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1.
Eur J Neurol ; 27(1): 92-99, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31304648

RESUMO

BACKGROUND AND PURPOSE: The cervical and thoracic cross-sectional spinal cord area (CS-SCA) in multiple sclerosis (MS) correlates with disability, whilst such a correlation remains to be established in neuromyelitis optica spectrum disorder (NMOSD). Our aim was to clarify differences between MS and NMOSD in spinal cord segments where CS-SCA is associated with disability. METHODS: The CS-SCA at C2/C3, C3/C4, T8/T9 and T9/T10 vertebral disc levels was measured in 140 MS patients (111 with relapsing-remitting MS and 29 with progressive MS) and 42 NMOSD patients with anti-aquaporin-4 immunoglobulin G. Disability was evaluated by Expanded Disability Status Scale (EDSS) scores. Multivariate associations between CS-SCA and disability were assessed by stepwise forward multiple linear regression. RESULTS: Thoracic CS-SCA was significantly smaller in NMOSD patients than in MS patients even after adjusting for age, sex and disease duration (P = 0.002 at T8/T9), whilst there was no difference in cervical CS-SCA between the two diseases. Cervical and thoracic CS-SCA had a negative correlation with EDSS scores in MS patients (P < 0.0001 at C3/C4 and P = 0.0002 at T8/T9) whereas only thoracic CS-SCA correlated with EDSS scores in NMOSD patients (P = 0.0006 at T8/T9). By multiple regression analyses, predictive factors for disability in MS were smaller cervical CS-SCA, progressive course, older age and a higher number of relapses, whilst those in NMOSD were smaller thoracic CS-SCA and older age. CONCLUSIONS: Thoracic CS-SCA is a useful predictive marker for disability in patients with NMOSD whilst cervical CS-SCA is associated with disability in patients with MS.


Assuntos
Esclerose Múltipla/patologia , Neuromielite Óptica/patologia , Medula Espinal/patologia , Adulto , Fatores Etários , Idoso , Atrofia/diagnóstico por imagem , Atrofia/patologia , Estudos Transversais , Pessoas com Deficiência , Progressão da Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico por imagem , Neuromielite Óptica/diagnóstico por imagem , Medula Espinal/diagnóstico por imagem
2.
Nano Lett ; 19(9): 5915-5919, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31373825

RESUMO

Diamond has two crystallographically inequivalent sites in the unit cell. In doped diamond, dopant occupation in the two sites is expected to be equal. Nevertheless, preferential dopant occupation during growth under nonequilibrium conditions is of fundamental importance, for example, to enhance the properties of nitrogen-vacancy (N-V) centers; therefore, this is a promising candidate for a qubit. However, the lack of suitable experimental techniques has made it difficult to study the crystal- and chemical-site-resolved local structures of dopants. Here, we confirm the identity of two chemical sites with asymmetric dopant incorporation in the diamond structure, via the photoelectron holography (PEH) of heavily phosphorus (P)-doped diamond prepared by chemical vapor deposition. One is substitutionally incorporated P with preferential site occupations and the other can be attributed to a PV split vacancy complex with preferential orientation. The present study shows that PEH is a valuable technique to study the local structures around dopants with a resolution of crystallographically inequivalent but energetically equivalent sites/orientations. Such information provides strategies to improve the properties of dopant related-complexes in which alignment is crucial for sensing of magnetic field or quantum spin register using N-V centers in diamond.

3.
Phys Rev Lett ; 120(14): 142301, 2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29694144

RESUMO

The relative yields of ϒ mesons produced in pp and Pb-Pb collisions at sqrt[s_{NN}]=5.02 TeV and reconstructed via the dimuon decay channel are measured using data collected by the CMS experiment. Double ratios are formed by comparing the yields of the excited states, ϒ(2S) and ϒ(3S), to the ground state, ϒ(1S), in both Pb-Pb and pp collisions at the same center-of-mass energy. The double ratios, [ϒ(nS)/ϒ(1S)]_{Pb-Pb}/[ϒ(nS)/ϒ(1S)]_{pp}, are measured to be 0.308±0.055(stat)±0.019(syst) for the ϒ(2S) and less than 0.26 at 95% confidence level for the ϒ(3S). No significant ϒ(3S) signal is found in the Pb-Pb data. The double ratios are studied as a function of collision centrality, as well as ϒ transverse momentum and rapidity. No significant dependencies are observed.

