Estudo de Modelos de Turbulência Aplicados à Ventilação de Espaços Interiores

Computational Fluid Dynamics has been implemented for indoor environments ventila‐ tion studies. Despite of its maturity and usefulness, its use for engineering applications such as heating, ventilation, and air conditioning (HVAC) projects is still scarce in Por‐ tugal. With this aim, this dissertation presents some introductory studies to create a computational fluid dynamics (CFD) workflow for the use by HVAC engineers with min‐ imal knowledge of CFD practices. Thus, some aspects were investigated, such as mesh design, discretization schemes, solvers, boundary conditions and turbulence models. For the latter, from a large set of turbulence models, six Reynolds‐averaged Navier‐Stokes (RaNS) turbulence models were tested and validated for indoor ventilation, the standard k − ε, the renormalization group (RNG) k − ε, the realizable k − ε, the v ′2 − f, the k − ω and the k−ω shear stress transport (SST). The standard k−ε model continues to present the most satisfactory results of all the studied turbulence models. The RNG k − ε model also showed good agreement with the experimental data, however it required more time to achieve convergence. It was not possible to achieve convergence with the realizable k −ε model. The k −ω and k −ω SST models yield results significantly different from the experimental measurements, especially in the far wall region. These studies were com‐ pared with the benchmarks from the International Energy Agency Annex 20. This work also presents 2D and 3D cases, mesh convergence studies, effects of flow buoyancy (incompressible, isothermal and non‐isothermal cases), and steady‐state and tran‐sient flow simulations.Mecânica dos Fluídos Computacional tem sido implementada em estudos de ventilação de espaços interiores. Apesar da sua maturidade e utilidade, a sua utilização para apli‐ cações de engenharia como projetos de aquecimento, ventilação e ar condicionado (AVAC) ainda é escassa em Portugal. Com este objetivo, esta dissertação apresenta alguns estudos introdutórios para a criação de um workflow de mecânica de fluídos computacional (CFD) para uso por engenheiros de AVAC com pouco conhecimento acerca de práticas de CFD. Assim, alguns aspetos foram investigados, tais como, geração de malhas, esquemas de discretização, solvers, condições de fronteira e modelos de turbulência. A partir de uma panóplia de modelos de turbulência, seis modelos de Reynolds‐averaged Navier‐Stokes (RaNS) de turbulência foram testados e validados para espaços interiores, standard k − ε, renormalization group (RNG) k − ε, realizable k − ε, v ′2 − f, k − ω e k−ω shear stress transport. O modelo standard k−ε apresenta os resultados mais satis‐ fatórios entre os estudados. O modelo RNG k−ε também demonstrou boa concordância com os resultados experimentais disponíveis na literatura, no entanto necessita de mais tempo de simulação para convergir do que o modelo standard k − ε. Com o realizable k − ε não foi possível obter convergência e os modelos k − ω e k − ω SST produzem resultados significativamente desfasados da realidade, especialmente na zona afastada das paredes. Estes estudos foram comparados com benchmarks do International Energy Agency Annex 20. Esta dissertação também apresenta estudos de convergência de malhas, efeitos de im‐ pulsão sobre o escoamento (casos incompressíveis, isotérmicos e não isotérmicos) e sim‐ ulações de escoamento em regime permanente e transiente

Small electron transfer proteins as mediators in enzymatic electrochemical biosensors

The final publication is available at Springer."Electrochemical mediators transfer redox equivalents between the active sites of enzymes and electrodes and, in this way, trigger bioelectrocatalytic redox processes. This has been very useful in the development of the so-called second generation biosensors, where they are able to transduce the catalytic event into an electrical signal. Among other pre-requisites, redox mediators must be readily oxidized/reduced at the electrode surface and easily interact with the biorecognition component. Small chemical compounds (e.g. ferrocene derivatives, ruthenium or osmium complexes and viologens) are frequently used for this purpose, but lately, small redox proteins (e.g. horse heart cytochrome c) have also played the role of redox partners in biosensing applications. In general, the docking between two complementary proteins introduces a second level of selectivity to the biosensor and enlarges the list of compounds targeted for analysis. Moreover, electrochemical interferences are frequently minimized owing to the small overpotentials achieved. This paper aims to provide an overview of enzyme biosensors that are mediated by electron transfer proteins. The article begins with a few considerations on mediated electrochemistry in biosensing 2 systems and proceeds with a detailed description of relevant works concerning the cooperative use of redox enzymes and biological electron donors/acceptors.

