Moving lipids : ceramides, glycosphingolipids and the glycolipid transfer protein

Lipid movement in cells occurs by a variety of methods. Lipids diffuse freely along the lateral plane of a membrane and can translocate between the lipid leaflets, either spontaneously or with the help of enzymes. Lipid translocation between the different cellular compartments predominantly takes place through vesicular transport. Specialized lipid transport proteins (LTPs) have also emerged as important players in lipid movement, as well as other cellular processes. In this thesis we have studied the glycolipid transport protein (GLTP), a protein that transports glycosphingolipids (GSLs). While the in vitro properties of GLTP have been well characterized, its cell biological role remains elusive. By altering GSL and GLTP levels in cells, we have extracted clues towards the protein's function. Based on the results presented in this thesis and in previous works, we hypothesize that GLTP is involved in the GSL homeostasis in cells. GLTP most likely functions as a transporter or sensor of newly synthesized glucosylceramide (GlcCer), at or near the site of GlcCer synthesis. GLTP also seems to be involved in the synthesis of globotriacylceramide, perhaps in a manner that is similar to that of the fourphosphate adaptor protein 2, another GlcCer-transporting LTP. Additionally, we have developed and studied a novel method of introducing ceramides to cells, using a solvent-free approach. Ceramides are important lipids that are implicated in several cellular functions. Their role as proapoptotic molecules is particularly evident. Ceramides form stable bilayer structures when complexed with cholesterol phosphocholine (CholPC), a large-headgroup sterol. By adding ceramide/CholPC complexes to the growth medium, various chain length ceramides were successfully delivered to cells in culture. The uptake rate was dependent on the chain length of the ceramide, where shorter lipids were internalized more quickly. The rate of uptake also determined how the cells metabolised the ceramides. Faster uptake favored conversion of ceramide to GlcCer, whereas slower delivery resulted mainly in breakdown of the lipid.

Understanding round-tripping phenomenon in Russian context – case Cyprus

Russian FDI has a few peculiarities. One of them is round-tripping. Round-tripping is defined as transfer of funds abroad, usually to offshore financial centers (OFCs), and then bringing all or some of the investment back as foreign investment. Russian context was chosen for this study because the share of round-tripping investments from country’s total FDI is extensive. However, it needs to be addressed that this is not just a Russian phenomenon. Round-tripping is used by many developed and developing countries, and most of the countries have their own designated destinations for this kind of capital, much like Cyprus is the main destination for Russian capital. It is important to study this phenomenon further, since it falsifies FDI statistics and can lead to poor decisions on state level. Theoretical part of the study tries to determine weather traditional FDI and internationalization theories fit to explain the Russian round-tripping phenomenon. Traditional FDI and internationalization theories are first introduced in general terms, and then further examined in Russian context. In traditional endogenic FDI theories, when the capital is formed in one country it goes abroad to find better profits. At a first glance, this seemed not to be the case in round-tripping. However, during the study it became rather clear that with few adjustments and changes in perspective, traditional theories could be used to explain round-tripping phenomenon. For example, OLI paradigm can be further developed into OLIH paradigm with ‘H’ representing the important home country institutions. Transaction based view and resource seeking theories were also seen well equipped to explain round-tripping with a change in perspective. The latter part of the study focused on holistic understanding of Russian –Cyprian investment relationship. Study aims to shed light into the determinants and consequences of this phenomenon for both countries involved. The two share historical, cultural and political ties, but most importantly common financial interests. Russian companies seek security and financial knowledge to maneuver their assets and Cyprian economy largely is dependent on their disproportionally large financial sector. Consequences for Cyprian economy were seen in current economic crisis, when the need for their financial services diminished. Russian government on the other hand is losing vast amounts of tax money due to this phenomenon. A rather extreme view was also introduced in this study. Round-tripping phenomenon and OFCs are an important reason why corruption exists, since if one does not have a way to make ill-gained money legitimate why try to ill-gain the money at the first place. The most important finding of the study is that round-tripping companies are in a better competitive position than genuine and purely domestic investor due to their institutional knowledge.

Mass transfer and reaction kinetics in single droplet systems

As reactive extraction grown more and more popular in a variety of technological applications, optimizing its performance becomes more and more important. The process of complex formation is affected by a great number of both physical and chemical properties of all the components involved, and sometimes their interference with one another makes improving the effectiveness of such processes very difficult. In this Master’s Theses, the processes of complex formation between the aqueous phase - represented by copper sulfate water solution, and organic phase – represented by Acorga M5640 solvent extractor, were studied in order to establish the effect these components have on reactive extraction performance and to determine which step is bottlenecking the process the most.

