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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.
161

Beyond Good and Evil : An essay on the combination of ideas and aesthetics in George Bernard Shaw's Mrs Warren’s Profession

Susic, Semir January 2008 (has links)
<p>The objective of this essay is to approach a larger comprehension of the drama of George Bernard Shaw. The essay studies the combination of ideas and aesthetics in the play Mrs Warren’s Profession; how theatrical and mainly literary aesthetics interplay with political ideas and what the consequence of this combination is. The study illustrates that the dramatic method consists of using ideas as effective theatrical tools to move the reader/viewer by thought and not by sentiment. The study also illustrates that a key to understanding Shaw’s drama can be found in the construction of operas and symphonies; musical theoretic constructions are an integrated dramatic technique in Mrs Warren’s Profession. The study shows that it is a play with a political and social purpose; to raise awareness of the mechanisms of prostitution. The play does not use simplifications in terms of good and evil. It questions conventionality, unveils social hypocrisy and attempts to disillusion the reader/viewer. The antithesis between realism and idealism is an important source of dynamics and constitutes one of the principal aesthetical constructions.</p>
162

Inhibition of PDGF receptor signaling in tumor stroma : Effects on interstitial hypertension, drug uptake and therapeutic response

Pietras, Kristian January 2002 (has links)
<p>The role of platelet-derived growth factor (PDGF) in malignancies involves both autocrine and paracrine stimulation of cells within the tumor. The interstitial fluid pressure (IFP) is one of the forces that govern the transvascular flow of fluids. In both experimental and clinical cancers, the IFP is elevated and is thought to act as a barrier for delivery of drugs. Increasing evidence points to PDGF as a positive regulator of the interstitial fluid pressure in loose connective tissue. In this thesis, the effect of PDGF receptor inhibition on the tumor IFP, transvascular transport and efficacy of anti-cancer drugs is investigated.</p><p>All studies were performed using tumor models that display extensive tumor stroma and PDGF receptor expression restricted to stroma cells. Blocking of PDGF receptor signaling significantly reduced the tumor IFP in various tumor models. In parallel, pre-treatment with PDGF antagonists increased the tumor content of cytotoxic agents without affecting the uptake in other organs. Moreover, combination treatment with PDGF receptor inhibitors and chemotherapeutic agents dramatically enhanced the anti-tumor effects of the cytotoxic drugs, whereas treatment with only PDGF receptor inhibitors did not affect the growth of the tumors. Beneficial effects on the tumor reponse to radioimmunotherapy were also produced after concomitant administration of PDGF antagonists. Importantly, anti-angiogenic effects, changes in cell composition and increased tumor cell sensitivity to cytotoxic agents were ruled out as the cause for the synergistic effects. </p><p>Studies with different temporal scheduling of PDGF receptor inhibitors demonstrated a perfect correlation between a reduced IFP, an increased transvascular transport and an enhanced therapeutic effect of cytotoxic drugs, strongly suggesting that the phenomena are causally linked.</p><p>The studies presented herein illustrate for the first time the potential of cells in the stroma compartment as a target for efforts to treat cancer. In conclusion, a novel, possibly general, strategy to enhance the effects of conventional anti-cancer drugs has been identified.</p>
163

Application of a New Logic to Old Drugs: Angiogenesis Inhibition in Neuroblastoma

Svensson, Åsa January 2003 (has links)
<p>Neuroblastoma is one of the most common solid cancers of early childhood. In Sweden, approximately 10-15 cases occur annually. The overall five-year neuroblastoma survival in Europe is approximately 45%. Since cancer treatment involves drugs with risks of side effects in the growing child, there is a need for more effective and less toxic drugs. One new approach in cancer treatment is inhibition of tumor angiogenesis, i.e., of new blood vessel growth into the tumor. An angiogenesis inhibitor may be combined with cytostatic drugs to enhance the efficacy. The aim of this study was to investigate how drugs could be used to inhibit angiogenesis and tumor growth in a xenograft model of human neuroblastoma in nude mice. </p><p>The tumors express the angiogenesis stimulator vascular endothelial growth factor (VEGF) on both protein and mRNA levels. The angiogenesis inhibitors SU5416 (an inhibitor of VEGF signalling) and TNP-470 (an inhibitor of endothelial cell proliferation) inhibited angiogenesis in our model. TNP-470, however, inhibited angiogenesis without significant reduction of the tumor growth, in contrast to SU5416. </p><p>We also discovered that the cytostatic drug CHS 828 could cause regression of neuroblastoma tumors in the model when given orally at a low daily dose, alone or in combination with the angiogenesis inhibitor SU5416 or TNP-470. </p><p>Furthermore, a new use of the cardiac glycoside digoxin was found. Digoxin inhibited FGF-2 -stimulated bovine capillary endothelial cell growth in vitro, and inhibited angiogenesis in vivo in the chick chorioallantoic membrane assay (CAM). It also inhibited neuroblastoma growth by approximately 50% in our neuroblastoma model. </p><p>In conclusion, CHS 828 and digoxin represent two classes of drugs with potent antitumor effects that may be valuable in treatment of neuroblastoma, either alone or in combination with angiogenesis inhibitors.</p>
164

