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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Towards Robust, Authoritative Assessments of Environmental Impacts Embodied in Trade: Current State and Recommendations

Tukker, Arnold, de Koning, Arjan, Owen, Anne, Lutter, Franz Stephan, Bruckner, Martin, Giljum, Stefan, Stadler, Konstantin, Wood, Richard, Hoekstra, Rutger January 2018 (has links) (PDF)
Global multiregional input-output databases (GMRIOs) became the standard tool for track ing environmental impacts through global supply chains. To date, several GMRIOs are available, but the numerical results differ. This paper considers how GMRIOs can be made more robust and authoritative. We show that GMRIOs need detail in environmentally relevant sectors. On the basis of a review of earlier work, we conclude that the highest uncertainty in footprint analyses is caused by the environmental data used in a GMRIO, followed by the size of country measured in gross domestic product (GDP) as fraction of the global total, the structure of the national table, and only at the end the structure of trade. We suggest the following to enhance robustness of results. In the short term, we recommend using the Single country National Accounts Consistent footprint approach, that uses official data for extensions and the national table for the country in question, combined with embodiments in imports calculated using a GMRIO. In a time period of 2 to 3 years, we propose work on harmonized environmental data for water, carbon, materials, and land, and use the aggregated Organization for Economic Cooperation and Development (OECD) Inter-Country Input-Output GMRIO as default in combination with detailing procedures developed in, for example, the EXIOBASE and Eora projects. In the long term, solutions should be coordinated by the international organizations such as the United Nations (UN) Statistical Division, OECD, and Eurostat. This could ensure that when input-output tables and trade data of individual countries are combined, that the global totals are consistent and that bilateral trade asymmetries are resolved.
2

Recent Progress in Assessment of Resource Efficiency and Environmental Impacts Embodied in Trade: An Introduction to this Special Issue

Tukker, Arnold, Giljum, Stefan, Wood, Richard January 2018 (has links) (PDF)
This paper serves as an introduction to this special issue on the use of multiregional input- output modeling in assessments of natural resource use and resource use efficiency. Due to globalization, growth in trade has outpaced growth in global gross domestic product (GDP). As a consequence, impacts of consumption of a country increasingly take place abroad. Various methods have been developed to perform so-called footprint analyses. We argue that global multiregional input-output (GMRIO) analysis has the largest potential to provide a consistent accounting framework to calculate a variety of different footprint indicators. The state of the art in GMRIO has, however, various shortcomings, such as limited sector and regional detail and incomplete extensions. The work presented in this special issue addresses a number of such problems and how to possibly overcome them, focusing on the construction of a new GMRIO database (EXIOBASE V3). This database includes long time series in both current and constant prices, a high level of product and sector detail, a physical representation of the world economy, and allows analyzing which footprints out of the many possible indicators provide most information for policy making. Various options for empirical analyses are presented in this special issue. Finally, we analyze how GMRIOs can be further standardized and gradually moved from the scientific to the official statistical domain.
3

Apport de l'antibiofilmogramme et de la mesure de la capacité de formation du biofilm dans la prise en charge des infections ostéo-articulaires à staphylocoques / Clinical value of the antibiofilmograma and contribution of biofilm formation capacity for the management of bone and joint infections due to staphylococcus

