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Yu. O Moskalenko

охраны. Dubinin, M. Yu., Rykov, D. A. Open desktop GIS: review of the state of the art // Information Bulletin of GIS Association. - 2009. - N 5 (72). - P. 14-21. - Russian : Дубинин М. Ю., Рыков Д. А. Открытые на- стольные ГИС: обзор текущей ситуации. Fesenko, H. V., Kaliuzhna, M. O., Khomenko, S. V. Infl uence of the climatic and topographical factors on distribution of the Black Stork (Ciconia nigra (Linnaeus, 1758)) in Ukraine // Branta. - 2012. - Is. 15. - P. 7-29. - Ukrainian : Фесенко Г. В., Калюжна М. О., Хоменко С. В. Вплив

Open access

O. V. Vasyliuk, O. D. Nekrasova, D. V. Shyriaieva and G. O. Kolomytsev

Abstract

We identified major factors (both direct and indirect), caused by the hostilities in Ukrainian ATO zone that adversely influence local biodiversity and environment. Damaged conservational territories (objects of nature conservation fund) were assessed. One of the most severe factors, the fires were studied using data from Terra MODIS remote sensing, resulting in a model of localization and spatial configuration of fires on natural and agricultural territories in ATO zone during June-September 2014. In that period, 2901 ignitions were registered in ATO zone, exceeding the numbers for previous four years. It was determined that 81 % of all of the ignitions happened on natural steppe and forest areas, 19 % in settlements. Th e fires damaged 18 % of forest area, 23 % of the steppe area and 14 % of arable lands of ATO zone. For two snake species of Red book of Ukraine — eastern Elaphe dione and more widespread Hierophis caspius — it was shown that most of the animals and their biotopes in Luhansk and Donetsk Regions of Ukraine are under threat. Far example, 65–82 % of 108 finds of these Colubridae registered in the eastern Ukraine are located in the ATO zone and near to hostilities. GIS models also showed that more than 50 % of biotopes, suitable for these snakes, are in the ATO zone or near it. Based on world-wide experience and our own observations, we safely assume that the events of 2014 in the ATO territory can possibly cause far-reaching adverse consequences for natural landscapes, local flora and fauna, and the massive local disappearance of plant and animal populations.

Open access

Snejana Tsanova and Georgi Tomov

Morphological Changes in Hard Dental Tissues Prepared by ER:YAG Laser (Litetouch, Syneron), Carisolv and Rotary Instruments. A Scanning Electron Microscopy Evaluation

Aim: This in vitro investigation aimed to study by means of scanning electron microscope the morphological changes in hard dental tissues after using several different methods for caries removal and cavity preparation.

Materials and methods: Twenty freshly extracted human teeth with carious lesions were used in the study. They were assigned to four groups depending on the method used for preparation:

Group 1 - Cavity preparation using Er: YAG laser (LiteTouch, Syneron, Israel).

Group 2 - Chemomechanical preparation using colourless Carisolv gel (MediTeam AB, Savedalen, Sweden).

Group 3 - Mechanical rotary preparation using diamond burs and air turbine.

Group 4 - Mechanical rotary preparation using by steel burs and micromotor.

The preparations were performed strictly according to the manufacturer's instructions for proper use of instruments. The teeth samples were prepared for histological study and investigated by a scanning electron microscope at different magnification; the morphological changes in the tissues were registered and compared.

Results: There were considerable differences in the surface characteristics of the dental tissues when we analysed the photomicrographs of the specimens obtained using scanning electron microscopy (SEM). The surface after laser treatment remained highly retentive with no residual smear layer; the second best results in this respect were registered when teeth were chemomechanically excavated with Carisolv gel. The mechanical methods of cavity preparation resulted in surfaces with a smear layer of dentin without any microretentions.

Conclusion: The scanning electron microscopy of hard dental tissues prepared using steel and diamond burs showed surfaces covered with a thick smear layer that may be relevant to the subsequent bonding of adhesive restorative materials to the prepared cavity. In preparing the surface using a turbine with diamond burs the smear layer was thinner and part of the dentinal tubules orifices were open in the area of water turbulence.

SEM analysis of hard dental tissues prepared with the help of colourless Carisolv gel showed a rough, retentive surface, some of the dentinal tubule lumens obstructed by denaturated collagen and surface contaminants.

The teeth surfaces prepared with Er:YAG laser Lite Touch (Syneron) remained without smear layer and clearly exposed dentinal tubules orifices. The surfaces were highly retentive.