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The role of turgor in rain-cracking of sweet cherry fruit

Das Projekt "The role of turgor in rain-cracking of sweet cherry fruit" wird vom Umweltbundesamt gefördert und von Leibniz Universität Hannover, Institut für Biologische Produktionssysteme, Fachgebiet Obstbau durchgeführt. Rain-cracking limits the production of many soft and fleshy fruit including sweet cherries world wide. Cracking is thought to result from increased water uptake through surface and pedicel. Water uptake increases fruit volume, and hence, turgor of cells (Pcell) and the pressure inside the fruit (Pfruit) and subjects the skin to tangential stress and hence, strain. When the strain exceeds the limits of extensibility the fruit cracks. This hypothesis is referred to as the Pfruit driven strain cracking. Based on this hypothesis cracking is related to two independent groups of factors: (1) water transport characteristics and (2) the intrinsic cracking susceptibility of the fruit defined as the amount of cracking per unit water uptake. The intrinsic cracking susceptibility thus reflects the mechanical constitution of the fruit. Most studies focussed on water transport through the fruit surface (factors 1), but only little information is available on the mechanical constitution (i.e., Pfruit and Pcell, tensile properties such as fracture strain, fracture pressure and modulus of elasticity of the exocarp; factors 2). The few published estimates of Pfruit in sweet cherry are all obtained indirectly (calculated from fruit water potential and osmotic potentials of juice extracts) and unrealistically high. They exceed those measured by pressure probe techniques in mature grape berry by several orders of magnitude. The objective of the proposed project is to test the hypothesis of the Pfruit driven strain cracking. Initially we will focus on establishing systems of widely differing intrinsic cracking susceptibility by varying species (sweet and sour cherry, Ribes and Vaccinium berries, plum, tomato), genotype (within sweet cherry), stage of development and temperature. These systems will then be used for testing the hypothesis of Pfruit driven strain cracking. We will quantify Pfruit und Pcell by pressure probe techniques and compression tests and the mechanical properties of the exocarp using biaxial tensile tests. When the presence of high Pfruit and Pcell is confirmed by direct measurements, subsequent studies will focus on the mode of failure of the exocarp (fracture along vs. across cell walls) and the relationship between failure thresholds and morphometric characteristics of the exocarp. However, when Pfruit und Pcell are low, the hypothesis of Pfruit driven strain cracking must be rejected and the mechanistic basis for low pressures (presence of apoplastic solutes) clarified on a temporal (in the course of development) and a spatial scale (exocarp vs. mesocarp). We focus on sweet cherry, because detailed information on this species and experience in extending the short harvest period is available. Where appropriate, other cracking susceptible species (sour cherry, plum, Vaccinium, Ribes, tomato) will be included to further extend the experimental period and to maximize the range in intrinsic cracking susceptibility.

ICCE2008

Das Projekt "ICCE2008" wird vom Umweltbundesamt gefördert und von Bundesanstalt für Wasserbau durchgeführt. Die 31st International Conference on Coastal Engineering ICCE2008 findet vom 31. August bis 5. September 2008 in Hamburg mit ca. 650 Teilnehmern statt. Schwerpunktthemen sind Küstenprozesse, Häfen und Wasserstraßen, Coastal Environment, Küstenrisiken und Küstenentwicklung. Zusätzlich werden Short Courses zu verschiedenen Themen des Küsteningenieurwesens angeboten, die sich insbesondere an Studenten des Küsteningenieurwesens und des Wasserbaus, Doktoranden und interessierte Teilnehmer aus Praxis und Wissenschaft richten. Die eingereichten Abstracts der zum Vortrag bzw. als Poster akzeptierten Beiträge werden vor der Konferenz (15.08.2008) allen Teilnehmern in geeigneter Weise zur Verfügung gestellt. Vor Konferenzbeginn (31.08.2008) werden zwei Short Courses zu Morphodynamik (Workshop, 9 Referenten) und dem gerade erschienenen European Overtopping Manual (Workshop, 6 Referenten) durchgeführt. Mit dem Druck der 4-bändigen Proceedings (15.09.2008) werden die Konferenzbeiträge nachhaltig gesichert. Deutschland leistet mit Ausrichtung der ICCE2008 einen wichtigen Beitrag zum Küsteningenieurwesen und unterstreicht die Bedeutung deutscher Forschung.

