WorldWideScience

Sample records for 1000au scale properties

  1. Observations of Infalling and Rotational Motions on a 1,000-AU Scale around 17 Class 0 and 0/I Protostars: Hints of Disk Growth and Magnetic Braking?

    Yen, Hsi-Wei; Takakuwa, Shigehisa; Ho, Paul T P; Ohashi, Nagayoshi; Tang, Ya-Wen

    2014-01-01

    We perform imaging and analyses of SMA 1.3 mm continuum, C18O (2-1) and 12CO (2-1) line data of 17 Class 0 and 0/I protostars to study their gas kinematics on a 1,000-AU scale. Continuum and C18O (2-1) emission are detected toward all the sample sources and show central primary components with sizes of ~600-1,500 AU associated with protostars. The velocity gradients in C18O (2-1) have wide ranges of orientations from parallel to perpendicular to the outflows, with magnitudes from ~1 to ~530 km/s/pc. We construct a simple kinematic model to reproduce the observed velocity gradients, estimate the infalling and rotational velocities, and infer the disk radii and the protostellar masses. The inferred disk radii range from 500 AU with estimated protostellar masses from 1 Msun. Our results hint that both large and small disks are possibly present around Class 0 protostars, which could be a sign of disk growth at the Class 0 stage. In addition, the directions of the overall velocity gradients in 7 out of the 17 sour...

  2. FOCAL mission to 550 thru 1000 AU: Status review 2009

    Maccone, Claudio

    2010-09-01

    This paper presents a 2009 status review of the "FOCAL" space mission studied by this author and others since 1992 and formally proposed to ESA for consideration after the year 2000. The FOCAL probe is intended to reach distances between 550 and 1000 AU to exploit the huge radio magnification provided there by the gravitational lens of the Sun, as predicted by the general theory of relativity. However, the alignment between the radio source (any star, for instance), the center of the Sun and the FOCAL spacecraft is rather strict, and so it will be necessary to send a FOCAL probe in the opposite sky direction for any stellar system we wish to observe. For instance, before humanity ever embarked in a true interstellar mission even to the closest stars, the Alpha Centauri three stars system at 4.40 light-years from us, it plainly appears that before launching a really interstellar spacecraft it will be better to send a FOCAL probe in the opposite direction of the sky. In fact, the distance it must reach is 278 times smaller than 4.40 light-years, or, in other words, assuming equal engineering problems, FOCAL will take 278 times less than the trip to Alpha Centauri. This makes the Sun focus a reasonable target for our probes to reach within this century already. This paper describes the gravitational lens of the Sun and an updated status review of FOCAL including:(1) The new book by the author, published in March 2009 and entitled "Deep Space Flight and Communications".(2) The utilization of the relativistic KLT (Karhunen-Loève Transform) instead of the classical FFT to insure optimal telecommunications with the Earth during such a relativistic flight.

  3. EARLY STAGES OF CLUSTER FORMATION: FRAGMENTATION OF MASSIVE DENSE CORES DOWN TO {approx}< 1000 AU

    Palau, Aina; Girart, Josep M. [Institut de Ciencies de l' Espai (CSIC-IEEC), Campus UAB-Facultat de Ciencies, Torre C5-parell 2, E-08193 Bellaterra, Catalunya (Spain); Fuente, Asuncion [Observatorio Astronomico Nacional, P.O. Box 112, E-28803 Alcala de Henares, Madrid (Spain); Estalella, Robert [Departament d' Astronomia i Meteorologia (IEEC-UB), Institut de Ciencies del Cosmos, Universitat de Barcelona, Marti Franques, 1, E-08028 Barcelona (Spain); Ho, Paul T. P.; Zhang, Qizhou [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Sanchez-Monge, Alvaro; Fontani, Francesco; Cesaroni, Riccardo [Osservatorio Astrofisico di Arcetri, INAF, Lago E. Fermi 5, I-50125 Firenze (Italy); Busquet, Gemma [INAF-Istituto di Astrofisica e Planetologia Spaziali, Area di Recerca di Tor Vergata, Via Fosso Cavaliere 100, I-00133 Roma (Italy); Commercon, Benoit; Hennebelle, Patrick [Laboratoire de Radioastronomie, UMR CNRS 8112, Ecole Normale Superieure et Observatoire de Paris, 24 rue Lhomond, F-75231 Paris Cedex 05 (France); Boissier, Jeremie [Istituto di Radioastronomia, INAF, Via Gobetti 101, I-40129 Bologna (Italy); Zapata, Luis A., E-mail: palau@ieec.uab.es [Centro de Radioastronomia y Astrofisica, Universidad Nacional Autonoma de Mexico, P.O. Box 3-72, 58090 Morelia, Michoacan (Mexico)

    2013-01-10

    In order to study the fragmentation of massive dense cores, which constitute the cluster cradles, we observed the continuum at 1.3 mm and the CO (2-1) emission of four massive cores with the Plateau de Bure Interferometer in the most extended configuration. We detected dust condensations down to {approx}0.3 M {sub Sun} and separate millimeter sources down to 0.''4 or {approx}< 1000 AU, comparable to the sensitivities and separations reached in optical/infrared studies of clusters. The CO (2-1) high angular resolution images reveal high-velocity knots usually aligned with previously known outflow directions. This, in combination with additional cores from the literature observed at similar mass sensitivity and spatial resolution, allowed us to build a sample of 18 protoclusters with luminosities spanning three orders of magnitude. Among the 18 regions, {approx}30% show no signs of fragmentation, while 50% split up into {approx}> 4 millimeter sources. We compiled a list of properties for the 18 massive dense cores, such as bolometric luminosity, total mass, and mean density, and found no correlation of any of these parameters with the fragmentation level. In order to investigate the combined effects of the magnetic field, radiative feedback, and turbulence in the fragmentation process, we compared our observations to radiation magnetohydrodynamic simulations and found that the low-fragmented regions are reproduced well in the magnetized core case, while the highly fragmented regions are consistent with cores where turbulence dominates over the magnetic field. Overall, our study suggests that the fragmentation in massive dense cores could be determined by the initial magnetic field/turbulence balance in each particular core.

  4. High Contrast Imaging with Spitzer: Constraining the Frequency of Giant Planets out to 1000 au Separations

    Durkan, Stephen; Janson, Markus; Carson, Joseph C.

    2016-06-01

    We report results of a re-analysis of archival Spitzer IRAC direct imaging surveys encompassing a variety of nearby stars. Our sample is generated from the combined observations of 73 young stars (median age, distance, spectral type = 85 Myr, 23.3 pc, G5) and 48 known exoplanet host stars with unconstrained ages (median distance, spectral type = 22.6 pc, G5). While the small size of Spitzer provides a lower resolution than 8 m class AO-assisted ground-based telescopes, which have been used for constraining the frequency of 0.5–13 M J planets at separations of 10–102 au, its exquisite infrared sensitivity provides the ability to place unmatched constraints on the planetary populations at wider separations. Here we apply sophisticated high-contrast techniques to our sample in order to remove the stellar point-spread function and to open up sensitivity to planetary mass companions down to 5″ separations. This enables sensitivity to 0.5–13 M J planets at physical separations on the order of 102–103 au, allowing us to probe a parameter space that has not previously been systematically explored to any similar degree of sensitivity. Based on a color and proper motion analysis, we do not record any planetary detections. Exploiting this enhanced survey sensitivity, employing Monte Carlo simulations with a Bayesian approach, and assuming a mass distribution of {dn}/{dm}\\propto {m}-1.31, we constrain (at 95% confidence) a population of 0.5–13 M J planets at separations of 100–1000 au with an upper frequency limit of 9%.

  5. EARLY STAGES OF CLUSTER FORMATION: FRAGMENTATION OF MASSIVE DENSE CORES DOWN TO ∼< 1000 AU

    In order to study the fragmentation of massive dense cores, which constitute the cluster cradles, we observed the continuum at 1.3 mm and the CO (2-1) emission of four massive cores with the Plateau de Bure Interferometer in the most extended configuration. We detected dust condensations down to ∼0.3 M ☉ and separate millimeter sources down to 0.''4 or ∼ 4 millimeter sources. We compiled a list of properties for the 18 massive dense cores, such as bolometric luminosity, total mass, and mean density, and found no correlation of any of these parameters with the fragmentation level. In order to investigate the combined effects of the magnetic field, radiative feedback, and turbulence in the fragmentation process, we compared our observations to radiation magnetohydrodynamic simulations and found that the low-fragmented regions are reproduced well in the magnetized core case, while the highly fragmented regions are consistent with cores where turbulence dominates over the magnetic field. Overall, our study suggests that the fragmentation in massive dense cores could be determined by the initial magnetic field/turbulence balance in each particular core.

  6. An HST Survey for 100–1000 au Companions around Young Stellar Objects in the Orion Molecular Clouds: Evidence for Environmentally Dependent Multiplicity

    Kounkel, M.; Megeath, S. T.; Poteet, C. A.; Fischer, W. J.; Hartmann, L.

    2016-04-01

    We present a near-infrared survey for the visual multiples in the Orion molecular clouds region at separations between 100 and 1000 au. These data were acquired at 1.6 μm with the NICMOS and WFC3 cameras on the Hubble Space Telescope. Additional photometry was obtained for some of the sources at 2.05 μm with NICMOS and in the L‧ band with NSFCAM2 on NASA’s InfraRed Telescope Facility. Toward 129 protostars and 197 pre-main-sequence stars with disks observed with WFC3, we detect 21 and 28 candidate companions between the projected separations of 100–1000 au, of which less than 5 and 8, respectively, are chance line-of-sight coincidences. The resulting companion fraction (CF) after the correction for the line-of-sight contamination is {14.4}-1.3+1.1% for protostars and {12.5}-0.8+1.2% for the pre-main-sequence stars. These values are similar to those found for main-sequence stars, suggesting that there is little variation in the CF with evolution, although several observational biases may mask a decrease in the CF from protostars to the main-sequence stars. After segregating the sample into two populations based on the surrounding surface density of young stellar objects, we find that the CF in the high stellar density regions (ΣYSO > 45 pc‑2) is approximately 50% higher than that found in the low stellar density regions (ΣYSO < 45 pc‑2). We interpret this as evidence for the elevated formation of companions at 100–1000 au in the denser environments of Orion. We discuss possible reasons for this elevated formation.

  7. An HST Survey for 100-1000 AU Companions around Young Stellar Objects in the Orion Molecular Clouds: Evidence for Environmentally Dependent Multiplicity

    Kounkel, M; Poteet, C A; Fischer, W J; Hartmann, L

    2016-01-01

    We present a near-IR survey for the visual multiples in the Orion molecular clouds region at separations between 100 and 1000 AU. These data were acquired at 1.6~$\\mu$m with the NICMOS and WFC3 cameras on the Hubble Space Telescope. Additional photometry was obtained for some of the sources at 2.05~$\\mu$m with NICMOS and in the $L'$-band with NSFCAM2 on the IRTF. Towards 129 protostars and 197 pre-main sequence stars with disks observed with WFC3, we detect 21 and 28 candidate companions between the projected separations of 100---1000 AU, of which less than 5 and 8, respectively, are chance line of sight coincidences. The resulting companion fraction ($CF$) after the correction for the line of sight contamination is 14.4$^{+1.1}_{-1.3}$% for protostars and 12.5$^{+1.2}_{-0.8}$% for the pre-main sequence stars. These values are similar to those found for main sequence stars, suggesting that there is little variation in the $CF$ with evolution, although several observational biases may mask a decrease in the $C...

  8. Relating Biophysical Properties Across Scales

    Flenner, Elijah; Neagu, Adrian; Kosztin, Ioan; Forgacs, Gabor

    2007-01-01

    A distinguishing feature of a multicellular living system is that it operates at various scales, from the intracellular to organismal. Very little is known at present on how tissue level properties are related to cell and subcellular properties. Modern measurement techniques provide quantitative results at both the intracellular and tissue level, but not on the connection between these. In the present work we outline a framework to address this connection. We specifically concentrate on the morphogenetic process of tissue fusion, by following the coalescence of two contiguous multicellular aggregates. The time evolution of this process can accurately be described by the theory of viscous liquids. We also study fusion by Monte Carlo simulations and a novel Cellular Particle Dynamics (CPD) model, which is similar to the earlier introduced Subcellular Element Model (Newman, 2005). Using the combination of experiments, theory and modeling we are able to relate the measured tissue level biophysical quantities to s...

  9. Scale dependence of effective media properties

    For problems where media properties are measured at one scale and applied at another, scaling laws or models must be used in order to define effective properties at the scale of interest. The accuracy of such models will play a critical role in predicting flow and transport through the Yucca Mountain Test Site given the sensitivity of these calculations to the input property fields. Therefore, a research programhas been established to gain a fundamental understanding of how properties scale with the aim of developing and testing models that describe scaling behavior in a quantitative-manner. Scaling of constitutive rock properties is investigated through physical experimentation involving the collection of suites of gas permeability data measured over a range of discrete scales. Also, various physical characteristics of property heterogeneity and the means by which the heterogeneity is measured and described are systematically investigated to evaluate their influence on scaling behavior. This paper summarizes the approach that isbeing taken toward this goal and presents the results of a scoping study that was conducted to evaluate the feasibility of the proposed research

  10. Scale dependence of effective media properties

    For problems where media properties are measured at one scale and applied at another, scaling laws or models must be used in order to define effective properties at the scale of interest. The accuracy of such models will play a critical role in predicting flow and transport through the Yucca Mountain Test Site given the sensitivity of these calculations to the input property fields. Therefore, a research program has been established to gain a fundamental understanding of how properties scale with the aim of developing and testing models that describe scaling behavior in a quantitative manner. Scaling of constitutive rock properties is investigated through physical experimentation involving the collection of suites of gas permeability data measured over a range of discrete scales. Also, various physical characteristics of property heterogeneity and the means by which the heterogeneity is measured and described are systematically investigated to evaluate their influence on scaling behavior. This paper summarizes the approach that is being taken toward this goal and presents the results of a scoping study that was conducted to evaluate the feasibility of the proposed research

  11. Scaling properties of marathon races

    Alvarez-Ramirez, Jose; Rodriguez, Eduardo

    2006-06-01

    Some regularities in popular marathon races are identified in this paper. It is found for high-performance participants (i.e., racing times in the range [2:15,3:15] h), the average velocity as a function of the marathoner's ranking behaves as a power-law, which may be suggesting the presence of critical phenomena. Elite marathoners with racing times below 2:15 h can be considered as outliers with respect to this behavior. For the main marathon pack (i.e., racing times in the range [3:00,6:00] h), the average velocity as a function of the marathoner's ranking behaves linearly. For this racing times, the interpersonal velocity, defined as the difference of velocities between consecutive runners, displays a continuum of scaling behavior ranging from uncorrelated noise for small scales to correlated 1/f-noise for large scales. It is a matter of fact that 1/f-noise is characterized by correlations extended over a wide range of scales, a clear indication of some sort of cooperative effect.

  12. The Relationship Satisfaction scale – Psychometric properties

    Espen Røysamb

    2014-12-01

    Full Text Available The aim of this study was to establish the psychometric properties of the new Relationship Satisfaction (RS scale. Two population based samples were used: The Norwegian Mother and Child Cohort Study (MoBa, N=117,178 and The Quality of Life study (N=347. Convergent and discriminant validity was investigated in relation to the Quality of Marriage Index (QMI, the Satisfaction With Life Scale (SWLS, Relationship Satisfaction of partner, Big Five personality traits (IPIP50 and future relationship dissolution. The full scale with ten items (RS10 and a short version with five items (RS5 showed good psychometric properties. The scale has high internal and test-retest reliability and high structural, convergent, and discriminant validity. Measurement invariance across gender was established. Additionally, predictive validity was evidenced by prediction of future relationship dissolution. We conclude that the RS scale is highly useful as a generic measure of global relationship satisfaction.

  13. Scaling in stratocumulus fields: an emergent property

    Yuan, Tianle

    2015-01-01

    Marine stratocumulus clouds play a critical role in the Earth's climate system. They display an amazing array of complex behaviors at many different spatiotemporal scales. Precipitation in these clouds is in general very light, but it is vital for clouds' systematic evolution and organization. Here we identify areas of high liquid water path within these clouds as potentially precipitating, or pouches. They are breeding grounds for stratocumuli to change their organization form. We show, using different satellite data sets, that the size distribution of these pouches show a universal scaling. We argue that such scaling is an emergent property of the cloud system, which results from numbers interactions at the microscopic scale.

  14. Scaling properties of European research units

    Jamtveit, Bjørn; Jettestuen, Espen; Mathiesen, Joachim

    2009-01-01

    A quantitative characterization of the scale-dependent features of research units may provide important insight into how such units are organized and how they grow. The relative importance of top-down versus bottom-up controls on their growth may be revealed by their scaling properties. Here we show that the number of support staff in Scandinavian research units, ranging in size from 20 to 7,800 staff members, is related to the number of academic staff by a power law. The scaling exponent of ...

  15. Scaling in topological properties of brain networks

    Singh, Soibam Shyamchand; Singh, Khundrakpam Budhachandra; Ishrat, Romana; Sharma, B. Indrajit; Singh, R. K. Brojen

    2015-01-01

    The organization in brain networks shows highly modular features with weak inter-modular interaction. The topology of the networks involves emergence of modules and sub-modules at different levels of constitution governed by fractal laws. The modular organization, in terms of modular mass, inter-modular, and intra-modular interaction, also obeys fractal nature. The parameters which characterize topological properties of brain networks follow one parameter scaling theory in all levels of netwo...

  16. Scale-Free Properties in Traffic System

    LI Ke-Ping

    2006-01-01

    In this work, we propose a new model of evolution networks, which is based on the evolution of the traffic flow. In our method, the network growth does not take into account preferential attachment, and the attachment of new node is independent of the degree of nodes. Our aim is that employing the theory of evolution network, we give a further understanding about the dynamical evolution of the traffic flow. We investigate the probability distributions and scaling properties of the proposed model. The simulation results indicate that in the proposed model, the distribution of the output connections can be well described by scale-free distribution. Moreover, the distribution of the connections is largely related to the traffic flow states, such as the exponential distribution (i.e., the scale-free distribution) and random distribution etc.

  17. Scaling properties of percolation models for multifragmentation

    We have used scaling properties of nuclear multifragmentation, which have been observed with emulsion data, to investigate the properties of some approaches based on percolation. We have studied different percolation models on a cubic lattice and shown that they can rather well reproduce the data except for binary break up. We have described what the mean field approximation would give in this context and showed that it cannot reproduce the experimental results. Most of the paper is focused on the restructured aggregation model introduced earlier which allows to well reproduce the scaling properties observed experimentally. This model has been studied in details and extended to take account of bonds breaking. It is shown that, in some cases, a nucleus can break up in two pieces. This process cannot be obtained in conventional percolation or aggregation but is observed experimentally in the emulsion data. Other features like the dimensionality of the aggregation model, the restructuration of the clusters and a schematic constraint in momentum space have also been investigated. (orig.)

  18. Scaling properties of percolation models for multifragmentation

    Ngo, H.; Ighezou, F.Z.; Desbois, J. (Paris-11 Univ., 91 - Orsay (France). Div. de Physique Theorique); Ngo, C.; Leray, S. (Laboratoire National Saturne, Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)); Zheng, Y.M. (China Center of Advanced Science and Technology, Beijing, BJ (China) Academia Sinica, Beijing (China). Inst. of Atomic Energy)

    1990-09-01

    We have used scaling properties of nuclear multifragmentation, which have been observed with emulsion data, to investigate the properties of some approaches based on percolation. We have studied different percolation models on a cubic lattice and shown that they can rather well reproduce the data except for binary break up. We have described what the mean field approximation would give in this context and showed that it cannot reproduce the experimental results. Most of the paper is focused on the restructured aggregation model introduced earlier which allows to well reproduce the scaling properties observed experimentally. This model has been studied in details and extended to take account of bonds breaking. It is shown that, in some cases, a nucleus can break up in two pieces. This process cannot be obtained in conventional percolation or aggregation but is observed experimentally in the emulsion data. Other features like the dimensionality of the aggregation model, the restructuration of the clusters and a schematic constraint in momentum space have also been investigated. (orig.).

  19. Children's separation anxiety scale (CSAS: psychometric properties.

    Xavier Méndez

    Full Text Available This study describes the psychometric properties of the Children's Separation Anxiety Scale (CSAS, which assesses separation anxiety symptoms in childhood. Participants in Study 1 were 1,908 schoolchildren aged between 8 and 11. Exploratory factor analysis identified four factors: worry about separation, distress from separation, opposition to separation, and calm at separation, which explained 46.91% of the variance. In Study 2, 6,016 children aged 8-11 participated. The factor model in Study 1 was validated by confirmatory factor analysis. The internal consistency (α = 0.82 and temporal stability (r = 0.83 of the instrument were good. The convergent and discriminant validity were evaluated by means of correlations with other measures of separation anxiety, childhood anxiety, depression and anger. Sensitivity of the scale was 85% and its specificity, 95%. The results support the reliability and validity of the CSAS.

  20. Time-scaling properties of city fires

    Highlights: → AnShan city fire sequence is featured by mono- and multi-fractal dynamics. → The monofractal scaling exponent α ∼ 1.0 indicates high degree of time-clusterization, decreasing with the loss. → The city-fire process is highly heterogeneous. → The appearance of the daily oscillation could be connected with the daily cycle of the anthropic activity. - Abstract: Time-scaling scale-invariant approaches have been used to feature the temporal distribution of city fire sequences recorded in the city of AnShan (China). Our findings reveal that the point process of the city fires is a fractal process with a high degree of time-clusterization of the events. The time-clustering phenomenon is visible for timescales larger than few hours. Furthermore, the fire process tends to be less time-clusterized with the increase of the loss. The application of multifractal detrended fluctuation analysis to the series of city-fires has revealed that the sequence is dynamically heterogeneous due to the different long-range time correlation properties for small and large interevent fluctuations.

  1. Outflow structure within 1000 au of high-mass YSOs. I. First results from a combined study of maser and radio continuum emission

    Moscadelli, L.; Sánchez-Monge, Á.; Goddi, C.; Li, J. J.; Sanna, A.; Cesaroni, R.; Pestalozzi, M.; Molinari, S.; Reid, M. J.

    2016-01-01

    Context. In high-mass (≥7 M⊙) star formation (SF) studies, high-angular resolution is crucial for resolving individual protostellar outflows (and possibly accretion disks) from the complex contribution of nearby (high- and low-mass) young stellar objects (YSO). Previous interferometric studies have focused mainly on single objects. Aims: A sensitive survey at high angular resolution is required to investigate outflow processes in a statistically significant sample of high-mass YSOs and on spatial scales relevant to testing theories. Methods: We selected a sample of 40 high-mass YSOs from water masers observed within the BeSSeL Survey. We investigated the 3D velocity and spatial structures of the molecular component of massive outflows at milli-arcsecond angular resolution using multi-epoch Very Long Baseline Array (VLBA) observations of 22 GHz water masers. We also characterize the ionized component of the flows using deep images of the radio continuum emission with resolutions of ~0."2, at 6, 13, and 22 GHz with the Jansky Very Large Array (JVLA). Results: We report the first results obtained for a subset of 11 objects from the sample. The water maser measurements provide us with a very accurate description of the molecular gas kinematics. This in turn enables us to estimate the momentum rate of individual outflows, varying in the range 10-3-100M⊙ yr-1 km s-1, among the highest values reported in the literature. In all the observed objects, the continuum emission at 13 and 22 GHz has a compact structure, with its position coincident with that of the water masers. The 6 GHz continuum consists of either compact components (mostly well aligned with the 13 and/or 22 GHz sources) or extended emission (either highly elongated or approximately spherical), which can be offset by up to a few arcseconds from the water masers. The unresolved continuum emission associated with the water masers likely points to the YSO location. The comparison of the radio continuum

  2. Scale Invariant Properties in Heart Rate Signals

    The rate of heart beat is controlled by autonomic nervous system: accelerated by the sympathetic system and slowed by the parasympathetic system. Scaling properties in heart rate are usually related to the intrinsic dynamics of this physiological regulatory system. The two packages calculating local exponent spectra: Wavelet Transform Modulus Maxima and Multifractal Detrended Fluctuation Analysis (accessible from Physionet home page http://circ.ahajournals.org/cgi/content/full/101/23/e215) are tested, and then used to investigate the spectrum of singularity exponents in series of heart rates obtained from patients suffering from reduced left ventricle systolic function. It occurs that this state of a heart could be connected to some perturbation in the regulatory system, because the heart rate appears to be less controlled than in a healthy human heart. The multifractality in the heart rate signal is weakened: the spectrum is narrower and moved to higher values what indicate the higher activity of the sympatethic nervous system. (author)

  3. Scaling properties of paleomagnetic reversal sequence

    S. S. Ivanov

    1996-01-01

    Full Text Available The history of reversals of main geomagnetic field during last 160 My is analyzed as a sequence of events, presented as a point set on the time axis. Different techniques were applied including the method of boxcounting, dispersion counter-scaling, multifractal analysis and examination of attractor behaviour in multidimensional phase space. The existence of a crossover point at time interval 0.5-1.0 My was clearly identified, dividing the whole time range into two subranges with different scaling properties. The long-term subrange is characterized by monofractal dimension 0.88 and by an attractor, whose correlation dimension converges to 1.0, that provides evidence of a deterministic dynamical system in this subrange, similar to most existing dynamo models. In the short-term subrange the fractal dimension estimated by different methods varies from 0.47 to 0.88 and the dimensionality of the attractor is obtained to be about 3.7. These results are discussed in terms of non-linear superposition of processes in the Earth's geospheres.

  4. Scaling in topological properties of brain networks.

    Singh, Soibam Shyamchand; Khundrakpam, Budhachandra; Reid, Andrew T; Lewis, John D; Evans, Alan C; Ishrat, Romana; Sharma, B Indrajit; Singh, R K Brojen

    2016-01-01

    The organization in brain networks shows highly modular features with weak inter-modular interaction. The topology of the networks involves emergence of modules and sub-modules at different levels of constitution governed by fractal laws that are signatures of self-organization in complex networks. The modular organization, in terms of modular mass, inter-modular, and intra-modular interaction, also obeys fractal nature. The parameters which characterize topological properties of brain networks follow one parameter scaling theory in all levels of network structure, which reveals the self-similar rules governing the network structure. Further, the calculated fractal dimensions of brain networks of different species are found to decrease when one goes from lower to higher level species which implicates the more ordered and self-organized topography at higher level species. The sparsely distributed hubs in brain networks may be most influencing nodes but their absence may not cause network breakdown, and centrality parameters characterizing them also follow one parameter scaling law indicating self-similar roles of these hubs at different levels of organization in brain networks. The local-community-paradigm decomposition plot and calculated local-community-paradigm-correlation co-efficient of brain networks also shows the evidence for self-organization in these networks. PMID:27112129

  5. POLY-SCALE REFINABLE FUNCTION AND THEIR PROPERTIES

    YANG Shou-zhi

    2006-01-01

    Poly-scale refinable function with dilation factor a is introduced. The existence of solution of poly-scale refinable equation is investigated. Specially, necessary and sufficient conditions for the orthonormality of solution function φ of poly-scale refinable equation with integer dilation factor a are established. Some properties of poly-scale refinable function are discussed. Several examples illustrating how to use the method to construct poly-scale refinable function are given.

  6. Large scale properties of the Webgraph

    Donato, D.; Laura, L.; Leonardi, S.; Millozzi, S.

    2004-03-01

    In this paper we present an experimental study of the properties of web graphs. We study a large crawl from 2001 of 200M pages and about 1.4 billion edges made available by the WebBase project at Stanford[CITE]. We report our experimental findings on the topological properties of such graphs, such as the number of bipartite cores and the distribution of degree, PageRank values and strongly connected components.

  7. Electrical properties of random checkerboards at finite scales

    Bharath V. Raghavan

    2015-01-01

    Full Text Available Under investigation is the scale dependent electrical conductivity (and resistivity of two-phase random checkerboards at arbitrary volume fractions and phase contrasts. Using variational principles, rigorous mesoscale bounds are obtained on the electrical properties at finite scales by imposing a boundary condition that is either uniform electric potential or uniform current density. We demonstrate the convergence of these bounds to the effective properties with increasing length scales. This convergence gives rise to the notion of a scalar-valued scaling function that accounts for the statistical nature of the mesoscale responses. A semi-analytical closed form solution for the scaling function is obtained as a function of phase contrast, volume fraction and the mesoscale. Finally, a material scaling diagram is constructed with which the convergence to the effective properties can be assessed for any random checkerboard with arbitrary phase contrast and volume fraction.

  8. Scaling in topological properties of brain networks

    Soibam Shyamchand Singh; Budhachandra Khundrakpam; Andrew T. Reid; Lewis, John D.; Evans, Alan C.; Romana Ishrat; B. Indrajit Sharma; R K Brojen Singh

    2016-01-01

    The organization in brain networks shows highly modular features with weak inter-modular interaction. The topology of the networks involves emergence of modules and sub-modules at different levels of constitution governed by fractal laws that are signatures of self-organization in complex networks. The modular organization, in terms of modular mass, inter-modular, and intra-modular interaction, also obeys fractal nature. The parameters which characterize topological properties of brain networ...

  9. Scale-invariant properties of the APM-Stromlo survey

    Labini, F. Sylos; Montuori, M.

    1997-01-01

    We investigate the statistical properties of the APM-Stromlo redshift survey by using the concepts and methods of modern Statistical Physics. We find that galaxy distribution in this survey exhibits scale invariant properties with fractal dimension $D = 2.1 \\pm 0.1$, up to $\\sim 40 \\hmp$, i.e. the limit of its statistical validity, without any tendency towards homogenization. No intrinsic characteristic scales are definitely found in this galaxy sample. We present several tests to study the s...

  10. Psychometric properties of Frustration Discomfort Scale in a Turkish sample.

    Ozer, Bilge Uzun; Demir, Ayhan; Harrington, Neil

    2012-08-01

    The present study assessed the psychometric properties of the Frustration Discomfort Scale for Turkish college students. The Frustration Discomfort Scale (FDS), Procrastination Assessment Scale-Student, and Rosenberg Self-Esteem Scale were administered to a sample of 171 (98 women, 73 men) Turkish college students. The results of the confirmatory factor analysis yielded fit index values demonstrating viability of the four-dimensional solution as in the original. Findings also revealed that, as predicted, the Discomfort Intolerance subscale of Turkish FDS was most strongly correlated with procrastination. Overall results provided evidence for the factor validity and reliability of the Turkish version of the scale for use in a Turkish population. PMID:23045854

  11. The Chinese Mental Resilience Scale and its psychometric properties.

    Sun, Xin-Yang; Kong, Ling-Ming; Zhang, Qi-Jun; Tao, Feng-Yan; Ma, Ai-Guo; Liu, Yun; Gao, Yu-Fang; Tu, De-Hua; Bai, Xiang-Hui; Su, Wei-Ji; Wang, Li-Jie; Lu, Fang; Song, Wen-Dang; Zhang, Xin-Zhong; Meng, Xin-Zhen; Wang, Yi-Niu; Xie, Hong-Bo; Zhou, Xiao-Dong; Zhang, Li-Yi

    2016-07-01

    This study aimed to develop a Chinese Mental Resilience Scale. A total of 2500 healthy participants, in two representative samples of the Chinese population, were administered the scale. Exploratory factor analysis, confirmatory factor analysis, and correlation analysis were used to obtain the relevant coefficients and verify the reliability and validity of the scale. Five factors were extracted: willpower, family support, optimism and self-confidence, problem solving, and interpersonal interaction, plus a lying subscale, which together accounted for 54 percent of the total variance. The Chinese Mental Resilience Scale demonstrated good psychometric properties. It can be used to evaluate the mental resilience level of general Chinese population. PMID:27357924

  12. Scaling laws and properties of compositional data

    Buccianti, Antonella; Albanese, Stefano; Lima, AnnaMaria; Minolfi, Giulia; De Vivo, Benedetto

    2016-04-01

    Many random processes occur in geochemistry. Accurate predictions of the manner in which elements or chemical species interact each other are needed to construct models able to treat presence of random components. Geochemical variables actually observed are the consequence of several events, some of which may be poorly defined or imperfectly understood. Variables tend to change with time/space but, despite their complexity, may share specific common traits and it is possible to model them stochastically. Description of the frequency distribution of the geochemical abundances has been an important target of research, attracting attention for at least 100 years, starting with CLARKE (1889) and continued by GOLDSCHMIDT (1933) and WEDEPOHL (1955). However, it was AHRENS (1954a,b) who focussed on the effect of skewness distributions, for example the log-normal distribution, regarded by him as a fundamental law of geochemistry. Although modeling of frequency distributions with some probabilistic models (for example Gaussian, log-normal, Pareto) has been well discussed in several fields of application, little attention has been devoted to the features of compositional data. When compositional nature of data is taken into account, the most typical distribution models for compositions are the Dirichlet and the additive logistic normal (or normal on the simplex) (AITCHISON et al. 2003; MATEU-FIGUERAS et al. 2005; MATEU-FIGUERAS and PAWLOWSKY-GLAHN 2008; MATEU-FIGUERAS et al. 2013). As an alternative, because compositional data have to be transformed from simplex space to real space, coordinates obtained by the ilr transformation or by application of the concept of balance can be analyzed by classical methods (EGOZCUE et al. 2003). In this contribution an approach coherent with the properties of compositional information is proposed and used to investigate the shape of the frequency distribution of compositional data. The purpose is to understand data-generation processes

  13. Scale invariant cosmology II: model equations and properties

    Maeder, Andre

    2016-01-01

    We want to establish the basic properties of a scale invariant cosmology, that also accounts for the hypothesis of scale invariance of the empty space at large scales. We write the basic analytical properties of the scale invariant cosmological models. The hypothesis of scale invariance of the empty space at large scale brings interesting simplifications in the scale invariant equations for cosmology. There is one new term, depending on the scale factor of the scale invariant cosmology, that opposes to gravity and favours an accelerated expansion. We first consider a zero-density model and find an accelerated expansion, going like t square. In models with matter present, the displacements due to the new term make a significant contribution Omega_l to the energy-density of the Universe, satisfying an equation of the form Omega_m + Omega_k + Omega_l = 1. Unlike the Friedman's models, there is a whole family of flat models (k=0) with different density parameters Omega_m smaller than 1. We examine the basic relat...

  14. Does Size Really Matter? Landfill Scale Impacts on Property Values

    Lim, Jong Seok; Missios, Paul

    2005-01-01

    The economic advantage of constructing and operating large-scale landfills over small-scale landfills has been used to justify regional landfills as a solution to the municipal waste disposal problem. In addition to the dampening effects on social efforts to divert waste away from landfills, higher external costs of larger landfills may in fact offset the private cost advantages. In this study, the negative effects of a landfill that are capitalized in property values of houses located in the...

  15. Recursive graphs with small-world scale-free properties

    Comellas, Francesc; Fertin, Guillaume; Raspaud, André

    2004-03-01

    We discuss a category of graphs, recursive clique trees, which have small-world and scale-free properties and allow a fine tuning of the clustering and the power-law exponent of their discrete degree distribution. We determine relevant characteristics of those graphs: the diameter, degree distribution, and clustering parameter. The graphs have also an interesting recursive property, and generalize recent constructions with fixed degree distributions.

  16. Scaling properties of sea ice deformation during winter and summer

    Hutchings, J. K.; Heil, P.; Roberts, A.

    2009-12-01

    We investigate sea ice deformation observed with ice drifting buoy arrays during two field campaigns. Ice Station POLarstern [ISPOL], deployed in the western Weddell Sea during November 2004 to January 2005, included a study of small-scale (sub-synoptic) variability in sea ice velocity and deformation using an array of 24 buoys. Upon deployment the ISPOL buoy array measured 70 km in both zonal and meridional extent, and consisted of sub-arrays that resolved sea ice deformation on scales from 10 to 70 km. The Sea Ice Experiment: Dynamic Nature of the Arctic (SEDNA) used two nested arrays of six buoys each as a backbone for the experiment, that were deployed in late March 2007. The two arrays were circular with diameter 140 km and 20 km. ISPOL and SEDNA provide insight into the scaling properties of sea ice deformation over scales of 10 to 200 km during early Astral summer and late Boreal winter. The ISPOL and SEDNA arrays were split into sets of sub-arrays with varying length scales. We find that variance of divergence decreases as the length scale increases. The mean divergence for each length scale set follows a log-linear scaling relationship with length scale. This is an independent verification of a previous result of Marsden, Stern, Lindsay and Weiss (2004). This scaling is indicative of a fractal process. Deformation occurs at linear features (cracks, leads and ridges) in the ice pack, that are distributed with scales that range from meter to hundreds of kilometers in length. The magnitude of deformation at these linear features varies by two orders of magnitude across scales. We demonstrate that the deformation at all these scales is important in the mass balance of sea ice. Which has important implications for the design of sea ice deformation monitoring systems.

  17. Contrasting scaling properties of interglacial and glacial climates

    Shao, Zhi-Gang; Ditlevsen, Peter D.

    2016-03-01

    Understanding natural climate variability is essential for assessments of climate change. This is reflected in the scaling properties of climate records. The scaling exponents of the interglacial and the glacial climates are fundamentally different. The Holocene record is monofractal, with a scaling exponent H~0.7. On the contrary, the glacial record is multifractal, with a significantly higher scaling exponent H~1.2, indicating a longer persistence time and stronger nonlinearities in the glacial climate. The glacial climate is dominated by the strong multi-millennial Dansgaard-Oeschger (DO) events influencing the long-time correlation. However, by separately analysing the last glacial maximum lacking DO events, here we find the same scaling for that period as for the full glacial period. The unbroken scaling thus indicates that the DO events are part of the natural variability and not externally triggered. At glacial time scales, there is a scale break to a trivial scaling, contrasting the DO events from the similarly saw-tooth-shaped glacial cycles.

  18. Scaling properties of crack branching and brittle fragmentation

    Uvarov S.

    2011-01-01

    Full Text Available The present study is focused on the correlation of scaling properties of crack branching and brittle fragmentation with damage accumulation and a change in the fracture mechanism. The experimental results obtained from the glass fragmentation tests indicate that the size distribution of fragments has a fractal character and is described by a power law.

  19. Homework Emotion Regulation Scale: Psychometric Properties for Middle School Students

    Xu, Jianzhong; Fan, Xitao; Du, Jianxia

    2016-01-01

    The goal of the present investigation is to evaluate the psychometric properties of the Homework Emotion Regulation Scale (HERS) using 796 middle school students in China. Confirmatory factor analyses (CFAs) supported the existence of two distinct yet related subscales for the HERS: Emotion Management and Cognitive Reappraisal. Concerning the…

  20. Psychometric Properties of the Commitment to Physical Activity Scale

    DeBate, Rita DiGioacchino; Huberty, Jennifer; Pettee, Kelley

    2009-01-01

    Objective: To assess psychometric properties of the Commitment to Physical Activity Scale (CPAS). Methods: Girls in third to fifth grades (n = 932) completed the CPAS before and after a physical activity intervention. Psychometric measures included internal consistency, factor analysis, and concurrent validity. Results: Three CPAS factors emerged:…

  1. Scaling relations for galaxy clusters: properties and evolution

    Giodini, S; Pointecouteau, E; Ettori, S; Reiprich, T H; Hoekstra, H

    2013-01-01

    Well-calibrated scaling relations between the observable properties and the total masses of clusters of galaxies are important for understanding the physical processes that give rise to these relations. They are also a critical ingredient for studies that aim to constrain cosmological parameters using galaxy clusters. For this reason much effort has been spent during the last decade to better understand and interpret relations of the properties of the intra-cluster medium. Improved X-ray data have expanded the mass range down to galaxy groups, whereas SZ surveys have openened a new observational window on the intracluster medium. In addition,continued progress in the performance of cosmological simulations has allowed a better understanding of the physical processes and selection effects affecting the observed scaling relations. Here we review the recent literature on various scaling relations, focussing on the latest observational measurements and the progress in our understanding of the deviations from self...

  2. Scaling Properties of Force Networks for Compressed Particulate Systems

    Kovalcinova, Lenka; Kondic, Lou

    2015-01-01

    We consider, computationally and experimentally, the scaling properties of force networks in the systems of circular particles exposed to compression in two spatial dimensions. The simulations consider polydisperse and monodisperse particles, both frictional and frictionless, and in experiments we use monodisperse and bidisperse particles. While for some of the considered systems we observe consistent scaling exponents describing the behavior of the force networks, we find that this behavior is it not universal. In particular, monodisperse frictionless systems that partially crystallize under compression, show scaling properties that are significantly different compared to the other considered systems. The findings of non-universality are confirmed by explicitly computing fractal dimension for the considered systems. The results of physical experiments are consistent with the results obtained in simulations of frictional particles.

  3. Scaling properties of dislocation simulations in the similitude regime

    Dislocation systems exhibit well-known scaling properties such as the Taylor relationship between flow stress and dislocation density, and the ‘law of similitude’ linking the flow stress to the characteristic wavelength of dislocation patterns. Here, we discuss the origin of these properties, which can be related to generic invariance properties of the equations of evolution of discrete dislocation systems, and their implications for a wide class of models of dislocation microstructure evolution. We demonstrate that under certain conditions dislocation simulations carried out at different stress, dislocation density and strain rate can be considered to be equivalent, and we study the range of deformation conditions (‘similitude regime’) over which this equivalence can be expected to hold. In addition, we discuss restrictions imposed by the stated invariance properties for density-based, non-local or stochastic models of dislocation microstructure evolution, and for dislocation patterns and size effects. (paper)

  4. PROPERTIES IMPORTANT TO MIXING FOR WTP LARGE SCALE INTEGRATED TESTING

    Koopman, D.; Martino, C.; Poirier, M.

    2012-04-26

    Large Scale Integrated Testing (LSIT) is being planned by Bechtel National, Inc. to address uncertainties in the full scale mixing performance of the Hanford Waste Treatment and Immobilization Plant (WTP). Testing will use simulated waste rather than actual Hanford waste. Therefore, the use of suitable simulants is critical to achieving the goals of the test program. External review boards have raised questions regarding the overall representativeness of simulants used in previous mixing tests. Accordingly, WTP requested the Savannah River National Laboratory (SRNL) to assist with development of simulants for use in LSIT. Among the first tasks assigned to SRNL was to develop a list of waste properties that matter to pulse-jet mixer (PJM) mixing of WTP tanks. This report satisfies Commitment 5.2.3.1 of the Department of Energy Implementation Plan for Defense Nuclear Facilities Safety Board Recommendation 2010-2: physical properties important to mixing and scaling. In support of waste simulant development, the following two objectives are the focus of this report: (1) Assess physical and chemical properties important to the testing and development of mixing scaling relationships; (2) Identify the governing properties and associated ranges for LSIT to achieve the Newtonian and non-Newtonian test objectives. This includes the properties to support testing of sampling and heel management systems. The test objectives for LSIT relate to transfer and pump out of solid particles, prototypic integrated operations, sparger operation, PJM controllability, vessel level/density measurement accuracy, sampling, heel management, PJM restart, design and safety margin, Computational Fluid Dynamics (CFD) Verification and Validation (V and V) and comparison, performance testing and scaling, and high temperature operation. The slurry properties that are most important to Performance Testing and Scaling depend on the test objective and rheological classification of the slurry (i

  5. Properties Important To Mixing For WTP Large Scale Integrated Testing

    Large Scale Integrated Testing (LSIT) is being planned by Bechtel National, Inc. to address uncertainties in the full scale mixing performance of the Hanford Waste Treatment and Immobilization Plant (WTP). Testing will use simulated waste rather than actual Hanford waste. Therefore, the use of suitable simulants is critical to achieving the goals of the test program. External review boards have raised questions regarding the overall representativeness of simulants used in previous mixing tests. Accordingly, WTP requested the Savannah River National Laboratory (SRNL) to assist with development of simulants for use in LSIT. Among the first tasks assigned to SRNL was to develop a list of waste properties that matter to pulse-jet mixer (PJM) mixing of WTP tanks. This report satisfies Commitment 5.2.3.1 of the Department of Energy Implementation Plan for Defense Nuclear Facilities Safety Board Recommendation 2010-2: physical properties important to mixing and scaling. In support of waste simulant development, the following two objectives are the focus of this report: (1) Assess physical and chemical properties important to the testing and development of mixing scaling relationships; (2) Identify the governing properties and associated ranges for LSIT to achieve the Newtonian and non-Newtonian test objectives. This includes the properties to support testing of sampling and heel management systems. The test objectives for LSIT relate to transfer and pump out of solid particles, prototypic integrated operations, sparger operation, PJM controllability, vessel level/density measurement accuracy, sampling, heel management, PJM restart, design and safety margin, Computational Fluid Dynamics (CFD) Verification and Validation (V and V) and comparison, performance testing and scaling, and high temperature operation. The slurry properties that are most important to Performance Testing and Scaling depend on the test objective and rheological classification of the slurry (i

  6. The scaling properties of dynamical fluctuations in temporal networks

    Chi, Liping

    2015-01-01

    The factorial moments analyses are performed to study the scaling properties of the dynamical fluctuations of contacts and nodes in temporal networks based on empirical data sets. The intermittent behaviors are observed in the fluctuations for all orders of the moments. It indicates that the interaction has self-similarity structure in time interval and the fluctuations are not purely random but dynamical and correlated. The scaling exponents for contacts in Prostitution data and nodes in Conference data are very close to that for 2D Ising model undergoing a second-order phase transition.

  7. Semi industrial scale RVNRL preparation, products manufacturing and properties

    Zin, Wan Manshol Bin W.

    1998-06-01

    Natural rubber latex vulcanisation by radiation aims towards the preparation of prevulcanised natural rubber latex in the name of RVNRL for use to produce chemical-free and environment-friendly latex products. Scale up RVNRL preparation is proven possible when a semi-commercial latex irradiator was commissioned in MINT in March 1996. The plant is designed to irradiate up to 6 000 cubic meters per annum of natural rubber latex. RVNRL has the required properties and successfully used on industrial scale production of quality gloves and balloons.

  8. Psychometric Properties of the Scale for Suicide Ideation in China

    Jie ZHANG; Brown, Gregory K.

    2007-01-01

    The Chinese version of Scale for Suicide Ideation (SSI; Beck, Kovacs, & Weissman, 1979) was examined with high school students (n = 292) in rural China, Results indicated that the SSI had high internal reliability and high item-total correlations. The SSI was highly correlated with measures of trait anxiety, hopelessness, and favorable attitude towards suicide. These findings indicated that the Chinese version of the SSI has excellent psychometric properties for measuring suicidal ideation in...

  9. Scaling of Folding Properties in Go Models of Proteins

    Cieplak, Marek; Xuan Hoang, Trinh

    2000-01-01

    Insights about scaling of folding properties of proteins are obtained bystudying folding in heteropolymers described by Go-like Hamiltonians. Bothlattice and continuum space models are considered. In the latter case, themonomer-monomer interactions correspond to the Lennard-Jones potential.Several statistical ensembles of the two- and three-dimensional targetnative conformations are considered. Among them are maximally compactconformations which are confined to a lattice and those which are o...

  10. Universal scaling properties of extremal cohesive holographic phases

    Goutéraux, B. [Nordita, KTH Royal Institute of Technology and Stockholm University,Roslagstullsbacken 23, SE-106 91 Stockholm (Sweden)

    2014-01-16

    We show that strongly-coupled, translation-invariant holographic IR phases at finite density can be classified according to the scaling behaviour of the metric, the electric potential and the electric flux introducing four critical exponents, independently of the details of the setup. Solutions fall into two classes, depending on whether they break relativistic symmetry or not. The critical exponents determine key properties of these phases, like thermodynamic stability, the (ir)relevant deformations around them, the low-frequency scaling of the optical conductivity and the nature of the spectrum for electric perturbations. We also study the scaling behaviour of the electric flux through bulk minimal surfaces using the Hartnoll-Radicevic order parameter, and characterize the deviation from the Ryu-Takayanagi prescription in terms of the critical exponents.

  11. Universal scaling properties of extremal cohesive holographic phases

    We show that strongly-coupled, translation-invariant holographic IR phases at finite density can be classified according to the scaling behaviour of the metric, the electric potential and the electric flux introducing four critical exponents, independently of the details of the setup. Solutions fall into two classes, depending on whether they break relativistic symmetry or not. The critical exponents determine key properties of these phases, like thermodynamic stability, the (ir)relevant deformations around them, the low-frequency scaling of the optical conductivity and the nature of the spectrum for electric perturbations. We also study the scaling behaviour of the electric flux through bulk minimal surfaces using the Hartnoll-Radicevic order parameter, and characterize the deviation from the Ryu-Takayanagi prescription in terms of the critical exponents

  12. Scaling Properties in Time-Varying Networks with Memory

    Kim, Hyewon; Jeong, Hawoong

    2015-01-01

    The formation of network structure is influenced by individual node's activity and its memory. Usually activity can be interpreted as the inherent property of node and memory can be represented by the interaction strength among nodes. In our study, we define the activity through the appearance pattern in the time-aggregated network representation, and quantify the memory through the contact pattern of empirical temporal networks. To address the role of activity and memory in epidemics on temporal networks, we propose temporal-pattern coarsening of activity-driven growing networks with memory. In particular, we focus on the relation between coarsening time scale and spreading dynamics in the context of dynamic scaling and finite-size scaling. Finally, we discuss the universality issue of spreading dynamics on time-varying networks for various memory causality aspects.

  13. Properties of Cosmic Shock Waves in Large Scale Structure Formation

    Miniati, F; Kang, H; Jones, T W; Cen, R; Ostriker, J P; Miniati, Francesco; Ryu, Dongsu; Kang, Hyesung; Cen, Renyue; Ostriker, Jeremiah P.

    2000-01-01

    We have examined the properties of shock waves in simulations of large scale structure formation for two cosmological scenarios (a SCDM and a LCDM with Omega =1). Large-scale shocks result from accretion onto sheets, filaments and Galaxy Clusters (GCs) on a scale of circa 5 Mpc/h in both cases. Energetic motions, both residual of past accretion history and due to current asymmetric inflow along filaments, generate additional, common shocks on a scale of about 1 Mpc/h, which penetrate deep inside GCs. Also collisions between substructures inside GCs form merger shocks. Consequently, the topology of the shocks is very complex and highly connected. During cosmic evolution the comoving shock surface density decreases, reflecting the ongoing structure merger process in both scenarios. Accretion shocks have very high Mach numbers (10-10^3), when photo-heating of the pre-shock gas is not included. The typical shock speed is of order v_{sh}(z) =H(z)lambda_{NL}(z), with lambda_{NL}(z) the wavelength scale of the nonli...

  14. Psychometric properties of the Interaction on Supervised Classes Scale (ISCS

    Adrián Pastor-Barceló

    2016-06-01

    Full Text Available Purpose: This research focuses on the construction and validation of a scale designed to assess the quality of the supervised classes: Interaction on Supervised Classes Scale (ISCS. Design/methodology/approach: This is a descriptive correlational study. For the construction of the scale three phases were performed in which different experts assessed the adequacy of the items. Finally, the psychometric properties of the final version were studied in a sample of 314 consumers (69.1% women aged between 18 and 77 with an average of 39.33 years (SD=12.25. Findings: The scale presents adequate validity and reliability, being a useful tool for measuring the interaction in Supervised Classes. Research limitations/implications: The sampling, non-probabilistic or convenience, have taken the sample of a unique sports facility and the small sample size. Practical implications: The ISCS allows managers to receive better feedback, allowing them to obtain deeper insight into the quality and satisfaction of the service. According to its results, the managers may implement different strategies to improve quality in a key service within sports centers. Originality/value: For the first time the interaction between customers and between customers and employees is evaluated both inside and outside the center, a topic that had not yet been studied in the scientific literature. The scale can be applied to any type of directed activity, and will allow a greater understanding of the quality of service.

  15. Scaling properties of superoscillations and the extension to periodic signals

    Tang, Eugene; Garg, Lovneesh; Kempf, Achim

    2016-08-01

    Superoscillatory wave forms, i.e., waves that locally oscillate faster than their highest Fourier component, possess unusual properties that make them of great interest from quantum mechanics to signal processing. However, the more pronounced the desired superoscillatory behavior is to be, the more difficult it becomes to produce, or even only calculate, such highly fine-tuned wave forms in practice. Here, we investigate how this sensitivity to preparation errors scales for a method for constructing superoscillatory functions which is optimal in the sense that it minimizes the energetic expense. We thereby also arrive at very accurate approximations of functions which are so highly superoscillatory that they cannot be calculated numerically. We then investigate to what extent the scaling and sensitivity results for superoscillatory functions on the real line extend to the experimentally important case of superoscillatory functions that are periodic.

  16. ECG scaling properties of cardiac arrhythmias using detrended fluctuation analysis

    We applied detrended fluctuation analysis to characterize at very short time scales during episodes of cardiac arrhythmias the raw electrocardiogram (ECG) waveform, aiming to get a global insight into its dynamical behaviour in patients who experienced sudden death. We found that in 15 recordings involving different types of arrhythmias (taken from PhysioNet's Sudden Cardiac Death Holter Database), the ECG waveform, besides showing a less-random dynamics, becomes more regular during bigeminy, ventricular tachycardia or even atrial fibrillation and ventricular fibrillation. The ECG waveform scaling properties thus suggest that reduced complexity dominates the underlying mechanisms of arrhythmias. Among other explanations, this may result from shorted or restricted (i.e. less diverse) pathways of conduction of the electrical activity within ventricles

  17. Scaling Properties of Superoscillations and the Extension to Periodic Signals

    Tang, Eugene; Kempf, Achim

    2015-01-01

    Superoscillatory wave forms, i.e., waves that locally oscillate faster than their highest Fourier component, possess unusual properties that make them of great interest from quantum mechanics to signal processing. However, the more pronounced the desired superoscillatory behavior is to be, the more difficult it becomes to produce, or even only calculate, such highly fine-tuned wave forms in practice. Here, we investigate how this sensitivity to preparation errors scales for a method for constructing superoscillatory functions which is optimal in the sense that it minimizes the energetic expense. We thereby also arrive at very accurate approximations of functions which are so highly superoscillatory that they cannot be calculated numerically. We then investigate to what extent the scaling and sensitivity results for superoscillatory functions on the real line extend to the experimentally important case of superoscillatory functions that are periodic.

  18. Psychometric Properties of the Adolescent Sleep Hygiene Scale (ASHS)

    Storfer-Isser, A; LeBourgeois, MK; Harsh, J.; Tompsett, CJ; Redline, S.

    2013-01-01

    This study evaluated the psychometric properties of the Adolescent Sleep Hygiene Scale (ASHS), a self-report measure assessing sleep practices theoretically important for optimal sleep. Data were collected on a community sample of 514 adolescents (16-19 years; 17.7±0.4 years; 50% female) participating in the late adolescent examination of a longitudinal study on sleep and health. Self-reports of sleep hygiene and daytime sleepiness, caretaker-reports of behavior, and sleep-wake estimation on ...

  19. Psychometric Properties of the Dutch Rosenberg Self-Esteem Scale

    Erik Franck

    2008-01-01

    Full Text Available Interest in self-esteem has been fuelled by the suggestion that level of self-esteem is associated with psychological well-being. In the present study, we translated the Rosenberg Self-Esteem Scale (RSES into the Dutch language and evaluated its psychometric properties in a sample of 442 adults. The results of both exploratory and confirmatory factor analyses confirmed that a single-factor solution provides the best fit. In addition, the Dutch RSES showed high internal consistency as well as high congruent validity. Overall, these findings support the usefulness of the Dutch RSES as a measure for global self-esteem.

  20. Psychometric Properties of the Dutch Rosenberg Self-Esteem Scale

    Erik Franck; Rudi De Raedt; Catherine Barbez; Yves Rosseel

    2008-01-01

    Interest in self-esteem has been fuelled by the suggestion that level of self-esteem is associated with psychological well-being. In the present study, we translated the Rosenberg Self-Esteem Scale (RSES) into the Dutch language and evaluated its psychometric properties in a sample of 442 adults. The results of both exploratory and confirmatory factor analyses confirmed that a single-factor solution provides the best fit. In addition, the Dutch RSES showed high internal consistency as well as...

  1. The psychometric properties of the Schutte emotional intelligence scale

    Cara S. Jonker; Christel Vosloo

    2008-01-01

    the objective of this study was to investigate the psychometric properties of the Schutte Emotional Intelligence Scale (SEiS). the psychometric soundness of the SEiS was tested. A cross-sectional survey design was used for this study. A sample (n = 341) was taken from Economical Science students from a higher-education institution. The results obtained using the cross-sectional design supported a six- dimensional factor structure of the SEiS. the six factors are Positive Affect, Emotion-...

  2. Mechanical Properties of Materials with Nanometer Scale Microstructures

    William D. Nix

    2004-10-31

    We have been engaged in research on the mechanical properties of materials with nanometer-scale microstructural dimensions. Our attention has been focused on studying the mechanical properties of thin films and interfaces and very small volumes of material. Because the dimensions of thin film samples are small (typically 1 mm in thickness, or less), specialized mechanical testing techniques based on nanoindentation, microbeam bending and dynamic vibration of micromachined structures have been developed and used. Here we report briefly on some of the results we have obtained over the past three years. We also give a summary of all of the dissertations, talks and publications completed on this grant during the past 15 years.

  3. Kpc-scale Properties of Emission-line Galaxies

    Hemmati, Shoubaneh; Mobasher, Bahram; Nayyeri, Hooshang; Ferguson, Henry C; Guo, Yicheng; Koekemoer, Anton M; Koo, David C; Papovich, Casey

    2014-01-01

    We perform a detailed study of the resolved properties of emission-line galaxies at kpc-scale to investigate how small-scale and global properties of galaxies are related. 119 galaxies with high-resolution Keck/DEIMOS spectra are selected to cover a wide range in morphologies over the redshift range 0.2

  4. Matching spatial property rights fisheries with scales of fish dispersal.

    White, Crow; Costello, Christopher

    2011-03-01

    Regulation of fisheries using spatial property rights can alleviate competition for high-value patches that hinders economic efficiency in quota-based, rights-based, and open-access management programs. However, efficiency gains erode when delineation of spatial rights constitutes incomplete ownership of the resource, thereby degrading its local value and promoting overexploitation. Incomplete ownership may be particularly prevalent in the spatial management of mobile fishery species. We developed a game-theoretic bioeconomic model of spatial property rights representing territorial user rights fisheries (TURF) management of nearshore marine fish and invertebrate species with mobile adult and larval life history stages. Strategic responses by fisheries in neighboring management units result in overexploitation of the stock and reduced yields for each fishery compared with those attainable without resource mobility or with coordination or sole control in fishing effort. High dispersal potential of the larval stage, a common trait among nearshore fishery species, coupled with scaling of management units to only capture adult mobility, a common characteristic of many nearshore TURF programs, in particular substantially reduced stock levels and yields. In a case study of hypothetical TURF programs of nearshore fish and invertebrate species, management units needed to be tens of kilometers in alongshore length to minimize larval export and generate reasonable returns to fisheries. Cooperation and quota regulations represent solutions to the problem that need to be quantified in cost and integrated into the determination of the acceptability of spatial property rights management of fisheries. PMID:21563568

  5. Arecibo Multi-Epoch HI Absorption Measurements Against Pulsars: Tiny-Scale Atomic Structure

    Stanimirovic, S; Pei, Z; Tuttle, K; Green, J T

    2010-01-01

    We present results from multi-epoch neutral hydrogen (HI) absorption observations of six bright pulsars with the Arecibo telescope. Moving through the interstellar medium (ISM) with transverse velocities of 10--150 AU/yr, these pulsars have swept across 1--200 AU over the course of our experiment, allowing us to probe the existence and properties of the tiny scale atomic structure (TSAS) in the cold neutral medium (CNM). While most of the observed pulsars show no significant change in their HI absorption spectra, we have identified at least two clear TSAS-induced opacity variations in the direction of B1929+10. These observations require strong spatial inhomogeneities in either the TSAS clouds' physical properties themselves or else in the clouds' galactic distribution. While TSAS is occasionally detected on spatial scales down to 10 AU, it is too rare to be characterized by a spectrum of turbulent CNM fluctuations on scales of 10-1000 AU, as previously suggested by some work. In the direction of B1929+10, an...

  6. The psychometric properties of the Schutte Emotional Intelligence Scale

    Cara S. Jonker

    2008-11-01

    Full Text Available the objective of this study was to investigate the psychometric properties of the Schutte Emotional Intelligence Scale (SEiS. the psychometric soundness of the SEiS was tested. A cross-sectional survey design was used for this study. A sample (n = 341 was taken from Economical Science students from a higher-education institution. The results obtained using the cross-sectional design supported a six- dimensional factor structure of the SEiS. the six factors are Positive Affect, Emotion-Others, happy Emotions, Emotions-Own, Non-verbal Emotions and Emotional Management. A multi-analysis of variance (MANOVA was used to determine differences in terms of biographical data. the results indicated signifcant differences between gender and language groups.

  7. Scaling properties of phase-change line memory

    Du Xiao-Feng; Song San-Nian; Song Zhi-Tang; Liu Wei-Li; Lü Shi-Long; Gu Yi-Feng; Xue Wei-Jia; Xi Wei

    2012-01-01

    Phase-change line memory cells with different line widths are fabricated using focused-ion-beam deposited C-Pt as a hard mask.The electrical performance of these memory devices was characterized.The current-voltage (I-V) and resistance-voltage (R-V) characteristics demonstrate that the power consumption decreases with the width of the phase-change line.A three-dimensional simulation is carried out to further study the scaling properties of the phase-change line memory.The results show that the resistive amorphous (RESET) power consumption is proportional to the cross-sectional area of the phase-change line,but increases as the line length decreases.

  8. Multiwavelength and parsec-scale properties of extragalactic jets

    Cornelia, Müller

    2016-01-01

    Extragalactic jets originating from the central supermassive black holes of active galaxies are powerful, highly relativistic plasma outflows, emitting light from the radio up to the gamma-ray regime. The details of their formation, composition and emission mechanisms are still not completely clear. The combination of high-resolution observations using very long baseline interferometry (VLBI) and multiwavelength monitoring provides the best insight into these objects. Here, such a combined study of sources of the TANAMI sample is presented, investigating the parsec-scale and high-energy properties. The TANAMI program is a multiwavelength monitoring program of a sample of the radio and gamma-ray brightest extragalactic jets in the southern sky, below -30deg declination. We obtain the first-ever VLBI images for most of the sources, providing crucial information on the jet kinematics and brightness distribution at milliarcsecond resolution. Two particular sources are discussed in detail: PMN J1603-4904, which ca...

  9. Weighted Scale-Free Network Properties of Ecological Network

    We investigate the scale-free network properties of the bipartite ecological network, in particular, the plant-pollinator network. In plant-pollinator network, the pollinators visit the plant to get the nectars. In contrast to the other complex network, the plant-pollinator network has not only the trophic relationships among the interacting partners but also the complexities of the coevolutionary effects. The interactions between the plant and pollinators are beneficial relations. The plant-pollinator network is a bipartite and weighted network. The networks have two types of the nodes: plant and pollinator. We consider the visiting frequency of a pollinator to a plant as the weighting value of the link. We defined the strength of a node as the sum of the weighting value of the links. We reported the cumulative distribution function (CDF) of the degree and the strength of the plant-pollinator network. The CDF of the plants followed stretched exponential functions for both degree and strength, but the CDF of the pollinators showed the power law for both degree and strength. The average strength of the links showed the nonlinear dependence on the degree of the networks.

  10. Synthetic melanin films: Assembling mechanisms, scaling behavior, and structural properties

    Lorite, Gabriela S.; Coluci, Vitor R.; da Silva, Maria Ivonete N.; Dezidério, Shirlei N.; Graeff, Carlos Frederico O.; Galva~O, Douglas S.; Cotta, Mônica A.

    2006-06-01

    In this work we report on the surface characterization of melanin thin films prepared using both water-based and organic solvent-based melanin syntheses. Atomic force microscopy (AFM) analysis of these films suggests that the organic solvent synthesis provides relatively planar basic melanin structures; these basic structures generate surface steps with height in the range of 2-3 nm and small tendency to form larger aggregates. The scaling properties obtained from the AFM data were used to infer the assembling mechanisms of these thin films which depend on the solvent used for melanin synthesis. The behavior observed in organic solvent-based melanin suggests a diffusion-limited aggregation process. Thus films with good adhesion to the substrate and smoother morphologies than water-prepared melanin films are obtained. Electronic structure calculations using a conductorlike screening model were also performed in order to elucidate the microscopic processes of thin film formation. Our results suggest that the agglomerates observed in hydrated samples originate from reaction with water at specific locations on the surface most likely defects on the planar structure.

  11. What exactly are the properties of scale-free and other networks?

    Judd, Kevin; Small, Michael; Stemler, Thomas

    2013-01-01

    The concept of scale-free networks has been widely applied across natural and physical sciences. Many claims are made about the properties of these networks, even though the concept of scale-free is often vaguely defined. We present tools and procedures to analyse the statistical properties of networks defined by arbitrary degree distributions and other constraints. Doing so reveals the highly likely properties, and some unrecognised richness, of scale-free networks, and casts doubt on some p...

  12. Scaling soil hydraulic properties: concepts and a research example

    Scale issues remain central to hydrological science, and targeted land management decisions depend on predictions of space-time process interactions in complex terrain. Spatial variability in soils above the measurement scale must be quantified and typically scaled up to determine “effective” hydrau...

