923 resultados para tone


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On Seminar Day—Caltech’s annual reunion event—May 19, 2012, for the first time the Caltech Archives and Library offered alumni/ae the opportunity to record mini-interviews with Archives’ staff. Nine people participated, including one alumni spouse and one daughter. These alums held bachelor’s, master’s and doctoral degrees across several divisions, with engineering marginally in the lead. One former student who transferred out of Caltech came back to relate how well his Caltech years had served him in his later studies and career in psychology. Ranging from 10 to 15 minutes in length, the interviews typically relate stories or episodes from student years. Favorite topics include pranks and traditions, some of which have died out. Alumni also reflect on professors and classes which were memorable and on the unique intellectual stimulus that a Caltech education provides. Readers will find that the transcripts of the short interviews reflect the personal and colloquial tone at which the event aimed.

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One must only glance upon Franz Zeyringer’s 400-page, exhaustive Literatur für Viola to understand the error of the familiar but casual criticism of the paucity of the viola catalogue. Examining Zeyringer’s resource, however, we find a trend: while the viola repertoire contains many pieces (over 14,000 works) and does lay claim to many masterworks (Bartok’s Viola Concerto, Hindemith’s Sonatas, Mozart’s Sinfonia Concertante, etc.), many of the pieces originally written for the instrument are not widely recognized compositions and not often considered outstanding achievements. The violist, much like the double-bassist, bassoonist, and hornist, faces a certain challenge when selecting repertoire for a recital: a lack of large, important works that both fit the instrument and challenge the recitalist. This project will aim to expand recital repertoire for the viola through the development of new transcriptions, using the previously transcribed Fantasy Pieces by Schumann (trans. Leonard Davis) and Sonata No. 2 in E-flat, Op. 120 by Brahms (trans. Brahms) as an inspiration and guide. As a result, the catalogue of viola repertoire will not only be increased but the difference in tone and depth of the instrument may unveil previously unnoticed perspectives on the works. With a primary aim to expand the literature of the viola through the development of new transcriptions, this project will also strive to offer new, previously unnoticed perspectives on preexisting works. Through the changing of the instrumentation, listeners and performers will have the opportunity to explore the character of the compositions in a fresh and possibly illuminating way. Perhaps this project will encourage previously unexplored transcriptions to be realized and performed. While the recital repertoire for the viola boasts many and great works, the original transcriptions of this project attempt to infuse the collection with new and interesting possibilities for both study and performance. This dissertation project is comprised of three recitals featuring works transcribed for viola and, in most cases, newly transcribed by myself. All events took place on the campus of University of Maryland, College Park: Recital #1 on November 9, 2014 in the Gildenhorn Recital Hall of the Clarice Smith Performing Arts Center; Recital #2 on May 9, 2015, in Ulrich Recital Hall; and Recital #3 on November 6, 2015, in the Gildenhorn Recital Hall. 

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In Australia, sweetpotato production has grown remarkably (1700%) in the last 16 years. Growers currently market 75 000 t per annum, worth $80-90 million at farm gate. The orange-fleshed cultivars are the most familiar to consumers, but other cultivars with varying flesh colour and properties also have potential for the consumer market. Given that Australian sweetpotato growers desire alternative cultivars to promote market demand, it is important to articulate the characteristics of sweetpotatoes that are most and least desirable for consumers. Research indicates that consumer acceptability of the new cultivar 'Evangeline' may assist sweetpotato growers and marketers in understanding the impact of both sensory properties, such as colour and the importance of flavour and texture of sweetpotatoes, and an awareness of the potential health benefits of sweetpotato consumption. In addition, whilst consumer preferences (regarding size, colour, texture, skin tone) and nutritional knowledge of sweet potato (regarding glycaemic index) is increasing, there is limited research investigating consumers understanding of health messages of sweetpotato attributes. This industry and consumer research review highlights the potential for promoting innovative strategies to improve adoption of new cultivars in the marketplace.

