Study of the Wavelength Dependence in Laser Ablation of Advanced Ceramics and Glass-Ceramic Materials in the Nanosecond Range.

Science.gov (United States)

Sola, Daniel; Peña, Jose I

2013-11-19

In this work, geometrical dimensions and ablation yields as a function of the machining method and reference position were studied when advanced ceramics and glass-ceramic materials were machined with pulsed lasers in the nanosecond range. Two laser systems, emitting at 1064 and 532 nm, were used. It was shown that the features obtained depend on whether the substrate is processed by means of pulse bursts or by grooves. In particular, when the samples were processed by grooves, machined depth, removed volume and ablation yields reached their maximum, placing the sample out of focus. It was shown that these characteristics do not depend on the processing conditions, the wavelength or the optical configuration, and that this is intrinsic behavior of the processing method. Furthermore, the existence of a close relation between material hardness and ablation yields was demonstrated.

Improving Delay-Range-Dependent Stability Condition for Systems with Interval Time-Varying Delay

Directory of Open Access Journals (Sweden)

Wei Qian

2013-01-01

Full Text Available This paper discusses the delay-range-dependent stability for systems with interval time-varying delay. Through defining the new Lyapunov-Krasovskii functional and estimating the derivative of the LKF by introducing new vectors, using free matrices and reciprocally convex approach, the new delay-range-dependent stability conditions are obtained. Two well-known examples are given to illustrate the less conservatism of the proposed theoretical results.

Energy dependence of polymer gels in the orthovoltage energy range

Directory of Open Access Journals (Sweden)

Yvonne Roed

2014-03-01

Full Text Available Purpose: Ortho-voltage energies are often used for treatment of patients’ superficial lesions, and also for small- animal irradiations. Polymer-Gel dosimeters such as MAGAT (Methacrylic acid Gel and THPC are finding increasing use for 3-dimensional verification of radiation doses in a given treatment geometry. For mega-voltage beams, energy dependence of MAGAT has been quoted as nearly energy-independent. In the kilo-voltage range, there is hardly any literature to shade light on its energy dependence.Methods: MAGAT was used to measure depth-dose for 250 kVp beam. Comparison with ion-chamber data showed a discrepancy increasing significantly with depth. An over-response as much as 25% was observed at a depth of 6 cm.Results and Conclusion: Investigation concluded that 6 cm water in the beam resulted in a half-value-layer (HVL change from 1.05 to 1.32 mm Cu. This amounts to an effective-energy change from 81.3 to 89.5 keV. Response measurements of MAGAT at these two energies explained the observed discrepancy in depth-dose measurements. Dose-calibration curves of MAGAT for (i 250 kVp beam, and (ii 250 kVp beam through 6 cm of water column are presented showing significant energy dependence.-------------------Cite this article as: Roed Y, Tailor R, Pinksy L, Ibbott G. Energy dependence of polymer gels in the orthovoltage energy range. Int J Cancer Ther Oncol 2014; 2(2:020232. DOI: 10.14319/ijcto.0202.32 

Stochastic processes and long range dependence

CERN Document Server

Samorodnitsky, Gennady

2016-01-01

This monograph is a gateway for researchers and graduate students to explore the profound, yet subtle, world of long-range dependence (also known as long memory). The text is organized around the probabilistic properties of stationary processes that are important for determining the presence or absence of long memory. The first few chapters serve as an overview of the general theory of stochastic processes which gives the reader sufficient background, language, and models for the subsequent discussion of long memory. The later chapters devoted to long memory begin with an introduction to the subject along with a brief history of its development, followed by a presentation of what is currently the best known approach, applicable to stationary processes with a finite second moment. The book concludes with a chapter devoted to the author’s own, less standard, point of view of long memory as a phase transition, and even includes some novel results. Most of the material in the book has not previously been publis...

Multi-configuration time-dependent density-functional theory based on range separation

DEFF Research Database (Denmark)

Fromager, E.; Knecht, S.; Jensen, Hans Jørgen Aagaard

2013-01-01

Multi-configuration range-separated density-functional theory is extended to the time-dependent regime. An exact variational formulation is derived. The approximation, which consists in combining a long-range Multi-Configuration- Self-Consistent Field (MCSCF) treatment with an adiabatic short...... (srGGA) approximations. As expected, when modeling long-range interactions with the MCSCF model instead of the adiabatic Buijse-Baerends density-matrix functional as recently proposed by Pernal [J. Chem. Phys. 136, 184105 (2012)10.1063/1.4712019], the description of both the 1D doubly-excited state...

Exploring flavor-dependent long-range forces in long-baseline neutrino oscillation experiments

Science.gov (United States)

Chatterjee, Sabya Sachi; Dasgupta, Arnab; Agarwalla, Sanjib Kumar

2015-12-01

The Standard Model gauge group can be extended with minimal matter content by introducing anomaly free U(1) symmetry, such as L e - L μ or L e - L τ . If the neutral gauge boson corresponding to this abelian symmetry is ultra-light, then it will give rise to flavor-dependent long-range leptonic force, which can have significant impact on neutrino oscillations. For an instance, the electrons inside the Sun can generate a flavor-dependent long-range potential at the Earth surface, which can suppress the ν μ → ν e appearance probability in terrestrial experiments. The sign of this potential is opposite for anti-neutrinos, and affects the oscillations of (anti-)neutrinos in different fashion. This feature invokes fake CP-asymmetry like the SM matter effect and can severely affect the leptonic CP-violation searches in long-baseline experiments. In this paper, we study in detail the possible impacts of these long-range flavor-diagonal neutral current interactions due to L e - L μ symmetry, when (anti-)neutrinos travel from Fermilab to Homestake (1300 km) and CERN to Pyhäsalmi (2290 km) in the context of future high-precision superbeam facilities, DUNE and LBNO respectively. If there is no signal of long-range force, DUNE (LBNO) can place stringent constraint on the effective gauge coupling α eμ < 1.9 × 10-53 (7.8 × 10-54) at 90% C.L., which is almost 30 (70) times better than the existing bound from the Super-Kamiokande experiment. We also observe that if α eμ ≥ 2 × 10-52, the CP-violation discovery reach of these future facilities vanishes completely. The mass hierarchy measurement remains robust in DUNE (LBNO) if α eμ < 5 × 10-52 (10-52).

Determination of Age-Dependent Reference Ranges for Coagulation Tests Performed Using Destiny Plus.

Science.gov (United States)

Arslan, Fatma Demet; Serdar, Muhittin; Merve Ari, Elif; Onur Oztan, Mustafa; Hikmet Kozcu, Sureyya; Tarhan, Huseyin; Cakmak, Ozgur; Zeytinli, Merve; Yasar Ellidag, Hamit

2016-06-01

In order to apply the right treatment for hemostatic disorders in pediatric patients, laboratory data should be interpreted with age-appropriate reference ranges. The purpose of this study was to determining age-dependent reference range values for prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen tests, and D-dimer tests. A total of 320 volunteers were included in the study with the following ages: 1 month - 1 year (n = 52), 2 - 5 years (n = 50), 6 - 10 years (n = 48), 11 - 17 years (n = 38), and 18 - 65 years (n = 132). Each volunteer completed a survey to exclude hemostatic system disorder. Using a nonparametric method, the lower and upper limits, including 95% distribution and 90% confidence intervals, were calculated. No statistically significant differences were found between PT and aPTT values in the groups consisting of children. Thus, the reference ranges were separated into child and adult age groups. PT and aPTT values were significantly higher in the children than in the adults. Fibrinogen values in the 6 - 10 age group and the adult age group were significantly higher than in the other groups. D-dimer levels were significantly lower in those aged 2 - 17; thus, a separate reference range was established. These results support other findings related to developmental hemostasis, confirming that adult and pediatric age groups should be evaluated using different reference ranges.

A study of the angular momentum dependence of the phase shift for finite range and Coulomb potentials

International Nuclear Information System (INIS)

Valluri, S.R.; Romo, W.J.

1989-01-01

The dependence of the phase shift δ l (k) on the angular momentum l is investigated. An analytic expression for the derivative of the phase shift with respect to angular momentum is derived for a class of potentials that includes complex and real potentials. The potentials behave like the finite range potential for small r and like a Coulomb potential for large r. Specific examples like the square well, the pure point charge Coulomb and a combination of a square well and the Coulomb potential are analytically treated. Possible applications are briefly indicated. (orig.)

System Estimation of Panel Data Models under Long-Range Dependence

DEFF Research Database (Denmark)

Ergemen, Yunus Emre

A general dynamic panel data model is considered that incorporates individual and interactive fixed effects allowing for contemporaneous correlation in model innovations. The model accommodates general stationary or nonstationary long-range dependence through interactive fixed effects...... and innovations, removing the necessity to perform a priori unit-root or stationarity testing. Moreover, persistence in innovations and interactive fixed effects allows for cointegration; innovations can also have vector-autoregressive dynamics; deterministic trends can be featured. Estimations are performed...

Common long-range dependence in a panel of hourly Nord Pool electricity prices and loads

DEFF Research Database (Denmark)

Ergemen, Yunus Emre; Haldrup, Niels; Rodríguez-Caballero, Carlos Vladimir

to strong seasonal periodicity, and along the cross-sectional dimension, i.e. the hours of the day, there is a strong dependence which necessarily has to be accounted for in order to avoid spurious inference when focusing on the time series dependence alone. The long-range dependence is modelled in terms...... of a fractionally integrated panel data model and it is shown that both prices and loads consist of common factors with long memory and with loadings that vary considerably during the day. Due to the competitiveness of the Nordic power market the aggregate supply curve approximates well the marginal costs...... data approaches to analyse the time series and the cross-sectional dependence of hourly Nord Pool electricity spot prices and loads for the period 2000-2013. Hourly electricity prices and loads data are characterized by strong serial long-range dependence in the time series dimension in addition...

Breakdown of long-range temporal dependence in default mode and attention networks during deep sleep.

Science.gov (United States)

Tagliazucchi, Enzo; von Wegner, Frederic; Morzelewski, Astrid; Brodbeck, Verena; Jahnke, Kolja; Laufs, Helmut

2013-09-17

The integration of segregated brain functional modules is a prerequisite for conscious awareness during wakeful rest. Here, we test the hypothesis that temporal integration, measured as long-term memory in the history of neural activity, is another important quality underlying conscious awareness. For this aim, we study the temporal memory of blood oxygen level-dependent signals across the human nonrapid eye movement sleep cycle. Results reveal that this property gradually decreases from wakefulness to deep nonrapid eye movement sleep and that such decreases affect areas identified with default mode and attention networks. Although blood oxygen level-dependent spontaneous fluctuations exhibit nontrivial spatial organization, even during deep sleep, they also display a decreased temporal complexity in specific brain regions. Conversely, this result suggests that long-range temporal dependence might be an attribute of the spontaneous conscious mentation performed during wakeful rest.

Generalized Efficient Inference on Factor Models with Long-Range Dependence

DEFF Research Database (Denmark)

Ergemen, Yunus Emre

. Short-memory dynamics are allowed in the common factor structure and possibly heteroskedastic error term. In the estimation, a generalized version of the principal components (PC) approach is proposed to achieve efficiency. Asymptotics for efficient common factor and factor loading as well as long......A dynamic factor model is considered that contains stochastic time trends allowing for stationary and nonstationary long-range dependence. The model nests standard I(0) and I(1) behaviour smoothly in common factors and residuals, removing the necessity of a priori unit-root and stationarity testing...

Earthquake simulations with time-dependent nucleation and long-range interactions

Directory of Open Access Journals (Sweden)

J. H. Dieterich

1995-01-01

Full Text Available A model for rapid simulation of earthquake sequences is introduced which incorporates long-range elastic interactions among fault elements and time-dependent earthquake nucleation inferred from experimentally derived rate- and state-dependent fault constitutive properties. The model consists of a planar two-dimensional fault surface which is periodic in both the x- and y-directions. Elastic interactions among fault elements are represented by an array of elastic dislocations. Approximate solutions for earthquake nucleation and dynamics of earthquake slip are introduced which permit computations to proceed in steps that are determined by the transitions from one sliding state to the next. The transition-driven time stepping and avoidance of systems of simultaneous equations permit rapid simulation of large sequences of earthquake events on computers of modest capacity, while preserving characteristics of the nucleation and rupture propagation processes evident in more detailed models. Earthquakes simulated with this model reproduce many of the observed spatial and temporal characteristics of clustering phenomena including foreshock and aftershock sequences. Clustering arises because the time dependence of the nucleation process is highly sensitive to stress perturbations caused by nearby earthquakes. Rate of earthquake activity following a prior earthquake decays according to Omori's aftershock decay law and falls off with distance.

Short-range correlations in an extended time-dependent mean-field theory

International Nuclear Information System (INIS)

Madler, P.

1982-01-01

A generalization is performed of the time-dependent mean-field theory by an explicit inclusion of strong short-range correlations on a level of microscopic reversibility relating them to realistic nucleon-nucleon forces. Invoking a least action principle for correlated trial wave functions, equations of motion for the correlation functions and the single-particle model wave function are derived in lowest order of the FAHT cluster expansion. Higher order effects as well as long-range correlations are consider only to the extent to which they contribute to the mean field via a readjusted phenomenological effective two-body interaction. The corresponding correlated stationary problem is investigated and appropriate initial conditions to describe a heavy ion reaction are proposed. The singleparticle density matrix is evaluated

Range dependent characteristics in the head-related transfer functions of a bat-head cast: part 2. Binaural characteristics

International Nuclear Information System (INIS)

Kim, S; Allen, R; Rowan, D

2012-01-01

Further innovations in bio-inspired engineering based on biosonar systems, such as bats, may arise from more detailed understanding of the underlying acoustic processes. This includes the range-dependent properties of bat heads and ears, particularly at the higher frequencies of bat vocalizations. In a companion paper Kim et al (2012 Bioinspir. Biomim.), range-dependent head-related transfer functions of a bat head cast were investigated up to 100 kHz at either ear (i.e. monaural features). The current paper extends this to consider range-dependent spectral and temporal disparities between the two ears (i.e. binaural features), using experimental data and a spherical model of a bat head to provide insights into the physical basis for these features. It was found that binaural temporal and high-frequency binaural spectral features are approximately independent of distance, having the effect of decreasing their angular resolution at close range. In contrast, low-frequency binaural spectral features are strongly distance-dependent, such that angular sensitivity can be maintained by lowering the frequency of the echolocation emission at close range. Together with the companion paper Kim et al, we speculate that distance-dependent low-frequency monaural and binaural features at short range might help explain why some species of bats that drop the frequency of their calls on target approach while approaching a target. This also provides an impetus for the design of effective emissions in sonar engineering applied to similar tasks. (paper)

Long Range Dependence Prognostics for Bearing Vibration Intensity Chaotic Time Series

Directory of Open Access Journals (Sweden)

Qing Li

2016-01-01

Full Text Available According to the chaotic features and typical fractional order characteristics of the bearing vibration intensity time series, a forecasting approach based on long range dependence (LRD is proposed. In order to reveal the internal chaotic properties, vibration intensity time series are reconstructed based on chaos theory in phase-space, the delay time is computed with C-C method and the optimal embedding dimension and saturated correlation dimension are calculated via the Grassberger–Procaccia (G-P method, respectively, so that the chaotic characteristics of vibration intensity time series can be jointly determined by the largest Lyapunov exponent and phase plane trajectory of vibration intensity time series, meanwhile, the largest Lyapunov exponent is calculated by the Wolf method and phase plane trajectory is illustrated using Duffing-Holmes Oscillator (DHO. The Hurst exponent and long range dependence prediction method are proposed to verify the typical fractional order features and improve the prediction accuracy of bearing vibration intensity time series, respectively. Experience shows that the vibration intensity time series have chaotic properties and the LRD prediction method is better than the other prediction methods (largest Lyapunov, auto regressive moving average (ARMA and BP neural network (BPNN model in prediction accuracy and prediction performance, which provides a new approach for running tendency predictions for rotating machinery and provide some guidance value to the engineering practice.

NEUTRON-PROTON EFFECTIVE RANGE PARAMETERS AND ZERO-ENERGY SHAPE DEPENDENCE.

Energy Technology Data Exchange (ETDEWEB)

HACKENBURG, R.W.

2005-06-01

A completely model-independent effective range theory fit to available, unpolarized, np scattering data below 3 MeV determines the zero-energy free proton cross section {sigma}{sub 0} = 20.4287 {+-} 0.0078 b, the singlet apparent effective range r{sub s} = 2.754 {+-} 0.018{sub stat} {+-} 0.056{sub syst} fm, and improves the error slightly on the parahydrogen coherent scattering length, a{sub c} = -3.7406 {+-} 0.0010 fm. The triplet and singlet scattering lengths and the triplet mixed effective range are calculated to be a{sub t} = 5.4114 {+-} 0.0015 fm, a{sub s} = -23.7153 {+-} 0.0043 fm, and {rho}{sub t}(0,-{epsilon}{sub t}) = 1.7468 {+-} 0.0019 fm. The model-independent analysis also determines the zero-energy effective ranges by treating them as separate fit parameters without the constraint from the deuteron binding energy {epsilon}{sub t}. These are determined to be {rho}{sub t}(0,0) = 1.705 {+-} 0.023 fm and {rho}{sub s}(0,0) = 2.665 {+-} 0.056 fm. This determination of {rho}{sub t}(0,0) and {rho}{sub s}(0,0) is most sensitive to the sparse data between about 20 and 600 keV, where the correlation between the determined values of {rho}{sub t}(0,0) and {rho}{sub s}(0,0) is at a minimum. This correlation is responsible for the large systematic error in r{sub s}. More precise data in this range are needed. The present data do not event determine (with confidence) that {rho}{sub t}(0,0) {ne} {rho}{sub t}(0, -{epsilon}{sub t}), referred to here as ''zero-energy shape dependence''. The widely used measurement of {sigma}{sub 0} = 20.491 {+-} 0.014 b from W. Dilg, Phys. Rev. C 11, 103 (1975), is argued to be in error.

Studies of time dependence of fields in TEVATRON superconducting dipole magnets

International Nuclear Information System (INIS)

Hanft, R.W.; Brown, B.C.; Herrup, D.A.; Lamm, M.J.; McInturff, A.D.; Syphers, M.J.

1988-01-01

The time variation in the magnetic field of a model Tevatron dipole magnet at constant excitation current has been studied. Variations in symmetry allowed harmonic components over long time ranges show a log t behavior indicative of ''flux creep.'' Both short time range and long time range behavior depend in a detailed way on the excitation history. Similar effects are seen in the remnant fields present in full-scale Tevatron dipoles following current ramping. Both magnitudes and time dependences are observed to depend on details for the ramps, such as ramp rate, flattop duration, and number of ramps. In a few magnets, variations are also seen in symmetry unallowed harmonics. 9 refs., 10 figs

Long-range spatial dependence in fractured rock. Empirical evidence and implications for tracer transport

International Nuclear Information System (INIS)

Painter, S.

1999-02-01

Nonclassical stochastic continuum models incorporating long-range spatial dependence are evaluated as models for fractured crystalline rock. Open fractures and fracture zones are not modeled explicitly in this approach. The fracture zones and intact rock are modeled as a single stochastic continuum. The large contrasts between the fracture zones and unfractured rock are accounted for by making use of random field models specifically designed for highly variable systems. Hydraulic conductivity data derived from packer tests in the vicinity of the Aespoe Hard Rock Laboratory form the basis for the evaluation. The Aespoe log K data were found to be consistent with a fractal scaling model based on bounded fractional Levy motion (bfLm), a model that has been used previously to model highly variable sedimentary formations. However, the data are not sufficient to choose between this model, a fractional Brownian motion model for the normal-score transform of log K, and a conventional geostatistical model. Stochastic simulations conditioned by the Aespoe data coupled with flow and tracer transport calculations demonstrate that the models with long-range dependence predict earlier arrival times for contaminants. This demonstrates the need to evaluate this class of models when assessing the performance of proposed waste repositories. The relationship between intermediate-scale and large-scale transport properties in media with long-range dependence is also addressed. A new Monte Carlo method for stochastic upscaling of intermediate-scale field data is proposed

Temperature dependence of muonium spin exchange with O2 in the range 88 K to 478 K

International Nuclear Information System (INIS)

Senba, M.; Garner, D.M.; Arseneau, D.J.; Fleming, D.G.

1984-01-01

The authors have extended an earlier study of the spin exchange reactions of Mu with O 2 in the range 295 K to 478 K, to a low temperature region down to 88 K. From 135 K to 296 K, the spin depolarization rate constant was found to vary according to the relative velocity of the colliding species, which indicates that the spin exchange cross section of Mu-O 2 is temperature independent in this range. However, it was found that below 105 K and above 400 K, the spin depolarization rate constant tends to have stronger temperature dependences. (Auth.)

Study of Cu-Al-Zn alloys hardness temperature dependence

International Nuclear Information System (INIS)

Kurmanova, D.T.; Skakov, M.K.; Melikhov, V.D.

2001-01-01

In the paper the results of studies for the Cu-Al-Zn ternary alloys hardness temperature dependence are presented. The method of 'hot hardness' has been used during study of the solid state phase transformations and under determination of the hot stability boundaries. Due to the samples brittleness a hardness temperature dependence definition is possible only from 350-400 deg. C. Sensitivity of the 'hot hardness' method is decreasing within high plasticity range, so the measurements have been carried out only up to 700-800 deg. C. It is shown, that the alloys hardness dependence character from temperature is close to exponential one within the certain structure modification existence domain

Electron transport in furfural: dependence of the electron ranges on the cross sections and the energy loss distribution functions

Science.gov (United States)

Ellis-Gibbings, L.; Krupa, K.; Colmenares, R.; Blanco, F.; Muńoz, A.; Mendes, M.; Ferreira da Silva, F.; Limá Vieira, P.; Jones, D. B.; Brunger, M. J.; García, G.

2016-09-01

Recent theoretical and experimental studies have provided a complete set of differential and integral electron scattering cross section data from furfural over a broad energy range. The energy loss distribution functions have been determined in this study by averaging electron energy loss spectra for different incident energies and scattering angles. All these data have been used as input parameters for an event by event Monte Carlo simulation procedure to obtain the electron energy deposition patterns and electron ranges in liquid furfural. The dependence of these results on the input cross sections is then analysed to determine the uncertainty of the simulated values.

Landau parameters for finite range density dependent nuclear interactions

International Nuclear Information System (INIS)

Farine, M.

1997-01-01

The Landau parameters represent the effective particle-hole interaction at Fermi level. Since between the physical observables and the Landau parameters there is a direct relation their derivation from an effective interaction is of great interest. The parameter F 0 determines the incompressibility K of the system. The parameter F 1 determines the effective mass (which controls the level density at the Fermi level). In addition, F 0 ' determines the symmetry energy, G 0 the magnetic susceptibility, and G 0 ' the pion condensation threshold in nuclear matter. This paper is devoted to a general derivation of Landau parameters for an interaction with density dependent finite range terms. Particular carefulness is devoted to the inclusion of rearrangement terms. This report is part of a larger project which aims at defining a new nuclear interaction improving the well-known D1 force of Gogny et al. for describing the average nuclear properties and exotic nuclei and satisfying, in addition, the sum rules

Scattering from extended targets in range-dependent fluctuating ocean-waveguides with clutter from theory and experiments.

Science.gov (United States)

Jagannathan, Srinivasan; Küsel, Elizabeth T; Ratilal, Purnima; Makris, Nicholas C

2012-08-01

Bistatic, long-range measurements of acoustic scattered returns from vertically extended, air-filled tubular targets were made during three distinct field experiments in fluctuating continental shelf waveguides. It is shown that Sonar Equation estimates of mean target-scattered intensity lead to large errors, differing by an order of magnitude from both the measurements and waveguide scattering theory. The use of the Ingenito scattering model is also shown to lead to significant errors in estimating mean target-scattered intensity in the field experiments because they were conducted in range-dependent ocean environments with large variations in sound speed structure over the depth of the targets, scenarios that violate basic assumptions of the Ingenito model. Green's theorem based full-field modeling that describes scattering from vertically extended tubular targets in range-dependent ocean waveguides by taking into account nonuniform sound speed structure over the target's depth extent is shown to accurately describe the statistics of the targets' scattered field in all three field experiments. Returns from the man-made targets are also shown to have a very different spectral dependence from the natural target-like clutter of the dominant fish schools observed, suggesting that judicious multi-frequency sensing may often provide a useful means of distinguishing fish from man-made targets.

Fluctuations and pseudo long range dependence in network flows: A non-stationary Poisson process model

International Nuclear Information System (INIS)

Yu-Dong, Chen; Li, Li; Yi, Zhang; Jian-Ming, Hu

2009-01-01

In the study of complex networks (systems), the scaling phenomenon of flow fluctuations refers to a certain power-law between the mean flux (activity) (F i ) of the i-th node and its variance σ i as σ i α (F i ) α . Such scaling laws are found to be prevalent both in natural and man-made network systems, but the understanding of their origins still remains limited. This paper proposes a non-stationary Poisson process model to give an analytical explanation of the non-universal scaling phenomenon: the exponent α varies between 1/2 and 1 depending on the size of sampling time window and the relative strength of the external/internal driven forces of the systems. The crossover behaviour and the relation of fluctuation scaling with pseudo long range dependence are also accounted for by the model. Numerical experiments show that the proposed model can recover the multi-scaling phenomenon. (general)

The temperature dependence of the BK channel activity - kinetics, thermodynamics, and long-range correlations.

Science.gov (United States)

Wawrzkiewicz-Jałowiecka, Agata; Dworakowska, Beata; Grzywna, Zbigniew J

2017-10-01

Large-conductance, voltage dependent, Ca 2+ -activated potassium channels (BK) are transmembrane proteins that regulate many biological processes by controlling potassium flow across cell membranes. Here, we investigate to what extent temperature (in the range of 17-37°C with ΔT=5°C step) is a regulating parameter of kinetic properties of the channel gating and memory effect in the series of dwell-time series of subsequent channel's states, at membrane depolarization and hyperpolarization. The obtained results indicate that temperature affects strongly the BK channels' gating, but, counterintuitively, it exerts no effect on the long-range correlations, as measured by the Hurst coefficient. Quantitative differences between dependencies of appropriate channel's characteristics on temperature are evident for different regimes of voltage. Examining the characteristics of BK channel activity as a function of temperature allows to estimate the net activation energy (E act ) and changes of thermodynamic parameters (ΔH, ΔS, ΔG) by channel opening. Larger E act corresponds to the channel activity at membrane hyperpolarization. The analysis of entropy and enthalpy changes of closed to open channel's transition suggest the entropy-driven nature of the increase of open state probability during voltage activation and supports the hypothesis about the voltage-dependent geometry of the channel vestibule. Copyright © 2017 Elsevier B.V. All rights reserved.

Searching for long-range dependence in real effective exchange rate: towards parity?

Directory of Open Access Journals (Sweden)

André M. Marques

2015-12-01

Full Text Available Abstract After the widespread adoption of flexible exchange rate regime since 1973 the volatility of the exchange rate has increased, as a consequence of greater trade openness and financial integration. As a result, it has become difficult to find evidence of the purchasing power parity hypothesis (PPP. This study investigates the possibility of a fall in the persistence of the real exchange rate as a consequence of the financial and commercial integration by employing monthly real effective exchange rate dataset provided by the International Monetary Fund (IMF. Beginning with an exploratory data analysis in the frequency domain, the fractional coefficient d was estimated employing the bias-reduced estimator on a sample of 20 countries over the period ranging from 1975 to 2011. As the main novelty, this study applies a bias-reduced log-periodogram regression estimator instead of the traditional method proposed by GPH which eliminates the first and higher orders biases by a data-dependent plug-in method for selecting the number of frequencies to minimize asymptotic mean-squared error (MSE. Additionally, this study also estimates a moving window of fifteen years to observe the path of the fractional coefficient in each country. No evidence was found of a statistically significant change in the persistence of the real exchange rate.

Context-dependent JPEG backward-compatible high-dynamic range image compression

Science.gov (United States)

Korshunov, Pavel; Ebrahimi, Touradj

2013-10-01

High-dynamic range (HDR) imaging is expected, together with ultrahigh definition and high-frame rate video, to become a technology that may change photo, TV, and film industries. Many cameras and displays capable of capturing and rendering both HDR images and video are already available in the market. The popularity and full-public adoption of HDR content is, however, hindered by the lack of standards in evaluation of quality, file formats, and compression, as well as large legacy base of low-dynamic range (LDR) displays that are unable to render HDR. To facilitate the wide spread of HDR usage, the backward compatibility of HDR with commonly used legacy technologies for storage, rendering, and compression of video and images are necessary. Although many tone-mapping algorithms are developed for generating viewable LDR content from HDR, there is no consensus of which algorithm to use and under which conditions. We, via a series of subjective evaluations, demonstrate the dependency of the perceptual quality of the tone-mapped LDR images on the context: environmental factors, display parameters, and image content itself. Based on the results of subjective tests, it proposes to extend JPEG file format, the most popular image format, in a backward compatible manner to deal with HDR images also. An architecture to achieve such backward compatibility with JPEG is proposed. A simple implementation of lossy compression demonstrates the efficiency of the proposed architecture compared with the state-of-the-art HDR image compression.

Study of titanium nitride elasticity characteristics in the homogeneity range by ultrasonic resonance method

International Nuclear Information System (INIS)

Khidirov, I.; Khajdarov, T.

1995-01-01

Elasticity characteristics of cubic and tetragonal phases of titanium nitride in the homogeneity range were studied for the first time by ultrasonic resonance method. It is established that the Young modulus, the shift and volume module of cubic titanium nitride elasticity in the homogeneity range change nonlinearly with decrease in nitrogen concentration and correlate with concentration dependences of other physical properties.15 refs., 2 figs

The temperature dependence of intermediate range oxygen-oxygen correlations in liquid water

International Nuclear Information System (INIS)

Schlesinger, Daniel; Pettersson, Lars G. M.; Wikfeldt, K. Thor; Skinner, Lawrie B.; Benmore, Chris J.; Nilsson, Anders

2016-01-01

We analyze the recent temperature dependent oxygen-oxygen pair-distribution functions from experimental high-precision x-ray diffraction data of bulk water by Skinner et al. [J. Chem. Phys. 141, 214507 (2014)] with particular focus on the intermediate range where small, but significant, correlations are found out to 17 Å. The second peak in the pair-distribution function at 4.5 Å is connected to tetrahedral coordination and was shown by Skinner et al. to change behavior with temperature below the temperature of minimum isothermal compressibility. Here we show that this is associated also with a peak growing at 11 Å which strongly indicates a collective character of fluctuations leading to the enhanced compressibility at lower temperatures. We note that the peak at ∼13.2 Å exhibits a temperature dependence similar to that of the density with a maximum close to 277 K or 4 °C. We analyze simulations of the TIP4P/2005 water model in the same manner and find excellent agreement between simulations and experiment albeit with a temperature shift of ∼20 K.

The temperature dependence of intermediate range oxygen-oxygen correlations in liquid water

Energy Technology Data Exchange (ETDEWEB)

Schlesinger, Daniel; Pettersson, Lars G. M., E-mail: Lars.Pettersson@fysik.su.se [Department of Physics, AlbaNova University Center, Stockholm University, SE-106 91 Stockholm (Sweden); Wikfeldt, K. Thor [Department of Physics, AlbaNova University Center, Stockholm University, SE-106 91 Stockholm (Sweden); Science Institute, University of Iceland, VR-III, 107 Reykjavik (Iceland); Skinner, Lawrie B.; Benmore, Chris J. [X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Nilsson, Anders [Department of Physics, AlbaNova University Center, Stockholm University, SE-106 91 Stockholm (Sweden); Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States)

2016-08-28

We analyze the recent temperature dependent oxygen-oxygen pair-distribution functions from experimental high-precision x-ray diffraction data of bulk water by Skinner et al. [J. Chem. Phys. 141, 214507 (2014)] with particular focus on the intermediate range where small, but significant, correlations are found out to 17 Å. The second peak in the pair-distribution function at 4.5 Å is connected to tetrahedral coordination and was shown by Skinner et al. to change behavior with temperature below the temperature of minimum isothermal compressibility. Here we show that this is associated also with a peak growing at 11 Å which strongly indicates a collective character of fluctuations leading to the enhanced compressibility at lower temperatures. We note that the peak at ∼13.2 Å exhibits a temperature dependence similar to that of the density with a maximum close to 277 K or 4 °C. We analyze simulations of the TIP4P/2005 water model in the same manner and find excellent agreement between simulations and experiment albeit with a temperature shift of ∼20 K.

Long-range correlations of different EEG derivations in rats: sleep stage-dependent generators may play a key role

International Nuclear Information System (INIS)

Fang, Guangzhan; Xia, Yang; Lai, Yongxiu; You, Zili; Yao, Dezhong

2010-01-01

For the electroencephalogram (EEG), topographic differences in the long-range temporal correlations would imply that these signals might be affected by specific mechanisms related to the generation of a given neuronal process. So the properties of the generators of various EEG oscillations might be investigated by their spatial differences of the long-range temporal correlations. In the present study, these correlations were characterized with respect to their topography during different vigilance states by detrended fluctuation analysis (DFA). The results indicated that (1) most of the scaling exponents acquired from different EEG derivations for various oscillations were significantly different in each vigilance state; these differences might be resulted from the different quantities and different locations of sleep stage-dependent generators of various neuronal processes; (2) there might be multiple generators of delta and theta over the brain and many of them were sleep stage-dependent; (3) the best site of the frontal electrode in a fronto-parietal bipolar electrode for sleep staging might be above the anterior midline cortex. We suggest that DFA analysis can be used to explore the properties of the generators of a given neuronal oscillation, and the localizations of these generators if more electrodes are involved

Motivation and exercise dependence: a study based on self-determination theory.

Science.gov (United States)

González-Cutre, David; Sicilia, Alvaro

2012-06-01

The objective of this study was to use self-determination theory to analyze the relationships of several motivational variables with exercise dependence. The study involved 531 exercisers, ranging in age from 16 to 60 years old, who responded to differentquestionnaires assessing perception of motivational climate, satisfaction of basic psychological needs, motivation types, and exercise dependence. The results of multiple mediation analysis revealed that ego-involving climate and perceived competence positively predicted exercise dependence in a directed and mediated manner through introjected and external regulation. Gender and age did not moderate the analyzed relationships. These results allow us to better understand the motivational process explaining exercise dependence, demonstrating the negative influence of the ego-involving climate in the context of exercise.

Motivation and Exercise Dependence: A Study Based on Self-Determination Theory

Science.gov (United States)

Gonzalez-Cutre, David; Sicilia, Alvaro

2012-01-01

The objective of this study was to use self-determination theory to analyze the relationships of several motivational variables with exercise dependence. The study involved 531 exercisers, ranging in age from 16 to 60 years old, who responded to different questionnaires assessing perception of motivational climate, satisfaction of basic…

Measurement of angularly dependent spectra of betatron gamma-rays from a laser plasma accelerator with quadrant-sectored range filters

Energy Technology Data Exchange (ETDEWEB)

Jeon, Jong Ho, E-mail: jhjeon07@ibs.re.kr; Nakajima, Kazuhisa, E-mail: naka115@dia-net.ne.jp; Rhee, Yong Joo; Pathak, Vishwa Bandhu; Cho, Myung Hoon; Shin, Jung Hun; Yoo, Byung Ju; Jo, Sung Ha; Shin, Kang Woo [Center for Relativistic Laser Science, Institute for Basic Science (IBS), Gwangju 61005 (Korea, Republic of); Kim, Hyung Taek; Sung, Jae Hee; Lee, Seong Ku; Choi, Il Woo [Center for Relativistic Laser Science, Institute for Basic Science (IBS), Gwangju 61005 (Korea, Republic of); Advanced Photonics Research Institute, GIST, Gwangju 61005 (Korea, Republic of); Hojbota, Calin; Bae, Lee Jin; Jung, Jaehyung; Cho, Min Sang; Cho, Byoung Ick; Nam, Chang Hee [Center for Relativistic Laser Science, Institute for Basic Science (IBS), Gwangju 61005 (Korea, Republic of); Department of Physics and Photon Science, GIST, Gwangju 61005 (Korea, Republic of)

2016-07-15

Measurement of angularly dependent spectra of betatron gamma-rays radiated by GeV electron beams from laser wakefield accelerators (LWFAs) are presented. The angle-resolved spectrum of betatron radiation was deconvolved from the position dependent data measured for a single laser shot with a broadband gamma-ray spectrometer comprising four-quadrant sectored range filters and an unfolding algorithm, based on the Monte Carlo code GEANT4. The unfolded gamma-ray spectra in the photon energy range of 0.1–10 MeV revealed an approximately isotropic angular dependence of the peak photon energy and photon energy-integrated fluence. As expected by the analysis of betatron radiation from LWFAs, the results indicate that unpolarized gamma-rays are emitted by electrons undergoing betatron motion in isotropically distributed orbit planes.

Communication: Orbital instabilities and triplet states from time-dependent density functional theory and long-range corrected functionals

Science.gov (United States)

Sears, John S.; Koerzdoerfer, Thomas; Zhang, Cai-Rong; Brédas, Jean-Luc

2011-10-01

Long-range corrected hybrids represent an increasingly popular class of functionals for density functional theory (DFT) that have proven to be very successful for a wide range of chemical applications. In this Communication, we examine the performance of these functionals for time-dependent (TD)DFT descriptions of triplet excited states. Our results reveal that the triplet energies are particularly sensitive to the range-separation parameter; this sensitivity can be traced back to triplet instabilities in the ground state coming from the large effective amounts of Hartree-Fock exchange included in these functionals. As such, the use of standard long-range corrected functionals for the description of triplet states at the TDDFT level is not recommended.

Range dependent characteristics in the head-related transfer functions of a bat-head cast: part 1. Monaural characteristics

International Nuclear Information System (INIS)

Kim, S; Allen, R; Rowan, D

2012-01-01

Knowledge of biological sonar systems has revolutionized many aspects of sonar engineering and further advances will benefit from more detailed understanding of their underlying acoustical processes. The anatomically diverse, complex and dynamic heads and ears of bats are known to be important for echolocation although their range-dependent properties are not well understood, particularly across the wide frequency range of some bats' vocalizations. The aim of this and a companion paper Kim et al (2012 Bioinspir. Biomim.) is to investigate bat-head acoustics as a function of bat-target distance, based on measurements up to 100 kHz and more robust examination of hardware characteristics in measurements than previously reported, using a cast of a bat head. In this first paper, we consider the spectral features at either ear (i.e. monaural head-related transfer functions). The results show, for example, that there is both higher magnitude and a stronger effect of distance at close range at relatively low frequencies. This might explain, at least in part, why bats adopt a strategy of changing the frequency range of their vocalizations while approaching a target. There is also potential advantage in the design of bio-inspired receivers of using range-dependent HRTFs and utilizing their distinguished frequency characteristics over the distance. (paper)

Memory effects, two color percolation, and the temperature dependence of Mott variable-range hopping

Science.gov (United States)

Agam, Oded; Aleiner, Igor L.

2014-06-01

There are three basic processes that determine hopping transport: (a) hopping between normally empty sites (i.e., having exponentially small occupation numbers at equilibrium), (b) hopping between normally occupied sites, and (c) transitions between normally occupied and unoccupied sites. In conventional theories all these processes are considered Markovian and the correlations of occupation numbers of different sites are believed to be small (i.e., not exponential in temperature). We show that, contrary to this belief, memory effects suppress the processes of type (c) and manifest themselves in a subleading exponential temperature dependence of the variable-range hopping conductivity. This temperature dependence originates from the property that sites of type (a) and (b) form two independent resistor networks that are weakly coupled to each other by processes of type (c). This leads to a two-color percolation problem which we solve in the critical region.

A-dependence study of inclusive phi production

International Nuclear Information System (INIS)

Daum, C.; Rijk, G. de; Dijkstra, H.; Hardwick, C.; Hoogland, W.; Tiecke, H.; Wiggers, L.; Boehringer, T.; Bosman, M.; Chabaud, V.; Hyams, B.; Koetz, U.; Weilhammer, P.; Rozanska, M.; Rybicki, K.; Turala, M.; Belau, E.; Hajduk, Z.; Klanner, R.; Luetjens, G.; Lutz, G.; Maenner, W.; Neugebauer, E.; Seebrunner, H.; Stierlin, U.; Waltermann, G.; Wylie, A.; Zeludziewicz, T.; Bailey, R.; Damerell, C.; Gill, S.; Gillman, A.; Watts, S.; Wickens, F.

1983-10-01

The mass-number dependence of the inclusive phi-meson cross section is measured using two target materials, beryllium and tantalum, in the kinematic range 0 2 . Parametrizing the cross section with sigma(A) + and p-beams respectively. (Auth.)

The watercolor effect: quantitative evidence for luminance-dependent mechanisms of long-range color assimilation.

Science.gov (United States)

Devinck, Frédéric; Delahunt, Peter B; Hardy, Joseph L; Spillmann, Lothar; Werner, John S

2005-05-01

When a dark chromatic contour delineating a figure is flanked on the inside by a brighter chromatic contour, the brighter color will spread into the entire enclosed area. This is known as the watercolor effect (WCE). Here we quantified the effect of color spreading using both color-matching and hue-cancellation tasks. Over a wide range of stimulus chromaticities, there was a reliable shift in color appearance that closely followed the direction of the inducing contour. When the contours were equated in luminance, the WCE was still present, but weak. The magnitude of the color spreading increased with increases in luminance contrast between the two contours. Additionally, as the luminance contrast between the contours increased, the chromaticity of the induced color more closely resembled that of the inside contour. The results support the hypothesis that the WCE is mediated by luminance-dependent mechanisms of long-range color assimilation.

Delay-Range-Dependent H∞ Control for Automatic Mooring Positioning System with Time-Varying Input Delay

Directory of Open Access Journals (Sweden)

Xiaoyu Su

2014-01-01

Full Text Available Aiming at the economy and security of the positioning system in semi-submersible platform, the paper presents a new scheme based on the mooring line switching strategy. Considering the input delay in switching process, H∞ control with time-varying input delay is designed to calculate the control forces to resist disturbing forces. In order to reduce the conservativeness, the information of the lower bound of delay is taken into account, and a Lyapunov function which contains the range of delay is constructed. Besides, the input constraint is considered to avoid breakage of mooring lines. The sufficient conditions for delay-range-dependent stabilization are derived in terms of LMI, and the controller is also obtained. The effectiveness of the proposed approach is illustrated by a realistic design example.

Withdrawal of corticosteroids in inflammatory bowel disease patients after dependency periods ranging from 2 to 45 years: a proposed method.

LENUS (Irish Health Repository)

Murphy, S J

2012-02-01

BACKGROUND: Even in the biologic era, corticosteroid dependency in IBD patients is common and causes a lot of morbidity, but methods of withdrawal are not well described. AIM: To assess the effectiveness of a corticosteroid withdrawal method. METHODS: Twelve patients (10 men, 2 women; 6 ulcerative colitis, 6 Crohn\\'s disease), median age 53.5 years (range 29-75) were included. IBD patients with quiescent disease refractory to conventional weaning were transitioned to oral dexamethasone, educated about symptoms of the corticosteroid withdrawal syndrome (CWS) and weaned under the supervision of an endocrinologist. When patients failed to wean despite a slow weaning pace and their IBD remaining quiescent, low dose synthetic ACTH stimulation testing was performed to assess for adrenal insufficiency. Multivariate analysis was performed to assess predictors of a slow wean. RESULTS: Median durations for disease and corticosteroid dependency were 21 (range 3-45) and 14 (range 2-45) years respectively. Ten patients (83%) were successfully weaned after a median follow-up from final wean of 38 months (range 5-73). Disease flares occurred in two patients, CWS in five and ACTH testing was performed in 10. Multivariate analysis showed that longer duration of corticosteroid use appeared to be associated with a slower wean (P = 0.056). CONCLUSIONS: Corticosteroid withdrawal using this protocol had a high success rate and durable effect and was effective in patients with long-standing (up to 45 years) dependency. As symptoms of CWS mimic symptoms of IBD disease flares, gastroenterologists may have difficulty distinguishing them, which may be a contributory factor to the frequency of corticosteroid dependency in IBD patients.

Experimental study of energy dependence of proton induced fission cross sections for heavy nuclei in the energy range 200-1000 MeV

Energy Technology Data Exchange (ETDEWEB)

Kotov, A.A.; Gavrikov, Yu.A.; Vaishnene, L.A.; Vovchenko, V.G.; Poliakov, V.V.; Fedorov, O.Ya.; Chestnov, Yu.A.; Shchetkovskiy, A.I [Petersburg Nuclear Physics Institute, Gatchina, Leningrad district, Orlova roscha 1, 188300 (Russian Federation); Fukahori, T. [Japan Atomic Energy Research Institute, Tokai-mura, Ibaraki 319-1195 (Japan)

2005-07-01

The results of the total fission cross sections measurements for {sup nat}Pb, {sup 209}Bi, {sup 232}Th, {sup 233}U, {sup 235}U, {sup 238}U, {sup 237}Np and {sup 239}Pu nuclei at the energy proton range 200-1000 MeV are presented. Experiments were carried out at 1 GeV synchrocyclotron of Petersburg Nuclear Physics Institute (Gatchina). The measurement method is based on the registration in coincidence of both complementary fission fragments by two gas parallel plate avalanche counters, located at a short distance and opposite sides of investigated target. The insensitivity of parallel plate avalanche counters to neutron and light charged particles allowed us to place the counters together with target immediately in the proton beam providing a large solid angle acceptance for fission fragment registration and reliable identification of fission events. The proton flux on the target to be studied was determined by direct counting of protons by scintillation telescope. The measured energy dependence of the total fission cross sections is presented. Obtained results are compared with other experimental data as well as with calculation in the frame of the cascade evaporation model. (authors)

Delay-range-dependent exponential H∞ synchronization of a class of delayed neural networks

International Nuclear Information System (INIS)

Karimi, Hamid Reza; Maass, Peter

2009-01-01

This article aims to present a multiple delayed state-feedback control design for exponential H ∞ synchronization problem of a class of delayed neural networks with multiple time-varying discrete delays. On the basis of the drive-response concept and by introducing a descriptor technique and using Lyapunov-Krasovskii functional, new delay-range-dependent sufficient conditions for exponential H ∞ synchronization of the drive-response structure of neural networks are driven in terms of linear matrix inequalities (LMIs). The explicit expression of the controller gain matrices are parameterized based on the solvability conditions such that the drive system and the response system can be exponentially synchronized. A numerical example is included to illustrate the applicability of the proposed design method.

Dependence of wavelength of Xe ion-induced rippled structures on the fluence in the medium ion energy range

Energy Technology Data Exchange (ETDEWEB)

Hanisch, Antje; Grenzer, Joerg [Institute of Ion Beam Physics and Materials Research, Dresden (Germany); Biermanns, Andreas; Pietsch, Ullrich [Institute of Physics, University of Siegen (Germany)

2010-07-01

Ion-beam eroded self-organized nanostructures on semiconductors offer new ways for the fabrication of high density memory and optoelectronic devices. It is known that wavelength and amplitude of noble gas ion-induced rippled structures tune with the ion energy and the fluence depending on the energy range, ion type and substrate. The linear theory by Makeev predicts a linear dependence of the ion energy on the wavelength for low temperatures. For Ar{sup +} and O{sub 2}{sup +} it was observed by different groups that the wavelength grows with increasing fluence after being constant up to an onset fluence and before saturation. In this coarsening regime power-law or exponential behavior of the wavelength with the fluence was monitored. So far, investigations for Xe ions on silicon surfaces mainly concentrated on energies below 1 keV. We found a linear dependence of both the ion energy and the fluence on the wavelength and amplitude of rippled structures over a wide range of the Xe{sup +} ion energy between 5 and 70 keV. Moreover, we estimated the ratio of wavelength to amplitude to be constant meaning a shape stability when a threshold fluence of 2.10{sup 17} cm{sup -2} was exceeded.

On the Full-range β Dependence of Ion-scale Spectral Break in the Solar Wind Turbulence

Science.gov (United States)

Wang, Xin; Tu, Chuanyi; He, Jiansen; Wang, Linghua

2018-04-01

The power spectrum of magnetic fluctuations has a break at the high-frequency end of the inertial range. Beyond this break, the spectrum becomes steeper than the Kolmogorov law f ‑5/3. The break frequency was found to be associated with plasma beta (β). However, the full-range β dependence of the ion-scale spectral break has not been presented before in observational studies. Here we show the continuous variation of the break frequency on full-range β in the solar wind turbulence. By using measurements from the WIND and Ulysses spacecraft, we show the break frequency (f b ) normalized, respectively, by the frequencies corresponding to ion inertial length (f di ), ion gyroradius ({f}ρ i), and cyclotron resonance scale (f ri ) as a function of β for 1306 intervals. Their β values spread from 0.005 to 20, which nearly covers the full β range of the observed solar wind turbulence. It is found that {f}b/{f}{di} ({f}b/{f}ρ i) generally decreases (increases) with β, while {f}b/{f}{ri} is nearly a constant. We perform a linear fit on the statistical result, and obtain the empirical formulas {f}b/{f}{di}∼ {β }-1/4, {f}b/{f}ρ i∼ {β }1/4, and {f}b/{f}{ri}∼ 0.90 to describe the relation between f b and β. We also compare our observations with a numerical simulation and the prediction by ion cyclotron resonance theory. Our result favors the idea that the cyclotron resonance is an important mechanism for energy dissipation at the spectral break. When β ≪ 1 and β ≫ 1, the break at f di and {f}ρ i may also be associated with other processes.

Temperature Dependence of Short-Range Order in β-Brass

DEFF Research Database (Denmark)

Dietrich, O.W.; Als-Nielsen, Jens Aage

1967-01-01

Critical scattering of neutrons around the superlattice reflections (1, 0, 0) and (1, 1, 1) from a single crystal of beta-brass has been measured at temperatures from 2 to 25deg C above the transition temperature. The temperature dependence of the critical peak intensity, proportional to the susc......Critical scattering of neutrons around the superlattice reflections (1, 0, 0) and (1, 1, 1) from a single crystal of beta-brass has been measured at temperatures from 2 to 25deg C above the transition temperature. The temperature dependence of the critical peak intensity, proportional...

Variability of Diurnal Temperature Range During Winter Over Western Himalaya: Range- and Altitude-Wise Study

Science.gov (United States)

Shekhar, M. S.; Devi, Usha; Dash, S. K.; Singh, G. P.; Singh, Amreek

2018-04-01

The current trends in diurnal temperature range, maximum temperature, minimum temperature, mean temperature, and sun shine hours over different ranges and altitudes of Western Himalaya during winter have been studied. Analysis of 25 years of data shows an increasing trend in diurnal temperature range over all the ranges and altitudes of Western Himalaya during winter, thereby confirming regional warming of the region due to present climate change and global warming. Statistical studies show significant increasing trend in maximum temperature over all the ranges and altitudes of Western Himalaya. Minimum temperature shows significant decreasing trend over Pir Panjal and Shamshawari range and significant increasing trend over higher altitude of Western Himalaya. Similarly, sunshine hours show significant decreasing trend over Karakoram range. There exists strong positive correlation between diurnal temperature range and maximum temperature for all the ranges and altitudes of Western Himalaya. Strong negative correlation exists between diurnal temperature range and minimum temperature over Shamshawari and Great Himalaya range and lower altitude of Western Himalaya. Sunshine hours show strong positive correlation with diurnal temperature range over Pir Panjal and Great Himalaya range and lower and higher altitudes.

Concentration and temperature dependence of short-range order in Ni-Ta solid solution using X-ray diffraction method

International Nuclear Information System (INIS)

Khwaja, F.A.; Alam, A.

1980-09-01

Diffuse X-ray scattering investigations about the existence of short-range order (SRO) have been carried out in the Ni-Ta system for different concentrations and annealing temperatures. It is observed that the values of the SRO parameters for the first co-ordination shell have anomalously large negative values for all the samples studied. These values of the α 1 depend upon the annealing temperatures and the concentration of Ta atoms in the Ni-Ta system. The results of the theoretical predictions of the ordering potential obtained using the formulae of the electronic theory of SRO, confirm the existence of very strong attractive correlation between the atoms of the different species in this system. (author)

Energy dependence of the zero-range DWBA normalization of the /sup 58/Ni(/sup 3/He,. cap alpha. )/sup 57/Ni reaction. [15 to 205 GeV, finite-range and nonlocality corrections

Energy Technology Data Exchange (ETDEWEB)

Shepard, J R; Zimmerman, W R; Kraushaar, J J [Colorado Univ., Boulder (USA). Dept. of Physics and Astrophysics

1977-01-04

Strong transitions in the /sup 58/Ni(/sup 3/He,..cap alpha..)/sup 57/Ni reaction were analyzed using both the zero-range and exact finite-range DWBA. Data considered covered a range of bombarding energies from 15 to 205 MeV. The zero-range DWBA described all data well when finite-range and non-locality corrections were included in the local energy approximation. Comparison of zero-range and exact finite-range calculations showed the local energy approximation correction to be very accurate over the entire energy region. Empirically determined D/sub 0/ values showed no energy dependence. A theoretical D/sub 0/ value calculated using an ..cap alpha.. wave function which reproduced the measured ..cap alpha.. rms charge radius and the elastic electron scattering form factor agreed well the empirical values. Comparison was made between these values and D/sub 0/ values quoted previously in the literature.

Numerical study of the glass-glass transition in short-ranged attractive colloids

International Nuclear Information System (INIS)

Zaccarelli, Emanuela; Sciortino, Francesco; Tartaglia, Piero

2004-01-01

We report extensive numerical simulations in the glass region for a simple model of short-ranged attractive colloids, the square well model. We investigate the behaviour of the density autocorrelation function and of the static structure factor in the region of temperatures and packing fractions where a glass-glass transition is expected according to theoretical predictions. We strengthen our observations by studying both waiting time and history dependence of the numerical results. We provide evidence supporting the possibility that activated bond-breaking processes destabilize the attractive glass, preventing the full observation of a sharp glass-glass kinetic transition

Social, state-dependent and environmental modulation of faecal corticosteroid levels in free-ranging female spotted hyenas.

Science.gov (United States)

Goymann, W; East, M L; Wachter, B; Höner, O P; Möstl, E; Van't Hof, T J; Hofer, H

2001-12-07

Little is known about to what extent the sensitivity of the hypothalamic-pituitary-adrenal (HPA) axis may be state dependent and vary in the same species between environments. Here we tested whether the faecal corticosteroid concentrations of matrilineal adult female spotted hyenas are influenced by social and reproductive status in adjacent ecosystems and whether they vary between periods with and without social stress. Females in the Serengeti National Park frequently become socially subordinate intruders in other hyena territories by undertaking long-distance foraging trips to migratory herds, whereas in the Ngorongoro Crater they usually forage inside their own small territories on resident prey. The faecal corticosteroid concentrations in Serengeti females were significantly higher than in Ngorongoro females. Energy expenditure by lactation is exceptionally high in spotted hyenas and this may be reflected in their corticosteroid levels. The faecal corticosteroid levels in both populations were higher in lactating than in non-lactating females. During periods of social stability, faecal corticosteroid concentrations increased in non-lactating females but not in lactating females as social status declined. Lactating Serengeti females had significantly higher faecal corticosteroid concentrations during periods with acute severe social stress than during periods without, indicating that the HPA axis is sensitive to social stimuli even in lactating females. So far few studies have used non-invasive monitoring methods for assessing social stress in freeranging animals. This study demonstrates for the first time, to the authors' knowledge, that corticosteroid concentrations may differ between periods with and without social stress for a free-ranging female mammal and that the modulating effect of social status may depend on reproductive status.

Temperature dependence of the short-range order parameter and the concentration dependence of the order disorder temperature for Ni-Pt and Ni-Fe systems in the improved statistical pseudopotential approximation

International Nuclear Information System (INIS)

Khwaja, F.A.

