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An edge dislocation with a time-dependent Burgers vector in an orthotropic plane is analyzed. The stress field caused by a dynamic point force in the intact plane is determined. The displacement discontinuity of dislocation and direction of point load are at arbitrary angles with the Material Principal Axes (MPA), the general orthotropic plane. The density of dislocations is employed to construct integral equations for orthotropic planes weakened by several interacting cracks, making arbitrary angles with the MPA. The numerical solution of integral equations results in the density of dislocations on a crack surface. The results are employed to determine time-dependent Stress Intensity Factors (SIFs) at the tips of a crack and Crack Opening Displacement (COD). In the problem of general orthotropic planes containing cracks subjected to dynamic loads, crack orientations may cause their partial/total closing. Under the hypothesis of frictionless contact, we devise an iterative procedure to handle crack closing, as well. By contrast to cracks in the directions of MPA, expressions for the two modes of SIFs contain the density functions of both the climb and glide of the edge dislocation. Therefore, mode I SIF at an open tip of a crack may not be positive. Conversely, positive mode I SIF may occur at a closed crack tip. Numerical results of the SIFs and COD for several examples of orthotropic planes under dynamic point loads, while weakened by single and double parallel cracks, are presented. Moreover, in double cracks cases, the interaction between cracks is studied. [ABSTRACT FROM AUTHOR]

In this paper, we studied the thermodynamic quantities of dyonic ModMax and Taub-NUT black holes (BHs) to investigate their universal relations, viz. that product formulas are mass-independent. So, we calculated the thermodynamic parameters of these BHs in the inner and outer event horizons. We also obtained information about the left and right central charges. We showed that the central charges are not independent of the mass, i.e., they do not correspond to the conformal field theory (CFT). Also, we showed that the two sides of the central charge for the Taub-NUT BH are the same. These results play an important role in improving AdS/CFT and holography and thermodynamic studies. Finally, we compared our results with the other works in the literature. [ABSTRACT FROM AUTHOR]

The analysis of an intact elastic layer resting on a flexible foundation subjected to patch-loads moving with a constant velocity, on the layer-free boundary, is carried out. Structural energy dissipation is modeled by viscous damping. Quasi-static analysis of edge dislocation is accomplished. Based on these solutions, integral equations are derived for a crack perpendicular to the boundary of layers under moving patch-loads. Dynamic excitation may partially/completely close the crack surface. Crack closing, in the absence of friction, is taken into account. The effects of load velocity and energy dissipation on crack stress intensity factors and opening displacement are investigated. [ABSTRACT FROM AUTHOR]

The study of various relations between different quantities is of great importance in thermodynamics. Hence in this paper, we will discuss a specific thermodynamic relation between entropy (S) and temperature (T) of some of the black holes. Therefore, we will choose Kerr, Kerr–Newman and charged BTZ black holes. Then we will calculate the relations between the thermodynamic quantities and explain the results in detail. Here, we study a special type of duality-like behaviour that occurs in the thermodynamics of black holes while preserving the laws of thermodynamics. The relationship between entropy and temperature is calculated as S ± T ± = γ / 2 for the Kerr and Kerr–Newman black holes and S ± T ± = γ 2 / 4 for the charged BTZ black holes. [ABSTRACT FROM AUTHOR]

One of the most important issues in cosmology is the study of a series of hypothetical objects called wormholes. Recently, researchers have studied these hypothetical objects under different conditions. In this paper, we aim to evaluate the traversable wormhole according to a modified f (R) gravitational model, specifically − R 2 + a R 2 (1 − n) , from the perspective of two essential functions in wormhole structure: shape and redshift function. These hypothetical objects can solve Einstein's equations by tolerating the violation of null energy conditions (NEC). With respect to these concepts, we examine various energy conditions such as the NEC, weak energy condition (WEC), dominant energy condition (DEC) and strong energy condition (SEC) using radial pressure, tangential pressure and energy density obtained from the wormhole equations. Finally, we evaluate different energy conditions by plotting some figures and checking for satisfaction or violation. We will analyze the results and present the conclusions in tables. [ABSTRACT FROM AUTHOR]

