973 resultados para Möbius Transformations


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Iron is one of the most common elements in the earth’s crust and thus its availability and economic viability far exceed that of metals commonly used in catalysis. Also the toxicity of iron is miniscule, compared to the likes of platinum and nickel, making it very desirable as a catalyst. Despite this, prior to the 21st century, the applicability of iron in catalysis was not thoroughly investigated, as it was considered to be inefficient and unselective in desired transformations. In this doctoral thesis, the application of iron catalysis in combination with organosilicon reagents for transformations of carbonyl compounds has been investigated together with insights into iron catalyzed chlorination of silanes and silanols. In the first part of the thesis, the synthetic application of iron(III)-catalyzed chlorination of silanes (Si-H) and the monochlorination of silanes (SiH2) using acetyl chloride as the chlorine source is described. The reactions proceed under ambient conditions, although some compounds need to be protected from excess moisture. In addition, the mechanism and kinetics of the chlorination reaction are briefly adressed. In the second part of this thesis a versatile methodology for transformation of carbonyl compounds into three different compound classes by changing the conditions and amounts of reagents is discussed. One pot reductive benzylation, reductive halogenation and reductive etherification of ketones and aldehydes using silanes as the reducing agent, halide source or cocatalyst, were investigated. Also the reaction kinetics and mechanism of the reductive halogenation of acetophenone are briefly discussed.

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The need for industries to remain competitive in the welding business, has created necessity to develop innovative processes that can exceed customer’s demand. Significant development in improving weld efficiency, during the past decades, still have their drawbacks, specifically in the weld strength properties. The recent innovative technologies have created smallest possible solid material known as nanomaterial and their introduction in welding production has improved the weld strength properties and to overcome unstable microstructures in the weld. This study utilizes a qualitative research method, to elaborate the methods of introducing nanomaterial to the weldments and the characteristic of the welds produced by different welding processes. The study mainly focuses on changes in the microstructural formation and strength properties on the welded joint and also discusses those factors influencing such improvements, due to the addition of nanomaterials. The effect of nanomaterial addition in welding process modifies the physics of joining region, thereby, resulting in significant improvement in the strength properties, with stable microstructure in the weld. The addition of nanomaterials in the welding processes are, through coating on base metal, addition in filler metal and utilizing nanostructured base metal. However, due to its insignificant size, the addition of nanomaterials directly to the weld, would poses complications. The factors having major influence on the joint integrity are dispersion of nanomaterials, characteristics of the nanomaterials, quantity of nanomaterials and selection of nanomaterials. The addition of nanomaterials does not affect the fundamental properties and characteristics of base metals and the filler metal. However, in some cases, the addition of nanomaterials lead to the deterioration of the joint properties by unstable microstructural formations. Still research are ongoing to achieve high joint integrity, in various materials through different welding processes and also on other factors that influence the joint strength.

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There is no index or criterion of aortic barodenervation, nor can we differentiate among rats that have suffered chronic sham, aortic or sino-aortic denervation. The objective of this study was to develop a procedure to generate at least one quantitative, reproducible and validated index that precisely evaluates the extent of chronic arterial barodenervation performed in conscious rats. Data from 79 conscious male Wistar rats of about 65-70 days of age with diverse extents of chronic arterial barodenervation and used in previous experiments were reanalyzed. The mean arterial pressure (MAP) and the heart rate (HR) of all rats were measured systematically before (over 1 h) and after three consecutive iv bolus injections of phenylephrine (PHE) and sodium nitroprusside (SNP). Four expressions of the effectiveness of barodenervation (MAP lability, PHE ratio, SNP ratio, and SNP-PHE slope) were assessed with linear fixed models, three-level average variance, average separation among levels, outlier box plot analysis, and overlapping graphic analysis. The analysis indicated that a) neither MAP lability nor SNP-PHE slope was affected by the level of chronic sodium intake; b) even though the Box-Cox transformations of both MAP lability [transformed lability index (TLI)] and SNP-PHE slope [transformed general sensitivity index (TGSI), {((3-(ΔHRSNP-ΔHRPHE/ΔMAPSNP-ΔMAPPHE))-0.4-1)/-0.04597}] could be two promising indexes, TGSI proved to be the best index; c) TLI and TGSI were not freely interchangeable indexes for this purpose. TGSI ranges that permit differentiation between sham (10.09 to 11.46), aortic (8.40 to 9.94) and sino-aortic (7.68 to 8.24) barodenervated conscious rats were defined.

