4,138 research outputs found

    WP 2018-389

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    Recent research has found, in some groups of Americans, dramatic increases in deaths due to drug overdose and suicide and an overall stagnation of trends toward increased longevity. This study examines the link between mortality of older working age (45 to 64) adults and local economic downturns in the U.S. to evaluate the role of economic shifts in various causes of death and their related mortality trends. Specifically, we estimate regression models to test the hypotheses that the longevity effects of poor economic prospects are reflected through (1) increased suicide, drug overdose, and other “deaths of despair” and (2) other causes of death linked to exposure to economic and social stress such as heart and cerebrovascular disease. To avoid the problem of endogeneity of local economic conditions to mortality conditions, we measure the local economic shock of lost employment with predicted employment based on baseline industrial composition and national trends in employment by industry. We find evidence consistent with prior research that among non-Hispanic white adults, midlife mortality has increased since 1990, particularly among those with low educational attainment. We also find that “deaths of despair” are important contributors to that trend. However, we find that while distress in local, area economies does predict increased mortality for chronic disease, it predicts decreased mortality from suicides, opioids, and other substance abuse. This finding suggests caution in the application of the construct of despair in explaining recent mortality patterns.Social Security Adminstration, Award number RRC08098401-10, R-UM18-07https://deepblue.lib.umich.edu/bitstream/2027.42/148126/1/wp389.pdfDescription of wp389.pdf : Working pape

    An experimental and numerical study of the influence of local effects on the application of the fibre push-in tests

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    Accelerated corrosion tests, Cohesive crack, Finite Elements simulations Several methods have been developed to test interfacial adhesion in composite materials such as pull-out, microbond and push-in/push-out tests. Some of them can only be applied to single fibre matrix composites and others are difficult to perform on brittle fibres due to premature fracture of the fibre. Push-in tests, consisting on pushing the fibre with a micro or nanoindenter on a bulk specimen, constitute a powerful technique that can be applied directly on composite laminates. However, the interfacial adhesion values obtained from different tests (microbond, push in) often differ and even are subjected to a large scatter. This might be due to the fact that the existing analytical solutions that are typically used to interpret the experimental data take into account the constrain effect of the surrounding fibres on a simplified manner. To study this, we have carried out a careful micromechanical modelling of the push-in test, coupled with experimental adhesion testing in a glass fibre reinforced epoxy matrix composite. The model takes into account the interfacial fracture process by means of interface cohesive elements at the fibre–matrix interface and focuses on the study of the constrain effects due to the local configuration of the surrounding fibre

    Localized Fibrous Tumors of the Pleura: Experience With 7 Recent Cases

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    OBJECTIVE: Localized fibrous tumors of the pleura are rare. We report 7 cases and review the literature in order to define the range of clinical characteristics of these tumors, treatment options, and prognosis. METHODS: A retrospective review of 7 cases treated between 1997 and 2003, focusing on clinical presentation, diagnostic tests, and treatment. The tumor was removed surgically in all cases, by thoracotomy in 6 cases and by video-assisted thoracoscopic surgery in 1 patient. RESULTS: All patients recovered fully after surgery, with no postoperative complications. One patient experienced recurrence twice, 33 and 67 months after the initial resection. All are alive at the time of writing, after a mean follow up period of 19 months (range 1 month to 5 years and 10 months). CONCLUSIONS: The treatment of choice for a fibrous tumor of the pleura is full resection and follow up to detect possible late recurrence

    A methodology to measure the interface shear strength by means of the fiber push-in test

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    A methodology is presented to measure the fiber/matrix interface shear strength in composites. The strategy is based on performing a fiber push-in test at the central fiber of highly-packed fiber clusters with hexagonal symmetry which are often found in unidirectional composites with a high volume fraction of fibers. The mechanics of this test was analyzed in detail by means of three-dimensional finite element simulations. In particular, the influence of different parameters (interface shear strength, toughness and friction as well as fiber longitudinal elastic modulus and curing stresses) on the critical load at the onset of debonding was established. From the results of the numerical simulations, a simple relationship between the critical load and the interface shear strength is proposed. The methodology was validated in an unidirectional C/epoxy composite and the advantages and limitations of the proposed methodology are indicated

    Design, Implementation, and Empirical Validation of a Framework for Remote Car Driving Using a Commercial Mobile Network

