Vaikutusalakirjastojen muodostaminen Serpent-ARES-laskentaketjussa

Tässä diplomityössä on esitetty työn yhteydessä toteutetun Serpent-ARES-laskentaketjun muodostamiseksi tarvittavat toimenpiteet. ARES-reaktorisydän-simulaattorissa tarvittavien homogenisoitujen ryhmävakiokirjastojen muodostaminen Serpentiä käyttäen tekee laskentaketjusta muiden käytössä olevien reaktorisydämen laskentaketjujen mahdollisista virhelähteistä riippumattoman. Monte Carlo-laskentamenetelmään perustuvaa reaktorifysiikan laskentaohjelmaa käyttämällä ryhmävakiokirjastot muodostetaan uudella menetelmällä ja näin saadaan viranomaiskäyttöön voimayhtiöiden käyttämistä menetelmistä riippumaton laskentaketju reaktorien turvallisuusmarginaalien laskentaan. Työn yhteydessä muodostetun laskentaketjun ja tehtyjen vaikutusalakirjastojen muodostamisrutiinien sekä parametrisovitteiden toimivuus on todettu laskemalla Olkiluoto 3 - reaktorin alkulatauksen säätösauvojen tehokkuuksia ja sammutusmarginaaleja eri olosuhteissa. Menetelmä on todettu toimivaksi parametrien pätevyysalueella ja saadut laskentatulokset ovat oikeaa suuruusluokkaa. Parametrimallin tarkkuutta ja pätevyysaluetta on syytä vielä kehittää, ennen kuin laskentaketjua voidaan käyttää varmentamaan muilla menetelmillä laskettujen tulosten oikeellisuutta.

Development of an HTR-10 model in the Serpent reactor physics code

The use of exact coordinates of pebbles and fuel particles of pebble bed reactor modelling becoming possible in Monte Carlo reactor physics calculations is an important development step. This allows exact modelling of pebble bed reactors with realistic pebble beds without the placing of pebbles in regular lattices. In this study the multiplication coefficient of the HTR-10 pebble bed reactor is calculated with the Serpent reactor physics code and, using this multiplication coefficient, the amount of pebbles required for the critical load of the reactor. The multiplication coefficient is calculated using pebble beds produced with the discrete element method and three different material libraries in order to compare the results. The received results are lower than those from measured at the experimental reactor and somewhat lower than those gained with other codes in earlier studies.

The Long Tail of the Rainbow Serpent: New Technologies and the Protection and Promotion of Traditional Cultural Expressions

New technologies, in particular those stemming from digitisation, allow amongst other things the production of perfect copies, instantaneous and ubiquitous distribution of and easy access to information with no real location restrictions. The effects of these technological advances have largely been perceived as negative for the protection of traditional cultural expressions (TCE), both because of the peculiarities of the digital networked environment and because of the lack of appropriate intellectual property protection models for TCE. The purpose of this article is, while accounting for the diversity and complexity of issues related to TCE, to reveal a more positive side of digital technologies. It shows the potential of these to be proactively applied and the further reaching possibilities for designing an efficient multi-level and multi-faceted toolbox for the protection and promotion of TCE in the digital ecology.

The GATA factor Serpent is required for the onset of the humoral immune response in Drosophila embryos

Innate immunity in Drosophila is characterized by the inducible expression of antimicrobial peptides. We have investigated the development and regulation of immune responsiveness in Drosophila embryos after infection. Immune competence, as monitored by the induction of Cecropin A1-lacZ constructs, was observed first in the embryonic yolk. This observation suggests that the yolk plays an important role in the humoral immune response of the developing embryo by synthesizing antimicrobial peptides. Around midembryogenesis, the response in the yolk was diminished. Simultaneously, Cecropin expression became inducible in a large number of cells in the epidermis, demonstrating that late-stage embryos can synthesize their own antibiotics in the epidermis. This production likely serves to provide the hatching larva with an active antimicrobial barrier and protection against systemic infections. Cecropin expression in the yolk required the presence of a GATA site in the promoter as well as the involvement of the GATA-binding transcription factor Serpent (dGATAb). In contrast, neither the GATA site nor Serpent were necessary for Cecropin expression in the epidermis. Thus, the inducible immune responses in the yolk and in the epidermis can be uncoupled and call for distinct sets of transcription factors. Our data suggest that Serpent is involved in the distinction between a systemic response in the yolk/fat body and a local immune response in epithelial cells. In addition, the present study shows that signal transduction pathways controlling innate and epithelial defense reactions can be dissected genetically in Drosophila embryos.

The worship of the serpent traced throughout the world, and its traditions referred to the events in Paradise : proving the temptation and fall of man by the instrumentality of a serpent tempter /

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