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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.
401

Bedarfsgerechte nachhaltige Entwicklung von Kleingartenanlagen in Sachsen: Studie im Auftrag des Landesverbandes Sachsen der Kleingärtner e.V.

May, Jens-Holger, Mühlpfordt, Anke, Haack, Julia 11 November 2019 (has links)
Das Sächsische Staatsministerium für Umwelt und Landwirtschaft (SMUL) und der Landesverband Sachsen der Kleingärtner (LSK) pflegen bereits seit vielen Jahren eine enge Zusammenarbeit. Dabei wird immer wieder auch über die künftige bedarfsgerechte und nachhaltige Kleingartenentwicklung im Freistaat unter den Bedingungen des demografischen Wandels und bei Berücksichtigung weiterer Einflussfaktoren beraten.
402

Wohnen bis ins Alter: Bauliche und organisatorische Voraussetzungen für lebenslanges Bewohnen von Baugemeinschaften

Widany, Anne-Kathrin 08 February 2011 (has links)
In der vorliegenden Arbeit wird der These nachgegangen, dass sich Baugemeinschaften als Wohnform, die von der Gemeinschaft und dem Zusammenleben geprägt ist, im Hinblick auf den demographischen Wandel und dessen Auswirkungen sich zum lebenslangen Bewohnen eignet. Untersucht wurden die baulichen und architektonischen, aber auch sozialen und organisatorischen Gegebenheiten am Beispiel 13 Dresdner Baugemeinschaften. Am Ende liegen Maßnahmen und Empfehlunen für künftige Bauherren und Planer vor. / The present study traces the hypothesis that joint building ventures as a form of living, that is affected by the community and the cohabit, in view of the demographic change and its effects, are suit to lifelong occupancy. To be proved are the structural and architectural, but also the social and organizational conditions using the example of 13 joint building ventures in Dresden. Finally there are measures and recommendations for future building owners and architects on hand.
403

SYNTHESIS AND EVALUATION OF LABELED PHOSPHATIDYLGLYCEROL PROBES TO ELUCIDATE MECHANISMS BEHIND CHOLESTEROL TRAFFICKING IN NIEMANN-PICK TYPE C DISEASE

Zachary J Struzik (12426840) 01 June 2022 (has links)
<p>  </p> <p>Niemann-Pick Type C (NPC) disease is a rare lysosomal storage disorder that occurs in about 1/89,000 to 1/120,000 live births and is characterized by an aberrant accumulation of cholesterol within the late endosome/lysosome of cells. Symptoms of this disease include splenomegaly, neurological deterioration, and often death before adulthood. Mutations in the membrane bound NPC1 or luminal NPC2 proteins lead to a decrease in cholesterol efflux within the lysosomes by which excess cholesterol crystallizes within membranes resulting in cell death. It has been demonstrated that increasing the amount of the lysosomal specific phospholipid Bis(monoacylglycerol)phosphate (BMP), also known as Lysobisphosphatidic acid (LBPA), in cells increases the rate of cholesterol transport in <em>npc1</em>-/- cells, but not in <em>npc</em>2-/- cells, indicating a strong synergistic relationship between the NPC2 protein and the lysosomal membranes. Increasing the amount of phosphatidyl glycerol (PG), a hypothesized precursor to BMP, has also shown an increase in cholesterol egress. While it is hypothesized that the increase in cholesterol clearance in the latter is due to the biosynthesis of LBPA from PG, there is no study to directly confirm this phenomenon. Therefore, we set out to synthesize diastereochemically pure PG containing isotopically labeled oleyl acyl chains to examine LBPA levels using lipidomic analysis of <em>npc1-/-</em> cells post treatment with PG. </p> <p>Initially, efforts centered around the use of phosphoramidite methodology commonly encountered in DNA oligonucleotide synthesis. While this route proved to be successful in making PG in modest yield (52%), reproducibility of this route with consistent yields was hindered due to the use of tetrabutylammonium fluoride (TBAF) in the final global deprotection step. Thus, we set out to discover a phosphorylated intermediate that did not require TBAF in the final step or contain easily hydrolysable protecting groups. It was discovered that H-phosphonate methodology using diphenyl phosphite for phosphorylation of the glycerol headgroup and backbone proved to be robust enough for PG synthesis. In this strategy, PG can be isolated in two steps from the final protected intermediate by first oxidizing the H-phosphonate from PIII to PV followed by deprotection of the glycerol head group under acidic conditions. Additionally, the H-phosphonate strategy also allowed us to omit headgroup modification prior to phosphorylation which reduced the number of synthetic steps from 11 steps to 7 steps. As a result, we were able to synthesize diastereochemically pure PG more consistently than the previous route in 75% yield. The route was further modified further to incorporate asymmetric acyl chains allowing the selective installation of a labeled acyl chain on the <em>sn</em>-1 or <em>sn</em>-2 positions of the phosphoglycerol backbone. The results from the lipidomic experiments indicate that increased LBPA concentrations in cells rise upon incubation with labeled PG. Additionally, increases in lyso-PG and acyl-PG are also observed leading to several hypotheses on how LBPA might be synthesized from PG. Future directions on this effort include identification of phospholipid species made from PG containing asymmetrically labeled acyl chains.  Synthesis of photoaffinity labeled PG is also underway to determine the protein partners involved in PG metabolism.</p>
404

