Arctic Ecology: A Decade of Experience

A quick glance at the title of this presentation and the reader braces himself for another antipollution or “save-the-sod” type of discourse that has become so popular these days. I do not wish to detract from the importance or the need for such efforts but I would like to address myself to the the broader meaning of the term. Ecology--the word comes from the Greek root “oikos” which means house or household. What I’d like to do is to tell you about this “house” I’ve been living in for the past 10 years

Quantification of Thoracic Aorta Blood Flow by Magnetic Resonance Imaging During Supine Cycling Exercise of Increasing Intensity

Poster presentation from the 16th Annual SCMR Scientific Sessions San Francisco, CA, USA. 31 January - 3 February 2013

A Merger Scenario for the Dynamics of Abell 665

We present new redshift measurements for 55 galaxies in the vicinity of the rich galaxy cluster Abell 665. When combined with results from the literature, we have good velocity measurements for a sample of 77 confirmed cluster members from which we derive the cluster's redshift z=0.1829 +/- 0.0005 and line-of-sight velocity dispersion of 1390 +/- 120 km/s. Our analysis of the kinematical and spatial data for the subset of galaxies located within the central 750 kpc reveals only subtle evidence for substructure and non-Gaussianity in the velocity distribution. We find that the brightest cluster member is not moving significantly relative to the other galaxies near the center of the cluster. On the other hand, our deep ROSAT high resolution image of A665 shows strong evidence for isophotal twisting and centroid variation, thereby confirming previous suggestions of significant substructure in the hot X-ray--emitting intracluster gas. In light of this evident substructure, we have compared the optical velocity data with N-body simulations of head-on cluster mergers. We find that a merger of two similar mass subclusters (mass ratios of 1:1 or 1:2) seen close to the time of core-crossing produces velocity distributions that are consistent with that observed.Comment: 30 pages and 7 figures. Accepted by the Astrophysical Journal Full resoultion figures 1 and 3 available in postscript at http://www.physics.rutgers.edu/~percy/A665paper.htm

Bismuth coordination networks containing deferiprone: synthesis, characterisation, stability and antibacterial activity

A series of bismuth–dicarboxylate–deferiprone coordination networks have been prepared and structurally characterised. The new compounds have been demonstrated to release the iron overload drug deferiprone on treatment with PBS and have also been shown to have antibacterial activity against H. pylori

Determining the Cosmic Distance Scale from Interferometric Measurements of the Sunyaev-Zel'dovich Effect

We determine the distances to 18 galaxy clusters with redshifts ranging from z~0.14 to z~0.78 from a maximum likelihood joint analysis of 30 GHz interferometric Sunyaev-Zel'dovich effect (SZE) and X-ray observations. We model the intracluster medium (ICM) using a spherical isothermal beta model. We quantify the statistical and systematic uncertainties inherent to these direct distance measurements, and we determine constraints on the Hubble parameter for three different cosmologies. These distances imply a Hubble constant of 60 (+4, -4) (+13, -18) km s-1 Mpc-1 for an Omega_M = 0.3, Omega_Lambda = 0.7 cosmology, where the uncertainties correspond to statistical followed by systematic at 68% confidence. With a sample of 18 clusters, systematic uncertainties clearly dominate. The systematics are observationally approachable and will be addressed in the coming years through the current generation of X-ray satellites (Chandra & XMM-Newton) and radio observatories (OVRO, BIMA, & VLA). Analysis of high redshift clusters detected in future SZE and X-ray surveys will allow a determination of the geometry of the universe from SZE determined distances.Comment: ApJ Submitted; 40 pages, 9 figures (fig 3 B&W for size constraint), 13 tables, uses emulateapj5 styl

Best practices for constructing, preparing, and evaluating protein-ligand binding affinity benchmarks

Free energy calculations are rapidly becoming indispensable in structure-enabled drug discovery programs. As new methods, force fields, and implementations are developed, assessing their expected accuracy on real-world systems (benchmarking) becomes critical to provide users with an assessment of the accuracy expected when these methods are applied within their domain of applicability, and developers with a way to assess the expected impact of new methodologies. These assessments require construction of a benchmark - a set of well-prepared, high quality systems with corresponding experimental measurements designed to ensure the resulting calculations provide a realistic assessment of expected performance when these methods are deployed within their domains of applicability. To date, the community has not yet adopted a common standardized benchmark, and existing benchmark reports suffer from a myriad of issues, including poor data quality, limited statistical power, and statistically deficient analyses, all of which can conspire to produce benchmarks that are poorly predictive of real-world performance. Here, we address these issues by presenting guidelines for (1) curating experimental data to develop meaningful benchmark sets, (2) preparing benchmark inputs according to best practices to facilitate widespread adoption, and (3) analysis of the resulting predictions to enable statistically meaningful comparisons among methods and force fields

Client and therapist views of contextual factors related to termination from psychotherapy: A comparison between unilateral and mutual terminators

Contextual variables potentially influencing premature termination were examined. Clients (n = 83) and therapists (n = 35) provided parallel data on early working alliance, psychotherapy termination decision (unilateral vs. mutual), clients’ reasons for termination, and barriers to treatment participation. When clients unilaterally ended therapy, therapists were only partially aware of either the extent of clients’ perceived improvements or their dissatisfaction. When termination was mutually determined, there were no differences between client and therapist ratings of termination reasons. Although working alliance and barriers to treatment participation were rated as lower in the context of unilateral termination by clients and therapists, all clients rated the early alliance and barriers to treatment more highly than did therapists. Results have implications for understanding premature termination and suggest future research examining the utility of therapist feedback regarding contextual variables in terms of retaining clients in therapy