886 resultados para Location-based services


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After the collective failure to achieve the Convention on Biological Diversity's (CBD's) 2010 target to substantially reduce biodiversity losses, the CBD adopted a plan composed of five strategic goals and 20 “SMART” (Specific, Measurable, Ambitious, Realistic, and Time-bound) targets, to be achieved by 2020. Here, an interdisciplinary group of scientists from DIVERSITAS – an international program that focuses on biodiversity science – evaluates these targets and considers the implications of an ecosystem-services-based approach for their implementation. We describe the functional differences between the targets corresponding to distinct strategic goals and identify the interdependency between targets. We then discuss the implications for supporting research and target indicators, and make several specific suggestions for target implementation.

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Inorganic nitrogen depletion restricts productivity in much of the low-latitude oceans, generating a selective advantage for diazotrophic organisms capable of fixing atmospheric dinitrogen (N2). However, the abundance and activity of diazotrophs can in turn be controlled by the availability of other potentially limiting nutrients, including phosphorus (P) and iron (Fe). Here we present high-resolution data (∼0.3°) for dissolved iron, aluminum, and inorganic phosphorus that confirm the existence of a sharp north–south biogeochemical boundary in the surface nutrient concentrations of the (sub)tropical Atlantic Ocean. Combining satellite-based precipitation data with results from a previous study, we here demonstrate that wet deposition in the region of the intertropical convergence zone acts as the major dissolved iron source to surface waters. Moreover, corresponding observations of N2 fixation and the distribution of diazotrophic Trichodesmium spp. indicate that movement in the region of elevated dissolved iron as a result of the seasonal migration of the intertropical convergence zone drives a shift in the latitudinal distribution of diazotrophy and corresponding dissolved inorganic phosphorus depletion. These conclusions are consistent with the results of an idealized numerical model of the system. The boundary between the distinct biogeochemical systems of the (sub)tropical Atlantic thus appears to be defined by the diazotrophic response to spatial–temporal variability in external Fe inputs. Consequently, in addition to demonstrating a unique seasonal cycle forced by atmospheric nutrient inputs, we suggest that the underlying biogeochemical mechanisms would likely characterize the response of oligotrophic systems to altered environmental forcing over longer timescales.

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This paper scrutinises the use of ecosystem service valuation for marine planning. Lessons are drawn from the development and use of environmental valuation and cost-benefit analysis for policy-making in the US and the UK. Current approaches to marine planning in both countries are presented and the role that ecosystem service valuation could play in this context is outlined. This includes highlighting the steps in the marine planning process where valuation can inform marine planning and policy-making as well as a discussion of methodological challenges to ecosystem service valuation techniques in the context of marine planning. Recommendations to overcome existing barriers are offered based on the synergies and the thinking in the two countries regarding the application of ecosystem service valuation to marine planning.

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Harmful algal blooms (HABs), those proliferations of algae that can cause fish kills, contaminate seafood with toxins, form unsightly scums, or detrimentally alter ecosystem function have been increasing in frequency, magnitude, and duration worldwide. Here, using a global modeling approach, we show, for three regions of the globe, the potential effects of nutrient loading and climate change for two HAB genera, pelagic Prorocentrum and Karenia, each with differing physiological characteristics for growth. The projections (end of century, 2090-2100) are based on climate change resulting from the A1B scenario of the Intergovernmental Panel on Climate Change Institut Pierre Simon Laplace Climate Model (IPCC, IPSL-CM4), applied in a coupled oceanographic-biogeochemical model, combined with a suite of assumed physiological 'rules' for genera-specific bloom development. Based on these models, an expansion in area and/or number of months annually conducive to development of these HABs along the NW European Shelf-Baltic Sea system and NE Asia was projected for both HAB genera, but no expansion (Prorocentrum spp.), or actual contraction in area and months conducive for blooms (Karenia spp.), was projected in the SE Asian domain. The implications of these projections, especially for Northern Europe, are shifts in vulnerability of coastal systems to HAB events, increased regional HAB impacts to aquaculture, increased risks to human health and ecosystems, and economic consequences of these events due to losses to fisheries and ecosystem services.