Tasse, Jason 06 July 2017 (has links)
Dans le cadre d'infections ostéo-articulaire (IOA), l'utilisation de matériels étrangers peut, en cas de contamination, aboutir à la formation d'un biofilm associé à un risque plus important d'échec du traitement et de récidive. Les bactéries sous forme de biofilm sont en effet protégées de l'action du système immunitaire et ont une tolérance plus importante aux antibiotiques. A l'heure actuelle, l'activité des antibiotiques est déterminée par la CMI (Concentration Minimale Inhibitrice), mais cette valeur ne tient pas compte de la forme sessile des bactéries. C'est pourquoi, la société BioFilm Control a développé un nouveau test, l'Antibiofilmogramme®, permettant de déterminer la CMI biofilm (CMIb) reflétant la capacité préventive des antibiotiques sur l'installation des microorganismes en biofilm. L'objectif de ma thèse a été dans un premier temps de participer à la démonstration de la valeur clinique de ce nouveau test dans le cadre des IOA à Staphylococcus aureus. Nous avons pu mettre en place un recueil prospectif et réaliser les premiers essais in vitro. Nos résultats obtenus pour la cloxacillin ont pu par la suite être confirmés sur un modèle in vivo d'infection sur matériel. Dans un second temps, nous avons pu caractériser la capacité de formation de biofilm des souches cliniques en fonction des profils de résistance obtenus en Antibiofilmogramme®. Nous avons pu mettre en évidence des profils différents liés à la clonalité des souches. Enfin, nous avons pu mettre au point une nouvelle méthode de rinçage et de quantification des biofilms pour les modèles en microplaque via l'utilisation de vapeur. Cette approche simple améliore grandement la reproductibilité des résultats et préserve l'intégrité structurelle des biofilms / In the context of Bone and Joint Infections (BJIs), the orthopedic devices are preferential surface for microorganisms to adhere and form biofilm associated with high rates of failures and relapses. Within biofilm, bacteria are protected from the host immune response and are able to survive in the presence of high concentration of antibiotics. The standard Minimal Inhibitory Concentration (MIC) informs on the antibiotic susceptibility of planktonic bacteria, but is not suited for biofilm. The company BioFilm Control developed a new test named Antibiofilmogram® which measures early-stage biofilm growth in presence of antibiotics, and provides a biofilm Minimal Inhibitory Concentration (bMIC). The aim of my PhD research was first to take part in the demonstration of the clinical value of this new test for Staphylococcus aureus BJIs. We established a prospective collection of data and strains and realized the first in vitro assays. Our results for cloxacillin were confirmed in an in vivo model of catheter-associated infection. Second, we characterized the biofilm formation capacity of various clinical isolates based on the Antibiofilmogram® resistance profile. We showed that the biofilm formation capacity is correlated with clonal lineage. Finally, we were able to develop a new method of washing and quantifying biofilms for microplate system using steam. This simple approach preserves the biofilm integrity and lead to highly reproducible data
4

Globalized impacts International trade accounting in a hybrid LCI method

Arbault, Damien January 2009 (has links)
Life-Cycle Assessment (LCA) covers a set of tools and techniques that aim to estimate the environmental impacts generated by a product or service all along its life-cycle including: rawmaterial extraction, production steps, transportation, use phase and end-of-life scenarios.The Life-Cycle Inventory (LCI) is a key step in LCA. It focuses on quantifying all physicaland/or monetary flows involved in the life-cycle of the product/service considered. Theseflows are named as ‘elementary flows’ in ISO terms. After having dealt with the main issuesof the ‘Goal and Scope definition’ step, that is giving a clear definition of the ‘functional unit’to consider, setting clear boundaries between elements to count in and those to disregard,practitioners need a coherent framework to quantify elementary flows and estimate missingelements. Several methodologies have been developed, each of them with both clearadvantages but also distinct disadvantages, depending on the purpose of the study: processbasedmethods, Input-Output based methods (IO-based methods), and also hybrid methods.In 2004, Suh suggested a method known as IHA (Integrated Hybrid Analysis) that appears towipe out the strict boundary between process-based and IO-based methods, taking advantagesof both methods as complementarities. Previous hybrid models were found incompleteregarding end-of-life scenario, especially with open-loop recycling.However, Suh admits that there remain several drawbacks in the IHA model, such as thetreatment of international trade and flows of products and services. They are usuallyconsidered as a single, homogeneous commodity despite their huge variety. This is apersistent limitation, already known by process-based and IO-based LCA practitioners. In aglobalized economy, where most products are manufactured in one place and consumed onthe other side of the world, this serious limitation cannot hold any longer.In this thesis, a review of both process-based, IO-based and hybrid methods for LCI ispresented, in terms of principles, advantages and limitations. It is followed by an explanationand demonstration of the mathematics underpinning the IHA model. Then, a model isproposed that would enable the model to take international trade into account. This is enabledthanks to the inspiration provided by a multi-regional framework proposed for ecologicalfootprint calculation. A numerical example supports this suggestion.The outcomes of this improved model are thought to go beyond its initial aims: the multiregionalIHA model could act as a variable geometry model where strongly affected regionsare efficiently focused on, without disregarding the others. This could prove efficient inavoiding side-effects of policy-making. Also, it would enable the development of moreregion-specific environmental impact coefficients, thus putting less pressure on fragileecosystems. The IHA model is a robust model: it is simple to handle – provided a userfriendlyinterface exists – but with a complex and evolutionary engine. It is compatible withan iterative progress in data collection. User-friendly software development could proveefficient to spread LCA practice and increase information exchange among industries,database builders and researchers. Using a multi-region framework would help industriescustomize impact assessment according to both the regional environmental condition andspecific geographic distribution of the supply chain, thus enriching their toolbox for strategicplanning.
5

Iron and Oxygen Isotope Signatures of Magnetite in Iron Ore of Kiruna Type / Järn- och syre-isotoper hos magnetit i järnmalm av Kirunatyp