Energy Storage for Direct Steam Solar Power Plants (DISTOR)

Das Projekt "Energy Storage for Direct Steam Solar Power Plants (DISTOR)" wird vom Umweltbundesamt gefördert und von Deutsches Zentrum für Luft- und Raumfahrt e.V., Institut für Technische Thermodynamik durchgeführt. Objective: Solar thermal power plants represent today's most economic systems to generate electricity from solar insulation in them-range in regions like the Mediterranean area. By demonstrating the feasibility of direct steam generation in the absorber pipes European industry and research institutions have gained a leading position in this technology area. A key element foray successful market penetration is the availability of storage systems to reduce the dependence on the course of solarinsolation. The most important benefits result from -reduced internal costs due to increased efficiency and extended utilisation of the power block-facilitating the integration of a solar power plant into an electrical grid-adoption of electricity production to the demand thus increasing revenues Efficient storage systems for steam power plants demand transfer of energy during the charging/discharging process at constant temperatures. The DISTOR project focuses on the development of systems using phase change materials (PCM) as storage media. In order to accelerate the development, the DISTOR project is based on parallel research on three different storage concepts. These concepts include innovative aspects like encapsulated PCM, evaporation heat transfer and new design concepts. This parallel approach takes advantage of synergy effects and will enable the identification of the most promising storage concept. A consortium covering the various aspects of design and manufacturing has been formed from manufacturers, engineering companies and research institutions experienced in solar thermal power plants and PCM technology. The project will provide advanced storage material based on PCM for the temperature range of 200-300 C adapted to the needs of Direct Steam generation thus expanding Europe's strong position in solar thermal power plants.

Effects of nurse tree species on growth, environment and physiology of underplanted Toona ciliata (F. Muell.)

Das Projekt "Effects of nurse tree species on growth, environment and physiology of underplanted Toona ciliata (F. Muell.)" wird vom Umweltbundesamt gefördert und von Universität Freiburg, Waldbau-Institut durchgeführt. Toona ciliata (Australian red cedar) is highly valued for veneer and furniture production and endangered in its natural ecosystems due to exploitation. This work aims to improve the availability of this wood on the market and help reduce pressure on the species in its native environment. An afforestation project cultivating Toona ciliata was introduced to the study site in Misiones, Argentina. The local cultivation faces losses caused by drought and frost, because T. ciliata requires overstory protection when young. Consequently, Grevillea robusta, Pinus elliottii x Pinus caribaea, and Pinus taeda, nurse tree species which also produce sought-after wood were chosen to provide protection. One-year-old T. ciliata seedlings were planted underneath each of the six-year-old nurse species. An inventory after one year indicated that both survival and height increment were highest underneath G. robusta and lowest underneath P. elliottii x P. caribaea. In this study I am examining possible facilitation and competition mechanisms between the overstory and understory T. ciliata. Extensive empirical data collected over the course of 3 years will be utilized to project potential growth scenarios for several rotations using a computer based forest growth model.

Technical Support for the revision of ecolabel and green public procurement GPP Criteria Lot 1

Das Projekt "Technical Support for the revision of ecolabel and green public procurement GPP Criteria Lot 1" wird vom Umweltbundesamt gefördert und von Öko-Institut. Institut für angewandte Ökologie e.V. durchgeführt. The project's objective is to support JRC IPTS in revising the existing Ecolabel and GPP criteria of personal computers and notebook computers. The priority in this revision process is to first analyse which of the existing criteria and the supporting evidence are still valid and to identify the additional research that should be carried out. Potential additional criteria can be developed, if identified as necessary in the course of the study. The study starts with a definition of the scope; the necessarity for new or revised Ecolabel and GPP criteria is based on a market analysis and a technical analysis with research on the most significant environmental impacts during the whole life cycle of the products. This also includes the application of a consistent methodological approach regarding the hazardous substances criteria. Based on these findings, the improvement potential will be derived resulting in a proposal for a revised Ecolabel and GPP criteria set for desktop and notebook computers which will be discussed in a European stakeholder process.

