18 research outputs found

    Vectorisation of male supremac(h)ist ideologies in high-impact narratives and sociopolitical statism in western contemporary patriarchies

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    The present thesis dissertation, oriented at the fulfilment of the requirements for the obtention of the Philosophy Doctor, aims provide an intensive analysis on the deployment of traditional and contemporary narrative formats, in the context of the patriarchal establishments which have governed the Western world since early foundational civilisations, for the endurance of their supremac(h)ist organisation principles through the creation and maintenance of a conceptually recreated gender breach. The appropriate obtention of relevant data, for the surveyal of the potential encoding of gender unequal ideological concerns, as oriented to the alterity portrayal of the male and the female with socio-political stratification purposes, from the analysis of such a wide variety of narrative formats entails the implementation of diverse, text-specific, methodological guidelines. The technology in the contemporary world has imposed the inevitable presence of penetrating audiovisual ideological narratives with a massive outreach. Such would be the case of television, whose brief, but precise, advertisement narrations are studied to intergenerationally perpetuate the patriarchal task distribution that displaces women to the private sphere for the performance of kitchen and cleansing duties in a world were women cannot be denied to work and efforts for conciliation are necessary, as exhibited in the analysed costumbrist spots by major and highly consumer-endorsed brands ‘Natillas La Lechera’ and ‘La Cocinera’, or ‘Lejía Conejo’ bleach, ‘Vileda Windomatic’ squeege and ‘Philips Perfect Care’. As opposed to television advertising, other audiovisual formats, such as animation, do not intend to depict spectators’ daily life, but to present easy-to-embrace characters, who are studied to hold a powerful faculty to channelise narrative-controlled feelings and ideas. Such a factor would justify the eligibility of The Simpsons, as the longest scripted show in TV history and the most popular family in UK, over the royal family. In ‘The Diatribe of a Mad Housewife’, the female incorporation to the public sphere of professional life, which materialises in female writing, is deceitfully conceived as a source of misandry and conflict between the male figures of reference. Another audiovisual narrative format for male chauvinist ideologisation, video games, would interestingly resort to the immersion of fictional worlds governed by representational rules tacitly accepted by players when interacting with such influential major entertainment products, so the player-avatar identification facilitates the extrapolation of the gender-based in-game representations to the players’ external reality. Specifically, top-sales Resident Evil 4 (2005) and Bioshock Infinite (2013) present their respective female protagonists, Ashley Graham and Elisabeth Comstock, as passive entities to possess and custody in the private sphere, being both the characters the unfortunate threat to the socio-political stability of the status quo when the private custody decays and their control is usurped by male figures who move them to other public or private spaces. As observed in Resident Evil 4, the reversibility of such a systemic unbalance may be feasible when the damsel in danger is rescued from the private captivity setting and the initial custody by the male president of the United States and head of the free patriarchal world is restored. However, the male custody of Elisabeth Comstock in Bioshock Infinite’s public sphere, which implies her presence outside the house prophylactic confinement, is contrastively portrayed as the catalyser of the unleash of female uncontrolled powers and the inevitable destruction of the malecreated civilisation. The first five games in Pokémon saga offer a peaceful alternative to Resident Evil 4 and Bioshock Infinite, where gender alterity is imposed by the necessary-to-progress interaction of the player with male and female flat stereotypical characters, and the peaceful coexistence of humans and monsters is guaranteed by a hierarchised power apparatus with a