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Sample records for potential weights linear

  1. Use of probabilistic weights to enhance linear regression myoelectric control.

    Science.gov (United States)

    Smith, Lauren H; Kuiken, Todd A; Hargrove, Levi J

    2015-12-01

    Clinically available prostheses for transradial amputees do not allow simultaneous myoelectric control of degrees of freedom (DOFs). Linear regression methods can provide simultaneous myoelectric control, but frequently also result in difficulty with isolating individual DOFs when desired. This study evaluated the potential of using probabilistic estimates of categories of gross prosthesis movement, which are commonly used in classification-based myoelectric control, to enhance linear regression myoelectric control. Gaussian models were fit to electromyogram (EMG) feature distributions for three movement classes at each DOF (no movement, or movement in either direction) and used to weight the output of linear regression models by the probability that the user intended the movement. Eight able-bodied and two transradial amputee subjects worked in a virtual Fitts' law task to evaluate differences in controllability between linear regression and probability-weighted regression for an intramuscular EMG-based three-DOF wrist and hand system. Real-time and offline analyses in able-bodied subjects demonstrated that probability weighting improved performance during single-DOF tasks (p linear regression control. Use of probability weights can improve the ability to isolate individual during linear regression myoelectric control, while maintaining the ability to simultaneously control multiple DOFs.

  2. Use of probabilistic weights to enhance linear regression myoelectric control

    Science.gov (United States)

    Smith, Lauren H.; Kuiken, Todd A.; Hargrove, Levi J.

    2015-12-01

    Objective. Clinically available prostheses for transradial amputees do not allow simultaneous myoelectric control of degrees of freedom (DOFs). Linear regression methods can provide simultaneous myoelectric control, but frequently also result in difficulty with isolating individual DOFs when desired. This study evaluated the potential of using probabilistic estimates of categories of gross prosthesis movement, which are commonly used in classification-based myoelectric control, to enhance linear regression myoelectric control. Approach. Gaussian models were fit to electromyogram (EMG) feature distributions for three movement classes at each DOF (no movement, or movement in either direction) and used to weight the output of linear regression models by the probability that the user intended the movement. Eight able-bodied and two transradial amputee subjects worked in a virtual Fitts’ law task to evaluate differences in controllability between linear regression and probability-weighted regression for an intramuscular EMG-based three-DOF wrist and hand system. Main results. Real-time and offline analyses in able-bodied subjects demonstrated that probability weighting improved performance during single-DOF tasks (p < 0.05) by preventing extraneous movement at additional DOFs. Similar results were seen in experiments with two transradial amputees. Though goodness-of-fit evaluations suggested that the EMG feature distributions showed some deviations from the Gaussian, equal-covariance assumptions used in this experiment, the assumptions were sufficiently met to provide improved performance compared to linear regression control. Significance. Use of probability weights can improve the ability to isolate individual during linear regression myoelectric control, while maintaining the ability to simultaneously control multiple DOFs.

  3. Evaluation of Body Weight and Other Linear Parameters of Marshall ...

    African Journals Online (AJOL)

    This study was designed to evaluate the body weight and other linear parameters of Marshall Broiler for repeatability estimates. A total of one hundred (100) broiler chickens (Marshall) was used in estimating the repeatability of body weight and linear parameters of day old from 2 to 8 weeks of age. Body weight (BW) and ...

  4. Phenotypic Correlations of Body Weight and Linear Body Traits in ...

    African Journals Online (AJOL)

    Data on 126 Sigmond strain of Japanese quail chicks consisting of 42 each of heavy, medium and low body weight lines were used to estimate phenotypic correlations (rp ) among body weight (BWT) and linear body traits at 2, 4 and 6 weeks of age. The linear body traits considered were breast girth (BG), shank length (SL), ...

  5. Weighted functional linear regression models for gene-based association analysis.

    Science.gov (United States)

    Belonogova, Nadezhda M; Svishcheva, Gulnara R; Wilson, James F; Campbell, Harry; Axenovich, Tatiana I

    2018-01-01

    Functional linear regression models are effectively used in gene-based association analysis of complex traits. These models combine information about individual genetic variants, taking into account their positions and reducing the influence of noise and/or observation errors. To increase the power of methods, where several differently informative components are combined, weights are introduced to give the advantage to more informative components. Allele-specific weights have been introduced to collapsing and kernel-based approaches to gene-based association analysis. Here we have for the first time introduced weights to functional linear regression models adapted for both independent and family samples. Using data simulated on the basis of GAW17 genotypes and weights defined by allele frequencies via the beta distribution, we demonstrated that type I errors correspond to declared values and that increasing the weights of causal variants allows the power of functional linear models to be increased. We applied the new method to real data on blood pressure from the ORCADES sample. Five of the six known genes with P models. Moreover, we found an association between diastolic blood pressure and the VMP1 gene (P = 8.18×10-6), when we used a weighted functional model. For this gene, the unweighted functional and weighted kernel-based models had P = 0.004 and 0.006, respectively. The new method has been implemented in the program package FREGAT, which is freely available at https://cran.r-project.org/web/packages/FREGAT/index.html.

  6. Estimation Of Body Weight From Linear Body Measurements In Two ...

    African Journals Online (AJOL)

    The prediction of body weight from body girth, keel length and thigh length was studied using one hundred Ross and one hundred Anak Titan broilers. Data were collected on the birds from day-old to 9 weeks of age. Body measurement was regressed against body weight at 9 weeks of age using simple linear and ...

  7. Weights and linear measurements of the body and some organs of ...

    African Journals Online (AJOL)

    The absolute weights of the body, heart, kidneys, spleen, pancreas, liver, gonads, digestive tract and adrenal glands, as well as the absolute linear measurements of the body, digestive tract and oviduct were determined in adult female and male African white-bellied tree pangolins. The relative weights, relative lengths and ...

  8. Linear-potential values and the 'Shapley family'

    NARCIS (Netherlands)

    Joosten, Reinoud A.M.G.; Peters, Hans; Thuijsman, Frank

    2013-01-01

    We generalize the potentials of Hart & Mas-Colell [1989] by intro-ducing a class of linear potentials for TU-games based on an idea of taxing and redistributing. To each potential an e¢ cient and additivevalue is associated, which attributes to each player his linearly modified contribution to the

  9. A new cellular automata model of traffic flow with negative exponential weighted look-ahead potential

    Science.gov (United States)

    Ma, Xiao; Zheng, Wei-Fan; Jiang, Bao-Shan; Zhang, Ji-Ye

    2016-10-01

    With the development of traffic systems, some issues such as traffic jams become more and more serious. Efficient traffic flow theory is needed to guide the overall controlling, organizing and management of traffic systems. On the basis of the cellular automata model and the traffic flow model with look-ahead potential, a new cellular automata traffic flow model with negative exponential weighted look-ahead potential is presented in this paper. By introducing the negative exponential weighting coefficient into the look-ahead potential and endowing the potential of vehicles closer to the driver with a greater coefficient, the modeling process is more suitable for the driver’s random decision-making process which is based on the traffic environment that the driver is facing. The fundamental diagrams for different weighting parameters are obtained by using numerical simulations which show that the negative exponential weighting coefficient has an obvious effect on high density traffic flux. The complex high density non-linear traffic behavior is also reproduced by numerical simulations. Project supported by the National Natural Science Foundation of China (Grant Nos. 11572264, 11172247, 11402214, and 61373009).

  10. Estimating the Probabilities of Low-Weight Differential and Linear Approximations on PRESENT-like Ciphers

    DEFF Research Database (Denmark)

    Abdelraheem, Mohamed Ahmed

    2012-01-01

    We use large but sparse correlation and transition-difference-probability submatrices to find the best linear and differential approximations respectively on PRESENT-like ciphers. This outperforms the branch and bound algorithm when the number of low-weight differential and linear characteristics...

  11. Applicability of linear and non-linear potential flow models on a Wavestar float

    DEFF Research Database (Denmark)

    Bozonnet, Pauline; Dupin, Victor; Tona, Paolino

    2017-01-01

    as a model based on non-linear potential flow theory and weakscatterer hypothesis are successively considered. Simple tests, such as dip tests, decay tests and captive tests enable to highlight the improvements obtained with the introduction of nonlinearities. Float motion under wave actions and without...... control action, limited to small amplitude motion with a single float, is well predicted by the numerical models, including the linear one. Still, float velocity is better predicted by accounting for non-linear hydrostatic and Froude-Krylov forces.......Numerical models based on potential flow theory, including different types of nonlinearities are compared and validated against experimental data for the Wavestar wave energy converter technology. Exact resolution of the rotational motion, non-linear hydrostatic and Froude-Krylov forces as well...

  12. Wigner weight functions and Weyl symbols of non-negative definite linear operators

    NARCIS (Netherlands)

    Janssen, A.J.E.M.

    1989-01-01

    In this paper we present several necessary and, for radially symmetric functions, necessary and sufficient conditions for a function of two variables to be a Wigner weight function (Weyl symbol of a non-negative definite linear operator of L2(R)). These necessary conditions are in terms of spread

  13. Weighted inequalities for fractional integral operators and linear commutators in the Morrey-type spaces

    Directory of Open Access Journals (Sweden)

    Hua Wang

    2017-01-01

    Full Text Available Abstract In this paper, we first introduce some new Morrey-type spaces containing generalized Morrey space and weighted Morrey space with two weights as special cases. Then we give the weighted strong type and weak type estimates for fractional integral operators I α $I_{\\alpha}$ in these new Morrey-type spaces. Furthermore, the weighted strong type estimate and endpoint estimate of linear commutators [ b , I α ] $[b,I_{\\alpha}]$ formed by b and I α $I_{\\alpha}$ are established. Also we study related problems about two-weight, weak type inequalities for I α $I_{\\alpha}$ and [ b , I α ] $[b,I_{\\alpha}]$ in the Morrey-type spaces and give partial results.

  14. On the nucleon-nucleon potential obtained from non-linear coupling

    International Nuclear Information System (INIS)

    El Ghabaty, S.S.

    1975-07-01

    The static limit of a pseudoscalar symmetric meson theory of nuclear forces is examined. The Born-Oppenheimer potential is determined for the case of two very heavy nucleons exchanging pseudoscalar isovector pions with non-linear coupling. It is found that the non-linear terms induced by the γ 5 coupling are cancelled by the additional pion-nucleon coupling of the non-linear sigma model. The nucleon-nucleon potential thus obtained is the same as the Yukava potential except for strength at different separations between the two nucleons

  15. Predicting birth weight with conditionally linear transformation models.

    Science.gov (United States)

    Möst, Lisa; Schmid, Matthias; Faschingbauer, Florian; Hothorn, Torsten

    2016-12-01

    Low and high birth weight (BW) are important risk factors for neonatal morbidity and mortality. Gynecologists must therefore accurately predict BW before delivery. Most prediction formulas for BW are based on prenatal ultrasound measurements carried out within one week prior to birth. Although successfully used in clinical practice, these formulas focus on point predictions of BW but do not systematically quantify uncertainty of the predictions, i.e. they result in estimates of the conditional mean of BW but do not deliver prediction intervals. To overcome this problem, we introduce conditionally linear transformation models (CLTMs) to predict BW. Instead of focusing only on the conditional mean, CLTMs model the whole conditional distribution function of BW given prenatal ultrasound parameters. Consequently, the CLTM approach delivers both point predictions of BW and fetus-specific prediction intervals. Prediction intervals constitute an easy-to-interpret measure of prediction accuracy and allow identification of fetuses subject to high prediction uncertainty. Using a data set of 8712 deliveries at the Perinatal Centre at the University Clinic Erlangen (Germany), we analyzed variants of CLTMs and compared them to standard linear regression estimation techniques used in the past and to quantile regression approaches. The best-performing CLTM variant was competitive with quantile regression and linear regression approaches in terms of conditional coverage and average length of the prediction intervals. We propose that CLTMs be used because they are able to account for possible heteroscedasticity, kurtosis, and skewness of the distribution of BWs. © The Author(s) 2014.

  16. Linear, Transfinite and Weighted Method for Interpolation from Grid Lines Applied to OCT Images

    DEFF Research Database (Denmark)

    Lindberg, Anne-Sofie Wessel; Jørgensen, Thomas Martini; Dahl, Vedrana Andersen

    2018-01-01

    of a square grid, but are unknown inside each square. To view these values as an image, intensities need to be interpolated at regularly spaced pixel positions. In this paper we evaluate three methods for interpolation from grid lines: linear, transfinite and weighted. The linear method does not preserve...... and the stability of the linear method further away. An important parameter influencing the performance of the interpolation methods is the upsampling rate. We perform an extensive evaluation of the three interpolation methods across a range of upsampling rates. Our statistical analysis shows significant difference...... in the performance of the three methods. We find that the transfinite interpolation works well for small upsampling rates and the proposed weighted interpolation method performs very well for all upsampling rates typically used in practice. On the basis of these findings we propose an approach for combining two OCT...

  17. Weighted H∞ Filtering for a Class of Switched Linear Systems with Additive Time-Varying Delays

    Directory of Open Access Journals (Sweden)

    Li-li Li

    2015-01-01

    Full Text Available This paper is concerned with the problem of weighted H∞ filtering for a class of switched linear systems with two additive time-varying delays, which represent a general class of switched time-delay systems with strong practical background. Combining average dwell time (ADT technique with piecewise Lyapunov functionals, sufficient conditions are established to guarantee the exponential stability and weighted H∞ performance for the filtering error systems. The parameters of the designed switched filters are obtained by solving linear matrix inequalities (LMIs. A modification of Jensen integral inequality is exploited to derive results with less theoretical conservatism and computational complexity. Finally, two examples are given to demonstrate the effectiveness of the proposed method.

  18. Burgers' turbulence problem with linear or quadratic external potential

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole Eiler; Leonenko, N.N.

    2005-01-01

    We consider solutions of Burgers' equation with linear or quadratic external potential and stationary random initial conditions of Ornstein-Uhlenbeck type. We study a class of limit laws that correspond to a scale renormalization of the solutions.......We consider solutions of Burgers' equation with linear or quadratic external potential and stationary random initial conditions of Ornstein-Uhlenbeck type. We study a class of limit laws that correspond to a scale renormalization of the solutions....

  19. A Cross-Domain Collaborative Filtering Algorithm Based on Feature Construction and Locally Weighted Linear Regression.

    Science.gov (United States)

    Yu, Xu; Lin, Jun-Yu; Jiang, Feng; Du, Jun-Wei; Han, Ji-Zhong

    2018-01-01

    Cross-domain collaborative filtering (CDCF) solves the sparsity problem by transferring rating knowledge from auxiliary domains. Obviously, different auxiliary domains have different importance to the target domain. However, previous works cannot evaluate effectively the significance of different auxiliary domains. To overcome this drawback, we propose a cross-domain collaborative filtering algorithm based on Feature Construction and Locally Weighted Linear Regression (FCLWLR). We first construct features in different domains and use these features to represent different auxiliary domains. Thus the weight computation across different domains can be converted as the weight computation across different features. Then we combine the features in the target domain and in the auxiliary domains together and convert the cross-domain recommendation problem into a regression problem. Finally, we employ a Locally Weighted Linear Regression (LWLR) model to solve the regression problem. As LWLR is a nonparametric regression method, it can effectively avoid underfitting or overfitting problem occurring in parametric regression methods. We conduct extensive experiments to show that the proposed FCLWLR algorithm is effective in addressing the data sparsity problem by transferring the useful knowledge from the auxiliary domains, as compared to many state-of-the-art single-domain or cross-domain CF methods.

  20. A Cross-Domain Collaborative Filtering Algorithm Based on Feature Construction and Locally Weighted Linear Regression

    Directory of Open Access Journals (Sweden)

    Xu Yu

    2018-01-01

    Full Text Available Cross-domain collaborative filtering (CDCF solves the sparsity problem by transferring rating knowledge from auxiliary domains. Obviously, different auxiliary domains have different importance to the target domain. However, previous works cannot evaluate effectively the significance of different auxiliary domains. To overcome this drawback, we propose a cross-domain collaborative filtering algorithm based on Feature Construction and Locally Weighted Linear Regression (FCLWLR. We first construct features in different domains and use these features to represent different auxiliary domains. Thus the weight computation across different domains can be converted as the weight computation across different features. Then we combine the features in the target domain and in the auxiliary domains together and convert the cross-domain recommendation problem into a regression problem. Finally, we employ a Locally Weighted Linear Regression (LWLR model to solve the regression problem. As LWLR is a nonparametric regression method, it can effectively avoid underfitting or overfitting problem occurring in parametric regression methods. We conduct extensive experiments to show that the proposed FCLWLR algorithm is effective in addressing the data sparsity problem by transferring the useful knowledge from the auxiliary domains, as compared to many state-of-the-art single-domain or cross-domain CF methods.

  1. Newborn length predicts early infant linear growth retardation and disproportionately high weight gain in a low-income population.

    Science.gov (United States)

    Berngard, Samuel Clark; Berngard, Jennifer Bishop; Krebs, Nancy F; Garcés, Ana; Miller, Leland V; Westcott, Jamie; Wright, Linda L; Kindem, Mark; Hambidge, K Michael

    2013-12-01

    Stunting is prevalent by the age of 6 months in the indigenous population of the Western Highlands of Guatemala. The objective of this study was to determine the time course and predictors of linear growth failure and weight-for-age in early infancy. One hundred and forty eight term newborns had measurements of length and weight in their homes, repeated at 3 and 6 months. Maternal measurements were also obtained. Mean ± SD length-for-age Z-score (LAZ) declined from newborn -1.0 ± 1.01 to -2.20 ± 1.05 and -2.26 ± 1.01 at 3 and 6 months respectively. Stunting rates for newborn, 3 and 6 months were 47%, 53% and 56% respectively. A multiple regression model (R(2) = 0.64) demonstrated that the major predictor of LAZ at 3 months was newborn LAZ with the other predictors being newborn weight-for-age Z-score (WAZ), gender and maternal education∗maternal age interaction. Because WAZ remained essentially constant and LAZ declined during the same period, weight-for-length Z-score (WLZ) increased from -0.44 to +1.28 from birth to 3 months. The more severe the linear growth failure, the greater WAZ was in proportion to the LAZ. The primary conclusion is that impaired fetal linear growth is the major predictor of early infant linear growth failure indicating that prevention needs to start with maternal interventions. © 2013.

  2. voom: Precision weights unlock linear model analysis tools for RNA-seq read counts.

    Science.gov (United States)

    Law, Charity W; Chen, Yunshun; Shi, Wei; Smyth, Gordon K

    2014-02-03

    New normal linear modeling strategies are presented for analyzing read counts from RNA-seq experiments. The voom method estimates the mean-variance relationship of the log-counts, generates a precision weight for each observation and enters these into the limma empirical Bayes analysis pipeline. This opens access for RNA-seq analysts to a large body of methodology developed for microarrays. Simulation studies show that voom performs as well or better than count-based RNA-seq methods even when the data are generated according to the assumptions of the earlier methods. Two case studies illustrate the use of linear modeling and gene set testing methods.

  3. On the Performance of Linear Decreasing Inertia Weight Particle Swarm Optimization for Global Optimization

    Science.gov (United States)

    Arasomwan, Martins Akugbe; Adewumi, Aderemi Oluyinka

    2013-01-01

    Linear decreasing inertia weight (LDIW) strategy was introduced to improve on the performance of the original particle swarm optimization (PSO). However, linear decreasing inertia weight PSO (LDIW-PSO) algorithm is known to have the shortcoming of premature convergence in solving complex (multipeak) optimization problems due to lack of enough momentum for particles to do exploitation as the algorithm approaches its terminal point. Researchers have tried to address this shortcoming by modifying LDIW-PSO or proposing new PSO variants. Some of these variants have been claimed to outperform LDIW-PSO. The major goal of this paper is to experimentally establish the fact that LDIW-PSO is very much efficient if its parameters are properly set. First, an experiment was conducted to acquire a percentage value of the search space limits to compute the particle velocity limits in LDIW-PSO based on commonly used benchmark global optimization problems. Second, using the experimentally obtained values, five well-known benchmark optimization problems were used to show the outstanding performance of LDIW-PSO over some of its competitors which have in the past claimed superiority over it. Two other recent PSO variants with different inertia weight strategies were also compared with LDIW-PSO with the latter outperforming both in the simulation experiments conducted. PMID:24324383

  4. On the Relationship Between Confidence Sets and Exchangeable Weights in Multiple Linear Regression.

    Science.gov (United States)

    Pek, Jolynn; Chalmers, R Philip; Monette, Georges

    2016-01-01

    When statistical models are employed to provide a parsimonious description of empirical relationships, the extent to which strong conclusions can be drawn rests on quantifying the uncertainty in parameter estimates. In multiple linear regression (MLR), regression weights carry two kinds of uncertainty represented by confidence sets (CSs) and exchangeable weights (EWs). Confidence sets quantify uncertainty in estimation whereas the set of EWs quantify uncertainty in the substantive interpretation of regression weights. As CSs and EWs share certain commonalities, we clarify the relationship between these two kinds of uncertainty about regression weights. We introduce a general framework describing how CSs and the set of EWs for regression weights are estimated from the likelihood-based and Wald-type approach, and establish the analytical relationship between CSs and sets of EWs. With empirical examples on posttraumatic growth of caregivers (Cadell et al., 2014; Schneider, Steele, Cadell & Hemsworth, 2011) and on graduate grade point average (Kuncel, Hezlett & Ones, 2001), we illustrate the usefulness of CSs and EWs for drawing strong scientific conclusions. We discuss the importance of considering both CSs and EWs as part of the scientific process, and provide an Online Appendix with R code for estimating Wald-type CSs and EWs for k regression weights.

  5. A note on multi-criteria inventory classification using weighted linear optimization

    Directory of Open Access Journals (Sweden)

    Rezaei Jafar

    2010-01-01

    Full Text Available Recently, Ramanathan (R., Ramanathan, ABC inventory classification with multiple-criteria using weighted linear optimization, Computer and Operations Research, 33(3 (2006 695-700 introduced a simple DEA-like model to classify inventory items on the basis of multiple criteria. However, the classification results produced by Ramanathan are not consistent with the domination concept encouraged some researchers to extend his model. In this paper, we produce the correct results and compare them to the original results and those of the extended models. We also improve this model to rank items with an optimal score of 1 using a cross-efficiency technique. The classification results are considerably different from the original results. Despite the fact that the correct results are obtained in this paper, there is no significant difference between the original model and its extensions, while the original model is more simple and suitable for the situations in which decision-maker cannot assign specific weights to individual criteria.

  6. SAS macro programs for geographically weighted generalized linear modeling with spatial point data: applications to health research.

    Science.gov (United States)

    Chen, Vivian Yi-Ju; Yang, Tse-Chuan

    2012-08-01

    An increasing interest in exploring spatial non-stationarity has generated several specialized analytic software programs; however, few of these programs can be integrated natively into a well-developed statistical environment such as SAS. We not only developed a set of SAS macro programs to fill this gap, but also expanded the geographically weighted generalized linear modeling (GWGLM) by integrating the strengths of SAS into the GWGLM framework. Three features distinguish our work. First, the macro programs of this study provide more kernel weighting functions than the existing programs. Second, with our codes the users are able to better specify the bandwidth selection process compared to the capabilities of existing programs. Third, the development of the macro programs is fully embedded in the SAS environment, providing great potential for future exploration of complicated spatially varying coefficient models in other disciplines. We provided three empirical examples to illustrate the use of the SAS macro programs and demonstrated the advantages explained above. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  7. Weight gain potential affects pregnancy rates in bovine embryo recipients raised under pasture conditions.

    Science.gov (United States)

    Fernandes, Carlos Antonio de Carvalho; Palhao, Miller Pereira; Figueiredo, Ana Cristina Silva; Ribeiro, Josiane Rossi; Fonseca e Silva, Fabyano; Viana, Joao Henrique Moreira

    2016-01-01

    The aim of the present study was to evaluate the effect of differences in body weight gain after embryo transfer on the pregnancy rates of crossbred heifers used as recipients and raised under a grazing system. The study was performed during the dry (April to September) and the rainy (October to March) seasons. The embryos transferred were produced by in vitro fertilization. The body weight of each recipient was measured immediately before the embryo transfer and 23 to 25 days later, when the diagnosis of pregnancy was performed by ultrasonography. The associations among initial body weight (IBW), daily body weight gain (DWG), season, and pregnancy rate were evaluated using a logistic procedure that included the effect of the IBW, season, and linear and quadratic effects of the DWG. Altogether, there was no effect of season and pregnancy rates did not change between the dry and rainy seasons (42.3 vs. 45.8%, respectively; P > 0.05). However, the pregnancy rate was greater in the recipients with daily body weight gains over 250 g/day, regardless of the season. In addition, the pregnancy rate of the recipients was better (P 06703 + 0.0108 * DWG - 0.00002 * DWG ^ 2)))/(1 + Exp((-1.6703 + 0.0108 * DWG - 0.00002 * DWG ^ 2))). In conclusion, body weight gain potential is a critical factor for the pregnancy rates of in vitro embryo recipients managed under grazing systems.

  8. User's Guide to the Weighted-Multiple-Linear Regression Program (WREG version 1.0)

    Science.gov (United States)

    Eng, Ken; Chen, Yin-Yu; Kiang, Julie.E.

    2009-01-01

    Streamflow is not measured at every location in a stream network. Yet hydrologists, State and local agencies, and the general public still seek to know streamflow characteristics, such as mean annual flow or flood flows with different exceedance probabilities, at ungaged basins. The goals of this guide are to introduce and familiarize the user with the weighted multiple-linear regression (WREG) program, and to also provide the theoretical background for program features. The program is intended to be used to develop a regional estimation equation for streamflow characteristics that can be applied at an ungaged basin, or to improve the corresponding estimate at continuous-record streamflow gages with short records. The regional estimation equation results from a multiple-linear regression that relates the observable basin characteristics, such as drainage area, to streamflow characteristics.

  9. Incidence And Potential Risk Factors Of Low Birth Weight Among ...

    African Journals Online (AJOL)

    Incidence And Potential Risk Factors Of Low Birth Weight Among Full Term Deliveries. ... (LBW) is a reliable indicator in monitoring and evaluating the success of maternal and child ... Key words: Low birth weight- incidence- associated factors.

  10. A Secondary Antibody-Detecting Molecular Weight Marker with Mouse and Rabbit IgG Fc Linear Epitopes for Western Blot Analysis.

    Science.gov (United States)

    Lin, Wen-Wei; Chen, I-Ju; Cheng, Ta-Chun; Tung, Yi-Ching; Chu, Pei-Yu; Chuang, Chih-Hung; Hsieh, Yuan-Chin; Huang, Chien-Chiao; Wang, Yeng-Tseng; Kao, Chien-Han; Roffler, Steve R; Cheng, Tian-Lu

    2016-01-01

    Molecular weight markers that can tolerate denaturing conditions and be auto-detected by secondary antibodies offer great efficacy and convenience for Western Blotting. Here, we describe M&R LE protein markers which contain linear epitopes derived from the heavy chain constant regions of mouse and rabbit immunoglobulin G (IgG Fc LE). These markers can be directly recognized and stained by a wide range of anti-mouse and anti-rabbit secondary antibodies. We selected three mouse (M1, M2 and M3) linear IgG1 and three rabbit (R1, R2 and R3) linear IgG heavy chain epitope candidates based on their respective crystal structures. Western blot analysis indicated that M2 and R2 linear epitopes are effectively recognized by anti-mouse and anti-rabbit secondary antibodies, respectively. We fused the M2 and R2 epitopes (M&R LE) and incorporated the polypeptide in a range of 15-120 kDa auto-detecting markers (M&R LE protein marker). The M&R LE protein marker can be auto-detected by anti-mouse and anti-rabbit IgG secondary antibodies in standard immunoblots. Linear regression analysis of the M&R LE protein marker plotted as gel mobility versus the log of the marker molecular weights revealed good linearity with a correlation coefficient R2 value of 0.9965, indicating that the M&R LE protein marker displays high accuracy for determining protein molecular weights. This accurate, regular and auto-detected M&R LE protein marker may provide a simple, efficient and economical tool for protein analysis.

  11. Quantifying feedforward control: a linear scaling model for fingertip forces and object weight.

    Science.gov (United States)

    Lu, Ying; Bilaloglu, Seda; Aluru, Viswanath; Raghavan, Preeti

    2015-07-01

    The ability to predict the optimal fingertip forces according to object properties before the object is lifted is known as feedforward control, and it is thought to occur due to the formation of internal representations of the object's properties. The control of fingertip forces to objects of different weights has been studied extensively by using a custom-made grip device instrumented with force sensors. Feedforward control is measured by the rate of change of the vertical (load) force before the object is lifted. However, the precise relationship between the rate of change of load force and object weight and how it varies across healthy individuals in a population is not clearly understood. Using sets of 10 different weights, we have shown that there is a log-linear relationship between the fingertip load force rates and weight among neurologically intact individuals. We found that after one practice lift, as the weight increased, the peak load force rate (PLFR) increased by a fixed percentage, and this proportionality was common among the healthy subjects. However, at any given weight, the level of PLFR varied across individuals and was related to the efficiency of the muscles involved in lifting the object, in this case the wrist and finger extensor muscles. These results quantify feedforward control during grasp and lift among healthy individuals and provide new benchmarks to interpret data from neurologically impaired populations as well as a means to assess the effect of interventions on restoration of feedforward control and its relationship to muscular control. Copyright © 2015 the American Physiological Society.

  12. Method validation using weighted linear regression models for quantification of UV filters in water samples.

    Science.gov (United States)

    da Silva, Claudia Pereira; Emídio, Elissandro Soares; de Marchi, Mary Rosa Rodrigues

    2015-01-01

    This paper describes the validation of a method consisting of solid-phase extraction followed by gas chromatography-tandem mass spectrometry for the analysis of the ultraviolet (UV) filters benzophenone-3, ethylhexyl salicylate, ethylhexyl methoxycinnamate and octocrylene. The method validation criteria included evaluation of selectivity, analytical curve, trueness, precision, limits of detection and limits of quantification. The non-weighted linear regression model has traditionally been used for calibration, but it is not necessarily the optimal model in all cases. Because the assumption of homoscedasticity was not met for the analytical data in this work, a weighted least squares linear regression was used for the calibration method. The evaluated analytical parameters were satisfactory for the analytes and showed recoveries at four fortification levels between 62% and 107%, with relative standard deviations less than 14%. The detection limits ranged from 7.6 to 24.1 ng L(-1). The proposed method was used to determine the amount of UV filters in water samples from water treatment plants in Araraquara and Jau in São Paulo, Brazil. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Associations of infant feeding and timing of linear growth and relative weight gain during early life with childhood body composition

    NARCIS (Netherlands)

    de Beer, M.; Vrijkotte, T.G.M.; Fall, C.H.D.; Eijsden, M.; Osmond, C.; Gemke, R.J.B.J.

    2015-01-01

    Background:Growth and feeding during infancy have been associated with later life body mass index. However, the associations of infant feeding, linear growth and weight gain relative to linear growth with separate components of body composition remain unclear.Methods:Of 5551 children with collected

  14. Associations of infant feeding and timing of linear growth and relative weight gain during early life with childhood body composition

    NARCIS (Netherlands)

    de Beer, M.; Vrijkotte, T. G. M.; Fall, C. H. D.; van Eijsden, M.; Osmond, C.; Gemke, R. J. B. J.

    2015-01-01

    Growth and feeding during infancy have been associated with later life body mass index. However, the associations of infant feeding, linear growth and weight gain relative to linear growth with separate components of body composition remain unclear. Of 5551 children with collected growth and

  15. Evaluation of linear regression techniques for atmospheric applications: the importance of appropriate weighting

    Directory of Open Access Journals (Sweden)

    C. Wu

    2018-03-01

    Full Text Available Linear regression techniques are widely used in atmospheric science, but they are often improperly applied due to lack of consideration or inappropriate handling of measurement uncertainty. In this work, numerical experiments are performed to evaluate the performance of five linear regression techniques, significantly extending previous works by Chu and Saylor. The five techniques are ordinary least squares (OLS, Deming regression (DR, orthogonal distance regression (ODR, weighted ODR (WODR, and York regression (YR. We first introduce a new data generation scheme that employs the Mersenne twister (MT pseudorandom number generator. The numerical simulations are also improved by (a refining the parameterization of nonlinear measurement uncertainties, (b inclusion of a linear measurement uncertainty, and (c inclusion of WODR for comparison. Results show that DR, WODR and YR produce an accurate slope, but the intercept by WODR and YR is overestimated and the degree of bias is more pronounced with a low R2 XY dataset. The importance of a properly weighting parameter λ in DR is investigated by sensitivity tests, and it is found that an improper λ in DR can lead to a bias in both the slope and intercept estimation. Because the λ calculation depends on the actual form of the measurement error, it is essential to determine the exact form of measurement error in the XY data during the measurement stage. If a priori error in one of the variables is unknown, or the measurement error described cannot be trusted, DR, WODR and YR can provide the least biases in slope and intercept among all tested regression techniques. For these reasons, DR, WODR and YR are recommended for atmospheric studies when both X and Y data have measurement errors. An Igor Pro-based program (Scatter Plot was developed to facilitate the implementation of error-in-variables regressions.

  16. Evaluation of linear regression techniques for atmospheric applications: the importance of appropriate weighting

    Science.gov (United States)

    Wu, Cheng; Zhen Yu, Jian

    2018-03-01

    Linear regression techniques are widely used in atmospheric science, but they are often improperly applied due to lack of consideration or inappropriate handling of measurement uncertainty. In this work, numerical experiments are performed to evaluate the performance of five linear regression techniques, significantly extending previous works by Chu and Saylor. The five techniques are ordinary least squares (OLS), Deming regression (DR), orthogonal distance regression (ODR), weighted ODR (WODR), and York regression (YR). We first introduce a new data generation scheme that employs the Mersenne twister (MT) pseudorandom number generator. The numerical simulations are also improved by (a) refining the parameterization of nonlinear measurement uncertainties, (b) inclusion of a linear measurement uncertainty, and (c) inclusion of WODR for comparison. Results show that DR, WODR and YR produce an accurate slope, but the intercept by WODR and YR is overestimated and the degree of bias is more pronounced with a low R2 XY dataset. The importance of a properly weighting parameter λ in DR is investigated by sensitivity tests, and it is found that an improper λ in DR can lead to a bias in both the slope and intercept estimation. Because the λ calculation depends on the actual form of the measurement error, it is essential to determine the exact form of measurement error in the XY data during the measurement stage. If a priori error in one of the variables is unknown, or the measurement error described cannot be trusted, DR, WODR and YR can provide the least biases in slope and intercept among all tested regression techniques. For these reasons, DR, WODR and YR are recommended for atmospheric studies when both X and Y data have measurement errors. An Igor Pro-based program (Scatter Plot) was developed to facilitate the implementation of error-in-variables regressions.

  17. Solvable linear potentials in the Dirac equation

    International Nuclear Information System (INIS)

    Dominguez-Adame, F.; Gonzalez, M.A.

    1990-01-01

    The Dirac equation for some linear potentials leading to Schroedinger-like oscillator equations for the upper and lower components of the Dirac spinor have been solved. Energy levels for the bound states appear in pairs, so that both particles and antiparticles may be bound with the same energy. For weak coupling, the spacing between levels is proportional to the coupling constant while in the strong limit those levels are depressed compared to the nonrelativistic ones

  18. The linear potential propagator via wave function expansion

    International Nuclear Information System (INIS)

    Nassar, Antonio B.; Cattani, Mauro S.D.

    2002-01-01

    We evaluate the quantum propagator for the motion of a particle in a linear potential via a recently developed formalism [A.B. Nassar et al., Phys. Rev. E56, 1230, (1997)]. In this formalism, the propagator comes about as a type of expansion of the wave function over the space of the initial velocities. (author)

  19. Complex energy eigenvalues of a linear potential with a parabolical barrier

    International Nuclear Information System (INIS)

    Malherbe, J.B.

    1978-01-01

    The physical meaning and restrictions of complex energy eigenvalues are briefly discussed. It is indicated that a quasi-stationary phase describes an idealised disintegration system. Approximate resonance-eigenvalues of the one dimensional Schrodinger equation with a linear potential and parabolic barrier are calculated by means of Connor's semiclassical method. This method is based on the generalized WKB-method of Miller and Good. The results obtained confirm the correctness of a model representation which explains the unusual distribution of eigenvalues by certain other linear potentials in a complex energy level [af

  20. Variable-Weighted Linear Combination Model for Landslide Susceptibility Mapping: Case Study in the Shennongjia Forestry District, China

    Directory of Open Access Journals (Sweden)

    Wei Chen

    2017-11-01

    Full Text Available A landslide susceptibility map plays an essential role in urban and rural planning. The main purpose of this study is to establish a variable-weighted linear combination model (VWLC and assess its potential for landslide susceptibility mapping. Firstly, different objective methods are employed for data processing rather than the frequently-used subjective judgments: K-means clustering is used for classification; binarization is introduced to determine buffer length thresholds for locational elements (road, river, and fault; landslide area density is adopted as the contribution index; and a correlation analysis is conducted for suitable factor selection. Secondly, considering the dimension changes of the preference matrix varying with the different locations of the mapping cells, the variable weights of each optimal factor are determined based on the improved analytic hierarchy process (AHP. On this basis, the VWLC model is established and applied to regional landslide susceptibility mapping for the Shennongjia Forestry District, China, where shallow landslides frequently occur. The obtained map is then compared with a map using the traditional WLC, and the results of the comparison show that VWLC is more reasonable, with a higher accuracy, and can be used anywhere that has the same or similar geological and topographical conditions.

  1. On the interpretation of weight vectors of linear models in multivariate neuroimaging.

    Science.gov (United States)

    Haufe, Stefan; Meinecke, Frank; Görgen, Kai; Dähne, Sven; Haynes, John-Dylan; Blankertz, Benjamin; Bießmann, Felix

    2014-02-15

    The increase in spatiotemporal resolution of neuroimaging devices is accompanied by a trend towards more powerful multivariate analysis methods. Often it is desired to interpret the outcome of these methods with respect to the cognitive processes under study. Here we discuss which methods allow for such interpretations, and provide guidelines for choosing an appropriate analysis for a given experimental goal: For a surgeon who needs to decide where to remove brain tissue it is most important to determine the origin of cognitive functions and associated neural processes. In contrast, when communicating with paralyzed or comatose patients via brain-computer interfaces, it is most important to accurately extract the neural processes specific to a certain mental state. These equally important but complementary objectives require different analysis methods. Determining the origin of neural processes in time or space from the parameters of a data-driven model requires what we call a forward model of the data; such a model explains how the measured data was generated from the neural sources. Examples are general linear models (GLMs). Methods for the extraction of neural information from data can be considered as backward models, as they attempt to reverse the data generating process. Examples are multivariate classifiers. Here we demonstrate that the parameters of forward models are neurophysiologically interpretable in the sense that significant nonzero weights are only observed at channels the activity of which is related to the brain process under study. In contrast, the interpretation of backward model parameters can lead to wrong conclusions regarding the spatial or temporal origin of the neural signals of interest, since significant nonzero weights may also be observed at channels the activity of which is statistically independent of the brain process under study. As a remedy for the linear case, we propose a procedure for transforming backward models into forward

  2. Self-driven particles in linear flows and trapped in a harmonic potential

    Science.gov (United States)

    Sandoval, Mario; Hidalgo-Gonzalez, Julio C.; Jimenez-Aquino, Jose I.

    2018-03-01

    We present analytical expressions for the mean-square displacement of self-driven particles in general linear flows and trapped in a harmonic potential. The general expressions are applied to three types of linear flows, namely, shear flow, solid-body rotation flow, and extensional flow. By using Brownian dynamics simulations, the effect of trapping and external linear flows on the particles' distribution is also elucidated. These simulations also enabled us to validate our theoretical results.

  3. Weighted potential and consistency: a unified approach to values for TU-games (Revised version)

    NARCIS (Netherlands)

    Driessen, Theo; Radzik, T.; Wanink, R.G.

    1998-01-01

    A value on the set {\\bf G} of all transferable utility games is said to have a weighted potential representation if there exists a potential function $P: {\\bf G} \\to {\\mathbb{R}}$, associated with a collection of weights, such that, for every game and every player, an appropriately chosen weighted

  4. Radiation transmission of heavyweight and normal-weight concretes containing colemanite for 6 MV and 18 MV X-rays using linear accelerator

    International Nuclear Information System (INIS)

    Demir, F.; Budak, G.; Sahin, R.; Karabulut, A.; Oltulu, M.; Serifoglu, K.; Un, A.

    2010-01-01

    Accurate measurements have been made to determine radiation transmission of concretes produced with barite, colemanite and normal aggregate by using beam transmission method for 6 and 18 MV X-rays with a linear accelerator (LINAC). Linear attenuation coefficients of thirteen heavy- and four normal-weight concretes were calculated. It was determined that linear attenuation coefficient (μ, cm -1 ) decreased with colemanite concentration and increased with barite concentration in both types of the concretes.

  5. The linear programming bound for binary linear codes

    NARCIS (Netherlands)

    Brouwer, A.E.

    1993-01-01

    Combining Delsarte's (1973) linear programming bound with the information that certain weights cannot occur, new upper bounds for dmin (n,k), the maximum possible minimum distance of a binary linear code with given word length n and dimension k, are derived.

  6. Quantum reflection in the linearly downward potential

    Science.gov (United States)

    Chamnan, N.; Krunavakarn, B.

    2017-09-01

    In this work, the motion of a particle in one dimension under the influence of the linearly downward potential well is studied within the context of the non-relativistic quantum mechanics. The attention is paid on the paradoxical phenomenon of the reflection of a particle that is in contrast between classical and quantum physics. Classically, the reflection effect occurs only at a potential barrier. To demonstrate such counter-intuitive phenomenon, the Schrödinger equation is solved to obtain the reflection coefficient in the scattering state by considering an incident particle that is represented by a monochromatic plane wave having an energy E > 0, propagates freely from left to right, pass through the potential well. The continuity conditions at boundaries give the desired result that is expressed in terms of the Airy functions which depends on the incident energy E, the strength jV 0 j and the range L of the well. The value of the reflection coefficient R lies in the interval 0 < R < 1, and its behavior is the decreasing function with respect to the range L.

  7. Pulsed NMR studies of crosslinking and entanglements in high molecular weight linear polydimethylsiloxanes

    International Nuclear Information System (INIS)

    Folland, R.; Charlesby, A.

    1977-01-01

    Pulsed NMR studies of proton spin relaxation are used to investigate both radiation-induced cross linking and entanglements in three high molecular weight linear polydimethylsiloxanes (Msub(w) = 26,000, 63,000 and 110,000). Particular emphasis is placed on the spin-spin relaxation since this is determined by the slower relative translational motions of the polymer chains and hence profoundly affected by the presence of intermolecular couplings such as crosslinks or entanglements. The spin-lattice relaxation times, T 1 , are determined by the fast anisotropic chain rotations and are rather insensitive to such intermolecular couplings. The spin-spin relaxation in these materials is represented by a double exponential decay involving two time constants, Tsub(2S) and Tsub(2L). The shorter component, Tsub(2S), is attributed to network material, which may be either of a dynamic form arising from temporary entanglements or of a permanent nature due to crosslinks. The concentration of entanglements depends on the initial molecular weight of the sample whereas the concentration of crosslinks is a function of the radiation dose. The longer component, Tsub(2L), is attributed to the non-network molecules. On the time scale of the NMR measurements the entanglements are shown to act in the same way as crosslinks. The variation of the relative proportions of network and non-network material with dose is shown to be accounted for by using standard gelation theory when allowance is made for the initial effective crosslink density due to entanglements. The analysis provides a value for the average molecular weight per entanglement point of 27,000 +- 1000 which is consistent with the critical molecular weight for entanglements of 29,000. The dependences of Tsub(2S) and Tsub(2L) on dose and molecular weight are also discussed in terms of the molecular motion. (author)

  8. Improvement of resolution in full-view linear-array photoacoustic computed tomography using a novel adaptive weighting method

    Science.gov (United States)

    Omidi, Parsa; Diop, Mamadou; Carson, Jeffrey; Nasiriavanaki, Mohammadreza

    2017-03-01

    Linear-array-based photoacoustic computed tomography is a popular methodology for deep and high resolution imaging. However, issues such as phase aberration, side-lobe effects, and propagation limitations deteriorate the resolution. The effect of phase aberration due to acoustic attenuation and constant assumption of the speed of sound (SoS) can be reduced by applying an adaptive weighting method such as the coherence factor (CF). Utilizing an adaptive beamforming algorithm such as the minimum variance (MV) can improve the resolution at the focal point by eliminating the side-lobes. Moreover, invisibility of directional objects emitting parallel to the detection plane, such as vessels and other absorbing structures stretched in the direction perpendicular to the detection plane can degrade resolution. In this study, we propose a full-view array level weighting algorithm in which different weighs are assigned to different positions of the linear array based on an orientation algorithm which uses the histogram of oriented gradient (HOG). Simulation results obtained from a synthetic phantom show the superior performance of the proposed method over the existing reconstruction methods.

