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New Exact Solutions for Generalized (3+1) Shallow Water-Like (SWL) Equation

Abstract

In this study, we use the improved Bernoulli sub-equation function method for exact solutions to the generalized (3+1) shallow water-like (SWL) equation. Some new solutions are successfully constructed. We carried out all the computations and the graphics plot in this paper by Wolfram Mathematica.

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Application of modified wavelet and homotopy perturbation methods to nonlinear oscillation problems

Abstract

In this paper, an accurate and efficient Chebyshev wavelet-based technique is successfully employed to solve the nonlinear oscillation problems. Numerical examples are also provided to illustrate the efficiency and performance of these methods. Homotopy perturbation methods may be viewed as an extension and generalization of the existing methods for solving nonlinear equations. In addition, the use of Chebyshev wavelet is found to be simple, flexible, accurate, efficient and less computational cost. Our analytical results are compared with simulation results and found to be satisfactory.

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Shapley-Folkman-Lyapunov theorem and Asymmetric First price auctions

Abstract

In this paper non-convexity in economics has been revisited. Shapley-Folkman-Lyapunov theorem has been tested with the asymmetric auctions where bidders follow log-concave probability distributions (non-convex preferences). Ten standard statistical distributions have been used to describe the bidders’ behavior. In principle what is been tested is that equilibrium price can be achieved where the sum of large number non-convex sets is convex (approximately), so that optimization is possible. Convexity is thus very important in economics.

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Dynamics of the Modified n-Degree Lorenz System

Abstract

The Lorenz model is one of the most studied dynamical systems. Chaotic dynamics of several modified models of the classical Lorenz system are studied. In this article, a new chaotic model is introduced and studied computationally. By finding the fixed points, the eigenvalues of the Jacobian, and the Lyapunov exponents. Transition from convergence behavior to the periodic behavior (limit cycle) are observed by varying the degree of the system. Also transiting from periodic behavior to the chaotic behavior are seen by changing the degree of the system.

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Important Notes for a Fuzzy Boundary Value Problem

Abstract

In this paper is studied a fuzzy Sturm-Liouville problem with the eigenvalue parameter in the boundary condition. Important notes are given for the problem. Integral equations are found of the problem.

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Adhesion and Colonisation of Microorganisms on Porous TiO2 and TiO2-Silver Biomaterials

Abstract

Bone graft transplantation is one of the most common transplants in the world and there has been a significant increase in the use of biomaterials in this sector. Bone substitutes are widely used in traumatology, orthopaedics, maxillofacial surgery and dentistry. The culturing method was used to determine microorganism ability to attach and form biofilms on originally synthesised porous TiO2 and TiO2Ag ceramics. The aim of this study was to determine and compare the intensity of adhesion and colonisation of Staphylococcus epidermidis, Pseudomonas aeruginosa and Candida albicans on TiO2 and TiO2Ag ceramics. The lowest adhesion and colonisation were on TiO2Ag samples for S. epidermidis and P. aeruginosa.No C. albicans adhesion and colonisation differences were found on TiO2 and TiO2Ag ceramic samples.

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All intra-regular generalized hypersubstitutions of type (2)

Abstract

A generalized hypersubstitution of type τ maps each operation symbol of the type to a term of the type, and can be extended to a mapping defined on the set of all terms of this type. The set of all such generalized hypersubstitutions forms a monoid. An element a of a semigroup S is intra-regular if there is b ∈ S such that a = baab. In this paper, we determine the set of all intra-regular elements of this monoid for type τ = (2).

