Intracellular localization of samarium in the lactating mammary gland cells: ultrastructural and microanalytical study

The frequent use of some rare earths in the medical and industrial domains make us worry about their intracellular behavior into the body. Reason for which we have investigated the subcellular localization of one of these elements, the samarium, in the mammary gland of lactating female wistar rats using two very sensitive methods of observation and microanalysis, the transmission electron microscopy and the secondary ion mass spectrometry. The ultrastructural study showed the presence of electron dense deposits in the lactating mammary glandular epithelial cell lysosomes of the samarium-treated rats, but no loaded lysosomes were observed in those of control rats. The microanalytical study allowed both the identification of the chemical species present in those deposits as samarium isotopes ((152) Sm(+)) and the cartography of its distribution. Our results confirm the previous ones showing that lysosomes of the glandular epithelial cells are the site of the intracellular concentration of foreign elements such as gallium. The intralysosomal deposits observed in the mammary glandular cells of the samarium-treated rats are similar in their form and density to those observed with the same element in other varieties of cells, such as liver, bone marrow, and spleen cells. Our ultrastructural and microanalytical results and those obtained in previous studies allow deducing that the intralysosomal deposits are very probably composed of an insoluble samarium phosphate salt.     

Enhancing the Tribological Behavior of Lubricating Oil by Adding TiO2, Graphene,and TiO2/Graphene Nanoparticles

This article investigates the tribological behavior of nanoparticles (NPs) of titanium dioxide anatase TiO₂ (A), graphene, and TiO₂ (A) + graphene added to the pure base oil group ΙΙ (PBO-GΙΙ). The morphology of these two nanostructures of TiO₂ (A) and graphene was characterized by transmission electron microscopy (TEM). Oleic acid (OA) was blended as a surfactant into the formulation to help stabilize the NPs in the lubricant oil. A four-ball test rig was used to determine the tribological performance of six different samples, and an image acquisition system was used to examine and measure the wear scar diameter of the stationary balls. Field emission–scanning electron microscopy (FE-SEM) was used to examine the wear morphology. Energy-dispersive X-ray spectroscopy (EDX), element mapping, and Raman spectroscopy were employed to confirm the presence of (TiO₂ (A) + graphene) and the formation of a tribolayer/film on the mating surfaces. Moreover, a 3D optical surface texture analyzer was utilized to investigate the scar topography and tribological performance. The experiments proved that adding (0.4?wt% TiO₂ (A) + 0.2?wt% graphene) to the PBO-GΙΙ optimized its tribological behavior. These excellent results can be attributed to the dual additive effect and the formation of a tribofilm of NPs during sliding motion. Furthermore, the average reductions in the coefficient of friction (COF), wear scar diameter (WSD), and specific wear rate (SWR) were 38.83, 36.78, and 15.78%, respectively, for (0.4?wt% TiO₂ (A) + 0.2?wt% graphene) nanolubricant compared to plain PBO-GΙΙ lubricant.     

The excellent photocatalytic activity of novel Cs3PW12O40/WO3 composite toward the degradation of rhodamine B

In this paper, a simple one-pot thermal decomposition method was successfully used to synthesize a novel Cs₃PW₁₂O₄₀/WO₃ composite for the first time. The synthesized composite was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), FTIR, diffuse reflectance spectroscopy (DRS) and N₂ adsorption-desorption techniques. The photocatalytic activity to degrade RhB molecules over Cs₃PW₁₂O₄₀/WO₃ composite was evaluated under xenon light irradiation. The results indicated the complete degradation of RhB molecules over Cs₃PW₁₂O₄₀/WO₃ composite after 30?min irradiation. However, the photocatalytic degradation of RhB over WO₃ and Cs₃PW₁₂O₄₀ after 80?min light irradiation are nearly 52%, and 68%, respectively. The enhanced photocatalytic activity of Cs₃PW₁₂O₄₀/WO₃ composite compared with WO₃, and Cs₃PW₁₂O₄₀ was ascribed to the strong interaction between WO₃ and Cs₃PW₁₂O₄₀, which effectively reduces the recombination of photogenerated electron-hole pairs. Based on experimental results, the possible mechanism of photocatalytic reactions on the Cs₃PW₁₂O₄₀/WO₃ composite photocatalyst was investigated, and the hydroxyl radical (OH) and superoxide radical (O₂^?) were determined as the main active species in the photocatalytic degradation of RhB over Cs₃PW₁₂O₄₀/WO₃ composite.     

High Performance Removal of Anionic and Cationic Dye Pollutants with Co<Subscript>3</Subscript>O<Subscript>4</Subscript> Modified Nanoclinoptilolite: Kinetics and Adsorption Equilibrium Studies

In this paper Co₃O₄ doped nanoclinoptilolite was synthesized and characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR), field emission scanning electron microscopy (FESEM) and energy-dispersive X-ray spectroscopy (EDX) techniques. The adsorption efficiency for removing of methylene blue was about 95% in 10 min. The effect of some factors such as adsorbent dose, concentration of analyte and pH was investigated for enhancing the removing efficiency. Moreover Freundlich and Langmuir patterns were plotted for this new nanocomposite. Maximum of adsorption capacity was obtained from slope of Langmuir and was about 25 mg/g. The kinetic study for methylene blue shows a second order kinetic with rate constant about 0.02 g/mg/min. The prepared nanocomposite was successfully applied for removing some color compounds such as methylene blue, methyl green, and methyl red and also binary dye mixtures.     

