990 resultados para Ernest Mercier
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Zirconocene aldehyde and ketone complexes were synthesized in high yield by treatment of zirconocene acyl complexes with trimethylaluminum or diisobutylaluminum hydride. These complexes, which are activated by dialkylaluminum chloride ligands, inserted unsaturated substrates such as alkynes, allenes, ethylene, nitriles, ketenes, aldehydes, ketones, lactones, and acid chlorides with moderate to high conversion. Insertion of aldehyde substrates yielded zirconocene diolate complexes with up to 20:1 (anti:syn) diastereoselectivity. The zirconocene diolates were hydrolyzed to afford unsymmetrical 1,2-diols in 40-80% isolated yield. Unsymmetrical ketones gave similar insertion yields with little or no diastereoselectivity. A high yielding one-pot method was developed that coupled carbonyl substrates with zirconocene aldehyde complexes that were derived from olefins by hydrozirconation and carbonylation. The zirconocene aldehyde complexes also inserted carbon monoxide and gave acyloins in 50% yield after hydrolysis.
The insertion reaction of aryl epoxides with the trimethylphoshine adduct of titanocene methylidene was examined. The resulting oxytitanacyclopentanes were carbonylated and oxidatively cleaved with dioxygen to afford y-lactones in moderate yields. Due to the instability and difficult isolation of titanocene methylidene trimethylphoshine adducts, a one-pot method involving the addition of catalytic amounts of trimethylphosphine to β,β-dimethyltitanacyclobutane was developed. A series of disubstituted aryl epoxides were examined which gave mixtures of diastereomeric insertion products. Based on these results, as well as earlier Hammett studies and labeling experiments, a biradical transition state intermediate is proposed. The method is limited to aryl substituted epoxide substrates with aliphatic examples showing no insertion reactivity.
The third study involved the use of magnesium chloride supported titanium catalysts for the Lewis acid catalyzed silyl group transfer condensation of enol silanes with aldehydes. The reaction resulted in silylated aldol products with as many as 140 catalytic turnovers before catalyst inactivation. Low diastereoselectivities favoring the anti-isomer were consistent with an open transition state involving a titanium atom bound to the catalyst surface. The catalysts were also used for the aldol group transfer polymerization of t-butyldimethylsilyloxy-1-ethene resulting in polymers with molecular weights of 5000-31,000 and molar mass dispersities of 1.5-2.8. Attempts to polymerize methylmethacrylate using GTP proved unsuccessful with these catalysts.
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Background: 5'-deoxy-5'-methylthioadenosine (MTA) is an endogenous compound produced through the metabolism of polyamines. The therapeutic potential of MTA has been assayed mainly in liver diseases and, more recently, in animal models of multiple sclerosis. The aim of this study was to determine the neuroprotective effect of this molecule in vitro and to assess whether MTA can cross the blood brain barrier (BBB) in order to also analyze its potential neuroprotective efficacy in vivo. Methods: Neuroprotection was assessed in vitro using models of excitotoxicity in primary neurons, mixed astrocyte-neuron and primary oligodendrocyte cultures. The capacity of MTA to cross the BBB was measured in an artificial membrane assay and using an in vitro cell model. Finally, in vivo tests were performed in models of hypoxic brain damage, Parkinson's disease and epilepsy. Results: MTA displays a wide array of neuroprotective activities against different insults in vitro. While the data from the two complementary approaches adopted indicate that MTA is likely to cross the BBB, the in vivo data showed that MTA may provide therapeutic benefits in specific circumstances. Whereas MTA reduced the neuronal cell death in pilocarpine-induced status epilepticus and the size of the lesion in global but not focal ischemic brain damage, it was ineffective in preserving dopaminergic neurons of the substantia nigra in the 1-methyl-4-phenyl-1,2,3,6-tetrahydro-pyridine (MPTP)-mice model. However, in this model of Parkinson's disease the combined administration of MTA and an A(2A) adenosine receptor antagonist did produce significant neuroprotection in this brain region. Conclusion: MTA may potentially offer therapeutic neuroprotection.