4.
Haemophilia ; 24(5): e328-e337, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29902361

RESUMO

INTRODUCTION: Immune tolerance induction (ITI) was the primary therapeutic approach to eradicate inhibitors in haemophilia patients. Several large ITI registries had been reported, but successful predictors of ITI outcome are still debated. No reports are available on large ITI studies in non-caucasian countries. AIM: We designed a retrospective cohort study of ITI in Japanese haemophilia patients with inhibitor. METHODS: Retrospective data were collected from 155 haemophilia (H)A (140 severe-type) and 7 HB (7 severe-type) patients treated at 45 institutions. ITI outcome was centrally reviewed. We defined "success" as undetectable inhibitor after 2 consecutive measurements. RESULTS: The ITI success rate was 71.2% for HA and 83.3% for HB. Cumulated success rates for HA achieving 50% and 75% were 0.7 and 2 years after treatment, respectively. Significant successful predictors in HA were low-responding inhibitors compared to high-responding inhibitors, shorter time to the start of ITI, and lower historical and treatment peak titres of inhibitor. Dose regimen (high dose; ≥90 IU/kg every day, low dose; ≤75 IU/kg, 3 d/wk) and the type of therapeutic product did not affect outcomes. The success rate of salvage ITI using von Willebrand factor-containing factor VIII was 50% (n = 6/12), and patient age at the start of salvage ITI was a significant predictor. The inhibitor recurred in 6 HA cases (3.9%). CONCLUSION: The results provided potentially important information for improving future success rates for ITI in inhibitor patients.


Assuntos
Hemofilia A/imunologia , Tolerância Imunológica/imunologia , Pré-Escolar , Estudos de Coortes , Feminino , Hemofilia A/tratamento farmacológico , Humanos , Japão , Masculino , Estudos Retrospectivos , Resultado do Tratamento
5.
Phys Rev Lett ; 119(8): 082301, 2017 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-28952777

RESUMO

The production of jets in association with Z bosons, reconstructed via the µ^{+}µ^{-} and e^{+}e^{-} decay channels, is studied in pp and, for the first time, in Pb-Pb collisions. Both data samples were collected by the CMS experiment at the LHC, at a nucleon-nucleon center-of-mass energy of 5.02 TeV. The Pb-Pb collisions were analyzed in the 0%-30% centrality range. The back-to-back azimuthal alignment was studied in both pp and Pb-Pb collisions for Z bosons with transverse momentum p_{T}^{Z}>60 GeV/c and a recoiling jet with p_{T}^{jet}>30 GeV/c. The p_{T} imbalance x_{jZ}=p_{T}^{jet}/p_{T}^{Z}, as well as the average number of jet partners per Z, R_{jZ}, was studied in intervals of p_{T}^{Z}. The R_{jZ} is found to be smaller in Pb-Pb than in pp collisions, which suggests that in Pb-Pb collisions a larger fraction of partons associated with the Z bosons fall below the 30 GeV/c p_{T}^{jet} threshold because they lose energy.

6.
Phys Rev Lett ; 118(16): 162301, 2017 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-28474955

RESUMO

The relative modification of the prompt ψ(2S) and J/ψ yields from pp to PbPb collisions, at the center-of-mass energy of 5.02 TeV per nucleon pair, is presented. The analysis is based on pp and PbPb data samples collected by the CMS experiment at the LHC in 2015, corresponding to integrated luminosities of 28.0 pb^{-1} and 464 µb^{-1}, respectively. The double ratio of measured yields of prompt charmonia reconstructed through their decays into muon pairs, (N_{ψ(2S)}/N_{J/ψ})_{PbPb}/(N_{ψ(2S)}/N_{J/ψ})_{pp}, is determined as a function of PbPb collision centrality and charmonium transverse momentum p_{T}, in two kinematic intervals: |y|<1.6 covering 6.5

