156 research outputs found

    Information Presentation

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    The goal of the Information Presentation Directed Research Project (DRP) is to address design questions related to the presentation of information to the crew. The major areas of work, or subtasks, within this DRP are: 1) Displays, 2) Controls, 3) Electronic Procedures and Fault Management, and 4) Human Performance Modeling. This DRP is a collaborative effort between researchers at Johnson Space Center and Ames Research Center

    Late syn- to post-collisional magmatism in Madagascar: the genesis of the Ambalavao and Maevarano Suites

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    The East African Orogen involves a collage of Proterozoic microcontinents and arc terranes that became wedged between older cratonic blocks during the assembly of Gondwana. The Ediacaran–Cambrian Ambalavao and Maevarano Suites in Madagascar were emplaced during the waning orogenic stages and consist of weakly deformed to undeformed plutonic rocks and dykes of mainly porphyritic granite but also gabbro, diorite and charnockite. U-Pb geochronological data date emplacement of the Ambalavao Suite to between ca. 580 Ma and 540 Ma and the Maevarano Suite to between ca. 537 Ma and 522 Ma. Major and trace element concentrations are consistent with emplacement in a syn- to post-collisional tectonic setting as A-type (anorogenic) suites. Oxygen (δ¹⁸O of 5.27‰–7.45‰) and hafnium (εHf(t) of –27.8 to –12.3) isotopic data from plutons in the Itremo and Antananarivo Domains are consistent with incorporation of an ancient crustal source. More primitive δ¹⁸O (5.27‰–5.32‰) and εHf(t) (+0.0 to +0.2) isotopic values recorded in samples collected from the Ikalamavony Domain demonstrate the isotopic variation of basement sources present in the Malagasy crust. The Hf isotopic composition of Malagasy zircon are unlike more juvenile Ediacaran–Cambrian zircon sources elsewhere in the East African Orogen and, as such, Madagascar represents a distinct and identifiable detrital zircon source region in Phanerozoic sedimentary provenance studies. Taken together, these data indicate that high-T crustal anatexis, crustal assimilation and interaction of crustal material with mantle-derived melts were the processes operating during magma emplacement. This magmatism was coeval with polyphase deformation throughout Madagascar during the amalgamation of Gondwana and magmatism is interpreted to reflect lithospheric delamination of an extensive orogenic plateau.Donnelly B. Archibald, Alan S. Collins, John D. Foden, Justin L. Payne, Peter Holden, Théodore Razakamanan

    Synthesizing attractors of Hindmarsh-Rose neuronal systems

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    In this paper a periodic parameter switching scheme is applied to the Hindmarsh-Rose neuronal system to synthesize certain attractors. Results show numerically, via computer graphic simulations, that the obtained synthesized attractor belongs to the class of all admissible attractors for the Hindmarsh-Rose neuronal system and matches the averaged attractor obtained with the control parameter replaced with the averaged switched parameter values. This feature allows us to imagine that living beings are able to maintain vital behavior while the control parameter switches so that their dynamical behavior is suitable for the given environment.Comment: published in Nonlinear Dynamic

    The long-term fate of permafrost peatlands under rapid climate warming

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    Permafrost peatlands contain globally important amounts of soil organic carbon, owing to cold conditions which suppress anaerobic decomposition. However, climate warming and permafrost thaw threaten the stability of this carbon store. The ultimate fate of permafrost peatlands and their carbon stores is unclear because of complex feedbacks between peat accumulation, hydrology and vegetation. Field monitoring campaigns only span the last few decades and therefore provide an incomplete picture of permafrost peatland response to recent rapid warming. Here we use a high-resolution palaeoecological approach to understand the longer-term response of peatlands in contrasting states of permafrost degradation to recent rapid warming. At all sites we identify a drying trend until the late-twentieth century; however, two sites subsequently experienced a rapid shift to wetter conditions as permafrost thawed in response to climatic warming, culminating in collapse of the peat domes. Commonalities between study sites lead us to propose a five-phase model for permafrost peatland response to climatic warming. This model suggests a shared ecohydrological trajectory towards a common end point: inundated Arctic fen. Although carbon accumulation is rapid in such sites, saturated soil conditions are likely to cause elevated methane emissions that have implications for climate-feedback mechanisms

