Broadband Records of Earthquakes in Deep Gold Mines and a Comparison with Results from SAFOD, California

For one week during September 2007, we deployed a temporary network of field recorders and accelerometers at four sites within two deep, seismically active mines. The ground-motion data, recorded at 200 samples/sec, are well suited to determining source and ground-motion parameters for the mining-induced earthquakes within and adjacent to our network. Four earthquakes with magnitudes close to 2 were recorded with high signal/noise at all four sites. Analysis of seismic moments and peak velocities, in conjunction with the results of laboratory stick-slip friction experiments, were used to estimate source processes that are key to understanding source physics and to assessing underground seismic hazard. The maximum displacements on the rupture surfaces can be estimated from the parameter Rv, where v is the peak ground velocity at a given recording site, and R is the hypocentral distance. For each earthquake, the maximum slip and seismic moment can be combined with results from laboratory friction experiments to estimate the maximum slip rate within the rupture zone. Analysis of the four M 2 earthquakes recorded during our deployment and one of special interest recorded by the in-mine seismic network in 2004 revealed maximum slips ranging from 4 to 27 mm and maximum slip rates from 1.1 to 6:3 m=sec. Applying the same analyses to an M 2.1 earthquake within a cluster of repeating earthquakes near the San Andreas Fault Observatory at Depth site, California, yielded similar results for maximum slip and slip rate, 14 mm and 4:0 m=sec

Stellar Variability in the Globular Cluster Terzan 5

We present the results of a search for variability in and near the core of the metal-rich, obscured globular cluster Terzan 5, using NICMOS on HST. This extreme cluster has approximately solar metallicity and a central density that places it in the upper few percent of all clusters. It is estimated to have the highest interaction rate of any galactic globular cluster. The large extinction towards Terzan 5 and the severe stellar crowding near the cluster center present a substantial observational challenge. Using time series analysis we discovered two variable stars in this cluster. The first is a RRab Lyrae variable with a period of ~0.61 days, a longer period than that of field stars with similar high metallicities. This period is, however, shorter than the average periods of RR Lyraes found in the metal-rich globular clusters NGC 6441, NGC 6388 and 47 Tuc. The second variable is a blue star with a 7-hour period sinusoidal variation and a likely orbital period of 14 hours. This star is probably an eclipsing blue straggler, or (less likely) the infrared counterpart to the low mass X-ray binary known in Terzan 5. Due to the extreme crowding and overlapping Airy profile of the IR PSF, we fall short of our original goal of detecting CVs via Palpha emission and detecting variable infrared emission from the location of the binary MSP in Terzan 5.Comment: 17 pages including 12 figures. Accepted for publication in Ap

Embryonic Pattern Scaling Achieved by Oppositely Directed Morphogen Gradients

Morphogens are proteins, often produced in a localised region, whose concentrations spatially demarcate regions of differing gene expression in developing embryos. The boundaries of expression must be set accurately and in proportion to the size of the one-dimensional developing field; this cannot be accomplished by a single gradient. Here, we show how a pair of morphogens produced at opposite ends of a developing field can solve the pattern-scaling problem. In the most promising scenario, the morphogens effectively interact according to the annihilation reaction $A+B\to\emptyset$ and the switch occurs according to the absolute concentration of $A$ or $B$. In this case embryonic markers across the entire developing field scale approximately with system size; this cannot be achieved with a pair of non-interacting gradients that combinatorially regulate downstream genes. This scaling occurs in a window of developing-field sizes centred at a few times the morphogen decay length.Comment: 24 pages; 11 figures; uses iopar

HST-NICMOS Observations of Terzan 5: Stellar Content and Structure of the Core

We report results from HST-NICMOS imaging of the extremely dense core of the globular cluster Terzan 5. This highly obscured bulge cluster has been estimated to have one of the highest collision rates of any galactic globular cluster, making its core a particularly conducive environment for the production of interacting binary systems. We have reconstructed high-resolution images of the central 19"x19" region of Terzan 5 by application of the drizzle algorithm to dithered NIC2 images in the F110W, F187W, and F187N near-infrared filters. We have used a DAOPHOT/ALLSTAR analysis of these images to produce the deepest color-magnitude diagram (CMD) yet obtained for the core of Terzan 5. We have also analyzed the parallel 11"X11" NIC1 field, centered 30" from the cluster center and imaged in F110W and F160W, and an additional NIC2 field that is immediately adjacent to the central field. This imaging results in a clean detection of the red-giant branch and horizontal branch in the central NIC2 field, and the detection of these plus the main-sequence turnoff and the upper main sequence in the NIC1 field. We have constructed an H versus J-H CMD for the NIC1 field. We obtain a new distance estimate of 8.7 kpc, which places Terzan 5 within less than 1 kpc of the galactic center. We have also determined a central surface-density profile which results in a maximum likelihood estimate of 7.9" +/- 0.6" for the cluster core radius. We discuss the implications of these results for the dynamical state of Terzan 5.Comment: 17 pages, 9 figures, accepted for publication in ApJ, for May 20, 200

