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91.
As pressures on coastal zones mount, there is a growing need for frameworks that can be used to conceptualize complex sustainability challenges and help organize research that increases understand about interacting ecological and societal processes, predicts change, and supports the management, persistence, and resilience of coastal systems. The Driver–Pressure–State–Impact–Response (DPSIR) framework is one such approach that has been adopted in some coastal zones around the world. Although the application of the DPSIR framework has considerable potential to bridge the gap between scientific disciplines and link science to coastal policy and management, current applications of DPSIR in coastal environments have been limited and new innovations in the application of the DPSIR model are needed. We conducted a structured review of literature on the DPSIR framework as applied to the function, process and components of complex coastal systems. Our specific focus was on how the DPSIR framework has been used as a tool to organize sophisticated empirical scientific research, support transdisciplinary knowledge at a level appropriate for building understanding about coastal systems, and how adopting a DPSIR approach can help stakeholders to articulate and structure challenges in coastal systems and use the framework to support policy and management outcomes. The review revealed that DPSIR models of coastal systems have been largely used to support and develop conceptual understanding of coastal social–ecological systems and to identify drivers and pressures in the coastal realm. A limited number of studies have used DPSIR as a starting point for semi-quantitative or quantitative analyses, although our review highlights the continued need for, and potential of, transformative quantitative analyses and transdisciplinary applications of the DPSIR framework. The DPSIR models we reviewed were predominantly single sector, encompassing ecological or biophysical factors or focusing primarily on socio-cultural dimensions rather than full integration of both types of information. Only in eight of 24 shortlisted articles did researchers actively engage decision-makers or citizens in their research: given the potential opportunity for using DPSIR as a tool to successfully engage policy-makers and stakeholders, it appears that the DPSIR framework has been under-utilized in this regard.  相似文献   
92.
The diagnosis of Silver–Russell syndrome is based on the characteristic growth restriction and the presence of typical dysmorphic features. We present the prenatal and postnatal findings of a case that was treated at our perinatal center. The suspected diagnosis Silver–Russell syndrome was confirmed after delivery by our medical genetic and neonatology services. The authors want to point out that SRS should be considered in the differential diagnosis of early asymmetric intrauterine growth restriction. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
93.
We consider the resource-extraction policy of a government that is lobbied by an environmental organization and an extraction firm from foreign countries. To analyze this situation, we propose a sequential Nash bargaining solution: The government bargains with both lobbies simultaneously. Should this trilateral negotiation fail, it chooses one lobby for a bilateral negotiation. The disagreement point then is to bargain with the other lobby. Finally, should this second bilateral negotiation break down, the government chooses the welfare-maximizing policy.As long as cumulative extraction is low, such that stock-dependent extraction costs are also low and extraction profits are high, the environmental organization has a weak bargaining position, but it takes influence to reduce extraction. Once that cumulative extraction has increased so much that extraction profits are below a threshold, the bargaining positions change, and the environmental organization gets compensated by the extraction firm for not letting the trilateral negotiation fail.  相似文献   
94.
In this research a gas–liquid fluidized bed reactor was developed for removing chlorine (Cl) from polyvinyl chloride (PVC) to favor its pyrolysis treatment. In order to efficiently remove Cl within a limited time before extensive generation of hydrocarbon products, the gas–liquid fluidized bed reactor was running at 280–320 °C, where hot N2 was used as fluidizing gas to fluidize the molten polymer, letting the molten polymer contact well with N2 to release Cl in form of HCl. Experimental results showed that dechlorination efficiency is mainly temperature dependent and 300 °C is a proper reaction temperature for efficient dechlorination within a limited time duration and for prevention of extensive pyrolysis; under this temperature 99.5% of Cl removal efficiency can be obtained within reaction time around 1 min after melting is completed as the flow rate of N2 gas was set around 0.47–0.85 Nm3 kg?1 for the molten PVC. Larger N2 flow rate and additives in PVC would enhance HCl release but did not change the final dechlorination efficiency; and excessive N2 flow rate should be avoided for prevention of polymer entrainment. HCl is emitted from PVC granules or scraps at the mean time they started to melt and the melting stage should be taken into consideration when design the gas–liquid fluidized bed reactor for dechlorination.  相似文献   
95.
As far as the optimal design, operation, and field application of the Aerobic–Anaerobic Landfill Method (AALM) are concerned, it is very important to understand how aeration modes (different combinations of aeration depth and air injection rate) affect the biodegradation of organic carbon and the transformation of nitrogen in landfill solid waste. Pilot-scale lysimeter experiments were carried out under different aeration modes to obtain detailed information regarding the influence of aeration modes on leachate characteristics. Results from these lysimeter experiments revealed that aeration at the bottom layer was the most effective for decomposition of organic carbon when compared with aeration at the surface or middle layers. Moreover, the air injection rate led to different nitrogen transformation patterns, unlike the lesser influence it has on organic carbon decomposition. Effective simultaneous nitrification and denitrification were observed for the aeration mode with a higher air injection rate (=1.0 L/min). On the other hand, the phenomenon of sequenced nitrification and denitrification could be observed when a low air injection rate (=0.5 L/min.) was employed. Finally, it is concluded that, for AALM, air injection with a higher air injection rate at the deepest layer near the leachate collection pipe tends to accelerate the stabilization of landfill waste as defined in terms of the enhancement of denitrification as well as organic carbon decomposition.  相似文献   
96.
