A novel suite of cyclotides from Viola odorata: sequence variation and the implications for structure, function and stability

Cyclotides are a fascinating family of plant-derived peptides characterized by their head-to-tail cyclized backbone and knotted arrangement of three disulfide bonds. This conserved structural architecture, termed the CCK (cyclic cystine knot), is responsible for their exceptional resistance to thermal, chemical and enzymatic degradation. Cyclotides have a variety of biological activities, but their insecticidal activities suggest that their primary function is in plant defence. In the present study, we determined the cyclotide content of the sweet violet Viola odorata, a member of the Violaceae family. We identified 30 cyclotides from the aerial parts and roots of this plant, 13 of which are novel sequences. The new sequences provide information about the natural diversity of cyclotides and the role of particular residues in defining structure and function. As many of the biological activities of cyclotides appear to be associated with membrane interactions, we used haemolytic activity as a marker of bioactivity for a selection of the new cyclotides. The new cyclotides were tested for their ability to resist proteolysis by a range of enzymes and, in common with other cyclotides, were completely resistant to trypsin, pepsin and thermolysin. The results show that while biological activity varies with the sequence, the proteolytic stability of the framework does not, and appears to be an inherent feature of the cyclotide framework. The structure of one of the new cyclotides, cycloviolacin O14, was determined and shown to contain the CCK motif. This study confirms that cyclotides may be regarded as a natural combinatorial template that displays a variety of peptide epitopes most likely targeted to a range of plant pests and pathogens.

A graduate viola recital with extended program notes

The extended program notes include historical facts of the composers and characteristics of the pieces being performed. The graduate viola recital will include the following works: Concerto in D-Major by Franz Anton Hoffmeister, Suite No. I in G-Major by Johann Sebastian Bach, and Sonata in A-Minor (Arpeggione) by Franz Schubert.

Sugestões performáticas do bilhete de um jogral para viola sozinha e das três peças para viola e piano de César Guerra-Peixe

This work is aimed at providing an interpretive study of the work for viola and piano titled Three Pieces, and work for solo viola titled Ticket of a Jogral, by Brazilian composer César Guerra Peixe. This study will be divided into three parts: The first will bring a brief history of the composer focusing on his visit to Pernambuco in the late 1940s and early 1950s; the second shows the use of Pernambuco musical regionalism elements used by the composer in the aforementioned documents; the third will present a set of interpretive suggestions based: the analysis of regional musical elements identified in these works; the technical rudiments used in writing for viola depicting the arcades, dynamics, fingerings, articulations, phrasing; and the experiences lived by the author of this research as an interpreter of these works.

Sugestões performáticas do bilhete de um jogral para viola sozinha e das três peças para viola e piano de César Guerra-Peixe

This work is aimed at providing an interpretive study of the work for viola and piano titled Three Pieces, and work for solo viola titled Ticket of a Jogral, by Brazilian composer César Guerra Peixe. This study will be divided into three parts: The first will bring a brief history of the composer focusing on his visit to Pernambuco in the late 1940s and early 1950s; the second shows the use of Pernambuco musical regionalism elements used by the composer in the aforementioned documents; the third will present a set of interpretive suggestions based: the analysis of regional musical elements identified in these works; the technical rudiments used in writing for viola depicting the arcades, dynamics, fingerings, articulations, phrasing; and the experiences lived by the author of this research as an interpreter of these works.

Der sterbende Jesus in einer Cantata : à basso solo con 2 hautbois, 2 violini, 1 viola, violoncello et organo

di Telemann

Introdução à música contemporânea portuguesa de viola d’arco : um estudo de caso

Esta dissertação baseia-se no estudo da introdução da música contemporânea portuguesa de viola d’arco num grupo de alunos de viola d’arco da Casa Pia de Lisboa, através de composições encomendadas a nove compositores portugueses. Incide também na análise das atitudes em relação à música contemporânea portuguesa por parte de professores de viola d’arco portugueses. Procurou-se ampliar o repertório da viola d’arco através da encomenda de obras didáticas, e o repertório expressivo dos alunos envolvidos. Verificou-se que a introdução tardia da música contemporânea no ensino da música e a desatualização dos programas podem condicionar a atitude dos músicos em relação à mesma, sendo importante uma mudança de paradigma. Parecem não existir dificuldades técnicas na abordagem a estas obras por parte dos alunos. Houve também uma aceitação por parte dos professores em introduzir estes conceitos, tendo existido igualmente uma abertura por parte dos compositores contemporâneos envolvidos, em criar obras didáticas para viola d’arco.

