Bøger udgivet af Sudwestdeutscher Verlag Fur Hochschulschriften AG

Nanocomposites based on hyperbranched polymers (HBPs) and layered silicates as nanofillers are a relatively new class of nanocomposites. Due to their unique physical/chemical properties, they have attracted scientific interests. This book provides to a better understand the structure-dynamics-properties relationship, for different types of HBP/ kaolinite (Ka) nanocomposites via a combination of different methods. The molecular dynamics was studied by means of broadband dielectric spectroscopy (BDS). The dielectric spectra are dominated by the conductivity contribution at higher temperatures, for all samples investigated. The segmental dynamics (¿-relaxation) revealed by specific heat spectroscopy (SHS). In the framework of this book, it was evident that the method of the preparation of the nanostructures, the end-groups of HBPs, the concentration of the nanofiller, and the treatment of its surface have a significant effect on preparing exfoliated or intercalated nanocomposites. Thus, new nanocomposites with tailor-made properties could be obtained. To sum up, at the moment, it looks like that there is still no limit and no end for studies on HBPs nanocomposites.

Phytic acid or phytate is abundant in many seeds and fruits, where it represents the major storage form of phosphorus (P) in plants and contributes significantly to total seed P. Phytic acid occurs also in other plant organs. Each of this chapters addresses different aspects of the main question: Does phytic acid occur in green leaves and what are its possible functions? All the chapters underwent the review process for assuring scientific accuracy and includes all the necessary information regarding the phytic acid plays an important ecological role in leaves as it is stored first, and then remobilized and recycled during the season. This book is an excellent and comprehensive reference material for phytate in leaves. Biologist, Ecologist, Agriculturists, post-graduate students of agricultural and environmental and the general public. This book covers different sets of depth knowledge about phytate in leaves written in a systematic and comprehensive manner. Providing the novel and powerful options for understanding mechanisms for phytic acid in plants and movement from soil to plants-stores in leaves. I hope this book will meet your expectations.

Hippocampal theta oscillations support encoding of an animal¿s position during spatial navigation and theta frequency is correlated with running speed. However, whether hippocampal theta oscillations regulate locomotion remained a long-standing question. Only since recently distinct brain pathways can be manipulated with high spatial and temporal precision using optogenetics. In this study hippocampal theta oscillations were entrained by optogenetically exciting medial septum pacemaker cells projecting to the hippocampus at theta frequencies. The entrainment promoted a lower variability of theta amplitude which mediated slower and more regular running speed. Pharmaco- or optogenetic inhibition of the main hippocampal subcortical output, to the lateral septum, prevented the behavioral effect of the entrainment. In conclusion, the findings give evidence that hippocampal theta oscillations can regulate locomotor speed via a lateral septum pathway.

The coordination of robot teams plays an increasingly important role in the development of future robot and automation systems. More complex tasks can be approached and already existing solutions can be significantly improved by using multiple robots in a cooperative fashion. This thesis presents several scenarios, including cooperation between air and ground vehicles, exploration scenarios and monitoring tasks. The presented solutions are built on a mathematical foundation and solved through optimization methods. Simulations provide illustration and indicate the applicability of the presented ideas.

Reactive species (RS) play important roles in vital physiological processes. However, excessive RS damages cells and may contribute to the onset of several diseases. Therefore, there is a clear demand for sensitive probes that precisely monitor cellular RS with a high spatio-temporal resolution to understand the multifaceted role of RS in redox biology. Genetically encoded redox probes derived from green fluorescent protein (GFP), such as roGFP2 and Grx1-roGFP2, are promising tools for quantitative and dynamic observation of RS with spatio-temporal resolution. However, the excitation light used to read-out the fluorescence of these proteins can lead to irreversible modification of cell constituents, which may result in either immediate or long-lasting alterations of molecular functions.

Though northern Germany is regarded as a low-seismicity area, the region was affected by 77 earthquakes with magnitudes be-tween 0.5 and 4.3 ML within the time period of January, 1st 1993 to December, 31st 2016. The aim of this thesis is to analyze trigger mechanisms for the recent earthquakes in NW Germany in order to better differentiate between potential anthropogenic and natural tectonic drivers. Possible trigger mechanisms are stress changes related to either the extraction of natural gas and/or processes of the ongoing glacial isostatic adjustment.

The demand for large format round steel billet has been increasing in past decades. As a new casting method, semi-continuous casting (SCC) process, which attempts to combine the merits of ingot casting and continuous casting techniques, is becoming a competitive technique in modern steel plants to produce large round. However, understanding to the process regarding to the formation of as-solidified structure, macrosegregation, porosity, and so on is not very clear. The objective of this work is to use a three-phase columnarequiaxed solidification model to simulate solidification process of SCC, evaluating the aforementioned issues and supplying instructive suggestions to the industry. This numerical model is originally developed by Wu and Ludwig [Metall. Mater. Trans. A, 2006, p.1613]. In order to model the SCC process, the numerical model was extended. Verifications of the extended model were made in several cases at different scales from laboratory benchmark to practical SCC strand.

Thermophilic Campylobacter are well recognized as the leading cause of bacterial foodborne gastroenteritis worldwide. Campylobacter are microaerophilic growing, Gram-negative, curved corkscrew shaped and show motility. They colonize the intestine of many wild and domestic animals, particularly that of poultry. Knowledge on Campylobacter is limited in many developing countries, particularly in Vietnam and Kenya. Studies on the epidemiology of Campylobacter based on molecular techniques are limited for both countries. Additionally, some common characteristics of chicken production and food consumption habits are in common, Vietnam and Kenya, e.g. close proximity of human and animal production, low biosecurity levels and hygiene standards, overuse of antibiotics in animal feed. These factors have been discussed to contribute to Campylobacter transmission to human. There are many gaps that need to be filled in epidemiological studies of Campylobacter in these countries. Therefore, the aim of this work is on emphasizing Campylobacter as a foodborne pathogens in Vietnam and Kenya.