Tolerance limits and survival potential of methanogenic archaea from Siberian permafrost under extreme living conditions

The doctoral thesis was part of the ongoing research project “Tolerance limits of microbial life in terrestrial permafrost” in the scope of the DFG (Deutsche Forschungsgemeinschaft) Priority Program “Mars and the Terrestrial Planets” WA 1554/1-2. In this project, special attention was paid to the survival potential of methanogenic archaea in Siberian permafrost. Field research and sampling were carried out during the expedition Lena Delta 2004 (Samoylov Island, Siberia, Russia). The work was conducted at the Alfred Wegener Institute for Polar and Marine Research, Research Unit Potsdam and is presented as a Ph.D. thesis at the University of Potsdam, Institute of Biochemistry and Biology. The thesis is composed of an introduction and four main chapters (2-5), followed by synthesis and conclusions. In the first chapter, an introduction of the research topic, the main objectives of this work, study site description and an overview of the publication is given. The main chapters consist of four manuscripts that represent self-contained units which are field on a common thread. Chapter 2 is in preparation for submitting and Chapter 4 has been submitted for publication to various international journals, whereas Chapter 3 and 5 are published already (s. 1.5). A synthesis of the four research articles is given in Chapter 6, including the outline of the basic findings aswell as major conclusions and future perspectives

The Russian middle class families on the school market in Helsinki metropolitan region : ethnicity vs social class

Based on 20 semi-structured interviews with Russian parents living in Helsinki metropolitan area, this Thesis investigates interrelation of ethnicity and belonging to middle class in the context of free school choice. Using, on the one hand, the theory of social reproduction by Bourdieu, and, on the other, various studies on how immigrant parents cope with school choice, I aim to uncover whether immigrant background of the interviewees undermines the positive effect of their social class on school choice. Pierre Bourdieu’s theory of social reproduction is a backbone for this study. According to Bourdieu, social class, family environment and education are closely interrelated. In particular, education plays the pivotal role in social position perpetuation and preservation since it shapes the cultural capital which volume reflects the social position of its holder. Furthermore, this reproduction is facilitated in school and during the process of school choice since families with the highest amount of cultural capital can make the most balanced choices whereas those with little volume of cultural capital are not capable to evaluate their choice opportunities properly. In this sense, the middle class families have raised to their social position through cultural capital of which education is an important part. That is why the middle class families are the most interested in making the best possible choices in order to secure their social position. Such theoretical paradigms as habitus, cultural capital, linguistic capital, economic capital and social capital, coined by Bourdieu, are referred to in this Thesis. On the other side, many scholars argue that free school choice increases the gap in education between social classes, making families with immigrant background especially vulnerable. They emphasize that free school choice can lead to yet another layer of social stratification since white and wealthy try to maintain their status by ignoring or leaving schools with social mix and thus distance themselves from the lower status groups. As a result, immigrant families are concentrated in particular - usually dilapidated - neighborhoods and possess little, if any, knowledge or skills to exercise school choice. Consequently, the so-called 'school segregation' occurs. Additional effects of this school separation are obstacles on the way of establishing daily contacts with the natives which, in its turn, hampers language proficiency necessary for educational progress. This Thesis is focused on two implications within school choice theory: immigrant background and middle class. The interviewees – Russian immigrants on the school market in Helsinki, belong to both of these groups. The main research question is whether immigrant background undermines the positive effect by middle class created on the school market. A set of sub-questions is developed to make analysis in-depth and coherent. Based on 20 semi-structured interviews, I group the narratives into mutual 'themes'. While developing the analysis, I divide all the themes into factors that have impact on school choice and lay within the families (gender, cultural capital etc.) and those that are inferior to the families (for instance, school reputation, distance from home etc.). In the former case I elaborate if the middle class families of the Russian origin are able to make use of their personal characteristics while carrying out the task of school evaluation. In the latter case I compare the way the parents evaluate the inferior characteristics with previous research on immigrants and social class in the context of free school choice. By this, I am trying to uncover if the reasoning of the interviewees bears the patterns of either immigrants’ or middle class representatives. According to the findings of this study, Russian middle class families in Helsinki metropolitan area are capable to wisely use their cultural capital in order to make the best possible (in their view) choice on the local school market. Regardless particular constraints that occur due to context-specific knowledge or lack of linguistic capital, the immigrant background of the interviewees does not seriously undermine the privileges created by their middle class position on the local school market. In particular, the interviewees show high level of interest in educational progress of their children, have relatively high educational standards, are trying to be as inclined in school life of their children as they can and generally attribute high level of importance to everything connected with schooling

