Elizitierung von "hairy roots"-Kulturen des Edelweiß' mit abiotischen Faktoren

Im Jahr 2003 wurde aus den Wurzeln des Edelweiß ein neues Lignan, Leoligin, isoliert. Dieser Verbindung konnte bereits eine antiinflammatorische Aktivität nachgewiesen werden, außerdem könnte die Substanz in Zukunft zur Behandlung artheriosklerotischer Erkankungen eingesetzt werden. Auch in den "hairy roots" von Edelweiß ist diese Substanz enthalten. In der vorliegenden Arbeit sollte der Einfluss verschiedener abiotischer Elizitoren auf den Leoligingehalt untersucht werden. Dabei konnte die Synthese von Leoligin durch Zusatz von 6% Saccharose am stärksten stimuliert werdenIn 2003 a new lignan, leoligin, was isolated from the roots of Edelweiß. Anti-inflammatory properties of leoligin were reported and it might also repressent a novel lead for treatment of vein graft diseases. In hairy roots of Edelweiß leoligin can be detected too. In this work the influence of different abiotic elicitors on leoligin production were of interest. Elicitation with 6% sucrose resulted in the highest leoligin productio

“The Bard meets the Doctor” – Computergestützte Identifikation intertextueller Shakespearebezüge in der Science Fiction-Serie Dr. Who.

A single abstract from the DHd-2019 Book of Abstracts.Sofern eine editorische Arbeit an dieser Publikation stattgefunden hat, dann bestand diese aus der Eliminierung von Bindestrichen in Überschriften, die aufgrund fehlerhafter Silbentrennung entstanden sind, der Vereinheitlichung von Namen der Autor*innen in das Schema "Nachname, Vorname" und/oder der Trennung von Überschrift und Unterüberschrift durch die Setzung eines Punktes, sofern notwendig

GaAs/GaP quantum dots: Ensemble of direct and indirect heterostructures with room temperature optical emission

Producción CientíficaWe describe the optical emission and the carrier dynamics of an ensemble of self-assembled GaAs quantum dots embedded in GaP(001). The QD formation is driven by the 3.6% lattice mismatch between GaAs and GaP in the Stranski-Krastanow mode after deposition of more than 1.2 monolayers of GaAs. The quantum dots have an areal density between 6 and 7.6 × 1010 per cm−2 and multimodal size distribution. The luminescence spectra show two peaks in the range of 1.7 and 2.1 eV. The samples with larger quantum dots have red emission and show less thermal quenching compared with the samples with smaller QDs. The large QDs luminescence up to room temperature. We attribute the high energy emission to indirect carrier recombination in the thin quantum wells or small strained quantum dots, whereas the low energy red emission is due to the direct electron-hole recombination in the relaxed quantum dots.Comisión Europea (project FP7-ICT-2013-613024-GRASP

Cumulative impact assessment for ecosystem-based marine spatial planning

Claims for ocean space are growing while marine ecosystems suffer from centuries of insufficient care. Human pressures from runoff, atmospheric emissions, marine pollution, fishing, shipping, military operations and other activities wear on habitats and populations. Ecosystem-based marine spatial planning (MSP) has emerged worldwide as a strategic instrument for handling conflicting spatial claims among competing sectors and the environment. The twofold objective of both boosting the blue economy and protecting the environment is challenging in practice and marine planners need decision support. Cumulative Impact Assessment (CIA) was originally developed to provide an overview of the human imprint on the world\u27s ocean ecosystems. We have now added a scenario component to the CIA model and used it within Swedish ecosystem-based MSP. This has allowed us to project environmental impacts for different planning alternatives throughout the planning process, strengthening the integration of environmental considerations into strategic decision-making. Every MSP decision may entail a local shift of environmental impact, causing positive or negative consequences for ecosystem components. The results from Swedish MSP in the North Sea and Baltic Sea illustrate that MSP certainly has the potential to lower net cumulative environmental impact, both locally and across sea basins, as long as environmental values are rated high and prevailing pressures derive from activities that are part of MSP. By synthesizing innumerous data into comprehensible decision support that informs marine planners of the likely environmental consequences of different options, CIA enables ecosystem-based MSP in practice