  13. Calculation of large scale relative permeabilities from stochastic properties of the permeability field and fluid properties

    Lenormand, R.; Thiele, M.R. [Institut Francais du Petrole, Rueil Malmaison (France)

    1997-08-01

    The paper describes the method and presents preliminary results for the calculation of homogenized relative permeabilities using stochastic properties of the permeability field. In heterogeneous media, the spreading of an injected fluid is mainly sue to the permeability heterogeneity and viscosity fingering. At large scale, when the heterogeneous medium is replaced by a homogeneous one, we need to introduce a homogenized (or pseudo) relative permeability to obtain the same spreading. Generally, is derived by using fine-grid numerical simulations (Kyte and Berry). However, this operation is time consuming and cannot be performed for all the meshes of the reservoir. We propose an alternate method which uses the information given by the stochastic properties of the field without any numerical simulation. The method is based on recent developments on homogenized transport equations (the {open_quotes}MHD{close_quotes} equation, Lenormand SPE 30797). The MHD equation accounts for the three basic mechanisms of spreading of the injected fluid: (1) Dispersive spreading due to small scale randomness, characterized by a macrodispersion coefficient D. (2) Convective spreading due to large scale heterogeneities (layers) characterized by a heterogeneity factor H. (3) Viscous fingering characterized by an apparent viscosity ration M. In the paper, we first derive the parameters D and H as functions of variance and correlation length of the permeability field. The results are shown to be in good agreement with fine-grid simulations. The are then derived a function of D, H and M. The main result is that this approach lead to a time dependent . Finally, the calculated are compared to the values derived by history matching using fine-grid numerical simulations.

  14. USING ENSEMBLE PREDICTIONS TO SIMULATE FIELD-SCALE SOIL WATER TIME SERIES WITH UPSCALED AND DOWNSCALED SOIL HYDRAULIC PROPERTIES

    Simulations of soil water flow require measurements of soil hydraulic properties which are particularly difficult at field scale. Laboratory measurements provide hydraulic properties at scales finer than the field scale, whereas pedotransfer functions (PTFs) integrate information on hydraulic prope...

  15. Fixed point SU(3) gauge actions: scaling properties and glueballs

    We present a new parametrization of a SU(3) fixed point (FP) gauge action using smeared ('fat') gauge links. We report on the scaling behaviour of the FP action on coarse lattices by means of the static quark-antiquark potential, the hadronic scale r0, the string tension σ and the critical temperature Tc of the deconfining phase transition. In addition, we investigate the low lying glueball masses where we observe no scaling violations within the statistical errors

  16. Serbian translation of the 20-item toronto alexithymia scale: Psychometric properties and the new methodological approach in translating scales

    Trajanović Nikola N.

    2013-01-01

    Full Text Available Introduction. Since inception of the alexithymia construct in 1970’s, there has been a continuous effort to improve both its theoretical postulates and the clinical utility through development, standardization and validation of assessment scales. Objective. The aim of this study was to validate the Serbian translation of the 20-item Toronto Alexithymia Scale (TAS-20 and to propose a new method of translation of scales with a property of temporal stability. Methods. The scale was expertly translated by bilingual medical professionals and a linguist, and given to a sample of bilingual participants from the general population who completed both the English and the Serbian version of the scale one week apart. Results. The findings showed that the Serbian version of the TAS-20 had a good internal consistency reliability regarding total scale (α=0.86, and acceptable reliability of the three factors (α=0.71-0.79. Conclusion. The analysis confirmed the validity and consistency of the Serbian translation of the scale, with observed weakness of the factorial structure consistent with studies in other languages. The results also showed that the method of utilizing a self-control bilingual subject is a useful alternative to the back-translation method, particularly in cases of linguistically and structurally sensitive scales, or in cases where a larger sample is not available. This method, dubbed as ‘forth-translation’, could be used to translate psychometric scales measuring properties which have temporal stability over the period of at least several weeks.

  17. The Alzheimer's Disease Knowledge Scale: Development and Psychometric Properties

    Carpenter, Brian D.; Balsis, Steve; Otilingam, Poorni G.; Hanson, Priya K.; Gatz, Margaret

    2009-01-01

    Purpose: This study provides preliminary evidence for the acceptability, reliability, and validity of the new Alzheimer's Disease Knowledge Scale (ADKS), a content and psychometric update to the Alzheimer's Disease Knowledge Test. Design and Methods: Traditional scale development methods were used to generate items and evaluate their psychometric…

  18. Multiscale properties of DNA primary structure: cross-scale correlations

    Cross-scale correlations of wavelet coefficients of the DNA coding sequences are calculated and compared to that of the generated random sequence of the same length. The coding sequences are shown to have strong correlation between large and small scale structures, while random sequences have not

  19. Laboratory investigation of constitutive property up-scaling in volcanic tuffs

    One of the critical issues facing the Yucca Mountain site characterization and performance assessment programs is the manner in which property up-scaling is addressed. Property up-scaling becomes an issue whenever heterogeneous media properties are measured at one scale but applied at another. A research program has been established to challenge current understanding of property up-scaling with the aim of developing and testing improved models that describe up-scaling behavior in a quantitative manner. Up-scaling of constitutive rock properties is investigated through physical experimentation involving the collection of suites of gas-permeability data measured over a range of discrete scales. To date, up-scaling studies have been performed on a series of tuff and sandstone (used as experimental controls) blocks. Samples include a welded, anisotropic tuff (Tiva Canyon Member of the Paintbrush Tuff, upper cliff microstratigraphic unit), and a moderately welded tuff (Tiva Canyon Member of the Paintbrush Tuff, Caprock microstratigraphic unit). A massive fluvial sandstone (Berea Sandstone) was also investigated as a means of evaluating the experimental program and to provide a point of comparison for the tuff data. Because unsaturated flow is of prime interest to the Yucca Mountain Program, scoping studies aimed at investigating the up-scaling of hydraulic properties under various saturated conditions were performed to compliment these studies of intrinsic permeability. These studies focused on matrix sorptivity, a constitutive property quantifying the capillarity of a porous medium. 113 refs

  20. Laboratory investigation of constitutive property up-scaling in volcanic tuffs

    Tidwell, V.C. [Sandia National Labs., Albuquerque, NM (United States). Geohydrology Dept.

    1996-08-01

    One of the critical issues facing the Yucca Mountain site characterization and performance assessment programs is the manner in which property up-scaling is addressed. Property up-scaling becomes an issue whenever heterogeneous media properties are measured at one scale but applied at another. A research program has been established to challenge current understanding of property up-scaling with the aim of developing and testing improved models that describe up-scaling behavior in a quantitative manner. Up-scaling of constitutive rock properties is investigated through physical experimentation involving the collection of suites of gas-permeability data measured over a range of discrete scales. To date, up-scaling studies have been performed on a series of tuff and sandstone (used as experimental controls) blocks. Samples include a welded, anisotropic tuff (Tiva Canyon Member of the Paintbrush Tuff, upper cliff microstratigraphic unit), and a moderately welded tuff (Tiva Canyon Member of the Paintbrush Tuff, Caprock microstratigraphic unit). A massive fluvial sandstone (Berea Sandstone) was also investigated as a means of evaluating the experimental program and to provide a point of comparison for the tuff data. Because unsaturated flow is of prime interest to the Yucca Mountain Program, scoping studies aimed at investigating the up-scaling of hydraulic properties under various saturated conditions were performed to compliment these studies of intrinsic permeability. These studies focused on matrix sorptivity, a constitutive property quantifying the capillarity of a porous medium. 113 refs.

  1. Scale invariant alternatives to General Relativity II: Dilaton properties

    Karananas, Georgios K

    2016-01-01

    In the present paper we revisit gravitational theories which are invariant under TDiffs - transverse (volume preserving) diffeomorphisms and global scale transformations. It is known that these theories can be rewritten in an equivalent diffeomorphism-invariant form with an action including an integration constant (cosmological constant for the particular case of non scale-invariant unimodular gravity). The presence of this integration constant, in general, breaks explicitly scale invariance and induces a run-away potential for (otherwise massless) dilaton, associated with the determinant of the metric tensor. We show, however, that if the metric carries mass dimension $\\left[\\text{GeV}\\right]^{-2}$, the scale invariance of the system is preserved, unlike the situation in theories in which the metric has mass dimension different from $-2$. The dilaton remains massless and couples to other fields only through derivatives, without any conflict with observations. We observe that one can define a specific limit f...

  2. Scaling properties of image textures: A detrending fluctuation analysis approach

    Alvarez-Ramirez, Jose; Rodriguez, Eduardo; Cervantes, Ilse; Carlos Echeverria, Juan

    2006-03-01

    The aim of this paper is to explore the application of detrended fluctuation analysis (DFA) to study roughness features of images. Unidimensional sequences at different image orientations are extracted and their average scaling exponent is estimated. In this form, the existence of anisotropies can be detected when considerable variations in the scaling exponent at different image orientation are observed. Different images from grass to solar granulation are analyzed and the underlying physics of such results is briefly commented.

  3. The Determination Of Scaling Factor of Clay Properties

    Agus Sulaeman

    2015-05-01

    Full Text Available The observations and tests under small scale in 1-gravity condition is intended to obtain a comparative behavior of model and prototype of geotechnical case by imposing the scaling relations. Simulation to represent related structure, sub-soil and failure mechanism need to be prepared prior to do observations in this modelling. To obtain the new parameter for sub-soil simulation and inter-dependency with scaling relationship, the  ten samples with different water content of prototype clay soil were consolidated in the triaxial CU test.  After consolidation, each sample were given the arbitrarily initial mean stress po =1/3 (σ1+σ2+σ3 at the same time each corresponding void ratio were recorded. The data was plotted and numbered in the e Ln p’ axises to adopt critical state line concept. Further shear stage in triaxial CU test were done to record the stress and strain of each ten samples. Among those of ten stress strain curves there were 3 similar curves (1, 6 and 8 observed when the deviatoric stress was normalized with its po, this showed similar behavior among them. The further observation revealed that void ratio in the clay soil no. 8 (ep corresponded with void ratio of the sample no. 1 (em, stress ratio N and critical state line parameter l in the form of  em= ep+ l Ln N. To support the expression of  em= ep+ l Ln N,  The “pile loading test” case was prepared in small scale and full scale modeling, em   represented void ratio of clay in small scale and ep represented void ratio of clay at original project location. Load settlement curves were obtained from both “pile loading test” in small and full scale simulation and the result showed closely good agreement.

  4. Stroke detection based on the scaling properties of human EEG

    Hwa, Rudolph C.; Ferree, Thomas C.

    2004-07-01

    We propose a new method of detecting stroke by use of electroencephalogram (EEG) time series. When detrended fluctuation analysis is applied to the data, it is found that there exist two scaling regions for every channel. Thus with the geodesic sensor nets used there are as many as 128 paris of scaling exponents for each subject. We then determine a stroke index S that is based on the normalized variances of those scaling exponents. It is shown that S=1.3 distinctly separates the 28 normal and stroke subjects we have studied. We also show that the effect of stroke on EEG signals is global, in contrast to the local effect revealed by radiological studies such as MRI.

  5. Assessment of heterogeneous hydraulic properties in natural aquifers at the intermediate scale

    Zovi, Francesco

    2014-01-01

    One of the most relevant issues in groundwater hydrology is the assessment of heterogeneous hydraulic properties of natural aquifers at the intermediate scale. The intermediate scale includes, as a general definition, aquifers characterized by a ratio L/B, L being a linear measure of the horizontal extent, and B the average thickness, between one (local scale) and approximately one thousand (regional scale). In Italy groundwater represents almost eighty percent of drinkable water supply, ther...

  6. Returns-to-scale properties in DEA models: The fundmantal role of interior points

    Krivonozhko, Vladimir; Førsund, Finn R.

    2009-01-01

    Attempts can be found in the DEA literature to identify returns to scale at efficient interior points of the production possibility set on the basis of returns to scale at points of the corresponding reference sets. However, an opposite approach is put forward in this paper, advocating that returns-to-scale properties of efficient reference units should be found by identifying first returns to scale of an efficient interior unit that is a radial projection to the frontier of an inefficient un...

  7. Returms-to-scale Properties in DEA Models: The Fundamental Role of Interior Points

    Krivonozhko, Vladimir; Førsund, Finn R.

    2009-01-01

    Attempts can be found in the DEA literature to identify returns to scale at efficient interior points of the production possibility set on the basis of returns to scale at points of the corresponding reference sets. However, an opposite approach is put forward in this paper, advocating that returns-to-scale properties of efficient reference units should be found by identifying first returns to scale of an efficient interior unit that is a radial projection to the frontier of an inefficient un...

  8. Power Moments and Scaling Properties of Nuclear Emulsion Data

    Lee, S J

    1994-01-01

    Various features of the charge yield in heavy ion collisions are studied. Considered here are the nuclear emulsion data of $^{84}$Kr, $^{131}$Xe, $^{197}$Au, $^{238}$U in the energy range of 1 GeV/A. Mean charge yields and multiplicity distribution of these data indicate that the nuclear fragmentation at this energy is a multiprocess phenomena. Power moments of the charge distribution exhibit a scale invariance. While small nuclei (Kr and Xe) show a nuclear size dependence, large nuclei (Au and U) exhibit scale independence in their charge distribution.

  9. Psychometric Properties of a Social Abilities Evaluation Scale: C-scale

    María José Rabazo Méndez

    2004-11-01

    Full Text Available In this paper the psychometric data of a scale of evaluation of the social abilities (social expression and motor skills are presented. The scale was constructed to investigate social competence and antisocial conduct in adolescence. The process of the scale’s construction is explained; and the data on its internal consistency, its test-retest reliability, and its concurrent validity are presented. The scale was filled out by 325 teachers from different schools in the city of Badajoz (Spain; however, 20 scales were rejected because they were not properly completed. As well, the scale was analyzed, giving as a result 9 factors that explain 59.4% of the total variance. With the results obtained, the position of situational specificity with regard to social abilities is supported.

  10. Development and Psychometric Properties Gender Roles Attitude Scale

    Zeyneloglu, Simge; Terzioglu, Fusun

    2011-01-01

    This research was conducted for the purpose of developing a scaling tool to determine university students' attitudes towards gender roles. University students' attitudes should first be determined in order to change this traditional view to gender and to achieve a more egalitarian view. The research sample was comprised of one university's…

  11. Fundamental scaling properties of electro-mechanical switches

    We discuss the fundamental processes including electron conduction and adhesion of metallic contacts pertaining to the scaling of the performance metrics of nano-electro-mechanical switches. In particular, we show that under most circumstances, the switching energy is governed by the force that is needed in order to break the electrical contact when opening the switch. For an optimally designed parallel plate capacitor switch, the energy consumption does not depend on the actuation voltage. However, stray capacitances degrade the energy efficiency if a high operating voltage is chosen. The limit is of the order of 1 V for an aggressively scaled Si device, for which an overall switching energy of the order of 150 eV, a footprint area of 2500 nm2 and a switching time of 200 ps are predicted. The scaling analysis also stipulates that materials with a low free electron density and high effective mass should be used for the electrical contact, which is counter-intuitive, as such materials are known to be poor conductors on the macroscopic scale. (paper)

  12. Scale-invariant alternatives to general relativity. II. Dilaton properties

    Karananas, Georgios K.; Shaposhnikov, Mikhail

    2016-04-01

    In the present paper, we revisit gravitational theories which are invariant under TDiffs—transverse (volume-preserving) diffeomorphisms and global scale transformations. It is known that these theories can be rewritten in an equivalent diffeomorphism-invariant form with an action including an integration constant (cosmological constant for the particular case of non-scale-invariant unimodular gravity). The presence of this integration constant, in general, breaks explicitly scale invariance and induces a runaway potential for the (otherwise massless) dilaton, associated with the determinant of the metric tensor. We show, however, that if the metric carries mass dimension [GeV] -2 , the scale invariance of the system is preserved, unlike the situation in theories in which the metric has mass dimension different from -2 . The dilaton remains massless and couples to other fields only through derivatives, without any conflict with observations. We observe that one can define a specific limit for fields and their derivatives (in particular, the dilaton goes to zero, potentially related to the small distance domain of the theory) in which the only singular terms in the action correspond to the Higgs mass and the cosmological constant. We speculate that the self-consistency of the theory may require the regularity of the action, leading to the absence of the bare Higgs mass and cosmological constant, whereas their small finite values may be generated by nonperturbative effects.

  13. Psychometric properties of the Swedish version of the Resilience Scale.

    Lundman, Berit; Strandberg, Gunilla; Eisemann, Martin; Gustafson, Yngve; Brulin, Christine

    2007-06-01

    The aim of this study was to investigate resilience in relation to age and gender, and to elucidate the underlying structure of the Swedish version of the Resilience Scale (RS). The RS, originally created by Wagnild and Young is a 25 items scale of Lickert type with possible scores ranges from 25 to 175, the higher the score, the stronger resilience. A standardized procedure was used for translation. The analysis was based on 1719 participants, 1248 women and 471 men, from eight different samples, aged from 19 to 103 years. We found that the participants estimated their resilience as relatively high. There was a significant relationship between age and resilience, for every year RS score increased with 0.134 units. There was no relation between gender and resilience. From a factor analyses five factors emerged, equanimity, meaningfulness, perseverance, existential aloneness and self-reliance reflecting the five dimensions described by Wagnild and Young. We concluded that the resilience is related to age, the older, the stronger resilience. Five underlying dimensions was identified, which can be seen as reflection of the theoretical assumptions behind the RS scale. The RS scale seems applicable to a Swedish population. PMID:17559442

  14. Scaling properties of ionospheric, solar, and geomagnetic data

    Mošna, Zbyšek

    Magurele : Institute of Space Science, 2015. s. 51. [International Workshop and School on solar system plasma turbulence, intermittency and multifractals (STORM 2015). 06.09.2015-13.09.2015, Mamaia] Institutional support: RVO:68378289 Keywords : Scaling analysis * ionosphere * solar and geomagnetic activity Subject RIV: DG - Athmosphere Sciences, Meteorology http://www. space science.ro/conferences/storm2015/storm2015_book.pdf

  15. Properties of Brownian Image Models in Scale-Space

    Pedersen, Kim Steenstrup

    2003-01-01

    law that apparently governs natural images. Furthermore, the distribution of Brownian images mapped into jet space is Gaussian and an analytical expression can be derived for the covariance matrix of Brownian images in jet space. This matrix is also a good approximation of the covariance matrix...... Brownian images) will be discussed in relation to linear scale-space theory, and it will be shown empirically that the second order statistics of natural images mapped into jet space may, within some scale interval, be modeled by the Brownian image model. This is consistent with the 1/f 2 power spectrum...... of natural images in jet space. The consequence of these results is that the Brownian image model can be used as a least committed model of the covariance structure of the distribution of natural images....

  16. Psychometric properties of the Social Comparison Motives Scale.

    Tigges, Beth Baldwin

    2009-01-01

    This article describes the 19-item Social Comparison Motive Scale [SCMS], a measure of adolescents' motives for social comparison related to pregnancy. Dimensions and items were developed based on adolescent focus groups. The instrument was reviewed for content validity, pilot tested, and administered to 431 adolescents aged 14-18 years. Principal axis factor analysis with oblique rotation supported five dimensions. Convergent and discriminant validity were demonstrated by moderate correlations (r = .50) between the SCMS and the Iowa-Netherlands Comparison Orientation Measure and low correlations (r = .15) between the SCMS and the Rosenberg Self-Esteem Scale. Cronbach's alphas were .91 overall and .71 to .85 for the subscales. The SCMS demonstrated reliability and validity as a measure of adolescents' motives for comparing themselves with others about pregnancy. PMID:19902658

  17. Approximate scaling properties of RNA free energy landscapes

    Baskaran, S.; Stadler, P. F.; Schuster, P.

    1996-01-01

    RNA free energy landscapes are analysed by means of "time-series" that are obtained from random walks restricted to excursion sets. The power spectra, the scaling of the jump size distribution, and the scaling of the curve length measured with different yard stick lengths are used to describe the structure of these "time series". Although they are stationary by construction, we find that their local behavior is consistent with both AR(1) and self-affine processes. Random walks confined to excursion sets (i.e., with the restriction that the fitness value exceeds a certain threshold at each step) exhibit essentially the same statistics as free random walks. We find that an AR(1) time series is in general approximately self-affine on timescales up to approximately the correlation length. We present an empirical relation between the correlation parameter rho of the AR(1) model and the exponents characterizing self-affinity.

  18. Density scaling as a property of strongly correlating viscous liquids

    Schrøder, Thomas; Pedersen, Ulf Rørbæk; Bailey, Nicholas; Toxværd, Søren; Dyre, J.C.

    2008-01-01

    Results from molecular dynamics simulations of two viscous molecular model liquids -- the Lewis-Wahnstrom model of ortho-terphenyl and an asymmetric dumbbell model -- are reported. We demonstrate that the liquids have a ``hidden'' approximate scale invariance: Equilibrium potential energy fluctuations are accurately described by inverse power law (IPL) potentials, the radial distribution functions are accurately reproduced by the IPL's, and the radial distribution functions obey the IPL predi...

  19. LCAO approximation for scaling properties of the Menger sponge fractal.

    Sakoda, Kazuaki

    2006-11-13

    The electromagnetic eigenmodes of a three-dimensional fractal called the Menger sponge were analyzed by the LCAO (linear combination of atomic orbitals) approximation and a first-principle calculation based on the FDTD (finite-difference time-domain) method. Due to the localized nature of the eigenmodes, the LCAO approximation gives a good guiding principle to find scaled eigenfunctions and to observe the approximate self-similarity in the spectrum of the localized eigenmodes. PMID:19529555

  20. Characteristic Length Scale of Electric Transport Properties of Genomes

    Shih, C T

    2005-01-01

    A tight-binding model together with a novel statistical method are used to investigate the relation between the sequence-dependent electric transport properties and the sequences of protein-coding regions of complete genomes. A correlation parameter $\\Omega$ is defined to analyze the relation. For some particular propagation length $w_{max}$, the transport behaviors of the coding and non-coding sequences are very different and the correlation reaches its maximal value $\\Omega_{max}$. $w_{max}$ and \\omax are characteristic values for each species. The possible reason of the difference between the features of transport properties in the coding and non-coding regions is the mechanism of DNA damage repair processes together with the natural selection.

  1. Scale-by-scale analysis of probability distributions for global MODIS-AQUA cloud properties: how the large scale signature of turbulence may impact statistical analyses of clouds

    M. de la Torre Juárez

    2011-03-01

    Full Text Available Means, standard deviations, homogeneity parameters used in models based on their ratio, and the probability distribution functions (PDFs of cloud properties from the MODerate resolution Infrared Spectrometer (MODIS are estimated globally as function of averaging scale varying from 5 to 500 km. The properties – cloud fraction, droplet effective radius, and liquid water path – all matter for cloud-climate uncertainty quantification and reduction efforts. Global means and standard deviations are confirmed to change with scale. For the range of scales considered, global means vary only within 3% for cloud fraction, 7% for liquid water path, and 0.2% for cloud particle effective radius. These scale dependences contribute to the uncertainties in their global budgets. Scale dependence for standard deviations and generalized flatness are compared to predictions for turbulent systems. Analytical expressions are identified that fit best to each observed PDF. While the best analytical PDF fit to each variable differs, all PDFs are well described by log-normal PDFs when the mean is normalized by the standard deviation inside each averaging domain. Importantly, log-normal distributions yield significantly better fits to the observations than gaussians at all scales. This suggests a possible approach for both sub-grid and unified stochastic modeling of these variables at all scales. The results also highlight the need to establish an adequate spatial resolution for two-stream radiative studies of cloud-climate interactions.

  2. Properties of large-scale methane/hydrogen jet fires

    A future economy based on reduction of carbon-based fuels for power generation and transportation may consider hydrogen as possible energy carrier Extensive and widespread use of hydrogen might require a pipeline network. The alternatives might be the use of the existing natural gas network or to design a dedicated network. Whatever the solution, mixing hydrogen with natural gas will modify the consequences of accidents, substantially The French National Research Agency (ANR) funded project called HYDROMEL focuses on these critical questions Within this project large-scale jet fires have been studied experimentally and numerically The main characteristics of these flames including visible length, radiation fluxes and blowout have been assessed. (authors)

  3. Dimensional scaling effects on transport properties of ultrathin body p-i-n diodes

    Rajasekharan, B.; van der Salm, C.; Hueting, R.J.E.; Hoang, Van T.; Schmitz, J.

    2008-01-01

    Device scaling has been a subject of research for both optoelectronics and electronics. In order to investigate the electronic properties of scaled devices we studied lateral p-i-n structures using thin silicon on insulator (SOI) or poly-Si layers of varying dimension. With the help of these structures we try to explain the size dependencies on electronic transport properties. Further, we also propose a new device concept called charge plasma diode.

  4. The effects of scales, flows and filters on property rights and collective action in watershed management:

    Swallow, Brent M.; Garrity, Dennis P.; van Noordwijk, Meine

    2001-01-01

    Research and policy on property rights, collective action and watershed management requires good understanding of ecological and socio-political processes at different social-spatial scales. On-farm soil erosion is a plot or farm-level problem that can be mitigated through more secure property rights for individual farmers, while the sedimentation of streams and deterioration of water quality are larger-scale problems that may require more effective collective action and / or more secure prop...

  5. Bibliometric statistical properties of the 100 largest European universities: prevalent scaling rules in the science system

    van Raan, Anthony F. J.

    2007-01-01

    For the 100 largest European universities we studied the statistical properties of bibliometric indicators related to research performance, field citation density and journal impact. We find a size-dependent cumulative advantage for the impact of universities in terms of total number of citations. In previous work a similar scaling rule was found at the level of research groups. Therefore we conjecture that this scaling rule is a prevalent property of the science system. We observe that lower...

  6. The attitudes toward transgendered individuals scale: psychometric properties.

    Walch, Susan E; Ngamake, Sakkaphat T; Francisco, Jacquelyn; Stitt, Rashunda L; Shingler, Kimberly A

    2012-10-01

    Gay, lesbian, bisexual, and transgendered individuals are sexual and gender minorities subject to stigma in a heteronormative culture with binary gender role norms. Although much research has examined sexual stigma in the form of homophobia, or negative attitudes and reactions to homosexuals and homosexuality, little is known about the stigma experienced by transgendered individuals. Transgendered people are those whose gender identity (sense of oneself as a man or a woman) or gender expression (expression of oneself as a man or a woman in behavior, manner, and/or dress) differ from conventional expectations for their physical sex. Although a scale exists to measure transphobia or negative attitudes and reactions to transgendered individuals, it includes items tapping into overt behavioral expression of this stigma, or gender-bashing, and fails to identify or define transgendered persons as the attitudinal target of the items. A new scale was developed and evaluated in an effort to assess transgender-related stigma, separately from discrimination and violence, among members of the general population. Using two separate samples of college students ranging in age from 18-64 years, exploratory (N = 134) and confirmatory factor analyses (N = 237) were performed. The resulting 20-item, self-report measure demonstrated a single-factor structure, high internal consistency reliability, and evidence of convergent and discriminant construct validity. PMID:22810996

  7. Soil properties and preferential solute transport at the field scale

    Koestel, J K; Minh, Luong Nhat; Nørgaard, Trine;

    An important fraction of water flow and solute transport through soil takes place through preferential flow paths. Although this had been already observed in the nineteenth century, it had been forgotten by the scientific community until it was rediscovered during the 1970s. The awareness of the...... relevance of preferential flow was broadly re-established in the community by the early 1990s. However, since then, the notion remains widespread among soil scientists that the occurrence and strength of preferential flow cannot be predicted from measurable proxy variables such as soil properties or land...

  8. Rating scale analysis and psychometric properties of the Caregiver Self-Efficacy Scale for Transfers

    Cipriani, D.J.; Hensen, Fenna; McPeck, D.L.; Kubec, G.L.; Thomas, J.J.

    2012-01-01

    Parents and caregivers faced with the challenges of transferring children with disability are at risk of musculoskeletal injuries and/or emotional stress. The Caregiver Self-Efficacy Scale for Transfers (CSEST) is a 14-item questionnaire that measures self-efficacy for transferring under common cond

  9. The Severe Sexual Sadism Scale: Cross-Validation and Scale Properties

    Mokros, Andreas; Schilling, Frank; Eher, Reinhard; Nitschke, Joachim

    2012-01-01

    The Severe Sexual Sadism Scale (SSSS) is a screening device for the file-based assessment of forensically relevant sexual sadism. The SSSS consists of 11 dichotomous (yes/no) items that code behavioral indicators of severe sexual sadism within sexual offenses. Based on an Austrian sample of 105 sexual offenders, the present study replicated the…

  10. Psychometric properties of the Perceptual Aberration Scale and the Magical Ideation Scale in Spanish college students

    Eduardo Fonseca-Pedrero

    2009-01-01

    Magical Ideation Scale seem to be useful self-reports for the identification of subjects with a higher risk of developing schizophrenia-spectrum disorders. Future research should replicate these findings in samples of other nationalities, determine the contribution of each dimension in the transition to psychosis, as well as apply them in clinical practice along with endophenotypes.

  11. Psychometric properties of the satisfaction with food-related Life Scale

    Schnettler, Berta; Miranda, Horacio; Sepúlveda, José;

    2013-01-01

    Objective: To evaluate the psychometric properties of the Satisfaction with Food-related Life (SWFL) scale and its relation to the Satisfaction with Life Scale (SWLS) in southern Chile. Methods: A survey was applied to a sample of 316 persons in the principal cities of southern Chile distributed...

  12. Symmetric scaling properties in global surface air temperature anomalies

    Varotsos, Costas A.; Efstathiou, Maria N.

    2015-08-01

    We have recently suggested "long-term memory" or internal long-range correlation within the time-series of land-surface air temperature (LSAT) anomalies in both hemispheres. For example, an increasing trend in the LSAT anomalies is followed by another one at a different time in a power-law fashion. However, our previous research was mainly focused on the overall long-term persistence, while in the present study, the upward and downward scaling dynamics of the LSAT anomalies are analysed, separately. Our results show that no significant fluctuation differences were found between the increments and decrements in LSAT anomalies, over the whole Earth and over each hemisphere, individually. On the contrary, the combination of land-surface air and sea-surface water temperature anomalies seemed to cause a departure from symmetry and the increments in the land and sea surface temperature anomalies appear to be more persistent than the decrements.

  13. Scaling properties of Wilson loops pierced by P-vortices

    Dunn, Patrick; Greensite, Jeffrey Paul

    2012-01-01

    P-vortices, in an SU(N) lattice gauge theory, are excitations on the center-projected Z(N) lattice. We study the ratio of expectation values of SU(2) Wilson loops, on the unprojected lattice, linked to a single P-vortex, to that of Wilson loops which are not linked to any P-vortices. When these...... ratios are plotted versus loop area in physical units, for a range of lattice couplings, it is found that the points fall approximately on a single curve, consistent with scaling. We also find that the ratios are rather insensitive to the point where the minimal area of the loop is pierced by the P-vortex....

  14. Properties of large-scale TIDs observed in Central China

    TANG; Qiulin(汤秋林); WAN; Weixing(万卫星); NING; Baiqi(宁百齐); YUAN; Hong(袁洪)

    2002-01-01

    This paper investigates the large scale travelling ionospheric disturbances (LSTIDs) using the observation data of an HF Doppler array located in Central China. The data observed in a high solar activity year (year 1989) are analyzed to obtain the main propagation parameters of LSTIDs such as period, horizontal phase velocity and propagating direction. Results are outlined as follows: Most of the LSTIDs propagate southward; others tend to propagate northward, mostly in summer; dispersion of most LSTIDs is matched with that of Lamb pseudomode, while others have the dispersion of long period gravity wave mode. The horizontal phase velocities of these two modes are about 220 and 450 m/s respectively. The analysis shows that LSTIDs are strongly pertinent to solar activity and space magnetic storms; thus the results presented here are significant for the research of ionospheric weather in mid-low latitude region.

  15. Scaling properties of cavity-enhanced atom cooling

    Horak, P; Horak, Peter; Ritsch, Helmut

    2001-01-01

    We extend an earlier semiclassical model to describe the dissipative motion of N atoms coupled to M modes inside a coherently driven high-finesse cavity. The description includes momentum diffusion via spontaneous emission and cavity decay. Simple analytical formulas for the steady-state temperature and the cooling time for a single atom are derived and show surprisingly good agreement with direct stochastic simulations of the semiclassical equations for N atoms with properly scaled parameters. A thorough comparison with standard free-space Doppler cooling is performed and yields a lower temperature and a cooling time enhancement by a factor of M times the square of the ratio of the atom-field coupling constant to the cavity decay rate. Finally it is shown that laser cooling with negligible spontaneous emission should indeed be possible, especially for relatively light particles in a strongly coupled field configuration.

  16. Ternary eutectic dendrites: Pattern formation and scaling properties

    Rátkai, László; Szállás, Attila; Pusztai, Tamás [Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, P.O. Box 49, H-1525 Budapest (Hungary); Mohri, Tetsuo [Center for Computational Materials Science, Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Gránásy, László, E-mail: granasy.laszlo@wigner.mta.hu [Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, P.O. Box 49, H-1525 Budapest (Hungary); Brunel University, Uxbridge, Middlesex UB8 3PH (United Kingdom)

    2015-04-21

    Extending previous work [Pusztai et al., Phys. Rev. E 87, 032401 (2013)], we have studied the formation of eutectic dendrites in a model ternary system within the framework of the phase-field theory. We have mapped out the domain in which two-phase dendritic structures grow. With increasing pulling velocity, the following sequence of growth morphologies is observed: flat front lamellae → eutectic colonies → eutectic dendrites → dendrites with target pattern → partitionless dendrites → partitionless flat front. We confirm that the two-phase and one-phase dendrites have similar forms and display a similar scaling of the dendrite tip radius with the interface free energy. It is also found that the possible eutectic patterns include the target pattern, and single- and multiarm spirals, of which the thermal fluctuations choose. The most probable number of spiral arms increases with increasing tip radius and with decreasing kinetic anisotropy. Our numerical simulations confirm that in agreement with the assumptions of a recent analysis of two-phase dendrites [Akamatsu et al., Phys. Rev. Lett. 112, 105502 (2014)], the Jackson-Hunt scaling of the eutectic wavelength with pulling velocity is obeyed in the parameter domain explored, and that the natural eutectic wavelength is proportional to the tip radius of the two-phase dendrites. Finally, we find that it is very difficult/virtually impossible to form spiraling two-phase dendrites without anisotropy, an observation that seems to contradict the expectations of Akamatsu et al. Yet, it cannot be excluded that in isotropic systems, two-phase dendrites are rare events difficult to observe in simulations.

  17. Ternary eutectic dendrites: Pattern formation and scaling properties

    Extending previous work [Pusztai et al., Phys. Rev. E 87, 032401 (2013)], we have studied the formation of eutectic dendrites in a model ternary system within the framework of the phase-field theory. We have mapped out the domain in which two-phase dendritic structures grow. With increasing pulling velocity, the following sequence of growth morphologies is observed: flat front lamellae → eutectic colonies → eutectic dendrites → dendrites with target pattern → partitionless dendrites → partitionless flat front. We confirm that the two-phase and one-phase dendrites have similar forms and display a similar scaling of the dendrite tip radius with the interface free energy. It is also found that the possible eutectic patterns include the target pattern, and single- and multiarm spirals, of which the thermal fluctuations choose. The most probable number of spiral arms increases with increasing tip radius and with decreasing kinetic anisotropy. Our numerical simulations confirm that in agreement with the assumptions of a recent analysis of two-phase dendrites [Akamatsu et al., Phys. Rev. Lett. 112, 105502 (2014)], the Jackson-Hunt scaling of the eutectic wavelength with pulling velocity is obeyed in the parameter domain explored, and that the natural eutectic wavelength is proportional to the tip radius of the two-phase dendrites. Finally, we find that it is very difficult/virtually impossible to form spiraling two-phase dendrites without anisotropy, an observation that seems to contradict the expectations of Akamatsu et al. Yet, it cannot be excluded that in isotropic systems, two-phase dendrites are rare events difficult to observe in simulations

  18. Psychometric Properties of the Depression Anxiety and Stress Scale-21 in Older Primary Care Patients

    Gloster, Andrew T.; Rhoades, Howard M.; Novy, Diane; Klotsche, Jens; Senior, Ashley; Kunik, Mark; Wilson, Nancy; Stanley, Melinda A.

    2008-01-01

    The Depression Anxiety Stress Scale (DASS) was designed to efficiently measure the core symptoms of anxiety and depression and has demonstrated positive psychometric properties in adult samples of anxiety and depression patients and student samples. Despite these findings, the psychometric properties of the DASS remain untested in older adults, for whom the identification of efficient measures of these constructs is especially important.

  19. Silver nanoparticles: Large scale solvothermal synthesis and optical properties

    Silver nanoparticles have been successfully synthesized by a simple and modified solvothermal method at large scale using ethanol as the refluxing solvent and NaBH4 as reducing agent. The nanopowder was investigated by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS), UV-visible and BET surface area studies. XRD studies reveal the monophasic nature of these highly crystalline silver nanoparticles. Transmission electron microscopic studies show the monodisperse and highly uniform nanoparticles of silver of the particle size of 5 nm, however, the size is found to be 7 nm using dynamic light scattering which is in good agreement with the TEM and X-ray line broadening studies. The surface area was found to be 34.5 m2/g. UV-visible studies show the absorption band at ∼425 nm due to surface plasmon resonance. The percentage yield of silver nanoparticles was found to be as high as 98.5%.

  20. Soil properties and preferential solute transport at the field scale

    Koestel, J. K.; Luong, N. M.; Nørgaard, T.; Vendelboe, A. L.; Moldrup, P.; Jarvis, N. J.; Lamandé, M.; Iversen, B. V.; Wollesen de Jonge, L.

    2012-04-01

    An important fraction of water flow and solute transport through soil takes place through preferential flow paths. Although this had been already observed in the nineteenth century, it had been forgotten by the scientific community until it was rediscovered during the 1970s. The awareness of the relevance of preferential flow was broadly re-established in the community by the early 1990s. However, since then, the notion remains widespread among soil scientists that the occurrence and strength of preferential flow cannot be predicted from measurable proxy variables such as soil properties or land management practices (e.g. Beven, K., 1991, Modeling preferential flow - an uncertain future, Preferential Flow, 1-11). In our study, we present evidence that disproves this notion. We evaluated breakthrough curve experiments under a constant irrigation rate of 1 cm/h conducted on 65 soil columns (20 cm diameter and 20 height) which had been sampled from an approximately 1 ha large loamy field-site in Silstrup, Denmark. We show that the holdback factor, which is an indicator for the strength of preferential transport, is strongly correlated to the bulk density, which in turn is correlated to the organic matter content. By applying multiple linear regression in a bootstrapping framework, we could estimate the holdback factor from the bulk density and the very fine sand fraction with a coefficient of determination of 0.65. Our results raise hopes that it is indeed possible to establish pedotransfer functions for soil susceptibility to preferential flow and transport.

  1. Electronic transport properties of copper and gold at atomic scale

    Mohammadzadeh, Saeideh

    2010-11-23

    The factors governing electronic transport properties of copper and gold atomic-size contacts are theoretically examined in the present work. A two-terminal conductor using crystalline electrodes is adopted. The non-equilibrium Green's function combined with the density functional tight-binding method is employed via gDFTB simulation tool to calculate the transport at both equilibrium and non-equilibrium conditions. The crystalline orientation, length, and arrangement of electrodes have very weak influence on the electronic characteristics of the considered atomic wires. The wire width is found to be the most effective geometric aspect determining the number of conduction channels. The obtained conductance oscillation and linear current-voltage curves are interpreted. To analyze the conduction mechanism in detail, the transmission channels and their decomposition to the atomic orbitals are calculated in copper and gold single point contacts. The presented results offer a possible explanation for the relation between conduction and geometric structure. Furthermore, the results are in good agreement with available experimental and theoretical studies. (orig.)

  2. Scaled down physical properties of semiconductor nanowires for nanoelectronics scaling up

    Carapezzi, Stefania

    2014-01-01

    Semiconductor nanowires (NWs) are one- or quasi one-dimensional systems whose physical properties are unique as compared to bulk materials because of their nanoscaled sizes. They bring together quantum world and semiconductor devices. NWs-based technologies may achieve an impact comparable to that of current microelectronic devices if new challenges will be faced. This thesis primarily focuses on two different, cutting-edge aspects of research over semiconductor NW arrays as pivotal component...

  3. Development and examination of the psychometric properties of the Learning Experience Scale in nursing.

    Takase, Miyuki; Imai, Takiko; Uemura, Chizuru

    2016-06-01

    This paper examines the psychometric properties of the Learning Experience Scale. A survey method was used to collect data from a total of 502 nurses. Data were analyzed by factor analysis and the known-groups technique to examine the construct validity of the scale. In addition, internal consistency was evaluated by Cronbach's alpha, and stability was examined by test-retest correlation. Factor analysis showed that the Learning Experience Scale consisted of five factors: learning from practice, others, training, feedback, and reflection. The scale also had the power to discriminate between nurses with high and low levels of nursing competence. The internal consistency and the stability of the scale were also acceptable. The Learning Experience Scale is a valid and reliable instrument, and helps organizations to effectively design learning interventions for nurses. PMID:26373632

  4. Scaling properties of evolutionary paths in a biophysical model of protein adaptation

    Manhart, Michael; Morozov, Alexandre V.

    2015-07-01

    The enormous size and complexity of genotypic sequence space frequently requires consideration of coarse-grained sequences in empirical models. We develop scaling relations to quantify the effect of this coarse-graining on properties of fitness landscapes and evolutionary paths. We first consider evolution on a simple Mount Fuji fitness landscape, focusing on how the length and predictability of evolutionary paths scale with the coarse-grained sequence length and alphabet. We obtain simple scaling relations for both the weak- and strong-selection limits, with a non-trivial crossover regime at intermediate selection strengths. We apply these results to evolution on a biophysical fitness landscape that describes how proteins evolve new binding interactions while maintaining their folding stability. We combine the scaling relations with numerical calculations for coarse-grained protein sequences to obtain quantitative properties of the model for realistic binding interfaces and a full amino acid alphabet.

  5. Psychometric properties of a single-item scale to assess sleep quality among individuals with fibromyalgia

    Sadosky Alesia B; McDermott Anne M; Bushmakin Andrew G; Cappelleri Joseph C; Petrie Charles D; Martin Susan

    2009-01-01

    Abstract Background Sleep disturbances are a common and bothersome symptom of fibromyalgia (FM). This study reports psychometric properties of a single-item scale to assess sleep quality among individuals with FM. Methods Analyses were based on data from two randomized, double-blind, placebo-controlled trials of pregabalin (studies 1056 and 1077). In a daily diary, patients reported the quality of their sleep on a numeric rating scale ranging from 0 ("best possible sleep") to 10 ("worst possi...

  6. Psychometric properties of a short form of the Affective Lability Scale (ALS-18)

    Look, Amy E.; Flory, Janine D.; Harvey, Philip D.; Siever, Larry J.

    2010-01-01

    Psychometric properties of a short form of the Affective Lability Scale (ALS) that was developed in a nonclinical sample (i.e., undergraduate students) were examined in a sample of people diagnosed with Cluster B DSM-IV Axis II personality disorders (n=236), other personality disorders (n=180), and healthy comparison participants (n=164). The total score of the ALS-18 score correlated strongly with the original 54-item scale (r = .97) and aspects of convergent and discriminant validity of the...

  7. Testing properties of potato starch from different scales of isolations - A ringtest

    Wischmann, Bente; Ahmt, T.; Bandsholm, O.;

    2007-01-01

    Five different procedures were used to isolate potato starch from the same batch at three different scales in order to analyse what influence scaling up of the starch process had on the starch physical/chemical properties. Common to the five isolation processes was the steps of washing and...... maceration of potato tubers followed by separation of starch and cell debris by sieving, filtration or sedimentation. The properties of the processed starch were analysed both in water-based systems of 10 mM NaCl as well as in a milk based food model, dutch vla. Analysis of chemical and physical properties...... by a rapid visco analyser (RVA) and freeze/thaw stability and retrogradation characteristics analysed by pulse-NMR. Various theological flow properties were included in the analysis of the starch samples in the food model. Only the sample of starch isolated in distilled water showed significant...

  8. Depth dependence of seismic source scaling properties beneath Vrancea, Romania region

    Previous research focused on seismicity, tomography and seismic source scaling in the Vrancea region revealed significant plate subducting irregularity which was assumed to be in connection with multiple parameter and multi-scale fields, reflecting differences in the physical, geochemical and tectonic processes at different scale lengths. A substantial new amount of high-quality earthquake data have been recently gained through the progress of seismic networks on the Romanian territory within the cooperation programme with the University of Karlsruhe (Germany): Collaborative Research Centre 461 programme (Bonjer et al., 2000) and the tomography experiment CALIXTO'99 (Wenzel et al., 1999). The main purpose of the present study is to study the depth dependence of the seismic source scaling in the Vrancea subducting slab on the basis of these new data. Spectral ratios and empirical Green's function deconvolution methods are applied for a set of 130 earthquakes with magnitudes 2.9 ≤ Mw ≤ 6.0, occurred between 1996 and 2005. The two relative methods are employed to pairs of collocated events and similar focal mechanism, in order to inspect the scaling properties over the seismic active depth domain (60-220 km). The results are discussed in connection with previous studies based on fractal statistics analysis. The clustering properties of time, space and size distributions as well as the scaling variations in the subducting lithosphere are ascribed to differences in specific source mechanisms or/and structural inhomogeneity properties with hierarchical distribution. (authors)

  9. Measurement properties of the Minimal Insomnia Symptom Scale (MISS) in an elderly population in Sweden.

    Fagerström Cecilia; Hagell Peter; Hellström Amanda; Willman Ania

    2010-01-01

    Abstract Background Insomnia is common among elderly people and associated with poor health. The Minimal Insomnia Symptom Scale (MISS) is a three item screening instrument that has been found to be psychometrically sound and capable of identifying insomnia in the general population (20-64 years). However, its measurement properties have not been studied in an elderly population. Our aim was to test the measurement properties of the MISS among people aged 65 + in Sweden, by replicating the ori...

  10. Multi-scale modeling in heterogeneous material properties : An application to porous piezoelectric material

    Asai, Mitsuteru

    2012-01-01

    Many engineering problems involve different scale in space or time. The main interest for engineering designer is to find an optimum macroscopic response of structure, although the macroscopic response is strongly dependent on the microscopic material properties. The material itself has an individual microstructure, and the optimum material is fabricated by controlling the microstructure. Usually, the macroscopic material properties are measured by the experimental material tests. The asympto...

  11. Physical and functional properties of chromatography media : a down-scale study

    Hansson, Emma

    2013-01-01

    During down scale of column chromatography a phenomenon called wall effect appears.This supports the gel bed and gives it better flow properties. Using three different media infive different sized columns this effect was investigated regarding the physical andfunctional properties of the media. The conclusion of this study is that the effect appears incolumns below 26 mm in diameter and that the impact of the wall effect is larger the morerigid the used media is.

  12. Length Scales and Turbulent Properties of Magnetic Fields in Simulated Galaxy Clusters

    Egan, Hilary; Hallman, Eric; Burns, Jack; Xu, Hao; Collins, David; Li, Hui; Norman, Michael L

    2016-01-01

    Additional physics beyond standard hydrodynamics is needed to fully model the intracluster medium (ICM); however, as we move to more sophisticated models, it is important to consider the role of magnetic fields and the way the fluid approximation breaks down. This paper represents a first step towards developing a self-consistent model of the ICM by characterizing the statistical properties of magnetic fields in cosmological simulations of galaxy clusters. We find that plasma conditions are largely homogeneous across a range of cluster masses and relaxation states. We also find that the magnetic field length scales are resolution dependent and not based on any particular physical process. Energy transfer mechanisms and scales are also identified, and imply the existence of small scale dynamo action. The scales of the small scale dynamo are resolution limited and driven by numerical resistivity and viscosity.

  13. Scaling of material properties for Yucca Mountain: literature review and numerical experiments on saturated hydraulic conductivity

    McKenna, S.A.; Rautman, C.A.

    1996-08-01

    A review of pertinent literature reveals techniques which may be practical for upscaling saturated hydraulic conductivity at Yucca Mountain: geometric mean, spatial averaging, inverse numerical modeling, renormalization, and a perturbation technique. Isotropic realizations of log hydraulic conductivity exhibiting various spatial correlation lengths are scaled from the point values to five discrete scales through these techniques. For the variances in log{sub 10} saturated hydraulic conductivity examined here, geometric mean, numerical inverse and renormalization adequately reproduce point scale fluxes across the modeled domains. Fastest particle velocities and dispersion measured on the point scale are not reproduced by the upscaled fields. Additional numerical experiments examine the utility of power law averaging on a geostatistical realization of a cross-section similar to the cross-sections that will be used in the 1995 groundwater travel time calculations. A literature review on scaling techniques for thermal and mechanical properties is included. 153 refs., 29 figs., 6 tabs.

  14. Scaling of material properties for Yucca Mountain: literature review and numerical experiments on saturated hydraulic conductivity

    A review of pertinent literature reveals techniques which may be practical for upscaling saturated hydraulic conductivity at Yucca Mountain: geometric mean, spatial averaging, inverse numerical modeling, renormalization, and a perturbation technique. Isotropic realizations of log hydraulic conductivity exhibiting various spatial correlation lengths are scaled from the point values to five discrete scales through these techniques. For the variances in log10 saturated hydraulic conductivity examined here, geometric mean, numerical inverse and renormalization adequately reproduce point scale fluxes across the modeled domains. Fastest particle velocities and dispersion measured on the point scale are not reproduced by the upscaled fields. Additional numerical experiments examine the utility of power law averaging on a geostatistical realization of a cross-section similar to the cross-sections that will be used in the 1995 groundwater travel time calculations. A literature review on scaling techniques for thermal and mechanical properties is included. 153 refs., 29 figs., 6 tabs

  15. Development and Psychometric Properties of the Emotional Intelligence Admission Essay Scale

    Sharon A. Gutman

    2016-07-01

    Full Text Available The purpose was to describe the development and psychometric properties of the Emotional Intelligence Admission Essay scale. The authors developed an admission essay question and rating scale designed to provide information about applicants’ emotional intelligence (EI. Content validity, convergent validity, interrater reliability, and internal consistency were established. The scale was also examined to determine if it could discriminate between students with and without professional behavior problems in the academic and fieldwork settings. Content validity was found to be high by a panel of three experts in EI (content validity index = 1.0. Convergent validity with the Assessing Emotions Scale was moderate (r = .46, p < .02. Interrater reliability between two trained faculty raters was high (ICC = .91, p < .000. Internal consistency of the scale was high with a Cronbach’s alpha of .95. This version of the scale was not able to discriminate between students with and without professional behavior problems. The moderate to strong psychometric properties suggest that the EI Admission Essay Scale has the ability to provide information about applicants’ EI. The wording of the essay question must be modified to better instruct applicants to address interpersonal conflict.

  16. Multi-scales modeling of reactive transport mechanisms. Impact on petrophysical properties during CO2 storage

    The geo-sequestration of carbon dioxide (CO2) is an attractive option to reduce the emission of greenhouse gases. Within carbonate reservoirs, acidification of brine in place can occur during CO2 injection. This acidification leads to mineral dissolution which can modify the transport properties of a solute in porous media. The aim of this study is to quantify the impact of reactive transport on a solute distribution and on the structural modification induced by the reaction from the pore to the reservoir scale. This study is focused on reactive transport problem in the case of single phase flow in the limit of long time. To do so, we used a multi-scale up-scaling method that takes into account (i) the local scale, where flow, reaction and transport are known; (ii) the pore scale, where the reactive transport is addressed by using averaged formulation of the local equations; (iii) the Darcy scale (also called core scale), where the structure of the rock is taken into account by using a three-dimensions network of pore-bodies connected by pore-throats; and (iv) the reservoir scale, where physical phenomenon, within each cell of the reservoir model, are taken into account by introducing macroscopic coefficients deduced from the study of these phenomenon at the Darcy scale, such as the permeability, the apparent reaction rate, the solute apparent velocity and dispersion. (author)

  17. Investigating the Measurement Properties of the Social Responsiveness Scale in Preschool Children with Autism Spectrum Disorders

    Duku, Eric; Vaillancourt, Tracy; Szatmari, Peter; Georgiades, Stelios; Zwaigenbaum, Lonnie; Smith, Isabel M.; Bryson, Susan; Fombonne, Eric; Mirenda, Pat; Roberts, Wendy; Volden, Joanne; Waddell, Charlotte; Thompson, Ann; Bennett, Teresa

    2013-01-01

    The purpose of this study was to examine the measurement properties of the Social Responsiveness Scale in an accelerated longitudinal sample of 4-year-old preschool children with the complementary approaches of categorical confirmatory factor analysis and Rasch analysis. Measurement models based on the literature and other hypothesized measurement…

  18. Psychometric Properties of the Chinese Version of the Social Responsiveness Scale

    Gau, Susan Shur-Fen; Liu, Li-Ting; Wu, Yu-Yu; Chiu, Yen-Nan; Tsai, Wen-Che

    2013-01-01

    This study evaluated the psychometric properties of the Chinese version of the Social Responsiveness Scale (Chinese SRS). We assessed 1419 grade 1 to grade 8 students from northern Taiwan and 401 clinic-based participants (aged 3-20, male 90.3%). All clinic-based participants were clinically diagnosed with autism spectrum disorders (ASDs),…

  19. Psychometric Properties of a Korean Translation of the "Scales of Independent Behavior--Revised"

    Cho, Su-Je; Paik, Eunhee; Lee, Byoung-In; Yi, Joonsuk

    2010-01-01

    This study explores the psychometric properties of data drawn from the Korean translation of the full "Scales of Independent Behavior--Revised" (SIB-R). In addition, semantic, content, conceptual, and technical equivalence are examined. The participants include 2,763 typically developing children and 406 children with intellectual disabilities…

  20. Assessing Psychometric Properties of the Sex-Role Egalitarianism Scale (SRES) with African Americans.

    McGhee, Melissa R.; Johnson, NeSonya; Liverpool, Joan

    2001-01-01

    Examined the psychometric properties of the Sex-Role Egalitarianism Scale in a group of African American college students, comparing scores from this sample to scores of a predominantly white norming base. While there were no significant differences between the norming sample and study sample, significant differences were found between African…

  1. Psychometric Properties of the MMPI-2-RF Somatic Complaints (RC1) Scale

    Thomas, Michael L.; Locke, Dona E. C.

    2010-01-01

    The MMPI-2 Restructured Form (MMPI-2-RF; Tellegen & Ben-Porath, 2008) was designed to be psychometrically superior to its MMPI-2 counterpart. However, the test has yet to be extensively evaluated in diverse clinical settings. The purpose of this study was to examine the psychometric properties of the MMPI-2-RF Somatic Complaints (RC1) scale in a…

  2. Measuring Grief Following Miscarriage: Psychometric Properties of the Chinese Version of the Perinatal Grief Scale

    Lai, Beatrice P. Y.; Chung, Tony K. H.; Lee, Dominic T. S.; Kong, Grace W. S.; Lok, Ingrid H.

    2013-01-01

    Grief following miscarriage is a complex psychological response. This study was conducted to examine the psychometric properties of the Chinese version of the Perinatal Grief Scale (PGS). A total of 280 Chinese women completed the PGS immediately following a diagnosis of miscarriage (baseline) and were reassessed at 12 months follow-up. The factor…

  3. Nonlinear option pricing models for illiquid markets: scaling properties and explicit solutions

    Bordag, Ljudmila A.; Ruediger Frey

    2007-01-01

    Several models for the pricing of derivative securities in illiquid markets are discussed. A typical type of nonlinear partial differential equations arising from these investigation is studied. The scaling properties of these equations are discussed. Explicit solutions for one of the models are obtained and studied.

  4. The axiomatic definition of a linguistic scale fuzziness degree, its major properties, and applications

    Ryjov, Alexander P.

    1992-01-01

    A model that makes use of fuzzy linguistic scales (FLS) is considered in this report. The definition of FLS fuzziness and its major properties are given in the report. Definitions that are concerned with information loss and noise are also presented.

  5. Psychometric Properties of the Teachers' Sense of Efficacy Scale within the Greek Educational Context

    Tsigilis, Nikolaos; Koustelios, Athanasios; Grammatikopoulos, Vasilios

    2010-01-01

    Many concerns have been raised about the validity of the existing instruments measuring teachers' efficacy. Recently, a new instrument to measure teachers' perceived efficacy has been presented, namely, the Teachers' Sense of Efficacy Scale (TSES). The purpose of the present study is to examine the psychometric properties of the TSES in the Greek…

  6. Factor Structure and Psychometric Properties of the Injection Phobia Scale-Anxiety

    Olatunji, Bunmi O.; Sawchuk, Craig N.; Moretz, Melanie W.; David, Bieke; Armstrong, Thomas; Ciesielski, Bethany G.

    2010-01-01

    The present investigation examined the factor structure and psychometric properties of the Injection Phobia Scale-Anxiety (IPS-Anx). Principal components analysis of IPS-Anx items in Study 1 (n = 498) revealed a 2-factor structure consisting of Distal Fear and Contact Fear. However, CFA results in Study 2 (n = 567) suggest that a 1-factor…

  7. Psychometric Properties of the "Reminiscence Functions Scale" for the Portuguese Population: A Preliminary Report

    Goncalves, Daniela C.; Guedes, Joana Martins; Fonseca, Antonio M.; Martin, Inacio

    2010-01-01

    The aim of the present study was to assess the psychometric properties of a version in Portuguese of the "Reminiscence Functions Scale." Total sample was composed of 628 participants aged between 18 and 92 years, divided into three groups according to their age (18-24 years, "n" = 249; 26-54 years, "n" = 174; 55 and older, "n" = 205). Results…

  8. Remarks on Some Mechanical Small-Scale Tests Applied to Properties of Materials

    Cardu, Marilena; Seccatore, Jacopo

    2016-06-01

    The paper presents the results of test campaigns on small-scale strength properties (particularly, micro-hardness) performed on two homogeneous materials: calcite, a very common and widespread mineral that is characterized by its relatively low Mohs hardness and its high reactivity with even weak acids; and glass, an amorphous solid characterized by the absence of the long-range order which defines crystalline materials. After a synthetic description of the principles underlying two of the three classical comminution laws, known as Kick's law and Rittinger's law, experimental results are discussed. The results of the tests performed show that both scale effect and size effect contribute to the non-constancy of mechanical properties at small scale for crystalline materials. On the other hand, for amorphous materials, a theoretical law considering size effects gives considerably different results from empirical measurements. Considerations and an extended discussion address these findings.

  9. Constraints on dark-matter properties from large-scale structure

    Kunz, Martin; Sawicki, Ignacy

    2016-01-01

    We use large-scale cosmological observations to place constraints on the dark matter pressure, sound speed and viscosity, and infer a limit on the mass of warm dark matter particles. Measurements of the cosmic microwave background (CMB) anisotropies constrain the equation of state and sound speed of the dark matter at last scattering at the per mille level. Since the redshifting of collisionless particles universally implies that these quantities scale like $a^{-2}$ absent shell crossing, we infer that today $w_{\\rm (DM)} 70$ eV, assuming it decoupled while relativistic around the same time as the neutrinos; for a cold relic, we show that $m>100$ eV. We separately constrain the properties of the DM fluid on linear scales at late times, and find upper bounds $c_{\\rm s, (DM)}^2<10^{-5.9}$, $c_{\\rm vis, (DM)}^{2} < 10^{-5.7}$, with no detection of non-dust properties for the DM.

  10. The scaling properties of stock markets based on modified multiscale multifractal detrended fluctuation analysis

    Lin, Aijing; Ma, Hui; Shang, Pengjian

    2015-10-01

    Here we propose the new method DH-MMA, based on multiscale multifractal detrended fluctuation analysis(MMA), to investigate the scaling properties in stock markets. It is demonstrated that our approach can provide a more stable and faithful description of the scaling properties in comprehensive range rather than fixing the window length and slide length. It allows the assessment of more universal and subtle scaling characteristics. We illustrate DH-MMA by selecting power-law artificial data sets and six stock markets from US and China. The US stocks exhibit very strong multifractality for positive values of q, however, the Chinese stocks show stronger multifractality for negative q than positive q. In general, the US stock markets show similar behaviors, but Chinese stock markets display distinguishing characteristics.

  11. Dynamical properties of fractal networks: Scaling, numerical simulations, and physical realizations

    This article describes the advances that have been made over the past ten years on the problem of fracton excitations in fractal structures. The relevant systems to this subject are so numerous that focus is limited to a specific structure, the percolating network. Recent progress has followed three directions: scaling, numerical simulations, and experiment. In a happy coincidence, large-scale computations, especially those involving array processors, have become possible in recent years. Experimental techniques such as light- and neutron-scattering experiments have also been developed. Together, they form the basis for a review article useful as a guide to understanding these developments and for charting future research directions. In addition, new numerical simulation results for the dynamical properties of diluted antiferromagnets are presented and interpreted in terms of scaling arguments. The authors hope this article will bring the major advances and future issues facing this field into clearer focus, and will stimulate further research on the dynamical properties of random systems

  12. Luminescence properties of II/VI semiconductor colloidal nanocrystals at collective and single scales

    Vion, Celine; Barthou, Carlos; Coolen, Laurent; Bennaloul, Paul; MaItre, Agnes [Institut des NanoSciences de Paris, Unite Mixte de Recherche-CNRS 7588, Universite Pierre et Marie Curie, Paris (France); Vu Duc Chinh; Pham Thuy Linh; Vu Thi Bich; Pham Thu Nga [Institute of Materials Science, Vietnam Academy of Science and Technology, Hanoi (Viet Nam)], E-mail: celine.vion@insp.jussieu.fr

    2009-09-01

    Colloidal nanocrystals are crystalline spheres of semiconductors of a few nanometers, obtained by chemical synthesis. At this size scale, lower than Bohr radius of the exciton, emission properties are dominated by quantum confinement effects and depend crucially on the nanocrystal radius, which can be controlled by adjusting the synthesis parameters. Nanocrystals present high photostability and good quantum efficiency, even at room temperature. Their emission wavelength can be tuned over the whole visible range, making them very attractive solid state light sources which are already used in optoelectronic devices or for biological labeling. The luminescence properties of CdSe colloidal nanocrystals synthesized at the Institute of Materials Science in Hanoi are presented. At collective scale, the emission properties reveal the synthesis quality. Temperature effects from ambient to 4 K on spectra and decay rates will be presented and analyzed in terms of emitting level fine structure. The study of CdSe colloidal quantum dots at the single emitter scale is of great interest as it reveals properties which are hidden by collective studies, such as luminescence 'blinking', a random switching from a fluorescent to a non fluorescent state, which is closely related to the crystalline defects of a nanocrystal and its interaction with its environment. We will present the blinking properties of the prepared nanocrystals, and relate them to the nanocrystals synthesis quality and shell quality.

  13. Thermophysical Properties of Lignocellulose: A Cell-scale Study down to 41K

    Cheng, Zhe; Zhang, Lei; Wang, Xinwei

    2014-01-01

    Thermal energy transport is of great importance in lignocellulose pyrolysis for bio-fuels. The thermophysical properties of lignocellulose significantly affect the overall properties of bio-composites and the related thermal transport. In this work, cell-scale lignocellulose (mono-layer plant cells) is prepared to characterize their thermal properties from room temperature down to 41 K. The thermal conductivities of cell-scale lignocellulose along different directions show a little anisotropy due to the cell structure anisotropy. It is found that with temperature going down, the volumetric specific heat of the lignocellulose shows a slower decreasing trend against temperature than that of microcrystalline cellulose, and its value is always higher than that of microcrystalline cellulose. The thermal conductivity of lignocellulose decreases with temperature from 243 K to 317 K due to increasing phonon-phonon scatterings. From 41 K to 243 K, the thermal conductivity rises with temperature and its change mainly d...

  14. Thermophysical properties of lignocellulose: a cell-scale study down to 41 K.

    Zhe Cheng

    Full Text Available Thermal energy transport is of great importance in lignocellulose pyrolysis for biofuels. The thermophysical properties of lignocellulose significantly affect the overall properties of bio-composites and the related thermal transport. In this work, cell-scale lignocellulose (mono-layer plant cells is prepared to characterize their thermal properties from room temperature down to ∼ 40 K. The thermal conductivities of cell-scale lignocellulose along different directions show a little anisotropy due to the cell structure anisotropy. It is found that with temperature going down, the volumetric specific heat of the lignocellulose shows a slower decreasing trend against temperature than microcrystalline cellulose, and its value is always higher than that of microcrystalline cellulose. The thermal conductivity of lignocellulose decreases with temperature from 243 K to 317 K due to increasing phonon-phonon scatterings. From 41 K to 243 K, the thermal conductivity rises with temperature and its change mainly depends on the heat capacity's change.

  15. The Influence of the Large-scale Environment on Galaxy Property

    Wei, Y. Q.; Wang, L.; Dai, C. P.

    2016-03-01

    The properties of star formation in galaxies and their dependence on environment play an important role in understanding the formation and evolution of galaxies.Using the galaxy sample of the Sloan Digital Sky Survey (SDSS), different groups have studied the physical property and the large-scale environment of galaxies. Here we use the filament catalog from Tempel et al. and classified galaxies catalog from Wang et al., considering the affect of shape of galaxies, high and low local density environment, and central (satellite) galaxies. It is found that the properties of galaxies and the large-scale environment are related: the SSFR (specific star formation rate) and SFR (star formation rate) strongly depend on large-scale environment only for spiral galaxies and satellite galaxies, but this dependence is very weak for elliptical galaxies and the central galaxies, and the influence of large-scale environment on galaxies in low density region is more sensitive than that in high density region. The above conclusion remains valid even for the galaxies with the same mass. In addition, the SSFR distributions from Tempel et al.'s catalog and Wang et al.'s catalog are not entirely consistent.

