81 resultados para Töpffer, Rodolphe, 1799-1846.

em Helda - Digital Repository of University of Helsinki


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The Forest devil. Businessman Erik Johan Längman (1799 1863) in the transition of economic system In Finnish historiography, Erik Johan Längman (1799-1863) bears a bad reputation of his own level: a mean, profit-seeking businessman who did not care too much about methods in his operations. Although little known, Längman has been praised as one of the pioneers of modern industry in the Grand Duchy of Finland, which belonged to the Russian Empire. From the mid 1830s Längman owned iron mill and several sawmills around the country. The growing demand of the markets in the 1830s, especially in Great Britain, marked a strong stimulus to Finnish lumber industry. At the same time claims for stricter rule over the sawmill industry were raised by high officials. The momentum of the conflict, the Forest Act of 1851, brought an end to illegal overproduction. In this biography, particular emphasis is laid on the entrepreneurial behaviour of Längman, but also on the effect the entrepreneurs had on the Crown s policies. On the other hand, how did the limitations imposed by the Crown guide the actions of the sawmill owners? The solutions adopted by the sawmill owners and the manoeuvring of the government are in a constant dialogue in this study. The Finnish sawmill industry experienced a major change in its techniques and methods of acquiring timber during the 1830s. Längman particularly, with his acquisition organisation, was able to find and reach faraway forests with unexpected results. The official regulating system with its strict producing quotas couldn t follow the changes. When the battle against the sawmill industry really started on, in 1840, it didn t happen for the benefit of iron industry, as argued previously, but to save Crown forests from depletion. After the mid 1840s Längman and the leader of the Finnish nationalistic movement, J. V. Snellman questioned the rationality of the entire regulation system and in doing so they also posed a threat against the aristocratic power. The influential but now also badly provoked chairman of the economic division of senate, Lars Gabriel von Haartman, accused the sawmill-owners harder than ever and took the advantage of the reactionary spirit of imperial Russia to launch the state forest administration. Längman circumvented the conditions of privileges, felled Crown forests illegally and accusations were brought against him for destroying his competitors. The repeated conflicts spoke primarily about a superior business idea and organisational ability. Although Längman spent his last years mostly abroad he still had interests in Finnish timber business when the liberation of sawmill-industry was established, in 1861. Surprisingly, the antagonism around the Crown forests continued, probably even more heated.

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Tutkielma käsittelee kuvataideyleisön muotoutumista Suomen Taideyhdistyksen piirissä 1800-luvun puolivälissä sosiaalihistoriallisesta näkökulmasta. Tärkein lähdemateriaali on Suomen Taideyhdistyksen arkisto, jonka avulla tarkastellaan laajemmin yhdistyksen ideaa, sen jäsenyyttä, maanlaajuista jäsenkartuntaa ja johtokunnan taiteen kannattajiin suuntaamaa missiota toiminnan alkuvuosikymmeninä. Yhdistyksen helsinkiläinen jäsenistö vuosina 1846−1865 on luokiteltu kymmeneen luokkaan jäsenluettelossa annettujen nimikkeiden perusteella. Lähdeaineiston ja sen pohjalta tehdyn luokittelun avulla analysoidaan pääkaupungin jäsenkuntaa ja sen suhdetta koko maan jäsenistöön. Jäsenkunnasta nostetaan esille myös joitakin kiinnostavia yksilöitä. Tutkielman pääasiallinen teoreettinen viitekehys on Sosiologi Everett Rogersin malli innovaatioiden diffuusiosta. Taiteen kannattaminen uutena ideana vertautuu tutkielmassa uuteen keksintöön ja sen leviämiseen. Tutkielmassa osoitetaan, että kuvataiteen saadessa 1800-luvun kuluessa uudenlaisia merkityksiä myös taiteen yleisö määrittyi uudelleen. Vuonna 1846 perustetulla Suomen Taideyhdistyksellä oli tässä ratkaiseva ja aktiivinen rooli. Taiteen kannattajakunnan ydin oli Helsingissä, jossa vaikutti yhdistyksen lähinnä korkeista virkamiehistä ja professoreista koostunut johtokunta. Taideyhdistyksen toiminnan vakiintuessa taiteen kannattamisen idea levisi ja sitä levitettiin yhä useammille paikkakunnille sekä laajempiin kansankerroksiin. Yhdistyksen jäsenkuntaan liittyi lähinnä säätyläistöä, mutta taidenäyttelytoiminta tavoitti myös alempia yhteiskuntaluokkia. Taideyhdistyksen helsinkiläisessä jäsenkunnassa virkamiehistön rooli oli suuri. Alkuvaiheessa liittyneet yhteiskunnalliselta statukseltaan korkeat henkilöt saivat hallitsijan vakuuttumaan toiminnan luotettavuudesta. Taiteen kannattajakunta muodostui kuitenkin kasvavassa määrin alemmasta virkamiehistöstä ja elinkeinojen harjoittajista. Merkittävä osuus oli myös Keisarillisen Aleksanterinyliopiston opettajilla ja siellä tutkinnon suorittaneilla. Tärkein taiteen pääkaupunkilaista kannattajakuntaa yhdistänyt sosiaalinen viitekehys olikin yliopisto. Sen antama koulutus, sivistys ja henkinen pääoma olivat taustalla suurimmalla osalla yhdistykseen Helsingissä liittyneistä. He kuuluivat pääsääntöisesti aktivoituvaan sivistyneistöön, joka syntyi sääty-yhteiskunnan vanhojen rakenteiden hämärtyessä ja yliopistotutkintojen saadessa yhä suurempaa yhteiskunnallista merkitystä.

