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The Radiation and Dust Sensor is one of six sensors of the Mars Environmental Dynamics Analyzer onboard the Perseverance rover from the Mars 2020 NASA mission. Its primary goal is to characterize the airbone dust in the Mars atmosphere, inferring its concentration, shape and optical properties. Thanks to its geometry, the sensor will be capable of studying dust-lifting processes with a high temporal resolution and high spatial coverage. Thanks to its multiwavelength design, it will characterize the solar spectrum from Mars' surface. The present work describes the sensor design from the scientific and technical requirements, the qualification processes to demonstrate its endurance on Mars' surface, the calibration activities to demonstrate its performance, and its validation campaign in a representative Mars analog. As a result of this process, we obtained a very compact sensor, fully digital, with a mass below 1 kg and exceptional power consumption and data budget features.
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Poeira , Meio Ambiente Extraterreno , AtmosferaRESUMO
BACKGROUND: Despite the recent advances in computational fluid dynamics (CFD) techniques applied to blood flow within the left atrium (LA), the relationship between atrial geometry, flow patterns, and blood stasis within the left atrial appendage (LAA) remains unclear. A better understanding of this relationship would have important clinical implications, as thrombi originating in the LAA are a common cause of stroke in patients with atrial fibrillation (AF). AIM: To identify the most representative atrial flow patterns on a patient-specific basis and study their influence on LAA blood stasis by varying the flow split ratio and some common atrial modeling assumptions. METHODS: Three recent techniques were applied to nine patient-specific computational fluid dynamics (CFD) models of patients with AF: a kinematic atrial model to isolate the influence of wall motion because of AF, projection on a universal LAA coordinate system, and quantification of stagnant blood volume (SBV). RESULTS: We identified three different atrial flow patterns based on the position of the center of the main circulatory flow. The results also illustrate how atrial flow patterns are highly affected by the flow split ratio, increasing the SBV within the LAA. As the flow split ratio is determined by the patient's lying position, the results suggest that the most frequent position adopted while sleeping may have implications for the medium- and long-term risks of stroke.
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Apêndice Atrial , Fibrilação Atrial , Modelos Cardiovasculares , Humanos , Apêndice Atrial/fisiopatologia , Apêndice Atrial/diagnóstico por imagem , Fibrilação Atrial/fisiopatologia , Masculino , Feminino , Idoso , Átrios do Coração/fisiopatologia , Pessoa de Meia-Idade , Hidrodinâmica , Simulação por ComputadorRESUMO
BACKGROUND: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, affecting over 1% of the population. It is usually triggered by irregular electrical impulses that cause the atria to contract irregularly and ineffectively. It increases blood stasis and the risk of thrombus formation within the left atrial appendage (LAA) and aggravates adverse atrial remodeling. Despite recent efforts, LAA flow patterns representative of AF conditions and their association with LAA stasis remain poorly characterized. AIM: To develop reduced-order data-driven models of LAA flow patterns during atrial remodeling in order to uncover flow disturbances concurrent with LAA stasis that could add granularity to clinical decision criteria. METHODS: We combined a geometric data augmentation process with projection of results from 180 CFD atrial simulations on a universal LAA coordinate (ULAAC) system. The projection approach enhances data visualization and facilitates direct comparison between different anatomical and functional states. ULAAC projections were used as input for a proper orthogonal decomposition (POD) algorithm to build reduced-order models of hemodynamic metrics, extracting flow characteristics associated with AF and non-AF anatomies. RESULTS: We verified that the ULAAC system provides an adequate representation to visualize data distributions on the LAA surface and to build POD-based reduced-order models. These models revealed significant differences in LAA flow patterns for atrial geometries that underwent adverse atrial remodeling and experienced elevated blood stasis. Together with anatomical morphing-based patient-specific data augmentation, this approach could facilitate data-driven analyses to identify flow features associated with thrombosis risk due to atrial remodeling.
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BACKGROUND: COVID-19 pandemic varies greatly and has different dynamics in every country, city, and hospital in Latin America. Obesity increases the risk of SARS-CoV-2 infection, and it is one of the independent risk factors for the most severe cases of COVID-19. Currently, the most effective treatment against obesity available is bariatric and metabolic surgery (BMS), which further resolves or improves other independent risk factors like diabetes and hypertension. OBJECTIVE: Provide recommendations for the resumption of elective BMS during COVID-19 pandemic. METHOD: This document was created by the IFSO-LAC Executive Board and a task force. Based on data collected from a survey distributed to all IFSO-LAC members that obtained 540 responses, current evidence available, and consensus reached by other scientific societies. RESULTS: The resumption of elective BMS must be a priority maybe similar to oncological surgery, when hospitals reach phase I or II, treating obesity patients in a NON-COVID area, avoiding inadvertent intrahospital contagion from healthcare provider, patients, and relatives. Same BMS indication and types of procedures as before the pandemic. Discard the presence of SARS-CoV-2 within 72 h prior to surgery. Continues laparoscopic approach. The entire team use N95 mask. Minimum hospital stays. Implement remote visits for the follow-up. CONCLUSION: Resumption of elective BMS is crucial because it is not only a weight loss operation but also resolves or improves comorbidities and appears to be an immune restorative procedure of obese patients in the medium term, offering them the same probability of contracting COVID-19 as the regular population.
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Cirurgia Bariátrica , Betacoronavirus , Infecções por Coronavirus , Obesidade Mórbida/cirurgia , Pandemias , Pneumonia Viral , COVID-19 , Procedimentos Cirúrgicos Eletivos , Humanos , América Latina , Guias de Prática Clínica como Assunto , SARS-CoV-2 , Inquéritos e QuestionáriosRESUMO
Se realizó un estudio descriptivo y transversal sobre la mortalidad por accidentes en la provincia de Santiago de Cuba según variables epidemiológicas analizadas en el período 2000 2004, cuyos datos se obtuvieron de la Vicedirección Primera del Centro Provincial de Higiene, Epidemiología y Microbiología del territorio. Durante el bienio 2000 - 2001 se presentaron las mayores tasas de mortalidad (36,6 y 34,9 por 100 000 habitantes, respectivamente), con una tendencia estacionaria (más de 30 por 100 000 habitantes)en todo el quinquenio. Hubo 37 889 años de vida potencialmente perdidos por accidentes de diferentes tipos (76 por ciento sufridos por personas en la plenitud de sus capacidades productivas), para una tasa promedio de 7,6, solo superada en el 2000 (8,7) y 2002 (7,9)