Página 1 dos resultados de 1431 itens digitais encontrados em 0.013 segundos

Spatial genetic structure of Hymenaea stigonocarpa Mart. ex Hayne assessed with chloroplast microsatellite markers

MORENO, Maria Andreia; TARAZI, Roberto; FERRAZ, Elza Martins; GANDARA, Flavio Bertin; KAGEYAMA, Paulo Yoshio
Fonte: IPEF-INST PESQUISAS ESTUDOS FLORESTAIS Publicador: IPEF-INST PESQUISAS ESTUDOS FLORESTAIS
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
35.86%
The use of chloroplast DNA markers (cpDNA) helps to elucidate questions related to ecology, evolution and genetic structure. The knowledge of inter-and intra-population genetic structure allows to design effective conservation and management strategies for tropical tree species. With the aim to help the conservation of Hymenaea stigonocarpa of the Cerrado (Brazilian savanna) in Sao Paulo State, an analysis of the spatial genetic structure (SGS) was conducted in two populations using five universal chloroplast microsatellite loci (cpSSR). The population of 68 trees of H. stigonocarpa in the Ecological Station of Itirapina (ESI) had a single haplotype, indicating a strong founder effect. In turn, the population of 47 trees of H. stigonocarpa in a contiguous area that includes the Ecological Station of Assis and the Assis State Forest (ESA), showed six haplotypes ((n) over cap (h) = 6) with a moderate haplotype diversity ((h) over cap = 0667 + 0094), revealing that it was founded by a small number of maternal lineages. The SGS analysis for the population ESA/ASF, using Moran`s I index, indicated limited seed dispersal. Considering SGS, for ex situ conservation strategies in the population ESA/ASF, seed harvesting should require a minimum distance of 750 m among seed-trees.

Distribuição das populações de Cladocera (Branchiopoda) nos reservatórios do médio e baixo Tietê: uma análise espacial e temporal; Distribution of Cladocera (Branchiopoda) populations on medium and low Tietê river reservoirs: a spatial and temporal analysis

Zanata, Lucí Helena
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 05/12/2005 PT
Relevância na Pesquisa
35.86%
Reservatórios artificiais são ecossistemas de grande importância econômica e social, porém, alteram as características hidrológicas e ecológicas do meio, interferindo na organização das comunidades bióticas que desempenham papel fundamental na transferência de energia no ecossistema. Nesses ambientes, pode existir uma organização espacial e temporal, tornando diferenciada a composição e distribuição das comunidades. Com o objetivo de verificar essa organização, a comunidade zooplanctônica, com ênfase nas populações de Cladocera, foi avaliada em amostras coletadas nas estações distribuídas no eixo longitudinal dos reservatórios do médio e baixo Tietê (SP), nos meses de fevereiro, maio, julho e outubro de 2000. Os dados obtidos foram relacionados às características ambientais, tais como pH, condutividade, temperatura, oxigênio dissolvido, material em suspensão, nutrientes e clorofila a desse ambiente. Os resultados apontaram para uma diferenciação esperada ao longo do eixo longitudinal do rio Tietê, tanto nas características físicas e químicas, quanto na abundância e distribuição dos organismos. Os reservatórios do médio Tietê estiveram mais eutrofizados do que os reservatórios do baixo Tietê nos períodos analisados...

Redes de comunicação e território: a formação e a organização socioespacial da internet no Brasil; Communication networks and territory: internet's formation and spatial organization in Brazil

