827 research outputs found
Sealing efficacy of system B versus Thermafil and Guttacore obturation techniques evidenced by scintigraphic analysis
This study compared root canal sealing ability, filled by Continuous Wave compaction and two carrier-based obturation systems, using the nuclear medicine approach.
Fifty-five single-rooted extracted teeth were selected. The crowns were sectioned and each tooth was instrumented using rotary Protaper® Universal system. The roots were divided into 3 experimental groups and two control groups. Forty-five root canals were filled, using Continuous Wave, GuttaCore or Thermafil system and TopSeal sealer. Ten teeth were used as control. On the 7th days the apices were submersed in a solution of sodium pertechnetate 99mTc for 3 hours and the radioactivity was counted.
Although apical leakage in the Continuous Wave group was lower compared with GuttaCore and Thermafil groups, there was no statistical difference (p>0.05).
System B, GuttaCore and Thermafil techniques showed a similar sealing effect
Tools for deep-sea navigation
The SIDENAV and DEEPFLOAT innitiatives aims to develop a demonstrator that validates and apply technology that enables golds between the exploitation of mineral resources in deep-sea waters under Portuguese jurisdiction (for example the Mid-Atlantic Ridge). The Portuguese Sea is characterized by a high depth, and many natural resources are at depths greater. This makes it difficult or even hinders its exploitation through either autonomous or even through tele-operated systems use. Sustainable industrial exploitation of these marine resources require the ability to have deep sea to surface transport systems with high accuracy navigation capabilities at sustainable costs. Underwater operations are carried out by dedicated systems and for the most part with the use of ROVs (remotely operated vehicles) and AUV’s (autonomous underwater vehicles) operated from a ship or a land base station. These systems are used in a wide variety of tasks, such as, installation of equipment and maintenance in the offshore industry O&G (Oil and Gas), in the inspection of pipelines, underwater data lines, underwater observatories, power generation systems, underwater mining, as well as, the collection of information for a wide range of activities with great economic value. The movement in the water column, descent and ascent, are typically performed by buoyancy control or by conventional underwater thrusters (electric motors with propellers) using the localized movements/behaviours (such as hovering and faster manoeuvres) when necessary. The payload capacity requirements and task performance without the need for outside intervention, low power consumption and the high depth are very demanding. Based on the problem presented in the preceding paragraphs, the primary goal of the project is to develop hybrid variable ballast systems. In order to extend the range of possible operations to be held in high external pressure environments, reducing energy consumption by maximizing payload capacity and fine control in confined environments such as mining in mines with high groundwater levels (typically submerged operation). This type of system can be used in various types of underwater vehicles (AUV’s, Landers or ROV’s) or for the transport of materials or tools in the open sea or other freshwater environments. The proposed concept in this project consists of a flexible variable ballast system for deep underwater applications with advanced control capabilities. This system consists of a component that allows varying the buoyancy of a wide range of vehicles and systems for operation in the ocean environment, at different depths up to 1000m. Allows variation of buoyancy, for vehicles buoyancy trimming systems, or to change of direction of the vehicle with changes in buoyancy, and, more significantly to perform the ascend/descent motion control in the water column in an efficiently manner
Mitochondrial Fatty Acid β-Oxidation Disorders: From Disease to Lipidomic Studies—A Critical Review
ReviewThis article belongs to the Special Issue Lipid Metabolism in Pathology and Health.Fatty acid oxidation disorders (FAODs) are inborn errors of metabolism (IEMs) caused by defects in the fatty acid (FA) mitochondrial β-oxidation. The most common FAODs are characterized by the accumulation of medium-chain FAs and long-chain (3-hydroxy) FAs (and their carnitine derivatives), respectively. These deregulations are associated with lipotoxicity which affects several organs and potentially leads to life-threatening complications and comorbidities. Changes in the lipidome have been associated with several diseases, including some IEMs. In FAODs, the alteration of acylcarnitines (CARs) and FA profiles have been reported in patients and animal models, but changes in polar and neutral lipid profile are still scarcely studied. In this review, we present the main findings on FA and CAR profile changes associated with FAOD pathogenesis, their correlation with oxidative damage, and the consequent disturbance of mitochondrial homeostasis. Moreover, alterations in polar and neutral lipid classes and lipid species identified so far and their possible role in FAODs are discussed. We highlight the need of mass-spectrometry-based lipidomic studies to understand (epi)lipidome remodelling in FAODs, thus allowing to elucidate the pathophysiology and the identification of possible biomarkers for disease prognosis and an evaluation of therapeutic efficacy.This research was funded by FCT/MEC (PIDDAC) for their financial support to LAQVREQUIMTE (UIDB/50006/2020), CESAM (UIDP/50017/2020 + UIDB/50017/2020 + LA/P/0094/2020),
and the RNEM-Portuguese Mass Spectrometry Network (LISBOA-01-0145-FEDER-402-022125), financed
by FCT/MCTES through national funds and, where applicable, co-financed by the FEDER, within
the PT2020 Partnership Agreement and Compete 2020. Ana Moreira thanks the research contract
under the research unit LAQV-REQUIMTE. Inês M. S. Guerra (2021.04754.BD) and Helena B. Ferreira
(2020.04611.BD) are grateful to FCT for the PhD grants. Tânia Melo thanks the Junior Researcher contract
in the scope of the Individual Call to Scientific Employment Stimulus 2020 (CEECIND/01578/2020). The
authors are thankful to the COST Action EpiLipidNET, CA19105-Pan-European Network in Lipidomics,
and EpiLipidomics.info:eu-repo/semantics/publishedVersio
Direito ambiental: contencioso e consultivo à luz da advocacia pública
- Divulgação dos SUMÁRIOS das obras recentemente incorporadas ao acervo da Biblioteca Ministro Oscar Saraiva do STJ. Em respeito à Lei de Direitos Autorais, não disponibilizamos a obra na íntegra.- Localização na estante: 347.921.8:504(81)(094.7) D598
A Pilot for Proactive Maintenance in Industry 4.0
13th IEEE International Workshop on Factory Communication Systems (WFCS 2017). 31, May to 2, Jun, 2017. Trondheim, Norway.The reliability and safety of industrial machines
depends on their timely maintenance. The integration of Cyber
Physical Systems within the maintenance process enables both
continuous machine monitoring and the application of advanced
techniques for predictive and proactive machine maintenance.
