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Detection of heavy metals in hard tissues by laser-induced breakdown spectroscopy
Konečná, Anna ; Novotný, Karel (referee) ; Pořízka, Pavel (advisor)
This master thesis deals with the detection of heavy metals bioaccumulated in hard tissues by laser-induced breakdown spectroscopy (LIBS). As model samples, murine mandibles and femurs of animals exposed to lead oxide or cadmium oxide nanoparticles were used. The exposure of animals lasted for 6 or 7 weeks. Control group of animals was exposed only to air for a reference. The distribution of biogenic elements and contaminants was determined by mapping the samples' surface using LIBS with a spatial resolution of 30 and 100 µm. The second part of the work focused on the possibility of using the method LIBS for quantitative analysis. Samples of hydroxyapatite standards were prepared as reference material. By their analysis a calibration curve was constructed, and the limits of detection and quantification were determined. Furthermore, a model for prediction of heavy metal concentration by calculation from the calibration curve was presented.
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Optimizing experimental parameters for LIBS analysis of hard tissues
Fazlić, Aida ; Kuchynka,, Michaela (referee) ; Pořízka, Pavel (advisor)
Tato diplomová práce se zaměřuje na detekci a analýzu těžkých kovů, zejména olova (Pb), v tvrdých tkáních pomocí hydroxyapatitových standardů a spektroskopie laserem buzeného plazmatu (LIBS). Studie využívala různé vlnové délky laseru 1064 nm, 532 nm a 266 nm, stejně jako různé konfigurace laseru, včetně jednopulzní (SP, z angl. single-pulse) LIBS a dvojpulzní (DP, z angl. double-pulse) LIBS v ortogonálním a kolineárním uspořádání. Byla provedena optimalizace parametrů laseru, jako jsou vlnová délka, defokus, doba zpoždění, mezipulzní doba zpoždění a energie. Poměr signál-ke-šumu (SBR), limit detekce a rozlišení odpovídající průměru ablačního kráteru sloužily jako základní parametry pro určení optimální kombinace parametrů. Výsledky této studie poskytují důležité poznatky o optimálních parametrech LIBS pro detekci a analýzu těžkých kovů v tvrdých tkáních, což může mít potenciálně významné dopady pro lékařský výzkum.
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Detection of heavy metals in hard tissues by laser-induced breakdown spectroscopy
Konečná, Anna ; Novotný, Karel (referee) ; Pořízka, Pavel (advisor)
This master thesis deals with the detection of heavy metals bioaccumulated in hard tissues by laser-induced breakdown spectroscopy (LIBS). As model samples, murine mandibles and femurs of animals exposed to lead oxide or cadmium oxide nanoparticles were used. The exposure of animals lasted for 6 or 7 weeks. Control group of animals was exposed only to air for a reference. The distribution of biogenic elements and contaminants was determined by mapping the samples' surface using LIBS with a spatial resolution of 30 and 100 µm. The second part of the work focused on the possibility of using the method LIBS for quantitative analysis. Samples of hydroxyapatite standards were prepared as reference material. By their analysis a calibration curve was constructed, and the limits of detection and quantification were determined. Furthermore, a model for prediction of heavy metal concentration by calculation from the calibration curve was presented.
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Monitoring of the relationship between the asymmetry of facial skeleton and the soft tissues based on computed tomography
Skryjová, Zuzana ; Velemínská, Jana (advisor) ; Bigoni, Lucie (referee)
The human face is not perfectly symmetrical, slight asymmetries commonly occur in every individual across all populations. The aim of the work was to monitor the asymmetry on the entire surface of the soft and hard tissues of the heads of individuals with respect to age and sexual dimorphism. The follow-up goal was then to evaluate the difference in asymmetry between the tissues. The material for the work was a transverse set of CT images of the adult Czech population in the age range of 21-84 years. Individuals were divided according to gender into 50 men and 48 women and according to age into groups up to 39 years, 40-59 years and over 60 years. Geometric morphometry methods (CPD - DCA, asymmetry analysis, per vertex T-test, superprojection methods) were used for data analysis. The results were visualized using color maps and significance maps that show asymmetry and statistical significance. The variability of the file was analyzed by principal component analysis. The results of the evaluation of hard tissues showed a right protrusion on the anterior and lateral surfaces of the skull, in both men and women at all age intervals. This asymmetry was statistically very significant, in contrast to the posterior region, which was evaluated protrusion on the left side and had lower p-value. On the soft...
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