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Sledování vlivu simulované intenzity deště na zeminu zatíženou splachovými vodami metodou EIS / Monitoring the impact of simulated rainfall on soil with flushing water by EIS methodSlezák, Jakub January 2015 (has links)
The diploma thesis with name “Monitoring the Impact of Simulated Rainfall on Soil with Flushing Water by EIS Method” deals with the problems of soil degradation due to salinization and sodification in consequence of infiltration of flushing waters from roads during winter maintenance. This experiment was realized in laboratories of the Institute of water structures of the Faculty of Civil engineering at Brno University of Technology and researched the influence of simulated rainfall on degraded soil by method of electrical impedance spectrometry (EIS). The thesis follows the solution of projects in international EUREKA program.
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Optimalizace a aplikace spektrofotometrického stanovení jodu v půdách. / Optimalization and application of iodine spectrophotometric determination in soils.HŘIVNÁČ, Jakub January 2012 (has links)
This work deals with the content of iodine in soils, furthermore with obtaining and processing samples from four selected sampling areas, all of which are in the proximity of the Arnoštov settlement in district Prachatice in the foothills of Šumava. The soil samples were obtained from forest, meadow, pasture and fallow soil in 2009 to 2011. The iodine content in the soils was determined by using the spectrophotometric method, which had been optimized for the soil samples. Iodine concentration in lysimeter water was determined by using method inductively coupled plasma - mass spectrometry. The results obtained from each sampling areas were compared with each other and with the results from other areas. Consequently, the iodine concentration results in the soils were compared with the iodine concentration in lysimeter waters. It was found, that the highest iodine content in soils was measured in a sample obtained from Area 1 (meadow), part B in a depth of 16 - 30 cm in June of 2009, namely a content of 8,67 mg of I per kg of dry soil. The lowest content of 1,42 mg of I per kg of soil was found in the area 4 (forest), sample obtained in June of 2010, in the L horizon. By comparing iodine content with iodine concentrations in lysimeter waters, it was concluded that the concentration of iodine in lysimeter waters does not depend on iodine concentrations in soils and that it does not even represent the absolute iodine content in soil, as was determined by comparing the results from Arnoštov with data acquired from Agrovýzkum Rapotín in Jeseníky.
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Proteomické přístupy ke studiu nádorových onemocnění / Proteomic approaches in cancer biologyLorková, Lucie January 2014 (has links)
Proteomics as a modern comprehensive approach to the analysis of proteomes was applied in three projects aimed at diagnosis and therapy of cancer. The aim of the first the project was to find a new diagnostic biomarker for ovarian cancer. Two different comparative proteomic approaches were used for comparative analysis of sera from patients diagnosed with ovarian cancer and from healthy age-matched women. We identified -1-antitrypsin with increased concentration in patien sera, and apolipoprotein A4 and retinol-binding protein 4 (RBP4) with significantly decreased concentration in patients. The significantly decerased concentration of RBP4 in patients is a new observation. We propose that RBP4 is either decreased in ovarian cancer patients as a result of its reduced production by ovary or it may reflect less specific systemic changes, for instance early onset of cancer cachexia. The second project was focused on gaining insight into the molecular mechanism of cytarabine resistance in mantle cell lymphoma (MCL). Proteomic and transcriptomic analyses of cytarabine-resistant cells revealed marked downregulation of deoxycytidine kinase (DCK) - a protein essential to intracellular activation of purine and pyrimidine nucleosides and their analogues including cytarabine. The cytarabine-resistant MCL...
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Proteomická analýza rozpustných i membránových proteinů buněk lymfomu / Proteomic analysis of soluble and transmembrane proteins in human lymphoma cellsVít, Ondřej January 2017 (has links)
In the works presented here, we studied molecular changes associated with drug resistance in human mantle cell lymphoma (MCL) cells using proteomics. Our analyses allowed us to identify causal and/or secondary changes in protein expression associated with the development of resistance to the experimental drug TRAIL and the clinically used antimetabolites cytarabine and fludarabine. Resistance of MCL cells to the recombinant proapoptotic cytokine TRAIL was associated with downregulation of key enzymes of purine metabolism. This pathway potentially represents a molecular "weakness", which could be used as a therapeutic target for selective elimination of such resistant cells. Resistance to the pyrimidine analog drug cytarabine was associated with cross-resistance to other antinucleosides. Proteomic and transcriptomic analyses showed pronounced downregulation of deoxycytidine kinase (dCK), which activates both purine and pyrimidine antinucleosides. This change explains the cross-resistance and is the causal mechanism of resistance to cytarabine. Our observations suggest that MCL patients, who do not respond to cytarabine-based therapy, should be treated with non-nucleoside drugs. MCL cells resistant to purine-derived antinucleoside fludarabine were cross-resistant to all tested antinucleosides and...
