878 resultados para worlds ahead
Resumo:
Transport of 1-14C-IAA in successive stem segments of Cuscuta was strictly basipetal in growing and non growing regions of the vine with a flux velocity of 10-12 mm/h (intercept method). This transport showed a distinct peaked profile, increasing from a low value at 10 mm from the apex to a maximum between 50 and 90 mm before declining to a low value again around 160 mm at which elongation growth ceased. The IAA transport profile paralleled the in vivo growth rate profile, though the latter peaked ahead of transport. A better correlation was observed between the profile of growth responsiveness of the vine to exogenous IAA application and the profile of IAA transport. Growth responsiveness was determined as the differential in growth rate of stem segments in vitro in the absence and presence of growth optimal concentration of IAA (10 μm). Retention of exogenous IAA in the stem was maximal where transport decreased, and this coincided with the region of maximal conjugation of applied 1-14C-IAA to aspartic acid to form indoleacetylaspartate (IAAsp). In addition to aspartate, IAA was conjugated to a small extent to an unidentified compound. IAA destruction by decarboxylation was greatest where transport was low, particularly in the nongrowing region, where lignification occurred (i.e., beyond 180 mm). At concentrations up to 20 μM, a pulse of 1-14C-IAA chased by "cold" IAA moved as a peak (with a peak displacement velocity of 12-18 mm/h) in the "growth" region of the vine, but became diffusionlike where growth either fell off steeply or ceased. At a higher (50 μM) IAA concentration, though uptake was not saturated, transport in the growth region became diffusionlike, indicating saturation of the system. Reduced IAA flux in the region where growth responsiveness to IAA declined coincided with the region of increased IAA conjugation. However, it cannot be concluded whether increased IAA conjugation was the cause or effect of decreased IAA flux. Application of benzyladenine to the vines in vivo, a treatment that elicited haustoria formation by 72 h, resulted in the inhibition of both IAA transport and elongation growth rate in the subapical region. In vitro treatment of vine segments with BA similarly increased IAA retention and decreased IAA transport. IAA loss was suppressed, and conjugation to IAAsp was enhanced. © 1989 Springer-Verlag New York Inc.
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In this work a single edge notched plate (SEN(T)) subjected to a tensile stress pulse is analysed, using a 2D plane strain dynamic finite element procedure. The interaction of the notch with a pre-nucleated hole ahead of it is examined. The background material is modelled by the Gurson constitutive law and ductile failure by microvoid coalescence in the ligament connecting the notch and the hole is simulated. Both rate independent and rate dependent material behaviour is considered. The notch tip region is subjected to a range of loading rates j by varying the peak value and the rise time of the applied stress pulse. The results obtained from these simulations are compared with a three point bend (TPB) specimen subjected to impact loading analysed in an earlier work [3] The variation of J at fracture initiation, J(c), with average loading rate j is obtained from the finite element simulations. It is found that the functional relationship between J(c) and j is fairly independent of the specimen geometry and is only dependent on material behaviour.
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The most important French literary movement of the 1950s and 1960s, the nouveau roman, radically questioned the idea of the novel as storytelling, claiming that narratives create a false illusion of the world’s intelligibility. However, in the 1970s storytelling finds its way back into the French novel – a shift that has been characterized as the “return of the narrative”. In my article, I argue that the “narrative turn” in the French novel of the 1970s can be seen as a turn towards a fundamentally hermeneutic view of the narrative mediatedness of our relation to the world. From a hermeneutic perspective, the nouveaux romanciers – insofar as they reject the narrative in order to disclose the discontinuous, fragmentary and chaotic nature of reality – hang onto the positivistic idea that “real” is only that which is independent of human meaning-giving processes. By contrast, the hermeneutists, such as Paul Ricoeur, consider also the human experience of the world to be real, and largely narrative in form. This view is shared by the principal novelists associated with the narrative turn, such as Michel Tournier to whom man is a “mythological animal”. However, after the nouveau roman , narratives have lost their innocence: they no longer appear as “natural” but are conscious of their own narrativity, historicity, and the way they represent only one possible – inevitably ethically and politically charged – perspective into reality. By making storytelling thematic and by telling “counter-stories” that question prevailing models of sense-making, Tournier and other “new storytellers” strive to promote critical reflection on the stories on the basis of which we orient to the world and narrate our lives – both as individuals and as communities.
