Comparison of polynomial and rational function cornea models for effective dimensionality reduction.

This study aims to examine geometric models of the corneal surface that can be used to reduce in reasonable time the dimensionality of datasets of normal anterior corneas. Polynomial models (P) like Zernike polynomials (ZP) and spherical harmonic polynomials (SHP) were obvious candidates along with their rational function (R) counterparts, namely Zernike rational functions (ZR) and spherical harmonic rational functions (SHR, new model). Knowing that both SHP and ZR were more accurate than ZP for the modeling of normal and keratoconus corneas, it was expected that both spherical harmonic (SH) models (SHP and SHR) would be more accurate than their Zernike (Z) counterparts (ZP and ZR, respectively), and both rational (R) models (SHR and ZR) more accurate than their polynomial counterparts (SHP and ZP, respectively) for a low dimensional space (coefficient number J < 30).

Skeleton Graph-Neural-Network-Based Human Action Recognition: A Survey.

Human action recognition has been applied in many fields, such as video surveillance and human computer interaction, where it helps to improve performance. Numerous reviews of the literature have been done, but rarely have these reviews concentrated on skeleton-graph-based approaches. Connecting the skeleton joints as in the physical appearance can naturally generate a graph.

SmithNet: Strictness on Motion-Texture Coherence for Anomaly Detection.

Anomaly detection is a key functionality in various vision systems, such as surveillance and security. In this work, we present a convolutional neural network (CNN) that supports the detection of anomaly, which has not been defined when building the model, at frame level. Our CNN, named SmithNet, is structured to simultaneously learn commonly occurring textures and their corresponding motion.

Perceptions and needs regarding technologies in nursing homes: An exploratory study.

Two of the most salient problems in nursing homes are the responsive behaviours and falls of older people living with Alzheimer's disease and related disorders. Intelligent videomonitoring and mobile applications are potential technologies that may help prevent and manage these problems. However, evidence for the needs for technologies in nursing homes is scarce.

The effects of a strong desire to void on gait for incontinent and continent older community-dwelling women at risk of falls.

Aims: The fall rate in urgency urinary incontinence (UUI) and mixed UI (MUI) older women is higher when compared with that of continent women. One hypothesis is that a strong desire to void (SDV) could alter gait parameters and therefore increase the risk of falls. The aim of this study was to investigate and compare the effect of SDV on gait parameters in UUI/MUI and continent older women who experienced falls.

Conditions and ethical challenges that could influence the implementation of technologies in nursing homes: A qualitative study.

Aim: To explore the conditions that may influence the implementation of an interactive mobile application (app) and an intelligent videomonitoring system (IVS) in nursing homes (NHs) and the ethical challenges of their use.

Background: There is a lack of knowledge about implementing technologies in NHs and the ethical challenges that might arise. In past studies, nursing care teams expressed the need for technologies offering clinical support.

Measurement of Human Gait Symmetry using Body Surface Normals Extracted from Depth Maps.

In this paper, we introduce an approach for measuring human gait symmetry where the input is a sequence of depth maps of subject walking on a treadmill. Body surface normals are used to describe 3D information of the walking subject in each frame. Two different schemes for embedding the temporal factor into a symmetry index are proposed.

Automatic IVUS lumen segmentation using a 3D adaptive helix model.

In this paper, we develop a three dimensional (3D) segmentation algorithm of the lumen visualized using intravascular ultrasound (IVUS) imaging. These images are known for their various granular textures (speckles) that make the discrimination of different tissues very difficult, especially as a result of the presence of artifacts and shadows generated by tissue calcification. Our model consists of a helical active contour initialized automatically over the sequence, that evolves based on the analysis of the Rayleigh distribution of gray levels in order to extract the luminal border.

Human gait symmetry assessment using a depth camera and mirrors.

It is proposed in this paper a reliable approach for human gait symmetry assessment using a Time-of-Flight (ToF) depth camera and two mirrors. The setup formed from these devices provides a sequence of 3D point clouds that is the input of our system. A cylindrical histogram is estimated for describing the posture in each point cloud.

Skeleton-Based Abnormal Gait Detection.

Human gait analysis plays an important role in musculoskeletal disorder diagnosis. Detecting anomalies in human walking, such as shuffling gait, stiff leg or unsteady gait, can be difficult if the prior knowledge of such a gait pattern is not available. We propose an approach for detecting abnormal human gait based on a normal gait model.

3D Corneal Shape After Implantation of a Biosynthetic Corneal Stromal Substitute.