1980-08-01

The calculations for the temperature dependence of the first shell short-range order (SRO) parameter for Ni 3 Fe using the cubic approximation of Tahir Kheli, and the concentration dependence of order-disorder temperature Tsub(c) for Ni-Fe and Ni-Pt systems using the linear approximation, have been carried out in the framework of pseudopotential theory. It is shown that the cubic approximation yields a good agreement between the theoretical prediction of the α 1 and the experimental data. Results for the concentration dependence of the Tsub(c) show that improvements in the statistical pseudo-potential approach are essential to achieve a good agreement with experiment. (author)

Spin-Dependent Transport through Chiral Molecules Studied by Spin-Dependent Electrochemistry

Science.gov (United States)

2016-01-01

Conspectus Molecular spintronics (spin + electronics), which aims to exploit both the spin degree of freedom and the electron charge in molecular devices, has recently received massive attention. Our recent experiments on molecular spintronics employ chiral molecules which have the unexpected property of acting as spin filters, by way of an effect we call “chiral-induced spin selectivity” (CISS). In this Account, we discuss new types of spin-dependent electrochemistry measurements and their use to probe the spin-dependent charge transport properties of nonmagnetic chiral conductive polymers and biomolecules, such as oligopeptides, L/D cysteine, cytochrome c, bacteriorhodopsin (bR), and oligopeptide-CdSe nanoparticles (NPs) hybrid structures. Spin-dependent electrochemical measurements were carried out by employing ferromagnetic electrodes modified with chiral molecules used as the working electrode. Redox probes were used either in solution or when directly attached to the ferromagnetic electrodes. During the electrochemical measurements, the ferromagnetic electrode was magnetized either with its magnetic moment pointing “UP” or “DOWN” using a permanent magnet (H = 0.5 T), placed underneath the chemically modified ferromagnetic electrodes. The spin polarization of the current was found to be in the range of 5–30%, even in the case of small chiral molecules. Chiral films of the l- and d-cysteine tethered with a redox-active dye, toludin blue O, show spin polarizarion that depends on the chirality. Because the nickel electrodes are susceptible to corrosion, we explored the effect of coating them with a thin gold overlayer. The effect of the gold layer on the spin polarization of the electrons ejected from the electrode was investigated. In addition, the role of the structure of the protein on the spin selective transport was also studied as a function of bias voltage and the effect of protein denaturation was revealed. In addition to �

On the long-range dependence properties of annual precipitation using a global network of instrumental measurements

Science.gov (United States)

Tyralis, Hristos; Dimitriadis, Panayiotis; Koutsoyiannis, Demetris; O'Connell, Patrick Enda; Tzouka, Katerina; Iliopoulou, Theano

2018-01-01

The long-range dependence (LRD) is considered an inherent property of geophysical processes, whose presence increases uncertainty. Here we examine the spatial behaviour of LRD in precipitation by regressing the Hurst parameter estimate of mean annual precipitation instrumental data which span from 1916-2015 and cover a big area of the earth's surface on location characteristics of the instrumental data stations. Furthermore, we apply the Mann-Kendall test under the LRD assumption (MKt-LRD) to reassess the significance of observed trends. To summarize the results, the LRD is spatially clustered, it seems to depend mostly on the location of the stations, while the predictive value of the regression model is good. Thus when investigating for LRD properties we recommend that the local characteristics should be considered. The application of the MKt-LRD suggests that no significant monotonic trend appears in global precipitation, excluding the climate type D (snow) regions in which positive significant trends appear.

Temperature dependence of the Schottky-barrier heights of n-type semiconductors in the temperature range of 7 to 300 K

International Nuclear Information System (INIS)

Chen, T.P.; Lee, T.C.; Fung, S.; Beling, C.D.

1994-01-01

In this note we present the results of the temperature dependence of the SBH in Au/n-Si, Ag/n-GaAs, and Au/n-GaAs in the temperature range of 7 to 300 K from our internal photoemission measurements. (orig.)

Natural course of care dependency in residents of long-term care facilities: prospective follow-up study.

Science.gov (United States)

Caljouw, Monique A A; Cools, Herman J M; Gussekloo, Jacobijn

2014-05-22

Insight in the natural course of care dependency of vulnerable older persons in long-term care facilities (LTCF) is essential to organize and optimize individual tailored care. We examined changes in care dependency in LTCF residents over two 6-month periods, explored the possible predictive factors of change and the effect of care dependency on mortality. A prospective follow-up study in 21 Dutch long-term care facilities. 890 LTCF residents, median age 84 (Interquartile range 79-88) years participated. At baseline, 6 and 12 months, care dependency was assessed by the nursing staff with the Care Dependency Scale (CDS), range 15-75 points. Since the median CDS score differed between men and women (47.5 vs. 43.0, P = 0.013), CDS groups (low, middle and high) were based on gender-specific 33% of CDS scores at baseline and 6 months. At baseline, the CDS groups differed in median length of stay on the ward, urine incontinence and dementia (all P dependency status, predicted an increase in care dependency over time. The majority of residents were stable in their care dependency status over two subsequent 6-month periods. Highly care dependent residents showed an increased mortality risk. Awareness of the natural course of care dependency is essential to residents and their formal and informal caregivers when considering therapeutic and end-of-life care options.

Study of the effect of short ranged ordering on the magnetism in FeCr alloys

Energy Technology Data Exchange (ETDEWEB)

Jena, Ambika Prasad, E-mail: apjena@bose.res.in [Department of Condensed Matter and Materials Science, S N Bose National Centre for Basic Sciences, JD Block, Sector III, Salt Lake City, Kolkata 700098 (India); Sanyal, Biplab, E-mail: biplab.sanyal@physics.uu.se [Department of Physics and Astronomy, Uppsala University, Box 516, SE-75120 Uppsala (Sweden); Mookerjee, Abhijit, E-mail: abhijit.mookerjee61@gmail.com [Department of Condensed Matter and Materials Science, S N Bose National Centre for Basic Sciences, JD Block, Sector III, Salt Lake City, Kolkata 700098 (India)

2014-01-15

For the study of magnetism in systems where the local environment plays an important role, we propose a marriage between the Monte Carlo simulation and Zunger's special quasi-random structures. We apply this technique on disordered FeCr alloys and show that our estimates of the transition temperature is in good agreement with earlier experiments. - Highlights: • The magnetism in FeCr is sensitively depended on the ordering of the atoms : disordered or with short ranged ordering. • This work uses the SQS technique suggested by Zunger has been used to generate various degrees of short range ordering in FeCr. • The electronic structure and pair energies have been obatined from first principles ASR and Lichtenstein methods. • The effect of chemical ordering on magnetic ordering is studied in detail. • Only those situations where the chemical ordering is complete have been studied.

Study of the effect of short ranged ordering on the magnetism in FeCr alloys

International Nuclear Information System (INIS)

Jena, Ambika Prasad; Sanyal, Biplab; Mookerjee, Abhijit

2014-01-01

For the study of magnetism in systems where the local environment plays an important role, we propose a marriage between the Monte Carlo simulation and Zunger's special quasi-random structures. We apply this technique on disordered FeCr alloys and show that our estimates of the transition temperature is in good agreement with earlier experiments. - Highlights: • The magnetism in FeCr is sensitively depended on the ordering of the atoms : disordered or with short ranged ordering. • This work uses the SQS technique suggested by Zunger has been used to generate various degrees of short range ordering in FeCr. • The electronic structure and pair energies have been obatined from first principles ASR and Lichtenstein methods. • The effect of chemical ordering on magnetic ordering is studied in detail. • Only those situations where the chemical ordering is complete have been studied

Self-produced Time Intervals Are Perceived as More Variable and/or Shorter Depending on Temporal Context in Subsecond and Suprasecond Ranges

Directory of Open Access Journals (Sweden)

Keita eMitani

2016-06-01

Full Text Available The processing of time intervals is fundamental for sensorimotor and cognitive functions. Perceptual and motor timing are often performed concurrently (e.g., playing a musical instrument. Although previous studies have shown the influence of body movements on time perception, how we perceive self-produced time intervals has remained unclear. Furthermore, it has been suggested that the timing mechanisms are distinct for the sub- and suprasecond ranges. Here, we compared perceptual performances for self-produced and passively presented time intervals in random contexts (i.e., multiple target intervals presented in a session across the sub- and suprasecond ranges (Experiment 1 and within the sub- (Experiment 2 and suprasecond (Experiment 3 ranges, and in a constant context (i.e., a single target interval presented in a session in the sub- and suprasecond ranges (Experiment 4. We show that self-produced time intervals were perceived as shorter and more variable across the sub- and suprasecond ranges and within the suprasecond range but not within the subsecond range in a random context. In a constant context, the self-produced time intervals were perceived as more variable in the suprasecond range but not in the subsecond range. The impairing effects indicate that motor timing interferes with perceptual timing. The dependence of impairment on temporal contexts suggests multiple timing mechanisms for the subsecond and suprasecond ranges. In addition, violation of the scalar property (i.e., a constant variability to target interval ratio was observed between the sub- and suprasecond ranges. The violation was clearer for motor timing than for perceptual timing. This suggests that the multiple timing mechanisms for the sub- and suprasecond ranges overlap more for perception than for motor. Moreover, the central tendency effect (i.e., where shorter base intervals are overestimated and longer base intervals are underestimated disappeared with subsecond

Study of the temperature dependence of giant magnetoresistance in metallic granular composite

International Nuclear Information System (INIS)

Ju Sheng; Li, Z.-Y.

2002-01-01

The temperature dependence of the giant magnetoresistance of metallic granular composite is studied. It is considered that the composite contains both large magnetic grains with surface spin S' and small magnetic impurities. It is found that the decrease of surface spin S' of grain is the main cause of an almost linear decrease of giant magnetoresistance with the increase of temperature in high temperature range. The magnetic impurities, composed of several atoms, lead to an almost linear increase of the giant magnetoresistance with the decrease of temperature in low temperature range. Our calculations are in good agreement with recent experimental data for metallic nanogranular composites

CO ICE PHOTODESORPTION: A WAVELENGTH-DEPENDENT STUDY

International Nuclear Information System (INIS)

Fayolle, Edith C.; Linnartz, Harold; Bertin, Mathieu; Romanzin, Claire; Michaut, Xavier; Fillion, Jean-Hugues; Oeberg, Karin I.

2011-01-01

UV-induced photodesorption of ice is a non-thermal evaporation process that can explain the presence of cold molecular gas in a range of interstellar regions. Information on the average UV photodesorption yield of astrophysically important ices exists for broadband UV lamp experiments. UV fields around low-mass pre-main-sequence stars, around shocks and in many other astrophysical environments are however often dominated by discrete atomic and molecular emission lines. It is therefore crucial to consider the wavelength dependence of photodesorption yields and mechanisms. In this work, for the first time, the wavelength-dependent photodesorption of pure CO ice is explored between 90 and 170 nm. The experiments are performed under ultra high vacuum conditions using tunable synchrotron radiation. Ice photodesorption is simultaneously probed by infrared absorption spectroscopy in reflection mode of the ice and by quadrupole mass spectrometry of the gas phase. The experimental results for CO reveal a strong wavelength dependence directly linked to the vibronic transition strengths of CO ice, implying that photodesorption is induced by electronic transition (DIET). The observed dependence on the ice absorption spectra implies relatively low photodesorption yields at 121.6 nm (Lyα), where CO barely absorbs, compared to the high yields found at wavelengths coinciding with transitions into the first electronic state of CO (A 1 Π at 150 nm); the CO photodesorption rates depend strongly on the UV profiles encountered in different star formation environments.

Range-separated density-functional theory for molecular excitation energies

International Nuclear Information System (INIS)

Rebolini, E.

2014-01-01

Linear-response time-dependent density-functional theory (TDDFT) is nowadays a method of choice to compute molecular excitation energies. However, within the usual adiabatic semi-local approximations, it is not able to describe properly Rydberg, charge-transfer or multiple excitations. Range separation of the electronic interaction allows one to mix rigorously density-functional methods at short range and wave function or Green's function methods at long range. When applied to the exchange functional, it already corrects most of these deficiencies but multiple excitations remain absent as they need a frequency-dependent kernel. In this thesis, the effects of range separation are first assessed on the excitation energies of a partially-interacting system in an analytic and numerical study in order to provide guidelines for future developments of range-separated methods for excitation energy calculations. It is then applied on the exchange and correlation TDDFT kernels in a single-determinant approximation in which the long-range part of the correlation kernel vanishes. A long-range frequency-dependent second-order correlation kernel is then derived from the Bethe-Salpeter equation and added perturbatively to the range-separated TDDFT kernel in order to take into account the effects of double excitations. (author)

History-dependent friction and slow slip from time-dependent microscopic junction laws studied in a statistical framework.

Science.gov (United States)

Thøgersen, Kjetil; Trømborg, Jørgen Kjoshagen; Sveinsson, Henrik Andersen; Malthe-Sørenssen, Anders; Scheibert, Julien

2014-05-01

To study how macroscopic friction phenomena originate from microscopic junction laws, we introduce a general statistical framework describing the collective behavior of a large number of individual microjunctions forming a macroscopic frictional interface. Each microjunction can switch in time between two states: a pinned state characterized by a displacement-dependent force and a slipping state characterized by a time-dependent force. Instead of tracking each microjunction individually, the state of the interface is described by two coupled distributions for (i) the stretching of pinned junctions and (ii) the time spent in the slipping state. This framework allows for a whole family of microjunction behavior laws, and we show how it represents an overarching structure for many existing models found in the friction literature. We then use this framework to pinpoint the effects of the time scale that controls the duration of the slipping state. First, we show that the model reproduces a series of friction phenomena already observed experimentally. The macroscopic steady-state friction force is velocity dependent, either monotonic (strengthening or weakening) or nonmonotonic (weakening-strengthening), depending on the microscopic behavior of individual junctions. In addition, slow slip, which has been reported in a wide variety of systems, spontaneously occurs in the model if the friction contribution from junctions in the slipping state is time weakening. Next, we show that the model predicts a nontrivial history dependence of the macroscopic static friction force. In particular, the static friction coefficient at the onset of sliding is shown to increase with increasing deceleration during the final phases of the preceding sliding event. We suggest that this form of history dependence of static friction should be investigated in experiments, and we provide the acceleration range in which this effect is expected to be experimentally observable.

Dependence of four-body observables on the range of UPA-like effective interactions

International Nuclear Information System (INIS)

Perne, R.; Sandhas, W.

1977-07-01

A generalized unitary pole approximation (UPA) concerning the three-body amplitudes in the kernel of four-body integral equations is introduced. We furhtermore study the dependence of the 4 He binding energy and of four-body cross sections upon a position space cut-off parameter in the effective interactions. (orig.) [de

Statistical modeling of the long-range-dependent structure of barrier island framework geology and surface geomorphology

Directory of Open Access Journals (Sweden)

B. A. Weymer

2018-06-01

Full Text Available Shorelines exhibit long-range dependence (LRD and have been shown in some environments to be described in the wave number domain by a power-law characteristic of scale independence. Recent evidence suggests that the geomorphology of barrier islands can, however, exhibit scale dependence as a result of systematic variations in the underlying framework geology. The LRD of framework geology, which influences island geomorphology and its response to storms and sea level rise, has not been previously examined. Electromagnetic induction (EMI surveys conducted along Padre Island National Seashore (PAIS, Texas, United States, reveal that the EMI apparent conductivity (σa signal and, by inference, the framework geology exhibits LRD at scales of up to 101 to 102 km. Our study demonstrates the utility of describing EMI σa and lidar spatial series by a fractional autoregressive integrated moving average (ARIMA process that specifically models LRD. This method offers a robust and compact way of quantifying the geological variations along a barrier island shoreline using three statistical parameters (p, d, q. We discuss how ARIMA models that use a single parameter d provide a quantitative measure for determining free and forced barrier island evolutionary behavior across different scales. Statistical analyses at regional, intermediate, and local scales suggest that the geologic framework within an area of paleo-channels exhibits a first-order control on dune height. The exchange of sediment amongst nearshore, beach, and dune in areas outside this region are scale independent, implying that barrier islands like PAIS exhibit a combination of free and forced behaviors that affect the response of the island to sea level rise.

Statistical modeling of the long-range-dependent structure of barrier island framework geology and surface geomorphology

Science.gov (United States)

Weymer, Bradley A.; Wernette, Phillipe; Everett, Mark E.; Houser, Chris

2018-06-01

Shorelines exhibit long-range dependence (LRD) and have been shown in some environments to be described in the wave number domain by a power-law characteristic of scale independence. Recent evidence suggests that the geomorphology of barrier islands can, however, exhibit scale dependence as a result of systematic variations in the underlying framework geology. The LRD of framework geology, which influences island geomorphology and its response to storms and sea level rise, has not been previously examined. Electromagnetic induction (EMI) surveys conducted along Padre Island National Seashore (PAIS), Texas, United States, reveal that the EMI apparent conductivity (σa) signal and, by inference, the framework geology exhibits LRD at scales of up to 101 to 102 km. Our study demonstrates the utility of describing EMI σa and lidar spatial series by a fractional autoregressive integrated moving average (ARIMA) process that specifically models LRD. This method offers a robust and compact way of quantifying the geological variations along a barrier island shoreline using three statistical parameters (p, d, q). We discuss how ARIMA models that use a single parameter d provide a quantitative measure for determining free and forced barrier island evolutionary behavior across different scales. Statistical analyses at regional, intermediate, and local scales suggest that the geologic framework within an area of paleo-channels exhibits a first-order control on dune height. The exchange of sediment amongst nearshore, beach, and dune in areas outside this region are scale independent, implying that barrier islands like PAIS exhibit a combination of free and forced behaviors that affect the response of the island to sea level rise.

A comparative study of self-regulation in substance dependent and non-dependent individuals.

Science.gov (United States)

Bakhshani, Nour Mohammad; Hosseinbor, Mohsen

2013-08-05

Several factors influence the beginning and maintenance of substance use. The purpose of this study was to examine as well as to compare 'self-regulation' in both substance dependent and non-substance dependent individuals. In a cross-sectional study 228 (118 substance dependent and 110 with no history of using substance) participants aged 16-55 were recruited. All of the participants were asked to complete the Self-Regulation Inventory (SRI-25) and a demographic characteristics data checklist. Data was analyzed using descriptive statistics (frequency, mean and standard deviation) and the t-test. The results showed significant differences between substance dependent and non- substance dependent groups in all the scales of the self-regulation inventory including positive actions, controllability, expression of feelings and needs, assertiveness, and well-being seeking (p<0.01). Self-regulation and self-control skills in drug dependent individuals are lower than those without substance dependence individuals. It is concluded that substance use may related to a deficiency in self-control and regulation of feelings. Therefore, for prevention and treatment of substance dependence disorder, it is necessary to work out and exploit strategies that include the improvement of self-regulation.

Comparison of three different concepts of high dynamic range and dependability optimised current measurement digitisers for beam loss systems

CERN Document Server

Viganò, W; Effinger, E; Venturini, G G; Zamantzas, C

2012-01-01

Three Different Concepts of High Dynamic Range and Dependability Optimised Current Measurement Digitisers for Beam Loss Systems will be compared on this paper. The first concept is based on Current to Frequency Conversion, enhanced with an ADC for extending the dynamic range and decreasing the response time. A summary of 3 years’ worth of operational experience with such a system for LHC beam loss monitoring will be given. The second principle is based on an Adaptive Current to Frequency Converter implemented in an ASIC. The basic parameters of the circuit are discussed and compared with measurements. Several measures are taken to harden both circuits against single event effects and to make them tolerant for operation in radioactive environments. The third circuit is based on a Fully Differential Integrator for enhanced dynamic range, where laboratory and test installation measurements will be presented. All circuits are designed to avoid any dead time in the acquisition and have reliability and fail safe...

Quantifying the range of cross-correlated fluctuations using a q- L dependent AHXA coefficient

Science.gov (United States)

Wang, Fang; Wang, Lin; Chen, Yuming

2018-03-01

Recently, based on analogous height cross-correlation analysis (AHXA), a cross-correlation coefficient ρ×(L) has been proposed to quantify the levels of cross-correlation on different temporal scales for bivariate series. A limitation of this coefficient is that it cannot capture the full information of cross-correlations on amplitude of fluctuations. In fact, it only detects the cross-correlation at a specific order fluctuation, which might neglect some important information inherited from other order fluctuations. To overcome this disadvantage, in this work, based on the scaling of the qth order covariance and time delay L, we define a two-parameter dependent cross-correlation coefficient ρq(L) to detect and quantify the range and level of cross-correlations. This new version of ρq(L) coefficient leads to the formation of a ρq(L) surface, which not only is able to quantify the level of cross-correlations, but also allows us to identify the range of fluctuation amplitudes that are correlated in two given signals. Applications to the classical ARFIMA models and the binomial multifractal series illustrate the feasibility of this new coefficient ρq(L) . In addition, a statistical test is proposed to quantify the existence of cross-correlations between two given series. Applying our method to the real life empirical data from the 1999-2000 California electricity market, we find that the California power crisis in 2000 destroys the cross-correlation between the price and the load series but does not affect the correlation of the load series during and before the crisis.

Degeneracy and long-range correlation: A simulation study

Directory of Open Access Journals (Sweden)

Marmelat Vivien

2011-12-01

Full Text Available We present in this paper a simulation study that aimed at evidencing a causal relationship between degeneracy and long-range correlations. Long-range correlations represent a very specific form of fluctuations that have been evidenced in the outcomes time series produced by a number of natural systems. Long-range correlations are supposed to sign the complexity, adaptability and flexibility of the system. Degeneracy is defined as the ability of elements that are structurally different to perform the same function, and is presented as a key feature for explaining the robustness of complex systems. We propose a model able to generate long-range correlated series, and including a parameter that account for degeneracy. Results show that a decrease in degeneracy tends to reduce the strength of long-range correlation in the series produced by the model.

Positional short-range order in the nematic phase of n BABAs

Science.gov (United States)

Usha Deniz, K.; Pepy, G.; Parette, G.; Keller, P.

1991-10-01

The positional short-range order, SRO ⊥, perpendicular to the nematic director n̂ has been studied in the fibre-type nematics, nBABAs, by neutron diffraction. SRO ⊥ is found to be dependent on other types of nematic short-range order but not on the orientational long-range order.

Short-range fundamental forces

International Nuclear Information System (INIS)

Antoniadis, I.; Baessler, S.; Buchner, M.; Fedorov, V.V.; Hoedl, S.; Nesvizhevsky, V.V.; Pignol, G.; Protasov, K.V.; Lambrecht, A.; Reynaud, S.; Sobolev, Y.

2010-01-01

We consider theoretical motivations to search for extra short-range fundamental forces as well as experiments constraining their parameters. The forces could be of two types: 1) spin-independent forces; 2) spin-dependent axion-like forces. Different experimental techniques are sensitive in respective ranges of characteristic distances. The techniques include measurements of gravity at short distances, searches for extra interactions on top of the Casimir force, precision atomic and neutron experiments. We focus on neutron constraints, thus the range of characteristic distances considered here corresponds to the range accessible for neutron experiments

Long-range dependence in returns and volatility of global gold market amid financial crises

Science.gov (United States)

Omane-Adjepong, Maurice; Boako, Gideon

2017-04-01

Using sampled historical daily gold market data from 07-03-1985 to 06-01-2015, and building on a related work by Bentes (2016), this paper examines the presence of long-range dependence (LRD) in the world's gold market returns and volatility, accounting for structural breaks. The sampled gold market data was divided into subsamples based on four global crises: the September 1992 collapse of the European Exchange Rate Mechanism (ERM), the Asian financial crisis of mid-1997, the Subprime meltdown of 2007, and the recent European sovereign debt crisis, which hit the world's market with varying effects. LRD test was carried-out on the full-sample and subsample periods using three semiparametric methods-before and after adjusting for structural breaks. The results show insignificant evidence of LRD in gold returns. However, very diminutive evidence is found for periods characterized by financial/economic shocks, with no significant detections for post-shock periods. Collectively, this is indicative that the gold market is less speculative, and hence could be somehow less risky for hedging and portfolio diversification.

Spectral long-range interaction of temporal incoherent solitons.

Science.gov (United States)

Xu, Gang; Garnier, Josselin; Picozzi, Antonio

2014-02-01

We study the interaction of temporal incoherent solitons sustained by a highly noninstantaneous (Raman-like) nonlinear response. The incoherent solitons exhibit a nonmutual interaction, which can be either attractive or repulsive depending on their relative initial distance. The analysis reveals that incoherent solitons exhibit a long-range interaction in frequency space, which is in contrast with the expected spectral short-range interaction described by the usual approach based on the Raman-like spectral gain curve. Both phenomena of anomalous interaction and spectral long-range behavior of incoherent solitons are described in detail by a long-range Vlasov equation.

Examples and applications in long-range ocean acoustics

International Nuclear Information System (INIS)

Vera, M D

2007-01-01

Acoustic energy propagates effectively to long ranges in the ocean interior because of the physical properties of the marine environment. Sound propagation in the ocean is relevant to a variety of studies in communication, climatology and marine biology. Examples drawn from ocean acoustics, therefore, are compelling to students with a variety of interests. The dependence of sound speed on depth results in a waveguide that permits the detection of acoustic energy at ranges, in some experiments, of thousands of kilometres. This effect serves as an illustration of Snell's law with a continuously variable index of refraction. Acoustic tomography also offers a means for imaging the ocean's thermal structure, because of the dependence of sound speed on temperature. The ability to perform acoustic thermometry for large transects of the ocean provides an effective means of studying climate change. This application in an area of substantial popular attention allows for an effective introduction to concepts in ray propagation. Aspects of computational ocean acoustics can be productive classroom examples in courses ranging from introductory physics to upper-division mathematical methods courses

One-dimensional long-range percolation: A numerical study

Science.gov (United States)

Gori, G.; Michelangeli, M.; Defenu, N.; Trombettoni, A.

2017-07-01

In this paper we study bond percolation on a one-dimensional chain with power-law bond probability C /rd +σ , where r is the distance length between distinct sites and d =1 . We introduce and test an order-N Monte Carlo algorithm and we determine as a function of σ the critical value Cc at which percolation occurs. The critical exponents in the range 0 values for Cc are compared with a known exact bound, while the critical exponent ν is compared with results from mean-field theory, from an expansion around the point σ =1 and from the ɛ -expansion used with the introduction of a suitably defined effective dimension deff relating the long-range model with a short-range one in dimension deff. We finally present a formulation of our algorithm for bond percolation on general graphs, with order N efficiency on a large class of graphs including short-range percolation and translationally invariant long-range models in any spatial dimension d with σ >0 .

A study on alpha particles range in Cr-39

International Nuclear Information System (INIS)

Ibrahim, Z.A.; Talaat, T.M.; Abdel-Aziz, Kh.M.A.; El-Asser, M.R.

2000-01-01

Cr-39 plastic nuclear track detector has been used in range determination of alpha particles. A set of experiments was carried out for studying alpha energy and track diameter relationships. This work was done under the optimum conditions of Cr-39 etching in 6.25 N NaOH at 70 degree C for various etching times. Determination of alpha range in Cr-39 recorders was studied at different energy values using the over etched track profile technique. Data are discussed within the framework of track formation theory in plastic foils, comparison between experimental and theoretical values of alpha range is included

Kinetic study of time-dependent fixation of U{sup VI} on biochar

Energy Technology Data Exchange (ETDEWEB)

Ashry, A. [Division of Agricultural and Environmental Sciences, School of Biosciences, University of Nottingham, Sutton Bonington, Leicestershire LE12 5RD (United Kingdom); Radiation Protection Department, Nuclear Research Centre, Egyptian Atomic Energy Authority, Cairo (Egypt); Bailey, E.H., E-mail: liz.bailey@nottingham.ac.uk [Division of Agricultural and Environmental Sciences, School of Biosciences, University of Nottingham, Sutton Bonington, Leicestershire LE12 5RD (United Kingdom); Chenery, S.R.N. [British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG (United Kingdom); Young, S.D. [Division of Agricultural and Environmental Sciences, School of Biosciences, University of Nottingham, Sutton Bonington, Leicestershire LE12 5RD (United Kingdom)

2016-12-15

Biochar, a by-product from the production of biofuel and syngas by gasification, was tested as a material for adsorption and fixation of U{sup VI} from aqueous solutions. A batch experiment was conducted to study the factors that influence the adsorption and time-dependent fixation on biochar at 20 °C, including pH, initial concentration of U{sup VI} and contact time. Uranium (U{sup VI}) adsorption was highly dependent on pH but adsorption on biochar was high over a wide range of pH values, from 4.5 to 9.0, and adsorption strength was time-dependent over several days. The experimental data for pH > 7 were most effectively modelled using a Freundlich adsorption isotherm coupled to a reversible first order kinetic equation to describe the time-dependent fixation of U{sup VI} within the biochar structure. Desorption experiments showed that U{sup VI} was only sparingly desorbable from the biochar with time and isotopic dilution with {sup 233}U{sup VI} confirmed the low, or time-dependent, lability of adsorbed {sup 238}U{sup VI}. Below pH 7 the adsorption isotherm trend suggested precipitation, rather than true adsorption, may occur. However, across all pH values (4.5-9) measured saturation indices suggested precipitation was possible: autunite below pH 6.5 and either swartzite, liebigite or bayleyite above pH 6.5.

Study of the SEY dependence on the electron beams dose and energy

International Nuclear Information System (INIS)

Commisso, M.

2011-01-01

During operation, the internal walls of modern particle accelerators are subjected to synchrotron radiation irradiation and/or electron bombardment. Such phenomena do affect surface properties such as the secondary electron yield, (SEY). A low SEY is a key parameter to control and overcome any detrimental effect on the accelerator performance eventually induced by the build-up of an Electron Cloud (E C). In laboratory experiments SEY reduction (called scrubbing) has been studied as a function of dose but the actual kinetic energy dependence has never been considered as an important parameter. For this reason and given the peculiar behavior observed for low-energy electrons, we decided to study this dependence accurately. Here we report results of SEY measurements performed bombarding Cu samples obtained from the Large Hadron Collider (Lhc) with different doses of electron beam with energy in the range 10-500 eV. Our results demonstrate that the potentiality of an electron beam to reduce the SEY does not only depend on its dose, but also on its energy. Furthermore, since E C build-up was predicted and observed also the DAΦNE ring, we report some preliminary measurements on the conditioning of Al samples. An overview of future experiments which we will perform in LNF is then given.

Temperature dependence of stress in CVD diamond films studied by Raman spectroscopy

Directory of Open Access Journals (Sweden)

Dychalska Anna

2015-09-01

Full Text Available Evolution of residual stress and its components with increasing temperature in chemical vapor deposited (CVD diamond films has a crucial impact on their high temperature applications. In this work we investigated temperature dependence of stress in CVD diamond film deposited on Si(100 substrate in the temperature range of 30 °C to 480 °C by Raman mapping measurement. Raman shift of the characteristic diamond band peaked at 1332 cm-1 was studied to evaluate the residual stress distribution at the diamond surface. A new approach was applied to calculate thermal stress evolution with increasing tempera­ture by using two commonly known equations. Comparison of the residts obtained from the two methods was presented. The intrinsic stress component was calculated from the difference between average values of residual and thermal stress and then its temperature dependence was discussed.

Aberrant regional brain activities in alcohol dependence: a functional magnetic resonance imaging study

Directory of Open Access Journals (Sweden)

Tu XZ

2018-03-01

Full Text Available Xianzhu Tu,1 Juanjuan Wang,2 Xuming Liu,3 Jiyong Zheng4 1Department of Psychiatry, Seventh People’s Hospital of Wenzhou City, Wenzhou, Zhejiang, People’s Republic of China; 2Department of Neurology, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, People’s Republic of China; 3Department of Radiology, The Third Clinical Institute Affiliated to Wenzhou Medical University, Wenzhou, Zhejiang, People’s Republic of China; 4Department of Medical Imaging, The Affiliated Huai’an No 1 People’s Hospital of Nanjing Medical University, Huai’an, Jiangsu, People’s Republic of China Objective: Whether moderate alcohol consumption has health benefits remains controversial, but the harmful effects of excessive alcohol consumption on behavior and brain function are well recognized. The aim of this study was to investigate alcohol-induced regional brain activities and their relationships with behavioral factors. Subjects and methods: A total of 29 alcohol-dependent subjects (9 females and 20 males and 29 status-matched healthy controls (11 females and 18 males were recruited. Severity of alcohol dependence questionnaire (SADQ and alcohol use disorders identification test (AUDIT were used to evaluate the severity of alcohol craving. Regional homogeneity (ReHo analysis was used to explore the alcohol-induced regional brain changes. Receiver operating characteristic (ROC curve was used to investigate the ability of regional brain activities to distinguish alcohol-dependent subjects from healthy controls. Pearson correlations were used to investigate the relationships between alcohol-induced ReHo differences and behavioral factors. Results: Alcohol-dependent subjects related to healthy controls showed higher ReHo areas in the right superior frontal gyrus (SFG, bilateral medial frontal gyrus (MFG, left precentral gyrus (PG, bilateral middle temporal gyrus (MTG, and right inferior temporal gyrus (ITG and lower ReHo areas in

Temperature dependence of three-body ion-molecule reactions

International Nuclear Information System (INIS)

Boehringer, H.; Arnold, F.

1983-01-01

The temperature dependence of the ion-molecule association reactions (i) N 2 + + N 2 + M → N 4 + + M (M=N 2 , He), (ii) O 2 + + O 2 + M → O 4 + + M (M=O 2 , He) and (iii) He + + 2He → He 2 + + He have been studied over an extended temperature range to temperatures as low as 30K with a recently constructed liquid helium-cooled ion drift tube. Over most of the temperature range the threebody reaction rate coefficients show an inverse temperature dependence proportional to Tsup(-n) with n in the range 0.6 to 2.9. This temperature dependence is quite consistent with current theories of ion molecule association. At low temperatures, however, a deviation from the Tsup(-n) dependence was observed for the association reactions (ii). For reactions (i) different temperature dependences were obtained for N 2 and He third bodies indicating an additional temperature dependence of the collisional stabilisation process. (Authors)

Experimental study of shear rate dependence in perpetually sheared granular matter

Science.gov (United States)

Liu, Sophie Yang; Guillard, François; Marks, Benjy; Rognon, Pierre; Einav, Itai

2017-06-01

We study the shear behaviour of various granular materials by conducting novel perpetual simple shear experiments over four orders of magnitude of relatively low shear rates. The newly developed experimental apparatus employed is called "3D Stadium Shear Device" which is an extended version of the 2D Stadium Shear Device [1]. This device is able to provide a non-radial dependent perpetual shear flow and a nearly linear velocity profile between two oppositely moving shear walls. Using this device, we are able to test a large variety of granular materials. Here, we demonstrate the applicability of the device on glass beads (diameter 1 mm, 3 mm, and 14 mm) and rice. We particularly focus on studying these materials at very low inertial number I ranging from 10-6 to 10-2. We find that, within this range of I, the friction coefficient μ of glass beads has no shear rate dependence. A particularly appealing observation comes from testing rice, where the attainment of critical state develops under much longer duration than in other materials. Initially during shear we find a value of μ similar to that found for glass beads, but with time this value decreases gradually towards the asymptotic critical state value. The reason, we believe, lies in the fact that rice grains are strongly elongated; hence the time to achieve the stable μ is primarily controlled by the time for particles to align themselves with respect to the shear walls. Furthermore, the initial packing conditions of samples also plays a role in the evolution of μ when the shear strain is small, but that impact will eventually be erased after sufficient shear strain.

Climate driven range divergence among host species affects range-wide patterns of parasitism

Directory of Open Access Journals (Sweden)

Richard E. Feldman

2017-01-01

Full Text Available Species interactions like parasitism influence the outcome of climate-driven shifts in species ranges. For some host species, parasitism can only occur in that part of its range that overlaps with a second host species. Thus, predicting future parasitism may depend on how the ranges of the two hosts change in relation to each other. In this study, we tested whether the climate driven species range shift of Odocoileus virginianus (white-tailed deer accounts for predicted changes in parasitism of two other species from the family Cervidae, Alces alces (moose and Rangifer tarandus (caribou, in North America. We used MaxEnt models to predict the recent (2000 and future (2050 ranges (probabilities of occurrence of the cervids and a parasite Parelaphostrongylus tenuis (brainworm taking into account range shifts of the parasite’s intermediate gastropod hosts. Our models predicted that range overlap between A. alces/R. tarandus and P. tenuis will decrease between 2000 and 2050, an outcome that reflects decreased overlap between A. alces/R. tarandus and O. virginianus and not the parasites, themselves. Geographically, our models predicted increasing potential occurrence of P. tenuis where A. alces/R. tarandus are likely to decline, but minimal spatial overlap where A. alces/R. tarandus are likely to increase. Thus, parasitism may exacerbate climate-mediated southern contraction of A. alces and R. tarandus ranges but will have limited influence on northward range expansion. Our results suggest that the spatial dynamics of one host species may be the driving force behind future rates of parasitism for another host species.

Online gaming dependency: a preliminary study in China.

Science.gov (United States)

Peng, Wei; Liu, Ming

2010-06-01

Based on theories and previous studies on problematic Internet use, we propose a model to better understand the contributors to and consequences of online gaming dependency. A preliminary study was conducted through a survey of online gamers in China. The results of path analysis found that maladaptive cognitions, shyness, and depression are positively related to online gaming dependency. Online gaming dependency was also positively related to different types of negative life outcomes. The findings of this study have implications for the prevention and treatment of addictive online gaming.

Studies on frequency dependent electrical and dielectric properties of sintered zinc oxide pellets: effects of Al-doping

Science.gov (United States)

Tewari, S.; Ghosh, A.; Bhattacharjee, A.

2016-11-01

Sintered pellets of zinc oxide (ZnO), both undoped and Al-doped are prepared through a chemical process. Dopant concentration of Aluminium in ZnO [Al/Zn in weight percentage (wt%)] is varied from 0 to 3 wt%. After synthesis structural characterisation of the samples are performed with XRD and SEM-EDAX which confirm that all the samples are of ZnO having polycrystalline nature with particle size from 108.6 to 116 nm. Frequency dependent properties like a.c. conductivity, capacitance, impedance and phase angle are measured in the frequency range 10 Hz to 100 kHz as a function of temperature (in the range 25-150 °C). Nature of a.c. conductivity in these samples indicates hopping type of conduction arising from localised defect states. The frequency and temperature dependent properties under study are found to be as per correlated barrier hoping model. Dielectric and impedance properties studied in the samples indicate distributed relaxation, showing decrease of relaxation time with temperature.

Netherlands Army Long Range Anti Armour Study - Status Report

OpenAIRE

Schagen, P.A.B. van

1989-01-01

At the end of the nineties the munition for the TOW weapon system in use at The Netherlands army, has to be replaced. The Life of Type of The Tow carrier ends in 2005. The long range anti armour study is to gain insight into the possibilities and limitations for the Netherlands army to deploy future (time period 1995-2000) weapon systems in the long range anti armour battle. The first study results are expected at the end of 1989. The study is sponsored by the Netherlands army and is carried ...

Pacemaker Dependency after Cardiac Surgery: A Systematic Review of Current Evidence.

Science.gov (United States)

Steyers, Curtis M; Khera, Rohan; Bhave, Prashant

2015-01-01

Severe postoperative conduction disturbances requiring permanent pacemaker implantation frequently occur following cardiac surgery. Little is known about the long-term pacing requirements and risk factors for pacemaker dependency in this population. We performed a systematic review of the literature addressing rates and predictors of pacemaker dependency in patients requiring permanent pacemaker implantation after cardiac surgery. Using a comprehensive search of the Medline, Web of Science and EMBASE databases, studies were selected for review based on predetermined inclusion and exclusion criteria. A total of 8 studies addressing the endpoint of pacemaker-dependency were identified, while 3 studies were found that addressed the recovery of atrioventricular (AV) conduction endpoint. There were 10 unique studies with a total of 780 patients. Mean follow-up ranged from 6-72 months. Pacemaker dependency rates ranged from 32%-91% and recovery of AV conduction ranged from 16%-42%. There was significant heterogeneity with respect to the definition of pacemaker dependency. Several patient and procedure-specific variables were found to be independently associated with pacemaker dependency, but these were not consistent between studies. Pacemaker dependency following cardiac surgery occurs with variable frequency. While individual studies have identified various perioperative risk factors for pacemaker dependency and non-resolution of AV conduction disease, results have been inconsistent. Well-conducted studies using a uniform definition of pacemaker dependency might identify patients who will benefit most from early permanent pacemaker implantation after cardiac surgery.

Kinetic study of time-dependent fixation of U"V"I on biochar

International Nuclear Information System (INIS)

Ashry, A.; Bailey, E.H.; Chenery, S.R.N.; Young, S.D.

2016-01-01

Biochar, a by-product from the production of biofuel and syngas by gasification, was tested as a material for adsorption and fixation of U"V"I from aqueous solutions. A batch experiment was conducted to study the factors that influence the adsorption and time-dependent fixation on biochar at 20 °C, including pH, initial concentration of U"V"I and contact time. Uranium (U"V"I) adsorption was highly dependent on pH but adsorption on biochar was high over a wide range of pH values, from 4.5 to 9.0, and adsorption strength was time-dependent over several days. The experimental data for pH > 7 were most effectively modelled using a Freundlich adsorption isotherm coupled to a reversible first order kinetic equation to describe the time-dependent fixation of U"V"I within the biochar structure. Desorption experiments showed that U"V"I was only sparingly desorbable from the biochar with time and isotopic dilution with "2"3"3U"V"I confirmed the low, or time-dependent, lability of adsorbed "2"3"8U"V"I. Below pH 7 the adsorption isotherm trend suggested precipitation, rather than true adsorption, may occur. However, across all pH values (4.5-9) measured saturation indices suggested precipitation was possible: autunite below pH 6.5 and either swartzite, liebigite or bayleyite above pH 6.5.

Finite-range-scaling analysis of metastability in an Ising model with long-range interactions

International Nuclear Information System (INIS)

Gorman, B.M.; Rikvold, P.A.; Novotny, M.A.

1994-01-01

We apply both a scalar field theory and a recently developed transfer-matrix method to study the stationary properties of metastability in a two-state model with weak, long-range interactions: the Nx∞ quasi-one-dimensional Ising model. Using the field theory, we find the analytic continuation f of the free energy across the first-order transition, assuming that the system escapes the metastable state by the nucleation of noninteracting droplets. We find that corrections to the field dependence are substantial, and, by solving the Euler-Lagrange equation for the model numerically, we have verified the form of the free-energy cost of nucleation, including the first correction. In the transfer-matrix method, we associate with the subdominant eigenvectors of the transfer matrix a complex-valued ''constrained'' free-energy density f α computed directly from the matrix. For the eigenvector with an associated magnetization most strongly opposed to the applied magnetic field, f α exhibits finite-range scaling behavior in agreement with f over a wide range of temperatures and fields, extending nearly to the classical spinodal. Some implications of these results for numerical studies of metastability are discussed

A study of the electromagnetic shielding mechanisms in the GHz frequency range of graphene based composite layers

Energy Technology Data Exchange (ETDEWEB)

Drakakis, E. [Electrical Engineering Department, School of Engineering, Technological Educational Institute of Crete, Heraklion (Greece); Kymakis, E. [Electrical Engineering Department, School of Engineering, Technological Educational Institute of Crete, Heraklion (Greece); Center of Materials Technology and Photonics, School of Engineering, Technological Educational Institute of Crete, Heraklion (Greece); Tzagkarakis, G.; Louloudakis, D.; Katharakis, M. [Center of Materials Technology and Photonics, School of Engineering, Technological Educational Institute of Crete, Heraklion (Greece); Kenanakis, G. [Institute of Electronic Structure & Laser (IESL), Foundation for Research and Technology (FORTH) Hellas, Heraklion (Greece); Suchea, M.; Tudose, V. [Center of Materials Technology and Photonics, School of Engineering, Technological Educational Institute of Crete, Heraklion (Greece); Chemistry Faculty, “Al.I.Cuza” University of Iasi, Iasi (Romania); Koudoumas, E., E-mail: koudoumas@staff.teicrete.gr [Electrical Engineering Department, School of Engineering, Technological Educational Institute of Crete, Heraklion (Greece); Center of Materials Technology and Photonics, School of Engineering, Technological Educational Institute of Crete, Heraklion (Greece)

2017-03-15

Highlights: • Optimum paint contents should be chosen so that homogeneous and uniform nanocomposite layers exist exhibiting effective electromagnetic shielding. • The electromagnetic shielding in the frequency range studied comes mainly from absorption and increases with frequency. • Reflection reduces with increasing frequency, the decrease rate being smaller than that of the increase in absorption. • The shielding efficiency depends on both conductivity and thickness, the first dependence being more pronounced. - Abstract: We report on the mechanisms of the electromagnetic interference shielding effect of graphene based paint like composite layers. In particular, we studied the absorption and reflection of electromagnetic radiation in the 4–20 GHz frequency of various dispersions employing different amounts of graphene nanoplatelets, polyaniline, and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate), special attention given on the relative contribution of each process in the shielding effect. Moreover, the influence of the composition, the thickness and the conductivity of the composite layers on the electromagnetic shielding was also examined.

A study of the electromagnetic shielding mechanisms in the GHz frequency range of graphene based composite layers

International Nuclear Information System (INIS)

Drakakis, E.; Kymakis, E.; Tzagkarakis, G.; Louloudakis, D.; Katharakis, M.; Kenanakis, G.; Suchea, M.; Tudose, V.; Koudoumas, E.

2017-01-01

Highlights: • Optimum paint contents should be chosen so that homogeneous and uniform nanocomposite layers exist exhibiting effective electromagnetic shielding. • The electromagnetic shielding in the frequency range studied comes mainly from absorption and increases with frequency. • Reflection reduces with increasing frequency, the decrease rate being smaller than that of the increase in absorption. • The shielding efficiency depends on both conductivity and thickness, the first dependence being more pronounced. - Abstract: We report on the mechanisms of the electromagnetic interference shielding effect of graphene based paint like composite layers. In particular, we studied the absorption and reflection of electromagnetic radiation in the 4–20 GHz frequency of various dispersions employing different amounts of graphene nanoplatelets, polyaniline, and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate), special attention given on the relative contribution of each process in the shielding effect. Moreover, the influence of the composition, the thickness and the conductivity of the composite layers on the electromagnetic shielding was also examined.

Dependability investigation of wireless short range embedded systems: hardware platform oriented approach

NARCIS (Netherlands)

Senouci, B.; Kerkhoff, Hans G.; Annema, Anne J.; Bentum, Marinus Jan

2015-01-01

A new direction in short-range wireless applications has appeared in the form of high-speed data communication devices for distances of hundreds meters. Behind these embedded applications, a complex heterogeneous architecture is built. Moreover, these short range communications are introduced into

Evolution of short range order in Ar: Liquid to glass and solid transitions-A computational study

Science.gov (United States)

Shor, Stanislav; Yahel, Eyal; Makov, Guy

2018-04-01

The evolution of the short range order (SRO) as a function of temperature in a Lennard-Jones model liquid with Ar parameters was determined and juxtaposed with thermodynamic and kinetic properties obtained as the liquid was cooled (heated) and transformed between crystalline solid or glassy states and an undercooled liquid. The Lennard-Jones system was studied by non-equilibrium molecular dynamics simulations of large supercells (approximately 20000 atoms) rapidly cooled or heated at selected quenching rates and at constant pressure. The liquid to solid transition was identified by discontinuities in the atomic volume and molar enthalpy; the glass transition temperature range was identified from the temperature dependence of the self-diffusion. The SRO was studied within the quasi-crystalline model (QCM) framework and compared with the Steinhardt bond order parameters. Within the QCM it was found that the SRO evolves from a bcc-like order in the liquid through a bct-like short range order (c/a=1.2) in the supercooled liquid which persists into the glass and finally to a fcc-like ordering in the crystalline solid. The variation of the SRO that results from the QCM compares well with that obtained with Steinhardt's bond order parameters. The hypothesis of icosahedral order in liquids and glasses is not supported by our results.

The Study of early maladaptive Schemas in Men Dependent on Drugs and those Not Dependent

Directory of Open Access Journals (Sweden)

MR Firoozi

2015-11-01

Full Text Available Introduction and Objectives of the Study Dependence on drugs is a prevalent problem throughout the world, in general and in Iran, in particular. Such a phenomenon is associated with numerous negative consequences. Given the changes in the consumption patterns in different countries, especially in Iran, and the abuse of drugs, identifying the factors which may pave the way for drug abuse is absolutely essential, which can be taken into account in setting the objectives of therapy programs. Cognizant of this, the present study has sought to study early maladaptive schemas in men dependent on drugs and those that are not. Materials and Method: The research design adopted in the present study was causal-comparative. The populaiton of interest was all the men dependent on drugs in the city of Yasouj, who had presented to recovery centers affiliated to welfare organization and Yasouj University of Medical Sciences in the year 2014 and were undergoing treatment. Using multi-stage cluster sampling, initially out of 23 centers for recovery programs, four centers were randomly chosen. Following that, out of each center, 20 and in total, 80 clients were chosen as the sample through convenience sampling. In addition, 80 men not dependent on drugs were chosen through matching with the sample dependent on drugs in terms of age, gender and locality. For the purpsoe of measuing early maladaptive schemas, we made use of the short version of Young’s early maladaptive Schemas Questionnaire. In order to determine the prevalent schemas in men dependent on drugs and those not dependent and the difference between the two groups, use was made of independent-sample t-test and effect size (d. Findings: The findings suggest that mean values of those dependent on drugs in all the schemas in quesiton were significantly higher than those of men not dependent. Although the difference in effect size of all schemas fell in the domain of the large effect, the largest

Is there a relationship between Internet dependence and eating disorders? A comparison study of Internet dependents and non-Internet dependents.

Science.gov (United States)

Tao, Z L; Liu, Y

2009-01-01

Several studies have examined the underlying psychopathology in overuse of the Internet, including depression, social anxiety, and substance dependence. A relationship between these psychological disorders appears to exist. No links have been established between Internet dependence and eating disorders. Fifty-four Internet dependents were compared with a control group concerning symptomatic aspects of eating disorders and psychological characteristics related to eating disorders. They all belonged to 1199 respondents of Chinese secondary school and college students between the ages of 12 and 25 years old. A Mann-Whitney U-test was used to determine the difference between Internet dependent groups and non-Internet dependent groups concerning Eating Attitudes Test and Eating Disorder Inventory scores. Females and male Internet dependents rated themselves with significantly higher symptomatic aspects of eating disorders than control groups. Female and male Internet dependents showed significantly higher psychological characteristics related to eating disorders than control groups. A relationship between Internet dependence and eating disorders appears to exist.

Experimental study of shear rate dependence in perpetually sheared granular matter

Directory of Open Access Journals (Sweden)

Liu Sophie Yang

2017-01-01

Full Text Available We study the shear behaviour of various granular materials by conducting novel perpetual simple shear experiments over four orders of magnitude of relatively low shear rates. The newly developed experimental apparatus employed is called “3D Stadium Shear Device” which is an extended version of the 2D Stadium Shear Device [1]. This device is able to provide a non-radial dependent perpetual shear flow and a nearly linear velocity profile between two oppositely moving shear walls. Using this device, we are able to test a large variety of granular materials. Here, we demonstrate the applicability of the device on glass beads (diameter 1 mm, 3 mm, and 14 mm and rice. We particularly focus on studying these materials at very low inertial number I ranging from 10−6 to 10−2. We find that, within this range of I, the friction coefficient μ of glass beads has no shear rate dependence. A particularly appealing observation comes from testing rice, where the attainment of critical state develops under much longer duration than in other materials. Initially during shear we find a value of μ similar to that found for glass beads, but with time this value decreases gradually towards the asymptotic critical state value. The reason, we believe, lies in the fact that rice grains are strongly elongated; hence the time to achieve the stable μ is primarily controlled by the time for particles to align themselves with respect to the shear walls. Furthermore, the initial packing conditions of samples also plays a role in the evolution of μ when the shear strain is small, but that impact will eventually be erased after sufficient shear strain.

Nonlocality and short-range wetting phenomena.

Science.gov (United States)

Parry, A O; Romero-Enrique, J M; Lazarides, A

2004-08-20

We propose a nonlocal interfacial model for 3D short-range wetting at planar and nonplanar walls. The model is characterized by a binding-potential functional depending only on the bulk Ornstein-Zernike correlation function, which arises from different classes of tubelike fluctuations that connect the interface and the substrate. The theory provides a physical explanation for the origin of the effective position-dependent stiffness and binding potential in approximate local theories and also obeys the necessary classical wedge covariance relationship between wetting and wedge filling. Renormalization group and computer simulation studies reveal the strong nonperturbative influence of nonlocality at critical wetting, throwing light on long-standing theoretical problems regarding the order of the phase transition.

Nonlocality and Short-Range Wetting Phenomena

Science.gov (United States)

Parry, A. O.; Romero-Enrique, J. M.; Lazarides, A.

2004-08-01

We propose a nonlocal interfacial model for 3D short-range wetting at planar and nonplanar walls. The model is characterized by a binding-potential functional depending only on the bulk Ornstein-Zernike correlation function, which arises from different classes of tubelike fluctuations that connect the interface and the substrate. The theory provides a physical explanation for the origin of the effective position-dependent stiffness and binding potential in approximate local theories and also obeys the necessary classical wedge covariance relationship between wetting and wedge filling. Renormalization group and computer simulation studies reveal the strong nonperturbative influence of nonlocality at critical wetting, throwing light on long-standing theoretical problems regarding the order of the phase transition.

Carbon dots with strong excitation-dependent fluorescence changes towards pH. Application as nanosensors for a broad range of pH

Energy Technology Data Exchange (ETDEWEB)

Barati, Ali [Faculty of Chemistry, Institute for Advanced Studies in Basic Sciences, Zanjan (Iran, Islamic Republic of); Department of Chemistry, Razi University, Kermanshah (Iran, Islamic Republic of); Shamsipur, Mojtaba, E-mail: mshamsipur@yahoo.com [Department of Chemistry, Razi University, Kermanshah (Iran, Islamic Republic of); Abdollahi, Hamid, E-mail: abd@iasbs.ac.ir [Faculty of Chemistry, Institute for Advanced Studies in Basic Sciences, Zanjan (Iran, Islamic Republic of)

2016-08-10

In this study, preparation of novel pH-sensitive N-doped carbon dots (NCDs) using glucose and urea is reported. The prepared NCDs present strong excitation-dependent fluorescence changes towards the pH that is a new behavior from these nanomaterials. By taking advantage of this unique behavior, two separated ratiometric pH sensors using emission spectra of the NCDs for both acidic (pH 2.0 to 8.0) and basic (pH 7.0 to 14.0) ranges of pH are constructed. Additionally, by considering the entire Excitation–Emission Matrix (EEM) of NCDs as analytical signal and using a suitable multivariate calibration method, a broad range of pH from 2.0 to 14.0 was well calibrated. The multivariate calibration method was independent from the concentration of NCDs and resulted in a very low average prediction error of 0.067 pH units. No changes in the predicted pH under UV irradiation (for 3 h) and at high ionic strength (up to 2 M NaCl) indicated the high stability of this pH nanosensor. The practicality of this pH nanosensor for pH determination in real water samples was validated with good accuracy and repeatability. - Highlights: • Novel pH-sensitive carbon dots with strong FL changes towards pH are reported. • Ratiometric FL pH-sensors for both acidic and basic ranges of pH are constructed. • Multivariate calibration methods were used to calibrate a broad range of pH. • Using EEM of carbon dots and ANN, pH from 2.0 to 14.0 was well calibrated. • The pH prediction is stable even at high ionic strength up to 2 M NaCl.

Carbon dots with strong excitation-dependent fluorescence changes towards pH. Application as nanosensors for a broad range of pH

International Nuclear Information System (INIS)

Barati, Ali; Shamsipur, Mojtaba; Abdollahi, Hamid

2016-01-01

In this study, preparation of novel pH-sensitive N-doped carbon dots (NCDs) using glucose and urea is reported. The prepared NCDs present strong excitation-dependent fluorescence changes towards the pH that is a new behavior from these nanomaterials. By taking advantage of this unique behavior, two separated ratiometric pH sensors using emission spectra of the NCDs for both acidic (pH 2.0 to 8.0) and basic (pH 7.0 to 14.0) ranges of pH are constructed. Additionally, by considering the entire Excitation–Emission Matrix (EEM) of NCDs as analytical signal and using a suitable multivariate calibration method, a broad range of pH from 2.0 to 14.0 was well calibrated. The multivariate calibration method was independent from the concentration of NCDs and resulted in a very low average prediction error of 0.067 pH units. No changes in the predicted pH under UV irradiation (for 3 h) and at high ionic strength (up to 2 M NaCl) indicated the high stability of this pH nanosensor. The practicality of this pH nanosensor for pH determination in real water samples was validated with good accuracy and repeatability. - Highlights: • Novel pH-sensitive carbon dots with strong FL changes towards pH are reported. • Ratiometric FL pH-sensors for both acidic and basic ranges of pH are constructed. • Multivariate calibration methods were used to calibrate a broad range of pH. • Using EEM of carbon dots and ANN, pH from 2.0 to 14.0 was well calibrated. • The pH prediction is stable even at high ionic strength up to 2 M NaCl.

Persistent cannabis dependence and alcohol dependence represent risks for midlife economic and social problems: A longitudinal cohort study

Science.gov (United States)

Cerdá, Magdalena; Moffitt, Terrie E.; Meier, Madeline H.; Harrington, HonaLee; Houts, Renate; Ramrakha, Sandhya; Hogan, Sean; Poulton, Richie; Caspi, Avshalom

2016-01-01

With the increasing legalization of cannabis, understanding the consequences of cannabis use is particularly timely. We examined the association between cannabis use and dependence, prospectively assessed between ages 18–38, and economic and social problems at age 38. We studied participants in the Dunedin Longitudinal Study, a cohort (n=1,037) followed from birth to age 38. Study members with regular cannabis use and persistent dependence experienced downward socioeconomic mobility, more financial difficulties, workplace problems, and relationship conflict in early midlife. Cannabis dependence was not linked to traffic-related convictions. Associations were not explained by socioeconomic adversity, childhood psychopathology, achievement orientation, or family structure; cannabis-related criminal convictions; early onset of cannabis dependence; or comorbid substance dependence. Cannabis dependence was associated with more financial difficulties than alcohol dependence; no difference was found in risks for other economic or social problems. Cannabis dependence is not associated with fewer harmful economic and social problems than alcohol dependence. PMID:28008372

Predictors of patient dependence in mild-to-moderate Alzheimer's disease.

