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The radio therapy process planning
Slavíček, Tomáš ; Kolářová, Jana (referee) ; Hrozek, Jan (advisor)
This thesis aims to bring reader to the problems of radiotherapy, to give him an overview of basic principles and methods used to treat patients with cancer by ionizing radiation. The first part is devoted to the physical description of radiation and means of quantification. Interactions of radiation with matter are discussed next following with characterization of radiation effects on living cells and tissues. In the next part there is a description of the devices used in the treatment by ionizing radiation and an explanation of the various acts of patient's preparation from the target localization to irradiation. The final chapter describes created program with a graphical environment, which includes the key elements of commercial planning systems for the creation of the irradiation plan. This program uses real CT images and provides the user a basic idea of creating radiotherapeutic plan. The user has several functions for creating and optimizing the plan. The output of the program is a graphical representation of the spatial distribution of dose in the patient's body.
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Nuclear accidents
Mik, Martin ; Suk, Ladislav (referee) ; Vojáčková, Jitka (advisor)
This thesis is a research dealing with nuclear accidents and disasters in the world and us. The work is divided into several parts. The first part deals with the regulation of nuclear safety in the Czech Republic. The second part describes the international INES scale. The last and largest section deals with the actual accidents and disasters.
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The effects of ionizing radiation on semiconductor devices properties
Yermalayeva, Darya ; Šteffan, Pavel (referee) ; Musil, Vladislav (advisor)
This master’s thesis deals with the problematics of influence of ionizing radiation on semiconductor devices and their properties. The aim of the thesis is to analyze the different types of radiation that can occur in the areas of application of these components. In the second part, the degradation processes are explored, with emphasis on the influence caused by the radiation dose. Also, the displacement damage and SEE effects are described, but just slightly, because they are not part of this work. The third part describes the device design process and harmful effects, that have to be considered during the design phase. In the forth and the fifth parts of this work were done modeling of radiation effects (influence of dose rate, Single-Event Upset and Total Ionizing Dose) in PSpice program and was carried out the possibility of designing a simple dosimeter with silicon diode. In conclusion, the results of the thesis are summarized and evaluated.
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Communication about radiation risks in medicine from the perspective of ethics
KAFKOVÁ, Monika
The diploma thesis deals with communication about radiation risks in medicine from the perspective of ethics. The aim of this work is to evaluate the quality of communication about radiation risks in medicine. Furthermore, it finds out what level of knowledge of ethical bases of communication radiology assistants and patients have. The work consists of a theoretical and a practical part. The theoretical part provides information about ionizing radiation, history of radiology, X-rays. Furthermore, the effects of radiation, principles and methods of radiation protection are described, as well as medical exposure, ethics in the radiation protection system and process ethical values. In the practical part, a survey was conducted focusing on communication about radiation risks in medicine from the point of view of ethics. Questionnaires were distributed to radiodiagnostic departments of selected hospitals. A sample of respondents consisted of 60 radiological assistants and 150 patients. The results of the questionnaire survey are processed into graphs. Based on the evaluation of all questionnaires, most patients are informed about radiation risks depending on the type of examination. Informed consent and verbal expression are among the most common ways of education about radiation risks. The results also show that a large proportion of respondents has not addressed any ethical issues in this context yet, and most radiology assistants have not even received any training in health ethics. Especially among patients, ignorance of some ethical concepts was an obstacle to completing certain questions in the questionnaire.
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The effects of ionizing radiation on semiconductor devices properties
Yermalayeva, Darya ; Šteffan, Pavel (referee) ; Musil, Vladislav (advisor)
This master’s thesis deals with the problematics of influence of ionizing radiation on semiconductor devices and their properties. The aim of the thesis is to analyze the different types of radiation that can occur in the areas of application of these components. In the second part, the degradation processes are explored, with emphasis on the influence caused by the radiation dose. Also, the displacement damage and SEE effects are described, but just slightly, because they are not part of this work. The third part describes the device design process and harmful effects, that have to be considered during the design phase. In the forth and the fifth parts of this work were done modeling of radiation effects (influence of dose rate, Single-Event Upset and Total Ionizing Dose) in PSpice program and was carried out the possibility of designing a simple dosimeter with silicon diode. In conclusion, the results of the thesis are summarized and evaluated.
