A joint experimental and theoretical study on the electronic structure and photoluminescence properties of Al2(WO4)3 powders

In this paper, aluminum tungstate Al2(WO4)3 powders were synthesized using the co-precipitation method at room temperature and then submitted to heat treatment processes at different temperatures (100, 200, 400, 800, and 1000 °C) for 2 h. The structure and morphology of the powders were characterized by means of X-ray diffraction (XRD), Rietveld refinement data, and field emission scanning electron microscopy (FE-SEM) images. Their optical properties were examined with ultraviolet-visible (UV-vis) diffuse reflectance spectroscopy and photoluminescence (PL) measurements. XRD patterns and Rietveld refinement data showed that Al2(WO4)3 powders heat treated at 1000 °C for 2 h have a orthorhombic structure with a space group (Pnca) without the presence of deleterious phases. FE-SEM images revealed that these powders are formed by the aggregation of several nanoparticles leading to the growth of microparticles with irregular morphologies and an agglomerated nature. UV-vis spectra indicated that optical band gap energy increased from 3.16 to 3.48 eV) as the processing temperature rose, which was in turn associated with a reduction in intermediary energy levels. First-principle calculations were performed in order to understand the behavior of the PL properties using density functional theory at the B3LYP calculation level on periodic model systems and indicate the presence of stable electronic excited states (singlet). The analyses of the band structures and density of states at both ground and first excited electronic states provide insight into the main features, based on structural and electronic order-disorder effects in octahedral [AlO6] clusters and tetrahedral [WO4] clusters, as constituent building units of this material

Zonificación, identificación de áreas de interés para la conservación y propuesta de criterios para el establecimiento de límites funcionales en el complejo ventana piloto de humedales Paz de Ariporo- Hato Corozal.

Este documento es resultado de la ejecución del Contrato 14-13-014-237PS entre el Instituto Humboldt y la Fundación Omacha, firmado en el marco del Convenio 005 (13-014) entre el Instituto Humboldt y el Fondo Adaptación. Contiene la propuesta para la identificación del límite funcional de la ventana piloto de humedales Paz de Ariporo- Hato Corozal, el cual consistió en un ejercicio de zonación de los humedales, identificación de los hábitos de crecimiento y alimentarios, como también en la descripción de otros procesos ecológicos que interactuaban con el paisaje de acuerdo con el gradiente transicional, desde el cuerpo de agua hasta tierra firme.BogotáSubdirección de Servicios Científicos y Proyectos Especiale

Implicações da radiação na saúde dos profissionais que utilizam a fluoroscopia na prática diária: Implications of radiation on the health of professionals who use the fluoroscopy in daily practice

O presente estudo tem como objetivo analisar as implicações da radiação na saúde dos profissionais que utilizam o arco cirúrgico na prática diária. Neste estudo foi realizada uma revisão sistemática da literatura. Para seleção das publicações foram considerados como critérios de inclusão estar disponível em formato completo, publicado nos últimos cinco anos (2018-2022), escritas em língua portuguesa e inglesa. E como critérios de exclusão foram considerados estar foram do tema de pesquisa, ser revisão de literatura e repetido na base de dados. Os critérios de inclusão e exclusão foram considerados como meio de validade metodológica. Concluiu-se a partir desse estudo que apesar de baixos níveis de radiação emitidos por arco cirúrgico, os riscos ainda são significativos, verificando-se a necessidade de conscientização dos profissionais de saúde sobre a proteção necessária para mitigação das implicações, principalmente, entre os menos experientes.&nbsp

Uma abordagem acerca da Influenza A-H1N1 e a pandemia de Covid-19 no contexto brasileiro: uma revisão integrativa / An approach to Influenza A-H1N1 in the Brazilian context: an integrative review

