| 1. |
- Abelev, Betty, et al.
(författare)
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Measurement of prompt J/psi and beauty hadron production cross sections at mid-rapidity in pp collisions at root s=7 TeV
- 2012
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Ingår i: Journal of High Energy Physics. - 1029-8479. ; :11
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Tidskriftsartikel (refereegranskat)abstract
- The ALICE experiment at the LHC has studied J/psi production at mid-rapidity in pp collisions at root s = 7 TeV through its electron pair decay on a data sample corresponding to an integrated luminosity L-int = 5.6 nb(-1). The fraction of J/psi from the decay of long-lived beauty hadrons was determined for J/psi candidates with transverse momentum p(t) > 1,3 GeV/c and rapidity vertical bar y vertical bar < 0.9. The cross section for prompt J/psi mesons, i.e. directly produced J/psi and prompt decays of heavier charmonium states such as the psi(2S) and chi(c) resonances, is sigma(prompt J/psi) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 8.3 +/- 0.8(stat.) +/- 1.1 (syst.)(-1.4)(+1.5) (syst. pol.) mu b. The cross section for the production of b-hadrons decaying to J/psi with p(t) > 1.3 GeV/c and vertical bar y vertical bar < 0.9 is a sigma(J/psi <- hB) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 1.46 +/- 0.38 (stat.)(-0.32)(+0.26) (syst.) mu b. The results are compared to QCD model predictions. The shape of the p(t) and y distributions of b-quarks predicted by perturbative QCD model calculations are used to extrapolate the measured cross section to derive the b (b) over bar pair total cross section and d sigma/dy at mid-rapidity.
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| 2. |
- Abelev, Betty, et al.
(författare)
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Long-range angular correlations on the near and away side in p-Pb collisions at root S-NN=5.02 TeV
- 2013
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Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 719:1-3, s. 29-41
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Tidskriftsartikel (refereegranskat)abstract
- Angular correlations between charged trigger and associated particles are measured by the ALICE detector in p-Pb collisions at a nucleon-nucleon centre-of-mass energy of 5.02 TeV for transverse momentum ranges within 0.5 < P-T,P-assoc < P-T,P-trig < 4 GeV/c. The correlations are measured over two units of pseudorapidity and full azimuthal angle in different intervals of event multiplicity, and expressed as associated yield per trigger particle. Two long-range ridge-like structures, one on the near side and one on the away side, are observed when the per-trigger yield obtained in low-multiplicity events is subtracted from the one in high-multiplicity events. The excess on the near-side is qualitatively similar to that recently reported by the CMS Collaboration, while the excess on the away-side is reported for the first time. The two-ridge structure projected onto azimuthal angle is quantified with the second and third Fourier coefficients as well as by near-side and away-side yields and widths. The yields on the near side and on the away side are equal within the uncertainties for all studied event multiplicity and p(T) bins, and the widths show no significant evolution with event multiplicity or p(T). These findings suggest that the near-side ridge is accompanied by an essentially identical away-side ridge. (c) 2013 CERN. Published by Elsevier B.V. All rights reserved.
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| 3. |
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| 4. |
- Abelev, Betty, et al.
(författare)
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Underlying Event measurements in pp collisions at root s=0.9 and 7 TeV with the ALICE experiment at the LHC
- 2012
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Ingår i: Journal of High Energy Physics. - 1029-8479. ; :7
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Tidskriftsartikel (refereegranskat)abstract
- We present measurements of Underlying Event observables in pp collisions at root s = 0 : 9 and 7 TeV. The analysis is performed as a function of the highest charged-particle transverse momentum p(T),L-T in the event. Different regions are defined with respect to the azimuthal direction of the leading (highest transverse momentum) track: Toward, Transverse and Away. The Toward and Away regions collect the fragmentation products of the hardest partonic interaction. The Transverse region is expected to be most sensitive to the Underlying Event activity. The study is performed with charged particles above three different p(T) thresholds: 0.15, 0.5 and 1.0 GeV/c. In the Transverse region we observe an increase in the multiplicity of a factor 2-3 between the lower and higher collision energies, depending on the track p(T) threshold considered. Data are compared to PYTHIA 6.4, PYTHIA 8.1 and PHOJET. On average, all models considered underestimate the multiplicity and summed p(T) in the Transverse region by about 10-30%.
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| 5. |
- Andrade-Pavón, Dulce, et al.
