Engineering a Conformant Probabilistic Planner

We present a partial-order, conformant, probabilistic planner, Probapop which competed in the blind track of the Probabilistic Planning Competition in IPC-4. We explain how we adapt distance based heuristics for use with probabilistic domains. Probapop also incorporates heuristics based on probability of success. We explain the successes and difficulties encountered during the design and implementation of Probapop

A survey of the reasons for the likes and dislikes of first grade children in the Row, Peterson Basal Reader, Round About.

Thesis (Ed.M.)--Boston Universit

Selfish Mutations: the Genetic Basis of the Paternal Age Effect

As the mean age of childrearing grows, the effect of parental age on genetic disease and child health becomes ever more important. A number of autosomal dominant disorders show a dramatic paternal age effect due to selfish mutations: substitutions that grant spermatogonial stem cells (SSCs) a selective advantage in the testes of the father but have a deleterious effect in offspring. I present a mathematical model to analyse the normal function of the stem cell compartment, which provides a framework for SSC renewal and accommodates differences between animal systems. In order to model the SSC mutation accumulation, a Markov chain was used to model the probabilities of mutation and positive selection with cell divisions. This model provided average numbers of mutant sperm produced with increasing paternal age. The proportions of mutant to wildtype cells with increasing paternal age was used to generate a simulated population and observed/expected curves. These were then fitted against existing disease and sequencing data. The parameter for the probability of positive selection per division of a mutant cell was estimated. Incidence of the diseases was predicted closely for most disorders and was influenced by the site-specific mutation rate caused by hypermutable CpG sites and the number of mutable alleles. The incidence of disease was explained satisfactorily only when a combination of positive selection and the site-specific mutation rate were included in the analysis. To provide experimental evidence for the hyposthesis that paternal age effect mutations present a selective advantage, I selected the mutation in the RET (REarranged during Transfection) gene that causes multiple endocrine neoplasia type 2B. SSCs were created by inducing differentiation to spermatogonia of induced pluripotent stem cells. Wildtype and mutant SSCs were generated by transfection with a plasmid containing the normal RET gene and the gene containing the disease mutation, respectively. Mutant SSCs showed increased proliferation in culture. This effect was counteracted when the mutant receptors were saturated with their ligand, GDNF (glial-derived neurotropic factor). This research demonstrated theoretical and experimental evidence for positive selection in SSCs for multiple endocrine neoplasia type 2B and other paternal age effect syndromes

High-stakes lies: Verbal and nonverbal cues to deception in public appeals for help with missing or murdered relatives

This is an Accepted Manuscript of an article published by Taylor & Francis in Psychiatry, Psychology and Law on 23/9/2013 available online: http://wwww.tandfonline.com/10.1080/13218719.2013.839931Low ecological validity is a common limitation in deception studies. The present study investigated the real life, high stake context of public appeals for help with missing or murdered relatives. Behaviours which discriminated between honest and deceptive appeals included some previously identified in research on high stakes lies (deceptive appeals contained more equivocal language, gaze aversion, head shaking, and speech errors), and a number of previously unidentified behaviours (honest appeals contained more references to norms of emotion/behaviour, more expressions of hope of finding the missing relative alive, more expressions of positive emotion towards the relative, more expressions of concern/pain, and an avoidance of brutal language). Case by case analyses yielded 78% correct classifications. Implications are discussed with reference to the importance of using ecologically valid data in deception studies, the context specific nature of some deceptive behaviours, and social interactionist, and individual behavioural profile, accounts of cues to deception.ESRC grant number [ES/I90316X/1

Fully automated segmentation and tracking of the intima media thickness in ultrasound video sequences of the common carotid artery

