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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Vazbení / Feedback

Koniar, Martin January 2019 (has links)
My diploma work is an installation, made from multiple instances of a device iniciating string resonance via electromagnetic field. These devices along with strings are placed on the wall in geometrical shape. Installation creates loop on multiple levels. Except the fact that installation have a circular shape, position of each string starts at the end of another string. Second, more inconspicious loops takes place in the electromagnetic device resonating the strings, that do that with feedback loop. Strings consist every step of chromatic scale, that repeats itself, just an octave higher. Amplification of the final sound of strings is done purely acoustically, with help of the wall on wich the piece is installed. This piece is in its nature concerned with spirituality in music, not necessarily in sense of evoking a spiritual experience, but rather demonstrating metaphors and parallels, that exists between physical aspects of tonal music and different religious ideas. The symmetrical shape of installation refer to religious and occult visuality, built f.e. in cabal on Fibonacci numbers, that is present not only in nature ( for example, the veins of the leaves grow by these numbers), but also in tonal music system (ancient philosophers were working with this concept, see Plato's Music of the Spheres). Strings in this piece produce drone sound, that is naturally evoking spirituality (most visible in buddhist monk meditation). This sound in the piece demonstrates immutability and constancy, the fact that all the chromatic tones are playing demonstrates wholeness (this fact may produce interesting resonances emerging between chromatic steps), so to speak, the unchangeable laws of physics, or to put it in religious lingo, the god law. The symbol of loop also refers to religion, like the eternal return of the same, the periodicity of history. Strings can be viewed as astrophysical symbol. Everything stated is nothing but my recourse, that should not ultimately determine the perception of the piece by viewer. The goal of the work is to offer experience without need to be put into context
32

Komplexní předoperační zobrazování nádorů mozku / Complex Preoperative Brain Tumor Imaging

Tupý, Radek January 2018 (has links)
Title Complex preoperative brain tumor imaging Abstract The differentiation of glioblastoma, metastases and brain lymphoma using modern diagnostic imaging methods has a major impact on the strategy of further diagnostic examinations and treatment. In a group of 67 patients with glioblastoma and 31 with cerebral metastasis, the ability to differentiate them according to the evaluation of perfusion parameters changes in peritumoral white matter by T1 dynamic post-contrast magnetic resonance imaging was verified, with the positive predictive value in glioblastoma detection up to 91%. In a group of 36 brain lymphoma patients the importance of imaging submodalities and contribution of a complex magnetic resonance imaging protocol to detect lymphoma up to 80% were evaluated. Key words brain, glioblastoma, lymphoma, magnetic resonance imaging, neoplasm metastasis
33

Radiofrekvenční metoda detekce výbušnin a drog - NQR / RF detection method of explosives and drugs - NQR

Motyčka, Lukáš January 2013 (has links)
The thesis deals with RF spectroscopic methods, which are applicable for the detection of hazardous substances such as explosives or drugs. Particular attention is focused on promising method of nuclear quadrupole resonance. Abroad this method has recently been applied in the detection of energetic materials in hazardous locations. The cornerstone of the nuclear quadrupole resonance is to evaluate the interaction between electromagnetic radiation, in the range of medium to very short waves, and the researched substance. Observed parameter are the resonant frequencies of the substance. Spectral analysis of signal is used for their evaluation. Resonant frequencies are always typical for the crystalline structure, therefore every explosive or drug is clearly identifiable by this method.
34

Diagnostický algoritmus karcinomu prostaty / Prostate Cancer Diagnostic Algorithm

Sedláčková, Hana January 2021 (has links)
Prostate cancer diagnostic algorithm Aim: The aim of the study is to implement the latest scientific knowledge in the diagnosis of prostate cancer (PC). We focused on tumor markers, imaging methods, prostate biopsy methodology and we created a diagnostic algorithm based on a review of current literature in combination with our own experience. Material and methods: The algorithm is divided into several branches, which have been individually subjected to clinical studies. Due to the low sensitivity and specificity of PSA, prostate health index (PHI) was added to the first line of patient stratification. 787 patients were primarily examined and these subsequently underwent radical prostatectomy. PHI levels were compared with definitive staging and grading. Cut-off values for PC detection and high-risk stratification, including locally advanced PC were determined. Next, 320 patients underwent prostate biopsy followed by radical prostatectomy. The cohort was further divided into two subgroups, patients with GS = 6 and patients with GS > 6. The ability of PHI to distinguish between insignificant and significant prostate cancer was evaluated. In a multicentric study with 395 patients, PHI with additional markers (tPSA, PSAD) and multiparametric magnetic resonance imaging of prostate (mpMRI) was assessed....
35

