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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.
51

Výrobník ledu s přímým odparem / Ice maker with direct evaporation

Loibl, Jan January 2015 (has links)
The theoretical part of the diploma thesis deals with introduction to the issue of refrigeration systems with thermal energy storage. Possibilities of thermal energy storage with phase change are introduced. The thermodynamic principle of functioning of the particular refrigeration system type is explained here as well as its coefficient of performance and fundamental components. In addition, several examples of ice-making systems are discussed. In the practical part the design of a particular refrigeration system is calculated. The main part of the design is the cold evaporator with direct evaporation and the possibility of ice production and its usage for thermal energy storage. The calculation of the overall two-phase heat transfer is carried out.
52

Vliv tepelné vodivosti na efektivitu akumulace tepla / The effect of thermal conductivity on the heat storage efficiency

Steidl, Martin January 2016 (has links)
The diploma thesis is focused on the dependence of heat storage on thermal conductivity, which is characterized by the thermal conductivity coefficient. Two basic materials were chosen for the measurements – universal plaster mixture and gypsum plaster. The thermal conductivity of the materials was increased by adding milled graphite powder, which conducts the heat very well. The taken samples were then examined for differences in the behaviour in the non-stationary thermal field and thermal-technical parameters – the specific heat capacity and the thermal conductivity coefficient – were determined.
53

Vliv akumulace na provoz distribuční sítě / The Effect of Accumulation on Distribution Grid Operation

Jestřáb, Tomáš January 2017 (has links)
This diploma thesis introduces the reader to the possible types of electric energy storage technologies, their comparisons and utilization. After its introduction, it follows the description of individual technologies and principles that are currently meaningful and useful in practice. The thesis continues with the part characterizing the ways of using the accumulation in the grid. However, the main points of this thesis include the analysis of the influence of the photovoltaic installation on the specified distribution grid operation at the low voltage level and the analysis of the influence on the grid with connected accumulation. Another important objective was the model for the calculation of steady-state, which was programmed on the basis of the theory supported by the principles of production from intermittent sources and the principle of accumulation function. The outputs of the model in the form of the calculated voltage ratios at the individual supply points and current flows at the distribution transformer point were used to evaluate the analyzes mentioned above. The courses of the calculated parameters are broken down by different scenarios (according to the period, the degree of integration of production and the accumulation or the power output of the production), graphically processed and compared from the point of view of voltage fluctuations and changes in the power (or current) balance of the supply transformer.
54

Mutační a substituční tempo u sexuálních a klonáních forem: možný klíč k vysvětlení persistence sexu u modelové skupiny sekavců? / Mutation and substitution rates in sexual and asexual forms: a clue to the persistence of sex in a model group of Cobitis?

Röslein, Jan January 2016 (has links)
TITLE: Mutation and substitution rates in sexual and asexual forms: a clue to the persistence of sex in a model group of Cobitis? AUTOR: Jan Röslein DEPARTMENT: Ústav živočišné fyziologie a genetiky AVČR, v.v.i. SUPERVISOR: Mgr. Karel Janko, Ph.D. ABSTRACT: Subject of this thesis is to test several hypotheses about the evolution of asexual reproduction in model group of fish family Cobitis and its mutual competition among sexual and asexual forms, which touches one of the oldest unresolved issues of biology. Specifically, the work deals with the accumulation of non-synonymous mutations, which accelerated accumulation in the genome of clonal lineages theoretically leads to increased extinction compared with sexually reproducing populations (so-called. The theory of Muller's ratchet and Kondrashov's hatchet). This thesis is based on a normalized cDNA sequencing data from oocytes and liver tissue, which has served as a base matrix (generated based on non-normalized cDNA data) for transcriptome sequencing (RNAseq). Consequently, the RNAseq data have served as validation for acquired polymorphisms, detection of differential expression of allele- specific expression (ASE) hybrid biotypes. This diploma thesis balances among the edges of vast spectrum of hypotheses regarding the evolution of the genus hybrid...
55

