VictorJuiz/thesis huggingface dataset:
Interactions between the Woodwasp Sirex noctilio and Co-habiting Phloem- and Woodboring Beetles, and their Fungal Associates in southern Ontario

In its introduced southern hemisphere range, Sirex noctilio causes considerable mortality in non-native pine forests. In its native Eurasian range however, S. noctilio is of little concern perhaps due to interactions with a well-developed community of pine-inhabiting insects and their associated microorganisms. If such interactions occur, they may limit the woodwasp’s impact in its newly introduced range in North America. My research addresses two broad questions: 1) Does S. noctilio share its habitat with other insects and if so, with whom? 2) Is there evidence that co-habitants affect S. noctilio, and if so how might such interactions occur? Field studies undertaken to describe the woodwasp’s host-attack ecology in Pinus sylvestris showed S. noctilio activity occurred between mid-July and late August, and other phloem- and woodborers sometimes entered the tree after the woodwasp. Tree mortality occurred from two weeks to several months after initial woodwasp symptoms. Suppressed or intermediate trees, those with ≤ 25% residual foliage, or those with stem injury or previous woodwasp symptoms were most likely to have symptoms of woodwasp attack. A second field study conducted to identify associated insect species in S. noctilio-infested Pinus sp. showed the wasp was sometimes found alone, but usually shared the tree with other phloem- or woodboring insects, most commonly the curculionids Tomicus piniperda, Pissodes nemorensis and Ips grandicollis and the cerambycid Monochamus carolinensis. I found no indication that wasps were absent when beetles were present, but there was evidence that woodwasps were less abundant, but larger, when beetles were present. Experiments showed that indirect interactions can occur between the two insect groups via fungal associates of one or both. In the laboratory, the woodwasp symbiont was outcompeted by two beetle-associated fungi, Leptographium wingfieldii and Ophiostoma minus, over a range of temperatures. Under field conditions the woodwasp was able to detect and avoid ovipositing in P. sylvestris inoculated with L. wingfieldii, but its oviposition was unaffected by O. minus. My results show that insects co-habiting pine with S. noctilio have potential to exert a measure of biological control on the woodwasp and may help to limit its impact in North America.

Keywords: insect
fungus
community ecology
interactions
Advisor: Smith, Sandy
Groot, Peter de
Production Knowledge in the Recognition of Dysarthric Speech

Millions of individuals have acquired or have been born with neuro-motor conditions that limit the control of their muscles, including those that manipulate the articulators of the vocal tract. These conditions, collectively called dysarthria, result in speech that is very difficult to understand, despite being generally syntactically and semantically correct. This difficulty is not limited to human listeners, but also adversely affects the performance of traditional automatic speech recognition (ASR) systems, which in some cases can be completely unusable by the affected individual. This dissertation describes research into improving ASR for speakers with dysarthria by means of incorporated knowledge of their speech production. The document first introduces theoretical aspects of dysarthria and of speech production and outlines related work in these combined areas within ASR. It then describes the acquisition and analysis of the TORGO database of dysarthric articulatory motion and demonstrates several consistent behaviours among speakers in this database, including predictable pronunciation errors, for example. Articulatory data are then used to train augmented ASR systems that model the statistical relationships between vocal tract configurations and their acoustic consequences. I show that dynamic Bayesian networks augmented with instantaneous theoretical or empirical articulatory variables outperform even discriminative alternatives. This leads to work that incorporates a more rigid theory of speech production, i.e., task-dynamics, that models the high-level and long-term aspects of speech production. For this task, I devised an algorithm for estimating articulatory positions given only acoustics that significantly outperforms the state-of-the-art. Finally, I present ongoing work into the transformation and re-synthesis of dysarthric speech in order to make it more intelligible to human listeners. This research represents definitive progress towards the accommodation of dysarthric speech within modern speech recognition systems. However, there is much more research that remains to be undertaken and I conclude with some thoughts as to which paths we might now take.

Keywords: Dysarthria
Automatic speech recognition
Articulatory models
Advisor: Hirst, Graeme
Probing the Interstellar Medium and Massive Star Formation using Submillimeter Dust Emission

