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Development of material for agar-based ultrasound brain phantom
Řehořková, Petra ; Smékalová, Monika (advisor) ; Holas, Ondřej (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Mentor: Mgr. Monika Smékalová, Ph.D. Consultant: MUDr. Michael Bartoš Student: Petra Řehořková Title of Thesis: Development of material for agar-based ultrasound brain phantom This thesis is concerned with the development of a material for an agar-based ultrasound phantom that would provide skill acquisition and experience in a manner approximating real surgery. The aim is to formulate and optimize the agar hydrogel preparation procedure, evaluate its acoustic properties and water loss during storage. A dependence was found between the amount of water evaporated during storage (4 weeks at 37 řC) and the glycerol content, which slows down the water loss from the samples in direct proportion. Based on the results, an agar gel (AG) formulation with 1% agar and 60% glycerol was selected for the acoustic properties measurements. During this experiment the microbial stability of AG was confirmed. The results of acoustic parameters measurements were evaluated, namely, speed of the ultrasound, attenuation coefficient and echogenicity of the samples as a function of content of scattering particles Al2O3 and SiC. It was shown that each type of particles affects grayscale value and attenuation coefficient in a...
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Development of material for agar-based ultrasound brain phantom
Řehořková, Petra ; Smékalová, Monika (advisor) ; Holas, Ondřej (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical technology Mentor: Mgr. Monika Smékalová, Ph.D. Consultant: MUDr. Michael Bartoš Student: Petra Řehořková Title of Thesis: Development of material for agar-based ultrasound brain phantom This thesis is concerned with the development of a material for an agar-based ultrasound phantom that would provide skill acquisition and experience in a manner approximating real surgery. The aim is to formulate and optimize the agar hydrogel preparation procedure, evaluate its acoustic properties and water loss during storage. A dependence was found between the amount of water evaporated during storage (4 weeks at 37 řC) and the glycerol content, which slows down the water loss from the samples in direct proportion. Based on the results, an agar gel (AG) formulation with 1% agar and 60% glycerol was selected for the acoustic properties measurements. During this experiment the microbial stability of AG was confirmed. The results of acoustic parameters measurements were evaluated, namely, speed of the ultrasound, attenuation coefficient and echogenicity of the samples as a function of content of scattering particles Al2O3 and SiC. It was shown that each type of particles affects grayscale value and attenuation coefficient in a...
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Development of material for gelatin-based ultrasound brain phantom
Vaclaviková, Andrea ; Smékalová, Monika (advisor) ; Šklubalová, Zdeňka (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Supervisor: Mgr. Monika Smékalová, Ph.D. Consultant: MUDr. Michael Bartoš Student: Andrea Vaclaviková Title od thesis: Development of material for gelatin-based ultrasound brain phantom There are more aspects that have an important role in selection of material for production of single-use ultrasound brain phantom: kind of material, acoustic property, price of materials and their accessibility, simplicity in preparation and its storage requirements, time stability and further. Gelatine as a hydrogel is a proper material for imitation of biological tissues since human body is mostly formed by water what is a prerequisite for acoustic and mechanical quality. Besides that, this natural biopolymer can be available for low costs. The goal was to find suitable combinations in proportion to gelatine, crosslinker, plasticiser, and preservatives in order to create material for ultrasound brain phantom with optimal time of solidification and similar acoustic property of brain in terminal stage. The emphasis was also put on temperature and microbiological stability requirements. For this purpose, there were arranged set of samples of 5%, 7,5% and 10% of gelatine with different proportion of...
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Fast Synchronization of New Nodes in the Fantom Opera Platform
Mlejnek, Matěj ; Homoliak, Ivan (referee) ; Perešíni, Martin (advisor)
Cílem této diplomové práce je prozkoumat aktuální způsoby rychlé synchronizace nových uzlů v rámci jednotlivých blockchain sítí dle závislostí na jednotlivých konsenzech, porovnat jednotlivá řešení mezi sebou, navrhnout možné řešení a naimplementovat novou rychlou synchronizaci pro blockchainovou síť Fantom Opera. Řešení spočívá v tom, že nově připojený uzel se místo do P2P sítě přímo připojí k existujícímu nodu a stáhne si od něj potřebná data pro co nejrychlejší synchronizování se zbytkem sítě.
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Hydrogel fantoms in ultrasonic diagnostic
Chovancová, Aneta ; Sovová, Šárka (referee) ; Hurčíková, Andrea (advisor)
This Bachelor thesis is interested in hydrogel phantoms made from gelatin, agar and agarosa. The effect of food foil on the essential properties of gel matrixes such as drying and moulding has been investigated. These properties were investigated visually and gravimetrically. The speed of prepared gel matrixes was measured using high resolution ultrasonic spectroscopy depending on concentration. In the work, I follow up on the already performed Bachelor thesis [1], where gel matrices were measured in the environment of air and water. My gel matrices are dispensed to the machine's cell in a liquid state. Depending on the material used and the method of use of the food foil, gel matrixes prepared for visual and gravimetric evaluation from agar with a concentration of 3 % and 5 % without foil and with foil on the bottom were found to have a longer shelf life than other samples with the same use of foil. Gel matrixes of all three substances and all concentrations covered with food foil are able to last up to 20 days without massive drying and mould formation. The result of measuring the relative ultrasonic velocity of the hydrogels produced was found to increase the rate of spread of ultrasound for all measured substances as the concentration increased.
