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Operando neutron diffraction reveals mechanisms for controlled strain evolution in 3D printing. Nat Commun 2023; 14:4950. [PMID: 37587109 PMCID: PMC10432395 DOI: 10.1038/s41467-023-40456-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 07/28/2023] [Indexed: 08/18/2023] Open
Abstract
Residual stresses affect the performance and reliability of most manufactured goods and are prevalent in casting, welding, and additive manufacturing (AM, 3D printing). Residual stresses are associated with plastic strain gradients accrued due to transient thermal stress. Complex thermal conditions in AM produce similarly complex residual stress patterns. However, measuring real-time effects of processing on stress evolution is not possible with conventional techniques. Here we use operando neutron diffraction to characterize transient phase transformations and lattice strain evolution during AM of a low-temperature transformation steel. Combining diffraction, infrared and simulation data reveals that elastic and plastic strain distributions are controlled by motion of the face-centered cubic and body-centered cubic phase boundary. Our results provide a new pathway to design residual stress states and property distributions within additively manufactured components. These findings will enable control of residual stress distributions for advantages such as improved fatigue life or resistance to stress-corrosion cracking.
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P–320 Endometrial flushing to improve fertility outcomes: a systematic review and meta-analysis. Hum Reprod 2021. [DOI: 10.1093/humrep/deab130.319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Study question
Does flushing the endometrial cavity improve fertility outcomes in couples with infertility and what are the preferred flushing mediums?
Summary answer
Flushing the endometrial cavity appears to improve live birth rate, implantation rate and clinical pregnancy rate. There was no difference in miscarriage or complication rate.
What is known already
Live birth rate was improved in cleavage-stage transfer when the uterus was flushed with human chorionic gonadotropin (hCG) at a dose >500 IU in a Cochrane review (Craciunas L et al 2018). Chemical and clinical pregnancy rates and implantation rate may be improved by endometrial flushing with platelet-rich plasma (PRP) in a meta-analysis by Maleki-Hajiagha A et al 2020. Flushing the cavity with oil-based contrast at hysterosalpingography (HSG) improved pregnancy rates when compared with water-based contrast in a systematic review by Fang F et al 2018.
Study design, size, duration
Our study was a systematic review and meta-analysis. We searched MEDLINE (1946 to December 2020), Embase (1980 to December 2020), Cumulative Index to Nursing and Allied Health Literature (CINAHL) (1961 to 9 December 2020) PsychINFO (1806 to December 2020). We screened the titles of search results to identify studies for inclusion and then screened abstracts and full texts to ensure trials met search criteria.
Participants/materials, setting, methods
We included in this review all randomised controlled trials (RCTs), quasi-experimental or cohort studies evaluating intrauterine instillation or flushing with any medium, irrespective of timing of intervention and irrespective of language or country of origin. We performed the meta-analyses using a random-effects model and performed subgroup and sensitivity analysis. Two authors independently extracted the data. We calculated the risk ratio or odds ratio with 95% confidence intervals based on intention-to-treat or available data analysis.
Main results and the role of chance
We included 36 RCTs and 12 non-randomised trials including 12230 participants. The sample size varied from 15 to 1186. We included 11 comparisons. Primary outcomes were healthy baby rate and live birth rate. Healthy baby rate was not reported in any of the trials. Live birth rate favoured oil soluble contrast medium (at HSG) when compared to water based contrast medium (OR 0.64, 95% CI 0.52 to 0.78, 2 RCTs and 1 cohort study, 2050 participants, I2 = 86%) or no intervention (OR 3.53, 95% CI 1.64 to 7.60, 2 RCTs, 192 participants, I2 = 0%). With regards to our secondary outcomes: CSF instillation, HCG instillation, PRP instillation and oil-soluble contrast medium at HSG (over water-soluble contrast medium) were favoured for implantation rate and clinical pregnancy rate. There was no statistically significant difference in miscarriage or complication rate for any of the comparisons. All trials were at an overall high risk of bias when assessed on the following areas: sequence generation, allocation concealment, blinding of participants, personnel, and outcome assessors, incomplete outcome data, selective outcome reporting, and other sources of bias.
Limitations, reasons for caution
Only 36 studies included were RCTs. Twelve of the RCTs had post randomisation drop outs. There was a lack of detail on the instillation medium for several of the included studies. There was no placebo used in many of the control groups. All meta-analyses had high levels of heterogeneity.
Wider implications of the findings: Our findings are in keeping with the literature suggesting a possible improvement in live birth rate following flushing the endometrium with oil soluble contrast medium when compared with a control group. Mechanistic studies are now required to understand how oil-based medium improves fertility.
Trial registration number
NA
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Slower response to treatment of iron-deficiency anaemia in pregnant women infected with HIV: a prospective cohort study. BJOG 2021; 128:1674-1681. [PMID: 33587784 DOI: 10.1111/1471-0528.16671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/30/2021] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Antenatal anaemia is associated with increased peripartum transfusion requirement in South Africa. We studied whether HIV was associated with the response to treatment of iron-deficiency anaemia. DESIGN Prospective cohort study. SETTING Hospital-based antenatal anaemia clinic in South Africa. SAMPLE Equal-sized cohorts of pregnant women testing positive for HIV (HIV+) and testing negative for HIV (HIV-) with iron-deficiency anaemia. METHODS Haemoglobin trajectories of women with confirmed iron-deficiency anaemia (ferritin < 50 ng/ml) were estimated from the initiation of iron supplementation using mixed-effects modelling, adjusted for baseline HIV status, ferritin level, maternal and gestational ages and time-varying iron supplementation. MAIN OUTCOME MEASURES Haemoglobin trajectories. RESULTS Of 469 women enrolled, 51% were HIV+, 90% of whom were on antiretroviral therapy (with a mean CD4+ lymphocyte count of 403 cells/mm3 ). Anaemia diagnoses did not differ by HIV status. A total of 400 women with iron-deficiency anaemia were followed during treatment with oral or intravenous (6%) iron therapy. In multivariable analysis, haemoglobin recovery was 0.10 g/dl per week slower on average in women who were HIV+ versus women who were HIV- (P = 0.001), 0.01 g/dl per week slower in women with higher baseline ferritin (P < 0.001) and 0.06 g/dl per week faster in women who were compliant with oral iron therapy (P = 0.002). CONCLUSIONS Compared with women who were HIV-, women who were HIV+ with iron-deficiency anaemia had slower but successful haemoglobin recovery with iron therapy. Earlier effective management of iron deficiency could reduce the incidence of peripartum blood transfusion. TWEETABLE ABSTRACT Among pregnant women with iron-deficiency anaemia in South Africa, HIV slows haemoglobin recovery in response to oral iron therapy.
