Recent publications

Genetic disorders are recognised as hereditary diseases with the most significant economic impact on horse breeding, causing important foal losses, costs of treatments of horses, and maintenance of the mare duringthe pregnancy. The Selle Francaishorses are recognized in many countries and are showing great results in equestrian sports around the world (dressage, show jumping and eventing). The study aimed to detect the presence of three mutant alleles associated with inherited diseases including Fragile Foal Syndrome (FFS), Cerebellar Abiotrophy (CA),Polysaccharide Storage Myopathy (PSSM1)and variant impacting gait type in DMRT3. This trait is important for breeding decisionin Selle Francais horses and sheds new light on genetic potential and risks on this breed. The genotyping was performed on 91 Selle Francais horses using PCR-RFLP (for POLD1; GYS1 and DMRT3genes) and PCR-ACRS (TOE1 gene) methods. The presented report indicated the presence of mutant allele A casual for PSSM1 and allele T associated with FFSsyndrome occurrence, in 4% and 6% of analysed horses, respectively. Regarding CA, the present survey did not register any cases of this genetic disorder in Selle Francais horses. Our results show also that about 1% of all the Sell Francais horses studied carry the A allele of DMRT3 gene. The present findings have provided data for these fulness of monitoring genetic diseases and gait type in the investigated breed to avoid losses of offspring.

MAX phases exhibiting magnetic properties are useful for optoelectronic devices and materials for smart coating. Here, we have investigated the elastic, electronic, magnetic, and thermodynamic properties of newly discovered ordered quaternary MAX phases (Fe0.5M0.5)2SiN (M = Cr & Mn) by using the ab-initio calculation. The Mn- and Cr-substituted Fe2SiN compounds are energetically favorable in the ferromagnetic and antiferromagnetic configurations, respectively. The magnetic properties are predicted using general gradient approximation (GGA) and along with the incorporation of the Hubbard U parameter (GGA + U). The substituted Mn- and Cr-atoms contributed the most to the total magnetic moment of these phases. Formation enthalpy and independent elastic constants confirm their thermodynamical and mechanical stabilities and their mechanical properties are anisotropic in all crystallographic planes. Electronically these phases exhibit metallicity due to the finite number of states at the Fermi level (EF). While evaluating their thermodynamic properties such as lattice parameters, heat capacity at constant volume, and Debye temperature, the (Fe0.5M0.5)2SiN phases turned out to be suitable for high-temperature applications, especially as thermal barrier coatings.

We aim in this paper to study the effect of harvesting on predator–prey interaction in the case of prey herd behavior using a fractional-order model. Herd behavior has a crucial role in the surviving of species where it gave them the sufficient protection for the prey that perform it. The objective of using the fractional-order model is to model the memory effect measured by the order of the fractional derivative on the mutual interactions. Further, we aim to seek the effect of inner competition among the predators (also super-predators) on the evolution of the three species. For the mathematical results, we will show the local stability of the equilibria, and show the effect of memory rate and harvesting of the asymptotic behavior of the solution. Moreover, an efficient numerical scheme has been used to provide the numerical illustrations for our study.

This study aimed to explore how Arabic phonological, vocabulary, and grammatical are acquired. A qualitative approach was used to deeply explore that acquisition. The results showed that the strategy of acquiring phonological aspects carried out by drilling audio listening activities, either in the form of lectures from native speakers directly or in the form of murottal, Netflix, YouTube, and online radio; while the vocabulary acquisition strategy is done by using an Arabic dictionary both online and offline, as well as reading more books, and news through online portals. Grammatical elements are acquired by directly reading nahwu and shorof books such as Jurumiyyah, Nahwu Wadhih, and Al-arabiyah baina yadaik practicing directly by studying Arabic sentences and practicing I'rab. The findings showed that the language acquisition process using various strategies can provide language acquisition of phonological, vocabulary, and grammatical aspects. Practical implications and further research to explore more diverse variables and more complex research methods are provided.

We are dealing with the classical Landau–Lifshitz equation with an unusual exchange field expressed in terms of a p -Laplacian operator for p greater than 2. We obtain weak solutions to the model by using penalization, compactness arguments, and monotonicity method.

