755 research outputs found

    UA68/6/2 Voices, Vol. VI, No. 2

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    Magazine produced by the Western Writers, a group of student readers and writers devoted to good writing and determined to encourage those interested in creative work. It presents members\u27 best efforts in other than class-assigned papers. Special edition dedicated to member Cecil Richard Oakley\u27s work. He died November 4, 1961

    Quantifying simulator discrepancy in discrete-time dynamical simulators

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    When making predictions with complex simulators it can be important to quantify the various sources of uncertainty. Errors in the structural specification of the simulator, for example due to missing processes or incorrect mathematical specification, can be a major source of uncertainty, but are often ignored. We introduce a methodology for inferring the discrepancy between the simulator and the system in discrete-time dynamical simulators. We assume a structural form for the discrepancy function, and show how to infer the maximum likelihood parameter estimates using a particle filter embedded within a Monte Carlo expectation maximization (MCEM) algorithm. We illustrate the method on a conceptual rainfall runoff simulator (logSPM) used to model the Abercrombie catchment in Australia. We assess the simulator and discrepancy model on the basis of their predictive performance using proper scoring rules

    Provenance Threat Modeling

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    Provenance systems are used to capture history metadata, applications include ownership attribution and determining the quality of a particular data set. Provenance systems are also used for debugging, process improvement, understanding data proof of ownership, certification of validity, etc. The provenance of data includes information about the processes and source data that leads to the current representation. In this paper we study the security risks provenance systems might be exposed to and recommend security solutions to better protect the provenance information.Comment: 4 pages, 1 figure, conferenc

    Experience with quality assurance in two store-and-forward telemedicine networks

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    Published version. Also available at http://dx.doi.org/10.3389/fpubh.2015.00261Despite the increasing use of telemedicine around the world, little has been done to incorporate quality assurance (QA) into these operations. The purpose of the present study was to examine the feasibility of QA in store-and-forward teleconsulting using a previously published framework. During a 2-year study period, we examined the feasibility of using QA tools in two mature telemedicine networks [Médecins Sans Frontières (MSF) and New Zealand Teledermatology (NZT)]. The tools included performance reporting to assess trends, automated follow-up of patients to obtain outcomes data, automated surveying of referrers to obtain user feedback, and retrospective assessment of randomly selected cases to assess quality. In addition, the senior case coordinators in each network were responsible for identifying potential adverse events from email reports received from users. During the study period, there were 149 responses to the patient follow-up questions relating to the 1241 MSF cases (i.e., 12% of cases), and there were 271 responses to the follow-up questions relating to the 639 NZT cases (i.e., 42% of cases). The collection of user feedback reports was combined with the collection of patient follow-up data, thus producing the same response rates. The outcomes data suggested that the telemedicine advice proved useful for the referring doctor in the majority of cases and was likely to benefit the patient. The user feedback was overwhelmingly positive, over 90% of referrers in the two networks finding the advice received to be of educational benefit. The feedback also suggested that the teleconsultation had provided cost savings in about 20% of cases, either to the patient/family, or to the hospital/clinic treating the patient. Various problems were detected by regular monitoring, and certain adverse events were identified from email reports by the users. A single aberrant quality reading was detected by using a process control chart. The present study demonstrates that a QA program is feasible in store-and-forward telemedicine, and shows that it was useful in two different networks, because certain problems were detected (and then solved) that would not have been identified until much later. It seems likely that QA could be used much more widely in telemedicine generally to benefit patient care

    Centrosome-independent mitotic spindle formation in vertebrates

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    AbstractBackground: In cells lacking centrosomes, the microtubule-organizing activity of the centrosome is substituted for by the combined action of chromatin and molecular motors. The question of whether a centrosome-independent pathway for spindle formation exists in vertebrate somatic cells, which always contain centrosomes, remains unanswered, however. By a combination of labeling with green fluorescent protein (GFP) and laser microsurgery we have been able to selectively destroy centrosomes in living mammalian cells as they enter mitosis.Results: We have established a mammalian cell line in which the boundaries of the centrosome are defined by the constitutive expression of γ-tubulin–GFP. This feature allows us to use laser microsurgery to selectively destroy the centrosomes in living cells. Here we show that this method can be used to reproducibly ablate the centrosome as a functional entity, and that after destruction the microtubules associated with the ablated centrosome disassemble. Depolymerization–repolymerization experiments reveal that microtubules form in acentrosomal cells randomly within the cytoplasm. When both centrosomes are destroyed during prophase these cells form a functional bipolar spindle. Surprisingly, when just one centrosome is destroyed, bipolar spindles are also formed that contain one centrosomal and one acentrosomal pole. Both the polar regions in these spindles are well focused and contain the nuclear structural protein NuMA. The acentrosomal pole lacks pericentrin, γ-tubulin, and centrioles, however.Conclusions: These results reveal, for the first time, that somatic cells can use a centrosome-independent pathway for spindle formation that is normally masked by the presence of the centrosome. Furthermore, this mechanism is strong enough to drive bipolar spindle assembly even in the presence of a single functional centrosome

    Effect of combustor-inlet conditions on performance of an annular turbojet combustor

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    The combustion performance, and particularly the phenomenon of altitude operational limits, was studied by operating the annular combustor of a turbojet engine over a range of conditions of air flow, inlet pressure, inlet temperature, and fuel flow. Information was obtained on the combustion efficiencies, the effect on combustion of inlet variables, the altitude operational limits with two different fuels, the pressure losses in the combustor, the temperature and velocity profiles at the combustor outlet, the extent of afterburning, the fuel-injection characteristics, and the condition of the combustor basket
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