Cryopreservation of bovine semen using extract of Cinnamomum zeylanicum

BACKGROUND

Antioxidants minimise oxidative stress and enhance sperm quality in the process of cryopreservation.

OBJECTIVE

To assess the impact of Cinnamomum zeylanicum extract as an additive during the post-dilution and post-thaw stages of Murrah buffalo semen cryopreservation.

MATERIALS AND METHODS

The semen sample was diluted using Tris-Egg-Yolk-Citric-Acid-Fructose-Glycerol extender and subsequently divided into three groups: Group 1, TEYCAFG without any additives or controls (C); Group 2, TEYCAFG fortified with a 50 ug/mL aqueous extract of cinnamon (T1); and Group 3, TEYCAFG fortified with a 50 ug/mL ethanolic extract of cinnamon (T2). The evaluation included an assessment of progressive motility, live spermatozoa, sperm abnormalities, HOST, CMPT, and enzyme leakage (GOT and GPT) at both the post-dilution and post-thaw stages.

RESULTS

The groups that received cinnamon supplementation demonstrated statistically significant improvements (p<0.05) in various parameters, including an increase in the progressive motility, live spermatozoa, and HOS-positive spermatozoa, as well as greater distance traveled by vanguard spermatozoa compared to the control group. Furthermore, the cinnamon-added groups exhibited a significant decrease (p<0.05) in the percentage of sperm abnormalities and lower enzyme leakage (GOT and GPT) in post-thawed semen.

CONCLUSION

Aqueous extract of C. zeylanicum at a concentration of 50 µg/mL provides superior protection of sperm structures and functions as compared to both the ethanolic extract of C. zeylanicum at the same concentration and the control group. Doi.org/10.54680/fr24310110712.

Emergence of Long-Range Angular Correlations in Low-Multiplicity Proton-Proton Collisions

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 Collapse

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First Measurement of the |t| Dependence of Incoherent J/ψ Photonuclear Production

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.

The academic progress of female general surgery and orthopaedic surgery trainees in South Africa

BACKGROUND

Globally, medical institutes have seen an increase in female graduates, however surgical disciplines remain male-dominated. An epidemiological shift towards non-communicable diseases and trauma may result in a shortage of surgical specialists. One strategy to improve the surgical workforce is the recruitment of female graduates.

METHODS

A non-validated questionnaire was administered to females registered for the Master of Medicine (MMED) degree in General and Orthopaedic Surgery at the University of KwaZulu-Natal (UKZN) between 2000 and 2015. The study evaluated reasons for choice of surgery as a career, challenges faced on the domestic and work front, as well as factors that assisted with successful completion of training.

RESULTS

Seventy-two female trainees in General Surgery and Orthopaedics were identified from the UKZN databases. The contact details for 62 of these trainees were available. The overall response rate was 71.0% (44/62). A total of 95.5% (42/44) of participants selected surgery due to a passion for the field. Major challenges identified were a poor home and work-life balance (72.1%, 31/43) and poor working conditions (62.8%, 27/43). Female trainees perceived that they were viewed as inferior by patients (65.9%, 29/44). Successful trainees had a good home support system (89.3%, 25/28) and mentorship during training (60.7%, 17/28), and 85.7% (24/28) did not regret their career choice.

CONCLUSION

The recruitment and retention of females in surgery will contribute to maintaining an adequate surgical workforce. Training programmes need to improve work-life balance without compromising on producing competent surgeons. Improved visibility of female surgeons in leadership roles should be encouraged to promote mentorship and recruitment of trainees.

The Outcomes of Involutional Ptosis Surgeries in a Single Tertiary Center

PURPOSE

To report the surgical outcome of anterior approach primary ptosis surgery in a tertiary center and to compare redo surgical rates between different grades of surgeons.

METHODS

This is a Retrospective review of series of annual audits. All involutional/aponeurosis-disinsertion ptosis surgeries performed at Moorfields Eye-hospital (MEH) between January 01, 2016 and December 31, 2019 were included. Only primary surgery was included. The following data were collected; number of surgeries per year, number of patients, demographics data, grades of surgeons, success rate, redo surgery rate from different grades of surgeons, complications rate and patients' satisfaction.

RESULTS

During the study period, 1191 ptosis surgery were performed, with 899 (75%) cases being involutional/aponeurosis-disinsertion ptosis. The mean redo surgery rate within one year from the primary surgery was 10.5% and the mean complication rate was 1.0%, with 78.95% of patients reported being satisfied with the results of the surgery, having no difference between surgeon's grades. The redo surgery rate was higher for cases performed by a junior surgeon (fellow/registrar) (64.26%) than by a consultant (38.94%).

CONCLUSIONS

We report the success rate of a large cohort of primary involutional ptosis surgery performed at the ophthalmic-specialist tertiary center. The success and complication rates are comparable to the literature at 90% and 1%, respectively. Redo surgeries were more frequently required when performed by junior surgeons compared to the consultants, whereas the patient satisfaction level did not differ between different grades of surgeons.

ψ(2S) Suppression in Pb-Pb Collisions at the LHC

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 Collapse

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Measurements of Groomed-Jet Substructure of Charm Jets Tagged by D^{0} Mesons in Proton-Proton Collisions at sqrt[s]=13 TeV

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.

IMPLICATION OF THREAT FACTORS AND PREEXISTING DISORDERS IN DIFFERENT ISCHEMIC STROKE SUBGROUPS IN ELDERLY PEOPLE: A SYSTEMATIC STUDY

Ischemic stroke is a major health issue, especially for the older population and it may have severe effects. Stroke diagnosis and treatment have advanced over the last 20 years, which has resulted in considerable reductions in death, long-term impairment, and the need for institutional care. Younger age groups have seen the majority of trials for acute, interventional, and preventive therapy. The purpose of this research was to identify distinct subgroups of older people who had suffered an ischemic stroke and examine the role that risk factors and previous illnesses played in their development. Ischemic stroke risk factors varied by age, gender and exhibited their own unique features. Smoking, cholesterol, and psychological/emotional stress were shown to have the greatest prevalence (p<0.06) among stroke patients aged 45-60. Smoking is associated with a significant (p<0.07) decline in health in elderly people. Our results imply that there are significant patterns of risk factors and preexisting illnesses among the various subgroups of older people who have had an ischemic stroke. Atherosclerotic (large-artery) and cardio embolic (small-artery) ischemic strokes were shown to be the most prevalent among the elderly. Strong associations were found between these subtypes and other risk factors, including higher cholesterol, diabetes, high blood pressure, and atrial fibrillation. This research emphasizes the need for individualized preventative methods and therapeutic therapy, as well as the need to recognize the variability of ischemic stroke in the elderly.