Science.gov (United States)

Benke, Thomas; Sanin, Günter; Lechner, Anita; Dal-Bianco, Peter; Ransmayr, Gerhard; Uranüs, Margarete; Marksteiner, Josef; Gaudig, Maren; Schmidt, Reinhold

2015-01-01

Patient dependence has rarely been studied in mild-to-moderate Alzheimer's disease (AD). To identify factors which predict patient dependence in mild-to-moderate AD. We studied 398 non-institutionalized AD patients (234 females) of the ongoing Prospective Registry on Dementia (PRODEM) in Austria. The Dependence Scale (DS) was used to assess patient dependence. Patient assessment comprised functional abilities, neuropsychiatric symptoms and cognitive functions. A multiple linear regression analysis was performed to identify predictors of patient dependence. AD patients were mildly-to-moderately impaired (mean scores and SDs were: CDR 0.84 ± 0.43; DAD 74.4 ± 23.3, MMSE = 22.5 ± 3.6). Psychopathology and caregiver burden were in the low range (mean NPI score 13.2, range 0 to 98; mean ZBI score 18, range 0-64). Seventy five percent of patients were classified as having a mild level of patient dependence (DS sum score 0 to 6). Patient dependence correlated significantly and positively with age, functional measures, psychopathology and depression, disease duration, and caregiver burden. Significant negative, but low correlations were found between patient dependence, cognitive variables, and global cognition. Activities of daily living, patient age, and disease severity accounted for 63% of variance in patient dependence, whereas cognitive variables accounted for only 11%. Dependence in this cohort was mainly related to age and functional impairment, and less so to cognitive and neuropsychiatric variables. This differs from studies investigating patients in more advanced disease stages which found abnormal behavior and impairments of cognition as main predictors of patient dependence.

The continual reassessment method: comparison of Bayesian stopping rules for dose-ranging studies.

Science.gov (United States)

Zohar, S; Chevret, S

2001-10-15

The continual reassessment method (CRM) provides a Bayesian estimation of the maximum tolerated dose (MTD) in phase I clinical trials and is also used to estimate the minimal efficacy dose (MED) in phase II clinical trials. In this paper we propose Bayesian stopping rules for the CRM, based on either posterior or predictive probability distributions that can be applied sequentially during the trial. These rules aim at early detection of either the mis-choice of dose range or a prefixed gain in the point estimate or accuracy of estimated probability of response associated with the MTD (or MED). They were compared through a simulation study under six situations that could represent the underlying unknown dose-response (either toxicity or failure) relationship, in terms of sample size, probability of correct selection and bias of the response probability associated to the MTD (or MED). Our results show that the stopping rules act correctly, with early stopping by using the two first rules based on the posterior distribution when the actual underlying dose-response relationship is far from that initially supposed, while the rules based on predictive gain functions provide a discontinuation of inclusions whatever the actual dose-response curve after 20 patients on average, that is, depending mostly on the accumulated data. The stopping rules were then applied to a data set from a dose-ranging phase II clinical trial aiming at estimating the MED dose of midazolam in the sedation of infants during cardiac catheterization. All these findings suggest the early use of the two first rules to detect a mis-choice of dose range, while they confirm the requirement of including at least 20 patients at the same dose to reach an accurate estimate of MTD (MED). A two-stage design is under study. Copyright 2001 John Wiley & Sons, Ltd.

Methods for studying short-range order in solid binary solutions

International Nuclear Information System (INIS)

Beranger, Gerard

1969-12-01

The short range order definition and its characteristic parameters are first recalled. The different methods to study the short range order are then examined: X ray diffusion, electrical resistivity, specific heat and thermoelectric power, neutron diffraction, electron spin resonance, study of thermodynamic and mechanical properties. The theory of the X ray diffraction effects due to short range order and the subsequent experimental method are emphasized. The principal results obtained from binary Systems, by the different experimental techniques, are reported and briefly discussed. The Au-Cu, Li-Mg, Au-Ni and Cu-Zn Systems are moreover described. (author) [fr

Age- and size-related reference ranges: a case study of spirometry through childhood and adulthood.

Science.gov (United States)

Cole, T J; Stanojevic, S; Stocks, J; Coates, A L; Hankinson, J L; Wade, A M

2009-02-28

Age-related reference ranges are useful for assessing growth in children. The LMS method is a popular technique for constructing growth charts that model the age-changing distribution of the measurement in terms of the median, coefficient of variation and skewness. Here the methodology is extended to references that depend on body size as well as age, by exploiting the flexibility of the generalised additive models for location, scale and shape (GAMLSS) technique. GAMLSS offers general linear predictors for each moment parameter and a choice of error distributions, which can handle kurtosis as well as skewness. A key question with such references is the nature of the age-size adjustment, additive or multiplicative, which is explored by comparing the identity link and log link for the median predictor.There are several measurements whose reference ranges depend on both body size and age. As an example, models are developed here for the first four moments of the lung function variables forced expiratory volume in 1 s (FEV(1)), forced vital capacity (FVC) and FEV(1)/FVC in terms of height and age, in a data set of 3598 children and adults aged 4 to 80 years. The results show a strong multiplicative association between spirometry, height and age, with a large and nonlinear age effect across the age range. Variability also depends nonlinearly on age and to a lesser extent on height. FEV(1) and FVC are close to normally distributed, while FEV(1)/FVC is appreciably skew to the left. GAMLSS is a powerful technique for the construction of such references, which should be useful in clinical medicine. Copyright (c) 2008 John Wiley & Sons, Ltd.

Probing the role of long-range interactions in the dynamics of a long-range Kitaev chain

Science.gov (United States)

Dutta, Anirban; Dutta, Amit

2017-09-01

We study the role of long-range interactions (more precisely, the long-range superconducting gap term) on the nonequilibrium dynamics considering a long-range p -wave superconducting chain in which the superconducting term decays with distance between two sites in a power-law fashion characterized by an exponent α . We show that the Kibble-Zurek scaling exponent, dictating the power-law decay of the defect density in the final state reached following a slow (in comparison to the time scale associated with the minimum gap in the spectrum of the Hamiltonian) quenching of the chemical potential μ across a quantum critical point, depends nontrivially on the exponent α as long as α 2 , we find that the exponent saturates to the corresponding well-known value of 1 /2 expected for the short-range model. Furthermore, studying the dynamical quantum phase transitions manifested in the nonanalyticities in the rate function of the return possibility I (t ) in subsequent temporal evolution following a sudden change in μ , we show the existence of a new region; in this region, we find three instants of cusp singularities in I (t ) associated with a single sector of Fisher zeros. Notably, the width of this region shrinks as α increases and vanishes in the limit α →2 , indicating that this special region is an artifact of the long-range nature of the Hamiltonian.

Metabolic studies in unaffected co-twins of non-insulin-dependent diabetics.

OpenAIRE

Barnett, A H; Spiliopoulos, A J; Pyke, D A; Stubbs, W A; Burrin, J; Alberti, K G

1981-01-01

Forty-eight out of 53 non-insulin-dependent diabetic identical twin pairs were concordant for diabetes. In the five discordant pairs the diabetic twin had only recently been diagnosed. Oral glucose tolerance tests were carried out on the unaffected twins of the five pairs and on matched controls. Fasting concentrations of blood glucose (5.5 +/- 0.6 v 3.7 +/- 0.3 mmol/l; 99.1 +/- 10.8 v 66.6 +/- 5.4 mg/100 ml), haemoglobin A1 (mean 9.1%, range 8.8-9.2% v mean 7.9%, range 7.4-8.4%), lactate, al...

Size of pancreas in non-insulin-dependent diabetes mellitus: a study based on CT

International Nuclear Information System (INIS)

Shin, Ju Won; Yoon, Soon Min; Yoon, Mi Jin; Song, Moon Gab; Kim, Yoon Suk; Yoon, Young Kyu; Jun, Se June

1997-01-01

To evaluate changes of pancreatic size with aging in control subjects and in non-insulin- dependent diabetic patients. Two groups of non-insulin-dependent diabetic patients were examined; one had been treated with an oral hypoglycemic agent(n=59), and the other with insulin(n=56). The CT findings of 175 patients without clinical evidence of pancreatic disease were included as a normal control. In control subjects, pancreatic size and age correlated. The pancreas was smaller in non-insulin-dependent diabetics than in control subjects and smaller in insulin- treated non-insulin-dependent diabetics than in non-insulin treated patients. The pancreas was smaller in non-insulin-dependent diabetic patients than in control subjects within the same age range

A dynamic approach to dependability studies

International Nuclear Information System (INIS)

Labeau, P.E.

2008-01-01

Dependability studies have now become an important part of the performance management of industrial plants. These last decades, several methods have been proposed and widely used for the analysis of systems of components subject to degradation and failure. These methods are based either on Boolean representations (for example, event trees/fault trees), or on discrete-state models (Markovian reliability, Petri nets, Bayesian networks...). However, the underlying, inherently continuous, physical processes have scarcely been accounted for, at least in an integrated fashion, in dependability studies. This paper first describes, through simple cases, the limitations of discrete approaches and the need of hybrid, discrete-continuous methods. It then summarizes the main concepts of dynamic reliability. Finally, some possible application domains are presented, as well as challenges that still need to be tackled to favour the diffusion of this approach among industrial circles. (author)

Evaluation of Nine Consensus Indices in Delphi Foresight Research and Their Dependency on Delphi Survey Characteristics: A Simulation Study and Debate on Delphi Design and Interpretation.

Science.gov (United States)

Birko, Stanislav; Dove, Edward S; Özdemir, Vural

2015-01-01

The extent of consensus (or the lack thereof) among experts in emerging fields of innovation can serve as antecedents of scientific, societal, investor and stakeholder synergy or conflict. Naturally, how we measure consensus is of great importance to science and technology strategic foresight. The Delphi methodology is a widely used anonymous survey technique to evaluate consensus among a panel of experts. Surprisingly, there is little guidance on how indices of consensus can be influenced by parameters of the Delphi survey itself. We simulated a classic three-round Delphi survey building on the concept of clustered consensus/dissensus. We evaluated three study characteristics that are pertinent for design of Delphi foresight research: (1) the number of survey questions, (2) the sample size, and (3) the extent to which experts conform to group opinion (the Group Conformity Index) in a Delphi study. Their impacts on the following nine Delphi consensus indices were then examined in 1000 simulations: Clustered Mode, Clustered Pairwise Agreement, Conger's Kappa, De Moivre index, Extremities Version of the Clustered Pairwise Agreement, Fleiss' Kappa, Mode, the Interquartile Range and Pairwise Agreement. The dependency of a consensus index on the Delphi survey characteristics was expressed from 0.000 (no dependency) to 1.000 (full dependency). The number of questions (range: 6 to 40) in a survey did not have a notable impact whereby the dependency values remained below 0.030. The variation in sample size (range: 6 to 50) displayed the top three impacts for the Interquartile Range, the Clustered Mode and the Mode (dependency = 0.396, 0.130, 0.116, respectively). The Group Conformity Index, a construct akin to measuring stubbornness/flexibility of experts' opinions, greatly impacted all nine Delphi consensus indices (dependency = 0.200 to 0.504), except the Extremity CPWA and the Interquartile Range that were impacted only beyond the first decimal point (dependency = 0

Study of thin films and V2O3 monocrystals in the range of phase transformations by the method of the surface acoustic waves

International Nuclear Information System (INIS)

Boborykina, E.N.; Nikitin, S.E.; Chudnovskij, F.A.

1995-01-01

A study was made on acoustic-electron interaction in films and V 2 O 3 monocrystals in 80-450 K range, including the region of metal-antiferromagnetic insulator phase transformation (PTM↔AFI) and the region of high-temperature anomalies. Temperature dependences of absorption and change of surface acoustic wave (SAW) velocity were measured. The maximum on temperature dependences of absorption and change of SAW velocity in the region of PTM↔AFI was revealed. 9 refs.; 4 figs

Observed Orbit Effects during Long Range Beam-Beam Studies

CERN Document Server

Alemany, R; Buffat, X; Calaga, R; Fitterer, M; Giachino, R; Hemelsoet, GH; Herr, W; Papotti, G; Pieloni, T; Poyer, M; Schaumann, M; Trad, G; Wollmann, D

2012-01-01

Possible limitations due to long range beam-beam effects at the LHC have been studied and are presented in this note. With a larger number of bunches and collisions in all interaction points, the crossing angles were reduced to enhance long range beam-beam effects. The analysis of the effects on the dynamic aperture and losses are documented in [1]. This note concentrates on the bunch-by-bunch orbit effects observed during the experiment.

Long-range Rocky Flats utilization study

International Nuclear Information System (INIS)

1983-02-01

The purpose of this Study was to provide information concerning the Rocky Flats Plant and its operations that will be useful to the Nation's decision-makers in determining the long-range future of the Plant. This Study was conducted under the premise that national defense policy must be supported and, accordingly, the capabilities at Rocky Flats must be maintained there or at some other location(s). The Study, therefore, makes no attempt to speculate on how possible future changes in national defense policy might affect decisions regarding the utilization of Rocky Flats. Factors pertinent to decisions regarding Rocky Flats, which are included in the Study, are: physical condition of the Plant and its vulnerabilities to natural phenomena; risks associated with plutonium to Plant workers and the public posed by postulated natural phenomena and operational accidents; identification of alternative actions regarding the future use of the Rocky Flats Plant with associated costs and time scales; local socioeconomic impacts if Rocky Flats operations were relocated; and potential for other uses if Rocky Flats facilities were vacated. The results of the tasks performed in support of this Study are summarized in the context of these five factors

Infrared cross-sections and integrated band intensities of propylene: Temperature-dependent studies

KAUST Repository

Es-sebbar, Et-touhami

2014-01-01

Propylene, a by-product of biomass burning, thermal cracking of hydrocarbons and incomplete combustion of fossil fuels, is a ubiquitous molecule found in the environment and atmosphere. Accurate infrared (IR) cross-sections and integrated band intensities of propylene are essential for quantitative measurements and atmospheric modeling. We measured absolute IR cross-sections of propylene using Fourier Transform Infrared (FTIR) Spectroscopy over the wavenumber range of 400-6500cm-1 and at gas temperatures between 296 and 460K. We recorded these spectra at spectral resolutions ranging from 0.08 to 0.5cm-1 and measured the integrated band intensities for a number of vibrational bands in certain spectral regions. We then compared the integrated band intensities measured at room temperature with values derived from the National Institute of Standards and Technology (NIST) and the Pacific Northwest National Laboratory (PNNL) databases. Our results agreed well with the results reported in the two databases with a maximum deviation of about 4%. The peak cross-sections for the primary bands decreased by about 20-54% when the temperature increased from 296 to 460K. Moreover, we determined the integrated band intensities as a function of temperature for certain features in various spectral regions; we found no significant temperature dependence over the range of temperatures considered here. We also studied the effect of temperature on absorption cross-section using a Difference Frequency Generation (DFG) laser system. We compared the DFG results with those obtained from the FTIR study at certain wavenumbers over the 2850-2975cm-1 range and found a reasonable agreement with less than 10% discrepancy. © 2013 Elsevier Ltd.

Study of plastic deformation peculiarities in CdS single crystals within the temperature range of 25 to 300 deg C

International Nuclear Information System (INIS)

Bulatova, T.M.

1990-01-01

By the method of stress relaxation dependences of platic deformation rate on effective strain in CdS monocrystals for the temperatures of 25-300 deg C both in the darkness and in the light are obtained. In the range of the temperatures up to 150 deg C deformation activation energy is determined, which correlates with the value of point defect diffusion activation energy in the crystal. Anomalous temperature dependence of plastic deformation rate, i.e. its decrease with the temperature increase in the range of 150-300 deg C is detected

Analysis of dependent failures in the ORNL precursor study

International Nuclear Information System (INIS)

Ballard, G.M.

1985-01-01

The study of dependent failures (or common cause/mode failures) in the safety assessment of potentially hazardous plant is one of the significant areas of uncertainty in performing probabilistic safety studies. One major reason for this uncertainty is that data on dependent failures is apparently not readily available in sufficient quantity to assist in the development and validation of models. The incident reports that were compiled for the ORNL study on Precursors to Severe Core Damage Accidents (NUREG/CR-2497) provide an opportunity to look at the importance of dependent failures in the most significant incidents of recent reactor operations, to look at the success of probabilistic risk assessment (PRA) methods in accounting for the contribution of dependent failures, and to look at the dependent failure incidents with the aim of identifying the most significant problem areas. In this paper an analysis has been made of the incidents compiled in NUREG/CR-2497 and events involving multiple failures which were not independent have been identified. From this analysis it is clear that dependent failures are a very significant contributor to the precursor incidents. The method of enumeration of accident frequency used in NUREG-2497 can be shown to take account of dependent failures and this may be a significant factor contributing to the apparent difference between the precursor accident frequency and typical PRA frequencies

Transcript of the proceedings of the first Albuquerque informal range/energy workshop

International Nuclear Information System (INIS)

Brice, D.K.

1981-04-01

An informal workshop was held to discuss aspects of the calculation of range and energy deposition distributions which are of interest in ion implantation experiments. Topics covered include: problems encountered in using published range and energy deposition tabulations; some limitations in the solutions of range/energy transport equations; the effect of the scattering cross section on straggle; Monte Carlo calculations of ranges and straggling; damage studies in aluminum; simulation of heavy-ion irradiation of gold using MARLOWE; and MARLOWE calculations of range distribution parameters - dependence on input data and calculational model

Study on the effect of testing machine rigidity on strength and ductility temperature dependences obtained

International Nuclear Information System (INIS)

Krashchenko, V.P.; Statsenko, V.E.; Rudnitskij, N.P.

1984-01-01

Investigation procedures are described for rigidity of testing machines and mechanical properties of tantalum and nickel in the temperature range 293-1873K. Temperature dependences are presented for strength characteristics of the investigated materials obtained with the use of installations of different rigidity. Dependence analysis is carried out and recommendations are given as to the characteristics application

Physical and biological factors determining the effective proton range

International Nuclear Information System (INIS)

Grün, Rebecca; Friedrich, Thomas; Krämer, Michael; Scholz, Michael; Zink, Klemens; Durante, Marco; Engenhart-Cabillic, Rita

2013-01-01

Purpose: Proton radiotherapy is rapidly becoming a standard treatment option for cancer. However, even though experimental data show an increase of the relative biological effectiveness (RBE) with depth, particularly at the distal end of the treatment field, a generic RBE of 1.1 is currently used in proton radiotherapy. This discrepancy might affect the effective penetration depth of the proton beam and thus the dose to the surrounding tissue and organs at risk. The purpose of this study was thus to analyze the impact of a tissue and dose dependent RBE of protons on the effective range of the proton beam in comparison to the range based on a generic RBE of 1.1.Methods: Factors influencing the biologically effective proton range were systematically analyzed by means of treatment planning studies using the Local Effect Model (LEM IV) and the treatment planning software TRiP98. Special emphasis was put on the comparison of passive and active range modulation techniques.Results: Beam energy, tissue type, and dose level significantly affected the biological extension of the treatment field at the distal edge. Up to 4 mm increased penetration depth as compared to the depth based on a constant RBE of 1.1. The extension of the biologically effective range strongly depends on the initial proton energy used for the most distal layer of the field and correlates with the width of the distal penumbra. Thus, the range extension, in general, was more pronounced for passive as compared to active range modulation systems, whereas the maximum RBE was higher for active systems.Conclusions: The analysis showed that the physical characteristics of the proton beam in terms of the width of the distal penumbra have a great impact on the RBE gradient and thus also the biologically effective penetration depth of the beam

Study of beam-beam long range compensation with octupoles

CERN Document Server

AUTHOR|(CDS)2068329; Pieloni, Tatiana; Buffat, Xavier; Tambasco, Claudia

2017-01-01

Long range beam-beam effects are responsible for particle losses and define fundamental operational parameters of colliders (i.e. crossing angles, intensities, emittances, ${\\beta}$${^∗}$). In this study we propose octuple magnets as a possible scheme to efficiently compensate long-range beam-beam interactions with a global correction scheme. The impact and improvements on the dynamic aperture of colliding beams together with estimates of the luminosity potentials are dis- cussed for the HL-LHC upgrade and extrapolations made for the FCC project.

Improving PET Quantification of Small Animal [68Ga]DOTA-Labeled PET/CT Studies by Using a CT-Based Positron Range Correction.

Science.gov (United States)

Cal-Gonzalez, Jacobo; Vaquero, Juan José; Herraiz, Joaquín L; Pérez-Liva, Mailyn; Soto-Montenegro, María Luisa; Peña-Zalbidea, Santiago; Desco, Manuel; Udías, José Manuel

2018-01-19

Image quality of positron emission tomography (PET) tracers that emits high-energy positrons, such as Ga-68, Rb-82, or I-124, is significantly affected by positron range (PR) effects. PR effects are especially important in small animal PET studies, since they can limit spatial resolution and quantitative accuracy of the images. Since generators accessibility has made Ga-68 tracers wide available, the aim of this study is to show how the quantitative results of [ 68 Ga]DOTA-labeled PET/X-ray computed tomography (CT) imaging of neuroendocrine tumors in mice can be improved using positron range correction (PRC). Eighteen scans in 12 mice were evaluated, with three different models of tumors: PC12, AR42J, and meningiomas. In addition, three different [ 68 Ga]DOTA-labeled radiotracers were used to evaluate the PRC with different tracer distributions: [ 68 Ga]DOTANOC, [ 68 Ga]DOTATOC, and [ 68 Ga]DOTATATE. Two PRC methods were evaluated: a tissue-dependent (TD-PRC) and a tissue-dependent spatially-variant correction (TDSV-PRC). Taking a region in the liver as reference, the tissue-to-liver ratio values for tumor tissue (TLR tumor ), lung (TLR lung ), and necrotic areas within the tumors (TLR necrotic ) and their respective relative variations (ΔTLR) were evaluated. All TLR values in the PRC images were significantly different (p DOTA-labeled PET/CT imaging of mice with neuroendocrine tumors, hence demonstrating that these techniques could also ameliorate the deleterious effect of the positron range in clinical PET imaging.

Economic Viability Study of an On-Road Wireless Charging System with a Generic Driving Range Estimation Method

Directory of Open Access Journals (Sweden)

Aditya Shekhar

2016-01-01

Full Text Available The economic viability of on-road wireless charging of electric vehicles (EVs strongly depends on the choice of the inductive power transfer (IPT system configuration (static or dynamic charging, charging power level and the percentage of road coverage of dynamic charging. In this paper, a case study is carried out to determine the expected investment costs involved in installing the on-road charging infrastructure for an electric bus fleet. Firstly, a generic methodology is described to determine the driving range of any EV (including electric buses with any gross mass and frontal area. A dynamic power consumption model is developed for the EV, taking into account the rolling friction, acceleration, deceleration, aerodynamic drag, regenerative braking and Li-ion battery behavior. Based on the simulation results, the linear dependence of the battery state of charge (SoC on the distance traveled is proven. Further, the impact of different IPT system parameters on driving range is incorporated. Economic implications of a combination of different IPT system parameters are explored for achieving the required driving range of 400 km, and the cost optimized solution is presented for the case study of an electric bus fleet. It is shown that the choice of charging power level and road coverage are interrelated in the economic context. The economic viability of reducing the capacity of the on-board battery as a trade-off between higher transport efficiency and larger on-road charging infrastructure is presented. Finally, important considerations, like the number of average running buses, scheduled stoppage time and on-board battery size, that make on-road charging an attractive option are explored. The cost break-up of various system components of the on-road charging scheme is estimated, and the final project cost and parameters are summarized. The specific cost of the wireless on-road charging system is found to be more expensive than the conventional

Temperature-dependent vibrational spectroscopy to study order-disorder transitions in charge transfer complexes

Science.gov (United States)

Isaac, Rohan; Goetz, Katelyn P.; Roberts, Drew; Jurchescu, Oana D.; McNeil, L. E.

2018-02-01

Charge-transfer (CT) complexes are a promising class of materials for the semiconductor industry because of their versatile properties. This class of compounds shows a variety of phase transitions, which are of interest because of their potential impact on the electronic characteristics. Here temperature-dependent vibrational spectroscopy is used to study structural phase transitions in a set of organic CT complexes. Splitting and broadening of infrared-active phonons in the complex formed between pyrene and pyromellitic dianhydride (PMDA) confirm the structural transition is of the order-disorder type and complement previous x-ray diffraction (XRD) results. We show that this technique is a powerful tool to characterize transitions, and apply it to a range of binary CT complexes composed of polyaromatic hyrdocarbons (anthracene, perylene, phenanthrene, pyrene, and stilbene) and PMDA. We extend the understanding of transitions in perylene-PMDA and pyrene-PMDA, and show that there are no order-disorder transitions present in anthracene-PMDA, stilbene-PMDA and phenanthrene-PMDA in the temperature range investigated here.

Energy Dependence of Elliptic Flow over a Large Pseudorapidity Range in Au+Au Collisions at the BNL Relativistic Heavy Ion Collider

Science.gov (United States)

Back, B. B.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Betts, R. R.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Chai, Z.; Decowski, M. P.; García, E.; Gburek, T.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Hauer, M.; Heintzelman, G. A.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Hołyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; McLeod, D.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Seals, H.; Sedykh, I.; Skulski, W.; Smith, C. E.; Stankiewicz, M. A.; Steinberg, P.; Stephans, G. S.; Sukhanov, A.; Tang, J.-L.; Tonjes, M. B.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Vaurynovich, S. S.; Verdier, R.; Veres, G. I.; Wenger, E.; Wolfs, F. L.; Wosiek, B.; Woźniak, K.; Wuosmaa, A. H.; Wysłouch, B.

2005-04-01

This Letter describes the measurement of the energy dependence of elliptic flow for charged particles in Au+Au collisions using the PHOBOS detector at the Relativistic Heavy Ion Collider. Data taken at collision energies of √(sNN)=19.6, 62.4, 130, and 200 GeV are shown over a wide range in pseudorapidity. These results, when plotted as a function of η'=|η|-ybeam, scale with approximate linearity throughout η', implying no sharp changes in the dynamics of particle production as a function of pseudorapidity or increasing beam energy.

Front Range Forest Health Partnership Phase 1 feasibility study

Energy Technology Data Exchange (ETDEWEB)

Volkin, P

1998-09-01

The Front Range Forest Health Partnership is an alliance of individuals, citizen groups, federal, state, private, and nonprofit organizations that formed to promote forest health restoration and reduce fire risks on Colorado's Front Range. The partnership promotes selective thinning to restore forest health and supports economically feasible end uses for wood waste materials. The Phase I study was initiated to determine the environmental and economic feasibility of using wood wastes from forested and urban areas for the production of fuel-grade ethanol.

Physical and psychological nicotine dependence in Greeks: an epidemiological study.

Science.gov (United States)

Margaritis, Vasileios; Mamai-Homata, Eleni

2010-01-01

Smoking is the most widespread addictive behaviour in the world, as it causes physical and psychological dependence on nicotine. The objective of the present study was to discern the prevalence and the relative risks of nicotine dependence of adult people in Athens, Greece, as this country holds first place in cigarette consumption in the European Union. A random sample of 202 current smokers (82 men and 120 women) was drawn from residents aged v 18 years in Athens, the capital of Greece. A questionnaire on the physical (Fagerstrom Test of Nicotine Dependence) and psychological (American Psychiatric Association's diagnostic criteria of nicotine abuse) nicotine dependence was used. According to the results of the present study, 12.4% of the sample reported null physical nicotine dependence, and 31.7% had low, 25.7% had moderate and 30.2% had high nicotine dependence. Multiple logistic regression analysis revealed that younger people (aged 18 to 24 and 25 to 34, odds ratio [OR] = 0.047, P physical dependence. Women tended to be systematically less dependent than men (25% and 37.8% high dependence, respectively). Furthermore, 75.7% of the sample had psychological nicotine dependence. Binary logistic regression analysis and chi-square test revealed that younger people (18- to 24-year-olds, OR = 0.081, P dependence. In addition, women showed a higher percentage of withdrawal symptoms compared with men (80% and 68%, respectively). The results of the present study provided compelling evidence that physical and, in particular, psychological nicotine dependence of adult people in Athens, Greece, was significant, and this calls for a course of action that should be taken by public health policy-makers to reduce smoke consumption.

Low temperature resistivity studies of SmB6: Observation of two-dimensional variable-range hopping conductivity

Science.gov (United States)

Batkova, Marianna; Batko, Ivan; Gabáni, Slavomír; Gažo, Emil; Konovalova, Elena; Filippov, Vladimir

2018-05-01

We studied electrical resistance of a single-crystalline SmB6 sample with a focus on the region of the "low-temperature resistivity plateau". Our observations did not show any true saturation of the electrical resistance at temperatures below 3 K down to 70 mK. According to our findings, temperature dependence of the electrical conduction in a certain temperature interval above 70 mK can be decomposed into a temperature-independent term and a temperature-activated term that can be described by variable-range hopping formula for two-dimensional systems, exp [ -(T0 / T) 1 / 3 ]. Thus, our results indicate importance of hopping type of electrical transport in the near-surface region of SmB6.

Temperature dependence of plastic scintillators

Science.gov (United States)

Peralta, L.

2018-03-01

Plastic scintillator detectors have been studied as dosimeters, since they provide a cost-effective alternative to conventional ionization chambers. Several articles have reported undesired response dependencies on beam energy and temperature, which provides the motivation to determine appropriate correction factors. In this work, we studied the light yield temperature dependency of four plastic scintillators, BCF-10, BCF-60, BC-404, RP-200A and two clear fibers, BCF-98 and SK-80. Measurements were made using a 50 kVp X-ray beam to produce the scintillation and/or radioluminescence signal. The 0 to 40 °C temperature range was scanned for each scintillator, and temperature coefficients were obtained.

Normal range of facial asymmetry in spherical coordinates: a CBCT study

Energy Technology Data Exchange (ETDEWEB)

Yoon, Suk Ja [Dept. of Oral and Maxillofacial Radiology, School of Dentistry, Dental Science Research Institute, Chonnam National University, Gwangju (Korea, Republic of); Wang, Rui Feng [Research Laboratory Specialist Intermediate, Department of Biologic and Material Sciences, School of Dentistry, University of Michigan, Ann Arbor, MI (United States); Na, Hee Ja [Dept. ofDental Hygiene, Honam University, Gwangju (Korea, Republic of); Palomo, Juan Matin [Dept. of Orthodontics, School of Dental Medicine, Case Western Reserve University, Cleveland (United States)

2013-03-15

This study aimed to measure the bilateral differences of facial lines in spherical coordinates from faces within a normal range of asymmetry utilizing cone-beam computed tomography (CBCT). CBCT scans from 22 females with normal symmetric-looking faces (mean age 24 years and 8 months) were selected for the study. The average menton deviation was 1.01{+-}0.66 mm. The spherical coordinates, length, and midsagittal and coronal inclination angles of the ramal and mandibular lines were calculated from CBCT. The bilateral differences in the facial lines were determined. All of the study subjects had minimal bilateral differences of facial lines. The normal range of facial asymmetry of the ramal and mandibular lines was obtained in spherical coordinates. The normal range of facial asymmetry in the spherical coordinate system in this study should be useful as a reference for diagnosing facial asymmetry.

Lattice Parameter of Polycrystalline Diamond in the Low-Temperature Range

International Nuclear Information System (INIS)

Paszkowicz, W.; Piszora, P.; Lasocha, W.; Margiolaki, I.; Brunelli, M.; Fitch, A.

2010-01-01

The lattice parameter for polycrystalline diamond is determined as a function of temperature in the 4-300 K temperature range. In the range studied, the lattice parameter, expressed in angstrom units, of the studied sample increases according to the equation a = 3.566810(12) + 6.37(41) x 10 -14 T 4 (approximately, from 3.5668 to 3.5673 A). This increase is larger than that earlier reported for pure single crystals. The observed dependence and the resulting thermal expansion coefficient are discussed on the basis of literature data reported for diamond single crystals and polycrystals. (authors)

Recent results on short-range gravity experiment

International Nuclear Information System (INIS)

Hata, Maki; Akiyama, Takashi; Ikeda, Yuki; Kawamura, Hirokazu; Narita, Keigo; Ninomiya, Kazufumi; Ogawa, Naruya; Sato, Toshiaki; Seitaibashi, Etsuko; Sekiguchi, Yuta; Tsutsui, Ryosuke; Yazawa, Kazumasa; Murata, Jiro

2009-01-01

According to the ADD model, deviation from Newton's inverse square law is expected at below sub-millimeter scale. Present study is an experimental investigation of the Newton's gravitational law at a short range scale. We have developed an experimental setup using torsion balance bar, and succeeded to confirm the inverse square law at a centimeter scale. In addition, composition dependence of gravitational constant G is also tested at the centimeter scale, motivated to test the weak equivalence principle.

Reaction CH3 + OH studied over the 294-714 K temperature and 1-100 bar pressure ranges.

Science.gov (United States)

Sangwan, Manuvesh; Chesnokov, Evgeni N; Krasnoperov, Lev N

2012-08-30

Reaction of methyl radicals with hydroxyl radicals, CH(3) + OH → products (1) was studied using pulsed laser photolysis coupled to transient UV-vis absorption spectroscopy over the 294-714 K temperature and 1-100 bar pressure ranges (bath gas He). Methyl radicals were produced by photolysis of acetone at 193.3 nm. Hydroxyl radicals were generated in reaction of electronically excited oxygen atoms O((1)D), produced in the photolysis of N(2)O at 193.3 nm, with H(2)O. Temporal profiles of CH(3) were recorded via absorption at 216.4 nm using xenon arc lamp and a spectrograph; OH radicals were monitored via transient absorption of light from a dc discharge H(2)O/Ar low pressure resonance lamp at ca. 308 nm. The absolute intensity of the photolysis light inside the reactor was determined by an accurate in situ actinometry based on the ozone formation in the presence of molecular oxygen. The results of this study indicate that the rate constant of reaction 1 is pressure independent within the studied pressure and temperature ranges and has slight negative temperature dependence, k(1) = (1.20 ± 0.20) × 10(-10)(T/300)(-0.49) cm(3) molecule(-1) s(-1).

Interplay of long-range and short-range Coulomb interactions in an Anderson-Mott insulator

Science.gov (United States)

Baćani, Mirko; Novak, Mario; Orbanić, Filip; Prša, Krunoslav; Kokanović, Ivan; Babić, Dinko

2017-07-01

In this paper, we tackle the complexity of coexisting disorder and Coulomb electron-electron interactions (CEEIs) in solids by addressing a strongly disordered system with intricate CEEIs and a screening that changes both with charge carrier doping level Q and temperature T . We report on an experimental comparative study of the T dependencies of the electrical conductivity σ and magnetic susceptibility χ of polyaniline pellets doped with dodecylbenzenesulfonic acid over a wide range. This material is special within the class of doped polyaniline by exhibiting in the electronic transport a crossover between a low-T variable range hopping (VRH) and a high-T nearest-neighbor hopping (NNH) well below room temperature. Moreover, there is evidence of a soft Coulomb gap ΔC in the disorder band, which implies the existence of a long-range CEEI. Simultaneously, there is an onsite CEEI manifested as a Hubbard gap U and originating in the electronic structure of doped polyaniline, which consists of localized electron states with dynamically varying occupancy. Therefore, our samples represent an Anderson-Mott insulator in which long-range and short-range CEEIs coexist. The main result of the study is the presence of a crossover between low- and high-T regimes not only in σ (T ) but also in χ (T ) , the crossover temperature T* being essentially the same for both observables over the entire doping range. The relatively large electron localization length along the polymer chains results in U being small, between 12 and 20 meV for the high and low Q , respectively. Therefore, the thermal energy at T* is sufficiently large to lead to an effective closing of the Hubbard gap and the consequent appearance of NNH in the electronic transport within the disorder band. ΔC is considerably larger than U , decreasing from 190 to 30 meV as Q increases, and plays the role of an activation energy in the NNH.

Study of energetic dependence of LiF TLDs for photons

International Nuclear Information System (INIS)

Cavalieri, Tassio A.; Antunes, Paula C.G.; Paiva, Fabio; Branco, Isabela S.; Sena, Michelle K.S.; Siqueira, Paulo T.D.; Yoriyaz, Helio

2015-01-01

The LiF TLDs are widely used for photon dosimetry. However, in the most case the energetic dependence of these TLDs are not taken into account. This work is a preliminary study of energetic photon dependence in LiF TLD (TLD 700, enriched with 7 Li). For this study it was utilized a methodology already used in others works that seek understand the dependence energetic of TLD. It was utilized three different X-ray spectrum and a 137 Cs source; Beyond the calculus utilized in previous works, it was built the calibration curve for each spectrum to see the difference in dosimetry that the energetic dependence could cause. (author)

Study of energetic dependence of LiF TLDs for photons

Energy Technology Data Exchange (ETDEWEB)

Cavalieri, Tassio A.; Antunes, Paula C.G.; Paiva, Fabio; Branco, Isabela S.; Sena, Michelle K.S.; Siqueira, Paulo T.D.; Yoriyaz, Helio, E-mail: tcavalieri@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2015-07-01

The LiF TLDs are widely used for photon dosimetry. However, in the most case the energetic dependence of these TLDs are not taken into account. This work is a preliminary study of energetic photon dependence in LiF TLD (TLD 700, enriched with {sup 7}Li). For this study it was utilized a methodology already used in others works that seek understand the dependence energetic of TLD. It was utilized three different X-ray spectrum and a {sup 137}Cs source; Beyond the calculus utilized in previous works, it was built the calibration curve for each spectrum to see the difference in dosimetry that the energetic dependence could cause. (author)

Extended parametric gain range in photonic crystal fibers with strongly frequency-dependent field distributions.

Science.gov (United States)

Petersen, Sidsel R; Alkeskjold, Thomas T; Olausson, Christina B; Lægsgaard, Jesper

2014-08-15

The parametric gain range of a degenerate four-wave mixing process is determined in the undepleted pump regime. The gain range is considered with and without taking the mode field distributions of the four-wave mixing components into account. It is found that the mode field distributions have to be included to evaluate the parametric gain correctly in dispersion-tailored speciality fibers and that mode profile engineering can provide a way to increase the parametric gain range.

Optical Spectra of Hemoglobin Taken from Alcohol Dependent Humans

OpenAIRE

Dudok K.; Dudok T.; Vlokh I.; Vlokh R.

2005-01-01

Optical spectra of CNMetHb and CNMetHb-Coomassi G-250, taken from the blood of humans with alcohol dependence, are studied in the spectral range of 450–750nm. The shifts in the spectral absorption maxima of CNMetHb-Coomassi G-250 complexes are observed for the diseased persons with alcohol dependence. The obtained results show that the hemoglobin structure of alcohol dependent humans is changed.

Study of resistance to deformation dependence on temperature and strain degree during working with different rates for ABM-1 alloy

International Nuclear Information System (INIS)

Kharlamov, V.V.; Dvinskij, V.M.; Vashlyaev, Eh.V.; Dyblenko, Z.A.; Khamatov, R.I.; Zverev, K.P.

1981-01-01

On the basis of approximation of the experimental curves partial differential equations relating ABM-1 alloy deformation resistance to the deformation parameters are obtained. Using statistical processing of the experimental data the regression equations of the dependence of the deformation resistance on temperature rate and relative reduction of the samples are found. In the 2.1-23.6 1/c deformation rate range hardening and weakening rates of the AMB-1 alloy increases with the increase of the latter. The data obtained permit to calculate the deformation parameters of the studied alloy for different processes of metal plastic working in the studied temperature range [ru

Temperature-dependent vibrational spectroscopy to study order-disorder transitions in charge transfer complexes

Directory of Open Access Journals (Sweden)

Rohan Isaac

2018-02-01

Full Text Available Charge-transfer (CT complexes are a promising class of materials for the semiconductor industry because of their versatile properties. This class of compounds shows a variety of phase transitions, which are of interest because of their potential impact on the electronic characteristics. Here temperature-dependent vibrational spectroscopy is used to study structural phase transitions in a set of organic CT complexes. Splitting and broadening of infrared-active phonons in the complex formed between pyrene and pyromellitic dianhydride (PMDA confirm the structural transition is of the order-disorder type and complement previous x-ray diffraction (XRD results. We show that this technique is a powerful tool to characterize transitions, and apply it to a range of binary CT complexes composed of polyaromatic hyrdocarbons (anthracene, perylene, phenanthrene, pyrene, and stilbene and PMDA. We extend the understanding of transitions in perylene-PMDA and pyrene-PMDA, and show that there are no order-disorder transitions present in anthracene-PMDA, stilbene-PMDA and phenanthrene-PMDA in the temperature range investigated here.

Application of range-test in multiple linear regression analysis in ...

African Journals Online (AJOL)

Application of range-test in multiple linear regression analysis in the presence of outliers is studied in this paper. First, the plot of the explanatory variables (i.e. Administration, Social/Commercial, Economic services and Transfer) on the dependent variable (i.e. GDP) was done to identify the statistical trend over the years.

Calibration device for wide range monitor

International Nuclear Information System (INIS)

Kodoku, Masaya; Sato, Toshifumi.

1989-01-01

The calibration device for a wide range monitor according to the present invention can continuously calibrate the entire counting regions of a wide range monitor. The wide range monitor detect the reactor power in the neutron source region by means of a pulse counting method and detects the reactor power in the intermediate region by means of a cambell method. A calibration signal outputting means is disposed for continuously outputting, as such calibration signals, pulse number varying signals in which the number of pulses per unit time varies depending on the reactor power in the neutron source region to be simulated and amplitude square means varying signal in which the mean square value of amplitude varies depending on the reactor power in the intermediate region to be simulated. By using both of the calibration signals, calibration can be conducted for the nuclear reactor power in the neutron source region and the intermediate region even if the calibration is made over two regions, further, calibration for the period present over the two region can be conducted easily as well. (I.S.)

A reliability and utility study of the Care Dependency Scale

NARCIS (Netherlands)

Dijkstra, A.; Buist, G.; Moorer, P.; Dassen, T.

2000-01-01

The purpose of this study was to examine the reliability and utility of the Care Dependency Scale (CDS). This 15-item scale has been developed recently for assessing the care dependency of demented or menially handicapped inpatients. Data for this study were collected from 153 demented and 139

Structural dependence of the galvanomagnetic properties of transition-metal aluminide thin films

CERN Document Server

Kim, K W; Jeong, M H; Lee, Y P; Rhee, J Y

1999-01-01

The structural dependences of the galvanomagnetic properties of Co-Al and Fe-Al alloy films were investigated in this study. Ordered and disordered alloy films with thickness of 150 nm were prepared by using the flash evaporation technique on the heated and cooled substrates, respectively. The temperature dependence of resistance was measured in the range of 2 approx 300 K range with and without a magnetic field of 0.5 T. The influence of the order-disorder structural transition on the temperature dependence of the resistance is discussed in connection with the results for the magnetic properties and is analyzed in the framework of the partial localization of the electronic states and variable-range hopping conductivity.

Temperature dependence of exchange bias in (NiFe/IrMn)n multilayer films studied through static and dynamic techniques

Science.gov (United States)

Adams, Daniel J.; Khanal, Shankar; Khan, Mohammad Asif; Maksymov, Artur; Spinu, Leonard

2018-05-01

The in-plane temperature dependence of exchange bias was studied through both dc magnetometry and ferromagnetic resonance spectroscopy in a series of [NiFe/IrMn]n multilayer films, where n is the number of layer repetitions. Major hysteresis loops were recorded in the temperature range of 300 K to 2 K to reveal the effect of temperature on the exchange bias in the static regime while temperature-dependent continuous-wave ferromagnetic resonance for frequencies from 3 to 16 GHz was used to determine the exchange bias dynamically. Strong divergence between the values of exchange bias determined using the two different types of measurements as well as a peak in temperature dependence of the resonance linewidth were observed. These results are explained in terms of the slow-relaxer mechanism.

Long-range carbon-proton spin-spin coupling constants in conformational analysis

International Nuclear Information System (INIS)

Spoormaker, T.

1979-01-01

The author has collected a reliable set of data on long range 13 C- 1 H coupling constants in aliphatic compounds and developed the use of long range 13 C- 1 H coupling constants as a tool in the conformational analysis of aliphatic compounds. An empirical determination of the torsion angle dependence of the vicinal 13 C- 1 H coupling constant for model compounds is described and the dependence of long range 13 C- 1 H coupling constants on the electronegativity of substituents attached to the coupling pathway reported for the monohalogen substituted ethanes and propanes. The electronegativity dependence of the vicinal 13 C- 1 H coupling was studied in monosubstituted propanes whose substituents are elements from the first row of the periodic table and it is shown that the vicinal 13 C- 1 H coupling constant in aliphatic systems is a constitutive property. The geminal 13 C- 1 H coupling constants in ethyl, isopropyl and tert-butyl compounds, which have been substituted by an element of the first row of the periodic table or a haline atom, are reported and the influence of electronegative substituents on the vicinal 13 C- 1 H coupling constants in the individual rotamers of 13 CH 3 -C(X)H-C(Y)H- 1 H fragments discussed. The application of long range 13 C- 1 H coupling constants to the conformational analysis of CMP-N-Acetylneuraminic acid and 2,6-dichloro-1,4-oxathiane is described. (Auth.)

Pitch range variations improve cognitive processing of audio messages

OpenAIRE

Rodero Antón, Emma; Potter, Rob F.; Prieto Vives, Pilar, 1965-

2017-01-01

This study explores the effect of different speaker intonation strategies in audio messages on attention, autonomic arousal, and memory. An experiment was conducted in which participants listened to 16 radio commercials produced to vary in pitch range across sentences. Dependent variables were self-reported effectiveness and adequacy, psychophysiological arousal and attention, immediate word recall and recognition of information. Results showed that messages conveyed with pitch variations ach...

Extended parametric gain range in photonic crystal fibers with strongly frequency-dependent field distributions

DEFF Research Database (Denmark)

Petersen, Sidsel Rübner; Alkeskjold, Thomas Tanggaard; Olausson, Christina Bjarnal Thulin

2014-01-01

The parametric gain range of a degenerate four-wave mixing process is determined in the undepleted pump regime. The gain range is considered with and without taking the mode field distributions of the four-wave mixing components into account. It is found that the mode field distributions have...

Conductance of partially disordered graphene: crossover from temperature-dependent to field-dependent variable-range hopping

International Nuclear Information System (INIS)

Cheah, C Y; Jaurigue, L C; Kaiser, A B; Gómez-Navarro, C

2013-01-01

We report an analysis of low-temperature measurements of the conductance of partially disordered reduced graphene oxide, finding that the data follow a simple crossover scenario. At room temperature, the conductance is dominated by two-dimensional (2D) electric field-assisted, thermally driven (Pollak–Riess) variable-range hopping (VRH) through highly disordered regions. However, at lower temperatures T, we find a smooth crossover to follow the exp(−E 0 /E) 1/3 field-driven (Shklovskii) 2D VRH conductance behaviour when the electric field E exceeds a specific crossover value E C (T) 2D =(E a E 0 1/3 /3) 3/4 determined by the scale factors E 0 and E a for the high-field and intermediate-field regimes respectively. Our crossover scenario also accounts well for experimental data reported by other authors for three-dimensional disordered carbon networks, suggesting wide applicability. (paper)

Study on the angular dependence of personal exposure dosimeter - Focus on thermoluminescent dosimeter and photoluminescent dosimeter

International Nuclear Information System (INIS)

Dong, Kyung-Rae; Kweon, Dae Cheol; Chung, Woon-Kwan; Goo, Eun-Hoe; Dieter, Kevin; Choe, Chong-Hwan

2011-01-01

Radiation management departments place more emphasis on the accuracy of measurements than on the increase in the average dose and personal exposure dose from the use of radiation equipment and radioactive isotopes. Although current measurements are taken using devices, such as film badge dosimeters, pocket dosimeters and thermoluminescent dosimeters (TLDs), this study compared the angular dependence between the widely used TLDs and photoluminescent dosimeter (PLDs) in order to present primary data and evaluate the utility of PLD as a new dosimeter device. For X-ray fluoroscopy, a whole body phantom was placed on a table with a setting for the G-I technical factors fixed at a range of approximately 40 cm with a range of ±90 o at an interval scale of 15 o from the center location of an average radiological worker for PLDs (GD-450) and TLDs (Carot). This process was repeated 10 times, and at each time, the cumulative dosage was interpreted from 130 dosimeters using TLDs (UD-710R, Panasonic) and PLDs (FGD-650). The TLD and PLD showed a 52% and 23% decrease in the depth dosage from 0 o to -90 o , respectively. Therefore, PLDs have a lower angular dependence than TLDs.

Unusual features of long-range density fluctuations in glass-forming organic liquids: A Rayleigh and Rayleigh-Brillouin light scattering study

International Nuclear Information System (INIS)

Patkowski, A.; Fischer, E. W.; Steffen, W.; Glaser, H.; Baumann, M.; Ruths, T.; Meier, G.

2001-01-01

A new feature of glass-forming liquids, i.e., long-range density fluctuations of the order of 100 nm, has been extensively characterized by means of static light scattering, photon correlation spectroscopy and Rayleigh-Brillouin spectroscopy in orthoterphenyl (OTP) and 1,1-di(4 # prime#-methoxy-5 # prime#methyl-phenyl)-cyclohexane (BMMPC). These long-range density fluctuations result in the following unusual features observed in a light scattering experiment, which are not described by the existing theories: (i) strong q-dependent isotropic excess Rayleigh intensity, (ii) additional slow component in the polarized photon correlation function, and (iii) high Landau-Placzek ratio. These unusual features are equilibrium properties of the glass-forming liquids and depend only on temperature, provided that the sample has been equilibrated long enough. The temperature-dependent equilibration times were measured for BMMPC and are about 11 orders of magnitude longer than the α process. It was found that the glass-forming liquid OTP may occur in two states: with and without long-range density fluctuations ('clusters'). We have characterized the two states by static and dynamic light scattering in the temperature range from T g to T g +200 K. The relaxation times of the α process as well as the parameters of the Brillouin line are identical in both OTP with and without clusters. The α process (density fluctuations) in OTP was characterized by measuring either the polarized (VV) or depolarized (VH) correlation function, which are practically identical and q-independent. This feature, which is commonly observed in glass-forming liquids, is not fully explained by the existing theories

The juggling act: Do student nurses who care for dependants need an adapted course? An applied policy research study.

Science.gov (United States)

Kiernan, Matthew D; Proud, Carole; Jackson, Sue

2015-11-01

In line with many countries worldwide, the Department of Health mandate to Health Education England seeks to promote the diversity of applicants by widening participation in nurse education. A number of studies have explored the experience of non-traditional students undertaking nursing courses. This study aimed to explore and understand the experiences of student nurses undertaking their nurse education whilst caring for dependant family. The study used an applied qualitative research approached based on methods developed for applied social policy research. The study was undertaken in an institution of higher education in the North East of England. The study population consisted of a convenience sample of 14 respondents, 13 female and 1 male. Ten respondents lived with partners and 3 had disabled dependants within the family. The age range of dependent children ranged from 3months to 19years. Data was collected through focus groups and telephone interviews using a semi-structured interview schedule. Framework analysis was used to analyse the data. Three superordinate themes were identified, Altruism and Commitment, Maturity and Family and Social Mobility, that best encapsulate the characteristics that enable this group to function well and complete their nurse education. Analysis identified a highly motivated group of students who's individual accounts showed that their lives, whilst in nurse education, were a constant series of compromises and 'juggling' between the demands of the course and the demands of their families. This group of students do not need an adapted course, but instead wish for a realistic nursing course where expectations are managed in an honest way. Basic common sense and good management of nursing courses will help ensure that this motivated group of people achieve their goals with minimum hardship or difficulties. Copyright © 2015 Elsevier Ltd. All rights reserved.

Temperature dependence of the elastocaloric effect in natural rubber

Energy Technology Data Exchange (ETDEWEB)

Xie, Zhongjian, E-mail: zhongjian.xie521@gmail.com; Sebald, Gael; Guyomar, Daniel

2017-07-12

The temperature dependence of the elastocaloric (eC) effect in natural rubber (NR) has been studied. This material exhibits a large eC effect over a broad temperature range from 0 °C to 49 °C. The maximum adiabatic temperature change (ΔT) occurred at 10 °C and the behavior could be predicted by the temperature dependence of the strain-induced crystallization (SIC) and the temperature-induced crystallization (TIC). The eC performance of NR was then compared with that of shape memory alloys (SMAs). This study contributes to the SIC research of NR and also broadens the application of elastomers. - Highlights: • A large elastocaloric effect over a broad temperature range was found in natural rubber (NR). • The caloric performance of NR was compared with that of shape memory alloys. • The temperature dependence of the elastocaloric effect in NR can be prediced by the theory of strain-induced crystallization.

Super-ranging. A new ranging strategy in European badgers.

Directory of Open Access Journals (Sweden)

Aoibheann Gaughran

Full Text Available We monitored the ranging of a wild European badger (Meles meles population over 7 years using GPS tracking collars. Badger range sizes varied seasonally and reached their maximum in June, July and August. We analysed the summer ranging behaviour, using 83 home range estimates from 48 individuals over 6974 collar-nights. We found that while most adult badgers (males and females remained within their own traditional social group boundaries, several male badgers (on average 22% regularly ranged beyond these traditional boundaries. These adult males frequently ranged throughout two (or more social group's traditional territories and had extremely large home ranges. We therefore refer to them as super-rangers. While ranging across traditional boundaries has been recorded over short periods of time for extraterritorial mating and foraging forays, or for pre-dispersal exploration, the animals in this study maintained their super-ranges from 2 to 36 months. This study represents the first time such long-term extra-territorial ranging has been described for European badgers. Holding a super-range may confer an advantage in access to breeding females, but could also affect local interaction networks. In Ireland & the UK, badgers act as a wildlife reservoir for bovine tuberculosis (TB. Super-ranging may facilitate the spread of disease by increasing both direct interactions between conspecifics, particularly across social groups, and indirect interactions with cattle in their shared environment. Understanding super-ranging behaviour may both improve our understanding of tuberculosis epidemiology and inform future control strategies.

Long-range eye tracking: A feasibility study

Energy Technology Data Exchange (ETDEWEB)

Jayaweera, S.K.; Lu, Shin-yee

1994-08-24

The design considerations for a long-range Purkinje effects based video tracking system using current technology is presented. Past work, current experiments, and future directions are thoroughly discussed, with an emphasis on digital signal processing techniques and obstacles. It has been determined that while a robust, efficient, long-range, and non-invasive eye tracking system will be difficult to develop, such as a project is indeed feasible.

Women, drug dependency and consequences: a study from a developing country.

Science.gov (United States)

Khajedaluee, Mohammad; Dadgarmoghaddam, Maliheh; Erfanian, Majidreza; Alipourtabrizi, Arash; Khadem-Rezaiyan, Majid

2015-01-01

Introduction. Addiction in women can expose them to malnutrition, high blood pressure, cancer, and some other dangerous diseases like hepatitis, AIDS, or other sexual transmitted diseases. The aim of this study was to assess illegal sexual relations in three groups of women. Methods. This is a cross-sectional study that was done on 236 girls and young women aged 16-25 years in 2012 in three groups: vulnerable women who have substance dependency (crimes that had made women incarcerated were considered as vulnerability in this study), invulnerable women who have substance dependency (substance dependent women without a history of incarceration), and a control group (women with no history of substance dependency or being in prison). Results. 43.8% of vulnerable women who have substance dependency had extramarital sexual relations; this percentage was 55.8% in invulnerable women who have substance dependency and 1.4% in the control group. Crystal and methamphetamine abuse was higher in addicts who had extramarital sexual relations and alcohol abuse was correlated with unsafe sexual intercourse (r = 0.36, P = 0.001). There was a statistically significant difference in extramarital sexual relation based on marital status (P Poverty, drug dependency, divorce, and alcohol consumption make women prone to other high risk behaviors that need more attention.

Nuclear matter studies with density-dependent meson-nucleon coupling constants

International Nuclear Information System (INIS)

Banerjee, M.K.; Tjon, J.A.; Banerjee, M.K.; Tjon, J.A.

1997-01-01

Due to the internal structure of the nucleon, we should expect, in general, that the effective meson nucleon parameters may change in nuclear medium. We study such changes by using a chiral confining model of the nucleon. We use density-dependent masses for all mesons except the pion. Within a Dirac-Brueckner analysis, based on the relativistic covariant structure of the NN amplitude, we show that the effect of such a density dependence in the NN interaction on the saturation properties of nuclear matter, while not large, is quite significant. Due to the density dependence of the g σNN , as predicted by the chiral confining model, we find, in particular, a looping behavior of the binding energy at saturation as a function of the saturation density. A simple model is described, which exhibits looping and which is shown to be mainly caused by the presence of a peak in the density dependence of the medium modified σN coupling constant at low density. The effect of density dependence of the coupling constants and the meson masses tends to improve the results for E/A and density of nuclear matter at saturation. From the present study we see that the relationship between binding energy and saturation density may not be as universal as found in nonrelativistic studies and that more model dependence is exhibited once medium modifications of the basic nuclear interactions are considered. copyright 1997 The American Physical Society

THE PRELIMINARY STUDIES ON THE INFLUENCE OF SHOOTING RANGES ON ENVIRONMENT

Directory of Open Access Journals (Sweden)

Karolina Wodnik

2017-08-01

Full Text Available The aim of the study was to assess the impact of the shooting activity on the environment. The studies were conducted in the area of the sports shooting range. The invertebrates assemblages were identified to the family level as well as morphospecies. The second method do not require the proficiency in identification. The following indices of the biodiversity were used for the assessment of the impact of sports shooting ranges: Simpson, Shannon-Wiener, Margalef, Berger-Parker and Menhinick. A decreased biodiversity was observed at two studied sites comparing to the reference site what proves the influence of shooting activity on the biodiversity and suggest disturbance of the ecosystem integrity because of shooting activity.

