975 resultados para Uranus (Planet)


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The compelling quality of the Global Change simulation study (Altemeyer, 2003), in which high RWA (right-wing authoritarianism)/high SDO (social dominance orientation) individuals produced poor outcomes for the planet, rests on the inference that the link between high RWA/SDO scores and disaster in the simulation can be generalized to real environmental and social situations. However, we argue that studies of the Person × Situation interaction are biased to overestimate the role of the individual variability. When variables are operationalized, strongly normative items are excluded because they are skewed and kurtotic. This occurs both in the measurement of predictor constructs, such as RWA, and in the outcome constructs, such as prejudice and war. Analyses of normal linear statistics highlight personality variables such as RWA, which produce variance, and overlook the role of norms, which produce invariance. Where both normative and personality forces are operating, as in intergroup contexts, the linear analysis generates statistics for the sample that disproportionately reflect the behavior of the deviant, antinormative minority and direct attention away from the baseline, normative position. The implications of these findings for the link between high RWA and disaster are discussed.

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Two new implementations of a tethered satellite system to provide aeroassist during a planetary flyby are investigated. In each mission scenario the interaction of the Martian atmosphere with an aerodynamic lifting surface, which is tethered to an orbiter, is used to perturb the flight path of the system. The aerodynamic forces generated by interacting with the atmosphere augment the gravity assist provided by the planet. In the first aerogravity-assist maneuver the tethered satellite system has congruent post- and preflyby configurations. The second scenario, which is referred to as a dual-destination mission, involves the system mass being separated during the flyby. Both of these aerogravity-assist maneuvers are shown to facilitate significant, propellant-free velocity changes.

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Understanding how climate change will affect the planet is a key issue worldwide. Questions concerning the pace and impacts of climate change are thus central to many ecological and biogeochemical studies, and addressing the consequences of climate change is now high on the list of priorities for funding agencies. Here, we review the interactions between climate change and plankton communities, focusing on systematic changes in plankton community structure, abundance, distribution and phenology over recent decades. We examine the potential socioeconomic impacts of these plankton changes, such as the effects of bottom-up forcing on commercially exploited fish stocks (i.e. plankton as food for fish). We also consider the crucial roles that plankton might have in dictating the future pace of climate change via feedback mechanisms responding to elevated atmospheric CO2 levels. An important message emerges from this review: ongoing plankton monitoring programmes worldwide will act as sentinels to identify future changes in marine ecosystems.

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Understanding and explaining emergent constitutive laws in the multi-scale evolution from point defects, dislocations and two-dimensional defects to plate tectonic scales is an arduous challenge in condensed matter physics. The Earth appears to be the only planet known to have developed stable plate tectonics as a means to get rid of its heat. The emergence of plate tectonics out of mantle convection appears to rely intrinsically on the capacity to form extremely weak faults in the top 100 km of the planet. These faults have a memory of at least several hundred millions of years, yet they appear to rely on the effects of water on line defects. This important phenomenon was first discovered in laboratory and dubbed ``hydrolytic weakening''. At the large scale it explains cycles of co-located resurgence of plate generation and consumption (the Wilson cycle), but the exact physics underlying the process itself and the enormous spanning of scales still remains unclear. We present an attempt to use the multi-scale non-equilibrium thermodynamic energy evolution inside the deforming lithosphere to move phenomenological laws to laws derived from basic scaling quantities, develop self-consistent weakening laws at lithospheric scale and give a fully coupled deformation-weakening constitutive framework. At meso- to plate scale we encounter in a stepwise manner three basic domains governed by the diffusion/reaction time scales of grain growth, thermal diffusion and finally water mobility through point defects in the crystalline lattice. The latter process governs the planetary scale and controls the stability of its heat transfer mode.

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On a global scale basalts from mid-ocean ridges are strikingly more homogeneous than basalts from intraplate volcanism. The observed geochemical heterogeneity argues strongly for the existence of distinct reservoirs in the Earth's mantle. It is an unresolved problem of Geodynamics as to how these findings can be reconciled with large-scale convection. We review observational constraints, and investigate stirring properties of numerical models of mantle convection. Conditions in the early Earth may have supported layered convection with rapid stirring in the upper layers. Material that has been altered near the surface is transported downwards by small-scale convection. Thereby a layer of homogeneous depleted material develops above pristine mantle. As the mantle cools over Earth history, the effects leading to layering become reduced and models show the large-scale convection favoured for the Earth today. Laterally averaged, the upper mantle below the lithosphere is least affected by material that has experienced near-surface differentiation. The geochemical signature obtained during the previous episode of small-scale convection may be preserved there for the longest time. Additionally, stirring is less effective in the high viscosity layer of the central lower mantle [1, 2], supporting the survival of medium-scale heterogeneities there. These models are the first, using 3-d spherical geometry and mostly Earth-like parameters, to address the suggested change of convective style. Although the models are still far from reproducing our planet, we find that proposal might be helpful towards reconciling geochemical and geophysical constraints.

