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AsFeP0 - A model concept for in situ investigation or arsenic and phosphate adsorption to predefined iron minerals and to characterize transformation processes of iron minerals

Shallow groundwater of the huge deltaic systems of Asia like the Red River Delta in Vietnam is often enriched in inorganic arsenic (As), threatening the health of millions of residents. The massive abstraction of groundwater in these areas locally causes an irreversible mixing of arsenic-free groundwater resources with arsenic-rich groundwater. Increased concentrations of competitive anions, especially phosphate (PO43-), decrease the immobilization capacity of the sediments. During transport, the mobility of dissolved As in local aquifers is strongly influenced by adsorption to sedimentary and ubiquitously occurring iron(oxyhydr)oxides. Additionally, arsenic-rich groundwater is often enriched in reduced iron (Fe2+) as well, which is capable to react with iron(oxyhydr)oxides, thereby inducing mineral transformations. Such transformations permanently affect the arsenic adsorption and immobilization capacity of the sediments.Within the scope of this research project, the underlying mechanisms related to As transport and the resulting threat to arsenic-free groundwater resources will be characterized in cooperation with the Swiss Federal Institute of Aquatic Science and Technology (Eawag). The research concept aims at assessing the complex interactions within the arsenic-iron-phosphate-system under field conditions at a study site next to the Red River. First, filtration experiments using local groundwater enriched in As and PO43- will be used to determine the As adsorption capacity of different and previously geochemically characterized iron(oxyhydr)oxides. In a second step, sample carrier containing As loaded iron(oxyhydr)oxides will be introduced into surface near aquifer parts of the study site (via existing groundwater monitoring wells). These samples will be exposed to local groundwater characterized by increased As, Fe2+ and PO43- concentrations for the following nine months. Using the in situ exposition of predefined iron(oxyhydr)oxides, it will be possible to distinguish potential mineral transformations and their influences on the As immobilization capacity of the respective iron(oxyhydr)oxides. By combining the results and outcomes of the field experiments, new and important conclusions regarding the mobility of As can be drawn. The data can be used to create a hydrochemical transport model describing reactive As transport within the investigation area. In addition, the results of the in situ exposition experiments will allow to draw conclusions in respective to the long term As immobilization capacity of different iron(oxyhydr)oxides, which is an essential information regarding in situ decontamination techniques.

Diffusion and advection with sorption of anions, cations and non-polar molecules in organo-clays at varying thermo-chemical conditions - validation by analytical methods and molecular simulation

The sorption of anions in geotechnical multibarrier systems of planned high level waste repositories (HLWR) and of non-ionic and organic pollutants in conventional waste disposals are in the center of recent research. In aquatic systems, persistent radionuclides such as 79Se, 99Tc, 129I exist in a form of anions. There is strongly increasing need to find materials with high sorption capacities for such pollutants. Specific requirements on barrier materials are long-term stability of adsorbent under various conditions such as T > 100 C, varying hydrostatic pressure, and the presence of competing ions. Organo-clays are capable to sorb high amounts of cations, anions and non-polar molecules simultaneously having selectivity for certain ions. This project is proposed to improve the understanding of sorption and desorption processes in organo-clays. Additionally, the modification of material properties under varying chemical and thermal conditions will be determined by performing diffusion and advection experiments. Changes by sorption and diffusion will be analyzed by determining surface charge and contact angles. Molecular simulations on models of organo-clays will be conducted in an accord with experiments with aim to understand and analyze experimental results. The computational part of the project will profit from the collaboration of German partner with the group in Vienna, which has a long standing experience in a modeling of clay minerals.

Identification of groundwater nitrogen point source contribution through combined distribute temperature sensing and in-situ UV photometry

Agriculture is the major contributor of nitrogen to ecosystems, both by organic and inorganic fertilizers. Percolation of nitrate to groundwater and further transport to surface waters is assumed to be one of the major pathways in the fate of this nitrogen. The quantification of groundwater and associated nitrate flux to streams is still challenging. In particular because we lack understanding of the spatial distribution and temporal variability of groundwater and associated NO3- fluxes. In this preliminary study we will focus on the identification and quantification of groundwater and associated nitrate fluxes by combining high resolution distributed fiber-optic temperature sensing (DTS) with in situ UV photometry (ProPS). DTS is a new technique that is capable to measure temperature over distances of km with a spatial resolution of ca1 m and an accuracy of 0.01 K. It has been applied successfully to identify and quantify sources of groundwater discharge to streams. ProPS is a submersible UV process photometer, which uses high precision spectral analyses to provide single substance concentrations, in our case NO3-, at minute intervals and a detection limit of less than 0.05 mg l-1 (ca.0.01 mg NO3--Nl-1). We will conduct field experiments using artificial point sources of lateral inflow to test DTS and ProPS based quantification approaches and estimate their uncertainty. The selected study area is the Schwingbach catchment in Hessen, Germany, which has a good monitoring infrastructure. Preliminary research on hydrological fluxes and field observations indicate that the catchment favors the intended study.

