Showing papers by "University of Ioannina published in 2011"
TL;DR: Bayesian methodology offers a multitude of ways to present results from MTM models, as it enables a natural and easy estimation of all measures based on probabilities, ranks, or predictions.
2,337 citations
TL;DR: A genetic risk score based on 29 genome-wide significant variants was associated with hypertension, left ventricular wall thickness, stroke and coronary artery disease, but not kidney disease or kidney function, and these findings suggest potential novel therapeutic pathways for cardiovascular disease prevention.
Abstract: Blood pressure is a heritable trait(1) influenced by several biological pathways and responsive to environmental stimuli. Over one billion people worldwide have hypertension (>= 140 mm Hg systolic blood pressure or >= 90 mm Hg diastolic blood pressure)(2). Even small increments in blood pressure are associated with an increased risk of cardiovascular events(3). This genome-wide association study of systolic and diastolic blood pressure, which used a multi-stage design in 200,000 individuals of European descent, identified sixteen novel loci: six of these loci contain genes previously known or suspected to regulate blood pressure (GUCY1A3-GUCY1B3, NPR3-C5orf23, ADM, FURIN-FES, GOSR2, GNAS-EDN3); the other ten provide new clues to blood pressure physiology. A genetic risk score based on 29 genome-wide significant variants was associated with hypertension, left ventricular wall thickness, stroke and coronary artery disease, but not kidney disease or kidney function. We also observed associations with blood pressure in East Asian, South Asian and African ancestry individuals. Our findings provide new insights into the genetics and biology of blood pressure, and suggest potential novel therapeutic pathways for cardiovascular disease prevention.
1,829 citations
TL;DR: The combined effect of prospective studies and clinical trials showed that adherence to the Mediterranean diet was associated with reduced risk of MS, and results from epidemiological studies also confirmed those of clinical trials.
961 citations
TL;DR: In this article, the transverse momentum balance in dijet and γ/Z+jets events is used to measure the jet energy response in the CMS detector, as well as the transversal momentum resolution.
Abstract: Measurements of the jet energy calibration and transverse momentum resolution in CMS are presented, performed with a data sample collected in proton-proton collisions at a centre-of-mass energy of 7TeV, corresponding to an integrated luminosity of 36pb−1. The transverse momentum balance in dijet and γ/Z+jets events is used to measure the jet energy response in the CMS detector, as well as the transverse momentum resolution. The results are presented for three different methods to reconstruct jets: a calorimeter-based approach, the ``Jet-Plus-Track'' approach, which improves the measurement of calorimeter jets by exploiting the associated tracks, and the ``Particle Flow'' approach, which attempts to reconstruct individually each particle in the event, prior to the jet clustering, based on information from all relevant subdetectors
750 citations
TL;DR: Findings show that collaboration and social negotiation are not only limited to the participants of an EVE, but exist between participants and avatars, offering a new dimension to computer assisted learning.
Abstract: This study is a ten-year critical review of empirical research on the educational applications of Virtual Reality (VR). Results show that although the majority of the 53 reviewed articles refer to science and mathematics, researchers from social sciences also seem to appreciate the educational value of VR and incorporate their learning goals in Educational Virtual Environments (EVEs). Although VR supports multisensory interaction channels, visual representations predominate. Few are the studies that incorporate intuitive interactivity, indicating a research trend in this direction. Few are the settings that use immersive EVEs reporting positive results on users' attitudes and learning outcomes, indicating that there is a need for further research on the capabilities of such systems. Features of VR that contribute to learning such as first order experiences, natural semantics, size, transduction, reification, autonomy and presence are exploited according to the educational context and content. Presence seems to play an important role in learning and it is a subject needing further and intensive studies. Constructivism seems to be the theoretical model the majority of the EVEs are based on. The studies present real world, authentic tasks that enable context and content dependent knowledge construction. They also provide multiple representations of reality by representing the natural complexity of the world. Findings show that collaboration and social negotiation are not only limited to the participants of an EVE, but exist between participants and avatars, offering a new dimension to computer assisted learning. Little can yet be concluded regarding the retention of the knowledge acquired in EVEs. Longitudinal studies are necessary, and we believe that the main outcome of this study is the future research perspectives it brings to light.
740 citations
TL;DR: The main findings are that socio-economic drivers have favoured land cover changes contributing to increasing fire hazard in the last decades, and large wildfires are becoming more frequent and increased fire frequency is promoting homogeneous landscapes covered by fire-prone shrublands.
