Demonstration of fundamental mode only propagation in highly multimode fibre for high power EDFAs

The use of short lengths of large core phosphate glass fibre, doped with high concentrations of Er or Er:Yb represents an attractive route to achieving high power erbium doped fibre amplifiers (EDFAs) and lasers (EDFLs). With the aim of investigating the potential of achieving diffraction limited output from such large core fibres, we present experimental results of fundamental mode propagation through a 20 cm length of passive 300 micrometer core multimode fibre when the input is a well-aligned Gaussian beam. Through careful control of fibre geometry, input beam parameters and alignment, we measured an output M squared of 1.1 + - 0.05. The fibre had a numerical aperture of 0.389, implying a V number of 236.8. To our knowledge, this is the largest core fibre through which diffraction limited fundamental mode propagation has been demonstrated. Although the results presented here relate to undoped fibre, they do provide the practical basis for a new generation of EDFAs and EDFLs.Comment: 5 figure

O profissional de contabilidade de gestão em Portugal

As transformações e mudanças que ocorrem no mundo empresarial e nos negócios, têm um impacto directo no exercício da profissão de contabilidade. O desenvolvimento das organizações empresariais suscita discussão na sociedade sobre a função do profissional de contabilidade na gestão dos negócios e o seu papel no auxílio à resolução de problemas das empresas. Com estes desenvolvimentos o profissional de contabilidade de gestão passou a ter maior relevância tanto no meio académico, como no mercado, que procura profissionais especializados, com visão de gestão, planeamento fiscal, financeiro e de contabilidade. A classe profissional deve estar atenta às perspectivas e tendências, para que o profissional de contabilidade se torne cada vez mais relevante no apoio à tomada de decisões empresariais. Ele deverá ser visto como um comunicador de informação essencial para a tomada de decisão, com a sua capacidade de avaliar os factos passados, perceber os factos presentes e prever os eventos futuros. Pretende-se, assim, fazer um enquadramento histórico da profissão, alargando o âmbito ao profissional de contabilidade em geral, abordar a situação do profissional de contabilidade de gestão nos dias que correm, bem como enunciar os principais desafios que o profissional de contabilidade de gestão terá que atravessar

Concurrent and predictive validity of glim criteria to identify undernutrition in hospitalized patients

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Bioremediation of Polluted Waters Using Microorganisms

Water pollution is an issue of great concern worldwide, and it can be broadly divided into three main categories, that is, contamination by organic compounds, inorganic compounds (e.g., heavy metals), and microorganisms. In recent years, the number of research studies concerning the use of efficient processes to clean up and minimize the pollution of water bodies has been increasing. In this context, the use of bioremediation processes for the removal of toxic metals from aqueous solutions is gaining considerable attention. Bioremediation can be defined as the ability of certain biomolecules or types of biomass to bind and concentrate selected ions or other molecules present in aqueous solutions. Bioremediation using microorganisms shows great potential for future development due to its environmental compatibility and possible cost-effectiveness. A wide range of microorganisms, including bacteria, fungi, yeasts, and algae, can act as biologically active methylators, which are able to at least modify toxic species. Many microbial detoxification processes involve the efflux or exclusion of metal ions from the cell, which in some cases can result in high local concentrations of metals at the cell surface, where they can react with biogenic ligands and precipitate. Although microorganisms cannot destroy metals, they can alter their chemical properties via a surprising array of mechanisms. The main purpose of this chapter is to provide an update on the recent literature concerning the strategies available for the remediation of metal-contaminated water bodies using microorganisms and to critically discuss their main advantages and weaknesses. The focus is on the heavy metals associated with environmental contamination, for instance, lead (Pb), cadmium (Cd), and chromium (Cr), which are potentially hazardous to ecosystems. The types of microorganisms that are used in bioremediation processes due to their natural capacity to biosorb toxic heavy metal ions are discussed in detail. This chapter summarizes existing knowledge on various aspects of the fundamentals and applications of bioremediation and critically reviews the obstacles to its commercial success and future perspectives

