15,266 research outputs found

    Technology advancement of the electrochemical CO2 concentrating process

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    Two multicell, liquid-cooled, advanced electrochemical depolarized carbon dioxide concentrator modules were fabricated. The cells utilized advanced, lightweight, plated anode current collectors, internal liquid cooling and lightweight cell frames. Both were designed to meet the carbon dioxide removal requirements of one-person, i.e., 1.0 kg/d (2.2 lb/d)

    Technology advancement of the electrochemical CO2 concentrating process

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    The overall objectives of the present program are to: (1) improve the performance of the electrochemical CO2 removal technique by increasing CO2 removal efficiencies at pCO2 levels below 400 Pa, increasing cell power output and broadening the tolerance of electrochemical cells for operation over wide ranges of cabin relative humidity; (2) design, fabricate, and assemble development hardware to continue the evolution of the electrochemical concentrating technique from the existing level to an advanced level able to efficiently meet the CO2 removal needs of a spacecraft air revitalization system (ARS); (3) develop and incorporate into the EDC the components and concepts that allow for the efficient integration of the electrochemical technique with other subsystems to form a spacecraft ARS; (4) combine ARS functions to enable the elimination of subsystem components and interfaces; and (5) demonstrate the integration concepts through actual operation of a functionally integrated ARS

    One-man electrochemical air revitalization system evaluation

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    A program to evaluate the performance of a one man capacity, self contained electrochemical air revitalization system was successfully completed. The technology readiness of this concept was demonstrated by characterizing the performance of this one man system over wide ranges in cabin atmospheric conditions. The electrochemical air revitalization system consists of a water vapor electrolysis module to generate oxygen from water vapor in the cabin air, and an electrochemical depolarized carbon dioxide concentrator module to remove carbon dioxide from the cabin air. A control/monitor instrumentation package that uses the electrochemical depolarized concentrator module power generated to partially offset the water vapor electrolysis module power requirements and various structural fluid routing components are also part of the system. The system was designed to meet the one man metabolic oxygen generation and carbon dioxide removal requirements, thereby controlling cabin partial pressure of oxygen at 22 kN/sq m and cabin pressure of carbon dioxide at 400 N/sq m over a wide range in cabin air relative humidity conditions

    Technology advancement of the electrochemical CO2 concentrating process

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    A five-cell, liquid-cooled advanced electrochemical depolarized carbon dioxide concentrator module was fabricated. The cells utilized the advanced, lightweight, plated anode current collector concept and internal liquid-cooling. The five cell module was designed to meet the carbon dioxide removal requirements of one man and was assembled using plexiglass endplates. This one-man module was tested as part of an integrated oxygen generation and recovery subsystem

    Cell cycle-dependent phosphorylation of Theileria annulata schizont surface proteins

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    The invasion of Theileria sporozoites into bovine leukocytes is rapidly followed by the destruction of the surrounding host cell membrane, allowing the parasite to establish its niche within the host cell cytoplasm. Theileria infection induces host cell transformation, characterised by increased host cell proliferation and invasiveness, and the activation of anti-apoptotic genes. This process is strictly dependent on the presence of a viable parasite. Several host cell kinases, including PI3-K, JNK, CK2 and Src-family kinases, are constitutively activated in Theileria-infected cells and contribute to the transformed phenotype. Although a number of host cell molecules, including IkB kinase and polo-like kinase 1 (Plk1), are recruited to the schizont surface, very little is known about the schizont molecules involved in host-parasite interactions. In this study we used immunofluorescence to detect phosphorylated threonine (p-Thr), serine (p-Ser) and threonine-proline (p-Thr-Pro) epitopes on the schizont during host cell cycle progression, revealing extensive schizont phosphorylation during host cell interphase. Furthermore, we established a quick protocol to isolate schizonts from infected macrophages following synchronisation in S-phase or mitosis, and used mass spectrometry to detect phosphorylated schizont proteins. In total, 65 phosphorylated Theileria proteins were detected, 15 of which are potentially secreted or expressed on the surface of the schizont and thus may be targets for host cell kinases. In particular, we describe the cell cycle-dependent phosphorylation of two T. annulata surface proteins, TaSP and p104, both of which are highly phosphorylated during host cell S-phase. TaSP and p104 are involved in mediating interactions between the parasite and the host cell cytoskeleton, which is crucial for the persistence of the parasite within the dividing host cell and the maintenance of the transformed state

