998 resultados para Kentucky Auxiliary Bible Society.


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This thesis explores the relationship between humans and ICTs (information and communication technologies). As ICTs are increasingly penetrating all spheres of social life, their role as mediators – between people, between people and information, and even between people and the natural world – is expanding, and they are increasingly shaping social life. Yet, we still know little of how our life is affected by their growing role. Our understanding of the actors and forces driving the accelerating adoption of new ICTs in all areas of life is also fairly limited. This thesis addresses these problems by interpretively exploring the link between ICTs and the shaping of society at home, in the office, and in the community. The thesis builds on empirical material gathered in three research projects, presented in four separate essays. The first project explores computerized office work through a case study. The second is a regional development project aiming at increasing ICT knowledge and use in 50 small-town families. In the third, the second project is compared to three other longitudinal development projects funded by the European Union. Using theories that consider the human-ICT relationship as intertwined, the thesis provides a multifaceted description of life with ICTs in contemporary information society. By oscillating between empirical and theoretical investigations and balancing between determinist and constructivist conceptualisations of the human-ICT relationship, I construct a dialectical theoretical framework that can be used for studying socio-technical contexts in society. This framework helps us see how societal change stems from the complex social processes that surround routine everyday actions. For example, interacting with and through ICTs may change individuals’ perceptions of time and space, social roles, and the proper ways to communicate – changes which at some point in time result in societal change in terms of, for example, new ways of acting and knowing things.

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A novel ZVS auxiliary switch commutated variation for all DGDC converter topologies has been proposed in 2006. With proper designation of the circuit variables (throw current I and the pole voltage V), all these converters are seen to be governed by an identical set of equations. With idealized switches, the steady-state performance is obtainable in an analytical form. The conversion ratio of the converter topologies is obtained. A generalized equivalent circuit emerges for all these converters from the steady-state conversion ratio. It also provides a dynamic model as well. With these generalized steady-state equivalent circuits, small signal analysis of these converters may be carried out readily. It enables one to use the familiar state space averaged results of the standard PWM DGDC converters for the resonant counterparts. Th dc and ac models reveals that dc and low frequency behaviour of the proposed family of converters is similiar to that of its PWM parent

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Recent trends in the use of dispersed solid electrolytes and auxiliary electrodes in galvanic cells have increased the need for assessment of materials compatibility. In the design of dispersed solid electrolytes, the potential reactions between the dispersoid and the matrix must be considered. In galvanic cells, possible interactions between the dispersoid and the electrode materials must also be considered in addition to ion exchange between the matrix and the electrode. When auxiliary electrodes, which convert the chemical potential of a component present at the electrode into an equivalent chemical potential of the neutral form of the migrating species in the solid electrolyte are employed, displacement reactions between phases in contact may limit the range of applicability of the cell. Examples of such constraints in the use of oxide dispersoids in fluoride solid electrolytes and NASICON/Na2S couple for measurement of sulphur potential are illustrated with the aid of Ellingham and stability field diagrams.

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Mesoscale weather phenomena, such as the sea breeze circulation or lake effect snow bands, are typically too large to be observed at one point, yet too small to be caught in a traditional network of weather stations. Hence, the weather radar is one of the best tools for observing, analyzing and understanding their behavior and development. A weather radar network is a complex system, which has many structural and technical features to be tuned, from the location of each radar to the number of pulses averaged in the signal processing. These design parameters have no universal optimal values, but their selection depends on the nature of the weather phenomena to be monitored as well as on the applications for which the data will be used. The priorities and critical values are different for forest fire forecasting, aviation weather service or the planning of snow ploughing, to name a few radar-based applications. The main objective of the work performed within this thesis has been to combine knowledge of technical properties of the radar systems and our understanding of weather conditions in order to produce better applications able to efficiently support decision making in service duties for modern society related to weather and safety in northern conditions. When a new application is developed, it must be tested against ground truth . Two new verification approaches for radar-based hail estimates are introduced in this thesis. For mesoscale applications, finding the representative reference can be challenging since these phenomena are by definition difficult to catch with surface observations. Hence, almost any valuable information, which can be distilled from unconventional data sources such as newspapers and holiday shots is welcome. However, as important as getting data is to obtain estimates of data quality, and to judge to what extent the two disparate information sources can be compared. The presented new applications do not rely on radar data alone, but ingest information from auxiliary sources such as temperature fields. The author concludes that in the future the radar will continue to be a key source of data and information especially when used together in an effective way with other meteorological data.