Principles, tools and systems to extend spatial planning on water courses (WATERSKETCH)

Das Projekt "Principles, tools and systems to extend spatial planning on water courses (WATERSKETCH)" wird vom Umweltbundesamt gefördert und von TuTech Innovation GmbH durchgeführt. Flüsse haben zahlreiche unterschiedliche Funktionen: Sie sind beispielsweise Verkehrsweg, Stromlieferant, Lebensraum für Tiere und Erholungsgebiet für Menschen. Wirtschaftlich und sozial kommt ihnen große Bedeutung zu. Um all diesen Facetten gerecht zu werden, will das Interreg III B Ostseeprojekt 'Watersketch' internationale Strategien für ein erfolgreiches Flussmanagement entwickeln und praxisbezogene Tools erarbeiten. 'Watersketch' will Planungsansätze liefern, die zu einem verbesserten Flussmanagement in der Ostseeregion führen sollen. Die Partner betrachten differenziert die Raum- und Investitionsplanung für ausgewählte Flüsse und entwickeln Strategien für eine nachhaltige Nutzung der Wasserstraßen. Die Ergebnisse stellen Entscheidungshilfen für Raumplaner dar, die ökonomische, soziale und ökologische Elemente gleichermaßen berücksichtigen. Ein Handbuch macht die Ergebnisse auch für andere nutzbar. Die nachhaltige Nutzung und ein besseres Flussmanagement werden damit in weiteren Ländern gefördert. Hauptauftragnehmer: Finnish Environment Institute, Oulun yliopisto (FI).

Technical Support for the revision of ecolabel and green public procurement GPP Criteria Lot 4

Das Projekt "Technical Support for the revision of ecolabel and green public procurement GPP Criteria Lot 4" wird vom Umweltbundesamt gefördert und von Öko-Institut. Institut für angewandte Ökologie e.V. durchgeführt. The project's objective is to support JRC IPTS in revising the existing Ecolabel and GPP criteria of televisions. The priority in this revision process is to first analyse which of the existing criteria and the supporting evidence are still valid and to identify the additional research that should be carried out. Potential additional criteria can be developed, if identified as necessary in the course of the study. The study starts with a definition of the scope; the necessarity for new or revised Ecolabel and GPP criteria is based on a market analysis and a technical analysis with research on the most significant environmental impacts during the whole life cycle of the products. This also includes the application of a consistent methodological approach regarding the hazardous substances criteria. Based on these findings, the improvement potential will be derived resulting in a proposal for a revised Ecolabel and GPP criteria set for televisions which will be discussed in a European stakeholder process.

Impact of urbanisation on the allergenicity of birch pollen grains

Das Projekt "Impact of urbanisation on the allergenicity of birch pollen grains" wird vom Umweltbundesamt gefördert und von Technische Universität München, Fakultät für Medizin, Klinik und Poliklinik für Dermatologie und Allergologie am Biederstein durchgeführt. Evidence is compelling for a positive correlation between urbanisation and increment of allergic sensitisation and diseases. The reason for this association is not clear to date. Some data point to a pro-allergic effect of anthropogenic factors on susceptible individuals. Data analysing the impact of environmental - natural and anthropogenic - factors on the allergenicity of allergen carriers such as pollen grains are scarce, and if applicable only taken from in vitro experimental designs. This study will analyse one of the most common allergy inducers in northern Europe - the birch pollen. Under natural exposure conditions, birch pollen will be analysed with respect to their allergenicity. Within an interdisciplinary research team this study will evaluate the effect of natural (e.g. soil, climate, genetic background) and anthropogenic (e.g. traffic pollutants) factors on birch pollen in a holistic approach including analysis of allergen bioavailability, release of pollen associated lipid mediators from birch pollen grains, in vitro immunostimulatory activity and in vivo allergenic potential. These data collected in the time course of three years will significantly add to our understanding how urbanisation and climate change influence the allergenicity of birch pollen and will help us in the future to set up primary prevention studies.

