View-based approaches to spatial representation in human vision

In an immersive virtual environment, observers fail to notice the expansion of a room around them and consequently make gross errors when comparing the size of objects. This result is difficult to explain if the visual system continuously generates a 3-D model of the scene based on known baseline information from interocular separation or proprioception as the observer walks. An alternative is that observers use view-based methods to guide their actions and to represent the spatial layout of the scene. In this case, they may have an expectation of the images they will receive but be insensitive to the rate at which images arrive as they walk. We describe the way in which the eye movement strategy of animals simplifies motion processing if their goal is to move towards a desired image and discuss dorsal and ventral stream processing of moving images in that context. Although many questions about view-based approaches to scene representation remain unanswered, the solutions are likely to be highly relevant to understanding biological 3-D vision

The Intergenerational Earnings and Income Mobility of Canadian

Our objective is to obtain an accurate estimate of the degree of intergenerational income mobility in Canada. We use income tax information on about 400,000 father-son pairs, and find intergenerational earnings elasticities to be about 0.2. Earnings mobility tends to be slightly greater than income mobility, but non- parametric techniques uncover significant non-linearities in both of these relationships. Intergenerational earnings mobilty is greater at the lower end of the income distribution than at the upper end, and displays an inverted V-shape elsewhere. Intergenerational income mobility follows roughly the same pattern, but is much lower at the top of the income distribution.Intergenerational Income Mobility, Income Distribution, Nonparametric regression

Bootstrapping spectral statistics in high dimensions

Statistics derived from the eigenvalues of sample covariance matrices are called spectral statistics, and they play a central role in multivariate testing. Although bootstrap methods are an established approach to approximating the laws of spectral statistics in low-dimensional problems, these methods are relatively unexplored in the high-dimensional setting. The aim of this paper is to focus on linear spectral statistics as a class of prototypes for developing a new bootstrap in high-dimensions --- and we refer to this method as the Spectral Bootstrap. In essence, the method originates from the parametric bootstrap, and is motivated by the notion that, in high dimensions, it is difficult to obtain a non-parametric approximation to the full data-generating distribution. From a practical standpoint, the method is easy to use, and allows the user to circumvent the difficulties of complex asymptotic formulas for linear spectral statistics. In addition to proving the consistency of the proposed method, we provide encouraging empirical results in a variety of settings. Lastly, and perhaps most interestingly, we show through simulations that the method can be applied successfully to statistics outside the class of linear spectral statistics, such as the largest sample eigenvalue and others.Comment: 42 page

Evidence against memorial facilitation and context-dependent memory effects through the chewing of gum

The experiment examined the prediction that chewing gum at learning and/or recall facilitated subsequent word recall. Chewing gum at learning significantly impaired recall, indicating that the chewing of gum has a detrimental impact upon initial word encoding. In addition, a context-dependent memory effect was reported for those participants who both learned and recalled in the absence of gum, however a context dependent effect was not found with chewing gum. The findings contradict previous research

Copolymers of methacrylic acid and itaconic acid derivatives as thermally crosslinkable electron resists

This thesis describes the preparation and lithographic evaluation of copolymers of methyl methacrylate, dimethyl itaconate and α - methyl styrene with derivatives of methacrylic acid or itaconic acid as thermally crosslinkable electron resists. A number of promising materials, including copolymers, terpolymers and mixtures of two types of copolymer have been identified, and have been demonstrated to be capable of sub 500nm resolution. Statistical copolymers have been found to show a general variation in resist properties with copolymer composition. This has been discussed in terms of the variation in the proportion of crosslinking groups present, and in changes in radiation sensitivity and solvent development behaviour with copolymer composition. It has been shown that the exposure dose required to first solubilise the resist can be very much less than that required for the development of high resolution resist features. Experimental results obtained in this work are compared to a theory originally published to describe the solubilisation of lignin from plant tissues, whereby gel degradation can be conceptually treated as the reverse of network formation

“Without Obscuring Deeper Truths:” Interpreting Slavery and Jefferson at Monticello

