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Žiniasklaidos įtaka lyderio įvaizdžiui 2008-ųjų metų Seimo rinkimuose / Media influences on the image of leaders in the parliamentary election of 2008Rimkutė, Asta 09 July 2011 (has links)
Šiais laikais politika vis labiau siejama su komunikacija. Tai lėmė sparti informacinių technologijų raida ir kartu tobulėjančios komunikacinės technologijos bei strategijos. Šiuolaikinės rinkėjų elgesio teorijos prieina išvadų, kad rinkėjas ieško politinės informacijos minimaliomis pastangomis. Kita, akivaizdi tendencija – rinkėjų sprendimams žymiai svarbesnis tampa politinis lyderis, o ne politinė partija ir jos ideologija. Emociniai, o ne ideologiniai veiksniai ima viršų rinkėjui pasirenkant, už kurį kandidatą balsuoti, todėl vis labiau politikoje žaidžiama įvaizdžiais ir emocijomis. Išvardintos rinkėjų elgesio ir politinės komunikacijos tendencijos parodo didėjančią politinio lyderio ir jo įvaizdžio reikšmę bei patvirtina gilesnė politiko įvaizdžio, jo konstravimo, ir žiniasklaidos įtakos politiniuose procesuose analizės reikalingumą. Šio darbo objektas – žiniasklaidos įtaka lyderio įvaizdžiui bei rinkimų rezultatams. Darbo tikslas – išsiaiškinti žiniasklaidos įtaką politinio lyderio įvaizdžiui ir Seimo rinkimų rezultatams. Nustatyti, ar egzistuoja ryšys tarp žiniasklaidoje pasirodžiusios neigiamos ir teigiamos informacijos apie kandidatą ir rinkimų rezultatų. Darbo uždaviniai: išsiaiškinti įvaizdžio sąvoką ir politiko įvaizdžio sudėtines dalis, apibrėžti politinio lyderio savybes, remiantis išanalizuota literatūra, apibendrinti įvaizdžio konstravimo procesą ir pateikti įvaizdžio konstravimo schemą, nustatyti atskirų šio proceso dalių tarpusavio sąveiką, išanalizuoti... [toliau žr. visą tekstą] / Nowadays politics becomes more and more related to communication. Fast growth of information technologies determines simultaneous development of communication strategies and technologies. Contemporary voters’ behavior theories say that voters put no or minimal effort to searching for political information. When making important political decisions people refer to the information that they can easily get or to the information which they receive as a side product of their other activities. Other obvious tendency of voters’ behavior shows that the leader and the image of the leader of political party becomes much more important than the ideology and political party itself. Not ideological but emotional factors are the basis for the political decisions. These tendencies make the image of politician and its construction an actual topic and worthy of deeper analysis. The object of this work is the media influences on the image of leaders in the parliamentary election of 2008. The aim of this thesis is to determine the media influence on the image of the leaders and the results of the parliamentary elections of 2008. The objectives of this work are: to define the term of the image and the composite parts of it, to define the common attributes of the political leaders, to structure the process of image making and to propose the scheme of the image construction process, to analyze popular images of politicians and political communications tendencies, to describe image communication... [to full text]
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FABRICATION AND STUDY OF AC ELECTRO-OSMOTIC MICROPUMPSGuo, Xin 07 May 2013 (has links)
In this thesis, microelectrode arrays of micropumps have been designed, fabricated and characterized for transporting microfluid by AC electro-osmosis (ACEO). In particular, the 3D stepped electrode design which shows superior performance to others in literature is adopted for making micropumps, and the performance of such devices has been studied and explored. A novel fabrication process has also been developed in the work, realizing 3D stepped electrodes on a flexible substrate, which is suitable for biomedical use, for example glaucoma implant.