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The modern food system and sustainable development form a conceptual combination that suggests sustainability deficits in environmental impacts and nutritional status of western populations. This study explores actors orientations towards sustainability by probing into social dynamics for sustainability within primary production and public consumption. If actors within these two worlds were to express converging orientations for sustainability, the system dynamics of the market would enable more sustainable growth in terms of production dictated by consumption. The study is based on a constructivist research approach with qualitative text analyses. The findings were validated by internal and external food system actors and are suggested to represent current social dynamics within Finnish food system. The key findings included primary producers social skilfulness, which enabled networking with other actors in very different paths of life, learning in order to promote one s trade, and trusting reflectively in partners in order to expand business. These activities extended the supply chain in a spiral fashion by horizontal and vertical forward integration, until large retailers were met for negotiations on a more equal basis. This mode of chain level coordination, typically building around the core of social and partnership relations, was coined as a socially overlaid network, and seen as sustainable coordination mode for endogenous growth. The caterers exhibited more or less committed professional identity for sustainability within their reach. The facilitating approaches for professional identities dealt successfully with local and organic food in addition to domestic food, and also imported food. The co-operation with supply chains created innovative solutions and savings for the business parties to be shared. There were also more complicated identities as juggling, critical and delimited approaches for sustainability, with less productive efforts due to restrictions such as absence of organisational sustainability strategy, weak presence of local and organic suppliers, limited understanding about sustainability and no organisational resources for informed choices for sustainability. The convergence between producers and caterers existed to an extent allowing suggestion that increased clarity about sustainable consumption and production by actors could be constructed using advanced tools. The study looks for introduction of more profound environmental and socio-economic knowledge through participatory research with supply chain actors. Learning in the workplace about food system reality in terms of supply chain co-operation may prove to be a change engine that leads to advanced network operations and a more sustainable food system.
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Abstract The modern food system and sustainable development form a conceptual combination that suggests sustainability deficits in the ways we deal with food consumption and production - in terms of economic relations, environmental impacts and nutritional status of western population. This study explores actors’ orientations towards sustainability by taking into account actors’ embedded positions within structures of the food system, actors’ economic relations and views about sustainability as well as their possibilities for progressive activities. The study looks particularly at social dynamics for sustainability within primary production and public consumption. If actors within these two worlds were to express converging orientations for sustainability, the system dynamics of the market would enable more sustainable growth in terms of production dictated by consumption. The study is based on a constructivist research approach with qualitative text analyses. The data consisted of three text corpora, the ‘local food corpus’, the ‘catering corpus’ and the ‘mixed corpus’. The local food actors were interviewed about their economic exchange relations. The caterers’ interviews dealt with their professional identity for sustainability. Finally, the mixed corpus assembled a dialogue as a participatory research approach, which was applied in order to enable researcher and caterer learning about the use of organic milk in public catering. The data were analysed for theoretically conceptualised relations, expressing behavioural patterns in actors’ everyday work as interpreted by the researcher. The findings were corroborated by the internal and external communities of food system actors. The interpretations have some validity, although they only present abstractions of everyday life and its rich, even opaque, fabric of meanings and aims. The key findings included primary producers’ social skilfulness, which enabled networking with other actors in very different paths of life, learning in order to promote one’s trade, and trusting reflectively in partners in order to extend business. These activities expanded the supply chain in a spiral fashion by horizontal and vertical forward integration, until large retailers were met for negotiations on a more equal or ‘other regarding’ basis. This kind of chain level coordination, typically building around the core of social and partnership relations, was coined as a socially overlaid network. It supported market access of local farmers, rooted in their farms, who were able to draw on local capital and labour in promotion of competitive business; the growth was endogenous. These kinds of chains – one conventional and one organic – were different from the strategic chain, which was more profit based and while highly competitive, presented exogenous growth as it depended on imported capital and local employees. However, the strategic chain offered learning opportunities and support for the local economy. The caterers exhibited more or less committed professional identity for sustainability within their reach. The facilitating and balanced approaches for professional identities dealt