Measurement of the nuclear modification factor for muons from charm and bottom hadrons in Pb+Pb collisions at 5.02 TeV with the ATLAS detector

Heavy-flavour hadron production provides information about the transport properties and microscopic structure of the quark-gluon plasma created in ultra-relativistic heavy-ion collisions. A measurement of the muons from semileptonic decays of charm and bottom hadrons produced in Pb+Pb and pp collisions at a nucleon-nucleon centre-of-mass energy of 5.02 TeV with the ATLAS detector at the Large Hadron Collider is presented. The Pb+Pb data were collected in 2015 and 2018 with sampled integrated luminosities of 208 mu b(-1) and 38 mu b(-1), respectively, and pp data with a sampled integrated luminosity of 1.17 pb(-1) were collected in 2017. Muons from heavy-flavour semileptonic decays are separated from the light-flavour hadronic background using the momentum imbalance between the inner detector and muon spectrometer measurements, and muons originating from charm and bottom decays are further separated via the muon track's transverse impact parameter. Differential yields in Pb+Pb collisions and differential cross sections in pp collisions for such muons are measured as a function of muon transverse momentum from 4 GeV to 30 GeV in the absolute pseudorapidity interval vertical bar eta vertical bar < 2. Nuclear modification factors for charm and bottom muons are presented as a function of muon transverse momentum in intervals of Pb+Pb collision centrality. The bottom muon results are the most precise measurement of b quark nuclear modification at low transverse momentum where reconstruction of B hadrons is challenging. The measured nuclear modification factors quantify a significant suppression of the yields of muons from decays of charm and bottom hadrons, with stronger effects for muons from charm hadron decays

A search for an unexpected asymmetry in the production of e+μ− and e−μ+ pairs in proton-proton collisions recorded by the ATLAS detector at root s = 13 TeV

This search, a type not previously performed at ATLAS, uses a comparison of the production cross sections for e(+)mu(-) and e(-)mu(+) pairs to constrain physics processes beyond the Standard Model. It uses 139 fb(-1) of proton-proton collision data recorded at root s = 13 TeV at the LHC. Targeting sources of new physics which prefer final states containing e(+)mu(-) and e(-)mu(+), the search contains two broad signal regions which are used to provide model-independent constraints on the ratio of cross sections at the 2% level. The search also has two special selections targeting supersymmetric models and leptoquark signatures. Observations using one of these selections are able to exclude, at 95% confidence level, singly produced smuons with masses up to 640 GeV in a model in which the only other light sparticle is a neutralino when the R-parity-violating coupling lambda(23)(1)' is close to unity. Observations using the other selection exclude scalar leptoquarks with masses below 1880 GeV when g(1R)(eu) = g(1R)(mu c) = 1, at 95% confidence level. The limit on the coupling reduces to g(1R)(eu) = g(1R)(mu c) = 0.46 for a mass of 1420 GeV

Differential cross-section measurements of the production of four charged leptons in association with two jets using the ATLAS detector

Differential cross-sections are measured for the production of four charged leptons in association with two jets. These measurements are sensitive to final states in which the jets are produced via the strong interaction as well as to the purely-electroweak vector boson scattering process. The analysis is performed using proton-proton collision data collected by ATLAS at √s = 13 TeV and with an integrated luminosity of 140 fb−1. The data are corrected for the effects of detector inefficiency and resolution and are compared to state-of-the-art Monte Carlo event generator predictions. The differential cross-sections are used to search for anomalous weak-boson self-interactions that are induced by dimension-six and dimension-eight operators in Standard Model effective field theory

Structural damage caused by the Skopje Earthquake of 1963 : a report to the Committee on Masonry and Reinforced Concrete of the American Society of Civil Engineers and the American Concrete Institute /

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Evaluation Of Mlc Leaf Positioning Accuracy For Static And Dynamic Imrt Treatments Using David In Vivo Dosimetric System*

