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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
941

Der Einfluss der Social-Network-Site Facebook auf die Bildungspartizipation und das Konsumverhalten ihrer Nutzer: Eine quantitativ-empirische Studie

Sterl, Sebastian, Graupner, Marc 14 July 2014 (has links)
In der vorliegenden Forschungsarbeit – im Charakter einer Pionierstudie auf diesem Gebiet – wird mittels selbstkonstruiertem Onlinesurvey untersucht, inwiefern die Social-Network-Site Facebook die Bildungspartizipation und das Konsumverhalten ihrer Nutzer beeinflusst und verändert. Nach Definition eines sozialen Netzwerks, einer Social-Network-Site und definitorischer Eingliederung von Facebook als solche wird die Sozialplattform selbst historisch und faktisch erklärt und der bisherige Forschungsstand zusammengetragen. Zur weiteren Hypothesenformulierung dienen für die Bildungspartizipation Marotzkis strukturale Bildungstheorie (1990) und Banduras kognitive Lerntheorie (1979), für das Konsumverhalten ebenfalls Banduras sozial-kognitive Lerntheorie (1971; 1976; 1986), Heiders Balancetheorie (1946) und Festingers soziale Vergleichstheorie (1954). Nach äußerst umfangreicher Operationalisierung, Rekodierung und Skalenbildung, univariater und bivariater Analyse, Drittvariablenkontrolle und Mediationsprüfung werden im Regressionsabschnitt alle fünf Prädiktoren der Haupthypothesen der Bildungspartizipation und drei der fünf Haupthypothesen des Konsumverhaltens bestätigt. Die „Anzahl an Facebook-Freunden“, „Neue Facebook- Freunde“, „Daten aus der Vergangenheit“, „Lesen bildungsrelevanter Aspekte“ und die „Facebook-Nutzungshäufigkeit (pro Woche)“ beeinflussen somit signifikant positiv die Bildungspartizipation. Die „Neigung zu positiv geschlossenen Triaden“, die „Relevanz positiver Meinungen der Vergleichspersonen“ und die „Beobachtung positiver Signale Statushoher“ beeinflussen positiv-signifikant das Konsumverhalten, wobei jedoch im Endmodell die „Beobachtung negativer Konsumerfahrungen“ und die „Relevanz der Ähnlichkeit von Vergleichspersonen“ keinen statistisch gesicherten Effekt mehr aufweisen. Der überwiegende Teil der vorab gebildeten Unterhypothesen – als theoretische Zusatzannahmen fundiert – werden bestätigt. Als weiteres statistisches Instrument wird ein Künstliches Neuronales Netz als Regressionsfunktionsapproximator eingesetzt, das bemerkenswert genau die Einflussstärken der Haupthypothesenvariablen validiert. / Nowadays, the social network site Facebook preferably serves as an appropriate medium of communication and as adviser on issues about daily life. Thus, recent social scientists have plenty of reasons to investigate the research field Facebook, the connections amongst its members, their cognitive structures and way of behaving which is frequently not intended. Through an online survey, including 1,358 German respondents, the influence of Facebook on educational participation and consumer behaviour is analysed. According consumer behaviour as dependent variable, Heider´s Balance Theory (1946), Bandura´s Social Cognitive Theory (1971, 1976, 1986), and Festinger´s Theory of Social Comparison Processes (1954), including theoretical continuations for each of these, are used. In order to derivate hypotheses for educational participation Marotzki´s Strukturale Bildungstheorie (1990), further extensions and Bandura’s Social Cognitive Learning Theory are taken. To sum up, tending to positively closed triads, relevant positive opinions of persons of comparison, and observing positively social signals from persons with a high status on Facebook significantly and positively influence consumer behaviour. Surprisingly, there is no significant influence from similarity to persons of comparison and observations of negative consumer´s experience. All hypotheses concerning educational participation could be confirmed: For instance, the more often a person gets new Facebook friends or the more often friends post visible educational aspects (i.e. newspaper articles or similar), the higher is educational participation on Facebook. These results, analysed by a regression analysis, are checked by an alternative method which is rarely used in that context. Using an artificial neural network (multilayer perceptron) a sensitivity analysis is conducted. Interestingly, the rank order of beta coefficients is almost reproduced. The existing study which was carried out at the Institute of Sociology in Leipzig is a pilot experiment in respect of both theoretical and methodical aspects. There are exploratively connections between social-psychological theory and consumer behaviour and educational participation on Facebook, supported by an extensive implementation of control variables.
942