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Plasmablastic lymphoma in Johannesburg, South Africa, in the era of widescale antiretroviral therapy use. HIV Med 2020; 22:225-230. [PMID: 33022825 DOI: 10.1111/hiv.12965] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 07/20/2020] [Accepted: 08/26/2020] [Indexed: 11/28/2022]
Abstract
OBJECTIVES Plasmablastic lymphoma (PBL) is a clinically aggressive lymphoma which has a predilection for extranodal sites and is frequently HIV-associated. The incidence of non-Hodgkin lymphoma is thought to be reduced by widescale antiretroviral therapy (ART) coverage, but the literature is sparse as regards the impact of ART on the incidence of PBL and its outcomes in South Africa (SA). This study aimed to compare factors of interest in cases of PBL diagnosed before and after the widespread availability of ART in Johannesburg, SA. METHODS All cases of PBL diagnosed in the state sector hospitals of Johannesburg in 2007 and 2017 (before and after the widespread availability of ART, respectively) were extracted from the laboratory information system, and factors of interest compared. RESULTS The majority (> 95%) of cases of PBL were seen among people with HIV infection (PWH) at both time-points, and the proportion of patients on ART and with virological suppression (VS) increased significantly in 2017. However, the number of cases of PBL did not differ significantly between the two years assessed, comprising 46/397 (11.6%) and 53/582 (9.6%) of all lymphomas in 2007 and 2017, respectively (P = 0.23). Ongoing risk for PBL among PWH with virological control and immunological recovery was evident in 2017, as 18.9% of the patients had both VS and CD4 counts > 200 cells/μL at diagnosis. Inferior survival times were associated with elevated lactate dehydrogenase (LDH) levels and Epstein Barr virus (EBV) negativity, but were not influenced by the presence of AIDS, ART or VS. EBV negativity was significantly associated with VS, and appeared to flag a particularly aggressive form of the disease. CONCLUSIONS Widescale ART coverage has not reduced the incidence of PBL in Johannesburg, and an ongoing risk for this disease among PWH with adequate virological control and immunological recovery persists.
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The 2016 ENFSI Fingerprint Working Group testing programme. Forensic Sci Int 2018; 292:148-162. [PMID: 30312945 DOI: 10.1016/j.forsciint.2018.09.026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 09/16/2018] [Accepted: 09/24/2018] [Indexed: 11/18/2022]
Abstract
In 2016, the Fingerprint Working Group (EFP-WG) of the European Network of Forensic Science Institutes (ENFSI), officially established an advisory group with the task of organising proficiency tests (PTs), as well as collaborative exercises (CEs) as a way of raising standards within the fingerprint profession. This article will provide an overview of the Visualisation collaborative exercise and the Comparison proficiency test, which were carried out in 2016. Both the exercise and the test were organised and co-funded by the Prevention of and Fight against Crime Programme of the European Union [1-3], Direct Grant "Towards the Vision for European Forensic Science 2020 (TVEFS-2020)" HOME/2013/ISEC/MO/ENFSI/4000005962, work package T3 "Proficiency Tests and Collaborative Exercises for the Fingerprint Domain". The characteristics of the testing programme are summarised, followed by an overview of the knowledge that has been gained, including lessons learnt.
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Average neutron time-of-flight instrument response function inferred from single D-T neutron events within a plastic scintillator. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:10I119. [PMID: 30399763 DOI: 10.1063/1.5038883] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Accepted: 07/08/2018] [Indexed: 06/08/2023]
Abstract
The apparent ion temperature and neutron-reaction history are important characteristics of a fusion plasma. Extracting these quantities from a measured neutron-time-of-flight signal requires accurate knowledge of the instrument response function (IRF). This work describes a novel method for obtaining the IRF directly for single DT neutron interactions by utilizing n-alpha coincidence. The t(d,α)n nuclear reaction was produced at Sandia National Laboratories' Ion Beam Laboratory using a 300 keV Cockcroft-Walton generator to accelerate a 2.5 μA beam of 175 keV D+ ions into a stationary ErT2 target. The average neutron IRF was calculated by taking a time-corrected average of individual neutron events within an EJ-228 plastic scintillator. The scintillator was coupled to two independent photo-multiplier tubes operated in the current mode: a Hamamatsu 5946 mod-5 and a Photek PMT240. The experimental setup and results will be discussed.
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The 2015 ENFSI Fingerprint Working Group testing programme. Forensic Sci Int 2017; 280:55-63. [PMID: 28946033 DOI: 10.1016/j.forsciint.2017.09.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2017] [Revised: 08/31/2017] [Accepted: 09/04/2017] [Indexed: 10/18/2022]
Abstract
As early as 2004, the Fingerprint Working Group (EFP-WG) of the European Network of Forensic Science Institutes (ENFSI) has organised proficiency tests (PT's), as well as collaborative exercises (CE's), as a way of raising standards within the fingerprint profession. This article provides an overview of the three collaborative exercises carried out in 2015. The characteristics of the testing programme are summarised, followed by an overview of the knowledge that has been gained, including depicting what lessons have been learnt.
