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1.
Artigo em Inglês | MEDLINE | ID: mdl-38918115

RESUMO

BACKGROUND: While Chronic Myeloid Leukemia (CML) is a disease of older adults, there is a growing population of adolescent and young adults (AYAs) with CML. This study evaluated the clinical characteristics and outcomes of CML in AYAs. PATIENTS AND METHODS: Data from medical records of adults with chronic phase CML diagnosed and treated at our center from 2011until 2021were retrospectively analyzed. Age between 18 and 29 years was used to define AYAs. Response to tyrosine kinase inhibitors (TKIs), progression to accelerated phase (AP) or blast crisis (BC), event-free survival (EFS) and overall survival (OS) were compared between AYAs and older adults. RESULTS: Among 163 patients included, 41 (25.1%) were AYAs. AYAs were more likely to be males (P = .02), to present with symptoms (P = .004), had a higher median white blood cell count (P = .007), neutrophil count (P = .029), eosinophil count (P = 0.01), low-risk Sokal (P = .033) and Hasford (P = .005) groups. TKI-sensitivity as well as median times for achievement of complete cytogenetic and major molecular response were comparable between both groups. After a median follow-up of 76 (range: 11-235) months, there was no difference in OS (P = .528), or cumulative incidence of transformation to accelerated phase or blast crisis (P = .11). On the other hand, AYA had an inferior EFS (P = .034). CONCLUSION: A quarter of the patients diagnosed with CML in our population were AYAs. Despite being characterized as "lower-risk," they presented with a greater disease burden, had a shorter EFS but comparable OS. Further studies are needed to better understand the disease biology of this group.

2.
Anal Chem ; 94(32): 11134-11143, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35920637

RESUMO

This paper describes an experimental system for simultaneous permeation of a pressurized test gas through different gas permeable membranes and provides a proof of concept for a novel approach for gas identification/fingerprinting for potential construction of electronic noses. The design, construction, and use of a six-channel system which allows simultaneous gas permeation from a single pressurized gas compartment through six different parallel membranes are presented. The permeated gas is accumulated in confined spaces behind the respective membranes. The rate of gas pressure accumulation behind each membrane is recorded and used as a measure of the gas permeation rate through the membrane. The utilized gas permeable membranes include Teflon AF, silicone rubber, track-etch hydrophilic polycarbonate, track-etch hydrophobic polycarbonate, track-etch polyimide, nanoporous anodic aluminum oxide, zeolite ZSM-5, and zeolite NaY. An analogy between the rate of pressure accumulation of the permeating gas behind the membrane and the charging of an electric capacitor in a single series RC circuit is proposed and thoroughly validated. The simultaneous permeation rates through different membranes demonstrated a very promising potential as characteristic fingerprints for 10 test gases, that is, helium, neon, argon, hydrogen, nitrogen, carbon dioxide, methane, ethane, propane, and ethylene, which are selected as representative examples of mono-, di-, tri-, and polyatomic gases and to include some homologous series as well as to allow testing the potential of the proposed system to discriminate between closely related gases such as ethane and ethylene or carbon dioxide and propane which have almost identical molecular masses. Finally, a preliminary investigation of the possibility of applying the developed gas permeation system for semiquantitative analysis of the CO2-N2 binary mixture is also presented.


Assuntos
Dióxido de Carbono , Zeolitas , Dióxido de Carbono/química , Etano , Etilenos , Hélio , Propano , Zeolitas/química
3.
Adv Exp Med Biol ; 1269: 45-49, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33966193

