Sharp IV bounds on average treatment effects under endogeneity and noncompliance
Huber, Martin; Mellace, Giovanni
econometrics. Therefore, we use treatment monotonicity and/or stochastic dominance assumptions to derive sharp bounds on the average treatment effects of the treated population, the entire population, the compliers, the always takers, and the never takers. We also provide an application to labor market data...
Quasi-likelihood estimation of average treatment effects based on model information
Zhi-hua SUN
2007-01-01
In this paper, the estimation of average treatment effects is considered when we have the model information of the conditional mean and conditional variance for the responses given the covariates. The quasi-likelihood method adapted to treatment effects data is developed to estimate the parameters in the conditional mean and conditional variance models. Based on the model information, we define three estimators by imputation, regression and inverse probability weighted methods.All the estimators are shown asymptotically normal. Our simulation results show that by using the model information, the substantial efficiency gains are obtained which are comparable with the existing estimators.
Quasi-likelihood estimation of average treatment effects based on model information
2007-01-01
In this paper, the estimation of average treatment effects is considered when we have the model information of the conditional mean and conditional variance for the responses given the covariates. The quasi-likelihood method adapted to treatment effects data is developed to estimate the parameters in the conditional mean and conditional variance models. Based on the model information, we define three estimators by imputation, regression and inverse probability weighted methods. All the estimators are shown asymptotically normal. Our simulation results show that by using the model information, the substantial efficiency gains are obtained which are comparable with the existing estimators.
The Role of Gender in Agricultural Productivity in the Philippines: The Average Treatment Effect
Koirala, Krishna H.; MISHRA Ashok K.; Mohanty, Samarendu
2014-01-01
Using average treatment effect and data from 2012 the Central Luzon Loop Survey, this study investigates the role of gender in rice production. Results indicate that female-headed farm households, despite having limited access to land, have a higher value of rice production than their male counterparts. However, there is no significant difference between net farm incomes earned by male- and female-headed farm households. Female-headed households have higher fixed costs, consequently earning l...
Huber, Martin; Laffers, Lukas; Mellace, Giovanni
2016-01-01
subpopulations has been widely ignored in econometrics. We invoke treatment monotonicity and/or dominance assumptions to derive sharp bounds on the average treatment effects on the treated, as well as on other groups. Furthermore, we use our methods to assess the educational impact of a school voucher program in...
Balzer, Laura B; Petersen, Maya L; van der Laan, Mark J
2016-09-20
In cluster randomized trials, the study units usually are not a simple random sample from some clearly defined target population. Instead, the target population tends to be hypothetical or ill-defined, and the selection of study units tends to be systematic, driven by logistical and practical considerations. As a result, the population average treatment effect (PATE) may be neither well defined nor easily interpretable. In contrast, the sample average treatment effect (SATE) is the mean difference in the counterfactual outcomes for the study units. The sample parameter is easily interpretable and arguably the most relevant when the study units are not sampled from some specific super-population of interest. Furthermore, in most settings, the sample parameter will be estimated more efficiently than the population parameter. To the best of our knowledge, this is the first paper to propose using targeted maximum likelihood estimation (TMLE) for estimation and inference of the sample effect in trials with and without pair-matching. We study the asymptotic and finite sample properties of the TMLE for the sample effect and provide a conservative variance estimator. Finite sample simulations illustrate the potential gains in precision and power from selecting the sample effect as the target of inference. This work is motivated by the Sustainable East Africa Research in Community Health (SEARCH) study, a pair-matched, community randomized trial to estimate the effect of population-based HIV testing and streamlined ART on the 5-year cumulative HIV incidence (NCT01864603). The proposed methodology will be used in the primary analysis for the SEARCH trial. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27087478
The ionization chamber volume averaging effect is a well-known issue without an elegant solution. The purpose of this study is to propose a novel convolution-based approach to address the volume averaging effect in model-based treatment planning systems (TPSs). Ionization chamber-measured beam profiles can be regarded as the convolution between the detector response function and the implicit real profiles. Existing approaches address the issue by trying to remove the volume averaging effect from the measurement. In contrast, our proposed method imports the measured profiles directly into the TPS and addresses the problem by reoptimizing pertinent parameters of the TPS beam model. In the iterative beam modeling process, the TPS-calculated beam profiles are convolved with the same detector response function. Beam model parameters responsible for the penumbra are optimized to drive the convolved profiles to match the measured profiles. Since the convolved and the measured profiles are subject to identical volume averaging effect, the calculated profiles match the real profiles when the optimization converges. The method was applied to reoptimize a CC13 beam model commissioned with profiles measured with a standard ionization chamber (Scanditronix Wellhofer, Bartlett, TN). The reoptimized beam model was validated by comparing the TPS-calculated profiles with diode-measured profiles. Its performance in intensity-modulated radiation therapy (IMRT) quality assurance (QA) for ten head-and-neck patients was compared with the CC13 beam model and a clinical beam model (manually optimized, clinically proven) using standard Gamma comparisons. The beam profiles calculated with the reoptimized beam model showed excellent agreement with diode measurement at all measured geometries. Performance of the reoptimized beam model was comparable with that of the clinical beam model in IMRT QA. The average passing rates using the reoptimized beam model increased substantially from 92.1% to
Barraclough, Brendan; Li, Jonathan G.; Lebron, Sharon; Fan, Qiyong; Liu, Chihray; Yan, Guanghua
2015-08-01
The ionization chamber volume averaging effect is a well-known issue without an elegant solution. The purpose of this study is to propose a novel convolution-based approach to address the volume averaging effect in model-based treatment planning systems (TPSs). Ionization chamber-measured beam profiles can be regarded as the convolution between the detector response function and the implicit real profiles. Existing approaches address the issue by trying to remove the volume averaging effect from the measurement. In contrast, our proposed method imports the measured profiles directly into the TPS and addresses the problem by reoptimizing pertinent parameters of the TPS beam model. In the iterative beam modeling process, the TPS-calculated beam profiles are convolved with the same detector response function. Beam model parameters responsible for the penumbra are optimized to drive the convolved profiles to match the measured profiles. Since the convolved and the measured profiles are subject to identical volume averaging effect, the calculated profiles match the real profiles when the optimization converges. The method was applied to reoptimize a CC13 beam model commissioned with profiles measured with a standard ionization chamber (Scanditronix Wellhofer, Bartlett, TN). The reoptimized beam model was validated by comparing the TPS-calculated profiles with diode-measured profiles. Its performance in intensity-modulated radiation therapy (IMRT) quality assurance (QA) for ten head-and-neck patients was compared with the CC13 beam model and a clinical beam model (manually optimized, clinically proven) using standard Gamma comparisons. The beam profiles calculated with the reoptimized beam model showed excellent agreement with diode measurement at all measured geometries. Performance of the reoptimized beam model was comparable with that of the clinical beam model in IMRT QA. The average passing rates using the reoptimized beam model increased substantially from 92.1% to
Park, Soojin
2015-01-01
Identifying the causal mechanisms is becoming more essential in social and medical sciences. In the presence of treatment non-compliance, the Intent-To-Treated effect (hereafter, ITT effect) is identified as long as the treatment is randomized (Angrist et al., 1996). However, the mediated portion of effect is not identified without additional…
The balanced survivor average causal effect.
Greene, Tom; Joffe, Marshall; Hu, Bo; Li, Liang; Boucher, Ken
2013-01-01
Statistical analysis of longitudinal outcomes is often complicated by the absence of observable values in patients who die prior to their scheduled measurement. In such cases, the longitudinal data are said to be "truncated by death" to emphasize that the longitudinal measurements are not simply missing, but are undefined after death. Recently, the truncation by death problem has been investigated using the framework of principal stratification to define the target estimand as the survivor average causal effect (SACE), which in the context of a two-group randomized clinical trial is the mean difference in the longitudinal outcome between the treatment and control groups for the principal stratum of always-survivors. The SACE is not identified without untestable assumptions. These assumptions have often been formulated in terms of a monotonicity constraint requiring that the treatment does not reduce survival in any patient, in conjunction with assumed values for mean differences in the longitudinal outcome between certain principal strata. In this paper, we introduce an alternative estimand, the balanced-SACE, which is defined as the average causal effect on the longitudinal outcome in a particular subset of the always-survivors that is balanced with respect to the potential survival times under the treatment and control. We propose a simple estimator of the balanced-SACE that compares the longitudinal outcomes between equivalent fractions of the longest surviving patients between the treatment and control groups and does not require a monotonicity assumption. We provide expressions for the large sample bias of the estimator, along with sensitivity analyses and strategies to minimize this bias. We consider statistical inference under a bootstrap resampling procedure. PMID:23658214
Barraclough, B [J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL (United States); Li, J; Liu, C; Yan, G [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States)
2014-06-15
Purpose: Fourier-based deconvolution approaches used to eliminate ion chamber volume averaging effect (VAE) suffer from measurement noise. This work aims to investigate a novel method to account for ion chamber VAE through convolution in a commercial treatment planning system (TPS). Methods: Beam profiles of various field sizes and depths of an Elekta Synergy were collected with a finite size ion chamber (CC13) to derive a clinically acceptable beam model for a commercial TPS (Pinnacle{sup 3}), following the vendor-recommended modeling process. The TPS-calculated profiles were then externally convolved with a Gaussian function representing the chamber (σ = chamber radius). The agreement between the convolved profiles and measured profiles was evaluated with a one dimensional Gamma analysis (1%/1mm) as an objective function for optimization. TPS beam model parameters for focal and extra-focal sources were optimized and loaded back into the TPS for new calculation. This process was repeated until the objective function converged using a Simplex optimization method. Planar dose of 30 IMRT beams were calculated with both the clinical and the re-optimized beam models and compared with MapCHEC™ measurements to evaluate the new beam model. Results: After re-optimization, the two orthogonal source sizes for the focal source reduced from 0.20/0.16 cm to 0.01/0.01 cm, which were the minimal allowed values in Pinnacle. No significant change in the parameters for the extra-focal source was observed. With the re-optimized beam model, average Gamma passing rate for the 30 IMRT beams increased from 92.1% to 99.5% with a 3%/3mm criterion and from 82.6% to 97.2% with a 2%/2mm criterion. Conclusion: We proposed a novel method to account for ion chamber VAE in a commercial TPS through convolution. The reoptimized beam model, with VAE accounted for through a reliable and easy-to-implement convolution and optimization approach, outperforms the original beam model in standard IMRT QA
Purpose: Fourier-based deconvolution approaches used to eliminate ion chamber volume averaging effect (VAE) suffer from measurement noise. This work aims to investigate a novel method to account for ion chamber VAE through convolution in a commercial treatment planning system (TPS). Methods: Beam profiles of various field sizes and depths of an Elekta Synergy were collected with a finite size ion chamber (CC13) to derive a clinically acceptable beam model for a commercial TPS (Pinnacle3), following the vendor-recommended modeling process. The TPS-calculated profiles were then externally convolved with a Gaussian function representing the chamber (σ = chamber radius). The agreement between the convolved profiles and measured profiles was evaluated with a one dimensional Gamma analysis (1%/1mm) as an objective function for optimization. TPS beam model parameters for focal and extra-focal sources were optimized and loaded back into the TPS for new calculation. This process was repeated until the objective function converged using a Simplex optimization method. Planar dose of 30 IMRT beams were calculated with both the clinical and the re-optimized beam models and compared with MapCHEC™ measurements to evaluate the new beam model. Results: After re-optimization, the two orthogonal source sizes for the focal source reduced from 0.20/0.16 cm to 0.01/0.01 cm, which were the minimal allowed values in Pinnacle. No significant change in the parameters for the extra-focal source was observed. With the re-optimized beam model, average Gamma passing rate for the 30 IMRT beams increased from 92.1% to 99.5% with a 3%/3mm criterion and from 82.6% to 97.2% with a 2%/2mm criterion. Conclusion: We proposed a novel method to account for ion chamber VAE in a commercial TPS through convolution. The reoptimized beam model, with VAE accounted for through a reliable and easy-to-implement convolution and optimization approach, outperforms the original beam model in standard IMRT QA
Clarifying the Relationship between Average Excesses and Average Effects of Allele Substitutions.
Alvarez-Castro, José M; Yang, Rong-Cai
2012-01-01
Fisher's concepts of average effects and average excesses are at the core of the quantitative genetics theory. Their meaning and relationship have regularly been discussed and clarified. Here we develop a generalized set of one locus two-allele orthogonal contrasts for average excesses and average effects, based on the concept of the effective gene content of alleles. Our developments help understand the average excesses of alleles for the biallelic case. We dissect how average excesses relate to the average effects and to the decomposition of the genetic variance. PMID:22509178
Clarifying the relationship between average excesses and average effects of allele substitutions
Jose M eÁlvarez-Castro
2012-03-01
Full Text Available Fisher’s concepts of average effects and average excesses are at the core of the quantitative genetics theory. Their meaning and relationship have regularly been discussed and clarified. Here we develop a generalized set of one-locus two-allele orthogonal contrasts for average excesses and average effects, based on the concept of the effective gene content of alleles. Our developments help understand the average excesses of alleles for the biallelic case. We dissect how average excesses relate to the average effects and to the decomposition of the genetic variance.
Heckman, James J.; Lopes, Hedibert F.; Piatek, Rémi
2014-01-01
This paper contributes to the emerging Bayesian literature on treatment effects. It derives treatment parameters in the framework of a potential outcomes model with a treatment choice equation, where the correlation between the unobservable components of the model is driven by a low-dimensional v......This paper contributes to the emerging Bayesian literature on treatment effects. It derives treatment parameters in the framework of a potential outcomes model with a treatment choice equation, where the correlation between the unobservable components of the model is driven by a low...... observe the same person in both the treated and untreated states, but it also turns out to be straightforward to implement. Formulae are provided to compute mean treatment effects as well as their distributional versions. A Monte Carlo simulation study is carried out to illustrate how the methodology can...
Average and Quantile Effects in Nonseparable Panel Models
Chernozhukov, Victor; Hahn, Jinyong; Newey, Whitney
2011-01-01
This paper gives identification and estimation results for average and quantile effects in nonseparable panel models. Nonseparable models are important for modeling in a variety of economic settings, including discrete choice. We find that linear fixed effects estimators are not consistent for the average effect, due in part to that effect not being identified. Nonparametric bounds for quantile and average effects are derived for discrete regressors that are strictly exogenous or predetermined. We allow for location and scale time effects and show how monotonicity can be used to shrink the bounds. We derive rates at which the bounds tighten as the number $T$ of time series observations grows. We also consider semiparametric discrete choice models and find that the bounds for average effects tighten considerably. In numerical calculations we find that the bounds may be very tight for small numbers of observations, suggesting their use in practice. We propose two novel inference methods for parameters defined a...
Effects of spatial variability and scale on areal -average evapotranspiration
Famiglietti, J. S.; Wood, Eric F.
1993-01-01
This paper explores the effect of spatial variability and scale on areally-averaged evapotranspiration. A spatially-distributed water and energy balance model is employed to determine the effect of explicit patterns of model parameters and atmospheric forcing on modeled areally-averaged evapotranspiration over a range of increasing spatial scales. The analysis is performed from the local scale to the catchment scale. The study area is King's Creek catchment, an 11.7 sq km watershed located on the native tallgrass prairie of Kansas. The dominant controls on the scaling behavior of catchment-average evapotranspiration are investigated by simulation, as is the existence of a threshold scale for evapotranspiration modeling, with implications for explicit versus statistical representation of important process controls. It appears that some of our findings are fairly general, and will therefore provide a framework for understanding the scaling behavior of areally-averaged evapotranspiration at the catchment and larger scales.
Environmental stresses can alleviate the average deleterious effect of mutations
Leibler Stanislas
2003-05-01
Full Text Available Abstract Background Fundamental questions in evolutionary genetics, including the possible advantage of sexual reproduction, depend critically on the effects of deleterious mutations on fitness. Limited existing experimental evidence suggests that, on average, such effects tend to be aggravated under environmental stresses, consistent with the perception that stress diminishes the organism's ability to tolerate deleterious mutations. Here, we ask whether there are also stresses with the opposite influence, under which the organism becomes more tolerant to mutations. Results We developed a technique, based on bioluminescence, which allows accurate automated measurements of bacterial growth rates at very low cell densities. Using this system, we measured growth rates of Escherichia coli mutants under a diverse set of environmental stresses. In contrast to the perception that stress always reduces the organism's ability to tolerate mutations, our measurements identified stresses that do the opposite – that is, despite decreasing wild-type growth, they alleviate, on average, the effect of deleterious mutations. Conclusions Our results show a qualitative difference between various environmental stresses ranging from alleviation to aggravation of the average effect of mutations. We further show how the existence of stresses that are biased towards alleviation of the effects of mutations may imply the existence of average epistatic interactions between mutations. The results thus offer a connection between the two main factors controlling the effects of deleterious mutations: environmental conditions and epistatic interactions.
The effect of cosmic inhomogeneities on the average cosmological dynamics
Singh, T P
2011-01-01
It is generally assumed that on sufficiently large scales the Universe is well-described as a homogeneous, isotropic FRW cosmology with a dark energy. Does the formation of nonlinear cosmic inhomogeneities produce a significant effect on the average large-scale FLRW dynamics? As an answer, we suggest that if the length scale at which homogeneity sets in is much smaller than the Hubble length scale, the back-reaction due to averaging over inhomogeneities is negligible. This result is supported by more than one approach to study of averaging in cosmology. Even if no single approach is sufficiently rigorous and compelling, they are all in agreement that the effect of averaging in the real Universe is small. On the other hand, it is perhaps fair to say that there is no definitive observational evidence yet that there indeed is a homogeneity scale which is much smaller than the Hubble scale, or for that matter, if today's Universe is indeed homogeneous on large scales. If the Copernican principle can be observatio...
Thermal effects in high average power optical parametric amplifiers.
Rothhardt, Jan; Demmler, Stefan; Hädrich, Steffen; Peschel, Thomas; Limpert, Jens; Tünnermann, Andreas
2013-03-01
Optical parametric amplifiers (OPAs) have the reputation of being average power scalable due to the instantaneous nature of the parametric process (zero quantum defect). This Letter reveals serious challenges originating from thermal load in the nonlinear crystal caused by absorption. We investigate these thermal effects in high average power OPAs based on beta barium borate. Absorption of both pump and idler waves is identified to contribute significantly to heating of the nonlinear crystal. A temperature increase of up to 148 K with respect to the environment is observed and mechanical tensile stress up to 40 MPa is found, indicating a high risk of crystal fracture under such conditions. By restricting the idler to a wavelength range far from absorption bands and removing the crystal coating we reduce the peak temperature and the resulting temperature gradient significantly. Guidelines for further power scaling of OPAs and other nonlinear devices are given. PMID:23455291
Effect of random edge failure on the average path length
We study the effect of random removal of edges on the average path length (APL) in a large class of uncorrelated random networks in which vertices are characterized by hidden variables controlling the attachment of edges between pairs of vertices. A formula for approximating the APL of networks suffering random edge removal is derived first. Then, the formula is confirmed by simulations for classical ER (Erdoes and Renyi) random graphs, BA (Barabasi and Albert) networks, networks with exponential degree distributions as well as random networks with asymptotic power-law degree distributions with exponent α > 2. (paper)
On the physical effects of consistent cosmological averaging
Brown, Iain A; Herman, D Leigh; Latta, Joey
2013-01-01
We use cosmological perturbation theory to study the backreaction effects of a self-consistent and well-defined cosmological averaging on the dynamics and the evolution of the Universe. Working with a perturbed Friedman-Lemaitre-Robertson-Walker Einstein-de Sitter cosmological solution in a comoving volume-preserving gauge, we compute the expressions for the expansion scalar and deceleration parameter to second order, which we use to characterize the backreaction. We find that the fractional shift in the Hubble parameter with respect to the input background cosmological model is Delta~10^{-5}, which leads to an effective energy density of the order of a few times 10^{-5}. In addition, we find that an appropriate measure of the fractional shift in the deceleration parameter Q is very large.
Omura, Yoshiaki; Lu, Dominic; Jones, Marilyn K; Nihrane, Abdallah; Duvvi, Harsha; Yapor, Dario; Shimotsuura, Yasuhiro; Ohki, Motomu
2016-01-01
During the past 10 years, the author had found that the optimal dose of Vitamin D3 400 I.U. has safe & effective anticancer effects, while commonly used 2000-5000 I.U. of Vit. D3 often creates a 2-3 time increase in cancer markers. We examined the concentration of Taurine in normal internal organs and in cancer using Bi-Digital O-Ring Test. We found that Taurine levels in normal tissue are 4-6ng. But, the amount of Taurine of average normal value of 5.0-5.25ng was strikingly reduced to 0.0025-0.0028ng in this study of several examples in adenocarcinomas of the esophagus, stomach, pancreas, colon, prostate, and lung, as well as breast cancer. The lowest Taurine levels of 0.0002-0.0005ng were found in so called Zika virus infected babies from Brazil with microcephaly. While Vitamin D3 receptor stimulant 1α, 25 (OH)2D3 in normal tissues was 0.45-0.53ng, they were reduced to 0.025-0.006ng in cancers (1/100th-1/200th of normal value), particularly in various adenocarcinomas. All of these adenocarcinomas had about 1500ng HPV-16 viral infection. In 500 breast cancers, about 97% had HPV-16. The optimal dose of Taurine for average adult has been found to be about 175mg, rather than the widely used 500mg. In addition, since Taurine is markedly reduced to close to 1/1000th-1/2000th of its normal value in these cancer tissues, we examined the effect of the optimal dose of Taurine on cancer patients. Optimal dose of Taurine produced a very significant decrease in cancer-associated parameters, such as Oncogene C-fosAb2 & Integrin α5β1 being reduced to less than 1/1,000th, and 8-OH-dG (which increases in the presence of DNA mutation) reduced to less than 1/10th. The optimal dose of Taurine 175mg for average adult various cancer patient 3 times a day alone provide beneficial effects with very significant anti-cancer effects with strikingly increased urinary excretion of bacteria, viruses, & funguses, asbestos, toxic metals & other toxic substances. However, optimal doses of
Effects of polynomial trends on detrending moving average analysis
Shao, Ying-Hui; Jiang, Zhi-Qiang; Zhou, Wei-Xing
2015-01-01
The detrending moving average (DMA) algorithm is one of the best performing methods to quantify the long-term correlations in nonstationary time series. Many long-term correlated time series in real systems contain various trends. We investigate the effects of polynomial trends on the scaling behaviors and the performances of three widely used DMA methods including backward algorithm (BDMA), centered algorithm (CDMA) and forward algorithm (FDMA). We derive a general framework for polynomial trends and obtain analytical results for constant shifts and linear trends. We find that the behavior of the CDMA method is not influenced by constant shifts. In contrast, linear trends cause a crossover in the CDMA fluctuation functions. We also find that constant shifts and linear trends cause crossovers in the fluctuation functions obtained from the BDMA and FDMA methods. When a crossover exists, the scaling behavior at small scales comes from the intrinsic time series while that at large scales is dominated by the cons...
Analyzing Average and Conditional Effects with Multigroup Multilevel Structural EquationModels
Axel Mayer
2014-04-01
Full Text Available Conventionally, multilevel analysis of covariance (ML-ANCOVA has been therecommended approach for analyzing treatment effects in quasi-experimental multilevel designswith treatment application at the cluster-level. In this paper, we introduce the generalizedML-ANCOVA with linear effect functions that identifies average and conditional treatment effectsin the presence of treatment-covariate interactions. We show how the generalized ML-ANCOVAmodel can be estimated with multigroup multilevel structural equation models that offerconsiderable advances compared to traditional ML-ANCOVA. The proposed model takes intoaccount measurement error in the covariates, sampling error in contextual covariates,treatment-covariate interactions, and stochastic predictors. We illustrate the implementation ofML-ANCOVA with an example from educational effectiveness research where we estimateaverage and conditional effects of early transition to secondary schooling on readingcomprehension.
On the incentive effects of damage averaging in tort law
Tim Friehe
2007-01-01
It has been generally accepted for unilateral-care models that care incentives are not affected by the use of either accurate damages or average damages if injurers lack knowledge of the precise damage level they might cause. This paper shows that in bilateral-care models with heterogeneous victims, consequences of averages as damage measure are critically dependent on the weighing of respective harm levels. Importantly, we establish that there is an average measure which allows the attainmen...
Effective average action for gauge theories and exact evolution equations
We propose a new nonperturbative evolution equation for Yang-Mills theories. It describes the scale dependence of an effective action. The running of the nonabelian gauge coupling in arbitrary dimension is computed. (orig.)
Pulsar polarisation below 200 MHz: Average profiles and propagation effects
Noutsos, A; Kondratiev, V I; Weltevrede, P; Verbiest, J P W; Karastergiou, A; Kramer, M; Kuniyoshi, M; Alexov, A; Breton, R P; Bilous, A V; Cooper, S; Falcke, H; Grießmeier, J -M; Hassall, T E; Hessels, J W T; Keane, E F; Osłowski, S; Pilia, M; Serylak, M; Stappers, B W; ter Veen, S; van Leeuwen, J; Zagkouris, K; Anderson, K; Bähren, L; Bell, M; Broderick, J; Carbone, D; Cendes, Y; Coenen, T; Corbel, S; Eislöffel, J; Fender, R; Garsden, H; Jonker, P; Law, C; Marko, S; Masters, J; Miller-Jones, J; Molenaar, G; Osten, R; Pietka, M; Rol, E; Rowlinson, A; Scheers, B; Spreeuw, H; Staley, T; Stewart, A; Swinbank, J; Wijers, R; Wijnands, R; Wise, M; Zarka, P; van der Horst, A
2015-01-01
We present the highest-quality polarisation profiles to date of 16 non-recycled pulsars and four millisecond pulsars, observed below 200 MHz with the LOFAR high-band antennas. Based on the observed profiles, we perform an initial investigation of expected observational effects resulting from the propagation of polarised emission in the pulsar magnetosphere and the interstellar medium. The predictions of magnetospheric birefringence in pulsars have been tested using spectra of the pulse width and fractional polarisation from multifrequency data. The derived spectra offer only partial support for the expected effects of birefringence on the polarisation properties, with only about half of our sample being consistent with the model's predictions. It is noted that for some pulsars these measurements are contaminated by the effects of interstellar scattering. For a number of pulsars in our sample, we have observed significant variations in the amount of Faraday rotation as a function of pulse phase, which is possi...