Netherlands Army Long Range Anti Armour Study - Status Report

NARCIS (Netherlands)

Schagen, P.A.B. van

1989-01-01

At the end of the nineties the munition for the TOW weapon system in use at The Netherlands army, has to be replaced. The Life of Type of The Tow carrier ends in 2005. The long range anti armour study is to gain insight into the possibilities and limitations for the Netherlands army to deploy future

A Range Correction for Icesat and Its Potential Impact on Ice-sheet Mass Balance Studies

Science.gov (United States)

Borsa, A. A.; Moholdt, G.; Fricker, H. A.; Brunt, Kelly M.

2014-01-01

We report on a previously undocumented range error in NASA's Ice, Cloud and land Elevation Satellite (ICESat) that degrades elevation precision and introduces a small but significant elevation trend over the ICESat mission period. This range error (the Gaussian-Centroid or 'G-C'offset) varies on a shot-to-shot basis and exhibits increasing scatter when laser transmit energies fall below 20 mJ. Although the G-C offset is uncorrelated over periods less than1 day, it evolves over the life of each of ICESat's three lasers in a series of ramps and jumps that give rise to spurious elevation trends of -0.92 to -1.90 cm yr(exp -1), depending on the time period considered. Using ICESat data over the Ross and Filchner-Ronne ice shelves we show that (1) the G-C offset introduces significant biases in ice-shelf mass balance estimates, and (2) the mass balance bias can vary between regions because of different temporal samplings of ICESat.We can reproduce the effect of the G-C offset over these two ice shelves by fitting trends to sample-weighted mean G-C offsets for each campaign, suggesting that it may not be necessary to fully repeat earlier ICESat studies to determine the impact of the G-C offset on ice-sheet mass balance estimates.

Long-range transport and global fractionation of POPs: insights from multimedia modeling studies

International Nuclear Information System (INIS)

Scheringer, M.; Salzmann, M.; Stroebe, M.; Wegmann, F.; Fenner, K.; Hungerbuehler, K.

2004-01-01

The long-range transport of persistent organic pollutants (POPs) is investigated with two multimedia box models of the global system. ChemRange is a purely evaluative, one-dimensional steady-state (level III) model; CliMoChem is a two-dimensional model with different temperatures, land/water ratios and vegetation types in different latitudinal zones. Model results are presented for three case studies: (i) the effect of atmospheric aerosol particles on the long-range transport of POPs, (ii) the effect of oceanic deposition on the long-range transport of different PCB congeners, (iii) the global fractionation of different PCB congeners. The model results for these case studies show: (i) the low atmospheric half-lives estimated for several organochlorine pesticides are likely to be inconsistent with the observed long-range transport of these compounds; (ii) export to the deep sea reduces the potential for long-range transport of highly hydrophobic compounds (but does not remove these chemicals from the biosphere); (iii) there are different meanings of the term global fractionation that refer to different aspects of the fractionation process and need to be distinguished. The case-study results further indicate that the influences of varying environmental conditions on the physicochemical properties and the degradation rate constants of POPs need to be determined. - Multimedia box models are applied to case studies of the behavior of POPs

Optimal Target Range of Closed-Loop Inspired Oxygen Support in Preterm Infants: A Randomized Cross-Over Study.

Science.gov (United States)

van den Heuvel, Maria Elisabeth Nicoletta; van Zanten, Henriette A; Bachman, Tom E; Te Pas, Arjan B; van Kaam, Anton H; Onland, Wes

2018-06-01

To investigate the effect of different pulse oximetry (SpO 2 ) target range settings during automated fraction of inspired oxygen control (A-FiO 2 ) on time spent within a clinically set SpO 2 alarm range in oxygen-dependent infants on noninvasive respiratory support. Forty-one preterm infants (gestational age [median] 26 weeks, age [median] 21 days) on FiO 2  >0.21 receiving noninvasive respiratory support were subjected to A-FiO 2 using 3 SpO 2 target ranges (86%-94%, 88%-92%, or 89%-91%) in random order for 24 hours each. Before switching to the next target range, SpO 2 was manually controlled for 24 hours (washout period). The primary outcome was the time spent within the clinically set alarm limits of 86%-94%. The percent time within the 86%-94% SpO 2 alarm range was similar for all 3 A-FiO 2 target ranges (74%). Time spent in hyperoxemia was not significantly different between target ranges. However, the time spent in severe hypoxemia (SpO 2  target ranges of A-FiO 2 (88%-92%; 1.9%, 89%-91%; 1.7%) compared with the wide target range (86%-94%; 3.4%, P target range. Narrowing the target range of A-FiO 2 to the desired median ±2% is effective in reducing the time spent in hypoxemia, without increasing the risk of hyperoxemia. www.trialregister.nl: NTR4368. Copyright © 2018 Elsevier Inc. All rights reserved.

First in situ TOF-PET study using digital photon counters for proton range verification.

Science.gov (United States)

Cambraia Lopes, P; Bauer, J; Salomon, A; Rinaldi, I; Tabacchini, V; Tessonnier, T; Crespo, P; Parodi, K; Schaart, D R

2016-08-21

Positron emission tomography (PET) is the imaging modality most extensively tested for treatment monitoring in particle therapy. Optimal use of PET in proton therapy requires in situ acquisition of the relatively strong (15)O signal due to its relatively short half-life (~2 min) and high oxygen content in biological tissues, enabling shorter scans that are less sensitive to biological washout. This paper presents the first performance tests of a scaled-down in situ time-of-flight (TOF) PET system based on digital photon counters (DPCs) coupled to Cerium-doped Lutetium Yttrium Silicate (LYSO:Ce) crystals, providing quantitative results representative of a dual-head tomograph that complies with spatial constraints typically encountered in clinical practice (2  ×  50°, of 360°, transaxial angular acceptance). The proton-induced activity inside polymethylmethacrylate (PMMA) and polyethylene (PE) phantoms was acquired within beam pauses (in-beam) and immediately after irradiation by an actively-delivered synchrotron pencil-beam, with clinically relevant 125.67 MeV/u, 4.6  ×  10(8) protons s(-1), and 10(10) total protons. 3D activity maps reconstructed with and without TOF information are compared to FLUKA simulations, demonstrating the benefit of TOF-PET to reduce limited-angle artefacts using a 382 ps full width at half maximum coincidence resolving time. The time-dependent contributions from different radionuclides to the total count-rate are investigated. We furthermore study the impact of the acquisition time window on the laterally integrated activity depth-profiles, with emphasis on 2 min acquisitions starting at different time points. The results depend on phantom composition and reflect the differences in relative contributions from the radionuclides originating from carbon and oxygen. We observe very good agreement between the shapes of the simulated and measured activity depth-profiles for post-beam protocols. However, our results

Women, Drug Dependency and Consequences: A Study from a Developing Country

Directory of Open Access Journals (Sweden)

Mohammad Khajedaluee

2015-01-01

Full Text Available Introduction. Addiction in women can expose them to malnutrition, high blood pressure, cancer, and some other dangerous diseases like hepatitis, AIDS, or other sexual transmitted diseases. The aim of this study was to assess illegal sexual relations in three groups of women. Methods. This is a cross-sectional study that was done on 236 girls and young women aged 16–25 years in 2012 in three groups: vulnerable women who have substance dependency (crimes that had made women incarcerated were considered as vulnerability in this study, invulnerable women who have substance dependency (substance dependent women without a history of incarceration, and a control group (women with no history of substance dependency or being in prison. Results. 43.8% of vulnerable women who have substance dependency had extramarital sexual relations; this percentage was 55.8% in invulnerable women who have substance dependency and 1.4% in the control group. Crystal and methamphetamine abuse was higher in addicts who had extramarital sexual relations and alcohol abuse was correlated with unsafe sexual intercourse (r=;0.36, P=0.001. There was a statistically significant difference in extramarital sexual relation based on marital status (P<0.001. Conclusions. Poverty, drug dependency, divorce, and alcohol consumption make women prone to other high risk behaviors that need more attention.

EEG spectral phenotypes: heritability and association with marijuana and alcohol dependence in an American Indian community study.

Science.gov (United States)

Ehlers, Cindy L; Phillips, Evelyn; Gizer, Ian R; Gilder, David A; Wilhelmsen, Kirk C

2010-01-15

Native Americans have some of the highest rates of marijuana and alcohol use and abuse, yet neurobiological measures associated with dependence on these substances in this population remain unknown. The present investigation evaluated the heritability of spectral characteristics of the electroencephalogram (EEG) and their correlation with marijuana and alcohol dependence in an American Indian community. Participants (n=626) were evaluated for marijuana (MJ) and alcohol (ALC) dependence, as well as other psychiatric disorders. EEGs were collected from six cortical sites and spectral power determined in five frequency bands (delta 1.0-4.0 Hz, theta 4.0-7.5 Hz, alpha 7.5-12.0 Hz, low beta 12.0-20.0 Hz and high beta/gamma 20-50 Hz). The estimated heritability (h(2)) of the EEG phenotypes was calculated using SOLAR, and ranged from 0.16 to 0.67. Stepwise linear regression was used to detect correlations between MJ and ALC dependence and the spectral characteristics of the EEG using a model that took into account: age, gender, Native American Heritage (NAH) and a lifetime diagnosis of antisocial personality and/or conduct disorder (ASPD/CD). Increases in spectral power in the delta frequency range, were significantly correlated with gender (pEEG delta and high beta/gamma activity are correlated with MJ dependence and alcohol dependence, respectively, in this community sample of Native Americans. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

Compact range for variable-zone measurements

Science.gov (United States)

Burnside, Walter D.; Rudduck, Roger C.; Yu, Jiunn S.

1988-08-02

A compact range for testing antennas or radar targets includes a source for directing energy along a feedline toward a parabolic reflector. The reflected wave is a spherical wave with a radius dependent on the distance of the source from the focal point of the reflector.

Azimuthal angle dependence of Coulomb and nuclear interactions between two deformed nuclei

International Nuclear Information System (INIS)

Ismail, M.; Ellithi, A. Y.; Botros, M. M.; Mellik, A. E.

2007-01-01

The azimuthal angle (φ) variation of the Coulomb and nuclear heavy ion (HI) potentials is studied in the framework of the double folding model, which is derived from realistic nuclear density distributions and a nucleon-nucleon (NN) interaction. The present calculation shows that the variation of HI potentials with the azimuthal angle depends strongly on the range of the NN forces. For the long-range Coulomb force, the maximum variation with φ is about 0.9%, and for HI potential derived from zero-range NN interaction the φ-variation can reach up to 90.0%. Our calculations are compared with the recent φ-dependence of the HI potential derived from proximity method. The present realistic φ-dependence calculations of the HI potential is completely different from the results of the proximity calculations

The rate of beneficial mutations surfing on the wave of a range expansion.

Directory of Open Access Journals (Sweden)

Rémi Lehe

Full Text Available Many theoretical and experimental studies suggest that range expansions can have severe consequences for the gene pool of the expanding population. Due to strongly enhanced genetic drift at the advancing frontier, neutral and weakly deleterious mutations can reach large frequencies in the newly colonized regions, as if they were surfing the front of the range expansion. These findings raise the question of how frequently beneficial mutations successfully surf at shifting range margins, thereby promoting adaptation towards a range-expansion phenotype. Here, we use individual-based simulations to study the surfing statistics of recurrent beneficial mutations on wave-like range expansions in linear habitats. We show that the rate of surfing depends on two strongly antagonistic factors, the probability of surfing given the spatial location of a novel mutation and the rate of occurrence of mutations at that location. The surfing probability strongly increases towards the tip of the wave. Novel mutations are unlikely to surf unless they enjoy a spatial head start compared to the bulk of the population. The needed head start is shown to be proportional to the inverse fitness of the mutant type, and only weakly dependent on the carrying capacity. The precise location dependence of surfing probabilities is derived from the non-extinction probability of a branching process within a moving field of growth rates. The second factor is the mutation occurrence which strongly decreases towards the tip of the wave. Thus, most successful mutations arise at an intermediate position in the front of the wave. We present an analytic theory for the tradeoff between these factors that allows to predict how frequently substitutions by beneficial mutations occur at invasion fronts. We find that small amounts of genetic drift increase the fixation rate of beneficial mutations at the advancing front, and thus could be important for adaptation during species invasions.

Unsynchronized scanning with a low-cost laser range finder for real-time range imaging

Science.gov (United States)

Hatipoglu, Isa; Nakhmani, Arie

2017-06-01

Range imaging plays an essential role in many fields: 3D modeling, robotics, heritage, agriculture, forestry, reverse engineering. One of the most popular range-measuring technologies is laser scanner due to its several advantages: long range, high precision, real-time measurement capabilities, and no dependence on lighting conditions. However, laser scanners are very costly. Their high cost prevents widespread use in applications. Due to the latest developments in technology, now, low-cost, reliable, faster, and light-weight 1D laser range finders (LRFs) are available. A low-cost 1D LRF with a scanning mechanism, providing the ability of laser beam steering for additional dimensions, enables to capture a depth map. In this work, we present an unsynchronized scanning with a low-cost LRF to decrease scanning period and reduce vibrations caused by stop-scan in synchronized scanning. Moreover, we developed an algorithm for alignment of unsynchronized raw data and proposed range image post-processing framework. The proposed technique enables to have a range imaging system for a fraction of the price of its counterparts. The results prove that the proposed method can fulfill the need for a low-cost laser scanning for range imaging for static environments because the most significant limitation of the method is the scanning period which is about 2 minutes for 55,000 range points (resolution of 250x220 image). In contrast, scanning the same image takes around 4 minutes in synchronized scanning. Once faster, longer range, and narrow beam LRFs are available, the methods proposed in this work can produce better results.

Theoretical and computational study of the energy dependence of the muon transfer rate from hydrogen to higher-Z gases

Energy Technology Data Exchange (ETDEWEB)

Bakalov, Dimitar, E-mail: dbakalov@inrne.bas.bg [Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Tsarigradsko chaussée 72, Sofia 1784 (Bulgaria); Adamczak, Andrzej [Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, 31-342 Krakow (Poland); Stoilov, Mihail [Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Tsarigradsko chaussée 72, Sofia 1784 (Bulgaria); Vacchi, Andrea [Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, Via A. Valerio 2, 34127 Trieste (Italy)

2015-01-23

The recent PSI Lamb shift experiment and the controversy about proton size revived the interest in measuring the hyperfine splitting in muonic hydrogen as an alternative possibility for comparing ordinary and muonic hydrogen spectroscopy data on proton electromagnetic structure. This measurement critically depends on the energy dependence of the muon transfer rate to heavier gases in the epithermal range. The available data provide only qualitative information, and the theoretical predictions have not been verified. We propose a new method by measurements of the transfer rate in thermalized target at different temperatures, estimate its accuracy and investigate the optimal experimental conditions. - Highlights: • Method for measuring the energy dependence of muon transfer rate to higher-Z gases. • Thermalization and depolarization of muonic hydrogen studied by Monte Carlo method. • Optimal experimental conditions determined by Monte Carlo simulations. • Mathematical model and for estimating the uncertainty of the experimental results.

Prescription Pain Reliever Abuse and Dependence among Adolescents: A Nationally Representative Study

Science.gov (United States)

Wu, Li-Tzy; Ringwalt, Christopher L.; Mannelli, Paolo; Patkar, Ashwin A.

2008-01-01

The study investigates the prevalence, patterns, and correlates of adolescents' abuse, sub-threshold dependence, and dependence on prescription pain relievers (PPRs) in a nationally representative sample. Results show dependence on PPRs can take place without abuse and that sub-threshold dependence could have implications for major diagnostic…

Effect of interaction range on phonon relaxation in Fermi-Pasta-Ulam beta chain.

Science.gov (United States)

Santhosh, G; Kumar, Deepak

2007-08-01

We study the effect of increasing the range of interactions on phonon relaxation in a chain of atoms with quartic anharmonicity. The study is motivated by recent numerical studies, showing that the value of the exponent alpha characterizing the divergence of conductivity with system size apparently depends on the presence of second neighbor couplings. We perform a quantum calculation of the wave-vector (q) dependent relaxation rate gamma(q) in the second order perturbation theory. The nonanalytic dependence of gamma(q) arises due to small-q singularity of the collision integral. We find that gamma(q) proportional to Aq(5/3) + Bq2. This gives rise to an asymptotic value alpha = 0.4, but the q2 terms lead to a higher apparent value of alpha at small sizes of the chain.

Strain rate dependency of laser sintered polyamide 12

Directory of Open Access Journals (Sweden)

Cook J.E.T.

2015-01-01

Full Text Available Parts processed by Additive Manufacturing can now be found across a wide range of applications, such as those in the aerospace and automotive industry in which the mechanical response must be optimised. Many of these applications are subjected to high rate or impact loading, yet it is believed that there is no prior research on the strain rate dependence in these materials. This research investigates the effect of strain rate and laser energy density on laser sintered polyamide 12. In the study presented here, parts produced using four different laser sintered energy densities were exposed to uniaxial compression tests at strain rates ranging from 10−3 to 10+3 s−1 at room temperature, and the dependence on these parameters is presented.

SU-C-207A-06: On-Line Beam Range Verification with Multiple Scanning Particle Beams: Initial Feasibility Study with Simulations

Energy Technology Data Exchange (ETDEWEB)

Zhong, Y; Sun, X; Lu, W; Jia, X; Wang, J; Shao, Y [The University of Texas Southwestern Medical Ctr., Dallas, TX (United States)

2016-06-15

Purpose: To investigate the feasibility and requirement for intra-fraction on-line multiple scanning particle beam range verifications (BRVs) with in-situ PET imaging, which is beyond the current single-beam BRV with extra factors that will affect the BR measurement accuracy, such as beam diameter, separation between beams, and different image counts at different BRV positions. Methods: We simulated a 110-MeV proton beam with 5-mm diameter irradiating a uniform PMMA phantom by GATE simulation, which generated nuclear interaction-induced positrons. In this preliminary study, we simply duplicated these positrons and placed them next to the initial protons to approximately mimic the two spatially separated positron distributions produced by two beams parallel to each other but with different beam ranges. These positrons were then imaged by a PET (∼2-mm resolution, 10% sensitivity, 320×320×128 mm^3 FOV) with different acquisition times. We calculated the positron activity ranges (ARs) from reconstructed PET images and compared them with the corresponding ARs of original positron distributions. Results: Without further image data processing and correction, the preliminary study show the errors between the measured and original ARs varied from 0.2 mm to 2.3 mm as center-to-center separations and range differences were in the range of 8–12 mm and 2–8 mm respectively, indicating the accuracy of AR measurement strongly depends on the beam separations and range differences. In addition, it is feasible to achieve ≤ 1.0-mm accuracy for both beams with 1-min PET acquisition and 12 mm beam separation. Conclusion: This study shows that the overlap between the positron distributions from multiple scanning beams can significantly impact the accuracy of BRVs of distributed particle beams and need to be further addressed beyond the established method of single-beam BRV, but it also indicates the feasibility to achieve accurate on-line multi-beam BRV with further improved

Long-Term Outcome in Pyridoxine-Dependent Epilepsy

Science.gov (United States)

Bok, Levinus A.; Halbertsma, Feico J..; Houterman, Saskia; Wevers, Ron A.; Vreeswijk, Charlotte; Jakobs, Cornelis; Struys, Eduard; van der Hoeven, Johan H.; Sival, Deborah A.; Willemsen, Michel A.

2012-01-01

Aim: The long-term outcome of the Dutch pyridoxine-dependent epilepsy cohort and correlations between patient characteristics and follow-up data were retrospectively studied. Method: Fourteen patients recruited from a national reference laboratory were included (four males, 10 females, from 11 families; median age at assessment 6y; range 2y…

Spatial dependence of extreme rainfall

Science.gov (United States)

Radi, Noor Fadhilah Ahmad; Zakaria, Roslinazairimah; Satari, Siti Zanariah; Azman, Muhammad Az-zuhri

2017-05-01

This study aims to model the spatial extreme daily rainfall process using the max-stable model. The max-stable model is used to capture the dependence structure of spatial properties of extreme rainfall. Three models from max-stable are considered namely Smith, Schlather and Brown-Resnick models. The methods are applied on 12 selected rainfall stations in Kelantan, Malaysia. Most of the extreme rainfall data occur during wet season from October to December of 1971 to 2012. This period is chosen to assure the available data is enough to satisfy the assumption of stationarity. The dependence parameters including the range and smoothness, are estimated using composite likelihood approach. Then, the bootstrap approach is applied to generate synthetic extreme rainfall data for all models using the estimated dependence parameters. The goodness of fit between the observed extreme rainfall and the synthetic data is assessed using the composite likelihood information criterion (CLIC). Results show that Schlather model is the best followed by Brown-Resnick and Smith models based on the smallest CLIC's value. Thus, the max-stable model is suitable to be used to model extreme rainfall in Kelantan. The study on spatial dependence in extreme rainfall modelling is important to reduce the uncertainties of the point estimates for the tail index. If the spatial dependency is estimated individually, the uncertainties will be large. Furthermore, in the case of joint return level is of interest, taking into accounts the spatial dependence properties will improve the estimation process.

Sampling Number Effects in 2D and Range Imaging of Range-gated Acquisition

International Nuclear Information System (INIS)

Kwon, Seong-Ouk; Park, Seung-Kyu; Baik, Sung-Hoon; Cho, Jai-Wan; Jeong, Kyung-Min

2015-01-01

In this paper, we analyzed the number effects of sampling images for making a 2D image and a range image from acquired RGI images. We analyzed the number effects of RGI images for making a 2D image and a range image using a RGI vision system. As the results, 2D image quality was not much depended on the number of sampling images but on how much well extract efficient RGI images. But, the number of RGI images was important for making a range image because range image quality was proportional to the number of RGI images. Image acquiring in a monitoring area of nuclear industry is an important function for safety inspection and preparing appropriate control plans. To overcome the non-visualization problem caused by airborne obstacle particles, vision systems should have extra-functions, such as active illumination lightening through disturbance airborne particles. One of these powerful active vision systems is a range-gated imaging system. The vision system based on the range-gated imaging system can acquire image data from raining or smoking environments. Range-gated imaging (RGI) is a direct active visualization technique using a highly sensitive image sensor and a high intensity illuminant. Currently, the range-gated imaging technique providing 2D and 3D images is one of emerging active vision technologies. The range-gated imaging system gets vision information by summing time sliced vision images. In the RGI system, a high intensity illuminant illuminates for ultra-short time and a highly sensitive image sensor is gated by ultra-short exposure time to only get the illumination light. Here, the illuminant illuminates objects by flashing strong light through airborne disturbance particles. Thus, in contrast to passive conventional vision systems, the RGI active vision technology robust for low-visibility environments

Sampling Number Effects in 2D and Range Imaging of Range-gated Acquisition

Energy Technology Data Exchange (ETDEWEB)

Kwon, Seong-Ouk; Park, Seung-Kyu; Baik, Sung-Hoon; Cho, Jai-Wan; Jeong, Kyung-Min [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-10-15

In this paper, we analyzed the number effects of sampling images for making a 2D image and a range image from acquired RGI images. We analyzed the number effects of RGI images for making a 2D image and a range image using a RGI vision system. As the results, 2D image quality was not much depended on the number of sampling images but on how much well extract efficient RGI images. But, the number of RGI images was important for making a range image because range image quality was proportional to the number of RGI images. Image acquiring in a monitoring area of nuclear industry is an important function for safety inspection and preparing appropriate control plans. To overcome the non-visualization problem caused by airborne obstacle particles, vision systems should have extra-functions, such as active illumination lightening through disturbance airborne particles. One of these powerful active vision systems is a range-gated imaging system. The vision system based on the range-gated imaging system can acquire image data from raining or smoking environments. Range-gated imaging (RGI) is a direct active visualization technique using a highly sensitive image sensor and a high intensity illuminant. Currently, the range-gated imaging technique providing 2D and 3D images is one of emerging active vision technologies. The range-gated imaging system gets vision information by summing time sliced vision images. In the RGI system, a high intensity illuminant illuminates for ultra-short time and a highly sensitive image sensor is gated by ultra-short exposure time to only get the illumination light. Here, the illuminant illuminates objects by flashing strong light through airborne disturbance particles. Thus, in contrast to passive conventional vision systems, the RGI active vision technology robust for low-visibility environments.

[Confirmative study of a French version of the Exercise Dependence Scale-revised with a French population].

Science.gov (United States)

Allegre, B; Therme, P

2008-10-01

Since the first writings on excessive exercise, there has been an increased interest in exercise dependence. One of the major consequences of this increased interest has been the development of several definitions and measures of exercise dependence. The work of Veale [Does primary exercise dependence really exist? In: Annet J, Cripps B, Steinberg H, editors. Exercise addiction: Motivation for participation in sport and exercise.Leicester, UK: Br Psychol Soc; 1995. p. 1-5.] provides an advance for the definition and measure of exercise dependence. These studies have adapted the DSM-IV criteria for substance dependence to measure exercise dependence. The Exercise Dependence Scale-Revised is based on these diagnostic criteria, which are: tolerance; withdrawal effects; intention effect; lack of control; time; reductions in other activities; continuance. Confirmatory factor analyses of EDS-R provided support to present a measurement model (21 items loaded in seven factors) of EDS-R (Comparative Fit Index=0.97; Root mean Square Error of Approximation=0.05; Tucker-Lewis Index=0.96). The aim of this study was to examine the psychometric properties of a French version of the EDS-R [Factorial validity and psychometric examination of the exercise dependence scale-revised. Meas Phys Educ Exerc Sci 2004;8(4):183-201.] to test the stability of the seven-factor model of the original version with a French population. A total of 516 half-marathoners ranged in age from 17 to 74 years old (Mean age=39.02 years, ET=10.64), with 402 men (77.9%) and 114 women (22.1%) participated in the study. The principal component analysis results in a six-factor structure, which accounts for 68.60% of the total variance. Because principal component analysis presents a six-factor structure differing from the original seven-factor structure, two models were tested, using confirmatory factor analysis. The first model is the seven-factor model of the original version of the EDS-R and the second is the

Range prediction for electric vehicles; Reichweitenprognose fuer Elektromobile

Energy Technology Data Exchange (ETDEWEB)

Conradi, Peter [All4IP Technologies GmbH and Co.KG, Darmstadt (Germany)

2012-06-15

The range of electric vehicles varies strongly in dependency of a number of external factors. To be able to make an exact dynamic prediction of the remaining range during the journey, All4IP Technologies developed a special software that can access the CAN bus. The App, programmed for iOS and Android operating systems considers even the topology of the area. (orig.)

Temperature dependence of radiation effects in polyethylene

International Nuclear Information System (INIS)

Wu, G; Katsumura, Y.; Kudoh, H.; Morita, Y.; Seguchi, T.

2000-01-01

Temperature dependence of crosslinking and gas evolution under γ-irradiation was studied for high-density and low-density polyethylene samples in the 30-360degC range. It was found that crosslinking was the predominant process up to 300degC and the gel point decreased with increasing temperature. At above 300degC, however, the gel fraction at a given dose decreased rapidly with temperature and the action of radiation turned to enhance polyethylene degradation. Yields of H 2 and hydrocarbon gases increased with temperature and the compositions of hydrocarbons were dose dependent. (author)

Study of an Ising model with competing long- and short-range interactions

International Nuclear Information System (INIS)

Loew, U.; Emery, V.J.; Fabricius, K.; Kivelson, S.A.

1994-01-01

A classical spin-one lattice gas model is used to study the competition between short-range ferromagnetic coupling and long-range antiferromagnetic Coulomb interactions. The model is a coarse-grained representation of frustrated phase separation in high-temperature superconductors. The ground states are determined for the complete range of parameters by using a combination of numerical and analytical techniques. The crossover between ferromagnetic and antiferromagnetic states proceeds via a rich structure of highly symmetric striped and checkerboard phases. There is no devil's staircase behavior because mixtures of stripes with different period phase separate

Simulation of the Nonlinear Dose Dependence of Stabilized Point Defects

International Nuclear Information System (INIS)

Chen, R; Pagonis, V; Lawless, J L

2010-01-01

The dose dependence of the concentration of point defects in alkali-halides as well as other crystals, as exhibited by the dependence of the thermoluminescence (TL), optical absorption and ESR on the dose of non-ionizing UV excitation is studied using numerical simulation. The relevant set of coupled rate equations are first written and plausible sets of trapping parameters are chosen. Instead of using simplifying assumptions previously used for reaching conclusions concerning this dose behavior, exact numerical solutions have now been reached. Depending on the parameters chosen, different dose dependencies are seen. In some cases, linear dose dependence is reached in a broad range. Sublinear dose dependence, close to a D 1/2 dependence when D is the dose of excitation can be reached when retrapping is stronger than trapping in other traps stabilizing the defects. When strong competition between stabilizing traps takes place, an initial linear range is observed followed by strong superlinearity and an approach to saturation. All these behaviors have been observed experimentally in TL measurements as well as ESR and optical absorption in different materials. Similarities and dissimilarities to linear and non-linear dose dependencies obtained experimentally and by simulations when ionizing irradiation is used for excitation are discussed.

Pad A treatability study long-range project plan

International Nuclear Information System (INIS)

Mousseau, J.D.

1991-06-01

This plan addresses the work to be accomplished by the Pad A Treatability Study Project. The purpose of this project is to investigate potential treatment and separation technologies, identify the best technologies, and to demonstrate by both lab- and pilot-scale demonstration, the most applicable remedial technologies for treating plutonium-contaminated salts at the Pad A site located at the Subsurface Disposal Area (SDA) at the Radioactive Waste Management Complex (RWMC) a the Idaho National Engineering Laboratory (INEL). The conduct of this project will be supported by other DOE laboratories, universities, and private industries, who will provide support for near-term demonstrations of treatment and separation technologies. The purpose of this long-range planning document is to present the detailed plan for the implementation of the Pad A Treatability Study Project

Scale-Dependent Habitat Selection and Size-Based Dominance in Adult Male American Alligators.

Directory of Open Access Journals (Sweden)

Bradley A Strickland

Full Text Available Habitat selection is an active behavioral process that may vary across spatial and temporal scales. Animals choose an area of primary utilization (i.e., home range then make decisions focused on resource needs within patches. Dominance may affect the spatial distribution of conspecifics and concomitant habitat selection. Size-dependent social dominance hierarchies have been documented in captive alligators, but evidence is lacking from wild populations. We studied habitat selection for adult male American alligators (Alligator mississippiensis; n = 17 on the Pearl River in central Mississippi, USA, to test whether habitat selection was scale-dependent and individual resource selectivity was a function of conspecific body size. We used K-select analysis to quantify selection at the home range scale and patches within the home range to determine selection congruency and important habitat variables. In addition, we used linear models to determine if body size was related to selection patterns and strengths. Our results indicated habitat selection of adult male alligators was a scale-dependent process. Alligators demonstrated greater overall selection for habitat variables at the patch level and less at the home range level, suggesting resources may not be limited when selecting a home range for animals in our study area. Further, diurnal habitat selection patterns may depend on thermoregulatory needs. There was no relationship between resource selection or home range size and body size, suggesting size-dependent dominance hierarchies may not have influenced alligator resource selection or space use in our sample. Though apparent habitat suitability and low alligator density did not manifest in an observed dominance hierarchy, we hypothesize that a change in either could increase intraspecific interactions, facilitating a dominance hierarchy. Due to the broad and diverse ecological roles of alligators, understanding the factors that influence their

Scale-dependent habitat selection and size-based dominance in adult male American alligators

Science.gov (United States)

Strickland, Bradley A.; Vilella, Francisco; Belant, Jerrold L.

2016-01-01

Habitat selection is an active behavioral process that may vary across spatial and temporal scales. Animals choose an area of primary utilization (i.e., home range) then make decisions focused on resource needs within patches. Dominance may affect the spatial distribution of conspecifics and concomitant habitat selection. Size-dependent social dominance hierarchies have been documented in captive alligators, but evidence is lacking from wild populations. We studied habitat selection for adult male American alligators (Alligator mississippiensis; n = 17) on the Pearl River in central Mississippi, USA, to test whether habitat selection was scale-dependent and individual resource selectivity was a function of conspecific body size. We used K-select analysis to quantify selection at the home range scale and patches within the home range to determine selection congruency and important habitat variables. In addition, we used linear models to determine if body size was related to selection patterns and strengths. Our results indicated habitat selection of adult male alligators was a scale-dependent process. Alligators demonstrated greater overall selection for habitat variables at the patch level and less at the home range level, suggesting resources may not be limited when selecting a home range for animals in our study area. Further, diurnal habitat selection patterns may depend on thermoregulatory needs. There was no relationship between resource selection or home range size and body size, suggesting size-dependent dominance hierarchies may not have influenced alligator resource selection or space use in our sample. Though apparent habitat suitability and low alligator density did not manifest in an observed dominance hierarchy, we hypothesize that a change in either could increase intraspecific interactions, facilitating a dominance hierarchy. Due to the broad and diverse ecological roles of alligators, understanding the factors that influence their social dominance

Change in Care Dependency of Stroke Patients: A Longitudinal and Multicenter Study.

Science.gov (United States)

Nursiswati, Nursiswati; Halfens, Ruud J G; Lohrmann, Christa

2017-06-01

The study was conducted to investigate the change of care dependency in stroke patients from inpatient wards and outpatient units in Indonesia. This study is longitudinal and multicentered. One hundred and nine patients were included from four hospitals on the island of Java. Care dependency was assessed using the Indonesian version of the 15-item Care Dependency Scale (CDS) at five points in time: at inpatient wards for admission and discharge and at outpatient units after discharge in the 1st week, the 5th week, and the 13th week. Most of the patients were male (65.1%), and diagnosed with ischemic stroke (71.5%). The results showed that care dependency in stroke patients decreased significantly from admission to discharge, as well as from the 5th to the 13th week as measured by the CDS. At admission, 23.0% of the patients were completely dependent on care, and at the 13th week about 1.0% were. Patients' care dependency decreased significantly in all care dependency items of the CDS in the inpatient ward, but five care dependency items of the CDS did not significantly decrease in the outpatient unit. Based on the findings of this study, we recommend that hospital-based and community-based services should include continual care dependence monitoring using this comprehensive instrument. Care dependency is subject to change over time, therefore nurses have to plan and tailor adequate nursing care measures to patient needs in the different stages, especially with respect to the aspect of mobility. Copyright © 2017. Published by Elsevier B.V.

Costs of U.S. Oil Dependence: 2005 Update

Energy Technology Data Exchange (ETDEWEB)

Greene, D.L.

2005-03-08

For thirty years, dependence on oil has been a significant problem for the United States. Oil dependence is not simply a matter of how much oil we import. It is a syndrome, a combination of the vulnerability of the U.S. economy to higher oil prices and oil price shocks and a concentration of world oil supplies in a small group of oil producing states that are willing and able to use their market power to influence world oil prices. Although there are vitally important political and military dimensions to the oil dependence problem, this report focuses on its direct economic costs. These costs are the transfer of wealth from the United States to oil producing countries, the loss of economic potential due to oil prices elevated above competitive market levels, and disruption costs caused by sudden and large oil price movements. Several enhancements have been made to methods used in past studies to estimate these costs, and estimates of key parameters have been updated based on the most recent literature. It is estimated that oil dependence has cost the U.S. economy $3.6 trillion (constant 2000 dollars) since 1970, with the bulk of the losses occurring between 1979 and 1986. However, if oil prices in 2005 average $35-$45/bbl, as recently predicted by the U.S. Energy Information Administration, oil dependence costs in 2005 will be in the range of $150-$250 billion. Costs are relatively evenly divided between the three components. A sensitivity analysis reflecting uncertainty about all the key parameters required to estimate oil dependence costs suggests that a reasonable range of uncertainty for the total costs of U.S. oil dependence over the past 30 years is $2-$6 trillion (constant 2000 dollars). Reckoned in terms of present value using a discount rate of 4.5%, the costs of U.S. oil dependence since 1970 are $8 trillion, with a reasonable range of uncertainty of $5 to $13 trillion.

Oppositional defiant disorder (ODD), the forerunner of alcohol dependence: a controlled study.

Science.gov (United States)

Ghosh, Abhishek; Malhotra, Savita; Basu, Debasish

2014-10-01

There are common genetic, neurobiological and psycho-social substrates for oppositional defiant disorder (ODD) and substance dependence. ODD can be regarded as the mildest and earliest form of disruptive behavioral disorder and also represents the threshold of vulnerability for substance dependence. But it is a less researched area. The aim of this research was to study any possible association between childhood ODD and adult alcohol dependence. Data are presented from a non probability sample of 100 adult alcohol dependent subjects and equal number of biologically unrelated control subjects. Assessment was conducted by the instrument Semi-Structured Assessment for the Genetics of Alcoholism for both the assessment of ODD and alcohol dependence. The results of this study demonstrated significant association between childhood ODD and adult alcohol dependence. The association remained significant even after the exclusion of the possible confounding effects of the presence of conduct disorder and attention deficit hyperactivity disorder. Our study should encourage further research in this area and is expected to open up an opportunity for preventive research. Copyright © 2014 Elsevier B.V. All rights reserved.

Theoretical and experimental study: the size dependence of decomposition thermodynamics of nanomaterials

International Nuclear Information System (INIS)

Cui, Zixiang; Duan, Huijuan; Li, Wenjiao; Xue, Yongqiang

2015-01-01

In the processes of preparation and application of nanomaterials, the decomposition reactions of nanomaterials are often involved. However, there is a dramatic difference in decomposition thermodynamics between nanomaterials and the bulk counterparts, and the difference depends on the size of the particles that compose the nanomaterials. In this paper, the decomposition model of a nanoparticle was built, the theory of decomposition thermodynamics of nanomaterials was proposed, and the relations of the size dependence of thermodynamic quantities for the decomposition reactions were deduced. In experiment, taking the thermal decomposition of nano-Cu 2 (OH) 2 CO 3 with different particle sizes (the range of radius is at 8.95–27.4 nm) as a system, the reaction thermodynamic quantities were determined, and the regularities of size dependence of the quantities were summarized. These experimental regularities consist with the above thermodynamic relations. The results show that there is a significant effect of the size of particles composing a nanomaterial on the decomposition thermodynamics. When all the decomposition products are gases, the differences in thermodynamic quantities of reaction between the nanomaterials and the bulk counterparts depend on the particle size; while when one of the decomposition products is a solid, the differences depend on both the initial particle size of the nanoparticle and the decomposition ratio. When the decomposition ratio is very small, these differences are only related to the initial particle size; and when the radius of the nanoparticles approaches or exceeds 10 nm, the reaction thermodynamic functions and the logarithm of the equilibrium constant are linearly associated with the reciprocal of radius, respectively. The thermodynamic theory can quantificationally describe the regularities of the size dependence of thermodynamic quantities for decomposition reactions of nanomaterials, and contribute to the researches and the

Age dependence of dielectric properties of bovine brain and ocular tissues in the frequency range of 400 MHz to 18 GHz

International Nuclear Information System (INIS)

Schmid, Gernot; Ueberbacher, Richard

2005-01-01

In order to identify possible age-dependent dielectric properties of brain and eye tissues in the frequency range of 400 MHz to 18 GHz, measurements on bovine grey and white matter as well as on cornea, lens (cortical) and the vitreous body were performed using a commercially available open-ended coaxial probe and a computer-controlled vector network analyser. Freshly excised tissues of 52 animals of two age groups (42 adult animals, i.e. 16-24 month old and 10 young animals, i.e. 4-6 month old calves) were examined within 8 min (brain tissue) and 15 min (eye tissue), respectively, of the animals' death. Tissue temperatures for the measurements were 32 ± 1 0 C and 25 ± 1 0 C for brain and eye tissues, respectively. Statistical analysis of the measured data revealed significant differences in the dielectric properties of white matter and cortical lens tissue between the adult and the young group. In the case of white matter the mean values of conductivity and permittivity of young tissue were 15%-22% and 12%-15%, respectively, higher compared to the adult tissue in the considered frequency range. Similarly, young cortical lens tissue was 25%-76% higher in conductivity and 27%-39% higher in permittivity than adult cortical lens tissue

Two Generations of Path Dependence

DEFF Research Database (Denmark)

Madsen, Mogens Ove

  Even if there is no fully articulated and generally accepted theory of Path Dependence it has eagerly been taken up across a wide range of social sciences - primarily coming from economics. Path Dependence is most of all a metaphor that offers reason to believe, that some political, social...

Experimental validation of gallium production and isotope-dependent positron range correction in PET

Energy Technology Data Exchange (ETDEWEB)

Fraile, L.M., E-mail: lmfraile@ucm.es [Grupo de Física Nuclear, Dpto. Física Atómica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Herraiz, J.L.; Udías, J.M.; Cal-González, J.; Corzo, P.M.G.; España, S.; Herranz, E.; Pérez-Liva, M.; Picado, E.; Vicente, E. [Grupo de Física Nuclear, Dpto. Física Atómica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Muñoz-Martín, A. [Centro de Microanálisis de Materiales, Universidad Autónoma de Madrid, E-28049 Madrid (Spain); Vaquero, J.J. [Departamento de Bioingeniería e Ingeniería Aeroespacial, Universidad Carlos III de Madrid (Spain)

2016-04-01

Positron range (PR) is one of the important factors that limit the spatial resolution of positron emission tomography (PET) preclinical images. Its blurring effect can be corrected to a large extent if the appropriate method is used during the image reconstruction. Nevertheless, this correction requires an accurate modelling of the PR for the particular radionuclide and materials in the sample under study. In this work we investigate PET imaging with {sup 68}Ga and {sup 66}Ga radioisotopes, which have a large PR and are being used in many preclinical and clinical PET studies. We produced a {sup 68}Ga and {sup 66}Ga phantom on a natural zinc target through (p,n) reactions using the 9-MeV proton beam delivered by the 5-MV CMAM tandetron accelerator. The phantom was imaged in an ARGUS small animal PET/CT scanner and reconstructed with a fully 3D iterative algorithm, with and without PR corrections. The reconstructed images at different time frames show significant improvement in spatial resolution when the appropriate PR is applied for each frame, by taking into account the relative amount of each isotope in the sample. With these results we validate our previously proposed PR correction method for isotopes with large PR. Additionally, we explore the feasibility of PET imaging with {sup 68}Ga and {sup 66}Ga radioisotopes in proton therapy.

Reaction OH + OH studied over the 298-834 K temperature and 1-100 bar pressure ranges.

Science.gov (United States)

Sangwan, Manuvesh; Chesnokov, Evgeni N; Krasnoperov, Lev N

2012-06-21

Self-reaction of hydroxyl radicals, OH + OH → H(2)O + O (1a) and OH + OH → H(2)O(2) (1b), was studied using pulsed laser photolysis coupled to transient UV-vis absorption spectroscopy over the 298-834 K temperature and 1-100 bar pressure ranges (bath gas He). A heatable high-pressure flow reactor was employed. Hydroxyl radicals were prepared using reaction of electronically excited oxygen atoms, O((1)D), produced in photolysis of N(2)O at 193 nm, with H(2)O. The temporal behavior of OH radicals was monitored via transient absorption of light from a dc discharge in H(2)O/Ar low-pressure resonance lamp at ca. 308 nm. The absolute intensity of the photolysis light was determined by accurate in situ actinometry based on the ozone formation in the presence of molecular oxygen. The results of this study combined with the literature data indicate that the rate constant of reaction 1a, associated with the pressure independent component, decreases with temperature within the temperature range 298-414 K and increases above 555 K. The pressure dependent rate constant for (1b) was parametrized using the Troe expression as k(1b,inf) = (2.4 ± 0.6) × 10(-11)(T/300)(-0.5) cm(3) molecule(-1) s(-1), k(1b,0) = [He] (9.0 ± 2.2) × 10(-31)(T/300)(-3.5±0.5) cm(3) molecule(-1) s(-1), F(c) = 0.37.

Are experiences of sexual violence related to special needs in patients with substance use disorders? A study in opioid-dependent patients.

Science.gov (United States)

Schäfer, Ingo; Gromus, Lil; Atabaki, Armita; Pawils, Silke; Verthein, Uwe; Reimer, Jens; Schulte, Bernd; Martens, Marcus

2014-12-01

A history of sexual violence has been related to more complex treatment needs in patients with substance use disorders (SUD). Most of the existing studies, however, included patients with various types of SUD, did not examine gender differences and focused on a small range of clinical domains. Our sample consisted of opioid-dependent outpatients treated during a three-year period in a German metropolitan region. The analysis was based on a local case register and included all patients for whom information on lifetime sexual violence was available (N=3531; 68.3% males). In a case-control design, patients with a history of sexual violence were compared to patients without these experiences regarding a wide range of clinical and social factors indicative of potential needs. Almost two thirds (65.6%) of the female patients and 10.9% of the males reported experiences of sexual violence. Victims differed from non-victims across a variety of domains, including more psychiatric symptoms and suicide attempts, more legal problems, financial and family problems, as well as a higher use of services. In contrast to a previous study among alcohol-dependent patients, no gender differences became apparent. Our findings suggest that experiences of sexual violence are an indicator for more complex needs in opioid-dependent patients of both genders. In addition to integrated trauma-informed approaches, an effort needs to be made to link addiction facilities to further institutions to meet these complex needs. Copyright © 2014 Elsevier Ltd. All rights reserved.

Extended Range of a Gun Launched Smart Projectile Using Controllable Canards

Directory of Open Access Journals (Sweden)

Mark Costello

2001-01-01

Full Text Available This effort investigates the extent to which moveable canards can extend the range of indirect fire munitions using both projectile body and canard lift. Implications on terminal velocity and time of flight using this mechanism to extend range are examined for various canard configurations. Performance predictions are conducted using a six-degree-of-freedom simulation model that has previously been validated against range data. The projectile dynamic equations are formed in the body frame and aerodynamic loads from the body and canards are Mach number and angle of attack dependent. The projectile body aerodynamic moments include unsteady aerodynamic damping. The focus of the study is directed toward low cost competent munitions that extend range and as such a simple flight control system is considered which utilizes only timer, roll rate, and roll attitude inputs.

An experimental study of dielectric dispersion in porous media and its dependence on pore geometry

Energy Technology Data Exchange (ETDEWEB)

Haslund, E.

1996-12-31

Understanding water saturated composite media are important in the study of oil reservoirs. This doctoral thesis discusses measurements of the frequency dependent permittivity and conductivity of water saturated porous glass specimens. The experiments are designed to investigate the dispersion resulting from the geometrical properties of the pore space. Measurements are presented of the effective complex dielectric constant of water saturated porous glass specimens for frequencies below 13 MHz. The specimens are made from sintered glass spheres, and in some specimens thin plates are mixed in with the spheres. Low-conductivity water is used to saturate the pore space in order to scale the frequency range of the Maxwell-Wagner dispersion into the measurement range. The experiments are compared with two different effective medium approaches. One approach is the Mendelson and Cohen theory with randomly oriented spheroidal grains in addition to spherical grains, the other the Local porosity theory due to Hilfer. Both theories were found to be in good agreement with the experimental observations. 175 refs., 59 figs., 1 table

Nuclear dynamics with the (finite range) Gogny force: flow effects

International Nuclear Information System (INIS)

Sebille, F.; Royer, G.; Schuck, P.; Gregoire, C.

1988-01-01

We introduce for the first time the effective finite range interaction of Gogny in the semi-classical description of heavy ion reactions based on the Landau-Vlasov equation. The characteristics of the flow for heavy ion collisions are studied as functions of the incident energy, the impact parameter and the mass number. The momentum dependence in the mean field together with the non linearities in the collision kernel decrease the flow in contradiction with other calculations; the origins of this discrepancy are studied in details

The refractive index of human hemoglobin in the visible range

International Nuclear Information System (INIS)

Zhernovaya, O; Tuchin, V; Sydoruk, O; Douplik, A

2011-01-01

Because the refractive index of hemoglobin in the visible range is sensitive to the hemoglobin concentration, optical investigations of hemoglobin are important for medical diagnostics and treatment. Direct measurements of the refractive index are, however, challenging; few such measurements have previously been reported, especially in a wide wavelength range. We directly measured the refractive index of human deoxygenated and oxygenated hemoglobin for nine wavelengths between 400 and 700 nm for the hemoglobin concentrations up to 140 g l -1 . This paper analyzes the results and suggests a set of model functions to calculate the refractive index depending on the concentration. At all wavelengths, the measured values of the refractive index depended on the concentration linearly. Analyzing the slope of the lines, we determined the specific refraction increments, derived a set of model functions for the refractive index depending on the concentration, and compared our results with those available in the literature. Based on the model functions, we further calculated the refractive index at the physiological concentration within the erythrocytes of 320 g l -1 . The results can be used to calculate the refractive index in the visible range for arbitrary concentrations provided that the refractive indices depend on the concentration linearly.

Reference Ranges in [(99m)Tc]Mercaptoacetyltriglycerine Renography

DEFF Research Database (Denmark)

Rewers, Kate I; Hvidsten, Svend; Gerke, Oke

2015-01-01

PURPOSE: The purpose of the study was to define reference ranges for quantitative parameters in [(99m)Tc]mercaptoacetyltriglycerine ([(99m)Tc]MAG3) renography to assist interpretation in a semi-automated (Xeleris, GE) compared to a manual (Picker, Odyssey) software package. PROCEDURES: Forty......-eight subjects approved for renal donation were evaluated with [(99m)Tc]MAG3 renography using both the Xeleris and the Picker software. RESULTS: Reference ranges for the two software were comparable regarding the relative function of the two kidneys (the split function, SF) and the residual activities (RA......). The time to peak whole-kidney activities (T max whole-kidney) was more dependent on the type of software. Using Bland-Altman limits, we found good and acceptable agreement between the two methods. CONCLUSIONS: We found good correlation between renography results using the Xeleris and Picker software...

Viability of long range dragonfly migration across the Indian Ocean: An energetics perspective

Science.gov (United States)

Saha, Sandeep; Nirwal, Satvik

2016-11-01

Recently Pantala flavescens (dragonflies) have been reported to migrate in millions from India to Eastern Africa on a multigenerational migratory circuit of length 14000-18000 kms. We attempt to understand the ability of dragonflies to perform long range migration by examining the energetics using computer simulations. In absence of a theory for long range insect migrations, we resort to the extensive literature on long range bird migration from the energetics perspective. The flight energetics depends upon instantaneous power and velocity. The mechanical flight power is computed from the power curve which is then converted to mass depletion using Brequet's equation. However, the mechanical flight power itself depends upon the instantaneous velocity which can vary depending upon the current mass. In order to predict the range in our simulations, we assume that the insect progressively tries to achieve the maximum range velocity. The results indicate that the migration range is approximately 1260 kms in 70 hours based on the true airspeed. However, our analysis is restricted by the lack of data and certain caveats in drag prediction and basal metabolism rate.

Study of excitation energy dependence of nuclear level density parameter

International Nuclear Information System (INIS)

Mohanto, G.; Nayak, B.K.; Saxena, A.

2016-01-01

In the present study, we have populated CN by fusion reaction and excitation energy of the intermediate nuclei is determined after first chance α-emission to investigate excitation energy dependence of the NLD parameter. Evaporated neutron spectra were measured following alpha evaporation for obtaining NLD parameter for the reaction 11 B + 197 Au, populating CN 208 Po. This CN after evaporating an α-particle populates intermediate nucleus 204 Pb. The 204 Pb has magic number of Z=82. Our aim is to study the excitation energy dependence of NLD parameter for closed shell nuclei

Population genetic analysis of Bromus tectorum (Poaceae) indicates recent range expansion may be facilitated by specialist genotypes

Science.gov (United States)

Keith R. Merrill; Susan E. Meyer; Craig E. Coleman

2012-01-01

The mechanisms for range expansion in invasive species depend on how genetic variation is structured in the introduced range. This study examined neutral genetic variation in the invasive annual grass Bromus tectorum in the Intermountain Western United States. Patterns of microsatellite (SSR) genotype distribution in this highly inbreeding species were used to make...

Theoretical and experimental study of AC electrical conduction mechanism in the low temperature range of p-CuIn3Se5

Science.gov (United States)

Essaleh, L.; Amhil, S.; Wasim, S. M.; Marín, G.; Choukri, E.; Hajji, L.

2018-05-01

In the present work, an attempt has been made to study theoretically and experimentally the AC electrical conduction mechanism in disordered semiconducting materials. The key parameter considered in this analysis is the frequency exponent s(ω , T) =( ∂ln(σAC(ω , T))/∂ ln(ω)T , where σAC is the AC electrical conductivity that depends on angular frequency ω and temperature T. In the theoretical part of this work, the effect of the barrier hopping energy, the polaron radius and the characteristic relaxation time is considered. The theoretical models of Quantum Mechanical Tunneling (QMT), Non overlapping Small Polaron Tunneling (NSPT), Overlapping Large Polaron Tunneling (OLPT) and Correlated Barrier Hopping (CBH) are considered to fit experimental data of σAC in p-CuIn3Se5 (p-CIS135) in the low temperature range up to 96 K. Some important parameters, as the polaron radius, the localization length and the barrier hopping energies, are estimated and their temperature and frequency dependence discussed.

Study on super-resolution three-dimensional range-gated imaging technology

Science.gov (United States)

Guo, Huichao; Sun, Huayan; Wang, Shuai; Fan, Youchen; Li, Yuanmiao

2018-04-01

Range-gated three dimensional imaging technology is a hotspot in recent years, because of the advantages of high spatial resolution, high range accuracy, long range, and simultaneous reflection of target reflectivity information. Based on the study of the principle of intensity-related method, this paper has carried out theoretical analysis and experimental research. The experimental system adopts the high power pulsed semiconductor laser as light source, gated ICCD as the imaging device, can realize the imaging depth and distance flexible adjustment to achieve different work mode. The imaging experiment of small imaging depth is carried out aiming at building 500m away, and 26 group images were obtained with distance step 1.5m. In this paper, the calculation method of 3D point cloud based on triangle method is analyzed, and 15m depth slice of the target 3D point cloud are obtained by using two frame images, the distance precision is better than 0.5m. The influence of signal to noise ratio, illumination uniformity and image brightness on distance accuracy are analyzed. Based on the comparison with the time-slicing method, a method for improving the linearity of point cloud is proposed.

Affective dependence and aggression: an exploratory study.

Science.gov (United States)

Petruccelli, Filippo; Diotaiuti, Pierluigi; Verrastro, Valeria; Petruccelli, Irene; Federico, Roberta; Martinotti, Giovanni; Fossati, Andrea; Di Giannantonio, Massimo; Janiri, Luigi

2014-01-01

Emotionally dependent subjects may engage in controlling, restrictive, and aggressive behaviours, which limit their partner's autonomy. The underlying causes of such behaviours are not solely based on levels of aggression, but act as a mean of maintaining the subject's own sense of self-worth, identity, and general functioning. The aim of the paper is to explore the correlation between affective dependency and reactive/proactive aggression and to evaluate individual differences as predisposing factors for aggressive behaviour and emotional dependency. The Spouse-Specific Dependency Scale (SSDS) and the Reactive Proactive Questionnaire (RPQ) were administered to a sample of 3375 subjects. In the whole sample, a positive correlation between emotional dependency and proactive aggression was identified. Differences with regard to sex, age group, and geographical distribution were evidenced for the scores of the different scales. A fundamental distinction between reactive and proactive aggression was observed, anchoring proactive aggression more strictly to emotional dependency. Sociocultural and demographical variables, together with the previous structuring of attachment styles, help to determine the scope, frequency, and intensity of the demands made to the partner, as well as to feed the fears of loss, abandonment, or betrayal.

Wide range neutron monitoring device

International Nuclear Information System (INIS)

Okido, Fumiyasu; Arita, Setsuo; Ishii, Kazuhiko; Matsumiya, Shoichi; Furusato, Ken-ichiro; Nishida, Akira.

1994-01-01

The present invention has a function of reliably switching measuring values between a pulse method and a Cambel method even if noise level and saturated level are fluctuated. That is, a proportional range judging means always monitors neutron flux measuring values in a start-up region and neutron flux measuring values in an intermediate power region, so that the proportional range is detected depending on whether the difference or a variation coefficient of both of the measured values is constant or not. A switching value determining means determines a switching value by the result of judgement of the proportional range judging means. A selection/output means selects and outputs measuring signals at a neutron flux level in the start-up region or the intermediate power region by the output of the switching value determining means. With such procedures, since the measuring value is switched after confirming that arrival at the proportional range where the difference or a variation coefficient of the measured value between the pulse processing method and the measured value by the Cambel method is constant, an accurate neutron flux level containing neither noise level nor saturated level can be outputted. (I.S.)

