Sex steroids and intestinal amino acid transport in rainbow trout, Salmo airdneri Richardson

The effects of sane anabolic and naturally-occuring sex steroids on intestinal transport of leucine have been studied in rainbow trout (Sallno gairdneri), in vivo (gut perfusion), and in vitro (everted gut sacs or intestinal strips). Administration of 17a-methyltestosterone (Mr) by injection for a prolo03ed period of time, enhanced intestinal transport and accumulation of leucine. 11-ketotestosterone (KT) or MT treatment in vitro, by direct addition to incubation media, elicited significant short-term increases in active transport of leucine, without effecting intestinal accumulation. Luminal administration of Mr in vivo similarly elicited short-term responses, without effecting leucine accumulation in the intestine or other peripheral tissues. However; neither MT nor KT significantly affected intestinal transport of water in trout. Although long term injection of oestradiol (E2) enhanced intestinal transport and accumulation of leucine, E2 treatment in vitro was without effect. Addition of ouabain or 2,4,dinitrophenol in the presence of MT abolished steroid-stimulated leucine transform, in vitro. No significant differences were observed between immature male or female trout with respect to either transport of leucine and water, or intestinal granular cell density. However, 'apparent' Na+ absorption and percentage fold height were higher in females, while total intestinal thickness and enterocyte heights were greater in males. These sex differences were essentially abolished. after gonadectany. It is suggested that the short-term effects of the androgenic steroids might be partly mediated through increased activity of Na+,K+,ATPase, and that steroid-induced growth promotion in fish may,to sane extent, be a consequence of enhanced efficiency of intestinal function.

Development of a microbicide-releasing diaphragm as an HIV prevention strategy

Contraceptive diaphragms offer a discreet method of pregnancy protection that women can use when needed with no side effects. Incorporating antiretroviral HIV microbicides into such devices may also provide protection against HIV infection. The paper gives a brief outline of the work being conducted by PATH, CONRAD and QUB on the development of a microbicide-releasing SILCS diaphragm. The design, engineering and manufacturing challenges that have been encountered will be discussed, as well as the potential impact such a device could have in the developing world.

The environmental control of reproduction in the female dace, Leuciscus leuciscus

An investigation was made into the nature and control of the annual reproductive cycle of the dace, Leuciscus leuciscus. It includes 1) a study of the natural reproductive cycle, 2) the use of Carp Pituitary Extract (CPE) to induce final maturation and ovulation in captive fish, 3) the effect of artificial light treatments on ovarian development and 4) the measurement of serum melatonin levels under different photoperiod regimes. Ovarian development was monitored by endocrinological data, notably serum cycles of 17-oestradiol (E2), testosterone (T), and calcium (as an index of vitellogenin), oocyte diameter, the gonadosomatic index and histological studies of the ovary. Under natural conditions, ovarian development can broadly be divided into 4 stages: 1) oogenesis which occurs immediately after spawning; 2) a primary growth phase (previtellogenic growth) prevalent between spawning and June; 3) a secondary growth phase (yolk vesicle plus vitellogenic growth) occurring between June and December and 4) final maturation and ovulation which occurs in mid-March. During the annual ovarian cycle, the sex steroids E2 and T showed two clear elevations. The first occurred initially in April followed by a rise in serum calcium levels. This subsequently initiated the appearance of yolk granules in the oocytes in June. The second rise occurred in September and levels were maintained until December, after which there was a decline in serum E2 levels. It is proposed that in the dace, high serum E2 levels between September and December were required to maintain vitellogenin production and therefore its uptake into the developing oocytes which occurred during this time, albeit at a slower rate than in the summer months. After December, prior to final maturation, whereas serum E2 and calcium levels declined, serum T levels remained elevated. In captivity, final maturation beyond the germinal vesicle migration stage failed to occur suggesting that the stimuli required for these events were absent. However ovulation could be induced by a single injection of CPE, which induced ovulation between 6 and 14 hours after treatment. Endocrine events associated with the artificial induction of spawning included a rise in serum levels of E2, T and the maturation inducing steroid 1720-dihydroxy progesterone. Photoperiodic manipulation demonstrated that whereas short or increasing daylengths were stimulatory to ovarian development, long days delayed development. Changes from long to short and constant short daylengths early in the reproductive cycle advanced maturation (up to 5 months), suggesting that the stimulus for ovarian development and maturation was a short day. However, experiments conducted later in the reproductive cycle demonstrated that only a simulated ambient photoperiod could induce final maturation. It is proposed therefore that under natural conditions the environmental stimulus for ovarian development and final maturation are short and increasing daylengths respectively. Further support that photoperiod is the dominant timing cue in this species was provided by the pattern of serum melatonin levels. Under different photoperiod treatments, serum melatonin, which is believed to be the chemical transducer of photoperiodic information (similar to other photoperiodic species) was elevated for the duration of the dark phase, indicating that the dace at least has the ability to `measure' changes in daylength.

