Effects of Momentum Conservation and Flow on Angular Correlations at RHIC

Correlations of azimuthal angles observed at RHIC have gained great attention due to the prospect of identifying fluctuations of parity-odd regions in the field sector of QCD. Whereas the observable of interest related to parity fluctuations involves subtracting opposite-sign from same-sign correlations, the STAR collaboration reported the same-sign and opposite-sign correlations separately. It is shown here how momentum conservation combined with collective elliptic flow contributes significantly to this class of correlations, though not to the difference between the opposite- and same-sign observables. The effects are modeled with a crude simulation of a pion gas. Though the simulation reproduces the scale of the correlation, the centrality dependence is found to be sufficiently different in character to suggest additional considerations beyond those present in the pion gas simulation presented here.Comment: 13 papges, 2 figure

Complementary Companion Behavior in Video Games

Companion characters in are present in many video games across genres, serving the role of the player\u27s partner. Their goal is to support the player\u27s strategy and to immerse the player by providing a believable companion. These companions often only perform rigidly scripted actions and fail to adapt to an individual player\u27s play-style, detracting from their usefulness. Behavior like this can also become frustrating to the player if the companions become more of a hindrance than they are a benefit. Other work, including this project\u27s precursor, focused on building companions that mimic the player. These strategies customize the companion\u27s actions to each player, but are limited. In the same context, an ideal companion would help further the player\u27s strategy by finding complementary actions rather than blind emulation. We propose a game-development framework that adds complementary (rather than mimicking) companions to a video game. For the purposes of this framework a complementary action is defined as any that furthers the player\u27s strategy both in the immediate future as well as in the long-term. This is determined through a combination of both player-action and game-state prediction processes, while allowing the companion to experiment with actions the player hasn\u27t tried. We used a new method to determine the location of companion actions based on a dynamic set of regions customized to the individual player. A user study of game-development students showed promising results, with a seventeen out of twenty-five participants reacting positively to the companion behavior, and nineteen saying that they would consider using the framework in future games

Discussion of: A statistical analysis of multiple temperature proxies: Are reconstructions of surface temperatures over the last 1000 years reliable?

Discussion of "A statistical analysis of multiple temperature proxies: Are reconstructions of surface temperatures over the last 1000 years reliable?" by B.B. McShane and A.J. Wyner [arXiv:1104.4002]Comment: Published in at http://dx.doi.org/10.1214/10-AOAS398F the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

The verse-epistles of Robert Burns : a critical study

From the introduction: So vast is the body of published work on Burns that one must justify yet another study of the poet. From 1786 to the present, his life and poetry have always had popular appeal. In his lifetime, he was an object of attention to all classes of society, from Ayrshire peasants to the habitue of Edinburgh drawing-roans, and detractors, idolaters, and disinterested parties have continued to scrutinize his achievements and failings. Popular attention has never wavered. In the nineteenth century especially, many and varied editions of Burns's poetry were published to satisfy this curiosity. Some were lavish, some cheap; some accurate, others, wildly imaginative. Nor has this demand noticeably slackened in the present century. Not a year passes without some book or pamphlet, albeit ephemeral, being published on Burns. To the scholarly mind, "popular", when applied to Burns studies, usually implies superficiality and this assumption all too often proves correct. It can hardly be said that the best minds of each age since Burns's death have considered him worthy of their critical attention in the way that Shakespeare, or Dante, or Milton have engaged scholars, editors, and publishers in succeeding generations. Byron, Coleridge, Hazlitt, Emerson, Carlyle, and Mac=armid have commented on Burns, and in the nineteenth century important and durable editorial work was undertaken. Nevertheless, it remains true that it was not until the twentieth century, and then only in bursts, that there developed a scholarly, academic interest to match the popular enthusiasm for Robert Burns

Examining the Roles of Thalamocortical and Frontoparietal Circuitry for Working Memory in the Rat

Working memory (WM) is the cognitive capacity for short-term maintenance and manipulation of stimuli and goals for the purpose of guiding behaviour. Research in primates has indicated that WM relies on a large network including the prefrontal cortex, various posterior cortical areas, and subcortical nuclei. However, the circuit mapping of WM in rodents is incomplete as it pertains to the specific involvement of thalamocortical and frontoparietal circuitry across WM tasks. In this dissertation, I present the findings of three sets of experiments using two different rodent WM tasks: The odour span task (OST), an incrementing delayed non-matching-to-sample task using odours, and; the Trial-Unique Non-matching-to-Location (TUNL) task, a touchscreen-based visuospatial delayed non-matching-to-sample task. 1) I found evidence that the OST relies on a thalamocortical circuit connecting the medial prefrontal cortex (mPFC) and the mediodorsal thalamus (mdThal). Moreover, the mPFC and mdThal played dissociable roles in the foraging element of the OST, with mdThal inactivation causing a dramatic reduction in exploratory motor activity. 2) I examined the role of the PPC in the OST and found that it is not necessary for OST performance. 3) I found that the PPC is critical for TUNL, confirming that the rodent PPC plays an essential role in visuospatial WM. Additionally, I found that TUNL is independent of NMDA signalling in the PPC and instead depends only on AMPA/Kainate receptors in contrast to previous research showing an important role for NMDA receptors in WM. Overall, the results indicate that thalamocortical and frontoparietal pathways are differentially involved across WM tasks, with frontoparietal circuitry being more sensory modality-specific than thalamocortical circuitry