2,451 research outputs found

    Pixel classification for automated diabetic foot diagnosis

    Get PDF
    Worldwide, more than 180 million people suffer from diabetes mellitus. Approximately 50% of these patients will develop complications to their feet. Neuropathy, combined with poor blood supply and biomechanical changes results in a high risk for foot ulcers, which is a key problem in the diabetic foot; when these wounds become infected, this can ultimately result in lower extremity amputation, which has a serious effect on the quality of life of the patient, and causes a large economic burden on society.\ud \ud This was the motivation for a collaborate project (Vincent50) in which a photographic foot imaging device was developed. The system allows scanning of the foot soles on a daily basis which may lead to early recognition of foot problems. The goal of the present study is to determine whether pixel classification is a useful intermediate step towards automatically assessing the images of the foot soles for signs of diabetic foot disease. If successful, this approach will further relief health care professionals in assessing the foot and enable the placement of more devices in the future. \ud \ud The best agreement between automated recognition and expert diagnosis was achieved with a combination of RGB and derived features, proves that the RGB data is informative with respect to detection of ulcers. However, the automatic detection of pre-signs of ulcers and other anomalies needs more sophistication than pixel classification alone. Firstly, other physical features, such as hyperspectral data, infrared and/or textural features are expected to be more informative. Secondly, we expect to be able to boost the performance by using the context between neighboring pixels. Thirdly, an individualized and normalized classification process might help with the large variability in foot soles between individuals. \u

    Angular dependence of domain wall resistivity in SrRuO3_{{\bf 3}} films

    Full text link
    SrRuO3{\rm SrRuO_3} is a 4d itinerant ferromagnet (Tc_{c} ∌\sim 150 K) with stripe domain structure. Using high-quality thin films of SrRuO3_{3} we study the resistivity induced by its very narrow (∌3\sim 3 nm) Bloch domain walls, ρDW\rho_{DW} (DWR), at temperatures between 2 K and Tc_{c} as a function of the angle, Ξ\theta , between the electric current and the ferromagnetic domains walls. We find that ρDW(T,Ξ)=sin⁥2ΞρDW(T,90)+B(Ξ)ρDW(T,0)\rho_{DW}(T,\theta)=\sin^2\theta \rho_{DW}(T,90)+B(\theta)\rho_{DW}(T,0) which provides the first experimental indication that the angular dependence of spin accumulation contribution to DWR is sin⁥2Ξ\sin^2\theta. We expect magnetic multilayers to exhibit a similar behavior.Comment: 5 pages, 5 figure

    The Energetics of Li Off-Centering in K1−x_{1-x}Lix_xTaO3_3; First Principles Calculations

    Full text link
    K1−x_{1-x}Lix_{x}TaO3_3 (KLT) solid solutions exhibit a variety of interesting physical phenomena related to large displacements of Li-ions from ideal perovskite A-site positions. First-principles calculations for KLT supercells were used to investigate these phenomena. Lattice dynamics calculations for KLT exhibit a Li off-centering instability. The energetics of Li-displacements for isolated Li-ions and for Li-Li pairs up to 4th neighbors were calculated. Interactions between nearest neighbor Li-ions, in a Li-Li pair, strongly favor ferroelectric alignment along the pair axis. Such Li-Li pairs can be considered "seeds" for polar nanoclusters in KLT. Electrostriction, local oxygen relaxation, coupling to the KT soft-mode, and interactions with neighboring Li-ions all enhance the polarization from Li off-centering. Calculated hopping barriers for isolated Li-ions and for nearest neighbor Li-Li pairs are in good agreement with Arrhenius fits to experimental dielectric data.Comment: 14 pages including 10 figures. To Physical Review B. Replaced after corrections due to referees' remark

    Beyond "the Relationship between the Individual and Society": broadening and deepening relational thinking in group analysis

    Get PDF
    The question of ‘the relationship between the individual and society’ has troubled group analysis since its inception. This paper offers a reading of Foulkes that highlights the emergent, yet evanescent, psychosocial ontology in his writings, and argues for the development of a truly psychosocial group analysis, which moves beyond the individual/society dualism. It argues for a shift towards a language of relationality, and proposes new theoretical resources for such a move from relational sociology, relational psychoanalysis and the ‘matrixial thinking’ of Bracha Ettinger which would broaden and deepen group analytic understandings of relationality

