ATLAS results on soft diffraction

The measurements of the total inelastic cross section and the differential inelastic cross section as a function of rapidity gap are presented. The data used for these studies were collected in $pp$ collisions at a center-of-mass energy of 7 TeV with the ATLAS detector at the LHC in 2010.Comment: Presented at EDS Blois 2013 (arXiv:1309.5705

The ZDC Detector in ATLAS

The ATLAS Zero Degree Calorimeter (ZDC) is mainly used for studies in heavy-ions physics. It provides information about the collision impact parameter and it is a trigger in ultra-peripheral collisions. ZDC may also detect neutral particles during pp collisions and it is a tool for diffractive physics. We present some preliminary results on ZDC performance for the detection of photons and π0 obtained using pp collisions data

Avaliação de tratamentos para Hepatite com Uso de Antivirais de Ação Direta, em Pacientes Monoinfectados e Coinfectados com HIV, Atendidos no Sistema Único de Saúde, no Período de 2015 a 2018

Tese (doutorado) — Universidade de Brasília, Faculdade de Medicina, Programa de Pós-Graduação em Medicina Tropical, 2021.Introdução: A hepatite C é um grave problema de saúde pública no Brasil e no mundo. As novas terapias com antivirais de ação direta (DAA) representam um grande avanço no tratamento da doença e foram introduzidas no país em 2015. O objetivo deste trabalho foi avaliar a efetividade dos tratamentos da hepatite C com o uso desses antivirais em pacientes monoinfectados e coinfectados com HIV, no período de 2015 a 2018. A taxa de resposta terapêutica positiva é observada após 12 semanas do final do tratamento, por meio do exame de qPCR-HCV indetectável, que indica a resposta virológica sustentada (RVS). Métodos: Foi realizado um estudo de coorte histórica que avaliou a resposta terapêutica dos tratamentos em um total de 11.308 pacientes em uso de esquemas terapêuticos compostos por sofosbuvir (SOF), daclatasvir (DCV), simeprevir (SMV) e associação de ombitasvir, veruprevir/ritonavir e dasabuvir (3D) com ou sem ribavirina (RBV), evidenciando os resultados de exames de PCR quantitativo – qPCR (HCV-RNA) para verificar a resposta virológica sustentada (RVS) após 12 semanas do final do tratamento. Como fontes de dados, foram utilizadas as bases dos sistemas do Departamento de Informática do SUS (DataSus/MS) e do Sistema de Gerenciamento de Ambiente Laboratorial (GAL/MS), no período de 2015 a 2018. Análises de regressão logística foram realizadas para identificar fatores independentemente associados à resposta positiva às terapias baseadas em DAA. Resultados: Entre os pacientes avaliados, 57,1% eram do sexo masculino; 48,3% referiram ser da raça/cor branca; 78,3% tinham mais de 50 anos; 44,1% eram da região Sudeste; 47,7% eram do genótipo 1b; e 84,5% foram tratados por 12 semanas. A taxa de cura, avaliada por tratamento de 12 e 24 semanas, variou de 95,0% a 95,9%, respectivamente. Em comparação com o sexo masculino, as pessoas do sexo feminino apresentaram metade da chance 17 (OR 0,5; IC 95% 0,4-0,6) de ter uma resposta negativa à terapia, e pessoas infectadas com genótipos 2 e 3 tiveram 1,5 vez a chance de não atingir a RVS em comparação com as infectadas com o genótipo 1 (OR 1,5-2,2; IC 95% 0,7- 2,9; e OR 2,7-2,8; IC 95% 2,0-3,8, respectivamente). Pacientes na faixa etária de 50 a 69 anos tiveram 1,2 vez (OR 1,2; IC 95% 0,7-1,9) a chance de não ter RVS em comparação com outras faixas etárias; entretanto, esse dado não se apresentou estatisticamente significativo. Conclusões: Esta pesquisa é a primeira dessa magnitude a ser realizada em um país da América Latina. Os dados obtidos representam as 27 Unidades da Federação do Brasil. Os presentes resultados corroboram outros achados de estudos internacionais e demonstram que a população brasileira tem altas taxas de cura. Considerando o Plano de Eliminação de Hepatite C como problema de saúde pública até 2030, lançado pelo Ministério da Saúde em 2017, é necessário manter a política de tratamento no âmbito da saúde pública para que o país atinja as metas de eliminação.Programa de Apoio à Pós-graduação - PROAP/UnBIntroduction: Hepatitis C is an important public health burden worldwide, including Brazil. New therapies using Direct-Acting Antivirals (DAA) were introduced in the country in 2015 and have greatly advanced the treatment of this disease. The purpose of this study was to evaluate the efficacy of hepatitis C treatment using these antivirals in monoinfected and HIV-coinfected patients, between 2015 and 2018. A positive therapeutic response rate is observed 12 weeks after the end of treatment by testing for undetectable qPCR-HCV, which indicates sustained virological response (SVR). Methods: A historical cohort study assessed the the therapeutic response of treatments in 11,308 patients submitted to the following therapeutic regimens: Sofosbuvir (SOF), Daclatasvir (DCV), Simeprevir (SMV) associated to Ombitasvir, Veruprevir/Ritonavir and Dasabuvir (3D) with or without Ribavirin (RBV), highlighting the results of the quantitative PCR exams – qPCR (HCV- RNA) – to verify sustained virologic response (SVR) twelve weeks after the end of treatment. As data sources, the databases of the SUS IT Department (DataSus/MS) and the Laboratory Environment Management System (GAL/MS) were used in the period from 2015 to 2018. Logistic regression analyses were conducted to identify factors independently associated to a positive response to DAA-based therapies. Results: 57.1% of the patients evaluated were male; 48.3% self-declared as white; 78.3% were over 50 years of age; 44.1% were from the Southeast region; 47.7% carried genotype 1b; and 84.5% were treated for 12 weeks. Cure rates for 12- and 24-week treatments varied from 95.0% to 95.9%, respectively. When compared to male individuals, female patients were half as likely (OR 0.5; CI 95% 0.4-0.6) to have a negative response to therapy, and people infected with genotypes 2 and 3 were 1.5 times more likely to not reach SVR when compared with those infected with genotype 1 (OR 1.5-2.2; CI 95% 0.7-2.9; 1.2-3.6 and OR 2.7-2.8; CI 95% 2,0-3.8, respectively). Patients aged 19 between 50 and 69 years were 1.2 times (OR 1.2; CI 95% 0.7-1.9) more likely to not achieve SVR in comparison to other age groups; however, this result was not found to be statistically significant. Conclusions: the data obtained represent the whole country of Brazil. This research is the first of this magnitude to be carried out in a Latin American country. The data obtained represent the 27 Units of the Federation of Brazil. The study’s results corroborate findings in other international studies and show that the Brazilian population presents high cure rates. Considering the Plan to Eliminate Hepatitis C as a public health threat by 2030, launched by the Ministry of Health in 2017, it is important to keep treatment policies within the public health system to allow Brazil to reach these elimination goals