Transverse magneto-optical anisotropy in bidisperse ferrofluids with long range particle correlations

Energy Technology Data Exchange (ETDEWEB)

Elfimova, E.A.; Ivanov, A.O. [Ural Federal University, ul. Lenina 51, Yekaterinburg 620000 (Russian Federation); Popescu, L.B. [Institute for Space Sciences, Atomistilor 409, Magurele RO-077125 (Romania); Socoliuc, V., E-mail: vsocoliuc@acad-tim.tm.edu.ro [Romanian Academy-Timisoara Branch, Center for Fundamental and Advanced Technical Research, Lab. Magnetic Fluids, Bv.M. Viteazu 24, Timisoara RO-300223 (Romania)

2017-06-01

A comparative study between experiment and the predictions of a theoretical model developed for the description of magnetically induced dichroism in ferrofluids with long range interacting bidisperse spherical nanoparticles is presented. Magnetically induced dichroism in dilution series of two ferrofluids with different surfactant thickness was measured. Both ferrofluids show a concave solid volume fraction dependence of the specific dichroism, whose characteristics are very well qualitatively explained by the theoretical model. The theory fails to satisfactorily explain the magnetic field dependence of the highly concentrated samples specific dichroism, due to inherent approximations in the virial expansion of the pair correlation function.

Study of identification of geometrically shaped solids using colour and range information

International Nuclear Information System (INIS)

Ebihara, Kenichi

1997-05-01

This report is the revision of the Technical Report (MECSE 1996-7) of Monash University in Melbourne, Australia which has been distributed to the Department Library in this University. The main work which is described in this report was carried out at Intelligent Robotics Research Center (IRRC) in the Department of Electrical and Computer Systems Engineering of Monash University from March in 1995 to March in 1996 and was be supported by a grant from Research Development Corporation of Japan (JRDC). This report describes the study of identification of geometrically shaped solids with unique colour using colour and range information. This study aims at recognition of equipment in nuclear plants. For this purpose, it is hypothesized that equipment in nuclear plants can be represented by combination of geometrically shaped solids with unique colour, such as a sphere, an ellipsoid, a cone, a cylinder, a rectangular solid and a pyramid. In this report, the colour image of geometrically shaped solids could be segmented comparatively easily and effectively into regions of each solid by using colour and range information. The range data of each solid was extracted using the segmented colour image. Thus the extracted range data could be classified into a plane surface or a curved surface by checking its spatial distribution. (author)

Temperature-dependent μ-Raman investigation of struvite crystals.

Science.gov (United States)

Prywer, Jolanta; Kasprowicz, D; Runka, T

2016-04-05

The effect of temperature on the vibrational properties of struvite crystals grown from silica gels was systematically studied by μ-Raman spectroscopy. The time-dependent Raman spectra recorded in the process of long time annealing of struvite crystal at 353 K do not indicate structural changes in the struvite crystal with the time of annealing. The temperature-dependent Raman spectra recorded in the range 298-423 K reveal a phase transition in struvite at about 368 K. Above this characteristic temperature, some of bands assigned to vibrations of the PO4 and NH4 tetrahedra and water molecules observed in the Raman spectra in low temperatures (orthorhombic phase) change their spectral parameters or disappear, which indicates a transition to a higher symmetry structure of struvite in the range of high temperatures. Copyright © 2016 Elsevier B.V. All rights reserved.

Mental Disorders in Substance Dependent Individuals as Compared to Non-Substance Dependent People in Hamadan, Iran

Directory of Open Access Journals (Sweden)

A. Heidari Pahlavian

2011-10-01

Full Text Available Introduction & Objective: There are several close links between substance dependency and mental disorders. Many people who regularly abuse drugs are also diagnosed with psychiatric disorders and vice versa. The high prevalence of this comorbidity has been documented in several studies, although most of the research has been carried out in only a few countries and the cultural validity of the data is unknown. Thus the aim of this study was the comparative investigation of mental disorders in drug dependent and non drug dependent persons in city of Hamadan.Materials & Methods: This study was a descriptive comparative research. 106 men aged 18 to 51 who sought treatment at addiction rehabilitation department of Hamadan were recruited in this study. Also 106 men in the same age range were matched with the first group. Data were collected through structured clinical interview for DSM-IV-TR and SCL 90-R questionnaire. Data were analyzed using t-test and correlation coefficient test.Results: The rate and severity of mental disorders in 9 studied Categories of disorders—phobia, anxiety, somatization, psychotism, depression, paranoid thoughts, aggression, interpersonal sensitivity and obsession-compulsion—were significantly higher among the addicts than the normal group.The level of severity was higher in depression, paranoid thoughts and interpersonal sensitivity than the other disorders. 63.5% of addicts suffered from some psychological disorders while the figures for no addicts were 28.8%. The prevalence of co-morbid psychiatric disorders varied with the pattern of addicts.Conclusion: This study showed that persons with substance dependence display more signs of psycho pathology and mental disorders in comparison with non- substance dependent people.(Sci J Hamadan Univ Med Sci 2011;18(3:22-28

Age at onset typology in opioid dependent men: an exploratory study.

Science.gov (United States)

De, Biswajit; Mattoo, Surendra K; Basu, Debasish

2002-04-01

This study attempted to apply age at onset typology in ICD-10 diagnosed opioid dependence. The sample comprised 80 men seeking treatment at an addiction clinic. The measures included socio-demographic and clinical profile, Severity of Opioid Dependence Questionnaire, Modified Sensation Seeking Scale, Multiphasic Personality Questionnaire (MPQ) and Family History Assessment Module. A cut-off age of 20/21 years for an early-onset late-onset typology of opioid dependence was obtained using two methods - the modal age at onset method and one-third sample by age at onset method. The early onset group showed significant differences in terms of it being more often younger, urban, unmarried, wage earning or students, using oral opioids (not heroin or injectables), showing higher lifetime use and dependence of sedatives, earlier onset of use and dependence of sedatives and tobacco, and higher global psychopathology in terms of MPQ. The early onset group also showed statistically insignificant trends for lesser use and dependence of alcohol, higher severity of opioid dependence, more legal and less social complications, higher sensation seeking (except boredom susceptibility), and more frequent substance dependence in first degree relatives. The age at onset typology in opioid dependence appears to be feasible and having some similarities to similar typology in alcoholism.

Density-dependent electron scattering in photoexcited GaAs

DEFF Research Database (Denmark)

Mics, Zoltán; D'’Angio, Andrea; Jensen, Søren A.

2013-01-01

—In a series of systematic optical pump - terahertz probe experiments we study the density-dependent electron scattering rate in photoexcited GaAs in a large range of carrier densities. The electron scattering time decreases by as much as a factor of 4, from 320 to 60 fs, as the electron density...

A swinging seesaw as a novel model mechanism for time-dependent hormesis under dose-dependent stimulatory and inhibitory effects: A case study on the toxicity of antibacterial chemicals to Aliivibrio fischeri.

Science.gov (United States)

Sun, Haoyu; Calabrese, Edward J; Zheng, Min; Wang, Dali; Pan, Yongzheng; Lin, Zhifen; Liu, Ying

2018-08-01

Hormesis occurs frequently in broadly ranging biological areas (e.g. plant biology, microbiology, biogerontology), toxicology, pharmacology and medicine. While numerous mechanisms (e.g. receptor and pathway mediated pathway responses) account for stimulatory and inhibitory features of hormetic dose responses, the vast majority emphasizes the inclusion of many doses but only one timepoint or use of a single optimized dose that is assessed over a broad range of timepoints. In this paper, a toxicity study was designed using a large number of properly spaced doses with responses determined over a large number of timepoints, which could help us reveal the underlying mechanism of hormesis. We present the results of a dose-time-response study on hormesis using five antibacterial chemicals on the bioluminescence of Aliivibrio fischeri, measuring expression of protein mRNA based on quorum sensing, simulating bioluminescent reaction and analyzing toxic actions of test chemicals. The findings show dose-time-dependent responses conforming to the hormetic dose-response model, while revealing unique response dynamics between agent induced stimulatory and inhibitory effects within bacterial growth phase dynamics. These dynamic dose-time features reveal a type of biological seesaw model that integrates stimulatory and inhibitory responses within unique growth phase, dose and time features, which has faultlessly explained the time-dependent hormetic phenomenon induced by five antibacterial chemicals (characterized by low-dose stimulation and high-dose inhibition). This study offers advances in understanding cellular dynamics, the biological integration of diverse and opposing responses and their role in evolutionary adaptive strategies to chemicals, which can provide new insight into the mechanistic investigation of hormesis. Copyright © 2018 Elsevier Ltd. All rights reserved.

Affective Dependence and Aggression: An Exploratory Study

Directory of Open Access Journals (Sweden)

Filippo Petruccelli

2014-01-01

Full Text Available Introduction. Emotionally dependent subjects may engage in controlling, restrictive, and aggressive behaviours, which limit their partner’s autonomy. The underlying causes of such behaviours are not solely based on levels of aggression, but act as a mean of maintaining the subject’s own sense of self-worth, identity, and general functioning. Objective. The aim of the paper is to explore the correlation between affective dependency and reactive/proactive aggression and to evaluate individual differences as predisposing factors for aggressive behaviour and emotional dependency. Methods. The Spouse-Specific Dependency Scale (SSDS and the Reactive Proactive Questionnaire (RPQ were administered to a sample of 3375 subjects. Results. In the whole sample, a positive correlation between emotional dependency and proactive aggression was identified. Differences with regard to sex, age group, and geographical distribution were evidenced for the scores of the different scales. Conclusion. A fundamental distinction between reactive and proactive aggression was observed, anchoring proactive aggression more strictly to emotional dependency. Sociocultural and demographical variables, together with the previous structuring of attachment styles, help to determine the scope, frequency, and intensity of the demands made to the partner, as well as to feed the fears of loss, abandonment, or betrayal.

Does the care dependency of nursing home residents influence their health-related quality of life?-A cross-sectional study.

Science.gov (United States)

Tabali, Manuela; Ostermann, Thomas; Jeschke, Elke; Dassen, Theo; Heinze, Cornelia

2013-03-11

Studies on health-related quality of life (HRQOL) are missing for nursing home residents independent from their health conditions or interventions after admission. Our aim was to analyse if the care dependency of nursing home residents influence their HRQOL and to describe HRQOL of nursing home residents at the time of admission. Eleven German nursing homes were randomly selected for a cross-sectional multicentre study from April 2008 until December 2009. HRQOL was measured with the Nottingham Health Profile (NHP) in the six domains "Physical Mobility", "Energy", "Pain", "Social Isolation", "Emotional Reaction" and "Sleep". Domain scores range from zero (good subjective health status) to 100 (poor subjective health status). Care dependency was evaluated using the Care Dependency Scale, age, sex, cognitive status and diseases were documented by the research assistants. Multivariate regression analysis was performed to quantify the influence of care dependency on HRQOL. 120 residents were included in total. HRQOL was mostly reduced in the domains "Physical Mobility" and "Energy" (mean scores >43.0), while impairment differences in the domains "Pain", "Social Isolation", "Emotional Reaction" and "Sleep" were only moderate (≤25.0). HRQOL was not influenced by the age. Women (n = 85) had a significantly poorer HRQOL in the domain "Pain" than men (mean score women: 29.5 ± 31.5; males: 14.9 ± 17.2; p = 0.011). Care dependency had an influence on the domain "Sleep" (ß = -0.195, p = 0.031), while the other domains were not influenced by care dependency. Residents with a low care dependency scored significantly lower (better HRQOL) in the domain "Sleep" than residents with a high care dependency (mean score 15.3; SD ± 19.0 versus mean score 32.8 SD ± 33.2; p dependency has no influence on the HRQOL from the nursing home residents' perspective apart from the domain "Sleep". High care dependency residents have a lower HRQOL in the

A multiwell platform for studying stiffness-dependent cell biology.

Science.gov (United States)

Mih, Justin D; Sharif, Asma S; Liu, Fei; Marinkovic, Aleksandar; Symer, Matthew M; Tschumperlin, Daniel J

2011-01-01

Adherent cells are typically cultured on rigid substrates that are orders of magnitude stiffer than their tissue of origin. Here, we describe a method to rapidly fabricate 96 and 384 well platforms for routine screening of cells in tissue-relevant stiffness contexts. Briefly, polyacrylamide (PA) hydrogels are cast in glass-bottom plates, functionalized with collagen, and sterilized for cell culture. The Young's modulus of each substrate can be specified from 0.3 to 55 kPa, with collagen surface density held constant over the stiffness range. Using automated fluorescence microscopy, we captured the morphological variations of 7 cell types cultured across a physiological range of stiffness within a 384 well plate. We performed assays of cell number, proliferation, and apoptosis in 96 wells and resolved distinct profiles of cell growth as a function of stiffness among primary and immortalized cell lines. We found that the stiffness-dependent growth of normal human lung fibroblasts is largely invariant with collagen density, and that differences in their accumulation are amplified by increasing serum concentration. Further, we performed a screen of 18 bioactive small molecules and identified compounds with enhanced or reduced effects on soft versus rigid substrates, including blebbistatin, which abolished the suppression of lung fibroblast growth at 1 kPa. The ability to deploy PA gels in multiwell plates for high throughput analysis of cells in tissue-relevant environments opens new opportunities for the discovery of cellular responses that operate in specific stiffness regimes.

A multiwell platform for studying stiffness-dependent cell biology.

Directory of Open Access Journals (Sweden)

Justin D Mih

Full Text Available Adherent cells are typically cultured on rigid substrates that are orders of magnitude stiffer than their tissue of origin. Here, we describe a method to rapidly fabricate 96 and 384 well platforms for routine screening of cells in tissue-relevant stiffness contexts. Briefly, polyacrylamide (PA hydrogels are cast in glass-bottom plates, functionalized with collagen, and sterilized for cell culture. The Young's modulus of each substrate can be specified from 0.3 to 55 kPa, with collagen surface density held constant over the stiffness range. Using automated fluorescence microscopy, we captured the morphological variations of 7 cell types cultured across a physiological range of stiffness within a 384 well plate. We performed assays of cell number, proliferation, and apoptosis in 96 wells and resolved distinct profiles of cell growth as a function of stiffness among primary and immortalized cell lines. We found that the stiffness-dependent growth of normal human lung fibroblasts is largely invariant with collagen density, and that differences in their accumulation are amplified by increasing serum concentration. Further, we performed a screen of 18 bioactive small molecules and identified compounds with enhanced or reduced effects on soft versus rigid substrates, including blebbistatin, which abolished the suppression of lung fibroblast growth at 1 kPa. The ability to deploy PA gels in multiwell plates for high throughput analysis of cells in tissue-relevant environments opens new opportunities for the discovery of cellular responses that operate in specific stiffness regimes.

Dependence of a class of non-integer power functions

Directory of Open Access Journals (Sweden)

Ming Li

2016-10-01

Full Text Available This short article exhibits that there exists critical point of the power for the generalized function t-a for a > 0. The present results show that it is long-range dependent if 0  1. My motivation of studying that dependence issue comes from the power-law type functions in fractal time series. The present results may yet be useful to investigate fractal behavior of fractal time series from a new point of view.

Ranging Behaviour of Commercial Free-Range Broiler Chickens 2: Individual Variation.

Science.gov (United States)

Taylor, Peta S; Hemsworth, Paul H; Groves, Peter J; Gebhardt-Henrich, Sabine G; Rault, Jean-Loup

2017-07-20

Little is known about broiler chicken ranging behaviour. Previous studies have monitored ranging behaviour at flock level but whether individual ranging behaviour varies within a flock is unknown. Using Radio Frequency Identification technology, we tracked 1200 individual ROSS 308 broiler chickens across four mixed sex flocks in two seasons on one commercial farm. Ranging behaviour was tracked from first day of range access (21 days of age) until 35 days of age in winter flocks and 44 days of age in summer flocks. We identified groups of chickens that differed in frequency of range visits: chickens that never accessed the range (13 to 67% of tagged chickens), low ranging chickens (15 to 44% of tagged chickens) that accounted for range visits and included chickens that used the range only once (6 to 12% of tagged chickens), and high ranging chickens (3 to 9% of tagged chickens) that accounted for 33 to 50% of all range visits. Males spent longer on the range than females in winter ( p ranging behaviour may help optimise ranging opportunities in free-range systems and is important to elucidate the potential welfare implications of ranging.

Semi-empirical calculations for the ranges of fast ions in silicon

Science.gov (United States)

Belkova, Yu. A.; Teplova, Ya. A.

2018-04-01

A semi-empirical method is proposed to calculate the ion ranges in energy region E = 0.025-10 MeV/nucleon. The dependence of ion ranges on the projectile nuclear charge, mass and velocity is analysed. The calculations presented for ranges of ions with nuclear charges Z = 2-10 in silicon are compared with SRIM results and experimental data.

Ranging Behaviour of Commercial Free-Range Laying Hens.

Science.gov (United States)

Chielo, Leonard Ikenna; Pike, Tom; Cooper, Jonathan

2016-04-26

In this study, the range use and behaviour of laying hens in commercial free-range flocks was explored. Six flocks were each visited on four separate days and data collected from their outdoor area (divided into zones based on distance from shed and available resources). These were: apron (0-10 m from shed normally without cover or other enrichments); enriched belt (10-50 m from shed where resources such as manmade cover, saplings and dust baths were provided); and outer range (beyond 50 m from shed with no cover and mainly grass pasture). Data collection consisted of counting the number of hens in each zone and recording behaviour, feather condition and nearest neighbour distance (NND) of 20 birds per zone on each visit day. In addition, we used techniques derived from ecological surveys to establish four transects perpendicular to the shed, running through the apron, enriched belt and outer range. Number of hens in each 10 m × 10 m quadrat was recorded four times per day as was the temperature and relative humidity of the outer range. On average, 12.5% of hens were found outside. Of these, 5.4% were found in the apron; 4.3% in the enriched zone; and 2.8% were in the outer range. This pattern was supported by data from quadrats, where the density of hens sharply dropped with increasing distance from shed. Consequently, NND was greatest in the outer range, least in the apron and intermediate in the enriched belt. Hens sampled in outer range and enriched belts had better feather condition than those from the apron. Standing, ground pecking, walking and foraging were the most commonly recorded activities with standing and pecking most likely to occur in the apron, and walking and foraging more common in the outer range. Use of the outer range declined with lower temperatures and increasing relative humidity, though use of apron and enriched belt was not affected by variation in these measures. These data support previous findings that outer range areas tend to be

Analysis of (d,n) reactions via the Dirac DWBA with finite range

Science.gov (United States)

Hawk, Eric; McNeil, J. A.

2004-10-01

The Distorted-wave Born Approximation (DWBA) is used to calculate differential cross sections of low-energy deuteron stripping reactions. The implementation makes use of Dirac phenomenological potentials with an exact treatment of finite-range effects. The mutual interaction of these effects upon the resulting calculations will be presented. In addition, we use our finite-range implementation to study the effect on the cross sections due to the model dependence of the internal deuteron wave function. Specifically, we examine this effect using the internal deuteron wave functions generated with the Reid soft-core, Bonn, and Argonne-V18 potentials.

Long-range interaction between spins

International Nuclear Information System (INIS)

Naik, P.C.; Pradhan, T.

1981-01-01

It is shown that invariance of Lagrangian field theory under a class of the coordinate-dependent Lorentz group of transformations requires the introduction of a massless axial vector gauge field which gives rise to a super-weak long-range spin-spin force between particles in vacuum. Recent experiments demonstrating repulsion and attraction between circularly polarised laser beams are interpreted to be due to such a force enhanced by spin polarisation of sodium vapour, through which these beams pass. (author)

Consistency-dependent optical properties of lubricating grease studied by terahertz spectroscopy

International Nuclear Information System (INIS)

Tian Lu; Zhao Kun; Zhou Qing-Li; Shi Yu-Lei; Zhao Dong-Mei; Zhang Cun-Lin; Zhao Song-Qing; Zhao Hui; Bao Ri-Ma; Zhu Shou-Ming; Miao Qing

2011-01-01

The optical properties of four kinds of lubricating greases (urea, lithium, extreme pressure lithium, molybdenum disulfide lithium greases) with different NLGL (National Lubricant Grease Institute of America) numbers were investigated using terahertz time-domain spectroscopy. Greases with different NLGL grades have unique spectral features in the terahertz range. Comparison of the experimental data with predictions based on Lorentz—Lorenz theory exhibited that the refractive indices of each kind of lubricating grease were dependent on the their consistency. In addition, molybdenum disulfide (MoS 2 ) as a libricant additive shows strong absorption from 0.2 to 1.4 THz, leading to higher absorption of MoS 2 -lithium grease than that of lithium grease. (general)

Length dependent properties of SNS microbridges

International Nuclear Information System (INIS)

Sauvageau, J.E.; Jain, R.K.; Li, K.; Lukens, J.E.; Ono, R.H.

1985-01-01

Using an in-situ, self-aligned deposition scheme, arrays of variable length SNS junctions in the range of 0.05 μm to 1 μm have been fabricated. Arrays of SNS microbridges of lead-copper and niobium-copper fabricated using this technique have been used to study the length dependence, at constant temperature, of the critical current I and bridge resistance R /SUB d/ . For bridges with lengths pounds greater than the normal metal coherence length xi /SUB n/ (T), the dependence of I /SUB c/ on L is consistent with an exponential dependence on the reduced length l=L/xi /SUB n/ (T). For shorter bridges, deviations from this behavior is seen. It was also found that the bridge resistance R /SUB d/ does not vary linearly with the geometric bridge length but appears to approach a finite value as L→O

Winter Precipitation Efficiency of Mountain Ranges in the Colorado Rockies Under Climate Change

Science.gov (United States)

Eidhammer, Trude; Grubišić, Vanda; Rasmussen, Roy; Ikdea, Kyoko

2018-03-01

Orographic precipitation depends on the environmental conditions and the barrier shape. In this study we examine the sensitivity of the precipitation efficiency (i.e., drying ratio (DR)), defined as the ratio of precipitation to incoming water flux, to mountain shape, temperature, stability, and horizontal velocity of the incoming air mass. Furthermore, we explore how the DR of Colorado mountain ranges might change under warmer and moister conditions in the future. For given environmental conditions, we find the DR to be primarily dependent on the upwind slope for mountain ranges wider than about 70 km and on both the slope and width for narrower ranges. Temperature is found to exert an influence on the DR for all Colorado mountain ranges, with DR decreasing with increasing temperature, under both the current and future climate conditions. The decrease of DR with temperature under warmer climate was found to be stronger for wider mountains than the narrower ones. We attribute this asymmetry to the sensitivity of DR to reduced horizontal velocity under warmer conditions. Specifically, while DR for wider mountains shows no sensitivity to changes in horizontal velocity, the DR for narrow ranges increases as the horizontal velocity decreases and more time is provided for precipitation to form. Thus, for narrower ranges, the horizontal velocity appears to offset the temperature effect slightly. The percentagewise decrease of DR for all examined mountain ranges is about 4%K-1. In comparison, the increase in precipitation is about 6%K-1 while the vapor flux increase is about 9%K-1.

On Dynamic Range Limitations of CMOS Current Conveyors

DEFF Research Database (Denmark)

Bruun, Erik

1999-01-01

frequency band and for the situation where the conveyor is used over the full bandwidth achievable. Finally, the optimisation of the current input range is related to the distortion characteristics and it is pointed out that to a first order approximation the distortion is independent of the current range.......This paper is concerned with the dynamic range of continuous time CMOS current mode circuits. As a representative current mode device a class AB current conveyor is examined. First, the voltage input range of the high impedance Y input is investigated. Next, the current input range of the low...... impedance X input is investigated. It is compared to the thermal noise in the X to Z signal path in order to evaluate the dynamic range, and the dependencies of the dynamic range on the supply voltage and the transistor lay-out is derived, both for the situation where the conveyor is used over a narrow...

Range and Endurance Tradeoffs on Personal Rotorcraft Design

Science.gov (United States)

Snyder, Christopher A.

2016-01-01

Rotorcraft design has always been a challenging tradeoff among overall size, capabilities, complexity, and other factors based on available technology and customer requirements. Advancements in propulsion, energy systems and other technologies have enabled new vehicles and missions; complementary advances in analysis methods and tools enable exploration of these enhanced vehicles and the evolving mission design space. A system study was performed to better understand the interdependency between vehicle design and propulsion system capabilities versus hover / loiter requirements and range capability. Three representative vertical lift vehicles were developed to explore the tradeoff in capability between hover efficiency versus range and endurance capability. The vehicles were a single-main rotor helicopter, a tilt rotor, and a vertical take-off and landing (VTOL) aircraft. Vehicle capability was limited to two or three people (including pilot or crew) and maximum range within one hour of flight (100-200 miles, depending on vehicle). Two types of propulsion and energy storage systems were used in this study. First was traditional hydrocarbon-fueled cycles (such as Otto, diesel or gas turbine cycles). Second was an all-electric system using electric motors, power management and distribution, assuming batteries for energy storage, with the possibility of hydrocarbon-fueled range extenders. The high power requirements for hover significantly reduced mission radius capability. Loiter was less power intensive, resulting in about 1/2 the equivalent mission radius penalty. With so many design variables, the VTOL aircraft has the potential to perform well for a variety of missions. This vehicle is a good candidate for additional study; component model development is also required to adequately assess performance over the design space of interest.

Temperature dependent charge transport in poly(3-hexylthiophene) diodes

Science.gov (United States)

Rahaman, Abdulla Bin; Sarkar, Atri; Banerjee, Debamalya

2018-04-01

In this work, we present charge transport properties of poly(3-hexylthiophene) (P3HT) diodes under dark conditions. Temperature dependent current-voltage (J-V) characteristics shows that charge transport represents a transition from ohomic to trap limited current. The forward current density obeys a power law J˜Vm, m>2 represents the space charge limited current region in presence of traps within the band gap. Frequency dependent conductivity has been studied in a temperature range 150K-473K. The dc conductivity values show Arrhenius like behavior and it gives conductivity activation energy 223 meV. Temperature dependent conductivity indicates a thermodynamic transition of our system.

Theoretical study of temperature dependent acoustic attenuation and non-linearity parameters in alkali metal hydride and deuteride

Energy Technology Data Exchange (ETDEWEB)

Singh, Rishi Pal [Department of Physics, Banaras Hindu University, Varanasi 221005 (India); Singh, Rajendra Kumar, E-mail: rksingh_17@rediffmail.com [Department of Physics, Banaras Hindu University, Varanasi 221005 (India)

2010-11-01

Temperature dependence of acoustic attenuation and non-linearity parameters in lithium hydride and lithium deuteride have been studied for longitudinal and shear modes along various crystallographic directions of propagation in a wide temperature range. Lattice parameter and repulsive parameters have been used as input data and interactions up to next nearest neighbours have been considered to calculate second and third order elastic constants which in turn have been used for evaluating acoustic attenuation and related parameters. The results have been discussed and compared with available data. It is hoped that the present results will serve to stimulate the determination of the acoustic attenuation of these compounds at different temperatures.

Crossed beam study of He+-O2 charge transfer reactions in the collision energy range 0.5-200 eV

International Nuclear Information System (INIS)

Bischof, G.; Linder, F.

1986-01-01

Energy spectra and angular distributions of the O + and O 2 + product ions resulting from the He + -O 2 charge transfer reaction have been measured in the collision energy range 0.5-200 eV using the crossed-beam method. The O 2 + ions represent only a minor fraction of the reaction products (0.2-0.6% over the energy range measured). In the dissociative charge transfer reaction, four main processes are identified leading to O+O + reaction products in different electronic states. Two different mechanisms can be distinguished, each being responsible for two of the observed processes: (i) a long-distance energy-resonant charge transfer process involving the c 4 Σsub(u) - (upsilon'=0) state of O 2 + and (ii) a slightly exothermic charge transfer process via the (III) 2 PIsub(u) state of O 2 + (with the exothermicity depending on the collision energy). Angle-integrated branching ratios and partial cross sections (in absolute units) have been determined. The branching ratios of the individual processes show a pronounced dependence on the collision energy. At low energies, the O + product ions are preferentially formed in the 2 P 0 and 2 D 0 excited states. The angular distributions of the O + product ions show an anisotropic behaviour indicating an orientation-dependent charge transfer probability in the He + -O 2 reaction. (orig.)

Description of plasmon-like band in silver clusters: the importance of the long-range Hartree-Fock exchange in time-dependent density-functional theory simulations.

Science.gov (United States)

Rabilloud, Franck

2014-10-14

Absorption spectra of Ag20 and Ag55(q) (q = +1, -3) nanoclusters are investigated in the framework of the time-dependent density functional theory in order to analyse the role of the d electrons in plasmon-like band of silver clusters. The description of the plasmon-like band from calculations using density functionals containing an amount of Hartree-Fock exchange at long range, namely, hybrid and range-separated hybrid (RSH) density functionals, is in good agreement with the classical interpretation of the plasmon-like structure as a collective excitation of valence s-electrons. In contrast, using local or semi-local exchange functionals (generalized gradient approximations (GGAs) or meta-GGAs) leads to a strong overestimation of the role of d electrons in the plasmon-like band. The semi-local asymptotically corrected model potentials also describe the plasmon as mainly associated to d electrons, though calculated spectra are in fairly good agreement with those calculated using the RSH scheme. Our analysis shows that a portion of non-local exchange modifies the description of the plasmon-like band.

Demonstrator study for micro-ranging-laser device

Science.gov (United States)

Henkel, Hartmut; Bernhardt, Bodo; Pereira do Carmo, J.

2017-11-01

Within ESA's Innovation Triangle Initiative (ITI) a demonstrator breadboard for a micro-ranging-laser device "MYLRAD" has been developed. Its working principle is the measurement of the round-trip delay time of a laser beam as a phase shift. The demonstrator consists of the laser diode (30 mW, square wave AM), optics, APD detector, narrowband preamplifier, limiter, and a phase digitiser based on a novel noise-shaping synchroniser (NSS) circuit; this works without ADCs and can be built from rad-hard components for space. The system timing and the digitiser algorithm are performed by an FPGA. The demonstrator has been tested at ranges from 1 m to 30 m. With a static non-cooperative target an RMS noise of 1 mm at a result rate of 60 Hz was reached. The demonstrator needs less than 2.5 W power.

NEAs: Phase Angle Dependence of Asteroid Class and Diameter from Observational Studies

Science.gov (United States)

Wooden, Diane H.; Lederer, Susan M.; Bus, Schlete; Tokunaga, Alan; Jehin, Emmanuel; Howell, Ellen S.; Nolan, Michael C.; Ryan, Erin; Fernandez, Yan; Harker, David;

Long-range interaction of anisotropic systems

KAUST Repository

Zhang, Junyi

2015-02-01

The first-order electrostatic interaction energy between two far-apart anisotropic atoms depends not only on the distance between them but also on their relative orientation, according to Rayleigh-Schrödinger perturbation theory. Using the first-order interaction energy and the continuum model, we study the long-range interaction between a pair of parallel pristine graphene sheets at zero temperature. The asymptotic form of the obtained potential density, &epsi:(D) &prop: ?D ?3 ?O(D?4), is consistent with the random phase approximation and Lifshitz theory. Accordingly, neglectance of the anisotropy, especially the nonzero first-order interaction energy, is the reason why the widely used Lennard-Jones potential approach and dispersion corrections in density functional theory give a wrong asymptotic form ε(D) &prop: ?D?4. © EPLA, 2015.

Long-range interaction of anisotropic systems

KAUST Repository

Zhang, Junyi; Schwingenschlö gl, Udo

2015-01-01

The first-order electrostatic interaction energy between two far-apart anisotropic atoms depends not only on the distance between them but also on their relative orientation, according to Rayleigh-Schrödinger perturbation theory. Using the first-order interaction energy and the continuum model, we study the long-range interaction between a pair of parallel pristine graphene sheets at zero temperature. The asymptotic form of the obtained potential density, &epsi:(D) &prop: ?D ?3 ?O(D?4), is consistent with the random phase approximation and Lifshitz theory. Accordingly, neglectance of the anisotropy, especially the nonzero first-order interaction energy, is the reason why the widely used Lennard-Jones potential approach and dispersion corrections in density functional theory give a wrong asymptotic form ε(D) &prop: ?D?4. © EPLA, 2015.

Dependence of hydrogen arcjet operation on electrode geometry

Science.gov (United States)

Pencil, Eric J.; Sankovic, John M.; Sarmiento, Charles J.; Hamley, John A.

1992-01-01

The dependence of 2 kW hydrogen arcjet performance on cathode to anode electrode spacing was evaluated at specific impulses of 900 and 1000 s. Less than 2 absolute percent change in efficiency was measured for the spacings tested which did not repeat the 14 absolute percent variation reported in earlier work with similar electrode designs. A different nozzle configuration was used to quantify the variation in hydrogen arcjet performance over an extended range of electrode spacing. Electrode gap variation resulted in less than 3 absolute percent change in efficiency. These null results suggested that electrode spacing is decoupled from hydrogen arcjet performance considerations over the ranges tested. Initial studies were conducted on hydrogen arcjet ignition. The dependence of breakdown voltage on mass flow rate and hydrogen arcjet ignition on rates of pulse repetition and pulse voltage rise were also included for comparison with previous results obtained using simulated hydrazine.

Load dependency in force-length relations in isolated single cardiomyocytes.

Science.gov (United States)

Iribe, Gentaro; Kaneko, Toshiyuki; Yamaguchi, Yohei; Naruse, Keiji

2014-08-01

The previously reported pressure-volume (PV) relationship in frog hearts shows that end-systolic PV relation (ESPVR) is load dependent, whereas ESPVR in canine hearts is load independent. To study intrinsic cardiac mechanics in detail, it is desirable to study mechanics in a single isolated cardiomyocyte that is free from interstitial connective tissue. Previous single cell mechanics studies used a pair of carbon fibers (CF) attached to the upper surface of opposite cell ends to stretch cells. These studies showed that end-systolic force-length (FL) relation (ESFLR) is load independent. However, the range of applicable mechanical load using the conventional technique is limited because of weak cell-CF attachment. Therefore, the behavior of ESFLR in single cells under physiologically possible conditions of greater load is not yet well known. To cover wider loading range, we contrived a new method to hold cell-ends more firmly using two pairs of CF attached to both upper and bottom surfaces of cells. The new method allowed stretching cells to 2.2 μm or more in end-diastolic sarcomere length. ESFLR virtually behaves in a load independent manner only with end-diastolic sarcomere length less than 1.95 μm. It exhibited clear load dependency with higher preload, especially with low afterload conditions. Instantaneous cellular elastance curves showed that decreasing afterload enhanced relaxation and slowed time to peak elastance, as previously reported. A simulation study of a mathematical model with detailed description of thin filament activation suggested that velocity dependent thin filament inactivation is crucial for the observed load dependent behaviors and previously reported afterload dependent change in Ca(2+) transient shape. Copyright © 2014 Elsevier Ltd. All rights reserved.

Emotion-Cognition Interactions; A Study on Coping Responses of Methamphetamine Dependent Women

Directory of Open Access Journals (Sweden)

Zahra Alam Mehrjerdi

2011-09-01

Full Text Available Introduction: Coping responses are complex dynamic behavioral reactions that involve reciprocal influences between emotion and cognition but cognitive studies in Iran have less emphasized coping responses of methamphetamine dependent individuals to distressing situations. To address this aim, the current study was designed to investigate the coping responses of a group of methamphetamine dependent women in comparison with a group of healthy women. Methods: 80 women with mean age 24(SD=6.8 years who met DSM.IV-TR criteria for methamphetamine dependence were recruited from the department of psychostimulant use treatment program of Rojan psychiatric center and 4 other local clinics in Tehran, Iran and were matched with a sample of 80 non-drug taking women. First, demographics and details of substance use were completed based on items elicited from Addiction Severity Index (ASI, then the Persian version of Billings and Moos Coping Checklist was completed by participants in each group. Data was further analyzed by performing independent sample t-test and logistic regression model in SPSS.v.16.0. Results: The study findings indicated that the methamphetamine dependent group applied less problem-solving response and had lower reliance on seeking social support and cognitive evaluation compared with the controls. In addition, the methamphetamine dependent group applied significantly more emotional and physical control oriented responses compared with the controls. Discussion: The study results yielded that coping responses of the methamphetamine dependent group were less problem-focused strategies which show an impaired aspect of cognitive functioning which is subject to clinical and treatment implications. Study in the context of identifying aspects that are fundamental to understanding the neural mechanisms underlying emotion-cognition interactions in the paradigm of coping responses is discussed.

Emotion-Cognition Interactions A Study on Coping Responses of Methamphetamine Dependent Women

Directory of Open Access Journals (Sweden)

Zahra Alam Mehrjerdi

2011-09-01

Full Text Available Introduction: Coping responses are complex dynamic behavioral reactions that involve reciprocal influences between emotion and cognition but cognitive studies in Iran have less emphasized coping responses of methamphetamine dependent individuals to distressing situations. To address this aim, the current study was designed to investigate the coping responses of a group of methamphetamine dependent women in comparison with a group of healthy women. Methods: 80 women with mean age 24(SD=6.8 years who met DSM.IV-TR criteria for methamphetamine dependence were recruited from the department of psychostimulant use treatment program of Rojan psychiatric center and 4 other local clinics in Tehran, Iran and were matched with a sample of 80 non-drug taking women. First, demographics and details of substance use were completed based on items elicited from Addiction Severity Index (ASI, then the Persian version of Billings and Moos Coping Checklist was completed by participants in each group. Data was further analyzed by performing independent sample t-test and logistic regression model in SPSS.v.16.0. Results: The study findings indicated that the methamphetamine dependent group applied less problem-solving response and had lower reliance on seeking social support and cognitive evaluation compared with the controls. In addition, the methamphetamine dependent group applied significantly more emotional and physical control oriented responses compared with the controls. Discussion: The study results yielded that coping responses of the methamphetamine dependent group were less problem-focused strategies which show an impaired aspect of cognitive functioning which is subject to clinical and treatment implications. Study in the context of identifying aspects that are fundamental to understanding the neural mechanisms underlying emotion-cognition interactions in the paradigm of coping responses is discussed.

Numerical Study of Frequency-dependent Seismoelectric Coupling in Partially-saturated Porous Media

Directory of Open Access Journals (Sweden)

Djuraev Ulugbek

2017-01-01

Full Text Available The seismoelectric phenomenon associated with propagation of seismic waves in fluid-saturated porous media has been studied for many decades. The method has a great potential to monitor subsurface fluid saturation changes associated with production of hydrocarbons. Frequency of the seismic source has a significant impact on measurement of the seismoelectric effects. In this paper, the effects of seismic wave frequency and water saturation on the seismoelectric response of a partially-saturated porous media is studied numerically. The conversion of seismic wave to electromagnetic wave was modelled by extending the theoretically developed seismoelectric coupling coefficient equation. We assumed constant values of pore radius and zeta-potential of 80 micrometers and 48 microvolts, respectively. Our calculations of the coupling coefficient were conducted at various water saturation values in the frequency range of 10 kHz to 150 kHz. The results show that the seismoelectric coupling is frequency-dependent and decreases exponentially when frequency increases. Similar trend is seen when water saturation is varied at different frequencies. However, when water saturation is less than about 0.6, the effect of frequency is significant. On the other hand, when the water saturation is greater than 0.6, the coupling coefficient shows monotonous trend when water saturation is increased at constant frequency.

Frequency dependent changes in NMDAR-dependent synaptic plasticity

Directory of Open Access Journals (Sweden)

Arvind eKumar

2011-09-01

Full Text Available The NMDAR-dependent synaptic plasticity is thought to mediate several forms of learning, and can be induced by spike trains containing a small number of spikes occurring with varying rates and timing, as well as with oscillations. We computed the influence of these variables on the plasticity induced at a single NMDAR containing synapse using a reduced model that was analytically tractable, and these findings were confirmed using detailed, multi-compartment model. In addition to explaining diverse experimental results about the rate and timing dependence of synaptic plasticity, the model made several novel and testable predictions. We found that there was a preferred frequency for inducing long-term potentiation (LTP such that higher frequency stimuli induced lesser LTP, decreasing as 1/f when the number of spikes in the stimulus was kept fixed. Among other things, the preferred frequency for inducing LTP varied as a function of the distance of the synapse from the soma. In fact, same stimulation frequencies could induce LTP or LTD depending on the dendritic location of the synapse. Next, we found that rhythmic stimuli induced greater plasticity then irregular stimuli. Furthermore, brief bursts of spikes significantly expanded the timing dependence of plasticity. Finally, we found that in the ~5-15Hz frequency range both rate- and timing-dependent plasticity mechanisms work synergistically to render the synaptic plasticity most sensitive to spike-timing. These findings provide computational evidence that oscillations can have a profound influence on the plasticity of an NMDAR-dependent synapse, and show a novel role for the dendritic morphology in this process.

Ranging Behaviour of Commercial Free-Range Laying Hens

Directory of Open Access Journals (Sweden)

Leonard Ikenna Chielo

2016-04-01

Full Text Available In this study, the range use and behaviour of laying hens in commercial free-range flocks was explored. Six flocks were each visited on four separate days and data collected from their outdoor area (divided into zones based on distance from shed and available resources. These were: apron (0–10 m from shed normally without cover or other enrichments; enriched belt (10–50 m from shed where resources such as manmade cover, saplings and dust baths were provided; and outer range (beyond 50 m from shed with no cover and mainly grass pasture. Data collection consisted of counting the number of hens in each zone and recording behaviour, feather condition and nearest neighbour distance (NND of 20 birds per zone on each visit day. In addition, we used techniques derived from ecological surveys to establish four transects perpendicular to the shed, running through the apron, enriched belt and outer range. Number of hens in each 10 m × 10 m quadrat was recorded four times per day as was the temperature and relative humidity of the outer range. On average, 12.5% of hens were found outside. Of these, 5.4% were found in the apron; 4.3% in the enriched zone; and 2.8% were in the outer range. This pattern was supported by data from quadrats, where the density of hens sharply dropped with increasing distance from shed. Consequently, NND was greatest in the outer range, least in the apron and intermediate in the enriched belt. Hens sampled in outer range and enriched belts had better feather condition than those from the apron. Standing, ground pecking, walking and foraging were the most commonly recorded activities with standing and pecking most likely to occur in the apron, and walking and foraging more common in the outer range. Use of the outer range declined with lower temperatures and increasing relative humidity, though use of apron and enriched belt was not affected by variation in these measures. These data support previous findings that outer range

SU-F-T-561: Energy Dependence of a Scintillation Detector

Energy Technology Data Exchange (ETDEWEB)

Volotskova, O; Xu, A; Jozsef, G [NYU Medical Center, New York, NY (United States)

2016-06-15

Purpose: To investigate the response and dose rate dependence of a scintillation detector over a wide energy range. Methods: The energy dependence of W1 scintillation detector was tested with: 1) 50–225 keV beams generated by an animal irradiator, 2) a Leksell Gamma Knife Perfexion Co-60 source, 3) 6MV, 6FFF, 10FFF and 15MV photon beams, and 4) 6–20MeV electron beams from a linac. Calibrated linac beams were used to deliver 100 cGy to the detector at dmax in water under reference conditions. The gamma-knife measurement was performed in solid water (100 cGy with 16mm collimator). The low energy beams were calibrated with an ion chamber in air (TG-61), and the scintillation detector was placed at the same location as the ionization chamber during calibration. For the linac photon and electron beams, dose rate dependence was tested for 100–2400 and 100–800 MU/min. Results: The scintillation detector demonstrated strong energy dependence in the range of 50–225keV. The measured values were lower than the delivered dose and increased as the energy increased. Therapeutic photon beams showed energy independence with variations less than 1%. Therapeutic electron beams displayed the same sensitivity of ∼2–3% at their corresponding dmax depths. The change in dose-rate of photon and electron beams within the therapeutic energy range did not affect detector output (<0.5%). Measurements acquired with the gamma knife showed that the output data agreed with the delivered dose up to 3%. Conclusion: W1 scintillation detector output has a strong energy dependence in the diagnostic and orthovoltage energy range. Therapeutic photon beams exhibited energy independence with no observable dose-rate dependence. This study may aid in the implementation of a scintillation detector in QA programs by providing energy calibration factors.

Helioseismology with long-range dark matter-baryon interactions

Energy Technology Data Exchange (ETDEWEB)

Lopes, Ilídio [Centro Multidisciplinar de Astrofísica, Instituto Superior Técnico, Universidade Tecnica de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Panci, Paolo [CP3-Origins and DIAS, University of Southern Denmark, DK-5230 Odense (Denmark); Silk, Joseph, E-mail: ilidio.lopes@tecnico.ulisboa.pt, E-mail: panci@iap.fr, E-mail: silk@astro.ox.ac.uk [Institut d' Astrophysique, UMR 7095 CNRS, Université Pierre et Marie Curie, 98bis Blvd Arago, F-75014 Paris (France)

2014-11-10

Assuming the existence of a primordial asymmetry in the dark sector, we study how long-range dark matter (DM)-baryon interactions, induced by the kinetic mixing of a new U(1) gauge boson and a photon, affect the evolution of the Sun and, in turn, the sound speed the profile obtained from helioseismology. Thanks to the explicit dependence on the exchanged momenta in the differential cross section (Rutherford-like scattering), we find that DM particles with a mass of ∼10 GeV, kinetic mixing parameter of the order of 10{sup –9}, and a mediator with a mass smaller than a few MeV improve the agreement between the best solar model and the helioseismic data without being excluded by direct detection experiments. In particular, the LUX detector will soon be able to either constrain or confirm our best-fit solar model in the presence of a dark sector with long-range interactions that reconcile helioseismology with thermal neutrino results.

Dose-dependent transitions in mechanisms of toxicity: case studies

International Nuclear Information System (INIS)

Slikker, William; Andersen, Melvin E.; Bogdanffy, Matthew S.; Bus, James S.; Cohen, Steven D.; Conolly, Rory B.; David, Raymond M.; Doerrer, Nancy G.; Dorman, David C.; Gaylor, David W.; Hattis, Dale; Rogers, John M.; Setzer, R. Woodrow; Swenberg, James A.; Wallace, Kendall

2004-01-01

Experience with dose response and mechanisms of toxicity has shown that multiple mechanisms may exist for a single agent along the continuum of the full dose-response curve. It is highly likely that critical, limiting steps in any given mechanistic pathway may become overwhelmed with increasing exposures, signaling the emergence of new modalities of toxic tissue injury at these higher doses. Therefore, dose-dependent transitions in principal mechanisms of toxicity may occur, and could have significant impact on the interpretation of reference data sets for risk assessment. To illustrate the existence of dose-dependent transitions in mechanisms of toxicity, a group of academic, government, and industry scientists, formed under the leadership of the ILSI Health and Environmental Sciences Institute (HESI), developed a series of case studies. These case studies included acetaminophen, butadiene, ethylene glycol, formaldehyde, manganese, methylene chloride, peroxisome proliferator-activated receptor (PPAR), progesterone/hydroxyflutamide, propylene oxide, vinyl acetate, vinyl chloride, vinylidene chloride, and zinc. The case studies formed the basis for technical discourse at two scientific workshops in 2003

Dependence of conductivity on thickness within the variable-range hopping regime for Coulomb glasses

Directory of Open Access Journals (Sweden)

M. Caravaca

Full Text Available In this paper, we provide some computational evidence concerning the dependence of conductivity on the system thickness for Coulomb glasses. We also verify the Efros–Shklovskii law and deal with the calculation of its characteristic parameter as a function of the thickness. Our results strengthen the link between theoretical and experimental fields. Keywords: Coulomb glass, Conductivity, Density of states, Efros–Shklovskii law

On the temperature dependence of flammability limits of gases.

Science.gov (United States)

Kondo, Shigeo; Takizawa, Kenji; Takahashi, Akifumi; Tokuhashi, Kazuaki

2011-03-15

Flammability limits of several combustible gases were measured at temperatures from 5 to 100 °C in a 12-l spherical flask basically following ASHRAE method. The measurements were done for methane, propane, isobutane, ethylene, propylene, dimethyl ether, methyl formate, 1,1-difluoroethane, ammonia, and carbon monoxide. As the temperature rises, the lower flammability limits are gradually shifted down and the upper limits are shifted up. Both the limits shift almost linearly to temperature within the range examined. The linear temperature dependence of the lower flammability limits is explained well using a limiting flame temperature concept at the lower concentration limit (LFL)--'White's rule'. The geometric mean of the flammability limits has been found to be relatively constant for many compounds over the temperature range studied (5-100 °C). Based on this fact, the temperature dependence of the upper flammability limit (UFL) can be predicted reasonably using the temperature coefficient calculated for the LFL. However, some compounds such as ethylene and dimethyl ether, in particular, have a more complex temperature dependence. Copyright © 2011 Elsevier B.V. All rights reserved.

Note: long-range scanning tunneling microscope for the study of nanostructures on insulating substrates.

Science.gov (United States)

Molina-Mendoza, Aday J; Rodrigo, José G; Island, Joshua; Burzuri, Enrique; Rubio-Bollinger, Gabino; van der Zant, Herre S J; Agraït, Nicolás

2014-02-01

The scanning tunneling microscope (STM) is a powerful tool for studying the electronic properties at the atomic level, however, it is of relatively small scanning range and the fact that it can only operate on conducting samples prevents its application to study heterogeneous samples consisting of conducting and insulating regions. Here we present a long-range scanning tunneling microscope capable of detecting conducting micro and nanostructures on insulating substrates using a technique based on the capacitance between the tip and the sample and performing STM studies.

Note: Long-range scanning tunneling microscope for the study of nanostructures on insulating substrates

Energy Technology Data Exchange (ETDEWEB)

Molina-Mendoza, Aday J., E-mail: aday.molina@uam.es [Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, Campus de Cantoblanco, E-28049 Madrid (Spain); Rodrigo, José G.; Rubio-Bollinger, Gabino [Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, Campus de Cantoblanco, E-28049 Madrid (Spain); Condensed Matter Physics Center (IFIMAC) and Instituto Universitario de Ciencia de Materiales “Nicolás Cabrera,” Universidad Autónoma de Madrid, Campus de Cantoblanco, E-28049 Madrid (Spain); Island, Joshua; Burzuri, Enrique; Zant, Herre S. J. van der [Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft (Netherlands); Agraït, Nicolás [Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, Campus de Cantoblanco, E-28049 Madrid (Spain); Condensed Matter Physics Center (IFIMAC) and Instituto Universitario de Ciencia de Materiales “Nicolás Cabrera,” Universidad Autónoma de Madrid, Campus de Cantoblanco, E-28049 Madrid (Spain); Instituto Madrileño de Estudios Avanzados en Nanociencia IMDEA-Nanociencia, E-28049 Madrid (Spain)

2014-02-15

The scanning tunneling microscope (STM) is a powerful tool for studying the electronic properties at the atomic level, however, it is of relatively small scanning range and the fact that it can only operate on conducting samples prevents its application to study heterogeneous samples consisting of conducting and insulating regions. Here we present a long-range scanning tunneling microscope capable of detecting conducting micro and nanostructures on insulating substrates using a technique based on the capacitance between the tip and the sample and performing STM studies.

Predictors of social anxiety in an opioid dependent sample and a control sample

OpenAIRE

Shand, Fiona L.; Degenhardt, Louisa; Nelson, Elliot C.; Mattick, Richard P.

2010-01-01

Compared to other mental health problems, social anxiety is under-acknowledged amongst opioid dependent populations. This study aimed to assess levels of social anxiety and identify its predictors in an opioid dependent sample and a matched control group. Opioid dependent participants (n = 1385) and controls (n = 417) completed the Social Interaction Anxiety Scale (SIAS), the Social Phobia Scale (SPS) and a diagnostic interview. Regression analyses were used to test a range of predictors of s...

Assessment of abstract reasoning abilities in alcohol-dependent subjects: an fMRI study

International Nuclear Information System (INIS)

Bagga, Deepika; Singh, Namita; Singh, Sadhana; Modi, Shilpi; Kumar, Pawan; Bhattacharya, D.; Garg, Mohan L.; Khushu, Subash

2014-01-01

Chronic alcohol abuse has been traditionally associated with impaired cognitive abilities. The deficits are most evident in higher order cognitive functions, such as abstract reasoning, problem solving and visuospatial processing. The present study sought to increase current understanding of the neuropsychological basis of poor abstract reasoning abilities in alcohol-dependent subjects using functional magnetic resonance imaging (fMRI). An abstract reasoning task-based fMRI study was carried out on alcohol-dependent subjects (n = 18) and healthy controls (n = 18) to examine neural activation pattern. The study was carried out using a 3-T whole-body magnetic resonance scanner. Preprocessing and post processing was performed using SPM 8 software. Behavioral data indicated that alcohol-dependent subjects took more time than controls for performing the task but there was no significant difference in their response accuracy. Analysis of the fMRI data indicated that for solving abstract reasoning-based problems, alcohol-dependent subjects showed enhanced right frontoparietal neural activation involving inferior frontal gyrus, post central gyrus, superior parietal lobule, and occipito-temporal gyrus. The extensive activation observed in alcohol dependents as compared to controls suggests that alcohol dependents recruit additional brain areas to meet the behavioral demands for equivalent task performance. The results are consistent with previous fMRI studies suggesting decreased neural efficiency of relevant brain networks or compensatory mechanisms for the execution of task for showing an equivalent performance. (orig.)

Assessment of abstract reasoning abilities in alcohol-dependent subjects: an fMRI study

Energy Technology Data Exchange (ETDEWEB)

Bagga, Deepika; Singh, Namita; Singh, Sadhana; Modi, Shilpi; Kumar, Pawan [Institute of Nuclear Medicine and Allied Sciences (INMAS), NMR Research Centre, Delhi (India); Bhattacharya, D. [Base Hospital, Department of Psychiatry, Delhi Cantt (India); Garg, Mohan L. [Panjab University, Department of Biophysics, Chandigarh (India); Khushu, Subash [Institute of Nuclear Medicine and Allied Sciences (INMAS), NMR Research Centre, Delhi (India); INMAS, DRDO, NMR Research Centre, Delhi (India)

2014-01-15

Chronic alcohol abuse has been traditionally associated with impaired cognitive abilities. The deficits are most evident in higher order cognitive functions, such as abstract reasoning, problem solving and visuospatial processing. The present study sought to increase current understanding of the neuropsychological basis of poor abstract reasoning abilities in alcohol-dependent subjects using functional magnetic resonance imaging (fMRI). An abstract reasoning task-based fMRI study was carried out on alcohol-dependent subjects (n = 18) and healthy controls (n = 18) to examine neural activation pattern. The study was carried out using a 3-T whole-body magnetic resonance scanner. Preprocessing and post processing was performed using SPM 8 software. Behavioral data indicated that alcohol-dependent subjects took more time than controls for performing the task but there was no significant difference in their response accuracy. Analysis of the fMRI data indicated that for solving abstract reasoning-based problems, alcohol-dependent subjects showed enhanced right frontoparietal neural activation involving inferior frontal gyrus, post central gyrus, superior parietal lobule, and occipito-temporal gyrus. The extensive activation observed in alcohol dependents as compared to controls suggests that alcohol dependents recruit additional brain areas to meet the behavioral demands for equivalent task performance. The results are consistent with previous fMRI studies suggesting decreased neural efficiency of relevant brain networks or compensatory mechanisms for the execution of task for showing an equivalent performance. (orig.)

Study on the KM capacitor base thermometers in the 42-273 K range

International Nuclear Information System (INIS)

Luzganov, V.S.; Mats'ko, A.A.

1988-01-01

Thermometric characteristics of the KM-5a-HZ0 monolithic capacitors in the 42-273 K temperature range are studied. Capacitors capacitance - temperature relation is considered in details. The data reproducibility after 5, 23, 34, 50, 51 and 57 days is studied, the accuracy of temperature measurements by the given thermometers is determined. Recommendations on selection of cpacitors, suitable for application as thermometer, are given. These capacitors permit temperature measurement in the 42-225 K range with the error of ± 0.5 K, and above 225 K the error is ± 1K. 8 refs.; 1 fig.; 1 tab

Study of nuclear level density parameter and its temperature dependence

International Nuclear Information System (INIS)

Nasrabadi, M. N.; Behkami, A. N.

2000-01-01

The nuclear level density ρ is the basic ingredient required for theoretical studies of nuclear reaction and structure. It describes the statistical nuclear properties and is expressed as a function of various constants of motion such as number of particles, excitation energy and angular momentum. In this work the energy and spin dependence of nuclear level density will be presented and discussed. In addition the level density parameter α will be extracted from this level density information, and its temperature and mass dependence will be obtained

Collisional energy dependence of molecular ionization by metastable rare gas atoms

International Nuclear Information System (INIS)

Martin, R.M.; Parr, T.P.