Yngre järnålderns rituella mötesplatser : En jämförande studie av Lilla Ullevi och Anundshög / The ritual meeting places of the Late Iron Age : A comperative studie of Lilla Ullevi and Anundshög

Dellner, Helena January 2023 (has links)
Syftet med den här uppsatsen är att utmana tolkningar av arkeologiskt material som kan spegla rituella handlingar under yngre järnålder. Begreppet kult har blivit ett populärt samlingsbegrepp inom arkeologin men saknar ofta en tydlig definition. Religiösa tolkningar av rituellt material verkar ha företräde framför profana tolkningar – amulettringar tolkas gärna som religiös rekvisita istället för som objekt använda vid juridiciella aktiviteter. Uppsatsen kommer att belysa hedern och alliansernas betydelse i det forntida samhället som en motvikt till den fornnordiska religionen samt propagera för att en plats kan ha använts för både sakrala och profana ändamål. Fokus i studien ligger på kultplatsen Lilla Ullevi samt tingsplatsen Anundshög i Mälardalen. Det arkeologiska materialet jämförs och analyseras med hjälp av litteratur från arkeologi, ortnamnsforskning och religionshistoria. Resultatet visar att platsernas rituella funktioner inte kan åtskiljas genom det arkeologiska materialet. Kultplatsen och tingsplatsen passar båda in på den i norrön litteratur benämnda Vi-platsen, en fredad plats avsedd för rituella handlingar. / The purpose of this essay is to challenge interpretations of archaeological material that may reflect ritual actions during the Late Iron Age. The term cult has become a popular collective term in archeology but often lacks a clear definition. Religious interpretations of ritual material seem to take precedence over profane interpretations – amulet rings are often interpreted as religious props instead of objects used in juridical activities. The essay will highlight the importance of honor and alliances in ancient society as a counterweight to the Old Norse religion, as well as propagandize that a place may have been used for both sacred and profane purposes. The focus of the study is on the cult site Lilla Ullevi and the court site Anundshög in Mälardalen. The archaeological material is compared and analyzed with the help of literature from archaeology, place name research and religious history. The results show that the ritual functions of the sites cannot be separated through the archaeological material. The cult site and court site both fit into what is called the Vi-place in Norse literature, a protected place intended for ritual acts.
943

Tomträttsupplåtelse i praktiken / Site leasehold in practice

Bohlin, Jennifer January 2018 (has links)
I Sverige har det sedan år 1907 varit möjligt att upplåta en fastighet med tomträtt. Detta är en särskild form av nyttjanderätt som innebär att tomträttshavaren får rätt att nyttja en statlig eller kommunal fastighet på liknande villkor som äganderätt mot en årlig avgäld. Avsikten med införandet av tomträtt var att ge privatpersoner möjlighet att få tillgång till mark i bostadssyfte till ett lägre pris än vid ett fastighetsköp samt att låta kommun eller stat behålla marken. På så sätt uppmuntrades byggverksamheten samtidigt som staten eller kommunen kunde påverka ändamålet med fastigheten, behålla värdestegringen på marken samt få en årlig avgäld.  Trots att tomträtt är ett gammalt institut föreligger fortfarande en del oklarheter och frågetecknen kring upplåtelseformen och dess tillämpning i praktiken. Då denna osäkerhet kan tänkas bidra till att stat och kommuner väljer bort tomträtt som upplåtelseform genomförs därför detta arbete med målet att tillhandahålla information och vägledning i ämnet och göra den mer tillgänglig för aktörer som vill börja tillämpa tomträtt. / Since 1907 in Sweden, it has been possible to grant a property with site lease hold. This is a special form of usufruct that entitles the leaseholder to use land owned by the state or a municipality on similar terms as ownership against an annual rate. The purpose of this legislation was to give individuals the opportunity to access land for residential purposes at a lower price than in a property purchase as well as to keep the municipality or state retaining the land. This encouraged construction activities while at the same time the state or municipality could influence the purpose of the property, maintain the value increase on the land and receive an annual installment. Although site lease hold is an old term, some uncertainties and question still exist regarding the form of the tenure and its application in practice. As this uncertainty contributes to the fact that the state and municipalities choose to disregard it as a form of tenure, this essay is therefore carried out with the aim of providing information and guidance on the subject and making it more accessible to actors who wish to start using site lease hold.
944

Caractérisation moléculaire du système de recombinaison XerH/difH chez Campylobacter jejuni

