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Metodika pro obrazovou a morfologickou analýzu miniaturních portrétů
Pech, Michal ; Hradilová, Janka ; Hradil, David
The methodology is intended primarily for laboratories and restorers; it describes basic non-invasive methods of image and morphological analysis suitable for the study of miniature painting. Commonly used methods of restoration research designed for the study of easel and panel paintings can also be applied to the study of miniatures; however, their small size, materials, and techniques impose a number of limitations. Traditional invasive methods associated with sampling cannot be used when examining miniatures. The methodology describes how to adapt commonly used methods, such as visible and UV-light imaging, infrared reflectometry and digital radiography, to the study of miniatures. X-ray fluorescence scanning (MA-XRF spectroscopy) is proving to be a particularly important tool for pigment identification and the study of miniature painting techniques, with its ability to produce high-resolution elemental maps. In the future, it can be expected that this still not widely used method, which combines the advantages of image and analytical methods of exploration, will be rapidly developing.
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Bodová neinvazivní analýza miniatur přenosnými a laboratorními nástroji: metodika pro specifické použití ve výzkumu miniaturního malířství
Kočí, Eva ; Bezdička, Petr ; Hradil, David ; Garrappa, Silvia ; Hradilová, Janka ; Pech, Michal
The methodology brings a comprehensive procedure of non-invasive materials analysis of painted miniature artworks, while it is divided into two subsequent parts. In the first part, it describes the use of portable devices for spectroscopic analysis of miniatures, and in the second, it deals with the application of a new methodological procedure for phase/structural materials analysis based on X-ray powder diffraction. The methodology thus includes the following procedures: (i) determination of the elemental composition of the colour layer by the x-ray fluorescence analysis, (ii) identification of binders and other organic compounds using infrared spectroscopy (FT-IR), and finally (iii) phase/mineralogical and structural analysis to describe in more detail the pigments used and processes of their degradation. As part of this last step, the limits of Raman spectroscopy (RS) and the advantages of powder X-ray diffraction and micro-diffraction (XRPD and micro-XRPD) are described, which include greater gentleness to the analysed objects. A very complete and above all non-invasive methodological procedure for the analysis of miniatures is thus offered, which uses the complementarity of individual methods and which can be partly applied already in situ (directly in collection institutions) and partly at specialized workplaces.
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Vliv syntetického progestinu etonogestrelu na sekundární pohlavní znaky a histologii gonád živorodky Wingeovy (Poecilia wingei)
PECH, Michal
Synthetic progestins are steroid hormones, which are not only part of the hormonal contraceptives, but they are also used to treat a number of health problems in human. Due to the widespread use of progestin-based drugs, their residues are being found in wastewaters, from where they also enter into the wastewater treatment plants and surface waters. The aim of this thesis was to assess whether the synthetic progestin etonogestrel affects the secondary sexual characteristics and gonad histology of Endler´s guppy (Poecilia wingei). During the experiment, males and females were separately exposed to 3.2 and 320 ng.l-1 etonogestrel for 34 days. A group of fish reared in pure water (K) and group of fish reared in pure water containing the solvent dimethylsulfoxide (KS) served as controls. At the end of the test, all the fish were photographed to capture any color changes. Then the fish were sacrificed and fixed in 10 % buffered formalin solution for morphometric and histological analysis. Fish samples taken for morphometric analysis were photographed using QuickPHOTO MICRO 2.3 software and individual morphometric parameters were measured on the images taken. Fish sample processing for histological analysis included decalcification, dehydration, and pouring of the samples into paraffin blocks. Then paraffin blocks were cut with the thickness of about 4.5 um, resulting slides were stained with hematoxylin and eosin. Histological changes of the gonads were determined on the histological samples prepared in this way. In females exposed to both concentrations of etonogestrel occurrence of color spots was observed. Color spots are characteristic for male and in females indicate masculinization. In addition, females exposed to 320 ng.l-1 etonogestrel showed a change in anal fin morphometry to a gonopodium-like structure (modified anal fin of males serving as helping copulatory organ), a sign also suggesting masculinization. Furthermore, exposure of etonogestrel in both lower and higher concentration of etonogestrel reduced number of mature oocytes in the ovaries, and their occurrence decreased with increasing concentration. In males exposed to both concentrations of etonogestrel a smaller ratio of the length of 4th ray to the length of 6th ray of gonopodium was found. In addition, at concentration of etonogestrel 320 ng.l-1 a greater ratio of the length of 6th ray to body length and extension of length of 6th ray was observed. Although there were no changes, which would indicate hypermasculinization, these changes could have a negative impact on reproduction, or sexual selection by the female. Etonogestrel exposure had no effect on the normal development of testes, because predominantly mature spermatophores were found in males of all treatment groups. Based on these findings, we can say that etonogestrel, like other progestins, represents a real risk to fish if it occures in aquatic environment at concentrations reaching units of ng.l-1.
