385 research outputs found

    Effects of the vibrating capsule on colonic circadian rhythm and bowel symptoms in chronic idiopathic constipation

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    BackgroundConstipated patients remain dissatisfied with current treatments suggesting a need for alternative therapies.AimEvaluate the mechanistic effects of oral vibrating capsule in chronic idiopathic constipation (CIC) by examining the temporal relationships between the onset of vibrations, complete spontaneous bowel movements (CSBM), and circadian rhythm.MethodsIn post hoc analyses of two double‐blind studies, CIC patients (Rome III) were randomized to receive 5 active or sham capsules/week for 8 weeks. The capsules were programmed for single vibration (study 1) or two vibration sessions with two modes, 8 hours apart (study 2). Daily electronic diaries assessed stool habit and percentage of CSBMs associated with vibrations. Responders were patients with ≥ 1 CSBM per week over baseline.Results250 patients were enrolled (active = 133, sham = 117). During and within 3 hours of vibration, there were significantly more % CSBMs in the active vs. sham group (50% vs. 42%; P = .0018). In study 2, there were two CSBM peaks associated with vibration sessions. Significantly more % CSBMs occurred in active mode 1 (21.5%) vs. sham (11.5%); (P = .0357). Responder rates did not differ in study 1 (active vs. sham: 26.9% vs. 35.9%, P = .19) or study 2 (mode 1 vs. sham: 50% vs. 31.8%, P = .24; mode 2 vs. sham: 38.1% vs. 31.8%, P = .75). Device was well‐tolerated barring mild vibration sensation.ConclusionsVibrating capsule may increase CSBMs possibly by enhancing the physiologic effects of waking and meals, and augmenting circadian rhythm, although responder rate was not different from sham. Two vibration sessions were associated with more CSBMs.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/163488/2/nmo13890.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/163488/1/nmo13890_am.pd

    Multiple vantage points of the common operational picture: Supporting International Teamwork

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    This paper summarizes multiple perspectives of the common operational picture (COP) in military and civilian crisis management domains viewed from three vantage points: historical, conceptual, and practical. The term COP extends prior research on large group displays to describe a visual representation of tactical, operational, and strategic information intended to generate situation awareness. We present four strata of interest to formulate an innovative conceptual framework of the COP based on user-team needs: structure, representation, processes, and management. This conceptual framework is applied as part of a review of recent and ongoing projects that examines current research gaps in the application of geographic information systems (GIS) to international humanitarian response

    Clinically Significant Gains in Skillful Grasp Coordination by an Individual With Tetraplegia Using an Implanted Brain-Computer Interface With Forearm Transcutaneous Muscle Stimulation

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    © 2019 American Congress of Rehabilitation Medicine Objective: To demonstrate naturalistic motor control speed, coordinated grasp, and carryover from trained to novel objects by an individual with tetraplegia using a brain-computer interface (BCI)-controlled neuroprosthetic. Design: Phase I trial for an intracortical BCI integrated with forearm functional electrical stimulation (FES). Data reported span postimplant days 137 to 1478. Setting: Tertiary care outpatient rehabilitation center. Participant: A 27-year-old man with C5 class A (on the American Spinal Injury Association Impairment Scale) traumatic spinal cord injury Interventions: After array implantation in his left (dominant) motor cortex, the participant trained with BCI-FES to control dynamic, coordinated forearm, wrist, and hand movements. Main Outcome Measures: Performance on standardized tests of arm motor ability (Graded Redefined Assessment of Strength, Sensibility, and Prehension [GRASSP], Action Research Arm Test [ARAT], Grasp and Release Test [GRT], Box and Block Test), grip myometry, and functional activity measures (Capabilities of Upper Extremity Test [CUE-T], Quadriplegia Index of Function-Short Form [QIF-SF], Spinal Cord Independence Measure–Self-Report [SCIM-SR]) with and without the BCI-FES. Results: With BCI-FES, scores improved from baseline on the following: Grip force (2.9 kg); ARAT cup, cylinders, ball, bar, and blocks; GRT can, fork, peg, weight, and tape; GRASSP strength and prehension (unscrewing lids, pouring from a bottle, transferring pegs); and CUE-T wrist and hand skills. QIF-SF and SCIM-SR eating, grooming, and toileting activities were expected to improve with home use of BCI-FES. Pincer grips and mobility were unaffected. BCI-FES grip skills enabled the participant to play an adapted “Battleship” game and manipulate household objects. Conclusions: Using BCI-FES, the participant performed skillful and coordinated grasps and made clinically significant gains in tests of upper limb function. Practice generalized from training objects to household items and leisure activities. Motor ability improved for palmar, lateral, and tip-to-tip grips. The expects eventual home use to confer greater independence for activities of daily living, consistent with observed neurologic level gains from C5-6 to C7-T1. This marks a critical translational step toward clinical viability for BCI neuroprosthetics