minimal female representation. On the contrary, contemporary written formats, along with the atemporal urban legend and news, are also examined to complement the holistic contribution performed by narratives for the creation of a multiplatform supremac(h)ist ideological apparatus. Thus, wide-outreach social networking interactions may be contemplated to resort to hoaxes, pseudo-informative narratives, for the fostering of gender-biased conceptions which justify the organisation of the community around the male figure. Specifically, Twitter is analysed to have been utilised by Spanish (ultra)right political forces to summon the population’s fear to massive concentrations in early COVID-19 crisis to depict Spanish 8M feminist activism and overtly feminist first-order female politicians as peril for the wellbeing of the community, which prioritises their ambitions to individuals’ health and integrity. In order to filter and retrieve the tweets to explore, term (8M, 8-M), chronological (March 6th – June 21st, 2020) and geolocation (Spain) Boolean operators have been implemented in Twitter internal browser. Boolean operators may also prove relevant for the discovery of news as a written narrative genre actively contaminated by writers’ ideological communicative intentions during text elaboration and design, as observed in the ideological justification and ‘laundering’ of the toxic model of possessive masculinity exhibited upon Will Smith’s aggressive restitution of the woman-channelised family name staining at 2022 Academy Awards. To these regards, the filtered journalistic reports on Smith’s assault on Chris Rock upon Jada Pinkett’s alopecia joke, in Spanish, English and Portuguese, highlight Pinkett’s passivity in favour of the male participants’ interventions, who are to impose offence on the defenceless woman, in the case of Rock, and deliver medieval-like justice, as providentially assigned by the Catholic divinity, for the effective exercise of the custody of the damsel in danger, as incarnated by Smith. In this context, contemporary broadcasting platforms reveal as powerful vectors of influencer-based toxic masculinities. The last of the written genres examined befits those high impact viral accounts, with adaptative contextual flexibility to enhance its relevance for the narratee, a sense of veracity and a cautionary ending which exhort narratees to vectorise the subliminally ideological precepts encoded in the story ‘DNA’. These atemporal narratives, extracted from Spanish and English language Ortí and Sampere (2017), Camacho (2005, 2007), Brown & Flynn (2003) and Brunvald’s (1999) anthologies are filtered to obtain urban legends which depict women ‘in action’ under no male custody, as in Camacho’s (2007) “Secado Rápido”, a story at the crossroads of gender and Elder age inferiority in the private sphere, where an unsupervised widow kills an innocent puppy while arrogantly trying to microwave-dry it after an unplanned bath; Brown and Flynn’s (1999) “Chain reaction”, where an uncivil, yet irrelevant, woman’s behaviour in a public transport space causes a massive disaster which redounds in the destruction of the male-created urban skyline; or Hayes’ (2013), where the female ambition’s to trespass women’s patriarchal limitations lead her to reach the top of the Catholic Church under the disguise of John Anglicus, in early 13th century, but meets the capital penalty when misguided by her lust and her subsequently unexpected public labor during a religious service in the surroundings of Rome’s colosseum and St. Clement’s church.La presente tesis doctoral, que está orientada a la satisfacción de los requisitos para la obtención del título de doctor en la rama de lenguas y culturas, pretende llevar a cabo un análisis intensivo de la utilización de formatos narrativos tradicionales y contemporáneos, en el contexto de los statu quo patriarcales que han gobernado el mundo occidental desde los albores de sus civilizaciones fundacionales, con el objeto de perdurar sus principios de organización ‘supremac(h)istas’ por medio de la creación y mantenimiento de una brecha de género de origen conceptual. La obtención adecuada de información relevante sobre la posible existencia de codificaciones ideológicas en base a la desigualdad de género, que estarían dirigidos a una