  16. Psychometric properties of the Turkish version of the internalized homophobia scale.

    Gençöz, Tülin; Yüksel, Murat

    2006-10-01

    The current study examined the psychometric properties of the Turkish version of the Internalized Homophobia Scale (IHS; Herek, Cogan, Gillis, & Glunt, 1997) in gay men living in Turkey. Participants were 132 men in romantic, intimate, or sexual relationships with men, and they identified themselves as homosexual (n=112) or bisexual (n=20). Alpha and split-half reliability coefficients revealed good internal consistency of the scale. Consistent with the original scale, the construct validity revealed a single factor for the scale. Regarding convergent validity, the IHS had significant correlations with psychological problems, particularly with symptoms of depression and anxiety; the scale also had a significant positive correlation with negative affect and a negative correlation with self-esteem. Regarding discriminant validity, the IHS had very low correlations with positive affect and hostility attitudes. The association between internalized homophobia and psychological problems remained significant even after controlling for the variance explained by self-esteem, negative affect, and positive affect. Hence, the psychometric properties of the Turkish version of IHS appear quite promising. PMID:17031586

  17. Multi-dimensional scattering properties diagnosis system of scale aircraft model in an anechoic chamber

    Chufeng Hu; Zhou Zhou; Nanjing Li; Kun Zhang

    2014-01-01

    Aiming at the concept of “diagnosis”, a simple and ef-fective broadband radar cross section (RCS) measurement system is constructed, and some multi-dimensional scattering properties diagnosis techniques are presented based on the system. Firstly, a stepped-frequency signal is employed to achieve high range resolution, combining with a variety of signal processing tech-niques. Secondly, cross-range resolution is gained with a rotating table, and the high-resolution two-dimensional (2-D) imaging of the scale model is obtained by the microwave imaging theory. Fi-nal y, two receiving antennas with a smal distance in altitude are used, and the three-dimensional (3-D) height distribution of scattering points on the scale model is extracted from the phase of images. Some typical bodies and a scale aircraft model are diagnosed in an anechoic chamber. The experimental results show that, after scaling with a metal sphere, the accurate one-dimensional (1-D) RCS pattern of the model is obtained, and it has a large dynamic range. When the bandwidth of the transmit-ting signal is 4 GHz, the resolution of the 2-D image can reach to 0.037 5 m. The 3-D height distribution of scattering points is given by interferometric measurement. This paper provides a feasible way to obtain high-precision scattering properties parameters of the scale aircraft model in a conventional rectangular anechoic chamber.

  18. Bayley-III Scales of Infant and Toddler Development: Transcultural Adaptation and Psychometric Properties

    Vanessa Madaschi

    2016-08-01

    Full Text Available Abstract Scales with evidence of validity and reliability are important to evaluate child development. In Brazil, there is a lack of standardized instruments to evaluate young children. This study investigated the psychometric properties of the Bayley Scales of Infant Development, Third Edition (Bayley-III. It was translated into Brazilian Portuguese, culturally adapted and tested on 207 children (12-42 months of age. Evidence of convergent validity was obtained from correlations of the Bayley-III with the: Peabody Developmental Motor Scale 2, Leiter International Performance Scale-R, Expressive Vocabulary Assessment List and Peabody Picture Vocabulary Test. Exploratory factor analyses showed a single component explaining 86% of the variance, supported by goodness-of-fit indexes in confirmatory factor analysis. The Bailey-III demonstrated good internal consistency with alpha coefficients greater than or equal to .90 and stability for fine motor scale only. These robust psychometric properties support the use of this tool in future national studies on child development.

  19. Investigating the elastic properties of sedimentary basins on different spatial scales

    Krause, Martin; Methe, Pascal; Goepel, Andreas; Bleibinhaus, Florian; Kukowski, Nina

    2014-05-01

    The study of subsurface fluid motion is important e.g. for understanding ground water motion or processes of compaction, diagenesis, and hydrocarbon migration in sedimentary basins. The multidisciplinary project INFLUINS (INtegrated FLUid dynamics IN Sedimentary basins) aims for investigating the coupled dynamics of near surface and deep fluid patterns and material transport in the Thuringian Basin (Germany). In order to gain information on how fluid flow processes depend on basin architecture, and therefore its physical properties, we first image the subsurface structure of the Thuringian Basin using seismic methods. Then, relations between hydraulic and elastic material parameters are required to also image the hydraulic structure of the basin's subsurface. As hydraulic properties often significantly vary with spatial scales, such a study requires a combination of small- to large-scale seismic data sets. In the framework of INFLUINS a variety of seismic data sets aiming for different subsurface parameters and spatial scales have been acquired. Basin scale seismic data sets are available from a set of 2D reflection seismic profiles as well as 2.5D and 3D seismic travel time tomography. Laboratory scale seismic data characterizing the basin's rocks is provided by ultrasound experiments on drill cores from the Thuringian Basin. Deep drilling conducted in the framework of INFLUINS in 2013 provides further useful data sets for our purpose: we acquired core material for laboratory ultrasound analysis and sonic-log data. As the drill site is located at the cross point of two seismic reflection profiles and also within the array of seismic stations we used for the 3D travel time tomography, it serves a direct transfer of elastic properties between different scales.

  20. Atomic-scale structure of grain boundaries: Correlations to grain boundary properties

    It is generally believed that many properties of solid interfaces are ultimately determined by their structure and composition at the atomic level. We report here on work in two areas of grain boundary (GB) research in which structure-property correlations have been investigated recently. HREM observations in connection with computer modeling of GBs in fcc metals have given considerable insight into correlations between GB energy and atomic-scale GB structure. Efforts to understand and possibly control the supercurrent transport behavior across GBs in high-temperature superconductors require the combination of microstructure characterizations with investigations of electric transport properties. In both areas considerable progress is being made and has already lead to important insights concerning interfacial properties

  1. Psychometric properties of the faces version of the Malay-modified child dental anxiety scale

    Esa, Rashidah; Hashim, Noratikah Awang; Ayob, Yuliana; Yusof, Zamros Yuzadi Mohd

    2015-01-01

    Background To evaluate the psychometric properties of the faces version of the Modified Child Dental Anxiety Scale (MCDASf) Malay version in 5–6 and 9–12 year-old children. Methods The MCDASf was cross culturally adapted from English into Malay. The Malay version was tested for reliability and validity in 3 studies. In the Study 1, to determine test-retest reliability of MCDASf scale, 166 preschool children aged 5–6 years were asked to rank orders five cartoons faces depicting emotions from ‘...

  2. Biomimic design of multi-scale fabric with efficient heat transfer property

    Fan Jie

    2012-01-01

    Full Text Available Wool fiber has a complex hierarchic structure. The multi-scale fibrils are assembled to form a tree-like channel net in wool fiber, providing an efficient heat transfer property. The optimal inner configuration of wool fiber can also be invited to biomimic design of textile fabrics to improve the thermal comfort of cloth. A heat transfer model of biomimic multi-scale fabric using the fractal derivative is established. Theoretical analysis indicates that the heat flux efficiency in the biomimic fabric can be 2 orders of magnitude comparing with that of the continuous medium.

  3. Psychometric properties of the finnish version of the resilience scale and its short version

    Heidi Losoi; Senni Turunen; Minna Wäljas; Mika Helminen; Juha Öhman; Juhani Julkunen; Eija Rosti-Otajärvi

    2013-01-01

    Aim: To investigate the psychometric properties of the Finnish version of the Resilience Scale (RS) and its short version (RS-14), as well as the relationship of resilience with demographic variables and self-perceived health. Method: A standard procedure was used for translation of the scale, and 243 participants (75% women, mean age = 41.0; SD = 17.8) were evaluated with the RS, the RS-14, and the EuroQol 5D. Results: The mean level of resilience was found to be moderate. Both the RS and th...

  4. Psychometric properties of the Revised Male Body Attitudes Scale among Irish men.

    Ryan, Travis A

    2011-01-01

    The psychometric properties of a revised version of the Male Body Attitudes Scale (Tylka, Bergeron, & Schwartz, 2005) were investigated using two independent online samples of Irish men (ns=241 and 253, respectively). Exploratory factor analyses suggested that a 15-item, 3-factor solution representing men\\'s attitudes toward their body fat, muscularity, and height best described the data. The internal consistency and construct validity of scores on the Revised Male Body Attitudes Scale suggest that this measure holds promise as an indicant of men\\'s attitudes toward their physical appearance. Limitations and strengths associated with the current research are discussed and directions for future research are outlined.

  5. Wavelength dependence of scattering properties in the VIS-NIR and links with grain-scale physical and compositional properties

    Pilorget, C.; Fernando, J.; Ehlmann, B. L.; Schmidt, F.; Hiroi, T.

    2016-03-01

    Surface scattered sunlight carries important information about the composition and microtexture of surface materials, thus enabling tracing back the geological and climatic processes that occurred on the planetary body. Here we perform laboratory spectro-goniometric measurements of granular samples (45-75 μ m fraction) with different composition and physical properties over the VIS-NIR spectral range (0.4-2.5 μ m). To quantify the evolution of the scattering properties over the VIS-NIR, we use an inversion procedure based on a Bayesian approach to estimate photometric parameters from the Hapke radiative transfer model. The granular samples are also carefully characterized by optical and SEM techniques in order to link these scattering variations with the grains' physical properties. Results show that the scattering properties are wavelength-dependent and can vary significantly over the VIS-NIR spectral range. In particular, the phase function of a granular material is affected by both the absorptivity and the external and internal structure of the grains, from the millimeter scale down to the wavelength scale. Our results also confirm that the macroscopic roughness parameter, as defined by Hapke, is to first order correlated with the absorptivity of the particles, through multiple scattering effects, and thus mostly corresponds to a measurement of the particles shadowing. Photometric datasets, typically obtained at a given wavelength that can vary from one study to another, should therefore be compared and interpreted with caution when extrapolating across wavelengths. Our results also suggest that multi-wavelength photometry could potentially provide a much richer signature than with single-wavelength photometry, opening new perspectives into the characterization of surface materials.

  6. Psychometric Properties of the Persian Version of Self-Transcendence Scale: Adolescent Version

    AzamShirinabadi Farahani

    2016-04-01

    Full Text Available Background: Given the greater tendency during adolescence toward risk-taking, identifying and measuring the factors affecting the adolescents’ health is highly important to ensure the efficacy of health promoting interventions. One of these factors is self-transcendence. The aim of this study was to assess the psychometric features of the Self-Transcendence Scale (adolescents’ version in students in Tehran, the capital city of Iran. Methods: This research was conducted in 2015. For this purpose, 1210 high school students were selected through the multistage cluster sampling method. After the backward-forward translation, the psychometric properties of the scale were examined through the assessment of the (face and construct validity and reliability (internal consistency and stability of the scale. The construct validity was assessed using two methods, factor analysis, and convergence of the scale with the Hopefulness Scale for Adolescents. Results: The result of face validity was minor modifications in some words. The exploratory factor analysis resulted in the extraction of two dimensions, with explaining 52.79% of the variance collectively. In determining the convergent validity, the correlation between hopefulness score and self-transcendence score was r=0.47 (P<0.001. The internal consistency of the scale was determined using Cronbach’s alpha of 0.82 for the whole scale and 0.75 and 0.70 for each of the sub-scales. The stability reliability was found to have an ICC of 0.86 and a confidence interval of 95%. Conclusion: The Persian version of the Adolescents’ Self-Transcendence Scale showed an acceptable validity and reliability and can be used in the assessment of self-transcendence in Iranian adolescents.

  7. Psychometric Properties of the Persian Version of Self-Transcendence Scale: Adolescent Version

    Farahani, Azam Shirinabadi; Rassouli, Maryam; Yaghmaie, Farideh; Majd, Hamid Alavi; Sajjadi, Moosa

    2016-01-01

    Background: Given the greater tendency during adolescence toward risk-taking, identifying and measuring the factors affecting the adolescents’ health is highly important to ensure the efficacy of health promoting interventions. One of these factors is self-transcendence. The aim of this study was to assess the psychometric features of the Self-Transcendence Scale (adolescents’ version) in students in Tehran, the capital city of Iran. Methods: This research was conducted in 2015. For this purpose, 1210 high school students were selected through the multistage cluster sampling method. After the backward-forward translation, the psychometric properties of the scale were examined through the assessment of the (face and construct) validity and reliability (internal consistency and stability) of the scale. The construct validity was assessed using two methods, factor analysis, and convergence of the scale with the Hopefulness Scale for Adolescents. Results: The result of face validity was minor modifications in some words. The exploratory factor analysis resulted in the extraction of two dimensions, with explaining 52.79% of the variance collectively. In determining the convergent validity, the correlation between hopefulness score and self-transcendence score was r=0.47 (P<0.001). The internal consistency of the scale was determined using Cronbach’s alpha of 0.82 for the whole scale and 0.75 and 0.70 for each of the sub-scales. The stability reliability was found to have an ICC of 0.86 and a confidence interval of 95%. Conclusion: The Persian version of the Adolescents’ Self-Transcendence Scale showed an acceptable validity and reliability and can be used in the assessment of self-transcendence in Iranian adolescents. PMID:27218113

  8. Scale-free and small-world properties of earthquake network in Chile

    Pasten, Denisse; Munoz, Victor; Suzuki, Norikazu

    2010-01-01

    The properties of earthquake networks have been studied so far mainly for the seismic data sets taken from California, Japan and Iran, and features common in these regions have been reported in the literature. Here, an earthquake network is constructed and analyzed for the Chilean data to examine if the scale-free and small-world properties of the earthquake networks constructed in the other geographical regions can also be found in seismicity in Chile. It is shown that the result is affirmative: in all the regions both the exponent "gamma" of the power-law connectivity distribution and the clustering coefficient C take the universal invariant values "gamma ~1" and "C~0.85", respectively, as the cell size becomes larger than a certain value, which is the scale of coarse graining needed for constructing earthquake network. An interpretation for this remarkable result is presented based on physical considerations.

  9. Ionic conduction in solids: Comparing conductivity and modulus representations with regard to scaling properties

    In the literature, the electric modulus representation has been used to provide comparative analysis of the ion transport properties in different ion-conducting materials. In this paper we show that the modulus representation is not a suitable tool for such purposes. Our arguments derive from an examination of the scaling properties of both the ac conductivity σ*(ν) and the modulus M*(ν) which demonstrates how scaling that is inherent in σ*(ν) is lost in M*(ν) by inclusion of the high frequency permittivity ε'(∞), the latter quantity being unrelated to ion transport processes. Furthermore, we show how highly regarded shape changes of the modulus that occur with varying ion concentration are merely a manifestation of including ε'(∞) in the definition of M*(ν). We conclude then that the electric modulus formalism has resulted in misleading interpretations of the ion dynamics and, hence, should be discouraged

  10. Psychometric properties of the Drive for Muscularity Scale in Malay men.

    Swami, Viren; Barron, David; Lau, Poh Li; Jaafar, Jas Laile

    2016-06-01

    The Drive for Muscularity Scale (DMS) is a widely used measure in studies of men's body image, but few studies have examined its psychometric properties outside English-speaking samples. Here, we assessed the factor structure of a Malay translation of the DMS. A community sample of 159 Malay men from Kuala Lumpur, Malaysia, completed the DMS, along with measures of self-esteem, body appreciation, and muscle discrepancy. Exploratory factor analysis led to the extraction of two factors, differentiating attitudes from behaviours, which mirrors the parent scale. Both factors also loaded on to a higher-order drive for muscularity factor. The subscales of the Malay DMS had adequate internal consistencies and good convergent validity, insofar as significant relationships were reported with self-esteem, body appreciation, muscle discrepancy, and body mass index. These results indicate that the Malay DMS has acceptable psychometric properties and can be used to assess body image concerns in Malay men. PMID:27037873

  11. Thermal properties at Aespoe HRL. Analysis of distribution and scale factors

    A thermal model for the Aespoe HRL as well as a general strategy for thermal modelling is under development. As a part of that work, thermal conductivities have been modelled from reference values of thermal conductivity of different minerals and from the mineral composition of all Aespoe samples in the Sicada database. The produced thermal conductivity database has been analysed in terms of frequency, type of distribution, spatial distribution, variogram etc. A correction factor has been estimated to compensate for discrepancies between measured and calculated values. The calculated values have been corrected according to measured values. The data has been analysed according to different rock types. However, there are uncertainties in the base material of rock classification, mainly due to problem to distinguish between Aespoe diorite and Aevroe granite, but also because of different classification systems. There is a relationship between thermal conductivity and density for the rock types at Aespoe. Equations of the relationship have been developed based on all thermal conductivity, heat capacity and density measurements. The equations have been tested on two bore holes at Aespoe with promising results. It may be possible to evaluate the spatial distribution of the thermal properties from density loggings. However, more work is needed to develop a complete model including the handling of high and low density zones. There is an insufficient knowledge in the variation of thermal properties at different scales. If the whole variation within a rock type is in the cm-m scale the thermal influence on the canister is small. This is due to the fact that the small-scale variation in thermal properties is mainly averaged out in the 5-10 m scale. If the main variation within rock types is in the 5-10 m scale there is probably a significant effect on the canister temperature. However, it is likely that the observed variation occurs in both these scales. Simulation has been

  12. The impact of dust on the scaling properties of galaxy clusters

    da Silva, Antonio C.; Catalano, Andrea; Montier, Ludovic; Pointecouteau, Etienne; Lanoux, Joseph; Giard, Martin

    2008-01-01

    We investigate the effect of dust on the scaling properties of galaxy clusters based on hydrodynamic N-body simulations of structure formation. We have simulated five dust models plus a radiative cooling and adiabatic models using the same initial conditions for all runs. The numerical implementation of dust was based on the analytical computations of Montier and Giard (2004). We set up dust simulations to cover different combinations of dust parameters that put in evidence the effects of siz...

  13. Pilot study of the psychometric properties of the Emotional Exhaustion Scale for university students

    Fontana, Silvia Alicia

    2011-01-01

    The stated goal is to analyze the psychometric properties of the Emotional Exhaustion Scale (EES) (González-Ramírez and Landero-Hernández, 2007) in university students in Argentina. The results obtained in the EES were the verification of the unifactorial structure (KMO = .880; test of sphericity of Barttlet = 568,59, p< .001) and a high level of reliability (α = .86).

  14. Psychometric properties of the satisfaction with life scale (SWLS) in Iranian infertile women

    Maroufizadeh, Saman; Ghaheri, Azadeh; Omani Samani, Reza; Ezabadi, Zahra

    2016-01-01

    Background: Infertility is a global public health issue and may adversely affect life satisfaction. One of the most widely instruments used to assess life satisfaction is the Satisfaction with Life Scale (SWLS). Objective: The objective of this study was to examine the psychometric properties of the SWLS in Iranian infertile women. Materials and Methods: In this descriptive cross-sectional study, a total of 125 infertile women referring to Royan Institute in Tehran were selected by convenienc...

  15. Estimating local scaling properties for the classification of interstitial lung disease patterns

    Huber, Markus B.; Nagarajan, Mahesh B.; Leinsinger, Gerda; Ray, Lawrence A.; Wismueller, Axel

    2011-03-01

    Local scaling properties of texture regions were compared in their ability to classify morphological patterns known as 'honeycombing' that are considered indicative for the presence of fibrotic interstitial lung diseases in high-resolution computed tomography (HRCT) images. For 14 patients with known occurrence of honeycombing, a stack of 70 axial, lung kernel reconstructed images were acquired from HRCT chest exams. 241 regions of interest of both healthy and pathological (89) lung tissue were identified by an experienced radiologist. Texture features were extracted using six properties calculated from gray-level co-occurrence matrices (GLCM), Minkowski Dimensions (MDs), and the estimation of local scaling properties with Scaling Index Method (SIM). A k-nearest-neighbor (k-NN) classifier and a Multilayer Radial Basis Functions Network (RBFN) were optimized in a 10-fold cross-validation for each texture vector, and the classification accuracy was calculated on independent test sets as a quantitative measure of automated tissue characterization. A Wilcoxon signed-rank test was used to compare two accuracy distributions including the Bonferroni correction. The best classification results were obtained by the set of SIM features, which performed significantly better than all the standard GLCM and MD features (p < 0.005) for both classifiers with the highest accuracy (94.1%, 93.7%; for the k-NN and RBFN classifier, respectively). The best standard texture features were the GLCM features 'homogeneity' (91.8%, 87.2%) and 'absolute value' (90.2%, 88.5%). The results indicate that advanced texture features using local scaling properties can provide superior classification performance in computer-assisted diagnosis of interstitial lung diseases when compared to standard texture analysis methods.

  16. Development and Datametric Properties of a Scale Measuring Students' Perceptions of The Classroom Assessment Environment

    Hussain Alkharusi

    2011-01-01

    Each classroom has its own assessment environment perceived by the students and springs from the teacher's assessment practices. Although students' perceptions of the assessment environment may influence their achievement-related outcomes, little attention has been given to the measurement of perceived classroom assessment environment. This study reports on the development and datametric properties of a scale measuring students' perceptions of the classroom assessment environment. A total of ...

  17. Scale-free and multifractal properties of fMRI signals during rest and task

    PhilippeCIUCIU

    2012-06-01

    Full Text Available Scale-free (or 1/f spectral properties in functional MRI (fMRI signals have been evidenced for a decade as intrinsic characteristics of ongoing brain activity [46]. Recently, they were shown to fluctuate across brain networks and to be modulated between rest and task [26]: Notably, Hurst exponent, quantifying long memory, decreases during task in activating and deactivating brain regions. Such results were obtained using tools assuming Gaussianity and self-similar models, while fMRI signals may significantly depart from those two assumptions [16] and were often based on voxelwise or regionwise independent analysis, hence showing large inter-subject variability. The present article aims at contributing to the analysis of scale-free properties of fMRI signals in two respects. First, a recent statistical analysis tool, the Wavelet Leader-based Multifractal formalism (WLMF, is used [45,3]. It shows improved estimation performance, and it is framed within a richer and more versatile class of models, that of multifractal processes. Second, scale-free properties are not investigated at the voxel or region scale. Instead, resting-state brain networks are extracted using a Multi-Subject Dictionary Learning (MSDL algorithm [40]: It produces both a set of spatial components, and a set of times series, for each component and each subject, that conveys ongoing dynamics in functional networks but also in artifacts. These combined tools are applied to an fMRI dataset comprising 12-subjects with resting-state and activation runs [36]. This dataset enabled us to confirm the task-related decrease of long memory in functional networks but also in artifacts making this feature not specific to functional networks. Also, most of fMRI signals appear multifractal at rest except in non-cortical regions. Task-related modulation of multifractality appears only significant in functional networks and thus becomes the key property to disentangle functional networks from

  18. Development and Psychometric Properties of the Yoga Self-Efficacy Scale (YSES)

    Birdee, Gurjeet S.; Sohl, Stephanie J.; Wallston, Ken

    2016-01-01

    Background Yoga is a behavioral practice that uses physical movement, breathing, and meditation to improve health and promote personal transformation. Ancient yoga philosophy proposed that an individual’s confidence about yoga, a concept similar to self-efficacy, will affect the likelihood of improved health from yoga practice. The purpose of this study was to develop and examine the psychometric properties of a self-efficacy measure for yoga practice (the Yoga Self-Efficacy Scale; YSES). Met...

  19. The MUSIC of Galaxy Clusters II: X-ray global properties and scaling relations

    Biffi, Veronica; De Petris, Marco; Valdarnini, Riccardo; Yepes, Gustavo; Gottlöber, Stefan

    2014-01-01

    We present the X-ray properties and scaling relations of a large sample of clusters extracted from the Marenostrum MUltidark SImulations of galaxy Clusters (MUSIC) dataset. We focus on a sub-sample of 179 clusters at redshift z~0.11, with 3.2e14M_sun/hproperties of the intracluster medium (ICM), as X-ray temperature (T_X) and luminosity (L_X). T_X is found to slightly under-estimate the true mass-weighted temperature, although tracing fairly well the cluster total mass. We also study the effects of T_X on scaling relations with cluster intrinsic properties: total (M_500) and gas (M_g500) mass; integrated Compton parameter (Y_SZ) of the Sunyaev-Zel'dovich (SZ) thermal effect; Y_X=M_g500 T_X. We confirm that Y_X is a very good mass proxy, with a scatter on M_500-Y_X and Y_SZ-Y_X lower than 5%. The study of scaling relations among X-ray, intrinsic and S...

  20. Scaling Properties of Rainfall-Induced Landslides Predicted by a Physically Based Model

    Alvioli, M; Rossi, M

    2013-01-01

    Natural landslides exhibit scaling properties, including the frequency of the size of the landslides, and the rainfall conditions responsible for landslides. Reasons for the scaling behavior of landslides are poorly known, and only a few attempts were made to describe the empirical evidences of the self-similar scaling behavior of landslides with physically based models. We investigate the possibility of using the TRIGRS code, a consolidated, physically motivated, numerical model to describe the stability conditions of natural slopes forced by rainfall, to determine the frequency of the area of the unstable slopes and the rainfall intensity-duration (I-D) conditions that result in landslides in a region.We apply TRIGRS in a portion of the Upper Tiber River Basin, Central Italy. The spatially distributed model predicts the stability conditions of individual grid cells, given the terrain and rainfall conditions. We run TRIGRS using multiple rainfall histories, and we compare the results to empirical evidences o...

  1. Psychometric Properties of the Parent and Teacher ADHD Rating Scale (ADHD-RS)

    Makransky, Guido; Bilenberg, Niels

    2014-01-01

    Attention deficit/hyperactivity disorder (ADHD) is one of the most common psychiatric disorders in childhood and adolescence. Rating the severity of psychopathology and symptom load is essential in daily clinical practice and in research. The parent and teacher ADHD-Rating Scale (ADHD-RS) includes...... inattention and hyperactivity/impulsivity subscales and is one of the most frequently used scales in treatment evaluation of children with ADHD. An extended version, mADHD-RS, also includes an oppositional defiant disorder subscale. The partial credit Rasch model, which is based on item response theory, was...... used to test the psychometric properties of this scale in a sample of 566 Danish school children between 6 and 16 years of age. The results indicated that parents and teachers had different frames of reference when rating symptoms in the mADHD-RS. There was support for the unidimensionality of the...

  2. The necessary and sufficient conditions for returns to scale properties in generalized data envelopment analysis model

    WEI; Quanling(魏权龄); YU; Gang(于刚); LU; Jianshou(陆剑受)

    2002-01-01

    We give definitions on increasing, constant and decreasing returns to scale under thegeneralized data envelopment analysis (GDEA) model. The GDEA model possesses cone structures fordescribing evaluators' preferences toward different decision making units (DMU) and toward differentinput/output categories. The GDEA model contains many important DEA models as its subclasses.Based upon the definition, we discuss and rigorously prove the necessary and sufficient conditionsfor a DMU to have increasing, constant and decreasing returns to scale under a GDEA model, anddiscuss and clarify the differences and relationships of these conditions under different subclasses ofthe GDEA model. Furthermore, we describe a method based on a two-stage linear program to testreturns to scale properties.

  3. Tabulated In-Drift Geometric and Thermal Properties Used In Drift-Scale Models for TSPA-SR

    The objective of this calculation is to provide in-drift physical properties required by the drift-scale models (both two- and three-dimensional) used in total system performance assessments (TSPA). The physical properties include waste package geometry, waste package thermal properties, emplacement drift geometry including backfill and invert geometry and properties (both thermal and hydrologic), drip shield geometry and thermal properties, all tabulated in a single source

  4. Effect of personality item writing on psychometric properties of ideal-point and likert scales.

    Huang, Jialin; Mead, Alan D

    2014-12-01

    The present study was designed to investigate personality item-writing practices and their effect on the psychometric properties of personality items and scales. Personality items were developed based on ideal-point and dominance models, analyzed using the generalized graded unfolding model, and empirically classified as having an ideal-point or dominance form. Results suggested that writing dominance items were slightly easier (more successful) than writing ideal-point items, but this varied slightly by personality dimensions. Of 3 ideal-point item writing tactics, the "neutral" tactic was least successful; success writing "double-barreled" and "average" ideal-point items was comparable to that of dominance items. Three personality scales were then constructed using successful ideal-point and dominance items. Scales constructed using ideal-point items had substantially inferior psychometric properties, including lower score reliability, lower correlations with important criteria, and mixed test information results. However, lower predictive validity of ideal-point scale scores may be due to lower reliability of the scores. Practical and methodological implications were also discussed. (PsycINFO Database Record (c) 2014 APA, all rights reserved). PMID:24999752

  5. Effects of galactic disc inclination and resolution on observed GMC properties and Larson's scaling relations

    Pan, Hsi-An; Fujimoto, Yusuke; Tasker, Elizabeth J.; Rosolowsky, Erik; Colombo, Dario; Benincasa, Samantha M.; Wadsley, James

    2016-05-01

    With ALMA (Atacama Large Millimeter/submillimeter Array) making it possible to resolve giant molecular clouds (GMCs) in other galaxies, it is becoming necessary to quantify the observational bias on measured GMC properties. Using a hydrodynamical simulation of a barred spiral galaxy, we compared the physical properties of GMCs formed in position-position-position (PPP) space to the observational position-position-velocity (PPV) space. We assessed the effect of disc inclination: face-on (PPVface) and edge-on (PPVedge), and resolution: 1.5 pc versus 24 pc, on GMC properties and the further implications of using Larson's scaling relations for mass-radius and velocity dispersion-radius. The low-resolution PPV data are generated by simulating ALMA Cycle 3 observations using the CASA package. Results show that the median properties do not differ strongly between PPP and PPVface under both resolutions, but PPVedge clouds deviate from these two. The differences become magnified when switching to the lower, but more realistic resolution. The discrepancy can lead to opposite results for the virial parameter's measure of gravitational binding, and therefore the dynamical state of the clouds. The power-law indices for the two Larson's scaling relations decrease going from PPP, PPVedge to PPVface and decrease from high to low resolutions. We conclude that the relations are not entirely driven by the underlying physical origin and therefore have to be used with caution when considering the environmental dependence, dynamical state, and the extragalactic CO-to-H2 conversion factor of GMCs.

  6. Atomic scale properties of magnetic Mn-based alloys probed by Emission Mössbauer spectroscopy

    Mn-based alloys are characterized by a wealth of properties, which are of interest both from fundamental physics point of view and particularly attractive for different applications in modern technology: from magnetic storage to sensing and spin-based electronics. The possibility to tune their magnetic properties through post-growth thermal processes and/or stoichiometry engineering is highly important in order to target different applications (i.e. Mn$_{x}$Ga) or to increase their Curie temperature above room temperature (i.e. off-stoichiometric MnSi). In this project, the Mössbauer effect will be applied at $^{57}$Fe sites following implantation of radioactive $^{57}$Mn, to probe the micro-structure and magnetism of Mn-based alloys at the most atomic-scale. The proposed experimental plan is devoted to establish a direct correlation between the local structure and bulk magnetism (and other physical properties) of Mn-based alloys.

  7. Dependency structure and scaling properties of financial time series are related

    Morales, Raffaello; Di Matteo, T.; Aste, Tomaso

    2014-04-01

    We report evidence of a deep interplay between cross-correlations hierarchical properties and multifractality of New York Stock Exchange daily stock returns. The degree of multifractality displayed by different stocks is found to be positively correlated to their depth in the hierarchy of cross-correlations. We propose a dynamical model that reproduces this observation along with an array of other empirical properties. The structure of this model is such that the hierarchical structure of heterogeneous risks plays a crucial role in the time evolution of the correlation matrix, providing an interpretation to the mechanism behind the interplay between cross-correlation and multifractality in financial markets, where the degree of multifractality of stocks is associated to their hierarchical positioning in the cross-correlation structure. Empirical observations reported in this paper present a new perspective towards the merging of univariate multi scaling and multivariate cross-correlation properties of financial time series.

  8. Deep Acting and Surface Acting Scale (DASAS – Adaptation of the metod and preliminary psychometric properties

    Maria Finogenow

    2015-07-01

    Full Text Available Background: This article presents the results of the study on the Polish version of the revised Emotional Labor Scale (ELS, developed by Lee and Brotheridge. The ELS measures deep acting and 2 aspects of surface acting (hiding feelings and faking emotions. Material and Methods: Psychometric characteristics of the Polish version of the ELS, named Deep Acting and Surface Acting Scale (DASAS, were analyzed in the preliminary study on 332 people working in various service professions. We verified factor structure of the scale, its reliability, and construct validity (that is, the relationships between its subscales and other measures of workplace functioning. Results: The results indicated that the DASAS has good psychometric properties which are comparable with the characteristics of the original scale. We replicated a 3-factor structure of the scale and confirmed its satisfying internal consistency and construct validity. Conclusions: The preliminary findings suggest that the DASAS is an adequate measure of deep and surface acting. Med Pr 2015;66(3:359–371

  9. Microstructure, mechanical, and biomimetic properties of fish scales from Pagrus major.

    Ikoma, Toshiyuki; Kobayashi, Hisatoshi; Tanaka, Junzo; Walsh, Dominic; Mann, Stephen

    2003-06-01

    The fish scale of Pagrus major has an orthogonal plywood structure of stratified lamellae, 1-2 microm in thickness, consisting of closely packed 70- to 80-nm-diameter collagen fibers. X-ray diffraction, energy-dispersive X-ray analysis, and infrared spectroscopy indicate that the mineral phase in the scale is calcium-deficient hydroxyapatite containing a small amount of sodium and magnesium ions, as well as carbonate anions in phosphate sites of the apatite lattice. The tensile strength of the scale is high (approximately 90 MPa) because of the hierarchically ordered structure of mineralized collagen fibers. Mechanical failure occurs by sliding of the lamellae and associated pulling out and fracture of the collagen fibers. In contrast, demineralized scales have significantly lower tensile strength (36 MPa), indicating that interactions between the apatite crystals and collagen fibers are of fundamental importance in determining the mechanical properties. Thermal treatment of fish scales to remove the organic components produces remarkable inorganic replicas of the native orthogonal plywood structure of the fibrillary plate. The biomimetic replica produced by heating to 873 K consists of stratified porous lamellae of c-axis-aligned apatite crystals that are long, narrow plates, 0.5-0.6 microm in length and 0.1-0.2 microm in width. The textured inorganic material remains intact when heated to 1473 K, although the size of the constituent crystals increases as a result of thermal sintering. PMID:12781659

  10. A Brief Scale to Measure Problematic Sexually Explicit Media Consumption: Psychometric Properties of the Compulsive Pornography Consumption (CPC) Scale among Men who have Sex with Men

    Noor, Syed WB; Simon Rosser, B. R.; Erickson, Darin J.

    2015-01-01

    Although the phenomenon of hypersexuality has been described in the literature, and scales of compulsive sexual behavior have been published, the existing measures do not assess compulsive sexually explicit media (SEM) consumption. This study tested the psychometric properties of a new scale, the Compulsive Pornography Consumption (CPC). Exploratory and confirmatory factor analyses results showed good psychometric performance of a five item two factor preoccupation-compulsivity solution. As hypothesized, the scale correlates positively with compulsive sexual behavior, internalized homonegativity, and negatively with sexual self-esteem. The scale will enable researchers to investigate the etiologic factors of compulsive SEM use, and enable clinicians to assess problematic consumption. PMID:25838755

  11. Bio-inspired dual surface modification to improve tribological properties at small-scale

    Singh, R. Arvind; Pham, Duc-Cuong; Kim, Jinseok; Yang, Sungwook; Yoon, Eui-Sung

    2009-02-01

    In miniaturized devices like micro/nano-electro-mechanical systems (MEMS/NEMS), the critical forces, namely adhesion and friction restrict the smooth operation of the elements that are in relative motion. MEMS/NEMS are traditionally made of silicon, whose tribological properties are not good. In this paper, we present an investigation on the approach of dual surface modification of silicon surfaces and their tribological properties at micro-scale. The dual surface modification is a combination of topographical and chemical modifications. As the topographical modification, micro-patterns with varying shapes of pillars and channels were fabricated on Si(1 0 0) wafer surfaces using photolithography method. Chemical modification included the coating of micro-patterns with diamond-like carbon (DLC) and Z-DOL (perfluoropolyether, PFPE) thin films. The surfaces with combined modification were evaluated for their micro-friction behavior in comparison with those of bare Si(1 0 0) flat surfaces and the topographically/chemically modified silicon surfaces. Results showed that the surfaces with dual modification exhibited superior tribological properties. These results indicate that a combination of topographical and chemical modification is very effective in enhancing tribological properties at small-scale. The combined surface treatments such as the ones investigated in the current work could be useful for tribological applications in small-scale devices such as MEMS/NEMS. The motivation for undertaking the dual modification approach comes from an earlier observation made on the significant influence of the surface characteristics of lotus leaf on its micro-friction behavior.

  12. Biome-Scale Forest Properties in Amazonia Based on Field and Satellite Observations

    Liana O. Anderson

    2012-05-01

    Full Text Available Amazonian forests are extremely heterogeneous at different spatial scales. This review intends to present the large-scale patterns of the ecosystem properties of Amazonia, and focuses on two parts of the main components of the net primary production: the long-lived carbon pools (wood and short-lived pools (leaves. First, the focus is on forest biophysical properties, and secondly, on the macro-scale leaf phenological patterns of these forests, looking at field measurements and bringing into discussion the recent findings derived from remote sensing dataset. Finally, I discuss the results of the three major droughts that hit Amazonia in the last 15 years. The panorama that emerges from this review suggests that slow growing forests in central and eastern Amazonia, where soils are poorer, have significantly higher above ground biomass and higher wood density, trees are higher and present lower proportions of large-leaved species than stands in northwest and southwest Amazonia. However, the opposite pattern is observed in relation to forest productivity and dynamism, which is higher in western Amazonia than in central and eastern forests. The spatial patterns on leaf phenology across Amazonia are less marked. Field data from different forest formations showed that new leaf production can be unrelated to climate seasonality, timed with radiation, timed with rainfall and/or river levels. Oppositely, satellite images exhibited a large-scale synchronized peak in new leaf production during the dry season. Satellite data and field measurements bring contrasting results for the 2005 drought. Discussions on data processing and filtering, aerosols effects and a combined analysis with field and satellite images are presented. It is suggested that to improve the understanding of the large-scale patterns on Amazonian forests, integrative analyses that combine new technologies in remote sensing and long-term field ecological data are imperative.

  13. Constraints on dark-matter properties from large-scale structure

    Kunz, Martin; Nesseris, Savvas; Sawicki, Ignacy

    2016-07-01

    We use large-scale cosmological observations to place constraints on the dark-matter pressure, sound speed and viscosity and infer a limit on the mass of warm-dark-matter particles. Measurements of the cosmic microwave background anisotropies constrain the equation of state and sound speed of the dark matter (DM) at last scattering at the per mille level. Since the redshifting of collisionless particles universally implies that these quantities scale like a-2 absent shell crossing, we infer that today w(DM )dark-matter models: For warm dark matter these constraints imply m >70 eV , assuming it decoupled while relativistic around the same time as the neutrinos; for a cold relic, we show that m >100 eV . We separately constrain the properties of the DM fluid on linear scales at late times and find upper bounds cs,(DM ) 2<1 0-5.9 and cvis,(DM) 2<1 0-5.7 , with no detection of nondust properties for the DM.

  14. Psychometric properties and construct validity of the Muscle Appearance Satisfaction Scale among Hungarian men.

    Babusa, Bernadett; Urbán, Róbert; Czeglédi, Edit; Túry, Ferenc

    2012-01-01

    Limited studies have evaluated the psychometric properties of the Muscle Appearance Satisfaction Scale (MASS), a measure of muscle dysmorphia, in different cultures and languages. The aims were to examine the psychometric properties of the Hungarian version of the MASS (MASS-HU), and to investigate its relationship with self-esteem and exercise-related variables. Two independent samples of male weight lifters (ns=289 and 43), and a sample of undergraduates (n=240) completed the MASS, Eating Disorder Inventory, and Rosenberg Self-esteem Scale. Exploratory factor analysis supported the original five-factor structure of the MASS only in the weight lifter sample. The MASS-HU had excellent scale score reliability and good test-retest reliability. The construct validity of the MASS-HU was tested with multivariate regression analyses which indicated an inverse relationship between self-esteem and muscle dysmorphia. The 18-item MASS-HU was found to be a useful measure for the assessment of muscle dysmorphia among male weight lifters. PMID:21962394

  15. Some psychometric properties of the Chinese version of the Modified Dental Anxiety Scale with cross validation

    Lahti Satu

    2008-03-01

    Full Text Available Abstract Objective To assess the factorial structure and construct validity for the Chinese version of the Modified Dental Anxiety Scale (MDAS. Materials and methods A cross-sectional survey was conducted in March 2006 from adults in the Beijing area. The questionnaire consisted of sections to assess for participants' demographic profile and dental attendance patterns, the Chinese MDAS and the anxiety items from the Hospital Anxiety and Depression Scale (HADS. The analysis was conducted in two stages using confirmatory factor analysis and structural equation modelling. Cross validation was tested with a North West of England comparison sample. Results 783 questionnaires were successfully completed from Beijing, 468 from England. The Chinese MDAS consisted of two factors: anticipatory dental anxiety (ADA and treatment dental anxiety (TDA. Internal consistency coefficients (tau non-equivalent were 0.74 and 0.86 respectively. Measurement properties were virtually identical for male and female respondents. Relationships of the Chinese MDAS with gender, age and dental attendance supported predictions. Significant structural parameters between the two sub-scales (negative affectivity and autonomic anxiety of the HADS anxiety items and the two newly identified factors of the MDAS were confirmed and duplicated in the comparison sample. Conclusion The Chinese version of the MDAS has good psychometric properties and has the ability to assess, briefly, overall dental anxiety and two correlated but distinct aspects.

  16. Diffusion in time-dependent random environments: mass fluctuations and scaling properties

    A mass-ejection model in a time-dependent random environment with both temporal and spatial correlations is introduced. When the environment has a finite correlation length, individual particle trajectories are found to diffuse at large times with a displacement distribution that approaches a Gaussian. The collective dynamics of diffusing particles reaches a statistically stationary state, which is characterized in terms of a fluctuating mass density field. The probability distribution of density is studied numerically for both smooth and non-smooth scale-invariant random environments. Competition between trapping in the regions where the ejection rate of the environment vanishes and mixing due to its temporal dependence leads to large fluctuations of mass. These mechanisms are found to result in the presence of intermediate power-law tails in the probability distribution of the mass density. For spatially differentiable environments, the exponent of the right tail is shown to be universal and equal to -3/2. However, at small values, it is found to depend on the environment. Finally, spatial scaling properties of the mass distribution are investigated. The distribution of the coarse-grained density is shown to possess some rescaling properties that depend on the scale, the amplitude of the ejection rate and the Hölder exponent of the environment. (paper)

  17. Pre-scaled two-parameter Gauss-Newton image reconstruction to reduce property recovery imbalance

    Gauss-Newton image reconstruction in microwave imaging can be formulated in terms of a single complex quantity, the wave number squared (k2), with the understanding that the relative permittivity and conductivity images can be extracted afterwards through a simple constitutive relationship. However, this approach ignores the fact that the magnitude of the average real and imaginary components can be considerably out of balance depending on the operating frequency and tissue characteristics which can inadvertently imbalance the process in favour of one parameter over the other. In an effort to achieve property recovery which is balanced, we introduce a pre-scaling procedure at the property update stage of the reconstruction. Utilization of this concept in conjunction with our two-step regularization process for both simulation and phantom experiments demonstrates that the penalty term weighting parameters for the optimal mean-squared property errors for the two recovered distributions (relative permittivity and conductivity) together with that yielding the lowest least-squared electric field error coincide only when the scaling is applied. The scheme provides a means for simultaneous optimization of the two permittivity and conductivity images. (author)

  18. Ecosystem functional properties - useful links to organism and to global scale?

    Reichstein, M.

    2015-12-01

    Classical biogeographical observations tell us that ecosystems (vegetation and soils) strongly respond to climate variation in terms of their structure and function. On the other hand the influence of vegetation function on climate via exchange of matter and energy with the atmosphere has become evident in the last decades via observational and modeling studies. Recent continuous observations of this exchange of CO2, H2O and sensible heat within the global observation network FLUXNET have enabled us to quantify ecosystem function in response to large eco-climatological spatio-temporal variability of climate. We see that ecosystem function co-varies strongly with climate, but that climate alone does not suffice to explain the variation in total. Instead vegetation biophysical and structural parameters co-determine the exchange of carbon, water and energy between the ecosystem and the atmosphere. By combining ecosystem level observation and information of spatial meteorological and vegetation remote sensing covariates we can infer global patterns of ecosystem atmosphere fluxes and derive key ecosystem functional properties globally. While this approach is powerful and meteorological and vegetation structural predictors explain more than 70% of the spatial variation of monthly fluxes at FLUXNET sites, it ignores the effect of ecophysiological vegetation properties, which is expected from plant physiological leaf or whole-plant studies. Hence, future research has to more strongly link the organismic trait information with ecosystem functional properties. For this we propose a framework that involves 1) the correlation of community aggregated traits with flux-derived ecosystem properties across a range of ecosystems, 2) the up-scaling of vegetation traits using spatially distributed geo-ecological co-variates and the comparison with global ecosystem functional properties and their co-variation with climate, 3) the use of vegetation traits instead of vegetation classes

  19. What drives basin scale spatial variability of snowpack properties in northern Colorado?

    Sexstone, G. A.; Fassnacht, S. R.

    2014-03-01

    This study uses a combination of field measurements and Natural Resource Conservation Service (NRCS) operational snow data to understand the drivers of snow density and snow water equivalent (SWE) variability at the basin scale (100s to 1000s km2). Historic snow course snowpack density observations were analyzed within a multiple linear regression snow density model to estimate SWE directly from snow depth measurements. Snow surveys were completed on or about 1 April 2011 and 2012 and combined with NRCS operational measurements to investigate the spatial variability of SWE near peak snow accumulation. Bivariate relations and multiple linear regression models were developed to understand the relation of snow density and SWE with terrain variables (derived using a geographic information system (GIS)). Snow density variability was best explained by day of year, snow depth, UTM Easting, and elevation. Calculation of SWE directly from snow depth measurement using the snow density model has strong statistical performance, and model validation suggests the model is transferable to independent data within the bounds of the original data set. This pathway of estimating SWE directly from snow depth measurement is useful when evaluating snowpack properties at the basin scale, where many time-consuming measurements of SWE are often not feasible. A comparison with a previously developed snow density model shows that calibrating a snow density model to a specific basin can provide improvement of SWE estimation at this scale, and should be considered for future basin scale analyses. During both water year (WY) 2011 and 2012, elevation and location (UTM Easting and/or UTM Northing) were the most important SWE model variables, suggesting that orographic precipitation and storm track patterns are likely driving basin scale SWE variability. Terrain curvature was also shown to be an important variable, but to a lesser extent at the scale of interest.

  20. Effects of baryons on the statistical properties of large scale structure of the Universe

    Observations of weak gravitational lensing will provide strong constraints on the cosmic expansion history and the growth rate of large scale structure, yielding clues to the properties and nature of dark energy. Their interpretation is impacted by baryonic physics, which are expected to modify the total matter distribution at small scales. My work has focused on determining and modeling the impact of baryons on the statistics of the large scale matter distribution in the Universe. Using numerical simulations, I have extracted the effect of baryons on the power spectrum, variance and skewness of the total density field as predicted by these simulations. I have shown that a model based on the halo model construction, featuring a concentrated central component to account for cool condensed baryons, is able to reproduce accurately, and down to very small scales, the measured amplifications of both the variance and skewness of the density field. Because of well-known issues with baryons in current cosmological simulations, I have extended the central component model to rely on as many observation-based ingredients as possible. As an application, I have studied the effect of baryons on the predictions of the upcoming Euclid weak lensing survey. During the course of this work, I have also worked at developing and extending the RAMSES code, in particular by developing a parallel self-gravity solver, which offers significant performance gains, in particular for the simulation of some astrophysical setups such as isolated galaxy or cluster simulations. (author)

  1. Scaling behavior and morphological properties of the interfaces obtained by the multilayer deposition process

    The aim of the present work was to study numerically the scaling behavior and the morphological properties of the interfaces generated by the multilayer deposition process. We have noticed that, in the case where the ratio of the surface diffusion coefficient to the deposition rate reaches high values D/F > > 1, the interface consists of mound structures. By using the dynamic scaling, we have shown that the height–height correlation function scales with time t and length l as G(l,t) ∼ lαf(t/lα/β) with β = 0.25 ± 0.05 and α = 0.51 ± 0.02. These exponent values are equal to the ones predicted by the Edwards–Wilkinson approach. Besides, our results are in agreement with the growth system of Cu/Cu(100) at 300 K which has been characterized in more detail by a combined scanning tunneling microscopy and spot profile analysis — low energy electronic diffusion study. Moreover, by considering two different methods, we have examined the fractal aspect of the obtained interfaces. - Highlights: • The adlayer interfaces present mound morphologies. • The adlayer interfaces scale with the Family–Vicsek law. • The critical exponents (α, β) are in agreement with those of Edwards–Wilkinson approach

  2. Scaling Behavior and Magnetic Properties for SmxCo5 Films

    2006-01-01

    SmxCo5 (x=1.3, 0.7, 0.4) thin films were prepared by magnetron co-sputtering technique. The samples were annealed at 723 K under Ar atmosphere. The annealed time was chosen as 30 min. The hysteresis loops of the samples were measured under the ac applied magnetic field with the period Tp (2π/ω), H(t)=H0sin(ωt), by vibrating sample magnetometer (VSM). The experimental results indicate that, (1) the average hysteresis loop areas as functions of the values of H0 and ω display a power scaling law with the exponents, A=A0+H0αωβ; (2) the x composition of SmxCo5 film has evident effect on the scaling behavior and magnetic properties; (3) the anisotropy scaling exponents exist clearly in the anisotropy SmxCo5 thin films. Moreover, the scaling behavior of the anisotropy magnetic film was also simulated with Monte Carlo method. The simulated results are consistent with the experimental fact.

  3. Psychometric properties of the Family Resilience Assessment Scale: A Singaporean perspective.

    Chew, Judith; Haase, Anne M

    2016-08-01

    Families of young people with chronic illnesses are more likely to experience higher levels of stress. In turn, their ability to cope with multiple demands is likely to affect young people's adaptation. The purpose of this study was to examine psychometric properties of the Family Resilience Assessment Scale (FRAS), an assessment tool that measures the construct of family resilience. A total of 152 young people with epilepsy, aged 13 to 16years old, from KK Women's and Children's Hospital, Singapore, completed the FRAS along with the Rosenberg Self-Esteem Scale. Factor structure of the FRAS was examined. Exploratory factor analysis resulted in a 7-factor solution - meaning-making and positive outlook, transcendence and spirituality, flexibility and connectedness, social and economic resources (community), social and economic resources (neighbors), clarity and open emotional expression, and collaborative problem-solving - accounting for 83.0% of the variance. Internal consistency of the scale was high (α=0.92). Family resilience was significantly correlated with higher levels of self-esteem. Our study provides preliminary findings that suggest that FRAS is a reliable and valid scale for assessing the construct of family resilience among young people with epilepsy in Singapore. PMID:27337164

  4. Using two scaling exponents to describe the mechanical properties of swollen elastomers

    Okumura, Dai; Kondo, Akifumi; Ohno, Nobutada

    2016-05-01

    We study the ability of two scaling exponents to describe the mechanical properties of swollen elastomers. Swelling effects on the Young's modulus and osmotic pressure of swollen elastomers at equilibrium swelling are investigated using literature data and the Flory-Rehner free energy function. An extended model is developed by introducing two scaling exponents into elastic strain energy functions that are separated into deviatoric and volumetric components. This extended model satisfactorily reproduces the two different swelling effects, and also predicts swelling-induced rupture. The predicted tendency readily explains experimental observations well, i.e., swelling-induced rupture occurs when small extensions are applied in good solvents, and elucidates the mechanism of swelling-induced rupture of elastomers.

  5. Psychometric properties of the Chinese translation of the proactive personality scale.

    Zhou, Le; Shi, Junqi

    2009-08-01

    The purpose of the present study was to examine the psychometric properties of the Chinese translation of the Proactive Personality Scale. Four samples were surveyed. In Sample 1 and Sample 2, exploratory and confirmatory factor analysis results confirmed the unidimensional structure of the 10-item abbreviated version of the scale. In Sample 2, Proactive Personality scores were found to be positively correlated with the personality factors of Extraversion, Conscientiousness, Openness, and Agreeableness, and negatively correlated with Neuroticism. In Sample 3, Proactive Personality was found to be positively related to self-efficacy and political skill. In Sample 4, demographics controlled, Proactive Personality explained significant incremental variance in the employees' self-rated career satisfaction and job performance as rated by immediate supervisors. PMID:19810432

  6. Large-Scale Sunyaev-Zeldovich Effect Measuring Statistical Properties with Multifrequency Maps

    Cooray, A R; Tegmark, M; Cooray, Asantha R.; Hu, Wayne; Tegmark, Max

    2000-01-01

    We study the prospects for extracting detailed statistical properties of theSunyaev-Zel'dovich (SZ) effect associated with large scale structure usingupcoming multifrequency CMB experiments. The greatest obstacle to detecting thelarge-angle signal is the confusion noise provided by the primary anisotropiesthemselves, and to a lesser degree galactic and extragalactic foregrounds. Weemploy multifrequency subtraction techniques and the latest foregrounds modelsto determine the detection threshold for the Boomerang, MAP (several \\muK) andPlanck CMB (sub \\muK) experiments. Calibrating a simplified biased-tracer modelof the gas pressure off recent hydrodynamic simulations, we estimate the SZpower spectrum, skewness and bispectrum through analytic scalings and N-bodysimulations of the dark matter. We show that the Planck satellite should beable to measure the SZ effect with sufficient precision to determine its powerspectrum and higher order correlations, e.g. the skewness and bispectrum.Planck should also be able t...

  7. Psychometric properties of the Mexican version of the Maternal Antenatal Attachment Scale

    Ruth Eunice Castro Mata

    2015-07-01

    Full Text Available Pregnancy is the period for fetal development and growth. In parallel, for the mother is also a complex adaptation time, which in addition to experience physical changes, there is a greater awareness about their child that creates an affectively approach to his or her. The bond between mother and fetus helps to mitigate physical and emotional problems in this stage, preparing them for the future relationship between mother and child attachment. The objective in this study is to evaluate the psychometric properties of the Spanish translation of the MAAS. Reverse translation process was used in order to achieve a conceptual equivalence of the scale. The study included 169 pregnant women attending prenatal care. Exploratory factor analysis indicated two factors with 36.8% of the explained variance, along with 5 items that were removed. The total scale showed a Cronbach’s alpha of 0.694, Quality subscale obtained an alpha of .771 and .550 Preocupation subscale.

  8. Psychometric properties of the Spanish Human System Audit Short-Scale of transformational leadership.

    Berger, Rita; Romeo, Marina; Guardia, Joan; Yepes, Montserrat; Soria, Miguel Angel

    2012-03-01

    The aim of this research is to examine the psychometric properties of a Spanish version of the Human System Audit transformational leadership short-scale (HSA-TFL-ES). It is based on the concept of Bass developed in 1985. The HSA-TFL is a part of the wider Human System Audit frame. We analyzed the HSA-TFL-ES in five different samples with a total number of 1,718 workers at five sectors. Exploratory Factor Analysis corroborated a single factor in all samples that accounted for 66% to 73% of variance. The internal consistency in all samples was good (alpha = .92 - .95). Evidence was found for the convergent validity of the HSA-TFL-ES and the Multifactor Leadership Questionnaire. These results suggested that the HSA-TFL short-scale is a psychometrically sound measure of this construct and can be used for a combined and first overall measurement. PMID:22379726

  9. Constraints on Dark Energy, Observable-mass Scaling Relations, Neutrino Properties and Gravity from Galaxy Clusters

    Rapetti Serra, David Angelo

    Using a data set of 238 cluster detections drawn from the ROSAT All-Sky Survey and X-ray follow-up observations from the Chandra X-ray Observatory and/or ROSAT for 94 of those clusters we obtain tight constraints on dark energy, both luminosity-mass and temperature-mass scaling relations, neutrino...... properties and gravity. I will present the novel statistical framework we employed to self-consistently and simultaneously constrain cosmology and observable-mass scaling relations accounting for survey biases, parameter covariances and systematic uncertainties. Allowing the dark energy equation of state...... and the linear growth index to take any constant values, we find no evidence for departures from the standard cosmological paradigm – General Relativity plus a cosmological constant and cold dark matter. I will review in detail our results and demonstrate the power of X-ray cluster studies to constrain both...

  10. Microstructure and mechanical properties of large-scale ingots of the Zr-1Mo alloy

    A large-scale ingot of Zr-1Mo alloy was produced for industrial manufacturing to investigate whether it is possible to produce an ingot with homogeneity. The homogeneous ingot with a chemical composition of Zr-1 mass%Mo was prepared successfully. The microstructure, mechanical properties, and magnetic susceptibility were evaluated. The microstructure showed a coarse colony structure of a plate-like α phase and a thin β phase. An ω phase precipitation was observed in the β phase. Elongation of 23% and magnetic susceptibility of 12.4 × 10−9 m3 kg−1 (0.98 × 10−6 cm3 g−1) were achieved. We found that it is possible to produce a homogeneous large-scale ingot of Zr-1Mo with high elongation and low magnetic susceptibility. (author)

  11. Scaling of Macroscopic Properties of Porous Sediments Experiencing Compaction: Implications for Geothermal Gradient and Methane Inventory

    Goldobin, Denis S

    2011-01-01

    Porous sediments in geological systems experience stress by the above-laying mass and consequent compaction, which may be significantly nonuniform across the massif. We derive scaling laws for the compaction of sediments of similar geological origin. With these laws, we evaluate the dependence of the transport properties of a fluid-saturated porous medium (permeability, effective molecular diffusivity, hydrodynamic dispersion, and thermal conductivity) on its porosity. In particular, we demonstrate irrelevance of the assumption of a uniform geothermal gradient for systems with nonuniform compaction and importance of the derived scaling laws for mathematical modelling of methane hydrate deposits, which are believed to have potential for impact on global climate change and Glacial-Interglacial cycles.

  12. Psychometric properties of the Thai version of the Diabetes Distress Scale in diabetic seniors

    Thanakwang K

    2014-08-01

    Full Text Available Kattika Thanakwang, Wantana Thinganjana, Roumporn Konggumnerd Institute of Nursing, Suranaree University of Technology, Nakhon Ratchasima, Thailand Background: The Diabetes Distress Scale (DDS is an important measure of diabetes-related emotional distress that has been widely used in the Western world. In Thailand, there is a lack of reliable and valid scales for assessing distress levels in diabetes patients, specifically in older adults.Objectives: The main objectives of this study were to adapt the DDS for use in Thai diabetic elderly and to evaluate its psychometric properties. Methods: The 17-item DDS was linguistically adapted using forward–backward translation and administered to 170 diabetic patients ≥60 years selected from diabetes outpatient clinics of four hospitals in Buriram, Thailand. Statistical analyses included exploratory factor analysis, internal consistency, convergent validity, and test–retest reliability. Results: During factor analysis, a three-factor solution was found to be reasonable for the sub-dimensions of emotional and regimen-related burden (ten items, physician- and nurse-related distress (four items, and diabetes-related interpersonal distress (three items. The Cronbach’s alpha coefficient for the total score was 0.95 and varied between 0.85 and 0.96 in the three subscales. The results provided evidence that supports the convergent validity of the Thai version of the DDS as well as its stability. Conclusion: The Thai version of the DDS has acceptable psychometric properties. It enables assessment of diabetes-specific distress in elderly patients and has the advantage of being easy to use in both clinical and research settings. Keywords: diabetes distress scale, psychometric properties, diabetes-related stress, diabetic elderly

  13. Effect of Nano Scale Fe Doping on Superconducting Properties of MgB2

    S. X. Dou; Soltanian, S.; Zhao, Y.; Getin, E.; Chen, Z.; Horvat, J.

    2004-01-01

    Iron is an important sheath material for fabrication of MgB2 wires. However, the effect of Fe doping on the superconducting properties of MgB2 remains controversial. In this work, we present results of nano-scale Fe particle doping in to MgB2. The Fe doping experiments were performed using both bulk and thin film form. It was found that Fe doping did not affect the lattice parameters of MgB2, as evidenced by the lack of change in the XRD peak positions for MgB2. Because of the high reactivity...

  14. Psychometric Properties of the Spanish Human System Audit Short-Scale of Transformational Leadership

    Berger, Rita; Romeo Delgado, Marina; Guàrdia Olmos, Joan; Yepes i Baldó, Montserrat; Soria Verde, Miguel Ángel

    2012-01-01

    The aim of this research is to examine the psychometric properties of a Spanish version of the Human System Audit transformational leadership short-scale (HSA-TFL-ES). It is based on the concept of Bass developed in 1985. The HSA-TFL is a part of the wider Human System Audit frame. We analyzed the HSA-TFL-ES in five different samples with a total number of 1,718 workers at five sectors. Exploratory Factor Analysis corroborated a single factor in all samples that accounted for 66% to 73% of va...

  15. The MUSIC of galaxy clusters - II. X-ray global properties and scaling relations

    Biffi, V.; Sembolini, F.; De Petris, M.; Valdarnini, R.; Yepes, G.; Gottlöber, S.

    2014-03-01

    We present the X-ray properties and scaling relations of a large sample of clusters extracted from the Marenostrum MUltidark SImulations of galaxy Clusters (MUSIC) data set. We focus on a sub-sample of 179 clusters at redshift z ˜ 0.11, with 3.2 × 1014 h-1 M⊙ MUSIC clusters reasonably resemble the self-similar prediction, especially for correlations involving TX. The observational approach also allows for a more direct comparison with real clusters, from which we find deviations mainly due to the physical description of the ICM, affecting TX and, particularly, LX.

  16. Atomic-Scale Magnetic Properties of Truly 3d-Diluted ZnO

    Mantovan, Roberto; Gunnlaugsson, Haraldur Pall; Johnston, Karl; Masenda, Hilary; Mølholt, Torben Esmann; Naidoo, Deena; Ncube, Mehluli; Shayestehaminzadeh, Seyedmohammad; Bharuth-Ram, Krish; Fanciulli, Marco; Gislason, Haflidi Petur; Langouche, Guido; Olafsson, Sveinn; Pereira, Lino M. C.; Wahl, Ulrich; Torelli, Piero; Weyer, Gerd

    In search for dilute magnetic semiconductors, the magnetic properties at the atomic-scale of Fe atoms incorporated in ZnO, in a concentration range of more than five orders of magnitude from 1 x 10(-5) to 2.2 at% have been probed using emission 57 Fe Mossbauer spectroscopy on implanted Mn-57 and Co...... any signature of magnetic ordering up to 2.2 at%. Despite the many reports of dilute magnetism in 3d-doped ZnO, this atomic level study shows no evidence of any long-range magnetic ordering between isolated Fe atoms incorporated in the ZnO lattice....

  17. Perceived Autonomy in Old Age scale: Factor structure and psychometric properties of the Polish adaptation

    Aleksandra Kroemeke

    2015-01-01

    Objectives Sense of autonomy – the possibility to choose and decide – is one of the markers of positive and active aging. The goal of this study was to examine the Polish adaptation of the Perceived Autonomy in Old Age (PAA) scale and to determine its internal structure and psychometric properties: reliability, as well as construct and discriminant validity. Methods 277 seniors (female=187; male=90), without cognitive function disorders aged 60 to 100 (M=77.4; SD=9.2) took part in t...

  18. Analysis of Carbon Nanotubes on the Mechanical Properties at Atomic Scale

    Xiaowen Lei

    2011-01-01

    Full Text Available This paper aims at developing a mathematic model to characterize the mechanical properties of single-walled carbon nanotubes (SWCNTs. The carbon-carbon (C–C bonds between two adjacent atoms are modeled as Euler beams. According to the relationship of Tersoff-Brenner force theory and potential energy acting on C–C bonds, material constants of beam element are determined at the atomic scale. Based on the elastic deformation energy and mechanical equilibrium of a unit in graphite sheet, simply form ED equations of calculating Young's modulus of armchair and zigzag graphite sheets are derived. Following with the geometrical relationship of SWCNTs in cylindrical coordinates and the structure mechanics approach, Young's modulus and Poisson's ratio of armchair and zigzag SWCNTs are also investigated. The results show that the approach to research mechanical properties of SWCNTs is a concise and valid method. We consider that it will be useful technique to progress on this type of investigation.