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From the Finnish Art Society to the Ateneum: Fredrik Cygnaeus, Carl Gustaf Estlander and the Roles of the Art Collection My dissertation deals with the Finnish Art Society and the development of its collection in the evolving field of the visual arts from the foundation of the society in 1846 to its exhibition in the Ateneum, a palace of art that was opened to the public in Helsinki in 1888. The main questions that it addresses are why and how the collection came into being, what its purpose was and what kind of future prospects were projected for it in the rapidly evolving field of the visual arts. I have examined the subject of my study from the perspectives of institutional history, the organisation of the field of art and the history of art collections. The prisms through which I have viewed the subject are the history of museums in Europe, the written history of art, the art association movement and the organisation of art education in relation to an ideology of enlightenment. Thus the activities of the Finnish Art Society are here mirrored for the first time in a wider context and the history of its collection located on the map of European collections. My research shows that the history of the collection of the Finnish Art Society initially depended on certain players in the visual arts and their particular leanings. The most important of these custodians were two long-serving chairmen of the society, Fredrik Cygnaeus (1807 1881) and Carl Gustaf Estlander (1834 1910). When the foundations for art activities had been laid through the establishment of the society, Cygnaeus and Estlander began to plan how the field of art might be moulded so as to improve the level of training for artists and to improve the quality of the collections and the opportunities for their display. Cygnaeus campaigned for the establishment of the Finnish Fine Arts Academy, while Estlander saw opportunities to combine the visual and applied arts. The findings of my research bring new information about the history of the collection of the Finnish Art Society, its profile, the professional abilities of those who were mainly responsible for developing it and the relationship between it and plans for reforming art education. The major findings are connected with the position of the collection in the field of art at different stages of its development. Despite the central monopoly of the Finnish Art Society in the field of art, the position of the collection was closely bound up with leading players in the field of art and their personal interests. This subservience also created an impediment to its full-blown enhancement and purposeful profiling, and it remained evident for a long time when the collection was seeking its own place in the Finnish art world.

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Professor Knud Lyne Rahbek was a novelist, playwright, poet, magazine editor, journalist, socialite person, host of the Bakkehus , historian, theatre manager, translator, publisher etc., but his versatility either side of 1800 is better known than read and more despised than understood. In terms of methodology, the thesis is based on biographical, historical and philological research, while at the same time making use of formalistic and close reading methods. This study begins and ends with 7th of February 1800, when Kamma and Knud Lyne Rahbek join the exiled P.A. Heiberg at the inn near Frederiksberg Castle. What falls between is an interpretation of Rahbek s works in the service of democracy, human rights and freedom of the press as a pragmatic navigation between activities - both subversive and legitimate. Posterity mistook this range as mere spinelessness, and Rahbek was relegated to the literary and historical margins as an anachronism and as a jack of all trades, who did not know what he really wanted and therefore flitted about in so many fields just to be present. But Rahbek s problem was not one of standpoint, but rather how to find a balance between totalizing attitudes and confrontations between rebellious idealism and deep-rooted absolutism, without foregoing his belief in enlightenment, humanism and tolerance. In this way, and also through his personal conduct, which at that time was seen as jovial bonhommie, he made his contribution to the development of modern democratic Denmark in the full awareness of a popular, peaceful and down-to-earth community. Rahbek s principal work about the event of the French Revolution, which provides the focus for the above, is Camill og Constance. Et Revolutions Skilderie (1799). For today s reader, the novel about the revolution is an obvious example of a historical novel, as it does not only provide fictionalized information about past events placing them in a generally accepted perspective of historical development, but also gives the characters qualities, which, in Rahbek s words, allows the real events to influence the fictional characters. From this point of view, the novel of the revolution has shifted the benchmark for the first real historical novel on the European literary scene back by fifteen years. Lacking the aura so easily foisted on fearless iconoclasts or tragic losers, Rahbek s contribution may seem modest in spite of its enormous volume; but only when it is not evaluated in its full context, which is the development of Denmark towards an international democratic society.