descripción altérica de la mujer y el hombre para la estratificación sociopolítica, en tan amplia variedad de formatos narrativos, requiere la implementación de líneas metodológicas diversas y adaptadas al formato textual correspondiente. Las prestaciones tecnológicas del mundo contemporáneo han impuesto la presencia ineludible de narrativas ideológicas audiovisuales de largo alcance. Este sería el caso de la televisión y sus cortas narrativas publicitarias, que, aunque cortas pero precisas, contribuyen a la perpetuación intergeneracional de la distribución de tareas patriarcal, que desplazaría a la mujer a la esfera privada para la satisfacción de obligaciones, en lo que a la cocina y a la higienización del hogar se refiere, en un mundo en el que no se puede alienar el derecho a la mujer a trabajar y que impone un esfuerzo extra para la conciliación familiar, como se observa en los anuncios, de corte costumbrista, de productos de marcas punteras como ‘Natillas La Lechera’, ‘La Cocinera, ‘Lejía Conejo’, ‘Vileda Windomatic’ o ‘Philips Perfect Care’. Al contrario que en el caso de la publicidad televisiva, otros formatos audiovisuales, como la animación, no persiguen retratar la vida diaria del espectador, sino ofrecer personajes con los que simpatizar, dada su probada valía para la canalización de ideas y emociones en las narrativas en las que se enmarcan. Este factor justifica la elección de Los Simpsons, que se erigen como el espectáculo guionizado de mayor duración en la historia de la televisión, así como la familia más popular en Reino Unido, incluso por encima de la familia real del país. En ‘Diatriba de una ama de casa loca’, la incorporación de la mujer a la vida profesional de la esfera pública, que en el caso de Marge se materializa en la escritura femenina, se concibe, no exenta de engaño, como una fuente de misandria y conflicto entre las figuras masculinas de referencia en el entorno de social de Marge. Otro formato narrativo audiovisual de ideologización supremac(h)ista tendría su seno en los videojuegos, que ofrecen a los jugadores una experiencia inmersiva en la que, como fruto de la interacción con estos productos de entretenimiento de gran influencia, los jugadores aceptan tácitamente las reglas representacionales y operativas que gobiernan el mundo ficticio del juego. En particular, los títulos superventas Resident Evil 4 (2005) y Bioshock Infinite (2013), muestran a sus protagonistas femeninos respectivos, Ashley Graham and Elisabeth Comstock, como sujetos pasivos a poseer y custodiar en la esfera privada, suponiendo ambos personajes una amenaza para la estabilidad del statu quo cuando la custodia privada inicial decae y su control es apropiado indebidamente por otras figuras masculinas, que ejercerán una custodia forzosa de la mujer cautiva en otros contextos públicos y privados. Como se puede observar en Resident Evil 4¸el desequilibrio sistémico causado por dicho ‘traspaso’ solo reviste reversibilidad cuando se rescata a la ‘damisela en apuros’ del escenario privado donde se mantiene cautiva y se restaura la custodia inicial, a cargo del presidente de los Estados Unidos y líder del mundo patriarcal libre. Por el contrario, la custodia masculina de Elisabeth Comstock en la esfera pública de Bioshock Infinite, que implica inherentemente la presencia de la mujer fuera de su confinamiento profiláctico entre las cuatro paredes del hogar, se conceptualiza como el catalizador de la liberación de los poderes descontrolados de la misma y la destrucción inevitable de la civilización creada por la mano del hombre. Por otro lado, los cinco primeros títulos de la saga Pokémon ofrecen una alternativa pacífica al mundo ficticio de Resident Evil 4 y Bioshock Infinite, donde la interacción del jugador con personajes masculinos y femeninos estereotípicos y planos se impone como una necesidad para el progreso de los jugadores en la narrativa, y la convivencia pacífica entre seres humanos y monstruos viene de la mano de un aparato de poder jerarquizado en el que la presencia de la mujer es mínima. Por otro lado, los formatos escritos contemporáneos, junto con otros formatos atemporales como la noticia o la leyenda urbana, también son objeto de análisis, de cara al descubrimiento de la contribución holística de narrativas diversas a la creación de un aparato