Evaluation of the accuracy of the Asanté assay as a point-of-care rapid test for HIV-1 recent infections using serum bank specimens from blood donors in South Africa, July 2018 - August 2021

BACKGROUND

Point-of-care (POC) rapid recency testing can be used as a cost-effective tool to identify recently infected individuals (i.e. infected within the last 12 months) in near-real time, support epidemic control and identify hotspots for transmission as part of recent infection surveillance.

OBJECTIVE

To evaluate the performance of the Asanté (HIV-1) rapid recency assay as a POC rapid test among blood donors in South Africa (SA).

METHODS

The study was a cross-sectional and validity study of the Asanté HIV-1 Rapid Recency Assay performed on 715 consecutively archived plasma donor specimens from the SA National Blood Services to determine their recency and established HIV infection status. ELISA and rapid assays for HIV antibody detection were used as the reference-testing standard for confirming an infection, while the Maxim HIV-1 limiting antigen (LAg) avidity assay was used as a reference for comparing HIV recency status. Validity tests (sensitivity, specificity, negative and positive predictive values) and Cohen-Kappa tests of the agreement were conducted to compare the Asanté HIV-1 rapid recency assay results with the reference tests.

RESULTS

Of the 715 studied blood samples, 63.1% (n=451/715) were confirmed to be HIV-positive based on the reference standard. The sensitivity and specificity of the Asanté HIV-1 rapid recency assay in diagnosing established HIV infection compared to the ELISA were 98.4% (95% CI 96.7 - 99.3) and 99.6% (95% CI 97.6 - 100), respectively. Compared with HIV rapid assay, the sensitivity and specificity of the Asanté HIV-1 rapid recency assay was 98.7% (95% CI 97.0 - 99.4) and 99.2% (95% CI 97.1 - 100), respectively. Of the 451 HIV-positive blood samples, 43% were confirmed as recent HIV infections by the Maxim HIV-1 LAg avidity assay. There was high agreement between the Asanté HIV-1 rapid recency assay and the Maxim HIV-1 LAg avidity assay (94.1%, k=0.879, p<0.0001). The sensitivity and specificity of the Asante HIV-1 assay was 89.4% (95% CI 84.0 - 93.0) and 97.7% (95% CI 94.8 - 99.0), respectively.

CONCLUSION

The Asanté HIV-1 rapid recency assay test results demonstrated high accuracy (>90%) compared with the HIV ELISA and rapid assays for determining established infection and the Maxim HIV-1 LAg avidity assay for classifying recent HIV-1 infections. The assay's sensitivity for established infections was below the World Health Organization criteria (<99%) for POC devices. The Asanté HIV-1 rapid recency assay can be used to distinguish between recent and long-term infections, but may not be considered a POC test for determining HIV infection.

Measurement of the Lifetime and Λ Separation Energy of _{Λ}^{3}H

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.

Measurements of jet multiplicity and jet transverse momentum in multijet events in proton-proton collisions at s=13TeV

Multijet events at large transverse momentum (p T ) are measured at s = 13 Te V using data recorded with the CMS detector at the LHC, corresponding to an integrated luminosity of 36.3 fb - 1 . The multiplicity of jets with p T > 50 Ge V that are produced in association with a high-p T dijet system is measured in various ranges of the p T of the jet with the highest transverse momentum and as a function of the azimuthal angle difference Δ ϕ 1 , 2 between the two highest p T jets in the dijet system. The differential production cross sections are measured as a function of the transverse momenta of the four highest p T jets. The measurements are compared with leading and next-to-leading order matrix element calculations supplemented with simulations of parton shower, hadronization, and multiparton interactions. In addition, the measurements are compared with next-to-leading order matrix element calculations combined with transverse-momentum dependent parton densities and transverse-momentum dependent parton shower.

Azimuthal Correlations within Exclusive Dijets with Large Momentum Transfer in Photon-Lead Collisions

The structure of nucleons is multidimensional and depends on the transverse momenta, spatial geometry, and polarization of the constituent partons. Such a structure can be studied using high-energy photons produced in ultraperipheral heavy-ion collisions. The first measurement of the azimuthal angular correlations of exclusively produced events with two jets in photon-lead interactions at large momentum transfer is presented, a process that is considered to be sensitive to the underlying nuclear gluon polarization. This study uses a data sample of ultraperipheral lead-lead collisions at sqrt[s_{NN}]=5.02  TeV, corresponding to an integrated luminosity of 0.38  nb^{-1}, collected with the CMS experiment at the LHC. The measured second harmonic of the correlation between the sum and difference of the two jet transverse momentum vectors is found to be positive, and rising, as the dijet transverse momentum increases. A well-tuned model that has been successful at describing a wide range of proton scattering data from the HERA experiments fails to describe the observed correlations, suggesting the presence of gluon polarization effects.

Measurement of the J/ψ Polarization with Respect to the Event Plane in Pb-Pb Collisions at the LHC

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 Collapse

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First Measurement of Antideuteron Number Fluctuations at Energies Available at the Large Hadron Collider

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.

Enhanced Deuteron Coalescence Probability in Jets

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.