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This is a case-study of students well-being studying in Sibelius Upper Secondary School which has got a special educational task in dance and music. The first purpose of this study is to analyse the students well-being, motivation, studying satisfaction and try to find out what kind of problems the students meet when studying in Upper Secondary School. The second purpose of this study is to try find means in counselling to help students in their Upper Secondary School Studies. The data were gathered in three parts. The first questioning was based on Allardt s (1976; 1998) well-being theory. In this questioning (N = 187) the students described their satisfaction in having (material things), loving (social relationships) and being (free time). The second data was collected by interviews (N = 19). The third data is a follow-up questioning (N = 10) for graduated students. The whole data was analysed with qualitative methods. The gathered qualitative data were compared with the quantitative data gathered by the National Institute for Health and Welfare. Results of this study indicate that the students in this case-study are mainly satisfied with their well-being, social and material things in their studying environment including counselling and teaching. The research results show that some of the students are exhausted due too muchtime spent in studying. This was verified also in the quantitative data gathered by the National Institute for Health and Welfare. These students suffer for the lack of free time and rest. Students who are motivated and have reached the autonomous way of studying do better in their Upper Secondary School Studies than those who study in unautonomous way.A quite wide range of students tend to make individual studying programmes and spend four or more years in Upper Secondary School instead of the three year programme. The individual programme gives them more time for practicing their special skills in the field of the school s special educational task and to give themselves more time for studying the basic subjects of the Upper Secondary School. Some of the students who tend to take extra years in Upper Secondary School have difficulties in their studying skills and are unsure of their studying motivation. The competition among students in Upper Secondary School with the special educational task causes stress and exhaustion for some of the studied students. These students have difficulties with integrating themselves into the social environment. For the other students the school s social environment works as a motivator for their studies and increases their well-being in their studies. According to the results of the follow-up questioning in this study the students value most the network with the other students they made while studying at the Sibelius Upper Secondary School. According to this study the students would need more counselling in all stages of their Upper Secondary School Studies. The autonomous students do quite well in their studies despite of the small amount of given counselling. They would also need more counselling in planning their further studies after Upper Secondary School. The biggest challenges to student counselling in Sibelius Upper Secondary School are helping the students to find their individual ways of studying and helping them to learn the ways of autonomous studying skills. Keywords: Upper Secondary School with a special educational task, well-being, talent, Upper Secondary School, Young person in Upper Secondary School, motivation, counselling, studying

