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1.
Phys Rev Lett ; 132(17): 172302, 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38728735

ABSTRACT

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

2.
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.

3.
Sci Rep ; 14(1): 10318, 2024 May 05.
Article in English | MEDLINE | ID: mdl-38705884

ABSTRACT

Recent demonstrations of room-temperature lasing in optically pumped GeSn show promise for future CMOS compatible lasers for Si-photonics applications. However, challenges remain for electrically pumped devices. Investigation of the processes that limit device performance is therefore vital in aiding the production of future commercial devices. In this work, a combined experimental and modelling approach is utilised to explore the dominant loss processes in current devices. By manipulating the band structure of functioning devices using high hydrostatic pressure techniques at low temperature, the dominant carrier recombination pathways are identified. This reveals that 93 ± 5% of the threshold current is attributable to defect-related recombination at a temperature, T = 85 K. Furthermore, carrier occupation of L-valley states (carrier leakage) is responsible for 1.1 ± 0.3% of the threshold current, but this sharply increases to 50% with a decrease of just 30 meV in the L- Γ separation energy. This indicates that thermal broadening of a similar order may reproduce these adverse effects, limiting device performance at higher temperatures. Temperature dependent calculations show that carrier occupation of indirect valley L-states strongly affects the transparency carrier density and is therefore very sensitive to the Sn composition, leading to an effective operational temperature range for given Sn compositions and strain values. Recommendations for future device designs are proposed based on band structure and growth optimisations.

4.
IEEE Pulse ; 15(1): 9-14, 2024.
Article in English | MEDLINE | ID: mdl-38619927

ABSTRACT

Health Care Innovation is the creation, development, and translation of new and better solutions to health care challenges. At its core, this endeavor does not require extending the frontiers of science or the creation of new fundamental technologies. Rather, it is primarily focused on the use of existing science and established technologies in the design of new solutions to problems in health care. Successfully innovating for low- and middle-income countries (LMICs) requires a needs and stakeholder-driven approach to enable development and adoption of available, accessible, and acceptable solutions tailored to the specific need and context of care.


Subject(s)
Delivery of Health Care , Immersion , Humans , Developing Countries
5.
Phys Rev Lett ; 132(10): 109901, 2024 Mar 08.
Article in English | MEDLINE | ID: mdl-38518355

ABSTRACT

This corrects the article DOI: 10.1103/PhysRevLett.131.042301.

6.
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

7.
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.

8.
Kathmandu Univ Med J (KUMJ) ; 21(81): 17-22, 2023.
Article in English | MEDLINE | ID: mdl-37800420

ABSTRACT

Background Mucoid degeneration of anterior cruciate ligament is characterized by infiltration of mucoid-like material scattered throughout the anterior cruciate ligament substance. It is an uncommon condition, but previously, underdiagnosed or often misdiagnosed as an anterior cruciate ligament tear. Objective To present our early experiences with mucoid degeneration of anterior cruciate ligament in last five years in terms of clinical presentation and the outcomes of arthroscopic management. Method This was a retrospective descriptive cross-sectional study on patient who received arthroscopic debridement for mucoid degeneration of anterior cruciate ligament in Dhulikhel Hospital over five years period (2017 May to 2022 April). Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scale that has been translated and validated to be used in local (Nepali) language and context was used for evaluation of outcome evaluation. Result Twenty-one patients of mean age 44.21 years, predominantly females (18), were managed in five years period. The mean Western Ontario and McMaster Universities Osteoarthritis Index score was 16.33±10.47 with a range of 0 to 36 (11.57 to 21.09 at 95% confidence interval). The mean Western Ontario and McMaster Universities Osteoarthritis Index score converted on a scale of 0 to 100 was 17. Thirteen patients had isolated Mucoid degeneration of anterior cruciate ligament whereas nine others had associated either meniscal tear or chondral lesions. Conclusion Mucoid degeneration of anterior cruciate ligament could be a cause of knee pain in middle-aged patients and arthroscopic debridement can improve the patient's symptoms and provide a good functional outcome.


Subject(s)
Anterior Cruciate Ligament , Osteoarthritis , Middle Aged , Female , Humans , Adult , Male , Anterior Cruciate Ligament/pathology , Anterior Cruciate Ligament/surgery , Debridement , Retrospective Studies , Nepal , Cross-Sectional Studies , Magnetic Resonance Imaging , Osteoarthritis/pathology
9.
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.

10.
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

11.
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.

12.
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.

14.
Eur J Paediatr Dent ; 24(1): 15-19, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36853219

ABSTRACT

AIM: The aim of the study is to investigate the association between social capital and dental caries among 3-5-year-old preschool children in a rural region of southern India. METHODS: A cross-sectional study was conducted among 260 children ranging from 3 to 5 years-old and their parents from 13 preschools of the Udupi region of south India between December 2018, and February 2019. A 16-item Social Capital Scale (SCS) was used to collect data from the children's parents regarding their social capital. The diet history was collected from the parents and the children were examined for dental caries using the dmft index in their schools. CONCLUSION: Dental caries among preschool children had a negative association with parental social capital, and significantly contributed to variances in dental caries along with socioeconomic and dietary factors.


Subject(s)
Dental Caries , Social Capital , Child, Preschool , Humans , Cross-Sectional Studies , Dental Caries/epidemiology , Educational Status , Parents
15.
Adv Mater ; 35(17): e2209513, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36787625

ABSTRACT

Ferromagnetism in van der Waals systems, preserved down to a monolayer limit, attracted attention to a class of materials with general composition CrX3 (X=I, Br, and Cl), which are treated now as canonical 2D ferromagnets. Their diverse magnetic properties, such as different easy axes or varying and controllable character of in-plane or interlayer ferromagnetic coupling, make them promising candidates for spintronic, photonic, optoelectronic, and other applications. Still, significantly different magneto-optical properties between the three materials have been presenting a challenging puzzle for researchers over the last few years. Herewith, it is demonstrated that despite similar structural and magnetic configurations, the coupling between excitons and magnetization is qualitatively different in CrBr3 and CrI3 films. Through a combination of the optical spin pumping experiments with the state-of-the-art theory describing bound excitonic states in the presence of magnetization, we concluded that the hole-magnetization coupling has the opposite sign in CrBr3 and CrI3 and also between the ground and excited exciton state. Consequently, efficient spin pumping capabilities are demonstrated in CrBr3 driven by magnetization via spin-dependent absorption, and the different origins of the magnetic hysteresis in CrBr3 and CrI3 are unraveled.

16.
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

17.
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.

19.
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.

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