662 citations
TL;DR: In this article, the authors studied the effect of collision centrality on the transverse momentum of PbPb collisions at the LHC with a data sample of 6.7 inverse microbarns.
Abstract: Jet production in PbPb collisions at a nucleon-nucleon center-of-mass energy of 2.76 TeV was studied with the CMS detector at the LHC, using a data sample corresponding to an integrated luminosity of 6.7 inverse microbarns. Jets are reconstructed using the energy deposited in the CMS calorimeters and studied as a function of collision centrality. With increasing collision centrality, a striking imbalance in dijet transverse momentum is observed, consistent with jet quenching. The observed effect extends from the lower cut-off used in this study (jet transverse momentum = 120 GeV/c) up to the statistical limit of the available data sample (jet transverse momentum approximately 210 GeV/c). Correlations of charged particle tracks with jets indicate that the momentum imbalance is accompanied by a softening of the fragmentation pattern of the second most energetic, away-side jet. The dijet momentum balance is recovered when integrating low transverse momentum particles distributed over a wide angular range relative to the direction of the away-side jet.
621 citations
TL;DR: Recommendations for vaccination in patients with AIIRD based on the currently available evidence and expert opinion were formulated, and more research is needed, particularly regarding the incidence of vaccine-preventable infectious diseases and the safety of vaccination in Patients with A IIRD.
Abstract: Objectives To develop evidence-based European League Against Rheumatism (EULAR) recommendations for vaccination in patients with autoimmune infl ammatory rheumatic diseases (AIIRD). Methods A EULAR task force was composed of experts representing 11 European countries, consisting of eight rheumatologists, four clinical immunologists, one rheumatologist/clinical immunologist, one infectious disease physician, one nephrologist, one paediatrician/ rheumatologist and one clinical epidemiologist. Key questions were formulated and the eligible spectrum of AIIRD, immunosuppressive drugs and vaccines were defi ned in order to perform a systematic literature review. A search was made of Medline from 1966 to October 2009 as well as abstracts from the EULAR meetings of 2008 and 2009 and the American College of Rheumatology (ACR) meetings of 2007 and 2008. Evidence was graded in categories I–IV, the strength of recommendations was graded in categories A–D and Delphi voting was applied to determine the level of agreement between the experts of the task force. Results Eight key questions and 13 recommendations addressing vaccination in patients with AIIRD were formulated. The strength of each recommendation was determined. Delphi voting revealed a very high level of agreement with the recommendations among the experts of the task force. Finally, a research agenda was proposed. Conclusion Recommendations for vaccination in patients with AIIRD based on the currently available evidence and expert opinion were formulated. More research is needed, particularly regarding the incidence of vaccine-preventable infectious diseases and the safety of vaccination in patients with AIIRD.
592 citations
TL;DR: Overall, antipsychotic drugs were significantly more effective than mood stabilisers, and haloperidol should be considered as among the best of the available options for the treatment of manic episodes.
505 citations
TL;DR: In this paper, a number of acoustic emission indices are proposed to classify the cracks according to their mode, which can provide a warning against the final failure of a concrete structure during bending.
496 citations
TL;DR: The current state of knowledge on the role of ROS-induced oxidative stress in altering the genetic and epigenetic involvement during human carcinogenesis is reviewed.
Abstract: Cancer is a multistage and complex process characterized by molecular alterations that underlie all three phases of its development: (i) initiation, (ii) promotion and (iii) progression. Some of these molecular events include alterations in gene expression that are regulated by both genetic and epigenetic mechanisms. On the other hand, "oxidative stress" implies a cellular state where ROS production exceeds the cell's ability to metabolize them resulting in excessive accumulation of ROS that overwhelms cellular defenses. Such state has been shown to regulate both genetic and epigenetic cascades underlying altered gene expression in human disease including cancer. Throughout this manuscript, we review the current state of knowledge on the role of ROS-induced oxidative stress in altering the genetic and epigenetic involvement during human carcinogenesis.
TL;DR: In this paper, the authors investigated whether regulations have an independent effect on bank risk-taking or whether their effect is channeled through the market power possessed by banks and found that banks with market power tend to take on lower credit risk and have a lower probability of default.
TL;DR: The review addresses the problems that might be related to the repeated treated wastewater release in the environment for reuse applications in respect to the wastewater residual load in heavy metals, accumulating in soil and plants and especially in their edible parts, in xenobiotic compounds.