    Preference for art: similarity, statistics, and selling price

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    ABSTRACT Factors governing human preference for artwork have long been studied but there remain many holes in our understanding. Bearing in mind contextual factors (both the conditions under which the art is viewed, and the state of knowledge viewers have regarding art) that play some role in preference, we assess in this paper three questions. First, what is the relationship between perceived similarity and preference for different types of art? Second, are we naturally drawn to certain qualities-and perhaps to certain image statistics-in art? And third, do social and economic forces tend to select preferred stimuli, or are these forces governed by non-aesthetic factors such as age, rarity, or artist notoriety? To address the first question, we tested the notion that perceived similarity predicts preference for three classes of paintings: landscape, portrait/still-life, and abstract works. We find that preference is significantly correlated with (a) the first principal component of similarity in abstract works; and (b) the second principal component for landscapes. However, portrait/still-life images did not show a significant correlation between similarity and preference, perhaps due to effects related to face perception. The preference data were then compared to a wide variety of image statistics relevant to early visual system coding. For landscapes and abstract works, nonlinear spatial and intensity statistics relevant to visual processing explained surprisingly large portions of the variance of preference. For abstract works, a quarter of the variance of preference rankings could be explained by a statistic gauging pixel sparseness. For landscape paintings, spatial frequency amplitude spectrum statistics explained one fifth of the variance of preference data. Consistent with results for similarity, image statistics for portrait/still-life works did not correlate significantly with preference. Finally, we addressed the role of value. If there are shared "rules" of preference, one might expect "free markets" to value art in proportion to its aesthetic appeal, at least to some extent. To assess the role of value, a further test of preference was performed on a separate set of paintings recently sold at auction. Results showed that the selling price of these works showed no correlation with preference, while basic statistics were significantly correlated with preference. We conclude that selling price, which could be seen as a proxy for a painting's "value," is not predictive of preference, while shared preferences may to some extent be predictable based on image statistics. We also suggest that contextual and semantic factors play an important role in preference given that image content appears to lead to greater divergence between similarity and preference ratings for representational works, and especially for artwork that prominently depicts faces. The present paper paves the way for a more complete understanding of the relationship between shared human preferences and image statistical regularities, and it outlines the basic geometry of perceptual spaces for artwork

    Genome-Wide Analyses for Osteosarcoma in Leonberger Dogs Reveal the CDKN2A/B Gene Locus as a Major Risk Locus

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    Dogs represent a unique spontaneous cancer model. Osteosarcoma (OSA) is the most common primary bone tumor in dogs (OMIA 001441-9615), and strongly resembles human forms of OSA. Several large- to giant-sized dog breeds, including the Leonberger, have a greatly increased risk of developing OSA. We performed genome-wide association analysis with high-density imputed SNP genotype data from 273 Leonberger cases with a median age of 8.1 [3.1–13.5] years and 365 controls older than eight years. This analysis revealed significant associations at the CDKN2A/B gene locus on canine chromosome 11, mirroring previous findings in other dog breeds, such as the greyhound, that also show an elevated risk for OSA. Heritability (h2SNP) was determined to be 20.6% (SE = 0.08; p-value = 5.7 × 10−4) based on a breed prevalence of 20%. The 2563 SNPs across the genome accounted for nearly all the h2SNP of OSA, with 2183 SNPs of small effect, 316 SNPs of moderate effect, and 64 SNPs of large effect. As with many other cancers it is likely that regulatory, non-coding variants underlie the increased risk for cancer development. Our findings confirm a complex genetic basis of OSA, moderate heritability, and the crucial role of the CDKN2A/B locus leading to strong cancer predisposition in dogs. It will ultimately be interesting to study and compare the known genetic loci associated with canine OSA in human OSA

    A Characterization of Brain-Computer Interface Performance Trade-Offs Using Support Vector Machines and Deep Neural Networks to Decode Movement Intent