successfully with local and organic food in addition to domestic food, and also imported food. The co-operation with supply chains created innovative solutions and savings for the business parties to be shared. The rule-abiding approach for sustainability only made choices among organic supply chains without extending into co-operation with actors. There were also more complicated and troubled identities as juggling, critical and delimited approaches for sustainability, with less productive efforts due to restrictions such as absence of organisational sustainability strategy, weak presence of local and organic suppliers, limited understanding about sustainability and no organisational resources to develop changes towards a sustainable food system. Learning in the workplace about food system reality in terms of supply chain co-operation may prove to be a change engine that leads to advanced network operations and a more sustainable food system. The convergence between primary producers and caterers existed to an extent allowing suggestion that increased clarity about sustainable consumption and production by actors could be approached using advanced tools. The study looks for introduction of more profound environmental and socio-economic knowledge through participatory research with supply chain actors in order to promote more sustainable food systems. Summary of original publications and the authors’ contribution I Mikkola, M. & Seppänen, L. 2006. Farmers’ new participation in food chains: making horizontal and vertical progress by networking. In: Langeveld, H. & Röling N. (Eds.). Changing European farming systems for a better future. New visions for rural areas. Wageningen, The Netherlands. Wageningen Academic Publishers: 267–271. II Mikkola, M. 2008. Coordinative structures and development of food supply chains. British Food Journal 110 (2): 189–205. III Mikkola, M. 2009. Shaping professional identity for sustainability. Evidence in Finnish public catering. Appetite 53 (1): 56–65. IV Mikkola, M. 2009. Catering for sustainability: building a dialogue on organic milk. Agronomy Research 7 (Special issue 2): 668–676. Minna Mikkola has been responsible for developing the generic research frame, particular research questions, the planning and collection of the data, their qualitative analysis and writing the articles I, II, III and IV. Dr Laura Seppänen has contributed to the development of the generic research frame and article I by introducing the author to the basic concepts of economic sociology and by supporting the writing of article II with her critical comments. Articles are printed with permission from the publishers.
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Vegetation maps and bioclimatic zone classifications communicate the vegetation of an area and are used to explain how the environment regulates the occurrence of plants on large scales. Many practises and methods for dividing the world’s vegetation into smaller entities have been presented. Climatic parameters, floristic characteristics, or edaphic features have been relied upon as decisive factors, and plant species have been used as indicators for vegetation types or zones. Systems depicting vegetation patterns that mainly reflect climatic variation are termed ‘bioclimatic’ vegetation maps. Based on these it has been judged logical to deduce that plants moved between corresponding bioclimatic areas should thrive in the target location, whereas plants moved from a different zone should languish. This principle is routinely applied in forestry and horticulture but actual tests of the validity of bioclimatic maps in this sense seem scanty. In this study I tested the Finnish bioclimatic vegetation zone system (BZS). Relying on the plant collection of Helsinki University Botanic Garden’s Kumpula collection, which according to the BZS is situated at the northern limit of the hemiboreal zone, I aimed to test how the plants’ survival depends on their provenance. My expectation was that plants from the hemiboreal or southern boreal zones should do best in Kumpula, whereas plants from more southern and more northern zones should show progressively lower survival probabilities. I estimated probability of survival using collection database information of plant accessions of known wild origin grown in Kumpula since the mid 1990s, and logistic regression models. The total number of accessions I included in the analyses was 494. Because of problems with some accessions I chose to separately analyse a subset of the complete data, which included 379 accessions. I also analysed different growth forms separately in order to identify differences in probability of survival due to different life strategies. In most analyses accessions of temperate and hemiarctic origin showed lower survival probability than those originating from any of the boreal subzones, which among them exhibited rather evenly high probabilities. Exceptionally mild and wet winters during the study period may have killed off hemiarctic plants. Some winters may have been too harsh for temperate accessions. Trees behaved differently: they showed an almost steadily increasing survival probability from temperate to northern boreal origins. Various factors that could not be controlled for may have affected the results, some of which were difficult to interpret. This was the case in particular with herbs, for which the reliability of the analysis suffered because of difficulties in managing their curatorial data. In all, the results gave some support to the BZS, and especially its hierarchical zonation. However, I question the validity of the formulation of the hypothesis I tested since it may not be entirely justified by the BZS, which was designed for intercontinental comparison of vegetation zones, but not specifically for transcontinental provenance trials. I conclude that botanic gardens should pay due attention to information management and curational practices to ensure the widest possible applicability of their plant collections.
