961 resultados para Site-specific application


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A total of five sediment cores from three sites, the Arctic Ocean, the Fram Strait and the Greenland Sea, yielded evidence for geomagnetic reversal excursions and associated strong lows in relative palaeointensity during oxygen isotope stages 2 and 3. A general similarity of the obtained relative palaeointensity curves to reference data can be observed. However, in the very detail, results from this high-resolution study differ from published records in a way that the prominent Laschamp excursion is clearly characterized by a significant field recovery when reaching the steepest negative inclinations, whereas only the N-R and R-N transitions are associated with the lowest values. Two subsequent excursions also reach nearly reversed inclinations but without any field recovery at that state. A total of 41 accelerator mass spectrometry (AMS) 14C ages appeared to allow a better age determination of these three directional excursions and related relative palaeointensity variations. However, although the three sites yielded more or less consistent chronological as well as palaeomagnetic results a comparison to another site, PS2644 in the Iceland Sea, revealed significant divergences in the ages of the geomagnetic field excursions of up to 4 ka even on basis of uncalibrated AMS 14C ages. This shift to older 14C ages cannot be explained by a time-transgressive character of the excursions, because the distance between the sites is small when compared with the size of and the distance to the geodynamo in the Earth's outer core. The most likely explanation is a difference of reservoir ages and/or mixing with old 14C-depleted CO2 from glacier ice expelled from Greenland at site PS2644.

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Radiocarbon age relationships between co-occurring planktic foraminifera, alkenones, and total organic carbon in sediments from the continental margins of southern Chile, northwest Africa, and the South China Sea were compared with published results from the Namibian margin. Age relationships between the sediment components are site-specific and relatively constant over time. Similar to the Namibian slope, where alkenones have been reported to be 1000-4500 years older than co-occurring foraminifera, alkenones were significantly (~1000 years) older than co-occurring foraminifera in the Chilean margin sediments. In contrast, alkenones and foraminifera were of similar age (within 2 sigma error or better) in the NW African and South China Sea sediments. Total organic matter and alkenone ages were similar off Namibia (age difference TOC alkenones: 200-700 years), Chile (100-450 years), and NW Africa (360-770 years), suggesting minor contributions of preaged terrigenous material. In the South China Sea, total organic carbon is significantly (2000-3000 years) older owing to greater inputs of preaged terrigenous material. Age offsets between alkenones and planktic foraminifera are attributed to lateral advection of organic matter. Physical characteristics of the depositional setting, such as seafloor morphology, shelf width, and sediment composition, may control the age of co-occurring sediment components. In particular, offsets between alkenones and foraminifera appear to be greatest in deposition centers in morphologic depressions. Aging of organic matter is promoted by transport. Age offsets are correlated with organic richness, suggesting that formation of organic aggregates is a key process.

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In 2014 the United States Forest Service closed the Gold Basin Campground of western Washington in an effort to protect the public from unstable hillslopes directly adjacent to the campground. The Gold Basin Landslide Complex (GBLC) is actively eroding via block fall, dry ravel, and debris flows, which contribute sediment into the South Fork of the Stillaguamish River. This sediment diminishes the salmonid population within the South Fork of the Stillaguamish River by reducing habitable spawning grounds, which is a big concern to the Stillaguamish Tribe of Indians. In this investigation, I quantified patterns of degradation and total volume of sediment erosion from the middle lobe of the GBLC over the period of July 2015 through January 2016 using terrestrial (ground-based) LiDAR (TLS). I characterized site specific stratigraphy and geomorphic processes, and laid the groundwork for future, long-term monitoring of this site. Results of this investigation determined that ~ 4,800m3 of sediment was eroded from the middle lobe of the GBLC during the 6 month study period (July 2015 – January 2016). This erosion likely occurred from debris flows, raveling of poorly sorted sand and gravel deposits and block failures of high plasticity silts and clays, and/or other mass wasting mechanisms. The generalized stratigraphic sequence in the GBLC consists of alternating massive beds of sand and gravel with silts and clays. The low permeability of these silts and clays provide a perfect venue for groundwater to percolate, as I observed during field investigations, which likely contributes to the active instability of the hillslopes. Continued monitoring and mapping of this complex will lead to viable information that could help both the United States Forest Service and the Stillaguamish Tribe.