Nuclear-Mitochondrial Intergenomic Communication Disorders

The focus of this chapter is to review the clinical and molecular etiologies of nuclear defects involved in mtDNA stability and in mitochondrial protein synthesis. The overview done here will hopefully provide insights towards best diagnostic strategies of mitochondrial cross–talk disorders, being useful for clinicians when facing similar cases. Additionally we will present a diagnostic algorithm for these diseases based on our knowledge

V&V of Lexical, Syntactic and Semantic Properties for Interactive Systems Through Model Checking of Formal Description of Dialog

International audienceDuring early phases of the development of an interactive system, future system properties are identified (through interaction with end users in the brainstorming and prototyping phase of the application, or by other stakeholders) imposing requirements on the final system. They can be specific to the application under development or generic to all applications such as usability principles. Instances of specific properties include visibility of the aircraft altitude, speed… in the cockpit and the continuous possibility of disengaging the autopilot in whatever state the aircraft is. Instances of generic properties include availability of undo (for undoable functions) and availability of a progression bar for functions lasting more than four seconds. While behavioral models of interactive systems using formal description techniques provide complete and unambiguous descriptions of states and state changes, it does not provide explicit representation of the absence or presence of properties. Assessing that the system that has been built is the right system remains a challenge usually met through extensive use and acceptance tests. By the explicit representation of properties and the availability of tools to support checking these properties, it becomes possible to provide developers with means for systematic exploration of the behavioral models and assessment of the presence or absence of these properties. This paper proposes the synergistic use two tools for checking both generic and specific properties of interactive applications: Petshop and Java PathFinder. Petshop is dedicated to the description of interactive system behavior. Java PathFinder is dedicated to the runtime verification of Java applications and as an extension dedicated to User Interfaces. This approach is exemplified on a safety critical application in the area of interactive cockpits for large civil aircrafts

The numerical analysis of higher-order nonlinear FE method for advection dominated problems

The numerical analysis of nonlinear discontinuity-capturing methods applied to advection dominated problems has not been completely established yet. Some particular results give very good contribution towards the existence of discrete solutions although no uniqueness results are demonstrated. This paper studies the conditions for the uniqueness of the solution when using to the CAU (Consistent Approximate Upwind) Petrov-Galerkin for solving advection dominated problems. The main issue in this analysis is that it relies on the optimality property of the CAU solution which does not depend on any restrictions of the approximation spaces

A comprehensive view of nitrite reductases

The authors acknowledge the support of the research centers Applied Molecular Biosciences Unit-UCIBIO, which is co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007728). CMS acknowledges support from Project LISBOA-01-0145-FEDER-007660 (Microbiologia Molecular, Estrutural e Celular) funded by FEDER funds through COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI). Publisher Copyright: © 2022 Elsevier B.V.The last years have witnessed a steady increase of social and political awareness for the need of studying, monitoring, and controlling several anthropological activities that are dramatically impacting the environment and human health. The increasing turnover rates of the nitrogen cycle across the Planet are of major concern, so the understanding of the biological, chemical, and physical processes associated with the biogeochemical nitrogen cycle has been attracting the attention of several scientific disciplines. For many years, the primary focus has been the so-called “dissimilatory reduction of nitrate”, which refers to the stepwise conversion of nitrate into molecular nitrogen, closely followed by the assimilatory nitrate reduction pathway, which allow nitrogen incorporation into biomolecules. The contribution of bioinorganic chemists to better understand the enzymology underlying these two branches of the N-cycle has been remarkable. The constant development of mechanistic, structural, and biological tools has been keeping this bioinorganic chemistry field very active, making it a highly relevant research area still today. In this paper, we review the state-of-the-art in both dissimilatory and assimilatory nitrite reducing enzymes, highlighting the structural peculiarities of the different metalloenzymes involved in this step.publishersversionpublishe

