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1.	Ahrens, J., et al. (författare) Observation of high energy atmospheric neutrinos with the Antarctic muon and neutrino detector array 2002 Ingår i: Physical Review D. - : American Physical Society. - 1550-7998 .- 1550-2368. ; 66:1, s. 120051-1200520 Tidskriftsartikel (refereegranskat)abstract The Antarctic muon and neutrino detector array (AMANDA) began collecting data with ten strings in 1997. Results from the first year of operation are presented. Neutrinos coming through the Earth from the Northern Hemisphere are identified by secondary muons moving upward through the array. Cosmic rays in the atmosphere generate a background of downward moving muons, which are about 106 times more abundant than the upward moving muons. Over 130 days of exposure, we observed a total of about 300 neutrino events. In the same period, a background of 1.05 × 109 cosmic ray muon events was recorded. The observed neutrino flux is consistent with atmospheric neutrino predictions. Monte Carlo simulations indicate that 90% of these events lie in the energy range 66 GeV to 3.4 TeV. The observation of atmospheric neutrinos consistent with expectations establishes AMANDA-B10 as a working neutrino telescope.
2.	Abt, I, et al. (författare) Inclusive V-0 production cross sections from 920 GeV fixed target proton-nucleus collisions 2003 Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 29:2, s. 181-190 Tidskriftsartikel (refereegranskat)abstract Inclusive differential cross sections dsigma(pA)/dx(F) and dsigma(pA)/dp(t)(2) for the production of K-S(0), Lambda, and (&ULambda;) over bar particles are measured at HERA in proton-induced reactions on C, Al, Ti, and W targets. The incident beam energy is 920 GeV, corresponding to roots = 41.6 GeV in the proton-nucleon system. The ratios of differential cross sections dsigma(pA)(K-S(0))/dsigma(pA)(Lambda) and dsigma(pA)((&ULambda;) over bar)/dsigma(pA) (Lambda) are measured to be 6.2 +/- 0.5 and 0.66 +/- 0.07, respectively, for x(F) approximate to -0.06. No significant dependence upon the target material is observed. Within errors, the slopes of the transverse momentum distributions da,Ald t also show no significant dependence upon the target material. The dependence of the extrapolated total cross sections sigma(pA) on the atomic mass A of the target material is discussed, and the deduced cross sections per nucleon sigma(pN) are compared with results obtained at other energies.
3.	Abt, I, et al. (författare) Measurement of the b(b)over-bar production cross section in 920 GeV fixed-target proton-nucleus collisions 2003 Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 26:3, s. 345-355 Tidskriftsartikel (refereegranskat)abstract Using the HERA-B detector, the b (b) over bar production cross section has been measured in 920 GeV proton collisions on carbon and titanium targets. The b (b) over bar production was tagged via inclusive bottom quark decays into J/psi by exploiting the longitudinal separation of J/psi --> l(+)l(-) decay vertices from the primary proton-nucleus interaction. Both e(+)e(-) and mu(+)mu(-) channels have been reconstructed and the combined analysis yields the cross section sigma(b (b) over bar) = 32(-12)(+14)(stat) (+6)(-7)(sys) nb/nucleon.
4.	Andres, E., et al. (författare) Selected recent results from AMANDA 2001 Ingår i: ICHEP 2000. Proceedings of the 30th International Conference on High Energy Physics. - : World Scientific. ; , s. 965-968 Konferensbidrag (refereegranskat)abstract We present a selection of results based on data taken in 1997 with the 302-PMT Antarctic Muon and Neutrino Detector Array-B10 ("AMANDA-B10") array. Atmospheric neutrinos created in the northern hemisphere are observed indirectly through their charged current interactions which produce relativistic, Cherenkov-light-emitting upgoing muons in the South Pole ice cap. The reconstructed angular distribution of these events is in good agreement with expectation and demonstrates the viability of this ice-based device as a neutrino telescope. Studies of nearly vertical upgoing muons limit the available parameter space for WIMP dark matter under the assumption that WIMPS are trapped in the earth's gravitational potential well and annihilate with one another near the earth's center.
5.	Andrés, E., et al. (författare) Observation of high-energy neutrinos using Čerenkov detectors embedded deep in Antarctic ice 2001 Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 410:6827, s. 441-443 Tidskriftsartikel (refereegranskat)abstract Neutrinos are elementary particles that carry no electric charge and have little mass. As they interact only weakly with other particles, they can penetrate enormous amounts of matter, and therefore have the potential to directly convey astrophysical information from the edge of the Universe and from deep inside the most cataclysmic high-energy regions. The neutrino's great penetrating power, however, also makes this particle difficult to detect. Underground detectors have observed low-energy neutrinos from the Sun and a nearby supernova2, as well as neutrinos generated in the Earth's atmosphere. But the very low fluxes of high-energy neutrinos from cosmic sources can be observed only by much larger, expandable detectors in, for example, deep water3,4 or ice5. Here we report the detection of upwardly propagating atmospheric neutrinos by the ice-based Antarctic muon and neutrino detector array (AMANDA). These results establish a technology with which to build a kilometre-scale neutrino observatory necessary for astrophysical observations1.
