1,166 research outputs found
Mathematical Modeling of the Neuronal Processes in Sugar Addiction
It has already been demonstrated that the body responds to enhanced intake of sugar and is conducive to a natural form of addiction. There are substantial neurochemical changes in the brain (especially dopamine and acetylcholine systems) similar to other addictive drugs. A mathematical model comprised by a system of delayed leaky integrate-and-re equations is established to simulate the effects of sugar on a reward-circuitry. Simulations with Neuron suggest agreement with the neurobiological hypotheses of hyperactivity of neural systems due to binge sugar intake
Application of the Extended G\u27/G-expansion Method to the Improved Eckhaus Equation
In this paper, the extended (G\u27/G)-expansion method is used to seek more general exact solutions of the improved Eckhaus equation and the (2+1)-dimensional improved Eckhaus equation. As a result, hyperbolic function solutions, trigonometric function solutions and rational function solutions with free parameters are obtained. When the parameters are taken as special values the solitary wave solutions are also derived from the traveling wave solutions. Moreover, it is shown that the proposed method is direct, effective and can be used for many other nonlinear evolution equations in mathematical physics
Effect of Organizational Culture on Organizational Health
The main objective of the current study is to investigate the effects of organizational culture on organizational health. Modern organizations are in a very intense competitive conditions and in order to survive, they need parameters which guarantee their survival. Therefore, the current study will investigate the significance of culture in this regard. Municipalities as one of the organizations providing urban services are in a position where it is possible to lose their impact due to the activities of other organizations. Accordingly, the statistical population selected for this study includes all the employees in Tehran Municipality. In order to gather the required data, after determining the sample size as 384 participants using Krejcie and Morgan table, standard questionnaire of Denison for culture (2000) and organizational health (2008) were used. The current study is a quantitative one carried out as a descriptive survey. The validity and reliability of the study are confirmed using appropriate methods. Finally, in order to test the hypotheses of the study, various descriptive and inferential statistical tests were used. It was found out that the organizational survival of Municipality was affected by various cultural parameters, among which compatibility had the highest impact
Two Reliable Methods for Solving the Modified Improved Kadomtsev-Petviashvili Equation
In this paper, the tanh-coth method and the extended (G\u27/G)-expansion method are used to construct exact solutions of the nonlinear Modified Improved Kadomtsev-Petviashvili (MIKP) equation. These methods transform nonlinear partial differential equation to ordinary differential equation and can be applied to nonintegrable equation as well as integrable ones. It has been shown that the two methods are direct, effective and can be used for many other nonlinear evolution equations in mathematical physics
Application of Reduced Differential Transform Method for Solving Two-dimensional Volterra Integral Equations of the Second Kind
In this paper, we propose new theorems of the reduced differential transform method (RDTM) for solving a class of two-dimensional linear and nonlinear Volterra integral equations (VIEs) of the second kind. The advantage of this method is its simplicity in using. It solves the equations straightforward and directly without using perturbation, Adomian’s polynomial, linearization or any other transformation and gives the solution as convergent power series with simply determinable components. Also, six examples and numerical results are provided so as to validate the reliability and efficiency of the method
Analysis of and vertices in three-point sum rules
In this study, the coupling constant of and
vertices were determined within the three-point Quantum chromodynamics sum
rules method with and without consideration of the symmetry. The
coupling constants were calculated for off-shell charm and K cases.
Considering the non-perturbative effect of the correlation function, as the
most important contribution, the quark-quark, quark-gluon, and gluon-gluon
condensate corrections were estimated and were compared with other predictive
methods.Comment: 12 pages, 5 figure
A STUDY OF HYDATID CYST CASES IN IRAN, A SYSTEMATIC REVIEW
Hydatid cyst is an infectious disease common between humans and animals which is spread worldwide and has been known to humans since old times. Different accounts have been presented on the individual characteristics of people suffering from hydatid cyst, clinical course, different treatment and diagnosis methods, and its recurrence. The hydatid cyst infection exits in various parts of the world, and Iran is on the endemic belt of the disease, in a way that different rates have been reported in different studies. Depending on climate conditions, social customs, nutritional status, and the amount of contact with canidae animals, incidence rates of up to 10 have been reported in human populations for these diseases. The present research is a systematic review study. In order to find the studies conducted in Iran, the articles in national and international journals and dissertations available on Magiran, Iranmedex, SID, Google-scholar, and PubMed databases were used, and more than 100 articles were found, among which 14 articles related to the topic that met the criteria for entering the study were investigated. The data collected were analyzed by SPSS version 18 through using descriptive-analytical statistics and chi-squared statistical test (X-2 test). The results of the study showed that infection rate in the liver of cows to hydatid cyst is 62, while lung infection in native and hybrid breeds in the city of Baneh is 7.75. In rural area of Tehran, 437 person, 276 women and 161 men, in the age range of 4-76 years of age were studied, and one person was positive and seven persons were suspected to the disease. The results of the present study showed that, although the infection rate of hydatid cyst in urban and developed parts of Iran is at an acceptable and satisfactory level, the statistics in lesser-developed areas is endemic and alarming and deserves paying more attention and developing organized plans to control the disease
An Empirical Ultra Wideband Channel Model for Indoor Laboratory Environments
Channel measurement and modeling is an important issue when designing ultra wideband (UWB) communication systems. In this paper, the results of some UWB time-domain propagation measurements performed in modern laboratory (Lab) environments are presented. The Labs are equipped with many electronic and measurement devices which make them different from other indoor locations like office and residential environments. The measurements have been performed for both line of sight (LOS) and non-LOS (NLOS) scenarios. The measurement results are used to investigate large-scale channel characteristics and temporal dispersion parameters. The clustering Saleh- Valenzuela (S-V) channel impulse response (CIR) parameters are investigated based on the measurement data. The small-scale amplitude fading statistics are also studied in the environment. Then, an empirical model is presented for UWB signal transmission in the Lab environment based on the obtained results
Exact Solutions of the Generalized Benjamin Equation and (3 + 1)- Dimensional Gkp Equation by the Extended Tanh Method
In this paper, the extended tanh method is used to construct exact solutions of the generalized Benjamin and (3 + 1)-dimensional gKP equation. This method is shown to be an efficient method for obtaining exact solutions of nonlinear partial differential equations. It can be applied to nonintegrable equations as well as to integrable ones
Further Refining Swampland dS Conjecture in Mimetic f(G) Gravity
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
and in terms of and , 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 and are not
, 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 , , and
. 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 , we can always find , and whose value is
larger than 2, viz for , we find , which we can
choose according to the condition . Also we know
, so we will have .Comment: 25 pages, 5 figures. Accepted for publication in International
Journal of Modern Physics D (This work is dedicated to the memory of Prof
Farhad Darabi
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