63 research outputs found
Multiplicity dependence of jet-like two-particle correlations in p-Pb collisions at = 5.02 TeV
Two-particle angular correlations between unidentified charged trigger and
associated particles are measured by the ALICE detector in p-Pb collisions at a
nucleon-nucleon centre-of-mass energy of 5.02 TeV. The transverse-momentum
range 0.7 5.0 GeV/ is examined,
to include correlations induced by jets originating from low
momen\-tum-transfer scatterings (minijets). The correlations expressed as
associated yield per trigger particle are obtained in the pseudorapidity range
. The near-side long-range pseudorapidity correlations observed in
high-multiplicity p-Pb collisions are subtracted from both near-side
short-range and away-side correlations in order to remove the non-jet-like
components. The yields in the jet-like peaks are found to be invariant with
event multiplicity with the exception of events with low multiplicity. This
invariance is consistent with the particles being produced via the incoherent
fragmentation of multiple parton--parton scatterings, while the yield related
to the previously observed ridge structures is not jet-related. The number of
uncorrelated sources of particle production is found to increase linearly with
multiplicity, suggesting no saturation of the number of multi-parton
interactions even in the highest multiplicity p-Pb collisions. Further, the
number scales in the intermediate multiplicity region with the number of binary
nucleon-nucleon collisions estimated with a Glauber Monte-Carlo simulation.Comment: 23 pages, 6 captioned figures, 1 table, authors from page 17,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/161
Multi-particle azimuthal correlations in p-Pb and Pb-Pb collisions at the CERN Large Hadron Collider
Measurements of multi-particle azimuthal correlations (cumulants) for charged
particles in p-Pb and Pb-Pb collisions are presented. They help address the
question of whether there is evidence for global, flow-like, azimuthal
correlations in the p-Pb system. Comparisons are made to measurements from the
larger Pb-Pb system, where such evidence is established. In particular, the
second harmonic two-particle cumulants are found to decrease with multiplicity,
characteristic of a dominance of few-particle correlations in p-Pb collisions.
However, when a gap is placed to suppress such correlations,
the two-particle cumulants begin to rise at high-multiplicity, indicating the
presence of global azimuthal correlations. The Pb-Pb values are higher than the
p-Pb values at similar multiplicities. In both systems, the second harmonic
four-particle cumulants exhibit a transition from positive to negative values
when the multiplicity increases. The negative values allow for a measurement of
to be made, which is found to be higher in Pb-Pb collisions at
similar multiplicities. The second harmonic six-particle cumulants are also
found to be higher in Pb-Pb collisions. In Pb-Pb collisions, we generally find
which is indicative of a Bessel-Gaussian
function for the distribution. For very high-multiplicity Pb-Pb
collisions, we observe that the four- and six-particle cumulants become
consistent with 0. Finally, third harmonic two-particle cumulants in p-Pb and
Pb-Pb are measured. These are found to be similar for overlapping
multiplicities, when a gap is placed.Comment: 25 pages, 11 captioned figures, 3 tables, authors from page 20,
published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/87
Charged jet cross sections and properties in proton-proton collisions at root s=7 TeV
The differential charged jet cross sections, jet fragmentation distributions, and jet shapes are measured in minimum bias proton-proton collisions at center-of-mass energy root s = 7 TeV using the ALICE detector at the LHC. Jets are reconstructed from charged particle momenta in the midrapidity region using the sequential recombination k(T) and anti-k(T) as well as the SISCone jet finding algorithms with several resolution parameters in the range R = 0.2-0.6. Differential jet production cross sections measured with the three jet finders are in agreement in the transverse momentum (p(T)) interval 20 ) of the reconstructed jet p(T). The fragmentation of leading jets with R = 0.4 using scaled p(T) spectra of the jet constituents is studied. The measurements are compared to model calculations from event generators (PYTHIA, PHOJET, HERWIG). The measured radial density distributions and distributions are well described by the PYTHIA model (tune Perugia-2011). The fragmentation distributions are better described by HERWIG.Peer reviewe
Inclusive photon production at forward rapidities in proton\u2013proton collisions at 1a s = 0.9, 2.76 and 7 TeV
