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Measurement of the associated production of the Higgs boson with a vector boson in 13 TeV pp collisions with the ATLAS detector
No full textAfter the Higgs discovery at LHC in 2012, most of ATLAS analyses are focusing the attention on precision measurements of Higgs kinematic properties and on the search of new decay modes sensitive to physics Beyond the Standard Model. One of the most interesting channels is the Higgs boson decay into two b-quarks due to the large branching ratio (58%). The best sensitivity is presently
obtained by studying the associated Higgs boson production with a vector boson V (V = W or Z) decaying leptonically. The same dataset has been re-interpreted in the Simplified Template Cross Section framework. This framework facilitates the measurement of the differential pp → V H cross section used to extract information on the Higgs couplings and to put limits on Beyond the Standard Model effects. In this paper an overview of the most recent results on the observation of V H production and H → b¯b decay mode will be presented, together with the measurements of the V H, H → b¯b production as a function of the vector boson transverse momentum
First-principles approach to novel 2D magnets
No full textThere is currently an increasing enthusiasm towards long-range magnetic order in two-dimensional materials (such as CrI3 and Cr2Ge2Te6), from the fundamental and from the applicative point of view, from theory and from experiments. In this work, we carry out an extensive investigation based on density functional theory on an extended class of such materials, starting from the database of exfoliable materials reported by N. Mounet etal.. In the aim of optimizing the properties of 2D-ferromagnets and increasing the Curie temperature, our analysis focuses on tri- and di- halides (with formula M−(VII)3 and M−(VII)2, where M is a transition metal and VII = Cl, Br, I). In addition to structural and electronic properties, we analyse the magnetic properties, in terms of magnetic moments, Heisenberg exchange coupling constants and magnetic anisotropy energy. Some of the considered materials show exchange coupling constants significantly larger than the prototypical CrI3, so they might be promising candidates for larger transition temperatures
Coating thickness of plated objects using XRF technique concentrations
No full textThe coating layer thickness of the double-layer objects was estimated using the concentration value of an element of the covering layer or of the substrate after obtaining suitable calibration curves using reference materials. The
x-ray fluorescence technique was used with a handheld instrument to determine the concentration of elements. Various experimental configurations were built using gold- and silver-plated materials. The concentration calibrations curve as a function of coating layer thickness were successfully applied to gold-plated brass and copper jewelry, gold-plated samples and an ancient silver coin. The results obtained using the concentrations are in good agreement with those of other more elaborate
methods
Migrazioni di virus. Numeri e linguaggi
Get PDFLa pandemia di covid-19 segna per certi versi una cesura con il mondo globalizzato degli ultimi decenni, non solo per il suo imprevisto e tragico decorso ma anche per i cambiamenti profondi che porta nelle vite personali e interpersonali, oltre che sul piano sociale ed economico.
Secondo differenti prospettive disciplinari, il volume intende contribuire alla comprensione di un periodo critico e mutevole, con studi incentrati sugli aspetti quantitativi del fenomeno pandemico e altri relativi all’analisi dei contesti storici, culturali e artistici che lo interpretano, lo elaborano e lo rappresentano.
The covid-19 pandemic marks in some ways a pause in the globalization process of the world of the last decades, not only for its unexpected and tragic course but also for the profound effects on the personal and interpersonal lives, and on the social and economic sphere.
According to different disciplinary perspectives, this volume intends to contribute to the understanding of a critical and changing period, with some studies focusing on the quantitative aspects of the pandemic phenomenon and others relating to the analysis of historical, cultural and artistic contexts that interpret, elaborate and represent it
VIH-SIDA et droits humains à la Maison d’Arrêt et de Correction (MACA) d’Abidjan
Get PDFLe droit aux soins et celui de la dignité font partie intégrante des principes fondamentaux réaffirmés par la constitution ivoirienne. La mise en application de cette dualité, interpelle le vécu des détenus infectés par le VIH/SIDA. Cette étude poursuit deux objectifs : expliquer la prévalence du VIH/SIDA au sein des détenus de la maison d’Arrêt et de Correction d’Abidjan (MACA) – Côte d’Ivoire et dénoncer les atteintes aux droits des détenus vivant avec le VIH/SIDA.