There are three major contributions to ACEO pumping in the work. First, a novel design of 3D “T-shaped” discrete electrode arrays was made using PolyMUMPs® process. The breakthrough of this work was discretizing the continuous 3D stepped electrodes which were commonly seen in the past research. The “T-shaped” electrodes did not only create ACEO flows on the top surfaces of electrodes but also along the side walls between separated electrodes. Secondly, four 3D stepped electrode arrays were designed, fabricated and tested. It was found from the experiment that PolyMUMPs® ACEO electrodes usually required a higher driving voltage than gold electrodes for operation. It was also noticed that a simulation based on the modified model taking into account the surface oxide of electrodes showed a better agreement with the experimental results. It thus demonstrated the possibility that the surface oxide of electrodes had impact on fluidic pumping. This methodology could also be applied to metal electrodes with a native oxide layer such as titanium and aluminum. Thirdly, a prototype of the ACEO pump with 3D stepped electrode arrays was first time realized on a flexible substrate using Kapton polyimide sheets and packaged with PDMS encapsulants. Comprehensive experimental testing was also conducted to evaluate the mechanical properties as well as the pumping performance. The experimental findings indicated that this fabrication process was a promising method to create flexible ACEO pumps that can be used as medical implants and wearable devices. / Thesis (Ph.D, Mechanical and Materials Engineering) -- Queen's University, 2013-05-06 10:57:48.077
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Organizacijų ryšių su visuomene ypatumai socialinėse medijose / Public relations in social mediaNaujalytė, Ieva 25 June 2014 (has links)
Magistro baigiamojo darbo objektas – ryšiai su visuomene socialinėse medijose. Darbo tikslas – ištirti socialinių medijų taikymo ryšių su visuomene veikloje galimybes ir ypatumus ir nustatyti socialinių medijų nulemtą ryšių su visuomene kaitą. Uždaviniai: išanalizuoti ryšių su visuomene veiklos ypatumus; apibrėžti ir įvertinti interneto ir socialinių medijų įtaką ryšių su visuomene veiklai; ištirti ir nustatyti socialinių medijų lemiamą ryšių su visuomene veiklos kaitą, jos bruožus. Darbą sudaro 5 pagrindinės dalys: įvadas, ryšių su visuomene veiklos ypatumai, interneto ir socialinių medijų įtaka ryšių su visuomene veiklai, tyrimas – komunikacijos socialiniuose tinkluose atvejų analizė, išvados. / Master's thesis subject - public relations social media. The aim - to explore the application of social media public relations activities and characteristics of the social media-led changes in public relations. Objectives: To analyze the public relations business features, define and evaluate the influence of Internet and social media on public relations activities, to explore and identify changes in public relations caused by social media. Work consists of five main parts: introduction, specific of public relations activities, the influence of internet and social media on public relations activities, the case studies of communication in social networks, conclusions.
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Interface entre neurones et puces structurées électroniques pour la détection de potentiels d'actionLarramendy, Florian 22 February 2013 (has links) (PDF)
L'interface homme / machine a entraîné de nombreuses recherches en biotechnologie. Une partie de ces recherches portent sur les interconnexions cerveau / machine. En effet, le cerveau dispose de nombreuses connexions cérébrales par le biais de neurones. Ces neurones communiquent entre eux et propagent l'information grâce à un signal bio-électrique appelé potentiel d'action. L'objectif de ma thèse de doctorat est de mesurer ce signal à l'aide de transistors ionosensibles à effet de champ (Ion Sensitive Field Effect Transistor ISFET). Le procédé ISFET a été modifié pour obtenir un nouveau type de capteur baptisé NeuroFET. Les puces contenant les NeuroFETs ont entièrement été fabriquées au sein de la salle blanche du LAAS. La croissance des neurites doit être ensuite orientée pour que celles-ci passent sur les grilles des NeuroFETs. Pour se faire, nous avons choisi de les contraindre mécaniquement à l'aide de canaux microfabriqués en résine SU-8. Après avoir testé différentes méthodes non concluantes, nous avons développé notre propre technique basée sur la photolithographie par projection. En modifiant les paramètres de focalisation et d'exposition, il a été possible d'obtenir des canaux en forme d'arcs brisés en une seule insolation. Grâce à cette méthode nommée " SU-8 3D", nous avons finalement réalisé des réseaux de microcanaux biocompatibles en SU-8 en vue d'analyses neuronales. Notre partenariat avec l'Institut de la Vision à Paris, nous a permis d'utiliser ce réseau de canaux afin d'orienter la croissance des neurites. La puce NeuroFET a été mise en boitier sur un circuit imprimé, isolée électriquement et recouverte d'un cône de culture permettant la culture neuronale à l'échelle de la puce individuelle. Les potentiels d'actions des neurones de rétine de rat n'étant pas assez important pour être mesuré à partir de l'électronique développée, nous avons utilisé des neurones d'escargots d'eau Lymnaea Stagnalis. Après trois jours de culture, nous avons appliqué aux cellules un cycle de différentes toxines permettant d'alterner le déclanchement de potentiels d'actions spontanés et l'état de repos. Ce cycle nous a permis d'observer une activité neuronale et ainsi de valider le bon fonctionnement du système.