6.	Andrés, E., et al. (författare) Recent results from AMANDA 2001 Ingår i: International Journal of Modern Physics A. - 0217-751X .- 1793-656X. ; 16:1C, s. 1013-1015 Tidskriftsartikel (refereegranskat)abstract We present results based on data taken in 1997 with the 302-PMT Antarctic Muon and Neutrino Detector Array-B10 ("AMANDA-B10") array. Atmospheric neutrinos created in the northern hemisphere are observed indirectly through their charged current interactions which produce relativistic, Cherenkov-light-emitting upgoing muons in the South Pole ice cap. The reconstructed angular distribution of these events is in good agreement with expectation and demonstrates the viability of this ice-based device as a neutrino telescope.
7.	Karle, A., et al. (författare) Observation of high energy atmospheric neutrinos with AMANDA 2000 Ingår i: AIP Conference Proceedings. - : American Institute of Physics (AIP). ; , s. 823-827 Konferensbidrag (refereegranskat)abstract In 1997 the Antarctic Muon and Neutrino Detector Array (AMANDA) started operating with 10 strings. In an analysis of data taken during the first year of operation 188 atmospheric neutrino candidates were found. Their zenith angle distribution agrees with expectations based on Monte Carlo simulations. A preliminary upper limit is given on a diffuse flux of high energy neutrinos of astrophysical origin.
8.	Wiebusch, C., et al. (författare) Results from AMANDA 2002 Ingår i: Modern Physics Letters A. - : Institution of Electrical Engineers (IEE). - 0217-7323 .- 1793-6632. ; 17:31, s. 2019-2037 Tidskriftsartikel (refereegranskat)abstract The Antarctic Muon and Neutrino Detector Array (AMANDA) is a high-energy neutrino telescope operating at the geographic South Pole. It is a lattice of photomultiplier tubes buried deep in the polar ice. The primary goal of this detector is to discover astrophysical sources of high energy neutrinos. We describe the detector methods of operation and present results from the AMANDA-B10 prototype. We demonstrate the improved sensitivity of the current AMANDA-II detector. We conclude with an outlook to the envisioned sensitivity of the future IceCube detector.
9.	Ahrens, J., et al. (författare) Search for supernova neutrino bursts with the AMANDA detector 2001 Ingår i: Astroparticle physics. - : Elsevier. - 0927-6505 .- 1873-2852. ; 16:4, s. 345-359 Tidskriftsartikel (refereegranskat)abstract The core collapse of a massive star in the Milky Way will produce a neutrino burst, intense enough to be detected by existing underground detectors. The AMANDA neutrino telescope located deep in the South Pole ice can detect MeV neutrinos by a collective rate increase in all photo-multipliers on top of dark noise. The main source of light comes from positrons produced in the CC reaction of anti-electron neutrinos on free protons ve + p → e+ + n. This paper describes the first supernova search performed on the full sets of data taken during 1997 and 1998 (215 days of live time) with 302 of the detector's optical modules. No candidate events resulted from this search. The performance of the detector is calculated, yielding a 70% coverage of the galaxy with one background fake per year with 90% efficiency for the detector configuration under study. An upper limit at the 90% c.l. on the rate of stellar collapses in the Milky Way is derived, yielding 4.3 events per year. A trigger algorithm is presented and its performance estimated. Possible improvements of the detector hardware are reviewed.
10.	Ahrens, J., et al. (författare) Results from the Antarctic muon and nuetrino detector array 2003 Ingår i: Nuclear physics B, Proceedings supplements. - : Elsevier. - 0920-5632 .- 1873-3832. ; 118, s. 371-379 Tidskriftsartikel (refereegranskat)abstract We show new results from both the older and newer incarnations of AMANDA (AMANDA-B10 and AMANDA-II, respectively). These results demonstrate that AMANDA is a functioning, multipurpose detector with significant physics and astrophysics reach. They include a new higher-statistics measurement of the atmospheric muon neutrino flux and preliminary results from searches for a variety of sources of ultrahigh energy neutrinos: generic point sources, gamma-ray bursters and diffuse sources producing muons in the detector, and diffuse sources producing electromagnetic or hadronic showers in or near the detector.
11.	Kowalski, Marek, et al. (författare) Physics results from the AMANDA neutrino detector 2001 Ingår i: Proceedings of Science. - 1824-8039. ; HEP2001 Tidskriftsartikel (refereegranskat)abstract In the winter season of 2000, the AMANDA (Antarctic Muon And NeutrinoDetector Array) detector was completed to its nal state. We report on major physicsresults obtained from the AMANDA-B10 detector, as well as initial results of the fullAMANDA-II detector.
