Boundary layer control by means of DBD plasma actuators

In this thesis a new aerodynamic model to simulate the behavior of Dielectric Barrier Discharge actuator has been studied. For this task, two different models have been merged in order to provide a more accurate one. The model has been implemented using commercial computational fluid dynamics software through builtin tools. Different configurations have been followed up in order to validate the model. During this validation, the phenomena ocurring in the different configurations has been studied, remarking on the ability of the modelled devices to have an effect on low-speed flows, with different extent. The model has the aim of improving and easing the computational side of this actuators, that tend to couple electric, fluid an kinetic phenomena; with the scope of investigating its potential in different applications in a simpler way.Ingeniería Aeroespacia

Artesãos, cartografia e império. A produção social de um instrumento náutico no mundo ibérico, 1500-1650

Explicar cómo y en qué condiciones fueron construidos algunos de los instrumentos científicos más emblemáticos del mundo moderno sigue siendo un desafío para los historiadores de la ciencia y de la tecnología. Este principio afecta también a los instrumentos náuticos. Así, el objetivo del presente artículo es considerar el “cómo” y el “en qué condiciones”, en un sentido amplio, analizando uno de estos artefactos: las cartas náuticas construidas durante la expansión marítima europea. Originalidad: La originalidad del texto no reside únicamente en llevar a cabo una reconstrucción de este instrumento en Portugal y España que aporte nuevos datos sobre su proceso de fabricación y sus fabricantes, sino también en arrojar luz sobre antiguos debates historiográficos que subyacen a la génesis de la ciencia moderna, tales como la difícil colaboración entre hombres prácticos y hombres teóricos; la aportación de comunidades de artesanos al mundo del conocimiento; el papel que los saberes prácticos tuvieron en el establecimiento de nuevas formas de estandarización en ciencia; la adopción de una metodología empírica para el dominio del mundo o la construcción de grandes imperios globales cimentados sobre la base del trabajo manual. Metodología: El análisis de estos debates requiere una aproximación metodológica que atienda a las categorías y los conceptos principales puestos en circulación tanto por la historia como por la filosofía de la ciencia más reciente. En definitiva, se trata de atender a las condiciones que permitieron el establecimiento de acuerdos (y también de controversias) epistemológicos entre diferentes comunidades de conocimiento tomando un instrumento náutico como “mediador”. Conclusiones: El artículo concluye que la consideración de las culturas empíricas del conocimiento y sus realizaciones materiales son una condición sine qua non para entender la génesis de la modernidad científica europea y la construcción de un mundo globalExplaining how and under what conditions some of the most emblematic scientific instruments of the modern world were built remains a challenge for historians of science and technology. This principle also affects nautical instruments. Thus, the objective of this article is to consider the “how” and the “under what conditions”, in a broad sense, by examining one of these devices: the nautical charts developed during the European maritime expansion. Originality: The originality of this article lies not only in the reconstruction of this instrument in Portugal and Spain, providing new information about its development process and its manufacturers, but also in shedding light on old historiographical debates that underlie the genesis of modern science, such as the difficult collaboration between practical men and theoretical men; the contribution of artisan communities to the world of knowledge; the role that practical knowledge played in the establishment of new forms of standardization in science; the adoption of an empirical methodology for achieving mastery of the world or the construction of large global empires founded upon manual labor. Methodology: Analyzing these debates requires a methodological approach that addresses the main categories and concepts put into circulation by the most recent history and philosophy of science. In short, unveiling the conditions that enabled the establishment of epistemological agreements (and also disputes) between different knowledge communities by taking a nautical instrument as “mediator.” Conclusions: The article concludes that examining empirical knowledge cultures and their material achievements are a sine qua non condition to understand the genesis of European scientific modernity and the construction of a global worldExplicar como e em que condições foram construídos alguns dos instrumentos científicos mais emblemáticos do mundo moderno continua sendo um desafio para os historiadores da ciência e da tecnologia. Esse princípio afeta também os instrumentos náuticos. Assim, o objetivo do presente artigo é considerar o “como” e o “em que condições”, em um sentido amplo, e analisar um desses artefatos: as cartas náuticas construídas durante a expansão marítima europeia. Originalidade: A originalidade do texto não reside unicamente na realização de uma reconstrução desse instrumento em Portugal e na Espanha de forma que traga novos dados sobre seu processo de fabricação e de seus fabricantes, mas também em lançar luz sobre antigos debates historiográficos que subjazem à gênese da ciência moderna, tais como a difícil colaboração entre homens práticos e homens teóricos, a contribuição de comunidades de artesãos ao mundo do conhecimento; o papel que os saberes práticos tiveram no estabelecimento de novas formas de padronização na ciência, a adoção de uma metodologia empírica para o domínio do mundo ou a construção de grandes impérios globais cimentados sobre a base do trabalho manual. Metodologia: A análise desses debates requer uma aproximação metodológica que atenda às categorias e aos principais conceitos colocados em circulação tanto pela história quanto pela filosofia da ciência mais recente. Definitivamente, trata-se de atender às condições que permitiram o estabelecimento de acordos (e também de controvérsias) epistemológicos entre diferentes comunidades de conhecimento tomando o instrumento náutico como “mediador”. Conclusões: O artigo conclui que a consideração das culturas empíricas do conhecimento e suas realizações materiais são uma condição sine qua non para entender a gênese da modernidade científica europeia e a construção de um mundo globa

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

Métodos y técnicas de monitoreo y predicción temprana en los escenarios de riesgos socionaturales

Esta obra concentra los métodos y las técnicas fundamentales para el seguimiento y monitoreo de las dinámicas de los escenarios de riesgos socionaturales (geológicos e hidrometeorológicos) y tiene como objetivo general orientar, apoyar y acompañar a los directivos y operativos de protección civil en aterrizar las acciones y políticas públicas enfocadas a la gestión del riesgo local de desastre

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

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

X chromosome inactivation does not necessarily determine the severity of the phenotype in Rett syndrome patients

Rett syndrome (RTT) is a severe neurological disorder usually caused by mutations in the MECP2 gene. Since the MECP2 gene is located on the X chromosome, X chromosome inactivation (XCI) could play a role in the wide range of phenotypic variation of RTT patients; however, classical methylation-based protocols to evaluate XCI could not determine whether the preferentially inactivated X chromosome carried the mutant or the wild-type allele. Therefore, we developed an allele-specific methylation-based assay to evaluate methylation at the loci of several recurrent MECP2 mutations. We analyzed the XCI patterns in the blood of 174 RTT patients, but we did not find a clear correlation between XCI and the clinical presentation. We also compared XCI in blood and brain cortex samples of two patients and found differences between XCI patterns in these tissues. However, RTT mainly being a neurological disease complicates the establishment of a correlation between the XCI in blood and the clinical presentation of the patients. Furthermore, we analyzed MECP2 transcript levels and found differences from the expected levels according to XCI. Many factors other than XCI could affect the RTT phenotype, which in combination could influence the clinical presentation of RTT patients to a greater extent than slight variations in the XCI pattern