Pulsar polarisation below 200 MHz: Average profiles and propagation effects
Noutsos, A.; Sobey, C.; Kondratiev, V. I.; Weltevrede, P.; Verbiest, J. P. W.; Karastergiou, A.; Kramer, M.; Kuniyoshi, M.; Alexov, A.; Breton, R. P.; Bilous, A. V.; Cooper, S.; Falcke, H.; Grießmeier, J.-M.; Hassall, T. E.; Hessels, J. W. T.; Keane, E. F.; Osłowski, S.; Pilia, M.; Serylak, M.; Stappers, B. W.; ter Veen, S.; van Leeuwen, J.; Zagkouris, K.; Anderson, K.; Bähren, L.; Bell, M.; Broderick, J.; Carbone, D.; Cendes, Y.; Coenen, T.; Corbel, S.; Eislöffel, J.; Fender, R.; Garsden, H.; Jonker, P.; Law, C.; Markoff, S.; Masters, J.; Miller-Jones, J.; Molenaar, G.; Osten, R.; Pietka, M.; Rol, E.; Rowlinson, A.; Scheers, B.; Spreeuw, H.; Staley, T.; Stewart, A.; Swinbank, J.; Wijers, R.; Wijnands, R.; Wise, M.; Zarka, P.; van der Horst, A.
2015-04-01
Aims: We present the highest-quality polarisation profiles to date of 16 non-recycled pulsars and four millisecond pulsars, observed below 200 MHz with the LOFAR high-band antennas. Based on the observed profiles, we perform an initial investigation of expected observational effects resulting from the propagation of polarised emission in the pulsar magnetosphere and the interstellar medium. Methods: The polarisation data presented in this paper have been calibrated for the geometric-projection and beam-shape effects that distort the polarised information as detected with the LOFAR antennas. We have used RM Synthesis to determine the amount of Faraday rotation in the data at the time of the observations. The ionospheric contribution to the measured Faraday rotation was estimated using a model of the ionosphere. To study the propagation effects, we have compared our low-frequency polarisation observations with archival data at 240, 400, 600, and 1400 MHz. Results: The predictions of magnetospheric birefringence in pulsars have been tested using spectra of the pulse width and fractional polarisation from multifrequency data. The derived spectra offer only partial support for the expected effects of birefringence on the polarisation properties, with only about half of our sample being consistent with the model's predictions. It is noted that for some pulsars these measurements are contaminated by the effects of interstellar scattering. For a number of pulsars in our sample, we have observed significant variations in the amount of Faraday rotation as a function of pulse phase, which is possibly an artefact of scattering. These variations are typically two orders of magnitude smaller than that observed at 1400 MHz by Noutsos et al. (2009), for a different sample of southern pulsars. In this paper we present a possible explanation for the difference in magnitude of this effect between the two frequencies, based on scattering. Finally, we have estimated the magnetospheric
Estimation of average causal effect using the restricted mean residual lifetime as effect measure
Mansourvar, Zahra; Martinussen, Torben
2016-01-01
Although mean residual lifetime is often of interest in biomedical studies, restricted mean residual lifetime must be considered in order to accommodate censoring. Differences in the restricted mean residual lifetime can be used as an appropriate quantity for comparing different treatment groups ...... is also applied to an observational data set of patients after an acute myocardial infarction event....... with respect to their survival times. In observational studies where the factor of interest is not randomized, covariate adjustment is needed to take into account imbalances in confounding factors. In this article, we develop an estimator for the average causal treatment difference using the restricted...
Thelma J. Mielenz
2015-10-01
Full Text Available Physical therapy researchers are interested in how beneficial an intervention is or the “treatment effect.” There are many measures of treatment effect that are applicable for understanding the efficacy and effectiveness of health interventions. Given that each treatment effect has its own set of advantages and disadvantages, understanding these characteristics can help guide which measure is most appropriate for a specific study. This article presents the more common treatment effects for both dichotomous and continues outcomes. The overall aim is to serve as a guide to newer physical therapy researchers on using and interpreting treatment effects.
Kristensen, Malene Lopez; Christensen, Palle Mark; Hallas, Jesper
2015-01-01
Objective To estimate the average postponement of death in statin trials. Setting A systematic literature review of all statin trials that presented all-cause survival curves for treated and untreated. Intervention Statin treatment compared to placebo. Primary outcome measures The average postponement of death as represented by the area between the survival curves. Results 6 studies for primary prevention and 5 for secondary prevention with a follow-up between 2.0 and 6.1 years were identifie...
27 CFR 19.763 - Record of average effective tax rates.
2010-04-01
...) Serial number of the batch record of each batch of the product which will be bottled or packaged, in... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Record of average... Records § 19.763 Record of average effective tax rates. (a) For each distilled spirits product to be...
The effects of average revenue regulation on electricity transmission investment and pricing
This paper investigates the long-run effects of average revenue regulation on an electricity transmission monopolist who applies a two-part tariff comprising a variable congestion price and a non-negative fixed access fee. A binding constraint on the monopolist's expected average revenue lowers the access fee, promotes transmission investment, and improves consumer surplus. In a case of any linear or log-linear electricity demand function with a positive probability that no congestion occurs, average revenue regulation is allocatively more efficient than a Coasian two-part tariff if the level of capacity under average revenue regulation is higher than that under a Coasian two-part tariff. (author)
A Conformal Fixed-Point Equation for the Effective Average Action
Rosten, Oliver J
2016-01-01
A Legendre transform of the recently discovered conformal fixed-point equation is constructed, providing an unintegrated equation encoding full conformal invariance within the framework of the effective average action.
Kristensen, Malene Lopez; Christensen, Palle Mark; Hallas, Jesper
2015-01-01
OBJECTIVE: To estimate the average postponement of death in statin trials. SETTING: A systematic literature review of all statin trials that presented all-cause survival curves for treated and untreated. INTERVENTION: Statin treatment compared to placebo. PRIMARY OUTCOME MEASURES: The average...... postponement of death as represented by the area between the survival curves. RESULTS: 6 studies for primary prevention and 5 for secondary prevention with a follow-up between 2.0 and 6.1 years were identified. Death was postponed between -5 and 19 days in primary prevention trials and between -10 and 27 days...... in secondary prevention trials. The median postponement of death for primary and secondary prevention trials were 3.2 and 4.1 days, respectively. CONCLUSIONS: Statin treatment results in a surprisingly small average gain in overall survival within the trials' running time. For patients whose life...
Thermal motion in proteins: Large effects on the time-averaged interaction energies
Goethe, Martin; Fita, Ignacio; Rubi, J. Miguel
2016-03-01
As a consequence of thermal motion, inter-atomic distances in proteins fluctuate strongly around their average values, and hence, also interaction energies (i.e. the pair-potentials evaluated at the fluctuating distances) are not constant in time but exhibit pronounced fluctuations. These fluctuations cause that time-averaged interaction energies do generally not coincide with the energy values obtained by evaluating the pair-potentials at the average distances. More precisely, time-averaged interaction energies behave typically smoother in terms of the average distance than the corresponding pair-potentials. This averaging effect is referred to as the thermal smoothing effect. Here, we estimate the strength of the thermal smoothing effect on the Lennard-Jones pair-potential for globular proteins at ambient conditions using x-ray diffraction and simulation data of a representative set of proteins. For specific atom species, we find a significant smoothing effect where the time-averaged interaction energy of a single atom pair can differ by various tens of cal/mol from the Lennard-Jones potential at the average distance. Importantly, we observe a dependency of the effect on the local environment of the involved atoms. The effect is typically weaker for bulky backbone atoms in beta sheets than for side-chain atoms belonging to other secondary structure on the surface of the protein. The results of this work have important practical implications for protein software relying on free energy expressions. We show that the accuracy of free energy expressions can largely be increased by introducing environment specific Lennard-Jones parameters accounting for the fact that the typical thermal motion of protein atoms depends strongly on their local environment.
The Better-than-Average Effect and 1 Corinthians 13: A Classroom Exercise
Swenson, John Eric, III; Schneller, Gregory R.; Henderson, Joy Ann
2014-01-01
People tend to evaluate themselves more favorably than they evaluate others, a tendency that is known as the better-than-average effect (BTA effect; Alicke, 1985; Brown, 1986). In an attempt to demonstrate the concept of the BTA effect, a classroom exercise was conducted with 78 undergraduate students in an "Introduction to Psychology"…
Diedrichs, Phillippa C; Lee, Christina
2010-06-01
Increasing body size and shape diversity in media imagery may promote positive body image. While research has largely focused on female models and women's body image, men may also be affected by unrealistic images. We examined the impact of average-size and muscular male fashion models on men's and women's body image and perceived advertisement effectiveness. A sample of 330 men and 289 women viewed one of four advertisement conditions: no models, muscular, average-slim or average-large models. Men and women rated average-size models as equally effective in advertisements as muscular models. For men, exposure to average-size models was associated with more positive body image in comparison to viewing no models, but no difference was found in comparison to muscular models. Similar results were found for women. Internalisation of beauty ideals did not moderate these effects. These findings suggest that average-size male models can promote positive body image and appeal to consumers. PMID:20488770
Effects of nuclear structure on average angular momentum in subbarrier fusion
Balantekin, A. B.; Bennett, J. R.; Kuyucak, S
1994-01-01
We investigate the effects of nuclear quadrupole and hexadecapole couplings on the average angular momentum in sub-barrier fusion reactions. This quantity could provide a probe for nuclear shapes, distinguishing between prolate vs. oblate quadrupole and positive vs. negative hexadecapole couplings. We describe the data in the O + Sm system and discuss heavier systems where shape effects become more pronounced.
LEVERAGE EFFECT FORECAST FOR THE YEAR 2014 THROUGH THE MOVING AVERAGE METHOD
HADA TEODOR
2015-03-01
Full Text Available It is very important for the proper development of various financial and economic activities to be an achievable goal. This can be determined by a forecast of a phenomenon in order to know where they could hover value. This paper is structured in three parts. The first part highlights the theoretical aspects of using the moving average method for determining the prognosis of a given phenomenon. The second part presents in detail the steps to follow within the moving average method. The phenomenon analyzed in this study is the leverage effect. We examine each step of the process, which will ultimately lead to a more precise forecast for the leverage effect. Each stage of the procedure is analyzed, which will lead in the end to a most accurate prognosis of the leverage effect. At the end of this paper, findings of practically using the moving average method, for establishing the forecast and its subsequent interpretations, will be presented.
Ra and the average effective strain of surface asperities deformed in metal-working processes
Bay, Niels; Wanheim, Tarras; Petersen, A. S
1975-01-01
Based upon a slip-line analysis of the plastic deformation of surface asperities, a theory is developed determining the Ra-value (c.l.a.) and the average effective strain in the surface layer when deforming asperities in metal-working processes. The ratio between Ra and Ra0, the Ra-value after and...... before deformation, is a function of the nominal normal pressure and the initial slope γ0 of the surface asperities. The last parameter does not influence Ra significantly. The average effective strain View the MathML sourcege in the deformed surface layer is a function of the nominal normal pressure and...
Numerical Investigation of Thermal Effect in Plasma Electrode Pockels Cell for High Average Power
CAO Ding-Xiang; ZHANG Xiong-Jun; ZHENG Wan-Guo; HE Shao-Bo; SUI Zhan
2006-01-01
@@ The average power of a Pockels cell is limited by thermal effects arising from the optical absorption of the laser pulse. These thermal effects can be managed by configuring the switch as a plasma-electrode thin plate Pockels cell, which works under heat-capacity operation. Simulation results show that, based on KD*P (in thickness 0.5cm) at an average power loading of 1 kW, the aperture integrated depolarization loss at 1.06 um is less than 10% in 5min working time.
The effects of noise in cardiac diffusion tensor imaging and the benefits of averaging complex data.
Scott, Andrew D; Nielles-Vallespin, Sonia; Ferreira, Pedro F; McGill, Laura-Ann; Pennell, Dudley J; Firmin, David N
2016-05-01
There is growing interest in cardiac diffusion tensor imaging (cDTI), but, unlike other diffusion MRI applications, there has been little investigation of the effects of noise on the parameters typically derived. One method of mitigating noise floor effects when there are multiple image averages, as in cDTI, is to average the complex rather than the magnitude data, but the phase contains contributions from bulk motion, which must be removed first. The effects of noise on the mean diffusivity (MD), fractional anisotropy (FA), helical angle (HA) and absolute secondary eigenvector angle (E2A) were simulated with various diffusion weightings (b values). The effect of averaging complex versus magnitude images was investigated. In vivo cDTI was performed in 10 healthy subjects with b = 500, 1000, 1500 and 2000 s/mm(2) . A technique for removing the motion-induced component of the image phase present in vivo was implemented by subtracting a low-resolution copy of the phase from the original images before averaging the complex images. MD, FA, E2A and the transmural gradient in HA were compared for un-averaged, magnitude- and complex-averaged reconstructions. Simulations demonstrated an over-estimation of FA and MD at low b values and an under-estimation at high b values. The transition is relatively signal-to-noise ratio (SNR) independent and occurs at a higher b value for FA (b = 1000-1250 s/mm(2) ) than MD (b ≈ 250 s/mm(2) ). E2A is under-estimated at low and high b values with a transition at b ≈ 1000 s/mm(2) , whereas the bias in HA is comparatively small. The under-estimation of FA and MD at high b values is caused by noise floor effects, which can be mitigated by averaging the complex data. Understanding the parameters of interest and the effects of noise informs the selection of the optimal b values. When complex data are available, they should be used to maximise the benefit from the acquisition of multiple averages. The combination of
Wicherts, Jelte M.; Dolan, Conor V.; Carlson, Jerry S.; van der Maas, Han L. J.
2010-01-01
This paper presents a systematic review of published data on the performance of sub-Saharan Africans on Raven's Progressive Matrices. The specific goals were to estimate the average level of performance, to study the Flynn Effect in African samples, and to examine the psychometric meaning of Raven's test scores as measures of general intelligence.…
LIU Yang; ZHANG Wei-min; CHEN Nai-lu; WANG Ming-hua; LI Lin-lin; Yuan Jian
2004-01-01
With the finite element analysis of viscous quenchant flow fields of the ASTM assembly, the effective average velocities of flow tubes are introduced in this paper. And through the results of experiments, the influences of quenchant velocities upon the whole cooling processes are discussed.
Chakraborty, Mousumi; Bawuah, Prince; Tan, Nicholas; Ervasti, Tuomas; Pääkkönen, Pertti; Zeitler, J. Axel; Ketolainen, Jarkko; Peiponen, Kai-Erik
2016-08-01
In this paper, we have studied terahertz (THz) pulse time delay of porous pharmaceutical microcrystalline compacts and also pharmaceutical tablets that contain indomethacin (painkiller) as an active pharmaceutical ingredient (API) and microcrystalline cellulose as the matrix of the tablet. The porosity of a pharmaceutical tablet is important because it affects the release of drug substance. In addition, surface roughness of the tablet has much importance regarding dissolution of the tablet and hence the rate of drug release. Here, we show, using a training set of tablets containing API and with a priori known tablet's quality parameters, that the effective refractive index (obtained from THz time delay data) of such porous tablets correlates with the average surface roughness of a tablet. Hence, THz pulse time delay measurement in the transmission mode provides information on both porosity and the average surface roughness of a compact. This is demonstrated for two different sets of pharmaceutical tablets having different porosity and average surface roughness values.
Attentional switching in intellectually gifted and average children: effects on performance and ERP.
Duan, Xiaoju; Shi, Jiannong
2014-04-01
The study compared the performance and brain activity of children who were intellectually gifted or of average intelligence. 13 intellectually gifted (4 girls, 9 boys; M age = 12.0 yr., SD = 0.2) and 13 average children (5 girls, 8 boys; M age = 11.9 yr., SD = 0.3) participated in a task-switching experiment. The children performed a task repeatedly (single-trial blocks) or switched between two different tasks (mixed-trial blocks). Intellectually gifted children performed quicker than the average group for both mixed and single-trial blocks. The electroencephalography P300 amplitude was larger in the mixed compared to the single-trial condition, but this effect was observed only in the gifted children. The results support the notion that gifted children are characterized by a faster maturation that leads to an 'adult-like' brain activity. PMID:24897910
Chakraborty, Mousumi; Bawuah, Prince; Tan, Nicholas; Ervasti, Tuomas; Pääkkönen, Pertti; Zeitler, J. Axel; Ketolainen, Jarkko; Peiponen, Kai-Erik
2016-03-01
In this paper, we have studied terahertz (THz) pulse time delay of porous pharmaceutical microcrystalline compacts and also pharmaceutical tablets that contain indomethacin (painkiller) as an active pharmaceutical ingredient (API) and microcrystalline cellulose as the matrix of the tablet. The porosity of a pharmaceutical tablet is important because it affects the release of drug substance. In addition, surface roughness of the tablet has much importance regarding dissolution of the tablet and hence the rate of drug release. Here, we show, using a training set of tablets containing API and with a priori known tablet's quality parameters, that the effective refractive index (obtained from THz time delay data) of such porous tablets correlates with the average surface roughness of a tablet. Hence, THz pulse time delay measurement in the transmission mode provides information on both porosity and the average surface roughness of a compact. This is demonstrated for two different sets of pharmaceutical tablets having different porosity and average surface roughness values.
The Effect of Area Averaging on the Approximated Profile of the H α Spectral Line
Bodnárová, M.; Utz, D.; Rybák, J.
2016-04-01
The Hα line is massively used as a diagnostics of the chromosphere. Often one needs to average the line profile over some area to increase the signal to noise ratio. Thus it is important to understand how derived parameters vary with changing approximations. In this study we investigate the effect of spatial averaging of a selected area on the temporal variations of the width, the intensity and the Dopplershift of the Hα spectral line profile. The approximated profile was deduced from co-temporal observations in five points throughout the Hα line profile obtained by the tunable Lyot filter installed on the Dutch Open Telescope. We found variations of the intensity and the Doppler velocities, which were independent of the size of the area used for the computation of the area averaged Hα spectral line profile.
Messamore, William G; Van Acker, Gustaf M; Hudson, Heather M; Zhang, Hongyu Y; Kovac, Anthony; Nazzaro, Jules; Cheney, Paul D
2016-07-01
While a large body of evidence supports the view that ipsilateral motor cortex may make an important contribution to normal movements and to recovery of function following cortical injury (Chollet et al. 1991; Fisher 1992; Caramia et al. 2000; Feydy et al. 2002), relatively little is known about the properties of output from motor cortex to ipsilateral muscles. Our aim in this study was to characterize the organization of output effects on hindlimb muscles from ipsilateral motor cortex using stimulus-triggered averaging of EMG activity. Stimulus-triggered averages of EMG activity were computed from microstimuli applied at 60-120 μA to sites in both contralateral and ipsilateral M1 of macaque monkeys during the performance of a hindlimb push-pull task. Although the poststimulus effects (PStEs) from ipsilateral M1 were fewer in number and substantially weaker, clear and consistent effects were obtained at an intensity of 120 μA. The mean onset latency of ipsilateral poststimulus facilitation was longer than contralateral effects by an average of 0.7 ms. However, the shortest latency effects in ipsilateral muscles were as short as the shortest latency effects in the corresponding contralateral muscles suggesting a minimal synaptic linkage that is equally direct in both cases. PMID:26088970
Scaling Effect of Area-Averaged NDVI: Monotonicity along the Spatial Resolution
Hiroki Yoshioka
2012-01-01
Full Text Available Changes in the spatial distributions of vegetation across the globe are routinely monitored by satellite remote sensing, in which the reflectance spectra over land surface areas are measured with spatial and temporal resolutions that depend on the satellite instrumentation. The use of multiple synchronized satellite sensors permits long-term monitoring with high spatial and temporal resolutions. However, differences in the spatial resolution of images collected by different sensors can introduce systematic biases, called scaling effects, into the biophysical retrievals. This study investigates the mechanism by which the scaling effects distort normalized difference vegetation index (NDVI. This study focused on the monotonicity of the area-averaged NDVI as a function of the spatial resolution. A monotonic relationship was proved analytically by using the resolution transform model proposed in this study in combination with a two-endmember linear mixture model. The monotonicity allowed the inherent uncertainties introduced by the scaling effects (error bounds to be explicitly determined by averaging the retrievals at the extrema of theresolutions. Error bounds could not be estimated, on the other hand, for non-monotonic relationships. Numerical simulations were conducted to demonstrate the monotonicity of the averaged NDVI along spatial resolution. This study provides a theoretical basis for the scaling effects and develops techniques for rectifying the scaling effects in biophysical retrievals to facilitate cross-sensor calibration for the long-term monitoring of vegetation dynamics.
Effects of network-average magnitude bias on yield estimates for underground nuclear explosions
The ISC body-wave magnitude, msub(b ISC), of presumed underground nuclear explosions in Kazakhstan, USSR, is shown to be systematically biased, by comparison to that recorded at the array station EKA (msub(b EKA)). This is found to be due in part to anelastic attenuation effects on msub(b EKA), but several characteristics of the ISC data demonstrate that the bias is also due to network-averaging effects. For the smaller explosions, those stations with a positive msub(b) bias dominate the data set, but the remainder of the network fails to detect the event. Conversely, for larger explosions, additional stations, with negative msub(b) bias will detect. Use of published station corrections for EKA allows estimation of an msub(b EKA): Y relationship and hence, a magnitude: yield relationship which takes account of network-average bias. (author)
We have investigated the effects of incorporating representations of heterogeneous chemical processes associated with stratospheric sulfuric acid aerosol into the LLNL two-dimensional, zonally averaged, model of the troposphere and stratosphere. Using distributions of aerosol surface area and volume density derived from SAGE 11 satellite observations, we were primarily interested in changes in partitioning within the Cl- and N- families in the lower stratosphere, compared to a model including only gas phase photochemical reactions
AMINIAN, Ensiyeh
2015-01-01
Abstract. Main aim of this research was investigating effect of carbohydrate solutions with different level of sager on average anaerobic power and fatigue index of karate players. Statistical sample of this research was 72 karate players of Khorasa Razavi province and 48 people were selected randomly. Average age, weight, height, and BMI were measures Average age of athletes was 22.23, average height 175cm and average weight 72.77. We used frequency distribution tables and indexes of the cen...
With the aim to investigate the justification of time-averaging of climate parameters in multicompartment modelling the effects of various climate parameters and different modes of entry on the predicted substances' total environmental burdens and the compartmental fractions were studied. A simple, non-steady state zero-dimensional (box) mass-balance model of intercompartmental mass exchange which comprises four compartments was used for this purpose. Each two runs were performed, one temporally unresolved (time-averaged conditions) and a time-resolved (hourly or higher) control run. In many cases significant discrepancies are predicted, depending on the substance and on the parameter. We find discrepancies exceeding 10% relative to the control run and up to an order of magnitude for prediction of the total environmental burden from neglecting seasonalities of the soil and ocean temperatures and the hydroxyl radical concentration in the atmosphere and diurnalities of atmospheric mixing depth and the hydroxyl radical concentration in the atmosphere. Under some conditions it was indicated that substance sensitivity could be explained by the magnitude of the sink terms in the compartment(s) with parameters varying. In general, however, any key for understanding substance sensitivity seems not be linked in an easy manner to the properties of the substance, to the fractions of its burden or to the sink terms in either of the compartments with parameters varying. Averaging of diurnal variability was found to cause errors of total environmental residence time of different sign for different substances. The effects of time-averaging of several parameters are in general not additive but synergistic as well as compensatory effects occur. An implication of these findings is that the ranking of substances according to persistence is sensitive to time resolution on the scale of hours to months. As a conclusion it is recommended to use high temporal resolution in multi
Guo, Xiaofeng; Yang, Ting; Sun, Yele
2015-08-01
Based on observations at the heights of 140 and 280 m on the Beijing 325-m meteorological tower, this study presents an assessment of the averaging period effects on eddy-covariance measurements of the momentum/scalar flux and transport efficiency during wintertime haze pollution. The study period, namely from January 6 to February 28 2013, is divided into different episodes of particulate pollution, as featured by varied amounts of the turbulent exchange and conditions of the atmospheric stability. Overall, turbulent fluxes of the momentum and scalars (heat, water vapor, and CO2) increase with the averaging period, namely from 5, 15, and 30 up to 60 min, an outcome most evident during the `transient' episodes (each lasting for 2-3 days, i.e., preceded and followed by clean-air days with mean concentrations of PM1 less than 40 μg m-3). The conventional choice of 30 min is deemed to be appropriate for calculating the momentum flux and its transport efficiency. By comparison, scalar fluxes and their transport efficiencies appear more sensitive to the choice of an averaging period, particularly at the upper level (i.e., 280 m). It is presupposed that, for urban environments, calculating the momentum and scalar fluxes could invoke separate averaging periods, rather than relying on a single prescription (e.g., 30 min). Furthermore, certain characteristics of urban turbulence are found less sensitive to the choice of an averaging period, such as the relationship between the heat-to-momentum transport efficiency and the local stability parameter.
Averaging Tesseral Effects: Closed Form Relegation versus Expansions of Elliptic Motion
Martin Lara
2013-01-01
Full Text Available Longitude-dependent terms of the geopotential cause nonnegligible short-period effects in orbit propagation of artificial satellites. Hence, accurate analytical and semianalytical theories must cope with tesseral harmonics. Modern algorithms for dealing analytically with them allow for closed form relegation. Nevertheless, current procedures for the relegation of tesseral effects from subsynchronous orbits are unavoidably related to orbit eccentricity, a key fact that is not enough emphasized and constrains application of this technique to small and moderate eccentricities. Comparisons with averaging procedures based on classical expansions of elliptic motion are carried out, and the pros and cons of each approach are discussed.
Radionuclides that are present in soil significantly affect terrestrial gamma radiation levels which in turn can be used for the assessment of terrestrial gamma dose rates. Natural radioactivity analysis has been done for the soil samples collected from different villages/towns of Hoshiarpur district of Punjab, India. The measurements have been carried out using HPGe detector based on high-resolution gamma spectrometry system. The calculated activity concentration values for terrestrial gamma viz. 238U, 232Th and 40K have been found to vary from 8.89 to 56.71 Bq kg-1, from 137.32 to 334.47 Bq kg-1 and from 823.62 to 1064.97 Bq kg-1, respectively. The total average absorbed dose rate in the study areas is 185.32 nGyh-1. The calculated value of average radium equivalent activity (401.13 Bq kg-1) exceeds the permissible limit (370 Bqkg-1) recommended by Organization for Economic Corporation and Development (OECD). The calculated average value of external hazard index (Hex) is 1.097. The calculated values of Indoor and Outdoor annual effective doses vary from 0.61 to 1.28 mSv and from 0.15 to 0.32 mSv, respectively. A positive correlation (R2 = 0.71) has also been observed for concentration of 232Th and 40K. (author)
Effects of measurement procedure and equipment on average room acoustic measurements
Gade, Anders Christian; Bradley, J S; Siebein, G W
1993-01-01
. In some of the halls measurements were repeated using the procedures of the other teams to make it possible to separate the effects of different equipment and different procedures. The paper will present position-averaged results from the three teams and will discuss reasons for the differences......This paper reports the results of a measurement tour of nine U.S. concert halls. Three measurements teams, from the University of Florida, the National Research Council of Canada, and the Technical University of Denmark, made parallel sets of measurements using their own equipment and procedures...
