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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.
181

Validitätsaspekte bei der Messung von Schreibkompetenzen

Canz, Thomas 21 October 2015 (has links)
Die Arbeit stellt eine nationale Bildungsstudie zur Erfassung von Schreibkompetenzen vor und untersucht das angewandte Verfahren auf drei ausgewählte Validitätsaspekte. In Studie I wird geprüft, ob es sich bei Schreibkompetenz sowie den Schreibkompetenzdimensionen Inhalt, Stil und sprachliche Richtigkeit um textmusterunabhängige oder textmusterspezifische Konstrukte handelt. Darüber hinaus wird die interne Struktur von Schreibkompetenz betrachtet. Die vorwiegend auf Modellvergleichen basierenden Analysen zeigen, dass es sich bei allgemeinen Schreibkompetenzen sowie bei inhaltlichen und stilistischen Schreibkompetenzen um textmusterspezifische Konstrukte handelt, bei der orthografisch-grammatischen Schreibkompetenz hingegen um ein textmusterunabhängiges Konstrukt. Für alle Textmuster zeigt sich eine zweidimensionale Struktur. In Studie II wird untersucht, inwiefern Lesefähigkeiten bei der Messung von Schreibkompetenzen aufgrund der textuellen Präsentation der Aufgabeninstruktion miterfasst werden. Der Einfluss der Lesekompetenz wird dabei als Zusammenhangsstärke zwischen Lese- und Schreibkompetenz in Abhängigkeit von leseschwierigkeitsquantifizierenden Merkmale via Mehrebenen¬moderatoranalysen geprüft. Es zeigen sich statistisch bedeutsame, aber praktisch kaum relevante Effekte für zwei der Merkmale: syntaktische Komplexität und Seltenheit der Wörter. In Studie III wird untersucht, ob eine von der sprachlichen Richtigkeit unabhängige Beurteilung inhaltlicher und stilistischer Schreibkompetenzen erfolgt oder ob Halo-Effekte zutage treten. In Anschlussanalysen wird geprüft, ob diese Halo-Effekte von Art und Anzahl der Fehler, Textlänge, Textkomplexität und Textmuster abhängen. Es zeigen sich keine Urteilsverzerrungen bei der inhaltlichen, jedoch bei der stilistischen Bewertung. Diese Verzerrungen sind größer bei syntaktisch komplexeren Texten und bei höherer Fehleranzahl, vor allem unter Vorliegen grammatischer Fehler und syntaktisch relevanter Zeichensetzungsfehler. / The dissertation presents a national educational study assessing writing competencies in German. The underlying process of measuring writing competencies is investigated regarding three selected aspects of validity. The first study addresses the question, whether writing competence as well as the writing competence dimensions, i.e. contentual, stylistic and orthographic-grammatic writing competencies are discourse mode dependent or independent constructs. Additionally the internal structure of writing competence is investigated. Analyses, predominantly based on comparison of IRT-models, reveal that general writing competencies as well as the contentual and stylistic dimensions are discourse-mode-specific constructs, whereas the orthographic-grammatic writing competence is discourse mode independent. The second study raises the question to what extent, due to the fact that the writing task instructions are given textually, reading competencies are included when measuring writing. Therefore two-level moderator analyses are computed, modelling the correlation between reading and writing competence dependent on reading difficulty quantifying aspects. Statistically significant but practically hardly relevant effects obtain for two of these aspects: syntactic complexity of the instruction text and (in)frequency of the used words. The third study investigates whether the evaluation of contentual and stylistic writing competencies takes place regardless of orthographic and grammatic features of the underlying texts or whether halo effects occur. Further analyses examine possible rating shifts in dependence of error types, error amount, text length, text complexity and discourse type. The results reveal that stylistic, but not contentual rating shifts occur. These shifts are more pronounced in regard to syntactically more complex texts as well as higher error quantities and arise particularly under the presence of grammatical and syntactically relevant punctuation errors.
182

