<p>RNA-directed DNA methylation (RdDM) is a process by which epigenetic silencing is maintained at the boundary between genes and flanking transposable elements. In maize, RdDM is dependent on <i>Mediator of Paramutation 1 (Mop1</i>), a putative RNA dependent RNA polymerase. Here I show that although RdDM is essential for the maintenance of DNA methylation of a silenced <i>MuDR</i> transposon in maize, a loss of that methylation does not result in a restoration of activity of that element. Instead, heritable maintenance of silencing is maintained by histone modifications. At one terminal inverted repeat (TIR) of the element, heritable silencing is mediated via H3K9 and H3K27 dimethylation, even in the absence of DNA methylation. At the second TIR, heritable silencing is mediated by H3K27 trimethylation, a mark normally associated with somatically inherited gene silencing. I find that a brief exposure of high temperature in a <i>mop1</i> mutant rapidly reverses both of these modifications in conjunction with a loss of transcriptional silencing. These reversals are heritable, even in <i>mop1</i> wild type progeny in which methylation is restored at both TIRs. These observations suggest that DNA methylation is neither necessary to maintain silencing, nor is it sufficient to initiate silencing once it has been reversed. To leverage the specificity of our observations made at bench, I also performed a transcriptome analysis in <i>mop1</i> mutants under heat. I found that a substantial number of genes as well as a subset of TEs are reactivated in <i>mop1</i> mutants under heat, which is consistent with the effects I observed on <i>MuDR</i>. Interestingly, I found that <i>mop1</i>-specific reactivation of TEs is closely correlated with changes in expression of nearby genes, most of which are involved in metabolic transportation and sensing. This suggests that one function of <i>MOP1</i> is to prevent inappropriate expression of genes in this pathway when they are close to TEs. Taken together, my work will provide an opportunity to better understand the causes and consequences of TE silencing and reactivation, as well as the effects of TEs on gene regulation under stress conditions.</p>

The objectives of the submitted diploma work are to give an overview of the therapeutics{\crq} psychotherapy styles and their feelings about the psychotherapy in general. The work also shows the circumstances which directed them to be the therapeutics. In connection with that the work analyzes also the evolution and, above all, the present situation in the psychotherapy in the Czech Republic. Finally the work summarizes therapeutics{\crq} opinion about the integration in the psychotherapy according to the style they practicing. Theoretical part of the diploma work introduces twelve psychotherapy styles which are commonly use in the Czech Republic. All styles are presented by short historical development and the practical application in our country. Information for the practical part of the diploma work were obtained by interviewing the therapeutics, the interviews were recorded, consequently rewrote and authorized by the therapeutics. The main contribution of the diploma work is the comparison of the therapeutics{\crq} opinions, partly consistent but some time also very different, what is appeared in the interviews. The interviews it self were spitted to the four groups, according to the topics: Knowledge and experiences of the therapist, Common active factors and the efficiency in the psychotherapy, Integration in the psychotherapy and Critique of the psychotherapy.

This dissertation is dealing with the town of Telč and its way of living in the first half of the 20th century. The research is focused on the thorough analysis of local authorities from the social and occupational point of view, territorial origin and location of residence its various fellows. The main purpose of this is to idicate the changes which coincided with the influence of nationwide political, social and economic changes. The illustration of six Telč´s families with various professions charts their share which affected the social, cultural and public life of the town. The aim is to get an integral view of this period, therefore the grammar school staff have been included, because of their participatory role in local authorities and social life as well. Municipal and school celebrations have been included to illustrate the cultural backround of provincial town in the first half of the 20th century.