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This page shows you the most recent publications within this specialty of the MedWorm directory.

Extended Target Tracking Using Gaussian Processes
In this paper, we propose using Gaussian processes to track an extended object or group of objects, that generates multiple measurements at each scan. The shape and the kinematics of the object are simultaneously estimated, and the shape is learned online via a Gaussian process. The proposed algorithm is capable of tracking different objects with different shapes within the same surveillance region. The shape of the object is expressed analytically, with well-defined confidence intervals, which can be used for gating and association. Furthermore, we use an efficient recursive implementation of the algorithm by deriving a s...
Source: IEEE Transactions on Signal Processing - July 3, 2015 Category: Biomedical Engineering Source Type: research

Compressive Periodogram Reconstruction Using Uniform Binning
In this paper, two problems that show great similarities are examined. The first problem is the reconstruction of the angular-domain periodogram from spatial-domain signals received at different time indices. The second one is the reconstruction of the frequency-domain periodogram from time-domain signals received at different wireless sensors. We split the entire angular or frequency band into uniform bins. The bin size is set such that the received spectra at two frequencies or angles, whose distance is equal to or larger than the size of a bin, are uncorrelated. These problems in the two different domains lead to a simi...
Source: IEEE Transactions on Signal Processing - July 3, 2015 Category: Biomedical Engineering Source Type: research

A model based study of a quantitative relation between joint strengthening and the highest achievable speed of human walking
The objective of this paper is to briefly introduce this framework and present the obtained results based on that, for the mentioned relation. To achieve the objective of this paper, the highest achievable speed in sagittal plane with normal joint strength was first determined in the mathematical framework for three age groups. Afterward, the highest achievable speed was calculated for different levels of ankle, knee, and hip strength by changing the strength level in the mathematical model in all the studied groups. The results supported the crucial role of plantar flexors in all ages. It was shown that ankle strengthenin...
Source: Biocybernetics and Biomedical Engineering - July 3, 2015 Category: Biomedical Engineering Source Type: research

A new approach to robust, weighted signal averaging
Publication date: Available online 2 July 2015 Source:Biocybernetics and Biomedical Engineering Author(s): Tomasz Pander In this paper, a new approach for robust, weighted averaging of time-aligned signals is proposed. Suppression of noise in such case can be achieved with the use of the averaging technique. The signals are time-aligned and then the average template is determined. To this end, the arithmetic mean operator is often applied to the synchronized signal samples or its various modifications. However, the disadvantage of the mean operator is its sensitivity to outliers. The weighted averaging operation can be r...
Source: Biocybernetics and Biomedical Engineering - July 3, 2015 Category: Biomedical Engineering Source Type: research

An automatic aneurysm extraction algorithm in fused brain digital subtraction angiography images
Publication date: Available online 2 July 2015 Source:Biocybernetics and Biomedical Engineering Author(s): Saba Momeni , Hossein Pourghassem Brain aneurysm is one of the most life-threatening events, which is associated with a high rate of mortality and disability. There are many factors, which specify the best treatment option for each particular patient. In this paper, an automatic computer-aided extraction algorithm for brain aneurysm, from fused digital subtraction angiography (DSA) images is proposed. In this algorithm, firstly, to remove vessel structure, morphological operations based on multi-directional structur...
Source: Biocybernetics and Biomedical Engineering - July 3, 2015 Category: Biomedical Engineering Source Type: research

Verification of the pure alanine in PMMA tube dosimeter applicability for dosimetry of radiotherapy photon beams: a feasibility study
Abstract Alanine dosimeters in the form of pure alanine powder in PMMA plastic tubes were investigated for dosimetry in a clinical application. Electron paramagnetic resonance (EPR) spectroscopy was used to measure absorbed radiation doses by detection of signals from radicals generated in irradiated alanine. The measurements were performed for low-dose ranges typical for single-fraction doses often used in external photon beam radiotherapy. First, the dosimeters were irradiated in a solid water phantom to establish calibration curves in the dose range from 0.3 to 3 Gy for 6 and 18 MV X-ray beams from a clinica...
Source: Australasian Physical and Engineering Sciences in Medicine - July 3, 2015 Category: Biomedical Engineering Source Type: research