Analýza genů indukovaných abiotickým stresem u řepky / Analysis of abiotic stress induced genes in rape

HOŠTIČKOVÁ, Irena January 2019 (has links)
Breeding for abiotic stress tolerance is one of main topics in plant breeding. Oilseed rape breeding programs were for a long time focused on morphological and physiological parameters. In this thesis few experiments focused on identification of genes involved in abiotic stress reaction were performed using RT-qPCR (quantitative reverse transcription PCR). Simultaneously SPR (surface plasmon resonance) method were used as modern optical method facilitating very low native protein concentration even in presence of other substances. This method facilitates quantification of concrete proteins by binding them to specific antigen and in oilseed rape research it was not used by now. ERD10 protein was identified by SPR as protein involved in cold stress reaction (or acclimation). The results show ERD10 accumulation in standard conditions affects dynamics of its accumulation change during cold stress. In case we are searching for genotypes great in acclimation ability even during short and warm autumn SPR method should be suitable method for fast, easy and relatively cheap screening of large number of genotypes in breeding collections. Also genes LTI78, RCI2A, NRP1 and two genes for hypothetical proteins were analysed. Their relative expression during cold stress was markedly increased too. Very little is known about these genes and proteins nowadays therefor it will be interesting topic of our oncoming experiment. Relative expression of genes picked according to MALDI-TOF/TOF analysis results was also tested in microspore embryo regenerants stressed by simulated drought. Genes for lactoylglutathione lyase I, phospholipase D 1 and peroxiredoxin antioxidase were tested. In tolerant cultivar was markedly decreased gene expression of peroxiredoxin antioxidase in standard conditions and early stress. These gene will be subject for next research as potential marker for more tolerant genotypes selection.
36

Chirurgické možnosti léčby degenerativního onemocnění thorakolumbální páteře: Význam morfologických a klinických klasifikací stenózy bederní páteře v předoperační rozvaze / The Surgical Treatment Options in Thoracolumbar Spine Degeneration: The Importance of Morphological and Clinical Classifications in Preoperative Decision Making

Bludovský, David January 2019 (has links)
The surgical treatment options in thoracolumbar spine degeneration: The importance of morphological and clinical classifications in preoperative decision making David Bludovský Abstract: Objective: The aim of our study was to investigate the relations between subjective difficulties, clinical findings and the MR imaging in patients who have been operated for symptomatic lumbar spinal stenosis (LSS), and the possibility of using these relations for surgical treatment decision. Methods: Patients operated for lumbar spinal stenosis in 2009-2010 were included in the study. Subjective difficulties were assessed using the Oswestry Disability Index (ODI), the clinical symptoms with the modified Neurological Impairment Score for Lumbar Spinal Stenosis (mNIS-LSS). We measured the spine canal area, dural sac area, and nerve root sedimentation classification on MR. By correlation analysis at significance level p <0.05, we tested the relations between these categories. 61 patients with a median age of 67 were included. Overall, we evaluated 162 spinal segments. Results: Median of ODI values were 48. Correlation coefficients for ODI, mNIS-LSS and graphical findings were less than 0.5. Correlation coefficients greater than 0.5 were between all the MR measurement methods. Conclusions: In the group of patients indicated...
37

Teoretický popis kolektivních excitací jader / Theoretical description of nuclear collective excitations

Repko, Anton January 2016 (has links)
Density functional theory is a preferred microscopic method for calculation of nuclear properties over the whole nuclear chart. Besides ground-state properties, which are calculated by Hartree-Fock theory, nuclear excitations can be described by means of Random Phase Approximation (RPA). The main objective of the present work is to give the RPA formalism for spherically symmetric nuclei, using the techniques of angular-momentum coupling. Various auxiliary topics, such as Hartree-Fock theory, Coulomb integral, center-of-mass corrections and pairing, are treated as well. RPA method is derived also for axially deformed nuclei. The derived formulae are then implemented in the computer code and utilized for calculation of some physical results. After thorough investigation of the precision aspects of the calculation, the following topics are treated as examples: toroidal nature of the low-energy (pygmy) part of the E1 resonance, giant resonances of various multipolarities in deformed nucleus 154Sm, and magnetic dipole (M1) transitions in deformed 50Cr. Powered by TCPDF (www.tcpdf.org)
38