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Merkittävä osa alkuperäislääkevalmistajien tutkimus- ja tuotekehityskuluista näyttää olevan suunnattu olemassa olevien lääkkeiden kehittämiseen. Tämä voi oletettavasti johtaa kiinnostaviin formulaatiokehitysstrategioihin. Tutkimuksen tarkoituksena oli selvittää, voidaanko farmaseuttisen tuotekehityksen trendejä havaita myönnettyjen myyntilupien perusteella. Tutkimuksen mielenkiinnon kohteena olivat myös suurimpien lääkeyritysten käyttämät elinkaaren hallinnan keinot, joilla suojataan myyvimpiä tuotteita geneeriseltä kilpailulta ja varmistetaan markkinaosuus. Tutkimuksen painopiste oli kiinteissä oraalisissa lääkevalmisteissa. Laadullisten ja määrällisten menetelmien yhdistelmää käytettiin laajan näkökulman saamiseksi tutkittavaan aiheeseen. Suomalaisten myyntilupaviranomaisten haastatteluja käytettiin keräämään taustatietoa tutkimuksen määrällistä osaa varten. Määrällinen osa koostui myyntilupatietokannoista, jotka käsittivät kaikkien menettelyjen kautta Suomessa myönnetyt myyntiluvat, keskitetyn menettelyn kautta EU:ssa myönnetyt myyntiluvat ja maailman kymmenen suurinta lääkeyritystä USA:ssa. Tutkimustulosten perusteella rinnakkaislääkkeiden määrässä tapahtui merkittävä nousu Suomessa kaikkien menettelyjen kautta myönnetyissä myyntiluvissa ja EU:ssa keskitetyn menettelyn kautta myönnetyissä myyntiluvissa vuosina 2000-2010. Tämä muutos saattaa ainakin osaksi johtua lainsäädännöllisistä muutoksista, joilla luotiin kannustimia rinnakkaislääkkeiden käyttöön ja valmistukseen, kuten lääkevaihto ja viitehintajärjestelmä. USA:n tiedot osoittivat suurten lääkevalmistajien kiinnostuksen elinkaaren hallintaan: suurin osa maailman kymmenelle suurimmalle lääkeyritykselle myönnetyistä myyntiluvista vuosina 2005-2010 oli tähän tarkoitukseen. Elinkaaren hallinnan suhde uusiin lääkeaineisiin oli lähes 4:1. Kiinteä oraalinen lääkemuoto on kiistatta kaikista suosituin tapa annostella lääke, minkä vahvistivat sekä arvioijien haastattelut että myyntilupatiedot. Kiinteiden oraalisten rooli oli entistäkin korostuneempi rinnakkaislääkkeiden kohdalla. Kun innovatiivisuutta mitattiin epätyypillisten annosmuotojen määrällä, USA:n tiedot kiinteistä oraalisista lääkemuodoista osoittivat vahvaa innovatiivisuutta Suomen ja EU:n tietoihin verrattuna. Tämä saattaa heijastaa suurten lääkeyritysten innovatiivista tuotevalikoimaa. Epätyypillisten kiinteiden oraalisten annosmuotojen osuus oli huomattavasti pienempi rinnakkaislääkkeissä kuin alkuperäislääkkeissä kaikilla alueilla. Elinkaaren hallinnassa käytetyimmät strategiat olivat uusi formulaatio, uusi vahvuus ja uusi yhdistelmä olemassa olevasta valmisteesta. Kiinteiden oraalisten lääkemuotojen osalta kaksi kolmasosaa uusista elinkaaren hallinnan formulaatioista oli säädellysti vapauttavia valmisteita. Elinkaaren hallinta on olennainen osa suurten lääkeyritysten liiketoimintastrategiaa, ja sen tärkeyttä havainnollistettiin Coreg-tablettien tapausesimerkillä.
