RIB induced reactions: Studying astrophysical reactions with low-energy RI beam at CRIB

Astrophysical reactions involving radioactive isotopes (RI) often play an important role in high-temperature stellar environments. The experimental studies on the reaction rates for those are still limited mainly due to the technical difficulties in producing high-quality RI beams. A direct measurement of those reactions would be still challenging in many cases, however, we can make a reliable evaluation of the reaction rates by an indirect method or by studying the resonance prorerties. Here we ntroduce recent examples of experimental studies on such RI-involving astrophysical reactions, performed at Center for Nuclear Study, the University of Tokyo, using the low-energy RI beam separator CRIB. One is for the neutron-induced destruction reactions of 7Be in the Big-Bang nucleosynthesis, and the other is the study on the 22Mg(α, p) reaction relevant in X-ray bursts, which was performed with the resonant scattering method from the inverse reaction channel.

Pain, Analgesic Use, and Patient Satisfaction With Spinal Versus General Anesthesia for Hip Fracture Surgery : A Randomized Clinical Trial

BACKGROUND

The REGAIN (Regional versus General Anesthesia for Promoting Independence after Hip Fracture) trial found similar ambulation and survival at 60 days with spinal versus general anesthesia for hip fracture surgery. Trial outcomes evaluating pain, prescription analgesic use, and patient satisfaction have not yet been reported.

OBJECTIVE

To compare pain, analgesic use, and satisfaction after hip fracture surgery with spinal versus general anesthesia.

DESIGN

Preplanned secondary analysis of a pragmatic randomized trial. (ClinicalTrials.gov: NCT02507505).

SETTING

46 U.S. and Canadian hospitals.

PARTICIPANTS

Patients aged 50 years or older undergoing hip fracture surgery.

INTERVENTION

Spinal or general anesthesia.

MEASUREMENTS

Pain on postoperative days 1 through 3; 60-, 180-, and 365-day pain and prescription analgesic use; and satisfaction with care.

RESULTS

A total of 1600 patients were enrolled. The average age was 78 years, and 77% were women. A total of 73.5% (1050 of 1428) of patients reported severe pain during the first 24 hours after surgery. Worst pain over the first 24 hours after surgery was greater with spinal anesthesia (rated from 0 [no pain] to 10 [worst pain imaginable]; mean difference, 0.40 [95% CI, 0.12 to 0.68]). Pain did not differ across groups at other time points. Prescription analgesic use at 60 days occurred in 25% (141 of 563) and 18.8% (108 of 574) of patients assigned to spinal and general anesthesia, respectively (relative risk, 1.33 [CI, 1.06 to 1.65]). Satisfaction was similar across groups.

LIMITATION

Missing outcome data and multiple outcomes assessed.

CONCLUSION

Severe pain is common after hip fracture. Spinal anesthesia was associated with more pain in the first 24 hours after surgery and more prescription analgesic use at 60 days compared with general anesthesia.

PRIMARY FUNDING SOURCE

Patient-Centered Outcomes Research Institute.

Estimating the Nosocomial Transmission Rate of COVID-19 in Orthopaedic Surgery Patients During the Peak of the Pandemic

Purpose

To estimate the risk of hospital-acquired COVID-19 transmission in a population of orthopaedic trauma patients during the first wave of the pandemic.

Patients and Methods

This is a retrospective cohort study of 109 patients who underwent an emergent orthopedic procedure by a single orthopedic traumatologist between March 1, 2020 and May 15, 2020 during the first peak of the pandemic. After applying inclusion and exclusion criteria, a total of 82 patients (67 inpatients and 15 ambulatory) were identified for final analysis. The primary outcome measured was postoperative Coronavirus (COVID-19) status. Secondary outcome measures included length of stay and discharge disposition.

Results

The mean age and length of stay in the hospital group was 59.5 years (± 21.7) and 4.3 days (± 4.6), respectively, versus 47.9 years (± 9.8) in the ambulatory group. 7.3% (6/82) of the inpatients subsequently tested or screened positive for COVID-19 at 2 weeks post-operatively, compared to 0/15 ambulatory patients (P=0.58). Of the 6 inpatients who tested positive, 4 (66.7%) were discharged to a rehabilitation center. Diabetes (P=0.05), hypertension (P=0.02), and congestive heart failure (P=0.005) were associated with transmission.

Conclusion

In this analysis, there was a nosocomial transmission rate of 7% compared to zero in the ambulatory surgery center, however this was not found to be statistically significant. This data supports the use of precautions such as frequent screening, hand washing, and masks to reduce transmission when COVID-19 rates are high. There is a lower risk of nosocomial COVID-19 transmission for patients treated as an outpatient and elective surgical procedures may be safer in this setting.

Experimental studies on astrophysical reactions at the low-energy RI beam separator CRIB

Experimental studies on astrophysical reactions involving radioactive isotopes (RI) often accompany technical challenges. Studies on such nuclear reactions have been conducted at the low-energy RI beam separator CRIB, operated by Center for Nuclear Study, the University of Tokyo. We discuss two cases of astrophysical reaction studies at CRIB; one is for the 7Be+n reactions which may affect the primordial 7Li abundance in the Big-Bang nucleosynthesis, and the other is for the 22Mg(α, p) reaction relevantin X-raybursts.