7.
Phys Rev Lett ; 118(12): 122301, 2017 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-28388204

RESUMO

Charge-dependent azimuthal particle correlations with respect to the second-order event plane in p-Pb and PbPb collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV have been studied with the CMS experiment at the LHC. The measurement is performed with a three-particle correlation technique, using two particles with the same or opposite charge within the pseudorapidity range |η|<2.4, and a third particle measured in the hadron forward calorimeters (4.4<|η|<5). The observed differences between the same and opposite sign correlations, as functions of multiplicity and η gap between the two charged particles, are of similar magnitude in p-Pb and PbPb collisions at the same multiplicities. These results pose a challenge for the interpretation of charge-dependent azimuthal correlations in heavy ion collisions in terms of the chiral magnetic effect.

8.
Phys Rev Lett ; 119(14): 141802, 2017 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-29053305

RESUMO

A search for charged Higgs bosons produced via vector boson fusion and decaying into W and Z bosons using proton-proton collisions at sqrt[s]=13 TeV is presented. The data sample corresponds to an integrated luminosity of 15.2 fb^{-1} collected with the CMS detector in 2015 and 2016. The event selection requires three leptons (electrons or muons), two jets with large pseudorapidity separation and high dijet mass, and missing transverse momentum. The observation agrees with the standard model prediction. Limits on the vector boson fusion production cross section times branching fraction for new charged physical states are reported as a function of mass from 200 to 2000 GeV and interpreted in the context of Higgs triplet models.

9.
Phys Rev Lett ; 119(15): 152301, 2017 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-29077459

RESUMO

The differential production cross sections of B^{±} mesons are measured via the exclusive decay channels B^{±}→J/ψK^{±}→µ^{+}µ^{-}K^{±} as a function of transverse momentum in pp and Pb-Pb collisions at a center-of-mass energy sqrt[s_{NN}]=5.02 TeV per nucleon pair with the CMS detector at the LHC. The pp(Pb-Pb) data set used for this analysis corresponds to an integrated luminosity of 28.0 pb^{-1} (351 µb^{-1}). The measurement is performed in the B^{±} meson transverse momentum range of 7 to 50 GeV/c, in the rapidity interval |y|<2.4. In this kinematic range, a strong suppression of the production cross section by about a factor of 2 is observed in the Pb-Pb system in comparison to the expectation from pp reference data. These results are found to be roughly compatible with theoretical calculations incorporating beauty quark diffusion and energy loss in a quark-gluon plasma.

10.
Phys Rev Lett ; 118(2): 021802, 2017 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-28128610

RESUMO

A first search for pair production of dark matter candidates through vector boson fusion in proton-proton collisions at sqrt[s]=8 TeV is performed with the CMS detector. The vector boson fusion topology enhances missing transverse momentum, providing a way to probe supersymmetry, even in the case of a compressed mass spectrum. The data sample corresponds to an integrated luminosity of 18.5 fb^{-1}, recorded by the CMS experiment. The observed dijet mass spectrum is consistent with the standard model expectation. In an effective field theory, dark matter masses are explored as a function of contact interaction strength. The most stringent limit on bottom squark production with mass below 315 GeV is also reported, assuming a 5 GeV mass difference with respect to the lightest neutralino.

