997 resultados para Medieval sources


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Methane is a potent greenhouse gas with a global warming potential ∼28 times that of carbon dioxide. Consequently, sources and sinks that influence the concentration of methane in the atmosphere are of great interest. In Australia, agriculture is the primary source of anthropogenic methane emissions (60.4% of national emissions, or 3260kt-1methaneyear-1, between 1990 and 2011), and cropping and grazing soils represent Australia's largest potential terrestrial methane sink. As of 2011, the expansion of agricultural soils, which are ∼70% less efficient at consuming methane than undisturbed soils, to 59% of Australia's land mass (456Mha) and increasing livestock densities in northern Australia suggest negative implications for national methane flux. Plant biomass burning does not appear to have long-term negative effects on methane flux unless soils are converted for agricultural purposes. Rice cultivation contributes marginally to national methane emissions and this fluctuates depending on water availability. Significant available research into biological, geochemical and agronomic factors has been pertinent for developing effective methane mitigation strategies. We discuss methane-flux feedback mechanisms in relation to climate change drivers such as temperature, atmospheric carbon dioxide and methane concentrations, precipitation and extreme weather events. Future research should focus on quantifying the role of Australian cropping and grazing soils as methane sinks in the national methane budget, linking biodiversity and activity of methane-cycling microbes to environmental factors, and quantifying how a combination of climate change drivers will affect total methane flux in these systems.

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The specific activity of glutamine synthetase (L-glutamate: ammonia ligase, EC 6.3.1.2) in surface grown Aspergillus niger was increased 3-5 fold when grown on L-glutamate or potassium nitrate, compared to the activity obtained on ammonium chloride. The levels of glutamine synthetase was regulated by the availability of nitrogen source like NH4 + , and further, the enzyme is repressed by increasing concentrations of NH4 +. In contrast to other micro-organisms, the Aspergillus niger enzyme was neither specifically inactivated by NH4+ or L-glutamine nor regulated by covalent modification.Glutamine synthetase from Aspergillus niger was purified to homogenity. The native enzyme is octameric with a molecular weight of 385,000±25,000. The enzyme also catalyses Mn2+ or Mg2+-dependent synthetase and Mn2+-dependent transferase activity.Aspergillus niger glutamine synthetase was completely inactivated by two mol of phenylglyoxal and one mol of N-ethylmaleimide with second order rate constants of 3·8 M–1 min–1 and 760 M–1 min–1 respectively. Ligands like Mg. ATP, Mg. ADP, Mg. AMP, L-glutamate NH4+, Mn2+ protected the enzyme against inactivation. The pattern of inactivation and protection afforded by different ligands against N-ethylamaleimide and phenylglyoxal was remarkably similar. These results suggest that metal ATP complex acts as a substrate and interacts with an arginine ressidue at the active site. Further, the metal ion and the free nucleotide probably interact at other sites on the enzyme affecting the catalytic activity.

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A central tenet in the theory of reliability modelling is the quantification of the probability of asset failure. In general, reliability depends on asset age and the maintenance policy applied. Usually, failure and maintenance times are the primary inputs to reliability models. However, for many organisations, different aspects of these data are often recorded in different databases (e.g. work order notifications, event logs, condition monitoring data, and process control data). These recorded data cannot be interpreted individually, since they typically do not have all the information necessary to ascertain failure and preventive maintenance times. This paper presents a methodology for the extraction of failure and preventive maintenance times using commonly-available, real-world data sources. A text-mining approach is employed to extract keywords indicative of the source of the maintenance event. Using these keywords, a Naïve Bayes classifier is then applied to attribute each machine stoppage to one of two classes: failure or preventive. The accuracy of the algorithm is assessed and the classified failure time data are then presented. The applicability of the methodology is demonstrated on a maintenance data set from an Australian electricity company.

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This paper investigates the short-run effects of economic growth on carbon dioxide emissions from the combustion of fossil fuels and the manufacture of cement for 189 countries over the period 1961-2010. Contrary to what has previously been reported, we conclude that there is no strong evidence that the emissions-income elasticity is larger during individual years of economic expansion as compared to recession. Significant evidence of asymmetry emerges when effects over longer periods are considered. We find that economic growth tends to increase emissions not only in the same year, but also in subsequent years. Delayed effects - especially noticeable in the road transport sector - mean that emissions tend to grow more quickly after booms and more slowly after recessions. Emissions are more sensitive to fluctuations in industrial value added than agricultural value added, with services being an intermediate case. On the expenditure side, growth in consumption and growth in investment have similar implications for national emissions. External shocks have a relatively large emissions impact, and the short-run emissions-income elasticity does not appear to decline as incomes increase. Economic growth and emissions have been more tightly linked in fossil-fuel rich countries.