Benmohamed, Amal 08 1900 (has links)
Chez les bactéries à chromosomes circulaires, le crossing-over introduit par la recombinaison homologue peut conduire à des échanges de chromatides soeurs. Des nombres impairs de ces échanges aboutissent à la dimérisation des deux chromatides nouvellement répliquées compromettant ainsi leur ségrégation. Par conséquent, la plupart des bactéries utilisent le système de recombinaison spécifique de site Xer pour convertir les dimères de chromosomes et de plasmides en monomères stables. Ce système comporte deux recombinases de la famille Tyrosine recombinase, XerC et XerD, agissant sur le site dif. Cependant, quelques ε-protéobactéries n’ont besoin que d'une seule recombinase XerH agissant sur un site difH. Il parait intéressant d’étudier le système de recombinaison XerH de Campylobacter jejuni, surtout que l'augmentation spectaculaire de l'incidence de campylobactériose est alarmante. Cette étude vise à mieux comprendre comment la protéine XerH catalyse la réaction de recombinaison au niveau du site difH en mettant en évidence les séquences indispensables pour la liaison et le clivage. Grâce à ces expériences, nous avons pu confirmer que XerH est capable de se lier à la séquence entière difH; XerH est capable de cliver les deux brins supérieurs et inférieurs de difH avec une réaction plus efficace au niveau du brin inférieur; les nucléotides conservés du site de liaison sont indispensables pour la réaction de liaison; la modification de la longueur de l’espaceur améliore la réaction de liaison et de clivage et les modifications apportées au site de clivage prédit ont aboli la réaction de liaison et affecté la réaction de clivage au niveau du brin supérieur et inférieur du site difH. Ces expériences aideront à comprendre comment la recombinase XerH/difH contrôle la résolution des dimères chromosomiques chez Campylobacter jejuni en identifiant les séquences et les facteurs indispensables pour qu’un certain système soit fiable. Notre étude représente un pas vers l’avant pour comprendre un mécanisme important chez un agent pathogène ayant un grand impact sur la santé publique. / In bacteria with circular chromosomes, cross-over induced by homologous recombination can lead to sister chromatid exchanges, odd numbers of these exchanges result in dimerization of the two newly replicated chromatids compromising their segregation. Therefore, most bacteria use the Xer site-specific recombination system to convert chromosomal and plasmid dimers into stable monomers. This system involves two recombinases of the Tyrosine recombinase family, XerC and XerD, acting at the dif site. However, some ε-proteobacteria require only one XerH recombinase acting on a difH site. It seems interesting to study the XerH recombination system of Campylobacter jejuni, especially since the dramatic increase in the incidence of campylobacteriosis is alarming. This study aims to better understand how the XerH protein catalyzes the recombination reaction at the difH site by identifying the sequences required for binding as well as the factors regulating this reaction. As a result of these experiments, we were able to confirm that XerH is able to bind to the entire difH sequence; it is able to cleave both the top and bottom strands of difH with a more efficient reaction at the bottom strand; The conserved nucleotides in the binding site are essential for the binding reaction, modification of the spacer length improves the binding and cleavage reaction, and modifications in the predicted cleavage site abolished the binding reaction and affected the cleavage reaction at both the top and bottom strands of the difH site.. These experiments will help to understand how the XerH/difH recombinase controls the resolution of chromosomal dimers in Campylobacter jejuni by identifying the essential sequences and factors required for a certain system to be reliable. Our study represents a step forward in understanding an important mechanism in a pathogen with great impact on public health.
945

Estimating site susceptibility to Scotch broom dominance in young Douglas-fir plantations for control prioritization in western Washington, USA

