Forests play a central role for global carbon cycling and biodiversity. Yet, the unabated continuation of climate change and increasing anthropogenic pressure on forest resources are altering forest ecosystems by modifying species composition and ecosystem processes. Increasing temperatures are likely to increase decomposition rates and thus carbon emissions, while the opposite effect may be expected from loss of decomposer biodiversity as land-use intensity increases. However, it remains unknown how climate change and land use interactively shape decomposer communities, decomposition rates and carbon fluxes. This limits the ability to model the future of the global forest carbon sink as well as of forest policy and management to counteract undesired developments. Here, I will investigate the joint effects of climate change and land use on decomposer communities and carbon fluxes from wood decomposition at the global scale, as well as the underlying processes and mechanisms. Making use of an operating network of 60 research sites on six continents, I will study how biodiversity-decomposition relationships and effects of land use change along global climate gradients. Empirical results will be used to model carbon fluxes from wood decomposition at the global scale and to generate projections of carbon fluxes under different scenarios of forest use and climate change. Extensive experiments will be conducted both in the field and in walk-in climate chambers to identify which facet of biodiversity drives wood decomposition and to unravel the mechanisms behind the climate-dependency of biodiversity-decomposition relationships. The BIOCOMP project will bring about a new level of understanding of how biodiversity and carbon cycling in forest ecosystems worldwide will change as a result of climate change and land use, and it will provide the data and strategies to tackle one of the most pressing challenges of current climate and forest policy.
Conventional robots usually consist of heavy rigid components, such as engines, gearboxes and rigid linkages that are made of high-density materials. Although they can perform complex movements and processes, they are typically not able to perform movements similar to those of biological models. Dielectric elastomer actuators (DEAs) allow flexible mechanisms to behave as artificial muscles. They typically consist of mechanically pre-strained elastomer membranes and compliant electrodes. They are lightweight and can produce impressive muscle-like strains. DEAs are capable of mimicking the well-established antagonistic principle found in nature. To control dielectric elastomer actuators, complex, expensive and external electronic control units are generally required, which often makes the practical application of DEA complicated and rather attractive of commercial products. However, dielectric elastomers can also act as sensors and piezoresistive switches (Dielectric elastomer switches - DESs), enabling the integration of monitoring and control functions in compliant components themselves. During the proposed project at the Biomimetics Laboratory at the University of Auckland and the TU Dresden, dielectric elastomer components will be used in complex soft robotic systems. The aim of the proposed project is to integrate sensing, signal processing and actuation by the use of only flexible dielectric elastomer components in soft robotic structures without using conventional electronics. Based on the current knowledge of the DESs at the Biomimetics Laboratory, sensor-actuator systems comprising dielectric elastomer (DE) sensors, actuators and logic switches will be designed, to monitor, evaluate and react to certain environmental conditions. The developed laboratory scale processes will be transferred to modern production technologies at the Solid State Electronics Laboratory in Dresden in cooperation with the Werner-Hartmann-Zentrum for technologies of electronics.
The goal of this research proposal is to unravel the cellular and molecular mechanisms for the ability of the adult zebrafish brain to regenerate itself after a lesion, and to compare these mechanisms in the non-regenerating mammalian brain. The corresponding mechanisms, if reactivated, may rekindle regeneration also in mammalian brains. Specifically, we focus on identifying the endogeneous stem and progenitor cells that contribute to neural regeneration in zebrafish, by genetic lineage tracing experiments under conditions of regeneration. We have begun to identify the genes and mechanisms controlling regeneration ability in these cells by transcriptome analysis of specific cell types isolated by FACS sorting and transcriptome analysis, which has revealed a key positive role for inflammation as a trigger in regeneration. The resulting candidate genes are functionally tested in adult zebrafish brains for their requirement and sufficiency to elicit or contribute to brain regeneration. If confirmed, we will test for the function of such genes and mechanism in mammalian tissue culture models of regeneration, and determine in adult mouse brain in vivo whether they are candidates to be tested in mammalian brain regeneration. Functional knock-out, knock-in and viral expression tests of such genes and mechanisms in vivo in mice will determine their ability to rekindle regeneration in the lesioned mammalian brain. This research proposal will provide fundamental insights into the cellular and molecular mechanisms controlling the process of brain regeneration in vertebrates, and will thus suggest avenues for future progenitor cell-based therapies of the injured or diseased human brain.
The proposal aims to transfer the results of the scientific research on design procedures of Late Gothic vaults into the practice of restoration of the architectural heritage. These structures are extremely complex in their geometry, with complicated meshes of ribs soaring along three-dimensional curves and intersecting on multiple levels at the keystones. About the principles of their geometric design and the way of how the instructions for producing their single stone elements were formulated, a deeper understanding has been gained in the current research. However, at present this knowledge is not available in the restoration practice. Hence, in case of retrofit or the necessity of reproducing damaged stone elements, there is the risk of altering the peculiar geometric features and distorting the character of these unique masterpieces of historic architecture. A practical implementation of the scientific results, with the potential of significantly improving the quality of maintenance and restoration, can be achieved by defining practical working procedures that reproduce the original design principles, by documenting these procedures and by creating a demonstrator. For the development of these proposed working procedures, their testing and their dissemination among apprentices and specialized stone-masons, a collaboration with the Workshops or Fabrics of several major Cathedrals will be established, which are the institutions engaged in the conservation of Late Mediaeval and Early Modern stone constructions and in keeping alive the historical technical knowledge of stone masonry.