Day case parathyroidectomy: is this the right way for the patients?

Minimally-invasive video-assisted parathyroidectomy (MIVAP) can be considered as the primary treatment of choice for single parathyroid adenoma. Often, this technique is performed in a day surgery setting and is associated with regional anaesthesia (RA). Many studies have already reported the feasibility and safety of MIVAP in day surgery. Here our focus has been on the patient's personal experience with these procedures through an assessment of their recovery at home

Electron transfer complex between nitrous oxide reductase and cytochrome c552 from Pseudomonas nautica: kinetic, nuclear magnetic resonance, and docking studies

Biochemistry. 2008 Oct 14;47(41):10852-62. doi: 10.1021/bi801375qThe multicopper enzyme nitrous oxide reductase (N 2OR) catalyzes the final step of denitrification, the two-electron reduction of N 2O to N 2. This enzyme is a functional homodimer containing two different multicopper sites: CuA and CuZ. CuA is a binuclear copper site that transfers electrons to the tetranuclear copper sulfide CuZ, the catalytic site. In this study, Pseudomonas nautica cytochrome c 552 was identified as the physiological electron donor. The kinetic data show differences when physiological and artificial electron donors are compared [cytochrome vs methylviologen (MV)]. In the presence of cytochrome c 552, the reaction rate is dependent on the ET reaction and independent of the N 2O concentration. With MV, electron donation is faster than substrate reduction. From the study of cytochrome c 552 concentration dependence, we estimate the following kinetic parameters: K m c 552 = 50.2 +/- 9.0 muM and V max c 552 = 1.8 +/- 0.6 units/mg. The N 2O concentration dependence indicates a K mN 2 O of 14.0 +/- 2.9 muM using MV as the electron donor. The pH effect on the kinetic parameters is different when MV or cytochrome c 552 is used as the electron donor (p K a = 6.6 or 8.3, respectively). The kinetic study also revealed the hydrophobic nature of the interaction, and direct electron transfer studies showed that CuA is the center that receives electrons from the physiological electron donor. The formation of the electron transfer complex was observed by (1)H NMR protein-protein titrations and was modeled with a molecular docking program (BiGGER). The proposed docked complexes corroborated the ET studies giving a large number of solutions in which cytochrome c 552 is placed near a hydrophobic patch located around the CuA center

A new CuZ active form in the catalytic reduction of N2O by nitrous oxide reductase from Pseudomonas nautica

