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A current-mode system to self-measure temperature on implantable optoelectronics
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
Design of fractional-order differentiator-lowpass filters for extracting the R peaks in ECG signals
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
Simple implementations of fractional-order driving-point impedances: Application to biological tissue models
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
Biohybrid soft robots, E-skin, and bioimpedance potential to build up their applications: A review
Soft Robotics is a new approach towards better human-robot interaction and biomimicry in the robotics field. Its integration with biological materials (Biohybrid soft robotics) is one of the topics being focused on in the soft robotics research in the last fifteen years. The motive for this approach is to combine the best of biological and artificial systems. In this article, Biohybrid soft robots and Electronic Skin (E-skin), which is considered one of the advances of soft robotics, are reviewed. Their most significant milestones and the highlights of their most researched applications are
Mathematical analysis of gene regulation activator model
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
Evaluation of Different Sudan Dyes in Egyptian Food Samples Utilizing Liquid Chromatography/Tandem Mass Spectrometry
A sensitive and a precise method was developed for the quantification of different Sudan dyes in some Egyptian food samples. They were analyzed utilizing two-fragment ion transition under multiple reaction monitoring (MRM) mode. Separation was carried out on Kinetex 2.6u C18 100 A (75 mm × 4.6 mm) phenomenex using isocratic elution with 10:90% water and acetonitrile containing 2.0 mmol/L ammonium formate and 0.2% formic acid. The validation parameters were obtained and verified. The linearity was 0.2–10.0 ng/mL with r2 > 0.9975. LOD and LOQ were 0.06 and 0.19 ng/mL, respectively, for Sudan (I
Cold flow numerical simulation inside local pottery furnace for different designs for the air inlet
One of the many pleasures of living in Egypt is having the opportunity to visit places like a village called Tunis in El-Fayoum governorate which is a touristic village and export art and handicraft such as Pottery for 3-4 decades. The clay processing in the traditional pottery industry contains several stages. The process and quality of the pottery have to be improved to reduce pollution and the manufacturing round time which could be done through improving the heating process. Towards this goal, turbulent three-dimensional numerical simulations for the in-use air inlet and a modified design
Cole bio-impedance model variations in daucus carota sativus under heating and freezing conditions
This paper reports on the variations in the parameters of the single dispersion Cole bio-impedance model of Daucus Carota Sativus (carrots) under heating and freezing conditions. Experiments are conducted on six samples with recorded live bio-impedance spectra versus temperature. The Cole model parameters are extracted from the measured data using the Flower Pollination Algorithm (FPA) optimization technique and their variations are correlated with well-known bio-chemical and bio-mechanical variations. This represents a non-invasive method for characterizing and measuring the degree of change
Chitosan and EDTA conjugated graphene oxide antinematodes in Eggplant: Toward improving plant immune response
A new strategy regarding the fabrication of chitosan (CS) or ethylene diamine tetraacetic acid (EDTA) on graphene oxide (GO) was performed. The nematocidal potential against Meloidogyne incognita causing root-knot infection in eggplant was tested. The plant immune response was investigated through measuring the photosynthetic pigments, phenols and proline contents, oxidative stress, and antioxidant enzymes activity. Results indicating that, the treatment by pure GO recorded the most mortality percentages of M. incognita 2nd juveniles followed by GO-CS then GO-EDTA. In vivo greenhouse
J-aggregates of amphiphilic cyanine dyes for dye-sensitized solar cells: A combination between computational chemistry and experimental device physics
We report on the design and structure principles of 5,5′-6,6′-tetrachloro-1,1′-dioctyl-3,3′-bis-(3-carboxypropyl)-benzimidacarbocyanine (Dye 1). Such metal-free amphiphilic cyanine dyes have many applications in dye-sensitized solar cells. AFM surface topographic investigation of amphiphilic molecules of Dye 1 adsorbed on TiO2 anode reveals the ability of spontaneous self-organization into highly ordered aggregates of fiber-like structure. These aggregates are known to exhibit outstanding optical properties of J-aggregates, namely, efficient exciton coupling and fast exciton energy migration
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