Showing papers by "Lancaster University published in 2008"
TL;DR: Overall, this review shows that soil microbes must be considered as important drivers of plant diversity and productivity in terrestrial ecosystems.
Abstract: Microbes are the unseen majority in soil and comprise a large portion of lifes genetic diversity. Despite their abundance, the impact of soil microbes on ecosystem processes is still poorly understood. Here we explore the various roles that soil microbes play in terrestrial ecosystems with special emphasis on their contribution to plant productivity and diversity. Soil microbes are important regulators of plant productivity, especially in nutrient poor ecosystems where plant symbionts are responsible for the acquisition of limiting nutrients. Mycorrhizal fungi and nitrogenfixing bacteria are responsible for c. 5‐20% (grassland and savannah) to 80% (temperate and boreal forests) of all nitrogen, and up to 75% of phosphorus, that is acquired by plants annually. Free-living microbes also strongly regulate plant productivity, through the mineralization of, and competition for, nutrients that sustain plant productivity. Soil microbes, including microbial pathogens, are also important regulators of plant community dynamics and plant diversity, determining plant abundance and, in some cases, facilitating invasion by exotic plants. Conservative estimates suggest that c. 20 000 plant species are completely dependent on microbial symbionts for growth and survival pointing to the importance of soil microbes as regulators of plant species richness on Earth. Overall, this review shows that soil microbes must be considered as important drivers of plant diversity and productivity in terrestrial ecosystems.
3,673 citations
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25 Aug 2008TL;DR: An overview of model-based geostatistics can be found in this paper, where a generalized linear model is proposed for estimating geometrical properties of geometrically constrained data.
Abstract: An overview of model-based geostatistics.- Gaussian models for geostatistical data.- Generalized linear models for geostatistical data.- Classical parameter estimation.- Spatial prediction.- Bayesian inference.- Geostatistical design.
2,397 citations
TL;DR: The authors discusses the extent to which methods normally associated with corpus linguistics can be effectively used by critical discourse analysts, based on the analysis of a 140-million-word corpus of British news articles about refugees, asylum seekers, immigrants and migrants.
Abstract: This article discusses the extent to which methods normally associated with corpus linguistics can be effectively used by critical discourse analysts. Our research is based on the analysis of a 140-million-word corpus of British news articles about refugees, asylum seekers, immigrants and migrants (collectively RASIM). We discuss how processes such as collocation and concordance analysis were able to identify common categories of representation of RASIM as well as directing analysts to representative texts in order to carry out qualitative analysis. The article suggests a framework for adopting corpus approaches in critical discourse analysis.
1,208 citations
TL;DR: It is proposed that a trait-based approach will help to develop strategies to preserve and promote carbon sequestration under global changes, and how the composition of key plant traits and soil biota related to carbon input, release and storage prevail in different biomes across the globe.
Abstract: Plant functional traits control a variety of terrestrial ecosystem processes, including soil carbon storage which is a key component of the global carbon cycle. Plant traits regulate net soil carbon storage by controlling carbon assimilation, its transfer and storage in belowground biomass, and its release from soil through respiration, fire and leaching. However, our mechanistic understanding of these processes is incomplete. Here, we present a mechanistic framework, based on the plant traits that drive soil carbon inputs and outputs, for understanding how alteration of vegetation composition will affect soil carbon sequestration under global changes. First, we show direct and indirect plant trait effects on soil carbon input and output through autotrophs and heterotrophs, and through modification of abiotic conditions, which need to be considered to determine the local carbon sequestration potential. Second, we explore how the composition of key plant traits and soil biota related to carbon input, release and storage prevail in different biomes across the globe, and address the biome-specific mechanisms by which plant trait composition may impact on soil carbon sequestration. We propose that a trait-based approach will help to develop strategies to preserve and promote carbon sequestration.
1,141 citations
TL;DR: The TPSN framework as mentioned in this paper proposes that territories (T), places (P), scales (S), and networks (N) must be viewed as mutually constitutive and relationally intertwined dimensions of sociospatial relations.
