triangle Pk, NC USA. NYU, Dept Obstet Gynecol, Sch Med, New York, NY USA. Natl Inst Environm Med, Div Nutr Epidemiol, Stockholm, Sweden. NYU, Sch Med, Nelson Inst Environm Med & Kaplan Canc Ctr, New York, NY USA. : OXFORD UNIV PRESS INC. - 0027-8874 .- 1460-2105. ; 96:13, s. 1015-1022
  • Tidskriftsartikel (refereegranskat)abstract
    • Background. Studies in animals have suggested that calcium may reduce the risk of colorectal cancer. However, results from epidemiologic studies of intake of calcium or dairy foods and colorectal cancer risk have been inconclusive. Methods: We pooled the primary data from 10 cohort studies in five countries that assessed usual dietary intake by using a validated food frequency questionnaire at baseline. For most studies, follow-up was extended beyond that in the original publication. The studies included 534 536 individuals, among whom 4992 incident cases of colorectal cancer were diagnosed between 6 and 16 years of follow-up. Pooled multivariable relative risks for categories of milk intake and quintiles of calcium intake and 95% confidence intervals (CIs) were calculated. All statistical tests were two-sided. Results: Milk intake was related to a reduced risk of colorectal cancer. Compared with the lowest category of intake (<70 g/day), relative risks of colorectal cancer for increasing categories (70-174, 175-249, and greater than or equal to250 g/day) of milk intake were 0.94 (95% CI = 0.86 to 1.02), 0.88 (95% CI = 0.81 to 0.96), and 0.85 (95% CI = 0.78 to 0.94), respectively (P-trend<.001). Calcium intake was also inversely related to the risk of colorectal cancer. The relative risk for the highest versus the lowest quintile of intake was 0.86 (95% CI = 0.78 to 0.95; P-trend = .02) for dietary calcium and 0.78 (95% CI = 0.69 to 0.88; P-trend<.001) for total calcium (combining dietary and supplemental sources). These results were consistent across studies and sex. The inverse association for milk was limited to cancers of the distal colon (P-trend<.001) and rectum (P-trend = .02). Conclusion: Higher consumption of milk and calcium is associated with a lower risk of colorectal cancer.
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21.
  • Missmer, S A, et al. (författare)
  • Meat and dairy food consumption and breast cancer : a pooled analysis of cohort studies
  • 2002
  • Ingår i: International Journal of Epidemiology. - Harvard Univ, Sch Publ Hlth, Dept Epidemiol, Boston, MA 02115 USA. Brigham & Womens Hosp, Channing Lab, Dept Med, Boston, MA 02115 USA. Harvard Univ, Sch Med, Boston, MA USA. Harvard Univ, Sch Publ Hlth, Dept Nutr, Boston, MA 02115 USA. Harvard Univ, Sch Publ Hlth, Dept Biostat, Boston, MA 02115 USA. Karolinska Inst, Dept Med Epidemiol, Stockholm, Sweden. Loma Linda Univ, Sch Med, Ctr Hlth Res, Loma Linda, CA USA. Maastricht Univ, Dept Epidemiol, Maastricht, Netherlands. SUNY Buffalo, Dept Social & Prevent Med, Buffalo, NY 14260 USA. TNO, Nutr & Food Res Inst, Dept Epidemiol, NL-3700 AJ Zeist, Netherlands. Columbia Univ, Teachers Coll, Dept Hlth & Behav Sci, New York, NY 10027 USA. Deutsch Krebsforschungszentrum, Div Clin Epidemiol, D-6900 Heidelberg, Germany. Fred Hutchinson Canc Res Ctr, Canc Prevent Res Program, Seattle, WA 98104 USA. Albert Einstein Coll Med, Dept Epidemiol & Social Med, New York, NY USA. Harvard Univ, Sch Publ Hlth, Dept Environm Hlth, Boston, MA 02115 USA. NYU, Sch Med, Dept Obstet & Gynecol, New York, NY USA. NYU, Sch Med, Nelson Inst Environm Med, New York, NY USA. Harvard Ctr Canc Prevent, Boston, MA USA. : OXFORD UNIV PRESS. - 0300-5771 .- 1464-3685. ; 31:1, s. 78-85
  • Tidskriftsartikel (refereegranskat)abstract
    • Background More than 20 studies have investigated the relation between meat and dairy food consumption and breast cancer risk with conflicting results. Our objective was to evaluate the risk of breast cancer associated with meat and dairy food consumption and to assess whether non-dietary risk factors modify the relation. Methods We combined the primary data from eight prospective cohort studies from North America and Western Europe with at least 200 incident breast cancer cases, assessment of usual food and nutrient intakes, and a validation study of the dietary assessment instrument. The pooled database included 351 041 women, 7379 of whom were diagnosed with invasive breast cancer during up to 15 years of follow-up. Results We found no significant association between intakes of total meat, red meat, white meat, total dairy fluids, or total dairy solids and breast cancer risk. Categorical analyses suggested a J-shaped association for egg consumption where, compared to women who did not eat eggs, breast cancer risk was slightly decreased among women who consumed <2 eggs per week but slightly increased among women who consumed greater than or equal to1 egg per day. Conclusions We found no significant associations between intake of meat or dairy products and risk of breast cancer. An inconsistent relation between egg consumption and risk of breast cancer merits further investigation.