In this paper, we study a particular type of inflation by using non-local Friedman equations that are derived from the zero levels of string field theory and express a tachyonic action. Then, we challenge it by further refining de Sitter (dS) swampland conjecture (FRdSSC) monitoring. Therefore, we investigate some quantities, such as potential and Hubble parameters. We also consider slow-roll parameters to examine quantities such as the scalar spectrum index and the tensor-to-scalar ratio. Using straightforward calculations, we investigate this model from the swampland conjecture perspective in terms of the cosmological parameters, i.e., ( n s ), (r), and observable data such as Planck 2018, by constructing some structures such as (c 1 , 2 - n s) and (c 1 , 2 - r s) . Then, we make a new restriction for this conjecture as c 1 2 c 2 2 and get a limit for this model in the range c < 0.0942 . We find this inflationary model is strongly in tension with the dS swampland conjecture (dSSC), i.e., c 1 = c 2 ≠ O (1) . So, we shall challenge it with the FRdSSC, which has some free parameters, viz., a , b > 0 , a + b = 1 , and q > 2 . By setting these parameters, we examine the compatibility of the mentioned conjecture with this inflationary model. Finally, we infer from this string field inflation (SFI) model that it satisfies the FRdSSC with the constraint of its free parameters a, b, and q. [ABSTRACT FROM AUTHOR]

In this paper, we study two different dynamic structures of holographic dark energy, namely Tsallis and Kaniadakis, within the framework of Brans–Dicke cosmology. We consider the complex form of the quintessence model and examine both non-interacting and interacting cases, calculating various cosmological parameters such as the equation of state ω and discussing the behavior of ω − ω ′ . We modify the potential and study the scalar field dynamics of complex quintessence cosmology. Additionally, we examine the effects of the two parts of the quintessence field (real and complex) and the fractional energy density Ω D , determining whether they can describe a real universe. We note that the fractional energy density cannot be arbitrary between 0 and 1, as it depends on the Tsallis, Kaniadakis and Brans–Dicke cosmology-free parameters. For each model, we establish a relationship between the fractional energy density and other parameters such as δ , b 2 , α and β. [ABSTRACT FROM AUTHOR]

In light of an expanded theory of f(R, T) gravity with the matter field as a viscous fluid, this paper evaluated an accelerated cosmology model in the anisotropic space–time. A variable Hubble parameter was used to investigate dynamic parameters concerning red-shift and the effect of the viscous coefficient. By explicitly calculating the energy density using the equations of motion, we examine the variations of these values in terms of red-shift z for different variables. The model is formed by a mathematical method, and the equation of motion parameter shows a quintessence behaviour at the late-time cosmic acceleration. We calculate the other energy conditions, i.e., NEC, WEC and SEC, evaluating their changes with cosmic time. Finally, we compare the quantities with the latest observable data, from the Planck and WMAP7 probes. [ABSTRACT FROM AUTHOR]

Mimetic gravity analysis has been studied as a theory in various types of general relativity extensions, such as mimetic f (R) gravity, mimetic f (R , T) gravity, mimetic f (R , G) gravity, etc. in the literature. This paper presents a set of equations arising from mimetic conditions and studies cosmic inflation with a combination of mimetic f (G) gravity and swampland dS conjectures. We analyze and evaluate these results. Therefore, we first thoroughly introduce the mimetic f (G) gravity and calculate some cosmological parameters such as the scalar spectral index, the tensor-to-scalar ratio, and the slow-roll parameters. Also, we investigate the potential according to the mimetic f (G) gravity. Then we will challenge the swampland dS conjectures with this condition. By expressing the coefficient of swampland dS conjectures viz C 1 and C 2 in terms of n s and r , we plot some figures and determine the allowable range for each of these cosmological parameters and these coefficients, and finally, compare these results with observable data such as Planck and BICEP2/Keck array data. We show C 1 and C 2 are not (1) , so the refining swampland dS conjecture is not satisfied for this inflationary model. Then we examine it with further refining swampland dS conjecture, which has a series of free parameters such as a , b > 0 , q > 2 and a + b = 1. By adjusting these parameters, the compatibility of the mentioned conjecture with the inflationary model can be discussed. We determine the further refining swampland dS conjecture is satisfied. when a < 1 1. 0 0 4 8 9 = 0. 9 9 5 1 3 , we can always find a , b and q whose value is larger than 2, viz for q = 2. 4 , we find 0. 9 9 1 8 5 ≤ a < 1 , which we can choose a = 0. 9 9 2 3 5 according to the condition a < 0. 9 9 5 1 3. Also we know b = 1 − a , so we will have 1 − 0. 9 9 2 3 5 = 0. 0 0 7 6 5 > 0. [ABSTRACT FROM AUTHOR]

