Investigation of useful traits in breeding of Melissa officinalis L.

Diese Arbeit stellt die grundlegenden Ergebnisse des Projektes „Entwicklung generativ vermehrbarer Hochleistungslinien von Zitronenmelisse (Melissa officinalis) durch konventionelle Erzeugung homozygoter Linien als Voraussetzung für Synthetiks oder Hybridsorten“ dar, welches im Rahmen des Demonstrationsprojektes „Verbesserung der internationalen Wettbewerbsposition des deutschen Arznei- und Gewürzpflanzenanbaus am Beispiel der züchterischen und anbautechnologischen Optimierung von Kamille, Baldrian und Zitronenmelisse“ durch die FNR gefördert wurde vor. Ziel dieser Arbeit ist es im Konkreten das Grundwissen über die Gattung Melissa bereitzustellen und im Allgemeinen Grundlagen für neue Züchtungsmethoden in der Familie der Lamiaceae und anderen Arznei- und Gewürzpflanzen zu schaffen und durch den Züchtungsfortschritt den Anbau von Arznei- und Gewürzpflanzen zu unterstützen. In Form einer kumulativen Disseration werden die veröffentlichten Ergebnisse der Untersuchungen der Genpools der uns zur Verfügung gestellten Akzessionen zusammenfassend dargestellt. Die Veröffentlichungen „Chromosome number and ploidy level of balm (Melissa officinalis)”, „Evaluation of 28 balm and lemon balm (Melissa officinalis) accessions for content and composition of essential oil and content of rosmarinic acid” und „Content and composition of essential oil and content of rosmarinic acid in lemon balm and balm genotypes (Melissa officinalis)” befassen sich mit der Untersuchung der züchterischen Grundlagen an Melisse. In den Arbeiten werden die grundlegenden Eigenschaften der Akzessionen und Genotypen wie Ploidiestatus, Gehalt und Zusammensetzung des ätherischen Öles und der Gehalt an Rosmarinsäure beschrieben. Besonders hervorzuheben ist dabei die Erstbeschreibung triploider Melissegenotypen sowie der drei beschriebenen Chemotypen der Melisse. Diese Arbeit enthält somit wichtige und wertvolle Informationen zur Kulturpflanze Melisse und darüber hinaus Ansatzpunkte für moderne Züchtungsverfahren in Arznei- und Gewürzpflanzen der Familie Lamiaceae.This thesis contains the published results of the ”Development of generative propagatable high yielding lines of lemon balm (Melissa officinalis L.) via conventional generating of homozygote lines as a prereqisite for synthetic and hybrid variaties” (original title in German: „Entwicklung generativ vermehrbarer Hochleistungslinien von Zitronenmelisse (Melissa officinalis L.) durch konventionelle Erzeugung homozygoter Linien als Voraussetzung für Synthetiks oder Hybridsorten“) which was part of the project “Improving the international position of the German production of medical herbs and spices, by taking the example of the optimisation of breeding and cultivation of valerian, camomile and lemon balm.“ and was funded by the Fachagentur für Nachwachsende Rohstoffe . The papers “Chromosome number and ploidy level of balm (Melissa officinalis)”, “Evaluation of 28 balm and lemon balm (Melissa officinalis) accessions for content and composition of essential oil and content of rosmarinic acid” and “Content and composition of essential oil and content of rosmarinic acid in lemon balm and balm genotypes (Melissa officinalis)” contain important results for modern breeding attempts in lemon balm. The publications show the characteristics of the accessions and genotypes such as ploidy status, content and composition of essential oil and content of rosmarinic acid. Of particular importance are the first descriptions of triploid Melissa genotypes, as well as three Melissa chemotypes, which have never been outlined before

Strategien für die Melissezüchtung (Melissa officinalis)

