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Multi-metallic aerogels have emerged as a promising unsupported, high surface area-based metal material for different applications in heterogeneous catalysis and electrochemistry. The fabrication of these multi-metallic aerogels is based on a complex gelation process which is characterized by controlled aggregation of metallic nanoparticles to form a macroscopic network structure in aqueous solution. However, achieving structural homogeneity of the multi-metallic aerogels in terms of diameter of the nanochains and chemical composition at the nano- as well as at the macro-scale is still a great challenge. In this paper, we show the characterization of two Pd-Pt aerogels prepared by the two-step gelation method. The structural homogeneity and chemical distribution of both metals (Pd and Pt) inside the aerogels were analyzed using high-resolution (scanning) transmission microscopy (HR(S)TEM), energy-dispersive X-ray spectroscopy (EDX), extended X-ray absorption fine structure (EXAFS) spectroscopy, and cyclic voltammetry. Based on the microscopic and spectroscopic results, the Pd-Pt aerogels show the presence of Pd/Pt-rich domains inside the long-range framework. It is evident that the initial monometallic features dominate over alloying during the gelation process. Although the same synthetic approach for Pd-Pt aerogels with different atomic ratios was used, we observed that the sizes of these monometallic domains strongly varied between the Pd-rich and Pt-rich aerogels. For instance, the Pd-rich aerogels showed larger clusters with a size range from few nanometers up to several tens of nanometers, while the dimension of the clusters of the Pt-rich aerogels varies from the sub-nanometers to a few nanometers. The presence of the metal clusters strongly influenced the electrochemical robustness of these Pd-Pt aerogels. Electrochemical durability investigations revealed that the aerogels with a high content of Pd are less stable due to the gradual dissolution of the less noble metal in particular inside the Pd-rich domains. A better chemical and structural homogeneity might improve the life-time of the Pd-Pt aerogels under electrochemical conditions. In this work, we provide a better understanding about the structure and chemical distribution of the bimetallic aerogel framework prepared by the two step gelation process.

The aim of this study is to analyse the discourse surrounding the preservation of the Icelandic language in light of the growing immigrant population in Iceland. This is done by analysing and comparing two public language policies through the lens of Critical Discourse Analysis, more specifically Discourse Historical Approach. This thesis contributes to the academic research on the Icelandic language and its immigrant population by offering a comparative study of a previously unexplored research topic. The findings indicate that there has been a discursive shift from conservative to more progressive attitudes towards the preservation of the Icelandic language, and the connection between language preservation and purification is beginning to weaken. The study shows that immigrants’ role as language users and language preservers is not sufficiently addressed or met, and a more inclusive approach towards the language is needed to facilitate the prosperous growth of a multicultural society and immigrants’ sense of belonging.

This thesis strives to understand the underlying narrative behind the current distribution of the public funding between the writers of the Spanish language and writers of native languages in Mexico, as well as contextualise the policies of the Mexican State that often materialise colonial dynamics. The situation of native women writers is emphasised as they are forced to tackle multiple disadvantages based on unjust social structures. At the same time, the concept of national and world literary canon plays an exclusionary role when it comes to inclusion of diverse literary oeuvres that represent different versions of the world as the one traditionally carried by European languages and their literary works.

