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Abstract An investigation into the optical and mechanical properties of a novel borate glasses with the chemical composition of 70 B2O3-10 Li2O-10ZnO-5Bi2O3-5CaO-xEu2O3 was conducted. The glassy specimens of Eu3+-doped borate were prepared by the melting-quenching technique. An enhanced density from 3.0860 to 3.2176 g cm−3 and reduced molar volume from 29.27819 to 29.17447 (cm3 mol−1) are the outcome of increasing the concentration of Eu3+ in glasses. Plotting the extinction coefficient, dielectric constant (ε1, ε2), and refractive index (n) against wavelength reveals that they all rise as level of Eu3+ elements in the glass lattice increases. An increase in Eu3+ concentration results in a decrease in both the volume (VELF) and surface (SELF) energy loss functions. Also, all elastic-mechanical moduli (such as Young’s, Bulk, Shear, and Elongation) increase with increasing the quantity of Eu3+ ions in the glass lattice. The Young’s modulus (Y, GPa) of the glassy specimens was 34.512, 36.089, 36.504, 36.730 and 37.114 GPa for x equal 0, 0.25, 0.5, 0.75 and 1 mol ratio in the glass system, and coded by Eu-0.0, Eu-0.25, Eu-0.5, Eu-0.75 and Eu-1.0, respectively. Growing Eu2O3 levels resulted in an increase in Micro-Hardness from 2.050 to 2.146 GPa. Poisson’s ratio values for Eu-0.0, Eu-0.250, Eu-0.5, Eu-0.75 and Eu-1.0 were 0.273, 0.275, 0.277, 0.277 and 0.278, respectively.

Water reuse for irrigation is a common practice globally, serving as an alternative to clean water. Wastewater contains traces of heavy metals that accumulate in the soil and food chain, posing an environmental and public risk. This study investigated the effect of irrigation with treated domestic wastewater (TDW) emanating from a homogenous community on heavy metal accumulation in the soil irrigated for three recurring farming cycles, namely R1, R2, and R3. A greenhouse experiment was conducted involving plots irrigated with TDW (PTw) and plots irrigated with fresh water (PFw) in triplicate. Soil samples were collected at depths of 0–20, 20–40, and 40–60 cm. Results revealed that heavy metals Pb, Cu, Cr, Zn, Cd, and Ni remained within the WHO permissible limits in the PTw and PFw, except Cd at 40–60 cm after the R3 in the TPw. Irrigation with TDW caused a decrease in Pb and Cd with respect to the baseline levels by 86–91% and 88–96% respectively. Other heavy metals increased in the soil in the order of Cr>Cu>Ni>Zn at 0–20 cm, Cr>Cu>Zn>Ni at 20–40 cm, and Cr>Cu>Ni>Zn at 40–60 cm. Variations in heavy metal concentrations were inconsistent with farming cycles except for Cu, which increased in the order of 3.2±0.75, 4.4±0.66, and 4.8±1.23 mg/kg at 0–20 cm for R1, R2, and R3, respectively, and 3.4±0.66, 3.7±0.62, and 6.0±0.44 mg/kg at 20–40 cm in the same order. Pollution index values revealed that irrigation with TDW for three recurring farming cycles caused slight soil contamination (1≤PI

The study investigates the potential of coconut husks in purifying biogas, a common issue in the use of biogas due to the high costs and environmental impact of expensive purification technologies. The study used an experimental setup generating biogas from kitchen waste and analysed its composition using an industry-standard biogas analyser. Coconut husks could remove hydrogen sulphide (H2S), with a high percentage removal efficiency of 54% at a column length of 0.5 m from the inlet. Based on the results, 2 kg of coconut husk could purify 837 L of biogas, with a removal efficiency of approximately 62%, before exhaustion. This suggests that coconut husks can be used in biogas purification to remove H2S, which is the most challenging component as it can corrode metal parts when used at high concentrations above 750 ppm. Further research is needed on large-scale purification using coconut husks at high pressure to allow more gas adsorption by the purification media.

The proton-cyclotron (PC) instability operates in various space plasma environments. In the literature, the so-called velocity moment-based quasi-linear theory is employed to investigate the physical process of PC instability that takes place after the onset of early linear exponential growth. In this method, the proton velocity distribution function (VDF) is assumed to maintain a bi-Maxwellian form for all time, which substantially simplifies the analysis, but its validity has not been rigorously examined by comparing against the actual solution of the kinetic equation. The present paper relaxes the assumption of the velocity moment-based quasi-linear theory by actually solving for the velocity space diffusion equation under the assumption of separable perpendicular and parallel VDFs, and upon comparison with the simplified velocity moment theory, it demonstrates that the simplified method is largely valid, despite the fact that the method slightly overemphasizes the relaxation of temperature anisotropy when the system is close to the marginally stable state. The overall validation is further confirmed with the results of particle-in-cell and hybrid-code simulations. The present paper thus provides a justification for making use of the velocity moment-based quasi-linear theory as an efficient first-cut theoretical tool for the PC instability.