Alves, Ludmila Girardi
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 08/11/2013 PT
Relevância na Pesquisa
35.96%
As redes de comunicação por internet são um sistema e uma forma de organização que têm introduzido e modificado padrões de produção preexistentes em espaços de todo o mundo. Este estudo teve o objetivo de analisar as bases materiais e sociais que trouxeram a internet à sua organização atual no território brasileiro, bem como contribuir teoricamente para a relação entre espaço e interações sociais, por meio da aquisição de conhecimento dos objetos que compõem a internet enquanto um conjunto sociotecnico. Apresentamos os conceitos de rede e território em Geografia, bem como suas relações com comunicação, informação e espaço, em referência a autores que têm em comum a abordagem espacial com relevo nos fenômenos sociais engendrados pela comunicação à distância, especialmente Boris Beaude (2008). Sob as categorias de análise formação socioespacial e território usado de Milton Santos (2002), propomos uma periodização da internet no Brasil e caracterizamos a distribuição espacial das redes e acessos à internet no território no período mais recente. Para o aprofundamento da análise espacial, nos apoiamos teoricamente em Jacques Lévy (2003) para o estudo da internet enquanto um fenômeno eminentemente urbano...

Spatial Shaping of Cochlear Innervation by Temporally Regulated Neurotrophin Expression

Fariñas, Isabel; Jones, Kevin R.; Tessarollo, Lino; Vigers, Allison J.; Huang, Eric; Kirstein, Martina; de Caprona, Dominique C.; Coppola, Vincenzo; Backus, Carey; Reichardt, Louis F.; Fritzsch, Bernd
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/08/2001 EN
Relevância na Pesquisa
26.18%
Previous work suggested qualitatively different effects of neurotrophin 3 (NT-3) in cochlear innervation patterning in different null mutants. We now show that all NT-3 null mutants have a similar phenotype and lose all neurons in the basal turn of the cochlea. To understand these longitudinal deficits in neurotrophin mutants, we have compared the development of the deficit in the NT-3 mutant to the spatial–temporal expression patterns of brain-derived neurotrophic factor (BDNF) and NT-3, using lacZ reporters in each gene and with expression of the specific neurotrophin receptors, trkB and trkC. In the NT-3 mutant, almost normal numbers of spiral ganglion neurons form, but fiber outgrowth to the basal turn is eliminated by embryonic day (E) 13.5. Most neurons are lost between E13.5 and E15.5. During the period preceding apoptosis, NT-3 is expressed in supporting cells, whereas BDNF is expressed mainly in hair cells, which become postmitotic in an apical to basal temporal gradient. During the period of neuronal loss, BDNF is absent from the basal cochlea, accounting for the complete loss of basal turn neurons in the NT-3 mutant. The spatial gradients of neuronal loss in these two mutants appear attributable to spatial– temporal gradients of neurotrophin expression. Our immunocytochemical data show equal expression of their receptors...

The Misuse value of space : spatial practices and the production of space in Istanbul

Ozkan, Derya ; Haidu, Rachel
Fonte: University of Rochester Publicador: University of Rochester
Tipo: Tese de Doutorado Formato: Number of Pages:xii, 348 leaves
ENG
Relevância na Pesquisa
35.98%
Thesis (Ph. D.)--University of Rochester. Dept. of Art and Art History, 2008.; This dissertation is an interdisciplinary investigation of the indeterminate political role played by the inhabitants’ spatial practices of misuse in the social production of urban space in contemporary Istanbul. My argument is that both established and emerging hegemonic representations of the city of Istanbul presume a normative definition of the capitalist production of urban space based only on the use and exchange values of space; and they fail to consider what I propose to call “the misuse value of space.” I define the misuse value of space as a potential value that is activated by the spatial practices of misusers. Considering the ways in which the normative definition of the production of space in Istanbul is complicated by the inhabitants of the city through their spatial practices of misuse, I find that the inhabitants are not merely passive consumers of the spaces of the metropolis but they have an active and constitutive role in molding the shape of urban social space. This entails a discussion on spatial authorship, which is normatively supposed to belong to the authorities including urban designers, real estate developers and the state. To show how the spatial practices of misusers are also implicated in the production of space in Istanbul...

Environmental amenities and local development in Australia : spatial hedonic pricing and regional economic models.