    Infrared dermal thermography on diabetic feet soles to predict ulcerations: a case study

    Get PDF
    Diabetic foot ulceration is a major complication for patients with diabetes mellitus. If not adequately treated, these ulcers may lead to foot infection, and ultimately to lower extremity amputation, which imposes a major burden to society and great loss in health-related quality of life for patients. Early identification and subsequent preventive treatment have proven useful to limit the incidence of foot ulcers and lower extremity amputation. Thus, the development of new diagnosis tools has become an attractive option. The ultimate objective of our project is to develop an intelligent telemedicine monitoring system for frequent examination on patients’ feet, to timely detect pre-signs of ulceration. Inflammation in diabetic feet can be an early and predictive warning sign for ulceration, and temperature has been proven to be a vicarious marker for inflammation. Studies have indicated that infrared dermal thermography of foot soles can be one of the important parameters for assessing the risk of diabetic foot ulceration. This paper covers the feasibility study of using an infrared camera, FLIR SC305, in our setup, to acquire the spatial thermal distribution on the feet soles. With the obtained thermal images, automated detection through image analysis was performed to identify the abnormal increased/decreased temperature and assess the risk for ulceration. The thermography for feet soles of patients with diagnosed diabetic foot complications were acquired before the ordinary foot examinations. Assessment from clinicians and thermography were compared and follow-up measurements were performed to investigate the prediction. A preliminary case study will be presented, indicating that dermal thermography in our proposed setup can be a screening modality to timely detect pre-signs of ulceration

    Virtual reality facial emotion recognition in social environments:An eye-tracking study

    Get PDF
    BACKGROUND: Virtual reality (VR) enables the administration of realistic and dynamic stimuli within a social context for the assessment and training of emotion recognition. We tested a novel VR emotion recognition task by comparing emotion recognition across a VR, video and photo task, investigating covariates of recognition and exploring visual attention in VR. METHODS: Healthy individuals (n = 100) completed three emotion recognition tasks; a photo, video and VR task. During the VR task, emotions of virtual characters (avatars) in a VR street environment were rated, and eye-tracking was recorded in VR. RESULTS: Recognition accuracy in VR (overall 75%) was comparable to the photo and video task. However, there were some differences; disgust and happiness had lower accuracy rates in VR, and better accuracy was achieved for surprise and anger in VR compared to the video task. Participants spent more time identifying disgust, fear and sadness than surprise and happiness. In general, attention was directed longer to the eye and nose areas than the mouth. DISCUSSION: Immersive VR tasks can be used for training and assessment of emotion recognition. VR enables easily controllable avatars within environments relevant for daily life. Validated emotional expressions and tasks will be of relevance for clinical applications

    Eigenvector localization for random band matrices with power law band width

    Full text link
    It is shown that certain ensembles of random matrices with entries that vanish outside a band around the diagonal satisfy a localization condition on the resolvent which guarantees that eigenvectors have strong overlap with a vanishing fraction of standard basis vectors, provided the band width WW raised to a power ÎŒ\mu remains smaller than the matrix size NN. For a Gaussian band ensemble, with matrix elements given by i.i.d. centered Gaussians within a band of width WW, the estimate Ό≀8\mu \le 8 holds.Comment: 30 pages; corrected typo

    Interface optical phonons in spheroidal dots: Raman selection rules

    Full text link
    The contribution of interface phonons to the first order Raman scattering in nanocrystals with non spherical geometry is analyzed. Interface optical phonons in the spheroidal geometry are discussed and the corresponding Frohlich-like electron-phonon interaction is reported in the framework of the dielectric continuum approach. It is shown that the interface phonon modes are strongly dependent on the nanocrystal geometry, particularly on the ellipsoid's semi-axis ratio. The new Raman selection rules have revealed that solely interface phonon modes with even angular momentum are allowed to contribute to the first order phonon-assisted scattering of light. On this basis we are able to give an explanation for the observed low frequency shoulders present in the Raman cross-section of several II-VI semiconductor nanostructures.Comment: 8 pages, 2 figure

    How emergency managers (mis?)interpret forecasts

    Full text link
    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146849/1/disa12293.pd
    • 

    corecore