Count on the brain

Dix, Annika 11 January 2016 (has links)
Wir können Mathematikleistungen über fluide Intelligenz (FI) vorhersagen. Der Einfluss von FI auf kognitive Prozesse und neuronale Mechanismen, die mathematischen Fähigkeiten in verschiedenen Teildisziplinen zugrunde liegen, ist jedoch wenig verstanden. Vorliegende Arbeit spezifiziert FI-bezogene Unterschiede in diesen Prozessen und Mechanismen beim Lösen von Geometrie-, Arithmetik- und Algebra-Aufgaben. Mithilfe eines multimethodalen Ansatzes beleuchtet sie das Zusammenspiel zwischen FI, Leistung und Faktoren wie Aufgabenkomplexität, Lernen und Strategiewahl, die kognitive Prozesse und Anforderungen beim Problemlösen beeinflussen. Leistungsunterschiede wurden durch Messung von Reaktionszeiten und Fehlerraten, Strategien durch Augenbewegungsanalyse erfasst. Als Indikator kortikaler Aktivität diente die ereigniskorrelierte (De-)Synchronisation (ERD/ERS) im Alpha-Band. Um kognitive Prozesse zu unterscheiden, haben wir die ERD/ERS im Theta-Band und den Alpha-Unterbändern einbezogen. Beim Lösen unvertrauter geometrischer Analogien zeichnete sich hohe FI durch verstärkte Verarbeitung visuell-räumlicher Informationen zum Repräsentieren von Merkmalszusammenhängen aus. Schüler mit hoher FI passten ihre Strategiewahl den Anforderungen flexibler an. Erstmals konnten wir durch trialweise Identifikation von Strategien FI-bezogene Unterschiede in der neuronalen Effizienz der Strategieausführung feststellen. Beim Lösen vertrauter arithmetischer und algebraischer Terme zeigten sich bei Schülern mit hoher im Vergleich zu Schülern mit durchschnittlicher FI geringere Anforderungen zur Aktualisierung numerischer Repräsentationen und eine bessere Leistung in komplexen Aufgaben. Weitere Analysen legen nahe, dass Schüler mit hoher FI Zusammenhänge in der Aufgabenstruktur besser erkennen und passende Routinen abrufen können. Die Fähigkeit Zusammenhangsrepräsentationen zu bilden könnte demnach ein Schlüsselaspekt zur Erklärung FI-abhängiger Unterschiede in mathematischen Fähigkeiten sein. / Fluid intelligence (FI) is a strong predictor of mathematical performance. However, the impact of FI on cognitive processes and neural mechanisms underlying differences in mathematical abilities across different subdivisions is not well understood. The present work specifies FI-related differences in these processes and mechanisms for students solving geometric, arithmetic, and algebraic problems. We chose a multi-methodological approach to shed light on the interplay between FI, performance, and factors such as task complexity, learning, and strategy selection that influence cognitive processes and task demands in problem-solving. We measured response times and error rates to evaluate performance, eye movements to identify solution strategies, and the event-related (de-)synchronization (ERD/ERS) in the broad alpha band as indicator of general cortical activity. Further, we considered the ERD/ERS in the theta band and the alpha sub-bands to distinguish between associated cognitive processes. For unfamiliar geometric analogy tasks, students with high FI built relational representations based on a more intense processing of spatial information. Strategy analyses revealed a more adaptive strategy choice in response to increasing task demands compared to students with average FI. Further, we conducted the first study identifying strategies and related cortical activity trial-wise and thereby identified FI-related differences in the neural efficiency of strategy execution. For solving familiar arithmetic and algebraic problems, high compared to average FI was associated with lower demands on the updating of numbers leading to a better performance in complex tasks. Further analyses suggest that students with high FI had an advantage to identify the relational structure of the problems and to retrieve routines that match this structure. Thus, the ability to build relational representations might be one key aspect explaining FI-related difference in mathematical abilities.
183

Differenzielle Validität von Mathematiktestaufgaben für Kinder mit nicht-deutscher Familiensprache

