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Metastable beta titanium alloys for biomedical use
Preisler, Dalibor ; Stráský, Josef (advisor) ; Janeček, Miloš (referee)
In this work the effect of die-forging and annealing on the mechanical properties and microstructure of biocompatible metastable alloy Ti-35.3Nb-7.3Zr -5.7Ta-0.7O (wt. %) was studied. Light and scanning electron microscopy, microhardness tests and tensile tests were used to study all prepared conditions. As-cast and as-annealed conditions showed chemical inhomogeneities exhibited as dendritic structure, grains with size of hundreds of micrometers and numerous pores having size of units of micrometers. Precipitation of alpha phase particles was negligible in as-annelaed conditions and only grain boundary alpha paticles formed. Die-forged condition showed grain sizes in the wide range of hundreds of micrometers down to micrometers. Both as-annealed and die-forged conditions showed increased microhardness compared to as-cast condition, but there were no significant differences between different annealing conditions. Yield stress of 870 MPa was found for as-cast condition while as-forged condition exhibited even higher yield stress of 1120 MPa. In both conditions, good room-temperature ductility was demonstrated. Due to its high strength, this alloy is perspective for manufacturing of joint implants.
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Bioresorbable polyurethanes with controlled mechanical properties
Letavaj, Emil ; Žídek, Jan (referee) ; Kupka, Vojtěch (advisor)
Presented diploma thesis deals with preparation of bioresorbable polyurethanes (PUR) and their characterization. The theoretical part describes the feedstocks used for the PUR preparation and summarizes the knowledge about PUR used in medical applications. Experimental part presents characterization of bioresorbable PUR films prepared by reactive casting in one step without the use of organic solvents. The absence of solvents represents a great advantage due to their toxicity and subsequent removal from the resulting product. The synthesis of PUR was conducted under an inert atmosphere by polyaddition reaction of hydrophobic poly(e-caprolactone) (PCL) and hydrophilic poly(ethylene glycol) (PEG) with hexamethylene diisocyanate (HDI). Synthesis under an inert atmosphere was necessary due to a side reaction of isocyanate with atmospheric humidity, which causes the formation of porous films instead of continuous ones. Prepared PUR films were characterized for different PCL/PEG ratios and different isocyanate index (ratio of NCO/OH reacted groups). PUR (isocyanate index 1.05) with PCL content 90 wt. % and higher demonstrated tought behavior in mechanical tests. Increase of isocyanate index and decrease of PCL content under 90 wt. % caused fragile sample behavior. The reason of such behavior was the different ability of PCL to crystallize in the structure of the polyurethane network. Increasing the PEG content has improved the ability of PUR films to absorb water and enhanced the rate of hydrolytic degradation. By adjusting the PCL/PEG ratio and the amount of isocyanate, solvent free bioresorbable PUR with suitable mechanical (flexibility, toughness) and physical properties (swelling, degradation) can be obtained. Prepared PUR films could be used in biomedicine e.g. as vascular grafts.
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Use of cell phone in liquids analysis
Křístek, Tomáš ; Sekora, Jiří (referee) ; Čmiel, Vratislav (advisor)
Technological development, broad availability and ubiquity of mobile phones made it possible in recent years to start a progression leading to the integration of mobile phones into biomedical analytical methods, the development of telemedicine and mobile personal health applications. This paper deals with the literature review of the mobile phone usage in biomedicine, with emphasis on the methods of optical analysis and technical solutions using 3D printing technology. It provides a draft and practical implementation of salivary cortiol level measuring system using a mobile phone, ELISA analytical methods, 3D printing technology and a set of custom Matlab functions connected with Matlab Mobile application and Mathworks Cloud. Also provides critical evaluation of results and method possibilities, and presents set of proposals and findings for quality of measurment optimization.
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Plasma for biomedical and envornmental applictions
MAROUŠEK, Rostislav
This diplom theses is concerned with the possibilities of using non-thermal plasma in biomedical and enviromentally friendly applications. The theoretical part is drawn up as research overview of the current knowledge from the stated issue. The practical part is focused on the modification of nanofibres by deposition of TiOx layers.
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Use of cell phone in liquids analysis
Křístek, Tomáš ; Sekora, Jiří (referee) ; Čmiel, Vratislav (advisor)
Technological development, broad availability and ubiquity of mobile phones made it possible in recent years to start a progression leading to the integration of mobile phones into biomedical analytical methods, the development of telemedicine and mobile personal health applications. This paper deals with the literature review of the mobile phone usage in biomedicine, with emphasis on the methods of optical analysis and technical solutions using 3D printing technology. It provides a draft and practical implementation of salivary cortiol level measuring system using a mobile phone, ELISA analytical methods, 3D printing technology and a set of custom Matlab functions connected with Matlab Mobile application and Mathworks Cloud. Also provides critical evaluation of results and method possibilities, and presents set of proposals and findings for quality of measurment optimization.
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Application of clustering methods for processing of biomedical data
Rozinek, Michal ; Gazárek, Jiří (referee) ; Havlíček, Martin (advisor)
The goal of this study is to learn about methods in object classification in medicine and find out what are these methods about. Focusing on functionality and reliability of these methods whith datafile from the medicine compartment after making the algorithm in MATLAB. In form of siple tests, put the touch everyone of classification procedure and find out in which they excel and in which they lags. The choice of input data parametres is very important, this will be tested and noted in conclusions.
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Lanthanocene Catalysts for Synthesis of Polymers Applicable in Medicine
Slanina, Ondřej ; Kábelová, Božena (referee) ; Richtera, Lukáš (advisor)
The theoretic part of the thesis focuses on materials used in medicine. The metallic, ceramic, glass-ceramic and polymer materials are systematically described. The biocompatibility of the materials and possible threads of their usage for manufacturing of medicinal devices and implants are emphasized in the discussion. The work is focused especially on polymer materials. Different types of polymerizations are summarized with the accent on the preparation of biodegradable materials. In the practical part the synthesis of two organometallic bis(pentamethylcyclopentadienyl) sandwich complexes with holmium and gadolinium as a central atom designed for preparation of materials suitable for biomedicine is proposed.
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Computer simulations of plasma discharge for biomedical and environmental applications
ERHART, Jaroslav
This diploma thesis is aimed to the possibilities of using low-temperature plasma in various fields of science, research and production with the main focus is given to applications in medicine and environmental applications. In the practical part is presented design a computer model for simulation of the plasma behavior in the above areas. This model is a hybrid type and as a working gas is used oxygen.
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