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Powder metallurgy alloys are typically inhomogeneous with a significant amount of porosity. This complicates conventional transmission electron microscopy sample preparation. However, the use of focused ion beam milling allows site specific transmission electron microscopy samples to be prepared in a short amount of time. This paper presents a method that can be used to produce transmission electron microscopy samples from an Al-Cu-Mg PM alloy. (C) 2003 IoM Communications Ltd. Published by Maney for the Institute of Materials, Minerals and Mining.

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Although smoking is widely recognized as a major cause of cancer, there is little information on how it contributes to the global and regional burden of cancers in combination with other risk factors that affect background cancer mortality patterns. We used data from the American Cancer Society's Cancer Prevention Study II (CPS-II) and the WHO and IARC cancer mortality databases to estimate deaths from 8 clusters of site-specific cancers caused by smoking, for 14 epidemiologic subregions of the world, by age and sex. We used lung cancer mortality as an indirect marker for accumulated smoking hazard. CPS-II hazards were adjusted for important covariates. In the year 2000, an estimated 1.42 (95% CI 1.27-1.57) million cancer deaths in the world, 21% of total global cancer deaths, were caused by smoking. Of these, 1.18 million deaths were among men and 0.24 million among women; 625,000 (95% CI 485,000-749,000) smoking-caused cancer deaths occurred in the developing world and 794,000 (95% CI 749,000-840,000) in industrialized regions. Lung cancer accounted for 60% of smoking-attributable cancer mortality, followed by cancers of the upper aerodigestive tract (20%). Based on available data, more than one in every 5 cancer deaths in the world in the year 2000 were caused by smoking, making it possibly the single largest preventable cause of cancer mortality. There was significant variability across regions in the role of smoking as a cause of the different site-specific cancers. This variability illustrates the importance of coupling research and surveillance of smoking with that for other risk factors for more effective cancer prevention. (C) 2005 Wiley-Liss, Inc.

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The basis of this work was to investigate the relative environmental impacts of various power generators knowing that all plants are located in totally different environments and that different receptors will experience different impacts. Based on IChemE sustainability metrics paradigm, we calculated potential environmental indicators (P-EI) that represent the environmental burden of masses of potential pollutants discharged into different receiving media. However, a P-EI may not be of significance, as it may not be expressed at all in different conditions, so to try and include some receiver significance we developed a methodology to take into account some specific environmental indicators (S-EI) that refer to the environmental attributes of a specific site. In this context, we acquired site specific environmental data related to the airsheds and water catchment areas in different locations for a limited number of environmental indicators such as human health (carcinogenic) effects, atmospheric acidification, photochemical (ozone) smog and eutrophication. The S-EI results from this particular analysis show that atmospheric acidification has highest impact value while health risks due to fly ash emissions are considered not to be as significant. This is due to the fact that many coal power plants in Australia are located in low population density air sheds. The contribution of coal power plants to photochemical (ozone) smog and eutrophication were not significant. In this study, we have considered emission related data trends to reflect technology performance (e.g., P-EI indicators) while a real sustainability metric can be associated only with the specific environmental conditions of the relevant sites (e.g., S-EI indicators).

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We work collectively with varied locative-type projects and look to integrate our students into contemporary experience design culture. Students experience the ‘how and what’ of locative by becoming participant users, being exposed to contemporary works, and placing themselves in the role of the designer producing their own located works.

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Load-induced extravascular fluid flow has been postulated to play a role in mechanotransduction of physiological loads at the cellular level. Furthermore, the displaced fluid serves as a carrier for metabolites, nutrients, mineral precursors and osteotropic agents important for cellular activity. We hypothesise that load-induced fluid flow enhances the transport of these key substances, thus helping to regulate cellular activity associated with processes of functional adaptation and remodelling. To test this hypothesis, molecular tracer methods developed previously by our group were applied in vivo to observe and quantify the effects of load-induced fluid flow under four-point-bending loads. Preterminal tracer transport studies were carried out on 24 skeletally mature Sprague Dawley rats. Mechanical loading enhanced the transport of both small- and larger-molecular-mass tracers within the bony tissue of the tibial mid-diaphysis. Mechanical loading showed a highly significant effect on the number of periosteocytic spaces exhibiting tracer within the cross section of each bone. For all loading rates studied, the concentration of Procion Red tracer was consistently higher in the tibia subjected to pure bending loads than in the unloaded, contralateral tibia, Furthermore, the enhancement of transport was highly site-specific. In bones subjected to pure bending loads, a greater number of periosteocytic spaces exhibited the presence of tracer in the tension band of the cross section than in the compression band; this may reflect the higher strains induced in the tension band compared with the compression band within the mid-diaphysis of the rat tibia. Regardless of loading mode, the mean difference between the loaded side and the unloaded contralateral control side decreased with increasing loading frequency. Whether this reflects the length of exposure to the tracer or specific frequency effects cannot be determined by this set of experiments. These in vivo experimental results corroborate those of previous ex vivo and in vitro studies, Strain-related differences in tracer distribution provide support for the hypothesis that load-induced fluid flow plays a regulatory role in processes associated with functional adaptation.