Abstract: This essay seeks to reframe recent debates on sociospatial theory through the introduction of an approach that can grasp the inherently polymorphic, multidimensional character of sociospatial relations. As previous advocates of a scalar turn, we now question the privileging, in any form, of a single dimension of sociospatial processes, scalar or otherwise. We consider several recent sophisti- cated 'turns' within critical social science; explore their methodological limitations; and highlight several important strands of sociospatial theory that seek to transcend the latter. On this basis, we argue for a more systematic recognition of polymorphythe organization of sociospatial relations in multiple formswithin sociospatial theory. Specifically, we suggest that territories (T), places (P), scales (S), and networks (N) must be viewed as mutually constitutive and relationally intertwined dimensions of sociospatial relations. We present this proposition as an extension of recent contribu- tions to the spatialization of the strategic-relational approach (SRA), and we explore some of its methodological implications. We conclude by briefly illustrating the applicability of the 'TPSN framework' to several realms of inquiry into sociospatial processes under contemporary capitalism.
915 citations
TL;DR: In this paper, the authors investigated the relationship of seven work-related stressors with job performance: role ambiguity, role conflict, role overload, job insecurity, work-family conflict, environmental uncertainty, and situational constraints.
Abstract: We quantitatively integrated 169 samples (N= 35,265 employees) that have been used to investigate the relationships of the following 7 work-related stressors with job performance: role ambiguity, role conflict, role overload, job insecurity, work–family conflict, environmental uncertainty, and situational constraints. Overall, we obtained a negative mean correlation between each job performance measure and each stressor included in our analyses. As hypothesized, role ambiguity and situational constraints were most strongly negatively related to performance, relative to the other work-related stressors. Analysis of moderators revealed that (a) the negative correlation of role overload and performance was higher among managers relative to nonmanagers; (b) publication year moderated the relation of role ambiguity and role overload with performance, although in opposite directions; (c) the correlations obtained for published versus unpublished studies were not significantly different; and (d) using the Rizzo et al. scale of role ambiguity and role conflict decreased the magnitude of the correlations of these stressors with performance, relative to other scales. Theoretical contributions, future research directions, and practical implications are discussed.
886 citations
TL;DR: To understand the potential negative and positive contributions of soil microbes to land–atmosphere carbon exchange and global warming requires explicit consideration of both direct and indirect impacts of climate change on microorganisms.
Abstract: There is considerable interest in understanding the biological mechanisms that regulate carbon exchanges between the land and atmosphere, and how these exchanges respond to climate change. An understanding of soil microbial ecology is central to our ability to assess terrestrial carbon cycle–climate feedbacks, but the complexity of the soil microbial community and the many ways that it can be affected by climate and other global changes hampers our ability to draw firm conclusions on this topic. In this paper, we argue that to understand the potential negative and positive contributions of soil microbes to land–atmosphere carbon exchange and global warming requires explicit consideration of both direct and indirect impacts of climate change on microorganisms. Moreover, we argue that this requires consideration of complex interactions and feedbacks that occur between microbes, plants and their physical environment in the context of climate change, and the influence of other global changes which have the capacity to amplify climate-driven effects on soil microbes. Overall, we emphasize the urgent need for greater understanding of how soil microbial ecology contributes to land–atmosphere carbon exchange in the context of climate change, and identify some challenges for the future. In particular, we highlight the need for a multifactor experimental approach to understand how soil microbes and their activities respond to climate change and consequences for carbon cycle feedbacks.
884 citations
TL;DR: In this paper, the authors present a theoretical framework for inter-organizational knowledge transfer and identify key themes covered by the six articles included in the Special Issue on Inter-Organizational Knowledge Transfer, and then discuss priorities for future research.
Abstract: Many papers have been published recently in the fields of strategy and international business research incorporating the role of organizational knowledge as a basis of firm competitive advantage. While such knowledge is normally developed within the firm, it is important that firms possess the ability to learn from others in order to meet the increasing pace of competition. Knowledge transfer, defined here as an event through which one organization learns from the experience of another, has thus become an important research area within the broader domain of organizational learning and knowledge management. This paper presents a theoretical framework, identifies key themes covered by the six articles included in the Special Issue on Inter-Organizational Knowledge Transfer, and then discusses priorities for future research.
817 citations
TL;DR: The challenge for palliative care in the 21st century is to develop models and coverage appropriate to those in need, whatever their diagnosis, income or setting without losing the original principles of the hospice movement.
