The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In this paper, we demonstrate dynamic analysis of mental sweating for sound stimulus of a few tens of eccrine sweat glands by the time-sequential piled-up en face optical coherence tomography (OCT) images with the frame spacing of 3.3 sec. In the experiment, the amount of excess sweat can be evaluated simultaneously for a few tens of sweat glands by piling up of all the en face OCT images. Non-uniformity...
Predicting location of fracture in human bones has been a keen area of research for the past few decades. A variety of tests for hardness, deformation and strain field measurement have been conducted in the past; but considered insufficient due to various limitations. Researchers therefore have proposed further studies due to inaccuracies in measurement methods, testing machines and experimental errors...
Predicting location of fracture in animal and human bones has been a keen area of research for the past few decades. It has been established that it is various types of stress that results into bone failure. Past studies were mostly based on experimental testing of variety of bones with limited accuracy equipment leading to experimental errors. An effort has been made in present research to use latest...
This paper presents a co-rotational concept for large-deflection formulation of cardiac catheters. Using this approach, the catheter is first discretized with a number of equal length beam elements and nodes, and the rigid body motions of an individual beam element are separated from its deformations. Therefore, it is adequate for modelling arbitrarily large deflections of a catheter with linear elastic...
The skin response to high radio frequency has been associated with the human physical condition and most prominently with the stress. The objective of this study is to investigate the possibility to detect mental and light physical stress through the measurement of skin reflectance in the mm-wave/sub-THz band. Two frequency bands have been considered, 75–110 GHz (Band-I) and 325–500 GHz (Band-II),...
The demand for measurements of mental stress and fatigue, which leads to low efficacy, illness, and sometimes tragic accidents, is rising up in recent years. However, detection and quantification of change in one's wakefulness which trigger mental stress and fatigue remains to be elucidated. In this paper, we focus on physiological signals showing up on one's eyelid to detect change in one's wakefulness...
In this paper, we describe how we used a smartphone app to collect migraine data. The users log their migraine details in the app with the purpose of discovering their migraine triggers. We analyze details of over half a million migraines and we report some novel findings that traditional studies missed because of their rigid clinical setting. We report the most common triggers, symptoms, relief methods,...
The cartilage surface geometry of natural human hip joint is commonly regarded as sphere. It has been widely applied in computational simulation and hip joint prosthesis design. Some new geometry models have been developed and the sphere assumption has been questioned recently. The objective of this study was to analyze joint geometry effects on cartilage contact stress distribution and investigate...
Novel carbon/salt adhesive (CSA) electrodes have been found suitable for collecting electrodermal activity (EDA) signals. Ag/AgCl electrodes are considered the standard for collecting EDA signals, because it highly avoids electrodes' polarization. Ag is an expensive commodity. Furthermore, a hydrogel layer is needed for the Ag/AgCl electrodes to collect EDA signals. Adding hydrogel to the electrodes...
Firefighting is a stressful occupation. The monitoring of psychophysiological measures in those professionals can be a way to prevent and early detect cardiac diseases and other stress-related problems. The current study aimed to assess morphological changes in the ECG signal induced by acute stress. A laboratory protocol was conducted among 6 firefighters, including a laboratory stress-inducer task...
Stress testing is used to measure the performance of the heart in an elevated stress state, in order to monitor or diagnose certain heart problems. Many measurements can be used to determine the performance of the heart, with the Tei index being the measurement of interest in this work. The Tei index has been used as a reliable method to evaluate systolic and diastolic performance, as it overcomes...
For neural probes to be used chronically for years in the human body, they must provoke minimal scarring. Recently, a number of groups have reported substantially reduced scar tissue using cellular scale electrodes below 15 μm in size. This size scale is accessible to manufacturing techniques, but can be very difficult to insert in the brain for most common electrode materials. In this study, we explore...
In this work stress is assessed based on EEG features. We focus our efforts on the correlation between subjective ratings and cerebral indices during virtual navigation scenarios. Ten male paraplegic subjects took part in the experiment and navigated in a virtual indoor environment. They had to fulfill two missions where time pressure parameter is introduced. Subjects were equipped with Electroencephalography...
Pressure and shear stress are the factors of diabetic foot ulcers and callus formation. However, in-shoe shear stress of callus measurement could not have been measured because of technical difficulties. The purpose of this study is to verify reliability and validity of the established measurement system for in-shoe pressure and shear stress. For reliability, coefficients of variation (CV) and intraclass...
Computational models were developed in the ACT-R neurocognitive architecture to address some aspects of the dynamics of behavior change. The simulations aim to address the day-to-day goal achievement data available from mobile health systems. The models refine current psychological theories of self-efficacy, intended effort, and habit formation, and provide an account for the mechanisms by which goal...
Robust electroactuators that are lightweight, power-efficient and capable of generating high forces at a low actuation voltage are of great demand in the design of micro-electromechanical systems (MEMS) for biomedical applications. In this work, electroactive composite films of alginate hydrogel and polypyrrole/polyethylene glycol (PPy/PEG) are synthesized and characterized as actuators for driving...
Simple in-shoe sensors based on film-type sensor materials were developed in this study. Three sensor materials were tested: polyvinylidenefluoride (PVDF), cellulose nanofibrils (CNF) and ElectroMechanical Film (EMFi). Plantar pressure distributions of a subject were measured with the developed in-shoe sensors; each consisting of three sensor channels (lateral and medial metatarsal heads and heel)...
Orthodontic force simulation is very important for the guidance of clinical orthodontic treatment. Previous works were mainly conducted by directly loading the force on a single or a few teeth. However, in clinic, the orthodontic force is provided by loading orthodontic appliances, and there currently is no appropriate way to measure the force on the teeth provided by the loaded appliances. This study...
The human body offers a template for many state-of-the-art prosthetic devices and sensors. In this work, we present a novel, sensorized synthetic skin that mimics the natural multi-layered nature of mechanoreceptors found in healthy glabrous skin to provide tactile information. The multi-layered sensor is made up of flexible piezoresistive textiles that act as force sensitive resistors (FSRs) to convey...
We numerically studied blood flows in a simulated branching pipe of coronary artery bifurcation, which is affected by stent implantation. We found that stent struts provide effects as guide vanes and blockages on the flow into circumflex branch. The former effect increases the flow rate and shear stress on the arteriosclerosis-prone site. The blockage effect may overwhelm the guide effect depending...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.