This thesis aims to improve our understanding of the early stages of massive star formation and of the physical properties of interstellar clouds. To achieve this, I have used submillimeter continuum dust emission data obtained by the Balloon-borne Large Aperture submillimeter Telescope (BLAST) in the first science flight in 2005, with a 2-m telescope operating simultaneously at 250, 350, and 500 micron. Unfortunately, BLAST produced images of about 3'3 resolution due to an uncharacterized optical problem. In Chapter~2, I discuss implementation of the Lucy-Richardson (L-R) method of deconvolution to restore BLAST images to near diffraction limited resolution. Its performance and convergence have been extensively analyzed through simulations and comparison of deconvolved images with available high-resolution maps. In Chapter~3, I study diverse phenomena in the Cygnus~X region associated with high mass star-formation. To interpret the BLAST emission more fully and place the compact sources in context, archival data cubes of 13CO line emission from KOSMA, MIPS images from the Spitzer Legacy Survey of this region, and 21-cm radio continuum emission from the Canadian Galactic Plane Survey have been used. Utilizing available ancillary multi-wavelength observations, the influence of OB stars and stellar clusters on Cygnus~X has been studied,revisiting the well-known DR HII regions and their surroundings in the light of submillimeter continuum dust emission and CO line emission. An effort has been made to assess the evolutionary sequence of the compact sources (spatial extent of about 1~pc) on the basis of L-M diagram and subsequently to relate this sequence to independent empirical evidence and theory. Using multi-resolution observations, evidence for hierarchical substructures within molecular clouds has been examined. Finally, in Chapter~4, a multi-wavelength power spectrum analysis of the large scale brightness fluctuations in the Galactic plane is presented. This analysis has been used to assess the level of cirrus noise which limits the detection of faint sources. A characteristic power law exponent of about -2.7 has been obtained for sub-regions of Aquila and Cygnus~X. The observed relative amplitudes of power spectra at different wavelengths have been related through a spectral energy distribution, thereby determining a characteristic temperature for the Galactic diffuse emission.

Keywords: astrophysics
massive star formation
Advisor: Martin, Peter
Ultrafast Active Plasmonics on Gold Films

Active plasmonics combines the manipulation of light on both sub-wavelength length and ultrashort time scales, a unique meld that holds promise for developments in many scientific fields. This thesis reports on a novel approach to ultrafast, all-optical control of grating-assisted excitation of surface plasmon polaritons based on opto-thermally modifying the optical properties of gold. In contrast to prior works, this approach results in plasmonic modulation on picosecond and even sub-picosecond time scales, and is compatible with modern, multi-GHz information processing technology. Finally, an analytic model is developed that allows for the rapid and accurate calculation of the coupling efficiency of beams with arbitrary spatial profile. First, the ultrafast dynamics of existing plasmonic coupling resonances, on gold films with grating overlayers, are studied with spectrally resolved pump-probe measurements. Irradiation of the metal by 700 fs, 775 nm laser pulses results in modulations of the plasmonic coupling efficiency of ~20% near the center, or ~60% off-center, of resonances centered between 540 nm and 700 nm. The modulations decay with a time constant of 770 +/- 70 fs. The experimental results are consistent with simulations based on the thermal-dynamics of the electron-lattice gold system, coupled with numerical modeling of light-grating interactions. Next, two 150 fs, 810 nm laser beams are interfered on the surface of a planar gold film, leading to an absorption/refraction grating in the metal. Optical pump-probe spectroscopy measurements of the first (-1) diffracted order in transmission identify plasmonic coupling resonances between 520 nm and 570 nm. The observed coupling efficiency is ~10^{-5}, and the launch window decays with a time constant of 620 +/- 100 fs. Lastly, a Green function-based analytic model is developed to describe grating assisted plasmonic coupling, culminating in a first-order differential equation with coefficients that have both clear physical significance as well as analytic forms. Comparison of this technique with standard numerical modeling methods shows that plasmonic coupling efficiencies in excess of 0.8 are predicted within an error of 15%. This model is used to study plasmonic excitation by finite-size beams, showing the spatial evolution of the intensity of both the surface plasmon polariton and the reflected beam.

Keywords: Surface Plasmon Polariton
Ultrafast
Advisor: Driel, Henry M. van
A Measurement of the Azimuthal Decorrelation in Di-jet Events in Proton-proton Collisions at ûs = 7 TeV at the Large Hadron Collider

A measurement of the azimuthal decorrelation in di-jet events in proton-proton collisions at √ s = 7 TeV is presented. Using 19.6 nb−1 of data collected in the ATLAS detector this measurement uses the angle (∆φ) in the transverse plane between the two leading pT jets to measure the normalized differential cross section 1 σtot dσ d(∆φ) . An unfolding correction is a applied to give a jet-level result. The unfolded spectrum is compared to the predictions of two Monte Carlo event generators: Pythia and Herwig++.