International entrepreneurship in networks : the impact of network knowledge combination on SMEs’ business creation in foreign markets

Tolstoy, Daniel January 2010 (has links)
Small and medium-sized enterprises (SMEs) face numerous challenges to stay competitive in the international marketplace. They have to align their business models to suit the needs and wants of customers in different markets. They also have to counter the competition of larger, more affluent firms. To meet these challenges, firms must continually create new business solutions. Whereas larger firms may tap into extensive internal knowledge bases for business creation, SMEs often have to reach outside themselves for creative input. This thesis contends that international entrepreneurship can be fostered in constellations of firms and individuals; in some instances, it may even be more accurate to talk about entrepreneurial networks than about entrepreneurial firms. The bedrock assumption of this thesis is that entrepreneurial opportunities are virtually ingrained in the network structure. Relationships across national borders provide multiple avenues for knowledge to intersect, thus creating new business solutions. It is argued that the internationalization of SMEs can unfold as an ongoing pursuit of entrepreneurial opportunities that emerge in everchanging networks. The findings suggest that network knowledge combination can be addressed as a capability that strongly shapes SMEs’ competitiveness in foreign markets. / <p>Diss. Stockholm : Handelshögskolan, 2010</p>
165

Inhibition of PDGF receptor signaling in tumor stroma : Effects on interstitial hypertension, drug uptake and therapeutic response

Pietras, Kristian January 2002 (has links)
The role of platelet-derived growth factor (PDGF) in malignancies involves both autocrine and paracrine stimulation of cells within the tumor. The interstitial fluid pressure (IFP) is one of the forces that govern the transvascular flow of fluids. In both experimental and clinical cancers, the IFP is elevated and is thought to act as a barrier for delivery of drugs. Increasing evidence points to PDGF as a positive regulator of the interstitial fluid pressure in loose connective tissue. In this thesis, the effect of PDGF receptor inhibition on the tumor IFP, transvascular transport and efficacy of anti-cancer drugs is investigated. All studies were performed using tumor models that display extensive tumor stroma and PDGF receptor expression restricted to stroma cells. Blocking of PDGF receptor signaling significantly reduced the tumor IFP in various tumor models. In parallel, pre-treatment with PDGF antagonists increased the tumor content of cytotoxic agents without affecting the uptake in other organs. Moreover, combination treatment with PDGF receptor inhibitors and chemotherapeutic agents dramatically enhanced the anti-tumor effects of the cytotoxic drugs, whereas treatment with only PDGF receptor inhibitors did not affect the growth of the tumors. Beneficial effects on the tumor reponse to radioimmunotherapy were also produced after concomitant administration of PDGF antagonists. Importantly, anti-angiogenic effects, changes in cell composition and increased tumor cell sensitivity to cytotoxic agents were ruled out as the cause for the synergistic effects. Studies with different temporal scheduling of PDGF receptor inhibitors demonstrated a perfect correlation between a reduced IFP, an increased transvascular transport and an enhanced therapeutic effect of cytotoxic drugs, strongly suggesting that the phenomena are causally linked. The studies presented herein illustrate for the first time the potential of cells in the stroma compartment as a target for efforts to treat cancer. In conclusion, a novel, possibly general, strategy to enhance the effects of conventional anti-cancer drugs has been identified.
166

Application of a New Logic to Old Drugs: Angiogenesis Inhibition in Neuroblastoma