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Embryonic stem cells offer potentially a ground-breaking insight into health and diseases and are said to offer hope in discovering cures for many ailments unimaginable few years ago. Human embryonic stem cells are undifferentiated, immature cells that possess an amazing ability to develop into almost any body cell such as heart muscle, bone, nerve and blood cells and possibly even organs in due course. This remarkable feature, enabling embryonic stem cells to proliferate indefinitely in vitro (in a test tube), has branded them as a so-called miracle cure . Their potential use in clinical applications provides hope to many sufferers of debilitating and fatal medical conditions. However, the emergence of stem cell research has resulted in intense debates about its promises and dangers. On the one hand, advocates hail its potential, ranging from alleviating and even curing fatal and debilitating diseases such as Parkinson s, diabetes, heart ailments and so forth. On the other hand, opponents decry its dangers, drawing attention to the inherent risks of human embryo destruction, cloning for research purposes and reproductive cloning eventually. Lately, however, the policy battles surrounding human embryonic stem cell innovation have shifted from being a controversial research to scuffles within intellectual property rights. In fact, the ability to obtain patents represents a pivotal factor in the economic success or failure of this new biotechnology. Although, stem cell patents tend to more or less satisfy the standard patentability requirements, they also raise serious ethical and moral questions about the meaning of the exclusions on ethical or moral grounds as found in European and to an extent American and Australian patent laws. At present there is a sort of a calamity over human embryonic stem cell patents in Europe and to an extent in Australia and the United States. This in turn has created a sense of urgency to engage all relevant parties in the discourse on how best to approach patenting of this new form of scientific innovation. In essence, this should become a highly favoured patenting priority. To the contrary, stem cell innovation and its reliance on patent protection risk turmoil, uncertainty, confusion and even a halt on not only stem cell research but also further emerging biotechnology research and development. The patent system is premised upon the fundamental principle of balance which ought to ensure that the temporary monopoly awarded to the inventor equals that of the social benefit provided by the disclosure of the invention. Ensuring and maintaining this balance within the patent system when patenting human embryonic stem cells is of crucial contemporary relevance. Yet, the patenting of human embryonic stem cells raises some fundamental moral, social and legal questions. Overall, the present approach of patenting human embryonic stem cell related inventions is unsatisfactory and ineffective. This draws attention to a specific question which provides for a conceptual framework for this work. That question is the following: how can the investigated patent offices successfully deal with patentability of human embryonic stem cells? This in turn points at the thorny issue of application of the morality clause in this field. In particular, the interpretation of the exclusions on ethical or moral grounds as found in Australian, American and European legislative and judicial precedents. The Thesis seeks to compare laws and legal practices surrounding patentability of human embryonic stem cells in Australia and the United States with that of Europe. By using Europe as the primary case study for lessons and guidance, the central goal of the Thesis then becomes the determination of the type of solutions available to Europe with prospects to apply such to Australia and the United States. The Dissertation purports to define the ethical implications that arise with patenting human embryonic stem cells and intends to offer resolutions to the key ethical dilemmas surrounding patentability of human embryonic stem cells and other morally controversial biotechnology inventions. In particular, the Thesis goal is to propose a functional framework that may be used as a benchmark for an informed discussion on the solution to resolving ethical and legal tensions that come with