Carolin Kosuch: Missratene Söhne. Anarchismus und Sprachkritik im Fin de Siècle

Gempp-Friedrich, Tilmann 23 July 2019 (has links)
No description available.
405

Architektur und Zionismus. Forschungsfelder, Wechselwirkungen, Wahrnehmung

Klei, Alexandra 21 August 2019 (has links)
No description available.
406

Die Militärakademie in Dresden (1959-1990): Ein Rückblick - aus Anlass ihrer Gründung vor 60 Jahren

Böhme, Rainer 10 December 2018 (has links)
Kurzdarstellung zur Geschichte der Gründung und Entwicklung der Militärakademie `Friedrich Engels`, Dresden, sowie deren Leistungsbilanz aus kritisch-wissenschaftlicher Sicht.:- Vorbemerkungen - zu Ergebnissen der historischen Forschung. - Zur Erinnerung. - Zur Militärakademie in der DDR-Hochschullandschaft. - Zur Vorgeschichte. - Zum Gründungsauftrag. - Zu den militärisch-politischen Rahmenbedingungen. - Zum militärakademischen vs. zivilen Studium. - Zum Lehrkörper. - Zum Promotionsrecht. - Zur Würdigung wissenschaftlicher Leistungen. - Zur strukturellen Organisation. - Zum militärakademischen Ausbildungsziel. - Zu den Absolventen der Militärakademie. - Zu den wissenschaftlichen Publikationen. - Zur wissenschaftlichen Kooperation. - Zum Umdenken über Krieg und Frieden im Nuklearzeitalter. - Zur Akademie zwischen Doktrin-87 und Militärreform 1990. - Zu den Auswirkungen des politischen Führungswechsels 1990. - Zum letzten Kapitel in der Geschichte der Militärakademie. - Schlussbemerkungen.
407

From Data to Decisions: Decisive Factors Influencing Swedish IT SMEs Adoption of Business Intelligence Systems