Haag, Nicole 18 December 2015 (has links)
Verschiedene Schulleistungsstudien stellten für Kinder mit nicht-deutscher Familiensprache bereits in der Grundschule substanzielle Disparitäten im Bereich Mathematik fest. Diese Disparitäten führten zu der Frage, ob die verwendeten Testverfahren zu hohe sprachliche Hürden für Kinder mit nicht-deutscher Familiensprache aufweisen und daher nicht ausreichend in der Lage sind, die Kompetenzen dieser Gruppe valide zu erfassen. In dieser kumulativen Arbeit wurde geprüft, inwiefern die sprachliche Komplexität von Mathematikaufgaben in der Grundschule einen benachteiligenden Einfluss auf die Erfassung der Mathematikleistung von Kindern mit nicht-deutscher Familiensprache darstellt. Zunächst wurde geprüft, ob die in nationalen Schulleistungsstudien verwendeten Aufgaben für diese Gruppe differenziell valide sind. Daran anschließend wurde untersucht, ob sich itemspezifische Kompetenznachteile durch die sprachlichen Merkmale der Aufgaben erklären lassen. In der vorliegenden Arbeit konnte gezeigt werden, dass die differenzielle Validität der betrachteten Testverfahren für Kinder mit nicht-deutscher Familiensprache insgesamt gering ausgeprägt ist. Ferner wurde festgestellt, dass sich die einzelnen sprachlichen Merkmale der Aufgaben sowohl spezifisch als auch gemeinsam auf die differenzielle Validität auswirken. Der größte Anteil der itemspezifischen Kompetenznachteile wurde durch mehrere Merkmale gemeinsam aufgeklärt. Eine experimentelle Teilstudie zeigte, dass eine sprachliche Vereinfachung nicht geeignet scheint, um die Kompetenznachteile von Kindern mit nicht-deutscher Familiensprache substanziell zu verringern. Ein Vergleich der Effekte sprachlicher Merkmale von Mathematikaufgaben auf die Mathematikleistungen von Kindern mit nicht-deutscher Familiensprache zwischen der dritten und der vierten Klassenstufe ergab, dass sich die sprachliche Komplexität der Aufgaben vor allem für jüngere Grundschulkinder unabhängig von ihrer Familiensprache benachteiligend auswirkte. / Large-scale assessment studies have repeatedly documented performance disadvantages of language minority students in German elementary schools. The substantial achievement gap has led to concerns regarding the validity of large-scale assessment items for language minority students. It may be the case that these performance differences are, in part, due to high language demands of the test items. These items may selectively disadvantage language minority students in the testing situation. This dissertation project investigated the connection between the academic language demands of mathematics test items and the test performance of monolingual students and language minority students. First, it was investigated whether the test items were differentially valid for language minority students. Moreover, the connection between the differential validity and the linguistic complexity of the test items was tested. The findings indicated that overall, differential validity of the examined tests for language minority students was low. However, the test items’ language demands were related to differential validity. The largest proportion of item-specific performance disadvantages was explained by confounded combinations of several linguistic features. Additionally, unique effects of descriptive, lexical, and grammatical features were identified. An experimental study showed that linguistic simplification did not seem to be a promising method to substantially reduce the performance differences between language minority students and German monolingual students. A comparison of differential effects of mathematics items’ language demands for language minority students over two adjacent grade levels indicated that the impact of academic language demands seemed to depend on grade level rather than on language minority student status. Regardless of their home language, younger students seemed to struggle more with linguistically complex test items than older students.
184

Psychophysiologische Parameter einer standardisierten Leistungssituation zum Verständnis des Bewältigungsverhaltens psychosomatischer Patientinnen

Gerhardt, Maren 27 April 2004 (has links)
Ergänzend zu bestehenden Verfahren Bewältigungsverhalten zu erfassen, versucht die vorliegende Studie mittels eines mehrdimensionalen Ansatzes neue Wege der psychosomatischen Grundlagenforschung zu eröffnen. Anhand des Biopsychologischen Belastungstests werden erlebens- (Annäherungsmotivation, Meidungsmotivation, Traitangst), verhaltens- und peripherpsychologische (Herzfrequenz, Hautleitwertreaktion) Parameter einer heterogenen Stichprobe aus gesunden Kontrollprobandinnen und psychosomatischen Patientinnen erhoben. Diese Parameter sollen eine Einteilung der Testpersonen in Untergruppen ermöglichen, um die Identifizierung von repressiv, optimistisch und konflikthaft bewältigenden Personen vornehmen zu können. In den Analysen lässt sich die Aufteilung der Untergruppen im hypothetisierten Rahmen allerdings nicht wiederfinden. Es zeigen sich signifikante Unterschiede zwischen den Motivationsebenen der Testpersonen (Annäherungsmotivation/Meidungsmotivation jeweils hoch/niedrig), sowie kontinuierlich signifikante Unterschiede zwischen den gesunden Kontrollprobandinnen und den psychosomatischen Patientinnen. Zusätzlich finden sich enge Parallelen zwischen Traitangst und Meidungsmotivation. / The following study proposes additionally to present methods a new multidimensional approach in psychosomatic research. Experience (approach motivation, avoidance motivation, trait-anxiety), behavioural, and peripher-psychological (heart frequency, skin conductance response) parameters are collected utilizing the Biopsychologischer Belastungstest (BBT). Using these parameters it is intended to separate test persons into clusters allowing the discrimination of coping patterns repression, optimism, and intra-personal approach avoidance conflict. The hypothesized subgroups can not be approved by the results of cluster analysis. However, significant differences between high and low approach respectively avoidance motivated test persons are found. Furthermore, throughout the analysis significant differences between "healthy" control persons and the psychosomatic patients are visible. In addition it can be emphasized that trait-anxiety is closely related to avoidance motivation.
185