Health Literacy in Younger Age Groups: Health Care Perceptions: Informed People Will Be More Prepared People

Background: Young people and adolescents are increasingly using digital platforms for various purposes, including health aspects, which is not linear about whether they consider health information important or understand it. Objectives: Exploratory study with 51 individuals aged 17 to 25 years to ascertain their perception of health issues. Methodology: For this study, a 10-question questionnaire survey was elaborated and distributed online via the Facebook Social Network to 51 male and female adolescents, aged 17 to 25, living in the Greater Lisbon area, college students. Conclusions and Relevance: Young people want to know about their health, but feel that they should do this research by themselves. On the other hand, health information research and using skills demonstrate a failure in both access to reliable information and processing and understanding.info:eu-repo/semantics/publishedVersio

Identification of candida clinical isolates by PCR fingerprinting : a contribution to the study of molecular epidemiology of candidiasis in portugal

PCR fingerprinting with a single non-specific primer (T3B) was used to type yeast clinical isolates obtained from two Medical Institutions in north Portugal. Of the 177 strains isolated, 112 were obtained from vaginal swabs, 24 from urine, 23 from the upper respiratory system, seven from the anal mucosa and 11 were isolated from various sources including blood, pus, catheter and peritoneal fluid. All the isolates belonged to the genus Candida being the profiles obtained highly similar within a species and clearly distinct among species. Seven different species were identified: C. albicans, C. tropicalis, C. glabrata, C. guilliermondii, C. parapsilosis, C. krusei and C.lusitaniae. This methodology also allowed the distinction of C. dubliniensis which is very closely related to C. albicans. Cluster analysis of the global fingerprints obtained originated, in general, groups corresponding to each species analysed except for five strains which were submitted to 26S and ITS rDNA sequencing to confirm their identity. We demonstrate that although C. albicans is the predominant species found, other Candida species were present accounting for over 20% of the strains isolated. The most common non albicans species were C. tropicalis, C. glabrata and C. parapsilosis. Due to its predominance over the other species C. albicans was present in all types of clinical material except in blood samples. C. tropicalis was mainly recovered from the urine and respiratory tract. This study represents the first large-scale approach to the knowledge of Candida species present in hospital settings in Portugal.Fundação para a Ciência e Tecnologia (FCT) Ciências do Ambiente da Universidade do Minho (CCA

Alfredina de Paiva e Souza e o Instituto de Educação do Rio de Janeiro: a vanguarda da tabuada na era dos testes.

Disponível em: http://aplicacoes.ifs.edu.br/periodicos/index.php/caminhos_da_educacao_matematica/article/view/5/4O artigo apresenta a pesquisa desenvolvida por Alfredina de Paiva e Souza, professora chefe da seção de Prática de Ensino do curso de formação do professor primário do Instituto de Educação do Rio de Janeiro, na década de 1930, período marcado pelo movimento da Escola Nova. No presente estudo analisamos, pelo ferramental teórico metodológico da História Cultural, manuais de ensino e artigos intentando compreender as representações e apropriações de Alfredina de Paiva e Souza, que por meio de pesquisa experimental e inédita, realizou testes em escolas públicas do Rio de Janeiro para saber quais combinações das tabuadas os alunos apresentavam maior dificuldade. Alfredina reafirmou a necessidade de decorar a tabuada, mas diferentemente do método “tradicional”, em que a tabuada era decorada pela ordem crescente dos números, indicou o estudo das tabuadas por combinações divididas em ordem de dificuldade. Também referenciou a necessidade de exatidão nos resultados e organizou testes de velocidade. A proposta desenvolvida por Alfredina foi fruto de pesquisas baseadas em testes e conhecimentos científicos internacionais, desenvolvidos por psicólogos, como o caso de Edward Lee Thorndike e Frank Leslie Clapp. Período em que os testes ganham importância como ferramentas de apoio para legitimar a Pedagogia como um conhecimento científico. As medidas estatísticas e a Psicologia determinam uma nova forma de compreender a criança, e consequentemente configuram novas formas de ensinar da tabuada