Boyle, Grady John 11 October 2023 (has links)
Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii), a keystone species in western Washington, faces threats on plantations across this region from the invasive species Scotch broom (Cytisus scoparius (L.) Link), whose invasions on recently established stands can lead to mortality of Douglas-fir through overtopping. The susceptibility of sites to Scotch broom achieving dominance over Douglas-fir has been demonstrated as highly site dependent, however the site conditions that cause this have not yet been identified. Scotch broom has a demonstrated average maximum height of 3m, thus, after Douglas-fir exceeds this height, its risk of being overtopped is significantly reduced. This thesis strives to identify sites that were at the greatest risk Douglas-fir being overtopped by Scotch broom by first, identifying what factors improved growth of Douglas-fir during the period when they are at the greatest risk, and second, identifying factors that led to Douglas-fir outcompeting Scotch broom on sites they cohabitated. In Chapter 1, we utilized LiDAR scans, Soil Survey Geographic Database characteristics, and management histories to identify conditions that improved growth for Douglas-fir in ages 3-8. Individual tree detection was used to measure Douglas-fir heights, and a correction algorithm for LiDAR measured young Douglas-fir heights was established from field validation data. We identified that young Douglas-fir had improved growth on sites with lower elevation, flatter slopes, and finer textured soils. The factors identified were then transformed into four potential site index models based on mean stand elevation class, Mean stand elevation class and clay class, textural class and slope class, and textural class and Mean stand elevation class. In Chapter 2, we used paired field plots to examine Douglas-fir and Scotch broom competition on 19 sites across western Washington. Each site had 2 plots with only Douglas-fir and 2 plots with Douglas-fir and Scotch broom. Elevation, soil texture, and soil nutrient composition for carbon, nitrogen and available phosphorous were examined for influence on height and growth rate of both species. We identified that Scotch broom presence was negatively related to Douglas-fir height growth and that sites with either higher percentages of silt, lower concentrations of phosphorous, or higher percentages of Carbon were more likely to have growth patterns close to or exceeding Scotch broom. / Master of Science / Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) is a valuable timber species across western Washington that is commonly grown in plantations. In western Washington when Douglas-fir are planted on a site they often face competition from the invasive shrub Scotch broom (Cytisus scoparius (L.) Link). When Scotch broom invasions occur on a recently planted Douglas-fir stands, they can cause death of the trees if Scotch broom plants grow taller than the young Douglas-fir and obstruct their access to light, a process called overtopping. The risk of Douglas-fir being overtopped has been shown to be dependent on location, however what causes a location to be at risk of overtopping is yet unknown. Scotch broom has a demonstrated average maximum height of 3m, thus, after Douglas-fir exceeds this height, its risk of being overtopped is significantly reduced. This study aims to identify sites that were at the greatest risk Douglas-fir being overtopped by Scotch broom by first, identifying what sites generate the best Douglas-fir growth when they are young and at risk of being overtopped, and second, identifying site characteristics led to Scotch broom growing faster than Douglas-fir on sites they both occur on. To identify sites that produced greater young Douglas-fir height growth we used publicly available soil data from the Soil Survey Geographic Database and company management histories to predict tree heights measured through aerial laser scanning (LiDAR). We found that sites with soil textures that had higher percentages of smaller particles, were on lower elevations, and had gentler hillslopes could all produce greater Douglas-fir height growth. When attempting to identify what causes Douglas-fir to be at risk of being overtopped by Scotch broom we used plots with and without Scotch broom on a variety of field sites. This allowed us to not only identify which characteristics of sites where Douglas-fir was being outgrown by Scotch broom, but also identify if Scotch broom was changing how Douglas-fir grew. We found that reductions in Douglas-fir growth were related to Scotch broom being present and that increases in soil silt percentages, decreases in soil phosphorus concentrations, and increases in soil carbon percentages were related to Douglas-fir having height growth closer to or exceeding that of scotch broom.
946

Creation of a Site-Directed Mutant of Hen Egg White Lysozyme Working Toward Site-Specific Oxidation as it Relates to Protein Structure

Mensah, Eric 05 September 2009 (has links)
No description available.
947

Archaeomagnetic dating

Outram, Zoe, Harris, S., Batt, Catherine M. January 2014 (has links)
No / In May 2011, a team of archaeologists from the Department of Prehistory and Historical Archaeology of the University of Vienna, assisted by colleagues from the Czech Republic and Norway, carried out a research excavation at the Law Ting Holm in Tingwall on Shetland's Mainland. The site is believed to be the place of the main assembly of Shetland, which was in use most likely from the Norse period to the second half of the 16th century.
948

L'efficacité des sites web marchands destinés aux consommateurs culturellement divers : les effets de la congruence culturelle du site et de l'exposition répétée