Function of BAK1 in plant immunity

In nature most plants are resistant to most pathogens and disease is rather the exception than the rule. A key aspect of this phenomenon is a resistance response called 'innate immunity'. It is based on the host recognition of characteristic microbial molecules, known as MAMPs (Microbe Associated Molecular Patterns), by specific receptors called pattern recognition receptors (PRRs). A paradigm of a MAMP is flagellin, the main building unit of the mobility organ of bacteria. Bacterial flagellin is perceived by the pattern recognition receptor FLS2 (FLagellin Sensing 2) at the surface of plant cells. Binding of flagellin to FLS2 on the outside of the cells induces a set of physiological responses inside the cells, which we can easily measure in our lab and which ultimately contribute to limitation of bacterial invasion and plant resistance. Our lab has focused in the last years in understanding how FLS2, a single pass transmembrane molecule, functions to transmit the signal from outside of the cell to its inside. We could demonstrate that upon stimulation with flagellin, FLS2 associates very quickly at the plasma membrane with a second receptor known as BAK1 (BRI1-Associated Kinase 1). This was initially a big surprise because BAK1 was already known as the co-receptor of the BRI1, a plant hormone receptor which regulates plant development but not plant immunity. More recently we developed an original biochemical approach to label and detect phosphorylated receptors in cell cultures in vivo. This allowed us to show that the transmission of the flagellin signal occurs via phosphorylation of FLS2 and BAK1 within seconds after flagellin perception. In addition we could show that BAK1 is capable of regulating several PRRs other than FLS2 by forming stable complexes. Thus BAK1 appears to be a crucial regulator or plant immunity in addition to its role in plant development. Our recent progress on the plants' flagellin-sensing system was mostly obtained using Arabidopsis as plant model. In view of the ability of BAK1 to form stable complexes with PRRs in a ligand-dependent manner, we are now interested to fish out and identify new PRRs, notably from crop species, using a proteomic approach. The identification of more PRRs in different plants is a very important step toward understanding plant innate immunity. In more general terms, better knowledge about innate immunity is crucial because it may reveal new strategies to fight the devastating impact of some plant diseases.

Development of a high throughput genomics-based test for assessing genotoxic and carcinogenic properties of chemical compounds in vitro (CARCINOGENOMICS)

The major aim of CARCINOGENOMICS is to develop in vitro methods for assessing the carcinogenic potential of compounds, as an alternative to current rodent bioassays for genotoxicity and carcinogenicity. The major goal is to develop a battery of mechanism-based in vitro tests accounting for various modes of carcinogenic action. These tests will be designed to cover major target organs for carcinogenic action e.g. the liver, the lung, and the kidney. The novel assays will be based on the application of 'omics' technologies (i.e. genome-wide transcriptomics as well as metabonomics) to robust in vitro systems (rat/human), thereby also exploring stem cell technology, to generate 'omic' responses from a well-defined set of model compounds causing genotoxicity and carcinogenicity. Phenotypic markers for genotoxic and carcinogenic events will be assessed for the purpose of anchoring gene expression modulations, metabolic profiles and mechanism pathways. Through extensive biostatistics, literature mining, and analysis of molecular-expression datasets, differential genetic pathways will be identified capable of predicting mechanisms of chemical carcinogenesis in vivo. Furthermore, generated transcriptomic and metabonomic data will be integrated into a holistic understanding of systems biology, and applied to build an iterative in silico model of chemical carcinogenesis. Subsequently, predictive gene expression profiles, typically consisting of some 150-250 genes, will be loaded onto high throughput dedicated DNA-chips, thus accelerating the analysis of transcriptomic responses by a factor of 100. It is expected that the outcome of this project will generate a platform enabling the investigation of large numbers of compounds for their genotoxic and carcinogenic potential, as envisaged under the REACH initiative. This will contribute to speeding the identification of potential harmful substances to man, while lowering costs and reducing animal tests. Prime Contractor: Maastricht, University, Health Risk Analysis and Toxicology (Grat); Maastricht, Nederland.

