977 resultados para Lava™ Ultimate


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Moisture absorption characteristics and its effects on the mechanical properties and failure process of polymers (neat epoxy and polyester resins) and composites with simple (glass, carbon and kevlar) and hybrid (glass-carbon, carbon-kevlar and kevlar-glass) fibres were experimentally determined before and after immersion in water at 343 K for 20 days. The maximum moisture content (Mm) and diffusion coefficient (Dx) of these composites were determined. The degradation in ultimate tensile strength and Young's modulus due to the moisture content were experimentally determined and found to be quite significant. Acoustic emissions, from specimens before and after exposure, were monitored during the load cycle, and revealed a significant change in the failure process of these composites. Scanning Electron Microscope (SEM) studies on failed exposed and unexposed specimens revealed resin leach out and fibre prominence.

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The aim of the dissertation is to explore the idea of philosophy as a path to happiness in classical Arabic philosophy. The starting point is in comparison of two distinct currents between the 10th and early 11th centuries, Peripatetic philosophy, represented by al-Fārābī and Ibn Sīnā, and Ismaili philosophy represented by al-Kirmānī and the Brethren of Purity. They initially offer two contrasting views about philosophy in that the attitude of the Peripatetics is rationalistic and secular in spirit, whereas for the Ismailis philosophy represents the esoteric truth behind revelation. Still, they converge in their view that the ultimate purpose of philosophy lies in its ability to lead man towards happiness. Moreover, they share a common concept of happiness as a contemplative ideal of human perfection, which refers primarily to an otherworldly state of the soul s ascent to the spiritual world. For both the way to happiness consists of two parts: theory and practice. The practical part manifests itself in the idea of the purification of the rational soul from its bodily attachments in order for it to direct its attention fully to the contemplative life. Hence, there appears an ideal of philosophical life with the goal of relative detachment from the worldly life. The regulations of the religious law in this context appear as the primary means for the soul s purification, but for all but al-Kirmānī they are complemented by auxiliary philosophical practices. The ascent to happiness, however, takes place primarily through the acquisition of theoretical knowledge. The saving knowledge consists primarily of the conception of the hierarchy of physical and metaphysical reality, but all of philosophy forms a curriculum through which the soul gradually ascends towards a spiritual state of being along an order that is inverse to the Neoplatonic emanationist hierarchy of creation. For Ismaili philosophy the ascent takes place from the exoteric religious sciences towards the esoteric philosophical knowledge. For Peripatetic philosophers logic performs the function of an instrument enabling the ascent, mathematics is treated either as propaedeutic to philosophy or as a mediator between physical and metaphysical knowledge, whereas physics and metaphysics provide the core of knowledge necessary for the attainment of happiness.

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Breast cancer is the most common cancer among women. Although its prognosis has improved nowadays, methods to predict the progression of the disease or to treat it are not comprehensive. This thesis work was initiated to elucidate in breast carcinogenesis the role of HuR, a ubiquitously expressed mRNA-binding protein that regulates gene expression posttranscriptionally. HuR is predominantly nuclear, but it shuttles between the nucleus and the cytoplasm, and this nucleocytoplasmic translocation is important for its function as a RNA-stabilizing and translational regulator. HuR has been associated with diverse cellular processes, for example carcinogenesis. The specific aims of my thesis work were to study the prognostic value of HuR in breast cancer and to clarify the mechanisms by which HuR contributes to breast carcinogenesis. My ultimate goal is, by better understanding the role of HuR in breast carcinogenesis, to aid in the discovery of novel targets for cancer therapies. HuR expression and localization was studied in paraffin-embedded preinvasive (atypical ductal hyperplasia, ADH, and ductal carcinoma in situ, DCIS) specimens as well in sporadic and familial breast cancer specimens. Our results show that cytoplasmic HuR expression was already elevated in ADH and remained elevated in DCIS as well as in cancer specimens. Clinicopathological analysis showed that cytoplasmic HuR expression associated with the more aggressive form of the disease in DCIS, and in cancer specimens it proved an independent marker for poor prognosis. Importantly, cytoplasmic HuR expression was significantly associated with poor outcome in the subgroups of small (2 cm) and axillary lymph node-negative breast cancers. HuR proved to be the first mRNA stability protein the expression of which is associated in breast cancer with poor outcome. To explore the mechanisms of HuR in breast carcinogenesis, lentiviral constructs were developed to inhibit and to overexpress the HuR expression in a breast epithelial cell line (184B5Me). Our results suggest that HuR mediates breast carcinogenesis by participating in processes important in cell transformation, in programmed cell death, and in cell invasion. Global gene expression analysis shows that HuR regulates genes participating in diverse cellular processes, and affects several pathways important in cancer development. In addition, we identified two novel target transcripts (connective tissue growth factor, CTGF, and Ras oncogene family member 31, RAB31) for HuR. In conclusion, because cytoplasmic HuR expression in breast cancer can predict the outcome of the disease it could serve in clinics as a prognostic marker. HuR accumulates in the cytoplasm even at its non-invasive stage (ADH and DCIS) of the carcinogenic process and supports functions essential in cell alteration. These data suggest that HuR contributes to carcinogenesis of the breast epithelium.