The multiplicity and pseudorapidity distribu- tions of inclusive photons have been measured at forward rapidities (2.3 < \u3b7 < 3.9) in proton\u2013proton collisions at three center-of-mass energies, 1as = 0.9, 2.76 and 7 TeV using the ALICE detector. It is observed that the increase in the average photon multiplicity as a function of beam energy is compatible with both a logarithmic and a power-law dependence. The relative increase in average photon multi- plicity produced in inelastic pp collisions at 2.76 and 7 TeV center-of-mass energies with respect to 0.9 TeV are 37.2 \ub1 0.3% (stat) \ub1 8.8% (sys) and 61.2 \ub1 0.3% (stat) \ub1 7.6% (sys), respectively. The photon multiplicity distributions for all center-of-mass energies are well described by negative binomial distributions. The multiplicity distributions are also presented in terms of KNO variables. The results are com- pared to model predictions, which are found in general to underestimate the data at large photon multiplicities, in par- ticular at the highest center-of-mass energy. Limiting frag- mentation behavior of photons has been explored with the data, but is not observed in the measured pseudorapidity range
Production of ÎŁ(1385)± and Î(1530)0 in protonâproton collisions at âs = 7 TeV
The production of the strange and double-strange baryon resonances (ÎŁ(1385)±, Î(1530)0) has been measured at mid-rapidity (|y| <0.5) in protonâproton collisions at sâ = 7 TeV with the ALICE detector at the LHC. Transverse momentum spectra for inelastic collisions are compared to QCD-inspired models, which in general underpredict the data. A search for the Ï(1860) pentaquark, decaying in the ÎÏ channel, has been carried out but no evidence is seen
A case report of extramedullary plasmocytomaârare pathology in the larynx
Key Clinical Message Extramedullary plasmocytoma is a rare finding. The diagnosis is made by histological and immunohistochemical examination. Hematological evaluation is mandatory to rule out multiple myeloma. Radiotherapy is treatment of choice with good results
Outcome of combined modality treatment in first-line for stage I(E) peripheral T-cell lymphoma; a nationwide population-based cohort study from the Netherlands
Peripheral T-cell lymphomas (PTCL) comprise a heterogeneous group of mature T-cell neoplasms with an unfavorable prognosis; presentation with stage I(E) disease is uncommon. In clinical practice, an abbreviated chemotherapy treatment regimen combined with radiotherapy (combined modality treatment (CMT)) is commonly used, although evidence from clinical trials is lacking. The aim of this nationwide population-based cohort study is to describe first-line treatment and outcome of patients with stage I(E) PTCL. All newly diagnosed patients â„ 18 years with stage I(E) anaplastic large cell lymphoma (ALCL), angioimmunoblastic T-cell lymphoma (AITL) and peripheral T-cell lymphoma NOS (PTCL NOS) in 1989-2020 were identified in the Netherlands Cancer Registry. Patients were categorized according to treatment regimen, i.e. chemotherapy (CT), radiotherapy (RT), CMT, other therapy and no treatment. The primary endpoint was overall survival (OS). Patients with stage I(E) ALCL, AITL and PTCL NOS (n=576) were most commonly treated with CMT (28%) or CT (29%), 2% underwent SCT. RT only was given in 18%, and 8% received other therapy and 16% no treatment. Overall, the 5-year OS was 59%. According to subtype, 5-year OS was superior for ALCL as compared to PTCL NOS and AITL (68% vs. 55% and 52%, respectively; p=0.03). For patients treated with CMT, 5-year OS was significantly higher (72%) as compared to patients treated with either CT or RT alone (55% and 55%, respectively; p.</p
Impact of etoposide and ASCT on survival among patients aged <65 years with stage II to IV PTCL: a population-based cohort study
Patients aged <65 years with peripheral T-cell lymphoma (PTCL) are treated with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP). Although the addition of etoposide (CHOEP) and consolidation with autologous stem cell transplantation (ASCT) are preferred in some countries, randomized trials are lacking. This nationwide population-based study assessed the impact of etoposide and ASCT on overall survival (OS) among patients aged 18 to 64 years with stage II to IV anaplastic large-cell lymphoma (ALCL), angioimmunoblastic T-cell lymphoma (AITL), or PTCL not otherwise specified (NOS) diagnosed between 1989 and 2018 using the Netherlands Cancer Registry. Patients were categorized into 2 calendar periods, representing pre- and post-eras of etoposide and ASCT, respectively. A total of 1427 patients were identified (ALCL, 35%; AITL, 21%; and PTCL NOS, 44%). OS increased from 39% in the period from 1989 to 2009 to 49% in the period of 2009 to 2018 (P < .01). Five-year OS was superior for patients treated with CHOEP vs CHOP (64% and 44%, respectively; P < .01). When adjusted for subtype, International Prognostic Index score, and ASCT, the risk of mortality was similar between the 2 groups, except for patients with ALK+ ALCL, for whom the risk of mortality was 6.3 times higher when treated with CHOP vs CHOEP. Patients undergoing consolidation with ASCT had superior 5-year OS of 81% compared with 39% for patients not undergoing ASCT (P < .01), regardless of whether complete remission was achieved. In patients aged <65 years with advanced-stage ALKâ ALCL, AITL, or PTCL, the use of ASCT consolidation, but not the addition of etoposide, was associated with improved OS