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Since begging East European Roma became a common view in the streets of larger Nordic cities, vivid discussions about their presence and activities have been carried out in the mass media. This thesis examines the public debates in Finland and Norway through a discursive analysis and comparison of press content from the two countries. The aim of the study is firstly to identify the prominent discourses which construct certain images of the beggars, as well as the elements and internal logics that these discourses are constructed around. But in addition to scrutinizing representations of the Roma, also an opposite perspective is applied. In accordance with the theoretical concept of ‘othering’, debates about ‘them’ are assumed to simultaneously reveal something significant about ‘us’. The second research question is thus what kind of images of the ideal Finnish and Norwegian societies are reflected in the data, and which societal values are salient in these images. The analysis comprises 79 texts printed in the main Finnish and Norwegian quality newspapers; Helsingin Sanomat and Aftenposten. The data consists of news articles, editorials, columns and letters to the editor from a three-month period in the summer of 2010. The analysis was carried out within the theoretical and methodological framework of critical discourse analysis as outlined by Norman Fairclough. A customized nine-step coding scheme was developed in order to reach the most central dimensions of the texts. Seven main discourses were identified; the Deprivation-solidarity, Human rights, Order, Crime, Space and majority reactions, Authority control, and Authority critique discourse. These were grouped into two competing normative stances on what an ideal society looks like; the exclusionary and the inclusionary stance. While the exclusionary stance places the begging Roma within a frame of crime, illegitimate use of public space and threat to the social order, the other advocates an attitude of solidarity and humanitarian values. The analysis points to a dominance of the former, although it is challenged by the latter. The Roma are “individualized” by quoting and/or presenting them by name in a fair part of the Finnish news articles. In Norway, the opposite is true; there the beggars are dominantly presented as anonymous and passive. Overall, the begging Roma are subjected to a double bind as they are faced with simultaneous expectations of activity and passivity. Theories relating to moral panics and ‘the good enemy’ provide for a deepened understanding of the intensity of the debates. Keywords: East European Roma, begging, media, newspapers, Helsingin Sanomat, Aftenposten, critical discourse analysis, Norman Fairclough, othering, ideal society, moral panics, good enemy, double bind, Finland, Norway

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The silk gland of Bombyx mori is a terminally differentiated tissue in which DNA replication continues without cell or nuclear division during larval development. DNA polymerase-delta activity increases in the posterior and middle silk glands during the development period, reaching maximal levels in the middle of the fifth instar larvae. The enzyme has been purified to homogeneity by a series of column chromatographic and affinity purification steps. It is a multimer comprising of three heterogeneous subunits, M(r) 170,000, 70,000, and 42,000. An auxiliary protein from B. mori silk glands, analogous to the proliferating cell nuclear antigen, enhances the processivity of the enzyme and stimulates catalytic activity by 3-fold. This auxiliary protein has also been purified to homogeneity. It is a dimer comprised of a single type M(r) 40,000 subunit. Polymerase-delta possesses an intrinsic 3' --> 5' exonuclease activity which participates in proofreading by mismatch match repair during DNA synthesis and is devoid of any primase activity. DNA polymerase-delta activity could be further distinguished from polymerase-alpha from the same tissue based on its sensitivity to various inhibitors and polyclonal antibodies to the individual enzymes. Like DNA polymerase-alpha, polymerase-delta is also tightly associated with the nuclear matrix. The polymerase alpha-primase complex could be readily separated from polymerase-delta (exonuclease) in the purification protocol adopted. DNA polymerase-delta from B. mori silk glands resembles the mammalian delta-polymerases. Considering that both DNA polymerase-delta and -alpha are present in nearly equal amounts in this highly replicative tissue and their close association with the nuclear matrix, the involvement of both the enzymes in the chromosomal endoreplication process in B. mori is strongly implicated.

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The silk gland of Bombyx mori, an endomitotically replicative tissue shows high levels of DNA polymerases alpha, delta, and epsilon activities. The ratio of polymerase alpha to that of delta plus epsilon is maintained at 1.1 to 1.3 in both the posterior and middle silk glands for the entire duration of late larval development. The three activities copurify in the initial stages of fractionation through phosphocellulose and DE52 but polymerase alpha gets resolved from the others on hydroxylapatite column. Separation between polymerase delta and epsilon is achieved by chromatography on QAE-Sephadex. DNA polymerase epsilon is a heterodimer comprising of 215- and 42-kDa subunits. The activity is maximum at pH 6.5 and the Km values for dNTPs vary between 3-9 microM. The enzyme possesses an intrinsically associated exonuclease activity which functions in the mismatch repair during DNA synthesis. Both polymerase and 3'-->5' exonuclease activities are associated with the 215-kDa subunit. By itself, DNA polymerase epsilon is processive and the catalytic activity is not enhanced by externally added bPCNA (Bombyx-proliferating cell nuclear antigen, an auxiliary protein for DNA polymerase delta). The enzyme resembles polymerase delta in having the exonuclease activity and in its response to aphidicolin or substrate analogs, but could be distinguished from the latter by its lack of response to the bPCNA and sensitivity to dimethyl sulfoxide. The two enzymes show partial immunological cross-reactivity with each other but no immunological relatedness to polymerase alpha. The absence of the repair enzyme DNA polymerase beta and the presence of substantial levels of polymerase epsilon in the silk glands suggest a possible role for the latter in DNA repair in that tissue.