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This project was commissioned to generate an improved understanding of the sensitivities of seagrass habitats to pressures associated with human activities in the marine environment - to provide an evidence base to facilitate and support management advice for Marine Protected Areas; development of UK marine monitoring and assessment, and conservation advice to offshore marine industries. Seagrass bed habitats are identified as a Priority Marine Feature (PMF) under the Marine (Scotland) Act 2010, they are also included on the OSPAR list of threatened and declining species and habitats, and are a Habitat of Principle Importance (HPI) under the Natural Environment and Rural Communities (NERC) Act 2006, in England and Wales. The purpose of this project was to produce sensitivity assessments with supporting evidence for the HPI, OSPAR and PMF seagrass/Zostera bed habitat definitions, clearly documenting the evidence behind the assessments and any differences between assessments. Nineteen pressures, falling in five categories - biological, hydrological, physical damage, physical loss, and pollution and other chemical changes - were assessed in this report. Assessments were based on the three British seagrasses Zostera marina, Z. noltei and Ruppia maritima. Z. marina var. angustifolia was considered to be a subspecies of Z. marina but it was specified where studies had considered it as a species in its own rights. Where possible other components of the community were investigated but the basis of the assessment focused on seagrass species. To develop each sensitivity assessment, the resistance and resilience of the key elements were assessed against the pressure benchmark using the available evidence. The benchmarks were designed to provide a ‘standard’ level of pressure against which to assess sensitivity. Overall, seagrass beds were highly sensitive to a number of human activities: • penetration or disturbance of the substratum below the surface; • habitat structure changes – removal of substratum; • physical change to another sediment type; • physical loss of habitat; • siltation rate changes including and smothering; and • changes in suspended solids. High sensitivity was recorded for pressures which directly impacted the factors that limit seagrass growth and health such as light availability. Physical pressures that caused mechanical modification of the sediment, and hence damage to roots and leaves, also resulted in high sensitivity. Seagrass beds were assessed as ‘not sensitive’ to microbial pathogens or ‘removal of target species’. These assessments were based on the benchmarks used. Z. marina is known to be sensitive to Labyrinthula zosterae but this was not included in the benchmark used. Similarly, ‘removal of target species’ addresses only the biological effects of removal and not the physical effects of the process used. For example, seagrass beds are probably not sensitive to the removal of scallops found within the bed but are highly sensitive to the effects of dredging for scallops, as assessed under the pressure penetration or disturbance of the substratum below the surface‘. This is also an example of a synergistic effect Assessing the sensitivity of seagrass bed biotopes to pressures associated with marine activities between pressures. Where possible, synergistic effects were highlighted but synergistic and cumulative effects are outside the scope off this study. The report found that no distinct differences in sensitivity exist between the HPI, PMF and OSPAR definitions. Individual biotopes do however have different sensitivities to pressures. These differences were determined by the species affected, the position of the habitat on the shore and the sediment type. For instance evidence showed that beds growing in soft and muddy sand were more vulnerable to physical damage than beds on harder, more compact substratum. Temporal effects can also influence the sensitivity of seagrass beds. On a seasonal time frame, physical damage to roots and leaves occurring in the reproductive season (summer months) will have a greater impact than damage in winter. On a daily basis, the tidal regime could accentuate or attenuate the effects of pressures depending on high and low tide. A variety of factors must therefore be taken into account in order to assess the sensitivity of a particular seagrass habitat at any location. No clear difference in resilience was established across the three seagrass definitions assessed in this report. The resilience of seagrass beds and the ability to recover from human induced pressures is a combination of the environmental conditions of the site, growth rates of the seagrass, the frequency and the intensity of the disturbance. This highlights the importance of considering the species affected as well as the ecology of the seagrass bed, the environmental conditions and the types and nature of activities giving rise to the pressure and the effects of that pressure. For example, pressures that result in sediment modification (e.g. pitting or erosion), sediment change or removal, prolong recovery. Therefore, the resilience of each biotope and habitat definitions is discussed for each pressure. Using a clearly documented, evidence based approach to create sensitivity assessments allows the assessment and any subsequent decision making or management plans to be readily communicated, transparent and justifiable. The assessments can be replicated and updated where new evidence becomes available ensuring the longevity of the sensitivity assessment tool. The evidence review has reduced the uncertainty around assessments previously undertaken in the MB0102 project (Tillin et al 2010) by assigning a single sensitivity score to the pressures as opposed to a range. Finally, as seagrass habitats may also contribute to ecosystem function and the delivery of ecosystem services, understanding the sensitivity of these biotopes may also support assessment and management in regard to these. Whatever objective measures are applied to data to assess sensitivity, the final sensitivity assessment is indicative. The evidence, the benchmarks, the confidence in the assessments and the limitations of the process, require a sense-check by experienced marine ecologists before the outcome is used in management decisions.