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Identification of interacting partners of Discs overgrown in vivo / Identification of interacting partners of Discs overgrown in vivoHOUFKOVÁ, Petra January 2009 (has links)
The mutated forms of the Discs overgrown gene causes overproliferation of imaginal discs of Drosophila melanogaster. Somatic mutations in its human counterpart, casein kinase I epsilon, were strongly associated with human breast cancer. Using the advantage of a high conservancy between fly's dco and human casein kinase I epsilon genes we have chosen D. melanogaster as a model organism to provide a list of probable Dco interaction partners via tandem affinity purification and mass spectrometry analysis. However, these proteins need to be independently verified as true Dco interaction partners.
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Konstrukce a porovnání elektrochemických cel pro stanovení olova technikou generování těkavých sloučenin / Construction and comparison of electrochemical cells for lead determination by volatile compounds generation techniqueHillmich, Ondřej January 2017 (has links)
This diploma thesis is focused on the construction of the electrochemical cells for the lead determination using electrochemical generation of volatile compounds connected with the atomic absorption spectrometry as a detection technique. Three different electrochemical cells were constructed: membrane electrochemical cell (MEC), non-membrane electrochemical cell 1 (BEC1) and non-membrane electrochemical cell 2 (BEC2). Experimental conditions were optimized in continuous flow mode with cells BEC1 and BEC2. The optimization include flow rate of carrier gas, composition and concentration of the electrolytic solution, atomization temperature, generation current and voltage applied to the electrode material. A 1.0 mm diameter cadmium wire was used as cathode material and the anode material was composed of platinum wire of 0.5 mm in diameter. Under the optimal experimental conditions, the calibration was constructed and basic characteristics of proposed method were determined for the BEC1 and BEC2 cells: limit of detection, limit of quantification, repeatability, sensitivity, linear dynamic range and correlation factor of linear dynamic range. The cell MEC was found to be unsuitable for the lead determination by the electrochemical generation of volatile compounds. Using the BEC1 cell, the experimental...
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Tenzidy v povrchových a odpadních vodách / Surfactants in Surface and Waste WaterŠtefka, Michal January 2017 (has links)
This work is focused on the occurrence of surface-active substances in the environment. It deals with the development and optimization of methods for the determination of selected surfactants in samples from rivers and from influent and effluent of wastewater treatment plants. Representatives of anionic, nonionic and zwitterionic surfactants were selected as target compounds. Based on optimization of analytical methods and their pilot testing abroad on samples of surface water, the selection of analytes for the conditions in the Czech Republic were corrected and operatively expanded. For the final analysis liquid chromatography with mass spectrometry was used. Analysis of cationic surfactants was realized using liquid chromatograph with UV-VIS detector. This optimized method for analysis of anionic surfactants was applied to real samples. Samples of surface running water were from the River Thurso in Scotland and then from watercourses in the catchment area of Moravia river were collected. In addition to the grab sampling also continuous weekly sampling of water from Tvaroženský potok and Litava was realized. Waste water was collected at inflow and outflow of three wastewater treatment plants (WWTP) in South Moravia (Brno – Modřice, Břeclav and Hodonín).