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Modernization of the Indian Air Force: security implications for South AsiaDominguez, Edgar M. 03 1900 (has links)
Approved for public release; distribution is unlimited / This thesis analyzes the Indian Air Force's (IAF) robust modernization campaign and explores why the IAF is on the path to transforming itself from an air force dedicated to air defense to one capable of global force projection. The stunning examples of airpower in the two Gulf Wars, Kosovo, and Afghanistan proved to the Indian leadership the value of modern airpower. Thanks to the amazing growth of the Indian economy, the IAF is gradually acquiring the weapon systems characteristic of a global aerospace force. Pakistan and China are concerned about the motivations behind IAF's modernization efforts and already have begun to improve their own air capabilities in response to any conventional or nuclear contingency. The responses of Pakistan, in particular, indicate the lowering of the nuclear threshold in South Asia. On the other front, a potential arms race between India and China is anticipated. The United States may be able to neutralize the damaging effects of India's military build-up by increasing its arms exports to both India and Pakistan. Specifically, the sale of American F-16s to both countries would fortify bilateral relation with the United States, maintain the fragile security balance in South Asia, and minimize China's influence in the region. / Captain, United States Air Force
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Caracterização funcional e estrutural de peroxidases dependentes de tiól da bactéria fitopatogênica Xylella fastidiosa / Functional and structural characterization of thiol-dependent peroxidases from the phytopathogenic bacterium Xylella fastidiosaHorta, Bruno Brasil 05 August 2009 (has links)
A bactéria fitopatogênica Xylella fastidiosa é o agente etiológico da Clorose Variegada dos Citros (CVC), que causa perdas anuais estimadas em US$ 100 milhões no Brasil. Durante o processo infeccioso, a geração extracelular de espécies ativas de oxigênio é um dos principais mecanismos de defesa da planta contra o patógeno. Em contrapartida, para se defender do estresse oxidativo imposto pelo hospedeiro, os fitopatógenos possuem mecanismos de defesa que incluem enzimas antioxidantes, como as peroxirredoxinas, alquil hidroperóxido redutase subunidade C (AhpC) e proteína comigratória com bacterioferritina (Bcp). As peroxirredoxinas são proteínas que utilizam suas cisteínas ativas para catalisar a redução de hidroperóxidos. Por análise proteômica, os produtos dos genes ahpc e bcp foram identificados no extrato celular protéico de X. fastidiosa (Smolka e col., 2003). Com o intuito de caracterizar funcional e estruturalmente as proteínas AhpC e Bcp de X. fastidiosa, clonamos e expressamos seus respectivos genes em Escherichia coli e purificamos as proteínas por cromatografia de afinidade a níquel. As proteínas recombinantes apresentaram atividade dependente de tiól de redução de peróxido de hidrogênio e hidroperóxidos orgânicos. A atividade peroxidase da AhpC e Bcp são dependentes, respectivamente, de alquil hidroperóxido redutase subunidade F (AhpF) e do sistema tiorredoxina. Paradoxalmente, a flavoproteína AhpF possui atividade NAD(P)H oxidase, que resulta na produção de peróxido de hidrogênio. As constantes de segunda ordem da reação das proteínas com peróxido de hidrogênio (da ordem de 107 M-1.s-1), determinadas pelo ensaio de cinética competitiva com peroxidase de raiz forte, indicam que ambas possuem atividades peroxidase equivalentes às apresentadas por glutationa peroxidases dependentes de selênio e catalases, ao contrário do descrito na literatura. Por SDS-PAGE não-redutor e pela quantificação de cisteínas livres por DTNB, verificamos que as proteínas possuem mecanismos catalíticos distintos: AhpC é uma 2-Cys Prx típica (com formação de ponte dissulfeto intermolecular), enquanto Bcp é uma 2-Cys Prx atípica (com formação de ponte dissulfeto intramolecular). Para AhpC, a atividade catalítica envolve as cisteínas conservadas (Cys-47 e Cys-165), em contraste, apenas através de estudos de mutação sítio-dirigida e espectrometria de massas conseguimos identificar os resíduos de cisteínas envolvidos