Typical solar wind electrons are modeled as being composed of a dense but less energetic thermal “core” population plus a tenuous but energetic “halo” population with varying degrees of temperature anisotropies for both species. In this paper, we seek a fundamental explanation of how these solar wind core and halo electron temperature anisotropies are regulated by combined effects of collisions and instability excitations. The observed solar wind core/halo electron data in ( β _∥ , T _⊥ / T _∥ ) phase space show that their respective occurrence distributions are confined within an area enclosed by outer boundaries. Here, T _⊥ / T _∥ is the ratio of perpendicular and parallel temperatures and β _∥ is the ratio of parallel thermal energy to background magnetic field energy. While it is known that the boundary on the high- β _∥ side is constrained by the temperature anisotropy-driven plasma instability threshold conditions, the low- β _∥ boundary remains largely unexplained. The present paper provides a baseline explanation for the low- β _∥ boundary based upon the collisional relaxation process. By combining the instability and collisional dynamics it is shown that the observed distribution of the solar wind electrons in the ( β _∥ , T _⊥ / T _∥ ) phase space is adequately explained, both for the “core” and “halo” components.

The ability of space plasmas to self-regulate through mechanisms involving self-generated fluctuations is a topic of high interest. This paper presents the results of a new advanced quasilinear (QL) approach for the instability of electromagnetic ion-cyclotron modes driven by the relative alpha-proton drift observed in solar wind. For an extended parametric analysis, the present QL approach includes also the effects of intrinsic anisotropic temperatures of these populations. The enhanced fluctuations contribute to an exchange of energy between proton and alpha particles, leading to important variations of the anisotropies, the proton-alpha drift and the temperature contrast. The results presented here can help understand the observational data, in particular, those revealing the local variations associated with the properties of protons and alpha particles as well as the spatial profiles in the expanding solar wind.

Mohamed AbdAlla Salman,1 Mostafa Elshazli,1 Mohamed Shaaban,2 Mohamed Moustafa Esmat,3 Ahmed Salman,4 Heba Mahmoud Mohamed Ibrahim,4 Mohamed Tourky,5 Alaa Helal,5 Ahmed Abdelrahman Mahmoud,5 Feras Aljarad,6 Amr M Ismaeel Saadawy,7 Hossam El-Din Shaaban,8 Doaa Mansour1 1General Surgery Department, Kasr Al Ainy School of Medicine, Cairo University, Cairo, Egypt; 2Damietta General Hospital, General Surgery Department, Damietta, Egypt; 3Radiology Department, Kasr Al Ainy Faculty of Medicine, Cairo University, Cairo, Egypt; 4Internal Medicine Department, Kasr Al AinyFaculty of Medicine, Cairo University, Cairo, Egypt; 5General Surgery Department, Great Western Hospital, NHS Foundation Trust, Swindon, UK; 6General Surgery Department, Lewisham and Greenwich NHS Trust, London, UK; 7Radiology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt; 8Gastroenterology and Hepatology Department, National Hepatology and Tropical Medicine Research Institute, Cairo, EgyptCorrespondence: Mohamed AbdAlla SalmanGeneral Surgery Department, Associate Professor of General Surgery, Kasr Al Ainy School of Medicine, Cairo University, Cairo, EgyptTel +00201096263434Email Mohammed.salman@kasralainy.edu.egPurpose: Long-term studies reported inadequate weight loss or weight regain after laparoscopic sleeve gastrectomy (LSG). This study investigated a possible relationship between preoperative gastric volume (GV) measured by CT volumetry and weight loss one year after LSG.Methods: This prospective study included 120 patients scheduled for LSG. 3D CT gastric volumetry was done before surgery. The weight loss in the first year was serially recorded. The primary outcome measure was the correlation between preoperative GV and postoperative weight loss after one year. The secondary outcomes were the correlation between preoperative GV and other patients’ characteristics as age and body mass index (BMI).Results: Weight and BMI decreased significantly up to 12 months. The percentage of excess weight loss (%EWL) at 6 and 12 months was significantly higher than at three months. Preoperative GV was 1021 ± 253, ranging from 397 to 1543 mL. GV was not related to sex, age, weight, height, postoperative weight, and BMI.Conclusion: Preoperative gastric volume cannot predict weight loss one year after LSG. It is not correlated with age, sex, or preoperative weight, and BMI.Keywords: correlation, gastric volume, weight loss, sleeve

