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1.
Phys Rev Lett ; 132(16): 162302, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38701458

ABSTRACT

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.

2.
Phys Rev Lett ; 132(4): 042301, 2024 Jan 26.
Article in English | MEDLINE | ID: mdl-38335364

ABSTRACT

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

3.
Article in English | MEDLINE | ID: mdl-38290219

ABSTRACT

Summary: Kabuki syndrome is a genetic disorder characterised by distinctive facial features, developmental delays, and multisystem congenital anomalies. Endocrine complications such as premature thelarche and short stature are common, whereas disorders of glycaemic control are less frequent. We describe a 23-year-old white female referred to the diabetes clinic for hyperglycaemia during haemodialysis. She was subsequently diagnosed with Kabuki syndrome based on characteristic clinical features, confirmed by detecting a heterozygous pathogenic variant in KMT2D. She was known to have had multiple congenital anomalies at birth, including complex congenital heart disease and a single dysplastic ectopic kidney, and received a cadaveric transplanted kidney at the age of 13. She had hyperglycaemia consistent with post-transplant diabetes mellitus (DM) and was started on insulin. Examination at the time revealed truncal obesity. She developed acute graft rejection and graft failure 14 months post-transplant and she was started on haemodialysis. Her blood glucose levels normalised post-graft explant, but she was hyperglycaemic again during haemodialysis at the age of 23. Given her clinical phenotype, negative diabetes antibodies and normal pancreas on ultrasound, she was assumed to have type 2 DM and achieved good glycaemic control with gliclazide. Learning points: Involve clinical genetics early in the investigative pathway of sick neonates born with multiple congenital anomalies to establish a diagnosis to direct medical care. Consider the possibility of Kabuki syndrome (KS) in the differential diagnoses in any neonate with normal karyotyping or microarray analysis and with multiple congenital anomalies (especially cardiac, renal, or skeletal), dysmorphic facial features, transient neonatal hypoglycaemia and failure to thrive. Consider the possibility of diabetes as an endocrine complication in KS patients who are obese or who have autoimmune disorders.

4.
Phys Rev Lett ; 131(19): 192301, 2023 Nov 10.
Article in English | MEDLINE | ID: mdl-38000395

ABSTRACT

Understanding the role of parton mass and Casimir color factors in the quantum chromodynamics parton shower represents an important step in characterizing the emission properties of heavy quarks. Recent experimental advances in jet substructure techniques have provided the opportunity to isolate and characterize gluon emissions from heavy quarks. In this Letter, the first direct experimental constraint on the charm-quark splitting function is presented, obtained via the measurement of the groomed shared momentum fraction of the first splitting in charm jets, tagged by a reconstructed D^{0} meson. The measurement is made in proton-proton collisions at sqrt[s]=13 TeV, in the low jet transverse-momentum interval of 15≤p_{T}^{jet ch}<30 GeV/c where the emission properties are sensitive to parton mass effects. In addition, the opening angle of the first perturbative emission of the charm quark, as well as the number of perturbative emissions it undergoes, is reported. Comparisons to measurements of an inclusive-jet sample show a steeper splitting function for charm quarks compared with gluons and light quarks. Charm quarks also undergo fewer perturbative emissions in the parton shower, with a reduced probability of large-angle emissions.

5.
Phys Rev Lett ; 131(10): 102302, 2023 Sep 08.
Article in English | MEDLINE | ID: mdl-37739380

ABSTRACT

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.

6.
Phys Rev Lett ; 131(4): 042303, 2023 Jul 28.
Article in English | MEDLINE | ID: mdl-37566833

ABSTRACT

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

7.
Phys Rev Lett ; 131(4): 042301, 2023 Jul 28.
Article in English | MEDLINE | ID: mdl-37566840

ABSTRACT

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.

8.
Phys Rev Lett ; 131(4): 041901, 2023 Jul 28.
Article in English | MEDLINE | ID: mdl-37566856

ABSTRACT

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.