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Gravitational Waves Spectrometry in Space with a Hong-Ou-Mandel InterferometerJacinto de Matos, Clovis 13 October 2021 (has links)
In der vorliegenden Dissertation wird ein neues experimentelles Konzept zur Durchführung von Gravitationswellendetektion und Spektrometrie mit einem Hong-Ou-Mandel (HOM) Interferometer im Weltraum untersucht. Dabei wird das Rauschbudget des Instruments bewertet. Die grundlegenden experimentellen Anforderungen werden berechnet. Es wird gezeigt, dass die Leistung und Wellenlänge der verschränkten Photonenquelle, zusammen mit der Winkelgenauigkeit der Messung der Photonenpolarisationsdrehung, die Haupteinschränkungen bilden, um die Art der Gravitationswellenquellen zu bestimmen, die das Ziel von HOM - Gravitationswellenspektrometern sein würden. Die derzeit verfügbaren pW-Leistungen mit typischen Photonenfrequenzen in der Größenordnung von 1014 Hz (sichtbarer - UV-Anteil des optischen Spektrums) sind völlig ungeeignet, was die erforderliche Detektionszeit für eine der Gravitationswellenquellen betrifft, die derzeit von bodenund raumgestützten Gravitationswellendetektoren anvisiert werden. Der Betrieb des HOM-Interferometers als GW-Spektrometer wird mit einem numerischen Modell veranschaulicht, das die von LIGO am 14 September 2015 (GW150914-Ereignis) aufgezeichneten Gravitationswellendehnungsdaten verwendet. Unter der Annahme einer Winkelgenauigkeit von μrad für die Messung der Polarisationsdrehung von Photonen könnten diese Messungen nur mit Armlängen des HOM-Interferometers in der Größenordnung von 10.000 km (nur im Weltraum erreichbar, wenn wir keine optischen Kavitäten verwenden) und unter Verwendung von verschwänkten Photonenquellen von etwa 1 W Leistung durchgeführt werden, die verschränkte Photonen mit Wellenlängen im Radiowellenbereich des elektromagnetischen Spektrumserzeugen, (10 MHz), und unter Verwendung von Photodetektoren mit minimaler Detektionszeit für einzelne Photonen und minimaler detektierbarer Leistung, die weit von den Möglichkeiten der gegenwärtigen Photodetektortechnologie entfernt sind. Auch die erforderliche Präzision der Uhrensynchronisation, um die Koinzidenz- Zählgeschichte zu erfassen, ist noch ange nicht erreicht. Obwohl die Technologie zur Herstellung der erforderlichen verschränkten Photonenquellen, Photodetektoren und Uhrensynchronisationsgenauigkeit derzeit nicht verfügbar sind, diskutieren wir verschiedene Missionsszenarien zur Implementierung eines großarmigen HOMInterferometers.:Contents
1 Introduction 1
2 Gravitational waves and their measurement 7
2.1 Theory of general relativity in a nutshell . . . . . . . . . . . . . . . . 8
2.2 On the physical nature of gravitational waves . . . . . . . . . . . . . 13
2.2.1 Effect of gravitational waves on the test masses of a detector . 15
2.2.2 Estimation of gravitational wave’s amplitude . . . . . . . . . . 18
2.2.3 Gravitational radiation luminosity and cross section of the
Hydrogen atom to GWs . . . . . . . . . . . . . . . . . . . . . 21
2.3 Measuring cosmic distances with GW astronomy . . . . . . . . . . . . 25
2.4 Influence of gravitational waves on photon’s polarization . . . . . . . 28
2.4.1 Effect of gravitational waves on the parallel transport of photon’s
polarization four-vector - revisited . . . . . . . . . . . . 29
2.4.2 Effect of primordial gravitational waves on the polarization of
the cosmic microwave background . . . . . . . . . . . . . . . 36
2.4.3 Gravitomagnetic Faraday effect . . . . . . . . . . . . . . . . . 40
2.5 Michelson type gravitational wave antennas . . . . . . . . . . . . . . 41
2.6 Rough estimation of the sensitivity and cross section of Michelson
type detectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
3 Interaction of gravitational waves with Hong-Ou-Mandel interferometers 47
3.1 Fundamental nature of quantum entanglement in brief . . . . . . . . 47
3.2 Why a HOM interferometer to detect GWs? . . . . . . . . . . . . . . 50
3.3 Quantum mechanics of Hong-Ou-Mandel interferometers . . . . . . . 54
3.4 Principle of gravitational waves detection with a Hong-Ou-Mandel
interferometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
3.5 Instrument noise budget . . . . . . . . . . . . . . . . . . . . . . . . . 68
3.6 Basic experimental requirements for HOM based gravitational waves
detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
4 Gravitational waves spectrometry with a Hong Ou Mandel interferometer
in space 77
4.1 Principles of gravitational waves spectrometry with a Hong-Ou-Mandel
interferometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
4.2 Hong-Ou-Mandel spectrometer in geostationary orbit . . . . . . . . . 93
4.3 Hong-Ou-Mandel spectrometer scanner in space . . . . . . . . . . . . 95
5 HOMER mission scenarios for gravitational waves spectrometry - basic