Breakdown of deterministic lateral displacement efficiency for non-dilute suspensions: A numerical study
Separation of cellular blood components is an important step in clinical diagnosis of diseases, such as malaria [1], as well as in medical research focusing on phenotype and/or genotype of the various subtypes of blood cells. The traditional blood separation methods employed for clinical tests typically involve large sample volumes and often costly specialist equipment [1]. The advent of microfluidic separation techniques for biological cells has opened up the possibility of replacement of traditional blood tests with lab-on-chip diagnostics [2,3]. (Source: Medical Engineering and Physics)
Source: Medical Engineering and Physics - July 2, 2015 Category: Biomedical Engineering Authors: R. Vernekar, T. Krüger Source Type: research

Design and testing of a high-speed treadmill to measure ground reaction forces at the limit of human gait
The use of instrumented treadmills to measure the ground reaction forces produced during the foot ground contacts of human walkers and runners has become wide spread in both clinical and scientific settings. These devices substantially enhance both the quality and quantity of kinetic data obtained from the assessment of steady-speed walking and running by reducing the variability of within stride parameters and by substantially reducing subject time commitments and the research personnel effort compared to the use of in-ground force platforms. (Source: Medical Engineering and Physics)
Source: Medical Engineering and Physics - July 2, 2015 Category: Biomedical Engineering Authors: Matthew W. Bundle, Michael O. Powell, Laurence J. Ryan Tags: Technical note Source Type: research

Fluidic system for long-term in vitro culturing and monitoring of organotypic brain slices.
Abstract Brain slice preparations cultured in vitro have long been used as a simplified model for studying brain development, electrophysiology, neurodegeneration and neuroprotection. In this paper an open fluidic system developed for improved long term culturing of organotypic brain slices is presented. The positive effect of continuous flow of growth medium, and thus stability of the glucose concentration and waste removal, is simulated and compared to the effect of stagnant medium that is most often used in tissue culturing. Furthermore, placement of the tissue slices in the developed device was studied by numer...
Source: Biomedical Microdevices - July 1, 2015 Category: Biomedical Engineering Authors: Bakmand T, Troels-Smith AR, Dimaki M, Nissen JD, Andersen KB, Sasso L, Waagepetersen HS, Gramsbergen JB, Svendsen WE Tags: Biomed Microdevices Source Type: research

Predicting Complete Ground Reaction Forces and Moments During Gait With Insole Plantar Pressure Information Using a Wavelet Neural Network
In general, three-dimensional ground reaction forces (GRFs) and ground reaction moments (GRMs) that occur during human gait are measured using a force plate, which are expensive and have spatial limitations. Therefore, we proposed a prediction model for GRFs and GRMs, which only uses plantar pressure information measured from insole pressure sensors with a wavelet neural network (WNN) and principal component analysis-mutual information (PCA-MI). For this, the prediction model estimated GRFs and GRMs with three different gait speeds (slow, normal, and fast groups) and healthy/pathological gait patterns (healthy and adolesce...
Source: Journal of Biomechanical Engineering - July 1, 2015 Category: Biomedical Engineering Source Type: research

Establishing the Framework for Fabrication of a Bioartificial Heart
There is a chronic shortage of donor hearts. The ability to fabricate complete bioartificial hearts (BAHs) may be an alternative solution. The current study describes a method to support the fabrication and culture of BAHs. Rat hearts were isolated and subjected to a detergent based decellularization protocol to remove all cellular components, leaving behind an intact extracellular matrix. Primary cardiac cells were isolated from neonatal rat hearts, and direct cell transplantation was used to populate the acellular scaffolds. Bioartificial hearts were maintained in a custom fabrication gravity fed perfusion culture system...
Source: ASAIO Journal - July 1, 2015 Category: Medical Equipment Tags: Biomedical Engineering Source Type: research