The building blocks for this revolution – embedded sensors,
efficient preprocessing capabilities, ubiquitous connection to the
internet, cloud-based analysis of the data, prediction algorithms,
and advanced visualization methods – are already in place, but
several hurdles have to be overcome to enable their application in
real scenarios, namely: the integration with existing machines and
existing maintenance processes. Current research and
development efforts are building pilots and prototypes to
demonstrate the feasibility and the merits of advanced
maintenance techniques, and this paper describes a system for the
industrial maintenance of sheet metal working machineryinfo:eu-repo/semantics/publishedVersio
Mitochondrial fatty acid β-oxidation disorders: from disease to lipidomic studies—a critical review
Fatty acid oxidation disorders (FAODs) are inborn errors of metabolism (IEMs) caused by defects in the fatty acid (FA) mitochondrial β-oxidation. The most common FAODs are characterized by the accumulation of medium-chain FAs and long-chain (3-hydroxy) FAs (and their carnitine derivatives), respectively. These deregulations are associated with lipotoxicity which affects several organs and potentially leads to life-threatening complications and comorbidities. Changes in the lipidome have been associated with several diseases, including some IEMs. In FAODs, the alteration of acylcarnitines (CARs) and FA profiles have been reported in patients and animal models, but changes in polar and neutral lipid profile are still scarcely studied. In this review, we present the main findings on FA and CAR profile changes associated with FAOD pathogenesis, their correlation with oxidative damage, and the consequent disturbance of mitochondrial homeostasis. Moreover, alterations in polar and neutral lipid classes and lipid species identified so far and their possible role in FAODs are discussed. We highlight the need of mass-spectrometry-based lipidomic studies to understand (epi)lipidome remodelling in FAODs, thus allowing to elucidate the pathophysiology and the identification of possible biomarkers for disease prognosis and an evaluation of therapeutic efficacyinfo:eu-repo/semantics/publishedVersio
Not all farms are created equal: Shady African cocoa farms promote a richer bat fauna
Bats provide important pest suppression services with economic value to cocoa farmers, yet the impact of cocoa farm management on bat diversity metrics is still poorly understood. This is especially important if we consider that Afrotropical cocoa farms supply 68 % of the world's chocolate market, with expected increases in production in the forthcoming decades. In this study, we investigated for the first time how bat abundance, richness and diversity varied between African cocoa farms with different levels of shade tree cover, shade tree communities and cocoa characteristics. We found that shade tree cover and shade tree height were the main drivers associated with an increase of Shannon diversity, and abundance and richness of insectivores. Frugivorous and nectarivorous bats were positively associated with the presence of planted shade trees, but richness varied with the size of shade trees. The insectivorous Hipposideros fuliginosus was only present in high shade farms, being captured 51 times only in this shade system, while the frugivorous Myonycteris angolensis was associated with low shade farms. Our findings show that indeed not all farms are created equal, with high shade farms with large, tall forest shade trees (i.e., containing key plant resources) having richer bat communities. Therefore, policymakers seeking to conserve wildlife within cocoa farming systems should adopt cocoa management systems like those mentioned above and promote a combination of forest and planted shade trees to be able support a rich community of insectivorous, frugivorous and nectarivorous bats and maintain their associated ecosystems services
MEDICAMENTOS COM PROPRIEDADES ANTI-INFLAMATÓRIAS EFICAZES CONTRA A COVID-19:: UMA REVISÃO SISTEMÁTICA