NEW PERSPECTIVES: TRANSCRIPTIONS FOR VIOLA

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. 

VIOLA MUSIC FROM THE AMERICAS: MUSIC FROM CANADA, UNITED STATES, CUBA, VENEZUELA, MEXICO, AND BRAZIL

The enthusiasm towards writing music for the viola that flourished in the early 1900’s thanks to the efforts of a number of twentieth-century violists and composers rapidly spilled over to North and South America. Viola works by American and Canadian composers have already become cornerstones of the viola repertoire worldwide. On the other hand, compositions from other parts of the American continent remain lesser known outside of their country of origin. This is due in part to the less developed publishing and recording industry in these countries which makes it difficult for performers and programmers from other countries to buy or rent performing materials. As a violist born and trained in Venezuela, performing works by important Latin American composers to new audiences is deeply important to me. This dissertation was completed by performing selected works by Canadian, American, Cuban, Mexican, Brazilian, and Venezuelan composers. Composers from these countries have mixed their rich musical traditions with modern compositional techniques, creating original works that have greatly enriched the viola repertoire. This eclectic mixture of styles makes the music from Latin American composers not only very different from that of American and Canadian composers, but also very different from those of their neighboring countries. Through my three dissertation recitals, I intend to share this music with new audiences and inspire other violists to become familiar with this repertoire. The first recital includes compositions by American composers George Rochberg (1918-2015), Elliott Carter (1908-2012), and Alan Shulman (1915-2002) and Canadian composer Elizabeth Raum (b. 1945). The second recital includes works by Cuban composers Cesar Orozco (b. 1980), and Keyla Orozco (b. 1969), Venezuelan composers Aldemaro Romero (1928-2007) and Modesta Bor (1926-1998), and Venezuelan-Uruguayan composer Efrain Oscher (b. 1974). The third recital includes works by Mexican composers Carlos Chavez (1899-1978), José Pablo Moncayo (1912-1958) and Manuel M Ponce (1882-1948), and Brazilian composers Francisco Mignone (1897-1986) and Brenno Blauth (1931-1993). This music represents a bouquet of a distinctive mixture of styles from different parts of the American continent. Recordings of all three recitals can be accessed at the University of Maryland Hornabake Library.

Sobre música portuguesa para viola d’arco no séc. XX: a influência de François Broos (1903-2002) na criação musical em Portugal

A presente dissertação procura explorar a figura que foi François Broos. Contactando alguns antigos colegas e alunos, procurou-se retratar de forma fidedigna o seu percurso pessoal e profissional, e de que forma a sua vinda para Portugal terá alterado o panorama nacional violetístico, tanto a nível educacional, como artístico. Procurou-se abordar, também, as relações pessoais e profissionais que estabeleceu, tanto no Porto como em Lisboa, com figuras de referência da música em Portugal. Assim, fez-se um breve itinerário pela produção musical para viola no século XX e, de igual forma, uma lista das obras de compositores portugueses para viola e piano ou viola e orquestra, de 1900 a 2000, de forma a verificar se, de facto, houve algum crescimento na produção nacional na música para viola desde que François Broos se instalou em Portugal, e indicar quantas dessas obras lhe terão sido dedicadas. Na segunda parte desta dissertação, e no seguimento do ponto acima mencionado, foram escolhidas duas obras de grande relevância no repertório português para viola, ambas dedicadas ao professor Broos, para serem analisadas do ponto de vista artístico, valorizando os aspetos técnicos da performance, através das respetivas gravações disponíveis.