Recently, numerous research works in retinal-structure analysis have been performed to analyze retinal images for diagnosing and preventing ocular diseases such as diabetic retinopathy, which is the first most common causes of vision loss in the world. In this paper, an algorithm for vessel detection in fundus images is employed. First, a denoising process using the noise-estimation-based anisotropic diffusion technique is applied to restore connected vessel lines in a retinal image and eliminate noisy lines. Next, a multi-scale line-tracking algorithm is implemented to detect all the blood

A novel procedure for the circuit implementation of the driving-point impedance of frequency-domain material models, constructed from fractional-order elements of arbitrary type and order, is introduced in this work. Following this newly introduced concept, instead of emulating separately each fractional-order element in the model under consideration, the direct emulation of the complete model can be achieved through the approximation of the total impedance function. The magnitude and phase frequency responses of the impedance function are first extracted and approximated through curve-fitting

Plasmonic photovoltaics (PVs) are promising structures that improve thin-film photovoltaics performance, where optical absorption is improved via embedding metallic nanoparticles in the PV's active layer to trap the incident optical wave into the photovoltaic cell. The presented work investigates the design of PV with both structures of conical and cylindrical metallic nanoparticles through studying their extinction cross-sections and electric field distributions. Also, the impact of these nanoparticles in silicon PVs on the optical absorption enhancement is investigated. The figure of merit

Background: One of the major concerns in implantable optoelectronics is the heat generated by emitters such as light emitting diodes (LEDs). Such devices typically produce more heat than light, whereas medical regulations state that the surface temperature change of medical implants must stay below + 2 °C. The LED's reverse current can be employed as a temperature-sensitive parameter to measure the temperature change at the implant's surface, and thus, monitor temperature rises. The main challenge in this approach is to bias the LED with a robust voltage since the reverse current is strongly

An implementation of a fractional-order differentiator-lowpass filter is presented in this work, which is constructed from Operational Transconductance Amplifiers as active cells. This offers the benefits of electronic tuning and, also, of monolithic implementation. The presented scheme has been employed for the extraction of the R peaks in electrocardiogram signals due to its efficiency for performing this task even in a noisy environment. The provided post-layout simulation results confirm the correct operation of this solution as well as its reasonable sensitivity characteristics. © 2019

Pulsed wave Doppler ultrasound is commonly used in the diagnosis of cardiovascular and blood flow abnormalities. Doppler techniques have gained clinical significance due to its safety, real-time performance and affordability. This work presents the development of a pulsed wave spectral Doppler module, which was integrated into a reconfigurable ultrasound system. The targeted system adopts a hardware-software partitioning scheme where an FPGA handles the front-end and a PC performs the back-end. Two factors were considered during the design. First, the data transfer rate between hardware and

This paper presents a comparative study of four fractional order filters used for edge detection. The noise performance of these filters is analyzed upon the addition of random Gaussian noise, as well as the addition of salt and pepper noise. The peak signal to noise ratio (PSNR) of the detected images is numerically compared. The mean square error (MSE) of the detected images as well as the execution time are also adopted as evaluation methods for comparison. The visual comparison of the filters capability in medical image edge detection is presented, that can help in the diagnosis of

This paper presents a complete analysis of the mathematical model of the gene regulation process. The model describes the induced gene expression under the effect of activators. The model differential equations are solved analytically, and the exact solution of the gene model is introduced. Moreover, a study of the model dynamics, including the fixed points and stability conditions are presented. The parameters effects on the phase plane portraits and the transient responses of the mRNA as well as the protein concentrations are intensively detailed. This work serves as a brick stone towards a

Energy harvesting was and still an important point of research. Batteries have been utilized for a long time, but they are now not compatible with the downsizing of technology. Also, their need to be recharged and changed periodically is not very desirable, therefore over the years energy harvesting from the environment and the human body have been investigated. Three energy harvesting methods which are the Piezoelectric energy harvesters, the Enzymatic Biofuel cells, and Triboelectric nanogenerators (TENGs) are being discussed in the paper. Although Biofuel cells have been investigated for a

Visualization of genome comparison data is valuable for identifying genomic structural variations and determining evolutionary events. Although there are many software tools with varying degrees of sophistication for displaying such comparisons, there is no tool for displaying dot plots of multiple genome comparisons. The dot plot mode of visualization is more appropriate and convenient than the traditional linear mode, particularly for detecting large scale genome deletions, duplications, and rearrangements. In this paper, we present VisCHAINER, which addresses this limitation, and displays