Analysis of short-term heart rate and diastolic period variability using a refined fuzzy entropy method
In this study, a refined fuzzy entropy (rFuzzyEn) was developed by substituting a piecewise fuzzy membership function for the Gaussian function in conventional fuzzy entropy (FuzzyEn) measure. Its stability and robustness against additive noise compared with sample entropy (SampEn) and FuzzyEn, were examined by two well-accepted simulation models—the 1 / f α noise and the Logistic attractor. The rFuzzyEn was further applied to evaluate clinical short-term (5 min) HRV a...
Source: BioMedical Engineering OnLine - July 1, 2015 Category: Biomedical Engineering Authors: Lizhen JiPeng LiKe LiXinpei WangChangchun Liu Source Type: research

A Pipeline for the Generation of Realistic 3D Synthetic Echocardiographic Sequences: Methodology and Open-Access Database
Quantification of cardiac deformation and strain with 3D ultrasound takes considerable research efforts. Nevertheless, a widespread use of these techniques in clinical practice is still held back due to the lack of a solid verification process to quantify and compare performance. In this context, the use of fully synthetic sequences has become an established tool for initial in silico evaluation. Nevertheless, the realism of existing simulation techniques is still too limited to represent reliable benchmarking data. Moreover, the fact that different centers typically make use of in-house developed simulation pipelines make...
Source: IEE Transactions on Medical Imaging - July 1, 2015 Category: Biomedical Engineering Source Type: research

Sum-Rate Optimal Network Beamforming and Subcarrier Power Allocation for Multi-Carrier Asynchronous Two-Way Relay Networks
In this paper, we consider a multicarrier asynchronous bidirectional relay network, where different relay-transceiver links can cause different delays in the signals they convey, thereby producing inter-symbol-interference at the two transceivers. Such a two-way relay link can be modeled as a frequency selective channel with multiple taps, and thus, it can be equalized using orthogonal frequency division multiplexing (OFDM) transmission and reception schemes at the two transceivers, while the relays use simple amplify-and-forward relaying protocol. We prove rigorously that maximizing the sum-rate under a total power budget...
Source: IEEE Transactions on Signal Processing - June 30, 2015 Category: Biomedical Engineering Source Type: research

38th Annual International Conference of the IEEE Engineering in Medicine and Biology Society
(Source: IEE Transactions on Medical Imaging)
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

IEEE Transactions on Medical Imaging information for authors
(Source: IEE Transactions on Medical Imaging)
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

Stratified Sampling Voxel Classification for Segmentation of Intraretinal and Subretinal Fluid in Longitudinal Clinical OCT Data
Automated three-dimensional retinal fluid (named symptomatic exudate-associated derangements, SEAD) segmentation in 3D OCT volumes is of high interest in the improved management of neovascular Age Related Macular Degeneration (AMD). SEAD segmentation plays an important role in the treatment of neovascular AMD, but accurate segmentation is challenging because of the large diversity of SEAD size, location, and shape. Here a novel voxel classification based approach using a layer-dependent stratified sampling strategy was developed to address the class imbalance problem in SEAD detection. The method was validated on a set of ...
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

A Unified Sparse Recovery and Inference Framework for Functional Diffuse Optical Tomography Using Random Effect Model
Diffuse optical tomography (DOT) is a non-invasive imaging technique to reconstruct optical properties of biological tissues using near-infrared light, and it has been successfully used to measure functional brain activities via changes in cerebral blood volume and cerebral blood oxygenation. However, DOT presents a severely ill-posed inverse problem, so various types of regularization should be incorporated to overcome low spatial resolution and lack of depth sensitivity. Another limitation of the conventional DOT reconstruction methods is that an inference step is separately performed after the reconstruction, so complic...
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