  9. Linear Energy Transfer-Guided Optimization in Intensity Modulated Proton Therapy: Feasibility Study and Clinical Potential

    Energy Technology Data Exchange (ETDEWEB)

    Giantsoudi, Drosoula, E-mail: dgiantsoudi@partners.org [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts (United States); Grassberger, Clemens; Craft, David; Niemierko, Andrzej; Trofimov, Alexei; Paganetti, Harald [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts (United States)

    2013-09-01

    Purpose: To investigate the feasibility and potential clinical benefit of linear energy transfer (LET) guided plan optimization in intensity modulated proton therapy (IMPT). Methods and Materials: A multicriteria optimization (MCO) module was used to generate a series of Pareto-optimal IMPT base plans (BPs), corresponding to defined objectives, for 5 patients with head-and-neck cancer and 2 with pancreatic cancer. A Monte Carlo platform was used to calculate dose and LET distributions for each BP. A custom-designed MCO navigation module allowed the user to interpolate between BPs to produce deliverable Pareto-optimal solutions. Differences among the BPs were evaluated for each patient, based on dose–volume and LET–volume histograms and 3-dimensional distributions. An LET-based relative biological effectiveness (RBE) model was used to evaluate the potential clinical benefit when navigating the space of Pareto-optimal BPs. Results: The mean LET values for the target varied up to 30% among the BPs for the head-and-neck patients and up to 14% for the pancreatic cancer patients. Variations were more prominent in organs at risk (OARs), where mean LET values differed by a factor of up to 2 among the BPs for the same patient. An inverse relation between dose and LET distributions for the OARs was typically observed. Accounting for LET-dependent variable RBE values, a potential improvement on RBE-weighted dose of up to 40%, averaged over several structures under study, was noticed during MCO navigation. Conclusions: We present a novel strategy for optimizing proton therapy to maximize dose-averaged LET in tumor targets while simultaneously minimizing dose-averaged LET in normal tissue structures. MCO BPs show substantial LET variations, leading to potentially significant differences in RBE-weighted doses. Pareto-surface navigation, using both dose and LET distributions for guidance, provides the means for evaluating a large variety of deliverable plans and aids in

  10. Linear Energy Transfer-Guided Optimization in Intensity Modulated Proton Therapy: Feasibility Study and Clinical Potential

    International Nuclear Information System (INIS)

    Giantsoudi, Drosoula; Grassberger, Clemens; Craft, David; Niemierko, Andrzej; Trofimov, Alexei; Paganetti, Harald

    2013-01-01

    Purpose: To investigate the feasibility and potential clinical benefit of linear energy transfer (LET) guided plan optimization in intensity modulated proton therapy (IMPT). Methods and Materials: A multicriteria optimization (MCO) module was used to generate a series of Pareto-optimal IMPT base plans (BPs), corresponding to defined objectives, for 5 patients with head-and-neck cancer and 2 with pancreatic cancer. A Monte Carlo platform was used to calculate dose and LET distributions for each BP. A custom-designed MCO navigation module allowed the user to interpolate between BPs to produce deliverable Pareto-optimal solutions. Differences among the BPs were evaluated for each patient, based on dose–volume and LET–volume histograms and 3-dimensional distributions. An LET-based relative biological effectiveness (RBE) model was used to evaluate the potential clinical benefit when navigating the space of Pareto-optimal BPs. Results: The mean LET values for the target varied up to 30% among the BPs for the head-and-neck patients and up to 14% for the pancreatic cancer patients. Variations were more prominent in organs at risk (OARs), where mean LET values differed by a factor of up to 2 among the BPs for the same patient. An inverse relation between dose and LET distributions for the OARs was typically observed. Accounting for LET-dependent variable RBE values, a potential improvement on RBE-weighted dose of up to 40%, averaged over several structures under study, was noticed during MCO navigation. Conclusions: We present a novel strategy for optimizing proton therapy to maximize dose-averaged LET in tumor targets while simultaneously minimizing dose-averaged LET in normal tissue structures. MCO BPs show substantial LET variations, leading to potentially significant differences in RBE-weighted doses. Pareto-surface navigation, using both dose and LET distributions for guidance, provides the means for evaluating a large variety of deliverable plans and aids in

  11. The Relationships between Weight Functions, Geometric Functions,and Compliance Functions in Linear Elastic Fracture Mechanics

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Rong [Univ. of California, Berkeley, CA (United States)

    2007-01-01

    Linear elastic fracture mechanics is widely used in industry because it established simple and explicit relationships between the permissible loading conditions and the critical crack size that is allowed in a structure. Stress intensity factors are the above-mentioned functional expressions that relate load with crack size through geometric functions or weight functions. Compliance functions are to determine the crack/flaw size in a structure when optical inspection is inconvenient. As a result, geometric functions, weight functions and compliance functions have been intensively studied to determine the stress intensity factor expressions for different geometries. However, the relations between these functions have received less attention. This work is therefore to investigate the intrinsic relationships between these functions. Theoretical derivation was carried out and the results were verified on single-edge cracked plate under tension and bending. It is found out that the geometric function is essentially the non-dimensional weight function at the loading point. The compliance function is composed of two parts: a varying part due to crack extension and a constant part from the intact structure if no crack exists. The derivative of the compliance function at any location is the product of the geometric function and the weight function at the evaluation point. Inversely, the compliance function can be acquired by the integration of the product of the geometric function and the weight function with respect to the crack size. The integral constant is just the unchanging compliance from the intact structure. Consequently, a special application of the relations is to obtain the compliance functions along a crack once the geometric function and weight functions are known. Any of the three special functions can be derived once the other two functions are known. These relations may greatly simplify the numerical process in obtaining either geometric functions, weight

  12. Linear combination of forecasts with numerical adjustment via MINIMAX non-linear programming

    Directory of Open Access Journals (Sweden)

    Jairo Marlon Corrêa

    2016-03-01

    Full Text Available This paper proposes a linear combination of forecasts obtained from three forecasting methods (namely, ARIMA, Exponential Smoothing and Artificial Neural Networks whose adaptive weights are determined via a multi-objective non-linear programming problem, which seeks to minimize, simultaneously, the statistics: MAE, MAPE and MSE. The results achieved by the proposed combination are compared with the traditional approach of linear combinations of forecasts, where the optimum adaptive weights are determined only by minimizing the MSE; with the combination method by arithmetic mean; and with individual methods

  13. Iterative Selection of Unknown Weights in Direct Weight Optimization Identification

    Directory of Open Access Journals (Sweden)

    Xiao Xuan

    2014-01-01

    Full Text Available To the direct weight optimization identification of the nonlinear system, we add some linear terms about input sequences in the former linear affine function so as to approximate the nonlinear property. To choose the two classes of unknown weights in the more linear terms, this paper derives the detailed process on how to choose these unknown weights from theoretical analysis and engineering practice, respectively, and makes sure of their key roles between the unknown weights. From the theoretical analysis, the added unknown weights’ auxiliary role can be known in the whole process of approximating the nonlinear system. From the practical analysis, we learn how to transform one complex optimization problem to its corresponding common quadratic program problem. Then, the common quadratic program problem can be solved by the basic interior point method. Finally, the efficiency and possibility of the proposed strategies can be confirmed by the simulation results.

  14. Prolificacy and Its Relationship with Age, Body Weight, Parity, Previous Litter Size and Body Linear Type Traits in Meat-type Goats

    Directory of Open Access Journals (Sweden)

    Avijit Haldar

    2014-05-01

    Full Text Available Data on age and body weight at breeding, parity, previous litter size, days open and some descriptive body linear traits from 389 meat-type, prolific Black Bengal goats in Tripura State of India, were collected for 3 and 1/2 years (2007 to 2010 and analyzed using logistic regression model. The objectives of the study were i to evaluate the effect of age and body weight at breeding, parity, previous litter size and days open on litter size of does; and ii to investigate if body linear type traits influenced litter size in meat-type, prolific goats. The incidence of 68.39% multiple births with a prolificacy rate of 175.07% was recorded. Higher age (>2.69 year, higher parity order (>2.31, more body weight at breeding (>20.5 kg and larger previous litter size (>1.65 showed an increase likelihood of multiple litter size when compared to single litter size. There was a strong, positive relationship between litter size and various body linear type traits like neck length (>22.78 cm, body length (>54.86 cm, withers height (>48.85 cm, croup height (>50.67 cm, distance between tuber coxae bones (>11.38 cm and distance between tuber ischii bones (>4.56 cm for discriminating the goats bearing multiple fetuses from those bearing a single fetus.

  15. Socially weighted linear composites in environmental decision making

    International Nuclear Information System (INIS)

    Hebert, J.A.; Lindell, M.K.; Maynard, W.S.; Nealey, S.M.; Burnham, J.B.

    1975-11-01

    A method for combining social values and technical information, for environmental decision making for the selection of a site for a nuclear power plant is described. Eight factors are identified by which six different thermal power plant site and design options could be evaluated. A method is described by which the factors could be weighted by social values and the weighted factor scores could be summed for each option. These weighted sums can then be compared with each other in order to determine the best choice from both a social and a technical point of view

  16. Non-linear second-order periodic systems with non-smooth potential

    Indian Academy of Sciences (India)

    In this paper we study second order non-linear periodic systems driven by the ordinary vector -Laplacian with a non-smooth, locally Lipschitz potential function. Our approach is variational and it is based on the non-smooth critical point theory. We prove existence and multiplicity results under general growth conditions on ...

  17. Non-linear second-order periodic systems with non-smooth potential

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    Abstract. In this paper we study second order non-linear periodic systems driven by the ordinary vector p-Laplacian with a non-smooth, locally Lipschitz potential function. Our approach is variational and it is based on the non-smooth critical point theory. We prove existence and multiplicity results under general growth ...

  18. On the existence of tunneling bounce solutions in piecewise linear potentials

    International Nuclear Information System (INIS)

    Dutta, Koushik; Hector, Cecelie; Konstandin, Thomas; Vaudrevange, Pascal M.; Westphal, Alexander

    2012-02-01

    Coleman tunneling in a general scalar potential with two non-degenerate minima is known to have an approximation in terms of a piecewise linear triangular-shaped potential with sharp 'kinks' at the place of the local minima. This approximate potential has a regime where the existence of the bounce solution needs the scalar field to 'wait' for some amount of Euclidean time at one of the 'kinks'. We discuss under which circumstances the correct bounce action can be consistently obtained as the limiting case of a regular scalar potential where 'kinks' are resolved as locally smooth 'cap' regions. (orig.)

  19. Hypocoercivity for linear kinetic equations conserving mass

    KAUST Repository

    Dolbeault, Jean; Mouhot, Clé ment; Schmeiser, Christian

    2015-01-01

    We develop a new method for proving hypocoercivity for a large class of linear kinetic equations with only one conservation law. Local mass conservation is assumed at the level of the collision kernel, while transport involves a confining potential, so that the solution relaxes towards a unique equilibrium state. Our goal is to evaluate in an appropriately weighted $ L^2$ norm the exponential rate of convergence to the equilibrium. The method covers various models, ranging from diffusive kinetic equations like Vlasov-Fokker-Planck equations, to scattering models or models with time relaxation collision kernels corresponding to polytropic Gibbs equilibria, including the case of the linear Boltzmann model. In this last case and in the case of Vlasov-Fokker-Planck equations, any linear or superlinear growth of the potential is allowed. - See more at: http://www.ams.org/journals/tran/2015-367-06/S0002-9947-2015-06012-7/#sthash.ChjyK6rc.dpuf

  20. Hypocoercivity for linear kinetic equations conserving mass

    KAUST Repository

    Dolbeault, Jean

    2015-02-03

    We develop a new method for proving hypocoercivity for a large class of linear kinetic equations with only one conservation law. Local mass conservation is assumed at the level of the collision kernel, while transport involves a confining potential, so that the solution relaxes towards a unique equilibrium state. Our goal is to evaluate in an appropriately weighted $ L^2$ norm the exponential rate of convergence to the equilibrium. The method covers various models, ranging from diffusive kinetic equations like Vlasov-Fokker-Planck equations, to scattering models or models with time relaxation collision kernels corresponding to polytropic Gibbs equilibria, including the case of the linear Boltzmann model. In this last case and in the case of Vlasov-Fokker-Planck equations, any linear or superlinear growth of the potential is allowed. - See more at: http://www.ams.org/journals/tran/2015-367-06/S0002-9947-2015-06012-7/#sthash.ChjyK6rc.dpuf

  1. Uncertainty of pesticide residue concentration determined from ordinary and weighted linear regression curve.

    Science.gov (United States)

    Yolci Omeroglu, Perihan; Ambrus, Árpad; Boyacioglu, Dilek

    2018-03-28

    Determination of pesticide residues is based on calibration curves constructed for each batch of analysis. Calibration standard solutions are prepared from a known amount of reference material at different concentration levels covering the concentration range of the analyte in the analysed samples. In the scope of this study, the applicability of both ordinary linear and weighted linear regression (OLR and WLR) for pesticide residue analysis was investigated. We used 782 multipoint calibration curves obtained for 72 different analytical batches with high-pressure liquid chromatography equipped with an ultraviolet detector, and gas chromatography with electron capture, nitrogen phosphorus or mass spectrophotometer detectors. Quality criteria of the linear curves including regression coefficient, standard deviation of relative residuals and deviation of back calculated concentrations were calculated both for WLR and OLR methods. Moreover, the relative uncertainty of the predicted analyte concentration was estimated for both methods. It was concluded that calibration curve based on WLR complies with all the quality criteria set by international guidelines compared to those calculated with OLR. It means that all the data fit well with WLR for pesticide residue analysis. It was estimated that, regardless of the actual concentration range of the calibration, relative uncertainty at the lowest calibrated level ranged between 0.3% and 113.7% for OLR and between 0.2% and 22.1% for WLR. At or above 1/3 of the calibrated range, uncertainty of calibration curve ranged between 0.1% and 16.3% for OLR and 0% and 12.2% for WLR, and therefore, the two methods gave comparable results.

  2. On the existence of tunneling bounce solutions in piecewise linear potentials

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, Koushik; Hector, Cecelie; Konstandin, Thomas; Vaudrevange, Pascal M.; Westphal, Alexander

    2012-02-15

    Coleman tunneling in a general scalar potential with two non-degenerate minima is known to have an approximation in terms of a piecewise linear triangular-shaped potential with sharp 'kinks' at the place of the local minima. This approximate potential has a regime where the existence of the bounce solution needs the scalar field to 'wait' for some amount of Euclidean time at one of the 'kinks'. We discuss under which circumstances the correct bounce action can be consistently obtained as the limiting case of a regular scalar potential where 'kinks' are resolved as locally smooth 'cap' regions. (orig.)

  3. Rainfall induced landslide susceptibility mapping using weight-of-evidence, linear and quadratic discriminant and logistic model tree method

    Science.gov (United States)

    Hong, H.; Zhu, A. X.

    2017-12-01

    Climate change is a common phenomenon and it is very serious all over the world. The intensification of rainfall extremes with climate change is of key importance to society and then it may induce a large impact through landslides. This paper presents GIS-based new ensemble data mining techniques that weight-of-evidence, logistic model tree, linear and quadratic discriminant for landslide spatial modelling. This research was applied in Anfu County, which is a landslide-prone area in Jiangxi Province, China. According to a literature review and research the study area, we select the landslide influencing factor and their maps were digitized in a GIS environment. These landslide influencing factors are the altitude, plan curvature, profile curvature, slope degree, slope aspect, topographic wetness index (TWI), Stream Power Index (SPI), Topographic Wetness Index (SPI), distance to faults, distance to rivers, distance to roads, soil, lithology, normalized difference vegetation index and land use. According to historical information of individual landslide events, interpretation of the aerial photographs, and field surveys supported by the government of Jiangxi Meteorological Bureau of China, 367 landslides were identified in the study area. The landslide locations were divided into two subsets, namely, training and validating (70/30), based on a random selection scheme. In this research, Pearson's correlation was used for the evaluation of the relationship between the landslides and influencing factors. In the next step, three data mining techniques combined with the weight-of-evidence, logistic model tree, linear and quadratic discriminant, were used for the landslide spatial modelling and its zonation. Finally, the landslide susceptibility maps produced by the mentioned models were evaluated by the ROC curve. The results showed that the area under the curve (AUC) of all of the models was > 0.80. At the same time, the highest AUC value was for the linear and quadratic

  4. On the exactness of the cavity method for weighted b-matchings on arbitrary graphs and its relation to linear programs

    International Nuclear Information System (INIS)

    Bayati, Mohsen; Borgs, Christian; Chayes, Jennifer; Zecchina, Riccardo

    2008-01-01

    We consider the general problem of finding the minimum weight b-matching on arbitrary graphs. We prove that, whenever the linear programing relaxation of the problem has no fractional solutions, then the cavity or belief propagation equations converge to the correct solution both for synchronous and asynchronous updating. (letter)

  5. Euclidean and Minkowski space formulations of linearized gravitational potential in various gauges

    International Nuclear Information System (INIS)

    Lim, S.C.

    1979-01-01

    We show that there exists a unitary map connecting linearized theories of gravitational potential in vacuum, formulated in various covariant gauges and noncovariant radiation gauge. The free Euclidean gravitational potentials in covariant gauges satisfy the Markov property of Nelson, but are nonreflexive. For the noncovariant radiation gauge, the corresponding Euclidean field is reflexive but it only satisfies the Markov property with respect to special half spaces. The Feynman--Kac--Nelson formula is established for the Euclidean gravitational potential in radiation gauge

  6. Linear inflation from quartic potential

    Energy Technology Data Exchange (ETDEWEB)

    Kannike, Kristjan; Racioppi, Antonio [National Institute of Chemical Physics and Biophysics,Rävala 10, 10143 Tallinn (Estonia); Raidal, Martti [National Institute of Chemical Physics and Biophysics,Rävala 10, 10143 Tallinn (Estonia); Institute of Physics, University of Tartu,Tartu (Estonia)

    2016-01-07

    We show that if the inflaton has a non-minimal coupling to gravity and the Planck scale is dynamically generated, the results of Coleman-Weinberg inflation are confined in between two attractor solutions: quadratic inflation, which is ruled out by the recent measurements, and linear inflation which, instead, is in the experimental allowed region. The minimal scenario has only one free parameter — the inflaton’s non-minimal coupling to gravity — that determines all physical parameters such as the tensor-to-scalar ratio and the reheating temperature of the Universe. Should the more precise future measurements of inflationary parameters point towards linear inflation, further interest in scale-invariant scenarios would be motivated.

  7. A method for determining optimum phasing of a multiphase propulsion system for a single-stage vehicle with linearized inert weight

    Science.gov (United States)

    Martin, J. A.

    1974-01-01

    A general analytical treatment is presented of a single-stage vehicle with multiple propulsion phases. A closed-form solution for the cost and for the performance and a derivation of the optimal phasing of the propulsion are included. Linearized variations in the inert weight elements are included, and the function to be minimized can be selected. The derivation of optimal phasing results in a set of nonlinear algebraic equations for optimal fuel volumes, for which a solution method is outlined. Three specific example cases are analyzed: minimum gross lift-off weight, minimum inert weight, and a minimized general function for a two-phase vehicle. The results for the two-phase vehicle are applied to the dual-fuel rocket. Comparisons with single-fuel vehicles indicate that dual-fuel vehicles can have lower inert weight either by development of a dual-fuel engine or by parallel burning of separate engines from lift-off.

  8. Application of hyperplane arrangements to weight enumeration

    NARCIS (Netherlands)

    Jurrius, R.P.M.J.; Pellikaan, G.R.

    2014-01-01

    Many research in coding theory is focussed on linear error-correcting codes. Since these codes are subspaces, linear algebra plays a prominent role in studying them. An important polynomial invariant of linear error-correcting codes is the (extended) weight enumerator. The weight enumerator gives

  9. Associations between maternal weekly air pollutant exposures and low birth weight: a distributed lag non-linear model

    Science.gov (United States)

    Wu, Han; Jiang, Baofa; Zhu, Ping; Geng, Xingyi; Liu, Zhong; Cui, Liangliang; Yang, Liping

    2018-02-01

    When discussing the association between birth weight and air pollution, previous studies mainly focus on the maternal trimester-specific exposures during pregnancy, whereas the possible associations between birth weight and weekly-specific exposures have been largely neglected. We conducted a nested 1:4 matched case-control study in Jinan, China to examine the weekly-specific associations during pregnancy between maternal fine particulate matter (aerodynamic diameter gender-, gestational age-, and parity-specific standard score (BWGAP z-score) was calculated as the outcome of interest. Distributed lag non-linear models (DLNMs) were applied to estimate weekly-specific relationship between maternal air pollutant exposures and birth weight. For an increase of per inter-quartile range in maternal PM2.5 exposure concentration during pregnancy, the BWGAP z-score decreased significantly during the 27th-33th gestational weeks with the strongest association in the 30th gestational weeks (standard deviation units decrease in BWGAP z-score: -0.049, 95% CI: -0.080 -0.017, in three-pollutant model). No significant association between maternal weekly NO2 or SO2 BWGAP z-score was observed. In conclusion, this study provides evidence that maternal PM2.5 exposure during the 27th-33th gestational weeks may reduce the birth weight in the context of very high pollution level of PM2.5.

  10. Universal equation for estimating ideal body weight and body weight at any BMI.

    Science.gov (United States)

    Peterson, Courtney M; Thomas, Diana M; Blackburn, George L; Heymsfield, Steven B

    2016-05-01

    Ideal body weight (IBW) equations and body mass index (BMI) ranges have both been used to delineate healthy or normal weight ranges, although these 2 different approaches are at odds with each other. In particular, past IBW equations are misaligned with BMI values, and unlike BMI, the equations have failed to recognize that there is a range of ideal or target body weights. For the first time, to our knowledge, we merged the concepts of a linear IBW equation and of defining target body weights in terms of BMI. With the use of calculus and approximations, we derived an easy-to-use linear equation that clinicians can use to calculate both IBW and body weight at any target BMI value. We measured the empirical accuracy of the equation with the use of NHANES data and performed a comparative analysis with past IBW equations. Our linear equation allowed us to calculate body weights for any BMI and height with a mean empirical accuracy of 0.5-0.7% on the basis of NHANES data. Moreover, we showed that our body weight equation directly aligns with BMI values for both men and women, which avoids the overestimation and underestimation problems at the upper and lower ends of the height spectrum that have plagued past IBW equations. Our linear equation increases the sophistication of IBW equations by replacing them with a single universal equation that calculates both IBW and body weight at any target BMI and height. Therefore, our equation is compatible with BMI and can be applied with the use of mental math or a calculator without the need for an app, which makes it a useful tool for both health practitioners and the general public. © 2016 American Society for Nutrition.

  11. A novel large thrust-weight ratio V-shaped linear ultrasonic motor with a flexible joint.

    Science.gov (United States)

    Li, Xiaoniu; Yao, Zhiyuan; Yang, Mojian

    2017-06-01

    A novel large thrust-weight ratio V-shaped linear ultrasonic motor with a flexible joint is proposed in this paper. The motor is comprised of a V-shaped transducer, a slider, a clamp, and a base. The V-shaped transducer consists of two piezoelectric beams connected through a flexible joint to form an appropriate coupling angle. The V-shaped motor is operated in the coupled longitudinal-bending mode. Longitudinal and bending movements are transferred by the flexible joint between the two beams. Compared with the coupled longitudinal-bending mode of the single piezoelectric beam or the symmetrical and asymmetrical modes of the previous V-shaped transducer, the coupled longitudinal-bending mode of the V-shaped transducer with a flexible joint provides higher vibration efficiency and more convenient mode conformance adjustment. A finite element model of the V-shaped transducer is created to numerically study the influence of geometrical parameters and to determine the final geometrical parameters. In this paper, three prototypes were then fabricated and experimentally investigated. The modal test results match well with the finite element analysis. The motor mechanical output characteristics of three different coupling angles θ indicate that V-90 (θ = 90°) is the optimal angle. The mechanical output experiments conducted using the V-90 prototype (Size: 59.4 mm × 30.7 mm × 4 mm) demonstrate that the maximum unloaded speed is 1.2 m/s under a voltage of 350 Vpp, and the maximum output force is 15 N under a voltage of 300 Vpp. The proposed novel V-shaped linear ultrasonic motor has a compact size and a simple structure with a large thrust-weight ratio (0.75 N/g) and high speed.

  12. Closed-form solutions for linear regulator-design of mechanical systems including optimal weighting matrix selection

    Science.gov (United States)

    Hanks, Brantley R.; Skelton, Robert E.

    1991-01-01

    This paper addresses the restriction of Linear Quadratic Regulator (LQR) solutions to the algebraic Riccati Equation to design spaces which can be implemented as passive structural members and/or dampers. A general closed-form solution to the optimal free-decay control problem is presented which is tailored for structural-mechanical systems. The solution includes, as subsets, special cases such as the Rayleigh Dissipation Function and total energy. Weighting matrix selection is a constrained choice among several parameters to obtain desired physical relationships. The closed-form solution is also applicable to active control design for systems where perfect, collocated actuator-sensor pairs exist. Some examples of simple spring mass systems are shown to illustrate key points.

  13. The maximally achievable accuracy of linear optimal regulators and linear optimal filters

    NARCIS (Netherlands)

    Kwakernaak, H.; Sivan, Raphael

    1972-01-01

    A linear system with a quadratic cost function, which is a weighted sum of the integral square regulation error and the integral square input, is considered. What happens to the integral square regulation error as the relative weight of the integral square input reduces to zero is investigated. In

  14. The potential in general linear electrodynamics. Causal structure, propagators and quantization

    Energy Technology Data Exchange (ETDEWEB)

    Siemssen, Daniel [Department of Mathematical Methods in Physics, Faculty of Physics, University of Warsaw (Poland); Pfeifer, Christian [Institute for Theoretical Physics, Leibniz Universitaet Hannover (Germany); Center of Applied Space Technology and Microgravity (ZARM), Universitaet Bremen (Germany)

    2016-07-01

    From an axiomatic point of view, the fundamental input for a theory of electrodynamics are Maxwell's equations dF=0 (or F=dA) and dH=J, and a constitutive law H=F, which relates the field strength 2-form F and the excitation 2-form H. In this talk we consider general linear electrodynamics, the theory of electrodynamics defined by a linear constitutive law. The best known application of this theory is the effective description of electrodynamics inside (linear) media (e.g. birefringence). We analyze the classical theory of the electromagnetic potential A before we use methods familiar from mathematical quantum field theory in curved spacetimes to quantize it. Our analysis of the classical theory contains the derivation of retarded and advanced propagators, the analysis of the causal structure on the basis of the constitutive law (instead of a metric) and a discussion of the classical phase space. This classical analysis sets the stage for the construction of the quantum field algebra and quantum states, including a (generalized) microlocal spectrum condition.

  15. Weighted A-statistical convergence for sequences of positive linear operators.

    Science.gov (United States)

    Mohiuddine, S A; Alotaibi, Abdullah; Hazarika, Bipan

    2014-01-01

    We introduce the notion of weighted A-statistical convergence of a sequence, where A represents the nonnegative regular matrix. We also prove the Korovkin approximation theorem by using the notion of weighted A-statistical convergence. Further, we give a rate of weighted A-statistical convergence and apply the classical Bernstein polynomial to construct an illustrative example in support of our result.

  16. Healthy weight and lifestyle advertisements: an assessment of their persuasive potential.

    Science.gov (United States)

    Dixon, Helen; Scully, Maree; Cotter, Trish; Maloney, Sarah; Wakefield, Melanie

    2015-08-01

    This study aimed to identify and analyse the content of previously produced and aired adult-targeted public health advertisements (ads) addressing weight, nutrition or physical activity internationally. Ads were identified via keyword searches of Google, YouTube and websites of relevant government agencies and health organizations, and were eligible for inclusion if they were: in English; produced between 2007 and 2012; targeted at adults; ≤60 s; not promoting a particular commercial brand of food, fitness or weight loss product. Of the 99 ads coded, 59% featured supportive/encouraging messages, 36% presented information about health consequences and 17% focussed on social norms/acceptability issues. Supportive/encouraging messages were more frequently used in physical activity ads, while there were a higher proportion of messages about health consequences in weight ads. Execution style differed across lifestyle topics, with simulation/animation more common in nutrition ads and graphic images and negative personal testimonials in weight ads. Ads addressing weight were more likely to evoke high negative emotion and include potentially stigmatizing content. Understanding how weight and lifestyle issues have been addressed in recent public health advertising will help guide future efforts to test the effectiveness of different message types in facilitating positive behaviour changes. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  17. Biochemical methane potential prediction of plant biomasses: Comparing chemical composition versus near infrared methods and linear versus non-linear models.

    Science.gov (United States)

    Godin, Bruno; Mayer, Frédéric; Agneessens, Richard; Gerin, Patrick; Dardenne, Pierre; Delfosse, Philippe; Delcarte, Jérôme

    2015-01-01

    The reliability of different models to predict the biochemical methane potential (BMP) of various plant biomasses using a multispecies dataset was compared. The most reliable prediction models of the BMP were those based on the near infrared (NIR) spectrum compared to those based on the chemical composition. The NIR predictions of local (specific regression and non-linear) models were able to estimate quantitatively, rapidly, cheaply and easily the BMP. Such a model could be further used for biomethanation plant management and optimization. The predictions of non-linear models were more reliable compared to those of linear models. The presentation form (green-dried, silage-dried and silage-wet form) of biomasses to the NIR spectrometer did not influence the performances of the NIR prediction models. The accuracy of the BMP method should be improved to enhance further the BMP prediction models. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Point charge potential and weighting field of a pixel or pad in a plane condenser

    Energy Technology Data Exchange (ETDEWEB)

    Riegler, W.; Aglieri Rinella, G.

    2014-12-11

    We derive expressions for the potential of a point charge as well as the weighting potential and weighting field of a rectangular pad for a plane condenser, which are well suited for numerical evaluation. We relate the expressions to solutions employing the method of image charges, which allows discussion of convergence properties and estimation of errors, providing also an illuminating example of a problem with an infinite number of image charges.

  19. Weighted A-Statistical Convergence for Sequences of Positive Linear Operators

    Directory of Open Access Journals (Sweden)

    S. A. Mohiuddine

    2014-01-01

    Full Text Available We introduce the notion of weighted A-statistical convergence of a sequence, where A represents the nonnegative regular matrix. We also prove the Korovkin approximation theorem by using the notion of weighted A-statistical convergence. Further, we give a rate of weighted A-statistical convergence and apply the classical Bernstein polynomial to construct an illustrative example in support of our result.

  20. Common SAR Derived from Linear and Non-linear QSAR Studies on AChE Inhibitors used in the Treatment of Alzheimer's Disease.

    Science.gov (United States)

    Pulikkal, Babitha Pallikkara; Marunnan, Sahila Mohammed; Bandaru, Srinivas; Yadav, Mukesh; Nayarisseri, Anuraj; Sureshkumar, Sivanpillai

    2017-11-14

    Deficits in cholinergic neurotransmission due to the degeneration of cholinergic neurons in the brain are believed to be one of the major causes of the memory impairments associated with AD. Targeting acetyl cholinesterase (AChE) surfaced as a potential therapeutic target in the treatment of Alzheimer's disease. The present study is pursued to develop quantitative structure activity relationship (QSAR) models to determine chemical descriptors responsible for AChE activity. Two different sets of AChE inhibitors, dataset-I (30 compounds) and dataset-II (20 compounds) were investigated through MLR aided linear and SVM aided non-linear QSAR models. The obtained QSAR models were found statistically fit, stable and predictive on validation scales. These QSAR models were further investigated for their common structure-activity relationship in terms of overlapping molecular descriptors selection. Atomic mass weighted 3D Morse descriptors (MATS5m) and Radial Distribution Function (RDF045m) descriptors were found in common SAR for both the datasets. Electronegativity weighted (MATS5e, HATSe, and Mor17e) descriptors have also been identified in regulative roles towards endpoint values of dataset-I and dataset-II. The common SAR identified in these linear and non-linear QSAR models could be utilized to design novel inhibitors of AChE with improved biological activity. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  1. An implicit spectral formula for generalized linear Schroedinger equations

    International Nuclear Information System (INIS)

    Schulze-Halberg, A.; Garcia-Ravelo, J.; Pena Gil, Jose Juan

    2009-01-01

    We generalize the semiclassical Bohr–Sommerfeld quantization rule to an exact, implicit spectral formula for linear, generalized Schroedinger equations admitting a discrete spectrum. Special cases include the position-dependent mass Schroedinger equation or the Schroedinger equation for weighted energy. Requiring knowledge of the potential and the solution associated with the lowest spectral value, our formula predicts the complete spectrum in its exact form. (author)

  2. Preterm infant linear growth and adiposity gain: trade-offs for later weight status and intelligence quotient.

    Science.gov (United States)

    Belfort, Mandy B; Gillman, Matthew W; Buka, Stephen L; Casey, Patrick H; McCormick, Marie C

    2013-12-01

    To examine trade-offs between cognitive outcome and overweight/obesity in preterm-born infants at school age and young adulthood in relation to weight gain and linear growth during infancy. We studied 945 participants in the Infant Health and Development Program, an 8-center study of preterm (≤37 weeks gestational age), low birth weight (≤2500 g) infants from birth to age 18 years. Adjusting for maternal and child factors in logistic regression, we estimated the odds of overweight/obesity (body mass index [BMI] ≥85th percentile at age 8 or ≥25 kg/m(2) at age 18) and in separate models, low IQ (growth from term to 4 months was associated with lower odds of IQ growth soon after term was associated with better cognition, but also with a greater risk of overweight/obesity at age 8 years and 18 years. BMI gain over the entire 18 months after term was associated with later risk of overweight/obesity, with less evidence of a benefit for IQ. Copyright © 2013 Mosby, Inc. All rights reserved.

  3. Mean-Variance-CvaR Model of Multiportfolio Optimization via Linear Weighted Sum Method

    Directory of Open Access Journals (Sweden)

    Younes Elahi

    2014-01-01

    Full Text Available We propose a new approach to optimizing portfolios to mean-variance-CVaR (MVC model. Although of several researches have studied the optimal MVC model of portfolio, the linear weighted sum method (LWSM was not implemented in the area. The aim of this paper is to investigate the optimal portfolio model based on MVC via LWSM. With this method, the solution of the MVC model of portfolio as the multiobjective problem is presented. In data analysis section, this approach in investing on two assets is investigated. An MVC model of the multiportfolio was implemented in MATLAB and tested on the presented problem. It is shown that, by using three objective functions, it helps the investors to manage their portfolio better and thereby minimize the risk and maximize the return of the portfolio. The main goal of this study is to modify the current models and simplify it by using LWSM to obtain better results.

  4. Glucagon-like peptide-1 analogs against antipsychotic-induced weight gain: potential physiological benefits

    Science.gov (United States)

    2012-01-01

    Background Antipsychotic-induced weight gain constitutes a major unresolved clinical problem which may ultimately be associated with reducing life expectancy by 25 years. Overweight is associated with brain deterioration, cognitive decline and poor quality of life, factors which are already compromised in normal weight patients with schizophrenia. Here we outline the current strategies against antipsychotic-induced weight gain, and we describe peripheral and cerebral effects of the gut hormone glucagon-like peptide-1 (GLP-1). Moreover, we account for similarities in brain changes between schizophrenia and overweight patients. Discussion Current interventions against antipsychotic-induced weight gain do not facilitate a substantial and lasting weight loss. GLP-1 analogs used in the treatment of type 2 diabetes are associated with significant and sustained weight loss in overweight patients. Potential effects of treating schizophrenia patients with antipsychotic-induced weight gain with GLP-1 analogs are discussed. Conclusions We propose that adjunctive treatment with GLP-1 analogs may constitute a new avenue to treat and prevent metabolic and cerebral deficiencies in schizophrenia patients with antipsychotic-induced weight gain. Clinical research to support this idea is highly warranted. PMID:22891821

  5. Glucagon-like peptide-1 analogs against antipsychotic-induced weight gain: potential physiological benefits

    Directory of Open Access Journals (Sweden)

    Ebdrup Bjørn H

    2012-08-01

    Full Text Available Abstract Background Antipsychotic-induced weight gain constitutes a major unresolved clinical problem which may ultimately be associated with reducing life expectancy by 25 years. Overweight is associated with brain deterioration, cognitive decline and poor quality of life, factors which are already compromised in normal weight patients with schizophrenia. Here we outline the current strategies against antipsychotic-induced weight gain, and we describe peripheral and cerebral effects of the gut hormone glucagon-like peptide-1 (GLP-1. Moreover, we account for similarities in brain changes between schizophrenia and overweight patients. Discussion Current interventions against antipsychotic-induced weight gain do not facilitate a substantial and lasting weight loss. GLP-1 analogs used in the treatment of type 2 diabetes are associated with significant and sustained weight loss in overweight patients. Potential effects of treating schizophrenia patients with antipsychotic-induced weight gain with GLP-1 analogs are discussed. Conclusions We propose that adjunctive treatment with GLP-1 analogs may constitute a new avenue to treat and prevent metabolic and cerebral deficiencies in schizophrenia patients with antipsychotic-induced weight gain. Clinical research to support this idea is highly warranted.

  6. ESTIMATION OF YELLOWFIN TUNA PRODUCTION LANDED IN BENOA PORT WITH WEIGHT-WEIGHT, LENGTH-WEIGHT RELATIONSHIPS AND CONDITION FACTOR APPROACHES

    Directory of Open Access Journals (Sweden)

    Irwan Jatmiko

    2017-01-01

    Full Text Available Yellowfin tuna (Thunnus albacares is one of the important catch for the fishing industry in Indonesia. Length-weight relationship study is one of important tools to support fisheries management. However it could not be done to yellowfin tuna landed in Benoa port since they are in the form of gilled-gutted condition. The objectives of this study are to determine the relationship between gilled-gutted weight (GW and whole weight (WW, to calculate length weight relationship between fork length (FL and estimated whole weight (WW and to assess the relative condition factor (Kn of yellowfin tuna in Eastern Indian Ocean. Data were collected from three landing sites i.e. Malang, East Java; Benoa, Bali and Kupang, East Nusa Tenggara from January 2013 to February 2014. Linear regression analysis applied to test the significance baseline between weight-weight relationships and log transformed length weight relationship. Relative condition factor (Kn used to identify fish condition among length groups and months. The results showed a significant positive linear relationships between whole weight (WW and gilled-gutted weight (GW of T. albacares (p<0.001. There was a significant positive linier relationships between log transformed fork length and log transformed whole weight of T. albacares (p<0.001. Relative condition factor (Kn showed declining pattern along with length increase and varied among months. The findings from this study provide data for management of yellowfin tuna stock and population.

  7. Modeling Fire Occurrence at the City Scale: A Comparison between Geographically Weighted Regression and Global Linear Regression.

    Science.gov (United States)

    Song, Chao; Kwan, Mei-Po; Zhu, Jiping

    2017-04-08

    An increasing number of fires are occurring with the rapid development of cities, resulting in increased risk for human beings and the environment. This study compares geographically weighted regression-based models, including geographically weighted regression (GWR) and geographically and temporally weighted regression (GTWR), which integrates spatial and temporal effects and global linear regression models (LM) for modeling fire risk at the city scale. The results show that the road density and the spatial distribution of enterprises have the strongest influences on fire risk, which implies that we should focus on areas where roads and enterprises are densely clustered. In addition, locations with a large number of enterprises have fewer fire ignition records, probably because of strict management and prevention measures. A changing number of significant variables across space indicate that heterogeneity mainly exists in the northern and eastern rural and suburban areas of Hefei city, where human-related facilities or road construction are only clustered in the city sub-centers. GTWR can capture small changes in the spatiotemporal heterogeneity of the variables while GWR and LM cannot. An approach that integrates space and time enables us to better understand the dynamic changes in fire risk. Thus governments can use the results to manage fire safety at the city scale.

  8. Association between body weight and dimensional shell traits of ...

    African Journals Online (AJOL)

    The results of regression models revealed that live weight of A. achatina was best predicted with multiple linear regression models, while with live weight of A. marginata was best predicted with simple linear regression model and multiple linear regression models. A test of accuracy of the linear regression models showed ...

  9. Stochastic quantum inflation for a canonical scalar field with linear self-interaction potential

    Energy Technology Data Exchange (ETDEWEB)

    Panotopoulos, Grigoris [CENTRA, Instituto Superior Tecnico, Universidade de Lisboa, Lisboa (Portugal)

    2017-10-15

    We apply Starobinsky's formalism of stochastic inflation to the case of a massless minimally coupled scalar field with linear self-interaction potential. We solve the corresponding Fokker-Planck equation exactly, and we obtain analytical expressions for the stochastic expectation values. (orig.)

  10. Linear estimation discriminates midline sources and motor cortex contribution to the readiness potential

    NARCIS (Netherlands)

    Knosche, Thomas; Knosche, T.R.; Praamstra, Peter; Peters, M.J.; Stegeman, Dick; Stegeman, D.

    1996-01-01

    Spatiotemporal dipole modelling of the generators of the readiness potential (RP) prior to voluntary movements has yielded diverging results concerning the contributions of supplementary motor area (SMA) and primary motor cortex. We applied an alternative approach (i.e. linear estimation theory) to

  11. Weight of evidence analysis for assessing the genotoxic potential of carbon nanotubes

    DEFF Research Database (Denmark)

    Møller, Peter; Jacobsen, Nicklas Raun

    2017-01-01

    Carbon nanotube (CNT) is a nanomaterial that has received interest because of its high-tensile strength and low weight. Although CNTs differ substantially in physico-chemical properties, they share high aspect ratio which resembles that of asbestos and other fibers causing lung cancer...... and insufficient mechanistic evidence. Damage to DNA is considered to be a key mechanistic step in the development of fiber-induced cancer. Thus, the genotoxic potential can be a cornerstone in the evaluation of hazards of CNTs. The present study used a weight of evidence (WoE) analysis to evaluate...

  12. Controllable excitation of higher-order rogue waves in nonautonomous systems with both varying linear and harmonic external potentials

    Science.gov (United States)

    Jia, Heping; Yang, Rongcao; Tian, Jinping; Zhang, Wenmei

    2018-05-01

    The nonautonomous nonlinear Schrödinger (NLS) equation with both varying linear and harmonic external potentials is investigated and the semirational rogue wave (RW) solution is presented by similarity transformation. Based on the solution, the interactions between Peregrine soliton and breathers, and the controllability of the semirational RWs in periodic distribution and exponential decreasing nonautonomous systems with both linear and harmonic potentials are studied. It is found that the harmonic potential only influences the constraint condition of the semirational solution, the linear potential is related to the trajectory of the semirational RWs, while dispersion and nonlinearity determine the excitation position of the higher-order RWs. The higher-order RWs can be partly, completely and biperiodically excited in periodic distribution system and the diverse excited patterns can be generated for different parameter relations in exponential decreasing system. The results reveal that the excitation of the higher-order RWs can be controlled in the nonautonomous system by choosing dispersion, nonlinearity and external potentials.

  13. Statistically-Efficient Filtering in Impulsive Environments: Weighted Myriad Filters

    Directory of Open Access Journals (Sweden)

    Juan G. Gonzalez

    2002-01-01

    Full Text Available Linear filtering theory has been largely motivated by the characteristics of Gaussian signals. In the same manner, the proposed Myriad Filtering methods are motivated by the need for a flexible filter class with high statistical efficiency in non-Gaussian impulsive environments that can appear in practice. Myriad filters have a solid theoretical basis, are inherently more powerful than median filters, and are very general, subsuming traditional linear FIR filters. The foundation of the proposed filtering algorithms lies in the definition of the myriad as a tunable estimator of location derived from the theory of robust statistics. We prove several fundamental properties of this estimator and show its optimality in practical impulsive models such as the α-stable and generalized-t. We then extend the myriad estimation framework to allow the use of weights. In the same way as linear FIR filters become a powerful generalization of the mean filter, filters based on running myriads reach all of their potential when a weighting scheme is utilized. We derive the “normal” equations for the optimal myriad filter, and introduce a suboptimal methodology for filter tuning and design. The strong potential of myriad filtering and estimation in impulsive environments is illustrated with several examples.