Bacterial associations with salmonid eggs

Rainbow trout eggs Salmo gairdneri, Richardson, were incubated under a range of different environmental conditions. Recovery of bacteria from egg surfaces revealed that increased water temperature, slow water flow rates and high egg density all significantly increased egg surface bacterial populations. Live eggs were mainly colonized by Cytophaga sp., pseudomonas fluorescens and Aeromonas hydrophila. In contrast, dead eggs supported considerable numbers of fluorescent Pseudomonas sp. Analysis of potential nutrient sources for bacteria colonizing live egg surfaces revealed that small amounts of amino acids, phosphate and potassium may be lost by incubating eggs. Subsequently these nutrients were shown to be capable of supporting limited bacterial growth and reproduction. Dead eggs `leaked' increased amounts of the above nutrients which in turn supported higher bacterial numbers. In addition, biochemical analysis of eggs revealed amino acids and fatty acids that might be utilized by bacteria colonizing dead egg surfaces. Assessment of adhesion properties of bacteria frequently recovered from egg surfaces revealed high cell surface hydrophobicity as an important factor in successful egg colonization. Analysis of egg mortalities from groups of rainbow trout and brown trout (S.trutta L.) eggs maintained under two different incubation systems revealed that potentially a close correlation existed between egg surface bacterial numbers and mortalities in the egg during incubation. Innoculation of newly-fertilized eggs with bacteria demonstrated that groups of eggs supporting high numbers of P.fluorescens suffered significantly higher mortalities during the early part of their incubation. Exposure of incubating eggs to oxolinic acid, chlortetracycline and chloramphenicol demonstrated that numbers of bacteria on egg surfaces could be significantly reduced. However, as no corresponding increase in egg hatching success was revealed, the treatment of incubating eggs with antibiotics or antimicrobial compounds can not be recommended. In commercial hatcheries bacteria are only likely to be responsible for egg deaths during incubation when environmental conditions are unfavourable. High water temperatures, slow water flow rates and high egg density all lead to increased bacterial number of egg surfaces, reduced water circulation and low levels of dissolved oxygen. Under such circumstances sufficient amounts of dissolved oxygen may not be available to support developing embryos.

Une étude générique du metteur en scène au théâtre:son émergence et son rôle moderne et contemporain