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The improvement terms in the generalised energy-momentum tensor of Callan, Coleman and Jackiw can be derived from a variational principle if the Lagrangian is generalised to describe coupling between ‘matter’ fields and a spin-2 boson field. The required Lorentz-invariant theory is a linearised version of Kibble-Sciama theory with an additional (generally-covariant) coupling term in the Lagrangian. The improved energy-momentum tensor appears as the source of the spin-2 field, if terms of second order in the coupling constant are neglected.

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In the High Middle Ages female saints were customarily noble virgins. Thus, as a wife and a mother of eight children, the Swedish noble lady Birgitta (1302/3 1373) was an atypical candidate for sanctity. However, in 1391 she was canonized only 18 years after her death and became a role model for many late medieval women, who were mothers and widows. The dissertation Power and Authority Birgitta of Sweden and Her Revelations investigates how Birgitta went about establishing her power and authority during the first ten years of her career as a living saint, in 1340 1349. It is written from the perspectives of gender, authority, and power. The sources consist of approximately seven hundred revelations, hagiographical texts and other medieval documents. This work concentrates on the interaction between Birgitta and her audience. During her lifetime Birgitta was already regarded as a holy woman, as a living saint. A living saint could be given no formal papal or other recognition, for one could never be certain about his or her future activities. Thus, the living saint needed an audience for whom to perform signs of sanctity. In this study particular attention is paid to situations within which the power relations between the living saint and her audience can be traced and are open to critical analysis. Situations of conflict that arose in Birgitta s life are especially fruitful for this purpose. During the Middle Ages, institutional power and authority were exclusively in the hands of secular male leaders and churchmen. In this work it is argued, however, that Birgitta used different kinds of power than men. It is evident that she exercized influence on lay people as well as on secular and clerical authorities. The second, third, and fourth chapter of this study examine the beginning of Birgitta s career as a visionary, what factors and influences lay behind it, and what kind of roles they played in establishing her religious authority. The fifth, sixth, and seventh chapter concentrate on Birgitta s exercising of power in specific situations during her time in Sweden until she left on a pilgrimage to Rome in 1349. The central question is how she exercised power with different people. As a result, this book will offer a narrative of Birgitta s social interactions in Sweden seen from the perspectives of power and authority. Along with the concept of power, authority is a key issue. By definition, one who has power also has authority but a person who does not have official power can, nevertheless, have authority. Authority in action is defined here as meaning that a person was listened to. Birgitta acted both in situations of open conflict and where no conflict was evident. Her strategies included, for example, inducement, encouragement and flattery. In order to make people do as she felt was right she also threatened them openly with divine wrath. Sometimes she even used both positive persuasion and threats. Birgitta s power seems very similar to that of priests and ascetics. Common to all of them was that their power demanded interaction with other people and audiences. Because Birgitta did not have power and authority ex officio she had to persuade people to believe in her powers. She did this because she was convinced of her mission and sought to make people change their lives. In so doing, she moved from the domestic field to the public fields of religion and politics.