  14. Successive 1-Month Weight Increments in Infancy Can Be Used to Screen for Faltering Linear Growth.

    Science.gov (United States)

    Onyango, Adelheid W; Borghi, Elaine; de Onis, Mercedes; Frongillo, Edward A; Victora, Cesar G; Dewey, Kathryn G; Lartey, Anna; Bhandari, Nita; Baerug, Anne; Garza, Cutberto

    2015-12-01

    Linear growth faltering in the first 2 y contributes greatly to a high stunting burden, and prevention is hampered by the limited capacity in primary health care for timely screening and intervention. This study aimed to determine an approach to predicting long-term stunting from consecutive 1-mo weight increments in the first year of life. By using the reference sample of the WHO velocity standards, the analysis explored patterns of consecutive monthly weight increments among healthy infants. Four candidate screening thresholds of successive increments that could predict stunting were considered, and one was selected for further testing. The selected threshold was applied in a cohort of Bangladeshi infants to assess its predictive value for stunting at ages 12 and 24 mo. Between birth and age 12 mo, 72.6% of infants in the WHO sample tracked within 1 SD of their weight and length. The selected screening criterion ("event") was 2 consecutive monthly increments below the 15th percentile. Bangladeshi infants were born relatively small and, on average, tracked downward from approximately age 6 to strategy is effective, the estimated preventable proportion in the group who experienced the event would be 34% at 12 mo and 24% at 24 mo. This analysis offers an approach for frontline workers to identify children at risk of stunting, allowing for timely initiation of preventive measures. It opens avenues for further investigation into evidence-informed application of the WHO growth velocity standards. © 2015 American Society for Nutrition.

  15. Least median of squares and iteratively re-weighted least squares as robust linear regression methods for fluorimetric determination of α-lipoic acid in capsules in ideal and non-ideal cases of linearity.

    Science.gov (United States)

    Korany, Mohamed A; Gazy, Azza A; Khamis, Essam F; Ragab, Marwa A A; Kamal, Miranda F

    2018-03-26

    This study outlines two robust regression approaches, namely least median of squares (LMS) and iteratively re-weighted least squares (IRLS) to investigate their application in instrument analysis of nutraceuticals (that is, fluorescence quenching of merbromin reagent upon lipoic acid addition). These robust regression methods were used to calculate calibration data from the fluorescence quenching reaction (∆F and F-ratio) under ideal or non-ideal linearity conditions. For each condition, data were treated using three regression fittings: Ordinary Least Squares (OLS), LMS and IRLS. Assessment of linearity, limits of detection (LOD) and quantitation (LOQ), accuracy and precision were carefully studied for each condition. LMS and IRLS regression line fittings showed significant improvement in correlation coefficients and all regression parameters for both methods and both conditions. In the ideal linearity condition, the intercept and slope changed insignificantly, but a dramatic change was observed for the non-ideal condition and linearity intercept. Under both linearity conditions, LOD and LOQ values after the robust regression line fitting of data were lower than those obtained before data treatment. The results obtained after statistical treatment indicated that the linearity ranges for drug determination could be expanded to lower limits of quantitation by enhancing the regression equation parameters after data treatment. Analysis results for lipoic acid in capsules, using both fluorimetric methods, treated by parametric OLS and after treatment by robust LMS and IRLS were compared for both linearity conditions. Copyright © 2018 John Wiley & Sons, Ltd.

  16. Analysis of infant cry through weighted linear prediction cepstral coefficients and Probabilistic Neural Network.

    Science.gov (United States)

    Hariharan, M; Chee, Lim Sin; Yaacob, Sazali

    2012-06-01

    Acoustic analysis of infant cry signals has been proven to be an excellent tool in the area of automatic detection of pathological status of an infant. This paper investigates the application of parameter weighting for linear prediction cepstral coefficients (LPCCs) to provide the robust representation of infant cry signals. Three classes of infant cry signals were considered such as normal cry signals, cry signals from deaf babies and babies with asphyxia. A Probabilistic Neural Network (PNN) is suggested to classify the infant cry signals into normal and pathological cries. PNN is trained with different spread factor or smoothing parameter to obtain better classification accuracy. The experimental results demonstrate that the suggested features and classification algorithms give very promising classification accuracy of above 98% and it expounds that the suggested method can be used to help medical professionals for diagnosing pathological status of an infant from cry signals.

  17. A linear-quadratic model of cell survival considering both sublethal and potentially lethal radiation damage

    International Nuclear Information System (INIS)

    Rutz, H.P.; Coucke, P.A.; Mirimanoff, R.O.

    1991-01-01

    The authors assessed the dose-dependence of repair of potentially lethal damage in Chinese hamster ovary cells x-irradiated in vitro. The recovery ratio (RR) by which survival (SF) of the irradiated cells was enhanced increased exponentially with a linear and a quadratic component namely ζ and ψ: RR=exp(ζD+ψD 2 ). Survival of irradiated cells can thus be expressed by a combined linear-quadratic model considering 4 variables, namely α and β for the capacity of the cells to accumulate sublethal damage, and ζ and ψ for their capacity to repair potentially lethal damage: SF=exp((ζ-α)D+ (ψ-β)D 2 ). author. 26 refs.; 1 fig.; 1 tab

  18. From neurons to circuits: linear estimation of local field potentials

    Science.gov (United States)

    Rasch, Malte; Logthetis, Nikos K.; Kreiman, Gabriel

    2010-01-01

    Extracellular physiological recordings are typically separated into two frequency bands: local field potentials (LFPs, a circuit property) and spiking multi-unit activity (MUA). There has been increased interest in LFPs due to their correlation with fMRI measurements and the possibility of studying local processing and neuronal synchrony. To further understand the biophysical origin of LFPs, we asked whether it is possible to estimate their time course based on the spiking activity from the same or nearby electrodes. We used Signal Estimation Theory to show that a linear filter operation on the activity of one/few neurons can explain a significant fraction of the LFP time course in the macaque primary visual cortex. The linear filter used to estimate the LFPs had a stereotypical shape characterized by a sharp downstroke at negative time lags and a slower positive upstroke for positve time lags. The filter was similar across neocortical regions and behavioral conditions including spontaneous activity and visual stimulation. The estimations had a spatial resolution of ~1 mm and a temporal resolution of ~200 ms. By considering a causal filter, we observed a temporal asymmetry such that the positive time lags in the filter contributed more to the LFP estimation than negative time lags. Additionally, we showed that spikes occurring within ~10 ms of spikes from nearby neurons yielded better estimation accuracies than nonsynchronous spikes. In sum, our results suggest that at least some circuit-level local properties of the field potentials can be predicted from the activity of one or a few neurons. PMID:19889990

  19. Linear mixed-effects models to describe length-weight relationships for yellow croaker (Larimichthys Polyactis) along the north coast of China.

    Science.gov (United States)

    Ma, Qiuyun; Jiao, Yan; Ren, Yiping

    2017-01-01

    In this study, length-weight relationships and relative condition factors were analyzed for Yellow Croaker (Larimichthys polyactis) along the north coast of China. Data covered six regions from north to south: Yellow River Estuary, Coastal Waters of Northern Shandong, Jiaozhou Bay, Coastal Waters of Qingdao, Haizhou Bay, and South Yellow Sea. In total 3,275 individuals were collected during six years (2008, 2011-2015). One generalized linear model, two simply linear models and nine linear mixed effect models that applied the effects from regions and/or years to coefficient a and/or the exponent b were studied and compared. Among these twelve models, the linear mixed effect model with random effects from both regions and years fit the data best, with lowest Akaike information criterion value and mean absolute error. In this model, the estimated a was 0.0192, with 95% confidence interval 0.0178~0.0308, and the estimated exponent b was 2.917 with 95% confidence interval 2.731~2.945. Estimates for a and b with the random effects in intercept and coefficient from Region and Year, ranged from 0.013 to 0.023 and from 2.835 to 3.017, respectively. Both regions and years had effects on parameters a and b, while the effects from years were shown to be much larger than those from regions. Except for Coastal Waters of Northern Shandong, a decreased from north to south. Condition factors relative to reference years of 1960, 1986, 2005, 2007, 2008~2009 and 2010 revealed that the body shape of Yellow Croaker became thinner in recent years. Furthermore relative condition factors varied among months, years, regions and length. The values of a and relative condition factors decreased, when the environmental pollution became worse, therefore, length-weight relationships could be an indicator for the environment quality. Results from this study provided basic description of current condition of Yellow Croaker along the north coast of China.

  20. Elevated plasma urokinase receptor predicts low birth weight in maternal malaria

    DEFF Research Database (Denmark)

    Ostrowski, S R; Shulman, C E; Peshu, N

    2007-01-01

    -suPAR and gestational age were the only independent predictors of birth weight in multivariate linear regression adjusted for maternal-suPAR, HIV-1 infection, age, BMI, haemoglobin, peripheral parasitaemia, parity and gestational age; 1 ng/mL higher maternal-suPAR predicted -56 g (95% CI -100 to -12, P = 0.016) reduced...... birth weight. Cord-suPAR could not predict birth weight after adjusting for gestational age. Future studies are warranted to investigate whether the maternal suPAR level is increased earlier in pregnancy in women with active placental malaria infection and whether early maternal suPAR measurements can...... predict birth weight. If so, measurements of maternal suPAR early in pregnancy might then potentially identify women with increased needs for antenatal care and intervention....

  1. SYMMETRY PROPERTIES OF THE COULOMB POTENTIAL WITH A LINEAR DEPENDENCE ON ENERGY

    Directory of Open Access Journals (Sweden)

    Radu Budaca

    2017-12-01

    Full Text Available The D-dimensional Schr ̈odinger equation for a Coulomb potential with a coupling constant depending linearly on energy is analytically solved. The energy spectrum in the asymptotic regime of the slope parameter is found to be fully determined up to a scale only by its quantum numbers. The raising and lowering operators for this limiting model are determined from the recurrence properties of the associated solutions. It is shown that they satisfy the commutation relations of an SU(1,1 algebra and act on wave-functions which are normalized differently from the case of the usual bound state problem for an energy independent Coulomb potential.

  2. Ensemble Weight Enumerators for Protograph LDPC Codes

    Science.gov (United States)

    Divsalar, Dariush

    2006-01-01

    Recently LDPC codes with projected graph, or protograph structures have been proposed. In this paper, finite length ensemble weight enumerators for LDPC codes with protograph structures are obtained. Asymptotic results are derived as the block size goes to infinity. In particular we are interested in obtaining ensemble average weight enumerators for protograph LDPC codes which have minimum distance that grows linearly with block size. As with irregular ensembles, linear minimum distance property is sensitive to the proportion of degree-2 variable nodes. In this paper the derived results on ensemble weight enumerators show that linear minimum distance condition on degree distribution of unstructured irregular LDPC codes is a sufficient but not a necessary condition for protograph LDPC codes.

  3. Compact solitary waves in linearly elastic chains with non-smooth on-site potential

    Energy Technology Data Exchange (ETDEWEB)

    Gaeta, Giuseppe [Dipartimento di Matematica, Universita di Milano, Via Saldini 50, 20133 Milan (Italy); Gramchev, Todor [Dipartimento di Matematica e Informatica, Universita di Cagliari, Via Ospedale 72, 09124 Cagliari (Italy); Walcher, Sebastian [Lehrstuhl A Mathematik, RWTH Aachen, 52056 Aachen (Germany)

    2007-04-27

    It was recently observed by Saccomandi and Sgura that one-dimensional chains with nonlinear elastic interaction and regular on-site potential can support compact solitary waves, i.e. travelling solitary waves with strictly compact support. In this paper, we show that the same applies to chains with linear elastic interaction and an on-site potential which is continuous but non-smooth at minima. Some different features arise; in particular, the speed of compact solitary waves is not uniquely fixed by the equation. We also discuss several generalizations of our findings.

  4. Quantitative Pointwise Estimate of the Solution of the Linearized Boltzmann Equation

    Science.gov (United States)

    Lin, Yu-Chu; Wang, Haitao; Wu, Kung-Chien

    2018-04-01

    We study the quantitative pointwise behavior of the solutions of the linearized Boltzmann equation for hard potentials, Maxwellian molecules and soft potentials, with Grad's angular cutoff assumption. More precisely, for solutions inside the finite Mach number region (time like region), we obtain the pointwise fluid structure for hard potentials and Maxwellian molecules, and optimal time decay in the fluid part and sub-exponential time decay in the non-fluid part for soft potentials. For solutions outside the finite Mach number region (space like region), we obtain sub-exponential decay in the space variable. The singular wave estimate, regularization estimate and refined weighted energy estimate play important roles in this paper. Our results extend the classical results of Liu and Yu (Commun Pure Appl Math 57:1543-1608, 2004), (Bull Inst Math Acad Sin 1:1-78, 2006), (Bull Inst Math Acad Sin 6:151-243, 2011) and Lee et al. (Commun Math Phys 269:17-37, 2007) to hard and soft potentials by imposing suitable exponential velocity weight on the initial condition.

  5. Quantitative Pointwise Estimate of the Solution of the Linearized Boltzmann Equation

    Science.gov (United States)

    Lin, Yu-Chu; Wang, Haitao; Wu, Kung-Chien

    2018-06-01

    We study the quantitative pointwise behavior of the solutions of the linearized Boltzmann equation for hard potentials, Maxwellian molecules and soft potentials, with Grad's angular cutoff assumption. More precisely, for solutions inside the finite Mach number region (time like region), we obtain the pointwise fluid structure for hard potentials and Maxwellian molecules, and optimal time decay in the fluid part and sub-exponential time decay in the non-fluid part for soft potentials. For solutions outside the finite Mach number region (space like region), we obtain sub-exponential decay in the space variable. The singular wave estimate, regularization estimate and refined weighted energy estimate play important roles in this paper. Our results extend the classical results of Liu and Yu (Commun Pure Appl Math 57:1543-1608, 2004), (Bull Inst Math Acad Sin 1:1-78, 2006), (Bull Inst Math Acad Sin 6:151-243, 2011) and Lee et al. (Commun Math Phys 269:17-37, 2007) to hard and soft potentials by imposing suitable exponential velocity weight on the initial condition.

  6. Birth weight and risk of adiposity among adult Inuit in Greenland.

    Directory of Open Access Journals (Sweden)

    Pernille Falberg Rønn

    Full Text Available OBJECTIVE: The Inuit population in Greenland has undergone rapid socioeconomic and nutritional changes simultaneously with an increasing prevalence of obesity. Therefore, the objective was to examine fetal programming as part of the aetiology of obesity among Inuit in Greenland by investigating the association between birth weight and measures of body composition and fat distribution in adulthood. METHODS: The study was based on cross-sectional data from a total of 1,473 adults aged 18-61 years in two population-based surveys conducted in Greenland between 1999-2001 and 2005-2010. Information on birth weight was collected from birth records. Adiposity was assessed by anthropometry, fat mass index (FMI, fat-free mass index (FFMI, and visceral (VAT and subcutaneous adipose tissue (SAT estimated by ultrasound. The associations to birth weight were analyzed using linear regression models and quadratic splines. Analyses were stratified by sex, and adjusted for age, birthplace, ancestry and family history of obesity. RESULTS: Spline analyses showed linear relations between birth weight and adult adiposity. In multiple regression analyses, birth weight was positively associated with BMI, waist circumference, FMI, FFMI and SAT with generally weaker associations among women compared to men. Birth weight was only associated with VAT after additional adjustment for waist circumference and appeared to be specific and inverse for men only. CONCLUSIONS: Higher birth weight among Inuit was associated with adiposity in adulthood. More studies are needed to explore a potential inverse association between birth size and VAT.

  7. A computer tool for a minimax criterion in binary response and heteroscedastic simple linear regression models.

    Science.gov (United States)

    Casero-Alonso, V; López-Fidalgo, J; Torsney, B

    2017-01-01

    Binary response models are used in many real applications. For these models the Fisher information matrix (FIM) is proportional to the FIM of a weighted simple linear regression model. The same is also true when the weight function has a finite integral. Thus, optimal designs for one binary model are also optimal for the corresponding weighted linear regression model. The main objective of this paper is to provide a tool for the construction of MV-optimal designs, minimizing the maximum of the variances of the estimates, for a general design space. MV-optimality is a potentially difficult criterion because of its nondifferentiability at equal variance designs. A methodology for obtaining MV-optimal designs where the design space is a compact interval [a, b] will be given for several standard weight functions. The methodology will allow us to build a user-friendly computer tool based on Mathematica to compute MV-optimal designs. Some illustrative examples will show a representation of MV-optimal designs in the Euclidean plane, taking a and b as the axes. The applet will be explained using two relevant models. In the first one the case of a weighted linear regression model is considered, where the weight function is directly chosen from a typical family. In the second example a binary response model is assumed, where the probability of the outcome is given by a typical probability distribution. Practitioners can use the provided applet to identify the solution and to know the exact support points and design weights. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  8. Estimating the kinetic parameters of activated sludge storage using weighted non-linear least-squares and accelerating genetic algorithm.

    Science.gov (United States)

    Fang, Fang; Ni, Bing-Jie; Yu, Han-Qing

    2009-06-01

    In this study, weighted non-linear least-squares analysis and accelerating genetic algorithm are integrated to estimate the kinetic parameters of substrate consumption and storage product formation of activated sludge. A storage product formation equation is developed and used to construct the objective function for the determination of its production kinetics. The weighted least-squares analysis is employed to calculate the differences in the storage product concentration between the model predictions and the experimental data as the sum of squared weighted errors. The kinetic parameters for the substrate consumption and the storage product formation are estimated to be the maximum heterotrophic growth rate of 0.121/h, the yield coefficient of 0.44 mg CODX/mg CODS (COD, chemical oxygen demand) and the substrate half saturation constant of 16.9 mg/L, respectively, by minimizing the objective function using a real-coding-based accelerating genetic algorithm. Also, the fraction of substrate electrons diverted to the storage product formation is estimated to be 0.43 mg CODSTO/mg CODS. The validity of our approach is confirmed by the results of independent tests and the kinetic parameter values reported in literature, suggesting that this approach could be useful to evaluate the product formation kinetics of mixed cultures like activated sludge. More importantly, as this integrated approach could estimate the kinetic parameters rapidly and accurately, it could be applied to other biological processes.

  9. Associations of linear growth and relative weight gain during early life with adult health and human capital in countries of low and middle income: findings from five birth cohort studies.

    Science.gov (United States)

    Adair, Linda S; Fall, Caroline H D; Osmond, Clive; Stein, Aryeh D; Martorell, Reynaldo; Ramirez-Zea, Manuel; Sachdev, Harshpal Singh; Dahly, Darren L; Bas, Isabelita; Norris, Shane A; Micklesfield, Lisa; Hallal, Pedro; Victora, Cesar G

    2013-08-10

    Fast weight gain and linear growth in children in low-income and middle-income countries are associated with enhanced survival and improved cognitive development, but might increase risk of obesity and related adult cardiometabolic diseases. We investigated how linear growth and relative weight gain during infancy and childhood are related to health and human capital outcomes in young adults. We used data from five prospective birth cohort studies from Brazil, Guatemala, India, the Philippines, and South Africa. We investigated body-mass index, systolic and diastolic blood pressure, plasma glucose concentration, height, years of attained schooling, and related categorical indicators of adverse outcomes in young adults. With linear and logistic regression models, we assessed how these outcomes relate to birthweight and to statistically independent measures representing linear growth and weight gain independent of linear growth (relative weight gain) in three age periods: 0-2 years, 2 years to mid-childhood, and mid-childhood to adulthood. We obtained data for 8362 participants who had at least one adult outcome of interest. A higher birthweight was consistently associated with an adult body-mass index of greater than 25 kg/m(2) (odds ratio 1·28, 95% CI 1·21-1·35) and a reduced likelihood of short adult stature (0·49, 0·44-0·54) and of not completing secondary school (0·82, 0·78-0·87). Faster linear growth was strongly associated with a reduced risk of short adult stature (age 2 years: 0·23, 0·20-0·52; mid-childhood: 0·39, 0·36-0·43) and of not completing secondary school (age 2 years: 0·74, 0·67-0·78; mid-childhood: 0·87, 0·83-0·92), but did raise the likelihood of overweight (age 2 years: 1·24, 1·17-1·31; mid-childhood: 1·12, 1·06-1·18) and elevated blood pressure (age 2 years: 1·12, 1·06-1·19; mid-childhood: 1·07, 1·01-1·13). Faster relative weight gain was associated with an increased risk of adult overweight (age 2 years: 1·51

  10. Development of planning level transportation safety tools using Geographically Weighted Poisson Regression.

    Science.gov (United States)

    Hadayeghi, Alireza; Shalaby, Amer S; Persaud, Bhagwant N

    2010-03-01

    A common technique used for the calibration of collision prediction models is the Generalized Linear Modeling (GLM) procedure with the assumption of Negative Binomial or Poisson error distribution. In this technique, fixed coefficients that represent the average relationship between the dependent variable and each explanatory variable are estimated. However, the stationary relationship assumed may hide some important spatial factors of the number of collisions at a particular traffic analysis zone. Consequently, the accuracy of such models for explaining the relationship between the dependent variable and the explanatory variables may be suspected since collision frequency is likely influenced by many spatially defined factors such as land use, demographic characteristics, and traffic volume patterns. The primary objective of this study is to investigate the spatial variations in the relationship between the number of zonal collisions and potential transportation planning predictors, using the Geographically Weighted Poisson Regression modeling technique. The secondary objective is to build on knowledge comparing the accuracy of Geographically Weighted Poisson Regression models to that of Generalized Linear Models. The results show that the Geographically Weighted Poisson Regression models are useful for capturing spatially dependent relationships and generally perform better than the conventional Generalized Linear Models. Copyright 2009 Elsevier Ltd. All rights reserved.

  11. The relationship between prevalence and duration of weight loss strategies and weight loss among overweight managed care organization members enrolled in a weight loss trial

    Directory of Open Access Journals (Sweden)

    Jeffery Robert W

    2006-02-01

    Full Text Available Abstract Background Many adults in the United States report engaging in weight loss behaviors. The current study examined weight loss strategies among managed care organization members, to determine the prevalence and impact of weight loss behaviors in this population. We hypothesized that greater engagement in weight loss strategies would be associated with greater weight loss success. Methods Data were taken from Weigh-to-Be (WTB, a two-year weight loss trial (N = 1801, 72% female, mean age = 50.7 years, mean weight = 95.9 kg, mean BMI = 34.2 kg/m2. Every six months, participants completed a questionnaire assessing frequency and duration of weight loss strategies (calorie reduction, fat reduction, increased fruit/vegetable intake, increased exercise, elimination of sweets, consumption of less food. General linear models and structural equation methods were used to examine associations between weight loss strategy use and weight change over time. Results Weight loss strategy prevalence rates ranged from 68% to 76% over two years. For all dietary strategies, any use of the strategy between baseline and 24 months was associated with weight loss at 24 months; those who did not engage in the strategy showed weight gains during that period. Results of general linear models and structural equation models indicated that increased use of weight loss strategies was significantly associated with greater 24-month weight loss. Conclusion The prevalence of weight loss strategies in this obese adult managed care population was quite high, and use of these strategies was associated in dose-response fashion with better weight loss. Future interventions may benefit from emphasis on persistence of similar strategies to achieve more successful outcomes.

  12. Fokker-action principle for a system of particles interacting through a linear potential

    International Nuclear Information System (INIS)

    Rivacoba, A.

    1984-01-01

    A Fokker-action principle for a system of scalar particles interacting through their time-symmetric relativistic generalization of linear potential is obtained. From this action, motion equations and conservation laws for the total energy and angular momentum of the system, in which field contributions are included, are derived. These equations are exactly applied to the problem suggested by Schild of two particles moving in circular concentric orbits

  13. Approximation by modified Szasz–Mirakjan operators on weighted ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    English translation in Math. Notes 20(5–6) (1976) 996–998. [3] Gadzhiev A D, Positive linear operators in weighted spaces of functions of several vari- ables, Izv. Akad. Nauk. SSR Ser. Fiz-Tekhn. Math. Nauk 4 (1980) 32–37. [4] Gadzhiev A D, Weighted approximation of continuous functions by linear operators on the whole ...

  14. Comparison of height-diameter models based on geographically weighted regressions and linear mixed modelling applied to large scale forest inventory data

    Energy Technology Data Exchange (ETDEWEB)

    Quirós Segovia, M.; Condés Ruiz, S.; Drápela, K.

    2016-07-01

    Aim of the study: The main objective of this study was to test Geographically Weighted Regression (GWR) for developing height-diameter curves for forests on a large scale and to compare it with Linear Mixed Models (LMM). Area of study: Monospecific stands of Pinus halepensis Mill. located in the region of Murcia (Southeast Spain). Materials and Methods: The dataset consisted of 230 sample plots (2582 trees) from the Third Spanish National Forest Inventory (SNFI) randomly split into training data (152 plots) and validation data (78 plots). Two different methodologies were used for modelling local (Petterson) and generalized height-diameter relationships (Cañadas I): GWR, with different bandwidths, and linear mixed models. Finally, the quality of the estimated models was compared throughout statistical analysis. Main results: In general, both LMM and GWR provide better prediction capability when applied to a generalized height-diameter function than when applied to a local one, with R2 values increasing from around 0.6 to 0.7 in the model validation. Bias and RMSE were also lower for the generalized function. However, error analysis showed that there were no large differences between these two methodologies, evidencing that GWR provides results which are as good as the more frequently used LMM methodology, at least when no additional measurements are available for calibrating. Research highlights: GWR is a type of spatial analysis for exploring spatially heterogeneous processes. GWR can model spatial variation in tree height-diameter relationship and its regression quality is comparable to LMM. The advantage of GWR over LMM is the possibility to determine the spatial location of every parameter without additional measurements. Abbreviations: GWR (Geographically Weighted Regression); LMM (Linear Mixed Model); SNFI (Spanish National Forest Inventory). (Author)

  15. Magnetism of hexagonal close-packed nickel calculated by full-potential linearized augmented plane wave method

    International Nuclear Information System (INIS)

    Tian, F.; Tian, H.; Whitmore, L.; Ye, L.Y.

    2015-01-01

    The energy dependent on volume of hexagonal close-packed (hcp) nickel with different magnetism is calculated by full-potential linearized augmented plane wave method. Based on the calculation ferromagnetic state is found to be the most stable state. The magnetic moment of hcp Ni is calculated and compared to those calculated by different pseudo-potential methods. Furthermore, it is also compared to that of face-centered cubic (fcc) one with the reason discussed

  16. Weight change in a commercial web-based weight loss program and its association with website use: cohort study.

    Science.gov (United States)

    Neve, Melinda; Morgan, Philip J; Collins, Clare E

    2011-10-12

    There is a paucity of information in the scientific literature on the effectiveness of commercial weight loss programs, including Web-based programs. The potential of Web-based weight loss programs has been acknowledged, but their ability to achieve significant weight loss has not been proven. The objectives were to evaluate the weight change achieved within a large cohort of individuals enrolled in a commercial Web-based weight loss program for 12 or 52 weeks and to describe participants' program use in relation to weight change. Participants enrolled in an Australian commercial Web-based weight loss program from August 15, 2007, through May 31, 2008. Self-reported weekly weight records were used to determine weight change after 12- and 52-week subscriptions. The primary analysis estimated weight change using generalized linear mixed models (GLMMs) for all participants who subscribed for 12 weeks and also for those who subscribed for 52 weeks. A sensitivity analysis was conducted using the last observation carried forward (LOCF) method. Website use (ie, the number of days participants logged on, made food or exercise entries to the Web-based diary, or posted to the discussion forum) was described from program enrollment to 12 and 52 weeks, and differences in website use by percentage weight change category were tested using Kruskal-Wallis test for equality of populations. Participants (n = 9599) had a mean (standard deviation [SD]) age of 35.7 (9.5) years and were predominantly female (86% or 8279/9599) and obese (61% or 5866/9599). Results from the primary GLMM analysis including all enrollees found the mean percentage weight change was -6.2% among 12-week subscribers (n = 6943) and -6.9% among 52-week subscribers (n = 2656). Sensitivity analysis using LOCF revealed an average weight change of -3.0% and -3.5% after 12 and 52 weeks respectively. The use of all website features increased significantly (P Web-based weight loss program is likely to be in the range of

  17. Ultrahigh Molecular Weight Linear Block Copolymers: Rapid Access by Reversible-Deactivation Radical Polymerization and Self- Assembly into Large Domain Nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Mapas, Jose Kenneth D.; Thomay, Tim; Cartwright, Alexander N.; Ilavsky, Jan; Rzayev, Javid

    2016-05-05

    Block copolymer (BCP) derived periodic nanostructures with domain sizes larger than 150 nm present a versatile platform for the fabrication of photonic materials. So far, the access to such materials has been limited to highly synthetically involved protocols. Herein, we report a simple, “user-friendly” method for the preparation of ultrahigh molecular weight linear poly(solketal methacrylate-b-styrene) block copolymers by a combination of Cu-wire-mediated ATRP and RAFT polymerizations. The synthesized copolymers with molecular weights up to 1.6 million g/mol and moderate dispersities readily assemble into highly ordered cylindrical or lamella microstructures with domain sizes as large as 292 nm, as determined by ultra-small-angle x-ray scattering and scanning electron microscopy analyses. Solvent cast films of the synthesized block copolymers exhibit stop bands in the visible spectrum correlated to their domain spacings. The described method opens new avenues for facilitated fabrication and the advancement of fundamental understanding of BCP-derived photonic nanomaterials for a variety of applications.

  18. On quantum motion of particle in linear potential bounded by perfectly reflecting plane and parabolic surfaces

    International Nuclear Information System (INIS)

    Pokotilovskij, Yu.N.

    1999-01-01

    The motion of a particle in the linear potential bounded by an inclined plane or parabolic surfaces is considered. The quantization of energy and wave functions is obtained numerically by the separation of the variables method

  19. Estimating Body Weight of Cattle Using Linear Body Measurements ...

    African Journals Online (AJOL)

    The relationships between body weight (BW) and heart girth, body length and height at withers of 116 Indigenous, 72 Friesian, 95 Brahman, 88 Red Dane and 123 Crossbred cattle from 42 smallholder herds in Nharira-Lancashire, Zimbabwe, were investigated. The principal objective was to develop simple models that ...

  20. Potential pathways by which maternal second-hand smoke exposure during pregnancy causes full-term low birth weight.

    Science.gov (United States)

    Niu, Zhongzheng; Xie, Chuanbo; Wen, Xiaozhong; Tian, Fuying; Yuan, Shixin; Jia, Deqin; Chen, Wei-Qing

    2016-04-29

    It is well documented that maternal exposure to second-hand smoke (SHS) during pregnancy causes low birth weight (LBW), but its mechanism remains unknown. This study explored the potential pathways. We enrolled 195 pregnant women who delivered full-term LBW newborns, and 195 who delivered full-term normal birth weight newborns as the controls. After controlling for maternal age, education level, family income, pre-pregnant body mass index, newborn gender and gestational age, logistic regression analysis revealed that LBW was significantly and positively associated with maternal exposure to SHS during pregnancy, lower placental weight, TNF-α and IL-1β, and that SHS exposure was significantly associated with lower placental weight, TNF-α and IL-1β. Structural equation modelling identified two plausible pathways by which maternal exposure to SHS during pregnancy might cause LBW. First, SHS exposure induced the elevation of TNF-α, which might directly increase the risk of LBW by transmission across the placenta. Second, SHS exposure first increased maternal secretion of IL-1β and TNF-α, which then triggered the secretion of VCAM-1; both TNF-α and VCAM-1 were significantly associated with lower placental weight, thus increasing the risk of LBW. In conclusion, maternal exposure to SHS during pregnancy may lead to LBW through the potential pathways of maternal inflammation and lower placental weight.

  1. Selecting the correct weighting factors for linear and quadratic calibration curves with least-squares regression algorithm in bioanalytical LC-MS/MS assays and impacts of using incorrect weighting factors on curve stability, data quality, and assay performance.

    Science.gov (United States)

    Gu, Huidong; Liu, Guowen; Wang, Jian; Aubry, Anne-Françoise; Arnold, Mark E

    2014-09-16

    A simple procedure for selecting the correct weighting factors for linear and quadratic calibration curves with least-squares regression algorithm in bioanalytical LC-MS/MS assays is reported. The correct weighting factor is determined by the relationship between the standard deviation of instrument responses (σ) and the concentrations (x). The weighting factor of 1, 1/x, or 1/x(2) should be selected if, over the entire concentration range, σ is a constant, σ(2) is proportional to x, or σ is proportional to x, respectively. For the first time, we demonstrated with detailed scientific reasoning, solid historical data, and convincing justification that 1/x(2) should always be used as the weighting factor for all bioanalytical LC-MS/MS assays. The impacts of using incorrect weighting factors on curve stability, data quality, and assay performance were thoroughly investigated. It was found that the most stable curve could be obtained when the correct weighting factor was used, whereas other curves using incorrect weighting factors were unstable. It was also found that there was a very insignificant impact on the concentrations reported with calibration curves using incorrect weighting factors as the concentrations were always reported with the passing curves which actually overlapped with or were very close to the curves using the correct weighting factor. However, the use of incorrect weighting factors did impact the assay performance significantly. Finally, the difference between the weighting factors of 1/x(2) and 1/y(2) was discussed. All of the findings can be generalized and applied into other quantitative analysis techniques using calibration curves with weighted least-squares regression algorithm.

  2. LENGTH-WEIGHT RELATIONSHIP AND CONDITION FACTOR OF ...

    African Journals Online (AJOL)

    Data Collection and Analysis. The measurements of length (cm), weight (g) and the condition factor of individual fish sampled were recorded. The relationship between length and weight of the fish was examined by simple linear regression using WINKS software. The variations in the length-weight represented by 'b' were.

  3. End-weight prediction in broiler growth

    NARCIS (Netherlands)

    Cangar, O.; Aerts, J.-M.; Vranken, E.; Berckmans, D.

    2006-01-01

    1. Two different methods, categorised as input-output and single output models, were evaluated for slaughter weight prediction of broiler chickens. The input-output models included linear and non-linear recursive modelling with a time-varying model structure, whereas the output models consisted only

  4. Nutritional status and weight gain in pregnant women.

    Science.gov (United States)

    Sato, Ana Paula Sayuri; Fujimori, Elizabeth

    2012-01-01

    This study described the nutritional status of 228 pregnant women and the influence of this on birth weight. This is a retrospective study, developed in a health center in the municipality of São Paulo, with data obtained from medical records. Linear regression analysis was carried out. An association was verified between the initial and final nutritional status (ppregnancy underweight was higher compared those who started overweight/obese (p=0.005). Weight gain was insufficient for 43.4% of the pregnant women with adequate initial weight and for 36.4% of all the pregnant women studied. However, 37.1% of those who began the pregnancy overweight/obese finished with excessive weight gain, a condition that ultimately affected almost a quarter of the pregnant women. Anemia and low birth weight were uncommon, however, in the linear regression analysis, birth weight was associated with weight gain (pimportance of nutritional care before and during pregnancy to promote maternal-infant health.

  5. Closed-form solutions for linear regulator design of mechanical systems including optimal weighting matrix selection

    Science.gov (United States)

    Hanks, Brantley R.; Skelton, Robert E.

    1991-01-01

    Vibration in modern structural and mechanical systems can be reduced in amplitude by increasing stiffness, redistributing stiffness and mass, and/or adding damping if design techniques are available to do so. Linear Quadratic Regulator (LQR) theory in modern multivariable control design, attacks the general dissipative elastic system design problem in a global formulation. The optimal design, however, allows electronic connections and phase relations which are not physically practical or possible in passive structural-mechanical devices. The restriction of LQR solutions (to the Algebraic Riccati Equation) to design spaces which can be implemented as passive structural members and/or dampers is addressed. A general closed-form solution to the optimal free-decay control problem is presented which is tailored for structural-mechanical system. The solution includes, as subsets, special cases such as the Rayleigh Dissipation Function and total energy. Weighting matrix selection is a constrained choice among several parameters to obtain desired physical relationships. The closed-form solution is also applicable to active control design for systems where perfect, collocated actuator-sensor pairs exist.

  6. Cord Blood Metabolome Is Highly Associated with Birth Weight, but Less Predictive for Later Weight Development

    Directory of Open Access Journals (Sweden)

    Christian Hellmuth

    2017-04-01

    Full Text Available Background/Aims: Fetal metabolism may be changed by the exposure to maternal factors, and the route to obesity may already set in utero. Cord blood metabolites might predict growth patterns and later obesity. We aimed to characterize associations of cord blood with birth weight, postnatal weight gain, and BMI in adolescence. Methods: Over 700 cord blood samples were collected from infants participating in the German birth cohort study LISAplus. Glycerophospholipid fatty acids (GPL-FA, polar lipids, non-esterified fatty acids (NEFA, and amino acids were analyzed with a targeted, liquid chromatography-tandem mass spectrometry based metabolomics platform. Cord blood metabolites were related to growth factors by linear regression models adjusted for confounding variables. Results: Cord blood metabolites were highly associated with birth weight. Lysophosphatidylcholines C16:1, C18:1, C20:3, C18:2, C20:4, C14:0, C16:0, C18:3, GPL-FA C20:3n-9, and GPL-FA C22:5n-6 were positively related to birth weight, while higher cord blood concentrations of NEFA C22:6, NEFA C20:5, GPL-FA C18:3n-3, and PCe C38:0 were associated with lower birth weight. Postnatal weight gain and BMI z-scores in adolescents were not significantly associated with cord blood metabolites after adjustment for multiple testing. Conclusion: Potential long-term programming effects of the intrauterine environment and metabolism on later health cannot be predicted with profiling of the cord blood metabolome.

  7. High Signal Intensity in the Dentate Nucleus and Globus Pallidus on Unenhanced T1-Weighted MR Images: Comparison between Gadobutrol and Linear Gadolinium-Based Contrast Agents.

    Science.gov (United States)

    Moser, F G; Watterson, C T; Weiss, S; Austin, M; Mirocha, J; Prasad, R; Wang, J

    2018-02-01

    In view of the recent observations that gadolinium deposits in brain tissue after intravenous injection, our aim of this study was to compare signal changes in the globus pallidus and dentate nucleus on unenhanced T1-weighted MR images in patients receiving serial doses of gadobutrol, a macrocyclic gadolinium-based contrast agent, with those seen in patients receiving linear gadolinium-based contrast agents. This was a retrospective analysis of on-site patients with brain tumors. Fifty-nine patients received only gadobutrol, and 60 patients received only linear gadolinium-based contrast agents. Linear gadolinium-based contrast agents included gadoversetamide, gadobenate dimeglumine, and gadodiamide. T1 signal intensity in the globus pallidus, dentate nucleus, and pons was measured on the precontrast portions of patients' first and seventh brain MRIs. Ratios of signal intensity comparing the globus pallidus with the pons (globus pallidus/pons) and dentate nucleus with the pons (dentate nucleus/pons) were calculated. Changes in the above signal intensity ratios were compared within the gadobutrol and linear agent groups, as well as between groups. The dentate nucleus/pons signal ratio increased in the linear gadolinium-based contrast agent group ( t = 4.215, P linear gadolinium-based contrast agent group ( t = 2.931, P linear gadolinium-based contrast agents. © 2018 by American Journal of Neuroradiology.

  8. Birth weight recovery among very low birth weight infants surviving ...

    African Journals Online (AJOL)

    A multiple linear regression showed a negative association between ZSW at discharge and number of days nil per os without parenteral nutrition (PN). Antenatal steroids were associated with poor GV. There were no factors associated with regaining birth weight after 21 days on multiple logistic regression. Conclusion.

  9. Regression Equations for Birth Weight Estimation using ...

    African Journals Online (AJOL)

    In this study, Birth Weight has been estimated from anthropometric measurements of hand and foot. Linear regression equations were formed from each of the measured variables. These simple equations can be used to estimate Birth Weight of new born babies, in order to identify those with low birth weight and referred to ...

  10. Applying Monte Carlo Concept and Linear Programming in Modern Portfolio Theory to Obtain Best Weighting Structure

    Directory of Open Access Journals (Sweden)

    Tumpal Sihombing

    2013-01-01

    Full Text Available The world is entering the era of recession when the trend is bearish and market is not so favorable. The capital markets in every major country were experiencing great amount of loss and people suffered in their investment. The Jakarta Composite Index (JCI has shown a great downturn for the past one year but the trend bearish year of the JCI. Therefore, rational investors should consider restructuring their portfolio to set bigger proportion in bonds and cash instead of stocks. Investors can apply modern portfolio theory by Harry Markowitz to find the optimum asset allocation for their portfolio. Higher return is always associated with higher risk. This study shows investors how to find out the lowest risk of a portfolio investment by providing them with several structures of portfolio weighting. By this way, investor can compare and make the decision based on risk-return consideration and opportunity cost as well. Keywords: Modern portfolio theory, Monte Carlo, linear programming

  11. Multiplex protein pattern unmixing using a non-linear variable-weighted support vector machine as optimized by a particle swarm optimization algorithm.

    Science.gov (United States)

    Yang, Qin; Zou, Hong-Yan; Zhang, Yan; Tang, Li-Juan; Shen, Guo-Li; Jiang, Jian-Hui; Yu, Ru-Qin

    2016-01-15

    Most of the proteins locate more than one organelle in a cell. Unmixing the localization patterns of proteins is critical for understanding the protein functions and other vital cellular processes. Herein, non-linear machine learning technique is proposed for the first time upon protein pattern unmixing. Variable-weighted support vector machine (VW-SVM) is a demonstrated robust modeling technique with flexible and rational variable selection. As optimized by a global stochastic optimization technique, particle swarm optimization (PSO) algorithm, it makes VW-SVM to be an adaptive parameter-free method for automated unmixing of protein subcellular patterns. Results obtained by pattern unmixing of a set of fluorescence microscope images of cells indicate VW-SVM as optimized by PSO is able to extract useful pattern features by optimally rescaling each variable for non-linear SVM modeling, consequently leading to improved performances in multiplex protein pattern unmixing compared with conventional SVM and other exiting pattern unmixing methods. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Weighted approximation with varying weight

    CERN Document Server

    Totik, Vilmos

    1994-01-01

    A new construction is given for approximating a logarithmic potential by a discrete one. This yields a new approach to approximation with weighted polynomials of the form w"n"(" "= uppercase)P"n"(" "= uppercase). The new technique settles several open problems, and it leads to a simple proof for the strong asymptotics on some L p(uppercase) extremal problems on the real line with exponential weights, which, for the case p=2, are equivalent to power- type asymptotics for the leading coefficients of the corresponding orthogonal polynomials. The method is also modified toyield (in a sense) uniformly good approximation on the whole support. This allows one to deduce strong asymptotics in some L p(uppercase) extremal problems with varying weights. Applications are given, relating to fast decreasing polynomials, asymptotic behavior of orthogonal polynomials and multipoint Pade approximation. The approach is potential-theoretic, but the text is self-contained.

  13. On Weighted Support Vector Regression

    DEFF Research Database (Denmark)

    Han, Xixuan; Clemmensen, Line Katrine Harder

    2014-01-01

    We propose a new type of weighted support vector regression (SVR), motivated by modeling local dependencies in time and space in prediction of house prices. The classic weights of the weighted SVR are added to the slack variables in the objective function (OF‐weights). This procedure directly...... shrinks the coefficient of each observation in the estimated functions; thus, it is widely used for minimizing influence of outliers. We propose to additionally add weights to the slack variables in the constraints (CF‐weights) and call the combination of weights the doubly weighted SVR. We illustrate...... the differences and similarities of the two types of weights by demonstrating the connection between the Least Absolute Shrinkage and Selection Operator (LASSO) and the SVR. We show that an SVR problem can be transformed to a LASSO problem plus a linear constraint and a box constraint. We demonstrate...

  14. Preconditioned Iterative Methods for Solving Weighted Linear Least Squares Problems

    Czech Academy of Sciences Publication Activity Database

    Bru, R.; Marín, J.; Mas, J.; Tůma, Miroslav

    2014-01-01

    Roč. 36, č. 4 (2014), A2002-A2022 ISSN 1064-8275 Institutional support: RVO:67985807 Keywords : preconditioned iterative methods * incomplete decompositions * approximate inverses * linear least squares Subject RIV: BA - General Mathematics Impact factor: 1.854, year: 2014

  15. Low Molecular Weight pDMAEMA-block-pHEMA Block-Copolymers Synthesized via RAFT-Polymerization: Potential Non-Viral Gene Delivery Agents?

