Technological Educational Institute of Western Macedonia

About: Technological Educational Institute of Western Macedonia is a(n) based out in . It is known for research contribution in the topic(s): Symplectic geometry & Numerical integration. The organization has 291 authors who have published 522 publication(s) receiving 7682 citation(s). The organization is also known as: TEI of West Macedonia & TEI of Western Macedonia.

Functional properties of carotenoids originating from algae

Abstract: Carotenoids are isoprenoid molecules which are synthesised de novo by photosynthetic plants, fungi and algae and are responsible for the orange, yellow and some red colours of various fruits and vegetables. Carotenoids are lipophilic compounds, some of which act as provitamins A. These compounds can be divided into xanthophylls and carotenes. Many macroalgae and microalgae are rich in carotenoids, where these compounds aid in the absorption of sunlight. Industrially, these carotenoids are used as food pigments (in dairy products, beverages, etc.), as feed additives, in cosmetics and in pharmaceuticals, especially nowadays when there is an increasing demand by consumers for natural products. Production of carotenoids from algae has many advantages compared to other sources; for example, their production is cheap, easy and environmentally friendly; their extraction is easier, with higher yields, and there is no lack of raw materials or limited seasonal variation. Recently, there has been considerable interest in dietary carotenoids with respect to their antioxidant properties and their ability to reduce the incidence of some chronic diseases where free radicals are involved. Possibly, carotenoids protect cells from oxidative stress by quenching singlet oxygen damage with various mechanisms. Therefore, carotenoids derived from algae could be a leading natural resource in the research for potential functional ingredients.

Newton--Cotes formulae for long-time integration

Abstract: The connection between closed Newton-Cotes differential methods and symplectic integrators is considered in this paper. Several one step symplectic integrators have been developed based on symplectic geometry. However, multistep symplectic integrators have seldom been investigated. Zhu et al. (J. Chem. Phys. 104 (1996) 2275) converted open Newton-Cotes differential methods into a multilayer symplectic structure. Also, Chiou and Wu (J. Chem. Phys. 107 (1997) 6894) have written on the construction of multistep symplectic integrators based on the open Newton-Cotes integration methods. In this work we examine the closed Newton-Cotes formulae and we write them as symplectic multilayer structures. We apply the symplectic schemes in order to solve Hamilton's equations of motion which are linear in position and momentum. We observe that the Hamiltonian energy of the system remains almost constant as integration proceeds.

Microalgae: a novel ingredient in nutrition

Abstract: Microalgae are known for centuries, but their commercial large-scale production started a few decades ago. They can be grown in open-culture systems such as lakes or highly controlled close-culture systems, have higher productivity than the traditional crops and can be grown in climatic conditions and regions where other crops cannot be grown, such as desert and coastal areas. The edible microalgae are the green algae (chlorophyta) and the cyanobacteria. Microalgae contain substances of high biological value, such as polyunsaturated fatty acids, proteins, amino acids, pigments, antioxidants, vitamins and minerals. They are promising sources for novel products and applications and they can be used in the diet of humans and animals as natural foods with health benefits. Moreover, they can find use in the protection of the environment, as well as in pharmaceuticals, biofuel production and cosmetics.

New modified Runge-Kutta-Nyström methods for the numerical integration of the Schrödinger equation

Abstract: In this work we construct new Runge-Kutta-Nystrom methods especially designed to integrate exactly the test equation y^''=-w^2y. We modify two existing methods: the Runge-Kutta-Nystrom methods of fifth and sixth order. We apply the new methods to the computation of the eigenvalues of the Schrodinger equation with different potentials such as the harmonic oscillator, the doubly anharmonic oscillator and the exponential potential.

Symplectic integrators for the numerical solution of the Schrödinger equation

Abstract: The solution of the one-dimensional time-independent Schrodinger equation is considered by symplectic integrators. The Schrodinger equation is first transformed into a Hamiltonian canonical equation. The concept of asymptotic symplecticness is introduced and asymptotically symplectic methods of order up to 3 are developed. Numerical results are obtained for the one-dimensional harmonic oscillator, the hydrogen atom and the one dimensional double-well anharmonic oscillator.