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The research examines the process by which a sense of belonging to Finnish society is constructed among women of Russian and Estonian background who are multiply marginalised in Finnish society. It does so by analysing the encounters between their nationality and 'being Finnis'. Attention is focused on the question of what kind of "journey" they take after moving to Finland, how a sense of belonging is constructed especially along the paths followed in education and at work, and what kind of agency is available to them. The thesis is connected with post-colonial research and also draws from studies on citizenship and nationality as well as the social structures of interaction, when analysing careers. As the educational system forms the most central context of the research, the work is also focused on educational sociology. The research methodology includes life history and a narrative approach. The raw data is from thematic interviews concerning the life experiences of women of immigrant backgrounds. They were studying in Finland to be practical nurses or to complete Bachelor of Social Service degree. According to the study, the women had been encountered as alien, strange, and carrying a shade of "otherness". The experience of inclusion in Finnish communities and society turned out to be conditional, an inclusion based on the notion of a citizen worker, which is defined by national needs. The person from abroad is placed in the position of someone who fills gaps in the services of the welfare state. The choice of education in the care sector and the overall necessity of obtaining Finnish education turned out to be socially directed. Gendered structures of education and working life were found to act as a frame in which the decisions of the immigrant women were made. Although national education policy emphasis as an orientation to global labour markets, the immigrant student is placed above all in the position of an object to be made suitable for the Finnish labour market. Citizenship, a goal of education, requires consent to being "socialised" into Finnish society as well as learning to be Finnish. One s only option to negotiate appearing suitable as a member is to construct oneself into someone who adopts Finnish and Western cultural values, values which favour individuality. However, Finnish education is a resource to Finnishness. Finnish education enables a sense of being Finnish, and empowers the job applicant for example, and in addition to providing cultural, human and social capital strengthen inclusion as well. The study confirms the view that the encounter of an immigrant is still characterised by its colonial nature. It shows that encounters with Finns and Finnish society place the person of immigrant background, even one receiving a Finnish education, in the position of "the other". The journey as an immigrant continues. The immigrant has access only to certain predefined subject positions, which limits agency. When categorised as an immigrant, one becomes a per-son who is different and "other", while the sense of belonging as a member of Finnish society without conditions appears to be somewhat unreachable. Yet, new arrivals are capable of acting change. An immigrant woman can challenge the positions offered to her and present herself as strong. Her life story has often included struggle, and she has the fortitude strength to change her circumstances. Key words: life story, post-colonial encounter, nationality, citizenship, the career of immi-grant, position, agency

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The objective of the dissertation was to determine the concept of sustainable development according to current understanding and to analyze the structuration of sustainable daily life and how it varies between different groups. The present dissertation is both a literature-based theoretical study and data-based empirical research. The theoretical framework of the study was a greated model of the Structuration of Sustainability in Everyday Life. The model is based on a synthesis of Giddens Theory of Structuration (1984), Spaargaren JA van Vliet's Theory of Consumption as Social Practices (2000) and principles of sustainable development. According to the model created, sustainable everyday life is generated in a context of internal and external factors compromising the interests of ecosystems, society and business. The literature used in the thesis included international and national statements on sustainable development and research into sustainability and the transition to sustainable societies. The data were collected at Helsinki Metropolia University of Applied Sciences. The discretionary sample consisted of students of social services (n = 210) and were collected using the semantic differential technique. The data were analyzed using quantitative and qualitative methods. The results showed that the value placed on ecological, economic and social sustainability increased with age. Activity in non governmental organizations was associated with the acceptance of sustainable development as a whole and especially with global responsibility. Women's everyday life promoted sustainability more than men´s. People living in Helsinki had more sustainable ways of living than those living in the surrounding municipalities because of greater recycling and the low importance given to ownership. Prefering vegetarian food turned out to be a real opportunity for a more sustainable way of living because there were few barriers identified. Contradictory human behavior occurred when advanced sustainable consumer were ready to risk their health. The importance of communality was high and it was considered an aspect of health. The most significant obstacles to sustainable development in daily life were high costs, lack of knowledge and busyness. Similar attitudes towards sustainable development translate into different people´s behavior, which indicates complexities of the behaviour change in the context of sustainable development. The role of non governmental organizations is significant in increasing global responsibility. Education presents an opportunity to increase sustainability, but there are challenges to face from system thinking and in understanding entities in a state of transition towards sustainable everyday life. The responsibility of policy makers is paramount because high costs create a barrier to a sustainable way of living. The implementation of the concept of sustainable development should be focused on the planetary ethics which cover humans, animals, plants and ecosystems. Keywords: Sustainable development, sustainable thinking, behaviour change  