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Ecosystems provide a range of goods and services that contribute toward human well-being. It is increasingly recognized that factors such as a growing and increasingly affluent world population, coupled with increased globalization of trade, are significantly influencing the delivery of ecosystem goods and services. This chapter argues that future energy policy must be designed based on a broad set of environmental and social considerations that examine the national and international implications of each energy technology. This approach ensures a more holistic overview of the costs and benefits associated with energy production, allowing society to make more informed choices about their futures, including how their energy is sourced, generated, and delivered.

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The EU Marine Strategy Framework Directive (MSFD) sets out a plan of action relating to marine environmental policy and in particular to achieving ‘good environmental status’ (GES) in European marine waters by 2020. Article 8.1 (c) of the Directive calls for ‘an economic and social analysis of the use of those waters and of the cost of degradation of the marine environment’. The MSFD is ‘informed’ by the Ecosystem Approach to management, with GES interpreted in terms of ecosystem functioning and services provision. Implementation of the Ecosystem Approach is expected to be by adaptive management policy and practice. The initial socio-economic assessment was made by maritime EU Member States between 2011 and 2012, with future updates to be made on a regular basis. For the majority of Member States, this assessment has led to an exercise combining an analysis of maritime activities both at national and coastal zone scales, and an analysis of the non-market value of marine waters. In this paper we examine the approaches taken in more detail, outline the main challenges facing the Member States in assessing the economic value of achieving GES as outlined in the Directive and make recommendations for the theoretically sound and practically useful completion of the required follow-up economic assessments specified in the MSFD.

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The EU Marine Strategy Framework Directive (MSFD) sets out a plan of action relating to marine environmental policy and in particular to achieving ‘good environmental status’ (GES) in European marine waters by 2020. Article 8.1 (c) of the Directive calls for ‘an economic and social analysis of the use of those waters and of the cost of degradation of the marine environment’. The MSFD is ‘informed’ by the Ecosystem Approach to management, with GES interpreted in terms of ecosystem functioning and services provision. Implementation of the Ecosystem Approach is expected to be by adaptive management policy and practice. The initial socio-economic assessment was made by maritime EU Member States between 2011 and 2012, with future updates to be made on a regular basis. For the majority of Member States, this assessment has led to an exercise combining an analysis of maritime activities both at national and coastal zone scales, and an analysis of the non-market value of marine waters. In this paper we examine the approaches taken in more detail, outline the main challenges facing the Member States in assessing the economic value of achieving GES as outlined in the Directive and make recommendations for the theoretically sound and practically useful completion of the required follow-up economic assessments specified in the MSFD.

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Previous research and service development guidelines have highlighted the importance of psychological issues in diabetes care, and both people with diabetes and diabetes professionals recognise the need for specialist psychological input. This article outlines the development of a service delivery model for psychological services in diabetes care, based on a patient needs assessment and the advice of diabetes professionals. This involved an assessment of the psychological needs of people with diabetes within an urban Health Trust in Northern Ireland, and the collation of the views of local diabetes professionals. Questionnaires to assess for depression, anxiety, binge eating behaviour and diabetes-specific worries were completed by 300 people with diabetes. The participants were accessed through both primary and secondary care diabetes teams. As expected, a high level of psychological distress relative to population norms was illustrated by the patient needs assessment. Particularly high levels of binge eating behaviour were reported, and levels of distress were higher for community-managed patients than for hospital-managed patients. The diabetes professionals unanimously agreed that there is a need for specialist psychological input and contributed to the service delivery model which is outlined in this article.