Measurement of the mass dependence of the transverse momentum of lepton pairs in Drell-Yan production in proton-proton collisions at s=13TeV

The double differential cross sections of the Drell-Yan lepton pair (ℓ + ℓ - , dielectron or dimuon) production are measured as functions of the invariant mass m ℓ ℓ , transverse momentum p T ( ℓ ℓ ) , and φ η ∗ . The φ η ∗ observable, derived from angular measurements of the leptons and highly correlated with p T ( ℓ ℓ ) , is used to probe the low-p T ( ℓ ℓ ) region in a complementary way. Dilepton masses up to 1Te V are investigated. Additionally, a measurement is performed requiring at least one jet in the final state. To benefit from partial cancellation of the systematic uncertainty, the ratios of the differential cross sections for various m ℓ ℓ ranges to those in the Z mass peak interval are presented. The collected data correspond to an integrated luminosity of 36.3fb - 1 of proton-proton collisions recorded with the CMS detector at the LHC at a centre-of-mass energy of 13Te V . Measurements are compared with predictions based on perturbative quantum chromodynamics, including soft-gluon resummation.

Microbiological analysis and predictors of gallbladder infection with antimicrobial susceptibility patterns in an HIV setting

Background South Africa has a high prevalence of people living with human immunodeficiency virus (HIV; PLWH) who have shown to affect the prevalence and severity of infection and sepsis particularly gallbladder disease.  Empirical Antimicrobial (EA) therapy for acute cholecystitis (AC) is based largely on bacteria colonisation of bile (bacteriobilia) and antimicrobial susceptibility patterns (antibiograms) obtained from the developed world where the prevalence of PLWH is very low. In an ever-emerging era of increasing antimicrobial resistance, monitoring and updating local antibiograms is underscored.  Objective Due to the paucity of data available locally to guide treatment we found it pertinent to examine gallbladder bile for bacteriobilia and antibiograms in a setting with a high prevalence of PLWH to determine if this may demand a review of our local antimicrobial policies for gallbladder infections for both EA and pre-operative antimicrobial prophylaxis (PAP) for laparoscopic cholecystectomies (LC). Methodology A retrospective observational descriptive study was undertaken at King Edward VIII Hospital, Durban, KwaZulu-Natal, South Africa. Hospital records were reviewed for all patients undergoing cholecystectomy over a 3-year period. Gallbladder bacteriobilia and antibiograms were assessed and compared between PLWH and HIV uninfected (HIV-U). Pre-operative age, ERCP, PCT, CRP and NLR were used as predictors for bacteriobilia. Statistical analyses were performed using R Project and p values of less than 0.05 were considered as statistically significant. Results There were no differences in bacteriobilia or antibiograms between PLWH and HIV-U. There was >30% resistance to amoxicillin/clavulanate and cephalosporins. Aminoglycoside-based therapy, had good susceptibility patterns whilst carbapenem-based therapy demonstrated the lowest resistance levels. ERCP and age were predictors of bacteriobilia (p<0.001 and 0.002 respectively). PCT, CRP and NLR were not. Conclusion PLWH should follow the same PAP and EA recommendations as HIV-U. For EA, we recommend, a combination of amoxicillin/clavulanate with aminoglycoside-based therapy (amikacin or gentamycin) or piperacillin/tazobactam as monotherapy. Carbapenem-based therapy should be reserved for drug resistant species. For PAP, we recommend the routine use in older patients and patients with history of ERCP undergoing LC.

Dynamics of reactive oxygen species and lignin biosynthesis during leaf spot disease of Withania somnifera (L.) Dunal

Withania somnifera is an important medicinal plant, however, its cultivation and quality are compromised due to infestation by leaf spot disease caused by the fungus Alternaria alternata. To decipher suitable strategies against the disease, studies on post-infectional changes are important. Reactive oxygen species (ROS) are critical as they cross-talk with other defense signaling pathways. Our study involved the analysis of ROS-generating and scavenging systems in the healthy and diseased leaf samples of W. somnifera and ROS-driven downstream defence pathways. DAB and NBT assays for ROS detection, spectrophotometric and in gel assays for ROS scavenging enzymes, thioglycolic acid (TGA) based assay and histochemical staining for lignin content and qRT-PCR for transcript-level expression studies were performed. Leaf spot infection in W. somnifera led to increased NADPH oxidase activity and ROS accumulation in the infected leaves which were supported by the enhanced antioxidant enzyme activities. Leaf spot infected leaves exhibited increased lignin content with higher expression of lignin biosynthesis genes. In addition, the transcript levels of defense-related genes, NPR1 and PR genes were also upregulated. The present work provides insights into the response of leaf spot disease in invoking the defense-related signaling in W. somnifera. It demonstrates the cross-talk between ROS and lignin biosynthesis. This work identifies potential targets for developing future strategies to confer disease resistance against leaf spot pathogen in W. somnifera.

The supernumerary registrar experience in KwaZulu-Natal

BACKGROUND

We sought to assess the experiences of trainees enrolled in the supernumerary registrar programme at the University of KwaZulu-Natal, South Africa, with a specific focus on their assimilation into host clinical units and their intentions to return to their home countries upon completion of the training.

METHODS

This was a cross-sectional survey involving 50 supernumerary registrars attached to six academic hospitals affiliated with the University of KwaZulu-Natal. The survey collected information on registrar's demographics and financial support, speciality, opportunities for advanced training in their home country, assimilation into host clinical units and intentions to return home upon completing the training. The survey data were analysed using descriptive statistics.

RESULTS

The majority of supernumeraries were < 36 years old (n = 32, 64%), male (n = 31, 62%), and self-funded (n = 31, 62%). Only a few supernumeraries were associated with a training facility in their home country (n = 9, 18%). Most supernumeraries (n = 44, 88%) reported not having an equivalent training programme in their home country. Awareness of the programme was predominantly acquired through self-research (n = 35, 70%), and the application process was perceived as problematic by many supernumeraries (n = 46, 92%). Most supernumeraries (n = 43, 86%) assimilated into their host clinical units, and nearly one-third (n = 16, 32%) did not plan on returning home upon completion of their training.