9.
S Afr Med J ; 113(2): 84-90, 2023 02 01.
Article in English | MEDLINE | ID: mdl-36757071

ABSTRACT

BACKGROUND: Self-monitoring of blood glucose (SMBG) is a widely accepted standard of practice for management of insulin-dependentdiabetes, yet is largely unavailable in rural sub-Saharan Africa (SSA). This prospective cohort study is the first known report ofimplementation of SMBG in a rural, low-income country setting. OBJECTIVES: To evaluate adherence and change in clinical outcomes with SMBG implementation at two rural hospitals in Neno, Malawi. METHODS: Forty-eight patients with type 1 and insulin-dependent type 2 diabetes were trained to use glucometers and logbooks. Participantsmonitored preprandial glucose daily at rotating times and overnight glucose once a week. Healthcare providers were trained to evaluateglucose trends, and adjusted insulin regimens based on results. Adherence was measured as the frequency with which patients checked anddocumented blood glucose at prescribed times, while clinical changes were measured by change in glycated haemoglobin (HbA1c) over a6-month period. RESULTS: Participants brought their glucometers and logbooks to the clinic 95 - 100% of the time. Adherence with measuring glucose valuesand recording them in logbooks eight times a week was high (mean (standard deviation) 69.4% (15.7) and 69.0% (16.6), respectively). MeanHbA1c decreased from 9.0% (75 mmol/mol) at enrolment to 7.8% (62 mmol/mol) at 6 months (mean difference 1.2% (95% confidenceinterval (CI) 0.6 - 2.0; p=0.0005). The difference was greater for type 1 diabetes (1.6%; 95% CI 0.6 - 2.7; p=0.0031) than for type 2 diabetes(0.9%; 95% CI 0.1 - 1.9; p=0.0630). There was no documented increase in hypoglycaemic events, and no hospitalisations or deaths occurred. CONCLUSION: SMBG is feasible for patients with insulin-dependent diabetes in a rural SSA population, and may be associated with improvedHbA1c levels. Despite common misconceptions, all patients, regardless of education level, can benefit from SMBG. Further research onlong-term retention of SMBG activities and the benefits of increasing frequency of monitoring is warranted.


Subject(s)
Diabetes Mellitus, Type 1 , Diabetes Mellitus, Type 2 , Noncommunicable Diseases , Humans , Blood Glucose , Diabetes Mellitus, Type 1/drug therapy , Diabetes Mellitus, Type 2/epidemiology , Malawi/epidemiology , Prospective Studies , South Africa , Hypoglycemic Agents/therapeutic use , Insulin/therapeutic use , Blood Glucose Self-Monitoring/methods
10.
Int J Gynaecol Obstet ; 162(2): 525-531, 2023 Aug.
Article in English | MEDLINE | ID: mdl-36815725

ABSTRACT

OBJECTIVE: To explore Rwandan women's experiences, priorities, and preferences in accessing health care for non-pregnancy-related conditions and inform development of healthcare services related to these conditions among women of reproductive age at district hospitals and health centers in Rwanda. METHODS: We used a mixed-methods, exploratory sequential design. Semi-structured qualitative interviews were conducted with Rwandan women and coded thematically. A cross-sectional quantitative survey based on the qualitative data was administered to women attending health centers. RESULTS: Seventeen interviews and 150 surveys were conducted. Women identified conditions including back pain, gynecologic cancers, and abnormal vaginal bleeding as concerns. They generally reported positive experiences while accessing health care and knowledge of accessing health care. Barriers to care were identified, including transportation costs and inability to miss work. Women expressed a desire for more control over their care and the importance of maintaining their dignity while accessing health care. CONCLUSION: These findings provide useful insights to inform development of non-pregnancy-related healthcare services for women in Rwanda according to their priorities and preferences. The reported end-user health concerns, barriers to care, and diminished control over their care point to a need to evolve health systems around user-tailored needs and design interventions optimizing access whilst promoting dignified care.


Subject(s)
Health Priorities , Women's Health , Female , Humans , Rwanda , Cross-Sectional Studies , Qualitative Research , Health Services Accessibility
11.
Phys Rev Lett ; 128(25): 252003, 2022 Jun 24.
Article in English | MEDLINE | ID: mdl-35802430

ABSTRACT

The study of nuclei and antinuclei production has proven to be a powerful tool to investigate the formation mechanism of loosely bound states in high-energy hadronic collisions. The first measurement of the production of _{Λ}^{3}H in p-Pb collisions at sqrt[s_{NN}]=5.02 TeV is presented in this Letter. Its production yield measured in the rapidity interval -1

12.
BMJ Mil Health ; 2022 Jun 15.
Article in English | MEDLINE | ID: mdl-35705259

ABSTRACT

Moral injury is a relatively new, but increasingly studied, construct in the field of mental health, particularly in relation to current and ex-serving military personnel. Moral injury refers to the enduring psychosocial, spiritual or ethical harms that can result from exposure to high-stakes events that strongly clash with one's moral beliefs. There is a pressing need for further research to advance understanding of the nature of moral injury; its relationship to mental disorders such as posttraumatic stress disorder and depression; triggering events and underpinning mechanisms; and prevalence, prevention and treatment. In the meantime, military leaders have an immediate need for guidance on how moral injury should be addressed and, where possible, prevented. Such guidance should be theoretically sound, evidence-informed and ethically responsible. Further, the implementation of any practice change based on the guidance should contribute to the advancement of science through robust evaluation. This paper draws together current research on moral injury, best-practice approaches in the adjacent field of psychological resilience, and principles of effective implementation and evaluation. This research is combined with the military and veteran mental health expertise of the authors to provide guidance on the design, implementation and evaluation of moral injury interventions in the military. The paper discusses relevant training in military ethical practice, as well as the key roles leaders have in creating cohesive teams and having frank discussions about the moral and ethical challenges that military personnel face.