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22.
  • Smith, K.A., et al. (författare)
  • Oxidation of atmospheric methane in Northern European soils, comparison with other ecosystems, and uncertainties in the global terrestrial sink
  • 2000
  • Ingår i: Global Change Biology. - : Wiley. - 1354-1013 .- 1365-2486. ; 6:7, s. 791-803
  • Tidskriftsartikel (refereegranskat)abstract
    • This paper reports the range and statistical distribution of oxidation rates of atmospheric CH4 in soils found in Northern Europe in an international study, and compares them with published data for various other ecosystems. It reassesses the size, and the uncertainty in, the global terrestrial CH4 sink, and examines the effect of land-use change and other factors on the oxidation rate. Only soils with a very high water table were sources of CH4, all others were sinks. Oxidation rates varied from 1 to nearly 200 µg CH4 m-2 h-1, annual rates for sites measured for =1 y were 0.1-9.1 kg CH4 ha-1 y-1, with a log-normal distribution (log-mean ~ 1.6 kg CH4 ha-1 y-1). Conversion of natural soils to agriculture reduced oxidation rates by two-thirds - closely similar to results reported for other regions. N inputs also decreased oxidation rates. Full recovery of rates after these disturbances takes > 100 y. Soil bulk density, water content and gas diffusivity had major impacts on oxidation rates. Trends were similar to those derived from other published work. Increasing acidity reduced oxidation, partially but not wholly explained by poor diffusion through litter layers which did not themselves contribute to the oxidation. The effect of temperature was small, attributed to substrate limitation and low atmospheric concentration. Analysis of all available data for CH4 oxidation rates in situ showed similar log-normal distributions to those obtained for our results, with generally little difference between different natural ecosystems, or between short-and longer-term studies. The overall global terrestrial sink was estimated at 29 Tg CH4 y-1, close to the current IPCC assessment, but with a much wider uncertainty range (7 to > 100 Tg CH4 y-1). Little or no information is available for many major ecosystems, these should receive high priority in future research.
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23.
  • Smith-Warner, S A, et al. (författare)
  • Intake of fruits and vegetables and risk of breast cancer - A pooled analysis of cohort studies
  • 2001
  • Ingår i: Journal of the American Medical Association (JAMA). - Harvard Univ, Sch Publ Hlth, Dept Nutr, Ctr Canc Prevent, Boston, MA 02115 USA. Harvard Univ, Sch Publ Hlth, Dept Epidemiol, Ctr Canc Prevent, Boston, MA 02115 USA. Harvard Univ, Sch Publ Hlth, Dept Biostat, Ctr Canc Prevent, Boston, MA 02115 USA. Harvard Univ, Sch Publ Hlth, Dept Environm Hlth, Ctr Canc Prevent, Boston, MA 02115 USA. Brigham & Womens Hosp, Dept Med, Channing Lab, Boston, MA USA. Harvard Univ, Sch Med, Boston, MA 02115 USA. Karolinska Inst, Dept Med Epidemiol, Stockholm, Sweden. Loma Linda Univ, Sch Med, Ctr Hlth Res, Loma Linda, CA USA. Maastricht Univ, Dept Epidemiol, Maastricht, Netherlands. Univ Minnesota, Sch Publ Hlth, Div Epidemiol, Minneapolis, MN 55455 USA. SUNY Buffalo, Dept Social & Prevent Med, Buffalo, NY 14260 USA. TNO, Nutr & Food Res Inst, NL-3700 AJ Zeist, Netherlands. Deutsch Krebsforschungszentrum, Div Clin Epidemiol, D-6900 Heidelberg, Germany. Fred Hutchinson Canc Res Ctr, Canc Prevent Res Program, Seattle, WA 98104 USA. Albert Einstein Coll Med, Dept Epidemiol & Social Med, Bronx, NY 10467 USA. NYU, Sch Med, Dept Obstet & Gynecol, New York, NY USA. NYU, Sch Med, Nelson Inst Environm Med, New York, NY USA. NYU, Sch Med, Kaplan Canc Ctr, New York, NY USA. : AMER MEDICAL ASSOC. - 0098-7484 .- 1538-3598. ; 285:6, s. 769-776
  • Forskningsöversikt (refereegranskat)abstract