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ENFSI collaborative testing programme for fingermarks: Past experiences and future perspectives. Forensic Sci Int 2017; 275:282-301. [DOI: 10.1016/j.forsciint.2017.03.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 03/13/2017] [Accepted: 03/20/2017] [Indexed: 10/19/2022]
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Refining peripheral blood smear review rules for neonatal inpatients in a South African academic laboratory. Int J Lab Hematol 2016; 38:347-51. [PMID: 27087063 DOI: 10.1111/ijlh.12491] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 03/02/2016] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Peripheral blood smear review (PBSR) is a labour-intensive test, and skilled morphologists are in short supply. It is therefore helpful for laboratories to establish rules for PBSR to improve laboratory efficiency. Previously published guidelines in this regard are useful, but make few recommendations specific to neonates. Neonatal blood is characterized by several peculiarities which would be considered pathological if present in adults. Consequently, smear review rules (SRR) are often triggered in neonates without significant value being added on review. This study aimed to assess and fine-tune the SRR triggered in neonatal samples in order to improve laboratory efficiency. METHODS Full blood counts collected from 188 neonatal inpatients of the Chris Hani Baragwanath Academic Hospital in South Africa were retrospectively reviewed, the triggered rules documented, and the value added on PBSR determined. RESULTS Smear review rules were triggered in 148 (78.7%) samples, with significant morphological abnormalities identified in 84 (54.4%), and a false-positive rate of 34.0%. In patients with unhelpful review, the commonest rules triggered were the flags querying the presence of abnormal lymphocytes, blasts or nucleated red blood cells. When one or more of these flags were triggered in the absence of any other SRR, PBSR was always noncontributory. Disregarding these flags in the current cohort would reduce both the review and the false-positive rates by >20% without increasing the false-negative rate. CONCLUSION False-positive smear review is common in neonates, and minor modifications to SRR can substantially reduce the smear review rate without increasing the false-negative rate.
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MFN2 DELETION FOUNDER MUTATION IN THE UK POPULATION. J Neurol Psychiatry 2014. [DOI: 10.1136/jnnp-2014-309236.170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Running out of brain. J Sports Med Phys Fitness 2014; 54:370-372. [PMID: 24739301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Stroke is the third most common cause of death after coronary artery disease and cancer in the UK, and running is a popular form of exercise, and increasingly, people are participating in large scale endurance events such as marathons and half-marathons. We describe here two cases of young men suffering a stroke after running a marathon and who were subsequently found to have a patent foramen ovale (PFO). We have reviewed the existing literature concerning stroke in those undertaking long-distance running, and suggest why PFO may have been important etiologically in our two patients. We tentatively suggest that individuals with a PFO who engage in long distance running may be at increased risk of stroke, independent of other cerebrovascular risk factors.
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Inclusive search for supersymmetry using razor variables in pp collisions at √s=7 TeV. PHYSICAL REVIEW LETTERS 2013; 111:081802. [PMID: 24010428 DOI: 10.1103/physrevlett.111.081802] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Indexed: 06/02/2023]
Abstract
An inclusive search is presented for new heavy particle pairs produced in √s=7 TeV proton-proton collisions at the LHC using 4.7±0.1 fb(-1) of integrated luminosity. The selected events are analyzed in the 2D razor space of M(R), an event-by-event indicator of the heavy particle mass scale, and R, a dimensionless variable related to the missing transverse energy. The third-generation sector is probed using the event heavy-flavor content. The search is sensitive to generic supersymmetry models with minimal assumptions about the superpartner decay chains. No excess is observed in the number of events beyond that predicted by the standard model. Exclusion limits are derived in the CMSSM framework as well as for simplified models. Within the CMSSM parameter space considered, gluino masses up to 800 GeV and squark masses up to 1.35 TeV are excluded at 95% confidence level depending on the model parameters. The direct production of pairs of top or bottom squarks is excluded for masses as high as 400 GeV.
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Search for physics beyond the standard model in events with τ leptons, jets, and large transverse momentum imbalance in pp collisions at [Formula: see text]. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2013; 73:2493. [PMID: 25814865 PMCID: PMC4370880 DOI: 10.1140/epjc/s10052-013-2493-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 06/11/2013] [Indexed: 06/04/2023]
Abstract
A search for physics beyond the standard model is performed with events having one or more hadronically decaying τ leptons, highly energetic jets, and large transverse momentum imbalance. The data sample corresponds to an integrated luminosity of 4.98 fb-1 of proton-proton collisions at [Formula: see text] collected with the CMS detector at the LHC in 2011. The number of observed events is consistent with predictions for standard model processes. Lower limits on the mass of the gluino in supersymmetric models are determined.
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Search for supersymmetry in pp collisions at [Formula: see text] TeV in events with a single lepton, jets, and missing transverse momentum. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2013; 73:2404. [PMID: 25814857 PMCID: PMC4370766 DOI: 10.1140/epjc/s10052-013-2404-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Revised: 03/02/2013] [Indexed: 05/30/2023]
Abstract
Results are reported from a search for new physics processes in events containing a single isolated high-transverse-momentum lepton (electron or muon), energetic jets, and large missing transverse momentum. The analysis is based on a 4.98 fb-1 sample of proton-proton collisions at a center-of-mass energy of 7 TeV, obtained with the CMS detector at the LHC. Three separate background estimation methods, each relying primarily on control samples in the data, are applied to a range of signal regions, providing complementary approaches for estimating the background yields. The observed yields are consistent with the predicted standard model backgrounds. The results are interpreted in terms of limits on the parameter space for the constrained minimal supersymmetric extension of the standard model, as well as on cross sections for simplified models, which provide a generic description of the production and decay of new particles in specific, topology based final states. ELECTRONIC SUPPLEMENTARY MATERIAL The online version of this article (doi:10.1140/epjc/s10052-013-2404-z) contains supplementary material, which is available to authorized users.
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Search for pair-produced dijet resonances in four-jet final states in pp collisions at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2013; 110:141802. [PMID: 25166980 DOI: 10.1103/physrevlett.110.141802] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2013] [Indexed: 06/03/2023]
Abstract
A search for the pair production of a heavy, narrow resonance decaying into two jets has been performed using events collected in sqrt[s] = 7 TeV pp collisions with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 5.0 fb(-1). Events are selected with at least four jets and two dijet combinations with similar dijet mass. No resonances are found in the dijet mass spectrum. The upper limit at 95% confidence level on the product of the resonance pair production cross section, the branching fractions into dijets, and the acceptance varies from 0.22 to 0.005 pb, for resonance masses between 250 and 1200 GeV. Pair-produced colorons decaying into qq are excluded for coloron masses between 250 and 740 GeV.