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    Despite the fact that autonomous driving systems are progressing in terms of their automation levels, the achievement of fully self-driving cars is still far from realization. Currently, most new cars accord with the Society of Automotive Engineers (SAE) Level 2 of automation, which requires the driver to be able to take control of the car when needed: for this reason, it is believed that between now and the achievement of fully automated self-driving car systems, there will be a transition, in which remote driving cars will be a reality. In addition, there are tele-operation-use cases that require remote driving for health or safety reasons. However, there is a lack of detailed design and implementation available in the public domain for remote driving cars: therefore, in this work we propose a functional framework for remote driving vehicles. We implemented a prototype, using a commercial car. The prototype was connected to a commercial 4G/5G mobile network, and empirical experiments were conducted, to validate the prototype’s functions, and to evaluate its performance in real-world driving conditions. The design, implementation, and empirical evaluation provided detailed technical insights into this important research and innovation area.This research was funded in part by the EU Horizon 2020 5G-PPP 5G-INDUCE project (“Open cooperative 5G experimentation platforms for the industrial sector NetApps”) under grant number H2020-ICT-2020-2/101016941, by the EU Horizon Europe INCODE project (“Programming platform for intelligent collaborative deployments over heterogeneous edge-IoT environments”) under grant number HORIZON-CL4-2022-DATA-01-03/101093069, and by the EU Horizon Europe project INCODE: programming platform for intelligent collaborative deployments over heterogeneous edge-IoT environments (HORIZON-CL4-2022-DATA-01-03/101093069)

    An experimental and Numerical Study of the Influence of local Effects on the applications of the fibre push-in test

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    Several methods, such as pull-out, microbond and push-in/push-out tests, have been developed to test interfacial adhesion in composite materials. Some of them can only be applied to single-fibre matrix composites, like the microbond test, and others are difficult to perform on brittle fibres due to premature fracture of the fibre. Push-in tests, consisting of pushing the fibre with a micro- or nanoindenter on a bulk specimen, constitute a powerful technique that can be applied directly to composite laminates. However, the interfacial adhesion values obtained from different tests (microbond, push-in) often differ and even the results from one type of test are subjected to a large scatter. This might be due to the fact that the existing analytical solutions that are typically used to interpret the experimental data take into account the constraining effect of the surrounding fibres on a simplified manner. To study interfacial adhesion and the effect of the constraint of the neighbouring fibres, a micromechanical model of the push-in test was developed, coupled with experimental adhesion testing in a glass fibre-reinforced epoxy matrix composite. The model takes into account the interfacial fracture process by means of interface cohesive elements at the fibre–matrix interface and focusses on the study of the constraining effects due to the local configuration of the surrounding fibres

    Investigation of the CRT performance of a PET scanner based in liquid xenon: a Monte Carlo study

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    The measurement of the time of flight of the two 511 keV gammas recorded in coincidence in a PET scanner provides an effective way of reducing the random background and therefore increases the scanner sensitivity, provided that the coincidence resolving time (CRT) of the gammas is sufficiently good. Existing commercial systems based in LYSO crystals, such as the GEMINIS of Philips, reach CRT values of 600 ps (FWHM). In this paper we present a Monte Carlo investigation of the CRT performance of a PET scanner exploiting the scintillating properties of liquid xenon. We find that an excellent CRT of 60 70 ps (depending on the PDE of the sensor) can be obtained if the scanner is instrumented with silicon photomultipliers (SiPMs) sensitive to the ultraviolet light emitted by xenon. Alternatively, a CRT of 120 ps can be obtained instrumenting the scanner with (much cheaper) blue-sensitive SiPMs coated with a suitable wavelength shifter. These results show the excellent time of flight capabilities of a PET device based in liquid xenon.The authors acknowledge support from the following agencies and institutions: the European Research Council (ERC) under the Advanced Grant 339787-NEXT, the Ministerio de Economia y Competitividad and FEDER of Spain, the Severo Ochoa Program SEV-2014-0398 and GVA under grant PROMETEO/2016/120; we acknowledge enlightening discussions with J. Varela and C. Lerche.GĂłmez-Cadenas, JJ.; Benlloch-Rodriguez, JM.; Ferrario, P.; Monrabal, F.; Rodriguez-Samaniego, J.; Toledo AlarcĂłn, JF. (2016). Investigation of the CRT performance of a PET scanner based in liquid xenon: a Monte Carlo study. Journal of Instrumentation. 11(P09011). https://doi.org/10.1088/1748-0221/11/09/P09011S11P0901

    Variabilidad en la presentaciĂłn del SĂ­ndrome de Brown-McLean

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    Case report: We report two aphakic patients with Brown-McLean syndrome. Discussion: One patient was affected by Marfan syndrome, after having undergone lens subluxation surgery and aphakia 23 years previously. The other patient was aphakic due to cataract surgery with complications three years before. Our cases demonstrate that this syndrome can show a variety of clinical characteristics, but peripheral corneal edema is always present. A full understanding of the clinical signs of presentation is of great importance in order to detect this syndrom
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