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Background: The rising temperature of the world’s oceans has become a major threat to coral reefs globally as the severity and frequency of mass coral bleaching and mortality events increase. In 2005, high ocean temperatures in the tropical Atlantic and Caribbean resulted in the most severe bleaching event ever recorded in the basin. Methodology/Principal Findings: Satellite-based tools provided warnings for coral reef managers and scientists, guiding both the timing and location of researchers’ field observations as anomalously warm conditions developed and spread across the greater Caribbean region from June to October 2005. Field surveys of bleaching and mortality exceeded prior efforts in detail and extent, and provided a new standard for documenting the effects of bleaching and for testing nowcast and forecast products. Collaborators from 22 countries undertook the most comprehensive documentation of basin-scale bleaching to date and found that over 80% of corals bleached and over 40% died at many sites. The most severe bleaching coincided with waters nearest a western Atlantic warm pool that was centered off the northern end of the Lesser Antilles. Conclusions/Significance: Thermal stress during the 2005 event exceeded any observed from the Caribbean in the prior 20 years, and regionally-averaged temperatures were the warmest in over 150 years. Comparison of satellite data against field surveys demonstrated a significant predictive relationship between accumulated heat stress (measured using NOAA Coral Reef Watch’s Degree Heating Weeks) and bleaching intensity. This severe, widespread bleaching and mortality will undoubtedly have long-term consequences for reef ecosystems and suggests a troubled future for tropical marine ecosystems under a warming climate
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This memorandum has four parts. The first is a review and partial synthesis of Phase 1 and Phase 2 Reports by Dr. Ernest Estevez of the Mote Marine Laboratory to the Board of County Commissioners of Sarasota County, Florida. The review and synthesis emphasizes identification of the most important aspects of the structure of the Myakka system in terms of forcing functions, biological components, and major energy flows. In this context, the dominant primary producers, dominant fish species and food habits, and major environmental variables were of articular interest. A major focus of the review and synthesis was on the river zonations provided in the report and based on salinity and various biological indicators. The second part of this memorandum is a review of a draft report by Mote Marine Laboratory on evaluation of potential water quality impacts on the Myakka River from proposed activities in the watershed. This Memorandum's third part is a review of resource-management related ecosystem models in the context of possible future models of the Myakka River Ecosystem. The final part of this memorandum is proposed future work as an extension of the initial reports.
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Barkre, M.; Mathijs, E.; Sexton, J.; Egan, K.; Hunter, R. and Selfe, M. (2007). Audiences and Receptions of Sexual Violence in Contemporary Cinema. London: British Board of Film Classification. RAE2008
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Barker, Martin, Mathijs, Ernest, Watching the Lord of the Rings (Oxford, Peter Lang, 2008), pp.xiv+297 RAE2008
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http://books.google.com/books?vid=OCLC00289131
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The geography of Irish traditional music is a complex, popular and largely unexplored element of the narrative of the tradition. Geographical concepts such as the region are recurrent in the discourse of Irish traditional music but regions and their processes are, for the most part, blurred or misunderstood. This thesis explores the geographical approach to the study of Irish traditional music focusing on the concept of the region and, in particular, the role of memory in the construction and diffusion of regional identities. This is a tripartite study considering people, place and music. Each of these elements impacts on our experience of the other. All societies have created music. Music is often associated with or derived from places. Some places construct or reinforce their identity through the music and musicians through which they are associated. The thesis challenges conventional discourse on regional styles that construct an imagined pattern of regions based on subtle musical differences that may, though are not always, shared by people in that region and focuses on the social networks through which the music is disseminated. The thesis also challenges the abandonment of regional styles and the concept of regions in understanding the complex geographies of Irish traditional music (Morton, 2001). It seeks to find a middle ground between discourse analysis, musical analysis, the experience of music and place, and the representation of music and place. The dissertation is divided into three parts. Part one considers the development of music geography, noting and critiquing the abandonment of useful paradigms in both geography and ethnomusicology in search of new ways of understanding. Of particular interest is the concept of the region but it also considers the study of landscape and the humanist approach in cultural geography. The second part focuses on the discourse and study of regions in Irish traditional music and the various agents and processes that shape the concept of the region in Irish traditional music. The final part presents a case study of the Sliabh Luachra region combining and applying the various perspectives and paradigms drawn from geographical, ethnomusicological and anthropological sources. It attempts to generate an understanding of Sliabh Luachra as a region in the Irish traditional music narrative that is based on a combination of musical, socio-cultural and locational/environmental factors.
