990 resultados para land art


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Eucalyptus savannas on low nutrient soils are being extensively cleared in Queensland. In this paper we provide background information relevant to understanding nutrient (particularly nitrogen) dynamics in sub/tropical savanna, and review the available evidence relevant to understanding the potential impact of clearing Eucalyptus savanna on nutrient relations. The limited evidence presently available can be used to argue for the extreme positions that: (i) woody vegetation competes with grasses Cor resources. and tree/shrub clearing improves pasture production, (ii) woody vegetation benefits pasture production. At present, the lack of fundamental knowledge about Australian savanna nutrient relations makes accurate predictions about medium- and long-term effects of clearing on nutrient relations in low nutrient savannas difficult. The future of cleared savannas will differ if herbaceous species maintain all functions that woody vegetation has previously held, or if woody species have functions distinct from those of herbaceous vegetation. Research suggests that savanna soils are susceptible to nitrate leaching, and that trees improve the nutrient status of savanna soils in some situations. The nitrogen capital of cleared savanna is at risk if mobile ions are not captured efficiently by the vegetation. and nitrogen input via N-2 fixation from vegetation and microbiotic crusts is reduced. In order to predict clearing effects on savanna nutrient relations, research should be directed to answering (i) how open or closed nutrient cycles are in natural and cleared savanna, (ii) which functions are performed by savanna constituents such as woody and herbaceous vegetation, native and exotic plant species. termites, and microbiotic 7 crusts in relation to nutrient cycles. In the absence of detailed knowledge about savanna functioning, clearing carries the risk of promoting continuous nutrient depiction.

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The relationship between evidence-based medicine (EBM) and clinical judgement is the subject of conceptual and practical dispute. For example, EBM and clinical guidelines are seen to increasingly dominate medical decision-making at the expense of other, human elements, and to threaten the art of medicine. Clinical wisdom always remains open to question. We want to know why particular beliefs are held, and the epistemological status of claims based in wisdom or experience. The paper critically appraises a number of claims and distinctions, and attempts to clarify the connections between EBM, clinical experience and judgement, and the objective and evaluative categories of medicine. I conclude that to demystify clinical wisdom is not to devalue it. EBM ought not be conceived as needing to be limited or balanced by clinical wisdom, since if its language is translatable into terms comprehensible and applicable to individuals, it helps constitute clinical wisdom. Failure to appreciate this constitutive relation will help perpetuate medical paternalism and delay the adoption of properly evidence-based practice, which would be both unethical and unwise.

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This paper addresses robust model-order reduction of a high dimensional nonlinear partial differential equation (PDE) model of a complex biological process. Based on a nonlinear, distributed parameter model of the same process which was validated against experimental data of an existing, pilot-scale BNR activated sludge plant, we developed a state-space model with 154 state variables in this work. A general algorithm for robustly reducing the nonlinear PDE model is presented and based on an investigation of five state-of-the-art model-order reduction techniques, we are able to reduce the original model to a model with only 30 states without incurring pronounced modelling errors. The Singular perturbation approximation balanced truncating technique is found to give the lowest modelling errors in low frequency ranges and hence is deemed most suitable for controller design and other real-time applications. (C) 2002 Elsevier Science Ltd. All rights reserved.

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The influence of change in land-use from native vegetation to pasture (20-71 yr after conversion), and subsequent change from pasture to eucalypt plantation (7-10 yr after conversion) on soil organic matter quality was investigated using C-13 CP/MAS NMR spectroscopy. We studied surface soil (0-10 cm) from six sites representing a range of soil, and climate types from south-western Australia. Total C in the samples ranged from 1.6 to 5.5%, but the relative proportions of the four primary spectral regions (alkyl, O-alkyl, aromatic and carboxylic) were similar across the sites, and changes due to land-use at each site were relatively minor. Main impacts of changed land-use were higher O-alkyl (carbohydrate) material under pasture than under native vegetation and plantation (P = 0.048), and lower aromatic C under pasture than under native vegetation (P = 0.027). The decrease in aromatic C in pasture soils was related to time since clearing. (C) 2002 Elsevier Science Ltd. All rights reserved.