Le complexe TFIIH dans la transcription effectuée par l'ARN polymèrase II et l'ARN polymèrase III / TFIIH complex in transcription mediated by RNA polymerase II and RNA polymerase III

Zadorin, Anton 28 September 2012 (has links)
Deux phénomènes liés au TFIIH ont été étudiés : l'influence des mutations spécifiques dans la sous-unité XPD de TFIIH sur la réponse transcriptionnelle de certains gènes après l'irradiation UV, et l'interaction entre le TFIIH et la transcription des gènes de classe III. Une analyse détaillée de la dynamique du transcriptome a été effectuée pour la réponse des cellules humaines mutantes XP-D/CS à l'UV. Il a été démontré que la dysrégulation sélective observée de l’expression des gènes était liée à l'incapacité pour la ré-initiation transcriptionnelle et à l'hétérochromatinisation suivante, où l'histonedésacétylase SIRT1 a été identifiée comme le principal facteur. Son inhibition a permis de recouvrer l'expression normale d'un nombre substantiel des gènes affectés. Une étude de la participation pangénomique du coeur de TFIIH dans latranscription a découvert son association avec les gènes actifs de classe III. Cette association a été démontrée être indépendante de Pol II. Le coeur de TFIIH a été montré participer directement à la transcription effectuée in vitro par Pol III. / In this work, two TFIIH-related phenomena were investigated : the influence of specific mutations in TFIIH XPD subunits on the transcriptional response of different genes on UV irradiation and the interaction between TFIIH and transcription of class III genes. For the first time the detailed investigation of transcriptome dynamics was carried out for the response of XP-D/CS mutant human cells to UV-irradiation. The transcription regulation nature of the observed selective gene expression dysregulation was clearly observed. Its relation to failure of transcription re-initiation and consequentheterochromatisation was demonstrated. SIRT1 histone deacetylase was identified as the main driver of the repressive chromatin establishment on the certain genes upon UV. Inhibition of SIRT1 was found to recover normal expression of substantial number of affected genes. SIRT1 mediated mechanism was shown to be XP-D/CS specific. A potential link between this longevity related protein and progeria features of XP-D/CS mutants was hypothesised. Genome-wide study of the involvement of the core TFIIH in transcription revealed its association with active class III genes, not described previously. This association was demonstrated to be Pol II-independent. The core TFIIH was shown to be directly involved in Pol III mediated transcription in vitro.
186

Fizičke karakteristike zemljišta i distribucija teških metala na gradskom području Novog Sada / Physical properties and the distribution of heavy metals in soils of the urban area of Novi Sad