12.	Ahrens, J., et al. (författare) Initial results from AMANDA 2001 Ingår i: 21st Rencontres de Moriond Workshop on Very High-Energy Phenomena in the Universe. Konferensbidrag (refereegranskat)
13.	Ahrens, J., et al. (författare) Results from AMANDA 2001 Ingår i: Proceedings, 9th International Workshop, Venice, Italy, March 6-9, 2001. Vol. 1, 2. ; , s. 569-580 Konferensbidrag (refereegranskat)
14.	Ahrens, J., et al. (författare) Search for Extraterrestrial Point Sources of Neutrinos with AMANDA-II 2004 Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 92:7, s. 711021-711025 Tidskriftsartikel (refereegranskat)abstract The results of a search for point sources of high energy neutrinos in the northern hemisphere were presented using AMANDA-II data collected in the year 2000. The results included the flux limits on several active-galactic-nuclei blazars, microquasars, magnetars, and other candidate neutrino sources. A search for excesses above a random background of cosmic ray induced atmospheric neutrinos and misreconstructed downgoing cosmic-rays muons, which revealed no statistically significant neutrino point sources was also presented. It was shown that AMANDA-II had achieved the sensitivity required to probe known TeV γ-ray sources such as the blazar Markarian 501 in its 1997 flaring state at a level where neutrino and γ-ray fluxes were equal.
15.	Ahrens, J., et al. (författare) Search for neutrino-induced cascades with the AMANDA detector 2003 Ingår i: Physical Review D. - : American Physical Society (APS). - 1550-7998 .- 1550-2368. ; 67:1, s. 012003- Tidskriftsartikel (refereegranskat)abstract We report on a search for electromagnetic and/or hadronic showers (cascades) induced by a diffuse flux of neutrinos with energies between 5 TeV and 300 TeV from extraterrestrial sources. Cascades may be produced by matter interactions of all flavors of neutrinos, and contained cascades have better energy resolution and afford better background rejection than throughgoing νμ-induced muons. Data taken in 1997 with the AMANDA detector were searched for events with a high-energy cascadelike signature. The observed events are consistent with expected backgrounds from atmospheric neutrinos and catastrophic energy losses from atmospheric muons. Effective volumes for all flavors of neutrinos, which allow the calculation of limits for any neutrino flux model, are presented. The limit on cascades from a diffuse flux of νe+ νμ + ντ+ ν̄e + ν̄μ+ ν̄τ is E2(dΦ/dE)<9.8×10-6 GeV cm-2 s-1 sr-1, assuming a neutrino flavor flux ratio of 1:1:1 at the detector. The limit on cascades from a diffuse flux of νe+ν̄e is E2(dΦ/dE)<6. 5×10-6 GeV cm-2 s-1 sr-1, independent of the assumed neutrino flavor flux ratio. © 2003 The American Physical Society.
16.	Bai, X., et al. (författare) Status of the Neutrino Telescope AMANDA : Monopoles and WIMPS 2001 Ingår i: Dark Matter in Astro- and Particle Physics. - Berlin, Heidelberg : Springer. - 9783642626081 ; , s. 699-706 Konferensbidrag (refereegranskat)abstract The neutrino telescope AMANDA has been set up at the geographical South Pole as first step to a neutrino telescope of the scale of one cubic kilometer, which is the canonical size for a detector sensitive to neutrinos from Active Galactic Nuclei (AGN), Gamma Ray Bursts (GRB) and Topological Defects (TD). The location and depth in which the detector is installed is given by the requirement to detect neutrinos by the Cherenkov light produced by their reaction products and to keep the background due to atmospheric muons as small as possible. However, a detector optimized for this purpose is also capable to detect the bright Cherenkov light from relativistic Monopoles and neutrino signals from regions with high gravitational potential, where WIMPS are accumulated and possibly annihilate. Both hypothetical particles might contribute to the amount of dark matter. Therefore here a report about the status of the experiment (autumn 2000) and about the status of the search for these particles with the AMANDA B10 sub-detector is given.
17.	Imanishi, T., et al. (författare) Integrative annotation of 21,037 human genes validated by full-length cDNA clones 2004 Ingår i: PLoS biology. - : Public Library of Science (PLoS). - 1544-9173 .- 1545-7885. ; 2:6, s. 856-875 Tidskriftsartikel (refereegranskat)abstract The human genome sequence defines our inherent biological potential; the realization of the biology encoded therein requires knowledge of the function of each gene. Currently, our knowledge in this area is still limited. Several lines of investigation have been used to elucidate the structure and function of the genes in the human genome. Even so, gene prediction remains a difficult task, as the varieties of transcripts of a gene may vary to a great extent. We thus performed an exhaustive integrative characterization of 41,118 full-length cDNAs that capture the gene transcripts as complete functional cassettes, providing an unequivocal report of structural and functional diversity at the gene level. Our international collaboration has validated 21,037 human gene candidates by analysis of high-quality full-length cDNA clones through curation using unified criteria. This led to the identification of 5,155 new gene candidates. It also manifested the most reliable way to control the quality of the cDNA clones. We have developed a human gene database, called the H-Invitational Database (H-InvDB; http://www.h-invitational.jp/). It provides the following: integrative annotation of human genes, description of gene structures, details of novel alternative splicing isoforms, non-protein-coding RNAs, functional domains, subcellular localizations, metabolic pathways, predictions of protein three-dimensional structure, mapping of known single nucleotide polymorphisms (SNPs), identification of polymorphic microsatellite repeats within human genes, and comparative results with mouse full-length cDNAs. The H-InvDB analysis has shown that up to 4% of the human genome sequence (National Center for Biotechnology Information build 34 assembly) may contain misassembled or missing regions. We found that 6.5% of the human gene candidates (1,377 loci) did not have a good protein-coding open reading frame, of which 296 loci are strong candidates for non-protein-coding RNA genes. In addition, among 72,027 uniquely mapped SNPs and insertions/deletions localized within human genes, 13,215 nonsynonymous SNPs, 315 nonsense SNPs, and 452 indels occurred in coding regions. Together with 25 polymorphic microsatellite repeats present in coding regions, they may alter protein structure, causing phenotypic effects or resulting in disease. The H-InvDB platform represents a substantial contribution to resources needed for the exploration of human biology and pathology.
