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1.
Phys Rev Lett ; 132(4): 042301, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38335364

RESUMO

The production of the ψ(2S) charmonium state was measured with ALICE in Pb-Pb collisions at sqrt[s_{NN}]=5.02 TeV, in the dimuon decay channel. A significant signal was observed for the first time at LHC energies down to zero transverse momentum, at forward rapidity (2.5

2.
Phys Rev Lett ; 131(4): 042303, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37566833

RESUMO

We study the polarization of inclusive J/ψ produced in Pb-Pb collisions at sqrt[s_{NN}]=5.02 TeV at the LHC in the dimuon channel, via the measurement of the angular distribution of its decay products. We perform the study in the rapidity region 2.5

3.
Phys Rev Lett ; 131(4): 042301, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37566840

RESUMO

The transverse-momentum (p_{T}) spectra and coalescence parameters B_{2} of (anti)deuterons are measured in p-p collisions at sqrt[s]=13 TeV for the first time in and out of jets. In this measurement, the direction of the leading particle with the highest p_{T} in the event (p_{T}^{lead}>5 GeV/c) is used as an approximation for the jet axis. The event is consequently divided into three azimuthal regions, and the jet signal is obtained as the difference between the toward region, that contains jet fragmentation products in addition to the underlying event (UE), and the transverse region, which is dominated by the UE. The coalescence parameter in the jet is found to be approximately a factor of 10 larger than that in the underlying event. This experimental observation is consistent with the coalescence picture and can be attributed to the smaller average phase-space distance between nucleons in the jet cone as compared with the underlying event. The results presented in this Letter are compared to predictions from a simple nucleon coalescence model, where the phase-space distributions of nucleons are generated using pythia8 with the Monash 2013 tuning, and to predictions from a deuteron production model based on ordinary nuclear reactions with parametrized energy-dependent cross sections tuned on data. The latter model is implemented in pythia8.3. Both models reproduce the observed large difference between in-jet and out-of-jet coalescence parameters, although the almost flat trend of the B_{2}^{Jet} is not reproduced by the models, which instead give a decreasing trend.

4.
Phys Rev Lett ; 131(4): 041901, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37566856

RESUMO

The first measurement of event-by-event antideuteron number fluctuations in high energy heavy-ion collisions is presented. The measurements are carried out at midrapidity (|η|<0.8) as a function of collision centrality in Pb-Pb collisions at sqrt[s_{NN}]=5.02 TeV using the ALICE detector. A significant negative correlation between the produced antiprotons and antideuterons is observed in all collision centralities. The results are compared with a state-of-the-art coalescence calculation. While it describes the ratio of higher order cumulants of the antideuteron multiplicity distribution, it fails to describe quantitatively the magnitude of the correlation between antiproton and antideuteron production. On the other hand, thermal-statistical model calculations describe all the measured observables within uncertainties only for correlation volumes that are different with respect to those describing proton yields and a similar measurement of net-proton number fluctuations.

5.
Transplant Proc ; 42(2): 461-4, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20304165

RESUMO

To study whether treatment with 5'-adenosine triphosphate (ATP), an agonist of P2 purine receptors, attenuated intestinal dysfunction caused by ischemia (I) and/or reperfusion (R), rabbits were treated with ATP (15 mgxkg(-1), intravenously) or saline solution (SS) 60 minutes before I by occlusion of the superior mesenteric artery and/or R (120 minutes). After I or I/R isolated 2-cm jejunal segments were mounted in an organ bath to study nerve-mediated contractions stimulated by electrical pulses or KCl using a digital recording system. Thin jejunal slices were stained (hematoxylin and eosin) for optical microscopy. Compared to a sham group, the jejunal contractions were similar to sham hosts among I + ATP, but reduced in I + SS, I/R + SS, and I/R + ATP groups. The jejunal-enteric nerves were damaged in I + SS, I/R + SS, and I/R + ATP, but not the I + ATP group. These results suggested that ATP attenuated intestinal dysfunction produced by I, but not that caused by R.


Assuntos
Trifosfato de Adenosina/farmacologia , Intestinos/irrigação sanguínea , Isquemia/fisiopatologia , Jejuno/irrigação sanguínea , Traumatismo por Reperfusão/fisiopatologia , Animais , Circulação Sanguínea/efeitos dos fármacos , Circulação Sanguínea/fisiologia , Isquemia/tratamento farmacológico , Jejuno/efeitos dos fármacos , Jejuno/inervação , Masculino , Artéria Mesentérica Superior/efeitos dos fármacos , Artéria Mesentérica Superior/fisiopatologia , Coelhos , Cloreto de Sódio/farmacologia
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