Refine
Has Fulltext
- no (168) (remove)
Year of publication
- 2017 (168) (remove)
Document Type
- Doctoral Thesis (168) (remove)
Is part of the Bibliography
- yes (168)
Keywords
- Politik (2)
- 3D geovirtual environment (1)
- 3D geovisualization system (1)
- 3D-Geovisualisierungssystem (1)
- 3D-geovirtuelle Umgebung (1)
- Atmosphärendynamik (1)
- Betriebswirtschaft (1)
- Bildende Kunst allgemein (1)
- Brand Equity (1)
- Brand Management (1)
- Bundeswehr (1)
- Business Development (1)
- Climate of Opinion (1)
- Durchflusszytometrie (1)
- Einstellung (1)
- Epidemiologie (1)
- Ernährungsmuster (1)
- European bats (1)
- Europäische Fledermausarten (1)
- Europäische Union (1)
- Finanzausgleich Deutschland (1)
- Finanzausgleich Schweiz (1)
- Finanzverfassung (1)
- GTPase (1)
- Gebietskörperschaft (1)
- German armed forces (1)
- Geschichte Europa (1)
- Grenzüberschreitende Kooperation (1)
- Haptene (1)
- Hitzewellen (1)
- Hostile-Media-Phenomenon (1)
- Hostile-Media-Phänomen (1)
- Hybridom (1)
- Immunfluoreszenz (1)
- Inklusion (1)
- Innovation Management (1)
- Innovationsmanagement (1)
- Jetstream (1)
- Klimawandel (1)
- Koordinierung (1)
- Künste (1)
- Landschaftsanalyse (1)
- Lastenausgleich (1)
- Lehramtsstudierende (1)
- Lehrkräfte (1)
- Markenführung (1)
- Markenwert (1)
- Marketing Strategy (1)
- Meeres-Governance (1)
- Meinungsklima (1)
- Naturschutz (1)
- Organisationsreform (1)
- Organisationstheorie (1)
- Pluralistic ignorance (1)
- Pluralistische Ignoranz (1)
- Product Scandals (1)
- Recht (1)
- Ressourcenausgleich (1)
- Rubisco (1)
- Selbstwirksamkeit (1)
- Serviceorientierte Architektur (SOA) (1)
- Spillover Effects (1)
- Standard (1)
- Strategisches Management (1)
- Telekonnektionen (1)
- Third-Person-Perception (1)
- Third-Person-Wahrnehmung (1)
- Typ-2-Diabetes mellitus (1)
- Unternehmensführung (1)
- agrammatic aphasia (1)
- agricultural production systems (1)
- agronomic factors (1)
- atmosphere dynamics (1)
- bifunctional enzyme (1)
- bildbasierte Repräsentation (1)
- bioenergy (1)
- biomass (1)
- biomass flows (1)
- biophysics (1)
- chloro-ribosome (1)
- climate change (1)
- conservation (1)
- conventional agriculture (1)
- coordination (1)
- cost compensation (1)
- energy efficiency (1)
- financial equalization in Germany (1)
- financial equalization in Switzerland (1)
- fiscal federalism (1)
- flow cytometry (1)
- fusion (1)
- galactolipids (1)
- hapten (1)
- heatwaves (1)
- hybridoma (1)
- image-based representation (1)
- immunofluorescence (1)
- inflectional morphology (1)
- jet stream (1)
- konventionelle Landwirtschaft (1)
- landscape analysis (1)
- language production (1)
- local and regional factors (1)
- marine governance (1)
- mechanobiology (1)
- mitochondrial transformation (1)
- monoclonal antibodies (1)
- monoklonale Antikörper (1)
- organization theory (1)
- organizational reform (1)
- photosynthesis (1)
- plastid transformation (1)
- primed picture naming (1)
- public organizations (1)
- regularity (1)
- resource equalization (1)
- ribosome assembly (1)
- service-oriented architecture (SOA) (1)
- standard (1)
- sulfadiazine (1)
- sustainability (1)
- systematischer Review (1)
- teleconnections (1)
- tissue engineering (1)
- tobacco (1)
- tobramycin (1)
- translation (1)
- Öffentliche Organisationen (1)
Institute
- Institut für Biochemie und Biologie (38)
- Öffentliches Recht (16)
- Institut für Ernährungswissenschaft (12)
- Institut für Physik und Astronomie (12)
- Sozialwissenschaften (11)
- Historisches Institut (10)
- Institut für Chemie (10)
- Wirtschaftswissenschaften (9)
- Institut für Geowissenschaften (7)
- Bürgerliches Recht (5)
"Wortabruf im Handumdrehen"?