Mihailović Aleksandra 25 August 2015 (has links)
<p>Uzorci zemlji&scaron;ta iz pov&scaron;inskog sloja dubine 0 - 10 cm<br />prikupljeni su sa 121 lokacije na gradskom području Novog<br />Sada. Ispitivano područje obuhvatilo je povr&scaron;inu (4 x 5)km<sup>2</sup>,<br />koja je podeljena na mrežna polja veličine (400 x 400) m<sup>2&nbsp;</sup>i u&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br />svakom polju uzet je po jedan uzorak. Za 121 uzorak<br />gradskog zemlji&scaron;ta Novog Sada ispitana su fizičko-hemijska<br />svojstva zemlji&scaron;ta, ukupni i pristupačni sadržaj metala (As,<br />Co, Cr, Cu, Mn, Ni, Pb, Zn) i njihova prostorna raspodela.<br />Konturne mape prostorne raspodele metala u zemlji&scaron;tu<br />dobijene su kori&scaron;ćenjem interpolacijske metode običnog<br />kriginga. Za pojedine uzorke izvr&scaron;eno je razdvajanje čestica<br />po veličinama frakcionisanjem u vodi pomoću sita različitih<br />veličina i identifikovani su minerali prisutni u frakciji prah +<br />glina. Aktivnosti radionuklida &bdquo;unsupported&rdquo;<sup> 210</sup>Pb i <sup>137</sup>Cs<br />određene su za jedan deo uzoraka zemlji&scaron;ta u Novom Sadu i<br />za uzorke zemlji&scaron;ta pored fabrike akumulatora u Somboru.<br />Ispitana je i vertikalna distribucija stabilnog i radioaktivnog<br />Pb u zemlji&scaron;tu.</p><p>Na 14 lokacija u Novom Sadu prikupljeno je 35 uzoraka<br />snega direktno sa asfaltnih puteva i sa zemljanih povr&scaron;ina u<br />okolini puteva i na pe&scaron;ačkim ostrvima. Raspodela čestica po<br />veličinama i ukupne koncentracije metala (Al, Ca, Cu, Fe, K,<br />Na, Mn, Ni, Pb, Zn) određene su analizom filtriranih uzoraka,<br />a za 4 uzorka ispitana je morfologija čestica i urađena<br />semikvantitativna analiza čestica u suvoj materiji.</p><p>Prilikom obrade rezultata merenja primenjene su metode<br />deskriptivne statistike i multivarijacione statističke analize u<br />cilju identifikacije izvora zagađenja i određivanja povezanosti<br />između samih metala i drugih parametara.</p> / <p>A total of 121 surface soil samples were collected&nbsp;across the central part of Novi Sad covering a surface&nbsp;area (4 km x 5 km). The physicochemical properties,&nbsp;pseudo total and available metal concentrations (As,&nbsp;Co, Cr, Cu,&nbsp; Mn, Ni, Pb, and Zn) were determined.&nbsp;Contour maps of spatial distribution of the investigated&nbsp;metals were obtained using ordinary&nbsp; kriging&nbsp;interpolation method. Separation of different particle&nbsp;<br />size fractions by wet sieving&nbsp; and identification of&nbsp;minerals in the clay and silt fraction for some soil&nbsp;samples were performed.&nbsp; Specific activities of&nbsp;radionuclides &ldquo;unsupported&rdquo; <sup>210</sup>Pb and <sup>137</sup>Cs were&nbsp;measured in forty soil samples collected in urban area&nbsp;of Novi Sad and industrial area of Sombor (near a&nbsp;battery manufacturer).&nbsp; Vertical distribution of stable and&nbsp;radioactive&nbsp; Pb for&nbsp; two samples from the industrial soil&nbsp;was examined.</p><p>Thirty five snow samples were collected at fourteen&nbsp;locations near crossroads in Novi Sad. The samples&nbsp;were taken directly from the road surface and from the&nbsp;ground surface in the vicinity of roads and on&nbsp;pedestrian islands. Particle size distribution and &nbsp;total&nbsp;concentration of the metals (Al, Ca, Cu, Fe, K, Na, Mn,&nbsp;Ni, Pb, Zn) were &nbsp;determined for filtered samples. Semi-quantitative analysis of the particles was &nbsp;conducted and&nbsp;morphology of the particles was examined for dry&nbsp;matter of four snow samples.&nbsp;</p><p>Methods of descriptive and multivariate statistics and&nbsp;geostatistics were carried out for &nbsp;the analysis and&nbsp;interpretation of the data.</p>
187

Implementation and assessment of bi-radionuclide seeds for permanent implant prostate brachytherapy