The particle size is one of the most important factors influencing the behavior of soils. To study the impact of extreme particle diameters (Dmax and Dmin) and mean grain diameter (D50), a series of undrained triaxial compression tests were carried out with eighteen loose natural river sandy samples; considering a maximum particle diameter range (1.60 mm ≤ Dmax ≤ 4.00 mm), mean particle size ranges (0.25 mm ≤ D50 ≤ 1.00 mm) and the same minimum diameter Dmin = 0.0016 mm for the group1. For the group 2 consists of sandy samples having maximum diameter Dmax = 4.00 mm, minimum particle diameter ranges (0.0016 mm ≤ Dmin ≤ 0.63 mm), and mean diameter range (1.00 mm ≤ D50 ≤ 2.50 mm). The sandy samples were prepared with initial relative density Dr = 25% and subjected under a constant confining pressure (P’c = 50 kPa). The obtained test results indicate that the extreme particle diameters have significant effects on mechanical response of sandy soils and appear as important parameters for the prediction of the undrained shear strength of the tested soils. The maximum shear resistance can be correlated to the maximum relative diameter (Dmax/D50) and minimum relative diameter (Dmin/D50) of the tested samples.

This paper presents a computational analysis of some physical properties of Ba2YBiO6 double perovskite, using full potential density functional theory (DFT) calculations. Our study demonstrates that the calculated lattice constant agrees well with the experimental one. The electronic structure results show that Ba2YBiO6 is a p-type indirect band-gap semiconductor, with bandgap of 2.87 eV. The optical properties are explored with reflectivity (R (𝜔)), refractive index (n (𝜔)), energy loss function
(𝐸𝑙𝑜𝑠𝑠 (ω)), complex dielectric constant (𝜀 (𝜔)), absorption coefficient (𝛼 (𝜔)), and optical conductivity (𝜎 (𝜔)). Furthermore, for thermoelectric response of the material examined with the Seebeck coefficient (S) and the electrical conductivity (σ/𝜏), showed that holes are the majority carriers demonstrating semiconducting nature of the material. These findings suggest that double perovskite Ba2YBiO6 could fit for ultraviolet (UV) and visible-light optoelectronic devices, and thermoelectric applications.

Résumé
La sémiotricité se propose comme un moyen incontournable si l’on veut approfondir les registres symboliques de l’action motrice. Dans le domaine de l’éducation physique et sportive, les élèves apprennent à identifier et à détecter des indices signifiants dans l’environnement physique dans lequel ils évoluent. Un élève en situation de jeu, observe les comportements d’autrui et apprend à deviner les prolongements de leurs actes en vue d’anticiper des enchaînements d’actions et à conformer ses conduites aux comportements qu’il pré-perçoit. Ce faisant, il participe à un processus de symbolisation ou de sémiotricisation.
Étant entendu que cette sémiotricisation est liée à la logique interne de la pratique, il est clair que l’adaptabilité sémiotrice dépondra des caractéristiques des activités retenues dans les programmes pédagogiques. Cet article se propose, à partir d’une analyse comparative entre trois programmes d’Education Physique et sportive (Algérie, France, et Espagne), et des corpus d’études traitant de cette question, de mettre en premier plan l’importance des choix pédagogiques dans l’accès à la symbolisation et dans la construction de la personnalité de l’enfant.

In this paper, we aim to analyze the effect of treatment and protection measures on the spread of infectious disease. Therefore, we formulate a delayed mathematical which contains a discrete delay which stands for the duration of protection and distributed delay that represents the repulsed individuals from treatment. The main result is to show that the model has threshold behavior governed by [Formula: see text]. For [Formula: see text], it is shown that the disease-free equilibrium is globally stable. However, for [Formula: see text], it is proved that the semiflow is uniformly persistent, and the endemic equilibrium is globally stable. Another purpose is fixed in this paper, which consists of studying the effect of treatment and protection measures on the spread of the disease, and to distinguish the minimal protection and treatment measure for reducing the basic reproduction number below one. The results are supported numerically using numerical simulations.