Abstract—The robust identification and measurement of the intima media thickness (IMT) has a high clinical relevance because it represents one of the most precise predictors used in the assessment of potential future cardiovascular events. To facilitate the analysis of arterial wall thickening in serial clinical investigations, in this paper we have developed a novel fully automatic algorithm for the segmentation, measurement, and tracking of the intima media complex (IMC) in B-mode ultrasound video sequences. The proposed algorithm entails a two-stage image analysis process that initially addresses the segmentation of the IMC in the first frame of the ultrasound video sequence using a model-based approach; in the second step, a novel customized tracking procedure is applied to robustly detect the IMC in the subsequent frames. For the video tracking procedure, we introduce a spatially coherent algorithm called adaptive normalized correlation that prevents the tracking process from converging to wrong arterial interfaces. This represents the main contribution of this paper and was developed to deal with inconsistencies in the appearance of the IMC over the cardiac cycle. The quantitative evaluation has been carried out on 40 ultrasound video sequences of the common carotid artery (CCA) by comparing the results returned by the developed algorithm with respect to ground truth data that has been manually annotated by clinical experts. The measured IMTmean ± standard deviation recorded by the proposed algorithm is 0.60 mm ± 0.10, with a mean coefficient of variation (CV) of 2.05%, whereas the corresponding result obtained for the manually annotated ground truth data is 0.60 mm ± 0.11 with a mean CV equal to 5.60%. The numerical results reported in this paper indicate that the proposed algorithm is able to correctly segment and track the IMC in ultrasound CCA video sequences, and we were encouraged by the stability of our technique when applied to data captured under different imaging conditions. Future clinical studies will focus on the evaluation of patients that are affected by advanced cardiovascular conditions such as focal thickening and arterial plaques

Develop and test fuel cell powered on-site integrated total energy systems: Phase 3, full-scale power plant development

A 25 cell stack of the 13 inch x 23 inch cell size (about 4kW) remains on test after 6000 hours, using simulated reformate fuel. A similar stack was previously shut down after 7000 hours on load. These tests were carried out for the purpose of assessing the durability of fuel cell stack components developed through the end of 1983. In light of the favorable results obtained, a 25kW stack that will contain 175 cells of the same size is being constructed using the same technology base. The components for the 25kW stack have been completed. A methanol steam reformer with a design output equivalent to 50kW has been constructed to serve as a hydrogen generator for the 25kW stack. This reformer and the balance of the fuel processing sub system are currently being tested and debugged. The stack technology development program focused on cost reduction in bipolar plates, nonmetallic cooling plates, and current collecting plates; more stable cathode catalyst support materials; more corrosion resistant metal hardware; and shutdown/start up tolerance

Develop and test fuel cell powered on-site integrated total energy systems

On-going testing of an 11 cell, 10.7 in. x 14 in. stack (about 1 kW) reached 2600 hours on steady load. Nonmetallic cooling plates and an automated electrolyte replenishment system continued to perform well. A 10 cell, 10.7 in. x 14 in. stack was constructed with a modified electrolyte matrix configuration for the purpose of reducing cell IR loss. The desired effect was achieved, but the general cell performance level was irregular. Evaluation is continuing. Preparations for a long term 25 cell, 13 in. x 23 in. test stack (about 4 kW) approached completion. Start up in early May 1984 is expected

Mn-Catalyzed Oxidation of Naphthalenediol

This study investigates the effects that manganese(IV) dioxide particles have on 2,3-naphthalenediol at varying pH levels (i.e., initial pH of 4.58, 5.85, and 8.75) and under different organic concentration conditions (4×10−3, 4×10−4, and 4×10−5 M), and assesses the importance of Mn oxides on abiotic catalysis of the multiple-ringed aromatic compound. Proton concentration affected the rates of reductive dissolution; as the pH values increased, the rate of reductive dissolution decreased, as predicted by theory. Also, as the concentration of naphthalenediol increased, the rate of reductive dissolution increased, although not proportionally; thus indicating that a majority of the active sites had been occupied. In addition, the results tend to confirm that electron transfer/organic release from the oxide surface is the rate-limiting step. This study demonstrates that in an oxic environment and in the presence of 2,3-naphthalenediol, MnO2 particles undergo reductive dissolution; in the process, naphthalenediol is oxidized. An oxidation by-product of reductive dissolution is an insoluble polymerized organic. The organic by-product was deep-brown in appearance, very similar to that of humified material. Using infrared spectroscopy, energy-dispersive x-ray analysis, and a microelemental analysis, the humified products appeared to be comprised mainly of constituents originating from naphthalenediol