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Cocoa flavour is greatly influenced by polyphenols. These compounds undergo a series of transformations during cocoa processing leading to the characteristic cocoa flavour. The use of exogenous polyphenol oxidase (PPO) proved to be useful to reduce polyphenol content in cocoa nibs. The effect of a PPO associated or not with air over total phenol and tannin content was evaluated. Cocoa nibs were autoclaved and treated with a PPO or water in the absence or presence of an air flow for 0.5, 1, 2 and 3 hours. Total phenol content was reduced in PPO or water treatments, but when associated with air there was an increase in phenol content. Tannin content was reduced only by the treatment with water and air.

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Technological innovations and the advent of digitalization have led retail business into one of its biggest transformations of all time. Consumer behaviour has changed rapidly and the customers are ever more powerful, demanding, tech-savvy and moving on various plat-forms. These attributes will continue to drive the development and robustly restructure the architecture of value creation in the retail business. The largest retail category, grocery yet awaits for a real disruption, but the signals for major change are already on the horizon. The first wave of online grocery retail was introduced in the mid 1990’s and it throve until millennium. Many overreactions, heavy investments and the burst IT-bubble almost stag-nated the whole industry for a long period of time. The second wave started with a venge-ance around 2010. Some research was carried out during the first wave from a single-viewpoint of online grocery retail, but without a comprehensive approach to online-offline business model integration. Now the accelerating growth of e-business has initiated an increased interest to examine the transformation from traditional business models towards e-business models and their integration on the companies’ traditional business models. This research strove to examine how can we recognize and analyze how digitalization and online channels are affecting the business models of grocery retail, by using business mod-el canvas as an analysis tool. Furthermore business model innovation and omnichannel retail were presented and suggested as potential solutions for these changes. 21 experts in online grocery industry were being interviewed. The thoughts of the informants were being qualitatively analysed by using an analysis tool called the business model canvas. The aim of this research was to portray a holistic view on the Omnichannel grocery retail business model, and the value chain, in which the case company Arina along with its partners are operating. The key conclusions exhibited that online grocery retail business model is not an alterna-tive model nor a substitute for the traditional grocery retail business model, though all of the business model elements are to some extent affected by it, but rather a complementary business model that should be integrated into the prevailing, conventional grocery retail business model. A set of business model elements, such as value proposition and distribu-tion channels were recognized as the most important ones and sources of innovation within these components were being illustrated. Segments for online grocery retail were empiri-cally established as polarized niche markets in contrast of the segmented mass-market of the conventional grocery retail. Business model innovation was proven to be a considera-ble method and a conceptual framework, by which to come across with new value proposi-tions that create competitive advantage for the company in the contemporary, changing business environment. Arina as a retailer can be considered as a industry model innovator, since it has initiated an entire industry in its market area, where other players have later on embarked on, and in which the contributors of the value chain, such as Posti depend on it to a great extent. Consumer behaviour clearly affects and appears everywhere in the digi-talized grocery trade and it drives customers to multiple platforms where retailers need to be present. Omnichannel retail business model was suggested to be the solution, in which the new technologies are being utilized, contemporary consumer behaviour is embedded in decision-making and all of the segments and their value propositions are being served seamlessly across the channels.