This paper presents a simple and an efficient formulation of wave motions in partially saturated poroviscoelastic soil media. The viscoelastic property of the solid skeleton is incorporated into the elastic moduli via a simple relationship between the skeleton damping and the relaxation time established based on the Kelvin-Voigt model. The proposed formulation is adaptable to various soil configurations. It has been successfully applied to some vibrational problems of nearly-saturated soil columns made of different materials and carrying different loadings. The consideration of the skeleton damping, which does not receive a sufficient attention in previous works unlike the Biot flow - induced damping, significantly reduced the motion amplification amplitudes as well as the accelerations and Fourier spectra amplitudes at the surface of actual sites. As a useful application of the present formulation, the motions obtained at the ground surface of actual sites have been applied as inputs to a wind turbine to obtain its response in the time domain. The maximal relative displacements of the turbine were substantially reduced due to the skeleton damping. The vertical response of the turbine still negligible compared to the horizontal response.

In this paper we study the global (in time) existence of small data Sobolev solutions to the Cauchy problem for semilinear σ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\sigma $$\end{document}-evolution models with friction and visco-elastic damping and with a power nonlinearity, namely, utt+(-Δ)σu+ut+(-Δ)σut=||D|au|p,u(0,x)=0,ut(0,x)=u1(x),\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\begin{aligned} \left\{ \begin{array}{ll} u_{tt}+ (-\Delta )^\sigma u + u_t +(- \Delta )^\sigma u_t=\big ||D|^au\big |^p,\\ u(0,x)=0,\quad u_{t}(0,x)=u_1(x),\end{array} \right. \end{aligned}$$\end{document}where σ≥1\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\sigma \ge 1$$\end{document}, p>1\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p>1$$\end{document}, and the data u1∈Lm(Rn)∩Hqs-2σ(Rn)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$u_1\in L^m(\mathbb {R}^n) \cap H^{s-2\sigma }_q(\mathbb {R}^n) $$\end{document}with s≥2σ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$s\ge 2\sigma $$\end{document}, q∈(1,∞)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$q\in (1,\infty )$$\end{document} and m∈[1,q)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$m\in [1,q)$$\end{document}. In the power nonlinearity we suppose a∈[0,2σ)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$a\in [0,2\sigma )$$\end{document}. We are interested in connections between regularity assumptions for the data and the admissible range of exponents p in the power nonlinearity.

Multi-resistant bacterial pathogens are a major public health problem for treating nosocomial infections owing to their high resistance to antibiotics. The objective of this research was to characterize the bioactive molecules secreted by a novel moderately halophilic actinobacterium strain, designated GSB-11, exhibiting a strong antagonistic activity against several multidrug-resistant pathogenic bacteria. This potential strain was identified by phenotypic, genotypic (16S rRNA), and phylogenetic analyses. GSB-11 was related to “Streptomyces acrimycini” NBRC 12736 T with 99.59% similarity. Molecular screening by PCR assay demonstrated that the strain possesses two biosynthetic genes coding for NRPS and PKS-II. Two active compounds GSB11-6 and GSB11-7 were extracted from the cell-free culture supernatant of Bennett medium and purified using reversed-phase HPLC. According to spectrometric (mass spectrum) and spectroscopic (¹H NMR, ¹³C NMR, ¹H-¹H COSY, and ¹H-¹³C HMBC) spectra analyses, the compounds GSB11-6 and GSB11-7 were identified to be maculosin and N-acetyltyramine, respectively. Their minimum inhibitory concentrations (MIC) revealed interesting values against certain multidrug-resistant pathogenic bacteria. They were between 5 and 15 mg/mL for GSB11-6, 10 and 30 mg/mL for GSB11-7. To our best knowledge, this is the first study of these active substances isolated from “Streptomyces acrimycini” showing an interesting antibacterial activity. Therefore, these essential compounds could be candidates for future research against multidrug-resistant bacteria.

The role of climate change in future streamflow is still very uncertain, especially over semi-arid regions. However, part of this uncertainty can be offset by correcting systematic climate models’ bias. This paper tries to assess how the choice of a bias correction method may impact future streamflow of the Cheliff-Mactaa-Tafna (CMT) rivers. First, three correction methods (quantile mapping (QM), quantile delta mapping (QDM), and scaled distribution mapping (SDM)) were applied to an ensemble of future precipitation and temperature coming from CORDEX-Africa, which uses two Representative Concentration Pathways: RCP4.5 and RCP8.5. Then, the Zygos model was used to convert the corrected time series into streamflow. Interestingly, the findings showed an agreement between the three methods that revealed a decline in future streamflow up to [−42 to −62%] in autumn, [+31% to −11%] in winter, [−23% to −39%] in spring, and [−23% to −41%] in summer. The rate of decrease was largest when using QM-corrected model outputs, followed by the raw model, the SDM-corrected model, and finally, the QDM-corrected model outputs. As expected, the RCP presents the largest decline especially by the end of the 21st Century.