Preferences related to attention-deficit/hyperactivity disorder and its treatment

Kate Van Brunt1, Louis S Matza1, Peter M Classi2, Joseph A Johnston21Center for Health Outcomes Research at United BioSource Corporation, Bethesda, MD, USA; 2Eli Lilly and Company, Indianapolis, IN, USAObjectives: A growing body of literature has highlighted the importance of considering patient preferences as part of the medical decision-making process. The purpose of the current review was to identify and summarize published research on preferences related to attention-deficit/hyperactivity disorder (ADHD) and its treatment, while suggesting directions for future research.Methods: A literature search identified 15 articles that included a choice-based assessment of preferences related to ADHD.Results: The 15 studies were grouped into four categories based on preference content: preference for a treatment directly experienced by the respondent or the respondent's child; preference for general treatment approaches; preference for a specific treatment attribute or outcome; and preference for aspects of ADHD-related treatment. Preference assessment methods ranged from global single items to detailed choice-based procedures, with few studies using rigorously developed assessment methods. Respondents included patients with ADHD, clinicians, parents, teachers, and survey respondents from the general population. Factors influencing preference include treatment characteristics, effectiveness for specific symptoms, side effects, and respondent demographics. Minimal research has examined treatment preferences of adults with ADHD.Discussion: Because there is no dominant treatment known to be the first choice for all patients, ADHD is a condition for which individual preferences can play an important role when making treatment decisions for individual patients. Given the potential role of preferences in clinical decision-making, more research is needed to better understand the preferences of patients with ADHD and other individuals who are directly affected by the disorder, such as parents and teachers.Keywords: patient preference, ADHD, parent preference, utilit

"No Going Back?" The final report of the Effective Records Management Project

The overall objective of the Effective Records Management project was the provision of ‘protocols and tools for the effective management of information in the digital order, with particular attention to information held in a document-based form’ . The project developed a demonstrator system which addressed the full range of issues involved in the management of a ‘testbed’ of digital records in the form of documents, from their creation through distribution and use to their final disposal or permanent retention. The testbed selected was the records of a subset of the university’s committees and was used to develop ideas and to assess how well they worked in practice. This project report indicates that the ERM project provides an investment in the future, opportunities for better information use or re-use, identification of legal risks and identification of good practice whether you be an administrator, a computing scientist, an archivist, a librarian or an information services manager

"No Going Back?" The final report of the Effective Records Management Project

The overall objective of the Effective Records Management project was the provision of ‘protocols and tools for the effective management of information in the digital order, with particular attention to information held in a document-based form’ . The project developed a demonstrator system which addressed the full range of issues involved in the management of a ‘testbed’ of digital records in the form of documents, from their creation through distribution and use to their final disposal or permanent retention. The testbed selected was the records of a subset of the university’s committees and was used to develop ideas and to assess how well they worked in practice. This project report indicates that the ERM project provides an investment in the future, opportunities for better information use or re-use, identification of legal risks and identification of good practice whether you be an administrator, a computing scientist, an archivist, a librarian or an information services manager

Effects of stratospheric aerosol surface processes on the LLNL two-dimensional zonally averaged model

We have investigated the effects of incorporating representations of heterogeneous chemical processes associated with stratospheric sulfuric acid aerosol into the LLNL two-dimensional, zonally averaged, model of the troposphere and stratosphere. Using distributions of aerosol surface area and volume density derived from SAGE II satellite observations, we were primarily interested in changes in partitioning within the Cl- and N- families in the lower stratosphere, compared to a model including only gas phase photochemical reactions. We have considered the heterogeneous hydrolysis reactions N2O5 + H2O(aerosol) yields 2 HNO3 and ClONO2 + H2O(aerosol) yields HOCl + HNO3 alone and in combination with the proposed formation of nitrosyl sulfuric acid (NSA) in the aerosol and its reaction with HCl. Inclusion of these processes produces significant changes in partitioning in the NO(y) and ClO(y) families in the middle stratosphere

Picosecond electric-field-induced threshold switching in phase-change materials

Many chalcogenide glasses undergo a breakdown in electronic resistance above a critical field strength. Known as threshold switching, this mechanism enables field-induced crystallization in emerging phase-change memory. Purely electronic as well as crystal nucleation assisted models have been employed to explain the electronic breakdown. Here, picosecond electric pulses are used to excite amorphous Ag$_4$In$_3$Sb$_{67}$Te$_{26}$. Field-dependent reversible changes in conductivity and pulse-driven crystallization are observed. The present results show that threshold switching can take place within the electric pulse on sub-picosecond time-scales - faster than crystals can nucleate. This supports purely electronic models of threshold switching and reveals potential applications as an ultrafast electronic switch.Comment: 6 pages manuscript with 3 figures and 8 pages supplementary materia