Tourism and the precautionary principle : a survey of academic and government stakeholders

The purpose of this exploratory investigation was to provide a more precise understanding and basis from which to assess the potential role of the precautionary principle in tourism. The precautionary principle, analogous to the ideal of sustainable development, is a future-focused planning and regulatory mechanism that emphasizes pro-action and recognizes the limitations of contemporary scientific methods. A total of 100 respondents (80 tourism academics, 20 regional government tourism officials) from Canada, United States, United Kingdom, Australia and New Zealand completed the webbased survey between May and June 2003. Respondents reported their understanding of the precautionary principle, rated stakeholder involvement and education strategies, assessed potential barriers in implementation, and appraised steps of a proposed fi-amework for implementation. Due to low sub sample numbers, measures of central tendency were primarily used to compare groups, while inferential statistics were applied when warranted. Results indicated that most respondents (79%) felt the principle could be a guiding principle for tourism, while local and regional government entities were reported to have the most power in the implementation process. Findings suggested close links between the precautionary principle and sustainability, as concern for future generations was the most critical element of the principle for tourism. Overall, tourism academics were more supportive of the precautionary principle in tourism than were regional government tourism officials. Only minor variation was found in responses among regional groups across all variables. This study established basic ground for understanding the precautionary principle in tourism and has been effective in formulating more precise questions for future research.

Comparing ESL electronic and face-to-face pre-writing conferences and first drafts : discourse, participation, and idea transfer /

This study was a comparative investigation of face-toface (i.e., proximate) and computer-mediated written (i.e., graphic) pre-writing conferences. The participants in this study were advanced English as a second language students. The 2 types of conferences were compared in terms of textual features, participation, and the . degree to which they were on topic. Moreover, drafts written after the 2 types of conferences were compared in terms of textual features, and the degree to which they were related to the conferences. Students produced an equivalent amount of discourse in an equivalent amount of time in the 2 types of conferences. The discourse in graphic conferences displayed greater lexical range, and some evidence suggests that it was less on-topic. Both these results likely occurred because the graphic conferences contained more discourse demonstrating interactive competence. Participation in graphic conferences was found to be as balanced or more balanced among students, and among students and the group leader combined. Overall, the drafts produced after the 2 types of conferences were of equivalent length and topical range, but some evidence suggests that drafts written after proximate conferences were more related to the conferences.

Legitimacy in question : elite-mass relations, constitutional reform and Canadian democracy /

During the 1980s and 1990s, Canadian political authority orientations underwent a significant transformation. Canadians are no longer deferential towards their political elites. Instead, they are autonomous, challenging, and increasingly participatory, and this continuing trend has brought the procedural legitimacy of the Canadian political process into question. The following study of elite-mass relations within Canadian democracy attempts to provide insight into the meaning of this change and how it should be addressed. An attitudinalbehavioural analysis ofthe electorate presents evidence that popular cynicism and alienation is rooted more deeply in a dissatisfaction with political institutions and traditions than with politicians. A structural analysis of the elected political elite reveals the failure of consociational traditions to provide effective representation as well as the minimal impact which the aforementioned orientation shift has had upon this elite. An event-decisional analysis, or case study, ofelite-mass relations in the arena of constitutional politics augments these complementary profiles and illustrates how the transformed electorate has significantly restricted the elected political elite's role in constitutional reform. The study concludes that the lack ofresponsiveness, representativeness, and inclusiveness ofCanada's elected political elite, political institutions, and political traditions has substantially eroded the procedural legitimacy of Canadian democracy during the 1980s and 1990s. Remedying these three deficiencies in the political system, which are the objects of increasing public demand, may restore legitimacy, but the likelihood that such reforms will be adopted is presently uncertain in the face of formidable difficulties and obstacles.

Limiting rights, Canadian style : the Supreme Court of Canada, American jurisprudence and section 1 of the Charter /

The addition of the Charter of Rights and Freedoms represented a fundamental shift in Canadian governance. Many saw the tabling of such a document as a further, even fmal, step towards the Americanization of the Canadian polity. While the Charter's presence has significantly altered the relationship between citizens, government and the courts, it has done so by maintaining the traditional values and experiences that has been the hallmarks of Canadian constitutionalism. This is in contrast to the fears harboured by critics suggesting that the Charter was a further Americanization of the Canadian Polity, notwithstanding the very different natures of the American Bill of Rights and the Canadian Charter. Analyzing American Supreme Court precedent use by the Canadian Supreme Court has demonstrated that such an Americanization has not, in fact, occurred. In the present analysis of American precedent use in section 1 limitation of rights cases, the citation of these precedents are at best episodic, at least on the quantitative level. Qualitatively, the Canadian Supreme Court generally uses American jurisprudence to further support broad definitions of 'great rights' . As for the more intricate details of rights limitations and the process involved in detennining how Charter rights are limited, one would be hard pressed to find even cursory references to American case law.