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Arguably, the world has become one large pervasive computing environment. Our planet is growing a digital skin of a wide array of sensors, hand-held computers, mobile phones, laptops, web services and publicly accessible web-cams. Often, these devices and services are deployed in groups, forming small communities of interacting devices. Service discovery protocols allow processes executing on each device to discover services offered by other devices within the community. These communities can be linked together to form a wide-area pervasive environment, allowing processes in one p u p tu interact with services in another. However, the costs of communication and the protocols by which this communication is mediated in the wide-area differ from those of intra-group, or local-area, communication. Communication is an expensive operation for small, battery powered devices, but it is less expensive for servem and workstations, which have a constant power supply and 81'e connected to high bandwidth networks. This paper introduces Superstring, a peer to-peer service discovery protocol optimised fur use in the wide-area. Its goals are to minimise computation and memory overhead in the face of large numbers of resources. It achieves this memory and computation scalability by distributing the storage cost of service descriptions and the computation cost of queries over multiple resolvers.

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Aliadas aos estudos sobre sustentabilidade, há inúmeras discussões e atitudes para combater consequências do uso irracional dos recursos naturais do planeta. Surge assim o entendimento do consumo, suas influências e alternativas. O indivíduo pode ter hábitos de consumo de forma consumista ou de forma consciente. O consumista é entendido como o oposto dos hábitos do consumidor consciente, sendo levado pelo impulso e pelo estímulo à compra, sem avaliar suas necessidades e impactos futuros. O consumo é de fato indispensável à humanidade. Entretanto, quando aplicado de forma exacerbada e incorreta, pode gerar sérias consequências sociais e/ou ambientais. O consumidor consciente tem a qualificação de avaliar dentre as possibilidades existentes, os impactos que podem ser ocasionados com a aquisição, de tal modo, a minimizar suas consequências e contribuir de alguma forma para uma sociedade mais sustentável. O principal objetivo desta pesquisa foi compreender a aderência dos pesquisados ao comportamento de consumo consciente, bem como avaliar o compartilhamento de informações sobre o tema por pessoas que estão inseridas em alguma rede social na internet, partindo do pressuposto que este é um dos principais meios de comunicação e compartilhamento de informações. Para a pesquisa, foi utilizada a metodologia de análise qualitativa de caráter exploratório e a técnica de entrevistas em profundidade baseada em roteiro semiestruturado. Por meio da análise do conteúdo, a compreensão dos resultados aponta que todos os entrevistados possuem um grau de conhecimento sobre o consumo consciente e a maioria tenta ter algum tipo de ação consciente. Mas, ao mesmo tempo, esses indivíduos podem sofrer influências neste processo principalmente de caráter pessoal, levando à alteração de ação. Com relação ao compartilhamento do tema nas redes sociais na internet, foi possível identificar que grande parte dos entrevistados já teve algum tipo de experiência da situação, mas ainda em pequena escala, com poucas ocorrências. Também acredita-se que o canal pode ser utilizado para a proliferação do tema, o que nos leva à conclusão de que é um canal viável ao compartilhamento. Porém, mediante a ruptura de hábitos, é utilizado para a ocorrência de um maior engajamento por parte dos usuários. A análise apresenta uma compreensão e perspectivas a partir do recorte estudado, abrindo horizonte para novos estudos e aprofundamento das reflexões apresentadas neste trabalho.