18.	Niessen, Peter, et al. (författare) Recent results from the amanda experiment 2003 Ingår i: Proceedings of 38th Rencontres de Moriond on Electroweak Interactions and Unified Theories 15-22 Mar 2003. Les Arcs, France. Konferensbidrag (refereegranskat)abstract AMANDA (Antarctic Muon And Neutrino Detector Array) is a neutrino telescope built under the southern polar icecap and its scope is to explore the possibility to detect high energy cosmic neutrinos. This should generate insight into the powerful celestial objects where acceleration mechanisms can bring up to 10 20 eV. We describe the achievements and results from the AMANDA-B10 prototype and the preliminary results from the current AMANDA-II detector which show dramatic increase in sensitivity.
19.	Edsjö, Joakim, et al. (författare) WIMP searches with AMANDA-B10 2001 Ingår i: The Identification Of Dark Matter. - : World Scientific. - 9789810246020 ; , s. 499-505 Bokkapitel (övrigt vetenskapligt/konstnärligt)
20.	Ahrens, J., et al. (författare) Limits to the muon flux from WIMP annihilation in the center of the Earth with the AMANDA detector 2002 Ingår i: Physical Review D. - : American Physical Society. - 1550-7998 .- 1550-2368. ; 66:3, s. 032006- Tidskriftsartikel (refereegranskat)abstract A search for nearly vertical up-going muon-neutrinos from neutralino annihilations in the center of the Earth has been performed with the AMANDA-B10 neutrino detector. The data collected in 130.1 days of live time in 1997, ∼10 9 events, have been analyzed for this search. No excess over the expected atmospheric neutrino background has been observed. An upper limit at 90% confidence level has been obtained on the annihilation rate of neutralinos in the center of the Earth, as well as the corresponding muon flux limit, both as a function of the neutralino mass in the range 100 GeV-5000 GeV. © 2002 The American Physical Society.
21.	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.
22.	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.
23.	Alonso, J. M., et al. (författare) Genome-wide Insertional mutagenesis of Arabidopsis thaliana 2003 Ingår i: Science. - 0036-8075 .- 1095-9203. ; 301:5633, s. 653-657 Tidskriftsartikel (refereegranskat)
24.	Gonzalez, I, et al. (författare) New nomenclature and DNA testing guidelines for myotonic dystrophy type 1 (DM1). The International Myotonic Dystrophy Consortium (IDMC) 2000 Ingår i: Neurology. - : Ovid Technologies (Wolters Kluwer Health). - 0028-3878 .- 1526-632X. ; 54:6, s. 1218-1221 Tidskriftsartikel (refereegranskat)
25.	Wijesooriya, K, et al. (författare) Polarization measurements in high-energy deuteron photodisintegration 2001 Ingår i: Physical Review Letters. - : American Physical Society. - 0031-9007 .- 1079-7114. ; 86:14, s. 2975-2979 Tidskriftsartikel (refereegranskat)abstract We present measurements of the recoil proton polarization for the d(γ⃗,p⃗)n reaction at θc.m. = 90° for photon energies up to 2.4 GeV. These are the first data in this reaction for polarization transfer with circularly polarized photons. The induced polarization py vanishes above 1 GeV, contrary to meson-baryon model expectations, in which resonances lead to large polarizations. However, the polarization transfer Cx does not vanish above 1 GeV, inconsistent with hadron helicity conservation. Thus, we show that the scaling behavior observed in the d(γ,p)ncross sections is not a result of perturbative QCD. These data should provide important tests of new nonperturbative calculations in the intermediate energy regime.