ideológico supremac(h)ista multiplataforma. En este contexto, se examina la manera en la que las interacciones en redes sociales de amplio alcance recurren a los bulos, narrativas pseudo-informativas, para la promoción de concepciones basadas en la desigualdad de género, que vendrían a justificar la organización sociopolítica de la comunidad en torno a la figura del hombre. En particular, se analiza el uso de Twitter, por parte de fuerzas de la (ultra)derecha política española, para avivar el miedo de la población general a las concentraciones masificadas en los albores de la crisis sanitaria de la COVID-19 y retratar, así, al activismo feminista español en torno al 8M, y a las políticas de primer orden que lo encabezan, como un peligro para el bienestar de la comunidad que priorizaría sus ambiciones a la salud e integridad de los ciudadanos. Para la recuperación y subsiguiente filtrado de los tuits a estudiar, se implementan los operadores booleanos terminológicos (8M, 8-M), cronológicos (del 6 de marzo al 21 de junio de 2020) y de geolocalización (España) en el buscador interno de Twitter. La pertinencia de los operadores Booleanos para el estudio de la noticia, como género narrativo que adolece de una contaminación por parte de las intenciones comunicativas ideológicas de sus escritores, durante el proceso de elaboración textual, se puede observar en la justificación ideológica y el ‘blanqueamiento’ del modelo de masculinidad tóxica exhibida por Will Smith en la restitución agresiva de la honra familiar, previamente violada por medio de la explotación de la mujer del núcleo familiar como instrumento para ello. En relación a esto, los relatos periodísticos filtrados en español, inglés y portugués destacan la pasividad de Pinkett en favor de la intervención de los intervinientes masculinos, quienes imponen su ofensa verbal sobre la mujer indefensa, en el caso de Rock, e imparten una justicia cuasi-medieval, de acuerdo a los designios providenciales de la divinidad católica, para el ejercicio de la custodia de la ‘damisela en apuros’, en el caso de Smith. En este contexto, las plataformas de retransmisión de contenidos contemporáneas se erigen como vectores poderosos de las masculinidades tóxicas exhibidas por las figuras influyentes antes mencionadas. El último de los géneros escritos explorados en la presente tesis correspondería a aquellos relatos virales de alto impacto, que destacarían por su flexibilidad contextual adaptativa al público meta, la sensación de veracidad que recrean y su final precautorio, factores que contribuirían, de forma holística, a la vectorización de los preceptos ideológicos imbricados subliminalmente en el ‘ADN’ de la narración. Estas narrativas atemporales, que han sido exploradas en las antologías en lengua castellana e inglesa de Ortí y Sampere (2017), Camacho (2005, 2007), Brown y Flynn (2003) y Brunvald (1999), han sido sometidas, con posterioridad, a su filtrado para la obtención de leyendas urbanas que crean un retrato distorsionado de la mujer ‘en acción’, lejos de la custodia masculina, como sería el caso de “Secado Rápido” (Camacho, 2007), una historia que entremezcla género y edadismo, como factores clave en la inferioridad del individuo, en la que una viuda sin supervisión acaba con la vida de un cachorro de perro al intentar, en un alarde de inteligencia arrogante, secarlo en el microondas tras un baño que no estaba en los planes de la ‘abuelita’. Así mismo, en la leyenda urbana de título “Chain Reaction” (Brown and Flynn, 1999), el comportamiento tan inadecuado como inocuo de una mujer poco cívica en el espacio público del transporte colectivo origina la devastación del paisaje urbano civilizado creado por el patriarcado. Por último, también es objeto de análisis la leyenda urbana de Hayes (2013), en la que la ambición femenina lleva a una mujer a traspasar las limitaciones previstas por el patriarcado para su género y alcanzar así, a principios del siglo XIII y bajo la identidad de John Anglicus, la cima de la jerarquía católica, siendo presa de su lujuria, que asombrará a los allí presentes con un inesperado parto durante una procesión religiosa en las cercanías del Coliseo Romano y la iglesia de San Clemente, y su posterior ejecución, como único sino de la mujer que invade los espacios reservados para el hombre