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Freshwater is extremely precious; but even more precious than freshwater is clean freshwater. From the time that 2/3 of our planet is covered in water, we have contaminated our globe with chemicals that have been used by industrial activities over the last century in a unprecedented way causing harm to humans and wildlife. We have to adopt a new scientific mindset in order to face this problem so to protect this important resource. The Water Framework Directive (European Parliament and the Council, 2000) is a milestone legislative document that transformed the way that water quality monitoring is undertaken across all Member States by introducing the Ecological and Chemical Status. A “good or higher” Ecological Status is expected to be achieved for all waterbodies in Europe by 2015. Yet, most of the European waterbodies, which are determined to be at risk, or of moderate to bad quality, further information will be required so that adequate remediation strategies can be implemented. To date, water quality evaluation is based on five biological components (phytoplankton, macrophytes and benthic algae, macroinvertebrates and fishes) and various hydromorphological and physicochemical elements. The evaluation of the chemical status is principally based on 33 priority substances and on 12 xenobiotics, considered as dangerous for the environment. This approach takes into account only a part of the numerous xenobiotics that can be present in surface waters and could not evidence all the possible causes of ecotoxicological stress that can act in a water section. The mixtures of toxic chemicals may constitute an ecological risk not predictable on the basis of the single component concentration. To improve water quality, sources of contamination and causes of ecological alterations need to be identified. On the other hand, the analysis of the community structure, which is the result of multiple processes, including hydrological constrains and physico-chemical stress, give back only a “photograph” of the actual status of a site without revealing causes and sources of the perturbation. A multidisciplinary approach, able to integrate the information obtained by different methods, such as community structure analysis and eco-genotoxicological studies, could help overcome some of the difficulties in properly identifying the different causes of stress in risk assessment. In synthesis, the river ecological status is the result of a combination of multiple pressures that, for management purposes and quality improvement, have to be disentangled from each other. To reduce actual uncertainty in risk assessment, methods that establish quantitative links between levels of contamination and community alterations are needed. The analysis of macrobenthic invertebrate community structure has been widely used to identify sites subjected to perturbation. Trait-based descriptors of community structure constitute a useful method in ecological risk assessment. The diagnostic capacity of freshwater biomonitoring could be improved by chronic sublethal toxicity testing of water and sediment samples. Requiring an exposure time that covers most of the species’ life cycle, chronic toxicity tests are able to reveal negative effects on life-history traits at contaminant concentrations well below the acute toxicity level. Furthermore, the responses of high-level endpoints (growth, fecundity, mortality) can be integrated in order to evaluate the impact on population’s dynamics, a highly relevant endpoint from the ecological point of view. To gain more accurate information about potential causes and consequences of environmental contamination, the evaluation of adverse effects at physiological, biochemical and genetic level is also needed. The use of different biomarkers and toxicity tests can give information about the sub-lethal and toxic load of environmental compartments. Biomarkers give essential information about the exposure to toxicants, such as endocrine disruptor compounds and genotoxic substances whose negative effects cannot be evidenced by using only high-level toxicological endpoints. The increasing presence of genotoxic pollutants in the environment has caused concern regarding the potential harmful effects of xenobiotics on human health, and interest on the development of new and more sensitive methods for the assessment of mutagenic and cancerogenic risk. Within the WFD, biomarkers and bioassays are regarded as important tools to gain lines of evidence for cause-effect relationship in ecological quality assessment. Despite the scientific community clearly addresses the advantages and necessity of an ecotoxicological approach within the ecological quality assessment, a recent review reports that, more than one decade after the publication of the WFD, only few studies have attempted to integrate ecological water status assessment and biological methods (namely biomarkers or bioassays). None of the fifteen reviewed studies included both biomarkers and bioassays. The integrated approach developed in this PhD Thesis comprises a set of laboratory bioassays (Daphnia magna acute and chronic toxicity tests, Comet Assay and FPG-Comet) newly-developed, modified tacking a cue from standardized existing protocols or applied for freshwater quality testing (ecotoxicological, genotoxicological and toxicogenomic assays), coupled with field investigations on macrobenthic community structures (SPEAR and EBI indexes). Together with the development of new bioassays with Daphnia magna, the feasibility of eco-genotoxicological testing of freshwater and sediment quality with Heterocypris incongruens was evaluated (Comet Assay and a protocol for chronic toxicity). However, the Comet Assay, although standardized, was not applied to freshwater samples due to the lack of sensitivity of this species observed after 24h of exposure to relatively high (and not environmentally relevant) concentrations of reference genotoxicants. Furthermore, this species demonstrated to be unsuitable also for chronic toxicity testing due to the difficult evaluation of fecundity as sub-lethal endpoint of exposure and complications due to its biology and behaviour. The study was applied to a pilot hydrographic sub-Basin, by selecting section subjected to different levels of anthropogenic pressure: this allowed us to establish the reference conditions, to select the most significant endpoints and to evaluate the coherence of the responses of the different lines of evidence (alteration of community structure, eco-genotoxicological responses, alteration of gene expression profiles) and, finally, the diagnostic capacity of the monitoring strategy. Significant correlations were found between the genotoxicological parameter Tail Intensity % (TI%) and macrobenthic community descriptors SPEAR (p<0.001) and EBI (p<0.05), between the genotoxicological parameter describing DNA oxidative stress (ΔTI%) and mean levels of nitrates (p<0.01) and between reproductive impairment (Failed Development % from D. magna chronic bioassays) and TI% (p<0.001) as well as EBI (p<0.001). While correlation among parameters demonstrates a general coherence in the response to increasing impacts, the concomitant ability of each single endpoint to be responsive to specific sources of stress is at the basis of the diagnostic capacity of the integrated approach as demonstrated by stations presenting a mismatch among the different lines of evidence. The chosen set of bioassays, as well as the selected endpoints, are not providing redundant indications on the water quality status but, on the contrary, are contributing with complementary pieces of information about the several stressors that insist simultaneously on a waterbody section providing this monitoring strategy with a solid diagnostic capacity. Our approach should provide opportunities for the integration of biological effects into monitoring programmes for surface water, especially in investigative monitoring. Moreover, it should provide a more realistic assessment of impact and exposure of aquatic organisms to contaminants. Finally this approach should provide an evaluation of drivers of change in biodiversity and its causalities on ecosystem function/services provision, that is the direct and indirect contributions to human well-being.