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The enculturation of Irish traditional musicians involves informal, non-formal, and sometimes formal learning processes in a number of different settings, including traditional music sessions, workshops, festivals, and classes. Irish traditional musicians also learn directly from family, peers, and mentors and by using various forms of technology. Each experience contributes to the enculturation process in meaningful and complementary ways. The ethnographic research discussed in this dissertation suggests that within Irish traditional music culture, enculturation occurs most effectively when learners experience a multitude of learning practices. A variety of experiences insures that novices receive multiple opportunities for engagement and learning. If a learner finds one learning practice ineffective, there are other avenues of enculturation. This thesis explores the musical enculturation of Irish traditional musicians. It focuses on the process of becoming a musician by drawing on methodologies and theories from ethnomusicology, education, and Irish traditional music studies. Data was gathered through multiple ethnographic methodologies. Fieldwork based on participant-observation was carried out in a variety of learning contexts, including traditional music sessions, festivals, workshops, and weekly classes. Additionally, interviews with twenty accomplished Irish traditional musicians provide diverse narratives and firsthand insight into musical development and enculturation. These and other methodologies are discussed in Chapter 1. The three main chapters of the thesis explore various common learning experiences. Chapter 2 explores how Irish traditional musicians learn during social and musical interactions between peers, mentors, and family members, and focuses on live music-making which occurs in private homes, sessions, and concerts. These informal and non-formal learning experiences primarily take place outside of organizations and institutions. The interview data suggests these learning experiences are perhaps the most pervasive and influential in terms of musical enculturation. Chapter 3 discusses learning experience in more organized settings, such as traditional music classes, workshops, summer schools, and festivals. The role of organizations such as Comhaltas Ceoltóirí Éireann and pipers’ clubs are discussed from the point of view of the learner. Many of the learning experiences explored in this chapter are informal, non-formal, and sometimes formal in nature, depending on the philosophy of the organization, institution, and individual teacher. The interview data and field observations indicate that learning in these contexts is common and plays a significant role in enculturation, particularly for traditional musicians who were born during and after the 1970s. Chapter 4 explores the ways Irish traditional musicians use technology, including written sources, phonography, videography, websites, and emerging technologies, during the enculturation process. Each type of technology presents different educational implications, and traditional musicians use these technologies in diverse ways and some more than others. For this, and other reasons, technology plays a complex role during the process of musical enculturation. Drawing on themes which emerge during Chapter 2, 3, and 4, the final chapter of this dissertation explores overarching patterns of enculturation within Irish traditional music culture. This ethnographic work suggests that longevity of participation and engagement in multiple learning and performance opportunities foster the enculturation of Irish traditional musicians. Through numerous and prolonged participation in music-making, novices become accustomed to and learn musical, social, and cultural behaviours. The final chapter also explores interconnections between learning experiences and also proposes directions for future research.