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Search for contact interactions using the inclusive jetpTspectrum inppcollisions ats=7 TeV. Int J Clin Exp Med 2013. [DOI: 10.1103/physrevd.87.052017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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A guide for identification and continuing care of adult congenital heart disease patients in primary care. Int J Cardiol 2013; 163:260-265. [DOI: 10.1016/j.ijcard.2011.06.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Accepted: 06/05/2011] [Indexed: 11/26/2022]
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Search for pair production of third-generation leptoquarks and top squarks in pp collisions at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2013; 110:081801. [PMID: 23473129 DOI: 10.1103/physrevlett.110.081801] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Indexed: 06/01/2023]
Abstract
Results are presented from a search for the pair production of third-generation scalar and vector leptoquarks, as well as for top squarks in R-parity-violating supersymmetric models. In either scenario, the new, heavy particle decays into a τ lepton and a b quark. The search is based on a data sample of pp collisions at sqrt[s] = 7 TeV, which is collected by the CMS detector at the LHC and corresponds to an integrated luminosity of 4.8 fb(-1). The number of observed events is found to be in agreement with the standard model prediction, and exclusion limits on mass parameters are obtained at the 95% confidence level. Vector leptoquarks with masses below 760 GeV are excluded and, if the branching fraction of the scalar leptoquark decay to a τ lepton and a b quark is assumed to be unity, third-generation scalar leptoquarks with masses below 525 GeV are ruled out. Top squarks with masses below 453 GeV are excluded for a typical benchmark scenario, and limits on the coupling between the top squark, τ lepton, and b quark, λ(333)(') are obtained. These results are the most stringent for these scenarios to date.
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Measurement of the Υ1S, Υ2S, and Υ3S polarizations in pp collisions at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2013; 110:081802. [PMID: 23473130 DOI: 10.1103/physrevlett.110.081802] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Indexed: 06/01/2023]
Abstract
The polarizations of the Υ(1S), Υ(2S), and Υ(3S) mesons are measured in proton-proton collisions at sqrt[s] = 7 TeV, using a data sample of Υ(nS) → μ +μ- decays collected by the CMS experiment, corresponding to an integrated luminosity of 4.9 fb(-1). The dimuon decay angular distributions are analyzed in three different polarization frames. The polarization parameters λ[symbol see text], λ(φ), and λ([symbol see text]φ), as well as the frame-invariant quantity λ, are presented as a function of the Υ(nS) transverse momentum between 10 and 50 GeV, in the rapidity ranges |y|<0.6 and 0.6<|y|<1.2. No evidence of large transverse or longitudinal polarizations is seen in the explored kinematic region.
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Measurement of the sum of WW and WZ production with W+dijet events in pp collisions at [Formula: see text]. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2013; 73:2283. [PMID: 25814853 PMCID: PMC4370803 DOI: 10.1140/epjc/s10052-013-2283-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 12/20/2012] [Indexed: 06/02/2023]
Abstract
A measurement of the inclusive WW+WZ diboson production cross section in proton-proton collisions is reported, based on events containing a leptonically decaying W boson and exactly two jets. The data sample, collected at [Formula: see text] with the CMS detector at the LHC, corresponds to an integrated luminosity of 5.0 fb-1. The measured value of the sum of the inclusive WW and WZ cross sections is σ(pp→WW+WZ)=68.9±8.7 (stat.)±9.7 (syst.)±1.5 (lum.) pb, consistent with the standard model prediction of 65.6±2.2 pb. This is the first measurement of WW+WZ production in pp collisions using this signature. No evidence for anomalous triple gauge couplings is found and upper limits are set on their magnitudes.
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Improved excitation fidelity in cardiac imaging with 2-spoke parallel excitation at 7 Tesla. J Cardiovasc Magn Reson 2013. [PMCID: PMC3560027 DOI: 10.1186/1532-429x-15-s1-w1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Measurement of the azimuthal anisotropy of neutral pions in Pb-Pb collisions at sqrt[s](NN)] = 2.76 TeV. PHYSICAL REVIEW LETTERS 2013; 110:042301. [PMID: 25166155 DOI: 10.1103/physrevlett.110.042301] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2012] [Indexed: 06/03/2023]
Abstract
First measurements of the azimuthal anisotropy of neutral pions produced in Pb-Pb collisions at a center-of-mass energy of sqrt[s(NN)] = 2.76 TeV are presented. The amplitudes of the second Fourier component (v(2)) of the π(0) azimuthal distributions are extracted using an event-plane technique. The values of v(2) are studied as a function of the neutral pion transverse momentum (p(T)) for different classes of collision centrality in the kinematic range 1.6<p(T) <8.0 GeV/c, within the pseudorapidity interval |η|<0.8. The CMS measurements of v(2) (p(T)) are similar to previously reported π(0) azimuthal anisotropy results from sqrt[s(NN)] = 200 GeV Au-Au collisions at RHIC, despite a factor of ∼ 14 increase in the center-of-mass energy. In the momentum range 2.5<p(T)<5.0 GeV/c, the neutral pion anisotropies are found to be smaller than those observed by CMS for inclusive charged particles.
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Adolescent alcohol exposure alters the rat adult hypothalamic-pituitary-adrenal axis responsiveness in a sex-specific manner. Neuroscience 2013; 235:174-86. [PMID: 23337533 DOI: 10.1016/j.neuroscience.2012.12.069] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 12/07/2012] [Accepted: 12/17/2012] [Indexed: 01/04/2023]
Abstract
Exposure to alcohol during adolescence exerts long-term effects on the adult brain stress circuits, causing many changes that persist into adulthood. Here we examined the consequences of adolescent intermittent ethanol (AIE, administered from postnatal day (PND) 28-42) on the hypothalamic-pituitary-adrenal (HPA) axis-related brain circuitry of rats challenged with intragastric (ig) administration of alcohol in adulthood (PND 70-71). Both male and female adolescent rats were exposed to alcohol vapors, while controls did not receive the drug, to assess whether AIE alters adult alcohol response in a sex-specific manner. We demonstrated that AIE increased paraventricular nucleus (PVN) Avp mRNA levels during late (PND 42) but not middle (PND 36) adolescence in males. While an alcohol challenge administered to 70-71-day-old rats increased Crf mRNA levels in males and Avp mRNA levels in females, AIE blunted both effects. These results suggest that AIE produced long-lasting changes in the responsiveness of the HPA axis to a subsequent alcohol challenge in a sex-specific manner. Furthermore, AIE altered adrenergic brain stem nuclei involved in stress responses in adulthood, resulting in increased numbers of phenylethanolamine N-methyltransferase (PNMT) neurons in male C2 and female C1 regions. This tended to enhance activation of the male C2 nucleus upon alcohol challenge. Collectively, these results suggest that AIE exerts long-term effects on the ability of the PVN to respond to an alcohol challenge in adulthood, possibly mediated by catecholaminergic input from the brain stem to the PVN.
