Fractional‐order mutual inductance: analysis and design

This paper introduces for the first time the generalized concept of the mutual inductance in the fractional‐order domain where the symmetrical and unsymmetrical behaviors of the fractional‐order mutual inductance are studied. To use the fractional mutual inductance in circuit design and simulation, an equivalent circuit is presented with its different conditions of operation. Also, simulations for the impedance matrix parameters of the fractional mutual inductance equivalent circuit using Advanced Design System and MATLAB are illustrated. The Advanced Design System and MATLAB simulations of the double‐tuned filter based on the fractional mutual inductance are discussed. A great matching between the numerical analysis and the circuit simulation appears, which confirms the reliability of the concept of the fractional mutual inductance. Also, the analysis of the impedance matching using the fractional‐order mutual inductance is introduced. Copyright © 2015 John Wiley & Sons, Ltd.     

Observing single cell NF-κB dynamics under stimulant concentration gradient

Study of cell signaling often requires examination of the cellular dynamics under variation in the stimulant concentration. Such variation has typically been conducted by dispensing cell populations in a number of chambers or wells containing discrete concentrations. Such practice adds to the complexity associated with experimental or device design and requires substantial labor for implementation. Furthermore, there is also potential risk of missing important results due to the often arbitrary selection of discrete concentration values for testing. In this Letter, we study NF-κB activation and translocation at the single cell level using a microfluidic device that generates continuously varying concentration gradient. We use only three device settings to cover stimulant (interleukin-1β) concentrations of 4 orders of magnitude (0.001-10 ng/mL). Such device allows us to study temporal dynamics of NF-κB in single cells under different stimulant concentrations by real-time imaging. Interestingly, our results reveal that, while the percent of cells with NF-κB translocation decreases with lower stimulant concentration in the range of 0.1-0.001 ng/mL, the response time of such translocation remains constant, reflected by the single cell data.     

Application Tests of New Wetting Compositions for Wildland Firefighting

Extinguishing forest fires is a critical issue for fire brigades; fire can spread throughout vast areas in a relatively short period of time. The studies presented in this paper describe the results of laboratory and field tests of new compositions of wetting agents for extinguishing wildland fires. The studies assessed the ability to penetrate surface fuels using 0.5 and 1% solution of wetting compositions. The penetration of the liquid through the layer of the loose rotting wood with solutions of obtained wetting agents was up to 68 times faster than with water. The absorption of water droplet was even 40 times slower in comparison to wetting agent solutions. Based on laboratory research, compositions that exhibit the best wetting properties were analysed in real conditions in field tests to assess their capacity to penetrate in surface fuels, their ability to make fire barriers and their efficiency in suppressing fires of soil cover and thickets. In tests performed in 4 m² plots, the wetting compositions hold the flames from crossing a thin firebreak for up to three times longer periods than water. The results of the studies confirmed a significant increase in efficiency when new biodegradable wetting agents are employed to extinguish forest fires.     

Fully digital jerk-based chaotic oscillators for high throughput pseudo-random number generators up to 8.77 Gbits/s

This paper introduces fully digital implementations of four different systems in the 3rd order jerk-equation based chaotic family using the Euler approximation. The digitization approach enables controllable chaotic systems that reliably provide sinusoidal or chaotic output based on a selection input. New systems are introduced, derived using logical and arithmetic operations between two system implementations of different bus widths, with up to 100× higher maximum Lyapunov exponent than the original jerk-equation based chaotic systems. The resulting chaotic output is shown to pass the NIST SP. 800-22 statistical test suite for pseudo-random number generators without post-processing by only eliminating the statistically defective bits. The systems are designed in Verilog HDL and experimentally verified on a Xilinx Virtex 4 FPGA for a maximum throughput of 15.59 Gbits/s for the native chaotic output and 8.77 Gbits/s for the resulting pseudo-random number generators.     

Low-energy He-ion beam modifications the surface properties of biomaterial

In the present work, ultra-high-molecular-weight polyethylene (UHMWPE) films were irradiated with 130 keV He ions. The fluence of the ion beam was ranged from 1 × 10¹² to 1 × 10¹⁶ cm^?2. The chemical, morphological, and crystallite structure changes resulted from the ion bombardment were obtained using different spectroscopic techniques. These techniques were Fourier transform infrared spectrometer, scanning electron microscope, X-ray diffraction, and UV–vis spectrophotometry. The surface free energy for untreated and ion-beam-treated samples was determined by means of contact angle measurements of three different liquids. Our results showed a decrease in the crystallinity of UHMWPE and formation of C=O groups on the polymer surface for modified samples as well. A remarkable shifting in the UV–vis spectra toward lower energy and increase in the optical absorption were observed as the ion fluence increases. Measurements of the contact angle indicate remarkable increase in the surface free energy as a function of ion fluence.     

Performance of current controllers for VSI-fed IPMSM drive

The current-controlled voltage-source-inverter-fed interior permanent-magnet synchronous motor (IPMSM) has received widespread interest in high-precision industrial drive applications. This paper presents a detailed comparison of various current controller schemes, particularly hysteresis and ramp comparator controllers for the IPMSM drive based on performance at different speeds. The hysteresis and the ramp comparator controllers are getting more attention due to their simplicity and high dynamic responses. In this paper, fixed, sinusoidal, and mixed-band hysteresis current controllers, as well as conventional ramp and improved ramp comparator controllers, are considered. The harmonic spectra of the motor line currents for various current controllers are obtained using a fast Fourier transform for comparison purposes. The comparison is based on experimental results. In order to compare the performance of various controllers, the complete drive system is implemented in real time using the digital signal processor controller board DS-1102.     