Hinder och möjligheter för källsortering av humanurin

Seventy years ago, night soil from Göteborg, Sweden, was transported on barges up along the Göta River. Farmers in the surroundings of present Ale kommun used the night soil as a fertilizer. Now recirculation of plant nutrients from urban to rural areas is discussed again. This time the discussion is limited to recirculation of source separated human urine as a valuable fertilizer. Source separated human urine is an alternative to sewage treatment in sewage plants. In Sweden, a couple of pilot projects with human urine have already started, where house owners collect their urine, which is then used as a fertilizer by a farmer in the neighbourhood. Many local authorities are getting interested in this way of treating sewage. This study was made in Ale kommun, close to Göteborg, Sweden. Farmers, property managers and tenants were interviewed about their view of source separated human urine. The three groups interviewed were chosen because they represent the categories primarily involved in a future sewage system change. A qualitative method was used and the interviews were more like a conversation than strictly formal. Fourteen farmers, five property managers and ten tenants were interviewed. The farmers in Ale kommun in general have a positive attitude to using human urine in their production. They think that night soil from the urban areas must be returned to the fields in one way or another. They themselves would feel more satisfied by using human mine as a fertilizer than using the common manufactured fertilizers. The farmers have the knowledge about circulation of plant nutrients. But they are afraid of what unsuitable substances are poured into the toilets. An understanding between them and the tenants is required for a system with source separated human urine. The farmers' working situation, especially during spring, makes it hard for them to see how much of the manufactured fertilizers they would be able to replace by human urine. If it was made possible for them to hire labour, his would not be a problem. Nobody wants to drive into town and collect urine with their present equipment. Government regulations seem to be necessary. The fanners still believe that it would be easy to organize some separation of human urine, with one group responsible. Among the property managers there were both those who knew about the plant nutrition content in human urine and those who did not know about its worth at all. The most sceptical ones belonged to the smaller companies. The building sector seem to have gotten concerned about environmental questions only this year. A grass root-perspective is obvious, since they hardly want to act without interested tenants. The tenants think that source separated human urine would be more natural than the "rubbish" spread out on the fields today. They believe in recirculation. The usefulness of source separated human urine is not that obvious, though. It is not apparent for everyone why one talks about separating urine. There is a big need for knowledge about recirculation of plant nutrition

