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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

Biologie a stanovištní nároky ohroženého druhu stepníka Eresus moravicus (Araneae: Eresidae)v Česku / Biology and habitat requirements of endangered ladybird spider Eresus moravicus (Araneae: Eresidae) in Czechia

KREJČÍ, Tomáš January 2012 (has links)
The ladybird spider Eresus moravicus is one of our most endangered spiders. It is therefore necessary to know its habitat requirements and have at least basic knowledge of its biology to design an appropriate management to protect sites of its natural occurrence. Phytocenological analysis was made at each site and the outcomes were evaluated based on the Ellenberg´s indicator values. Also slope and exposure, litter layer and the quantity of rubbel were measured on the localities. Individuals were taken from burrows for the measurement of the prosoma length (investigation of the length of the life cycle). Exuviae were collected from the same burrows for measurement of the prosoma length. From these data the number of instars was determined. Prey remains were taken at most of those sites from 5?10 burrows and determined. Offsprings from several maternal burrows were taken, counted and weighted (research of fecundity of females). Weight of offsprings is important also in terms of their dispersion ability. The offsprings ability to balloon was investigated experimentally in laboratory conditions. The ladybird spider Eresus moravicus occurs in warm regions with high intensity of irradiation, mostly on the southern and southwestern slopes. Sites are characterized by poor herbaceous vegetation without trees and shrubs and by a thin layer of humus. Female lives for four years and the male for three years. The number of instars can reach to 13. Beetles (Coleoptera) are the most importent prey, the importent component of food are ants (Formicidae), too. Eresus moravicus has more offsprings than Eresus sandaliatus and Eresus kollari, more eggs in the cocoon than E. kollari and heavier offsprings than E. kollari and E. sandaliatus. In offsprings of E. moravicus and E. kollari pre-ballooning behavior of two types was observed: "tip-toe" behavior and "drop and swing" behavior.
2

Social Life Cycle Assessment in the Textile Industry: a case study in a small company

Grönkvist, Sofia January 2019 (has links)
Investigations of the textile industry and apparel sector often reveal unethical behaviours towards workers and lack of transparency in the value chain.  As consumers are getting more conscious and the external pressure and demand for more sustainable clothing increases, companies need to implement management systems to control their operations and ensure actions are socially responsible. The Social Life Cycle Assessment (S-LCA) methodology published by the United Nations Environment Programme in 2009 are suggested to measure positive and negative social impacts on stakeholders along a products entire life cycle, from cradle to grave. The methodology is still under development and no methods have yet been standardized or internationally recognized.   To contribute to the development of the S-LCA and its practical use in real world situations, the present study aims to evaluate the applicability of existing methodologies and tools by applying them to a cotton shirt from a small company in Sweden. The case study was performed by conducting an S-LCA following the four phases: Goal and scope; Life Cycle Inventory; Life Cycle Impact Assessment and; Life Cycle Interpretation. Generic country-level data and organisation specific data were collected through questionnaires, document review and desktop screening, while two different assessment tools were tested for the different data types. For generic country-level data, a Social Hotspot Assessment framework developed for this study, was applied and evaluated. For organisation specific data the existing Subcategory Assessment Method (SAM) was subject for feasibility evaluation.   The S-LCA conduction involved several application issues that affect the perceived applicability and feasibility of the methods. Problems identified relate to the definition of system boundaries and uncertainties in the choice of appropriate and relevant indicators. The major problems refer to data collection both in terms of availability and quality issues both with regards to the inventory and assessment phase. Further, in the assessment and interpretation phase uncertainties regarding assessment criteria’s and aggregation of results evolved when using the framework for identifying hotspots, affecting the reliability of the results.   Despite the identified issues, it is evident that it is possible to conduct and finalise a Social Hotspot Assessment using the methodology. However, based on the reliability issues of the results and the effort it requires, it is concluded that the applied framework is not feasible for smaller clothing companies with limited resources. The assessment of organisation specific data by applying SAM, is considered incomplete and identified issues reflect the incompatibility of the method and are thus not considered applicable or feasible for smaller companies.
3

Etude pétrologique et chronométrique (U-Th-Pb) de la monazite et du zircon dans les granulites de ultra-haute température du Rogaland, Norvège / Petrochronology of monazite and zircon in ultra-high temperature granulite from Rogaland, Norway