    The Cryptographic Imagination

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    Originally published in 1996. In The Cryptographic Imagination, Shawn Rosenheim uses the writings of Edgar Allan Poe to pose a set of questions pertaining to literary genre, cultural modernity, and technology. Rosenheim argues that Poe's cryptographic writing—his essays on cryptography and the short stories that grew out of them—requires that we rethink the relation of poststructural criticism to Poe's texts and, more generally, reconsider the relation of literature to communication. Cryptography serves not only as a template for the language, character, and themes of much of Poe's late fiction (including his creation, the detective story) but also as a "secret history" of literary modernity itself. "Both postwar fiction and literary criticism," the author writes, "are deeply indebted to the rise of cryptography in World War II." Still more surprising, in Rosenheim's view, Poe is not merely a source for such literary instances of cryptography as the codes in Conan Doyle's "The Dancing-Men" or in Jules Verne, but, through his effect on real cryptographers, Poe's writing influenced the outcome of World War II and the development of the Cold War. However unlikely such ideas sound, The Cryptographic Imagination offers compelling evidence that Poe's cryptographic writing clarifies one important avenue by which the twentieth century called itself into being. "The strength of Rosenheim's work extends to a revisionistic understanding of the entirety of literary history (as a repression of cryptography) and then, in a breathtaking shift of register, interlinks Poe's exercises in cryptography with the hyperreality of the CIA, the Cold War, and the Internet. What enables this extensive range of applications is the stipulated tension Rosenheim discerns in the relationship between the forms of the literary imagination and the condition of its mode of production. Cryptography, in this account, names the technology of literary production—the diacritical relationship between decoding and encoding—that the literary imagination dissimulates as hieroglyphics—the hermeneutic relationship between a sign and its content."—Donald E. Pease, Dartmouth Colleg

    DNA Computing: Modelling in Formal Languages and Combinatorics on Words, and Complexity Estimation

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    DNA computing, an essential area of unconventional computing research, encodes problems using DNA molecules and solves them using biological processes. This thesis contributes to the theoretical research in DNA computing by modelling biological processes as computations and by studying formal language and combinatorics on words concepts motivated by DNA processes. It also contributes to the experimental research in DNA computing by a scaling comparison between DNA computing and other models of computation. First, for theoretical DNA computing research, we propose a new word operation inspired by a DNA wet lab protocol called cross-pairing polymerase chain reaction (XPCR). We define and study a word operation called word blending that models and generalizes an unexpected outcome of XPCR. The input words are uwx and ywv that share a non-empty overlap w, and the output is the word uwv. Closure properties of the Chomsky families of languages under this operation and its iterated version, the existence of a solution to equations involving this operation, and its state complexity are studied. To follow the XPCR experimental requirement closely, a new word operation called conjugate word blending is defined, where the subwords x and y are required to be identical. Closure properties of the Chomsky families of languages under this operation and the XPCR experiments that motivate and implement it are presented. Second, we generalize the sequence of Fibonacci words inspired by biological concepts on DNA. The sequence of Fibonacci words is an infinite sequence of words obtained from two initial letters f(1) = a and f(2)= b, by the recursive definition f(n+2) = f(n+1)*f(n), for all positive integers n, where * denotes word concatenation. After we propose a unified terminology for different types of Fibonacci words and corresponding results in the extensive literature on the topic, we define and explore involutive Fibonacci words motivated by ideas stemming from theoretical studies of DNA computing. The relationship between different involutive Fibonacci words and their borderedness and primitivity are studied. Third, we analyze the practicability of DNA computing experiments since DNA computing and other unconventional computing methods that solve computationally challenging problems often have the limitation that the space of potential solutions grows exponentially with their sizes. For such problems, DNA computing algorithms may achieve a linear time complexity with an exponential space complexity as a trade-off. Using the subset sum problem as the benchmark problem, we present a scaling comparison of the DNA computing (DNA-C) approach with the network biocomputing (NB-C) and the electronic computing (E-C) approaches, where the volume, computing time, and energy required, relative to the input size, are compared. Our analysis shows that E-C uses a tiny volume compared to that required by DNA-C and NB-C, at the cost of the E-C computing time being outperformed first by DNA-C and then by NB-C. In addition, NB-C appears to be more energy efficient than DNA-C for some input sets, and E-C is always an order of magnitude less energy efficient than DNA-C

    Theoretical and Practical Aspects Related to the Avoidability of Patterns in Words