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Many variables that are of interest in social science research are nominal variables with two or more categories, such as employment status, occupation, political preference, or self-reported health status. With longitudinal survey data it is possible to analyse the transitions of individuals between different employment states or occupations (for example). In the statistical literature, models for analysing categorical dependent variables with repeated observations belong to the family of models known as generalized linear mixed models (GLMMs). The specific GLMM for a dependent variable with three or more categories is the multinomial logit random effects model. For these models, the marginal distribution of the response does not have a closed form solution and hence numerical integration must be used to obtain maximum likelihood estimates for the model parameters. Techniques for implementing the numerical integration are available but are computationally intensive requiring a large amount of computer processing time that increases with the number of clusters (or individuals) in the data and are not always readily accessible to the practitioner in standard software. For the purposes of analysing categorical response data from a longitudinal social survey, there is clearly a need to evaluate the existing procedures for estimating multinomial logit random effects model in terms of accuracy, efficiency and computing time. The computational time will have significant implications as to the preferred approach by researchers. In this paper we evaluate statistical software procedures that utilise adaptive Gaussian quadrature and MCMC methods, with specific application to modeling employment status of women using a GLMM, over three waves of the HILDA survey.

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Introduction – Why do we need ‘biomarkers? Biomarkers of protein oxidation Introduction Major issues/questions Protein carbonyl biomarkers Biochemistry Methods of measurement Storage, stability and limitations in use Protein thiol biomarkers Biochemistry Methods of measurement Storage, stability and limitations on use Aliphatic amino acid biomarkers Biochemistry Methods of measurement Storage, stability and limitations on use Oxidised Tryptophan Biomarkers Biochemistry Method of measurement Storage, stability and limitations on use Oxidised tyrosine biomarkers Biochemistry Methods of measurement Storage, stability and limitations on use Formation of neoepitopes on oxidised proteins Validation of assays for protein oxidation biomarkers Relationship of protein oxidation to disease Modulation of protein oxidation biomarkers by antioxidants Future perspectives Introduction to lipid peroxidation biomarkers Introduction: biochemistry of lipid peroxidation Malondialdehyde Methods of measurement Storage, stability and limitations on use Conjugated dienes Method of measurement Storage, stability and limitations of use LDL lag phase Method of measurement Storage, stability and limitations of use Hydrocarbon gases Biochemistry Method of measurement Storage, stability and limitations on use Lipofuscin Biochemistry Method of measurement Storage, stability and limitation on use Lipid peroxides Biochemistry Method of measurement Storage, stability and limitations on use Isoprostanes Biochemistry Method of measurement Storage, stability and limitations on use Possible new biomarkers of lipid oxidation Relationship of lipid peroxidation to disease Modulation of lipid peroxidation biomarkers by antioxidants Functional consequences of lipid peroxidation Contribution of dietary intake to lipid peroxidation products Biomarkers of DNA oxidation Introduction Confounding factors Units and terminology Nuclear and mitochondrial DNA damage Lymphocytes as surrogate tissues Measurement of DNA damage with the comet assay Practical details Storage, stability, and limitations of the assay Measurement of DNA base oxidation by HPLC Practical details Storage, stability and limitations of the method Measurement of DNA base oxidation by GC–MS Biochemistry of 8-oxoguanine, adenine and fapy derivatives Methods of measurement Storage, stability and limitations of the method Analysis of guanine oxidation products in urine Method of measurement Limitations and criticisms Immunochemical methods Methods of measurement Storage, stability, and limitations of the assay 32P post-labelling Method of measurement Limitations and criticisms Validation of assays for DNA oxidation Oxo-dGuo in lymphocyte DNA Urinary measurements DNA–aldehyde adducts Biochemistry Method of measurement Products of reactive nitrogen species Endpoints arising from oxidative DNA damage Mutations Chromosome aberrations Micronuclei Site-specific DNA damage Relationship of DNA oxidation to disease Modulation of DNA oxidation biomarkers by antioxidants Direct and indirect effects of oxidative stress: measures of total oxidant/antioxidant levels Visualisation of cellular oxidants Biochemistry: histochemical detection of ROS Method of measurement Limitations, storage and stability Measurement of hydrogen peroxide Biochemistry Methods of measurement Storage, stability and limitations on use Measurement of the ratio of antioxidant/oxidised antioxidant Biochemistry Method of measurement Storage, stability and limitations on use Total antioxidant capacity Biochemistry Terminology Methods of measurement Storage, stability and limitations on use Validation of assays for direct oxidant and antioxidant biomarkers Relationship of oxidant/antioxidant measurement to disease Modulation of oxidant/antioxidant biomarkers by dietary antioxidants Induction of genes in response to oxidative stress Background Measurement of antioxidant responsive genes and proteins Effects of antioxidant intake on the activity of antioxidant enzymes

