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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.
661

Invandrade invandrarkritiker? : Orsakerna till stödet för Sverigedemokraterna bland sympatisörer med utländsk bakgrund

Lundkvist, Adrian January 2018 (has links)
This bachelor’s thesis examines the causes behind the support of radical right and anti-immigration parties by those with a non-native background. Building on findings of previous research and the funnel of causality, a set of variables consisting of anti-immigration views and socio-economic factors are examined to determine their causal effect on the support for the Sweden Democrats among the non-native swedish population. Utilising data from Syd-SOM 2015 and Väst-SOM 2015, no support were found for the hypothesis that those with a non-native background support the Sweden Democrats on the basis of socio-economic factors. Support were found however for the hypothesis that anti-immigration views among non-natives are an important cause for their support of the Sweden Democrats.
662

Sveriges feministiska utrikespolitik : En jämförande innehållsanalys av svensk utrikespolitik mellan åren 2010–2018 / Sweden's feminist foreign policy : A comparative content analysis of Swedish foreign policy between 2010-2018

Örnros, Elsa January 2019 (has links)
In the year of 2014, the new Swedish government declared itself as the world’s first feminist government. This thesis aims to study the Swedish foreign policy and thus to investigate if the declared feminist foreign policy has resulted in a changed foreign policy. By using two feminist theories; radical feminism and liberal feminism, the study’spurpose is to do a critical comparison between the governmental administration of Fredrik Reinfeldt in the years of 2010-2014, with the administration of Stefan Löfven between 2014-2018. After a recently finished first term of the feminist policy, the subject of this study is interesting in the perspective of evaluation. To investigate if the policy by fact has changed, a qualitative textual analysis will be used. Further, to analyze the foreign policy, foreign declarations from all years between 2011-2018 will constitute the material. In summary, the result demonstrates that a change in policy has appeared and can further be ascertained. Both administrations show clear features of liberal feminism. However, during the last term, between 2014-2018, the governmental policy has shown tendencies of more radical feminist elements. Although the world’s first feministgovernment has received great attention, the future of the feminist foreign policy is still indeterminate.
663

Microwave-Promoted Iminyl Radical Cyclizations for the Synthesis of Azaheterocycles and the Total Synthesis of Yaku'amide A

Cai, Yu 01 August 2017 (has links)
Two different research projects are described in this dissertation. The first one focuses on microwave-promoted iminyl radical cyclization for the formation of azaheterocycles which are embedded within numerous pharmaceuticals and biologically active natural products (such as clindamycin, eletriptan, moxiflaxin, etc.). We are quite interested in this project because of the significance of nitrogen-containing heterocycles as pharmaceuticals and organocatalysts combined with the need for safe, simple, and economical means of constructing them. We have successfully developed an efficient one-step synthesis of 2-acylpyrroles and diastereoselective dihydropyrroles from readily available oxime ether substrates. This remarkably efficient and environmentally friendly methodology should be useful for rapid and easy preparation of potent drugs containing pyrrolidine ring systems. The second project focuses on the total synthesis of yaku'amide A. The natural compound, isolated from a marine sponge in 2010, is a medium-sized peptide that contains bulky dehydroamino acids. It has an excellent IC50 value (14 ng/mL) against leukemia cells, making it a promising anticancer agent. Because of the unique anticancer profile, potent bioactivity, and limited supply, the natural product was attractive to us for an efficient synthesis and mechanistic investigation. We have devised more efficient strategies compared to Inoue's methods for the synthesis of bulky ∆AAs and their incorporation into peptides, which are innovative and will allow us to synthesize yaku'amide A rapidly and conveniently. A one-pot sequence consisting Martin sulfurane mediated anti dehydration, azide reduction, and O→N acyl transfer was developed for the construction of E- and Z-dehydroisoleucine-containing peptides. We also developed a three-step synthesis of N-terminal acyl group involving a one-pot indium-catalyzed cross-Claisen condensation/reduction from a known compound. The most hindered coupling reaction of pentapeptide acid and nanapeptide amine in the late stage is accomplished. Our total synthesis of yaku'amide A can be completed in 19 longest linear steps and 66 total steps. Further identification of yaku'amide A for elucidation of its biological target and mode of action will be explored, which will open up new avenues in the fight against cancer.
664