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    This thesis concerns repetitive structures in words. More precisely, it contributes to studying appearance and absence of such repetitions in words. In the first and major part of this thesis, we study avoidability of unary patterns with permutations. The second part of this thesis deals with modeling and solving several avoidability problems as constraint satisfaction problems, using the framework of MiniZinc. Solving avoidability problems like the one mentioned in the past paragraph required, the construction, via a computer program, of a very long word that does not contain any word that matches a given pattern. This gave us the idea of using SAT solvers. Representing the problem-based SAT solvers seemed to be a standardised, and usually very optimised approach to formulate and solve the well-known avoidability problems like avoidability of formulas with reversal and avoidability of patterns in the abelian sense too. The final part is concerned with a variation on a classical avoidance problem from combinatorics on words. Considering the concatenation of i different factors of the word w, pexp_i(w) is the supremum of powers that can be constructed by concatenation of such factors, and RTi(k) is then the infimum of pexp_i(w). Again, by checking infinite ternary words that satisfy some properties, we calculate the value RT_i(3) for even and odd values of i

    Word Blending and Other Formal Models of Bio-operations

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    As part of ongoing efforts to view biological processes as computations, several formal models of DNA-based processes have been proposed and studied in the formal language literature. In this thesis, we survey some classical formal language word and language operations, as well as several bio-operations, and we propose a new operation inspired by a DNA recombination lab protocol known as Cross-pairing Polymerase Chain Reaction, or XPCR. More precisely, we define and study a word operation called word blending which models a special case of XPCR, where two words x w p and q w y sharing a non-empty overlap part w generate the word x w y. Properties of word blending that we study include closure properties of the Chomsky families of languages under this operation and its iterated version, existence of solution to equations involving this operation, and its state complexity

    A Study of Pseudo-Periodic and Pseudo-Bordered Words for Functions Beyond Identity and Involution

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    Periodicity, primitivity and borderedness are some of the fundamental notions in combinatorics on words. Motivated by the Watson-Crick complementarity of DNA strands wherein a word (strand) over the DNA alphabet \{A, G, C, T\} and its Watson-Crick complement are informationally ``identical , these notions have been extended to consider pseudo-periodicity and pseudo-borderedness obtained by replacing the ``identity function with ``pseudo-identity functions (antimorphic involution in case of Watson-Crick complementarity). For a given alphabet Σ\Sigma, an antimorphic involution θ\theta is an antimorphism, i.e., θ(uv)=θ(v)θ(u)\theta(uv)=\theta(v) \theta(u) for all u,vΣu,v \in \Sigma^{*} and an involution, i.e., θ(θ(u))=u\theta(\theta(u))=u for all uΣu \in \Sigma^{*}. In this thesis, we continue the study of pseudo-periodic and pseudo-bordered words for pseudo-identity functions including involutions. To start with, we propose a binary word operation, θ\theta-catenation, that generates θ\theta-powers (pseudo-powers) of a word for any morphic or antimorphic involution θ\theta. We investigate various properties of this operation including closure properties of various classes of languages under it, and its connection with the previously defined notion of θ\theta-primitive words. A non-empty word uu is said to be θ\theta-bordered if there exists a non-empty word vv which is a prefix of uu while θ(v)\theta(v) is a suffix of uu. We investigate the properties of θ\theta-bordered (pseudo-bordered) and θ\theta-unbordered (pseudo-unbordered) words for pseudo-identity functions θ\theta with the property that θ\theta is either a morphism or an antimorphism with θn=I\theta^{n}=I, for a given n2n \geq 2, or θ\theta is a literal morphism or an antimorphism. Lastly, we initiate a new line of study by exploring the disjunctivity properties of sets of pseudo-bordered and pseudo-unbordered words and some other related languages for various pseudo-identity functions. In particular, we consider such properties for morphic involutions θ\theta and prove that, for any i2i \geq 2, the set of all words with exactly ii θ\theta-borders is disjunctive (under certain conditions)

    Network Narrative: Prose Narrative Fiction and Participatory Cultural Production in Digital Information and Communication Networks