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Evidence for associated production of a single top quark and W boson in pp collisions at sqrt[s]=7 TeV. PHYSICAL REVIEW LETTERS 2013; 110:022003. [PMID: 23383893 DOI: 10.1103/physrevlett.110.022003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2012] [Indexed: 06/01/2023]
Abstract
Evidence is presented for the associated production of a single top quark and W boson in pp collisions at sqrt[s]=7 TeV with the CMS experiment at the LHC. The analyzed data correspond to an integrated luminosity of 4.9 fb(-1). The measurement is performed using events with two leptons and a jet originated from a b quark. A multivariate analysis based on kinematic properties is utilized to separate the tt background from the signal. The observed signal has a significance of 4.0σ and corresponds to a cross section of 16(-4)(+5) pb, in agreement with the standard model expectation of 15.6±0.4(-1.2)(+1.0) pb.
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27
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Search for heavy neutrinos and W(R) bosons with right-handed couplings in a left-right symmetric model in pp collisions at sqrt[s]=7 TeV. PHYSICAL REVIEW LETTERS 2012; 109:261802. [PMID: 23368549 DOI: 10.1103/physrevlett.109.261802] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Indexed: 06/01/2023]
Abstract
Results are presented from a search for heavy, right-handed muon neutrinos, N(μ), and right-handed W(R) bosons, which arise in the left-right symmetric extensions of the standard model. The analysis is based on a 5.0 fb(-1) sample of proton-proton collisions at a center-of-mass energy of 7 TeV, collected by the CMS detector at the Large Hadron Collider. No evidence is observed for an excess of events over the standard model expectation. For models with exact left-right symmetry, heavy right-handed neutrinos are excluded at 95% confidence level for a range of neutrino masses below the W(R) mass, dependent on the value of M(W(R)). The excluded region in the two-dimensional (M(W(R)), M(N(μ)) mass plane extends to M(W(R))=2.5 TeV.
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28
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Study of the Dijet mass spectrum in pp → W+jets events at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2012; 109:251801. [PMID: 23368450 DOI: 10.1103/physrevlett.109.251801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Indexed: 06/01/2023]
Abstract
We report an investigation of the invariant mass spectrum of the two jets with highest transverse momentum in pp → W+2-jet and W+3-jet events to look for resonant enhancement. The data sample corresponds to an integrated luminosity of 5.0 fb(-1) collected with the CMS detector at sqrt[s] = 7 TeV. We find no evidence for the anomalous structure reported by the CDF Collaboration, and establish an upper limit of 5.0 pb at 95% confidence level on the production cross section for a generic Gaussian signal with mass near 150 GeV. Additionally, we exclude two theoretical models that predict a CDF-like dijet resonance near 150 GeV.
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Measurement of the relative prompt production rate of χc2 and χc1 in pp collisions at [Formula: see text]. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2012; 72:2251. [PMID: 25814834 PMCID: PMC4370953 DOI: 10.1140/epjc/s10052-012-2251-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 11/17/2012] [Indexed: 05/28/2023]
Abstract
A measurement is presented of the relative prompt production rate of χc2 and χc1 with 4.6 fb-1 of data collected by the CMS experiment at the LHC in pp collisions at [Formula: see text]. The two states are measured via their radiative decays χc→J/ψ+γ, with the photon converting into an e+e- pair for J/ψ rapidity |y(J/ψ)|<1.0 and photon transverse momentum pT(γ)>0.5 GeV/c. The measurement is given for six intervals of pT(J/ψ) between 7 and 25 GeV/c. The results are compared to theoretical predictions.
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30
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Observation of sequential Υ suppression in PbPb collisions. PHYSICAL REVIEW LETTERS 2012; 109:222301. [PMID: 23368113 DOI: 10.1103/physrevlett.109.222301] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Indexed: 06/01/2023]
Abstract
The suppression of the individual Υ(nS) states in PbPb collisions with respect to their yields in pp data has been measured. The PbPb and pp data sets used in the analysis correspond to integrated luminosities of 150 μb(-1) and 230 nb(-1), respectively, collected in 2011 by the CMS experiment at the LHC, at a center-of-mass energy per nucleon pair of 2.76 TeV. The Υ(nS) yields are measured from the dimuon invariant mass spectra. The suppression of the Υ(nS) yields in PbPb relative to the yields in pp, scaled by the number of nucleon-nucleon collisions, R(AA), is measured as a function of the collision centrality. Integrated over centrality, the R(AA) values are 0.56±0.08(stat)±0.07(syst), 0.12±0.04(stat)±0.02(syst), and lower than 0.10 (at 95% confidence level), for the Υ(1S), Υ(2S), and Υ(3S) states, respectively. The results demonstrate the sequential suppression of the Υ(nS) states in PbPb collisions at LHC energies.
