1,663 research outputs found

    Reference Avionics Architecture for Lunar Surface Systems

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    Developing and delivering infrastructure capable of supporting long-term manned operations to the lunar surface has been a primary objective of the Constellation Program in the Exploration Systems Mission Directorate. Several concepts have been developed related to development and deployment lunar exploration vehicles and assets that provide critical functionality such as transportation, habitation, and communication, to name a few. Together, these systems perform complex safety-critical functions, largely dependent on avionics for control and behavior of system functions. These functions are implemented using interchangeable, modular avionics designed for lunar transit and lunar surface deployment. Systems are optimized towards reuse and commonality of form and interface and can be configured via software or component integration for special purpose applications. There are two core concepts in the reference avionics architecture described in this report. The first concept uses distributed, smart systems to manage complexity, simplify integration, and facilitate commonality. The second core concept is to employ extensive commonality between elements and subsystems. These two concepts are used in the context of developing reference designs for many lunar surface exploration vehicles and elements. These concepts are repeated constantly as architectural patterns in a conceptual architectural framework. This report describes the use of these architectural patterns in a reference avionics architecture for Lunar surface systems elements

    Clinical and Demographic Predictors of Interdisciplinary Chronic Pain Rehabilitation Program Treatment Response

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    © 2019 the American Pain Society Patients treated in interdisciplinary chronic pain rehabilitation programs show long-term improvements in symptoms; however, outcomes may vary across heterogenous patient subpopulations. This longitudinal retrospective study characterizes the influence of opioids, mood, patient characteristics, and baseline symptoms on pain and functional impairment (FI) in 1,681 patients 6-months to 12-months post-treatment in an interdisciplinary chronic pain rehabilitation program incorporating opioid weaning. Linear mixed models showed immediate and durable treatment benefits with nonuniform worsening at follow up which slowed over time. Latent class growth analysis identified three post-treatment trajectories of pain and FI: mild symptoms and durable benefits, moderate symptoms and durable benefits, and intractable symptoms. A fourth pain trajectory showed immediate post-treatment improvement and worsening at follow up. Whether a patient was weaned from opioids was not predictive of treatment trajectory. Racial ethnic minority status, higher levels of post-treatment depression, and lower perceived treatment response were associated with less resolution (moderate symptoms) or intractable symptoms. Not having a college education was predictive of intractable or worsening pain and a moderate course of FI. Older age and male gender was associated with intractable FI. Treatment outcomes may be improved by the development of targeted interventions for patients at risk of poor recovery and/or deteriorating long-term course. Perspective: This study examined predictors of treatment response in 1,681 patients treated in an interdisciplinary chronic pain rehabilitation program incorporating opioid weaning. Opioid weaning did not predict outcome. Higher levels of symptoms, lower levels of education, and being a racial-ethnic minority were associated with a less salubrious long-term treatment response

    Dynamics of B-Cell Populations in CSF and Blood in Patients Treated with a Combination of Rituximab and Mitoxantrone.

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    Background. Mitoxantrone (MTX) and Rituximab (RTX) are successfully used for treatment of multiple sclerosis (MS) and can be combined to increase efficacy. Objective. We used MTX, RTX, and methylprednisolone in a single combined regiment and observed patients prospectively. Methods. We present results of observational pilot study of combined therapy of RTX and MTX in 28 patients with active MS. Therapeutic protocol consisted of two infusions within 14 days. First infusion was 1000 mg methylprednisolone (MP) IV, 1000 mg RTX IV, and 20 mg MTX IV. On day 14, 1000 mg MP IV and 1000 mg RTX IV were given. Patients were followed prospectively from 12 to 48 months. Results and Conclusion. There were no relapses among all 28 patients during the observation period. B-cell depletion of CD19+ and CD19+/CD27+ memory B-cell subpopulation in both compartments was confirmed in all patients at 6 months. We found a more rapid reconstitution of B cells in the CSF than in the peripheral blood and longstanding depression of CD19+CD27+ memory B-cell. Conclusion. Effectiveness of combined regimen of RTX and MTX could be related to longstanding depletion of CD19+CD27+ memory B-cell subset

    History of formation and development of toxicology

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    The article reveals the general problems of the history of toxicology and its formation as a science. The periodization of toxicology is given, the peculiarities of each stage are noted, and the conclusion is made about the importance of toxicology in the development of medicine.В статье раскрываются общие проблемы истории токсикологии и её становления как науки. Даётся периодизация токсикологии, отмечаются особенности каждого этапа и делается вывод о значении токсикологии в развитии медицины

    Multiscale modelling of vascular tumour growth in 3D: the roles of domain size & boundary condition

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    We investigate a three-dimensional multiscale model of vascular tumour growth, which couples blood flow, angiogenesis, vascular remodelling, nutrient/growth factor transport, movement of, and interactions between, normal and tumour cells, and nutrient-dependent cell cycle dynamics within each cell. In particular, we determine how the domain size, aspect ratio and initial vascular network influence the tumour's growth dynamics and its long-time composition. We establish whether it is possible to extrapolate simulation results obtained for small domains to larger ones, by constructing a large simulation domain from a number of identical subdomains, each subsystem initially comprising two parallel parent vessels, with associated cells and diffusible substances. We find that the subsystem is not representative of the full domain and conclude that, for this initial vessel geometry, interactions between adjacent subsystems contribute to the overall growth dynamics. We then show that extrapolation of results from a small subdomain to a larger domain can only be made if the subdomain is sufficiently large and is initialised with a sufficiently complex vascular network. Motivated by these results, we perform simulations to investigate the tumour's response to therapy and show that the probability of tumour elimination in a larger domain can be extrapolated from simulation results on a smaller domain. Finally, we demonstrate how our model may be combined with experimental data, to predict the spatio-temporal evolution of a vascular tumour

    Population pharmacokinetics of meropenem administered as a prolonged infusion in children with cystic fibrosis

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    OBJECTIVES: Meropenem is frequently used to treat pulmonary exacerbations in children with cystic fibrosis (CF) in the USA. Prolonged-infusion meropenem improves the time that free drug concentrations remain above the MIC (fT> MIC) in adults, but data in CF children are sparse. We describe the population pharmacokinetics, tolerability and treatment burden of prolonged-infusion meropenem in CF children. METHODS: Thirty children aged 6-17 years with a pulmonary exacerbation received 40 mg/kg meropenem every 8 h; each dose was administered as a 3 h infusion. Pharmacokinetics were determined using population methods in Pmetrics. Monte Carlo simulation was employed to compare 0.5 with 3 h infusions to estimate the probability of pharmacodynamic target attainment (PTA) at 40% fT> MIC. NCT#01429259. RESULTS: A two-compartment model fitted the data best with clearance and volume predicted by body weight. Clearance and volume of the central compartment were 0.41 ± 0.23 L/h/kg and 0.30 ± 0.17 L/kg, respectively. Half-life was 1.11 ± 0.38 h. At MICs of 1, 2 and 4 mg/L, PTAs for the 0.5 h infusion were 87.6%, 70.1% and 35.4%, respectively. The prolonged infusion increased PTAs to >99% for these MICs and achieved 82.8% at 8 mg/L. Of the 30 children, 18 (60%) completed treatment with prolonged infusion; 5 did so at home without any reported burden. Nine patients were changed to a 0.5 h infusion when discharged home. CONCLUSIONS: In these CF children, meropenem clearance was greater compared with published values from non-CF children. Prolonged infusion provided an exposure benefit against pathogens with MICs ≥1 mg/L, was well tolerated and was feasible to administer in the hospital and home settings, the latter depending on perception and family schedule
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