In this paper, we introduce two new shape functions of wormholes in f (R , T) gravity. Both shape functions are satisfied by various geometric conditions. We will also discuss the different energy conditions and geometric behavior corresponding to each shape function in different states. Finally, we investigate the system's stability with a solution corresponding to the two shape functions. [ABSTRACT FROM AUTHOR]

We study the connected components of the stochastic geometry model on Poisson points which is obtained by connecting points with a probability that depends on their relative position. Equivalently, we investigate the random clusters of the random connection model defined on the points of a Poisson process in d‐dimensional space where the links are added with a particular probability function. We use the thermodynamic relations between free energy, entropy, and internal energy to find the functions of the cluster size distribution in the statistical mechanics of extensive and nonextensive. By comparing these obtained functions with the probability function predicted by Penrose, we provide a suitable approximate probability function. Moreover, we relate this stochastic geometry model to the physics literature by showing how the fluctuations of the thermodynamic quantities of this model correspond to other models when a phase transition (10.1002/mma.6965, 2020) occurs. Also, we obtain the critical point using a new analytical method. [ABSTRACT FROM AUTHOR]

In this paper, we study the Penrose process and the maximum energy extracted from the collision of two particles near the Kerr–Newman black hole with WGC condition. We show that these conditions increase the energy extracted from the black hole. In this process, two particles collide in the ergosphere region, leading to two more scattered particles. The fate of these particles leads to falling into a black hole or escaping to infinity. The WGC condition leads to an increase in the energy of the particles escaping to infinity. We also investigated the amount of energy extracted by particles with different spins from the black hole. These achievements will help identify and study other black holes and spinning particles in astrophysics and make how black holes work more transparent in WGC conditions. [ABSTRACT FROM AUTHOR]

In this paper, we study various cosmological parameters and quantities in scalar–tensor gravity (STG) from inflation and swampland conjecture. Therefore, by selecting different models as power-law, exponential, and logarithmic in the framework of scalar–tensor theory, we obtain potential, tensor-to-scalar ratio, and the scalar spectral index. Next, we examine new constraints and compare the corresponding results with the latest observable data. Here, we take advantage of the obtained results and determine the compatibility or incompatibility of the corresponding model with the swampland conjectures. [ABSTRACT FROM AUTHOR]

In this paper, we want to study warm vector inflation from the framework of a hybrid scenario in the face of refined swampland conjectures. First, we introduce the warm vector inflation structure. Then, we consider a hybrid model and examine inflation in various constant and variable structures of dissipative regimes. We calculate different types of quantities, such as the scalar spectral index ( n s ) and the tensor-to-scalar ratio (r), which are of particular importance in inflationary cosmology. We will call the refined swampland conjectures in the following and use them in this inflationary scenario. So we analyze the behavior of each of these cosmological parameters and swampland conjectures according to the warm vector hybrid inflation scenario by plotting some figures. Finally, we compare the results with the latest observable data, such as Planck. [ABSTRACT FROM AUTHOR]

In this paper, we evaluate a new refined de Sitter (dS) conjecture perspective. This conjecture provides interesting conditions in studying various inflationary models. Therefore, we challenge refined dS conjecture with a general method for analyzing the potentials with the inflectional point near the top ( V ″ = 0). We find the compatible spaces for our inflationary model that lives out of swampland according to the latest observational data such as Planck 2018. [ABSTRACT FROM AUTHOR]

There are two important different mechanisms, the imaginary potential and entropic force, to investigate the dissociation of heavy quarkonia. In this paper, we calculate these two quantities for static and moving quarkonia in the rotating black 3-brane Type IIB supergravity solution dual to N = 4 super Yang–Mills theory on the Coulomb branch (cSYM) at strong coupling. At T ≠ 0 , there are two black hole branches: the large and small black hole branches. We investigate the effects of rotating parameter and rapidity for the static and moving quakonium at the large and small black hole branches. We find both mechanisms have the same results. In the large black hole branch: as T / Λ and β increase the thermal width decreases and so the suppression becomes stronger. In the small black hole branch: increasing T / Λ leads to increasing the thermal width and the quarkonium dissociates harder but β has an opposite effect. [ABSTRACT FROM AUTHOR]