Mahmoudi, Parvin
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2012
Relevância na Pesquisa
35.96%
Many Australian cities are under pressure to preserve open spaces and limit suburban sprawl while still providing affordable and desirable housing and encouraging economic growth. In their efforts to preserve open spaces, public policy decision makers, require reliable information on the dollar value of open spaces. Moreover, the Millennium Drought (1997-2009) in regions across Australia, coupled with poor water allocation decisions, has seen a dramatic increase in the share of water diverted to the agricultural and urban sectors, leaving less water to flow into the natural environment. This has led to degradation of wetlands and water-dependent environment in some regions (e.g. Murray Darling Basin (MDB). The present study provides evidence on the local economic role of environmental amenities in urban and rural areas of Australia from two major strands of empirical research, respectively, hedonic pricing and regional economic models. Only economic analyses relying on well-established statistical techniques, reliable and extensive data and well-framed research methodologies can provide evidence about the economic value of environmental amenities. As part of the development of a methodology to estimate the value of environmental amenities in Adelaide...

Automating the administration boundary design process using Hierarchical Spatial Reasoning theory and Geographical Information Systems

Escobar Martínez, Francisco Javier; Eagleson, Serryn; Williamson, Ian
Fonte: Universidade de Alcalá Publicador: Universidade de Alcalá
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
Relevância na Pesquisa
35.94%
This paper addresses the problems associated with the integration of data between incongruent boundary systems. Currently, the majority of spatial boundaries are designed in an uncoordinated manner with individual organisations generating individual boundaries to meet individual needs. As a result, current technologies for analysing geospatial information, such as geographic information systems (GISs), are not reaching their full potential. In response to the problem of uncoordinated boundaries, the authors present an algorithm for the hierarchical structuring of administrative boundaries. This algorithm applies hierarchical spatial reasoning (HSR) theory to the automated structuring of polygons. In turn, these structured boundary systems facilitate accurate data integration and analysis whilst meeting the spatial requirements of selected agencies. The algorithm is presented in two parts. The first part outlines previous research undertaken by the authors into the delineation of administrative boundaries in metropolitan regions. The second part outlines the distinctly different constraints required for administrative-boundary design in rural areas. The formalisation of the algorithm has taken place in a GIS environment utilising Avenue...

Spatial growth and industry age

Desmet, Klaus; Rossi-Hansberg, Esteban
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica Formato: application/pdf
Publicado em //2009 ENG
Relevância na Pesquisa
35.8%
Between 1970 and 2000 employment growth across U.S. counties exhibited very different patterns in manufacturing and services. Whereas manufacturing employment growth was negatively related to initial manufacturing employment across the entire distribution of counties, service employment growth was positively related to initial service employment for intermediate sized counties. This paper presents a theory to rationalize these facts. Local sectoral growth is driven by technological diffusion across space and depends on the age of the sector. The theory correctly predicts the relation between county employment growth and initial county employment in manufacturing at the turn of the 20th century.; Desmet acknowledges the financial support of the Fundación Ramón Areces

Landscape- and field-scale control of spatial variation of soil properties in Mediterranean montane meadows

Rey Benayas, José María; García Sánchez-Colomer, Manuel; Escudero, Adrián
Fonte: Kluwer Academic Publishers Publicador: Kluwer Academic Publishers
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/acceptedVersion Formato: application/pdf
ENG
Relevância na Pesquisa
35.9%
Soil properties of terrestrial ecosystems are controlled by a variety of factors that operate at different scales. We tested the role of abiotic and biotic factors that potentially influence spatial gradients of total ion content, acidity, carbon, total nitrogen, and total phosphorous in topsoil. We studied a network of Mediterranean montane meadows that spans a 2000-m altitudinal gradient. The analyzed factors were grouped into two spatial scales: a landscape scale (climate and land form) and a field scale (topography, soil texture, soil moisture, and plant community composition). Total ion content and acidity are the major and independent variation trends of soil geochemistry. Soil acidity, carbon, and nitrogen increased along the altitudinal gradient whereas there was no relationship between total ion content and phosphorous and elevation. Climate had no direct influence on the analyzed gradients; all effects of climate were indirect through plant community composition and/or soil moisture. The results point to three types of models that explain the gradients of soil chemical composition: (1) a predominantly biotic control of carbon and nitrogen, (2) a predominantly abiotic control of acidity, and (3) a combined biotic and abiotic control of total ionic content. No direct or indirect effects explained the gradient of phosphorous. In our study region (central Spain)...