Selective Recovery of Cadmium,Cobalt, and Nickel from Spent Ni–Cd Batteries Using Adogen® 464 and Mesoporous Silica Derivatives

Spent Ni–Cd batteries are now considered an important source for many valuable metals. The recovery of cadmium, cobalt, and nickel from spent Ni–Cd Batteries has been performed in this study. The optimum leaching process was achieved using 20% H₂SO₄, solid/liquid (S/L) 1/5 at 80 °C for 6 h. The leaching efficiency of Fe, Cd, and Co was nearly 100%, whereas the leaching efficiency of Ni was 95%. The recovery of the concerned elements was attained using successive different separation techniques. Cd(II) ions were extracted by a solvent, namely, Adogen^® 464, and precipitated as CdS with 0.5% Na₂S solution at pH of 1.25 and room temperature. The extraction process corresponded to pseudo-2nd-order. The prepared PTU-MS silica was applied for adsorption of Co(II) ions from aqueous solution, while the desorption process was performed using 0.3 M H₂SO₄. Cobalt was precipitated at pH 9.0 as Co(OH)₂ using NH₄OH. The kinetic and thermodynamic parameters were also investigated. Nickel was directly precipitated at pH 8.25 using a 10% NaOH solution at ambient temperature. FTIR, SEM, and EDX confirm the structure of the products.     

ERAP/HLA-C and KIR Genetic Profile in Couples with Recurrent Implantation Failure

Proper embryo implantation depends on the tolerance of the maternal immune system to the fetus and its foreign paternal antigens. During implantation and early pregnancy, the dominant leukocytes in the uterus are uterine NK cells, expressing killer immunoglobulin-like receptors (KIR). KIRs recognize human leukocyte antigens (HLA-C) on the human trophoblast inherited from the father and mother. The antigenic peptides presented by the HLA are formed via their cleavage by endoplasmic reticulum aminopeptidases ERAP1 and ERAP2. The aim of this study was to assess the association of combined KIR genes and their HLA-C ligands, as well as ERAP1 and ERAP2 polymorphisms with recurrent implantation failure after in vitro fertilization (RIF). We tested 491 couples who underwent in vitro fertilization (IVF) and 322 fertile couples. Genotype CC rs27044 ERAP1 in female with a male’s HLA-C1C1 or HLA-C1C2 protected from RIF (p/p_corr. = 0.005/0.044, OR = 0.343; p/p_corr. = 0.003/0.027, OR = 0.442, respectively). Genotype TT rs30187 ERAP1 in female with a male’s HLA-C1C2 genotype increased the risk of RIF. Summarizing, in the combination of female ERAP1 and an HLA-C partner, the rs30187 C>T and rs27044 C>G polymorphisms play an important role in implantation failure.     

Anticoagulants as Potential SARS-CoV-2 Mpro Inhibitors for COVID-19 Patients: In Vitro,Molecular Docking,Molecular Dynamics,DFT, and SAR Studies

In this article, 34 anticoagulant drugs were screened in silico against the main protease (M^pro) of SARS-CoV-2 using molecular docking tools. Idraparinux, fondaparinux, eptifibatide, heparin, and ticagrelor demonstrated the highest binding affinities towards SARS-CoV-2 M^pro. A molecular dynamics study at 200 ns was also carried out for the most promising anticoagulants to provide insights into the dynamic and thermodynamic properties of promising compounds. Moreover, a quantum mechanical study was also conducted which helped us to attest to some of the molecular docking and dynamics findings. A biological evaluation (in vitro) of the most promising compounds was also performed by carrying out the MTT cytotoxicity assay and the crystal violet assay in order to assess inhibitory concentration 50 (IC₅₀). It is worth noting that ticagrelor displayed the highest intrinsic potential for the inhibition of SARS-CoV-2 with an IC₅₀ value of 5.60 µM and a safety index of 25.33. In addition, fondaparinux sodium and dabigatran showed promising inhibitory activities with IC₅₀ values of 8.60 and 9.40 µM, respectively, and demonstrated safety indexes of 17.60 and 15.10, respectively. Moreover, the inhibitory potential of the SARS-CoV-2 M^pro enzyme was investigated by utilizing the SARS-CoV-2 M^pro assay and using tipranavir as a reference standard. Interestingly, promising SARS-CoV-2 M^pro inhibitory potential was attained for fondaparinux sodium with an IC₅₀ value of 2.36 µM, surpassing the reference tipranavir (IC₅₀ = 7.38 µM) by more than three-fold. Furthermore, highly eligible SARS-CoV-2 M^pro inhibitory potential was attained for dabigatran with an IC₅₀ value of 10.59 µM. Finally, an SAR was discussed, counting on the findings of both in vitro and in silico approaches.     

Electrical conduction in some (CnH2n) (NH 3 + )2 FeCl4 compounds

The d.c. conductivity, a.c. conductivity and thermoelectric power of the compounds H₃N₊(CH₂)₊ NH₃FeCl₄, wheren=2, 3, 7 and 10, have been studied over a temperature range of 150–500 K. The conductivity results confirm the presence of more than one structural phase transition for each compound investigated. The thermoelectric power measurements showed that electrons are the main charge carriers in all crystal phases. The conductivity results were explained on the basis of an electron hopping mechanism over the whole temperature range.