RESUMO

This case report describes a major surgical procedure for a protein C-deficient, hypercoagulable patient who underwent two back-to-back invasive surgeries, hip replacement, and spinal stenosis correction. The patient, an 84-year-old male with a history of deep vein thromboses (DVT) and pulmonary emboli (PE), was treated pre-, peri-, and postoperatively with zymogen protein C (ZPC-Baxter, International) and recovered without clotting or increased bleeding. During the procedure, the patient was not administered any other anticoagulants. There have now been several case reports on different patients with unrelated teams in various locations worldwide using zymogen protein C during surgical procedures. Thus, this procedure is becoming a viable choice for patients with a high probability of clotting during and after invasive surgery. This case focuses on accomplishing safer surgery and reducing costs, by using less ZPC while accomplishing two surgeries in one procedure. As a result, this procedure might be useful for many medical situations where acquired protein C deficiency could be a problem (e.g., sepsis, pregnancy, etc.). This approach may have greater application to medical conditions other than protein C deficiency, where clotting and inflammation can become issues.


Assuntos
Deficiência de Proteína C , Proteína C , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Precursores Enzimáticos , Humanos , Masculino , Segurança do Paciente
4.
Phys Rev E ; 101(5-1): 051201, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32575250

RESUMO

We discuss the experimental and modeling results for the x-ray heating and temperature of laboratory photoionized plasmas. A method is used to extract the electron temperature based on the analysis of transmission spectroscopy data that is independent of atomic kinetics modeling. The results emphasized the critical role of x-ray heating and radiation cooling in determining the energy balance of the plasma. They also demonstrated the dramatic impact of photoexcitation on excited-state populations, line emissivity, and radiation cooling. Modeling calculations performed with astrophysical codes significantly overestimated the measured temperature.

6.
Eur Phys J C Part Fields ; 78(12): 987, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30872953

RESUMO

The Tile Calorimeter is the hadron calorimeter covering the central region of the ATLAS experiment at the Large Hadron Collider. Approximately 10,000 photomultipliers collect light from scintillating tiles acting as the active material sandwiched between slabs of steel absorber. This paper gives an overview of the calorimeter's performance during the years 2008-2012 using cosmic-ray muon events and proton-proton collision data at centre-of-mass energies of 7 and 8 TeV with a total integrated luminosity of nearly 30 fb - 1 . The signal reconstruction methods, calibration systems as well as the detector operation status are presented. The energy and time calibration methods performed excellently, resulting in good stability of the calorimeter response under varying conditions during the LHC Run 1. Finally, the Tile Calorimeter response to isolated muons and hadrons as well as to jets from proton-proton collisions is presented. The results demonstrate excellent performance in accord with specifications mentioned in the Technical Design Report.

7.
Eur Phys J C Part Fields ; 78(3): 171, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31265000

RESUMO

The modification of the production of J / ψ , ψ ( 2 S ) , and Υ ( n S ) ( n = 1 , 2 , 3 ) in p+Pb collisions with respect to their production in pp collisions has been studied. The p+Pb and pp datasets used in this paper correspond to integrated luminosities of 28 nb - 1 and 25 pb - 1 respectively, collected in 2013 and 2015 by the ATLAS detector at the LHC, both at a centre-of-mass energy per nucleon pair of 5.02 TeV. The quarkonium states are reconstructed in the dimuon decay channel. The yields of J / ψ and ψ ( 2 S ) are separated into prompt and non-prompt sources. The measured quarkonium differential cross sections are presented as a function of rapidity and transverse momentum, as is the nuclear modification factor, R p Pb for J / ψ and Υ ( n S ) . No significant modification of the J / ψ production is observed while Υ ( n S ) production is found to be suppressed at low transverse momentum in p+Pb collisions relative to pp collisions. The production of excited charmonium and bottomonium states is found to be suppressed relative to that of the ground states in central p+Pb collisions.