    • Context Some epidemiologic studies suggest that elevated fruit and vegetable consumption is associated with a reduced risk of breast cancer. However, most have been case-control studies in which recall and selection bias may influence the results. Additionally, publication bias may have influenced the literature on associations for specific fruit and vegetable subgroups. Objective To examine the association between breast cancer and total and specific fruit and vegetable group intakes using standardized exposure definitions. Data Sources/Study Selection Eight prospective studies that had at least 200 incident breast cancer cases, assessed usual dietary intake, and completed a validation study of the diet assessment method or a closely related instrument were included in these analyses. Data Extraction Using the primary data from each of the studies, we calculated study-specific relative risks (RRs) that were combined using a random-effects model. Data Synthesis The studies included 7377 incident invasive breast cancer cases occurring among 351825 women whose diet was analyzed at baseline. For comparisons of the highest vs lowest quartiles of intake, weak, nonsignificant associations were observed for total fruits (pooled multivariate RR, 0.93; 95% confidence interval [CI], 0.86-1.00; P for trend =.08), total vegetables (RR, 0.96; 95% CI, 0.89-1.04; P for trend=.54), and total fruits and vegetables (RR, 0.93; 95% CI, 0.86-1.00; P for trend=.12). No additional benefit was apparent in comparisons of the highest and lowest deciles of intake. No associations were observed for green leafy vegetables, 8 botanical groups, and 17 specific fruits and vegetables. Conclusion These results suggest that fruit and vegetable consumption during adulthood is not significantly associated with reduced breast cancer risk.
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24.
  • Smith-Warner, S A, et al. (författare)
  • Types of dietary fat and breast cancer : a pooled analysis of cohort studies
  • 2001
  • Ingår i: International Journal of Cancer. - 0020-7136 .- 1097-0215. ; 92:5, s. 767-74
  • Tidskriftsartikel (refereegranskat)abstract
    • Recently, there has been interest in whether intakes of specific types of fat are associated with breast cancer risk independently of other types of fat, but results have been inconsistent. We identified 8 prospective studies that met predefined criteria and analyzed their primary data using a standardized approach. Holding total energy intake constant, we calculated relative risks for increments of 5% of energy for each type of fat compared with an equivalent amount of energy from carbohydrates or from other types of fat. We combined study-specific relative risks using a random effects model. In the pooled database, 7,329 incident invasive breast cancer cases occurred among 351,821 women. The pooled relative risks (95% confidence intervals [CI]) for an increment of 5% of energy were 1.09 (1.00-1.19) for saturated, 0.93 (0.84-1.03) for monounsaturated and 1.05 (0.96-1.16) for polyunsaturated fat compared with equivalent energy intake from carbohydrates. For a 5% of energy increment, the relative risks were 1.18 (95% CI 0.99-1.42) for substituting saturated for monounsaturated fat, 0.98 (95% CI 0.85-1.12) for substituting saturated for polyunsaturated fat and 0.87 (95% CI 0.73-1.02) for substituting monounsaturated for polyunsaturated fat. No associations were observed for animal or vegetable fat intakes. These associations were not modified by menopausal status. These data are suggestive of only a weak positive association with substitution of saturated fat for carbohydrate consumption; none of the other types of fat examined was significantly associated with breast cancer risk relative to an equivalent reduction in carbohydrate consumption.
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25.
  • Wells, R S, et al. (författare)
  • The Eurasian heartland : a continental perspective on Y-chromosome diversity.