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This cultural history of Argentine crime fiction involves a comprehensive analysis of the literary and critical traditions within the genre, paying particular attention to the series of ‘aesthetic campaigns’ waged by Jorge Luis Borges and others during the period between 1933 and 1977. The methodological approach described in the introductory chapter builds upon the critical insight that in Argentina, generic discourse has consistently been the domain, not only of literary critics in the traditional mould, but also of prominent writers of fiction and specialists from other disciplines, effectively transcending the traditional tripartite ‘division of labour’ between writers, critics and readers. Chapter One charts the early development of crime fiction, and contextualises the evolution of the classical and hardboiled variants that were to provide a durable conceptual framework for discourse in the Argentine context. Chapter Two examines a number of pioneering early works by Argentine authors, before analysing Borges’ multi-faceted aesthetic campaign on behalf of the ‘classical’ detective story. Chapter Three examines a transitional period for the Argentine crime genre, book-ended by the three Vea y Lea magazine-sponsored detective story competitions that acted as a vital stimulus to innovation among Argentine writers. It includes a substantial treatment of the work of Rodolfo Walsh, documenting his transition from crime writer and anthologist to pioneer of the non-fiction novel and investigative journalism traditions. Chapter Four examines the period in which the novela negra came to achieve dominance in Argentina, in particular the aesthetic counter-campaigns conducted by Ricardo Piglia and others on behalf of the hard-boiled variant. The study concludes with a detailed analysis of Pablo Leonardo’s La mala guita (1976), which is considered as a paradigmatic example of crime fiction in Argentina in this period. The final chapter presents conclusions and a summary of the dissertation, and recommendations for further research.
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This dissertation centres on philosophical attitudes presented by North Indian classical musicians in relation to the concept and experience of rāga improvisation. In Hindustāni music, there is a dynamic tension ideology and pragmatism, devotion and entertainment, fixity and improvisational freedom, and cognition and visceral experience. On one hand, rāga is an embodied methodological template for the creation of music. On the other hand, rāga improvisation is conceptualised as a path to metaphysical experience and as an evocation of an ineffable divine presence. A masterful rendition of rāga is both a re-enactment of a systematic prescribed formula and a spontaneous flow of consciousness. This study presents these apparent dichotomies to highlight ideological concerns, while simultaneously contextualising philosophical idealism in relation to pragmatic realities. A central paradigm is the manner in which pragmatic concerns are elevated in status and given spiritual significance. The dissertation begins with a view into historical and religious context. The discussion continues with a speculative investigation positing co-relations between Hindustāni music and central tenets of Indian philosophy, considering how rāga improvisation may manifest as a philosophy of sound. The study then explores the concept of rāga, a modal and conceptual construct that forms the heart of Indian classical music. The final three sections ground the subject of spiritual ideology within the life experience of Hindustāni musicians: ‘Transmission’ looks at the learning and enculturation process, which encapsulates values intrinsic to the ethos of Hindustāni music culture. ‘Practice’ explores the discipline, science and experience of musical practice, revealing core ideological concerns connecting spirituality to musical experience; and ‘Performance’ examines the live presentation of rāga improvisation, and the relationship between music as ‘entertainment’ and music as ‘devotion’. Both ethnographic and musicological, this research is the culmination of various fieldtrips to India, extensive interviews with Hindustāni musicians, fifteen year’s sitār training, and the study of relevant musicological and philosophical texts.
