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Automatic sleep scoring using polysomnographic data
Kříženecká, Tereza ; Potočňák, Tomáš (referee) ; Ronzhina, Marina (advisor)
The thesis is focused on automatic classification of polysomnographic signals based on various parameters in time and frequency domain. The parameters are acquired from 30 seconds long segments of EEG, EMG and EOG signals recorded during different sleep stages. The parameters used for automatic classification of sleep stages are selected according to statistical analysis. Classification is performed using the SVM method and evaluation of the success of the classification is done using sensitivity, specificity and percentage success. Classification method was implemented using Matlab.
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Fingerprint biometry
Smékal, Ondřej ; Drahanský, Martin (referee) ; Fedra, Petr (advisor)
Algorithms designed for identification and verification persons by fingerprints recognition are spread and used as in forensics aplications as in private sector for a long time. The aim of this thesis is to make us aquainted with various aplicated mathematic models of fingerprint processing in digital way. Second task is the presentation algorithmic solution of chosen subject identification procedure by force of Fingerprint matching. Algorithm is solid in the development environment platform Matlab.
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Atrial fibrillation detection using time-domain methods
Sámel, Maroš ; Ronzhina, Marina (referee) ; Janoušek, Oto (advisor)
The purpose of this work is to get better understanding of the problems of atrial fibrillation followed by the processing methods for detection of atrial fibrillation based on an analysis of the ventricular rhythm. Methods that are described: method of medians, methods based on histograms (using coefficient of variation and density histograms of RR and RR intervals), method using RdR map, method using complexity of RR intervals and methods based on a statistical framework by Gaussian distribution and Laplace function The practical part of this work is focused on comparing these methods and selecting the best one – method of medians is the chosen one. This is followed by implementation of this method in the Matlab and testing it on the real data from a selected database. In the end, the detection ability of our method is evaluated and compared with the thoeretical detection abilities of the other methods. Our algorithm for detection of atrial fibrillations, based on the median method, achieved excellent results with the highest value of specificity obtained at 93,976%, sensitivity at 89,182% and AUC (area under the curve) at 0,973.
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Scoring system for sputum evaluation assessing specificity and sensitivity
Fidra, Dominika ; Trnková, Ivana (advisor) ; Maláska, Jan (referee)
The aim of this diploma thesis is to create a scoring system in sputum evaluation for general nurses in the intensive care unit. It is conceived as a diagnostic study that assesses the ability of the scoring system to accurately determine the ongoing condition - an infectious inflammatory disease. The collected biological material was compared with the gold standard - microbiology, by two independent persons. The result of the diagnostic study is a verified scoring system, where the color, consistency, admixtures and odor of the biological material of sputum are described for individual point evaluations. The main parameters of the diagnostic test - sensitivity, specificity and predictive value (positive and negative) - were used to verify the scoring system. For normal and pathological values, cut-off values were determined, according to which the value of sensitivity and specificity changed. By plotting the values on a graph and creating a ROC curve, it was found that with a cut off value of 1 and 2 for the first evaluator, the resulting area under the curve (AUC)=0.75. The result represents the scoring system according to the first evaluator as a good and effective test. The research was carried out at the anesthesiology and resuscitation clinic at the University Hospital of Kralovske Vinohrady...
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Photobiont plurality in lichen thalli
Dědková, Kamila ; Steinová, Jana (advisor) ; Vančurová, Lucie (referee)
Photobiont plurality refers to the presence of multiple photobionts within a single lichen thallus. This phenomenon was described at the end of the last century but has received deeper attention in the last decade. The available literature on this topic is limited. This bachelor thesis summarizes all the important findings published on plurality to date. The most common photobionts coexisting in a thallus are algae of the genus Trebouxia, but other algae and cyanobacteria more or less phylogenetically related may also coexist together. Thallus with multiple photobionts is formed either at the beginning by the association of hyphae with several photobionts at once (horizontal transport) or by the acquisition of additional photobionts during life (vertical transport). The most important factors affecting the cooccurrence of multiple photobionts in a single thallus are probably the specificity and selectivity of mycobionts and local environmental conditions. The plurality of photobionts has been found in more than fifty lichen species. Many important findings have been described in a model lichen Ramalina farinacea. Its coexisting photobionts differ in responses to several environmental, mostly stress conditions, suggesting that the presence of multiple photobionts in a thallus may provide an...
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Image fusion within prostate biopsy
ŽŮČEK, David
This study deals with the use of image fusion within prostate biopsy, which is a method used for several decades, which serves to accurately capture pathological findings in the prostate, primarily prostate cancer. The combination of imaging modalities, which are magnetic resonance and intracavitary ultrasonography, is used to guide the biopsy. The aim of the study was to study the unusual situation where one and the same radiological team performs both procedures at the same time. Procedures from which the prostate biopsy methodology guided by image fusion is formed. Subsequently, we established a hypothesis that specific benefits can be found when the same doctor and radiology assistant perform both procedures. Procedures which consists of image fusion of magnetic resonance imaging and intracavitary ultrasonography, which guide the prostate biopsy of the same patient. The methodology of the theoretical part was the study of mostly foreign professional medical articles and literature and the subsequent use of the information to clarify the described method. In the practical part, the output data of physical examination of 59 patients were processed with the use of ROC analysis and then compared with two foreign studies to verify the established hypothesis. The data were provided by Mr. MUDr. Zdeněk Chudáček Ph.D. The results of the ROC analysis and its comparison with foreign studies confirmed the hypothesis, and therefore the presence of specific advantages of the studied unusual situation of performing a prostate biopsy in the way determined at the beginning of this study. The results of this study will be used in a broader journal publication, which aims to bring the issue of this study to the professional radiological public.
