PORGY: a Visual Analytics Platform for System Modelling and Analysis Based on Graph Rewriting

PORGY is a visual environment for rule-based modelling based on port graphs and port graph rewrite rules whose application is steered by rewriting strategies. The focus of this demonstration is the visual and interactive features offered by PORGY, which facilitate an exploratory approach to model, simu- late and analyse different ways of applying the rules while recording the model evolution, as well as tracking and plotting system parameters

Development of catalysts for the addition of N-H and O-H to carbon-carbon double bonds

The addition of O-H and N-H bonds across carbon-carbon double bonds offers a direct way of synthesising a variety of organic molecules. These reactions have attracted considerable interest in academic research and the chemical/pharmaceutical industry in recent years due to its atom economy. Nevertheless, there remains a considerably challenge to control the regioselectivity and the stereoselectivity of this reaction. This PhD thesis describes the investigation into the discovery and development of a general method for catalytic hydroamination (HA), hydroalkoxylation and hydrooxyacylation of olefins. Air- and moisture-stable transition metal catalysts were the main focus of this study. The introductory Chapter provides an overview of recent advances in N-H addition reactions involving late transition metal catalysts. In Chapter 2, rhodium and ruthenium complexes were examined as catalysts for the addition of N-H bonds to alkenes. The combination of (RuCl2)n/dppb/AgOTf generated a catalyst effective for the addition of methyl carbamate to norbornene in a modest yield. Copper (II) trifluoromethanesulfonate was discovered to be an efficient catalyst for the addition of carboxylic acids, phenols and alcohols to norbornene. A selection of norbornyl esters and ethers were formed in good to excellent yields. In the following Chapter, the combination of copper (II) trifluoromethanesulfonate and diphosphine ligands was successfully applied to the addition of sulfonamides and carbamates to vinylarenes, 1,3-dienes and norbornene in good to excellent yields. In Chapter 4, the intramolecular hydroamination reaction was developed. The synthesis of several acyclic precursors were described, along with attempts to cyclise them. The chapter ends with the attempted synthesis of tricyclic molecules using a palladium-catalysed methodology. The last Chapter contains experimental procedures and characterisation data of all the compounds synthesised during the course of this project

Semantic Social Networks: A Mixed Methods Approach to Digital Ethnography

International audienc

Stellar Population Models and Individual Element Abundances I: Sensitivity of Stellar Evolution Models

Integrated light from distant galaxies is often compared to stellar population models via the equivalent widths of spectral features--spectral indices--whose strengths rely on the abundances of one or more elements. Such comparisons hinge not only on the overall metal abundance but also on relative abundances. Studies have examined the influence of individual elements on synthetic spectra but little has been done to address similar issues in the stellar evolution models that underlie most stellar population models. Stellar evolution models will primarily be influenced by changes in opacities. In order to explore this issue in detail, twelve sets of stellar evolution tracks and isochrones have been created at constant heavy element mass fraction Z that self-consistently account for varying heavy element mixtures. These sets include scaled-solar, alpha-enhanced, and individual cases where the elements C, N, O, Ne, Mg, Si, S, Ca, Ti, and Fe have been enhanced above their scaled-solar values. The variations that arise between scaled-solar and the other cases are examined with respect to the H-R diagram and main sequence lifetimes.Comment: 33 pages, 13 figures, accepted to Ap

Incoherent white-light solitons in nonlinear periodic lattices

We predict the existence of lattice solitons made of incoherent white light: lattice solitons made of light originating from an ordinary incandescent light bulb. We find that the intensity structure and spatial power spectra associated with different temporal frequency constituents of incoherent white-light lattice solitons (IWLLSs) arrange themselves in a characteristic fashion, with the intensity structure more localized at higher frequencies, and the spatial power spectrum more localized at lower frequencies; the spatial correlation distance is larger at lower frequency constituents of IWLLSs. This characteristic shape of incoherent white-light lattice solitons reflects the fact that diffraction is stronger for lower temporal frequency constituents, while higher frequencies experience stronger effective nonlinearity and deeper lattice structure

Learning parameters for the sequence constraint from solutions

This paper studies the problem of learning parameters for global constraints such as Sequence from a small set of positive examples. The proposed technique computes the probability of observing a given constraint in a random solution. This probability is used to select the more likely constraint in a list of candidates. The learning method can be applied to both soft and hard constraint

The Bolocam Galactic Plane Survey IX: Data Release 2 and Outer Galaxy Extension

We present a re-reduction and expansion of the Bolocam Galactic Plane Survey, first presented by Aguirre et al. (2011) and Rosolowsky et al. (2010). The BGPS is a 1.1 mm survey of dust emission in the Northern galactic plane, covering longitudes -10 < \ell < 90 and latitudes |b| < 0.5 with a typical 1-\sigma RMS sensitivity of 30-100 mJy in a 33" beam. Version 2 of the survey includes an additional 20 square degrees of coverage in the 3rd and 4th quadrants and 2 square degrees in the 1st quadrant. The new data release has improved angular recovery, with complete recovery out to 80" and partial recovery to 300", and reduced negative bowls around bright sources resulting from the atmospheric subtraction process. We resolve the factor of 1.5 flux calibration offset between the v1.0 data release and other data sets and determine that there is no offset between v2.0 and other data sets. The v2.0 pointing accuracy is tested against other surveys and demonstrated to be accurate and an improvement over v1.0. We present simulations and tests of the pipeline and its properties, including measurements of the pipeline's angular transfer function. The Bolocat cataloging tool was used to extract a new catalog, which includes 8594 sources, with 591 in the expanded regions. We have demonstrated that the Bolocat 40" and 80" apertures are accurate even in the presence of strong extended background emission. The number of sources is lower than in v1.0, but the amount of flux and area included in identified sources is larger.Comment: 36 pages, 16 figures, accepted to ApJS. Data available from http://irsa.ipac.caltech.edu/data/BOLOCAM_GPS

Discovery of a Role for Rab3b in Habituation and Cocaine Induced Locomotor Activation in Mice Using Heterogeneous Functional Genomic Analysis

Substance use disorders are prevalent and present a tremendous societal cost but the mechanisms underlying addiction behavior are poorly understood and few biological treatments exist. One strategy to identify novel molecular mechanisms of addiction is through functional genomic experimentation. However, results from individual experiments are often noisy. To address this problem, the convergent analysis of multiple genomic experiments can discern signal from these studies. In the present study, we examine genetic loci that modulate the locomotor response to cocaine identified in the recombinant inbred (BXD RI) genetic reference population. We then applied the GeneWeaver software system for heterogeneous functional genomic analysis to integrate and aggregate multiple studies of addiction genomics, resulting in the identification o