Wormholes are speculative structures linking disparate spacetime points. Their geometry can be obtained by solving Einstein equations with tolerating the violation of null energy conditions (NEC). Recently, many researchers have studied different wormholes according to different criteria, and they achieved remarkable results. In this paper, we investigate a series of exact solutions of the static wormhole with smeared mass source geometry in modified f (R) gravity theories. In fact, we consider the Lorentzian density distribution which is coming from a particle-like source. To be more specific, the modified gravity models we consider here are some power laws. We compute resulting solutions according to the wormhole field equations. We also specify parameters such as the radial pressure and transverse pressure as well as various energy conditions such as NEC, weak energy conditions and strong energy conditions. Finally, by plotting some figures, in addition to identifying the wormhole throat, we describe the results of either the violation or the satisfaction of the energy conditions completely. [ABSTRACT FROM AUTHOR]

As we know, the inflation models have been considered by researchers in various fields of physics such as cosmology and particle physics for explaining early Universe. According to different conditions and conjectures, there are several types of inflation models. In this article, we want to examine a new condition for the inflation models which is known as the swampland criterion. Therefore, we consider f(R) model that includes a polynomial plus a logarithmic term as R + α R 2 + β R n + γ R 2 log γ R . So, by considering the corresponding modified f(R) gravity on the brane, we obtain the modified cosmological parameters such as spectral index, tensor-to-scalar ratio and a number of e-folds. These modified parameters give us the opportunity to test the compatibility of f(R) gravity model with swampland criteria. Finally, by using some figures as well as observable data, we specify the range of modified cosmological parameters. [ABSTRACT FROM AUTHOR]

It has been shown that AdS/CFT correspondence may be realized between some AdS-like cosmological space and CFT living on the boundary. By extending such works we studied the role of R2 term in the corrected action to the thermodynamic quantities, particularly by adding a boundary counterterms to the gravitational action and considering an AdS-like cosmological space. With such HD (higher derivative) terms and metric we calculated the free energy, as a function of N2T4 times 3/2(1 − 1/N2), that is comparable with perturbative result followed from boundary QFT. In fact the difference between the results obtained from AdS-like cosmological space and the results obtained from strong coupling limit of ℵ = 4 SCFT, by taking into account next to leading term in large N expansion, is just a 3/2 factor. Higher derivative term contributions also appear in entropy and energy via the redefinition of gravitation constant. We explicitly identify higher order counterterms effect in energy as a constant term namely E0. This value can be interpreted as the Casimir energy, so that, there is a full and perfect match between QFT and gravitational action when both R2 term and boundary counterterms are considered. So we can claim that our results have assured us that there is a good fit between AdS-like cosmological space and ℵ = 4 SU(N) super Yang-Mills quantum theory. [ABSTRACT FROM AUTHOR]

Purpose: Service organization supply chains provide a context that amplifies the complexity of interorganizational interdependencies and the need to build unique capabilities and innovative solutions, especially when confronted with man-made or natural disasters. Using the lens of complex adaptive systems (CAS), this study aims to investigate the role of absorptive capacity (AC), change management capability and information quality in improving a firm's ability to cope with disasters – disaster immunity (DI). The study uniquely parses absorptive capacity into a three-variable, second-order construct (absorptive human resource management, absorptive complementary knowledge and absorptive infrastructure). Design/methodology/approach: Using data collected from 264 US service firms in a supply chain context, this paper evaluates the research model using the structural equation modeling approach. Findings: The second-order, three-dimensional framework for AC has far superior psychometric properties as compared to the previous unidimensional conceptualizations. Results show that AC influences a firm's DI through change management capability and information quality – two DI enhancing resources. Originality/value: The paper builds on previous conceptual discussions of absorptive capacity as a multidimensional construct by operationalizing AC as a latent variable with three dimensions (above). Moreover, this paper shows that AC, change management capability, information quality and DI are interrelated parts of a CAS. [ABSTRACT FROM AUTHOR]

In this paper, we study a constant-roll inflationary model in the presence of a noncommutative parameter with a homogeneous scalar field minimally coupled to gravity. The specific noncommutative inflation conditions proposed new consequences. On the other hand, we use anisotropic conditions and find new anisotropic constant-roll solutions with respect to noncommutative parameter. Also, we will plot some figures with respect to the specific values of the corresponding parameter and the swampland criteria which is raised from the exact potential obtained from the constant-roll condition. Finally, different of figures lead us to analyze the corresponding results and also show the effect of above mentioned parameter on the inflationary model. [ABSTRACT FROM AUTHOR]

In this paper, we use corrected f (R) gravitational model which is a polynomial function with a logarithmic term. We employ the slow-roll conditions and obtain the number of cosmological parameters. This helps us to verify the swampland conjectures which guarantees validation of low energy quantum field theory. The obtained results show that the corresponding model is consistent with the swampland conjectures. Also, the upper and lower limits of the parameter n are, respectively, 0.15 and 0.0033. Finally, by using scalar spectrum index n s and tensor-to-scalar ratio r relations and comparing with the Planck 2018 data, we obtain the coefficients α , β and γ. Also, the corresponding results are constructed by several figures, literature and also Planck 2018 data. [ABSTRACT FROM AUTHOR]