The effect of hutch compass direction on primary heat stress responses in dairy calves in a continental region

Heat stress reduction in hutch-reared dairy calves is overlooked on most dairy farms. We hypothesised that during summer, the microclimate within hutches is directly affected by compass direction as a result of differences in exposure to solar radiation. On a bright, midAugust day a number of behavioural and physiological heat stress response measures (respiratory rate, body posture, being in the shade or sun) were recorded in 20-min intervals from 0720–1900h on calves housed in hutches with entrances facing all four points of the compass. In conjunction with this, dry bulb (ambient) and black globe temperatures, and wind speed were recorded both inside the plastic hutches and at one sunny site at the exterior. Data were compared in terms of distinct periods of the day (0720–1100, 1120– 1500, 1520–1900h). Dry bulb temperatures were higher inside hutches compared to outside while for black globe temperatures the opposite was true. Daily average temperatures and respiratory rates did not differ between hutches facing different compass points. In the morning and afternoon, hutch temperature and calf respiratory rate differed relative to compass point. Calves in east- and northfacing hutches were seen more in the shade than those in south- and west-facing ones. Our conclusion was that in a continental region having hutch entrances face towards the east or north confers some advantages in mitigating severe solar heat load in summer.

[Use of synthetic slings and mesh implants in the treatment of female stress urinary incontinence and prolapse : Statement of the Working Group on Urological Functional Diagnostics and Female Urology of the Academy of the German Society of Urology]

Due to a safety alert issued by the US Food and Drug Administration (FDA) in 2011 for transvaginal mesh implants to treat female prolapse as a result of numerous reports of complications such as infection, chronic pain, dyspareunia, vaginal erosion, shrinkage and erosion into other organs nearly all industrial products have been withdrawn from the market in the meantime. The United Kingdom, Australia, and New Zealand extended warnings and prohibitions even on the implantation of midurethral slings (TVT, TOT). In view of these current international controversies regarding the use of implanted materials for the treatment of stress incontinence and prolapse and the lack of clear guidelines for the use of biomaterials, the opinion of the Working Group on Urological Functional Diagnostics and Female Urology should provide clarity. The Opinion is based on the SCENIHR Report of the "European Commission's Scientific Committee on Emerging and Newly Identified Health Risks", the "Consensus Statement of the European Urology Association and the European Urogynaecological Association on the Use of Implanted Materials for Treating Pelvic Organ Prolapse and Stress Urinary Incontinence" and in compliance with relevant EAU and national guidelines and the opinion of the Association for Urogynaecology and Plastic Pelvic Floor Reconstruction (AGUB eV). In addition, recommendations are given for the future handling of implants of slings and meshes for the treatment of stress incontinence and prolapse from a urologic viewpoint.

Effectiveness of P6 Stimulation for Reduction of Nausea and Vomiting During Caesarean Section Under Combined Spinal-Epidural Anaesthesia: A Randomised Controlled Trial

Objective

Obstetric patients who receive combined spinal-epidural (CSE) anaesthesia for elective caesarean section (CS) frequently experience intraoperative nausea and vomiting (N&V). Prophylactic therapy with antiemetic agents can have multiple adverse effects to the mother and baby. We designed a randomised clinical trial to evaluate the efficacy of electrical P6 stimulation for prophylactic N&V treatment for scheduled elective CS performed under CSE anaesthesia.

Methods

Following the Institutional Review Board approval and informed consent, a total of 180 patients were randomly allocated into three groups: (1) P6 stimulation (via a peripheral nerve stimulator), (2) intravenous (IV) antiemetics (metoclopramide and ondansetron), and (3) control (no IV antiemetic medications and no P6 stimulation), with 60 parturients in each group.

Results

Significantly fewer patients experienced intraoperative N&V in the P6 group (nausea 36.7% and vomiting 13.3%) and IV antiemetic group (nausea 23.3% and vomiting 16.7%) than those in the control group (nausea 73.3% and vomiting 45%; p<0.001). In addition, significantly fewer patients required rescue antiemetic medications in the P6 group (35%) and the IV antiemetic group (31.7%) than those in the control group (73.3%; p<0.001). There was no significant difference in the overall anaesthetic care satisfaction reported between the three study groups.

Conclusion

Our data suggest that P6 stimulation is as simple and as effective as our routine prophylactic IV antiemetic treatment for prevention of N&V during CS performed under CSE anaesthesia that could be of great interest to patients and obstetric anaesthesiologists who prefer treatments with fewer potential side effects.

Daclatasvir and Sofosbuvir With or Without Ribavirin in Liver Transplant Recipients: A Single-Center Real-World Study

BACKGROUND

Treatment with direct-acting antiviral drugs in interferon-free regimens is currently recommended for viral hepatitis C recurrence after liver transplantation. There are limited data regarding its results in this population, and no optimal treatment scheme has yet been singled out.

METHODS

We report our real-world results in liver transplant (LT) recipients. All patients were hepatitis C virus (HCV) monoinfected and completed a 12-week treatment course, followed 12 weeks later by HCV polymerase chain reaction testing with 12 IU/mL sensibility. Liver fibrosis was graded with the use of biopsies taken <12 months before treatment and stratified as early (0-1) or moderate to advanced (2-4) according to the Metavir score.