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In many Environmental Information Systems the actual observations arise from a discrete monitoring network which might be rather heterogeneous in both location and types of measurements made. In this paper we describe the architecture and infrastructure for a system, developed as part of the EU FP6 funded INTAMAP project, to provide a service oriented solution that allows the construction of an interoperable, automatic, interpolation system. This system will be based on the Open Geospatial Consortium’s Web Feature Service (WFS) standard. The essence of our approach is to extend the GML3.1 observation feature to include information about the sensor using SensorML, and to further extend this to incorporate observation error characteristics. Our extended WFS will accept observations, and will store them in a database. The observations will be passed to our R-based interpolation server, which will use a range of methods, including a novel sparse, sequential kriging method (only briefly described here) to produce an internal representation of the interpolated field resulting from the observations currently uploaded to the system. The extended WFS will then accept queries, such as ‘What is the probability distribution of the desired variable at a given point’, ‘What is the mean value over a given region’, or ‘What is the probability of exceeding a certain threshold at a given location’. To support information-rich transfer of complex and uncertain predictions we are developing schema to represent probabilistic results in a GML3.1 (object-property) style. The system will also offer more easily accessible Web Map Service and Web Coverage Service interfaces to allow users to access the system at the level of complexity they require for their specific application. Such a system will offer a very valuable contribution to the next generation of Environmental Information Systems in the context of real time mapping for monitoring and security, particularly for systems that employ a service oriented architecture.

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Original Paper European Journal of Information Systems (2001) 10, 135–146; doi:10.1057/palgrave.ejis.3000394 Organisational learning—a critical systems thinking discipline P Panagiotidis1,3 and J S Edwards2,4 1Deloitte and Touche, Athens, Greece 2Aston Business School, Aston University, Aston Triangle, Birmingham, B4 7ET, UK Correspondence: Dr J S Edwards, Aston Business School, Aston University, Aston Triangle, Birmingham, B4 7ET, UK. E-mail: j.s.edwards@aston.ac.uk 3Petros Panagiotidis is Manager responsible for the Process and Systems Integrity Services of Deloitte and Touche in Athens, Greece. He has a BSc in Business Administration and an MSc in Management Information Systems from Western International University, Phoenix, Arizona, USA; an MSc in Business Systems Analysis and Design from City University, London, UK; and a PhD degree from Aston University, Birmingham, UK. His doctorate was in Business Systems Analysis and Design. His principal interests now are in the ERP/DSS field, where he serves as project leader and project risk managment leader in the implementation of SAP and JD Edwards/Cognos in various major clients in the telecommunications and manufacturing sectors. In addition, he is responsible for the development and application of knowledge management systems and activity-based costing systems. 4John S Edwards is Senior Lecturer in Operational Research and Systems at Aston Business School, Birmingham, UK. He holds MA and PhD degrees (in mathematics and operational research respectively) from Cambridge University. His principal research interests are in knowledge management and decision support, especially methods and processes for system development. He has written more than 30 research papers on these topics, and two books, Building Knowledge-based Systems and Decision Making with Computers, both published by Pitman. Current research work includes the effect of scale of operations on knowledge management, interfacing expert systems with simulation models, process modelling in law and legal services, and a study of the use of artifical intelligence techniques in management accounting. Top of pageAbstract This paper deals with the application of critical systems thinking in the domain of organisational learning and knowledge management. Its viewpoint is that deep organisational learning only takes place when the business systems' stakeholders reflect on their actions and thus inquire about their purpose(s) in relation to the business system and the other stakeholders they perceive to exist. This is done by reflecting both on the sources of motivation and/or deception that are contained in their purpose, and also on the sources of collective motivation and/or deception that are contained in the business system's purpose. The development of an organisational information system that captures, manages and institutionalises meaningful information—a knowledge management system—cannot be separated from organisational learning practices, since it should be the result of these very practices. Although Senge's five disciplines provide a useful starting-point in looking at organisational learning, we argue for a critical systems approach, instead of an uncritical Systems Dynamics one that concentrates only on the organisational learning practices. We proceed to outline a methodology called Business Systems Purpose Analysis (BSPA) that offers a participatory structure for team and organisational learning, upon which the stakeholders can take legitimate action that is based on the force of the better argument. In addition, the organisational learning process in BSPA leads to the development of an intrinsically motivated information organisational system that allows for the institutionalisation of the learning process itself in the form of an organisational knowledge management system. This could be a specific application, or something as wide-ranging as an Enterprise Resource Planning (ERP) implementation. Examples of the use of BSPA in two ERP implementations are presented.