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Science communication. including extension services. plays a key role in achieving sustainable native vegetation management. One of the pivotal aspects of the debate on sustainable vegetation management is the scientific information underpinning policy-making. In recent years. extension services have Shifted their focus from top-down technology transfer to bottom-up participation and empowerment. I here has also been a broadening of communication strategies to recognise the range of stakeholders involved in native vegetation management and to encompass environmental concerns. This paper examines the differences between government approaches to extension services to deliver policy and the need for effective communication to address broader science issues that underpin native vegetation management. The importance of knowing the learning styles of the stakeholders involved in native vegetation management is discussed at a time of increasing reliance on mass communication for information exchange and the importance of personal communication to achieve on-ground sustainable management. Critical factors for effective science-management communication are identified Such as: (i) undertaking scientific studies (research) with community involvement, acceptance and agreed understanding of project objectives (ii) realistic community consultation periods: (iii) matching communication channels with stakeholder needs; (iv) combining scientific with local knowledge in in holistic (biophysical and social) approach to understanding in issued and (v) regional partnerships. These communication factors are considered to be essential to implementing on-ground natural resource management strategics and actions, including those concerned with native vegetation management.

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O controle de ag??ncias de defesa da concorr??ncia sobre a estrutura dos mercados constitui pr??tica comum em pa??ses maduros e vem ganhando import??ncia crescente em economias emergentes. Tal atividade envolve exame de atos de concentra????o econ??mica tais como fus??es, aquisi????es, joint ventures ou incorpora????es. No Brasil este tipo de controle ?? recente, tendo sido institu??do pela Lei n?? 8.884, de junho de 1994. Desde ent??o, o Conselho Administrativo de Defesa da Concorr??ncia - CADE julgou 29 (vinte e nove) atos de concentra????o, em contraste com a experi??ncia secular de pa??ses como EUA, Canad?? e Austr??lia e de v??rias d??cadas nas na????es europ??ias depois da Segunda Guerra. A exemplo de v??rias outras ??reas de pol??tica p??blica, tornou-se imperativo agilizar os ??rg??os de defesa da concorr??ncia. Isto decorre, entre outros fatores, do intenso processo de reestrutura????o produtiva em curso no pa??s associados ?? desestatiza????o e abertura da economia. Diante das circunst??ncias descritas, ?? preciso assegurar agilidade, transpar??ncia, excel??ncia t??cnica no processo decis??rio e estabilidade de regras, todos ingredientes indispens??veis para gerar seguran??a jur??dica. Esta ??ltima, por seu turno, diminui o risco do investimento, estimulando invers??es, produ????o e emprego. Nesse sentido, o CADE promoveu mudan??as importantes no procedimento de an??lise de atos de concentra????o em colabora????o com a Secretaria de Direito Econ??mico do Minist??rio da Justi??a (SDE) e a Secretaria de Acompanhamento Econ??mico do Minist??rio da Fazenda (SEAE) mediante a edi????o da Resolu????o 5, de 28 de agosto de 1996

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A Resolu????o n?? 6, de 21 de junho de 2012 estabelece os crit??rios e procedimentos espec??ficos de avalia????o de desempenho individual e institucional e de atribui????o da Gratifica????o de Desempenho do Plano Geral de Cargos do Poder Executivo (GDPGPE).

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This work presents an analysis of the cultural and artistic field, positively compromised with social and political questions. The authors start with the categorization of the idea of culture and move to vindication art movements. These movements, which followed the first vanguards and worked from the compromise with “otherness”, are at the origin of the contemporary denomination of political art. In this context, the authors approach the origins of activist art, referring to issues of gender, multiculturalism, globalization, and poverty. The different forms of presenting content are also an object of analysis: from art tradition to the contamination of daily life, from local to global, from street contact to digital.