National Repository of Grey Literature 1,288 records found  1 - 10nextend  jump to record: Search took 0.09 seconds. 

Negative effect of addictive substances on human organism
SKOVAJSA, Radko
In my thesis I have focused on assesment of particular cathegories of drugs and mainly their negative harmful influence on human organism. I have suggested the system of subdivision of those causing drug addiction. I have used specialized literature; books and magazines.

Study of combined climatic influences and hydrophobization effects on sandstone pinnacles from the Santa Barbara church in Kutná Hora
Drdácký, Miloš ; Lesák, Jaroslav ; Slížková, Zuzana ; Pospíšil, Stanislav ; Delpech, P.
The report summarizes results of the first part experiments in the Jules Verne climatic wind tunnel CSTB in Nantes. It presents diagrams of temperature and moisture changes measured on both the exterior surface and inside historic sandstone pinnacles from the church of Santa Barbara in Kutná Hora at different combinations of climatic loads with changing temperature, rain and wind velocity characteristics. Thermography has been applied for surface temperature measurements. During the tests the hydrophobization effect was studied, too.

Drugs and activities that could cause danger to life, health or damage to property
HANDSCHUHOVÁ, Silvie
The objective of this thesis is to summarize the effects of drugs, especially of the cannabinoids and amphetamine type stimulants, and to analyse which of these substances leads to high-risk activities, that could endanger life, health or result in damage to property. One of these activities, an important one, is driving under the influence of drugs. Driving itself is a complex demand, involving perception, decision making, psychomotor skills, knowledge, as well as attitudes and personality characteristics. Substance use and abuse has an impact on the functioning of the brain and mental processes and therefore on the performance of the driving task. Driving under the influence of drugs is a high risk activity which endangers not only the driver but also their surroundings. In the last few years, the Czech Republic registered a rapid increase in the number of impaired drivers, namely at police check points and in car accidents. The young drivers are mostly under influence of marijuana, respectively tetrahydrocannabinol (THC). Its negative effect on driving results from impaired co-ordination, slowed complex reaction time and in space and time distortion. The second group of drugs which can impair drivers is amphetamine type stimulants. Amphetamines are frequently sought by truck drivers, especially long-haul drivers, in Western Europe for its stimulative effects. In the Czech Republic the methamphetamine, Pervitin, is much more common. Intoxication is characterized by increased wakefulness, increased physical activity, increased respiration, rapid heart rate and an irregular heartbeat. The risk factors for driving are a lack of concentration and an overestimation of one{\crq}s own capabilities. After the acute phase of intoxication subsides, fatigue or states of narcolepsy may occur. Another amphetamine-based drug is methylenedioxymethamphetamine, MDMA or Ecstasy. This synthetic substance, chemically related to mescaline, is dangerous due to its ability to regulate body temperature. On rare but unpredictable occasions, this can lead to sharp hyperthermia, resulting in liver, kidney and cardiovascular system failure, and death. It can also cause hallucinations. All common drugs are easily detectable with ``drug test-cards{\crqq}, which are used during police checks around the the world. The Czech Republic is currently testing their utilization and is preparing legislation accordingly. Utilization of these tests during random checks could help to decrease the number of fatal road accidents and could help to decrease the number of impaired drivers on the roads.

Research plasticity of foundry sands
Macků, Martin ; Křístek, Jiří (referee) ; Rusín, Karel (advisor)
The subject of this thesis was to develop a comprehensive methodology for evaluating the plasticity of molding sand. This study was focused on four types of mixtures that are used in the foundry industry. For the evaluation of plasticity was important to provide an indicator of the deformation ability, calculation of deformation and logarithmic transformation for compression. Plasticity methodology was applied in this work only on the pressure effect. Studies of this issue can have a great influence on the production of correct forms due to the ability to withstand tension without breaking form.

Mechanisms of invasiveness and transcription regulation in cancer cells
Tolde, Ondřej
The mechanisms of invazivity and regulation of transcription of cancer cells Cancer originates in cells that overcome the control mechanisms of the organism. Cancer cells can be eventually released from the site of origin and spread through tissues. Cancer cells can acquire certain mechanisms that enable them to more effectively invade surrounding tissue or layers of other cells. The research on the migration of cancer cells is important for the understanding of the origin and spreading of metastases and consequently for anticancer therapy. In my Ph.D. work, I participated in the research of the properties of invasive metastatic cells. We compared non-invasive rat sarcoma cell line with a higly metastatic cell line derived from it. We showed that cells of the invasive cell line use amoeboid mode of migration, have upregulated Rho/ROCK signaling, and have accumulated actin and myosin at the leading edge. It is at the leading edge where the cells generate their traction forces. Cells of non-invasive cell line use mesenchymal mode of migration and generate forces mainly at their retracting end. We also compared two breast cancer cell lines derived from a single carcinoma. We showed that the more invasive cell line, derived from its parental line by neoplastic transformation, displayed elevated cytoskeletal...