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The main purpose of the research was to illustrate chemistry matriculation examination questions as a summative assessment tool, and represent how the questions have evolved over the years. Summative assessment and its various test item classifications, Finnish goal-oriented curriculum model, and Bloom’s Revised Taxonomy of Cognitive Objectives formed the theoretical framework for the research. The research data consisted of 257 chemistry questions from 28 matriculation examinations between 1996 and 2009. The analysed test questions were formulated according to the national upper secondary school chemistry curricula 1994, and 2003. Qualitative approach and theory-driven content analysis method were employed in the research. Peer review was used to guarantee the reliability of the results. The research was guided by the following questions: (a) What kinds of test item formats are used in chemistry matriculation examinations? (b) How the fundamentals of chemistry are included in the chemistry matriculation examination questions? (c) What kinds of cognitive knowledge and skills do the chemistry matriculation examination questions require? The research indicates that summative assessment was used diversely in chemistry matriculation examinations. The tests included various test item formats, and their combinations. The majority of the test questions were constructed-response items that were either verbal, quantitative, or experimental questions, symbol questions, or combinations of the aforementioned. The studied chemistry matriculation examinations seldom included selected-response items that can be either multiple-choice, alternate choice, or matching items. The relative emphasis of the test item formats differed slightly depending on whether the test was a part of an extensive general studies battery of tests in sciences and humanities, or a subject-specific test. The classification framework developed in the research can be applied in chemistry and science education, and also in educational research. Chemistry matriculation examinations are based on the goal-oriented curriculum model, and cover relatively well the fundamentals of chemistry included in the national curriculum. Most of the test questions related to the symbolism of chemical equation, inorganic and organic reaction types and applications, the bonding and spatial structure in organic compounds, and stoichiometry problems. Only a few questions related to electrolysis, polymers, or buffer solutions. None of the test questions related to composites. There were not any significant differences in the emphasis between the tests formulated according to the national curriculum 1994 or 2003. Chemistry matriculation examinations are cognitively demanding. The research shows that the majority of the test questions require higher-order cognitive skills. Most of the questions required analysis of procedural knowledge. The questions that only required remembering or processing metacognitive knowledge, were not included in the research data. The required knowledge and skill level varied slightly between the test questions in the extensive general studies battery of tests in sciences and humanities, and subject-specific tests administered since 2006. The proportion of the Finnish chemistry matriculation examination questions requiring higher-order cognitive knowledge and skills is very large compared to what is discussed in the research literature.

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Physicochemical characterization of freshwater samples from Finland, Sweden, the Netherlands, and Spain revealed that water hardness and pH decreased and the quantity and quality of humic substances changed considerably in this geographical series from south to north. Since the ambient water chemistry may affect the availability of chemicals, the total aqueous concentration of a chemical may be insufficient to predict the bioconcentration, subsequent biological response, and thus risk. In addition, organisms could be affected directly by water quality characteristics. In this context the main objective of this thesis was to investigate the bioavailability of selected ecotoxicologically relevant chemicals (cadmium, benzo(a)pyrene, and pyrene) in various European surface waters and to show the importance of certain water chemistry characteristics in interpreting the bioavailability and toxicity results. The bioavailability of cadmium to Daphnia magna was examined in very soft humic lake water. Humic substances as natural ligands decreased the free and bioavailable proportion of cadmium in soft lake water. As a consequence the uptake rate and the acute toxicity decreased compared with the humic-free reference. When the hardness of humic lake water was artificially elevated, the acute toxicity of cadmium decreased, although the proportion of free cadmium increased. The decreased bioavailability of cadmium in hard water was a result of effective competition for uptake by the hardness cations, especially calcium ions. The protective role of humic substances and water hardness against cadmium toxicity was also observed in Lumbriculus variegatus, although D. magna was more sensitive to cadmium. The bioavailability of two polycyclic aromatic hydrocarbons (PAHs), pyrene and benzo(a)pyrene, was studied in European surface waters of varying water chemistry. Humic substances acted as complexing ligands with both PAHs, but the bioavailability of the more lipophilic benzo(a)pyrene to D. magna was affected more by humic substances than that of pyrene. In addition, not only the quantity of humic substances, but also their quality affected the bioavailability of benzo(a)pyrene. Nevertheless, the humic substances played a protective role in the photo-enhanced toxicity of pyrene under UV-B radiation. Water hardness had no effect on pyrene toxicity. Results indicate that the typical physicochemical characteristics of boreal freshwaters should be considered carefully in local and regional risk assessment of chemicals concerning the Fennoscandian region.