TL;DR: In this article, the authors used approximately 18,000 annual observations on euro area banks over the period 2001-2008 and presented strong empirical evidence that low interest rates indeed increase bank risk-taking substantially.
Abstract: A recent line of research views the low interest-rate environment of the early to mid 2000s as an element that triggered increased risk-taking appetite of banks in search for yield. This paper uses approximately 18000 annual observations on euro area banks over the period 2001-2008 and presents strong empirical evidence that low-interest rates indeed increase bank risk-taking substantially. This result is robust across a number of different specifications that account, inter alia, for the potential endogeneity of interest rates and/or the dynamics of bank risk. Notably, among the banks of the large euro area countries this effect is less pronounced for French institutions, which held on average a relatively low level of risk assets. Finally, the distributional effects of interest rates on bank risk-taking due to individual bank characteristics reveal that the impact of interest rates on risk assets is diminished for banks with higher equity capital and is amplified for banks with higher off-balance sheet items. © 2010 Elsevier B.V.
TL;DR: Of the two essential oils TEO was more effective as was MAP2 over MAP1 for lamb meat preservation as well as modified atmosphere packaging, the combined effect of TEO and MAP2 on shelf life extension of lamb meat was evaluated.
TL;DR: In this paper, a search for events with jets and missing transverse energy is performed in a data sample of pp collisions collected at 7 TeV by the CMS experiment at the LHC.
Abstract: A search for events with jets and missing transverse energy is performed in a data sample of pp collisions collected at sqrt(s) = 7 TeV by the CMS experiment at the LHC. The analyzed data sample corresponds to an integrated luminosity of 1.14 inverse femtobarns. In this search, a kinematic variable, alphaT, is used as the main discriminator between events with genuine and misreconstructed missing transverse energy. No excess of events over the standard model expectation is found. Exclusion limits in the parameter space of the constrained minimal supersymmetric extension of the standard model are set. In this model, squark masses below 1.1 TeV are excluded at 95% CL. Gluino masses below 1.1 TeV are also ruled out at 95% CL for values of the universal scalar mass parameter below 500 GeV.
Mayo Clinic1, Norwegian University of Science and Technology2, Goethe University Frankfurt3, National Research Council4, Stellenbosch University5, University of Milano-Bicocca6, University of Antwerp7, Flanders Institute for Biotechnology8, French Institute of Health and Medical Research9, university of lille10, CERETETH11, University of Thessaly12, Pierre-and-Marie-Curie University13, Casa Sollievo della Sofferenza14, Michael J. Fox Foundation15, GlaxoSmithKline16, Juntendo University17, University of Ioannina18, Stanford University19, Medical University of Silesia20, Seoul National University Hospital21, Hallym University22, University of Lübeck23, University of Tübingen24, Academy of Athens25, Centre national de la recherche scientifique26, National Taiwan University27, Mater Misericordiae University Hospital28, Griffith University29, Lund University30, University of Queensland31, Yonsei University32, University of British Columbia33, Karolinska Institutet34
TL;DR: The results for LRRK2 show that several rare and common genetic variants in the same gene can have independent effects on disease risk, and are important in the cause and pathogenesis of PD in a greater proportion of patients with this disease than previously believed.
Abstract: Summary Background The leucine-rich repeat kinase 2 gene (LRRK2) harbours highly penetrant mutations that are linked to familial parkinsonism. However, the extent of its polymorphic variability in relation to risk of P arkinson’s disease (PD) has not been assessed systematically. We therefore assessed the frequency of LRRK2 exonic variants in individuals with and without PD, to investigate the role of the variants in PD susceptibility. Methods LRRK2 was genotyped in patients with PD and controls from three series (white, Asian, and Arab–Berber) from sites participating in the Genetic Epidemiology of Parkinson ’s Disease Consortium. Genotyping was done for exonic variants of LRRK2 that were identifi ed through searches of literature and the personal communications of consortium members. Associations with PD were assessed by use of logistic regression models. For variants that had a minor allele frequency of 0·5% or greater, single variant associations were assessed, whereas for rarer variants information was collapsed across variants. Findings 121 exonic LRRK2 variants were assessed in 15 540 individuals: 6995 white patients with PD and 5595 controls, 1376 Asian patients and 962 controls, and 240 Arab–Berber patients and 372 controls. After exclusion of carriers of known pathogenic mutations, new independent risk associations were identifi ed for polymorphic variants in white individuals (M1646T, odds ratio 1·43, 95% CI 1·15–1·78; p=0·0012) and Asian individuals (A419V, 2·27, 1·35–3·83; p=0·0011). A protective haplotype (N551K-R1398H-K1423K) was noted at a frequency greater than 5% in the white and Asian series, with a similar fi nding in the Arab–Berber series (combined odds ratio 0·82, 0·72–0·94; p=0·0043). Of the two previously reported Asian risk variants, G2385R was associated with disease (1·73, 1·20–2·49; p=0·0026), but no association was noted for R1628P (0·62, 0·36–1·07; p=0·087). In the Arab–Berber series, Y2189C showed potential evidence of risk association with PD (4·48, 1·33–15·09; p=0·012). Interpretation The results for LRRK2 show that several rare and common genetic variants in the same gene can have independent eff ects on disease risk. LRRK2, and the pathway in which it functions, is important in the cause and pathogenesis of PD in a greater proportion of patients with this disease than previously believed. These results will help discriminate those patients who will benefi t most from therapies targeted at LRRK2 pathogenic activity.