Using classroom meetings to transfer conflict resolution skills /

This study examined whether daily classroom meetings resulted in the positive transfer of conflict resolution information and skills beyond the formal classroom setting and into the classroom. A control group of sixteen Grade five students received three weeks of conflict resolution training and an experimental group of nineteen Grade five students fi-om the same school received three weeks of conflict resolution training followed by three additional weeks of class meetings. Pretest measures were taken via a scaled questionnaire and short answer questions before the conflict resolution lessons began for the following skills: knowledge of conflict resolution; conflict resolution behaviour; and attitude about using conflict resolution to resolve problems with other people. Posttest measures examined conflict resolution skills following involvement in the study. Students chosen randomly and both teachers were interviewed following the study. The teachers were again interviewed three months after the study. Teacher journal notes rounded out the data. The results of the study indicated that the Grade five boys who participated in three weeks of conflict resolution training did not increase their conflict resolution skills in any of the areas examined. Girls who participated in three weeks of conflict resolution training did not improve in two areas (i.e., behaviour, knowledge) and became less positive about using verbal mediation to resolve conflicts. The Grade five students who participated in three weeks of training and three weeks of class meetings obtained different results. The boys improved significantly in their ability to use verbal mediation to resolve conflicts and were more positive about verbal mediation. They did not become more knowledgeable about verbal mediation. The girls who participated in three weeks of training and three weeks of class meetings were more knowledgeable of conflict resolution and used conflict resolution to solve problems with other people. However, they were significantly less positive about using these skills to resolve problems.

Rights jurisprudence and the charter : evaluating the changing structure of Canadian federalism /

Abstract . Rights jiirisprudence in Canada dates back as far as Confederation in 1867. Between this date and 1982, the organizing principle of Confederation - federalism - has kept this jurisprudence solely within the supremacy of Parliament, subject to its confines and division of powers. After 1982, however, a new constitutional organizing principle was introduced, when Prime Minister Pierre Trudeau introduced the patriation initiative, touted as the "people's package". Individual rights and freedoms were now guaranteed by the Constitution. Citizens of Canada now had a direct link to the Constitution via the Charter and there were now two significantly different organizing principles within the constitutional order widch created an unstable coexistence. This instability has led to a clash between judicially enforced Charter rights and federalism. The Charter has since had both a nationalizing and centralizing effect on Canadian federalism. This thesis explores the relationship between rights and federalism in Canada fix)m Confederation to present day by comparing the jurisprudence of pre and post Charter Canada. An analysis of Supreme Court's (and its predecessor's, the JCPC) decisions shows the profound effect the Charter has had on Canadian federalism. The result has been an undermining of federalism in Canada, with Parliamentary Supremacy replaced by Constitutional supremacy, and ultimately. Judicial Supremacy. Moreover, rights discourse has largely replaced federalism discourse. Canadians have become very attached to their Charter, and are unwilling to allow any changes to the constitution that may affect their rights as political elites discovered the hard way after the collapse of the Meech and Charlottetown Accords. If federalism is to remain a relevant and viable organizing principle in the Constitution, then governments, especially at the provincial level, must find new and iimovative ways to assert their importance within the federation.

Investigation of the mechanism of transfer of a-tocopherol by the human a-tocopherol transfer protein (H-a-TTP) /