Users as essential contributors to spatial cyberinfrastructures

Poore, Barbara S.
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
35.94%
Current accounts of spatial cyberinfrastructure development tend to overemphasize technologies to the neglect of critical social and cultural issues on which adoption depends. Spatial cyberinfrastructures will have a higher chance of success if users of many types, including nonprofessionals, are made central to the development process. Recent studies in the history of infrastructures reveal key turning points and issues that should be considered in the development of spatial cyberinfrastructure projects. These studies highlight the importance of adopting qualitative research methods to learn how users work with data and digital tools, and how user communities form. The author's empirical research on data sharing networks in the Pacific Northwest salmon crisis at the turn of the 21st century demonstrates that ordinary citizens can contribute critical local knowledge to global databases and should be considered in the design and construction of spatial cyberinfrastructures.

Turn around to have a look? Spatial referencing in dorsal vs. frontal settings in cross-linguistic comparison

Beller, Sieghard; Singmann, Henrik; Hüther, Lisa; Bender, Andrea
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Publicado em 02/09/2015 EN
Relevância na Pesquisa
26.21%
When referring to an object in relation to another, speakers of many languages can adopt a relative frame of reference (FoR). Following Levinson (2003), this kind of FoR can be established by projecting an observer's perspective onto the ground object either by translation, reflection, or rotation. So far, research on spatial FoRs has largely ignored the extent of variation in which of these projections are preferred generally, and specifically what kind of FoR is established for spatial arrays in one's back. This may seem justified by assumptions on “natural” preferences: for reflection in frontal settings (Canonical Encounter Hypothesis), and for converting dorsal into frontal situations by a turn of the observer before a reference is made (Turn Hypothesis). We scrutinize these assumptions by comparing the FoRs adopted for small-scale, static spatial arrays by speakers of four languages (German, US-English, Mandarin Chinese, and Tongan). Addressing the problem of inherent ambiguities on the item level when assessing FoRs from spatial prepositions, we use a multinomial processing tree (MPT) model for estimating probabilities of referencing strategies across sets of items. Substantial differences in frontal settings, both between and within languages...

Aprendizaje espacial en el anfibio anuro Bufo arenarum. Estrategias, fenómenos y bases neurales; Spatial learning in the anuran amphibian Bufo arenarum. Strategies, phenomena and neural basis

Daneri, María Florencia
Fonte: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires Publicador: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires
Tipo: info:eu-repo/semantics/doctoralThesis; tesis doctoral; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2010 SPA
Relevância na Pesquisa
36.06%
La presente tesis es un estudio de las estrategias, los fenómenos y las bases neurales del aprendizaje espacial en el sapo común Bufo arenarum. El análisis de las estrategias de aprendizaje espacial demuestra que estos animales son capaces de orientarse utilizando tanto una estrategia de guía (mediante el uso de claves visuales ambientales) como una estrategia de giro (tomando como referencia su propio cuerpo). Además, que esta última estrategia es la predominante si las claves ambientales brindan información contradictoria. También se pudo determinar la presencia de cuatro fenómenos del aprendizaje: el efecto de la distancia de la clave visual al refuerzo, el bloqueo y el ensombrecimiento entre claves y la inhibición latente. Estos fenómenos fueron ampliamente descriptos en otras clases de vertebrados, y por primera vez observados en anfibios en este trabajo. Al explorar las bases neurales de este tipo de aprendizaje, se pudo establecer el papel fundamental del pallium medial (área homóloga al hipocampo) para la orientación en el espacio, tanto mediante el uso de claves visuales como mediante el uso de la estrategia de giro. Estos resultados revelan que el hipocampo de los mamíferos y el pallium medial de los anfibios no tienen una equivalencia funcional completa.; This thesis is a study of the strategies...

