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Found 25 results.

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.

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.

Development of Nanotechnology-based High-performance Opaque & Transparent Insulation Systems for Energy-efficient Buildings (NANOINSULATE)

NANOINSULATE will develop durable, robust, cost-effective opaque and transparent vacuum insulation panels (VIPs) incorporating new nanotechnology-based core materials (nanofoams, aerogels, aerogel composites) and high-barrier films that are up to four times more energy efficient than current solutions. These new systems will provide product lifetimes in excess of 50 years suitable for a variety of new-build and retrofit building applications. Initial building simulations based on the anticipated final properties of the VIPs indicate reductions in heating demand of up to 74Prozent and CO2 emissions of up to 46Prozent for Madrid, Spain and up to 61Prozent and 55Prozent respectively for Stuttgart, Germany for a building renovation which reduces the U-value of the walls and roof from 2.0 W m-2 K-1 to 0.2 W m-2 K-1. This reduction could be achieved with NANOINSULATE products that are only 25 mm thick, giving a cost-effective renovation without the need of changing all the reveals and ledges. Similarly, significant reductions in U-values of transparent VIPs (3 W m-2 K-1 to 0.5 W m-2 K-1) are shown by substituting double glazed units in existing building stock. Six industrial & four research based partners from seven EU countries will come together to engineer novel solutions capable of being mass produced. Target final manufacturing costs for insulation board (production rates above 5 million m2/year) are less than 7 m-2 for a U-value of 0.2 W m-2 K-1. NANOINSULATE will demonstrate its developments at construction sites across Europe. A Lifecycle Assessment, together with a safety and service-life costing analysis, will be undertaken to prove economic viability. NANOINSULATE demonstrates strong relevance to the objectives and expected impacts of both the specific call text of the Public-Private Partnership Energy-efficient Buildings topic New nanotechnology-based high performance insulation systems for energy efficiency within the 2010 NMP Work Programme and the wider NMP & Energy Thematic Priorities. Prime Contractor: Kingsplan Research and Developments Ltd.; Kingscourt; Irland.

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.

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.

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.

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.

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.

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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