La thérapie de resynchronisation cardiaque (CRT) est un traitement qui diminue la mortalité et améliore la qualité de vie des patients atteints d’insuffisance cardiaque et présentant un dyssynchronisme de la contraction ventriculaire gauche. Malgré le succès de cette thérapie, plus de 30% des patients ne présentent pas l’amélioration désirée. Plusieurs études portant sur le synchronisme électrique ou mécanique de la contraction ont été effectuées mais peu d’entres elles se sont attardées sur le couplage électromécanique à l'échelle macroscopique. Ce projet a comme objectif d’observer le comportement électromécanique des ventricules canins en présence d’un resynchronisateur cardiaque. Un logiciel a été développé pour permettre l’analyse des informations provenant de la cartographie endocardique sans contact et de la ventriculographie isotopique tomographique chez 12 sujets canins insuffisants. Pour observer la réponse mécanique suite à l’activation électrique, nous avons premièrement recalé les surfaces issues des 2 modalités. Ensuite, nous avons défini les limites du cycle cardiaque, analysé les signaux électriques et les courbes de déplacement de la paroi endocardique. Le début de la contraction est défini par un déplacement radial de 10% vers le centre du ventricule. Les résultats démontrent que la durée d’activation du ventricule gauche et la largeur du QRS augmentent en présence d’une stimulation externe et que les délais électromécaniques sont indépendants dans les modes de stimulation étudiés (sinusal, LVbasal, RVapex ou BIV) avec une moyenne de 84,56±7,19 ms. Finalement, nous avons noté que la stimulation basolatérale procure une fonction cardiaque optimale malgré une durée prolongée du QRS. / Cardiac Resynchronization Therapy (CRT) is known to decrease mortality rate and improve the quality of life for patients suffering from heart failure with left ventricular contraction dyssynchrony. However, it has been shown that 30% of patients do not respond to this therapy. Many studies have investigated the electrical or mechanical synchronism of contraction but few have studied the activation contraction coupling on a macroscopic level. The objective of this study is to observe the left ventricle’s electromechanical behaviour under biventricular stimulation. A software has been developed to analyse the data coming from non-contact mapping and blood pool SPECT for 12 dogs with heart failure. In order to observe the mechanical response following an electrical activation, we have registered 3D surfaces generated by the 2 modalities. Afterward, we defined the cardiac cycle limits, and we analyzed electrical signals as well as endocardial wall displacement curves where the onset of contraction was defined as a 10% inward radial displacement. Results show that both duration of left ventricular activation and QRS increase with pacing and that electromechanical delays are independent of stimulation mode (mean value 84,56 ± 7,19 ms). Finally, we observed that basolateral stimulation shows the best improvement for left ventricular function while presenting a long QRS duration.

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<p>In this thesis we study several inverse sampling procedures to test for homogeneity in a multivariate hypergeometric distribution. The procedures are finite population analogues of the procedures introduced in Panchapakesan et al. (1998) for the multinomial distribution. In order to develop some exact calculations for critical values not considered in Panchapakesan et al. we introduce some terminologies for target probabilities, transfer probabilities, potential target points, right intersection, and left union. Under the null and the alternative hypotheses, we give theorems to calculate the target and transfer probabilities, we then use these results to develop exact calculations for the critical values and powers of one of the procedures. We also propose a new approximate calculation. In order to speed up some of the calculations, we propose several fast algorithms for multiple summation.</p> <p>N >= 1680000, all the results are the same as those in the multinomial distribution.</p> <p>The computing results showed that the simulations agree closely with the exact results. For small population sizes the critical values and powers of the procedures are different from the corresponding multinomial procedures, but when</p> / Master of Science (MSc)