    Directory of Open Access Journals (Sweden)

    Thomas Kissel

    2011-03-01

    Full Text Available The aim of this study was to investigate non-viral pDNA carriers based on diblock-copolymers consisting of poly(2-(dimethyl aminoethyl methacrylate (pDMAEMA and poly(2-hydroxyethyl methacrylate (pHEMA. Specifically the block-lengths and molecular weights were varied to determine the minimal requirements for transfection. Such vectors should allow better transfection at acceptable toxicity levels and the entire diblock-copolymer should be suitable for renal clearance. For this purpose, a library of linear poly(2-(dimethyl aminoethyl methacrylate-block-poly(2-hydroxyl methacrylate (pDMAEMA-block-pHEMA copolymers was synthesized via RAFT (reversible addition-fragmentation chain transfer polymerization in a molecular weight (Mw range of 17–35.7 kDa and analyzed using 1H and 13C NMR (nuclear magnetic resonance, ATR (attenuated total reflectance, GPC (gel permeation chromatography and DSC (differential scanning calorimetry. Copolymers possessing short pDMAEMA-polycation chains were 1.4–9.7 times less toxic in vitro than polyethylenimine (PEI 25 kDa, and complexed DNA into polyplexes of 100–170 nm, favorable for cellular uptake. The DNA-binding affinity and polyplex stability against competing polyanions was comparable with PEI 25 kDa. The zeta-potential of polyplexes of pDMAEMA-grafted copolymers remained positive (+15–30 mV. In comparison with earlier reported low molecular weight homo pDMAEMA vectors, these diblock-copolymers showed enhanced transfection efficacy under in vitro conditions due to their lower cytotoxicity, efficient cellular uptake and DNA packaging. The homo pDMAEMA115 (18.3 kDa self-assembled with DNA into small positively charged polyplexes, but was not able to transfect cells. The grafting of 6 and 57 repeating units of pHEMA (0.8 and 7.4 kDa to pDMAEMA115 increased the transfection efficacy significantly, implying a crucial impact of pHEMA on vector-cell interactions. The intracellular trafficking, in vivo transfection

  16. Non-linear multivariable predictive control of an alcoholic fermentation process using functional link networks

    Directory of Open Access Journals (Sweden)

    Luiz Augusto da Cruz Meleiro

    2005-06-01

    Full Text Available In this work a MIMO non-linear predictive controller was developed for an extractive alcoholic fermentation process. The internal model of the controller was represented by two MISO Functional Link Networks (FLNs, identified using simulated data generated from a deterministic mathematical model whose kinetic parameters were determined experimentally. The FLN structure presents as advantages fast training and guaranteed convergence, since the estimation of the weights is a linear optimization problem. Besides, the elimination of non-significant weights generates parsimonious models, which allows for fast execution in an MPC-based algorithm. The proposed algorithm showed good potential in identification and control of non-linear processes.Neste trabalho um controlador preditivo não linear multivariável foi desenvolvido para um processo de fermentação alcoólica extrativa. O modelo interno do controlador foi representado por duas redes do tipo Functional Link (FLN, identificadas usando dados de simulação gerados a partir de um modelo validado experimentalmente. A estrutura FLN apresenta como vantagem o treinamento rápido e convergência garantida, já que a estimação dos seus pesos é um problema de otimização linear. Além disso, a eliminação de pesos não significativos gera modelos parsimoniosos, o que permite a rápida execução em algoritmos de controle preditivo baseado em modelo. Os resultados mostram que o algoritmo proposto tem grande potencial para identificação e controle de processos não lineares.

  17. Some observations on weighted GMRES

    KAUST Repository

    Güttel, Stefan

    2014-01-10

    We investigate the convergence of the weighted GMRES method for solving linear systems. Two different weighting variants are compared with unweighted GMRES for three model problems, giving a phenomenological explanation of cases where weighting improves convergence, and a case where weighting has no effect on the convergence. We also present a new alternative implementation of the weighted Arnoldi algorithm which under known circumstances will be favourable in terms of computational complexity. These implementations of weighted GMRES are compared for a large number of examples. We find that weighted GMRES may outperform unweighted GMRES for some problems, but more often this method is not competitive with other Krylov subspace methods like GMRES with deflated restarting or BICGSTAB, in particular when a preconditioner is used. © 2014 Springer Science+Business Media New York.

  18. Some observations on weighted GMRES

    KAUST Repository

    Gü ttel, Stefan; Pestana, Jennifer

    2014-01-01

    We investigate the convergence of the weighted GMRES method for solving linear systems. Two different weighting variants are compared with unweighted GMRES for three model problems, giving a phenomenological explanation of cases where weighting improves convergence, and a case where weighting has no effect on the convergence. We also present a new alternative implementation of the weighted Arnoldi algorithm which under known circumstances will be favourable in terms of computational complexity. These implementations of weighted GMRES are compared for a large number of examples. We find that weighted GMRES may outperform unweighted GMRES for some problems, but more often this method is not competitive with other Krylov subspace methods like GMRES with deflated restarting or BICGSTAB, in particular when a preconditioner is used. © 2014 Springer Science+Business Media New York.

  19. Mixed linear-nonlinear fault slip inversion: Bayesian inference of model, weighting, and smoothing parameters

    Science.gov (United States)

    Fukuda, J.; Johnson, K. M.

    2009-12-01

    Studies utilizing inversions of geodetic data for the spatial distribution of coseismic slip on faults typically present the result as a single fault plane and slip distribution. Commonly the geometry of the fault plane is assumed to be known a priori and the data are inverted for slip. However, sometimes there is not strong a priori information on the geometry of the fault that produced the earthquake and the data is not always strong enough to completely resolve the fault geometry. We develop a method to solve for the full posterior probability distribution of fault slip and fault geometry parameters in a Bayesian framework using Monte Carlo methods. The slip inversion problem is particularly challenging because it often involves multiple data sets with unknown relative weights (e.g. InSAR, GPS), model parameters that are related linearly (slip) and nonlinearly (fault geometry) through the theoretical model to surface observations, prior information on model parameters, and a regularization prior to stabilize the inversion. We present the theoretical framework and solution method for a Bayesian inversion that can handle all of these aspects of the problem. The method handles the mixed linear/nonlinear nature of the problem through combination of both analytical least-squares solutions and Monte Carlo methods. We first illustrate and validate the inversion scheme using synthetic data sets. We then apply the method to inversion of geodetic data from the 2003 M6.6 San Simeon, California earthquake. We show that the uncertainty in strike and dip of the fault plane is over 20 degrees. We characterize the uncertainty in the slip estimate with a volume around the mean fault solution in which the slip most likely occurred. Slip likely occurred somewhere in a volume that extends 5-10 km in either direction normal to the fault plane. We implement slip inversions with both traditional, kinematic smoothing constraints on slip and a simple physical condition of uniform stress

  20. Weight-Control Methods, 3-Year Weight Change, and Eating Behaviors: A Prospective Nationwide Study of Middle-Aged New Zealand Women.

    Science.gov (United States)

    Leong, Sook Ling; Gray, Andrew; Haszard, Jillian; Horwath, Caroline

    2016-08-01

    The effectiveness of women's weight-control methods and the influences of dieting on eating behaviors remain unclear. Our aim was to determine the association of various weight-control methods at baseline with weight change to 3 years, and examine the association between baseline weight-control status (trying to lose weight, trying to prevent weight gain or no weight-control attempts) and changes in intuitive eating and binge eating at 3 years. A nationally representative sample of 1,601 New Zealand women (40 to 50 years) was recruited and completed a self-administered questionnaire at baseline regarding use of variety of weight-control methods. Information on demographic characteristics, weight, height, food habits, binge eating, and intuitive eating were collected at baseline and 3 years. Linear and logistic regression models examined associations between both weight status and weight-control methods at baseline and weight change to 3 years; and baseline weight-control status and change in intuitive eating from baseline to 3 years and binge eating at 3 years. χ(2) tests were used to cross-sectionally compare food habits across the weight status categories at both baseline and 3 years. Trying to lose weight and the use of weight-control methods at baseline were not associated with change in body weight to 3 years. There were a few differences in the frequency of consumption of high-energy-density foods between those trying to lose or maintain weight and those not attempting weight control. Trying to lose weight at baseline was associated with a 2.0-unit (95% CI 0.7 to 3.4, P=0.003) reduction in intuitive eating scores by 3 years (potential range=21 to 105), and 224% (odds ratio=3.24; 95% CI 1.69 to 6.20; Pfoods. Dieting may reduce women's ability to recognize hunger and satiety cues and place women at increased risk of binge eating. Copyright © 2016 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

  1. Sports and leisure-time physical activity in pregnancy and birth weight

    DEFF Research Database (Denmark)

    Hegaard, Hanne Kristine; Petersson, K; Hedegaard, M

    2010-01-01

    We examined the association between sports and other leisure-time physical activities during pregnancy and birth weight of babies born after 37 completed weeks of gestation. All Danish-speaking pregnant women attending routine antenatal care at the Department of Obstetrics, Aarhus University......, light, and moderate to heavy) and birth weight were examined by linear and logistic regression and adjusted for potential confounding factors such as smoking, parity, schooling, pre-pregnancy body mass index and gestational age. The results showed that pregnant women who practiced sports or were...... moderate to heavy leisure-time physical active during the early second or the early third trimester gave birth to infants with a similar birth weight as inactive women. The proportion of newborns with a low (/=4500 g) was also unchanged. In conclusion, in this large population-based study, we found...

  2. Linearized Programming of Memristors for Artificial Neuro-Sensor Signal Processing.

    Science.gov (United States)

    Yang, Changju; Kim, Hyongsuk

    2016-08-19

    A linearized programming method of memristor-based neural weights is proposed. Memristor is known as an ideal element to implement a neural synapse due to its embedded functions of analog memory and analog multiplication. Its resistance variation with a voltage input is generally a nonlinear function of time. Linearization of memristance variation about time is very important for the easiness of memristor programming. In this paper, a method utilizing an anti-serial architecture for linear programming is proposed. The anti-serial architecture is composed of two memristors with opposite polarities. It linearizes the variation of memristance due to complimentary actions of two memristors. For programming a memristor, additional memristor with opposite polarity is employed. The linearization effect of weight programming of an anti-serial architecture is investigated and memristor bridge synapse which is built with two sets of anti-serial memristor architecture is taken as an application example of the proposed method. Simulations are performed with memristors of both linear drift model and nonlinear model.

  3. A converse to linear independence criteria, valid almost everywhere

    DEFF Research Database (Denmark)

    Fischler, Stéphane; Hussain, Mumtaz; Kristensen, Simon

    We prove a weighted analogue of the Khintchine-Groshev Theorem, where the distance to the nearest integer is replaced by the absolute value. This is subsequently applied to proving the optimality of several linear independence criteria over the field of rational numbers.......We prove a weighted analogue of the Khintchine-Groshev Theorem, where the distance to the nearest integer is replaced by the absolute value. This is subsequently applied to proving the optimality of several linear independence criteria over the field of rational numbers....

  4. Linear algebraic methods applied to intensity modulated radiation therapy.

    Science.gov (United States)

    Crooks, S M; Xing, L

    2001-10-01

    Methods of linear algebra are applied to the choice of beam weights for intensity modulated radiation therapy (IMRT). It is shown that the physical interpretation of the beam weights, target homogeneity and ratios of deposited energy can be given in terms of matrix equations and quadratic forms. The methodology of fitting using linear algebra as applied to IMRT is examined. Results are compared with IMRT plans that had been prepared using a commercially available IMRT treatment planning system and previously delivered to cancer patients.

  5. Proprioceptive evoked potentials in man: cerebral responses to changing weight loads on the hand

    DEFF Research Database (Denmark)

    Arnfred, S; He, Chen; Eder, D

    2000-01-01

    We studied cerebral evoked potentials on the scalp to the stimulation of the right hand from a change in weight of 400-480 g in ten subjects. Rise-time was 20g/10 ms, Inter Stimulus Interval 2s and stimulus duration was 100 ms. The cerebral activations were a double positive contralateral C3'/P70...

  6. Association between Weight and Smoking Not Mediated by Weight Loss Attempts or Bullying.

    Science.gov (United States)

    Minaker, Leia M; Leatherdale, Scott T

    2016-01-01

    Youth smoking and obesity may both be mediated by weight control behaviors and experiences of bullying. This study examines associations between smoking and obesity among youth, and explores whether associations are mediated by weight loss attempts or bullying experiences. Data from 24,173 grade 9 to 12 students in the COMPASS study (2012-13) were used to examine the prevalence of self-reported smoking, weight status, attempting to lose weight, and being a victim of bullying. Generalized linear mixed effects models were used to examine correlates of smoking. Among youth, 11% reported currently smoking, 20% were overweight or obese, 42% reported attempting to lose weight, and 18% reported being bullied. Girls who reported attempting to lose weight had higher odds of smoking (OR = 1.42, p = .0039), and students who reported being bullied had higher odds of smoking (OR = 1.85, p weight status. For girls, weight loss attempts were associated with smoking. For both sexes, being bullied was associated with smoking, independent of weight status. Programs attempting to reduce smoking among youth should consider the effects of weight control behaviors and bullying irrespective of weight status.

  7. Monte Carlo simulation of star/linear and star/star blends with chemically identical monomers

    Energy Technology Data Exchange (ETDEWEB)

    Theodorakis, P E [Department of Materials Science and Engineering, University of Ioannina, 45110 Ioannina (Greece); Avgeropoulos, A [Department of Materials Science and Engineering, University of Ioannina, 45110 Ioannina (Greece); Freire, J J [Departamento de Ciencias y Tecnicas FisicoquImicas, Universidad Nacional de Educacion a Distancia, Facultad de Ciencias, Senda del Rey 9, 28040 Madrid (Spain); Kosmas, M [Department of Chemistry, University of Ioannina, 45110 Ioannina (Greece); Vlahos, C [Department of Chemistry, University of Ioannina, 45110 Ioannina (Greece)

    2007-11-21

    The effects of chain size and architectural asymmetry on the miscibility of blends with chemically identical monomers, differing only in their molecular weight and architecture, are studied via Monte Carlo simulation by using the bond fluctuation model. Namely, we consider blends composed of linear/linear, star/linear and star/star chains. We found that linear/linear blends are more miscible than the corresponding star/star mixtures. In star/linear blends, the increase in the volume fraction of the star chains increases the miscibility. For both star/linear and star/star blends, the miscibility decreases with the increase in star functionality. When we increase the molecular weight of linear chains of star/linear mixtures the miscibility decreases. Our findings are compared with recent analytical and experimental results.

  8. Monte Carlo simulation of star/linear and star/star blends with chemically identical monomers

    Science.gov (United States)

    Theodorakis, P. E.; Avgeropoulos, A.; Freire, J. J.; Kosmas, M.; Vlahos, C.

    2007-11-01

    The effects of chain size and architectural asymmetry on the miscibility of blends with chemically identical monomers, differing only in their molecular weight and architecture, are studied via Monte Carlo simulation by using the bond fluctuation model. Namely, we consider blends composed of linear/linear, star/linear and star/star chains. We found that linear/linear blends are more miscible than the corresponding star/star mixtures. In star/linear blends, the increase in the volume fraction of the star chains increases the miscibility. For both star/linear and star/star blends, the miscibility decreases with the increase in star functionality. When we increase the molecular weight of linear chains of star/linear mixtures the miscibility decreases. Our findings are compared with recent analytical and experimental results.

  9. Monte Carlo simulation of star/linear and star/star blends with chemically identical monomers

    International Nuclear Information System (INIS)

    Theodorakis, P E; Avgeropoulos, A; Freire, J J; Kosmas, M; Vlahos, C

    2007-01-01

    The effects of chain size and architectural asymmetry on the miscibility of blends with chemically identical monomers, differing only in their molecular weight and architecture, are studied via Monte Carlo simulation by using the bond fluctuation model. Namely, we consider blends composed of linear/linear, star/linear and star/star chains. We found that linear/linear blends are more miscible than the corresponding star/star mixtures. In star/linear blends, the increase in the volume fraction of the star chains increases the miscibility. For both star/linear and star/star blends, the miscibility decreases with the increase in star functionality. When we increase the molecular weight of linear chains of star/linear mixtures the miscibility decreases. Our findings are compared with recent analytical and experimental results

  10. Linear Colliders

    International Nuclear Information System (INIS)

    Alcaraz, J.

    2001-01-01

    After several years of study e''+ e''- linear colliders in the TeV range have emerged as the major and optimal high-energy physics projects for the post-LHC era. These notes summarize the present status form the main accelerator and detector features to their physics potential. The LHC era. These notes summarize the present status, from the main accelerator and detector features to their physics potential. The LHC is expected to provide first discoveries in the new energy domain, whereas an e''+ e''- linear collider in the 500 GeV-1 TeV will be able to complement it to an unprecedented level of precision in any possible areas: Higgs, signals beyond the SM and electroweak measurements. It is evident that the Linear Collider program will constitute a major step in the understanding of the nature of the new physics beyond the Standard Model. (Author) 22 refs

  11. Development of non-linear TWB parts

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J.; Yoon, C.S.; Lim, J.D. [Hyundai Motor Company and Kia Motors Corp. (Korea). Advanced Technology Center; Park, H.C. [Hyundai Hysco (Korea). Technical Research Lab.

    2005-07-01

    New manufacturing methods have applied for automotive parts to reduce total weight of car, resulting in improvement of fuel efficiency. TWB technique is applied to auto body parts, especially door inner, side inner and outer panel, and center floor panel to accomplish this goal. We applied non-linear (circular welded) TWB to shock absorber housing (to reduce total weight of shock absorber housing assembly). Welding line and shape of blank were determined by FEM analysis. High formability steel sheet and 440MPa grade high strength steel sheet were laser welded and press formed to final shock absorber housing (S/ABS HSG) panel and assembled with other sub parts. As a result, more than 10% of total weight of shock absorber housing assembly could be reduced compared with the mass of same part manufactured by conventional method. Also circular welding technique made it possible to design optimum welding line of TWB part. This paper is about result of FEM analysis and development procedure of non-linear TWB part (shock absorber housing assembly). (orig.)

  12. Weighted Sum-Rate Maximization Using Weighted MMSE for MIMO-BC Beamforming Design

    DEFF Research Database (Denmark)

    Christensen, Søren; De Carvalho, Elisabeth; Agarwal, Rajiv

    2009-01-01

    This paper studies linear transmit filter design for weighted sum-rate (WSR) maximization in the multiple input multiple output broadcast channel (MIMO-BC). The problem of finding the optimal transmit filter is non-convex and intractable to solve using low complexity methods. Motivated by recent ...

  13. Estimating Loess Plateau Average Annual Precipitation with Multiple Linear Regression Kriging and Geographically Weighted Regression Kriging

    Directory of Open Access Journals (Sweden)

    Qiutong Jin

    2016-06-01

    Full Text Available Estimating the spatial distribution of precipitation is an important and challenging task in hydrology, climatology, ecology, and environmental science. In order to generate a highly accurate distribution map of average annual precipitation for the Loess Plateau in China, multiple linear regression Kriging (MLRK and geographically weighted regression Kriging (GWRK methods were employed using precipitation data from the period 1980–2010 from 435 meteorological stations. The predictors in regression Kriging were selected by stepwise regression analysis from many auxiliary environmental factors, such as elevation (DEM, normalized difference vegetation index (NDVI, solar radiation, slope, and aspect. All predictor distribution maps had a 500 m spatial resolution. Validation precipitation data from 130 hydrometeorological stations were used to assess the prediction accuracies of the MLRK and GWRK approaches. Results showed that both prediction maps with a 500 m spatial resolution interpolated by MLRK and GWRK had a high accuracy and captured detailed spatial distribution data; however, MLRK produced a lower prediction error and a higher variance explanation than GWRK, although the differences were small, in contrast to conclusions from similar studies.

  14. Stochastic Linear Quadratic Optimal Control Problems

    International Nuclear Information System (INIS)

    Chen, S.; Yong, J.

    2001-01-01

    This paper is concerned with the stochastic linear quadratic optimal control problem (LQ problem, for short) for which the coefficients are allowed to be random and the cost functional is allowed to have a negative weight on the square of the control variable. Some intrinsic relations among the LQ problem, the stochastic maximum principle, and the (linear) forward-backward stochastic differential equations are established. Some results involving Riccati equation are discussed as well

  15. Novel nonlinear knowledge-based mean force potentials based on machine learning.

    Science.gov (United States)

    Dong, Qiwen; Zhou, Shuigeng

    2011-01-01

    The prediction of 3D structures of proteins from amino acid sequences is one of the most challenging problems in molecular biology. An essential task for solving this problem with coarse-grained models is to deduce effective interaction potentials. The development and evaluation of new energy functions is critical to accurately modeling the properties of biological macromolecules. Knowledge-based mean force potentials are derived from statistical analysis of proteins of known structures. Current knowledge-based potentials are almost in the form of weighted linear sum of interaction pairs. In this study, a class of novel nonlinear knowledge-based mean force potentials is presented. The potential parameters are obtained by nonlinear classifiers, instead of relative frequencies of interaction pairs against a reference state or linear classifiers. The support vector machine is used to derive the potential parameters on data sets that contain both native structures and decoy structures. Five knowledge-based mean force Boltzmann-based or linear potentials are introduced and their corresponding nonlinear potentials are implemented. They are the DIH potential (single-body residue-level Boltzmann-based potential), the DFIRE-SCM potential (two-body residue-level Boltzmann-based potential), the FS potential (two-body atom-level Boltzmann-based potential), the HR potential (two-body residue-level linear potential), and the T32S3 potential (two-body atom-level linear potential). Experiments are performed on well-established decoy sets, including the LKF data set, the CASP7 data set, and the Decoys “R”Us data set. The evaluation metrics include the energy Z score and the ability of each potential to discriminate native structures from a set of decoy structures. Experimental results show that all nonlinear potentials significantly outperform the corresponding Boltzmann-based or linear potentials, and the proposed discriminative framework is effective in developing knowledge

  16. Suppression of chaos by weak resonant excitations in a non-linear oscillator with a non-symmetric potential

    International Nuclear Information System (INIS)

    Litak, Grzegorz; Syta, Arkadiusz; Borowiec, Marek

    2007-01-01

    We examine the Melnikov criterion for transition to chaos in case of one degree of freedom non-linear oscillator with non-symmetric potential. This system, when subjected to an external periodic force, shows homoclinic transition from regular vibrations to chaos just before escape from a potential well. We focus especially on the effect of a second resonant excitation with a different phase on the system transition to chaos. We propose a way of its control

  17. Fungible weights in logistic regression.

    Science.gov (United States)

    Jones, Jeff A; Waller, Niels G

    2016-06-01

    In this article we develop methods for assessing parameter sensitivity in logistic regression models. To set the stage for this work, we first review Waller's (2008) equations for computing fungible weights in linear regression. Next, we describe 2 methods for computing fungible weights in logistic regression. To demonstrate the utility of these methods, we compute fungible logistic regression weights using data from the Centers for Disease Control and Prevention's (2010) Youth Risk Behavior Surveillance Survey, and we illustrate how these alternate weights can be used to evaluate parameter sensitivity. To make our work accessible to the research community, we provide R code (R Core Team, 2015) that will generate both kinds of fungible logistic regression weights. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  18. Determination of the linear coefficient of thermal expansion in polymer films at the nanoscale: influence of the composition of EVA copolymers and the molecular weight of PMMA.

    Science.gov (United States)

    González-Benito, J; Castillo, E; Cruz-Caldito, J F

    2015-07-28

    Nanothermal-expansion of poly(ethylene-co-vinylacetate), EVA, and poly(methyl methacrylate), PMMA, in the form of films was measured to finally obtain linear coefficients of thermal expansion, CTEs. The simple deflection of a cantilever in an atomic force microscope, AFM, was used to monitor thermal expansions at the nanoscale. The influences of: (a) the structure of EVA in terms of its composition (vinylacetate content) and (b) the size of PMMA chains in terms of the molecular weight were studied. To carry out this, several polymer samples were used, EVA copolymers with different weight percents of the vinylacetate comonomer (12, 18, 25 and 40%) and PMMA polymers with different weight average molecular weights (33.9, 64.8, 75.600 and 360.0 kg mol(-1)). The dependencies of the vinyl acetate weight fraction of EVA and the molecular weight of PMMA on their corresponding CTEs were analyzed to finally explain them using new, intuitive and very simple models based on the rule of mixtures. In the case of EVA copolymers a simple equation considering the weighted contributions of each comonomer was enough to estimate the final CTE above the glass transition temperature. On the other hand, when the molecular weight dependence is considered the free volume concept was used as novelty. The expansion of PMMA, at least at the nanoscale, was well and easily described by the sum of the weighted contributions of the occupied and free volumes, respectively.

  19. Weight misperception and disordered weight control behaviors among U.S. high school students with overweight and obesity: Associations and trends, 1999-2013.

    Science.gov (United States)

    Hazzard, Vivienne M; Hahn, Samantha L; Sonneville, Kendrin R

    2017-08-01

    To examine prevalence of weight misperception (incongruence between one's perceived weight status and one's actual weight status) and disordered weight control behaviors (DWCBs; unhealthy behaviors aiming to control or modify weight), associations between weight misperception and DWCBs, and temporal trends in prevalence and associations among adolescents with overweight and obesity from 1999 to 2013. Self-reported data from eight biennial cycles (1999-2013) of the cross-sectional national Youth Risk Behavior Survey were used in analyses restricted to respondents with overweight/obesity. Data on weight status perception, use of fasting, purging, and diet pills to control weight, sex, race/ethnicity, and grade in school were used in multivariate logistic regression models. Among U.S. high school students with overweight and obesity, no linear temporal trends were detected for prevalence of weight misperception, fasting, or purging between 1999 and 2013, while a significant linear decrease was observed for prevalence of diet pill use between 1999 and 2013 (b=-0.81, pfasting to control weight among males. No significant changes over time in associations of weight misperception with fasting or purging were observed, though the association between weight misperception and diet pill use weakened somewhat across 1999-2013. In the context of increasing prevalence of overweight and obesity, weight misperception appears to be a robust protective factor for DWCBs. Copyright © 2017. Published by Elsevier Ltd.

  20. Pulse Splitting for Harmonic Beamforming in Time-Modulated Linear Arrays

    Directory of Open Access Journals (Sweden)

    Lorenzo Poli

    2014-01-01

    Full Text Available A novel strategy for harmonic beamforming in time-modulated linear arrays is proposed. The pulse splitting technique is exploited to simultaneously generate two harmonic patterns, one at the central frequency and another at a preselected harmonic of arbitrary order, while controlling the maximum level of the remaining sideband radiations. An optimization strategy based on the particle swarm optimizer is developed in order to determine the optimal parameters describing the pulse sequence used to modulate the excitation weights of the array elements. Representative numerical results are reported and discussed to point out potentialities and limitations of the proposed approach.

  1. Genetic parameters for quail body weights using a random ...

    African Journals Online (AJOL)

    A model including fixed and random linear regressions is described for analyzing body weights at different ages. In this study, (co)variance components, heritabilities for quail weekly weights and genetic correlations among these weights were estimated using a random regression model by DFREML under DXMRR option.

  2. Linear and nonlinear characteristics of heart rate time series in obesity and during weight-reduction surgery

    International Nuclear Information System (INIS)

    Alam, I; Morgan, J; Baxter, J; Lewis, M J

    2009-01-01

    Obesity is associated with abnormal cardiac regulation by the autonomic nervous system (ANS), this being reversed by weight loss. Bariatric (weight-reduction) surgery can induce substantial long-term weight reductions. This study compares the acute influence on ANS control of two different types of bariatric surgery involving laparascopic and open procedures. To distinguish between the cardiac influences of surgery and obesity, we perform the same analysis for laparascopic surgery in non-obese patients. Eight morbidly obese and five non-obese patients underwent surgery. Obese patients received either laparoscopic procedures (group A: n = 5, BMI = 44.3 ± 2.7 kg m 2 ) or open procedures (group B: n = 3, BMI = 55.2 ± 4.5 kg m 2 ) and non-obese patients received a laparoscopic procedure (group C: n = 5, BMI = 30.8 ± 5.8 kg m −2 ). Holter ECG was recorded and heart rate variability (HRV) was quantified together with measures of complexity (sample entropy) and structure (Hurst coefficient, scaling coefficient) of the heart rate data. Multifractal characteristics of heart rate data, not previously reported for obese patients, are also quantified and interpreted. Mixed model ANOVA was used to assess the magnitudes of each quantified variable, with surgical group and perioperative time as main factors. HRV measures were influenced only during anaesthesia (LFn increase: p = 0.009; HFn decrease: p = 0.033) and did not discriminate between patient groups. Multifractality was the only characteristic of heart rate data that discriminated between patient groups, being significantly (p < 0.001) greater in non-obese (group C) compared with obese patients (groups A and B, who had similar multifractal properties). Multifractality was also enhanced during anaesthesia (p = 0.028) but did not differ for other stages. We conclude that obesity per se rather than response to surgery is the cause of reduced multifractality. Reduced multifractality in obesity might reflect a diminished

  3. Improved Linear Cryptanalysis of Reduced-Round SIMON-32 and SIMON-48

    DEFF Research Database (Denmark)

    Abdelraheem, Mohamed Ahmed; Alizadeh, Javad; Alkhzaimi, Hoda A.

    2015-01-01

    In this paper we analyse two variants of SIMON family of light-weight block ciphers against variants of linear cryptanalysis and present the best linear cryptanalytic results on these variants of reducedround SIMON to date. We propose a time-memory trade-off method that finds differential/ linear...

  4. Evaluation of Body Weight and Other Linear Parameters of Marshall ...

    African Journals Online (AJOL)

    SH

    records of Marshall Broiler chickens to be more alike is low. Repeatability and variance ... the feed efficiency as well as performance ... Body weight is regarded as a function of frame work or size of the ... an animal‟s life time. ... Teaching and Research Farm, Ladoke. Akintola ... measured with a weighing balance calibrated ...

  5. Linear Viscoelasticity of Spherical SiO 2 Nanoparticle-Tethered Poly(butyl acrylate) Hybrids

    KAUST Repository

    Goel, Vivek; Pietrasik, Joanna; Matyjaszewski, Krzysztof; Krishnamoorti, Ramanan

    2010-01-01

    The melt state linear viscoelastic properties of spherical silica nanoparticles with grafted poly(n-butyl acrylate) chains of varying molecular weight were probed using linear small amplitude dynamic oscillatory measurements and complementary linear stress relaxation measurements. While the pure silica-tethered-polymer hybrids with no added homopolymer exhibit solid-like response, addition of matched molecular weight free matrix homopolymer chains to this hybrid, at low concentrations of added homopolymer, maintains the solid-like response with a lowered modulus that can be factored into a silica concentration dependence and a molecular weight dependence. While the silica concentration dependence of the modulus is strong, the dependence on molecular weight is weak. On the other hand, increasing the amount of added homopolymer changes the viscoelastic response to that of a liquid with a relaxation time that scales exponentially with hybrid concentration. © 2010 American Chemical Society.

  6. Linear Viscoelasticity of Spherical SiO 2 Nanoparticle-Tethered Poly(butyl acrylate) Hybrids

    KAUST Repository

    Goel, Vivek

    2010-12-01

    The melt state linear viscoelastic properties of spherical silica nanoparticles with grafted poly(n-butyl acrylate) chains of varying molecular weight were probed using linear small amplitude dynamic oscillatory measurements and complementary linear stress relaxation measurements. While the pure silica-tethered-polymer hybrids with no added homopolymer exhibit solid-like response, addition of matched molecular weight free matrix homopolymer chains to this hybrid, at low concentrations of added homopolymer, maintains the solid-like response with a lowered modulus that can be factored into a silica concentration dependence and a molecular weight dependence. While the silica concentration dependence of the modulus is strong, the dependence on molecular weight is weak. On the other hand, increasing the amount of added homopolymer changes the viscoelastic response to that of a liquid with a relaxation time that scales exponentially with hybrid concentration. © 2010 American Chemical Society.

  7. Birth weight, breast cancer and the potential mediating hormonal environment.

    Directory of Open Access Journals (Sweden)

    Radek Bukowski

    Full Text Available Previous studies have shown that woman's risk of breast cancer in later life is associated with her infants birth weights. The objective of this study was to determine if this association is independent of breast cancer risk factors, mother's own birth weight and to evaluate association between infants birth weight and hormonal environment during pregnancy. Independent association would have implications for understanding the mechanism, but also for prediction and prevention of breast cancer.Risk of breast cancer in relation to a first infant's birth weight, mother's own birth weight and breast cancer risk factors were evaluated in a prospective cohort of 410 women in the Framingham Study. Serum concentrations of estriol (E3, anti-estrogen alpha-fetoprotein (AFP, and pregnancy-associated plasma protein-A (PAPP-A were measured in 23,824 pregnant women from a separate prospective cohort, the FASTER trial. During follow-up (median, 14 years 31 women (7.6% were diagnosed with breast cancer. Women with large birth weight infants (in the top quintile had a higher breast cancer risk compared to other women (hazard ratio (HR, 2.5; 95% confidence interval (CI, 1.2-5.2; P = 0.012. The finding was not affected by adjustment for birth weight of the mother and traditional breast cancer risk factors (adjusted HR, 2.5; 95% CI, 1.2-5.6; P = 0.021. An infant's birth weight had a strong positive relationship with the mother's serum E3/AFP ratio and PAPP-A concentration during pregnancy. Adjustment for breast cancer risk factors did not have a material effect on these relationships.Giving birth to an infant with high birth weight was associated with increased breast cancer risk in later life, independently of mother's own birth weight and breast cancer risk factors and was also associated with a hormonal environment during pregnancy favoring future breast cancer development and progression.

  8. A model for the determination of the nominal potential for a linear accelerator

    International Nuclear Information System (INIS)

    Gutt, F.; Silva, P.; Guerrero, R.; Diaz, J.; Colmenares, J.

    1998-01-01

    The objective of the present work is to find a physical mathematical model based on the reason of the dose percentages at 10 and 20 cm depth, at 100 cm DFS and a 10 x 10 cm 2 field. It was utilized literature data of new manufactured accelerators and those are in use in hospitals, which allow to prove the model under different conditions. Our objective consists only to obtain a model that verifies the nominal potential for a linear accelerator, but without pretending that such a model to be used to calculate any one factor to determination of absorbed dose. (Author)

  9. Association between gestational weight gain according to body mass index and postpartum weight in a large cohort of Danish women.

    Science.gov (United States)

    Rode, Line; Kjærgaard, Hanne; Ottesen, Bent; Damm, Peter; Hegaard, Hanne K

    2012-02-01

    Our aim was to investigate the association between gestational weight gain (GWG) and postpartum weight retention (PWR) in pre-pregnancy underweight, normal weight, overweight or obese women, with emphasis on the American Institute of Medicine (IOM) recommendations. We performed secondary analyses on data based on questionnaires from 1,898 women from the "Smoke-free Newborn Study" conducted 1996-1999 at Hvidovre Hospital, Denmark. Relationship between GWG and PWR was examined according to BMI as a continuous variable and in four groups. Association between PWR and GWG according to IOM recommendations was tested by linear regression analysis and the association between PWR ≥ 5 kg (11 lbs) and GWG by logistic regression analysis. Mean GWG and mean PWR were constant for all BMI units until 26-27 kg/m(2). After this cut-off mean GWG and mean PWR decreased with increasing BMI. Nearly 40% of normal weight, 60% of overweight and 50% of obese women gained more than recommended during pregnancy. For normal weight and overweight women with GWG above recommendations the OR of gaining ≥ 5 kg (11 lbs) 1-year postpartum was 2.8 (95% CI 2.0-4.0) and 2.8 (95% CI 1.3-6.2, respectively) compared to women with GWG within recommendations. GWG above IOM recommendations significantly increases normal weight, overweight and obese women's risk of retaining weight 1 year after delivery. Health personnel face a challenge in prenatal counseling as 40-60% of these women gain more weight than recommended for their BMI. As GWG is potentially modifiable, our study should be followed by intervention studies focusing on GW.

  10. Tests of potential functional barriers for laminated multilayer food packages. Part II: Medium molecular weight permeants.

    Science.gov (United States)

    Simal-Gándara, J; Sarria-Vidal, M; Rijk, R

    2000-09-01

    Experiments were performed to characterize the kinetics of the permeation of different medium molecular weight model permeants: bisphenol A, warfarin and anthracene, from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick orientated polypropylene--OPP) into the food simulants olive oil and 3% (w/v) acetic acid. The characterization of permeation kinetics generally observed the permeation models previously reported to explain the experimental permeation results obtained for a low molecular weight group of model permeants. In general, the model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, (b) their subsequent steady-state permeation rates, and (c) their partition between liquid paraffin and the OPP membrane.

  11. The Potential Role of Yogurt in Weight Management and Prevention of Type 2 Diabetes.

    Science.gov (United States)

    Panahi, Shirin; Tremblay, Angelo

    2016-01-01

    Yogurt is a semisolid fermented milk product that originated centuries ago and is viewed as an essential food and important source of nutrients in the diet of humans. Over the last 30 years, overweight and obesity have become characteristic of Western and developing countries, which has led to deleterious health outcomes, including cardiovascular disease, type 2 diabetes, hypertension, and other chronic conditions. Recent epidemiological and clinical evidence suggests that yogurt is involved in the control of body weight and energy homeostasis and may play a role in reducing the risk for type 2 diabetes partly via the replacement of less healthy foods in the diet, its food matrix, the effect of specific nutrients such as calcium and protein on appetite control and glycemia, and alteration in gut microbiota. This review will discuss the specific properties that make yogurt a unique food among the dairy products, epidemiological and clinical evidence supporting yogurt's role in body weight, energy balance, and type 2 diabetes, including its potential mechanisms of action and gaps that need to be explored. Key teaching points • Several epidemiological and clinical studies have suggested a beneficial effect of yogurt consumption in the control of body weight and energy homeostasis, although this remains controversial. • Yogurt possesses unique properties, including its nutritional composition; lactic acid bacteria, which may affect gut microbiota; and food matrix, which may have a potential role in appetite and glycemic control. • Potential mechanisms of action of yogurt include an increase in body fat loss, decrease in food intake and increase in satiety, decrease in glycemic and insulin response, altered gut hormone response, replacement of less healthy foods, and altered gut microbiota. • The relative energy and nutrient content and contribution of a standard portion of yogurt to the overall diet suggest that the percentage daily intake of these nutrients

  12. "Accelerated Perceptron": A Self-Learning Linear Decision Algorithm

    OpenAIRE

    Zuev, Yu. A.

    2003-01-01

    The class of linear decision rules is studied. A new algorithm for weight correction, called an "accelerated perceptron", is proposed. In contrast to classical Rosenblatt's perceptron this algorithm modifies the weight vector at each step. The algorithm may be employed both in learning and in self-learning modes. The theoretical aspects of the behaviour of the algorithm are studied when the algorithm is used for the purpose of increasing the decision reliability by means of weighted voting. I...

  13. Scalar-tensor linear inflation

    Energy Technology Data Exchange (ETDEWEB)

    Artymowski, Michał [Institute of Physics, Jagiellonian University, Łojasiewicza 11, 30-348 Kraków (Poland); Racioppi, Antonio, E-mail: Michal.Artymowski@uj.edu.pl, E-mail: Antonio.Racioppi@kbfi.ee [National Institute of Chemical Physics and Biophysics, Rävala 10, 10143 Tallinn (Estonia)

    2017-04-01

    We investigate two approaches to non-minimally coupled gravity theories which present linear inflation as attractor solution: a) the scalar-tensor theory approach, where we look for a scalar-tensor theory that would restore results of linear inflation in the strong coupling limit for a non-minimal coupling to gravity of the form of f (φ) R /2; b) the particle physics approach, where we motivate the form of the Jordan frame potential by loop corrections to the inflaton field. In both cases the Jordan frame potentials are modifications of the induced gravity inflationary scenario, but instead of the Starobinsky attractor they lead to linear inflation in the strong coupling limit.

  14. CT energy weighting in the presence of scatter and limited energy resolution

    International Nuclear Information System (INIS)

    Schmidt, Taly Gilat

    2010-01-01

    Purpose: Energy-resolved CT has the potential to improve the contrast-to-noise ratio (CNR) through optimal weighting of photons detected in energy bins. In general, optimal weighting gives higher weight to the lower energy photons that contain the most contrast information. However, low-energy photons are generally most corrupted by scatter and spectrum tailing, an effect caused by the limited energy resolution of the detector. This article first quantifies the effects of spectrum tailing on energy-resolved data, which may also be beneficial for material decomposition applications. Subsequently, the combined effects of energy weighting, spectrum tailing, and scatter are investigated through simulations. Methods: The study first investigated the effects of spectrum tailing on the estimated attenuation coefficients of homogeneous slab objects. Next, the study compared the CNR and artifact performance of images simulated with varying levels of scatter and spectrum tailing effects, and reconstructed with energy integrating, photon-counting, and two optimal linear weighting methods: Projection-based and image-based weighting. Realistic detector energy-response functions were simulated based on a previously proposed model. The energy-response functions represent the probability that a photon incident on the detector at a particular energy will be detected at a different energy. Realistic scatter was simulated with Monte Carlo methods. Results: Spectrum tailing resulted in a negative shift in the estimated attenuation coefficient of slab objects compared to an ideal detector. The magnitude of the shift varied with material composition, increased with material thickness, and decreased with photon energy. Spectrum tailing caused cupping artifacts and CT number inaccuracies in images reconstructed with optimal energy weighting, and did not impact images reconstructed with photon counting weighting. Spectrum tailing did not significantly impact the CNR in reconstructed images

  15. Cell-centered particle weighting algorithm for PIC simulations in a non-uniform 2D axisymmetric mesh

    Science.gov (United States)

    Araki, Samuel J.; Wirz, Richard E.

    2014-09-01

    Standard area weighting methods for particle-in-cell simulations result in systematic errors on particle densities for a non-uniform mesh in cylindrical coordinates. These errors can be significantly reduced by using weighted cell volumes for density calculations. A detailed description on the corrected volume calculations and cell-centered weighting algorithm in a non-uniform mesh is provided. The simple formulas for the corrected volume can be used for any type of quadrilateral and/or triangular mesh in cylindrical coordinates. Density errors arising from the cell-centered weighting algorithm are computed for radial density profiles of uniform, linearly decreasing, and Bessel function in an adaptive Cartesian mesh and an unstructured mesh. For all the density profiles, it is shown that the weighting algorithm provides a significant improvement for density calculations. However, relatively large density errors may persist at outermost cells for monotonically decreasing density profiles. A further analysis has been performed to investigate the effect of the density errors in potential calculations, and it is shown that the error at the outermost cell does not propagate into the potential solution for the density profiles investigated.

  16. On P-weight and P-distance inequalities

    DEFF Research Database (Denmark)

    Britz, Thomas Johann

    2006-01-01

    Jang and Park asked in [On a MacWilliams type identity and a perfectness for a binary linear (n, n - 1, j)-poset code, Discrete Math. 265 (2003) 85-104] whether, for each poset P = {l...., n}, the P-weights and P-distances satisfy the inequalities w(P)(x) - w(P)(y)......Jang and Park asked in [On a MacWilliams type identity and a perfectness for a binary linear (n, n - 1, j)-poset code, Discrete Math. 265 (2003) 85-104] whether, for each poset P = {l...., n}, the P-weights and P-distances satisfy the inequalities w(P)(x) - w(P)(y)...

  17. On the non-linear dynamics of potential relaxation oscillations in bounded plasmas

    International Nuclear Information System (INIS)

    Krssak, M.; Skalny, J.D.; Gyergyek, T.; Cercek, M.

    2007-01-01

    Plasma in a 1-dimensional diode is studied theoretically and the computer simulations are used for verification of the theoretical model. When collector in the diode is biased positively, a double-layer is created in the system and consequently, we are able to observe oscillations of the potential, density and other plasma parameters. When external periodic forcing is applied, spectra of these oscillations are changed and effects of synchronisation and periodic pulling can be observed. Both of these effects are of non-linear nature and a good explanation is found using the analogy with Van der Pol oscillators. Following [1] and [2] approximate analytical solutions are found and then compared with computer simulations obtained using a 1-dimensional particle-in-cell code XPDP1. (author)

  18. On the classical theory of ordinary linear differential equations of the second order and the Schroedinger equation for power law potentials

    International Nuclear Information System (INIS)

    Lima, M.L.; Mignaco, J.A.

    1983-01-01

    The power law potentials in the Schroedinger equation solved recently are shown to come from the classical treatment of the singularities of a linear, second order differential equation. This allows to enlarge the class of solvable power law potentials. (Author) [pt

  19. The linear ordering problem: an algorithm for the optimal solution ...

    African Journals Online (AJOL)

    In this paper we describe and implement an algorithm for the exact solution of the Linear Ordering problem. Linear Ordering is the problem of finding a linear order of the nodes of a graph such that the sum of the weights which are consistent with this order is as large as possible. It is an NP - Hard combinatorial optimisation ...

