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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.
41

Der Landvermesser : Hanns-Josef Ortheils Suche nach der poetischen Heimat

Schmitz, Helmut January 1996 (has links)
No description available.
42

Social values in some novels of the 'Heimatkunst' movement

Watts, Donald January 1975 (has links)
The thesis compares the values and attitudes promoted in the fiction of five authors associated with the 'Heimatkunst' movement. The introduction attempts a definition of the term 'Heimatkunst' and then proceeds to an examination of the theoretical writings of Adolf Bartels and Friedrich Lienhard, indicating the often considerable differences in attitude between the two critics and outlining such common ground as they share with each other and the "practitioners of the movement treated in this study. The thesis then moves to an analysis of single novels, where necessary relating these works to their authors' other writings. The novels chosen for analysis are Wilhelm von Polenz' Der Büttnerbauer, Adolf Bartels' Die Dithmarscher, Gustav Frenssen's Jörn Uhl, Ludwig Ganghofer's Der hohe Schein and Hermann Löns's Der Wehrwolf. These analyses confirm the existence of that common ground between the authors outlined in the introduction - their veneration of rural life and their suspicion of urban culture and values, their anti- intellectual bias, nationalist or racialist sympathies and their belief that contemporary ills may be cured or ameliorated by a return to the pre-industrial, nature-based values of the rural community. The manner, degree and consistency with which they commit themselves to these attitudes and views vary and there are certain preoccupations common to only some of the authors dealt with, although even these differing concerns can often be related to individual interpretations of shared premises. The thesis concludes with an examination of common stylistic and technical features of their fiction and the literary devices employed to direct the reader's sympathies.
43

Selection and optimization of the seeding procedure prior to the synthesis of Pd-based membranes

Mc Donald, Earl January 2014 (has links)
Magister Philosophiae - MPhil / Pd based membranes are known for their incredible selectivity towards H2. In order for Pd membranes to display high H2 selectivity, a defect free layer of Pd needs to be deposited onto a support. Although various fabrication techniques do exist, many researchers have attempted to produce defect free Pd-based films, using electroless plating. The first step in the preparation technique involves “seeding” of the support structure. Even though these seeds, if well distributed and anchored to the support, are crucial in order to obtain the defect free Pd layer, they hardly ever received attention from the science community. This thesis reports findings on various seeding methods as well as the resulting microstructures of the Pd films formed as a result of the type of seeding method employed. Finally the quality of the membranes using the most promising seeding technique was determined by subjecting the membranes to permeance tests with N2 at both high and low temperatures as well as with H2 at high temperatures.
44

Vocalisations evidence from Germanic

Taylor-Raebel, Gary January 2017 (has links)
A vocalisation may be described as a historical linguistic change where a sound which is formerly consonantal within a language becomes pronounced as a vowel. Although vocalisations have occurred sporadically in many languages they are particularly prevalent in the history of Germanic languages and have affected sounds from all places of articulation. This study will address two main questions. The first is why vocalisations happen so regularly in Germanic languages in comparison with other language families. The second is what exactly happens in the vocalisation process. For the first question there will be a discussion of the concept of ‘drift’ where related languages undergo similar changes independently and this will therefore describe the features of the earliest Germanic languages which have been the basis for later changes. The second question will include a comprehensive presentation of vocalisations which have occurred in Germanic languages with a description of underlying features in each of the sounds which have vocalised. When considering phonological changes a degree of phonetic information must necessarily be included which may be irrelevant synchronically, but forms the basis of the change diachronically. A phonological representation of vocalisations must therefore address how best to display the phonological information whilst allowing for the inclusion of relevant diachronic phonetic information. Vocalisations involve a small articulatory change, but using a model which describes vowels and consonants with separate terminology would conceal the subtleness of change in a vocalisation. The model presented here has therefore been designed to unite the descriptions of consonants and vowels to better demonstrate this change whilst allowing for relevant phonetic information to be included.
45

Investigação das propriedades citotóxicas e imunológicas de complexos de paládio(II) in vitro utilizando o modelo experimental de Ehrlich