RESULTS

Median postoperative time was 5.2 years. Genotype 3 was found in 66.7% of the sample. The following regimens were prescribed: daclatasvir-sofosbuvir with (n = 11) or without (n = 28) ribavirin. Genotypes 1 and 3 were evenly distributed between the regimens. Sustained virologic response (SVR) was obtained in 24 out of 28 patients (85.7%) who received daclatasvir-sofosbuvir and in all patients (100%) who received daclatasvir-sofosbuvir-ribavirin (global SVR 89.7%). All patients that failed treatment had genotype 3 HCV. Fibrosis was evaluated in 79.5% of the sample: 48.4% had early and 51.6% had moderate to advanced fibrosis, for which ribavirin was more commonly prescribed (P = .001).

CONCLUSIONS

The SVR rate in our LT recipients was similar to that previously reported in the literature. The addition of ribavirin to DAA treatment appears to be justified in this population.

Management of Portal Hypertension After Liver Transplantation

INTRODUCTION

Post-transplantation portal hypertension has severe complications, such as esophageal varix bleeding, therapy refractory ascites, extreme splenomegaly, and graft dysfunction. The aim of our study was to analyze the effectiveness of the therapeutic strategies and how to visualize the procedure.

METHODS

A retrospective study involving liver transplantation patients from the Semmelweis University Department of Transplantation and Surgery was performed between 2005 and 2015. The prevalence, etiology, and leading complications of the condition were determined. The applied interventions' effects on the patients' ascites volume, splenic volume, and the occurrence of variceal bleeding were determined. Mean portal blood flow velocity and congestion index values were calculated using Doppler ultrasonography.

RESULTS

The prevalence of post-transplantation portal hypertension requiring intervention was 2.8%. The most common etiology of the disease was portal anastomotic stenosis. The most common complications were esophageal varix bleeding and therapy refractory ascites. The patients' ascites volume decreased significantly (2923.3 ± 1893.2 mL vs. 423.3 ± 634.3 mL; P < .05), their splenic volume decreased markedly. After the interventions, only one case of recurrent variceal bleeding was reported. The calculated Doppler parameters were altered in the opposite direction in cases of pre-hepatic versus intra- or post-hepatic portal hypertension. After the interventions, these parameters shifted towards the physiologic ranges.

CONCLUSION

The interventions performed in our clinic were effective in most cases. The patients' ascites volume, splenic volume, and the prevalence of variceal bleeding decreased after the treatment. Doppler ultrasonography has proved to be a valuable imaging modality in the diagnosis and the follow-up of post-transplantation portal hypertension.

D-Meson Azimuthal Anisotropy in Midcentral Pb-Pb Collisions at sqrt[s]_{NN}=5.02 TeV

The azimuthal anisotropy coefficient v_{2} of prompt D^{0}, D^{+}, D^{*+}, and D_{s}^{+} mesons was measured in midcentral (30%-50% centrality class) Pb-Pb collisions at a center-of-mass energy per nucleon pair sqrt[s_{NN}]=5.02  TeV, with the ALICE detector at the LHC. The D mesons were reconstructed via their hadronic decays at midrapidity, |y|<0.8, in the transverse momentum interval 1<p_{T}<24  GeV/c. The measured D-meson v_{2} has similar values as that of charged pions. The D_{s}^{+} v_{2}, measured for the first time, is found to be compatible with that of nonstrange D mesons. The measurements are compared with theoretical calculations of charm-quark transport in a hydrodynamically expanding medium and have the potential to constrain medium parameters.

J/ψ Elliptic Flow in Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

We report a precise measurement of the J/ψ elliptic flow in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV with the ALICE detector at the LHC. The J/ψ mesons are reconstructed at midrapidity (|y|<0.9) in the dielectron decay channel and at forward rapidity (2.5<y<4.0) in the dimuon channel, both down to zero transverse momentum. At forward rapidity, the elliptic flow v_{2} of the J/ψ is studied as a function of the transverse momentum and centrality. A positive v_{2} is observed in the transverse momentum range 2<p_{T}<8  GeV/c in the three centrality classes studied and confirms with higher statistics our earlier results at sqrt[s_{NN}]=2.76  TeV in semicentral collisions. At midrapidity, the J/ψ  v_{2} is investigated as a function of the transverse momentum in semicentral collisions and found to be in agreement with the measurements at forward rapidity. These results are compared to transport model calculations. The comparison supports the idea that at low p_{T} the elliptic flow of the J/ψ originates from the thermalization of charm quarks in the deconfined medium but suggests that additional mechanisms might be missing in the models.

Anomalous Evolution of the Near-Side Jet Peak Shape in Pb-Pb Collisions at sqrt[s_{NN}]=2.76 TeV

The measurement of two-particle angular correlations is a powerful tool to study jet quenching in a p_{T} region inaccessible by direct jet identification. In these measurements pseudorapidity (Δη) and azimuthal (Δφ) differences are used to extract the shape of the near-side peak formed by particles associated with a higher p_{T} trigger particle (1<p_{T,trig}<8  GeV/c). A combined fit of the near-side peak and long-range correlations is applied to the data allowing the extraction of the centrality evolution of the peak shape in Pb-Pb collisions at sqrt[s_{NN}]=2.76  TeV. A significant broadening of the peak in the Δη direction at low p_{T} is found from peripheral to central collisions, which vanishes above 4  GeV/c, while in the Δφ direction the peak is almost independent of centrality. For the 10% most central collisions and 1<p_{T,assoc}<2  GeV/c, 1<p_{T,trig}<3  GeV/c a novel feature is observed: a depletion develops around the center of the peak. The results are compared to pp collisions at the same center of mass energy and ampt model simulations. The comparison to the investigated models suggests that the broadening and the development of the depletion is connected to the strength of radial and longitudinal flow.

