Search results for "Biomedical engineering"
showing 10 items of 2020 documents
Continuous Glucose Monitoring in Type 1 Diabetes
2016
Background: Continuous glucose monitoring (CGM) patient systems have been shown to improve diabetes self-treatment when used consistently. The meaningful integration of this technology into everyday life, however, can vary greatly among CGM users and not all people with diabetes use CGM to its full potential. To address this issue, the study pursued 2 aims: first, to identify patient characteristics that underlie the acceptance of CGM in people with type 1 diabetes and, second, to examine the effects of different levels of experience with CGM use. Methods: Guided by a model based on the technology acceptance model (TAM), structural equation modeling (SEM) was employed to model the patient c…
Getting Physically Active by E-Bike : An Active Commuting Intervention Study
2020
Introduction: Increased physical activity (PA) is a major component in promoting public health, and active commuting could make an important contribution. Using an electric bicycle (e-bike) is reported to be of at least moderate intensity PA and is an alternative to other modes of transport for commuting. We aimed to explore the experience of commuting by e-bike in an intervention study. Methods: Focus group interviews with 21 previously inactive participants from three cities in Norway, who were given access to an e-bike for commuting for three (N = 2) or eight months (N = 19). Participants cycled for 226 days on average. The interviews were analyzed using systematic text condensation. Res…
The assessment of gingivitis using remote photoplethysmography
2020
Gum disease caused by bacterial infection, systemic conditions or neurogenic inflammation remains a prevalent and important concern of public health in both, developing and developed countries, potentially causing tooth loss if left untreated. Therefore, a simple, cost-effective, and contactless diagnostic tool is needed in dentistry. The present study aims to develop and investigate the feasibility of a motion artefact-free, miniature imaging photoplethysmography system which is dedicated for assessment of gingivitis in the dental office. The device comprised of a sub-miniature monochromatic camera equipped with miniature lens, 4-LED ring illuminator, cross polarizers and bandpass optical …
Hybrid Organic-Inorganic Nanostructures Fabricated from Layer-by-Layer Self-Assembled Multilayers of Hyperbranched Polyglycerols and Phosphorus Dendr…
2007
Multilayer thin films of cationic phosphorous dendrimers and anionic hyperbranched polyglycerols were fabricated by electrostatic layer-by-layer (LbL) self-assembly (SA). The film formation was monitored by surface plasmon resonance (SPR) spectroscopy and UV-visible spectroscopy, and it was found that the stepwise, alternating deposition results in a linear growth up to four bilayers. Hybrid organic-TiO2 nanostructures were generated by exposing the supramolecular multilayers to TiCl4 precursors. The amounts of TiO2 incorporated inside the scaffolds could be tuned by controlling the porosity of the multilayers with the addition of a small amount of salts. The resulting hybrid films exhibit …
New biodegradable hydrogels based on an acryloylated polyaspartamide cross-linked by gamma irradiation
1999
Alpha, beta-poly(N-2-hydroxyethyl)-DL-aspartamide (PHEA), a synthetic biocompatible macromolecule, was functionalized with glycidyl methacrylate (GMA) in order to introduce in its side chains residues having double bonds and ester groups. The copolymer (PHG), obtained from PHEA and GMA, had a degree of derivatization of 29 mol%. PHG aqueous solutions are cross-linked by gamma radiation at 0 degrees C either in the presence or absence of N,N'-methylenebisacrylamide (BIS) giving rise to new hydrogel systems. In both cases gelation occurs at quite low doses (0.26 and 0.4 kGy, respectively). The obtained networks were characterized by FT-IR spectrophotometry which confirmed that the cross-linki…
Biodegradable hydrogels obtained by photocrosslinking of dextran and polyaspartamide derivatives
2003
The functionalization of dextran with glycidyl methacrylate (GMA) leads to the formation of a derivative that generates hydrogels for irradiation at 365nm. The effects of various polymer concentrations and irradiation times on the yield and the properties of the obtained hydrogels are reported. The networks have been characterized by FT-IR spectra, dimensional analysis and swelling measurements carried out at different pH values. In vitro studies suggest that all samples undergo a partial chemical hydrolysis, whereas the incubation with dextranases causes a total degradation whose rate depends on the degree of crosslinking. In addition, aqueous solutions of functionalized dextran have been …
A study of reproducibility of kinesiology tape applications: review, reliability and validity
2017
Abstract Background Literature addressing the mechanical properties of kinesiology tape is quite scarce. There are no studies which focus on the mechanical characteristics of kinesiology tape, its mechanical properties, nor its adherence following the ISO international standard test methods for tape elongation. Methods This study quantified the mechanical characteristics of 380 samples of kinesiology tape from 19 different brands and in 4 different colors using a dynamometer. Mechanical testing was controlled by UNE EN ISO 13934-1. Results Significant differences were found between tape brands in terms of grammage, maximum force tenacity, work, pre-elongation and percentage elongation (P < …
Granger causality analysis of sleep brain-heart interactions
2014
We studied the networks of Granger causality (GC) between the time series of cardiac vagal autonomic activity and brain wave activities, measured respectively as the normalized high frequency (HF) component of heart rate variability and EEG power in the δ, θ, α, Ï, β bands, computed in 10 healthy subjects during sleep. GC analysis was performed by vector autoregressive modeling, and significance of each link in the network was assessed using F-statistics. The whole-night analysis revealed the existence of a fully connected network of brain-heart and brain-brain interactions, with the à EEG power acting as a hub which conveys the largest number of GC links between the heart and brain n…
Enhancement of Gene Expression by Somatic Hybridization with Primary Cells: High-Level Synthesis of the Hepatitis B Surface Antigen in Monkey Vero Ce…
1990
Vero cells transfected with the S gene encoding the surface antigen (HBsAg) of the hepatitis B virus (HBV) synthesize HBsAg at low levels. We have obtained a large increase in S gene expression by somatic hybridization of Vero cells with primary hepatocytes, which are the natural target cells for HBV infection. Fusion with cells other than hepatocytes did not enhance expression of the S gene. The Vero/hepatocyte hybrid clones analyzed are stable and have maintained a high level of HBsAg synthesis over prolonged periods. Hybrid cell lines may be of general interest for the high-level synthesis of proteins using cloned genes.
Reliability of automated optical determination of capillary refill time
2021
The present study is devoted to assessment of automated optical capillary refill time determination by custom developed optoelectronic device prototype. Study comprised fifteen healthy volunteers; To induce capillary refill time changes the hand position challenge was utilized. During rest conditions slight inter-subject variation was observed: T90 (0.75±0.27 s), TSTB (2.20±0.58 s) and temperature at the measurement site (32.21±1.87 Co), however during hand position challenge results were more consistent. Rising hand substantially increased, while lowering slightly decreased capillary refill time. We conclude that automated determination of refill time have high clinical potential, however …