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Estimation of risks associated with the occurrence of synthetic thyroid
PECH, Michal
The aim of this work was to provide a comprehensive overview of published findings regarding thyroid, thyroid hormones, their concentrations, stability in the aquatic environment and effect on fish. To determine the consumption of synthetic thyroid hormones in the Czech Republic, the data on the distribution of the drugs, in which they are contained, is analyzed over a period of five years (2011 - 2015). This has provided information about the issued amount of active ingredients i.e. levothyroxine (T4) and liothyronine (T3) for each year. T4 consumption increased over five years, except for 2013, with the highest consumption in 2015 corresponding to 34.6 kg of T4. T3 consumption ranged only in tens of grams before prescribing drugs containing T3 in the Czech Republic was ceased in September 2013. Based on the distribution of synthetic thyroid hormones, an estimate of concentrations that could normally occur in surface water was performed (PECRIVER). Two variants of the calculation were performed. The first variant was based on consumption of synthetic thyroid hormones. The second variant was based on excretion of thyroid hormones (including natural ones) by humans. Each of these variants was counted with the F value, i.e. the rate of removal of the chemical during the WWTP wastewater treatment process, from two different sources. The first source was the study by Svanfelt et al. (2010) where the efficacy of thyroid hormone removal during the WWTP purification process was 66% for T4 (this value was not determined for T3). The second source was EPI Suite software, which calculated the theoretical efficacy of removal of T4 and T3 at WWTP (35.83% for T4 and 5.36% for T3). The resulting concentrations were relatively low in the first variant. The median of the estimated concentrations of thyroid hormones in surface water with the efficacy of removing thyroid hormones during the WWTP purification process, taken from the study by Svanfelt et al. (2010), ranged from 0.6 - 0.7 ng-l-1 for T4. Using the theoretical value of the elimination rate calculated using the EPI Suite program, the median ranged from 1.1 to 1.3 ng-l-1 for T4 and from 0.0007 to 0.0025 ng-l-1 for T3 before it ceased to be used in September 2013. In the second variant, the resulting concentrations were somewhat higher. Median of the environmental concentrations of thyroid hormone with the removal rate taken from the study by Svanfelt et al. (2010) was determined to 1.5 ng-l-1 for T4. With the EPI Suite removal efficacy, the median was determined to 2.9 ng-l-1 for T4 and 0.13 ng-l-1 for T3. Estimated concentrations of thyroid hormones in surface water may currently seem relatively low to have a significant effect on fish, since the lowest thyroid hormone concentration at which any effect was observed ranged in tens of ng-l-1. However, it should be borne in mind that thyroid hormones enter the surface water as a result of incomplete removal during waste water treatment and fish are exposed to these hormones over a long period of time, meaning that even seemingly low concentration may pose a potential risk to aquatic organisms including fish. The fate of these hormones in the environment is therefore to be judged by further studies and toxicological experiments.
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The technique of the introductory exercises to practice jump disciplines
Pech, Michal ; Krátký, Petr (referee) ; Vindušková, Jitka (advisor)
The technique of introductory exercises to practice jump disciplines Thesis objectives: The main goal of the thesis is to discover faults in three jump disciplines (long jump, high jump and pole vault) based on videoanalysis and to suggest ways of their correction these faults. Jumps were performed by Daniel Fuks and Lukáš Lomický, students of first grade FTVS UK. Methods: Videoanalysis and observation of photo sequences were used in this thesis. On base of these photo sequences the fauts of students were observed and then considering of the way of debugging followed. Results: The results shows the most frequent fault were occured in the technique of an introductory exercises to practice pole vault. On the contrary students coped successfully with the technique of the introductory exercises to practice long jump. Key words: technique, long jump, high jump, pole vault, introductory exercises
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Methodology for monitoring and evaluation of light parameters and biological indicators of internal environment depositories and expositions
Juliš, Karel ; Valach, Jaroslav ; Frankl, Jiří ; Štefcová, Petra ; Pech, Michal ; Kotyk, Michael
The methodology provides guidance procedures for monitoring and evaluation of automatically collected lighting parameters and biological indicators of internal environment depositories and expositions. There is specified a methodology, together with description of particular hardware components and software central point, which collects and evaluates the information acquired. The system, as a whole, is designed as a modular and open platform, which allows a wide variety of user modifications and customisation to almost any specific museum collection, repository or exhibition.
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