Oxidative Damage to DNA 2´-Deoxyribose by Carbonate Radicals: Reaction Mechanisms and Products

Moore, Terence J 01 December 2014 (has links)
The carbonate radical anion (CO3•-, CR) is an important reactive oxygen species produced in vivo by one-electron oxidation of CO2 or bicarbonate, constituents of the major physiological buffer. It was demonstrated for the first time by using an HPLC-based analysis of low-molecular products of DNA damage that CRs react with DNA 2΄-deoxyribose by the hydrogen abstraction mechanism. CRs exhibit a ~ 800-fold preference for one-electron oxidation of guanine over hydrogen abstraction from DNA sugar, in sharp contrast with •OH. CRs also have, as compared to •OH, an increased preference for the H1΄ abstraction, which is the most thermodynamically favorable due to the highest stability of the respective deoxyribosyl radical but kinetically the slowest due to low solvent accessibility, by the expense of the decreased preference for the H5΄ abstraction. All these findings are in agreement with the characteristics of CR as a potent oxidant and selective hydrogen abstractor.
665

If I Had a Hammer: American Folk Music and the Radical Left

Kerley, Sarah C 01 December 2015 (has links)
Folk music is one of the most popular forms of music today; artists such as Mumford and Sons and the Carolina Chocolate Drops are giving new life to an age-old music. It was not until the 1950s that new popular interest in folk music began. Earlier, folk music was used by leftist organizations as a means to reach the masses. It assumed because of this history that many folk artists are sympathetic to the Left. By looking at the years from 1905-1975 with the end of the Vietnam War, this study hopes to present the notion that even though these artists produced music that promoted leftist ideals, they were not always supportive of the Communist Party and other leftist organizations. Specific artists will be examined, paying close attention to artists who not only produced revolutionary music, but who were also employed by leftist organizations to perform at rallies and meetings.
666

Computational Quantum Chemistry Studies of the Stabilities of Radical Intermediates Formed During the Oxidation of Melatonin

Warden, Constance E 01 December 2016 (has links)
Melatonin, a nontoxic natural antioxidant, is of interest as a possible spin trap for use in spectroscopic methods to observe and identify short-lived free radicals, which have been linked to oxidative stress that may result in serious health problems. However, the reaction mechanisms for the oxidation of melatonin to form the product N1-acetyl-N2-formyl-5-methoxykynuramine are still not well understood. Computational quantum chemistry studies have been done on four proposed reaction mechanisms, involving the following major intermediate structures: a dioxetane, an epoxide, a melatonin radical cation, and a spin radical adduct. Molecular geometries were optimized at the DFT/B3LYP/cc-pVTZ level of theory, and single point energies were extrapolated to the complete basis set limit at the Hartree-Fock and second-order Møller-Plesset perturbation levels of theory using the cc-pVXZ (X = D, T, Q) basis sets. The lowest energy pathway was found to be the single electron transfer pathway, involving the melatonin radical cation intermediate.
667

Synthèse et étude physico-chimique de nouvelles alcoxyamines activables pour la lutte contre le paludisme / Study and synthesis of activatable alcoxyamines to fight malaria

Nkolo, Paulin 27 September 2017 (has links)
Ce travail présente une nouvelle application des alcoxyamines en chimie thérapeutique et notamment pour lutter contre le parasite plasmodium falciparum, responsable du paludisme.Cette idée repose sur l'utilisation de la chimie radicalaire. A ce jour un traitement de choix met en œuvre l'artémisinine. Le mode d'action est la destruction du parasite par la formation de radicaux libres. L'artémisinine est activée par le Fe(II) de l'hème libéré lors de la digestion de hémoglobine par le parasite. L'activation conduit à la production de radicaux alkyles qui déclenchent l'apparition d'un stress oxydatif entrainant la mort du parasite.Dans ce travail, nous avons synthétisé des alcoxyamines inédites possédant des structures chimiques particulières. Ces alcoxyamines sont activables par protonation ou par complexation par des ions métalliques tels que le Fe(II) afin de produire de façon rapide et ciblée des radicaux capable d'induire un stress oxydatif. Des études cinétiques des molécules préparées dans ce manuscrit ont aussi été effectuées. Celles-ci ont montré une réduction drastique des énergies d'activation et des temps de demi-vie des alcoxyamines activées permettant de produire des radicaux rapidement et de manière sélective. Ce travail a permis d'obtenir des alcoxyamines modèles pour valider le concept d'alcoxyamines anti-paludéens. / This work presents a new application of alkoxyamines in therapeutics chemistry, in order to fight the parasite plasmodium falciparum, a parasite responsible for malaria.This idea is based on a mechanism similar to that of artemisinin, a standard drug used for malaria. Artemisinin is activated by iron(II) of heme, released during hemoglobin digestion by the parasite. Activation leads to the formation of radicals which trigger oxidative stress leading to the death of the parasite.In this work, we have synthesized new alkoxyamines with particular chemical structures. These alkoxyamines, upon protonation or metal-complexation, produce radicals able to afford oxydative stress. Moreover kinetic studies showed a drastic reduction of the activation energies and half-lives of activated alkoxyamines in oder to produce quickly radicals, which makes it possible to obtain model alkoxyamines with anti-malarial activities.
668