A few empirical models for the axial loading capacity (ALC) of circular normal strength concrete (NSC) columns wrapped by carbon fiber reinforced polymer (CFRP) sheets and interior transverse steel reinforcement (TSR) (CSC columns) are available in the literature. The deficiency of those models is that they were proposed based on a small number of tests by considering limited parameters of CSC columns. Therefore, the main aim of the current investigation is to propose the improved empirical models for the ALC of CSC columns by including the interaction mechanism between TSR and FRP confining behavior. To secure this aim, a general regression analysis technique and artificial neural networks (NNs) on the experimental outcomes of 76 CSC columns collected from the previous investigations were employed. The proposed NN model was adjusted for the different number of hidden layers and neurons to achieve an optimized model. The suggested NN and empirical models portrayed a close agreement with the testing database with R2 = 0.998 and R2 = 0.892, respectively. The NN model reported a higher accuracy than the theoretical model. The comparative investigation solidly authenticated the superiority and accuracy of the anticipated strength models for CSC columns.

The aim of this work is to simultaneously evaluate the effects of inhomogeneous strain-induced and anisotropy on the friction during the deep drawing of DC06EK sheet metal. To do that, stretched and unstretched DC06EK strips in different rolling directions (0°, 45° and 90°) with different levels of equivalent plastic strain were used in microscratch tests under the same conditions as those used in deep drawing process (DDP) coming from a local industry. The findings show that the coefficient of friction (COF) decreases as a function of the equivalent plastic strain for different rolling directions. Two empirical friction laws are obtained depending on the equivalent plastic strain following 0° and 90° to the rolling direction. Since the COF have a clear trend of regression except in the case for 45°. Trend lines of the COF following 0° and 90° converge to very closely values, since the effect of anisotropy disappears with the increase in the level of plastic strain.

The aim of this work is to simultaneously evaluate the effects of inhomogeneous strain-induced and anisotropy on the friction during the deep drawing of DC06EK sheet metal. To do that, stretched and unstretched DC06EK strips in different rolling directions (0°, 45° and 90°) with different levels of equivalent plastic strain were used in microscratch tests under the same conditions as those used in deep drawing process (DDP) coming from a local industry. The findings show that the coefficient of friction (COF) decreases as a function of the equivalent plastic strain for different rolling directions. Two empirical friction laws are obtained depending on the equivalent plastic strain following 0° and 90° to the rolling direction. Since the COF have a clear trend of regression except in the case for 45°. Trend lines of the COF following 0° and 90° converge to very closely values, since the effect of anisotropy disappears with the increase in the level of plastic strain.

In this work, we study existence and uniqueness of solutions for multi-point boundary value problemS of nonlinear fractional differential equations with two fractional derivatives. By using a variety of fixed point theorems, such as Banach's fixed point theorem, Leray-Schauder's nonlinear alternative and Leray-Schauder's degree theory, the existence of solutions is obtained. At the end, some illustrative examples are discussed.

The aim of this paper is to analyze the temporal tendencies of monthly, seasonal, and annual rainfall and runoff in the Wadi Mina basin (north-western side of Africa) using data from five stations in the period from 1973–2012. With this aim, first, a trend analysis was performed using two non-parametric tests: the Theil–Sen estimator and the Mann–Kendall test. Then, to identify trends in the different rainfall and runoff values of the series, the Innovative Trend Analysis technique was further applied. The results of the application of the non-parametric tests on the rainfall data showed a general negative rainfall trend in the Wadi Mina basin for different timescales. Similarly, the results evidenced a general reduction in the runoff values, in particular in the Sidi Abdelkader Djillali and Oued Abtal stations, even though the results obtained for the Oued Abtal station are influenced by a dam. These results were further analyzed through Sen’s method, which enabled the trend identification of the different values (low, medium, and high) of the series.

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