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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.

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.

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.

Storage of hydrogen in hydrides

Hydrogen is the ideal synthetic fuel to convert chemical energy into electrical energy or into motive power because it is light weight, highly abundant and its oxidation product is vapor of water. Thus its usage helps to reduce the greenhouse gases and it conserves fossile resources. There is even a clean way to produce hydrogen by electrolysis of water by means of photo voltaics (SvW06, VSM05, PMM05). There are various possibilities to store the hydrogen for later use: Liquid and gaseous hydrogen can be stored in a pressure vessel, hydrogen can be adsorped on large surface areas of solids, and finally crystal lattices of metals or other compounds can be used as the storage system, where hydrogen is dissolved either on interstitial or on regular lattice sites by substitution (SvW06, San99). The latter process and its reversal is called hydriding respectively dehydriding. The subject of this proposal is the modeling and simulation of that process. The main problem of a rechargeable lithium-ion battery is likewise a storage problem, because in a rechargeable battery, both the anode and cathode do not directly take part in the electrochemical process that converts chemical energy into electrical energy, rather they act as host systems for the electron spending element, which is here lithium (Li). During the last month the applicant developed and exploited a mathematical model that is capable to capture the storage problem of an iron phosphate (FePO4) cathode, where the Li atoms are stored on interstitial lattice sites (DGJ07).

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.

Health impact of engineered metal and metal oxide nanoparticles: Response, bioimaging and distribution at cellular and body level (HINAMOX)

Objective: Metal oxide and metal NPs are particularly dangerous for two reasons: their special catalytic activity coming from the properties of their nanointerface may interfere with numerous intracellular biochemical processes and the decomposition of NPs and the ion leakage could heavily interfere with the intracellular free metal ion homeostasis, which is essential for cell metabolism. A very specific problem is the difficulty of localizing and quantifying them in cells. Obtaining dose effect relationships is not simple, because of the unknown amount of material present in affected cells. The following main points will be addressed in this proposal: - Design and synthesis of metal oxide and metal NPs, which can be traced by SPECT, PET, and fluorescence techniques and the appropriate characterization of these NPs. - Application of label-free techniques, such as IBM and EM to ensure that the radioactive and fluorescent constituents do not modify the cytological and organismic response by themselves. - Characterization of the uptake, distribution kinetics and NP release at the level of the organism. - Study of the interaction of NPs with plasma components forming complexes with NPs and the assessment of their possible impact on the uptake compared with that of bare or capped particles. - Quantification and localization of metallic NPs in immune competent cells is a key task for the establishment of proper dose-response correlations. A technique applicable with living cells as ultimate control will be IBM, capable of detecting single metal NPs in cells at different depths. - Development of sophisticated cell physiological approaches focusing on the determination of oxidative activity, cytokine production and adaptive processes concerning signalling pathways beyond standard vitality tests. The research project will indicate toxic levels of various NPs and sub-toxic effects will be investigated by analysing the signalling response of immune cells.

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

Development of new intermodal loading units and dedicated adaptors for the trimodal transport of bulk materials in Europe (TRIMOTRANS)

Objective: The constitution of the common European market is accompanied by continuously increasing cross-border goods and passenger traffic. Road transportation is facing a rapidly increasing congestion whilein the contrary the available capacities in railway transportation as well as inland waterwaytransportation are being underutilised. A redistribution of the carriage of goods is urgently needed, but up to now the most important obstacles consists in the incompatible interfaces between the various carriers and the diversity of loading devices being used in the EU. Main objective of the project is the development of new intermodal loading units including devices (ISO-bulk container and Roll-off container), capable adaptors and mobile fixtures suitable for the trimodal transport of bulk and packaged goods at road, railway and inland waterways. Essential element of the project is the design and integration of innovative adaptors for lifting and shifting operations of the loading units. This will lead to an optimum on intermodal compatibility. The goals are in conformity with the aims of the Specific Programme 'Sustainable Surface Transport', research domain 3.16. 'Development of equipment for fast loading / unloading of intermodal transport units'. By application of the new loading units the logistic chain can be set up without changing the loading unit throughout the whole door-to-door transport process. The transhipping procedures do not require crane technology any more and the costs will be reduced substantially. The uniformity of the specialinternal features as well as the compliance with the ISO-container dimensions will contribute to the harmonisation of loading units. The projects includes the development of containers, adaptors and mobile units, test and demonstration of two prototypes and dissemination and exploitation of the results. The consortium consists of ten partner with six SMEs from five countries (G, HU, CH, A,CR)

Short-term in vitro assays for long-term toxicity (PREDICTOMICS)

The development of new pharmaceutical compounds will be more efficient if human relevant toxicology information early in the selection process is available. While acute toxicity can be reasonably detected during the early preclinical stages of drug development, long-term toxicity is more difficult to predict, relying almost exclusively on animal experiments Animal experimentation of this kind is expensive and time consuming, raises ethical issues and do not necessarily represent a toxicological relevance to man. This project address the urgent need to develop in vitro based systems which are capable of predicting long term toxicity in humans. The major objectives of this project are:1)To develop advanced cell culture systems which as best possible represents the human liver and kidney in vivo. This will be achieved using combined strategies namely:co-cultures of resident cell types,targeted cell transformation,stem cell technology and new developments in organotypic cell culture (i.e. perfusion cultures and 3D cultures).2)To identify specific early mechanistic markers of toxin induced cell alterations by using integrated genomic,proteomic and cytomic analysis.3)To establish and prevalidate a screening platform (cell systems together with analysis tools) which is unambiguously predictive of toxin induced chronic renal and hepatic disease.This proposal is unique in it's mechanistic integration of the three levels of cellular dynamics (genome, proteome and cytome) together with advanced cell culture technology to detect early events of cellular injury. Only with such an integrated approach will in vitro techniques ever be applicable to predicting chronic toxicity in man. This project,if successful will(1) contribute to the replacement of animal testing in drug development, (2) increase ... Prime Contractor: Fundacion Hospital Universitario 'La Fe', Experimental Hepatology Unit, Research Center; Valencia; Espana.

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