The quality of ballast materials is an important criterion in railway track maintenance management systems. Although various studies have been made on the characteristics of ballast aggregates and ballast mechanical behaviours, making an optimal decision on the selection of appropriate ballast materials is still a serious challenge in the railway industry. It indicates a need for an integrated ballast quality index which could help to ensure improved cost-effectiveness of track maintenance. In response to this need, the mechanical, physical and environmental properties of the ballast were categorised and weighted based on their level of influences on the ballast overall conditions. Consequently, a ballast quality/condition index was developed as a function of the influencing parameters. To examine the practicability and applicability of the developed method/index, three types of ballast materials were taken from different sources and their quality was evaluated and discussed using the new index. Through illustrating the effectiveness of the new index in evaluation of ballast materials, it was shown that the new index can play a role to allocate an optimal ballast material quality and improve cost-effectiveness of the current maintenance by providing the ability to optimise ballast maintenance planning. [ABSTRACT FROM AUTHOR]

In this paper, first, we will try to introduce the gravitational domain wall as a physical system. In the second step, we also introduce the Hun differential equation as a mathematical tools. We factorize the known Heun's equation as form of operators P + , P − and P 0 . Then we compare the differential equation of gravitational domain wall with corresponding Hun equation. In that case the above-mentioned operators can be obtained for the gravitational system by the comparing process. Finally, we employ such operators and achieve the corresponding symmetry algebra with the usual commutation relation of operators to each other. Here, by having such operators, we investigate the stability of system. [ABSTRACT FROM AUTHOR]

In this paper, we consider the particle on curved graphene space-time. In that case, we calculate the geometric form of potential which is known as Gaussian function. Here, we introduce the metric background which completely corresponds to curved graphene space-times. This metric leads us to obtain the geometry potential and we make the Laplace Beltrami equation in the mentioned metric background. We also rearrange such relation in terms of the second-order equation. By using the known polynomial, we solve the particle equation of motion in graphene background. In that case, we arrive the energy spectrum which has three terms. We take advantage from energy spectrum and investigate the thermal properties of system. The additional terms give us an opportunity to obtain the corrected entropy and free energy. So, we show that the additional term comes from geometry potential. This correction is important for the large scale. Hence, we show that correction term is logarithmic as well as small scale corrections. [ABSTRACT FROM AUTHOR]

In this paper, the thermodynamical properties and the phase transitions of the charged accelerating anti-de Sitter (AdS) black holes are investigated in the framework of the f (R) gravity. By studying the conditions for the phase transitions, it has been shown that the P − V criticality and the van der Waals like phase transitions can be achieved for T ≈ T c . The Joule–Thomson expansion effects are also examined for the charged accelerating AdS black holes of the f (R) gravity. Here, we derive the inversion temperatures as well as the inversion curves. Then, we determine the position of the reverse point for different values of mass M and parameter b for the corresponding black hole. At this point, the Joule–Thompson coefficient is zero. So, in such case, we can say that such point is very important for the finding of cooling–heating regions. Finally, we calculate the ratio of minimum inversion temperature and critical temperature for such black hole. [ABSTRACT FROM AUTHOR]

We use deformation approach and obtain Lagrangian of charged test particle. We show the effect of non-commutative parameters Θ and β on the Lagrangian of a test particle in Horava-Lifshitz background with charge and without charge and see in the case of β = Θ and without charge, the deformed and non-deformed Lagrangian will be the same. In the case of β = Θ and with charge will be the same but the charge or field need some scaling. Finally, results in the case of β ≠ Θ with charge are completely different. It means that we have other components in addition to having a time component of the field. [ABSTRACT FROM AUTHOR]

In this paper, we consider Klein–Gordon particle near Reissner–Nordström black hole. The symmetry of such a background led us to compare the corresponding Laplace equation with the generalized Heun functions. Such relations help us achieve the generalized s l (2) algebra and some suitable results for describing the above-mentioned symmetry. On the other hand, in case of r → r + , which is near the proximity black hole, we obtain the energy spectrum. When we compare the equation of RN background with Laguerre differential equation, we show that the obtained energy spectrum is same as the three-dimensional harmonic oscillator. So, finally we take advantage of harmonic oscillator energy and make suitable partition function. Such function help us to obtain all thermodynamical properties of black hole. Also, the structure of obtained entropy lead us to have some bit and information theory in the RN black hole. [ABSTRACT FROM AUTHOR]