Au plan méthodologique, nous avons recouru à la recherche documentaire, l’observation participante et l’entretien semi-direct pour recueillir les informations. L’étude a été réalisée au sein de la population carcérale de la MACA auprès de trente-cinq (35) enquêtés. L’analyse qualitative a été utilisée afin de comprendre le sens des discours des enquêtés. Les résultats indiquent que les conditions d’enfermement des détenus, l’absence de programme permanent de sensibilisation et de prise en charge et les comportements à risque constituent des facteurs aggravants du VIH en prison. Ils montrent également que les insuffisances de la prise en charge des détenus vivant avec le VIH pourraient laisser entrevoir une méconnaissance de leurs droits
Diaphragmatic Rupture and Gastric Perforation in a Patient with COVID-19 Pneumonia
Get PDFWe describe the case of a young female patient admitted to our emergency department during the Italian COVID-19 epidemic, for fever and dry cough associated with symptoms of gastric reflux over the previous 5 days. Lung ultrasound showed diffuse bilateral B lines with irregular pleural thickening, and consolidation with air bronchogram and slight pleural effusion in the lower left lobe. Chest HRCT and abdominal CT scanning with contrast revealed diaphragmatic rupture with gastric perforation, and atelectasis of the left pulmonary lobe with unilateral pleural effusion, diffuse ground-glass opacities and multiple small consolidations in both lobes. A nasopharyngeal swab for 2019-nCoV was positive. A diagnosis of diaphragmatic rupture and gastric perforation in COVID-19 pneumonia was made. The patient was immediately hospitalized and surgically treated. Treatment for COVID-19 and empiric antibiotic therapy were promptly starte
Bilateral Decompressive Craniectomy in Malignant Cerebral Venous Thrombosis
Get PDFIntroduction: Despite the extremely favourable prognosis of patients with cerebral venous thrombosis (CVT), death occurs in 10–15% of patients. In severe cases of malignant CVT with supratentorial haemorrhagic lesions, cerebral oedema and brain herniation, decompressive surgery may be the only life-saving treatment.Patient and methods: We present the case of a puerperal young woman with progressive headache, seizures and decreased alertness. Thrombosis of the entire superior sagittal sinus with bifrontal venous infarcts and midline shift was confirmed by magnetic resonance imaging with venography sequencing. Despite medical treatment with anticoagulation, progressive neurological deterioration was observed, so bilateral, frontal decompressive craniectomy was performed. Results: At the 6-month follow-up, we observed partial functional recovery with a modified Rankin score of 3.Discussion: Bilateral decompressive craniectomy may be a life-saving therapeutic option when medical therapy fails and there are clinical and radiological features of progression in both cerebral hemispheres
Pneumocephalus Associated with Aggressive Pneumococcal Meningitis
Get PDFA 44-year-old woman presented with headache and delirium. Brain tomography indicated pneumocephalus, while blood and cerebrospinal fluid cultures revealed Streptococcus pneumoniae. Despite antibiotic treatment and admission to the intensive care unit, the patient died 3 days later. Pneumocephalus in association with meningitis is very rare and may be caused by gas produced by microorganisms
Elevated Adenosine Deaminase in Pleural Effusion A Case of Non-Hodgkin Lymphoma Misdiagnosis
Get PDFDespite a recent decline, tuberculosis (TB) infection is still a frequent diagnosis in Portugal. Adenosine deaminase (ADA) measurement has become an important tool in the timely diagnosis of this infection. However, ADA elevation in bodily fluids is not pathognomonic of TB infection. We present the case of a 70-year-old woman, undergoing treatment for pleural TB, diagnosed based on elevated ADA levels in a pleural effusion. Due to worsening symptoms she was readmitted, and the previous diagnosis was reconsidered. Thoracocentesis was repeated and cytometry analysis of the fluid was performed, showing the presence of diffuse large B cell lymphoma (DLBCL). DLBCL is the most frequently occurring non-Hodgkin lymphoma (NHL). Pleural involvement is rare in the initial stages. ADA elevation >250 U/l should raise suspicion of malignancy, especially in association with markedly elevated LDH levels. The purpose of this case report is to highlight that in the absence of microbiologic or histologic confirmation, a presumptive TB diagnosis should not be lightly made, and alternative diagnoses should be systematically ruled out
COVID-19 in a Patient with Accidental Drug-Induced Neutropenia
Get PDFBackground: Coronavirus disease 2019 (COVID-19) presents with a wide range of illness severity, from asymptomatic disease to severe acute respiratory distress syndrome (ARDS). Immunosuppression is considered a risk factor for severe COVID-19, but there are only few reports on disease progression in immunocompromised patients. Case Summary: We report the case of a 50-year-old patient with acute COVID-19 pneumonia, who had iatrogenic, clinically relevant bone marrow suppression due to accidental overdose with hydroxyurea, and decreased lung capacity due to a left-sided pneumonectomy 6 months earlier. Symptomatic treatment with oxygen supplementation and pulmonary physical therapy was initiated, and hydroxyurea was discontinued. Over 14 days, the patient’s blood counts slowly recovered, and his clinical condition gradually improved, such that supplemental oxygen was no longer necessary and he could be discharged. Discussion: A gradual increase in neutrophil and lymphocyte counts may be preferable to dampen a potentially detrimental immunological response triggered by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Whether patients with severe COVID-19 benefit from immunosuppressive therapy should be further evaluated