Purpose: The current and projected shortage of transplantable human donor corneas has prompted the development of long-term alternatives to human donor tissue for corneal replacement. The biosynthetic stromal substitutes (BSS) characterized herein represent a potentially safe alternative to donor organ transplantation for anterior corneal stromal diseases. The goal of this phase 1 safety study was to characterize the three-dimensional (3D) corneal shape of the first 10 human patients implanted with a BSS and assess its stability over time.

[Intelligent videosurveillance and falls detection: Perceptions of professionals and managers].

Description: Gerontechnologies can be used to detect accidental falls. However, existing systems do not entirely meet users' expectations. Our team developed an intelligent video-monitoring systems to fill these gaps.

Perception et réceptivité des proches-aidants à l'égard de la vidéosurveillance intelligente pour la détection des chutes des aînés à domicile.

To address the issue of falls, which are increasing as the population ages, an intelligent video-monitoring system is being developed. The aim of the study is to explore caregivers' perceptions of and receptiveness to a prototype of this fall detection system. A cross-sectional mixed-method study was carried out with individual interviews of 18 caregivers.

A perceptual map for gait symmetry quantification and pathology detection.

Background: The gait movement is an essential process of the human activity and the result of collaborative interactions between the neurological, articular and musculoskeletal systems, working efficiently together. This explains why gait analysis is important and increasingly used nowadays for the diagnosis of many different types (neurological, muscular, orthopedic, etc.) of diseases.

Corneal Shape, Volume, and Interocular Symmetry: Parameters to Optimize the Design of Biosynthetic Corneal Substitutes.

Purpose: To characterize the three-dimensional (3D) shape, volume distribution, and mirror symmetry of the right and left corneas at the scale of a large population, based on the integrated analysis of 3D corneal shape average maps and topography parameters.

Methods: A total of 7670 Orbscan II corneal topographies from 3835 consenting subjects with no history of ocular disease were studied. Average topography maps were created using the right and left corneal topographies of all subjects.

New lower-limb gait asymmetry indices based on a depth camera.

Background: Various asymmetry indices have been proposed to compare the spatiotemporal, kinematic and kinetic parameters of lower limbs during the gait cycle. However, these indices rely on gait measurement systems that are costly and generally require manual examination, calibration procedures and the precise placement of sensors/markers on the body of the patient.

Methods: To overcome these issues, this paper proposes a new asymmetry index, which uses an inexpensive, easy-to-use and markerless depth camera (Microsoft Kinect™) output.

A new registration algorithm for estimating and discriminating average shapes of sets of corneal topographies.

In this study we present a method to build 3D corneal atlases of different populations using a registration step based on inter-surface volume minimization. First the construction method is presented. It is based on a global factor computation in order to minimize the volume between several surfaces.

Evaluating perceptual maps of asymmetries for gait symmetry quantification and pathology detection.

The gait movement is a complex and essential process of the human activity. Yet, many types of diseases (neurological, muscular, orthopedic, etc.) can be diagnosed from the gait analysis.

Detection of gait cycles in treadmill walking using a Kinect.

Treadmill walking is commonly used to analyze several gait cycles in a limited space. Depth cameras, such as the low-cost and easy-to-use Kinect sensor, look promising for gait analysis on a treadmill for routine outpatient clinics. However, gait analysis is based on accurately detecting gait events (such as heel-strike) by tracking the feet which may be incorrectly recognized with Kinect.

Multilevel mediation: cumulative contextual risk, maternal differential treatment, and children's behavior within families.

This study tests the hypothesis that links between contextual risk and children's outcomes are partially explained by differential parenting. Using multi-informant measurement and including up to four children per family (Mage  = 3.51, SD = 2.

Lower limb movement asymmetry measurement with a depth camera.

The gait movement seems simple at first glance, but in reality it is a very complex neural and biomechanical process. In particular, if a person is affected by a disease or an injury, the gait may be modified. The left-right asymmetry of this movement can be related to neurological diseases, segment length differences or joint deficiencies.

Methodology for the construction and comparison of 3D models of the human cornea.

This paper describes a methodology to build and compare 3D models (or atlases) of the cornea for specific populations. Using topography data of the anterior and posterior corneal surfaces, average and statistical variation maps are computed after registration of individual corneas on a reference sphere. With this methodology, a normal population model is constructed and compared with known eye anatomic data.

Analyzing gait pathologies using a depth camera.

In this paper, we present a new approach to construct a 3D human skeleton model, which is then used to quantify gait pathologies, using a depth camera. First, thanks to the depth map, we obtain a human depth silhouette in 3D, from which our method is based to estimate each body part position. Second, the angle between the upper and lower legs of the 3D skeleton model is calculated.