A COVID-19, sigla em inglês para “coronavirusdisease 2019” (doença por coronavírus 2019), tornou-se um desafio de saúde pública na atualidade por afetar um grande número de indivíduos e, consequentemente, impactar na economia e nos sistemas de saúde de todo o mundo. Apesar desta doença ainda não contar com um tratamento específico e eficaz, estudos não clínicos e clínicos demonstram o potencial terapêutico de alguns medicamentos que têm atividade direcionada para o combate do quadro inflamatório causado pela infecção. Nesse sentido, esta revisão sistemática objetivou analisar a eficácia dos medicamentos com efeitos anti-inflamatórios contra a COVID-19, enfatizando os seus mecanismos através de testes in vivo e in vitro. A revisão da literatura foi realizada nas plataformas PubMed e ScienceDirect, no período de dezembro de 2019 a agosto de 2020, selecionando 11 artigos elegíveis ao objetivo do presente trabalho. Com isso, através de estudos preliminares dos medicamentos, obtiveram-se, em geral, resultados positivos no combate a inflamação pela COVID-19. Entretanto, destaca-se a necessidade de mais estudos para caracterizar melhor seus possíveis efeitos adversos, bem como a eficácia desses medicamentos em longo prazo
PRIMEIRO ANO DO MÓDULO DE ANEURISMA DA AORTA ABDOMINAL DO REGISTO NACIONAL DE PROCEDIMENTOS VASCULARES – IMPLEMENTAÇÃO, RESULTADOS E ORIENTAÇÕES FUTURAS
Introdução: Os registos clínicos são ferramentas fundamentais para a conhecer a realidade e poder auditar o tratamento de aneurismas da aorta abdominal (AAA). A Sociedade Portuguesa de Angiologia e Cirurgia Vascular, promotora do Registo Nacional de Procedimentos Vasculares (RNPV), desenvolveu um módulo para esta patologia que iniciou o seu funcionamento em Dezembro de 2019. O objetivo deste artigo é apresentar dados referentes ao primeiro ano de funcionamento do módulo de AAA.
Métodos: O módulo de AAA do RNPV abriu a possibilidade (voluntária) de registo em Dezembro de 2019. Após formação específica aos investigadores, os centros participantes deram início aos registos, de forma progressiva, ao longo do ano de 2020. O registo é realizado numa ferramenta informática especialmente desenvolvida para o efeito. São registados todos os casos de AAA (incluindo justa- ou supra-renais), com ou sem envolvimento das artérias ilíacas, de etiologia degenerativa. São excluídos aneurismas toraco-abdominais e ilíacos isolados. São registados dados demográficos, anatómicos, co-morbilidades, modo de admissão, detalhes sobre o tratamento e seguimento até aos 30-dias/intra- -hospitalar. O seguimento aos 1 ano e 5 anos é opcional. Para a finalidade deste relatório, foram apenas analisados dados referentes ao modo de admissão e tipo de tratamento, assim como a mortalidade aos 30-dias/intra-hospitalar.
Resultados: Entre Dezembro de 2019 e Dezembro de 2020, foram registados 350 doentes na plataforma do módulo de AAA do RNPV. A idade média dos doentes registados é de 74.3 ± 13.7 anos, e 92.0% são do sexo masculino. O modo de admissão foi eletivo em 76,9% dos casos. O diâmetro máximo do aneurisma aórtico foi em média 63.9mm ± 19.9mm. A maioria dos doentes apresentava AAA infra-renal, numa percentagem semelhante em casos eletivos e em urgência (79% vs 76%), p=0.16. A indicação para tratamento foi o diâmetro aórtico em 59.4% dos casos. O tratamento endovascular (EVAR) foi utilizado em 68.9% dos casos. Em cirurgia eletiva, a percentagem de EVAR foi 75.7% e em urgência 45.7%, p < 0.01. Em cirurgia eletiva, a mortalidade aos 30 dias ou intra-hospitalar foi de 3.3% (8 doentes). Para doentes tratados por EVAR foi de 2.8% e para cirurgia aberta 5.2%, p<0.01. A mortalidade aos 30 dias ou intra-hospitalar em urgência foi 41.9%, por EVAR foi 20.0% e por cirurgia aberta 61.6%, p<0.01.
Conclusão: No primeiro ano de funcionamento, o módulo AAA do RNPV produziu importantes dados que ajudam a compreender os padrões de tratamento desta patologia em Portugal. Estes dados podem ajudar os diferentes Serviços a melhorar a sua prática, através da comparação com os valores de referência gerados
Laboratórios virtuais: Um estudo comparativo entre plataformas de aprendizagem para o ensino da química
Como proposta para o presente estudo, analisamos os contributos e as limitações dos laboratórios virtuais para o ensino da química, com base em um estudo comparativo. O trabalho qualitativo e empírico descritivo foi desenvolvido no Departamento de Estatística e Informática da Universidade Federal Rural de Pernambuco, e foi desenvolvido no período de maio de 2016 a maio de 2017.
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