CONCLUSION

Most supernumerary registrars assimilate into host clinical units and play an important role in service delivery during their training. Mechanisms should be put in place to facilitate retention of these individuals in their home countries upon completion of their training.

Optical design and fabrication of zinc selenide microlens array with extended depth of focus for biomedical imaging

Optical coherence tomography is a well-known technique for the optical imaging biological tissues. However, the depth scanning range of high-resolution optical coherence tomography is restricted by its depth of focus. In this study, a Zinc Selenide (ZnSe) Microlens Array (MLA) is employed to overcome the depth-of-focus limitation of optical coherence tomography. The ZnSe material with a low Abbe number and high chromatic dispersion extends the depth of focus with transverse resolution. The ZnSe MLA focused the incident light (from visible to near-infrared (NIR) region) on multiple focal planes with the uniform distribution of light over a biological tissue. The MLA is designed using Zemax OpticStudio software and fabricated via a single-point diamond-turning based on Slow Tool Servo (STS) configuration. STS machining has the unique advantage of offering larger degrees of freedom with no additional baggage, thereby reducing the setup time. The experimental results show the effectiveness of the STS machining process in fabricating ZnSe MLA with desired accuracies. The characterization of fabricated MLA using Coherence Correlation Interferometry (CCI) depicts uniform lenslets with no structural and positional distortion, with a total error of 32 nm within the tolerance limit.

Measurements of the associated production of a W boson and a charm quark in proton-proton collisions at s = 8 TeV

Measurements of the associated production of a W boson and a charm ( c ) quark in proton-proton collisions at a centre-of-mass energy of 8 TeV are reported. The analysis uses a data sample corresponding to a total integrated luminosity of 19.7 fb - 1 collected by the CMS detector at the LHC. The W bosons are identified through their leptonic decays to an electron or a muon, and a neutrino. Charm quark jets are selected using distinctive signatures of charm hadron decays. The product of the cross section and branching fraction σ ( pp → W + c + X ) B ( W → ℓ ν ) , where ℓ = e or μ , and the cross section ratio σ ( pp → W + + c ¯ + X ) / σ ( pp → W - + c + X ) are measured in a fiducial volume and differentially as functions of the pseudorapidity and of the transverse momentum of the lepton from the W boson decay. The results are compared with theoretical predictions. The impact of these measurements on the determination of the strange quark distribution is assessed.

Prevalence and Associated Factors of Cesarean Section in Dhulikhel Hospital, Kathmandu University Hospital

Background The Cesarean Section (CS) is a major obstetric life-saving procedure used to avoid pregnancy and childbirth complications. Cesarean sections are becoming more popular across the world, as well as in Nepal. Objective To assess the prevalence of cesarean section and its associated factors among women in Dhulikhel, Nepal. Method A cross-sectional study was conducted where 1246 pregnant women of age 15-45 years, admitted and delivered in hospital, were selected through purposive sampling technique and interviewed using structured questionnaires in Dhulikhel Hospital, Kathmandu University Hospital, Kavre, Nepal. Result The prevalence of cesarean section among women was 39.7% where the most common indication was previous cesarean section with scar tenderness, 27.9%. Half of the participants, i.e. 50.6%, were primigravida. Majority of women, 97.5% had done their antenatal checkup and among them 74.8% had their checkup in Dhulikhel Hospital, Kathmandu University Hospital. Most of them, i.e.76.2% had emergency cesarean section and 69.5% had primary cesarean section. Women of the age group 30-45 years (AOR=2.23) and women with higher secondary education level (AOR=2.03) were two times more likely to perform cesarean section. Women involved in service (AOR=1.37) and business (AOR=1.23) had greater odds of performing cesarean section than homemakers. Women giving birth to infants weighing 3.51- 5.00 kg were more likely to perform cesarean section (AOR=1.33). Conclusion The prevalence of cesarean section is noticeably high where the educated, employed and higher aged women are more inclined to cesarean section. More obstetric factors could be explored to determine the rise in cesarean section in Nepal which can help in decision making for clinicians.

Search for Higgs Boson Pair Production in the Four b Quark Final State in Proton-Proton Collisions at sqrt[s]=13 TeV

A search for pairs of Higgs bosons produced via gluon and vector boson fusion is presented, focusing on the four b quark final state. The data sample consists of proton-proton collisions at a center-of-mass energy of 13 TeV, collected with the CMS detector at the LHC, and corresponds to an integrated luminosity of 138  fb^{-1}. No deviation from the background-only hypothesis is observed. A 95% confidence level upper limit on the Higgs boson pair production cross section is observed at 3.9 times the standard model prediction for an expected value of 7.8. Constraints are also set on the modifiers of the Higgs field self-coupling, κ_{λ}, and of the coupling of two Higgs bosons to two vector bosons, κ_{2 V}. The observed (expected) allowed intervals at the 95% confidence level are -2.3<κ_{λ}<9.4 (-5.0<κ_{λ}<12.0) and -0.1<κ_{2 V}<2.2 (-0.4<κ_{2 V}<2.5). These are the most stringent observed constraints to date on the HH production cross section and on the κ_{2 V } coupling.

Search for Flavor-Changing Neutral Current Interactions of the Top Quark and Higgs Boson in Final States with Two Photons in Proton-Proton Collisions at sqrt[s]=13 TeV

Proton-proton interactions resulting in final states with two photons are studied in a search for the signature of flavor-changing neutral current interactions of top quarks (t) and Higgs bosons (H). The analysis is based on data collected at a center-of-mass energy of 13 TeV with the CMS detector at the LHC, corresponding to an integrated luminosity of 137  fb^{-1}. No significant excess above the background prediction is observed. Upper limits on the branching fractions (B) of the top quark decaying to a Higgs boson and an up (u) or charm (c) quark are derived through a binned fit to the diphoton invariant mass spectrum. The observed (expected) 95% confidence level upper limits are found to be 0.019% (0.031%) for B(t→Hu) and 0.073% (0.051%) for B(t→Hc). These are the strictest upper limits yet determined.