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The chromosomal ß-lactamase of Pseudomonas aeruginosa SAlconst (a derepressed laboratory strain) was isolated and purified. Two peaks of activity were observed on gel permeation chromatography (one major peak mol. wt. 45 kD and one minor peak of 54 kD). Preparations from 12 clinical derepressed strains showed identical results. Chromosomal ß-lactamase production in both normal and derepressed P. aeruginosa strains was induced both by iron restricted growth conditions and by penicillin G. The majority of the enzyme (80-90%) was found in the periplasm and cytoplasm but a significant amount (2-20%) was associated with the outer membrane (OM). The growth conditions did not affect the distribution of the enzyme between subcellular fractions although higher activity was found in the cells grown under iron limitation and/ or in the presence of ß-lactams. The penicillanate sulphone inhibitor, tazobactam, displayed irreversible kinetics whilst cloxacillin, cefotaxime, ampicillin and penicillin G were all competitive inhibitors of the enzyme. Similar results were obtained for the Enterobacter cloacae P99 [ß-lactamase, but tazobactam displayed a non-classical kinetic pattern for the Staphylococcus aureus PC1 ß-lactamase. The residues involved in ß-lactam hydrolysis by the P aeruginosa SAlconst enzyme were detennined by affinity labelling with tazobactam. A tryptic digestion fragment of the inhibited enzyme contained the amino acids D, T, S, E, P, G, A, C, V, M, I, Y, F, H, K, R. This suggests the involvement of the conserved SVSK, DAE and KTG motifs found in all penicillin sensitive proteins. A model of the 3-D structure of the active site of the P aeruginosa SAlconst chromosomal ß-!actamase was constructed from the published amino acid sequence of P aeruginosa chromosomal ß-lactamase and the a-carbon coordinates of the S. aureus PCI ß-lactamase by homology modelling and energy minimisation. The crystal structure of tazobactam was determined and energy minimised. Computer graphics docking identified Ser 72 as a possible residue involved in a secondary attack on the C5 position of tazobactam after initial ß-lactam hydrolysis by serine 70. The enhanced activity of tazobactam over sulbactam might be explained by the triazole substituent which might participate in favourable hydrogen bonding between N3 and active site residues.

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Risk and knowledge are two concepts and components of business management which have so far been studied almost independently. This is especially true where risk management is conceived mainly in financial terms, as, for example, in the banking sector. The banking sector has sophisticated methodologies for managing risk, such as mathematical risk modeling. However. the methodologies for analyzing risk do not explicitly include knowledge management for risk knowledge creation and risk knowledge transfer. Banks are affected by internal and external changes with the consequent accommodation to new business models new regulations and the competition of big players around the world. Thus, banks have different levels of risk appetite and policies in risk management. This paper takes into consideration that business models are changing and that management is looking across the organization to identify the influence of strategic planning, information systems theory, risk management and knowledge management. These disciplines can handle the risks affecting banking that arise from different areas, but only if they work together. This creates a need to view them in an integrated way. This article sees enterprise risk management as a specific application of knowledge in order to control deviation from strategic objectives, shareholders' values and stakeholders' relationships. Before and after a modeling process it necessary to find insights into how the application of knowledge management processes can improve the understanding of risk and the implementation of enterprise risk management. The article presents a propose methodology to contribute to providing a guide for developing risk modeling knowledge and a reduction of knowledge silos, in order to improve the quality and quantity of solutions related to risk inquiries across the organization.