The subject of mutually orthogonal Latin squares (MOLSs) has fascinated researchers for many years. Although there is a number of intriguing results in this area, many open problems remain to which the answers seem as elusive as ever. Mutually orthogonal graph squares (MOGSs) are considered a generalization to MOLS. MOLS are considered an area of combinatorial design theory which has many applications in optical communications, cryptography, storage system design, wireless communications, communication protocols, and algorithm design and analysis, to mention just a few areas. In this paper, we introduce a technique for constructing the mutually orthogonal disjoint union of graphs squares and the generalization of the Kronecker product of MOGS as a generalization to the MacNeish’s Kronecker product of MOLS. These are useful for constructing many new results concerned with the MOGS.

Aflatoxins and ochratoxin A occur frequently in grains and are associated with carcinogenic, and nephrotoxic properties. Therefore, the aim of this study was to determine the level of aflatoxins and ochratoxin A contamination in wheat samples obtained from different Egyptian governorates and to assess the effect of gamma irradiation on AFB1 in spiked wheat samples, as well as to evaluate the estimated daily intake and hazard index. Thirty-six wheat grain samples purchased from different sale points were analyzed by High-Performance Liquid Chromatography. Data revealed that 33.33 % of the wheat grain samples were contaminated by aflatoxin B1, whereas only 16.66 % of the wheat samples were above the maximum limits (2 μg/kg) set by the European Commission. Ochratoxin A was only detected in two wheat grain samples, and the results were considered below the maximum limit (5 μg/kg) set by the European Commission. On studying the effect of gamma irradiation on wheat samples spiked by aflatoxin B1 (20 μg/kg), results revealed that aflatoxin B1 was reduced to 1.22 and 0.94 μg/kg for samples gamma-irradiated at a dose of 10 and 20 KGy respectively. Estimated daily intake of ochratoxin A in wheat samples was found to be higher than that of the tolerable daily intake; however, hazard index values were below one, thus demonstrating no threat to human health.

A novel approach for optimized observer feedback gains of a stable sensorless induction motor (IM) drives at very low speeds in the regenerating mode is presented. The proposed approach depends on the rough set (RS) and genetic algorithm (GA) in a cascading construction. The RS is used to obtain the most dominant machine parameters that affect the stability of the sensorless IM drive at very low speeds in the regenerating mode. The parameter's values are randomly selected to investigate their influence on the stability. Then, a reduction is obtained for the most dominant machine parameters affecting the stability. GA is applied to search for the optimal design of the observer feedback gains under the dominant parameter deviation. The proposed RS theory and GA guarantees a stable speed estimate and efficient sensorless IM drive at very low speeds in the regenerating mode. Theoretical analysis, design procedure, and simulation work of the proposed approach are presented. A sensorless IM drive is executed in the laboratory using the digital signal processor (DSP)-DS1104 control board. Extensive results in the different operating conditions to verify the efficacy of the proposed approach are presented and compared with previous works.

Instability of an adaptive flux observer (AFO) in the regenerating mode at low frequencies is a great challenge of sensorless induction motor (SIM) drives. Zero observer feedback gains (OFGs) in the regenerating mode at low frequencies are the main reasons for moving the dominant zero of the speed estimators to the unstable region. OFGs should be appropriately selected to transfer the unstable dominant zero to the stable region. In this paper, genetic algorithm (GA) and particle swarm optimization (PSO) techniques were used to design the OFGs for a stable observer. A fair comparison of the dominant zero location between the two approaches using the optimized OFGs is presented under parameter deviation. Analytical results and the design procedure of the OFGs using the two approaches are presented under deviations of stator resistance and mutual inductance to guarantee a stable dominant zero in the regenerating mode of IM. The dominant zeros obtained by PSO had a superior location to that obtained by GA for both stator resistance and mutual inductance deviations. It was observed that one of the gains had an almost constant value over a wide range of parameter deviations. However, the value of the other gain was dependent on the deviation of machine parameters. The advantage of using PSO over GA is that the relation between the gain and parameter deviation can be represented by a deterministic and mostly linear relationship. Simulation and experimental work of the SIM drive are presented and evaluated under the optimized OFGs.

