1,830 research outputs found

    Evaluation of high pressure water blast with rotating spray bar for removing paint and rubber deposits from airport runways, and review of runway slipperiness problems created by rubber contamination

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    A high pressure water blast with rotating spray bar treatment for removing paint and rubber deposits from airport runways is studied. The results of the evaluation suggest that the treatment is very effective in removing above surface paint and rubber deposits to the point that pavement skid resistance is restored to trafficked but uncontaminated runway surface skid resistance levels. Aircraft operating problems created by runway slipperiness are reviewed along with an assessment of the contributions that pavement surface treatments, surface weathering, traffic polishing, and rubber deposits make in creating or alleviating runway slipperiness. The results suggest that conventional surface treatments for both portland cement and asphaltic concrete runways are extremely vulnerable to rubber deposit accretions which can produce runway slipperiness conditions for aircraft operations as or more slippery than many snow and ice-covered runway conditions. Pavement grooving surface treatments are shown to be the least vulnerable to rubber deposits accretion and traffic polishing of the surface treatments examined

    A Comparative Study of the ReCellÂŽ Device and Autologous Spit-Thickness Meshed Skin Graft in the Treatment of Acute Burn Injuries.

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    Early excision and autografting are standard care for deeper burns. However, donor sites are a source of significant morbidity. To address this, the ReCell® Autologous Cell Harvesting Device (ReCell) was designed for use at the point-of-care to prepare a noncultured, autologous skin cell suspension (ASCS) capable of epidermal regeneration using minimal donor skin. A prospective study was conducted to evaluate the clinical performance of ReCell vs meshed split-thickness skin grafts (STSG, Control) for the treatment of deep partial-thickness burns. Effectiveness measures were assessed to 1 year for both ASCS and Control treatment sites and donor sites, including the incidence of healing, scarring, and pain. At 4 weeks, 98% of the ASCS-treated sites were healed compared with 100% of the Controls. Pain and assessments of scarring at the treatment sites were reported to be similar between groups. Significant differences were observed between ReCell and Control donor sites. The mean ReCell donor area was approximately 40 times smaller than that of the Control (P < .0001), and after 1 week, significantly more ReCell donor sites were healed than Controls (P = .04). Over the first 16 weeks, patients reported significantly less pain at the ReCell donor sites compared with Controls (P ≤ .05 at each time point). Long-term patients reported higher satisfaction with ReCell donor site outcomes compared with the Controls. This study provides evidence that the treatment of deep partial-thickness burns with ASCS results in comparable healing, with significantly reduced donor site size and pain and improved appearance relative to STSG

    A direct path to dependable software

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    What would it take to make software more dependable? Until now, most approaches have been indirect: some practices – processes, tools or techniques – are used that are believed to yield dependable software, and the argument for dependability rests on the extent to which the developers have adhered to them. This article argues instead that developers should produce direct evidence that the software satisfies its dependability claims. The potential advantages of this approach are greater credibility (since the argument is not contingent on the effectiveness of the practices) and reduced cost (since development resources can be focused where they have the most impact)

    Re-Instatement Of Pell Grants For Incarcerated Students: Implications For CS Education

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    The US incarcerates more people, and at a higher rate, than any other country in the world—predominantly low-income people of color. Higher education in prison (HEP) has a powerful impact on justice-impacted people, improving their quality of life during incarceration and reducing their likelihood of returning to prison post-release. HEP nearly disappeared in 1994 after Pell Grant eligibility was eliminated for incarcerated students, which was recently reinstated. More computing educators can reach incarcerated students with digital literacy skills, core computing content, and critical analyses of the impacts of computing on society. CS education researchers can also support the growth of CS education in prisons, and influence policies restricting technology infrastructure

    Spintronics: Fundamentals and applications

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    Spintronics, or spin electronics, involves the study of active control and manipulation of spin degrees of freedom in solid-state systems. This article reviews the current status of this subject, including both recent advances and well-established results. The primary focus is on the basic physical principles underlying the generation of carrier spin polarization, spin dynamics, and spin-polarized transport in semiconductors and metals. Spin transport differs from charge transport in that spin is a nonconserved quantity in solids due to spin-orbit and hyperfine coupling. The authors discuss in detail spin decoherence mechanisms in metals and semiconductors. Various theories of spin injection and spin-polarized transport are applied to hybrid structures relevant to spin-based devices and fundamental studies of materials properties. Experimental work is reviewed with the emphasis on projected applications, in which external electric and magnetic fields and illumination by light will be used to control spin and charge dynamics to create new functionalities not feasible or ineffective with conventional electronics.Comment: invited review, 36 figures, 900+ references; minor stylistic changes from the published versio

    Engaging the Periphery for Visual Communication on Mobile Phones

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    While mobile phones have become ubiquitous instruments of communication and social interaction, they still require explicit interaction, placing high demands on attention. Engaging the periphery of users’ attention offers opportunities for awareness and interaction while reducing demands on attention and risks of disruption. We explore the mobile peripheral design space with Emotipix, an application for camera phones that turns the background of the phone’s display into a place for visual conversations. We conducted an exploratory 2-week user study with 6 pairs and one 4-person group, and found that Emotipix facilitated ongoing social practices. Our study shows that there is an unexploited opportunity to use mobile phones for peripheral awareness. We provide recommendations for managing users ’ expectations, desires for control, and privacy in mobile peripheral display design. 1

    Covert Neurological Symptoms Associated With Silent Infarcts From Midlife to Older Age: The Atherosclerosis Risk in Communities Study

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    Unrecognized or unreported stroke-like symptoms, called covert symptoms, occur in persons free of clinical stroke. Whether covert symptoms are associated with subclinical brain infarcts (SBI) is unknown. This study examined the association between covert stroke-like symptoms and SBI/stroke in persons with no history of stroke or TIA
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