The effect of three-dimensional fields on bounce averaged particle drifts in a tokamak
The impact of applied 3D magnetic fields on the bounce-averaged precessional drifts in a tokamak plasma are calculated. Local 3D MHD equilibrium theory is used to construct solutions to the equilibrium equations in the vicinity of a magnetic surface for a large aspect ratio circular tokamak perturbed by applied 3D fields. Due to modulations of the local shear caused by near-resonant Pfirsch-Schlüter currents, relatively weak applied 3D fields can have a large effect on trapped particle precessional drifts
U.S. Department of Health & Human Services — A list of a variety of averages for each state or territory as well as the national average, including each quality measure, staffing, fine amount and number of...
Munoz-Menendez, Cristina; Conde-Leboran, Ivan; Baldomir, Daniel; Chubykalo-Fesenko, Oksana; Serantes, David
2015-11-01
An efficient and safe hyperthermia cancer treatment requires the accurate control of the heating performance of magnetic nanoparticles, which is directly related to their size. However, in any particle system the existence of some size polydispersity is experimentally unavoidable, which results in a different local heating output and consequently a different hyperthermia performance depending on the size of each particle. With the aim to shed some light on this significant issue, we have used a Monte Carlo technique to study the role of size polydispersity in heat dissipation at both the local (single particle) and global (macroscopic average) levels. We have systematically varied size polydispersity, temperature and interparticle dipolar interaction conditions, and evaluated local heating as a function of these parameters. Our results provide a simple guide on how to choose, for a given polydispersity degree, the more adequate average particle size so that the local variation in the released heat is kept within some limits that correspond to safety boundaries for the average-system hyperthermia performance. All together we believe that our results may help in the design of more effective magnetic hyperthermia applications. PMID:26437746
A note on scaling arguments in the effective average action formalism
Pagani, Carlo
2016-01-01
The effective average action (EAA) is a scale dependent effective action where a scale $k$ is introduced via an infrared regulator. The $k-$dependence of the EAA is governed by an exact flow equation to which one associates a boundary condition at a scale $\\mu$. We show that the $\\mu-$dependence of the EAA is controlled by an equation fully analogous to the Callan-Symanzik equation which allows to define scaling quantities straightforwardly. Particular attention is paid to composite operators which are introduced along with new sources. We discuss some simple solutions to the flow equation for composite operators and comment their implications in the case of a local potential approximation.
Nelson, C.; Mahoney, A.R.
1986-06-01
A significant drop in production efficiency has occurred over time at the Solar One facility at Barstow, California, primarily as a result of the degradation of the Pyromark Series 2500 black paint used as the absorptive coating on the receiver panels. As part of the investigation of the problem, the solar-averaged adsorptance properties of the paint were determined as a function of vitrification temperature, since it is known that a significant amount of the panel surface area at Solar One was vitrified at temperatures below those recommended by the paint manufacturer (540/sup 0/C, 1000/sup 0/F). Painted samples initially vitrified at 230/sup 0/C (450/sup 0/F), 315/sup 0/C (600/sup 0/F), 371/sup 0/C (700/sup 0/F), and 480/sup 0/C (900/sup 0/F) exhibited significantly lower solar-averaged absorptance values (0.02 absorptance units) compared to samples vitrified at 540/sup 0/C (1000/sup 0/F). Thus, Solar One began its service life below optimal levels. After 140 h of thermal aging at 370/sup 0/C (700/sup 0/F) and 540/sup 0/C (1000/sup 0/F), all samples regardless of their initial vitrification temperatures, attained the same solar-averaged absorptance value (..cap alpha../sub s/ = 0.973). Therefore, both the long-term low-temperature vitrification and the short-term high-temperature vitrification can be used to obtain optimal or near-optimal absorptance of solar flux. Futher thermal aging of vitrified samples did not result in paint degradation, clearly indicating that high solar flux is required to produce this phenomenon. The panels at Solar One never achieved optimal absorptance because their exposure to high solar flux negated the effect of long-term low-temperature vitrification during operation. On future central receiver projects, every effort should be made to properly vitrify the Pyromark coating before its exposure to high flux conditions.
Finite size effects in the averaged eigenvalue density of Wigner random-sign real symmetric matrices
Dhesi, G. S.; Ausloos, M.
2016-06-01
Nowadays, strict finite size effects must be taken into account in condensed matter problems when treated through models based on lattices or graphs. On the other hand, the cases of directed bonds or links are known to be highly relevant in topics ranging from ferroelectrics to quotation networks. Combining these two points leads us to examine finite size random matrices. To obtain basic materials properties, the Green's function associated with the matrix has to be calculated. To obtain the first finite size correction, a perturbative scheme is hereby developed within the framework of the replica method. The averaged eigenvalue spectrum and the corresponding Green's function of Wigner random sign real symmetric N ×N matrices to order 1 /N are finally obtained analytically. Related simulation results are also presented. The agreement is excellent between the analytical formulas and finite size matrix numerical diagonalization results, confirming the correctness of the first-order finite size expression.
The effect of temperature on the average volume of Barkhausen jump on Q235 carbon steel
Guo, Lei; Shu, Di; Yin, Liang; Chen, Juan; Qi, Xin
2016-06-01
On the basis of the average volume of Barkhausen jump (AVBJ) vbar generated by irreversible displacement of magnetic domain wall under the effect of the incentive magnetic field on ferromagnetic materials, the functional relationship between saturation magnetization Ms and temperature T is employed in this paper to deduce the explicit mathematical expression among AVBJ vbar, stress σ, incentive magnetic field H and temperature T. Then the change law between AVBJ vbar and temperature T is researched according to the mathematical expression. Moreover, the tensile and compressive stress experiments are carried out on Q235 carbon steel specimens at different temperature to verify our theories. This paper offers a series of theoretical bases to solve the temperature compensation problem of Barkhausen testing method.
Markley, F. Landis; Cheng, Yang; Crassidis, John L.; Oshman, Yaakov
2007-01-01
Many applications require an algorithm that averages quaternions in an optimal manner. For example, when combining the quaternion outputs of multiple star trackers having this output capability, it is desirable to properly average the quaternions without recomputing the attitude from the the raw star tracker data. Other applications requiring some sort of optimal quaternion averaging include particle filtering and multiple-model adaptive estimation, where weighted quaternions are used to determine the quaternion estimate. For spacecraft attitude estimation applications, derives an optimal averaging scheme to compute the average of a set of weighted attitude matrices using the singular value decomposition method. Focusing on a 4-dimensional quaternion Gaussian distribution on the unit hypersphere, provides an approach to computing the average quaternion by minimizing a quaternion cost function that is equivalent to the attitude matrix cost function Motivated by and extending its results, this Note derives an algorithm that deterniines an optimal average quaternion from a set of scalar- or matrix-weighted quaternions. Rirthermore, a sufficient condition for the uniqueness of the average quaternion, and the equivalence of the mininiization problem, stated herein, to maximum likelihood estimation, are shown.
Samya de Lara Lins de Araujo Pinheiro
2014-12-01
Full Text Available OBJECTIVE To analyze the effect of air pollution and temperature on mortality due to cardiovascular and respiratory diseases. METHODS We evaluated the isolated and synergistic effects of temperature and particulate matter with aerodynamic diameter 40 years old due to cardiovascular disease and that of individuals > 60 years old due to respiratory diseases in Sao Paulo, SP, Southeastern Brazil, between 1998 and 2008. Three methodologies were used to evaluate the isolated association: time-series analysis using Poisson regression model, bidirectional case-crossover analysis matched by period, and case-crossover analysis matched by the confounding factor, i.e., average temperature or pollutant concentration. The graphical representation of the response surface, generated by the interaction term between these factors added to the Poisson regression model, was interpreted to evaluate the synergistic effect of the risk factors. RESULTS No differences were observed between the results of the case-crossover and time-series analyses. The percentage change in the relative risk of cardiovascular and respiratory mortality was 0.85% (0.45;1.25 and 1.60% (0.74;2.46, respectively, due to an increase of 10 μg/m3 in the PM10 concentration. The pattern of correlation of the temperature with cardiovascular mortality was U-shaped and that with respiratory mortality was J-shaped, indicating an increased relative risk at high temperatures. The values for the interaction term indicated a higher relative risk for cardiovascular and respiratory mortalities at low temperatures and high temperatures, respectively, when the pollution levels reached approximately 60 μg/m3. CONCLUSIONS The positive association standardized in the Poisson regression model for pollutant concentration is not confounded by temperature, and the effect of temperature is not confounded by the pollutant levels in the time-series analysis. The simultaneous exposure to different levels of
Pinheiro, Samya de Lara Lins de Araujo; Saldiva, Paulo Hilário Nascimento; Schwartz, Joel; Zanobetti, Antonella
2014-12-01
OBJECTIVE To analyze the effect of air pollution and temperature on mortality due to cardiovascular and respiratory diseases. METHODS We evaluated the isolated and synergistic effects of temperature and particulate matter with aerodynamic diameter 40 years old due to cardiovascular disease and that of individuals > 60 years old due to respiratory diseases in Sao Paulo, SP, Southeastern Brazil, between 1998 and 2008. Three methodologies were used to evaluate the isolated association: time-series analysis using Poisson regression model, bidirectional case-crossover analysis matched by period, and case-crossover analysis matched by the confounding factor, i.e., average temperature or pollutant concentration. The graphical representation of the response surface, generated by the interaction term between these factors added to the Poisson regression model, was interpreted to evaluate the synergistic effect of the risk factors. RESULTS No differences were observed between the results of the case-crossover and time-series analyses. The percentage change in the relative risk of cardiovascular and respiratory mortality was 0.85% (0.45;1.25) and 1.60% (0.74;2.46), respectively, due to an increase of 10 μg/m3 in the PM10 concentration. The pattern of correlation of the temperature with cardiovascular mortality was U-shaped and that with respiratory mortality was J-shaped, indicating an increased relative risk at high temperatures. The values for the interaction term indicated a higher relative risk for cardiovascular and respiratory mortalities at low temperatures and high temperatures, respectively, when the pollution levels reached approximately 60 μg/m3. CONCLUSIONS The positive association standardized in the Poisson regression model for pollutant concentration is not confounded by temperature, and the effect of temperature is not confounded by the pollutant levels in the time-series analysis. The simultaneous exposure to different levels of environmental factors can
Effect of filter on average glandular dose and image quality in digital mammography
Songsaeng, C.; Krisanachinda, A.; Theerakul, K.
2016-03-01
To determine the average glandular dose and entrance surface air kerma in both phantoms and patients to assess image quality for different target-filters (W/Rh and W/Ag) in digital mammography system. The compressed breast thickness, compression force, average glandular dose, entrance surface air kerma, peak kilovoltage and tube current time were recorded and compared between W/Rh and W/Ag target filter. The CNR and the figure of merit were used to determine the effect of target filter on image quality. The mean AGD of the W/Rh target filter was 1.75 mGy, the mean ESAK was 6.67 mGy, the mean CBT was 54.1 mm, the mean CF was 14 1bs. The mean AGD of W/Ag target filter was 2.7 mGy, the mean ESAK was 12.6 mGy, the mean CBT was 75.5 mm, the mean CF was 15 1bs. In phantom study, the AGD was 1.2 mGy at 4 cm, 3.3 mGy at 6 cm and 3.83 mGy at 7 cm thickness. The FOM was 24.6, CNR was 9.02 at thickness 6 cm. The FOM was 18.4, CNR was 8.6 at thickness 7 cm. The AGD from Digital Mammogram system with W/Rh of thinner CBT was lower than the AGD from W/Ag target filter.
Effects of declining aerosols on projections of zonally averaged tropical precipitation
All of the representative concentration pathways (RCPs) assume that future emissions of aerosols and aerosol precursors will decline sharply. There is considerable evidence that historically increasing aerosols have substantially affected tropical precipitation, but the effects of projected aerosol declines have received little attention. We compare projections forced by the medium-low RCP4.5 pathway in two subsets of models from the Coupled Model Intercomparison Project Phase 5 (CMIP5): one group (HiForc) includes treatments of indirect aerosol effects on cloud albedo and cloud lifetime as well as direct aerosol effects, while the other group (LoForc) only treats direct aerosol effects. In this scenario we find that models in the HiForc group consistently project larger increases in both the mean and inter-hemispheric (north minus south) asymmetry of tropical sea-surface temperature (SST) and precipitation than do models in the LoForc group. Earlier projections from CMIP3, in which future aerosol declines were assumed to be smaller, behave more like the CMIP5 LoForc group. These results show that projected tropical SST and precipitation changes are sensitive to assumptions about aerosol emissions and indirect aerosol effects. If the real world resembles the HiForc group, then future aerosol changes are likely to be an important (even dominant) driver of tropical precipitation changes under low to moderate forcing scenarios. (letter)
Effect of Noise on the Average Received SNR of Different Combining Schemes
Shivani Gupta
2014-01-01
Full Text Available In wireless communication system, the multipath fading affects the performance of the system. Diversity-combining scheme is one of the powerful tools to mitigate the effect of fading. The multiple antennas provide an improvement in the capacity and reliability of the system. The performance of four combining schemes - Selection Combining (SC, Maximum Ratio Combining (MRC, Equal Gain Combining (EGC, and Generalised Selection combining (GSC- in the presence of both the perfect and an imperfect channel state information (CSI at the receiver is studied in this contribution by Monte Carlo simulations in the MATLAB environment, when communicating over Rayleigh fading channels. Our results show that the presence of the complex noise in the channel degrades the performance of the system in all four combining schemes, but the degradation in performance is found to be maximum in MRC and minimum in SC. Performance of EGC lies in between the performance of MRC and SC, whereas the performance of GSC depends upon the number of antennas being selected and it is upper bounded by the MRC and lower bounded by the SC. Also, the results show that as the value of SNR is increased the average received SNR increases in both the channels.
The effect of average A-site cation radius on TC in perovskite manganites
Three series of samples Ln0.7T0.3MnO3 (I), Ln0.7T0.3Mn0.9Cr0.1O3 (II), and Ln0.7T0.3Mn0.9Fe0.1O3 (III) (Ln=La, (La, Nd), (La, Y), T=Ca, CaSr, Sr) were prepared by sol-gel technique. The effect of the average A-site cation radius A> on the ferromagnetic transition temperature TC has been investigated. TC was obtained from M-T curves measured by vibrating sample magnetometer. For a little Nd3+ doped at the A-site, the TC of Ln0.7T0.3MnO3 (I) drops linearly with decreasing A> (1.18 AA>C values than series I due to the weakening of the influence of double-exchange interactions upon substituting Fe and Cr for Mn
Effect of spatial averaging on multifractal properties of meteorological time series
Hoffmann, Holger; Baranowski, Piotr; Krzyszczak, Jaromir; Zubik, Monika
2016-04-01
Introduction The process-based models for large-scale simulations require input of agro-meteorological quantities that are often in the form of time series of coarse spatial resolution. Therefore, the knowledge about their scaling properties is fundamental for transferring locally measured fluctuations to larger scales and vice-versa. However, the scaling analysis of these quantities is complicated due to the presence of localized trends and non-stationarities. Here we assess how spatially aggregating meteorological data to coarser resolutions affects the data's temporal scaling properties. While it is known that spatial aggregation may affect spatial data properties (Hoffmann et al., 2015), it is unknown how it affects temporal data properties. Therefore, the objective of this study was to characterize the aggregation effect (AE) with regard to both temporal and spatial input data properties considering scaling properties (i.e. statistical self-similarity) of the chosen agro-meteorological time series through multifractal detrended fluctuation analysis (MFDFA). Materials and Methods Time series coming from years 1982-2011 were spatially averaged from 1 to 10, 25, 50 and 100 km resolution to assess the impact of spatial aggregation. Daily minimum, mean and maximum air temperature (2 m), precipitation, global radiation, wind speed and relative humidity (Zhao et al., 2015) were used. To reveal the multifractal structure of the time series, we used the procedure described in Baranowski et al. (2015). The diversity of the studied multifractals was evaluated by the parameters of time series spectra. In order to analyse differences in multifractal properties to 1 km resolution grids, data of coarser resolutions was disaggregated to 1 km. Results and Conclusions Analysing the spatial averaging on multifractal properties we observed that spatial patterns of the multifractal spectrum (MS) of all meteorological variables differed from 1 km grids and MS-parameters were biased
Kim, Jonggun; Mohanty, Binayak P.; Shin, Yongchul
2015-08-01
Various hydrological models have been developed for estimating root zone soil moisture dynamics. These models, however, incorporated their own parameterization approaches indicating that the output from the different model inherent structures might include uncertainties because we do not know which model structure is correct for describing the real system. More recently, multimodel approaches using a Bayesian Model Averaging (BMA) scheme can improve the overall predictive skill while individual models retain their own uncertainties for simulated soil moisture based on a single set of weights in modeling under different land surface wetness conditions (e.g., wet, moderately wet, and dry conditions). In order to overcome their limitations, we developed a BMA-based multimodel simulation approach based on various soil wetness conditions for estimating effective surface soil moisture dynamics (0-5 cm) and quantifying uncertainties efficiently based on the land surface wetness conditions. The newly developed approach adapts three different hydrological models (i.e., Noah Land Surface Model, Noah LSM; Soil-Water-Atmosphere-Plant, SWAP; and Community Land Model, CLM) for simulating soil moisture. These models were integrated with a modified-microGA (advanced version of original Genetic Algorithm (GA)) to search for optimized soil parameters for each model. Soil moisture was simulated from the estimated soil parameters using the hydrological models in a forward mode. It was found that SWAP performed better than others during wet condition, while Noah LSM and CLM showed a good agreement with measurements during dry condition. Thus, we inferred that performance of individual models with different model structures can be different with land surface wetness. Taking into account the effects of soil wetness on different model performances, we categorized soil moisture measurements and estimated different weights for each category using the BMA scheme. Effective surface soil
George Chacko; Sanjiv Ranjan Das
1997-01-01
We develop analytic pricing models for options on averages by means of a state-space expansion method. These models augment the class of Asian options to markets where the underlying traded variable follows a mean-reverting process. The approach builds from the digital Asian option on the average and enables pricing of standard Asian calls and puts, caps and floors, as well as other exotica. The models may be used (i) to hedge long period interest rate risk cheaply, (ii) to hedge event risk (...
Pilar Díaz-Vázquez; Luis E. Arjona-Béjar
2013-01-01
This paper examines how labour turnover costs affect average labour demand when troughs are more persistent than booms. We show that the effect of firing costs on average labour demand is more expansionary (or less contractionary): the greater is the difference between the persistence of troughs and the persistence of booms, and the more prolonged are the macroeconomic shocks. This analysis may shed some light on the expected effect of a reduction of firing costs when an economy is suffering ...
Average-atom treatment of relaxation time in X-ray Thomson scattering from warm-dense matter
Johnson, Walter R.; Nilsen, Joseph
2015-01-01
The influence of finite relaxation times on Thomson scattering from warm-dense plasmas is examined within the framework of the average-atom approximation. Presently most calculations use the collision-free Lindhard dielectric function to evaluate the free-electron contribution to the Thomson cross section. In this work, we use the Mermin dielectric function, which includes relaxation time explicitly. The relaxation time is evaluated by treating the average atom as an impurity in a uniform ele...
Effect of various solvents on the viscosity-average molecular weight of poly (vinyl acetate)
Solution polymerization of Vinyl Acetate was carried out in various solvents (benzene, toluene, ethyl acetate, acetonitrile). Dilute solution viscometry was used to determine the viscosity-average molecular weight of the resulting Poly (Vinyl Acetate) (PV Ac) in each case. The viscosity-average molecular weight (M,J of PVAc was found to increase in the order benzene < toluene < ethyl acetate < acetonitrile, It was concluded that under the same reaction conditions (polymerization time, initiator quantity, solvent/monomer ratio, temperature), acetonitrile served as the best solvent for solution. polymerization of Vinyl Acetate monomer. (author)
Three types of polypropylenes commercially available for production of single use syringes were studied. All are intended (and used) for products sterilized by radiation. Average molecular weights were determined immediately after and at different times up to more than 2.5 years, after irradiation. (author)
Using National Data to Estimate Average Cost Effectiveness of EFNEP Outcomes by State/Territory
Baral, Ranju; Davis, George C.; Blake, Stephanie; You, Wen; Serrano, Elena
2013-01-01
This report demonstrates how existing national data can be used to first calculate upper limits on the average cost per participant and per outcome per state/territory for the Expanded Food and Nutrition Education Program (EFNEP). These upper limits can then be used by state EFNEP administrators to obtain more precise estimates for their states,…
Plantar Fasciitis: Prescribing Effective Treatments.
Shea, Michael; Fields, Karl B.
2002-01-01
Plantar fasciitis is an extremely common, painful injury seen among people in running and jumping sports. While prognosis for recovery with conservative care is excellent, prolonged duration of symptoms affects sports participation. Studies on treatment options show mixed results, so finding effective treatments can be challenging. A logical…
Average-atom treatment of relaxation time in X-ray Thomson scattering from warm-dense matter
Johnson, Walter R
2016-01-01
The influence of finite relaxation times on Thomson scattering from warm-dense plasmas is examined within the framework of the average-atom approximation. To this end, the Lindhard dielectric function, commonly used to evaluate the free-electron contribution to the Thomson cross section, is replaced by the Mermin dielectric function, which includes relaxation time explicitly. The relaxation time, which is evaluated by treating the average atom as an impurity in a uniform electron gas, depends critically on the transport cross section, which is evaluated in terms of scattering phase shifts in the average-atom potential. For the examples considered here, the calculated relaxation rates agree well, over a wide range of plasma densities and temperatures, with values inferred from the Ziman formula for the static conductivity and also with rates inferred from a fit to the frequency-dependent conductivity. Transport cross sections determined by the phase-shift analysis are compared with cross sections evaluated in ...
Roodposhti, Pezhman Mohamadi; Dabiri, Najafgholi
2012-01-01
Thirty two Holstein female calves (initial body weight = 40±3.0 kg) were used to investigate the effects of probiotic and prebiotic on average daily gain (ADG), fecal E. coli count, white blood cell count, plasma IgG1 level and cell-mediated immune response to injection of phytohemagglutinin in suckling female calves. Calves were assigned randomly to one of the four treatments, including whole milk without additives (control), whole milk containing probiotic, whole milk containing prebiotic a...
Average use of Alcohol and Binge Drinking in Pregnancy: Neuropsychological Effects at Age 5
Kilburn, Tina R.
Objectives The objective of this PhD. was to examine the relation between low weekly average maternal alcohol consumption and ‘Binge drinking' (defined as intake of 5 or more drinks per occasion) during pregnancy and information processing time (IPT) in children aged five years. Since a method...... that provided detailed information on maternal alcohol drinking patterns before and during pregnancy and other lifestyle factors. These women were categorized in groups of prenatally average alcohol intake and binge drinking, timing and number of episodes. At the age of five years the children of these women...... familiar to this age group. Two different versions, one with coloured fruits and one with black and white wild animals, were tried out. One version displayed rows of 1, 2 and 3 pictures and the other of 2, 3, and 4 pictures. For the development of the test 60 children, 39 girls and 21 boys, were selected...
Energy dependence of average transverse momentum in hadron production due to collective effects
Troshin, S M
2010-01-01
Motivated by the first measurements of the experiment CMS at the LHC at $\\sqrt{s}=0.9$ and 2.36 TeV, we discuss energy dependence of average transverse momentum of the secondary particles in hadron production in pp collisions. We suggest a possible explanation of this dependence as a result of collective rotation of the transient state and associate its further possible decrease with flattening off at higher energies with transition to the genuine QGP state of matter.
Saeedeh Ghafourian
2011-01-01
Full Text Available Single wall carbon nanotubes (SWCNT extensively are attractive from both theoretical and experimental point of view, due to its technological applications such as nano electronics devises. SWCNT are created by rolling a graphen sheet into a cyclindrical form. We have investigated the possibility of making a ferromagnetic semiconductor zigzag SWCNT by doping magnetic impurities. We found by increasing magnetic impurities doping on a zigzag SWCNT, average magnetization is increased and one can make a ferromagnetic semiconductor
van Osch, Y.M.J.; Blanken, Irene; Meijs, Maartje H. J.; van Wolferen, Job
2015-01-01
We tested whether the perceived physical attractiveness of a group is greater than the average attractiveness of its members. In nine studies, we find evidence for the so-called group attractiveness effect (GA-effect), using female, male, and mixed-gender groups, indicating that group impressions of
Antitumor effects of electrochemical treatment
Héctor Manuel Camué Ciria; Maraelys Morales González; Lisset Ortíz Zamora; Luis Enrique Bergues Cabrales; Gustavo Victoriano Sierra González; Luciana Oliveira de Oliveira; Rodrigo Zanella
2013-01-01
Electrochemical treatment is an alternative modality for tumor treatment based on the application of a low intensity direct electric current to the tumor tissue through two or more platinum electrodes placed within the tumor zone or in the surrounding areas.This treatment is noted for its great effectiveness,minimal invasiveness and local effect.Several studies have been conducted worldwide to evaluate the antitumoral effect of this therapy.In all these studies a variety of biochemical and physiological responses of tumors to the applied treatment have been obtained.By this reason,researchers have suggested various mechanisms to explain how direct electric current destroys tumor cells.Although,it is generally accepted this treatment induces electrolysis,electroosmosis and electroporation in tumoral tissues.However,action mechanism of this alternative modality on the tumor tissue is not well understood.Although the principle of Electrochemical treatment is simple,a standardized method is not yet available.The mechanism by which Electrochemical treatment affects tumor growth and survival may represent more complex process.The present work analyzes the latest and most important research done on the electrochemical treatment of tumors.We conclude with our point of view about the destruction mechanism features of this alternative therapy.Also,we suggest some mechanisms and strategies from the thermodynamic point of view for this therapy.In the area of Electrochemical treatment of cancer this tool has been exploited very little and much work remains to be done.Electrochemical treatment constitutes a good therapeutic option for patients that have failed the conventional oncology methods.
