The RD52 calorimeter uses the dual-readout principle to detect both electromagnetic and hadronic showers, as well as muons. Scintillation and Cherenkov light provide the two signals which, in ...combination, allow for superior hadronic performance. In this paper, we report on detailed, GEANT4 based Monte Carlo simulations of the performance of this instrument. The results of these simulations are compared in great detail to measurements that have been carried out and published by the DREAM Collaboration. This comparison makes it possible to understand subtle details of the shower development in this unusual particle detector. It also allows for predictions of the improvement in the performance that may be expected for larger detectors of this type. These studies also revealed some inadequacies in the GEANT4 simulation packages, especially for hadronic showers, but also for the Cherenkov signals from electromagnetic showers.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
A comparison of BGO and BSO crystals used in the dual-readout mode Akchurin, N.; Bedeschi, F.; Cardini, A. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
06/2011, Volume:
640, Issue:
1
Journal Article
Peer reviewed
We report on a systematic study of the properties of two high-
Z scintillating crystals, bismuth germanate (BGO) and bismuth silicate (BSO), in view of the possible application of such crystals in ...dual-readout calorimeters. Whereas the light attenuation characteristics of both crystals are about the same, BSO offers a considerably higher Cherenkov light yield, and with a given UV filter the separation between the Cherenkov and scintillation signals is substantially better in this crystal.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Remdesivir is a broad‐spectrum antiviral agent able to inhibit the RNA polymerase of SARS‐CoV‐2. At present, studies focusing on the effect of remdesivir on viral load (VL) are few and with ...contrasting results. Aim of the present study was to evaluate the effect of remdesivir on SARS‐CoV‐2 VL from nasopharyngeal swabs (cycle threshold criterion) in a sample of patients treated with the drug, compared with patients who did not receive the antiviral treatment. This retrospective analysis evaluated patients with (1) real‐time polymerase chain reaction (RT‐PCR) confirmed COVID‐19 diagnosis and (2) availability of at least two positive nasopharyngeal swabs analysed with the same analytic platform (ORF target gene, Ingenius ELITe, ELITechGroup, Puteaux, France). Upper respiratory specimens from nasopharyngeal swabs were collected at admission (T0) and 7–14 days after treatment, upon clinical decision. A total of 27 patients treated with remdesivir (Group A) met the inclusion criteria and were compared with 18 patients (Group B) treated with standard care, matched for baseline clinical characteristics. At baseline, both remdesivir‐treated and nontreated patients showed comparable VLs (21.73 ± 6.81 vs. 19.27 ± 5.24, p = 0.348). At the second swab, remdesivir‐treated patients showed a steeper VL reduction with respect to controls (34.28 ± 7.73 vs. 27.22 ± 3.92; p < 0.001). Longitudinal linear model estimated a mean decrease in cycle threshold equal to 0.61 (SE: 0.09) per day in remdesivir‐treated versus 0.33 (SE: 0.10) per day in remdesivir nontreated patients (p for heterogeneity = 0.045). The present study shows that the administration of remdesivir in hospitalized COVID‐19 patients significantly reduces the VL on nasopharyngeal swabs.
Highlights
Remdesivir's effect on viral load has not been extensively studied
Remdesivir‐treated patients showed a steeper viral load reduction compared to controls
This could impact on the optimal timing of administration to prevent disease progression
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Abstract One of the main problems in transplant surgery is the preservation of the organ during the cold ischemic time. The interrupted blood supply triggers a cascade of biological modifications ...resulting in cell death, which predisposes to discharge of a large quantity of toxic metabolites at the moment of organ reperfusion. Many approaches have been studied to prevent the toxic processes. Immediately after procurement, kidneys are flushed with these solutions. Two main: techniques of organ preservation are cold static storage and hypothermic machine perfusion (HMP). Based on age and comorbidities, individuals can be generally divided into 2 groups: ideal and marginal donors. Characteristics of organs from marginal donors are associated with an increased rate of delayed graft function and primary graft nonfunction (PNF), which reduce transplant survival and increase the acute rejection risk. In the last 20 years, the United Network of Organ Sharing has reported a 170% increase in deceased donors older than 50 years of age. Techniques of perfusion have been demonstrated to play a pivotal role in graft function after transplantation. Some studies suggest that HMP may improve outcomes after transplantation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The increased survival after a severe acquired brain injury (sABI) raise the problem of making most effective the treatments in Intensive Care Unit (ICU)/Neurointensive Care Unit (NICU), also ...integrating rehabilitation care. Despite previous studies reported that early mobilization in ICU was effective in preventing complications and reducing hospital stay, few studies addressed the rehabilitative management of sABI patients in ICU/NICU.
To collect clinical and functional data about the early rehabilitative management of sABI patients during ICU/NICU stay.
Prospective, observational, multicenter study.
Fourteen facilities supplied by intensive neurorehabilitation units and ICU/NICUs.
Consecutive sABI patients admitted to ICU/NICU.
Patients were evaluated at admission and then every 3-5 days. Clinical, functional and rehabilitative data, including Glasgow Coma Scale (GCS), Disability Rating Scale (DRS), The Rancho Los Amigos Levels of Cognitive Functioning Scale (LCF), Early Rehabilitation Barthel Index (ERBI), Glasgow Outcome scale (GOS) and Functional Independence Measure (FIM) were collected.