759 citations
TL;DR: In this paper, the authors consider the way in which community has become attached to renewable energy projects in the UK, both in grassroot action and in mainstream energy policy, and identify a diversity of understandings and interpretations that revolve around questions of both process and outcome.
746 citations
TL;DR: It is demonstrated that plant functional complementarity is a key reason why higher plant diversity leads to greater soil C and N accumulation on agriculturally degraded soils and suggested the combination of key C4 grass‐legume species may greatly increase ecosystem services such as soil C accumulation and biomass (biofuel) production in both high- and low-diversity N-limited grassland systems.
Abstract: Summary 1. The mechanisms controlling soil carbon (C) and nitrogen (N) accumulation are crucial for explaining why soils are major terrestrial C sinks. Such mechanisms have been mainly addressed by imposing short-term, step-changes in CO 2 , temperature and N fertilization rates on either monocultures or low-diversity plant assemblages. No studies have addressed the long-term effects of plant functional diversity (i.e. plant functional composition) on rates of soil C accumulation in N-limited grasslands where fixation is the main source of N for plants. 2. Here we measure net soil C and N accumulation to 1 m soil-depth during a 12-year-long grassland biodiversity experiment established on agriculturally degraded soils at Cedar Creek, Minnesota, USA. 3. We show that high-diversity mixtures of perennial grassland plant species stored 500% and 600% more soil C and N than, on average, did monoculture plots of the same species. Moreover, the presence of C4 grasses and legumes increased soil C accumulation by 193% and 522%, respectively. Higher soil C and N accrual resulted both from increased C and N inputs via (i) higher root biomass, and (ii) from greater root biomass accumulation to 60 cm soil depth resulting from the presence of highly complementary functional groups (i.e. C4 grasses and legumes). 4. Our results suggest that the joint presence of C4 grass and legume species is a key cause of greater soil C and N accumulation in both higher and lower diversity plant assemblages. This is because legumes have unique access to N, and C4 grasses take up and use N efficiently, increasing below-ground biomass and thus soil C and N inputs. 5. Synthesis. We demonstrate that plant functional complementarity is a key reason why higher plant diversity leads to greater soil C and N accumulation on agriculturally degraded soils. We suggest the combination of key C4 grass‐legume species may greatly increase ecosystem services such as soil C accumulation and biomass (biofuel) production in both high- and low-diversity N-limited grassland systems.
TL;DR: It is argued that there is a link between the role of dynamic capabilities, and the firm's abilities for knowledge management, which has not been fully articulated in the literature.
Abstract: Modern strategic management theories try to explain why firms differ, because new sources of competitive advantage are keenly sought in the dynamic and complex environment of global competition. Two areas in particular have attracted the attention of researchers: the role of dynamic capabilities, and the firm's abilities for knowledge management. In this paper, we argue that there is a link between these two concepts, which has not been fully articulated in the literature. The aim of the paper is therefore to ascertain the conceptual connection between them as a basis for future research. Our proposed framework acknowledges and critiques the distinct roots of each field, identifies boundaries, and proposes relationships between the constructs and firm performance.
TL;DR: Although more than half of the world's countries have a palliative care service, many countries still have no provision, and major increases are needed before palliatives care is generally accessible worldwide.
TL;DR: Improved knowledge of plant–microbe interactions and the interaction between epiphytic and immigrant micro‐organisms on the leaf surface will lead to novel methods to limit enteropathogen survival in the phyllosphere.
Abstract: Consumption of fruit and vegetable products is commonly viewed as a potential risk factor for infection with enteropathogens such as Salmonella and Escherichia coli O157, with recent outbreaks linked to lettuce, spinach and tomatoes. Routes of contamination are varied and include application of organic wastes to agricultural land as fertilizer, contamination of waters used for irrigation with faecal material, direct contamination by livestock, wild animals and birds and postharvest issues such as worker hygiene. The ability of pathogens to survive in the field environment has been well studied, leading to the implementation of guidelines such as the Safe Sludge Matrix, which aim to limit the likelihood of viable pathogens remaining at point-of-sale. The behaviour of enteropathogens in the phyllosphere is a growing field of research, and it is suggested that inclusion in phyllosphere biofilms or internalization within the plant augments the survival. Improved knowledge of plant-microbe interactions and the interaction between epiphytic and immigrant micro-organisms on the leaf surface will lead to novel methods to limit enteropathogen survival in the phyllosphere.
