Inference by Minimizing Size, Divergence, or their Sum

We speed up marginal inference by ignoring factors that do not significantly contribute to overall accuracy. In order to pick a suitable subset of factors to ignore, we propose three schemes: minimizing the number of model factors under a bound on the KL divergence between pruned and full models; minimizing the KL divergence under a bound on factor count; and minimizing the weighted sum of KL divergence and factor count. All three problems are solved using an approximation of the KL divergence than can be calculated in terms of marginals computed on a simple seed graph. Applied to synthetic image denoising and to three different types of NLP parsing models, this technique performs marginal inference up to 11 times faster than loopy BP, with graph sizes reduced up to 98%-at comparable error in marginals and parsing accuracy. We also show that minimizing the weighted sum of divergence and size is substantially faster than minimizing either of the other objectives based on the approximation to divergence presented here.Comment: Appears in Proceedings of the Twenty-Sixth Conference on Uncertainty in Artificial Intelligence (UAI2010

Nicotine treatment decreases food intake and body weight via a leptin-independent pathway in Psammomys obesus

It has been reported previously that leptin may be involved in nicotine\u27s ability to reduce body weight. Our aim was to investigate whether the anorexic action of nicotine is related to the actions of leptin by utilizing lean leptin-sensitive and obese leptin-resistant Psammomys obesus. Lean and obese P. obesus were assigned to receive nicotine sulphate at 6, 9 or 12 mg/day or saline (control) for 9 days (n = 6-10 in each group), administered using mini-osmotic pumps. Food intake, body weight, plasma leptin concentrations, plasma insulin and blood glucose were measured at baseline and throughout the study period. Nicotine treatment reduced food intake by up to 40% in lean and obese P. obesus. Plasma leptin levels fell significantly only in lean nicotine-treated animals, whereas no changes were observed in obese nicotine-treated animals. However, both lean and obese nicotine-treated animals had similar reductions in body weight. Our results show that nicotine has dramatic effects on food intake and body weight, however, these changes appear to be independent of the leptin signalling pathway.<br /

Rapid software prototyping

Rapid Prototyping is an approach to software development which emphasizes quick implementation of a working program. This dissertation makes two principal contributions. First, it provides concepts, techniques, and a philosophy of Rapid Software Prototyping and characterizes the benefits and limitations of its use. Second, it makes a contribution to programming environments which support Rapid Prototyping. An experimental language, Castor, is described which was implemented to validate this approach in the prototyping of Ada programs*. The following summarize the main results of this research:..

Real-Time Health Monitoring System for Mast-Arm Sign Support Structures

There has been an ongoing study conducted by Marquette University and supported by the Wisconsin Highway Research Program that is seeking to understand the risk of fatigue-induced fracture in the connections of mast-arm sign support structures. This study has been brought on by recent problems encountered with the connections contained in, and the in-service performance of, several cantilevered mast-arm sign support structures. A resulting recommendation of phase one in this effort was to monitoring an in-service cantilevered mast-arm sign support structure. The health monitoring system developed in this thesis effort includes a grouping of strain gages (full-bridge arrangements) positioned around the perimeter of the mast-arm tube to monitor wind-induced strain near the mast-arm connection weld toes. This data is automatically recorded (continuously) using the data acquisition system designed and the software developed. Wind speed and direction is simultaneously read through an anemometer, synched to the strain data being acquired, and stored within the DAQ system using the software developed in this thesis. Finally, the thesis includes development of algorithms for synthesizing the data for later use in the WHRP project. The health-monitoring system designed and developed in this thesis will be left in place for future use in the WHRP research effort

Threads, Tweets and TikToks: the ethics and challenges of online qualitative research.

Since the late 90s, social media has revolutionised how people interact and communicate. Among other things, they help old friends keep in touch, people from marginalised communities meet safely, and individuals explore aspects of their identity and sexuality they may not feel comfortable doing in the physical world. However, their often polarised nature also facilitates the spread of often volatile ideas, figures and the communities that form around them. For example, following exposure on TikTok, the provocateur and alleged sex trafficker Andrew Tate was the most Googled man in the world during 2022. This digital infamy allowed his misogynistic content to be shared with young men everywhere, despite having few appearances on traditional media. Hence, online discourses provide a tool for social scientists who want to understand how anti-social ideologies and discourses spread. In this session, psychology lecturer Dr David Smith and MRes student Andrew Meechan will explore the ethics of using social media sites, including X/Twitter, Reddit and TikTok, to understand collective identity and movements. Drawing upon their experiences with researching online misogyny, among other topics, they will explore issues of legitimacy, recruitment, consent, privacy and safeguarding

Polling and the New Hampshire Primary: What to Watch, and Watch Out For

In this brief, authors David Moore and Andrew Smith discuss caveats that should be considered when interpreting what the polls mean for the February 2020 New Hampshire primary

A Connectionist account of Spanish determiner production

Copyright SpringerA Connectionist Network that models the production of simple phonologically coded Spanish Noun Phrases is described. The training data uses type/token frequencies taken directly from a Spanish child's linguistic environment. The training set increases in size in a manner which mirrors the increasing complexity of the real linguistic environment. The results show that the model can learn the task and generalise to unseen Noun Phrase combinations. Moreover the generalisation performance is of a similar nature to that of Spanish children

Modelling the Fluid Mechanics of Cilia and Flagella in Reproduction and Development

Cilia and flagella are actively bending slender organelles, performing functions such as motility, feeding and embryonic symmetry breaking. We review the mechanics of viscous-dominated microscale flow, including time-reversal symmetry, drag anisotropy of slender bodies, and wall effects. We focus on the fundamental force singularity, higher order multipoles, and the method of images, providing physical insight and forming a basis for computational approaches. Two biological problems are then considered in more detail: (1) left-right symmetry breaking flow in the node, a microscopic structure in developing vertebrate embryos, and (2) motility of microswimmers through non-Newtonian fluids. Our model of the embryonic node reveals how particle transport associated with morphogenesis is modulated by the gradual emergence of cilium posterior tilt. Our model of swimming makes use of force distributions within a body-conforming finite element framework, allowing the solution of nonlinear inertialess Carreau flow. We find that a three-sphere model swimmer and a model sperm are similarly affected by shear-thinning; in both cases swimming due to a prescribed beat is enhanced by shear-thinning, with optimal Deborah number around 0.8. The sperm exhibits an almost perfect linear relationship between velocity and the logarithm of the ratio of zero to infinite shear viscosity, with shear-thickening hindering cell progress.Comment: 20 pages, 24 figure

The First Primary: Why New Hampshire?

In this brief, authors David Moore and Andrew Smith describe the origin of the New Hampshire presidential primary and the Iowa presidential caucuses. The developments by which these two small states came to hold the first nominating contests every four years were accidental, generated by a variety of events not at all intended to educate future leaders and certainly not adopted with any expectation that these states would emerge with the enormous influence that comes with being first. But once Iowa and New Hampshire were first, and once they realized the extensive benefits the position brought to them, their leaders fought tenaciously to hold on to their advantage