Nuttens, Vincent E 20 March 2008 (has links)
Interstitial brachytherapy using permanent seeds is a common modality for the treatment of early stage prostate cancer. It consists of inserting hundreds of radioactive seeds (size of a grain of rice) in the prostate by means of transperineal needles. In this procedure, dose delivery to healthy surrounding organs at risk (OAR) and dose homogeneity within the prostate are of prime concern. Placement errors should therefore be minimized to avoid unacceptable area underdosage or overdosage. At present, brachytherapy seeds can be loaded with three different radionuclides: iodine-125 (<sup>125</sup>I: 28.37 keV; 59.40 days), palladium-103 (<sup>103</sup>Pd: 20.74 keV; 16.991 days), and cesium-131 (<sup>131</sup>Cs: 30.45 keV; 9.689 days). Long or short term morbidity is the main drawback of <sup>125</sup>I and <sup>131</sup>Cs due to their deeper penetration in the normal tissues. However, both provide a good homogeneity of the dose distribution within the prostate. By contrast, <sup>103</sup>Pd offers a short penetration depth that reduces the dose to OAR. Nevertheless, it could result in cold spot (underdosage) where a recurrence of the cancer could appear. A compromise had to be found between good implant uniformity and low dose to OAR. We propose therefore to study if the combination of two radionuclides inside the same seed could be a solution. Two mixtures were considered: <sup>103</sup>Pd<sub>0.75</sub>-<sup>125</sup>I<sub>0.25</sub> and <sup>103</sup>Pd<sub>0.25</sub>-<sup>131</sup>Cs<sub>0.75</sub>. The subscripts denote the fractions of internal activity of each radionuclide. The work is subdivided into three steps. First we adapt the AAPM TG-43U1 dosimetry formalism used by the physician to make multiple-radionuclides sources compatible with Treatment Planning Systems (TPS). Then the dose distributions around the bi-radionuclide seeds are determined. Second, the prescription doses for both sources are derived using the linear quadratic model for tumor cell surviving fraction. They were computed using mono-radionuclide implants as benchmarks. Finally, treatment plans and Dose-Volume Histograms parameters have been computed on real patients virtually implanted with bi-radionuclide seeds and the results were compared with the mono-radionuclide one. These parameters can then be used to evaluate the Normal Tissue Complication Probability (NTCP) of urethra, the most exposed organ at risk in prostate brachytherapy. First, dosimetry results show that, from a pure physical point of view (i.e. without tissue reponse), the dose distributions of both mixtures lies in between that for <sup>103</sup>Pd and <sup>125</sup>I/<sup>131</sup>Cs. The compromise between homogeneity and reduced dose at large distance can be reached. Second, the averaged prescription doses for the Pd-I mixture are 142<sup>+15</sup><sub>-16</sub>Gy and 142<sup>+6</sup><sub>-8</sub>Gy using <sup>103</sup>Pd and <sup>125</sup>I as benchmarks, respectively. The values for the Pd Cs mixture are 128<sup>+13</sup><sub>-13</sub>Gy and 115<sup>+6</sup><sub>-7</sub>Gy, using <sup>103</sup>Pd and <sup>131</sup>Cs, respectively, as benchmarks. Finally, urethral NTCP results fall in the 19 to 23% range. However, they are affected by large uncertainties, making the comparison difficult. At present, no conclusion could be drawn about the efficiency of bi-radionuclide brachytherapy in comparison with mono-radionuclide using the available models. Permanent seed prostate brachytherapy suffers a lot from the lack of precision on radiobiological modelling parameters. A better knowledge of their values could significantly improve the predicting models and therefore lead to better treatment outcome.
188

Flexibility – a tool for chirality control in asymmetric catalysis

Zalubovskis, Raivis January 2006 (has links)
This thesis deals with the design and synthesis of ligands for asymmetric catalysis: palladium catalyzed allylic alkylations, and rho-dium and iridium catalyzed hydrogenations of olefins. Chirally flexible phosphepine ligands based on biphenyl were synthesized and their properties were studied. The rotation barrier for configurationally flexible phosphepines was determined by NMR spectroscopy. The ratio of the atropisomers was shown to depend on the group bound to phosphorus. Only complexes with two homochiral ligands bound to the metal center were observed upon complexation with Rh(I). It was shown that one diastereomer of the flexible ligand exhibits higher activity but lower selectivity than its diastereomer in the rhodium catalyzed hydrogenation of methyl alfa-acetamidocinnamate. These ligands were also tested in nickel catalyzed silabora-tions. Chiral P,N-ligands with pseudo-C2 and pseudo-CS symmetry based on pyrrolidines-phospholanes or azepines-phosphepines were synthesized and studied in palladium catalyzed allylic alkylations. Semi-flexible azepine-phosphepine based ligands were prepared and their ability to adopt pseudo-C2 or pseudo-CS symmetry depending on the substrate in allylic alkylations was studied. It was shown on model allyl systems with flexible N,N-ligands that the ligand prefers CS-symmetry in compexes with anti-anti as well as syn-syn allyl moieties, but that for the latter type of complexes, according to computations, the configuration of the ligand is R*,R* in the olefin complexes formed after addition of a nucleophile to the allylic group. A preliminary investigation of the possibilities to use a su-pramolecular approach for the preparation of P,N-ligands with pseudo-C2 and pseudo-S symmetry was made. An N,N-ligand with C2 symmetry was prepared and its activity in palladium catalyzed ally-lic alkylation was studied. Pyridine-based P,N-ligands were tested in iridium catalyzed hy-drogenations of unfunctionalized olefins with good activities and se-lectivities. In order to attempt to improve the selectivity, ligands with a chirally flexible phosphepine fragment were prepared and applied in catalysis with promising results. / QC 20100929
189

