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Environmental Sensitivity (environmental + sensitivity)
Selected AbstractsDevelopment and characterization of a fusion protein between thermally responsive elastin-like polypeptide and interleukin-1 receptor antagonist: Sustained release of a local antiinflammatory therapeuticARTHRITIS & RHEUMATISM, Issue 11 2007Mohammed F. Shamji Objective Interleukin-1 receptor antagonist (IL-1Ra) has been evaluated for the intraarticular treatment of osteoarthritis. Such administration of proteins may have limited utility because of their rapid clearance and short half-life in the joint. The fusion of a drug to elastin-like polypeptides (ELPs) promotes the formation of aggregating particles that form a "drug depot" at physiologic temperatures, a phenomenon intended to prolong the presence of the drug. The purpose of this study was to develop an injectable drug depot composed of IL-1Ra and ELP domains and to evaluate the properties and bioactivity of the recombinant ELP-IL-1Ra fusion protein. Methods Fusion proteins between IL-1Ra and 2 distinct sequences and molecular weights of ELP were overexpressed in Escherichia coli. Environmental sensitivity was demonstrated by turbidity and dynamic light scattering as a function of temperature. IL-1Ra domain activity was evaluated by surface plasmon resonance, and in vitro antagonism of IL-1,mediated lymphocyte and thymocyte proliferation, as well as IL-1,induced tumor necrosis factor , (TNF,) expression and matrix metalloproteinase 3 (MMP-3) and ADAMTS-4 messenger RNA expression in human intervertebral disc fibrochondrocytes. IL-1Ra immunoreactivity was assessed before and after proteolytic degradation of the ELP partner. Results Both fusion proteins underwent supramolecular aggregation at subphysiologic temperatures and slowly resolubilized at 37°C. Interaction with IL-1 receptor was slower in association but equivalent in dissociation as compared with the commercial antagonist. Anti,IL-1 activity was demonstrated by inhibition of lymphocyte and thymocyte proliferation and by decreased TNF, expression and ADAMTS-4 and MMP-3 transcription by fibrochondrocytes. ELP domain proteolysis liberated a peptide of comparable size and immunoreactivity as the commercial IL-1Ra. This peptide was more bioactive against lymphocyte proliferation, nearly equivalent to the commercial antagonist. Conclusion The ELP-IL-1Ra fusion protein proved to retain the characteristic ELP inverse phase-transitioning behavior as well as the bioactivity of the IL-1Ra domain. This technology represents a novel drug carrier designed to prolong the presence of bioactive peptides following intraarticular delivery. [source] Intra- and intersectoral effects in environmental disclosures: evidence for legitimacy theory?BUSINESS STRATEGY AND THE ENVIRONMENT, Issue 6 2003David Campbell Environmental disclosures were recorded from the annual reports of a sample of ten UK FTSE 100 companies in five sectors between 1974 and 2000. ,Environmental sensitivity' was employed as a proxy for corporate vulnerability to environmental concern, and intra- and intersectoral differences were tested for in the belief that difference in industry response will signify differing perceptions on the need to provide voluntary disclosure and hence restore or maintain legitimacy. Intrasectoral agreements at given points in time were also taken to be evidence for legitimacy theory in that more than one company in a sector perceived a need to change disclosure behaviour at the same time. Legitimacy theory as an explicator for variability in environmental disclosure is supported. Copyright © 2003 John Wiley & Sons, Ltd and ERP Environment. [source] Can mechanism inform species' distribution models?ECOLOGY LETTERS, Issue 8 2010Lauren B. Buckley Ecology Letters (2010) 13: 1041,1054 Abstract Two major approaches address the need to predict species distributions in response to environmental changes. Correlative models estimate parameters phenomenologically by relating current distributions to environmental conditions. By contrast, mechanistic models incorporate explicit relationships between environmental conditions and organismal performance, estimated independently of current distributions. Mechanistic approaches include models that translate environmental conditions into biologically relevant metrics (e.g. potential duration of activity), models that capture environmental sensitivities of survivorship and fecundity, and models that use energetics to link environmental conditions and demography. We compared how two correlative and three mechanistic models predicted the ranges of two species: a skipper butterfly (Atalopedes campestris) and a fence lizard (Sceloporus undulatus). Correlative and mechanistic models performed similarly in predicting current distributions, but mechanistic models predicted larger range shifts in response to climate