3D Microendoscopic Electrical Impedance Tomography for Margin Assessment During Robot-Assisted Laparoscopic Prostatectomy
Radially configured microendoscopic electrical impedance probes intended for intraoperative surgical margin assessment during robot-assisted laparoscopic prostatectomy (RALP) were examined through simulation, bench-top experimentation, and ex vivo tissue studies. Three probe designs with 8, 9, and 17 electrodes, respectively, were analyzed through finite element method based simulations. One mm diameter spherical inclusions ($sigma _{rm inclusion} =1~{rm S}/{rm m}$) are positioned at various locations within a hemispherical background ($sigma _{rm background} =0.1~{rm S}/{rm m}$) of radius 5 mm. An 8-electrode configuratio...
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

Efficient Lattice Boltzmann Solver for Patient-Specific Radiofrequency Ablation of Hepatic Tumors
Radiofrequency ablation (RFA) is an established treatment for liver cancer when resection is not possible. Yet, its optimal delivery is challenged by the presence of large blood vessels and the time-varying thermal conductivity of biological tissue. Incomplete treatment and an increased risk of recurrence are therefore common. A tool that would enable the accurate planning of RFA is hence necessary. This manuscript describes a new method to compute the extent of ablation required based on the Lattice Boltzmann Method (LBM) and patient-specific, pre-operative images. A detailed anatomical model of the liver is obtained from...
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

Spatio-Temporal Tensor Decomposition of a Polyaffine Motion Model for a Better Analysis of Pathological Left Ventricular Dynamics
Given that heart disease can cause abnormal motion dynamics over the cardiac cycle, understanding and quantifying cardiac motion can provide insight for clinicians to aid with diagnosis, therapy planning, and determining prognosis. The goal of this paper is to extract population-specific motion patterns from 3D displacements in order to identify the mean motion in a population, and to describe pathology-specific motion patterns in terms of the spatial and temporal components. Since there are common motion patterns observed in patients with the same condition, extracting these can lead towards a better understanding of the ...
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

3-D Stent Detection in Intravascular OCT Using a Bayesian Network and Graph Search
Worldwide, many hundreds of thousands of stents are implanted each year to revascularize occlusions in coronary arteries. Intravascular optical coherence tomography is an important emerging imaging technique, which has the resolution and contrast necessary to quantitatively analyze stent deployment and tissue coverage following stent implantation. Automation is needed, as current, it takes up to 16 h to manually analyze hundreds of images and thousands of stent struts from a single pullback. For automated strut detection, we used image formation physics and machine learning via a Bayesian network, and 3-D knowledge of sten...
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

Low-Dimensional Non-Rigid Image Registration Using Statistical Deformation Models From Semi-Supervised Training Data
Accurate and robust image registration is a fundamental task in medical image analysis applications, and requires non-rigid transformations with a large number of degrees of freedom. Statistical deformation models (SDMs) attempt to learn the distribution of non-rigid deformations, and can be used both to reduce the transformation dimensionality and to constrain the registration process. However, high-dimensional SDMs are difficult to train given orders of magnitude fewer training samples. In this paper, we utilize both a small set of annotated imaging data and a large set of unlabeled data to effectively learn an SDM of no...
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

Robust Low-Dose CT Perfusion Deconvolution via Tensor Total-Variation Regularization
Acute brain diseases such as acute strokes and transit ischemic attacks are the leading causes of mortality and morbidity worldwide, responsible for 9% of total death every year. “Time is brain” is a widely accepted concept in acute cerebrovascular disease treatment. Efficient and accurate computational framework for hemodynamic parameters estimation can save critical time for thrombolytic therapy. Meanwhile the high level of accumulated radiation dosage due to continuous image acquisition in CT perfusion (CTP) raised concerns on patient safety and public health. However, low-radiation leads to increased nois...
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

Resolution Guarantees in Electrical Impedance Tomography
Electrical impedance tomography (EIT) uses current-voltage measurements on the surface of an imaging subject to detect conductivity changes or anomalies. EIT is a promising new technique with great potential in medical imaging and non-destructive testing. However, in many applications, EIT suffers from inconsistent reliability due to its enormous sensitivity to modeling and measurement errors. In this work, we show that it is principally possible to give rigorous resolution guarantees in EIT even in the presence of systematic and random measurement errors. We derive a constructive criterion to decide whether a desired reso...
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

