16 research outputs found

    Shuttle program: OFT ascent/descent ancillary data requirements document

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    Requirements are presented for the ascent/descent (A/D) navigation and attitude-dependent ancillary data products to be generated for the space shuttle orbiter in support of the orbital flight test (OFT) flight test requirements, MPAD guidance and navigation performance assessment, and the mission evaluation team. The A/D ancillary data support for OFT mission evaluation activities is confined to providing postflight position, velocity, attitude, and associated navigation and attitude derived parameters for the Orbiter over particular flight phases and time intervals

    Evidence of Vortices on the Insulating Side of the Superconductor-Insulator Transition

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    The magnetoresistance of ultrathin insulating films of Bi has been studied with magnetic fields applied parallel and perpendicular to the plane of the sample. Deep in the strongly localized regime, the magnetoresistance is negative and independent of field orientation. As film thicknesses increase, the magnetoresistance becomes positive, and a difference between values measured in perpendicular and parallel fields appears, which is a linear function of the magnetic field and is positive. This is not consistent with the quantum interference picture. We suggest that it is due to vortices present on the insulating side of the superconductor-insulator transition.Comment: 4 pages, 3 figure

    Learning multiple rules simultaneously: affixes are more salient than reduplications

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    Language learners encounter numerous opportunities to learn regularities, but need to decide which of these regularities to learn, because some are not productive in their native language. Here, we present an account of rule learning based on perceptual and memory primitives (Endress, Dehaene-Lambertz, & Mehler, 2007; Endress, Nespor, & Mehler, 2009), suggesting that learners preferentially learn regularities that are more salient to them, and that the pattern of salience reflects the frequency of language features across languages. We contrast this view with previous artificial grammar learning research, which suggests that infants “choose” the regularities they learn based on rational, Bayesian criteria (Frank & Tenenbaum, 2011; Gerken, 2006, 2010). In our experiments, adult participants listened to syllable strings starting with a syllable reduplication and always ending with the same “a!x” syllable, or to syllable strings starting with this “a!x” syllable and ending with the “reduplication.” Both a!xation and reduplication are frequently used for morphological marking across languages. We find three crucial results. First, participants learned both regularities simultaneously. Second, a!xation regularities seemed easier to learn than reduplication regularities. Third, regularities in sequence o↵sets were easier to learn than regularities at sequence onsets. We show that these results are inconsistent with previous Bayesian rule learning models, but mesh well with the perceptual or memory primitives view. Further, we show that the pattern of salience revealed in our experiments reflects the distribution of regularities across languages. Ease of acquisition might thus be one determinant of the frequency of regularities across languages

    Treatment Delay in Patients Undergoing Headache Surgery (Nerve Decompression Surgery)

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    Summary: Background: Although headache surgery has been shown to be an effective treatment option for refractory headache disorders, it has not been included as part of the headache disorder management algorithm by non-surgical providers. This study aims to evaluate the delay in surgical management of patients with headache disorders. In addition, a cost comparison analysis between conservative and operative treatment of headache disorders was performed, and the surgical outcomes of headache surgery were reported. Methods: Among 1112 patients who were screened, 271 (56%) patients underwent headache surgery. Data regarding the onset of headache disorder and pre- and postoperative pain characteristics were prospectively collected. To perform a cost comparison analysis, direct and indirect costs associated with the conservative treatment of headache disorders were calculated. Results: The median duration between onset of headache disorder symptoms and headache surgery was 20 (8.2-32) years. The annual mean cost of conservative treatment of headache disorders was 49,463.78(49,463.78 (30,933.87-66,553.70)perpatient.Overthe20yeartimeperiodbeforesurgery,themeancostwas66,553.70) per patient. Over the 20-year time period before surgery, the mean cost was 989,275.65 (618,677.31618,677.31-1,331,073.99). In comparison, the mean cost of headache surgery was $11,000. The median pain days per month decreased by 16 (0-25) (p<0.001), the median pain intensity reduced by 4 (2-7) (p<0.001), and the median pain duration decreased by 11 hours (0-22) (p<0.001). Conclusion: This study shows that patients experience symptoms of headache disorders for an average of 20 years prior to undergoing headache surgery. Surgical treatment not only significantly improves headache pain but also reduces healthcare costs and should be implemented in the management algorithm of headache disorders

    Use of Emerging 3D Printing and Modeling Technologies in the Health Domain

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    Three-Dimensional (3D) technologies emerged from the technological advances in manufacturing required to produce physical versions of digital models. The most attractive feature of 3D technologies is that virtual models are easy to mold, and custom-made items can be physically produced. Health domains are areas in which 3D technologies have been applied, and several studies have been conducted assessing the usefulness of such technologies in those domains. In this paper we present the results of a Systematic Literature Review (SLR) on the applications of 3D technologies in the health domain. Discussion from the revision of 33 papers is presented. The main finding of this SLR is that none of the available research papers are focused on computer science related areas (i.e., all papers are published by doctors or researchers in Medicine). Moreover, all the included papers were published in journals specialized in Medicine. Therefore, they do not delve in the computational conclusions of the studies. In this article, we identified significant research gaps (from the computational perspective), as well as new ideas are being proposed on the future of 3D technologies in health.Universidad de Costa Rica/[834-B6-076]/VINV/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ingeniería::Centro de Investigaciones en Tecnologías de Información y Comunicación (CITIC
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