  19. Magnetic properties and scale-up of nanostructured cobalt carbide permanent magnetic powders

    Zamanpour, Mehdi, E-mail: zamanpour.m@husky.neu.edu; Bennett, Steven; Taheri, Parisa; Chen, Yajie [Center for Microwave Magnetic Materials and Integrated Circuits, Northeastern University, Boston, Massachusetts 02115 (United States); Harris, Vincent G. [Center for Microwave Magnetic Materials and Integrated Circuits, Northeastern University, Boston, Massachusetts 02115 (United States); Department of Electrical and Computer Engineering, Northeastern University, Boston, Massachusetts 02115 (United States)

    2014-05-07

    Co{sub x}C magnetic nanoparticles were successfully synthesized via a modified polyol process without using a rare-earth catalyst during the synthesis process. The present results show admixtures of Co{sub 2}C and Co{sub 3}C phases possessing magnetization values exceeding 45 emu/g and coercivity values exceeding 2.3 kOe at room temperature. Moreover, these experiments have illuminated the important role of surfactants, reaction temperature, and reaction duration on the crystallographic structure and magnetic properties of Co{sub x}C, while tetraethylene glycol was employed as a reducing agent. The role of the ratios of Co{sub 2}C and Co{sub 3}C phases in the admixture magnetic properties is discussed. The crystallographic structure and particle size of the Co{sub x}C nanoparticles were characterized by X-ray diffractometry and scanning electron microscopy. Vibrating sample magnetometry was used to determine magnetic properties. Scale-up of synthesis to more than 5 g per batch was demonstrated with no significant degradation of magnetic properties.

  20. Effects of Galactic Disc Inclination and Resolution on Observed GMC Properties and Larson's Scaling Relations

    Pan, Hsi-An; Tasker, Elizabeth J; Rosolowsky, Erik; Colombo, Dario; Benincasa, Samantha M; Wadsley, James

    2016-01-01

    With ALMA making it possible to resolve giant molecular clouds (GMCs) in other galaxies, it is becoming necessary to quantify the observational bias on measured GMC properties. Using a hydrodynamical simulation of a barred spiral galaxy, we compared the physical properties of GMCs formed in position-position-position space (PPP) to the observational position-position-velocity space (PPV). We assessed the effect of disc inclination: face-on (PPV_face) and edge-on (PPV_edge), and resolution: 1.5 pc versus 24 pc, on GMC properties and the further implications of using Larson's scaling relations for mass-radius and velocity dispersion-radius. The low-resolution PPV data are generated by simulating ALMA Cycle 3 observations using the CASA package. Results show that the median properties do not differ strongly between PPP and PPV_face under both resolutions, but PPV_edge clouds deviate from these two. The differences become magnified when switching to the lower, but more realistic resolution. The discrepancy can le...

  1. A Brief Scale to Measure Problematic Sexually Explicit Media Consumption: Psychometric Properties of the Compulsive Pornography Consumption (CPC) Scale among Men who have Sex with Men

    Noor, Syed WB; Simon Rosser, B. R.; Erickson, Darin J.

    2014-01-01

    Although the phenomenon of hypersexuality has been described in the literature, and scales of compulsive sexual behavior have been published, the existing measures do not assess compulsive sexually explicit media (SEM) consumption. This study tested the psychometric properties of a new scale, the Compulsive Pornography Consumption (CPC). Exploratory and confirmatory factor analyses results showed good psychometric performance of a five item two factor preoccupation-compulsivity solution. As h...

  2. Commercial Properties, parcel data base attribute, Published in 2006, 1:1200 (1in=100ft) scale, Washoe County.

    NSGIC GIS Inventory (aka Ramona) — This Commercial Properties dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Published Reports/Deeds information as of 2006. It is...

  3. Psychometric properties of a single-item scale to assess sleep quality among individuals with fibromyalgia

    Sadosky Alesia B

    2009-06-01

    Full Text Available Abstract Background Sleep disturbances are a common and bothersome symptom of fibromyalgia (FM. This study reports psychometric properties of a single-item scale to assess sleep quality among individuals with FM. Methods Analyses were based on data from two randomized, double-blind, placebo-controlled trials of pregabalin (studies 1056 and 1077. In a daily diary, patients reported the quality of their sleep on a numeric rating scale ranging from 0 ("best possible sleep" to 10 ("worst possible sleep". Test re-test reliability of the Sleep Quality Scale was evaluated by computing intraclass correlation coefficients. Pearson correlation coefficients were computed between baseline Sleep Quality scores and baseline pain diary and Medical Outcomes Study (MOS Sleep scores. Responsiveness to treatment was evaluated by standardized effect sizes computed as the difference between least squares mean changes in Sleep Quality scores in the pregabalin and placebo groups divided by the standard deviation of Sleep Quality scores across all patients at baseline. Results Studies 1056 and 1077 included 748 and 745 patients, respectively. Most patients were female (study 1056: 94.4%; study 1077: 94.5% and white (study 1056: 90.2%; study 1077: 91.0%. Mean ages were 48.8 years (study 1056 and 50.1 years (study 1077. Test re-test reliability coefficients of the Sleep Quality Scale were 0.91 and 0.90 in the 1056 and 1077 studies, respectively. Pearson correlation coefficients between baseline Sleep Quality scores and baseline pain diary scores were 0.64 (p Conclusion These results provide evidence of the reproducibility, convergent validity, and responsiveness to treatment of the Sleep Quality Scale and provide a foundation for its further use and evaluation in FM patients.

  4. Short scales to assess cannabis-related problems: a review of psychometric properties

    Klempova Danica

    2008-12-01

    Full Text Available Abstract Aims The purpose of this paper is to summarize the psychometric properties of four short screening scales to assess problematic forms of cannabis use: Severity of Dependence Scale (SDS, Cannabis Use Disorders Identification Test (CUDIT, Cannabis Abuse Screening Test (CAST and Problematic Use of Marijuana (PUM. Methods A systematic computer-based literature search was conducted within the databases of PubMed, PsychINFO and Addiction Abstracts. A total of 12 publications reporting measures of reliability or validity were identified: 8 concerning SDS, 2 concerning CUDIT and one concerning CAST and PUM. Studies spanned adult and adolescent samples from general and specific user populations in a number of countries worldwide. Results All screening scales tended to have moderate to high internal consistency (Cronbach's α ranging from .72 to .92. Test-retest reliability and item total correlation have been reported for SDS with acceptable results. Results of validation studies varied depending on study population and standards used for validity assessment, but generally sensitivity, specificity and predictive power are satisfactory. Standard diagnostic cut-off points that can be generalized to different populations do not exist for any scale. Conclusion Short screening scales to assess dependence and other problems related to the use of cannabis seem to be a time and cost saving opportunity to estimate overall prevalences of cannabis-related negative consequences and to identify at-risk persons prior to using more extensive diagnostic instruments. Nevertheless, further research is needed to assess the performance of the tests in different populations and in comparison to broader criteria of cannabis-related problems other than dependence.

  5. Point contact tunneling spectroscopy apparatus for large scale mapping of surface superconducting properties

    Groll, Nickolas; Pellin, Michael J.; Zasadzinksi, John F.; Proslier, Thomas

    2015-09-01

    We describe the design and testing of a point contact tunneling spectroscopy device that can measure material surface superconducting properties (i.e., the superconducting gap Δ and the critical temperature TC) and density of states over large surface areas with size up to mm2. The tip lateral (X,Y) motion, mounted on a (X,Y,Z) piezo-stage, was calibrated on a patterned substrate consisting of Nb lines sputtered on a gold film using both normal (Al) and superconducting (PbSn) tips at 1.5 K. The tip vertical (Z) motion control enables some adjustment of the tip-sample junction resistance that can be measured over 7 orders of magnitudes from a quasi-ohmic regime (few hundred Ω) to the tunnel regime (from tens of kΩ up to few GΩ). The low noise electronic and LabVIEW program interface are also presented. The point contact regime and the large-scale motion capabilities are of particular interest for mapping and testing the superconducting properties of macroscopic scale superconductor-based devices.

  6. Point contact tunneling spectroscopy apparatus for large scale mapping of surface superconducting properties

    We describe the design and testing of a point contact tunneling spectroscopy device that can measure material surface superconducting properties (i.e., the superconducting gap Δ and the critical temperature TC) and density of states over large surface areas with size up to mm2. The tip lateral (X,Y) motion, mounted on a (X,Y,Z) piezo-stage, was calibrated on a patterned substrate consisting of Nb lines sputtered on a gold film using both normal (Al) and superconducting (PbSn) tips at 1.5 K. The tip vertical (Z) motion control enables some adjustment of the tip-sample junction resistance that can be measured over 7 orders of magnitudes from a quasi-ohmic regime (few hundred Ω) to the tunnel regime (from tens of kΩ up to few GΩ). The low noise electronic and LabVIEW program interface are also presented. The point contact regime and the large-scale motion capabilities are of particular interest for mapping and testing the superconducting properties of macroscopic scale superconductor-based devices

  7. Rural to urban population density scaling of crime and property transactions in English and Welsh Parliamentary Constituencies

    Hanley, Quentin S; Ribeiro, Haroldo V

    2016-01-01

    Urban population scaling of resource use, creativity metrics, and human behaviors has been widely studied. These studies have not looked in detail at the full range of human environments which represent a continuum from the most rural to heavily urban. We examined monthly police crime reports and property transaction values across all 573 Parliamentary Constituencies in England and Wales, finding that scaling models based on population density provided a far superior framework to traditional population scaling. We found four types of scaling: i) non-urban scaling in which a single power law explained the relationship between the metrics and population density from the most rural to heavily urban environments, ii) accelerated scaling in which high population density was associated with an increase in the power-law exponent, iii) inhibited scaling where the urban environment resulted in a reduction in the power-law exponent but remained positive, and iv) collapsed scaling where transition to the high density en...

  8. Psychometric Properties of the Intolerance of Uncertainty Scale (IUS in a Lithuanian-speaking population

    Augustinas Rotomskis

    2014-03-01

    Full Text Available Research suggests that intolerance of uncertainty may be important in understanding worry and may play a key role in the etiology and maintenance of worry. Intolerance of uncertainty is measured using the Intolerance of Uncertainty Scale (IUS, which has been shown to be reliable and valid in many studies. The aim of the present study was to develop a Lithuanian version of this instrument. 228 university students completed the scale. The Lithuanian version of the IUS was found to have good psychometric properties. The IUS showed high internal consistency and good test-retest reliability over a five-week period, and good convergent and divergent validity when assessed with measures of trait anxiety, situational anxiety, and depression. Factor analysis indicated that the IUS has a two-factor structure that represents the beliefs that “uncertainty about the future is unfair” and that “uncertainty has negative behavioral and self-referent implications”. In conclusion, it was found that the Lithuanian version of the IUS is a sound scale for assessing intolerance of uncertainty. 

  9. Seeking Observable Imprints of Small-Scale Structure on the Properties of Dark Matter Haloes

    Power, Chris

    2013-01-01

    The characteristic prediction of the Cold Dark Matter (CDM) model of cosmological structure formation is that the Universe should contain a wealth of small-scale structure -- low-mass dark matter haloes and subhaloes. However, galaxy formation is inefficient in their shallow potential wells and so we expect these low-mass haloes and subhaloes to be dark. Can we tell the difference between a Universe in which low-mass haloes are present but dark and one in which they never formed, thereby providing a robust test of the CDM model? We address this question using cosmological simulations to examine how properties of low-mass haloes that are potentially accessible to observation, such as their spatial clustering, rate of accretions and mergers onto massive galaxies and the angular momentum content of massive galaxies, differ between a LCDM model and dark matter models in which low-mass halo formation is suppressed. Adopting an effective cut-off mass scale M_cut below which small-scale power is suppressed in the in...

  10. Psychometric Properties of the Intolerance of Uncertainty Scale (IUS in a Lithuanian-speaking population

    Augustinas Rotomskis

    2014-03-01

    Full Text Available Research suggests that intolerance of uncertainty may be important in understanding worry and may play a key role in the etiology and maintenance of worry. Intolerance of uncertainty is measured using the Intolerance of Uncertainty Scale (IUS, which has been shown to be reliable and valid in many studies. The aim of the present study was to develop a Lithuanian version of this instrument. 228 university students completed the scale. The Lithuanian version of the IUS was found to have good psychometric properties. The IUS showed high internal consistency and good test-retest reliability over a five-week period, and good convergent and divergent validity when assessed with measures of trait anxiety, situational anxiety, and depression. Factor analysis indicated that the IUS has a two-factor structure that represents the beliefs that “uncertainty about the future is unfair” and that “uncertainty has negative behavioral and self-referent implications”. In conclusion, it was found that the Lithuanian version of the IUS is a sound scale for assessing intolerance of uncertainty.

  11. Cold gas properties of the Herschel Reference Survey. II. Molecular and total gas scaling relations

    Boselli, A; Boquien, M; Boissier, S; Catinella, B; Lagos, C; Saintonge, A

    2014-01-01

    We study the properties of the cold gas component of the interstellar medium of the Herschel Reference Survey, a complete volume-limited (15 10^10 Mo) from the COLD GASS survey down to stellar masses M* ~ 10^9 Mo. As scaling variables we use M*, the stellar surface density mu*, the specific star formation rate SSFR, and the metallicity of the target galaxies. By comparing molecular gas masses determined using a constant or a luminosity dependent conversion factor, we estimate the robustness of these scaling relations on the very uncertain assumptions used to transform CO line intensities into molecular gas masses. The molecular gas distribution of a K-band-selected sample is different from that of a far-infrared-selected sample since it includes a significantly smaller number of objects with M(H2) < 6 10^9 Mo. In spiral galaxies the molecular gas phase is only 25-30% of the atomic gas. The analysis also indicates that the slope of the main scaling relations depends on the adopted conversion factor. Among t...

  12. Scaling Properties of a Complete X-ray Selected Galaxy Group Sample

    Lovisari, Lorenzo; Schellenberger, Gerrit

    2014-01-01

    Upcoming X-ray surveys like eROSITA require precise calibration between X-ray observables and mass down to the low mass regime to set tight constraints on the fundamental cosmological parameters. Since an individual mass measurement is only possible for a relatively small number of objects it is crucial to have robust and well understood scaling relations that relate the total mass to easily observable quantities. The main goal of this work is to constrain the galaxy group scaling relations corrected for selection effects, and to quantify the influence of non-gravitational physics at the low-mass regime. We analyzed XMM-Newton observations for a complete sample of galaxy groups selected from the ROSAT All-Sky Survey and we compared the derived scaling properties with a galaxy cluster sample. To investigate the role played by the different non-gravitational processes we then compared the observational data with the predictions of hydrodynamical simulations. After applying the correction for selection effects (...

  13. Psychometric Properties of the Pediatric Emotional Distress Scale in a Diverse Sample of Children Exposed to Interpersonal Violence

    Spilsbury, James C.; Drotar, Dennis; Burant, Christopher; Flannery, Daniel; Creeden, Rosemary; Friedman, Steve

    2005-01-01

    This study determined psychometric properties of the Pediatric Emotional Distress Scale (PEDS) with an ethnically diverse sample of 383 children 2 to 7 years of age exposed to interpersonal violence and participating in a community-based intervention. Means and alpha coefficients for the total scale and 3 subscales fell within previously reported…

  14. Testing the suitability of geologic frameworks for extrapolating hydraulic properties across regional scales

    Mirus, Benjamin B.; Halford, Keith; Sweetkind, Don; Fenelon, Joe

    2016-02-01

    The suitability of geologic frameworks for extrapolating hydraulic conductivity (K) to length scales commensurate with hydraulic data is difficult to assess. A novel method is presented for evaluating assumed relations between K and geologic interpretations for regional-scale groundwater modeling. The approach relies on simultaneous interpretation of multiple aquifer tests using alternative geologic frameworks of variable complexity, where each framework is incorporated as prior information that assumes homogeneous K within each model unit. This approach is tested at Pahute Mesa within the Nevada National Security Site (USA), where observed drawdowns from eight aquifer tests in complex, highly faulted volcanic rocks provide the necessary hydraulic constraints. The investigated volume encompasses 40 mi3 (167 km3) where drawdowns traversed major fault structures and were detected more than 2 mi (3.2 km) from pumping wells. Complexity of the five frameworks assessed ranges from an undifferentiated mass of rock with a single unit to 14 distinct geologic units. Results show that only four geologic units can be justified as hydraulically unique for this location. The approach qualitatively evaluates the consistency of hydraulic property estimates within extents of investigation and effects of geologic frameworks on extrapolation. Distributions of transmissivity are similar within the investigated extents irrespective of the geologic framework. In contrast, the extrapolation of hydraulic properties beyond the volume investigated with interfering aquifer tests is strongly affected by the complexity of a given framework. Testing at Pahute Mesa illustrates how this method can be employed to determine the appropriate level of geologic complexity for large-scale groundwater modeling.

  15. Spatial structure of soil properties at different scales of Mt. Kilimanjaro, Tanzania

    Kühnel, Anna; Huwe, Bernd

    2013-04-01

    Soils of tropical mountain ecosystems provide important ecosystem services like water and carbon storage, water filtration and erosion control. As these ecosystems are threatened by global warming and the conversion of natural to human-modified landscapes, it is important to understand the implications of these changes. Within the DFG Research Unit "Kilimanjaro ecosystems under global change: Linking biodiversity, biotic interactions and biogeochemical ecosystem processes", we study the spatial heterogeneity of soils and the available water capacity for different land use systems. In the savannah zone of Mt. Kilimanjaro, maize fields are compared to natural savannah ecosystems. In the lower montane forest zone, coffee plantations, traditional home gardens, grasslands and natural forests are studied. We characterize the soils with respect to soil hydrology, emphasizing on the spatial variability of soil texture and bulk density at different scales. Furthermore soil organic carbon and nitrogen, cation exchange capacity and the pH-value are measured. Vis/Nir-Spectroscopy is used to detect small scale physical and chemical heterogeneity within soil profiles, as well as to get information of soil properties on a larger scale. We aim to build a spectral database for these soil properties for the Kilimanjaro region in order to get rapid information for geostatistical analysis. Partial least square regression with leave one out cross validation is used for model calibration. Results for silt and clay content, as well as carbon and nitrogen content are promising, with adjusted R² ranging from 0.70 for silt to 0.86 for nitrogen. Furthermore models for other nutrients, cation exchange capacity and available water capacity will be calibrated. We compare heterogeneity within and across the different ecosystems and state that spatial structure characteristics and complexity patterns in soil parameters can be quantitatively related to biodiversity and functional diversity

  16. Testing the suitability of geologic frameworks for extrapolating hydraulic properties across regional scales

    Mirus, Benjamin B.; Halford, Keith; Sweetkind, Don; Fenelon, Joe

    2016-08-01

    The suitability of geologic frameworks for extrapolating hydraulic conductivity ( K) to length scales commensurate with hydraulic data is difficult to assess. A novel method is presented for evaluating assumed relations between K and geologic interpretations for regional-scale groundwater modeling. The approach relies on simultaneous interpretation of multiple aquifer tests using alternative geologic frameworks of variable complexity, where each framework is incorporated as prior information that assumes homogeneous K within each model unit. This approach is tested at Pahute Mesa within the Nevada National Security Site (USA), where observed drawdowns from eight aquifer tests in complex, highly faulted volcanic rocks provide the necessary hydraulic constraints. The investigated volume encompasses 40 mi3 (167 km3) where drawdowns traversed major fault structures and were detected more than 2 mi (3.2 km) from pumping wells. Complexity of the five frameworks assessed ranges from an undifferentiated mass of rock with a single unit to 14 distinct geologic units. Results show that only four geologic units can be justified as hydraulically unique for this location. The approach qualitatively evaluates the consistency of hydraulic property estimates within extents of investigation and effects of geologic frameworks on extrapolation. Distributions of transmissivity are similar within the investigated extents irrespective of the geologic framework. In contrast, the extrapolation of hydraulic properties beyond the volume investigated with interfering aquifer tests is strongly affected by the complexity of a given framework. Testing at Pahute Mesa illustrates how this method can be employed to determine the appropriate level of geologic complexity for large-scale groundwater modeling.

  17. Scaling properties in the adsorption of ionic polymeric surfactants on generic nanoparticles of metallic oxides by mesoscopic simulation

    Mayoral, E

    2014-01-01

    We study the scaling of adsorption isotherms of polyacrylic dispersants on generic surfaces of metallic oxides $XnOm$ as a function of the number of monomeric units, using Electrostatic Dissipative Particle Dynamics simulations. The simulations show how the scaling properties in these systems emerge and how the isotherms rescale to a universal curve, reproducing reported experimental results. The critical exponent for these systems is also obtained, in perfect agreement with the scaling theory of deGennes. Some important applications are mentioned.

  18. Psychometric Properties of the Patient Self-Advocacy Scale: The Persian Version

    Shaghayegh Vahdat

    2015-07-01

    Full Text Available Background: Advances in science and technology and the changes in lifestyle have changed the concept of health in terms of etiology and mortality. The aim of this study was to test the psychometric properties of the original Patient Self-Advocacy Scale for use with an Iranian population. Methods: In the current study, 50 chronic patients between the ages of 25 and 75 were selected as samples. This study was conducted in May 2013 at Bou Ali Sina Hospital in Sari. The translation process and cultural adaptation of the Patient Self-Advocacy Scale were conducted. The face validity and content validity of the instrument were formally verified by analyzing the feedback of patients and health professionals. In order to evaluate questionnaire’s reliability, the intraclass correlation coefficient (ICC was calculated for each item and each domain; and the Cronbach’s alpha was calculated for the entire instruments and each domain. Results: Of the 50 patients participating in the study, 36% were male and 64% were female. The mean age of the patients was 42.5. To comply with the Iranian culture and the study target population, slight changes were applied to the process of translation and validation. In the present study, intraclass correlation coefficient for each item was 0.8-1, which demonstrates excellent reliability of the questionnaire. The Cronbach’s alpha value was 0.75 for overall scale. Conclusion: The Persian version of Patient Self-Advocacy Scale was valid and reliable. Hence, it can be used by public health researchers and health system policy makers for programming and offering patient-oriented health services based on patients’ comments, needs, and preferences.

  19. Psychometric properties of the Danish versions of headache-specific locus of control scale and headache management self-efficacy scale

    Hansen, Jacob Sander; Bendtsen, Lars; Jensen, Rigmor

    2009-01-01

    The purpose of the study is to test the cross-cultural adaptation and psychometric properties of a Danish version of the Headache-Specific Locus of Control Scale (HSLC) and the Headache Management Self-Efficacy Scale (HMSE) in a tertiary headache centre. HSLC and HMSE are headache-specific measures...... with other self-report measures concerning general distress, anxiety, depression, and health-related quality of life. Internal stability of the HSLC subscales and the HMSE were analysed using Chronbach's alpha coefficient. The psychometric properties of the Danish version of the HSLC and the HMSE were....... The results are consistent with the earlier findings of the original American versions of HMSE and HSLC. These scales seem to be valid and valuable tools for testing of psychological aspects related to level of functioning and quality of life for headache patients across different cultures of Western...

  20. Measurement Properties of the Lower Extremity Functional Scale: A Systematic Review.

    Mehta, Saurabh P; Fulton, Allison; Quach, Cedric; Thistle, Megan; Toledo, Cesar; Evans, Neil A

    2016-03-01

    Study Design Systematic review of measurement properties. Background Many primary studies have examined the measurement properties, such as reliability, validity, and sensitivity to change, of the Lower Extremity Functional Scale (LEFS) in different clinical populations. A systematic review summarizing these properties for the LEFS may provide an important resource. Objective To locate and synthesize evidence on the measurement properties of the LEFS and to discuss the clinical implications of the evidence. Methods A literature search was conducted in 4 databases (PubMed, MEDLINE, Embase, and CINAHL), using predefined search terms. Two reviewers performed a critical appraisal of the included studies using a standardized assessment form. Results A total of 27 studies were included in the review, of which 18 achieved a very good to excellent methodological quality level. The LEFS scores demonstrated excellent test-retest reliability (intraclass correlation coefficients ranging between 0.85 and 0.99) and demonstrated the expected relationships with measures assessing similar constructs (Pearson correlation coefficient values of greater than 0.7). The responsiveness of the LEFS scores was excellent, as suggested by consistently high effect sizes (greater than 0.8) in patients with different lower extremity conditions. Minimal detectable change at the 90% confidence level (MDC90) for the LEFS scores varied between 8.1 and 15.3 across different reassessment intervals in a wide range of patient populations. The pooled estimate of the MDC90 was 6 points and the minimal clinically important difference was 9 points in patients with lower extremity musculoskeletal conditions, which are indicative of true change and clinically meaningful change, respectively. Conclusion The results of this review support the reliability, validity, and responsiveness of the LEFS scores for assessing functional impairment in a wide array of patient groups with lower extremity musculoskeletal

  1. Visualization of micro-scale phase displacement processes in retention and outflow experiments: Non-uniqueness of unsaturated flow properties

    MORTENSEN,ANNETTE P.; GLASS JR.,ROBERT J.; HOLLENBECK,KARL; JENSEN,KARSTEN H.

    2000-03-09

    Methods to determine unsaturated hydraulic properties can exhibit random and non-unique behavior. The authors assess the causes for these behaviors by visualizing micro-scale phase displacement processes during equilibrium retention and transient outflow experiments. They observe that the drainage process is composed of a fast fingering followed by a slower backfilling. The influence of each these processes is controlled by the size and the speed of the applied boundary step, the initial saturation and its structure and by small-scale heterogeneities. Because the mixture of these micro-scale processes yields macro-scale effective behavior, measured unsaturated flow properties are also a function of these controls. These results suggest limitations on the current definitions and uniqueness of unsaturated hydraulic properties.

  2. Dynamic scaling and optical properties of Zn(S, O,OH) thin film grown by chemical bath deposition

    Zhang Yi; Li Bo-Yan; Dang Xiang-Yu; Wu Li; Jin Jing; Li Feng-Yan; Ao Jian-Ping; Sun Yun

    2011-01-01

    The scaling behavior and optical properties of Zn(S,O and OH) thin films deposited on soda-lime glass substrates by chemical bath deposition method were studied by combined roughness measurements,scanning electron microscopy and optical properties measurement.From the scaling behaviour,the value of growth scaling exponent β,0.38±0.06,was determined.This value indicated that the Zn(S,O,OH) film growth in the heterogeneous process was influenced by the surface diffusion and shadowing effect.Results of the optical properties measurements disclosed that the transmittance of the film was in the region of 70%-88% and the optical properties of the film grown for 40 min were better than those grown under other conditions.The energy band gap of the film deposited with 40 min was around 3.63 eV.

  3. Correlation between surface properties and wettability of multi-scale structured biocompatible surfaces

    Gorodzha, S. N.; Surmeneva, M. A.; Prymak, O.; Wittmar, A.; Ulbricht, M.; Epple, M.; Teresov, A.; Koval, N.; Surmenev, R. A.

    2015-11-01

    The influence of surface properties of radio-frequency (RF) magnetron deposited hydroxyapatite (HA) and Si-containing HA coatings on wettability was studied. The composition and morphology of the coatings fabricated on titanium (Ti) were characterized using atomic force microscopy (AFM) and X-ray diffraction (XRD). The surface wettability was studied using contact angle analysis. Different geometric parameters of acid-etched (AE) and pulse electron beam (PEB)-treated Ti substrates and silicate content in the HA films resulted in the different morphology of the coatings at micro- and nano- length scales. Water contact angles for the HA coated Ti samples were evaluated as a combined effect of micro roughness of the substrate and nano-roughness of the HA films resulting in higher water contact angles compared with acid-etched (AE) or pulse electron beam (PEB) treated Ti substrates.

  4. Fabrication and characterization of multi-scale microlens arrays with anti-reflection and diffusion properties

    Chen, Yung-Pin; Lee, Chih-Hsien; Wang, Lon A, E-mail: lon@ntu.edu.tw [Photonics and Nano-Structure Laboratory, Department of Electrical Engineering and Graduate Institute of Photonics and Optoelectronics, National Taiwan University, Taipei 10617, Taiwan (China)

    2011-05-27

    In this paper, an effective method for fabricating artificial compound-eye structures is demonstrated. The fabrication of high fill factor microlens arrays (MLAs) with sub-wavelength structures (SWSs) on a polycarbonate (PC) substrate involves nanoimprint and thermo-extrusion techniques by using two different scales of nano/micromolds. In addition, the MLAs with SWSs on the PC substrate would be replicated on a polymethylmethacrylate (PMMA) millimeter concave surface by hot-embossing, forming three-level compound-eye structures. The optical properties of these samples are characterized. The transmittances of two-level PC and three-level PMMA compound structures are increased by 2.5% and 2%, and the uniformities are enhanced by 18% and 24%, respectively.

  5. Psychometric properties of the Hebrew version of the Dutch Work Addiction Scale (DUWAS-10).

    Littman-Ovadia, Hadassah; Balducci, Cristian; Ben-Moshe, Tali

    2014-01-01

    The present study examined the psychometric properties of the Hebrew version of the Dutch Work Addiction Scale (DUWAS-10), developed by Schaufeli, Shimazu, and Taris (2009). Three hundred fifty-one employees completed a questionnaire measuring workaholism; of these, 251 employees completed questionnaires measuring work engagement, job satisfaction, overcommitment, and burnout. The results confirmed the expected two-factor structure of workaholism: working excessively and working compulsively. Strong correlations were obtained between self-reports and peer-reports, and satisfactory correlations were obtained between the first and second administrations of the DUWAS-10. Furthermore, DUWAS-10 scores showed predictable relations with actual number of hours worked per week, work engagement, job satisfaction, overcommitment, and burnout. Interestingly, despite working fewer hours per week, women reported higher levels of workaholism in comparison to men, and managers reported higher levels of workaholism in comparison to nonmanagerial employees. PMID:24839730

  6. Polish Version of the Managing the Emotions of Others Scale (MEOS): Psychometric Properties and Validation.

    Jankowski, Konrad S; Zajenkowski, Marcin; Stolarski, Maciej; Styła, Rafał; Zajenkowska, Anna; Jędrasik-Styła, Małgorzata; Linke, Magdalena

    2016-04-01

    The present study aimed to test the psychometric properties of the Polish version of the managing the emotions of others scale (MEOS). MEOS consists of six dimensions: mood enhancing (Enhance), mood worsening (Worsen), concealing emotions from others (Conceal), use of inauthentic displays for self-serving purposes (Inauthentic), poor emotion skills (Poor skills), and use of diversion to enhance another's mood (Divert). The results showed that among MEOS dimensions, Enhance was the most strongly related to performance-based emotional intelligence. Among the Dark Triad, Narcissism was related to the greatest number of MEOS subscales-all except Poor skills. The results indicated that the MEOS has a similar factor structure, reliability, and pattern of correlations with personality and emotional intelligence in Poland as in previous studies. PMID:27154378

  7. Isolation of nano-meso scale detergent resistant membrane that has properties expected of lipid 'rafts'.

    Morris, Roger J; Jen, Angela; Warley, Alice

    2011-03-01

    This review assesses problems that confound attempts to isolate 'raft' domains from cell membranes, focusing in particular upon the isolation of detergent resistant membrane (DRM). Despite its widespread use, this technique is rightly viewed with skepticism by many membrane biochemists and biophysics for reasons that include the inability to isolate DRMs at 37°C, the temperature at which their lipids are supposed to be ordered and so exclude detergents. If solubilization is done in an ionic buffer that preserves the lamellar phase of the metastable inner leaflet lipids, DRMs can readily be isolated at 37°C, and these have many properties expected of lipid rafts. However, to date these DRMs have remained somewhat larger than current concepts of rafts. We describe an adaptation of this method that purifies nano-meso scale DRMs, and could be a significant step towards purifying the membrane of individual 'rafts'. PMID:21214574

  8. Effects of Atomic-Scale Structure on the Fracture Properties of Amorphous Carbon - Carbon Nanotube Composites

    Jensen, Benjamin D.; Wise, Kristopher E.; Odegard, Gregory M.

    2015-01-01

    The fracture of carbon materials is a complex process, the understanding of which is critical to the development of next generation high performance materials. While quantum mechanical (QM) calculations are the most accurate way to model fracture, the fracture behavior of many carbon-based composite engineering materials, such as carbon nanotube (CNT) composites, is a multi-scale process that occurs on time and length scales beyond the practical limitations of QM methods. The Reax Force Field (ReaxFF) is capable of predicting mechanical properties involving strong deformation, bond breaking and bond formation in the classical molecular dynamics framework. This has been achieved by adding to the potential energy function a bond-order term that varies continuously with distance. The use of an empirical bond order potential, such as ReaxFF, enables the simulation of failure in molecular systems that are several orders of magnitude larger than would be possible in QM techniques. In this work, the fracture behavior of an amorphous carbon (AC) matrix reinforced with CNTs was modeled using molecular dynamics with the ReaxFF reactive forcefield. Care was taken to select the appropriate simulation parameters, which can be different from those required when using traditional fixed-bond force fields. The effect of CNT arrangement was investigated with three systems: a single-wall nanotube (SWNT) array, a multi-wall nanotube (MWNT) array, and a SWNT bundle system. For each arrangement, covalent bonds are added between the CNTs and AC, with crosslink fractions ranging from 0-25% of the interfacial CNT atoms. The SWNT and MWNT array systems represent ideal cases with evenly spaced CNTs; the SWNT bundle system represents a more realistic case because, in practice, van der Waals interactions lead to the agglomeration of CNTs into bundles. The simulation results will serve as guidance in setting experimental processing conditions to optimize the mechanical properties of CNT

  9. Full-scale computation for all the thermoelectric property parameters of half-Heusler compounds

    Hong, A. J.; Li, L.; He, R.; Gong, J. J.; Yan, Z. B.; Wang, K. F.; Liu, J.-M.; Ren, Z. F.

    2016-03-01

    The thermoelectric performance of materials relies substantially on the band structures that determine the electronic and phononic transports, while the transport behaviors compete and counter-act for the power factor PF and figure-of-merit ZT. These issues make a full-scale computation of the whole set of thermoelectric parameters particularly attractive, while a calculation scheme of the electronic and phononic contributions to thermal conductivity remains yet challenging. In this work, we present a full-scale computation scheme based on the first-principles calculations by choosing a set of doped half-Heusler compounds as examples for illustration. The electronic structure is computed using the WIEN2k code and the carrier relaxation times for electrons and holes are calculated using the Bardeen and Shockley’s deformation potential (DP) theory. The finite-temperature electronic transport is evaluated within the framework of Boltzmann transport theory. In sequence, the density functional perturbation combined with the quasi-harmonic approximation and the Klemens’ equation is implemented for calculating the lattice thermal conductivity of carrier-doped thermoelectric materials such as Ti-doped NbFeSb compounds without losing a generality. The calculated results show good agreement with experimental data. The present methodology represents an effective and powerful approach to calculate the whole set of thermoelectric properties for thermoelectric materials.

  10. Statistical comparison of properties of manufactured sand-to-mortar durability and scaling resistance

    Hudec, P. P. [Windsor Univ., Earth Science Dept., ON (Canada); Agistalis, G. [EGNATIA ODOS A. E. Athens (Greece)

    2000-07-01

    Aggregate and manufactured sand from Paleozoic carbonate rocks in southwestern Ontario were compared to mortars containing the manufactured sand. Mortar tests consisted of drying shrinkage, water absorption and adsorption, linear expansion, thermal expansion and scaling and freeze-thaw loss. The aggregate tests included petrographic analysis, water absorption and adsorption, linear and thermal expansion, insoluble residue content, micro-Deval abrasion loss, freeze-thaw loss and rate of settlement. Comparison and grouping of the properties were done by multivariate statistical techniques. Factor analysis showed that the results could be grouped into durability, porosity, thermal and isothermal expansion factors. Stepwise regression predictive models of mortar resistance to salt scaling were developed from results of simpler test on aggregates. K-cluster analysis allowed the placement of aggregate into established quality categories. The procedure also provided the mean, standard deviation and range of test values of a selected number of tests that make up the quality category. Finally, tree analysis provided the passing limits that can be applied to aggregate tests of any defined group of aggregates. Growth of the database over time will permit the comparison of new sources of aggregates with established sources. 8 refs.

  11. The size distribution, scaling properties and spatial organization of urban clusters: a global and regional perspective

    Fluschnik, Till; Ros, Anselmo García Cantú; Zhou, Bin; Reusser, Dominik E; Kropp, Jürgen P; Rybski, Diego

    2014-01-01

    Human development has far-reaching impacts on the surface of the globe. The transformation of natural land cover occurs in different forms and urban growth is one of the most eminent transformative processes. We analyze global land cover data and extract cities as defined by maximally connected urban clusters. The analysis of the city size distribution for all cities on the globe confirms Zipf's law. Moreover, by investigating the percolation properties of the clustering of urban areas we assess the closeness to criticality for various countries. At the critical thresholds, the urban land cover of the countries undergoes a transition from separated clusters to a gigantic component on the country scale. We study the Zipf-exponents as a function of the closeness to percolation and find a systematic decrease with increasing scale, which could be the reason for deviating exponents reported in literature. Moreover, we investigate the average size of the clusters as a function of the proximity to percolation and fi...

  12. The Radio Properties of Radio-Loud Narrow-Line Seyfert 1 Galaxies on Parsec Scales

    Gu, Minfeng; Komossa, S; Yuan, Weimin; Shen, Zhi-Qiang; Wajima, Kiyoaki; Zhou, Hongyan; Zensus, J A

    2015-01-01

    We present the detection of compact radio structures of fourteen radio-loud narrow line Seyfert 1 (NLS1) galaxies from Very Long Baseline Array observations at 5 GHz, which were performed in 2013. While 50\\% of the sources of our sample show a compact core only, the remaining 50\\% exhibit a core-jet structure. The measured brightness temperatures of the cores range from $10^{8.4}$ to $10^{11.4}$ K with a median value of $10^{10.1}$ K, indicating that the radio emission is from non-thermal jets, and that, likely, most sources are not strongly beamed, then implying a lower jet speed in these radio-loud NLS1 galaxies. In combination with archival data taken at multiple frequencies, we find that seven sources show flat or even inverted radio spectra, while steep spectra are revealed in the remaining seven objects. Although all these sources are very radio-loud with $R > 100$, their jet properties are diverse, in terms of their milli-arcsecond (mas) scale (pc scale) morphology and their overall radio spectral shap...

  13. Weight Bias Internalization Scale: Psychometric properties using alternative weight status classification approaches.

    Lee, Morgan S; Dedrick, Robert F

    2016-06-01

    The Weight Bias Internalization Scale (WBIS) was developed to facilitate systematic investigation of internalized weight bias, but the English version has not undergone confirmatory factor analysis (CFA). Additionally, it is unclear whether the measure can be used when participants are grouped based on self-perceived versus body mass index (BMI)-based weight status. The present study evaluated the WBIS in a sample of 243 male and female undergraduate students who were overweight/obese as classified by self-perception or BMI. After exclusion of Item 1 due to poor item-to-total correlation, Cronbach's alphas were .92 and .94 for the perception-based and BMI-based groupings, respectively. CFAs using the reduced 10-item scale with addition of modifications for correlated errors resulted in acceptable model fit for the one-factor model in both groupings. Findings suggest psychometric properties of the modified WBIS are acceptable and are similar for overweight/obese participants grouped by either perceived weight status or BMI. PMID:26907913

  14. Are the Scaling Properties of Bull and Bear Markets Identical? Evidence from Oil and Gold Markets

    Samet Günay

    2014-10-01

    Full Text Available In this study, the scaling properties of the oil and gold return volatilities have been analyzed in the context of bull and bear periods. In the determination of bull and bear turning points, we used the Modified Bry-Boschan Quarterly (MBBQ algorithm. Results showed that the business cycle phase shapes of the bear periods in the oil market are almost linear, whereas the bull and bear periods of the gold and bull period of the oil market are convex. This means that there are sharper declines in the bear period of the oil market. Following the detection of bull and bear periods, scaling exponent H analysis was performed via the aggregated variance, Higuchi’s statistic, Peng’s statistic, rescaled range, boxed periodogram and wavelet fit models, which are from the time, frequency and wavelet domains. As there are conflicts about the credibility of these methods in the literature, we have used the shuffling procedure in order to determine the most robust methods. According to the results, bear periods have higher volatility persistency than bull periods.

  15. Development and Datametric Properties of a Scale Measuring Students' Perceptions of The Classroom Assessment Environment

    Hussain Alkharusi

    2011-01-01

    Full Text Available Each classroom has its own assessment environment perceived by the students and springs from the teacher's assessment practices. Although students' perceptions of the assessment environment may influence their achievement-related outcomes, little attention has been given to the measurement of perceived classroom assessment environment. This study reports on the development and datametric properties of a scale measuring students' perceptions of the classroom assessment environment. A total of 450 students enrolled in the tenth grade English language classes at Muscat public schools in Oman completed the scale. Results yielded two subscales of the perceived classroom assessment environment: learning-, and performance-oriented environments. The correlations between them suggested that they represented unique aspects of the classroom assessment environment as perceived by the students. Additional validity evidence was obtained through gender differences and correlations of the subscales scores with the total scores received in the subject at end of the semester. Reliability analyses showed that the subscales' scores had relatively moderate levels of internal consistency. Implications and recommendations for classroom instruction and assessment as well as for future research are discussed.

  16. Psychometric properties of the Adolescent Dissociative Experiences Scale in a sample of Italian adolescents.

    Schimmenti, Adriano

    2016-01-01

    The purpose of this study was to examine the psychometric properties of the Italian translation of the Adolescent Dissociative Experiences Scale (A-DES). A sample of 1,806 high-school students between the ages of 13 and 18 years, recruited in 6 Italian cities, completed the A-DES. The A-DES showed high internal consistency, excellent item-to-scale homogeneity, good split-half reliability, and a single-factor structure. The scores of the Italian adolescents were comparable to those found in previous research with the measure. No gender differences were found in mean A-DES scores, but boys and girls showed different patterns of responses on A-DES items. Age differences were also found, with 13- and 18-year-old students scoring higher on the measure than the other participants. A cluster analysis showed that participants could be consistently grouped into 2 clusters of low- and high-dissociative adolescents. This study supports the A-DES as a reliable and valid screening measure for dissociative symptoms in adolescents. PMID:26156626

  17. Psychometric Properties of the Finnish Version of the Resilience Scale and its Short Version

    Heidi Losoi

    2013-03-01

    Full Text Available Aim: To investigate the psychometric properties of the Finnish version of the Resilience Scale (RS and its short version (RS-14, as well as the relationship of resilience with demographic variables and self-perceived health. Method: A standard procedure was used for translation of the scale, and 243 participants (75% women, mean age = 41.0; SD = 17.8 were evaluated with the RS, the RS-14, and the EuroQol 5D. Results: The mean level of resilience was found to be moderate. Both the RS and the RS-14 showed good internal consistency reliability, .90 and .87, respectively. No clear factor structure was found. Both assessments correlated with age but there was no statistically significant association with education or gender. However, a relatively weak but statistically significant correlation between the RS and the RS-14 with self-reported health was found in women. Conclusion: The Finnish versions of the RS and RS-14 can be recommended to be used in clinical and scientific settings. Gender is suggested to be taken into account in further research of resilience.

  18. Full-scale computation for all the thermoelectric property parameters of half-Heusler compounds.

    Hong, A J; Li, L; He, R; Gong, J J; Yan, Z B; Wang, K F; Liu, J-M; Ren, Z F

    2016-01-01

    The thermoelectric performance of materials relies substantially on the band structures that determine the electronic and phononic transports, while the transport behaviors compete and counter-act for the power factor PF and figure-of-merit ZT. These issues make a full-scale computation of the whole set of thermoelectric parameters particularly attractive, while a calculation scheme of the electronic and phononic contributions to thermal conductivity remains yet challenging. In this work, we present a full-scale computation scheme based on the first-principles calculations by choosing a set of doped half-Heusler compounds as examples for illustration. The electronic structure is computed using the WIEN2k code and the carrier relaxation times for electrons and holes are calculated using the Bardeen and Shockley's deformation potential (DP) theory. The finite-temperature electronic transport is evaluated within the framework of Boltzmann transport theory. In sequence, the density functional perturbation combined with the quasi-harmonic approximation and the Klemens' equation is implemented for calculating the lattice thermal conductivity of carrier-doped thermoelectric materials such as Ti-doped NbFeSb compounds without losing a generality. The calculated results show good agreement with experimental data. The present methodology represents an effective and powerful approach to calculate the whole set of thermoelectric properties for thermoelectric materials. PMID:26947395

  19. Scale-dependent analyses of precipitation forecasts and cloud properties using the Dynamic State Index

    Antje Névir Claussnitzer

    2008-12-01

    Full Text Available The objective of this study is a scale-dependent analysis of precipitation forecasts of the German Weather Service's (DWD non-hydrostatic Lokal-Modell (LM, COSMO-DE with regard to dynamical-statistical parameters and cloud properties. We propose a newly designed Dynamic State Index (DSI to evaluate precipitation processes. The DSI is presented in the context of a case study in the synoptic scale and in a statistical approach. The DSI quantitatively describes the deviation from a stationary, adiabatic and reversible solution of the primitive equations. As demonstrated by the example of the winter storm "Kyrill", the analysis of the vertical structure of the DSI gives a relation to the IPV-Thinking, introduced by Hoskins et al. (1985. Furthermore, the DSI-pattern features the characteristic filament-like structure of rainbands with embedded convective cells. In a next step the DSI is not only correlated with modelled precipitation but also with observed precipitation as well as cloud types. The absolute value of the DSI shows moderate correlations with hourly LM and high correlations with hourly COSMO-DE forecast data, based on 24 hour predictions. The statistical analysis of clouds with the index reveals a DSI-threshold, which is used to introduce a novel precipitation activity index of different cloud classes. In conclusion, the results highlight the importance of dynamical processes for the generation of rainfall.

  20. Dimensionality and scale properties of the Edinburgh Depression Scale (EDS in patients with type 2 diabetes mellitus: the DiaDDzoB study

    Pop Victor JM

    2011-08-01

    Full Text Available Abstract Background Depression is a common complication in type 2 diabetes (DM2, affecting 10-30% of patients. Since depression is underrecognized and undertreated, it is important that reliable and validated depression screening tools are available for use in patients with DM2. The Edinburgh Depression Scale (EDS is a widely used method for screening depression. However, there is still debate about the dimensionality of the test. Furthermore, the EDS was originally developed to screen for depression in postpartum women. Empirical evidence that the EDS has comparable measurement properties in both males and females suffering from diabetes is lacking however. Methods In a large sample (N = 1,656 of diabetes patients, we examined: (1 dimensionality; (2 gender-related item bias; and (3 the screening properties of the EDS using factor analysis and item response theory. Results We found evidence that the ten EDS items constitute a scale that is essentially one dimensional and has adequate measurement properties. Three items showed differential item functioning (DIF, two of them showed substantial DIF. However, at the scale level, DIF had no practical impact. Anhedonia (the inability to be able to laugh or enjoy and sleeping problems were the most informative indicators for being able to differentiate between the diagnostic groups of mild and severe depression. Conclusions The EDS constitutes a sound scale for measuring an attribute of general depression. Persons can be reliably measured using the sum score. Screening rules for mild and severe depression are applicable to both males and females.

  1. Impact of large-scale dynamics on the microphysical properties of midlatitude cirrus

    Muhlbauer, Andreas; Ackerman, Thomas P.; Comstock, Jennifer M.; Diskin, G. S.; Evans, Stuart; Lawson, Paul; Marchand, Roger

    2014-04-16

    In situ microphysical observations 3 of mid-latitude cirrus collected during the Department of Energy Small Particles in Cirrus (SPAR-TICUS) field campaign are combined with an atmospheric state classification for the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) site to understand statistical relationships between cirrus microphysics and the large-scale meteorology. The atmospheric state classification is informed about the large-scale meteorology and state of cloudiness at the ARM SGP site by combining ECMWF ERA-Interim reanalysis data with 14 years of continuous observations from the millimeter-wavelength cloud radar. Almost half of the cirrus cloud occurrences in the vicinity of the ARM SGP site during SPARTICUS can be explained by three distinct synoptic condi- tions, namely upper-level ridges, mid-latitude cyclones with frontal systems and subtropical flows. Probability density functions (PDFs) of cirrus micro- physical properties such as particle size distributions (PSDs), ice number con- centrations and ice water content (IWC) are examined and exhibit striking differences among the different synoptic regimes. Generally, narrower PSDs with lower IWC but higher ice number concentrations are found in cirrus sam- pled in upper-level ridges whereas cirrus sampled in subtropical flows, fronts and aged anvils show broader PSDs with considerably lower ice number con- centrations but higher IWC. Despite striking contrasts in the cirrus micro- physics for different large-scale environments, the PDFs of vertical velocity are not different, suggesting that vertical velocity PDFs are a poor predic-tor for explaining the microphysical variability in cirrus. Instead, cirrus mi- crophysical contrasts may be driven by differences in ice supersaturations or aerosols.

  2. Psychometric properties of the Chinese version of the Perceived Stress Scale in policewomen.

    Zhen Wang

    Full Text Available BACKGROUND: The 10-item Perceived Stress Scale (PSS-10 is one of most widely used instruments to measure a global level of perceived stress in a range of clinical and research settings. This study was conducted to examine the psychometric properties of the Simplified Chinese version of the PSS-10 in policewomen. METHODOLOGY: A total of 240 policewomen were recruited in this study. The Simplified Chinese versions of the PSS-10, the Beck Depression Inventory Revised (BDI-II, and the Beck Anxiety Inventory (BAI were administered to all participants, and 36 of the participants were re-tested two weeks after the initial testing. PRINCIPAL FINDINGS: The overall Cronbach's alpha was 0.86, and the test-retest reliability coefficient was 0.68. Exploratory Factor Analysis (EFA yielded 2 factors with eigenvalues of 4.76 and 1.48, accounting for 62.41% of variance. Factor 1 consisted of 6 items representing "negative feelings"; whereas Factor 2 consisted of 4 items representing "positive feelings". The item loadings ranged from 0.72 to 0.83. The Confirmatory factor analysis (CFA indicated a very good fit of this two-factor model to this sample. The PSS-10 significantly correlated with both BDI-II and BAI, indicating an acceptable concurrent validity. CONCLUSIONS: The Simplified Chinese version of the PSS-10 demonstrated adequate psychometric properties for evaluating stress levels. The results support its use among the Chinese population.

  3. A Comparison of Cosmological Codes: Properties of Thermal Gas and Shock Waves in Large Scale Structures

    Vazza, F; Ryu, D; Brunetti, G; Gheller, C; Kang, H; Pfrommer, C

    2011-01-01

    [...]We present results for the statistics of thermal gas and the shock wave properties for a large volume simulated with three different cosmological numerical codes: the Eulerian total variations diminishing code TVD, the Eulerian piecewise parabolic method-based code ENZO, and the Lagrangian smoothed-particle hydrodynamics code GADGET. Starting from a shared set of initial conditions, we present convergence tests for a cosmological volume of side-length 100 Mpc/h, studying in detail the morphological and statistical properties of the thermal gas as a function of mass and spatial resolution in all codes. By applying shock finding methods to each code, we measure the statistics of shock waves and the related cosmic ray acceleration efficiencies, within the sample of simulations and for the results of the different approaches. We discuss the regimes of uncertainties and disagreement among codes, with a particular focus on the results at the scale of galaxy clusters. We report that, even if the bulk of thermal...

  4. Atomic-scale properties of Ni-based FCC ternary, and quaternary alloys

    The aim of this study is to characterize some atomic-scale properties of Ni-based FCC multicomponent alloys. For this purpose, we use Monte Carlo method combined with density functional theory calculations to study short-range order (SRO), atomic displacements, electronic density of states, and magnetic moments in equimolar ternary NiCrCo, and quaternary NiCrCoFe alloys. According to our study, the salient features for the ternary alloy are a negative SRO parameter between Ni–Cr and a positive between Cr–Cr pairs as well as a weakly magnetic state. For the quaternary alloy we predict negative SRO parameter for Ni–Cr and Ni–Fe pairs and positive for Cr–Cr and Fe–Fe pairs. Atomic displacements for both ternary and quaternary alloys are negligible. In contrast to the ternary, the quaternary alloy shows a complex magnetic structure. The electronic structure of the ternary and quaternary alloys shows differences near the Fermi energy between a random solid solution and the predicted structure with SRO. Despite that, the calculated EXAFS spectra does not show enough contrast to discriminate between random and ordered structures. The predicted SRO has an impact on point-defect energetics, electron–phonon coupling and thermodynamic functions and thus, SRO should not be neglected when studying properties of these two alloys

  5. Energy Dependence and Scaling Property of Localization Length near a Gapped Flat Band

    Ge, Li

    2015-01-01

    Using a tight-binding model for a one-dimensional Lieb lattice, we show that the localization length near a gapped flat band behaves differently from the typical Urbach tail in a band gap: instead of reducing monotonically as the energy E moves away from the flat band energy E_{FB}, the presence of the flat band causes a nonmonotonic energy dependence of the localization length. This energy dependence follows a scaling property when the energy is within the spread (W) of uniformly distributed diagonal disorder, i.e. the localization length is only a function of (E-E_{FB})/W. Several other lattices are compared to distinguish the effect of the flat band on the localization length, where we eliminate, shift, or duplicate the flat band, without changing the dispersion relations of other bands. Using the top right element of the Green's matrix, we derive an analytical relation between the density of states and the localization length, which shines light on these properties of the latter, including a summation rul...

  6. Revealing Optical Properties of Reduced-Dimensionality Materials at Relevant Length Scales.

    Ogletree, D Frank; Schuck, P James; Weber-Bargioni, Alexander F; Borys, Nicholas J; Aloni, Shaul; Bao, Wei; Barja, Sara; Lee, Jiye; Melli, Mauro; Munechika, Keiko; Whitelam, Stephan; Wickenburg, Sebastian

    2015-10-14

    Reduced-dimensionality materials for photonic and optoelectronic applications including energy conversion, solid-state lighting, sensing, and information technology are undergoing rapid development. The search for novel materials based on reduced-dimensionality is driven by new physics. Understanding and optimizing material properties requires characterization at the relevant length scale, which is often below the diffraction limit. Three important material systems are chosen for review here, all of which are under investigation at the Molecular Foundry, to illustrate the current state of the art in nanoscale optical characterization: 2D semiconducting transition metal dichalcogenides; 1D semiconducting nanowires; and energy-transfer in assemblies of 0D semiconducting nanocrystals. For each system, the key optical properties, the principal experimental techniques, and important recent results are discussed. Applications and new developments in near-field optical microscopy and spectroscopy, scanning probe microscopy, and cathodoluminescence in the electron microscope are given detailed attention. Work done at the Molecular Foundry is placed in context within the fields under review. A discussion of emerging opportunities and directions for the future closes the review. PMID:26332202

  7. Measurement properties of the Minimal Insomnia Symptom Scale (MISS in an elderly population in Sweden

    Fagerström Cecilia

    2010-11-01

    Full Text Available Abstract Background Insomnia is common among elderly people and associated with poor health. The Minimal Insomnia Symptom Scale (MISS is a three item screening instrument that has been found to be psychometrically sound and capable of identifying insomnia in the general population (20-64 years. However, its measurement properties have not been studied in an elderly population. Our aim was to test the measurement properties of the MISS among people aged 65 + in Sweden, by replicating the original study in an elderly sample. Methods Data from a cross-sectional survey of 548 elderly individuals were analysed in terms of assumptions of summation of items, floor/ceiling effects, reliability and optimal cut-off score by means of ROC-curve analysis and compared with self-reported insomnia criteria. Results Corrected item-total correlations ranged between 0.64-0.70, floor/ceiling effects were 6.6/0.6% and reliability was 0.81. ROC analysis identified the optimal cut-off score as ≥7 (sensitivity, 0.93; specificity, 0.84; positive/negative predictive values, 0.256/0.995. Using this cut-off score, the prevalence of insomnia in the study sample was 21.7% and most frequent among women and the oldest old. Conclusions Data support the measurement properties of the MISS as a possible insomnia screening instrument for elderly persons. This study make evident that the MISS is useful for identifying elderly people with insomnia-like sleep problems. Further studies are needed to assess its usefulness in identifying clinically defined insomnia.

  8. Evaluation of anti-scale property of CrN coatings at high temperature and high pressure

    It is well known that oxide scale which adheres to the inner wall of the nozzle in nuclear power plant causes a serious problem. This study was carried out to obtain the knowledge about initiation and deposition behavior of oxide scale on the surface of SUS304 stainless steel and the evaluation of anti-scale property of chromium nitride (CrN) coatings at high temperature and high pressure. SUS304 stainless steel and CrN coating specimens were heated in water up to 200degC for more than 250 hours. Obtained results are summarized as follows. Initiation of the scale started from corrosive part of SUS304 stainless steel and the scale grows by deposition of magnetite particles. CrN coating can be applied to prevent the initiation and deposition of oxide scale. (author)

  9. Wear properties of H13 with micron scale and nano scale grains bionic units processed by laser remelting

    Zhang, Peng; Zhou, Hong; Wang, Cheng-tao; Liu, Yan; Ren, Lu-quan

    2013-12-01

    By simulating the cuticles of some soil animals, a combination of soft part (untreated substrate) and hard part (laser remelting area) structure was designed on metal surface to get an improved performance. Different specimens were prepared which contained units with micro and nano scale grains. The microstructures were observed by environmental field emission scanning electron microscopy. X-ray diffraction was used to identify the phases. The results of these tests indicate that due to the rapid solidification condition in the water, nano scale grains have a high microhardness between 1300 and 1000 HV. Retained austenite was found in it. Some of them transform to martensite in block on ring wear test. Specimens with bionic unit have a better wear resistance. Especially, the units with nano grains bring a further enhancement. The alternate soft and hard in macroscopic (substrate and laser remelting area) and microscopic (austenite and martensite) structure played a key role in improving the H13 wear resistance.

  10. An investigation into the psychometric properties of the Hospital Anxiety and Depression Scale in patients with breast cancer

    Kendell Kate; Morse Rachel C; Martin Colin R; Rodgers Jacqui; Verrill Mark

    2005-01-01

    Abstract Background To determine the psychometric properties of the Hospital Anxiety and Depression Scale (HADS) in patients with breast cancer and determine the suitability of the instrument for use with this clinical group. Methods A cross-sectional design was used. The study used a pooled data set from three breast cancer clinical groups. The dependent variables were HADS anxiety and depression sub-scale scores. Exploratory and confirmatory factor analyses were conducted on the HADS to det...

  11. Biomat flow: fluorescent dye field experiments, pore-scale modeling of flow and transport properties, and field-scale flow models

    Gerke, K.; Sidle, R. C.; Mallants, D.; Vasilyev, R.; Karsanina, M.; Skvortsova, E. B.; Korost, D. V.

    2013-12-01

    Recent studies highlight the important role that the upper litter layer in forest soils (biomat) plays in hillslope and catchment runoff generation. This biomat layer is a very loose material with high porosity and organic content. Direct sampling is usually problematic due to limited layer thickness. Conventional laboratory measurements can mobilize solids or even cause structure failure of the sample thus making measurements unreliable. It is also difficult to assess local variation in soil properties and transition zones using these methods; thus, they may not be applicable to biomat studies. However, if the physics of flow through this layer needs to be quantified and incorporated into a model, a detailed study of hydraulic properties is necessary. Herein we show the significance of biomat flow by staining experiments in the field, study its structure and transition to mineral soil layer using X-ray micro-tomography, assess hydraulic properties and structure differences using a pore-scale modeling approach, and, finally, use conventional variably-saturated flow modeling based on Richards equation to simulate flow in the hillslope. Using staining tracers we show that biomat flow in forested hillslopes can extend long distances (lateral displacement was about 1.2 times larger than for subsurface lateral flow) before infiltration occurs into deeper layers. The three-dimensional structure of an undisturbed sample (4 x 3 x 2.5 cm) of both biomat and deeper consolidated soil was obtained using an X-ray micro-tomography device with a resolution of 15 um. Local hydraulic properties (e.g., permeability and water retention curve) for numerous layers (e.g., transition zones, biomat, mineral soil) were calculated using Stokes flow FDM solution and pore-network modeling. Anisotropy, structure differences, and property fluctuations of different layers were quantified using local porosity analysis and correlation functions. Current results support the hypothesis that small-scale

  12. Soil magnetic properties in Bulgaria at a national scale-Challenges and benefits

    Jordanova, Neli; Jordanova, Diana; Petrov, Petar

    2016-02-01

    Establishing topsoil magnetic database at a national scale provides important information for soil classification, evaluation of soil drainage, indirect estimation of the total soil carbon and initial planning in precision agriculture. The Bulgarian database consists of 511 topsoil samples from the upper 20 cm of natural unpolluted soils. Samples have been characterized by detailed magnetic measurements, including mass-specific magnetic susceptibility, frequency dependent magnetic susceptibility, anhysteretic remanence, isothermal remanence and their ratios, hysteresis parameters and ratios, as well as soil reaction (pH). Histograms of the measured parameters per soil type and for the whole database show specific peculiarities and dependence from various parameters. Statistical factor analysis revealed that 87% from the total variance can be explained by four factors. The main factor is dominated by the contribution from concentration-dependent magnetic parameters, second one reflects the role of fine-grained pedogenic magnetic fraction, the third one is determined by the properties of the parent material, fourth one is governed by the internal structural peculiarities of the magnetic particles. The results from cluster analysis reveal the role of soil type and geology for the observed magnetic characteristics. The results emphasize the major role of geology (parent material) for the magnetic signature of topsoil samples on a national scale using sampling density of 1 sample/200 km2. Spatial interpolation of different magnetic parameters using modelled experimental variograms and kriging algorithm highlight lateral peculiarities in the concentration and grain size of the strongly magnetic iron oxides in the topsoils. Additional geochemical data for selected set of samples and meteorological information reveal the role of climate characteristics (mean annual temperature and precipitation) on the formation and development of the strongly magnetic pedogenic fraction

  13. Psychometric Properties of the Montgomery-Åsberg Depression Rating Scale in Severely Obese Patients.

    Paiva-Medeiros, Paula Francielle; Duarte-Guerra, Leorides Severo; Santo, Marco Aurélio; Lotufo-Neto, Francisco; Wang, Yuan-Pang

    2015-01-01

    Obesity is a chronic condition worldwide and has frequent association with major depression. The Montgomery-Åsberg Depression Rating Scale (MADRS) was applied to obese patients in order to detect briefly and systematically depressive symptoms. The objectives were: to estimate the reliability of the MADRS and to investigate the criterion validity of MADRS. The best cut-off point to detect depressive symptoms was determined in comparison with the Structured Clinical Interview for DSM-IV Axis I Diagnosis (SCID-I). The sample was recruited consecutively from the waiting list of a bariatric surgery service of the university clinic. Trained clinical psychologists applied the assessment instruments. The final sample was comprised of 374 class III obese adults (women 79.9 %, mean age 43.3 years [SD 11.6], mean body mass index 47.0 kg/m2 [SD 7.1]). The mean total score of the MADRS was 7.73 (SD 11.33) for the total sample, with a Cronbach's alpha coefficient of .93. Women presented higher mean score than men (8.08 versus 6.33; p = .23). The best cut-off point was 13/14 in accordance with the Receiver Operating Characteristics (ROC) curve analysis, yielding a sensitivity of .81 and specificity of .85. The overall ability to discriminate depression according to area under the curve was .87. The results showed that the MADRS is a reliable and valid scale to detect depressive symptoms among patients seeking treatment in preoperative period, displaying adequate psychometric properties. PMID:26364907

  14. Modelling properties and understanding processes across different spatial scales within the critical zone through environmental correlation.

    Wilford, J.; de Caritat, P.

    2015-12-01

    An environmental correlation approach establishes predictive relationships between the measured properties of the critical zone with a comprehensive suite of environmental covariates. The environmental covariates ideally cover or represent proxies for the factors that control soil/regolith formation. These factors include parent material, time, climate, biological and landscape processes. The corresponding proxies include lithology maps, satellite imagery (e.g. Landsat TM, MODIS), geophysical imagery (e.g. magnetics, radiometrics and gravity), terrain attributes (e.g. slope, wetness index) and climate surfaces (e.g. annual rainfall). Using this approach we model and spatially predict two important components of the critical zone including: depth of weathering and geochemistry. Predictive maps of these attributes are based on nested piecewise linear tree models. Models of critical zone thickness and geochemistry (including elements, element ratios and chemical indices) have been developed at the catchment scale and at the continental scale. Thickness and weathering intensity (determined through geochemical weathering indices) of the critical zone profoundly affects groundwater interactions, subsoil water movement, water storage and nutrient availability. In highly weathered Australian landscapes we commonly see geochemical convergence typified by the abundance of end-member weathering phases such as quartz, clays and oxyhydroxides. The modelling can be used to map elements of economic importance or those which are potentially hazardous to human health. Modelling and integration of environmental covariates helps to facilitate our understanding of the processes occurring within the lithosphere, hydrosphere, atmosphere and biosphere that control the nature and distribution of the weathered materials. It also provides an approach to integrate and model the vast amount of spatial information we have from ground, airborne and satellite remote sensing.

  15. Electrical properties and scaling behaviour of Sm3+ doped CaF2-bismuth borate glasses

    A A Ali; M H Shaaban

    2011-06-01

    The electrical properties for 20Bi2O3–60B2O3 (20−)–CaF2–Sm2O3 glasses (0 ≤ ≤ 2) were measured in the temperature range 297 K up to 629 K and in the frequency range 0.1–100 kHz. The d.c. and a.c. conductivity values and the dielectric loss (tan ) values were found to increase with increasing Sm2O3 content, whereas the activation energy of conductivities and the dielectric constant decreased. These results were attributed to the introduction of the rare earth ions; promote the formation of a high number of non-bridging oxygen atoms, which facilitate the mobility of charge carriers. The frequency dependence of the a.c. conductivity follows the power law ac() =As . The frequency exponent () values (0.64 < < 0.8) decrease with increasing temperature. This suggested that the a.c. conduction mechanism follows the correlated barrier hopping model (CBH). The dielectric constant (') and dielectric loss (tan values) were found to increase with increasing temperature and increasing Sm2O3 concentration in the glass. The a.c. conductivities as a function of frequency at different temperatures of a given glass superimposed onto a master curve (Roling scaling model). Furthermore, we have performed to scale the data as a function of composition. Two master curves were obtained, which suggested that there are differences in dominant charge carriers between glasses having Sm2O3 concentration ≥1 and glass of Sm2O3 concentration <1.