Taieb, Besma 23 October 2012 (has links)
Cette thèse a pour objectifs d'étudier les réactions des groupes majoritaires et minoritaires face au site web marchand congruent à leur pays d'origine et au site web incongruent (site congruent au pays hôte/étranger), de mieux comprendre les effets de la congruence culturelle des sites marchands et d'évaluer les conditions d'efficacité du site culturellement incongruent. Nous avons élaboré un plan expérimental comportant trois variables à manipuler : la congruence culturelle du site web (faible versus forte), la fréquence d'exposition (1 exposition versus 2 expositions) et la population (minoritaire versus majoritaire). Deux sites web expérimentaux ont été conçus (le premier site est congruent à la population majoritaire et le second est congruent à la population minoritaire). Grâce à une analyse de contenu réalisée sur les sites locaux de la population minoritaire, nous avons identifié et sélectionné les marqueurs culturels dominants (tels que les couleurs, les polices, les images et les symboles) que nous avons manipulés pour concevoir les sites web expérimentaux. Les résultats obtenus montrent que le site culturellement congruent par rapport au site incongruent améliore l'attitude vis-à-vis du site, la confiance envers le site et l'intention de recommander. Toutefois, les effets positifs de la congruence culturelle du site web sur l'attitude et la confiance vis-à-vis du site sont plus forts pour la population majoritaire que pour la population minoritaire / This thesis aims to study the reactions of the majority and minority groups towards commercial website congruent with their country of origin and culturally incongruent website (site congruent with host country / abroad), to better understand the effects of commercial websites cultural congruity and to assess the conditions of culturally incongruent website effectiveness. We developed an experimental design with three variables to manipulate: website cultural congruity (low versus high), exposure frequency (1 exposure versus 2 exposures) and population (majority versus minority). Two experimental websites were designed (the first site is congruent with the majority population and the second is congruent with the minority population). Through a content analysis performed on the local sites of the minority population, we identified and selected the dominant cultural markers (such as colors, fonts, images and symbols) handled in designing experimental websites. The results show that culturally congruent site compared to incongruent site improves attitude, trust toward the site and intention to recommend. However, the positive effects of website cultural congruity on attitude and trust toward the site are stronger for the majority than the minority population. The results also indicate that repeated exposure to incongruent website improves attitude and trust toward the site, but it should be noted that repeated exposure has a stronger influence on attitude toward the incongruent site
949

Linear Enamel Hypoplasia At Santa Rita Corozal, Belize

Tetlow, Andrew Peter 01 January 2010 (has links)
The focus of this thesis is an analysis of a sample of dentition collected from the Postclassic Maya site of Santa Rita Corozal in Northern Belize. The goal of this study is to determine what the presence (or absence) of Linear Enamel Hypoplasia (LEH) can demonstrate about the general health (i.e. stress, disease, nutrition, and weaning age) and social status of a single subset of the Late Postclassic (900-1500 CE) Maya living at Santa Rita Corozal. Specifically, this thesis focuses on dentition of thirteen individuals from a large Postclassic platform group. The sample consists of sub-adult and adult female dentition from individuals that are associated with the same relative time period (Late Postclassic). The question being addressed in this thesis is: why has LEH presented in these individuals? These samples will also be compared to other studies involving LEH throughout the Maya area, in both similar and dissimilar environments. The preponderance of female and sub-adult remains also makes this platform group a very interesting topic of study for LEH in the Maya area, as it is unusual to find a concentrated area of individuals such as these. iv Importantly, the results of this study show that there is no significant relationship between general levels of stress and the overall status of an individual. Measurements collected from the LEH affected teeth demonstrate that all of the LEH episodes occurred before the age of 6. The mean age for the teeth sampled that show signs of LEH is 3.5 years, which is consistent with theories pertaining to the weaning age of the Maya during concomitant time periods. However, the size of this sample precludes any concrete conclusions about weaning ages and stress in general among the Maya at Santa Rita Corozal. It is also possible that these events are related to larger issues such as regional droughts or water-born disease.
950

KwaGandaganda : an archaeozoological case study of the exploitation of animal resources during the early Iron Age in KwaZulu-Natal

Beukes, Catharina F. 11 1900 (has links)
KwaGandaganda is an Early Iron Age (EIA) site in the .Mngeni valley (KwaZulu-Nata~ South Africa). Three cultural phases, Msuluzi, Ndondondwane and Ntshekane, dating between AD 620- AD 1030 were identified. The objective was to establish the extent of animal exploitation during the EIA in KwaZulu-Natal by means of faunal analysis, using internationally accepted methods. The collection included 41 006 fragments of which 22.9% were identifiable. A large number of species (68) were identified, including Rattus rattus. The collection yielded the largest quantity of ivory chips ever found on an EIA site in southern Africa, as well as an extensive variety of pathological specimens, mostly from Bos taurus. Several possible divining bones were present in the sample. Herd management, hunting strategies, gathering activities, fishing and trading of animal goods during the EIA were discussed, while the consequences of the unique excavation methods (i.e. the use of bulldozers) were also commented upon. / Anthropology and Archaeology / M.A. (Anthropology)

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