26.	Giorgi, F., et al. (författare) Chapter 10 of the IPCC TAR (Climate Change 2001: The Scientific Basis) 2001 Ingår i: Chapter 10-Regional Climate Information Evaluation and Projections, Cambridge University Press, Cambridge, UK. ; , s. 584-638 Bokkapitel (övrigt vetenskapligt/konstnärligt)
27.	Gayou, O, et al. (författare) Measurement of G(Ep)/G(Mp) in (e)over-right-arrowp -> e(p)over-right-arrow to Q(2)=5.6 GeV2 2002 Ingår i: Physical Review Letters. - 1079-7114. ; 88:9 Tidskriftsartikel (refereegranskat)abstract The ratio of the electric and magnetic form factors of the proton G(Ep)/G(Mp), which is an image of its charge and magnetization distributions, was measured at the Thomas Jefferson National Accelerator Facility (JLab) using the recoil polarization technique. The ratio of the form factors is directly proportional to the ratio of the transverse to longitudinal components of the polarization of the recoil proton in the elastic (e) over right arrowp --> e (p) over right arrow reaction. The new data presented span the range 3.5 < Q(2) < 5.6 GeV2 and are well described by a linear Q(2) fit. Also, the ratio rootQ(2) F-2p/F-1p reaches a constant value above Q(2) = 2 GeV2.
28.	Hoieggen, A., et al. (författare) The impact of serum uric acid on cardiovascular outcomes in the LIFE study 2004 Ingår i: Kidney Int. - 0085-2538. ; 65:3, s. 1041-9 Tidskriftsartikel (refereegranskat)abstract BACKGROUND: The Losartan Intervention For Endpoint reduction in hypertension (LIFE) study demonstrated the superiority of a losartan-based regimen over atenolol-based regimen for reduction of cardiovascular (CV) morbidity and mortality. It has been suggested that the LIFE study results may be related to the effects of losartan on serum uric acid (SUA). SUA has been proposed as an independent risk factor for CV morbidity and death. METHODS: Cox regression analysis was used to assess relationship of SUA and treatment regimens with the LIFE primary composite outcome (CV death, fatal or nonfatal myocardial infarction, fatal or nonfatal stroke). RESULTS: Baseline SUA was significantly associated with increased CV events [hazard ratio (HR) 1.024 (95% CI 1.017-1.032) per 10 micromol/L, P < 0.0001] in the entire study population. The association was significant in women [HR = 1.025 (1.013-1.037), P < 0.0001], but not in men [HR = 1.009 (0.998-1.019), P= 0.108]. After adjustment for Framingham risk score (FRS), SUA was no longer significant in the entire study population [HR = 1.006 (0.998-1.014), P= 0.122] or in men [HR = 1.006 (0.995-1.017), P= 0.291], but was significant in women [HR = 1.013 (1-1.025), P= 0.0457]. The baseline-to-end-of-study increase in SUA (standard deviation, SD) was greater (P < 0.0001) in atenolol-treated subjects (44.4 +/- 72.5 micromol/L) than in losartan-treated subjects (17.0 +/- 69.8 micromol/L). SUA as a time-varying covariate was strongly associated with events (P < 0.0001) in the entire population. The contribution of SUA to the treatment effect of losartan on the primary composite end point was 29% (14%-107%), P= 0.004. The association between time-varying SUA and increased CV risk tended to be stronger in women (P < 0.0001) than in men (P= 0.0658), although the gender-outcome interaction was not significant (P= 0.079). CONCLUSION: The increase in SUA over 4.8 years in the LIFE study was attenuated by losartan compared with atenolol treatment, appearing to explain 29% of the treatment effect on the primary composite end point. The association between SUA and events was stronger in women than in men with or without adjustment of FRS.
29.	Schulte, EC, et al. (författare) High energy angular distribution measurements of the exclusive deuteron photodisintegration reaction 2002 Ingår i: Physical Review C (Nuclear Physics). - : American Physical Society. - 0556-2813 .- 1089-490X. ; 66:4 Tidskriftsartikel (refereegranskat)abstract The first complete measurements of the angular distributions of the two-body deuteron photodisintegration differential cross section at photon energies above 1.6 GeV were performed at the Thomas Jefferson National Accelerator Facility. The results show a persistent forward-backward asymmetry up to E-gamma=2.4 GeV, the highest-energy measured in this experiment. The Hard Rescattering and the Quark-Gluon string models are in fair agreement with the results.
30.	Wong, Gane Ka-Shu, et al. (författare) A genetic variation map for chicken with 2.8 million single-nucleotide polymorphisms. 2004 Ingår i: Nature. - : Springer Science and Business Media LLC. - 1476-4687 .- 0028-0836. ; 432:7018, s. 717-22 Tidskriftsartikel (refereegranskat)
31.	Carpten, JD, et al. (författare) HRPT2, encoding parafibromin, is mutated in hyperparathyroidism-jaw tumor syndrome 2002 Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 32:4, s. 676-680 Tidskriftsartikel (refereegranskat)abstract We report here the identification of a gene associated with the hyperparathyroidism-jaw tumor (HPT-JT) syndrome. A single locus associated with HPT-JT (HRPT2) was previously mapped to chromosomal region 1q25-q32. We refined this region to a critical interval of 12 cM by genotyping in 26 affected kindreds. Using a positional candidate approach, we identified thirteen different heterozygous, germline, inactivating mutations in a single gene in fourteen families with HPT-JT. The proposed role of HRPT2 as a tumor suppressor was supported by mutation screening in 48 parathyroid adenomas with cystic features, which identified three somatic inactivating mutations, all located in exon 1. None of these mutations were detected in normal controls, and all were predicted to cause deficient or impaired protein function. HRPT2 is a ubiquitously expressed, evolutionarily conserved gene encoding a predicted protein of 531 amino acids, for which we propose the name parafibromin. Our findings suggest that HRPT2 is a tumor-suppressor gene, the inactivation of which is directly involved in predisposition to HPT-JT and in development of some sporadic parathyroid tumors.