TL;DR: Overall, thyroid dysfunction should be taken into account when evaluating and treating dyslipidemic patients and subclinical hypothyroidism should be treated.
Abstract: Thyroid dysfunction has a great impact on lipids as well as a number of other cardiovascular risk factors. Hypothyroidism is relatively common and is associated with an unfavorable effect on lipids. Substitution therapy is bene- ficial for patients with overt hypothyroidism, improving lipid profile. However, whether subclinical hypothyroidism should be treated or not is a matter of debate. On the other hand, hyperthyroidism can be associated with acquired hypo- cholesterolemia or unexplained improvement of lipid profile. Overall, thyroid dysfunction should be taken into account when evaluating and treating dyslipidemic patients.
Broad Institute1, Harvard University2, deCODE genetics3, Duke University4, Paris 12 Val de Marne University5, University of Melbourne6, Columbia University7, Massachusetts Eye and Ear Infirmary8, University of Ioannina9, Washington University in St. Louis10, Queen's University Belfast11, University of Iceland12, Genentech13, Erasmus University Rotterdam14, Tufts University15
TL;DR: The novel variants identified in this study suggest that angiogenesis (VEGFA) and extracellular collagen matrix (FRK/COL10A1) pathways contribute to the development of advanced AMD.
Abstract: Despite significant progress in the identification of genetic loci for age-related macular degeneration (AMD), not all of the heritability has been explained. To identify variants which contribute to the remaining genetic susceptibility, we performed the largest meta-analysis of genome-wide association studies to date for advanced AMD. We imputed 6 036 699 single-nucleotide polymorphisms with the 1000 Genomes Project reference genotypes on 2594 cases and 4134 controls with follow-up replication of top signals in 5640 cases and 52 174 controls. We identified two new common susceptibility alleles, rs1999930 on 6q21-q22.3 near FRK/COL10A1 [odds ratio (OR) 0.87; P = 1.1 × 10(-8)] and rs4711751 on 6p12 near VEGFA (OR 1.15; P = 8.7 × 10(-9)). In addition to the two novel loci, 10 previously reported loci in ARMS2/HTRA1 (rs10490924), CFH (rs1061170, and rs1410996), CFB (rs641153), C3 (rs2230199), C2 (rs9332739), CFI (rs10033900), LIPC (rs10468017), TIMP3 (rs9621532) and CETP (rs3764261) were confirmed with genome-wide significant signals in this large study. Loci in the recently reported genes ABCA1 and COL8A1 were also detected with suggestive evidence of association with advanced AMD. The novel variants identified in this study suggest that angiogenesis (VEGFA) and extracellular collagen matrix (FRK/COL10A1) pathways contribute to the development of advanced AMD.
TL;DR: The current knowledge on DNA damage induced by endogenously produced reactive aldehydes in relation to the pathophysiology of human diseases is discussed.
Abstract: DNA damage plays a major role in various pathophysiological conditions including carcinogenesis, aging, inflammation, diabetes and neurodegenerative diseases. Oxidative stress and cell processes such as lipid peroxidation and glycation induce the formation of highly reactive endogenous aldehydes that react directly with DNA, form aldehyde-derived DNA adducts and lead to DNA damage. In occasion of persistent conditions that influence the formation and accumulation of aldehyde-derived DNA adducts the resulting unrepaired DNA damage causes deregulation of cell homeostasis and thus significantly contributes to disease phenotype. Some of the most highly reactive aldehydes produced endogenously are 4-hydroxy-2-nonenal, malondialdehyde, acrolein, crotonaldehyde and methylglyoxal. The mutagenic and carcinogenic effects associated with the elevated levels of these reactive aldehydes, especially, under conditions of stress, are attributed to their capability of causing directly modification of DNA bases or yielding promutagenic exocyclic adducts. In this review, we discuss the current knowledge on DNA damage induced by endogenously produced reactive aldehydes in relation to the pathophysiology of human diseases.