Energy dependence of forward-rapidity [Formula: see text] and [Formula: see text] production in pp collisions at the LHC

We present results on transverse momentum ([Formula: see text]) and rapidity ([Formula: see text]) differential production cross sections, mean transverse momentum and mean transverse momentum square of inclusive [Formula: see text] and [Formula: see text] at forward rapidity ([Formula: see text]) as well as [Formula: see text]-to-[Formula: see text] cross section ratios. These quantities are measured in pp collisions at center of mass energies [Formula: see text] and 13 TeV with the ALICE detector. Both charmonium states are reconstructed in the dimuon decay channel, using the muon spectrometer. A comprehensive comparison to inclusive charmonium cross sections measured at [Formula: see text], 7 and 8 TeV is performed. A comparison to non-relativistic quantum chromodynamics and fixed-order next-to-leading logarithm calculations, which describe prompt and non-prompt charmonium production respectively, is also presented. A good description of the data is obtained over the full [Formula: see text] range, provided that both contributions are summed. In particular, it is found that for [Formula: see text] GeV/c the non-prompt contribution reaches up to 50% of the total charmonium yield.

Production of Σ(1385)± and Ξ(1530)0 in p-Pb collisions at sNN=5.02 TeV

The transverse momentum distributions of the strange and double-strange hyperon resonances (Σ ( 1385 ) ± , Ξ ( 1530 ) 0 ) produced in p-Pb collisions at s NN = 5.02 TeV were measured in the rapidity range - 0.5 < y CMS < 0 for event classes corresponding to different charged-particle multiplicity densities, ⟨ dN ch /dη lab ⟩ . The mean transverse momentum values are presented as a function of ⟨ dN ch /dη lab ⟩ , as well as a function of the particle masses and compared with previous results on hyperon production. The integrated yield ratios of excited to ground-state hyperons are constant as a function of ⟨ dN ch /dη lab ⟩ . The equivalent ratios to pions exhibit an increase with ⟨ dN ch /dη lab ⟩ , depending on their strangeness content.

Production of [Formula: see text] and [Formula: see text] mesons up to high transverse momentum in pp collisions at 2.76 TeV

The invariant differential cross sections for inclusive [Formula: see text] and [Formula: see text] mesons at midrapidity were measured in pp collisions at [Formula: see text] TeV for transverse momenta [Formula: see text] GeV/c and [Formula: see text] GeV/c, respectively, using the ALICE detector. This large range in [Formula: see text] was achieved by combining various analysis techniques and different triggers involving the electromagnetic calorimeter (EMCal). In particular, a new single-cluster, shower-shape based method was developed for the identification of high-[Formula: see text] neutral pions, which exploits that the showers originating from their decay photons overlap in the EMCal. Above 4 GeV/[Formula: see text], the measured cross sections are found to exhibit a similar power-law behavior with an exponent of about 6.3. Next-to-leading-order perturbative QCD calculations differ from the measured cross sections by about 30% for the [Formula: see text], and between 30-50% for the [Formula: see text] meson, while generator-level simulations with PYTHIA 8.2 describe the data to better than 10-30%, except at [Formula: see text] GeV/[Formula: see text]. The new data can therefore be used to further improve the theoretical description of [Formula: see text] and [Formula: see text] meson production.

Flow Dominance and Factorization of Transverse Momentum Correlations in Pb-Pb Collisions at the LHC

We present the first measurement of the two-particle transverse momentum differential correlation function, P_{2}≡⟨Δp_{T}Δp_{T}⟩/⟨p_{T}⟩^{2}, in Pb-Pb collisions at sqrt[s_{NN}]=2.76  TeV. Results for P_{2} are reported as a function of the relative pseudorapidity (Δη) and azimuthal angle (Δφ) between two particles for different collision centralities. The Δϕ dependence is found to be largely independent of Δη for |Δη|≥0.9. In the 5% most central Pb-Pb collisions, the two-particle transverse momentum correlation function exhibits a clear double-hump structure around Δφ=π (i.e., on the away side), which is not observed in number correlations in the same centrality range, and thus provides an indication of the dominance of triangular flow in this collision centrality. Fourier decompositions of P_{2}, studied as a function of the collision centrality, show that correlations at |Δη|≥0.9 can be well reproduced by a flow ansatz based on the notion that measured transverse momentum correlations are strictly determined by the collective motion of the system.

Measurement of azimuthal correlations of D mesons with charged particles in pp collisions at [Formula: see text] TeV and p-Pb collisions at [Formula: see text] TeV

The azimuthal correlations of D mesons with charged particles were measured with the ALICE apparatus in pp collisions at [Formula: see text] and p-Pb collisions at [Formula: see text] at the Large Hadron Collider. [Formula: see text], [Formula: see text], and [Formula: see text] mesons and their charge conjugates with transverse momentum [Formula: see text] and rapidity in the nucleon-nucleon centre-of-mass system [Formula: see text] (pp collisions) and [Formula: see text] (p-Pb collisions) were correlated to charged particles with [Formula: see text]. The yield of charged particles in the correlation peak induced by the jet containing the D meson and the peak width are compatible within uncertainties in the two collision systems. The data are described within uncertainties by Monte-Carlo simulations based on PYTHIA, POWHEG, and EPOS 3 event generators.