The human a-tocopherol transfer protein (h-a-TTP) is understood to be the entity responsible for the specific retention of a-tocopherol (a-toc) in human tissues over all other forms of vitamin E obtained from the diet. a-Tocopherol is the most biologically active form of vitamin E, and to date has been studied extensively with regard to its antioxidant properties and its role of terminating membrane lipid peroxidation chain reactions. However, information surrounding the distribution of a-tocopherol, specifically its delivery to intracellular membranes by a-TTP, is still unclear and the molecular factors influencing transfer remain elusive. To investigate the mechanism of ligand transfer by the h-a-TTP, a fluorescent analogue of a-toc has been used in the development of a fluorescence resonance energy transfer (FRET) assay. (/?)-2,5,7,8-tetramethyl-2-[9-(7-nitro-benzo[l,2,5]oxdiazol-4-ylamino)-nonyl]- chroman-6-ol (NBD-toc) has allowed for the development of the FRET-based ligand transfer assay. This ligand has been utilized in a series of experiments where changes were made to acceptor lipid membrane concentration and composition, as well as to the ionic strength and viscosity of the buffer medium. Such changes have yielded evidence supporting a collisional mechanism of ligand transfer by a-TTP, and have brought to light a new line of inquiry pertaining to the nature of the forces governing the collisional transfer interaction. Through elucidation of the transfer mechanism type, a deeper understanding of the transfer event and the in vivo fate of a-tocopherol have been obtained. Furthermore, the results presented here allow for a deeper investigation of the forces controlling the collisional protein-membrane interaction and their effect on the transfer of a-toc to membranes. Future investigation in this direction will raise the possibility of a complete understanding of the molecular events surrounding the distribution of a-toc within the cell and to the body's tissues.

Synthesis of fluorescent analogues of a-tocopherol as ligands for the human a-tocopherol transfer protein (a-TTP) /

To further understand in vivo localization and trafficking of a-tocopherol (a-Toe), the most biologically active form of vitamin E, between lipid environments, tocopherols are required that can be followed by teclu1iques such as confocal microscopy and fluorescence resonance energy transfer (FRET) assays. To this end, sixteen fluorescent analogues of a-tocopherol (la-d [(1)anthroy loxy -a-tocopherols, A O-a-Toes], 2a-d [w-nitro benzoxadiazole-a-tocopherols, NBD-aToes], 3a-d [w-dansyl-a-tocopherols, DAN-a-Toes], and 4a-d [w-N-methylanthranilamide-atocopherols, NMA-a-TocsD were prepared by substituting fluorescent labels at the terminus of w-functionalized alkyl chains extending from C-2 of the chroman ring while retaining key binding features of the natural ligand. These compounds were prepared starting from (S)-Trolox® acid VIa esterification, protection, and reduction producing the silyl-protected (S)-Trolox aldehyde that was coupled using Wittig chemistry to different w-hydroxyalkylphosphonium bromides. Reduction of the alkene generated the w-hydroxy functionalized 2-n-alkyl intermediates 9a-d having the necessary 2R stereochemistry. A series of functional group manipulations including mesylation, substitution with azide, and hydride reduction provided w-amino functionalized intermediates 12a-d as well. Coupling intermediates 9a-d and 12a-d with the selected fluorophores (9- anthracene carboxylic acid, 4-chloro-7-nitrobenz-2-oxa-l,3-diazole, 5- dimethylaminonapthalene-l-sulfonyl chloride, and I-methyl-2H-3,1-benzoxazine-2,4(1H)dione), followed by deprotection of the phenolic silyl group, gave the desired fluorescent ligands la-d, 2a-d, 3a-d and 4a-d in good yield. Assessment of their binding affinities with recombinant human a-tocopherol transfer protein (ha-TTP) utilizing fluorescent titration binding assays identified competent ligands for further use in protein studies. Compounds Id (C9-AO-a-Toc) and 2d (C9-NBD-a-Toc) both having nonyl alkyl chain extensions between the chromanol and fluorophore were shown to bind specifically to ha-TTP with dissociation constants (KdS) of approximately 280 nM and 55 nM respectively, as compared to 25 nM for the natural ligand 2R,4'R,^'R-a-tocophQxoL.

Acquisition and transfer of experiential learning from rock climbing to the corporate workplace

There were three purposes to this study. The first purpose was to determine how learning can be influenced by various factors i~ the rock climbing experience. The second purpose was to examine what people can learn from the rock climbing experience. The third purpose was to investigate whether that learning can transfer from the rock climbing experience to the subjects' real life in the workplace. Ninety employees from a financial corporation in the Niagara Region volunteered for this study. All subjects were surveyed throughout a one-day treatment. Ten were purposefully selected one month later for interviews. Ten themes emerged from the subjects in terms of what was learned. Inspiration, motivation, and determination, preparation, goals and limitations, perceptions and expectations, confidence and risk taking, trust and support, teamwork, feedback and encouragement, learning from failure, and finally, skills and flow. All participants were able to transfer what was learned back to the workplace. The results of this study suggested that subjects' learning was influenced by their ability to: take risks in a safe environment, fail without penalty, support each other, plan without time constraints, and enjoy the company of fellow workers that they wouldn't normally associate with. Future directions for research should include different types of treatments such as white water rafting, sky diving, tall ship sailing, or caving.