17 research outputs found

    Análise comparativa das propriedades de óxidos transparentes condutores para aplicação em células solares de filmes finos de CdTe

    Get PDF
    Este trabalho compara as propriedades de diversos óxidos transparentes condutores para serem utilizadoscomo contatos frontais de células solares de filmes finos de CdTe. Os filmes foram depositados à temperaturaambiente, por pulverização catódica com rádio frequência, sem tratamento térmico posterior, com o objetivode reduzir o número de etapas do processo de fabricação. A relação resistência/transmitância foi avaliadaatravés de uma figura de mérito, de forma a propor os materiais candidatos a atuar como eletrodo frontal dacélula solar. Os óxidos investigados foram divididos em dois grupos: os de baixa resistividade e os de altaresistividade. Eletrodos fabricados com os diversos óxidos foram submetidos a testes de estabilidade térmicanas temperaturas de processamento da célula solar. Os resultados mostraram que os filmes de ZnO e Zn2SnO4são óxidos de alta resistividade ( 0,5 ï—.cm), enquanto que os de SnO2, In2O3, In2O3:Sn, Cd2SnO4 e ZnO:Alsão de baixa resistividade ( 5,0 x 10-3 ï—.cm) e alta transmitância ( 85%). Os filmes de In2O3:Sn e ZnO:Alapresentaram-se como as melhores opções para fabricação dos eletrodos, pois possuem resistividades na faixade 10-3--10-4 ï—.cm e transmitâncias entre 85-92%. No entanto, levando-se em consideração questões decusto e escassez associadas ao índio, filmes de ZnO:Al são os mais adequados para esta aplicação, pois alémde possuírem valores de condutividade e transmitância elevados, apresentaram elevada estabilidade térmicanas temperaturas de processamento da célula

    Eficácia de intervenções imunomoduladoras para o tratamento da Esclerose Lateral Amiotrófica (ELA)

    Get PDF
    A esclerose lateral amiotrófica (ELA) é uma doença neurodegenerativa que afeta as células nervosas responsáveis pelo controle dos músculos voluntários, resultando em fraqueza muscular e atrofia. Nesse contexto, as intervenções imunomoduladoras têm como objetivo modular a resposta imune do organismo, ao reduzir a inflamação e possibilitar a neuroproteção, a partir do uso de anticorpos monoclonais, inibidores de citocinas e moduladores do sistema imunológico. No entanto, a eficácia de tais intervenções no tratamento da ELA ainda é incerta. Nesse sentido, o presente estudo tem como objetivo analisar a eficácia de intervenções imunomoduladoras para o tratamento da esclerose lateral amiotrófica. Para isso, foram selecionados cinco artigos que abordavam sobre a sua eficácia, por meio de uma estratégia de busca com recorte temporal entre 2017 e 2023, nas bases de dados PubMed (Medline), Cochrane Library e Embase. As intervenções imunomoduladoras, como o uso de inibidores de citocinas, têm demonstrado eficácia no tratamento da esclerose lateral amiotrófica (ELA). Além disso, há evidências de que a inflamação crônica pode estar envolvida em sua patogênese, o que sugere que a modulação do sistema imunológico pode ser uma abordagem terapêutica promissora. Em estudos clínicos recentes, a terapia com inibidores de citocinas mostrou-se capaz de reduzir a progressão da doença e melhorar a qualidade de vida dos pacientes com ELA. Ademais, há evidências que o uso de células-tronco pode melhorar o status funcional em pacientes com a doença. Entretanto, são necessários mais estudos, como ensaios clínicos randomizados e revisões sistemáticas com meta-análises, a fim de ratificar a eficácia das estratégias imunomoduladoras para a patologia

    2 nd Brazilian Consensus on Chagas Disease, 2015

    Full text link
    Abstract Chagas disease is a neglected chronic condition with a high burden of morbidity and mortality. It has considerable psychological, social, and economic impacts. The disease represents a significant public health issue in Brazil, with different regional patterns. This document presents the evidence that resulted in the Brazilian Consensus on Chagas Disease. The objective was to review and standardize strategies for diagnosis, treatment, prevention, and control of Chagas disease in the country, based on the available scientific evidence. The consensus is based on the articulation and strategic contribution of renowned Brazilian experts with knowledge and experience on various aspects of the disease. It is the result of a close collaboration between the Brazilian Society of Tropical Medicine and the Ministry of Health. It is hoped that this document will strengthen the development of integrated actions against Chagas disease in the country, focusing on epidemiology, management, comprehensive care (including families and communities), communication, information, education, and research

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

    Get PDF
    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Characterization Of Cigs Thin Film Solar Cells