R-CODOX-M/R-IVAC versus DA-EPOCH-R in patients with newly diagnosed Burkitt lymphoma (HOVON/SAKK):final results of a multicentre, phase 3, open-label, randomised trial
Background: Patients with newly diagnosed high-risk Burkitt lymphoma are treated with high-intensity immune-chemotherapy regimens such as R-CODOX-M/R-IVAC or with lower-intensity regimens such as DA-EPOCH-R. The aim of this study was to make a formal comparison between these regimens. Methods: This multicentre, phase 3, open-label, randomised study was done in 26 clinical centres in the Netherlands, Belgium, and Switzerland. Eligible patients were aged 18â75 years with newly diagnosed high-risk Burkitt lymphoma without CNS involvement. Patients were randomly assigned to two cycles of R-CODOX-M/R-IVAC (R-CODOX-M: rituximab 375 mg/m2 on day 1 and 9, cyclophosphamide 800 mg/m2 on day 1, cyclophosphamide 200 mg/m2 on days 2â5, vincristine 1·5 mg/m2 on days 1 and 8, doxorubicin 40 mg/m2 on day 1, and methotrexate 3000 mg/m2 on day 10; R-IVAC: rituximab 375 mg/m2 on days 3 and 7, iphosphamide 1500 mg/m2 on days 1â5, etoposide 60 mg/m2 on days 1â5, and cytarabin 2000 mg/m2 on day 1 and 2) or six cycles of DA-EPOCH-R (dose-adjusted etoposide 50â124 mg/m2 on days 1â4, prednisolone 120 mg/m2 on days 1â5, vincristine 0·4 mg/m2 on days 1â4, dose-adjusted cyclophosphamide 480â1866 mg/m2 on day 5, dose-adjusted doxorubicin 10â24·8 mg/m2 on days 1â4, rituximab 375 mg/m2 on days 1 and 5). Patients older than 65 years received a dose modified R-CODOX-M/R-IVAC. All drugs were intravenous except for prednisolone, which was oral. Patients also received four intrathecal CNS administrations with cytarabin (70 mg) and four with methotrexate (15 mg). Patients were stratified by centre, leukemic disease, and HIV-positivity. The primary endpoint was progression-fee survival. All analyses were done by modified intention-to-treat, excluding randomly assigned patients who were subsequently found to have CNS involvement or diagnosis other than Burkitt lymphoma at study entry. This study is registered with the European Clinical Trial Register, EudraCT2013-004394-27. Findings: Due to a slow accrual, the study was closed prematurely on Nov 15, 2021. Between Aug 4, 2014, and Sept 17, 2021, 89 patients were enrolled and randomly assigned to receive R-CODOX-M/R-IVAC (n=46) or DA-EPOCH-R (n=43). Five patients were excluded after random assignment (three in the R-CODOX-M/R-IVAC group [one diagnosis other than Burkitt lymphoma at study entry according to local pathology and two CNS involvement] and two in the DA-EPOCH-R group [one diagnosis other than Burkitt lymphoma at study entry according to local pathology and one CNS involvement]. 84 remaining patients were included in the modified intention-to-treat analysis. 73 (87%) of 84 patients were male, 76 (90%) presented with stage III or IV disease, and nine (11%) had HIV-positive Burkitt lymphoma. Median patient age was 52 years (IQR 37â64). With a median follow-up of 28·5 months (IQR 13·2â43·7), 2-year progression-free survival was 76% (95% CI 60â86%) in the R-CODOX-M/R-IVAC group and 70% (54â82%) in the DA-EPOCH-R group (hazard ratio 1·42, 95% CI 0·63â3·18; p=0·40). There were two deaths in the R-CODOX-M/R-IVAC group (one infection [treatment related] and one due to disease progression [not treatment related]) and one death in the DA-EPOCH-R group (COVID-19 infection [treatment related]). In the R-CODOX-M/R-IVAC group, four patients went off-protocol because of toxic effects, versus none in the DA-EPOCH-R group. Patients treated with R-CODOX-M/R-IVAC had more infectious adverse events (24 [56%] of 43 patients had at least one grade 3â5 infection vs 14 [34%] of 41 patients in the DA-EPOCH-R group). Interpretation: The trial stopped early, but the available data suggest that while DA-EPOCH-R did not result in superior progression-free survival compared with R-CODOX-M/R-IVAC, it was associated with fewer toxic effects and need for supportive care. DA-EPOCH-R appears to be an additional valid therapeutic option for patients with high-risk Burkitt lymphoma without CNS involvement. Funding: The Dutch Cancer Society and the Schumacher-Kramer Foundation.</p
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