1979-01-01

The collisional energy dependence of several molecular total ionization cross sections by metastable rare gas atoms was studied over the thermal energy region using the crossed molecular beam time-of-flight method. Results are reported for the collision systems He, Ne, and Ar ionizing the geometric isomers cis- and trans-dichloroethylene and ortho- and para-dichlorobenzene. The He ionization cross sections oscillate about an energy dependence of E/sup -1/2/ over the energy range 0.004--1.0 eV, and the Ar*+para-dichlorobenzene cross section oscillates about an energy dependence of E/sup -2/5/ over the energy range 0.011--0.64 eV. The remaining systems are characterized by ''bent'' E/sup -m/ dependences with m values of 0.56--0.70 at low energies changing to 0.07--0.29 at higher energies. Comparison with the slopes of the He* systems and the Ar*+para-dichlorobenzene system shows that the ''bent'' and ''oscillating'' energy dependences are similar except for the form of the cross section functions at the lowest energies. No systematic differences are found between the cross section energy dependences for ionization of different geometric isomers or for ionization by the different metastable rare gas atoms

Temperature-dependent Hall effect studies of ZnO thin films grown by metalorganic chemical vapour deposition

International Nuclear Information System (INIS)

Roro, K T; Dangbegnon, J K; Sivaraya, S; Westraadt, J E; Neethling, J H; Leitch, A W R; Botha, J R; Kassier, G H

2008-01-01

The electrical properties of zinc oxide (ZnO) thin films of various thicknesses (0.3–4.4 µm) grown by metalorganic chemical vapour deposition on glass substrates have been studied by using temperature-dependent Hall-effect (TDH) measurements in the 18–300 K range. The high quality of the layers has been confirmed with x-ray diffraction, transmission electron microscopy, scanning electron microscopy and photoluminescence techniques. TDH measurements indicate the presence of a degenerate layer which significantly influences the low-temperature data. It is found that the measured mobility generally increases with increasing layer thickness, reaching a value of 120 cm 2 V −1 s −1 at room temperature for the 4.4 µm thick sample. The lateral grain size of the layers is also found to increase with thickness indicating a clear correlation between the size of the surface grains and the electrical properties of corresponding films. Theoretical fits to the Hall data suggest that the bulk conduction of the layers is dominated by a weakly compensated donor with activation energy in the 33–41 meV range and concentration of the order of 10 17 cm −3 , as well as a total acceptor concentration of mid-10 15 cm −3 . Grain boundary scattering is found to be an important limiting factor of the mobility throughout the temperature range considered

Scale dependence of deuteron electrodisintegration

Science.gov (United States)

More, S. N.; Bogner, S. K.; Furnstahl, R. J.

2017-11-01

Background: Isolating nuclear structure properties from knock-out reactions in a process-independent manner requires a controlled factorization, which is always to some degree scale and scheme dependent. Understanding this dependence is important for robust extractions from experiment, to correctly use the structure information in other processes, and to understand the impact of approximations for both. Purpose: We seek insight into scale dependence by exploring a model calculation of deuteron electrodisintegration, which provides a simple and clean theoretical laboratory. Methods: By considering various kinematic regions of the longitudinal structure function, we can examine how the components—the initial deuteron wave function, the current operator, and the final-state interactions (FSIs)—combine at different scales. We use the similarity renormalization group to evolve each component. Results: When evolved to different resolutions, the ingredients are all modified, but how they combine depends strongly on the kinematic region. In some regions, for example, the FSIs are largely unaffected by evolution, while elsewhere FSIs are greatly reduced. For certain kinematics, the impulse approximation at a high renormalization group resolution gives an intuitive picture in terms of a one-body current breaking up a short-range correlated neutron-proton pair, although FSIs distort this simple picture. With evolution to low resolution, however, the cross section is unchanged but a very different and arguably simpler intuitive picture emerges, with the evolved current efficiently represented at low momentum through derivative expansions or low-rank singular value decompositions. Conclusions: The underlying physics of deuteron electrodisintegration is scale dependent and not just kinematics dependent. As a result, intuition about physics such as the role of short-range correlations or D -state mixing in particular kinematic regimes can be strongly scale dependent

Temperature dependence of piezoelectric properties for textured SBN ceramics.

Science.gov (United States)

Kimura, Masahiko; Ogawa, Hirozumi; Kuroda, Daisuke; Sawada, Takuya; Higuchi, Yukio; Takagi, Hiroshi; Sakabe, Yukio

2007-12-01

Temperature dependences of piezoelectric properties were studied for h001i textured ceramics of bismuth layer-structured ferroelectrics, SrBi(2)Nb(2)O(9) (SBN). The textured ceramics with varied orientation degrees were fabricated by templated, grain-growth method, and the temperature dependences of resonance frequency were estimated. Excellent temperature stability of resonance frequency was obtained for the 76% textured ceramics. The resonance frequency of the 76% textured specimens varied almost linearly over a wide temperature range. Therefore, the variation was slight, even in a high temperature region above 150 degrees C. Temperature stability of a quartz crystal oscillator is generally higher than that of a ceramic resonator around room temperature. The variation of resonance frequency for the 76% textured SrBi(2)Nb(2)O(9) was larger than that of oscillation frequency for a typical quartz oscillator below 150 degrees C also in this study. However, the variation of the textured SrBi(2)Nb(2)O(9) was smaller than that of the quartz oscillator over a wide temperature range from -50 to 250 degrees C. Therefore, textured SrBi(2)Nb(2)O(9) ceramics is a major candidate material for the resonators used within a wide temperature range.

Non-destructive study of the ion-implantation-affected zone (the long-range effect) in titanium nitride

International Nuclear Information System (INIS)

Perry, A.J.; Treglio, J.R.; Schaffer, J.P.; Brunner, J.; Valvoda, V.; Rafaja, D.

1994-01-01

The depth to which metal ion implantation can change the structure of titanium nitride coatings is studied using two techniques - positron annihilation spectroscopy (PAS) and glancing-angle X-ray diffraction (GA-XRD) -which are normally applied to the study of bulk materials. The PAS results indicate that the depth to which vacancies are found greatly exceeds the depth at which the implanted material resides. In addition, the concentration of vacancies continues to increase with the dose of implanted ions. The GA-XRD data show that the implantation does not change the residual stress - it remains slightly tensile. Furthermore, there is an increase in the diffraction peak broadening, which is attributed to an increase in the local strain distribution resulting from the generation of a dislocation network at depths of up to several tenths of a micrometer below the implanted zone. The data support the view of a long-range effect, where metal ion implantation causes lattice defect generation within an implantation-affected zone (IAZ) to depths well beyond the implanted zone. The defective nature of the IAZ depends on the implanted dose and the acceleration voltage, as well as on the nature of the ions implanted. In the present work, there is no residual stress in the samples, so this cannot induce the IAZ. ((orig.))

Temperature dependence of low-frequency polarized Raman scattering spectra in TlInS{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Paucar, Raul; Wakita, Kazuki [Electronics and Computer Engineering, Chiba Institute of Technology, Chiba (Japan); Shim, YongGu; Mimura, Kojiro [Graduate School of Engineering, Osaka Prefecture University, Osaka (Japan); Alekperov, Oktay; Mamedov, Nazim [Institute of Physics, Azerbaijan National Academy of Sciences, Baku (Azerbaijan)

2017-06-15

In this work, we examined phase transitions in the layered ternary thallium chalcogenide TlInS{sub 2} by studying the temperature dependence of polarized Raman spectra with the aid of the Raman confocal microscope system. The Raman spectra were measured over the temperature range of 77-320 K (which includes the range of successive phase transitions) in the low-frequency region of 35-180 cm{sup -1}. The optical phonons that showed strong temperature dependence were identified as interlayer vibrations related to phase transitions, while the phonons that showed weak temperature dependence were identified as intralayer vibrations. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Feasibility of RACT for 3D dose measurement and range verification in a water phantom.

Science.gov (United States)

Alsanea, Fahed; Moskvin, Vadim; Stantz, Keith M

2015-02-01

The objective of this study is to establish the feasibility of using radiation-induced acoustics to measure the range and Bragg peak dose from a pulsed proton beam. Simulation studies implementing a prototype scanner design based on computed tomographic methods were performed to investigate the sensitivity to proton range and integral dose. Derived from thermodynamic wave equation, the pressure signals generated from the dose deposited from a pulsed proton beam with a 1 cm lateral beam width and a range of 16, 20, and 27 cm in water using Monte Carlo methods were simulated. The resulting dosimetric images were reconstructed implementing a 3D filtered backprojection algorithm and the pressure signals acquired from a 71-transducer array with a cylindrical geometry (30 × 40 cm) rotated over 2π about its central axis. Dependencies on the detector bandwidth and proton beam pulse width were performed, after which, different noise levels were added to the detector signals (using 1 μs pulse width and a 0.5 MHz cutoff frequency/hydrophone) to investigate the statistical and systematic errors in the proton range (at 20 cm) and Bragg peak dose (of 1 cGy). The reconstructed radioacoustic computed tomographic image intensity was shown to be linearly correlated to the dose within the Bragg peak. And, based on noise dependent studies, a detector sensitivity of 38 mPa was necessary to determine the proton range to within 1.0 mm (full-width at half-maximum) (systematic error ionizing radiation-induced acoustics can be used to verify dose distribution and proton range with centi-Gray sensitivity. Realizing this technology into the clinic has the potential to significantly impact beam commissioning, treatment verification during particle beam therapy and image guided techniques.

Range distributions in multiply implanted targets

International Nuclear Information System (INIS)

Kostic, S.; Jimenez-Rodriguez, J.J.; Karpuzov, D.S.; Armour, D.G.; Carter, G.; Salford Univ.

1984-01-01

Range distributions in inhomogeneous binary targets have been investigated both theoretically and experimentally. Silicon single crystal targets [(111) orientation] were implanted with 40 keV Pb + ions to fluences in the range from 5x10 14 to 7.5x10 16 cm -2 prior to bombardment with 80 keV Kr + ions to a fluence of 5x10 15 cm -2 . The samples were analysed using high resolution Rutherford backscattering before and after the krypton implantation in order to determine the dependence of the krypton distribution on the amount of lead previously implanted. The theoretical analysis was undertaken using the formalism developed in [1] and the computer simulation was based on the MARLOWE code. The agreement between the experimental, theoretical and computational krypton profiles is very good and the results indicate that accurate prediction of ranges profiles in inhomogeneous binary targets is possible using available theoretical and computational treatments. (orig.)

Regression analysis using dependent Polya trees.

Science.gov (United States)

Schörgendorfer, Angela; Branscum, Adam J

2013-11-30

Many commonly used models for linear regression analysis force overly simplistic shape and scale constraints on the residual structure of data. We propose a semiparametric Bayesian model for regression analysis that produces data-driven inference by using a new type of dependent Polya tree prior to model arbitrary residual distributions that are allowed to evolve across increasing levels of an ordinal covariate (e.g., time, in repeated measurement studies). By modeling residual distributions at consecutive covariate levels or time points using separate, but dependent Polya tree priors, distributional information is pooled while allowing for broad pliability to accommodate many types of changing residual distributions. We can use the proposed dependent residual structure in a wide range of regression settings, including fixed-effects and mixed-effects linear and nonlinear models for cross-sectional, prospective, and repeated measurement data. A simulation study illustrates the flexibility of our novel semiparametric regression model to accurately capture evolving residual distributions. In an application to immune development data on immunoglobulin G antibodies in children, our new model outperforms several contemporary semiparametric regression models based on a predictive model selection criterion. Copyright © 2013 John Wiley & Sons, Ltd.

Correlates of benzodiazepine dependence in the Netherlands Study of Depression and Anxiety

NARCIS (Netherlands)

Manthey, L.; Lohbeck, M.; Giltay, E.J.; van Veena, T.; Zitman, F.G.; Penninx, B.W.J.H.

2012-01-01

Aims: Benzodiazepines (BZDs) are effective in the short term against anxiety and insomnia. However, some BZD users develop BZD dependence after a relatively short period of time. Therefore, we aimed to identify the risk factors of BZD dependence. Design: An observational cohort study. Setting: The

Overpotential-induced lability of the electronic overlap factor in long-range electrochemical electron transfer: charge and distance dependence

DEFF Research Database (Denmark)

Kornyshev, A. A.; Kuznetsov, A. M.; Nielsen, Jens Ulrik

2000-01-01

Long-distance electrochemical electron transfer exhibits approximately exponential dependence on the electron transfer distance. On the basis of a jellium model of the metal surface we show that the slope of the logarithm of the current vs. the transfer distance also depends strongly...

Biotin-dependent functions in adiposity: a study of monozygotic twin pairs.

Science.gov (United States)

Järvinen, E; Ismail, K; Muniandy, M; Bogl, L H; Heinonen, S; Tummers, M; Miettinen, S; Kaprio, J; Rissanen, A; Ollikainen, M; Pietiläinen, K H

2016-05-01

Biotin acts as a coenzyme for carboxylases regulating lipid and amino-acid metabolism. We investigated alterations of the biotin-dependent functions in obesity and the downstream effects of biotin restriction in adipocytes in vitro. Twenty-four monozygotic twin pairs discordant for body mass index (BMI). Mean within-pair difference (heavy-lean co-twin, Δ) of BMI was 6.0 kg m(-2) (range 3.1-15.2 kg m(-)(2)). Adipose tissue (AT) DNA methylation, gene expression of AT and adipocytes, and leukocytes (real-time quantitative PCR), serum biotin, C-reactive protein (CRP) and triglycerides were measured in the twins. Human adipocytes were cultured in low and control biotin concentrations and analyzed for lipid droplet content, mitochondrial morphology and mitochondrial respiration. The gene expression levels of carboxylases, PCCB and MCCC1, were upregulated in the heavier co-twins' leukocytes. ΔPCCB (r=0.91, P=0.0046) and ΔMCCC1 (r=0.79, P=0.036) correlated with ΔCRP within-pairs. Serum biotin levels were lower in the heavier (274 ng l(-1)) than in the lean co-twins (390 ng l(-1), P=0.034). ΔBiotin correlated negatively with Δtriglycerides (r=-0.56, P=0.045) within-pairs. In AT, HLCS and ACACB were hypermethylated and biotin cycle genes HLCS and BTD were downregulated (PBiotin-dependent carboxylases were downregulated (ACACA, ACACB, PCCB, MCCC2 and PC; Pbiotin had decreased lipid accumulation, altered mitochondrial morphology and deficient mitochondrial respiration. Biotin-dependent functions are modified by adiposity independent of genetic effects, and correlate with inflammation and hypertriglyceridemia. Biotin restriction decreases lipid accumulation and respiration, and alters mitochondrial morphology in adipocytes.

The Dutch Cannabis Dependence (CanDep) study on the course of frequent cannabis use and dependence: objectives, methods and sample characteristics

NARCIS (Netherlands)

van der Pol, P.; Liebregts, N.; de Graaf, R.; Korf, D.J.; van den Brink, W.; van Laar, M.

2011-01-01

This paper presents an overview of the prospective cohort design of the Dutch Cannabis Dependence (CanDep) study, which investigates (i) the three-year natural course of frequent cannabis use (≥ three days per week in the past 12 months) and cannabis dependence; and (ii) the factors involved in the

Energy dependence of relative abundances and periods of separate groups of delayed neutrons at neutron induced fission of 239Pu in a range of neutrons energies 0.37 - 5 MeV

International Nuclear Information System (INIS)

Roschenko, V.A.; Piksaikin, V.M.; Kazakov, L.E.; Isaev, S.G.; Korolev, G.G.; Tarasko, M.Z.; Tertychnyi, R.G.

2001-01-01

The fundamental role of delayed neutrons in behavior, control and safety of reactors is well known today. Delayed neutron data are of great interest not only for reactor physics but also for nuclear fission physics and astrophysics. The purpose of the present work was the measurement of energy dependence of delayed neutrons (DN) group parameters at fission of nuclei 239 Pu in a range of energies of primary neutrons from 0.37 up to 5 MeV. The measurements were executed on installation designed on the basis of the electrostatic accelerator of KG - 2.5 SSC RF IPPE. The data are obtained in 6-group representation. It is shown, that there is a significant energy dependence of DN group parameters in a range of primary neutrons energies from thermal meanings up to 5 MeV, which is expressed in reduction of the average half-life of nuclei of the DN precursors on 10 %. The data, received in the present work, can be used at creation of a set of group constants for reactors with an intermediate spectrum of neutrons. (authors)

a Study of the Concentration Dependence of Macromolecular Diffusion Using Photon Correlation Spectroscopy.

Science.gov (United States)

Marlowe, Robert Lloyd

The dynamic light scattering technique of photon correlation spectroscopy has been used to investigate the dependence of the mutual diffusion coefficient of a macromolecular system upon concentration. The first part of the research was devoted to the design and construction of a single-clipping autocorrelator based on newly-developed integrated circuits. The resulting 128 channel instrument can perform real time autocorrelation for sample time intervals >(, )10 (mu)s, and batch processed autocorrelation for intervals down to 3 (mu)s. An improved design for a newer, all-digital autocorrelator is given. Homodyne light scattering experiments were then undertaken on monodisperse solutions of polystyrene spheres. The single-mode TEM(,oo) beam of an argon-ion laser ((lamda) = 5145 (ANGSTROM)) was used as the light source; all solutions were studied at room temperature. The scattering angle was varied from 30(DEGREES) to 110(DEGREES). Excellent agreement with the manufacturer's specification for the particle size was obtained from the photon correlation studies. Finally, aqueous solutions of the globular protein ovalbumin, ranging in concentration from 18.9 to 244.3 mg/ml, were illuminated under the same conditions of temperature and wavelength as before; the homodyne scattered light was detected at a fixed scattering angle of 30(DEGREES). The single-clipped photocount autocorrelation function was analyzed using the homodyne exponential integral method of Meneely et al. The resulting diffusion coefficients showed a general linear dependence upon concentration, as predicted by the generalized Stokes-Einstein equation. However, a clear peak in the data was evident at c (TURNEQ) 100 mg/ml, which could not be explained on the basis of a non -interacting particle theory. A semi-quantitative approach based on the Debye-Huckel theory of electrostatic interactions is suggested as the probable cause for the peak's rise, and an excluded volume effect for its decline.

Influence of temperature on the spectral characteristics of semiconductor lasers in the visible range

Science.gov (United States)

Adamov, A. A.; Baranov, M. S.; Khramov, V. N.

2018-04-01

The results of studies on the effect of temperature on the output spectral characteristics of continuous semiconductor lasers of the visible range are presented. The paper presents the results of studying the spectral-optical radiation parameters of semiconductor lasers, their coherence lengths, and the dependence of the position of the spectral peak of the wavelength on temperature. This is necessary for the selection of the most optimal laser in order to use it for medical ophthalmologic diagnosis. The experiment was carried out using semiconductor laser modules based on a laser diode. The spectra were recorded by using a two-channel automated spectral complex based on the MDR-23 monochromator. Spectral dependences on the temperature of semiconductor lasers are obtained, in the range from 300 to 370 K. The possibility of determining the internal damage to the stabilization of laser modules without opening the case is shown, but only with the use of their spectral characteristics. The obtained data allow taking into account temperature characteristics and further optimization of parameters of such lasers when used in medical practice, in particular, in ophthalmologic diagnostics.

Comparative cation dependency of sugar transport by crustacean hepatopancreas and intestine

Directory of Open Access Journals (Sweden)

Ada Duka

2014-06-01

Full Text Available Glucose is transported in crustacean hepatopancreas and intestine by Na+-dependent co-transport, while Na+-dependent D-fructose influx has only been described for the hepatopancreas. It is still unclear if the two sugars are independently transported by two distinct cation-dependent co-transporter carrier systems. In this study, lobster (Homarus americanus hepatopancreas brush border membrane vesicles (BBMV were used to characterize, in detail, the cation-dependency of both D-[3H]-glucose and D-[3H]-fructose influxes, while in vitro perfused intestines were employed to determine the nature of cation-dependent sugar transport across this organ. Over the sodium concentration range of 0–100 mM, both [3H]-glucose and [3H]-fructose influxes (0.1 mM; 1 min uptakes by hepatopancreatic BBMV were hyperbolic functions of [Na+]. [3H]-glucose and [3H]-fructose influxes by hepatopancreatic BBMV over a potassium concentration range of 15–100 mM were hyperbolic functions of [K+]. Both sugars displayed significant (p<0.01 Na+/K+-dependent and cation-independent uptake processes. Transepithelial 25 µM [3H]-glucose and [3H]-fructose fluxes across lobster intestine over luminal sodium and potassium concentration ranges of 0–50 mM and 5–100 mM, respectively, were hyperbolic functions of luminal [Na+] and [K+]. As with hepatopancreatic sugar transport, transepithelial intestinal sugar transport exhibited both significant (p<0.01 Na+/K+-dependent and cation-independent processes. Results suggest that both D-glucose and D-fructose are transported by a single SGLT-type carrier in each organ with sodium being the “preferred”, high affinity, cation for both sugars in the hepatopancreas, and potassium being the “preferred”, high affinity, cation for both sugars in the intestine.

Conduction disturbances after TAVR: Electrophysiological studies and pacemaker dependency.

Science.gov (United States)

Makki, Nader; Dollery, Jenn; Jones, Danielle; Crestanello, Juan; Lilly, Scott

Permanent pacemaker (PPM) placement occurs in 5-20% of patients after transcatheter aortic valve replacement (TAVR). Although predictors of pacemaker implantation have been established, features that predispose patients to pacemaker utilization on follow up have not been widely reported. We performed a retrospective review of patients undergoing commercial TAVR between 2011 and 2016. We collated patients that underwent in-hospital PPM implantation and had a follow up of at least 3months. Data abstraction was performed for electrophysiological studies (EPS), pacemaker indication, timing, and device interrogation for pacemaker dependency on follow up. A total of 24 patients received in-hospital PPM post-TAVR (14% of total cohort), and mean follow up was 22months. Indications for PPM included resting complete heart block (CHB; 15/24, 63%), left bundle branch block and abnormal electrophysiological study (EPS; 7/24, 29%), alternating bundle branch block (1/24, 4%) and tachy-brady syndrome (1/24, 4%). Pacemaker dependency (underlying ventricular asystole, complete heart block, or >50% pacing) occurred in 8/24 patients (33%) during follow-up, 7 of whom had resting CHB, and one with CHB invoked during EPS. Pacemaker dependency after TAVR is common among those that exhibited CHB, but not among those with a prolonged HV delay during EPS. Although preliminary, these observations are relevant to management of rhythm disturbances after TAVR, and may inform the practice of EPS-based PPM implantation. Copyright © 2017 Elsevier Inc. All rights reserved.

Long-range correlations from colour confinement

International Nuclear Information System (INIS)

Jurkiewicz, J.; Zenczykowski, P.

1979-01-01

A class of independent parton emission models is generalized by the introduction of the colour degrees of freedom. In the proposed models colour confinement extorts strong long-range forward-backward correlations, the rise of one-particle inclusive distribution and the KNO scaling. It leads to the analytically calculable definite asymptotic predictions for the D/ ratio which depends only on the choice of the colour group. Multiplicity distribution develops a remarkably long tail. (author)

Founder takes all: density-dependent processes structure biodiversity.

Science.gov (United States)

Waters, Jonathan M; Fraser, Ceridwen I; Hewitt, Godfrey M

2013-02-01

Density-dependent processes play a key role in the spatial structuring of biodiversity. Specifically, interrelated demographic processes, such as gene surfing, high-density blocking, and competitive exclusion, can generate striking geographic contrasts in the distributions of genes and species. Here, we propose that well-studied evolutionary and ecological biogeographic patterns of postglacial recolonization, progressive island colonization, microbial sectoring, and even the 'Out of Africa' pattern of human expansion, are fundamentally similar, underpinned by a 'founder takes all' density-dependent principle. Additionally, we hypothesize that older historic constraints of density-dependent processes are seen today in the dramatic biogeographic shifts that occur in response to human-mediated extinction events, whereby surviving lineages rapidly expand their ranges to replace extinct sister taxa. Copyright © 2012 Elsevier Ltd. All rights reserved.

Exercise Dependence

Directory of Open Access Journals (Sweden)

Erdal Vardar

2012-06-01

Full Text Available Exercise dependence define a condition in which a person performs excessive exercise resulting in deterioration of his or her physical and mental health wellness. Despite many clinical research studies on exercise dependence, exact diagnostic criteria has not been developed yet. Clinical evidences concerning etiology, epidemiology, underlying mechanisms and treatment of exercise dependence are still not sufficient. Moreover, evaluation of this clinical disorder within dependency perspective is a fairly new concept. Recent studies have shown that exercise dependence has similar features like chemical substance dependence with regards to withdrawal and tolerance symptoms. The aim of this review was to briefly evaluate diagnostic and clinical features of exercise dependence. [Archives Medical Review Journal 2012; 21(3.000: 163-173

Individual Ranging Behaviour Patterns in Commercial Free-Range Layers as Observed through RFID Tracking.

Science.gov (United States)

Larsen, Hannah; Cronin, Greg M; Gebhardt-Henrich, Sabine G; Smith, Carolynn L; Hemsworth, Paul H; Rault, Jean-Loup

2017-03-09

In this exploratory study, we tracked free-range laying hens on two commercial flocks with Radio Frequency Identification (RFID) technology with the aim to examine individual hen variation in range use. Three distinct outdoor zones were identified at increasing distances from the shed; the veranda [0-2.4 m], close range [2.4-11.4 m], and far range [>11.4 m]. Hens' movements between these areas were tracked using radio frequency identification technology. Most of the hens in both flocks (68.6% in Flock A, and 82.2% in Flock B) accessed the range every day during the study. Of the hens that accessed the range, most hens accessed all three zones (73.7% in Flock A, and 84.5% in Flock B). Hens spent half of their time outdoors in the veranda area. Within-individual consistency of range use (daily duration and frequency) varied considerably, and hens which were more consistent in their daily range use spent more time on the range overall ( p ranging behaviour may help elucidate the implications of ranging for laying hens.

Frequency and Magnetic Field Dependence of the Skin Depth in Co-rich Soft Magnetic Microwires

Directory of Open Access Journals (Sweden)

A. Zhukov

2016-11-01

Full Text Available We studied giant magnetoimpedance (GMI effect in magnetically soft amorphous Co-rich microwires in the extended frequency range. From obtained experimentally dependences of GMI ratio on magnetic field and different frequencies we estimated the penetration depth and its dependence on applied magnetic field and frequency

Mass dependence of short-range correlations in nuclei and the EMC effect

Directory of Open Access Journals (Sweden)

Cosyn Wim

2014-03-01

Full Text Available We sketch an approximate method to quantify the number of correlated pairs in any nucleus A. It is based on counting independent-particle model (IPM nucleon-nucleon pairs in a relative S-state with no radial excitation. We show that IPM pairs with those quantum numbers are most prone to short-range correlations and are at the origin of the high-momentum tail of the nuclear momentum distributions. Our method allows to compute the a2 ratios extracted from inclusive electron scattering. Furthermore, our results reproduce the observed linear correlation between the number of correlated pairs and the magnitude of the EMC effect. We show that the width of the pair center-ofmass distribution in exclusive two-nucleon knockout yields information on the quantum numbers of the pairs.

Long-range and head-on beam-beam compensation studies in RHIC with lessons for the LHC

International Nuclear Information System (INIS)

Fischer, W.; Luo, Y.; Abreu, N.; Calaga, R.; Montag, C.; Robert-Demolaize, G.; Dorda, U.; Koutchouk, J.-P.; Sterbini, G.; Zimmermann, F.; Kim, H.-J.; Sen, T.; Shiltsev, V.; Valishev, A.; Qiang, J.; Kabel, A.

2009-01-01

Long-range as well as head-on beam-beam effects are expected to limit the LHC performance with design parameters. They are also important consideration for the LHC upgrades. To mitigate long-range effects, current carrying wires parallel to the beam were proposed. Two such wires are installed in RHIC where they allow studying the effect of strong long-range beam-beam effects, as well as the compensation of a single long-range interaction. The tests provide benchmark data for simulations and analytical treatments. Electron lenses were proposed for both RHIC and the LHC to reduce the head-on beam-beam effect. We present the experimental long-range beam-beam program at RHIC and report on head-on compensations studies based on simulations

Comparison of statistical approaches dealing with time-dependent confounding in drug effectiveness studies.

Science.gov (United States)

Karim, Mohammad Ehsanul; Petkau, John; Gustafson, Paul; Platt, Robert W; Tremlett, Helen

2018-06-01

In longitudinal studies, if the time-dependent covariates are affected by the past treatment, time-dependent confounding may be present. For a time-to-event response, marginal structural Cox models are frequently used to deal with such confounding. To avoid some of the problems of fitting marginal structural Cox model, the sequential Cox approach has been suggested as an alternative. Although the estimation mechanisms are different, both approaches claim to estimate the causal effect of treatment by appropriately adjusting for time-dependent confounding. We carry out simulation studies to assess the suitability of the sequential Cox approach for analyzing time-to-event data in the presence of a time-dependent covariate that may or may not be a time-dependent confounder. Results from these simulations revealed that the sequential Cox approach is not as effective as marginal structural Cox model in addressing the time-dependent confounding. The sequential Cox approach was also found to be inadequate in the presence of a time-dependent covariate. We propose a modified version of the sequential Cox approach that correctly estimates the treatment effect in both of the above scenarios. All approaches are applied to investigate the impact of beta-interferon treatment in delaying disability progression in the British Columbia Multiple Sclerosis cohort (1995-2008).

A cross-sectional study on tobacco use and dependence among women: Does menthol matter?

Science.gov (United States)

Rosenbloom, Judith; Rees, Vaughan W; Reid, Kathleen; Wong, Jeannie; Kinnunen, Taru

2012-11-27

The question of whether mentholation of cigarettes enhances tobacco dependence has generated conflicting findings. Potential mediating factors in a putative relationship between menthol use and tobacco dependence may include race and gender. While an association between menthol use and dependence is mixed, research on the role of race solely among women smokers is scarce. This study examined whether women menthol smokers have higher tobacco use and dependence than non-menthol smokers. Further, the study investigated differences between White and African American smokers. A cross-sectional study was conducted among 928 women seeking tobacco dependence treatment in Boston, Massachusetts. Measures obtained included preferred brand and menthol content, dependence markers (cigarettes per day (CPD); time to first cigarette in the morning; number of and longest previous quit attempts) and smoking history (age of initiation; years smoking; menthol or non-menthol cigarette preference). Analysis of variance (ANOVA) was used to detect interactions between menthol preference by race for continuous variables, and Pearson's chi-squared test was used for analyses with dichotomous variables. A greater proportion of menthol smokers smoked their first cigarette within five minutes of waking (p preferences. However, African American smokers smoked fewer CPD (pbrand for longer (p= .04). Women menthol smokers showed signs of greater tobacco dependence than non-menthol smokers. African Americans smoked fewer CPD but nevertheless had evidence of greater dependence.

Time-reversed lasing in the terahertz range and its preliminary study in sensor applications

Energy Technology Data Exchange (ETDEWEB)

Shen, Yun, E-mail: shenyunoptics@gmail.com [Department of Physics, Nanchang University, Nanchang 330031 (China); Liu, Huaqing [Department of Physics, Nanchang University, Nanchang 330031 (China); Deng, Xiaohua [Institute of Space Science and Technology, Nanchang University, Nanchang 330031 (China); Wang, Guoping [Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan 430072 (China)

2017-02-05

Time-reversed lasing in a uniform slab and a grating structure are investigated in the terahertz range. The results show that both the uniform slab and grating can support terahertz time-reversed lasing. Nevertheless, due to the tunable effective refractive index, the grating structure can not only exhibit time-reversed lasing more effectively and flexibly than a uniform slab, but also can realize significant absorption in a broader operating frequency range. Furthermore, applications of terahertz time-reversed lasing for novel concentration/thickness sensors are preliminarily studied in a single-channel coherent perfect absorber system. - Highlights: • Time-reversed lasing are investigated in the terahertz range. • The grating structure exhibit time-reversed lasing more effectively and flexibly than a uniform slab. • THz time-reversed lasing for novel concentration/thickness sensors are studied.

Study on Size-Dependent Young’s Modulus of a Silicon Nano beam by Molecular Dynamics Simulation

International Nuclear Information System (INIS)

Yu, H.; Sun, C.; Zhang, W.W.; Lei, S.Y.; Huang, K.A.

2013-01-01

Young’s modulus of a silicon nano beam with a rectangular cross-section is studied by molecular dynamics method. Dynamic simulations are performed for doubly clamped silicon nano beams with lengths ranging from 4.888 to 12.491 nm and cross-sections ranging from 1.22 nm ×1.22 nm to 3.39 nm × 3.39 nm. The results show that Young’s moduli of such small silicon nano beams are much higher than the value of Young’s modulus for bulk silicon. Moreover, the resonant frequency and Young’s modulus of the Si nano beam are strongly dependent not only on the size of the nano beam but also on surface effects. Young’s modulus increases significantly with the decreasing of the thickness of the silicon nano beam. This result qualitatively agrees with one of the conclusions based on a semi continuum model, in which the surface relaxation and the surface tension were taken into consideration. The impacts of the surface reconstruction with (2 ×1) dimmers on the resonant frequency and Young’s modulus are studied in this paper too. It is shown that the surface reconstruction makes the silicon nano beam stiffer than the one without the surface reconstruction, resulting in a higher resonant frequency and a larger Young’s modulus

Examining the time dependence of DAMA's modulation amplitude

Science.gov (United States)

Kelso, Chris; Savage, Christopher; Sandick, Pearl; Freese, Katherine; Gondolo, Paolo

2018-03-01

If dark matter is composed of weakly interacting particles, Earth's orbital motion may induce a small annual variation in the rate at which these particles interact in a terrestrial detector. The DAMA collaboration has identified at a 9.3σ confidence level such an annual modulation in their event rate over two detector iterations, DAMA/NaI and DAMA/LIBRA, each with ˜ 7 years of observations. This data is well fit by a constant modulation amplitude for the two iterations of the experiment. We statistically examine the time dependence of the modulation amplitudes, which "by eye" appear to be decreasing with time in certain energy ranges. We perform a chi-squared goodness of fit test of the average modulation amplitudes measured by the two detector iterations which rejects the hypothesis of a consistent modulation amplitude at greater than 80, 96, and 99.6% for the 2-4, 2-5 and 2-6 keVee energy ranges, respectively. We also find that among the 14 annual cycles there are three ≳ 3σ departures from the average in our estimated data in the 5-6 keVee energy range. In addition, we examined several phenomenological models for the time dependence of the modulation amplitude. Using a maximum likelihood test, we find that descriptions of the modulation amplitude as decreasing with time are preferred over a constant modulation amplitude at anywhere between 1σ and 3σ , depending on the phenomenological model for the time dependence and the signal energy range considered. A time dependent modulation amplitude is not expected for a dark matter signal, at least for dark matter halo morphologies consistent with the DAMA signal. New data from DAMA/LIBRA-phase2 will certainly aid in determining whether any apparent time dependence is a real effect or a statistical fluctuation.

Cervical isometric strength and range of motion of elite rugby union players: a cohort study.

Science.gov (United States)

Hamilton, David F; Gatherer, Don

2014-01-01

Head and neck injury is relatively common in Rugby Union. Despite this, strength and range-of-motion characteristics of the cervical spine are poorly characterised. The aim of this study was to provide data on the strength and range-of-motion of the cervical spine of professional rugby players to guide clinical rehabilitation. A cohort study was performed evaluating 27 players from a single UK professional rugby club. Cervical isometric strength and range-of-motion were assessed in 3 planes of reference. Anthropometric data was collected and multivariate regression modelling performed with a view to predicting cervical isometric strength. Largest forces were generated in extension, with broadly equal isometric side flexion forces at around 90% of extension values. The forwards generated significantly more force than the backline in all parameters bar flexion. The forwards had substantially reduced cervical range-of-motion and larger body mass, with differences observed in height, weight, neck circumference and chest circumference (p isometric extension (adjusted R(2) = 30.34). Rehabilitative training programs aim to restore individuals to pre-injury status. This work provides reference ranges for the strength and range of motion of the cervical spine of current elite level rugby players.

Two Generations of Path Dependence in Economics?

DEFF Research Database (Denmark)

Madsen, Mogens Ove

2010-01-01

Even if there is no fully articulated and generally accepted theory of Path Dependence it has eagerly been taken up across a wide range of social sciences – primarily coming from economics. Path Dependence is most of all a metaphor that offers reason to believe, that some political, social...

Contribution to the study of the unresolved resonance range of the neutrons cross sections

International Nuclear Information System (INIS)

Noguere, Gilles

2014-01-01

This document presents the statistical description of neutron cross sections in the unresolved resonance range. The modeling of the total cross section and of the 'shape - elastic' cross section is based on the 'average R-Matrix' formalism. The partial cross sections describing the radiative capture, elastic scattering, inelastic scattering and fission process are calculated using the Hauser-Feshbach formalism with width fluctuation corrections. In the unresolved resonance range, these models depend on the average resonance parameters (neutron strength function Sc, mean level spacing D c , average partial reaction widths Γ c , channel radius a c , effective radius R' and distant level parameter R-bar c ∞ ). The codes (NJOY, CALENDF...) dedicated to the processing of nuclear data libraries (JEFF, ENDF/B, JENDL, CENDL, BROND... ) use the average parameters to take into account the self-shielding phenomenon for the simulation of the neutron transport in Monte-Carlo (MCNP, TRIPOLI... ) and deterministic (APOLLO, ERANOS...) codes. The evaluation work consists in establishing a consistent set of average parameters as a function of the total angular momentum J of the system and of the orbital moment of the incident neutron l. The work presented in this paper aims to describe the links between the S-Matrix and the 'average R-Matrix' formalism for the calculation of Sc, R-bar c ∞ , ac and R'. (author) [fr

Tunable optical coherence tomography in the infrared range using visible photons

Science.gov (United States)

Paterova, Anna V.; Yang, Hongzhi; An, Chengwu; Kalashnikov, Dmitry A.; Krivitsky, Leonid A.

2018-04-01

Optical coherence tomography (OCT) is an appealing technique for bio-imaging, medicine, and material analysis. For many applications, OCT in mid- and far-infrared (IR) leads to significantly more accurate results. Reported mid-IR OCT systems require light sources and photodetectors which operate in mid-IR range. These devices are expensive and need cryogenic cooling. Here, we report a proof-of-concept demonstration of a wavelength tunable IR OCT technique with detection of only visible range photons. Our method is based on the nonlinear interference of frequency correlated photon pairs. The nonlinear crystal, introduced in the Michelson-type interferometer, generates photon pairs with one photon in the visible and another in the IR range. The intensity of detected visible photons depends on the phase and loss of IR photons, which interact with the sample under study. This enables us to characterize sample properties and perform imaging in the IR range by detecting visible photons. The technique possesses broad wavelength tunability and yields a fair axial and lateral resolution, which can be tailored to the specific application. The work contributes to the development of versatile 3D imaging and material characterization systems working in a broad range of IR wavelengths, which do not require the use of IR-range light sources and photodetectors.

Knock-on type exchange and the density dependence of an effective interaction

International Nuclear Information System (INIS)

Jeukenne, J.P.; Mahaux, C.

1981-01-01

We investigate the origin of the density-dependence of the strength of an effective interaction previously derived from a Brueckner-Hartree-Fock calculation of the optical-model potential in nuclear matter. From the analysis of a model based on the Hartree-Fock approximation and on a Yukawa interaction with a Majorana exchange component, we study to what extent this dependence derives from the momentum-dependence of the exchange contribution of the knock-on type. The model is also used to discuss zero-range pseudopotential methods for including this knock-on contribution. (orig.)

Feasibility of RACT for 3D dose measurement and range verification in a water phantom

Energy Technology Data Exchange (ETDEWEB)

Alsanea, Fahed [School of Health Sciences, Purdue University, 550 Stadium Mall Drive, West Lafayette, Indiana 47907-2051 (United States); Moskvin, Vadim [Radiation Oncology, Indiana University School of Medicine, 535 Barnhill Drive, RT 041, Indianapolis, Indiana 46202-5289 (United States); Stantz, Keith M., E-mail: kstantz@purdue.edu [School of Health Sciences, Purdue University, 550 Stadium Mall Drive, West Lafayette, Indiana 47907-2051 and Radiology and Imaging Sciences, Indiana University School of Medicine, 950 West Walnut Street, Indianapolis, Indiana 46202-5289 (United States)

2015-02-15

Purpose: The objective of this study is to establish the feasibility of using radiation-induced acoustics to measure the range and Bragg peak dose from a pulsed proton beam. Simulation studies implementing a prototype scanner design based on computed tomographic methods were performed to investigate the sensitivity to proton range and integral dose. Methods: Derived from thermodynamic wave equation, the pressure signals generated from the dose deposited from a pulsed proton beam with a 1 cm lateral beam width and a range of 16, 20, and 27 cm in water using Monte Carlo methods were simulated. The resulting dosimetric images were reconstructed implementing a 3D filtered backprojection algorithm and the pressure signals acquired from a 71-transducer array with a cylindrical geometry (30 × 40 cm) rotated over 2π about its central axis. Dependencies on the detector bandwidth and proton beam pulse width were performed, after which, different noise levels were added to the detector signals (using 1 μs pulse width and a 0.5 MHz cutoff frequency/hydrophone) to investigate the statistical and systematic errors in the proton range (at 20 cm) and Bragg peak dose (of 1 cGy). Results: The reconstructed radioacoustic computed tomographic image intensity was shown to be linearly correlated to the dose within the Bragg peak. And, based on noise dependent studies, a detector sensitivity of 38 mPa was necessary to determine the proton range to within 1.0 mm (full-width at half-maximum) (systematic error < 150 μm) for a 1 cGy Bragg peak dose, where the integral dose within the Bragg peak was measured to within 2%. For existing hydrophone detector sensitivities, a Bragg peak dose of 1.6 cGy is possible. Conclusions: This study demonstrates that computed tomographic scanner based on ionizing radiation-induced acoustics can be used to verify dose distribution and proton range with centi-Gray sensitivity. Realizing this technology into the clinic has the potential to significantly

Lung and chest wall impedances in the dog in normal range of breathing: effects of pulmonary edema.

Science.gov (United States)

Barnas, G M; Stamenović, D; Lutchen, K R

1992-09-01

We evaluated the effect of pulmonary edema on the frequency (f) and tidal volume (VT) dependences of respiratory system mechanical properties in the normal ranges of breathing. We measured resistance and elastance of the lungs (RL and EL) and chest wall of four anesthetized-paralyzed dogs during sinusoidal volume oscillations at the trachea (50-300 ml, 0.2-2 Hz), delivered at a constant mean airway pressure. Measurements were made before and after severe pulmonary edema was produced by injection of 0.06 ml/kg oleic acid into the right atrium. Chest wall properties were not changed by the injection. Before oleic acid, EL increased slightly with increasing f in each dog but was independent of VT. RL decreased slightly and was independent of VT from 0.2 to 0.4 Hz, but above 0.4 Hz it tended to increase with increasing flow, presumably due to the airway contribution. After oleic acid injection, EL and RL increased greatly. Large negative dependences of EL on VT and of RL on f were also evident, so that EL and RL after oleic acid changed two- and fivefold, respectively, within the ranges of f and VT studied. We conclude that severe pulmonary edema changes lung properties so as to make behavior VT dependent (i.e., nonlinear) and very frequency dependent in the normal range of breathing.

Study of CT-based positron range correction in high resolution 3D PET imaging

Energy Technology Data Exchange (ETDEWEB)

Cal-Gonzalez, J., E-mail: jacobo@nuclear.fis.ucm.es [Grupo de Fisica Nuclear, Dpto. Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Herraiz, J.L. [Grupo de Fisica Nuclear, Dpto. Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Espana, S. [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Vicente, E. [Grupo de Fisica Nuclear, Dpto. Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Instituto de Estructura de la Materia, Consejo Superior de Investigaciones Cientificas (CSIC), Madrid (Spain); Herranz, E. [Grupo de Fisica Nuclear, Dpto. Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Desco, M. [Unidad de Medicina y Cirugia Experimental, Hospital General Universitario Gregorio Maranon, Madrid (Spain); Vaquero, J.J. [Dpto. de Bioingenieria e Ingenieria Espacial, Universidad Carlos III, Madrid (Spain); Udias, J.M. [Grupo de Fisica Nuclear, Dpto. Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain)

2011-08-21

Positron range limits the spatial resolution of PET images and has a different effect for different isotopes and positron propagation materials. Therefore it is important to consider it during image reconstruction, in order to obtain optimal image quality. Positron range distributions for most common isotopes used in PET in different materials were computed using the Monte Carlo simulations with PeneloPET. The range profiles were introduced into the 3D OSEM image reconstruction software FIRST and employed to blur the image either in the forward projection or in the forward and backward projection. The blurring introduced takes into account the different materials in which the positron propagates. Information on these materials may be obtained, for instance, from a segmentation of a CT image. The results of introducing positron blurring in both forward and backward projection operations was compared to using it only during forward projection. Further, the effect of different shapes of positron range profile in the quality of the reconstructed images with positron range correction was studied. For high positron energy isotopes, the reconstructed images show significant improvement in spatial resolution when positron range is taken into account during reconstruction, compared to reconstructions without positron range modeling.

Study of CT-based positron range correction in high resolution 3D PET imaging

International Nuclear Information System (INIS)

Cal-Gonzalez, J.; Herraiz, J.L.; Espana, S.; Vicente, E.; Herranz, E.; Desco, M.; Vaquero, J.J.; Udias, J.M.

2011-01-01

Positron range limits the spatial resolution of PET images and has a different effect for different isotopes and positron propagation materials. Therefore it is important to consider it during image reconstruction, in order to obtain optimal image quality. Positron range distributions for most common isotopes used in PET in different materials were computed using the Monte Carlo simulations with PeneloPET. The range profiles were introduced into the 3D OSEM image reconstruction software FIRST and employed to blur the image either in the forward projection or in the forward and backward projection. The blurring introduced takes into account the different materials in which the positron propagates. Information on these materials may be obtained, for instance, from a segmentation of a CT image. The results of introducing positron blurring in both forward and backward projection operations was compared to using it only during forward projection. Further, the effect of different shapes of positron range profile in the quality of the reconstructed images with positron range correction was studied. For high positron energy isotopes, the reconstructed images show significant improvement in spatial resolution when positron range is taken into account during reconstruction, compared to reconstructions without positron range modeling.

Density functional theory studies on the structures and electronic communication of meso-ferrocenylporphyrins: long range orbital coupling via porphyrin core.

Science.gov (United States)

Zhang, Lijuan; Qi, Dongdong; Zhang, Yuexing; Bian, Yongzhong; Jiang, Jianzhuang

2011-02-01

The molecular and electronic structures together with the electronic absorption spectra of a series of metal free meso-ferrocenylporphyrins, namely 5-ferrocenylporphyrin (1), 5,10-diferrocenylporphyrin (2), 5,15-diferrocenylporphyrin (3), 5,10,15-triferrocenylporphyrin (4), and 5,10,15,20-tetraferrocenylporphyrin (5) have been studied with the density functional theory (DFT) and time-dependent density functional theory (TD-DFT) methods. For the purpose of comparative studies, metal free porphyrin without any ferrocenyl group (0) and isolated ferrocene (6) were also calculated. The effects of the number and position of meso-attached ferrocenyl substituents on their molecular and electronic structures, atomic charges, molecular orbitals, and electronic absorption spectra of 1-5 were systematically investigated. The orbital coupling is investigated in detail, explaining well the long range coupling of ferrocenyl substituents connected via porphyrin core and the systematic change in the electronic absorption spectra of porphyrin compounds. Copyright © 2010 Elsevier Inc. All rights reserved.

Robustness and Vulnerability of Networks with Dynamical Dependency Groups.

Science.gov (United States)

Bai, Ya-Nan; Huang, Ning; Wang, Lei; Wu, Zhi-Xi

2016-11-28

The dependency property and self-recovery of failure nodes both have great effects on the robustness of networks during the cascading process. Existing investigations focused mainly on the failure mechanism of static dependency groups without considering the time-dependency of interdependent nodes and the recovery mechanism in reality. In this study, we present an evolving network model consisting of failure mechanisms and a recovery mechanism to explore network robustness, where the dependency relations among nodes vary over time. Based on generating function techniques, we provide an analytical framework for random networks with arbitrary degree distribution. In particular, we theoretically find that an abrupt percolation transition exists corresponding to the dynamical dependency groups for a wide range of topologies after initial random removal. Moreover, when the abrupt transition point is above the failure threshold of dependency groups, the evolving network with the larger dependency groups is more vulnerable; when below it, the larger dependency groups make the network more robust. Numerical simulations employing the Erdős-Rényi network and Barabási-Albert scale free network are performed to validate our theoretical results.

Laser parameters of a Fe : ZnSe crystal in the 85-255-K temperature range

NARCIS (Netherlands)

Voronov, AA; Kozlovskii, [No Value; Korostelin, YV; Podmar'kov, YP; Frolov, MP

The temperature dependence of the efficiency of a laser based on a Fe:ZnSe crystal grown from the vapour phase by the free-growth method is studied in the 85-255-K temperature range. As the temperature was increased, the slope efficiency of the laser with respect to absorbed energy decreased from

Species invasion shifts the importance of predator dependence.

Science.gov (United States)

Griffen, Blaine D; Delaney, David G

2007-12-01

The strength of interference between foraging individuals can influence per capita consumption rates, with important consequences for predator and prey populations and system stability. Here we demonstrate how the replacement of a previously established invader, the predatory crab Carcinus maenas, by the recently invading predatory crab Hemigrapsus sanguineus shifts predation from a species that experiences strong predator interference (strong predator dependence) to one that experiences weak predator interference (weak predator dependence). We demonstrate using field experiments that differences in the strength of predator dependence persist for these species both when they forage on a single focal prey species only (the mussel Mytilus edulis) and when they forage more broadly across the entire prey community. This shift in predator dependence with species replacement may be altering the biomass across trophic levels, consistent with theoretical predictions, as we show that H. sanguineus populations are much larger than C. maenas populations throughout their invaded ranges. Our study highlights that predator dependence may differ among predator species and demonstrates that different predatory impacts of two conspicuous invasive predators may be explained at least in part by different strengths of predator dependence.

Modelled temperature-dependent excitability behaviour of a generalised human peripheral sensory nerve fibre.

Science.gov (United States)

Smit, Jacoba E; Hanekom, Tania; Hanekom, Johan J

2009-08-01

The objective of this study was to determine if a recently developed human Ranvier node model, which is based on a modified version of the Hodgkin-Huxley model, could predict the excitability behaviour in human peripheral sensory nerve fibres with diameters ranging from 5.0 to 15.0 microm. The Ranvier node model was extended to include a persistent sodium current and was incorporated into a generalised single cable nerve fibre model. Parameter temperature dependence was included. All calculations were performed in Matlab. Sensory nerve fibre excitability behaviour characteristics predicted by the new nerve fibre model at different temperatures and fibre diameters compared well with measured data. Absolute refractory periods deviated from measured data, while relative refractory periods were similar to measured data. Conduction velocities showed both fibre diameter and temperature dependence and were underestimated in fibres thinner than 12.5 microm. Calculated strength-duration time constants ranged from 128.5 to 183.0 micros at 37 degrees C over the studied nerve fibre diameter range, with chronaxie times about 30% shorter than strength-duration time constants. Chronaxie times exhibited temperature dependence, with values overestimated by a factor 5 at temperatures lower than body temperature. Possible explanations include the deviated absolute refractory period trend and inclusion of a nodal strangulation relationship.

Magnetic short range order and the exchange coupling in magnets

International Nuclear Information System (INIS)

Antropov, V.P.

2006-01-01

We discuss our recent results of time-dependent density functional simulations of magnetic properties of Fe and Ni at finite temperatures. These results indicated that a strong magnetic short range order is responsible for the magnetic properties of elementary Ni and any itinerant magnet in general. We demonstrated that one can use the value of the magnetic short range order parameter to produce new quantitative classification of magnets. We also discuss the nature of the exchange coupling and its connection with the short range order. The spin-wave like propagating and diffusive excitations in paramagnetic localized systems with small short range order have been predicted while in the itinerant systems the short range order is more complicated. The possible smallness of the quantum factor in the itinerant magnets with short range order is discussed

Preparation and temperature dependence of electrostriction properties for PMN-based composite ceramics

International Nuclear Information System (INIS)

Zhao Jingbo; Qu Shaobo; Du Hongliang; Zheng Yanju; Xu Zhuo

2009-01-01

Both low- and high-temperature units were prepared by columbite precursor method, and Pb(Mg 1/3 Nb 2/3 )O 3 (PMN)-based ferroelectric composite ceramics were prepared by conventional method, baking-block method and coating method, respectively. The effects of preparation methods on dielectric and electrostriction properties as well as the temperature-dependence property of the obtained composite ceramics were studied. The results show that compared with the samples prepared by traditional blend sintering method, of the samples prepared by baking-block and coating methods have much better dielectric and electrostriction properties. For those prepared by baking-block method, the electrostriction temperature-dependence properties are good in the range of 20-60 deg. C. For those prepared by coating method, the dielectric temperature-dependence properties are also good in the broad range of -30 to 70 deg. C, and the electrostriction temperature properties are better than those prepared by blending-block. Compared with the traditional blending sintering method, the dielectric and electrostriction temperature-dependence properties are much better, which effectively solves the problem of temperature properties existing in present engineering applications.

Analysis of Critical Infrastructure Dependencies and Interdependencies

Energy Technology Data Exchange (ETDEWEB)

Petit, Frederic [Argonne National Lab. (ANL), Argonne, IL (United States); Verner, Duane [Argonne National Lab. (ANL), Argonne, IL (United States); Brannegan, David [Argonne National Lab. (ANL), Argonne, IL (United States); Buehring, William [Argonne National Lab. (ANL), Argonne, IL (United States); Dickinson, David [Argonne National Lab. (ANL), Argonne, IL (United States); Guziel, Karen [Argonne National Lab. (ANL), Argonne, IL (United States); Haffenden, Rebecca [Argonne National Lab. (ANL), Argonne, IL (United States); Phillips, Julia [Argonne National Lab. (ANL), Argonne, IL (United States); Peerenboom, James [Argonne National Lab. (ANL), Argonne, IL (United States)

2015-06-01

The report begins by defining dependencies and interdependencies and exploring basic concepts of dependencies in order to facilitate a common understanding and consistent analytical approaches. Key concepts covered include; Characteristics of dependencies: upstream dependencies, internal dependencies, and downstream dependencies; Classes of dependencies: physical, cyber, geographic, and logical; and Dimensions of dependencies: operating environment, coupling and response behavior, type of failure, infrastructure characteristics, and state of operations From there, the report proposes a multi-phase roadmap to support dependency and interdependency assessment activities nationwide, identifying a range of data inputs, analysis activities, and potential products for each phase, as well as key steps needed to progress from one phase to the next. The report concludes by outlining a comprehensive, iterative, and scalable framework for analyzing dependencies and interdependencies that stakeholders can integrate into existing risk and resilience assessment efforts.

Range of motion of diabetic frozen shoulder recovers to the contralateral level

Science.gov (United States)

Vastamäki, Heidi; Ristolainen, Leena

2016-01-01

Objective To determine whether frozen shoulder heals equally well in patients with and without diabetes and whether dependency on insulin affects the outcome. Methods We retrospectively examined 178 patients with idiopathic frozen shoulder; 27 patients had diabetes. We evaluated range of motion, pain, and functional results. The mean follow-up was 9.7 years (SD, 7.1 years). Results In the presence of frozen shoulder, range of motion did not differ between patients with and without diabetes. At follow-up, range of motion in all directions of both the affected and unaffected shoulders of patients with diabetes was inferior to that of patients without diabetes. Among patients with diabetes, range of motion of the once-frozen shoulder reached the level of the unaffected shoulder. Patients with and without diabetes experienced similar pain except during exertion. The Constant–Murley score was not significantly different between the two groups, and insulin dependency did not lead to worse outcomes. Conclusion Frozen shoulder heals well in patients with diabetes. PMID:27856934

Two separate dose-dependent effects of paroxetine

DEFF Research Database (Denmark)

Nielsen, Anette Green; Pedersen, Rasmus Steen; Nøhr-Jensen, Lene

2010-01-01

PURPOSE: To investigate paroxetine's putative dose-dependent impact on pupil reaction and inhibition of the O-demethylation of tramadol. METHODS: Twelve healthy CYP2D6 extensive metabolizers participated in this double-blinded randomized five-way placebo controlled cross-over study; they received...... concentrations of (+/-)-tramadol and (+/-)-O-desmethyltramadol (M1) were determined. RESULTS: With placebo, the median maximum pupil diameter was 6.43 mm (range 5.45-7.75 mm) before tramadol and 6.22 mm (4.35-7.65 mm) after 50 mg of tramadol (P = 0.4935). Paroxetine resulted in a statistically significant, dose......-dependent dilatation of the pupil with a geometric mean difference of 1.17 (95% CI 1.10-1.24) after ingestion of 50 mg paroxetine (P inhibition...

