1,469 research outputs found

    Axial Spondyloarthritis: Mimics and Pitfalls of Imaging Assessment

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    Axial spondyloarthritis (axSpA) is a chronic inflammatory disorder that predominantly involves the axial skeleton. Imaging findings of axSpA can be divided into active changes, which include bone marrow edema, synovitis, enthesitis, capsulitis, and intra-articular effusion, and structural changes, which include erosions, sclerosis, bone fatty infiltration, fat deposition in an erosion cavity, and bone bridging or ankylosis. The ability to distinguish between imaging lesions suggestive of axSpA and artifacts or lesions suggestive of other disorders is critical for the accurate diagnosis of axSpA. Diagnosis may be challenging, particularly in early-stage disease and magnetic resonance imaging (MRI) plays a key role in the detection of subtle or inflammatory changes. MRI also allows the detection of structural changes in the subchondral bone marrow that are not visible on conventional radiography and is of prognostic and monitoring value. However, bone structural changes are more accurately depicted using computed tomography. Conventional radiography, on the other hand, has limitations, but it is easily accessible and may provide insight on gross changes as well as rule out other pathological features of the axial skeleton. This review outlines the imaging evaluation of axSpA with a focus on imaging mimics and potential pitfalls when assessing the axial skeleton.info:eu-repo/semantics/publishedVersio

    Advances in FAI Imaging: a Focused Review

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    Purpose of review: Femoroacetabular impingement (FAI) is one of the main causes of hip pain in young adults and poses clinical challenges which have placed it at the forefront of imaging and orthopedics. Diagnostic hip imaging has dramatically changed in the past years, with the arrival of new imaging techniques and the development of magnetic resonance imaging (MRI). This article reviews the current state-of-the-art clinical routine of individuals with suspected FAI, limitations, and future directions that show promise in the field of musculoskeletal research and are likely to reshape hip imaging in the coming years. Recent findings: The largely unknown natural disease course, especially in hips with FAI syndrome and those with asymptomatic abnormal morphologies, continues to be a problem as far as diagnosis, treatment, and prognosis are concerned. There has been a paradigm shift in recent years from bone and soft tissue morphological analysis towards the tentative development of quantitative approaches, biochemical cartilage evaluation, dynamic assessment techniques and, finally, integration of artificial intelligence (AI)/deep learning systems. Imaging, AI, and hip preserving care will continue to evolve with new problems and greater challenges. The increasing number of analytic parameters describing the hip joint, as well as new sophisticated MRI and imaging analysis, have carried practitioners beyond simplistic classifications. Reliable evidence-based guidelines, beyond differentiation into pure instability or impingement, are paramount to refine the diagnostic algorithm and define treatment indications and prognosis. Nevertheless, the boundaries of morphological, functional, and AI-aided hip assessment are gradually being pushed to new frontiers as the role of musculoskeletal imaging is rapidly evolving.info:eu-repo/semantics/publishedVersio

    Investigations of fast neutron production by 190 GeV/c muon interactions on different targets

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    The production of fast neutrons (1 MeV - 1 GeV) in high energy muon-nucleus interactions is poorly understood, yet it is fundamental to the understanding of the background in many underground experiments. The aim of the present experiment (CERN NA55) was to measure spallation neutrons produced by 190 GeV/c muons scattering on carbon, copper and lead targets. We have investigated the energy spectrum and angular distribution of spallation neutrons, and we report the result of our measurement of the neutron production differential cross section.Comment: 19 pages, 11 figures ep

    Allergic contact dermatitis to shoes induced by dimethylfumarate: A new allergen imported from China

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    BACKGROUND: In the last two years several cases of severe contact dermatitis related to newly acquired sofas and armchairs originating from China have been published. The responsible allergen is dimethylfumarate (DMF), an extremely potent sensitizer and irritant found in sachets inside the furniture. Recently, cases of contact dermatitis related to shoes and riding helmets have also been described. METHODS: We evaluated two patients with allergic contact dermatitis related to shoes manufactured in China that were contaminated by dimethylfumarate found in sachets placed inside the shoeboxes. RESULTS: Patch tests with DMF extracted from the sachets inside the shoeboxes showed positive reactions. Postitive reactions were also obtained using small fragments of the shoes and tissue of the "MouldProof" sachet. The patients were instructed to avoid the suspected shoes and were treated with topical corticosteroids. CONCLUSIONS: Contact dermatitis induced by dimethylfumarate should be suspected in appropriate cases. It is important to remember that this allergen is not included in most series for patch testing

    Cam deformity and the omega angle, a novel quantitative measurement of femoral head-neck morphology: a 3D CT gender analysis in asymptomatic subjects

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    OBJECTIVE: Our objectives were to use 3D computed tomography (CT) to define head-neck morphologic gender-specific and normative parameters in asymptomatic individuals and use the omega angle (Ω°) to provide quantification data on the location and radial extension of a cam deformity. METHODS: We prospectively included 350 individuals and evaluated 188 asymptomatic hips that underwent semiautomated CT analysis. Different thresholds of alpha angle (α°) were considered in order to analyze cam morphology and determine Ω°. We calculated overall and gender-specific parameters for imaging signs of cam morphology (Ω° and circumferential α°). RESULTS: The 95 % reference interval limits were beyond abnormal thresholds found in the literature for cam morphology. Specifically, α° at 3/1 o´clock were 46.9°/60.8° overall, 51.8°/65.4° for men and 45.7°/55.3° for women. Cam prevalence, magnitude, location, and epicenter were significantly gender different. Increasing α° correlated with higher Ω°, meaning that higher angles correspond to larger cam deformities. CONCLUSION: Hip morphometry measurements in this cohort of asymptomatic individuals extended beyond current thresholds used for the clinical diagnosis of cam deformity, and α° was found to vary both by gender and measurement location. These results suggest that α° measurement is insufficient for the diagnosis of cam deformity. Enhanced morphometric evaluation, including 3D imaging and Ω°, may enable a more accurate diagnosis. KEY POINTS: • 95% reference interval limits of cam morphotype were beyond currently defined thresholds. • Current morphometric definitions for cam-type morphotype should be applied with care. • Cam prevalence, magnitude, location, and epicenter are significantly gender different. • Cam and alpha angle thresholds should be defined according to sex/location. • Quantitative 3D morphometric assessment allows thorough and reproducible FAI diagnosis and monitoring.info:eu-repo/semantics/publishedVersio

    Towards more humane machines: creating emotional social robots

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    Robots are now widely used in industrial settings, and today the world has woken up to the impact that they will have in our society. But robots have been limited to repetitive, industrial tasks. However, recent platforms are becoming more secure to operate amongst humans, and research in Human-Robot Interaction (HRI) is preparing robots for use in schools, public services and eventually everyone’s home. If we aim for a robot flexible enough to work around humans and decide autonomously how to act in complex situations, a notion of morality is needed for their decision making. In this chapter we argue that we can achieve some level of moral decision making in social robots if they are endowed with empathy capabilities. We then discuss how to build artificial empathy in robots, giving some concrete examples of how these implementations can guide the path to creating moral social robots in the future.info:eu-repo/semantics/acceptedVersio

    Controle integrado das espécies invasoras assa-peixe e casadinha em pastagens cultivadas de Paragominas, Nordeste Paraense.

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    Controle integrado de plantas invasoras em pastagens cultivadas no municĂ­pio de Terra Alta, Nordeste paraense.

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