    No full text
    Photovoltaic solar energy is presently a consolidated market. The annual growth rate of global photovoltaic installations was 40% in 2010-2016, a milestone hardly achieved by any other segment of the technology industry. Silicon based technology accounted for 94% of the total production in 2016, while the market share of thin film technology was 6%. One of the materials used in the thin film photovoltaic market is copper in-dium gallium di-selenide (CIGS). This work presents the preliminary results of a collaborative program be-tween Florida Solar Energy Center and Instituto Militar de Engenharia aiming the fabrication and characteri-zation of CIGS thin film solar cells. The solar devices were fabricated at Florida Solar Energy Center with the configuration glass/Mo/CIGS/CdS/ZnO/ZnO:Al/metal and were characterized at Instituto Militar de Engenharia from the current x voltage and quantum efficiencies curves. The highest efficiency was 3.8%. The results showed that the efficiency was limited by the low values of fill factor and open circuit voltage. Parallel and series resistances limited the fill factor. The lack of the alkali post treatment and the low quantity of gallium in the CIGS film limited the open circuit voltage. The results also suggest that the thickness of the cadmium sulfide layer is nonuniform, probably due to the swirling occasioned by excessively stirring of the precursor solution during the chemical bath deposition

    Microstructural Characterization of a 1200 MPa Complex-Phase Steel

    No full text
    The demand for new advanced high strength steels (AHSS) has been increasing in the last few decades. A large part of this demand comes from automotive companies. We have produced a new complex-phase (CP) steel with 1200 MPa of mechanical resistance and 8% of elongation, called CP1200. In this paper the dilatometric and microstructural characterization of a newly produced CP1200 steel is presented. The new steel was produced by making changes to the heat treatment of the already industrially available CP1100. The microstructure was quantified using light optical microscopy (LOM) and electron backscatter diffraction (EBSD). The microstructure of both steels was compared to identify the origin of the mechanical properties improvement. A new microstructure distribution, with higher amount of bainite and smaller concentration of ferrite and martensite was identified.</p

    Characterization of CIGS thin film solar cells

    No full text
    <p></p><p>ABSTRACT Photovoltaic solar energy is presently a consolidated market. The annual growth rate of global photovoltaic installations was 40% in 2010-2016, a milestone hardly achieved by any other segment of the technology industry. Silicon based technology accounted for 94% of the total production in 2016, while the market share of thin film technology was 6%. One of the materials used in the thin film photovoltaic market is copper indium gallium di-selenide (CIGS). This work presents the preliminary results of a collaborative program between Florida Solar Energy Center and Instituto Militar de Engenharia aiming the fabrication and characterization of CIGS thin film solar cells. The solar devices were fabricated at Florida Solar Energy Center with the configuration glass/Mo/CIGS/CdS/ZnO/ZnO:Al/metal and were characterized at Instituto Militar de Engenharia from the current x voltage and quantum efficiencies curves. The highest efficiency was 3.8%. The results showed that the efficiency was limited by the low values of fill factor and open circuit voltage. Parallel and series resistances limited the fill factor. The lack of the alkali post treatment and the low quantity of gallium in the CIGS film limited the open circuit voltage. The results also suggest that the thickness of the cadmium sulfide layer is nonuniform, probably due to the swirling occasioned by excessively stirring of the precursor solution during the chemical bath deposition.</p><p></p

    Phytochemical bioprospecting, antioxidant, antimicrobial and cytotoxicity activities of saline extract from Tithonia diversifolia (Hemsl) A. Gray leaves

    No full text
    Objective: To evaluate antimicrobial and antioxidant properties of saline extract from Tithonia diversifolia leaves by phytochemical bioprospecting, and investigate its safety against animal cells. Methods: The saline extract was prepared, with NaCl (0.15 M), by constant stirring of the dried and pulverized leaves, followed by volume reduction by lyophilization. The extract was phytochemical characterized using ultra-performance liquid chromatography, and total phenol and flavonoid analysis also was performed. The antioxidant capacity was determined through DPPH· radical, the antimicrobial property was evaluated against standard bacteria and fungi, and the viability assays were performed against mice splenocytes. Results: Fifteen compounds were identified belonging to two main classes terpenoids and phenolics. The extract showed 22.185 mg GAE/g of total phenolic compounds and 3.220 mg QE/g of flavonoid. Moreover, extract showed higher antioxidant ability similar to butylated hydroxytoluene a standard molecule [(3.042±0.019) mg AAE/g and (4.12±0.10) mg AAE/g to saline extract and butylated hydroxytoluene, respectively]. The antimicrobial assays demonstrated that the extract had a significant antifungal potential against Candida species and could be used with safety against mice splenocytes, in concentrations lower than 50 μg/mL, promoting higher proliferation in these cells. Conclusions: Saline extract from Tithonia diversifolia leaves presents potential antioxidant, antifungal properties and induces immunostimulation in mice splenocytes
    corecore