Search for Resonances Decaying to Three W Bosons in Proton-Proton Collisions at sqrt[s]=13 TeV

A search for resonances decaying into a W boson and a radion, where the radion decays into two W bosons, is presented. The data analyzed correspond to an integrated luminosity of 138  fb^{-1} recorded in proton-proton collisions with the CMS detector at sqrt[s]=13  TeV. One isolated charged lepton is required, together with missing transverse momentum and one or two massive large-radius jets, containing the decay products of either two or one W bosons, respectively. No excess over the background estimation is observed. The results are combined with those from a complementary channel with an all-hadronic final state, described in an accompanying paper. Limits are set on parameters of an extended warped extra-dimensional model. These searches are the first of their kind at the LHC.

Probing Charm Quark Dynamics via Multiparticle Correlations in Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

Multiparticle azimuthal correlations of prompt D^{0} mesons are measured in Pb-Pb collisions at a nucleon-nucleon center-of-mass energy of sqrt[s_{NN}]=5.02  TeV. For the first time, a four-particle cumulant method is used to extract the second Fourier coefficient of the azimuthal distribution (v_{2}) of D^{0} mesons as a function of event centrality and the D^{0} transverse momentum. The ratios of the four-particle v_{2} values to previously measured two-particle cumulant results provide direct experimental access to event-by-event fluctuations of charm quark azimuthal anisotropies. These ratios are also found to be comparable to those of inclusive charged particles in the event. However, hints of deviations are seen in the most central and peripheral collisions. To investigate the origin of flow fluctuations in the charm sector, these measurements are compared to a model implementing fluctuations of charm quark energy loss via collisional or radiative processes in the quark-gluon plasma. These models cannot quantitatively describe the data over the full transverse momentum and centrality ranges, although the calculations with collisional energy loss provide a better description of the data.

First Search for Exclusive Diphoton Production at High Mass with Tagged Protons in Proton-Proton Collisions at sqrt[s]=13 TeV

A search for exclusive two-photon production via photon exchange in proton-proton collisions, pp→pγγp with intact protons, is presented. The data correspond to an integrated luminosity of 9.4  fb^{-1} collected in 2016 using the CMS and TOTEM detectors at a center-of-mass energy of 13 TeV at the LHC. Events are selected with a diphoton invariant mass above 350 GeV and with both protons intact in the final state, to reduce backgrounds from strong interactions. The events of interest are those where the invariant mass and rapidity calculated from the momentum losses of the forward-moving protons match the mass and rapidity of the central, two-photon system. No events are found that satisfy this condition. Interpreting this result in an effective dimension-8 extension of the standard model, the first limits are set on the two anomalous four-photon coupling parameters. If the other parameter is constrained to its standard model value, the limits at 95% confidence level are |ζ_{1}|<2.9×10^{-13}  GeV^{-4} and |ζ_{2}|<6.0×10^{-13}  GeV^{-4}.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Observation of the B_{c}^{+} Meson in Pb-Pb and pp Collisions at sqrt[s_{NN}]=5.02 TeV and Measurement of its Nuclear Modification Factor

The B_{c}^{+} meson is observed for the first time in heavy ion collisions. Data from the CMS detector are used to study the production of the B_{c}^{+} meson in lead-lead (Pb-Pb) and proton-proton (pp) collisions at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=5.02  TeV, via the B_{c}^{+}→(J/ψ→μ^{+}μ^{-})μ^{+}ν_{μ} decay. The B_{c}^{+} nuclear modification factor, derived from the Pb-Pb-to-pp ratio of production cross sections, is measured in two bins of the trimuon transverse momentum and of the Pb-Pb collision centrality. The B_{c}^{+} meson is shown to be less suppressed than quarkonia and most of the open heavy-flavor mesons, suggesting that effects of the hot and dense nuclear matter created in heavy ion collisions contribute to its production. This measurement sets forth a promising new probe of the interplay of suppression and enhancement mechanisms in the production of heavy-flavor mesons in the quark-gluon plasma.

Hypertriton Production in p-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

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<y<0 for the 40% highest-multiplicity p-Pb collisions is dN/dy=[6.3±1.8(stat)±1.2(syst)]×10^{-7}. The measurement is compared with the expectations of statistical hadronization and coalescence models, which describe the nucleosynthesis in hadronic collisions. These two models predict very different yields of the hypertriton in charged particle multiplicity environments relevant to small collision systems such as p-Pb, and therefore the measurement of dN/dy is crucial to distinguish between them. The precision of this measurement leads to the exclusion with a significance larger than 6.9σ of some configurations of the statistical hadronization model, thus constraining the theory behind the production of loosely bound states at hadron colliders.

1052 CLINICAL MEDICATION REVIEWS AND OPTIMISATION FOR INPATIENTS IDENTIFIED AS FRAIL ON THE ELDERLY CARE WARDS AT EAST LANCASHIRE HEALTH TRUST

Introduction

Inpatient medication review occurs daily on our elderly wards and NICE (clinical guideline NG5) advocates using a Stopp/Start tool. Polypharmacy and tablet burden are common issues in frail patients and medications should be under regular review. Evidence of these reviews can be laborious to identify in written notes, particularly for frail patients with complex discharges. We aimed to determine whether clinical medication reviews are documented clearly at ELHT and to improve this.

Method

Patients with a Rockwood frailty score of ≥6 were identified and inpatient notes and charts audited for written detail of medication reviews and drug changes, then compared to the trust Stopp/Start toolkit. Cycle 1 was prior to intervention. We then delivered clinical education on medication optimisation and prompted use of ‘medications review’ proforma on existing trust documents. Cycle 2 occurred after this, then following changeover of junior doctors educational sessions were repeated and cycle 3 data collected.

Results

82% of all patients audited had altered medications with a mean hospital stay of 8 days. On cycle 1 65% of patients with altered medications had documentation to explain medication changes, on cycle 2 this improved to 88% and 72% on cycle 3. 92% of patients had a documented medication review (even if this involved no drug changes) at cycle 1 which improved to 100% on cycle 2 and remained at 92% on cycle 3. Both before and after intervention medications were appropriately rationalised or introduced.