Keywords: azimuthal decorrelation
lhc
atlas
qcd
delta phi
Advisor: Krieger, Peter
The Effects of Polo-like Kinase 4 on Chromosomal Stability, Cell Migration and Tumourigenesis

Plk4 is the most divergent member of the family of polo like kinases (Plks). Plk4-/- embryos arrest at approximately day 7.5 p.c. but Plk4+/- mice are viable and fertile. However, 50% of Plk4+/- mice develop spontaneous tumours of the liver, lung and soft tissues by 2 years of age. Here I investigate the mechanisms that underlie Plk4-related tumourigenesis. Plk4+/- murine embryonic fibroblasts (MEFs) spontaneously become immortal in vitro with increasing passage number and are tumourigenic in vivo when injected into NOD SCID mice. Cytogenetic analysis showed that Plk4 deficient cells are chromosomally unstable with a large number of chromosomal aberrations and increased ploidy. These results demonstrate that early loss of a single Plk4 allele is sufficient to drive cell immortalization, chromosomal instability and tumourigenicity in vivo. In two independent expression array analyses, gene expression patterns that would decrease cell migration were overrepresented in Plk4+/- MEFs. A series of spreading and migration assays functionally validated these results, supporting the hypothesis that Plk4 regulates cell motility. Endogenous Plk4 localized to filopodia and lamellipodia in motile cells and to protrusions of spreading cells; the latter localization was transient and it disappeared by 4h after cell seeding, at which point Plk4 was located in the centrosomes, as typically observed in interphase cells. Transient transfection with Flag-Plk4 enhanced spreading and migration, as well as actin remodeling. Taken together, these data demonstrate temporal regulation of Plk4 in relation to the process of membrane remodeling, and a functional role for Plk4 in cell motility. Plk4 is haploinsufficient for tumour suppression in mice. Plk4 is located at human chromosome 4q28, a region often deleted in primary liver cancer specimens. Here I show that loss-of-heterozygosity (LOH) occurs at the Plk4 locus in ≈50% of human hepatocellular carcinomas (HCC) as well as in preneoplastic cirrhotic liver nodules. LOH at Plk4 is associated with reduced Plk4 expression in HCC tumours, but not with mutations in the remaining allele. These results implicate Plk4 as a potential haploinsufficient tumour suppressor in the genesis of human HCC. With continuing high rates of the predisposing conditions Hepatitis B and non-alcoholic steatohepatitis, and delayed diagnosis, HCC is a global health issue and carries a grave prognosis. A better understanding of genetic predisposition will help guide future screening programs.

Keywords: Polo-Like Kinase 4
Cancer
Advisor: Swallow, Carol
Aproximaciones Literarias a la Memoria, Historia e Identidad en la Literatura Contemporánea de Guinea Ecuatorial

Esta tesis examina cómo las narrativas de María Nsué Angüe, Joaquín Mbomio Bacheng, Donato Ndongo-Bidyogo, y Juan Tomás Ávila Laurel re-escriben la historia de Guinea Ecuatorial. Los autores articulan un discurso contestatario a las construcciones sociales afincadas por el discurso homogéneo colonialista. Los análisis textuales se realizan tomando en cuenta la vigencia cultural española en el discurso político nacional inmediato a la independencia del país en 1968. Las obras cuestionan la definición de la identidad guineana con respecto a la implementación de los valores culturales, históricos, lingüísticos, religiosos, y políticos en el territorio guineano. Las indagaciones, los rechazos, las condenas, y las rupturas que se analizan las representaciones literarias son posibles mediante el acercamiento teórico de la memoria. A partir de esta interacción discursiva literaria surgen nuevas interpretaciones que permiten entender la experiencia histórica del sujeto guineano.

Keywords: Equatorial Guinea
Memory
Trauma
History
Contemporary Literature
Identity
Advisor: Blackmore, Josiah
Beauty, To Kalon, and Its Relation to the Good in the Works of Plato

Despite the evident importance of beauty (τὸ καλόν) in Plato, the precise relation between beauty and goodness (τὸ ἀγαθόν) has yet to be specified. Part of the reason for this seems to be the belief that καλός should not be translated ‘beautiful,’ because it has a broader sense and application than our word ‘beautiful.’ A better translation, on this view, would be something like ‘fine.’ But it is difficult to see the difference between fineness and goodness, and it is perhaps for this reason that determining the relation between the two has not been felt an urgent task. In the first chapter we shall investigate the use of the Greek word καλός in some of the major authors prior to and contemporary with Plato in order to determine the strength of the evidence for translations of καλός other than ‘beautiful.’ It will be argued that the evidence for translations of καλός other than ‘beautiful’ is weak, and thus that the word should generally be translated ‘beautiful.’ When we turn to Plato’s understanding of τὸ καλόν, we find that he often seems to associate the concept closely with goodness, and yet there are also passages which suggest a difference between the two. Thus the first question to ask is whether beauty and goodness are at least coextensive for Plato? In the second chapter it will be argued that despite some apparent evidence to the contrary, he does seem to think they are coextensive. In the third chapter we argue that Plato identifies goodness and unity, and that the coextension of goodness and beauty is explained on the model of the necessary connection between certain forms, or immanent characters, in the Phaedo. But it does not follow from this that goodness and beauty are identical. In the fourth chapter we will argue that, though beauty and goodness are connected in concrete particulars, qua forms they are distinct, i.e., there are two separate forms, the form of the good (which is identical to the one) and the form of beauty. Finally, a theme which runs more or less throughout this work is that, contrary to what one might expect, Plato seems to discover what is good by asking what is beautiful. This may seem counterintuitive, because there are passages, like Republic 452d-e and 509b, where it seems that goodness determines or in a way causes beauty, but it seems that when trying to discover what is truly good, Plato always settles on what is beautiful. It may be agreed, even by those who disagree about what goodness is, that things like justice and courage are beautiful, and it is these that Plato always thinks constitute the human good.