  20. Residential proximity to major roads and placenta/birth weight ratio.

    Science.gov (United States)

    Yorifuji, Takashi; Naruse, Hiroo; Kashima, Saori; Murakoshi, Takeshi; Tsuda, Toshihide; Doi, Hiroyuki; Kawachi, Ichiro

    2012-01-01

    Exposure to air pollution has been demonstrated to increase the risk of preterm birth and low birth weight. We examined whether proximity to major roads (as a marker of exposure to air pollution) is associated with increased placenta/birth weight ratio (as a biomarker of the placental transport function). Data on parental characteristics and birth outcomes were extracted from the database maintained by a major hospital in Shizuoka Prefecture, Japan. We restricted the analysis to mothers who delivered liveborn single births from 1997 to 2008 (n = 14,189). Using geocoded residential information, each birth was classified according to proximity to major roads. We examined the association between proximity to major roads and the placenta/birth weight ratio, using multiple linear regression. Proximity to major roads was associated with higher placenta/birth weight ratio. After adjusting for potential confounders, living within 200 m of a major road increased the ratio by 0.48% (95% CI = 0.15 to 0. 80). In addition, proximity to major roads was associated with lower placenta weight and birth weight. These observed associations were stronger among participants living closer to major roads. Exposure to traffic-related air pollution is associated with higher placenta/birth weight ratio. Impaired placental oxygen and nutrient transport function might be a mechanism for explaining the observed association between air pollution and low birth weight as well as preterm birth. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. Linear signal hyperintensity adjacent to the subchondral bone plate at the knee on T2-weighted fat-saturated sequences: imaging aspects and association with structural lesions

    Energy Technology Data Exchange (ETDEWEB)

    Gondim Teixeira, Pedro Augusto; Balaj, Clemence [CHU Hopital Central, Service D' Imagerie Guilloz, Nancy (France); Universite de Lorraine, IADI, UMR S 947, Nancy (France); Marie, Beatrice [CHU Hopital Central, Service d' Anatomo-Pathologie, Nancy (France); Lecocq, Sophie; Louis, Matthias; Blum, Alain [CHU Hopital Central, Service D' Imagerie Guilloz, Nancy (France); Braun, Marc [CHU Hopital Central, Service de Neuroradiologie, Nancy (France)

    2014-11-15

    To describe the association between linear T2 signal abnormalities in the subchondral bone and structural knee lesions. MR studies of patients referred for the evaluation of knee pain were retrospectively evaluated and 133 of these patients presented bone marrow edema pattern (BMEP) (study group) and while 61 did not (control group). The presence of linear anomalies of the subchondral bone on T2-weighted fat-saturated sequences was evaluated. The findings were correlated to the presence of structural knee lesions and to the duration of the patient's symptoms. Histologic analysis of a cadaveric specimen was used for anatomic correlation. Linear T2 hyperintensities at the subchondral bone were present in 41 % of patients with BMEP. None of the patients in the control group presented this sign. When a subchondral linear hyperintensity was present, the prevalence of radial or root tears was high and that of horizontal tears was low (71.4 and 4.8 %, respectively). Sixty-nine percent of the patients with a subchondral insufficiency fracture presented a subchondral linear hyperintensity. It was significantly more prevalent in patients with acute or sub-acute symptoms (p < 0.0001). The studied linear T2 hyperintensity is located at the subchondral spongiosa and can be secondary to local or distant joint injuries. Its presence should evoke acute and sub-acute knee injuries. This sign is closely related to subchondral insufficiency fractures and meniscal tears with a compromise in meniscal function. (orig.)

  2. Adult weight gain and colorectal adenomas-a systematic review and meta-analysis.

    Science.gov (United States)

    Schlesinger, S; Aleksandrova, K; Abar, L; Vieria, A R; Vingeliene, S; Polemiti, E; Stevens, C A T; Greenwood, D C; Chan, D S M; Aune, D; Norat, T

    2017-06-01

    Colorectal adenomas are known as precursors for the majority of colorectal carcinomas. While weight gain during adulthood has been identified as a risk factor for colorectal cancer, the association is less clear for colorectal adenomas. We conducted a systematic review and meta-analysis to quantify the evidence on this association. We searched Medline up to September 2016 to identify observational (prospective, cross-sectional and retrospective) studies on weight gain during adulthood and colorectal adenoma occurrence and recurrence. We conducted meta-analysis on high weight gain versus stable weight, linear and non-linear dose-response meta-analyses to analyze the association. Summary odds ratios (OR) and 95% confidence intervals (95% CI) were estimated using a random effects model. For colorectal adenoma occurrence, the summary OR was 1.39 (95% CI: 1.17-1.65; I2: 43%, N = 9 studies, cases = 5507) comparing high (midpoint: 17.4 kg) versus stable weight gain during adulthood and with each 5 kg weight gain the odds increased by 7% (2%-11%; I2: 65%, N = 7 studies). Although there was indication of non-linearity (Pnon-linearity firm conclusions. Even a small amount of adult weight gain was related to a higher odds of colorectal adenoma occurrence. Our findings add to the benefits of weight control in adulthood regarding colorectal adenoma occurrence, which might be relevant for early prevention of colorectal cancer. © The Author 2017. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  3. Exact potential and scattering amplitudes from the tachyon non-linear β -function

    International Nuclear Information System (INIS)

    Coletti, E.; Forini, V.; Nardelli, G.; Orselli, M.; Grignani, G.

    2004-01-01

    We compute, on the disk, the non-linear tachyon β-function, β T , of the open bosonic string theory. β T is determined both in an expansion to the third power of the field and to all orders in derivatives and in an expansion to any power of the tachyon field in the leading order in derivatives. We construct the Witten-Shatashvili (WS) space-time effective action S and prove that it has a very simple universal form in terms of the renormalized tachyon field and β T . The expression for S is well suited to studying both processes that are far off-shell, such as tachyon condensation, and close to the mass-shell, such as perturbative on-shell amplitudes. We evaluate S in a small derivative expansion, providing the exact tachyon potential. The normalization of S is fixed by requiring that the field redefinition that maps S into the tachyon effective action derived from the cubic string field theory is regular on-shell. The normalization factor is in precise agreement with the one required for verifying all the conjectures on tachyon condensation. The coordinates in the space of couplings in which the tachyon β-function is non linear are the most appropriate to study RG fixed points that can be interpreted as solitons of S, i.e. D-branes. (author)

  4. Weighted straight skeletons in the plane.

    Science.gov (United States)

    Biedl, Therese; Held, Martin; Huber, Stefan; Kaaser, Dominik; Palfrader, Peter

    2015-02-01

    We investigate weighted straight skeletons from a geometric, graph-theoretical, and combinatorial point of view. We start with a thorough definition and shed light on some ambiguity issues in the procedural definition. We investigate the geometry, combinatorics, and topology of faces and the roof model, and we discuss in which cases a weighted straight skeleton is connected. Finally, we show that the weighted straight skeleton of even a simple polygon may be non-planar and may contain cycles, and we discuss under which restrictions on the weights and/or the input polygon the weighted straight skeleton still behaves similar to its unweighted counterpart. In particular, we obtain a non-procedural description and a linear-time construction algorithm for the straight skeleton of strictly convex polygons with arbitrary weights.

  5. Quantification of endocrine disruptors and pesticides in water by gas chromatography-tandem mass spectrometry. Method validation using weighted linear regression schemes.

    Science.gov (United States)

    Mansilha, C; Melo, A; Rebelo, H; Ferreira, I M P L V O; Pinho, O; Domingues, V; Pinho, C; Gameiro, P

    2010-10-22

    A multi-residue methodology based on a solid phase extraction followed by gas chromatography-tandem mass spectrometry was developed for trace analysis of 32 compounds in water matrices, including estrogens and several pesticides from different chemical families, some of them with endocrine disrupting properties. Matrix standard calibration solutions were prepared by adding known amounts of the analytes to a residue-free sample to compensate matrix-induced chromatographic response enhancement observed for certain pesticides. Validation was done mainly according to the International Conference on Harmonisation recommendations, as well as some European and American validation guidelines with specifications for pesticides analysis and/or GC-MS methodology. As the assumption of homoscedasticity was not met for analytical data, weighted least squares linear regression procedure was applied as a simple and effective way to counteract the greater influence of the greater concentrations on the fitted regression line, improving accuracy at the lower end of the calibration curve. The method was considered validated for 31 compounds after consistent evaluation of the key analytical parameters: specificity, linearity, limit of detection and quantification, range, precision, accuracy, extraction efficiency, stability and robustness. Copyright © 2010 Elsevier B.V. All rights reserved.

  6. Birth weight, breast cancer and the potential mediating hormonal environment.

    LENUS (Irish Health Repository)

    Bukowski, Radek

    2012-01-01

    Previous studies have shown that woman\\'s risk of breast cancer in later life is associated with her infants birth weights. The objective of this study was to determine if this association is independent of breast cancer risk factors, mother\\'s own birth weight and to evaluate association between infants birth weight and hormonal environment during pregnancy. Independent association would have implications for understanding the mechanism, but also for prediction and prevention of breast cancer.

  7. The associations between adult body composition and abdominal adiposity outcomes, and relative weight gain and linear growth from birth to age 22 in the Birth to Twenty Plus cohort, South Africa.

    Directory of Open Access Journals (Sweden)

    Alessandra Prioreschi

    Full Text Available The growing prevalence of overweight and obesity in low- or middle-income countries precipitates the need to examine early life predictors of adiposity.To examine growth trajectories from birth, and associations with adult body composition in the Birth to Twenty Plus Cohort, Soweto, South Africa.Complete data at year 22 was available for 1088 participants (536 males and 537 females. Conditional weight and height indices were generated indicative of relative rate of growth between years 0-2, 2-5, 5-8, 8-18, and 18-22. Whole body composition was measured at year 22 (range 21-25 years using dual energy x-ray absorptiometry (DXA. Total fat free soft tissue mass (FFSTM, fat mass, and abdominal visceral adipose tissue (VAT and subcutaneous adipose tissue (SAT were recorded.Birth weight was positively associated with FFSTM and fat mass at year 22 (β = 0.11, p<0.01 and β = 0.10, p<0.01 respectively. Relative weight gain from birth to year 22 was positively associated with FFSTM, fat mass, VAT, and SAT at year 22. Relative linear growth from birth to year 22 was positively associated with FFSTM at year 22. Relative linear growth from birth to year 2 was positively associated with VAT at year 22. Being born small for gestational age and being stunted at age 2 years were inversely associated with FFSTM at year 22.The importance of optimal birth weight and growth tempos during early life for later life body composition, and the detrimental effects of pre- and postnatal growth restriction are clear; yet contemporary weight-gain most strongly predicted adult body composition. Thus interventions should target body composition trajectories during childhood and prevent excessive weight gain in early adulthood.

  8. Calculation of the masses of the ground-state baryons as a test of the hypothesis that the potential is a combination of a Coulomb and a linear potential

    International Nuclear Information System (INIS)

    Kalman, C.S.; Tran, B.; Hall, R.L.

    1987-01-01

    The hypothesis that the interquark potential in the baryon is the sum of a Coulomb and a linear potential is evalutated in terms of the model of Isgur and Karl as modified by Kalman, Hal and Misra. Six parameters are used to fit the eight ground-state baryon masses. The closeness of the predicted values to the experimental values verifies the hypothesis

  9. Object matching using a locally affine invariant and linear programming techniques.

    Science.gov (United States)

    Li, Hongsheng; Huang, Xiaolei; He, Lei

    2013-02-01

    In this paper, we introduce a new matching method based on a novel locally affine-invariant geometric constraint and linear programming techniques. To model and solve the matching problem in a linear programming formulation, all geometric constraints should be able to be exactly or approximately reformulated into a linear form. This is a major difficulty for this kind of matching algorithm. We propose a novel locally affine-invariant constraint which can be exactly linearized and requires a lot fewer auxiliary variables than other linear programming-based methods do. The key idea behind it is that each point in the template point set can be exactly represented by an affine combination of its neighboring points, whose weights can be solved easily by least squares. Errors of reconstructing each matched point using such weights are used to penalize the disagreement of geometric relationships between the template points and the matched points. The resulting overall objective function can be solved efficiently by linear programming techniques. Our experimental results on both rigid and nonrigid object matching show the effectiveness of the proposed algorithm.

  10. Stochastic Least-Squares Petrov--Galerkin Method for Parameterized Linear Systems

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kookjin [Univ. of Maryland, College Park, MD (United States). Dept. of Computer Science; Carlberg, Kevin [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Elman, Howard C. [Univ. of Maryland, College Park, MD (United States). Dept. of Computer Science and Inst. for Advanced Computer Studies

    2018-03-29

    Here, we consider the numerical solution of parameterized linear systems where the system matrix, the solution, and the right-hand side are parameterized by a set of uncertain input parameters. We explore spectral methods in which the solutions are approximated in a chosen finite-dimensional subspace. It has been shown that the stochastic Galerkin projection technique fails to minimize any measure of the solution error. As a remedy for this, we propose a novel stochatic least-squares Petrov--Galerkin (LSPG) method. The proposed method is optimal in the sense that it produces the solution that minimizes a weighted $\\ell^2$-norm of the residual over all solutions in a given finite-dimensional subspace. Moreover, the method can be adapted to minimize the solution error in different weighted $\\ell^2$-norms by simply applying a weighting function within the least-squares formulation. In addition, a goal-oriented seminorm induced by an output quantity of interest can be minimized by defining a weighting function as a linear functional of the solution. We establish optimality and error bounds for the proposed method, and extensive numerical experiments show that the weighted LSPG method outperforms other spectral methods in minimizing corresponding target weighted norms.

  11. Relationship between impulsivity, snack consumption and children's weight.

    Directory of Open Access Journals (Sweden)

    Eline W M Scholten

    Full Text Available Childhood overweight is a public health problem associated with psychosocial and physical problems. Personality traits, such as impulsivity, may contribute to the development of overweight.This study examines 1 the association between general impulsivity traits (reward sensitivity and disinhibition and children's weight, 2 the association between impulsivity traits and unhealthy snack consumption, and 3 the potential mediating role of unhealthy snack consumption in the relationship between impulsivity traits and children's weight.Included were 1,377 parent-child dyads participating in the IVO Nutrition and Physical Activity Child cohorT (INPACT. Children had a mean age of 10 years. Parents completed a questionnaire to measure children's unhealthy snack consumption. Children completed a door-opening task to assess reward sensitivity and completed a questionnaire to measure disinhibition. Children's height and weight were measured to calculate their BMI z-scores. Cross-sectional linear regression analyses were performed to test the associations.Disinhibition was positively associated with unhealthy snack consumption but not with BMI z-scores. Reward sensitivity was not related to unhealthy snack consumption or to BMI z-scores.No evidence was found for a mediating effect of unhealthy snack consumption in the relation between impulsivity traits and children's weight. However, disinhibition appears to have a negative influence on children's unhealthy snack consumption. Future research focusing on food-related impulsivity in addition to general impulsivity will provide additional insight into factors that influence children's unhealthy snack consumption and weight.

  12. Relationship between impulsivity, snack consumption and children's weight.

    Science.gov (United States)

    Scholten, Eline W M; Schrijvers, Carola T M; Nederkoorn, Chantal; Kremers, Stef P J; Rodenburg, Gerda

    2014-01-01

    Childhood overweight is a public health problem associated with psychosocial and physical problems. Personality traits, such as impulsivity, may contribute to the development of overweight. This study examines 1) the association between general impulsivity traits (reward sensitivity and disinhibition) and children's weight, 2) the association between impulsivity traits and unhealthy snack consumption, and 3) the potential mediating role of unhealthy snack consumption in the relationship between impulsivity traits and children's weight. Included were 1,377 parent-child dyads participating in the IVO Nutrition and Physical Activity Child cohorT (INPACT). Children had a mean age of 10 years. Parents completed a questionnaire to measure children's unhealthy snack consumption. Children completed a door-opening task to assess reward sensitivity and completed a questionnaire to measure disinhibition. Children's height and weight were measured to calculate their BMI z-scores. Cross-sectional linear regression analyses were performed to test the associations. Disinhibition was positively associated with unhealthy snack consumption but not with BMI z-scores. Reward sensitivity was not related to unhealthy snack consumption or to BMI z-scores. No evidence was found for a mediating effect of unhealthy snack consumption in the relation between impulsivity traits and children's weight. However, disinhibition appears to have a negative influence on children's unhealthy snack consumption. Future research focusing on food-related impulsivity in addition to general impulsivity will provide additional insight into factors that influence children's unhealthy snack consumption and weight.

  13. Ozonation of humic substances: Effects on molecular weight distributions of organic carbon and trihalomethane formation potential

    International Nuclear Information System (INIS)

    Amy, G.L.; Kuo, C.J.; Sierka, R.A.

    1988-01-01

    Four different sources of humic substances were studied to determine the effects of ozonation on molecular weight distributions, based on dissolved organic carbon (DOC) and trihalomethane formation potential (THMFP). Solutions of two soil-derived fulvic acids and a one soil-derived humic acid, as well as dissolved organic matter (DOM) associated with a natural water source were studied. Both gel permeation chromatography (GPC) and ultrafiltration (UF) were employed to define apparent molecular weight (AMW). Applied ozone doses ranged from 2.0 to 2.5 mg O 3 /mg DOC. Overall samples of untreated and ozonated waters, as well as individual molecular weight fractions, were characterized according to DOC, uv absorbance, and THMFP. Ozonation resulted in a significant disappearance of higher AMW material with a corresponding increase in lower AMW material. Although little overall reduction in DOC concentration was observed, significant overall reductions in UV absorbance and THMFP levels were observed

  14. Weight training, aerobic physical activities, and long-term waist circumference change in men.

    Science.gov (United States)

    Mekary, Rania A; Grøntved, Anders; Despres, Jean-Pierre; De Moura, Leandro Pereira; Asgarzadeh, Morteza; Willett, Walter C; Rimm, Eric B; Giovannucci, Edward; Hu, Frank B

    2015-02-01

    Findings on weight training and waist circumference (WC) change are controversial. This study examined prospectively whether weight training, moderate to vigorous aerobic activity (MVAA), and replacement of one activity for another were associated with favorable changes in WC and body weight (BW). Physical activity, WC, and BW were reported in 1996 and 2008 in a cohort of 10,500 healthy U.S. men in the Health Professionals Follow-up Study. Multiple linear regression models (partition/substitution) to assess these associations were used. After adjusting for potential confounders, a significant inverse dose-response relationship between weight training and WC change (P-trend weight training (-0.67 cm, 95% CI -0.93, -0.41) than for MVAA (-0.33 cm, 95% CI -0.40, -0.27), other activities (-0.16 cm, 95% CI -0.28, -0.03), or TV watching (0.08 cm, 95% CI 0.05, 0.12). Substituting 20 min/day of weight training for any other discretionary activity had the strongest inverse association with WC change. MVAA had the strongest inverse association with BW change (-0.23 kg, 95% CI -0.29, -0.17). Among various activities, weight training had the strongest association with less WC increase. Studies on frequency/volume of weight training and WC change are warranted. © 2014 The Obesity Society.

  15. Caregiver perceptions of children's linear growth in Bangladesh: a qualitative analysis.

    Science.gov (United States)

    Hossain, Muttaquina; Ickes, Scott; Rice, Lauren; Ritter, Gaelen; Naila, Nurun Nahar; Zia, Tasnia; Nahar, Baitun; Mahfuz, Mustafa; Denno, Donna M; Ahmed, Tahmeed; Walson, Judd

    2018-03-26

    To understand caregivers' perceptions of children's linear growth and to identify the cultural meanings and perceptions of risk associated with poor height attainment. Three investigators from Bangladesh conducted twelve focus group discussions. The study was conducted in rural and slum settings in Bangladesh. Participants included mothers and alternative caregivers (n 81) who were recruited by household screening. No eligible, recruited subjects refused participation. Caregivers reported limited experience with growth monitoring services from the health system. Caregivers mainly use visual cues and developmental milestones to understand if children are growing properly, and recognize that children normally experience both weight gain and linear growth with age. Mothers expressed concern over children's malnutrition and short stature, but did not discuss children's failure to attain a 'growth potential' or distinguish inherited short stature from stunting. Caregivers interpret the consequences of poor height attainment as primarily social and economic and cite few health risks. Linear growth interpretation is determined more by community norms than by guidance from nutrition programming or the health system. Interventions to prevent or reduce linear growth failure may be perceived to have limited value where appropriate linear growth in children is determined by comparison to peers and siblings. Such perceptions may be significant barriers to programmes addressing stunting prevention in settings where many children are stunted. Efforts to raise awareness about the risks of linear growth faltering may need to consider delivering messages to caregivers that emphasize the social and economic consequences of stunting.

  16. Extension of the linear nodal method to large concrete building calculations

    International Nuclear Information System (INIS)

    Childs, R.L.; Rhoades, W.A.

    1985-01-01

    The implementation of the linear nodal method in the TORT code is described, and the results of a mesh refinement study to test the effectiveness of the linear nodal and weighted diamond difference methods available in TORT are presented

  17. Effect of Exposure to Air Pollution on Placental Weight in Isfahan-Iran.

    Science.gov (United States)

    Ghasemi-Tehrani, Hatav; Fallah, Setare; Mozafarian, Nafiseh; Miranzadeh, Sareh; Sadeghi, Shokooh; Azidhak, Azam

    2017-06-01

    Objective: To determine the effect of Air Quality Index (AQI) in the first trimester of pregnancy on birth weight, placental weight, and the ratio of placental weight to the birth weight (pw-bw) in Isfahan. Materials and methods: This cross-sectional study was done on 312 consecutive pregnant women in Beheshti Hospital in Isfahan city in 2013. Information on air pollution was received from the Environmental department of Isfahan. Average exposure to air pollution in the first trimester of pregnancy was calculated for eachpregnant woman. In order to compare quantitative and qualitative variables, analysis of variance (ANOVA), and chi-square were applied. After that, the multiple linear regression analysis was used to assess the association the Air Quality Index (AQI) on birth weight, placental weight and the ratio of pw-bw. Potential confounders including age, baby gender, smoking of husband, maternal BMI, maternal occupation, and education and mother's residential area were considered. A statistical significant association were considered for P-value less than 0.05. Results: The findings showed that there is inverse relationship between exposure to air pollution and placental weight in the first trimester of pregnancy after controlling potential confounders (β = -2.57, p-value = 0.008). The inverse relationship between air pollution and the ratio of pw-bw was found. (β = -0.001, p-value = 0.002). Conclusion: The results of this study suggest that air pollution is associated with newborns' health which in turn is a warning alarm for considering some actions in both sides of reducing the air pollution and teaching the pregnant women about the adverse effects of air pollution on the pregnancy outcomes.

  18. Effect of Exposure to Air Pollution on Placental Weight in Isfahan-Iran

    Directory of Open Access Journals (Sweden)

    Hatav Ghasemi Tehrani

    2017-10-01

    Full Text Available Objective: To determine the effect of Air Quality Index (AQI in the first trimester of pregnancy on birth weight, placental weight, and the ratio of placental weight to the birth weight (pw-bw in Isfahan.Materials and methods: This cross-sectional study was done on 312 consecutive pregnant women in Beheshti Hospital in Isfahan city in 2013. Information on air pollution was received from the Environmental department of Isfahan. Average exposure to air pollution in the first trimester of pregnancy was calculated for eachpregnant woman. In order to compare quantitative and qualitative variables, analysis of variance (ANOVA, and chi-square were applied. After that, the multiple linear regression analysis was used to assess the association the Air Quality Index (AQI on birth weight, placental weight and the ratio of pw-bw. Potential confounders including age, baby gender, smoking of husband, maternal BMI, maternal occupation, and education and mother’s residential area were considered. A statistical significant association were considered for P-value less than 0.05.Results: The findings showed that there is inverse relationship between exposure to air pollution and placental weight in the first trimester of pregnancy after controlling potential confounders (β = -2.57, p-value = 0.008. The inverse relationship between air pollution and the ratio of pw-bw was found. (β = -0.001, p-value = 0.002.Conclusion: The results of this study suggest that air pollution is associated with newborns’ health which in turn is a warning alarm for considering some actions in both sides of reducing the air pollution and teaching the pregnant women about the adverse effects of air pollution on the pregnancy outcomes.

  19. Weighted thinned linear array design with the iterative FFT technique

    CSIR Research Space (South Africa)

    Du Plessis, WP

    2011-09-01

    Full Text Available techniques utilise simulated annealing [3]?[5], [10], mixed integer linear programming [7], genetic algorithms [9], and a hyrid approach combining a genetic algorithm and a local optimiser [8]. The iterative Fourier technique (IFT) developed by Keizer [2... algorithm being well- suited to obtaining low CTRs. Test problems from the literature are considered, and the results obtained with the IFT considerably exceed those achieved with other algorithms. II. DESCRIPTION OF THE ALGORITHM A flowchart describing...

  20. On the Inefficiency of Equilibria in Linear Bottleneck Congestion Games

    Science.gov (United States)

    de Keijzer, Bart; Schäfer, Guido; Telelis, Orestis A.

    We study the inefficiency of equilibrium outcomes in bottleneck congestion games. These games model situations in which strategic players compete for a limited number of facilities. Each player allocates his weight to a (feasible) subset of the facilities with the goal to minimize the maximum (weight-dependent) latency that he experiences on any of these facilities. We derive upper and (asymptotically) matching lower bounds on the (strong) price of anarchy of linear bottleneck congestion games for a natural load balancing social cost objective (i.e., minimize the maximum latency of a facility). We restrict our studies to linear latency functions. Linear bottleneck congestion games still constitute a rich class of games and generalize, for example, load balancing games with identical or uniformly related machines with or without restricted assignments.

  1. Mid-upper arm circumference in pregnant women and its relation to birth weight

    Directory of Open Access Journals (Sweden)

    Ricalde Anamaría E.

    1998-01-01

    Full Text Available OBJECTIVE: In order to determine the relationship between some maternal anthropometric indicators and birth weight, crown-heel length and newborn's head circumference, 92 pregnant women were followed through at the prenatal service of hospital in S. Paulo, Brazil. MATERIAL AND METHOD: The following variables were established for the mother: weight, height, mid-upper arm circumference, pre-pregnancy weight, gestational weight gain and Quetelet's index. For the newborn the following variables were recorded: birth weight, crown-heel length, head circumference and gestational age by Dubowitz's method. RESULTS: Significant associations were noted between gestational age and newborn variables. In addition, maternal mid-arm circumference (MUAC and pre-pregnancy weight were found to be positively correlated to birth weight (r=0.399; r=0.378, respectively. The multivariate linear regression shows that gestational age, mother's arm circumference and pre-pregnancy weight continue to be significant predictors of birth weight. On the other hand, only gestational age and mother's age was associated with crown-heel length. Similarly MUAC was significantly associated with crown-heel length (r= 0.306; P=0.0030. CONCLUSION: Maternal mid-upper arm circumference is a potential indicator of maternal nutritional status. It could be used in association with other anthropometric measurements, instead of pre-pregnancy weight, as an alternative indicator to assess women at risk of poor pregnancy outcome.

  2. Mid-upper arm circumference in pregnant women and its relation to birth weight

    Directory of Open Access Journals (Sweden)

    Anamaría E. Ricalde

    1998-04-01

    Full Text Available OBJECTIVE: In order to determine the relationship between some maternal anthropometric indicators and birth weight, crown-heel length and newborn's head circumference, 92 pregnant women were followed through at the prenatal service of hospital in S. Paulo, Brazil. MATERIAL AND METHOD: The following variables were established for the mother: weight, height, mid-upper arm circumference, pre-pregnancy weight, gestational weight gain and Quetelet's index. For the newborn the following variables were recorded: birth weight, crown-heel length, head circumference and gestational age by Dubowitz's method. RESULTS: Significant associations were noted between gestational age and newborn variables. In addition, maternal mid-arm circumference (MUAC and pre-pregnancy weight were found to be positively correlated to birth weight (r=0.399; r=0.378, respectively. The multivariate linear regression shows that gestational age, mother's arm circumference and pre-pregnancy weight continue to be significant predictors of birth weight. On the other hand, only gestational age and mother's age was associated with crown-heel length. Similarly MUAC was significantly associated with crown-heel length (r= 0.306; P=0.0030. CONCLUSION: Maternal mid-upper arm circumference is a potential indicator of maternal nutritional status. It could be used in association with other anthropometric measurements, instead of pre-pregnancy weight, as an alternative indicator to assess women at risk of poor pregnancy outcome.

  3. Culture media influenced laboratory outcomes but not neonatal birth weight in assisted reproductive technology.

    Science.gov (United States)

    Yin, Tai-lang; Zhang, Yi; Li, Sai-jiao; Zhao, Meng; Ding, Jin-li; Xu, Wang-ming; Yang, Jing

    2015-12-01

    Whether the type of culture media utilized in assisted reproductive technology has impacts on laboratory outcomes and birth weight of newborns in in-vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) was investigated. A total of 673 patients undergoing IVF/ICSI and giving birth to live singletons after fresh embryo transfer on day 3 from Jan. 1, 2010 to Dec. 31, 2012 were included. Three types of culture media were used during this period: Quinn's Advantage (QA), Single Step Medium (SSM), and Continuous Single Culture medium (CSC). Fertilization rate (FR), normal fertilization rate (NFR), cleavage rate (CR), normal cleavage rate (NCR), good-quality embryo rate (GQER) and neonatal birth weight were compared using one-way ANOVA and χ (2) tests. Multiple linear regression analysis was performed to determine the impact of culture media on laboratory outcomes and birth weight. In IVF cycles, GQER was significantly decreased in SSM medium group as compared with QA or CSC media groups (63.6% vs. 69.0% in QA; vs. 71.3% in CSC, P=0.011). In ICSI cycles, FR, NFR and CR were significantly lower in CSC medium group than in other two media groups. No significant difference was observed in neonatal birthweight among the three groups (P=0.759). Multiple linear regression analyses confirmed that the type of culture medium was correlated with FR, NFR, CR and GQER, but not with neonatal birth weight. The type of culture media had potential influences on laboratory outcomes but did not exhibit an impact on the birth weight of singletons in ART.

  4. [Association between hours of television watched, physical activity, sleep and excess weight among young adults].

    Science.gov (United States)

    Martínez-Moyá, María; Navarrete-Muñoz, Eva M; García de la Hera, Manuela; Giménez-Monzo, Daniel; González-Palacios, Sandra; Valera-Gran, Desirée; Sempere-Orts, María; Vioque, Jesús

    2014-01-01

    To explore the association between excess weight or body mass index (BMI) and the time spent watching television, self-reported physical activity and sleep duration in a young adult population. We analyzed cross-sectional baseline data of 1,135 participants (17-35 years old) from the project Dieta, salud y antropometría en población universitaria (Diet, Health and Anthrompmetric Variables in Univeristy Students). Information about time spent watching television, sleep duration, self-reported physical activity and self-reported height and weight was provided by a baseline questionnaire. BMI was calculated as kg/m(2) and excess of weight was defined as ≥25. We used multiple logistic regression to explore the association between excess weight (no/yes) and independent variables, and multiple linear regression for BMI. The prevalence of excess weight was 13.7% (11.2% were overweight and 2.5% were obese). A significant positive association was found between excess weight and a greater amount of time spent watching television. Participants who reported watching television >2h a day had a higher risk of excess weight than those who watched television ≤1h a day (OR=2.13; 95%CI: 1.37-3.36; p-trend: 0.002). A lower level of physical activity was associated with an increased risk of excess weight, although the association was statistically significant only in multiple linear regression (p=0.037). No association was observed with sleep duration. A greater number of hours spent watching television and lower physical activity were significantly associated with a higher BMI in young adults. Both factors are potentially modifiable with preventive strategies. Copyright © 2013 SESPAS. Published by Elsevier Espana. All rights reserved.

  5. A Non-Linear Upscaling Approach for Wind Turbines Blades Based on Stresses

    NARCIS (Netherlands)

    Castillo Capponi, P.; Van Bussel, G.J.W.; Ashuri, T.; Kallesoe, B.

    2011-01-01

    The linear scaling laws for upscaling wind turbine blades show a linear increase of stresses due to the weight. However, the stresses should remain the same for a suitable design. Application of linear scaling laws may lead to an upscaled blade that may not be any more a feasible design. In this

  6. Measurement of lower limb alignment: there are within-person differences between weight-bearing and non-weight-bearing measurement modalities.

    Science.gov (United States)

    Schoenmakers, Daphne A L; Feczko, Peter Z; Boonen, Bert; Schotanus, Martijn G M; Kort, Nanne P; Emans, Pieter J

    2017-11-01

    Previous studies have compared weight-bearing mechanical leg axis (MLA) measurements to non-weight-bearing measurement modalities. Most of these studies compared mean or median values and did not analyse within-person differences between measurements. This study evaluates the within-person agreement of MLA measurements between weight-bearing full-length radiographs (FLR) and non-weight-bearing measurement modalities (computer-assisted surgery (CAS) navigation or MRI). Two independent observers measured the MLA on pre- and postoperative weight-bearing FLR in 168 patients. These measurements were compared to non-weight-bearing measurements obtained by CAS navigation or MRI. Absolute differences in individual subjects were calculated to determine the agreement between measurement modalities. Linear regression was used to evaluate the possibility that other independent variables impact the differences in measurements. A difference was found in preoperative measurements between FLR and CAS navigation (mean of 2.5° with limit of agreement (1.96 SD) of 6.4°), as well as between FLR and MRI measurements (mean of 2.4° with limit of agreement (1.96 SD) of 6.9°). Postoperatively, the mean difference between MLA measured on FLR compared to CAS navigation was 1.5° (limit of agreement (1.96 SD) of 4.6°). Linear regression analysis showed that weight-bearing MLA measurements vary significantly from non-weight-bearing MLA measurements. Differences were more severe in patients with mediolateral instability (p = 0.010), age (p = 0.049) and ≥3° varus or valgus alignment (p = 0.008). The clinical importance of this study lies in the finding that there are within-person differences between weight-bearing and non-weight-bearing measurement modalities. This has implications for preoperative planning, performing total knee arthroplasty (TKA), and clinical follow-up after TKA surgery using CAS navigation or patient-specific instrumentation. III.

  7. Habitat Preferences, Distribution Pattern, and Root Weight Estimation of Pasak Bumi (Eurycoma longifolia Jack.

    Directory of Open Access Journals (Sweden)

    Siti Masitoh Kartikawati

    2014-04-01

    Full Text Available Pasak bumi (Eurycoma longifolia Jack is one of non timber forest products with “indeterminate” conservation status and commercially traded in West Kalimantan. The research objective was to determine the potential of pasak bumi root per hectare and its ecological condition under natural habitat. Root weight of E. longifolia Jack was estimated using simple linear regression and exponential equation with stem diameter and height as independent variables. The results showed that the individual number of the population was 114 with the majority in seedling stage with 71 individuals (62.28%. The distribution was found in clumped pattern. Conditions of the habitat could be described as follows: daily average temperature of 25.6oC, daily average relative humidity of 73.6%, light intensity of 0.9 klx, and red-yellow podsolic soil with texture ranged from clay to sandy clay. The selected estimator model for E. longifolia Jack root weight used exponential equation with stem height as independent variable using the equation of Y= 21.99T0,010 and determination coefficient of 0.97. After height variable was added, the potential of E. longifolia Jack minimum root weight that could be harvested per hectare was 0.33 kg.Keywords: Eurycoma longifolia, habitat preference, distribution pattern, root weight

  8. The Schroedinger equation for central power law potentials and the classical theory of ordinary linear differential equations of the second order

    International Nuclear Information System (INIS)

    Lima, M.L.; Mignaco, J.A.

    1985-01-01

    It is shown that the rational power law potentials in the two-body radial Schoedinger equation admit a systematic treatment available from the classical theory of ordinary linear differential equations of the second order. The admissible potentials come into families evolved from equations having a fixed number of elementary singularities. As a consequence, relations are found and discussed among the several potentials in a family. (Author) [pt

  9. Bilinear nodal transport method in weighted diamond difference form

    International Nuclear Information System (INIS)

    Azmy, Y.Y.

    1987-01-01

    Nodal methods have been developed and implemented for the numerical solution of the discrete ordinates neutron transport equation. Numerical testing of these methods and comparison of their results to those obtained by conventional methods have established the high accuracy of nodal methods. Furthermore, it has been suggested that the linear-linear approximation is the most computationally efficient, practical nodal approximation. Indeed, this claim has been substantiated by comparing the accuracy in the solution, and the CPU time required to achieve convergence to that solution by several nodal approximations, as well as the diamond difference scheme. Two types of linear-linear nodal methods have been developed in the literature: analytic linear-linear (NLL) methods, in which the transverse-leakage terms are derived analytically, and approximate linear-linear (PLL) methods, in which these terms are approximated. In spite of their higher accuracy, NLL methods result in very complicated discrete-variable equations that exhibit a high degree of coupling, thus requiring special solution algorithms. On the other hand, the sacrificed accuracy in PLL methods is compensated for by the simple discrete-variable equations and diamond-difference-like solution algorithm. In this paper the authors outline the development of an NLL nodal method, the bilinear method, which can be written in a weighted diamond difference form with one spatial weight per dimension that is analytically derived rather than preassigned in an ad hoc fashion

  10. Spatial Analysis for Potential Water Catchment Areas using GIS: Weighted Overlay Technique

    Science.gov (United States)

    Awanda, Disyacitta; Anugrah Nurul, H.; Musfiroh, Zahrotul; Dinda Dwi, N. P.

    2017-12-01

    The development of applied GIS is growing rapidly and has been widely applied in various fields. Preparation of a model to obtain information is one of the benefits of GIS. Obtaining information for water resources such as water catchment areas is one part of GIS modelling. Water catchment model can be utilized to see the distribution of potential and ability of a region in water absorbing. The use of overlay techniques with the weighting obtained from the literature from previous research is used to build the model. Model builder parameters are obtained through remote sensing interpretation techniques such as land use, landforms, and soil texture. Secondary data such as rock type maps are also used as water catchment model parameters. The location of this research is in the upstream part of the Opak river basin. The purpose of this research is to get information about potential distribution of water catchment area with overlay technique. The results of this study indicate the potential of water catchment areas with excellent category, good, medium, poor and very poor. These results may indicate that the Upper river basin is either good or in bad condition, so it can be used for better water resources management policy determination.

  11. Design and performance testing of an ultrasonic linear motor with dual piezoelectric actuators.

    Science.gov (United States)

    Smithmaitrie, Pruittikorn; Suybangdum, Panumas; Laoratanakul, Pitak; Muensit, Nantakan

    2012-05-01

    In this work, design and performance testing of an ultrasonic linear motor with dual piezoelectric actuator patches are studied. The motor system consists of a linear stator, a pre-load weight, and two piezoelectric actuator patches. The piezoelectric actuators are bonded with the linear elastic stator at specific locations. The stator generates propagating waves when the piezoelectric actuators are subjected to harmonic excitations. Vibration characteristics of the linear stator are analyzed and compared with finite element and experimental results. The analytical, finite element, and experimental results show agreement. In the experiments, performance of the ultrasonic linear motor is tested. Relationships between velocity and pre-load weight, velocity and applied voltage, driving force and applied voltage, and velocity and driving force are reported. The design of the dual piezoelectric actuators yields a simpler structure with a smaller number of actuators and lower stator stiffness compared with a conventional design of an ultrasonic linear motor with fully laminated piezoelectric actuators.

  12. Weighted conditional least-squares estimation

    International Nuclear Information System (INIS)

    Booth, J.G.

    1987-01-01

    A two-stage estimation procedure is proposed that generalizes the concept of conditional least squares. The method is instead based upon the minimization of a weighted sum of squares, where the weights are inverses of estimated conditional variance terms. Some general conditions are given under which the estimators are consistent and jointly asymptotically normal. More specific details are given for ergodic Markov processes with stationary transition probabilities. A comparison is made with the ordinary conditional least-squares estimators for two simple branching processes with immigration. The relationship between weighted conditional least squares and other, more well-known, estimators is also investigated. In particular, it is shown that in many cases estimated generalized least-squares estimators can be obtained using the weighted conditional least-squares approach. Applications to stochastic compartmental models, and linear models with nested error structures are considered

  13. The Effect of Adherence to Dietary Tracking on Weight Loss: Using HLM to Model Weight Loss over Time.

    Science.gov (United States)

    Ingels, John Spencer; Misra, Ranjita; Stewart, Jonathan; Lucke-Wold, Brandon; Shawley-Brzoska, Samantha

    2017-01-01

    The role of dietary tracking on weight loss remains unexplored despite being part of multiple diabetes and weight management programs. Hence, participants of the Diabetes Prevention and Management (DPM) program (12 months, 22 sessions) tracked their food intake for the duration of the study. A scatterplot of days tracked versus total weight loss revealed a nonlinear relationship. Hence, the number of possible tracking days was divided to create the 3 groups of participants: rare trackers (66% total days tracked). After controlling for initial body mass index, hemoglobin A 1c , and gender, only consistent trackers had significant weight loss (-9.99 pounds), following a linear relationship with consistent loss throughout the year. In addition, the weight loss trend for the rare and inconsistent trackers followed a nonlinear path, with the holidays slowing weight loss and the onset of summer increasing weight loss. These results show the importance of frequent dietary tracking for consistent long-term weight loss success.

  14. Towards lexicographic multi-objective linear programming using grossone methodology

    Science.gov (United States)

    Cococcioni, Marco; Pappalardo, Massimo; Sergeyev, Yaroslav D.

    2016-10-01

    Lexicographic Multi-Objective Linear Programming (LMOLP) problems can be solved in two ways: preemptive and nonpreemptive. The preemptive approach requires the solution of a series of LP problems, with changing constraints (each time the next objective is added, a new constraint appears). The nonpreemptive approach is based on a scalarization of the multiple objectives into a single-objective linear function by a weighted combination of the given objectives. It requires the specification of a set of weights, which is not straightforward and can be time consuming. In this work we present both mathematical and software ingredients necessary to solve LMOLP problems using a recently introduced computational methodology (allowing one to work numerically with infinities and infinitesimals) based on the concept of grossone. The ultimate goal of such an attempt is an implementation of a simplex-like algorithm, able to solve the original LMOLP problem by solving only one single-objective problem and without the need to specify finite weights. The expected advantages are therefore obvious.

  15. The Schroedinger equation for central power law potentials and the classical theory of ordinary linear differential equations of the second order

    International Nuclear Information System (INIS)

    Lima, M.L.; Mignaco, J.A.

    1985-01-01

    It is shown that the rational power law potentials in the two-body radial Schrodinger equations admit a systematic treatment available from the classical theory of ordinary linear differential equations of the second order. The resulting potentials come into families evolved from equations having a fixed number of elementary regular singularities. As a consequence, relations are found and discussed among the several potentials in a family. (Author) [pt

  16. The physical imitation experiments of nuclear belt weight scaler

    International Nuclear Information System (INIS)

    Shi Qicun; Wang Mingqian; Sun Jinhua; Li Zhonghao

    1993-01-01

    The physical imitation experiments of the nuclear belt weight scaler (NBWS) were performed with a coal-loaded belt. The linearity, repetition and long-time stability; of the NBWS were measured. And the influence of pile shape, load bias and the composition of coal on weight calculation were studied

  17. Competitive inhibition can linearize dose-response and generate a linear rectifier.

    Science.gov (United States)

    Savir, Yonatan; Tu, Benjamin P; Springer, Michael

    2015-09-23

    Many biological responses require a dynamic range that is larger than standard bi-molecular interactions allow, yet the also ability to remain off at low input. Here we mathematically show that an enzyme reaction system involving a combination of competitive inhibition, conservation of the total level of substrate and inhibitor, and positive feedback can behave like a linear rectifier-that is, a network motif with an input-output relationship that is linearly sensitive to substrate above a threshold but unresponsive below the threshold. We propose that the evolutionarily conserved yeast SAGA histone acetylation complex may possess the proper physiological response characteristics and molecular interactions needed to perform as a linear rectifier, and we suggest potential experiments to test this hypothesis. One implication of this work is that linear responses and linear rectifiers might be easier to evolve or synthetically construct than is currently appreciated.

  18. The least weighted squares I. The asymptotic linearity of normal equations

    Czech Academy of Sciences Publication Activity Database

    Víšek, Jan Ámos

    2002-01-01

    Roč. 9, č. 15 (2002), s. 31-58 ISSN 1212-074X R&D Projects: GA AV ČR KSK1019101 Grant - others:GA UK(CZ) 255/2002/A EK /FSV Institutional research plan: CEZ:AV0Z1075907 Keywords : the least weighted squares * robust regression * asymptotic normality and representation Subject RIV: BA - General Mathematics

  19. Short-memory linear processes and econometric applications

    CERN Document Server

    Mynbaev, Kairat T

    2011-01-01

    This book serves as a comprehensive source of asymptotic results for econometric models with deterministic exogenous regressors. Such regressors include linear (more generally, piece-wise polynomial) trends, seasonally oscillating functions, and slowly varying functions including logarithmic trends, as well as some specifications of spatial matrices in the theory of spatial models. The book begins with central limit theorems (CLTs) for weighted sums of short memory linear processes. This part contains the analysis of certain operators in Lp spaces and their employment in the derivation of CLTs

  20. Influence of birth order, birth weight, colostrum and serum immunoglobulin G on neonatal piglet survival.

    Science.gov (United States)

    Cabrera, Rafael A; Lin, Xi; Campbell, Joy M; Moeser, Adam J; Odle, Jack

    2012-12-23

    Intake of colostrum after birth is essential to stimulate intestinal growth and function, and to provide systemic immunological protection via absorption of Immunoglobulin G (IgG). The birth order and weight of 745 piglets (from 75 litters) were recorded during a one-week period of farrowing. Only pigs weighing greater than 0.68 kg birth weight were chosen for the trial. Sow colostrum was collected during parturition, and piglets were bled between 48 and 72 hours post-birth. Piglet serum IgG and colostral IgG concentrations were determined by radial immunodiffusion. Sow parity had a significant (P birth order accounted for another 4% of the variation observed in piglet serum IgG concentration (P birth weight had no detectable effect. Piglet serum IgG concentration had both a linear (P Birth order had no detectable effect on survival, but birth weight had a positive linear effect (P birth had a 68% survival rate, and those weighing 1.6 kg (n = 158) had an 89% survival. We found that the combination of sow colostrum IgG concentration and birth order can account for 10% of the variation of piglet serum IgG concentration and that piglets with less than 1,000 mg/dl IgG serum concentration and weight of 0.9 kg at birth had low survival rate when compared to their larger siblings. The effective management of colostrum uptake in neonatal piglets in the first 24 hrs post-birth may potentially improve survival from birth to weaning.