Svensson, Åsa January 2003 (has links)
Neuroblastoma is one of the most common solid cancers of early childhood. In Sweden, approximately 10-15 cases occur annually. The overall five-year neuroblastoma survival in Europe is approximately 45%. Since cancer treatment involves drugs with risks of side effects in the growing child, there is a need for more effective and less toxic drugs. One new approach in cancer treatment is inhibition of tumor angiogenesis, i.e., of new blood vessel growth into the tumor. An angiogenesis inhibitor may be combined with cytostatic drugs to enhance the efficacy. The aim of this study was to investigate how drugs could be used to inhibit angiogenesis and tumor growth in a xenograft model of human neuroblastoma in nude mice. The tumors express the angiogenesis stimulator vascular endothelial growth factor (VEGF) on both protein and mRNA levels. The angiogenesis inhibitors SU5416 (an inhibitor of VEGF signalling) and TNP-470 (an inhibitor of endothelial cell proliferation) inhibited angiogenesis in our model. TNP-470, however, inhibited angiogenesis without significant reduction of the tumor growth, in contrast to SU5416. We also discovered that the cytostatic drug CHS 828 could cause regression of neuroblastoma tumors in the model when given orally at a low daily dose, alone or in combination with the angiogenesis inhibitor SU5416 or TNP-470. Furthermore, a new use of the cardiac glycoside digoxin was found. Digoxin inhibited FGF-2 -stimulated bovine capillary endothelial cell growth in vitro, and inhibited angiogenesis in vivo in the chick chorioallantoic membrane assay (CAM). It also inhibited neuroblastoma growth by approximately 50% in our neuroblastoma model. In conclusion, CHS 828 and digoxin represent two classes of drugs with potent antitumor effects that may be valuable in treatment of neuroblastoma, either alone or in combination with angiogenesis inhibitors.
167

Synthesis And Characterization Of Fluorescent Zinc Phthalocyanine Pigments And Its Combination Pigment With Mica Titania Pig Ment

Kahya, Sevinc Sevim 01 September 2012 (has links) (PDF)
In the present work, zinc phthalocyanine and tetra nitro substituted zinc phthalocyanine were sytnhesized by using phthalic anhydride and nitro phthalic acid precursor respectively under microwave irradiation. Molecular structures of these pigments were confirmed by FT-IR and UV-visible spectroscopy analyses. Furthermore, these pigments were deposited on mica-titania pigment substrate in dimethyl formamide solvent to obtain the combination pigment. FT-IR analysis was conducted to analyze the deposition of pigments onto the mica-titania surfaces. Fluorescence spectroscopy analysis was performed to observe zinc phthalocyanine, tetra nitro zinc phthalocyanine pigments, and their combination pigment with mica- titania pigments. The surface morphologies of zinc phthalocyanines on the mica titania pigments were investigated by scanning electron microscopy. Optimum deposition temperature and deposition time were determined by v depositing varying amounts of zinc phthalocyanines. The paint samples of these combination pigments were prepared by alkyd based paint formulation. L*a*b* values of the paint samples were determined by color measuring spectrophotometry. The optimum deposition temperature was determined as 120 oC and the optimum deposition time was determined as half an hour and effective deposition was obtained at 120 &deg / C. It is observed that, with the increasing amount of ZnPc, the interaction between ZnPc particles increases and they desorp the surface of mica-titania pigment. The best result was obtained with 0.08 g ZnPc at 120 oC.
168