  16. A multi-scale point of view on the structure-property relationships of A15 superconductors

    Yanlong Ding; Min Pan; Shuiquan Deng; Yong Zhao

    2014-01-01

    Nb3Sn and other A15 members have been widely applied in nuclear power, nuclear magnetic reso-nance, and high-energy particle accelerators for their high critical current density (Jc) and upper critical field (Bc2). There have been comprehensive and intensive studies on the applications, the fundamental lattice dynamic and electronic properties, etc., of A15 superconductors. Various reviews on the preparations, structures, and properties have already been written in the last few years. Nevertheless, on account of the large amount of existing facts and views, a coherent view on the relations between the structures and properties has not appeared to unify the facts. This article sketches a multi-scale point of view on the relations between the multi-scale structures and the corresponding properties.

  17. Testing the Psychometric Properties of a Chinese Version of the Level of Expressed Emotion Scale

    Wai Tong Chien

    2014-01-01

    Full Text Available This study tested the psychometric properties of a Chinese version of the level of expressed emotion scale in Hong Kong Chinese patients with severe mental illness and their family caregivers. First, the semantic equivalence with the original English version and test-retest reliability at 2-week interval of the Chinese version was examined. After that, the reproducibility, construct validity, and internal consistency of the Chinese version were tested. The Chinese version indicated good semantic equivalence with the English version (kappa values = 0.76–0.95 and ICC = 0.81–0.92, test-retest reliability (r = 0.89–0.95, P<0.01, and internal consistency (Cronbach’s α = 0.86–0.92. Among 262 patients with severe mental illness and their caregivers, the 50-item Chinese version had substantial loadings on one of the four factors identified (intrusiveness/hostility, attitude towards patient, tolerance, and emotional involvement, accounting for 71.8% of the total variance of expressed emotion. In confirmatory factor analysis, the identified four-factor model showed the best fit based on all fit indices (χ2/df = 1.93, P=0.75; AGFI = 0.96; TLI = 1.02; RMSEA = 0.031; WRMR = 0.78 to the collected data. The four-factor Chinese version also indicated a good concurrent validity with significant correlations with family functioning (r = −0.54 and family burden (r = 0.49 and a satisfactory reproducibility over six months (intraclass correlation coefficient of 0.90. The mean scores of the overall and subscale of the Chinese version in patients with unipolar disorder were higher than in other illness groups (schizophrenia, psychotic disorders, and bipolar disorder; P<0.01. The Chinese version demonstrates sound psychometric properties to measure families’ expressed emotion in Chinese patients with severe mental illness, which are found varied across countries.

  18. CHARACTERIZING AND MAPPING THE FIELD SCALE SPATIAL VARIABILITY OF SURFACE HORIZON SOIL PROPERTIES AND WATER CONTENT WITH NONINVASIVE EM38

    Schroeder, Ryan W.R.; Austin, Robert; Heitman, Joshua; Howard, Adam

    2015-01-01

    The spatial variability of physical soil properties at the field scale is increasingly important in agriculture and natural resource management. Changes in topography, parent material, management practices, erosion/deposition rates, etc. can influence the variability of the soil’s physical properties and help guide management and land use plans. The Geonics EM38 is a noninvasive geophysical sensor which is used to measure the apparent electrical conductivity (ECa) of the soil through electrom...

  19. Internalized Stigma of Mental Illness Scale - Thai Version: Translation and Assessment of Psychometric Properties Among Psychiatric Outpatients in Central Thailand.

    Wong-Anuchit, Choochart; Mills, Andrew C; Schneider, Joanne Kraenzle; Rujkorakarn, Darunee; Kerdpongbunchote, Chusri; Panyayong, Benjaporn

    2016-08-01

    This paper reports the translation of the English Internalized Stigma of Mental Illness scale into Thai and assessment of its psychometric properties. After forward- and backward-translation, Thai experts completed the content validity index with item agreements of .86 to 1.00. Data were collected from 390 psychiatric clinic patients in central Thailand using systematic random sampling. Unweighted least squares factor analysis with Promax rotation identified five subscales. Cronbach's alpha for scale reliability was .88, and correlations for construct validity ranged from r=.55 to .69. These findings support the validity and reliability of the Thai version of the scale. PMID:27455917

  20. Optical properties of the micro/nano structures of Morpho butterfly wing scales

    2010-01-01

    The micro/nano structures of the wing scales in Morpho butterfly are responsible for the structural coloration,with a major part ascribed to interference and diffraction of light.The optical properties of the butterfly wings were investigated by simulating a two-dimensional model using rigorous coupled-wave analysis technique.It is proved that they depend strongly on the structural parameters,incidence angle and refractive index.The peak value and the peak wavelength of the reflection efficiency increase as the vertical periodic thickness increases.The peak value decreases observably,while both of the bandwidth and the peak wavelength increase when the number of the vertical periods decreases.Increase of the horizontal periodic width causes a decrease of the peak value and an increase of the peak wavelength,although the variations are small.The peak value decreases distinctly and the peak wavelength increases as the ambient refractive index increases,which corresponds to the variation in ambient conditions.The research reveals the mechanisms of the brilliant structural color in Morpho butterfly,and is of great significance to the design,manufacture and applications of the bionic micro/nano structures for gas detection.

  1. The Psychometric Properties of PHQ-4 Depression and Anxiety Screening Scale Among College Students.

    Khubchandani, Jagdish; Brey, Rebecca; Kotecki, Jerome; Kleinfelder, JoAnn; Anderson, Jason

    2016-08-01

    Depression and anxiety are some of the most common causes of morbidity, social dysfunction, and reduced academic performance in college students. The combination of improved surveillance and access to care would result in better outreach. Brief screening tools can help reach larger populations of college students efficiently. However, reliability and validity of brief screeners for anxiety and depression have not been assessed in college students. Thus, the purpose of this study was to assess in a sample of college students the psychometric properties of PHQ-4, a brief screening tool for depression and anxiety. Undergraduate students were recruited from general education classes at a Midwestern university. Students were given a questionnaire that asked them whether they had been diagnosed by a doctor or health professional with anxiety or depression. Next, they were asked to respond to the items on the PHQ-4 scale. A total of 934 students responded to the survey (response rate=72%). Majority of the participants were females (63%) and Whites (80%). The internal reliability of PHQ-4 was found to be high (α=0.81). Those who were diagnosed with depression or anxiety had statistically significantly higher scores on PHQ-4 (panxiety and depression. The PHQ-4 is a reliable and valid tool that can serve as a mass screener for depression and anxiety in young adults. Widespread implementation of this screening tool should be explored across college campuses. PMID:27455918

  2. Parsec scale polarization properties of the TeV blazar Markarian 421

    Lico, R; Orienti, M; Gomez, J L; Casadio, C; D'Ammando, F; Blasi, M G; Cotton, W; Edwards, P G; Fuhrmann, L; Jorstad, S; Kino, M; Kovalev, Y Y; Krichbaum, T P; Marscher, A P; Paneque, D; Piner, B G; Sokolovsky, K V

    2015-01-01

    In this work we present a polarization analysis at radio frequencies of Markarian 421, one of the closest (z=0.03) TeV blazars. The observations were obtained, both in total and in polarized intensity, with the Very Long Baseline Array (VLBA) at 15, 24, and 43 GHz throughout 2011, with one observation per month (for a total of twelve epochs). We investigate the magnetic field topology and the polarization structure on parsec scale and their evolution with time. We detect polarized emission both in the core and in the jet region, and it varies with frequency, location and time. In the core region we measure a mean fractional polarization of about 1-2%, with a peak of about 4% in March at 43 GHz; the polarization angle is almost stable at 43 GHz, but it shows significant variability in the range 114-173 deg at 15 GHz. In the jet region the polarization properties show a more stable behavior; the fractional polarization is about 16% and the polarization angle is nearly perpendicular to the jet axis. The higher E...

  3. Nonlinear conductive properties and scaling behavior of conductive particle filled high-density polyethylene composites

    ZHENG Qiang; SHEN Lie; LI Wenchun; SONG Yihu; YI Xiaosu

    2005-01-01

    The blends prepared by incorporation of carbon black (CB) or graphite powder (GP) inHto high-density polyethylene (HDPE) matrix have been novel and extensively applied polymeric positive temperature coefficient (PTC) composites. A phenomenological model was proposed on the basis of the GEM equation and the dilution effect of filler volume fraction due to the thermal volume expansion of the polymer matrix. Accordingly, the contribution of the thermal expansion of the matrix to the jump-like PTC transition of the composites was quantitatively estimated and a mechanical explanation was given. It was proved that the contribution of the volume expansion to PTC effect decreased for HDPE/CB composites crosslinked through electron-beam irradiation. Furthermore, the influences of the filler content, temperature and crosslinking on the self-heating behavior as well as the nonlinear conduction characteristics at electrical-thermal equilibrium state were examined. Based on the electric-field and initial resistivity dependence of the self-heating temperature and resistance dependence of the critical field, the mechanisms of the self-heating of the polymeric PTC materials were evaluated. The intrinsic relations between macroscopic electrical properties and microscopic percolation network at electrical-thermal equilibrium state were discussed according to the scaling relationship between the self-heating critical parameter and the conductivity of materials.

  4. Parsec-scale jet properties of the quasar PG 1302$-$102

    Mohan, P; Frey, S; Mangalam, A; Gabanyi, K E; Kun, E

    2016-01-01

    The quasar PG 1302$-$102 is believed to harbour a supermassive binary black hole (SMBBH) system. Using the available 15 GHz and $2-8$ GHz, multi-epoch Very Long Baseline Array data, we constrain the pc-scale jet properties based on the inferred mean proper motion, including a bulk Lorentz factor $\\geq 5.1 \\pm 0.8$, jet inclination angle $\\leq (11.4 \\pm 1.7)$ degrees, projected position angle $= 31.8$ degrees, intrinsic half opening angle $\\leq (0.9 \\pm 0.1)$ degrees and a mean $2-8$ GHz spectral index of 0.31. A general relativistic helical jet model is presented and applied to predict quasi-periodic oscillations of $\\sim$ 10 days, power law power spectrum shape and a contribution of up to $\\sim$ 53 percent to the observed variable core flux density. The model is used to make a case for high resolution, moderately sampled, long duration radio interferometric observations to reveal signatures due to helical knots and distinguish them from those due to SMBBH orbital activity including a phase difference $\\sim \\...

  5. Measurement Properties of the Low Back Activity Confidence Scale (LoBACS).

    Davenport, Todd E; Cleland, Joshua A; Yamada, Kimiko A; Kulig, Kornelia

    2016-06-01

    The purpose of this study was to determine the measurement properties of the Low Back Activity Confidence Scale (LoBACS) in individuals with post-acute low back pain (LBP) receiving nonsurgical intervention, including construct validity, factorial validity, and internal consistency reliability. Data were analyzed from an existing randomized clinical trial involving 112 patients with LBP. Evidence for convergent validity was observed through significant correlations between LoBACS subscale scores and other function, pain, and psychobehavioral measures. LoBACS subscales accounted for 36% of the unique variance in dependent variable measurements, suggesting a satisfactory level of statistical divergence between the LoBACS and other psychobehavioral measurements in this study. Cronbach's α ranged from .88 to .92 for LoBACS subscales, and item-total correlations exceeded .6, indicating high internal consistency reliability. Principal axis factoring confirmed the hypothesized three-subscale structure by correctly classifying 14 of the 15 items. These findings indicate the LoBACS is valid and internally consistent to measure domain-specific self-efficacy beliefs. PMID:24686745

  6. Universal properties of a single polymer chain in slit: Scaling versus MD simulations

    Dimitrov, Dimitar I; Binder, Kurt; Klushin, Leonid I; Skvortsov, Alexander M

    2008-01-01

    We revisit the classical problem of a polymer confined in a slit in both of its static and dynamic aspects. We confirm a number of well known scaling predictions and analyse their range of validity by means of comprehensive Molecular Dynamics simulations using a coarse-grained bead-spring model of a flexible polymer chain. The normal and parallel components of the average end-to-end distance, mean radius of gyration and their distributions, the density profile, the force exerted on the slit walls, and the local bond orientation characteristics are obtained in slits of width $D$ = $4 \\div 10$ (in units of the bead radius) and for chain lengths $N=50 \\div 300$. We demonstrate that a wide range of static chain properties in normal direction can be described {\\em quantitatively} by analytic model - independent expressions in perfect agreement with computer experiment. In particular, the observed profile of confinement-induced bond orientation, is shown to closely match theory predictions. The anisotropy of confin...

  7. Psychometric Properties of the Persian Language Version of the System Usability Scale

    Iman Dianat

    2014-07-01

    Full Text Available Background: The System Usability Scale (SUS is a widely used self–administered instrument for evaluating the usability of a wide range of products and services. The aims of this descriptive- methodological study were to develop and investigate the psychometric properties of the Iranian version of the SUS. Methods: The study was conducted among 202 university students from the Tabriz University of Medical Sciences, Iran. Content validity was evaluated by a panel of 10 experts. Construct validity was assessed by exploratory and confirmatory factor analyses. The internal consistency and test-retest reliability were assessed by Cronbach’s alpha and Intraclass Correlation Coefficient (ICC, respectively. Additionally the feasibility of the measure was judged by ceiling and floor effect. Results: Content validity of the short form of Iranian SUS was established. Factor analyses supported the conceptual uni-dimensionality, and thus confirmed the construct validity of the measure. The internal consistency (α =0.79 and test retest reliability (ICC = 0.96 were both approved and there was also no ceiling nor floor effect. Conclusions: The findings support the use of SUS for both practical and research settings in Iranian population.

  8. Properties of chromia scales on high-temperature alloys used as barriers against hydrogen permeation

    The behaviour of oxide scales grown on high-temperature alloys and their action as diffusion barriers against hydrogen and tritium permeation is described. Static and dynamic permeation measurements, as well as acoustic emission measurements, indicate that chromium oxide scales are superior to scales containing spinel structure of the type Cr2MeO4 (Me = Ni, Fe, Co), whereas spinel structures of the type Cr2MeO4 (Me = Mn, Ti) do not seem to have a negative influence on the barrier action of the scale. The role of oxygen potential with respect to scale composition, mechanical stability and scale growth is described. Hydrogen permeation measurements are very sensitive and are thus able to detect changes in the scale structure. Dynamic measurements combined with static measurements enable us to obtain relevant data on the scale - like diffusivity and solubility of hydrogen in scales. (orig.)

  9. General Relationships between Abiotic Soil Properties and Soil Biota across Spatial Scales and Different Land-Use Types

    Birkhofer, Klaus; Schöning, Ingo; Alt, Fabian; Herold, Nadine; Klarner, Bernhard; Maraun, Mark; Marhan, Sven; Oelmann, Yvonne; Wubet, Tesfaye; Yurkov, Andrey; Begerow, Dominik; Berner, Doreen; Buscot, François; Daniel, Rolf; Diekötter, Tim; Ehnes, Roswitha B.; Erdmann, Georgia; Fischer, Christiane; Foesel, Bärbel; Groh, Janine; Gutknecht, Jessica; Kandeler, Ellen; Lang, Christa; Lohaus, Gertrud; Meyer, Annabel; Nacke, Heiko; Näther, Astrid; Overmann, Jörg; Polle, Andrea; Pollierer, Melanie M.; Scheu, Stefan; Schloter, Michael; Schulze, Ernst-Detlef; Schulze, Waltraud; Weinert, Jan; Weisser, Wolfgang W.; Wolters, Volkmar; Schrumpf, Marion

    2012-01-01

    Very few principles have been unraveled that explain the relationship between soil properties and soil biota across large spatial scales and different land-use types. Here, we seek these general relationships using data from 52 differently managed grassland and forest soils in three study regions spanning a latitudinal gradient in Germany. We hypothesize that, after extraction of variation that is explained by location and land-use type, soil properties still explain significant proportions of variation in the abundance and diversity of soil biota. If the relationships between predictors and soil organisms were analyzed individually for each predictor group, soil properties explained the highest amount of variation in soil biota abundance and diversity, followed by land-use type and sampling location. After extraction of variation that originated from location or land-use, abiotic soil properties explained significant amounts of variation in fungal, meso- and macrofauna, but not in yeast or bacterial biomass or diversity. Nitrate or nitrogen concentration and fungal biomass were positively related, but nitrate concentration was negatively related to the abundances of Collembola and mites and to the myriapod species richness across a range of forest and grassland soils. The species richness of earthworms was positively correlated with clay content of soils independent of sample location and land-use type. Our study indicates that after accounting for heterogeneity resulting from large scale differences among sampling locations and land-use types, soil properties still explain significant proportions of variation in fungal and soil fauna abundance or diversity. However, soil biota was also related to processes that act at larger spatial scales and bacteria or soil yeasts only showed weak relationships to soil properties. We therefore argue that more general relationships between soil properties and soil biota can only be derived from future studies that consider

  10. General relationships between abiotic soil properties and soil biota across spatial scales and different land-use types.

    Klaus Birkhofer

    Full Text Available Very few principles have been unraveled that explain the relationship between soil properties and soil biota across large spatial scales and different land-use types. Here, we seek these general relationships using data from 52 differently managed grassland and forest soils in three study regions spanning a latitudinal gradient in Germany. We hypothesize that, after extraction of variation that is explained by location and land-use type, soil properties still explain significant proportions of variation in the abundance and diversity of soil biota. If the relationships between predictors and soil organisms were analyzed individually for each predictor group, soil properties explained the highest amount of variation in soil biota abundance and diversity, followed by land-use type and sampling location. After extraction of variation that originated from location or land-use, abiotic soil properties explained significant amounts of variation in fungal, meso- and macrofauna, but not in yeast or bacterial biomass or diversity. Nitrate or nitrogen concentration and fungal biomass were positively related, but nitrate concentration was negatively related to the abundances of Collembola and mites and to the myriapod species richness across a range of forest and grassland soils. The species richness of earthworms was positively correlated with clay content of soils independent of sample location and land-use type. Our study indicates that after accounting for heterogeneity resulting from large scale differences among sampling locations and land-use types, soil properties still explain significant proportions of variation in fungal and soil fauna abundance or diversity. However, soil biota was also related to processes that act at larger spatial scales and bacteria or soil yeasts only showed weak relationships to soil properties. We therefore argue that more general relationships between soil properties and soil biota can only be derived from future

  11. Modelling Pesticide Leaching At Column, Field and Catchment Scales Ii. Influence of Soil Variability On Small Scale Transfer Properties

    Roulier, S.; Jarvis, N.

    The aim of this study was to investigate the differences in small scale transfer prop- erties in relation to variability of soil characteristics in a small undulating agricultural catchment (Vemmenhög, 9 km2), where texture and organic C content are strongly related to landscape position (see Gärdenäs et al., this session). Undisturbed soil col- umn samples (20 cm diameter, 20 cm height) were taken at two locations (4 columns at each location): on a hilltop (high clay content), and in a hollow (high C content). Transient leaching experiments for a tracer and a herbicide (MCPA) were carried out in two steps. After a first application of solute and pesticide the columns were ex- posed to natural rainfall. After one pore volume of drainage had flowed through the columns, they were transferred indoors. A second dose of tracer and pesticide was applied, and the columns were irrigated with half a pore volume of natural rainwa- ter. The breakthrough curves obtained for the hilltop columns showed strong evidence of macroporous flow. The flux concentrations and the resident concentration at the end of the experiment measured for the hollow columns suggested that the loss of pesticide from those columns is little. The MACRO model and the inverse modelling package SUFI were used to estimate the small scale parameters for water transfer, so- lute transport, and pesticide. Good agreement was obtained between model and data. Macroporous flow and diffusive transport through hilltop columns was highlighted by the high calibrated values of the effective diffusion pathlength and the dispersivity. As a consequence of the significant organic C content in the hollows, the value of the degradation rate coefficient for hollow columns was important. In both hilltop and hollow columns, the variation of the degradation rate coefficient between the first and the second application of MCPA showed the ability of the micro-organisms to adapt to the pesticide.

  12. Finite-Size Scaling in a Two-Temperature Lattice Gas: a Monte Carlo Study of Critical Properties

    Larsen, Heine; Præstgaard, Eigil; Zia, R.K.P.

    1994-01-01

    We present computer studies of the critical properties of an Ising lattice gas driven to a non-equilibrium steady state by coupling to two temperature baths. Anisotropic scaling, a dominant feature near criticality, is used as a tool to extract the values of the critical temperature and some expo...

  13. Scaling properties of hyperon production in Au+Au collisions at (sNN)=200GeV

    Adams, J.; Bielčík, J.; Bielčíková, J.; Bysterský, Michal; Chaloupka, Petr; Jakl, P.; Kapitán, J.; Kushpil, Vasilij; Lednický, R.; Pachr, M.; Šumbera, Michal

    2007-01-01

    Roč. 98, č. 6 (2007), 062301-062301. ISSN 0031-9007 R&D Projects: GA ČR GA202/04/0793 Institutional research plan: CEZ:AV0Z10480505 Keywords : Scaling properties Subject RIV: BE - Theoretical Physics Impact factor: 6.944, year: 2007

  14. Psychometric Properties of the Liebowitz Social Anxiety Scale in a Longitudinal Study of Latinos with Anxiety Disorders

    Beard, Courtney; Rodriguez, Benjamin F.; Weisberg, Risa B.; Perry, Ashley; Keller, Martin B.

    2012-01-01

    The Liebowitz Social Anxiety Scale (LSAS) is one of the most commonly used measures of social anxiety symptoms. To date, no study has examined its psychometric properties in a Latino sample. The authors examined the reliability, temporal stability, and convergent validity of the LSAS in 73 Latinos diagnosed with an anxiety disorder. The original…

  15. Psychometric properties of the Tuckman Procrastination Scale in a Turkish sample.

    Ozer, Bilge Uzun; Saçkes, Mesut; Tuckman, Bruce W

    2013-12-01

    A stepwise validation procedure was carried out to translate and develop a Turkish version of the Tuckman Procrastination Scale. A total of 858 college students completed the Tuckman Procrastination Scale, the Academic Self-efficacy Scale, and the Rosenberg Self-esteem Scale. Two items in the original scale loaded on a different factor and were removed from the measure. The 14-item scale had a one-factor solution as supported by subsequent confirmatory factor analysis. The Turkish version of the Tuckman Procrastination Scale scores correlated negatively with academic self-efficacy and self-esteem scores. Overall results provided evidence for the validity and the reliability of the scale scores. PMID:24693816

  16. Semi-empirical correction of ab initio harmonic properties by scaling factors: a validated uncertainty model for calibration and prediction

    Pernot, Pascal

    2010-01-01

    Bayesian Model Calibration is used to revisit the problem of scaling factor calibration for semi-empirical correction of ab initio harmonic properties (e.g. vibrational frequencies and zero-point energies). A particular attention is devoted to the evaluation of scaling factor uncertainty, and to its effect on the accuracy of scaled properties. We argue that in most cases of interest the standard calibration model is not statistically valid, in the sense that it is not able to fit experimental calibration data within their uncertainty limits. This impairs any attempt to use the results of the standard model for uncertainty analysis and/or uncertainty propagation. We propose to include a stochastic term in the calibration model to account for model inadequacy. This new model is validated in the Bayesian Model Calibration framework. We provide explicit formulae for prediction uncertainty in typical limit cases: large and small calibration sets of data with negligible measurement uncertainty, and datasets with la...

  17. High temperature structural analysis of a small scale PHE prototype -Analysis considering material properties in weld zone-

    A process heat exchanger (PHE) in a nuclear hydrogen system is a key component for transferring the considerable heat generated in a very high temperature reactor (VHTR) to a chemical reaction that yields a large quantity of hydrogen. A performance test on a small scale PHE prototype made of Hastelloy X is underway in a small scale gas loop at the Korea Atomic Energy Research Institute. Previous research on the high temperature structural analysis of the small scale PHE prototype had been performed using base material properties. In this study, a high temperature structural analysis considering the mechanical properties in the weld zone was performed, and the obtained results were compared with those of the previous research

  18. Optimal sampling and sample preparation for NIR-based prediction of field scale soil properties

    Knadel, Maria; Peng, Yi; Schelde, Kirsten; Thomsen, Anton; Deng, Fan; Humlekrog Greve, Mogens

    2013-04-01

    The representation of local soil variability with acceptable accuracy and precision is dependent on the spatial sampling strategy and can vary with a soil property. Therefore, soil mapping can be expensive when conventional soil analyses are involved. Visible near infrared spectroscopy (vis-NIR) is considered a cost-effective method due to labour savings and relative accuracy. However, savings may be offset by the costs associated with number of samples and sample preparation. The objective of this study was to find the most optimal way to predict field scale total organic carbon (TOC) and texture. To optimize the vis-NIR calibrations the effects of sample preparation and number of samples on the predictive ability of models with regard to the spatial distribution of TOC and texture were investigated. Conditioned Latin hypercube sampling (cLHs) method was used to select 125 sampling locations from an agricultural field in Denmark, using electromagnetic induction (EMI) and digital elevation model (DEM) data. The soil samples were scanned in three states (field moist, air dried and sieved to 2 mm) with a vis-NIR spectrophotometer (LabSpec 5100, ASD Inc., USA). The Kennard-Stone algorithm was applied to select 50 representative soil spectra for the laboratory analysis of TOC and texture. In order to investigate how to minimize the costs of reference analysis, additional smaller subsets (15, 30 and 40) of samples were selected for calibration. The performance of field calibrations using spectra of soils at the three states as well as using different numbers of calibration samples was compared. Final models were then used to predict the remaining 75 samples. Maps of predicted soil properties where generated with Empirical Bayesian Kriging. The results demonstrated that regardless the state of the scanned soil, the regression models and the final prediction maps were similar for most of the soil properties. Nevertheless, as expected, models based on spectra from field

  19. Subsurface structures and properties of a medium-scale peatland area by means of hydrogeophysical methods

    Altdorff, Daniel; van der Kruk, Jan; Bechtold, Michel; Tiemeyer, Bärbel; Huismann, Sander

    2013-04-01

    Intact peatlands are natural sinks of climate-relevant atmospheric CO2 and they are able to store high amounts of organic carbon (C). In addition, intact peatlands are increasingly important given positive effects on biodiversity, hydrological processes and corresponding management issues. Nevertheless, large parts of peatlands in populated areas were modified by human activity during the last centuries. In Germany, more than 90% of the peatlands are drained, mainly for agricultural use. Due to the recent recognition of the positive effects of intact peatlands, there are presently several initiatives for re-wetting parts of these peatlands. However, a restoration to nearly natural conditions needs an evaluation of the current situation as well as an assessment of the restoration potential. Therefore, soil properties like peat layer thickness, bulk density and moisture content need to be known. Non-invasive hydrogeophysical methods offer the possibility for a time and cost-effective characterization of peatlands. In this study, we investigated a medium-scale peatland area (approximately 35 ha) of the 3000 ha large 'Großes Moor' peatland. We present apparent conductivity (ECa) values obtained from Electromagnetic Induction (EMI) measurements representative for three investigation depths (approximately 0.25, 0.5, and 1m). We selected zones with dissimilar ECa to identify areas where strong changes in the subsoil properties with depth are expected (i.e. shallow peat soil on top of sand). Within these areas, additional measurements were made using Ground Penetration Radar (GPR) and soil sampling was performed. In total, six 30 m long GPR profiles and corresponding common midpoint (CMP) measurements were recorded. Additionally, 15 soil cores were taken down to a depth of 0.9 m in order to obtain peat thickness, water content, pore water EC, bulk density (BD), as well as C and N content. Each core was divided into several 5 to 20 cm thick layers to obtain information on

  20. Linking atomic and mesoscopic scales for the modelling of the transport properties of uranium dioxide under irradiation

    Bertolus, Marjorie, E-mail: marjorie.bertolus@cea.fr [CEA, DEN, DEC/SESC, Centre de Cadarache, 13108 Saint-Paul-lez-Durance (France); Freyss, Michel; Dorado, Boris; Martin, Guillaume; Hoang, Kiet; Maillard, Serge; Skorek, Richard; Garcia, Philippe; Valot, Carole [CEA, DEN, DEC/SESC, Centre de Cadarache, 13108 Saint-Paul-lez-Durance (France); Chartier, Alain; Van Brutzel, Laurent; Fossati, Paul [CEA, DEN, DPC/SCCME, 91191 Gif-sur-Yvette (France); Grimes, Robin W.; Parfitt, David C.; Bishop, Clare L.; Murphy, Samuel T.; Rushton, Michael J.D. [Department of Materials, Imperial College London, London SW7 2AZ (United Kingdom); Staicu, Dragos; Yakub, Eugen; Nichenko, Sergii [European Commission, Joint Research Centre, Institute for Transuranium Elements, 76125 Karlsruhe (Germany); and others

    2015-07-15

    This article presents a synthesis of the investigations at the atomic scale of the transport properties of defects and fission gases in uranium dioxide, as well as of the transfer of results from the atomic scale to models at the mesoscopic scale, performed during the F-BRIDGE European project (2008–2012). We first present the mesoscale models used to investigate uranium oxide fuel under irradiation, and in particular the cluster dynamics and kinetic Monte Carlo methods employed to model the behaviour of defects and fission gases in UO{sub 2}, as well as the parameters of these models. Second, we describe briefly the atomic scale methods employed, i.e. electronic structure calculations and empirical potential methods. Then, we show the results of the calculation of the data necessary for the mesoscale models using these atomic scale methods. Finally, we summarise the links built between the atomic and mesoscopic scale by listing the data calculated at the atomic scale which are to be used as input in mesoscale modelling. Despite specific difficulties in the description of fuel materials, the results obtained in F-BRIDGE show that atomic scale modelling methods are now mature enough to obtain precise data to feed higher scale models and help interpret experiments on nuclear fuels. These methods bring valuable insight, in particular the formation, binding and migration energies of point and extended defects, fission product localization, incorporation energies and migration pathways, elementary mechanisms of irradiation induced processes. These studies open the way for the investigation of other significant phenomena involved in fuel behaviour, in particular the thermochemical and thermomechanical properties and their evolution in-pile, complex microstructures, as well as of more complex fuels.

  1. Linking atomic and mesoscopic scales for the modelling of the transport properties of uranium dioxide under irradiation

    This article presents a synthesis of the investigations at the atomic scale of the transport properties of defects and fission gases in uranium dioxide, as well as of the transfer of results from the atomic scale to models at the mesoscopic scale, performed during the F-BRIDGE European project (2008–2012). We first present the mesoscale models used to investigate uranium oxide fuel under irradiation, and in particular the cluster dynamics and kinetic Monte Carlo methods employed to model the behaviour of defects and fission gases in UO2, as well as the parameters of these models. Second, we describe briefly the atomic scale methods employed, i.e. electronic structure calculations and empirical potential methods. Then, we show the results of the calculation of the data necessary for the mesoscale models using these atomic scale methods. Finally, we summarise the links built between the atomic and mesoscopic scale by listing the data calculated at the atomic scale which are to be used as input in mesoscale modelling. Despite specific difficulties in the description of fuel materials, the results obtained in F-BRIDGE show that atomic scale modelling methods are now mature enough to obtain precise data to feed higher scale models and help interpret experiments on nuclear fuels. These methods bring valuable insight, in particular the formation, binding and migration energies of point and extended defects, fission product localization, incorporation energies and migration pathways, elementary mechanisms of irradiation induced processes. These studies open the way for the investigation of other significant phenomena involved in fuel behaviour, in particular the thermochemical and thermomechanical properties and their evolution in-pile, complex microstructures, as well as of more complex fuels

  2. Quantifying the heterogeneity of soil compaction, physical soil properties and soil moisture across multiple spatial scales

    Coates, Victoria; Pattison, Ian; Sander, Graham

    2016-04-01

    England's rural landscape is dominated by pastoral agriculture, with 40% of land cover classified as either improved or semi-natural grassland according to the Land Cover Map 2007. Since the Second World War the intensification of agriculture has resulted in greater levels of soil compaction, associated with higher stocking densities in fields. Locally compaction has led to loss of soil storage and an increased in levels of ponding in fields. At the catchment scale soil compaction has been hypothesised to contribute to increased flood risk. Previous research (Pattison, 2011) on a 40km2 catchment (Dacre Beck, Lake District, UK) has shown that when soil characteristics are homogeneously parameterised in a hydrological model, downstream peak discharges can be 65% higher for a heavy compacted soil than for a lightly compacted soil. However, at the catchment scale there is likely to be a significant amount of variability in compaction levels within and between fields, due to multiple controlling factors. This research focusses in on one specific type of land use (permanent pasture with cattle grazing) and areas of activity within the field (feeding area, field gate, tree shelter, open field area). The aim was to determine if the soil characteristics and soil compaction levels are homogeneous in the four areas of the field. Also, to determine if these levels stayed the same over the course of the year, or if there were differences at the end of the dry (October) and wet (April) periods. Field experiments were conducted in the River Skell catchment, in Yorkshire, UK, which has an area of 120km2. The dynamic cone penetrometer was used to determine the structural properties of the soil, soil samples were collected to assess the bulk density, organic matter content and permeability in the laboratory and the Hydrosense II was used to determine the soil moisture content in the topsoil. Penetration results show that the tree shelter is the most compacted and the open field area

  3. Temporal Variations in the Scaling Properties of Rain Echoes during the Development of a Cold Low in Saskatchewan.

    Lawford, R. G.

    1996-06-01

    A better understanding of the scaling properties of rain could assist in parameterizing rain events in hydrological models and support the development of improved `weather generators.' A technique developed for the analysis of the scaling characteristics of snow patches during melt has been adapted to study the development of rain echoes observed by radar. The technique is applied to echo ensembles detected by a weather radar located at Elbow, Saskatchewan, for a 48-h period from 1800 LST 30 June to 1800 LST 2 July 1991.The scaling properties and other statistical measures of ensembles of radar echoes from 2-km MSL CAPPI (constant-altitude plan position indicator) maps wore analyzed for a 240 km × 240 km square domain centered on Elbow. The 0.2 mm h1 rain rate was used to define the echoes. During the 48-h period, the sizes, numbers, and shapes of echoes within the domain changed considerably as a result of a cold low that intensified just outside the study area and then moved eastward. Analyses of some scaling properties of these ensembles were carried out along with tests of their sensitivity to reflectivity threshold.The echo ensembles were characterized by the perimeter/area and Korcak parameters. The perimeter/area parameter provides a measure of the `roughness' of the edges of the echoes. Values of the perimeter/area parameter from this study agreed well with the results obtained by other investigators who used different data sources and techniques. The Korcak parameter, which represents the `clumpiness' of the pattern, was more variable. Changes in this parameter may serve as a precursor to significant changes in the overall rain pattern. Both the statistical properties and the scaling properties of echo ensembles were found to vary depending on the effects of the dynamic and thermodynamic atmospheric controls on rain formation.

  4. Links between soil properties and steady-state solute transport through cultivated topsoil at the field scale

    Koestel, J. K.; Norgaard, T.; Minh, Luong Nhat;

    2013-01-01

    consequence to larger water saturation and the activation of larger macropores. Our study provides further evidence that it should be possible to estimate solute transport properties from soil properties such as soil texture or bulk density. We also demonstrated that estimation approaches established for the......It is known that solute transport through soil is heterogeneous at all spatial scales. However, little data are available to allow quantification of these heterogeneities at the field scale or larger. In this study, we investigated the spatial patterns of soil properties, hydrologic state variables...... transport was positively correlated with the bulk density and the degree of water saturation. The latter suggests that preferential macropore transport was the dominating transport process. Increased bulk densities were presumably related with a decrease in near-saturated hydraulic conductivities and as a...

  5. Psychometric properties of the Trauma and Distress Scale, TADS, in an adult community sample in Finland

    Raimo K. R. Salokangas

    2016-03-01

    Full Text Available Background: There is increasing evidence that a history of childhood abuse and neglect is not uncommon among individuals who experience mental disorder and that childhood trauma experiences are associated with adult psychopathology. Although several interview and self-report instruments for retrospective trauma assessment have been developed, many focus on sexual abuse (SexAb rather than on multiple types of trauma or adversity. Methods: Within the European Prediction of Psychosis Study, the Trauma and Distress Scale (TADS was developed as a new self-report assessment of multiple types of childhood trauma and distressing experiences. The TADS includes 43 items and, following previous measures including the Childhood Trauma Questionnaire, focuses on five core domains: emotional neglect (EmoNeg, emotional abuse (EmoAb, physical neglect (PhyNeg, physical abuse (PhyAb, and SexAb.This study explores the psychometric properties of the TADS (internal consistency and concurrent validity in 692 participants drawn from the general population who completed a mailed questionnaire, including the TADS, a depression self-report and questions on help-seeking for mental health problems. Inter-method reliability was examined in a random sample of 100 responders who were reassessed in telephone interviews. Results: After minor revisions of PhyNeg and PhyAb, internal consistencies were good for TADS totals and the domain raw score sums. Intra-class coefficients for TADS total score and the five revised core domains were all good to excellent when compared to the interviewed TADS as a gold standard. In the concurrent validity analyses, the total TADS and its all core domains were significantly associated with depression and help-seeking for mental problems as proxy measures for traumatisation. In addition, robust cutoffs for the total TADS and its domains were calculated. Conclusions: Our results suggest the TADS as a valid, reliable, and clinically useful

  6. Cultural Adaptation and Psychometric Properties of the Persian Version of the Circumstances, Motivation, and Readiness Scale

    Norozi, Ensiyeh; Miri, Mohammad Reza; Soltani, Raheleh; Eslami, Ahmad Ali; Harivandi, Ali Reza; Dastjerdi, Reza

    2016-01-01

    Background Treatment motivation has always been an important issue in substance abuse treatment. In recent decades, several instruments have been developed to measure this concept. Objectives In this study, cultural adaptation and psychometric properties of the Persian version of the circumstances, motivation and readiness scale (CMR) are illustrated in a sample of Iranian addicts. Materials and Methods The translation process followed Beaton et al.’s (2000) guideline for the cross-cultural adaptation of self-administered questionnaires, including the steps of translation, synthesis, back translation, expert committee review, and pre-testing. The final version of the Persian CMR was assessed for internal consistency and construct validity (n = 203). Results There was one eliminated item in the cross-cultural adaptation process. Also, four items that had low correlation with the total score were excluded from the questionnaire during the initial analysis. Using the remaining items, Principle axis factoring with Promax rotation was performed and three factors, circumstance, motivation, and readiness, were identified. The secondary order three factor model provided a good statistical and conceptual fit for the data. Internal consistency met the criterion for a reliable measure (Cronbach’s alpha = 0.840). The α range for these identified factors was 0.597 to 0.837. Conclusions Although the CMR was originally designed for use in TC treatment, this study suggests that it is also applicable, with some modifications, in short-term residential camps. Also, it is concluded that the Persian translation of the CMR can be applied for studies among Persian addicts.

  7. Transformation properties of dynamic subgrid-scale models in a frame of reference undergoing rotation

    Horiuti, Kiyosi

    Theoretical consideration is presented for the transformation properties of the subgrid-scale (SGS) models for the SGS stress tensor in a non-inertial frame of reference undergoing rotation. As was previously shown (Speziale, C.G., Geophys. Astrophys. Fluid Dynamics 33, 199 (1985)), an extra correction term is yielded for the SGS stress tensor in the transformation of a rotating frame relative to an inertial framing. We derived the exact expression for the correction term for the spherical Gaussian filter function. Certain transformation rules are imposed on the SGS stress by the derived correction term, namely the SGS stress is not indifferent to a frame rotation, but the divergence of the SGS stress is frame indifferent. Conformity of the modelled SGS stress tensor estimated using the previous dynamic SGS models (the dynamic Smagorinsky, dynamic mixed and nonlinear models) with these transformation rules is examined. It is shown that values for certain model parameters contained in the mixed models can be theoretically determined by imposing these rules. We have conducted the a priori and a postepriori numerical assessments of the SGS models in decaying homogeneous turbulence which is subjected to rotation. All of the previous dynamic models were found to violate the rules except for the nonlinear model. The nonlinear model is form invariant, but the result obtained using the nonlinear model showed significant deviation from the DNS data. Failure of previous models was attributable to insufficient accuracy in approximating the modified cross term in the decomposition of the SGS stress tensor. A dynamic mixed model is proposed to eliminate the truncation error for the modelled correction term, in which multilevel filtering of the velocity field was utilized. The proposed model obeyed the transformation rules when the level of the multifiltering operation was large. It was shown that the defiltered model is derived in the limit of the infinite level of

  8. Pattern scaling effect on the radiative properties of wafer’s surface

    2010-01-01

    This paper presents a parametric study of the radiative properties of patterned wafers with a polysilicon gate array on the Si substrate, considering the effect of wavelength and polarization. The finite-difference time-domain (FDTD) method was employed to examine the pattern scaling effect on the spectral absorptance via numerical solutions of the Maxwell’s equations. The effective medium theory (EMT) was also used to help explain the absorptance predictions. While the gate sizes are very small compared to wavelength, the results show rather unusual phenomena. The absorptance calculated by EMT is in agreement with FDTD in the cases with small gate and period sizes. With the increase of period and decrease of the ratio of the gate width to the grating period, both EMT and FDTD results for the TM (transverse magnetic) mode approach to pure silicon since the grating effect diminishes. However, the error of EMT results for the TE mode in some cases becomes considerable due to the limitation of EMT, which requires the period to be significantly smaller than the wavelength. Besides, the TE (transverse electric) absorptance curve separates from that of plain Si when the wavelength equals the grating period, this is because the gate can interact with its neighbering region by diffraction and the diffraction effects are weak, when the wavelength is small. The peak absorptance can be attributed to the thin film effect. It shows that a slight increase in the gate height can drastically increase the absorptance and the increased gate height shifts the peak absorptance to longer wavelength due to the increase of optical path length in the effective thin film. This work is of great importance for optimization of advanced annealing techniques in semiconductor manufacturing.

  9. Structural and magnetic properties of ultra-small scale eutectic CoFeZr alloys

    Highlights: • Development of ultra-small scale eutectic CoFeZr alloys. • Hardness of 713 VHN was obtained for Co49.2Fe49.2Zr by lamellar spacing of 113 nm. • Highest moment of 1.92 μB at 5 K was obtained for Co49.2Fe49.2Zr. • Decay of magnetization at low temperature can be described by spin wave excitation. - Abstract: Aiming to develop high mechanical strength and toughness by tuning ultrafine lamellar spacing of magnetic eutectic alloys, we report the mechanical and magnetic properties of the binary eutectic alloys Co90.5Zr9.5 and Fe90.2Zr9.8, as well as the pseudo-binary eutectic alloys Co82.4Fe8Zr9.6, Co78Fe12.4Zr9.6 and Co49.2Fe49.2Zr9.6 developed by suction-casting. The lower lamellar spacing around 100 nm of the eutectics Co49.2Fe49.2Zr9.6 yields a high hardness of 713(±20) VHN. Magnetic measurements reveal high magnetic moment of 1.92 μB (at 5 K) and 1.82 μB (at 300 K) per formula unit for this composition. The magnetization vs. applied field data at 5 K show a directional preference to some extent and therefore smaller non-collinear magnetization behavior compared to Co11Zr2 reported in the literature due to exchange frustration and transverse spin freezing owing to the presence of smaller Zr content. The decay of magnetization as a function of temperature along the easy axis of magnetization of all the eutectic compositions can be described fairly well by the spin wave excitation equation ΔM/M(0) = BT3/2 + CT5/2

  10. Psychometric properties of the Trauma and Distress Scale, TADS, in an adult community sample in Finland

    Salokangas, Raimo K. R.; Schultze-Lutter, Frauke; Patterson, Paul; von Reventlow, Heinrich Graf; Heinimaa, Markus; From, Tiina; Luutonen, Sinikka; Hankala, Juha; Kotimäki, Mika; Tuominen, Lauri

    2016-01-01

    Background There is increasing evidence that a history of childhood abuse and neglect is not uncommon among individuals who experience mental disorder and that childhood trauma experiences are associated with adult psychopathology. Although several interview and self-report instruments for retrospective trauma assessment have been developed, many focus on sexual abuse (SexAb) rather than on multiple types of trauma or adversity. Methods Within the European Prediction of Psychosis Study, the Trauma and Distress Scale (TADS) was developed as a new self-report assessment of multiple types of childhood trauma and distressing experiences. The TADS includes 43 items and, following previous measures including the Childhood Trauma Questionnaire, focuses on five core domains: emotional neglect (EmoNeg), emotional abuse (EmoAb), physical neglect (PhyNeg), physical abuse (PhyAb), and SexAb. This study explores the psychometric properties of the TADS (internal consistency and concurrent validity) in 692 participants drawn from the general population who completed a mailed questionnaire, including the TADS, a depression self-report and questions on help-seeking for mental health problems. Inter-method reliability was examined in a random sample of 100 responders who were reassessed in telephone interviews. Results After minor revisions of PhyNeg and PhyAb, internal consistencies were good for TADS totals and the domain raw score sums. Intra-class coefficients for TADS total score and the five revised core domains were all good to excellent when compared to the interviewed TADS as a gold standard. In the concurrent validity analyses, the total TADS and its all core domains were significantly associated with depression and help-seeking for mental problems as proxy measures for traumatisation. In addition, robust cutoffs for the total TADS and its domains were calculated. Conclusions Our results suggest the TADS as a valid, reliable, and clinically useful instrument for assessing

  11. Psychometric Properties of the Persian Version of the Love of Life Scale.

    Vahid, Mohammad Kazem Atef; Dadfar, Mahboubeh; Abdel-Khalek, Ahmed M; Lester, David

    2016-10-01

    A love of life is defined as an overall positive attitude toward life and a liking for life. The present study was designed to evaluate the psychometric characteristics of a Persian version of the Love of Life Scale using a convenience sample of 145 Iranian female volunteer college students (M age = 23.0 years, SD = 3.4). The mean score on the Love of Life Scale was 61.08 (SD = 11.40). A principal component analysis with a Varimax rotation yielded two factors labeled (a) Positive Attitude Towards Life and Happy Consequences of Love of Life and (b) Meaningfulness of Life. Cronbach's alpha was .94 and the one-week test-retest reliability was .85. Love of Life Scale scores had significant positive correlations with scores on the Oxford Happiness Questionnaire, the Satisfaction with Life Scale, the General Self-Efficacy Scale, and the Adult Hope Scale. The scale displayed negative correlations with the Kessler Psychological Distress Scale and the Wish to be Dead Scale. It was concluded that the Persian form of the Love of Life Scale can be recommended for future research on positive psychology. PMID:27597796

  12. Scaling and geometric properties of extensional fracture systems in the proterozoic basement of Yemen. Tectonic interpretation and fluid flow implications

    Le Garzic, Edouard; de L'Hamaide, Thibaut; Diraison, Marc; Géraud, Yves; Sausse, Judith; de Urreiztieta, Marc; Hauville, Benoît; Champanhet, Jean-Michel

    2011-04-01

    Multi-scale mappings of fracture systems in the crystalline basement of Yemen are presented. Fracture datasets are described through statistical analyses of direction, length, spacing, density, and spatial distribution. Results are combined with field observations and can be directly used to model the geometry of the fracture networks in analog basement rocks, from multi-kilometric to decametric scales. The fractured reservoir analog is defined with a dual porosity model in which tectonic and joint systems correspond to the basement reservoir "backbone" and "matrix" respectively. These two end-members reveal contrasting geometrical, reservoir, and scaling properties. In tectonic systems, multi-scale geometries are "self-similar", the fracture network shows fractal behavior (power-law length distribution and clustered spacing), and fault zones show hierarchical organization of geometrical parameters such as length, thickness, and spacing. In joint systems, the fracture network is scale dependent with exponential length distribution, and shows anti-clustered spacing. However, these two end-members have both well-connected properties, with fault zones acting as main drain and joint systems acting as the fluid supply.

  13. An Adaptation of the Emotional Autonomy Scale to the Turkish Adolescents and its Psychometric Properties

    Deniz, Metin; Gaziosmanpaşa Üniversitesi, Eğitim Fakültesi, Psikolojik Danışma ve Rehberlik Anabilim Dalı; Çok, Figen; TED Üniversitesi, Eğitim Bilimleri Bölümü, Rehberlik ve Psikolojik Danışmanlık Anabilim Dalı; Duyan, Veli; Ankara Üniversitesi

    2013-01-01

    The aim of this study was to adapt the Emotional Autonomy Scale (EAS) developed by Steinberg and Silverberg (1986) so as to use it with Turkish adolescents. The original scale is in English and has four factors, consisting of 20 items. Firstly, the original scale was translated into Turkish by six experts from the field and was retranslated by two experts. Later, the original and Turkish forms of the scale were handed to the experts in the field of measurement and evaluation and the last form...

  14. Prediction of transgenic tobacco plant processing properties by ultra scale down and physical property measurement for monoclonal antibody production.

    Hassan, S. Y.

    2008-01-01

    There are numerous potential advantages of producing significant quantities of a monoclonal antibody (MAb) via transgenic tobacco plants over other heterologous production systems, thus paving the way for new prophylactic and therapeutic applications within global human and animal health. However, current information on the key processing factors for large scale production of antibodies from transgenic plants is limited. This thesis presents the issues involved in the production of monoclonal...

  15. Thermal and volumetric properties of complex aqueous electrolyte solutions using the Pitzer formalism - The PhreeSCALE code

    Lach, Adeline; Boulahya, Faïza; André, Laurent; Lassin, Arnault; Azaroual, Mohamed; Serin, Jean-Paul; Cézac, Pierre

    2016-07-01

    The thermal and volumetric properties of complex aqueous solutions are described according to the Pitzer equation, explicitly taking into account the speciation in the aqueous solutions. The thermal properties are the apparent relative molar enthalpy (Lϕ) and the apparent molar heat capacity (Cp,ϕ). The volumetric property is the apparent molar volume (Vϕ). Equations describing these properties are obtained from the temperature or pressure derivatives of the excess Gibbs energy and make it possible to calculate the dilution enthalpy (∆HD), the heat capacity (cp) and the density (ρ) of aqueous solutions up to high concentrations. Their implementation in PHREEQC V.3 (Parkhurst and Appelo, 2013) is described and has led to a new numerical tool, called PhreeSCALE. It was tested first, using a set of parameters (specific interaction parameters and standard properties) from the literature for two binary systems (Na2SO4-H2O and MgSO4-H2O), for the quaternary K-Na-Cl-SO4 system (heat capacity only) and for the Na-K-Ca-Mg-Cl-SO4-HCO3 system (density only). The results obtained with PhreeSCALE are in agreement with the literature data when the same standard solution heat capacity (Cp0) and volume (V0) values are used. For further applications of this improved computation tool, these standard solution properties were calculated independently, using the Helgeson-Kirkham-Flowers (HKF) equations. By using this kind of approach, most of the Pitzer interaction parameters coming from literature become obsolete since they are not coherent with the standard properties calculated according to the HKF formalism. Consequently a new set of interaction parameters must be determined. This approach was successfully applied to the Na2SO4-H2O and MgSO4-H2O binary systems, providing a new set of optimized interaction parameters, consistent with the standard solution properties derived from the HKF equations.

  16. Hydraulic properties and scale effects investigation in regional rock aquifers, south-western Quebec, Canada

    Nastev, M.; Savard, M. M.; Lapcevic, P.; Lefebvre, R.; Martel, R.

    This paper reports on the characterization of hydraulic properties of regional rock aquifers carried out within a groundwater resources assessment project in the St. Lawrence Lowlands of south-western Quebec. To understand the aquifer behavior at both the fracture level and at field scale, hydraulic investigations were carried out using various aquifer tests. The groundwater flow at the local scale is controlled mostly by the fracture system. Results of the constant-head injection tests show a weak decreasing trend of hydraulic conductivity with depth indicating that a major part of the groundwater flow occurs in the first meters of the rock sequence. At the regional scale, the equivalent porous media approach is applicable. The hydraulic conductivity measurements were correlated to the scale of the aquifer tests expressed with the investigated aquifer volume. A simple interpolation procedure for the hydraulic conductivity field was developed based on the distance between field measurements and the tested aquifer volumes. The regional distribution of the hydraulic conductivity for the major fractured aquifer units indicates that dolostone is the most permeable whereas sandstone and crystalline rocks are the least permeable units. Este artículo trata de la caracterización de las propiedades hidráulicas en acuíferos regionales rocosos, la cual se llevó a cabo dentro del proyecto de evaluación de los recursos de agua subterránea en St. Lawrence Lowlands al suroeste de Quebec. Para entender el comportamiento del acuífero tanto a nivel de fractura como a escala del campo, se ejecutaron investigaciones hidráulicas usando varias pruebas de acuífero. El flujo del agua subterránea a escala local está controlado principalmente por el sistema de fracturas. Los resultados de las pruebas de inyección con cabeza constante muestran una tendencia decreciente débil de la conductividad hidráulica con la profundidad, indicando que la mayor parte del flujo de agua

  17. Structure-Property Relationships in Atomic-Scale Junctions: Histograms and Beyond.

    Hybertsen, Mark S; Venkataraman, Latha

    2016-03-15

    Over the past 10 years, there has been tremendous progress in the measurement, modeling and understanding of structure-function relationships in single molecule junctions. Numerous research groups have addressed significant scientific questions, directed both to conductance phenomena at the single molecule level and to the fundamental chemistry that controls junction functionality. Many different functionalities have been demonstrated, including single-molecule diodes, optically and mechanically activated switches, and, significantly, physical phenomena with no classical analogues, such as those based on quantum interference effects. Experimental techniques for reliable and reproducible single molecule junction formation and characterization have led to this progress. In particular, the scanning tunneling microscope based break-junction (STM-BJ) technique has enabled rapid, sequential measurement of large numbers of nanoscale junctions allowing a statistical analysis to readily distinguish reproducible characteristics. Harnessing fundamental link chemistry has provided the necessary chemical control over junction formation, enabling measurements that revealed clear relationships between molecular structure and conductance characteristics. Such link groups (amines, methylsuflides, pyridines, etc.) maintain a stable lone pair configuration that selectively bonds to specific, undercoordinated transition metal atoms available following rupture of a metal point contact in the STM-BJ experiments. This basic chemical principle rationalizes the observation of highly reproducible conductance signatures. Subsequently, the method has been extended to probe a variety of physical phenomena ranging from basic I-V characteristics to more complex properties such as thermopower and electrochemical response. By adapting the technique to a conducting cantilever atomic force microscope (AFM-BJ), simultaneous measurement of the mechanical characteristics of nanoscale junctions as they

  18. [Morningness-Eveningness for Children Scale: psychometric properties and month of birth effect].

    Caci, H; Robert, P; Dossios, C; Boyer, P

    2005-01-01

    There is strong evidence that individuals can be arranged on a continuum from Eveningness to Morningness reflecting their preferred time range for different activities. This preference, which mostly reflects the phase of the circadian pacemaker, is determined in part by mutations on the CLOCK gene, and by environmental factors such as the month of birth. It has been suggested that eveningness might be a susceptibility factor for depressive disorders. Two self-rated questionnaires are available (the Morningness-Eveningness Questionnaire, MEQ, and the Composite Scale for Morningness) and have been adapted for use with youngsters: the Junior-MEQ and the Morningness-Eveningness Scale for Children (MESC), respectively. Most studies concern adult samples, but it is accepted that puberty is associated with a phase delay in the circadian pacemaker die a shift towards eveningness) occuring around age 12 in both genders. In this study, we examined the psychometric properties of the French version of the MESC in 3 independent samples of adolescents (total n = 392) recruited in the community or during hospitalization in paediatric department, most of them after they attempted suicide. A three-way ANCOVA showed no gender or age effect but rather a strong group effect: hospitalized adolescents scored about 3 points below the community samples (ie towards an eveningness tendency). In each sample, the internal consistency for this 10-item measure was satisfactory (mean alpha = 0.76) and the same two-factor structure was found (Morningness and Planification) as shown by procrustes rotations. As expected, there was a negative correlation between the MESC scores and reported times of rising, of going to bed, of best intellectual and physical performances, but no correlation with the number of minutes of sleep needed. The test-retest stability was acceptable within a 8-month delay although the sample size was limited (n = 20). In line with literature data, we found a modest negative

  19. Structural and magnetic properties of ultra-small scale eutectic CoFeZr alloys

    Manjura Hoque, S. [Dept. of Materials Engineering, Indian Institute of Science, Bangalore (India); Materials Science Division, Atomic Energy Centre, Bangladesh Atomic Energy Commission, Dhaka (Bangladesh); Makineni, S.K. [Dept. of Materials Engineering, Indian Institute of Science, Bangalore (India); Pal, A.; Ayyub, P. [Dept. of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Mumbai (India); Chattopadhyay, K. [Dept. of Materials Engineering, Indian Institute of Science, Bangalore (India)

    2015-01-25

    Highlights: • Development of ultra-small scale eutectic CoFeZr alloys. • Hardness of 713 VHN was obtained for Co{sub 49.2}Fe{sub 49.2}Zr by lamellar spacing of 113 nm. • Highest moment of 1.92 μ{sub B} at 5 K was obtained for Co{sub 49.2}Fe{sub 49.2}Zr. • Decay of magnetization at low temperature can be described by spin wave excitation. - Abstract: Aiming to develop high mechanical strength and toughness by tuning ultrafine lamellar spacing of magnetic eutectic alloys, we report the mechanical and magnetic properties of the binary eutectic alloys Co{sub 90.5}Zr{sub 9.5} and Fe{sub 90.2}Zr{sub 9.8}, as well as the pseudo-binary eutectic alloys Co{sub 82.4}Fe{sub 8}Zr{sub 9.6}, Co{sub 78}Fe{sub 12.4}Zr{sub 9.6} and Co{sub 49.2}Fe{sub 49.2}Zr{sub 9.6} developed by suction-casting. The lower lamellar spacing around 100 nm of the eutectics Co{sub 49.2}Fe{sub 49.2}Zr{sub 9.6} yields a high hardness of 713(±20) VHN. Magnetic measurements reveal high magnetic moment of 1.92 μ{sub B} (at 5 K) and 1.82 μ{sub B} (at 300 K) per formula unit for this composition. The magnetization vs. applied field data at 5 K show a directional preference to some extent and therefore smaller non-collinear magnetization behavior compared to Co{sub 11}Zr{sub 2} reported in the literature due to exchange frustration and transverse spin freezing owing to the presence of smaller Zr content. The decay of magnetization as a function of temperature along the easy axis of magnetization of all the eutectic compositions can be described fairly well by the spin wave excitation equation ΔM/M(0) = BT{sup 3/2} + CT{sup 5/2}.

  20. Parsec-Scale Kinematic and Polarization Properties of MOJAVE AGN Jets

    Lister Matthew L.

    2013-12-01

    Full Text Available We describe the parsec-scale kinematics and statistical polarization properties of 200 AGN jets based on 15 GHz VLBA data obtained between 1994 Aug 31 and 2011 May 1. Nearly all of the 60 most heavily observed jets show significant changes in their innermost position angle over a 12 to 16 year interval, ranging from 10° to 150° on the sky, corresponding to intrinsic variations of ~ 0.5° to ~ 2°. The BL Lac jets show smaller variations than quasars. Roughly half of the heavily observed jets show systematic position angle trends with time, and 20 show indications of oscillatory behavior. The time spans of the data sets are too short compared to the fitted periods (5 to 12 y, however, to reliably establish periodicity. The rapid changes and large jumps in position angle seen in many cases suggest that the superluminal AGN jet features occupy only a portion of the entire jet cross section, and may be energized portions of thin instability structures within the jet. We have derived vector proper motions for 887 moving features in 200 jets having at least five VLBA epochs. For 557 well-sampled features, there are sufficient data to additionally study possible accelerations. The moving features are generally non-ballistic, with 70% of the well-sampled features showing either significant accelerations or non-radial motions. Inward motions are rare (2% of all features, are slow (< 0.1 mas per y, are more prevalent in BL Lac jets, and are typically found within 1 mas of the unresolved core feature. There is a general trend of increasing apparent speed with distance down the jet for both radio galaxies and BL Lac objects. In most jets, the speeds of the features cluster around a characteristic value, yet there is a considerable dispersion in the distribution. Orientation variations within the jet cannot fully account for the dispersion, implying that the features have a range of Lorentz factor and/or pattern speed. Very slow pattern speed features are

  1. High Contrast Imaging with Spitzer : Constraining the Frequency of Giant Planets out to 1000 AU separations

    Durkan, Stephen; Carson, Joseph

    2016-01-01

    We report results of a re-analysis of archival Spitzer IRAC direct imaging surveys encompassing a variety of nearby stars. Our sample is generated from the combined observations of 73 young stars (median age, distance, spectral type = 85 Myr, 23.3 pc, G5) and 48 known exoplanet host stars with unconstrained ages (median distance, spectral type = 22.6 pc, G5). While the small size of Spitzer provides a lower resolution than 8m-class AO-assisted ground based telescopes, which have been used for constraining the frequency of 0.5 - 13 $M_J$ planets at separations of $10 - 10^2$ AU, its exquisite infrared sensitivity provides the ability to place unmatched constraints on the planetary populations at wider separations. Here we apply sophisticated high-contrast techniques to our sample in order to remove the stellar PSF and open up sensitivity to planetary mass companions down to 5\\arcsec\\ separations. This enables sensitivity to 0.5 - 13 $M_J$ planets at physical separations on the order of $10^2 - 10^3$ AU , allow...

  2. Fragmentation of massive dense cores down to ≲ 1000 AU: Relation between fragmentation and density structure

    In order to shed light on the main physical processes controlling fragmentation of massive dense cores, we present a uniform study of the density structure of 19 massive dense cores, selected to be at similar evolutionary stages, for which their relative fragmentation level was assessed in a previous work. We inferred the density structure of the 19 cores through a simultaneous fit of the radial intensity profiles at 450 and 850 μm (or 1.2 mm in two cases) and the spectral energy distribution, assuming spherical symmetry and that the density and temperature of the cores decrease with radius following power-laws. Even though the estimated fragmentation level is strictly speaking a lower limit, its relative value is significant and several trends could be explored with our data. We find a weak (inverse) trend of fragmentation level and density power-law index, with steeper density profiles tending to show lower fragmentation, and vice versa. In addition, we find a trend of fragmentation increasing with density within a given radius, which arises from a combination of flat density profile and high central density and is consistent with Jeans fragmentation. We considered the effects of rotational-to-gravitational energy ratio, non-thermal velocity dispersion, and turbulence mode on the density structure of the cores, and found that compressive turbulence seems to yield higher central densities. Finally, a possible explanation for the origin of cores with concentrated density profiles, which are the cores showing no fragmentation, could be related with a strong magnetic field, consistent with the outcome of radiation magnetohydrodynamic simulations.

  3. Fragmentation of massive dense cores down to ~1000 AU: Relation between fragmentation and density structure

    Palau, Aina; Girart, J M; Fuente, A; Fontani, F; Commercon, B; Busquet, G; Bontemps, S; Sanchez-Monge, A; Zapata, L A; Zhang, Q; Hennebelle, P; Di Francesco, J

    2014-01-01

    In order to shed light on the main physical processes controlling fragmentation of massive dense cores, we present a uniform study of the density structure of 19 massive dense cores, selected to be at similar evolutionary stages, for which their relative fragmentation level was assessed in a previous work. We inferred the density structure of the 19 cores through a simultaneous fit of the radial intensity profiles at 450 and 850 micron (or 1.2 mm in two cases) and the Spectral Energy Distribution, assuming spherical symmetry and that the density and temperature of the cores decrease with radius following power-laws. We find a weak (inverse) trend of fragmentation level and density power-law index, with steeper density profiles tending to show lower fragmentation, and vice versa. In addition, we find a trend of fragmentation increasing with density within a given radius, which arises from a combination of flat density profile and high central density and is consistent with Jeans fragmentation. We considered th...

  4. Fragmentation of massive dense cores down to ≲ 1000 AU: Relation between fragmentation and density structure

    Palau, Aina; Girart, Josep M. [Institut de Ciències de l' Espai (CSIC-IEEC), Campus UAB-Facultat de Ciències, Torre C5-parell 2, E-08193 Bellaterra, Catalunya (Spain); Estalella, Robert [Departament d' Astronomia i Meteorologia (IEEC-UB), Institut de Ciències del Cosmos, Universitat de Barcelona, Martí i Franquès, 1, E-08028 Barcelona (Spain); Fuente, Asunción [Observatorio Astronómico Nacional, P.O. Box 112, E-28803 Alcalá de Henares, Madrid (Spain); Fontani, Francesco; Sánchez-Monge, Álvaro [Osservatorio Astrofisico di Arcetri, INAF, Lago E. Fermi 5, I-50125 Firenze (Italy); Commerçon, Benoit; Hennebelle, Patrick [Laboratoire de Radioastronomie, UMR CNRS 8112, École Normale Supérieure et Observatoire de Paris, 24 rue Lhomond, F-75231 Paris Cedex 05 (France); Busquet, Gemma [INAF-Istituto di Astrofisica e Planetologia Spaziali, Area di Recerca di Tor Vergata, Via Fosso Cavaliere 100, I-00133 Roma (Italy); Bontemps, Sylvain [Université de Bordeaux, LAB, UMR 5804, F-33270 Floirac (France); Zapata, Luis A. [Centro de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de México, P.O. Box 3-72, 58090 Morelia, Michoacán (Mexico); Zhang, Qizhou [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Di Francesco, James, E-mail: palau@ieec.uab.es [Department of Physics and Astronomy, University of Victoria, P.O. Box 355, STN CSC, Victoria, BC, V8W 3P6 (Canada)

    2014-04-10

    In order to shed light on the main physical processes controlling fragmentation of massive dense cores, we present a uniform study of the density structure of 19 massive dense cores, selected to be at similar evolutionary stages, for which their relative fragmentation level was assessed in a previous work. We inferred the density structure of the 19 cores through a simultaneous fit of the radial intensity profiles at 450 and 850 μm (or 1.2 mm in two cases) and the spectral energy distribution, assuming spherical symmetry and that the density and temperature of the cores decrease with radius following power-laws. Even though the estimated fragmentation level is strictly speaking a lower limit, its relative value is significant and several trends could be explored with our data. We find a weak (inverse) trend of fragmentation level and density power-law index, with steeper density profiles tending to show lower fragmentation, and vice versa. In addition, we find a trend of fragmentation increasing with density within a given radius, which arises from a combination of flat density profile and high central density and is consistent with Jeans fragmentation. We considered the effects of rotational-to-gravitational energy ratio, non-thermal velocity dispersion, and turbulence mode on the density structure of the cores, and found that compressive turbulence seems to yield higher central densities. Finally, a possible explanation for the origin of cores with concentrated density profiles, which are the cores showing no fragmentation, could be related with a strong magnetic field, consistent with the outcome of radiation magnetohydrodynamic simulations.