Physiology of taste perception

Ústav hygieny 3. LF UKDepartment of Hygiene 3FM CU3. lékařská fakultaThird Faculty of Medicin

Impact of gas storage on reservoir rocks : long-term study to investigate the effects on mineral content and fluid chemistry

To study the effects of gas storage, long-term autoclave experiments with rock cores originating from a natural gas reservoir and brines taken from a gas well were conducted at 40 bar and 80o C in a CO_{2} atmosphere. While the main mineral composition of the sandstones was not affected due to CO_{2} exposure over a period of 31 months, the dissolution of rock-forming minerals such as feldspar, quartz or pore-filling anhydrite and calcite was noted. Changes in the brine composition were also detected. A release of iron and total organic carbon (TOC) from the rock samples to the saline fluid was observed. Temporary changes in the acetic acid concentration might have contributed to the dissolution processes. Precipitation and dissolution of minerals in sandstones were mostly related to diagenetic fluid-rock reactions and CO_{2} exposure, but in general the impact of CO_{2} on rock composition was only minor

Methodology for Creating a Geographic Information System for Transport Infrastructure Facilities

This study examines the methodology for creating a geographic information system of transport infrastructure objects - from obtaining initial data to storing the data itself. The article defines the classification of objects in the transportation system, the procedure for collecting and processing initial data, as well as the sequence of data processing for transmission to the GIS environment. A study was conducted on the dependence of response time on the current number of elements in a database table with indexed and un-indexed data. Until about the 1000th element, it was determined that the sampling rate is higher by "direct search", but after that, a smooth linear growth begins to a sharp peak and a nonlinear increase in search time. Thus, the support of database management system functions for working with spatial data is important for its functioning in the context of geometric data aggregation tasks

Common dace (Leuciscus leuciscus) - A new host of the myxozoan fish parasite, Myxobolus elegans (Cnidaria: Myxozoa) - Short communication

This paper reports the detection of the myxozoan species Myxobolus elegans Kashkovsky 1966 in common dace (Leuciscus leuciscus) that has not been previously listed as its host. The problem of differentiation of phenotypically similar Myxobolus species is addressed. During parasitological survey of common dace from the desalinated part of the Gulf of Finland at the city of Sestroretsk, Russia, numerous oval-shaped plasmodia, 0.2-0.4 mm in size, filled with Myxobolus spores were found on the gills. Pear-shaped myxospores were 15.4 (14.8-16.0) x 10.2 (9.6-10.9) mu m in size with a rib on each valve. On the basis of spore morphology, the species appeared to be similar to M. elegans and Myxobolus hungaricus Jaczo, 1940. In order to identify the species, molecular genetic analysis was performed, and the species was identified on the basis of morphological characteristics and 18S rDNA data. The results obtained indicate that the Myxobolus species observed on the gills of dace is M. elegans. Thus, common dace is another valid host of M. elegans besides the type host, ide (Leuciscus idus)

Media Representation of Religiousness in Modern Russian Society

The study is devoted to a relevant topic – the analysis of the media representation of religiousness in modern Russian society based on media materials. In the scientific literature, there are various assessments of religious media discourse: some authors argue that the media reflect and others that the media distort the real situation. The study presents the idea that the ambiguity of assessments of the level of religiousness and its features is only partially explained by ideological differences between the discourses. To a large extent, such ambiguity is formed as a consequence of the instability of religious identification. Media materials note the superficial nature of religious consciousness, which is evidenced by the low level of churching, predominantly ceremonial nature of religious practice, and shallow knowledge of the essence of dogma. However, according to the authors of the study, an insufficiently high level of religious culture should not be assessed as a profanation of faith. The analysis of the texts published in Russian printed and online media shows that the image of religiousness in the secular segment of the information field differs from the media of different political orientations