Direct Parametric Image Reconstruction in Reduced Parameter Space for Rapid Multi-Tracer PET Imaging
In this study, we developed a direct parametric image reconstruction (DPIR) method for estimating kinetic parameters and recovering single tracer information from rapid multi-tracer PET measurements. This is achieved by integrating a multi-tracer model in a reduced parameter space (RPS) into dynamic image reconstruction. This new RPS model is reformulated from an existing multi-tracer model and contains fewer parameters for kinetic fitting. Ordered-subsets expectation-maximization (OSEM) was employed to approximate log-likelihood function with respect to kinetic parameters. To incorporate the multi-tracer model, an iterati...
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

A Reconstruction-Classification Method for Multifrequency Electrical Impedance Tomography
We present a combined reconstruction-classification method for estimating the spectra of individual tissues, whilst simultaneously reconstructing the conductivity. The advantage of this method is that a priori knowledge of the spectra is not required to be exact in that the constraints are updated at each step of the reconstruction. In this paper, we investigate the robustness of the proposed method to errors in the initial guess of the tissue spectra, and look at the effect of introducing spatial smoothing. We formalize and validate a frequency-difference variant of reconstruction-classification, and compare the use of ab...
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

Spatially-Adaptive Reconstruction in Computed Tomography Using Neural Networks
We propose a supervised machine learning approach for boosting existing signal and image recovery methods and demonstrate its efficacy on example of image reconstruction in computed tomography. Our technique is based on a local nonlinear fusion of several image estimates, all obtained by applying a chosen reconstruction algorithm with different values of its control parameters. Usually such output images have different bias/variance trade-off. The fusion of the images is performed by feed-forward neural network trained on a set of known examples. Numerical experiments show an improvement in reconstruction quality relativel...
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

Microstructural Characterization of the Pia-Arachnoid Complex Using Optical Coherence Tomography
This study provides the first quantifiable data of arachnoid trabeculae and subarachnoid vasculature distribution within the PAC and will be valuable to understanding brain biomechanics during head trauma. (Source: IEE Transactions on Medical Imaging)
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

Benchmark for Algorithms Segmenting the Left Atrium From 3D CT and MRI Datasets
We present results for nine algorithms for CT and eight algorithms for MRI. Results showed that methodologies combining statistical models with region growing approaches were the most appropriate to handle the proposed task. The ground truth and automatic segmentations were standardised to reduce the influence of inconsistently defined regions (e.g., mitral plane, PVs end points, LA appendage). This standardisation framework, which is a contribution of this work, can be used to label and further analyse anatomical regions of the LA. By performing the standardisation directly on the left atrial surface, we can process multi...
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

IEEE Transactions on Medical Imaging publication information
(Source: IEE Transactions on Medical Imaging)
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

Cell Detection From Redundant Candidate Regions Under Nonoverlapping Constraints
Cell detection in microscopy images is essential for automated cell behavior analysis including cell shape analysis and cell tracking. Robust cell detection in high-density and low-contrast images is still challenging since cells often touch and partially overlap, forming a cell cluster with blurry intercellular boundaries. In such cases, current methods tend to detect multiple cells as a cluster. If the control parameters are adjusted to separate the touching cells, other problems often occur: a single cell may be segmented into several regions, and cells in low-intensity regions may not be detected. To solve these proble...
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

Derivation of an Observer Model Adapted to Irregular Signals Based on Convolution Channels
Anthropomorphic model observers are mathe- matical algorithms which are applied to images with the ultimate goal of predicting human signal detection and classification accuracy across varieties of backgrounds, image acquisitions and display conditions. A limitation of current channelized model observers is their inability to handle irregularly-shaped signals, which are common in clinical images, without a high number of directional channels. Here, we derive a new linear model observer based on convolution channels which we refer to as the “Filtered Channel observer” (FCO), as an extension of the channelized ...
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

Table of Contents
(Source: IEE Transactions on Medical Imaging)
Source: IEE Transactions on Medical Imaging - June 30, 2015 Category: Biomedical Engineering Source Type: research