Variabilidad espacial y temporal de la concentración del hielo marino antártico y su relación con la circulación atmosférica; Antartic sea ice concentration spatial and temporal variability and its relationship with atmospheric circulation

Barreira, Sandra C. B.
Fonte: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires Publicador: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires
Tipo: info:eu-repo/semantics/doctoralThesis; tesis doctoral; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2008 SPA
Relevância na Pesquisa
35.86%
Existen numerosos estudios en la literatura que sugieren algún tipo de conexión entre los campos de hielo marino de las regiones polares y el clima global pero, la naturaleza específica y los mecanismos a través de los cuales las variaciones en los campos de hielo marino están relacionadas con el clima global o de latitudes medias están todavía pobremente definidos. La presente tesis pretende completar los estudios realizados previamente por otros autores y mejorar los conocimientos existentes sobre conexiones entre el hielo marino en la Antártida y el clima global, a la vez que evaluar su significado enfocándose en la región antártica donde se producen las mayores variaciones del campo de hielo marino, tanto temporal como espacialmente, que es sobre los mares de Amundsen, Bellingshausen y Weddell. Específicamente, lo que se intentó realizar fue cuantificar la variabilidad tanto espacial como temporal del campo de hielo marino, identificar las relaciones que existen entre la variabilidad del hielo marino y el clima tanto polar, de latitudes medias como global, señalar la significancia de estas relaciones e identificar regiones geográficas que puedan mostrar las conexiones más fuertes, teniendo en cuenta que la identificación de las conexiones entre la región polar y el resto de las regiones terrestres es el primer paso para determinar los mecanismos responsables de las mismas. Para examinar las variaciones espaciales del hielo marino antártico...

¿Nuevas geografías culturales?

Jackson, Peter
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: info:eu-repo/semantics/review; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //1999 CAT
Relevância na Pesquisa
36.05%
Este artículo da cuenta de las nuevas direcciones tomadas en el seno de la geografía humana a consecuencia del «giro cultural». Ofrece, además, una breve cronología de hechos recientes, emprende una caracterización del «giro cultural» y evalúa hasta qué punto se ha producido un «giro espacial» concomitante en los estudios culturales. Los críticos sostienen que, por centrarse en cuestiones de representación, cultura y significado, se ha dejado a un lado el interés preferente por las desigualdades materiales dentro de la sociedad. El artículo concluye con algunas reflexiones acerca de las direcciones futuras a tomar dentro de la geografía cultural, y en concreto en relación con los procesos de consumo y mercantilización, en los que existe la posibilidad de trascender los límites entre «lo económico» y «lo cultural».; Aquest article presenta les noves direccions adoptades en el marc de la geografia humana com a conseqüència del «gir cultural». Ofereix, a més, una breu cronologia de fets recents, enceta una caracterització del gir cultural i avalua fins a quin punt s'ha produït un «gir espacial» concomitant en els estudis culturals. Els crítics sostenen que, pel fet de centrar-se en qüestions de representació...