  1. Linear relationships between cherry tomato traits

    Directory of Open Access Journals (Sweden)

    Bruno Giacomini Sari

    Full Text Available ABSTRACT: The objective of this study was to identify the linear relationship between cherry tomato yield components. Two uniformity trials, without treatments, were conducted on Lilli cherry tomato plants in a plastic greenhouse during the 2014 spring/summer season, with the plants in two stems. Variables observed for each plant were mean fruit length, mean fruit width, mean fruit weight, number of bunches, number of fruits per bunch, total number of fruits, and total fruit weight; a Pearson's correlation matrix was used to estimate the relationship between the variables. Path analysis was then performed considering total fruit weight as the main variable and the remaining variables as explanatory. Due to the severe multicollinearity, the variable 'number of fruits per bunch' was eliminated. Pearson's correlation coefficients were significant between explanatory and main variables. Mean fruit weight has a low cause-and-effect relationship with the total weight of fruits produced. A low cause-and-effect relationship was also observed between number of fruits and number of bunches. Cherry tomato productivity is directly related to the number of fruits per plant.

  2. Weight and height prediction of immobilized patients

    OpenAIRE

    Rabito,Estela Iraci; Vannucchi,Gabriela Bergamini; Suen,Vivian Marques Miguel; Castilho Neto,Laércio Lopes; Marchini,Júlio Sérgio

    2006-01-01

    OBJECTIVE: To confirm the adequacy of the formula suggested in the literature and/or to develop appropriate equations for the Brazilian population of immobilized patients based on simple anthropometric measurements. METHODS: Hospitalized patients were submitted to anthropometry and methods to estimate weight and height of bedridden patients were developed by multiple linear regression. RESULTS: Three hundred sixty eight persons were evaluated at two hospital centers and five weight-predicting...

  3. Learning Gene Regulatory Networks Computationally from Gene Expression Data Using Weighted Consensus

    KAUST Repository

    Fujii, Chisato

    2015-04-16

    Gene regulatory networks analyze the relationships between genes allowing us to un- derstand the gene regulatory interactions in systems biology. Gene expression data from the microarray experiments is used to obtain the gene regulatory networks. How- ever, the microarray data is discrete, noisy and non-linear which makes learning the networks a challenging problem and existing gene network inference methods do not give consistent results. Current state-of-the-art study uses the average-ranking-based consensus method to combine and average the ranked predictions from individual methods. However each individual method has an equal contribution to the consen- sus prediction. We have developed a linear programming-based consensus approach which uses learned weights from linear programming among individual methods such that the methods have di↵erent weights depending on their performance. Our result reveals that assigning di↵erent weights to individual methods rather than giving them equal weights improves the performance of the consensus. The linear programming- based consensus method is evaluated and it had the best performance on in silico and Saccharomyces cerevisiae networks, and the second best on the Escherichia coli network outperformed by Inferelator Pipeline method which gives inconsistent results across a wide range of microarray data sets.

  4. Linear codes associated to determinantal varieties

    DEFF Research Database (Denmark)

    Beelen, Peter; Ghorpade, Sudhir R.; Hasan, Sartaj Ul

    2015-01-01

    We consider a class of linear codes associated to projective algebraic varieties defined by the vanishing of minors of a fixed size of a generic matrix. It is seen that the resulting code has only a small number of distinct weights. The case of varieties defined by the vanishing of 2×2 minors is ...

  5. Solitary waves under the competition of linear and nonlinear periodic potentials

    International Nuclear Information System (INIS)

    Rapti, Z; Kevrekidis, P G; Konotop, V V; Jones, C K R T

    2007-01-01

    In this paper, we study the competition of the linear and nonlinear lattices and its effects on the stability and dynamics of bright solitary waves. We consider both lattices in a perturbative framework, whereby the technique of Hamiltonian perturbation theory can be used to obtain information about the existence of solutions, and the same approach, as well as eigenvalue count considerations, can be used to obtain detailed conditions about their linear stability. We find that the analytical results are in very good agreement with our numerical findings and can also be used to predict features of the dynamical evolution of such solutions. A particularly interesting result of these considerations is the existence of a tunable cancellation effect between the linear and nonlinear lattices that allows for increased mobility of the solitary wave

  6. Cord Blood Lysophosphatidylcholine 16: 1 is Positively Associated with Birth Weight

    Directory of Open Access Journals (Sweden)

    Yong-Ping Lu

    2018-01-01

    Full Text Available Background/Aims: Impaired birth outcomes, like low birth weight, have consistently been associated with increased disease susceptibility to hypertension in later life. Alterations in the maternal or fetal metabolism might impact on fetal growth and influence birth outcomes. Discerning associations between the maternal and fetal metabolome and surrogate parameters of fetal growth could give new insight into the complex relationship between intrauterine conditions, birth outcomes, and later life disease susceptibility. Methods: Using flow injection tandem mass spectrometry, targeted metabolomics was performed in serum samples obtained from 226 mother/child pairs at delivery. Associations between neonatal birth weight and concentrations of 163 maternal and fetal metabolites were analyzed. Results: After FDR adjustment using the Benjamini-Hochberg procedure lysophosphatidylcholines (LPC 14: 0, 16: 1, and 18: 1 were strongly positively correlated with birth weight. In a stepwise linear regression model corrected for established confounding factors of birth weight, LPC 16: 1 showed the strongest independent association with birth weight (CI: 93.63 - 168.94; P = 6.94×10-11 . The association with birth weight was stronger than classical confounding factors such as offspring sex (CI: -258.81- -61.32; P = 0.002 and maternal smoking during pregnancy (CI: -298.74 - -29.51; P = 0.017. Conclusions: After correction for multiple testing and adjustment for potential confounders, LPC 16: 1 showed a very strong and independent association with birth weight. The underlying molecular mechanisms linking fetal LPCs with birth weight need to be addressed in future studies.

  7. Variations on the planar Landau problem: canonical transformations, a purely linear potential and the half-plane

    International Nuclear Information System (INIS)

    Govaerts, Jan; Hounkonnou, M Norbert; Mweene, Habatwa V

    2009-01-01

    The ordinary Landau problem of a charged particle in a plane subjected to a perpendicular homogeneous and static magnetic field is reconsidered from different points of view. The role of phase space canonical transformations and their relation to a choice of gauge in the solution of the problem is addressed. The Landau problem is then extended to different contexts, in particular the singular situation of a purely linear potential term being added as an interaction, for which a complete purely algebraic solution is presented. This solution is then exploited to solve this same singular Landau problem in the half-plane, with as motivation the potential relevance of such a geometry for quantum Hall measurements in the presence of an electric field or a gravitational quantum well.

  8. Variations on the planar Landau problem: canonical transformations, a purely linear potential and the half-plane

    Energy Technology Data Exchange (ETDEWEB)

    Govaerts, Jan [Center for Particle Physics and Phenomenology (CP3), Institut de Physique Nucleaire, Universite catholique de Louvain (UCL), 2, Chemin du Cyclotron, B-1348 Louvain-la Neuve (Belgium); Hounkonnou, M Norbert [International Chair in Mathematical Physics and Applications (ICMPA-UNESCO Chair), University of Abomey-Calavi, 072 BP 50, Cotonou (Benin); Mweene, Habatwa V [Physics Department, University of Zambia, PO Box 32379, Lusaka (Zambia)], E-mail: Jan.Govaerts@uclouvain.be, E-mail: hounkonnou@yahoo.fr, E-mail: norbert.hounkonnou@cipma.uac.bj, E-mail: habatwamweene@yahoo.com, E-mail: hmweene@unza.zm

    2009-12-04

    The ordinary Landau problem of a charged particle in a plane subjected to a perpendicular homogeneous and static magnetic field is reconsidered from different points of view. The role of phase space canonical transformations and their relation to a choice of gauge in the solution of the problem is addressed. The Landau problem is then extended to different contexts, in particular the singular situation of a purely linear potential term being added as an interaction, for which a complete purely algebraic solution is presented. This solution is then exploited to solve this same singular Landau problem in the half-plane, with as motivation the potential relevance of such a geometry for quantum Hall measurements in the presence of an electric field or a gravitational quantum well.

  9. Frequency weighted model predictive control of wind turbine

    DEFF Research Database (Denmark)

    Klauco, Martin; Poulsen, Niels Kjølstad; Mirzaei, Mahmood

    2013-01-01

    This work is focused on applying frequency weighted model predictive control (FMPC) on three blade horizontal axis wind turbine (HAWT). A wind turbine is a very complex, non-linear system influenced by a stochastic wind speed variation. The reduced dynamics considered in this work are the rotatio...... predictive controller are presented. Statistical comparison between frequency weighted MPC, standard MPC and baseline PI controller is shown as well.......This work is focused on applying frequency weighted model predictive control (FMPC) on three blade horizontal axis wind turbine (HAWT). A wind turbine is a very complex, non-linear system influenced by a stochastic wind speed variation. The reduced dynamics considered in this work...... are the rotational degree of freedom of the rotor and the tower for-aft movement. The MPC design is based on a receding horizon policy and a linearised model of the wind turbine. Due to the change of dynamics according to wind speed, several linearisation points must be considered and the control design adjusted...

  10. Basicity of Systems of Sines with Linear Phase in Weighted Sobolev Spaces

    Directory of Open Access Journals (Sweden)

    V. F. Salmanov

    2013-01-01

    Full Text Available The perturbed systems of sines, which appear when solving some partial differential equations by the Fourier method, are considered in this paper. Basis properties of these systems in weighted Sobolev spaces of functions are studied.

  11. Eating out, weight and weight gain. A cross-sectional and prospective analysis in the context of the EPIC-PANACEA study.

    Science.gov (United States)

    Naska, A; Orfanos, P; Trichopoulou, A; May, A M; Overvad, K; Jakobsen, M U; Tjønneland, A; Halkjær, J; Fagherazzi, G; Clavel-Chapelon, F; Boutron-Ruault, M-C; Rohrmann, S; Hermann, S; Steffen, A; Haubrock, J; Oikonomou, E; Dilis, V; Katsoulis, M; Sacerdote, C; Sieri, S; Masala, G; Tumino, R; Mattiello, A; Bueno-de-Mesquita, H B; Skeie, G; Engeset, D; Barricarte, A; Rodríguez, L; Dorronsoro, M; Sánchez, M-J; Chirlaque, M-D; Agudo, A; Manjer, J; Wirfält, E; Hellström, V; Shungin, D; Khaw, K-T; Wareham, N J; Spencer, E A; Freisling, H; Slimani, N; Vergnaud, A-C; Mouw, T; Romaguera, D; Odysseos, A; Peeters, P H M

    2011-03-01

    The aim of this study was to examine the association of body mass index (BMI) and weight gain with eating at restaurants and similar establishments or eating at work among 10 European countries of the European Prospective Investigation into Cancer and Nutrition (EPIC) study. This study included a representative sample of 24,310 randomly selected EPIC participants. Single 24-h dietary recalls with information on the place of consumption were collected using standardized procedures between 1995 and 2000. Eating at restaurants was defined to include all eating and drinking occasions at restaurants, cafeterias, bars and fast food outlets. Eating at work included all eating and drinking occasions at the workplace. Associations between eating at restaurants or eating at work and BMI or annual weight changes were assessed using sex-specific linear mixed-effects models, controlling for potential confounders. In southern Europe energy intake at restaurants was higher than intake at work, whereas in northern Europe eating at work appeared to contribute more to the mean daily intake than eating at restaurants. Cross-sectionally, eating at restaurants was found to be positively associated with BMI only among men (β=+0.24, P=0.003). Essentially no association was found between BMI and eating at work among both genders. In a prospective analysis among men, eating at restaurants was found to be positively, albeit nonsignificantly, associated with weight gain (β=+0.05, P=0.368). No association was detected between energy intake at restaurants and weight changes, controlling for total energy intake. Among men, eating at restaurants and similar establishments was associated with higher BMI and possibly weight gain.

  12. A mechanical comparison of linear and double-looped hung supplemental heavy chain resistance to the back squat: a case study.

    Science.gov (United States)

    Neelly, Kurt R; Terry, Joseph G; Morris, Martin J

    2010-01-01

    A relatively new and scarcely researched technique to increase strength is the use of supplemental heavy chain resistance (SHCR) in conjunction with plate weights to provide variable resistance to free weight exercises. The purpose of this case study was to determine the actual resistance being provided by a double-looped versus a linear hung SHCR to the back squat exercise. The linear technique simply hangs the chain directly from the bar, whereas the double-looped technique uses a smaller chain to adjust the height of the looped chain. In both techniques, as the squat descends, chain weight is unloaded onto the floor, and as the squat ascends, chain weight is progressively loaded back as resistance. One experienced and trained male weight lifter (age = 33 yr; height = 1.83 m; weight = 111.4 kg) served as the subject. Plate weight was set at 84.1 kg, approximately 50% of the subject's 1 repetition maximum. The SHCR was affixed to load cells, sampling at a frequency of 500 Hz, which were affixed to the Olympic bar. Data were collected as the subject completed the back squat under the following conditions: double-looped 1 chain (9.6 kg), double-looped 2 chains (19.2 kg), linear 1 chain, and linear 2 chains. The double-looped SHCR resulted in a 78-89% unloading of the chain weight at the bottom of the squat, whereas the linear hanging SHCR resulted in only a 36-42% unloading. The double-looped technique provided nearly 2 times the variable resistance at the top of the squat compared with the linear hanging technique, showing that attention must be given to the technique used to hang SHCR.

  13. Weighted Branching Simulation Distance for Parametric Weighted Kripke Structures

    DEFF Research Database (Denmark)

    Foshammer, Louise; Larsen, Kim Guldstrand; Mariegaard, Anders

    2016-01-01

    This paper concerns branching simulation for weighted Kripke structures with parametric weights. Concretely, we consider a weighted extension of branching simulation where a single transitions can be matched by a sequence of transitions while preserving the branching behavior. We relax this notion...... to allow for a small degree of deviation in the matching of weights, inducing a directed distance on states. The distance between two states can be used directly to relate properties of the states within a sub-fragment of weighted CTL. The problem of relating systems thus changes to minimizing the distance...... which, in the general parametric case, corresponds to finding suitable parameter valuations such that one system can approximately simulate another. Although the distance considers a potentially infinite set of transition sequences we demonstrate that there exists an upper bound on the length...

  14. Transmission of linear regression patterns between time series: from relationship in time series to complex networks.

    Science.gov (United States)

    Gao, Xiangyun; An, Haizhong; Fang, Wei; Huang, Xuan; Li, Huajiao; Zhong, Weiqiong; Ding, Yinghui

    2014-07-01

    The linear regression parameters between two time series can be different under different lengths of observation period. If we study the whole period by the sliding window of a short period, the change of the linear regression parameters is a process of dynamic transmission over time. We tackle fundamental research that presents a simple and efficient computational scheme: a linear regression patterns transmission algorithm, which transforms linear regression patterns into directed and weighted networks. The linear regression patterns (nodes) are defined by the combination of intervals of the linear regression parameters and the results of the significance testing under different sizes of the sliding window. The transmissions between adjacent patterns are defined as edges, and the weights of the edges are the frequency of the transmissions. The major patterns, the distance, and the medium in the process of the transmission can be captured. The statistical results of weighted out-degree and betweenness centrality are mapped on timelines, which shows the features of the distribution of the results. Many measurements in different areas that involve two related time series variables could take advantage of this algorithm to characterize the dynamic relationships between the time series from a new perspective.

  15. A comparison between index of entropy and catastrophe theory methods for mapping groundwater potential in an arid region.

    Science.gov (United States)

    Al-Abadi, Alaa M; Shahid, Shamsuddin

    2015-09-01

    In this study, index of entropy and catastrophe theory methods were used for demarcating groundwater potential in an arid region using weighted linear combination techniques in geographical information system (GIS) environment. A case study from Badra area in the eastern part of central of Iraq was analyzed and discussed. Six factors believed to have influence on groundwater occurrence namely elevation, slope, aquifer transmissivity and storativity, soil, and distance to fault were prepared as raster thematic layers to facility integration into GIS environment. The factors were chosen based on the availability of data and local conditions of the study area. Both techniques were used for computing weights and assigning ranks vital for applying weighted linear combination approach. The results of application of both modes indicated that the most influential groundwater occurrence factors were slope and elevation. The other factors have relatively smaller values of weights implying that these factors have a minor role in groundwater occurrence conditions. The groundwater potential index (GPI) values for both models were classified using natural break classification scheme into five categories: very low, low, moderate, high, and very high. For validation of generated GPI, the relative operating characteristic (ROC) curves were used. According to the obtained area under the curve, the catastrophe model with 78 % prediction accuracy was found to perform better than entropy model with 77 % prediction accuracy. The overall results indicated that both models have good capability for predicting groundwater potential zones.

  16. An example in linear quadratic optimal control

    NARCIS (Netherlands)

    Weiss, George; Zwart, Heiko J.

    1998-01-01

    We construct a simple example of a quadratic optimal control problem for an infinite-dimensional linear system based on a shift semigroup. This system has an unbounded control operator. The cost is quadratic in the input and the state, and the weighting operators are bounded. Despite its extreme

  17. Weight loss, Mortality and associated potentially modifiable nutritional risk factors among nursing home residents

    DEFF Research Database (Denmark)

    Beck, Anne Marie

    2015-01-01

    Objectives The objective of this follow-up study is to assess the association between different potentially modifiable nutritional risk factors; weight loss after six and 12 months and mortality. Design and setting A one year follow-up project among Danish nursing home residents. Participants...... A total of 441 nursing home resident living in 11 nursing homes. Measurements Odds ratio was calculated and used to assess the strength of association between different potentially modifiable nutritional risk factors and nutritional status of the participants. The difference in mortality between those who...... at most meals, chewing and swallowing problems. The prevalence of eating dependency; leaves 25% or more of food uneaten at most meals; swallowing problems and enteral nutrition were higher among those who died than among survivors. Conclusion A high percentage of old nursing home residents suffer from...

  18. Linear methods in band theory

    DEFF Research Database (Denmark)

    Andersen, O. Krogh

    1975-01-01

    of Korringa-Kohn-Rostoker, linear-combination-of-atomic-orbitals, and cellular methods; the secular matrix is linear in energy, the overlap integrals factorize as potential parameters and structure constants, the latter are canonical in the sense that they neither depend on the energy nor the cell volume...

  19. Linearly and nonlinearly optimized weighted essentially non-oscillatory methods for compressible turbulence

    Science.gov (United States)

    Taylor, Ellen Meredith

    Weighted essentially non-oscillatory (WENO) methods have been developed to simultaneously provide robust shock-capturing in compressible fluid flow and avoid excessive damping of fine-scale flow features such as turbulence. This is accomplished by constructing multiple candidate numerical stencils that adaptively combine so as to provide high order of accuracy and high bandwidth-resolving efficiency in continuous flow regions while averting instability-provoking interpolation across discontinuities. Under certain conditions in compressible turbulence, however, numerical dissipation remains unacceptably high even after optimization of the linear optimal stencil combination that dominates in smooth regions. The remaining nonlinear error arises from two primary sources: (i) the smoothness measurement that governs the application of adaptation away from the optimal stencil and (ii) the numerical properties of individual candidate stencils that govern numerical accuracy when adaptation engages. In this work, both of these sources are investigated, and corrective modifications to the WENO methodology are proposed and evaluated. Excessive nonlinear error due to the first source is alleviated through two separately considered procedures appended to the standard smoothness measurement technique that are designated the "relative smoothness limiter" and the "relative total variation limiter." In theory, appropriate values of their associated parameters should be insensitive to flow configuration, thereby sidestepping the prospect of costly parameter tuning; and this expectation of broad effectiveness is assessed in direct numerical simulations (DNS) of one-dimensional inviscid test problems, three-dimensional compressible isotropic turbulence of varying Reynolds and turbulent Mach numbers, and shock/isotropic-turbulence interaction (SITI). In the process, tools for efficiently comparing WENO adaptation behavior in smooth versus shock-containing regions are developed. The

  20. Influence of time off feed on broiler viscera weight, diameter, and shear.

    Science.gov (United States)

    Buhr, R J; Northcutt, J K; Lyon, C E; Rowland, G N

    1998-05-01

    The influence of time off feed on broiler viscera weight, intestinal diameter, and shear was studied by subjecting market-age male broilers (42, 44, or 48 d) to incremental feed withdrawal periods (0, 6, 12, 18, or 24 h). Body weight was determined prior to feed withdrawal and at the time of processing. After slaughter, scalding, and defeathering, the abdominal cavity was opened. Diameter and shear of the proventriculus-ventriculus junction, jejunum, and ileum segments were measured, as were gallbladder length and width. Thoracic and abdominal viscera, liver, and ventriculus weights were determined, and liver surface color was measured. Percentage body weight loss increased with longer feed withdrawal periods, as viscera, liver, and ventriculus weights decreased. Gallbladder length increased with time off feed, whereas its width did not change. Diameter of the proventriculus-ventriculus junction, jejunum, and ileum decreased with longer feed withdrawal periods. Shear values for the proventriculus-ventriculus junction, jejunum, and ileum were not influenced by time off feed. Positive correlations (P 0.4) between viscera weight and intestinal diameter were detected. Correlations between all measured parameters and shear values were not significant. Liver color measurements indicated that longer feed withdrawal periods resulted in significant linear decreases in L* (lightness), +a* (redness), and +b* (yellowness). Longer feed withdrawal periods decreased viscera weight and intestinal diameter, which would lower the potential for cutting the intestine during automated evisceration. However, the resulting greater gallbladder length (5 mm) would increase the possibility of bile contamination during evisceration.

  1. On D-branes from gauged linear sigma models

    International Nuclear Information System (INIS)

    Govindarajan, S.; Jayaraman, T.; Sarkar, T.

    2001-01-01

    We study both A-type and B-type D-branes in the gauged linear sigma model by considering worldsheets with boundary. The boundary conditions on the matter and vector multiplet fields are first considered in the large-volume phase/non-linear sigma model limit of the corresponding Calabi-Yau manifold, where we find that we need to add a contact term on the boundary. These considerations enable to us to derive the boundary conditions in the full gauged linear sigma model, including the addition of the appropriate boundary contact terms, such that these boundary conditions have the correct non-linear sigma model limit. Most of the analysis is for the case of Calabi-Yau manifolds with one Kaehler modulus (including those corresponding to hypersurfaces in weighted projective space), though we comment on possible generalisations

  2. Excess body weight in children may increase the length of hospital stay

    Directory of Open Access Journals (Sweden)

    Maria Teresa Bechere Fernandes

    2015-02-01

    Full Text Available OBJECTIVES: To investigate the prevalence of excess body weight in the pediatric ward of University Hospital and to test both the association between initial nutritional diagnosis and the length of stay and the in-hospital variation in nutritional status. METHODS: Retrospective cohort study based on information entered in clinical records from University Hospital. The data were collected from a convenience sample of 91 cases among children aged one to 10 years admitted to the hospital in 2009. The data that characterize the sample are presented in a descriptive manner. Additionally, we performed a multivariate linear regression analysis adjusted for age and gender. RESULTS: Nutritional classification at baseline showed that 87.8% of the children had a normal weight and that 8.9% had excess weight. The linear regression models showed that the average weight loss z-score of the children with excess weight compared with the group with normal weight was −0.48 (p = 0.018 and that their length of stay was 2.37 days longer on average compared with that of the normal-weight group (p = 0.047. CONCLUSIONS: The length of stay and loss of weight at the hospital may be greater among children with excess weight than among children with normal weight.

  3. Time-Weighted Balanced Stochastic Model Reduction

    DEFF Research Database (Denmark)

    Tahavori, Maryamsadat; Shaker, Hamid Reza

    2011-01-01

    A new relative error model reduction technique for linear time invariant (LTI) systems is proposed in this paper. Both continuous and discrete time systems can be reduced within this framework. The proposed model reduction method is mainly based upon time-weighted balanced truncation and a recently...

  4. ANALYSIS OF HOLLOW COIL HELICAL EXTENSION SPRING AND THE STUDY OF OPTIMIZING THE WEIGHT

    OpenAIRE

    Naman Gupta*1, Manas purohit2 & Deepika potghan3

    2017-01-01

    This paper shows the study which deals with the weight reduction for tensile extension spring by changing the solid spring to hollow one. The springs which are generally used are in solid form due to which the weight of entire body in which the spring is attached gets increased. The forces which can be act on spring may be linear push or linear pull or radial type. This spring deflect by pulling and regain its shape when pulling is neglect. The weight of tensile spring is reduced by changing ...

  5. Orally disintegrating olanzapine and potential differences in treatment-emergent weight gain

    NARCIS (Netherlands)

    Karagianis, Jamie; Hoffmann, Vicki Poole; Arranz, Belen; Treuer, Tamás; Maguire, Gerald A.; de Haan, Lieuwe; Chawla, Bharat

    2008-01-01

    Several papers and communications have reported possible weight reduction or less weight gain when patients start or switch to orally disintegrating olanzapine, as contrasted with standard oral olanzapine tablets. In this paper, the current literature is reviewed and hypothesized mechanisms of

  6. Assessing the potential effectiveness of food and beverage taxes and subsidies for improving public health: a systematic review of prices, demand and body weight outcomes.

    Science.gov (United States)

    Powell, L M; Chriqui, J F; Khan, T; Wada, R; Chaloupka, F J

    2013-02-01

    Taxes and subsidies are increasingly being considered as potential policy instruments to incentivize consumers to improve their food and beverage consumption patterns and related health outcomes. This study provided a systematic review of recent U.S. studies on the price elasticity of demand for sugar-sweetened beverages (SSBs), fast food, and fruits and vegetables, as well as the direct associations of prices/taxes with body weight outcomes. Based on the recent literature, the price elasticity of demand for SSBs, fast food, fruits and vegetables was estimated to be -1.21, -0.52, -0.49 and -0.48, respectively. The studies that linked soda taxes to weight outcomes showed minimal impacts on weight; however, they were based on existing state-level sales taxes that were relatively low. Higher fast-food prices were associated with lower weight outcomes particularly among adolescents, suggesting that raising prices would potentially impact weight outcomes. Lower fruit and vegetable prices were generally found to be associated with lower body weight outcomes among both low-income children and adults, suggesting that subsidies that would reduce the cost of fruits and vegetables for lower-socioeconomic populations may be effective in reducing obesity. Pricing instruments should continue to be considered and evaluated as potential policy instruments to address public health risks. © 2012 The Authors. obesity reviews © 2012 International Association for the Study of Obesity.

  7. Assessing the Potential Effectiveness of Food and Beverage Taxes and Subsidies for Improving Public Health: A Systematic Review of Prices, Demand and Body Weight Outcomes

    Science.gov (United States)

    Powell, Lisa M.; Chriqui, Jamie F.; Khan, Tamkeen; Wada, Roy; Chaloupka, Frank J.

    2012-01-01

    Taxes and subsidies are increasingly being considered as potential policy instruments to incentivize consumers to improve their food and beverage consumption patterns and related health outcomes. This study provided a systematic review of recent U.S. studies on the price elasticity of demand for sugar-sweetened beverages (SSBs), fast food and fruits and vegetables as well as the direct associations of prices/taxes with body weight outcomes. Based on the recent literature, the price elasticity of demand for SSBs, fast food, fruits and vegetables was estimated to be −1.21, −0.52, −0.49 and −0.48, respectively. The studies that linked soda taxes to weight outcomes showed minimal impacts on weight; however, they were based on existing state-level sales taxes that were relatively low. Higher fast-food prices were associated with lower weight outcomes particularly among adolescents suggesting that raising prices would potentially impact weight outcomes. Lower fruit and vegetable prices were generally found to be associated with lower body weight outcomes among both low-income children and adults suggesting that subsidies that would reduce the cost of fruits and vegetables for lower-socioeconomic populations may be effective in reducing obesity. Pricing instruments should continue to be considered and evaluated as potential policy instruments to address public health risks. PMID:23174017

  8. wACSF—Weighted atom-centered symmetry functions as descriptors in machine learning potentials

    Science.gov (United States)

    Gastegger, M.; Schwiedrzik, L.; Bittermann, M.; Berzsenyi, F.; Marquetand, P.

    2018-06-01

    We introduce weighted atom-centered symmetry functions (wACSFs) as descriptors of a chemical system's geometry for use in the prediction of chemical properties such as enthalpies or potential energies via machine learning. The wACSFs are based on conventional atom-centered symmetry functions (ACSFs) but overcome the undesirable scaling of the latter with an increasing number of different elements in a chemical system. The performance of these two descriptors is compared using them as inputs in high-dimensional neural network potentials (HDNNPs), employing the molecular structures and associated enthalpies of the 133 855 molecules containing up to five different elements reported in the QM9 database as reference data. A substantially smaller number of wACSFs than ACSFs is needed to obtain a comparable spatial resolution of the molecular structures. At the same time, this smaller set of wACSFs leads to a significantly better generalization performance in the machine learning potential than the large set of conventional ACSFs. Furthermore, we show that the intrinsic parameters of the descriptors can in principle be optimized with a genetic algorithm in a highly automated manner. For the wACSFs employed here, we find however that using a simple empirical parametrization scheme is sufficient in order to obtain HDNNPs with high accuracy.

  9. Novel point estimation from a semiparametric ratio estimator (SPRE): long-term health outcomes from short-term linear data, with application to weight loss in obesity.

    Science.gov (United States)

    Weissman-Miller, Deborah

    2013-11-02

    Point estimation is particularly important in predicting weight loss in individuals or small groups. In this analysis, a new health response function is based on a model of human response over time to estimate long-term health outcomes from a change point in short-term linear regression. This important estimation capability is addressed for small groups and single-subject designs in pilot studies for clinical trials, medical and therapeutic clinical practice. These estimations are based on a change point given by parameters derived from short-term participant data in ordinary least squares (OLS) regression. The development of the change point in initial OLS data and the point estimations are given in a new semiparametric ratio estimator (SPRE) model. The new response function is taken as a ratio of two-parameter Weibull distributions times a prior outcome value that steps estimated outcomes forward in time, where the shape and scale parameters are estimated at the change point. The Weibull distributions used in this ratio are derived from a Kelvin model in mechanics taken here to represent human beings. A distinct feature of the SPRE model in this article is that initial treatment response for a small group or a single subject is reflected in long-term response to treatment. This model is applied to weight loss in obesity in a secondary analysis of data from a classic weight loss study, which has been selected due to the dramatic increase in obesity in the United States over the past 20 years. A very small relative error of estimated to test data is shown for obesity treatment with the weight loss medication phentermine or placebo for the test dataset. An application of SPRE in clinical medicine or occupational therapy is to estimate long-term weight loss for a single subject or a small group near the beginning of treatment.

  10. Combining forecast weights: Why and how?

    Science.gov (United States)

    Yin, Yip Chee; Kok-Haur, Ng; Hock-Eam, Lim

    2012-09-01

    This paper proposes a procedure called forecast weight averaging which is a specific combination of forecast weights obtained from different methods of constructing forecast weights for the purpose of improving the accuracy of pseudo out of sample forecasting. It is found that under certain specified conditions, forecast weight averaging can lower the mean squared forecast error obtained from model averaging. In addition, we show that in a linear and homoskedastic environment, this superior predictive ability of forecast weight averaging holds true irrespective whether the coefficients are tested by t statistic or z statistic provided the significant level is within the 10% range. By theoretical proofs and simulation study, we have shown that model averaging like, variance model averaging, simple model averaging and standard error model averaging, each produces mean squared forecast error larger than that of forecast weight averaging. Finally, this result also holds true marginally when applied to business and economic empirical data sets, Gross Domestic Product (GDP growth rate), Consumer Price Index (CPI) and Average Lending Rate (ALR) of Malaysia.

  11. Decoding suprathreshold stochastic resonance with optimal weights

    International Nuclear Information System (INIS)

    Xu, Liyan; Vladusich, Tony; Duan, Fabing; Gunn, Lachlan J.; Abbott, Derek; McDonnell, Mark D.

    2015-01-01

    We investigate an array of stochastic quantizers for converting an analog input signal into a discrete output in the context of suprathreshold stochastic resonance. A new optimal weighted decoding is considered for different threshold level distributions. We show that for particular noise levels and choices of the threshold levels optimally weighting the quantizer responses provides a reduced mean square error in comparison with the original unweighted array. However, there are also many parameter regions where the original array provides near optimal performance, and when this occurs, it offers a much simpler approach than optimally weighting each quantizer's response. - Highlights: • A weighted summing array of independently noisy binary comparators is investigated. • We present an optimal linearly weighted decoding scheme for combining the comparator responses. • We solve for the optimal weights by applying least squares regression to simulated data. • We find that the MSE distortion of weighting before summation is superior to unweighted summation of comparator responses. • For some parameter regions, the decrease in MSE distortion due to weighting is negligible

  12. Linear and nonlinear intersubband optical absorption in a disk-shaped quantum dot with a parabolic potential plus an inverse squared potential in a static magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Liu Guanghui [Department of Physics, College of Physics and Electronic Engineering, Guangzhou University, Guangzhou 510006 (China); Guo Kangxian, E-mail: axguo@sohu.com [Department of Physics, College of Physics and Electronic Engineering, Guangzhou University, Guangzhou 510006 (China); Wang Chao [Institute of Public Administration, Guangzhou University, Guangzhou 510006 (China)

    2012-06-15

    The linear and nonlinear optical absorption in a disk-shaped quantum dot (DSQD) with parabolic potential plus an inverse squared potential in the presence of a static magnetic field are theoretically investigated within the framework of the compact-density-matrix approach and iterative method. The energy levels and the wave functions of an electron in the DSQD are obtained by using the effective mass approximation. Numerical calculations are presented for typical GaAs/AlAs DSQD. It is found that the optical absorption coefficients are strongly affected not only by a static magnetic field, but also by the strength of external field, the confinement frequency and the incident optical intensity.

  13. Linear and nonlinear intersubband optical absorption in a disk-shaped quantum dot with a parabolic potential plus an inverse squared potential in a static magnetic field

    International Nuclear Information System (INIS)

    Liu Guanghui; Guo Kangxian; Wang Chao

    2012-01-01

    The linear and nonlinear optical absorption in a disk-shaped quantum dot (DSQD) with parabolic potential plus an inverse squared potential in the presence of a static magnetic field are theoretically investigated within the framework of the compact-density-matrix approach and iterative method. The energy levels and the wave functions of an electron in the DSQD are obtained by using the effective mass approximation. Numerical calculations are presented for typical GaAs/AlAs DSQD. It is found that the optical absorption coefficients are strongly affected not only by a static magnetic field, but also by the strength of external field, the confinement frequency and the incident optical intensity.

  14. Do the Five A’s Work When Physicians Counsel About Weight Loss?

    Science.gov (United States)

    Alexander, Stewart C.; Cox, Mary E.; Boling Turer, Christy L.; Lyna, Pauline; Østbye, Truls; Tulsky, James A.; Dolor, Rowena J.; Pollak, Kathryn I.

    2012-01-01

    BACKGROUND AND OBJECTIVES More than two thirds of Americans are overweight or obese. Physician counseling may help patients lose weight; however, physicians perceive these discussions as somewhat futile and time-consuming. An effective and efficient tool for smoking cessation is the Five A’s (Ask, Advise, Assess, Assist, and Arrange). We studied the effectiveness of the Five A’s in weight-loss counseling. METHODS We audiorecorded primary care encounters between 40 physicians and 461 of their overweight or obese patients. All were told the study was about preventive health, not weight specifically. Encounters were coded for physician use of the Five A’s. Patients’ motivation and confidence were assessed before and immediately after the encounter. Three months later, we assessed patient change in dietary fat intake, exercise, and weight. RESULTS Generalized linear models were fit adjusting for patient clustering within physician. Physicians used at least one of the Five A’s often (83%). Physicians routinely Ask and Advise patients to lose weight; however, they rarely Assess, Assist, or Arrange. Assist and Arrange were related to diet improvement, whereas Advise was associated with increases in motivation and confidence to change dietary fat intake and confidence to lose weight. CONCLUSIONS Similar to smoking cessation counseling, physicians routinely Asked and Advised patients to lose weight; however, they rarely Assessed, Assisted, or Arranged. Given the potential impact of using all of these counseling tools on changing patient behavior, physicians should be encouraged to increase their use of the Five A’s when counseling patients to lose weight. PMID:21380950

  15. Theoretical studies of MHD plasma molecules. I. Potential energy curves and dipole moments of linear KOH

    International Nuclear Information System (INIS)

    England, W.B.

    1978-01-01

    Uncorrelated and correlated potential energy curves and dipole moments are reported for linear KOH. The compound is found to be ionic, K + OH - . Minimum energy bond lengths are R/sub KO/=4.2913 au and R/sub OH/=1.7688 au, with an estimated accuracy of 2%. The corresponding dipole moment is 3.3 au (8.46 D) with a similar accuracy estimate. This is to our knowledge the first value ever reported for the KOH dipole moment, and the large value suggests that KOH will be an effective electron scatterer in MHD plasmas

  16. Use of linear discriminant function analysis in seed morphotype ...

    African Journals Online (AJOL)

    Use of linear discriminant function analysis in seed morphotype relationship study in 31 ... Data were collected on 100-seed weight, seed length and seed width. ... to the Mesoamerican gene pool, comprising the cultigroups Sieva-Big Lima, ...

  17. Linear Unlearning for Cross-Validation

    DEFF Research Database (Denmark)

    Hansen, Lars Kai; Larsen, Jan

    1996-01-01

    The leave-one-out cross-validation scheme for generalization assessment of neural network models is computationally expensive due to replicated training sessions. In this paper we suggest linear unlearning of examples as an approach to approximative cross-validation. Further, we discuss...... time series prediction benchmark demonstrate the potential of the linear unlearning technique...

  18. Noise and non-linearities in high-throughput data

    International Nuclear Information System (INIS)

    Nguyen, Viet-Anh; Lió, Pietro; Koukolíková-Nicola, Zdena; Bagnoli, Franco

    2009-01-01

    High-throughput data analyses are becoming common in biology, communications, economics and sociology. The vast amounts of data are usually represented in the form of matrices and can be considered as knowledge networks. Spectra-based approaches have proved useful in extracting hidden information within such networks and for estimating missing data, but these methods are based essentially on linear assumptions. The physical models of matching, when applicable, often suggest non-linear mechanisms, that may sometimes be identified as noise. The use of non-linear models in data analysis, however, may require the introduction of many parameters, which lowers the statistical weight of the model. According to the quality of data, a simpler linear analysis may be more convenient than more complex approaches. In this paper, we show how a simple non-parametric Bayesian model may be used to explore the role of non-linearities and noise in synthetic and experimental data sets

  19. On the effects of a screw dislocation and a linear potential on the harmonic oscillator

    Energy Technology Data Exchange (ETDEWEB)

    Bueno, M.J.; Furtado, C., E-mail: furtado@fisica.ufpb.br; Bakke, K., E-mail: kbakke@fisica.ufpb.br

    2016-09-01

    Quantum effects on the harmonic oscillator due to the presence of a linear scalar potential and a screw dislocation are investigated. By searching for bound states solutions, it is shown that an Aharonov-Bohm-type effect for bound states and a restriction of the values of the angular frequency of the harmonic oscillator can be obtained, where the allowed values are determined by the topology of the screw dislocation and the quantum numbers associated with the radial modes and the angular momentum. As particular cases, the angular frequency and the energy levels associated with the ground state and the first excited state of the system are obtained.

  20. Describing Growth Pattern of Bali Cows Using Non-linear Regression Models

    Directory of Open Access Journals (Sweden)

    Mohd. Hafiz A.W

    2016-12-01

    Full Text Available The objective of this study was to evaluate the best fit non-linear regression model to describe the growth pattern of Bali cows. Estimates of asymptotic mature weight, rate of maturing and constant of integration were derived from Brody, von Bertalanffy, Gompertz and Logistic models which were fitted to cross-sectional data of body weight taken from 74 Bali cows raised in MARDI Research Station Muadzam Shah Pahang. Coefficient of determination (R2 and residual mean squares (MSE were used to determine the best fit model in describing the growth pattern of Bali cows. Von Bertalanffy model was the best model among the four growth functions evaluated to determine the mature weight of Bali cattle as shown by the highest R2 and lowest MSE values (0.973 and 601.9, respectively, followed by Gompertz (0.972 and 621.2, respectively, Logistic (0.971 and 648.4, respectively and Brody (0.932 and 660.5, respectively models. The correlation between rate of maturing and mature weight was found to be negative in the range of -0.170 to -0.929 for all models, indicating that animals of heavier mature weight had lower rate of maturing. The use of non-linear model could summarize the weight-age relationship into several biologically interpreted parameters compared to the entire lifespan weight-age data points that are difficult and time consuming to interpret.

  1. A phenomenological biological dose model for proton therapy based on linear energy transfer spectra.

    Science.gov (United States)

    Rørvik, Eivind; Thörnqvist, Sara; Stokkevåg, Camilla H; Dahle, Tordis J; Fjaera, Lars Fredrik; Ytre-Hauge, Kristian S

    2017-06-01

    The relative biological effectiveness (RBE) of protons varies with the radiation quality, quantified by the linear energy transfer (LET). Most phenomenological models employ a linear dependency of the dose-averaged LET (LET d ) to calculate the biological dose. However, several experiments have indicated a possible non-linear trend. Our aim was to investigate if biological dose models including non-linear LET dependencies should be considered, by introducing a LET spectrum based dose model. The RBE-LET relationship was investigated by fitting of polynomials from 1st to 5th degree to a database of 85 data points from aerobic in vitro experiments. We included both unweighted and weighted regression, the latter taking into account experimental uncertainties. Statistical testing was performed to decide whether higher degree polynomials provided better fits to the data as compared to lower degrees. The newly developed models were compared to three published LET d based models for a simulated spread out Bragg peak (SOBP) scenario. The statistical analysis of the weighted regression analysis favored a non-linear RBE-LET relationship, with the quartic polynomial found to best represent the experimental data (P = 0.010). The results of the unweighted regression analysis were on the borderline of statistical significance for non-linear functions (P = 0.053), and with the current database a linear dependency could not be rejected. For the SOBP scenario, the weighted non-linear model estimated a similar mean RBE value (1.14) compared to the three established models (1.13-1.17). The unweighted model calculated a considerably higher RBE value (1.22). The analysis indicated that non-linear models could give a better representation of the RBE-LET relationship. However, this is not decisive, as inclusion of the experimental uncertainties in the regression analysis had a significant impact on the determination and ranking of the models. As differences between the models were

  2. Tried and True: Springing into Linear Models

    Science.gov (United States)

    Darling, Gerald

    2012-01-01

    In eighth grade, students usually learn about forces in science class and linear relationships in math class, crucial topics that form the foundation for further study in science and engineering. An activity that links these two fundamental concepts involves measuring the distance a spring stretches as a function of how much weight is suspended…

  3. Activity related energy expenditure, appetite and energy intake: potential implications for weight management.

    Science.gov (United States)

    Harrington, D M; Martin, C K; Ravussin, E; Katzmarzyk, P T

    2013-08-01

    The aim was to investigate relationships between activity related energy expenditure (AREE), appetite ratings and energy intake (EI) in a sample of 40 male (26.4years; BMI 23.5kg/m(2)) and 42 female (26.9years; BMI 22.4kg/m(2)) participants. AREE was expressed as the residual value of the regression between total daily EE (by doubly labeled water) and resting EE (by indirect calorimetry). EI was measured using an ad libitum buffet meal and visual analogue scales measured subjective appetite ratings before and after the meal. AREE was divided into low, middle and high sex-specific tertiles. General linear models were used to investigate differences in appetite ratings and EI across AREE tertiles. Before the meal, males in the high AREE tertile had significantly lower desire to eat and lower prospective food consumption and higher feelings of fullness compared to those in the low tertile. Males in the middle tertile had significantly higher satiety quotients after the meal and lower EI compared to the other tertiles. No significant differences across tertiles were found in females. Sex differences in relationships between AREE, appetite ratings and EI may lead to differing patterns of EI and subsequent weight maintenance. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Height and Weight Estimation From Anthropometric Measurements Using Machine Learning Regressions.