Experimental radioimmunotherapy and effector mechanisms

Eriksson, David January 2006 (has links)
Radioimmunotherapy is becoming important as a new therapeutic strategy for treatment of tumour diseases. Lately monoclonal antibodies tagged with radionuclides have demonstrated encouraging results in treatment of hematological malignancies. The progress in treatment of solid tumours using radioimmunotherapy, however, has been slow. New strategies to improve the treatment response need to be evaluated. Such new strategies include the combination of radioimmunotherapy with other treatment modalities but also elucidation and exploration of the death effector mechanisms involved in tumour eradication. As the combination of radioimmunotherapy and radiotherapy provides several potential synergistic effects, we started out by optimising a treatment schedule to detect benefits combining these treatment modalities. An anti-cytokeratin antibody labelled with 125I administered before, after, or simultaneously with radiotherapy, indicated that the highest dose to the tumour was delivered when radiotherapy was given prior to the antibody administration. The optimised treatment schedule was then applied therapeutically in an experimental study on HeLa Hep2 tumour bearing nude mice given radiotherapy prior to administration of 131I-labelled monoclonal antibodies. Combining these treatment regimes enhanced the effect of either of the treatment modalities given alone, and a significant reduction in tumour volumes could be demonstrated. This treatment caused a dramatic change in tumour morphology, with increased amounts of connective tissue, giant cells and cysts. Furthermore cellular alterations like heterogeneity of nuclear and cytoplasmic size and shape were observed, and at least a fraction of the tumour cells presented some characteristics of apoptosis. The induced sequential events in Hela Hep2 cells exposed to 2.5-10 Gy of ionizing radiation were studied further, with special emphasis on cell cycle arrest, mitotic aberrations and finally cell death. Following radiation HeLa Hep2 cells initiated a transient G2/M arrest trying to repair cellular damage. This arrest was followed by a sequence of disturbed mitoses with anaphase bridges, lagging chromosomal material, hyperamplification of centrosomes and multipolar mitotic spindles. These mitotic disturbances produced multinuclear polyploid cells and cells with multiple micronuclei, cells that were destined to die via mitotic catastrophes and delayed apoptosis. Induction of apoptosis in HeLa Hep2 cells following radiation doses and dose-rates equivalent to those delivered at radioimmunotherapy was concurrently studied in vitro. Significant induction of apoptosis was obtained and found to be induced relatively slowly, peaking 72-168 hours post irradiation. Caspases from the intrinsic pathway as well as the extrinsic pathway were found to be activated in response to ionizing radiation. Furthermore caspase-2, which has recently been acknowledged for its role as an initiator caspase was found to be activated following radiation and seems to play an important role in this delayed apoptosis.
169

A Division-of-Labor Hypothesis : Adaptations to Task Structure in Multiple-Cue Judgment

Karlsson, Linnea January 2007 (has links)
Judgments that demand consideration of pieces of information in the environment occur repeatedly throughout our lives. One professional example is that of a physician that considers multiple symptoms to make a judgment about a patient’s disease. The scientific study of such, so called, multiple-cue judgments that involve multiple pieces of information (cues: e.g., symptoms) and continuous criterion (e.g., blood pressure) has been concerned with the statistical modelling of judgment data (see Brehmer, 1994; Cooksey, 1996; Hammond &amp; Stewart, 2001). In this thesis behavioural experiments, cognitive modelling and brain imaging is used to investigate an adaptive division of labor between multiple memory representations in multiple-cue judgment. It is hypothesized that the additive, independent linear effect of each cue can be explicitly abstracted and integrated by a serial, additive judgment process (Einhorn, Kleinmuntz, &amp; Kleinmuntz, 1979). It is further hypothesized that a variety of sophisticated task properties, like non-additive cue combination, nonlinear relations, and inter-cue correlation, are carried implicitly by exemplar-memory (Medin &amp; Schaffer, 1978; Nosofsky, 1984; Nosofsky &amp; Johansen, 2000). Study I and II investigates the effect of additive versus non-additive cue-combination and verify the predicted shift in cognitive representations as a function of the underlying cue-combination rule. The third study is a review that discusses the nature of these representational shifts; are they contingent upon early perceived learning performance instead of automatic and error-driven? Study IV verifies that this shift is evident also in the neural activity associated with making judgments in additive and non-additive tasks.
170

Beyond Good and Evil : An essay on the combination of ideas and aesthetics in George Bernard Shaw's Mrs Warren’s Profession

Susic, Semir January 2008 (has links)
The objective of this essay is to approach a larger comprehension of the drama of George Bernard Shaw. The essay studies the combination of ideas and aesthetics in the play Mrs Warren’s Profession; how theatrical and mainly literary aesthetics interplay with political ideas and what the consequence of this combination is. The study illustrates that the dramatic method consists of using ideas as effective theatrical tools to move the reader/viewer by thought and not by sentiment. The study also illustrates that a key to understanding Shaw’s drama can be found in the construction of operas and symphonies; musical theoretic constructions are an integrated dramatic technique in Mrs Warren’s Profession. The study shows that it is a play with a political and social purpose; to raise awareness of the mechanisms of prostitution. The play does not use simplifications in terms of good and evil. It questions conventionality, unveils social hypocrisy and attempts to disillusion the reader/viewer. The antithesis between realism and idealism is an important source of dynamics and constitutes one of the principal aesthetical constructions.

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