Nilfouroushan, Shayan, Almohtasib, Tarik January 2023 (has links)
Research Question: Which are the decisive factors that impact the adoption of business intelligence systems (BIS) among IT SMEs in Sweden? Purpose: This paper aims to examine Swedish SMEs and understand which decisive factors have an impact on the decision makers and their adoption of BIS. This study aims to study SMEs that have already adopted BIS. Method: A deductive qualitative approach was used to answer the study’s research question. The primary data was conducted through seven semi-structured interviews with Swedish IT SMEs. Empirical Findings: The empirical findings highlight that some factors had a greater influence on the adoption of BIS than others. These were possession of the right type of data, support of top management and service provider support. Conclusion: The presented study identified that small and medium sized enterprises are prone to BIS adoption when considering three decisive factors. First, the importance of possessing data and having the right type of data was a critical need and a factor for BIS adoption. Second, the use of service provider support for SMEs seemed to contribute with important value according to the findings. Third, working proactively with change management affected the perceived usefulness of technology and led to a higher chance of small and medium sized adopting BIS. / Frågeställning: Vilka är de avgörande faktorerna som påverkar antagande av business intelligence-system bland små och medelstora (SME) IT företag i Sverige? Syfte: Den här uppsatsen syftar på att undersöka svenska små och medelstora företag (SME) och förstå vilka faktorer som påverkar beslutsfattare och deras antagande av BIS. Uppsatsen syftar till att studera SME som redan har antagit BIS. Tillvägagångssätt: Denna studie använde en deduktiv kvalitativ metod för att besvara forskningsfrågan. Den primära datan samlades in genom sju semistrukturerade intervjuer med svenska SME inom IT-branschen. Bidrag: Resultaten visar att vissa faktorer hade ett större inflytande på antagande av BIS än andra. Dessa var innehav av rätt typ av data, stöd från högsta ledningen samt support från tjänsteleverantörer. Slutsats: Den presenterade studien identifierade att svenska SME är benägna att anta BIS när man överväger tre avgörande faktorer. För det första var vikten av att ha data och ha rätt typ av data ett kritiskt behov och en faktor för BIS antagande. För det andra verkade användningen av tjänsteleverantör stöd för små och medelstora företag bidra med ett viktigt värde enligt resultaten. För det tredje, att arbeta proaktivt med förändringsledning påverkade den upplevda användbarheten av teknik och ledde till en högre chans för SME att antagande BIS.
408

DESIGN AND SYNTHESIS OF POTENT HIV-1 PROTEASE INHIBITORS AND ENANTIOSELECTIVE SYNTHESIS OF ANTIDIABETIC AGENT, CARAMBOLAFLAVONE