Some recent developments in free-radical additions to olefins and heteroarenes / Quelques Développements récents dans les additions des radicaux libres sur les oléfines et les hétérocycles aromatiques

Jatoi, Ashique Hussain 16 April 2019 (has links)
Dans le cadre de cette thèse, nous avons étudié plusieurs processus radicalaires et en particulier l'addition de radicaux libres sur des systèmes insaturés tels que les alcènes et les hétérocycles aromatiques. Nous avons ainsi montré la réactivité unique des radicaux carbamoyles, issus de la décarboxylation des acides oxamiques. La carbamoylation "sans métal" photocatalysée des hétérocycles a donc été réalisée en présence d'un réactif iodé hypervalent, conduisant à des bases hétéroaromatiques fonctionnalisées, généralement avec de bons rendements. Le processus a été étendu aux acides oxamiques préparés à partir d'acides aminés homochiraux, la réaction se déroulant sans racémisation du substrat initial.Dans la recherche d'un groupe fonctionnel équivalent à un aldéhyde et compatible avec les groupes fonctionnels résidents, nous avons mis au point un nouveau procédé de carbo-cyanation des oléfines par voie radicalaire, permettant l'incorporation, sur un squelette oléfinique, d'un fragment portant un groupe électroattracteur et un groupe cyano. Des conditions photochimiques ont également été développées afin d'éviter l'utilisation d'amorçeurs coûteux tels que le di-tert-butyl hyponitrite (DTBHN). Cette réaction clé a ensuite été utilisée afin de construire, en seulement 4 étapes, un modèle du squelette bicyclique de l’alcaloïde leuconoxine.Enfin, dans la dernière partie de la thèse, nous avons décrit une synthèse simple de naphthalénones, portant un stéréocentre quaternaire benzylique tout carboné. La réaction entre un halogénure de phénacyle et un cyclopropène substitué se déroule sous photocatalyse en utilisant un catalyseur à l'iridium et de la lumière visible. Une carbo-arylation du cyclopropène est ainsi réalisée conduisant au cyclopropane correspondant, lequel s’ouvre dans les conditions de la réaction pour conduire à la naphthalénone souhaitée avec des rendements modérés, mais avec rétention de la chiralité du cyclopropène homochiral initial. / In the context of this thesis we studied several radical processes and in particular the addition of free-radicals onto unsaturated systems such as alkenes and aromatic heterocycles. We have thus shown the unique reactivity of carbamoyl radicals, issued from the decarboxylation of oxamic acids. Photocatalyzed “metal-free” carbamoylation of heterocycles was thus performed in the presence of an hypervalent iodine reagent, leading to -functionalized heteroaromatic bases, generally in good yields. The process was extended to oxamic acids prepared from homochiral amino acids and was shown to proceed without racemization.In the search for a functional group equivalent to an aldehyde and compatible with resident functional groups, we have devised a new free-radical olefin carbo-cyanation process, allowing the incorporation, on an olefin backbone, of a fragment bearing an electron-withdrawing group and a cyano group. Photochemical conditions have also been developed in order to avoid the use of costly initiators such as the di-tert-butyl hyponitrite (DTBHN). This key reaction was then used to construct, in only 4 steps, a bicyclic skeleton model for the alkaloid leuconoxine.Finally, in the last part of the thesis, we have described a straightforward synthesis of naphthalenones, bearing an all-carbon benzylic quaternary stereocenter. The reaction between a phenacyl halide and a substituted cyclopropene proceeds under photocatalysis using an iridium catalyst and visible light. A carbo-arylation of the cyclopropene is thus carried out leading to the corresponding cyclopropane, which is opened under the reaction conditions to afford the desired naphthalenone in moderate yields, with retention of the chirality of the starting homochiral cyclopropene.
669

