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1.
Dev Dyn ; 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38169311

RESUMEN

BACKGROUND: Changes in epithelial cell shape reflects optimal cell packing and the minimization of surface free energy, but also cell-cell interactions, cell proliferation, and cytoskeletal rearrangements. RESULTS: Here, we studied the structure of the rat pleura in the first 15 days after birth. After pleural isolation and image segmentation, the analysis demonstrated a progression of epithelial order from postnatal day 1 (P1) to P15. The cells with the largest surface area and greatest shape variability were observed at P1. In contrast, the cells with the smallest surface area and most shape consistency were observed at P15. A comparison of polygonal cell geometries demonstrated progressive optimization with an increase in the number of hexagons (six-sided) as well as five-sided and seven-sided polygons. Analysis of the epithelial organization with Voronoi tessellations and graphlet motif frequencies demonstrated a developmental path strikingly distinct from mathematical and natural reference paths. Graph Theory analysis of cell connectivity demonstrated a progressive decrease in network heterogeneity and clustering coefficient from P1 to P15. CONCLUSIONS: We conclude that the rat pleura undergoes a striking change in pleural structure from P1 to P15. Further, a geometric and network-based approach can provide a quantitative characterization of these developmental changes.

2.
Ann Surg ; 279(4): 577-582, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37870249

RESUMEN

OBJECTIVE: We analyze the ethics of sham surgical trials from a utilitarian perspective and explore whether patients can benefit from participating in these trials. BACKGROUND: Sham-controlled randomized trials are an essential tool to evaluate the risks and benefits of some surgical procedures. However, sham trials are controversial because they expose patients to the harms of a sham procedure without the possibility of benefit. We argue that ethical analyses of sham trials have focused only on the harms of sham surgery and neglected to account for the harms of the procedure being studied. METHODS: We develop a theoretical model to estimate the harms and benefits experienced by patients who enter a sham surgery trial, taking into account the harms and benefits of the sham and intervention. RESULTS: When the procedure in question is found to be ineffective, sham trials typically result in a net benefit to participants because some participants are only exposed to the harms of the sham procedure, which are much lower than the harms of the full procedure. When the procedure is found to be beneficial, the primary harm to patients who underwent the sham is not due to the sham itself but because they suffer a delay in receiving an effective intervention. CONCLUSIONS: Patients often benefit from participating in sham surgery trials because the harms of the sham procedure are lower than the harms of the full procedure, which may turn out to be ineffective. Our results call for re-thinking the ethics of sham surgery trials.

3.
Magn Reson Med ; 92(2): 586-604, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38688875

RESUMEN

PURPOSE: Abdominal imaging is frequently performed with breath holds or respiratory triggering to reduce the effects of respiratory motion. Diffusion weighted sequences provide a useful clinical contrast but have prolonged scan times due to low signal-to-noise ratio (SNR), and cannot be completed in a single breath hold. Echo-planar imaging (EPI) is the most commonly used trajectory for diffusion weighted imaging but it is susceptible to off-resonance artifacts. A respiratory resolved, three-dimensional (3D) diffusion prepared sequence that obtains distortionless diffusion weighted images during free-breathing is presented. Techniques to address the myriad of challenges including: 3D shot-to-shot phase correction, respiratory binning, diffusion encoding during free-breathing, and robustness to off-resonance are described. METHODS: A twice-refocused, M1-nulled diffusion preparation was combined with an RF-spoiled gradient echo readout and respiratory resolved reconstruction to obtain free-breathing diffusion weighted images in the abdomen. Cartesian sampling permits a sampling density that enables 3D shot-to-shot phase navigation and reduction of transient fat artifacts. Theoretical properties of a region-based shot rejection are described. The region-based shot rejection method was evaluated with free-breathing (normal and exaggerated breathing), and respiratory triggering. The proposed sequence was compared in vivo with multishot DW-EPI. RESULTS: The proposed sequence exhibits no evident distortion in vivo when compared to multishot DW-EPI, robustness to B0 and B1 field inhomogeneities, and robustness to motion from different respiratory patterns. CONCLUSION: Acquisition of distortionless, diffusion weighted images is feasible during free-breathing with a b-value of 500 s/mm2, scan time of 6 min, and a clinically viable reconstruction time.