    Making intelligent systems team players: Case studies and design issues. Volume 1: Human-computer interaction design

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    Initial results are reported from a multi-year, interdisciplinary effort to provide guidance and assistance for designers of intelligent systems and their user interfaces. The objective is to achieve more effective human-computer interaction (HCI) for systems with real time fault management capabilities. Intelligent fault management systems within the NASA were evaluated for insight into the design of systems with complex HCI. Preliminary results include: (1) a description of real time fault management in aerospace domains; (2) recommendations and examples for improving intelligent systems design and user interface design; (3) identification of issues requiring further research; and (4) recommendations for a development methodology integrating HCI design into intelligent system design

    Actitudes y conductas públicas ante la COVID-19 en Estados Unidos: estudio de un caso en orden a la comprensión de un sistema político polarizado

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    How do citizens in a polarized political system react to an unexpected emergency like the COVID-19 pandemic and how do citizens process conflicting polarized narratives to formulate a public policy view of the threat of the pandemic? The emergence of the COVID-19 pandemic is a health emergency unlike anything in the United States since the polio epidemic 70 years ago, but the political climate of the U.S. in the 1950’s was far more centrist and consensual than the deep divisions observed today. This paper will utilize data from a 35-year longitudinal study of Generation X young adults (now in their mid-40’s) and a three-decade time series of national U.S. surveys to examine information acquisition behaviors to understand the new threat. Our analysis of the last 35 years of Generation X finds that polarized ideological partisanship was the strongest single predictor of individual votes in the 2020 election, but that individuals with a higher level of understanding of the coronavirus were more critical of the Trump Administration’s handling of the COVID-19 pandemic and were more likely to vote for Biden than Trump. A parallel analysis of a national probability sample of U.S. adults in 2020 found the same pattern of influence from ideological partisanship, coronavirus understanding, and assessment of the Trump Administration’s handling of the pandemic. The results indicate that knowledge and understanding can provide a critical balancing effect in an evenly divided polarized political system.¿Cómo reacciona la ciudadanía en un sistema político polarizado ante una emergencia como la pandemia de la COVID-19?, ¿cómo procesa la ciudadanía las narrativas polarizadas que están en conflicto?, y ¿qué imagen se forman de la gestión política de la amenaza de la pandemia? En EE. UU, hay que retrotraerse a la epidemia de la polio de hace 70 años para encontrar una emergencia sanitaria como la pandemia de la COVID-19. No obstante, hay importantes diferencias; en la década de 1950, el clima político de los EE.UU. era mucho más uniforme y consensuado que el actual, profundamente dividido y polarizado. Este trabajo utiliza datos de un estudio longitudinal realizado durante 35 años en personas jóvenes de la Generación X (ahora ya en la cuarentena) y datos provenientes de encuestas realizadas en Estados Unidos durante tres décadas, con el propósito de examinar los patrones de adquisición de la información en la comprensión de una nueva amenaza. Nuestro análisis de los últimos 35 años de la Generación X muestra que, en las elecciones de 2020, el factor predictivo del voto individual que tuvo más fuerza fue una ideología política polarizada, pero, aquellas personas que contaban con una mejor comprensión del coronavirus fueron más críticas con la gestión de la pandemia de la COVID-19 que realizó la administración de Donald Trump y estuvieron más predispuestas a votar por Joe Biden que a votar por Trump. Un análisis paralelo de una muestra probabilística representativa de personas adultas estadounidenses en 2020 reveló el mismo patrón de influencia del partidismo ideológico, la comprensión del coronavirus y la evaluación de la administración de Trump. Los resultados muestran que el conocimiento y la comprensión pueden proporcionar un efecto moderador crítico en un sistema político polarizado y dividido
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