406 research outputs found

    The golden fig: a plasmonic effect study of organic-based solar cells

    Get PDF
    An optimization work on dye-sensitized solar cells (DSSCs) based on both artificial and natural dyes was carried out by a fine synthesis work embedding gold nanoparticles in a TiO(2) semiconductor and perfecting the TiO(2) particle sizes of the scattering layer. Noble metal nanostructures are known for the surface plasmon resonance peculiarity that reveals unique properties and has been implemented in several fields such as sensing, photocatalysis, optical antennas and PV devices. By embedding gold nanoparticles in the mesoporous TiO(2) layer and adding a scattering layer, we were able to boost the power conversion efficiency (PCE) to 10.8%, using an organic ruthenium complex. The same implementation was carried out using a natural dye, betalains, extracted from Sicilian prickly pear. In this case, the conversion efficiency doubled from 1 to 2% (measured at 1 SUN illumination, 100 mW/cm(2) under solar simulation irradiation). Moreover, we obtained (measured at 0.1 SUN, 10 mW/cm(2) under blue light LED irradiation) a record efficiency of 15% with the betalain-based dye, paving the way for indoor applications in organic natural devices. Finally, an attempt to scale up the system is shown, and a betalain-based- dye-sensitized solar module (DSSM), with an active area of 43.2 cm(2) and a PCE of 1.02%, was fabricated for the first time

    Capacidade funcional e qualidade de vida de adultos e idosos com feridas crônicas

    Get PDF
    Introdução: As feridas crônicas afetam a população em geral e comprometem negativamente a qualidade de vida e geram impactos biopsicossociais. Objetivo: Analisar a associação entre a capacidade funcional e a qualidade de vida de adultos e idosos com feridas crônicas. Métodos: Estudo transversal com 135 acometidas por feridas crônicas cadastradas nos serviços de atenção primária à saúde de um município de Minas Gerais, Brasil. Para a coleta dedados realizada no período de 2017 a 2018, utilizaram-se os instrumentos i) Cardiff Wound Impact Schedule que foi traduzido, adaptado culturalmente e validado para a língua portuguesa do Brasil; ii) Índice de Katz e iii) questionáriosociodemográfico com informações sobre o perfil de saúde/doença e características das feridas. Resultados: Houve predomínio de participantes do sexo feminino (59,3%), com idade acima de 60 anos (70,4%) e até 4 anos de estudo (72,6%). No questionário Cardiff Wound Impact Schedule, o domínio com menor pontuação foi o debem-estar (média 45,6 ± 18,2). Na avaliação da funcionalidade realizada por meio do Índice de Katz, destaca-se que 30 (22,2%) pessoas foram consideradas dependentes para tomar banho e 33 (24,4%) necessitavam de ajuda para se locomover. Houve associação estatisticamente significativa entre as seguintes variáveis independentes do Índice de Katz e do Cardiff Wound Impact Schedule para “vida social” e “banho”, “vida social” e “vestir-se”, “vidasocial” e “higiene pessoal”, “vida social” e “locomoção”, “vida social” e “alimentação”, “sintomas físicos e vida diária” e “vestir-se”, “bem-estar” e “continência”. Conclusão: A incapacidade funcional está associada à diminuição da qualidade de vida de adultos e idosos com feridas crônicas.Introduction. Wounds affect the general population and negatively compromise the quality of life and generate biopsychosocial impacts. Objective. Analyze the association between functional capacity and quality of life in adults and elderly people with chronic wounds. Methods. Cross-sectional study with 135 people with chronic wounds registered in the primary health care services of a municipality in Minas Gerais, Brazil. For data collection carriedout from 2017 to 2018, the following were used: i) Cardiff Wound Impact Schedule, which was translated, culturally adapted and validated for the Brazilian Portuguese language; ii) Katz Index and iii) a sociodemographic questionnaire with information about the health/illness profile and injury characteristics. Results. There was a predominanceof female participants (59.3%), aged over 60 years (70.4%), and until 4 years of study (72.6%). In the Cardiff Wound Impact Schedule questionnaire, the domain with the lowest score was well-being (mean 45.6 ± 18.2). In the evaluation of functionality using the Katz Index, 30 (22.2%) people were considered dependent on bathing and 33 (24.4%) needed help to get around. There was a statistically significant association between the following independent variables of the Katz Index and Cardiff Wound Impact Schedule for “social life” and “bathing”, “sociallife” and “dressing”, “social life” and “personal hygiene”, “social life” and “locomotion”, “social life” and “feeding”, “physical symptoms and daily life” and “dressing”, “well-being” and “continence”. Conclusions. Functional disability is associated with decreased quality of life in adults and elderly people with chronic wounds