Potential Exposure and Risk Associated with Metal Contamination in Foods

Humans require several trace elements as components of the diet. Some of these elements are required in extremely small quantities (only micrograms per day). On the other hand, in higher concentrations, some elements may also have deleterious, even lethal, effects. Metals such as arsenic, chromium (Cr), lead (Pb), and mercury (Hg) are naturally occurring chemical compounds. The contamination of food with these metals occurs mainly through human activities, such as farming and industry, or from contamination during food processing and storage. People can be exposed to these metals by ingesting contaminated food or water, and their accumulation in the body can lead to harmful effects over time. The main objective of this chapter is to provide a literature review on the various types of foodborne poisoning caused by the contamination of food with arsenic, Cr, Pb, and Hg and on food safety issues associated with the presence of these metals in food. Research findings from various studies carried out to examine the relationship between metal exposure and the adverse health effects of metals are addressed

Denervação simpática renal em pacientes com cardiodesfibrilador implantável e tempestade elétrica

ResumoIntroduçãoCardiodesfibriladores implantáveis (CDIs) são geralmente indicados para pacientes com arritmias malignas considerados de alto risco. A hiperatividade simpática desempenha um papel crítico no desenvolvimento, na manutenção e no agravamento de arritmias ventriculares. Novas opções de tratamento nessa população representam uma necessidade clínica. Nosso objetivo foi relatar os resultados de pacientes com CDIs e tempestade elétrica submetidos à denervação simpática renal para controle da arritmia.MétodosOito pacientes com CDIs internados por tempestade elétrica refratária ao tratamento médico otimizado foram submetidos à denervação simpática renal. Condições subjacentes foram: doença de Chagas (n = 6), cardiomiopatia dilatada não isquêmica (n = 1) e cardiomiopatia isquêmica (n = 1). As informações sobre o número de taquicardias ventriculares/fibrilações ventriculares e episódios de terapias antitaquicardia na última semana pré‐procedimento e nos 30 dias pós‐tratamento foram obtidas por meio de interrogação dos CDIs.ResultadosAs medianas dos episódios de taquicardias ventriculares/fibrilações ventriculares, sobre‐estimulação e choques na semana que antecedeu a denervação simpática renal foram de 29 (9 a 106), 23 (2 a 94) e 7,5 (1 a 88), sendo significativamente reduzidas para 0 (0 a 12), 0 (0 a 30) e 0 (0 a 1), respectivamente, 1 mês após o procedimento (p = 0,002; p = 0,01; p = 0,003). Nenhum paciente morreu durante o acompanhamento. Não ocorreram complicações maiores relacionadas ao procedimento.ConclusõesEm pacientes com CDIs e tempestade elétrica refratária ao tratamento médico otimizado, a denervação simpática renal reduziu significativamente a carga de arritmia e, consequentemente, as sobre‐estimulações e os choques. Ensaios clínicos randomizados, no contexto de denervação simpática renal para controle de arritmias cardíacas refratárias, são necessários para trazer maior robustez aos nossos achados.AbstractBackgroundImplantable cardioverter‐defibrillators (ICDs) are usually indicated for patients with malignant arrhythmias considered as high risk. Sympathetic hyperactivity plays a critical role in the development, maintenance, and worsening of ventricular arrhythmias. New treatment options in this population represent a clinical necessity. This study's objective was to report the outcomes of patients with ICDs and electrical storm submitted to renal sympathetic denervation for arrhythmia control.MethodsEight patients with ICDs admitted for electrical storm refractory to optimal medical therapy underwent renal sympathetic denervation. Underlying diseases included Chagas disease (n = 6), non‐ischemic dilated cardiomyopathy (n = 1), and ischemic cardiomyopathy (n = 1). Information on the number of episodes of ventricular tachycardia/ventricular fibrillation and antitachycardia therapies in the week before the procedure and 30 days after treatment were obtained through interrogation of the ICDs.ResultsThe median numbers of episodes of ventricular tachycardia/ventricular fibrillation, antitachycardia pacing, and shocks in the week before renal sympathetic denervation were 29 (9 to 106), 23 (2 to 94), and 7.5 (1 to 88), and significantly reduced to 0 (0 to 12), 0 (0 to 30), and 0 (0 to 1), respectively, 1 month after the procedure (p = 0.002; p = 0.01; p = 0.003, respectively). No patients died during follow‐up. There were no major complications related to the procedure.ConclusionsIn patients with ICDs and electrical storm refractory to optimal medical treatment, renal sympathetic denervation significantly reduced arrhythmia load and, consequently, antitachycardia pacing and shocks. Randomized clinical trials in the context of renal sympathetic denervation to control refractory cardiac arrhythmias are needed to further support these findings

Modulation of apoplast proteome by downy mildew in susceptible and tolerant grapevine cultivars

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