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Gallay M.,Pavol Jozef Safarik University in Kosice | Lloyd C.D.,Queens University of Belfast | McKinley J.,Queens University of Belfast | Barry L.,Queens University of Belfast
Computers and Geosciences | Year: 2013

This paper compares the applicability of three ground survey methods for modelling terrain: one man electronic tachymetry (TPS), real time kinematic GPS (GPS), and terrestrial laser scanning (TLS). Vertical accuracy of digital terrain models (DTMs) derived from GPS, TLS and airborne laser scanning (ALS) data is assessed. Point elevations acquired by the four methods represent two sections of a mountainous area in Cumbria, England. They were chosen so that the presence of non-terrain features is constrained to the smallest amount. The vertical accuracy of the DTMs was addressed by subtracting each DTM from TPS point elevations. The error was assessed using exploratory measures including statistics, histograms, and normal probability plots. The results showed that the internal measurement accuracy of TPS, GPS, and TLS was below a centimetre. TPS and GPS can be considered equally applicable alternatives for sampling the terrain in areas accessible on foot. The highest DTM vertical accuracy was achieved with GPS data, both on sloped terrain (RMSE 0.16. m) and flat terrain (RMSE 0.02. m). TLS surveying was the most efficient overall but veracity of terrain representation was subject to dense vegetation cover. Therefore, the DTM accuracy was the lowest for the sloped area with dense bracken (RMSE 0.52. m) although it was the second highest on the flat unobscured terrain (RMSE 0.07. m). ALS data represented the sloped terrain more realistically (RMSE 0.23. m) than the TLS. However, due to a systematic bias identified on the flat terrain the DTM accuracy was the lowest (RMSE 0.29. m) which was above the level stated by the data provider. Error distribution models were more closely approximated by normal distribution defined using median and normalized median absolute deviation which supports the use of the robust measures in DEM error modelling and its propagation. © 2012 Elsevier Ltd. Source

Dorko F.,Pavol Jozef Safarik University in Kosice
European journal of histochemistry : EJH | Year: 2012

The aim of this work was to determine the localization of nicotinamide-adenine dinucleotide phosphate-diaphorase (NADPH-d) activity as the marker for synthesis of nitric oxide synthase (NOS) in the rat thymus after the application of retinoid acid (RA) on 1st, 7th, 14th and 21st days of gestation. The given results can build the basis for understanding of the role of NOS in rat thymus. NADPH-d positive cells were represented with dark-blue color and were localized on corticomedullar junction of the thymus. These cells were of different intensity of coloring and were shaped in oval, circle or irregular forms. NADPH-d positive nerve fibers were observed in perivascular topography. They were marked more strongly in the case of control group. The result of application of RA to gravid rats was that the birth weights of newborn rats and their thymuses were smaller, but without statistically significance. Source

Vranova E.,ETH Zurich | Vranova E.,Pavol Jozef Safarik University in Kosice | Coman D.,ETH Zurich | Gruissem W.,ETH Zurich
Annual Review of Plant Biology | Year: 2013

Isoprenoid biosynthesis is essential for all living organisms, and isoprenoids are also of industrial and agricultural interest. All isoprenoids are derived from prenyl diphosphate (prenyl-PP) precursors. Unlike isoprenoid biosynthesis in other living organisms, prenyl-PP, as the precursor of all isoprenoids in plants, is synthesized by two independent pathways: the mevalonate (MVA) pathway in the cytoplasm and the 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway in plastids. This review focuses on progress in our understanding of how the precursors for isoprenoid biosynthesis are synthesized in the two subcellular compartments, how the underlying pathway gene networks are organized and regulated, and how network perturbations impact each pathway and plant development. Because of the wealth of data on isoprenoid biosynthesis, we emphasize research in Arabidopsis thaliana and compare the synthesis of isoprenoid precursor molecules in this model plant with their synthesis in other prokaryotic and eukaryotic organisms. © Copyright ©2013 by Annual Reviews. All rights reserved. Source

Kocurova L.,Pavol Jozef Safarik University in Kosice | Balogh I.S.,College of Nyiregyhaza | Andruch V.,Pavol Jozef Safarik University in Kosice
Journal of Separation Science | Year: 2013

The present article offers a glance at achievements in single-drop microextraction(SDME), with a focus on the two most commonly used modes of this technique: headspace and direct immersion. Factors affecting SDME, such as the pH and ionic strength of the sample solution, the stirring rate, and the extraction time are briefly summarized. The requirements for the acceptor phase and the influence of the sampling temperature are presented. In addition, the potential of the application of microwave and ultrasonic energy in SDME is also discussed. Examples of the application of the headspace and direct immersion modes of SDME are given in a table as additional Supporting Information. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Lazurova I.,Pavol Jozef Safarik University in Kosice | Benhatchi K.,Pavol Jozef Safarik University in Kosice
Polskie Archiwum Medycyny Wewnetrznej | Year: 2012

Autoimmune thyroid diseases (ATD), as the most common organ-specific auto immune disorder, is frequently accompanied by other organ- and nonorgan-specific auto immune diseases. Although the exact pathogenic mechanism of the coexistence of auto immune disorders has not been clearly defined, genetic and environmental factors, immune defects, and hormonal changes, may play a key role in polyautoimmunity. The role of human leukocyte antigen (HLA) haplotypes, HLA-B8 and -DR3, in the overlapping of auto immune disorders was well supported by higher frequency of these haplotypes in primary Sjögren's syndrome (PSS) and ATD. In addition, polymorphisms of the cytotoxic T lymphocytic antigen 4 gene have been reported to be associated with many auto immune disorders especially those coexisting with ATD. Definite noncasual association of ATD has been clearly documented in patients with PSS, rheumatoid arthritis, and systemic lupus erythematosus. Possible association with ATD is also considered in systemic sclerosis and dermatomyositis. Many authors documented a significantly higher prevalence of antinuclear antibodies (ANAs) in ATD patients in comparison with controls; however, the clinical significance of ANAs in this group is still unknown. The presence of other non-organ-specific antibodies has not been convincingly demonstrated. On the other hand, the prevalence of antithyroid antibodies as well as ATD is higher in patients with systemic connective tissue disease compared with the general population. Based on these data, there is no evidence for the utility of ANA testing in patients with ATD, but because of the high prevalence of ATD and antithyroid auto antibodies, it is clinically important to screen patients with auto immune rheumatic disorders for the presence of thyroid auto immunity. Copyright by Medycyna Praktyczna, Kraków 2012. Source

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