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As the expression of the genetic blueprint, proteins are at the heart of all biological systems. The ever increasing set of available protein structures has taught us that diversity is the hallmark of their architecture, a fundamental characteristic that enables them to perform the vast array of functionality upon which all of life depends. This diversity, however, is central to one of the most challenging problems in molecular biology: how does a folding polypeptide chain navigate its way through all of the myriad of possible conformations to find its own particular biologically active form? With few overarching structural principles to draw upon that can be applied to all protein architecture, the search for a solution to the protein folding problem has yet to produce an algorithm that can explain and duplicate this fundamental biological process. In this thesis, we take a two-pronged approach for investigating the protein folding process. Our initial statistical studies of the distributions of hydrophobic and hydrophilic residues within α-helices and β-sheets suggest (i) that hydrophobicity plays a critical role in helix and sheet formation; and (ii) that the nucleation of these motifs may result in largely unidirectional growth. Most tellingly, from an examination of the amino acids found in the smallest β-sheets, we do not find any evidence of a β-nucleating code in the primary protein sequence. Complementing these statistical analyses, we have analyzed the structural environments of several ever-widening aspects of protein topology. Our examination of the gaps between strands in the smallest β-sheets reveals a common organizational principle underlying β-formation involving strands separated by large sequential gaps: with very few exceptions, these large gaps fold into single, compact structural modules, bringing the β-strands that are otherwise far apart in the sequence close together in space. We conclude, therefore, that β-nucleation in the smallest sheets results from the co-location of two strands that are either local in sequence, or local in space following prior folding events. A second study of larger β-sheets both corroborates and extends these findings: virtually all large sequential gaps between pairs of β-strands organize themselves into an hierarchical arrangement, creating a bread-crumb model of go-and-come-back structural organization that ultimately juxtaposes two strands of a parental β-structure that are far apart in the sequence in close spatial proximity. In a final study, we have formalized this go-and-come-back notion into the concept of anti-parallel double-strandedness (DS), and measure this property across protein architecture in general. With over 90% of all residues in a large, non-redundant set of protein structures classified as DS, we conclude that DS is a unifying structural principle that underpins all globular proteins. We postulate, moreover, that this one simple principle, anti-parallel double-strandedness, unites protein structure, protein folding and protein evolution.

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The unique characteristics of credit unions reduces the information asymmetry that is prevalent in credit making decisions, enabling them to provide loans where other financial institutions cannot. This makes them a potential tool in the fight against financial exclusion. Yet, the UK credit union movement is not regarded as being successful, even though there is evidence of much financial exclusion. This study is cross sectional in form, and evaluates characteristics that may contribute to the success of the UK credit union movement at national and regional level, in 2000. The findings are used to consider the impact of recent regulatory changes on the movement. The key findings are that there is a significant relationship between the success of a credit union, its size and the deprivation of the ward from which it sources its members. More specifically, larger credit unions and those located in more affluent wards, are more successful. Affiliation to the Irish League of Credit Unions and having a common bond of occupation, are also found to be contributing factors to credit union success. These results are taken as providing support for the recent changes implemented by the Financial Services Authority (FSA), which is likely to result in the emergence of larger credit unions (through mergers), run by appropriately qualified persons, serving a more mixed-income membership base. It is, however, noted that the history of the UK movement is one of missed opportunities and only time will tell whether credit unions have the wherewithal to accept current opportunities.

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Objective: Patients with chronic kidney disease (CKD) benefit from specialist interventions to retard progression of renal failure and prevent cardiovascular events. Certain patient groups have poor access to specialist renal services when dialysis is required. This study used a population-based laboratory database to investigate access to and timeliness of referral to renal specialists relatively early in the course of the disease.