8.
Eur Phys J C Part Fields ; 78(2): 110, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31265006

RESUMO

A measurement of the mass of the W boson is presented based on proton-proton collision data recorded in 2011 at a centre-of-mass energy of 7 TeV with the ATLAS detector at the LHC, and corresponding to 4.6 fb - 1 of integrated luminosity. The selected data sample consists of 7.8 × 10 6 candidates in the W → µ ν channel and 5.9 × 10 6 candidates in the W → e ν channel. The W-boson mass is obtained from template fits to the reconstructed distributions of the charged lepton transverse momentum and of the W boson transverse mass in the electron and muon decay channels, yielding m W = 80370 ± 7 ( stat. ) ± 11 ( exp. syst. ) ± 14 ( mod. syst. ) MeV = 80370 ± 19 MeV , where the first uncertainty is statistical, the second corresponds to the experimental systematic uncertainty, and the third to the physics-modelling systematic uncertainty. A measurement of the mass difference between the W + and W - bosons yields m W + - m W - = - 29 ± 28  MeV.

9.
Eur Phys J C Part Fields ; 77(6): 361, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29200941

RESUMO

Measurements of the production cross section of a [Formula: see text] boson in association with jets in proton-proton collisions at [Formula: see text] TeV are presented, using data corresponding to an integrated luminosity of 3.16 fb[Formula: see text] collected by the ATLAS experiment at the CERN Large Hadron Collider in 2015. Inclusive and differential cross sections are measured for events containing a [Formula: see text] boson decaying to electrons or muons and produced in association with up to seven jets with [Formula: see text] GeV and [Formula: see text]. Predictions from different Monte Carlo generators based on leading-order and next-to-leading-order matrix elements for up to two additional partons interfaced with parton shower and fixed-order predictions at next-to-leading order and next-to-next-to-leading order are compared with the measured cross sections. Good agreement within the uncertainties is observed for most of the modelled quantities, in particular with the generators which use next-to-leading-order matrix elements and the more recent next-to-next-to-leading-order fixed-order predictions.

10.
Eur Phys J C Part Fields ; 77(6): 428, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29200942

RESUMO

Multi-particle cumulants and corresponding Fourier harmonics are measured for azimuthal angle distributions of charged particles in [Formula: see text] collisions at [Formula: see text] = 5.02 and 13 TeV and in [Formula: see text] + Pb collisions at [Formula: see text] = 5.02 TeV, and compared to the results obtained for low-multiplicity [Formula: see text] collisions at [Formula: see text] = 2.76 TeV. These measurements aim to assess the collective nature of particle production. The measurements of multi-particle cumulants confirm the evidence for collective phenomena in [Formula: see text] + Pb and low-multiplicity [Formula: see text] collisions. On the other hand, the [Formula: see text] results for four-particle cumulants do not demonstrate collective behaviour, indicating that they may be biased by contributions from non-flow correlations. A comparison of multi-particle cumulants and derived Fourier harmonics across different collision systems is presented as a function of the charged-particle multiplicity. For a given multiplicity, the measured Fourier harmonics are largest in [Formula: see text], smaller in [Formula: see text] + Pb and smallest in [Formula: see text] collisions. The [Formula: see text] results show no dependence on the collision energy, nor on the multiplicity.

11.
Eur Phys J C Part Fields ; 77(10): 673, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29081711

RESUMO

With the increase in energy of the Large Hadron Collider to a centre-of-mass energy of 13 [Formula: see text] for Run 2, events with dense environments, such as in the cores of high-energy jets, became a focus for new physics searches as well as measurements of the Standard Model. These environments are characterized by charged-particle separations of the order of the tracking detectors sensor granularity. Basic track quantities are compared between 3.2 fb[Formula: see text] of data collected by the ATLAS experiment and simulation of proton-proton collisions producing high-transverse-momentum jets at a centre-of-mass energy of 13 [Formula: see text]. The impact of charged-particle separations and multiplicities on the track reconstruction performance is discussed. The track reconstruction efficiency in the cores of jets with transverse momenta between 200 and 1600 [Formula: see text] is quantified using a novel, data-driven, method. The method uses the energy loss, [Formula: see text], to identify pixel clusters originating from two charged particles. Of the charged particles creating these clusters, the measured fraction that fail to be reconstructed is [Formula: see text] and [Formula: see text] for jet transverse momenta of 200-400 [Formula: see text] and 1400-1600 [Formula: see text], respectively.

