Geometric approach to Fletcher's ideal penalty function

Original article can be found at: www.springerlink.com Copyright Springer. [Originally produced as UH Technical Report 280, 1993]In this note, we derive a geometric formulation of an ideal penalty function for equality constrained problems. This differentiable penalty function requires no parameter estimation or adjustment, has numerical conditioning similar to that of the target function from which it is constructed, and also has the desirable property that the strict second-order constrained minima of the target function are precisely those strict second-order unconstrained minima of the penalty function which satisfy the constraints. Such a penalty function can be used to establish termination properties for algorithms which avoid ill-conditioned steps. Numerical values for the penalty function and its derivatives can be calculated efficiently using automatic differentiation techniques.Peer reviewe

Geometry Optimization of Crystals by the Quasi-Independent Curvilinear Coordinate Approximation

The quasi-independent curvilinear coordinate approximation (QUICCA) method [K. N\'emeth and M. Challacombe, J. Chem. Phys. {\bf 121}, 2877, (2004)] is extended to the optimization of crystal structures. We demonstrate that QUICCA is valid under periodic boundary conditions, enabling simultaneous relaxation of the lattice and atomic coordinates, as illustrated by tight optimization of polyethylene, hexagonal boron-nitride, a (10,0) carbon-nanotube, hexagonal ice, quartz and sulfur at the $\Gamma$-point RPBE/STO-3G level of theory.Comment: Submitted to Journal of Chemical Physics on 7/7/0

Older adults and withdrawal from benzodiazepine hypnotics in general practice: effects on cognitive function, sleep, mood and quality of life

Background: Older adults are the main recipients of repeat prescriptions for benzodiazepine (BZD) hypnotics. BZDs can impair cognitive function and may not aid sleep when taken continuously for years. This study therefore aimed to determine if withdrawing from BZDs leads to changes in patients' cognitive function, quality of life, mood and sleep. Method: One hundred and ninety-two long-term users of BZD hypnotics, aged [gt-or-equal, slanted]65 years, were identified in 25 general practices. One hundred and four who wished to withdraw were randomly allocated to one of two groups under double-blind, placebo controlled conditions: group A's BZD dose was tapered from week 1 of the trial; group B were given their usual dose for 12 weeks and then it was tapered. An additional group (C) of 35 patients who did not wish to withdraw from BZDs participated as ‘continuers’. All patients were assessed at 0, 12 and 24 weeks and 50% were re-assessed at 52 weeks. Results: Sixty per cent of patients had taken BZDs continuously for >10 years; 27% for >20 years. Of all patients beginning the trial, 80% had successfully withdrawn 6 months later. There was little difference between groups A and B, but these groups differed from continuers (C) in that the performance of the withdrawers on several cognitive/psychomotor tasks showed relative improvements at 24 or 52 weeks. Withdrawers and continuers did not differ in sleep or BZD withdrawal symptoms. Conclusions: These results have clear implications for clinical practice. Withdrawal from BZDs produces some subtle cognitive advantages for older people, yet little in the way of withdrawal symptoms or emergent sleep difficulties. These findings also suggest that, taken long-term, BZDs do not aid sleep

Same traits, different variance : Item-Level Variation Within Personality Measures

© 2014 the Author(s). This article has been published under the terms of the Creative Commons Attribution License. Without requesting permission from the Author or SAGE, you may further copy, distribute, transmit, and adapt the article, with the condition that the Author and SAGE Open are in each case credited as the source of the article. The version of record, Jamie S. Churcyard, Karen J. Pine, Shivani Sharma, Ben (C) Fletcher, ' Same Traits, Difference Variance: Item-Level Variation Within Personality Measures', SAGE Open, 2014, is available online via doi: 10.1177/2158244014522634Personality trait questionnaires are regularly used in individual differences research to examine personality scores between participants, although trait researchers tend to place little value on intra-individual variation in item ratings within a measured trait. The few studies that examine variability indices have not considered how they are related to a selection of psychological outcomes, so we recruited 160 participants (age M = 24.16, SD = 9.54) who completed the IPIP-HEXACO personality questionnaire and several outcome measures. Heterogenous within-subject differences in item ratings were found for every trait/facet measured, with measurement error that remained stable across the questionnaire. Within-subject standard deviations, calculated as measures of individual variation in specific item ratings within a trait/facet, were related to outcomes including life satisfaction and depression. This suggests these indices represent valid constructs of variability, and that researchers administering behavior statement trait questionnaires with outcome measures should also apply item-level variability indices.Peer reviewedFinal Published versio

The NASA/MSFC global reference atmospheric model: MOD 3 (with spherical harmonic wind model)