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31
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Search for new physics in the multijet and missing transverse momentum final state in proton-proton collisions at √s = 7 TeV. PHYSICAL REVIEW LETTERS 2012; 109:171803. [PMID: 23215177 DOI: 10.1103/physrevlett.109.171803] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2012] [Indexed: 06/01/2023]
Abstract
A search for physics beyond the standard model is performed in events with at least three jets and large missing transverse momentum produced in proton-proton collisions at a center-of-mass energy of √s=7 TeV. No significant excess of events above the expected backgrounds is observed in 4.98 fb(-1) of data collected with the CMS detector at the Large Hadron Collider. The results are presented in the context of the constrained minimal supersymmetric extension of the standard model and more generically for simplified models. For the simplified models of gluino-gluino and squark-squark production, gluino masses below 1.0 TeV and squark masses below 0.76 TeV are excluded in case the lightest supersymmetric particle mass is below 200 GeV. These results significantly extend previous searches.
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32
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Measurement of the pseudorapidity and centrality dependence of the transverse energy density in Pb-Pb collisions at √(s(NN))=2.76 TeV. PHYSICAL REVIEW LETTERS 2012; 109:152303. [PMID: 23102301 DOI: 10.1103/physrevlett.109.152303] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2012] [Indexed: 06/01/2023]
Abstract
The transverse energy (E(T)) in Pb-Pb collisions at 2.76 TeV nucleon-nucleon center-of-mass energy (√(s(NN)) has been measured over a broad range of pseudorapidity (η) and collision centrality by using the CMS detector at the LHC. The transverse energy density per unit pseudorapidity (dE(T)/dη) increases faster with collision energy than the charged particle multiplicity. This implies that the mean energy per particle is increasing with collision energy. At all pseudorapidities, the transverse energy per participating nucleon increases with the centrality of the collision. The ratio of transverse energy per unit pseudorapidity in peripheral to central collisions varies significantly as the pseudorapidity increases from η=0 to |η|=5.0. For the 5% most central collisions, the energy density per unit volume is estimated to be about 14 GeV/fm(3) at a time of 1 fm/c after the collision. This is about 100 times larger than normal nuclear matter density and a factor of 2.6 times higher than the energy density reported at √(s(NN))=200 GeV at the Relativistic Heavy Ion Collider.
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33
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Search for a W' or techni-ρ decaying into WZ in pp Collisions at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2012; 109:141801. [PMID: 23083236 DOI: 10.1103/physrevlett.109.141801] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2012] [Indexed: 06/01/2023]
Abstract
A search is performed in pp collisions at sqrt[s]=7 TeV for exotic particles decaying via WZ to final states with electrons and muons. The data sample corresponds to an integrated luminosity of approximately 5 fb(-1). No significant excess is observed in the data above the expected standard model background. Upper bounds at 95% confidence level are set on the production cross section of the W' boson described by the sequential standard model and on the W' WZ coupling. W' bosons with masses below 1143 GeV are excluded. Limits are also set in the context of low-scale technicolor models, under a range of assumptions concerning the model parameters.
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34
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Search for a light pseudoscalar Higgs boson in the dimuon decay channel in pp collisions at √s = 7 TeV. PHYSICAL REVIEW LETTERS 2012; 109:121801. [PMID: 23005937 DOI: 10.1103/physrevlett.109.121801] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Indexed: 06/01/2023]
Abstract
The dimuon invariant mass spectrum is searched in the range between 5.5 and 14 GeV for a light pseudoscalar Higgs boson a, predicted in a number of new physics models, including the next-to-minimal supersymmetric standard model. The data sample used in the search corresponds to an integrated luminosity of 1.3 fb(-1) collected in pp collisions at √s = 7 TeV with the CMS detector at the LHC. No excess is observed above the background predictions and upper limits are set on the cross section times branching fraction σ × B(pp→a→μ(+)μ(-)) in the range of 1.5-7.5 pb. These results improve on existing bounds on the abb coupling for m(a) < m(Υ(1S)) and are the first significant limits for m(a) > m(Υ(3S)). Constraints on the supersymmetric parameter space are presented in the context of the next-to-minimal model.
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35
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Measurement of the electron charge asymmetry in inclusive W production in pp collisions at sqrt[s]=7 TeV. PHYSICAL REVIEW LETTERS 2012; 109:111806. [PMID: 23005617 DOI: 10.1103/physrevlett.109.111806] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Indexed: 06/01/2023]
Abstract
A measurement of the electron charge asymmetry in inclusive pp→W+X→eν+X production at sqrt[s]=7 TeV is presented based on data recorded by the CMS detector at the LHC and corresponding to an integrated luminosity of 840 pb(-1). The electron charge asymmetry reflects the unequal production of W(+) and W(-) bosons in pp collisions. The electron charge asymmetry is measured in bins of the absolute value of electron pseudorapidity in the range of |η|<2.4. The asymmetry rises from about 0.1 to 0.2 as a function of the pseudorapidity and is measured with a relative precision better than 7%. This measurement provides new stringent constraints for parton distribution functions.
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36
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Search for new physics with same-sign isolated dilepton events with jets and missing transverse energy. PHYSICAL REVIEW LETTERS 2012; 109:071803. [PMID: 23006358 DOI: 10.1103/physrevlett.109.071803] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Indexed: 06/01/2023]
Abstract
A search for new physics is performed in events with two same-sign isolated leptons, hadronic jets, and missing transverse energy in the final state. The analysis is based on a data sample corresponding to an integrated luminosity of 4.98 fb(-1) produced in pp collisions at a center-of-mass energy of 7 TeV collected by the CMS experiment at the LHC. This constitutes a factor of 140 increase in integrated luminosity over previously published results. The observed yields agree with the standard model predictions and thus no evidence for new physics is found. The observations are used to set upper limits on possible new physics contributions and to constrain supersymmetric models. To facilitate the interpretation of the data in a broader range of new physics scenarios, information on the event selection, detector response, and efficiencies is provided.