    Overriding water table control on managed peatland greenhouse gas emissions

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    Global peatlands store more carbon than is naturally present in the atmosphere1,2. However, many peatlands are under pressure from drainage-based agriculture, plantation development and fire, with the equivalent of around 3% of all anthropogenic greenhouse gases emitted from drained peatland3–5. Efforts to curb such emissions are intensifying through the conservation of undrained peatlands and rewetting of drained systems6. Here we report CO2 eddy covariance data from 16 locations and CH4 data from 41 locations in the British Isles, and combine them with published data from sites across all major peatland biomes. We find that the mean annual effective water-table depth (WTDe; that is, the average depth of the aerated peat layer) overrides all other ecosystem- and management-related controls on greenhouse gas fluxes. We estimate that every 10 cm of reduction in WTDe could reduce the net warming impact of CO2 and CH4 emissions (100-year Global Warming Potentials) by at least 3 t CO2e ha-1 yr-1, until WTDe is < 30 cm. Raising water levels further would continue to have a net cooling effect until WTDe is < 10 cm. Our results suggest that greenhouse gas emissions from peatlands drained for agriculture could be greatly reduced without necessarily halting their productive use. Halving WTDe in all drained agricultural peatlands, for example, could reduce emissions by the equivalent of over 1% of global anthropogenic emissions

    Subtype-specific differences in transmission cluster dynamics of HIV-1 B and CRF01_AE in New South Wales, Australia

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    Introduction: The human immunodeficiency virus 1 (HIV-1) pandemic is characterized by numerous distinct sub-epidemics (clusters) that continually fuel local transmission. The aims of this study were to identify active growing clusters, to understand which factors most influence the transmission dynamics, how these vary between different subtypes and how this information might contribute to effective public health responses. Methods: We used HIV-1 genomic sequence data linked to demographic factors that accounted for approximately 70% of all new HIV-1 notifications in New South Wales (NSW). We assessed differences in transmission cluster dynamics between subtype B and circulating recombinant form 01_AE (CRF01_AE). Separate phylogenetic trees were estimated using 2919 subtype B and 473 CRF01_AE sequences sampled between 2004 and 2018 in combination with global sequence data and NSW-specific clades were classified as clusters, pairs or singletons. Significant differences in demographics between subtypes were assessed with Chi-Square statistics. Results: We identified 104 subtype B and 11 CRF01_AE growing clusters containing a maximum of 29 and 11 sequences for subtype B and CRF01_AE respectively. We observed a > 2-fold increase in the number of NSW-specific CRF01_AE clades over time. Subtype B clusters were associated with individuals reporting men who have sex with men (MSM) as their transmission risk factor, being born in Australia, and being diagnosed during the early stage of infection (p 1.5 sequences / 6-months) and which consisted of a majority of infections among MSM. We also found four active growing CRF01_AE clusters containing only infections among MSM. Finally, we found 47 subtype B and seven CRF01_AE clusters that contained a large gap in time (>1 year) between infections and may be indicative of intermediate transmissions via undiagnosed individuals. Conclusions: The large number of active and growing clusters among MSM are the driving force of the ongoing epidemic in NSW for subtype B and CRF01_AE.Francesca Di Giallonardo, Angie N Pinto, Phillip Keen, Ansari Shaik, Alex Carrera, Hanan Salem, Christine Selvey, Steven J Nigro, Neil Fraser, Karen Price, Joanne Holden, Frederick J Lee, Dominic E Dwyer, Benjamin R Bavinton, Jemma L Geoghegan, Andrew E Grulich, Anthony D Kelleher, NSW HIV Prevention Partnership Project ... Mark Boyd ... et al