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Colour words abound with figurative meanings, expressing much more than visual signals. Some of these figurative properties are well known; in English, for example, black is associated with EVIL and blue with DEPRESSION. Colours themselves are also described in metaphorical terms using lexis from other domains of experience, such as when we talk of deep blue, drawing on the domain of spatial position. Both metaphor and colour are of central concern to semantic theory; moreover, colour is recognised as a highly productive metaphoric field. Despite this, comparatively few works have dealt with these topics in unison, and even those few have tended to focus on Basic Colour Terms (BCTs) rather than including non-BCTs. This thesis addresses the need for an integrated study of both BCTs and non-BCTs, and provides an overview of metaphor and metonymy within the semantic area of colour. Conducted as part of the Mapping Metaphor project, this research uses the unique data source of the Historical Thesaurus of English (HT) to identify areas of meaning that share vocabulary with colour and thus point to figurative uses. The lexicographic evidence is then compared to current language use, found in the British National Corpus (BNC) and the Corpus of Contemporary American (COCA), to test for currency and further developments or changes in meaning. First, terms for saturation, tone and brightness are discussed. This lexis often functions as hue modifiers and is found to transfer into COLOUR from areas such as LIFE, EMOTION, TRUTH and MORALITY. The evidence for cross-modal links between COLOUR with SOUND, TOUCH and DIMENSION is then presented. Each BCT is discussed in turn, along with a selection of non-BCTs, where it is revealed how frequently hue terms engage in figurative meanings. This includes the secondary BCTs, with the only exception being orange, and a number of non-BCTs. All of the evidence discussed confirms that figurative uses of colour originate through a process of metonymy, although these are often extended into metaphor.

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This thesis is comprised of three parts: a critical dissertation, a creative work of fiction and a bridge piece that connects the two. The critical work is an examination of the Devil as a satirist in Faustian bargains. Through the usage of the Devil as a literary figure, his character has become a more secular being: a trickster rather than evil incarnate—a facilitator of sin rather than its originator. In the tragicomedy of pacts with the Devil, he acts as a mirror, reflecting mankind’s foibles and vanity, while elevating the reader in the process. The thesis considers the language, tone, purpose and conceits of several versions of the story. While the focus is primarily on American Literature, the influence of English, Scottish, French and German folklore and fiction are recognized as an essential component of the theme’s evolution. In the bridge piece, the pact with the Devil is literalized in a modern context; a corporate business of reaping souls is theorized in which techniques of persuasion are streamlined into an effective formula. Whether immersive or expository in approach, the portrayal of the supernatural depends on the literary principles of science fiction and fantasy in order to manipulate the reader and allow irrational concepts to obey rational laws. Such theories are cited to support how the Devil functions as a believable character. The novel, Could Be Much Worse, relates the story of an egocentric boss and his dependable employee, a scout who disguises himself as a taxi driver and seeks candidates who may succumb to temptation. Passengers’ monologues of desperation and pathos are interspersed throughout the protagonist’s day-to-day narrative. At times, the work is experimental, utilizing irregular storytelling techniques, alternative forms and conceits. Light-hearted, but nonetheless poignant, the story serves as a cautionary tale, illustrating the tedium of a bureaucratic job in a transmundane existence.