11.
Br J Dermatol ; 176(2): 395-402, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27452897

RESUMO

BACKGROUND: Antimelanoma differentiation-associated protein (anti-MDA)5 antibodies are associated with rapidly progressive interstitial lung disease (RP-ILD) in patients with clinically amyopathic dermatomyositis (CADM) or dermatomyositis (DM). OBJECTIVES: We aimed to evaluate the relevance of monitoring anti-MDA5 antibody levels for the management of RP-ILD in patients with CADM or DM. METHODS: Twelve patients with CADM (n = 10) or DM (n = 2) accompanied by RP-ILD were included. Baseline characteristics and outcomes were recorded. Serial measurements of anti-MDA5 antibody levels were measured. All patients were treated with corticosteroids, tacrolimus and intravenous cyclophosphamide. RESULTS: All patients achieved RP-ILD remission after combined immunosuppressive therapy for a mean of 6·8 months, with significant decreases noted in the mean anti-MDA5 antibody levels at remission. Six (50%) patients became anti-MDA5 antibody negative after therapy. After a mean follow-up of 31 months, RP-ILD relapse was observed in four (33%) patients in both the anti-MDA5 antibody sustained positive group and the negative conversion group. However, relapsed patients in the sustained positive group relapsed earlier than those in the negative conversion group. Thus, a decrease in anti-MDA5 antibody levels during remission was associated with longer remission. Relapses were associated with a reincrease of anti-MDA5 antibody levels in four of four (100%) patients. In contrast, none of the patients without reincrease in anti-MDA5 antibody exhibited symptoms of relapse during follow-up. Therefore, reincrease in anti-MDA5 antibody levels was associated with relapse. CONCLUSIONS: The anti-MDA5 antibody level is a novel parameter for monitoring and a good predictor of RP-ILD relapse in patients with CADM or DM.


Assuntos
Dermatomiosite/imunologia , Doenças Pulmonares Intersticiais/imunologia , Corticosteroides/uso terapêutico , Autoanticorpos/metabolismo , Ciclofosfamida/uso terapêutico , Fármacos Dermatológicos/uso terapêutico , Dermatomiosite/tratamento farmacológico , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/uso terapêutico , Helicase IFIH1 Induzida por Interferon/imunologia , Doenças Pulmonares Intersticiais/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Recidiva , Resultado do Tratamento
12.
Haemophilia ; 23(2): 215-221, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27704637

RESUMO

BACKGROUND: Continuous infusion (CI) of recombinant FVIII (rFVIII) concentrates has been reported as an effective and safe method to achieve haemostasis during major surgeries or severe bleeding events. For more effective and safer CI, better understanding of in vivo recovery (IVR) and clearance (CL) issues is imperative. OBJECTIVE: We investigated the following factors affecting IVR and CL using univariate and multivariate regression analyses during 47 CIs in 34 patients: rFVIII concentrate type, haemophilia severity, blood type, the presence of hepatitis C virus (HCV) or human immunodeficiency virus (HIV), age and body mass index (BMI). RESULTS: The mean IVR was 1.64 ± 0.49 IU dL-1 per IU kg-1 , and the mean CL during CI was 3.56 ± 1.57 mL h-1 kg-1 . The univariate and multivariate regression analyses showed that the CL of octocog alfa was significantly lower than that of rurioctocog alfa (P = 0.043 and 0.0034, respectively). There was a significant difference in BMI in the univariate and multivariate regression analyses (P = 0.0403 and 0.0376, respectively). CONCLUSIONS: This study indicated that CL during CI was potentially affected by the type of rFVIII concentrate used and BMI.


Assuntos
Fator VIII/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Fator VIII/farmacocinética , Humanos , Bombas de Infusão , Pessoa de Meia-Idade , Proteínas Recombinantes/farmacocinética , Estudos Retrospectivos , Adulto Jovem
13.
Haemophilia ; 23(4): 547-555, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28233381

