25,012 research outputs found
Study of early nausea and vomiting response of swine to ionizing radiation Final technical progress report, 15 Sep. - 12 Dec. 1969
Early nausea and vomiting response of swine to ionizing radiation related to radiation dosage and effect on humans in space mission
Efficient diagnosis of multiprocessor systems under probabilistic models
The problem of fault diagnosis in multiprocessor systems is considered under a probabilistic fault model. The focus is on minimizing the number of tests that must be conducted in order to correctly diagnose the state of every processor in the system with high probability. A diagnosis algorithm that can correctly diagnose the state of every processor with probability approaching one in a class of systems performing slightly greater than a linear number of tests is presented. A nearly matching lower bound on the number of tests required to achieve correct diagnosis in arbitrary systems is also proven. Lower and upper bounds on the number of tests required for regular systems are also presented. A class of regular systems which includes hypercubes is shown to be correctly diagnosable with high probability. In all cases, the number of tests required under this probabilistic model is shown to be significantly less than under a bounded-size fault set model. Because the number of tests that must be conducted is a measure of the diagnosis overhead, these results represent a dramatic improvement in the performance of system-level diagnosis techniques
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What is a Freestanding Emergency Department? Definitions Differ Across Major United States Data Sources
Introduction: Despite the growing number of freestanding emergency departments (FSED) in the United States (US), FSED definitions differ across major US data sources of healthcare facilities and use. We compare these sources and propose a universal definition of FSED (and its two major types) to improve communications regarding these facilities and their patients.Methods: We collected definitions of FSEDs from 11 national data sources using their websites, email, and telephone communications. For each source, we asked how they define FSEDs, whether being open 24/7 is a requirement to be called an ED, and whether they maintain a dataset of FSEDs.Results: Definitions varied across the data sources. All sources recognize FSEDs in their definitions, regardless of type; only one (the National Health Intervew Survey) does not differentiate them from other EDs. Five of the 11 sources (45%) omit autonomous FSEDs from their definitions and do not separately identify satellite FSEDs from their affiliated hospitals. One source does separately identify satellite FSEDs from their affiliated hospitals, but also omits autonomous FSEDs. Furthermore, three of the 11 sources (27%) do not require being open 24/7, while all others (73%) employ this criterion. Six of the 11 (55%) maintain datasets of FSEDs using their definition.Conclusion: As FSEDs continue to change the landscape of emergency care, it is important that they also be represented in national ED data sources. The current differences in the definition of an FSED make it difficult to provide accurate and longitudinal analysis for these facilities and patients who receive services at these facilities. We propose a universal definition of FSEDs as described by both the American College of Emergency Physicians and the National Emergency Department Inventory. Implementing a standard definition would facilitate a more accurate representation of FSEDs in national data sources and enhance ongoing efforts to improve the quality of emergency care delivered in FSEDs
Optimal uncertainty quantification for legacy data observations of Lipschitz functions
We consider the problem of providing optimal uncertainty quantification (UQ)
--- and hence rigorous certification --- for partially-observed functions. We
present a UQ framework within which the observations may be small or large in
number, and need not carry information about the probability distribution of
the system in operation. The UQ objectives are posed as optimization problems,
the solutions of which are optimal bounds on the quantities of interest; we
consider two typical settings, namely parameter sensitivities (McDiarmid
diameters) and output deviation (or failure) probabilities. The solutions of
these optimization problems depend non-trivially (even non-monotonically and
discontinuously) upon the specified legacy data. Furthermore, the extreme
values are often determined by only a few members of the data set; in our
principal physically-motivated example, the bounds are determined by just 2 out
of 32 data points, and the remainder carry no information and could be
neglected without changing the final answer. We propose an analogue of the
simplex algorithm from linear programming that uses these observations to offer
efficient and rigorous UQ for high-dimensional systems with high-cardinality
legacy data. These findings suggest natural methods for selecting optimal
(maximally informative) next experiments.Comment: 38 page
Differential proteolysis of insulin-like growth factor binding protein-1 (IGFBP-1) in pregnancy
The insulin-like growth factors and their binding proteins are important for placental and foetal growth. In this study, we have investigated the presence of proteolytic activity directed against insulin-like growth factor binding protein-1 (IGFBP-1) in pregnancy. In addition, the effect of protease activity on IGFBP-1 immunoreactivity and IGF binding was characterised. 125I-IGFBP-1 was incubated with maternal and foetal serum, amniotic fluid and placental extracts. Breakdown of 125I-IGFBP-1 was determined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and autoradiography. The size distribution of endogenous IGFBP-1 was determined by Western immunoblotting. Protease inhibitor studies characterised the proteolytic activity, and Western ligand blotting with 125I-IGF-I was used to determine IGF binding capacity of proteolysed IGFBP-1. Amniotic fluid samples collected after labour onset contained proteolytic activity that generated 12- and 19-kDa IGFBP-1 fragments that did not bind to 125I-IGF-I. This activity was not detected in amniotic fluid collected prior to labour onset or in other tissues. Activity was blocked by aprotinin, leupeptin, phenyl methyl sulphonyl fluoride, and Kunitz soybean trypsin inhibitor but not by ethylene diamine tetraacetic acid or pepstatin. Incubation of IGFBP-1 with trypsin generated fragments of a similar size to the amniotic fluid protease. In conclusion, we have demonstrated the presence in vivo of a trypsin-like proteolytic activity that alters the IGF-binding function of IGFBP-1 in pregnancy
Simple processors of star tracker commands for stabilizing an inertially oriented satellite
Simple processors of star tracker commands for stabilizing inertially oriented satellit
Influence of chronic restraint on gastrointestinal function in the rat Final technical report
Chronic restraint effects on body weights and gastrointestinal movements of rats on normal, low fat, and high diets with and without exposure to cobalt 6
Properties of nonaqueous electrolytes Quarterly report, 20 Dec. 1966 - 19 Mar. 1967
Properties of nonaqueous electrolytes - preparation of electrolytes, nuclear magnetic resonance structural studies, and physical property determination
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