Improvements to the global reference atmospheric model are described. The basic model includes monthly mean values of pressure, density, temperature, and geostrophic winds, as well as quasi-biennial and small and large scale random perturbations. A spherical harmonic wind model for the 25 to 90 km height range is included. Below 25 km and above 90 km, the GRAM program uses the geostrophic wind equations and pressure data to compute the mean wind. In the altitudes where the geostrophic wind relations are used, an interpolation scheme is employed for estimating winds at low latitudes where the geostrophic wind relations being to mesh down. Several sample wind profiles are given, as computed by the spherical harmonic model. User and programmer manuals are presented

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

Theory of phonon-drag thermopower of extrinsic semiconducting single-wall carbon nanotubes and comparison with previous experimental data

A theoretical model for the calculation of the phonon-drag thermopower, $S^{g}$, in degenerately doped semiconducting single-wall carbon nanotubes (SWCNTs) is proposed. Detailed calculations of $S^{g}$ are performed as a function of temperature, tube radius and position of the Fermi level. We derive a simple analytical expression for $S^{g}$ that can be utilized to determine the free carrier density in doped nanotubes. At low temperatures $S^{g}$ shows an activated behavior characteristic of the one-dimensional (1D) character of carriers. Screening effects are taken into account and it is found that they dramatically reduce the magnitude of $S^{g}$. Our results are compared with previous published experimental data in bulk p-doped SWCNT materials. Excellent agreement is obtained in the temperature range 10-200 K for a consistent set of parameters. This is a striking result in view of the complexity of these systems.Comment: 21 pages, 6 figures. This version has been accepted for publication in Phys. Rev.

Transverse Magnetoresistance of GaAs/AlGaAs Heterojunctions in the Presence of Parallel Magnetic Fields

We have calculated the resistivity of a GaAs\slash AlGaAs heterojunction in the presence of both an in--plane magnetic field and a weak perpendicular component using a semiclassical Boltzmann transport theory. These calculations take into account fully the distortion of the Fermi contour which is induced by the parallel magnetic field. The scattering of electrons is assumed to be due to remote ionized impurities. A positive magnetoresistance is found as a function of the perpendicular component, in good qualitative agreement with experimental observations. The main source of this effect is the strong variation of the electronic scattering rate around the Fermi contour which is associated with the variation in the mean distance of the electronic states from the remote impurities. The magnitude of the positive magnetoresistance is strongly correlated with the residual acceptor impurity density in the GaAs layer. The carrier lifetime anisotropy also leads to an observable anisotropy in the resistivity with respect to the angle between the current and the direction of the in--plane magnetic field.Comment: uuencoded file containing a 26 page RevTex file and 14 postscript figures. Submitted to Phys. Rev.

Evaluation of the Equality, Diversity and Inclusion Grants in English Further Education

The Equality, Diversity and Inclusion (EDI) Grants, managed by the Skills Funding Agency (the Agency) and the Learning and Skills Improvement Service (LSIS) aimed to support innovative and sustainable projects which developed the capacity of the sector to meet the public sector Equality Duty. This report evaluates three years of the EDI Grants, 2010-2011 (EDI-2), 2011-2012 (EDI-3) and 2012-2013 (EDI-4). The Grants were open to organisations in England whose primary function was to provide further education and training, and well as to National Careers Service prime providers

Discovery of molecular subtypes in leiomyosarcoma through integrative molecular profiling.

Leiomyosarcoma (LMS) is a soft tissue tumor with a significant degree of morphologic and molecular heterogeneity. We used integrative molecular profiling to discover and characterize molecular subtypes of LMS. Gene expression profiling was performed on 51 LMS samples. Unsupervised clustering showed three reproducible LMS clusters. Array comparative genomic hybridization (aCGH) was performed on 20 LMS samples and showed that the molecular subtypes defined by gene expression showed distinct genomic changes. Tumors from the muscle-enriched cluster showed significantly increased copy number changes (P=0.04). A majority of the muscle-enriched cases showed loss at 16q24, which contains Fanconi anemia, complementation group A, known to have an important role in DNA repair, and loss at 1p36, which contains PRDM16, of which loss promotes muscle differentiation. Immunohistochemistry (IHC) was performed on LMS tissue microarrays (n=377) for five markers with high levels of messenger RNA in the muscle-enriched cluster (ACTG2, CASQ2, SLMAP, CFL2 and MYLK) and showed significantly correlated expression of the five proteins (all pairwise P<0.005). Expression of the five markers was associated with improved disease-specific survival in a multivariate Cox regression analysis (P<0.04). In this analysis that combined gene expression profiling, aCGH and IHC, we characterized distinct molecular LMS subtypes, provided insight into their pathogenesis, and identified prognostic biomarkers