Laurent, Antonin 08 November 2016 (has links)
La compréhension des processus orogéniques nécessite un couplage toujours plus étroit entre données pétrologiques visant à contraindre le trajet pression-température des roches et les données géochronologiques donnant accès aux âges et durées absolues. Cette thèse vise en premier lieu à étudier le comportement des monazites et des zircons, utilisés en géochronométrie U-Th-Pb dans les granulites de ultra-haute température (UHT) du Rogaland (sud de la Norvège). Nous montrons que la datation ponctuelle in-situ U-Th-Pb, combinée à l'analyse des éléments majeurs et traces contenus dans la monazite permet d'identifier et de quantifier deux incursions à ultra-haute température du Rogaland à 1030-1005 Ma et à 940-930 Ma. En effet, l'examen des relations de phases à l'équilibre entre monazite, xénotime et huttonite a permis de démontrer que les monazites étaient capables de cristalliser et d'enregistrer des températures supérieures à 880 °C. D'autre part, la caractérisation chimique et isotopique U-Th-Pb-O des néocristallisations et surcroissances des zircons permet de définir un intervalle de temps de 60 Ma entre les deux pics de métamorphisme, au cours duquel la croûte moyenne était partiellement fondue à des températures supérieures à 800°C et à basse pression (0.7-0.4 GPa). Ces travaux de thèse soulignent par ailleurs la variété des facteurs susceptibles de conduire à la remise à zéro, partielle ou non, des âges U-Th-Pb dans les monazites et les zircons. Nous montrons que compte tenu de l'histoire T-t du domaine étudié, le système chronométrique U-Th-Pb est largement contrôlé dans le zircon par le degré d'amorphisation de ce dernier lié à son auto-irradiation, alors que dans la monazite, ce sont les processus de dissolution-recristallisation en présence de fluides silicatés ou aqueux qui sont prépondérants. Nous montrons également qualitativement l'influence des conditions d'oxydo-réduction dans l'incorporation du S comme sulfate dans le réseau cristallin de la monazite et par conséquent le potentiel que représente la monazite pour sonder l'état d'oxydo-réduction lié aux différents évènements géologiques, dans les roches métamorphiques. Finalement, nous mettons en évidence une corrélation spatiale et temporelle entre magmatisme mantellique et métamorphisme de ultra-haute température qui ne peut être expliquée avec les modèles actuellement acceptés pour la genèse du métamorphisme de UHT. Ces observations peuvent néanmoins être expliquées en prenant en compte la différence de composition et de température du manteau Protérozoïque comparé à l'actuel, favorisant le développement d'orogènes ultra-chauds et de phénomènes gravitaires. / Understanding mountain building processes requires a better integration of petrological and peochronological data in order to link pressure-temperature paths to absolute ages. This work focuses on the behaviour of monazite and zircon, which are used as geochronometers, in ultra-high temperature granulites of Rogaland (South Norway). We show that linking in-situ U-Th-Pb dating of monazite with its major- and trace-element composition lead to the recognition of two ultra-high temperature (UHT) metamorphic events in Rogaland at c.1030-1005 Ma and c. 940-930 Ma. Indeed, the examination of monazite-xenotime-huttonite phase relationships suggests that monazite may record crystallization age at or near ultra-high temperature. Besides, the chemical and U-Th-Pb-O isotopic characterization of zircon neo-crystallization or overgrowths indicates that the Rogaland crust remains molten (> 800 °C at 0.7-0.4 GPa) at least during 60 My between the two identified UHT excursions. This manuscript also highlights the various factors responsible for U-Th-Pb (partial) resetting in the course of granulite facies metamorphism. Zircon behaviour is mostly controlled its level of amorphization, enhancing Pb loss during annealing, whereas monazite resetting is dominated by dissolution-precipitation processes in the presence of a melt or fluid phase. More specifically, we point out that monazite may be used to monitor the redox conditions of its crystallizing medium since monazite may incorporate the redox-sensitive element S in its lattice as sulphate. Finally, we demonstrate a spatial and temporal correlation between magmatism and UHT metamorphism in Rogaland. The timescale, P-T path and tectono-magmatic history however cannot be explained by currently accepted models for UHT. We suggest that physical and thermal specificities of Proterozoic mantle may explain the observed ultra-hot orogen style and the occurrence of gravity driven processes during orogeny.
4

MOLECULAR DISTINCTIONS REGULATING THE TEMPORAL EXPRESSION OF THE MYOD-RESPONSIVE GENES PUMA (RESPONSIBLE FOR APOPTOSIS) AND MYOGENIN (RESPONSIBLE FOR DIFFERENTIATION)

Barrett, Brianna L. 08 May 2019 (has links)
No description available.
5

Assessment of media and communication from a sustainability perspective

Moberg, Åsa January 2010 (has links)
This thesis aims to assess potential environmental impacts of media and communication and to contribute to the development of methods for sustainability assessment. Although the main focus is on printed and electronic media products and environmental impacts, a broader sector analysis is also included and social aspects are discussed. The thesis provides a review of different environmental assessment tools in order to better understand their relationships and the appropriateness of different tools in different situations. Life cycle assessment (LCA) is used to assess printed and electronic versions of newspapers, books and invoices. Results of the screening LCAs of newspapers and books indicate that when comparing printed and electronic versions there are benefits and drawbacks for both. For news and books read on e-reading devices with energy efficient e-ink screens, the main environmental impacts in the studies stemmed from the production of the device and partly from disposal, with the latter having the potential to reduce some environmental impacts through recycling of materials. However, there are data gaps regarding the production of the e-reading devices, most notably for the e-ink screen and the waste management of obsolete e-reading devices. Existing data on internet energy use are uncertain. The potential impacts from a hypothetical total change from paper invoices to electronic invoices in Sweden were assessed through a screening consequential LCA regarding greenhouse gas emissions and cumulative energy demand. The results indicate that emissions and energy demand could decrease as a result of a change. The screening LCAs performed indicate that users’ practices could substantially influence the environmental impacts. Key factors which can influence results and comparisons of printed and electronic media products are total use of electronic devices, total use of printed media, amount and type of paper, energy use of electronic devices, potential printing of electronic media, electricity mix, and the system boundaries set for the assessments. To get a wider perspective, a sector study of the ICT sector and media sector concerning global greenhouse gas emissions and operational electricity use was performed. It was estimated that the contribution to global greenhouse gas emissions in 2007 was roughly 1-2 % for each sector. To assess media and communication products from a sustainability perspective, social aspects should also be covered. The author participated in an international project group on social aspects and LCA, one outcome from which was guidelines for social LCA (S-LCA). In addition to providing guidance for S-LCA, another important role of the guidelines is to facilitate discussions, criticism and proposals for improvement and development of the methodology being developed. The LCA and sector studies in this thesis are limited to direct and to some extent indirect environmental impacts. Further studies of the environmental impacts of more long-term changes in practices and potential structural changes, as well as potential social impacts, could provide important additional insights. This could increase the possibility of facilitating sustainable practices related to ICT and media. / QC 20100610

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