Rocha, Michelle Corrêa da [UNESP] 05 June 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-06-05Bitstream added on 2014-06-13T19:13:53Z : No. of bitstreams: 1 rocha_mc_me_arafcf.pdf: 757379 bytes, checksum: f386cabb4d38b8f9552bfba42f8b50aa (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Universidade Estadual Paulista (UNESP) / O câncer destaca-se pela alta incidência e mortalidade. O tratamento do câncer compreende cada vez mais a quimioterapia combinada, ou seja, substâncias antitumorais agindo conjuntamente com as células do sistema imune, potencializando-as ou apenas mantendo-as viáveis para exercerem sua função. Dentre os tipos celulares que constituem o sistema imunológico, os macrófagos são apontados como os principais elementos do organismo de combate aos tumores. Os macrófagos ativados agem liberando produtos tais como radicais de oxigênio (H2O2) e nitrogênio (NO), interleucina-1ß (IL-1ß) e fator de necrose tumoral (TNF-a), que são prejudiciais às células tumorais dependendo da concentração, além de sua ação indireta através da secreção de interferon-gama (IFN-.). Complexos de paládio(II) são investigados há décadas, destacando-se por sua potencialidade como agente antitumoral. Neste trabalho avaliou-se a ação dos compostos [Pd(dmba)(X)(dppp)] (X= SCN, NCO, N3 ou Cl) sobre as células tumorais de Ehrlich e macrófagos in vitro, utilizando como padrão a cis-platina (cis-Pt). Para tanto, foram realizados ensaios para determinação do índice de citotoxicidade mediano, o IC50, para cada composto pelos períodos de 24 e 48h e com base em tais concentrações investigadas para os macrófagos verificou-se a produção e/ou inibição de NO e H2O2, além das citocinas TNF-a, IFN-. e IL-1 bem como a atividade citotóxica/citolítica. Os compostos demonstraram ser agentes promissores por seus efeitos sobre as células tumorais e imunes, muitas vezes de forma igual ou superior à cis-Pt, droga de uso corrente na quimioterapia do câncer. / The cancer is a disease with high incidence and mortality. The cancer treatment involves the combinated chemotherapy wich one involves antitumour substances acting along with the immune cells, stimulating or only keeping them able to act in the immune response. Between the cell types that belong to the immunological system, the macrophages are considered the main elements of the body that can act against tumours. The activated macrophages act releasing substances like oxygen (H2O2) and nitrogen (NO) radicals, interleukin-1 (IL-1) and tumour necrosis factor alpha (TNF-á), wich are not beneficial to the tumour cells in some concentrations, besides its indirect action towards interferon-gama (IFN-ã) release. Palladium(II) complexes are employed in many studies to verify its antitumour properties. For example we can describe the four following compounds: [Pd(dmba)(X)(dppp)], X= SCN, NCO, N3 or Cl. This work had as goal the evaluation of the action of such compounds towards Ehrlich tumour cells, macrophages and lymphocytes in vitro, employing cis-platin (cis-Pt) as standard. The following parameters were evaluated: the cytotoxic index (IC50) of each compound after 24 and 48h incubation for Ehrlich tumour cells, macrophages and lymphocytes; the immunological behaviour of the compounds in the concentrations previously determined such as NO and H2O2 production or inhibition, besides the cytokines TNF-á, IFN-ã and IL-1 as well as the cytotoxic/cytolitic activity. The compounds presented a good behaviour, based on their efects towads tumour and immune cells, many times like or even better than cis-Pt, standard drug in cancer chemotherapy.
46

Préparation et caractérisation de catalyseurs bimétalliques Re-Pd/TiO2 pour l'hydrogénation de l'acide succinique issu de la biomasse / Preparation and characterization of Re-Pd/TiO2 bimetallic catalysts for the hydrogenation of succinic acid from biomass

Tapin, Benoît 29 November 2012 (has links)
L'objectif de ce travail est de mettre au point des catalyseurs bimétalliques Re-Pd/TiO2 actifs et suffisamment robustes en milieu hydrothermal pour hydrogéner sélectivement l'acide succinique (SUC) en 1,4-butanediol (BDO). Dans un premier temps, des catalyseurs monométalliques 2%Pd/TiO2 sont préparés et caractérisés par diverses techniques physico-chimiques. Les résultats montrent l'importance d'un certain nombre de paramètres sur les propriétés des catalyseurs et leurs performances catalytiques. Les catalyseurs à base de palladium sont très sélectifs en γ-butyrolactone mais très peu en BDO. Différentes teneurs en rhénium sont ensuite déposées sur les catalyseurs 2%Pd/TiO2 (par imprégnation successive (IS) et par réduction catalytique (RC)). L'existence d'une interaction entre les deux métaux Pd-Re est mise en évidence par plusieurs techniques de caractérisation (chimisorption H2, réaction modèle de déshydrogénation du cyclohexane, RTP, XPS, MET-EDX). L'ajout de rhénium permet d'augmenter la vitesse de la réaction de transformation du SUC et améliore la sélectivité en BDO. Pour les catalyseurs préparés par IS, des quantités importantes de rhénium (3-4%) sont nécessaires pour avoir un effet optimum, alors que le dépôt par la méthode RC doit être limité à des teneurs plus faibles (< 1%). Néanmoins, les catalyseurs préparés par IS conduisent à une meilleure activité et sélectivité en BDO. / The objective of this work is to synthesize bimetallic catalysts Re-Pd/TiO2 active and strong enough in hydrothermal environment to hydrogenate selectively the succinic acid (SUC) to 1,4-butanediol (BDO). At first, monometallic 2%Pd/TiO2 catalysts are prepared and characterized by various physico-chemical methods. The results show the importance of several parameters on the catalyst properties and catalytic performances. Palladium catalysts are very selective to γ-butyrolactone but few to BDO. Various rhenium contents are then deposited on 2%Pd/TiO2 catalysts (by successive impregnation (SI) and catalytic reduction (CR)). The existence of an interaction between both Pd-Re metals is revealed using several techniques of characterization (H2 chemisorption, model reaction of cyclohexane dehydrogenation, TPR, XPS, TEM-EDX). Adding rhenium both allows enhancing the reaction rate of SUC transformation and improving the selectivity to BDO. For catalysts prepared by SI, important quantities of rhenium (3-4%) are needed for optimal effect, while the deposit must be limited to lower contents (< 1%) when using the CR method. Nevertheless, catalysts prepared by SI lead to better activity and selectivity to BDO.
47