This thesis examines the paradigmatic shift in interpretation that occurred at Thomas Jefferson’s Monticello during the 1980s and 1990s. For decades, the Thomas Jefferson Memorial Foundation presented the site as a marvel of architecture, décor, as well as exemplifying Jefferson’s tranquil domestic life and intellectual talents. Beginning in the 1980s, the Foundation began to address slavery at the site. Chapter one introduction of slavery interpretation during this period. Early attempts to interpret slavery became intertwined with the Foundation’s positive portrayal of Jefferson before becoming more varied and provocative in the 1990s. Chapter two examines the parallel evolution in Jefferson scholarship, where biographers attempted to both address slavery and preserve their hagiographic vision of Jefferson. Chapter 3 explores an unintended consequence of the slavery interpretation: the reemergence of Jefferson’s political legacies as a thematic and tonal counterbalance to critical discussions about slavery. The inclusion of slavery in Monticello’s interpretation created a space for critical thought and provocative questions about the symbolism of Jefferson and the site. However, the presentation of Jefferson’s political legacies remained uncritical and congratulatory, showing the limits of Monticello’s transformation

Chewing gum and context-dependent memory: The independent roles of chewing gum and mint flavour

Two experiments independently investigated the basis of the chewing-gum induced context-dependent memory effect (Baker et al, 2004). At learning and/or recall participants either chewed flavourless gum (Experiment 1) or received mint-flavoured strips (Experiment 2). No context dependent memory effect was found with either flavourless gum or mint-flavoured strips, indicating that independently the contexts were insufficiently salient to induce the effect. This is found despite participants’ subjective ratings indicating a perceived change in state following administration of flavourless gum or mint-flavoured strips. Additionally, some preliminary evidence for a non-additive facilitative effect of receiving gum or flavour at either learning and/or recall is reported. The findings raise further concerns regarding the robustness of the previously reported context-dependent memory effect with chewing gum

Structure of the Human FANCL RING-Ube2T Complex Reveals Determinants of Cognate E3-E2 Selection

The combination of an E2 ubiquitin-conjugating enzyme with an E3 ubiquitin-ligase is essential for ubiquitin modification of a substrate. Moreover, the pairing dictates both the substrate choice and the modification type. The molecular details of generic E3-E2 interactions are well established. Nevertheless, the determinants of selective, specific E3-E2 recognition are not understood. There are ~40 E2s and ~600 E3s giving rise to a possible ~24,000 E3-E2 pairs. Using the Fanconi Anemia pathway exclusive E3-E2 pair, FANCL-Ube2T, we report the atomic structure of the FANCL RING-Ube2T complex, revealing a specific and extensive network of additional electrostatic and hydrophobic interactions. Furthermore, we show that these specific interactions are required for selection of Ube2T over other E2s by FANCL

Image and Virtue in Ambrose of Milan

This dissertation analyzes Ambrose of Milan’s trinitarian theology and doctrine of human action and argues that a visual logic—that works disclose nature—animates both. Ambrose’s trinitarian theology, on the one hand, trades in scriptural proofs that emphasize the tangible works (opera) of the Son as relevatory of his divinity and indicative of his shared, invisible power with the Father. While Ambrose differs from his Latin and Greek predecessors, he takes up controverted texts in his Christological reflection, many of which are borrowed from anti-monarchian and anti-homoian debates in the several generations prior. To show Ambrose’s consonance with the pre- and pro- Nicenes, I first investigate the common exegetical strands that occupy four Latins: Tertullian, Novatian of Rome, Hilary of Poitiers, and Marius Victorinus. In his own Christology, Ambrose uses many of the same debated scriptural passages as they did to foreground the importance of the Son’s works for revealing his shared divine power with the Father. However, Ambrose builds upon these exegetical strands, adding unique and unprecedented reflection that colors his theological anthropology and subsequent moral counsel. In particular, Ambrose adapts the trope of God as Painter, supported by Isaiah 49:16, when considering the moral significance of the image of God. While such a move might appear miniscule, I argue to the contrary. If the God who is known by and operates under the auspices of a visual logic paints the human soul, then the correlative action of the individual will follow a similar script. This similar script is plain in Ambrose’s doctrine of human action. Ambrose’s consistent emphasis on public Christian virtue is adapted largely from Roman exhortations to public virtue and married neatly to Ambrose’s pro-Nicene Christology. While the distinct character of human action is public, the signal content of Christian virtue has to do with its simplicity. Simplicity in word and deed not only serves as moral ideal, but does the double service of dismissing Ambrose’s most proximate doctrinal opponents, the homoians. I conclude that by connecting orthodoxy and virtue, Ambrose affords us a noteworthy contribution to fourth-century Christian theology