patentability of human embryonic stem cells in Australian, American and European patent worlds. Key research questions that arise from these objectives and which continuously thread throughout the monograph are: 1. How do common law countries such as Australia and the United States approach and deal with patentability of human embryonic stem cells in their jurisdictions? These practices are then compared to the situation in Europe as represented by the United Kingdom (first two chapters), the Court of Justice of the European Union and the European Patent Office decisions (Chapter 3 onwards) in order to obtain a full picture of the present patenting procedures on the European soil. 2. How are ethical and moral considerations taken into account at patent offices investigated when assessing patentability of human embryonic stem cell related inventions? In order to assess this part, the Thesis evaluates how ethical issues that arise with patent applications are dealt with by: a) Legislative history of the modern patent system from its inception in 15th Century England to present day patent laws. b) Australian, American and European patent offices presently and in the past, including other relevant legal precedents on the subject matter. c) Normative ethical theories. d) The notion of human dignity used as the lowest common denominator for the interpretation of the European morality clause. 3. Given the existence of the morality clause in form of Article 6(1) of the Directive 98/44/EC of the European Parliament and of the Council of 6 July 1998 on the legal protection of biotechnological inventions which corresponds to Article 53(a) European Patent Convention, a special emphasis is put on Europe as a guiding principle for Australia and the United States. Any room for improvement of the European morality clause and Europe s current manner of evaluating ethical tensions surrounding human embryonic stem cell inventions is examined. 4. A summary of options (as represented by Australia, the United States and Europe) available as a basis for the optimal examination procedure of human embryonic stem cell inventions is depicted, whereas the best of such alternatives is deduced in order to create a benchmark framework. This framework is then utilised on and promoted as a tool to assist Europe (as represented by the European Patent Office) in examining human embryonic stem cell patent applications. This method suggests a possibility of implementing an institution solution. 5. Ultimately, a question of whether such reformed European patent system can be used as a founding stone for a potential patent reform in Australia and the United States when examining human embryonic stem cells or other morally controversial inventions is surveyed. The author wishes to emphasise that the guiding thought while carrying out this work is to convey the significance of identifying, analysing and clarifying the ethical tensions surrounding patenting human embryonic stem cells and ultimately present a solution that adequately assesses patentability of human embryonic stem cell inventions and related biotechnologies. In answering the key questions above, the Thesis strives to contribute to the broader stem cell debate about how and to which extent ethical and social positions should be integrated into the patenting procedure in pluralistic and morally divided democracies of Europe and subsequently Australia and the United States.
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In this paper I will offer a novel understanding of a priori knowledge. My claim is that the sharp distinction that is usually made between a priori and a posteriori knowledge is groundless. It will be argued that a plausible understanding of a priori and a posteriori knowledge has to acknowledge that they are in a constant bootstrapping relationship. It is also crucial that we distinguish between a priori propositions that hold in the actual world and merely possible, non-actual a priori propositions, as we will see when considering cases like Euclidean geometry. Furthermore, contrary to what Kripke seems to suggest, a priori knowledge is intimately connected with metaphysical modality, indeed, grounded in it. The task of a priori reasoning, according to this account, is to delimit the space of metaphysically possible worlds in order for us to be able to determine what is actual.
