Stochastic models have an important role in modeling and analyzing epidemic diseases for small size population. In this article, we study the generation of stochastic models for epidemic disease susceptible-infective-susceptible model. Here, we use the separation variable method to solve partial differential equation and the new developed modified probability generating function (PGF) of a random process to include a random catastrophe to solve the ordinary differential equations generated from partial differential equation. The results show that the probability function is too sensitive to μ, β and γ parameters.Keywords: epidemic diseases; susceptible-infective-susceptible; deterministic model; stochastic model; probability function 1 Deterministic susceptible-infective-susceptible model Figure  shows a deterministic susceptible-infective-susceptible model for an epidemic disease. In this figure, S is the susceptible population, I is the infective population, μ >  is the natural death rate, γ >  is the removal rate which is a constant. Note that S, I ≥  because they represent the number of people. The infection rate, λ, depends on the number of partners per individual per unit time (r > ) and the transmission probability per partner (β > ). In this system, the first susceptible population in class S is going to be infected, then infected population in class I is going to be susceptible again. The following system of ODE's describes this susceptible-infective-susceptibleFigure  illustrates the system (). This system is nonlinear due to the form of λ = βI. Generation stochastic susceptible-infective-susceptible modelIn this section, we present the state of the generation stochastic [-] susceptibleinfective-susceptible model. The stochastic susceptible-infective-susceptible model is similar to the deterministic susceptible-infective-susceptible model, for the deterministic model we can find an exact function but for the stochastic model, we cannot obtain

No abstract

The first-principles study of cubic perovskites SmXO3 (X = Al and Co) for elastic, mechanical and optical properties is done in the framework of density functional theory (DFT). Optimized structural parameters are obtained first to find mechanical and optical properties of the materials. These obtained structural parameters are in accordance with the published data. The cubic elastic parameters C[Formula: see text], C[Formula: see text] and C[Formula: see text] are then calculated by using generalized gradient approximation (GGA) as an exchange correlation functional in Kohn–Sham equations. Poisson’s ratio, shear modulus, Young’s modulus and anisotropic factor are deduced from these elastic parameters. These compounds are found to be elastically anisotropic and SmAlO3 is brittle while SmCoO3 is ductile. Their covalent nature is also discussed by using Poisson’s ratio. In addition, optical properties like absorption coefficient, extinction coefficient, energy loss function, dielectric function, refractive index, reflectivity and optical conductivity are studied. This study predicts that SmAlO3 and SmCoO3 are suitable for optoelectronic devices.

No abstract

BACKGROUND: Inadequate physical activity has adverse health consequences among adolescents. Mental health problem can be developed by lack of physical activity however it is controversial. The current study aimed to examine the association between level of physical activity with depression, anxiety and stress symptoms among adolescents. METHODS: A representative sample of 1747 adolescents (13-14 years) was randomly selected from 6 schools in a south part of Malaysia. Respondents were asked to fill consent form, and questionnaires including Depression Anxiety and Stress Scale-21 and Physical Activity Questionnaire for Adolescents. RESULTS: Majority of respondents (71.9%) was Malay and more than half of the adolescents had low physical activity. About 40% had depression symptoms, followed by anxiety symptoms (65.9%) and stress symptoms (38.5%). Level of physical activity was significantly associated with gender, anxiety and stress (P<0.001). There were no associations with race, religion and depression symptom. CONCLUSIONS: This study provides some evidence among school-going adolescents related to anxiety and stress symptoms and low physical activities. Further studies are needed to show the protection effects of higher physical activity for depression, anxiety and stress symptoms in adolescents.

No abstract

No abstract

Opinion mining is the technique of analyzing the sentiment, behavior, feelings, emotions, and attitudes of customers about a product, topic, comments on social media, etc. Online shopping has revolutionized the way customers do shopping. The customer likes to visit the online store to find their product of interest. It is becoming more difficult for customers to make purchasing decisions solely based on photos and product descriptions. Customer reviews provides a rich source of information to compare products and make purchasing decisions commonly on the basis of other customer reviews. Clients provide comments in the language of their choice, e.g. the people of Pakistan use Roman script based the Urdu language. Normally such comments are free from scripting rules. Hundreds of comments are given on a single product, which may contain noisy comments. Identifying noisy comments and finding the polarity of these comments is an active area of research. Limited research is being carried out on roman Urdu sentiment analysis. In this research paper, we propose a novel approach by using Boolean rules for the identification of the related and non-related comments. Related reviews are those which show the behavior of a customer about a particular product. Lexicons are built for the identification of noise, positive and negative reviews. The precision of the evaluation results is 68%, recall is also 68% and F-measure is 68%. Ṫhe accuracy of the whole evaluation is 60%.