na atividade catalítica da Bcp (Cys-47 e Cys-83). A caracterização estrutural de AhpC por cromatografia de exclusão molecular e espalhamento dinâmico de luz mostram que a proteína nativa é um decâmero estável, independentemente do estado de oxidação de suas cisteínas. A caracterização da estrutura cristalográfica de Bcp C47S, inédita para 2-Cys Prx atípicas que possuem as cisteínas ativas separadas por 35 aminoácidos, indica que a proteína possui o enovelamento característico das peroxirredoxinas e que as cisteínas ativas estão localizadas a uma distância média de 12,4 Å. Baseado em dicroísmo circular, apresentamos dados que indicam que a aproximação das cisteínas deve envolver um significativo rearranjo estrutural, que provavelmente se inicia com a formação do intermediário ácido sulfênico na cisteína peroxidásica (Cys-47). Assim, conseguimos elucidar o papel catalítico dessas proteínas, bem como identificar seus sistemas redutores, obtendo informações que podem ser relevantes para o entendimento do mecanismo da patogenicidade da X. fastidiosa. Os resultados apresentados neste trabalho podem contribuir para o desenvolvimento de novas técnicas de controle de praga para a doença CVC em citrus e outras que envolvam a bactéria X. fastidiosa. / The phytopathogenic bacterium Xylella fastidiosa is the etiological agent of Citrus Variegated Chlorosis (CVC) that causes losses of about 100 millions dollars per year in Brazil. During infection, reactive oxygen species play a central role in plant pathogen defense. To survive under oxidative stress imposed by the host, microorganisms express antioxidant proteins, including the peroxiredoxins alkyl hydroperoxide reductase subunit C (AhpC) and bacterioferritin comigratory protein (Bcp). Peroxiredoxins are peroxidases, which rely on an activated cysteine residue to catalyze the reduction of hydroperoxides. By proteome analysis, Smolka et al. (2003) identified the products of ahpc and bcp genes present in whole cell extract of X. fastidiosa. To characterize the function and structure of AhpC and Bcp protein, their genes were cloned in Escherichia coli and the corresponding proteins purified by nickel affinity chromatography. Recombinant proteins presented thiol-dependent peroxidase activity against hydrogen peroxide and organic hydroperoxides. AhpC and Bcp peroxidase activities are dependent on alkyl hydroperoxide reductase subunit F (AhpF), and on thioredoxin system, respectively. Paradoxically, AhpF flavoenzyme possesses hydrogen peroxide-forming oxidase activity. Contrary to classical assumptions, competitive kinetics employing horseradish peroxidase assays showed that the second-order rate constants of AhpC and Bcp reaction with hydrogen peroxide are in the order of 107 M-1.s-1, as fast as the activity of selenium-dependent glutathione peroxidases and catalases. Non-reducing SDS-PAGE and cysteine quantification using DTNB indicated different peroxidasic mechanisms: AhpC is a typical 2-Cys peroxiredoxin (with intermolecular disulfide bond formation), while Bcp is an atypical 2-Cys peroxiredoxin (with intramolecular disulfide bond formation). In contrast to the well-conserved AhpC cysteines responsible for the peroxidase activity (Cys-47 and Cys-165), only through site-specific mutagenesis and mass spectrometry we could identified the cysteine residues involved in the Bcp peroxidase activity (Cys-47 and Cys-83). Structural characterization by size exclusion chromatography and dynamic light scattering revealed that AhpC native protein forms stable and redox state independent decamers. The crystal structure of Bcp C47S, the first 2-Cys Prx with a 35-residue between the active cysteines ever characterized, shows that protein contains the common fold of peroxiredoxins and that active cysteines lies ~12.4 Å away one from the other. Based on circular dichroism, we presented data indicating that disulfide bond formation may require significant conformational changes, which probably is triggered by the peroxidatic cysteine oxidation to sulfenic acid. In conclusion, we elucidated the catalytic mechanisms and reduction systems of AhpC and Bcp proteins that may help to understand the pathogenicity mechanism of X. fastidiosa. These results can contribute to the development of plague control methods against X. fastidiosa.
