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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.
301

The role of ethical business behaviour awareness in consumer sports supplement purchase intentions

Gottsche, Louise Theresia 27 July 2011 (has links)
The gap between ethical purchase intentions and ethical purchase behaviour is well-documented. Although this gap can be bridged by increasing the level of awareness among consumers with regards to ethical business practices, it was found that consumers between the ages of 19 to 56 years were already aware of ethical organisations and business practices in the South African sports supplement industry. They are however unaware of companies that operate unethically. Several factors such as brand familiarity, price and convenience were found to compete with ethical business behaviour during the purchase decision-making process. It is thus recommended that organisations that incorporate ethical business behaviour at a strategic level should provide ethical products that are competitively priced, convenient to use and from a brand that is familiar / Graduate School of Business Leadership / MBA
302

"Det är vårt eget samhälle som gör det svårt att jobba med den här gruppen" : En kvalitativ intervjustudie om socialarbetares upplevelser av att arbeta med romska EU-medborgare / ”It’s our own society that makes it hard to work with this group” : A qualitative interview study on social workers experiences of working with Roma EU-citizens

Lenerhard, Evelina January 2015 (has links)
Romani people came to Sweden in the early 16th century and is today acknowledged as a minority group. Today in Sweden there’s a large group of Roma EU-citizens who come to beg. Romani people has been an exposed and discriminated group since their arrival in Sweden – a pattern that’s still relevant regarding Roma EU-citizens coming today. One profession that faces Roma EU-citizens in their work is social workers. This study aims to describe and analyse how social workers experience working with Roma EU-citizens, what difficulties or opportunities they see and how this work can be developed in the future. Furthermore, the study examines what beliefs social workers feel exists in society surrounding this group. The study uses labelling theory and theories of cultural competence. Six interviews were conducted with social workers and the study uses a qualitative approach and a hermeneutic perspective. Study results indicate that cultural differences affects working with the group. Results also show that the social workers feel there’s a lot of prejudice against the group. The study concludes that cultural competence is important in order to perform a good social work with the Romani group. Another conclusion is that structural problems complicates working with the group.
303

Enhancing nucleic acid detection using inductively coupled plasma mass spectrometry, by means of metal and nano-particle labelling

Kerr, Samantha Louise January 2008 (has links)
The application of ICP-MS to the fields of proteomics and genomics has arisen in part due to its ability to detect and quantify trace levels of S and P, which are major constituents in proteins and nucleic acids respectively. The development of collision/reaction cell technology and high resolution instruments has enabled these biologically important elements to be measured and quantified at the pg - ng ml-1 level. Despite these advances, the detection limits of P and S are still inferior compared to other elements. Oligonucleotides containing biotin functionality were labelled with Au nano-particles attached to a streptavidin protein to achieve site specific labelling, with 100% labelling efficiency. Each nano-particle contained ~86 Au atoms, resulting in an 882 fold signal enhancement for 24 base length oligonucleotides. However, this enhancement factor was only observed when one oligonucleotide bound to one nano-particle in a 1:1 ratio. Much lower Au labelling efficiencies and signal enhancements were observed when thiolated oligonucleotides were labelled with maleimide functionalised gold nano-particles. This was attributed to the extensive and difficult sample preparation steps that were required prior to labelling. The detection and quantification of adducts formed between DNA and the Pt anti-cancer drugs cisplatin and oxaliplatin were also investigated with ICP-MS. Acid digestion of the carbon based DNA matrix enabled Pt adducts to be quantified at low dose rates of 1 Pt atom per 1 500 000 nucleotides in ~12 μg DNA. Such sensitive mass spectrometric determinations could be employed in clinical tests to detect and quantify low level adducts formed in patients in-vivo. To complement ICP-MS analysis, electrospray ionisation linear ion trap mass spectrometry was employed to study the interaction of oxaliplatin with the four DNA nucleobases. Multiple stage mass spectrometry enabled detailed Pt-nucleobase adduct fragmentation pathways to be established. The method of DNA detection using P in conjunction with the collision cell, or cool plasma to form PO+ was also demonstrated and the limitations of the method, namely, polyatomic interferences and severe matrix effects were highlighted.
304

The role of ethical business behaviour awareness in consumer sports supplement purchase intentions