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    In this study of prose narrative created explicitly for participatory network communications environments I argue that network narratives constitute an important, born-networked form of literary and cultural expression. In the first half of the study I situate network narratives within a rich, dynamic process of reciprocity and codependence between the technological, material and formal properties of communication media on the one hand, and the uses of these media in cultural practices and forms of expression on the other. I point out how the medial and cultural flows that characterize contemporary network culture promote a codependent relation between narrative and information. This relation supports literary cultural expressions that invoke everyday communication practices increasingly shaped by mobile, networked computing devices. In the second half of this study, I extend theoretical work in the field of electronic literature and digital media to propose a set of four characteristics through which network narratives may be understood as distinct modes of networked, literary cultural expression. Network narratives, I suggest, are multimodal, distributed, participatory, and emergent. These attributes are present in distinct ways, within distinct topological layers of the narratives: in the story, discourse, and character networks of the narrative structure; in the formal and navigational structures; and in the participatory circuits of production, circulation and consumption. Attending to these topological layers and their interrelationships by using concepts derived from graph theory and network analysis offers a methodology that links the particular, closely read attributes and content of network narratives to a more distant understanding of changing patterns in broader, networked cultural production. Finally, I offer readings of five examples of network narratives. These include Kate Pullinger and Chris Joseph’s Flight Paths, Penguin Books and De Montfort University’s collaborative project A Million Penguins, the Apple iOS application The Silent History, Tim Burton’s collaboration with TIFF, BurtonStory, and a project by NFB Interactive, Out My Window. Each of these works incorporates user participation into its production circuits using different strategies, each with different implications for narrative and navigational structures. I conclude by describing these distinct strategies as additive participation – participation that becomes embedded within the work itself – and delineating different approaches that are employed independently or in combination by the authors and producers

    Formal models of the extension activity of DNA polymerase enzymes

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    The study of formal language operations inspired by enzymatic actions on DNA is part of ongoing efforts to provide a formal framework and rigorous treatment of DNA-based information and DNA-based computation. Other studies along these lines include theoretical explorations of splicing systems, insertion-deletion systems, substitution, hairpin extension, hairpin reduction, superposition, overlapping concatenation, conditional concatenation, contextual intra- and intermolecular recombinations, as well as template-guided recombination. First, a formal language operation is proposed and investigated, inspired by the naturally occurring phenomenon of DNA primer extension by a DNA-template-directed DNA polymerase enzyme. Given two DNA strings u and v, where the shorter string v (called the primer) is Watson-Crick complementary and can thus bind to a substring of the longer string u (called the template) the result of the primer extension is a DNA string that is complementary to a suffix of the template which starts at the binding position of the primer. The operation of DNA primer extension can be abstracted as a binary operation on two formal languages: a template language L1 and a primer language L2. This language operation is called L1-directed extension of L2 and the closure properties of various language classes, including the classes in the Chomsky hierarchy, are studied under directed extension. Furthermore, the question of finding necessary and sufficient conditions for a given language of target strings to be generated from a given template language when the primer language is unknown is answered. The canonic inverse of directed extension is used in order to obtain the optimal solution (the minimal primer language) to this question. The second research project investigates properties of the binary string and language operation overlap assembly as defined by Csuhaj-Varju, Petre and Vaszil as a formal model of the linear self-assembly of DNA strands: The overlap assembly of two strings, xy and yz, which share an overlap y, results in the string xyz. In this context, we investigate overlap assembly and its properties: closure properties of various language families under this operation, and related decision problems. A theoretical analysis of the possible use of iterated overlap assembly to generate combinatorial DNA libraries is also given. The third research project continues the exploration of the properties of the overlap assembly operation by investigating closure properties of various language classes under iterated overlap assembly, and the decidability of the completeness of a language. The problem of deciding whether a given string is terminal with respect to a language, and the problem of deciding if a given language can be generated by an overlap assembly operation of two other given languages are also investigated
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