Homogenization of Elliptic Problems with Quadratic Growth and Nonhomogenous Robin Conditions in Perforated Domains

This paper deals with the homogenization of a class of nonlinear elliptic problems with quadratic growth in a periodically perforated domain. The authors prescribe a Dirichlet condition on the exterior boundary and a nonhomogeneous nonlinear Robin condition on the boundary of the holes. The main difficulty, when passing to the limit, is that the solution of the problems converges neither strongly in L~2(Ω) nor almost everywhere in Ω. A new convergence result involving nonlinear functions provides suitable weak convergence results which permit passing to the limit without using any extension operator.Consequently, using a corrector result proved in [Chourabi, I. and Donato, P., Homogenization and correctors of a class of elliptic problems in perforated domains, Asymptotic Analysis, 92(1), 2015, 1–43, DOI: 10.3233/ASY-151288], the authors describe the limit problem, presenting a limit nonlinearity which is different for the two cases, that of a Neumann datum with a nonzero average and with a zero average.     

Hydrothermal Synthesis,Structural and Optical Elucidation with Hirshfeld Surface Analysis of a Bioactive Hybrid Compound Based Mixed-Metal Cluster Anion [V<Subscript>2</Subscript>W<Subscript>4</Subscript>O<Subscript>19</Subscript>]<Superscript>4−</Superscript>

A mixed-metal Lindqvist-type heteropolyanion of organic cation; (C₈H₁₄N₂)₂[V₂W₄O₁₉]?2H₂O (m-XDAV2W4) has been synthesized hydrothermally and characterized by means ICP and elemental analysis, X-ray diffraction, IR, UV–Vis, luminescence and biological analyses. The X-ray structural analysis supported by a detailed Hirshfeld surface analysis and fingerprint plots has been elucidated the different inter-contacts in the crystal structure mainly associated with O…H/H…O close contacts between [V₂W₄O₁₉]^4? (V2W4) clusters, water molecules and m-xylylenediammonium entities so stabilizing the 3D-supramolecular structure. The optical survey reveals an important HOMO–LUMO band gap indicating stability and blue luminescent behavior of reported material. Moreover, the biological trials indicated that this compound displays promising antibacterial and antifungal activities.     

The Influence of the Extent of Enzymatic Hydrolysis on Antioxidative Properties and ACE-Inhibitory Activities of Protein Hydrolysates from Goby (Zosterisessor ophiocephalus) Muscle

Antioxidant properties and angiotensin-converting enzyme (ACE) inhibitory activities of protein hydrolysates from goby (Zosterisessor ophiocephalus) muscle, with different degrees of hydrolysis (DH) from 5 to 25 %, prepared by treatment with crude proteases extract from smooth hound intestines, were investigated. Goby protein hydrolysates (GPHs) are rich in Gly and Thr, which accounted for 14.1–15 % and 11.6–13.2 % of the total amino acids, respectively. The antioxidant activities of GPHs were investigated by using several in vitro assay systems. All GPHs exhibited significant metal chelating activity and DPPH free radical-scavenging activity, and inhibited linoleic acid peroxidation. For the ACE-inhibitory activity, as the DH increased, the activity of GPHs increased. The obtained results revealed that antioxidant and ACE-inhibitory activities of GPHs were influenced by the degree of hydrolysis. A medium degree of enzymatic hydrolysis was appropriate to obtain GPHs with good antioxidant activity, while small peptides were essential to obtain high ACE inhibitory activity.     

Synthesis and biological evaluation of 99mTc-ECF: a new ethionamide derivative for tuberculosis diagnosis

In this work we propose a technetium-99m-labeled derivative from Ethionamide (ETH), further referred to as ^99mTc-ECF for tuberculosis diagnosis. The biological features of this radioactive agent have been studied. The 2-ethylpyridine-4-carbothioamide-ferrocène (ECF) was chemically synthesized and then labeled with technetium-99m. It has been confirmed through this work that ^99mTc-ECF is obtained with high radiolabelling yield (>90 %). Radiochemical analysis of ^99mTc-ECF revealed that the molecule was efficiently labeled with a little free remaining pertechnetate. Only 1–2 % of the tracer was leached out from the complex at 24 h when incubated in serum at 37 °C which confirmed its high stability. The sensitivity test of ECF showed that the group of grafted ferrocenyl does not seem to have largely altered the active site of the molecule. In-vitro investigations were conducted using BCG (Bacille Calmette-Guérin) as analogue of Mycobacterium Tuberculosis and Listeria Monocytogenes as negative control. It was proved that for BCG, ECF has kept the bacteriostatic properties of the parent compound (ETH). In physiological conditions, the measured up-take of the tracer with live bacteria was about 24.1 and 7.1 % for BCG and Listeria Monocytogenese, respectively. The comparison of the ^99mTc-ECF accumulation at sites of BCG infected animals, which is expressed as target-to-non-target ratio (found to be equal to 2.15) with other radiotracers was discussed. This allowed us to consider that ^99mTc-ECF could be a reasonable radiotracer for mycobacterial infections. Obtained results were good and encourage to undergo a similar labeling for the Mycobacterium tuberculosis as perspective of this work.     

Thermal behavior and physicochemical studies of phase transitions before the decomposition in the selenate–tellurate protonic conductor material

Journal of Thermal Analysis and Calorimetry - Thermal analysis confirmed the presence of the phase transition at T?=?320&nbsp;K in the Cs2SeO4·H6TeO6 (CsSeTe) material. The...     

Evaluation and modeling of synergy to pheromone and plant kairomone in American palm weevil

Background  

Many behavioral responses to odors are synergistic, particularly in insects. In beetles, synergy often involves a pheromone and a plant odor, and pest management relies on them for the use of combined lures. To investigate olfactory synergy mechanisms, we need to distinguish synergistic effects from additive ones, when all components of the mixture are active.     

Simple-Complex Fluid Transition in Microemulsions

The aim of this work was to study the rheological behavior of water in-oil microemulsion formulated with AOT (sodium bis(2-ethylhexyl) sulfoccinate) in isooctane over a temperature range from 25°C to 55°C for the oil/AOT volume fraction φ _m =0.1 and various AOT and H₂O molar ratios, W₀, ranging from 0 to 45. The apparent viscosity was measured vs. shear rate by a rotational concentric cylinder viscometer. It was shown that above s^?1, the solutions utilized behaved as Newtonian liquids. The absolute viscosities were deduced from the shear stress- shear rate rheograms. For W₀ < 17, the solutions behaved as simple fluids, where the viscosities decrease as the temperature increases. However, an opposite behavior was observed for W₀ > 17; the viscosity remained constant and then increased above a critical temperature, T_c, depending on W₀. For the molar ratio W_0,c = 17; the studied viscosity remained constant, η(W_0,c) = (1.17 ± 0.04) cP, for the temperature range studied. Thus, a simple–complex fluid transition was evident in the studied system. For the simple fluids, W₀ < W_0,c, the total activation energy vs. W₀ showed three linear parts. The different slopes were attributed to the change of the microscopic structure of the formed micelles. For the critical molar ratio W_0,c = 17, the total activation energy vanished. So, according to the Eyring lattice model, the jump of the formed micelles from one site to another was not permitted and the entire molecular groups were in vibration and rotation motions. For W₀ > W_0,c, where the formed micelles were fully hydrated, the relative viscosity of the studied solutions vs. temperature was fitted according a polynomial law, where the exponent was found to be dependent on W₀.