Monitoring changes in biodiversity at regional and continental scales over the past three decades using a dynamic habitat index derived from historical satellite data

Understanding the drivers behind the loss of biodiversity currently observed is of major importance in the context of the global change discussion. For studies of biodiversity at broad spatial scales, satellite remote sensing is the premier source of information, as it is uniquely capable of covering large areas of the Earth at high temporal resolution. The underlying assumption is that satellite-derived geophysical surface parameters, such as vegetation greenness, are related to biodiversity. For that purpose, concepts such as the Dynamic Habitat Index (DHI) were recently developed. The DHI combines information on the overall greenness, the base level of vegetation cover, and vegetation seasonality at a certain location. By comparing the annual DHI with a long term mean, areas undergoing disturbances or recovery events can be delineated, which are indicative of changes in species composition and diversity. The concept of the DHI was developed for data obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS) post-2000. However, for climate change impact studies a longer time series is desirable. The only sensor system suitable for such applications is the Advanced Very High Resolution Radiometer (AVHRR), which has been in orbit on various platforms since the early 1980ies. The purpose of this project was to develop a methodology to derive long term information on habitat conditions at continental scales based on historical satellite data. In particular, the goal was to adopt the principle of the DHI as developed for the MODIS sensor to an AVHRR archive at 1 km spatial resolution over Canada and to analyze long term variations in the DHI. In a first project phase, an AVHRR data set of vegetation greenness, generated in the framework of the project, was validated against the reference MODIS product. The results demonstrated a very good agreement between both data sets for a wide range of vegetation types and on various spatial and temporal scales. A historical baseline of habitat conditions post-1987 based on the DHI was subsequently generated based on the long term AVHRR data. The analysis of the DHI showed that certain areas, particularly northern parts of the Province of Quebec as well as southwestern Canada, experienced significant changes over the past two decades, which may have had significant impacts on species diversity and abundance in these areas. In the future, the methods developed in the framework of this project may be used to obtain information on long term variations in habitat conditions in areas covered by other historical satellite archives, e.g., for Europe based on an AVHRR archive hosted at the University of Bern.

Evolution of plant morphological diversity in plant-insect mutualisms

Most plants rely on insects for their pollination, protection (e.g., from herbivores) and/or seed dispersal, and have formed a mutually beneficial interaction, or mutualism. The current research investigates the evolution of plant traits involved in plant-insect mutualisms. In particular, it focuses on the evolution of extrafloral nectaries (EFNs): secretory structures on plant parts outside the flower, which offer carbohydrate-rich, water-based secretions (=nectar) to ants in return for their protection from herbivores (i.e. protective mutualisms). EFNs occur in some ferns and over hundred families of flowering plants, especially the legume family. However, their phylogenetic distribution within families, morphological diversity and evolution, and evolutionary role are poorly understood. Also EFN plant-ant interactions are known to shape entire tropical and savannah-like ecosystems, but their unexpected occurrence in deserts - where plants need to manage water carefully - has been studied only in a few cacti. This study investigated the diversity and evolution of EFNs at three different levels: (1) in the Leguminosae, the third largest and second economically most important angiosperm family, which also dominates many kinds of vegetation worldwide; (2) in the legume genus Senna, a case study where EFNs represent a key innovation (see past SNF project by B. Marazzi); and (3) in Sonoran Desert plants. Current results show that EFNs occur in species of over 130 legume genera (over twice as many as in the last published account of EFNs in this family). They are particularly abundant in the subfamily Mimosoideae, and may have evolved independently at least 30 times in the family. This incredible number of origins suggests the action of some evolutionary (perhaps genetic) precursor that allowed some clades to evolve EFNs more 'easily' given ceartin selective regimes. Most legume EFNs occur on the (typically pinnate) leaves, less often on stipules and different parts of inflorescences. In Senna, ancestral leaf EFNs appear to have evolved first between the proximal pair of leaflets only (some 40 Million years ago), and later also between the other pairs of leaflets (several times) or only at the base of the leaf stalk (once). In the Sonoran Desert area (including also mountain habitats), EFNs may occur in species from up to 32 families, in several cacti and in particular Leguminosae, dominant in this vegetation. EFNs have apparently been reduced but have been retained in a functional state (i.e., secreting nectar) in most desert legumes, and are thus capable of participating in protective mutualisms with desert ants. This research shows that EFNs are more widespread in plants than previously thought, suggesting that we may have underestimated the role of protective ant-plant interactions in shaping ecosystem ecology and evolution

Development of a GIS-based model for the assessment of regional element balances as a basis for sustainable management of trace elements in agricultural soils

