G-structures of second order defined by linear operators satisfying algebraic relations

The present work is based on a type of structures on a differential manifold V , called G-structures of the second kind, defined by endomorphism J on the second order tangent bundle T2(V ). Our objective is to give conditions for a differential manifold to admit a real almost product and a generalised almost tangent structur

G-structures of second order defined by linear operators satisfying algebraic relations

The present work is based on a type of structures on a differential manifold V , called G-structures of the second kind, defined by endomorphism J on the second order tangent bundle T2(V ). Our objective is to give conditions for a differential manifold to admit a real almost product and a generalised almost tangent structur

The Europeanisation of the Balkans (EU membership aspiration and institutional adaptation in the Balkan countries)

SIGLEAvailable from British Library Document Supply Centre-DSC:DXN043938 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Land application of biosolids: benefits, risks and cost

Summarization: Governmental agencies, municipalities and industries around the world have been seeking viable alternatives for disposing of biosolids generated from wastewater treatment since landfill capacity diminishes and waste disposal costs increase. Biosolids are composed of compounds valuable for agricultural use (organic matter, nitrogen, phosphorous, potassium and micro-nutrients such as calcium, sulphur and magnesium), and pollutants that include heavy metals, organic compounds and pathogens. While they can be a valuable resource, potential risks associated with the nutrients, disease causing microorganisms, chemical contaminants and unstabilized material that biosolids include need to be appropriately managed. Alternative disposal methods for biosolids that have been used in the past include dumping at sea, landfilling, incineration and land application. The amount of generated sludge that needs to be disposed of in EU is exceeding 10 M dry tons per year while the US has to dispose approximately 7 M dry tons per year. Given that approximately half of the operating cost of waste water treatment plants is related to the treatment and disposal of sludge, the magnitude of treatment and disposal has promoted regulatory actions during the past 20 years focusing mostly on land application of biosolids and spurred the development of composting and other lower cost technologies that ensure not only their disposal, but also their reuse. The objective of this manuscript is to provide an overview of the potential benefits and risks of land application of biosolids with special emphasis on rural environments as well as on the management cost of disposal. Special focus will be given to sludges produced in rural areas such as the island of Crete and on closing the nutrient loop between urban and peri-urban areas. Sewage sludge has to be treated (dewatered and stabilized) before land application either in terms of soil fertilization or land reclamation. There are several treatment methods available: lime stabilization, composting, anaerobic digestion and thermal drying. Land application of biosolids has significantly positive effect on soil fertility ensuring their use in a sustainable manner. Their relatively high and readily available nutrient content has high fertilization value for the plants. In addition to the high nutritional value, biosolids improve the physico-chemical properties of the soil (soil conditioning) by increasing soil organic matter, decrease bulk density, increase soil particle aggregation, soil structure and porosity. Organic matter addition stimulates microbial activity and enzymatic production in the soil that are essential biocatalyst for plant growth. Finally, sludge amendments to agricultural lands have increased crop production and yields typically exceed inorganic fertilization yields. The risk associated with land application of biosolids depends on the origin of the pollution loads entering the waste water treatment plants (municipal versus industrial loads). Human and animal health, soil quality, plant growth and water quality can be seriously affected by uncontrolled pollutants and pathogens and excessive or improperly application of N and P that may be contained in biosolids. Excessive rates of land application can negatively impact groundwater quality because of nutrient leaching. However, this risk is substantially reduced if appropriate stabilization methods have been applied and risk bazed, site-specific land application loads have been incorporated in current regulations. This would be especially true in rural areas where the quality of sludges is of superior quality compared to major urban centres that have significant industrial contributions. The cost of treatment (both capital cost and operating cost) can be significantly reduced if we view sludge treatment and disposal as part of a holistic system of separation and recycling of organic matter from all sources (including solid waste -organic fraction recycling, agricultural wastes, livestock etc) in a urban-peri urban system and in this way closing the nutrient loop and returning the organic matter back to the cultivated soil, restoring in this way soil fertility.Παρουσιάστηκε στο: International Water Association, Wastewater Purification and Reus

Europeanizing the Balkans: rethinking the post-communist and post-conflict transition

This paper argues that the post-communist and post-conflict transition of the Balkans requires a methodological shift in line with globalization, which shapes political and economic transformation from within through transnational networks. As a specially tailored mechanism leading to the accession of the Balkans into the European Union, the Stabilization and Association Process (SAp) sets the framework for political and economic transformation of the region. The paper posits that the weakness of the EU's approach derives from the fact that it is informed by the dominant transition paradigm, which marginalizes the impact of globalization, and specifically the role of transnational actors. The paper provides a critique of the transition literature and its explanatory potential to account for the post-conflict and post-communist transition in the Balkans. It goes on to examine the Balkan transnational space and the role of transnational actors in the process of transition as an important additional explanation, while taking into account a double legacy: the domestic legacy, inherited from communism, and the transnational and post-communist legacy acquired during the conflict. It advances an argument that a weak state offers us a conceptual nexus for the study of democratic transition in the Balkans in the global age. We demonstrate that transnational networks benefit from a weak state and perpetuate the very weakness that sustains them. At the same time, these networks exploit multi-ethnicity and stir ethnic tensions, lest stabilization should limit their scope for action. As a result, state- and nation building appear as mutually enfeebling rather than reinforcing, thus subverting the existing EU mechanisms

Water Management Across Borders, Scales and Sectors: Recent developments and future challenges in water policy analysis

Integrated water resource management (IWRM) is widely accepted and has been implemented though international, national and regional water management guidelines. Nonetheless, concrete implementation of IWRM gives rise to new questions for policy analysis. Scholars interested in water regulation, the design of effective and efficient policy instruments, and structures of participative and multi-level policy processes face challenges regarding research design, concepts and empirical approaches. This special issue integrates research about regional, national and transboundary policy perspectives on water management in seven countries, four continents and two transnational water bodies. From the six articles presented in this special issue, we learn more about how to define integration, to think about borders and scales and to theoretically and empirically study collaborative management in water policy analysis