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Structure of discontinuities in beta functions in higher-derivative gauge theories
No full textWe discuss the structure of perturbative one-loop beta functions in higher-derivative gauge theories, which are quadratic in the field strengths. The action of these theories contains arbitrary integer powers n of the gauge-covariant analogue of the d’Alembert operator. We pay special attention to the discontinuities found for UV-divergences in the cases of n = 0 and n = 1. They are explained by mathematical properties of the derivation of perturbative vertices and the various usage of finite sum symbols. We also give examples of the derivation of a 3-vertex
Retiform Purpura of the Lower Limbs Associated with Levamisole-Adulterated Cocaine
Get PDFA young man was treated in hospital for sepsis, disseminated intravascular coagulation and multi-organ failure. He was a regular intranasal cocaine user up to 1 day prior to symptom onset. Clinical examination revealed extensive retiform purpura affecting both his lower limbs. Skin biopsy revealed widespread thrombosis in the small- and medium-sized vessels of the mid dermis and the subcutaneous fat with surrounding leucocytoclasis. There was also extensive ischaemic necrosis of the upper reticular and papillary dermis and focal ischaemic necrosis of the epidermis. These findings were in keeping with a thrombotic vasculopathy with associated cutaneous ischaemic necrosis, likely associated with levamisole-adulterated cocaine (LAC). An autoimmune screen showed extremely raised levels of anti-B2-glycoprotein IgM, IgG and anti-cardiolipin IgG antibodies, usually seen in antiphospholipid syndrome (APS). The literature describes how APS could be secondary to various underlying conditions, including LAC, and that levamisole toxicity may mimic APS and hence be missed
Rhabdomyolysis after Intravenous Ferric Gluconate: A Case Report
Get PDFPatients with severe iron deficiency, malabsorption or intolerance to oral iron are frequently treated with intravenous iron replacement. We report the case of a 42-year-old woman with non-erosive oligoarticular arthritis with antiparietal cell antibodies and iron deficiency anemia secondary to menorrhagia and unresponsive to oral iron preparations. She was treated with an intravenous infusion of ferric gluconate. After the first infusion of 125 mg (in 250 mL saline), she developed transient pain in her knee and wrist joints. When the dose was subsequently halved, the patient showed no adverse symptoms in the next four infusions and had normalized hemoglobin levels and iron indices. However, after a subsequent 125 mg ferric gluconate infusion she developed severe leg pain, muscular and joint stiffness, and functional impairment of her hands, right foot, and ankle. Laboratory tests showed a progressive increase in creatine kinase, transaminase, and C-reactive protein that normalized several days after the infusion. Although rhabdomyolysis is not reported among endovenous iron-induced adverse events, our findings suggest that intravenous iron infusions might have increased free iron generation promoting oxidative joint and muscular injury, which would explain the joint pain and stiffness, and rhabdomyolysis. Greater attention should be paid to the more frequent cases of myalgia occurring after iron infusion, which may underlie a rhabdomyolytic event requiring clinical observation
A Rare Presentation of Recurrent Diverticulitis in a Patient with Ulcerative Colitis
Get PDFDiverticulitis and ulcerative colitis (UC) are two separate colonic pathologies with different underlying mechanisms. Diverticulosis involves herniation of mucosal and submucosal tissue through muscular tissue in response to increased intraluminal pressure. In contrast, it is believed that the muscular tone in patients with UC is reduced due to chronic inflammatory changes. Thus, it has been reported that there may be an inverse relationship between the presence of diverticulosis in patients with UC, in that UC may possibly be protective against developing diverticular disease. Consequently, the co-presence of both pathologies is uncommon. Here we present a case in which a woman with a history of UC and recurrent diverticulitis after elective partial colectomy was admitted for recurrent acute diverticulitis. It is quite challenging to diagnose diverticulitis in ulcerative colitis patients given the usually similar presentation with abdominal pain, diarrhoea and hematochezia. A level of high suspicion is required for diagnosis