change. Although mechanistic models theoretically should provide more accurate distribution predictions, there is much potential for improving their flexibility and performance. [source] Identifiability of parameters and behaviour of MCMC chains: a case study using the reaction norm modelJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 2 2009M.M. Shariati Summary Markov chain Monte Carlo (MCMC) enables fitting complex hierarchical models that may adequately reflect the process of data generation. Some of these models may contain more parameters than can be uniquely inferred from the distribution of the data, causing non-identifiability. The reaction norm model with unknown covariates (RNUC) is a model in which unknown environmental effects can be inferred jointly with the remaining parameters. The problem of identifiability of parameters at the level of the likelihood and the associated behaviour of MCMC chains were discussed using the RNUC as an example. It was shown theoretically that when environmental effects (covariates) are considered as random effects, estimable functions of the fixed effects, (co)variance components and genetic effects are identifiable as well as the environmental effects. When the environmental effects are treated as fixed and there are other fixed factors in the model, the contrasts involving environmental effects, the variance of environmental sensitivities (genetic slopes) and the residual variance are the only identifiable parameters. These different identifiability scenarios were generated by changing the formulation of the model and the structure of the data and the models were then implemented via MCMC. The output of MCMC sampling schemes was interpreted in the light of the theoretical findings. The erratic behaviour of the MCMC chains was shown to be associated with identifiability problems in the likelihood, despite propriety of posterior distributions, achieved by arbitrarily chosen uniform (bounded) priors. In some cases, very long chains were needed before the pattern of behaviour of the chain may signal the existence of problems. The paper serves as a warning concerning the implementation of complex models where identifiability problems can be difficult to detect a priori. We conclude that it would be good practice to experiment with a proposed model and to understand its features before embarking on a full MCMC implementation. [source] An exploration of corporate attitudes to the significance of environmental information for stakeholdersCORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 4 2003David Collison This paper reports on a questionnaire survey sent to environmental managers in quoted UK firms from environmentally sensitive sectors. A total of 58 usable responses was received, with most but not all being returned by environmental managers. While contextual information regarding perceptions of their companies' environmental sensitivity and management systems was sought, the main focus of the questionnaire was on respondents' views about stakeholder concerns. There was broad agreement that external stakeholders attached importance to environmental communications. The results indicate that respondents' perceptions of these issues were associated with the formality of their internal management systems and with the role of the respondents within their firms. It was also found that shareholders were thought to be the least interested stakeholder group. Copyright © 2003 John Wiley & Sons, Ltd and ERP Environment. [source] The sedimentary records in Mediterranean rockshelters and caves: Archives of environmental changeGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 4 2001Jamie C. Woodward It is important to develop rigorous methods and robust conceptual models for the interpretation of rockshelter and cave sediment records so that the cultural sequences they contain can be considered in their proper environmental context. Much of what we know about the prehistory of the Mediterranean region and adjacent areas has largely been pieced together from materials excavated from sedimentary sequences in these environments. The rockshelters and caves of the region form important environmental and sedimentary archives. Recent work has begun to consider if the remarkable climatic variability evident in the high resolution lacustrine and ice core records is manifest in the rockshelter and cave sediment records of the area. In this context, the two main characteristics of a rockshelter or cave site which control its usefulness as an archive of environmental change are the temporal resolution of the sedimentary record and the environmental sensitivity of the site. Many rockshelters and caves can be described as either Active Karst Settings (AKS) or Passive Karst Settings (PKS) and site type is an important influence on climatic sensitivity with a direct influence upon the usefulness of the sedimentary sequence as a proxy