Effects of Lawsonia intracellularis on Average Daily Gain in finisher pigs
Johansen, M.; Nielsen, M.; Dahl, J.;
Lawsonia intracellularis (LI) is the causative agent of porcine proliferative enteropathy1, a disease that is found with high prevalence in all countries with industrial pig production. The infection is known to cause disease in different age groups. In pigs between 6 to 20 weeks of age the endem...... form called Porcine Intestinal Andenomatosis (PIA) is predominant. The clinical signs are diarrhoea, ill-thriftiness and wasting. The objective of this study was to estimate the impact of LI detected in faeces on Average Daily Gain (ADG) in grower-finisher pigs....
Estimation of treatment effects with high-dimensional controls
Belloni, Alexandre; Chernozhukov, Victor; Hansen, Christian
2011-01-01
We propose methods for inference on the average effect of a treatment on a scalar outcome in the presence of very many controls. Our setting is a partially linear regression model containing the treatment/policy variable and a large number p of controls or series terms, with p that is possibly much larger than the sample size n, but where only s
Li, Ye; Zhang, Yixin; Zhu, Yun; Chen, Minyu
2016-07-01
Based on the spatial power spectrum of the refractive index of anisotropic turbulence, the average polarizability of the Gaussian Schell-model quantized beams and lateral coherence length of the spherical wave propagating through the ocean water channel are derived. Numerical results show that, in strong temperature fluctuation, the depolarization effects of anisotropic turbulence are inferior to isotropic turbulence, as the other parameters of two links are the same. The depolarization effects of salinity fluctuation are less than the effects of the temperature fluctuation; the average polarizability of beams increases when increasing the inner scale of turbulence and the source's transverse size; and the larger rate of dissipation of kinetic energy per unit mass of fluid enhances the average polarizability of beams. The region of the receiving radius is smaller than the characteristic radius and the average polarizability of beams in isotropy turbulence is smaller than that of beams in anisotropy turbulence. However, the receiving radius region is larger than a characteristic radius and the average polarizability of beams in isotropy turbulence is larger than that of beams in anisotropy turbulence. PMID:27409215
TAKING INTO ACCOUNT THE EFFECT OF SECONDARY FLOWS IN DEPTH AVERAGED MORPHODYNAMIC SIMULATIONS
Andreas MALCHEREK
2001-01-01
Due to centrifugal forces in a bend secondary currents perpendicular to the main flow are generated.Because they can be the reason for important bed forming processes such as meandering they have to be taken into account in morphodynamic simulations. Their influence on the bed shear stress is proportional to the ratio of water depth and curve radius. The latter one is a curve parameter and is not defined in 2D digital terrain models. This paper presents a new formulation for the bed shear stress which takes into account the influence of secondary currents in depth averaged simulations without using the curve radius.The new formulation is applied to a morphodynamic model of the Weser estuary located in Northern Germany. Its capability to simulate the deflection of the bed shear stress in bends is shown.Because of the smoothness of the curves in the Weser no significant differences in the bed evolutioncan be seen in this case.
Averaging anisotropic cosmologies
We examine the effects of spatial inhomogeneities on irrotational anisotropic cosmologies by looking at the average properties of anisotropic pressure-free models. Adopting the Buchert scheme, we recast the averaged scalar equations in Bianchi-type form and close the standard system by introducing a propagation formula for the average shear magnitude. We then investigate the evolution of anisotropic average vacuum models and those filled with pressureless matter. In the latter case we show that the backreaction effects can modify the familiar Kasner-like singularity and potentially remove Mixmaster-type oscillations. The presence of nonzero average shear in our equations also allows us to examine the constraints that a phase of backreaction-driven accelerated expansion might put on the anisotropy of the averaged domain. We close by assessing the status of these and other attempts to define and calculate 'average' spacetime behaviour in general relativity
Differential effectiveness of placebo treatments
Meissner, Karin; Fässler, Margrit; Rücker, Gerta;
2013-01-01
IMPORTANCE When analyzing results of randomized clinical trials, the treatment with the greatest specific effect compared with its placebo control is considered to be the most effective one. Although systematic variations of improvements in placebo control groups would have important implications...... pooled random-effects estimates according to the type of placebo for the proportions of treatment response. We performed meta-regression analyses to identify sources of heterogeneity. In a network meta-analysis, direct and indirect comparisons within and across trials were combined. Additional analyses....... CONCLUSIONS AND RELEVANCE Sham acupuncture and sham surgery are associated with higher responder ratios than oral pharmacological placebos. Clinicians who treat patients with migraine should be aware that a relevant part of the overall effect they observe in practice might be due to nonspecific effects and...
van Osch, Yvette; Blanken, Irene; Meijs, Maartje H J; van Wolferen, Job
2015-04-01
We tested whether the perceived physical attractiveness of a group is greater than the average attractiveness of its members. In nine studies, we find evidence for the so-called group attractiveness effect (GA-effect), using female, male, and mixed-gender groups, indicating that group impressions of physical attractiveness are more positive than the average ratings of the group members. A meta-analysis on 33 comparisons reveals that the effect is medium to large (Cohen's d = 0.60) and moderated by group size. We explored two explanations for the GA-effect: (a) selective attention to attractive group members, and (b) the Gestalt principle of similarity. The results of our studies are in favor of the selective attention account: People selectively attend to the most attractive members of a group and their attractiveness has a greater influence on the evaluation of the group. PMID:25733515
Empirical insights into multi-grain averaging effects from ‘pseudo’ single-grain OSL measurements
In this study we assess the signatures of multi-grain averaging effects for a series of sedimentary samples taken from the archaeological site of Hotel California, Atapuerca, Spain. We focus on the special case of equivalent dose (De) measurements made on single-grain discs that contain more than one quartz grain in each of the individual grain-hole positions with the aims of (i) providing insight into the nature and extent of averaging effects in very small multi-grain aliquots of sedimentary quartz, and (ii) assessing the suitability of ‘pseudo’ single-grain De measurements for this particular dating application. Pseudo single-grain OSL measurements made on standard discs loaded with 90–100 μm grains (equivalent to ∼30 grains per hole) yield significantly different De distribution characteristics and finite mixture model (FMM) burial dose estimates compared with single-grain OSL measurements. Grains with aberrant luminescence behaviours, which are routinely rejected during single-grain analysis, exert strong averaging effects on the pseudo single-grain and multi-grain aliquot De distributions. Grain-hole averaging effects arising from pseudo single-grain measurements also give rise to ‘phantom’ dose components and are apt to provide bias assessments of quartz signal characteristics and grain type classifications. Though this is a site-specific study, it serves as a cautionary note for interpretations of other pseudo single-grain OSL and De datasets – particularly those obtained from measurements of discs containing several tens of grains per hole and those derived from complex depositional environments. The use of custom single-grain discs drilled with smaller sized grain holes is recommended as a means of limiting grain-hole averaging effects when dealing with very fine (<180 μm) sediments.
Samya de Lara Lins de Araujo Pinheiro; Paulo Hilário Nascimento Saldiva; Joel Schwartz; Antonella Zanobetti
2014-01-01
OBJECTIVE To analyze the effect of air pollution and temperature on mortality due to cardiovascular and respiratory diseases. METHODS We evaluated the isolated and synergistic effects of temperature and particulate matter with aerodynamic diameter 40 years old due to cardiovascular disease and that of individuals > 60 years old due to respiratory diseases in Sao Paulo, SP, Southeastern Brazil, between 1998 and 2008. Three methodologies were u...
The Good, the Bad, and the Average: Evidence on Ability Peer Effects in Schools
Victor Lavy; Olmo Silva; Felix Weinhardt
2012-01-01
We study ability peer effects in English secondary schools using data on four cohorts of students taking age-14 national tests and measuring peers' ability by prior achievements at age 11. Our identification is based on within-pupil regressions exploiting variation in achievements across three compulsory subjects tested at age 14 and age 11. Using this novel strategy, we find significant and sizable negative effects arising from bad peers at the bottom of the ability distribution but little e...
Averaging Tesseral Effects: Closed Form Relegation versus Expansions of Elliptic Motion
Martin Lara; San-Juan, Juan F.; Luis M. López-Ochoa
2013-01-01
Longitude-dependent terms of the geopotential cause nonnegligible short-period effects in orbit propagation of artificial satellites. Hence, accurate analytical and semianalytical theories must cope with tesseral harmonics. Modern algorithms for dealing analytically with them allow for closed form relegation. Nevertheless, current procedures for the relegation of tesseral effects from subsynchronous orbits are unavoidably related to orbit eccentricity, a key fact that is not enough emphasized...
Effect of nonuniform varying delay on the rate of convergence in averaging-based consensus
CİHAN, ONUR; AKAR, MEHMET
2015-01-01
This paper discusses the effect of nonuniform varying communication delay on distributed consensus algorithms in discrete time. After introducing the delayed mathematical model, we first investigate the ergodicity of the delayed system using the properties of scrambling matrices. Subsequently, the effect of nonuniform varying delay on convergence is examined. It is shown theoretically that nonuniform delay is not detrimental to the convergence rate of the algorithm for directed acyclic graphs...
Bernstein, R. B.
1973-01-01
The surprising feature of the Doppler problem in threshold determination is the 'amplification effect' of the target's thermal energy spread. The small thermal energy spread of the target molecules results in a large dispersion in relative kinetic energy. The Doppler broadening effect in connection with thermal energy beam experiments is discussed, and a procedure is recommended for the deconvolution of molecular scattering cross-section functions whose dominant dependence upon relative velocity is approximately that of the standard low-energy form.
Covariant and background independent functional RG flow for the effective average action
Safari, Mahmoud
2016-01-01
We extend our prescription for the construction of a covariant and background-independent effective action for scalar quantum field theories to the case where momentum modes below a certain scale are suppressed by the presence of an infrared regulator. The key step is an appropriate choice of the infrared cutoff for which the Ward identity, capturing the information from single-field dependence of the ultraviolet action, continues to be exactly solvable, and therefore, in addition to covariance, manifest background independence of the effective action is guaranteed at any scale. A practical consequence is that in this framework one can adopt truncations dependent on the single total field. Furthermore we discuss the necessary and sufficient conditions for the preservation of symmetries along the renormalization group flow.
The effect of capsule-filling machine vibrations on average fill weight.
Llusa, Marcos; Faulhammer, Eva; Biserni, Stefano; Calzolari, Vittorio; Lawrence, Simon; Bresciani, Massimo; Khinast, Johannes
2013-09-15
The aim of this paper is to study the effect of the speed of capsule filling and the inherent machine vibrations on fill weight for a dosator-nozzle machine. The results show that increasing speed of capsule filling amplifies the vibration intensity (as measured by Laser Doppler vibrometer) of the machine frame, which leads to powder densification. The mass of the powder (fill weight) collected via the nozzle is significantly larger at a higher capsule filling speed. Therefore, there is a correlation between powder densification under more intense vibrations and larger fill weights. Quality-by Design of powder based products should evaluate the effect of environmental vibrations on material attributes, which in turn may affect product quality. PMID:23872302
Marwan Mohammad Abu Orabi; Abdul Aziz F. AA. Saymeh
2012-01-01
Forecasting foreign exchange prices drives the concerns of financial investors and occupies the minds of financial analysts as well. Most Current forecasting formulas used to employ individual financial factors, either fundamental or technical. The purpose of this study is to test the effect of combined financial factors in forecasting future exchange prices of world currencies. This study used one fundamental factor and two technical factors merged in one mathematical formula. Researchers ha...
Location, investment and regional policy: the contribution of the average effective tax rate theory
Mignolet , Michel; Eyckmans, Nathalie; Meunier, Olivier
2004-01-01
For decades, most industrialised countries have implemented some forms of fiscal and financial incentives to stimulate fixed capital formation. Tax cuts and capital grants are of great use in regional policy. Since these instruments mobilise huge amounts of public resources the issue of their efficiency is of particular interest for policymakers. The impact of taxation on investment income was traditionally apprehended through models measuring the effective tax rate on marginal investments. H...
For AVLIS (Atomic Vapor Laser Isotope Separation), high average power frequency tunable laser is required to excite and ionize 235U. To realize such a tunable laser, a pump laser with high pulse repetition rate and high average power is inevitable. A copper vapor laser was thought to be a pump laser and had been developed. However, it is thought that all solid state Nd:YAG laser, pumped by laser diode array can reduce separation energy because of its high efficiency. And high average power Nd:YAG laser has been developing. In a laser crystal of such Nd:YAG laser, a part of pumping energy is converted to thermal energy, and thermal gradient is generated. As a result, thermal stress is caused and the effects of thermal lensing and depolarization of laser radiation are generated. These effects decrease output power and deteriorate laser beam quality. Therefore, analysis of thermal characteristics of laser crystal is carried out for laser crystals with the pulse repetition rate of around 2 kHz. As a result, a prospect of realizing high average power Nd:YAG is obtained. (author)
Effect of anode/filter combination on average glandular dose in mammography
Michal Biegala; Teresa Jakubowska; Karolina Markowska
2015-01-01
A comparative analysis of the mean glandular doses was conducted in 100 female patients who underwent screening mammography in 2011 and 2013. Siemens Mammomat Novation with the application of the W/Rh anode/filter combination was used in 2011, whereas in 2013 anode/filter combination was Mo/Mo or Mo/Rh. The functioning of mammography was checked and the effectiveness of the automatic exposure control (AEC) system was verified by measuring compensation of changes in the phantom thickness and m...
Assessing the effects of land-use changes on annual average gross erosion
Armando Brath
2002-01-01
Full Text Available The effects of land-use changes on potential annual gross erosion in the uplands of the Emilia-Romagna administrative region, a broad geographical area of some 22 000 km2 in northern-central Italy, have been analysed by application of the Universal Soil Loss Equation (USLE. The presence of an extended mountain chain, particularly subject to soil erosion, makes the estimation of annual gross erosion relevant in defining regional soil-conservation strategies. The USLE, derived empirically for plots, is usually applied at the basin scale. In the present study, the method is implemented in a distributed framework for the hilly and mountainous portion of Emilia-Romagna through a discretisation of the region into elementary square cells. The annual gross erosion is evaluated by combining morphological, pedological and climatic information. The stream network and the tributary area drained by each elementary cell, which are needed for the local application of the USLE, are derived automatically from a Digital Elevation Model (DEM of grid size 250 x 250 m. The rainfall erosivity factor is evaluated from local estimates of rainfall of six-hour storm duration and two-year return period. The soil erodibility and slope length-steepness factors are derived from digital maps of land use, pedology and geomorphology. Furthermore, historical land-use maps of the district of Bologna (a large portion — 3720 km2 — of the area under study, allow the effect of actual land use changes on the soil erosion process to be assessed. The analysis shows the influence of land-use changes on annual gross erosion as well as the increasing vulnerability of upland areas to soil erosion processes during recent decades. Keywords: USLE, gross erosion, distributed modelling, land use changes, northern-central Italy
Fernández, B.; García-Dorado, A; Caballero, A.
2005-01-01
We investigate the impact of antagonistic pleiotropy on the most widely used methods of estimation of the average coefficient of dominance of deleterious mutations from segregating populations. A proportion of the deleterious mutations affecting a given studied fitness component are assumed to have an advantageous effect on another one, generating overdominance on global fitness. Using diffusion approximations and transition matrix methods, we obtain the distribution of gene frequencies for n...
Fernández, B; García-Dorado, A; Caballero, A
2005-12-01
We investigate the impact of antagonistic pleiotropy on the most widely used methods of estimation of the average coefficient of dominance of deleterious mutations from segregating populations. A proportion of the deleterious mutations affecting a given studied fitness component are assumed to have an advantageous effect on another one, generating overdominance on global fitness. Using diffusion approximations and transition matrix methods, we obtain the distribution of gene frequencies for nonpleiotropic and pleiotropic mutations in populations at the mutation-selection-drift balance. From these distributions we build homozygous and heterozygous chromosomes and assess the behavior of the estimators of dominance. A very small number of deleterious mutations with antagonistic pleiotropy produces substantial increases on the estimate of the average degree of dominance of mutations affecting the fitness component under study. For example, estimates are increased three- to fivefold when 2% of segregating loci are over-dominant for fitness. In contrast, strengthening pleiotropy, where pleiotropic effects are assumed to be also deleterious, has little effect on the estimates of the average degree of dominance, supporting previous results. The antagonistic pleiotropy model considered, applied under mutational parameters described in the literature, produces patterns for the distribution of chromosomal viabilities, levels of genetic variance, and homozygous mutation load generally consistent with those observed empirically for viability in Drosophila melanogaster. PMID:16118193
Hulman, Sonia; Musci, Michael; Stang, Ellen
2015-01-01
Abstract Prescription opioid and heroin abuse have been increasing steadily year after year, and continue to be a serious national problem. A sequela of the increase in opioid abuse has been an increase in the number of infants born with opioid dependence. These infants often require costly, prolonged stays in the neonatal intensive care unit (NICU) for drug withdrawal treatment. The authors studied a population of infants from a large Medicaid health plan who were born with neonatal abstinence syndrome (NAS) secondary to in utero opioid exposure to assess the average length of stay in the NICU, and to determine the variables that may account for differences in interinstitutional lengths of stay. The overall average length of stay for NAS was 21.1 days for the 139 infants included in the study. Analysis of the medication used for treatment revealed that infants who were treated with a combined inpatient/outpatient regimen with methadone had an average length of stay of 11.4 days versus 25.1 days for infants who were treated entirely as inpatients (PPopulation Health Management 2015;18:392–397) PMID:25803316
Vranckx, Stijn; Vos, Peter; Maiheu, Bino; Janssen, Stijn
2015-11-01
Effects of vegetation on pollutant dispersion receive increased attention in attempts to reduce air pollutant concentration levels in the urban environment. In this study, we examine the influence of vegetation on the concentrations of traffic pollutants in urban street canyons using numerical simulations with the CFD code OpenFOAM. This CFD approach is validated against literature wind tunnel data of traffic pollutant dispersion in street canyons. The impact of trees is simulated for a variety of vegetation types and the full range of approaching wind directions at 15° interval. All these results are combined using meteo statistics, including effects of seasonal leaf loss, to determine the annual average effect of trees in street canyons. This analysis is performed for two pollutants, elemental carbon (EC) and PM10, using background concentrations and emission strengths for the city of Antwerp, Belgium. The results show that due to the presence of trees the annual average pollutant concentrations increase with about 8% (range of 1% to 13%) for EC and with about 1.4% (range of 0.2 to 2.6%) for PM10. The study indicates that this annual effect is considerably smaller than earlier estimates which are generally based on a specific set of governing conditions (1 wind direction, full leafed trees and peak hour traffic emissions). PMID:26100726
Huber, Martin
2012-01-01
As any empirical method used for causal analysis, social experiments are prone to attrition which may flaw the validity of the results. This article considers the problem of partially missing outcomes in experiments. First, it systematically reveals under which forms of attrition--in terms of its relation to observable and/or unobservable…
Huber, Martin
2012-01-01
As any empirical method used for causal analysis, social experiments are prone to attrition which may flaw the validity of the results. This paper considers the problem of partially missing outcomes in experiments. Firstly, it systematically reveals under which forms of attrition - in terms of its relation to observable and/or unobservable factors - experiments do (not) yield causal parameters. Secondly, it shows how the various forms of attrition can be controlled for by different methods of...
Identification of average treatment effects in social experiments under different forms of attrition
Martin Huber
2010-01-01
As any empirical method used for causal analysis, social experiments are prone to attrition which may flaw the validity of the results. This paper considers the problem of partially missing outcomes in experiments. Firstly, it systematically reveals under which forms of attrition - in terms of its relation to observable and/or unobservable factors - experiments do (not) yield causal parameters. Secondly, it shows how the various forms of attrition can be controlled for by different methods of...
Baijie Yang
2013-03-01
Full Text Available Because the average students are the prevailing part of the student population, it is important but difficult for the educators to help average students by improving their learning efficiency and learning outcome in school tests. We conducted a quasi-experiment with two English classes taught by one teacher in the second term of the first year of a junior high school. The experimental class was composed of average students (N=37, while the control class comprised talented students (N=34. Therefore the two classes performed differently in English subject with mean difference of 13.48 that is statistically significant based on the independent sample T-Test analysis. We tailored the web-based intelligent English instruction system, called Computer Simulation in Educational Communication (CSIEC and featured with instant feedback, to the learning content in the experiment term, and the experimental class used it one school hour per week throughout the term. This blended learning setting with the focus on vocabulary and dialogue acquisition helped the students in the experimental class improve their learning performance gradually. The mean difference of the final test between the two classes was decreased to 3.78, while the mean difference of the test designed for the specially drilled vocabulary knowledge was decreased to 2.38 and was statistically not significant. The student interview and survey also demonstrated the students’ favor to the blended learning system. We conclude that the long-term integration of this content oriented blended learning system featured with instant feedback into ordinary class is an effective approach to assist the average students to catch up with the talented ones.
Bruch, Sarah; Grigg, Jeffrey; Hanselman, Paul
2010-01-01
This study focuses on how the treatment effects of a teacher professional development initiative in science differed by school capacity. In other words, the authors are primarily concerned with treatment effect heterogeneity. As such, this paper complements ongoing evaluation of the average treatment effects of the initiative over time. The…
Bassetti, Bruno; Zarei, Mina; Cosentino Lagomarsino, Marco; Bianconi, Ginestra
2009-12-01
The Pitman-Yor, or Chinese restaurant process, is a stochastic process that generates distributions following a power law with exponents lower than 2, as found in numerous physical, biological, technological, and social systems. We discuss its rich behavior with the tools and viewpoint of statistical mechanics. We show that this process invariably gives rise to a condensation, i.e., a distribution dominated by a finite number of classes. We also evaluate thoroughly the finite-size effects, finding that the lack of stationary state and self-averaging of the process creates realization-dependent cutoffs and behavior of the distributions with no equivalent in other statistical mechanical models.
Samerdokiene, Vitalija; Mastauskas, Albinas; Atkocius, Vydmantas
2015-12-01
The use of radiation sources for various medical purposes is closely related to irradiation of the medical staff, which causes harmful effects to health and an increased risk of cancer. In total, 1463 medical staff who have been occupationally exposed to sources of ionising radiation (IR) had been monitored. Records with annual dose measurements (N = 19 157) were collected and regularly analysed for a 23-y period: from 01 January 1991 to 31 December 2013. The collected annual average effective dose (AAED) data have been analysed according to different socio-demographic parameters and will be used in future investigation in order to assess cancer risk among medical staff occupationally exposed to sources of IR. A thorough analysis of data extracted from medical staff's dose records allows one to conclude that the average annual effective dose of Lithuanian medical staff occupationally exposed to sources of IR was consistently decreased from 1991 (1.75 mSv) to 2013 (0.27 mSv) (p < 0.0001). PMID:25614631
A statistical study of gyro-averaging effects in a reduced model of drift-wave transport
da Fonseca, J D; Sokolov, M; Caldas, I L
2016-01-01
A statistical study of finite Larmor radius (FLR) effects on transport driven by electrostatic drift-waves is presented. The study is based on a reduced discrete Hamiltonian dynamical system known as the gyro-averaged standard map (GSM). In this system, FLR effects are incorporated through the gyro-averaging of a simplified weak-turbulence model of electrostatic fluctuations. Formally, the GSM is a modified version of the standard map in which the perturbation amplitude, $K_0$, becomes $K_0 J_0(\\hat{\\rho})$, where $J_0$ is the zeroth-order Bessel function and $\\hat{\\rho}$ is the Larmor radius. Assuming a Maxwellian probability density function (pdf) for $\\hat{\\rho}$, we compute analytically and numerically the pdf and the cumulative distribution function of the effective drift-wave perturbation amplitude $K_0 J_0(\\hat{\\rho})$. Using these results we compute the probability of loss of confinement (i.e., global chaos), $P_{c}$, and the probability of trapping in the main drift-wave resonance, $P_{t}$. It is sho...
The use of radiation sources for various medical purposes is closely related to irradiation of the medical staff, which causes harmful effects to health and an increased risk of cancer. In total, 1463 medical staff who have been occupationally exposed to sources of ionising radiation (IR) had been monitored. Records with annual dose measurements (N = 19 157) were collected and regularly analysed for a 23-y period: from 01 January 1991 to 31 December 2013. The collected annual average effective dose (AAED) data have been analysed according to different socio-demographic parameters and will be used in future investigation in order to assess cancer risk among medical staff occupationally exposed to sources of IR. A thorough analysis of data extracted from medical staff's dose records allows one to conclude that the average annual effective dose of Lithuanian medical staff occupationally exposed to sources of IR was consistently decreased from 1991 (1.75 mSv) to 2013 (0.27 mSv) (p < 0.0001). (authors)
It is proposed to use a generalized matrix averaging (GMA) method for calculating the parameters of an effective medium with physical properties equivalent to those of a set of thin multiferroic layers. This approach obviates the need to solve a complex system of magnetoelectroelasticity equations. The required effective characteristics of a system of multiferroic layers are obtained using only operations with matrices, which significantly simplifies calculations and allows multilayer systems to be described. The proposed approach is applicable to thin-layer systems, in which the total thickness is much less than the system length, radius of curvature, and wavelengths of waves that can propagate in the system (long-wave approximation). Using the GMA method, it is also possible to obtain the effective characteristics of a periodic structure with each period comprising a number of thin multiferroic layers
Starkov, A. S. [St. Petersburg National Research University of Information Technologies, Mechanics and Optics, Institute of Refrigeration and Biotechnology (Russian Federation); Starkov, I. A., E-mail: ferroelectrics@ya.ru [Brno University of Technology, SIX Research Centre (Czech Republic)
2014-11-15
It is proposed to use a generalized matrix averaging (GMA) method for calculating the parameters of an effective medium with physical properties equivalent to those of a set of thin multiferroic layers. This approach obviates the need to solve a complex system of magnetoelectroelasticity equations. The required effective characteristics of a system of multiferroic layers are obtained using only operations with matrices, which significantly simplifies calculations and allows multilayer systems to be described. The proposed approach is applicable to thin-layer systems, in which the total thickness is much less than the system length, radius of curvature, and wavelengths of waves that can propagate in the system (long-wave approximation). Using the GMA method, it is also possible to obtain the effective characteristics of a periodic structure with each period comprising a number of thin multiferroic layers.