Foreign Market Analysis : Should Oriflame Enter France?

Tunbjer, Michael, Jarne, Marion January 2006 (has links)
The global marketplace today encompasses 6 billion people. Many companies are beginning to see themselves as international rather than national acting on a global arena. An essential aspect of going abroad is to know where to go and why to go there. In order to be able to analyze a foreign market a company needs to do market research in the foreign market as to gather essential information. A firm which is facing a quick internationalization process is the Swedish direct sales firm of cosmetics Oriflame. Oriflame has grown quickly in developing countries but is not present in one of the biggest market for direct sales in Europe: France. The purpose of this thesis is to develop a theoretical framework to analyze foreign markets and apply it to the French market of direct sales in cosmetics and Oriflame. A qualitative study based on the 5 Cs framework for analyzing foreign markets has been carried out. Seven focus groups have been conducted in France and Sweden in order to obtain information about and comparability in consumer attitudes towards Oriflame’s marketing mix. Interviews have been conducted in order to get information about Oriflame as a company. Secondary data has been gathered from different sources for the theoretical framework as well as for the empirical research on issues such as culture, competition and market. This thesis has developed a theoretical framework to analyze foreign markets called the 5 Cs. The 5 Cs are based on: Company, Constitution, Competition, Customers and Culture. The 5 Cs is a very general framework and can be applied to a wide range of foreign markets and firms and was in this case applied to analyze a real world case of Oriflame and France. The analysis of the empirical findings found that there is potential for Oriflame to enter the French market in terms of consumer preferences and general market characteristics. However, it also found that what will probably determine everything in the end is whether Oriflame can be strategically committed to enter a mature West European market like France.
190

Foreign Market Analysis : Should Oriflame Enter France?

Tunbjer, Michael, Jarne, Marion January 2006 (has links)
<p>The global marketplace today encompasses 6 billion people. Many companies are beginning to see themselves as international rather than national acting on a global arena. An essential aspect of going abroad is to know where to go and why to go there. In order to be able to analyze a foreign market a company needs to do market research in the foreign market as to gather essential information. A firm which is facing a quick internationalization process is the Swedish direct sales firm of cosmetics Oriflame. Oriflame has grown quickly in developing countries but is not present in one of the biggest market for direct sales in Europe: France.</p><p>The purpose of this thesis is to develop a theoretical framework to analyze foreign markets and apply it to the French market of direct sales in cosmetics and Oriflame.</p><p>A qualitative study based on the 5 Cs framework for analyzing foreign markets has been carried out. Seven focus groups have been conducted in France and Sweden in order to obtain information about and comparability in consumer attitudes towards Oriflame’s marketing mix. Interviews have been conducted in order to get information about Oriflame as a company. Secondary data has been gathered from different sources for the theoretical framework as well as for the empirical research on issues such as culture, competition and market.</p><p>This thesis has developed a theoretical framework to analyze foreign markets called the 5 Cs. The 5 Cs are based on: Company, Constitution, Competition, Customers and Culture. The 5 Cs is a very general framework and can be applied to a wide range of foreign markets and firms and was in this case applied to analyze a real world case of Oriflame and France. The analysis of the empirical findings found that there is potential for Oriflame to enter the French market in terms of consumer preferences and general market characteristics. However, it also found that what will probably determine everything in the end is whether Oriflame can be strategically committed to enter a mature West European market like France.</p>

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