Segmentation of white blood cells and comparison of cell morphology by linear and naïve Bayes classifiers
Conclusions: The proposed system, based on normal white blood cell morphology and its characteristics, was applied to two different datasets. The results of the calibrated segmentation process on both datasets are fast, robust, efficient and coherent. Meanwhile, the classification of normal white blood cells into five types shows high sensitivity in both linear and naïve Bayes models, with slightly better results in the linear classifier. (Source: BioMedical Engineering OnLine)
Source: BioMedical Engineering OnLine - June 30, 2015 Category: Biomedical Engineering Authors: Jaroonrut PrinyakuptCharnchai Pluempitiwiriyawej Source Type: research

Prediction of hip joint load and translation using musculoskeletal modelling with force-dependent kinematics and experimental validation
Musculoskeletal lower limb models are widely used to predict the resultant contact force in the hip joint as a non-invasive alternative to instrumented implants. Previous musculoskeletal models based on rigid body assumptions treated the hip joint as an ideal sphere with only three rotational degrees of freedom. An musculoskeletal model that considered force-dependent kinematics with three additional translational degrees of freedom was developed and validated in this study by comparing it with a previous experimental measurement. A 32-mm femoral head against a polyethylene cup was considered in the musculoskeletal model f...
Source: Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine - June 30, 2015 Category: Biomedical Engineering Authors: Zhang, X., Chen, Z., Wang, L., Yang, W., Li, D., Jin, Z. Tags: Original Articles Source Type: research

Evaluation of postural steadiness in below-knee amputees when wearing different prosthetic feet during various sensory conditions using the Biodex(R) Stability System
In recent years, computerized posturography has become an essential tool in quantitative assessment of postural steadiness in the clinical settings. The purpose of this study was to explore the ability of the Biodex® Stability System (BSS) to quantify postural steadiness in below-knee amputees. A convenience sample of 10 below-knee amputees participated in the study. The overall (OSI), anterior–posterior (APSI) and medial–lateral (MLSI) stability indexes as well as the percentage of time spent in left and right quadrants and four concentric zones were measured under altered sensory conditions while standing...
Source: Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine - June 30, 2015 Category: Biomedical Engineering Authors: Arifin, N., Abu Osman, N. A., Ali, S., Gholizadeh, H., Wan Abas, W. A. B. Tags: Original Articles Source Type: research

Inverse-model-based cuffless blood pressure estimation using a single photoplethysmography sensor
This paper proposes an inverse-model-based cuffless method for estimating blood pressure using a single photoplethysmography sensor. The proposed method, which is based on the relationship between blood pressure and the features of pulse waves, employs an inverse estimation and uses the blood pressure as the explanatory variable. Using this method, the blood pressure can be estimated with high accuracy even in situations where the pulse wave features are scattered, as the method uses the dynamic signal-to-noise ratio of the Taguchi method. In order to verify the effectiveness of the proposed method, we employed it to measu...
Source: Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine - June 30, 2015 Category: Biomedical Engineering Authors: Suzuki, A. Tags: Original Articles Source Type: research

Influences of dehydration and rehydration on the lubrication properties of phospholipid polymer-grafted cross-linked polyethylene
In this study, the lubrication properties of PMPC-grafted CLPE were evaluated in reciprocating friction test with rehydration process by unloading in various lubricants. The start-up friction of PMPC-grafted CLPE was reduced, and the damage of PMPC layer was suppressed by rehydration in water or hyaluronic acid solutions. In contrast, the start-up friction of PMPC-grafted CLPE increased in fetal bovine serum solution, and the damage for PMPC layer was quite noticeable. Interestingly, the start-up friction of PMPC-grafted CLPE was reduced in fetal bovine serum solution containing hyaluronic acid, and the damage of the PMPC ...
Source: Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine - June 30, 2015 Category: Biomedical Engineering Authors: Yarimitsu, S., Moro, T., Kyomoto, M., Watanabe, K., Tanaka, S., Ishihara, K., Murakami, T. Tags: Original Articles Source Type: research