Boland, T M; Quinlan, C; Pierce, K M; Lynch, M B; Kenny, D A; Kelly, A K; Purcell, P J
2013-08-01
The objective of this study was to determine the effect of pregrazing pasture herbage mass (HM) on CH4 emissions, ruminal fermentation, and ADG of grazing beef heifers at 2 stages of the grazing season. Thirty Limousin cross heifers were allocated to 1 of 2 target pregrazing HM treatments [a low HM (LHM) or high HM (HHM) treatment] for 126 d in a randomized block design experiment. Pasture herbage and heifer rumen fluid samples were collected, and enteric CH4 emissions were determined using an SF6 tracer technique during two 5-d measurement periods [MP; MP 1 (25 to 29 May) and MP 2 (6 to 10 September)]. Both DMI and GE intake (GEI) were measured during MP 2, and ADG of the heifers was measured every 14 d throughout the 126-d grazing period. Mean HM for the LHM and HHM treatments were 1,300 and 2,000 kg DM/ha, respectively, during MP 1 and 2,800 and 3,200 kg DM/ha, respectively, during MP 2. The CP concentration of the offered herbage was greater (P 0.10) in the NDF concentration of the herbage was found between the HM treatments during MP 1 or 2. There was no effect (P > 0.10) of HM treatment on total CH4 emissions (g/d) for either MP [mean value across HM treatments of 121 (SED 5.4) g/d during MP 1 and 132 (8.8) g/d during MP 2], but CH4 emissions (g) per kilogram of ADG were reduced (P 0.10) in DMI or GEI of the heifers between the HM treatments. The results of this study suggest that offering a low pregrazing HM sward will reduce enteric CH4 emissions relative to ADG throughout the grazing season because of increased ADG. PMID:23908161
Purpose: This study explores novel methods to address two significant challenges affecting measurement of patient-specific quality assurance (QA) with IBA’s Matrixx Evolution™ ionization chamber array. First, dose calculation algorithms often struggle to accurately determine dose to the chamber array due to CT artifact and algorithm limitations. Second, finite chamber size and volume averaging effects cause additional deviation from the calculated dose. Methods: QA measurements were taken with the Matrixx positioned on the treatment table in a solid-water Multi-Cube™ phantom. To reduce the effect of CT artifact, the Matrixx CT image set was masked with appropriate materials and densities. Individual ionization chambers were masked as air, while the high-z electronic backplane and remaining solid-water material were masked as aluminum and water, respectively. Dose calculation was done using Varian’s Acuros XB™ (V11) algorithm, which is capable of predicting dose more accurately in non-biologic materials due to its consideration of each material’s atomic properties. Finally, the exported TPS dose was processed using an in-house algorithm (MATLAB) to assign the volume averaged TPS dose to each element of a corresponding 2-D matrix. This matrix was used for comparison with the measured dose. Square fields at regularly-spaced gantry angles, as well as selected patient plans were analyzed. Results: Analyzed plans showed improved agreement, with the average gamma passing rate increasing from 94 to 98%. Correction factors necessary for chamber angular dependence were reduced by 67% compared to factors measured previously, indicating that previously measured factors corrected for dose calculation errors in addition to true chamber angular dependence. Conclusion: By comparing volume averaged dose, calculated with a capable dose engine, on a phantom masked with correct materials and densities, QA results obtained with the Matrixx Evolution™ can be significantly
Fugal, M; McDonald, D; Jacqmin, D; Koch, N; Ellis, A; Peng, J; Ashenafi, M; Vanek, K [Medical University of South Carolina, Charleston, SC (United States)
2015-06-15
Purpose: This study explores novel methods to address two significant challenges affecting measurement of patient-specific quality assurance (QA) with IBA’s Matrixx Evolution™ ionization chamber array. First, dose calculation algorithms often struggle to accurately determine dose to the chamber array due to CT artifact and algorithm limitations. Second, finite chamber size and volume averaging effects cause additional deviation from the calculated dose. Methods: QA measurements were taken with the Matrixx positioned on the treatment table in a solid-water Multi-Cube™ phantom. To reduce the effect of CT artifact, the Matrixx CT image set was masked with appropriate materials and densities. Individual ionization chambers were masked as air, while the high-z electronic backplane and remaining solid-water material were masked as aluminum and water, respectively. Dose calculation was done using Varian’s Acuros XB™ (V11) algorithm, which is capable of predicting dose more accurately in non-biologic materials due to its consideration of each material’s atomic properties. Finally, the exported TPS dose was processed using an in-house algorithm (MATLAB) to assign the volume averaged TPS dose to each element of a corresponding 2-D matrix. This matrix was used for comparison with the measured dose. Square fields at regularly-spaced gantry angles, as well as selected patient plans were analyzed. Results: Analyzed plans showed improved agreement, with the average gamma passing rate increasing from 94 to 98%. Correction factors necessary for chamber angular dependence were reduced by 67% compared to factors measured previously, indicating that previously measured factors corrected for dose calculation errors in addition to true chamber angular dependence. Conclusion: By comparing volume averaged dose, calculated with a capable dose engine, on a phantom masked with correct materials and densities, QA results obtained with the Matrixx Evolution™ can be significantly
N. G. Vlasova
2012-01-01
Full Text Available Catalogue of the average annual effective exposure doses of the inhabitants of the territories contaminated due to the Chernobul accident had been developed according to the method of the assessment of the average annual effective exposure doses of the settlements inhabitants. The cost-efficacy of the use of the average annual effective dose assessment method was 250 000 USD for the current 5 years. Average annual effective dose exceeded 1 mSv/year for 191 Belarus settlements from 2613. About 50 000 persons are living in these settlements.
The Treatment Effectiveness Assessment (TEA
Ling W
2013-09-01
Full Text Available Walter Ling,1 David Farabee,1 Dagmar Liepa,2 Li-Tzy Wu3 1Integrated Substance Abuse Programs, University of California, Los Angeles, CA, 2Valley Care Medical Center, Panorama City, CA, 3Department of Psychiatry and Behavioral Sciences, School of Medicine, Duke University Medical Center, Durham, NC, USA We have been surprised and gratified by the readers’ responses to our article, The Treatment Effectiveness Assessment (TEA: an efficient, patient-centered instrument for evaluating progress in recovery from addiction, which was published in December 2012.1 In the six months since that time, we have received numerous questions and observations about the article, and about the TEA instrument. Respondents were clinicians: physicians, counselors, therapists, nurses; as well as administrators and policy makers. View original paper by Ling W, Farabee D, Liepa D, Wu LT.
Managave, S. R.; Jani, R. A.; Narayana Rao, T.; Sunilkumar, K.; Satheeshkumar, S.; Ramesh, R.
2016-08-01
Evaporation of rain is known to contribute water vapor, a potent greenhouse gas, to the atmosphere. Stable oxygen and hydrogen isotopic compositions (δ18O and, δD, respectively) of precipitation, usually measured/presented as values integrated over rain events or monthly mean values, are important tools for detecting evaporation effects. The slope ~8 of the linear relationship between such time-averaged values of δD and δ18O (called the meteoric water line) is widely accepted as a proof of condensation under isotopic equilibrium and absence of evaporation of rain during atmospheric fall. Here, through a simultaneous investigation of the isotopic and drop size distributions of seventeen rain events sampled on an intra-event scale at Gadanki (13.5°N, 79.2°E), southern India, we demonstrate that the evaporation effects, not evident in the time-averaged data, are significantly manifested in the sub-samples of individual rain events. We detect this through (1) slopes significantly less than 8 for the δD-δ18O relation on intra-event scale and (2) significant positive correlations between deuterium excess ( d-excess = δD - 8*δ18O; lower values in rain indicate evaporation) and the mass-weighted mean diameter of the raindrops ( D m ). An estimated ~44 % of rain is influenced by evaporation. This study also reveals a signature of isotopic equilibration of rain with the cloud base vapor, the processes important for modeling isotopic composition of precipitation. d-excess values of rain are modified by the post-condensation processes and the present approach offers a way to identify the d-excess values least affected by such processes. Isotope-enabled global circulation models could be improved by incorporating intra-event isotopic data and raindrop size dependent isotopic effects.
Managave, S. R.; Jani, R. A.; Narayana Rao, T.; Sunilkumar, K.; Satheeshkumar, S.; Ramesh, R.
2015-11-01
Evaporation of rain is known to contribute water vapor, a potent greenhouse gas, to the atmosphere. Stable oxygen and hydrogen isotopic compositions (δ18O and, δD, respectively) of precipitation, usually measured/presented as values integrated over rain events or monthly mean values, are important tools for detecting evaporation effects. The slope ~8 of the linear relationship between such time-averaged values of δD and δ18O (called the meteoric water line) is widely accepted as a proof of condensation under isotopic equilibrium and absence of evaporation of rain during atmospheric fall. Here, through a simultaneous investigation of the isotopic and drop size distributions of seventeen rain events sampled on an intra-event scale at Gadanki (13.5°N, 79.2°E), southern India, we demonstrate that the evaporation effects, not evident in the time-averaged data, are significantly manifested in the sub-samples of individual rain events. We detect this through (1) slopes significantly less than 8 for the δD-δ18O relation on intra-event scale and (2) significant positive correlations between deuterium excess (d-excess = δD - 8*δ18O; lower values in rain indicate evaporation) and the mass-weighted mean diameter of the raindrops (D m ). An estimated ~44 % of rain is influenced by evaporation. This study also reveals a signature of isotopic equilibration of rain with the cloud base vapor, the processes important for modeling isotopic composition of precipitation. d-excess values of rain are modified by the post-condensation processes and the present approach offers a way to identify the d-excess values least affected by such processes. Isotope-enabled global circulation models could be improved by incorporating intra-event isotopic data and raindrop size dependent isotopic effects.
The activity concentration of natural radionuclides and 222Rn (Radon) exhalation rate in soil samples were determined using NaI Scintillation detector and Scintillation Radon Monitor. Soil samples were collected from different geological formations of the same area. The average value of 226Ra (Radium) equivalent activity in soil samples of the studied area was 124.9 Bq kg-1. 226Ra equivalent activities was calculated for the analyzed samples to assess the radiation hazards arising due to the use of these soil samples in the construction of dwellings. The 222Rn exhalation rate in the studied area was varied from 6.9 ± 0.2 mBq Kg-1 h-1 to 33.2 ± 2 mBq Kg-1. A positive correlation was obtained between the Ra (Radium) and 222Rn exhalation rate. The overall average annual effective dose in the studied is lower than the world recommended value of 1.0 mSva-1. (author)
Iverson, Richard M.; George, David L.
2014-01-01
To simulate debris-flow behaviour from initiation to deposition, we derive a depth-averaged, two-phase model that combines concepts of critical-state soil mechanics, grain-flow mechanics and fluid mechanics. The model's balance equations describe coupled evolution of the solid volume fraction, m, basal pore-fluid pressure, flow thickness and two components of flow velocity. Basal friction is evaluated using a generalized Coulomb rule, and fluid motion is evaluated in a frame of reference that translates with the velocity of the granular phase, vs. Source terms in each of the depth-averaged balance equations account for the influence of the granular dilation rate, defined as the depth integral of ∇⋅vs. Calculation of the dilation rate involves the effects of an elastic compressibility and an inelastic dilatancy angle proportional to m−meq, where meq is the value of m in equilibrium with the ambient stress state and flow rate. Normalization of the model equations shows that predicted debris-flow behaviour depends principally on the initial value of m−meq and on the ratio of two fundamental timescales. One of these timescales governs downslope debris-flow motion, and the other governs pore-pressure relaxation that modifies Coulomb friction and regulates evolution of m. A companion paper presents a suite of model predictions and tests.
Effect of sorbent hydration on the average activity of CaO in a Ca-looping system
Arias, B.; Grasa, G.S.; Abanades, J.C. [CSIC, Oviedo (Spain)
2010-10-01
It is well known that the solid sorbents used in calcium looping CO{sub 2} capture systems experience a reduction in carrying capacity with the number of cycles. Several sorbent reactivation schemes have been proposed as means of overcoming this deactivation process. This work analyzes the integration of a reactivation process in a Ca-looping cycle by means of a hydration reactor. The mass balances involved in this three-reactor systems must then be solved in order to evaluate the effect of the different variables on the average activity of the sorbent. The positive impact of reactivation by hydration (i.e. average increase in activity of the sorbent arriving at the carbonator) is discussed in conjunction with the negative impacts on the overall operation of the system (e.g. steam consumption, etc.) and on the large reactivation reactors. Two different scenarios employing different degrees of hydration have been evaluated. The results obtained show that steam is used more efficiently when only a small fraction of the circulating solids is hydrated to a high degree. Moreover, the performance of the sorbent reactivation step is better when low make up flows of limestone are used.
Averaging anisotropic cosmologies
Barrow, J D; Barrow, John D.; Tsagas, Christos G.
2006-01-01
We examine the effects of spatial inhomogeneities on irrotational anisotropic cosmologies by looking at the average properties of pressure-free Bianchi-type models. Adopting the Buchert averaging scheme, we identify the kinematic backreaction effects by focussing on spacetimes with zero or isotropic spatial curvature. This allows us to close the system of the standard scalar formulae with a propagation equation for the shear magnitude. We find no change in the already known conditions for accelerated expansion. The backreaction terms are expressed as algebraic relations between the mean-square fluctuations of the models' irreducible kinematical variables. Based on these we investigate the early evolution of averaged vacuum Bianchi type $I$ universes and those filled with pressureless matter. In the latter case we show that the backreaction effects can modify the familiar Kasner-like singularity and potentially remove Mixmaster-type oscillations. We also discuss the possibility of accelerated expansion due to ...
The previous formalism for dealing with the average effect of a highly supersonic turbulent gravito-hydrodynamic field in the hadron era of the universe is extended so as to take into consideration various dissipative processes in the hadronic substratum. After a phenomenological fixation of the coefficients of bulk viscosity, shear viscosity and heat conduction, it is shown that those dissipative processes have a considerable influence upon the three characteristic mean-value quantities (at the bounce epoch of our regular model-universe) corresponding to metric, velocity and density fluctuations. A possibility of fixing the dissipation coefficients of the hadronic matter under consideration, i.e., the one based on the concept of statistical bootstrap, in a more well-founded manner is also conjectured. (auth.)
Gal-Chen, T.; Wyngaard, J. C.
1982-01-01
Calculations of the ratio of the true one-dimensional spectrum of vertical velocity and that measured with multiple-Doppler radar beams are presented. It was assumed that the effects of pulse volume averaging and objective analysis routines is replacement of a point measurement with a volume integral. A u and v estimate was assumed to be feasible when orthogonal radars are not available. Also, the target fluid was configured as having an infinite vertical dimension, zero vertical velocity at the top and bottom, and having homogeneous and isotropic turbulence with a Kolmogorov energy spectrum. The ratio obtained indicated that equal resolutions among radars yields a monotonically decreasing, wavenumber-dependent response function. A gain of 0.95 was demonstrated in an experimental situation with 40 levels. Possible errors introduced when using unequal resolution radars were discussed. Finally, it was found that, for some flows, the extent of attenuation depends on the number of vertical levels resolvable by the radars.
Kravdal Øystein
2009-12-01
Full Text Available Abstract Background The intention was to find out whether there was an association between the socio-economic resources in a small neighbourhood ("basic statistical unit"; BSU and individual mortality, net of individual resources, and whether this association differed between municipalities including a quite large city and others. The possibility of a rural-urban difference in the health effect of community resources has not been checked earlier. Methods Discrete-time hazard models for mortality at age 60-89 were estimated for 1990-1992 and 2000-2002, using register data that cover the entire Norwegian population. For each person, the educational level and the municipality and BSU of residence in 1990 and 2000 were known. Average education was computed by aggregating over the individual data. In total, there were about 200000 deaths in more than 13000 BSUs during 5 million person-years of observation. Results There was a significant relationship between average education in the BSU and individual mortality, but only in the medium-sized and largest municipalities. The sharpest relationship was seen in the latter, where for example OR per year of education was 0.908 (95% CI 0.887-0.929 in the 1990-92 period. The findings were robust to various alternative specifications. Conclusion These results from a large data set are consistent with the idea that neighbourhood socio-economic resources may affect individual mortality, but suggest that distinctions according to population size or density be made in future research and that one should be careful, if focusing on cities, to generalize beyond that setting. With these data, one can only speculate about the reasons for the rural-urban difference. A stronger higher-level spatial segregation in urban areas may be one explanation.
Shu, Di; Guo, Lei; Yin, Liang; Chen, Zhaoyang; Chen, Juan; Qi, Xin
2015-11-01
The average volume of magnetic Barkhausen jump (AVMBJ) v bar generated by magnetic domain wall irreversible displacement under the effect of the incentive magnetic field H for ferromagnetic materials and the relationship between irreversible magnetic susceptibility χirr and stress σ are adopted in this paper to study the theoretical relationship among AVMBJ v bar(magneto-elasticity noise) and the incentive magnetic field H. Then the numerical relationship among AVMBJ v bar, stress σ and the incentive magnetic field H is deduced. Utilizing this numerical relationship, the displacement process of magnetic domain wall for single crystal is analyzed and the effect of the incentive magnetic field H and the stress σ on the AVMBJ v bar (magneto-elasticity noise) is explained from experimental and theoretical perspectives. The saturation velocity of Barkhausen jump characteristic value curve is different when tensile or compressive stress is applied on ferromagnetic materials, because the resistance of magnetic domain wall displacement is different. The idea of critical magnetic field in the process of magnetic domain wall displacement is introduced in this paper, which solves the supersaturated calibration problem of AVMBJ - σ calibration curve.
Germann, Paul J.
The directed-inquiry approach to learning science process skills and scientific problem solving [DIAL(SPS)2] was developed to help high-school students gain the critical thinking skills required to solve problems in the biology lab. This curriculum integrated several learning strategies into a single approach: advance organizers, the learning cycle, concept maps, Vee diagrams, a focusing strategy, and writing. Two general questions were addressed. First, was the DIAL(SPS)2 treatment more effective than a conventional treatment? Second, was there evidence of an aptitude-treatment interaction? Four high-school biology classes taught by this investigator were used to test the DIAL(SPS)2 curriculum. Scheduling of students involved ability grouping. To test the curriculum in the most rigorous way, the experimental group consisted of average ability students and the comparison group consisted of above-average students. Both the groups were pretested in August and posttested in May. In the intervening time, the experimental group received the DIAL(SPS)2 treatment while the comparison group received a more traditional approach. Analysis of covariance revealed that the DIAL(SPS)2 curriculum had no significant effect on the learning of science process skills or on cognitive development. Aptitude-treatment interaction analyses revealed an interaction of DIAL(SPS)2 treatment and cognitive development.
Gibbison, Godfrey A.; Henry, Tracyann L.; Perkins-Brown, Jayne
2011-01-01
Freshman grade point average, in particular first semester grade point average, is an important predictor of survival and eventual student success in college. As many institutions of higher learning are searching for ways to improve student success, one would hope that policies geared towards the success of freshmen have long term benefits…
Sadoun, Raphael; Choi, Jun-Hwan; Romano-Díaz, Emilio
2015-01-01
We use high-resolution cosmological zoom-in simulations in order to analyze galaxy evolution at redshifts z~6-12 in highly-overdense 5 sigma density peaks. Strong stellar feedback, in the form of galactic winds, is expected to play an important role in the evolution of these regions. We investigate the effects of these winds by comparing different galactic outflow prescriptions, including (i) a constant velocity model (CW), (ii) a variable velocity model scaling with galaxy properties (VW), and (iii) a model with no outflows (NW). The CW model is also applied to a simulation of an average density region to study the impact of environment on galaxy evolution. A direct consequence of the overdensity is a shallow galaxy mass function slope at the low-mass end and an accelerated evolution of dark matter and baryonic structures. The overdensity hosts massive haloes, up to ~10^{12} Msun, with embedded galaxies up to ~10^{11} Msun in stellar mass by z~6, which are absent in the "normal" region. The CW model leads to...
J. Xamán
2012-06-01
Full Text Available In this paper a theoretical study on conjugated heat transfer (natural convection, radiation and conduction in a squareroom (cavity with turbulent flow is presented, taking into account variation on the opaque wall emissivity. The room isformed by an isothermal vertical wall, two adiabatic horizontal walls and a semitransparent wall with and without acontrol solar radiation film. The governing equations for turbulent flow in 2D were solved using a finite volumeformulation and k- turbulent model. Results for an isothermal wall at 21°C and an external temperature of 35°C arepresented. The size of the room is 4.0 m length and height and the solar radiation falling directly on thesemitransparent wall was 750 W/m2 (AM2. The emissivity of the opaque walls was varied between 0.1 ≤ * ≤ 1.0.Results show that, based on the air average temperature and the effective heat flux inside the room, the solar controlfilm under study was advantageous for energy saving purposes, for emissivity values of * ≤ 0.46. A correlation onthis system for the heat transfer as a function of the emissivities was determined.
Hu, Wu-Yueh
2012-01-01
In the literature, the effect of contract farming on the productivity efficiency or profitability is rarely studied, especially in the crop sector. In this paper, we use a farm-level dataset (Agriculture and Resource Management Survey) to examine the effect of contract farming on the farmers' average return for the corn, soybean and wheat producers. The results of the matching estimation show that without matching, the effect of contract farming on the average returns of the corn and soybean ...
Rafa, S. Molins; Trebotich, D.; Steefel, C. I.; Shen, C.
2012-02-01
The scale-dependence of geochemical reaction rates hinders their use in continuum scale models intended for the interpretation and prediction of chemical fate and transport in subsurface environments such as those considered for geologic sequestration of CO{sub 2}. Processes that take place at the pore scale, especially those involving mass transport limitations to reactive surfaces, may contribute to the discrepancy commonly observed between laboratory-determined and continuum-scale or field rates. Here, the dependence of mineral dissolution rates on the pore structure of the porous media is investigated by means of pore scale modeling of flow and multicomponent reactive transport. The pore scale model is comprised of high performance simulation tools and algorithms for incompressible flow and conservative transport combined with a general-purpose multicomponent geochemical reaction code. The model performs direct numerical simulation of reactive transport based on an operator-splitting approach to coupling transport and reactions. The approach is validated with a Poiseuille flow single-pore experiment and verified with an equivalent 1D continuum-scale model of a capillary tube packed with calcite spheres. Using the case of calcite dissolution as an example, the high resolution model is used to demonstrate that non-uniformity in the flow field at the pore scale has the effect of decreasing the overall reactivity of the system, even when systems with identical reactive surface area are considered. The effect becomes more pronounced as the heterogeneity of the reactive grain packing increases, particularly where the flow slows sufficiently such that the solution approaches equilibrium locally and the average rate becomes transport-limited.
N. G. Vlasova
2016-01-01
Full Text Available In an existing exposure situation (in a remote period after the Chernobyl accident there is a need of the transition from "radioactive area zoning" to "the settlements classification by average annual effective doses to the critical group of persons among the settlement's residents", to ensure the appropriate radiation level and social protection of the settlement's residents, located on the contaminated territory.The comparative allocation analysis of the average annual external and internal effective doses, the average annual effective cumulative doses to residents of settlements, related to the relevant areas (the Council of Ministers of Belarus latest decision, the proposed dose range according to the Catalogue of average annual effective doses of residents of settlements radiation Republic of Belarus confirmed the validity of the transition from "radioactive zoning area" to "the classification of settlements by average annual effective dose."In accordance with the radiation protection principles, it seems reasonable to classify the settlements located on the contaminated territory at the average annual effective dose as follows: < 0.1 mSv / year (not required to carry out radiation protection measures in the agricultural sector; 0.1-1 mSv / year (periodic radiation monitoring should be carried out; 1 mSv / year (it is necessary to apply a complex of protective measures.
EFFECT OF SURFACE TREATMENT ON ENAMEL SURFACE ROUGHNESS
Şeyda Erşahan
2016-01-01
Full Text Available Purpose: To compare the effects of different methods of surface treatment on enamel roughness. Materials and Methods: Ninety human maxillary first premolars were randomly divided into three groups (n=30 according to type of enamel surface treatment: I, acid etching; II, Er:YAG laser; III, Nd:YAG laser. The surface roughness of enamel was measured with a noncontact optical profilometer. For each enamel sample, two readings were taken across the sample—before enamel surface treatment (T1 and after enamel surface treatment (T2. The roughness parameter analyzed was the average roughness (Ra. Statistical analysis was performed using a Paired sample t test and the post-hoc Mann- Whitney U test, with the significance level set at 0.05. Results: The highest Ra (average roughness values were observed for Group II, with a significant difference with Groups I and III (P<0.001. Ra values for the acid etching group (Group I were significantly lower than other groups (P<0.001. Conclusion: Surface treatment of enamel with Er:YAG laser and Nd:YAG laser results in significantly higher Ra than acid-etching. Both Er:YAG laser or Nd:YAG laser can be recommended as viable treatment alternatives to acid etching.
Chaney, Bradford
2016-01-01
The primary technique that many researchers use to analyze data from randomized control trials (RCTs)--detecting the average treatment effect (ATE)--imposes assumptions upon the data that often are not correct. Both theory and past research suggest that treatments may have significant impacts on subgroups even when showing no overall effect.…
The relationship between body weight gain and the onset of bone aberrations (e.g. epiphysitis) is described. A model was derived which described the increase in transverse epiphyseal width, and the major factor found to affect epiphyseal width was average daily gain in body weight. In addition, a radiographic examination of the epiphyseal areas showed a larger number of bone aberrations in groups gaining weight at an above-average rate. Thus, a rapid increase in body weight can be suggested as a significant factor in the onset of epiphysitis
Yao-Ching Wang
Full Text Available Respiratory motion causes uncertainties in tumor edges on either computed tomography (CT or positron emission tomography (PET images and causes misalignment when registering PET and CT images. This phenomenon may cause radiation oncologists to delineate tumor volume inaccurately in radiotherapy treatment planning. The purpose of this study was to analyze radiology applications using interpolated average CT (IACT as attenuation correction (AC to diminish the occurrence of this scenario. Thirteen non-small cell lung cancer patients were recruited for the present comparison study. Each patient had full-inspiration, full-expiration CT images and free breathing PET images by an integrated PET/CT scan. IACT for AC in PET(IACT was used to reduce the PET/CT misalignment. The standardized uptake value (SUV correction with a low radiation dose was applied, and its tumor volume delineation was compared to those from HCT/PET(HCT. The misalignment between the PET(IACT and IACT was reduced when compared to the difference between PET(HCT and HCT. The range of tumor motion was from 4 to 17 mm in the patient cohort. For HCT and PET(HCT, correction was from 72% to 91%, while for IACT and PET(IACT, correction was from 73% to 93% (*p<0.0001. The maximum and minimum differences in SUVmax were 0.18% and 27.27% for PET(HCT and PET(IACT, respectively. The largest percentage differences in the tumor volumes between HCT/PET and IACT/PET were observed in tumors located in the lowest lobe of the lung. Internal tumor volume defined by functional information using IACT/PET(IACT fusion images for lung cancer would reduce the inaccuracy of tumor delineation in radiation therapy planning.
