Advances in human-computer interactions: methods, algorithms, and applications

Editoria

Near-optimal combination of disparity across a log-polar scaled visual field

The human visual system is foveated: we can see fine spatial details in central vision, whereas resolution is poor in our peripheral visual field, and this loss of resolution follows an approximately logarithmic decrease. Additionally, our brain organizes visual input in polar coordinates. Therefore, the image projection occurring between retina and primary visual cortex can be mathematically described by the log-polar transform. Here, we test and model how this space-variant visual processing affects how we process binocular disparity, a key component of human depth perception. We observe that the fovea preferentially processes disparities at fine spatial scales, whereas the visual periphery is tuned for coarse spatial scales, in line with the naturally occurring distributions of depths and disparities in the real-world. We further show that the visual system integrates disparity information across the visual field, in a near-optimal fashion. We develop a foveated, log-polar model that mimics the processing of depth information in primary visual cortex and that can process disparity directly in the cortical domain representation. This model takes real images as input and recreates the observed topography of human disparity sensitivity. Our findings support the notion that our foveated, binocular visual system has been moulded by the statistics of our visual environment

Early Lance-Adams syndrome after cardiac arrest: Prevalence, time to return to awareness, and outcome in a large cohort.

Early myoclonus after cardiac arrest (CA) is traditionally viewed as a poor prognostic sign (status myoclonus). However, some patients may present early Lance-Adams syndrome (LAS): under appropriate treatment, they can reach a satisfactory functional outcome. Our aim was to describe their profile, focusing on pharmacologic management in the ICU, time to return of awareness, and long-term prognosis. Adults with early LAS (defined as generalized myoclonus within 96h, with epileptiform EEG within 48h after CA) were retrospectively identified in our CA registry between 2006 and 2016. Functional outcome was assessed through cerebral performance categories (CPC) at 3 months, CPC 1-2 defined good outcome. Among 458 consecutive patients, 7 (1.5%) developed early LAS (4 women, median age 59 years). Within 72h after CA, in normothemia and off sedation, all showed preserved brainstem reflexes and localized pain. All patients were initially treated with valproate, levetiracetam and clonazepam; additional agents, including propofol and midazolam, were prescribed in the majority. First signs of awareness occurred after 3-23 days (median 11.8); 3/7 reached a good outcome at 3 months. Early after CA, myoclonus together with a reactive, epileptiform EEG, preserved evoked potentials and brainstem reflexes suggests LAS. This condition was managed with a combination of highly dosed, large spectrum antiepileptic agents including propofol and midazolam. Even if awakening was at times delayed, good outcome occurred in a substantial proportion of patients

Geometric View of Measurement Errors

The slope of the best fit line from minimizing the sum of the squared oblique errors is the root of a polynomial of degree four. This geometric view of measurement errors is used to give insight into the performance of various slope estimators for the measurement error model including an adjusted fourth moment estimator introduced by Gillard and Iles (2005) to remove the jump discontinuity in the estimator of Copas (1972). The polynomial of degree four is associated with a minimun deviation estimator. A simulation study compares these estimators showing improvement in bias and mean squared error

Chromosomal control of non-gliadin proteins from the 70% ethanol extract of wheat endosperm

The non-gliadin fraction of the 70% ethanol extracts of compensated nulli-tetrasomics and ditelosomics of Triticum aestivum cv. Chinese Spring has been analyzed by combined electrofocusing and electrophoresis. Seventeen of the 21 protein map components of the euploid have been ascribed to eight chromosomes: 4A, 3BS, 6BS, 7BS, 3D, 4D, 5D and 7DS. The relationship of the different map components with other proteins previously associated with the same chromosomes is discusse

Method of Collective Degrees of Freedom in Spin Coherent State Path Integral

We present a detailed field theoretic description of those collective degrees of freedom (CDF) which are relevant to study macroscopic quantum dynamics of a quasi-one-dimensional ferromagnetic domain wall. We apply spin coherent state path integral (SCSPI) in the proper discrete time formalism (a) to extract the relevant CDF's, namely, the center position and the chirality of the domain wall, which originate from the translation and the rotation invariances of the system in question, and (b) to derive effective action for the CDF's by elimination of environmental zero-modes with the help of the {\it Faddeev-Popov technique}. The resulting effective action turns out to be such that both the center position and the chirality can be formally described by boson coherent state path integral. However, this is only formal; there is a subtle departure from the latter.Comment: 10 pages, 1 figur