Natural Environment Research Council1, European Bioinformatics Institute2, Wellcome Trust Sanger Institute3, University of Cambridge4, Stanford University5, Swiss Institute of Bioinformatics6, University of British Columbia7, Livestrong Foundation8, Institute for Systems Biology9, University of California, Davis10, Lockheed Martin Corporation11, University of Edinburgh12, Newcastle University13, Medical Research Council14, Aberystwyth University15, National Science Foundation16, Beilstein-Institut17, National Institutes of Health18, Boston Children's Hospital19, Norwegian University of Science and Technology20, University of Georgia21, University of California, Berkeley22, University of Texas Southwestern Medical Center23, Lancaster University24, German Cancer Research Center25, University of Manchester26, Harvard University27, Iowa State University28, Bristol-Myers Squibb29, University at Buffalo30, AstraZeneca31, Trinity College, Dublin32, Wageningen University and Research Centre33, Ghent University34
TL;DR: The Minimum Information for Biological and Biomedical Investigations (MIBBI) project aims to foster the coordinated development of minimum-information checklists and provide a resource for those exploring the range of extant checklists.
Abstract: The Minimum Information for Biological and Biomedical Investigations (MIBBI) project aims to foster the coordinated development of minimum-information checklists and provide a resource for those exploring the range of extant checklists.
TL;DR: This work presents a generic and novel framework for identifying high-performance indicator taxa that combine practical feasibility and ecological value, and illustrates the approach using a large-scale assessment of 14 different higher taxa across three forest types in the Brazilian Amazon.
Abstract: The identification of high-performance indicator taxa that combine practical feasibility and ecological value requires an understanding of the costs and benefits of surveying different taxa. We present a generic and novel framework for identifying such taxa, and illustrate our approach using a large-scale assessment of 14 different higher taxa across three forest types in the Brazilian Amazon, estimating both the standardized survey cost and the ecological and biodiversity indicator value for each taxon. Survey costs varied by three orders of magnitude, and dung beetles and birds were identified as especially suitable for evaluating and monitoring the ecological consequences of habitat change in our study region. However, an exclusive focus on such taxa occurs at the expense of understanding patterns of diversity in other groups. To improve the cost-effectiveness of biodiversity research we encourage a combination of clearer research goals and the use of an objective evidence-based approach to selecting study taxa.
TL;DR: The combination of the key words and key domains methods is shown to allow macroscopic analysis to inform the microscopic level (focussing on the use of a particular linguistic feature) and thereby suggesting those linguistic features which should be investigated further.
Abstract: This paper reports the extension of the key words method for the comparison of corpora. Using automatic tagging software that assigns part-of-speech and semantic field (domain) tags, a method is described which permits the extraction of key domains by applying the keyness calculation to tag frequency lists. The combination of the key words and key domains methods is shown to allow macroscopic analysis (the study of the characteristics of whole texts or varieties of language) to inform the microscopic level (focussing on the use of a particular linguistic feature) and thereby suggesting those linguistic features which should be investigated further. The resulting 'data-driven' approach presented here combines elements of both the 'corpus-based' and 'corpus-driven' paradigms in corpus linguistics. A web-based tool, Wmatrix, implementing the proposed method is applied in a case study: the comparison of UK 2001 general election manifestos of the Labour and Liberal Democratic parties.
TL;DR: In this paper, the authors derived big-bang nucleosynthesis (BBN) constraints on both unstable and stable gravitino taking account of recent progress in theoretical study of the BBN processes as well as observations of primordial light-element abundances.
Abstract: We derive big-bang nucleosynthesis (BBN) constraints on both unstable and stable gravitino taking account of recent progress in theoretical study of the BBN processes as well as observations of primordial light-element abundances In the case of unstable gravitino, we set the upper limit on the reheating temperature assuming that the primordial gravitinos are mainly produced by the scattering processes of thermal particles For stable gravitino, we consider B-ino, stau, and sneutrino as the next-to-the-lightest supersymmetric particle and obtain constraints on their properties Compared with the previous works, we improved the following points: (i) we use the most recent observational data, (ii) for gravitino production, we include contribution of the longitudinal component, and (iii) for the case with unstable long-lived stau, we estimate the bound-state effect of stau accurately by solving the Boltzmann equation
TL;DR: This paper examined the discursive construction of refugees and asylum seekers in a 140 million-word corpus of UK press articles published between 1996 and 2005, and pointed out negative categories of representation, the existence and development of nonsensical terms (e.g., illegal refugee), and media confusion and conflation of definitions of the four terms under examination.