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This study focuses on the theory of individual rights that the German theologian Conrad Summenhart (1455-1502) explicated in his massive work Opus septipartitum de contractibus pro foro conscientiae et theologico. The central question to be studied is: How does Summenhart understand the concept of an individual right and its immediate implications? The basic premiss of this study is that in Opus septipartitum Summenhart composed a comprehensive theory of individual rights as a contribution to the on-going medieval discourse on rights. With this rationale, the first part of the study concentrates on earlier discussions on rights as the background for Summenhart s theory. Special attention is paid to language in which right was defined in terms of power . In the fourteenth century writers like Hervaeus Natalis and William Ockham maintained that right signifies power by which the right-holder can to use material things licitly. It will also be shown how the attempts to describe what is meant by the term right became more specified and cultivated. Gerson followed the implications that the term power had in natural philosophy and attributed rights to animals and other creatures. To secure right as a normative concept, Gerson utilized the ancient ius suum cuique-principle of justice and introduced a definition in which right was seen as derived from justice. The latter part of this study makes effort to reconstructing Summenhart s theory of individual rights in three sections. The first section clarifies Summenhart s discussion of the right of the individual or the concept of an individual right. Summenhart specified Gerson s description of right as power, taking further use of the language of natural philosophy. In this respect, Summenhart s theory managed to bring an end to a particular continuity of thought that was centered upon a view in which right was understood to signify power to licit action. Perhaps the most significant feature of Summenhart s discussion was the way he explicated the implication of liberty that was present in Gerson s language of rights. Summenhart assimilated libertas with the self-mastery or dominion that in the economic context of discussion took the form of (a moderate) self-ownership. Summenhart discussion also introduced two apparent extensions to Gerson s terminology. First, Summenhart classified right as relation, and second, he equated right with dominion. It is distinctive of Summenhart s view that he took action as the primary determinant of right: Everyone has as much rights or dominion in regard to a thing, as much actions it is licit for him to exercise in regard to the thing. The second section elaborates Summenhart s discussion of the species dominion, which delivered an answer to the question of what kind of rights exist, and clarified thereby the implications of the concept of an individual right. The central feature in Summenhart s discussion was his conscious effort to systematize Gerson s language by combining classifications of dominion into a coherent whole. In this respect, his treatement of the natural dominion is emblematic. Summenhart constructed the concept of natural dominion by making use of the concepts of foundation (founded on a natural gift) and law (according to the natural law). In defining natural dominion as dominion founded on a natural gift, Summenhart attributed natural dominion to animals and even to heavenly bodies. In discussing man s natural dominion, Summenhart pointed out that the natural dominion is not sufficiently identified by its foundation, but requires further specification, which Summenhart finds in the idea that natural dominion is appropriate to the subject according to the natural law. This characterization lead him to treat God s dominion as natural dominion. Partly, this was due to Summenhart s specific understanding of the natural law, which made reasonableness as the primary criterion for the natural dominion at the expense of any metaphysical considerations. The third section clarifies Summenhart s discussion of the property rights defined by the positive human law. By delivering an account on juridical property rights Summenhart connected his philosophical and theological theory on rights to the juridical language of his times, and demonstrated that his own language of rights was compatible with current juridical terminology. Summenhart prepared his discussion of property rights with an account of the justification for private property, which gave private property a direct and strong natural law-based justification. Summenhart s discussion of the four property rights usus, usufructus, proprietas, and possession aimed at delivering a detailed report of the usage of these concepts in juridical discourse. His discussion was characterized by extensive use of the juridical source texts, which was more direct and verbal the more his discussion became entangled with the details of juridical doctrine. At the same time he promoted his own language on rights, especially by applying the idea of right as relation. He also showed recognizable effort towards systematizing juridical language related to property rights.

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Sangen ialo Rucous. The prayer book of the Schwenckfeldiens as a source for Michael Agricola The significance of the prayer book published by the Finnish reformer Michael Agricola in the year of 1544 has not been comprehended enough among the prayer literature of the Reformation century. Especially in foreign research literature one of the era s most extensive and versatile prayer books has been practically disregarded. According to the prayer book, Agricola appears to be a traditionalist, who derives most of his source material from medieval and old church prayer books. The low number of the prayers from Evangelical prayer books is noteworthy. The study in hand examines Agricola s theology expressed in his translation work of the prayer book of the mystic spiritualistic Schwenckfeldien movement. The prayer book of the Schwenckdeldiens diverged from Lutheranism was called Bekantnus der sünden and it was composed around the year of 1526. Agricola is the only prayer book collector who has regarded it as necessary to add all the 45 prayers of the Schwenckfeldien prayer book and its introduction to his book. In the prayers containing the Schwenckfeldien communion theology and Christology Agricola has not changed the content of the text, apparently because he was not aware of the problems involved in the Schwenckfeldien theology. On a few occasions Agricola added points of view concerning the church, priesthood, preaching the Word and sacraments to his prayers, which the Schwenckfeldiens despised. From the ten additions four Agricola created himself, the rest he borrowed from Wolfgang Capito s prayer book. As a source Agricola used Capito s Latin prayer book together with the German text from Bekantnus. When looking at the studied material, Agricola does not turn out to be a creative translator. Even though he had a model for a less restricted translation in Wolfgang Capito s prayer book, he sticks to his habit of translating word by word. Because not even a good example has had a liberating effect on his translation principles, Agricola cannot be considered a theologically orientated writer. The translation of the Schwenckfeldien prayers Agricola starts with Capito s prayer book. Very soon he takes the Bekantnus alongside Capito s text and abandons the use of Capito s prayer book in the middle of the translation process. Comparing Agricola s translation with the two texts in different languages has made it possible to create the disposition theory described above. On the basis of the disposition theory it can be concluded that Agricola first worked out a precise plan for his prayer book. Then he translated prayers theme by theme using multiple sources at the same time. Later Agricola fixed the disposition, which does not seem to have a direct paragon. From the prayers of the Schwenckfeldien prayer book Agricola translated 26 texts using the Bekantnus as an only base, from Capito s prayer book he translated four texts and 17 texts he translated using the two basic texts simultaneously. In the previous studies, words and texts added by Agricola have been examined as one problem unit. In this study the additions have been placed into three different categories: additions consequential on tautological parataxis, specifying additions and additions significant to the content. Due to Agricola s meticulous translation techniques, there are so few additions. Agricola does not show his own creativity even in the additions significant to the content but uses there some complete sentences or word fragments from the other prayers he has translated. In the translations of the prayers there are some unique appearing words and the analysis of the translation work shed a new light on the background of their first literary appearance in Finnish. Agricola s linguistic abilities turned out to be great. In those prayers where Agricola uses both the German and Latin basic texts at the same time, the translation process is a very intensive twine made on the basis of the two sources.

