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Ecological systems theory, also called development in context or human ecology theory, identifies five environmental systems with which an individual interacts. This theory provides the framework from which community psychologists study the relationships with individuals' contexts within communities and the wider society. Ecological systems theory was developed by Urie Bronfenbrenner. Wikipedia.

Nevidimova O.,Ecological Systems
11th International Multidisciplinary Scientific Geoconference and EXPO - Modern Management of Mine Producing, Geology and Environmental Protection, SGEM 2011 | Year: 2011

In the article is shown the approach to a research on hydropower resources in Western Siberia. The hydropower potential estimates are based on the following factors: water content of rivers, river slopes and flow velocities. Identified are the portions of rivers with largest energy capacity and the possibility to use hydro potential. A measure of hydrological tension was calculated, which takes into account the quantitative characteristics of following factors: low water, ice effects, high water, sediments runoff (amount of transported sediment), snowmelt runoff intensity. Based on these calculations, the territory was ranked by the degree of hydrological hazards. © SGEM2011 All Rights Reserved by the International Multidisciplinary Scientific GeoConference SGEM. Source

Hellweg S.,Ecological Systems | Canals L.M.I.,Sustainable Consumption and Production
Science | Year: 2014

In the modern economy, international value chains - production, use, and disposal of goods - have global environmental impacts. Life Cycle Assessment (LCA) aims to track these impacts and assess them from a systems perspective, identifying strategies for improvement without burden shifting. We review recent developments in LCA, including existing and emerging applications aimed at supporting environmentally informed decisions in policy-making, product development and procurement, and consumer choices. LCA constitutes a viable screening tool that can pinpoint environmental hotspots in complex value chains, but we also caution that completeness in scope comes at the price of simplifications and uncertainties. Future advances of LCA in enhancing regional detail and accuracy as well as broadening the assessment to economic and social aspects will make it more relevant for producers and consumers alike. Source

Palenzuela J.,CSIC - Experimental Station of El Zaidin | Barea J.-M.,CSIC - Experimental Station of El Zaidin | Ferrol N.,CSIC - Experimental Station of El Zaidin | Oehl F.,Ecological Systems
Mycologia | Year: 2011

A new dimorphic fungal species in the arbuscular mycorrhiza-forming Glomeromycota, Ambispora granatensis, was isolated from an agricultural site in the province of Granada (Andalucý́a, Spain) growing in the rhizosphere of Asparagus officinalis. It was propagated in pot cultures with Trifolium pratense and Sorghum vulgare. The fungus also colonized Ri TDNA transformed Daucus carota roots but did not form spores in these root organ cultures. The spores of the acaulosporoid morph are 90-150 mm diam and hyaline to white to pale yellow. They have three walls and a papillae-like rough irregular surface on the outer surface of the outer wall. The irregular surface might become difficult to detect within a few hours in lactic acid-based mountings but are clearly visible in water. The structural central wall layer of the outer wall is only 0.8-1.5 μm thick. The glomoid spores are formed singly or in small, loose spore clusters of 2-10 spores. They are hyaline to pale yellow, (25)40-70 mm diam and have a bilayered spore wall without ornamentation. Nearly full length sequences of the 18S and the ITS regions of the ribosomal gene place the new fungus in a separate clade next to Ambispora fennica and Ambispora gerdemannii. The acaulosporoid spores of the new fungus can be distinguished easily from all other spores in genus Ambispora by the conspicuous thin outer wall. © 2011 by The Mycological Society of America. Source

Okunev A.O.,Novgorod State University | Verozubova G.A.,Ecological Systems
Journal of Applied Crystallography | Year: 2015

X-ray topography images in the form of contrast rosettes from edge dislocations of the slip system in ZnGeP2 single crystals, obtained under different diffraction conditions, are identified and interpreted. To analyze and model the dislocation images, a semi-phenomenological theory of contrast is applied. The simulation of images of edge dislocations under Borrmann effect conditions was carried out in cases when the diffraction vector was parallel or perpendicular to the slip plane of the dislocation. In both cases, the main part of the experimental image is formed because of waveguiding of Bloch waves in the regions of tension and compression of the lattice on either side of the slip plane. Additional image details arise through relaxation of stresses at the exit surface. Since the color of all lobes of the contrast rosette is related to the sign of the deformation, the location of the dislocation half-plane is unambiguously determined. Thus, from the form of the rosette image, it is possible to obtain the slip plane, the magnitude and sign of the Burger's vector, and the direction of the dislocation line. © International Union of Crystallography 2015. Source

Kazinski P.O.,Tomsk State University | Shipulya M.A.,Ecological Systems
Annals of Physics | Year: 2011

Rapidly convergent expansions of a one-loop contribution to the partition function of quantum fields with ellipsoid constant-energy surface dispersion law are derived. The omega-potential is naturally decomposed into three parts: the quasiclassical contribution, the contribution from the branch cut of the dispersion law, and the oscillating part. The low- and high-temperature expansions of the quasiclassical part are obtained. An explicit expression and a relation of the contribution from the cut with the Casimir term and vacuum energy are established. The oscillating part is represented in the form of the Chowla-Selberg expansion of the Epstein zeta function. Various resummations of this expansion are considered. The general procedure developed is then applied to two models: massless particles in a box both at zero and nonzero chemical potential, and electrons in a thin metal film. Rapidly convergent expansions of the partition function and average particle number are obtained for these models. In particular, the oscillations of the chemical potential of conduction electrons in graphene and a thin metal film due to a variation of size of the crystal are described. © 2011 Elsevier Inc. Source

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