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Lead contamination in the environment is of particular concern, as it is a known toxin. Until recently, however, much less attention has been given to the local contamination caused by activities at shooting ranges compared to large-scale industrial contamination. In Finland, more than 500 tons of Pb is produced each year for shotgun ammunition. The contaminant threatens various organisms, ground water and the health of human populations. However, the forest at shooting ranges usually shows no visible sign of stress compared to nearby clean environments. The aboveground biota normally reflects the belowground ecosystem. Thus, the soil microbial communities appear to bear strong resistance to contamination, despite the influence of lead. The studies forming this thesis investigated a shooting range site at Hälvälä in Southern Finland, which is heavily contaminated by lead pellets. Previously it was experimentally shown that the growth of grasses and degradation of litter are retarded. Measurements of acute toxicity of the contaminated soil or soil extracts gave conflicting results, as enchytraeid worms used as toxicity reporters were strongly affected, while reporter bacteria showed no or very minor decreases in viability. Measurements using sensitive inducible luminescent reporter bacteria suggested that the bioavailability of lead in the soil is indeed low, and this notion was supported by the very low water extractability of the lead. Nevertheless, the frequency of lead-resistant cultivable bacteria was elevated based on the isolation of cultivable strains. The bacterial and fungal diversity in heavily lead contaminated shooting sectors were compared with those of pristine sections of the shooting range area. The bacterial 16S rRNA gene and fungal ITS rRNA gene were amplified, cloned and sequenced using total DNA extracted from the soil humus layer as the template. Altogether, 917 sequenced bacterial clones and 649 sequenced fungal clones revealed a high soil microbial diversity. No effect of lead contamination was found on bacterial richness or diversity, while fungal richness and diversity significantly differed between lead contaminated and clean control areas. However, even in the case of fungi, genera that were deemed sensitive were not totally absent from the contaminated area: only their relative frequency was significantly reduced. Some operational taxonomic units (OTUs) assigned to Basidiomycota were clearly affected, and were much rarer in the lead contaminated areas. The studies of this thesis surveyed EcM sporocarps, analyzed morphotyped EcM root tips by direct sequencing, and 454-pyrosequenced fungal communities in in-growth bags. A total of 32 EcM fungi that formed conspicuous sporocarps, 27 EcM fungal OTUs from 294 root tips, and 116 EcM fungal OTUs from a total of 8 194 ITS2 454 sequences were recorded. The ordination analyses by non-parametric multidimensional scaling (NMS) indicated that Pb enrichment induced a shift in the EcM community composition. This was visible as indicative trends in the sporocarp and root tip datasets, but explicitly clear in the communities observed in the in-growth bags. The compositional shift in the EcM community was mainly attributable to an increase in the frequencies of OTUs assigned to the genus Thelephora, and to a decrease in the OTUs assigned to Pseudotomentella, Suillus and Tylospora in Pb-contaminated areas when compared to the control. The enrichment of Thelephora in contaminated areas was also observed when examining the total fungal communities in soil using DNA cloning and sequencing technology. While the compositional shifts are clear, their functional consequences for the dominant trees or soil ecosystem remain undetermined. The results indicate that at the Hälvälä shooting range, lead influences the fungal communities but not the bacterial communities. The forest ecosystem shows apparent functional redundancy, since no significant effects were seen on forest trees. Recently, by means of 454 pyrosequencing , the amount of sequences in a single analysis run can be up to one million. It has been applied in microbial ecology studies to characterize microbial communities. The handling of sequence data with traditional programs is becoming difficult and exceedingly time consuming, and novel tools are needed to handle the vast amounts of data being generated. The field of microbial ecology has recently benefited from the availability of a number of tools for describing and comparing microbial communities using robust statistical methods. However, although these programs provide methods for rapid calculation, it has become necessary to make them more amenable to larger datasets and numbers of samples from pyrosequencing. As part of this thesis, a new program was developed, MuSSA (Multi-Sample Sequence Analyser), to handle sequence data from novel high-throughput sequencing approaches in microbial community analyses. The greatest advantage of the program is that large volumes of sequence data can be manipulated, and general OTU series with a frequency value can be calculated among a large number of samples.