Asunto(s)
Abdomen , Artefactos , Imagen de Difusión por Resonancia Magnética , Imagenología Tridimensional , Humanos , Imagen de Difusión por Resonancia Magnética/métodos , Abdomen/diagnóstico por imagen , Imagenología Tridimensional/métodos , Respiración , Algoritmos , Relación Señal-Ruido , Reproducibilidad de los Resultados , Interpretación de Imagen Asistida por Computador/métodos
4.
Phys Rev Lett ; 132(22): 222303, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38877919

RESUMEN

K^{+}K^{-} pairs may be produced in photonuclear collisions, either from the decays of photoproduced ϕ(1020) mesons or directly as nonresonant K^{+}K^{-} pairs. Measurements of K^{+}K^{-} photoproduction probe the couplings between the ϕ(1020) and charged kaons with photons and nuclear targets. The kaon-proton scattering occurs at energies far above those available elsewhere. We present the first measurement of coherent photoproduction of K^{+}K^{-} pairs on lead ions in ultraperipheral collisions using the ALICE detector, including the first investigation of direct K^{+}K^{-} production. There is significant K^{+}K^{-} production at low transverse momentum, consistent with coherent photoproduction on lead targets. In the mass range 1.1

5.
Phys Rev Lett ; 132(17): 172302, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38728735

RESUMEN

This Letter presents the measurement of near-side associated per-trigger yields, denoted ridge yields, from the analysis of angular correlations of charged hadrons in proton-proton collisions at sqrt[s]=13 TeV. Long-range ridge yields are extracted for pairs of charged particles with a pseudorapidity difference of 1.4<|Δη|<1.8 and a transverse momentum of 1

6.
Phys Rev Lett ; 132(16): 162302, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38701458

RESUMEN

The first measurement of the cross section for incoherent photonuclear production of J/ψ vector mesons as a function of the Mandelstam |t| variable is presented. The measurement was carried out with the ALICE detector at midrapidity, |y|<0.8, using ultraperipheral collisions of Pb nuclei at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=5.02 TeV. This rapidity interval corresponds to a Bjorken-x range (0.3-1.4)×10^{-3}. Cross sections are given in five |t| intervals in the range 0.04<|t|<1 GeV^{2} and compared to the predictions by different models. Models that ignore quantum fluctuations of the gluon density in the colliding hadron predict a |t| dependence of the cross section much steeper than in data. The inclusion of such fluctuations in the same models provides a better description of the data.

7.
Phys Rev Lett ; 132(4): 042301, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38335364

RESUMEN

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

8.
AJR Am J Roentgenol ; 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38170833

RESUMEN

Quantitative MRI and ultrasound biomarkers of liver fibrosis have become important tools in the diagnosis and clinical management of children with chronic liver disease (CLD). In particular, MR elastography (MRE) is now routinely performed in clinical practice to evaluate the liver for fibrosis. Ultrasound shear-wave elastography has also become widely performed for this purpose, especially in young children. These noninvasive methods are increasingly used to replace liver biopsy for the diagnosis, quantitative staging, and treatment monitoring of patients with CLD. Although ultrasound has advantages of portability and lower equipment cost, available evidence indicates that MRI may have greater reliability and accuracy in liver fibrosis evaluation. In this AJR Expert Panel Narrative Review, we describe how, why, and when to use MRI- and ultrasound-based elastography methods for liver fibrosis assessment in children. Practical approaches are discussed for adapting and optimizing these methods in children, with consideration of clinical indications, patient preparation, equipment requirements, acquisition technique, as well as pitfalls and confounding factors. Guidance is provided for interpretation and reporting, and representative case examples are presented.

9.
Pediatr Crit Care Med ; 25(7 Suppl 1): e66-e77, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38959361

RESUMEN

OBJECTIVES: To derive systematic-review informed, modified Delphi consensus regarding the management of bleeding and thrombotic complications during pediatric extracorporeal membrane oxygenation (ECMO) for the Pediatric ECMO Anticoagulation CollaborativE Consensus Conference. DATA SOURCES: A structured literature search was performed using PubMed, EMBASE, and Cochrane Library (CENTRAL) databases from January 1988 to May 2021. STUDY SELECTION: The management of bleeding and thrombotic complications of ECMO. DATA EXTRACTION: Two authors reviewed all citations independently, with a third independent reviewer resolving conflicts. Twelve references were used for data extraction and informed recommendations. Evidence tables were constructed using a standardized data extraction form. DATA SYNTHESIS: Risk of bias was assessed using the Quality in Prognosis Studies tool. The evidence was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation system. Forty-eight experts met over 2 years to develop evidence-based recommendations and, when evidence was lacking, expert-based consensus statements for the management of bleeding and thrombotic complications in pediatric ECMO patients. A web-based modified Delphi process was used to build consensus via the Research And Development/University of California Appropriateness Method. Consensus was defined as greater than 80% agreement. Two good practice statements, 5 weak recommendations, and 18 consensus statements are presented. CONCLUSIONS: Although bleeding and thrombotic complications during pediatric ECMO remain common, limited definitive data exist to support an evidence-based approach to treating these complications. Research is needed to improve hemostatic management of children supported with ECMO.