(författare)
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The 3-hydroxy-3-methylglutaryl coenzyme-A reductases from fungi: A proposal as a therapeutic target and as a study model
- 2014
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Ingår i: Revista Iberoamericana de Micologia. - : Elsevier BV. - 1130-1406 .- 2173-9188. ; 31, s. 81-85
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Tidskriftsartikel (refereegranskat)abstract
- The enzyme 3-hydroxy-3-methylglutaryl coenzyme-A reductase (HMGR) catalyzes the conversion of HMG-Co-A into mevalonate. This step is the limiting point for the synthesis of cholesterol in mammals and ergosterol in fungi. We describe in this article the genome organization of HMGR coding genes and those deduced from different fungi, recount the evidence showing statins as HMGR inhibitors for ergosterol synthesis and its effect in yeast viability, and propose fungal HMGR (HMGRf) as a model to study the use of pharmaceutical compounds to inhibit cholesterol and ergosterol synthesis. Bibliographical search and bioinformatic analyses were performed and discussed. HMGRfs belong to the class I with a high homology in the catalytic region. The sterol biosynthetic pathway in humans and fungi share many enzymes in the initial steps (such as the HMGR enzyme), but in the last steps enzymes are different rendering the two final products: cholesterol in mammals and ergosterol in fungi. With regards to inhibitors such as statins and other compounds, these affect also fungal viability. Since HMGR from Schizosaccharomyces pombe and Ustilago maydis are very similar to the human HMGR in the catalytic regions, we propose that fungal enzymes can be used to test inhibitors for a potential use in humans. We consider that HMGRf is a good therapeutic target to design and test new antifungal compounds.This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012). © 2013 Revista Iberoamericana de Micología.
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| 6. |
- Davies, Peter, et al.
(författare)
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Values and competing frameworks in conceptual change in social science
- 2012
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This paper discusses conceptual change in the Social sciences, addressing in particular issues of values and implications for teaching. The paper is a product of a symposium organised in September 2011 in Stockholm where researchers in the disciplines of economics, politics and sociology presented and discussed empirical studies on conceptual change in these domains. The current paper is a theoretical discussion which draws on the empirical evidence presented in the symposium. We concentrate on evidence from two studies. First, a study by César López examined conceptions of ‘Nation’ held by students in Spain. A second study by Thomas Philip examined the willingness of pre-service teachers in California to change their conception of the relationship between education and employability. In both cases, students’ sense of belonging and purpose appeared to be an important barrier to conceptual change.Our main focus is on the way in which both these examples may be understood as challenges to ‘Master Narratives’ in Social Science. These narratives combine sets of descriptions, explanations and judgements to provide a coherent ways of seeing the social world. Descriptive categories (such as ‘nation’ or ‘education’) carry within them implicit judgements about the worth of the category (for instance whether nationhood or education should be seen as intrinsically good/bad, problematic/unproblematic) as well as implicit explanations of how the social world operates. The challenge for conceptual change in these circumstances is a need for simultaneous change in description, explanation and judgement. We discuss this challenge in the light of evidence provided by these two studies and we conclude with some implications for teaching in social science.
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| 7. |
- Edlund, Ulrica, et al.
(författare)
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Self-assembling zwitterionic carboxybetaine copolymers via aqueous SET-LRP from hemicellulose multi-site initiators
- 2012
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Ingår i: Polymer Chemistry. - : Royal Society of Chemistry (RSC). - 1759-9954 .- 1759-9962. ; 3:10, s. 2920-2927
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Tidskriftsartikel (refereegranskat)abstract
- The zwitterionic carboxybetaines, (3-methacryloylamino-propyl)-(2-carboxy-ethyl)-dimethyl-ammonium (CBMAA-3) and (3-acryloylamino-propyl)-(2-carboxy-ethyl)-dimethyl-ammonium (CBAA-3), were successfully grafted from a galactoglucomannan macroinitiator. The macroinitiator was prepared from the hemicellulose acetylated galactoglucomannan functionalised with alpha-bromoisobutyric acid. The polymerisation of the betaines was efficiently carried out by a Cu(0) wire catalysed single electron-transfer living radical polymerisation (SET-LRP) in aqueous solution yielding water-soluble graft copolymers and nearly pseudo-first order kinetics suggesting a good degree of control over the polymerisation process. The graft copolymers spontaneously self-assembled in aqueous solution into well-defined nanoparticles highly stable in aqueous media.
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