Kontrastní látky pro heteronukleární MRI / Contrast agents for hereronuclear MRI

Koucký, Filip January 2018 (has links)
In this thesis the pH dependency of the coordination modes of lanthanide complexes with macrocyclic ligands based on 1,4,7,10-tetraazacyclododecane skeleton was studied. The cyclen-based ligand structures in this work contained three acetate and one aminoethyl group with a N-alkyl-N-methylphosphonate substituent, DO3AN(R)P, where R is an alkyle substituent on the nitrogen atom of the pendant arm (R = methyl, benzyl). Lanthanide complexes of a previously studied prototype ligand DO3ANP with secondary amino group (R = H) have shown interesting properties in the field of 31 P NMR imaging because of their various coordination properties, which allow in situ pH measurement. These complexes can also be used for monitoring the kinetics of the chemical exchange of the amino group proton in 1 H NMR imaging using the chemical exchange saturation transfer (CEST NMR). In this thesis, two new derivatives DO3ANMeP and DO3ANBnP were prepared in order to better understand the coordination modes changes in this ligand series. Also, their coordination behaviour with selected lanthanide ions was studied (Eu3+ , Gd3+ , Dy3+ , Yb3+ ). Based on a series of NMR and luminescence measurements, it was found out, that in acidic conditions the complexes containing DO3ANP motif bind a water molecule in their coordination...
39

Využití magnetické rezonance srdce pro posouzení patofyziologie dilatační kardiomyopatie. / Use of cardiovascular magnetic resonance for evaluation of pathophysiollogy in dilated cardiomyopathy.

Šramko, Marek January 2015 (has links)
Dilated cardiomyopathy (DCM) is the second leading cause of heart failure. The pathophysiology in DCM is still poorly understood, partly because of currently limited research tools. We investigated whether cardiovascular magnetic resonance (CMR), using novel imaging techniques, could be used for in vivo assessment of some key pathophysiological mechanisms related to DCM. In addition, we evaluated whether the pathological findings on CMR would predict clinically relevant functional and morphological improvement of the left ventricular (LV) function - the LV reverse remodeling (LVRR). CMR together with endomyocardial biopsy, echocardiography, cardiopulmonary exercise testing and a thorough assessment of cardiac biomarkers was performed in 44 patients with new-onset DCM (<6 months of duration). The imaging was repeated after 12 months of clinical follow-up. Endomyocardial biopsy revealed myocardial inflammation in 34 % of the patients. LVRR at 12 months occurred in 45 % of the patients. Presence of late gadolinium enhancement (LGE) in the left ventricle was a sensitive but unspecific sign of myocardial inflammation because it was also a feature of hemodynamic stress related to the heart failure. The baseline extent of LGE was an independent predictor of future LVRR and also a predictor of adverse clinical...
40

Použití magnetické rezonance spektroskopie při studiu glukózového metabolismu / The use of magnetic resonance spectroscopy for studying glucose metabolism

Kratochvílová, Simona January 2018 (has links)
Magnetic resonance spectroscopy (MRS) is a noninvasive technique that enables to follow metabolic processes in selected tissues in vivo. Recently the attention has been focused on metabolic mapping in target organs of insulin action to describe the pathophysiology of insulin resistance. The aim of our study was to present the practical application of ³¹P (phosphorus) MRS and ¹H (proton) MRS in metabolic studies of skeletal muscle in insulin resistant subjects and in subjects with impaired fasting glucose. The third study was aimed to evaluate the brain metabolism with ¹H MRS in healthy controls and subjects with type 1 diabetes during hyperinsulinemia. ¹H and ³¹P MRS were performed using a MR Scanner Siemens Vision operating at 1,5 Tesla. To assess the parameters of glucose metabolism and insulin action oral glucose tolerance test and hyperinsulinemic euglycemic clamp were performed. The study 1 was aimed to evaluate the skeletal muscle (m. soleus) energetic metabolism in the offspring of hypertensive parents (OH) with a higher level of insulin resistance. The concentrations of selected high energy phosphates (phosphocreatine, inorganic phosphate, adenosintriphosphate, phosphomonoesters, phosphodiesters) were evaluated with ³¹P MRS. Their amount in OH was comparable to healthy controls. However we...

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