近幾年，台灣雖然有線頻道的開放，新聞媒體如雨後春筍冒出，但並無走向自由主義所奉行的「獨佔產生一致、競爭造成多元」的局面，反而造就新聞內容高度同質化、貧乏化與劣質化，基層新聞從業人員聲譽也每況愈下，飽受雙重壓力，外有各界針貶責難、內臨組織管理階層的不公平待遇。 許多研究將上述現象，歸咎於媒體結構（前端）的畸形，或從產製結果（後端）-內容面，剖析新聞場域的種種亂象。而本研究立旨於解構一窩蜂新聞產製現象中的來龍去脈、運作過程與利弊得失，故採不同於以往的分析取徑，以「電視新聞產製過程」（中端）中的行動者為主角，透過田野觀察、深度訪談取得研究資料，瞭解電視新聞從業人員與同業、電視新聞組織主管的互動關係，最後將田野資料進行紮根演繹，具體化研究目標與研究主題，瞭解電視新聞生產結構，並建立「一窩蜂新聞產製流程模式」。 本研究以「一窩蜂新聞學」（Pack Journalism）為根基，並以以「記者一窩蜂動作」為經，「與同業（同事）、決策者的互動關係」為緯，並援引Bourdieu新聞場域理論與Giddens的結構行動論，解析造成一窩蜂新聞產製與新聞同質化的內（記者個人心理）、外（新聞結構）在因素。 研究發現將一窩蜂新聞產製的成因分為五點，包括傳播者個人層次、常規層次、跨新聞組織層次、媒體外層次與社會文化層次。而本研究也發現新聞場域形成一迴路機制，藉由互相鏡射下，產生出速度政權與收視率的禁錮，在在都成為記者一窩蜂產製新聞的生存心態，導致新聞內容趨向高度同質化。不過，為了在場域的鬥爭中取得優勢地位，記者會藉由「秀異展示」，凸顯自己，轉化為具體目標，就是追求「獨家新聞」與建立「領導品牌」，在不知不覺中增強「象徵暴力」的施展能量，使記者本身陷入更深的束縛。 那新聞從業人員有抵抗的可能性嗎？本研究也發現新聞結構必須經過整頓，才有抵抗的空間，但在空間來臨之前，記者可以先行累積迂迴抵抗的資源，等待結構重整後才能一舉衝破牢網。 / In recent years, although Taiwan’s Government has allowed cable television stations to open and news media have expanded quickly, the development of television media deviates from the Liberalists’ ideal: monopoly leads to consistence, competition forms diversity. On the contrary, not only does Taiwan’s news content tend toward homogeneity and mediocrity, but also the status of journalists has gone from bad to worse. Journalists face two sets of pressures: there have been acute criticisms from Taiwanese society, and working conditions have deteriorated badly. Many research papers have dissected the above phenomenon in the news field, from the abnormality of media structure to the content of news production. This study aims to analyze the development, the operation, the merits and demerits of pack journalism, and therefore adopts a different approach from past analysis. In order to study pack journalism, this study adopts Bourdieu’s journalistic field theory and Giddens’ structure / activities theory to analyze news production processes. It focuses on journalists themselves and attempts to understand the interactive relationship of TV news workers, colleagues and managers though field study and in-depth interviews. Finally, I use grounded theory to analyze field information, concretizing the research subject and goals, with discussions of the model of news production in pack journalism. This study claims that there are five aspects of news production processes when studying pack journalism: individual level, media routines level, cross-news organization level, extra-media level and social-cultural level. The news field gives rise to a system marked by operational closure, which contributes to speed-driven news production and response to television ratings. These become the primary motives for journalists’ news generation, and result in homogeneity of news content. However, in order to advance in their field, journalists will try to distinguish themselves by pursuing scoops and branding themselves as leaders. Unconsciously, they reinforce the power of symbolic violence and get themselves into more complicated positions. Can news workers resist these scrapes? Can news workers resist these scrapes? Journalist need to accumulate resources to resist in the first place. With the efforts, the media structure is going to reorganized and then the journalists will have more space to stand firm the pressures of being homogeneity. After these changes take place, journalists may just be able to break through the shackles of pack journalism.

L'évaluation de l'asynchronisme mécanique ventriculaire sous stress a soulevé une attention importante en tant que facteur prédictif de la réponse au traitement de resynchronisation cardiaque (CRT). De plus, il semble exister une relation significative entre le devenir du patient et la présence d’asynchronisme au repos. Plusieurs méthodes échocardiographiques peuvent être utilisées pour évaluer l’asynchronisme. Cependant, parmi toutes les différentes méthodologies ou index existant dans ce domaine, aucun critère ne fait l’unanimité. Cette thèse étudie l'importance des techniques d'imagerie nucléaire dans le cadre de l’évaluation de l’asynchronisme cardiaque induit par le stress en utilisant trois différents modèles canins expérimentaux. Le premier chapitre vise à examiner les effets du stress sur le synchronisme de la contraction du ventricule gauche (VG) en utilisant l'imagerie synchronisée de perfusion myocardique dans une cohorte canine normale. Le stress a été induit par différents niveaux d’infusion de dobutamine sur six sujets sains. Les paramètres hémodynamiques et l’asynchronisme ont été évalués par des mesures de pressions ventriculaires. L'analyse de phase sur l’imagerie s’est effectuée en utilisant un logiciel commercialement disponible (QGS) et un logiciel interne (MHI4MPI), basée sur le déplacement et l’épaississement des parois ventriculaires. L’augmentation de la concentration de dobutamine a démontré une amélioration de la capacité fonctionnelle et une réduction de l’asynchronisme ventriculaire. L’analyse de l’asynchronisme calculée à partir de l’épaississement de la paroi semble plus robuste et plus sensible que l’utilisation du déplacement des parois. (Salimian et. al., J Nucl Cardiol., 2014) Le second chapitre étudie les différents paramètres d’asynchronisme au repos et à différents niveaux de stress dans un modèle de cardiomyopathie dilatée et à QRS étroit. Ce modèle a été créé sur dix chiens par tachycardie via stimulation de l'apex du ventricule droit pendant 3-4 semaines, permettant d’atteindre une fraction d'éjection cible de 35% ou moins. Le stress a ensuite été induit par une perfusion de dobutamine jusqu'à un maximum de 20 μg/kg/min. Les données hémodynamiques et l’asynchronisme