design requirements 97
5.1 HOMER mission design analysis . . . . . . . . . . . . . . . . . . . . . 98
5.1.1 HOMER GEO mission . . . . . . . . . . . . . . . . . . . . . . 99
5.1.2 HOMER ground-GEO mission . . . . . . . . . . . . . . . . . . 105
5.1.3 HOMER scanner mission . . . . . . . . . . . . . . . . . . . . . 106
5.2 Influence of earth gravitomagnetism on photon polarization . . . . . 106
5.3 Payload design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
5.4 Spacecraft design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
5.5 Summary of HOMER mission requirements . . . . . . . . . . . . . . 120
6 Outlook and conclusions 129
6.1 Outlook . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
6.1.1 HOM gravitational wave detector with optical cavities . . . . 129
6.1.2 Bright entangled heralded photon sources . . . . . . . . . . . 130
6.2 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
7 ANNEX: Detailed derivation of gravitational waves and gravitoelectric
and gravitomagnetic fields 137
7.1 Weak gravitational fields . . . . . . . . . . . . . . . . . . . . . . . . . 137
7.2 General relativity for the practical physicist . . . . . . . . . . . . . . 138
7.3 Gravitational wave equation . . . . . . . . . . . . . . . . . . . . . . . 144
7.4 Gravitoelectromagnetic split of spacetime . . . . . . . . . . . . . . . 145
7.4.1 Gravitational scalar potential . . . . . . . . . . . . . . . . . . 147
7.4.2 Gravitomagnetic vector potential . . . . . . . . . . . . . . . . 147
7.4.3 Space curvature . . . . . . . . . . . . . . . . . . . . . . . . . . 149
7.5 Maxwell-type gravitational equations . . . . . . . . . . . . . . . . . . 151
7.6 Gravitomagnetic waves . . . . . . . . . . . . . . . . . . . . . . . . . . 155
7.7 The equations of motion in the weak field approximation . . . . . . . 156
7.8 Production of gravitational radiation . . . . . . . . . . . . . . . . . . 160
Bibliography 163
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HG-AAS s atomizací v plazmovém výboji s dielektrickou bariérou: optimalizace metody a analytické aplikace / HG-AAS with atomization in a dielectric barrier plasma discharge: method optimization and analytical applicationsZurynková, Pavla January 2016 (has links)
The aim of this diploma thesis was to optimize in detail atomization conditions for antimony hydride in a novel plasma atomizer based on a dielectric barrier discharge (DBD) with atomic absorption spetrometric detection. Argon was found as the best DBD discharge gas employing a flow rate of 50 ml min-1 Ar while the DBD power was optimized at 30 W. Analytical figures of merit including interference study of As, Se and Bi have been subsequently investigated and the results compared to those found in an externally heated quartz tube atomizer (QTA). The limit of detection reached in DBD (0.15 ng ml-1 Sb) is comparable to that observed in QTA (0.14 ng ml-1 Sb). Finally, possibility of stibane preconcentration in a DBD atomizer was studied. Preconcentration efficiency of 102 ± 6 % was found under optimized conditions.
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Hormony v čistírenských kalech / Hormones in sewage sludgeJagošová, Klára January 2018 (has links)
Currently there is a spate of interest in the presence of pharmacologically active substances in the environment. These substances are excreted in active or metabolized form and with wastewater pass the wastewater treatment plant. Current treatment technologies do not always eliminate all pharmaceuticals effectively and therefore they enter the environment. One of these active groups is the group of steroid hormones. Steroid hormones belong to the group of endocrine disruptors and they are considered to be dangerous for the ecosystems. Due to the hydrophobic character of steroid hormones they undergo partial or total sorption from wastewater to sludge. Sewage sludge is the by product of wastewater treatment and contains heavy metals, organic contaminants and pathogenic bacteria. A part of produced sewage sludge is used as a fertilizer in the Czech Republic. This issue follows the regulation 347/2016 – conditions of agricultural use of sewage sludge. Waste policy of EU will alter the conditions of sludge disposal, so it is necessary to obtain data about the concentration levels, fate and behaviour of those pollutants. This thesis was focused on five natural female hormones and four synthetic, which are used as a part of contraceptive pills and substitutional hormonal therapy. Determination of hormones was performed in four steps including ultrasonic assisted extraction, clean up by solid phase extraction, derivatization and final analysis by gas chromatography with mass spectrometry on triple quadrupole in MS/MS mode.
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