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Barbara Hanning points out in her book Concise History of Western Music, that "Twentieth-century American music was in large measure an extension of European music" (Hanning 1998, 515). My dissertation/perforrnance project features cello works written by three contemporary composers who lived in America but were connected to the European heritage in different ways; each contributed significantly to the development of American classical concert life, music education, and even popular culture. Programs of my performances are intended to illustrate their unique compositional styles. The first recital consists of five cello compositions of Massachusetts-born Arthur Foote (1853 - 1937): Drei Stucke fur Pianoforte und Violoncello, Op. 1; Scherzo, Op.22; Romanza, Op.33; Aubade, Op.77; and Sonata for Violoncello and Piano, Op.78. Foote was influenced by the German-trained John Knowles Paine at Harvard University; he composed music famous for its extensive chromaticism in both harmony and melodic line, and for clearly-defined formal structure. The second recital explores the music of Swiss-American composer Ernest Bloch (1880-1959): a short Meditation Hebraique, a Suite No. I for Violoncello Solo and the famous rhapsody Schelomo. Born in Geneva, Switzerland, and settling in the United States in 1916, Bloch is a composer deeply influenced by the European late-Romantic tradition and is also well-known for employing "Hebraic" elements into his works. The final performance comprises two other of Bloch's cello works and one cello concerto by the Austrian-American composer, Erich Wolfgang Korngold (1897- 1957). Bloch's Voice in the Wilderness is a symphonic poem for orchestra and cello (accompanied by piano in this performance), consisting of six movements performed without pause. His Suite No.3 for Cello Solo is shorter and has a simpler style than the first Suite. Korngold was recognized as a child prodigy in his native Austria. After a Nazi-induced exile, he immigrated to America and became a film music composer in Hollywood. The Cello Concerto was used in the movie "Deception" (1 946), for which Korngold provided the film score. The impassioned harmonic language and lavish melodic lines inherited from the high-romanticism make this work one of comparative discordant beauty among other compositions of his time.
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In the late nineteenth century, French composers such as Camille Saint- Saens, Cesar Franck, and Claude Debussy worked to elevate instrumental music in late-Romantic period France, creating symphonies, concertos, and chamber ensembles, including duo sonatas. These composers and followers like, Ernest Chausson and Guillaume Lekeu were all influenced by a particular violinist to whom they dedicated their compositions. The primary violinist who inspired these composers was Eugene Ysaye (1858-1931), a brilliant performer and composer. His freedom of expression motivated many prominent French composers to dedicate major works to him. For example, Debussy dedicated his string quartet to Ysaye, who established the Ysaye Quartet and premiered Debussy's composition. In 1886, Franck completed his sonata for violin and piano which he also dedicated to Ysaye. Fritz Kreisler (1875-1962), one of the most talented violinists of his era, had a relationship withYsaye that was quite special. They respected, supported, and befriended each other. To Ysaye, Kreisler dedicated his Recitativo and Scherzo. To Kreisler, Ysaye dedicated one ofhis celebrated Sonatas for Solo Violin. Pablo de Sarasate (1844-1908) was a magnificent Spanish violinist of the late nineteenth century, and his music and performances influenced many composers, especially Saint-Saens, who included Spanish gypsy fragments in his works. These motifs may found in his Havanaise, Introduction and Rondo Capriccioso and Violin Concerto No.3 which were dedicated to Sarasate. My goal for this dissertation project has been to find and present, in three recitals, works by French composers and also works by the violinists who inspired them. As a violinist, I have endeavored to understand the influence of the various violinists on these French composers and how that knowledge can inform my approach to performing these works. In my first recital, with pianist Soo Young Jung, I performed works by Saint-Saens, Ysaye and Sarasate. With pianist Sun Ha Yoon, I performed works by Ysaye, Debussy, Kreisler and Franck in my second recital. My third recital, again with pianist Sun Ha Yoon, featured works by Ysaye, Chausson, and Lekeu. All recitals were recorded and performed at the University ofMaryland, College Park.
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© 2015, Jon C. Giullian and Ernest A. Zitser.The proliferation of research guides created using the LibGuides platform has triggered extensive discussion touting their benefits for everything from assessment, engagement, and marketing, to outreach and pedagogy. However, there is at present a relative paucity of critical reflection about the product’s place in the broader informational landscape. This article is an attempt to redress this lacuna. Relying primarily on examples from the field of Slavic, East European, and Eurasian studies, the authors briefly describe the evolution of online research guides; identify reasons for the proliferation of Springshare’s product in academic libraries; question whether LibGuides improve learning or reinforce information inequality in higher education; and propose a way to move beyond LibGuides.