TL;DR: High catastrophizing levels were found to be associated with increased pain severity, increased incidence of development of chronic pain, and poorer quality of life after surgery.
Abstract: Background Postsurgical pain is a major cause of delayed recovery and discharge after surgery. A significant proportion of patients develop chronic postsurgical pain, which affects their quality of life. Cognitive and psychological factors are reported to play a significant role in the severity of reported postsurgical pain. High levels of catastrophizing are associated with a heightened pain experience and appear to contribute to the development of chronic pain. This article describes the concept of pain catastrophizing, its association with postsurgical pain, and its potential role in the management of postsurgical pain and postsurgical quality of life. Methods Data for this review were identified from MEDLINE, EMBASE, and PsycINFO. Reference lists of selected articles were cross-searched for additional literature. Results High catastrophizing levels were found to be associated with increased pain severity, increased incidence of development of chronic pain, and poorer quality of life after surgery. There was no consensus on the relation between catastrophizing and analgesia consumption. Conclusions Identifying and reducing catastrophizing levels can help to optimize pain management in surgical patients.
Vardan Khachatryan, Albert M. Sirunyan, Armen Tumasyan, Wolfgang Adam1 +2193 more•Institutions (152)
TL;DR: In this article, the authors measured the Upsilon production cross section in proton-proton collisions at 7 TeV using a data sample collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 3.1 +/- 0.81 nb.
Abstract: The Upsilon production cross section in proton-proton collisions at sqrt(s) = 7 TeV is measured using a data sample collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 3.1 +/- 0.3 inverse picobarns. Integrated over the rapidity range |y|<2, we find the product of the Upsilon(1S) production cross section and branching fraction to dimuons to be sigma(pp to Upsilon(1S) X) B(Upsilon(1S) to mu+ mu-) = 7.37 +/- 0.13^{+0.61}_{-0.42}\pm 0.81 nb, where the first uncertainty is statistical, the second is systematic, and the third is associated with the estimation of the integrated luminosity of the data sample. This cross section is obtained assuming unpolarized Upsilon(1S) production. If the Upsilon(1S) production polarization is fully transverse or fully longitudinal the cross section changes by about 20%. We also report the measurement of the Upsilon(1S), Upsilon(2S), and Upsilon(3S) differential cross sections as a function of transverse momentum and rapidity.
TL;DR: In this article, a comprehensive overview of the actual knowledge on the atmospheric pollution sources, transport, transformation and levels in the East Mediterranean is provided, focusing both on the background atmosphere and on the similarities and differences between the urban areas that exhibited important urbanization the past years: the two megacities Istanbul, Cairo and the Athens extended area.
TL;DR: This work constructs traversable wormholes in dilatonic Einstein-Gauss-Bonnet theory in four spacetime dimensions, and demonstrates linear stability with respect to radial perturbations for a subset of these wormholes.
Abstract: We construct traversable wormholes in dilatonic Einstein-Gauss-Bonnet theory in four spacetime dimensions, without needing any form of exotic matter. We determine their domain of existence, and show that these wormholes satisfy a generalized Smarr relation. We demonstrate linear stability with respect to radial perturbations for a subset of these wormholes.
TL;DR: This study confirms that pregnancy in women with history of breast cancer is safe and does not compromise their overall survival, and breast cancer survivors should not be denied the opportunity of future conception.
TL;DR: In this paper, a measurement of W and Z production cross sections in pp collisions at 7 TeV is presented, where electron and muon decay channels are analyzed in a data sample collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 36 inverse picobarns.