The theatre director (metteur en scene in French) is a relatively new figure in theatre practice. It was not until the I820s that the term 'mise en scene' gained currency. The term 'director' was not in general use until the I880s. The emergence and the role of the director has been considered from a variety of perspectives, either through the history of theatre (Allevy, Jomaron, Sarrazac, Viala, Biet and Triau); the history of directing (Chinoy and Cole, Boll, Veinstein, Roubine); semiotic approaches to directing (Whitmore, Miller, Pavis); the semiotics of performance (De Marinis); generic approaches to the mise en scene (Thomasseau, Banu); post-dramatic approaches to theatre (Lehmann); approaches to performance process and the specifics of rehearsal methodology (Bradby and Williams, Giannachi and Luckhurst, Picon-Vallin, Styan). What the scholarly literature has not done so far is to map the parameters necessarily involved in the directing process, and to incorporate an analysis of the emergence of the theatre director during the modem period and consider its impact on contemporary performance practice. Directing relates primarily to the making of the performance guided by a director, a single figure charged with the authority to make binding artistic decisions. Each director may have her/his own personal approaches to the process of preparation prior to a show. This is exemplified, for example, by the variety of terms now used to describe the role and function of directing, from producer, to facilitator or outside eye. However, it is essential at the outset to make two observations, each of which contributes to a justification for a generic analysis (as opposed to a genetic approach). Firstly, a director does not work alone, and cooperation with others is involved at all stages of the process. Secondly, beyond individual variation, the role of the director remains twofold. The first is to guide the actors (meneur de jeu, directeur d'acteurs, coach); the second is to make a visual representation in the performance space (set designer, stage designer, costume designer, lighting designer, scenographe). The increasing place of scenography has brought contemporary theatre directors such as Wilson, Castellucci, Fabre to produce performances where the performance space becomes a semiotic dimension that displaces the primacy of the text. The play is not, therefore, the sole artistic vehicle for directing. This definition of directing obviously calls for a definition of what the making of the performance might be. The thesis defines the making of the performance as the activity of bringing a social event, by at least one performer, providing visual and/or textual meaning in a performance space. This definition enables us to evaluate four consistent parameters throughout theatre history: first, the social aspect associated to the performance event; second, the devising process which may be based on visual and/or textual elements; third, the presence of at least one performer in the show; fourth, the performance space (which is not simply related to the theatre stage). Although the thesis focuses primarily on theatre practice, such definition blurs the boundaries between theatre and other collaborative artistic disciplines (cinema, opera, music and dance). These parameters illustrate the possibility to undertake a generic analysis of directing, and resonate with the historical, political and artistic dimensions considered. Such a generic perspective on the role of the director addresses three significant questions: an historical question: how/why has the director emerged?; a sociopolitical question: how/why was the director a catalyst for the politicisation of theatre, and subsequently contributed to the rise of State-funded theatre policy?; and an artistic one: how/why the director has changed theatre practice and theory in the twentieth-century? Directing for the theatre as an artistic activity is a historically situated phenomenon. It would seem only natural from a contemporary perspective to associate the activity of directing to the function of the director. This is relativised, however, by the question of how the performance was produced before the modern period. The thesis demonstrates that the rise of the director is a progressive and historical phenomenon (Dort) rather than a mere invention (Viala, Sarrazac). A chronological analysis of the making of the performance throughout theatre history is the most useful way to open the study. In order to understand the emergence of the director, the research methodology assesses the interconnection of the four parameters above throughout four main periods of theatre history: the beginning of the Renaissance (meneur de jeu), the classical age (actor-manager and stage designer-manager), the modern period (director) and the contemporary period (director-facilitator, performer). This allows us properly to appraise the progressive emergence of the director, as well as to make an analysis of her/his modern and contemporary role. The first chapter argues that the physical separation between the performance space and its audience, which appeared in the early fifteenth-century, has been a crucial feature in the scenographic, aesthetic, political and social organisation of the performance. At the end of the Middle Ages, French farces which raised socio-political issues (see Bakhtin) made a clear division on a single outdoor stage (treteau) between the actors and the spectators, while religious plays (drame fiturgique, mystere) were mostly performed on various outdoor and opened multispaces. As long as the performance was liturgical or religious, and therefore confined within an acceptable framework, it was allowed. At the time, the French ecclesiastical and civil authorities tried, on several occasions, to prohibit staged performances. As a result, practitioners developed non-official indoor spaces, the Theatre de fa Trinite (1398) being the first French indoor theatre recognized by scholars. This self-exclusion from the open public space involved breaking the accepted rules by practitioners (e.g. Les Confreres de fa Passion), in terms of themes but also through individual input into a secular performance rather than the repetition of commonly known religious canvases. These developments heralded the authorised theatres that began to