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The aim of this thesis was to investigate the electrical and mechanical responses to inhibitory non-adrenergic noncholinergic (NANC) nerve stimulation in the bovine retractor penis muscle (BRP) and compare them with those to an inhibitory extract made from this muscle. The extract may contain the NANC inhibitory transmitter of the BRP and possibly of other smooth muscles. Because of species differences in the electrical response to NANC nerves in the rat and rabbit anococcygeus the effects of the extract on these tissues was also investigated. Prior to the investigation of the extract, both the excitatory and inhibitory responses to field stimulation in the BRP, and the effects of passive membrane potential displacement were studied using conventional intra- or extracellular (sucrose gap) recording techniques. The majority of cells in the BRP were electrically quiescent independent of the resting tone. The most frequent (in approximately 25% of preparations) form of spontaneous activity, oscillations in membrane potential and tone, may represent a pacemaker activity. The BRP had cable properties; the time constant and space constant indicated a high membrane resistance. In the absence of tone, field stimulation of the BRP evoked excitatory junction potentials (ejps) in every cell impaled and contractions, graded with the strength, frequency and number of pulses; spikes were not observed. Guanethidine (1-3 x 10-5M) abolished the ejps and contractions, confirming their adrenergic origin. Noradrenaline added exogenously depolarised and contracted the muscle. These effects were blocked by the a-adrenoceptor antagonists, phentolamine and prazosin. However, phentolamine (2.5x 10-6M) inhibited the contraction without reducing the ejp significantly. These effects may be independent of adrenoceptor blockade or the ejp may be mediated by a substance other than noradrenaline (e.g. ATP) released from adrenergic nerves. Prazosin (1.4 x lO-6M) failed to block either the ejp or contraction, indicating the possible existence of two types of adrenoceptor in the BRP; one activated by neuronally-released and the other by exogenously-added noradrenaline. ATP, a contaminant in the extract, also depolarised and contracted the BRP. Physostigmine reduced whilst atropine enhanced the ejps and contractions without similarly affecting the response to exogenous noradrenaline. This confirmed the presence of a cholinergic inhibitory innervation acting on the excitatory adrenergic fibres (Klinge and Sjostrand, 1977). TEA (1 x lO-4M) enhanced the ejp and contraction. Higher concentrations (0.5 to 10 x 10-3M) depolarised, increased the tone and evoked electrical and mechanical oscillations but no spikes. The depolarisation and contraction to exogenous noradrenaline were not enhanced, indicating that TEA acts on the adrenergic nerves. Some post-synaptic effect to block K+ channels also seems likely. The relationship between ejp amplitude and membrane potential in the double sucrose gap was linear and indicated a reversal potential more positive than -30mV. Electrotonic pulse amplitude decreased during the ejp, indicating an increased membrane conductance. Ejps and contractions were reduced following the replacement of the NaCl of the Krebs solution with sodium glutamate. This may be due to the effects of glutamate itself (e.g. Ca2+ chelation) rather than reduction in the membrane Cl- gradient. Tone usually developed spontaneously and was accompanied by membrane depolarisation (from -53 to -45mV) which may open voltage-dependent channels, causing Ca2+ entry and/or its release from intracellular binding sites. Field stimulation produced inhibitory potentials (ijps) and relaxations graded with the strength and number of pulses but showing little frequency dependence. Rebound depolarisation and contraction often followed the ijp and relaxation. Tetrodotoxin (3 x IO-6M), but not adrenergic or cholinergic antagonists, abolished the ijp and relaxation, confirming their non-adrenergic non-cholinergic neurogenic nature. The extract, prepared and acid-activated as described by Gillespie, Hunter and Martin (1981), hyperpolarised and relaxed the BRP, as did sodium nitroprusside and adenosine triphosphate (ATP). Unlike the activated extract or sodium nitroprusside, desensitisation to ATP occurred rapidly and without any change in the inhibitory electrical or mechanical responses to field stimulation. The ijp and relaxation in the BRP were insensitive to apamin but abolished by oxyhaemoglobin (4-8 x 10-6M), as were the responses to extract and sodium nitroprusside. In TEA (10-2M), field stimulation evoked relaxations with no accompanying electrical change. The ijp may be unconnected with or additional to another mechanism producing relaxation. The relationship between membrane potential and ijp in the BRP was non-linear. Ijp amplitude was initially increased during membrane potential displacement from -45mV to approximately -60mV. Thereafter (-60 to -l03mV) the ijp was reduced. Ijps were abolished at -27 and -103mV; reversal was not observed. The hyperpolarisation to extract was also enhanced during passive displacement of the membrane potential to more negative values (-57mV). Membrane resistance increased during the ijp. The extract produced inconsistent changes in membrane resistance, possibly because of the presence of more than one active component. K+ withdrawal failed to enhance the ijp or hyperpolarisation to extract and 20mM K+ did not abolish the the ijp at membrane potentials exceeding EK (-49mV). Thus, the ijp or hyperpolarisation to extract are unlikely to be mediated by an increased K+ conductance. Reducing the Cl- abolished the hyperpolarisation to field stimulation and extract. This occurred more quickly than the anticipated reduction in the Cl- gradient and may be due to Ca2+ chelation by the anion substitute (glutamate or benzenesulphonate) or blockade of the resting conductance which is normally inactivated by the transmitter. Ouabain (1-5x 10-5M), which reduces both the Na+ and Cl- gradients, abolished the ijp, implicating either of these ions as the ionic species involved. In the rat and rabbit anococcygeus, field stimulation and extract each reduced guanethidine-induced tone. This was unaccompanied in the majority of cells in the rat by any significant electrical response. In the remaining cells, inhibition of the membrane potential oscillations occurred. The rabbit anococcygeus differed in that inhibition of the electrical oscillations was observed in every cell exhibiting this behaviour. However, the majority of cells in the rabbit were electrically quiescent and showed only small hyperpolarisations to field stimulation and no electrical response to extract. Apamin (1 x 10-7M) failed to block the electrical and mechanical response to field stimulation in the rabbit but did inhibit transiently that to extract. The latter effect may be due to the initial excitatory effects of apamin. The similarities between the electrical effects of the extract and those of inhibitory nerve stimulation in the BRP, rat and rabbit anococcygeus muscles are generally consistent with their being mediated by the same active component. Moreover, the ijp in the BRP shows properties which have not been reported in other non-adrenergic noncholinergically innervated smooth muscles.