  5. Exploring the bulk of the BL Lac object population: parsec scale radio properties and gamma ray emission

    Giovannini G.

    2013-12-01

    Full Text Available BL Lac objects have been found to be the largest population of emitters in gamma-ray band. However, since they are relatively weak radio sources, their parsec scale structure and most of their radio properties are poorly known. To increase our knowledge of the BL Lac object population, we selected a sample of BL Lacs from the BZ Cat at low redshift (z < 0.2, with no constrain on the radio flux density and gamma-ray activity. We present here the results of a first VLBA observation at 8 and 15 GHz and shortly discuss their properties

  6. Do property rights and contract farming matter for rural development? Evidence from a large-scale investment in Ghana

    Väth, Susanne; Kirk, Michael

    2014-01-01

    With the rising demand for agricultural land, land deals must be designed to benefit not only the investors but also the local population. This paper looks at two ways this might be done for farmers in the vicinity of a large-scale oil palm investment in Ghana: contract farming and secure property rights to land. We compare farmers to whom outgrower contracts were allocated, in a quasi-natural experiment, with independent oil palm growers. We find that property rights have a significantly pos...

  7. Career Adapt-Abilities Scale--Brazilian Form: Psychometric Properties and Relationships to Personality

    Teixeira, Marco Antonio Pereira; Bardagi, Marucia Patta; Lassance, Maria Celia Pacheco; Magalhaes, Mauro de Oliveira; Duarte, Maria Eduarda

    2012-01-01

    The Career Adapt-Abilities Scale--Brazilian Form (CAASBrazil) consists of four scales which measure concern, control, curiosity, and confidence as psychosocial resources for managing occupational transitions, developmental tasks, and work traumas. Internal consistency estimates for the subscale and total scores ranged from good to excellent. The…

  8. Psychometric Properties of the Children's Scale of Hostility and Aggression: Reactive/Proactive (C-SHARP)

    Farmer, Cristan A.; Aman, Michael G.

    2010-01-01

    Although often lacking "malice", aggression is fairly common in children with intellectual or developmental disability (I/DD). Despite this, there are no scales available that are appropriate for an in-depth analysis of aggressive behavior in this population. Such scales are needed for the study of aggressive behavior, which is a common target…

  9. Career Adapt-Abilities Scale--Portugal Form: Psychometric Properties and Relationships to Employment Status

    Duarte, M. Eduarda; Soares, M. C.; Fraga, S.; Rafael, M.; Lima, M. R.; Paredes, I.; Agostinho, R.; Djalo, A.

    2012-01-01

    The Career-Adaptabilities Scale (CAAS)--Portugal Form consists of four scales, each with seven items, which measure concern, control, curiosity, and confidence as psychosocial resources for managing occupational transitions, developmental tasks, and work traumas. Internal consistency estimates for the subscale and total scores ranged from good to…

  10. Psychometric properties of the extended Care Dependency Scale for older persons in Egypt

    Boggatz, Thomas; Farid, Tamer; Mohammedin, Ahmed; Dijkstra, Ate; Lohrmann, Christa; Dassen, Theo

    2009-01-01

    Aim. The aim of this study was to determine the validity and reliability of the modified Arabic Care Dependency Scale for self-assessment of older persons in Egypt and to compare these self-assessments to proxy assessments by care givers and family members. Background. The Care Dependency Scale is a

  11. Psychometric properties of the brief version of the Fear of Negative Evaluation Scale in a Turkish sample.

    Koydemir, Selda; Demir, Ayhan

    2007-06-01

    The purpose of the study was to report initial data on the psychometric properties of the Brief Fear of Negative Evaluation Scale. The scale was applied to a nonclinical sample of 250 (137 women, 113 men) Turkish undergraduate students selected randomly from Middle East Technical University. Their mean age was 20.4 yr. (SD= 1.9). The factor structure of the Turkish version, its criterion validity, and internal reliability coefficients were assessed. Although maximum likelihood factor analysis initially indicated that the scale had only one factor, a forced two-factor solution accounted for more variance (61%) in scale scores than a single factor. The straightforward items loaded on the first factor, and the reverse-coded items loaded on the second factor. The total score was significantly positively correlated with scores on the Revised Cheek and Buss Shyness Scale and significantly negatively correlated with scores on the Rosenberg Self-Esteem Scale. Factor 1 (straightforward items) correlated more highly with both Shyness and Self-esteem than Factor 2 (reverse-coded items). Internal consistency estimate was .94 for the Total scores, .91 for the Factor 1 (straightforward items), and .87 for the Factor 2 (reverse-coded items). No sex differences were evident for Fear of Negative Evaluation. PMID:17688107

  12. Length-scale dependent mechanical properties of Al-Cu eutectic alloy: Molecular dynamics based model and its experimental verification

    Tiwary, C. S., E-mail: cst.iisc@gmail.com; Chattopadhyay, K. [Department of Materials Engineering, Indian Institute of Science, Bangalore 560012 (India); Chakraborty, S.; Mahapatra, D. R. [Department of Aerospace Engineering, Indian Institute of Science, Bangalore 560012 (India)

    2014-05-28

    This paper attempts to gain an understanding of the effect of lamellar length scale on the mechanical properties of two-phase metal-intermetallic eutectic structure. We first develop a molecular dynamics model for the in-situ grown eutectic interface followed by a model of deformation of Al-Al{sub 2}Cu lamellar eutectic. Leveraging the insights obtained from the simulation on the behaviour of dislocations at different length scales of the eutectic, we present and explain the experimental results on Al-Al{sub 2}Cu eutectic with various different lamellar spacing. The physics behind the mechanism is further quantified with help of atomic level energy model for different length scale as well as different strain. An atomic level energy partitioning of the lamellae and the interface regions reveals that the energy of the lamellae core are accumulated more due to dislocations irrespective of the length-scale. Whereas the energy of the interface is accumulated more due to dislocations when the length-scale is smaller, but the trend is reversed when the length-scale is large beyond a critical size of about 80 nm.

  13. Length-scale dependent mechanical properties of Al-Cu eutectic alloy: Molecular dynamics based model and its experimental verification

    This paper attempts to gain an understanding of the effect of lamellar length scale on the mechanical properties of two-phase metal-intermetallic eutectic structure. We first develop a molecular dynamics model for the in-situ grown eutectic interface followed by a model of deformation of Al-Al2Cu lamellar eutectic. Leveraging the insights obtained from the simulation on the behaviour of dislocations at different length scales of the eutectic, we present and explain the experimental results on Al-Al2Cu eutectic with various different lamellar spacing. The physics behind the mechanism is further quantified with help of atomic level energy model for different length scale as well as different strain. An atomic level energy partitioning of the lamellae and the interface regions reveals that the energy of the lamellae core are accumulated more due to dislocations irrespective of the length-scale. Whereas the energy of the interface is accumulated more due to dislocations when the length-scale is smaller, but the trend is reversed when the length-scale is large beyond a critical size of about 80 nm.

  14. Investigating the psychometric properties of the Jefferson Scale of Physician Empathy in a sample of Malaysian medical students

    Spasenoska M; Costello S; Williams B

    2016-01-01

    Marija Spasenoska,1 Shane Costello,1 Brett Williams2 1Faculty of Education, 2Department of Community Emergency Health and Paramedic Practice, Monash University, Melbourne, VIC, Australia Objective: The purpose of this present study was to investigate the psychometric properties of the Jefferson Scale of Physician Empathy – student version (JSPE-S). Subjects and methods: This study recruited 193 Malaysian medical students enrolled in year one and year two studies. A principal-component a...

  15. Psychometric properties of the Norwegian version of the Evidence-Based Practice Attitude Scale (EBPAS): to measure implementation readiness

    Egeland, Karina M.; Ruud, Torleif; Ogden, Terje; Lindstrøm, Jonas Christoffer; Heiervang, Kristin Sverdvik

    2016-01-01

    Background Attitudes can be a precursor to the decision of whether or not to try a new practice. In order to tailor the implementation of evidence-based practices (EBPs) in mental health settings, we must first consider practitioner attitudes towards EBP adoption. To assess these attitudes, the Evidence-Based Practice Attitude Scale (EBPAS) was developed. The purpose of this study was to investigate the psychometric properties of the Norwegian version of the EBPAS, and to examine differences ...

  16. Psychometric properties of the Children’s Revised Impact of Events Scale (CRIES) with Bangladeshi children and adolescents

    Farah Deeba; Rapee, Ronald M; Tania Prvan

    2014-01-01

    Identification of possible cases suffering post-traumatic stress disorder (PTSD) is important, especially in developing countries where traumatic events are typically prevalent. The Children’s Revised Impact of Events Scale is a reliable and valid measure that has two brief versions (13 items and 8 items) to assess reactions to traumatic events among young people. The current study evaluated the psychometric properties of both versions of the CRIES in a sample of 1,342 children and adolescent...

  17. Scale effects of nanomechanical properties and deformation behavior of Au nanoparticle and thin film using depth sensing nanoindentation

    Dave Maharaj; Bharat Bhushan

    2014-01-01

    Nanoscale research of bulk solid surfaces, thin films and micro- and nano-objects has shown that mechanical properties are enhanced at smaller scales. Experimental studies that directly compare local with global deformation are lacking. In this research, spherical Au nanoparticles, 500 nm in diameter and 100 nm thick Au films were selected. Nanoindentation (local deformation) and compression tests (global deformation) were performed with a nanoindenter using a sharp Berkovich tip and a flat p...

  18. The Effortful Control Scale for adults: psychometric properties of the Catalan version and its relationship to cognitive emotion regulation

    Miquel Tortella-Feliu; Ignacio Ibáñez; Gloria García de la Banda; Maria Balle; Blanca Aguayo-Siquier; Alfonso Morillas-Romero; Jordi Llabrés

    2013-01-01

    The goals of this study were (a) to examine the psychometric properties of a Catalan version of the Effortful control scale of the Adult Temperament Questionnaire short-form and (b) to analyze the relationships among effortful control (EC), negative affectivity (NA), and the use of negative cognitive emotion regulation (ER) strategies. In a sample of 353 college students, the instrument presents acceptable internal consistency, temporal stability and convergent validity; however, in general, ...

  19. Evaluation of Psychometric Properties of the Malay Version Perceived Stress Scale in Two Occupational Settings In Malaysia

    Al-Dubai, SAR; Ganasegeran, K; Barua, A; Rizal, AM; Rampal, KG

    2014-01-01

    Background: The 10-item version of Perceived Stress Scale (PSS-10) is a widely used tool to measure stress. The Malay version of the PSS-10 has been validated among Malaysian Medical Students. However, studies have not been conducted to assess its validity in occupational settings. Aim: The aim of this study is to assess the psychometric properties of the Malay version of the PSS-10 in two occupational setting in Malaysia. Subjects and Methods: This study was conducted among 191 medical resid...

  20. Psychometric Properties of the Diabetes Management Self-Efficacy Scale in Korean Patients with Type 2 Diabetes

    Eun-Hyun Lee; Jaap van der Bijl; Shortridge-Baggett, Lillie M.; Seung Jin Han; Seung Hei Moon

    2015-01-01

    Objectives. The aims of this study were to perform a cultural translation of the DMSES and evaluate the psychometric properties of the translated scale in a Korean population with type 2 diabetics. Methods. This study was conducted in patients with diabetes recruited from university hospitals. The first stage of this study involved translating the DMSES into Korean using a forward- and backward-translation technique. The content validity was assessed by an expert group. In the second stage, t...

  1. Metric properties of the Achenbach's Youth Self-Report (YSR scale

    Karmen Novak

    2002-12-01

    Full Text Available Two problems regarding Youth Self-Report (YSR in translation to Slovene language and modifications are discussed. The scale evaluates general psychopathology. YSR consists of eight scales (Withdrawn, Somatic complaints, Anxious/depressed, Social problems, Thought problems, Attention problems, Delinquent behavior, Agressive behavior and two general factors (internalizing, externalizing. Objective of the first part is to determine item and scale discrimination between referred and non-referred adolescents (applicability in Slovene culture. The second objective is to determine the prediction value by comparing these diagnoses to ICD-10 diagnoses. YSRs were completed by referred and non-referred adolescents (11-18 years matched by gender, age and socio-economic status. The comparison showed high reliability of some scales. The majority of scales as well as both general factors discriminate well between referred and non-referred youths. Some scales, however, have big discriminant power on sex and age. It was found out that YSR can predict well some of the ICD-10 diagnoses (conduct disorder, posttraumatic stress disorder and attention deficit and hyperactivity disorder while it is inappropriate to predict other diagnoses. Suggestions of how to change expressions at some items in Slovene version were made. Besides, more exact names of some scales are required.

  2. Using scale dependent variation in soil properties to describe soil landscape relationships through DSM

    Corstanje, Ronald; Mayr, Thomas

    2016-04-01

    DSM formalizes the relationship between soil forming factors and the landscape in which they are formed and aims to capture and model the intrinsic spatial variability naturally observed in soils. Covariates, the landscape factors recognized as governing soil formation, vary at different scales and this spatial variation at some scales may be more strongly correlated with soil than at others. Soil forming factors have different domains with distinctive scales, for example geology operates at a coarser scale than land use. By understanding the quantitative relationships between soil and soil forming factors, and their scale dependency, we can start determining the importance of landscape level processes on the formation and observed variation in soils. Three study areas, covered by detailed reconnaissance soil survey, were identified in the Republic of Ireland. Their different pedological and geomorphological characteristics allowed to test scale dependent behaviors across the spectrum of conditions present in the Irish landscape. We considered here three approaches, i) an empirical diagnostic tool in which DSM was applied across a range of scales (20 to 260 m2), ii) the application of wavelets to decompose the DEMs into a series of independent components at varying scales and then used in DSM and finally, iii) a multiscale, window based geostatistical based approach. Applied as a diagnostic approach, we found that wavelets and window based, multiscale geostatistics were effective in identifying the main scales of interaction of the key soil landscape factors (e.g. terrain, geology, land use etc.) and in partitioning the landscape accordingly, we were able to accurately reproduce the observed spatial variation in soils.

  3. Scaling properties of adsorption energies for hydrogen-containing molecules on transition-metal surfaces

    Abild-Pedersen, Frank; Greeley, Jeffrey Philip; Studt, Felix;

    2007-01-01

    Density functional theory calculations are presented for CHx, x=0,1,2,3, NHx, x=0,1,2, OHx, x=0,1, and SHx, x=0,1 adsorption on a range of close-packed and stepped transition-metal surfaces. We find that the adsorption energy of any of the molecules considered scales approximately with the adsorp...... adsorption energy of the central, C, N, O, or S atom, the scaling constant depending only on x. A model is proposed to understand this behavior. The scaling model is developed into a general framework for estimating the reaction energies for hydrogenation and dehydrogenation reactions....

  4. Plasma and cold sprayed aluminum carbon nanotube composites: Quantification of nanotube distribution and multi-scale mechanical properties

    Bakshi, Srinivasa Rao

    Carbon nanotubes (CNT) could serve as potential reinforcement for metal matrix composites for improved mechanical properties. However dispersion of carbon nanotubes (CNT) in the matrix has been a longstanding problem, since they tend to form clusters to minimize their surface area. The aim of this study was to use plasma and cold spraying techniques to synthesize CNT reinforced aluminum composite with improved dispersion and to quantify the degree of CNT dispersion as it influences the mechanical properties. Novel method of spray drying was used to disperse CNTs in Al-12 wt.% Si prealloyed powder, which was used as feedstock for plasma and cold spraying. A new method for quantification of CNT distribution was developed. Two parameters for CNT dispersion quantification, namely Dispersion parameter (DP) and Clustering Parameter (CP) have been proposed based on the image analysis and distance between the centers of CNTs. Nanomechanical properties were correlated with the dispersion of CNTs in the microstructure. Coating microstructure evolution has been discussed in terms of splat formation, deformation and damage of CNTs and CNT/matrix interface. Effect of Si and CNT content on the reaction at CNT/matrix interface was thermodynamically and kinetically studied. A pseudo phase diagram was computed which predicts the interfacial carbide for reaction between CNT and Al-Si alloy at processing temperature. Kinetic aspects showed that Al4C3 forms with Al-12 wt.% Si alloy while SiC forms with Al-23wt.% Si alloy. Mechanical properties at nano, micro and macro-scale were evaluated using nanoindentation and nanoscratch, microindentation and bulk tensile testing respectively. Nano and micro-scale mechanical properties (elastic modulus, hardness and yield strength) displayed improvement whereas macro-scale mechanical properties were poor. The inversion of the mechanical properties at different scale length was attributed to the porosity, CNT clustering, CNT-splat adhesion and Al

  5. On the density scaling of pVT data and transport properties for molecular and ionic liquids

    López, Enriqueta R.; Pensado, Alfonso S.; Fernández, Josefa; Harris, Kenneth R.

    2012-06-01

    In this work, a general equation of state (EOS) recently derived by Grzybowski et al. [Phys. Rev. E 83, 041505 (2011)] is applied to 51 molecular and ionic liquids in order to perform density scaling of pVT data employing the scaling exponent γEOS. It is found that the scaling is excellent in most cases examined. γEOS values range from 6.1 for ammonia to 13.3 for the ionic liquid [C4C1im][BF4]. These γEOS values are compared with results recently reported by us [E. R. López, A. S. Pensado, M. J. P. Comuñas, A. A. H. Pádua, J. Fernández, and K. R. Harris, J. Chem. Phys. 134, 144507 (2011)] for the scaling exponent γ obtained for several different transport properties, namely, the viscosity, self-diffusion coefficient, and electrical conductivity. For the majority of the compounds examined, γEOS > γ, but for hexane, heptane, octane, cyclopentane, cyclohexane, CCl4, dimethyl carbonate, m-xylene, and decalin, γEOS carbonate and 1-methylnaphthalene. Therefore, it seems the relation proposed by Paluch et al. applies only in certain cases, and is really not generally applicable to liquid transport properties such as viscosities, self-diffusion coefficients or electrical conductivities when examined over broad ranges of temperature and pressure.

  6. A review of the psychometric properties of the Health of the Nation Outcome Scales (HoNOS family of measures

    Dodson Sarity

    2005-11-01

    Full Text Available Abstract Background The Health of the Nation Outcome Scales was developed to routinely measure outcomes for adults with mental illness. Comparable instruments were also developed for children and adolescents (the Health of the Nation Outcome Scales for Children and Adolescents and older people (the Health of the Nation Outcome Scales 65+. All three are being widely used as outcome measures in the United Kingdom, Australia and New Zealand. There is, however, no comprehensive review of these instruments. This paper fills this gap by reviewing the psychometric properties of each. Method Articles and reports relating to the instruments were retrieved, and their findings synthesised to assess the instruments' validity (content, construct, concurrent, predictive, reliability (test-retest, inter-rater, sensitivity to change, and feasibility/utility. Results Mostly, the instruments perform adequately or better on most dimensions, although some of their psychometric properties warrant closer examination. Conclusion Collectively, the Health of the Nation Outcome Scales family of measures can assess outcomes for different groups on a range of mental health-related constructs, and can be regarded as appropriate for routinely monitoring outcomes.

  7. Examining the psychometric properties of the Barratt Impulsiveness Scale-Brief Form in justice-involved samples.

    Fields, Sherecce; Edens, John F; Smith, Shannon Toney; Rulseh, Allison; Donnellan, M Brent; Ruiz, Mark A; McDermott, Barbara E; Douglas, Kevin S

    2015-12-01

    Impulsivity is an important component of many forms of psychopathology. Though widely used as an index of this construct, the 30-item Barratt Impulsiveness Scale-11 (BIS-11) has demonstrated questionable psychometric properties in several research reports. An 8-item shortened version has recently been proposed, the Barratt Impulsiveness Scale-Brief (BIS-Brief) form, which was designed to overcome some of the limitations of the longer scale. In this report, we examine the internal structure and theoretically relevant external correlates of this new short form in large archival samples of individuals involved in the criminal justice system (prison inmates, substance abusers in mandatory treatment, and forensic inpatients). Confirmatory factor analysis of the BIS-Brief indicates adequate fit following a relatively minor modification. Correlations between the BIS-Brief and an array of criterion measures-other self-report scales, interview-based measures, and behavioral outcomes-are consistent with predictions and show relatively little or no decrement in predictive validity when compared with the 30-item BIS-11. Our results suggest that the BIS-Brief is a promising brief measure of impulsivity that evinces good psychometric properties across a range of offender samples. PMID:25894703

  8. Properties of the patient administered questionnaires: new scales measuring physical and psychological symptoms of hip and knee disorders.

    Mancuso, Carol A; Ranawat, Amar S; Meftah, Morteza; Koob, Trevor W; Ranawat, Chitranjan S

    2012-04-01

    The Patient Administered Questionnaires (PAQ) incorporate physical and psychological symptoms into one scale and permit more comprehensive self-reports for hip and knee disorders. We tested the psychometric properties of the PAQ-Hip and PAQ-Knee. Correlations between baseline PAQ-Hip and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were .39 to .72 (n = 102), .39 to .69 for score change (n = 68 post-total hip arthroplasty), and most κ values > .60 (n = 50). Correlations between baseline PAQ-Knee and WOMAC were .35 to .64 (n = 100), .62 to .79 for score change (n = 43 post-total knee arthroplasty), and most κ values >.60 (n = 51). For both scales, effect sizes were higher than for the WOMAC, and there was modest correlation between physical and psychological questions, indicating these concepts are not completely interchangeable. Thus, the PAQ scales have strong psychometric properties and are unique compared with existing scales by including physical and psychological symptoms. PMID:21945079

  9. Nursing students' attitudes toward mental health nursing and consumers: psychometric properties of a self-report scale.

    Hayman-White, Karla; Happell, Brenda

    2005-08-01

    There is a paucity of measures suitable for assessing the impact of educational and clinical placement strategies on nursing students' career preferences and attitudes toward mental health nursing and consumers of mental health services. Information derived from such scales could be used to improve existing recruitment strategies to this specialty area and identify misperceptions held by individuals joining the health care workforce. This article details the psychometric properties of a self-report scale designed to assess (1) preparedness for the mental health field, (2) attitudes toward mental illness and consumers of mental health services, and (3) attitudes toward mental health nursing, including career preferences. Results are based on data from a large Victorian study that explored the attitudes of 802 nursing students before their clinical placement in the mental health field. Principal components analysis with oblique rotation was used to identify the number and composition of components composing the newly developed scale. Results indicated seven components composed of relatively homogenous items; most items were good to excellent measures of each component. Cronbach alpha values indicated acceptable internal consistency of items composing four of the suggested components. Overall, findings indicated that the self-report scale is a useful instrument with acceptable psychometric properties. Descriptive and correlational analyses emphasized the importance of educational preparation preplacement and highlighted the potential for educational strategies to improve recruitment via improved attitudes and preparedness. PMID:16088857

  10. Design and psychometric properties of The Sexual Machism Scale (EMS-Sexism-12

    Cecilia Díaz Rodríguez

    2013-08-01

    Full Text Available The Sexual Machism Scale (EMS-Sexismo-12 evaluates in both men and women, sexism levels that could result in sexual health risk behaviors. Nowadays there is no Sexual Machism Scale. The analyses were made with 79 participants, 43 men and 36 women, with ages that go from 11 to 76 years. Originally 24 items were elaborated, however exploratory and confirmatory factor analysis guided the reduction of the scale. It is achieved to obtain a brief and precise scale (12 items, 0.91 alpha with only one factor that explains 98.1% of its variance and adequate goodness of fit indices in confirmatory factor analysis. We also analyzed differences between men and women founding higher scores in men than in women.

  11. Constraints on dark-matter properties from large-scale structure

    Kunz, Martin; Nesseris, Savvas; Sawicki, Ignacy

    2016-01-01

    We use large-scale cosmological observations to place constraints on the dark matter pressure, sound speed and viscosity, and infer a limit on the mass of warm dark matter particles. Measurements of the cosmic microwave background (CMB) anisotropies constrain the equation of state and sound speed of the dark matter at last scattering at the per mille level. Since the redshifting of collisionless particles universally implies that these quantities scale like $a^{-2}$ absent shell crossing, we ...

  12. Psychometric properties of fatigue severity and fatigue impact scales in postpolio patients.

    Oncu, Julide; Atamaz, Funda; Durmaz, Berrin; On, Arzu

    2013-12-01

    We evaluate the reliability, validity, and responsiveness of the Fatigue Severity Scale (FSS) and the Fatigue Impact Scale (FIS) and to determine whether these scales are potentially applicable for measuring fatigue in postpolio patients (PPS). After the Turkish adaptation of FSS and FIS using a forward-backward procedure, the scales were administered to 48 PPS patients without additional health problems that may induce fatigue. Reliability studies were carried out by determination of intraclass correlation coefficient and internal consistency by the Cronbach-α coefficient. Validity was tested by within-scale analyses and analyses against the external criteria including convergent validity and discriminant validity. Correlations with the Notthingham Health Profile (NHP), fatigue, pain and cramp severity (visual analog scale), and manual muscle testing were performed. Sensitivity to changes was determined by standardized response mean values. All patients completed scales, suggesting their satisfactory acceptance. Reliability studies were satisfactory, with higher Cronbach-α values and intraclass correlation coefficients than 0.80. The FSS score was correlated moderately with visual analog scale-fatigue (r=0.41) and the NHP-energy dimension (r=0.29). All FIS scores except cognitive scores were moderately related to the NHP-social isolation score (r=0.40, 0.37, and 0.43 for FIS-physical, social, and total scores, respectively). There was also a significant correlation between the FIS-physical score and the NHP-energy score (r=0.31). On the basis of the standardized response mean values, response to treatment for these two questionnaires was satisfactory (P=0.00). The Turkish versions of FSS and FIS were reliable, sensitive to clinical changes, and also well accepted by patients with PPS. Although they had somewhat satisfactory convergent validity, the absence of strong correlations did not support the validity entirely. PMID:23903028

  13. Small-scale structure formation properties of chilled sterile neutrinos as dark matter

    Petraki, Kalliopi

    2008-01-01

    We calculate the free-streaming length and the phase space density of dark-matter sterile neutrinos produced from decays, at the electroweak scale, of a gauge singlet in the Higgs sector. These quantities, which depend on the dark-matter production mechanism, are relevant to the study of small-scale structure formation and may be used to constrain or rule out dark-matter candidates.

  14. Psychometric properties of the HIV/ AIDS Knowledge Scale for Spanish adolescents (HIV-KS)

    Espada Sánchez, José Pedro; Huedo Medina, Tania B.; Orgilés Amorós, Mireia; Secades Villa, Roberto; Ballester Arnal, Rafael; Remor Bitencourt, Eduardo

    2009-01-01

    This paper aims to describe the development process, the factor structure, the reliability and validity of a multidimensional scale to measure HIV/AIDS-related knowledge for adolescents (HIV/AIDS Knowledge Scale, HIV-KS). After a pilot study of the items, a questionnaire of 28 items was administered to a sample from 14 different schools in 5 counties in Spain. Firstly, Principal-component analysis was used: first, to test a theory-driven structure and second, to develop an e...

  15. Psychometric Properties of the Self-Assessment of Nursing Informatics Competencies Scale

    Yoon, Sunmoo; Yen, Po-Yin; Bakken, Suzanne

    2009-01-01

    The objective of this study was to examine the factor structure, internal consistency reliability, and responsiveness of the Self-Assessment of Nursing Informatics Competencies Scale (SANICS). Combined BS/MS nursing students (N=336) completed the 93-item scale, which was based upon published and locally-developed nursing informatics competency statements. Exploratory principal component analysis with oblique promax rotation extracted five factors comprising 30 items that explained 63.7% of th...

  16. Psychometric Properties of the “Sport Motivation Scale (SMS)” Adapted to Physical Education

    Antonio Granero-Gallegos, Antonio Baena-Extremera; Manuel Gómez-López, José Antonio Sánchez-Fuentes, J. Arturo Abraldes

    2014-01-01

    The aim of this study was to investigate the factor structure of a Spanish version of the Sport Motivation Scale adapted to physical education. A second aim was to test which one of three hypothesized models (three, five and seven-factor) provided best model fit. 758 Spanish high school students completed the Sport Motivation Scale adapted for Physical Education and also completed the Learning and Performance Orientation in Physical Education Classes Questionnaire. We examined the factor stru...

  17. Psychometric properties of the Thai version of the Diabetes Distress Scale in diabetic seniors

    Thanakwang K; Thinganjana W; Konggumnerd R

    2014-01-01

    Kattika Thanakwang, Wantana Thinganjana, Roumporn Konggumnerd Institute of Nursing, Suranaree University of Technology, Nakhon Ratchasima, Thailand Background: The Diabetes Distress Scale (DDS) is an important measure of diabetes-related emotional distress that has been widely used in the Western world. In Thailand, there is a lack of reliable and valid scales for assessing distress levels in diabetes patients, specifically in older adults.Objectives: The main objectives of this study were ...

  18. Voxel Scale Complex Networks of Functional Connectivity in the Rat Brain: Neurochemical State Dependence of Global and Local Topological Properties

    Adam J. Schwarz

    2012-01-01

    Full Text Available Network analysis of functional imaging data reveals emergent features of the brain as a function of its topological properties. However, the brain is not a homogeneous network, and the dependence of functional connectivity parameters on neuroanatomical substrate and parcellation scale is a key issue. Moreover, the extent to which these topological properties depend on underlying neurochemical changes remains unclear. In the present study, we investigated both global statistical properties and the local, voxel-scale distribution of connectivity parameters of the rat brain. Different neurotransmitter systems were stimulated by pharmacological challenge (d-amphetamine, fluoxetine, and nicotine to discriminate between stimulus-specific functional connectivity and more general features of the rat brain architecture. Although global connectivity parameters were similar, mapping of local connectivity parameters at high spatial resolution revealed strong neuroanatomical dependence of functional connectivity in the rat brain, with clear differentiation between the neocortex and older brain regions. Localized foci of high functional connectivity independent of drug challenge were found in the sensorimotor cortices, consistent with the high neuronal connectivity in these regions. Conversely, the topological properties and node roles in subcortical regions varied with neurochemical state and were dependent on the specific dynamics of the different functional processes elicited.

  19. USE OF SCALED SEMIVARIOGRAMS IN THE PLANNING SAMPLE OF SOIL CHEMICAL PROPERTIES IN SOUTHERN AMAZONAS, BRAZIL

    Ivanildo Amorim de Oliveira

    2015-02-01

    Full Text Available The lack of information concerning the variability of soil properties has been a major concern of researchers in the Amazon region. Thus, the aim of this study was to evaluate the spatial variability of soil chemical properties and determine minimal sampling density to characterize the variability of these properties in five environments located in the south of the State of Amazonas, Brazil. The five environments were archaeological dark earth (ADE, forest, pasture land, agroforestry operation, and sugarcane crop. Regular 70 × 70 m mesh grids were set up in these areas, with 64 sample points spaced at 10 m distance. Soil samples were collected at the 0.0-0.1 m depth. The chemical properties of pH in water, OM, P, K, Ca, Mg, H+Al, SB, CEC, and V were determined at these points. Data were analyzed by descriptive and geostatistical analyses. A large part of the data analyzed showed spatial dependence. Chemical properties were best fitted to the spherical model in almost all the environments evaluated, except for the sugarcane field with a better fit to the exponential model. ADE and sugarcane areas had greater heterogeneity of soil chemical properties, showing a greater range and higher sampling density; however, forest and agroforestry areas had less variability of chemical properties.

  20. Characterization of scale-free properties of human electrocorticography in awake and slow wave sleep states

    John M Zempel

    2012-06-01

    Full Text Available Like many complex dynamic systems, the brain exhibits scale-free dynamics that follow power law scaling. Broadband power spectral density (PSD of brain electrical activity exhibits state-dependent power law scaling with a log frequency exponent that varies across frequency ranges. Widely divergent naturally occurring neural states, awake and slow wave sleep (SWS periods, were used evaluate the nature of changes in scale-free indices. We demonstrate two analytic approaches to characterizing electrocorticographic (ECoG data obtained during Awake and SWS states. A data driven approach was used, characterizing all available frequency ranges. Using an Equal Error State Discriminator (EESD, a single frequency range did not best characterize state across data from all six subjects, though the ability to distinguish awake and SWS states in individual subjects was excellent. Multisegment piecewise linear fits were used to characterize scale-free slopes across the entire frequency range (0.2-200 Hz. These scale-free slopes differed between Awake and SWS states across subjects, particularly at frequencies below 10 Hz and showed little difference at frequencies above 70 Hz. A Multivariate Maximum Likelihood Analysis (MMLA method using the multisegment slope indices successfully categorized ECoG data in most subjects, though individual variation was seen. The ECoG spectrum is not well characterized by a single linear fit across a defined set of frequencies, but is best described by a set of discrete linear fits across the full range of available frequencies. With increasing computational tractability, the use of scale-free slope values to characterize EEG data will have practical value in clinical and research EEG studies.

  1. Psychometric properties of the Greek version of the Social Constraints Scale in a sample of women with breast cancer.

    Koutrouli, Natalia; Anagnostopoulos, Fotios; Tsikkinis, Annivas; Papastylianou, Dona; Lepore, Stephen

    2016-01-01

    This study evaluated the psychometric properties of the Greek version of the Social Constraints Scale, developed in English by Lepore and Ituarte (1999). The scale was culturally adapted in Greek and was then administered, along with measures of psychological distress and intrusions, to a sample of 202 women with breast cancer, recruited from July 2012 to October 2013. Although the scale has usually been treated as a unidimensional measure, exploratory factor analysis revealed three underlying factors in the Greek Social Constraints Scale: unsupportive behaviors, avoidant behaviors, and suggestions for pretense and distraction. The three-factor solution explained 55% of the total variance. Subscale reliability was satisfactory (Cronbach's alpha coefficients ranging from 0.77 to 0.88). All subscales were significantly related to intrusions and psychological distress. Thus, the Greek Social Constraints Scale is a reliable and valid multidimensional instrument. The results of the present study show that, among all kinds of social constraints, unsupportive behaviors are the most highly correlated with distress, while distraction/pretense is most correlated with intrusiveness. Findings suggested that health professionals should aim to educate both the patient to claim her right to express feelings and thoughts and her social network to adopt disclosure-facilitating behaviors to compensate for intrusiveness and distress. PMID:26496047

  2. Bio-inspired scale-like surface textures and their tribological properties.

    Greiner, Christian; Schäfer, Michael

    2015-08-01

    Friction, wear and the associated energy dissipation are major challenges in all systems containing moving parts. Examples range from nanoelectromechanical systems over hip prosthesis to off-shore wind turbines. Bionic approaches have proven to be very successful in many engineering problems, while investigating the potential of a bio-inspired approach in creating morphological surface textures is a relatively new field of research. Here, we developed laser-created textures inspired by the scales found on the skin of snakes and certain lizards. We show that this bio-inspired surface morphology reduced dry sliding friction forces by more than 40%. In lubricated contacts the same morphology increased friction by a factor of three. Two different kinds of morphologies, one with completely overlapping scales and one with the scales arranged in individual rows, were chosen. In lubricated as well as unlubricated contacts, the surface texture with the scales in rows showed lower friction forces than the completely overlapping ones. We anticipate that these results could have significant impact in all dry sliding contacts, ranging from nanoelectromechanical and micro-positioning systems up to large-scale tribological contacts which cannot be lubricated, e.g. because they are employed in a vacuum environment. PMID:26125522

  3. Scaling Properties of a Complete X-ray Selected Galaxy Group Sample

    Lovisari, Lorenzo; Reiprich, Thomas; Schellenberger, Gerrit

    2014-01-01

    Upcoming X-ray surveys like eROSITA require precise calibration between X-ray observables and mass down to the low mass regime to set tight constraints on the fundamental cosmological parameters. Since an individual mass measurement is only possible for a relatively small number of objects it is crucial to have robust and well understood scaling relations that relate the total mass to easily observable quantities. The main goal of this work is to constrain the galaxy group scaling relations c...

  4. Index Grids, Property Map Index for Tax Maps. 1"=600' grid and larger scale insert grids for selected counties., Published in 2010, 1:7200 (1in=600ft) scale, Maryland Department of Planning.

    NSGIC GIS Inventory (aka Ramona) — This Index Grids dataset, published at 1:7200 (1in=600ft) scale, was produced all or in part from Hardcopy Maps information as of 2010. It is described as 'Property...

  5. Petrophysical analysis of regional-scale thermal properties for improved simulations of geothermal installations and basin-scale heat and fluid flow

    Hartmann, Andreas; Clauser, Christoph

    2008-01-01

    Development of geothermal energy and basin-scale simulations of fluid and heat flow both suffer from uncertain physical rock properties at depth. Therefore, building better prognostic models are required. We analysed hydraulic and thermal properties of the major rock types in the Molasse Basin in Southern Germany. On about 400 samples thermal conductivity, density, porosity, and sonic velocity were measured. Here, we propose a three-step procedure with increasing complexity for analysis of the data set: First, univariate descriptive statistics provides a general understanding of the data structure, possibly still with large uncertainty. Examples show that the remaining uncertainty can be as high as 0.8 W/(m K) or as low as 0.1 W/(m K). This depends on the possibility to subdivide the geologic units into data sets that are also petrophysically similar. Then, based on all measurements, cross-plot and quick-look methods are used to gain more insight into petrophysical relationships and to refine the analysis. Be...

  6. Evaluation of properties of the Vestibular Disorders Activities of Daily Living Scale (Brazilian version in an elderly population

    Natalia A. Ricci

    2014-05-01

    Full Text Available Background: The Vestibular Disorders Activities of Daily Living Scale (VADL is considered an important subjective assessment to evaluate patients suffering from dizziness and imbalance. Although frequently used, its metric characteristics still require further investigation. Objective: This paper aims to analyze the psychometric properties of the Brazilian version of the VADL in an elderly population. Method: The sample comprises patients (≥65 years old with chronic dizziness resulting from vestibular disorders. For discriminant analysis, patients were compared to healthy subjects. All subjects answered the VADL-Brazil by interview. To examine the VADL validity, patients filled out the Dizziness Handicap Inventory (DHI and the ABC scale and were tested on the Dynamic Gait Index (DGI. To evaluate the VADL responsiveness, 20 patients were submitted to rehabilitation. Results: Patients (n=140 had a VADL total score of 4.1±1.6 points. Healthy subjects scored significantly less than patients in all the subscales and in the VADL total score. The VADL-Brazil was weakly correlated with the DHI and moderately to the ABC scale and the DGI. Instead of the original 3 subscales, factor analysis resulted in 6 factors. The VADL was capable of detecting changes after rehabilitation, which means that the instrument has responsiveness. Conclusions: This study provided more data about the psychometric properties and usefulness of the VADL-Brazil. The use of such a reliable and valid instrument increases the knowledge about disability in patients with vestibular disorders.

  7. Measuring workplace trauma response in Australian paramedics: an investigation into the psychometric properties of the Impact of Event Scale

    Hogan N

    2015-12-01

    Full Text Available Nicola Hogan,1 Shane Costello,1 Malcolm Boyle,2 Brett Williams2 1Faculty of Education, Monash University, Clayton, VIC, Australia; 2Department of Community Emergency Health and Paramedic Practice, Monash University, Frankston, VIC, Australia Introduction: Investigation into the psychological effects of violence toward health care workers and its associated trauma is increasing. The Impact of Event Scale (IES provides a measure of current, subjective, emotional distress symptomatic of a specific traumatic event. However, its validity among paramedics is largely unknown. Problem: The purpose of this study was to investigate the psychometric properties and factor structure of the IES with a sample of Australian paramedics. Methods: The study aimed to investigate the psychometric properties and factor structure of the 15-item IES with a sample of Australian paramedics using Exploratory Factor Analysis with model fit statistics as found in confirmatory analysis. Results: Maximum Likelihood Factor Analysis with Varimax rotation supported the hypothesis that a two-factor solution would provide the best fit of the data. Procrustes rotation provided further support for this hypothesis indicating that the factors, labeled “Intrusion” and “Avoidance”, as well as the individual items of the 12-item final model, were a good fit to an ideal solution. Conclusion: The revision of the scale has improved its validity for use in the general population of paramedics, improving the potential for its use in trauma-related research. Keywords: impact of event scale, psychometrics, paramedics, occupational violence, PTSD

  8. Examining the Psychometric Properties of the Homework Management Scale for High School Students in China

    Yang, Fuyi; Xu, Jianzhong

    2015-01-01

    This study reports on the psychometric evaluation of the Chinese version of the Homework Management Scale (HMS). The HMS was designed to assess students' homework management strategies. Based on a randomized split of 884 high school students in China, we conducted exploratory factor analysis on Group 1 (n = 442) and confirmatory factor analysis on…

  9. Psychometric properties and clinical relevance of the Adolescent Sleep Hygiene Scale in Dutch adolescents

    E.J. de Bruin; R.K.A. van Kampen; T. van Kooten; A.M. Meijer

    2014-01-01

    Objective: This study investigated reliability, validity, and clinical relevance of the Adolescent Sleep Hygiene Scale (ASHS) in Dutch adolescents. Methods: The Dutch translation of the ASHS was administered to 186 normal-sleeping adolescents and 112 adolescents with insomnia. Their sleep variables

  10. The Child PTSD Symptom Scale: Psychometric Properties in Female Adolescent Sexual Assault Survivors

    Gillihan, Seth J.; Aderka, Idan M.; Conklin, Phoebe H.; Capaldi, Sandra; Foa, Edna B.

    2013-01-01

    Traumatic experiences are common among youths and can lead to posttraumatic stress disorder (PTSD). In order to identify traumatized children who need PTSD treatment, instruments that can accurately and efficiently evaluate pediatric PTSD are needed. One such measure is the Child PTSD Symptom Scale (CPSS), which has been found to be a reliable and…

  11. Scaling properties of inclusive W{sup ±} production at hadron colliders

    Arleo, Francois; Chapon, Emilien [Ecole polytechnique, CNRS/IN2P3, Universite Paris-Saclay, Laboratoire Leprince-Ringuet, Palaiseau (France); Paukkunen, Hannu [University of Jyvaskyla, Department of Physics, P.O. Box 35, University of Jyvaskyla (Finland); Helsinki Institute of Physics, P.O. Box 64, University of Helsinki (Finland); Universidade de Santiago de Compostela, Departamento de Fisica de Particulas and IGFAE, Santiago de Compostela, Galicia (Spain)

    2016-04-15

    We consider the hadroproduction of W gauge bosons in their leptonic decay mode. Starting from the leading-order expressions, we show that by defining a suitable scaling variable the centre-of-mass dependence of the cross sections at the LHC energies can be essentially described by a simple power law. The scaling exponent is directly linked to the small-x behaviour of parton distribution functions (PDF) which, at the high virtualities involved in W production, is largely dictated by QCD evolution equations. This entails a particularly simple scaling law for the lepton charge asymmetry and also predicts that measurements in different collision systems (p-p, p-p, p-Pb Pb-Pb) are straightforwardly related. The expectations are compared with the existing data and a very good overall agreement is observed. It is shown that the PDF uncertainty in certain cross-section ratios between nearby centre-of-mass energies can be significantly reduced by taking the ratios at fixed value of the scaling variable instead of fixed rapidity. (orig.)

  12. Noise sensitivity and multiple chemical sensitivity scales: Properties in a population based epidemiological study

    Marja Heinonen-Guzejev

    2012-01-01

    Full Text Available Noise sensitivity is considered to be a self-perceived indicator of vulnerability to stressors in general and not noise alone. Multiple chemical sensitivity (MCS has to some extent been accompanied by noise sensitivity, indicating a moderate correspondence between them. The aim of this study is to investigate if the Weinstein′s Noise Sensitivity Scale and Quick Environmental Exposure and Sensitivity Inventory′s (QEESI Chemical Intolerance Subscale can differentiate noise sensitivity and MCS as different entities, and if there are overlaps in the characteristics of noise sensitivity and MCS. In 2002, 327 individuals (166 men, 161 women; age range 45 - 66 years from the Finnish Twin Cohort answered a questionnaire on noise-related and MCS items. Somatic, psychological, and lifestyle factors were obtained through earlier questionnaires for the same individuals. Both confirmatory and exploratory factor analyses (CFA and EFA of the questionnaire items on the Weinstein′s Noise Sensitivity Scale and QEESI′s Chemical Intolerance Subscale indicated the presence of three factors - Noise Sensitivity, Chemical Sensitivity, and Ability to Concentrate factors - arising from the forming of two factors from the items of the Weinstein′s scale. In the regression analyses, among all subjects, the Noise Sensitivity Factor was associated with neuroticism and smoking, and the Chemical Sensitivity Factor was associated with allergies and alcohol use. The study indicates that the Weinstein′s Noise Sensitivity Scale and QEESI′s Chemical Intolerance Subscale differentiate noise sensitivity and MCS as different entities.

  13. Sum rules study and a scaling property of fragmentation mass yield curves

    Information obtained in mass yield distributions produced in protons and heavy ions induced reactions has been analyzed with two model independent sum rules. The average number of fragments of different sizes produced in one collision has been extracted. A scaling law for the mass yield has been deduced. (orig.)

  14. Small-scale structure formation properties of chilled sterile neutrinos as dark matter

    Petraki, Kalliopi

    2008-01-01

    We calculate the free-streaming length and the phase space density of dark-matter sterile neutrinos produced from decays of a gauge singlet in the Higgs sector. These quantities, which depend on the dark matter production mechanism, are relevant to the study of small-scale structure formation and may be used to constrain or rule out dark matter candidates.

  15. Psychometric Properties of a Portuguese Version of the Subjective Happiness Scale

    Spagnoli, Paola; Caetano, Antonio; Silva, Ana

    2012-01-01

    The Subjective Happiness Scale (SHS) constitutes an instrument for assessing subjective happiness. This study aims to present the validation of the SHS in a Portuguese adult population. A large representative sample (1,017 participants), from five different age groups was considered. Configurational invariance of the unidimensional structure of…

  16. On the properties of slow mhd sausage waves within small-scale photospheric magnetic structures

    Freij, N; Morton, R J; Ruderman, M S; Karlovsky, V; Erdekyi, R

    2015-01-01

    The presence of magneto-acoustic waves in magnetic structures in the solar atmosphere is well-documented. Applying the technique of solar magneto-seismology (SMS) allows us to infer the background properties of these structures. Here, we aim to identify properties of the observed magneto-acoustic waves and study the background properties of magnetic structures within the lower solar atmosphere. Using the Dutch Open Telescope (DOT) and Rapid Oscillations in the Solar Atmosphere (ROSA) instruments, we captured two series of high-resolution intensity images with short cadence of two isolated magnetic pores. Combining wavelet analysis and empirical mode decomposition (EMD), we determined characteristic periods within the cross-sectional (i.e., area) and intensity time series. Then, by applying the theory of linear magnetohydrodynamics (MHD), we identified the mode of these oscillations within the MHD framework. Several oscillations have been detected within these two magnetic pores. Their periods range from 3 to ...

  17. The psychometric properties of the Turkish Stroke and Aphasia Quality Of Life Scale-39.

    Atamaz Calis, Funda; Celik, Serpil; Demir, Orcun; Aykanat, Dilek; Yagiz On, Arzu

    2016-06-01

    The Stroke and Aphasia Quality Of Life Scale (SAQOL-39) is a widely used instrument in assessing the quality of life in aphasic patients. Our purpose was to translate the SAQOL-39 into the Turkish language (SAQOL-39/TR) and assess its reliability and validity in patients who had aphasia. SAQOL-39/TR was obtained using the 'translation-backward translation' method and administered to 40 patients with aphasia. The reliability studies were performed by means of internal consistency and test-retest reliability. The validation studies were carried out by means of construct validity using within-scale analyses and analyses against the external criteria. Correlation analysis was performed between scales and the Ege Aphasia Test, the Barthel index, the 12-item General Health Questionnaire and the Brunnstrom recovery stages (BRS) of the arm, hand, and lower extremity. In the results, the scores of the SAQOL-39 were not different between groups. Cronbach's α variables were good for all domains (0.80, 0.88, 0.89, 0.82, and 0.83). Test-retest reliability was also high (0.96, 0.97, 0.91, 0.70, and 0.96). There were significant correlations with coefficients ranging from 0.36 to 0.60 among the domains of scale and other measures. Moderate-high correlations were also seen with BRS-arm, BRS-hand, and BRS-lower extremity (r, 0.27-0.58). It was found that all domains were highly related with all domains of Ege aphasia test, except praxia (P<0.001). This study showed that the SAQOL-39/TR has acceptable validity and reliability in assessing the quality of life. However, similar results of the scale in patients with dysarthria suggest that the SAQOL-39 may not be specific to only aphasic patients. PMID:26954990

  18. Scaling properties at freeze-out in relativistic heavy-ion collisions

    Aggarwal, M. M.; Ahammed, Z.; Braidot, E.; Peitzmann, T.(Institute for Subatomic Physics of Utrecht University, Utrecht, Netherlands); van Leeuwen, M.(Institute for Subatomic Physics of Utrecht University, Utrecht, Netherlands); Zoulkarneeva, Y.

    2011-01-01

    Identified charged pion, kaon, and proton spectra are used to explore the system size dependence of bulk freeze-out properties in Cu+Cu collisions at √sNN=200 and 62.4 GeV. The data are studied with hydrodynamically motivated blast-wave and statistical model frameworks in order to characterize the freeze-out properties of the system. The dependence of freeze-out parameters on beam energy and collision centrality is discussed. Using the existing results from Au + Au and pp collisions, the depe...

  19. The SCI Exercise Self-Efficacy Scale (ESES: development and psychometric properties

    Ho Pei-Shu

    2007-08-01

    Full Text Available Abstract Background Rising prevalence of secondary conditions among persons with spinal cord injury (SCI has focused recent attention to potential health promotion programs designed to reduce such adverse health conditions. A healthy lifestyle for people with SCI, including and specifically, the adoption of a vigorous exercise routine, has been shown to produce an array of health benefits, prompting many providers to recommend the implementation of such activity to those with SCI. Successfully adopting such an exercise regimen however, requires confidence in one's ability to engage in exercise or exercise self-efficacy. Exercise self-efficacy has not been assessed adequately for people with SCI due to a lack of validated and reliable scales, despite self efficacy's status as one of the most widely researched concepts and despite its broad application in health promotion studies. Exercise self efficacy supporting interventions for people with SCI are only meaningful if appropriate measurement tools exist. The objective of our study was to develop a psychometrically sound exercise self-efficacy self-report measure for people with SCI. Methods Based on literature reviews, expert comments and cognitive testing, 10 items were included and made up the 4-point Likert SCI Exercise Self-Efficacy Scale (ESES in its current form. The ESES was administered as part of the first wave of a nationwide survey (n = 368 on exercise behavior and was also tested separately for validity in four groups of individuals with SCI. Reliability and validity testing was performed using SPSS 12.0. Results Cronbach's alpha was .9269 for the ESES. High internal consistency was confirmed in split-half (EQ Length Spearman Brown = .8836. Construct validity was determined using principal component factor analysis by correlating the aggregated ESES items with the Generalised Self Efficacy Scale (GSE. We found that all items loaded on one factor only and that there was a

  20. Large Scale FEM of the effective elastic properties of particle reinforced composites

    Rauhe, Jens Christian; Pyrz, Ryszard; Lund, Erik

    2004-01-01

    Over the years several methods have been proposed for the determination of the effective elastic properties of particle reinforced composites. The material microstructures used in the present analysis is a real microstructure and a numerically generated microstructure. X-ray microtomography is us...

  1. Individual differences on social comparison : properties of the orientation Spanish scale towards social comparison

    Buunk, AP; Belmonte, J; Peiro, JM; Zurriaga, R; Gibbons, FX

    2005-01-01

    This paper describes the development and the properties of the INCOM-E, the Spanish language version of the INCOM, a measure to assess individual differences in social comparison orientation that was originally developed simultaneously in English and in Dutch. In both Study 1 (including 212 students

  2. A validation study of the psychometric properties of the Groningen Reflection Ability Scale

    Andersen, Nina Bjerre; O'Neill, Lotte; Gormsen, Lise Kirstine;

    2014-01-01

    . The aim of this study was to adapt GRAS for use in a Danish setting and to investigate the psychometric properties of GRAS-DK. Methods We performed a cross-cultural adaptation of GRAS from Dutch to Danish. Next, we collected primary data online, performed a retest, analysed data descriptively...

  3. The Noval Properties and Construction of Multi-scale Matrix-valued Bivariate Wavelet wraps

    Zhang, Hai-mo

    In this paper, we introduce matrix-valued multi-resolution structure and matrix-valued bivariate wavelet wraps. A constructive method of semi-orthogonal matrix-valued bivari-ate wavelet wraps is presented. Their properties have been characterized by using time-frequency analysis method, unitary extension principle and operator theory. The direct decom-position relation is obtained.

  4. PSYCHOMETRIC PROPERTIES OF THE THREE PATHWAYS TO WELL-BEING SCALE IN A LARGE SAMPLE OF ARGENTINEAN ADOLESCENTS.

    Góngora, Vanesa C; Castro Solano, Alejandro

    2015-08-01

    The Authentic Happiness Theory considers that well-being can be reached by three main pathways: a pleasant life, an engaged life, or a meaningful life. This study investigates the psychometric properties of the Three Pathways to Well-being scale in Argentinean adolescents and compares that to prior results for Argentinean adults. A sample of 255 Argentinean adolescent students (110 boys, 145 girls) aged between 13 and 18 years (M age = 15.5, SD = 1.6) was used in this study. The participants completed the Spanish versions of the Three Pathways to Well-being scale, the Meaning in Life Questionnaire, the Satisfaction With Life Scale, and the Personal Wellbeing Index. Confirmatory factor analyses verified the three-factor structure of the test, accounting for 46% of the variance. The internal consistencies were α = .76 for the pleasant life, α = .80 for the engaged life, and α = .70 for the meaningful life. Concurrent validity was examined with the Satisfaction With Life Scale, the Personal Wellbeing Index, and the Meaning in Life Questionnaire, and the engaged life was the pathway most strongly associated with the positive related measures. PMID:26302293

  5. Brief version of the Fear of Negative Evaluation Scale - Straightforward Items (BFNE-S): psychometric properties in a Spanish population.

    Pitarch, María José Gallego

    2010-11-01

    The aim of this study was to examine the psychometric properties of the Brief version of the Fear of Negative Evaluation Scale - Straightforward Items (BFNE-S) in a non-clinical Spanish population. Rodebaugh et al. (2004) recommend the use of this scale composed of 8 straightforwardly-worded items, instead of the 12-item version of the BFNE. The sample consisted of 542 undergraduate students, 71.3% of whom were women and 28.7% were men; the mean age was 21.71 (4.78) years. Exploratory factor analysis produced one factor which accounted for 51.28% of variance. The internal consistency of the scale was alpha = .89. The BFNE-S correlated with the Social Avoidance and Distress Scale (r = .44), the Personal Report of Confidence as Speaker Modified (r = .44), the Public Speaking Self-Efficacy Questionnaire (r = -.38) and both subscales of the Self-Statements during Public Speaking (SSPS-P r = -.22; SSPS-N r = .53). ANOVAs revealed significant differences in the BFNE-S amongst a non-clinical population, persons suffering from specific social phobia, non-generalized social phobia and generalized social phobia. PMID:20977045

  6. Ion transport in porous media: derivation of the macroscopic equations using up-scaling and properties of the effective coefficients

    In this work, we undertake a numerical study of the effective coefficients arising in the up-scaling of a system of partial differential equations describing transport of a dilute N-component electrolyte in a Newtonian solvent through a rigid porous medium. The motion is governed by a small static electric field and a small hydrodynamic force, around a nonlinear Poisson-Boltzmann equilibrium with given surface charges of arbitrary size. This approach allows us to calculate the linear response regime in a way initially proposed by O'Brien. The O'Brien linearization requires a fast and accurate solution of the underlying Poisson-Boltzmann equation. We present an analysis of it, with the discussion of the boundary layer appearing as the Debye-Huckel parameter becomes large. Next, we briefly discuss the corresponding two-scale asymptotic expansion and reduce the obtained two-scale equations to a coarse scale model. Our previous rigorous study proves that the homogenized coefficients satisfy Onsager properties, namely they are symmetric positive definite tensors. We illustrate with numerical simulations several characteristic situations and discuss the behavior of the effective coefficients when the Debye-Huckel parameter is large. Simulated qualitative behavior differs significantly from the situation when the surface potential is given (instead of the surface charges). In particular, we observe the Donnan effect (exclusion of co-ions for small pores). (authors)

  7. Probing mechanical properties of thin film and ceramic materials in micro- and nano-scale using indentation techniques

    In this study, we report on the mechanical properties, failure and fracture modes in two cases of engineering materials; that is transparent silicon oxide thin films onto poly(ethylene terephthalate) (PET) membranes and glass-ceramic materials. The first system was studied by the quazi-static indentation technique at the nano-scale and the second by the static indentation technique at the micro-scale. Nanocomposite laminates of silicon oxide thin films onto PET were found to sustain higher scratch induced stresses and were effective as protective coating material for PET membranes. Glass-ceramic materials with separated crystallites of different morphologies sustained a mixed crack propagation pattern in brittle fracture mode.

  8. Scaling properties of net information measures for bound states of spherical model potentials confined with finite barrier

    S H Patil; K D Sen

    2012-01-01

    Using dimensional analyses, the scaling properties of the Heisenberg uncertainty relationship as well as the various information theoretical uncertainty-like relationships are derived for the bound states corresponding to the superposition of the power potential of the form () = + $^{n_{i}}, where , , , are parameters, in the free state as well as in the additional presence of a spherical penetrable boundary wall located at radius The uncertainty product and all other net information measures are shown here to depend only on the parameters [] defined by the ratios /$^{(n_{i}+2)/(n+2)}$. Introduction of a finite potential, V at the radial distance ≥ results in a complete set of scaling parameters given by [, 1, 2], where 1 is given by 1/(n+2) and 2 = V/()2/(+2).

  9. Probing mechanical properties of thin film and ceramic materials in micro- and nano-scale using indentation techniques

    Charitidis, Costas A., E-mail: charitidis@chemeng.ntua.gr [National Technical University of Athens, School of Chemical Engineering, 9 Heroon Polytechniou St., Zographos, Athens GR-157 80 (Greece)

    2010-10-01

    In this study, we report on the mechanical properties, failure and fracture modes in two cases of engineering materials; that is transparent silicon oxide thin films onto poly(ethylene terephthalate) (PET) membranes and glass-ceramic materials. The first system was studied by the quazi-static indentation technique at the nano-scale and the second by the static indentation technique at the micro-scale. Nanocomposite laminates of silicon oxide thin films onto PET were found to sustain higher scratch induced stresses and were effective as protective coating material for PET membranes. Glass-ceramic materials with separated crystallites of different morphologies sustained a mixed crack propagation pattern in brittle fracture mode.

  10. Design and properties of vector-valued wavelets associated with an orthogonal vector-valued scaling function

    The notion of vector-valued wavelets associated with an orthogonal vector-valued scaling function with 3-scale is introduced. The existence of orthogonal vector-valued wavelets is discussed and a necessary and sufficient condition is presented by means of the theory of vector-valued multiresolution analysis and paraunitary vector filter bank theory. An algorithm for constructing a class of orthogonal vector-valued wavelets with compact support is proposed. The concept of vector-valued wavelet packets is introduced and their properties are characterized by virtue of operator theory, time-frequency analysis method. Moreover, it is shown how to construct various orthonormal bases of space L2(R,Cμ)(2≤μ element of Z) from these wavelet packets. Relation to some physical theories such as fractal theory and E-infinity theory is also discussed.

  11. AMiBA: Sunyaev-Zel'Dovich Effect-derived Properties and Scaling Relations of Massive Galaxy Clusters

    Liao, Yu-Wei; Proty Wu, Jiun-Huei; Ho, Paul T. P.; Locutus Huang, Chih-Wei; Koch, Patrick M.; Lin, Kai-Yang; Liu, Guo-Chin; Molnar, Sandor M.; Nishioka, Hiroaki; Umetsu, Keiichi; Wang, Fu-Cheng; Altamirano, Pablo; Birkinshaw, Mark; Chang, Chia-Hao; Chang, Shu-Hao; Chang, Su-Wei; Chen, Ming-Tang; Chiueh, Tzihong; Han, Chih-Chiang; Huang, Yau-De; Hwang, Yuh-Jing; Jiang, Homin; Kesteven, Michael; Kubo, Derek Y.; Li, Chao-Te; Martin-Cocher, Pierre; Oshiro, Peter; Raffin, Philippe; Wei, Tashun; Wilson, Warwick

    2010-04-01

    The Sunyaev-Zel'dovich Effect (SZE) has been observed toward six massive galaxy clusters, at redshifts 0.091 AMiBA). We modify an iterative method, based on the isothermal β models, to derive the electron temperature T e, total mass M t, gas mass M g, and integrated Compton Y within r 2500, from the AMiBA SZE data. Non-isothermal universal temperature profile (UTP) β models are also considered in this paper. These results are in good agreement with those deduced from other observations. We also investigate the embedded scaling relations, due to the assumptions that have been made in the method we adopted, between these purely SZE-deduced T e, M t, M g, and Y. Our results suggest that cluster properties may be measurable with SZE observations alone. However, the assumptions built into the pure-SZE method bias the results of scaling relation estimations and need further study.