Multi-band Tight-Binding Model of MoS 2 Monolayer

In this theoretical study, the band structure of MoS2 monolayer was initially numerically calculated using an 11-band tight-binding Hamiltonian model. Then, the contributions of d and p orbitals on the density of states (DOS), electronic heat capacity (EHC), and Pauli magnetic susceptibility (PMS) of the system were investigated based on the mentioned model and the Green’s function method. Also, the temperature dependence of the EHC and PMS is compared for the d and the p orbitals. An obvious gap was observed in the band structure and DOS of the MoS2 monolayer system, which is in good agreement with previous works. Moreover, due to the orbital overlap, Van Hove singularities appear. Then, as a result of this, a crossover occurs in the curves of PMS, which are divided into a low- and high-temperature region. Further, a Schottky anomaly is observed in the EHC curves. Overall, in this paper, we have introduced a method to investigate the electronic properties of $${{ {MoS}}}_{2}$$ monolayer that can be applied to other monolayer dichalcogenides.     

Design of a Symmetric CPW-Fed Patch Antenna for WLAN/WIMAX Applications Using ANN

The upper bound capacity based on the SINR model is a very important parameter when evaluating the performance of the multi-hop wireless ad hoc networks. In this paper, a new upper bound capacity algorithm is proposed. Firstly, we analyzed the classical physics SINR model over the Rayleigh fading channels to establish the relationship between density of nodes and path outage probability. Then, we developed the closed-form expression of the upper bound transmission capacity based on the Weber model for the random networks. Finally, we evaluated effects of parameters in the communication range, density, SINR threshold and fading factors, and consequently transmission capacity of the network by sensitivity analysis. The numerical simulation showed that the optimum density of nodes was existed to obtain the upper bound transmission capacity. The capacity increased firstly and then decreased over the density of nodes increasing. It affected by channel fading factor and communication range sensitively.

     

Toward a boundary regional control problem for Boolean cellular automata

An important question to be addressed regarding system control on a time interval [0, T] is whether some particular target state in the configuration space is reachable from a given initial state. When the target of interest refers only to a portion of the spatial domain, we speak about regional analysis. Cellular automata approach have been recently promoted for the study of control problems on spatially extended systems for which the classical approaches cannot be used. An interesting problem concerns the situation where the subregion of interest is not interior to the domain but a portion of its boundary . In this paper we address the problem of regional controllability of cellular automata via boundary actions, i.e., we investigate the characteristics of a cellular automaton so that it can be controlled inside a given region only acting on the value of sites at its boundaries.     

Novel design and simulation of reversible ALU in quantum dot cellular automata

The Journal of Supercomputing - Quantum dot cellular automata (QCA) technology is considered as one of the most suitable replacements to reduce the CMOS-based digital circuit design problems at the...     

Adaptive discrete-time sliding-mode control of nonlinear systems described by Wiener models

In this paper, we propose an adaptive control scheme that can be applied to nonlinear systems with unknown parameters. The considered class of nonlinear systems is described by the block-oriented models, specifically, the Wiener models. These models consist of dynamic linear blocks in series with static nonlinear blocks. The proposed adaptive control method is based on the inverse of the nonlinear function block and on the discrete-time sliding-mode controller. The parameters adaptation are performed using a new recursive parametric estimation algorithm. This algorithm is developed using the adjustable model method and the least squares technique. A recursive least squares (RLS) algorithm is used to estimate the inverse nonlinear function. A time-varying gain is proposed, in the discrete-time sliding mode controller, to reduce the chattering problem. The stability of the closed-loop nonlinear system, with the proposed adaptive control scheme, has been proved. An application to a pH neutralisation process has been carried out and the simulation results clearly show the effectiveness of the proposed adaptive control scheme.     

Robust self-tuning control based on discrete-time sliding mode for auto-regressive mathematical model in the presence of unmodelled dynamics

In this paper, we propose a new robust self-tuning control, called the generalized minimum variance αl-equivalent selftuning control (GMVSTC-αl) for the linear timevarying (LTV) systems, which can be described by the discrete-time auto-regressive exogenous (ARX) mathematical model in the presence of unmodelled dynamics. The estimation of the parameters contained in this mathematical model is made on the basis of the proposed modified recursive least squares (m-RLS) parametric estimation algorithm with dead zone and forgetting factor. The stability analysis of the proposed parametric estimation algorithm m-RLS is treated on the basis of a Lyapunov function. A numerical simulation example is used to prove the performances and the effectiveness of the explicit scheme of the proposed robust self-tuning control GMVSTC-αl.