Abstract: This paper examines the discursive construction of refugees and asylum seekers (and to a lesser extent immigrants and migrants) in a 140-million-word corpus of UK press articles published between 1996 and 2005. Taking a corpus-based approach, the data were analyzed not only as a whole, but also with regard to synchronic variation, by carrying out concordance analyses of keywords which occurred within tabloid and broad-sheet newspapers, and diachronic change, albeit mainly approached from an unusual angle, by investigating consistent collocates and frequencies of specific terms over time. The analyses point to a number of (mainly negative) categories of representation, the existence and development of nonsensical terms (e.g., illegal refugee), and media confusion and conflation of definitions of the four terms under examination. The paper concludes by critically discussing the extent to which a corpus-based methodological stance can inform critical discourse analysis.
Book•
International Institute for Applied Systems Analysis1, University of London2, University of York3, University of Exeter4, Peninsula College5, University of Plymouth6, University of Birmingham7, Imperial College London8, King's College London9, Lancaster University10, Norwegian Meteorological Institute11, University of East Anglia12, University of Leeds13, University of Cambridge14, University of Reading15
TL;DR: It is shown, based on measurements in high magnetic fields, that defects are the dominant source of light from Si nanocrystals, and it is shown that it is possible to control the origin of the photoluminescence in a single sample.
Abstract: Silicon dominates the electronics industry, but its poor optical properties mean that III–V compound semiconductors are preferred for photonics applications. Photoluminescence at visible wavelengths was observed from porous Si at room temperature in 1990, but the origin of these photons (do they arise from highly localized defect states or quantum confinement effects?) has been the subject of intense debate ever since. Attention has subsequently shifted from porous Si to Si nanocrystals, but the same fundamental question about the origin of the photoluminescence has remained. Here we show, based on measurements in high magnetic fields, that defects are the dominant source of light from Si nanocrystals. Moreover, we show that it is possible to control the origin of the photoluminescence in a single sample: passivation with hydrogen removes the defects, resulting in photoluminescence from quantum-confined states, but subsequent ultraviolet illumination reintroduces the defects, making them the origin of the light again.
TL;DR: In this article, a broad view is taken of what the meaning of community-owned production and use might constitute, as there are different models of community ownership, different notions of community and different degrees of connection or disconnection between produce and use.
TL;DR: Countries must learn how to capitalize on their citizens' cognitive resources if they are to prosper, both economically and socially, according to the World Bank.
Abstract: Countries must learn how to capitalize on their citizens' cognitive resources if they are to prosper, both economically and socially. Early interventions will be key.
TL;DR: The SMQ has a single factor structure, was internally reliable, significantly correlated with the MAAS, showed expected associations with affect, and distinguished among meditators, non-meditators and people with psychosis.
Abstract: Objective. To assess the reliability and validity of the Southampton mindfulness questionnaire (SMQ), a 16-item measure of mindful awareness of distressing thoughts and images. Methods. A total of 256 people participated, comprising a non-clinical community sample of 134 (83 meditators and 51 non-meditators) and a clinical sample of 122 people with a current distressing psychosis. To assess concurrent validity, non-clinical participants and half clinical participants (total 197 participants) completed the mindful attention awareness scale (MAAS). Predicted links were assessed with affect, and 59 patients completed a validated measure to assess link between mindfulness and intensity of 'delusional' experience. Results. The scale has a single factor structure, was internally reliable, significantly correlated with the MAAS, showed expected associations with affect, and distinguished among meditators, non-meditators and people with psychosis. Conclusions. The data support use of the SMQ in clinical practice and research to assess mindful responding to distressing thoughts and images.
TL;DR: The novel population genetics approach reveals that the vast majority (97%) of sporadic disease can be attributed to animals farmed for meat and poultry, whereas wild animal and environmental sources are responsible for just 3% of disease.