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This study in EU law analyses the reasoning of the Court of Justice (the Court of Justice of the European Union) in a set of its preliminary rulings. Preliminary rulings are answers to national courts questions on the interpretation (and validity) of EU law called preliminary references. These questions concern specific legal issues that have arisen in legal disputes before the national courts. The Court of Justice alone has the ultimate authority to interpret EU law. The preliminary rulings bind the national courts in the cases giving rise to the preliminary reference, and the interpretations of EU law offered in the preliminary rulings are considered generally binding on all instances applying EU law. EU law is often described as a dynamic legal order and the Court of Justice as at the vanguard of developing it. It is generally assumed that the Court of Justice is striving to realise the EU s meta-level purpose (telos): integration. Against this backdrop one can understand the criticism the Court of Justice is often faced with in certain fields of EU law that can be described as developing. This criticism concerns the Court s (negatively) activist way of not just stating the law but developing or even making law. It is difficult to analyse or prove wrong this accusation as it is not in methodological terms clearly established what constitutes judicial activism, or more exactly where the threshold of negative activism lies. Moreover, one popular approach to assessing the role of the Court of Justice described as integration through law has become fairly political, neglecting to take into consideration the special nature of law as both facilitating and constraining action, not merely a medium for furthering integration. This study offers a legal reasoning approach of a more legalist nature, in order to balance the existing mix of approaches to explaining what the Court of Justice does and how. Reliance on legal reasoning is found to offer a working framework for analysis, whereas the tools for an analysis based on activism are found lacking. The legal reasoning approach enables one to assess whether or not the Court of Justice is pertaining to its own established criteria of interpretation of EU law, and if it is not, one should look more in detail at how the interpretation fits with earlier case-law and doctrines of EU law. This study examines the reasoning of the Court of Justice in a set of objectively chosen cases. The emphasis of the study is on analysing how the Court of Justice applies the established criteria of interpretation it has assumed for itself. Moreover, the judgments are assessed not only in terms of reasoning but also for meaningful silences they contain. The analysis is furthermore contextualised by taking into consideration how the cases were commented by legal scholars, their substantive EU law context, and also their larger politico-historical context. In this study, the analysis largely shows that the Court of Justice is interpreting EU law in accordance with its previous practice. Its reasoning retains connection with the linguistic or semiotic criteria of interpretation, while emphasis lies on systemic reasoning. Moreover, although there are a few judgments where the Court of Justice offers clearly dynamic reasoning or what can be considered as substantive reasoning stemming from, for example, common sense or reasonableness, such reasons are most often given in addition to systemic ones. In this sense and even when considered in its broader context, the case-law analysed in this study does not portray a specifically activist image of the Court of Justice. The legal reasoning approach is a valid alternative for explaining how and why the Court of Justice interprets EU law as it does.