    Science.gov (United States)

    Rativa, Diego; Fernandes, Bruno J T; Roque, Alexandre

    2018-01-01

    Height and weight are measurements explored to tracking nutritional diseases, energy expenditure, clinical conditions, drug dosages, and infusion rates. Many patients are not ambulant or may be unable to communicate, and a sequence of these factors may not allow accurate estimation or measurements; in those cases, it can be estimated approximately by anthropometric means. Different groups have proposed different linear or non-linear equations which coefficients are obtained by using single or multiple linear regressions. In this paper, we present a complete study of the application of different learning models to estimate height and weight from anthropometric measurements: support vector regression, Gaussian process, and artificial neural networks. The predicted values are significantly more accurate than that obtained with conventional linear regressions. In all the cases, the predictions are non-sensitive to ethnicity, and to gender, if more than two anthropometric parameters are analyzed. The learning model analysis creates new opportunities for anthropometric applications in industry, textile technology, security, and health care.

  5. Sports and leisure-time physical activity in pregnancy and birth weight: a population-based study.

    Science.gov (United States)

    Hegaard, H K; Petersson, K; Hedegaard, M; Ottesen, B; Dykes, A K; Henriksen, T B; Damm, P

    2010-02-01

    We examined the association between sports and other leisure-time physical activities during pregnancy and birth weight of babies born after 37 completed weeks of gestation. All Danish-speaking pregnant women attending routine antenatal care at the Department of Obstetrics, Aarhus University Hospital, Denmark, from August 1989 to September 1991 were invited to participate in the study. A total of 4458 healthy women who delivered after 37 completed gestational weeks participated in this study. The associations between sports (0, 1-2, 3+ h/week) or leisure-time physical activity (sedentary, light, and moderate to heavy) and birth weight were examined by linear and logistic regression and adjusted for potential confounding factors such as smoking, parity, schooling, pre-pregnancy body mass index and gestational age. The results showed that pregnant women who practiced sports or were moderate to heavy leisure-time physical active during the early second or the early third trimester gave birth to infants with a similar birth weight as inactive women. The proportion of newborns with a low (/=4500 g) was also unchanged. In conclusion, in this large population-based study, we found no association between sports and leisure-time physical activity and low-birth weight, high-birth weight, or average-birth weight.

  6. Gestational weight gain.

    Science.gov (United States)

    Kominiarek, Michelle A; Peaceman, Alan M

    2017-12-01

    Prenatal care providers are advised to evaluate maternal weight at each regularly scheduled prenatal visit, monitor progress toward meeting weight gain goals, and provide individualized counseling if significant deviations from a woman's goals occur. Today, nearly 50% of women exceed their weight gain goals with overweight and obese women having the highest prevalence of excessive weight gain. Risks of inadequate weight gain include low birthweight and failure to initiate breast-feeding whereas the risks of excessive weight gain include cesarean deliveries and postpartum weight retention for the mother and large-for-gestational-age infants, macrosomia, and childhood overweight or obesity for the offspring. Prenatal care providers have many resources and tools to incorporate weight and other health behavior counseling into routine prenatal practices. Because many women are motivated to improve health behaviors, pregnancy is often considered the optimal time to intervene for issues related to eating habits and physical activity to prevent excessive weight gain. Gestational weight gain is a potentially modifiable risk factor for a number of adverse maternal and neonatal outcomes and meta-analyses of randomized controlled trials report that diet or exercise interventions during pregnancy can help reduce excessive weight gain. However, health behavior interventions for gestational weight gain have not significantly improved other maternal and neonatal outcomes and have limited effectiveness in overweight and obese women. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Parental obesity moderates the relationship between childhood appetitive traits and weight.

    Science.gov (United States)

    Fuemmeler, Bernard F; Lovelady, Cheryl A; Zucker, Nancy L; Østbye, Truls

    2013-04-01

    In this study, the independent and combined associations between childhood appetitive traits and parental obesity on weight gain from 0 to 24 months and body mass index (BMI) z-score at 24 months in a diverse community-based sample of dual parent families (n = 213) were examined. Participants were mothers who had recently completed a randomized trial of weight loss for overweight/obese postpartum women. As measures of childhood appetitive traits, mothers completed subscales of the Children's Eating Behavior Questionnaire, including Desire to Drink (DD), Enjoyment of Food (EF), and Satiety Responsiveness (SR), and a 24-h dietary recall for their child. Heights and weights were measured for all children and mothers and self-reported for mothers' partners. The relationship between children's appetitive traits and parental obesity on toddler weight gain and BMI z-score were evaluated using multivariate linear regression models, controlling for a number of potential confounders. Having two obese parents was related to greater weight gain from birth to 24 months independent of childhood appetitive traits, and although significant associations were found between appetitive traits (DD and SR) and child BMI z-score at 24 months, these associations were observed only among children who had two obese parents. When both parents were obese, increasing DD and decreasing SR were associated with a higher BMI z-score. The results highlight the importance of considering familial risk factors when examining the relationship between childhood appetitive traits on childhood obesity. Copyright © 2012 The Obesity Society.

  8. Spectral neighbor analysis method for automated generation of quantum-accurate interatomic potentials

    International Nuclear Information System (INIS)

    Thompson, A.P.; Swiler, L.P.; Trott, C.R.; Foiles, S.M.; Tucker, G.J.

    2015-01-01

    We present a new interatomic potential for solids and liquids called Spectral Neighbor Analysis Potential (SNAP). The SNAP potential has a very general form and uses machine-learning techniques to reproduce the energies, forces, and stress tensors of a large set of small configurations of atoms, which are obtained using high-accuracy quantum electronic structure (QM) calculations. The local environment of each atom is characterized by a set of bispectrum components of the local neighbor density projected onto a basis of hyperspherical harmonics in four dimensions. The bispectrum components are the same bond-orientational order parameters employed by the GAP potential [1]. The SNAP potential, unlike GAP, assumes a linear relationship between atom energy and bispectrum components. The linear SNAP coefficients are determined using weighted least-squares linear regression against the full QM training set. This allows the SNAP potential to be fit in a robust, automated manner to large QM data sets using many bispectrum components. The calculation of the bispectrum components and the SNAP potential are implemented in the LAMMPS parallel molecular dynamics code. We demonstrate that a previously unnoticed symmetry property can be exploited to reduce the computational cost of the force calculations by more than one order of magnitude. We present results for a SNAP potential for tantalum, showing that it accurately reproduces a range of commonly calculated properties of both the crystalline solid and the liquid phases. In addition, unlike simpler existing potentials, SNAP correctly predicts the energy barrier for screw dislocation migration in BCC tantalum

  9. Spectral neighbor analysis method for automated generation of quantum-accurate interatomic potentials

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Aidan P. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States). Multiscale Science Dept.; Swiler, Laura P. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States). Optimization and Uncertainty Quantification Dept.; Trott, Christian R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Scalable Algorithms Dept.; Foiles, Stephen M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Computational Materials and Data Science Dept.; Tucker, Garritt J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Computational Materials and Data Science Dept.; Drexel Univ., Philadelphia, PA (United States). Dept. of Materials Science and Engineering

    2015-03-15

    Here, we present a new interatomic potential for solids and liquids called Spectral Neighbor Analysis Potential (SNAP). The SNAP potential has a very general form and uses machine-learning techniques to reproduce the energies, forces, and stress tensors of a large set of small configurations of atoms, which are obtained using high-accuracy quantum electronic structure (QM) calculations. The local environment of each atom is characterized by a set of bispectrum components of the local neighbor density projected onto a basis of hyperspherical harmonics in four dimensions. The bispectrum components are the same bond-orientational order parameters employed by the GAP potential [1]. The SNAP potential, unlike GAP, assumes a linear relationship between atom energy and bispectrum components. The linear SNAP coefficients are determined using weighted least-squares linear regression against the full QM training set. This allows the SNAP potential to be fit in a robust, automated manner to large QM data sets using many bispectrum components. The calculation of the bispectrum components and the SNAP potential are implemented in the LAMMPS parallel molecular dynamics code. We demonstrate that a previously unnoticed symmetry property can be exploited to reduce the computational cost of the force calculations by more than one order of magnitude. We present results for a SNAP potential for tantalum, showing that it accurately reproduces a range of commonly calculated properties of both the crystalline solid and the liquid phases. In addition, unlike simpler existing potentials, SNAP correctly predicts the energy barrier for screw dislocation migration in BCC tantalum.

  10. Spectral neighbor analysis method for automated generation of quantum-accurate interatomic potentials

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, A.P., E-mail: athomps@sandia.gov [Multiscale Science Department, Sandia National Laboratories, PO Box 5800, MS 1322, Albuquerque, NM 87185 (United States); Swiler, L.P., E-mail: lpswile@sandia.gov [Optimization and Uncertainty Quantification Department, Sandia National Laboratories, PO Box 5800, MS 1318, Albuquerque, NM 87185 (United States); Trott, C.R., E-mail: crtrott@sandia.gov [Scalable Algorithms Department, Sandia National Laboratories, PO Box 5800, MS 1322, Albuquerque, NM 87185 (United States); Foiles, S.M., E-mail: foiles@sandia.gov [Computational Materials and Data Science Department, Sandia National Laboratories, PO Box 5800, MS 1411, Albuquerque, NM 87185 (United States); Tucker, G.J., E-mail: gtucker@coe.drexel.edu [Computational Materials and Data Science Department, Sandia National Laboratories, PO Box 5800, MS 1411, Albuquerque, NM 87185 (United States); Department of Materials Science and Engineering, Drexel University, Philadelphia, PA 19104 (United States)

    2015-03-15

    We present a new interatomic potential for solids and liquids called Spectral Neighbor Analysis Potential (SNAP). The SNAP potential has a very general form and uses machine-learning techniques to reproduce the energies, forces, and stress tensors of a large set of small configurations of atoms, which are obtained using high-accuracy quantum electronic structure (QM) calculations. The local environment of each atom is characterized by a set of bispectrum components of the local neighbor density projected onto a basis of hyperspherical harmonics in four dimensions. The bispectrum components are the same bond-orientational order parameters employed by the GAP potential [1]. The SNAP potential, unlike GAP, assumes a linear relationship between atom energy and bispectrum components. The linear SNAP coefficients are determined using weighted least-squares linear regression against the full QM training set. This allows the SNAP potential to be fit in a robust, automated manner to large QM data sets using many bispectrum components. The calculation of the bispectrum components and the SNAP potential are implemented in the LAMMPS parallel molecular dynamics code. We demonstrate that a previously unnoticed symmetry property can be exploited to reduce the computational cost of the force calculations by more than one order of magnitude. We present results for a SNAP potential for tantalum, showing that it accurately reproduces a range of commonly calculated properties of both the crystalline solid and the liquid phases. In addition, unlike simpler existing potentials, SNAP correctly predicts the energy barrier for screw dislocation migration in BCC tantalum.

  11. Factors Associated With Weight Change in Online Weight Management Communities: A Case Study in the LoseIt Reddit Community.

    Science.gov (United States)

    Pappa, Gisele Lobo; Cunha, Tiago Oliveira; Bicalho, Paulo Viana; Ribeiro, Antonio; Couto Silva, Ana Paula; Meira, Wagner; Beleigoli, Alline Maria Rezende

    2017-01-16

    Recent research has shown that of the 72% of American Internet users who have looked for health information online, 22% have searched for help to lose or control weight. This demand for information has given rise to many online weight management communities, where users support one another throughout their weight loss process. Whether and how user engagement in online communities relates to weight change is not totally understood. We investigated the activity behavior and analyze the semantic content of the messages of active users in LoseIt (r/loseit), a weight management community of the online social network Reddit. We then explored whether these features are associated with weight loss in this online social network. A data collection tool was used to collect English posts, comments, and other public metadata of active users (ie, users with at least one post or comment) on LoseIt from August 2010 to November 2014. Analyses of frequency and intensity of user interaction in the community were performed together with a semantic analysis of the messages, done by a latent Dirichlet allocation method. The association between weight loss and online user activity patterns, the semantics of the messages, and real-world variables was found by a linear regression model using 30-day weight change as the dependent variable. We collected posts and comments of 107,886 unique users. Among these, 101,003 (93.62%) wrote at least one comment and 38,981 (36.13%) wrote at least one post. Median percentage of days online was 3.81 (IQR 9.51). The 10 most-discussed semantic topics on posts were related to healthy food, clothing, calorie counting, workouts, looks, habits, support, and unhealthy food. In the subset of 754 users who had gender, age, and 30-day weight change data available, women were predominant and 92.9% (701/754) lost weight. Female gender, body mass index (BMI) at baseline, high levels of online activity, the number of upvotes received per post, and topics discussed

  12. Sports and leisure-time physical activity in pregnancy and birth weight: a population-based study

    DEFF Research Database (Denmark)

    Hegaard, H K; Petersson, K; Hedegaard, M

    2010-01-01

    We examined the association between sports and other leisure-time physical activities during pregnancy and birth weight of babies born after 37 completed weeks of gestation. All Danish-speaking pregnant women attending routine antenatal care at the Department of Obstetrics, Aarhus University......, light, and moderate to heavy) and birth weight were examined by linear and logistic regression and adjusted for potential confounding factors such as smoking, parity, schooling, pre-pregnancy body mass index and gestational age. The results showed that pregnant women who practiced sports or were...... Hospital, Denmark, from August 1989 to September 1991 were invited to participate in the study. A total of 4458 healthy women who delivered after 37 completed gestational weeks participated in this study. The associations between sports (0, 1-2, 3+ h/week) or leisure-time physical activity (sedentary...

  13. Maternal weight and excessive weight gain during pregnancy modify the immunomodulatory potential of breast milk.

    Science.gov (United States)

    Collado, Maria Carmen; Laitinen, Kirsi; Salminen, Seppo; Isolauri, Erika

    2012-07-01

    Breast milk is an optimal source of nutrition for infants. It contains bioactive components including bacteria that support the microbial colonization and immune system development of the infant. The determinants of human milk composition remain poorly understood, although maternal nutritional and immunological status as well as lifestyle and dietary habits seem to have an impact. The subjects selected were women from a prospective follow-up study categorized by BMI. Milk samples were taken after delivery and at 1 and 6 mo later for analysis of composition in regard to transforming growth factor (TGF)-β2, soluble CD14 (sCD14), cytokines, and microbiota. TGF-β2 and sCD14 levels in the breast milk of overweight mothers tended to be lower than the levels in that of normal-weight mothers. Also, higher levels of Staphylococcus group bacteria and lower levels of Bifidobacterium group bacteria were detected in overweight mothers as compared with normal-weight ones. The prevalence of Akkermansia muciniphila-type bacteria was also higher in overweight mothers, and the numbers of these bacteria were related to the interleukin (IL)-6 concentration in the colostrum, which was in turn related to lower counts of Bifidobacterium group bacteria in the breast milk of overweight women. Complex interactions of cytokines and microbiota in breast milk guide the microbiological, immunological, and metabolic programming of infant health. Our data may indicate the presence of an additional mechanism that may explain the heightened risk of obesity for infants of overweight and excessive weight gain mothers.

  14. The effect of monomer molecular weight on grafting reaction

    International Nuclear Information System (INIS)

    Wu Minghong; Ding Zhongli; Ma Zueteh

    1995-01-01

    In this paper, some condensed ethylene glycol acrylate monomers with different molecular weight being grafted to the PE film by means of pre-irradiation is reported. The effect of molecular weight of monomer on grafting reaction and the hydrophilicity of grafting sample have been discussed. The experimental results show: molar degrees of grafting decreased non-linearly with the increasement of molecular weight of monomer, the grafting reaction of polymer is greater effected by the swelling degree of PE film, the greater the swelling degree of grafting material, the higher the grating degree grafting is, the initial rate of grafting reaction decreased with the increasement of molecular weight of monomer. (author)

  15. Towards the International Linear Collider

    International Nuclear Information System (INIS)

    Lopez-Fernandez, Ricardo

    2006-01-01

    The broad physics potential of e+e- linear colliders was recognized by the high energy physics community right after the end of LEP in 2000. In 2007, the Large Hadron Collider (LHC) now under construction at CERN will obtain its first collisions. The LHC, colliding protons with protons at 14 TeV, will discover a standard model Higgs boson over the full potential mass range, and should be sensitive to new physics into the several TeV range. The program for the Linear Collider (LC) will be set in the context of the discoveries made at the LHC. All the proposals for a Linear Collider will extend the discoveries and provide a wealth of measurements that are essential for giving deeper understanding of their meaning, and pointing the way to further evolution of particle physics in the future. For the mexican groups is the right time to join such an effort

  16. Estimate the contribution of incubation parameters influence egg hatchability using multiple linear regression analysis.

    Science.gov (United States)

    Khalil, Mohamed H; Shebl, Mostafa K; Kosba, Mohamed A; El-Sabrout, Karim; Zaki, Nesma

    2016-08-01

    This research was conducted to determine the most affecting parameters on hatchability of indigenous and improved local chickens' eggs. Five parameters were studied (fertility, early and late embryonic mortalities, shape index, egg weight, and egg weight loss) on four strains, namely Fayoumi, Alexandria, Matrouh, and Montazah. Multiple linear regression was performed on the studied parameters to determine the most influencing one on hatchability. The results showed significant differences in commercial and scientific hatchability among strains. Alexandria strain has the highest significant commercial hatchability (80.70%). Regarding the studied strains, highly significant differences in hatching chick weight among strains were observed. Using multiple linear regression analysis, fertility made the greatest percent contribution (71.31%) to hatchability, and the lowest percent contributions were made by shape index and egg weight loss. A prediction of hatchability using multiple regression analysis could be a good tool to improve hatchability percentage in chickens.

  17. Associations of Maternal Weight Status Before, During, and After Pregnancy with Inflammatory Markers in Breast Milk.

    Science.gov (United States)

    Whitaker, Kara M; Marino, Regina C; Haapala, Jacob L; Foster, Laurie; Smith, Katy D; Teague, April M; Jacobs, David R; Fontaine, Patricia L; McGovern, Patricia M; Schoenfuss, Tonya C; Harnack, Lisa; Fields, David A; Demerath, Ellen W

    2017-12-01

    The goal of this study was to examine the associations of maternal weight status before, during, and after pregnancy with breast milk C-reactive protein (CRP) and interleukin 6 (IL-6), two bioactive markers of inflammation, measured at 1 and 3 months post partum. Participants were 134 exclusively breastfeeding mother-infant dyads taking part in the Mothers and Infants Linked for Health (MILK) study, who provided breast milk samples. Pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) were assessed by chart abstraction; postpartum weight loss was measured at the 1- and 3-month study visits. Linear regression was used to examine the associations of maternal weight status with repeated measures of breast milk CRP and IL-6 at 1 and 3 months, after adjustment for potential confounders. Pre-pregnancy BMI and excessive GWG, but not total GWG or postpartum weight loss, were independently associated with breast milk CRP after adjustment (β = 0.49, P milk CRP. The consequences of infants receiving varying concentrations of breast milk inflammatory markers are unknown; however, it is speculated that there are implications for the intergenerational transmission of disease risk. © 2017 The Obesity Society.

  18. Extending the precision and efficiency of the all-electron full-potential linearized augmented plane-wave density-functional theory method

    International Nuclear Information System (INIS)

    Michalicek, Gregor

    2015-01-01

    Density functional theory (DFT) is the most widely-used first-principles theory for analyzing, describing and predicting the properties of solids based on the fundamental laws of quantum mechanics. The success of the theory is a consequence of powerful approximations to the unknown exchange and correlation energy of the interacting electrons and of sophisticated electronic structure methods that enable the computation of the density functional equations on a computer. A widely used electronic structure method is the full-potential linearized augmented plane-wave (FLAPW) method, that is considered to be one of the most precise methods of its kind and often referred to as a standard. Challenged by the demand of treating chemically and structurally increasingly more complex solids, in this thesis this method is revisited and extended along two different directions: (i) precision and (ii) efficiency. In the full-potential linearized augmented plane-wave method the space of a solid is partitioned into nearly touching spheres, centered at each atom, and the remaining interstitial region between the spheres. The Kohn-Sham orbitals, which are used to construct the electron density, the essential quantity in DFT, are expanded into a linearized augmented plane-wave basis, which consists of plane waves in the interstitial region and angular momentum dependent radial functions in the spheres. In this thesis it is shown that for certain types of materials, e.g., materials with very broad electron bands or large band gaps, or materials that allow the usage of large space-filling spheres, the variational freedom of the basis in the spheres has to be extended in order to represent the Kohn-Sham orbitals with high precision over a large energy spread. Two kinds of additional radial functions confined to the spheres, so-called local orbitals, are evaluated and found to successfully eliminate this error. A new efficient basis set is developed, named linearized augmented lattice

  19. A pilot study examining diagnostic differences among exercise and weight suppression in bulimia nervosa and binge eating disorder.

    Science.gov (United States)

    Cook, Brian J; Steffen, Kristine J; Mitchell, James E; Otto, Maxwell; Crosby, Ross D; Cao, Li; Wonderlich, Stephen A; Crow, Scott; Hill, Laura; Le Grange, Daniel; Powers, Pauline

    2015-05-01

    The objective of this study was to investigate diagnostic differences in weight suppression (e.g., the difference between one's current body weight and highest non-pregnancy adult body weight) and exercise among Bulimia Nervosa (BN) and Binge Eating Disorder (BED). Because exercise may be a key contributor to weight suppression in BN, we were interested in examining the potential moderating effect of exercise on weight suppression in BN or BED. Participants with BN (n = 774) and BED (n = 285) completed self-report surveys of weight history, exercise and eating disorder symptoms. Generalised linear model analyses were used to examine the associations among diagnosis, exercise frequency and their interaction on weight suppression. Exercise frequency and BN/BED diagnosis were both associated with weight suppression. Additionally, exercise frequency moderated the relationship between diagnosis and weight suppression. Specifically, weight suppression was higher in BN than in BED among those with low exercise frequency but comparable in BN and BED among those with high exercise frequency. Our results suggest that exercise frequency may contribute to different weight suppression outcomes among BN and BED. This may inform clinical implications of exercise in these disorders. Specifically, much understanding of the differences among exercise frequency and the compensatory use of exercise in BN and BED is needed. Copyright © 2015 John Wiley & Sons, Ltd and Eating Disorders Association.

  20. Approximative analytic eigenvalues for orbital excitations in the case of a coulomb potential plus linear and quadratic radial terms

    International Nuclear Information System (INIS)

    Rekab, S.; Zenine, N.

    2006-01-01

    We consider the three dimensional non relativistic eigenvalue problem in the case of a Coulomb potential plus linear and quadratic radial terms. In the framework of the Rayleigh-Schrodinger Perturbation Theory, using a specific choice of the unperturbed Hamiltonian, we obtain approximate analytic expressions for the eigenvalues of orbital excitations. The implications and the range of validity of the obtained analytic expression are discussed

  1. Guidance for the utility of linear models in meta-analysis of genetic association studies of binary phenotypes.

    Science.gov (United States)

    Cook, James P; Mahajan, Anubha; Morris, Andrew P

    2017-02-01

    Linear mixed models are increasingly used for the analysis of genome-wide association studies (GWAS) of binary phenotypes because they can efficiently and robustly account for population stratification and relatedness through inclusion of random effects for a genetic relationship matrix. However, the utility of linear (mixed) models in the context of meta-analysis of GWAS of binary phenotypes has not been previously explored. In this investigation, we present simulations to compare the performance of linear and logistic regression models under alternative weighting schemes in a fixed-effects meta-analysis framework, considering designs that incorporate variable case-control imbalance, confounding factors and population stratification. Our results demonstrate that linear models can be used for meta-analysis of GWAS of binary phenotypes, without loss of power, even in the presence of extreme case-control imbalance, provided that one of the following schemes is used: (i) effective sample size weighting of Z-scores or (ii) inverse-variance weighting of allelic effect sizes after conversion onto the log-odds scale. Our conclusions thus provide essential recommendations for the development of robust protocols for meta-analysis of binary phenotypes with linear models.

  2. A double B1-mode 4-layer laminated piezoelectric linear motor.

    Science.gov (United States)

    Li, Xiaotian; Chen, Zhijiang; Dong, Shuxiang

    2012-12-01

    We report a miniature piezoelectric ultrasonic linear motor that is made of four Pb(Zr,Ti)O(3) (PZT) piezoelectric ceramic layers for low-voltage work. The 4-layer piezoelectric laminate works in two orthogonal first-bending modes for producing elliptical oscillations, which are then used to drive a contacting slider into continuous linear motion. Experimental results show that the miniature linear motor (size: 4 × 4 × 12 mm, weight: 1.7 g) can generate a large driving force of 0.48 N and a linear motion speed of up to 160 mm/s, using a 40 V(pp)/mm voltage drive at its resonance frequency of 64.5 kHz. The maximum efficiency of the linear motor is 30%.

  3. Performance Characteristics and Prediction of Bodyweight using Linear Body Measurements in Four Strains of Broiler Chicken

    OpenAIRE

    I. Udeh; J.O. Isikwenu and G. Ukughere

    2011-01-01

    The objectives of this study were to compare the performance characteristics of four strains of broiler chicken from 2 to 8 weeks of age and predict body weight of the broilers using linear body measurements. The four strains of broiler chicken used were Anak, Arbor Acre, Ross and Marshall. The parameters recorded were bodyweight, weight gain, total feed intake, feed conversion ratio, mortality and some linear body measurements (body length, body width, breast width, drumstick length, shank l...

  4. A symmetric Roos bound for linear codes

    NARCIS (Netherlands)

    Duursma, I.M.; Pellikaan, G.R.

    2006-01-01

    The van Lint–Wilson AB-method yields a short proof of the Roos bound for the minimum distance of a cyclic code. We use the AB-method to obtain a different bound for the weights of a linear code. In contrast to the Roos bound, the role of the codes A and B in our bound is symmetric. We use the bound

  5. Graphs and matroids weighted in a bounded incline algebra.

    Science.gov (United States)

    Lu, Ling-Xia; Zhang, Bei

    2014-01-01

    Firstly, for a graph weighted in a bounded incline algebra (or called a dioid), a longest path problem (LPP, for short) is presented, which can be considered the uniform approach to the famous shortest path problem, the widest path problem, and the most reliable path problem. The solutions for LPP and related algorithms are given. Secondly, for a matroid weighted in a linear matroid, the maximum independent set problem is studied.

  6. A smartphone-supported weight loss program: design of the ENGAGED randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Pellegrini Christine A

    2012-11-01

    Full Text Available Abstract Background Obesity remains a major public health challenge, demanding cost-effective and scalable weight management programs. Delivering key treatment components via mobile technology offers a potential way to reduce expensive in-person contact, thereby lowering the cost and burden of intensive weight loss programs. The ENGAGED study is a theory-guided, randomized controlled trial designed to examine the feasibility and efficacy of an abbreviated smartphone-supported weight loss program. Methods/design Ninety-six obese adults (BMI 30–39.9 kg/m2 will be randomized to one of three treatment conditions: (1 standard behavioral weight loss (STND, (2 technology-supported behavioral weight loss (TECH; or (3 self-guided behavioral weight loss (SELF. All groups will aim to achieve a 7% weight loss goal by reducing calorie and fat intake and progressively increasing moderate intensity physical activity to 175 minutes/week. STND and TECH will attend 8 group sessions and receive regular coaching calls during the first 6 months of the intervention; SELF will receive the Group Lifestyle Balance Program DVD’s and will not receive coaching calls. During months 1–6, TECH will use a specially designed smartphone application to monitor dietary intake, body weight, and objectively measured physical activity (obtained from a Blue-tooth enabled accelerometer. STND and SELF will self-monitor on paper diaries. Linear mixed modeling will be used to examine group differences on weight loss at months 3, 6, and 12. Self-monitoring adherence and diet and activity goal attainment will be tested as mediators. Discussion ENGAGED is an innovative weight loss intervention that integrates theory with emerging mobile technologies. We hypothesize that TECH, as compared to STND and SELF, will result in greater weight loss by virtue of improved behavioral adherence and goal achievement. Trial registration NCT01051713

  7. Disjoint hypercyclicity of weighted composition operators

    Indian Academy of Sciences (India)

    Hypercyclicity; supercyclicity; disjoint hypercyclicity; disjoint super- cyclicity; weighted composition operators; Hilbert space. 2010 Mathematics Subject Classification. 47A16, 47B33, 47B38. 1. Introduction. Let X be a topological vector space and T a bounded linear operator on X. The T-orbit of a vector x ∈ X is the set. O(x,T) ...

  8. Peak thrust operation of linear induction machines from parameter identification

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Z.; Eastham, T.R.; Dawson, G.E. [Queen`s Univ., Kingston, Ontario (Canada). Dept. of Electrical and Computer Engineering

    1995-12-31

    Various control strategies are being used to achieve high performance operation of linear drives. To maintain minimum volume and weight of the power supply unit on board the transportation vehicle, peak thrust per unit current operation is a desirable objective. True peak thrust per unit current through slip control is difficult to achieve because the parameters of linear induction machines vary during normal operation. This paper first develops a peak thrust per unit current control law based on the per-phase equivalent circuit for linear induction machines. The algorithm for identification of the variable parameters in induction machines is then presented. Application to an operational linear induction machine (LIM) demonstrates the utility of this algorithm. The control strategy is then simulated, based on an operational transit LIM, to show the capability of achieving true peak thrust operation for linear induction machines.

  9. Aortic and Hepatic Contrast Enhancement During Hepatic-Arterial and Portal Venous Phase Computed Tomography Scanning: Multivariate Linear Regression Analysis Using Age, Sex, Total Body Weight, Height, and Cardiac Output.

    Science.gov (United States)

    Masuda, Takanori; Nakaura, Takeshi; Funama, Yoshinori; Higaki, Toru; Kiguchi, Masao; Imada, Naoyuki; Sato, Tomoyasu; Awai, Kazuo

    We evaluated the effect of the age, sex, total body weight (TBW), height (HT) and cardiac output (CO) of patients on aortic and hepatic contrast enhancement during hepatic-arterial phase (HAP) and portal venous phase (PVP) computed tomography (CT) scanning. This prospective study received institutional review board approval; prior informed consent to participate was obtained from all 168 patients. All were examined using our routine protocol; the contrast material was 600 mg/kg iodine. Cardiac output was measured with a portable electrical velocimeter within 5 minutes of starting the CT scan. We calculated contrast enhancement (per gram of iodine: [INCREMENT]HU/gI) of the abdominal aorta during the HAP and of the liver parenchyma during the PVP. We performed univariate and multivariate linear regression analysis between all patient characteristics and the [INCREMENT]HU/gI of aortic- and liver parenchymal enhancement. Univariate linear regression analysis demonstrated statistically significant correlations between the [INCREMENT]HU/gI and the age, sex, TBW, HT, and CO (all P linear regression analysis showed that only the TBW and CO were of independent predictive value (P linear regression analysis only the TBW and CO were significantly correlated with aortic and liver parenchymal enhancement; the age, sex, and HT were not. The CO was the only independent factor affecting aortic and liver parenchymal enhancement at hepatic CT when the protocol was adjusted for the TBW.

  10. On a class of strongly degenerate and singular linear elliptic equation

    International Nuclear Information System (INIS)

    Duong Minh Duc, D.M.; Le Dung.

    1992-11-01

    We consider a class of strongly degenerate linear elliptic equation. The boundedness and the Holder regularity of the weak solutions in the weighted Sobolev-Hardy spaces will be studied. (author). 9 refs

  11. Two "dual" families of Nearly-Linear Codes over ℤ p , p odd

    NARCIS (Netherlands)

    Asch, van A.G.; Tilborg, van H.C.A.

    2001-01-01

    Since the paper by Hammons e.a. [1], various authors have shown an enormous interest in linear codes over the ring Z4. A special weight function on Z4 was introduced and by means of the so called Gray map ¿ : Z4¿Z2 2 a relation was established between linear codes over Z4 and certain interesting

  12. Potential Benefits and Harms of Intermittent Energy Restriction and Intermittent Fasting Amongst Obese, Overweight and Normal Weight Subjects—A Narrative Review of Human and Animal Evidence

    Directory of Open Access Journals (Sweden)

    Michelle Harvie

    2017-01-01

    Full Text Available Intermittent energy restriction (IER has become popular as a means of weight control amongst people who are overweight and obese, and is also undertaken by normal weight people hoping spells of marked energy restriction will optimise their health. This review summarises randomised comparisons of intermittent and isoenergetic continuous energy restriction for weight loss to manage overweight and obesity. It also summarises the potential beneficial or adverse effects of IER on body composition, adipose stores and metabolic effects from human studies, including studies amongst normal weight subjects and relevant animal experimentation. Six small short term (<6 month studies amongst overweight or obese individuals indicate that intermittent energy restriction is equal to continuous restriction for weight loss, with one study reporting greater reductions in body fat, and two studies reporting greater reductions in HOMA insulin resistance in response to IER, with no obvious evidence of harm. Studies amongst normal weight subjects and different animal models highlight the potential beneficial and adverse effects of intermittent compared to continuous energy restriction on ectopic and visceral fat stores, adipocyte size, insulin resistance, and metabolic flexibility. The longer term benefits or harms of IER amongst people who are overweight or obese, and particularly amongst normal weight subjects, is not known and is a priority for further investigation.

  13. Potential Benefits and Harms of Intermittent Energy Restriction and Intermittent Fasting Amongst Obese, Overweight and Normal Weight Subjects-A Narrative Review of Human and Animal Evidence.

    Science.gov (United States)

    Harvie, Michelle; Howell, Anthony

    2017-01-19

    Intermittent energy restriction (IER) has become popular as a means of weight control amongst people who are overweight and obese, and is also undertaken by normal weight people hoping spells of marked energy restriction will optimise their health. This review summarises randomised comparisons of intermittent and isoenergetic continuous energy restriction for weight loss to manage overweight and obesity. It also summarises the potential beneficial or adverse effects of IER on body composition, adipose stores and metabolic effects from human studies, including studies amongst normal weight subjects and relevant animal experimentation. Six small short term (<6 month) studies amongst overweight or obese individuals indicate that intermittent energy restriction is equal to continuous restriction for weight loss, with one study reporting greater reductions in body fat, and two studies reporting greater reductions in HOMA insulin resistance in response to IER, with no obvious evidence of harm. Studies amongst normal weight subjects and different animal models highlight the potential beneficial and adverse effects of intermittent compared to continuous energy restriction on ectopic and visceral fat stores, adipocyte size, insulin resistance, and metabolic flexibility. The longer term benefits or harms of IER amongst people who are overweight or obese, and particularly amongst normal weight subjects, is not known and is a priority for further investigation.

  14. Potential Benefits and Harms of Intermittent Energy Restriction and Intermittent Fasting Amongst Obese, Overweight and Normal Weight Subjects—A Narrative Review of Human and Animal Evidence

    Science.gov (United States)

    Harvie, Michelle; Howell, Anthony

    2017-01-01

    Intermittent energy restriction (IER) has become popular as a means of weight control amongst people who are overweight and obese, and is also undertaken by normal weight people hoping spells of marked energy restriction will optimise their health. This review summarises randomised comparisons of intermittent and isoenergetic continuous energy restriction for weight loss to manage overweight and obesity. It also summarises the potential beneficial or adverse effects of IER on body composition, adipose stores and metabolic effects from human studies, including studies amongst normal weight subjects and relevant animal experimentation. Six small short term (obese individuals indicate that intermittent energy restriction is equal to continuous restriction for weight loss, with one study reporting greater reductions in body fat, and two studies reporting greater reductions in HOMA insulin resistance in response to IER, with no obvious evidence of harm. Studies amongst normal weight subjects and different animal models highlight the potential beneficial and adverse effects of intermittent compared to continuous energy restriction on ectopic and visceral fat stores, adipocyte size, insulin resistance, and metabolic flexibility. The longer term benefits or harms of IER amongst people who are overweight or obese, and particularly amongst normal weight subjects, is not known and is a priority for further investigation. PMID:28106818

  15. Calibration of low molecular weight polypeptides by sodium dodecylsulphate polyacrylamide gel electrophoresis

    International Nuclear Information System (INIS)

    Glyn, M.C.P.; Bull, J.; Wright, R.

    1982-01-01

    Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) is a technique commonly used in determining molecular weights of large proteins and peptides. This technique is used to analyse viral peptides, available in amounts too small to be monitored by an ultraviolet spectrophotometer. An experiment is described (with the limiting factor to use the SDS-PAGE technique), to determine the molecular weight peptides and the results are given to fit the linear relationship log M=4.286 - 0.42 V(e)/V(o). The results given by the SDS-PAGE system, described in the article, show that the experimental values describe a linear relationship with good resolution of low molecular weight peptides in the range 3 000 to 14 000 and that a partial cyanogen bromide digest of cytochrome c is suitable for calibration standards

  16. LINEAR2007, Linear-Linear Interpolation of ENDF Format Cross-Sections

    International Nuclear Information System (INIS)

    2007-01-01

    1 - Description of program or function: LINEAR converts evaluated cross sections in the ENDF/B format into a tabular form that is subject to linear-linear interpolation in energy and cross section. The code also thins tables of cross sections already in that form. Codes used subsequently need thus to consider only linear-linear data. IAEA1311/15: This version include the updates up to January 30, 2007. Changes in ENDF/B-VII Format and procedures, as well as the evaluations themselves, make it impossible for versions of the ENDF/B pre-processing codes earlier than PREPRO 2007 (2007 Version) to accurately process current ENDF/B-VII evaluations. The present code can handle all existing ENDF/B-VI evaluations through release 8, which will be the last release of ENDF/B-VI. Modifications from previous versions: - Linear VERS. 2007-1 (JAN. 2007): checked against all ENDF/B-VII; increased page size from 60,000 to 600,000 points 2 - Method of solution: Each section of data is considered separately. Each section of File 3, 23, and 27 data consists of a table of cross section versus energy with any of five interpolation laws. LINEAR will replace each section with a new table of energy versus cross section data in which the interpolation law is always linear in energy and cross section. The histogram (constant cross section between two energies) interpolation law is converted to linear-linear by substituting two points for each initial point. The linear-linear is not altered. For the log-linear, linear-log and log- log laws, the cross section data are converted to linear by an interval halving algorithm. Each interval is divided in half until the value at the middle of the interval can be approximated by linear-linear interpolation to within a given accuracy. The LINEAR program uses a multipoint fractional error thinning algorithm to minimize the size of each cross section table

  17. Stochastic modelling of optimum initial body weight, daily weight gain and effect of genetic changes in ovulation rate and age at sexual maturity on total egg production of broiler breeders.

    Science.gov (United States)

    Alvarez, R; Hocking, P M

    2009-01-01

    1. A model that simulates the total production of eggs (TEP) in broiler breeders was used to predict the optimum initial (20 week) body weight (IBWexp), daily weight gains from 20 to 30 (DWGexp(20-30)) and 31 to 62 weeks of age (DWGexp(31-62)), age at photostimulation (affecting age at first egg, AFEexp), coefficients of variation of initial body weight (CV-IBWexp) and age at first egg (CV-AFEexp), and the effect of genetically increasing the numbers of yellow follicles at the onset of lay. 2. The results suggest that TEP in broiler breeders is very sensitive to changes in body weight gain during the first 10 weeks of the production period and body weight at the start of egg production, whereas changes in body weight gain after peak rate of lay showed only minor effects on TEP. Increasing CV-IBWexp was associated with a linear decrease in the mean and increased variability of TEP. 3. Decreasing AFEexp was negatively associated with TEP, whereas higher CV-AFEexp increased variability of TEP and had a trivial affect on the mean. 4. Results of the simulation suggested that reducing ovarian yellow follicle numbers by means of genetic selection could reduce the degree of feed restriction currently used in broiler breeder commercial stocks while maintaining total egg production. Higher numbers of yellow follicles associated with selection for higher growth rate would not result in lower egg production if the body weight target was maintained at the currently recommended commercial level and the effect on TEP of increasing the target in proportion to potential body weight may be relatively small.

  18. Future Linear Colliders: Detector R&D, Jet Reconstruction and Top Physics Potential

    CERN Document Server

    AUTHOR|(CDS)2098729; Ros Martinez, Eduardo

    During the 20th century, discoveries and measurements at colliders, combined with progress in theoretical physics, allowed us to formulate the Standard Model of the in- teractions between the constituents of matter. Today, there are two advanced projects for a new installation that will collide electrons and positrons covering an energy range from several hundreds of GeV to the multi-TeV scale, the International Linear Collider (ILC) and the Compact Linear Collider (CLIC). These Future Linear Colliders give the opportunity to study the top quark with unprecedented precision. Measurements of top quark properties are of special interest, as the top quark is the heaviest ele- mentary particle of the SM. Precision measurements of top quark properties at e+e colliders promise therefore to be highly sensitive to physics beyond the SM. This thesis has three complementary parts. The first is dedicated to the R&D of the ILD detector concept for future e+e- colliders, more precisely, the innermost region of the de...

  19. Electronic excitation of atoms and molecules by electron impact in a linear algebraic, separable potential approach

    International Nuclear Information System (INIS)

    Collins, L.A.; Schneider, B.I.

    1984-01-01

    The linear algebraic, separable potential approach is applied to the electronic excitation of atoms and molecules by electron impact. By representing the exchange and off-diagonal direct terms on a basis, the standard set of coupled inelastic equations is reduced to a set of elastic inhomogeneous equations. The procedure greatly simplifies the formulation by allowing a large portion of the problem to be handled by standard bound-state techniques and by greatly reducing the order of the scattering equations that must be solved. Application is made to the excitation of atomic hydrogen in the three-state close-coupling (1s, 2s, 2p) approximation. (author)

  20. On non-linear dynamics and an optimal control synthesis of the action potential of membranes (ideal and non-ideal cases) of the Hodgkin-Huxley (HH) mathematical model

    International Nuclear Information System (INIS)

    Chavarette, Fabio Roberto; Balthazar, Jose Manoel; Rafikov, Marat; Hermini, Helder Anibal

    2009-01-01

    In this paper, we have studied the plasmatic membrane behavior using an electric circuit developed by Hodgkin and Huxley in 1952 and have dealt with the variation of the amount of time related to the potassium and sodium conductances in the squid axon. They developed differential equations for the propagation of electric signals; the dynamics of the Hodgkin-Huxley model have been extensively studied both from the view point of its their biological implications and as a test bed for numerical methods, which can be applied to more complex models. Recently, an irregular chaotic movement of the action potential of the membrane was observed for a number of techniques of control with the objective to stabilize the variation of this potential. This paper analyzes the non-linear dynamics of the Hodgkin-Huxley mathematical model, and we present some modifications in the governing equations of the system in order to make it a non-ideal one (taking into account that the energy source has a limited power supply). We also developed an optimal linear control design for the action potential of membranes. Here, we discuss the conditions that allow the use of control linear feedback for this kind of non-linear system.

  1. TFAP2B -Dietary Protein and Glycemic Index Interactions and Weight Maintenance after Weight Loss in the DiOGenes Trial

    DEFF Research Database (Denmark)

    Stocks, Tanja; Ängquist, Lars Henrik; Hager, Jörg

    2013-01-01

    Background: TFAP2B rs987237 is associated with obesity and has shown interaction with the dietary fat-to-carbohydrate ratio, which has an effect on weight loss. We investigated interactions between rs987237 and protein-to-carbohydrate ratio or glycemic index (GI) in relation to weight maintenance...... percentage from fat: either low-protein/low-GI, low-protein/high-GI, high-protein/low-GI, or high-protein/high-GI diets, or a control diet for a 6-month weight maintenance period. Using linear regression analyses and additive genetic models, we investigated main and dietary interaction effects of TFAP2B rs...... diverge depending on the nutritional state. © 2013 S. Karger AG, Basel....

  2. The weight hierarchies and chain condition of a class of codes from varieties over finite fields

    Science.gov (United States)

    Wu, Xinen; Feng, Gui-Liang; Rao, T. R. N.

    1996-01-01

    The generalized Hamming weights of linear codes were first introduced by Wei. These are fundamental parameters related to the minimal overlap structures of the subcodes and very useful in several fields. It was found that the chain condition of a linear code is convenient in studying the generalized Hamming weights of the product codes. In this paper we consider a class of codes defined over some varieties in projective spaces over finite fields, whose generalized Hamming weights can be determined by studying the orbits of subspaces of the projective spaces under the actions of classical groups over finite fields, i.e., the symplectic groups, the unitary groups and orthogonal groups. We give the weight hierarchies and generalized weight spectra of the codes from Hermitian varieties and prove that the codes satisfy the chain condition.

  3. Molecular weight changes induced in an anionic polydimethylsiloxane by gamma irradiation in vacuum

    International Nuclear Information System (INIS)

    Satti, Angel J.; Andreucetti, Noemi A.; Ciolino, Andres E.; Vitale, Cristian; Sarmoria, Claudia; Valles, Enrique M.