Generic Fuel Cell Modelling Environment (GENFC)

Das Projekt "Generic Fuel Cell Modelling Environment (GENFC)" wird vom Umweltbundesamt gefördert und von Forschungszentrum Jülich GmbH, Institut für Werkstoffe und Verfahren der Energietechnik durchgeführt. Objective: The GenFC proposal addresses the topic 'Generic tools for FC systems modelling, testing, safety and quality assurance' under the activity code SUSTDEV-1.2.1: Fuel cells including their applications. It falls into research activities having an impact in the medium to long term. The overall goal of GenFC is to provide a generic modelling tool to fuel cell and fuel cell systems developers making fuel cell modelling expert knowledge available to all of them. The fuel cell and fuel cell systems developers can us e this tool to improve and accelerate fuel cell development and to contribute to a future success of the fuel cell technology. It is believed that from the fuel cell (hardware) developer's point of view, a fuel cell modelling environment is desirable which can be used for simulation tasks exactly catering to the demand of the application engineer. The integrated modelling tool will assist fuel cell developers to improve their design- and optimisation processes in terms of accelerating development cycles, l owering costs, improving quality and hence also safety. The user of such a modelling environment will be able to choose through a user friendly interface a model out of a set of different types of fuel cells. Each type of fuel cell will be available in dif ferent implementations and each implementation is suitable for a particular application. The consortium consists of fuel cell technology developers, specific software providers, software engineers and fuel cell model users. Existing and in the course of t he project to be developed models and hardware in the loop systems for different types of fuel cells on all levels from system integration, via stack and cell down to electrode processes, are integrated in the tool and interfaced with a common data-base fo r process and design parameters. GenFC can help establish a competitive fuel cell industry in Europe contributing to the great challenge of migrating from a fossil fuel based economy to a sustainable one.

Improving the Livelihood of the Rural Population through the Production of Bushmeat in Ghana

Das Projekt "Improving the Livelihood of the Rural Population through the Production of Bushmeat in Ghana" wird vom Umweltbundesamt gefördert und von Universität Hamburg, Arbeitsbereich für Weltforstwirtschaft und Institut für Weltforstwirtschaft des Friedrich-Löffler-Institut, Bundesforschungsinstitut für Tiergesundheit durchgeführt. Background: Ghanas transition forests, neighbouring savannahs and timber plantations in the Ashanti region face a constant degradation due to the increased occurrence of fires. In most cases the fires are deliberately set by rural people for hunting purposes. Main target is a cane rat, here called grasscutter (Thryonomys swinderianus), whose bushmeat is highly esteemed throughout the country. The animal is a wild herbivorous rodent of subhumid areas in Africa south of the Sahara. The grasscutter meat is an important source of animal protein. Existing high-value timber plantations (mainly Teak, Tectona grandis) are affected by fires for hunting purposes. Thus resulting in growth reduction, loss of biomass or even complete destruction of the forest stands. It became obvious that solutions had to be sought for the reduction of the fire risk. Objectives: Since 2004 the Institute for World Forestry of the Federal Research Centre for Forestry and Forest Products, Hamburg, Germany is cooperating with a Ghanaian timber plantation company (DuPaul Wood Treatment Ltd.) the German Foundation for Forest Conservation in Africa (Stiftung Walderhaltung in Afrika) and the Center for International Migration with the purpose to improve the livelihood of the rural population in the surroundings of the forest plantation sites and simultaneously to safeguard and improve the timber plantations. The introduction of grasscutter rearing systems to local farmers accompanied by permanent agricultural and agroforestry practices appeared to be a promising approach for the prevention of fires in the susceptible areas. Additionally a functioning grasscutter breeding system could contribute to the improvement of food security, development of income sources and the alleviation of poverty. The following measures are implemented: - Identification of farmers interested in grasscutter captive breeding, - Implementation of training courses for farmers on grasscutter rearing, - Delivery of breeding animals, - Supervision of rearing conditions by project staff, - Development of a local extension service for monitoring activities, - Evaluation of structures for grasscutter meat marketing. Results: After identification of key persons for animal rearing training courses were successfully passed and animals were delivered subsequently. Further investigations will evaluate the effects of the grasscutter rearing in the project region. This will be assessed through the - Acceptance of grasscutter rearing by farmers, - Success of the animal caging, - Reproduction rate, - Meat quality, - Marketing success of meat, - Reduction of fire in the vicinity of the timber plantations, - Improvement of peoples livelihood.

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