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Circularly polarized button antenna on frequency selective surface
Košík, Samuel ; Cupal, Miroslav (referee) ; Kuřátko, David (advisor)
This bachelor thesis is focused on circularly polarized button antenna on frequency selective surface for resonant frequency 5.5 GHz. The concept for this thesis is adopted from article [1]. This published version of the antenna was simulated to verify the validity of the antenna structure behaviour. Several optimalizations have been presented to achieve the best possible results. After all, fantom has been made, as well as the antenna, and used to demonstrate funcionality of the antenna near a human body tissue model. The whole structure with the resonant frequency 5.5 GHz and compact dimensions is primary designed for on-body communication. However, its potentiality is much wider.
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Simulation of ultrasound sequences in contrast mode
Staňková, Jana ; Mézl, Martin (referee) ; Harabiš, Vratislav (advisor)
This bachelor thesis deals with the principle of contrast imaging techniques for ultrasound imaging. In the first part there are described basic principles and characteristics of ultrasound waves for the understanding. It is also focused on ultrasound contrast agents used in contrast enhanced ultrasound imaging. The important part is the description of perfusion models with a focus on obtaining perfusion parametres and analyzing perfusion curves obtained by measuring the ultrasound contrast agent over time. The second part is devoted to designing a program for generating simulated ultrasound images and description of the simulation of 2D ultrasound tomograms.
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Hydrogel phantoms for ultrasound diagnostics
Cerevatova, Kristina ; Smilek, Jiří (referee) ; Pekař, Miloslav (advisor)
This bachelor thesis deals with properties and preparation of hydrogel phantoms used in ultrasound diagnostics. The main object of this work was to get acquainted with the production and problems of phantom models. The theoretical part of the thesis focuses on phantom characterization, the principle of ultrasound, and phantom manufacturing companies. The practical part focuses on production of phantom models in Dansk Fantom Service, and on own production in the laboratory. Then on these phantoms was studied the speed of ultrasound, attenuation, and other physical changes.
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Linear Accelerator Input Beam Data Collection for DIAMOND Calculation Systém Setup
KRÁKORA, Martin
The first chapter of the theoretical part of my bachelor's thesis is focused on the theme of radiotherapy in general as well as to its history. Radiotherapy is a young medical field which treats both malignant and non-malignant diseases by ionizing radiation. The roots of this discipline go back to the beginning of the 20th century, when German physicist Wilhelm Conrad Rontgen discovered X-rays. These rays started to be used in the treatment of tumorous diseases; the first case of tumour elimination by these rays was described in 1896. The second theoretical chapter outlines the types of radiotherapy and their clinical applications. The first type of radiotherapy is curative (radical), which is the primary choice for treatment of tumours, with the aim to eradicate the tumour completely and cure the patient. Another type of radiotherapy is adjuvant. This is a "securing" method, indicated in case of assumption that there are still microscopic tumour remains in the patient's body. There is also neoadjuvant radiotherapy, so-called preoperative. It is applied before the medical procedure when it is necessary to reduce the size of the tumour. Another clinically applied type is radiotherapy with palliative intent. This treatment is indicated to patients whose disease is incurable and serve to remove or alleviate the symptoms. The last type is non-tumorous radiotherapy. This method of treatment is used for non-tumorous diseases and it is always the method of the last resort. The following chapter discusses the theme of radiotherapeutic irradiator. These devices include simulator which simulates the irradiation plan and is very important for planning and control in radiotherapy. Linear accelerators are the most often tools used for irradiation. These accelerators use high-frequency beam of photons or electrons for irradiation. Other devices used in radiotherapy include cobalt and cesium irradiators. The fourth chapter deals with planning in radiotherapy. Irradiation plan, which must be approved by a doctor, is put together in the process of planning. This plan is approved in case when the created combination of irradiation fields achieves the most accurate covering of the target volume by a required dose, and at the same time healthy tissues and organs are spared as much as possible. This chapter also mentions the theme of phantoms that are very important for planning in radiotherapy. Phantoms were also used during the measurement within the practical part of the thesis. The fifth chapter is devoted to irradiation techniques used in radiotherapy. All basic techniques used for irradiation are described here one-field irradiation technique, which is the simplest one, two-field irradiation, i.e. contralateral, convergent or tangential techniques. Also three-field irradiation technique the T and Y techniques, as well as the four-field technique BOX and Crossfire techniques. The most complex techniques include five and more fields where three-dimensional conformational radiotherapy is used. The last chapter describes individual planning systems used at the Department of Oncology of České Budějovice Hospital, with which the objectives of the practical part of the bachelor's thesis were achieved. These planning systems include Mephysto mc2, Diamond and Eclipse programs. Independent measurements were carried out within the practical part of the bachelor's thesis, on the basis of which the following hypothesis was confirmed: "A procedure implemented in compliance with methodology No. 4 can shorten the time of measuring of parameters of ionizing radiation beams from linear accelerator to be entered into the DIAMOND computing system." The aim of the thesis was to get data files for entering the source of ionizing radiation (linear accelerator) into the DIAMOND computing system. This objective was achieved and the respective data files are presented in the chapter of Results (the whole version is attached to this thesis on a CD).
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Design and construction of MR phatoms for MRI
Daňová, Ľudmila ; Odstrčilík, Jan (referee) ; Kudlička, Petr (advisor)
The object of the thesis is the design of the static phantom used in the MRI. It solves the generation of the pictures obtained from the magnetic resonance and its physical principles. The thesis focuses on two types of phantoms - dynamic and static, and especially on phantom used for the LCModel. There is also information about components that will be used for the detection of the spectrums of the selected metabolites.
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