Limiting the input of toxic trace elements into soils is an important task in achieving sustainability of agricultural land use. Excessive accumulation of trace elements in soils is a major issue world-wide. In the EU agriculture is currently under particular pressure to meet stricter standards of sustainability including zero accumulation of contaminants in soils. Monitoring element accumulation in soils by means of element balancing is a very efficient method to gather the information needed to prevent or at least to limit and control soil pollution at an early stage before critical levels are reached, to prioritize decisions on abatement actions and to guide remedial actions. While methods have been developed and are continuously improved to assess element balances in European agro-ecosystems at the farm scale, there is a lack of similar models that are applicable to agricultural systems at regional scales, capable to deal with the problem of a complex data acquisition from very diverse information sources, account for dynamic feedbacks between system components and adequately address spatial redistribution of elements through processes such as erosion. The objective of this project is to develop a model for the assessment of regional element balances that has these capabilities and can deal with spatial data through combination with a GIS. For this purpose we propose to extend the existing regional mass balance model PROTERRA-S with respective dynamic features and to couple it with a GIS. Accounting for the different agricultural, socio-economic and bio-physical subsystems is a challenge that requires a modular approach with high flexibility. The generalized model will be calibrated and tested in a case study of the Swiss Canton Thurgau, for which comprehensive data bases have been already compiled and are available.

Hochleistungstragwerke - HHT - Entwicklung von hochbelastbaren Verbundbauweisen im Holzbau mit faserverstärkten Kunststoffen, technischen Textilien und Formpressholz

Das Gesamtziel des Verbundprojektes besteht darin, dem nachwachsenden Rohstoff Holz durch einen neuartigen Engineering- Baustoff ein weiteres neues Marktsegment und damit einen erhöhten Absatz zu verschaffen. Im Fordergrund steht die Steigerung der Leistungsfähigkeit von Holzkonstruktionen mit Hilfe von Hochleistungsfasern, beanspruchungsgerechten Textilien sowie verdichteten und geformten Hölzern. Hieraus folgen erhebliche Verbesserungen hölzerner Tragkonstruktionen bezüglich Steifigkeit, Festigkeit, Zähigkeit, Dauerhaftigkeit und Materialeffizienz. rnMittelfristige Ziele sind: (1) Die Einführung von Hochleistungshölzern in die praktische Anwendung für hochbelastete Tragwerkskonstruktionen und (2) Die Etablierung von maßgeschneiderten Holzkonstruktionen im Bereich von Sanierungs- und Neubauvorhaben unter Ausnutzung neuer baustofflicher Eigenschaften, beanspruchungsgerechter Verstärkungen und einer neuen Technologie zur Querschnittsbildung. Besonderen Wert bei der Umsetzung der Projektziele legen die Verbundpartner auf eine stark praxisorientierte Ausrichtung der Arbeiten und die Demonstration der Projektergebnisse im Rahmen geeigneter Pilotvorhaben.rnrnIn Druckversuche an axial beanspruchten Rohrstützen wurde das Last-Verformungs-Verhalten der Leichtbauprofile untersucht. Aufgrund des großen Trägheitsmomentes der Rohrquerschnitte wurden bereits für unverstärkte Profile hohe Trag- bzw. Knicklasten ermittelt. Die Versuche an faserverstärkten Profilen haben jedoch gezeigt, dass deutliche Steigerungen hinsichtlich Traglast und Duktilität der Stützen möglich sind. Zur Vorbemessung und Analyse der Versagensmechanismen wurden Standard-Bemessungsgleichungen bzw. einfache analytische Modelle eingesetzt. Diese wurden anhand der experimentell ermittelten Daten verifiziert.rn

Fuel cell power trains and clustering in heavy-duty transports (FELICITAS)

Objective: The FELICITAS consortium proposes an Integrated Project to develop fuel cell (FC) drive trains fuelled with both hydrocarbons and hydrogen. The proposed development work focuses on producing FC systems capable of meeting the exacting demands of heavy-dut y transport for road, rail and marine applications. These systems will be: - Highly efficient, above 60Prozent - Power dense, - Powerful units of 200kW plus, - Durable, robust and reliable. Two of the FC technologies most suitable for heavy-duty transport applic ations are Polymer Electrolyte FuelCells (PEFC) and Solid Oxide Fuel Cells (SOFC). Currently neither technology is capable of meeting the wideranging needs of heavy-duty transport either because of low efficiencies, PEFC, or poor transient performance,SO FC. FELICITAS proposes the development of high power Fuel Cell Clusters (FCC) that group FC systems with other technologies, including batteries, thermal energy and energy recuperation.The FELICITAS consortium will first undertake the definition of the requirements on FC power trains for the different heavy-duty transport modes. This will lead to the development of FC power train concepts, which through the use of advanced multiple simulations, will undertake evaluations of technical parameters, reliab ility and life cycle costs. Alongside the development of appropriate FC power trains the consortium will undertake fundamental research to adapt and improve existing FC and other technologies, including gas turbines, diesel reforming and sensor systems f or their successful deployment in the demanding heavy-duty transport modes. This research work will combine with the FC power trains design and simulation work to provide improved components and systems, together with prototypes and field testing where ap propriate.The FELICITAS consortium approach will substantially improve European FC and associated technology knowledae and know-how in the field of heavv-duty transport.

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