Asunto(s)
Anticoagulantes , Técnica Delphi , Oxigenación por Membrana Extracorpórea , Hemorragia , Trombosis , Oxigenación por Membrana Extracorpórea/efectos adversos , Oxigenación por Membrana Extracorpórea/métodos , Humanos , Trombosis/etiología , Trombosis/prevención & control , Hemorragia/terapia , Hemorragia/etiología , Niño , Anticoagulantes/efectos adversos , Anticoagulantes/uso terapéutico , Consenso
10.
Pediatr Crit Care Med ; 25(7): 643-675, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38959353

RESUMEN

OBJECTIVES: To present recommendations and consensus statements with supporting literature for the clinical management of neonates and children supported with extracorporeal membrane oxygenation (ECMO) from the Pediatric ECMO Anticoagulation CollaborativE (PEACE) consensus conference. DATA SOURCES: Systematic review was performed using PubMed, Embase, and Cochrane Library (CENTRAL) databases from January 1988 to May 2021, followed by serial meetings of international, interprofessional experts in the management ECMO for critically ill children. STUDY SELECTION: The management of ECMO anticoagulation for critically ill children. DATA EXTRACTION: Within each of eight subgroup, two authors reviewed all citations independently, with a third independent reviewer resolving any conflicts. DATA SYNTHESIS: A systematic review was conducted using MEDLINE, Embase, and Cochrane Library databases, from January 1988 to May 2021. Each panel developed evidence-based and, when evidence was insufficient, expert-based statements for the clinical management of anticoagulation for children supported with ECMO. These statements were reviewed and ratified by 48 PEACE experts. Consensus was obtained using the Research and Development/UCLA Appropriateness Method. Results were summarized using the Grading of Recommendations Assessment, Development, and Evaluation method. We developed 23 recommendations, 52 expert consensus statements, and 16 good practice statements covering the management of ECMO anticoagulation in three broad categories: general care and monitoring; perioperative care; and nonprocedural bleeding or thrombosis. Gaps in knowledge and research priorities were identified, along with three research focused good practice statements. CONCLUSIONS: The 91 statements focused on clinical care will form the basis for standardization and future clinical trials.


Asunto(s)
Anticoagulantes , Enfermedad Crítica , Oxigenación por Membrana Extracorpórea , Oxigenación por Membrana Extracorpórea/métodos , Humanos , Anticoagulantes/uso terapéutico , Anticoagulantes/administración & dosificación , Niño , Enfermedad Crítica/terapia , Recién Nacido , Lactante , Preescolar
11.
JAMA ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949829

RESUMEN

Importance: The US leads the world in bringing new medical products to market, but the ability to generate evidence to inform clinical practice in postmarket settings needs improvement. Although a diverse group of stakeholders is working to improve postmarket evidence generation, the role of private payers has been underappreciated. Observations: Payers are crucial allies in improving evidence generation because better data would better inform coverage decisions, their policies and practices influence the conduct of care and research, and their claims data are a source of real-world evidence used in medical product evaluation. In addition, payers have a stake in improving evidence generation because the kinds of evidence needed to inform health care and coverage decisions are often not available when a product enters the market and may not be generated without their involvement. Here, we describe several key steps payers could take to improve evidence generation, including participating in efforts to reduce administrative and financial barriers to the conduct of clinical trials, directly incentivizing evidence generation on high-priority questions by funding potential cost-saving trials, increasing engagement with the medical products industry on evidentiary needs for coverage decisions, and improving usability of claims data by reducing data lags and routinely recording unique device identifiers. Broad payer engagement with US Food and Drug Administration recommendations regarding evidence generation will ensure that the opportunities to participate in clinical research are extended to all communities and that evidence needed to inform care is generated in trials and surveillance systems that reflect the clinical reality across the US. Conclusions and Relevance: Increasing payer involvement in evidence generation can benefit all participants in the medical innovation ecosystem. The importance of payers in these efforts will continue to grow in response to imperatives to increase integration of care and research, engage a diverse set of communities in clinical research, and move toward alternative payment models.