32.	Chen, C. N., et al. (författare) Aggregate manganese Schiff base moieties by terephthalate or acetate : Dinuclear manganese and trinuclear mixed metal Mn-2/Na complexes 2003 Ingår i: Inorganic Chemistry. - : American Chemical Society (ACS). - 0020-1669 .- 1520-510X. ; 42:11, s. 3540-3548 Tidskriftsartikel (refereegranskat)abstract A reaction system consisting of terephthalic acid, NaOH, inorganic Mn(II) or Mn(III) salt, and salicylidene alkylimine resulted in dinuclear manganese complexes (salpn)(2)Mn-2(mu-phth)(CH3OH)(2) (1, salpn = N,N'-1,3-propylene-bis(salicylideneiminato); phth = terephthalate dianion), (salen)(2)Mn-2(mu-phth)(CH3OH)(2) (2, salen = N,N'-ethylene-bis(salicylideneiminato)), (salen)(2)Mn-2(mu-phth)(CH3OH)(H2O) (3), and (salen)(2)Mn-2(mu-phth) (4), while the absence of NaOH in the reaction led to a mononuclear Mn complex (salph)Mn(CH3OH)(NO3) (5, salph = N,N'-1,2-phenylene-bis(salicylideneiminato)). In addition, a trinuclear mixed metal complex H{Mn2Na(salpn)(2)(mu-OAc)(2)(H2O)(2)}(OAc)(2) (6) was obtained from the reaction system by using maleic acid instead of terephthalic acid. Five-coordinate Mn ions were found in 4 giving rise to an intermolecular interaction and constructing a one-dimensional linear structure. Antiferromagnetic exchange interactions were observed for 1-3, and a total ferromagnetic exchange of 4 was considered to stem from intermolecular magnetic coupling. H-1 NMR signals of phenolate ring and alkylene (or phenylene) backbone of the diamine are similar to those reported in the literature, and the phth protons are at -2.3 to -10.1 ppm. Studies on structure, bond valence sum analysis, and magnetic properties indicate the oxidation states of the Mn ions in 6 to be +3, which are also indicated by ESR spectra in dual mode. Ferromagnetic exchange interaction between the Mn(III) sites was observed with J = 1.74 cm(-1). A quasireversible redox pair at -0.29V/0.12V has been assigned to the redox of Mn-2(III)/Mn(III)Mn(II), implying the intactness of the complex backbone in solution.
33.	Chou, Y.-C., et al. (författare) Integration of Supply Chain Scheduling by Constraint Satisfactory 2004 Konferensbidrag (refereegranskat)
34.	Dutta, D, et al. (författare) Nuclear transparency with the gamma n ->pi(-)p process in He-4 2003 Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 68:2: 021001 Tidskriftsartikel (refereegranskat)abstract We have measured the nuclear transparency of the fundamental process gamman-->pi(-)p in He-4. These measurements were performed at Jefferson Lab in the photon energy range of 1.6-4.5 GeV and at theta(cm)(pi)=70degrees and 90degrees. These measurements are the first of their kind in the study of nuclear transparency in photoreactions. They also provide a benchmark test of Glauber calculations based on traditional models of nuclear physics. The transparency results suggest deviations from the traditional nuclear physics picture. The momentum transfer dependence of the measured nuclear transparency is consistent with Glauber calculations that include the quantum chromodynamics phenomenon of color transparency.
35.	He, C. J., et al. (författare) An unusual cyclization in a bis(cysteinyl-S) diiron complex related to the active site of Fe-only hydrogenases 2004 Ingår i: Angewandte Chemie International Edition. - : Wiley. - 1433-7851 .- 1521-3773. ; 43:27, s. 3571-3574 Tidskriftsartikel (refereegranskat)
36.	Hoieggen, A, et al. (författare) The impact of serum uric acid on cardiovascular outcomes in the LIFE study 2004 Ingår i: Kidney international. - : Elsevier BV. - 0085-2538. ; 65:3, s. 1041-1049 Tidskriftsartikel (refereegranskat)
37.	Li, Z-F, et al. (författare) Determination of carrier-transfer length from side-wall quantum well to quantum wire by micro-photoluminescence scanning 2003 Ingår i: Journal of Electronic Materials. - : Springer Science Business Media. - 0361-5235 .- 1543-186X. ; 32:8, s. 913-916 Tidskriftsartikel (refereegranskat)abstract Micro-photoluminescence (mu-PL) line scanning across a single V-groove, GaAs/AlGaAs quantum wire (QWR) has been performed at room temperature, revealing a clear spatial-dependence of the PL. After fitting each PL spectrum by multi-Gaussian line shapes, intensity profiles of each PL component from confined structures have been obtained as functions of the scanning position. The PL quenching of a side-wall quantum well (SQWL) has been recognized in a certain area in the vicinity of the QWR and is interpreted by carrier transfer into the QWR within effective transfer length. By simulating the carrier-transfer process from SQWL to QWR as a convolution of a step function for carrier distribution and a Gaussian function for exciting laser irradiance, the effective transfer length of about 1.8+/-0.3 mum has, therefore, been concluded.
