Search results for "GRAS"
showing 10 items of 727 documents
The quantum chiral Minkowski and conformal superspaces
2010
We give a quantum deformation of the chiral super Minkowski space in four dimensions as the big cell inside a quantum super Grassmannian. The quantization is performed in such way that the actions of the Poincar\'e and conformal quantum supergroups on the quantum Minkowski and quantum conformal superspaces are presented.
Teaching energy conservation as a unifying principle in physics
2009
In this work we present the design and assessment of a teaching sequence aimed at introducing the principle of energy conservation at post-compulsory secondary school level (16-18 year olds). The proposal is based on the result of research into teaching-learning difficulties and on the analysis of the physics framework. Evidence is shown that this teaching sequence, together with the methodology used in the classroom, may result in students having a better grasp of the principle of energy conservation. Keywords Physics education · Energy conceptions · Teaching activities
The Lygeo-Stipetea class in Sicily
2009
Long-term soil feedback on plant N allocation in defoliated grassland miniecosystems
2005
Abstract Defoliation of plants is known to have effects on soil organisms and nutrient availability in grassland communities, but few studies have examined whether changes in soil attributes can further feed back to plant growth and plant nutrient content. To examine defoliation-induced soil feedbacks, we established replicated miniecosystems with a grass Phleum pratense , defoliated half of the systems, collected soil from both defoliated and non-defoliated systems and planted new seedlings into each soil. The two soils did not differ in promoting shoot and root growth. However, seedlings that grew in the soil collected from defoliated systems had higher shoot N content, allocated relative…
Effetti della dieta sul profilo acidico del latte di capre con diverso genotipo per l’αs1-CN.
2013
An Interview with Giorgio Grassi
2007
In January 2007, Lucia Tozzi visited Giorgio Grassi's office in Milan. Their conversation touched on Grassi's recent work on Leon Battista Alberti, which is examined here in the context of Grassi's obliquely expressed views on contemporary architecture and the cult of personality. As perhaps the most intellectually rigorous and formally consistent Rationalist architect of his generation, Grassi's work and thinking retain a hermetic aspect, but one notable for its philosophical self-questioning and underlying political commitment. Copyright © 2007 John Wiley & Sons, Ltd.
Short-term low-severity spring grassland fire impacts on soil extractable elements and soil ratios in Lithuania
2017
Abstract Spring grassland fires are common in boreal areas as a consequence of slash and burn agriculture used to remove dry grass to increase soil nutrient properties and crop production. However, few works have investigated fire impacts on these grassland ecosystems, especially in the immediate period after the fire. The objective of this work was to study the short-term impacts of a spring grassland fire in Lithuania. Four days after the fire we established a 400 m2 sampling grid within the burned area and in an adjacent unburned area with the same topographical, hydrological and pedological characteristics. We collected topsoil samples immediately after the fire (0 months), 2, 5, 7 and …
Seasonal dynamics of Posidonia oceanica beach-cast wracks in a Sicilian beach: an overlooked system for carbon dynamics
2019
Seagrass detritus accumulates along the coasts forming beach-cast wracks. Being subject to environmental gradients and hydrodynamism, the size and composition of beach-cast wracks may vary in space and time. Also the composition may vary depending on both proximities to and productivity of the adjacent seagrass meadows. Despite their dynamic nature, seagrass beach-casts provide important ecosystem services, by contributing to the nutrient and carbon flow between marine and terrestrial systems, supporting beach biodiversity and trophic webs and protecting the coastline from erosion. However, the knowledge about beach-cast dynamics, ecological role and functions is still fragmented and deserv…
The use of very high resolution images for the estimation of Posidonia oceanica beach-cast morphology
2019
Posidonia oceanica is an endemic Mediterranean seagrass that forms wide and dense meadows from the surface to depths of about 40 m. During fall and winter, due to aging and storms, leaves and rhizomes break away from the seagrass meadows and accumulate on the shores (from a few centimeters in the water to several meters inshore) forming conspicuous beach-casts of P. oceanica detritus. These structures have received increasing attention in the last decade for the potential ecosystem services they provide in protecting the coast from erosion, linking marine and terrestrial food chains and contributing to carbon and nutrients fluxes. However, seagrass beach-cast morphology is not easy to estim…