RESUMO

INTRODUCTION: Nonacog beta pegol (N9-GP) is a glycoPEGylated recombinant factor IX (FIX) with an extended half-life developed for routine prophylaxis and the prevention and treatment of bleeding episodes in patients with haemophilia B. AIM: The aim of this study was to evaluate the pharmacokinetics (PK) of N9-GP. METHODS: Data from 41 previously treated haemophilia B patients, enrolled globally (16 adolescents/adults and 25 children; FIX activity ≤0.02 IU mL-1 ) with no history of FIX inhibitors, were included. N9-GP was administered once-weekly as 10 IU kg-1 or 40 IU kg-1 in adolescents/adults and 40 IU kg-1 in children. Blood was sampled up to 168 h (1 week) post dose. Standard PK was estimated on the basis of plasma FIX activity vs. time (PK profiles) using non-compartmental methods. Furthermore, a population PK analysis and FIX activity predictions were performed. RESULTS: Incremental recoveries were 0.02 (IU mL-1 )/(IU kg-1 ) in both adolescents/adults and children. The extended half-life resulted in mean trough levels of 0.27 IU mL-1 for adolescents/adults and 0.17 IU mL-1 for children at steady-state after weekly dosing at 40 IU kg-1 . The population PK analysis confirmed a mono-exponential decay in FIX activity and allowed for predictions of FIX activity for adolescents/adults above 0.15 IU mL-1 at all times and 6.4 days week-1 in children. CONCLUSION: N9-GP has the potential to shift previously treated haemophilia B patients from a severe/moderate disease state into a mild- or non-haemophilic range for most of the dosing interval, which is expected to reduce the number of bleeding episodes.


Assuntos
Fator IX/farmacocinética , Hemofilia B/tratamento farmacológico , Hemofilia B/metabolismo , Polietilenoglicóis/farmacocinética , Adolescente , Criança , Pré-Escolar , Relação Dose-Resposta a Droga , Fator IX/uso terapêutico , Humanos , Masculino , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/uso terapêutico , Distribuição Tecidual
14.
Haemophilia ; 23(1): 59-66, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27480904

RESUMO

INTRODUCTION: MC710, a 1:10 protein weight ratio mixture of plasma-derived activated factor VII (FVIIa) and factor X (FX), is a novel bypassing agent for haemostasis in haemophilia patients with inhibitors. We evaluated the haemostatic efficacy and safety of one to two administrations of MC710 in 21 joint, muscle, and subcutaneous bleeding episodes in 14 male patients, in a multi-centre, open-label, non-randomized clinical trial. METHODS: Subjects were intravenously administered one or two doses of 60 or 120 µg kg-1 MC710 (as FVIIa) once or twice (to a maximum of 180 µg kg-1 ) over up to five bleeding episodes per subject. The haemostatic efficacy of MC710 was determined for each episode by investigator evaluation, using changes in visual analogue scale (VAS) for pain relief, and/or knee joint or muscle circumference for swelling reduction, and range of motion (ROM) for improvement of joint mobility. RESULTS: In 21 treatments for bleeding episodes, 19 were rated "excellent" or "effective" 8 h after the last treatment. VAS significantly decreased over time, and ROM significantly improved over time compared with the values before treatment. One mild adverse reaction, decreased blood potassium, and two serious adverse events, both knee joint bleeding, were observed within 1 week after first administration, with no significant effect on safety. Furthermore, diagnostic markers did not show any signs of disseminated intravascular coagulation (DIC). CONCLUSION: These results show that MC710 has sufficient haemostatic efficacy and safety, and can be used as a potential bypassing agent to control bleeding in haemophilia patients with inhibitors.


Assuntos
Fator VIIa/uso terapêutico , Fator X/uso terapêutico , Hemofilia A/tratamento farmacológico , Adolescente , Adulto , Humanos , Masculino , Adulto Jovem
15.
Phys Rev Lett ; 117(5): 051802, 2016 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-27517765

RESUMO

A search for the resonant production of high-mass photon pairs is presented. The analysis is based on samples of proton-proton collision data collected by the CMS experiment at center-of-mass energies of 8 and 13 TeV, corresponding to integrated luminosities of 19.7 and 3.3 fb^{-1}, respectively. The interpretation of the search results focuses on spin-0 and spin-2 resonances with masses between 0.5 and 4 TeV and with widths, relative to the mass, between 1.4×10^{-4} and 5.6×10^{-2}. Limits are set on scalar resonances produced through gluon-gluon fusion, and on Randall-Sundrum gravitons. A modest excess of events compatible with a narrow resonance with a mass of about 750 GeV is observed. The local significance of the excess is approximately 3.4 standard deviations. The significance is reduced to 1.6 standard deviations once the effect of searching under multiple signal hypotheses is considered. More data are required to determine the origin of this excess.