Abstract: Campylobacter jejuni is the leading cause of bacterial gastro-enteritis in the developed world. It is thought to infect 2–3 million people a year in the US alone, at a cost to the economy in excess of US $4 billion. C. jejuni is a widespread zoonotic pathogen that is carried by animals farmed for meat and poultry. A connection with contaminated food is recognized, but C. jejuni is also commonly found in wild animals and water sources. Phylogenetic studies have suggested that genotypes pathogenic to humans bear greatest resemblance to non-livestock isolates. Moreover, seasonal variation in campylobacteriosis bears the hallmarks of water-borne disease, and certain outbreaks have been attributed to contamination of drinking water. As a result, the relative importance of these reservoirs to human disease is controversial. We use multilocus sequence typing to genotype 1,231 cases of C. jejuni isolated from patients in Lancashire, England. By modeling the DNA sequence evolution and zoonotic transmission of C. jejuni between host species and the environment, we assign human cases probabilistically to source populations. Our novel population genetics approach reveals that the vast majority (97%) of sporadic disease can be attributed to animals farmed for meat and poultry. Chicken and cattle are the principal sources of C. jejuni pathogenic to humans, whereas wild animal and environmental sources are responsible for just 3% of disease. Our results imply that the primary transmission route is through the food chain, and suggest that incidence could be dramatically reduced by enhanced on-farm biosecurity or preventing food-borne transmission.
TL;DR: The auxin/cytokinin ratio in the leaves and roots may explain both the salinity-induced decrease in shoot vigour and the shift in biomass allocation to the roots, in agreement with changes in the activity of the sink-related enzyme cell wall invertase.
Abstract: Following exposure to salinity, the root/shoot ratio is increased (an important adaptive response) due to the rapid inhibition of shoot growth (which limits plant productivity) while root growth is maintained. Both processes may be regulated by changes in plant hormone concentrations. Tomato plants (Solanum lycopersicum L. cv Moneymaker) were cultivated hydroponically for 3 weeks under high salinity (100 mM NaCl) and five major plant hormones (abscisic acid, ABA; the cytokinins zeatin, Z, and zeatin-riboside, ZR; the auxin indole-3-acetic acid, IAA; and the ethylene precursor 1-aminocyclopropane-1-carboxylic acid, ACC) were determined weekly in roots, xylem sap, and leaves. Salinity reduced shoot biomass by 50-60% and photosynthetic area by 20-25% both by decreasing leaf expansion and delaying leaf appearance, while root growth was less affected, thus increasing the root/shoot ratio. ABA and ACC concentrations strongly increased in roots, xylem sap, and leaves after 1 d (ABA) and 15 d (ACC) of salinization. By contrast, cytokinins and IAA were differentially affected in roots and shoots. Salinity dramatically decreased the Z+ZR content of the plant, and induced the conversion of ZR into Z, especially in the roots, which accounted for the relative increase of cytokinins in the roots compared to the leaf. IAA concentration was also strongly decreased in the leaves while it accumulated in the roots. Decreased cytokinin content and its transport from the root to the shoot were probably induced by the basipetal transport of auxin from the shoot to the root. The auxin/cytokinin ratio in the leaves and roots may explain both the salinity-induced decrease in shoot vigour (leaf growth and leaf number) and the shift in biomass allocation to the roots, in agreement with changes in the activity of the sink-related enzyme cell wall invertase.
TL;DR: This article argues for the benefits and feasibility of a generic yet tailorable approach to component-based systems-building that offers a uniform programming model that is applicable in a wide range of systems-oriented target domains and deployment environments.
Abstract: Component-based software structuring principles are now commonplace at the application level; but componentization is far less established when it comes to building low-level systems software. Although there have been pioneering efforts in applying componentization to systems-building, these efforts have tended to target specific application domains (e.g., embedded systems, operating systems, communications systems, programmable networking environments, or middleware platforms). They also tend to be targeted at specific deployment environments (e.g., standard personal computer (PC) environments, network processors, or microcontrollers). The disadvantage of this narrow targeting is that it fails to maximize the genericity and abstraction potential of the component approach. In this article, we argue for the benefits and feasibility of a generic yet tailorable approach to component-based systems-building that offers a uniform programming model that is applicable in a wide range of systems-oriented target domains and deployment environments. The component model, called OpenCom, is supported by a reflective runtime architecture that is itself built from components. After describing OpenCom and evaluating its performance and overhead characteristics, we present and evaluate two case studies of systems we have built using OpenCom technology, thus illustrating its benefits and its general applicability.