Identification of electrons from B meson decays at the CMS experiment
No full textA new electron reconstruction algorithm has been developed at the CMS experiment to test the lepton flavour universality in B meson decays after the discrepancy with the Standard Model highlighted by the LHCb experiment. In this report, the development and the test of the performance of the identification algorithm for this new type of electrons are presented
Characterization of the JUNO Large-PMT readout electronics
No full textThe Jiangmen Underground Neutrino Observatory (JUNO) is a
neutrino medium baseline experiment under construction in South China, expecting to begin data taking in 2022. JUNO is a liquid-scintillator-based detector with an active target mass of 20 kt; it aims to detect and study electron antineutrinos from reactors to improve the knowledge in the field of neutrino oscillations. The scintillation light emitted by the interaction of an antineutrino in the detector is detected by a system of 17612 20-inch Large-PMTs and 25600 3-inch small-PMTs. The signal from the Large-PMTs is processed by the JUNO Large-PMT readout electronics, which consists of several hardware components and is partly placed underwater. Given the ambitious physics goals of JUNO, the electronic system has to meet specific requirements, and a thorough characterization is required. After describing the readout electronics, tests and results performed with an integration test facility at Laboratori Nazioni di Legnaro, Italy, and at Y-40 The Deep Joy,
Montegrotto Terme (PD) Italy, are here presented and discussed
Liquid argon imaging with Hadamard Masks for neutrino oscillation experiments
No full textLiquid Argon Time Projection Chamber (LArTPC) exploits an
electric field to drift and collect charged particles. The drift time may represent a limitation in high interaction rate environments and a different approach is being developed to overcome such limitation. In this paper the first results obtained with a prototype using such approach are presented
The MUonE experiment
No full textThe latest measurement of the muon g-2, performed by the Muon g-2 Collaboration at Fermilab, presently exhibits a 4.2σ discrepancy from the Standard Model prediction. The hadronic contribution aHLO μ represents the main source
of uncertainty on the theoretical prediction. The MUonE experiment proposes a novel approach to determine aHLO
μ by measuring the running of the electromagnetic coupling constant in the space-like region, via μ−e elastic scattering. The measurement will be performed by scattering a 160 GeV muon beam, currently available at CERN’s North Area, on the atomic electrons of a low-Z target. A Test Run on a reduced detector is planned to validate this proposal. The status of the experiment in view of the Test Run will be presented
High-resolution direct-comb spectrometer at 2.4 μm
No full textWe present the implementation of a direct comb spectrometer
capable of resolving the single-comb mode of a ∼200-MHz pulse repetition rate Cr:ZnSe mode-locked laser at 2.4 μm. The spectrometer is based on the combination of a scanning Fabry-P´erot micro-cavity resonator with a Finesse of 15000 and a diffraction reflecting grating. We demonstrate its application in high-precision spectroscopy of acetylene (C2H2) and deuterated methane (CDH3) at 2.4 μm, over 3 THz bandwidth sampled at 200 MHz and with a frequency resolution of 100 kHz limited only by the comb mode linewidth
On the shoulders of giants: A PCTO experience about Guido da Vigevano
No full textThis report shows the results of a P.C.T.O. (Course for Transversal Skills and Orientation) experience, carried out entirely in DAD (Remote Learning) in the s.y. 2020/2021, involving 100 students from the Scientific and Artistic Secondary School of I.I.S. Cellini, Valenza (AL), Italy. The didactic experience aimed to introduce and spread the important figure of Guido da Vigevano, scientist, doctor and engineer of the 13th/14th century. The entire formative path focused, in particular, on the work Le macchine del re by G. Ostuni, a critical study of the manuscript by Guido da Vigevano Texaurus Regis Francie, which was analyzed by the students from a historical, architectural, engineering, physical and artistic point of view, and encouraged them to think about overcoming the traditional dichotomy existing between humanities and scientific disciplines