12.
Scand J Psychol ; 65(1): 70-85, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37596807

RESUMEN

There is no doubt that extreme contexts (e.g., war zones and pandemics) represent substantial disruptions that force many companies to rethink the way they do business. With so much of the workforce now working remotely and concerns about resulting work alienation, we must ask this question: How can this be translated into the generational divide in workplaces based in extreme contexts? Using COVID-19 as an example trigger of extreme-context experience, therefore, we investigate generation as a moderator of the effects of extreme-context perception upon anxiety leading to alienation with subsequent behavioral outcomes on job insecurity, job satisfaction, and organizational citizenship behavior (OCB). A time-lagged survey procedure yielded 219 valid responses from a three-generation sample of employees working in multiple service organizations. The data were analyzed using partial least squares structural equation modeling (PLS-SEM). Our analysis suggested that intense extreme-context perception led to elevated anxiety and alienation, which, in turn, heightened job insecurity and worsened job satisfaction and OCB outcomes. Finally, during the experience of extreme-context times, generation was found to moderate our model, such that both Generation Y and Generation Z experienced higher anxiety due to extreme-context perception and hence higher job insecurity due to alienation compared with Generation X respondents. Our results endorse the criticality of implementing agile and generationally non-sectarian management for effectively functioning generationally diverse workforces in pandemic times.


Asunto(s)
Teletrabajo , Lugar de Trabajo , Humanos , Satisfacción en el Trabajo , Emociones , Percepción
13.
Med J Malaysia ; 79(1): 74-79, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38287761

RESUMEN

INTRODUCTION: Salmonella typhi could infect the intestinal tract and the bloodstream or invade body organs and secrete endotoxins. It is endemic in developing countries. It is increasingly evolving antimicrobial resistance to several commonly used antimicrobial agents. MATERIALS AND METHODS: A cross-sectional study was done at Iraqi Communicable Disease Control Center, where all confirmed cases of Salmonella typhi are reported, for a period 2019-2021. All demographic, epidemiological and clinical characteristics of patients, comorbidities, type of samples, distribution of S. typhi by age and gender, time distribution in each year and profile of bacterial resistance and sensitivity to antibiotics were gathered and analysed. RESULTS: Most samples were taken from blood. The mean age of cases during 2019, 2020 and 2021 was 18.7 ± 6.5, 17.7 ± 14.1 and 17.3 ± 12.8. Males constituted 56.7%, 58.5% and 39.8%, respectively. Some cases had comorbidities. Most cases had headache and fever. Some of them had nausea, diarrhoea, vomiting and epigastric pain. The age and sex were significantly associated with years of reporting. The most months of case reporting were June-July (2019 and 2021), Jan. -Feb. (2020). There was an obvious increase in S. typhi resistance to ceftriaxone (92.2%, 86.1%, 88.8%) and ampicillin (77.1%, 76.9%, 81.27%). There was a gradual increase in sensitivity to tetracycline (83.1%, 88.1%, 94%), cotrimoxazole (86.7%, 86.1%, 92.2%), ciprofloxacin (78.3%, 90.1%, 87.8%) and cefixime (77.7%, 72.3%, 72.7%). CONCLUSIONS: There was a sharp rise in resistance rates of the S. typhi in Iraq (during 2019-2021) to ceftriaxone and ampicillin, while there were highest sensitivity rates to imipenem, aztreonam and chloramphenicol. The following recommendations were made: (1) Improvement of general hygiene and food safety measures. (2) Emphasis on vaccination and surveillance of Salmonella infection. (3) Rational use of appropriate antibiotics through implementation of treatment guidelines. (5) Educate communities and travelers about the risks of S. typhi and its preventive measures.


Asunto(s)
Fiebre Tifoidea , Masculino , Humanos , Fiebre Tifoidea/tratamiento farmacológico , Fiebre Tifoidea/epidemiología , Fiebre Tifoidea/microbiología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Ceftriaxona/uso terapéutico , Irak/epidemiología , Estudios Transversales , Prevalencia , Farmacorresistencia Bacteriana , Pruebas de Sensibilidad Microbiana , Salmonella typhi , Ampicilina/uso terapéutico
14.
Magn Reson Med ; 89(1): 356-369, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36093915