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The structure of ownership in family firms. / CUHK electronic theses & dissertations collection / Digital dissertation consortiumJanuary 2010 (has links)
Prior literature focuses on the causes and effects of ownership concentration between significant blockholders and minority shareholders. Anecdotal evidence shows that it is also important to look at the causes and effects of ownership concentration within controlling families as family ownership can become diffused after generations. Family trust is a popular vehicle for holding family ownership. It allows a founder to concentrate firm ownership on a long-term basis, preventing control loss after he/she steps down. Family members can enjoy control benefits such as preservation of their family intangible assets. However, there is tradeoff. Family members cannot resolve their conflicts by acquiring and selling off shares among them, since they are no longer the legal owners of the shares. / Using a sample of 216 family firms listed on the Hong Kong Stock Exchange with time series data spanning 1990--2008, I investigate the causes and effects of ownership concentration by means of family trust. I fmd that when family control is important (when there exists a large amount of family intangibles), there is a higher propensity that family trust is used to concentrate ownership and secure control, provided that the cost of using it is low (small family size hence low family conflict). However, when there are more and more family members after generations, the benefit of preserving the intangibles may not be high enough to cover the cost of potential family conflict, leading to firm value loss. Moreover, the cost of using trust magnifies during difficult periods such as financial distress, economic downturn and leadership succession. Hence, firms with high potential family conflict have poorer performance during difficult time if family trust is used for holding the firm's controlling stake. Family trust also induces common pool problem. Family members tend to extract resources from the family firm as much and as early as possible, leading to higher payout and slower firm growth. / Leung, Siu Ching. / Adviser: Joseph P. H. Fan. / Source: Dissertation Abstracts International, Volume: 73-03, Section: A, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaf 58). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
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Sildenafil reverte o fen?meno da vasoconstri??o pulmonar hip?xica em porcos rec?m-nascidosTessler, Rog?rio Blasbalg 02 April 2008 (has links)
Made available in DSpace on 2015-04-14T13:32:35Z (GMT). No. of bitstreams: 1
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Previous issue date: 2008-04-02 / O sildenafil ? um potente vasodilatador usado no tratamento da hipertens?o pulmonar persistente do rec?m nascido, entretanto existe conflito sobre os dados referentes ao efeito sobre a oxigena??o. Testamos o efeito sobre a vasoconstri??o pulmonar hip?xica (HPV) em porcos rec?m nascidos. Um segmento do pulm?o atelect?tico foi criado atrav?s da obstru??o de um br?nquio. O fluxo sangu?neo total e o fluxo local para o lobo atelect?tico e o lobo contra-lateral foram mensurados atrav?s da resson?ncia magn?tica nuclear (MRI), 30 minutos e ap?s a administra??o de sildenafil (0.2 e 1mg/kg ev) ou solu??o salina. O fluxo estava reduzido (P<0.01) no lobo atelect?tico e aumentado no lobo contra-lateral, indicando uma resposta da HPV adequada. Sildenafil nas doses oferecidas significativamente (P<0.01) aumenta o fluxo local para o lobo atelect?tico. Na dose de 1mg/Kg causa uma diminui??o da PaO2 de 285?37 para 161?22 mmHg (P<0.01). N?s conclu?mos que o rec?m nascido apresenta uma resposta HPV adequada, que interrompe quase por completo o fluxo de sangue para ?reas n?o ventiladas do pulm?o. Esse fen?meno ? revertido ap?s a administra??o do sildenafil endovenoso de forma dose dependente. Na presen?a de doen?a do par?nquima pulmonar, o uso de sildenafil endovenoso para o tratamento de hipertens?o pulmonar pode piorar a oxigena??o atrav?s da revers?o da resposta pulmonar vasoconstritora nas ?reas n?o ventiladas do pulm?o.
