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1.
Disposal of urban, agricultural and industrial organic residues impliesan increasing problem because of all the economic and environmentalrepercussions involved. One of the most adequate ways of managing this problemis the agricultural use of these wastes as organic amendments. Three organicresidues (AC, olive mill waste water sludge compost; MWC, municipal solid wastecompost; and PS, paper mill sludge) were used in a 3-year field experimentinvolving orange production. The effect of their application on crop productionand on soil quality was investigated. Soil samples (0–20 cm depth)collected 11 months after the last soil amendment were analysed for: pH and EC,Kjeldahl-N, available-P, available-K, total organic carbon, humic substances,dehydrogenase, phosphatase, -glucosidase, urease andbenzoyl-argininamidehydrolysing protease (BAA-protease) activities. Generally, the application of the MWC and PSincreased orange yield when compared to control. Moreover, total organic carbonand humic substances significantly increased in soils treated with all theorganic amendments. Organic fertilisation increased the Kjeldahl-N andavailable-P contents of the soil. The application of the organic residues also causedsignificant increases in dehydrogenase, -glucosidase, urease andBAA-protease activities of the soil. Significant positive correlations (p <0.01) between these enzymatic activities and total organic carbon were foundforall treatments. Significant positive correlation between dehydrogenase, urease,-glucosidase, and BAA-protease and orange yield was also found. However,a clear inhibition of phosphatase activity was observed in soils treated withPS. The results indicate that the repeated application to the soil of moderateamounts of organic amendments has positive effects on the chemical andbiochemical properties of the soil, as well as on the orange yield.  相似文献   
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With nearly three million tourists per year, the Costa Brava (Spain) is one of the most frequently visited tourist areas on the Mediterranean coast. The aim of this article is to understand its hydrosocial cycle and to identify why water consumption per capita is decreasing in the region. Overall, this decrease is not related to a single factor. Instead, many factors, including the incorporation of technological and institutional innovations in water management, increasing levels of social awareness related to saving water, the introduction of alternative water resources, and increasing water prices, must be considered together.  相似文献   
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This paper presents a performance study for two well known quantized based watermarking schemes Scalar Costa Scheme (SCS), and Trellis Coded Quantization scheme (TCQ) in an independent domain. For our study, the independent domain is obtained by the combination of the cited schemes with Independent Component Analysis (ICA). The Independent Component Analysis is used while inserting and extracting the message. Thus a performance compromise improvement of the original SCS and TCQ schemes in terms of robustness, capacity, and security is shown. Then the obtained schemes performances are compared to the Spread Transform (ST) based scheme well known for its proven good robustness properties. Our results show that, using watermarking with side information in independent domain permits to improve the global SCS and TCQ schemes performances. For example, in the case of SCS, by studying the Bit Error Rate (BER) in function of the watermark to noise ratio (WNR), the robustness has been improved by 20 dB (1 decade) when WNR is equal to 0 dB. Moreover, the capacity study shows for the same WNR=0 dB, the amount of information to be transmitted without error for a given noise level of the proposed SCS combined with ICA scheme (SCS-ICA) is much higher than that of the existing schemes. Finally, the study of the probability density functions (PDF) of the original and marked signals has shown that the Cachin-security level of the TCQ in an independent domain scheme (TCQ-ICA) is the best one compared to the other known schemes.  相似文献   
4.
Chair to the Australian government's Review of the National Innovation System in 2008, Terry Cutler is an industry consultant and strategy advisor with a background in the information and communications technology sector. Here, he opens up the question of architectural innovation to the wider context of the economy and social need. If architects are to innovatively address pressing social and environmental issues, such as climate change, obesity, population ageing and resource depletion, how does the architect's role need to be reformulated?  相似文献   
5.
Resilience—the ability of systems to cope with external shocks and trends—is a topic of increasing interest to research and practice. That growing interest is reflected within information systems (IS), but a structured review of IS literature shows a number of knowledge gaps around the conceptual and empirical application of resilience. This paper investigates what the subdiscipline of information and communication technologies for development (ICT4D) can contribute; finding that it offers the IS discipline fresh insights that can be built into a new framework of resilience, and an arena within which this new framework can appropriately be field tested. Application of the resilience framework was undertaken through interviews and a survey in an urban community in Costa Rica; benchmarking both community resilience and “e‐resilience” (understood here as the contribution of ICTs to community resilience), and developing from these a set of action priorities. The paper reflects on what can be learned generally from this conceptualisation and operationalisation of resilience. It also reflects on what ICTs contribute to resilience in developing countries and on what this ICT4D‐based research specifically contributes to the identified IS knowledge gaps. This includes identification of a future research agenda on information systems and resilience.  相似文献   
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Are bricks passé? Or is the contemporary world just failing to realise the innate possibilities of this ancient material? Eladio Dieste once ardently stated that brick is ‘a material with unlimited possibilities, almost completely ignored by modern technology.’1 Dieste's careful inclusion of the word ‘almost’ here seems to suggest that he suspected some exceptions to the rule – that there may have been some previously untold modern technological dabblings with brick. With this in mind, Defne Sunguroglu acknowledges the innovative uses of brick in the past, and introduces her current research project: Complex Brick Assemblies. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
9.
Plants defend themselves against herbivores and pathogens with a suite of morphological, phenological, biochemical, and biotic defenses, each of which is presumably costly. The best studied are allocation costs that involve trade-offs in investment of resources to defense versus other plant functions. Decreases in growth or reproductive effort are the costs most often associated with antiherbivore defenses, but trade-offs among different defenses may also occur within a single plant species. We examined trade-offs among defenses in closely related tropical rain forest shrubs (Piper cenocladum, P. imperiale, and P. melanocladum) that possess different combinations of three types of defense: ant mutualists, secondary compounds, and leaf toughness. We also examined the effectiveness of different defenses and suites of defenses against the most abundant generalist and specialist Piper herbivores. For all species examined, leaf toughness was the most effective defense, with the toughest species, P. melanocladum, receiving the lowest incidence of total herbivory, and the least tough species, P. imperiale, receiving the highest incidence. Although variation in toughness within each species was substantial, there were no intraspecific relationships between toughness and herbivory. In other Piper studies, chemical and biotic defenses had strong intraspecific negative correlations with herbivory. A wide variety of defensive mechanisms was quantified in the three Piper species studied, ranging from low concentrations of chemical defenses in P. imperiale to a complex suite of defenses in P. cenocladum that includes ant mutualists, secondary metabolites, and moderate toughness. Ecological costs were evident for the array of defensive mechanisms within these Piper species, and the differences in defensive strategies among species may represent evolutionary trade-offs between costly defenses.  相似文献   
10.
How can an ancient architectural heritage become a rich resource for inspiration rather than a burden or a limitation? Moving away from a conventional formal analysis of historic architecture, which identifies particular periods with specific styles or characteristics, Farshad Farahi suggests an approach that unites the contemporary philosophically and spiritually with its past - by seeking out an imaginary dimension or ‘World of Similitude’.  相似文献   
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