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Relative abundance distributions of multiply-charged ionic species have been measured for the RF spark and vacuum vibrator are ion sources, for a number of elements. An attempt has been made to explain the observed charge state distribution on the basis of models for the arc and spark plasma. The difficulties in the way of explaining the observed charge state distributions, using the LTE model with Saha distribution as well as the corona model, are pointed out. The distribution can be explained by a diffusion-dominated plasma model with known or calculated values for ionization cross-sections, the single impact model being suitable for the RF spark and the multiple impact model for the vibrator arc.

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We study the energetics of the accretion-induced outflow and then plausible jet around black holes/compact objects using a newly developed disc-outflow coupled model. Inter-connecting dynamics of outflow and accretion essentially upholds the conservation laws. The energetics depend strongly on the viscosity parameter α and the cooling factor f which exhibit several interesting features. The bolometric luminosities of ultra-luminous X-ray binaries (e.g. SS433) and family of highly luminous AGNs and quasars can be reproduced by the model under the super-Eddington accretion flows. Under appropriate conditions, low-luminous AGNs (e.g. Sagittarius A*) also fit reasonably well with the luminosity corresponding to a sub-Eddington accretion flow with f→1.

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The origin of the extragalactic gamma-ray background (EGRB) is still an open question, even nearly forty years after its discovery. The emission could originate either from truly diffuse processes or from unresolved point sources. Although the majority of the 271 point sources detected by EGRET (Energetic Gamma Ray Experiment Telescope) are unidentified, of the identified sources, blazars are the dominant candidates. Therefore, unresolved blazars may be considered the main contributor to the EGRB, and many studies have been carried out to understand their distribution, evolution and contribution to the EGRB. Considering that gamma-ray emission comes mostly from jets of blazars and that the jet emission decreases rapidly with increasing jet to line-of-sight angle, it is not surprising that EGRET was not able to detect many large inclination angle active galactic nuclei (AGNs). Though Fermi could only detect a few large inclination angle AGNs during the first three months of its survey, it is expected to detect many such sources in the near future. Since non-blazar AGNs are expected to have higher density as compared to blazars, these could also contribute significantly to the EGRB. In this paper, we discuss contributions from unresolved discrete sources including normal galaxies, starburst galaxies, blazars and off-axis AGNs to the EGRB.

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We discuss two temperature accretion disk flows around rotating black holes. As we know that to explain observed hard X-rays the choice of Keplerian angular momentum profile is not unique, we consider the sub-Keplerian regime of the disk. Without any strict knowledge of the magnetic field structure, we assume the cooling mechanism is dominated by bremsstrahlung process. We show that in a range of Shakura-Sunyaev viscosity parameter 0.2 greater than or similar to alpha greater than or similar to 0.0005, flow behavior varies widely, particularly by means of the size of disk, efficiency of cooling and corresponding temperatures of ions and electrons. We also show that the disk around a rotating black hole is hotter compared to that around a Schwarzschild black hole, rendering a larger difference between ion and electron temperatures in the former case. With all the theoretical solutions in hand, finally we reproduce the observed luminosities (L) of two extreme cases-the under-fed AGNs and quasars (e.g. Sgr A') with L greater than or similar to 10(33) erg/s to ultra-luminous X-ray sources with L similar to 10(41) erg/s, at different combinations of mass accretion rate, ratio of specific heats, Shakura-Sunyaev viscosity parameter and Kerr parameter, and conclude that Sgr A' may be an intermediate spinning black hole.