Es wurden 120 Melisseherkünfte in Feldversuchen evaluiert. In diesem Material wurde die Variabilität für Winterhärte, Gehalt und Zsammensetzung des ätherischen Öls, Rosmarinsäuregehalt und eingeschränkt Blattertrag beschrieben. Die beschriebene Variabilität ermöglichte die Entwicklung homozygoter Linien mit hoher Eigenleistung für die genannten Zuchtziele bis zur I4-Inzuchtgeneration. Die Kreuzung definierter Linien ermöglichte die Schaffung eines neuen Genpools als Ausgansmaterial für die Entwicklung weiterer aussichtsreicher Linien. Stichwörter: Melisse, Melissa officinalis L., Winterhärte, ätherisches Öl, Rosmarinsäure, ZüchtungBreeding strategies for lemon balm (Melissa officinalis)Evaluation was carried out in field experiments with 120 accessions of lemon balm. This material was characterized for winter hardiness, amount and composition of essential oil, amount of rosmarinic acid and, to a certain degree, for yield of leaves. The characterized variability opened the possibility to develop homozygous lines for the mentioned breeding goals up to inbreed generation I4. Crossing of defined lines created a new gene pool of basic material for development of new promising lines. Keywords: lemon balm, Melissa officinalis L., winter hardiness, essential oil, rosmarinic acid, breedin

A multi-center study of their physicochemical characteristics, cell culture and in vivo experiments

PVP-capped silver nanoparticles with a diameter of the metallic core of 70 nm, a hydrodynamic diameter of 120 nm and a zeta potential of −20 mV were prepared and investigated with regard to their biological activity. This review summarizes the physicochemical properties (dissolution, protein adsorption, dispersability) of these nanoparticles and the cellular consequences of the exposure of a broad range of biological test systems to this defined type of silver nanoparticles. Silver nanoparticles dissolve in water in the presence of oxygen. In addition, in biological media (i.e., in the presence of proteins) the surface of silver nanoparticles is rapidly coated by a protein corona that influences their physicochemical and biological properties including cellular uptake. Silver nanoparticles are taken up by cell-type specific endocytosis pathways as demonstrated for hMSC, primary T-cells, primary monocytes, and astrocytes. A visualization of particles inside cells is possible by X-ray microscopy, fluorescence microscopy, and combined FIB/SEM analysis. By staining organelles, their localization inside the cell can be additionally determined. While primary brain astrocytes are shown to be fairly tolerant toward silver nanoparticles, silver nanoparticles induce the formation of DNA double-strand-breaks (DSB) and lead to chromosomal aberrations and sister-chromatid exchanges in Chinese hamster fibroblast cell lines (CHO9, K1, V79B). An exposure of rats to silver nanoparticles in vivo induced a moderate pulmonary toxicity, however, only at rather high concentrations. The same was found in precision-cut lung slices of rats in which silver nanoparticles remained mainly at the tissue surface. In a human 3D triple-cell culture model consisting of three cell types (alveolar epithelial cells, macrophages, and dendritic cells), adverse effects were also only found at high silver concentrations. The silver ions that are released from silver nanoparticles may be harmful to skin with disrupted barrier (e.g., wounds) and induce oxidative stress in skin cells (HaCaT). In conclusion, the data obtained on the effects of this well-defined type of silver nanoparticles on various biological systems clearly demonstrate that cell-type specific properties as well as experimental conditions determine the biocompatibility of and the cellular responses to an exposure with silver nanoparticles

Micro-spectroscopy on silicon wafers and solar cells

Micro-Raman (μRS) and micro-photoluminescence spectroscopy (μPLS) are demonstrated as valuable characterization techniques for fundamental research on silicon as well as for technological issues in the photovoltaic production. We measure the quantitative carrier recombination lifetime and the doping density with submicron resolution by μPLS and μRS. μPLS utilizes the carrier diffusion from a point excitation source and μRS the hole density-dependent Fano resonances of the first order Raman peak. This is demonstrated on micro defects in multicrystalline silicon. In comparison with the stress measurement by μRS, these measurements reveal the influence of stress on the recombination activity of metal precipitates. This can be attributed to the strong stress dependence of the carrier mobility (piezoresistance) of silicon. With the aim of evaluating technological process steps, Fano resonances in μRS measurements are analyzed for the determination of the doping density and the carrier lifetime in selective emitters, laser fired doping structures, and back surface fields, while μPLS can show the micron-sized damage induced by the respective processes