Late effects after treatment for Hodgkin lymphoma
Daniëls, Laurien Aletta
2014-01-01
Although modern treatment strategies have made Hodgkin Lymphoma (HL) a highly curable disease, there is a life-long increased risk of morbidity and mortality due to treatment. Over time it has become increasingly evident that the historically used extensive treatment fields can potentially lead to numerous long-term adverse effects, often presenting clinically with a delay of more than 10-15 years. Epidemiological studies have shown an increased risks of second malignancies in HL survivors. H...
Cost-Effective Fuel Treatment Planning
Kreitler, J.; Thompson, M.; Vaillant, N.
2014-12-01
The cost of fighting large wildland fires in the western United States has grown dramatically over the past decade. This trend will likely continue with growth of the WUI into fire prone ecosystems, dangerous fuel conditions from decades of fire suppression, and a potentially increasing effect from prolonged drought and climate change. Fuel treatments are often considered the primary pre-fire mechanism to reduce the exposure of values at risk to wildland fire, and a growing suite of fire models and tools are employed to prioritize where treatments could mitigate wildland fire damages. Assessments using the likelihood and consequence of fire are critical because funds are insufficient to reduce risk on all lands needing treatment, therefore prioritization is required to maximize the effectiveness of fuel treatment budgets. Cost-effectiveness, doing the most good per dollar, would seem to be an important fuel treatment metric, yet studies or plans that prioritize fuel treatments using costs or cost-effectiveness measures are absent from the literature. Therefore, to explore the effect of using costs in fuel treatment planning we test four prioritization algorithms designed to reduce risk in a case study examining fuel treatments on the Sisters Ranger District of central Oregon. For benefits we model sediment retention and standing biomass, and measure the effectiveness of each algorithm by comparing the differences among treatment and no treat alternative scenarios. Our objective is to maximize the averted loss of net benefits subject to a representative fuel treatment budget. We model costs across the study landscape using the My Fuel Treatment Planner software, tree list data, local mill prices, and GIS-measured site characteristics. We use fire simulations to generate burn probabilities, and estimate fire intensity as conditional flame length at each pixel. Two prioritization algorithms target treatments based on cost-effectiveness and show improvements over those
Impact of Treatment Integrity on Intervention Effectiveness
Fryling, Mitch J.; Wallace, Michele D.; Yassine, Jordan N.
2012-01-01
Treatment integrity has cogent implications for intervention effectiveness. Understanding these implications is an important, but often neglected, undertaking in behavior analysis. This paper reviews current research on treatment integrity in applied behavior analysis. Specifically, we review research evaluating the relation between integrity…
IMPACT OF TREATMENT INTEGRITY ON INTERVENTION EFFECTIVENESS
Fryling, Mitch J; Wallace, Michele D; Yassine, Jordan N
2012-01-01
Treatment integrity has cogent implications for intervention effectiveness. Understanding these implications is an important, but often neglected, undertaking in behavior analysis. This paper reviews current research on treatment integrity in applied behavior analysis. Specifically, we review research evaluating the relation between integrity failures and the efficacy of behavioral interventions. Avenues for future research are provided.
Effective treatments for social anxiety disorder
Carolina Baeza
2007-01-01
Social Anxiety Disorder (SAD), also known as Social Phobia, is now recognised as a chronicand disabling psychiatric condition. The high prevalence and clinical significance of the disease emphasize the need for early recognition and effective treatment. The main current treatment will be presented paying special attention to meta-analyses and studies, which try to differentiate types of interventions, by their efficacy.
Khan, A R; Tewari, S. K.; Shukla, A.N.
2007-01-01
This paper has examined (i) the nature and extent of inter-state disparities in per hectare flow of short-term institutional credit to agriculture, and (ii) its relationship with average cost of cultivation across states. It has covered all the six regions of the country comprising seventeen agriculturally most important states having about 96 per cent agricultural land in the country. It has revealed that inter-regional disparities in per hectare flow of institutional credit as measured thro...
Treatment Effect Heterogeneity in Theory and Practice
Angrist, Joshua D.
2003-01-01
Instrumental Variables (IV) methods identify internally valid causal effects for individuals whose treatment status is manipulable by the instrument at hand. Inference for other populations requires some sort of homogeneity assumption. This paper outlines a theoretical framework that nests all possible homogeneity assumptions for a causal treatment-effects model with a binary instrument. The framework suggests strategies for using IV estimates for extrapolation, while making it clear that eff...
Average Range and Network Synchronizability
The influence of structural properties of a network on the network synchronizability is studied by introducing a new concept of average range of edges. For both small-world and scale-free networks, the effect of average range on the synchronizability of networks with bounded or unbounded synchronization regions is illustrated through numerical simulations. The relations between average range, range distribution, average distance, and maximum betweenness are also explored, revealing the effects of these factors on the network synchronizability of the small-world and scale-free networks, respectively. (general)
Negative Effects from Psychological Treatments: A Perspective
Barlow, David H.
2010-01-01
The author offers a 40-year perspective on the observation and study of negative effects from psychotherapy or psychological treatments. This perspective is placed in the context of the enormous progress in refining methodologies for psychotherapy research over that period of time, resulting in the clear demonstration of positive effects from…
Stef Iulian Ioan
2013-05-01
Full Text Available In the upper basin of the Sebes Valley, the oldest storage lakes have been temporary artificial lakes, called haituri in Romanian. They were created within the forest exploitation areas. Inside the dams of those retention lakes, which dams are made of a wooden skeleton, filled with soil and stones, there have been weirs for the quick discharge of the water, having the purpose of creating some flood trends, capable of carrying over the logs, downstream the lake. At present, some of those temporary artificial lakes are used as trout farms, while others are damaged, or operate as basins for the sedimentation of the alluvial deposits. The difference of level between the springs of the Sebes and the Mures Rivers generates a convertible hydroelectric potential, having an average power exceeding 60,000 kW" />
The principles of resonance averaging as applied to neutron capture reactions are described. Several illustrations of resonance averaging to problems of nuclear structure and the distribution of radiative strength in nuclei are provided. 30 refs., 12 figs
Obesity in Family Practice: Is Treatment Effective?
Sanborn, Margaret D.; Manske, Stephen R.; Schlegel, Ronald P.
1983-01-01
Obesity is a common condition which has important effects on health status and longevity. This review examines the efficacy of treatments for both moderate and severe obesity. A plan of treatment combining diet, exercise, and behavioral strategies is outlined. Surgery and its complications are reviewed. Eight management issues, including rate of weight loss, self-help groups, and fringe therapies, are presented. Management recommendations are based on a critical review of the weight loss lite...
Mishra, Priti
2014-01-01
Since the advent of the accelerated expanding homogeneous universe model, some other explanations for the supernova Ia dimming have been explored, among which there are inhomogeneous models constructed with exact $\\Lambda = 0$ solutions of Einstein's equations. They have been used either as one patch or to build Swiss-cheese models. The most studied ones have been the Lema\\^itre-Tolman-Bondi (LTB) models. However, these models being spatially spherical, they are not well designed to reproduce the large scale structures which exhibit clusters, filaments and non spherical voids. This is the reason why Szekeres models, which are devoid of any symmetry, have recently come into play. In this paper, we give the equations and an algorithm to compute the redshift-drift for the most general quasi-spherical Szekeres (QSS) models with no dark energy. We apply it to a QSS model recently proposed by Bolejko and Sussman (BSQSS model) who averaged their model to reproduce the density distribution of the Alexander and collab...
Barraclough, B; Lebron, S [J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL (United States); Li, J; Fan, Qiyong; Liu, C; Yan, G [Department of Radiation Oncology, University of Florida, Gainesville, FL (United States)
2015-06-15
Purpose: A novel convolution-based approach has been proposed to address ion chamber (IC) volume averaging effect (VAE) for the commissioning of commercial treatment planning systems (TPS). We investigate the use of various convolution kernels and its impact on the accuracy of beam models. Methods: Our approach simulates the VAE by iteratively convolving the calculated beam profiles with a detector response function (DRF) while optimizing the beam model. At convergence, the convolved profiles match the measured profiles, indicating the calculated profiles match the “true” beam profiles. To validate the approach, beam profiles of an Elekta LINAC were repeatedly collected with ICs of various volumes (CC04, CC13 and SNC 125) to obtain clinically acceptable beam models. The TPS-calculated profiles were convolved externally with the DRF of respective IC. The beam model parameters were reoptimized using Nelder-Mead method by forcing the convolved profiles to match the measured profiles. We evaluated three types of DRFs (Gaussian, Lorentzian, and parabolic) and the impact of kernel dependence on field geometry (depth and field size). The profiles calculated with beam models were compared with SNC EDGE diode-measured profiles. Results: The method was successfully implemented with Pinnacle Scripting and Matlab. The reoptimization converged in ∼10 minutes. For all tested ICs and DRFs, penumbra widths of the TPS-calculated profiles and diode-measured profiles were within 1.0 mm. Gaussian function had the best performance with mean penumbra width difference within 0.5 mm. The use of geometry dependent DRFs showed marginal improvement, reducing the penumbra width differences to less than 0.3 mm. Significant increase in IMRT QA passing rates was achieved with the optimized beam model. Conclusion: The proposed approach significantly improved the accuracy of the TPS beam model. Gaussian functions as the convolution kernel performed consistently better than Lorentzian and
Effectiveness of Psychological and Pharmacological Treatments for Nocturnal Enuresis.
Houts, Arthur C.; And Others
1994-01-01
Assesses overall effectiveness of psychological and pharmacological treatments, relative effectiveness of specific treatments, and moderators of treatment effectiveness for nocturnal enuretic children via quantitative integration of research. Findings confirm that more children benefit from psychological than from pharmacological interventions and…
Volokin, Den; ReLlez, Lark
2014-01-01
The presence of atmosphere can appreciably warm a planet’s surface above the temperature of an airless environment. Known as a natural Greenhouse Effect (GE), this near-surface Atmospheric Thermal Enhancement (ATE) as named herein is presently entirely attributed to the absorption of up-welling long-wave radiation by greenhouse gases. Often quoted as 33 K for Earth, GE is estimated as a difference between planet’s observed mean surface temperature and an effective radiating temperature calcul...
López-Soria, S; Sibila, M; Nofrarías, M; Calsamiglia, M; Manzanilla, E G; Ramírez-Mendoza, H; Mínguez, A; Serrano, J M; Marín, O; Joisel, F; Charreyre, C; Segalés, J
2014-12-01
Porcine circovirus type 2 (PCV2) is a ubiquitous virus that mainly affects nursery and fattening pigs causing systemic disease (PCV2-SD) or subclinical infection. A characteristic sign in both presentations is reduction of average daily weight gain (ADWG). The present study aimed to assess the relationship between PCV2 load in serum and ADWG from 3 (weaning) to 21 weeks of age (slaughter) (ADWG 3-21). Thus, three different boar lines were used to inseminate sows from two PCV2-SD affected farms. One or two pigs per sow were selected (60, 61 and 51 piglets from Pietrain, Pietrain×Large White and Duroc×Large White boar lines, respectively). Pigs were bled at 3, 9, 15 and 21 weeks of age and weighted at 3 and 21 weeks. Area under the curve of the viral load at all sampling times (AUCqPCR 3-21) was calculated for each animal according to standard and real time quantitative PCR results; this variable was categorized as "negative or low" (10(5.3)). Data regarding sex, PCV2 antibody titre at weaning and sow parity was also collected. A generalized linear model was performed, obtaining that paternal genetic line and AUCqPCR 3-21 were related to ADWG 3-21. ADWG 3-21 (mean±typical error) for "negative or low", "medium" and "high" AUCqPCR 3-21 was 672±9, 650±12 and 603±16 g/day, respectively, showing significant differences among them. This study describes different ADWG performances in 3 pig populations that suffered from different degrees of PCV2 viraemia. PMID:25448444
Monitoring the effects of wastewater treatment strategies.
de-la-Ossa-Carretero, J A; Del-Pilar-Ruso, Y; Giménez-Casalduero, F; Sánchez-Lizaso, J L
2016-02-01
Wastewater disposal in coastal waters causes widespread environmental problems. Secondary treatment is expected to reduce the adverse effects of insufficiently treated wastewater. The environmental impact of sewage disposal via 18 wastewater treatment plants was analysed using the benthic opportunistic polychaetes and amphipods (BOPA) index. In previous studies this index proved to be an effective tool for monitoring sewage pollution. The impact of these discharges was highly related to treatment level, which ranged from pre-treatment to biological, as well as to flow rates and outfall position. Locations affected by pre-treated wastewater showed environmental degradation, especially marked near outfalls with higher flow rates. At most locations, biologically treated wastewater did not cause a significant impact and an improvement in ecological integrity was detected after this secondary treatment had been implemented. The impact of discharge was highly related to chemical oxygen demand (COD), suspended solids and nutrient concentrations, which are all lower in biologically treated wastewater. A 'moderate' ecological status was observed not only near sewage outfalls with high wastewater flow rates (>1,500,000 m(3)/month) with a COD over 200 mg/l but also near those with lower flow rates but with a COD over 400 mg/l. To reduce the impact of sewage disposal, it is necessary to carry out adequate treatment, have site outfalls deep enough, and implement water recycling. PMID:26801153
Lee, Romeo B.; Baring, Rito V.; Sta. Maria, Madelene A.
2016-01-01
The study seeks to estimate gender variations in the direct effects of (a) number of organizational memberships, (b) number of social networking sites (SNS), and (c) grade-point average (GPA) on global social responsibility (GSR); and in the indirect effects of (a) and of (b) through (c) on GSR. Cross-sectional survey data were drawn from questionnaire interviews involving 3,173 Filipino university students. Based on a path model, the three factors were tested to determine their inter-relatio...
Effectiveness of psychopharmacology in Anorexia Nervosa treatment
Zadka Lukasz
2015-06-01
Full Text Available The eating disorder that generates the highest death rate is that of anorexia nervosa, and current treatment is a combination of equalization of somatic state and patient education. Moreover, psychical symptoms occurring in the course of anorexia nervosa are thought to have a crucial influence on the course of the disease. Hence, in medical literature, the effectiveness of psychotherapeutic interventions is also widely described. Still, the implementation of appropriate psychopharmacology is now considered an additional method of treatment, rather than a therapy of choice. Yet, in spite of many years of research, there are no absolute recommendations given, nor are instructions within the scope of psychopharmacological treatment proffered, although the selection of psychopharmacological items must respect both the patient’s psychic and somatic states. In recent years, the popularity of psychopharmacological treatment has increased; therefore, we feel that it is justified to present the latest scientific information in this respect.
De La Paz, Susan; Felton, Mark K.
2010-01-01
This study examined the effects of historical reasoning strategy instruction on 11th-grade students. Students learned historical inquiry strategies using 20th Century American history topics ranging from the Spanish-American war to the Gulf of Tonkin incident. In addition, students learned a pre-writing strategy for composing argumentative essays…
An investigation of scale effects in family substance abuse treatment programs
Lee A James
2010-01-01
Abstract This short report investigates scale effects in family substance abuse treatment programs. In Massachusetts, the family substance abuse treatment programs were much more costly than other adult residential treatment models. State officials were concerned that the "scale" or size of these programs (averaging just eight families) was too small to be economical. Although the sample size (just nine programs) was too small to permit reliable inference, the data clearly signalled the impor...
Timothy J. Halliday; Sally Kwak
2007-01-01
The potential influence of peers and social networks on individual outcomes is important to a variety of educational policy debates including school vouchers, special education, middle school grade configurations and tracking. Researchers usually address the identification problems associated with credibly estimating peer effects in these settings but often do not account for ad-hoc definitions of peer-groups. In this paper, we use extensive information on peer groups to demonstrate that accu...
W. J. Souza; K. M. C. Santos; Cruz, A A; E. Franceschi; C. Dariva; Santos, A. F.; Santana, C C
2015-01-01
AbstractWater-in-oil (W/O) emulsions are complex mixtures generally found in crude oil production in reservoirs and processing equipment. Sedimentation studies of water-oil emulsions enable the analysis of the fluid dynamic behavior concerning separation of this system composed of two immiscible liquids. Gravitational settling was evaluated in this article for a model emulsion system consisting of water and a Brazilian crude oil diluted in a clear mineral oil as organic phase. The effects of ...
The influence of end-effects upon gamma knife treatment
We investigated the influence of the end-effects upon practical gamma knife treatment. The subjects are 213 cases treated from June 1997 to June 1999. The values of the end-effects of 18, 14, 8, 4 mm diameter collimator helmets are +4.7, +4.2, +3.6, +3.5%, respectively. Those values are under an acceptable limit of ±5%. Total exposure time per patient is 75.0 minutes on the average and 13.3 shots are used on the average. This reflects well that many patients, about 70%, have brain metastases. The estimated actual end-effects for each patient is +0.9%, which is considered to be negligible when taking into account the usage rate of different collimators. This value will drop more in future as we need to prolong exposure time to deliver the same dose according to radioactive disintegration. We have to set the exposure time thinking over the end-effects at every shot. But it is necessary to cope with the present situation deliberately that bone correction and so on have not been done. The measurement of dose difference between 1 x 2 min and 2 x 1 min irradiation is one of the ways to obtain the end-effects in a short time and the results were almost the same as the ones by the least square method. (author)
The effect of average cycling current on total energy of lithium-ion batteries for electric vehicles
Barai, Anup; Uddin, Kotub; Widanalage, W. D.; McGordon, Andrew; Jennings, Paul
2016-01-01
Predicting the remaining range of a battery reliably, accurately and simply is imperative for effective power management of electrified vehicles and reducing driver anxiety resulting from perceived low driving range. Techniques for predicting the remaining range of an electric vehicle exist; in the best cases they are scaled by factors that account for expected energy losses due to driving style, environmental conditions and the use of on-board energy consuming devices such as air-conditioning. In this work, experimental results that establish the dependence of remaining electrical energy on the vehicle battery immediate cycling history are presented. A method to estimate the remaining energy given short-term cycling history is presented. This method differs from the traditional state of charge methods typically used in battery management systems by considering energy throughput more directly.
An investigation of scale effects in family substance abuse treatment programs.
Lee, A James
2010-01-01
This short report investigates scale effects in family substance abuse treatment programs. In Massachusetts, the family substance abuse treatment programs were much more costly than other adult residential treatment models. State officials were concerned that the "scale" or size of these programs (averaging just eight families) was too small to be economical. Although the sample size (just nine programs) was too small to permit reliable inference, the data clearly signalled the importance of "scale effects" in these family substance abuse treatment programs. To further investigate scale effects in family substance abuse treatment programs, data from the Center for Substance Abuse Treatment's (CSAT's) Residential Women and Children and Pregnant and Postpartum Women (RWC-PPW) Demonstration were re-analyzed, focusing on the relationship between cost per family-day and the estimated average family census. This analysis indicates strong economies of scale up until an average family census of about 14, and less apparent scale effects beyond that point. In consideration of these and other study findings, a multidisciplinary interagency team redesigned the Massachusetts' family treatment program model. The new programs are larger than the former family treatment programs, with each new program having capacity to treat 11 to 15 families depending on family makeup. PMID:20602764
An investigation of scale effects in family substance abuse treatment programs
Lee A James
2010-07-01
Full Text Available Abstract This short report investigates scale effects in family substance abuse treatment programs. In Massachusetts, the family substance abuse treatment programs were much more costly than other adult residential treatment models. State officials were concerned that the "scale" or size of these programs (averaging just eight families was too small to be economical. Although the sample size (just nine programs was too small to permit reliable inference, the data clearly signalled the importance of "scale effects" in these family substance abuse treatment programs. To further investigate scale effects in family substance abuse treatment programs, data from the Center for Substance Abuse Treatment's (CSAT's Residential Women and Children and Pregnant and Postpartum Women (RWC-PPW Demonstration were re-analyzed, focusing on the relationship between cost per family-day and the estimated average family census. This analysis indicates strong economies of scale up until an average family census of about 14, and less apparent scale effects beyond that point. In consideration of these and other study findings, a multidisciplinary interagency team redesigned the Massachusetts' family treatment program model. The new programs are larger than the former family treatment programs, with each new program having capacity to treat 11 to 15 families depending on family makeup.
HE Zhen-ming; AO Ying-fang; WANG Jian-quan; HU Yue-lin; YIN Yu
2010-01-01
Background Pectoralis major tendon rupture is a relatively rare injury leading to both functional and cosmetic deficiency. The peak torque of the pectoralis major is significantly decreased after conservational treatment of a total rupture. We suppose that surgical intervention is better choice.Methods We retrospectively evaluated 12 patients who were diagnosed with distal pectoralis major muscle rupture and underwent operation in our institute from 1993 to 2007. All patients were male with a mean age of 32 (19-54) years. In 4 patients, tendon reconstruction was accomplished by fixing the tendon to the humerus using sutures passed through predrilled humeral bone tunnels. In 8 patients, tendon reconstruction was accomplished by directly suturing the muscle to the tendon. All patients followed an accelerated rehabilitation protocol. Treatment results were evaluated according to the following criteria: (1) visual analogue pain scale, (2) isokinetic strength measurements, (3) range of motion of shoulder joint, (4) cosmetic result, and (5) postoperative sports activity performance. In this study, we aimed to describe our surgical technique of reconstruction of the rupture of pectoralis major muscle and to summarize the clinical results of the operative treatment.Results At the final follow-up examination (6.5 years postoperatively), only nine patients were available for evaluation. Three of them had excellent results, and five had good results, while one had poor results. Eight of the patients were able to return to their preinjury level of sporting activity. In summary, 89% of the patients achieved excellent or good results. Conclusion Surgical treatment by anatomic tendon repair and accelerated rehabilitation can make recovery of strength and function of the pectoralis major muscle.
Giovanni Bruno; Orietta Dessy
2014-01-01
We extend the univariate results in Wooldridge (2005) to multivariate probit models, proving the following. 1) Average partial effects (APEs) based on joint probabilities are consistently estimated by conventional multivariate probit models under general forms of conditionally independent latent heterogeneity (LH) as long as the only constraints beyond normalization, if any, are within-equation homogenous restrictions. The normalization of choice is not neutral to consistency in models with c...
Summers, A F; Weber, S P; Lardner, H A; Funston, R N
2014-06-01
Postweaning heifer development systems were evaluated at 2 locations in a 4-yr study for their effect on performance and subsequent adaptation to grazing corn residue as a pregnant heifer. In Exp. 1, heifers were blocked by BW and randomly assigned to graze winter range (WR) or graze winter range and corn residue (CR). In Exp. 2, heifers were assigned to graze winter range and corn residue (CR) or graze winter range and placed in a drylot (DL). Artificial insemination and natural mating were used at breeding on the basis of location. In Exp. 1, heifers developed on corn residue tended (P = 0.11) to have reduced ADG compared with WR heifers. Subsequently, BW at the end of the 82-d corn residue grazing period tended (P = 0.09) to be lower for CR compared with WR heifers. However, the proportion of heifers attaining puberty before the breeding season and pregnancy rates were similar (P ≥ 0.29) for CR and WR heifers. Developing heifers on winter range tended (P = 0.09) to reduce heifer development costs $36/pregnant heifer compared with CR heifers. In Exp. 2, DL heifers had greater (P heifers, resulting in greater (P heifers compared with CR heifers (355 vs. 322 ± 9 kg). At pregnancy diagnosis BW remained greater (P = 0.02) for DL compared with CR heifers (423 vs. 406 ± 7 kg). Corn-residue-developed heifers had increased (P = 0.03) AI conception rates compared with DL heifers (78% vs. 67% ± 6%). However, there was no difference (P ≥ 0.21) in percent pubertal before the breeding season or final pregnancy rates for CR and DL heifers. Developing heifers on corn residue reduced (P = 0.02) heifer development costs $38/pregnant heifer compared with DL-developed heifers. A subset of pregnant heifers from both experiments grazed corn residue fields in late gestation. As pregnant heifers grazing corn residue, WR heifers (Exp. 1) tended to have reduced ADG compared with CR heifers (0.34 vs. 0.43 ± 0.08 kg/d, P = 0.07). Furthermore, in Exp. 2 CR heifers had greater (0
Bouyer, Patricia; Markey, Nicolas; Randour, Mickael; Larsen, Kim G.; Laursen, Simon
2015-01-01
Two-player quantitative zero-sum games provide a natural framework to synthesize controllers with performance guarantees for reactive systems within an uncontrollable environment. Classical settings include mean-payoff games, where the objective is to optimize the long-run average gain per action, and energy games, where the system has to avoid running out of energy. We study average-energy games, where the goal is to optimize the long-run average of the accumulated energy. We show that this ...
Gas production in the Barueri Wastewater Treatment Plant digesters shows lower values than projected. This fact conducted to the hypothesis that there could be dead zones caused by homogenization deficiencies. In order to verify this hypothesis a full scale essay was conducted with Iodine - 131 as tracer. A Mutual Cooperation Agreement was signed between the Sao Paulo Basic Sanitation Company (SABESP) and the Nuclear and Energetic Research Institute (IPEN) to conduct these essays. The results showed that the active volume was almost 88% of the nominal capacity. (author)
Effectiveness of Acupuncture Treatment in Cervical Pain.
Norma Ríos García
2012-09-01
Full Text Available A study is performed, longitudinal, prospective, descriptive in patients who attended the consultation of The Health Center With Beds (CSCC of Torbeck, in the Southern Department of Haiti, in order to determine the effectiveness of acupuncture treatment in patients with cervical pain, in the period between January and June 2011. We studied a universe of 73 patients and a sample of 60 patients, from these persons 30 used drug therapy (Group B and 30 patients which used acupuncture (Group A. We note that in both groups, the females were the most affected, with a prevalence between 31 and 60. The main symptom for both groups was pain (100%. Patients who were administered the acupuncture successfully evolved between the second and fourth days of starting treatment and patients in group B between 5 and 6 days. Acupuncture is an effective therapy in the management of neck pain, with few adverse reactions of the patient and drug zero cost.