Local order dependent impurity levels in alloy semiconductors

International Nuclear Information System (INIS)

Silva, C.E.T.G. da; Ecole Normale Superieure, 75 - Paris

1981-01-01

We develop a one band/may sites model for an isoelectronic impurity in a semiconductor alloy. The cluster-Bethe-lattice approximation is used to study the dependence of the impurity energy level upon the short range order (SRO) of the alloy. The Kikuchi parametrization is used to describe the latter. We take into account diagonal disorder only, with possible off-diagonal relaxation around the impurity site. All the inequivalent clusters of the impurity site and its first nearest neighbours are considered, thus including the important short range alloy potential fluctuations. Results are presented for the local density of impurity states, for different degrees of SRO in the alloy. (Author) [pt

Timing of electromyographic activity and ranges of motion during simple motor tasks of upper extremities

Directory of Open Access Journals (Sweden)

Syczewska Małgorzata

2017-10-01

Full Text Available Study aim: Improvement of the upper extremities’ performance is one of the key aims in the rehabilitation process. In order to achieve high effectiveness of this process the amount of functional improvement achieved by a patient during the therapy needs to be assessed. The aim of this study was to obtain electromyographic (EMG activity profiles of the upper extremity muscles during execution of simple tasks in healthy subjects. Additionally the ranges of wrist, elbow and shoulder joints were measured and reported during performed trials. The second aim was to determine whether the movement execution and ranges of move­ments and muscular activity depend on age. Material and methods: Twenty-eight healthy adults, age range 21 to 65 years old, participated in the study. Surface electrodes were placed bilaterally on 7 upper extremity muscles. To obtain information about the beginning and end of the movement task and ranges of upper extremity joints, 13 markers were placed on the elbows and wrists of both upper extremities. The move­ments of the segments were calculated (distal vs proximal in five simple functional tasks (each task involved only one joint, performed while sitting. Kinematic data were collected by the VICON 460 system, and electromyographic data with the Mo­tion Lab EMG system. Results: Charts of timing of EMG activity of the upper extremity muscles together with ranges of upper extremity joint motion were obtained. Conclusion: The results show that the number of muscles activated and the time (or percentage of the task during which they are active depend on the type of the task and age. These data can be used as a reference in evaluation of functional deficits of patients.

Effects of study time and meaningfulness on environmental context-dependent recognition.

Science.gov (United States)

Isarida, Takeo; Isarida, Toshiko K; Sakai, Tetsuya

2012-11-01

In two experiments, we examined whether the size of place-context-dependent recognition decreased with study time and with the meaningfulness of the to-be-remembered materials. A group of 80 undergraduates intentionally studied a list of words in a short (1.5 s per item) or a long (4.0 s per item) study-time condition (Exp. 1). Another 40 undergraduates studied lists consisting of words and nonwords in the long-study-time condition (Exp. 2). After a short retention interval, recognition for the targets was tested in the same or in a different context. Context was manipulated by means of the combination of place, subsidiary task, and experimenter. Significant context-dependent recognition discrimination was found for words in the short-study-time condition (Exp. 1), but not in the long-study-time condition (Exps. 1 and 2). Significant effects were found as well for nonwords, even in the long-study-time condition (Exp. 2). These results are explained well by an outshining account: that is, by principles of outshining and encoding specificity.

Surface Plasmon Polariton Resonance of Gold, Silver, and Copper Studied in the Kretschmann Geometry: Dependence on Wavelength, Angle of Incidence, and Film Thickness

Science.gov (United States)

Takagi, Kentaro; Nair, Selvakumar V.; Watanabe, Ryosuke; Seto, Keisuke; Kobayashi, Takayoshi; Tokunaga, Eiji

2017-12-01

Surface plasmon polariton (SPP) resonance spectra for noble metals (Au, Ag, and Cu) were comprehensively studied in the Kretschmann attenuated total reflection (ATR) geometry, in the wavelength (λ) range from 300 to 1000 nm with the angle of incidence (θ) ranging from 45 to 60° and the film thickness (d) ranging from 41 to 76 nm. The experimental plasmon resonance spectra were reproduced by a calculation that included the broadening effects as follows: (1) the imaginary part of the bulk dielectric constant, (2) the thickness-dependent radiative coupling of the SPP at the metal-air interface to the prism, (3) the lack of conservation of the wavevector parallel to the interface kx(k||) caused by the surface roughness, (4) scanning λ at a fixed θ (changing both energy and kx at the same time) over the SPP dispersion relation. For Au and Ag, the experimental results were in good agreement with the calculated results using the bulk dielectric constants, showing no film thickness dependence of the plasmon resonance energy. A method to extract the true width of the plasmon resonance from raw ATR spectra is proposed and the results are rigorously compared with those expected from the bulk dielectric function given in the literature. For Au and Ag, the width increases with energy, in agreement with that expected from the relaxation of bulk free electrons including the electron-electron interaction, but there is clear evidence of extra broadening, which is more significant for thinner films, possibly due to relaxation pathways intrinsic to plasmons near the interface. For Cu, the visibility of the plasmon resonance critically depends on the evaporation conditions, and low pressures and fast deposition rates are required. Otherwise, scattering from the surface roughness causes considerable broadening of the plasmon resonance, resulting in an apparently fixed resonance energy without clear incident angle dependence. For Cu, the observed plasmon dispersion agrees well with

Search for a spin-dependent short-range force between nucleons with a 3He/129Xe clock-comparison experiment

International Nuclear Information System (INIS)

Tullney, Kathlynne

2014-01-01

The standard model (SM) of particle physics describes all known particles and their interactions. However, the SM leaves many issues unresolved. For example, it only includes three of the four fundamental forces and does not clarify the question why in the strong interaction CP symmetry is violated due to its non-trivial vacuum structure is predicted (Θ-term), but experimentally unverifiable. The latter one is known as the strong CP-problem of quantum chromodynamics (QCD) and is solved by the Peccei-Quinn-Weinberg-Wilczek theory. This theory predicts a new and almost massless boson which is known as the axion. The axion feebly interacts with matter and therefore it is a good candidate for cold dark matter, too. Axions are produced by the Primakoff-effect, i.e. by conversion of photons which are scattered in the electromagnetic field, e.g. of atoms. The inverse Primakoff-effect, which converts axions to photons again, can be used for direct detection of galactic, solar, or laboratory axions. Cosmological and astrophysical observations constrain the mass of the axion from a few μeV to some meV (''axion mass window''). If the axion exists, then it mediates a CP violating, spin-dependent, short-range interaction between a fermion and the spin of another fermion. By verification of this interaction, the axion can be detected indirectly. In the framework of the present thesis an experiment to search for this spindependent short-range interaction was performed in the magnetically shielded room BMSR-2 of the Physikalisch-Technische Bundesanstalt Berlin. An ultra-sensitive low-field co-magnetometer was employed which is based on the detection of free precession of 3 He and 129 Xe nuclear spins using SQUIDs as low-noise magnetic flux detectors. The two nuclear spin polarized gases are filled into a glass cell which is immersed in a low magnetic field of about B 0 = 0.35 μT with absolute field gradients in the order of pT/cm. The spin precession frequencies of 3 He and 129

Long-range order in canary song.

Science.gov (United States)

Markowitz, Jeffrey E; Ivie, Elizabeth; Kligler, Laura; Gardner, Timothy J

2013-01-01

Bird songs range in form from the simple notes of a Chipping Sparrow to the rich performance of the nightingale. Non-adjacent correlations can be found in the syntax of some birdsongs, indicating that the choice of what to sing next is determined not only by the current syllable, but also by previous syllables sung. Here we examine the song of the domesticated canary, a complex singer whose song consists of syllables, grouped into phrases that are arranged in flexible sequences. Phrases are defined by a fundamental time-scale that is independent of the underlying syllable duration. We show that the ordering of phrases is governed by long-range rules: the choice of what phrase to sing next in a given context depends on the history of the song, and for some syllables, highly specific rules produce correlations in song over timescales of up to ten seconds. The neural basis of these long-range correlations may provide insight into how complex behaviors are assembled from more elementary, stereotyped modules.

Thickness dependent structural ordering, degradation and metastability in polysilane thin films: A photoluminescence study on representative σ-conjugated polymers

International Nuclear Information System (INIS)

Urbánek, Pavel; Kuřitka, Ivo

2015-01-01

We present a fundamental experimental study based on the fluorescence investigation of thin σ-conjugated polymer films, where the dependence of optoelectrical properties and UV degradation on film thickness ranging from nano- to microscale was studied. Such extensive and detailed study was performed for the first time and observed spectral shifts in emission and excitation spectra and UV degradation retardation point towards the conclusions that there exists a threshold thickness where the material degradation behavior, electron delocalization and structure suddenly change. The development of well aligned polymeric chain structure between the nano- and micrometer thickness (on the mesoscale) was shown responsible for the manifested phenomena. The material thicker than critical 500 nm has extremely small Stokes' shift, maximum extended σ-delocalization along the silicon polymer backbone and exhibits remarkable UV degradation slowdown and self-recovery ability. On the contrary, the electronic properties of thin films below 80 nm resemble those of random coils in solutions. The films of moderate thickness show relatively steep transition between these two modes of structural ordering and resulting properties. Altogether, we consider this complex phenomenon as a consequence of the mesoscale effect, which is an only recently introduced concept in polymer thin films. - Highlights: • Photoluminescence was used as a tool for structural investigation of polysilanes. • Primary study of strong dependence of thin polymer film structure on mesoscale. • A mesoscale effect observed for the first time on sigma conjugated polymers. • Conjugation length is dramatically extended in thicker films than in nanoscale. • Self-recovery effect was shown to be dependent on the mesoscale as well.

Study of uranium mineralization in rock samples from marwat range bannu basin by fission track analysis technique

International Nuclear Information System (INIS)

Qureshi, A.Z.; Ullah, K.; Ullah, N.; Akram, M.

2004-07-01

The Geophysics Division, Atomic Energy Minerals Centre (AEMC), Lahore has planned a uranium exploration program in Marwat Range, Bannu Basin. In this connection 30 thin sections of rock samples, collected from four areas; namely, Darra Tang, Simukili, Karkanwal and Sheikhillah from Marwat Range, and one from Salt Range were provided to Nuclear Geology Group of Physics Research Division, PINSTECH for the study of nature and mechanism of uranium mineralization These studies are aimed to help in designing uranium exploration strategy by providing the loci of uranium sources in the Marwat and Salt Ranges. The samples have been studied using fission track analysis technique. (author)

Efros-Shklovskii variable range hopping and nonlinear transport in 1 T /1 T'-MoS2

Science.gov (United States)

Papadopoulos, N.; Steele, G. A.; van der Zant, H. S. J.

2017-12-01

We have studied temperature- and electric-field-dependent carrier transport in single flakes of MoS2 treated with n -butyllithium. The temperature dependence of the four-terminal resistance follows the Efros-Shklovskii variable range hopping conduction mechanism. From measurements in the Ohmic and non-Ohmic regime, we estimate the localization length and the average hopping length of the carriers, as well as the effective dielectric constant. Furthermore, a comparison between two- and four-probe measurements yields a contact resistance that increases significantly with decreasing temperature.

Optical properties of InGaN thin films in the entire composition range

Science.gov (United States)

Kazazis, S. A.; Papadomanolaki, E.; Androulidaki, M.; Kayambaki, M.; Iliopoulos, E.

2018-03-01

The optical properties of thick InGaN epilayers, with compositions spanning the entire ternary range, are studied in detail. High structural quality, single phase InxGa1-xN (0001) films were grown heteroepitaxially by radio-frequency plasma assisted molecular-beam epitaxy on freestanding GaN substrates. Their emission characteristics were investigated by low temperature photoluminescence spectroscopy, whereas variable angle spectroscopic ellipsometry was applied to determine the complex dielectric function of the films, in the 0.55-4.0 eV photon range. Photoluminescence lines were intense and narrow, in the range of 100 meV for Ga-rich InGaN films (x 0.6). The composition dependence of the strain-free emission energy was expressed by a bowing parameter of b = 2.70 ± 0.12 eV. The films' optical dielectric function dispersion was obtained by the analysis of the ellipsometric data employing a Kramers-Kronig consistent parameterized optical model. The refractive index dispersion was obtained for alloys in the entire composition range, and the corresponding values at the band edge show a parabolic dependence on the InN mole fraction expressed by a bowing parameter of b = 0.81 ± 0.04. The bowing parameter describing the fundamental energy bandgap was deduced to be equal to 1.66 ± 0.07 eV, consistent with the ab initio calculations for statistically random (non-clustered) InGaN alloys.

Predicting the transition from frequent cannabis use to cannabis dependence: a three-year prospective study.

NARCIS (Netherlands)

van der Pol, P.; Liebregts, N.; de Graaf, R.; Korf, D.J.; van den Brink, W.; van Laar, M.

2013-01-01

Background Frequent cannabis users are at high risk of dependence, still most (near) daily users are not dependent. It is unknown why some frequent users develop dependence, whereas others do not. This study aims to identify predictors of first-incidence DSM-IV cannabis dependence in frequent

Improvement of range spatial resolution of medical ultrasound imaging by element-domain signal processing

Science.gov (United States)

Hasegawa, Hideyuki

2017-07-01

The range spatial resolution is an important factor determining the image quality in ultrasonic imaging. The range spatial resolution in ultrasonic imaging depends on the ultrasonic pulse length, which is determined by the mechanical response of the piezoelectric element in an ultrasonic probe. To improve the range spatial resolution without replacing the transducer element, in the present study, methods based on maximum likelihood (ML) estimation and multiple signal classification (MUSIC) were proposed. The proposed methods were applied to echo signals received by individual transducer elements in an ultrasonic probe. The basic experimental results showed that the axial half maximum of the echo from a string phantom was improved from 0.21 mm (conventional method) to 0.086 mm (ML) and 0.094 mm (MUSIC).

Cigarette smoking, nicotine dependence and anxiety disorders: a systematic review of population-based, epidemiological studies

Directory of Open Access Journals (Sweden)

Moylan Steven

2012-10-01

Full Text Available Abstract Background Multiple studies have demonstrated that rates of smoking and nicotine dependence are increased in individuals with anxiety disorders. However, significant variability exists in the epidemiological literature exploring this relationship, including study design (cross-sectional versus prospective, the population assessed (random sample versus clinical population and diagnostic instrument utilized. Methods We undertook a systematic review of population-based observational studies that utilized recognized structured clinical diagnostic criteria (Diagnostic and Statistical Manual of Mental Disorders (DSM or International Classification of Diseases (ICD for anxiety disorder diagnosis to investigate the relationship between cigarette smoking, nicotine dependence and anxiety disorders. Results In total, 47 studies met the predefined inclusion criteria, with 12 studies providing prospective information and 5 studies providing quasiprospective information. The available evidence suggests that some baseline anxiety disorders are a risk factor for initiation of smoking and nicotine dependence, although the evidence is heterogeneous and many studies did not control for the effect of comorbid substance use disorders. The identified evidence however appeared to more consistently support cigarette smoking and nicotine dependence as being a risk factor for development of some anxiety disorders (for example, panic disorder, generalized anxiety disorder, although these findings were not replicated in all studies. A number of inconsistencies in the literature were identified. Conclusions Although many studies have demonstrated increased rates of smoking and nicotine dependence in individuals with anxiety disorders, there is a limited and heterogeneous literature that has prospectively examined this relationship in population studies using validated diagnostic criteria. The most consistent evidence supports smoking and nicotine dependence as

Predicting the transition from frequent cannabis use to cannabis dependence: a three-year prospective study

NARCIS (Netherlands)

van der Pol, Peggy; Liebregts, Nienke; de Graaf, Ron; Korf, Dirk J.; van den Brink, Wim; van Laar, Margriet

2013-01-01

Frequent cannabis users are at high risk of dependence, still most (near) daily users are not dependent. It is unknown why some frequent users develop dependence, whereas others do not. This study aims to identify predictors of first-incidence DSM-IV cannabis dependence in frequent cannabis users. A

Change in Care Dependency of Stroke Patients: A Longitudinal and Multicenter Study

Directory of Open Access Journals (Sweden)

Nursiswati Nursiswati, MN

2017-06-01

Conclusions: Based on the findings of this study, we recommend that hospital-based and community-based services should include continual care dependence monitoring using this comprehensive instrument. Care dependency is subject to change over time, therefore nurses have to plan and tailor adequate nursing care measures to patient needs in the different stages, especially with respect to the aspect of mobility.

Temperature dependent tunneling study of CaFe{sub 1.96}Ni{sub 0.04}As{sub 2} single crystals

Energy Technology Data Exchange (ETDEWEB)

Dutta, Anirban, E-mail: adatta@iitk.ac.in; Gupta, Anjan K. [Department of Physics, IIT Kanpur, Kanpur-208 016 (India); Thamizhavel, A. [Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai-400 005 (India)

2014-04-24

We report on temperature dependent scanning tunneling microscopy and spectroscopy studies on CaFe{sub 1.96}Ni{sub 0.04}As{sub 2} single crystals in 5.4 – 19.7 K temperature range across the normal metal - superconductor transition temperature, T{sub C} = 14K. The in-situ cleaved crystals show reasonably flat surface with signatures of atomic resolution. The tunnel spectra show significant spatial inhomogeneity below T{sub C}, which reduces significantly as the temperature goes above the T{sub C}. We discuss these results in terms of an inhomogeneous electronic phase that may exist due to the vicinity of this composition to the quantum critical point.

Waterpipe dependence in university students and effect of normative beliefs: a cross-sectional study.

Science.gov (United States)

Salameh, P; Salamé, J; Waked, M; Barbour, B; Zeidan, N; Baldi, I

2014-02-14

The objective of this study was to measure the correlates, including normative beliefs, associated with waterpipe (WP) and cigarette smoking prevalence and dependence. A cross-sectional study was carried out using a proportionate cluster sample of Lebanese students in 17 public and private universities. Of the 4900 distributed questionnaires, 3384 (69.1%) were returned to the field worker. All available students during break times were approached, with no exclusion criteria. sociodemographic variables, detailed active and passive smoking, in addition to items of the tobacco dependence scales were all evaluated. Correlates to WP smoking were studying in a private university (adjusted OR, aOR=1.50 (1.26 to 1.79); pinfluence were found on smoking behaviour and dependence. Although the role of parents was not visible in decreasing the risk of smoking WP, their protective influence seemed more important on WP dependence (β=-1.09(-1.79 to -0.28); p1; pinfluenced by parents' and friends' opinions, and idols' smoking status. Future research is necessary to further improve our understanding of motives for WP smoking and dependence.

COREL, Ion Implantation in Solids, Range, Straggling Using Thomas-Fermi Cross-Sections. RASE4, Ion Implantation in Solids, Range, Straggling, Energy Deposition, Recoils. DAMG2, Ion Implantation in Solids, Energy Deposition Distribution with Recoils

International Nuclear Information System (INIS)

Brice, D. K.

1979-01-01

1 - Description of problem or function: COREL calculates the final average projected range, standard deviation in projected range, standard deviation in locations transverse to projected range, and average range along path for energetic atomic projectiles incident on amorphous targets or crystalline targets oriented such that the projectiles are not incident along low index crystallographic axes or planes. RASE4 calculates the instantaneous average projected range, standard deviation in projected range, standard deviation in locations transverse to projected range, and average range along path for energetic atomic projectiles incident on amorphous targets or crystalline targets oriented such that the projectiles are not incident along low index crystallographic axes or planes. RASE4 also calculates the instantaneous rate at which the projectile is depositing energy into atomic processes (damage) and into electronic processes (electronic excitation), the average range of target atom recoils projected onto the direction of motion of the projectiles, and the standard deviation in the recoil projected range. DAMG2 calculates the distribution in depth of the energy deposited into atomic processes (damage), electronic processes (electronic excitation), or other energy-dependent quality produced by energetic atomic projectiles incident on amorphous targets or crystalline targets oriented such that the projectiles are not incident along low index crystallographic axes or planes. 2 - Method of solution: COREL: The truncated differential equation which governs the several variables being sought is solved through second-order by trapezoidal integration. The energy-dependent coefficients in the equation are obtained by rectangular integration over the Thomas-Fermi elastic scattering cross section. RASE4: The truncated differential equation which governs the range and straggling variables is solved through second-order by trapezoidal integration. The energy-dependent

Energy dependence corrections to MOSFET dosimetric sensitivity

International Nuclear Information System (INIS)

Cheung, T.; Yu, P.K.N.; Butson, M.J.; Illawarra Cancer Care Centre, Crown St, Wollongong

2009-01-01

Metal Oxide Semiconductor Field Effect Transistors (MOSFET's) are dosimeters which are now frequently utilized in radiotherapy treatment applications. An improved MOSFET, clinical semiconductor dosimetry system (CSDS) which utilizes improved packaging for the MOSFET device has been studied for energy dependence of sensitivity to x-ray radiation measurement. Energy dependence from 50 kVp to 10 MV x-rays has been studied and found to vary by up to a factor of 3.2 with 75 kVp producing the highest sensitivity response. The detectors average life span in high sensitivity mode is energy related and ranges from approximately 100 Gy for 75 kVp x-rays to approximately 300 Gy at 6MV x-ray energy. The MOSFET detector has also been studied for sensitivity variations with integrated dose history. It was found to become less sensitive to radiation with age and the magnitude of this effect is dependant on radiation energy with lower energies producing a larger sensitivity reduction with integrated dose. The reduction in sensitivity is however approximated reproducibly by a slightly non linear, second order polynomial function allowing corrections to be made to reading to account for this effect to provide more accurate dose assessments both in phantom and in-vivo.

Energy dependence corrections to MOSFET dosimetric sensitivity.

Science.gov (United States)

Cheung, T; Butson, M J; Yu, P K N

2009-03-01

Metal Oxide Semiconductor Field Effect Transistors (MOSFET's) are dosimeters which are now frequently utilized in radiotherapy treatment applications. An improved MOSFET, clinical semiconductor dosimetry system (CSDS) which utilizes improved packaging for the MOSFET device has been studied for energy dependence of sensitivity to x-ray radiation measurement. Energy dependence from 50 kVp to 10 MV x-rays has been studied and found to vary by up to a factor of 3.2 with 75 kVp producing the highest sensitivity response. The detectors average life span in high sensitivity mode is energy related and ranges from approximately 100 Gy for 75 kVp x-rays to approximately 300 Gy at 6 MV x-ray energy. The MOSFET detector has also been studied for sensitivity variations with integrated dose history. It was found to become less sensitive to radiation with age and the magnitude of this effect is dependant on radiation energy with lower energies producing a larger sensitivity reduction with integrated dose. The reduction in sensitivity is however approximated reproducibly by a slightly non linear, second order polynomial function allowing corrections to be made to readings to account for this effect to provide more accurate dose assessments both in phantom and in-vivo.

Implications of climate change for wetland-dependent birds in the Prairie Pothole Region

Science.gov (United States)

Steen, Valerie; Skagen, Susan K.; Melcher, Cynthia P.

2016-01-01

The habitats and food resources required to support breeding and migrant birds dependent on North American prairie wetlands are threatened by impending climate change. The North American Prairie Pothole Region (PPR) hosts nearly 120 species of wetland-dependent birds representing 21 families. Strategic management requires knowledge of avian habitat requirements and assessment of species most vulnerable to future threats. We applied bioclimatic species distribution models (SDMs) to project range changes of 29 wetland-dependent bird species using ensemble modeling techniques, a large number of General Circulation Models (GCMs), and hydrological climate covariates. For the U.S. PPR, mean projected range change, expressed as a proportion of currently occupied range, was −0.31 (± 0.22 SD; range − 0.75 to 0.16), and all but two species were projected to lose habitat. Species associated with deeper water were expected to experience smaller negative impacts of climate change. The magnitude of climate change impacts was somewhat lower in this study than earlier efforts most likely due to use of different focal species, varying methodologies, different modeling decisions, or alternative GCMs. Quantification of the projected species-specific impacts of climate change using species distribution modeling offers valuable information for vulnerability assessments within the conservation planning process.

Influence of depression and early adverse experiences on illicit drug dependence: a case-control study.

Science.gov (United States)

Ferigolo, Maristela; Stein, Airton T; Fuchs, Flavio D; Barros, Helena M T

2009-06-01

The purpose of this study was to investigate the association between depression and illicit drug dependence among a Latin-American population. illicit drug dependent patients (n = 137) and controls (n = 274) were interviewed using the Diagnostic Interview for Genetic Studies, in order to detect lifetime and current depressive disorder and illicit (cocaine, cannabis or inhalants) substance dependence. A regression analysis was used to estimate the odds ratio for drug dependence according to the diagnosis of depression. The lifetime diagnosis of depression (p = 0.001; OR = 4.9; 95% CI, 1.9-12.7) predicts illegal drugs dependence. Sociodemographic variables such as male gender (p drug dependence. Additional influent factors detected were having parents (p = 0.006; OR = 18.9; 95% CI, 2.3-158) or friends (p illicit drugs dependents. although a causal relationship between dependence on illicit drugs and depression cannot be determined, comparison of the sequence of events point to the occurrence of depression later in life than dependence. It remains to be determined whether depression is a comorbidity of dependence, sharing etiological factors, or a consequence of drug abuse and/or abstinence.

An end-to-end assessment of range uncertainty in proton therapy using animal tissues

Science.gov (United States)

Zheng, Yuanshui; Kang, Yixiu; Zeidan, Omar; Schreuder, Niek

2016-11-01

Accurate assessment of range uncertainty is critical in proton therapy. However, there is a lack of data and consensus on how to evaluate the appropriate amount of uncertainty. The purpose of this study is to quantify the range uncertainty in various treatment conditions in proton therapy, using transmission measurements through various animal tissues. Animal tissues, including a pig head, beef steak, and lamb leg, were used in this study. For each tissue, an end-to-end test closely imitating patient treatments was performed. This included CT scan simulation, treatment planning, image-guided alignment, and beam delivery. Radio-chromic films were placed at various depths in the distal dose falloff region to measure depth dose. Comparisons between measured and calculated doses were used to evaluate range differences. The dose difference at the distal falloff between measurement and calculation depends on tissue type and treatment conditions. The estimated range difference was up to 5, 6 and 4 mm for the pig head, beef steak, and lamb leg irradiation, respectively. Our study shows that the TPS was able to calculate proton range within about 1.5% plus 1.5 mm. Accurate assessment of range uncertainty in treatment planning would allow better optimization of proton beam treatment, thus fully achieving proton beams’ superior dose advantage over conventional photon-based radiation therapy.

Photoacoustic and filter measurements related to aerosol light absorption during the Northern Front Range Air Quality Study (Colorado 1996/1997)

Science.gov (United States)

Moosmüller, H.; Arnott, W. P.; Rogers, C. F.; Chow, J. C.; Frazier, C. A.; Sherman, L. E.; Dietrich, D. L.

1998-11-01

A new photoacoustic instrument for the measurement of aerosol light absorption was collocated with conventional aerosol instrumentation during the 1996-1997 winter intensive monitoring period of the Northern Front Range Air Quality Study. Measurements of the light absorption efficiency for black carbon were 5 m2/g at 685 nm and 10 m2/g at 532 nm, and for elemental carbon, they were 3.6 m2/g at 685 nm. We show that these values together with previous photoacoustic measurements of aerosol light absorption shed some light on the wavelength dependence of absorption efficiency for carbonaceous aerosol in the visible and near-visible region. Integrating plate type filter measurements of aerosol light absorption result in far larger values than those measured with the photoacoustic instrument. We demonstrate that a recently published correction technique [Horvath, 1997] can yield improved agreement.

Coevolution of patch-type dependent emigration and patch-type dependent immigration.

Science.gov (United States)

Weigang, Helene C

2017-08-07

The three phases of dispersal - emigration, transfer and immigration - are affecting each other and the former and latter decisions may depend on patch types. Despite the inevitable fact of the complexity of the dispersal process, patch-type dependencies of dispersal decisions modelled as emigration and immigration are usually missing in theoretical dispersal models. Here, I investigate the coevolution of patch-type dependent emigration and patch-type dependent immigration in an extended Hamilton-May model. The dispersing population inhabits a landscape structured into many patches of two types and disperses during a continuous-time season. The trait under consideration is a four dimensional vector consisting of two values for emigration probability from the patches and two values for immigration probability into the patches of each type. Using the adaptive dynamics approach I show that four qualitatively different dispersal strategies may evolve in different parameter regions, including a counterintuitive strategy, where patches of one type are fully dispersed from (emigration probability is one) but individuals nevertheless always immigrate into them during the dispersal season (immigration probability is one). I present examples of evolutionary branching in a wide parameter range, when the patches with high local death rate during the dispersal season guarantee a high expected disperser output. I find that two dispersal strategies can coexist after evolutionary branching: a strategy with full immigration only into the patches with high expected disperser output coexists with a strategy that immigrates into any patch. Stochastic simulations agree with the numerical predictions. Since evolutionary branching is also found when immigration evolves alone, the present study is adding coevolutionary constraints on the emigration traits and hence finds that the coevolution of a higher dimensional trait sometimes hinders evolutionary diversification. Copyright © 2017

Studying the Complex Expression Dependences between Sets of Coexpressed Genes

Directory of Open Access Journals (Sweden)

Mario Huerta

2014-01-01

Full Text Available Organisms simplify the orchestration of gene expression by coregulating genes whose products function together in the cell. The use of clustering methods to obtain sets of coexpressed genes from expression arrays is very common; nevertheless there are no appropriate tools to study the expression networks among these sets of coexpressed genes. The aim of the developed tools is to allow studying the complex expression dependences that exist between sets of coexpressed genes. For this purpose, we start detecting the nonlinear expression relationships between pairs of genes, plus the coexpressed genes. Next, we form networks among sets of coexpressed genes that maintain nonlinear expression dependences between all of them. The expression relationship between the sets of coexpressed genes is defined by the expression relationship between the skeletons of these sets, where this skeleton represents the coexpressed genes with a well-defined nonlinear expression relationship with the skeleton of the other sets. As a result, we can study the nonlinear expression relationships between a target gene and other sets of coexpressed genes, or start the study from the skeleton of the sets, to study the complex relationships of activation and deactivation between the sets of coexpressed genes that carry out the different cellular processes present in the expression experiments.

Time-of-flight range imaging for underwater applications

Science.gov (United States)

Merbold, Hannes; Catregn, Gion-Pol; Leutenegger, Tobias

2018-02-01

Precise and low-cost range imaging in underwater settings with object distances on the meter level is demonstrated. This is addressed through silicon-based time-of-flight (TOF) cameras operated with light emitting diodes (LEDs) at visible, rather than near-IR wavelengths. We find that the attainable performance depends on a variety of parameters, such as the wavelength dependent absorption of water, the emitted optical power and response times of the LEDs, or the spectral sensitivity of the TOF chip. An in-depth analysis of the interplay between the different parameters is given and the performance of underwater TOF imaging using different visible illumination wavelengths is analyzed.

Cre-dependent DNA recombination activates a STING-dependent innate immune response

Science.gov (United States)

Pépin, Geneviève; Ferrand, Jonathan; Höning, Klara; Jayasekara, W. Samantha N.; Cain, Jason E.; Behlke, Mark A.; Gough, Daniel J.; G. Williams, Bryan R.; Hornung, Veit

2016-01-01

Abstract Gene-recombinase technologies, such as Cre/loxP-mediated DNA recombination, are important tools in the study of gene function, but have potential side effects due to damaging activity on DNA. Here we show that DNA recombination by Cre instigates a robust antiviral response in mammalian cells, independent of legitimate loxP recombination. This is due to the recruitment of the cytosolic DNA sensor STING, concurrent with Cre-dependent DNA damage and the accumulation of cytoplasmic DNA. Importantly, we establish a direct interplay between this antiviral response and cell–cell interactions, indicating that low cell densities in vitro could be useful to help mitigate these effects of Cre. Taking into account the wide range of interferon stimulated genes that may be induced by the STING pathway, these results have broad implications in fields such as immunology, cancer biology, metabolism and stem cell research. Further, this study sets a precedent in the field of gene-engineering, possibly applicable to other enzymatic-based genome editing technologies. PMID:27166376

Energy dependence of relative abundances and periods of delayed neutron separate groups from neutron induced fission of 239Pu in the virgin neutron energy range 0.37-4.97 MeV

International Nuclear Information System (INIS)

Piksajkin, V.M.; Kazakov, L.E.; Isaev, S.T.; Korolev, G.G.; Roshchenko, V.A.; Tertychnyj, R.G.

2002-01-01

Relative yield and group period of delayed neutrons induced by the 239 Pu fission in the 0.37-4.97 MeV range were measured. Comparative analysis of experimental data was conducted in terms of middle period of half-life of delayed neutron nuclei-precursors. Character and scale of changing values of delayed neutron group parameters as changing excitation energy of fission compound-nucleus have been demonstrated for the first time. Considerable energy dependence of group parameters under the neutron induced 239 Pu fission that was expressed by the decreasing middle period of half-life of nuclei-precursors by 10 % in the 2.85 eV - 5 MeV range of virgin neutrons was detected [ru

Dependence of O{sub 2} diffusion dynamics on pressure and temperature in silica nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Iovino, G., E-mail: giuseppe.iovino@unipa.it; Agnello, S., E-mail: simonpietro.agnello@unipa.it; Gelardi, F. M., E-mail: franco.gelardi@unipa.it [University of Palermo, Department of Physics and Chemistry (Italy)

2013-10-15

An experimental study of the molecular O{sub 2} diffusion process in high purity non-porous silica nanoparticles having 50 m{sup 2}/g BET specific surface and 20 nm average radius was carried out in the temperature range from 127 to 177 Degree-Sign C at O{sub 2} pressure in the range from 0.2 to 66 bar. The study was performed by measuring the volume average interstitial O{sub 2} concentration by a Raman and photoluminescence technique using a 1,064 nm excitation laser to detect the singlet to triplet emission at 1,272 nm of the molecular oxygen in silica. A dependence of the diffusion kinetics on the O{sub 2} absolute pressure, in addition to temperature dependence, was found. The kinetics can be fit by the solution of Fick's diffusion equation using an effective diffusion coefficient related to temperature and O{sub 2} external pressure. The fit results have evidenced that the temperature and pressure dependencies can be disentangled and that the pressure effects are more pronounced at lower temperatures. An Arrhenius temperature law is determined for the effective diffusion coefficient and the activation energy and pre-exponential factor are found in the explored experimental range. The reported findings have not been evidenced previously in the studies in bulk silica and could probably be originated by the reduced spatial extension of the considered system.

Thermophysical and thermodynamic properties of ionic liquids over an extended pressure range: [bmim][NTf2] and [hmim][NTf2

International Nuclear Information System (INIS)

Gomes de Azevedo, R.; Esperanca, J.M.S.S.; Szydlowski, J.; Visak, Z.P.; Pires, P.F.; Guedes, H.J.R.; Rebelo, L.P.N.

2005-01-01

The current study focuses on 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide, [bmim][NTf 2 ], and 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide, [hmim][NTf 2 ]. The objective is to study the influence of pressure as well as that of the cation's alkyl chain length on several properties of this type of ionic liquids. Speed of propagation of ultrasound waves and densities in pure ionic liquids (ILs) as a function of temperature and pressure have been determined. Several other thermodynamic properties such as compressibilities, expansivities and heat capacities have been obtained. Speed of sound measurements have been carried out in broad ranges of temperature (283 < T/K < 323) and pressure (0.1 < p/MPa < 150), using a non-intrusive microcell. Density measurements have been performed at broad ranges of temperature (298 < T/K < 333) and pressure (0.1 < p/MPa < 60) using a vibrating tube densimeter. The pressure dependence of heat capacities, which is generally mild, is highly dependent on the curvature of the temperature dependence of density

Micromechanical properties of C70 single crystals in the temperature range 77-350 K

International Nuclear Information System (INIS)

Lubenets, S.V.; Natsik, V.D.; Fomenko, L.S.; Rusakova, A.V.; Natsik, V.D.; Osip'yan, Yu.A.; Orlov, V.I.; Sidorov, N.S.; Izotov, A.N.

2012-01-01

Hexagonal single crystals of C 70 up to a size down to 1-2 mm were grown which allowed for the first time to investigate their low-temperature mechanical properties. Morphology, microplasticity anisotropy and the temperature dependence of Vickers microhardness HV (T) of the C 70 crystals in the temperature range 77-350 K involving all known phase transitions have been studied with the aid of optical microscopy and microindentation. The association of the features of HV (T) dependence with orientation phase transformations has been analyzed. It is suggested that anisotropy of microplasticity in the C 70 crystals correlates with the active slip systems.

Prediction of operating parameters range for ammonia removal unit in coke making by-products

Science.gov (United States)

Tiwari, Hari Prakash; Kumar, Rajesh; Bhattacharjee, Arunabh; Lingam, Ravi Kumar; Roy, Abhijit; Tiwary, Shambhu

2018-02-01

Coke oven gas treatment plants are well equipped with distributed control systems (DCS) and therefore recording the vast amount of operational data efficiently. Analyzing the stored information manually from historians is practically impossible. In this study, data mining technique was examined for lowering the ammonia concentration in clean coke oven gas. Results confirm that concentration of ammonia in clean coke oven gas depends on the average PCDC temperature; gas scrubber temperatures stripped liquor flow, stripped liquor concentration and stripped liquor temperature. The optimum operating ranges of the above dependent parameters using data mining technique for lowering the concentration of ammonia is described in this paper.

A detailed study of heat flow at the Fifth Water Site, Utah, in the Basin and Range-Colorado Plateaus transition

Science.gov (United States)

Powell, William G.; Chapman, David S.

1990-05-01

A detailed heat flow study has been conducted at a site in the southern Wasatch Mountains, Utah, in the thermal transition between the Colorado Plateau and Basin and Range tectonic provinces of the western U.S.A. Two wells, 600 m deep and only 400 m apart, in rugged terrain provided constraints on topographic and microclimatic effects and helped demonstrate the efficacy but also some inadequacies of commonly used heat flow corrections. Microclimatic effects changed the subsurface thermal gradients by up to 6%; atmospheric temperature lapse, insolation and vegetation all contribute about equally to the subsurface effects. The topographic disturbance decreased gradients by as much as 25%. Paleoclimate effects may decrease the heat flow by 7%, but the local paleoclimate is not well constrained and this value is uncertain. The rate of erosion in the Wasatch Mountains is also very poorly known, but is an important influence on the borehole temperature measurements. For reasonable bounds on the erosion rate of 0.1-1.0 mm y -1, acting over the past 10-20 My, the erosional history of the Wasatch Mountains contributes from 10% to 50% of the observed heat flow; lower values are more probable. The heat flow at Fifth Water is greater than 90 mW m -2, and possibly as high as 210 mW m -2, depending upon the paleoclimatic and erosional scenarios assumed. Our preferred value of corrected heat flow is 150 ± 10 mWm -2. This value is significantly higher than nearby heat flow determinations in both the Colorado Plateau and Basin and Range provinces, although well within the range of all Basin and Range heat flow estimates. Cooling of magma bodies in the upper crust and upwelling groundwater are unlikely mechanisms for the elevated heat flow at this site.

Analytical dependence of effective atomic number on the elemental composition of matter and radiation energy in the range 10-1000 keV

Science.gov (United States)

Eritenko, A. N.; Tsvetiansky, A. L.; Polev, A. A.

2018-01-01

In the present paper, a universal analytical dependence of effective atomic number on the composition of matter and radiation energy is proposed. This enables one to consider the case of a strong difference in the elemental composition with respect to their atomic numbers over a wide energy range. The contribution of photoelectric absorption and incoherent and coherent scattering during the interaction between radiation and matter is considered. For energy values over 40 keV, the contribution of coherent scattering does not exceed approximately 10% that can be neglected at a further consideration. The effective atomic numbers calculated on the basis of the proposed relationships are compared to the results of calculations based on other methods considered by different authors on the basis of experimental and tabulated data on mass and atomic attenuation coefficients. The examination is carried out for both single-element (e.g., 6C, 14Si, 28Cu, 56Ba, and 82Pb) and multi-element materials. Calculations are performed for W1-xCux alloys (x = 0.35; x = 0.4), PbO, ther moluminescent dosimetry compounds (56Ba, 48Cd, 41Sr, 20Ca, 12Mg, and 11Na), and SO4 in a wide energy range. A case with radiation energy between the K- and L1-absorption edges is considered for 82Pb, 74W, 56Ba, 48Cd, and 38Sr. This enables to substantially simplify the calculation of the atomic number and will be useful in technical and scientific fields related to the interaction between X-ray/gamma radiation and matter.

Hybrid gesture recognition system for short-range use

Science.gov (United States)

Minagawa, Akihiro; Fan, Wei; Katsuyama, Yutaka; Takebe, Hiroaki; Ozawa, Noriaki; Hotta, Yoshinobu; Sun, Jun

2012-03-01

In recent years, various gesture recognition systems have been studied for use in television and video games[1]. In such systems, motion areas ranging from 1 to 3 meters deep have been evaluated[2]. However, with the burgeoning popularity of small mobile displays, gesture recognition systems capable of operating at much shorter ranges have become necessary. The problems related to such systems are exacerbated by the fact that the camera's field of view is unknown to the user during operation, which imposes several restrictions on his/her actions. To overcome the restrictions generated from such mobile camera devices, and to create a more flexible gesture recognition interface, we propose a hybrid hand gesture system, in which two types of gesture recognition modules are prepared and with which the most appropriate recognition module is selected by a dedicated switching module. The two recognition modules of this system are shape analysis using a boosting approach (detection-based approach)[3] and motion analysis using image frame differences (motion-based approach)(for example, see[4]). We evaluated this system using sample users and classified the resulting errors into three categories: errors that depend on the recognition module, errors caused by incorrect module identification, and errors resulting from user actions. In this paper, we show the results of our investigations and explain the problems related to short-range gesture recognition systems.

The acoustical significance of age-dependent ear elongation

DEFF Research Database (Denmark)

Christensen, Flemming

2015-01-01

, corresponding to what is reported in the literature. For female ears, virtually no acoustical effect was found. For male ears directional dependent effects in the range up to 5 dB on average was found for certain directions and frequencies. Implications on age dependent hearing loss (presbycusis...

Entanglement and quantum state geometry of a spin system with all-range Ising-type interaction

Science.gov (United States)

Kuzmak, A. R.

2018-04-01

The evolution of an N spin-1/2 system with all-range Ising-type interaction is considered. For this system we study the entanglement of one spin with the rest spins. It is shown that the entanglement depends on the number of spins and the initial state. Also, the geometry of the manifold, which contains entangled states, is obtained. For this case we find the dependence of entanglement on the scalar curvature of the manifold and examine it for different numbers of spins in the system. Finally we show that the transverse magnetic field leads to a change in the manifold topology.

EXECUTIVE DYSFUNCTION IN ALCOHOL DEPENDENT INDIVIDUALS: A CASE CONTROL STUDY

Directory of Open Access Journals (Sweden)

Neethi Valsan

2016-06-01

Full Text Available BACKGROUND The use of alcohol is increasingly prevalent in our country. Being a neurotoxin, it tends to affect elective mental capacities. Frontal lobe is found to be most affected by chronic alcohol use. AIM To study the executive functions in alcohol dependent individuals and to determine any relationship with alcohol intake variables. MATERIALS AND METHODS 30 recently detoxified alcohol dependent individuals attending the De-addiction Clinic of Medical College, Kottayam, was compared to 30 controls on four tests of executive functions, namely, Controlled Word Association Test, Trail Making Test, Stroop Test, and Wisconsin Card Sorting Test. Statistical analysis of the data has been done using the Statistical Package for Social Sciences (SPSS Windows version 10. RESULTS Executive function was significantly impaired in the alcohol dependent individuals when compared to normal controls in all the four tests. On analysing the effect of drinking variables on executive functioning, the performance of patients is seen to improve with abstinence in Stroop. Those with a positive family history of ADS in the first degree relatives produced fewer words in verbal fluency. CONCLUSION As the executive impairment remains more or less stable irrespective to the chronicity or amount of alcohol use, it could be assumed that the executive dysfunction observed is a trait marker rather than a state dependent variable.

Dielectric relaxation in solid collagen over a wide temperature range

International Nuclear Information System (INIS)

Khan, Muhammad Abdullah; Rizvi, Tasneem Zahra; Janjua, Khalid Mehmood; Zaheer, Muhammad Yar

2001-07-01

Dielectric constant ε' and loss factor ε'' have been measured in bovine tendon collagen in the frequency range 30 Hz - 3 MHz and temperature range 30 deg. C to 200 deg. C. Frequency dependence curve of ε'' shows a low frequency strong α-dispersion attributed to phonon assisted proton hopping between localized sites and a weak high frequency. α 2 - dispersion attributed to reorientation of polar components of collagen molecules. Temperature dependence of the dielectric data show release of bound moisture as a three step process with discrete peaks at 50 deg. C, 90 deg. C and 125 deg. C. These peaks have been attributed to release of adsorbed surface water, water bound to exposed polar sites and strongly bound internal moisture respectively. A peak observed at 160 deg. C has been attributed to thermally induced helix-coil transition of collagen molecules. (author)

Generalized Cauchy model of sea level fluctuations with long-range dependence

Science.gov (United States)

Li, Ming; Li, Jia-Yue

2017-10-01

This article suggests the contributions with two highlights. One is to propose a novel model of sea level fluctuations (sea level for short), which is called the generalized Cauchy (GC) process. It provides a new outlook for the description of local and global behaviors of sea level from a view of fractal in that the fractal dimension D that measures the local behavior of sea level and the Hurst parameter H which characterizes the global behavior of sea level are independent of each other. The other is to show that sea level appears multi-fractal in both spatial and time. Such a meaning of multi-fractal is new in the sense that a pair of fractal parameters (D, H) of sea level is varying with measurement sites and time. This research exhibits that the ranges of D and H of sea level, in general, are 1 ≤ D sea level, we shall show that H > 0 . 96 for all data records at all measurement sites, implying that strong LRD may be a general phenomenon of sea level. On the other side, regarding with the local behavior, we will reveal that there appears D = 1 or D ≈ 1 for data records at a few stations and at some time, but D > 0 . 96 at most stations and at most time, meaning that sea level may appear highly local irregularity more frequently than weak local one.

Structural study of surfactant-dependent interaction with protein

Energy Technology Data Exchange (ETDEWEB)

Mehan, Sumit; Aswal, Vinod K., E-mail: vkaswal@barc.gov.in [Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Kohlbrecher, Joachim [Laboratory for Neutron Scattering, Paul Scherrer Institut, CH-5232 PSI Villigen (Switzerland)

2015-06-24

Small-angle neutron scattering (SANS) has been used to study the complex structure of anionic BSA protein with three different (cationic DTAB, anionic SDS and non-ionic C12E10) surfactants. These systems form very different surfactant-dependent complexes. We show that the structure of protein-surfactant complex is initiated by the site-specific electrostatic interaction between the components, followed by the hydrophobic interaction at high surfactant concentrations. It is also found that hydrophobic interaction is preferred over the electrostatic interaction in deciding the resultant structure of protein-surfactant complexes.

Sensitivity analysis of time-dependent laminar flows

International Nuclear Information System (INIS)

Hristova, H.; Etienne, S.; Pelletier, D.; Borggaard, J.

2004-01-01

This paper presents a general sensitivity equation method (SEM) for time dependent incompressible laminar flows. The SEM accounts for complex parameter dependence and is suitable for a wide range of problems. The formulation is verified on a problem with a closed form solution obtained by the method of manufactured solution. Systematic grid convergence studies confirm the theoretical rates of convergence in both space and time. The methodology is then applied to pulsatile flow around a square cylinder. Computations show that the flow starts with symmetrical vortex shedding followed by a transition to the traditional Von Karman street (alternate vortex shedding). Simulations show that the transition phase manifests itself earlier in the sensitivity fields than in the flow field itself. Sensitivities are then demonstrated for fast evaluation of nearby flows and uncertainty analysis. (author)

Retrieval interval mapping, a tool to optimize the spectral retrieval range in differential optical absorption spectroscopy

Science.gov (United States)

Vogel, L.; Sihler, H.; Lampel, J.; Wagner, T.; Platt, U.

2012-06-01

Remote sensing via differential optical absorption spectroscopy (DOAS) has become a standard technique to identify and quantify trace gases in the atmosphere. The technique is applied in a variety of configurations, commonly classified into active and passive instruments using artificial and natural light sources, respectively. Platforms range from ground based to satellite instruments and trace-gases are studied in all kinds of different environments. Due to the wide range of measurement conditions, atmospheric compositions and instruments used, a specific challenge of a DOAS retrieval is to optimize the parameters for each specific case and particular trace gas of interest. This becomes especially important when measuring close to the detection limit. A well chosen evaluation wavelength range is crucial to the DOAS technique. It should encompass strong absorption bands of the trace gas of interest in order to maximize the sensitivity of the retrieval, while at the same time minimizing absorption structures of other trace gases and thus potential interferences. Also, instrumental limitations and wavelength depending sources of errors (e.g. insufficient corrections for the Ring effect and cross correlations between trace gas cross sections) need to be taken into account. Most often, not all of these requirements can be fulfilled simultaneously and a compromise needs to be found depending on the conditions at hand. Although for many trace gases the overall dependence of common DOAS retrieval on the evaluation wavelength interval is known, a systematic approach to find the optimal retrieval wavelength range and qualitative assessment is missing. Here we present a novel tool to determine the optimal evaluation wavelength range. It is based on mapping retrieved values in the retrieval wavelength space and thus visualize the consequence of different choices of retrieval spectral ranges, e.g. caused by slightly erroneous absorption cross sections, cross correlations and

Hydration-dependent dynamics of human telomeric oligonucleotides in the picosecond timescale: A neutron scattering study

Energy Technology Data Exchange (ETDEWEB)

Sebastiani, F.; Comez, L.; Sacchetti, F. [Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, Via A. Pascoli, 06123 Perugia (Italy); CNR, Istituto Officina dei Materiali, Unità di Perugia, c/o Dipartimento di Fisica e Geologia, Università di Perugia, 06123 Perugia (Italy); Longo, M. [Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, Via A. Pascoli, 06123 Perugia (Italy); Elettra—Sincrotrone Trieste, 34149 Basovizza, Trieste (Italy); Orecchini, A.; Petrillo, C.; Paciaroni, A., E-mail: alessandro.paciaroni@fisica.unipg.it [Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, Via A. Pascoli, 06123 Perugia (Italy); De Francesco, A. [CNR-IOM OGG c/o Institut Laue-Langevin, 71 Avenue des Martyrs, CS20156, 38042 Grenoble Cedex 9 (France); Muthmann, M. [Jülich Centre for Neutron Science, Forschungszentrum Jülich GmbH, Outstation at Heinz Maier-Leibnitz Zentrum, Lichtenbergstrasse 1, 85747 Garching (Germany); Teixeira, S. C. M. [EPSAM, Keele University, Staffordshire ST5 5BG (United Kingdom); Institut Laue–Langevin, 71 Avenue des Martyrs, CS20156, 38042 Grenoble Cedex 9 (France)

2015-07-07

The dynamics of the human oligonucleotide AG{sub 3}(T{sub 2}AG{sub 3}){sub 3} has been investigated by incoherent neutron scattering in the sub-nanosecond timescale. A hydration-dependent dynamical activation of thermal fluctuations in weakly hydrated samples was found, similar to that of protein powders. The amplitudes of such thermal fluctuations were evaluated in two different exchanged wave-vector ranges, so as to single out the different contributions from intra- and inter-nucleotide dynamics. The activation energy was calculated from the temperature-dependent characteristic times of the corresponding dynamical processes. The trends of both amplitudes and activation energies support a picture where oligonucleotides possess a larger conformational flexibility than long DNA sequences. This additional flexibility, which likely results from a significant relative chain-end contribution to the average chain dynamics, could be related to the strong structural polymorphism of the investigated oligonucleotides.

Home range and travels

Science.gov (United States)

Stickel, L.F.; King, John A.

1968-01-01

The concept of home range was expressed by Seton (1909) in the term 'home region,' which Burr (1940, 1943) clarified with a definition of home range and exemplified in a definitive study of Peromyscus in the field. Burt pointed out the ever-changing characteristics of home-range area and the consequent absence of boundaries in the usual sense--a finding verified by investigators thereafter. In the studies summarized in this paper, sizes of home ranges of Peromyscus varied within two magnitudes, approximately from 0.1 acre to ten acres, in 34 studies conducted in a variety of habitats from the seaside dunes of Florida to the Alaskan forests. Variation in sizes of home ranges was correlated with both environmental and physiological factors; with habitat it was conspicuous, both in the same and different regions. Food supply also was related to size of home range, both seasonally and in relation to habitat. Home ranges generally were smallest in winter and largest in spring, at the onset of the breeding season. Activity and size also were affected by changes in weather. Activity was least when temperatures were low and nights were bright. Effects of rainfall were variable. Sizes varied according to sex and age; young mice remained in the parents' range until they approached maturity, when they began to travel more widely. Adult males commonly had larger home ranges than females, although there were a number of exceptions. An inverse relationship between population density and size of home range was shown in several studies and probably is the usual relationship. A basic need for activity and exploration also appeared to influence size of home range. Behavior within the home range was discussed in terms of travel patterns, travels in relation to home sites and refuges, territory, and stability of size of home range. Travels within the home range consisted of repeated use of well-worn trails to sites of food, shelter, and refuge, plus more random exploratory travels

Study of energy dependence of a extrapolation chamber in low energy X-rays beams

International Nuclear Information System (INIS)

Bastos, Fernanda M.; Silva, Teogenes A. da

2014-01-01

This work was with the main objective to study the energy dependence of extrapolation chamber in low energy X-rays to determine the value of the uncertainty associated with the variation of the incident radiation energy in the measures in which it is used. For studying the dependence of energy, were conducted comparative ionization current measurements between the extrapolation chamber and two ionization chambers: a chamber mammography, RC6M model, Radcal with energy dependence less than 5% and a 2575 model radioprotection chamber NE Technology; both chambers have very thin windows, allowing its application in low power beams. Measurements were made at four different depths of 1.0 to 4.0 mm extrapolation chamber, 1.0 mm interval, for each reference radiation. The study showed that there is a variable energy dependence on the volume of the extrapolation chamber. In other analysis, it is concluded that the energy dependence of extrapolation chamber becomes smaller when using the slope of the ionization current versus depth for the different radiation reference; this shows that the extrapolation technique, used for the absorbed dose calculation, reduces the uncertainty associated with the influence of the response variation with energy radiation

Folding of polymer chains with short-range binormal interactions

International Nuclear Information System (INIS)

Craig, A; Terentjev, E M

2006-01-01

We study the structure of chains which have anisotropic short-range contact interactions that depend on the alignment of the binormal vectors of chain segments. This represents a crude model of hydrogen bonding or 'stacking' interactions out of the plane of curvature. The polymers are treated as ribbon-like semi-flexible chains, where the plane of the ribbon is determined by the local binormal. We show that with dipole-dipole interactions between the binormals of contacting chain segments, mean-field theory predicts a first-order transition to a binormally aligned state. We describe the onset of this transition as a function of the temperature-dependent parameters that govern the chain stiffness and the strength of the binormal interaction, as well as the binormal alignment's coupling to chain collapse. We also examine a metastable state governing the folding kinetics. Finally, we discuss the possible mesoscopic structure of the aligned phase, and application of our model to secondary structure motifs like β-sheets and α-helices, as well as composite structures like β-(amyloid) fibrils

Psilocybin-assisted treatment for alcohol dependence: a proof-of-concept study.

Science.gov (United States)

Bogenschutz, Michael P; Forcehimes, Alyssa A; Pommy, Jessica A; Wilcox, Claire E; Barbosa, P C R; Strassman, Rick J

2015-03-01

Several lines of evidence suggest that classic (5HT2A agonist) hallucinogens have clinically relevant effects in alcohol and drug addiction. Although recent studies have investigated the effects of psilocybin in various populations, there have been no studies on the efficacy of psilocybin for alcohol dependence. We conducted a single-group proof-of-concept study to quantify acute effects of psilocybin in alcohol-dependent participants and to provide preliminary outcome and safety data. Ten volunteers with DSM-IV alcohol dependence received orally administered psilocybin in one or two supervised sessions in addition to Motivational Enhancement Therapy and therapy sessions devoted to preparation for and debriefing from the psilocybin sessions. Participants' responses to psilocybin were qualitatively similar to those described in other populations. Abstinence did not increase significantly in the first 4 weeks of treatment (when participants had not yet received psilocybin), but increased significantly following psilocybin administration (p psilocybin session (at week 4) strongly predicted change in drinking during weeks 5-8 (r = 0.76 to r = 0.89) and also predicted decreases in craving and increases in abstinence self-efficacy during week 5. There were no significant treatment-related adverse events. These preliminary findings provide a strong rationale for controlled trials with larger samples to investigate efficacy and mechanisms. NCT02061293. © The Author(s) 2015.