12.
Eur Phys J C Part Fields ; 77(5): 317, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28943784

RESUMO

During 2015 the ATLAS experiment recorded [Formula: see text] of proton-proton collision data at a centre-of-mass energy of [Formula: see text]. The ATLAS trigger system is a crucial component of the experiment, responsible for selecting events of interest at a recording rate of approximately 1 kHz from up to 40 MHz of collisions. This paper presents a short overview of the changes to the trigger and data acquisition systems during the first long shutdown of the LHC and shows the performance of the trigger system and its components based on the 2015 proton-proton collision data.

13.
Eur Phys J C Part Fields ; 77(5): 332, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28943786

RESUMO

This paper presents the method and performance of primary vertex reconstruction in proton-proton collision data recorded by the ATLAS experiment during Run 1 of the LHC. The studies presented focus on data taken during 2012 at a centre-of-mass energy of [Formula: see text] TeV. The performance has been measured as a function of the number of interactions per bunch crossing over a wide range, from one to seventy. The measurement of the position and size of the luminous region and its use as a constraint to improve the primary vertex resolution are discussed. A longitudinal vertex position resolution of about [Formula: see text] is achieved for events with high multiplicity of reconstructed tracks. The transverse position resolution is better than [Formula: see text] and is dominated by the precision on the size of the luminous region. An analytical model is proposed to describe the primary vertex reconstruction efficiency as a function of the number of interactions per bunch crossing and of the longitudinal size of the luminous region. Agreement between the data and the predictions of this model is better than 3% up to seventy interactions per bunch crossing.

14.
Eur Phys J C Part Fields ; 77(7): 466, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28943792

RESUMO

This paper describes the implementation and performance of a particle flow algorithm applied to 20.2 fb[Formula: see text] of ATLAS data from 8 TeV proton-proton collisions in Run 1 of the LHC. The algorithm removes calorimeter energy deposits due to charged hadrons from consideration during jet reconstruction, instead using measurements of their momenta from the inner tracker. This improves the accuracy of the charged-hadron measurement, while retaining the calorimeter measurements of neutral-particle energies. The paper places emphasis on how this is achieved, while minimising double-counting of charged-hadron signals between the inner tracker and calorimeter. The performance of particle flow jets, formed from the ensemble of signals from the calorimeter and the inner tracker, is compared to that of jets reconstructed from calorimeter energy deposits alone, demonstrating improvements in resolution and pile-up stability.

15.
Eur Phys J C Part Fields ; 77(7): 474, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28943794

RESUMO

Measurements of the electroweak production of a W boson in association with two jets at high dijet invariant mass are performed using [Formula: see text] 7 and 8 [Formula: see text] proton-proton collision data produced by the Large Hadron Collider, corresponding respectively to 4.7 and 20.2 fb[Formula: see text] of integrated luminosity collected by the ATLAS detector. The measurements are sensitive to the production of a W boson via a triple-gauge-boson vertex and include both the fiducial and differential cross sections of the electroweak process.

16.
Eur Phys J C Part Fields ; 77(8): 531, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28943801

RESUMO

Detailed measurements of t-channel single top-quark production are presented. They use 20.2 fb[Formula: see text] of data collected by the ATLAS experiment in proton-proton collisions at a centre-of-mass energy of 8 TeV at the LHC. Total, fiducial and differential cross-sections are measured for both top-quark and top-antiquark production. The fiducial cross-section is measured with a precision of 5.8% (top quark) and 7.8% (top antiquark), respectively. The total cross-sections are measured to be [Formula: see text] for top-quark production and [Formula: see text] for top-antiquark production, in agreement with the Standard Model prediction. In addition, the ratio of top-quark to top-antiquark production cross-sections is determined to be [Formula: see text]. The differential cross-sections as a function of the transverse momentum and rapidity of both the top quark and the top antiquark are measured at both the parton and particle levels. The transverse momentum and rapidity differential cross-sections of the accompanying jet from the t-channel scattering are measured at particle level. All measurements are compared to various Monte Carlo predictions as well as to fixed-order QCD calculations where available.