Re-claiming the radical: documentary and video advocacy in the age of new media

Watson, Ryan Grant 01 May 2015 (has links)
This project interrogates the status of documentary film as an oppositional force and conduit for radical social and political change. The first two chapters examine the interconnected transnational history of the radical or "committed" documentary. This historical inquiry leads me to construct a set of parameters for how the radical documentary was defined and codified between 1926 and 1990. My investigation is particularly attuned to how documentary filmmakers in this tradition moved away from a didactic mode of address that sought to educate a state sanctioned "citizen subject." Instead, I argue that the radical documentary tradition grew out of the modernist avant-garde movement and activated a "revolutionary subject" in opposition to the state. To date, there have only been a handful of accounts locating post-1990s documentary practices within the domain of radical political concerns and the possibilities presented by the intersection of documentary and new media technology. The second part of the dissertation examines how such practices extend and challenge the aforementioned historical definitions while intervening in a diverse range of contexts. The final three chapters focus on an eclectic corpus of films and videos that include the work of the video advocacy organizations WITNESS and B'Tselem, student documentaries made in Iraq, and interactive documentary projects by new media artists Zohar Kfir and Sharon Daniel. I argue that these groups and artists create an "activist subject" that intervenes within specific social and political situations during wars, occupations, and cases of human rights abuses. Ultimately, I conclude that the radical power of documentary film lies not in and of itself as singular object of art or evidence, but in the discourses it engenders and within the discourses and contexts in which it is placed. In the increasingly post-digital age of new media, the study and practice of radical documentary demands a multi-faceted approach as well as an openness to expanding definitional boundaries of what a documentary is, how it functions, how it circulates, and how its impact is measured.
670

Inhibition of peroxide removal systems and ascorbate-induced cytotoxicity in pancreatic cancer

Van Beek, Hannah 01 May 2016 (has links)
Compared to normal cells, cancer cells tend to have higher concentrations of reactive oxygen species (ROS) such as hydrogen peroxide (H2O2) due to an accelerated cellular metabolism. The high ROS content leaves cancer cells increasingly susceptible to oxidative stress-induced cell death. This susceptibility can be manipulated in selective cancer therapy by further increasing production of ROS or inhibiting peroxide removal systems or a combination of the two. Pharmacological ascorbate (high-dose intravenous ascorbate) has been shown to sensitize pancreatic cancer to ionizing radiation (IR) by increasing production of ROS such as H2O2. Glutathione reductase (GR) and thioredoxin reductase (TrxR) are both important enzymes in peroxide removal systems. GR and TrxR function to recycle key electron donors in the cellular removal of H2O2. We hypothesized that inhibiting the peroxide removal systems via inhibition of GR and TrxR would enhance ascorbate-induced cytotoxicity in pancreatic cancer cells. Inhibition of TrxR activity enhanced ascorbate-induced cytotoxicity in MIA PaCa-2 pancreatic cancer cells. Additionally, knockdown of GR protein expression in combination with pharmacological ascorbate treatment increased MIA PaCa-2 pancreatic cancer cell sensitivity to IR. In MIA PaCa-2 and 403 F1 patient-derived pancreatic cancer cells, inhibition of both TrxR and GR activity combined with pharmacological ascorbate enhanced radiosensitivity. However, this effect was not seen in 339 patient-derived pancreatic cancer cells treated with the same dose of ascorbate. In conclusion, inhibition of TrxR activity, GR activity, or both enhances radiosensitivity and ascorbate-induced cytotoxicity in some, but not all, pancreatic cancer cell lines. Treatments combining ascorbate with inhibition of H2O2 removal may be an effective strategy for treatment of pancreatic adenocarcinoma.

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