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    Laboratory demonstrations of brain-computer interface (BCI) systems show promise for reducing disability associated with paralysis by directly linking neural activity to the control of assistive devices. Surveys of potential users have revealed several key BCI performance criteria for clinical translation of such a system. Of these criteria, high accuracy, short response latencies, and multi-functionality are three key characteristics directly impacted by the neural decoding component of the BCI system, the algorithm that translates neural activity into control signals. Building a decoder that simultaneously addresses these three criteria is complicated because optimizing for one criterion may lead to undesirable changes in the other criteria. Unfortunately, there has been little work to date to quantify how decoder design simultaneously affects these performance characteristics. Here, we systematically explore the trade-off between accuracy, response latency, and multi-functionality for discrete movement classification using two different decoding strategies–a support vector machine (SVM) classifier which represents the current state-of-the-art for discrete movement classification in laboratory demonstrations and a proposed deep neural network (DNN) framework. We utilized historical intracortical recordings from a human tetraplegic study participant, who imagined performing several different hand and finger movements. For both decoders, we found that response time increases (i.e., slower reaction) and accuracy decreases as the number of functions increases. However, we also found that both the increase of response times and the decline in accuracy with additional functions is less for the DNN than the SVM. We also show that data preprocessing steps can affect the performance characteristics of the two decoders in drastically different ways. Finally, we evaluated the performance of our tetraplegic participant using the DNN decoder in real-time to control functional electrical stimulation (FES) of his paralyzed forearm. We compared his performance to that of able-bodied participants performing the same task, establishing a quantitative target for ideal BCI-FES performance on this task. Cumulatively, these results help quantify BCI decoder performance characteristics relevant to potential users and the complex interactions between them

    Effects of low power laser irradiation on bone healing in animals: a meta-analysis

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    <p>Abstract</p> <p>Purpose</p> <p>The meta-analysis was performed to identify animal research defining the effects of low power laser irradiation on biomechanical indicators of bone regeneration and the impact of dosage.</p> <p>Methods</p> <p>We searched five electronic databases (MEDLINE, EMBASE, PubMed, CINAHL, and Cochrane Database of Randomised Clinical Trials) for studies in the area of laser and bone healing published from 1966 to October 2008. Included studies had to investigate fracture healing in any animal model, using any type of low power laser irradiation, and use at least one quantitative biomechanical measures of bone strength. There were 880 abstracts related to the laser irradiation and bone issues (healing, surgery and assessment). Five studies met our inclusion criteria and were critically appraised by two raters independently using a structured tool designed for rating the quality of animal research studies. After full text review, two articles were deemed ineligible for meta-analysis because of the type of injury method and biomechanical variables used, leaving three studies for meta-analysis. Maximum bone tolerance force before the point of fracture during the biomechanical test, 4 weeks after bone deficiency was our main biomechanical bone properties for the Meta analysis.</p> <p>Results</p> <p>Studies indicate that low power laser irradiation can enhance biomechanical properties of bone during fracture healing in animal models. Maximum bone tolerance was statistically improved following low level laser irradiation (average random effect size 0.726, 95% CI 0.08 - 1.37, p 0.028). While conclusions are limited by the low number of studies, there is concordance across limited evidence that laser improves the strength of bone tissue during the healing process in animal models.</p

    Systemic treatment with pulsed electromagnetic fields do not affect bone microarchitecture in osteoporotic rats

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    Purpose: Pulsed electromagnetic fields (PEMF) are currently used in the treatment of spinal fusions and non-unions. There are indications that PEMF might also be effective in the treatment of osteoporosis. In this study we examined whether whole-body PEMF treatment affects the bone microarchitecture in an osteoporotic rat model. Methods: Twenty-week-old female rats were ovariectomised (n020). Four different PEMF treatment protocols based on previous experimental studies and based on clinically used PEMF signals were examined (2 h/day, 5 days/week). A control group did not receive PEMF. At zero, three and six weeks cancellous and cortical bone architectural changes at the proximal tibia were evaluated using in vivo microCT scanning. Results: PEMF treatment did not induce any changes in cancellous or cortical bone compared to untreated controls. Conclusions: Although previous studies have shown strong effects of PEMF in osteoporosis we were unable to demonstrate this in any of the treatment protocols. Using in vivo microCT scanning we were able to identify small bone changes in time. Subtle differences in the experimental setup might explain the differences in study outcomes in the literature. Since PEMF treatment is safe, future experimental studies on the effect of PEMF on bone can better be performed directly on humans, eliminating the potential translation issues between animals and humans. In this study we found no support for the use of PEMF in the treatment of osteoporosis
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