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This thesis is done as a part of the NEOCARBON project. The aim of NEOCARBON project is to study a fully renewable energy system utilizing Power-to-Gas or Power-to-Liquid technology for energy storage. Power-to-Gas consists of two main operations: Hydrogen production via electrolysis and methane production via methanation. Methanation requires carbon dioxide and hydrogen as a raw material. This thesis studies the potential carbon dioxide sources within Finland. The different sources are ranked using the cost and energy penalty of the carbon capture, carbon biogenity and compatibility with Power-to-Gas. It can be concluded that in Finland there exists enough CO2 point sources to provide national PtG system with sufficient amounts of carbon. Pulp and paper industry is single largest producer of biogenic CO2 in Finland. It is possible to obtain single unit capable of grid balancing operations and energy transformations via Power-to-Gas and Gas-to-Power by coupling biogas plants with biomethanation and CHP units.

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In the globalising business environment ever fewer market areas remain unknown. Mongolia is yet only considered as an isolated strip between two power states. The purpose of this study is to put Mongolia on the map of academic business research. This is done by describing the transforming network of a foreign company operating in Mongolia. The objective of the study is approached through a case study, which presents the transformation of a Finnish company operating in Mongolia. This study aims at providing understanding on how the foreign case company observes the transformations of its network. The transformation within the case company is reflected to the transformations that occur in the Mongolian business environment. This study was conducted through a qualitative, intrinsic case study approach. The empirical data was gathered by using the method of network pictures. The network pictures were completed with the assistance of themed interviews. In order to be able to analyse the transformation within a network, three different time periods were observed: the past period around 2000, the present around 2014, and the estimated future around 2020. The data was collected from four executives positioned either in Finland, Russia or Mongolia. The respondents have a long experience within the case company, they hold managerial position, and therefore were able to offer valuable data for this study. The analytical framework used to analyse the collected data was built on the industrial network model, the ARA (actors-resources-activities)-model. The study shows that the changing business environment of Mongolia was utilised by the case company. In order to better meet the transforming customer wishes, the case company transformed from being a retailer to being a manufacturer. The case company was able to become a pioneer in the market. Thus, the case company has undergone similar kind of rapid transformation as the economy of Mongolia in entirety. This study shows that the general nature of the ARA-model makes it usable for new research contexts. The initial ARA-model offers a way to identify the dimensions of a network and a mean to understand these dimensions. The ARA-model can be applied to different contexts and to all time dimensions, past, present and future. The managerial recommendations offered in this study are directed towards the managers that plan to start operations in Mongolia. While this study is the first of its kind, it offers a good starting point for the future research on the change of Mongolian business networks. Valuable information could, for example, be obtained from a comparative study between the case company of this study and a multinational mining company operating in Mongolia.

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The State and the economy in South Korea: from the developmentist state to the Asian crisis and later recovery. The article focuses on the institutions of South Korean capitalism and on the interactions between the state and the economy. The economic model in South Korea was characterized by a very interventionist state, which played a very active role in the process of industrialization. However, South Korea suffered a severe crisis in 1997, attributed by many authors to the distortions inherent to strong state intervention. The article shows that the crisis was a result of the combination between internal economic fragilities and a rapid process of financial deregulation, which undermined the state's capacity of control. The crisis, nevertheless, does not disqualify the role of the national institutions in the very successful process of industrialization. Despite the reforms, the Korean capitalism conserves much of the previous model of business organization and industrial relations. The state continues strong and played active role in the process of economic reforms. There are, nevertheless, doubts about the impacts of the reforms and the new configuration of Korean capitalism. They will depend on the current transformations in world economy and in the East Asian countries.

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Weber and Schumpeter: the Economic action of the entrepreneur. Is there any specificity to be raised in the relations established between entrepreneurs and institutions? Recently, the term entrepreneurship is being widely employed. Enterprising is not anymore a restricted activity to the private sector, but also the Third Sector and the Public Administration. It does not only circumscribe the space of innovation, but also of the adapting changes. In this sense, such elastic concept runs the risk to lose consistency. It seems to be appropriate, therefore, to rescue the meaning that many authors, considered classic in Social Sciences, had attributed to the subject, to show that, although deep socioeconomic transformations occurred since Schumpeter wrote the Theory of the Economic Development, is still necessary to emphasize a basic dimension of the enterprising action: resistance and institutional conflict.