Female urinary incontinence: effective treatment strategies.
Castro, R A; Arruda, R M; Bortolini, M A T
2015-04-01
Urinary incontinence is a dysfunction that tremendously affects women's quality of life, involving social, emotional and economic aspects. Although various treatments for urinary incontinence have been described, it is important to know which of them are truly effective. This review seeks to determine the current available therapies for women with stress urinary incontinence and overactive bladder syndrome, based on the best scientific evidence. PMID:25307986
Effectiveness of psychopharmacology in Anorexia Nervosa treatment
Zadka Lukasz
2015-01-01
The eating disorder that generates the highest death rate is that of anorexia nervosa, and current treatment is a combination of equalization of somatic state and patient education. Moreover, psychical symptoms occurring in the course of anorexia nervosa are thought to have a crucial influence on the course of the disease. Hence, in medical literature, the effectiveness of psychotherapeutic interventions is also widely described. Still, the implementation of appropriate psychopharmacology is ...
Gramkow, Claus
In this article two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very offten the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...... natural approximations to the Riemannian metric, and that the subsequent corrections are inherient in the least squares estimation. Keywords: averaging rotations, Riemannian metric, matrix, quaternion...
Van Essen, H.
2004-01-01
This paper addresses the problem of the separation of rotational and internal motion. It introduces the concept of average angular velocity as the moment of inertia weighted average of particle angular velocities. It extends and elucidates the concept of Jellinek and Li (1989) of separation of the energy of overall rotation in an arbitrary (non-linear) $N$-particle system. It generalizes the so called Koenig's theorem on the two parts of the kinetic energy (center of mass plus internal) to th...
Fibich, Gadi; Gavious, Arieh; Solan, Eilon
2012-01-01
Typically, models with a heterogeneous property are considerably harder to analyze than the corresponding homogeneous models, in which the heterogeneous property is replaced with its average value. In this study we show that any outcome of a heterogeneous model that satisfies the two properties of differentiability and interchangibility is O(\\epsilon^2) equivalent to the outcome of the corresponding homogeneous model, where \\epsilon is the level of heterogeneity. We then use this averaging pr...
Gramkow, Claus
1999-01-01
In this article two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very offten the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...... natural approximations to the Riemannian metric, and that the subsequent corrections are inherient in the least squares estimation. Keywords: averaging rotations, Riemannian metric, matrix, quaternion...
Averaged extreme regression quantile
Jureckova, Jana
2015-01-01
Various events in the nature, economics and in other areas force us to combine the study of extremes with regression and other methods. A useful tool for reducing the role of nuisance regression, while we are interested in the shape or tails of the basic distribution, is provided by the averaged regression quantile and namely by the average extreme regression quantile. Both are weighted means of regression quantile components, with weights depending on the regressors. Our primary interest is ...
LIN Hong-rong; YANG Ai-xia; QIAN Sheng; LI Yue-hui
2004-01-01
In this paper, the effect of system and amplifier parameters on the performance of soliton transmission system using Phase Sensitive Amplifier (PSA) as in-line amplifier has been researched theoretically by computer simulation.Since in PSA soliton system the performance of average soliton regime is much better than that of dynamic soliton regime,in our simulation we only considered average soliton regime. Our simulation results show that although using PSA as inline amplifiers in soliton system can not only overcome Gordon-Haus restriction but also suppress solitons interaction,lengthen soliton stable transmission distance significantly, the system and amplifier parameters have to be chosen carefully in order to get a better system performance.
Psoriasis: characteristics, psychosocial effects and treatment options.
Ryan, Sheila
2012-02-01
Psoriasis is a complex chronic non-infectious inflammatory skin disease with a variety of different presentations. The classic presentation is of well-defined red plaques with silver scale. The characteristic scale makes the disorder highly visible and intrusive on the patient\\'s lifestyle. The visible nature of the disease ensures that psoriasis has both physical and psychosocial effects. In normal skin, epidermal cell reproduction and proliferation takes 28 days. In psoriasis this process is considerably accelerated to approximately 4 days, resulting in the deposit of immature cells on the skin. While the exact cause of this process is unknown, certain environmental and genetic factors are known to be triggers. Disease management depends on disease severity, psychosocial effects and the patient\\'s lifestyle. To effectively treat this disease the nurse must be skilled in psoriasis management, and in patient education and motivation. This article reviews the characteristics, aetiology, psychosocial effects and treatment strategies of psoriasis.
Identification of treatment effects on the treated with one-sided non-compliance
Frölich, Markus; Melly, Blaise
2008-01-01
Traditional instrumental variable estimators do not generally estimate effects for the treated population but for the unobserved population of compliers. They do identify effects for the treated when there is one-sided perfect non-compliance. However, this property is lost when covariates are included in the model. In this case, we show that the effects for the treated are still identified but require modified estimators. We consider both average and quantile treatment effects and allow the i...
Diagne, Aliou
2006-01-01
This paper shows that the observed sample adoption rate does not consistently estimate the population adoption rate even if the sample is random. It is proved that instead the sample adoption rate is a consistent estimate of the population joint exposure and adoption rate, which does not inform about adoption per se. Likewise, it is shown that a model of adoption with observed adoption outcome as dependent variable and where exposure to the technology is not observed and controlled for cannot...
Tina R Kilburn
Full Text Available Deficits in information processing may be a core deficit after fetal alcohol exposure. This study was designed to investigate the possible effects of weekly low to moderate maternal alcohol consumption and binge drinking episodes in early pregnancy on choice reaction time (CRT and information processing time (IPT in young children.Participants were sampled based on maternal alcohol consumption during pregnancy. At the age of 60-64 months, 1,333 children were administered a modified version of the Sternberg paradigm to assess CRT and IPT. In addition, a test of general intelligence (WPPSI-R was administered.Adjusted for a wide range of potential confounders, this study showed no significant effects of average weekly maternal alcohol consumption during pregnancy on CRT or IPT. There was, however, an indication of slower CRT associated with binge drinking episodes in gestational weeks 1-4.This study observed no significant effects of average weekly maternal alcohol consumption during pregnancy on CRT or IPT as assessed by the Sternberg paradigm. However, there were some indications of CRT being associated with binge drinking during very early pregnancy. Further large-scale studies are needed to investigate effects of different patterns of maternal alcohol consumption on basic cognitive processes in offspring.
PROBIOTIC: AS EFFECTIVE TREATMENT OF DISEASES
Arora Neha
2012-01-01
Full Text Available Probiotic are defined as live organisms, which confer benefits to the host. Their efficiency was demonstrated for the treatment of gastrointestinal disorders, respiratory infections, and allergic symptoms, but their use is mostly limited to bacterial and viral diseases. During the last decade, probiotic as means for the control of parasite infections were reported covering mainly intestinal diseases but also some nongut infections that are all of human and veterinary importance. In most cases, evidence for a beneficial effect was obtained by studies using animal models. In a few cases, cellular interactions between probiotic and pathogens or relevant host cells were also investigated using in vitro culture systems. WHO have given special guidelines for probiotic. Bifidobacteria have been studied for their efficacy in the prevention and treatment of a broad spectrum of animal and/or human gastrointestinal disorders, such as colonic transit disorders, intestinal infections, and colonic adenomas and cancer.
Essén, H
2003-01-01
This paper addresses the problem of the separation of rotational and internal motion. It introduces the concept of average angular velocity as the moment of inertia weighted average of particle angular velocities. It extends and elucidates the concept of Jellinek and Li (1989) of separation of the energy of overall rotation in an arbitrary (non-linear) $N$-particle system. It generalizes the so called Koenig's theorem on the two parts of the kinetic energy (center of mass plus internal) to three parts: center of mass, rotational, plus the remaining internal energy relative to an optimally translating and rotating frame.
Carrillo, Rafael E; Wiaux, Yves
2013-01-01
Recent developments in Carrillo et al. (2012) and Carrillo et al. (2013) introduced a novel regularization method for compressive imaging in the context of compressed sensing with coherent redundant dictionaries. The approach relies on the observation that natural images exhibit strong average sparsity over multiple coherent frames. The associated reconstruction algorithm, based on an analysis prior and a reweighted $\\ell_1$ scheme, is dubbed Sparsity Averaging Reweighted Analysis (SARA). We review these advances and extend associated simulations establishing the superiority of SARA to regularization methods based on sparsity in a single frame, for a generic spread spectrum acquisition and for a Fourier acquisition of particular interest in radio astronomy.
CNS effects following the treatment of malignancy
Rane, N., E-mail: rane@cantab.net [Department of Neuroradiology, The West Wing, John Radcliffe Hospital, Oxford Radcliffe NHS Trust, Oxford (United Kingdom); Quaghebeur, G. [Department of Neuroradiology, The West Wing, John Radcliffe Hospital, Oxford Radcliffe NHS Trust, Oxford (United Kingdom)
2012-01-15
Corporeal and central nervous system (CNS) axis chemotherapy and radiotherapy have long been used for the effective treatment and prophylaxis of CNS, body malignancies, and leukaemias. However, they are not without their problems. Following the proliferation of magnetic resonance neuroimaging in recent years it has become clear that the spectrum of toxicity that these therapies produce ranges from subclinical white matter changes to overt brain necrosis. The effects are both direct and indirect and via different pathological mechanisms. Chronic and progressive changes can be detected many years after the initial intervention. In addition to leucoencephalopathic changes, grey matter changes are now well described. Changes may be difficult to distinguish from tumour recurrence, though may be reversible and remediable, and are thus very important to differentiate. In this review toxic effects are classified and their imaging appearances discussed, with reference to specific syndromes.
基于平均能流密度的趋肤效应诠释%Study on the Skin Effect Based on the Average Energy Flow Density
刘细阳; 马伏花; 陈羡美
2014-01-01
The essence of the skin effect is a kind of propagation behavior of electromagnetic wave.The explanation about the skin effect in the existing teaching materials is only based on the skin depth.In this paper,through the analysis of the reflection wave and transmission wave formed when the electromagnetic wave is passing different media interface,the expressions of the electromagnetic field and the average energy flow density are given for two kinds of medium.According to different conductivity of the medium,the cal-culating formula of corresponding average energy flow density is derived,and the nature of the skin effect of the average energy flow density is explained.%趋肤效应的实质是一种电磁波的传播行为。一般研究仅从趋肤深度的角度理解趋肤效应。通过分析电磁波经过不同媒质界面时会形成的反射波和透射波，给出了两种媒质中的电磁场表达式及平均能流密度的表达式。根据媒质电导率的不同，推导出相应的平均能流密度的计算公式，从平均能流密度的角度，诠释了趋肤效应的本质。
Treatment conditions and biochemical processes influencing seed priming effectiveness
Giuseppe Di Girolamo
2012-05-01
Full Text Available A review of the scientific literature indicates osmotic priming (osmopriming as the principal method of seed priming and polyethylene glycol (PEG as the principal osmotic agent. An analysis of the available data across experiments carried out with different species under varying conditions showed an average 11% increase in percent germination and 36% shorter mean germination time (MGT in primed vs. unprimed seeds. Moreover, in primed seeds MGT was less dependent on temperature, which is consistent with the effects expected from the treatment. Priming effects are mainly influenced by osmotic potential, temperature and time; major biochemical processes (repair of damaged DNA and RNA, preparation for cell division and increased antioxidant activity are involved in treatment effects to an extent which is not fully ascertained in literature. A reduction of seed storage life is the major disadvantage of priming and the principal constraint to its diffusion, since dehydration to the initial moisture (drying-back is needed to allow seed storage. Seed behaviour during drying-back, the role of the raffinose family oligosaccharides in cell membrane integrity and the expression of antioxidant enzymes in germinating seeds need to be further elucidated in a sufficient number of species, to promote a more reliable use of this technique.
Gramkow, Claus
2001-01-01
In this paper two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very often the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong to...
For the assessment of plutonium in the lungs, several corrections must be made to X-ray counting data obtained from direct measurement of a person inhaled plutonium aerosol. X/α ratio varying with isotopic composition is one of the important correction factors required in interpretation of the counting data. This paper describes a method of determination of X/α ratio of plutonium, using X-ray - alpha coincidence counter consisted of a proportional counter and a thin NaI-detector, and also describes an empirical method for estimating average effective energy of plutonium which has different isotopic composition. (author)
Effect of pioglitazone treatment on behavioral symptoms in autistic children
Edelson Stephen M
2007-01-01
Full Text Available Abstract Introduction Autism is complex neuro-developmental disorder which has a symptomatic diagnosis in patients characterized by disorders in language/communication, behavior, and social interactions. The exact causes for autism are largely unknown, but is has been speculated that immune and inflammatory responses, particularly those of Th2 type, may be involved. Thiazolidinediones (TZDs are agonists of the peroxisome proliferator activated receptor gamma (PPARγ, a nuclear hormone receptor which modulates insulin sensitivity, and have been shown to induce apoptosis in activated T-lymphocytes and exert anti-inflammatory effects in glial cells. The TZD pioglitazone (Actos is an FDA-approved PPARγ agonist used to treat type 2 diabetes, with a good safety profile, currently being tested in clinical trials of other neurological diseases including AD and MS. We therefore tested the safety and therapeutic potential of oral pioglitazone in a small cohort of children with diagnosed autism. Case description The rationale and risks of taking pioglitazone were explained to the parents, consent was obtained, and treatment was initiated at either 30 or 60 mg per day p.o. A total of 25 children (average age 7.9 ± 0.7 year old were enrolled. Safety was assessed by measurements of metabolic profiles and blood pressure; effects on behavioral symptoms were assessed by the Aberrant Behavior Checklist (ABC, which measures hyperactivity, inappropriate speech, irritability, lethargy, and stereotypy, done at baseline and after 3–4 months of treatment. Discussion and evaluation In a small cohort of autistic children, daily treatment with 30 or 60 mg p.o. pioglitazone for 3–4 months induced apparent clinical improvement without adverse events. There were no adverse effects noted and behavioral measurements revealed a significant decrease in 4 out of 5 subcategories (irritability, lethargy, stereotypy, and hyperactivity. Improved behaviors were inversely
Romeo B. Lee
2016-02-01
Full Text Available The study seeks to estimate gender variations in the direct effects of (a number of organizational memberships, (b number of social networking sites (SNS, and (c grade-point average (GPA on global social responsibility (GSR; and in the indirect effects of (a and of (b through (c on GSR. Cross-sectional survey data were drawn from questionnaire interviews involving 3,173 Filipino university students. Based on a path model, the three factors were tested to determine their inter-relationships and their relationships with GSR. The direct and total effects of the exogenous factors on the dependent variable are statistically significantly robust. The indirect effects of organizational memberships on GSR through GPA are also statistically significant, but the indirect effects of SNS on GSR through GPA are marginal. Men and women significantly differ only in terms of the total effects of their organizational memberships on GSR. The lack of broad gender variations in the effects of SNS, organizational memberships and GPA on GSR may be linked to the relatively homogenous characteristics and experiences of the university students interviewed. There is a need for more path models to better understand the predictors of GSR in local students.
Lee, Romeo B; Baring, Rito V; Sta Maria, Madelene A
2016-02-01
The study seeks to estimate gender variations in the direct effects of (a) number of organizational memberships, (b) number of social networking sites (SNS), and (c) grade-point average (GPA) on global social responsibility (GSR); and in the indirect effects of (a) and of (b) through (c) on GSR. Cross-sectional survey data were drawn from questionnaire interviews involving 3,173 Filipino university students. Based on a path model, the three factors were tested to determine their inter-relationships and their relationships with GSR. The direct and total effects of the exogenous factors on the dependent variable are statistically significantly robust. The indirect effects of organizational memberships on GSR through GPA are also statistically significant, but the indirect effects of SNS on GSR through GPA are marginal. Men and women significantly differ only in terms of the total effects of their organizational memberships on GSR. The lack of broad gender variations in the effects of SNS, organizational memberships and GPA on GSR may be linked to the relatively homogenous characteristics and experiences of the university students interviewed. There is a need for more path models to better understand the predictors of GSR in local students. PMID:27247700
Lee, Romeo B.; Baring, Rito V.; Sta. Maria, Madelene A.
2016-01-01
The study seeks to estimate gender variations in the direct effects of (a) number of organizational memberships, (b) number of social networking sites (SNS), and (c) grade-point average (GPA) on global social responsibility (GSR); and in the indirect effects of (a) and of (b) through (c) on GSR. Cross-sectional survey data were drawn from questionnaire interviews involving 3,173 Filipino university students. Based on a path model, the three factors were tested to determine their inter-relationships and their relationships with GSR. The direct and total effects of the exogenous factors on the dependent variable are statistically significantly robust. The indirect effects of organizational memberships on GSR through GPA are also statistically significant, but the indirect effects of SNS on GSR through GPA are marginal. Men and women significantly differ only in terms of the total effects of their organizational memberships on GSR. The lack of broad gender variations in the effects of SNS, organizational memberships and GPA on GSR may be linked to the relatively homogenous characteristics and experiences of the university students interviewed. There is a need for more path models to better understand the predictors of GSR in local students.
Covariant approximation averaging
Shintani, Eigo; Blum, Thomas; Izubuchi, Taku; Jung, Chulwoo; Lehner, Christoph
2014-01-01
We present a new class of statistical error reduction techniques for Monte-Carlo simulations. Using covariant symmetries, we show that correlation functions can be constructed from inexpensive approximations without introducing any systematic bias in the final result. We introduce a new class of covariant approximation averaging techniques, known as all-mode averaging (AMA), in which the approximation takes account of contributions of all eigenmodes through the inverse of the Dirac operator computed from the conjugate gradient method with a relaxed stopping condition. In this paper we compare the performance and computational cost of our new method with traditional methods using correlation functions and masses of the pion, nucleon, and vector meson in $N_f=2+1$ lattice QCD using domain-wall fermions. This comparison indicates that AMA significantly reduces statistical errors in Monte-Carlo calculations over conventional methods for the same cost.
Fibich, Gadi; Gavious, Arieh; Solan, Eilon
2012-01-01
Typically, models with a heterogeneous property are considerably harder to analyze than the corresponding homogeneous models, in which the heterogeneous property is replaced with its average value. In this study we show that any outcome of a heterogeneous model that satisfies the two properties of \\emph{differentiability} and \\emph{interchangibility}, is $O(\\epsilon^2)$ equivalent to the outcome of the corresponding homogeneous model, where $\\epsilon$ is the level of heterogeneity. We then us...
Background: Dual-source CT coronary angiography (CTCA) has been used to detect coronary artery disease; however, the factors with potential to affect its diagnostic accuracy remain to be defined. Purpose: To prospectively evaluate the accuracy of dual-source CTCA in diagnosing coronary artery stenosis according to conventional coronary angiography (CAG), and the effect of average heart rate, heart rate variability, and calcium score on the accuracy of CTCA. Material and Methods: A total of 113 patients underwent both dual-source CTCA and CAG. The results were used to evaluate the findings in dual-source CTCA to assess the accuracy in the diagnosis of =50% (significant stenosis) and >75% (severe stenosis) of coronary artery according to those by CAG. Patients were divided into subgroups according to their heart rate (HR), HR variability (HRV), and calcium score, and the accuracy of CTCA was further evaluated. The chi-square test was used to analyze the difference in sensitivity and specificity for the detection of =50% and >75% coronary stenosis among subgroups. The generalized estimation equation method was used in per-vessel analysis to adjust for within-patient correlation. Results: In all, 113 patients had 338 vessels and 1661 segments evaluated by CAG. Dual-source CTCA displayed 1527 segments (91.9%). Among them, 1468 segments (calcium score by CAG score 1, n=1018; score 2, n=270; score 3, n=180) were assessable in CTCA. On a per-patient analysis, the sensitivity and specificity of CTCA were 93.9% and 93.5% for significant stenosis and 86.9% and 98.1% for severe stenosis. On a per-vessel basis, the sensitivity and specificity were 90.2% and 97.1% for significant and 83.3% and 98.1% for severe stenosis. On a per-segment analysis, the sensitivity and specificity were 90.2% and 97.1% for significant and 83.3% and 98.1% for severe stenosis. Average HR had no effect on the sensitivity and specificity of CTCA (P>0.05); whereas HRV and calcium score had some effect on
Vocal attractiveness increases by averaging.
Bruckert, Laetitia; Bestelmeyer, Patricia; Latinus, Marianne; Rouger, Julien; Charest, Ian; Rousselet, Guillaume A; Kawahara, Hideki; Belin, Pascal
2010-01-26
Vocal attractiveness has a profound influence on listeners-a bias known as the "what sounds beautiful is good" vocal attractiveness stereotype [1]-with tangible impact on a voice owner's success at mating, job applications, and/or elections. The prevailing view holds that attractive voices are those that signal desirable attributes in a potential mate [2-4]-e.g., lower pitch in male voices. However, this account does not explain our preferences in more general social contexts in which voices of both genders are evaluated. Here we show that averaging voices via auditory morphing [5] results in more attractive voices, irrespective of the speaker's or listener's gender. Moreover, we show that this phenomenon is largely explained by two independent by-products of averaging: a smoother voice texture (reduced aperiodicities) and a greater similarity in pitch and timbre with the average of all voices (reduced "distance to mean"). These results provide the first evidence for a phenomenon of vocal attractiveness increases by averaging, analogous to a well-established effect of facial averaging [6, 7]. They highlight prototype-based coding [8] as a central feature of voice perception, emphasizing the similarity in the mechanisms of face and voice perception. PMID:20129047
Robust Averaging Level Control
Rosander, Peter; Isaksson, Alf; Löfberg, Johan; Forsman, Krister
2011-01-01
Frequent inlet ﬂow changes typically cause problems for averaging level controllers. For a frequently changing inlet ﬂow the upsets do not occur when the system is in steady state and the tank level at its set-point. For this reason the tuning of the level controller gets quite complicated, since not only the size of the upsets but also the time in between them relative to the hold up of the tank have to be considered. One way to obtain optimal ﬂow ﬁltering while directly accounting for futur...
Ding, Peng; Dasgupta, Tirthankar
2016-01-01
Fisher randomization tests for Neyman's null hypothesis of no average treatment effects are considered in a finite population setting associated with completely randomized experiments with more than two treatments. The consequences of using the F statistic to conduct such a test are examined both theoretically and computationally, and it is argued that under treatment effect heterogeneity, use of the F statistic can severely inflate the type I error of the Fisher randomization test. An altern...
[Effectiveness of dietetic treatment in nephrotic syndrome].
Calleja Fernández, A; López Gómez, J J; Vidal Casariego, A; Cano Rodríguez, I; Ballesteros Pomar, M D
2009-01-01
We present the case of a male patient suffering from a primary amyloidosis and a nephrotic syndrome who came to dietotherapy clinic. In the first visit we made a nutritional record including an anthropometric evaluation, body composition, biochemistry, and food intake. The patient had an excess of body water, proteinuria, low plasma protein, albumin, prealbumin and HDL cholesterol levels, and high concentrations of total cholesterol, LDL and triglycerides. The consumption of protein and sodium was higher than the recommendation. An individualized diet was made. Six months later, his weight and the excess of body water decreased, but the fat free mass remained unchanged. The levels of albumin and prealbumin increased, the proteinuria decreased. Total cholesterol, LDL and triglycerides decreased until normal levels. Dietetary treatment in nephrotic syndrome is effective to decrease proteinuria, improve cholesterol and triglycerides levels, and to prevent malnutrition. PMID:20049380
Negative Average Preference Utilitarianism
Roger Chao
2012-03-01
Full Text Available For many philosophers working in the area of Population Ethics, it seems that either they have to confront the Repugnant Conclusion (where they are forced to the conclusion of creating massive amounts of lives barely worth living, or they have to confront the Non-Identity Problem (where no one is seemingly harmed as their existence is dependent on the “harmful” event that took place. To them it seems there is no escape, they either have to face one problem or the other. However, there is a way around this, allowing us to escape the Repugnant Conclusion, by using what I will call Negative Average Preference Utilitarianism (NAPU – which though similar to anti-frustrationism, has some important differences in practice. Current “positive” forms of utilitarianism have struggled to deal with the Repugnant Conclusion, as their theory actually entails this conclusion; however, it seems that a form of Negative Average Preference Utilitarianism (NAPU easily escapes this dilemma (it never even arises within it.
Jensen, Dan B.; Toft, Nils; Cornou, Cécile
2014-01-01
Pigs are known to be particularly sensitive to heat and cold. If the temperature becomes too low, the pigs will grow less efficiently and be more susceptible to diseases such as pneumonia. If the temperature is too high, the pigs will tend to foul the pen, leading to additional risks of infection....... Furthermore, unpublished data show that the temperature within a single section of grower/finisher pigs can vary considerably from pen to pen, and previous studies have shown that pigs can be significantly affected by wind, even when not directly exposed to it. To address this latter concern, some pig...... of the effects of wind shielding, linear mixed models were fitted to describe the average daily weight gain and feed conversion rate of 1271 groups (14 individuals per group) of purebred Duroc, Yorkshire and Danish Landrace boars, as a function of shielding (yes/no), insert season (winter, spring...
Gómez-Rocha, M.; Hilger, T.; Krassnigg, A.
2016-04-01
We extend earlier investigations of heavy-light pseudoscalar mesons to the vector case, using a simple model in the context of the Dyson-Schwinger-Bethe-Salpeter approach. We investigate the effects of a dressed quark-gluon vertex in a systematic fashion and illustrate and attempt to quantify corrections beyond the phenomenologically very useful and successful rainbow-ladder truncation. In particular we investigate the dressed quark-photon vertex in such a setup and make a prediction for the experimentally as yet unknown mass of the Bc* , which we obtain at 6.334 GeV well in line with predictions from other approaches. Furthermore, we combine a comprehensive set of results from the theoretical literature. The theoretical average for the mass of the Bc* meson is 6.336 ±0.002 GeV .
Average nuclear surface properties
The definition of the nuclear surface energy is discussed for semi-infinite matter. This definition is extended also for the case that there is a neutron gas instead of vacuum on the one side of the plane surface. The calculations were performed with the Thomas-Fermi Model of Syler and Blanchard. The parameters of the interaction of this model were determined by a least squares fit to experimental masses. The quality of this fit is discussed with respect to nuclear masses and density distributions. The average surface properties were calculated for different particle asymmetry of the nucleon-matter ranging from symmetry beyond the neutron-drip line until the system no longer can maintain the surface boundary and becomes homogeneous. The results of the calculations are incorporated in the nuclear Droplet Model which then was fitted to experimental masses. (orig.)