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The dissertation discusses the conceptions of place and landscape amongst Nenets living on the island of Kolguyev or being of Kolguyev descent. The conceptions are examined through the everyday life of the community, oral recollections and narration that unfold meanings related to the island. The research material has been collected in ethnographic fieldwork in 2000 2005. The duration of individual fieldworks varies from two weeks to three months and their total duration is nearly six months. The fieldwork has been conducted both on the island and in the city of Nar yan-Mar. The main methods have been participant observation and recorded and unrecorded informal interviews. In addition to the field work data, archive materials, travel accounts, and other historical texts by outsiders about Kolguyev or the Nenets living in the European side of Russia have been used as a research material. The analysis is based on the idea of the place as a meeting point of the physical features, experiences in them and collective narration about them. The concept sense of place is used to describe the interaction of these three. Lived space manifests individual s or collective sense of place. The places form different kinds of networks of meanings which are called landscapes. Hot spots are places where different meanings accumulate. Furthermore, the material is analysed using the concepts of Tale World and Story Realm by Katherine Young. The Tale World is a realm created during the Story Realm, i.e. the event of narrations. The Tale Worlds are true as such but become evaluated in the Story Realm. The Tale Worlds are seen to arise both from the physical features of a place and from oral tradition, but at the same time these worlds give meanings to the place. The Tale Worlds are one of the central ingredients for the sense of place. One of the most central hot spots in Kolguyev is the arok harbour, where most of the themes of the pre-Soviet Tale Worlds are placed: trade and interaction with the Russians, rituals of the popular religion and arrival of the first Nenets to the island. arok is also part of the landscape of the coast where the meetings of Nenets and the other(s) are generally connected. Furthermore, arok is connected to the network of amans graves but also more generally to the landscape of collective sacred and sacrificial places. Another hot spot is the population centre of Bugrino which unfolds through the evaluations of the Tale Worlds. It also is the centre of the everyday life of the community studied. The Tale Worlds of the radiant past fastens on the population centre which is described through the negative models within the genre of litany. Sacred places, that represent the possibility to meet the Otherworld or mark places were encounters with the Otherworld have taken place, generate many kinds of landscapes in the island. They fasten on the graves of the amans, sirtya tradition, and to collective sacred places with their associations. The networks are not closed systems but are given meanings and new associations continuously in narration and recollection. They form multi-level and significant landscapes which reflect the fastening of the Kolguyev Nenets in the tundra of the island. In the research material the holy places and the popular religiousness are emphasised which is one of the most significant research results. It can be seen to reflect collective resistance and the questioning of the atheistic propaganda of the Soviet years. The narration and the recollection often refer also to the discourse of the anti-religious propaganda or use its strategies. The centrality of the holy places is also based on the tenacity of the religious Tale Worlds and sense of place and to the collective significance of the religion in general.
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The aim of this thesis was to study the crops currently used for biofuel production from the following aspects: 1. what should be the average yield/ ha to reach an energy balance at least 0 or positive 2. what are the shares of the primary and secondary energy flows in agriculture, transport, processing and usage, and 3. overall effects of biofuel crop cultivation, transport, processing and usage. This thesis concentrated on oilseed rape biodiesel and wheat bioethanol in the European Union, comparing them with competing biofuels, such as corn and sugarcane-based ethanol, and the second generation biofuels. The study was executed by comparing Life Cycle Assessment-studies from the EU-region and by analyzing them thoroughly from the differences viewpoint. The variables were the following: energy ratio, hectare yield (l/ha), impact on greenhouse gas emissions (particularly CO2), energy consumption in crop growing and processing one hectare of a particular crop to biofuel, distribution of energy in processing and effects of the secondary energy flows, like e.g. wheat straw. Processing was found to be the most energy consuming part in the production of biofuels. So if the raw materials will remain the same, the development will happen in processing. First generation biodiesel requires esterification, which consumes approximately one third of the process energy. Around 75% of the energy consumed in manufacturing the first generation wheat-based ethanol is spent in steam and electricity generation. No breakthroughs are in sight in the agricultural sector to achieve significantly higher energy ratios. It was found out that even in ideal conditions the energy ratio of first generation wheat-based ethanol will remain slightly under 2. For oilseed rape-based biodiesel the energy ratios are better, and energy consumption per hectare is lower compared to wheat-based ethanol. But both of these are lower compared to e.g. sugarcane-based ethanol. Also the hectare yield of wheat-based ethanol is significantly lower. Biofuels are in a key position when considering the future of the world’s transport sector. Uncertainties concerning biofuels are, however, several, like the schedule of large scale introduction to consumer markets, technologies used, raw materials and their availability and - maybe the biggest - the real production capacity in relation to the fuel consumption. First generation biofuels have not been the expected answer to environmental problems. Comparisons made show that sugarcane-based ethanol is the most prominent first generation biofuel at the moment, both from energy and environment point of view. Also palmoil-based biodiesel looks promising, although it involves environmental concerns as well. From this point of view the biofuels in this study - wheat-based ethanol and oilseed rape-based biodiesel - are not very competitive options. On the other hand, crops currently used for fuel production in different countries are selected based on several factors, not only based on thier relative general superiority. It is challenging to make long-term forecasts for the biofuel sector, but it can be said that satisfying the world's current and near future traffic fuel consumption with biofuels can only be regarded impossible. This does not mean that biofuels shoud be rejected and their positive aspects ignored, but maybe this reality helps us to put them in perspective. To achieve true environmental benefits through the usage of biofuels there must first be a significant drop both in traffic volumes and overall fuel consumption. Second generation biofuels are coming, but serious questions about their availability and production capacities remain open. Therefore nothing can be taken for granted in this issue, expect the need for development.