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OBJECTIVES. Oral foreign language skills are an integral part of one's social, academic and professional competence. This can be problematic for those suffering from foreign language communication apprehension (CA), or a fear of speaking a foreign language. CA manifests itself, for example, through feelings of anxiety and tension, physical arousal and avoidance of foreign language communication situations. According to scholars, foreign language CA may impede the language learning process significantly and have detrimental effects on one's language learning, academic achievement and career prospects. Drawing on upper secondary students' subjective experiences of communication situations in English as a foreign language, this study seeks, first, to describe, analyze and interpret why upper secondary students experience English language communication apprehension in English as a foreign language (EFL) classes. Second, this study seeks to analyse what the most anxiety-arousing oral production tasks in EFL classes are, and which features of different oral production tasks arouse English language communication apprehension and why. The ultimate objectives of the present study are to raise teachers' awareness of foreign language CA and its features, manifestations and impacts in foreign language classes as well as to suggest possible ways to minimize the anxiety-arousing features in foreign language classes. METHODS. The data was collected in two phases by means of six-part Likert-type questionnaires and theme interviews, and analysed using both quantitative and qualitative methods. The questionnaire data was collected in spring 2008. The respondents were 122 first-year upper secondary students, 68 % of whom were girls and 31 % of whom were boys. The data was analysed by statistical methods using SPSS software. The theme interviews were conducted in spring 2009. The interviewees were 11 second-year upper secondary students aged 17 to 19, who were chosen by purposeful selection on the basis of their English language CA level measured in the questionnaires. Six interviewees were classified as high apprehensives and five as low apprehensives according to their score in the foreign language CA scale in the questionnaires. The interview data was coded and thematized using the technique of content analysis. The analysis and interpretation of the data drew on a comparison of the self-reports of the highly apprehensive and low apprehensive upper secondary students. RESULTS. The causes of English language CA in EFL classes as reported by the students were both internal and external in nature. The most notable causes were a low self-assessed English proficiency, a concern over errors, a concern over evaluation, and a concern over the impression made on others. Other causes related to a high English language CA were a lack of authentic oral practise in EFL classes, discouraging teachers and negative experiences of learning English, unrealistic internal demands for oral English performance, high external demands and expectations for oral English performance, the conversation partner's higher English proficiency, and the audience's large size and unfamiliarity. The most anxiety-arousing oral production tasks in EFL classes were presentations or speeches with or without notes in front of the class, acting in front of the class, pair debates with the class as audience, expressing thoughts and ideas to the class, presentations or speeches without notes while seated, group debates with the class as audience, and answering to the teacher's questions involuntarily. The main features affecting the anxiety-arousing potential of an oral production task were a high degree of attention, a large audience, a high degree of evaluation, little time for preparation, little linguistic support, and a long duration.

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Accelerated ageing studies for three composite propellant formulations, namely polystyrene (PS)/ ammonium perchlorate (AP), polymethylmethacrylate (PMMA)/AP and poly phenol formaldehyde (PPF)/AP have been carried out in the temperature range of 55-125°C. Measurements of the ultimate compression strength (Uc) and isothermal decomposition rate (TD rate) were monitored as a function of storage time and temperature. The change in Uc was found to be linearly dependent on the change in TD rate irrespective of the propellant systems. Analysis of the results further revealed that the cause of ageing for both Uc and burning rate (r) is the thermal decomposition of the propellant. The safe-life for the change in mechanical properties was found to be higher compared to the change in r for PS and PMMA based propellants.

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Experimental studies (Bishop 1966) show that for saturated normally consolidated clay the cohesion varies linearly with depth. The ultimate bearing capacity in such soil is generally obtained by limit equilibrium and limit analysis methods. Sokolovski's (1960) approach to the method of characteristics is used to find the ultimate bearing capacity of saturated clay whose cohesion is homogeneous and isotropic. In this technical note, the method of characteristics is further developed to determine ultimate bearing capacity of clay whose cohesion varies linearly with depth.