Gottsche, Louise Theresia 27 July 2011 (has links)
The gap between ethical purchase intentions and ethical purchase behaviour is well-documented. Although this gap can be bridged by increasing the level of awareness among consumers with regards to ethical business practices, it was found that consumers between the ages of 19 to 56 years were already aware of ethical organisations and business practices in the South African sports supplement industry. They are however unaware of companies that operate unethically. Several factors such as brand familiarity, price and convenience were found to compete with ethical business behaviour during the purchase decision-making process. It is thus recommended that organisations that incorporate ethical business behaviour at a strategic level should provide ethical products that are competitively priced, convenient to use and from a brand that is familiar / Graduate School of Business Leadership / MBA
305

Constructing and contesting the legitimacy of private forest governance : The case of forest certification in Sweden

Johansson, Johanna January 2013 (has links)
In recent decades, political scientists have devoted substantial attention to the changing role of the state towards more inclusion of non-state actors in policymaking. This deliberative turn, or move towards governance, may signal inability to handle complex problems without cooperation with nonstate actors. On the other hand, governance is frequently credited with generating legitimate decision-making processes and results. In some instances, non-governmental actors have even taken the lead in policymaking. One archetype of such private governance, which has received significant scholarly attention, is forest certification. The Forest Stewardship Council (FSC) is frequently described as the most democratic and therefore legitimate forest certification organization since it grants equal voting rights to three stakeholder groups in the formulation of criteria for responsible forestry: environmental non-governmental organizations (ENGOs), social groups (indigenous peoples and labor organizations) and forest owners. However, in Sweden, a country often described as a role model in forest certification, the FSC has increasingly received critique for failing to generate legitimate processes and results, and recently three of five ENGOs have chosen to exit the FSC organization. Such processes of de-legitimation have received little attention in the forest certification literature. This thesis therefore provides a critical assessment of the legitimacy of forest certification in Sweden. Legitimacy is analyzed through concerned stakeholders’ perceptions of both procedural qualities (input legitimacy) and problem-solving capacity (output legitimacy). This study of legitimacy is combined with an assessment of the ability of certification to enhance environmental protection, defined as changes in both forest management practices and biophysical conditions. The thesis focuses not the least on legitimacy on the local level, which is where the actual implementation takes place. Today local studies of the legitimacy of forest certification are rare. Both quantitative and qualitative research methods are applied and a number of sources are analyzed: forest monitoring data, survey data, interviews with and documents produced by the participating stakeholders. Papers I and IV analyze the perceived legitimacy of forest certification, while Papers II and III analyze forest certification schemes’ ability to enhance environmental protection. The results show that a process of de-legitimation is occurring in Swedish forest certification. In particular, certification has lost legitimacy with ENGOs, which increasingly consider Swedish forest certification to lack both input legitimacy and output legitimacy. Moreover, although the Swedish FSC standard pays attention to reindeer husbandry, the results show that reindeer herders consider themselves to have limited power to influence long-term forest planning and management (low output legitimacy). The forest industry, on the other hand, increasingly grants legitimacy to forest certification due to customer demands, which are created not the least by pressures from international ENGOs and by EU regulation. The results also show that Swedish forest companies have paid more attention to their environmental practices after obtaining certification. However, to what extent these changes result in positive environmental impacts remains uncertain, especially since forests in Sweden grow slowly, which requires analyses over time. There are also measurement problems resulting from the low certification rate among small-scale forest owners and from the fact that certified small-scale owners tend to be more active in their management. These findings highlight that research on private forest governance should not neglect the role of the state, neither as a buyer nor as a regulator. These findings also suggest that further research should pay attention to power asymmetries in private governance and develop methods for better understanding and evaluating the certification schemes’ environmental and social impacts.
306

Investigation of the neural correlates of ongoing pain states using quantitative perfusion arterial spin labelling