In this paper, we use Bekenstein entropy and study thermodynamic quantities and phase transition for the charged BTZ black hole. Then, we apply the Sharma–Mittal (SM) entropy and calculate some thermodynamic quantities. Here, we note that in case of R ≤ δ , the SM entropy is same as the known corrected entropy. Also, we investigate P − V critically and phase transition of this corrected black hole and show that the critical points of corrected black hole are similar to Van der Waals fluid. We compare phase transition of corrected and uncorrected entropies to each other. Finally, we study the effect of SM entropy on the global and local stability in the extended phase space. Here, we also compare the obtained results of corrected entropy with respect to uncorrected entropy. [ABSTRACT FROM AUTHOR]

Background and Objectives: Enterococci as a part of the normal flora of human gastrointestinal tracts can cause infections in children and adults who have a weaker immune system. The aim of this study was to determine and compare vancomycin, gentamicin, erythromycin and tetracycline resistance in enterococci isolated from Tabriz Children's Hospital. Materials and Methods: In this laboratory study, between May 2016 and May 2017, one hundred enterococci isolates (fifty clinical isolates from variant specimens and fifty stool isolates from different parts of Tabriz Children's Hospital) were collected. After determinig the type, they were tested for their resistance against antibiotics (vancomycin, gentamicin, erythromycin, tetracycline) by disk diffusion. Data analysis was performed using T-test. Results: Out of 50 clinical isolates, 23 (46%) isolates belonged to Enterococcus faecium while 27 (54%) isolates were Enterococcus faecalis. Among 50 stool isolates, 48 (96%) isolates were Enterococcus faecium and 2 (4%) isolates were Enterococcus faecalis. The results also indicated that there was a significant difference between the clinical and stool isolates in regard to vancomycin (p=0.004), but no significant difference was observed between the clinical and stool isolates in regard to the other antibiotics. Conclusion: Considering the results, stool isolates have higher resistance to antibiotics than those of clinical isolates. Increasing antibiotic resistant strains, especially vancomycin among enterococci, is a serious threat to the general public, especially hospitalized patients, and limits the treatment options for patients with nosocomial infections. [ABSTRACT FROM AUTHOR]

The entropic force experienced by a moving quarkonia in a plasma is computed in a hyperscaling violation background by holography approach. In that case, the axis of the moving quarkonia has an arbitrary angle with wind. We use the results for HSV parameters, which are obtained in our paper,1 as appropriate values satisfying condition ImVQQ̄<0. We will show that, in this background, the entropic force of the meson shows a decreasing behavior corresponding to increasing dissociation length. Results of this paper are in agreement with our mentioned work. In addition, we will find diffusion constant in an exact case and by an exact approach2 which satisfies the mentioned condition in there. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the effects of noncommutative phase-space on the quintom cosmological model. In that case, we discuss about some cosmological parameters and show that they depend on the deformation parameters. We find that the noncommutative parameter plays important role which helps to re-arrange the divergency of cosmological constant. We draw time-dependent scale factor and investigate the effect of noncommutative parameters. Finally, we take advantage from noncommutative phase-space and obtain the deformed Lagrangian for the quintom model. In order to discuss some cosmological phenomena as dark energy and inflation, we employ Noether symmetry. [ABSTRACT FROM AUTHOR]

We note that, in extended phase space the cosmological constant is a thermodynamic variable. In this paper, this cosmological constant lead us to consider a black hole as a heat engine. So, here we take advantage from holographic heat engine and study two kind of different black holes. We first investigate a static black hole (Dyonic BH) and consider the necessary condition to have high efficiency. Also we continue our investigation for dynamic black hole (rotating charged black hole) and study the effect of rotating parameter on the thermodynamic efficiency of holographic heat engine. We show that the rotating parameter has a more effective role than electric charge in thermodynamic efficiency. [ABSTRACT FROM AUTHOR]

In this paper, we take cosmological constant as a thermodynamical pressure and its conjugate quantity as a thermodynamical volume. This expression helps us to investigate the phase transition and holographic heat engine. So, in order to have Van der Waals fluid behavior in Horava-Lifshitz (HL) black hole, we modified the solution of such black hole with some cosmology ansatz. Also from holographic heat engine, we obtain Carnot efficiency for the HL black hole. The phase transition of the system lead us to investigate the stability condition for the corresponding black hole. In that case, we show that the stability exist only in special region of black hole. [ABSTRACT FROM AUTHOR]