Biodegradable airway stents in infants - Potential life-threatening pitfalls

OBJECTIVE

The solution of severe tracheobronchial obstructions in early childhood means a great challenge. Biodegradable stents were intended to be a minimally invasive temporary solution which may decrease the number of interventions and limit the possible complications of stenting procedures. However, our first experiences have brought out a new, - especially in childhood - potentially life-threatening complication of this concept.

METHODS

Five SX-ELLA biodegradable polydioxanone stents was applied in three patients because of severe tracheobronchial obstruction: congenital tracheomalacia (7 day-old), acquired tracheomalacia (10 month-old), and congenital trachea-bronchomalacia (10 month-old).

RESULTS

The breathing of all children improved right after the procedure. We observed degradation of the stent from the 5th postoperative week which resulted in large intraluminar fragments causing significant airway obstruction: one patient died of severe pneumonia, the other baby required urgent bronchoscopy to remove the obstructing 'foreign body' from the trachea. In the third case repeated stent placements successfully maintained the tracheal lumen.

CONCLUSIONS

Polydioxanone stents may offer an alternative to metallic or silastic stents for collapse or external compression of the trachea in children; however, large decaying fragments mean a potential risk especially in the small size pediatric airway. The fragmentation of the stent, which generally starts in the 4-6 postoperative weeks, may create large sharp pieces. These may be anchored to the mucosa and covered by crust leading to obstruction. As repeated interventions are required, we do not consider the application of biodegradable stents unambiguously advantageous.

Correlated Event-by-Event Fluctuations of Flow Harmonics in Pb-Pb Collisions at sqrt[s_{NN}]=2.76 TeV

We report the measurements of correlations between event-by-event fluctuations of amplitudes of anisotropic flow harmonics in nucleus-nucleus collisions, obtained for the first time using a new analysis method based on multiparticle cumulants in mixed harmonics. This novel method is robust against systematic biases originating from nonflow effects and by construction any dependence on symmetry planes is eliminated. We demonstrate that correlations of flow harmonics exhibit a better sensitivity to medium properties than the individual flow harmonics. The new measurements are performed in Pb-Pb collisions at the center-of-mass energy per nucleon pair of sqrt[s_{NN}]=2.76  TeV by the ALICE experiment at the Large Hadron Collider. The centrality dependence of correlation between event-by-event fluctuations of the elliptic v_{2} and quadrangular v_{4} flow harmonics, as well as of anticorrelation between v_{2} and triangular v_{3} flow harmonics are presented. The results cover two different regimes of the initial state configurations: geometry dominated (in midcentral collisions) and fluctuation dominated (in the most central collisions). Comparisons are made to predictions from Monte Carlo Glauber, viscous hydrodynamics, ampt, and hijing models. Together with the existing measurements of the individual flow harmonics the presented results provide further constraints on the initial conditions and the transport properties of the system produced in heavy-ion collisions.

Centrality Dependence of the Charged-Particle Multiplicity Density at Midrapidity in Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

The pseudorapidity density of charged particles, dN_{ch}/dη, at midrapidity in Pb-Pb collisions has been measured at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=5.02  TeV. For the 5% most central collisions, we measure a value of 1943±54. The rise in dN_{ch}/dη as a function of sqrt[s_{NN}] is steeper than that observed in proton-proton collisions and follows the trend established by measurements at lower energy. The increase of dN_{ch}/dη as a function of the average number of participant nucleons, ⟨N_{part}⟩, calculated in a Glauber model, is compared with the previous measurement at sqrt[s_{NN}]=2.76  TeV. A constant factor of about 1.2 describes the increase in dN_{ch}/dη from sqrt[s_{NN}]=2.76 to 5.02 TeV for all centrality classes, within the measured range of 0%-80% centrality. The results are also compared to models based on different mechanisms for particle production in nuclear collisions.

Measurement of an Excess in the Yield of J/ψ at Very Low p_{T} in Pb-Pb Collisions at sqrt[s]_{NN}=2.76 TeV

We report on the first measurement of an excess in the yield of J/ψ at very low transverse momentum (p_{T}<0.3  GeV/c) in peripheral hadronic Pb-Pb collisions at sqrt[s_{NN}]=2.76  TeV, performed by ALICE at the CERN LHC. Remarkably, the measured nuclear modification factor of J/ψ in the rapidity range 2.5<y<4 reaches about 7 (2) in the p_{T} range 0-0.3  GeV/c in the 70%-90% (50%-70%) centrality class. The J/ψ production cross section associated with the observed excess is obtained under the hypothesis that coherent photoproduction of J/ψ is the underlying physics mechanism. If confirmed, the observation of J/ψ coherent photoproduction in Pb-Pb collisions at impact parameters smaller than twice the nuclear radius opens new theoretical and experimental challenges and opportunities. In particular, coherent photoproduction accompanying hadronic collisions may provide insight into the dynamics of photoproduction and nuclear reactions, as well as become a novel probe of the quark-gluon plasma.