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This thesis considers Eliot's critical writing from the late 1910s till the mid-1930s, in the light of his PhD thesis - Knowledge and Experience in the Philosophy of F. H. Bradley - and a range of unpublished material: T S. Eliot's Philosophical Essays and Notes (1913- 4) in the Hayward Bequest (King's College, Cambridge University); T. S. Eliot's Family Papers in the T. S. Eliot Collection at the Houghton Library (Harvard University); and items from the Harvard University Archives at the Pusey Library. 'Me thesis offers a comprehensive view of Eliot's critical development throughout this important period. It starts by considering The Sacred Wood's ambivalence towards the metaphysical philosophy of F. H. Bradley and Eliot's apparent adoption of a scientific method, under the influence of Bertrand Russell. It will be argued that Eliot uses rhetorical strategies which simultaneously subvert the method he is propounding, and which set the tone for an assessment of his criticism throughout the 1920s. His indecision, in this period, about the label 'Metaphysical' for some poets of the seventeenth century, reveals the persistence of the philosophical thought he apparently rejects in 1916, when he chooses not to pursue a career in philosophy in Harvard. This rhetorical tactic achieves its fulfilment in Dante (1929), where Eliot finds a model in the medieval allegorical method and 'philosophical' poetry. Allegory is also examined in connection with the evaluation of Eliot's critical writings themselves to determine, for instance, the figurative dimension of his early scientific vocabulary and uncover metaphysical residues he had explicitly disowned but would later embrace. Finally, it is suggested that, the hermeneutics of allegory are historical and it is used here to test the relationship between Eliot's early and later critical writings, that is the early physics and the later metaphysics.

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Pretende-se, neste texto, oferecer uma leitura da peça seniana em um acto, Epimeteu, ou o Homem que Pensava Depois, que, num complexo e original registo trágico-fársico, conjuga, com grande signifi cado dramático e efi cácia teatral, mito e fantasia.