emerge from the mid-sixteenth century, which in some cases were subsidised in their construction. The construction of authorised indoor theatres associated with the development of printing led to a considerable increase in the production of dramatic texts for the stage. Profoundly affecting the reception of the dramatic text by the audience, the distance between the stage and the auditorium accompanied the changing relationship between practitioners and spectators. This distance gave rise to a major development of the role of the actor and of the stage designer. The second chapter looks at the significance of both the actor and set designer in the devising process of the performance from the sixteenth-century to the end of the nineteenth-century. The actor underwent an important shift in function in this period from the delivery of an unwritten text that is learned in the medieval oral tradition to a structured improvisation produced by the commedia dell 'arte. In this new form of theatre, a chef de troupe or an experienced actor shaped the story, but the text existed only through the improvisation of the actors. The preparation of those performances was, moreover, centred on acting technique and the individual skills of the actor. From this point, there is clear evidence that acting began to be the subject of a number of studies in the mid-sixteenth-century, and more significantly in the seventeenth-century, in Italy and France. This is revealed through the implementation of a system of notes written by the playwright to the actors (stage directions) in a range of plays (Gerard de Vivier, Comedie de la Fidelite Nuptiale, 1577). The thesis also focuses on Leoni de' Sommi (Quatro dialoghi, 1556 or 1565) who wrote about actors' techniques and introduced the meneur de jeu in Italy. The actor-manager (meneur de jeu), a professional actor, who scholars have compared to the director (see Strihan), trained the actors. Nothing, however, indicates that the actor-manager was directing the visual representation of the text in the performance space. From the end of the sixteenth-century, the dramatic text began to dominate the process of the performance and led to an expansion of acting techniques, such as the declamation. Stage designers carne from outside the theatre tradition and played a decisive role in the staging of religious celebrations (e.g. Actes des Apotres, 1536). In the sixteenth-century, both the proscenium arch and the borders, incorporated in the architecture of the new indoor theatres (theatre a l'italienne), contributed to create all kinds of illusions on the stage, principally the revival of perspective. This chapter shows ongoing audience demands for more elaborate visual effects on the stage. This led, throughout the classical age, and even more so during the eighteenth-century, to grant the stage design practitioner a major role in the making of the performance (see Ciceri). The second chapter demonstrates that the guidance of the actors and the scenographic conception, which are the artistic components of the role of the director, appear to have developed independently from one another until the nineteenth-century. The third chapter investigates the emergence of the director per se. The causes for this have been considered by a number of scholars, who have mainly identified two: the influence of Naturalism (illustrated by the Meiningen Company, Antoine, and Stanislavski) and the invention of electric lighting. The influence of the Naturalist movement on the emergence of the modem director in the late nineteenth-century is often considered as a radical factor in the history of theatre practice. Naturalism undoubtedly contributed to changes in staging, costume and lighting design, and to a more rigorous commitment to the harmonisation and visualisation of the overall production of the play. Although the art of theatre was dependent on the dramatic text, scholars (Osborne) demonstrate that the Naturalist directors did not strictly follow the playwright's indications written in the play in the late nineteenth-century. On the other hand, the main characteristic of directing in Naturalism at that time depended on a comprehensive understanding of the scenography, which had to respond to the requirements of verisimilitude. Electric lighting contributed to this by allowing for the construction of a visual narrative on stage. However, it was a master technician, rather than an emergent director, who was responsible for key operational decisions over how to use this emerging technology in venues such as the new Bayreuth theatre in 1876. Electric lighting reflects a normal technological evolution and cannot be considered as one of the main causes of the emergence of the director. Two further causes of the emergence of the director, not considered in previous studies, are the invention of cinema and the Symbolist movement (Lugne-Poe, Meyerhold). Cinema had an important technological influence on the practitioners of the Naturalist movement. In order to achieve a photographic truth on the stage (tableau, image), Naturalist directors strove to decorate the stage with the detailed elements that would be expected to be found if the situation were happening in reality. Film production had an influence on the work of actors (Walter). The filmmaker took over a primary role in the making of the film, as the source of the script, the filming process and the editing of the film. This role influenced the conception that theatre directors had of their own work. It is this concept of the director which influenced the development of the theatre director. As for the Symbolist movement, the director's approach was to dematerialise the text of the playwright, trying to expose the spirit, movement, colour and rhythm of the text. Therefore, the Symbolists disengaged themselves from the material aspect of the production, and contributed to give greater artistic autonomy to the role of the director. Although the emergence of the director finds its roots amongst the Naturalist practitioners (through a rigorous attempt to provide a strict visual interpretation of the text on stage), the Symbolist director heralded the modem perspective of the making of performance. The emergence of the director significantly changed theatre practice and theory. For instance, the rehearsal period became a clear