Pensar topográficamente : lugar, espacio y geografía

Malpas, Jeff
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Artigo de Revista Científica Formato: application/pdf
Publicado em //2015 SPA
Relevância na Pesquisa
46%
El texto parte de la consideración de una serie de problemas relacionados con la manera en que se ha producido el denominado «giro espacial» en distintas disciplinas sociales, con el fin de reivindicar una forma de pensamiento topográfico que asuma el lugar como centro de compresión de lo humano. Para ello, se presentan una serie de nociones básicas (como las de límite, determinación o crítica) que articulan el marco dentro del cual los conceptos de espacio, lugar y tiempo pueden definirse ontológicamente y que ofrecen una manera de reflexionar sobre el lugar de lo humano, que es, a la vez, una reflexión sobre el propio lugar del pensamiento.; El text parteix de la consideració d’una sèrie de problemes relacionats amb la manera com s’ha produït l’anomenat «gir espacial» en diferents disciplines socials, per tal de reivindicar una forma de pensament topogràfic que assumeixi el lloc com a centre de compressió del que és humà. Amb aquesta finalitat, s’hi presenten una sèrie de nocions bàsiques (com ara les de límit, determinació o crítica) que articulen el marc dins del qual els conceptes d’espai, lloc i temps es poden definir ontològicament i que ofereixen una manera de reflexionar sobre el lloc d’allò que és humà...

Auxiliary variables for the mapping of the drainage network: spatial correlation between relieve units, lithotypes and springs in Benevente River basin-ES; Variáveis auxiliares para o mapeamento da rede de drenagem: correlação espacial entre nascentes, unidades de relevo e litotipos na bacia hidrográfica do rio Benevente-ES

Sampaio, Tony Vinicius Moreira; Augustin, Cristina Helena Ribeiro Rocha
Fonte: Programa de Pós-Graduação em Geografia Humana. Universidade de São Paulo. Publicador: Programa de Pós-Graduação em Geografia Humana. Universidade de São Paulo.
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 12/12/2014 POR
Relevância na Pesquisa
35.9%
Process of the drainage network mapping present methodological limitations re- sulting in inaccurate maps, restricting their use in environmental studies. Such problems demand the realization of long field surveys to verify the error and the search for auxiliary variables to optimize this works and turn possible the analysis of map accuracy. This research aims at the measurement of the correlation be- tween springs, lithotypes and relieve units, characterized by Roughness Concentration Index (RCI) in River Basin Benevente-ES, focusing on the operations of map algebra and the use of spatial statistical techniques. These procedures have identified classes of RCI and lithotypes that present the highest and the lowest correlation with the spatial distribution of springs, indicating its potential use as auxiliary variables to verify the map accuracy.; Processos de mapeamento da rede de drenagem têm limitações metodológicas que resultam em imprecisões e restringem seu uso em estudos ambientais. Tais problemas demandam extensos levantamentos de campo e a busca de variáveis auxiliares que otimizem esses trabalhos, permitindo a análise da acurácia dos ma- pas produzidos. Esta pesquisa mediu a correlação entre nascentes, litotipos e uni- dades de revelo...

After the spatial turn: for a sociology of space; O spatial turn: para uma sociologia do espaço

Löw, Martina
Fonte: Universidade de São Paulo. Faculdade de Filosofia, Letras e Ciências Humanas Publicador: Universidade de São Paulo. Faculdade de Filosofia, Letras e Ciências Humanas
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; Formato: application/pdf
Publicado em 01/11/2013 POR
Relevância na Pesquisa
36%
The aim of this article is to lend plausibility to the sociological concept of space as a relational disposition of beings and goods. Since globalization processes also interfere in people's ways of experiencing space, Sociology has been forced to rethink its conceptualizations. In methodological terms, I juxtapose two contrary positions: materialist theorems that set out from spatial structure, and practice-oriented approaches that set out from action. Citing Anthony Giddens's theory of structuration, I conclude by proposing a synthesis of these two approaches. This allows us to develop a theory of space that neither attributes it with essentialist forces, nor reduces it to a mere sequence of actions.; Este artigo tem como objetivo conferir plausibilidade ao conceito sociológico do espaço como disposição relacional de seres e bens. Como os processos da globalização também interferem nos modos de vivenciar o espaço, a Sociologia vê-se obrigada a repensar sua conceituação. Em termos metodológicos, oporemos duas posições contrárias: teoremas materialistas que partem da estrutura espacial, de um lado, e abordagens orientadas na prática e que partem da ação, de outro. Como conclusão, com referência à teoria da estruturação de Anthony Giddens...