Conclusion

We were already conducting regular reviews and optimising medications for frail patients. Prior to intervention there were inconsistencies on how this was documented. Through education and proforma for documentation this greatly improved, in turn improving communication and continuation of care on discharge. We are introducing electronic records to the trust and aim to include medication reviews into this system.

A proteomic atlas of atherosclerosis: regional proteomic signatures for plaque inflammation and calcification

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): This study was mainly supported from the British Heart Foundation (BHF) supporting Prof. Manuel Mayr as a Chair Holder (CH/16/3/32406) with BHF programme grant support (RG/16/14/32397) and Dr. Theofilatos with BHF programm grant support (G/20/10387).

Background

Using proteomics, we strove to reveal novel molecular subtypes of human atherosclerotic lesions, study their associations with histology and imaging and relate them to long-term cardiovascular outcomes.

Methods

219 samples were obtained from 120 patients undergoing carotid endarterectomy. Sequential protein extraction was combined with multiplexed, discovery proteomics. Parallel reaction monitoring for 135 proteins was deployed for targeted validation. A combination of statistical, bioinformatics and machine learning methods was used to perform differential expression, network, pathway enrichment analysis and train and evaluate prognostic models.

Results

Our extensive proteomics analysis from the core and periphery of plaques doubled the coverage of the plaque proteome compared to the largest proteomics study on atherosclerosis thus far. Plaque inflammation and calcification signatures were inversely correlated and validated with targeted proteomics. The inflammation signature was enriched with neutrophil-derived proteins, including calprotectin (S100A8/9) and myeloperoxidase. The calcification signature contained fetuin-A, osteopontin, and gamma-carboxylated proteins. Sex differences in the proteome of atherosclerosis were explained by a higher proportion of calcified plaques in women. Single-cell RNA sequencing data attributed the inflammation signature predominantly to neutrophils and macrophages and the calcification signature to smooth muscle cells, except for certain plasma proteins that were not expressed but retained in the plaque, i.e., fetuin-A. Echogenic lesions reflect the collagen content and calcification of plaque but carotid Duplex ultrasound fails to capture the extent of inflammatory protein changes in symptomatic plaques. Applying dimensionality reduction and machine learning on the proteomics data defined 4 distinct plaque phenotypes and revealed key protein signatures linked to smooth muscle cell content, plaque calcification and structural extracellular matrix, which improved the 9-year prognostic AUC by 25% compared to ultrasound and histology. A biosignature of four proteins (CNN1, PROC, SERPH, and CSPG2) independently predicted the progression of atherosclerosis and cardiovascular mortality with an AUC of 75%

Conclusion

We combined discovery and targeted proteomics with network reconstruction and clustering techniques to provide molecular insights into protein changes in atherosclerotic plaques. The application of proteomics and machine learning techniques revealed distinct clusters of plaques that inform on disease progression and future adverse cardiovascular events.

MicroRNA biomarkers of platelet function

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): British Heart Foundation (BHF), VASCage (Centre for Promoting Vascular Health in the Ageing Community) of the Austrian Research Promotion Agency FFG (COMET program - Competence Centers for Excellent Technologies)

Introduction

Antiplatelet therapy (APT) leads to reduced morbidity and mortality in patients with cardiovascular disease but some still have thrombotic events. Tailoring APT to platelet function is currently limited by a lack of suitable platelet function tests. It has been previously shown that different circulating microRNAs (miRNAs) are derived from platelets and their measurement could provide new markers of platelet reactivity.

Purpose

To compare the release of different platelet miRNAs in response to different platelet agonists.

Methods

Measurements of platelet function were performed by light transmission aggregometry (LTA) in participants of the 2015 follow-up of the Bruneck study (n=338), using the following agonists: arachidonic acid (1mM), adenosine diphosphate (5µM, 20µM), collagen (0.4 µg/ml, 4 µg/ml, 10µg/ml), TRAP-6 amide (25µM) and U46619 (10µM). LTA platelet releasates were then used for RT-qPCR measurements of five platelet-enriched miRNAs (miR-21, miR-126, miR-150, miR-197, miR-223). Platelet-poor plasma (PPP) served as negative control.

Results

Platelet activation led to aggregation and extracellular release of miRNAs, with aspirin users (n=155) showing significantly lower miRNA release than non-aspirin users (n=183). Agonist responsiveness differed among miRNAs, with miR-21 being hyperresponsive to arachidonic acid and miR-150 being hyperresponsive to adenosine diphosphate, whilst release of miR-126, miR-197 and miR-223 was strongest to collagen (10µg/ml). In non-aspirin users, inflammation markers such as granulocyte counts or C-reactive protein correlated positively with platelet-derived miRNAs measured in PPP, whilst they correlated negatively with platelet-derived miRNAs measured in releasates. These effects were absent in aspirin users.

Conclusions

MiRNAs released from activated platelets can be reliably detected in PPP and platelet releasates. Preferential release of miRNAs in response to specific agonists suggests a selective release mechanism. Elevated PPP levels and decreased releasate levels of platelet-derived miRNAs in inflammatory environments suggest platelet exhaustion ex vivo due to platelet pre-activation.

Polarization of Λ and Λ[over ¯] Hyperons along the Beam Direction in Pb-Pb Collisions at sqrt[s]_{NN}=5.02 TeV

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.

Search for low-mass dilepton resonances in Higgs boson decays to four-lepton final states in proton-proton collisions at s = 13 TeV

A search for low-mass dilepton resonances in Higgs boson decays is conducted in the four-lepton final state. The decay is assumed to proceed via a pair of beyond the standard model particles, or one such particle and a Z boson. The search uses proton-proton collision data collected with the CMS detector at the CERN LHC, corresponding to an integrated luminosity of 137 fb - 1 , at a center-of-mass energy s = 13 TeV . No significant deviation from the standard model expectation is observed. Upper limits at 95% confidence level are set on model-independent Higgs boson decay branching fractions. Additionally, limits on dark photon and axion-like particle production, based on two specific models, are reported.