Segerdahl, Andrew Reilly January 2011 (has links)
At present, there are few clinically effective pain therapies available to treat chronic pain. One reason is due to a lack of understanding about how pain emerges in the brain. Excitingly, an emerging body of work suggests that the perfusion imaging technique, arterial spin labelling (ASL), is particularly well-suited to investigate this issue. The primary aim of this thesis is to develop and optimise a quantitative perfusion imaging approach to investigate the neural correlates of both experimental and pathological tonic pain. In Chapter 2, we explore different methods of inducing ongoing pain in healthy subjects. Results from this study show that mechanically induced pain is well suited for use in ASL FMRI experiments. In Chapter 3, we compare currently available ASL FMRI approaches for investigating tonic states, using a range of sensory paradigms. Results from these experiments support the use of an optimised version of Continuous ASL (CASL) FMRI to obtain whole-brain perfusion. Additionally, we discuss our decision to proceed with the newly acquired pseudo-continuous ASL (pCASL); a novel ASL technique that benefits from maximal signal-to-noise (SNR) across a whole-brain volume. In Chapter 4 we implement the pCASL FMRI approach to image the neural correlates of ongoing experimental pain. Results from the investigation of parametrically modulated ongoing mechanical pain show robust pain-related activation of key pain related regions that are monotonically active with an increase in stimulus intensity. Additionally, data from this experiment shows the presence of complex perfusion dynamics relative to pain worthy of further study. In Chapter 5, we optimised the pCASL sequence to obtain absolute perfusion changes across the whole-brain volume, using multi-inversion times, so that we could investigate the perfusion dynamics observed in Chapter 4. Results show that absolute perfusion changes during tonic pain are considerably less than for regions recruited during a non- pain task. Additionally, dynamic perfusion changes show complex stimulus responses across all active regions regardless of stimulus type. We conclude that while the technique is well suited to quantify absolute perfusion, the mechanisms underlying the dynamic changes in CBF (neuronal signal, neurovascular coupling) need further study. Finally, in Chapter 6, we implement the absolute perfusion approach developed in Chaper 5 to interrogate the neural correlates of the genetic pain disease, Erythromelalgia, and pleasurable relief. The results of this study show pain-related activation (and relief-induced reduction) of key pain-related regions. We conclude from these results that the ASL technique developed over the course of this thesis can be used to study a range of pain pathologies. Taken together, the results of this thesis document the development of a powerful perfusion imaging technique capable of quantifying absolute perfusion changes across a whole-brain volume. The data presented here from investigations of both experimental and pathological pain states supports the use of this technique in future tonic pain studies, as well as other neuroscience applications. We are confident that implementation of this imaging approach will provide integral insight into the mechanisms of ongoing pain states; and further the development of novel efficacious pain treatment options.
307

Étude de l'activité spontanée dans la moëlle épinière de l'oppossum Monodelphis domestica en développement

Lavallée, Annie January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.
308

La spectrométrie de masse appliquée à la quantification des protéines médicaments dans le plasma

Xuereb, Fabien 01 December 2008 (has links)
Le nombre croissant de médicaments protéiques utilisés en thérapeutique a créé des besoins dans le domaine de leur quantification, principalement dans le plasma, un milieu de composition protéique complexe. Le dosage, essentiel aux études pharmacocinétique/pharmacodynamique, ainsi qu’à l’optimisation de ces traitements, est compliqué par la nature protéique de ces médicaments et par les faibles concentrations auxquelles ils sont attendus dans ces milieux complexes. La méthodologie proposée se démarque des méthodes de dosage usuelles par son caractère universel. Elle fait appel à la spectrométrie de masse adaptée à la quantification des protéines grâce à l’utilisation d’un marquage isotopique différentiel des peptides : après enrichissement et protéolyse, l’échantillon à doser est marqué sur les lysines par la version légère d’un réactif de dérivation. En parallèle, les peptides de la protéine médicament pure marqués par la version lourde du réactif, servent d’étalon interne. La possibilité de quantifier la protéine à partir de plusieurs de ses peptides améliore la fiabilité du dosage. Appliquée à l’epoetin beta aux concentrations attendues en thérapeutique (autour de 0,5 femtomole/µL de plasma), la stratégie proposée permet de situer la limite de quantification à environ 50 attomoles d’epoetin beta/µL de plasma avec une méthodologie de spectrométrie de masse nano-LC-ESI-Q-TRAP fonctionnant en mode MRM. Pour étendre l’universalité de cette approche au champ des protéines médicaments pégylées, une seconde molécule a été étudiée. Il s’agit de l’interféron alfa-2b pégylé qui a permis de mettre en place une stratégie d’extraction spécifique du médicament utilisant sa pégylation. / The growing number of therapeutic proteins has created needs in the field of their quantification, mainly in plasma, which is a complex protein environment. Quantitative analysis of these proteins is essential for pharmacokinetics/pharmacodynamics studies, and for the optimization of treatments. However, the nature itself of the analyte and the low concentrations that are expected in plasma complicate the quantitative analysis. The proposed methodology differs from usual methods on its universal applicability. It relies on mass spectrometry adapted to the quantification of proteins by using peptides differential isotope labelling : after enrichment and proteolysis, the therapeutic protein and the plasmatic proteins are labelled on lysine residues by the light reagent. In parallel, peptides of the pure therapeutic protein, labelled by heavy version of reagent, are used as internal standard. The ability to quantify the protein with several of its peptides improves the reliability of the analysis. When applied to epoetin beta at expected therapeutic concentrations (about 0.5 femtomole/µL of plasma), the proposed strategy leads to a quantification limit close to 50 attomoles of epoetin beta/µL plasma, with a nano-LC-ESI-Q-TRAP mass spectrometry methodology operating in MRM. To extend the universal character of this approach to the field of pegylated protein drugs, a second therapeutic protein model has been studied. This model is a pegylated interferon alfa-2b which allowed developing a strategy for specific extraction of the drug relying on its pegylation.
309