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The coming out process has been conceptualized as a developmental imperative for those who will eventually accept their same-sex attractions. It is widely accepted that homophobia, heterosexism, and homonegativity are cultural realities that may complicate this developmental process for gay men. The current study views coming out as an extra-developmental life task that is at best a stressful event, and at worst traumatic when coming out results in the rupture of salient relationships with parents, siblings, and/or close friends. To date, the minority stress model (Meyer, 1995; 2003) has been utilized as an organizing framework for how to empirically examine external stressors and mental health disparities for lesbians, gay men, and bisexual individuals in the United States. The current study builds on this literature by focusing on the influence of how gay men make sense of and represent the coming out process in a semi-structured interview, more specifically, by examining the legacy of the coming out process on indicators of wellness. In a two-part process, this study first employs the framework well articulated in the adult attachment literature of coherence of narratives to explore both variation and implications of the coming out experience for a sample of gay men (n = 60) in romantic relationships (n = 30). In particular, this study employed constructs identified in the adult attachment literature, namely Preoccupied and Dismissing current state of mind, to code a Coming Out Interview (COI). In the present study current state of mind refers to the degree of coherent discourse produced about coming out experiences as relayed during the COI. Multilevel analyses tested the extent to which these COI dimensions, as revealed through an analysis of coming out narratives in the COI, were associated with relationship quality, including self-reported satisfaction and observed emotional tone in a standard laboratory interaction task and self-reported symptoms of psychopathology. In addition, multilevel analyses also assessed the Acceptance by primary relationship figures at the time of disclosure, as well as the degree of Outness at the time of the study. Results revealed that participant’s narratives on the COI varied with regard to Preoccupied and Dismissing current state of mind, suggesting that the AAI coding system provides a viable organizing framework for extracting meaning from coming out narratives as related to attachment relevant constructs. Multilevel modeling revealed construct validity of the attachment dimensions assessed via the COI; attachment (i.e., Preoccupied and Dismissing current state of mind) as assessed via the Adult Attachment Interview (AAI) was significantly correlated with the corresponding COI variables. These finding suggest both methodological and conceptual convergence between these two measures. However, with one exception, COI Preoccupied and Dismissing current state of mind did not predict relationship outcomes or self-reported internalizing and externalizing symptoms. However, further analyses revealed that the degree to which one is out to others moderated the relationship between COI Preoccupied and internalizing. Specifically, for those who were less out to others, there was a significant and positive relationship between Preoccupied current state of mind towards coming out and internalizing symptoms. In addition, the degree of perceived acceptance of sexual orientation by salient relationship figures at the time of disclosure emerged as a predictor of mental health. In particular, Acceptance was significantly negatively related to internalizing symptoms. Overall, the results offer preliminary support that gay men’s narratives do reflect variation as assessed by attachment dimensions and highlights the role of Acceptance by salient relationship figures at the time of disclosure. Still, for the most part, current state of mind towards coming out in this study was not associated with relationship quality and self-reported indicators of mental health. This finding may be a function of low statistical power given the modest sample size. However, the relationship between Preoccupied current state of mind and mental health (i.e., internalizing) appears to depend on degree of Outness. In addition, the response of primary relationships figures to coming out may be a relevant factor in shaping mental health outcomes for gay men. Limitations and suggestions for future research and clinical intervention are offered.