13.
Phys Rev Lett ; 128(17): 172005, 2022 Apr 29.
Article in English | MEDLINE | ID: mdl-35570422

ABSTRACT

The polarization of the Λ and Λ[over ¯] hyperons along the beam (z) direction, P_{z}, has been measured in Pb-Pb collisions at sqrt[s_{NN}]=5.02 TeV recorded with ALICE at the Large Hadron Collider (LHC). The main contribution to P_{z} comes from elliptic flow-induced vorticity and can be characterized by the second Fourier sine coefficient P_{z,s2}=⟨P_{z}sin(2φ-2Ψ_{2})⟩, where φ is the hyperon azimuthal emission angle and Ψ_{2} is the elliptic flow plane angle. We report the measurement of P_{z,s2} for different collision centralities and in the 30%-50% centrality interval as a function of the hyperon transverse momentum and rapidity. The P_{z,s2} is positive similarly as measured by the STAR Collaboration in Au-Au collisions at sqrt[s_{NN}]=200 GeV, with somewhat smaller amplitude in the semicentral collisions. This is the first experimental evidence of a nonzero hyperon P_{z} in Pb-Pb collisions at the LHC. The comparison of the measured P_{z,s2} with the hydrodynamic model calculations shows sensitivity to the competing contributions from thermal and the recently found shear-induced vorticity, as well as to whether the polarization is acquired at the quark-gluon plasma or the hadronic phase.

14.
Phys Rev Lett ; 128(10): 102001, 2022 Mar 11.
Article in English | MEDLINE | ID: mdl-35333086

ABSTRACT

This article presents groomed jet substructure measurements in pp and Pb-Pb collisions at sqrt[s_{NN}]=5.02 TeV with the ALICE detector. The soft drop grooming algorithm provides access to the hard parton splittings inside a jet by removing soft wide-angle radiation. We report the groomed jet momentum splitting fraction, z_{g}, and the (scaled) groomed jet radius, θ_{g}. Charged-particle jets are reconstructed at midrapidity using the anti-k_{T} algorithm with resolution parameters R=0.2 and R=0.4. In heavy-ion collisions, the large underlying event poses a challenge for the reconstruction of groomed jet observables, since fluctuations in the background can cause groomed parton splittings to be misidentified. By using strong grooming conditions to reduce this background, we report these observables fully corrected for detector effects and background fluctuations for the first time. A narrowing of the θ_{g} distribution in Pb-Pb collisions compared to pp collisions is seen, which provides direct evidence of the modification of the angular structure of jets in the quark-gluon plasma. No significant modification of the z_{g} distribution in Pb-Pb collisions compared to pp collisions is observed. These results are compared with a variety of theoretical models of jet quenching, and provide constraints on jet energy-loss mechanisms and coherence effects in the quark-gluon plasma.

15.
Phys Rev Lett ; 128(1): 012001, 2022 Jan 07.
Article in English | MEDLINE | ID: mdl-35061479

ABSTRACT

The p_{T}-differential production cross sections of prompt D^{0}, Λ_{c}^{+}, and Σ_{c}^{0,++}(2455) charmed hadrons are measured at midrapidity (|y|<0.5) in pp collisions at sqrt[s]=13 TeV. This is the first measurement of Σ_{c}^{0,++} production in hadronic collisions. Assuming the same production yield for the three Σ_{c}^{0,+,++} isospin states, the baryon-to-meson cross section ratios Σ_{c}^{0,+,++}/D^{0} and Λ_{c}^{+}/D^{0} are calculated in the transverse momentum (p_{T}) intervals 2