Centrality dependence of charged jet production in p-Pb collisions at [Formula: see text] = 5.02 TeV

Measurements of charged jet production as a function of centrality are presented for  p-Pb  collisions recorded at [Formula: see text] TeV with the ALICE detector. Centrality classes are determined via the energy deposit in neutron calorimeters at zero degree, close to the beam direction, to minimise dynamical biases of the selection. The corresponding number of participants or binary nucleon-nucleon collisions is determined based on the particle production in the Pb-going rapidity region. Jets have been reconstructed in the central rapidity region from charged particles with the anti-[Formula: see text] algorithm for resolution parameters [Formula: see text] and [Formula: see text] in the transverse momentum range 20 to 120 GeV/c. The reconstructed jet momentum and yields have been corrected for detector effects and underlying-event background. In the five centrality bins considered, the charged jet production in  p-Pb   collisions is consistent with the production expected from binary scaling from pp collisions. The ratio of jet yields reconstructed with the two different resolution parameters is also independent of the centrality selection, demonstrating the absence of major modifications of the radial jet structure in the reported centrality classes.

Production of K[Formula: see text](892)[Formula: see text] and [Formula: see text](1020) in p-Pb collisions at [Formula: see text] = 5.02 TeV

The production of K[Formula: see text](892)[Formula: see text] and [Formula: see text](1020) mesons has been measured in p-Pb collisions at [Formula: see text][Formula: see text] 5.02 TeV. K[Formula: see text] and [Formula: see text] are reconstructed via their decay into charged hadrons with the ALICE detector in the rapidity range [Formula: see text]. The transverse momentum spectra, measured as a function of the multiplicity, have a p[Formula: see text] range from 0 to 15 GeV/c for K[Formula: see text] and from 0.3 to 21 GeV/c for [Formula: see text]. Integrated yields, mean transverse momenta and particle ratios are reported and compared with results in pp collisions at [Formula: see text][Formula: see text] 7 TeV and Pb-Pb collisions at [Formula: see text][Formula: see text] 2.76 TeV. In Pb-Pb and p-Pb collisions, K[Formula: see text] and [Formula: see text] probe the hadronic phase of the system and contribute to the study of particle formation mechanisms by comparison with other identified hadrons. For this purpose, the mean transverse momenta and the differential proton-to-[Formula: see text] ratio are discussed as a function of the multiplicity of the event. The short-lived K[Formula: see text] is measured to investigate re-scattering effects, believed to be related to the size of the system and to the lifetime of the hadronic phase.

Inclusive quarkonium production at forward rapidity in pp collisions at [Formula: see text]TeV

We report on the inclusive production cross sections of [Formula: see text], [Formula: see text], [Formula: see text](1S), [Formula: see text](2S) and [Formula: see text](3S), measured at forward rapidity with the ALICE detector in [Formula: see text] collisions at a center-of-mass energy [Formula: see text] TeV. The analysis is based on data collected at the LHC and corresponds to an integrated luminosity of 1.23 pb[Formula: see text]. Quarkonia are reconstructed in the dimuon-decay channel. The differential production cross sections are measured as a function of the transverse momentum [Formula: see text] and rapidity y, over the [Formula: see text] ranges [Formula: see text] GeV/c for [Formula: see text], [Formula: see text] GeV/c for all other resonances, and for [Formula: see text]. The cross sections, integrated over [Formula: see text] and y, and assuming unpolarized quarkonia, are [Formula: see text] [Formula: see text]b, [Formula: see text] [Formula: see text]b, [Formula: see text] nb, [Formula: see text] nb and [Formula: see text] nb, where the first uncertainty is statistical and the second one is systematic. These values agree, within at most [Formula: see text], with measurements performed by the LHCb collaboration in the same rapidity range.

Anisotropic Flow of Charged Particles in Pb-Pb Collisions at √[s{NN}]=5.02 TeV

We report the first results of elliptic (v_{2}), triangular (v_{3}), and quadrangular (v_{4}) flow of charged particles in Pb-Pb collisions at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=5.02  TeV with the ALICE detector at the CERN Large Hadron Collider. The measurements are performed in the central pseudorapidity region |η|<0.8 and for the transverse momentum range 0.2<p_{T}<5  GeV/c. The anisotropic flow is measured using two-particle correlations with a pseudorapidity gap greater than one unit and with the multiparticle cumulant method. Compared to results from Pb-Pb collisions at sqrt[s_{NN}]=2.76  TeV, the anisotropic flow coefficients v_{2}, v_{3}, and v_{4} are found to increase by (3.0±0.6)%, (4.3±1.4)%, and (10.2±3.8)%, respectively, in the centrality range 0%-50%. This increase can be attributed mostly to an increase of the average transverse momentum between the two energies. The measurements are found to be compatible with hydrodynamic model calculations. This comparison provides a unique opportunity to test the validity of the hydrodynamic picture and the power to further discriminate between various possibilities for the temperature dependence of shear viscosity to entropy density ratio of the produced matter in heavy-ion collisions at the highest energies.