William L. Robinson (12211523) 17 May 2024 (has links)
HIV-1 protease inhibitor drugs are important components of current antiretroviral therapy (cART). The cART treatment regimens dramatically improved life expectancy and mortality of patients with HIV-1 infection and AIDS. However, new and improved protease inhibitor drugs are essential for future treatment options. To this end, syntheses of optically active (3a<i>S</i>,4<i>S</i>,7a<i>R</i>)-hexahydro-4<i>H</i>-furo[2,3-<i>b</i>]pyran-4-ol, (3a<i>R</i>,4<i>R</i>,7a<i>S</i>)-hexahydro-4<i>H</i>-furo[2,3-b]pyran-4-ol, and (3<i>R</i>,3a<i>S</i>,6a<i>R</i>)-hexahydrofuro[2,3-6]furan-3-ol have been accomplished. These stereochemically defined heterocyclic derivatives are important high-affinity P2 ligands for a variety of highly potent HIV-1 protease inhibitors. The key steps for the synthesis hexehydrofuropyranol involve an efficient Paternò-Büchi [2+2] photocycloaddition, catalytic hydrogenation, acid-catalyzed cyclization to form the racemic ligand alcohol, and enzymatic resolution with immobilized Amano Lipase PS-30. Optically active ligand alcohols were obtained with high enantiomeric purity. Enantiomer (-)-ligand alcohol has been converted to potent HIV-1 protease inhibitors. <div><br></div><div>(3<i>R</i>,3a<i>S</i>,6a<i>R</i>)-Hexahydrofuro[2,3-<i>b</i>]furan-3-ol(<i>bis</i>-tetrahydrofuran) is a key subunit of darunavir, an FDA approved HIV-1 protease inhibitor drug which is widely used for the treatment of HIV/AIDS patients. This stereochemically defined bicyclic heterocycle is also embedded in a variety of highly potent HIV-1 protease inhibitors. The synthesis of optically active <i>bis</i>-tetrahydrofuran was achieved in optically pure form utilizing commercially available and inexpensive 1,2-<i>O</i>-isopropylidene-α-D-xylofuranose or 1,2-O-isopropylidene-α-D-glucofuranose as the starting material. The key steps involve a highly stereoselective substrate-controlled hydrogenation of ethyl 2-(dihydrofuran-3(2H)-ylidene)acetate, a Lewis acid-catalyzed anomeric reduction of a 1,2-<i>O</i>-isopropylidene-protected glycofuranoside, and a Baeyer-Villiger oxidation of a tetrahydrofuranyl-2-aldehyde derivative. Optically active (3<i>R</i>,3a<i>S</i>,6a<i>R</i>)-hexahydrofuro[2,3-<i>b</i>]furan-3-ol ligand was converted to darunavir efficiently. Furthermore, both furopyranol and bis-tetrahydrofuran ligand alcohols have been converted into a variety of potent HIV-1 protease inhibitors including inhibitors containing P2'-boronic acid ligands.<br></div><div><br></div><div>Diabetes mellitus is a chronic, progressive metabolic disorder that seriously threatens human health worldwide, particularly in developing countries. The prevalence of diabetes has been increasing steadily, especially in developing countries. Carambolaflavone A is a natural flavonoid isolated from the leaves of starfruit tree, <i>Averrhoacarambola</i>, in 2005. Carambolaflavone A possesses a <i>C</i>-aryl glycosidic linkage. Carambolaflavone A exhibited significant antihyperglycemic properties. More detailed biological studies reveal that it can lower acute blood glucose. The biology and chemistry of carambolaflavone A attracted our interest in synthesis and further design of interesting structural variants. A convergent total synthesis of carambolaflavone A has been accomplished. The synthesis highlights a bismuth triflate-catalyzed stereoselective C-aryl glycosylation of flavan and an appropriately protected D-fucose derivative as the key step. The glycosylation partners were synthesized from commercially available (±)-naringenin and D-(+)-galactose, respectively. An oxidative bromination and elimination reaction sequence was utilized to construct the flavone. The natural product is obtained in 10 steps (longest linear sequence) from D-(+)-galactose.<br></div>
409

Design and Synthesis of Gold (I) Acyclic Diamino Carbene Complexes as Metallodrugs for Cancer and for Asymmetric Catalysis

Asuramana Pedi Durayalage, Roshani 07 1900 (has links)
Many previous studies have demonstrated that gold compounds possess successful results in catalysis and in medicinal chemistry. The central aim of this dissertation is the design and synthesis of novel gold (I) acyclic diamino carbene complexes as a chemotherapeutic agent for triple-negative breast cancer (TNBC) and for catalysis. In this study, a series of chiral neutral and cationic gold (I) acyclic diamino carbene (ADC) complexes and neutral gold (I) bis- ADC complexes have been synthesized. As the chiral neutral gold (I) ADCs, four diastereomers of S binaphthyl L proline tertiary butyl ester gold (I) chloride, S binaphthyl D proline tertiary butyl ester gold (I) chloride, R binaphthyl L proline tertiary butyl ester gold (I) chloride, and R binaphthyl D proline tertiary butyl ester gold (I) chloride have been synthesized and characterized. Different chiral gold (I) ADC complexes with bulky chiral binaphthyl group and with different amine groups of morpholine, chiral proline methyl ester, and benzyl ester have been synthesized and characterized. After that four diastereomers of the nitrile adduct of cationic binaphthyl proline tertiary butyl ester nitrile and four diastereomers of the isonitrile versions of it have been synthesized and characterized. A series of gold (I) cationic bis ADC complexes have been synthesized and characterized. All these novel gold ADC complexes were tested for biological activity against TNBC cell line MDA-MB-231 and cationic S binaphthyl D proline ester isonitrile adduct, S binaphthyl D proline ester isonitrile adduct and R binaphthyl D proline ester isonitrile adduct gave promising inhibition rates. According to Lipinski's rule, lipophilicity determines the effectiveness of the drug absorption to the body through the lipid membrane. To determine the drug-likeness of the gold ADC complexes, log P values were calculated for some of the synthesized complexes using a modified shake flask method. Gold (I) ADC complexes have been renowned for their ability in catalysis, but enantioselective catalysis is not that well studied. A3 coupling reaction is a well-known reaction for the synthesis of propargyl amines. Here, A3 coupling reaction with a chiral amine has been performed using the previously synthesized four diastereomers of binaphthyl proline tertial butyl ester gold (I) ADCs (SL, RD, RL, SD) as the catalyst expecting four different diastereomers of the product. The reaction exhibited reasonable yields but with a low enantiomeric excess (ee%). However, it gave proof of the principle that asymmetric induction is possible with the synthesized novel chiral gold (I) ADC complexes.
410