  • 2001
  • Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 98:18, s. 10244-9
  • Tidskriftsartikel (refereegranskat)abstract
    • The nonrecombining portion of the human Y chromosome has proven to be a valuable tool for the study of population history. The maintenance of extended haplotypes characteristic of particular geographic regions, despite extensive admixture, allows complex demographic events to be deconstructed. In this study we report the frequencies of 23 Y-chromosome biallelic polymorphism haplotypes in 1,935 men from 49 Eurasian populations, with a particular focus on Central Asia. These haplotypes reveal traces of historical migrations, and provide an insight into the earliest patterns of settlement of anatomically modern humans on the Eurasian continent. Central Asia is revealed to be an important reservoir of genetic diversity, and the source of at least three major waves of migration leading into Europe, the Americas, and India. The genetic results are interpreted in the context of Eurasian linguistic patterns.
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26.
  • Wilson, W G, et al. (författare)
  • Biodiversity and species interactions: extending Lotka-Volterra community theory
  • 2003
  • Ingår i: Ecology Letters. - : Wiley. - 1461-023X .- 1461-0248. ; 6:10, s. 944-952
  • Tidskriftsartikel (refereegranskat)abstract
    • A new analysis of the nearly century-old Lotka-Volterra theory allows us to link species interactions to biodiversity patterns, including: species abundance distributions, estimates of total community size, patterns of community invasibility, and predicted responses to disturbance. Based on a few restrictive assumptions about species interactions, our calculations require only that the community is sufficiently large to allow a mean-field approximation. We develop this analysis to show how an initial assemblage of species with varying interaction strengths is predicted to sort out into the final community based on the species' predicted target densities. The sorting process yields predictions of covarying patterns of species abundance, community size, and species interaction strengths. These predictions can be tested using enrichment experiments, examination of latitudinal and productivity gradients, and features of community assembly.
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27.
  • Astuto, Lisa M., et al. (författare)
  • Genetic heterogeneity of Usher syndrome : analysis of 151 families with Usher type 1
  • 2000
  • Ingår i: American Journal of Human Genetics. - : Elsevier BV. - 0002-9297 .- 1537-6605. ; 67:6, s. 1569-1574
  • Tidskriftsartikel (refereegranskat)abstract
    • Usher syndrome type I is an autosomal recessive disorder marked by hearing loss, vestibular areflexia, and retinitis pigmentosa. Six Usher I genetic subtypes at loci USH1A-USH1F have been reported. The MYO7A gene is responsible for USH1B, the most common subtype. In our analysis, 151 families with Usher I were screened by linkage and mutation analysis. MYO7A mutations were identified in 64 families with Usher I. Of the remaining 87 families, who were negative for MYO7A mutations, 54 were informative for linkage analysis and were screened with the remaining USH1 loci markers. Results of linkage and heterogeneity analyses showed no evidence of Usher types Ia or Ie. However, one maximum LOD score was observed lying within the USH1D region. Two lesser peak LOD scores were observed outside and between the putative regions for USH1D and USH1F, on chromosome 10. A HOMOG chi(2)((1)) plot shows evidence of heterogeneity across the USH1D, USH1F, and intervening regions. These results provide conclusive evidence that the second-most-common subtype of Usher I is due to genes on chromosome 10, and they confirm the existence of one Usher I gene in the previously defined USH1D region, as well as providing evidence for a second, and possibly a third, gene in the 10p/q region.
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28.
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29.
  • Duffy, S.W., et al. (författare)
  • The Swedish two-county trial of mammographic screening : Cluster randomisation and end point evaluation
  • 2003
  • Ingår i: Annals of Oncology. - : Elsevier BV. - 0923-7534 .- 1569-8041. ; 14:8, s. 1196-1198
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: The Swedish Two-County Trial has been criticised on the grounds of the cluster randomisation and alleged bias in classification of cause of death. Patients and methods: In the Two-County Trial, 77080 women were randomised to regular invitation to screening (active study population, ASP) and 55985 to no invitation (passive study population, PSP), in 45 geographical clusters. After ~7 years, the PSP was invited to screening and the trial closed. We analysed data using hierarchical statistical models to take account of cluster randomisation, and performed a conservative analysis assuming a systematic difference between ASP and PSP in baseline breast cancer mortality in one of the counties. We also analysed deaths from causes other than breast cancer and from all causes among breast cancer cases diagnosed in the ASP and PSP. Results: Taking account of the cluster randomisation there was a significant 30% reduction in breast cancer mortality in the ASP. Conservatively, assuming a systematic difference between ASP and PSP clusters in baseline breast cancer mortality, there was a significant 27% reduction in mortality in the ASP. Ignoring classification of cause of death, there was a significant 13% reduction in all-cause mortality in breast cancer cases in the ASP. Conclusions: Breast cancer mortality is a valid end point and mammographic screening does indeed reduce mortality from breast cancer. The criticisms of the Swedish Two-County Trial are unfounded.