Role akumulace železa a dalších kovů v patofyziologii neurodegenerativních onemocnění / The role of accumulation of iron and other metals in the pathophysiology of neurodegenerative diseases

Mašková, Jana January 2020 (has links)
The role of metal accumulation in the pathophysiology of neurodegenerative diseases has been a hot topic in recent years due to the possibility of its treatment by chelating agents. Although the mechanisms of neurodegeneration are well known, the role of metal accumulation is still unclear. The main limitation are unsatisfactory methods for in vivo metal imaging; the most widely used technique is magnetic resonance imaging (MRI). Our aim was to assess the possibility of using transcranial sonography (TCS) in differential diagnosis of neurodegenerative diseases and to further explore the underlying factors of echogenicity. In the first study, using TCS fusion with MRI, we focused on location verification of the commonly assessed structures (substantia nigra and nucleus lentiformis) and exclusion of possible focal structural changes affecting the echogenicity in WD and PD patients. Moreover, obtained MRI were used for semi-quantitative comparison with TCS images. Although TCS has been confirmed to be highly beneficial in differential diagnosis of Wilson's disease and it should be recommended as a screening method for extrapyramidal patients with atypical course of the disease, the direct relationship between TCS and metal deposits could not be proven. The obtained results from the ultrasound fusion...
56

"Domácí elektrárny - dostupnost a ekonomická opodstatněnost technologií pro domácí výrobu elektrické energie pro rodinné domy v ČR / Household power stations - accessibility and economic viability of technologies for household electricity generation in family houses in CR

Zlonický, Jan January 2017 (has links)
This thesis focuses on the question whether it is economically viable to operate a system for household electricity production and if so, what are the necessary conditions to do so. In the text of this thesis a brief summary of environmental protection and sustainable development is presented, followed by the description and current state of technologies needed to construct systems for electricity production in the scale of family houses with focus on photovoltaic systems, and a description of the current legislation and administrative barriers related to this subject. Economic view (costs and return of investment) is examined in relation to multiple conditions, focus of this examination being on the geographical conditions, legislation and administrative conditions, state subsidies, electricity production and consumption profiles in the household and electricity price development scenarios. Technologies for household electricity production are therefore put into the context relevant to the citizens of the Czech Republic. The results of this work show, that the systems for photovoltaic electricity production in family houses in the conditions of the Czech Republic are economically viable with the premise that the surpluses of electricity produced are effectively consumed, for example for water...
57

Integrace materiálů s fázovou změnou ve stavebních konstrukcích / Integration of phase change materials in building structures

Klubal, Tomáš January 2017 (has links)
The thesis deals with the integration of phase change materials (PCMs) into building structures. The basic requirement is improved thermal stability during the summer season without using an air conditioner. This can be achieved by increasing the thermal storage capacity of the building structures. If the thermal capacity cannot be increased on the level of weight, phase change materials can be used. These materials are capable of storing latent heat and thus increasing the thermal storage capacity of the building. In the thesis the phase change materials were investigated in a thermal incubator by thermal analysis and, above all, in full-scale experiments using comparative measurements. The comparative measurements were carried out in two attic rooms at the Faculty of Civil Engineering, Brno University of Technology, where in one was used as a reference and the other for the experiment. Manufactured heat storage panels were installed in the experimental room. These panels are composed of a base plate; the capillary tubes placed on it are coated with modified plaster. The gypsum plaster is modified with micro-capsules paraffin for improving the thermal storage capacity. This system is connected to a thermal air-water pump, by which the storage panels can be additionally cooled or heated. In the experimental measurements, different operating modes were investigated and their effect on the indoor environment was evaluated. Thermal storage in PCMs dampens the temperature amplitude in the building during the summer season and, at the same time, allows the stored heat to be discharged during the night. Moreover, the time interval of withdrawing electric energy from the supply mains is much shorter than in the case of air conditioning. A conventional air conditioner must operate simultaneously with the thermal load, i.e. at the time of peak consumption of electric energy. Thanks to the set regimes, the installed system is capable of responding to external thermal condit
58