record of climate change. It is now clear that some sites may preserve detailed paleoclimatic records and the climatic signal may be represented by distinctive suites of micromorphological features, by variations in the input of allogenic sediment, or by fluctuations in the mineral magnetic properties of the fine sediment fraction. It can be argued that data derived from the analysis of bulk coarse-grained samples often lacks the stratigraphic resolution and environmental sensitivity that can be obtained from other approaches. The most favorable sites for detailed paleoclimatic reconstruction appear to be in active karst settings such as Theopetra Cave (Greece) and Pigeon Cave (Morocco) where micromorphological analyses offer insights into the stratigraphic record that are not otherwise obtainable. The temporal resolution of a site can only be established through a rigorous stratigraphic analysis and a comprehensive dating program. These are fundamental considerations in the study of rockshelter sediment records, especially when attempting to correlate between sites and draw comparisons with other proxy records of environmental change derived from sedimentary environments with rather different characteristics. Rockshelters and caves are part of a wider sediment system, and their investigation must be accompanied by detailed geomorphological, sedimentological, paleoecological, and geochronological studies of the off-site Quaternary record. © 2001 John Wiley & Sons, Inc. [source] The New Mega-Projects: Genesis and ImpactsINTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 4 2008FERNANDO DIAZ ORUETA Abstract Critiques of urban renewal and large-scale developments were prominent in the period 1960,80. In particular, they emphasized the negative environmental and social consequences of these schemes and especially attacked them for displacing low-income and ethnically different populations. In the 1980s and 1990s, we saw a decline in such projects in many places, responding to popular protest and intellectual dissent, along with a new emphasis on preservation. More recently, however, we see the revival of mega-projects, often connected with tourism and sports development and incorporating the designs of world-famous architects. Frequently these are on landfill or abandoned industrial sites. The symposium for which this is an introduction shows the growing convergence of North American and European projects. This convergence is visible in their physical form, their financing, and in the role played by the state in a world marked by neoliberalism. At the same time, the new projects do display a greater environmental sensitivity and commitment to urbanity than the modernist schemes of an earlier epoch. Résumé Dans la période 1960,1980, les critiques sur les aménagements à grande échelle et les grandes rénovations urbaines étaient fréquentes. Elles soulignaient notamment les conséquences environnementales et sociales néfastes de ces programmes, en leur reprochant en particulier de déplacer les populations à faible revenu ou d'appartenance ethnique différente. Dans les années 1980 et 1990, ces projets se sont faits plus rares dans bien des endroits, répondant à la contestation populaire et au désaccord des intellectuels, parallèlement à une préoccupation nouvelle pour la préservation. Dernièrement, pourtant, les mégaprojets ont réapparu, souvent associés à un aménagement touristique ou sportif et intégrant des créations d'architectes de renommée mondiale. Ils se situent fréquemment sur le site d'anciennes décharges ou usines abandonnées. Le symposium dont ce texte sert d'introduction montre la convergence croissante des projets nord-américains et européens, convergence que l'on constate dans leur forme physique, leur financement et dans le rôle que joue l'État dans un monde empreint de néolibéralisme. En même temps, les nouveaux projets affichent une sensibilitéà l'environnement et un engagement vis-à-vis de l'urbanité plus marqués que les programmes modernistes antérieurs. [source] Antimicrobial peptide interactions with silica bead supported bilayers and E. coli: buforin II, magainin II, and arenicin,JOURNAL OF PEPTIDE SCIENCE, Issue 8 2009Ryan W. Davis Abstract Using the unique quantitative capabilities of hyperspectral confocal microscopy combined with multivariate curve resolution, a comparative approach was employed to gain a deeper understanding of the different types of interactions of antimicrobial peptides (AMPs) with biological membranes and cellular compartments. This approach allowed direct comparison of the dynamics and local effects of buforin II, magainin II, and arenicin with nanoporous silica bead supported bilayers and living E. coli. Correlating between experiments and comparing these responses have yielded several important discoveries for pursuing the underlying biophysics of bacteriocidal specificity and the connection between structure and function in various cellular environments. First, a novel fluorescence method for direct comparison of a model and living system is demonstrated by utilizing the membrane partitioning and environmental sensitivity of propidium iodide. Second, measurements are presented comparing the temporal dynamics and local equilibrium concentrations of the different antimicrobial agents in the membrane and internal matrix of the described systems. Finally, we discuss how the data lead to a deeper understanding of the roles of membrane penetration and permeabilization in the action of these AMPs. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd. [source] Mapping sensitivity to land degradation in Extremadura.LAND DEGRADATION AND DEVELOPMENT, Issue 2 2009SW Spain Abstract An assessment of sensitivity to land degradation has been carried out in the Extremadura region, SW Spain, by means of a modelling approach developed by the European Commission funded MEDALUS project (Mediterranean Desertification and Land Use) which identifies such areas on the basis of an index (Environmentally Sensitive Area index, ESA index) that incorporates data on environmental quality (climate, vegetation, soil) as well as anthropogenic factors (management). Two maps of environmental sensitivity (ES) to degradation with different legend resolution (four and eight classes of sensitivity) have been made and tested by comparing classes of the legends with an extensive number (2690) of true field data gathered from plots distributed all over the study region. Independent variables of validation consisted of nine degradation-related types of data and the method tested the performance of the whole model and the statistical separability among classes of sensitivity, as well as the capability of the variables in delimiting the classes. Results showed a good performance of the whole model to both, the map of four and eighth classes of sensitivity. Separation among classes of sensitivity showed a slightly different behaviour of both maps, identifying transitional classes in the map of eight classes where classification could be improved in terms of the ranges of ESA index values assigned to the different classes. Copyright © 2008 John Wiley & Sons, Ltd. [source] Population in the UN Environment Programme's Global Environment Outlook 2000POPULATION AND DEVELOPMENT REVIEW, Issue 3 2000Article first published online: 27 JAN 200 Most specialized agencies in the United Nations system have taken to compiling a periodic status report on their field. The UN Environment Programme (UNEP) issued the first in a proposed biennial series in 1998, titled Global Environment Outlook-1 or GEO-1. The second in the series, Global Environment Outlook 2000, was published in 1999. GEO-2000 is described by the UNEP's Executive Director, Klaus Töpfer, in the foreword as "a comprehensive integrated assessment of the global environment at the turn of the millennium, [and] a forward-looking document, providing a vision into the 21st century." Its status, however, is rendered uncertain by the printed caution that "The contents of this volume do not necessarily reflect the views or policies of UNEP or contributory organizations." GEO-2000 paints a generally bleak picture of environmental trends. It evidences a wide array of particulars ("In the Southern Ocean, the Patagonian toothfish is being over-fished and there is a large accidental mortality of seabirds caught up in fishing equipment"), but perhaps of more import are its statements about the root causes of environmental problems and what must be done. The excerpts below reflect some of these general views as they pertain to population. They are taken from the section entitled "Areas of danger and opportunity" in Chapter 1 of the report, and from the section "Tackling root causes" in Chapter 5. High resource consumption, fueled by affluent, Western lifestyles, is seen as a basic cause of environmental degradation. Cutting back this consumption will be required, freeing up resources for development elsewhere. Materialist values associated with urban living are part of the problem, given the concentration of future population growth in cities. And "genuine globalization" will entail free movement of people as well as capital and goods, thus optimizing "the population to environmental carrying capacity." Some of these positions are at least questionable: the supposed "innate environmental sensitivity of people raised on the land or close to nature," or the aim of "globalization of population movements." The latter does not appear in the recommendations, perhaps because of an implicit assumption that the effect of open borders on environmental trends is unlikely to be favorable. (For an earlier statement of the same sentiment,from 1927,see the comments by Albert Thomas, first director of the ILO, reproduced in the Archives section of PDR 9, no. 4.) [source] | ||||||||||||||||