Finding the Needles in the Metagenome Haystack

In the collective genomes (the metagenome) of the microorganisms inhabiting the Earth’s diverse environments is written the history of life on this planet. New molecular tools developed and used for the past 15 years by microbial ecologists are facilitating the extraction, cloning, screening, and sequencing of these genomes. This approach allows microbial ecologists to access and study the full range of microbial diversity, regardless of our ability to culture organisms, and provides an unprecedented access to the breadth of natural products that these genomes encode. However, there is no way that the mere collection of sequences, no matter how expansive, can provide full coverage of the complex world of microbial metagenomes within the foreseeable future. Furthermore, although it is possible to fish out highly informative and useful genes from the sea of gene diversity in the environment, this can be a highly tedious and inefficient procedure. Microbial ecologists must be clever in their pursuit of ecologically relevant, valuable, and niche-defining genomic information within the vast haystack of microbial diversity. In this report, we seek to describe advances and prospects that will help microbial ecologists glean more knowledge from investigations into metagenomes. These include technological advances in sequencing and cloning methodologies, as well as improvements in annotation and comparative sequence analysis. More significant, however, will be ways to focus in on various subsets of the metagenome that may be of particular relevance, either by limiting the target community under study or improving the focus or speed of screening procedures. Lastly, given the cost and infrastructure necessary for large metagenome projects, and the almost inexhaustible amount of data they can produce, trends toward broader use of metagenome data across the research community coupled with the needed investment in bioinformatics infrastructure devoted to metagenomics will no doubt further increase the value of metagenomic studies in various environments

Searching for eV-scale sterile neutrinos with eight years of atmospheric neutrinos at the IceCube neutrino telescope

We report in detail on searches for eV-scale sterile neutrinos, in the context of a 3+1 model, using eight years of data from the IceCube neutrino telescope. By analyzing the reconstructed energies and zenith angles of 305,735 atmospheric $\nu_\mu$ and $\bar{\nu}_\mu$ events we construct confidence intervals in two analysis spaces: $\sin^2 (2\theta_{24})$ vs. $\Delta m^2_{41}$ under the conservative assumption $\theta_{34}=0$; and $\sin^2(2\theta_{24})$ vs. $\sin^2 (2\theta_{34})$ given sufficiently large $\Delta m^2_{41}$ that fast oscillation features are unresolvable. Detailed discussions of the event selection, systematic uncertainties, and fitting procedures are presented. No strong evidence for sterile neutrinos is found, and the best-fit likelihood is consistent with the no sterile neutrino hypothesis with a p-value of 8\% in the first analysis space and 19\% in the second.Comment: This long-form paper is a companion to the letter "An eV-scale sterile neutrino search using eight years of atmospheric muon neutrino data from the IceCube Neutrino Observatory". v2: update other experiments contours on results plo

Simulation of SVPWM Based Multivariable Control Method for a DFIG Wind Energy System

This paper deals with a variable speed device toproduce electrical energy on a power network based on adoubly-fed induction machine used in generating mode(DFIG) in wind energy system by using SVPWM powertransfer matrix. This paper presents a modeling and controlapproach which uses instantaneous real and reactive powerinstead of dq components of currents in a vector controlscheme. The main features of the proposed model comparedto conventional models in the dq frame of reference arerobustness and simplicity of realization. The sequential loopclosing technique is adopted to design a multivariable controlsystem including six compensators for a DFIG wind energysystem to capture the maximum wind power and to inject therequired reactive power to the generator. In this paperSVPWM method is used for better controlling of converters.It also provides fault ride through method to protect theconverter during a fault. The time-domain simulation of thestudy system is presented by using MATLAB Simulink to testthe system robustness, to validate the proposed model and toshow the enhanced tracking capability