Keywords: beauty
plato
Advisor: Gerson, Lloyd
Analyzing Tension and Drama in Beethoven’s First-movement Sonata Forms

Dramatic, in the sense of “highly intense,” is a quality we often associate with the music of Beethoven, but no theory has attempted to define drama in any systematic manner. This study therefore explores the idea by constructing a theory that distinguishes between dramatic and non-dramatic passages. At the core of the theory is the notion that drama is the result of several types of tension occurring simultaneously. Dramatic passages have a “High” tension level, whereas non-dramatic ones have a “Low” level. Individual tension types are divided into two categories: rhetorical and syntactical. Rhetorical tension types include such features as a loud dynamic, a fast rhythm, and a thick texture, which need no musical context to be expressed. By contrast, syntactical tension types include such features as chromaticism, metric irregularity, and phrase expansion, which always require a comparison of events to be expressed. Only tension types from the same category may combine to form drama. Because this study examines the relationships between drama and sonata form, the analysis of form is a key issue that receives a separate chapter and additional thought throughout. The methodology combines aspects of William E. Caplin’s theory of formal functions and James Hepokoski and Warren Darcy’s Sonata Theory, and is applied to all of Beethoven’s first-movement sonata forms, a total of eighty-seven movements. Each formal unit is analyzed as one of six dramatic “archetypes” that describe a basic outline of High and/or Low tension levels. These archetypes constitute the dramatic structure of the piece. Percentage frequencies of the archetypes were calculated for each formal unit in the movements as a whole, and as grouped by the categories of key, mode, genre, and style period. The greatest distinctions in dramatic structure occur among the three style periods of early, middle, and late, the early works showing a sectional approach with contrasting tension between phrases and the middle to late works gradually becoming more continuous, maintaining the same tension levels between units. A concluding analysis of Beethoven’s String Trio, op. 3, demonstrates the theory’s ability to enrich the interpretation of an individual work.

Keywords: Beethoven
tension
drama
sonata form
analysis
style
Advisor: McClelland, Ryan
From Collectives to Connectives: Italian Media Activism and the Repurposing of the Social

The dissertation develops the concept of repurposing as a means for thinking with activists and the issues they confront. It moves alongside pirate television collective insu^tv as they draw on a variety of histories, traditions and technological resources for their practices. Repurposing functions on multiple levels and at multiple scales, from the recycling of materials and spaces to the harnessing and relaying of encounters and events within an ever-expanding field of social relations. When seen as a way of connecting activist groups and communities, the repurposing of media contributes to strengthening an often fragmented and conflicted activist field. Indeed, insu^tv’s use of information and technology brings to the fore the value of media activism for the creation of social assemblages in which the “media” literally mediates between individuals and among individuals and their environment, instituting and developing an ontogenetic relation (Simondon, 1989). Yet, rather than simply making sense of insu^tv’s practices, the concept of repurposing also provokes a discussion regarding the ethics of connection. For insu^tv, this connective ethics can be understood as a set of rules and principles that facilitate the evaluation of actions, communication, and thought according to an immanent mode of collective existence (Deleuze, 1988; Simondon, 1989). For the author, herself a member of insu^tv and an academic researcher, this immanent position helps challenge traditional models of knowing and envisioning social change and instead proposes alternatives that attend to the singularity and relation among new political movements, and to the political potential of research methods that focus on process and fold activism into academia. The methodology is inspired by the militant research methods of the Italian Autonomia movement (conricerca or inchiesta), as developed and performed by activists themselves. While attending to the complexity of social struggles, the concept of repurposing enables an approach to research and experimentation as modes of sociability, where these modes are themselves repurposed through an ethics of connection. This line informs the relation between ethics and subjectivation, as well as between ethics and micropolitics, facilitating the emergence of new modes of political action through the repurposing of the social field itself.

Keywords: grassroots media
activism
co-research
Telestreet
differential accumulation
Autonomia
Advisor: Heller, Monica