(2017)
Shape change is a fundamental process occurring in biological tissues during embryonic development and regeneration of tissues and organs. This process is regulated by cells that are constrained within a complex environment of biochemical and physical cues. The spatial constraint due to geometry has a determining role on tissue mechanics and the spatial distribution of force patterns that, in turn, influences the organization of the tissue structure. An understanding of the underlying principles of tissue organization may have wide consequences for the understanding of healing processes and the development of organs and, as such, is of fundamental interest for the tissue engineering community.
This thesis aims to further our understanding of how the collective behaviour of cells is influenced by the 3D geometry of the environment. Previous research studying the role of geometry on tissue growth has mainly focused either on flat surfaces or on substrates where at least one of the principal curvatures is zero. In the present work, tissue growth from MC3T3-E1 pre-osteoblasts was investigated on surfaces of controlled mean curvature.
One key aspect of this thesis was the development of substrates of controlled mean curvature and their visualization in 3D. It was demonstrated that substrates of controlled mean curvature suitable for cell culture can be fabricated using liquid polymers and surface tension effects.
Using these substrates, it was shown that the mean surface curvature has a strong impact on the rate of tissue growth and on the organization of the tissue structure. It was thereby not only demonstrated that the amount of tissue produced (i.e. growth rates) by the cells depends on the mean curvature of the substrate but also that the tissue surface behaves like a viscous fluid with an equilibrium shape governed by the Laplace-Young-law. It was observed that more tissue was formed on highly concave surfaces compared to flat or convex surfaces.
Motivated by these observations, an analytical model was developed, where the rate of tissue growth is a function of the mean curvature, which could successfully describe the growth kinetics. This model was also able to reproduce the growth kinetics of previous experiments where tissues have been cultured in straight-sided prismatic pores.
A second part of this thesis focuses on the tissue structure, which influences the mechanical properties of the mature bone tissue. Since the extracellular matrix is produced by the cells, the cell orientation has a strong impact on the direction of the tissue fibres. In addition, it was recently shown that some cell types exhibit collective alignment similar to liquid crystals.
Based on this observation, a computational model of self-propelled active particles was developed to explore in an abstract manner how the collective behaviour of cells is influenced by 3D curvature. It was demonstrated that the 3D curvature has a strong impact on the self-organization of active particles and gives, therefore, first insights into the principles of self-organization of cells on curved surfaces.
Analyse der Funktion der dualen Lokalisation der 3-Mercaptopyruvat Sulfurtransferase im Menschen
(2017)
Rubisco catalyses the first step of CO2 assimilation into plant biomass. Despite its crucial role, it is notorious for its low catalytic rate and its tendency to fix O2 instead of CO2, giving rise to a toxic product that needs to be recycled in a process known as photorespiration. Since almost all our food supply relies on Rubisco, even small improvements in its specificity for CO2 could lead to an improvement of photosynthesis and ultimately, crop yield. In this work, we attempted to improve photosynthesis by decreasing photorespiration with an artificial CCM based on a fusion between Rubisco and a carbonic anhydrase (CA).
A preliminary set of plants contained fusions between one of two CAs, bCA1 and CAH3, and the N- or C-terminus of RbcL connected by a small flexible linker of 5 amino acids. Subsequently, further fusion proteins were created between RbcL C-terminus and bCA1/CAH3 with linkers of 14, 23, 32, and 41 amino acids. The transplastomic tobacco plants carrying fusions with bCA1 were able to grow autotrophically even with the shortest linkers, albeit at a low rate, and accumulated very low levels of the fusion protein. On the other hand, plants carrying fusions with CAH3 were autotrophic only with the longer linkers. The longest linker permitted nearly wild-type like growth of the plants carrying fusions with CAH3 and increased the levels of fusion protein, but also of smaller degradation products.
The fusion of catalytically inactive CAs to RbcL did not cause a different phenotype from the fusions with catalytically active CAs, suggesting that the selected CAs were not active in the fusion with RbcL or their activity did not have an effect on CO2 assimilation. However, fusions to RbcL did not abolish RbcL catalytic activity, as shown by the autotrophic growth, gas exchange and in vitro activity measurements. Furthermore, Rubisco carboxylation rate and specificity for CO2 was not altered in some of the fusion proteins, suggesting that despite the defect in RbcL folding or assembly caused by the fusions, the addition of 60-150 amino acids to RbcL does not affect its catalytic properties. On the contrary, most growth defects of the plants carrying RbcL-CA fusions are related to their reduced Rubisco content, likely caused by impaired RbcL folding or assembly. Finally, we found that fusions with RbcL C-terminus were better tolerated than with the N-terminus, and increasing the length of the linker relieved the growth impairment imposed by the fusion to RbcL. Together, the results of this work constitute considerable relevant findings for future Rubisco engineering.