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It is proved that the infinitesimal look-ahead and look-back σ-fields of a random process disagree at atmost countably many time instants.
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Effect of constraint (stress triaxiality) on void growth near a notch tip in a FCC single crystal is investigated. Finite element simulations within the modified boundary layer framework are conducted using crystal plasticity constitutive equations and neglecting elastic anisotropy. Displacement boundary conditions based on model, elastic, two term K-T field are applied on the outer boundary of a large circular domain. A pre-nucleated void is considered ahead of a stationary notch tip. The interaction between the notch tip and the void is studied under different constraints (T-stress levels) and crystal orientations. It is found that negative T-stress retards the mechanisms of ductile fracture. However, the extent of retardation depends on the crystal orientation. Further, it is found that there exists a particular orientation which delays the ductile fracture processes and hence can potentially improve ductility. This optimal orientation depends on the constraint level. (C) 2010 Published by Elsevier B.V.
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We consider a wireless sensor network whose main function is to detect certain infrequent alarm events, and to forward alarm packets to a base station, using geographical forwarding. The nodes know their locations, and they sleep-wake cycle, waking up periodically but not synchronously. In this situation, when a node has a packet to forward to the sink, there is a trade-off between how long this node waits for a suitable neighbor to wake up and the progress the packet makes towards the sink once it is forwarded to this neighbor. Hence, in choosing a relay node, we consider the problem of minimizing average delay subject to a constraint on the average progress. By constraint relaxation, we formulate this next hop relay selection problem as a Markov decision process (MDP). The exact optimal solution (BF (Best Forward)) can be found, but is computationally intensive. Next, we consider a mathematically simplified model for which the optimal policy (SF (Simplified Forward)) turns out to be a simple one-step-look-ahead rule. Simulations show that SF is very close in performance to BF, even for reasonably small node density. We then study the end-to-end performance of SF in comparison with two extremal policies: Max Forward (MF) and First Forward (FF), and an end-to-end delay minimising policy proposed by Kim et al. 1]. We find that, with appropriate choice of one hop average progress constraint, SF can be tuned to provide a favorable trade-off between end-to-end packet delay and the number of hops in the forwarding path.
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In this paper, an overview of some recent computational studies by the authors on ductile crack initiation under mode I, dynamic loading is presented. In these studies, a large deformation finite element procedure is employed along with the viscoplastic version of the Gurson constitutive model that accounts for the micro-mechanical processes of void nucleation, growth and coalescence. A three-point bend fracture specimen subjected to impact, and a single edge notched specimen loaded by a tensile stress pulse are analysed. Several loading rates are simulated by varying the impact speed or the rise time and magnitude of the stress pulse. A simple model involving a semi-circular notch with a pre-nucleated circular hole situated ahead of it is considered. The growth of the hole and its interaction with the notch tip, which leads to plastic strain and porosity localization in the ligament connecting them, is simulated. The role of strain-rate dependence on ductile crack initiation at high loading rates, and the specimen geometry effect on the variation of dynamic fracture toughness with loading rate are Investigated.