Andersson, Malin January 2020 (has links)
Stable isotope analysis of iron and oxygen isotopes in magnetite of Kiruna-type from Sweden and Chile have been conducted to further the understanding of the formation, and advance the analysis methods of these deposits. For this, data from SIMS (secondary ion mass spectroscopy), EBSD (electron backscatter diffraction) and triple oxygen analysis (by laser fluorination) are used. Some researchers have found that crystal orientation can affect the oxygen and iron isotope ratios when analysing magnetite by SIMS, complicating the process. EBSD analysis therefore aided by finding the orientations of the crystals prior to SIMS analysis. Magnetite from Kiruna have been tested for use as SIMS reference material, but it did not prove to be suitable at present time. Further homoegeneity tests can be useful before declaring the sample as unsuitable. Preliminary iron isotope results from SIMS on magnetite from Kiirunavaara indicate an internal variation of δ 56 Fe between -0.72-0.70 per mil, with an uncertainty of 0.38 per mil (1σ). The variations could not be determined to match crystal orientations. Triple oxygen analyses show very low ∆'17 O on Kiruna samples, -357 to -171 ‰, indicating a strong MIF-O (mass-independently fractionated oxygen isotope composition) component. The MIF-O signal is also present in ∆'17 O records in evaporites from similar ages (1.7 - 1.9 Ga) (Crockford et al. 2019), which are known to partly contain oxygen derived from atmospheric O 2 . The MIF-O signal was not present in the Chilean magnetite samples, however, they are within the ∆'17 range of evaporites (Crockford et al.2019) from a similiar age (0 Ma vs 2 Ma). It is proposed that magmatic fluids interacted with evaporites, exchanging oxygen isotopes, before forming magnetite of Kiruna-type, thereby allowing the magnetite to contain part of the atmospheric isotopic record.
6

Utilizing a tectonic framework to constrain the mineral system and remobilization in the Kiruna mining district, Sweden

Logan, Leslie January 2022 (has links)
The Kiruna mining district, located in the northern Norrbotten ore province, Sweden, is a geologically and economically important area, being the type-locality for Kiruna iron oxide-apatite (IOA) deposits and also host to a variety of other deposits including syngenetic stratiform exhalative Cu-(Fe-Zn) (Viscaria, Eastern Pahtohavare), epigenetic stratabound Cu ± Au (Pahtohavare), and iron oxide-copper-gold (IOCG, Rakkurijärvi) deposits. However, the timing of IOA versus IOCG within the tectonic evolution is in question based on structural investigations showing Cu- and Fe-sulfides occur in late-orogenic structures. Here we use an established tectonic framework to constrain mineral systems (tectonic/thermal drives, metal and ligand sources, fluid pathways, traps, remobilization mechanisms) related to the early and late phases of the Svecokarelian orogeny in the Kiruna mining district. U-Pb zircon geochronology of intrusions in the district indicates a thermal drive was present during the early phase of the Svecokarelian orogeny from ca. 1920-1865 Ma, however remains enigmatic for the late Svecokarelian orogeny. Zircon grains from a magnetite-ilmenite gabbro yielded an age of 1881 ± 8 Ma, coeval with the Kiirunavaara IOA deposit and suggested to represent an important generation of mafic magmatism related to the ore. Lithogeochemistry of early bimodal Svecokarelian intrusions in the district indicates a within-plate to active continental margin environment with a volcanic arc affinity, pointing to a back arc environment. Epsilon Ndi and 87Sr/86Sri values calculated from the U-Pb ages for the igneous intrusions were compared to samples of ore-related alteration from epigenetic Pahtohavare and Rakkurijärvi deposits, district greenstone, and Archean samples. Results show that each deposit sourced Sr and Nd from a variety of rocks suggesting broad fluid transport. Each deposit has a distinct Sr mixing trend suggesting they formed from different ore-forming fluids and pathways. This is supported by new structural data that constrain the folding event and the ore-related quartz-carbonate-sulfide veins in the Pahtohavare area to a late orogenic timing, compared to the early orogenic timing of Rakkurijärvi. Sulfide trace element and sulfur isotope data from structurally constrained ores within the tectonic framework also record distinct characteristics between early and late deposits. However, remobilization of early Pahtohavare sulfides associated to an increase in Co content and heavier sulfur isotope compositions is recorded. The results of this study illustrate that using a structural framework approach to constrain the ingredients of mineral systems is a powerful strategy for interpreting ore deposit processes in tectonically complex terrains where both IOA and IOCG deposits occur.

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