Methods: All tests for serum creatinine and haemoglobin (Hb) A1c in Northern Ireland in a two-year period (2001 and 2002) were retrieved for 345,441 adults. Of these, 16,856 patients had at least one serum creatinine level above 150 µmol/L in 2001 not deemed to be due to acute renal failure (crude prevalence 1.42%). This cohort was followed until the end of 2002 and the differences in the time to referral to a specialist were assessed using Cox's proportional hazards regression.

Results: Diabetic patients, older patients and those living in deprived areas were significantly more likely to have serum creatinine testing, compared with non-diabetic, younger and those living in more affluent areas. Delays in referral to renal specialists for patients with raised serum creatinine levels were significantly shorter among diabetic patients, women, younger individuals, those living in rural areas, those living close to renal centres and those living in deprived areas. Overall, only 19% of diabetic patients and 6% of non-diabetic patients who had CKD had seen a renal specialist within 12 months of their index creatinine test.

Conclusion: Contrary to other diseases, disadvantaged patients do not seem to be under-investigated for renal disease compared with their more affluent neighbours and are generally referred earlier for specialist assessment. However, the absolute rate of timely specialist assessment is low. Recent changes in referral criteria for CKD will result in more referrals and will have serious resource implications. Opportunities for health gain among patients with declining renal function are being missed, particularly among the old and those living furthest from specialist centres.

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In the IEEE 802.11 MAC layer protocol, there are different trade-off points between the number of nodes competing for the medium and the network capacity provided to them. There is also a trade-off between the wireless channel condition during the transmission period and the energy consumption of the nodes. Current approaches at modeling energy consumption in 802.11 based networks do not consider the influence of the channel condition on all types of frames (control and data) in the WLAN. Nor do they consider the effect on the different MAC and PHY schemes that can occur in 802.11 networks. In this paper, we investigate energy consumption corresponding to the number of competing nodes in IEEE 802.11's MAC and PHY layers in error-prone wireless channel conditions, and present a new energy consumption model. Analysis of the power consumed by each type of MAC and PHY over different bit error rates shows that the parameters in these layers play a critical role in determining the overall energy consumption of the ad-hoc network. The goal of this research is not only to compare the energy consumption using exact formulae in saturated IEEE 802.11-based DCF networks under varying numbers of competing nodes, but also, as the results show, to demonstrate that channel errors have a significant impact on the energy consumption.

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The future convergence of voice, video and data applications on the Internet requires that next generation technology provides bandwidth and delay guarantees. Current technology trends are moving towards scalable aggregate-based systems where applications are grouped together and guarantees are provided at the aggregate level only. This solution alone is not enough for interactive video applications with sub-second delay bounds. This paper introduces a novel packet marking scheme that controls the end-to-end delay of an individual flow as it traverses a network enabled to supply aggregate- granularity Quality of Service (QoS). IPv6 Hop-by-Hop extension header fields are used to track the packet delay encountered at each network node and autonomous decisions are made on the best queuing strategy to employ. The results of network simulations are presented and it is shown that when the proposed mechanism is employed the requested delay bound is met with a 20% reduction in resource reservation and no packet loss in the network.

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This paper presents a new packet scheduling scheme called agent-based WFQ to control and maintain QoS parameters in virtual private networks (VPNs) within the confines of adaptive networks. Future networks are expected to be open heterogeneous environments consisting of more than one network operator. In this adaptive environment, agents act on behalf of users or third-party operators to obtain the best service for their clients and maintain those services through the modification of the scheduling scheme in routers and switches spanning the VPN. In agent-based WFQ, an agent on the router monitors the accumulated queuing delay for each service. In order to control and to keep the end-to-end delay within the bounds, the weights for services are adjusted dynamically by agents on the routers spanning the VPN. If there is an increase or decrease in queuing delay of a service, an agent on a downstream router informs the upstream routers to adjust the weights of their queues. This keeps the end-to-end delay of services within the specified bounds and offers better QoS compared to VPNs using static WFQ. This paper also describes the algorithm for agent-based WFQ, and presents simulation results. (C) 2003 Elsevier Science Ltd. All rights reserved.