38.	Ma, C. B., et al. (författare) Structural transformation mediated by o-, m-, and p-phthalates from two to three dimensions for manganese/phthalate/4,4 '-bpy complexes (4,4 '-bpy=4,4 '-bipyridine) 2003 Ingår i: New Journal of Chemistry. - : Royal Society of Chemistry (RSC). - 1144-0546 .- 1369-9261. ; 27:5, s. 890-894 Tidskriftsartikel (refereegranskat)abstract Three isomers of o-, m-, and p-phthalate are used to link together Mn centres, resulting in [Mn(phth)(H2O)(x)](n) moieties ( phth = phthalate dianion) with single-chain, double-chain and sheet structures, respectively, which predetermine the extended structures derived from the crosslinkage of 4,4'-bipyridine, and show the influence of isomerism of the phthalate on topological changes of the final polymers from two dimensional (2D) single-layer, double-layer to 3D network architectures. These structural changes in topology are correlated with the differences in the magnetic and optical properties of the polymers.
39.	Meng, H, et al. (författare) Tetramethylpentacene: Remarkable absence of steric effect on field effect mobility. 2003 Ingår i: Advanced Materials. - : Wiley. - 1521-4095 .- 0935-9648. ; 15:13, s. 1090-1093 Tidskriftsartikel (refereegranskat)
40.	Zhu, LY, et al. (författare) Cross-section measurement of charged-pion photoproduction from hydrogen and deuterium 2003 Ingår i: Physical Review Letters. - 1079-7114. ; 91:2: 022003 Tidskriftsartikel (refereegranskat)abstract We have measured the differential cross section for the gamman-->pi(-)p and gammap-->pi(+)n reactions at theta(c.m.)=90degrees in the photon energy range from 1.1 to 5.5 GeV at Jefferson Lab (JLab). The data at E(gamma)greater than or similar to3.3 GeV exhibit a global scaling behavior for both pi(-) and pi(+) photoproduction, consistent with the constituent counting rule and the existing pi(+) photoproduction data. Possible oscillations around the scaling value are suggested by these new data. The data show enhancement in the scaled cross section at a center-of-mass energy near 2.2 GeV. The cross section ratio of exclusive pi(-) to pi(+) photoproduction at high energy is consistent with the prediction based on one-hard-gluon-exchange diagrams.
41.	Heyns, M, et al. (författare) Scaling of high-k dielectrics towards sub-Inm EOT 2003 Ingår i: Proceedings of International Symposium on VLSI Technology, Systems, and Applications. ; , s. 247-250 Konferensbidrag (refereegranskat)
42.	Pignatelli, B, et al. (författare) Nitrated and oxidized plasma proteins in smokers and lung cancer patients 2001 Ingår i: Cancer research. - 0008-5472. ; 61:2, s. 778-784 Tidskriftsartikel (refereegranskat)
43.	Simonian, HP, et al. (författare) Multichannel electrogastrography (EGG) in normal subjects: a multicenter study 2004 Ingår i: Digestive diseases and sciences. - : Springer Science and Business Media LLC. - 0163-2116. ; 49:4, s. 594-601 Tidskriftsartikel (refereegranskat)
44.	Wang, M., et al. (författare) Salen-type zirconium complexes with a labile coordination site and a robust skeleton : crystal structure of (t-Bu-4-salen)ZrCl2(H2O) 2004 Ingår i: Journal of Organometallic Chemistry. - : Elsevier BV. - 0022-328X .- 1872-8561. ; 689:7, s. 1212-1217 Tidskriftsartikel (refereegranskat)abstract Treatment of LZrCl2 (L - N, N'-ethylenebis(3,5-di-tert-butylsalicylideneiminato) (1), N, N'-o-phenylenebis(3,5-di-tert-butylsalicylideneiminato) (2)), which is an effective catalyst precursor for ethylene oligomerization, with 1.5 equiv of water in toluene afforded H2O-coordinating salen-type zirconium complexes [LZrCl2(H2O)]. The effects of the content of H2O and the temperature on the equilibrium of association and disassociation of H2O molecule in [LZrCl2(H2O)(n)] (n = 0, 1) were studied in solution (CDCl3) by H-1 NMR spectroscopy. The crystal and molecular structure of [1(H2O)] was determined by X-ray diffraction analysis, which revealed that a herringbone supramolecular assembly was constructed in the crystalline state of [1(H2O)], stacked by the intermolecular hydrogen bonds between the OH group of the coordinating H2O and one of the chloride ligands.