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37
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Azimuthal anisotropy of charged particles at high transverse momenta in Pb-Pb collisions at sqrt[s(NN)] = 2.76 TeV. PHYSICAL REVIEW LETTERS 2012; 109:022301. [PMID: 23030154 DOI: 10.1103/physrevlett.109.022301] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2012] [Indexed: 06/01/2023]
Abstract
The azimuthal anisotropy of charged particles in Pb-Pb collisions at sqrt[s(NN)]=2.76 TeV is measured with the CMS detector at the LHC over an extended transverse momentum (p(T)) range up to approximately 60 GeV/c. The data cover both the low-p(T) region associated with hydrodynamic flow phenomena and the high-p(T) region where the anisotropies may reflect the path-length dependence of parton energy loss in the created medium. The anisotropy parameter (v2) of the particles is extracted by correlating charged tracks with respect to the event-plane reconstructed by using the energy deposited in forward-angle calorimeters. For the six bins of collision centrality studied, spanning the range of 0-60% most-central events, the observed v2 values are found to first increase with p(T), reaching a maximum around p(T)=3 GeV/c, and then to gradually decrease to almost zero, with the decline persisting up to at least pp(T)=40 GeV/c over the full centrality range measured.
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38
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Search for dark matter and large extra dimensions in pp collisions yielding a photon and missing transverse energy. PHYSICAL REVIEW LETTERS 2012; 108:261803. [PMID: 23004964 DOI: 10.1103/physrevlett.108.261803] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Indexed: 06/01/2023]
Abstract
Results are presented from a search for new physics in the final state containing a photon (γ) and missing transverse energy (E[combininb /](T)). The data correspond to an integrated luminosity of 5.0 fb(-1) collected in pp collisions at √[s]=7 TeV by the CMS experiment. The observed event yield agrees with standard-model expectations for the γ+E[combininb /](T) events. Using models for the production of dark-matter particles (χ), we set 90% confidence level (C.L.) upper limits of 13.6-15.4 fb on χ production in the γ+E[combininb /](T) state. These provide the most sensitive upper limits for spin-dependent χ-nucleon scattering for χ masses (M(χ)) between 1 and 100 GeV. For spin-independent contributions, the present limits are extended to M(χ)<3.5 GeV. For models with 3-6 large extra dimensions, our data exclude extra-dimensional Planck scales between 1.64 and 1.73 TeV at 95% C.L.
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39
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Abstract
The observation of a new b baryon via its strong decay into Ξ(b)(-) π(+) (plus charge conjugates) is reported. The measurement uses a data sample of pp collisions at sqrt[s] = 7 TeV collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 5.3 fb(-1). The known Ξ(b)(-) baryon is reconstructed via the decay chain Ξ(b)(-) → J/ψΞ(-) → μ(+) μ(-) Λ(0) π(-), with Λ(0) → pπ(-). A peak is observed in the distribution of the difference between the mass of the Ξ(b)(-) π(+) system and the sum of the masses of the Ξ(b)(-) and π(+), with a significance exceeding 5 standard deviations. The mass difference of the peak is 14.84 ± 0.74(stat) ± 0.28(syst) MeV. The new state most likely corresponds to the J(P) = 3/2(+) companion of the Ξ(b).
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40
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Measurement of thett¯production cross section in pp collisions ats=7 TeVin dilepton final states containing aτ. Int J Clin Exp Med 2012. [DOI: 10.1103/physrevd.85.112007] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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41
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Abstract
There is emerging data that patterns of motor activity early in neonatal life can predict impairments in neuromotor development. However, current techniques to monitor infant movement mainly rely on observer scoring, a technique limited by skill, fatigue, and inter-rater reliability. Consequently, we tested the use of a lightweight, wireless, accelerometer system that measures movement and can be worn by premature babies without interfering with routine care. We hypothesized that this system would be useful in assessing motor activity, in identifying abnormal movement, and in reducing the amount of video that a clinician would need to review for abnormal movements. Ten preterm infants in the NICU were monitored for 1 h using both the accelerometer system and video. A physical therapist trained to recognize cramped-synchronized general movements scored all of the video data by labeling each abnormal movement observed. The parameters of three different computer models were then optimized based on correlating features computed from accelerometer data and the observer’s annotations. The annotations were compared to the model’s prediction on unseen data. The trained observer identified cramped-synchronized general movements in 6 of the 10 infants. The computer models attained between 70% and 90% accuracy when predicting the same observer label for each data point. Our study suggests that mini-accelerometers may prove useful as a clinical tool assessing patterns of movement in preterm infants.
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42
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Search for the standard model Higgs boson in the decay channel H→ZZ→4ℓ in pp collisions at √s=7 TeV. PHYSICAL REVIEW LETTERS 2012; 108:111804. [PMID: 22540464 DOI: 10.1103/physrevlett.108.111804] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2012] [Indexed: 05/31/2023]
Abstract
A search for a Higgs boson in the four-lepton decay channel H→ZZ, with each Z boson decaying to an electron or muon pair, is reported. The search covers Higgs boson mass hypotheses in the range of 110<m(H)<600 GeV. The analysis uses data corresponding to an integrated luminosity of 4.7 fb(-1) recorded by the CMS detector in pp collisions at √s=7 TeV from the LHC. Seventy-two events are observed with four-lepton invariant mass m(4ℓ)>100 GeV (with 13 below 160 GeV), while 67.1±6.0 (9.5±1.3) events are expected from background. The four-lepton mass distribution is consistent with the expectation of standard model background production of ZZ pairs. Upper limits at 95% confidence level exclude the standard model Higgs boson in the ranges of 134-158 GeV, 180-305 GeV, and 340-465 GeV. Small excesses of events are observed around masses of 119, 126, and 320 GeV, making the observed limits weaker than expected in the absence of a signal.
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43
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Search for signatures of extra dimensions in the diphoton mass spectrum at the large hadron collider. PHYSICAL REVIEW LETTERS 2012; 108:111801. [PMID: 22540461 DOI: 10.1103/physrevlett.108.111801] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2011] [Indexed: 05/31/2023]
Abstract
A search for signatures of extra spatial dimensions in the diphoton invariant-mass spectrum has been performed with the CMS detector at the LHC. No excess of events above the standard model expectation is observed using a data sample collected in proton-proton collisions at √s=7 TeV corresponding to an integrated luminosity of 2.2 fb(-1). In the context of the large-extra-dimensions model, lower limits are set on the effective Planck scale in the range of 2.3-3.8 TeV at the 95% confidence level. These limits are the most restrictive bounds on virtual-graviton exchange to date. The most restrictive lower limits to date are also set on the mass of the first graviton excitation in the Randall-Sundrum model in the range of 0.86-1.84 TeV, for values of the associated coupling parameter between 0.01 and 0.10.