In this paper, we derive the perturbation and post Markovian perturbation to non-Markovian equation of motion(NMEM) that correspond to coherent and quadrature non-Markovian stochastic Schrödinger equations (SSE). In that case, we derive two perturbation approaches for zero and first orders to the coherent and quadrature NMEM. In order to explain both approaches, we apply two examples of non-Markovian. [ABSTRACT FROM AUTHOR]

In this paper, we consider a deformed AdS background and study the effect of deformation parameter on the pair production rate of the Schwinger effect. The electrostatic potential is important for the pair production in the holographic Schwinger effect. In this paper, we analyze the electrostatic potential in a deformed AdS background and investigate the effect of deformation parameter which may be useful to test the AdS/QCD. In the case of zero temperature, we find that the larger value of the deformation parameter leads to a smaller value of separation length of the test particles on the probe. Also, we find a finite maximum of separation length in the presence of modification parameter. [ABSTRACT FROM AUTHOR]

In this paper, we derive the non-Markovian stochastic equation of motion (SEM) and master equations (MEs) for the open quantum system by using the non-Markovian stochastic Schrödinger equations (SSEs) for the quadrature unraveling in linear and nonlinear cases. The SSEs for quadrature unraveling arise as a special case of a quantum system. Also we derive the Markovian SEM and ME by using linear and nonlinear Itô SSEs for the measurement probabilities. In linear non-Markovian case, we calculate the convolutionless linear quadrature non-Markovian SEM and ME. We take advantage from example and show that corresponding theory. [ABSTRACT FROM AUTHOR]

We investigate interacting ghost dark energy models in higher dimensional cosmology. We attempt to model dark matter within a barotropic fluid with . In this work, we consider four different models based on choosing equation of state (EoS) parameter and interaction term. We confirm that our models agree with observational data. [ABSTRACT FROM AUTHOR]

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In this paper, a new algorithm for solving the vehicle/track dynamic interaction problem is developed, aimed at reducing the computational cost. The algorithm called Advanced Solver Algorithm (ASA) uses the full Newton-Raphson incremental-iterative method in conjunction with the Newmark integration scheme to solve the equilibrium equations of the coupled vehicle/track system in time domain. Considering the track as a beam resting on a viscoelastic foundation and each vehicle as a wagon with ten degrees of freedom, the governing differential equations of motion of the vehicle/track system were derived. The wheel/rail contact was considered as a nonlinear Hertz spring and consequently the vehicle/track nonlinear dynamic interaction problem was solved. A comparison between the results of the ASA and those of the most advanced algorithm available was made to evaluate the efficiency of the ASA. It is confirmed that using the ASA can result in 40-70 % of reduction in computational cost. [ABSTRACT FROM AUTHOR]

In this paper, we consider an inflationary model of gravity with polynomial form plus logarithmic term. We calculate some cosmological parameters and compare our results with the Planck 2015 data. We find that presence of both logarithmic and polynomial corrections is necessary to yield slow-roll condition. Also, we study critical points and stability of the model to find that it is a viable model. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the BTZ black hole in P-V critical point of view. As we know, the BTZ black hole does not have P-V critical behavior. So in this case, we introduce some anstaz that give us the modified BTZ black hole. Finally, we show that this modified BTZ black hole is satisfied by the equation of state of Liquid-gas phase transition. [ABSTRACT FROM AUTHOR]