Effective Treatments of Atrophic Acne Scars
Gozali, Maya Valeska; ZHOU, BINGRONG
2015-01-01
Atrophic scarring is often an unfortunate and permanent complication of acne vulgaris. It has high prevalence, significant impact on quality of life, and therapeutic challenge for dermatologists. The treatment of atrophic acne scars varies depending on the types of acne scars and the limitations of the treatment modalities in their ability to improve scars. Therefore, many options are available for the treatment of acne scarring, including chemical peeling, dermabrasion, laser treatment, punc...
Alonso, J L; Clemente-Gallardo, J; Echenique, P; Mazo, J J; Polo, V; Rubio, A; Zueco, D
2012-01-01
At non-zero temperature and when a system has low-lying excited electronic states, the ground-state Born--Oppenheimer approximation breaks down and the low-lying electronic states are involved in any chemical process. In this work, we use a temperature-dependent effective potential for the nuclei which can accomodate the influence of an arbitrary number of electronic states in a simple way, while at the same time producing the correct Boltzmann equibrium distribution for the electronic part. With the help of this effective potential, we show that thermally-activated low-lying electronic states can have a significant effect in molecular properties for which electronic excitations are oftentimes ignored. We study the thermal expansion of the Manganese dimer, Mn$_2$, where we find that the average bond length experiences a change larger than the present experimental accuracy upon the inclusion of the excited states into the picture. We also show that, when these states are taken into account, reaction rate const...
Effect of Heat Treatment on the Microstructure and Corrosion Resistance of Cu-Zn Alloy
Xu Tao; Zhang Hailong; Xiao Nianxin; Zhao Xiangling
2007-01-01
The microstructure of Cu-Zn alloy with different heat treatment conditions in 3.5% NaCl + NH3 solution were observed, and the average corrosion rates and electrochemical data of Cu-Zn alloy were measured, as well as the effect of heat treatment on microstructure and corrosion resistance of Cu-Zn alloy was analyzed. The results show that the microstructure of Cu-Zn alloy has been changed due to the heat treatment. As a results, the better corrosion resistance can be obtained for the Cu-Zn alloy quenched from 900℃ for 0.5h followed by tempered at 100℃ for 2h.
Instrumental variable estimation of treatment effects for duration outcomes
G.E. Bijwaard (Govert)
2007-01-01
textabstractIn this article we propose and implement an instrumental variable estimation procedure to obtain treatment effects on duration outcomes. The method can handle the typical complications that arise with duration data of time-varying treatment and censoring. The treatment effect we defi
Effects of radiation treatment on foodstuffs
The purpose of this study is to discuss and compile methods and results of irradiation experiments carried out on 54 plant and animal foodstuffs in order to obtain a survey on chemical changes, in particular as regards the reduction of nutritional value and savoriness of irradiated foodstuffs. According to this task, microbiological aspects as well as an interpretation of the experimental results as to the physiology of nutrition and toxicology were not included. The results published by the authors of the original papers were compiled in a kind of dictionary which contains all relevant information such as radiation sources, irradiation conditions, investigation methods, results of chemical or organoleptical changes etc. The most important results were summarized in tables and can be found at the end of this study. Because of the abundance of existing literature the series 'Effects of radiation treatment on foodstuffs' will be continued in Part IV, and the final discussion of the results will be published separately after further data have been included. (orig.)
The Effect of Minimum Wage on Average Wage and Employment%最低工资对中国就业和工资水平的影响
马双; 张劼; 朱喜
2012-01-01
本文以1998--2007年全国各市（地区、自治州、盟）最低工资标准随时间变化的外生差异来识别最低工资上涨与企业平均工资、企业雇佣人数的关系。利用1998—2007年规模以上制造业企业报表数据进行的分析显示，最低工资每上涨10％，制造业企业平均工资将整体上涨0．4％-0．5％。借助2006--2007年福建省最低工资上涨的“准自然实验”本文也证实了该结论。对于不同行业、不同入均资本水平的企业，最低工资上涨的影响也存在异质性。最低工资将更多地增加劳动密集型或人均资本较低企业的平均工资。研究还发现，最低工资每增加10％，制造业企业雇佣人数将显著减少0．6％左右。政府在制定最低工资时应权衡其在收入分配上的积极效果以及其对就业的负面影响。%This paper evaluates the relationship among minimum wage, average wage and employment in Chinese manufacturing firms based on the exogenous variation of city-level minimum wages from 1998--2007. It is found that if the minimum wages increase by 10% , then the average wages in firms would pick up by 0.4% --0.5% , though there are some heterogeneity in the effect of minimum wage on various firms in different industries and asset per capita levels. The minimum wage policy would contribute more to the average wages hikes of labor intensive firms or firms with lower asset per capita than to other firms. With regard to the employment, it is shown that every raise of minimum wage by 10% would lead to significant employment loss by 0. 6% or so. The policy makers should balance the positive effect of minimum wage on the income distribution and its negative effect on the employment as far as the labor regulation is concerned.
Nilotinib Effective and Safe in Initial Treatment of CML
Preliminary results from a phase III trial testing nilotinib (Tasigna) against imatinib mesylate (Gleevec) as first-line treatment for chronic-phase chronic myelogenous leukemia (CML) indicate that nilotinib is effective and safe as initial treatment for
The treatment of resonance interference effects in the subgroup method
Research highlights: → In this paper, we propose to first remedy the inaccurate treatment of the interference effect between resonance isotopes in conventional subgroup method. → In our work we use group averaged cross section instead of resonance integrals in the objective function for generating subgroup weights. This is much more effective since group average cross sections are the parameters which will be used in transport calculation. We have shown that the subgroup group weights generated with this method improves the accuracy of the resonance integration. → We solved the least squares optimization problem with the penalty method for constraints. The Krylov subspace method, CGNR, was found to be very efficient method for solving this type of optimization problem. → In addition to U-238, which was used as resonance isotope in previous work on lambda factors, U-235 was also treated as a resonance isotope in the lambda calculation developed here. This improves the accuracy of the subgroup method since we are able to provide lambdas for the groups in which U-238 has no significant resonance. - Abstract: This paper describes the development of a method to treat resonance interference effects within the framework of the subgroup method. The new procedure provides for the treatment of multiple resonance absorbers in which the subgroup weights are determined using a least squares technique and based on the cross sections generated from a mixture of multiple resonance isotopes and a suitably wide range of background cross sections. The method was implemented in the Method of Characteristics code DeCART and validated using MCNP. In order to implement the new method, the NJOY code was used for the calculation of neutron spectra and resonance parameters in for each representative LWR mixture. The resonance parameters, lambda, of the scattering isotopes are computed not just with U-238 as the resonance isotope as in previous applications of the subgroup method
The treatment of resonance interference effects in the subgroup method
Gao Zhenjia [Purdue University, West Lafayette, IN (United States); Xu Yunlin [University of Michigan, Ann Arbor, MI (United States); Downar, Thomas J., E-mail: downar@umich.edu [University of Michigan, Ann Arbor, MI (United States)
2011-05-15
Research highlights: > In this paper, we propose to first remedy the inaccurate treatment of the interference effect between resonance isotopes in conventional subgroup method. > In our work we use group averaged cross section instead of resonance integrals in the objective function for generating subgroup weights. This is much more effective since group average cross sections are the parameters which will be used in transport calculation. We have shown that the subgroup group weights generated with this method improves the accuracy of the resonance integration. > We solved the least squares optimization problem with the penalty method for constraints. The Krylov subspace method, CGNR, was found to be very efficient method for solving this type of optimization problem. > In addition to U-238, which was used as resonance isotope in previous work on lambda factors, U-235 was also treated as a resonance isotope in the lambda calculation developed here. This improves the accuracy of the subgroup method since we are able to provide lambdas for the groups in which U-238 has no significant resonance. - Abstract: This paper describes the development of a method to treat resonance interference effects within the framework of the subgroup method. The new procedure provides for the treatment of multiple resonance absorbers in which the subgroup weights are determined using a least squares technique and based on the cross sections generated from a mixture of multiple resonance isotopes and a suitably wide range of background cross sections. The method was implemented in the Method of Characteristics code DeCART and validated using MCNP. In order to implement the new method, the NJOY code was used for the calculation of neutron spectra and resonance parameters in for each representative LWR mixture. The resonance parameters, lambda, of the scattering isotopes are computed not just with U-238 as the resonance isotope as in previous applications of the subgroup method, but also
Posttraumatic stress disorder: The development of effective psychological treatments
Ehlers, Anke; Clark, David M.
2008-01-01
Posttraumatic stress disorder (PTSD) has only relatively recently been introduced into the diagnostic classification of mental disorders. Building on advances in the treatment of other anxiety disorders, a range of effective psychological treatments for PTSD has been developed. The most effective of these treatments focus on the patient’s memory for the traumatic event and its meaning. This paper briefly reviews the currently available evidence for these treatments. It then illustrates the pr...
The present study quantified the volume-averaged in situ electric field in nerve tissues of anatomically based numeric Japanese male and female models for exposure to extremely low-frequency electric and magnetic fields. A quasi-static finite-difference time-domain method was applied to analyze this problem. The motivation of our investigation is that the dependence of the electric field induced in nerve tissue on the averaging volume/distance is not clear, while a cubical volume of 5 x 5 x 5 mm3 or a straight-line segment of 5 mm is suggested in some documents. The influence of non-nerve tissue surrounding nerve tissue is also discussed by considering three algorithms for calculating the averaged in situ electric field in nerve tissue. The computational results obtained herein reveal that the volume-averaged electric field in the nerve tissue decreases with the averaging volume. In addition, the 99th percentile value of the volume-averaged in situ electric field in nerve tissue is more stable than that of the maximal value for different averaging volume. When including non-nerve tissue surrounding nerve tissue in the averaging volume, the resultant in situ electric fields were not so dependent on the averaging volume as compared to the case excluding non-nerve tissue. In situ electric fields averaged over a distance of 5 mm were comparable or larger than that for a 5 x 5 x 5 mm3 cube depending on the algorithm, nerve tissue considered and exposure scenarios. (note)
Nagengast, Benjamin; Marsh, Herbert W.
2011-01-01
Research on the relation between students' achievement (ACH) and their academic self-concept (ASC) has consistently shown a Big-Fish-Little-Pond-Effect (BFLPE); ASC is positively affected by individual ACH, but negatively affected by school-average ACH. Surprisingly, however, there are few good UK studies of the BFLPE and few anywhere in the world…
K. Chandrashekara
2016-01-01
Full Text Available Eight medicinal plants and soil samples from the Malnad area of Karnataka in South India (N 13°29′35.4″; E 75°18′02.4″ were analysed for activity concentrations of natural and artificial radionuclides using HPGe gamma spectrometry. The average annual committed effective dose (AACED due to the ingestion of radionuclides from medicinal plants were also estimated. The activity concentrations of 226Ra, 210Pb, 232Th, and 40K were found to vary in the range of 32.27–60.12 Bqkg−1, 56.09–160.56 Bqkg−1, 49.61–98.46 Bqkg−1, and 241.57–712.85 Bqkg−1, respectively, in the soil samples and 2.66–11.27 Bqkg−1, BDL to 87.03 Bqkg−1, 2.42–8.72 Bqkg−1, and 93.79–6831.40 Bqkg−1, respectively, in the medicinal plants corresponding to the soil samples. The activity concentration of artificially produced radionuclide 137Cs was BDL to 12.34 Bqkg−1 in the soil and it was below detectable level (BDL in all the plant samples. The soil to plant transfer factors (TF varied from 0.07 to 0.27, BDL to 0.80, 0.04 to 0.13 and 0.17 to 23.80, respectively, for 226Ra, 210Pb, 232Th, and 40K. The AACED due to the ingestion of radionuclides from the medicinal plants varied from 0.0075 to 0.1067 mSvy−1. The AACED values reported in this study are much below the world average value of 0.30 mSvy−1 for an individual. This indicates that there is no radiological health risk in using these plants for medicinal purposes. This study may also contribute data on local medicinal plants to formulate regulations related to radiological healthcare.
Steroid Treatments Equally Effective Against Sudden Deafness
... Human Services Search the NIH Website NIH Employee Intranet Staff Directory En Español Site Menu Home Health ... with sudden deafness should discuss the risks and benefits of both treatments with their doctor.” Related Links ...
Effective dose evaluation for BNCT treatment in the epithermal neutron beam at THOR
This paper aims to evaluate the effective dose as well as equivalent doses of several organs of an adult hermaphrodite mathematical phantom according to the definition of ICRP Publication 60 for BNCT treatments of brain tumors in the epithermal neutron beam at THOR. The MCNP5 Monte Carlo code was used for the calculation of the average absorbed dose of each organ. The effective doses for a typical brain tumor treatment with a tumor treatment dose of 20 Gy-eq were evaluated to be 0.59 and 0.35 Sv for the LLAT and TOP irradiation geometries, respectively. In addition to the stochastic effect, it was found that it is also likely to produce deterministic effects, such as cataracts and depression of haematopoiesis.
Chen, Chieh-Li; Ishikawa, Hiroshi; Wollstein, Gadi; Bilonick, Richard A.; Kagemann, Larry; Schuman, Joel S.
2016-01-01
Purpose Developing a novel image enhancement method so that nonframe-averaged optical coherence tomography (OCT) images become comparable to active eye-tracking frame-averaged OCT images. Methods Twenty-one eyes of 21 healthy volunteers were scanned with noneye-tracking nonframe-averaged OCT device and active eye-tracking frame-averaged OCT device. Virtual averaging was applied to nonframe-averaged images with voxel resampling and adding amplitude deviation with 15-time repetitions. Signal-to...
Early onset of treatment effects with oral risperidone
Naber Dieter
2007-01-01
Full Text Available Abstract Background The dogma of a delayed onset of antipsychotic treatment effects has been maintained over the past decades. However, recent studies have challenged this concept. We therefore performed an analysis of the onset of antipsychotic treatment effects in a sample of acutely decompensated patients with schizophrenia. Methods In this observational study, 48 inpatients with acutely decompensated schizophrenia were offered antipsychotic treatment with oral risperidone. PANSS-ratings were obtained on day 0, day 1, day 3, day 7 and day 14. Results Significant effects of treatment were already present on day 1 and continued throughout the study. The PANSS positive subscore and the PANSS total score improved significantly more than the PANSS negative subscore. Conclusion Our results are consistent with the growing number of studies suggesting an early onset of antipsychotic treatment effects. However, non-pharmacological effects of treatment also need to be taken into consideration.
Baluev, V. V.; Rzaev, A. I.
1992-08-01
Experimental results on the average heat transfer from a cylinder in a liquid-penetrated granular bed are presented and the dependence of the heat transfer rate on the particle size in the bed is found.
Hah, Chunill
2011-01-01
The current paper reports on an investigation of steady and unsteady flow effects of circumferential grooves casing treatment in a transonic compressor rotor. Circumferential grooves casing treatment is used mainly to increase stall margin in axial compressors with a relatively small decrease in aerodynamic efficiency. It is widely believed that flow mechanisms of circumferential grooves casing treatment near stall conditions are not yet well understood even though this treatment has been used widely in real engines. Numerical analysis based on steady Reynolds-averaged Navier-Stokes (RANS) has been the primary tool used to understand flow mechanism for circumferential grooves casing treatment. Although steady RANS explains some flow effects of circumferential grooves casing treatment, it does not calculate all the measured changes in the compressor characteristics. Therefore, design optimization of circumferential grooves with steady RANS has not been very successful. As a compressor operates toward the stall condition, the flow field becomes transient. Major sources of self-generated flow unsteadiness are shock oscillation and interaction between the passage shock and the tip leakage vortex. In the present paper, an unsteady Reynolds-averaged Navier-Stokes (URANS) approach is applied to study the effects of circumferential grooves in a transonic compressor. The results from URANS are compared with the results from RANS and measured data. The current investigation shows that there are significant unsteady flow effects on the performance of the circumferential grooves casing treatment. For the currently investigated rotor, the unsteady effects are of the same magnitude as the steady effects in terms of extending the compressor stall margin.
Cost Effectiveness of Treatments for Amyotrophic Lateral Sclerosis: A Review of the Literature
Gary Ginsberg; Serena Lowe
2002-01-01
Amyotrophic lateral sclerosis (ALS) is a difficult to diagnose, fatal, progressive degenerative disease with an average survival time of 2 to 5 years. Percutaneous endoscopic gastrotomy (PEG) and bi-level intermittent positive pressure (BIPAP) ventilation may be the major interventions leading to longer survival of patients with ALS. Riluzole has been shown to have modest effects on survival (as opposed to functional) gains and is currently the only drug approved for the treatment of ALS. The...
Assessment of the effects of CT dose in averaged x-ray CT images of a dose-sensitive polymer gel
The signal-to-noise ratio achievable in x-ray computed tomography (CT) images of polymer gels can be increased by averaging over multiple scans of each sample. However, repeated scanning delivers a small additional dose to the gel which may compromise the accuracy of the dose measurement. In this study, a NIPAM-based polymer gel was irradiated and then CT scanned 25 times, with the resulting data used to derive an averaged image and a ''zero-scan'' image of the gel. Comparison between these two results and the first scan of the gel showed that the averaged and zero-scan images provided better contrast, higher contrast-to- noise and higher signal-to-noise than the initial scan. The pixel values (Hounsfield units, HU) in the averaged image were not noticeably elevated, compared to the zero-scan result and the gradients used in the linear extrapolation of the zero-scan images were small and symmetrically distributed around zero. These results indicate that the averaged image was not artificially lightened by the small, additional dose delivered during CT scanning. This work demonstrates the broader usefulness of the zero-scan method as a means to verify the dosimetric accuracy of gel images derived from averaged x-ray CT data
Roelvink, Dano; Costas, Susana
2015-04-01
Geological records contain a wealth of information about accretionary episodes in the life of a coastal profile, such as age and type of the deposits and circumstances during which the accretion took place; of erosional events mainly the final limit of the erosion and circumstances under which the erosion took place can be estimated. To obtain a more complete picture of the events shaping the sedimentary record and transport processes involved, process-based modelling can be a useful tool (e.g. Apotsos et al., 2011). However, application of such modelling to different types of events remains a challenge. In our presentation we intend to show examples of the effects of different events on the stratigraphic record and to discuss the challenges related to the modelling of each of these types of events. The test site chosen is the Costa da Caparica, south of Lisbon, Portugal. The stratigraphic record and progradation rates of the coastal were obtained combining geophysical (Ground Penetrating Radar) and dating (Optically Stimulating Luminescence) techniques, which document very recent ages for the preserved coastal barrier. Within the record, we focus on a period around the big tsunami of 1755, during which the shoreline experienced a long-term prograding trend with evidence of severe erosion events. Rather than trying to exactly reproduce the stratigraphy observed here, we will carry out exploratory simulations to create 'building blocks' of stratigraphy related to the different types of events, which we can loosely compare with observations reported in Rebelo et al. (2013). The model applied for all simulations is XBeach (Roelvink et al., 2009), which is used in three different modes (no short waves, time-varying wave action balance, stationary wave action balance, respectively) to accommodate the impact of tsunamis, storms, and average conditions; for the latter we include the dune and associated processes in a simplified aeolian transport and response model. In all
Alexoff, D.L.; Alexoff, D.L.; Dewey, S.L.; Vaska, P.; Krishnamoorthy, S.; Ferrieri, R.; Schueller, M.; Schlyer, D.; Fowler, J.S.
2011-03-01
PET imaging in plants is receiving increased interest as a new strategy to measure plant responses to environmental stimuli and as a tool for phenotyping genetically engineered plants. PET imaging in plants, however, poses new challenges. In particular, the leaves of most plants are so thin that a large fraction of positrons emitted from PET isotopes ({sup 18}F, {sup 11}C, {sup 13}N) escape while even state-of-the-art PET cameras have significant partial-volume errors for such thin objects. Although these limitations are acknowledged by researchers, little data have been published on them. Here we measured the magnitude and distribution of escaping positrons from the leaf of Nicotiana tabacum for the radionuclides {sup 18}F, {sup 11}C and {sup 13}N using a commercial small-animal PET scanner. Imaging results were compared to radionuclide concentrations measured from dissection and counting and to a Monte Carlo simulation using GATE (Geant4 Application for Tomographic Emission). Simulated and experimentally determined escape fractions were consistent. The fractions of positrons (mean {+-} S.D.) escaping the leaf parenchyma were measured to be 59 {+-} 1.1%, 64 {+-} 4.4% and 67 {+-} 1.9% for {sup 18}F, {sup 11}C and {sup 13}N, respectively. Escape fractions were lower in thicker leaf areas like the midrib. Partial-volume averaging underestimated activity concentrations in the leaf blade by a factor of 10 to 15. The foregoing effects combine to yield PET images whose contrast does not reflect the actual activity concentrations. These errors can be largely corrected by integrating activity along the PET axis perpendicular to the leaf surface, including detection of escaped positrons, and calculating concentration using a measured leaf thickness.
Alexoff, David L., E-mail: alexoff@bnl.gov; Dewey, Stephen L.; Vaska, Paul; Krishnamoorthy, Srilalan; Ferrieri, Richard; Schueller, Michael; Schlyer, David J.; Fowler, Joanna S.
2011-02-15
Introduction: PET imaging in plants is receiving increased interest as a new strategy to measure plant responses to environmental stimuli and as a tool for phenotyping genetically engineered plants. PET imaging in plants, however, poses new challenges. In particular, the leaves of most plants are so thin that a large fraction of positrons emitted from PET isotopes ({sup 18}F, {sup 11}C, {sup 13}N) escape while even state-of-the-art PET cameras have significant partial-volume errors for such thin objects. Although these limitations are acknowledged by researchers, little data have been published on them. Methods: Here we measured the magnitude and distribution of escaping positrons from the leaf of Nicotiana tabacum for the radionuclides {sup 18}F, {sup 11}C and {sup 13}N using a commercial small-animal PET scanner. Imaging results were compared to radionuclide concentrations measured from dissection and counting and to a Monte Carlo simulation using GATE (Geant4 Application for Tomographic Emission). Results: Simulated and experimentally determined escape fractions were consistent. The fractions of positrons (mean{+-}S.D.) escaping the leaf parenchyma were measured to be 59{+-}1.1%, 64{+-}4.4% and 67{+-}1.9% for {sup 18}F, {sup 11}C and {sup 13}N, respectively. Escape fractions were lower in thicker leaf areas like the midrib. Partial-volume averaging underestimated activity concentrations in the leaf blade by a factor of 10 to 15. Conclusions: The foregoing effects combine to yield PET images whose contrast does not reflect the actual activity concentrations. These errors can be largely corrected by integrating activity along the PET axis perpendicular to the leaf surface, including detection of escaped positrons, and calculating concentration using a measured leaf thickness.
Measurements have been performed on the perturbing effect of a number of scattering materials by the 'free-field' neutron leakage spectrum from a Godiva Type Critical Assembly (White Sands Missile Range Fast Burst Reactor). The results of these measurements are interpreted in relation to some of the general parameters characterizing a neutron environment, namely, the average neutron energy >10 KeV, the spectral index and the hardness parameter. Three neutron spectrum measurements have been performed, each under different experimental configurations of scattering materials. Results from these measurements show the following with relation to the spectral index: (1) The neutron environment on the core surface and at 12-inches from the core surface (free-field) yield a spectral index of 6.8, (2) The neutron environment behind a 4.75-inch Plexiglas plate yield 4.6 for the spectral index and (3) The neutron environment behind a 2-inch aluminum plate yield 6.7 for the spectral index. It is concluded that the core surface and the 12-inch from core surface neutron environment are identical with the 'free-field' neutron environment at 20-inches when considering only those neutrons with energy >10 KeV. On the other hand, it appears that the 4.75 inches of Plexiglas severely perturbs the 'free-field' neutron environment, i.e., a much harder neutron spectrum >10 KeV. In the situation where 2-inches of aluminum is used as the perturbing medium, essentially no change in the neutron spectrum >10 KeV is noted
Effective Treatment in Home-Based Services.
Simboli, Tim; Darou, Wes G.
The use of home-based treatment programs has become increasingly popular over the last few years. Such a program is offered by the Youth Services Bureau of Ottawa-Carleton through its Detached Worker Program. This program uses paraprofessionals who employ an eclectic combination of behavioral, client-centered, family and reality therapies. Two…
Shungite carbon catalytic effect on coal treatment
Grigorieva, E.N.; Rozhkova, N.N. [Russian Academy of Sciences, Moscow (Russian Federation). Institute for High Temperature
1999-07-01
The catalytic ability of shungite carbon in reactions of coal organic matter models appeared to be due to its fullerene structure only. Transition metal sulphides present in shungite carbon are not active in the conditions of coal treatment. Shungite carbon was shown to exhibit an acceleration of thermolysis of coal and organic matter models, mainly dehydrogenation. 5 refs., 1 tabs.
Lymphedema as a Cancer Treatment Side Effect
... any new symptoms or a change in symptoms. Treatments for lymphedema are designed to reduce swelling, prevent it from ... the head and neck, you may need physical therapy. Reducing your risk of lymphedema Research continues to look into what factors cause ...
Effect of coconut oil and defaunation treatment on methanogenesis in sheep
Machmüller, Andrea; Soliva, Carla; Kreuzer, Michael
2003-01-01
The present study was conducted to evaluate in vivo the role of rumen ciliate protozoa with respect to the methane-suppressing effect of coconut oil. Three sheep were subjected to a 2 $\\times$ 2 factorial design comprising two types of dietary lipids (50 g$\\cdot$kg$^{-1}$ coconut oil vs. 50 g$\\cdot$kg$^{-1}$ rumen-protected fat) and defaunation treatment (with vs. without). Due to the defaunation treatment, which reduced the rumen ciliate protozoa population by 94% on average, total tract fib...
Effectiveness of Iontophoresis Treatment on Knee Osteoarthritis
Leman Ege; Neslihan Soran; Metin Erçin; Özlem Altındağ
2009-01-01
Objective: Osteoarthritis is the most common joint disease causing disability. The primary goals for osteoarthritis therapy are to relieve pain, maintain or improve functional status, and minimize deformity. Many treatment options, including non-pharmacological and pharmacological measures, have been recommended in the management of osteoarthritis. Among the non-pharmacological approaches is physiotherapy, which involves the use of physical modalities like heat therapy, exercise therapy, elec...