O presente estudo tem como objetivo relatar os aspectos da influenza A-H1N1, dentre eles a caracterização viral, diagnóstico e prevenção. Ademais, objetivou-se na abordagem o papel dos suínos na transmissão interespécie e a epidemiologia da doença no Brasil, bem como as semelhanças da doença com a COVID-19, que apresentam um desafio para a saúde pública do país. Trata-se de uma revisão integrativa da literatura realizada através da Biblioteca Virtual em Saúde (BVS), com o auxílio das bases de dados Literatura Latino-Americana e do Caribe em Ciências (LILACS), Scientific Library Eletronic Library Online (SciELO) e Base de Dados de Enfermagem (BDENF), sendo utilizados os descritores: Brasil; COVID-19; Epidemiologia; Patologia e Vírus da influenza A subtipo H1N1, localizados no DeCS. Tais descritores foram cruzados utilizando o operador booleano AND. Foram identificados inicialmente 736 estudos nas bases elencas e, após aplicação dos critérios de inclusão e exclusão, apenas 06 estudos foram selecionados para composição e análise do estudo. Os estudos apontam a sintomatologia ocasionada pelos vírus da Influenza A-H1N1 e COVID-19é semelhante, assim como a forma de transmissão e o agravamento ocasionado pela presença eventual de doenças prévias. A diferenciação se encontra no período de incubação, sendo de 3 a 7 dias no caso da influenza e de 2 a 14 dias na COVID-19. Conclui-se que no contexto pandêmico atual envolvendo o vírus SARS-CoV-2 exige um maior monitoramento, uma vez que as enfermidades possuem semelhanças que podem levar a confusão e dificultar o atendimento

Pseudorapidity and transverse momentum dependence of flow harmonics in pPb and PbPb collisions

info:eu-repo/semantics/publishe

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Identification of heavy-flavour jets with the CMS detector in pp collisions at 13 TeV

Many measurements and searches for physics beyond the standard model at the LHC rely on the efficient identification of heavy-flavour jets, i.e. jets originating from bottom or charm quarks. In this paper, the discriminating variables and the algorithms used for heavy-flavour jet identification during the first years of operation of the CMS experiment in proton-proton collisions at a centre-of-mass energy of 13 TeV, are presented. Heavy-flavour jet identification algorithms have been improved compared to those used previously at centre-of-mass energies of 7 and 8 TeV. For jets with transverse momenta in the range expected in simulated $\mathrm{t}\overline{\mathrm{t}}$ events, these new developments result in an efficiency of 68% for the correct identification of a b jet for a probability of 1% of misidentifying a light-flavour jet. The improvement in relative efficiency at this misidentification probability is about 15%, compared to previous CMS algorithms. In addition, for the first time algorithms have been developed to identify jets containing two b hadrons in Lorentz-boosted event topologies, as well as to tag c jets. The large data sample recorded in 2016 at a centre-of-mass energy of 13 TeV has also allowed the development of new methods to measure the efficiency and misidentification probability of heavy-flavour jet identification algorithms. The heavy-flavour jet identification efficiency is measured with a precision of a few per cent at moderate jet transverse momenta (between 30 and 300 GeV) and about 5% at the highest jet transverse momenta (between 500 and 1000 GeV)

Search for heavy resonances decaying to a top quark and a bottom quark in the lepton+jets final state in proton–proton collisions at 13 TeV

info:eu-repo/semantics/publishe

Evidence for the Higgs boson decay to a bottom quark–antiquark pair

info:eu-repo/semantics/publishe

Particle-flow reconstruction and global event description with the CMS detector

The CMS apparatus was identified, a few years before the start of the LHC operation at CERN, to feature properties well suited to particle-flow (PF) reconstruction: a highly-segmented tracker, a fine-grained electromagnetic calorimeter, a hermetic hadron calorimeter, a strong magnetic field, and an excellent muon spectrometer. A fully-fledged PF reconstruction algorithm tuned to the CMS detector was therefore developed and has been consistently used in physics analyses for the first time at a hadron collider. For each collision, the comprehensive list of final-state particles identified and reconstructed by the algorithm provides a global event description that leads to unprecedented CMS performance for jet and hadronic tau decay reconstruction, missing transverse momentum determination, and electron and muon identification. This approach also allows particles from pileup interactions to be identified and enables efficient pileup mitigation methods. The data collected by CMS at a centre-of-mass energy of 8 TeV show excellent agreement with the simulation and confirm the superior PF performance at least up to an average of 20 pileup interactions