Multiplicity and transverse momentum evolution of charge-dependent correlations in pp, p-Pb, and Pb-Pb collisions at the LHC

We report on two-particle charge-dependent correlations in pp, p-Pb, and Pb-Pb collisions as a function of the pseudorapidity and azimuthal angle difference, [Formula: see text] and [Formula: see text] respectively. These correlations are studied using the balance function that probes the charge creation time and the development of collectivity in the produced system. The dependence of the balance function on the event multiplicity as well as on the trigger and associated particle transverse momentum ([Formula: see text]) in pp, p-Pb, and Pb-Pb collisions at [Formula: see text] 7, 5.02, and 2.76 TeV, respectively, are presented. In the low transverse momentum region, for [Formula: see text] GeV/c, the balance function becomes narrower in both [Formula: see text] and [Formula: see text] directions in all three systems for events with higher multiplicity. The experimental findings favor models that either incorporate some collective behavior (e.g. AMPT) or different mechanisms that lead to effects that resemble collective behavior (e.g. PYTHIA8 with color reconnection). For higher values of transverse momenta the balance function becomes even narrower but exhibits no multiplicity dependence, indicating that the observed narrowing with increasing multiplicity at low [Formula: see text] is a feature of bulk particle production.

Comparison Between IGL-1 and HTK Preservation Solutions in Deceased Donor Liver Transplantation

The effectiveness of liver preservation solutions remains in evidence. Cold ischemia time, steatosis, expanded criterion donors, operational cost, and survival represent important roles in its success. In a prospective cohort study between August 2009 and April 2014, 178 patients were allocated into an Institut Georges Lopez - 1 (IGL-1) solution group (63.5%) or histidine-tryptophan-ketoglutarate (HTK) group (36.5%). There were no differences among recipient's characteristics including age, skin color, gender, Model for End-stage Liver Disease score, acute rejection, cholestasis, and reperfusion syndrome incidences. Also, donors, age average, skin color, donor risk index, time in intensive care unit, hemodynamic variables, infections, and steatosis incidences were similar. The average cold ischemia time was 494 minutes in the IGL-1 group and 489 minutes in the HTK group (P = .77). Alanine aminotransferase and aspartate aminotransferase serum levels on the first postoperative day were 707 and 1185 mg/dL, respectively, with IGL-1 and 1298 and 2291 mg/dL, respectively, with HTK (P = .016) and similar at day 15 (P > .88). The incidence of delayed graft function was 4.5% with IGL-1 and 4.6% with HTK (P = .90). The incidence primary nonfunction was 2.7% with IGL-1 and 3.1% with HTK (P = .71). The incidence of perioperative death was 11.5% with IGL-1 and 13.8% with HTK (P = .94). The survival in 30 months was 86% in IGL-1 group and 82% in HTK group (P = .66). Both preservation solutions are efficient to liver transplantations with deceased donors. Major prospective trials are necessary to evaluate each preservation solution's particularities. The preservation solution availability in each transplantation center must guide its use at the present moment.

Survey About the Cancer Risk of Renal Transplant Recipients

INTRODUCTION

There is a greater risk of malignant tumors developing in kidney transplant patients. Due to this, early detection is of outmost importance, in which screening tests play an important role.

METHODS

We have conducted a survey among renal transplant recipients to assess individual risk factors.

RESULTS

Of 530 respondents, 55 developed post-transplantation tumors. Cutaneous tumors (36%) and kidney cancer (16%) were the most frequent. In total, 59% of recipients were over the age of 50, 61.7% were over the normal body-mass index range, 40.3% smoked or used to smoke, and 21.8% had diabetes. Five patients had hepatitis B virus and 11 were hepatitis C virus-positive. Malignancies developed significantly more frequent in men than in women (P = .04). The progressing of age (P = .0001) and the time elapsed after transplantation (P < .01) also were associated with a significant increase in the occurrence of post-transplantation tumors.

CONCLUSION

We have created a database to facilitate a more personalized and efficient screening program for immunocompromised patients.

Measurement of pion, kaon and proton production in proton-proton collisions at [Formula: see text] TeV

The measurement of primary [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] production at mid-rapidity ([Formula: see text] 0.5) in proton-proton collisions at [Formula: see text][Formula: see text] 7 TeV performed with a large ion collider experiment at the large hadron collider (LHC) is reported. Particle identification is performed using the specific ionisation energy-loss and time-of-flight information, the ring-imaging Cherenkov technique and the kink-topology identification of weak decays of charged kaons. Transverse momentum spectra are measured from 0.1 up to 3 GeV/[Formula: see text] for pions, from 0.2 up to 6 GeV/[Formula: see text] for kaons and from 0.3 up to 6 GeV/[Formula: see text] for protons. The measured spectra and particle ratios are compared with quantum chromodynamics-inspired models, tuned to reproduce also the earlier measurements performed at the LHC. Furthermore, the integrated particle yields and ratios as well as the average transverse momenta are compared with results at lower collision energies.

Production of [Formula: see text] and [Formula: see text] in proton-proton collisions at [Formula: see text] 7 TeV

The production of the strange and double-strange baryon resonances ([Formula: see text], [Formula: see text]) has been measured at mid-rapidity ([Formula: see text][Formula: see text]) in proton-proton collisions at [Formula: see text] [Formula: see text] 7 TeV with the ALICE detector at the LHC. Transverse momentum spectra for inelastic collisions are compared to QCD-inspired models, which in general underpredict the data. A search for the [Formula: see text] pentaquark, decaying in the [Formula: see text] channel, has been carried out but no evidence is seen.