  12. A multi-scale approach of mechanical and transport properties of cementitious materials under rises of temperature

    The modern industrial activities (storage of nuclear waste, geothermal wells, nuclear power plants,...) can submit cementitious materials to some extreme conditions, for example at temperatures above 200 C. This level of temperature will induce phenomena of dehydration in the cement paste, particularly impacting the CSH hydrates which led to the mechanical cohesion. The effects of these temperatures on the mechanical and transport properties have been the subject of this thesis.To understand these effects, we need to take into account the heterogeneous, porous, multi-scale aspects of these materials. To do this, micro-mechanics and homogenization tools based on the Eshelby problem's solution were used. Moreover, to support this multi-scale modeling, mechanical testing based on the theory of porous media were conducted. The measurements of modulus compressibility, permeability and porosity under confining pressure were used to investigate the mechanisms of degradation of these materials during thermal loads up to 400 C. (author)

  13. Scaling Properties of Hyperon Production in Au+Au Collisions at sqrt(s_NN) = 200 GeV

    Adams, J; Ahammed, Z; Amonett, J; Anderson, B D; Anderson, M; Arkhipkin, D; Averichev, G S; Bai, Y; Balewski, J; Barannikova, O; Barnby, L S; Baudot, J; Bekele, S; Belaga, V V; Bellingeri-Laurikainen, A; Bellwied, R; Bezverkhny, B I; Bhardwaj, S; Bhasin, A; Bhati, A K; Bichsel, H; Bielcik, J; Bielcikova, J; Bland, L C; Blyth, C O; Blyth, S L; Bonner, B E; Botje, M; Bouchet, J; Brandin, A V; Bravar, A; Bystersky, M; Cadman, R V; Cai, X Z; Caines, H; Calderón de la Barca-Sanchez, M; Castillo, J; Catu, O; Cebra, D; Chajecki, Z; Chaloupka, P; Chattopadhyay, S; Chen, H F; Chen, J H; Chen, Y; Cheng, J; Cherney, M; Chikanian, A; Choi, H A; Christie, W; Coffin, J P; Cormier, T M; Cosentino, M R; Cramer, J G; Crawford, H J; Das, D; Das, S; Daugherity, M; De Moura, M M; Dedovich, T G; De Phillips, M; Derevshchikov, A A; Didenko, L; Dietel, T; Djawotho, P; Dogra, S M; Dong, W J; Dong, X; Draper, J E; Du, F; Dunin, V B; Dunlop, J C; Dutta-Majumdar, M R; Eckardt, V; Edwards, W R; Efimov, L G; Emelianov, V; Engelage, J; Eppley, G; Erazmus, B; Estienne, M; Fachini, P; Fatemi, R; Fedorisin, J; Filimonov, K; Filip, P; Finch, E; Fine, V; Fisyak, Yu; Fu, J; Gagliardi, C A; Gaillard, L; Gans, J; Ganti, M S; Ghazikhanian, V; Ghosh, P; González, J E; Gorbunov, Y G; Gos, H; Grebenyuk, O; Grosnick, D P; Guertin, S M; Guimaraes, K S F F; Guo, Y; Gupta, N; Gutíerrez, T D; Haag, B; Hallman, T J; Hamed, A; Harris, J W; He, W; Heinz, M; Henry, T W; Hepplemann, S; Hippolyte, B; Hirsch, A; Hjort, E; Hoffmann, G W; Horner, M J; Huang, H Z; Huang, S L; Hughes, E W; Humanic, T J; Igo, G; Jacobs, P; Jacobs, W W; Jakl, P; Jia, F; Jiang, H; Jones, P G; Judd, E G; Kabana, S; Kang, K; Kapitan, J; Kaplan, M; Keane, D; Kechechyan, A; Khodyrev, V Yu; Kim, B C; Kiryluk, J; Kisiel, A; Kislov, E M; Klein, S R; Koetke, D D; Kollegger, T; Kopytine, M; Kotchenda, L; Kouchpil, V; Kowalik, K L; Krämer, M; Kravtsov, P; Kravtsov, V I; Krüger, K; Kuhn, C; Kulikov, A I; Kumar, A; Kuznetsov, A A; Lamont, M A C; Landgraf, J M; Lange, S; La Pointe, S; Laue, F; Lauret, J; Lebedev, A; Lednicky, R; Lee, C H; Lehocka, S; Le Vine, M J; Li, C; Li, Q; Li, Y; Lin, G; Lindenbaum, S J; Lisa, M A; Liu, F; Liu, H; Liu, J; Liu, L; Liu, Z; Ljubicic, T; Llope, W J; Long, H; Longacre, R S; López-Noriega, M; Love, W A; Lu, Y; Ludlam, T; Lynn, D; Ma, G L; Ma, J G; Ma, Y G; Magestro, D; Mahapatra, D P; Majka, R; Mangotra, L K; Manweiler, R; Margetis, S; Markert, C; Martin, L; Matis, H S; Matulenko, Yu A; McClain, C J; McShane, T S; Melnik, Yu M; Meschanin, A; Miller, M L; Minaev, N G; Mioduszewski, S; Mironov, C; Mischke, A; Mishra, D K; Mitchell, J; Mohanty, B; Molnár, L; Moore, C F; Morozov, D A; Munhoz, M G; Nandi, B K; Nattrass, C; Nayak, T K; Nelson, J M; Netrakanti, P K; Nikitin, V A; Nogach, L V; Nurushev, S B; Odyniec, Grazyna Janina; Ogawa, A; Okorokov, V; Oldenburg, M; Olson, D; Pachr, M; Pal, S K; Panebratsev, Yu A; Panitkin, S Y; Pavlinov, A I; Pawlak, T; Peitzmann, T; Perevozchikov, V; Perkins, C; Peryt, W; Petrov, V A; Phatak, S C; Picha, R; Planinic, M; Pluta, J; Poljak, N; Porile, N; Porter, J; Poskanzer, A M; Potekhin, M V; Potrebenikova, E V; Potukuchi, B V K S; Prindle, D; Pruneau, C; Putschke, J; Rakness, G; Raniwala, R; Raniwala, S; Ray, R L; Razin, S V; Reinnarth, J; Relyea, D; Retière, F; Ridiger, A; Ritter, H G; Roberts, J B; Rogachevski, O V; Romero, J L; Rose, A; Roy, C; Ruan, L; Russcher, M J; Sahoo, R; Sakrejda, I; Salur, S; Sandweiss, J; Sarsour, M; Sazhin, P S; Schambach, J; Scharenberg, R P; Schmitz, N; Schweda, K; Seger, J; Selyuzhenkov, I; Seyboth, P; Shabetai, A; Shahaliev, E; Shao, M; Sharma, M; Shen, W Q; Shimansky, S S; ESichtermann; Simon, F; Singaraju, R N; Smirnov, N; Snellings, R; Sood, G; Sørensen, P; Sowinski, J; Speltz, J; Spinka, H M; Srivastava, B; Stadnik, A; Stanislaus, T D S; Stock, R; Stolpovsky, A; Strikhanov, M N; Stringfellow, B C; Suaide, A A P; Sugarbaker, E R; Sumbera, M; Sun, Z; Surrow, B; Swanger, M; Symons, T J M; Szanto de Toledo, A; Tai, A; Takahashi, J; Tang, A H; Tarnowsky, T J; Thein, D; Thomas, J H; Timmins, A R; Timoshenko, S; Tokarev, M; Trainor, T A; Trentalange, S; Tribble, R E; Tsai, O D; Ulery, J; Ullrich, T; Underwood, D G; Van, G; Buren; Van der Kolk, N; Van Leeuwen, M; Van der Molen, A M; Varma, R; Vasilevski, I M; Vasilev, A N; Vernet, R; Vigdor, S E; Viyogi, Y P; Vokal, S; Voloshin, S A; Waggoner, W T; Wang, F; Wang, G; Wang, J S; Wang, X L; Wang, Y; Watson, J W; Webb, J C; Westfall, G D; Wetzler, A; Whitten, C; Wieman, H; Wissink, S W; Witt, R; Wood, J; Wu, J; Xu, N; Xu, Q H; Xu, Z; Yepes, P; Yoo, I K; Yurevich, V I; Zhan, W; Zhang, H; Zhang, W M; Zhang, Y; Zhang, Z P; Zhao, Y; Zhong, C; Zoulkarneev, R; Zoulkarneeva, Y; Zubarev, A N; Zuo, J X

    2006-01-01

    We present the scaling properties of Lambda, Xi, Omega and their anti-particles produced at mid-rapidity in Au+Au collisions at RHIC at sqrt(s_NN) = 200 GeV. The yield of multi-strange baryons per participant nucleon increases from peripheral to central collisions more rapidly than the Lambda yield, which appears to correspond to an increasing strange quark density of matter produced. The value of the strange phase space occupancy factor gamma_s, obtained from a thermal model fit to the data, approaches unity for the most central collisions. We also show that the nuclear modification factors, R_CP, of Lambda and Xi are consistent with each other and with that of protons in the transverse momentum range 2.0 < p_T < 5.0 GeV/c. This scaling behaviour is consistent with a scenario of hadron formation from constituent quark degrees of freedom through quark recombination or coalescence.

  14. Small- and Large-scale Characterization and Mixing Properties in a Thermally Driven Thin Liquid Film

    Winkler, Michael

    2015-01-01

    Thin liquid films are nanoscopic elements of foams, emulsions and suspensions, and form a paradigm for nanochannel transport that eventually test the limits of hydrodynamic descriptions. Here we use classical dynamical systems characteristics to study the complex interplay of thermal convection, interface and gravitational forces which yields turbulent mixing and transport: Lyapunov exponents and entropies. We induce a stable two eddy convection in an extremely thin liquid film by applying a temperature gradient. Experimentally, we determine the small-scale dynamics using the motion and deformation of spots of equal size/equal color, we dubbed that technique "color imaging velocimetry". The large-scale dynamics is captured by encoding the left/right motion of the liquid directed to the left or right of the separatrix between the two rolls. This way, we characterize chaos of course mixing in this peculiar fluid geometry of a thin, free-standing liquid film.

  15. Direct determination of three-phase contact line properties on nearly molecular scale.

    Winkler, P M; McGraw, R L; Bauer, P S; Rentenberger, C; Wagner, P E

    2016-01-01

    Wetting phenomena in multi-phase systems govern the shape of the contact line which separates the different phases. For liquids in contact with solid surfaces wetting is typically described in terms of contact angle. While in macroscopic systems the contact angle can be determined experimentally, on the molecular scale contact angles are hardly accessible. Here we report the first direct experimental determination of contact angles as well as contact line curvature on a scale of the order of 1nm. For water nucleating heterogeneously on Ag nanoparticles we find contact angles around 15 degrees compared to 90 degrees for the corresponding macroscopically measured equilibrium angle. The obtained microscopic contact angles can be attributed to negative line tension in the order of -10(-10) J/m that becomes increasingly dominant with increasing curvature of the contact line. These results enable a consistent theoretical description of heterogeneous nucleation and provide firm insight to the wetting of nanosized objects. PMID:27183880

  16. Development of a Large Scale Infiltration Tank for Determination of the Hydraulic Properties of Expansive Clays

    TANG, Anh Minh; Ta, An-Ninh; Cui, Yu-Jun; THIRIAT, Jérémy

    2009-01-01

    International audience A large-scale infiltration tank was developed to study the water transfer in compacted expansive clay. Volumetric water content sensors were buried in a soil column for water content monitoring during infiltration. In addition to water content, soil suction and temperature at various locations and the heave at the soil surface were also monitored. Emphasis was put in minimizing the effect of sensors installation on water transfer and soil deformation. The results obt...

  17. Psychometric Properties of the Persian Version of Self-Transcendence Scale: Adolescent Version

    Farahani, Azam Shirinabadi; Rassouli, Maryam; Yaghmaie, Farideh; Majd, Hamid Alavi; Sajjadi, Moosa

    2016-01-01

    Background: Given the greater tendency during adolescence toward risk-taking, identifying and measuring the factors affecting the adolescents’ health is highly important to ensure the efficacy of health promoting interventions. One of these factors is self-transcendence. The aim of this study was to assess the psychometric features of the Self-Transcendence Scale (adolescents’ version) in students in Tehran, the capital city of Iran. Methods: This research was conducted in 2015. For this purp...

  18. Psychometric Properties of the Persian Version of Self-Transcendence Scale: Adolescent Version

    AzamShirinabadi Farahani; Maryam Rassouli; Farideh Yaghmaie; Hamid Alavi Majd; Moosa Sajjadi

    2016-01-01

    Background: Given the greater tendency during adolescence toward risk-taking, identifying and measuring the factors affecting the adolescents’ health is highly important to ensure the efficacy of health promoting interventions. One of these factors is self-transcendence. The aim of this study was to assess the psychometric features of the Self-Transcendence Scale (adolescents’ version) in students in Tehran, the capital city of Iran. Methods: This research was conducted in 2015. For this p...

  19. The Luxembourg Workplace Mobbing Scale: Psychometric properties of a short instrument in three different languages

    Steffgen, Georges; Sischka, Philipp; Alexander F Schmidt; Kohl, Diane; Happ, Christian

    2016-01-01

    Workplace mobbing is a serious phenomenon that is costly to organizations and has various negative consequences of those targeted. The main purpose of the present study was to develop and validate a new short scale of workplace mobbing experience in three different language versions (German, French, Luxembourgish). Data were collected via computer-assisted telephone interviews in a sample of 1500 employees working in Luxembourg (aged from 17 to 64; 52.7 % male) that was representative of the ...

  20. Dynamics and Scaling Properties of Fractures in clay-like Materials

    Walmann, Thomas

    1998-12-31

    Computer models that can help oil companies predict realistic and physically correct fracture patterns are important. To verify such a model, experiments described in this thesis were undertaken, using wet clay and powder. The main focus was on extensional fractures, but other types of fractures were also studied. High resolution digital images of the fracture patterns were recorded and analyzed using statistical physics and fractal geometry. The characteristic shapes and size distributions of individual fractures and the overall fracture patterns obtained from laboratory model studies were compared to results from aerial photographs of a fracture pattern in a collapsed glacier that had undergone a similar deformation. A new scaling relation (a power-law) between the length of a fracture and the projected area is derived for fractures formed during clay model experiments. This scaling relation is found also in a field study of a fracture pattern in a glacier. The forms of the different distributions that characterizes fractures in clay experiments are discussed. Several characteristic lengths are associated with the laboratory experiments. They are related to the sample size and shape, the model material and the nature of the imposed deformation. The roughness of the fracture traces obtained from powder experiments was found to have a self-affine form. The roughness, or Hurst exponent, was found to have the value 0.73, plus or minus 0.09. A large number of interacting fractures were formed in the systems studied, and under such conditions the fluctuations about the direction perpendicular to the principle strain direction are influenced by neighbouring fractures. As expected, an upper cutoff for the scaling range was observed. But the length at which the crossover from a self-affine shape to a flat shape took place did not depend systematically on any of the experimental parameters or characteristic length scales. The total fracture trace patterns could not be

  1. Preparation and some properties of type I collagen from fish scales.

    Nomura, Y; Sakai, H; Ishii, Y; Shirai, K

    1996-12-01

    Soluble collagen from fish (sardine) scales was yielded at about 5% with 0.5 M acetic acid after demineralization with EDTA, while a great portion of the collagen remained insoluble. The solubility of this insoluble collagen was about 20% at 45 degrees C (denaturation temperature of soluble collagen) for 24 h. The remaining 80% of the insoluble collagen was denatured in the form of insoluble gelatin, and that may be an interesting food material. PMID:8988647

  2. Psychometric Properties of the Dietary Salt Reduction Self-Care Behavior Scale.

    Srikan, Pratsani; Phillips, Kenneth D

    2014-06-19

    Valid, reliable, and culturally-specific scales to measure salt reduction self-care behavior in older adults are needed. The purpose of this study was to develop the Dietary Salt Reduction Self-Care Behavior Scale (DSR-SCB) for use in hypertensive older adults with Orem's self-care deficit theory as a base. Exploratory factor analysis, Rasch modeling, and reliability were performed on data from 242 older Thai adults. Nine items loaded on one factor (factor loadings = 0.63 to 0.79) and accounted for 52.28% of the variance (Eigenvalue = 4.71). The Kaiser-Meyer-Olkin method of sampling adequacy was 0.89, and the Bartlett's test showed significance (χ(2) (df =36) = 916.48, p < 0.0001). Infit and outfit mean squares ranged from 0.81 to 1.25, while infit and outfit standardized mean squares were located at ±2. Cronbach's alpha was 0.88. The 9-item DSR-SCB is a short and reliable scale. PMID:24951525

  3. Physical properties of type I collagen extracted from fish scales of Pagrus major and Oreochromis niloticas.

    Ikoma, Toshiyuki; Kobayashi, Hisatoshi; Tanaka, Junzo; Walsh, Dominic; Mann, Stephen

    2003-09-01

    Type I collagens were extracted from fish scales of Pagrus major and Oreochromis niloticas as a possible underutilized resource for medical materials. The fish scales were demineralized with EDTA and digested by pepsin. The resultant type I collagens contained more than 33.6% of glycine as the most abundant amino acid. The denaturation temperatures of the collagens from P. major and O. niloticas were 303 and 308K, respectively, both of which were relatively lower than that of porcine dermis collagen (314K). CD spectra indicated that the denaturation temperatures were dependent on the amount of hydroxyproline, rather than proline residues. Raman spectra also indicated that the relative intensities of Raman lines at 879 and 855cm(-1) assigned to Hyp and Pro rings were changed due to the contents of the imino acids. Significantly, the content of sulphur-containing methionine was higher in the fish scales than in porcine dermis. The enthalpy and entropy estimated from thermal analyses could be correlated to amino acid sequences (Gly-Pro-Hyp) of type I collagens and the number of methionine amino acid residues. PMID:12957317

  4. The Wear Properties of Tungsten Carbide-Cobalt Hardmetals from the Nanoscale up to the Macroscopic Scale

    Ndlovu, Siphilisiwe

    2009-01-01

    A study has been conducted on the tribological properties of WC-Co hardmetals by carrying out a series of wear tests from the nanoscale up to the macroscopic scale. The composition of the hardmetals was varied and the binder content ranged from 6 to 15 wt%. The binder in all the samples was cobalt and one of the samples had small additions of Cr3C2 and VC. The WC grain size in the samples ranged from 250 nm (nano-size) up to 2.65 µm (coarse-grained). A binderless WC sample and a pure cobalt s...

  5. Microstructure Scaling Properties and Fatigue Resistance of Pre-Strained Aluminium Alloys (Part 1: Al-Cu alloy)

    Froustey, C.; NAIMARK, O.; BANNIKOV, M.; Oborin, V.

    2010-01-01

    Abstract The objective of this work is to provide the link between the fatigue behaviour of pre-strained aluminium alloys and the scaling properties of damage induced on the fracture surface. Fatigue tests performed on pre-strained aluminium alloys revealed a large difference in their residual fatigue resistance linked to the material: the Al-Cu alloy demonstrated a sharp decrease of HCF life-time due to the pre-straining whereas the insensitivity of the Al-Mg alloy was clear. For ...

  6. The transport properties of the molecular-scale B{sub 2}C and BC{sub 3} electronic devices

    Li Guiqin, E-mail: ligqin@mail.tsinghua.edu.cn [Department of Physics, Tsinghua University, Beijing 100084 (China); Li Runqin [Inner Mongolia Radio and TV University, 010010 (China)

    2012-09-01

    The transport properties of the molecular-scale B{sub 2}C and BC{sub 3} electronic devices are investigated with an ab initio method combined with a nonequilibrium Green function technique. The effects of different BC graphenes and ribbon lengths on the transport properties of the devices are significant. The results show that the devices with different BC graphenes and sizes have unusual transmission coefficients, which leads to special current transport mechanisms for the devices. Notably, the current strength of the device with the shortest ribbon length is the largest in three B{sub 2}C devices, but the current strength of the device with the shortest ribbon length is the smallest for BC{sub 3} device.

  7. The Effortful Control Scale for adults: psychometric properties of the Catalan version and its relationship to cognitive emotion regulation

    Miquel Tortella-Feliu

    2013-10-01

    Full Text Available The goals of this study were (a to examine the psychometric properties of a Catalan version of the Effortful control scale of the Adult Temperament Questionnaire short-form and (b to analyze the relationships among effortful control (EC, negative affectivity (NA, and the use of negative cognitive emotion regulation (ER strategies. In a sample of 353 college students, the instrument presents acceptable internal consistency, temporal stability and convergent validity; however, in general, psychometric properties are poorer than those reported for other versions. Confirmatory factor analysis fit indices revealed an overall poor fit for the three-factor theoretical model. Additionally, it has been found that the proneness to engage in negative cognitive ER strategies was mainly related with exhibiting high NA. Further, although such tendencies were also influenced by EC capabilities, data did not show EC moderating the relationships among NA, anxiety, and the use of negative cognitive ER strategies.

  8. Microstructural and Morphological Factors Affecting Uncertainty in Small Scale Mechanical Properties

    Maughan, Michael R.

    If materials are to be developed from the ground up, the process will be dependent upon accurate and well-defined models of material behavior. These models can be closed-form solutions developed from first principles, simulations, or empirically derived equations, among others. Material behavior at the mesoscale is in general well understood, having had several centuries of study. However, behavior at the micro or nanoscale still requires characterization. Understanding the collective influence of the microstructure on the bulk material, for example with models like the Hall-Petch relation, has advanced our ability to manipulate the material to our advantage. We now have the ability to study not only the structure of the material, but also the material behavior and properties at the nanoscale. Understanding this behavior is critical to developing a framework for interpreting and utilizing these properties in materials design. This research aims to improve the fundamental understanding of the mechanical performance of materials and the subsequent variation in measured properties. The literature reports widely varying material properties such as hardness, elastic modulus, and yield point when measured at the nanoscale. Proposed variation mechanisms in these properties include surface preparation, error in measurement, heterogeneous dislocation density and distribution, crystal orientation, surface oxide film fracture, and others. Among other things, this work shows that these sources of variation can be determined and quantified, and that this information can be utilized as a characterization and/or predictive tool. The main goals of this work are to 1) continue basic research on sources of variation in the nanoscale properties of materials, specifically hardness and modulus in crystalline and glassy solids, 2) study the abrupt transition from elastic to plastic material behavior known as pop-in and resolve the problem of pseudo-elastic behavior prior to plasticity

  9. Multi-scale cellulose based new bio-aerogel composites with thermal super-insulating and tunable mechanical properties.

    Seantier, Bastien; Bendahou, Dounia; Bendahou, Abdelkader; Grohens, Yves; Kaddami, Hamid

    2016-03-15

    Bio-composite aerogels based on bleached cellulose fibers (BCF) and cellulose nanoparticles having various morphological and physico-chemical characteristics are prepared by a freeze-drying technique and characterized. The various composite aerogels obtained were compared to a BCF aerogel used as the reference. Severe changes in the material morphology were observed by SEM and AFM due to a variation of the cellulose nanoparticle properties such as the aspect ratio, the crystalline index and the surface charge density. BCF fibers form a 3D network and they are surrounded by the cellulose nanoparticle thin films inducing a significant reduction of the size of the pores in comparison with a neat BCF based aerogel. BET analyses confirm the appearance of a new organization structure with pores of nanometric sizes. As a consequence, a decrease of the thermal conductivities is observed from 28mWm(-1)K(-1) (BCF aerogel) to 23mWm(-1)K(-1) (bio-composite aerogel), which is below the air conductivity (25mWm(-1)K(-1)). This improvement of the insulation properties for composite materials is more pronounced for aerogels based on cellulose nanoparticles having a low crystalline index and high surface charge (NFC-2h). The significant improvement of their insulation properties allows the bio-composite aerogels to enter the super-insulating materials family. The characteristics of cellulose nanoparticles also influence the mechanical properties of the bio-composite aerogels. A significant improvement of the mechanical properties under compression is obtained by self-organization, yielding a multi-scale architecture of the cellulose nanoparticles in the bio-composite aerogels. In this case, the mechanical property is more dependent on the morphology of the composite aerogel rather than the intrinsic characteristics of the cellulose nanoparticles. PMID:26794770

  10. Topological Properties of Large-Scale Cortical Networks Based on Multiple Morphological Features in Amnestic Mild Cognitive Impairment.

    Li, Qiongling; Li, Xinwei; Wang, Xuetong; Li, Yuxia; Li, Kuncheng; Yu, Yang; Yin, Changhao; Li, Shuyu; Han, Ying

    2016-01-01

    Previous studies have demonstrated that amnestic mild cognitive impairment (aMCI) has disrupted properties of large-scale cortical networks based on cortical thickness and gray matter volume. However, it is largely unknown whether the topological properties of cortical networks based on geometric measures (i.e., sulcal depth, curvature, and metric distortion) change in aMCI patients compared with normal controls because these geometric features of cerebral cortex may be related to its intrinsic connectivity. Here, we compare properties in cortical networks constructed by six different morphological features in 36 aMCI participants and 36 normal controls. Six cortical features (3 volumetric and 3 geometric features) were extracted for each participant, and brain abnormities in aMCI were identified by cortical network based on graph theory method. All the cortical networks showed small-world properties. Regions showing significant differences mainly located in the medial temporal lobe and supramarginal and right inferior parietal lobe. In addition, we also found that the cortical networks constructed by cortical thickness and sulcal depth showed significant differences between the two groups. Our results indicated that geometric measure (i.e., sulcal depth) can be used to construct network to discriminate individuals with aMCI from controls besides volumetric measures. PMID:27057360

  11. The Challenges Of Investigating And Remediating Port Hope's Small-Scale Urban Properties - 13115

    Veen, Walter van; Case, Glenn; Benson, John; Herod, Judy [Atomic Energy of Canada Limited, Port Hope, Ontario (Canada); Yule, Adam [Public Works and Government Services Canada, Port Hope, Ontario (Canada)

    2013-07-01

    An important component of the Port Hope Project, the larger of the two projects comprising the Port Hope Area Initiative (PHAI), is the investigation of all 4,800 properties in the Municipality of Port Hope for low level radioactive waste (LLRW) and the remediation of approximately 10% of these. Although the majority of the individual properties are not expected to involve technically sophisticated remediation programs, the large number of property owners and individually unique properties are expected to present significant logistic challenges that will require a high degree of planning, organization and communication. The protocol and lessons learned described will be of interest to those considering similar programs. Information presented herein is part of a series of papers presented by the PHAI Management Office (PHAI MO) at WM Symposium '13 describing the history of the Port Hope Project and current project status. Other papers prepared for WM Symposium '13 address the large-scale site cleanup and the construction of the long-term waste management facility (LTWMF) where all of the LLRW will be consolidated and managed within an engineered, above-ground mound. (authors)

  12. Structural Analysis of Laplacian Spectral Properties of Large-Scale Networks

    Preciado, Victor M.; Jadbabaie, Ali; Verghese, George C.

    2011-01-01

    Using methods from algebraic graph theory and convex optimization, we study the relationship between local structural features of a network and spectral properties of its Laplacian matrix. In particular, we derive expressions for the so-called spectral moments of the Laplacian matrix of a network in terms of a collection of local structural measurements. Furthermore, we propose a series of semidefinite programs to compute bounds on the spectral radius and the spectral gap of the Laplacian mat...

  13. The size distribution, scaling properties and spatial organization of urban clusters: a global and regional perspective

    Fluschnik, Till; Kriewald, Steffen; Ros, Anselmo García Cantú; Zhou, Bin; Reusser, Dominik E.; Kropp, Jürgen P.; Rybski, Diego

    2014-01-01

    Human development has far-reaching impacts on the surface of the globe. The transformation of natural land cover occurs in different forms and urban growth is one of the most eminent transformative processes. We analyze global land cover data and extract cities as defined by maximally connected urban clusters. The analysis of the city size distribution for all cities on the globe confirms Zipf's law. Moreover, by investigating the percolation properties of the clustering of urban areas we ass...

  14. On the Properties of Slow MHD Sausage Waves within Small-scale Photospheric Magnetic Structures

    Freij, N.; Dorotovič, I.; Morton, R. J.; Ruderman, M. S.; Karlovský, V.; Erdélyi, R.

    2016-01-01

    The presence of magnetoacoustic waves in magnetic structures in the solar atmosphere is well-documented. Applying the technique of solar magneto-seismology (SMS) allows us to infer the background properties of these structures. Here, we aim to identify properties of the observed magnetoacoustic waves and study the background properties of magnetic structures within the lower solar atmosphere. Using the Dutch Open Telescope and Rapid Oscillations in the Solar Atmosphere instruments, we captured two series of high-resolution intensity images with short cadences of two isolated magnetic pores. Combining wavelet analysis and empirical mode decomposition (EMD), we determined characteristic periods within the cross-sectional (i.e., area) and intensity time series. Then, by applying the theory of linear magnetohydrodynamics (MHD), we identified the mode of these oscillations within the MHD framework. Several oscillations have been detected within these two magnetic pores. Their periods range from 3 to 20 minutes. Combining wavelet analysis and EMD enables us to confidently find the phase difference between the area and intensity oscillations. From these observed features, we concluded that the detected oscillations can be classified as slow sausage MHD waves. Furthermore, we determined several key properties of these oscillations such as the radial velocity perturbation, the magnetic field perturbation, and the vertical wavenumber using SMS. The estimated range of the related wavenumbers reveals that these oscillations are trapped within these magnetic structures. Our results suggest that the detected oscillations are standing harmonics, and this allows us to estimate the expansion factor of the waveguides by employing SMS. The calculated expansion factor ranges from 4 to 12.

  15. The Interpersonal Shame Inventory for Asian Americans: Scale Development and Psychometric Properties

    Wong, Y. Joel; Kim, Bryan S. K.; Nguyen, Chi P.; Cheng, Janice Ka Yan; Saw, Anne

    2013-01-01

    This article reports the development and psychometric properties of the Interpersonal Shame Inventory (ISI), a culturally salient and clinically relevant measure of interpersonal shame for Asian Americans. Across 4 studies involving Asian American college students, the authors provided evidence for this new measure’s validity and reliability. Exploratory factor analyses and confirmatory factor analyses provided support for a model with 2 correlated factors: external shame (arising from concer...

  16. A kinetic model and scaling properties of non-equilibrium clustering of self-propelled particles

    We demonstrate that the clustering statistics and the corresponding phase transition to non-equilibrium clustering found in many experiments and simulation studies with self-propelled particles (SPPs) with alignment can be obtained by a simple kinetic model. The key elements of this approach are the scaling of the cluster cross-section with cluster size—described by an exponent α—and the scaling of the cluster perimeter with cluster size—described by an exponent β. The analysis of the kinetic approach reveals that the SPPs exhibit two phases: (i) an individual phase, where the cluster size distribution (CSD) is dominated by an exponential tail that defines a characteristic cluster size, and (ii) a collective phase characterized by the presence of a non-monotonic CSD with a local maximum at large cluster sizes. Through a finite-size study of the kinetic model, we show that the critical point Pc that separates the two phases scales with the system size N as Pc∝N−ξ, while the CSD p(m), at the critical point Pc, is always a power law such that p(m)∝m−γ, where m is the cluster size. Our analysis shows that the critical exponents ξ and γ are a function of α and β, and even provides the relationship between them. Furthermore, the kinetic approach suggests that in the thermodynamic limit, a genuine clustering phase transition, in two and three dimensions, requires that α = β. Interestingly, the critical exponent γ is found to be in the range 0.8 < γ < 1.5 in line with the observations from experiments and simulations. (paper)

  17. Length Scale Dependence of the Dynamic Properties of Hyaluronic Acid Solutions in the Presence of Salt

    Horkay, Ferenc; Falus, Peter; Hecht, Anne-Marie; Geissler, Erik (CNRS-UMR); (NIH); (ILL)

    2010-12-07

    In solutions of the charged semirigid biopolymer hyaluronic acid in salt-free conditions, the diffusion coefficient D{sub NSE} measured at high transfer momentum q by neutron spin echo is more than an order of magnitude smaller than that determined by dynamic light scattering, D{sub DLS}. This behavior contrasts with neutral polymer solutions. With increasing salt content, D{sub DLS} approaches D{sub NSE}, which is independent of ionic strength. Contrary to theoretical expectation, the ion-polymer coupling, which dominates the low q dynamics of polyelectrolyte solutions, already breaks down at distance scales greater than the Debye-Hueckel length.

  18. Scaling Properties of the Giant Dipole Resonance Width in Hot Rotating Nuclei

    We study the systematics of the giant dipole resonance width Γ in hot rotating nuclei as a function of temperature T , spin J , and mass A . We compare available experimental results with theoretical calculations that include thermal shape fluctuations in nuclei ranging from A=45 to A=208 . Using the appropriate scaled variables, we find a simple phenomenological function Γ(A,T,J) which approximates the global behavior of the giant dipole resonance width in the liquid drop model. We reanalyze recent experimental and theoretical results for the resonance width in Sn isotopes and 208Pb . copyright 1998 The American Physical Society

  19. Length Scale Dependence of the Dynamic Properties of Hyaluronic Acid Solutions in the Presence of Salt

    In solutions of the charged semirigid biopolymer hyaluronic acid in salt-free conditions, the diffusion coefficient DNSE measured at high transfer momentum q by neutron spin echo is more than an order of magnitude smaller than that determined by dynamic light scattering, DDLS. This behavior contrasts with neutral polymer solutions. With increasing salt content, DDLS approaches DNSE, which is independent of ionic strength. Contrary to theoretical expectation, the ion-polymer coupling, which dominates the low q dynamics of polyelectrolyte solutions, already breaks down at distance scales greater than the Debye-Hueckel length.

  20. Properties of internal planetary-scale inertio gravity waves in the mesosphere

    H. G. Mayr; J. G. Mengel; E. R. Talaat; H. S. Porter; Chan, K. L.

    2004-01-01

    International audience At high latitudes in the upper mesosphere, horizontal wind oscillations have been observed with periods around 10h. Waves with such a period are generated in our Numerical Spectral Model (NSM), and they are identified as planetary-scale inertio gravity waves (IGW). These IGWs have periods between 9 and 11h and appear above 60km in the zonal mean (m=0), as well as in m=1 to 4, propagating eastward and westward. Under the influence of the Coriolis force, the amplitudes...

  1. Parsec scale polarization properties of the TeV blazar Markarian 421

    Lico, R.; Giroletti, M.; Orienti, M.; Gomez, J.L.; Casadio, C.; D'Ammando, F.; Blasi, M. G.; Cotton, W.; Edwards, P G; Fuhrmann, L.; S. Jorstad(); Kino, M; Y. Y. Kovalev(Astro Space Center of the Lebedev Physical Institute, Moscow, Russia); Krichbaum, T. P.; Marscher, A. P.

    2015-01-01

    In this work we present a polarization analysis at radio frequencies of Markarian 421, one of the closest (z=0.03) TeV blazars. The observations were obtained, both in total and in polarized intensity, with the Very Long Baseline Array (VLBA) at 15, 24, and 43 GHz throughout 2011, with one observation per month (for a total of twelve epochs). We investigate the magnetic field topology and the polarization structure on parsec scale and their evolution with time. We detect polarized emission bo...

  2. SCALING PROPERTIES OF FLUCTUATION RESULTS FROM THE PHENIX EXPERIMENT AT RHIC.

    MITCHELL,J.T.

    2006-06-05

    The PHENIX Experiment at the Relativistic Heavy Ion Collider has made measurements of event-by-event fluctuations in the charged particle multiplicity as a function of collision energy, centrality, collision species, and transverse momentum in several heavy ion collision systems. It is observed that the fluctuations in terms of {sigma}{sup 2}/{mu}{sup 2} exhibit a universal power-law scaling as a function of N{sub participants} that is independent of the transverse momentum range of the measurement.

  3. Propriedades psicométricas da Dutch Fatigue Scale e Dutch Exertion Fatigue Scale: versão brasileira Propiedades psicométricas de la Dutch Fatigue Scale y Dutch Exertion Fatigue Scale: versión Brasileña Psychometric properties of the Dutch Fatigue Scale and the Dutch Exertion Fatigue Scale: Brazilian version

    Andrea Fini

    2010-04-01

    propiedades similares a las das escalas originais.Fatigue is a human response in varied acute and chronic conditions and also in general population. This article reports a study conducted to estimate reliability and validity of the Dutch Fatigue Scale (DUFS and the Dutch Exertion Fatigue Scale (DEFS adapted for Brazilian use. Three-hundred heart failure patients and 64 healthier volunteers answered the DUFS and DEFS translated into Portuguese. Factorial analysis of DUFS and DEFS items yield a solution with one factor for each scale (explained variance = 53.9%, and good reliability estimates were obtained by the Chronbach's alpha (DUFS=.85 e DEFS=.92. In the patient sample, scales scores were positively associated with heart failure functional class (DUFS and DEFS p=.00, depression scores (DUFS r s=.63; p=.00 and DEFS r s=.55; p=.00, and sleep disturbance (DUFS and DEFS p=.00. Brazilian versions of DUFS and DEFS presented psychometric properties similar to those of the original ones.

  4. Object-based image analysis for scaling properties of rangeland ecosystems: Linking field and image data for management decision making

    Karl, Jason William

    Management of semi-arid shrub-steppe ecosystems (i.e., rangelands) requires accurate information over large landscapes, and remote sensing is an attractive option for collecting such data. To successfully use remotely-sensed data in landscape-level rangeland management, questions as to the relevance of image data to landscape patterns and optimal scales of analysis must be addressed. Object-based image analysis (OBIA), which segments image pixels into homogeneous regions, or objects, has been suggested as a way to increase accuracy of remotely-sensed products, but little research has gone into how to determine sizes of image objects with regard to scaling of ecosystem properties. The purpose of my dissertation was to determine if OBIA could be used to generate observational scales to match ecological scales in rangelands and to explore the potential for OBIA to generate accurate and repeatable remote-sensing products for managers. The work presented here was conducted in southern Idaho's Snake River Plain region. By comparing OBIA segmentation of satellite imagery into successively coarser objects to pixel-based aggregation methods, I found that canonical correlations between field-collected and image data were similar at the finest scales, but higher for image segmentation as scale increased. I also detected scaling thresholds with image segmentation that were confirmed via semi-variograms of field data. This approach proved useful for evaluating the overall utility of an image to address an objective, and identifying scaling limits for analysis. I next used observations of percent bare-ground cover from 346 field sites to consider how hierarchies of image objects created through OBIA could be used to discover appropriate scales for analysis given a specific objective. Using a regression-based approach, I found that segmentation levels whose predictions of bare-ground cover had spatial dependence that most closely matched the spatial dependence of the field

  5. Asymptotic properties of quantum dynamics in bounded domains at various time scales

    We study a peculiar semiclassical limit of the dynamics of quantum states on a circle and in a box (infinitely deep potential well with rigid walls) as the Planck constant tends to zero and time tends to infinity. Our results describe the dynamics of coherent states on the circle and in the box at all time scales in semiclassical approximation. They give detailed information about all stages of quantum evolution in the semiclassical limit. In particular, we rigorously justify the fact that the spatial distribution of a wave packet is most often close to a uniform distribution. This fact was previously known only from numerical experiments. We apply the results obtained to a problem of classical mechanics: deciding whether the recently suggested functional formulation of classical mechanics is preferable to the traditional one. To do this, we study the semiclassical limit of Husimi functions of quantum states. Both formulations of classical mechanics are shown to adequately describe the system when time is not arbitrarily large. But the functional formulation remains valid at larger time scales than the traditional one and, therefore, is preferable from this point of view. We show that, although quantum dynamics in finite volume is commonly believed to be almost periodic, the probability distribution of the position of a quantum particle in a box has a limit distribution at infinite time if we take into account the inaccuracy in measuring the size of the box.

  6. Comparison for Chinese subordinates as a motivation approach: Scale Development and Psychometric Properties

    Jingjing Ge

    2015-11-01

    Full Text Available Purpose: Chinese people are motivated by social comparison and temporal comparison. Based on this finding, we conceptualized lateral comparison and vertical comparison as two distinct constructs that represent individual self-enhancement toward the nature of social comparison with others and temporal comparison with self over time. We hypothesized that as stable individual psychological difference, lateral comparison and vertical comparison would have differential effects on people’s working behavior in the Chinese organizational context. Design/methodology/approach: Based on a conceptualization approach to Chinese management research, we conducted three studies to develop and validate a two-factor comparison scale which includes three-item lateral comparison and a three-item vertical comparison. Findings: Results from qualitative data in Study 1 provide evidence of convergent and discriminate validity of the scale, while Study 2 demonstrates the scale’s predictive validity. Furthermore, in Study two, a field survey in multiple Chinese organizations showed that lateral comparison and vertical comparison had differential effects on employee task performance and organizational citizenship behavior. Research implications: The theoretical and practical implications of this study are discussed in the working context in Chinese organizations and beyond. Originality/value: This finding integrates insights from previous research in social comparison and temporal comparison into a motivation approach that supervisors use toward subordinates in the Chinese organizational context.

  7. Psychometric Properties of the "Sport Motivation Scale (SMS)" Adapted to Physical Education.

    Granero-Gallegos, Antonio; Baena-Extremera, Antonio; Gómez-López, Manuel; Sánchez-Fuentes, José Antonio; Abraldes, J Arturo

    2014-12-01

    The aim of this study was to investigate the factor structure of a Spanish version of the Sport Motivation Scale adapted to physical education. A second aim was to test which one of three hypothesized models (three, five and seven-factor) provided best model fit. 758 Spanish high school students completed the Sport Motivation Scale adapted for Physical Education and also completed the Learning and Performance Orientation in Physical Education Classes Questionnaire. We examined the factor structure of each model using confirmatory factor analysis and also assessed internal consistency and convergent validity. The results showed that all three models in Spanish produce good indicators of fitness, but we suggest using the seven-factor model (χ(2)/gl = 2.73; ECVI = 1.38) as it produces better values when adapted to physical education, that five-factor model (χ(2)/gl = 2.82; ECVI = 1.44) and three-factor model (χ(2)/gl = 3.02; ECVI = 1.53). Key PointsPhysical education research conducted in Spain has used the version of SMS designed to assess motivation in sport, but validity reliability and validity results in physical education have not been reported.Results of the present study lend support to the factorial validity and internal reliability of three alternative factor structures (3, 5, and 7 factors) of SMS adapted to Physical Education in Spanish.Although all three models in Spanish produce good indicators of fitness, but we suggest using the seven-factor model. PMID:25435772

  8. Psychometric Properties of the “Sport Motivation Scale (SMS” Adapted to Physical Education

    Antonio Granero-Gallegos, Antonio Baena-Extremera

    2014-12-01

    Full Text Available The aim of this study was to investigate the factor structure of a Spanish version of the Sport Motivation Scale adapted to physical education. A second aim was to test which one of three hypothesized models (three, five and seven-factor provided best model fit. 758 Spanish high school students completed the Sport Motivation Scale adapted for Physical Education and also completed the Learning and Performance Orientation in Physical Education Classes Questionnaire. We examined the factor structure of each model using confirmatory factor analysis and also assessed internal consistency and convergent validity. The results showed that all three models in Spanish produce good indicators of fitness, but we suggest using the seven-factor model (χ2/gl = 2.73; ECVI = 1.38 as it produces better values when adapted to physical education, that five-factor model (χ2/gl = 2.82; ECVI = 1.44 and three-factor model (χ2/gl = 3.02; ECVI = 1.53.

  9. Psychometric Properties and Diagnostic Accuracy of the Edinburgh Postnatal Depression Scale in a Sample of Iranian Women

    Gholam Reza Kheirabadi

    2012-03-01

    Full Text Available Background: Edinburgh Postnatal Depression Scale (EPDS has been used as a reliable screening tool for postpartum depression in many countries. This study aimed to assess the psychometric properties and diagnostic accuracy of the EPDS in a sample of Iranian women.Methods: Using stratified sampling 262 postpartum women (2 weeks-3 months after delivery were selected from urban and rural health center in the city of Isfahan. They were interviewed using EPDS and Hamilton depression rating scale (HDRS. Data were assessed using factor analysis, diagnosis analysis of receiver operating characteristic (ROC curve, Cronbach's alpha and Pearson correlation coefficient.Results: The age of then participants ranged 18-45 years (26.6±5.1. Based on a cut-off point of >13 for HDRS, 18.3% of the participants. The overall reliability (Cronbach's alpha of EPDS was 0.79. There was a significant correlation (r2=0.60, P value<0.01 between EPDS and HDRS. Two factor analysis showed that anhedonia and depression were two explanatory factors. At a cut-off point12 the sensitivity of the questionnaire was 78% (95% CI: 73%-83% and its specificity was 75% (95% CI: 72%-78%. Conclusion: The Persian version of the EPDS showed appropriate psychometric properties diagnostic accuracy index. It can be used by health system professionals for detection, assessment and treatment for mothers with post partum depression.

  10. A three-scale model of basic mechanical properties of Nafion

    Kafka, Vratislav; Vokoun, David

    2015-01-01

    Roč. 50, č. 6 (2015), s. 763-776. ISSN 0191-5665 R&D Projects: GA ČR(CZ) GAP108/10/1296; GA ČR(CZ) GA103/09/2101 Institutional support: RVO:68378297 ; RVO:68378271 Keywords : Nafion * mechanical properties * mesomechanics * material structure * hydration Subject RIV: JL - Materials Fatigue, Friction Mechanics; JJ - Other Materials (FZU-D) Impact factor: 0.473, year: 2014 http://link.springer.com/article/10.1007%2Fs11029-015-9466-y

  11. Psychometric Properties and Validation of the Arabic Social Media Addiction Scale

    Jamal Al-Menayes

    2015-01-01

    This study investigated the psychometric properties of the Arabic version of the SMAS. SMAS is a variant of IAT customized to measure addiction to social media instead of the Internet as a whole. Using a self-report instrument on a cross-sectional sample of undergraduate students, the results revealed the following. First, the exploratory factor analysis showed that a three-factor model fits the data well. Second, concurrent validity analysis showed the SMAS to be a valid measure of social me...

  12. Impact of Sub-grid Soil Textural Properties on Simulations of Hydrological Fluxes at the Continental Scale Mississippi River Basin

    Kumar, R.; Samaniego, L. E.; Livneh, B.

    2013-12-01

    Knowledge of soil hydraulic properties such as porosity and saturated hydraulic conductivity is required to accurately model the dynamics of near-surface hydrological processes (e.g. evapotranspiration and root-zone soil moisture dynamics) and provide reliable estimates of regional water and energy budgets. Soil hydraulic properties are commonly derived from pedo-transfer functions using soil textural information recorded during surveys, such as the fractions of sand and clay, bulk density, and organic matter content. Typically large scale land-surface models are parameterized using a relatively coarse soil map with little or no information on parametric sub-grid variability. In this study we analyze the impact of sub-grid soil variability on simulated hydrological fluxes over the Mississippi River Basin (≈3,240,000 km2) at multiple spatio-temporal resolutions. A set of numerical experiments were conducted with the distributed mesoscale hydrologic model (mHM) using two soil datasets: (a) the Digital General Soil Map of the United States or STATSGO2 (1:250 000) and (b) the recently collated Harmonized World Soil Database based on the FAO-UNESCO Soil Map of the World (1:5 000 000). mHM was parameterized with the multi-scale regionalization technique that derives distributed soil hydraulic properties via pedo-transfer functions and regional coefficients. Within the experimental framework, the 3-hourly model simulations were conducted at four spatial resolutions ranging from 0.125° to 1°, using meteorological datasets from the NLDAS-2 project for the time period 1980-2012. Preliminary results indicate that the model was able to capture observed streamflow behavior reasonably well with both soil datasets, in the major sub-basins (i.e. the Missouri, the Upper Mississippi, the Ohio, the Red, and the Arkansas). However, the spatio-temporal patterns of simulated water fluxes and states (e.g. soil moisture, evapotranspiration) from both simulations, showed marked

  13. Replication of engine block cylinder bridge microstructure and mechanical properties with lab scale 319 Al alloy billet castings

    Lombardi, A., E-mail: a2lombar@ryerson.ca [Centre for Near-net-shape Processing of Materials, Ryerson University, 101 Gerrard Street East, Toronto, Ontario M5B2K3 (Canada); D' Elia, F.; Ravindran, C. [Centre for Near-net-shape Processing of Materials, Ryerson University, 101 Gerrard Street East, Toronto, Ontario M5B2K3 (Canada); MacKay, R. [Nemak of Canada Corporation, 4600 G.N. Booth Drive, Windsor, Ontario N9C4G8 (Canada)

    2014-01-15

    In recent years, aluminum alloy gasoline engine blocks have in large part successfully replaced nodular cast iron engine blocks, resulting in improved vehicle fuel efficiency. However, because of the inadequate wear resistance properties of hypoeutectic Al–Si alloys, gray iron cylinder liners are required. These liners cause the development of large tensile residual stress along the cylinder bores and necessitate the maximization of mechanical properties in this region to prevent premature engine failure. The aim of this study was to replicate the engine cylinder bridge microstructure and mechanical properties following TSR treatment (which removes the sand binder to enable easy casting retrieval) using lab scale billet castings of the same alloy composition with varying cooling rates. Comparisons in microstructure between the engine block and the billet castings were carried out using optical and scanning electron microscopy, while mechanical properties were assessed using tensile testing. The results suggest that the microstructure at the top and middle of the engine block cylinder bridge was successfully replicated by the billet castings. However, the microstructure at the bottom of the cylinder was not completely replicated due to variations in secondary phase morphology and distribution. The successful replication of engine block microstructure will enable the future optimization of heat treatment parameters. - Highlights: • A method to replicate engine block microstructure was developed. • Billet castings will allow cost effective optimization of heat treatment process. • The replication of microstructure in the cylinder region was mostly successful. • Porosity was more clustered in the billet castings compared to the engine block. • Mechanical properties were lower in billet castings due to porosity and inclusions.

  14. Replication of engine block cylinder bridge microstructure and mechanical properties with lab scale 319 Al alloy billet castings

    In recent years, aluminum alloy gasoline engine blocks have in large part successfully replaced nodular cast iron engine blocks, resulting in improved vehicle fuel efficiency. However, because of the inadequate wear resistance properties of hypoeutectic Al–Si alloys, gray iron cylinder liners are required. These liners cause the development of large tensile residual stress along the cylinder bores and necessitate the maximization of mechanical properties in this region to prevent premature engine failure. The aim of this study was to replicate the engine cylinder bridge microstructure and mechanical properties following TSR treatment (which removes the sand binder to enable easy casting retrieval) using lab scale billet castings of the same alloy composition with varying cooling rates. Comparisons in microstructure between the engine block and the billet castings were carried out using optical and scanning electron microscopy, while mechanical properties were assessed using tensile testing. The results suggest that the microstructure at the top and middle of the engine block cylinder bridge was successfully replicated by the billet castings. However, the microstructure at the bottom of the cylinder was not completely replicated due to variations in secondary phase morphology and distribution. The successful replication of engine block microstructure will enable the future optimization of heat treatment parameters. - Highlights: • A method to replicate engine block microstructure was developed. • Billet castings will allow cost effective optimization of heat treatment process. • The replication of microstructure in the cylinder region was mostly successful. • Porosity was more clustered in the billet castings compared to the engine block. • Mechanical properties were lower in billet castings due to porosity and inclusions

  15. Variability and scaling of hydraulic properties for 200 Area soils, Hanford Site

    Khaleel, R.; Freeman, E.J.

    1995-10-01

    Over the years, data have been obtained on soil hydraulic properties at the Hanford Site. Much of these data have been obtained as part of recent site characterization activities for the Environmental Restoration Program. The existing data on vadose zone soil properties are, however, fragmented and documented in reports that have not been formally reviewed and released. This study helps to identify, compile, and interpret all available data for the principal soil types in the 200 Areas plateau. Information on particle-size distribution, moisture retention, and saturated hydraulic conductivity (K{sub s}) is available for 183 samples from 12 sites in the 200 Areas. Data on moisture retention and K{sub s} are corrected for gravel content. After the data are corrected and cataloged, hydraulic parameters are determined by fitting the van Genuchten soil-moisture retention model to the data. A nonlinear parameter estimation code, RETC, is used. The unsaturated hydraulic conductivity relationship can subsequently be predicted using the van Genuchten parameters, Mualem`s model, and laboratory-measured saturated hydraulic conductivity estimates. Alternatively, provided unsaturated conductivity measurements are available, the moisture retention curve-fitting parameters, Mualem`s model, and a single unsaturated conductivity measurement can be used to predict unsaturated conductivities for the desired range of field moisture regime.

  16. Atomic-scale simulations of material behaviors and tribology properties for BCC metal film

    H, D. Aristizabal; P, A. Parra; P, López; E, Restrepo-Parra

    2016-01-01

    This work has two main purposes: (i) introducing the basic concepts of molecular dynamics analysis to material scientists and engineers, and (ii) providing a better understanding of instrumented indentation measurements, presenting an example of nanoindentation and scratch test simulations. To reach these purposes, three-dimensional molecular dynamics (MD) simulations of nanoindentation and scratch test technique were carried out for generic thin films that present BCC crystalline structures. Structures were oriented in the plane (100) and placed on FCC diamond substrates. A pair wise potential was employed to simulate the interaction between atoms of each layer and a repulsive radial potential was used to represent a spherical tip indenting the sample. Mechanical properties of this generic material were obtained by varying the indentation depth and dissociation energy. The load-unload curves and coefficient of friction were found for each test; on the other hand, dissociation energy was varied showing a better mechanical response for films that present grater dissociation energy. Structural change evolution was observed presenting vacancies and slips as the depth was varied. Project supported by la DirecciónNacional de Investigación of the Universidad Nacional de Colombia, “the Theoretical Study of Physical Properties of Hard Materials for Technological Applications” (Grant No. 20101007903).

  17. The sex offender treatment intervention and progress scale (SOTIPS): psychometric properties and incremental predictive validity with static-99R.

    McGrath, Robert J; Lasher, Michael P; Cumming, Georgia F

    2012-10-01

    The Sex Offender Treatment Intervention and Progress Scale (SOTIPS) is a 16-item rating scale designed to assess dynamic risk among adult male sex offenders and degree of change at 6-month intervals during treatment. The purpose of the present study was to examine the psychometric properties of the SOTIPS in a construction sample of 759 adult male sex offenders who were under correctional supervision and enrolled in cognitive-behavioral community treatment in Vermont between 2001 and 2007. The scale showed acceptable interrater reliability. SOTIPS scores at 1, 7, and 13 months after participants began treatment predicted sexual, violent, and any recidivism, and return to prison at fixed 1- and 3-year follow-up periods (AUCs = .60 to .85). Combined SOTIPS and Static-99R scores predicted all recidivism types (AUCs = .67 to .89) and outperformed either instrument alone when both instruments had similar predictive power. Participants who demonstrated treatment progress, as reflected by reductions in SOTIPS scores, showed lower rates of recidivism than those who did not. PMID:22368161

  18. Psychometric properties of the Spanish version of the mindful attention awareness scale (MAAS in patients with fibromyalgia

    Cebolla Ausias

    2013-01-01

    Full Text Available Abstract Background Mindful-based interventions improve functioning and quality of life in fibromyalgia (FM patients. The aim of the study is to perform a psychometric analysis of the Spanish version of the Mindful Attention Awareness Scale (MAAS in a sample of patients diagnosed with FM. Methods The following measures were administered to 251 Spanish patients with FM: the Spanish version of MAAS, the Chronic Pain Acceptance Questionnaire, the Pain Catastrophising Scale, the Injustice Experience Questionnaire, the Psychological Inflexibility in Pain Scale, the Fibromyalgia Impact Questionnaire and the Euroqol. Factorial structure was analysed using Confirmatory Factor Analyses (CFA. Cronbach's α coefficient was calculated to examine internal consistency, and the intraclass correlation coefficient (ICC was calculated to assess the test-retest reliability of the measures. Pearson’s correlation tests were run to evaluate univariate relationships between scores on the MAAS and criterion variables. Results The MAAS scores in our sample were low (M = 56.7; SD = 17.5. CFA confirmed a two-factor structure, with the following fit indices [sbX2 = 172.34 (p  Conclusion Psychometric properties of the Spanish version of the MAAS in patients with FM are adequate. The dimensionality of the MAAS found in this sample and directions for future research are discussed.

  19. The MUSIC of Galaxy Clusters - III. Properties, evolution and Y-M scaling relation of protoclusters of galaxies

    Sembolini, Federico; De Petris, Marco; Yepes, Gustavo; Foschi, Emma; Lamagna, Luca; Gottlöber, Stefan

    2014-06-01

    In this work, we study the properties of protoclusters of galaxies by employing the MultiDark SImulations of galaxy Clusters (MUSIC) set of hydrodynamical simulations, featuring a sample of 282 resimulated clusters with available merger trees up to z = 4. We study the characteristics and redshift evolution of the mass and the spatial distribution for all the protoclusters, which we define as the most massive progenitors of the clusters identified at z = 0. We extend the study of the baryon content to redshifts larger than 1 also in terms of gas and stars budgets: no remarkable variations with redshift are discovered. Furthermore, motivated by the proven potential of Sunyaev-Zel'dovich surveys to blindly search for faint distant objects, we compute the scaling relation between total object mass and integrated Compton y-parameter. We find that the slope of this scaling law is steeper than what expected for a self-similarity assumption among these objects, and it increases with redshift mainly when radiative processes are included. We use three different criteria to account for the dynamical state of the protoclusters, and find no significant dependence of the scaling parameters on the level of relaxation. We exclude the dynamical state as the cause of the observed deviations from self-similarity in protoclusters.

  20. A weak gravitational lensing recalibration of the scaling relations linking the gas properties of dark haloes to their mass

    Wang, Wenting; White, Simon D. M.; Mandelbaum, Rachel; Henriques, Bruno; Anderson, Michael E.; Han, Jiaxin

    2016-03-01

    We use weak gravitational lensing to measure mean mass profiles around locally brightest galaxies (LBGs). These are selected from the Seventh Data Release of the Sloan Digital Sky Survey spectroscopic and photometric catalogues to be brighter than any neighbour projected within 1.0 Mpc and differing in redshift by 83 per cent) are expected to be the central galaxies of their dark matter haloes. Previous stacking analyses have used this LBG sample to measure mean Sunyaev-Zeldovich flux and mean X-ray luminosity as a function of LBG stellar mass. In both cases, a simulation of the formation of the galaxy population was used to estimate effective halo mass for LBGs of given stellar mass, allowing the derivation of scaling relations between the gas properties of haloes and their mass. By comparing results from a variety of simulations to our lensing data, we show that this procedure has significant model dependence reflecting: (i) the failure of any given simulation to reproduce observed galaxy abundances exactly; (ii) a dependence on the cosmology underlying the simulation; and (iii) a dependence on the details of how galaxies populate haloes. We use our lensing results to recalibrate the scaling relations, eliminating most of this model dependence and explicitly accounting both for residual modelling uncertainties and for observational uncertainties in the lensing results. The resulting scaling relations link the mean gas properties of dark haloes to their mass over an unprecedentedly wide range, 1012.5 < M500/M⊙ < 1014.5, and should fairly and robustly represent the full halo population.

  1. Effects of Scale-Free Topological Properties on Dynamical Synchronization and Control in Coupled Map Lattices

    CHEN Wei; FANG Jin-Qing; KANG Ge-Wen

    2007-01-01

    In the paper,we study effects of scale-free (SF) topology on dynamical synchronization and control in coupled map lattices (CML).Our strategy is to apply three feedback control methods,including constant feedback and two types of time-delayed feedback,to a small fraction of network nodes to reach desired synchronous state.Two controlled bifurcation diagrams verses feedback strength are obtained respectively.It is found that the value of critical feedback strength γc for the first time-delayed feedback control is increased linearly as ε is increased linearly.The CML with SF loses synchronization and intermittency occurs if γ,>γc.Numerical examples are presented to demonstrate all results.

  2. Commercial Properties, Properties assessed as commercial can be extracted from the tax roll and used in conjunction with the graphic cadastral dataset., Published in 2013, 1:2400 (1in=200ft) scale, Washington County Planning and Parks Department.

    NSGIC GIS Inventory (aka Ramona) — This Commercial Properties dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Published Reports/Deeds information as of 2013. It is...

  3. Pore-scale analysis of electrical properties in thinly bedded rock using digital rock physics

    We investigated the electrical properties of laminated rock consist of macro-porous layers and micro-porous layers based on digital rock technology. Due to the bedding effect and anisotropy, traditional Archie equations cannot well describe the electrical behavior of laminated rock. The RI-Sw curve of laminated rock shows a nonlinear relationship. The RI-Sw curve can be divided into two linear segments with different saturation exponent. Laminated sand-shale sequences and laminated sands of different porosity or grain size will yield macroscopic electrical anisotropy. Numerical simulation and theoretical analysis lead to the conclusion that electrical anisotropy coefficient of laminated rock is a strong function of water saturation. The function curve can be divided into three segments by the turning point. Therefore, the electrical behavior of laminated rock should be considered in oil exploration and development. (paper)

  4. Microstructure-dependent mechanical properties of electrospun core-shell scaffolds at multi-scale levels.

    Horner, Christopher B; Ico, Gerardo; Johnson, Jed; Zhao, Yi; Nam, Jin

    2016-06-01

    Mechanical factors among many physiochemical properties of scaffolds for stem cell-based tissue engineering significantly affect tissue morphogenesis by controlling stem cell behaviors including proliferation and phenotype-specific differentiation. Core-shell electrospinning provides a unique opportunity to control mechanical properties of scaffolds independent of surface chemistry, rendering a greater freedom to tailor design for specific applications. In this study, we synthesized electrospun core-shell scaffolds having different core composition and/or core-to-shell dimensional ratios. Two independent biocompatible polymer systems, polyetherketoneketone (PEKK) and gelatin as the core materials while maintaining the shell polymer with polycaprolactone (PCL), were utilized. The mechanics of such scaffolds was analyzed at the microscale and macroscales to determine the potential implications it may hold for cell-material and tissue-material interactions. The mechanical properties of individual core-shell fibers were controlled by core-shell composition and structure. The individual fiber modulus correlated with the increase in percent core size ranging from 0.55±0.10GPa to 1.74±0.22GPa and 0.48±0.12GPa to 1.53±0.12GPa for the PEKK-PCL and gelatin-PCL fibers, respectively. More importantly, it was demonstrated that mechanical properties of the scaffolds at the macroscale were dominantly determined by porosity under compression. The increase of scaffold porosity from 70.2%±1.0% to 93.2%±0.5% by increasing the core size in the PEKK-PCL scaffold resulted in the decrease of the compressive elastic modulus from 227.67±20.39kPa to 14.55±1.43kPa while a greater changes in the porosity of gelatin-PCL scaffold from 54.5%±4.2% to 89.6%±0.4% resulted in the compressive elastic modulus change from 484.01±30.18kPa to 17.57±1.40kPa. On the other hand, the biphasic behaviors under tensile mechanical loading result in a range from a minimum of 5.42±1.05MPa to a maximum

  5. Atomic scale understanding of magnetic properties in Ni50Fe35Co15

    L. Herojit Singh

    2016-02-01

    Full Text Available Mössbauer spectroscopic studies have been carried out at different temperatures across ferromagnetic to paramagnetic transition in Ni50Fe35Co15 and the evolution of hyperfine parameters such as centre shift and magnetic hyperfine fields with temperature has been studied. Mössbauer spectrum obtained at 300 K in Ni50Fe35Co15 exhibiting fcc crystal structure is a six line pattern with the mean value of the hyperfine field close to 33 Tesla. Ferromagnetic to paramagnetic transition has been observed to occur in this system around 895 K matching with that of magnetization results. Debye temperature of this nickel rich alloy is deduced to be around 470 K matching with that of Ni. Effect of prolonged annealing at 750 K on the magnetic property is also investigated with respect to the thermal stability of the alloy .

  6. Atomic scale understanding of magnetic properties in Ni50Fe35Co15

    Herojit Singh, L.; Govindaraj, R.; Ravishankar, C.; Rajagopalan, S.; Amarendra, G.

    2016-02-01

    Mössbauer spectroscopic studies have been carried out at different temperatures across ferromagnetic to paramagnetic transition in Ni50Fe35Co15 and the evolution of hyperfine parameters such as centre shift and magnetic hyperfine fields with temperature has been studied. Mössbauer spectrum obtained at 300 K in Ni50Fe35Co15 exhibiting fcc crystal structure is a six line pattern with the mean value of the hyperfine field close to 33 Tesla. Ferromagnetic to paramagnetic transition has been observed to occur in this system around 895 K matching with that of magnetization results. Debye temperature of this nickel rich alloy is deduced to be around 470 K matching with that of Ni. Effect of prolonged annealing at 750 K on the magnetic property is also investigated with respect to the thermal stability of the alloy .

  7. Atomic scale understanding of magnetic properties in Ni50Fe35Co15

    Mössbauer spectroscopic studies have been carried out at different temperatures across ferromagnetic to paramagnetic transition in Ni50Fe35Co15 and the evolution of hyperfine parameters such as centre shift and magnetic hyperfine fields with temperature has been studied. Mössbauer spectrum obtained at 300 K in Ni50Fe35Co15 exhibiting fcc crystal structure is a six line pattern with the mean value of the hyperfine field close to 33 Tesla. Ferromagnetic to paramagnetic transition has been observed to occur in this system around 895 K matching with that of magnetization results. Debye temperature of this nickel rich alloy is deduced to be around 470 K matching with that of Ni. Effect of prolonged annealing at 750 K on the magnetic property is also investigated with respect to the thermal stability of the alloy

  8. Atomic-scale simulation of nano-grains:structure and diffusion properties

    2003-01-01

    Nanograins are characterized by a typical grain size from 1 to 100 nm. Molecular dynamics simulations have been carried out for the nanograin sphere with the diameters from 1.45 to 10.12 nm. We study the influence of grain size on structure and diffusion properties of the nanograins. The results reveal that as the grain size is reduced, the fraction of grain surface increases significantly, and the surface width is approximately constant; the mean atomic energy of the surface increases distinctly, but that of the grain interior varies insignificantly; the diffusion coefficient is increased sharply, and the relation of the diffusion coefficient and the grain size is close to exponential relation below 10 nm.

  9. Psychometric Properties and Validation of the Arabic Social Media Addiction Scale

    Jamal Al-Menayes

    2015-01-01

    Full Text Available This study investigated the psychometric properties of the Arabic version of the SMAS. SMAS is a variant of IAT customized to measure addiction to social media instead of the Internet as a whole. Using a self-report instrument on a cross-sectional sample of undergraduate students, the results revealed the following. First, the exploratory factor analysis showed that a three-factor model fits the data well. Second, concurrent validity analysis showed the SMAS to be a valid measure of social media addiction. However, further studies and data should verify the hypothesized model. Finally, this study showed that the Arabic version of the SMAS is a valid and reliable instrument for use in measuring social media addiction in the Arab world.

  10. Cross-Wind Modal Properties of Offshore Wind Turbines Identified by Full Scale Testing

    Damgaard, Mads; Ibsen, Lars Bo; Andersen, Lars Vabbersgaard; K. F. Andersen, Jacob

    Cross-wind vibrations due to wave loading misaligned with wind turbulence are often a design driver for offshore wind turbine foundations. The phenomenon is characterised by increasing fatigue loads compared to the fore-aft fatigue and a small amount of system damping since almost no aerodynamic...... damping from the blades takes place. In addition, modern offshore wind turbines are flexible structures with resonance frequencies close to environmental loads and turbine blades passing the tower. Therefore, in order to avoid conservatism during the load calculation and the design phase leading to...... additional costs, the structural response must be analysed with reliable estimations of the dynamic properties of the wind turbines. Based on a thorough investigation of “rotor-stop” tests performed on offshore wind turbines supported by a monopile foundation for different wind parks in the period 2006...