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Anthropometric Parameters and Biochemical Markers of Military Personnel Under the Influence of High Physical and Psychological Loads

Abstract

Physical fitness, health, and physical endurance are important attributes of persons in military. The purpose of the present study was to assess the changes of anthropometric parameters and of biochemical markers in blood serum for participants of a one-week combat training course (CTC) during which participants had high physical and psychological loads in combination with dietary limitation and sleep deprivation. High physical and psychological loads cause changes in the level of biochemical markers that are indicative of musculoskeletal system dysfunction. The study group included participants (n = 59) of both genders aged 23 to 30 years. Anthropometric parameters (body mass, height, body mass index) were determined. Blood plasma analyses were done before and directly after CTC. Biomarkers like lactate dehydrogenase (LDH), creatine phosphokinase (CPK), alanine amino transferase (ALT) and aspartate amino transferase (AST) were measured. Data were analysed by using SPSS 20. We determined levels of anthropometric parameters before, during and after a combat training course. The body mass decreased during the one-week training course, until the sixth day of combat training course, when the peak of physical and emotional stress was reached. The level of biomarkers lactate dehydrogenase and creatine phosphokinase sharply increased after the combat training course. A high physical load caused changes in biochemical markers, indicating musculoskeletal dysfunction in healthy young persons. The study underlines the importance of checking the health status of military personnel before and after exercises with high physical and psychological loads in order to prevent major health disorders in the combat environment.

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Antiplatelet Resistance in Patients with Atherosclerosis

Abstract

Variable platelet response to aspirin and clopidogrel is a well-known phenomenon in patients with coronary artery disease and ischemic cerebral stroke. The objective of the present study was to evaluate the frequency and possible risk factors of antiplatelet resistance in patients with cerebrovascular and cardiovascular diseases. The VerifyNow system was used to evaluate adenosine-5-diphosphate and platelet P2YI2 receptor function in patients with cerebrovascular and cardiovascular disease, who received dual antiplatelet therapy. Aspirin resistance was defined as aspirin reaction units (ARU) ≥ 550. Clopidogrel resistance was defined as Platelet Reaction Units (PRU) > 230. In the group of cerebrovascular diseases there were 13.2% (n = 27) patients with aspirin and 24.5% (n = 50) with clopidogrel resistance. However, in the cardiovascular group there were 20% (n = 9) aspirin and 11.1% (n = 5) clopidogrel resistant patients. In the cerebrovascular group, aspirin resistant patients had a lower triglyceride level (p = 0.001, r = 0.26) than aspirin sensitive patients. Clopidogrel resistant patients had a significantly higher level of glycated haemoglobin (HbA1C) (p = 0.016, r = 023), triglycerides (p = 0.033, r = 0.16) and lower level of high-density lipoproteins (p = 0.027, r = 0.16) than clopidogrel sensitive patients. In the cardiovascular group, patients who were resistant to aspirin had a significantly higher high-density lipoprotein level (p = 0.038, r = 0.31). No other factors differed significantly between the aspirin or clopidogrel resistant and sensitive patients in the cardiovascular group. Aspirin resistance was more common in patients with cardiovascular disease, and clopidogrel resistance in patients with cerebrovascular disease, although the difference was not significant. Our findings indicate that diabetes mellitus and an elevated level of lipoproteins could be risk factors for aspirin or clopidogrel resistance in patients with cerebrovascular diseases. Further studies should be conducted using larger patient cohorts with balanced groups of patients to investigate clinical aspects of antiplatelet resistance.

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Association of Non-Invasive Markers of Liver Fibrosis with HCV Coinfection and Antiretroviral Therapy in Patients with HIV

Abstract

The aim of this study was to assess the main effects and interaction between viral hepatitis C (HCV) coinfection and antiretroviral therapy (ART) by using a nonparametric ANOVA on direct and indirect markers of liver fibrosis in HIV-infected patients. The sample included 178 HIV patients aged from 23 to 65 (36% females). The following parameters were determined in blood of patients: hyaluronic acid, pro-matrix metalloproteinase-1, alanine aminotransferase, aspartate aminotransferase, and platelet count. The FIB-4 index was also calculated. The nonparametric ANOVA revealed no significant interaction between HCV coinfection and ART. This provides evidence for an independent contribution of each factor on promotion of the pathology. The results also demonstrated that the direct and indirect indicators of liver fibrosis are associated differently with the studied factors. Therefore, a combination of markers should be used for monitoring of liver fibrosis in HIV-infected patients.

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