Multimedia communication
Vondra, Zdeněk ; Horný, Stanislav (advisor) ; Skrbek, Jan (referee) ; Jurášková, Olga (referee)
Multimedia is a form of communication and sharing knowledge using synergic effect of parallel connected communication channels. Its main use is in producing communications products and services and in design of user interfaces. Main objective of this dissertation is to develop and create a model of multimedia communication for better understanding of the meaning and the purpose of using multimedia forms in communication process. The model will describe a system of elements and parameters of multimedia communication within the internal and external context. Another objective of this dissertation is to develop multimedia communication methodology that will be used for the design, development and evaluations of concepts of multimedia communication. The methodology will be created by applying the model of multimedia communication into the procedure structure. In theoretical way this dissertation is based on analysis of different definitions and approaches to the multimedia communications topic. This is followed by an analysis of communication theories, concepts of media, multimedia, delivery channels, and communication functions. The theoretical part is followed by the outcomes of the research in practice of four different fields of multimedia use. The knowledge gained is analyzed in the following parts in purpose of creating the model of multimedia communication and the methodology which is derived from the model. The methodology is further validated through case studies and the recommendations for further development are formulated. The model and the methodology of multimedia communication created in this dissertation present complex view on multimedia communication topic that is considered as a useful tool for meeting a specific communication purpose. Dissertation provides mechanics for use and study of multimedia communication and also defines the opportunities for further development of the methodology.

Ion attachment and ion emission of dust grains
Vyšinka, Marek ; Němeček, Zdeněk (advisor) ; Wild, Jan (referee)
Small dust grains could be found in many environments. Because of their size, their charge and the electric forces acting on them play an important role in their dynamics. The dust grain charge is influenced by many different processes. Among other methods, charging processes can be studied by trapping a single dust grain inside an electrodynamic quadrupole where it is put into specific environment (ion or electron beam, UV radiation). The progress of the charging process can be inferred from the changes in the grain charge. Our work contributed to the building of a new laboratory set-up for study of the charging processes. Specifically, a new Faraday cup for measurements and stabilization of the ion and electron gun currents is designed and its function verified. It solves the shortcomings of the previously used Faraday cups. Further, an amplifier for the ion gun current measurement is designed and constructed along with the design of digital stabilization of the current. The stabilization is neccesary for the interpretation of measurement results and its digitalization will allow more flexible adjustment and easier connection with the control computer. Finally, data acquired during the charging of dust grain with different ion species are evaluated in order to study the effect of different ions on surface...

Molecular factors of artherogenesis in chronic kidney disease with experimental model of chronic inhibition of Nitric Oxide Synthesis and its Effect of HMG-CoA reductase inhibitoin
Lecian, Dalibor ; Matouš, Bohuslav (advisor) ; Tesař, Vladimír (referee) ; Zadražil, Josef (referee)
The experimental part of the thesis covered the markers involved in nitric oxide deficiency model in rats. The analogue of arginine N-nitro- L -arginine-methyl ester ( L -NAME) was used. L -NAME administration resulted in sustained elevation of BP, decreased GFR, and in higher albuminuria compared to control animals. The administration of hypolipidemic drug - atorvastatin to Wistar rats was studied. The statin used caused lower albuminuria and prevented decreases in GFR in L -NAME rats without having an impact on hypertension. CAV1 protein expression was similar in all groups of rats. In contrast, VEGF expression and RhoA activity was increased in L -NAME-treated animals, and normalized with coadministration of atorvastatin. Clinical part of the thesis focused on the analysis of markers of oxidative stress in obese and non-obese patients with CKD and after kidney transplantation. The patients with CKD had elevated serum concentrations of AGEs, sRAGE and ADMA with the maximal concentrations of AGEs in the patients on hemodialysis. The successful kidney transplantation decreases the AGEs, sRAGE and ADMA concentrations but not to normal value according to general population. Patients with obesity exhibited lower concentrations of sRAGE in CKD as a protective factor for cardiovascular disease. Concentrations of...

T cells labelling by bimodal contrast agent for in vivo studies of stroke
Krijt, Matyáš ; Poljaková, Jitka (advisor) ; Kříž, Jan (referee)
Stroke is a serious brain injury, which causes sudden death or terminates in permanent neurological disability. Nowadays, tissue plasminogen activator (tPA) is used as the only effective treatment of stroke. One of the potential targets for novel therapy are T cells. Even though the explicit role of T cells in the pathogenesis of brain injury, amounts and timing of all T cell subtypes infiltrating into brain during the stroke still needs further investigation. The research in this field is complicated by the lack of efficient methods for in vivo cell tracking. Therefore the aim of this thesis was to develop a method of T cells labelling by MRI contrast agent in order to investigate T cells distribution in ischemic mice model using in vivo MR imaging. T cells were isolated from C57/BL6 mice in two step isolation protocol using gradient centrifugation and magnetic separation with the efficiency of 97 %. The isolated cells were labelled with 100 μg Fe/mL of Molday ION Rhodamine B contrast agent. The labelling efficiency after 17 hours of cells incubation was higher than 99 %. The labelled cells were cultured with CD3 and CD28 antibodies resulting into the 74 % viability of labelled T cells compared to 83 % viability of non labelled T cells. The labelled T cells were visualized by fluorescent...

Embrittlement of TiAl intermetalics induced by surface oxidation
Fukátková, Pavla ; Jan, Vít (referee) ; Dlouhý, Ivo (advisor)
This work aimed to study the effect of surface oxidation of TiAl intermetallic alloys, its fracture behavior and study the formation and stability of picked coatings that could prevent these phenomena. ?-TiAl alloy (Ti46Al7Nb) was examined by three different coatings (AlCr, AlCrN and AlCrNAg). Firstly, it was carried out short-term exposure to high temperature in an inert atmosphere for all coatings. Secondly, there were experiments of cyclic exposure to high temperature in normal atmosphere and isothermal high-temperature exposure in a normal atmosphere. During high-temperature experiments in normal atmosphere mass gain was measured and it was monitored a surface texture. Finally, the most promising coatings were chosen, and those were evaluated in bending strength.