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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.

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.

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.

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.

Demonstrating Industrial Scale Second Generation Bioethanol Production - KAlundborg CELLulosic Ethanol plant (KACELLE)

The aim of this project is to bring the patented Inbicon Core technology for 2nd generation bio-ethanol production from a pre-commercial to a full commercial level, making the technology available in the market and attractive to investors in 4 - 5 years. The technology was developed in steps (also partly EU funded) and now a 4 t/hr biomass to ethanol plant is being built in Kalundborg in Denmark. The plant will be in operation in the fall of 2009 and will produce 5 million litres of ethanol annually. More than 10 years of development has brought about a robust process capable of producing substantial quantities of ethanol from biomass. The next necessary step is to reduce the production costs, thus making the process feasible. In this proposal we apply for funding to demonstrate the 4 t/hr at industrial scale and optimise the plant to lower the production costs for ethanol through: Improving the capacity of the plant, reducing the energy consumption and water balance, adding a fermentation step for C5 sugars and recycle the enzymes in the process. Ultimately we will improve the capacity of the plant to become a 8-10 t/hr plant by developing the process from being partly continuous to operate in a truly commercial continuous mode. We expect this to result in a significant cost-cut in ethanol production expenses. The ethanol produced will be characterized and tested in engine test-rigs and in car-fleet, thus covering the whole value chain from the straw entrance to the gate of the ethanol plant production to end-users in cars. The process will be assessed from an environmental perspective through LCA analysis and results will be published for scientific purpose and for expanding the use of the technology to use for future business partners. The team of partners in this project are those who have a relevant business role in the demonstration of this value chain, a research center and universities with competences in key areas.

Transgenic strawberries and their wild relatives - a potential model for extinction by hybridisation

Do genetically modified strawberries pose a threat to wild varieties? Do genetically modified strawberries pose a threat to wild varieties? Strawberries are an important niche product in Switzerland. Breeders are experimenting with genetic engineering methods to enhance the marketability of this product. There are risks inherent in this approach since the transfer of modified genes to wild strawberries could endanger the continued existence of the wild varieties. Background Transgenic varieties of strawberry with higher yields and enhanced root development already exist. The first release trials have already begun in Italy. However, if transgenic varieties of strawberry cross-breed with wild ones, there may be negative effects. The hybrids produced in this way are often sterile, yet by back-crossing with wild types or by producing prolific numbers of offshoots they can penetrate the native flora and displace it. Objectives This project has two basic goals. First, it seeks to assess the extent to which transgenic strawberries are capable of cross-breeding with their wild relatives. Second, it seeks to investigate the possible ecological impact of such crossbreeding under various environmental conditions in order to assess the risks associated with cultivating transgenic strawberries in the open. Methods Greenhouse experiments with honey bees, the most important pollinators of strawberries, will be carried out to show whether and how efficiently natural pollination occurs between transgenic and wild strawberries. Genetic methods will be used to determine how frequently foreign pollination between cultivated and wild strawberries has already occurred in the open in the past. The possible ecological implications of this will be quantified using life history data such as growth and competitive pressure. In these experiments, transgenic and artificially cross-bred strawberries from the laboratory will be planted in various soils. Significance The cultivation of transgenic plants is associated with potential risks for their wild relatives. Scientists have warned that the latter could become extinct as a result of undesirable cross-breeding. However, to date the true extent of these risks has barely been investigated. This project aims to close this gap by generating basic data with transgenic and wild strawberries as model organisms. These data could ultimately be relevant for other related crop plants such as apple trees or cherry trees.

Natural product lead discovery at the microgram scale - an integrated approach

Natural products remain an important source for drugs and a source of inspiration for medicinal chemists for the design of synthetic drugs and probes for the study of biological functions. The contribution of academic laboratories in natural products discovery has been substantial. The limiting factor of pharmaceutical natural product research has been with the tedious process of purification and identification of the lead molecules from the highly complex crude extract. Recent technological advances enable now a miniaturization of the screening and discovery process for natural product leads. The proposal here is for the purchase of a 500 MHz NMR spectrometer specifically equipped for the measurement of mass limited samples. It includes a recently commercialized 1 mm probe and autosampler and is capable of recording 1D and 2D NMR spectra with microgram (20-100 myg) amounts of natural products and synthetic drug-like molecules. The spectrometer is configured to fit into the technology platforms and the workflows of the Drug Screening Group of the Swiss Tropical Institute and the Institute of Pharmaceutical Biology. The instrument shall be used for various interdisciplinary projects of the two principal applicants and for a consortium which is being established. The major use will be for HPLC-based lead discovery in the area of Alzheimer's disease, Malaria, and neglected tropical diseases. The instrument will also be employed for metabolic fingerprinting of selected plants and phytomedicines. A third application will be in the analysis of compound libraries from external sources which are screened by the applicants in the context of the principal projects. An NMR instrument with this configuration is currently not in operation at a Swiss university. It is the missing link in a technology platform established at the laboratories of the two applicants. This platform should enable a paradigm shift in the way how natural product leads are identified, namely by miniaturizing the entire process of screening, separation and lead identification to the microgram level. A significant gain in efficiency of the discovery process and, thus, in research productivity, both qualitative and quantitative, is anticipated. The equipment will also be of interest to all those scientists in the biomedical sciences who need structural information from mass limited samples such as, for example drug metabolites.

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