Hydroxyamidinates et polymères de coordination : suspicions et valences mixtes

Leblanc, Mathieu 07 1900 (has links)
Dans un contexte où l’énergie représente un enjeu majeur pour les pays et organisations à économies émergentes et développées, la recherche de nouvelles sources renouvelables et la démocratisation des vecteurs énergétiques permettant l’approvisionnement mondial de façon durable constitue un devoir pour la communauté scientifique internationale. D’ailleurs, il serait essentiel que les nombreuses disciplines de la chimie concertent leurs efforts. Plus particulièrement, la croissance de la recherche en chimie de coordination orientée vers la photosynthèse artificielle ainsi que le développement de matériaux fonctionnels démontre l’importance indéniable de ce champ de recherche. Ce travail présente dans un premier temps l’étude des différentes voies de synthèse d’hydroxyamidines, un ligand chélatant aux propriétés de coordination prometteuses ne recevant que très peu d’attention de la part de la communauté scientifique. Dans un deuxième temps, nous présenterons le développement d’une stratégie d’assemblage de leurs complexes supramoléculaires impliquant des métaux de transition abondants et peu dispendieux de la première rangée. Dans un troisième temps, il sera question de l’investigation de leurs propriétés photophysiques et électrochimiques à des fins d’applications au sein de matériaux fonctionnels. Pour ce faire, les différentes voies de synthèse des hydroxyamidines et de leurs amidines correspondantes qui ont précédemment été étudiées par les membres du groupe seront tout d’abord perfectionnées, puis investiguées afin de déterminer leur versatilité. Ensuite, les propriétés de complexation des amox résultantes comportant des motifs sélectionnés seront déterminées pour enfin étudier les propriétés photophysiques et électrochimiques d’une série de complexes de métaux de transition de la première rangée. En somme, plusieurs designs qu’offrent les amox et bis-amox sont étudiés et les propriétés des architectures résultantes de leur auto-assemblage sont déterminées. / In a context where energy supply represents a major challenge for countries and organizations with emerging and developed economies, the search for new renewable resources and the democratization of energy vectors allowing sustainable worldwide supply is a responsibility for the international scientific community. Besides, it would be essential that the many disciplines of chemistry concerted their efforts. In particular, the growth of research in coordination chemistry oriented toward artificial photosynthesis and the development of functional materials demonstrates the undeniable importance of this field of research. The first part of the work presents different synthetic routes to hydroxyamidines, a chelating ligand with promising properties and receiving very little attention from the scientific community. Secondly, we present the development of a strategy of assembly of their supramolecular complexes involving abundant and cheap first row transition metal. Thirdly, we will discuss the investigation of their photophysical and electrochemical properties for their purposes in functional materials applications. To do this, the different synthesis routes of hydroxyamidines and their corresponding amidines which have previously been studied by other members of the group will first be improved then investigated to determine their versatility. Next, the complexing properties of the resulting amox having selected patterns will be determined to finally study the photophysical and electrochemical properties of a series of first row transition metal complexes. In sum, the various designs offered by amox and the bis-amox complexes are studied and the properties of the resulting architectures of their self-assemblies are determined.

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