Palladium-Based Catalysts for Ethanol Electrooxidation in Alkaline Media

Brazeau, Nicolas January 2015 (has links)
Direct ethanol fuel cells have been shown to be a good alternative to internal combustion engines in order to reduce the CO2 emissions. In this study, Pd and Pd-based nanocatalysts were deposited on various supports (carbon black, graphene, SnO2, CeO2, TiO2, TiO2 nanotubes and SnO2/TiO2 nanotubes) and their effects on the catalytic properties of the deposited metal for ethanol oxidation in alkaline media are studied. These modifications to the catalytic systems have shown to cause an increase in the reaction rate at the surface of the catalyst and to reduce the overpotential of the ethanol oxidation reaction. Two different promotion mechanisms have been identified. Firstly, the supply of OH- ions at the metal-support interface facilitates the oxidation of adsorbed molecules on neighbouring Pd sites. Secondly, an increase in electron density of Pd nanoparticles with increasing support reducibility modifies the adsorption strength of ethanol and its oxidation intermediates.
48

Progress versus Pseudoprogress beim Lungenkarzinom unter Immuntherapie / Progress versus pseudoprogress in lung cancer under immunotherapy

Schiwitza, Annett Jenny 31 December 1100 (has links)
No description available.
49

The effect of functional electrical stimulation on akinetic gait in patients with Parkinson's disease

Uys, Nicole Ashleigh 02 June 2009 (has links)
Impaired gait and postural instability in patients living with Parkinson’s disease (PD) are regarded as the main aspects of the disease that causes disability in their home and work environment. As a progressive neurological movement disorder due to degeneration in the basal ganglia, PD is the second most common neurological disease after stroke and the fourth most common neuro-degenerative disease in the elderly. Functional Electrical Sensory Stimulation (FESS) (Group 1) and Functional Electrical Sensory and Motor Stimulation (FES&MS) (Group 2) was administered to the common peroneal nerve as external cues to facilitate the initiation of taking a step in patients with akinesia. The hypotheses that were tested were: Hypothesis 1 (H1) FESS and FES&MS decrease freezing/akinesia and bradykinesia/hypokinesia during gait in patients suffering from PD. Null Hypothesis (H0) FESS and FES&MS do not decrease freezing/akinesia and bradykinesia/hypokinesia during gait in patients suffering from PD. Hypothesis 2 (H2) FESS and FES&MS decrease freezing/akinesia and bradykinesia/hypokinesia during gait in patients suffering from PD to such an extent that it improves the quality of life of patients. Null Hypothesis 2 (H02) FESS and FES&MS do not decrease freezing/akinesia and bradykinesia/hypokinesia during gait in patients suffering from PD to such an extent that it improves the quality of life of the patients. Hypothesis 3 (H3) FESS decreases freezing/akinesia and bradykinesia/hypokinesia during gait in patients suffering from PD more than FES&MS. Null Hypothesis 3 (H03) FESS does not decrease freezing/akinesia and bradykinesia/hypokinesia during gait in patients suffering from PD more than FES&MS. A single blind, randomized active controlled clinical trial was conducted. Patients with PD who experienced freezing/akinesia and bradykinesia / hypokinesia and met the inclusion and exclusion criteria of the study were allocated randomly into two groups. Ten (10) patients were randomly allocated to each group. The baseline measurement was determined by calculating the average of the measurements at week zero (0) and week two (2). Results of the participants in each group at week fourteen (14) (after twelve (12) weeks of FESS and FES&MS respectively) were compared to their baseline measurement, as well as between Group 1 and Group 2. The FESS and FES&MS was removed at week fourteen (14) and measurements were repeated at week twenty four (24). Parameters of gait that were used in the trial included; the time, speed, number of steps, average step length, Freezing of gait scale and PCI to complete a walking task. The Qol was determined by using the PDQ-39 and the motor part of the UPDRS. From the results obtained the alternative hypotheses H1, H2 and H3 was accepted for Group 1. The null hypothesis H0 and the alternative hypothesis H3 was accepted for Group 2 It can be concluded from the results of this clinical trial that FESS decreases akinetic episodes in patients with PD statistically significantly and clinically improves their Qol. Qol was statistically significantly improved in Group 2 although hypothesis H1 was not accepted for Group 2. / Dissertation (MPhysT)--University of Pretoria, 2009. / Physiotherapy / unrestricted
50