One hundred and two patients (F/M 44/58) were enrolled. The mean duration of ICU stay was 24.7±13.9 days and the first rehabilitative evaluation occurred after 8.7±8.8 days. Regular postural changes and multijoint mobilization were prescribed in 63.7% and 64.7% cases, respectively. The mean session duration was 38±11.5 minutes. Swallowing evaluation was performed in 14.7% patients, psychological support was provided to 12.7% of patients' caregivers, while 17.6% received a psycho-educational intervention, and 28.4% were involved in interdisciplinary team meetings. The main discharge destinations were Severe Acquired Brain Injury rehabilitation units for 43.7%, intensive neurorehabilitation units for 20.7%.
Data showed that early rehabilitation was not diffusely performed in sABI subjects in ICU/NICU and rehabilitative interventions were variable; one-third of subjects were not referred to dedicated rehabilitation unit at discharge.
The study stresses the need to spread and implement a rehabilitative culture also for critical ill patients due to neurological diseases.
New particles with large masses that decay into hadronically interacting particles are predicted by many models of physics beyond the Standard Model. A search for a massive resonance that decays into ...pairs of dijet resonances is performed using 140 fb −1 of proton-proton collisions at √ s =13 TeV recorded by the ATLAS detector during Run 2 of the Large Hadron Collider. Resonances are searched for in the invariant mass of the tetrajet system, and in the average invariant mass of the pair of dijet systems. A data-driven background estimate is obtained by fitting the tetrajet and dijet invariant mass distributions with a four-parameter dijet function and a search for local excesses from resonant production of dijet pairs is performed. No significant excess of events beyond the Standard Model expectation is observed, and upper limits are set on the production cross sections of new physics scenarios.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
The inclusive Higgs boson production cross-section is measured in the di-photon and the $ZZ^* \to 4 \ell$ decay channels using 31.4 and 29.0 fb$^{-1}$ of $pp$ collision data respectively, collected ...with the ATLAS detector at a centre-of-mass energy of $\sqrt{s}=13.6$ TeV. To reduce the model dependence, the measurement in each channel is restricted to a particle-level phase space that closely matches the channel's detector-level kinematic selection, and it is corrected for detector effects. These measured fiducial cross-sections are $\sigma_{\mathrm{fid},\gamma \gamma} = 76^{+14}_{-13}$ fb, and $\sigma_{\mathrm{fid},4 \ell} = 2.80 \pm 0.74$ fb, in agreement with the corresponding Standard Model predictions of $67.6 \pm 3.7 $ fb and $3.67 \pm 0.19 $ fb. Assuming Standard Model acceptances and branching fractions for the two channels, the fiducial measurements are extrapolated to the full phase space yielding total cross-sections of $\sigma(pp \to H) = 67^{+12}_{-11}$ pb and $46 \pm 12$ pb at $13.6$ TeV from the di-photon and $ZZ^* \to 4 \ell$ measurements respectively. The two measurements are combined into a total cross-section measurement of $\sigma(pp \to H)= 58.2 \pm 8.7$ pb, to be compared with the Standard Model prediction of $\sigma(pp \to H)_\mathrm{SM} = 59.9 \pm 2.6 $ pb.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•Use of an experimental facility, STARDUST, to analyze the dust resuspension problem inside the tokamak in case of loss of vacuum accident.•PIV technique implementation to track the dust during a ...LOVA reproduction inside STARDUST.•Data imaging techniques to analyze dust velocity field: first results and data discussion.
An important issue related to future nuclear fusion reactors fueled with deuterium and tritium is the creation of large amounts of dust due to several mechanisms (disruptions, ELMs and VDEs). The dust size expected in nuclear fusion experiments (such as ITER) is in the order of microns (between 0.1 and 1000μm). Almost the total amount of this dust remains in the vacuum vessel (VV). This radiological dust can re-suspend in case of LOVA (loss of vacuum accident) and these phenomena can cause explosions and serious damages to the health of the operators and to the integrity of the device. The authors have developed a facility, STARDUST, in order to reproduce the thermo fluid-dynamic conditions comparable to those expected inside the VV of the next generation of experiments such as ITER in case of LOVA. The dust used inside the STARDUST facility presents particle sizes and physical characteristics comparable with those that created inside the VV of nuclear fusion experiments. In this facility an experimental campaign has been conducted with the purpose of tracking the dust re-suspended at low pressurization rates (comparable to those expected in case of LOVA in ITER and suggested by the General Safety and Security Report ITER-GSSR) using a fast camera with a frame rate from 1000 to 10,000 images per second. The velocity fields of the mobilized dust are derived from the imaging of a two-dimensional slice of the flow illuminated by optically adapted laser beam. The aim of this work is to demonstrate the possibility of dust tracking by means of image processing with the objective of determining the velocity field values of dust re-suspended during a LOVA.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The fragmentation of high-energy gluons at small opening angles is largely unconstrained by present measurements. Gluon splitting to b-quark pairs is a unique probe into the properties of gluon ...fragmentation because identified b-tagged jets provide a proxy for the quark daughters of the initial gluon. In this study, key differential distributions related to the g→b¯b process are measured using 33 fb−1 of √s=13 TeV pp collision data recorded by the ATLAS experiment at the LHC in 2016. Jets constructed from charged-particle tracks, clustered with the anti-kt jet algorithm with radius parameter R=0.2, are used to probe angular scales below the R=0.4 jet radius. The observables are unfolded to particle level in order to facilitate direct comparisons with predictions from present and future simulations. Multiple significant differences are observed between the data and parton shower Monte Carlo predictions, providing input to improve these predictions of the main source of background events in analyses involving boosted Higgs bosons decaying into b-quarks.
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