    Improving inpatient pharmacoterapeutic process by Lean Six Sigma methodology

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    [EN] Background Lean Six Sigma methodology has been used to improve care processes, eliminate waste, reduce costs, and increase patient satisfaction. Objective To analyse the results obtained with Lean Six Sigma methodology in the diagnosis and improvement of the inpatient pharmacotherapy process during structural and organisational changes in a tertiary hospital. Material and methods Scope: 1.000 beds tertiary hospital. Design prospective observational study. The define, measure, analyse, improve and control (DMAIC), were deployed from March to September 2011. An Initial Project Charter was updated as results were obtained. Population and sample: 131 patients with treatments prescribed within 24 h after admission and with 4 drugs. Variables: safety indicators (medication errors), and efficiency indicators (complaints and time delays). Results Proportion of patients with a medication error was reduced from 61.0% (25/41 patients) to 55.7% (39/70 patients) in four months. Percentage of errors (regarding the opportunities for error) decreased in the different phases of the process: Prescription: from 5.1% (19/372 opportunities) to 3.3% (19/572 opportunities); Preparation: from 2.7% (14/525 opportunities) to 1.3% (11/847 opportunities); and administration: from 4.9% (16/329 opportunities) to 3.0% (13/433 opportunities). Nursing complaints decreased from 10.0% (2119/21038 patients) to 5.7% (1779/31097 patients). The estimated economic impact was 76,800 euros saved. Conclusions An improvement in the pharmacotherapeutic process and a positive economic impact was observed, as well as enhancing patient safety and efficiency of the organization. Standardisation and professional training are future Lean Six Sigma candidate projects.[ES] Introducción La metodología Lean Seis Sigma se utilizó para mejorar procesos, eliminar desperdicios, reducir costes y aumentar la satisfacción de clientes. Objetivo Analizar los resultados obtenidos con la metodología Lean Seis Sigma en el diagnóstico y la mejora del proceso farmacoterapéutico del paciente hospitalizado durante el cambio estructural y organizativo de un hospital terciario. Material y métodos Ámbito: hospital general terciario con 1.000 camas. Diseño del estudio: observacional y prospectivo. Se desplegaron las etapas definir, medir, analizar, mejorar y controlar (DMAIC) entre marzo y septiembre de 2011, actualizando el Project Charter inicial según resultados. Población y muestra: 131 pacientes hospitalizados con tratamientos prescritos en las 24 h siguientes al ingreso y con 4 medicamentos. Variables: indicadores de seguridad (errores de medicación) y de eficiencia (tiempos de demora y reclamaciones). Resultados La proporción de pacientes con algún error de medicación se redujo del 61,0 (25/41 pacientes) al 55,7% (39/70 pacientes) en 4 meses. Los porcentajes de errores, con respecto a las oportunidades de error, en distintas fases del proceso disminuyeron: prescripción 5,1 (19/372) a 3,3% (19/572); preparación 2,7 (14/525) a 1,3% (11/847 oportunidades); y administración: 4,9 (16/329) a 3,0% (13/433). Las reclamaciones se redujeron del 10,0 (2.119/21.038 pacientes) a 5,7% (1.779/31.097 pacientes). El impacto económico se estimó en 76.800 euros evitados. Conclusiones Se observó una mejora del proceso farmacoterapéutico y un impacto financiero positivo que ha repercutido en la seguridad del paciente y la eficiencia de la organización. La normalización y la formación de profesionales podrían ser proyectos futuros de Lean Seis Sigma.Font Noguera, I.; Fernández Megía, M.; Ferrer, A.; Balasch Parisi, S.; Edo Solsona, M.; Poveda Andres, J. (2013). Mejora del proceso farmacoterapéutico del paciente hospitalizado mediante la metodología Lean Seis Sigma. Revista de Calidad Asistencial. 28(6):370-380. doi:10.1016/j.cali.2013.04.003S37038028
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