17.
Eur Phys J C Part Fields ; 77(7): 490, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28943797

RESUMO

The reconstruction of the signal from hadrons and jets emerging from the proton-proton collisions at the Large Hadron Collider (LHC) and entering the ATLAS calorimeters is based on a three-dimensional topological clustering of individual calorimeter cell signals. The cluster formation follows cell signal-significance patterns generated by electromagnetic and hadronic showers. In this, the clustering algorithm implicitly performs a topological noise suppression by removing cells with insignificant signals which are not in close proximity to cells with significant signals. The resulting topological cell clusters have shape and location information, which is exploited to apply a local energy calibration and corrections depending on the nature of the cluster. Topological cell clustering is established as a well-performing calorimeter signal definition for jet and missing transverse momentum reconstruction in ATLAS.

18.
Eur Phys J C Part Fields ; 77(2): 70, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28775664

RESUMO

Direct searches for lepton flavour violation in decays of the Higgs and Z bosons with the ATLAS detector at the LHC are presented. The following three decays are considered: [Formula: see text], [Formula: see text], and [Formula: see text]. The searches are based on the data sample of proton-proton collisions collected by the ATLAS detector corresponding to an integrated luminosity of 20.3 [Formula: see text] at a centre-of-mass energy of [Formula: see text] TeV. No significant excess is observed, and upper limits on the lepton-flavour-violating branching ratios are set at the 95[Formula: see text] confidence level: Br[Formula: see text], Br[Formula: see text], and Br[Formula: see text].

19.
Eur Phys J C Part Fields ; 77(6): 393, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28781578

RESUMO

Results of a search for physics beyond the Standard Model in events containing an energetic photon and large missing transverse momentum with the ATLAS detector at the Large Hadron Collider are reported. As the number of events observed in data, corresponding to an integrated luminosity of 36.1 fb[Formula: see text]  of proton-proton collisions at a centre-of-mass energy of [Formula: see text], is in agreement with the Standard Model expectations, model-independent limits are set on the fiducial cross section for the production of events in this final state. Exclusion limits are also placed in models where dark-matter candidates are pair-produced. For dark-matter production via an axial-vector or a vector mediator in the s-channel, this search excludes mediator masses below 750-[Formula: see text] for dark-matter candidate masses below 230-[Formula: see text] at 95% confidence level, depending on the couplings. In an effective theory of dark-matter production, the limits restrict the value of the suppression scale [Formula: see text] to be above [Formula: see text] at 95% confidence level. A limit is also reported on the production of a high-mass scalar resonance by processes beyond the Standard Model, in which the resonance decays to [Formula: see text] and the Z boson subsequently decays into neutrinos.

20.
Eur Phys J C Part Fields ; 77(3): 144, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28690423

RESUMO

Two searches for new phenomena in final states containing a same-flavour opposite-sign lepton (electron or muon) pair, jets, and large missing transverse momentum are presented. These searches make use of proton-proton collision data, collected during 2015 and 2016 at a centre-of-mass energy [Formula: see text] [Formula: see text] by the ATLAS detector at the large hadron collider, which correspond to an integrated luminosity of [Formula: see text]. Both searches target the pair production of supersymmetric particles, squarks or gluinos, which decay to final states containing a same-flavour opposite-sign lepton pair via one of two mechanisms: a leptonically decaying Z boson in the final state, leading to a peak in the dilepton invariant-mass distribution around the Z boson mass; and decays of neutralinos (e.g. [Formula: see text]), yielding a kinematic endpoint in the dilepton invariant-mass spectrum. The data are found to be consistent with the Standard Model expectation. Results are interpreted in simplified models of gluino-pair (squark-pair) production, and provide sensitivity to gluinos (squarks) with masses as large as 1.70 [Formula: see text] (980 [Formula: see text]).

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