Accuracy and precision of leaf positioning in multileaf collimators (MLCs) are significant factors for the accuracy of IMRT treatments. This study aimed to investigate the accuracy and repeatability of the MLC leaf positioning via the DAVID in vivo dosimetric system for dynamic and static MLC systems. The DAVID system was designed as multiwire transmission ionization chamber which is placed in accessory holder of linear accelerators. Each wire of DAVID system corresponds to a MLC leaf‐pair to verify the leaf positioning accuracy during IMRT treatment and QA. In this study, verifications of IMRT plans of five head and neck (H&N) and five prostate patients treated in a Varian DHX linear accelerator with 80‐leaf MLC were performed using DAVID system. Before DAVID‐based dosimetry, Electronics Portal Imaging Device (EPID) and PTW 2D ARRAY dosimetry system were used for 2D verification of each plan. The measurements taken by DAVID system in the first day of the treatments were used as reference for the following measurements taken over the next four weeks. The deviations in leaf positioning were evaluated by “Total Deviation (TD)” parameter calculated by DAVID software. The delivered IMRT plans were originally prepared using dynamic MLC method. The same plans were subsequently calculated based on static MLC method with three different intensity levels of five (IL5), 10 (IL10) and 20 (IL20) in order to compare the performances of MLC leaf positioning repeatability for dynamic and static IMRT plans. The leaf positioning accuracy is also evaluated by analyzing DynaLog files based on error histograms and root mean square (RMS) errors of leaf pairs’ positions. Moreover, a correlation analysis between simultaneously taken DAVID and EPID measurements and DynaLog file recordings was subsequently performed. In the analysis of DAVID outputs, the overall deviations of dynamic MLC‐based IMRT calculated from the deviations of the four weeks were found as 0.55%±0.57% and 1.48%±0.57% for prostate and H&N patients, respectively. The prostate IMRT plans based on static MLC method had the overall deviations of 1.23%±0.69%, 3.07%±1.07%, and 3.13%±1.29% for intensity levels of IL5, IL10, and IL20, respectively. Moreover, the overall deviations for H&N patients were found as 1.87%±0.86%, 3.11%±1.24%, and 2.78%±1.31% for the static MLC‐based IMRT plans with intensity levels of IL5, IL10 and IL20, respectively. Similar with the DAVID results, the error rates in DynaLog files showed upward movement comparing the dynamic IMRT with static IMRT with high intensity levels. In respect to positioning errors higher than 0.005 cm, static prostate IMRT plans with intensity levels of IL10 and IL20 had 1.5 and 2.6 times higher error ratios than dynamic prostate IMRT plans, respectively, while these values stepped up to 8.4 and 12.0 for H&N cases. On the other hand, according to the leaf pair readings, reconstructed dose values from DynaLog files had significant correlation (r=0.80) with DAVID and EPID readings while a stronger relationship (r=0.98) was found between the two dosimetric systems. The correlation coefficients for deviations from reference plan readings were found in the interval of −0.21–0.16 for all three systems. The dynamic MLC method showed higher performance in repeatability of leaf positioning than static MLC methods with higher intensity levels even though the deviations in the MLC leaf positioning were found to be under the acceptance threshold for all MLC methods. The high intensity levels increased the positioning deviations along with the delivery complexity of the static MLC‐based IMRT plans. Moreover, DAVID and EPID readings and DynaLog recordings showed mutually strong correlation, while no significant relationship was found between deviations from reference values., PACS number(s): 87.56.J‐PubMedWoSScopu

Clinical Features and Etiology of Adult Patients with Fever and Rash

BACKGROUND: Patients with fever and rash often pose an urgent diagnostic and therapeutic dilemma for the clinician. The nonspecificity of many fever and rash syndromes mandates a systemic approach to diagnosis. OBJECTIVE: We aimed to determine the etiology of fever and rash in 100 adult patients followed-up as in- or outpatients prospectively. METHODS: All the patients, who presented with rash and fever, were followed-up prospectively and their clinical and laboratory studies were evaluated. RESULTS: The median age was 35 years (14~79 years); 45 were female and 55 were male. Patients were divided into 3 groups according to the etiology: infectious (50%), noninfectious (40%) and undiagnosed (10%). The most common type of rash was maculopapular, and the most common 5 causes were measles, cutaneous drug reactions, varicella, adult-onset Still's disease (ASD) and rickettsial disease. Viral diseases among infectious causes and cutaneous drug reactions, among the noninfectious causes, were determined as the main diseases. The mortality rate was 5% and the reasons of mortality were as follows: toxic epidermal necrolysis (2 patients), ASD (1), staphylococcal toxic shock syndrome (1) and graft-versus-host disease (1). CONCLUSION: Adult patients with fever and rash had a wide differential diagnosis. The most common type of rash was determined as maculopapular, and the most frequent five diseases were measles, drug reactions, chickenpox, ASD and rickettsial infection. Viral diseases among infectious causes and drug reactions among noninfectious causes were determined as the leading etiologies

Padova Charter on personal injury and damage under civil-tort law: Medico-legal guidelines on methods of ascertainment and criteria of evaluation

Compensation for personal damage, defined as any pecuniary or non-pecuniary loss causally related to a personal injury under civil-tort law, is strictly based on the local jurisdiction and therefore varies significantly across the world. This manuscript presents the first ''International Guidelines on Medico-Legal Methods of Ascertainment and Criteria of Evaluation of Personal Injury and Damage under Civil-Tort Law''. This consensus document, which includes a step-by-step illustrated explanation of flow charts articulated in eight sequential steps and a comprehensive description of the ascertainment methodology and the criteria of evaluation, has been developed by an International Working Group composed of juridical and medico-legal experts and adopted as Guidelines by the International Academy of Legal Medicine (IALM)