Détection et suivi en IRM du macrophage polarisé et marqué aux nanoparticules de fer dans l’athérosclérose et l’imagerie de l’inflammation / MRI Detection and tracking of M1 polarized macrophage labelled with iron nanoparticles for atherosclerosis and inflammation imaging

Bessaad, Mohamed El Amine 24 March 2010 (has links)
L’athérosclérose est une maladie inflammatoire, caractérisée par une accumulation lipidique et cellulaire, dont le macrophage est l’acteur principal. Dans l’athérosclérose, le macrophage sécrète des cytokines qui favorisent le chimiotactisme et donc la migration et l’internalisation des cellules immunitaires, accentuant le processus pro-inflammatoire et accélérant l’évolution des plaques athéromateuses et leur instabilité jusqu’à éventuellement la rupture et/ou la formation de thrombus. Il est donc important de développer une technique d’imagerie cellulaire permettant de visualiser les macrophages et leur migration dans divers contextes pathologiques pour mieux comprendre leur implication, permettre le suivi thérapeutique et probablement leur utilisation dans la thérapie vectorisée. Le but de ce travail vise principalement à marquer aux nanoparticules de fer des macrophages activés de manière classiques (macrophages dits « M1 ») pour l’évaluation du statut inflammatoire dans un premier temps au sein des plaques d’athérome, et la visualisation de la dynamique de leur recrutement par IRM. Dans un deuxième temps, la méthode est exploitée pour montrer in vivo l’effet d’un traitement permettant de diminuer l’inflammation dans la plaque chez des souris invalidées pour le gène de l’apolipoprotéine E (ApoE-/-). Enfin, l’utilisation du protocole de marquage des macrophages M1 et leur suivi par IRM sont appliqués au diagnostic par imagerie d’une inflammation transitoire et circonscrite au poumon, induite par les lipopolysaccharides (LPS). En conclusion, le marquage des monocytes dirigés vers la voie M1 pour leur détection par IRM représente une méthode solide pour étudier différents phénomènes immunologiques en particulier le processus inflammatoire, et peut être un outil ou une approche de vectorisation permettant le suivi thérapeutique, cellulaire ou génique / Atherosclerosis is an inflammatory disease characterized by vessel wall lipids and cells accumulation, for which the macrophage acts as a central actor. In atherosclerosis the macrophage secretes cytokines that promote chemotaxis and thus migration and internalization of immune cells. This phenomenon emphasizes pro-inflammatory processes and accelerates the development of atherosclerotic plaque unstability to potentially its rupture with or without thrombus formation. It is therefore important to develop a technique for cell imaging to visualize macrophages and their migration in various pathological contexts to better understand their involvement, to allow therapeutic drug monitoring and probably their use in vectorized therapy. The aim of this work is mainly to label activated macrophages in classical way (macrophages called "M1") by iron nanoparticles, first to evaluate the inflammatory status within atherosclerotic plaques, and visualize their dynamic recruitment by MRI. In a second step, the method is used to show in vivo the effect of a treatment to reduce inflammation in the plaque, in mice invalidated for the gene for apolipoprotein E (ApoE-/ -). Finally, the protocol for M1 macrophages labelling and MRI tracking, was used for diagnostic imaging of a transient inflammation confined to the lung induced by lipopolysaccharide (LPS). In conclusion, the labelling of monocytes headed towards M1 polarization for their detection by MRI is a robust method to study various immunological phenomena in particular the inflammatory process, and can be an approach to vectorization and monitoring for gene or cell therapy
310