    Guideline on carotid surgery for stroke prevention: updates from the Italian Society of Vascular and Endovascular Surgery. A trend towards personalized medicine

    Get PDF
    Background: This guideline (GL) on carotid surgery as updating of "Stroke: Italian guidelines for Prevention and Treatment" of the ISO-SPREAD Italian Stroke Organization-Group, has recently been published in the National Guideline System and shared with the Italian Society of Vascular and Endovascular Surgery (SICVE) and other Scientific Societies and Patient's Association. Methods: GRADE-SIGN version, AGREE quality of reporting checklist. Clinical questions formulated according to the PICO model. Recommendations developed based on clinical questions by a multidisciplinary experts' panel and patients' representatives. Systematic reviews performed for each PICO question. Considered judgements filled by assessing the evidence level, direction, and strength of the recommendations. Results: The panel provided indications and recommendations for appropriate, comprehensive, and individualized management of patients with carotid stenosis. Diagnostic and therapeutic processes of the best medical therapy, carotid endarterectomy (CEA), carotid stenting (CAS) according to the evidences and the judged opinions were included. Symptomatic carotid stenosis in elective and emergency, asymptomatic carotid stenosis, association with ischemic heart disease, preoperative diagnostics, types of anesthesia, monitoring in case of CEA, CEA techniques, comparison between CEA and CAS, post-surgical carotid restenosis, and medical therapy are the main topics, even with analysis of uncertainty areas for risk-benefit assessments in the individual patient (personalized medicine [PM]). Conclusions: This GL updates on the main recommendations for the most appropriate diagnostic and medical-surgical management of patients with atherosclerotic carotid artery stenosis to prevent ischemic stroke. This GL also provides useful elements for the application of PM in good clinical practice

    Spinal cord stimulation in the treatment of refractory angina: systematic review and meta-analysis of randomised controlled trials

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The aim of this paper was undertake a systematic review and meta-analysis of the use of spinal cord stimulation (SCS) in the management of refractory angina.</p> <p>Methods</p> <p>We searched a number of electronic databases including Medline, Embase and Cochrane Library up to February 2008 to identify randomised controlled trials (RCTs) reporting exercise capacity, ischemic burden, functional class, quality of life, usage of anti-anginal medication, costs and adverse events including mortality. Results were reported both descriptively for each study and using random effects meta-analysis. Given the variety in outcomes reported, some outcome results were pooled as standardised mean differences (SMD) and reported in standard deviation units.</p> <p>Results</p> <p>Seven RCTs were identified in a total of 270 refractory angina patients. The outcomes of SCS were found to be similar when directly compared to coronary artery bypass grafting (CABG) and percutaneous myocardial laser revascularisation (PMR). Compared to a 'no stimulation' control, there was some evidence of improvement in all outcomes following SCS implantation with significant gains observed in pooled exercise capacity (SMD: 0.76, 0.07 to 1.46, <it>p </it>= 0.03) and health-related quality of life (SMD: 0.83, 95% CI: 0.32 to 1.34, <it>p </it>= 0.001). Trials were small and were judged to range considerably in their quality. The healthcare costs of SCS appeared to be lower than CABG at 2-years follow up.</p> <p>Conclusion</p> <p>SCS appears to be an effective and safe treatment option in the management of refractory angina patients and of similar efficacy and safety to PMR, a potential alternative treatment. Further high quality RCT and cost effectiveness evidence is needed before SCS can be accepted as a routine treatment for refractory angina.</p

    Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

    Full text link
    Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

    Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

    Get PDF
    A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

    Mitochondrial physiology

    Get PDF
    As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

    Mitochondrial physiology

    Get PDF
    As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery
    corecore