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New stars form in dense interstellar clouds of gas and dust called molecular clouds. The actual sites where the process of star formation takes place are the dense clumps and cores deeply embedded in molecular clouds. The details of the star formation process are complex and not completely understood. Thus, determining the physical and chemical properties of molecular cloud cores is necessary for a better understanding of how stars are formed. Some of the main features of the origin of low-mass stars, like the Sun, are already relatively well-known, though many details of the process are still under debate. The mechanism through which high-mass stars form, on the other hand, is poorly understood. Although it is likely that the formation of high-mass stars shares many properties similar to those of low-mass stars, the very first steps of the evolutionary sequence are unclear. Observational studies of star formation are carried out particularly at infrared, submillimetre, millimetre, and radio wavelengths. Much of our knowledge about the early stages of star formation in our Milky Way galaxy is obtained through molecular spectral line and dust continuum observations. The continuum emission of cold dust is one of the best tracers of the column density of molecular hydrogen, the main constituent of molecular clouds. Consequently, dust continuum observations provide a powerful tool to map large portions across molecular clouds, and to identify the dense star-forming sites within them. Molecular line observations, on the other hand, provide information on the gas kinematics and temperature. Together, these two observational tools provide an efficient way to study the dense interstellar gas and the associated dust that form new stars. The properties of highly obscured young stars can be further examined through radio continuum observations at centimetre wavelengths. For example, radio continuum emission carries useful information on conditions in the protostar+disk interaction region where protostellar jets are launched. In this PhD thesis, we study the physical and chemical properties of dense clumps and cores in both low- and high-mass star-forming regions. The sources are mainly studied in a statistical sense, but also in more detail. In this way, we are able to examine the general characteristics of the early stages of star formation, cloud properties on large scales (such as fragmentation), and some of the initial conditions of the collapse process that leads to the formation of a star. The studies presented in this thesis are mainly based on molecular line and dust continuum observations. These are combined with archival observations at infrared wavelengths in order to study the protostellar content of the cloud cores. In addition, centimetre radio continuum emission from young stellar objects (YSOs; i.e., protostars and pre-main sequence stars) is studied in this thesis to determine their evolutionary stages. The main results of this thesis are as follows: i) filamentary and sheet-like molecular cloud structures, such as infrared dark clouds (IRDCs), are likely to be caused by supersonic turbulence but their fragmentation at the scale of cores could be due to gravo-thermal instability; ii) the core evolution in the Orion B9 star-forming region appears to be dynamic and the role played by slow ambipolar diffusion in the formation and collapse of the cores may not be significant; iii) the study of the R CrA star-forming region suggests that the centimetre radio emission properties of a YSO are likely to change with its evolutionary stage; iv) the IRDC G304.74+01.32 contains candidate high-mass starless cores which may represent the very first steps of high-mass star and star cluster formation; v) SiO outflow signatures are seen in several high-mass star-forming regions which suggest that high-mass stars form in a similar way as their low-mass counterparts, i.e., via disk accretion. The results presented in this thesis provide constraints on the initial conditions and early stages of both low- and high-mass star formation. In particular, this thesis presents several observational results on the early stages of clustered star formation, which is the dominant mode of star formation in our Galaxy.

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The first observations of solar X-rays date back to late 1940 s. In order to observe solar X-rays the instruments have to be lifted above the Earth s atmosphere, since all high energy radiation from the space is almost totally attenuated by it. This is a good thing for all living creatures, but bad for X-ray astronomers. Detectors observing X-ray emission from space must be placed on-board satellites, which makes this particular discipline of astronomy technologically and operationally demanding, as well as very expensive. In this thesis, I have focused on detectors dedicated to observing solar X-rays in the energy range 1-20 keV. The purpose of these detectors was to measure solar X-rays simultaneously with another X-ray spectrometer measuring fluorescence X-ray emission from the Moon surface. The X-ray fluorescence emission is induced by the primary solar X-rays. If the elemental abundances on the Moon were to be determined with fluorescence analysis methods, the shape and intensity of the simultaneous solar X-ray spectrum must be known. The aim of this thesis is to describe the characterization and operation of our X-ray instruments on-board two Moon missions, SMART-1 and Chandrayaan-1. Also the independent solar science performance of these two almost similar X-ray spectrometers is described. These detectors have the following two features in common. Firstly, the primary detection element is made of a single crystal silicon diode. Secondly, the field of view is circular and very large. The data obtained from these detectors are spectra with a 16 second time resolution. Before launching an instrument into space, its performance must be characterized by ground calibrations. The basic operation of these detectors and their ground calibrations are described in detail. Two C-flares are analyzed as examples for introducing the spectral fitting process. The first flare analysis shows the fit of a single spectrum of the C1-flare obtained during the peak phase. The other analysis example shows how to derive the time evolution of fluxes, emission measures (EM) and temperatures through the whole single C4 flare with the time resolution of 16 s. The preparatory data analysis procedures are also introduced in detail. These are required in spectral fittings of the data. A new solar monitor design equipped with a concentrator optics and a moderate size of field of view is also introduced.