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Measuring racial inequalities in the labor market. How much racial inequality is there in Brazilian labor market? What has been the impact of the latest transformations in work relations on it? Can we compare the Brazilian situation to other countries? These questions don't have today an objective answer. This is due, mostly, to the absence of measures which could allow us to make long term and regional comparisons of different racial inequalities situations. Our proposal is to provide new indicators to evaluate racial inequalities in both the occupational and income structure in Brazil. Our results show that whites/non-whites gaps widened since the 1980s. They allow us to affirm, in addition, that racial inequalities are today worst in Brazil than in countries that adopted affirmative action laws to fight discrimination.

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This paper analyzes the causes of the slow recovery of the US economy since the financial crisis and Great Recession of 2008-9. Fallen house values and excessive household debts continue to depress consumer spending, while corporations are failing to invest in spite of record profits. The increasingly unequal distribution of income limits demand, while long-term structural transformations continue to erode employment creation. An expansionary monetary policy has been incapable of sparking a more robust recovery and fiscal policy has been shifted to an austerity stance. In this context, Brazil and other emerging market nations cannot count on the United States to continue to be the leading source of global demand as it was in previous decades.

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This thesis examines the Midnight Express phenomenon focusing on the film's reception by audiences in Europe, North America, and Turkey between 1978-2003. Using and enhancing the "historical materialist approach" to film reception developed by Janet Staiger, the thesis considers the historical determinants of the film's nationally and culturally differential readings in different periods and of the transformations in those readings. The thesis argues that while Midnight Express was most likely read in the late 1970s as an attempt to reaffirm American social identity by projecting Turks as an instance of the negative Other, there has been an important shift in the reception of the film in the West during the 1990s due to the changes in the discursive contexts in which the film has been circulating. One does not observe any specific reference to Turkish prisons as a part of the issue of human rights violations in Turkey in the initial reception of the film by European and American critics, whereas these issues appear to be important constituents of a particular reception of the film in the West in the present. The thesis explains this shift by pointing to the constitution of a particular discourse on human rights violations in Turkey after 1980, and especially throughout the 1990s, which has become a part of the discursive repertoires of the Western audience. Therefore, the thesis argues that today, Midnight Express functions as a more legitimate political statement about Turkey in the eyes of some Western audiences than it had been in the 1970s. On the other hand, parallel to the increasing desire of Turkey to connect itself to the West, particularly to become a member of the European Union, one observes an immense increase in the belief in and defense against the negative effects of Midnight Express on Turkey's international representation since the 1990s. The historical and current discourses that audiences, both in Turkey and abroad, bring into play suggest that these audiences engage with Midnight Express by assuming or denying not only the subject positions constructed by the film text but also certain history-specific extra-filmic subject positions produced by other social and discursive formations.

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All life is suffering. Life is the pursuit ofhappiness. These are two foundational Buddhist dictums that, in their simplicity, I have entirely misunderstood regarding their depth, misreading them as contradictory. Indeed, my superficial interpretations led me to Thoreau's life ofquiet desperation and deep depression. We come to know and bring understanding to our lives by storying them. My own Hero's Journey, the path from my egoic selftoward the universal Self, can be understood as the resultant translations and transformations. Inevitably each of us is involved in such a story, though most are unaware of the stages along our own Hero's journey. ' Narrative honours writing as a means of knowing. The contemplative reflection allows insight into our imprisoning paradigms, beliefs, behaviours, and blind spots. My research revisits and explores nodal experiences along my Hero's Journey through 4 categories: self, society, soil, and Self. While the value of this process of narrative inquiry lay in its ability to come to know and understand one's self, perhaps its greater value is of a more universal nature. My inquiry, while adding to the body of academic educational narrative literature, may also illuminate a path to educators, students, and all interested, encouraging a response to the call of their own Hero's journey. I am a teacher/learner in a jail setting, working with youth between the ages of 12 and 18 who have committed crimes such as armed robbery, assault, rape, and murder. As this thesis follows my continual development from egoic self/teacher/learner to universal Self/Teacher/Learner, it also enables me to both consciously and unconsciously open the ways in which I expand my care, compassion, and love to work with at-risk youth.

