Recovering the superficial microvascular pattern via diffuse reflection imaging: phantom validation

Background: Diffuse reflection imaging could potentially be used to recover the superficial microvasculature under cutaneous tissue and the associated blood oxygenation status with a modified imaging resolution. The aim of this work is to deliver a new approach of local off-axis scanning diffuse reflection imaging, with the revisit of the modified Beer–Lambert Law (MBLL). Methods: To validate this, the system is used to recover the micron-scale subsurface vessel structure interiorly embedded in a skin equivalent tissue phantom. This vessel structure is perfused with oxygenated meta-hemoglobin solution. Results: Our preliminary results confirm that the thin vessel structure can be mapped into a 2-D planar image. The distributions of oxygenated hemoglobin concentration (CtHbO2) and deoxygenated hemoglobin concentration (CtRHb) can be co-registerated through the MBLL upon the CW spectroscopy, the scattering issue is addressed in the reformed MBLL. The recovered pattern matches to the estimation from the simultaneous optical coherence tomography studies. Conclusions: With further modification, this system may serve as the first prototype to investigate the superficial microvasculature in the expotential skin cancer loci, or a micro-lesion of vascular dermatosis

Sleep and cognitive performance:cross-sectional associations from the UK Biobank

Objective: The relationship between insomnia symptoms and cognitive performance is unclear, particularly at the population level. We conducted the largest examination of this association to date through analysis of the UK Biobank, a large population-based sample of adults aged 40-69 yrs. We also sought to determine associations between cognitive performance and self-reported chronotype, sleep medication use, and sleep duration. Methods: This cross-sectional, population-based study involved 477,529 participants, comprising 133,314 with frequent insomnia symptoms (age: 57.4 ± 7.7 yrs; 62.1% female) and 344,215 controls without (age: 56.1 ± 8.2 yrs; 52.0% female). Cognitive performance was assessed through a touchscreen test battery probing reasoning, basic reaction time, numeric memory, visual memory and prospective memory. Adjusted models included relevant demographic, clinical and sleep variables. Results: Frequent insomnia symptoms were associated with cognitive impairment in unadjusted models, however these effects were reversed after full adjustment, leaving those with frequent insomnia symptoms showing statistically better cognitive performance over those without. Relative to intermediate chronotype, evening chronotype was associated with superior task performance, while morning chronotype was associated with the poorest performance. Sleep medication use and both long (>9hrs) and short (<7hrs) sleep duration were associated with impaired performance. Conclusions: Our results suggest that after adjustment for potential confounding variables, frequent insomnia symptoms may be associated with a small statistical advantage, which is unlikely to be clinically meaningful, on simple neurocognitive tasks. Further work is required to examine mechanistic underpinnings of an apparent evening chronotype advantage in cognitive performance, as well as impairment associated with morning chronotype, sleep medication use, and sleep duration extremes

In-Situ Occlusion Resolution for Hybrid Tabletop Environments

International audienceIn this paper we explore the use of in situ occlusion resolution in mixed physical/digital tabletop scenarios. We propose the extension of back-projected tabletops with interactive top-projection to turn the physical object’s surface into peripheral displays. These displays are used to resolve occlusion in situ without the need to use additional tabletop display space and keeping the spatial perception of the occluded objects. We contribute a visualization concept and a set of interaction techniques for in situ occlusion resolution and easy access to occluded objects. The techniques are implemented in a system named ProjecTop, which is evaluated in an quantitative user study. The study results highlight how top-projection can be beneficially used. We conclude with a set of design implications derived from the study’s results

PeriTop: Extending Back-Projected Tabletops with Top-Projected Peripheral Displays

Integrating digital tabletops into homes or desktop environments will give rise to a set of problems emerging from placing everyday objects on interactive tabletops. Chief among them is the arbitrary placement of physical objects that considerably limits the digital working space on the surface of tabletops. In this paper we contribute PeriTop, an interactive back-projected tabletop system which exploit the surface of physical objects and tabletop rims as additional interactive displays to represent and interact with digital objects. This is realized by augmenting the tabletop system with an inexpensive pico projector-depth camera pair. We support the PeriTop approach by depicting several salient use case scenarios aiding users in performing activities on hybrid physical-digital tabletop settings

StackTop: Hybrid Physical-Digital Stacking on Interactive Tabletops

The concurrent use of digital and physical documents on interactive surfaces is becoming more and more common. However, the integration of both document types is limited, one example being the ability to stack documents. In this paper we propose StackTop, an integrated system supporting ordered hybrid digital/physical piling (hybrid stacking) on interactive surfaces. This allows for a tighter physical/digital integration in hybrid workspaces and provides a more consistant approach when working with hybrid document sets

In-Situ Occlusion Resolution for Hybrid Tabletop Environments

International audienceIn this paper we explore the use of in situ occlusion resolution in mixed physical/digital tabletop scenarios. We propose the extension of back-projected tabletops with interactive top-projection to turn the physical object’s surface into peripheral displays. These displays are used to resolve occlusion in situ without the need to use additional tabletop display space and keeping the spatial perception of the occluded objects. We contribute a visualization concept and a set of interaction techniques for in situ occlusion resolution and easy access to occluded objects. The techniques are implemented in a system named ProjecTop, which is evaluated in an quantitative user study. The study results highlight how top-projection can be beneficially used. We conclude with a set of design implications derived from the study’s results

FlowPut: Environment-Aware Interactivity for Tangible 3D Objects

Tangible interaction has shown to be beneficial in a wide variety of scenarios since it provides more direct manipulation and haptic feedback. Further, inherently three-dimensional information is represented more naturally by a 3D object than by a flat picture on a screen. Yet, today's tangibles have often pre-defined form factors and limited input and output facilities. To overcome this issue, the combination of projection and depth cameras is used as a fast and flexible way of non-intrusively adding input and output to tangibles. However, tangibles are often quite small and hence the space for output and interaction on their surface is limited. Therefore, we propose FlowPut: an environment-aware framework that utilizes the space available on and around a tangible object for projected visual output. By means of an optimization-based layout approach, FlowPut considers the environment of the objects to avoid interference between projection and real-world objects. Moreover, we contribute an occlusion resilient object recognition and tracking for tangible objects based on their 3D model and a point-cloud based multi-touch detection, that allows sensing touches also on the side of a tangible. Flowput is validated through a series of technical experiments, a user study, and two example applications.</jats:p