work in progress, a platform for both developing practitioners' techniques and staging the show. This chapter explores and contrasts several practitioners' methods based on the two aspects proposed for the definition of the director (guidance of the actors and materialisation of a visual space). The fourth chapter argues that the role of the director became stronger, more prominent, and more hierarchical, through a more political and didactic approach to theatre as exemplified by the cases of France and Germany at the end of the nineteenth-century and through the First World War. This didactic perspective to theatre defines the notion of political theatre. Political theatre is often approached by the literature (Esslin, Willett) through a Marxist interpretation of the great German directors' productions (Reinhardt, Piscator, Brecht). These directors certainly had a great influence on many directors after the Second World War, such as Jean Vilar, Judith Molina, Jean-Louis Barrault, Roger Planchon, Augusto Boal, and others. This chapter demonstrates, moreover, that the director was confirmed through both ontological and educational approaches to the process of making the performance, and consequently became a central and paternal figure in the organisational and structural processes practiced within her/his theatre company. In this way, the stance taken by the director influenced the State authorities in establishing theatrical policy. This is an entirely novel scholarly contribution to the study of the director. The German and French States were not indifferent to the development of political theatre. A network of public theatres was thus developed in the inter-war period, and more significantly after the Second World War. The fifth chapter shows how State theatre policies establish its sources in the development of political theatre, and more specifically in the German theatre trade union movement (Volksbiihne) and the great directors at the end of the nineteenth-century. French political theatre was more influenced by playwrights and actors (Romain Rolland, Louise Michel, Louis Lumet, Emile Berny). French theatre policy was based primarily on theatre directors who decentralised their activities in France during both the inter-war period and the German occupation. After the Second World War, the government established, through directors, a strong network of public theatres. Directors became both the artistic director and the executive director of those institutionalised theatres. The institution was, however, seriously shaken by the social and political upheaval of 1968. It is the link between the State and the institution in which established directors were entangled that was challenged by the young emerging directors who rejected institutionalised responsibility in favour of the autonomy of the artist in the 1960s. This process is elucidated in chapter five. The final chapter defines the contemporary role of the director in contrasting thework of a number of significant young theatre practitioners in the 1960s such as Peter Brook, Ariane Mnouchkine, The Living Theater, Jerzy Grotowski, Augusto Boal, Eugenio Barba, all of whom decided early on to detach their companies from any form of public funding. This chapter also demonstrates how they promoted new forms of performance such as the performance of the self. First, these practitioners explored new performance spaces outside the traditional theatre building. Producing performances in a non-dedicated theatre place (warehouse, street, etc.) was a more frequent practice in the 1960s than before. However, the recent development of cybertheatre questions both the separation of the audience and the practitioners and the place of the director's role since the 1990s. Secondly, the role of the director has been multifaceted since the 1960s. On the one hand, those directors, despite all their different working methods, explored western and non-western acting techniques based on both personal input and collective creation. They challenged theatrical conventions of both the character and the process of making the performance. On the other hand, recent observations and studies distinguish the two main functions of the director, the acting coach and the scenographe, both having found new developments in cinema, television, and in various others events. Thirdly, the contemporary director challenges the performance of the text. In this sense, Antonin Artaud was a visionary. His theatre illustrates the need for the consideration of the totality of the text, as well as that of theatrical production. By contrasting the theories of Artaud, based on a non-dramatic form of theatre, with one of his plays (Le Jet de Sang), this chapter demonstrates how Artaud examined the process of making the performance as a performance. Live art and autobiographical performance, both taken as directing the se(f, reinforce this suggestion. Finally, since the 1990s, autobiographical performance or the performance of the self is a growing practical and theoretical perspective in both performance studies and psychology-related studies. This relates to the premise that each individual is making a representation (through memory, interpretation, etc.) of her/his own life (performativity). This last section explores the links between the place of the director in contemporary theatre and performers in autobiographical practices. The role of the traditional actor is challenged through non-identification of the character in the play, while performers (such as Chris Burden, Ron Athey, Orlan, Franko B, Sterlac) have, likewise, explored their own story/life as a performance. The thesis demonstrates the validity of the four parameters (performer, performance space, devising process, social event) defining a generic approach to the director. A generic perspective on the role of the director would encompass: a historical dimension relative to the reasons for and stages of the 'emergence' of the director; a socio-political analysis concerning the relationship between the director, her/his institutionalisation, and the political realm; and the relationship between performance theory, practice and the contemporary role of the director. Such a generic approach is a new departure in theatre research and might resonate in the study of other collaborative artistic practices.