MBE-Wachstum und Charakterisierung von Germanium-Nanodrähten

Semiconductor nanowires, also called nanorods or nanowhiskers, are of particular interest for various applications in nanotechnology. Especially, germanium as a CMOS compatible material with its good electronic properties has gained renewed interest in recent years due to the availability of modern gate dielectrics. The present work deals with the vapor-liquid-solid growth of germanium nanowires and their characterization. The Growth has been carried out by means of molecular beam epitaxy using differently oriented germanium and silicon substrates whereas gold has been used to create metal catalyst droplets with radii of typically 100 nm and below. All stages from the substrate preparation to the final growth have been investigated in the frame of this work to find significant control parameters that influence the growth result. The droplet formation by means of gold evaporation onto the heated substrates has been investigated extensively on different substrates and for different surface preparations to identify parameters that are crucial for the resulting size distribution. Thereby sticking effects of the droplet circumference turned out to influence the radius distribution significantly. Germanium nanowires have been observed to grow preferentially along the crystallographic directions on all utilized substrate orientations leading to defined possible inclinations of the wires with respect to the substrate normal. In contrast to the faceting known from silicon wires, the sidewalls mainly exhibit four flat {111} facets whereas the tip is roof shaped consisting of another two {111} facets. Different models which describe the inclined growth are presented and discussed. Furthermore, the material transport during the growth has been investigated. The nanowire length was found to be up to eight times larger than the nominal layer thickness according to the total amount of deposited germanium which is explained by surface diffusion towards the nanowires. The diffusion dominated growth regime was confirmed by length-radius-plot showing a decrease of the nanowire length at increasing radii. A temperature dependent diffusion model has been utilized to describe the observed nanowire length as a function of the substrate temperature. Beside conventional nanowires, so-called in-plane nanowires which grow along the substrate surface have been studied. Like their vertically growing counterparts, they also tend to grow along in-plane directions which is particularly distinct on Ge(011) substrates. However, the fraction of nanowires which are aligned along is influenced by substrate imperfections which was intentionally affected by means of wet-chemical substrate preparation. In addition to the nanowire growth, techniques for selective catalyst removal as well as for nanowire embedding in an insulating, transparent matrix have been established which can be important prerequisites for further nanowire processing in terms of electric or optoelectronic applications.Halbleitende Nanodrähte, auch Nanosäulen oder Nanowhisker genannt, sind wegen vielfältiger Anwendungsmöglichkeiten auf dem Gebiet der Nanotechnologie von hohem Interesse. Das gilt insbesondere für Germanium mit seinen guten elektronischen Eigenschaften, welches in den letzten Jahren eine Renaissance erlebt hat. Ein wesentlicher Grund hierfür ist seine Verwendbarkeit in der CMOS Technologie durch die Entwicklung moderner Gate-Isolationsschichten. Die vorliegende Arbeit behandelt das Wachstum von Germanium Nanodrähten nach dem vapor-liquid-solid-Mechanismus (gasförmig-flüssig-fest) und deren Charakterisierung. Als metallisches Lösungsmittel zur Erzeugung von Tröpfchen mit Radien im Bereich von 100 nm und kleiner wurde Gold verwendet. Von der Substratpreparation bis zum Wachstum wurden alle Phasen der Herstellung von Nanodrähten untersucht, um die wesentlichen Parameter zu finden, welche wichtige Kenngrößen wie die Wachstumsrate oder den Radius der Nanostrukturen beeinflussen. Ein Schwerpunkt der Untersuchung ist die Bildung von Tröpfchen und deren Größenverteilung als Funktion der Temperatur auf verschiedenen Substraten sowie in Abhängigkeit von unterschiedlichen Oberflächenvorbehandlungen. Das Wachstum der Nanosäulen erfolgt auf allen verwendeten Substratorientierungen bevorzugt in den -Richtungen, was zu bestimmten Neigungswinkeln der Nanodrähte bezüglich der Substratnormalen führt. Anders als es von Silizium-Nanodrähten bekannt ist, weisen in -Richtung gewachsene Germaniumdrähte vier {111}-Seitenfacetten auf und eine dachförmige Spitze, die aus zwei weiteren {111}-Facetten besteht. Das bevorzugte Wachstum in -Richtungen wird anhand verschiedener Modelle diskutiert. Darüber hinaus wurde die Wachstumsrate der Nanowhisker unter Berücksichtigung des Stofftransportes untersucht. Es zeigt sich, dass die Oberflächendiffusion der Germaniumatome den entscheidenden Einfluss auf die Wachstumsrate der Nanodrähte hat. In einem entsprechenden Längen-Radius-Diagram ist ein diffusionslimitiertes Wachstumsregime ersichtlich. Die untersuchten Nanodrähte waren bis zu acht mal länger als die nominelle Schichtdicke, welche der Menge an deponiertem Germanium entspricht, was durch den diffusiven Stofftransport zum Wachstumsort an der Spitze der Nanodrähte erklärt werden kann. Die Wachstumsrate als Funktion der Temperatur konnte mit Hilfe der Temperaturabhängigkeit der Diffusionslänge im Rahmen eines einfachen Diffusionsmodels berechnet werden. Neben konventionellen Nanowhiskern wurden so genannte In-plane-Nanodrähte untersucht, welche innerhalb der Substratebene wachsen. Ähnlich wie vertikale Nanodrähte weisen diese bevorzugte, azimutale -Richtungen, was auf Ge(011) Substraten besonders ausgeprägt ist. Der Anteil an In-pane-Nanodrähten, welche entlang der bevorzugten Richtungen wachsen, ist abhängig von Defekten in der Substratoberfläche, wie zum Beispiel der Rauigkeit und konnte gezielt durch nasschemische Vorbehandlung beeinflusst werden. Diese Befunde können bei gerichtetem Wachstum von Nanodrähten entlang von Oberflächen von Bedeutung sein, was in der Literatur auch als Guided Growth bezeichnet wird. Zusätzlich zu Wachstumsuntersuchungen wurden Methoden getestet, um Goldtröpfchen nasschemisch bei möglichst geringem Ätzangriff von Germanium-Nanostrukturen zu entfernen. Darüber hinaus wurden Nanostrukturen mittels Spin-Coating in eine elektrisch isolierende und transparente Matrix eingebettet. Für zukünftige Anwendungen können beide Arbeitsschritte eine wichtige Rolle spielen