ont été analysés par des mesures de pression ventriculaire et l’analyse de l’imagerie dynamique du compartiment sanguin. L’importante variabilité individuelle des sujets inclus dans notre cohorte empêche toute conclusion définitive sur la mesure de l’asynchronisme interventriculaire. Cependant, les différents niveaux de stress, même dans des intervalles rapprochés, ont démontré un effet significatif sur les paramètres hémodynamiques et l’asynchronisme. (Salimian et. al., J Nucl Cardiol., 2015) La troisième section vise à déterminer si l’estimation du mode de stimulation optimal effectuée au repos demeure le choix optimal lorsque le niveau d’activité cardiaque s’intensifie pour des sujets avec bloc auriculo-ventriculaire (AV) et fonction ventriculaire normale. Cinq chiens ont été soumis à une ablation du nœud AV et des sondes de stimulation ont été insérées dans l'oreillette droite pour la détection, l’apex du ventricule droit (VD) et une veine postérolatérale du VG pour la stimulation. Cinq modes de stimulation ont été utilisés : LV pur, biventriculaire (BiV) avec pré-activation de 20 ms du LV (LVRV20), BiV pur, BiV avec pré-activation de 20 ms du VD (RVLV20), VD pur. Des niveaux jusqu’à 20 μg/kg/min de dobutamine ont été atteints. Le stress a modifié l’étendue de l’asynchronisme de base et ce, pour tous les modes de stimulation. De plus, les effets physiologiques intrinsèques du stress permettent une évaluation plus précise de l’asynchronisme ventriculaire, diminuant la variabilité inter-sujet. Le mode de stimulation LVRV20 semble le mode optimal dans ce modèle, supportant l’utilisation de la stimulation bi-ventriculaire. / Assessment of ventricular mechanical dyssynchrony (MD) under stress has attracted a large amount of attention as a stronger predictor of response to cardiac resynchronization therapy (CRT) and as a parameter whose variation bears a greater relationship to clinical outcomes than resting-MD either in CRT candidates or another subset of patients. Several echocardiographic methods can be used to assess stress-MD. However, no standardized approach is currently used to explore stress-induced variations in inter- and intraventricular MD. This dissertation studies the importance of nuclear imaging techniques in assessing stress-induced MD variations by providing three different experimental canine models. The first chapter sought to examine the impacts of stress on the left ventricular (LV) synchrony with phase analysis of gated SPECT myocardial perfusion imaging (GMPS) within a normal canine cohort. Stress was induced by different levels of dobutamine infusion in six healthy subjects. Hemodynamic and LV MD parameters were assessed by LV pressure measurements and phase analysis of GMPS using commercially available QGS software and in-house MHI4MPI software with thickening- and displacement-based methodology. The increase of dobutamine level was shown to be in accordance with the improvement of LV functional capacity and reduction of MD parameters. MD analysis based on wall thickening was more robust and sensitive than the global wall displacement. (Salimian et. al., J Nucl Cardiol., 2014) The second chapter investigated the range of difference in inter- and intraventricular MD parameters from rest to various levels of stress in a dilated cardiomyopathy (DCM) and narrow QRS complex model. Ten large dogs were submitted to tachycardia-induced DCM by pacing the right ventricular apex for 3-4 weeks to reach a target ejection fraction of 35% or less. Stress was then induced by infusion of dobutamine up to a maximum of 20 μg/kg/min. Hemodynamic and MD data were analyzed by LV pressure measurements and gated-blood pool SPECT (GBPS) imaging. Individual differences in the magnitude and pattern of change in the various levels of stress precluded any definitive conclusion about interventricular MD. However, different levels of stress, even in close intervals, showed a significant positive impact on hemodynamic and intraventricular MD parameters. (Salimian et. al., J Nucl Cardiol., 2015) The third chapter sought to examine if the optimal pacing mode at rest could be the best one during the maximum stress level in terms of MD parameters in subjects with an atrioventricular (AV) block and normal function. Five dogs were submitted to AV node ablation and pacing leads were placed in the right atrium for sensing, in right ventricular (RV) apex, and in posterolateral LV vein for pacing in five modes of LV, biventricular (BiV) with 20 ms of LV pre-activation (LVRV20), BiV, BiV with 20 ms of RV pre-activation (RVLV20) and RV pacing. Stress was induced by dobutamine infusion up to a maximum of 20 μg/kg/min. Data analyses were the same as chapter one. Dobutamine stress changed the extent of resting-LV MD at all pacing modes. Intrinsic physiologic effects of stress resulted in more accurate MD assessment with lesser variability in subjects who underwent pacing. LVRV20 was the preferred site of stimulation in this model rather than single-site pacing.