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Attempts were made to produce directionally solidified, specifically grain aligned Al-6 wt pct Ni eutectic alloy using a laboratory scale ESR unit. For this purpose sand cast alloy electrodes were electroslag remelted under different mold conditions. The grain structure of the ingots obtained from these meltings showed that insulated silica molds gave the best vertical alignment of grains along the length of the ingot. The NiAl3 fibers within the grains tended to fan out and there was only a preferred alignment of fibers along the growth direction under the conditions of our experiments. The ESR parameters most suitable for vertical alignment of eutectic grains have been identified. In some electroslag remelting trials ingots were grown on a seed ingot. This resulted in a fewer vertical grains compared to the case when no seed ingot was used. The sand cast specimen of the eutectic exhibited a maximum tensile strength of around 88.2 MN/m2 (9.0 kg/mm2) whereas conventional ESR using water cooled mold gave strength value of 98.0 MN/m2 (10 kg/mm2). The directionally solidified ESR material showed longitudinal tensile strength as high as 213.7 MN/m2 (21.8 kg/mm2) which could be further increased to 220.6 MN/m2 (22.5 kg/mm2) by using the seed ingot. The average growth rate was varied between 5 to 25 mm/min during electroslag remelting in this study. The flow stresses, tangent modulus and ultimate tensile strength of directionally solidified eutectic increased with increasing growth rates.

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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 machine replication of human reading has been the subject of intensive research for more than three decades. A large number of research papers and reports have already been published on this topic. Many commercial establishments have manufactured recognizers of varying capabilities. Handheld, desk-top, medium-size and large systems costing as high as half a million dollars are available, and are in use for various applications. However, the ultimate goal of developing a reading machine having the same reading capabilities of humans still remains unachieved. So, there still is a great gap between human reading and machine reading capabilities, and a great amount of further effort is required to narrow-down this gap, if not bridge it. This review is organized into six major sections covering a general overview (an introduction), applications of character recognition techniques, methodologies in character recognition, research work in character recognition, some practical OCRs and the conclusions.

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In a number of applications of computerized tomography, the ultimate goal is to detect and characterize objects within a cross section. Detection of edges of different contrast regions yields the required information. The problem of detecting edges from projection data is addressed. It is shown that the class of linear edge detection operators used on images can be used for detection of edges directly from projection data. This not only reduces the computational burden but also avoids the difficulties of postprocessing a reconstructed image. This is accomplished by a convolution backprojection operation. For example, with the Marr-Hildreth edge detection operator, the filtering function that is to be used on the projection data is the Radon transform of the Laplacian of the 2-D Gaussian function which is combined with the reconstruction filter. Simulation results showing the efficacy of the proposed method and a comparison with edges detected from the reconstructed image are presented

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Diglycidyl ether–bisphenol-A-based epoxies toughened with various levels (0–12%) of chemically reacted liquid rubber, hydroxyl-terminated poly(butadiene-co-acrylonitrile) (HTBN) were studied for some of the mechanical and thermal properties. Although the ultimate tensile strength showed a continuous decrease with increasing rubber content, the toughness as measured by the area under the stress-vs.-strain curve and flexural strength reach a maximum around an optimum rubber concentration of 3% before decreasing. Tensile modulus was found to increase for concentrations below 6%. The glass transition temperature Tg as measured by DTA showed no variation for the toughened formulations. The TGA showed no variations in the pattern of decomposition. The weight losses for the toughened epoxies at elevated temperatures compare well with that of the neat epoxy. Scanning electron microscopy revealed the presence of a dual phase morphology with the spherical rubber particles precipitating out in the cured resin with diameter varying between 0.33 and 6.3 μm. In contrast, a physically blended rubber–epoxy showed much less effect towards toughening with the precipitated rubber particles of much bigger diameter (0.6–21.3 μm).

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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.

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Strength and behaviour of cement stabilised rammed earth (CSRE) is a scantily explored area. The present study is focused on the strength and elastic properties of CSRE. Characteristics of CSRE are influenced by soil composition, density of rammed earth, cement and moisture content. The study is focused on examining (a) role of clay content of the soil on strength of CSRE and arriving at optimum clay fraction of the soil mix, (b) influence of moisture content, cement content and density on strength and (c) stress-strain relationships and elastic properties for CSRE. Major conclusions are (a) there is considerable difference between dry and wet compressive strength of CSRE and the wet to dry strength ratio depends upon the clay fraction of soil mix and cement content, (b) optimum clay fraction yielding maximum compressive strength for CSRE is about 16%, (c) strength of CSRE is highly sensitive to density and for a 20% increase in density the strength increases by 300-500% and (d) in dry state the ultimate strain at failure for CSRE is as high as 1.5%, which is unusual for brittle materials.