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This thesis examines the role of Scots language verse translation in the second-generation or post-war Scottish Renaissance. The translation of European poetry into Scots was of central importance to the first-generation Scottish Renaissance of the nineteen twenties and thirties. As Margery Palmer McCulloch has shown, the wider cultural climate of Anglo-American modernism was key to MacDiarmid’s conception of the interwar Scottish Renaissance. What was the effect on second-generation poet-translators as the modernist moment passed? Are the many translations undertaken by the younger poets who emerged in the course of the nineteen forties and fifties a faithful reflection of this cultural inheritance? To what extent are they indicative of a new set of priorities and international influences? The five principal translators discussed in this thesis are Douglas Young (1913-1973), Sydney Goodsir Smith (1915-1975), Robert Garioch (1909-1981), Tom Scott (1918-1995) and William J. Tait (1918-1992). Each is the subject of a chapter, in many cases providing the first or most extensive treatment of particular translations. While the pioneering work of John Corbett, Bill Findlay and J. Derrick McClure, among other scholars, has drawn attention to the long history of literary translation into Scots, this thesis is the first extended critical work to take the verse translations of the post-MacDiarmid makars as its subject. The nature and extent of MacDiarmid’s influence is considered throughout, as are the wider discourses around language and translation in twentieth-century Scottish poetry. Critical engagement with a number of key insights from theoretical translation studies helps to situate these writers’ work in its global context. This thesis also explores the ways in which the specific context of Scots translation allows scholars to complicate or expand upon theories of translation developed in other cultural situations (notably Lawrence Venuti’s writing on domestication and foreignisation). The five writers upon whom this thesis concentrates were all highly individual, occasionally idiosyncratic personalities. Young’s polyglot ingenuity finds a foil in Garioch’s sharp, humane wit. Goodsir Smith’s romantic ironising meets its match in Scott’s radical certainty of cause. Tait’s use of the Shetlandic tongue sets him apart. Nonetheless, despite the great variety of style, form and tone shown by each of these translators, this thesis demonstrates that there are meaningful links to be made between them and that they form a unified, coherent group in the wider landscape of twentieth-century Scottish poetry. On the linguistic level, each engaged to some extent in the composition of a ‘synthetic’ or ‘plastic’ language deriving partly from literary sources, partly from the spoken language around them. On a more fundamental level, each was committed to enriching this language through translation, within which a number of key areas of interest emerge. One of the most important of these key areas is Gaelic – especially the poetry of Sorley MacLean, which Young, Garioch and Goodsir Smith all translated into Scots. This is to some extent an act of solidarity on the part of these Scots poets, acknowledging a shared history of marginalisation as well as expressing shared hopes for the future. The same is true of Goodsir Smith’s translations from a number of Eastern European poets (and Edwin Morgan’s own versions, slightly later in the century). The translation of verse drama by poets is another key theme sustained throughout the thesis, with Garioch and Young attempting to fill what they perceived as a gap in the Scots tradition through translation from other languages (another aspect of these writers’ legacy continued by Morgan). Beyond this, all of the writers discussed in this thesis translated extensively from European poetries from Ancient Greece to twentieth-century France. Their reasons for doing so were various, but a certain cosmopolitan idealism figures highly among them. So too does a desire to see Scotland interact with other European nations, thus escaping the potentially narrowing influence of post-war British culture. This thesis addresses the legacy of these writers’ translations, which, it argues, continue to exercise a perceptible influence on the course of poetry in Scotland. This work constitutes a significant contribution to a much-needed wider critical re-assessment of this pivotal period in modern Scottish writing, offering a fresh perspective on the formal and linguistic merits of these poets’ verse translations. Drawing upon frequently obscure book, pamphlet and periodical sources, as well as unpublished manuscripts in the National Library of Scotland and the Shetland Archives, this thesis breaks new ground in its investigation of the role of Scots verse translation in the second-generation Scottish Renaissance.

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In this contribution, a system identification procedure of a two-input Wiener model suitable for the analysis of the disturbance behavior of integrated nonlinear circuits is presented. The identified block model is comprised of two linear dynamic and one static nonlinear block, which are determined using an parameterized approach. In order to characterize the linear blocks, an correlation analysis using a white noise input in combination with a model reduction scheme is adopted. After having characterized the linear blocks, from the output spectrum under single tone excitation at each input a linear set of equations will be set up, whose solution gives the coefficients of the nonlinear block. By this data based black box approach, the distortion behavior of a nonlinear circuit under the influence of an interfering signal at an arbitrary input port can be determined. Such an interfering signal can be, for example, an electromagnetic interference signal which conductively couples into the port of consideration. © 2011 Author(s).

