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Comparative Anatomical and Morphological Study of Three Populations of Salvia aethiopis L. Growing in the Southern Balkhash Region

Nurmahanova Akmaral, Ibisheva Nazerke, Kurbatova Natalia, Atabayeva Saule, Seilkhan Ainur, Tynybekov Bekzat, Abidkulova Karimi, Childibaeva Assel, Akhmetova Aigul, Sadyrova Gulbanu

Journal of Ecological Engineering

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2023

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Vol. 24, nr 9

27--38

EN

The manuscript presents the results of morpho-anatomical structure of vegetative organs of Salvia aethiopis L. S. aethiopis L. is a promising medicinal plant of flora of Kazakhstan, which is able to grow under certain soil and climatic conditions. According to its anatomical and morphological features, S. aethiopis L. is a drought-resistant plant that does not tolerate excess moisture. The aim of the study was to investigate the morpho-anatomical structure of S.aethiopis L. plants growing in three different populations of the South Balkhash region of the country. As a result of the study of the morpho-anatomical structure of vegetative organs of the studied plants, the following features of xeromorphic structure of S.aethiopis L. were noted: strong pubescence of all above-ground parts of plants by simple, globular and glandular hairs, well expressed cuticle with small spinules, presence of cuticular thickening of guard cells, large number of stomatal apparatus on lower epidermis. A comparative analysis of the structure of plants of three different populations showed that in the stem of plants of population № 1 the primary cortex and the diameter of the central cylinder are more pronounced in comparison with plants growing in populations № 2 and № 3, which is due to the growing conditions of these populations. In plants of population № 1, an increase in the thickness of the leaf blade as well as inclusions of essential oils, which are localized in single or paired essential oil passages, were noted. In plants of populations № 1 and № 2, the more essential oil passages were observed. The studied plants of population № 1 have the most pronounced thickness of the primary bark than plants of populations № 2 and № 3. The revealed changes in the morpho-anatomical structure of plants are associated with the influence of various environmental and anthropogenic factors depending on the location of the studied plants.

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Fractal model of transdermal drug delivery

Walicka A., Iwanowska-Chomiak B.

International Journal of Applied Mechanics and Engineering

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2018

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Vol. 23, no. 4

989--1004

EN

Skin, separating the vital organs of a human body, is a desirable route for drug delivery. However, the intact skin is normally permeable only for drug molecules with a low molecular weight. The stratum corneum (SC), being the outermost layer of the skin and the epidermis being the second – more permeable – layer of the skin, play an essential function in transdermal drug delivery. Physical and chemical methods of skin poration are used to enhance transdermal drug delivery. Each poration leads to an irregular system of pores which are connected with a system of micro-capillaries passing through the epidermis. Both the systems by their irregularity form a fractal porous matrix. Drugs administrated by this matrix can be either suspensions and solutions or creams and gels, therefore they have to be modelled as non-Newtonian fluids. To analyse the fluid flow through the porous matrix the model of the epidermis is assumed as gobbet-andmortar with the tortuous mortar of variable thickness and after transition from the mortar to the tube one considered classical and fractal capillary flows of selected non-Newtonian fluids. Fractal expressions for the flow rate, velocity and permeability of fluids flow in a porous matrix are derived based on the fractal properties of the epidermis and capillary model. Each parameter in the proposed expressions does not contain any empirical constant and has a clear physical meaning and the proposed fractal models relate the flow properties of considered fluids with the structural parameters of the epidermis as a porous medium. The presented analytical expressions will help understand some of the physical principles of transdermal drug delivery.

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T-cell proliferation on immunopathogenic mechanism of psoriasis: a control based theoretical approach

Datta A., Roy P. K.

Control and Cybernetics

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2013

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Vol. 42, no. 2

365--386

EN

Psoriasis vulgaris is a common, worldwide autoimmune skin disorder characterized by T-cells mediated hyperproliferation of keratinocytes. The feature of T-cells arbitrated psoriatic lesions is the epidermal infiltration of oligoclonal CD8+ T-cells and also of CD4+ T-cells in the dermis. Psoriatic scratches are identified by red and enlarged lesions along with silver whitish scales. In this article, we propose a mathematical model for psoriasis, involving a set of differential equations, concerning T-cells, dendritic cells and epidermal keratinocytes. We introduce T-cell proliferation in the system, where T-cells are generated through expansion of accessible CD4+ T-cells from precursors. We are interested in observing how the cell biological system develops through T-cell proliferation in presence of control with respect to T-cells and keratinocytes. We study the model in both implicit and explicit ways and measure the effect of drug on the system through impulsive drug therapy.

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Estimation of epidermis and dermis thicknesses on the basis of skin surface temperature

Majchrzak E., Jasiński M.

Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej

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2006

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Vol. 5, nr 1

124-133

EN

Heat transfer in the skin tissue is treated as a multi-layer domain in which one can distinguish the epidermis, dermis and subcutaneous region is described by the system of Pennes equations and adequate boundary, initial and geometrical conditions. Many of the parameters used in the mathematical model are difficult to measure, e.g. epidermis or dermis thickness. In the paper the numerical algorithm of these geometrical parameters identification is presented in which the knowledge of skin surface temperature is assumed.