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The mechanistic aspects of the 19-hydroxy1ation and aromatization of androgens were investigated. Fungal, bacterial and mammalian enzymatic activities were studied in this regard . The fungus Pell i cular~ fi1amentosa metabolized androst-4-ene-3 , 17-dione to the corresponding 110<' , 11 f and 14 0( hydroxylated derivatives. No ~19- hydroxylated products were isolated, although this transformation was previously observed for the C21-steroids . The intestinal bacterium Clostridi um paraputrific~ had been reported to aromatize androsten-4-ene-3,17-dione. In the present study, however, only the ring A reduced products , 17(3 - hydroxy-5f -andro8tane- 3-one and 5f-androstane-3,17-dione , were recovered . Human placental microsomes contain substantial aromatase activity and were employed in an effort to elucidate some of the mechanistic details of aromatization. Selectively deuterated steroidal substrates were employed as a probe in order to distinguish b'!tween certain of the mechanisms proposed for aromatization . Retention of deuterium at C4 and C6 was observed. It was concluded that no free intermediates allowing for loss of hydrogen from either of these two positions are implicated in this process . The involvement of a Schiff base enzyme-sup strate complex in aromatization was examined using the substrate 17f - hydroxyandrost-4-ene-3-one- 3_ 1BO. Since no loss of label was ob~erved, the implication of a Schiff base was discounted . Mixed label1ir~ studies were performed in order to determine if hydroxylation at C19 is a rate-determining process in aromatization . Isotope effects of 2 .1 and 1.7 were determined for the conversion of 17f - hydroxyandrost-4-ene-J-one-19,19,19-dJ and -19-dl respectively to estrogens. It was concluded from this that 19-hydroxylation is at l east a partially rate-determinjng process in aromatization. A homoenb~ation mechanism for 19-hydroxylation was not supported by the data obtained in this s tudy. In vitro 1JC NMR monitoring using l7f-hydroxyandrost-4-ene-Jone- 19-l3C was found not to be a successful approach in the study of steroid transformations, owing in part t o their low solubility in the incubation medium.

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New and robust methodologies have been designed for palladium-catalyzed crosscoupling reactions involving·a novel·class oftertiary phosphine ligand incorporating a phospha-adamantane framework. It has been realized that bulky, electron-rich phosphines, when used as ligands for palladium, allow for cross-coupling reactions involving even the less reactive aryl halide substrates with a variety of coupling partners. In an effort to design new ligands suitable for carrying out cross-coupling transformations, the secondary phosphine, 1,3,5,7-tetramethyl-2,4,8-trioxa-6phosphaadamantane was converted into a number of tertiary phosphine derivatives. The ability of these tertiary phosphaadamantanes to act as effective ligands in the palladiumcatalyzed Suzuki cross-coupling was examined. 1,3,5,7-Tetramethyl-6-phenyl-2,4,8trioxa- 6-phosphaadamantane (PA-Ph) used in combination with Pdz(dba)3permitted the reaction of an array of aryl iodides, bromides and chlorides with a variety arylboronic acids to give biaryls in good to excellent yields. Subsequently, palladium complexes of PA-Ph were prepared and isolated in high yields as air stable palladium bisphosphine complexes. Two different kinds of crystals were isolated and upon characterization revealed two complexes, Pd(PA-Ph)z.dba and Pd(PA-Ph)zOz. Preliminary screening for their catalytic activity indicated that the former is more reactive than the latter. Pd(PAPh) z.dba was applied as the catalyst for Sonogashira cross-coupling reactions of aryl iodides and bromides and in the reactions of aryl bromides and chlorides with ketones to give a-arylated ketones at mild temperatures in high yields.