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30.
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31.
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32.
  • Simpson, J., et al. (författare)
  • Discrete line γ-ray spectroscopy in the (50-60)ℏ spin domain of 161,162Er
  • 2000
  • Ingår i: Physical Review C - Nuclear Physics. - 0556-2813. ; 62:2, s. 243211-243218
  • Tidskriftsartikel (refereegranskat)abstract
    • Very high spin states (I=50-60ℏ) have been observed in the transitional nuclei 161Er and 162Er using the Euroball γ-ray spectrometer. In 161Er, three bands are observed well above spin 50ℏ. In the positive parity, positive signature (+, + 1/2) band a discontinuity in the regular rotational behavior occurs at 109/2+ and a splitting into two branches occurs at 97/2- in the negative parity, positive signature (-, + 1/2) band. The ( -, - 1/2) band continues in a regular fashion to 115/2-, tentatively (119/2-). In 162Er the positive parity, even spin (+, 0) yrast band is observed to continue smoothly up to 58+ (60+) and the negative parity, even spin (-,0) and odd spin (-,1) bands are extended from 30- to 34- and from 31- to 47- (49-), respectively. The high spin experimental spectra are compared with both a simple model involving the occupation of specific single neutron states in the absence of neutron pair correlations and with more detailed cranked Nilsson-Strutinsky calculations in which both proton and neutron pairing correlations are neglected. The very high spin domain is found to comprise a series of unpaired rotational bands. Unpaired band crossings between bands with different neutron and proton configurations are identified in 161Er. There is no evidence for aligned oblate or terminating states being close to the yrast line in 161,162Er up to spin ≈60ℏ in contrast to the lighter Er isotopes.
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33.
  • Smith, B. K., et al. (författare)
  • Sliver Stringers and Junior Journalists : Active information producers
  • 2000
  • Ingår i: IBM Systems Journal. - : IBM. - 0018-8670. ; 39:04-mar, s. 730-748
  • Tidskriftsartikel (refereegranskat)abstract
    • Two projects, Silver Stringers and Junior Journalists, are examples of a shift in the role of the news consumer - community members are actively engaged in publishing pursuits previously confined to the traditional media. Their activities range from news gathering and dissemination to asking questions and debating issues of importance, whether local, international, or topical in scope. This paper describes the evolution of these projects, the experiences of the participants, the technologies developed and employed, and the epistemological impact.
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34.
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35.
  • Tabar, L., et al. (författare)
  • All-cause mortality among breast cancer patients in a screening trial : Support for breast cancer mortality as an end point
  • 2002
  • Ingår i: Journal of Medical Screening. - : SAGE Publications. - 0969-1413 .- 1475-5793. ; 9:4, s. 159-162
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: It has recently been suggested that all-cause mortality is a more appropriate end point than disease specific mortality in cancer screening trials, and that disease specific mortality is biased in favour of screening. This suggestion is based partly on supposed inconsistencies between all-cause mortality results and disease specific results in cancer screening trials, and alleged increases in deaths from causes other than breast cancer among breast cancer cases diagnosed among women invited to screening. Methods: We used data from the Swedish Two-County Trial of mammographic screening for breast cancer, in which 77 080 women were randomised to an invitation to screening and 55 985 to no invitation. We estimated relative risks (RRs) (invited v control) of death from breast cancer, death from other causes within the breast cancer cases, and death from all causes within the breast cancer cases. RRs were adjusted for age and took account of the longer follow up of breast cancer cases in the invited group due to lead time. Results: There was a significant 31% reduction in breast cancer mortality in the invited group (RR 0.69, 95% confidence interval (Cl) 0.58-0.80, p
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36.
