Estudo teórico das propriedades eletrônicas e estruturais do mecanismo de adsorção de íons metálicos com a matriz de vanilina

The density method was used to understand the adsorption process of Cd2+, Cr3+, Cu2+, Hg2+ , Pb2+ and Zn2+ ions with the methacrylate monomer. of Vanillin. All data is related to the stability of the students studied using Gaussian09 software download tools. The conformations are possible to be studied using the energy minima. Several analyzes were carried out: Conformational analysis, molecular electrostatic potential (MEP) map, adsorption energy, boundary orbitals, hardness and softness, all of which are necessary for the prediction of complex formation. To date, one of the adsorption sites has been studied in which each was one of the major nitrogen and oxygen instruments of the imine and carboxyl groups in contact with the nitrogen atoms. Percentage of oxygen emission because the rate of nitrogen loading is increased in the formation of Schiff's base with the proximity of the aromatic. The monomer showed to be more adsorbent for the Cu (II) and Cr (III) ions because of the high energy values involved, and according to the calculations in QTAIM, the vanillin was added with a covalent partial character. The monomer derived from vanillin shows good stability against the aqueous medium and the presence of metals is a good material for the remediation of effluents, however it did not show good adsorbent for Cd (II) and Zn (II) ions.Foi utilizado a teoria do funcional de densidade para compreender o processo de adsorção dos íons Cd(II), Cr (III), Cu (II), Hg (II), Pb (II) e Zn (II) com o monômero metacrilato derivado da Vanilina. Todas as de propriedades estruturais e efeitos estereoeletrônicos dos complexos estudados foram analisados utilizando-se o programa Gaussian09 e a teoria QTAIM. As conformações possíveis do adsorvente foram estudadas usando os mínimos de energia. Realizaram-se diferentes análises: Análise conformacional, mapa de potencial eletrostático (MPE), energia de adsorção, orbitais de fronteira, dureza e moleza sendo todas necessárias para predição da formação dos complexos. Por meio da análise de mapa de potencial eletrostático e orbitais de fronteira, (FMOs) a melhor região para adsorção foi encontrada, assim cada íon metálico do estudo foi colocado próximos dos átomos de nitrogênio e oxigênio dos grupos imina e carboxila, respectivamente. A ligação dos íons metálicos com o átomo de nitrogênio se mostrou mais forte do que com átomos de oxigênio, pois, a densidade de carga do nitrogênio é aumentada na formação da base de Schiff com a proximidade do anel aromático. O monômero se mostrou melhor adsorvente para os íons Cu (II) e Cr (III) por conta dos altos valores de energias envolvidos, e que segundo os cálculos em QTAIM se ligaram a vanilina com caráter parcial covalente. O monômero derivado da vanilina apresenta boa estabilidade frente ao meio aquoso e a presença dos metais sendo assim um bom material para a remediação de efluentes, no entanto, não se mostrou bom adsorvente para os íons Cd (II) e Zn(II)

The Changing Landscape for Stroke\ua0Prevention in AF: Findings From the GLORIA-AF Registry Phase 2