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The radio therapy process planning
Slavíček, Tomáš ; Kolářová, Jana (referee) ; Hrozek, Jan (advisor)
This thesis aims to bring reader to the problems of radiotherapy, to give him an overview of basic principles and methods used to treat patients with cancer by ionizing radiation. The first part is devoted to the physical description of radiation and means of quantification. Interactions of radiation with matter are discussed next following with characterization of radiation effects on living cells and tissues. In the next part there is a description of the devices used in the treatment by ionizing radiation and an explanation of the various acts of patient's preparation from the target localization to irradiation. The final chapter describes created program with a graphical environment, which includes the key elements of commercial planning systems for the creation of the irradiation plan. This program uses real CT images and provides the user a basic idea of creating radiotherapeutic plan. The user has several functions for creating and optimizing the plan. The output of the program is a graphical representation of the spatial distribution of dose in the patient's body.
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Nuclear accidents
Mik, Martin ; Suk, Ladislav (referee) ; Vojáčková, Jitka (advisor)
This thesis is a research dealing with nuclear accidents and disasters in the world and us. The work is divided into several parts. The first part deals with the regulation of nuclear safety in the Czech Republic. The second part describes the international INES scale. The last and largest section deals with the actual accidents and disasters.
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The feasibility of different biodosimetric methods for dose estimation in case of radiation accidents.
PAVEZKA, Luboš
A deterioration of the coincidental hazards linked to the use of ionizing radiation is currently observed for four reasons. First, the increasing demand for radiation sources in numerous industrial applications (food sterilization, construction, engineering) leads to an increasing likelihood of loss of the sources or abnormal/unsuitable use and storage. Second, advances in medicine generate new protocols and tools that are more efficient but also much more complex to execute, increasing the risk of accidental overexposure. Third, the possibility of a terrorist attack using radiological or nuclear devices has to be taken into account. Finally, recent events in Fukushima (Japan) highlight the risks of exposure in the case of nuclear power plant accidents. All these issues could lead to the accidental exposure of one to several thousand individuals not wearing dosimeters. Thus, it is essential to be able to assess the exposure level of victims. Nowadays, this evaluation is based on clinical diagnosis (mainly irradiation symptoms and hematological variations) supplemented with biological dosimetry andphysical dose reconstruction. Biological dosimetry is especially important when the personal dosimeter is lacking or when the accidental context is unclear. All this information should help the medical staff to deliver appropriate medical care and to manage the long-term medical follow-up, if required. To fulfil this task, the dose estimates has to be timely, exact and conclusively reached in large-scale disasters. In my bachelor thesis, I have focused on the applicability of the various techniques for different scenarios: small- and large-scale exposes to different levels of a radiation that could manage to the urgent radiation syndrome and exposures with lower doses that do not need direct care, but should be followed for evidence of long-term impacts. The principle of biodozimetry is to utilize changes caused in the individual by ionizing radiation to estimate the dose and, if feasible, to predict or reflect the clinically relevant reaction. Optimally, the changes should be specific for ionizing radiation, and the response should be unaffected by prior medical or physiological variations among subjects, including changes that might be caused by the stress and trauma from a radiation event. There are two basic types of biodozimetry with dissimilar and very often complementary characteristics: those based on changes in biological parameters such as gene activation or chromosomal abnormalities and those based on physical changes in tissues. Factors advised comprise: time interval when the assay is feasible biologically, time for sample preparation and analysis, dose finding limit, ease of use, logistical demands, potential efficiency, point-of-care eligibility, and the ability to support patient diagnosis and treatment within a therapeutically relevant time point. The development of of biodozimetry has been mainly encouraged by the needs after a large-scale accident, where it is essential to have a tool or device to identify those individuals who would profit to be brought into the medical care system.
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