45.	Wijesooriya, K, et al. (författare) Polarization measurements in neutral pion photoproduction 2002 Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 66:3 Tidskriftsartikel (refereegranskat)abstract We present measurements of the recoil proton polarization for the H-1((γ) over right arrow,(p) over right arrow)pi(0) reaction for theta(c.m.)(pi) = 60degrees-135degrees and for photon energies up to 4.1 GeV. These are the first data in this reaction for polarization transfer with circularly polarized photons. Various theoretical models are compared with the results. No evidence for hadron helicity conservation is observed. Models that employ factorization are not favored. It appears from the strong angular dependence of the induced polarization at photon energies of 2.5 and 3.1 GeV that a relatively high spin resonance or background amplitude might exist in this energy region.
46.	Buyanova, Irina A., et al. (författare) Optical properties of GaNAs/GaAs structures 2001 Ingår i: Materials Science & Engineering. - 0921-5107 .- 1873-4944. ; 82:1-3, s. 143-147 Tidskriftsartikel (refereegranskat)abstract We review our recent results on optical characterization of MBE-grown GaNAs/GaAs quantum structures with N content up to 4.5%, by employing photoluminescence (PL), PL excitation, and time-resolved PL spectroscopies. The dominant PL mechanism has been determined as recombination of excitons trapped by potential fluctuations of the band edge, due to composition disorder and strain nonuniformity of the alloy. The estimated value of the localization potential is around 60 meV for the low-temperature grown structures and can be reduced by increasing the growth temperature or using post-growth rapid thermal annealing (RTA). © 2001 Elsevier Science S.A.
47.	Buyanova, Irina A., et al. (författare) Strain relaxation in GaNxP1-x alloy : Effect on optical properties 2001 Ingår i: Physica. B, Condensed matter. - : Elsevier. - 0921-4526 .- 1873-2135. ; 308-310, s. 106-109 Tidskriftsartikel (refereegranskat)abstract By using scanning electron microscopy and cathodoluminescence (CL), a decrease in radiative efficiency of GaNP alloy with increasing N content is seen due to the formation of structural defects. The defect formation is attributed to relaxation of tensile strain in the GaNP layer, which is lattice mismatched to GaP substrate. Several types of extended defects including dislocations, microcracks and pits are revealed in partly relaxed GaNxP1-x epilayers with x=1.9%, whereas coherently strained layers exhibit high crystalline quality for x up to 4%. According to the CL measurements, all extended defects act as competing, non-radiative channels leading to the observed strong decrease in the radiative efficiency. From CL mapping experiments, non-uniformity of strain distribution around the extended defects is partly responsible for the broadening of the photoluminescence (PL) spectra recorded in the macro-PL experiments. © 2001 Elsevier Science B.V. All rights reserved.
48.	Buyanova, Irina, 1960-, et al. (författare) Analysis of band anticrossing in GaNxP1-x alloys 2004 Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 70, s. 085209- Tidskriftsartikel (refereegranskat)abstract Temperature-dependent absorption, photoluminescence excitation, and spectroscopic ellipsometry measurements are employed to accurately determine compositional and temperature dependences of the conduction band (CB) states in GaNP alloys. The CB edge and the higher lying Γc CB minimum (CBM) are shown to exhibit an apparently anticrossing behavior, i.e., the N-induced redshift of the bandgap energy is accompanied by a matching blueshift of the Γc CBM. The obtained data can be phenomenologically described by the band anticrossing model. By considering strong temperature dependence of the energy of the interacting N level, which has largely been overlooked in earlier studies of GaNP, the interacting N level can be attributed to the isolated substitutional NP and the coupling parameter is accurately determined.
49.	Buyanova, Irina, 1960-, et al. (författare) Band alignment in the GaNAs/GaAs quantum structures 2001 Konferensbidrag (refereegranskat)abstract The band alignment in the GaN_xAs_1-x/GaAs quantum well (QW) structures with low N composition is studied by employing time-resolved photoluminescence (PL) spectroscopy, PL polarization measurements and optically-detected cyclotron resonance (ODCR) studies. The type I band line-up is concluded based on the following experimental results. Firstly, radiative lifetime of the near band gap PL emission in the GaNAs/GaAs MQW structures is nearly identical to that for the spatially direct PL transitions in the GaNAs epilayers. Secondly, the observed polarization of the PL emission in GaNAs QWs (preferentially along the growth direction) is more consistent with the type I band line-up in the GaNAs/GaAs QWs. Thirdly, since the ODCR peaks arising from the free electrons and free holes in GaAs disappear under resonant excitation of the GaNAs MQWs, the photo-excited holes are spatially confined within the GaNAs layers under the resonant excitation condition.
50.	Buyanova, Irina, 1960-, et al. (författare) Compositional Dependence of conduction band states in GaNP alloys 2004 Ingår i: 5th International Conference on Low Dimensional Structures and Devices,2004. ; , s. 64- Konferensbidrag (övrigt vetenskapligt/konstnärligt)

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