RESUMEN

PURPOSE: To develop and validate a deep learning-based reconstruction framework for highly accelerated two-dimensional (2D) phase contrast (PC-MRI) data with accurate and precise quantitative measurements. METHODS: We propose a modified DL-ESPIRiT reconstruction framework for 2D PC-MRI, comprised of an unrolled neural network architecture with a Complex Difference estimation (CD-DL). CD-DL was trained on 155 fully sampled 2D PC-MRI pediatric clinical datasets. The fully sampled data ( n = 29 $$ n=29 $$ ) was retrospectively undersampled (6-11 × $$ \times $$ ) and reconstructed using CD-DL and a parallel imaging and compressed sensing method (PICS). Measurements of peak velocity and total flow were compared to determine the highest acceleration rate that provided accuracy and precision within ± 5 % $$ \pm 5\% $$ . Feasibility of CD-DL was demonstrated on prospectively undersampled datasets acquired in pediatric clinical patients ( n = 5 $$ n=5 $$ ) and compared to traditional parallel imaging (PI) and PICS. RESULTS: The retrospective evaluation showed that 9 × $$ \times $$ accelerated 2D PC-MRI images reconstructed with CD-DL provided accuracy and precision (bias, [95 % $$ \% $$ confidence intervals]) within ± 5 % $$ \pm 5\% $$ . CD-DL showed higher accuracy and precision compared to PICS for measurements of peak velocity (2.8 % $$ \% $$ [ - 2 . 9 $$ -2.9 $$ , 4.5] vs. 3.9 % $$ \% $$ [ - 11 . 0 $$ -11.0 $$ , 4.9]) and total flow (1.8 % $$ \% $$ [ - 3 . 9 $$ -3.9 $$ , 3.4] vs. 2.9 % $$ \% $$ [ - 7 . 1 $$ -7.1 $$ , 6.9]). The prospective feasibility study showed that CD-DL provided higher accuracy and precision than PICS for measurements of peak velocity and total flow. CONCLUSION: In a retrospective evaluation, CD-DL produced quantitative measurements of 2D PC-MRI peak velocity and total flow with ≤ 5 % $$ \le 5\% $$ error in both accuracy and precision for up to 9 × $$ \times $$ acceleration. Clinical feasibility was demonstrated using a prospective clinical deployment of our 8 × $$ \times $$ undersampled acquisition and CD-DL reconstruction in a cohort of pediatric patients.


Asunto(s)
Aprendizaje Profundo , Humanos , Niño , Estudios Retrospectivos , Estudios Prospectivos , Imagen por Resonancia Magnética , Microscopía de Contraste de Fase
15.
Phys Rev Lett ; 131(6): 061802, 2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37625052

RESUMEN

A test of CP invariance in Higgs boson production via vector-boson fusion has been performed in the H→γγ channel using 139 fb^{-1} of proton-proton collision data at sqrt[s]=13 TeV collected by the ATLAS detector at the LHC. The optimal observable method is used to probe the CP structure of interactions between the Higgs boson and electroweak gauge bosons, as described by an effective field theory. No sign of CP violation is observed in the data. Constraints are set on the parameters describing the strength of the CP-odd component in the coupling between the Higgs boson and the electroweak gauge bosons in two effective field theory bases: d[over ˜] in the HISZ basis and c_{HW[over ˜]} in the Warsaw basis. The results presented are the most stringent constraints on CP violation in the coupling between Higgs and weak bosons. The 95% C.L. constraint on d[over ˜] is derived for the first time and the 95% C.L. constraint on c_{HW[over ˜]} has been improved by a factor of 5 compared to the previous measurement.

16.
Phys Rev Lett ; 131(4): 042303, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37566833

RESUMEN

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

17.
Phys Rev Lett ; 131(4): 042301, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37566840

RESUMEN

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.

18.
Phys Rev Lett ; 131(4): 041901, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37566856

RESUMEN

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.

19.
Phys Rev Lett ; 131(17): 172301, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37955510

RESUMEN

This letter presents a measurement of the nuclear modification factor of large-radius jets in sqrt[s_{NN}]=5.02 TeV Pb+Pb collisions by the ATLAS experiment. The measurement is performed using 1.72 nb^{-1} and 257 pb^{-1} of Pb+Pb and pp data, respectively. The large-radius jets are reconstructed with the anti-k_{t} algorithm using a radius parameter of R=1.0, by reclustering anti-k_{t} R=0.2 jets, and are measured over the transverse momentum (p_{T}) kinematic range of 158

20.
Phys Rev Lett ; 131(10): 102302, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37739380

RESUMEN

The most precise measurements to date of the _{Λ}^{3}H lifetime τ and Λ separation energy B_{Λ} are obtained using the data sample of Pb-Pb collisions at sqrt[s_{NN}]=5.02 TeV collected by ALICE at the LHC. The _{Λ}^{3}H is reconstructed via its charged two-body mesonic decay channel (_{Λ}^{3}H→^{3}He+π^{-} and the charge-conjugate process). The measured values τ=[253±11(stat)±6(syst)] ps and B_{Λ}=[102±63(stat)±67(syst)] keV are compatible with predictions from effective field theories and confirm that the _{Λ}^{3}H structure is consistent with a weakly bound system.

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