Goddard Institute for Space Studies1, Goddard Space Flight Center2, University of Edinburgh3, Geophysical Fluid Dynamics Laboratory4, National Center for Atmospheric Research5, Met Office6, Forschungszentrum Jülich7, Lancaster University8, Lawrence Livermore National Laboratory9, École Polytechnique Fédérale de Lausanne10, University of Maryland, Baltimore County11, Norwegian Meteorological Institute12, York University13, Seoul National University14, Max Planck Society15, Kyushu University16, University of Cambridge17, United States Environmental Protection Agency18
TL;DR: This paper examined the response of Arctic gas and aerosol concentrations to perturbations in pollutant emissions from Europe, East and South Asia, and North America using re-sults from a coordinated model intercomparison.
Abstract: We examine the response of Arctic gas and aerosol concentrations to perturbations in pollutant emissions from Europe, East and South Asia, and North America using re- sults from a coordinated model intercomparison. These sen- sitivities to regional emissions (mixing ratio change per unit emission) vary widely across models and species. Intermodel differences are systematic, however, so that the relative im- portance of different regions is robust. North America con- tributes the most to Arctic ozone pollution. For aerosols
TL;DR: In this paper, the authors present an extensive empirical investigation into network transformation over time, using three longitudinal case studies of entrepreneurs operating in the oil industry in the North East of Scotland, and demonstrate that networks are vital living organisms, changing, growing and developing over time.
Abstract: Although it is now well established that networks contribute to entrepreneurship by extending the individual entrepreneurial asset base of human, social, market, financial and technical capacity, little work, empirical or theoretical, has examined the dynamics of networking processes in a temporal framework. Drawing on evidence from three longitudinal case studies of entrepreneurs operating in the oil industry in the North East of Scotland, this paper presents an extensive empirical investigation into network transformation over time. We are thus able to chart networks in their historical contingency. This chronological lens allows us to view patterns in network continuity and change and enables us to develop a rich conceptual framework. The study demonstrates that networks are vital living organisms, changing, growing and developing over time. Yet set in their history, networks are much more than an extension of the entrepreneurial asset base. Our data shows how a reconceptualization of the nature of net...
TL;DR: The paper identifies instruments, provides examples of their use, and describes how synergy between measurement and modelling could be achieved, and provides a vision for the use of electrical and magnetic geophysical instrumentation in watershed scale hydrology.
Abstract: We want to develop a dialogue between geophysicists and hydrologists interested in synergistically advancing process based watershed research. We identify recent advances in geophysical instrumentation, and provide a vision for the use of electrical and magnetic geophysical instrumentation in watershed scale hydrology. The focus of the paper is to identify instrumentation that could significantly advance this vision for geophysics and hydrology during the next 3–5 years. We acknowledge that this is one of a number of possible ways forward and seek only to offer a relatively narrow and achievable vision. The vision focuses on the measurement of geological structure and identification of flow paths using electrical and magnetic methods. The paper identifies instruments, provides examples of their use, and describes how synergy between measurement and modelling could be achieved. Of specific interest are the airborne systems that can cover large areas and are appropriate for watershed studies. Although airborne geophysics has been around for some time, only in the last few years have systems designed exclusively for hydrological applications begun to emerge. These systems, such as airborne electromagnetic (EM) and transient electromagnetic (TEM), could revolutionize hydrogeological interpretations. Our vision centers on developing nested and cross scale electrical and magnetic measurements that can be used to construct a three-dimensional (3D) electrical or magnetic model of the subsurface in watersheds. The methodological framework assumes a ‘top down’ approach using airborne methods to identify the large scale, dominant architecture of the subsurface. We recognize that the integration of geophysical measurement methods, and data, into watershed process characterization and modelling can only be achieved through dialogue. Especially, through the development of partnerships between geophysicists and hydrologists, partnerships that explore how the application of geophysics can answer critical hydrological science questions, and conversely provide an understanding of the limitations of geophysical measurements and interpretation. Copyright © 2008 John Wiley & Sons, Ltd.