Abstract: A measurement of inclusive W and Z production cross sections in pp collisions at sqrt(s)=7 TeV is presented. The electron and muon decay channels are analyzed in a data sample collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 36 inverse picobarns. The measured inclusive cross sections are sigma(pp-> WX) B(W-> l nu) = 10.30 +/- 0.02 (stat.) +/- 0.10 (syst.) +/- 0.10 (th.) +/- 0.41 (lumi.) nb and sigma(pp -> ZX) B(Z-> l^+l^-) = 0.974 +/- 0.007 (stat.) +/- 0.007 (syst.) +/- 0.018 (th.) +/- 0.039 (lumi.) nb, limited to the dilepton invariant mass range 60 to 120 GeV. The luminosity-independent cross section ratios are [sigma(pp->WX) B(W-> l nu)]/[sigma(pp-> ZX) B(Z->l^+l^-)] = 10.54 +/- 0.07 (stat.) +/- 0.08 (syst.) +/- 0.16 (th.) and [sigma(pp->W^+X) B(W^+ -> l^+nu)] / [sigma(pp->W^- X) B(W^- -> l^- nu)] = 1.421 +/- 0.006 (stat.) +/- 0.014 (syst.) +/- 0.029 (th.). The measured values agree with next-to-next-to-leading order QCD cross section calculations based on recent parton distribution functions.
Vardan Khachatryan, Albert M. Sirunyan, Armen Tumasyan, Wolfgang Adam1 +2184 more•Institutions (150)
TL;DR: In this article, the W and Z boson production cross sections in pp collisions at 7 TeV are presented, based on 2.9 inverse picobarns of data recorded by the CMS detector at the LHC.
Abstract: Measurements of inclusive W and Z boson production cross sections in pp collisions at sqrt(s)=7 TeV are presented, based on 2.9 inverse picobarns of data recorded by the CMS detector at the LHC. The measurements, performed in the electron and muon decay channels, are combined to give sigma(pp to WX) times B(W to muon or electron + neutrino) = 9.95 \pm 0.07(stat.) \pm 0.28(syst.) \pm 1.09(lumi.) nb and sigma(pp to ZX) times B(Z to oppositely charged muon or electron pairs) = 0.931 \pm 0.026(stat.) \pm 0.023(syst.) \pm 0.102(lumi.) nb. Theoretical predictions, calculated at the next-to-next-to-leading order in QCD using recent parton distribution functions, are in agreement with the measured cross sections. Ratios of cross sections, which incur an experimental systematic uncertainty of less than 4%, are also reported.
01 Mar 2011
TL;DR: A fully automated method for cell nuclei detection in Pap smear images that includes a priori knowledge about the circumference of each nucleus and the application of classification algorithms.
Abstract: In this paper, we present a fully automated method for cell nuclei detection in Pap smear images. The locations of the candidate nuclei centroids in the image are detected with morphological analysis and they are refined in a second step, which incorporates a priori knowledge about the circumference of each nucleus. The elimination of the undesirable artifacts is achieved in two steps: the application of a distance-dependent rule on the resulted centroids; and the application of classification algorithms. In our method, we have examined the performance of an unsupervised (fuzzy C-means) and a supervised (support vector machines) classification technique. In both classification techniques, the effect of the refinement step improves the performance of the clustering algorithm. The proposed method was evaluated using 38 cytological images of conventional Pap smears containing 5617 recognized squamous epithelial cells. The results are very promising, even in the case of images with high degree of cell overlapping.
Vardan Khachatryan, Milan Nikolic1, Robin Erbacher1, C. A. Carrillo Montoya +2169 more•Institutions (155)
TL;DR: In this article, a search for supersymmetry with R-parity conservation in proton-proton collisions at a centre-of-mass energy of 7 TeV is presented.
TL;DR: In this paper, a comparison of the relative yields of upsilon resonances in the mu(+) mu(-) decay channel in PbPb and pp collisions at a centre-of-mass energy per nucleon pair of 2.76 TeV, is performed with data collected with the CMS detector at the LHC.
Abstract: A comparison of the relative yields of Upsilon resonances in the mu(+) mu(-) decay channel in PbPb and pp collisions at a centre-of-mass energy per nucleon pair of 2.76 TeV, is performed with data collected with the CMS detector at the LHC. Using muons of transverse momentum above 4 GeV/c and pseudorapidity below 2.4, the double ratio of the Upsilon(2S) and Upsilon(3S) excited states to the Upsilon(1S) ground state in PbPb and pp collisions,(Upsilon(2S+3S)/Upsilon(1S)[PbPb])/(Upsilon(2S+3S)/Upsilon(1S)[pp]), is found to be 0.31 - 0.15 + 0.19 (stat.) +/- 0.03 (syst.). The probability to obtain the measured value, or lower, if the true double ratio is unity, has been calculated to be less than 1%.