Exclusive J/ψ photoproduction off protons in ultraperipheral p-Pb collisions at √(s(NN))=5.02 TeV

We present the first measurement at the LHC of exclusive J/ψ photoproduction off protons, in ultraperipheral proton-lead collisions at sqrt[s_{NN}]=5.02  TeV. Events are selected with a dimuon pair produced either in the rapidity interval, in the laboratory frame, 2.5<y<4 (p-Pb) or -3.6<y<-2.6 (Pb-p), and no other particles observed in the ALICE acceptance. The measured cross sections σ(γ+p→J/ψ+p) are 33.2±2.2(stat)±3.2(syst)±0.7(theor)  nb in p-Pb and 284±36(stat)_{-32}^{+27}(syst)±26(theor)  nb in Pb-p collisions. We measure this process up to about 700 GeV in the γp center of mass, which is a factor of two larger than the highest energy studied at HERA. The data are consistent with a power law dependence of the J/ψ photoproduction cross section in γp energies from about 20 to 700 GeV, or equivalently, from Bjorken x scaling variable between ∼2×10^{-2} and ∼2×10^{-5}, thus indicating no significant change in the gluon density behavior of the proton between HERA and LHC energies.

Measurement of prompt D-meson production in p-Pb collisions at √(s(NN))=5.02 TeV

The p_{T}-differential production cross sections of the prompt charmed mesons D^{0}, D^{+}, D^{*+}, and D_{s}^{+} and their charge conjugate in the rapidity interval -0.96<y_{cms}<0.04 were measured in p-Pb collisions at a center-of-mass energy sqrt[s_{NN}]=5.02  TeV with the ALICE detector at the LHC. The nuclear modification factor R_{pPb}, quantifying the D-meson yield in p-Pb collisions relative to the yield in pp collisions scaled by the number of binary nucleon-nucleon collisions, is compatible within the 15%-20% uncertainties with unity in the transverse momentum interval 1<p_{T}<24  GeV/c. No significant difference among the R_{pPb} of the four D-meson species is observed. The results are described within uncertainties by theoretical calculations that include initial-state effects. The measurement adds experimental evidence that the modification of the momentum spectrum of D mesons observed in Pb-Pb collisions with respect to pp collisions is due to strong final-state effects induced by hot partonic matter.

Measurement of quarkonium production at forward rapidity in [Formula: see text] collisions at [Formula: see text]TeV

The inclusive production cross sections at forward rapidity of [Formula: see text], [Formula: see text], [Formula: see text](1S) and [Formula: see text](2S) are measured in [Formula: see text] collisions at [Formula: see text] with the ALICE detector at the LHC. The analysis is based on a data sample corresponding to an integrated luminosity of 1.35 pb[Formula: see text]. Quarkonia are reconstructed in the dimuon-decay channel and the signal yields are evaluated by fitting the [Formula: see text] invariant mass distributions. The differential production cross sections are measured as a function of the transverse momentum [Formula: see text] and rapidity [Formula: see text], over the ranges [Formula: see text] GeV/c for [Formula: see text], [Formula: see text] GeV/c for all other resonances and for [Formula: see text]. The measured cross sections integrated over [Formula: see text] and [Formula: see text], and assuming unpolarized quarkonia, are: [Formula: see text] [Formula: see text]b, [Formula: see text] [Formula: see text]b, [Formula: see text] nb and [Formula: see text] nb, where the first uncertainty is statistical and the second one is systematic. The results are compared to measurements performed by other LHC experiments and to theoretical models.

Energy dependence of the transverse momentum distributions of charged particles in pp collisions measured by ALICE

Differential cross sections of charged particles in inelastic pp collisions as a function of p_T have been measured at [Formula: see text] at the LHC. The p_T spectra are compared to NLO-pQCD calculations. Though the differential cross section for an individual [Formula: see text] cannot be described by NLO-pQCD, the relative increase of cross section with [Formula: see text] is in agreement with NLO-pQCD. Based on these measurements and observations, procedures are discussed to construct pp reference spectra at [Formula: see text] up to p_T=50 GeV/c as required for the calculation of the nuclear modification factor in nucleus-nucleus and proton-nucleus collisions.

Directed flow of charged particles at midrapidity relative to the spectator plane in Pb-Pb collisions at √(s(NN))=2.76 TeV

The directed flow of charged particles at midrapidity is measured in Pb-Pb collisions at √(s(NN))=2.76 TeV relative to the collision symmetry plane defined by the spectator nucleons. A negative slope of the rapidity-odd directed flow component with approximately 3 times smaller magnitude than found at the highest RHIC energy is observed. This suggests a smaller longitudinal tilt of the initial system and disfavors the strong fireball rotation predicted for the LHC energies. The rapidity-even directed flow component is measured for the first time with spectators and found to be independent of pseudorapidity with a sign change at transverse momenta p(T) between 1.2 and 1.7  GeV/c. Combined with the observation of a vanishing rapidity-even p(T) shift along the spectator deflection this is strong evidence for dipolelike initial density fluctuations in the overlap zone of the nuclei. Similar trends in the rapidity-even directed flow and the estimate from two-particle correlations at midrapidity, which is larger by about a factor of 40, indicate a weak correlation between fluctuating participant and spectator symmetry planes. These observations open new possibilities for investigation of the initial conditions in heavy-ion collisions with spectator nucleons.