16.
Phys Rev Lett ; 116(5): 052002, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26894703

RESUMO

The top quark pair production cross section is measured for the first time in proton-proton collisions at sqrt[s]=13 TeV by the CMS experiment at the CERN LHC, using data corresponding to an integrated luminosity of 43 pb^{-1}. The measurement is performed by analyzing events with at least one electron and one muon of opposite charge, and at least two jets. The measured cross section is 746±58(stat)±53(syst)±36(lumi) pb, in agreement with the expectation from the standard model.

17.
Phys Rev Lett ; 116(7): 071801, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26943527

RESUMO

A search for narrow resonances in proton-proton collisions at sqrt[s]=13 TeV is presented. The invariant mass distribution of the two leading jets is measured with the CMS detector using a data set corresponding to an integrated luminosity of 2.4 fb^{-1}. The highest observed dijet mass is 6.1 TeV. The distribution is smooth and no evidence for resonant particles is observed. Upper limits at 95% confidence level are set on the production cross section for narrow resonances with masses above 1.5 TeV. When interpreted in the context of specific models, the limits exclude string resonances with masses below 7.0 TeV, scalar diquarks below 6.0 TeV, axigluons and colorons below 5.1 TeV, excited quarks below 5.0 TeV, color-octet scalars below 3.1 TeV, and W^{'} bosons below 2.6 TeV. These results significantly extend previously published limits.

18.
Phys Rev Lett ; 116(3): 032301, 2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26849587

RESUMO

The production cross sections of the B^{+}, B^{0}, and B_{s}^{0} mesons, and of their charge conjugates, are measured via exclusive hadronic decays in p+Pb collisions at the center-of-mass energy sqrt[s_{NN}]=5.02 TeV with the CMS detector at the CERN LHC. The data set used for this analysis corresponds to an integrated luminosity of 34.6 nb^{-1}. The production cross sections are measured in the transverse momentum range between 10 and 60 GeV/c. No significant modification is observed compared to proton-proton perturbative QCD calculations scaled by the number of incoherent nucleon-nucleon collisions. These results provide a baseline for the study of in-medium b quark energy loss in Pb+Pb collisions.

19.
Phys Rev Lett ; 116(17): 172302, 2016 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-27176516

RESUMO

Results on two-particle angular correlations for charged particles produced in pp collisions at a center-of-mass energy of 13 TeV are presented. The data were taken with the CMS detector at the LHC and correspond to an integrated luminosity of about 270 nb^{-1}. The correlations are studied over a broad range of pseudorapidity (|η|<2.4) and over the full azimuth (ϕ) as a function of charged particle multiplicity and transverse momentum (p_{T}). In high-multiplicity events, a long-range (|Δη|>2.0), near-side (Δϕ≈0) structure emerges in the two-particle Δη-Δϕ correlation functions. The magnitude of the correlation exhibits a pronounced maximum in the range 1.0

20.
Phys Rev Lett ; 117(3): 031802, 2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27472109

RESUMO

A search for narrow resonances decaying into dijet final states is performed on data from proton-proton collisions at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 18.8 fb^{-1}. The data were collected with the CMS detector using a novel technique called data scouting, in which the information associated with these selected events is much reduced, permitting collection of larger data samples. This technique enables CMS to record events containing jets at a rate of 1 kHz, by collecting the data from the high-level-trigger system. In this way, the sensitivity to low-mass resonances is increased significantly, allowing previously inaccessible couplings of new resonances to quarks and gluons to be probed. The resulting dijet mass distribution yields no evidence of narrow resonances. Upper limits are presented on the resonance cross sections as a function of mass, and compared with a variety of models predicting narrow resonances. The limits are translated into upper limits on the coupling of a leptophobic resonance Z_{B}^{'} to quarks, improving on the results obtained by previous experiments for the mass range from 500 to 800 GeV.

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