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Let's meet in the littoral: Diversity of symbiosis in the Verrucariaceae lichens
Schmidtová, Jana ; Škaloud, Pavel (advisor) ; Peksa, Ondřej (referee)
Lichens are organisms formed by several symbiotic partners, most importantly a fungus (mycobiont) and an alga or cyanobacteria (photobiont). Although most lichens are terrestrial, some can be found also in aquatic environments. Black crustose lichens from the family Verrucariaceae (Verrucariales, Eurotiomycetes, Ascomycota) were able to adapt to this environment very well and often dominate in the seashore near fluctuating water level. The ability of these lichens to inhabit various environments is associated with their unusually wide range of photobionts. However, this symbiont is not known to most of them. This work investigates the diversity of lichens of the family Verrucariaceae in the littoral zone of the Baltic and the North Sea coasts, the relationships between symbionts and the connection between lichen diversity and the salinity gradient. Using metabarcoding, the diversity of free-living algae in the vicinity of the studied lichens is determined and the symbiotic algae are compared with the photobionts found in the lichens. Mycobionts and photobionts were identified using ITS and 18S rDNA. A total of nine lineages of mycobionts and photobionts were found. The most common lichen turned out to be the species Hydropunctaria maura with its photobiont Pseudendoclonium submarinum. For several...
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Photobiont dynamics of Stereocaulon lichens
Vančurová, Lucie ; Škaloud, Pavel (advisor) ; Bérešová, Anna (referee) ; Dal Grande, Francesco (referee)
7 Abstract Lichens are an iconic example of symbiosis. They are widespread throughout the world. In some ecosystems, lichens are dominant autotrophs, sometimes one of the few living organisms capable of surviving local conditions. They grow on a variety of substrata, including artificial surfaces. Great diversity of their life strategies is related to the diversity of symbiotic partners forming the lichen thalli, which remains largely unresearched. Lichens as sessile organisms often have to face a changing environment or adapt to conditions at new localities where their propagules can spread. We have chosen the widespread genus Stereocaulon as a model system for studying symbiotic relationships in lichens and the connection of this relationships with environmental conditions. The main goals of this thesis were (1) to uncover the diversity of phycobionts (i.e., green algal photobionts) associated with Stereocaulon within the whole genus and particular species-level lineages; (2) to identify environmental factors affecting the distribution of phycobionts and their relationships with mycobionts on a global and local scale; and (3) to inspect the possibility of sharing phycobiont pool with other lichens and soil. For this purpose, we used phylogenetic analyses (ITS rDNA, 18S rDNA, rbcL, and actin type I gene),...
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Stratification risk of disease progression in patients with abnormal cervical cytologic finding by means of molecular genetic analysis of selected biological factors
Gomolčáková, Barbora ; Kašpírková, Jana (advisor) ; Španielová, Hana (referee)
The aim of this thesis was to track the impact of selected herpesviruses, polyomaviruses, Chlamydia trachomatis and methylation of tumor supressor genes at the development and progression of high grade- lesion in HPV - positive patients by means of molecular-genetic techniques. Confirmation of these markers presence in women with severe lesions of cervix would help to raise necessary specificity of molecular genetics HPV testing and recommend it as a primary screening test for cervical carcinoma prevention. HPV testing could thus replace currently prevailing cytology which has relatively low sensitivity and therefore the number of false negative results. The analyzed samples consisted of cytological cervical smears of 51 HPV positive women, with histologically confirmed presence of severe lesions, collected in liquid medium. Samplings from 51 women without infection were used as a control. The possible effect on disease progress was confirmed only in the case of gene promoters' methylation whose presence was detected in up to 26 patients. It is, however, very unlikely that cancer would develop in all these women. This marker could thus help to stratify patients at risk but only to some extent. Although the individual effect of remaining markers has not been established in the carcinogenesis of cervical...
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The efect of environmental variables on diversity of lichen photobionts
Červenková, Tereza ; Škaloud, Pavel (advisor) ; Peksa, Ondřej (referee)
Lichens represent a synergistic combination of at least two organisms, a heterotrophic fungus and a photosynthetic alga or a cyanobacterium. This association has resulted in a symbiotic organism, which is well tolerant to environmental influences. In fact, symbiotic relationship provides mutual benefit for both organisms. It is generally well known that the fungal partners of lichens are far less sensitive to environmental conditions, such as the temperature, altitude, rainfall or the type and composition of the substrate, in comparison to their algal partners. Therefore, lichen forming fungi have much wider ecological valences than the photobionts interacting with them. Indeed, most of the photosyntetic genera and species are adapted only to certain environmental conditions. For this reason, the symbiotic algae and cyanobacteria probably play a major role during the initial lichen formation on the site. This thesis focuses on the adaptability of photoautotrophic symbionts of lichens, coccoid green algae and cyanobacteria, to environmental conditions. Ecological diversification of photobionts has a direct impact on their genetic differentiation and thus to differentiate lichen species themselves. Unfortunately, in many studies the authors mostly dealt with the diversity of macroscopic symbiotic...
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