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44
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Measurement of the rapidity and transverse momentum distributions ofZbosons inppcollisions at(s)=7 TeV. Int J Clin Exp Med 2012. [DOI: 10.1103/physrevd.85.032002] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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45
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β-Nerve growth factor is a major component of alpaca seminal plasma and induces ovulation in female alpacas. Reprod Fertil Dev 2012; 24:1093-7. [DOI: 10.1071/rd12039] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 03/10/2012] [Indexed: 11/23/2022] Open
Abstract
Ovulation in camelids is induced by an unidentified protein in the seminal plasma of the male termed ‘ovulation-inducing factor’. This protein has been reported to be a 14-kDa protein under reducing conditions, which, when purified from seminal plasma, induces ovulation in llamas. The identification of this protein and investigation of its potential to induce ovulation in camelids may aid the development of protocols for the induction of ovulation. In the present study, alpaca seminal plasma proteins were separated using one-dimensional sodium dodecyl sulfate–polyacrylamide gel electrophoresis and the most abundant protein of 14 kDa was identified as β-nerve growth factor (β-NGF) by liquid chromatography mass spectrometry. Female alpacas (n = 5 per group) were given intramuscular injections of: (1) 1 mL of 0.9% saline; (2) 4 µg buserelin, a gonadotrophin-releasing hormone agonist; (3) 2 mL alpaca seminal plasma; or (4) 1 mg human β-NGF. Ovulation was detected by transrectal ultrasonography 8 days after treatment and confirmed by plasma progesterone concentrations. Ovulation occurred in 0%, 80%, 80% and 80% of animals treated with saline, buserelin, seminal plasma and β-NGF, respectively. Treatment type did not affect the diameter of the corpus luteum, but plasma progesterone concentrations were lower in saline-treated animals than in the other treatment groups owing to the lack of a corpus luteum. The present study is the first to identify the ovulation-inducing factor protein in alpacas. β-NGF successfully induces ovulation in alpacas and this finding may lead to new methods for the induction of ovulation in camelids.
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46
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Search for a vectorlike quark with charge 2/3 in t+Z events from pp collisions at √s=7 TeV. PHYSICAL REVIEW LETTERS 2011; 107:271802. [PMID: 22243304 DOI: 10.1103/physrevlett.107.271802] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Indexed: 05/31/2023]
Abstract
A search for pair-produced heavy vectorlike charge-2/3 quarks, T, in pp collisions at a center-of-mass energy of 7 TeV, is performed with the CMS detector at the LHC. Events consistent with the flavor-changing-neutral-current decay of a T quark to a top quark and a Z boson are selected by requiring two leptons from the Z-boson decay, as well as an additional isolated charged lepton. In a data sample corresponding to an integrated luminosity of 1.14 fb(-1), the number of observed events is found to be consistent with the standard model background prediction. Assuming a branching fraction of 100% for the decay T→tZ, a T quark with a mass less than 475 GeV/c(2) is excluded at the 95% confidence level.
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47
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Search for supersymmetry at the LHC in events with jets and missing transverse energy. PHYSICAL REVIEW LETTERS 2011; 107:221804. [PMID: 22182023 DOI: 10.1103/physrevlett.107.221804] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Indexed: 05/31/2023]
Abstract
A search for events with jets and missing transverse energy is performed in a data sample of pp collisions collected at √s=7 TeV by the CMS experiment at the LHC. The analyzed data sample corresponds to an integrated luminosity of 1.14 fb(-1). In this search, a kinematic variable α(T) 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% C.L. Gluino masses below 1.1 TeV are also ruled out at 95% C.L. for values of the universal scalar mass parameter below 500 GeV.
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48
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Search for new physics with a monojet and missing transverse energy in pp collisions at √s = 7 TeV. PHYSICAL REVIEW LETTERS 2011; 107:201804. [PMID: 22181725 DOI: 10.1103/physrevlett.107.201804] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Indexed: 05/31/2023]
Abstract
A study of events with missing transverse energy and an energetic jet is performed using pp collision data at a center-of-mass energy of 7 TeV. The data were collected by the CMS detector at the LHC, and correspond to an integrated luminosity of 36 pb(-1). An excess of these events over standard model contributions is a signature of new physics such as large extra dimensions and unparticles. The number of observed events is in good agreement with the prediction of the standard model, and significant extension of the current limits on parameters of new physics benchmark models is achieved.
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49
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Search for B(s)(0) → μ+ μ- and B(0) → μ+ μ- decays in pp collisions at sqrt[s] = 7 TeV. PHYSICAL REVIEW LETTERS 2011; 107:191802. [PMID: 22181597 DOI: 10.1103/physrevlett.107.191802] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Indexed: 05/31/2023]
Abstract
A search for the rare decays B(s)(0) → μ+ μ- and B(0) → μ+ μ- is performed in pp collisions at sqrt[s] = 7 TeV, with a data sample corresponding to an integrated luminosity of 1.14 fb(-1), collected by the CMS experiment at the LHC. In both cases, the number of events observed after all selection requirements is consistent with expectations from background and standard-model signal predictions. The resulting upper limits on the branching fractions are B(B(s)(0) → μ+ μ-) < 1.9 × 10(-8) and B(B(0) → μ+ μ-)<4.6 × 10(-9), at 95% confidence level.
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50
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Measurement of the inclusive jet cross section in pp collisions at √s = 7 TeV. PHYSICAL REVIEW LETTERS 2011; 107:132001. [PMID: 22026843 DOI: 10.1103/physrevlett.107.132001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Indexed: 05/31/2023]
Abstract
The inclusive jet cross section is measured in pp collisions with a center-of-mass energy of 7 TeV at the Large Hadron Collider using the CMS experiment. The data sample corresponds to an integrated luminosity of 34 pb(-1). The measurement is made for jet transverse momenta in the range 18-1100 GeV and for absolute values of rapidity less than 3. The measured cross section extends to the highest values of jet p(T) ever observed and, within the experimental and theoretical uncertainties, is generally in agreement with next-to-leading-order perturbative QCD predictions.
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