Background GLORIA-AF (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation) is a prospective, global registry program describing antithrombotic treatment patterns in patients with newly diagnosed nonvalvular atrial fibrillation at risk of stroke. Phase 2 began when dabigatran, the first non\u2013vitamin K antagonist oral anticoagulant (NOAC), became available. Objectives This study sought to describe phase 2 baseline data and compare these with the pre-NOAC era collected during phase 1. Methods During phase 2, 15,641 consenting patients were enrolled (November 2011 to December 2014); 15,092 were eligible. This pre-specified cross-sectional analysis describes eligible patients\u2019 baseline characteristics. Atrial fibrillation disease characteristics, medical outcomes, and concomitant diseases and medications were collected. Data were analyzed using descriptive statistics. Results Of the total patients, 45.5% were female; median age was 71 (interquartile range: 64, 78) years. Patients were from Europe (47.1%), North America (22.5%), Asia (20.3%), Latin America (6.0%), and the Middle East/Africa (4.0%). Most had high stroke risk (CHA2DS2-VASc [Congestive heart failure, Hypertension, Age  6575 years, Diabetes mellitus, previous Stroke, Vascular disease, Age 65 to 74 years, Sex category] score  652; 86.1%); 13.9% had moderate risk (CHA2DS2-VASc = 1). Overall, 79.9% received oral anticoagulants, of whom 47.6% received NOAC and 32.3% vitamin K antagonists (VKA); 12.1% received antiplatelet agents; 7.8% received no antithrombotic treatment. For comparison, the proportion of phase 1 patients (of N = 1,063 all eligible) prescribed VKA was 32.8%, acetylsalicylic acid 41.7%, and no therapy 20.2%. In Europe in phase 2, treatment with NOAC was more common than VKA (52.3% and 37.8%, respectively); 6.0% of patients received antiplatelet treatment; and 3.8% received no antithrombotic treatment. In North America, 52.1%, 26.2%, and 14.0% of patients received NOAC, VKA, and antiplatelet drugs, respectively; 7.5% received no antithrombotic treatment. NOAC use was less common in Asia (27.7%), where 27.5% of patients received VKA, 25.0% antiplatelet drugs, and 19.8% no antithrombotic treatment. Conclusions The baseline data from GLORIA-AF phase 2 demonstrate that in newly diagnosed nonvalvular atrial fibrillation patients, NOAC have been highly adopted into practice, becoming more frequently prescribed than VKA in Europe and North America. Worldwide, however, a large proportion of patients remain undertreated, particularly in Asia and North America. (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients With Atrial Fibrillation [GLORIA-AF]; NCT01468701

Theoretical study of the internal rotational barriers of fluorine, chlorine, bromine, and iodine-substituted ethanes

Physical and chemical characteristics of flexible compounds are extremely dependent of internal rotation barriers. On the other hand, halides of organic compounds are extremely common, and the nature of their rotation barriers are still poorly understood. As a simple example, the experimental height of the internal rotational barrier decreases with the number of fluorine-substituted in ethane, C2H5F, C2H4F2, and C2H3F3. For chlorinesubstituted ethane C2H5CI, C2H4Cl2 and C2H3Cl3 the internal rotational barrier converges in an opposite manner. No experimental results are available for the bromine- and iodine-substituted compounds C2H5Br, C2H4Br2, C2H3Br3, C2H5I, C2H4I2, and C2H3I3. In light of lack of both an adequate explanation for this phenomenon and experimental results for Br and I, the present work studied these compounds using different levels of theory: MP2, MP3, MP4, QCISD(T) and CCSD(T) methods, and the G3 and G3CEP composite theories. The results showed that the G3 and G3CEP theories were the most accurate calculations for the F- and Cl-substituted compounds as a result of the additive contributions of the energy values. From Natural Bond Orbitals (NBO), Quantum Theory of Atoms in Molecules (QTAIM) and Energy Decomposition Analysis (EDA) it was verified that the internal rotational barriers decrease with the addition of Fluorine atoms for fluorine-containing ethanes and can be explained by: pi character in the C-F bond and delocalization indexes (DI(A)) by QTAIM analysis; the interaction of the ligand and anti-ligand orbitals by NBO analysis and for the descriptors by EDA. On the other hand, the enlargement of the barriers with the addition of Cl, Br and I atoms for substituted ethanes, are dominated by the large electronic cloud of these halogens, which generates significant steric repulsion1166COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPnão tem2013/08293-7; 2017/11485-6The authors acknowledges the National Center for High Performance Processing (Centro Nacional de Processamento de Alto Desempenho – CENAPAD) in São Paulo, UNICAMP (Universidade de Campinas), for computational resources. The authors would like to thank FAPESP (Fundação de Amparo à Pesquisa do Estado de São Paulo - Center for Computational Engineering and Sciences, Grant 2013/08293-7, and Grant 2017/11485-6). D.H. Pereira also acknowledges funding from CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Coordination of Improvement of Higher Education Personnel - Brazil), Funding Code 001 CAPES, and the UFT New Researchers Program (Programa Novos Pesquisadores da Universidade Federal do Tocantins - PROPESQ/UFT