Neuronavigation accuracy dependence on CT and MR imaging parameters: a phantom-based study

International Nuclear Information System (INIS)

Poggi, S; Pallotta, S; Russo, S; Gallina, P; Torresin, A; Bucciolini, M

2003-01-01

Clinical benefits from neuronavigation are well established. However, the complexity of its technical environment requires a careful evaluation of different types of errors. In this work, a detailed phantom study which investigates the accuracy in a neuronavigation procedure is presented. The dependence on many different imaging parameters, such as field of view, slice thickness and different kind of sequences (sequential and spiral for CT, T1-weighted and T2-weighted for MRI), is quantified. Moreover, data based on CT images are compared to those based on MR images, taking into account MRI distortion. Finally, the contributions to global accuracy coming from image acquisition, registration and navigation itself are discussed. Results demonstrate the importance of imaging accuracy. Procedures based on CT proved to be more accurate than procedures based on MRI. In the former, values from 2 to 2.5 mm are obtained for 95% fractiles of cumulative distribution of Euclidean distances between the intended target and the reached one while, in the latter, the measured values range from 3 to 4 mm. The absence of imaging distortion proved to be crucial for registration accuracy in MR-based procedures

In Vivo Quantitative Study of Sized-Dependent Transport and Toxicity of Single Silver Nanoparticles Using Zebrafish Embryos

Science.gov (United States)

Lee, Kerry J.; Browning, Lauren M.; Nallathamby, Prakash D.; Desai, Tanvi; Cherukui, Pavan K.; Xu, Xiao-Hong Nancy

2012-01-01

Nanomaterials possess distinctive physicochemical properties (e.g., small sizes, high surface area-to-volume ratios) and promise a wide variety of applications, ranging from design of high quality consumer products to effective disease diagnosis and therapy. These properties can lead to toxic effects, potentially hindering advance in nanotechnology. In this study, we have synthesized and characterized purified and stable (non-aggregation) silver nanoparticles (Ag NPs, 41.6±9.1 nm in average diameters), and utilized early-developing (cleavage-stage) zebrafish embryos (critical aquatic and eco- species) as in vivo model organisms to probe diffusion and toxicity of Ag NPs. We found that single Ag NPs (30–72 nm diameters) passively diffused into the embryos through chorionic pores via random Brownian motion and stayed inside the embryos throughout their entire development (120 hours-post-fertilization, hpf). Dose and size dependent toxic effects of the NPs on embryonic development were observed, showing the possibility of tuning biocompatibility and toxicity of the NPs. At lower concentrations of the NPs (≤ 0.02 nM), 75–91% of embryos developed to normal zebrafish. At the higher concentrations of NPs (≥ 0.20 nM), 100% of embryos became dead. At the concentrations in between (0.02–0.2 nM), embryos developed to various deformed zebrafish. Number and sizes of individual Ag NPs embedded in tissues of normal and deformed zebrafish at 120 hpf were quantitatively analyzed, showing deformed zebrafish with higher number of larger NPs than normal zebrafish, and size-dependent nanotoxicity. By comparing with our previous studies of smaller Ag NPs (11.6±3.5 nm), the results further demonstrate striking size-dependent nanotoxicity that, at the same molar concentration, the larger Ag NPs (41.6±9.1 nm) are more toxic than the smaller Ag NPs (11.6±3.5 nm). PMID:22486336

Phase-Angle Dependence of Determinations of Diameter, Albedo, and Taxonomy: A Case Study of NEO 3691 Bede

Science.gov (United States)

Wooden, Diane H.; Lederer, Susan M.; Jehin, Emmanuel; Howell, Ellen S.; Fernandez, Yan; Harker, David E.; Ryan, Erin; Lovell, Amy; Woodward, Charles E.; Benner, Lance A.

2015-01-01

Parameters important for NEO risk assessment and mitigation include Near-Earth Object diameter and taxonomic classification, which translates to surface composition. Diameters of NEOs are derived from the thermal fluxes measured by WISE, NEOWISE, Spitzer Warm Mission and ground-based telescopes including the IRTF and UKIRT. Diameter and its coupled parameters Albedo and IR beaming parameter (a proxy for thermal inertia and/or surface roughness) are dependent upon the phase angle, which is the Sun-target-observer angle. Orbit geometries of NEOs, however, typically provide for observations at phase angles greater than 20 degrees. At higher phase angles, the observed thermal emission is sampling both the day and night sides of the NEO. We compare thermal models for NEOs that exclude (NEATM) and include (NESTM) night-side emission. We present a case study of NEO 3691 Bede, which is a higher albedo object, X (Ec) or Cgh taxonomy, to highlight the range of H magnitudes for this object (depending on the albedo and phase function slope parameter G), and to examine at different phase angles the taxonomy and thermal model fits for this NEO. Observations of 3691 Bede include our observations with IRTF+SpeX and with the 10 micrometer UKIRT+Michelle instrument, as well as WISE and Spitzer Warm mission data. By examining 3691 Bede as a case study, we highlight the interplay between the derivation of basic physical parameters and observing geometry, and we discuss the uncertainties in H magnitude, taxonomy assignment amongst the X-class (P, M, E), and diameter determinations. Systematic dependencies in the derivation of basic characterization parameters of H-magnitude, diameter, albedo and taxonomy with observing geometry are important to understand. These basic characterization parameters affect the statistical assessments of the NEO population, which in turn, affects the assignment of statistically-assessed basic parameters to discovered but yet-to-be-fully-characterized NEOs.

Guided transmission of highly charged ions through nanocapillaries in PET. Study of the energy dependencies

International Nuclear Information System (INIS)

Helhammer, R.; Pesic, Z.D.; Sobocinski, P.; Bundesmann, J.; Fink, D.; Stolterfoht, N.; Sulik, B.

2004-01-01

Full text: Recently we reported experiments in which slow highly charged ions are transmitted through nanocapillaries of 100nm diameter in an insulating PET foil of 10μm thickness [1]. The results of this work differ significantly from previous studies, which have been focused on capillaries in metals [2]. We measured the transmission of 3 keV Ne 7+ ions through the capillaries and focused the attention on ions whose charge has not changed during the passage through the capillary. The observation that the angular distribution for PET has a peak maximum whose position is equal to the tilt angle indicates a guiding of the Ne 7+ ion within the capillary. This guiding shows that the inner walls of the capillaries are charged up in a self-organizing process and collisions with the surface are finally prevented. We studied the time evolution of the capillary guiding as well as dependencies on the tilt angle [3]. Our most recent measurements were focussed on the investigation of the energy dependency for the guiding of Ne 7+ through capillaries. The measurements were done in an energy range from 2 keV up to 10 keV.We measured higher guiding efficiency for lower energies consistent with a previously developed model, which predicted an increase of the guiding efficiency with decreasing projectile energy [3]. In addition we found the effect of a narrower width of the angular distribution of transmitted ions. This effect is also well described by the model. However, further work is needed to explain the amount of charges to build up the deflection field at the end of the capillaries

Studying the collision energy dependence of elliptic and triangular flow with a hybrid model

Energy Technology Data Exchange (ETDEWEB)

Auvinen, Jussi [Frankfurt Institute for Advanced Studies, Frankfurt am Main (Germany); Petersen, Hannah [Frankfurt Institute for Advanced Studies, Frankfurt am Main (Germany); Institut fuer Theoretische Physik, Goethe Universitaet, Frankfurt am Main (Germany)

2014-07-01

Elliptic flow has been one of the key observables for establishing the finding of the quark-gluon plasma (QGP) at the highest energies of Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC). As a sign of collectively behaving matter, the elliptic flow is expected to decrease at lower beam energies, where the QGP is not produced. However, in the recent RHIC beam energy scan, it has been found that the inclusive charged hadron elliptic flow changes relatively little in magnitude within the energy range 7.7-39 GeV per nucleon-nucleon collision. We study the collision energy dependence of the elliptic and triangular flow utilizing a Boltzmann+hydrodynamics hybrid model. Such a hybrid model provides a natural framework for the transition from high collision energies, where the hydrodynamical description is essential, to smaller energies, where the hadron transport dominates. This approach is thus suitable for investigating the relative importance of these two mechanisms for the production of the collective flow at different beam energies.

Dependency and self-criticism in post-partum depression and anxiety: a case control study.

Science.gov (United States)

Vliegen, Nicole; Luyten, Patrick

2009-01-01

This study investigates the role of self-criticism and dependency in inpatient post-partum depressed women (n = 55) and non-depressed controls (n = 37) as well as the relationship between both personality dimensions and severity of depression and anxiety. As expected, mothers with post-partum depression showed not only increased levels of depression but also anxiety compared with non-depressed mothers. Furthermore, they had significantly higher levels of self-criticism, but not of dependency. In the post-partum depressed mothers, both personality dimensions were positively associated with severity of depression. However, in non-depressed mothers, self-criticism was positively associated with depression, while there was an inverse relationship between dependency and severity of depression. In both samples, self-criticism, but not dependency, was related to state anxiety. The cross-sectional nature of this study limits the ability to draw causal conclusions. The study was based on self-report and conducted in relatively small samples.

Thickness-dependent change in the valence band offset of the SiO{sub 2}/Si interface studied using synchrotron-radiation photoemission spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Toyoda, S., E-mail: toyoda.satoshi.4w@kyoto-u.ac.jp; Oshima, M. [Department of Applied Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656 (Japan)

2016-08-28

We have studied the thickness-dependent change in the valence band offset (VBO) of the SiO{sub 2}/Si(001) interface using synchrotron-radiation photoemission spectroscopy with soft and hard X-rays. The SiO{sub 2}-film thickness (T{sub ox}) and X-ray irradiation time (t{sub irrad}) were systematically parameterized to distinguish between the “intrinsic” T{sub ox} effects in the VBOs and the “extrinsic” differential charging phenomena in SiO{sub 2} films on Si substrates. The results revealed that at a spontaneous time (t{sub irrad} ≈ 5 s) that suppresses the differential charging phenomena as much as possible, the experimental VBO abruptly increases as a function of T{sub ox} and gradually saturates to the traditional VBO value range determined by the internal photoemission and photoconduction measurements. This effect is not attributed to the differential charging phenomena, but rather it is attributed to the “intrinsic” T{sub ox}-dependent change in the VBO. The two possible physical behaviors include electronic polarization and image charge. We have derived the electronic polarization contribution from experimental data by carefully describing the effects of the long-range image charges based on the classical dielectric-screening model.

A Preliminary Study of Sexual Dysfunction in Male Opioid-Dependants under Methadone Maintenance Treatment

Directory of Open Access Journals (Sweden)

Masoudeh Babakhanian

2011-08-01

Full Text Available Introduction: Sexual dysfunction is one of the prevalent problems of opiate-dependent patients. The current preliminarily study examines sexual dysfunction in a group of opiate-dependent patients before and after 6 months of MMT. Methods: The current study is a cross-sectional study. The numbers of 30 opiate-dependent patients were selected of Cheraghiyan clinic in Damghan, Iran. Demographics questionnaire and the International Index of Erectile Function were administered before and after treatment. Results: Erectile function showed an increase and intercourse satisfactions completely improved. Sexual desire and overall satisfaction increased, showing slight improvement while orgasmic function increased showing no improvement. Discussion: The findings revealed the prevalence of sexual dysfunction and improvement of some component in patients after treatment. Future studies are needed to explore the roles of other factors.

Ionizing acceleration of color center transformation in the low radiation dose range

International Nuclear Information System (INIS)

Mamontov, A.P.; Starodubtsev, V.A.; Chernov, I.P.

1985-01-01

The purpose of the study is investigation of annealing and colour centers transformation of known nature in lithium fluoride crystals at the γ-irradiation low doses. The controlled colour centers have been introduced by LiF monocrystal samples irradiation by protons with 6 MeV energy. The γ-radiation dose rate constitutes 25 Grxssup(-1). The variation of absorption spectra caused by proton and γ-irradiation in initial crystals and in the sample being twice exposed has been studied. It is shown that for LiF monocrystals in the γ-radiation low dose range (below 5 kGr) anomalous dependences of concentration of F-aggregate colour centers on the irradiation dose are observed. High efficiency in defects transformation can be caused by the chain of self-sustaining reactions. The observed N-type dependences caused defects decay and competition of the processes of capture of anionic vacancies by F- and F-aggregate centers

Time-dependent histamine release from stored human blood products

DEFF Research Database (Denmark)

Nielsen, Hans Jørgen; Edvardsen, L; Vangsgaard, K

1996-01-01

.0 (range 176.0-910.0) nmol/l in whole blood and 475.0 (range 360.0-1560.0) nmol/l in plasma-reduced whole blood, while it was undetectable in SAGM blood. Spontaneous histamine release increased in a time-dependent manner from a median of 6.7 (range 2.2-17.4) nmol/l at the time of storage to 175.0 (range 33...

Monte Carlo patient study on the comparison of prompt gamma and PET imaging for range verification in proton therapy

Science.gov (United States)

Moteabbed, M.; España, S.; Paganetti, H.

2011-02-01

The purpose of this work was to compare the clinical adaptation of prompt gamma (PG) imaging and positron emission tomography (PET) as independent tools for non-invasive proton beam range verification and treatment validation. The PG range correlation and its differences with PET have been modeled for the first time in a highly heterogeneous tissue environment, using different field sizes and configurations. Four patients with different tumor locations (head and neck, prostate, spine and abdomen) were chosen to compare the site-specific behaviors of the PG and PET images, using both passive scattered and pencil beam fields. Accurate reconstruction of dose, PG and PET distributions was achieved by using the planning computed tomography (CT) image in a validated GEANT4-based Monte Carlo code capable of modeling the treatment nozzle and patient anatomy in detail. The physical and biological washout phenomenon and decay half-lives for PET activity for the most abundant isotopes such as 11C, 15O, 13N, 30P and 38K were taken into account in the data analysis. The attenuation of the gamma signal after traversing the patient geometry and respective detection efficiencies were estimated for both methods to ensure proper comparison. The projected dose, PG and PET profiles along many lines in the beam direction were analyzed to investigate the correlation consistency across the beam width. For all subjects, the PG method showed on average approximately 10 times higher gamma production rates than the PET method before, and 60 to 80 times higher production after including the washout correction and acquisition time delay. This rate strongly depended on tissue density and elemental composition. For broad passive scattered fields, it was demonstrated that large differences exist between PG and PET signal falloff positions and the correlation with the dose distribution for different lines in the beam direction. These variations also depended on the treatment site and the

Multi-GNSS signal-in-space range error assessment - Methodology and results

Science.gov (United States)

Montenbruck, Oliver; Steigenberger, Peter; Hauschild, André

2018-06-01

The positioning accuracy of global and regional navigation satellite systems (GNSS/RNSS) depends on a variety of influence factors. For constellation-specific performance analyses it has become common practice to separate a geometry-related quality factor (the dilution of precision, DOP) from the measurement and modeling errors of the individual ranging measurements (known as user equivalent range error, UERE). The latter is further divided into user equipment errors and contributions related to the space and control segment. The present study reviews the fundamental concepts and underlying assumptions of signal-in-space range error (SISRE) analyses and presents a harmonized framework for multi-GNSS performance monitoring based on the comparison of broadcast and precise ephemerides. The implications of inconsistent geometric reference points, non-common time systems, and signal-specific range biases are analyzed, and strategies for coping with these issues in the definition and computation of SIS range errors are developed. The presented concepts are, furthermore, applied to current navigation satellite systems, and representative results are presented along with a discussion of constellation-specific problems in their determination. Based on data for the January to December 2017 time frame, representative global average root-mean-square (RMS) SISRE values of 0.2 m, 0.6 m, 1 m, and 2 m are obtained for Galileo, GPS, BeiDou-2, and GLONASS, respectively. Roughly two times larger values apply for the corresponding 95th-percentile values. Overall, the study contributes to a better understanding and harmonization of multi-GNSS SISRE analyses and their use as key performance indicators for the various constellations.

Communication: Anomalous temperature dependence of the intermediate range order in phosphonium ionic liquids

International Nuclear Information System (INIS)

Hettige, Jeevapani J.; Kashyap, Hemant K.; Margulis, Claudio J.

2014-01-01

In a recent article by the Castner and Margulis groups [Faraday Discuss. 154, 133 (2012)], we described in detail the structure of the tetradecyltrihexylphosphonium bis(trifluoromethylsulfonyl)-amide ionic liquid as a function of temperature using X-ray scattering, and theoretical partitions of the computationally derived structure function. Interestingly, and as opposed to the case in most other ionic-liquids, the first sharp diffraction peak or prepeak appears to increase in intensity as temperature is increased. This phenomenon is counter intuitive as one would expect that intermediate range order fades as temperature increases. This Communication shows that a loss of hydrophobic tail organization at higher temperatures is counterbalanced by better organization of polar components giving rise to the increase in intensity of the prepeak

Temperature dependence of the electrical resistivity of amorphous Co80-xErxB20 alloys

International Nuclear Information System (INIS)

Touraghe, O.; Khatami, M.; Menny, A.; Lassri, H.; Nouneh, K.

2008-01-01

The temperature dependence of the electrical resistivity of amorphous Co 80-x Er x B 20 alloys with x=0, 3.9, 7.5 and 8.6 prepared by melt spinning in pure argon atmosphere was studied. All amorphous alloys investigated here are found to exhibit a resistivity minimum at low temperature. The electrical resistivity exhibits logarithmic temperature dependence below the temperature of resistivity minimum T min . In addition, the resistivity shows quadratic temperature behavior in the interval T min < T<77 K. At high temperature, the electrical resistivity was discussed by the extended Ziman theory. For the whole series of alloys, the composition dependence of the temperature coefficient of electrical resistivity α shows a change in structural short range occurring in the composition range 8-9 at%

A stochastic chemical dynamic approach to correlate autoimmunity and optimal vitamin-D range.

Science.gov (United States)

Roy, Susmita; Shrinivas, Krishna; Bagchi, Biman

2014-01-01

Motivated by several recent experimental observations that vitamin-D could interact with antigen presenting cells (APCs) and T-lymphocyte cells (T-cells) to promote and to regulate different stages of immune response, we developed a coarse grained but general kinetic model in an attempt to capture the role of vitamin-D in immunomodulatory responses. Our kinetic model, developed using the ideas of chemical network theory, leads to a system of nine coupled equations that we solve both by direct and by stochastic (Gillespie) methods. Both the analyses consistently provide detail information on the dependence of immune response to the variation of critical rate parameters. We find that although vitamin-D plays a negligible role in the initial immune response, it exerts a profound influence in the long term, especially in helping the system to achieve a new, stable steady state. The study explores the role of vitamin-D in preserving an observed bistability in the phase diagram (spanned by system parameters) of immune regulation, thus allowing the response to tolerate a wide range of pathogenic stimulation which could help in resisting autoimmune diseases. We also study how vitamin-D affects the time dependent population of dendritic cells that connect between innate and adaptive immune responses. Variations in dose dependent response of anti-inflammatory and pro-inflammatory T-cell populations to vitamin-D correlate well with recent experimental results. Our kinetic model allows for an estimation of the range of optimum level of vitamin-D required for smooth functioning of the immune system and for control of both hyper-regulation and inflammation. Most importantly, the present study reveals that an overdose or toxic level of vitamin-D or any steroid analogue could give rise to too large a tolerant response, leading to an inefficacy in adaptive immune function.

A stochastic chemical dynamic approach to correlate autoimmunity and optimal vitamin-D range.

Directory of Open Access Journals (Sweden)

Susmita Roy

Full Text Available Motivated by several recent experimental observations that vitamin-D could interact with antigen presenting cells (APCs and T-lymphocyte cells (T-cells to promote and to regulate different stages of immune response, we developed a coarse grained but general kinetic model in an attempt to capture the role of vitamin-D in immunomodulatory responses. Our kinetic model, developed using the ideas of chemical network theory, leads to a system of nine coupled equations that we solve both by direct and by stochastic (Gillespie methods. Both the analyses consistently provide detail information on the dependence of immune response to the variation of critical rate parameters. We find that although vitamin-D plays a negligible role in the initial immune response, it exerts a profound influence in the long term, especially in helping the system to achieve a new, stable steady state. The study explores the role of vitamin-D in preserving an observed bistability in the phase diagram (spanned by system parameters of immune regulation, thus allowing the response to tolerate a wide range of pathogenic stimulation which could help in resisting autoimmune diseases. We also study how vitamin-D affects the time dependent population of dendritic cells that connect between innate and adaptive immune responses. Variations in dose dependent response of anti-inflammatory and pro-inflammatory T-cell populations to vitamin-D correlate well with recent experimental results. Our kinetic model allows for an estimation of the range of optimum level of vitamin-D required for smooth functioning of the immune system and for control of both hyper-regulation and inflammation. Most importantly, the present study reveals that an overdose or toxic level of vitamin-D or any steroid analogue could give rise to too large a tolerant response, leading to an inefficacy in adaptive immune function.

Implementation and Effects of Risk-Dependent Obstetric Care in the Netherlands (Expect Study II): Protocol for an Impact Study.

Science.gov (United States)

van Montfort, Pim; Willemse, Jessica Ppm; Dirksen, Carmen D; van Dooren, Ivo Ma; Meertens, Linda Je; Spaanderman, Marc Ea; Zelis, Maartje; Zwaan, Iris M; Scheepers, Hubertina Cj; Smits, Luc Jm

2018-05-04

Recently, validated risk models predicting adverse obstetric outcomes combined with risk-dependent care paths have been made available for early antenatal care in the southeastern part of the Netherlands. This study will evaluate implementation progress and impact of the new approach in obstetric care. The objective of this paper is to describe the design of a study evaluating the impact of implementing risk-dependent care. Validated first-trimester prediction models are embedded in daily clinical practice and combined with risk-dependent obstetric care paths. A multicenter prospective cohort study consisting of women who receive risk-dependent care is being performed from April 2017 to April 2018 (Expect Study II). Obstetric risk profiles will be calculated using a Web-based tool, the Expect prediction tool. The primary outcomes are the adherence of health care professionals and compliance of women. Secondary outcomes are patient satisfaction and cost-effectiveness. Outcome measures will be established using Web-based questionnaires. The secondary outcomes of the risk-dependent care cohort (Expect II) will be compared with the outcomes of a similar prospective cohort (Expect I). Women of this similar cohort received former care-as-usual and were prospectively included between July 1, 2013 and December 31, 2015 (Expect I). Currently, women are being recruited for the Expect Study II, and a total of 300 women are enrolled. This study will provide information about the implementation and impact of a new approach in obstetric care using prediction models and risk-dependent obstetric care paths. Netherlands Trial Register NTR4143; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=4143 (Archived by WebCite at http://www.webcitation.org/6t8ijtpd9). ©Pim van Montfort, Jessica PPM Willemse, Carmen D Dirksen, Ivo MA van Dooren, Linda JE Meertens, Marc EA Spaanderman, Maartje Zelis, Iris M Zwaan, Hubertina CJ Scheepers, Luc JM Smits. Originally published in JMIR

Progress of the volume FEL (VFEL) experiments in millimeter range

Science.gov (United States)

Baryshevsky, V. G.; Batrakov, K. G.; Gurinovich, A. A.; Ilienko, I. I.; Lobko, A. S.; Molchanov, P. V.; Moroz, V. I.; Sofronov, P. F.; Stolyarsky, V. I.

2003-07-01

Use of non-one-dimensional distributed feedback in Volume Free Electron Laser gives possibility of frequency tuning in wide range. In present work, dependence of lasing process on the angle between resonant diffraction grating grooves and direction of electron beam velocity is discussed.

The angular momentum dependence of complex fragment emission

International Nuclear Information System (INIS)

Sobtka, L.G.; Sarantites, D.G.; Li, Z.

1987-01-01

Large fragment (A > 4) production at high angular momentum is studied via the reaction, 200 MeV 45 Sc + 65 Cu. Comparisons of the fragment yields from this reaction (high angular momentum) to those from 93 Nb + Be (low angular momentum) are used to verify the strong angular momentum dependence of large fragment production predicted by equilibrium models. Details of the coincident γ-ray distributions not only confirm a rigidly rotating intermediate but also indicate that the widths of the primary L-wave distributions decrease with increasing symmetry in the decay channel. These data are used to test the asymmetry and L-wave dependence of emission barriers calculated from a rotating, finite range corrected, liquid drop model. 21 refs., 10 figs

Temperature dependence in magnetic particle imaging

Science.gov (United States)

Wells, James; Paysen, Hendrik; Kosch, Olaf; Trahms, Lutz; Wiekhorst, Frank

2018-05-01

Experimental results are presented demonstrating how temperature can influence the dynamics of magnetic nanoparticles (MNPs) in liquid suspension, when exposed to alternating magnetic fields in the kilohertz frequency range. The measurements used to probe the nanoparticle systems are directly linked to both the emerging biomedical technique of magnetic particle imaging (MPI), and to the recently proposed concept of remote nanoscale thermometry using MNPs under AC field excitation. Here, we report measurements on three common types of MNPs, two of which are currently leading candidates for use as tracers in MPI. Using highly-sensitive magnetic particle spectroscopy (MPS), we demonstrate significant and divergent thermal dependences in several key measures used in the evaluation of MNP dynamics for use in MPI and other applications. The temperature range studied was between 296 and 318 Kelvin, making our findings of particular importance for MPI and other biomedical technologies. Furthermore, we report the detection of the same temperature dependences in measurements conducted using the detection coils within an operational preclinical MPI scanner. This clearly shows the importance of considering temperature during MPI development, and the potential for temperature-resolved MPI using this system. We propose possible physical explanations for the differences in the behaviors observed between the different particle types, and discuss our results in terms of the opportunities and concerns they raise for MPI and other MNP based technologies.

Spin-dependent Nucleon Structure Studies at MIT/Bates

International Nuclear Information System (INIS)

Botto, T.

2005-01-01

We present preliminary results from recent measurements of the proton, neutron and deuterium electro-magnetic form factors obtained by the BLAST collaboration at the MIT/Bates Linear Accelerator Facility. BLAST (Bates Large Acceptance Spectrometer Toroid) is a large-acceptance multi-purpose detector dedicated to studies of exclusive spin-dependent electron scattering from internal polarized targets. BLAST makes use of stored electron beam currents in excess of 150 mA with a 60-70% polarization. The electron beam is let through a 15 mm diameter, 60 cm long open-ended storage cell which is fed with ultra-pure, high-polarization H1,D1 gas from an Atomic Beam Source. The target polarization can be rapidly reversed between different vector and tensor target states, thus minimizing systematic uncertainties. The target spin can be oriented to any in-plane direction via a set of Helmholtz coils. Target polarizations in the storage cell of up to 80% (vector) and 70% (tensor) have been routinely achieved over a period of several months. Our data on the D-vector(e-vector,e'n) reaction off vector polarized deuterium allow for a unique extraction of the neutron charge form factor G E n . At same time, complementary measurements of G M n , T20 and the spin-dependent nucleon momentum distributions in deuterium are obtained via the D-vector(e-vector,e'), D (e-vector,e'd) and D (e-vector,e'p) reactions. In addition, BLAST data on vector polarized hydrogen will provide novel measurements of the GE/GM form-factor ratio on the proton as well as of the spin-dependent electro-excitation of the Δ(1232) resonance. Such comprehensive program on few body physics is now well underway and preliminary data will be presented

Calculation of atom ranges in solids for quasi-small-angle scattering

International Nuclear Information System (INIS)

Pustovit, A.N.

2004-01-01

A formula for quasi-small-angle scattering of atomic particle and power law interaction potential have been used for the calculation of the differential cross-section, elastic stopping cross-section and a mean projected range in a solid. It is found that the limit energy transfer in the collisions depends on the screening of the power law interaction potentials. The calculated mean ranges in matter are compared with experimental data [ru

Dielectric Properties of Marsh Vegetation in a Frequency Range of 0.1-18 GHz Under Variation of Temperature and Moisture

Science.gov (United States)

Romanov, A. N.; Kochetkova, T. D.; Suslyaev, V. I.; Shcheglova, A. S.

2017-09-01

Dielectric characteristics of some species of marsh vegetation: lichen Cladonia stellaris (Opiz) Pouzar, moss Sphagnum, and a representative of Bryidae mosses - Dicranum polysetum are studied in the frequency range from 100 MHz to 18 GHz. At a frequency of 1.41 GHz, the influence of temperature in the range from -12 to +20°C on the behavior of dielectric characteristics of mosses, lichens, and peat is studied. The dependences of the dielectric characteristics of vegetation on the volumetric wetness are established.

[Benzodiazepine dependence and the risk of depression and anxiety disorders: seniors' health study].

Science.gov (United States)

Nkogho Mengue, P-G; Abdous, B; Berbiche, D; Preville, M; Voyer, P

2014-06-01

The objective of this study is to examine the relationship between benzodiazepine dependence and anxiety disorders and depression in people aged 65 years and over. We referred to the data from the study on the health of seniors, a survey of a representative sample of 707 benzodiazepine users living in the community in Quebec, Canada. Benzodiazepine dependence, anxiety disorders and depression were measured using self-reported questionnaires based on the criteria of the Diagnostic and Statistical Manual of Mental Disorders, fourth revised edition. Seniors have consumed an average daily dose of 6.1±7.6mg diazepam equivalent to an average of 205±130 days. The prevalence of benzodiazepine dependence has been estimated at 9.5%. This dependence increases the risk of minor depression for females (relative risk [RR]=4.36, confidence interval 95% [95% CI]=1.19 to 15.99). The results of this study suggest that the use of benzodiazepines is far from being optimal among seniors in Quebec. The proportion of seniors who develop an addiction is important. The results illustrate the need to develop and implement programs to improve the quality of benzodiazepine use among this population. Copyright © 2013 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

Study of heavy quarkonium with energy dependent potential

International Nuclear Information System (INIS)

Gupta, Pramila; Mehrotra, I

2009-01-01

It is well known that charmonium and bottonium states can be calculated by using a nonrelativistic Schrodinger equation. The basic reasons are: 1) the mass of charm and bottom quarks is much larger than QCD scale, which makes this system free of strong normalization effects and 2) the binding energy is small compared to the mass energy ψ and γ states in terms of nonrelativistic qq system governed by more or less phenomenological potentials. In the present work we have studied mass spectra of charmonium and bottonium using the following energy dependent model in the framework of nonrelativistic Schrodinger equation

Temperature dependence of ac response in diluted half-metallic CrO{sub 2} powder compact

Energy Technology Data Exchange (ETDEWEB)

Chen Yajie; Zhang Xiaoyu; Cai Tianyi; Li Zhenya

2004-10-06

We present a study on temperature dependence of impedance spectra of the cold-pressed chromium dioxide (CrO{sub 2})-titanic dioxide (TiO{sub 2}) composite over the temperature range of 77-300 K, and over the frequency range of 40 Hz-500 kHz. The microstructure of the sample is analyzed using transmission electron microscopy (TEM), SEM and X-ray diffraction (XRD). The impedance spectra exhibit a strong dependence upon temperature. By evaluating the ac electricity behavior of the composite, we find the experimental data are successfully described by a power-law behavior {sigma}{sub ac}=A(T){omega}{sup s}, in which the frequency exponent s shows slightly greater than a universal value (0{<=}s{<=}1), and rises approximately linearly with temperature over a broad range of low temperature.

Cell cycle phase dependent emergence of thymidylate synthase studied by monoclonal antibody (M-TS-4).

Science.gov (United States)

Shibui, S; Hoshino, T; Iwasaki, K; Nomura, K; Jastreboff, M M

1989-05-01

A method of identifying thymidylate synthase (TS) at the cellular level was developed using anti-TS monoclonal antibody (M-TS-4), a monoclonal antibody created against purified TS from a HeLa cell line. In HeLa cells and four human glioma cell lines (U-251, U-87, 343-MGA, and SF-188), TS was identified primarily in the cytoplasm. Autoradiographic and flow cytometric studies showed that TS appeared mainly in the G1 phase and subsided early in the S phase; thus, the G1 phase can be divided into TS-positive and -negative fractions. Nuclear TS was not demonstrated unequivocally with M-TS-4, and the relationship between nuclear TS and DNA synthesis could not be determined. Although the percentage of TS-positive cells was larger than the S-phase fraction measured by autoradiography after a pulse of tritiated thymidine or by the immunoperoxidase method using BUdR, the ratios were within a similar range (1.2-1.4) in all cell lines studied. Therefore, the S-phase fraction can be estimated indirectly from the percentage of TS-positive cells measured by M-TS-4. Because the emergence of TS detected by our method is cell cycle dependent, M-TS-4 may be useful for biochemical studies of TS and for cytokinetic analysis.

Magnetic losses of commercial REBCO coated conductors in the low frequency range

Science.gov (United States)

De Marzi, G.; Iannone, G.; Gambardella, U.

2018-05-01

We have investigated the frequency dependence of the magnetic losses of different 2 G commercial REBCO coated-conductor tapes in the low frequency range ∼1–10 mHz of applied magnetic field at 5 and 77 K. We explored high field range, well above the penetration field, with fields applied perpendicularly to the flat surface. We found that the in-field hysteresis losses increase with increasing frequencies in all the investigated high-temperature superconductor (HTS) tapes, following a power-law dependence. An electromagnetic 2D finite element method model, based on H-formulation, has also been implemented, in which the frequency dependence of the hysteretic loss is computed taking into account the measured power-law E(J) characteristic for the electric field, and the experimental J c(B). Experimental and numerical findings are in very good agreement, so an extrapolation to higher ramp rate values is possible, thus providing a useful basis for the assessment of the hysteresis losses in fusion and accelerator HTS magnets.

Circularly polarized microwaves for magnetic resonance study in the GHz range: Application to nitrogen-vacancy in diamonds

International Nuclear Information System (INIS)

Mrózek, M.; Rudnicki, D. S.; Gawlik, W.; Mlynarczyk, J.

2015-01-01

The ability to create time-dependent magnetic fields of controlled polarization is essential for many experiments with magnetic resonance. We describe a microstrip circuit that allows us to generate strong magnetic field at microwave frequencies with arbitrary adjusted polarization. The circuit performance is demonstrated by applying it to an optically detected magnetic resonance and Rabi nutation experiments in nitrogen-vacancy color centers in diamond. Thanks to high efficiency of the proposed microstrip circuit and degree of circular polarization of 85%; it is possible to address the specific spin states of a diamond sample using a low power microwave generator. The circuit may be applied to a wide range of magnetic resonance experiments with a well-controlled polarization of microwaves

Experimental study on stabilizing range extension of diamagnetic levitation under modulated magnetic field

Energy Technology Data Exchange (ETDEWEB)

Chow, T C S; Wong, P L; Liu, K P, E-mail: 50578230@student.cityu.edu.h, E-mail: meplwong@cityu.edu.h, E-mail: mekpliu@cityu.edu.h [Manufacturing Engineering and Engineering Management Department, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong)

2010-01-01

The real energy-free levitation exists with the help of diamagnetic material. Its ultra-high sensitivity to force is particularly attractive to micro/nano force sensing. A key parameter: Levitation Stabilizing Local Range, LR (allowable moving range of the floater) is critical to the load and self-rotating performance. Besides, larger LR reduces the energy loss due to the eddy current and has greater application potential. Recently, an idea of extending the LR by a modulating coil array has been validated using numerical simulation. This paper takes the next move to carry out an experimental study on the shape effect of stacked coil arrays with different currents on LR.

Metabolomic unveiling of a diverse range of green tea (Camellia sinensis) metabolites dependent on geography.

Science.gov (United States)

Lee, Jang-Eun; Lee, Bum-Jin; Chung, Jin-Oh; Kim, Hak-Nam; Kim, Eun-Hee; Jung, Sungheuk; Lee, Hyosang; Lee, Sang-Jun; Hong, Young-Shick

2015-05-01

Numerous factors such as geographical origin, cultivar, climate, cultural practices, and manufacturing processes influence the chemical compositions of tea, in the same way as growing conditions and grape variety affect wine quality. However, the relationships between these factors and tea chemical compositions are not well understood. In this study, a new approach for non-targeted or global analysis, i.e., metabolomics, which is highly reproducible and statistically effective in analysing a diverse range of compounds, was used to better understand the metabolome of Camellia sinensis and determine the influence of environmental factors, including geography, climate, and cultural practices, on tea-making. We found a strong correlation between environmental factors and the metabolome of green, white, and oolong teas from China, Japan, and South Korea. In particular, multivariate statistical analysis revealed strong inter-country and inter-city relationships in the levels of theanine and catechin derivatives found in green and white teas. This information might be useful for assessing tea quality or producing distinct tea products across different locations, and highlights simultaneous identification of diverse tea metabolites through an NMR-based metabolomics approach. Copyright © 2014 Elsevier Ltd. All rights reserved.

Temperature dependence of thermal expansion of cadmium sulfide in the temperature range 20 - 820 K

International Nuclear Information System (INIS)

Oskotskij, V.S.; Kobyakov, I.B.; Solodukhin, A.V.

1980-01-01

The linear thermal expansion of cadmium sulfide is measured perpendicularly (α 1 ) and parallelly (α 2 ) to the hexagonal axis in the temperature range from 20 to 820 K. Anisotropy is low at up to 80 K; rises at higher temperatures; at 3OO K α 1 /α 3 ratio is 1.8; at 820 K, 2.4. Heat expansion is negative at temperatures lower than 104.5 K(α 1 ) and 126.0 K(α 2 ). It achieves the minimum at 43.6 K (α 1 ) and 52.5K (α 3 ). The theory of heat expansion is plotted in the Debue, approximation and cadmium sulfide is considered as an isotope crystal with average elastic constants. Two parameters of the theory are determined by the position and value of the minimum of volumetric thermal expansion of the model isotope crystal. The theoretic curve agrees well with the experimental one at temperatures up to 160 K, i.e in the range of applicability of the Debue approximation and the isotropic model

Simulation studies of optimum energies for DXA: dependence on tissue type, patient size and dose model

International Nuclear Information System (INIS)

Michael, G. J.; Henderson, C. J.

1999-01-01

Dual-energy x-ray absorptiometry (DXA) is a well established technique for measuring bone mineral density (BMD). However, in recent years DXA is increasingly being used to measure body composition in terms of fat and fat-free mass. DXA scanners must also determine the soft tissue baseline value from soft-tissue-only regions adjacent to bone. The aim of this work is to determine, using computer simulations, the optimum x- ray energies for a number of dose models, different tissues, i.e. bone mineral, average soft tissue, lean soft tissue and fat; and a range of anatomical sites and patient sizes. Three models for patient dose were evaluated total beam energy, entrance exposure and absorbed dose calculated by Monte Carlo modelling. A range of tissue compositions and thicknesses were chosen to cover typical patient variations for the three sites femoral neck, PA spine and lateral spine. In this work, the optimisation of the energies is based on (1) the uncertainty that arises from the quantum statistical nature of the number of x-rays recorded by the detector, and (2) the radiation dose received by the patient. This study has deliberately not considered other parameters such as detector response, electronic noise, x-ray tube heat load etc, because these are technology dependent parameters, not ones that are inherent to the measuring technique. Optimisation of the energies is achieved by minimisation of the product of variance of density measurement and dose which is independent of the absolute intensities of the x-ray beams. The results obtained indicate that if solving for bone density, then E-low in the range 34 to 42 keV, E-high in the range 100 to 200 keV and incident intensity ratio (low energy/high energy) in the range 3 to 10 is a reasonable compromise for the normal range of patient sizes. The choice of energies is complicated by the fact that the DXA unit must also solve for fat and lean soft tissue in soft- tissue-only regions adjacent to the bone. In this

UMER: An analog computer for dynamics of swarms interacting via long-range forces

International Nuclear Information System (INIS)

Kishek, R.A.; Bai, G.; Bernal, S.; Feldman, D.; Godlove, T.F.; Haber, I.; O'Shea, P.G.; Quinn, B.; Papadopoulos, C.; Reiser, M.; Stratakis, D.; Tian, K.; Tobin, C.J.; Walter, M.

2006-01-01

Some of the most challenging and interesting problems in nature involve large numbers of objects or particles mutually interacting through long-range forces. Examples range from galaxies and plasmas to flocks of birds and traffic flow on a highway. Even in cases where the form of the interacting force is precisely known, such as the 1/r 2 -dependent Coulomb and gravitational forces, such problems present a formidable theoretical and modeling challenge for large numbers of interacting bodies. This paper reports on a newly constructed, scaled particle accelerator that will serve as an experimental testbed for the dynamics of swarms interacting through long-range forces. Primarily designed for intense beam dynamics studies for advanced accelerators, the University of Maryland Electron Ring (UMER) design is described in detail and an update on commissioning is provided. An example application to a system other than a charged particle beam is discussed

Energy-dependent inversion of p+16O scattering data

International Nuclear Information System (INIS)

Cooper, S.G.

1997-01-01

A fast iterative procedure is developed to determine potentials by inversion from elastic cross section, analysing powers and reaction cross-section measurements covering a wide energy range. The procedure incorporates both energy and parity dependence. The method is applied to extensive p+ 16 O scattering data for an energy range from 27.3 to 46.1 MeV, giving a solution which simultaneously reproduces the data at all energies. The wide angle data is well reproduced by including parity dependence and a linear energy dependence is established for the real potential, including the parity-dependent component. The real terms agree qualitatively with potentials derived from the single channel RGM, but the central and spin-orbit imaginary components have distinct features strongly suggestive of further non-local contributions, possibly arising from channel coupling. The large data set is found essential to reduce the potential ambiguities present when fitting scattering data. (orig.)

Time-dependent Fracture Behaviour of Polyampholyte Hydrogels

Science.gov (United States)

Sun, Tao Lin; Luo, Feng; Nakajima, Tasuku; Kurokawa, Takayuki; Gong, Jian Ping

Recently, we report that polyampholytes, polymers bearing randomly dispersed cationic and anionic repeat groups, form tough and self-healing hydrogels with excellent multiple mechanical functions. The randomness makes ionic bonds with a wide distribution of strength, via inter and intra chain complexation. As the breaking and reforming of ionic bonds are time dependent, the hydrogels exhibit rate dependent mechanical behaviour. We systematically studied the tearing energy by tearing test with various tearing velocity under different temperature, and the linear viscoelastic behaviour over a wide range of frequency and temperature. Results have shown that the tearing energy markedly increase with the crack velocity and decrease with the measured temperature. In accordance with the prediction of Williams, Landel, and Ferry (WLF) rate-temperature equivalence, a master curve of tearing energy dependence of crack velocity can be well constructed using the same shift factor from the linear viscoelastic data. The scaling relation of tearing energy as a function of crack velocity can be predicted well by the rheological data according to the developed linear fracture mechanics.

Neutron Scattering in Hydrogenous Moderators, Studied by Time Dependent Reaction Rate Method

Energy Technology Data Exchange (ETDEWEB)

Larsson, L G; Moeller, E; Purohit, S N

1966-03-15

The moderation and absorption of a neutron burst in water, poisoned with the non-1/v absorbers cadmium and gadolinium, has been followed on the time scale by multigroup calculations, using scattering kernels for the proton gas and the Nelkin model. The time dependent reaction rate curves for each absorber display clear differences for the two models, and the separation between the curves does not depend much on the absorber concentration. An experimental method for the measurement of infinite medium reaction rate curves in a limited geometry has been investigated. This method makes the measurement of the time dependent reaction rate generally useful for thermalization studies in a small geometry of a liquid hydrogenous moderator, provided that the experiment is coupled to programs for the calculation of scattering kernels and time dependent neutron spectra. Good agreement has been found between the reaction rate curve, measured with cadmium in water, and a calculated curve, where the Haywood kernel has been used.

Study of pseudo noise CW diode laser for ranging applications

Science.gov (United States)

Lee, Hyo S.; Ramaswami, Ravi

1992-01-01

A new Pseudo Random Noise (PN) modulated CW diode laser radar system is being developed for real time ranging of targets at both close and large distances (greater than 10 KM) to satisy a wide range of applications: from robotics to future space applications. Results from computer modeling and statistical analysis, along with some preliminary data obtained from a prototype system, are presented. The received signal is averaged for a short time to recover the target response function. It is found that even with uncooperative targets, based on the design parameters used (200-mW laser and 20-cm receiver), accurate ranging is possible up to about 15 KM, beyond which signal to noise ratio (SNR) becomes too small for real time analog detection.

Temperature dependence of microwave oscillations in magnetic tunnel junctions with a perpendicularly magnetized free layer

International Nuclear Information System (INIS)

Guo, Peng; Feng, Jiafeng; Wei, Hongxiang; Han, Xiufeng; Fang, Bin; Zhang, Baoshun; Zeng, Zhongming

2015-01-01

We experimentally study the temperature dependence of the spin-transfer-torque-induced microwave oscillations in MgO-based magnetic tunnel junction nanopillars with a perpendicularly magnetized free layer. We demonstrate that the oscillation frequency increases rapidly with decreasing temperature, which is mainly ascribed to the temperature dependence of both the saturation magnetization and the perpendicular magnetic anisotropy. We also find that a strong temperature dependence of the output power while a nonmonotonic temperature dependence of spectral linewidth are maintained for a constant dc bias in measured temperature range. Possible mechanisms leading to the different dependences of oscillation frequency, output power, and linewidth are discussed

Comparing of the Reaction Time in Substance-Dependent and Non-Dependent Individuals

Directory of Open Access Journals (Sweden)

Mohammad Narimani

2012-11-01

Full Text Available Aim: The aim of this study was to compare the simple, selective, and discrimination reaction time in substance-dependent and non-dependent individuals. Method: In this causal-comparative study, the population included of 425 males (opium and crystal dependents who were referred to addiction rehabilitation centers in Tabriz. By random sampling, 16 opium dependents, 16 crystal dependents, and 16 non-dependent individuals with no history of dependency as the compare group were selected. All groups peered in age, and marital status. For gathering data, “Addicts Admit Questionnaire” and laboratory device known as the "Reaction Time Assay" have been used. Results: The results of this study showed that there are significant differences among all groups in simple reaction time, choice reaction time and reaction time to auditory stimuli, but no significant difference in discrimination reaction time and reaction time to visual stimulus observed. Conclusion: The reaction time of substance-dependent groups is slower than non-dependent groups.

Ranging behavior relates to welfare indicators pre- and post-range access in commercial free-range broilers.

Science.gov (United States)

Taylor, Peta S; Hemsworth, Paul H; Groves, Peter J; Gebhardt-Henrich, Sabine G; Rault, Jean-Loup

2018-06-01

Little is known about the effect of accessing an outdoor range on chicken welfare. We tracked individual ranging behavior of 538 mixed-sex Ross 308 chickens on a commercial farm across 4 flocks in winter and summer. Before range access, at 17 to 19 d of age, and post-range access, at 30 to 33 and 42 to 46 d of age in winter and summer flocks respectively, welfare indicators were measured on chickens (pre-range: winter N = 292; summer N = 280; post-range: winter N = 131; summer N = 140), including weight, gait score, dermatitis and plumage condition. Post-ranging autopsies were performed (winter: N = 170; summer: N = 60) to assess breast burn, leg health, and ascites. Fewer chickens accessed the range in winter flocks (32.5%) than summer flocks (82.1%). Few relationships between welfare and ranging were identified in winter, likely due to minimal ranging and the earlier age of post-ranging data collection compared to summer flocks. In summer flocks prior to range access, chickens that accessed the range weighed 4.9% less (P = 0.03) than chickens that did not access the range. Pre-ranging weight, gait score, and overall plumage cover predicted the amount of range use by ranging chickens in summer flocks (P ranging behavior. In summer flocks post-range access, ranging chickens weighed 12.8% less than non-ranging chickens (P range visits were associated with lower weight (P range was associated with lower weight (P range in summer is partly related to changes in broiler chicken welfare. Further investigations are required to determine causation.

Quantifying species' range shifts in relation to climate change: a case study of Abies spp. in China.

Directory of Open Access Journals (Sweden)

Xiaojun Kou

Full Text Available Predicting species range shifts in response to climatic change is a central aspect of global change studies. An ever growing number of species have been modeled using a variety of species distribution models (SDMs. However, quantitative studies of the characteristics of range shifts are rare, predictions of range changes are hard to interpret, analyze and summarize, and comparisons between the various models are difficult to make when the number of species modeled is large. Maxent was used to model the distribution of 12 Abies spp. in China under current and possible future climate conditions. Two fuzzy set defined indices, range increment index (I and range overlapping index (O, were used to quantify range shifts of the chosen species. Correlation analyses were used to test the relationships between these indices and species distribution characteristics. Our results show that Abies spp. range increments (I were highly correlated with longitude, latitude, and mean roughness of their current distributions. Species overlapping (O was moderately, or not, correlated with these parameters. Neither range increments nor overlapping showed any correlation with species prevalence. These fuzzy sets defined indices provide ideal measures of species range shifts because they are stable and threshold-free. They are reliable indices that allow large numbers of species to be described, modeled, and compared on a variety of taxonomic levels.

Non-thermal influence of the mm-range electromagnetic radiation on the peroxide oxidation of egg yolk lipoproteins (in English)

Science.gov (United States)

Bulavin, L. A.; Zabolotna, N. M.

The effect of weak electromagnetic radiation in the millimetre range upon the chemiluminescence intensity accompanying the process of peroxide oxidization of lipoproteins was studied. It is shown that in the temperature range of 35div 43°C the intensity is independent of the temperature up to the experimental errors. It is though strongly dependent on the composition of the buffer solution and radiation frequency. The results are explained using a modified Onsager model.

Revealing the Cosmic Web-dependent Halo Bias

Science.gov (United States)

Yang, Xiaohu; Zhang, Youcai; Lu, Tianhuan; Wang, Huiyuan; Shi, Feng; Tweed, Dylan; Li, Shijie; Luo, Wentao; Lu, Yi; Yang, Lei

2017-10-01

Halo bias is the one of the key ingredients of the halo models. It was shown at a given redshift to be only dependent, to the first order, on the halo mass. In this study, four types of cosmic web environments—clusters, filaments, sheets, and voids—are defined within a state-of-the-art high-resolution N-body simulation. Within these environments, we use both halo-dark matter cross correlation and halo-halo autocorrelation functions to probe the clustering properties of halos. The nature of the halo bias differs strongly between the four different cosmic web environments described here. With respect to the overall population, halos in clusters have significantly lower biases in the {10}11.0˜ {10}13.5 {h}-1 {M}⊙ mass range. In other environments, however, halos show extremely enhanced biases up to a factor 10 in voids for halos of mass ˜ {10}12.0 {h}-1 {M}⊙ . Such a strong cosmic web environment dependence in the halo bias may play an important role in future cosmological and galaxy formation studies. Within this cosmic web framework, the age dependency of halo bias is found to be only significant in clusters and filaments for relatively small halos ≲ {10}12.5 {h}-1 {M}⊙ .

Demoralization in Opioid Dependent Patients: A Comparative Study with Cancer Patients and Community Subjects

NARCIS (Netherlands)

Jong, C.A.J. de; Kissane, D.W.; Geessink, R.J.; Velden, D. van der

2008-01-01

Aim: To study existential distress or demoralization expressed as meaninglessness and helplessness in opioid dependent patients. xxx Method: Comparison of existential distress between opioid dependent patients (n=131), patients with advanced cancer (n=100) and a community based sample without severe

[Study of defense styles, defenses and coping strategies in alcohol-dependent population].

Science.gov (United States)

Ribadier, A; Varescon, I

2017-05-01

Defense mechanisms have been seen to greatly change over time and across different definitions made by different theoretical currents. Recently with the definition provided by the DSM IV, defense mechanisms have integrated the concept of coping as a defensive factor. These mechanisms are no longer considered just through a psychodynamic approach but also through a cognitive and behavioral one. In recent years, new theories have therefore integrated these two components of the defensive operation. According to Chabrol and Callahan (2013), defense mechanisms precede coping strategies. In individuals with psychopathological disorders, these authors indicate a relative stability of these mechanisms. Also, we asked about the presence of unique characteristics among people with alcohol dependence. Indeed, studies conducted with people with alcohol dependence highlight the presence of a neurotic defense style and some highly immature defenses (projection, acting out, splitting and somatization). In terms of coping strategies, persons with alcohol dependence preferentially use avoidant strategies and strategies focused on emotion. However, although several studies have been conducted to assess coping strategies and defense styles within a population of individuals with an alcohol problem, at the present time none of them has taken into account all these aspects of defense mechanisms. The aim of this study is therefore to study the defenses and defense styles and coping strategies in an alcohol-dependent population. This multicenter study (3 CHU, 1 center of supportive care and prevention in addiction and 1 clinic) received a favorable opinion of an Institutional Review Board (IRB Registration #: 00001072). Eighty alcohol-dependent individuals responded to a questionnaire assessing sociodemographic characteristics and elements related to the course of consumption. Coping strategies were assessed by means of a questionnaire validated in French: the Brief Cope. The Defense

The host range of Phomopsis cirsii

DEFF Research Database (Denmark)

Leth, Vibeke; Andreasen, Christian

2012-01-01

echinus, Cirsiumvulgare and Cynaracardunculusvar.scolymus (artichoke) with symptoms such as restricted necrotic leaf spots and too early senescence or death of entire leaf. Eleven hosts for P. cirsii were recorded but despite the expanded range of hosts we expect that its host range will be within...... Cardueae.P.cirsii,poses multi-target potential against several annual and biennial weedy thistles from warmer climates. The pathogenicity of P. cirsii towards the artichoke, however, could limit its field of application especially in the Mediterranean area. The potential of P. cirsii as a control agent......, in areas where artichokes are cultivated, would depend on the existence of P.cirsii resistant varieties or the existence of P.cirsiiisolates non-pathogenic to artichoke....

Temperature-Dependent Dielectric Properties of Al/Epoxy Nanocomposites

Science.gov (United States)

Wang, Zijun; Zhou, Wenying; Sui, Xuezhen; Dong, Lina; Cai, Huiwu; Zuo, Jing; Chen, Qingguo

2016-06-01

Broadband dielectric spectroscopy was carried out to study the transition in electrical properties of Al/epoxy nanocomposites over the frequency range of 1-107 Hz and the temperature range of -20°C to 200°C. The dielectric permittivity, dissipation factor, and electrical conductivity of the nanocomposites increased with temperature and showed an abrupt increase around the glass transition temperature ( T g). The results clearly reveal an interesting transition of the electrical properties with increasing temperature: insulator below 70°C, conductor at about 70°C. The behavior of the transition in electrical properties of the nanocomposites was explored at different temperatures. The presence of relaxation peaks in the loss tangent and electric modulus spectra of the nanocomposites confirms that the chain segmental dynamics of the polymer is accompanied by the absorption of energy given to the system. It is suggested that the temperature-dependent transition of the electric properties in the nanocomposite is closely associated with the α-relaxation. The large increase in the dissipation factor and electric conductivity depends on the direct current conduction of thermally activated charge carriers resulting from the epoxy matrix above T g.

Experimental Searches for Exotic Short-Range Forces Using Mechanical Oscillators

Science.gov (United States)

Weisman, Evan

Experimental searches for forces beyond gravity and electromagnetism at short range have attracted a great deal of attention over the last decade. In this thesis I describe the test mass development for two new experiments searching for forces below 1 mm. Both modify a previous experiment that used 1 kHz mechanical oscillators as test masses with a stiff conducting shield between them to suppress backgrounds, a promising technique for probing exceptionally small distances at the limit of instrumental thermal noise. To further reduce thermal noise, one experiment will use plated silicon test masses at cryogenic temperatures. The other experiment, which searches for spin-dependent interactions, will apply the spin-polarizable material Dy3Fe5O 12 to the test mass surfaces. This material exhibits orbital compensation of the magnetism associated with its intrinsic electron spin, minimizing magnetic backgrounds. Several plated silicon test mass prototypes were fabricated using photolithography (useful in both experiments), and spin-dependent materials were synthesized with a simple chemical recipe. Both silicon and spin-dependent test masses demonstrate the mechanical and magnetic properties necessary for sensitive experiments. I also describe sensitivity calculations of another proposed spin-dependent experiment, based on a modified search for the electron electric dipole moment, which show unprecedented sensitivity to exotic monopole-dipole forces. Inspired by a finite element model, a study attempting to maximize detector quality factor versus geometry is also presented, with experimental results so far not explained by the model.

Study of TeV range cosmic ray detection with Cherenkov imaging techniques

International Nuclear Information System (INIS)

Ansari, R.; Gaillard, J.M.; Parrour, G.

1992-03-01

The Monte Carlo study of cosmic ray detection in the TeV energy range has been triggered by the authors' interest in the ARTEMIS (Antimatter Research Through the Earth Moon Ion Spectrometer) proposal. The properties of cosmic ray showers detected by Cherenkov imaging in the visible domain are studied. The detection sensitivity and the accuracy of the reconstruction of the parent particle direction using Cherenkov imaging are discussed. The backbone of the study is the atmospheric shower Monte Carlo generator developed by A.M. Hillas. A comparison between nucleon and photon induced showers of Cherenkov detection is also included. (R.P.) 14 refs., 48 figs., 3 tabs

Pulse Radiolysis Studies of Temperature Dependent Electron Transfers among Redox Centers in ba(3)-Cytochrome c Oxidase from Thermus thermophilus

DEFF Research Database (Denmark)

Farver, Ole; Wherland, Scot; Antholine, William E

2010-01-01

The functioning of cytochrome c oxidases involves orchestration of long-range electron transfer (ET) events among the four redox active metal centers. We report the temperature dependence of electron transfer from the Cu(A)(r) site to the low-spin heme-(a)b(o) site, i.e., Cu(A)(r) + heme-a(b)(o) ......The functioning of cytochrome c oxidases involves orchestration of long-range electron transfer (ET) events among the four redox active metal centers. We report the temperature dependence of electron transfer from the Cu(A)(r) site to the low-spin heme-(a)b(o) site, i.e., Cu(A)(r) + heme...... in cytochrome ba(3) had no effect on the rate of this reaction whereas the II-Met160Leu Cu(A)-mutation was slower by an amount corresponding to a decreased driving force of ∼0.06 eV. The structures support the presence of a common, electron-conducting "wire" between Cu(A) and heme-a(b). The transfer...

[Dependent patient and interpersonal dependency: psychotherapeutic strategies].