  • Tabar, L., et al. (författare)
  • Number needed to screen : Lives saved over 20 years of follow-up in mammographic screening
  • 2004
  • Ingår i: Journal of Medical Screening. - : SAGE Publications. - 0969-1413 .- 1475-5793. ; 11:3, s. 126-129
  • Tidskriftsartikel (refereegranskat)abstract
    • Objective: To estimate the number needed to screen with mammography to save one life, based on a stated amount of screening activity and long-term follow-up for breast cancer death. Setting: A randomised controlled trial of mammographic screening for breast cancer, with 77,080 women invited to screening and 55,985 not invited. The invited group was offered screening for seven years. Follow-up continued for a total of just over 20 years. Methods: Number needed to screen for seven years to save one life over 20 years was calculated by dividing the number screened (not the number invited) by the total number of lives saved. Similarly, we calculated the number of mammographic examinations required to save one life. Results: We estimate that the number of women needed to screen for seven years to save one life over 20 years is 465 (95% CI 324-819). The number of mammographic examinations needed to save one life was 1499 (95% CI 1046-2642). Conclusions: The number needed to screen to save one life is smaller than has been reported in the past. Mammographic screening is effective in absolute terms as well as relative. Long-term follow-up allowed us to estimate the absolute benefit with greater accuracy.
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37.
  • van den Brandt, P A, et al. (författare)
  • Pooled analysis of prospective cohort studies on height, weight, and breast cancer risk
  • 2000
  • Ingår i: American Journal of Epidemiology. - Maastricht Univ, Dept Epidemiol, NL-6200 MD Maastricht, Netherlands. Harvard Univ, Sch Publ Hlth, Dept Epidemiol, Boston, MA 02115 USA. Harvard Univ, Sch Publ Hlth, Dept Biostat, Boston, MA 02115 USA. Brigham & Womens Hosp, Dept Med, Channing Lab, Boston, MA USA. Harvard Univ, Sch Med, Boston, MA USA. Karolinska Inst, Dept Med Epidemiol, Stockholm, Sweden. Loma Linda Univ, Sch Med, Ctr Hlth Res, Loma Linda, CA USA. Univ Minnesota, Sch Publ Hlth, Div Epidemiol, Minneapolis, MN 55455 USA. TNO, Nutr & Food Res Inst, Dept Epidemiol, NL-3700 AJ Zeist, Netherlands. SUNY Buffalo, Dept Social & Prevent Med, Buffalo, NY 14260 USA. Univ Arizona, Arizona Canc Ctr, Tucson, AZ USA. Univ Toronto, Fac Med, Dept Publ Hlth Sci, Toronto, ON, Canada. Harvard Univ, Sch Publ Hlth, Dept Nutr, Boston, MA 02115 USA. Harvard Univ, Sch Publ Hlth, Dept Environm Hlth, Boston, MA 02115 USA. Harvard Univ, Ctr Canc Prevent, Boston, MA 02115 USA. : OXFORD UNIV PRESS INC. - 0002-9262 .- 1476-6256. ; 152:6, s. 514-527
  • Tidskriftsartikel (refereegranskat)abstract
    • The association between anthropometric indices and the risk of breast cancer was analyzed using pooled data from seven prospective cohort studies. Together, these cohorts comprise 337,819 women and 4,385 incident invasive breast cancer cases. in multivariate analyses controlling for reproductive, dietary, and other risk factors, the pooled relative risk (RR) of breast cancer per height increment of 5 cm was 1.02 (95% confidence interval (CI): 0.96, 1.10) in premenopausal women and 1.07 (95% CI: 1.03, 1.12) in postmenopausal women. Body mass index (BMI) showed significant inverse and positive associations with breast cancer among pre- and postmenopausal women, respectively; these associations were nonlinear. Compared with premenopausal women with a BMI of less than 21 kg/m(2), women with a BMI exceeding 31 kg/m(2) had an RR of 0.54 (95% CI: 0.34, 0.85). In postmenopausal women, the RRs did not increase further when BMI exceeded 28 kg/m(2); the RR for these women was 1.26 (95% CI: 1.09, 1.46). The authors found little evidence for interaction with other breast cancer risk factors. Their data indicate that height is an independent risk factor for postmenopausal breast cancer; in premenopausal women, this relation is less clear. The association between BMI and breast cancer Varies by menopausal status. Weight control may reduce the risk among postmenopausal women.
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