Characteristics of locomotion efficiency of an expanding-extending robotic endoscope in the intestinal environment
This article describes the research on the characteristics of an expanding–extending robotic endoscope’s locomotion efficiency in real intestine and explores an approach to improve the locomotion ability in this environment. In the article, the robot’s locomotion efficiency was first calculated according to its gait in the gut, and the reasons for step losses were analyzed. Next, dynamical models of the robot and the intestine were built to calculate the step losses caused by failed anchoring and intestinal compression/extension. Based on the models and the calculation results, methods for reducing step l...
Source: Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine - June 30, 2015 Category: Biomedical Engineering Authors: He, S., Yan, G., Wang, Z., Gao, J., Yang, K. Tags: Original Articles Source Type: research

Numerical investigation of the hydrodynamic parameters of blood flow through stenotic descending aorta
In this study, the blood flow passing through a three-dimensional geometrically realistic stenosis is investigated both experimentally and numerically. Although the blood flow in stenotic arteries has been extensively studied in the past few decades, not much work has been focused on irregularity of stenosis. Thus, a model of an irregular stenotic descending aorta is used in this work. Due to the irregularity of stenosis model, the governing differential equations for continuity and momentum are solved numerically using finite-volume/finite-difference techniques in the generalized body-fitted coordinates. In order to verif...
Source: Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine - June 30, 2015 Category: Biomedical Engineering Authors: Pasha Zanous, S., Shafaghat, R., Esmaili, Q. Tags: Technical Note Source Type: research

A comparison between direct TMR measurements and TMRs calculated from PDDs using BJR Supplement 25 data for flattened and unflattened photon beams
This study assessed the validity of the conversion from percentage depth dose (PDD) to tissue maximum ratio (TMR) using BJR Supplement 25 data for flattened and flattening filter free (FFF) beams. PDD and TMR scans for a variety of field sizes were measured in water using a Sun Nuclear Corporation 3D SCANNER™ on a Varian TrueBeam linear accelerator in 6 MV, 10 MV and 6 MV FFF beams. The BJR Supplement 25 data was used to convert the measured PDDs to TMRs and these were compared with the directly measured TMR data. The TMR plots calculated from PDD were within 1 % for the 10 MV and 6 MV flattened beams, for field size...
Source: Australasian Physical and Engineering Sciences in Medicine - June 30, 2015 Category: Biomedical Engineering Source Type: research

Current Approaches and Future Trends to Promote Tendon Repair.
Abstract Tendons are composed by extracellular collagen fibres arranged in regular arrays and are responsible to transmit tensile forces from a muscle to a bone. Due to their poor healing ability, in some cases tendons injuries are debilitating impairments that affect life quality among adult population worldwide. In the last years, attending to the social and economic concern associated to the high prevalence of tendons injuries and the limited success of the available current treatments, several scaffolds have been developed. Some of these scaffolds are intended to be used as graft-augmentation devices and others...
Source: Annals of Biomedical Engineering - June 30, 2015 Category: Biomedical Engineering Authors: Morais DS, Torres J, Guedes RM, Lopes MA Tags: Ann Biomed Eng Source Type: research

Stable nonpolar solvent droplet generation using a poly(dimethylsiloxane) microfluidic channel coated with poly-p-xylylene for a nanoparticle growth.
Abstract Applications of microfluidic devices fabricated in poly(dimethylsiloxane) (PDMS) have been limited to water-based analysis rather than nonpolar solvent based chemistry due to a PDMS swelling problem that occurs by the absorption of the solvents. The absorption and swelling causes PDMS channel deformation in shape, and changes the cross sectional area making it difficult to control the flow rate and concentrations of solution in PDMS microfluidic channels. We propose that poly-p-xylylene polymers (parylenes) are chemical vapors deposited on the surfaces of PDMS channels that alleviate the effect of solvents...
Source: Biomedical Microdevices - June 27, 2015 Category: Biomedical Engineering Authors: Lim H, Moon S Tags: Biomed Microdevices Source Type: research