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New steroid-based chiral auxiliaries 6, 9, and 12 have been synthesized from readily available cholic acid. These new chiral auxiliaries place the reactive and the shielding sites in a 1,5 relationship to each other. Diels-Alder reaction of cyclopentadiene with corresponding acrylate esters (7, 10, and 13) have been examined. Acrylates 7 and 10 yielded cycloadducts with 29-88% diastereomeric excess with excellent endo selectivity in the presence of an excess of Lewis acids such as AlCl3, BF3.OEt(2), FeCl3, SnCl4, TiCl4, and ZnCl2. Treatment of acrylate 7 with cyclopentadiene in the presence of BF3.OEt(2) at -80 degrees C gave the endo adduct (>99%) with 88% de. Lewis acid catalyzed and uncatalyzed reactions of acrylates 7 and 10 with cyclopentadiene yielded cycloadducts with opposite stereochemistry. The chiral auxiliary was recovered in a nondestructive manner only via iodolactonization. Acrylate ester of alcohol 12 did not show any selectivity in either catalyzed and uncatalyzed reactions with cyclopentadiene. The presence of a flat aromatic surface at C-7 of the steroid was found to be essential to effect high diastereoselection.

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The higher substrate and chiral auxiliary concentration is a pre-requisite to obtain efficient separation of H-1 NMR signals of enantiomers. The higher concentration of chiral lanthanide shift reagents provides broadened spectral lines resulting in a severe loss of resolution between the enantiomer resonances. In order to circumvent such difficulties, herein we present the application and the usefulness of a selective F-1 decoupled correlation (COSY) experiment which yields proton decoupled proton spectra in the indirect dimension. The potentiality of the experiment is demonstrated on several chiral compounds possessing different functional groups, employing either a lanthanide shift reagent or a solvating reagent as chiral auxiliaries. (C) 2011 Elsevier B.V. All rights reserved.

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Abstract: Activities in the spinel solid solution FexMg1-xAl2O4 saturated with alpha-Al2O3 have been measured for the compositional range 0 < X < 1 between 1100 and 1350 K using a bielectrolyte solid-state galvanic cell, which may be represented as Pt, Fe + FexMg1-xAl2O4 + alpha-Al2O3//(Y2O3)ThO2/ (CaO)ZrO2//Fe + FeAl2O4 + alpha-Al2O3, Pt Activities of ferrous and magnesium aluminates exhibit small negative deviations from Raoult's law. The excess free energy of mixing of the solid solution is a symmetric function of composition and is independent of temperature: Delta G(E) = -1990 X(1 - X J/mol. Theoretical analysis of cation distribution in spinel solid solution also suggests mild negative deviations from ideality. The lattice parameter varies linearly with composition in samples quenched from 1300 K. Phase relations in the FeO-MgO-Al2O3 system at 1300 K are deduced from the results of this study and auxiliary thermodynamic data from the literature. The calculation demonstrates the influence of intracrystalline ion exchange equilibrium between nonequivalent crystallographic sites in the spinel structure on intercrystalline ion exchange equilibrium between the monoxide and spinel solid solutions (tie-lines). The composition dependence of oxygen partial pressure at 1300 K is evaluated for three-phase equilibria involving the solid solutions Fe + FexMg1-xAl2O4 + alpha-Al2O3 and Fe + FeyMg1-yO + FexMg1-xAl2O4. Dependence of X, denoting the composition of the spinel solid solution, on parameter Y, characterizing the composition of the monoxide solid solution with rock salt structure, in phase fields involving the two solid solutions is elucidated. The tie-lines are slightly skewed toward the MgAl2O4 corner.

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Conventional thyristor-based load commutated inverter (LCI)-fed wound field synchronous machine operates only above a minimum speed that is necessary to develop enough back emf to ensure commutation. The drive is started and brought up to a speed of around 10-15% by a complex `dc link current pulsing' technique. During this process, the drive have problems such as pulsating torque, insufficient average starting torque, longer starting time, etc. In this regard a simple starting and low-speed operation scheme, by employing an auxiliary low-power voltage source inverter (VSI) between the LCI and the machine terminals, is presented in this study. The drive is started and brought up to a low speed of around 15% using the VSI alone with field oriented control. The complete control is then smoothly and dynamically transferred to the conventional LCI control. After the control transfer, the VSI is turned off and physically disconnected from the main circuit. The advantages of this scheme are smooth starting, complete control of torque and flux at starting and low speeds, less starting time, stable operation, etc. The voltage rating of the required VSI is very low of the order of 10-15%, whereas the current rating is dependent on the starting torque requirement of the load. The experimental results from a 15.8 hp LCI-fed wound field synchronous machine are given to demonstrate the scheme.