Role lékových transportérů v placentárním přestupu entekaviru / Role of drug transporters in placental transfer of entecavir

Křečková, Veronika January 2019 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Veronika Křečková Supervisor: PharmDr. Lukáš Červený, Ph.D. Title of diploma thesis: Role of drug transporters in placental transfer of entecavir Entecavir (ETV), an analogue of guanosine, is a highly efficient anti-hepatitis B antiviral drug. It is the first-line therapy for both adults and children. Its use in pregnancy is limited due to a number of factors, including lack of data on placental pharmacokinetics. The placental transition of drugs is frequently controlled by drug transporters. ATP-binding (ABC) transporters, P-glycoprotein (P-gp), breast cancer resistance protein (BCRP) or multidrug resistance-associated protein 2 (MRP2) localized in the apical membrane of syncytiotrophoblast and pumping their substrates in the feto-maternal direction belong to most significant determinants of placental pharmacokinetics. Moreover placental transport of nucleoside-derived drugs can be affected by the activity of nucleoside transporters (NTs); equilibrative nucleoside transporters (ENTs) mediate facilitated diffussion, while the concentrative nucleoside transporters (CNTs) control active influx of their substrates. The aim of the diploma thesis was to describe the role of P-gp, BCRP, MRP2 and NTs (ENTs and...
59

Studium interakcí antiretroviálního léčiva tenofoviru a jeho proléčiva tenofoviru disoproxil fumarátu s placentárními nukleosidovými transportéry / Study of interactions of antiviral drug tenofovir and its prodrug tenofovir disoproxil fumarate with placental nucleoside transporters

Lalinská, Anežka January 2018 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Anežka Lalinská Supervisor: PharmDr. Lukáš Červený, Ph.D. Title of diploma thesis: Study of interactions of antiretroviral drug tenofovir and its prodrug tenofovir disoproxil fumarate with placental nucleoside transporters Tenofovir (TFV) in the form of ester prodrug tenofovir disoproxil fumarate (TDF) is an essential part of combination antiretroviral therapy. It is often used in the prevention of perinatal HIV transmission. However, precise mechanism(s) involved in transfer of TFV/TDF from mother to fetus are not described in detail. Since these drugs are nucleoside analogues, there is a possibility that the mechanisms of their transplacental passage might include nucleoside transporters (NTs), either equilibrative or concentrative (ENTs/CNTs). The aim of the diploma thesis was to investigate the role of placental NTs in membrane transfer of TFV and TDF. To address this issue, we performed in vitro accumulation in the BeWo cell line derived from placental choriocarcinoma. By evaluating experiments, we found out that both TFV and TDF might not be substrates of NTs, thus the role of these transporters in TFV/TDF placental pharmacokinetics was not confirmed. Therefore, the drug-drug interactions on NTs...
60

Studium interakcí antivirálních látek s intestinálními lékovými efluxními ABC transportéry / Study of interactions of antiviral drugs with intestinal drug efflux ABC transporters

Huličiak, Martin January 2018 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Martin Huličiak Supervisor: PharmDr. Lukáš Červený, Ph.D Title of diploma thesis: Study of interactions of antiviral drugs with intestinal drug efflux ABC transporters P-gp, MRP2 and BCRP are efflux transporters, members of the family of ATP binding cassette (ABC) transporters. These transporters are located on the apical membrane of the intestinal epithelium, where they may limit absorption of orally administered drugs. Study of drug interactions with/on intestinal efflux transporters is necessary to provide safe and effective treatment. The Caco-2 cell line is FDA recommended in vitro model of intestinal barrier and it is used for bidirectional testing of substrates and inhibitors of ABC transporters in preclinical research. However, this methodology has several shortcomings, so the need of introduction of new experimental models is increasing and the ex vivo method based on human or rat intestine is a promising option. Precision-cut intestinal slices (PCIS) represent a mini-model of the organ and contain all types of cells of the tissue. We used both in vitro model using Caco-2 cell monolayers for drug transport study and in our lab established ex vivo method of PCIS for accumulation study...

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