353 research outputs found

    Augmented Reality Application Utility For Aviation Maintenance Work Instruction

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    Current aviation maintenance work instructions do not display information effectively enough to prevent costly errors and safety concerns. Aircraft are complex assemblies of highly interrelated components that confound troubleshooting and can make the maintenance procedure difficult (Drury & Gramopadhye, 2001). The sophisticated nature of aircraft maintenance necessitates a revolutionized training intervention for aviation maintenance technicians (United States General Accounting Office, 2003). Quite simply, the paper based job task cards fall short of offering rapid access to technical data and the system or component visualization necessary for working on complex integrated aircraft systems. Possible solutions to this problem include upgraded standards for paper based task cards and the use of integrated 3D product definition used on various mobile platforms (Ropp, Thomas, Lee, Broyles, Lewin, Andreychek, & Nicol, 2013). Previous studies have shown that incorporation of 3D graphics in work instructions allow the user to more efficiently and accurately interpret maintenance information (Jackson & Batstone, 2008). For aircraft maintenance workers, the use of mobile 3D model-based task cards could make current paper task card standards obsolete with their ability to deliver relevant, synchronized information to and from the hangar. Unlike previous versions of 3D model-based definition task cards and paper task cards, which are currently used in the maintenance industry, 3D model based definition task cards have the potential to be more mobile and accessible. Utilizing augmented reality applications on mobile devices to seamlessly deliver 3D product definition on mobile devices could increase the efficiency, accuracy, and reduce the mental workload for technicians when performing maintenance tasks (Macchiarella, 2004). This proposal will serve as a literary review of the aviation maintenance industry, the spatial ability of maintenance technicians, and benefits of modern digital hardware to educate, point out gaps in research, and observe possible foundations on which to build the future of aviation maintenance job task cards leading to a the methodology of the proposed study

    Minimally Invasive Ultrasound‐Guided Carpal Tunnel Release: Preliminary Clinical Results

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146278/1/jum14618.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146278/2/jum14618_am.pd

    The retinal hypercircuit: a repeating synaptic interactive motif underlying visual function

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    The vertebrate retina generates a stack of about a dozen different movies that represent the visual world as dynamic neural images or movies. The stack is embodied as separate strata that span the inner plexiform layer (IPL). At each stratum, ganglion cell dendrites reach up to read out inhibitory interactions between three different amacrine cell classes that shape bipolar-to-ganglion cell transmission. The nexus of these five cell classes represents a functional module, a retinal 'hypercircuit', that is repeated across the surface of each of the dozen strata that span the depth of the IPL. Individual differences in the characteristics of each cell class at each stratum lead to the unique processing characteristics of each neural image throughout the stack. This review shows how the interactions between the morphological and physiological characteristics of each cell class generate many of the known retinal visual functions including motion detection, directional selectivity, local edge detection, looming detection, object motion and looming detection

    General features of inhibition in the inner retina

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    Visual processing starts in the retina. Within only two synaptic layers, a large number of parallel information channels emerge, each encoding a highly processed feature like edges or the direction of motion. Much of this functional diversity arises in the inner plexiform layer, where inhibitory amacrine cells modulate the excitatory signal of bipolar and ganglion cells. Studies investigating individual amacrine cell circuits like the starburst or A17 circuit have demonstrated that single types can possess specific morphological and functional adaptations to convey a particular function in one or a small number of inner retinal circuits. However, the interconnected and often stereotypical network formed by different types of amacrine cells across the inner plexiform layer prompts that they should be also involved in more general computations. In line with this notion, different recent studies systematically analysing inner retinal signalling at a population level provide evidence that general functions of the ensemble of amacrine cells across types are critical for establishing universal principles of retinal computation like parallel processing or motion anticipation. Combining recent advances in the development of indicators for imaging inhibition with large-scale morphological and genetic classifications will help to further our understanding of how single amacrine cell circuits act together to help decompose the visual scene into parallel information channels. In this review, we aim to summarise the current state-of-the-art in our understanding of how general features of amacrine cell inhibition lead to general features of computation

    Temporally correlated expression of nAChR genes during development of the mammalian retina

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    In situ hybridizations and RNase protection assays have been used to characterize nicotinic acetylcholine receptor (nAChR) gene expression in the developing and adult rat retina. At the earliest time examined (embryonic day 13) a low level of [alpha]-3 and [beta]-4 gene expression could be detected. During the next 48 hr there was a dramatic induction of the [alpha]-3, [alpha]-4, [beta]-2, [beta]-3 and [beta]-4 genes in the recently differentiated retinal ganglion cells. By post-natal day 4 we detected nAChR gene expression in the inner nuclear layer. In the adult retina, in situ hybridizations showed these genes are expressed by cells residing in the ganglion and inner nuclear layers. These results suggest a common regulatory mechanism for the induction of nAChR expression in retinal ganglion cells during development. In addition, the variety of nAChR genes expressed in the retina imply a relatively large number of different types of nAChRs can be expressed by these cells.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/30138/1/0000515.pd

    Super-stereotypy I: Enhancement of a complex movement sequence by systemic dopamine D1 agonists

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    Peripheral administration of D1 dopamine agonists elicits grooming behavior from rodents. The present study examined grooming behavior and the relative probability and stereotypy of a natural sequence of grooming movements (called a syntactic grooming chain) that follows a predictable fixed pattern of serial order. We compared the amount of grooming behavior vs. the stereotypy of sequential patterns after peripheral administration of either a partial D1 agonist (SKF 38393; 2.5, 5.0, 10, 20 mg/kg), a full D1 agonist (SKF 82958; 0.1, 0.2, 0.5, 1.0 mg/kg; i.p.), a D2 agonist (quinpirole; 5.0, 10 mg/kg), or ACTH (2.0, 5.0 mg/kg). There was a dissociation between the elicited grooming amount, the pattern frequency, and the pattern completion or sequential stereotypy after these drugs. Quinpirole and ACTH both reduced the likelihood that the sequential pattern would be completed in the normal pattern (and reduced the overall amount of grooming). Administration of either SKF 38393 or SKF 82958 increased the tendency to engage in complex stereotyped sequential patterns of grooming (even though only the partial D1 agonist increased the total amount of grooming). In addition, SKF 38393 increased the sequential stereotypy of the already-stereotyped pattern itself (as measured by the probability of completing the stereotyped sequence once it began). Thus, dopamine D1 receptor activation appears to contribute to a kind of sequential super-stereotypy in which a complex, stereotyped behavioral sequence is initiated more frequently and more often goes to completion. Synapse 37:194–204, 2000. © 2000 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34987/1/3_ftp.pd
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