Analysis of tailing pond contamination in Galicia using generalized linear spatial models

Taboada,Javier; Saavedra,Ángeles; Paz,María; Bastante,Fernando G.; Alejano,Leandro R.
Fonte: DYNA Publicador: DYNA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2015 EN
Relevância na Pesquisa
35.94%
We statistically analysed the chemical components present in waste water from mines in Galicia (NW Spain). These elements pose a risk to public health and the environment, most particularly in the event of a failure in the containment structure of a pond or dam. The statistical processing of the data, which started with an analysis of the typical contaminants present in mining ponds and dams, pointed to the potential limitations of using non-spatial models for spatially structured data. Our results indicate the greater potential of the generalized linear spatial model over the generalized linear model for analysis of spatially structured data. We also show how a misspecification of the model for analysing spatial data can lead to misleading conclusions, which might lead, in turn, to poorly designed protective or corrective measures.

Geostatistical modeling of clay spatial distribution in siliciclastic rock samples using the plurigaussian simulation method

Méndez-Venegas,Javier; Díaz-Viera,Martín A.
Fonte: Instituto de Geofísica, UNAM Publicador: Instituto de Geofísica, UNAM
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2013 EN
Relevância na Pesquisa
36.08%
In order to implement secondary and enhanced oil recovery processes in complex terrigenous formations as is usual in turbidite deposits, a precise knowledge of the spatial distribution of shale grains is a crucial element for the fluid flow prediction. The reason of this is that the interaction of water with shale grains can significantly modify their size and/or shape, which in turn would cause porous space sealing with the subsequent impact in the flow. In this work, a methodology for stochastic simulations of spatial grains distributions obtained from scanning electron microscopy images of siliciclastic rock samples is proposed. The aim of the methodology is to obtain stochastic models would let us investigate the shale grain behavior under various physico-chemical interactions and flux regimes, which in turn, will help us get effective petrophysical properties (porosity and permeability) at core scale. For stochastic spatial grains simulations a plurigaussian method is applied, which is based on the truncation of several standard Gaussian random functions. This approach is very flexible, since it allows to simultaneously manage the proportions of each grain category in a very general manner and to rigorously handle their spatial dependency relationships in the case of two or more grain categories. The obtained results show that the stochastically simulated porous media using the plurigaussian method adequately reproduces the proportions...

Spatial practices in Lowliebenhof: the case of Maphango v Aengus Lifestyle Properties (Pty) Ltd

de Villiers,I
Fonte: PER: Potchefstroomse Elektroniese Regsblad Publicador: PER: Potchefstroomse Elektroniese Regsblad
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2014 EN
Relevância na Pesquisa
36%
In Maphango v Aengus Lifestyle Properties (Pty) Ltd 2012 5 BCLR 449 (CC) the question before the Constitutional Court was when a landlord may legally cancel contracts of lease and evict tenants. In answering this question the court had to consider the constitutional protection against arbitrary evictions in section 26(3) and the provisions of the Rental Housing Act 50 of 1999. The applicants sought a declaratory order that the landlord had terminated their leases unlawfully, because the termination had been intended to double (and in some instances more than double) the rent. The applicants argued that this escalation violated contractual and legislative provisions governing the procedure and conditions under which a landlord can increase the amount of a rental. The Constitutional Court found in favour of the tenants and postponed the appeal to allow any of the parties to lodge a complaint at the Gauteng Rental Housing Tribunal. The narrow focus of this note is the manner in which the Constitutional Court in the Maphango case interpreted the concept of "practice" in the Rental Housing Act and how this in turn corresponds to perceptions of urban spaces. The inquiry is informed by the spatial justice turn and relies on the works of Michel de Certeau...