Using Z Boson Events to Study Parton-Medium Interactions in Pb-Pb Collisions

The spectra measurements of charged hadrons produced in the shower of a parton originating in the same hard scattering with a leptonically decaying Z boson are reported in lead-lead nuclei (Pb-Pb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV. Both Pb-Pb and pp data sets are recorded by the CMS experiment at the LHC and correspond to an integrated luminosity of 1.7  nb^{-1} and 320  pb^{-1}, respectively. Hadronic collision data with one reconstructed Z boson candidate with the transverse momentum p_{T}>30  GeV/c are analyzed. The Z boson constrains the initial energy and direction of the associated parton. In heavy ion events, azimuthal angular distributions of charged hadrons with respect to the direction of a Z boson are sensitive to modifications of the in-medium parton shower and medium response. compared to reference data from pp interactions, the results for central Pb-Pb collisions indicate a modification of the angular correlations. The measurements of the fragmentation functions and p_{T} spectra of charged particles in Z boson events, which are sensitive to medium modifications of the parton shower longitudinal structure, are also reported. Significant modifications in central Pb-Pb events compared to the pp reference data are also found for these observables.

Measurement of the Groomed Jet Radius and Momentum Splitting Fraction in pp and Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

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.

Search for strongly interacting massive particles generating trackless jets in proton-proton collisions at s = 13 TeV

A search for dark matter in the form of strongly interacting massive particles (SIMPs) using the CMS detector at the LHC is presented. The SIMPs would be produced in pairs that manifest themselves as pairs of jets without tracks. The energy fraction of jets carried by charged particles is used as a key discriminator to suppress efficiently the large multijet background, and the remaining background is estimated directly from data. The search is performed using proton-proton collision data corresponding to an integrated luminosity of 16.1 fb - 1 , collected with the CMS detector in 2016. No significant excess of events is observed above the expected background. For the simplified dark matter model under consideration, SIMPs with masses up to 100 GeV are excluded and further sensitivity is explored towards higher masses.

Measurement of the Inclusive and Differential Higgs Boson Production Cross Sections in the Decay Mode to a Pair of τ Leptons in pp Collisions at sqrt[s]=13 TeV

Measurements of the inclusive and differential fiducial cross sections of the Higgs boson are presented, using the τ lepton decay channel. The differential cross sections are measured as functions of the Higgs boson transverse momentum, jet multiplicity, and transverse momentum of the leading jet in the event, if any. The analysis is performed using proton-proton collision data collected with the CMS detector at the LHC at a center-of-mass energy of 13  TeV and corresponding to an integrated luminosity of 138  fb^{-1}. These are the first differential measurements of the Higgs boson cross section in the final state of two τ leptons. In final states with a large jet multiplicity or with a Lorentz-boosted Higgs boson, these measurements constitute a significant improvement over measurements performed in other final states.

Search for long-lived particles decaying to leptons with large impact parameter in proton-proton collisions at s = 13 Te

A search for new long-lived particles decaying to leptons using proton-proton collision data produced by the CERN LHC at s = 13 Te is presented. Events are selected with two leptons (an electron and a muon, two electrons, or two muons) that both have transverse impact parameter values between 0.01 and 10 cm and are not required to form a common vertex. Data used for the analysis were collected with the CMS detector in 2016, 2017, and 2018, and correspond to an integrated luminosity of 118 (113) fb - 1 in the e e channel ( e μ and μ μ channels). The search is designed to be sensitive to a wide range of models with displaced e μ , e e , and μ μ final states. The results constrain several well-motivated models involving new long-lived particles that decay to displaced leptons. For some areas of the available phase space, these are the most stringent constraints to date.

Evidence for X(3872) in Pb-Pb Collisions and Studies of its Prompt Production at sqrt[s_{NN}]=5.02 TeV

The first evidence for X(3872) production in relativistic heavy ion collisions is reported. The X(3872) production is studied in lead-lead (Pb-Pb) collisions at a center-of-mass energy of sqrt[s_{NN}]=5.02  TeV per nucleon pair, using the decay chain X(3872)→J/ψπ^{+}π^{-}→μ^{+}μ^{-}π^{+}π^{-}. The data were recorded with the CMS detector in 2018 and correspond to an integrated luminosity of 1.7  nb^{-1}. The measurement is performed in the rapidity and transverse momentum ranges |y|<1.6 and 15<p_{T}<50  GeV/c. The significance of the inclusive X(3872) signal is 4.2 standard deviations. The prompt X(3872) to ψ2S yield ratio is found to be ρ^{Pb-Pb}=1.08±0.49(stat)±0.52(syst), to be compared with typical values of 0.1 for pp collisions. This result provides a unique experimental input to theoretical models of the X(3872) production mechanism, and of the nature of this exotic state.

Measurement of Prompt D^{0}, Λ_{c}^{+}, and Σ_{c}^{0,++}(2455) Production in Proton-Proton Collisions at sqrt[s]=13 TeV

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<p_{T}<12 and 1<p_{T}<24  GeV/c. Values significantly larger than in e^{+}e^{-} collisions are observed, indicating for the first time that baryon enhancement in hadronic collisions also extends to the Σ_{c}. The feed-down contribution to Λ_{c}^{+} production from Σ_{c}^{0,+,++} is also reported and is found to be larger than in e^{+}e^{-} collisions. The data are compared with predictions from event generators and other phenomenological models, providing a sensitive test of the different charm-hadronization mechanisms implemented in the models.

Vitamin D supplementation and clinical outcomes in COVID-19: a systematic review and meta-analysis

PURPOSE

To provide a precise summary and collate the hitherto available clinical evidence on the effect of vitamin D supplementation on clinical outcomes in COVID-19 patients.