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Comparison of the sutherlandioside B levels in two commercially available Sutherlandia frutescence preparations and the effect of elevated temperature and humidity on these levelsJoseph, Ashton Edward January 2009 (has links)
Magister Pharmaceuticae - MPharm / Sutherlandia frutescens (tribe Galegeae, Fabaceae), is a popular medicinal plant traditionally used in South Africa. In 2000, a company called Phyto Nova (Pty) Ltd. initiated large-scale cultivation and contract manufacturing of tablets, made from the powdered herb (i.e. thin stems and leaves). Most of these commercial Sutherlandia solid dosage forms are made from the dried leaf powder but recently a new product, viz. Promune™ capsules, made from a freeze-dried aqueous extract, came on the market and was claimed to be “better” as it mimics the traditional tea. However, the pharmaceutical quality and stability of these preparations have not yet been investigated. The objectives of this study were firstly, to develop a validated stability-indicating HPLC assay for sutherlandioside B (SU-B); secondly, to compare the SU-B levels in the two commercially available Sutherlandia products viz, the Phyto Nova Sutherlandia SU1™ tablet and the Promune™ capsule, and, thirdly, to determine the effect of elevated temperature and humidity as well as acid hydrolysis on the SU-B levels in these two products. / South Africa
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Identification en imagerie Doppler : liens avec la transformée de radon généraliséeMennessier, Catherine 17 October 1997 (has links) (PDF)
Le champ magnétique des étoiles joue un rôle essentiel dans leur évolution interne et dans l'interaction qu'elles entretiennent avec leur environnement. Il se manifeste, entre autre, par l'existence de structures inhomogènes à leur surface. Hélas à de rares exceptions la résolution des télescopes reste insuffisante pour les résoudre spatialement. Ceci oblige donc à se tourner vers des méthodes indirectes. Telle est le but de l'imagerie Doppler. Après un exposé détaillé du principe de l'imagerie Doppler et quelques rappels sur la tomographie - transformée de Radon classique - nous montrons que cette technique astrophysique peut être traduite en termes de transformée de Radon généralisée. Cette réécriture du problème inverse d'imagerie Doppler permet d'étudier l'identifiabilité. Nous en déduisons, en particulier, l'existence de fonctions radiales du noyau. Des codes numériques performants utilisés classiquement en tomographie sont ensuite adaptés à notre type de mesure. Ils permettront de mieux caractériser les fonctions du noyau déduites de l'étude précédente. Nous nous intéressons ensuite à la géométrie d'échantillonnage des mesures en imagerie Doppler. Pour cela, nous étendons les résultats de schémas d'échantillonnage de la transformée de Radon classique à la transformée de Radon généralisée invariante par rotation avec fonction poids polynomiales. Ce résultat peut être appliqué à deux cas singuliers en imagerie Doppler. Par ailleurs, nous présentons les enjeux astrophysiques de l'imagerie Doppler : dans un premier temps sont résumées diverses manifestations du champ magnétique dans l'activité des étoiles, en particulier des étoiles jeunes T Tauri ainsi que le rôle de ce champ dans certains modèles d'évolution. Dans un deuxième temps sont données diverses techniques permettant d'estimer l'activité magnétique, parmi lesquelles l'imagerie Doppler dont la spécificité est soulignée. Enfin, cette technique est appliquée sur des données réelles issues d'observations que nous avons menées à l'Observatoire de Haute Provence. Des structures en surface sont déduites et les résultats sont discutés.
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