Peptide und Peptidnukleinsäuren zur Markierung und Organisation von Rezeptoren auf lebenden Zellen

Gröger, Katharina 14 August 2018 (has links)
Nukleinsäuren und Peptide erlauben es, Kontrolle über molekulare Prozesse auszuüben. In dieser Arbeit werden strukturgebende Elemente wie Coiled-Coil-Peptide oder PNA∙DNA-Strukturen genutzt, um Rezeptoren auf lebenden Zellen zu markieren und in ihrem Verhalten zu modulieren, oder cytosolische Proteine in ihrem Bindungsverhalten zu steuern. Im ersten Konzept wird die Interaktion des Coiled-Coil-Paars K3/E3 genutzt, um eine Transferreaktion, in welcher eine PNA-Sequenz vom K3-Donor auf den E3-Akzeptor übertragen wird, zu induzieren. Durch die Fusion des Akzeptorpeptids mit einem Rezeptor werden kovalente PNA-Rezeptorkonjugate auf der Oberfläche lebender Zellen geschaffen. Die Reaktion zwischen Thiol und Thioester erlaubt dabei einen schnellen Transfer. So wurden Rezeptoren aus der Familie der GPCR sowie der EGFR mit einem PNA-Strang versehen und durch fluoreszente PNA oder DNA selektiv markiert. Zusätzlich wurden verzweigte DNA-Architekturen mit mehreren Fluorophoren genutzt, um die Helligkeit der Markierung quantitativ zu erhöhen. Die PNA-EGFR-Konjugate wurden durch eine zwei Rezeptoren verbrückende Cy3-DNA adressiert und so zeitgleich markiert und dimerisiert. Dadurch wurde die Rezeptoraktivität gesteigert, was über Western Blot-, Immunofluoreszenz- und Fluoreszenzmikroskopieanalyse belegt wurde. In weiteren Ansätzen wurden Coiled-Coil-Systeme genutzt, um i) parallel zwei verschiedene Akzeptorpeptide mit verschiedenen Fluorophoren zu markieren und ii) Coiled-Coil-Peptide schaltbar zu machen. Durch die asymmetrische Verlängerung von K3/E3-Paaren mit Coiled-Coil-Sequenzen kann die Interaktion der Peptide an und aus geschaltet werden. Dies wurde sowohl in einem Fluoreszenzassay als auch in einer direkten Anwendung an der Syk-Kinase demonstriert. Die Liganden der Kinase wurden an den schaltbaren Peptiden angebracht und so die Affinität zur Syk-Kinase kontrolliert. / Nucleic acids and peptides can be used to obtain control over molecular processes within living cells. In this work, structural elements as coiled-coil peptides or PNA∙DNA-structures were used to label and modulate receptor behavior on living cells and to control ligand binding of cytosolic proteins. For the first concept the K3/E3-coiled-coil peptide pair was used to establish a proximity-guided, covalent transfer of a PNA strand from a K3-donor peptide onto the complementary E3-acceptor peptide. By fusion of the acceptor peptide to a receptor, PNA-receptor-conjugates were generated selectively on living cells. The native chemical ligation type of reaction allowed a fast PNA-transfer within minutes. Receptors from the family of GPCRs and the EGFR were tagged with a PNA-sequence and subsequently labeled by the addition of a fluorescent DNA or PNA. By recruiting branched DNA architectures which were decorated with several fluorophores, the total brightness of the labeling was increased quantitatively. A twice complementary Cy3-DNA was used to simultaneously label and dimerize the EGFR. Thereby, an artificially induced increase in receptor activity could be achieved, which was shown in Western Blot and immunofluorescence analysis as well as in fluorescence microscopy. In two other approaches coiled-coil peptides were used to i) label two different acceptor peptides simultaneously with two different dyes and ii) introduce coiled-coil peptides as part of a dynamic switchable system. Using an asymmetric coiled-coil elongation on the K3/E3 pair the interaction of both can be turned on and off. This was demonstrated in a fluorescence assay and applied to the Syk kinase, were Syk ligands were attached to the switchable peptides. Those ligands were changed from a bi- to a monovalent presentation status and thus the affinity of the Syk kinase towards its ligands can be controlled.

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