METHODS

PubMed/MEDLINE, Scopus, and Web of Science databases were systematically searched using appropriate keywords till June 8, 2021, to identify observational studies and randomized controlled trials (RCTs) reporting adverse clinical outcomes (ICU admission and/or mortality) in COVID-19 patients receiving vitamin D supplementation vs. those not receiving the same. Both prior use and use of vitamin D after COVID-19 diagnosis were considered. Unadjusted/adjusted pooled odds ratio (OR) with 95% confidence intervals (CI) were calculated (PROSPERO registration number CRD42021248488).

RESULTS

We identified 13 studies (10 observational, 3 RCTs) pooling data retrieved from 2933 COVID-19 patients. Pooled analysis of unadjusted data showed that vitamin D use in COVID-19 was significantly associated with reduced ICU admission/mortality (OR 0.41, 95% CI: 0.20, 0.81, p = 0.01, I2 = 66%, random-effects model). Similarly, on pooling adjusted risk estimates, vitamin D was also found to reduce the risk of adverse outcomes (pooled OR 0.27, 95% CI: 0.08, 0.91, p = 0.03, I2 = 80%, random-effects model). Subgroup analysis showed that vitamin D supplementation was associated with improved clinical outcomes only in patients receiving the drug post-COVID-19 diagnosis and not in those who had received vitamin D before diagnosis.

CONCLUSIONS

Vitamin D supplementation might be associated with improved clinical outcomes, especially when administered after the diagnosis of COVID-19. However, issues regarding the appropriate dose, duration, and mode of administration of vitamin D remain unanswered and need further research.

Measurement of the Cross Sections of Ξ_{c}^{0} and Ξ_{c}^{+} Baryons and of the Branching-Fraction Ratio BR(Ξ_{c}^{0}→Ξ^{-}e^{+}ν_{e})/BR(Ξ_{c}^{0}→Ξ^{-}π^{+}) in pp Collisions at sqrt[s]=13 TeV

The p_{T}-differential cross sections of prompt charm-strange baryons Ξ_{c}^{0} and Ξ_{c}^{+} were measured at midrapidity (|y|<0.5) in proton-proton (pp) collisions at a center-of-mass energy sqrt[s]=13  TeV with the ALICE detector at the LHC. The Ξ_{c}^{0} baryon was reconstructed via both the semileptonic decay (Ξ^{-}e^{+}ν_{e}) and the hadronic decay (Ξ^{-}π^{+}) channels. The Ξ_{c}^{+} baryon was reconstructed via the hadronic decay (Ξ^{-}π^{+}π^{+}) channel. The branching-fraction ratio BR(Ξ_{c}^{0}→Ξ^{-}e^{+}ν_{e})/BR(Ξ_{c}^{0}→Ξ^{-}π^{+})=1.38±0.14(stat)±0.22(syst) was measured with a total uncertainty reduced by a factor of about 3 with respect to the current world average reported by the Particle Data Group. The transverse momentum (p_{T}) dependence of the Ξ_{c}^{0}- and Ξ_{c}^{+}-baryon production relative to the D^{0} meson and to the Σ_{c}^{0,+,++}- and Λ_{c}^{+}-baryon production are reported. The baryon-to-meson ratio increases toward low p_{T} up to a value of approximately 0.3. The measurements are compared with various models that take different hadronization mechanisms into consideration. The results provide stringent constraints to these theoretical calculations and additional evidence that different processes are involved in charm hadronization in electron-positron (e^{+}e^{-}) and hadronic collisions.

Search for Long-Lived Particles Decaying in the CMS End Cap Muon Detectors in Proton-Proton Collisions at sqrt[s]=13 TeV

A search for long-lived particles (LLPs) produced in decays of standard model (SM) Higgs bosons is presented. The data sample consists of 137  fb^{-1} of proton-proton collisions at sqrt[s]=13  TeV, recorded at the LHC in 2016-2018. A novel technique is employed to reconstruct decays of LLPs in the end cap muon detectors. The search is sensitive to a broad range of LLP decay modes and to masses as low as a few GeV. No excess of events above the SM background is observed. The most stringent limits to date on the branching fraction of the Higgs boson to LLPs subsequently decaying to quarks and τ^{+}τ^{-} are found for proper decay lengths greater than 6, 20, and 40 m, for LLP masses of 7, 15, and 40 GeV, respectively.

Λ_{c}^{+} Production and Baryon-to-Meson Ratios in pp and p-Pb Collisions at sqrt[s_{NN}]=5.02 TeV at the LHC

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<p_{T}<12  GeV/c, exhibiting similarities with the light-flavor baryon-to-meson ratios p/π and Λ/K_{S}^{0}. At low p_{T}, predictions that include additional color-reconnection mechanisms beyond the leading-color approximation, assume the existence of additional higher-mass charm-baryon states, or include hadronization via coalescence can describe the data, while predictions driven by charm-quark fragmentation processes measured in e^{+}e^{-} and e^{-}p collisions significantly underestimate the data. The results presented in this Letter provide significant evidence that the established assumption of universality (colliding-system independence) of parton-to-hadron fragmentation is not sufficient to describe charm-baryon production in hadronic collisions at LHC energies.

Measurements of the Electroweak Diboson Production Cross Sections in Proton-Proton Collisions at sqrt[s]=5.02 TeV Using Leptonic Decays

The first measurements of diboson production cross sections in proton-proton interactions at a center-of-mass energy of 5.02 TeV are reported. They are based on data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 302  pb^{-1}. Events with two, three, or four charged light leptons (electrons or muons) in the final state are analyzed. The WW, WZ, and ZZ total cross sections are measured as σ_{WW}=37.0_{-5.2}^{+5.5}(stat)_{-2.6}^{+2.7}(syst)  pb, σ_{WZ}=6.4_{-2.1}^{+2.5}(stat)_{-0.3}^{+0.5}(syst)  pb, and σ_{ZZ}=5.3_{-2.1}^{+2.5}(stat)_{-0.4}^{+0.5}(syst)  pb. All measurements are in good agreement with theoretical calculations at combined next-to-next-to-leading order quantum chromodynamics and next-to-leading order electroweak accuracy.