Etude des homologies phénotypiques et fonctionnelles des lymphocytes B en latence III de l'EBV avec les cellules B régulatrices, implication de l'axe PD-1/PD-L1 / Study of phenotypic and functional homologies of EBV latency III B-lymphocytes with regulatory B cells, involvement of the PD-1 / PD-L1 axis

Auclair, Héloïse 06 October 2017 (has links)
Le virus d’Epstein-Barr (EBV) est le premier virus transformant à avoir été identifié chez l’Homme. Il infecte plus de 90% de la population adulte mondiale, persistant sous forme épisomale dans le compartiment B mémoire tout au long de la vie de l’hôte. Lors de la primo-infection et lors de phases de réactivation du virus, les cellules B immortalisées sont en programme de latence III, aussi appelée phase de prolifération, où l’ensemble des protéines de latence sont exprimées. Lorsque les hôtes sont immunocompétents, un équilibre entre hôte et virus s’établit et la plupart des cellules B infectées sont éliminées par le système immunitaire de l’hôte, principalement par les lymphocytes T cytotoxiques. En cas de déficit immunitaire, il peut y avoir émergence de lymphomes, tels que les désordres lymphoprolifératifs des patients immunodéprimés (PTLDs), les lymphomes non-Hodgkiniens (LNH) et Hodgkiniens (LH). Les travaux antérieurs du laboratoire ont permis de révéler que l’immuno-inhibiteur PD-L1/B7-H1/CD274 est surexprimé à la surface des lymphocytes B en latence III de l’EBV. L’interleukine-10 (IL-10) est également sécrétée par ces cellules. Ces caractéristiques sont communes aux cellules B régulatrices (Bregs). Le but de ma thèse était d’interroger les caractéristiques immuno-modulatrices des cellules B en latence III de l’EBV, dans le cadre des propriétés des Bregs. Nous montrons que les cellules B en latence III de l’EBV possèdent les déterminants antigéniques communs aux Bregs immatures (CD24High CD38High PD-L1High), associée à une surexpression des cytokines immunosuppressives cardinales des Bregs (IL-10, TGF-β1 et IL-35). Nous montrons que les cellules B en latence III de l’EBV peuvent conduire à la mort des cellules T CD4 autologues, ainsi qu’à l’inhibition de la prolifération des lymphocytes T CD4 et CD8, au profit de l’expansion de lymphocytes T régulateurs (Tregs). Nous avons trouvé que cette expansion est médiée par l’axe PD-1/PD-L1. Ces travaux mettent en évidence un nouveau mécanisme de l’EBV concernant le détournement du système immunitaire de l’hôte, augmentant ses capacités oncogéniques. / The Epstein-Barr virus (EBV) is the first transforming virus discovered in humans. It infects more than 90% of the global adult population, persisting in an episomal form in the memory B-cell compartment throughout the life of the host. During primo-infection and during phases of viral reactivation, immortalized B-cells are in latency III, also called the proliferation program, in which the full range of latency proteins are expressed. In immunocompetent subjects, a balance between virus and host is established, and most infected B-cells are eliminated by the host’s immune system, mainly by cytotoxic T lymphocytes. Deficit of the immune system may lead to lymphomagenesis, such as post-transplantation lymphoproliferative disorders (PTLDs), non-Hodgkin’s (NHL) or Hodgkin’s lymphomas (HL). Previous studies in the lab revealed that the immuno-inhibitor PD-L1/B7-H1/CD274 was overexpressed on the surface of EBV latency III B-cells. Interleukin-10 (IL-10was also secreted by these cells. These features are shared with regulatory B-cells (Bregs). Our objective was to examine the immunomodulatory features of EBV latency III B-cells, in the frame of Bregproperties. We found that EBV latency III B-cells possessed the antigenic determinants common to immature Bregs (CD24High CD38High PD-L1High), associated with overexpression of Breg immunosuppressive cytokines (IL-10, TGF-β1 and IL-35). EBV latency III B-cells led to death of autologous CD4 T-cells, as well as inhibition of CD4 and CD8 T-lymphocyte proliferation, favoring regulatory T-cell (Treg) expansion. We found that this expansion was mediated by the PD-1/PD-L1 axis. This study highlights a new mechanism of EBV for t diversion of the host immune system thereby increasing its oncogenic properties.

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