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Esta tese objetiva comprovar que, na sociedade de consumo, indivíduos consumistas transcendem sua relação funcional com as mercadorias, buscando nas marcas de prestígio uma dimensão espiritual, que substitui ou complementa as experiências religiosas tradicionais, e que se revela fetichizada. O consumismo é superlativo de compras, posses e uso, uma dependência de bens não essenciais (supérfluos) para atender aos desejos sem fim. É impossível satisfazer a desejos sem fim: daí a expressão meta transcendental do consumo, posicionada além do alcance e da capacidade de atingi-la. A dimensão transcendente do consumo, por meio do simbolismo das mercadorias potencializado pelas marcas de prestígio, propicia encantamento e sentido ao indivíduo, e se presta a preencher o espaço outrora ocupado pela família, Igreja e comunidade. O sujeito busca, na mercadoria fetichizada pela marca, satisfazer seu desejo mimético, e/ou compensar valores frágeis ou ausentes, o que é reforçado pela propaganda. O sentido último da vida dos indivíduos materialistas produz efeitos imediatos que são positivos para eles e para a economia, mas potencialmente negativos mais à frente para o planeta, para sociedade e para os indivíduos.

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Esta pesquisa propõe-se a analisar a práxis pastoral litúrgica ecológica na Igreja Metodista. A práxis é a atividade reflexiva e material do ser humano, é ação transformadora, para uma pastoral ecoliturgica na dimensão pública da fé. A pesquisa consiste em estudar a interrelação que deve existir entre Liturgia e Ecologia, a partir dos conceitos bilbicos e a forma como a práxis pode influir e se articular para o desenvolvimento de uma ecoliturgia na realidade atual, tendo como espaço de referência a Igreja Metodista. A pesquisa se desenvolve em três etapas: Na primeira analisa conceitos teóricos de liturgia, sua história, mudanças e experiências do ser humano nas celebrações ligadas aos elementos da natureza; Na segunda, os conceitos de ecologia, sua crise e suas inter-relações com o Todo. Na terceira, os apontamentos para uma práxis pastoral ecolitúrgica na Igreja Metodista, como referencial para criar ações que conscientizem, mobilizem, para o reencantamento da espiritualidade, do sentido da vida e da ecologia, a fim de produzir esperança, diante das causas sociais que dizem respeito à vida integral do ser humano. O resultado será um conjunto de referenciais históricos e teóricos capazes de desconstruir, construir e reconstruir, a fim de sustentar uma práxis pastoral ecolitúrgica. Com o objetivo de realizar uma nova hermenêutica do tema num novo paradigma para as questões da realidade, tendo em vista a dimensão publica da fé na relação de Deus na criação e a práxis da igreja na sociedade. Na necessidade que o ser humano tem de se reencantar, reconhecer, saber cuidar, reconstruir tudo que nos garante a possibilidade da vida e a sustentabilidade no planeta.