J Biol Inorg Chem (2010) 15:967–976 DOI 10.1007/s00775-010-0658-6The final step of bacterial denitrification, the two-electron reduction of N2O to N2, is catalyzed by a multi-copper enzyme named nitrous oxide reductase. The catalytic centre of this enzyme is a tetranuclear copper site called CuZ, unique in biological systems. The in vitro reconstruction of the activity requires a slow activation in the presence of the artificial electron donor, reduced methyl viologen, necessary to reduce CuZ from the resting non-active state (1CuII/3CuI) to the fully reduced state (4CuI), in contrast to the turnover cycle, which is very fast. In the present work, the direct reaction of the activated form of Pseudomonas nautica nitrous oxide reductase with stoichiometric amounts of N2O allowed the identification of a new reactive intermediate of the catalytic centre, CuZ°, in the turnover cycle, characterized by an intense absorption band at 680 nm. Moreover, the first mediated electrochemical study of Ps. nautica nitrous oxide reductase with its physiological electron donor, cytochrome c-552, was performed. The intermolecular electron transfer was analysed by cyclic voltammetry, under catalytic conditions, and a second-order rate constant of (5.5 ± 0.9) × 105 M−1 s−1 was determined. Both the reaction of stoichiometric amounts of substrate and the electrochemical studies show that the active CuZ° species, generated in the absence of reductants, can rearrange to the resting non-active CuZ state. In this light, new aspects of the catalytic and activation/inactivation mechanism of the enzyme are discussed

New detailed characterization of the residual luminescence emitted by the GAGG:Ce scintillator crystals for the HERMES Pathfinder mission

The HERMES (High Energy Rapid Modular Ensemble of Satellites) Pathfinder mission aims to develop a constellation of nanosatellites to study astronomical transient sources, such as gamma-ray bursts, in the X and soft $\gamma$ energy range, exploiting a novel inorganic scintillator. This study presents the results obtained describing, with an empirical model, the unusually intense and long-lasting residual emission of the GAGG:Ce scintillating crystal after irradiating it with high energy protons (70 MeV) and ultraviolet light ($\sim$ 300 nm). From the model so derived, the consequences of this residual luminescence for the detector performance in operational conditions has been analyzed. It was demonstrated that the current generated by the residual emission peaks at 1-2 pA, thus ascertaining the complete compatibility of this detector with the HERMES Pathfinder nanosatellites

Hunt for new phenomena using large jet multiplicities and missing transverse momentum with ATLAS in 4.7 fb−1 of s√=7TeV proton-proton collisions

Results are presented of a search for new particles decaying to large numbers of jets in association with missing transverse momentum, using 4.7 fb−1 of pp collision data at s√=7TeV collected by the ATLAS experiment at the Large Hadron Collider in 2011. The event selection requires missing transverse momentum, no isolated electrons or muons, and from ≥6 to ≥9 jets. No evidence is found for physics beyond the Standard Model. The results are interpreted in the context of a MSUGRA/CMSSM supersymmetric model, where, for large universal scalar mass m 0, gluino masses smaller than 840 GeV are excluded at the 95% confidence level, extending previously published limits. Within a simplified model containing only a gluino octet and a neutralino, gluino masses smaller than 870 GeV are similarly excluded for neutralino masses below 100 GeV

Search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at s√=8 TeV with the ATLAS detector

The results of a search for direct pair production of the scalar partner to the top quark using an integrated luminosity of 20.1fb−1 of proton–proton collision data at √s = 8 TeV recorded with the ATLAS detector at the LHC are reported. The top squark is assumed to decay via t˜→tχ˜01 or t˜→ bχ˜±1 →bW(∗)χ˜01 , where χ˜01 (χ˜±1 ) denotes the lightest neutralino (chargino) in supersymmetric models. The search targets a fully-hadronic final state in events with four or more jets and large missing transverse momentum. No significant excess over the Standard Model background prediction is observed, and exclusion limits are reported in terms of the top squark and neutralino masses and as a function of the branching fraction of t˜ → tχ˜01 . For a branching fraction of 100%, top squark masses in the range 270–645 GeV are excluded for χ˜01 masses below 30 GeV. For a branching fraction of 50% to either t˜ → tχ˜01 or t˜ → bχ˜±1 , and assuming the χ˜±1 mass to be twice the χ˜01 mass, top squark masses in the range 250–550 GeV are excluded for χ˜01 masses below 60 GeV

Measurement of the top pair production cross section in 8 TeV proton-proton collisions using kinematic information in the lepton plus jets final state with ATLAS

A measurement is presented of the $t\bar{t}$ inclusive production cross-section in $pp$ collisions at a center-of-mass energy of $\sqrt{s}=8$ TeV using data collected by the ATLAS detector at the CERN Large Hadron Collider. The measurement was performed in the lepton+jets final state using a data set corresponding to an integrated luminosity of 20.3 fb$^{-1}$. The cross-section was obtained using a likelihood discriminant fit and $b$-jet identification was used to improve the signal-to-background ratio. The inclusive $t\bar{t}$ production cross-section was measured to be $260\pm 1{\textrm{(stat.)}} ^{+22}_{-23} {\textrm{(syst.)}}\pm 8{\textrm{(lumi.)}}\pm 4{\mathrm{(beam)}}$ pb assuming a top-quark mass of 172.5 GeV, in good agreement with the theoretical prediction of $253^{+13}_{-15}$ pb. The $t\bar{t}\to (e,\mu)+{\mathrm{jets}}$ production cross-section in the fiducial region determined by the detector acceptance is also reported.Comment: Published version, 19 pages plus author list (35 pages total), 3 figures, 2 tables, all figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/TOPQ-2013-06