The aim of this study was to investigate the feasibility of using visible near-infrared (VisNIR) diffuse reflectance spectroscopy (DRS) as an easy, inexpensive, and rapid method to predict compost enzymatic activity, which traditionally measured by fluorescein diacetate hydrolysis (FDA-HR) assay. Compost samples representative of five different compost facilities were scanned by DRS, and the raw reflectance spectra were preprocessed using seven spectral transformations for predicting compost FDA-HR with six multivariate algorithms. Although principal component analysis for all spectral pretreatments satisfactorily identified the clusters by compost types, it could not separate different FDA contents. Furthermore, the artificial neural network multilayer perceptron (residual prediction deviation = 3.2, validation r2 = 0.91 and RMSE = 13.38 μg g?1 h?1) outperformed other multivariate models to capture the highly non-linear relationships between compost enzymatic activity and VisNIR reflectance spectra after Savitzky–Golay first derivative pretreatment. This work demonstrates the efficiency of VisNIR DRS for predicting compost enzymatic as well as microbial activity.  相似文献   
97.
Natura 2000, the nature network based on the European Bird and Habitat Directives, is explicitly grounded on ecological science. To acquire a permit under the Dutch Nature Conservation Act, an appropriate assessment of significant effects must be conducted based on the best available scientific knowledge. In this way the scientific and policy world are directly linked. This article focuses on ‘significant effect’ as a boundary object to analyse how science–policy interactions shape the meaning and assessment of significant effect and how these interpretations influence the decision-making process. To this end, two conflicts over significant effect are investigated: the conflict over the 2006-spring permit for the mussel seed fishery, and the 2011 permit for the planned World Championship powerboat races. In both cases nature organisations started a court process against the government-granted permits in protest to the “no significant effect” claim, stating that there was insufficient certainty for this conclusion. These conflicts are approached as controversies between discourse coalitions with different interpretations of the ecological knowledge. We show how significant effect became a focal point in the controversies, limiting the debate to ecological arguments and science-based expertise, but also creating options for parties to advance their protest by articulating uncertainties. Only uncertainty of incomplete knowledge was explicitly addressed, excluding ambiguity of values and unpredictability of the actual ecosystem. We suggest that acknowledging the value aspect in disputes on significant effect would leave more space for effective solutions of the problems under debate.  相似文献   
98.
Linking landscapes to socio-economic benefits necessarily requires considering the usability of landscape structure. To do so, however, depends on the interaction between users and producers of landscape-related services. We illustrate this interaction with a Bayesian Belief Network (BBN) in a case study analysing the connection between residents' perceptions of landscape structure and agritourism restaurants in the eastern lowlands of Ferrara (Italy). We use estimates of prior and conditional probabilities from a mix of different data: land use, survey data, regional statistics, and expert judgements to show the likely effects of the landscape structure on the local economy by using intermediate forms of services (i.e. second-order services). The second-order service is highly influenced by the agritourism density and by the frequency with which customers dine at agritourism restaurants and less by landscape attractiveness, confirming the importance of the supply and demand of second-order services in the provision of landscape-related services.  相似文献   
99.
Nickel recovered in the recycling process of Ni–Cd batteries was used as a main component of bath for electrodeposition of nickel onto carbon fabric in order to obtain C/Ni composite. A part of the obtained composite was additionally coated with a thin layer of palladium (C/Ni/Pd composite). All the materials were investigated to assess the possibility of their use in the processes of electrochemical storage (sorption/desorption) of hydrogen and electrochemical oxidation of methanol. The obtained results showed the composites to be active electrode materials in these processes. The electrodes exhibited high activity and cyclability, especially in the process of methanol oxidation due to electrocatalytic activity of both nickel deposited onto carbon fabric and the outer layer of porous palladium coating nickel substrate.  相似文献   
100.
The purpose of this research was to evaluate the performance of combined biological/advanced oxidation process (AOP) system for treatment of wastewater containing high concentration (500 mg/L) of azo dye Acid Red 18 (AR18). Two alternating anaerobic–aerobic sequencing batch reactors (SBR1 and SBR2 without and with external feeding at the beginning of aeration cycle, respectively) were operated. The effluent of the SBRs was then post treated through enhanced Fenton process (using zero-valent iron combined with ultrasonic irradiation). More than 90% and 97% of COD was removed in the combined SBR/AOP system without external carbon source (CTS1) and with external feeding (CTS2), respectively. The analysis of dye and its metabolites using UV–vis and HPLC analysis also proved that 99% of the original dye was decolorized and more than 89% of its metabolites were degraded through CST2 which is significantly higher than the reported values in the literature. Besides, more than 87% of phosphorus removal efficiency was obtained in CST2 compared to only 54.5% removal efficiency in CST1. Regarding the findings of this study, the proposed combined treatment system (CTS2) can be suggested as an effective technique for treatment of high azo dye AR18 concentration wastewater.  相似文献   
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