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The world's communications infrastructure is poised to undergo a revolution. Networks that send light pulses through optical fibres and optical amplifiers will change the way in which we communicate across the planet.

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Using various extracts from the reflective commentaries of MSc students, this article explores how transdisciplinarity and reflective practice operate in the programme. It shows how learners managed the uncertainties of sustainable development through regular critical and evaluative reflections. Students were able to apprehend the several worlds making up the sustainable development project and their own personal learning journey through the various competing, complementary and occasionally contradictory perspectives, modes of learning, sources of knowledge and information. One conceptual device facilitating this process was offering an understanding of sustainable development as constituting a ‘dialogue of values’, an approach that effectively invites students to square the metaphorical circle - i.e. broadly reconciling (ecological) sustainability with (economic) development.

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Purpose – The purpose of this paper is to illustrate Michael Thomas's concept of civic professionalism and social trusteeship as a future alternative to the current marketing profession's code of conduct and to put this in the context of climate change and ecological sustainability as a model for firms everywhere. Design/methodology/approach – Review of the marketing profession's responsibility towards society, communities and the ecology of the planet in the twenty-first century in the light of climate change. Findings – The hypothesis for the paper emerges as: whether it is possible for Chinese firms to embrace the needs of twenty-first century global ecological sustainability in meeting their own economic requirements for development and financial prosperity. Research limitations/implications – Limited secondary research and primary research that is also limited in terms of scope. Practical implications – As we move into an era of Chinese economic supremacy, we marketers must face up to the responsibility we have towards balancing the progression of global economic development (and selling goods and services in global market systems) with our responsibility towards our cultural systems and the global ecological system (the global ecosystem), the home of all our economic wealth. Social implications – To extrapolate lessons and opportunities for firms from developing economies as they move towards global domination of world economic markets and, suggest strategies for sustainability that they can, and should, adopt. Originality/value – The paper presents a theoretical framework for a global strategy for sustainability, and provides a vision of marketing responsibility that embraces civic professionalism, social trusteeship and a strategy for sustainability.

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Purpose – The purpose of this paper is to present the concept of global “strategic sustainability”, represented by a conceptual framework, the “spheres of strategic sustainability”. The paper examines routes, solutions and a vision for corporate strategic sustainability in the macro context of the global physical environment and the planet. This builds on previous research identifying key drivers and strategies for corporate sustainability. Design/methodology/approach – The paper is conceptual in nature and underpinned by Gaia theory, ecosystems theory and the laws of thermodynamics. These three offer specific foci for sustainability research including holism, integration and synthesis: without which, sustainability research would be difficult to achieve. Findings – The paper identifies two major domains – “corporate” and “consumer” strategic sustainability. It examines the corporate domain in which routes are identified through responses to existing globalisation, corporate strategy and corporate culture. Research limitations/implications – The paper provides insight and preliminary conceptual development towards a full theoretical model of corporate and consumer strategic sustainability. The framework will guide future conceptual and empirical investigations and broaden and deepen our understanding of how firm's can construct strategic business models that incorporate sustainability. Originality/value – The paper offers a conceptual framework that develops the concept of “corporate strategic sustainability” and provides positive, practical solutions to incorporating sustainability into business models. It also challenges the current dominant socio-economic paradigm and sets the scene for a more positive eco-paradigm that serves the present and future needs of the planet, environment, businesses and human society.

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In this article we envision factors and trends that shape the next generation of environmental monitoring systems. One key factor in this respect is the combined effect of end-user needs and the general development of IT services and their availability. Currently, an environmental (monitoring) system is assumed to be reactive. It delivers measurement data and computational results only if the user explicitly asks for it either by query or subscription. There is a temptation to automate this by simply pushing data to end-users. This, however, leads easily to an "advertisement strategy", where data is pushed to end-users regardless of users' needs. Under this strategy, the mere amount of received data obfuscates the individual messages; any "automatic" service, regardless of its fitness, overruns a system that requires the user's initiative. The foreseeable problem is that, unless there is no overall management, each new environmental service is going to compete for end-users' attention and, thus, inadvertently hinder the use of existing services. As the main contribution we investigate the nature of proactive environmental systems, and how they should be designed to avoid the aforementioned problem. We also discuss how semantics, participatory sensing, uncertainty management, and situational awareness link to proactive environmental systems. We illustrate our proposals with some real-life examples.