33 resultados para Ultimate bearingcapacity


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This dissertation investigates the atomic power solution in Finland between 1955 - 1970. During these years a national arrangement for atomic energy technology evolved. The foundations of the Finnish atomic energy policy; the creation of basic legislation and the first governmental bodies, were laid between 1955 - 1965. In the late 1960's, the necessary technological and political decisions were made in order to purchase the first commercial nuclear reactor. A historical narration of this process is seen in the international context of "atoms for peace" policies and Cold War history in general. The geopolitical position of Finland made it necessary to become involved in the balanced participation in international scientific-technical exchange and assistive nuclear programs. The Paris Peace Treaty of 1947 categorically denied Finland acquisition of nuclear weapons. Accordingly, from the "Geneva year" of 1955, the emphasis was placed on peaceful purposes for atomic energy as well as on the education of national professionals in Finland. An initiative for the governmental atomic energy commission came from academia but the ultimate motive behind it was an anticipated structural change in the supply of national energy. Economically exploitable hydro power resources were expected to be built within ten years and atomic power was seen as a promising and complementing new energy technology. While importing fuels like coal was out of the question, because of scarce foreign currency, domestic uranium mineral deposits were considered as a potential source of nuclear fuel. Nevertheless, even then nuclear energy was regarded as just one of the possible future energy options. In the mid-1960 s a bandwagon effect of light water reactor orders was witnessed in the United States and soon elsewhere in the world. In Finland, two separate invitations for bids for nuclear reactors were initiated. This study explores at length both their preceding grounds and later phases. An explanation is given that the parallel, independent and nearly identical tenders reflected a post-war ideological rivalry between the state-owned utility Imatran Voima and private energy utilities. A private sector nuclear power association Voimayhdistys Ydin represented energy intensive paper and pulp industries and wanted to have free choice instead of being associated themselves with "the state monopoly" in energy pricing. As a background to this, a decisive change had started to happen within Finnish energy policy: private and municipal big thermal power plants became incorporated into the national hydro power production system. A characteristic phenomenon in the later history is the Soviet Union s effort to bid for the tender of Imatran Voima. A nuclear superpower was willing to take part in competition but not on a turnkey basis as Imatran Voima had presumed. As a result of many political turns and four years of negotiations the first Finnish commercial light water reactor was ordered from the East. Soon after this the private nuclear power group ordered its reactors from Sweden. This work interprets this as a reasonable geopolitical balance in choosing politically sensitive technology. Conceptually, social and political dimensions of new technology are emphasised. Negotiations on the Finnish atomic energy program are viewed as a cooperation and a struggle, where state-oriented and private-oriented regimes pose their own macro level views and goals (technopolitical imaginaries) and defend and advance their plans and practical modes of action (schemata). Here, not only technologists but even political actors are seen to contribute to technopolitical realisations.

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The purpose of this research project was to understand the steps of the retrotransposon BARE (BArley REtrotransposon) life cycle, from regulation of transcription to Virus-Like Particle (VLP) formation and ultimate integration back into the genome. Our study concentrates mainly on BARE1 transcriptional regulation because transcription is the crucial first step in the retrotransposon life cycle. The BARE element is a Class I LTR (Long Terminal Repeat) retrotransposon belonging to the Copia superfamily and was originally isolated in our research group. The LTR retrotransposons are transcribed from promoters in the LTRs and encode proteins for packaging of their transcripts, the reverse transcription of the transcripts into cDNA, and integration of the cDNA back into the genome. BARE1 is translated as a single polyprotein and cleaved into the capsid protein (GAG), integrase (IN), and reverse transcriptase-RNaseH (RT-RH) by the integral aspartic proteinase (AP). The BARE retrotransposon family comprises more than 104 copies in the barley (Hordeum vulgare) genome. The element is bound by long terminal repeats (LTRs, 1829 bp) containing promoters required for replication, signals for RNA processing, and motifs necessary for the integration of the cDNA. Members of the BARE1 subfamily are transcribed, translated, and form virus-like particles. Several basic questions concerning transcription are explored in the thesis: BARE1 transcription control, promoter choice in different barley tissues, start and termination sites for BARE transcripts, and BARE1 transcript polyadenylation (I). Polyadenylation is an important step during mRNA maturation, and determines its stability and translatability among other characteristics. Our work has found a novel way used by BARE1 to make extra GAG protein, which is critical for VLP formation. The discovery that BARE1 uses one RNA population for protein synthesis and another RNA population for making cDNA has established the most important step of the BARE1 life cycle (III). The relationship between BARE1 and BARE2 has been investigated. Besides BARE, we have examined the retrotransposon Cassandra (II), which uses a very different transcriptional mechanism and a fully parasitic life cycle. In general, this work is focused on BARE1 promoter activity, transcriptional regulation including differential promoter usage and RNA pools, extra GAG protein production and VLP formation. The results of this study give new insights into transcription regulation of LTR retrotransposons.

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The study attempts a reception-historical analysis of the Maccabean martyrs. The concept of reception has fundamentally to do with the re-use and interpretation of a text within new texts. In a religious tradition, certain elements become re-circulated and thus their reception may reflect the development of that particular tradition. The Maccabean martyrs first appear in 2 Maccabees. In my study, it is the Maccabean martyr figures who count as the received text; the focus is shifted from the interrelations between texts onto how the figures have been exploited in early Christian and Rabbinic sources. I have divided my sources into two categories and my analysis is in two parts. First, I analyze the reception of the Maccabean martyrs within Jewish and Christian historiographical sources, focusing on the role given to them in the depictions of the Maccabean Revolt (Chapter 3). I conclude that, within Jewish historiography, the martyrs are given roles, which vary between ultimate efficacy and marginal position with regard to making a historical difference. In Christian historiographical sources, the martyrs role grows in importance by time: however, it is not before a Christian cult of the Maccabean martyrs has been established, that the Christian historiographies consider them historically effective. After the first part, I move on to analyze the reception in sources, which make use of the Maccabean martyrs as paradigmatic figures (Chapter 4). I have suggested that the martyrs are paradigmatic in the context of martyrdom, persecution and destruction, on one hand, and in a homiletic context, inspiring religious celebration, on the other. I conclude that, as the figures are considered pre-Christian and biblical martyrs, they function well in terms of Christian martyrdom and have contributed to the development of its ideals. Furthermore, the presentation of the martyr figures in Rabbinic sources demonstrates how the notion of Jewish martyrdom arises from experiences of destruction and despair, not so much from heroic confession of faith in the face of persecution. Before the emergence of a Christian cult of the Maccabean martyrs, their identity is derived namely from their biblical position. Later on, in the homiletic context, their Jewish identity is debated and sometimes reconstructed as fundamentally Christian , despite of their Jewish origins. Similar debate about their identity is not found in the Rabbinic versions of their martyrdom and nothing there indicates a mutual debate between early Christians and Jews. A thematic comparison shows that the Rabbinic and Christian cases of reception are non-reliant on each other but also that they link to one another. Especially the scriptural connections, often made to the Maccabean mother, reveal the similarities. The results of the analyses confirm that the early history of Christianity and Rabbinic Judaism share, at least partly, the same religious environment and intertwining traditions, not only during the first century or two but until Late Antiquity and beyond. More likely, the reception of the Maccabean martyrs demonstrates that these religious traditions never ceased to influence one another.