  11. Leaf hydraulics I: scaling transport properties from single cells to tissues.

    Rockwell, Fulton E; Michele Holbrook, N; Stroock, Abraham D

    2014-01-01

    In leaf tissues, water may move through the symplast or apoplast as a liquid, or through the airspace as vapor, but the dominant path remains in dispute. This is due, in part, to a lack of models that describe these three pathways in terms of experimental variables. We show that, in plant water relations theory, the use of a hydraulic capacity in a manner analogous to a thermal capacity, though it ignores mechanical interactions between cells, is consistent with a special case of the more general continuum mechanical theory of linear poroelasticity. The resulting heat equation form affords a great deal of analytical simplicity at a minimal cost: we estimate an expected error of less than 12%, compared to the full set of equations governing linear poroelastic behavior. We next consider the case for local equilibrium between protoplasts, their cell walls, and adjacent air spaces during isothermal hydration transients to determine how accurately simple volume averaging of material properties (a 'composite' model) describes the hydraulic properties of leaf tissue. Based on typical hydraulic parameters for individual cells, we find that a composite description for tissues composed of thin walled cells with air spaces of similar size to the cells, as in photosynthetic tissues, is a reasonable preliminary assumption. We also expect isothermal transport in such cells to be dominated by the aquaporin-mediated cell-to-cell path. In the non-isothermal case, information on the magnitude of the thermal gradients is required to assess the dominant phase of water transport, liquid or vapor. PMID:24112968

  12. Properties of internal planetary-scale inertio gravity waves in the mesosphere

    H. G. Mayr

    2004-11-01

    Full Text Available At high latitudes in the upper mesosphere, horizontal wind oscillations have been observed with periods around 10h. Waves with such a period are generated in our Numerical Spectral Model (NSM, and they are identified as planetary-scale inertio gravity waves (IGW. These IGWs have periods between 9 and 11h and appear above 60km in the zonal mean (m=0, as well as in m=1 to 4, propagating eastward and westward. Under the influence of the Coriolis force, the amplitudes of the waves propagating westward are larger at high latitudes than those propagating eastward. The waves grow in magnitude at least up to about 100km and have vertical wavelengths around 25km. Applying a running window of 15 days for spectral analysis, the amplitudes in the wind field are typically between 10 and 20m/s and can reach 30m/s in the westward propagating component for m=1 at the poles. In the temperature perturbations, the wave amplitudes above 100km are typically 5K and as large as 10K for m=0 at the poles. The IGWs are intermittent but reveal systematic seasonal variations, with the largest amplitudes occurring generally in late winter and spring. Numerical experiments show that such waves are also generated without excitation of the migrating tides. The amplitudes and periods then are similar, indicating that the tides are not essential to generate the waves. However, the seasonal variations without tides are significantly different, which leads to the conclusion that non linear interactions between the semidiurnal tide and planetary waves must contribute to the excitation of the IGWs. Directly or indirectly through the planetary waves, the IGWs are apparently excited by the instabilities that arise in the zonal mean circulation. When the solar heating is turned off for m=0, both the PWs and IGWs essentially disappear. That the IGWs and PWs have common roots in their excitation mechanism is also indicated by the striking similarity of their seasonal variations in the

  13. Effects of electric field on micro-scale flame properties of biobutanol fuel.

    Xu, Tao; Chen, Qinglin; Zhang, Bingjian; Lu, Shushen; Mo, Dongchuan; Zhang, Zhengguo; Gao, Xuenong

    2016-01-01

    With the increasing need of smaller power sources for satellites, energy systems and engine equipment, microcombustion pose a potential as alternative power source to conventional batteries. As the substitute fuel source for gasoline, biobutanol shows more promising characteristics than ethanol. In this study, the diffusion microflame of liquid biobutanol under electric field have been examined through in-lab experiment and numerical simulation. It is found that traditional gas jet diffusion flame theory shows significant inconsistency with the experimental results of micro scale flame in electric field. The results suggest that with the increase of electric field intensity, the quenching flow rate decrease first and increase after it reach its minimum, while the flame height and highest flame temperature increase first and drop after its peak value. In addition, it was also observed that the flame height and highest temperature for smaller tube can reach its maximum faster. Therefore, the interaction between microscale effect and electric field plays a significant role on understanding the microcombustion of liquid fuel. Therefore, FLUENT simulation was adopted to understand and measure the impacts of microflame characteristic parameters. The final numerical results are consistent with the experimental data and show a high reliability. PMID:27609428

  14. Validation and Psychometric Properties of Mobile Phone Problematic Use Scale (MPPUS in University Students of Tehran.

    Soroush Mohammadi Kalhori

    2015-03-01

    Full Text Available Despite the fact that the mobile phone has become a pervasive technology of our time, little research has been done on mobile dependency. Therefore, a valid and reliable instrument, conforming to Iranian culture seems essential. The aim of our study was to validate the Iranian version of MPPUS (Mobile Phone Problematic Use Scale.This was a cross-sectional research, in which data were collected from 600 students studying at Tehran universities. Stratified sampling method was used to collect data. All participants completed Demographic Questionnaire, Cellular Phone Dependency Questionnaire (CPDQ anonymously. Finally, a clinical interview (based on DSM-IV-TR was conducted with 100 participants. Data were analyzed using concurrent validity, factor analysis, internal consistency (Cronbach's'α, split half, test-retest and ROC Curve by SPSS18 Software.As a result of reliability analysis and factor analysis by principal component and Varimax rotation, we extracted three factors including preoccupation, withdrawal symptoms and overuse of mobile phones in both males and females. Internal consistency (Cronbach's alpha of the MPPUS was .91; Cronbach's alpha of the factors was .87, .70, .82 respectively. The test-retest correlation of the MPPUS was .56. The best cut off point for this questionnaire (MPPUS was 160.The MPPUS proved to be a reliable questionnaire with adequate factor models to assess the extent of problems caused by the "misuse" of mobile phones in the Iranian society; however, further studies are needed on this topic.

  15. The effects of smoothing on the statistical properties of the large-scale cosmic fields

    Bernardeau, F

    1994-01-01

    It has been shown that the large--scale correlation functions of the density field (and velocity divergence field) follow a specific hierarchy in the quasilinear regime and for Gaussian initial conditions (Bernardeau 1992). The exact relationships between the cumulants of the probability distribution functions (the so-called S_p parameters) are however sensitive to the smoothing window function applied to the fields. In this paper, I present a method to derive the whole series of the S_p parameters when the density field is smoothed with a top--hat window function. The results are valid for any power spectrum and any cosmological parameters. Similar calculations are presented for the velocity divergence field. The resulting shapes of the one--point probability distribution functions of the cosmic density and the velocity divergence fields are given as a function of the power spectrum and \\Omega. Simple analytical fits are proposed when the index of the power spectrum is -1. Comparisons with numerical simulati...

  16. Investigation of scaling properties of a thin current sheet by means of particle trajectories study

    Sasunov, Yu L; Alexeev, I I; Belenkaya, E S; Semenov, V S; Kubyshkin, I V; Mingalev, O V

    2015-01-01

    A thin current sheet (TCS), with the width of an order of thermal proton gyroradius, appears a fundamental physical object which plays an important role in structuring of major magnetospheric current systems (magnetotail, magnetodisk, etc.). The TCSs are nowadays under extensive study by means of space missions and theoretical models. We consider a simple model of the TCS separating two half-spaces occupied by a homogenous magnetic field of opposite sign tangential to the TCS; a small normal component of the magnetic field is prescribed. An analytical solution for the electric current and plasma density in the close vicinity of the TCS has been obtained and compared with numerical simulation. The number density and the electric current profiles have two maxima each. The characteristic spatial scale $z_S$ of the maxima location was investigated as a function of initial pitch-angle of an incoming charge particle. The effect of the thermal dispersion of the incoming proton beam have been taken into consideration...

  17. The generalised anxiety stigma scale (GASS: psychometric properties in a community sample

    Griffiths Kathleen M

    2011-11-01

    Full Text Available Abstract Background Although there is substantial concern about negative attitudes to mental illness, little is known about the stigma associated with Generalised Anxiety Disorder (GAD or its measurement. The aim of this study was to develop a multi-item measure of Generalised Anxiety Disorder stigma (the GASS. Methods Stigma items were developed from a thematic analysis of web-based text about the stigma associated with GAD. Six hundred and seventeen members of the public completed a survey comprising the resulting 20 stigma items and measures designed to evaluate construct validity. Follow-up data were collected for a subset of the participants (n = 212. Results The factor structure comprised two components: Personal Stigma (views about Generalised Anxiety Disorder; and Perceived Stigma (views about the beliefs of most others in the community. There was evidence of good construct validity and reliability for each of the Generalised Anxiety Stigma Scale (GASS subscales. Conclusions The GASS is a promising brief measure of the stigma associated with Generalised Anxiety Disorder.

  18. Specimen Size Effects on Mechanical Properties of Small-scale Mechanical Testing

    In this study, the specimen size effects on the yield stress are systematically investigated for a bulk metastable austenitic alloy with grain sizes of 0.3, 0.6, and 2 mm. Microcompression tests have been performed on micropillars with a diameter ranging from 0.6 to 18 mm, which enables a wide range of the specimen to grain size ratio (D/d) of 0.5∼30 to be studied. The yield stresses were found to decrease with decreasing specimen size, especially when D/d is below a critical value. The critical value was decreasing function of grain size and the density of lattice defects. Care should be taken when determining micropillar size to evaluate bulk mechanical properties for nanocrystalline materials, since the critical D/d value is increasing with decreasing grain size and the weakening is more pronounced in micropillar than flat tensile specimen geometry. The stresses were found to decrease with decreasing specimen size when the value of the specimen size (s) divided by material's grain size (d) becomes smaller than a critical value. Note that s/d is approximately the number of grains across the specimen size. In practical viewpoint, the value of the critical size is of primary interest in order to determine the specimen size for obtaining bulk mechanical properties. The accumulated experimental results for size-induced weakening suggest that critical values of a material depend on grain size, specimen geometry and stacking fault energy. In other words, critical values for weakening is a complex function of intrinsic (microstructure, stacking fault energy) and extrinsic (specimen geometry) effects. While the dependence of the critical values on the intrinsic or extrinsic parameter of a specimen is evident, systematic studies to date have been limited. In this study, size effects on yield stresses are investigated for microcompression tests of a metastable bulk austenitic alloy with the pillar diameter to grain size ratio in a wide range from 0.5 to 30. The

  19. Nursing students' attitudes to mental health nursing: psychometric properties of a self-report scale.

    Happell, Brenda; Hayman-White, Karla Gough Nee

    2009-10-01

    Negative attitudes toward people experiencing mental illness and mental health nursing as a career option have been recognized as a major barrier to sustaining an adequate psychiatric nursing workforce. This article presents the findings from a prospective observational study that explored the relationship between undergraduate nursing students' (n = 688) attitudes relevant to the mental health field, preparedness, and career preferences after they had completed a mental health placement. A comparison was also made between the self-reported attitudes, beliefs, and preferences of two groups of students, one with and one without relevant clinical experience. Finally, the psychometric properties of the clinical evaluation component of the survey were explored because the structure and composition of this component have not been assessed or reported previously. The findings have direct implications for psychiatric-mental health education. They show a strong association between educational preparation, placement experiences, and students' attitudes toward psychiatric nursing and consumers of mental health services. Findings also indicated that students with clinical experience felt significantly more prepared for employment in the mental health field and significantly less anxiety surrounding mental illness than did students without clinical experience. PMID:19766929

  20. Surface tracks on polymers: A means to probe material properties at the nanometer scale?

    The morphology and the dimensions of nanometer-sized craters and crater rims induced by individual MeV heavy ions impacting polymer surfaces have been systematically investigated by means of scanning force microscopy. We demonstrate that the morphology of the surface tracks varies systematically with temperature, molecular weight (Mw) and tacticity of polymer thin films. Such parameters influence chain mobility and the characteristic relaxation times of the polymer, which appear to be key factors determining the final shape and size of observed holes and hillocks. Because of the correlation of the impact features with the thermal and rheological properties of polymers, the problem can be inverted and the surface track morphology may be used to identify physical parameters of the targets. This procedure has been applied to model polymer films. It was possible to identify a critical target temperature above which a sharp change in crater morphology is observed in the scanning force microscopy images. We propose this temperature to be the glass transition temperature. Also, crater size decreases steeply with increasing molecular weight up to a critical Mw above which crater dimensions change very little. The transition region is around Mc', the critical molecular weight at which entanglement coupling of macromolecular chains becomes important

  1. AME - Asteroseismology Made Easy. Estimating stellar properties by use of scaled models

    Lundkvist, M; Aguirre, V Silva

    2014-01-01

    We present a new method to obtain stellar properties for stars exhibiting solar-like oscillations in an easy, fast, and transparent way. The method, called Asteroseismology Made Easy (AME), can determine stellar masses, mean-densities, radii, and surface gravities, as well as estimate ages. In this writing we present AME as a visual and powerful tool which could be useful; in particular in the light of the large number of exoplanets being found. AME consists of a set of figures from which the stellar parameters are deduced. These figures are made from a grid of stellar evolutionary models that cover masses ranging from 0.7 Msun to 1.6 Msun in steps of 0.1 Msun and metallicities in the interval -0.3 dex <= [Fe/H] <= +0.3 dex in increments of 0.1 dex. The stellar evolutionary models are computed using the Modules for Experiments in Stellar Astrophysics (MESA) code with simple input physics. We have compared the results from AME with results for three groups of stars; stars with radii determined from inter...

  2. Differences in Human Cortical Gene Expression Match the Temporal Properties of Large-Scale Functional Networks

    Cioli, Claudia; Abdi, Hervé; Beaton, Derek; Burnod, Yves; Mesmoudi, Salma

    2014-01-01

    We explore the relationships between the cortex functional organization and genetic expression (as provided by the Allen Human Brain Atlas). Previous work suggests that functional cortical networks (resting state and task based) are organized as two large networks (differentiated by their preferred information processing mode) shaped like two rings. The first ring–Visual-Sensorimotor-Auditory (VSA)–comprises visual, auditory, somatosensory, and motor cortices that process real time world interactions. The second ring–Parieto-Temporo-Frontal (PTF)–comprises parietal, temporal, and frontal regions with networks dedicated to cognitive functions, emotions, biological needs, and internally driven rhythms. We found–with correspondence analysis–that the patterns of expression of the 938 genes most differentially expressed across the cortex organized the cortex into two sets of regions that match the two rings. We confirmed this result using discriminant correspondence analysis by showing that the genetic profiles of cortical regions can reliably predict to what ring these regions belong. We found that several of the proteins–coded by genes that most differentiate the rings–were involved in neuronal information processing such as ionic channels and neurotransmitter release. The systematic study of families of genes revealed specific proteins within families preferentially expressed in each ring. The results showed strong congruence between the preferential expression of subsets of genes, temporal properties of the proteins they code, and the preferred processing modes of the rings. Ionic channels and release-related proteins more expressed in the VSA ring favor temporal precision of fast evoked neural transmission (Sodium channels SCNA1, SCNB1 potassium channel KCNA1, calcium channel CACNA2D2, Synaptotagmin SYT2, Complexin CPLX1, Synaptobrevin VAMP1). Conversely, genes expressed in the PTF ring favor slower, sustained, or rhythmic activation (Sodium

  3. Enhancing the tensile properties of continuous millimeter-scale carbon nanotube fibers by densification.

    Hill, Frances A; Havel, Timothy F; Hart, A John; Livermore, Carol

    2013-08-14

    This work presents a study of the tensile mechanical properties of millimeter-long fibers comprising carbon nanotubes (CNTs). These CNT fibers are made of aligned, loosely packed parallel networks of CNTs that are grown in and harvested from CNT forests without drawing or spinning. Unlike typical CNT yarn, the present fibers contain a large fraction of CNTs that span the fibers' entire gauge length. The fibers are densified after growth and network formation to study how increasing the degree of interaction among CNTs in a network by various methods influences and limits the mechanical behavior of macroscopic CNT materials, particularly for the case in which the continuity of a large fraction of CNTs across the gauge length prevents failure purely by slip. Densification is carried out using various combinations of capillary-driven densification, mechanical pressure, and twisting. All methods of densification increase the fiber density and modify the nanoscale order of the CNTs. The highest strength and stiffness values (1.8 and 88.7 N tex(-1), respectively) are observed for capillary-densified fibers, whereas the highest toughness values (94 J g(-1)) and maximum reversible energy density (1.35 kJ kg(-1) or 677 kJ m(-3)) are observed for fibers densified by mechanical pressure. The results suggest that the path to higher performance CNT materials may lie not only in the use of continuous and long CNTs but also in controlling their density and nanoscale ordering through modification of the as-grown networks, such as by capillary-driven densification. PMID:23876225

  4. Atomic-scale simulation study of some bulk and interfacial properties of iron aluminium ordered alloys

    A semi-empirical potential was designed for B2 and DO3 iron aluminides and used to study point defects and grain boundaries in these compounds. At low temperature, departure from B2 stoichiometry is accommodated with antisite defects; when T increases, iron vacancies appear and defects have a trend to form clusters, the structure of which is very sensitive to this departure. Our calculations, relying on T = 0 K formation energies, predict the nature of major defects, but lead to underestimated quantitative results, which may point out the essential role of atomic vibrations. In the stoichiometric B2 compound, the diffusion of both species is induced by four-jump cycles involving iron vacancies. Although the agreement between our calculated activation energies and other experiments is good, the calculated diffusion coefficients are below the experimental ones. Here again, this discrepancy may be put down to the overlooking of phonon contributions. The second application concerns the atomic structures of the [001] (310) symmetric tilt grain boundary in the B2 and DO3 compounds. At low temperature, in the stoichiometric B2 compound, we obtain an iron-rich single stable structure (pseudo-symmetric), whose structure is strongly influenced by the bulk composition (with intergranular segregation of the major element). In the stoichiometric DO3 compound, many energetically equivalent structures exist, all being systematically aluminium-rich. The study of the B2 grain boundary structure at high temperature shows a phase transition favouring a symmetric structure. Its high excess energy at low temperature emphasizes the influence of atomic vibrations in the interfacial properties of B2 Fe-Al compounds. (author)

  5. Bayesian estimation of the hydraulic and solute transport properties of a small-scale unsaturated soil column

    Moreira Paulo H. S.

    2016-03-01

    Full Text Available In this study the hydraulic and solute transport properties of an unsaturated soil were estimated simultaneously from a relatively simple small-scale laboratory column infiltration/outflow experiment. As governing equations we used the Richards equation for variably saturated flow and a physical non-equilibrium dual-porosity type formulation for solute transport. A Bayesian parameter estimation approach was used in which the unknown parameters were estimated with the Markov Chain Monte Carlo (MCMC method through implementation of the Metropolis-Hastings algorithm. Sensitivity coefficients were examined in order to determine the most meaningful measurements for identifying the unknown hydraulic and transport parameters. Results obtained using the measured pressure head and solute concentration data collected during the unsaturated soil column experiment revealed the robustness of the proposed approach.

  6. Pore-scale study of dissolution-induced changes in hydrologic properties of rocks with binary minerals

    Chen, Li; Viswanathan, Hari S; Tao, Wenquan

    2014-01-01

    A pore-scale numerical model for reactive transport processes based on the Lattice Boltzmann method is used to study the dissolution-induced changes in hydrologic properties of a fractured medium and a porous medium. The solid phase of both media consists of two minerals, and a structure reconstruction method called quartet structure generation set is employed to generate the distributions of both minerals. Emphasis is put on the effects of undissolved minerals on the changes of permeability and porosity under different Peclet and Damkohler numbers. The simulation results show porous layers formed by the undissolved mineral remain behind the dissolution reaction front. Due to the large flow resistance in these porous layers, the permeability increases very slowly or even remains at a small value although the porosity increases by a large amount. Besides, due to the heterogeneous characteristic of the dissolution, the chemical, mechanical and hydraulic apertures are very different from each other. Further, sim...

  7. Size effects of nano-scale pinning centers on the superconducting properties of YBCO single grains

    Moutalbi, Nahed, E-mail: nahed.moutalbi@yahoo.fr [Systems and Applied Mechanics Laboratory LASMAP, Polytechnic School of Tunisia, Rue El Kawarezmi La Marsa 743, Tunis (Tunisia); Noudem, Jacques G. [CRISMAT/CNRS, UCBN/ENSICAEN, 6 Bd Maréchal Juin, 14050 Caen (France); M’chirgui, Ali [Systems and Applied Mechanics Laboratory LASMAP, Polytechnic School of Tunisia, Rue El Kawarezmi La Marsa 743, Tunis (Tunisia)

    2014-08-15

    Highlights: • Al{sub 2}O{sub 3} nano- sized inclusions were added to YBCO bulk samples in order to pin vortices. • Two batches of nano-particles with different particle size distributions were employed. • Critical current density improvement is shown to depend on size of Al{sub 2}O{sub 3} nano-inclusions. - Abstract: High pinning superconductors are the most promising materials for power engineering. Their superconducting properties are governed by the microstructure quality and the vortex pinning behavior. We report on a study of the vortex pinning in YBa{sub 2}Cu{sub 3}O{sub 7−x} (YBCO) single grain with defects induced through the addition of insulating nano-particles. In order to improve the critical current density, YBCO textured bulk superconductors were elaborated using the Top Seeded Melt Texture and Growth process with different addition amounts of Al{sub 2}O{sub 3} nano-particles. Serving as strong pinning centers, 0.05% excess of Al{sub 2}O{sub 3} causes a significant enhancement of the critical current density J{sub c} under self field and in magnetic fields at 77 K. The enhanced flux pinning achieved with the low level of alumina nano-particles endorses the effectiveness of insulating nano-inclusions to induce effectives pinning sites within the superconducting matrix. On the other side, we focused on the effect of the size of pinning centers on the critical current density. This work was carried out using two batches of alumina nano-particles characterized by two different particle size distributions with mean diameters PSD{sub 1} = 20 nm and PSD{sub 2} = 2.27 μm. The matching effects of the observed pinning force density have been compared. The obtained results have shown that the flux pinning is closely dependent on the size of the artificial pinning centers. Our results suggest that the optimization of the size of the artificial pinning centers is crucial to a much better understanding of the pinning mechanisms and therefore to insure high

  8. Dynamical Family Properties and Dark Halo Scaling Relations of Giant Elliptical Galaxies

    Gerhard, Ortwin; Kronawitter, Andi; Saglia, R. P.; Bender, Ralf

    2001-04-01

    Based on a uniform dynamical analysis of the line-profile shapes of 21 mostly luminous, slowly rotating, and nearly round elliptical galaxies, we have investigated the dynamical family relations and dark halo properties of ellipticals. Our results include: (i) The circular velocity curves (CVCs) of elliptical galaxies are flat to within ~=10% for R>~0.2Re. (ii) Most ellipticals are moderately radially anisotropic; their dynamical structure is surprisingly uniform. (iii) Elliptical galaxies follow a Tully-Fisher (TF) relation with marginally shallower slope than spiral galaxies, and vmaxc~=300 km s-1 for an L*B galaxy. At given circular velocity, they are ~1 mag fainter in B and ~0.6 mag in R and appear to have slightly lower baryonic mass than spirals, even for the maximum M/LB allowed by the kinematics. (iv) The luminosity dependence of M/LB indicated by the tilt of the fundamental plane (FP) is confirmed. The tilt of the FP is not caused by dynamical or photometric nonhomology, although the latter might influence the slope of M/L versus L. It can also not be due only to an increasing dark matter fraction with L for the range of IMF currently discussed. It is, however, consistent with stellar population models based on published metallicities and ages. The main driver is therefore probably metallicity, and a secondary population effect is needed to explain the K-band tilt. (v) These results make it likely that elliptical galaxies have nearly maximal M/LB (minimal halos). (vi) Despite the uniformly flat CVCs, there is a spread in the luminous to dark matter ratio and in cumulative M/LB(r). Some galaxies have no indication for dark matter within 2Re, whereas for others we obtain local M/LB-values of 20-30 at 2Re. (vii) In models with maximum stellar mass, the dark matter contributes ~10%-40% of the mass within Re. Equal interior mass of dark and luminous matter is predicted at ~2-4Re. (viii) Even in these maximum stellar mass models, the halo core densities and

  9. Paradigmatic flow for small-scale magnetohydrodynamics: properties of the ideal case and the collision of current sheets.

    Lee, E; Brachet, M E; Pouquet, A; Mininni, P D; Rosenberg, D

    2008-12-01

    We propose two sets of initial conditions for magnetohydrodynamics (MHD) in which both the velocity and the magnetic fields have spatial symmetries that are preserved by the dynamical equations as the system evolves. When implemented numerically they allow for substantial savings in CPU time and memory storage requirements for a given resolved scale separation. Basic properties of these Taylor-Green flows generalized to MHD are given, and the ideal nondissipative case is studied up to the equivalent of 2048;{3} grid points for one of these flows. The temporal evolution of the logarithmic decrements delta of the energy spectrum remains exponential at the highest spatial resolution considered, for which an acceleration is observed briefly before the grid resolution is reached. Up to the end of the exponential decay of delta , the behavior is consistent with a regular flow with no appearance of a singularity. The subsequent short acceleration in the formation of small magnetic scales can be associated with a near collision of two current sheets driven together by magnetic pressure. It leads to strong gradients with a fast rotation of the direction of the magnetic field, a feature also observed in the solar wind. PMID:19256956

  10. Scale effects of nanomechanical properties and deformation behavior of Au nanoparticle and thin film using depth sensing nanoindentation.

    Maharaj, Dave; Bhushan, Bharat

    2014-01-01

    Nanoscale research of bulk solid surfaces, thin films and micro- and nano-objects has shown that mechanical properties are enhanced at smaller scales. Experimental studies that directly compare local with global deformation are lacking. In this research, spherical Au nanoparticles, 500 nm in diameter and 100 nm thick Au films were selected. Nanoindentation (local deformation) and compression tests (global deformation) were performed with a nanoindenter using a sharp Berkovich tip and a flat punch, respectively. Data from nanoindentation studies were compared with bulk to study scale effects. Nanoscale hardness of the film was found to be higher than the nanoparticles with both being higher than bulk. Both nanoparticles and film showed increasing hardness for decreasing penetration depth. For the film, creep and strain rate effects were observed. In comparison of nanoindentation and compression tests, more pop-ins during loading were observed during the nanoindentation of nanoparticles. Repeated compression tests of nanoparticles were performed that showed a strain hardening effect and increased pop-ins during subsequent loads. PMID:24991519

  11. Scale effects of nanomechanical properties and deformation behavior of Au nanoparticle and thin film using depth sensing nanoindentation

    Dave Maharaj

    2014-06-01

    Full Text Available Nanoscale research of bulk solid surfaces, thin films and micro- and nano-objects has shown that mechanical properties are enhanced at smaller scales. Experimental studies that directly compare local with global deformation are lacking. In this research, spherical Au nanoparticles, 500 nm in diameter and 100 nm thick Au films were selected. Nanoindentation (local deformation and compression tests (global deformation were performed with a nanoindenter using a sharp Berkovich tip and a flat punch, respectively. Data from nanoindentation studies were compared with bulk to study scale effects. Nanoscale hardness of the film was found to be higher than the nanoparticles with both being higher than bulk. Both nanoparticles and film showed increasing hardness for decreasing penetration depth. For the film, creep and strain rate effects were observed. In comparison of nanoindentation and compression tests, more pop-ins during loading were observed during the nanoindentation of nanoparticles. Repeated compression tests of nanoparticles were performed that showed a strain hardening effect and increased pop-ins during subsequent loads.

  12. Comparison of properties of small-scale ion flux fluctuations in the flank magnetosheath and in the solar wind

    Riazantseva, M. O.; Budaev, V. P.; Rakhmanova, L. S.; Zastenker, G. N.; Šafránková, J.; Němeček, Z.; Přech, L.

    2016-07-01

    We present a comparison of spectral and statistical properties of ion flux fluctuations in the turbulent solar wind and in the flank Earth's magnetosheath. We use the data of the BMSW device operating in frame of the SPECTR-R mission with an extremely high-time resolution (up to ∼30 ms). Fourier spectra of ion flux fluctuations are systematically analyzed both in the solar wind and in the magnetosheath on the inertial scale and on a transition to the dissipation scale in the range of 0.01-10 Hz. We show that ion flux fluctuation spectra in the flank magnetosheath are similar to those observed in the solar wind and we demonstrate the presence of the break at frequencies of ∼1-2 Hz. Spectra are slightly steeper in the flank magnetosheath but the break frequency is near twice less in a comparison to the solar wind. The magnetosheath ion flux turbulent flow is intermittent as it was shown earlier for the solar wind. We discuss the level of intermittency of ion flux fluctuations in both regions and we determine the characteristics of structure functions. Finally, we demonstrate extended self-similarity in the magnetosheath.

  13. Scaling and Fractal Properties of the Horizontal Geomagnetic Field at the Tropical Stations of Langkawi and Davao in February 2007

    Hamid, N. S. A.; Gopir, G.; Ismail, M.; Misran, N.; Usang, M. D.; Yumoto, K.

    2010-07-01

    We investigate the scaling and fractal properties of the horizontal component of the geomagnetic field time series acquired by the Magnetic Data Acquisition System (MAGDAS) of the Space Environment Research Center (SERC) of Kyushu University in Japan. The data set covers the quiet period of geomagnetic activity in February 2007 at the near equatorial stations of Langkawi in Malaysia and Davao in the Philippines. These data were sampled every minute for 28 days giving a sample size of 40,320. The power spectra of the time series are obtained, showing dominant periodicities at 24, 12, 8 and 6 hours due to the effect of the sun on the geomagnetic field. The power spectra also indicate scaling with Hurst exponents of 0.50-0.77 in the period of 10 minutes to 6 hours. Then, rescaled range analysis and detrended fluctuation analysis are performed, producing similar ranges of Hurst exponents. Finally, these fractal methods are used to determine the Hurst exponents of similar sized data sets artificially generated by a fractional Brownian motion. The results of this study indicate that the horizontal geomagnetic field at these stations are fractal in nature and persistent.

  14. Prediction of soil properties at farm-scale using factor analysis and model-based soil-sampling schemes

    Castro Franco, Mauricio; Costa, Jose Luis; Aparicio, Virginia

    2015-04-01

    Digital soil mapping techniques can be used for improve soil information at field-scale. The aim of this study were develop a RF model to soil organic matter (SOM) and clay content in top soil at farm-scale combining predictors reduction and model-based soil-sampling techniques. We combine predictors reduce by factor analysis and model-based soil-sampling schemes by Conditioned Latin hypercube sampling (cLHS) and Fuzzy c-means sampling (FCMS). In general, 11 of 18 predictors were selected. Factor analysis provided an efficient quantitative method to determine the number of predictors. The combination of cLHS and predictors reduction with factor analysis was effective to predict SOM and clay content. Factors related with vegetation cover and yield map were the most important predictors to predict SOM and clay content, whereas factors related with topography were the less important. A dataset minimum of 50 soil samples were necessary to demonstrate the efficacy of the combination Factor Analysis-cLHS-RF model. The accuracy of the RF models to predict SOM and clay content can be maximized by increasing the number of samples. In this study, we demonstrated that the combination Factor Analysis-cLHS could reduce the time and financial resources need to improve the predictive capacity of RF models to predict soil properties.

  15. AMiBA: Sunyaev-Zel'dovich effect derived properties and scaling relations of massive galaxy clusters

    Ho, Paul T P; Liu, Guo-Chin; Molnar, Sandor M; Nishioka, Hiroaki; Umetsu, Keiichi; Altamirano, Pablo; Birkinshaw, Mark; Chang, Chia-Hao; Chang, Shu-Hao; Chang, Su-Wei; Chen, Ming-Tang; Han, Chih-Chiang; Huang, Yau-De; Hwang, Yuh-Jing; Jiang, Homin; Kesteven, Michael; Kubo, Derek; Li, Chao-Te; Martin-Cocher, Pierre; Oshiro, Peter; Raffin, Philippe; Wei, Tashun; Wilson, Warwick

    2010-01-01

    The Sunyaev-Zel'dovich Effect (SZE) has been observed toward six massive galaxy clusters, at redshifts 0.091 \\leq z \\leq 0.322 in the 86-102 GHz band with the Y. T. Lee Array for Microwave Background Anisotropy (AMiBA). We modify an iterative method, based on the isothermal \\beta-models, to derive the electron temperature T_e, total mass M_t, gas mass M_g, and integrated Compton Y within r_2500, from the AMiBA SZE data. Non-isothermal universal temperature profile (UTP) \\beta models are also considered in this paper. These results are in good agreement with those deduced from other observations. We also investigate the embedded scaling relations, due to the assumptions that have been made in the method we adopted, between these purely SZE-deduced T_e, M_t, M_g and Y. Our results suggest that cluster properties may be measurable with SZE observations alone. However, the assumptions built into the pure-SZE method bias the results of scaling relation estimations and need further study.

  16. Scaling effect on the mid-diaphysis properties of long bones—the case of the Cervidae (deer)

    Amson, Eli; Kolb, Christian

    2016-08-01

    How skeletal elements scale to size is a fundamental question in biology. While the external shape of long bones was intensively studied, an important component of their organization is also found in their less accessible inner structure. Here, we studied mid-diaphyseal properties of limb long bones, characterizing notably the thickness of their cortices (bone walls), in order to test whether body size directly influences bone inner organization. Previous examinations of scaling in long bones used broad samplings to encompass a wide range of body sizes. To account for the effect of confounding factors related to different lifestyles, we focused our comprehensive sampling on a mammalian clade that comprises various body sizes but a relatively uniform lifestyle, the Cervidae. Positive allometry was found in femoral cross-sectional shape, indicating greater directional bending rigidity in large-sized taxa. None of the compactness parameters scaled allometrically in any of their bones. The cortices of sampled zeugopodial bones (tibia and radius) were found as significantly thicker than those of stylopodial bones (femur and humerus). Furthermore, while the mean relative cortical thickness values for both stylopodial and zeugopodial bones are close to mass-saving optima, the variance for the stylopodial bones is significantly lower. This suggests that mass saving is less intensively selected in zeugopodial bones. Finally, the long-legged Elk ( Alces) and the short-legged dwarf Cretan deer ( Candiacervus) featured rather thin and thick cortices, respectively, suggesting that the acquisition of a different limb proportion is accompanied by a modification of the relative mid-diaphyseal cortical thickness.

  17. Scaling effect on the mid-diaphysis properties of long bones-the case of the Cervidae (deer).

    Amson, Eli; Kolb, Christian

    2016-08-01

    How skeletal elements scale to size is a fundamental question in biology. While the external shape of long bones was intensively studied, an important component of their organization is also found in their less accessible inner structure. Here, we studied mid-diaphyseal properties of limb long bones, characterizing notably the thickness of their cortices (bone walls), in order to test whether body size directly influences bone inner organization. Previous examinations of scaling in long bones used broad samplings to encompass a wide range of body sizes. To account for the effect of confounding factors related to different lifestyles, we focused our comprehensive sampling on a mammalian clade that comprises various body sizes but a relatively uniform lifestyle, the Cervidae. Positive allometry was found in femoral cross-sectional shape, indicating greater directional bending rigidity in large-sized taxa. None of the compactness parameters scaled allometrically in any of their bones. The cortices of sampled zeugopodial bones (tibia and radius) were found as significantly thicker than those of stylopodial bones (femur and humerus). Furthermore, while the mean relative cortical thickness values for both stylopodial and zeugopodial bones are close to mass-saving optima, the variance for the stylopodial bones is significantly lower. This suggests that mass saving is less intensively selected in zeugopodial bones. Finally, the long-legged Elk (Alces) and the short-legged dwarf Cretan deer (Candiacervus) featured rather thin and thick cortices, respectively, suggesting that the acquisition of a different limb proportion is accompanied by a modification of the relative mid-diaphyseal cortical thickness. PMID:27350329

  18. Scale effects in tribological properties of solid-lubricating composites made of ultra-high molecular weight polyethylene filled with calcium stearate particles

    Lurie, S. A.; Volkov-Bogorodskiy, D. B.; Knyzeva, A. G.; Panin, S. V.; Kornienko, L. A.

    2016-04-01

    Friction properties being influenced by scale effects are simulated in the paper by the example of polymer composite material made from Ultra High-Molecular Weight Polyethylenes (UHMWPE) filled by calcium stearate (C36H70CaO4). Of interest are the composites whose mechanical properties and tribotechnical characteristics do not depend monotonically on filler (inclusions) weight fraction. In order to describe the influence of scale effects onto frictional properties the model based on Reiss averaging (model of "weak phase") is employed. It is also suggested that when gradient elasticity theory is applicable the formal analogy between effective friction coefficient for surface heterogeneous structures and effective mechanical properties (compliances) for heterogeneous material can take place. Theoretical dependence to describe nonmonotonic change of effective friction coefficient versus filler concentration was obtained for the polymer composites under study. The suggested expressions might be useful for the sake of properties prognosis of antifriction polymeric materilas.

  19. Large-Scale Synthesis and Systematic Photoluminescence Properties of Monolayer MoS2 on Fused Silica.

    Wan, Yi; Zhang, Hui; Zhang, Kun; Wang, Yilun; Sheng, Bowen; Wang, Xinqiang; Dai, Lun

    2016-07-20

    Monolayer MoS2, with fascinating mechanical, electrical, and optical properties, has generated enormous scientific curiosity and industrial interest. Controllable and scalable synthesis of monolayer MoS2 on various desired substrates has significant meaning in both basic scientific research and device application. Recent years have witnessed many advances in the direct synthesis of single-crystalline MoS2 flakes or their polycrystalline aggregates on numerous diverse substrates, such as SiO2-Si, mica, sapphire, h-BN, and SrTiO3, etc. In this work, we used the dual-temperature-zone atmospheric-pressure chemical vapor deposition method to directly synthesize large-scale monolayer MoS2 on fused silica, the most ordinary transparent insulating material in daily life. We systematically investigated the photoluminescence (PL) properties of monolayer MoS2 on fused silica and SiO2-Si substrates, which have different thermal conductivity coefficients and thermal expansion coefficients. We found that there exists a stronger strain on monolayer MoS2 grown on fused silica, and the strain becomes more obvious as temperature decreases. Moreover, the monolayer MoS2 grown on fused silica exhibits the unique trait of a fractal shape with tortuous edges and has stronger adsorbability. The monolayer MoS2 grown on fused silica may find application in sensing, energy storage, and transparent optoelectronics, etc. PMID:27338112

  20. Influence of nanometer scale film structure of ZDDP tribofilm on Its mechanical properties: A computational chemistry study

    We investigated the influence of a nanometer scale film structure of a tribofilm generated from zinc dialkyldithiophosphate (ZDDP) anti-wear additive on its mechanical properties using a combined molecular dynamics (MD) and finite element (FE) method. The frictional behavior of an interface between a native iron oxide layer on steel surface and zinc metaphosphate - regarded as a model material of ZDDP tribofilm - was firstly studied using the MD method. The results showed that the iron atoms in the oxide layer diffused into the phosphate layer during the friction process. The zinc atoms in the phosphate layer also diffused into the oxide layer. Significant interdiffusion of iron and zinc atoms was observed with increasing simulation time. Thus, metallic phosphate with a gradient composition of iron and zinc atoms was formed on the phosphate/oxide interface. We then constructed an axisymmetric nanoindentation simulation model from the MD-derived structures at a certain simulation time and carried out a FE calculation. As a result, we found that the rubbed ZDDP tribofilm, including the phosphate with the gradient composition of metallic atoms, showed larger contact stiffness and hardness. The combined MD/FE simulation indicates that the tribofilm becomes stiffer and harder due to the interdiffusion of iron and zinc atoms on the tribofilm/oxide interface. We have found that the gradient composition formation in ZDDP tribofilm during friction process influences on its mechanical properties.

  1. Spectral non-equilibrium property in homogeneous isotropic turbulence and its implication in subgrid-scale modeling

    Fang, Le [Laboratory of Mathematics and Physics, Ecole Centrale de Pékin, Beihang University, Beijing 100191 (China); Zhu, Ying [Laboratory of Mathematics and Physics, Ecole Centrale de Pékin, Beihang University, Beijing 100191 (China); National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics, School of Energy and Power Engineering, Beihang University, Beijing 100191 (China); Liu, Yangwei, E-mail: liuyangwei@126.com [National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics, School of Energy and Power Engineering, Beihang University, Beijing 100191 (China); Lu, Lipeng [National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics, School of Energy and Power Engineering, Beihang University, Beijing 100191 (China)

    2015-10-09

    The non-equilibrium property in turbulence is a non-negligible problem in large-eddy simulation but has not yet been systematically considered. The generalization from equilibrium turbulence to non-equilibrium turbulence requires a clear recognition of the non-equilibrium property. As a preliminary step of this recognition, the present letter defines a typical non-equilibrium process, that is, the spectral non-equilibrium process, in homogeneous isotropic turbulence. It is then theoretically investigated by employing the skewness of grid-scale velocity gradient, which permits the decomposition of resolved velocity field into an equilibrium one and a time-reversed one. Based on this decomposition, an improved Smagorinsky model is proposed to correct the non-equilibrium behavior of the traditional Smagorinsky model. The present study is expected to shed light on the future studies of more generalized non-equilibrium turbulent flows. - Highlights: • A spectral non-equilibrium process in isotropic turbulence is defined theoretically. • A decomposition method is proposed to divide a non-equilibrium turbulence field. • An improved Smagorinsky model is proposed to correct the non-equilibrium behavior.

  2. Determining Individual Phase Properties in a Multi-phase Q&P Steel using Multi-scale Indentation Tests

    Cheng, Guang; Choi, Kyoo Sil; Hu, Xiaohua; Sun, Xin

    2016-01-15

    A new inverse method was developed to predict the stress-strain behaviors of constituent phases in a multi-phase steel using the load-depth curves measured in nanoindentation tests combined with microhardness measurements. A power law hardening response was assumed for each phase, and an empirical relationship between hardness and yield strength was assumed. Adjustment was made to eliminate the indentation size effect and indenter bluntness effect. With the newly developed inverse method and statistical analysis of the hardness histogram for each phase, the average stress-strain curves of individual phases in a quench and partitioning (Q&P) steel, including austenite, tempered martensite and untempered martensite, were calculated and the results were compared with the phase properties obtained by in-situ high energy X-ray diffraction (HEXRD) test. It is demonstrated that multi-scale instrumented indentation tests together with the new inverse method are capable of determining the individual phase flow properties in multi-phase alloys.

  3. Influence of nanometer scale film structure of ZDDP tribofilm on Its mechanical properties: A computational chemistry study

    Onodera, Tasuku; Kuriaki, Takanori; Morita, Yusuke [Department of Applied Chemistry, Graduate School of Engineering, Tohoku University, 6-6-11-1302 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Suzuki, Ai [New Industry Creation Hatchery Center, Tohoku University, 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Koyama, Michihisa [Department of Chemical Engineering, Graduate School of Engineering, Tohoku University, 6-6-11-1302 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Tsuboi, Hideyuki; Hatakeyama, Nozomu; Endou, Akira [Department of Applied Chemistry, Graduate School of Engineering, Tohoku University, 6-6-11-1302 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Takaba, Hiromitsu [Department of Chemical Engineering, Graduate School of Engineering, Tohoku University, 6-6-11-1302 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Del Carpio, Carlos A. [Department of Applied Chemistry, Graduate School of Engineering, Tohoku University, 6-6-11-1302 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Kubo, Momoji [Fracture and Reliability Research Institute, Graduate School of Engineering, Tohoku University, 6-6-11-701 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Minfray, Clotilde; Martin, Jean-Michel [Laboratory of Tribology and Dynamical Systems, Ecole Centrale de Lyon, 36, avenue Guy de Collongue 69134, ECULLY Cedex (France); Miyamoto, Akira, E-mail: miyamoto@aki.che.tohoku.ac.jp [Department of Applied Chemistry, Graduate School of Engineering, Tohoku University, 6-6-11-1302 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); New Industry Creation Hatchery Center, Tohoku University, 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Department of Chemical Engineering, Graduate School of Engineering, Tohoku University, 6-6-11-1302 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan)

    2009-11-30

    We investigated the influence of a nanometer scale film structure of a tribofilm generated from zinc dialkyldithiophosphate (ZDDP) anti-wear additive on its mechanical properties using a combined molecular dynamics (MD) and finite element (FE) method. The frictional behavior of an interface between a native iron oxide layer on steel surface and zinc metaphosphate - regarded as a model material of ZDDP tribofilm - was firstly studied using the MD method. The results showed that the iron atoms in the oxide layer diffused into the phosphate layer during the friction process. The zinc atoms in the phosphate layer also diffused into the oxide layer. Significant interdiffusion of iron and zinc atoms was observed with increasing simulation time. Thus, metallic phosphate with a gradient composition of iron and zinc atoms was formed on the phosphate/oxide interface. We then constructed an axisymmetric nanoindentation simulation model from the MD-derived structures at a certain simulation time and carried out a FE calculation. As a result, we found that the rubbed ZDDP tribofilm, including the phosphate with the gradient composition of metallic atoms, showed larger contact stiffness and hardness. The combined MD/FE simulation indicates that the tribofilm becomes stiffer and harder due to the interdiffusion of iron and zinc atoms on the tribofilm/oxide interface. We have found that the gradient composition formation in ZDDP tribofilm during friction process influences on its mechanical properties.

  4. Influence of nanometer scale film structure of ZDDP tribofilm on Its mechanical properties: A computational chemistry study

    Onodera, Tasuku; Kuriaki, Takanori; Morita, Yusuke; Suzuki, Ai; Koyama, Michihisa; Tsuboi, Hideyuki; Hatakeyama, Nozomu; Endou, Akira; Takaba, Hiromitsu; Del Carpio, Carlos A.; Kubo, Momoji; Minfray, Clotilde; Martin, Jean-Michel; Miyamoto, Akira

    2009-11-01

    We investigated the influence of a nanometer scale film structure of a tribofilm generated from zinc dialkyldithiophosphate (ZDDP) anti-wear additive on its mechanical properties using a combined molecular dynamics (MD) and finite element (FE) method. The frictional behavior of an interface between a native iron oxide layer on steel surface and zinc metaphosphate - regarded as a model material of ZDDP tribofilm - was firstly studied using the MD method. The results showed that the iron atoms in the oxide layer diffused into the phosphate layer during the friction process. The zinc atoms in the phosphate layer also diffused into the oxide layer. Significant interdiffusion of iron and zinc atoms was observed with increasing simulation time. Thus, metallic phosphate with a gradient composition of iron and zinc atoms was formed on the phosphate/oxide interface. We then constructed an axisymmetric nanoindentation simulation model from the MD-derived structures at a certain simulation time and carried out a FE calculation. As a result, we found that the rubbed ZDDP tribofilm, including the phosphate with the gradient composition of metallic atoms, showed larger contact stiffness and hardness. The combined MD/FE simulation indicates that the tribofilm becomes stiffer and harder due to the interdiffusion of iron and zinc atoms on the tribofilm/oxide interface. We have found that the gradient composition formation in ZDDP tribofilm during friction process influences on its mechanical properties.

  5. Spectral non-equilibrium property in homogeneous isotropic turbulence and its implication in subgrid-scale modeling

    The non-equilibrium property in turbulence is a non-negligible problem in large-eddy simulation but has not yet been systematically considered. The generalization from equilibrium turbulence to non-equilibrium turbulence requires a clear recognition of the non-equilibrium property. As a preliminary step of this recognition, the present letter defines a typical non-equilibrium process, that is, the spectral non-equilibrium process, in homogeneous isotropic turbulence. It is then theoretically investigated by employing the skewness of grid-scale velocity gradient, which permits the decomposition of resolved velocity field into an equilibrium one and a time-reversed one. Based on this decomposition, an improved Smagorinsky model is proposed to correct the non-equilibrium behavior of the traditional Smagorinsky model. The present study is expected to shed light on the future studies of more generalized non-equilibrium turbulent flows. - Highlights: • A spectral non-equilibrium process in isotropic turbulence is defined theoretically. • A decomposition method is proposed to divide a non-equilibrium turbulence field. • An improved Smagorinsky model is proposed to correct the non-equilibrium behavior

  6. A Comparison of Three Approaches to the Reduced-Scaling Coupled Cluster Treatment of Non-Resonant Molecular Response Properties.

    McAlexander, Harley R; Crawford, T Daniel

    2016-01-12

    We have investigated the performance of the reduced-scaling coupled cluster method based on projected atomic orbitals (PAOs), pair natural orbitals (PNOs), and orbital specific virtuals (OSVs) for the prediction of linear response properties. These methods introduce different degrees of controllable sparsity in the ground-state and perturbed coupled cluster wave functions, leading to localization errors in properties such as dynamic polarizabilities and specific optical rotations. Using a series of chiral test compounds, we find that the inherent costs associated with computing response properties are significantly greater than those for determining the ground-state energy. As the dimensionality of the molecular system increases-from (pseudo)linear structures, such as fluoroalkanes, to cagelike structures, such as β-pinene-the crossover point between canonical-orbital and localized-orbital algorithms increases substantially. Furthermore, both the OSV and PNO methods provide greater reduction in cost (as measured by the size of the double-excitation space) than do PAOs, and PNOs provide the greatest level of sparsity for the systems examined here. Single-excitation truncation induces much larger errors than corresponding doubles truncation due to the fact that the first-order contribution to the one-electron perturbed wave function appears in the singles amplitudes. Both the PNO and OSV methods perform reasonably well for frequency-dependent polarizabilities provided appropriate thresholds are used for the occupation-number and weak-pair cutoffs on which each method depends. Specific rotations, however, are very sensitive to wave function truncation, to the extent that aggressive thresholds can yield the incorrect sign of the rotation, due to the delicate balance of positive and negative wave function contributions to the mixed electric-/magnetic-field response. PMID:26626230

  7. Scaling properties of the chiral phase transition in the low density region of two-flavor QCD with improved Wilson fermions

    Umeda, T; Kanaya, K; Maezawa, Y; Nakagawa, Y; Ohno, H; Saito, H; Yoshida, S

    2013-01-01

    We study scaling behavior of a chiral order parameter in the low density region, performing a simulation of two-flavor QCD with improved Wilson quarks. The scaling behavior of the chiral order parameter defined by a Ward-Takahashi identity agrees with the scaling function of the three-dimensional O(4) spin model at zero chemical potential. We extend the scaling study to finite density QCD. Applying the reweighting method and calculating derivatives of the chiral order parameter with respect to the chemical potential, the scaling properties of the chiral phase transition are discussed in the low density region. We moreover calculate the curvature of the phase boundary of the chiral phase transition in the temperature and chemical potential plane assuming the O(4) scaling relation.

  8. Hydration of swelling clays: multi-scale sequence of hydration and determination of macroscopic energies from microscopic properties

    Smectites have interesting properties which make them potential candidates for engineered barriers in deep geological nuclear waste repository: low permeability, swelling and cations retention. The subject of this thesis consists in the determination of the relationship between hydration properties, swelling properties and cations mobility in relation with confinement properties of clayey materials. The aim is to understand and to predict the behaviour of water in smectites, following two research orientations: the mechanistic aspects and the energetic aspects of the hydration of smectites. We worked on the Na-Ca montmorillonite contained in the MX80 bentonite, with the exchanged homo ionic structure (saturated with alkaline cations and calcium cations). The approach crosses the various scales (microscopic, mesoscopic and macroscopic) and implied the study of the various components of the system (layer-cation-water), by using original experimental methods (thermo-poro-metry and electric conductivity for various relative humidities (RH) and electrostatic calculations. Initially, the dry state is defined by SCTA (scanning calorimetry thermal analysis). Then a classical characterization of the smectite porosity for the dry state is carried out using mercury intrusion and nitrogen adsorption. We evidenced the existence of a meso-porosity which radius varies from 2 to 10 nm depending on the compensating cation. The thermo-poro-metry and conductivity experiments performed at various hydration states made it possible to follow the increase in the pore sizes and the cations mobility as a function of the hydration state. We highlight in particular the existence of an osmotic mesoscopic swelling for low RH (approximately 50-60%RH for Li and Na). By combining the results of thermo-poro-metry, X-ray diffraction and electric conductivity, we are able to propose a complete hydration sequence for each cation, showing the crucial role of the compensating cation in the hydration of

  9. Challenges in the Application of Fractional Derivative Models in Capturing Solute Transport in Porous Media: Darcy-Scale Fractional Dispersion and the Influence of Medium Properties

    Yong Zhang; Charalambos Papelis; Young, Michael H.; Markus Berli

    2013-01-01

    Heterogeneous media consisting of segregated flow regions are fractional-order systems, where the regional-scale anomalous diffusion can be described by the fractional derivative model (FDM). The standard FDM, however, first, cannot characterize the Darcy-scale dispersion through repacked sand columns, and second, the link between medium properties and model parameters remains unknown. To fill these two knowledge gaps, this study applies a tempered fractional derivative model (TFDM) to captur...

  10. Clinical assessment of bipolar depression: validity, factor structure and psychometric properties of the Korean version of the Bipolar Depression Rating Scale (BDRS)

    Jung, Young-Eun; Kim, Moon-Doo; Bahk, Won-Myong; Woo, Young Sup; Lee, Jonghun; Jang, Sae-Heon; Won, Seunghee; Min, Kyung Joon; Chung, Sangkeun; Kwon, Young-Joon; Jon, Duk-In; Lee, Kwanghun; Yoon, Bo-Hyun

    2016-01-01

    Background The Bipolar Depression Rating Scale (BDRS) is a scale for assessment of the clinical characteristics of bipolar depression. The primary aims of this study were to describe the development of the Korean version of the BDRS (K-BDRS) and to establish more firmly its psychometric properties in terms of reliability and validity. Methods The study included 141 patients (62 male and 79 female) who had been diagnosed with bipolar disorder, were currently experiencing symptoms of depression...

  11. Scaling Properties of Biologically Active Scalar Concentration Fluctuations in the Atmospheric Surface Layer over a Managed Peatland

    Detto, Matteo; Baldocchi, Dennis; Katul, Gabriel G.

    2010-09-01

    The higher-order scalar concentration fluctuation properties are examined in the context of Monin-Obukhov similarity theory for a variety of greenhouse gases that have distinct and separate source/sink locations along an otherwise ideal micrometeorological field site. Air temperature and concentrations of water vapour, carbon dioxide and methane were measured at high frequency (10 Hz) above a flat and extensive peat-land soil in the San Joaquin-Sacramento Delta (California, USA) area, subjected to year-round grazing by beef cattle. Because of the heterogeneous distribution of the sources and sinks of CO2 and especially CH4 emitted by cattle, the scaling behaviour of the higher-order statistical properties diverged from predictions based on a balance between their production and dissipation rate terms, which can obtained for temperature and H2O during stationary conditions. We identify and label these departures as ‘exogenous’ because they depend on heterogeneities and non-stationarities induced by boundary conditions on the flow. Spectral analysis revealed that the exogenous effects show their signatures in regions with frequencies lower than those associated with scalar vertical transport by turbulence, though the two regions may partially overlap in some cases. Cospectra of vertical fluxes appear less influenced by these exogenous effects because of the modulating role of the vertical velocity at low frequencies. Finally, under certain conditions, the presence of such exogenous factors in higher-order scalar fluctuation statistics may be ‘fingerprinted’ by a large storage term in the mean scalar budget.

  12. Structure and Properties of Nano- and Meso-Scale Materials Prepared by Designed Self-Assembly of Nanoparticles

    Lukach, Ariella

    The work presented in this thesis explores the homo- and co-assembly process, structural characteristics and properties of nano- and meso-scale, one- and three-dimensional structures composed of nanoscale building blocks. In chapter 3, we developed a method for terminating the colloidal polymerization process of gold nanorods by post-assembly photocrosslinking of polymer ligands. By functionalizing gold nanorods with a hydrophobic polymer containing pendant double bonds, we were able to compartmentalize a hydrophobic photoinitiator. We could then suppress the association ability of the polymer ligands by covalently crosslinking them using photoirradiation. The averaged aggregation number of the polymers could be predicted from the kinetics of molecular step-growth polymerization. Furthermore, we found that following crosslinking, the inert-rod distance reduced, and the nanorod co-linearity increased, both allowing for better electromagnetic coupling between the nanorods. In chapter 4, we further explored the resemblance between colloidal and molecular polymerization reactions by applying strategies from molecular copolymerization to the co-assembly of gold nanorods with different dimensions into random and block copolymer structures (plasmonic copolymers). The approach was extended to the co-assembly of random copolymers of gold and palladium nanorods. We showed that the formation of random copolymers is achieved regardless of the composition, size, or concentration if both co-monomers are present at the beginning of the copolymerization. Block copolymers were prepared by combining one pre-polymer with the second monomer, or two pre-polymers. A kinetic model validated and further expanded the kinetic theories developed for molecular copolymerization reactions. Chapters 5 and 6 explore a bottom-up method to produce composite materials from spherical nanoparticles with different core-composition, surface-characteristics, and concentrations and cellulose nanocrystals

  13. Large scale characterization of unsaturated soil properties in a semi-arid region combining infiltration, pedotransfer functions and evaporation tests

    Shabou, Marouen; Angulo-Jaramillo, Rafael; Lassabatère, Laurent; Boulet, Gilles; Mougenot, Bernard; Lili Chabaane, Zohra; Zribi, Mehrez

    2016-04-01

    Water resource management is a major issue in semi-arid regions, especially where irrigated agriculture is dominant on soils with highly variable clay content. Indeed, topsoil clay content has a significant importance on infiltration and evaporation processes and therefore in the estimation of the volume of water needed for crops. In this poster we present several methods to estimate wilting point, field capacity volumetric water contents and saturated hydraulic conductivity of the Kairouan plain (680 km2), central Tunisia (North Africa). The first method relies on the Beerkan Estimation of Soil Transfer parameters (BEST) method, which consists in local estimate of unsaturated soil hydraulic properties from a single-ring infiltration test, combined with the use of pedotransfer functions applied to the Kairouan plain different soil types. Results are obtained over six different topsoil texture classes along the Kairouan plain. Saturated hydraulic conductivity is high for coarse textured and some of the fine textured soils due to shrinkage cracking-macropore soil structure. The saturated hydraulic conductivity values are respectively 1.31E-5 m.s-1 and 1.71E-05 m.s-1. The second method is based on evaporation tests on different test plots. It consists of analyzing soil moisture profile changes during the dry down periods to detect the time-to-stress that can be obtained from observation of soil moisture variation, albedo measurements and variation of soil temperature. Results show that the estimated parameters with the evaporation method are close to those obtained by combining the BEST method and pedotransfer functions. The results validate that combining local infiltration tests and pedotransfer functions is a promising tool for the large scale hydraulic characterization of region with strong spatial variability of soils properties.

  14. Psychometric Properties of the Chinese Version of the Fear of Negative Evaluation Scale-Brief (BFNE) and the BFNE-Straightforward for Middle School Students

    Jia Wei; Chunyu Zhang; Yadan Li; Song Xue; Jinfu Zhang

    2015-01-01

    Background The 12-item brief version of the Fear of Negative Evaluation Scale (BFNE) is one of the most widely used instruments to assess fear of negative evaluation. Recent evidence strongly supports the version composed of 8 straightforward items (BFNE-S), which possessesstronger psychometric properties. The purpose of the current study is to examine the psychometric prop-erties of the Chinese versions of the BFNE and BFNE-S for middle school students. Methodology A total of 1009 middle sch...

  15. Continuous, Large-Scale Processing of Seismic Archives for High-Resolution Monitoring of Seismic Activity and Seismogenic Properties

    Waldhauser, F.; Schaff, D. P.

    2012-12-01

    Archives of digital seismic data recorded by seismometer networks around the world have grown tremendously over the last several decades helped by the deployment of seismic stations and their continued operation within the framework of monitoring earthquake activity and verification of the Nuclear Test-Ban Treaty. We show results from our continuing effort in developing efficient waveform cross-correlation and double-difference analysis methods for the large-scale processing of regional and global seismic archives to improve existing earthquake parameter estimates, detect seismic events with magnitudes below current detection thresholds, and improve real-time monitoring procedures. We demonstrate the performance of these algorithms as applied to the 28-year long seismic archive of the Northern California Seismic Network. The tools enable the computation of periodic updates of a high-resolution earthquake catalog of currently over 500,000 earthquakes using simultaneous double-difference inversions, achieving up to three orders of magnitude resolution improvement over existing hypocenter locations. This catalog, together with associated metadata, form the underlying relational database for a real-time double-difference scheme, DDRT, which rapidly computes high-precision correlation times and hypocenter locations of new events with respect to the background archive (http://ddrt.ldeo.columbia.edu). The DDRT system facilitates near-real-time seismicity analysis, including the ability to search at an unprecedented resolution for spatio-temporal changes in seismogenic properties. In areas with continuously recording stations, we show that a detector built around a scaled cross-correlation function can lower the detection threshold by one magnitude unit compared to the STA/LTA based detector employed at the network. This leads to increased event density, which in turn pushes the resolution capability of our location algorithms. On a global scale, we are currently building

  16. Preliminary data concerning the reliability and psychometric properties of the Greek translation of the 20-item Subjective Well-Being Under Neuroleptic Treatment Scale (SWN-20

    Arapidis Konstantinos

    2009-01-01

    Full Text Available Abstract Background The 20-item Subjective Well-Being Under Neuroleptic Treatment Scale (SWN-20 is a self-report scale developed in order to assess the well-being of patients receiving antipsychotic medication independent of the improvement in their psychotic symptoms. The current study reports on the reliability and the psychometric properties of the Greek translation of the SWN-20. Methods A total of 100 inpatients or outpatients with schizophrenia (79 males and 21 females, aged 42.6 ± 11.35 years old from 3 different facilities were assessed with the Positive and Negative Symptoms Scale (PANSS, the Calgary Depression Scale and the Simpson-Angus Scale, and completed the SWN-20. The statistical analysis included the calculation of Pearson product moment correlation coefficient, the Cronbach α and factor analysis with Varimax normalised rotation. Results The SWN-20 had an α value equal to 0.79 and all the items were equal. The factor analysis revealed the presence of seven factors explaining 66% of total variance. The correlation matrix revealed a moderate relationship of the SWN-20 and its factors with the PANSS-Negative (PANSS-N, PANSS-General Psychopathology (PANSS-G, the Simpson-Angus and the Calgary scales, and no relationship to age, education and income class. Discussion The Greek translation of the SWN-20 is reliable, with psychometric properties close to the original scale.

  17. Flow Patterns around Dark Matter Halos: the Link between Halo Dynamical Properties and Large Scale Tidal Field

    Shi, Jingjing; Mo, Houjun

    2015-01-01

    We study how halo intrinsic dynamical properties are linked to their formation processes, and how both are affected by the large scale tidal field in which halo resides. Halo merger trees obtained from cosmological N-body simulations are used to identify infall halos that are about to merge with their hosts. We find that local tidal field can significantly increase the tangential component of the infall velocity but on average do not change the radial component significantly. These results can be used to explain how the internal velocity anisotropy and spin of halos depend on environment. The position vectors and velocities of infall halos are aligned with the principal axes of the local tidal field, and the alignment depends on the strength of the tidal field. Opposite accretion patterns are found in weak and strong tidal fields, in the sense that in a weak field the accretion flow is dominated by radial motion within the local structure, while a large tangential component is present in a strong field. These...

  18. The effect of atomic-scale defects and dopants on phosphorene electronic structure and quantum transport properties.

    Lopez-Bezanilla, Alejandro

    2016-01-20

    By means of a multi-scale first-principles approach, a description of the local electronic structure of 2D and narrow phosphorene sheets with various types of modifications is presented. Firtly, a rational argument based on the geometry of the pristine and modified P network, and supported by the Wannier functions formalism is introduced to describe a hybridization model of the P atomic orbitals. Ab initio calculations show that non-isoelectronic foreign atoms form quasi-bound states at varying energy levels and create different polarization states depending on the number of valence electrons between P and the doping atom. The quantum transport properties of modified phosphorene ribbons are further described with great accuracy. The distortions on the electronic bands induced by the external species lead to strong backscattering effects on the propagating charge carriers. Depending on the energy of the charge carrier and the type of doping, the conduction may range from the diffusive to the localized regime. Interstitial defects at vacant sites lead to homogeneous transport fingerprints across different types of doping atoms. We suggest that the relatively low values of charge mobility reported in experimental measurements may have its origin in the presence of defects.

  19. A weak gravitational lensing recalibration of the scaling relations linking the gas properties of dark halos to their mass

    Wang, Wenting; Mandelbaum, Rachel; Henriques, Bruno; Anderson, Michael E; Han, Jiaxin

    2015-01-01

    We use weak gravitational lensing to measure mean mass profiles around Locally Brightest Galaxies (LBGs). These are selected from the SDSS/DR7 spectroscopic and photometric catalogues to be brighter than any neighbour projected within 1.0 Mpc and differing in redshift by $ 83\\%$) are expected to be the central galaxies of their dark matter halos. Previous stacking analyses have used this LBG sample to measure mean Sunyaev-Zeldovich flux and mean X-ray luminosity as a function of LBG stellar mass. In both cases, a simulation of the formation of the galaxy population was used to estimate effective halo mass for LBGs of given stellar mass, allowing the derivation of scaling relations between the gas properties of halos and their mass. By comparing results from a variety of simulations to our lensing data, we show that this procedure has significant model dependence reflecting: (i) the failure of any given simulation to reproduce observed galaxy abundances exactly; (ii) a dependence on the cosmology underlying th...

  20. Psychometric Properties of the Polish Version of the Social and Emotional Loneliness Scale for Adults (SELSA-S

    Katarzyna Adamczyk

    2014-12-01

    Full Text Available The development and validation of the Polish-language version of the Social and Emotional Loneliness Scale for Adults (SELSA-S; DiTommaso, Brannen, & Best, 2004 is described in this article. The aim of this study was to translate the SELSA-S into Polish and establish its psychometric properties. A total of 417 university students (262 women and 155 men aged 19-25 years completed the Polish adaptation of the SELSA-S (SELSA-SPL, and several other measures. All three subscales of the SELSA-SPL showed good internal consistency. Correlations between these three subscales and indicators of psychological functioning demonstrated similar patterns to those of the SELSA-S. Exploratory and confirmatory factor analyses confirmed that the structure of the SELSA-SPL was consistent with the original version. The results from the present study indicate that the Polish version of the SELSA-S is a reliable and valid multidimensional measure of loneliness.