Boundary layer analysis is invoked to clarify the aspects of variable thermal conductivity and thermophoretic forces on a steady state of MHD micropolar fluid flow in the existence of a uniform transverse magnetic field along an isothermal horizontal plate. The micropolar pattern permits the rotational freedom degrees that lead to couple stresses and a non symmetric stress tensor. The initiated PDEs governing the case pattern are mutated into a non-dimensional system due to proper transformations. The transformed mathematical governing equations are solved by implementing a very potent computer algebra software MATLAB code. The plotted graphs analyzed the attitude of multiple physical aspects involving factors on the flow attitude of micropolar velocity and angular velocity and temperature. Through the involved factors, the couple stress, skin friction and Nusselt number are manifested and interpreted amply. A new outcome for drag force and heat gradient experienced by the key factors is portrayed. Augmentation in Ω results in the thermophoretic forces that encapsulate the mass transmission. The local Nusselt number strengthened as the thermal conductivity, heat absorption factors or wall suction velocity were improved, and weakened due to the existence of viscous dissipation or heat generation impacts. As a particular case, the governing field equations of a classical Newtonian liquid are given by dropping the micropolar parameter impacts.

Nowadays, multi-criteria decision-making (MCDM) methods are used widely in many fields of research and applications. Many studies have shown that MCDM approaches are effective in determining the optimal solution to a variety of symmetrical and asymmetrical problems with numerous parameters. This article investigates a novel approach using multi criteria decision making (MCDM) to optimize the parameters of static var compensator (SVC) and power system stabilizers (PSS). The proposed technique integrates similarity membership function reduction algorithm (SMFRA), removal effects of criteria (REC) and combined compromise solution (CoCoSo). In the first stage, (SMFRA) is employed to select the most dominant controller parameters in the optimization process. Secondly, the weights of the reduced parameters are computed based on (REC). Finally, (CoCoSo) method searches for the optimal setting parameters. A detailed sensitivity analysis is presented to evaluate the obtained results. It is found that the suggested integrated technique is time saving, easily implemented and of low computation burden, which can successfully be implemented to solve a wide range of issues, both comparable and dissimilar.

Autonomy is considered an important criterion that characterizes the performance of electric vehicles. It is represented by the distance that could be traveled by a fully electric vehicle which mainly depends on several parameters such as the vehicle model, type of battery, type of motor, etc. In this context, to improve the autonomy of electric vehicles, this paper represents an optimization study for the electric motor based on two contributions. The first devise an energy optimization algorithm to reduce the motor losses by calculation of the stator flux reference according to the electromagnetic torque and the rotation speed. The second is concerned with controller parameters adjustment using the Particle Swarm Optimization (PSO) technique to improve the efficacy and robustness of the drive. The performance of this strategy is evaluated in terms of torque, flux ripples, and transient response to step variations of the torque control. A comparative study of the designed PI controllers based on PSO with four other control algorithms and tuning methods is established in order to prove the efficiency of PI_PSO. The analysis, modeling, and simulation results are presented to verify the validity of the proposed overall optimization study.

Diabetes mellitus is the most common cause of end-stage renal disease (ESRD) worldwide. Diabetic kidney disease (DKD) is associated with high morbidity and cardiovascular mortality. A number of guidelines and recommendations have been issued over the years recommending the use of renin-angiotensin-aldosterone system (RAAS) blockade in the management of DKD. This critical analysis takes a contrarian view, based on a selection of key clinical trials in the field, to argue that albuminuria should not be considered a target for treatment but instead a surrogate marker of DKD progression. The review also challenges, through a careful and critical analysis of a number of key clinical trials, the dogma that RAAS blockade′s benefits in DKD is beyond mere good blood pressure control. While selective and somewhat biased the authors make compelling arguments to shed serious doubt over the strength of the evidence upon which the current guidelines favoring the use of RAAS blockade in DKD are based.

To asthmatic patients with moderate to severe persistent asthma, two main treatment options are recommended: The combination of a long-acting inhaled β2-agonist with inhaled corticosteroids or the use of a higher dose of inhaled corticosteroids. The aim of this study was to evaluate which drug option is more favorable. Patients and methods: This study included 60 asthmatic patients uncontrolled on low doses of ICSs. They were randomized into two groups. Group (1): 30 patients received twice daily inhaled formetrol and budesonide in a dose of 12 mcg and 400 mcg, respectively. Group (2): 30 patients received two fold the previous dose of budesonide 800 mcg/BID alone. A comparative study was carried out at Outpatient Chest Clinic of Fayoum Hospital University for a period of 24 weeks using the spirometric data of patients of the two groups before and after treatment. Results: Results showed that the combination therapy of inhaled formetrol and budesonide is modestly more effective in the reduction of symptoms and in improving the lung functions than with a higher dose of budesonide alone. Conclusion: Adding formetrol in a dose of 12 μg plus budesonide in a dose 400 μg b.i.d. is more favorable in treatment of asthma than a higher dose of budesonide (800 μg b.i.d).