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Les Erythropoietin-producing hepatocyte (EPH) sont la plus grande famille de récepteurs tyrosine kinase. Leurs ligands, les éphrines (EFNs), sont aussi des molécules exprimées à la surface cellulaire. Les EPH/EFNs sont impliqués dans de nombreux processus biologiques. L'hypertension artérielle (PA) est une maladie chronique qui, aujourd'hui, est devenue un problème médical critique dans le monde entier et un enjeu de santé publique. La découverte de nouvelles thérapeutiques de l'hypertension sont d'une grande importance pour la santé publique. Jusqu’à tout récemment, il existe seulement quelques études concernant le rôle de l’axe EPH/EFNs sur la fonction des cellules musculaires lisses vasculaires (CMLV). Dans nos études précédentes, nous avons montré qu'EPHB6 et EFNB1, de concert avec les hormones sexuelles, régulent la PA. Dans la présente étude, nous avons constaté que les différents membres de la famille EPH/EFN peuvent réguler soit positivement, soit négativement, la contractilité des CMLV et la PA: tandis que EPHB4 et EFNB2 appartiennent à la première catégorie, EFNB1, EFNB3 et EPHB6 appartiennent à la deuxième. In vivo, des souris males, mais non pas des femelles, porteuses d’une mutation EPHB4 (KO) spécifique du muscle lisse présentent une PA diminuée, comparée aux souris témoins (WT). Les CMLV de souris EPHB4 KO, en présence de testostérone, ont montré une contractilité réduite lors de la stimulation par la phényléphrine (PE). Au niveau moléculaire, la phosphorylation de la protéine kinase II dépendante de Ca2+/calmoduline et de la kinase de la chaine légère de la myosine (CLM) est augmentée, tandis que la phosphorylation de la kinase de la CLM est réduite dans les CMLV KO lors de la stimulation par PE, par rapport au WT CMLV. Cela fournit une base moléculaire à la réduction de la PA et de la contractilité des CMLV chez les souris EPHB4 KO. EFNB2 est le ligand majeur de l’EPHB4. Comme attendu, les souris EFNB2 KO spécifique du muscle lisse avaient un phénotype de PA semblable, quoique non identique, aux souris EPHB4 KO. Les souris mâles EFNB2 KO, mais pas femelles, sous régime régulier ou riche en sel, présentent une PA réduite, par rapport à leurs homologues WT. Au niveau cellulaire, les CMLV des souris KO ont montré une contractilité réduite lors de la stimulation par PE par rapport aux témoins WT. Une région de l’acide aminé (aa) 313 à l’aa 331 dans la partie intracellulaire d’EFNB2 est essentielle pour la signalisation inverse qui régule la contractilité des CMLV, selon des études de mutation-délétion. Dans une étude de génétique humaine, nous avons identifié, dans le gène EFNB2, six SNP qui étaient associées significativement au risque d'hypertension artérielle, de façon dépendante du sexe, ce qui corrobore nos résultats chez les souris. En revanche, la délétion du gène EFNB3 (KO) chez les souris femelles aboutit à une PA élevée et à une augmentation des résistances des petites artères in vivo, améliore la contractilité des petites artères ex-vivo et augmente la contractilité des CMLV in vitro. Les souris mâles KO ont une PA normale, mais la castration conduit à une augmentation significative de la PA dans les souris KO, mais pas dans les souris WT. Les CMLV des souris KO femelles ont montré une phosphorylation accrue de la CLM et une phosphorylation réduite de la kinase de la CLM, ce qui fournit à nouveau une base moléculaire aux phénotypes de PA et de contractilité des CMLV observés. Ce changement de signalisation est attribuable à une protéine adaptatrice Grip1. En effet, dans une étude d'association pan génomique par le Consortium International pour la Pression Sanguine, un SNP dans le gène GRIP1 a approché le seuil de significativité de la valeur p pour son association avec la pression diastolique. Nos recherches, pour la première fois, ont révélé que EPH/EFNs sont de nouveaux composants dans le système de régulation de la PA. Les membres de la famille EPH/EFN peuvent agir comme des forces Yin et Yang pour régler finement le tonus des vaisseaux pour assurer l'homéostasie de la PA et de sa régulation. Ces effets de EPH/EFNs dépendent du sexe et des niveaux d’hormones sexuelles. À partir de ces nouvelles connaissances, nous pourrions développer une nouvelle thérapie personnalisée pour l’hypertension artérielle, utilisant des antagonistes d'hormones sexuelles ou des thérapies de remplacement d'hormones sexuelles, selon les niveaux d'hormones sexuelles des patients et les mutations dans les gènes de l'EPH/EFN.

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Dissertação de Mestrado apresentada ao Instituto Superior de Psicologia Aplicada para obtenção de grau de Mestre na especialidade de Psicologia Social e das Organizações.

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Dissertação de Mestrado apresentada ao Instituto Superior de Psicologia Aplicada para obtenção de grau de Mestre na especialidade de Psicologia Clínica.

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Despite its ornamental value, some Melocactus species (Cactaceae) are threatened by several factors and only sexual propagation is possible. Thus, artificial seed banks are an appropriate method for their ex situ conservation. Suitable methods to germinate and to monitor viability are necessary for the seeds of these species. This work explored the use of tetrazolium test for monitoring seed viability of two Melocactus species. There was a correlation between the percentage of stained embryos, considering different cover area or tone stain, and the germination percentage. Unviable embryos did not stain. The embryos curved shape can explain the partial stain on the most of cases.