In this paper, we have considered varying modified Chaplygin gas in case of variable G and Λ. Since varying G and Λ give rises to modified form of field equations and conservation law, we have considered two different toy models. In the first model, the Universe is filled with a phenomenological gas while in the second one, there is the existence of gas and a matter with P = ω( t) ρ. By considering sign changeable interaction between fluids we have analyzed important cosmological parameters such as EoS parameter of the fluids and deceleration parameter q of the models. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the incidence of Enterococcus species and six virulence factors of Enterococcus faecium which were isolated from surface water and wells. Fifteen different water samples, which were used for drinking as well as agricultural irrigation, were collected from nine private wells and surface water from six rivers located at the east of Tehran. The Ent. faecium isolates were tested for their resistance to 10 antibiotics and their virulence factors were detected using multiplex PCR for esp, acm, gelE, asa1, cylA and hyl genes. The most predominant species in 315 isolates were Ent. faecium ( n = 118) followed by Enterococcus galinarom ( n = 110), Enterococcus mundeti ( n = 18), Enterococcus hirea ( n = 37) and Enterococcus casselifelavus ( n = 32). The resistance rates were observed in 41·5, 27·1, 12·7, 6·8 and 1·7% isolates for tetracycline, erythromycin, ampicillin, ciprofloxacin and chloramphenicol respectively. None of the Ent. faecium isolates were resistant to vancomycin, teicoplanin, linezolid, gentamicin and quinuspristin-dalfopristin. Virulence determinant was found in 84·7, 33·9, 16·1 and 2·5% of isolates for acm, asa1, esp, cylA respectively. None of the isolates carried hyl and gelE gene. The presence of virulence factors and antibiotic resistance indicated that water might be an important source of dissemination of virulent enterococci. Significance and Impact of the Study Contamination of drinking or recreational water by human or animal faecal waste is a major public health threat. In this study, we determine the incidence of Enterococcus species and six virulence factors of Enterococcus faecium which were isolated from surface water and wells. Results from this study suggest that the presence of Ent. faecium in natural and well waters was found to be significant in rural areas of Tehran. Resistant to erythromycin among Ent. faecium was relatively high and the incidence of acm and asa1 among our isolates was common overall. [ABSTRACT FROM AUTHOR]

Circadian types are related to many physiological, cognitive, and behavioral variables and, therefore, a need for a questionnaire in Farsi language to assess those preferences has emerged. The present study aimed at exploring psychometric properties of the reduced version of the Persian Morningness- Eveningness Questionnaire ( rMEQ). Participants were 268 students recruited from two different universities. Three questionnaires were used to investigate the additional validity data of the Persian version of the rMEQ: Beck Depression Inventory ( BDI-II), Oxford Happiness Questionnaire ( OHQ), and General Health Questionnaire ( GHQ-12). The correlations between the rMEQ and the three other questionnaires were −0.45, 0.48, −0.41, respectively. Moreover, the factor analysis of the rMEQ resulted in a single-factor solution and the Cronbach's α was 0.71. In sum, the Persian rMEQ seemed to be a reliable and valid instrument to differentiate circadian types. We suggest that future studies focus on test-retest reliability of the rMEQ and an analysis of its unidimensionality with other methods like Item- Response Theory ( IRT). [ABSTRACT FROM AUTHOR]

In this paper, we consider a universe filled with barotropic dark matter and Ricci dark energy in Lyras geometry with varying Λ. We assume two different kinds of interactions between dark matter and dark energy. Then, by using numerical analysis, we investigate some cosmological parameters of the models such as equation of state, Hubble and deceleration parameters. [ABSTRACT FROM AUTHOR]

Streptococcus pneumoniae is an important bacterial pathogen responsible for respiratory infections, bacteraemia, and meningitis remains an important cause of disease and mortality in infants and younger children around the world, with penicillin being considered the drug of choice for the treatment of infections. However, penicillin-resistant S. pneumonia is now becoming endemic worldwide. In this study, a total of 80 pneumococcal isolates were collected from different clinical sources as well as normal flora. These isolates were subjected to antimicrobial susceptibility testing and MIC determination. The penicillin-binding proteins, pbp2b, were amplified by PCR, and they were sequenced. The genetic relationship of the penicillin-resistant isolates was performed by BOX PCR. Overall, 36 pneumococcal (45 %) isolates were found to be resistant to penicillin with different MICs. The majority of them (80 %) were intermediately resistant with MIC of 0.12-1 µg/ml, whereas 20 % of isolates were penicillin resistant with MICs of >2 µg/ml. The results identified seven groups which were based on the amino acid substitutions of pbp2b. Sequencing analysis revealed that the most prevalent mutation was the substitution of Adenine for Thymine at the position 445 which is next to the second PBP2b-conserved motif (SSN). This study indicates that resistance to penicillin appears to be dependent on specific mutations in pbp2b, and the substitution in S620 → T near to the third PBP2b-conserved motif appears to be important in developing highly antibiotic-resistant isolates. Moreover, there was a positive correlation between the mutations in pbp2b gene and MIC. [ABSTRACT FROM AUTHOR]

In this paper, we consider Bianchi type-V spacetime and study a cosmological model of dark energy based on tachyon scalar field. We assumed three different kinds of matter without possibility of interaction with scalar dark energy. Assuming power law Hubble parameter in terms of scale factor we obtain evolution of scalar field, scalar potential and equation of state parameter. [ABSTRACT FROM AUTHOR]

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