16.
J Clin Monit Comput ; 36(2): 325-334, 2022 04.
Article in English | MEDLINE | ID: mdl-33492490

ABSTRACT

Electrical impedance tomography (EIT) is used in lung physiology monitoring. There is evidence that EIT is linearly associated with global tidal volume (VT) in clinically healthy patients where no positive end-expiratory pressure (PEEP) is applied. This linearity has not been challenged by altering lung conditions. The aim of this study was to determine the effect of PEEP on VT estimation, using EIT technology and spirometry, and observe the stability of the relationship under changing lung conditions. Twelve male castrated cattle (Steer), mean age 7.8 months (SD ± 1.7) were premedicated with xylazine followed by anaesthesia induction with ketamine and maintenance with halothane in oxygen via an endotracheal tube. An EIT belt was applied around the thorax at the level of the fifth intercostal space. Volume controlled ventilation was used. PEEP was increased in a stepwise manner from 0 to 5, 10 and 15 cmH2O. At each PEEP, the VT was increased stepwise from 5 to 10 and 15 mL kg-1. After a minute of stabilisation, total impedance change (VTEIT), using EIT and VT measured by a spirometer connected to a flow-partitioning device (VTSpiro) was recorded for the following minute before changing ventilator settings. Data was analysed using linear regression and multi variable analysis. There was a linear relationship between VTEIT and VTSpiro at all levels of PEEP with an R2 of 0.71, 0.68, 0.63 and 0.63 at 0, 5, 10 and 15 cmH2O, respectively. The variance in VTEIT was best described by peak inspiratory pressure (PIP) and PEEP (adjusted R2 0.82) while variance in VTSpiro was best described by PIP and airway deadspace (adjusted R2 0.76). The relationship between VTEIT and VTSpiro remains linear with changes in tidal volume, and stable across altered lung conditions. This may have application for monitoring and assessment in vivo.


Subject(s)
Positive-Pressure Respiration , Tomography , Animals , Cattle , Electric Impedance , Humans , Male , Positive-Pressure Respiration/methods , Tidal Volume , Tomography/methods , Tomography, X-Ray Computed
17.
Phys Rev Lett ; 127(20): 202301, 2021 Nov 12.
Article in English | MEDLINE | ID: mdl-34860039

ABSTRACT

The prompt production of the charm baryon Λ_{c}^{+} and the Λ_{c}^{+}/D^{0} production ratios were measured at midrapidity with the ALICE detector in pp and p-Pb collisions at sqrt[s_{NN}]=5.02 TeV. These new measurements show a clear decrease of the Λ_{c}^{+}/D^{0} ratio with increasing transverse momentum (p_{T}) in both collision systems in the range 2

18.
Phys Rev Lett ; 127(17): 172301, 2021 Oct 22.
Article in English | MEDLINE | ID: mdl-34739260

ABSTRACT

This Letter presents the first experimental evidence of the attractive strong interaction between a proton and a ϕ meson. The result is obtained from two-particle correlations of combined p-ϕ⊕ p[over ¯]-ϕ pairs measured in high-multiplicity pp collisions at sqrt[s]=13 TeV by the ALICE Collaboration. The spin-averaged scattering length and effective range of the p-ϕ interaction are extracted from the fully corrected correlation function employing the Lednický-Lyuboshits approach. In particular, the imaginary part of the scattering length vanishes within uncertainties, indicating that inelastic processes do not play a prominent role for the p-ϕ interaction. These data demonstrate that the interaction is dominated by elastic p-ϕ scattering. Furthermore, an analysis employing phenomenological Gaussian- and Yukawa-type potentials is conducted. Under the assumption of the latter, the N-ϕ coupling constant is found to be g_{N-ϕ}=0.14±0.03(stat)±0.02(syst). This work provides valuable experimental input to accomplish a self-consistent description of the N-ϕ interaction, which is particularly relevant for the more fundamental studies on partial restoration of chiral symmetry in nuclear medium.

19.
Phys Rev Lett ; 127(9): 092302, 2021 Aug 27.
Article in English | MEDLINE | ID: mdl-34506195

ABSTRACT

The event-by-event correlations between three flow amplitudes are measured for the first time in Pb-Pb collisions, using higher-order symmetric cumulants. We find that different three-harmonic correlations develop during the collective evolution of the medium when compared to correlations that exist in the initial state. These new results cannot be interpreted in terms of previous lower-order flow measurements since contributions from two-harmonic correlations are explicitly removed in the new observables. A comparison to Monte Carlo simulations provides new and independent constraints for the initial conditions and system properties of nuclear matter created in heavy-ion collisions.

20.
Phys Rev Lett ; 127(4): 042302, 2021 Jul 23.
Article in English | MEDLINE | ID: mdl-34355943

ABSTRACT

A measurement of dielectron production in proton-proton (pp) collisions at sqrt[s]=13 TeV, recorded with the ALICE detector at the CERN LHC, is presented in this Letter. The data set was recorded with a reduced magnetic solenoid field. This enables the investigation of a kinematic domain at low dielectron (ee) invariant mass m_{ee} and pair transverse momentum p_{T,ee} that was previously inaccessible at the LHC. The cross section for dielectron production is studied as a function of m_{ee}, p_{T,ee}, and event multiplicity dN_{ch}/dη. The expected dielectron rate from hadron decays, called hadronic cocktail, utilizes a parametrization of the measured η/π^{0} ratio in pp and proton-nucleus collisions, assuming that this ratio shows no strong dependence on collision energy at low transverse momentum. Comparison of the measured dielectron yield to the hadronic cocktail at 0.15

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