    2010-01-01

    An anionic almost monodisperse linear polydimethylsiloxane (PDMS) was subjected to gamma irradiation under vacuum at room temperature. The molecular weight changes induced by the radiation process have been investigated using size exclusion chromatography (SEC) with refraction index (RI) and multi angle laser light scattering (MALLS) detectors, to obtain the number and weight average molecular weights of the irradiated samples. The analysis of the data indicates that crosslinking reactions predominated over scission reactions. The results obtained by an SEC-RI have confirmed the presence of small, but measurable amounts of scission. A previously developed mathematical model of the irradiation process that accounts for simultaneous scission and crosslinking and allows for both H- and Y-crosslinks, fitted well the measured molecular weight data. This prediction is in accordance with the experimental data obtained by 29 Si-Nuclear Magnetic Resonance spectroscopy (NMR) and previously reported data for commercial linear PDMS ().

  4. Meat quality and cut yield of pigs slaughtered over 100kg live weight

    Directory of Open Access Journals (Sweden)

    T.M. Bertol

    2015-08-01

    Full Text Available Meat quality and cut yield of pigs slaughtered between 100 and 150kg live weight were evaluated. Pigs (417 Agroceres PIC barrows and gilts were fed a daily allowance of 2.8kg per head from 80kg until 100.71±0.85, 118.58±0.99, 134.07±1.18 or 143.90±1.24kg live weight. Seventy-one pigs were used for the evaluation of primal and subprimal cuts. There was no interaction between sex and slaughter weight for any of the evaluated parameters. Ham, shoulder, and loin weights linearly increased (P<0.01; R2: 84.3-93.2% with increasing slaughter weight, which, however, had little effect on primal cuts meat yield. Increasing slaughter weight promoted a linear (P<0.05 and a quadratic (P<0.01 increase of red/green coordinate (a* value of the loin and ham, respectively. Shear force showed a quadratic response (P<0.05, with minimum value estimated at 122kg slaughter weight. It was concluded that, under the applied management, increasing slaughter weight increased the volume of meat, but had little effect on meat yield. The meat of pigs slaughtered at heavier weights showed more intense red color and the same intramuscular fat content as lighter pigs, while tenderness was slightly affected.

  5. High Birth Weight Increases the Risk for Bone Tumor: A Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Songfeng Chen

    2015-09-01

    Full Text Available There have been several epidemiologic studies on the relationship between high birth weight and the risk for bone tumor in the past decades. However, due to the rarity of bone tumors, the sample size of individual studies was generally too small for reliable conclusions. Therefore, we have performed a meta-analysis to pool all published data on electronic databases with the purpose to clarify the potential relationship. According to the inclusion and exclusion criteria, 18 independent studies with more than 2796 cases were included. As a result, high birth weight was found to increase the risk for bone tumor with an Odds Ratio (OR of 1.13, with the 95% confidence interval (95% CI ranging from 1.01 to 1.27. The OR of bone tumor for an increase of 500 gram of birth weight was 1.01 (95% CI 1.00–1.02; p = 0.048 for linear trend. Interestingly, individuals with high birth weight had a greater risk for osteosarcoma (OR = 1.22, 95% CI 1.06–1.40, p = 0.006 than those with normal birth weight. In addition, in the subgroup analysis by geographical region, elevated risk was detected among Europeans (OR = 1.14, 95% CI 1.00–1.29, p = 0.049. The present meta-analysis supported a positive association between high birth weight and bone tumor risk.

  6. Ab initio optical potentials applied to low-energy e-H2 and e-N2 collisions in the linear-algebraic approach

    International Nuclear Information System (INIS)

    Schneider, B.I.; Collins, L.A.

    1983-01-01

    We propose a method for constructing an effective optical potential through which correlation effects can be introduced into the electron-molecule scattering formulation. The optical potential is based on a nonperturbative, Feshbach projection-operator procedure and is evaluated on an L 2 basis. The optical potential is incorporated into the scattering equations by means of a separable expansion, and the resulting scattering equations are solved by a linear-algebraic method based on the integral-equation formulation. We report the results of scattering calculations, which include polarization effects, for low-energy e-H 2 and e-N 2 collisions. The agreement with other theoretical and with experimental results is quite good

  7. Inhomogeneous linear equation in Rota-Baxter algebra

    OpenAIRE

    Pietrzkowski, Gabriel

    2014-01-01

    We consider a complete filtered Rota-Baxter algebra of weight $\\lambda$ over a commutative ring. Finding the unique solution of a non-homogeneous linear algebraic equation in this algebra, we generalize Spitzer's identity in both commutative and non-commutative cases. As an application, considering the Rota-Baxter algebra of power series in one variable with q-integral as the Rota-Baxter operator, we show certain Eulerian identities.

  8. An Improved Isotropic Periodic Sum Method That Uses Linear Combinations of Basis Potentials

    KAUST Repository

    Takahashi, Kazuaki Z.; Narumi, Tetsu; Suh, Donguk; Yasuoka, Kenji

    2012-01-01

    Isotropic periodic sum (IPS) is a technique that calculates long-range interactions differently than conventional lattice sum methods. The difference between IPS and lattice sum methods lies in the shape and distribution of remote images for long-range interaction calculations. The images used in lattice sum calculations are identical to those generated from periodic boundary conditions and are discretely positioned at lattice points in space. The images for IPS calculations are "imaginary", which means they do not explicitly exist in a simulation system and are distributed isotropically and periodically around each particle. Two different versions of the original IPS method exist. The IPSn method is applied to calculations for point charges, whereas the IPSp method calculates polar molecules. However, both IPSn and IPSp have their advantages and disadvantages in simulating bulk water or water-vapor interfacial systems. In bulk water systems, the cutoff radius effect of IPSn strongly affects the configuration, whereas IPSp does not provide adequate estimations of water-vapor interfacial systems unless very long cutoff radii are used. To extend the applicability of the IPS technique, an improved IPS method, which has better accuracy in both homogeneous and heterogeneous systems has been developed and named the linear-combination-based isotropic periodic sum (LIPS) method. This improved IPS method uses linear combinations of basis potentials. We performed molecular dynamics (MD) simulations of bulk water and water-vapor interfacial systems to evaluate the accuracy of the LIPS method. For bulk water systems, the LIPS method has better accuracy than IPSn in estimating thermodynamic and configurational properties without the countercharge assumption, which is used for IPSp. For water-vapor interfacial systems, LIPS has better accuracy than IPSp and properly estimates thermodynamic and configurational properties. In conclusion, the LIPS method can successfully estimate

  9. An Improved Isotropic Periodic Sum Method That Uses Linear Combinations of Basis Potentials

    KAUST Repository

    Takahashi, Kazuaki Z.

    2012-11-13

    Isotropic periodic sum (IPS) is a technique that calculates long-range interactions differently than conventional lattice sum methods. The difference between IPS and lattice sum methods lies in the shape and distribution of remote images for long-range interaction calculations. The images used in lattice sum calculations are identical to those generated from periodic boundary conditions and are discretely positioned at lattice points in space. The images for IPS calculations are "imaginary", which means they do not explicitly exist in a simulation system and are distributed isotropically and periodically around each particle. Two different versions of the original IPS method exist. The IPSn method is applied to calculations for point charges, whereas the IPSp method calculates polar molecules. However, both IPSn and IPSp have their advantages and disadvantages in simulating bulk water or water-vapor interfacial systems. In bulk water systems, the cutoff radius effect of IPSn strongly affects the configuration, whereas IPSp does not provide adequate estimations of water-vapor interfacial systems unless very long cutoff radii are used. To extend the applicability of the IPS technique, an improved IPS method, which has better accuracy in both homogeneous and heterogeneous systems has been developed and named the linear-combination-based isotropic periodic sum (LIPS) method. This improved IPS method uses linear combinations of basis potentials. We performed molecular dynamics (MD) simulations of bulk water and water-vapor interfacial systems to evaluate the accuracy of the LIPS method. For bulk water systems, the LIPS method has better accuracy than IPSn in estimating thermodynamic and configurational properties without the countercharge assumption, which is used for IPSp. For water-vapor interfacial systems, LIPS has better accuracy than IPSp and properly estimates thermodynamic and configurational properties. In conclusion, the LIPS method can successfully estimate

  10. On the Convergence of Piecewise Linear Strategic Interaction Dynamics on Networks

    KAUST Repository

    Gharesifard, Bahman; Touri, Behrouz; Basar, Tamer; Shamma, Jeff S.

    2015-01-01

    We prove that the piecewise linear best-response dynamical systems of strategic interactions are asymptotically convergent to their set of equilibria on any weighted undirected graph. We study various features of these dynamical systems, including

  11. Total and Trimester-Specific Gestational Weight Gain and Offspring Birth and Early Childhood Weight

    DEFF Research Database (Denmark)

    Scheers Andersson, Elina; Silventoinen, Karri; Tynelius, Per

    2016-01-01

    Gestational weight gain (GWG) has in numerous studies been associated with offspring birth weight (BW) and childhood weight. However, these associations might be explained by genetic confounding as offspring inherit their mother's genetic potential to gain weight. Furthermore, little is known about...... whether particular periods of pregnancy could influence offspring body weight differently. We therefore aimed to explore total and trimester-specific effects of GWG in monozygotic (MZ) twin mother-pairs on their offspring's BW, weight at 1 year and body mass index (BMI) at 5 and 10 years. MZ twin mothers...... statistically weak, suggested no associations between GWG and offspring weight or BMI during infancy or childhood. Our study suggests that total, and possibly also second and third trimester, GWG are associated with offspring BW when taking shared genetic and environmental factors within twin pairs into account...

  12. Linearization Method and Linear Complexity

    Science.gov (United States)

    Tanaka, Hidema

    We focus on the relationship between the linearization method and linear complexity and show that the linearization method is another effective technique for calculating linear complexity. We analyze its effectiveness by comparing with the logic circuit method. We compare the relevant conditions and necessary computational cost with those of the Berlekamp-Massey algorithm and the Games-Chan algorithm. The significant property of a linearization method is that it needs no output sequence from a pseudo-random number generator (PRNG) because it calculates linear complexity using the algebraic expression of its algorithm. When a PRNG has n [bit] stages (registers or internal states), the necessary computational cost is smaller than O(2n). On the other hand, the Berlekamp-Massey algorithm needs O(N2) where N(≅2n) denotes period. Since existing methods calculate using the output sequence, an initial value of PRNG influences a resultant value of linear complexity. Therefore, a linear complexity is generally given as an estimate value. On the other hand, a linearization method calculates from an algorithm of PRNG, it can determine the lower bound of linear complexity.

  13. A first step toward uncovering the truth about weight tuning in deformable image registration

    NARCIS (Netherlands)

    K. Pirpinia (Kleopatra); P.A.N. Bosman (Peter); J.-J. Sonke (Jan-Jakob); M. van Herk (Marcel); T. Alderliesten (Tanja)

    2016-01-01

    textabstractDeformable image registration is currently predominantly solved by optimizing a weighted linear combination of objectives. Successfully tuning the weights associated with these objectives is not trivial, leading to trial-and-error approaches. Such an approach assumes an intuitive

  14. Understanding the Determinants of Weight-Related Quality of Life among Bariatric Surgery Candidates

    Directory of Open Access Journals (Sweden)

    Annie Tessier

    2012-01-01

    Full Text Available Obesity and its relation to quality of life are multifaceted. The purpose of this paper was to contribute evidence to support a framework for understanding the impact of obesity on quality of life in 42 morbidly obese subjects considering a wide number of potential determinants. A model of weight-related quality of life (WRQL was developed based on the Wilson-Cleary model, considering subjects' weight characteristics, arterial oxygen pressure (PaO2, walking capacity (6-minute walk test, 6MWT, health-related quality of life (HRQL; Physical and Mental Component Summaries of the SF-36 PCS/MCS, and WRQL. The model of WRQL was tested with linear regressions and a path analysis, which showed that as PaO2 at rest increased 6MWT increased. 6MWT was positively associated with the PCS, which in turn was positively related to WRQL along with the MCS. The model showed good fit and explained 38% of the variance in WRQL.

  15. Geometric Potential Assessment for ZY3-02 Triple Linear Array Imagery

    Directory of Open Access Journals (Sweden)

    Kai Xu

    2017-06-01

    Full Text Available ZiYuan3-02 (ZY3-02 is the first remote sensing satellite for the development of China’s civil space infrastructure (CCSI and the second satellite in the ZiYuan3 series; it was launched successfully on 30 May 2016, aboard the CZ-4B rocket at the Taiyuan Satellite Launch Center (TSLC in China. Core payloads of ZY3-02 include a triple linear array camera (TLC and a multi-spectral camera, and this equipment will be used to acquire space geographic information with high-resolution and stereoscopic observations. Geometric quality is a key factor that affects the performance and potential of satellite imagery. For the purpose of evaluating comprehensively the geometric potential of ZY3-02, this paper introduces the method used for geometric calibration of the TLC onboard the satellite and a model for sensor corrected (SC products that serve as basic products delivered to users. Evaluation work was conducted by making a full assessment of the geometric performance. Furthermore, images of six regions and corresponding reference data were collected to implement the geometric calibration technique and evaluate the resulting geometric accuracy. Experimental results showed that the direct location performance and internal accuracy of SC products increased remarkably after calibration, and the planimetric and vertical accuracies with relatively few ground control points (GCPs were demonstrated to be better than 2.5 m and 2 m, respectively. Additionally, the derived digital surface model (DSM accuracy was better than 3 m (RMSE for flat terrain and 5 m (RMSE for mountainous terrain. However, given that several variations such as changes in the thermal environment can alter the camera’s installation angle, geometric performance will vary with the geographical location and imaging time changes. Generally, ZY3-02 can be used for 1:50,000 stereo mapping and can produce (and update larger-scale basic geographic information products.

  16. APPLICATION OF NEURAL NETWORK ALGORITHMS FOR BPM LINEARIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Musson, John C. [JLAB; Seaton, Chad [JLAB; Spata, Mike F. [JLAB; Yan, Jianxun [JLAB

    2012-11-01

    Stripline BPM sensors contain inherent non-linearities, as a result of field distortions from the pickup elements. Many methods have been devised to facilitate corrections, often employing polynomial fitting. The cost of computation makes real-time correction difficult, particulalry when integer math is utilized. The application of neural-network technology, particularly the multi-layer perceptron algorithm, is proposed as an efficient alternative for electrode linearization. A process of supervised learning is initially used to determine the weighting coefficients, which are subsequently applied to the incoming electrode data. A non-linear layer, known as an activation layer, is responsible for the removal of saturation effects. Implementation of a perceptron in an FPGA-based software-defined radio (SDR) is presented, along with performance comparisons. In addition, efficient calculation of the sigmoidal activation function via the CORDIC algorithm is presented.

  17. Linear discriminant analysis for welding fault detection

    International Nuclear Information System (INIS)

    Li, X.; Simpson, S.W.

    2010-01-01

    This work presents a new method for real time welding fault detection in industry based on Linear Discriminant Analysis (LDA). A set of parameters was calculated from one second blocks of electrical data recorded during welding and based on control data from reference welds under good conditions, as well as faulty welds. Optimised linear combinations of the parameters were determined with LDA and tested with independent data. Short arc welds in overlap joints were studied with various power sources, shielding gases, wire diameters, and process geometries. Out-of-position faults were investigated. Application of LDA fault detection to a broad range of welding procedures was investigated using a similarity measure based on Principal Component Analysis. The measure determines which reference data are most similar to a given industrial procedure and the appropriate LDA weights are then employed. Overall, results show that Linear Discriminant Analysis gives an effective and consistent performance in real-time welding fault detection.

  18. Enhancing Linearity of Voltage Controlled Oscillator Thermistor Signal Conditioning Circuit Using Linear Search

    Science.gov (United States)

    Rana, K. P. S.; Kumar, Vineet; Prasad, Tapan

    2018-02-01

    Temperature to Frequency Converters (TFCs) are potential signal conditioning circuits (SCCs) usually employed in temperature measurements using thermistors. A NE/SE-566 based SCC has been recently used in several reported works as TFC. Application of NE/SE-566 based SCC requires a mechanism for finding the optimal values of SCC parameters yielding the optimal linearity and desired sensitivity performances. Two classical methods, namely, inflection point and three point have been employed for this task. In this work, the application of these two methods, on NE/SE-566 based SCC in TFC, is investigated in detail and the conditions for its effective usage are developed. Further, since these classical methods offer an approximate linearization of temperature and frequency relationship an application of a linear search based technique is proposed to further enhance the linearity. The implemented linear search method used results obtained from the above mentioned classical methods. The presented simulation studies, for three different industrial grade thermistors, revealed that the linearity enhancements of 21.7, 18.3 and 17.8% can be achieved over the inflection point method and 4.9, 4.7 and 4.7% over the three point method, for an input temperature range of 0-100 °C.

  19. Weight loss maintenance in relation to locus of control: The MedWeight study.

    Science.gov (United States)

    Anastasiou, Costas A; Fappa, Evaggelia; Karfopoulou, Eleni; Gkza, Anastasia; Yannakoulia, Mary

    2015-08-01

    Locus of control, i.e. the degree of an individual's belief on the control of his/her life, has been related to many health outcomes, including weight loss in overweight/obese individuals. No information is available on the impact of locus of control in maintaining weight loss. We aimed to investigate the effect of locus of control in weight loss maintenance and explore potential associations with lifestyle factors. Study participants included 239 individuals (41% males) who had lost at least 10% of body weight in the past and either maintained the loss (maintainers: weight maintenance of at least 10% of initial weight) or regained it (regainers). Locus of control was defined by a relevant multi-dimensional scale; participants were categorised to internals and externals, based on "internal" and "others" sub-scales. A significant interaction was found between locus of control and weight loss maintenance status (p locus of control. Individualised treatment, according to locus of control, may increase weight loss maintenance rates in former overweight/obese individuals. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Glucagon-like peptide-1 analogs against antipsychotic-induced weight gain: potential physiological benefits

    OpenAIRE

    Ebdrup Bjørn H; Knop Filip K; Ishøy Pelle L; Rostrup Egill; Fagerlund Birgitte; Lublin Henrik; Glenthøj Birte

    2012-01-01

    Abstract Background Antipsychotic-induced weight gain constitutes a major unresolved clinical problem which may ultimately be associated with reducing life expectancy by 25 years. Overweight is associated with brain deterioration, cognitive decline and poor quality of life, factors which are already compromised in normal weight patients with schizophrenia. Here we outline the current strategies against antipsychotic-induced weight gain, and we describe peripheral and cerebral effects of the g...

  1. Non-linear osmosis

    Science.gov (United States)

    Diamond, Jared M.

    1966-01-01

    1. The relation between osmotic gradient and rate of osmotic water flow has been measured in rabbit gall-bladder by a gravimetric procedure and by a rapid method based on streaming potentials. Streaming potentials were directly proportional to gravimetrically measured water fluxes. 2. As in many other tissues, water flow was found to vary with gradient in a markedly non-linear fashion. There was no consistent relation between the water permeability and either the direction or the rate of water flow. 3. Water flow in response to a given gradient decreased at higher osmolarities. The resistance to water flow increased linearly with osmolarity over the range 186-825 m-osM. 4. The resistance to water flow was the same when the gall-bladder separated any two bathing solutions with the same average osmolarity, regardless of the magnitude of the gradient. In other words, the rate of water flow is given by the expression (Om — Os)/[Ro′ + ½k′ (Om + Os)], where Ro′ and k′ are constants and Om and Os are the bathing solution osmolarities. 5. Of the theories advanced to explain non-linear osmosis in other tissues, flow-induced membrane deformations, unstirred layers, asymmetrical series-membrane effects, and non-osmotic effects of solutes could not explain the results. However, experimental measurements of water permeability as a function of osmolarity permitted quantitative reconstruction of the observed water flow—osmotic gradient curves. Hence non-linear osmosis in rabbit gall-bladder is due to a decrease in water permeability with increasing osmolarity. 6. The results suggest that aqueous channels in the cell membrane behave as osmometers, shrinking in concentrated solutions of impermeant molecules and thereby increasing membrane resistance to water flow. A mathematical formulation of such a membrane structure is offered. PMID:5945254

  2. Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants.

    Science.gov (United States)

    Simal-Gándara, J; Sarria-Vidal, M; Koorevaar, A; Rijk, R

    2000-08-01

    The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick oriented PP) into the food stimulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.

  3. Weighing every day matters: daily weighing improves weight loss and adoption of weight control behaviors.

    Science.gov (United States)

    Steinberg, Dori M; Bennett, Gary G; Askew, Sandy; Tate, Deborah F

    2015-04-01

    Daily weighing is emerging as the recommended self-weighing frequency for weight loss. This is likely because it improves adoption of weight control behaviors. To examine whether weighing every day is associated with greater adoption of weight control behaviors compared with less frequent weighing. Longitudinal analysis of a previously conducted 6-month randomized controlled trial. Overweight men and women in Chapel Hill, NC, participated in the intervention arm (N=47). The intervention focused on daily weighing for weight loss using an e-scale that transmitted weights to a study website, along with weekly e-mailed lessons and tailored feedback on daily weighing adherence and weight loss progress. We gathered objective data on self-weighing frequency from the e-scales. At baseline and 6 months, weight change was measured in the clinic and weight control behaviors (total items=37), dietary strategies, and calorie expenditure from physical activity were assessed via questionnaires. Calorie intake was assessed using an online 24-hour recall tool. We used χ(2) tests to examine variation in discrete weight control behaviors and linear regression models to examine differences in weight, dietary strategies, and calorie intake and expenditure by self-weighing frequency. Fifty-one percent of participants weighed every day (n=24) over 6 months. The average self-weighing frequency among those weighing less than daily (n=23) was 5.4±1.2 days per week. Daily weighers lost significantly more weight compared with those weighing less than daily (mean difference=-6.1 kg; 95% CI -10.2 to -2.1; P=0.004). The total number of weight control behaviors adopted was greater among daily weighers (17.6±7.6 vs 11.2±6.4; P=0.004). There were no differences by self-weighing frequency in dietary strategies, calorie intake, or calorie expenditure. Weighing every day led to greater adoption of weight control behaviors and produced greater weight loss compared with weighing most days of the

  4. A linear algebraic approach to electron-molecule collisions

    International Nuclear Information System (INIS)

    Collins, L.A.; Schnieder, B.I.

    1982-01-01

    The linear algebraic approach to electron-molecule collisions is examined by firstly deriving the general set of coupled integrodifferential equations that describe electron collisional processes and then describing the linear algebraic approach for obtaining a solution to the coupled equations. Application of the linear algebraic method to static-exchange, separable exchange and effective optical potential, is examined. (U.K.)

  5. Speckle Suppression by Weighted Euclidean Distance Anisotropic Diffusion

    Directory of Open Access Journals (Sweden)

    Fengcheng Guo

    2018-05-01

    Full Text Available To better reduce image speckle noise while also maintaining edge information in synthetic aperture radar (SAR images, we propose a novel anisotropic diffusion algorithm using weighted Euclidean distance (WEDAD. Presented here is a modified speckle reducing anisotropic diffusion (SRAD method, which constructs a new edge detection operator using weighted Euclidean distances. The new edge detection operator can adaptively distinguish between homogenous and heterogeneous image regions, effectively generate anisotropic diffusion coefficients for each image pixel, and filter each pixel at different scales. Additionally, the effects of two different weighting methods (Gaussian weighting and non-linear weighting of de-noising were analyzed. The effect of different adjustment coefficient settings on speckle suppression was also explored. A series of experiments were conducted using an added noise image, GF-3 SAR image, and YG-29 SAR image. The experimental results demonstrate that the proposed method can not only significantly suppress speckle, thus improving the visual effects, but also better preserve the edge information of images.

  6. Linear fixed-field multipass arcs for recirculating linear accelerators

    Directory of Open Access Journals (Sweden)

    V. S. Morozov

    2012-06-01

    Full Text Available Recirculating linear accelerators (RLA’s provide a compact and efficient way of accelerating particle beams to medium and high energies by reusing the same linac for multiple passes. In the conventional scheme, after each pass, the different energy beams coming out of the linac are separated and directed into appropriate arcs for recirculation, with each pass requiring a separate fixed-energy arc. In this paper we present a concept of an RLA return arc based on linear combined-function magnets, in which two and potentially more consecutive passes with very different energies are transported through the same string of magnets. By adjusting the dipole and quadrupole components of the constituting linear combined-function magnets, the arc is designed to be achromatic and to have zero initial and final reference orbit offsets for all transported beam energies. We demonstrate the concept by developing a design for a droplet-shaped return arc for a dogbone RLA capable of transporting two beam passes with momenta different by a factor of 2. We present the results of tracking simulations of the two passes and lay out the path to end-to-end design and simulation of a complete dogbone RLA.

  7. Potential Benefits and Harms of Intermittent Energy Restriction and Intermittent Fasting Amongst Obese, Overweight and Normal Weight Subjects—A Narrative Review of Human and Animal Evidence

    OpenAIRE

    Howell, Anthony; Harvie, Michelle

    2017-01-01

    Intermittent energy restriction (IER) has become popular as a means of weight control amongst people who are overweight and obese, and is also undertaken by normal weight people hoping spells of marked energy restriction will optimise their health. This review summarises randomised comparisons of intermittent and isoenergetic continuous energy restriction for weight loss to manage overweight and obesity. It also summarises the potential beneficial or adverse effects of IER on body composition...

  8. Deciphering groundwater potential zones in hard rock terrain using geospatial technology.

    Science.gov (United States)

    Dar, Imran A; Sankar, K; Dar, Mithas A

    2011-02-01

    Remote sensing and geographical information system (GIS) has become one of the leading tools in the field of groundwater research, which helps in assessing, monitoring, and conserving groundwater resources. This paper mainly deals with the integrated approach of remote sensing and GIS to delineate groundwater potential zones in hard rock terrain. Digitized vector maps pertaining to chosen parameters, viz. geomorphology, geology, land use/land cover, lineament, relief, and drainage, were converted to raster data using 23 m×23 m grid cell size. Moreover, curvature of the study area was also considered while manipulating the spatial data. The raster maps of these parameters were assigned to their respective theme weight and class weights. The individual theme weight was multiplied by its respective class weight and then all the raster thematic layers were aggregated in a linear combination equation in Arc Map GIS Raster Calculator module. Moreover, the weighted layers were statistically modeled to get the areal extent of groundwater prospects with respect to each thematic layer. The final result depicts the favorable prospective zones in the study area and can be helpful in better planning and management of groundwater resources especially in hard rock terrains.

  9. Linearized Navier-Stokes equations in R3: an approach in weighted Sobolev spaces

    Czech Academy of Sciences Publication Activity Database

    Amrouche, Ch.; Meslameni, M.; Nečasová, Šárka

    2014-01-01

    Roč. 7, č. 5 (2014), s. 901-916 ISSN 1937-1632 R&D Projects: GA ČR(CZ) GAP201/11/1304 Institutional support: RVO:67985840 Keywords : generalized Oseen equations * weighted Sobolev spaces * generalized solutions Subject RIV: BA - General Mathematics Impact factor: 0.567, year: 2014 http://www.aimsciences.org/journals/displayArticlesnew.jsp?paperID=9871

  10. A goal programming procedure for solving fuzzy multiobjective fractional linear programming problems

    Directory of Open Access Journals (Sweden)

    Tunjo Perić

    2014-12-01

    Full Text Available This paper presents a modification of Pal, Moitra and Maulik's goal programming procedure for fuzzy multiobjective linear fractional programming problem solving. The proposed modification of the method allows simpler solving of economic multiple objective fractional linear programming (MOFLP problems, enabling the obtained solutions to express the preferences of the decision maker defined by the objective function weights. The proposed method is tested on the production planning example.

  11. Modeling patterns in data using linear and related models

    International Nuclear Information System (INIS)

    Engelhardt, M.E.

    1996-06-01

    This report considers the use of linear models for analyzing data related to reliability and safety issues of the type usually associated with nuclear power plants. The report discusses some of the general results of linear regression analysis, such as the model assumptions and properties of the estimators of the parameters. The results are motivated with examples of operational data. Results about the important case of a linear regression model with one covariate are covered in detail. This case includes analysis of time trends. The analysis is applied with two different sets of time trend data. Diagnostic procedures and tests for the adequacy of the model are discussed. Some related methods such as weighted regression and nonlinear models are also considered. A discussion of the general linear model is also included. Appendix A gives some basic SAS programs and outputs for some of the analyses discussed in the body of the report. Appendix B is a review of some of the matrix theoretic results which are useful in the development of linear models

  12. Chest circumference and birth weight are good predictors of lung function in preschool children from an e-waste recycling area.

    Science.gov (United States)

    Zeng, Xiang; Xu, Xijin; Zhang, Yuling; Li, Weiqiu; Huo, Xia

    2017-10-01

    The purpose of this study was to investigate the associations between birth weight, chest circumference, and lung function in preschool children from e-waste exposure area. A total of 206 preschool children from Guiyu (an e-waste recycling area) and Haojiang and Xiashan (the reference areas) in China were recruited and required to undergo physical examination, blood tests, and lung function tests during the study period. Birth outcome such as birth weight and birth height were obtained by questionnaire. Children living in the e-waste-exposed area have a lower birth weight, chest circumference, height, and lung function when compare to their peers from the reference areas (all p value <0.05). Both Spearman and partial correlation analyses showed that birth weight and chest circumference were positively correlated with lung function levels including forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV 1 ). After adjustment for the potential confounders in further linear regression analyses, birth weight, and chest circumference were positively associated with lung function levels, respectively. Taken together, birth weight and chest circumference may be good predictors for lung function levels in preschool children.

  13. Variance of a potential of mean force obtained using the weighted histogram analysis method.

    Science.gov (United States)

    Cukier, Robert I

    2013-11-27

    A potential of mean force (PMF) that provides the free energy of a thermally driven system along some chosen reaction coordinate (RC) is a useful descriptor of systems characterized by complex, high dimensional potential energy surfaces. Umbrella sampling window simulations use potential energy restraints to provide more uniform sampling along a RC so that potential energy barriers that would otherwise make equilibrium sampling computationally difficult can be overcome. Combining the results from the different biased window trajectories can be accomplished using the Weighted Histogram Analysis Method (WHAM). Here, we provide an analysis of the variance of a PMF along the reaction coordinate. We assume that the potential restraints used for each window lead to Gaussian distributions for the window reaction coordinate densities and that the data sampling in each window is from an equilibrium ensemble sampled so that successive points are statistically independent. Also, we assume that neighbor window densities overlap, as required in WHAM, and that further-than-neighbor window density overlap is negligible. Then, an analytic expression for the variance of the PMF along the reaction coordinate at a desired level of spatial resolution can be generated. The variance separates into a sum over all windows with two kinds of contributions: One from the variance of the biased window density normalized by the total biased window density and the other from the variance of the local (for each window's coordinate range) PMF. Based on the desired spatial resolution of the PMF, the former variance can be minimized relative to that from the latter. The method is applied to a model system that has features of a complex energy landscape evocative of a protein with two conformational states separated by a free energy barrier along a collective reaction coordinate. The variance can be constructed from data that is already available from the WHAM PMF construction.

  14. Solution of generalized shifted linear systems with complex symmetric matrices

    International Nuclear Information System (INIS)

    Sogabe, Tomohiro; Hoshi, Takeo; Zhang, Shao-Liang; Fujiwara, Takeo

    2012-01-01

    We develop the shifted COCG method [R. Takayama, T. Hoshi, T. Sogabe, S.-L. Zhang, T. Fujiwara, Linear algebraic calculation of Green’s function for large-scale electronic structure theory, Phys. Rev. B 73 (165108) (2006) 1–9] and the shifted WQMR method [T. Sogabe, T. Hoshi, S.-L. Zhang, T. Fujiwara, On a weighted quasi-residual minimization strategy of the QMR method for solving complex symmetric shifted linear systems, Electron. Trans. Numer. Anal. 31 (2008) 126–140] for solving generalized shifted linear systems with complex symmetric matrices that arise from the electronic structure theory. The complex symmetric Lanczos process with a suitable bilinear form plays an important role in the development of the methods. The numerical examples indicate that the methods are highly attractive when the inner linear systems can efficiently be solved.

  15. Two-pole microring weight banks.

    Science.gov (United States)

    Tait, Alexander N; Wu, Allie X; Ferreira de Lima, Thomas; Nahmias, Mitchell A; Shastri, Bhavin J; Prucnal, Paul R

    2018-05-15

    Weighted addition is an elemental multi-input to single-output operation that can be implemented with high-performance photonic devices. Microring (MRR) weight banks bring programmable weighted addition to silicon photonics. Prior work showed that their channel limits are affected by coherent inter-channel effects that occur uniquely in weight banks. We fabricate two-pole designs that exploit this inter-channel interference in a way that is robust to dynamic tuning and fabrication variation. Scaling analysis predicts a channel count improvement of 3.4-fold, which is substantially greater than predicted by incoherent analysis used in conventional MRR devices. Advances in weight bank design expand the potential of reconfigurable analog photonic networks and multivariate microwave photonics.

  16. Flow fields in the supersonic through-flow fan. Comparison of the solutions of the linear potential theory and the numerical solution of the Euler equations; Choonsoku tsukaryu fan nai no nagareba. Senkei potential rironkai to Euler hoteishiki no suchikai no hikaku

    Energy Technology Data Exchange (ETDEWEB)

    Yamasaki, N; Nanba, M; Tashiro, K [Kyushu University, Fukuoka (Japan). Faculty of Engineering

    1996-03-27

    Comparison study between solutions of a linear potential theory and numerical solution of Euler equations was made for flow in a supersonic through-flow fan. In numerical fluid dynamic technique, Euler equations are solved by finite difference method under the assumption of air and perfect gas fluid, and neglected viscosity and thermal conductivity of fluid. As a result, in a linear potential theory, expansion wave was regarded as equipotential discontinuous surface, while in Euler numerical solution, it was regarded as finite pressure gradient where a wave front fans out toward downstream. The latter reflection point of shock wave on a wing existed upstream as compared with the former reflection point. The shock wave angle was dominated by Euler equations, and different from the Mach line of a linear potential theory in both angle and discontinuous quantities in front and behind. Both calculated solutions well agreed with each other until the first reflection point of the Mach line, however, thereafter the difference between them increased toward downstream. 5 refs., 5 figs., 1 tab.

  17. Final Exam Weighting as Part of Course Design

    Directory of Open Access Journals (Sweden)

    Matthew Franke

    2018-03-01

    Full Text Available The weighting of a final exam or a final assignment is an essential part of course design that is rarely discussed in pedagogical literature. Depending on the weighting, a final exam or assignment may provide unequal benefits to students depending on their prior performance in the class. Consequently, uncritical grade weighting can discount student learning, by ensuring that improved mastery of material at the semester’s end is not reflected in the course grade. Problems related to several common final exam weights are explored, as are potential solutions to unequal student outcomes made possible by uncritical grade weighting. Ultimately, this essay argues that choosing a weight for a final exam or a final assignment determines what types of student success ought to be possible in the class; therefore, instructors should assign exam weights intentionally, being fully aware of the potential benefits and problems of the weights that they choose.

  18. Parenting style as a predictor of adolescent weight and weight-related behaviors.

    Science.gov (United States)

    Berge, Jerica M; Wall, Melanie; Loth, Katie; Neumark-Sztainer, Dianne

    2010-04-01

    Current research indicates that specific parenting styles are associated with adolescent overweight, dietary intake, and physical activity; but most of the research has been cross-sectional, making it difficult to determine the temporal order of these associations. The current study adds to the previous research by examining 5-year longitudinal associations between parenting style and adolescent weight and weight-related behaviors. Data from Project EAT, a population-based study with adolescents from diverse ethnic and socioeconomic backgrounds, were used. Adolescents (N = 2,516) from 31 Minnesota schools completed in-class assessments in 1999 (Time 1) and mailed surveys in 2004 (Time 2). Multiple linear regression models were used to predict mean levels of adolescent outcomes at Time 2 from parenting style at Time 1. Time 1 maternal authoritative parenting style predicted lower body mass index in adolescent sons and daughters at Time 2. Time 1 paternal permissive parenting style predicted more fruits and vegetables intake in daughters at Time 2. Significant associations were not found between parenting style and adolescent physical activity. Findings suggest that authoritative parenting style may play a protective role related to adolescent overweight and that the dimension of warmth and/or caring in the parent-adolescent relationship may be important in relation to female adolescent healthy dietary intake. Further exploration of opposite sex parent-adolescent dyad patterns related to parenting style and adolescent weight and weight-related behaviors is warranted. Copyright 2010 Society for Adolescent Medicine. Published by Elsevier Inc. All rights reserved.

  19. MRI characterization of brown adipose tissue in obese and normal-weight children

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Jie; Rigsby, Cynthia K.; Shore, Richard M. [Ann and Robert H. Lurie Children' s Hospital of Chicago, Department of Medical Imaging, 225 E. Chicago Ave., Box 9, Chicago, IL (United States); Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Schoeneman, Samantha E. [Ann and Robert H. Lurie Children' s Hospital of Chicago, Department of Medical Imaging, 225 E. Chicago Ave., Box 9, Chicago, IL (United States); Zhang, Huiyuan [John H. Stroger, Jr. Hospital of Cook County, Collaborative Research Unit, Chicago, IL (United States); Kwon, Soyang [Ann and Robert H. Lurie Children' s Hospital of Chicago, Stanley Manne Children' s Research Institute, Chicago, IL (United States); Northwestern University, Department of Pediatrics, Feinberg School of Medicine, Chicago, IL (United States); Josefson, Jami L. [Ann and Robert H. Lurie Children' s Hospital of Chicago, Division of Endocrinology, Chicago, IL (United States); Northwestern University, Department of Pediatrics, Feinberg School of Medicine, Chicago, IL (United States)

    2015-10-15

    Brown adipose tissue (BAT) is identified in mammals as an adaptive thermogenic organ for modulation of energy expenditure and heat generation. Human BAT may be primarily composed of brown-in-white (BRITE) adipocytes and stimulation of BRITE may serve as a potential target for obesity interventions. Current imaging studies of BAT detection and characterization have been mainly limited to PET/CT. MRI is an emerging application for BAT characterization in healthy children. To exploit Dixon and diffusion-weighted MRI methods to characterize cervical-supraclavicular BAT/BRITE properties in normal-weight and obese children while accounting for pubertal status. Twenty-eight healthy children (9-15 years old) with a normal or obese body mass index participated. MRI exams were performed to characterize supraclavicular adipose tissues by measuring tissue fat percentage, T2*, tissue water mobility, and microvasculature properties. We used multivariate linear regression models to compare tissue properties between normal-weight and obese groups while accounting for pubertal status. MRI measurements of BAT/BRITE tissues in obese children showed higher fat percentage (P < 0.0001), higher T2* (P < 0.0001), and lower diffusion coefficient (P = 0.015) compared with normal-weight children. Pubertal status was a significant covariate for the T2* measurement, with higher T2* (P = 0.0087) in pubertal children compared to prepubertal children. Perfusion measurements varied by pubertal status. Compared to normal-weight children, obese prepubertal children had lower perfusion fraction (P = 0.003) and pseudo-perfusion coefficient (P = 0.048); however, obese pubertal children had higher perfusion fraction (P = 0.02) and pseudo-perfusion coefficient (P = 0.028). This study utilized chemical-shift Dixon MRI and diffusion-weighted MRI methods to characterize supraclavicular BAT/BRITE tissue properties. The multi-parametric evaluation revealed evidence of morphological differences in brown

  20. MRI characterization of brown adipose tissue in obese and normal-weight children

    International Nuclear Information System (INIS)

    Deng, Jie; Rigsby, Cynthia K.; Shore, Richard M.; Schoeneman, Samantha E.; Zhang, Huiyuan; Kwon, Soyang; Josefson, Jami L.

    2015-01-01

    Brown adipose tissue (BAT) is identified in mammals as an adaptive thermogenic organ for modulation of energy expenditure and heat generation. Human BAT may be primarily composed of brown-in-white (BRITE) adipocytes and stimulation of BRITE may serve as a potential target for obesity interventions. Current imaging studies of BAT detection and characterization have been mainly limited to PET/CT. MRI is an emerging application for BAT characterization in healthy children. To exploit Dixon and diffusion-weighted MRI methods to characterize cervical-supraclavicular BAT/BRITE properties in normal-weight and obese children while accounting for pubertal status. Twenty-eight healthy children (9-15 years old) with a normal or obese body mass index participated. MRI exams were performed to characterize supraclavicular adipose tissues by measuring tissue fat percentage, T2*, tissue water mobility, and microvasculature properties. We used multivariate linear regression models to compare tissue properties between normal-weight and obese groups while accounting for pubertal status. MRI measurements of BAT/BRITE tissues in obese children showed higher fat percentage (P < 0.0001), higher T2* (P < 0.0001), and lower diffusion coefficient (P = 0.015) compared with normal-weight children. Pubertal status was a significant covariate for the T2* measurement, with higher T2* (P = 0.0087) in pubertal children compared to prepubertal children. Perfusion measurements varied by pubertal status. Compared to normal-weight children, obese prepubertal children had lower perfusion fraction (P = 0.003) and pseudo-perfusion coefficient (P = 0.048); however, obese pubertal children had higher perfusion fraction (P = 0.02) and pseudo-perfusion coefficient (P = 0.028). This study utilized chemical-shift Dixon MRI and diffusion-weighted MRI methods to characterize supraclavicular BAT/BRITE tissue properties. The multi-parametric evaluation revealed evidence of morphological differences in brown

  1. Responses in live weight change to net energy intake in dairy cows

    DEFF Research Database (Denmark)

    Jensen, Charlotte; Østergaard, Søren; Bertilsson, Jan

    2015-01-01

    The objective of this analysis was to estimate the effect of increased energy intake on daily live weight changes during the first 100 days of lactation of primiparous and multiparous cows. A data set with 78 observations (treatment means) was compiled from 6 production trials from Denmark, Norway...... or multiparous. Feed ration energy values were recalculated by use of NorFor to obtain consistent energy expression in all trials as opposed to the varying feed evaluation systems used in original analysis of trials. Regression analysis with linear and quadratic effects were performed on live weight...... change were made by linear mixed effects model with trial as random factor. For both primiparous and multiparous cows there was an increasing curvilinear response at a decreasing rate to increased net energy intake and the daily live weight change at day 30 was negative and at day 90 it was positive...

  2. Using personality as a predictor of diet induced weight loss and weight management

    Directory of Open Access Journals (Sweden)

    Munro Irene A

    2011-11-01

    Full Text Available Abstract Background A major challenge for successful weight management is tailoring weight loss programs to individual needs. The aim of this study was to investigate whether personality traits could be used to match individuals to a compatible weight loss program that would maximize weight loss. Method Two different weight loss trials were conducted, both with a weight loss greater than 5% the measure of success. Fifty-four individuals, BMI 30-40 kg/m2, either followed a slow, healthy eating weight loss diet (HEWLD of 5000-6000 kJ/day for 12 weeks (n = 22, or a fast, very low energy diet (VLED of 3000 kJ/day for 4 weeks (n = 32. Anthropometric measurements were recorded at baseline, at the end of the weight loss period and, for VLED, at the end of 10 weeks of weight maintenance. Personality traits were measured at baseline using the Tangney Self Control Scale plus 3 of the scales from the Five Factor Model - Neuroticism, Conscientiousness and Extraversion. Results The percentage weight loss was significantly greater in VLED (-7.38% compared to HEWLD (-4.11%, (p Conclusion The personality factor, Neuroticism, was linked to successful weight loss (that is ≥ 5% with a particular weight loss treatment, suggesting that there is a potential to use measures of personality to identify appropriate weight loss/management strategies for individuals. Trial registration Australia and New Zealand Clinical Trials Register (ANZCTR: ACTRN12611000716965

  3. Solar receiver heliostat reflector having a linear drive and position information system

    Science.gov (United States)

    Horton, Richard H.

    1980-01-01

    A heliostat for a solar receiver system comprises an improved drive and control system for the heliostat reflector assembly. The heliostat reflector assembly is controllably driven in a predetermined way by a light-weight drive system so as to be angularly adjustable in both elevation and azimuth to track the sun and efficiently continuously reflect the sun's rays to a focal zone, i.e., heat receiver, which forms part of a solar energy utilization system, such as a solar energy fueled electrical power generation system. The improved drive system includes linear stepping motors which comprise low weight, low cost, electronic pulse driven components. One embodiment comprises linear stepping motors controlled by a programmed, electronic microprocessor. Another embodiment comprises a tape driven system controlled by a position control magnetic tape.

  4. A multi-dimensional dynamic linear model for monitoring slaughter pig production

    DEFF Research Database (Denmark)

    Jensen, Dan Børge; Cornou, Cecile; Toft, Nils

    Scientists and farmers still lack an efficient way to unify the large number of different types of data series, which are increasingly being generated in relation to automatic herd monitoring. Such a unifying model should be able to account for the correlations between the various types of data......, feed-and water consumption), measured at different levels of detail (individual pig and double-pen level) and with different observational frequencies (weekly and daily), using series collected for the Danish PigIT project. The presented three-dimensional model serves as a proof of concept......, resulting in a model which could potentially yield more information than can be gained from the individual components separately. Here we present such a model for monitoring slaughter pig production, in the form of a multivariate dynamic linear model. This model unifies three types of data (live weight...

  5. Impurity strength and impurity domain modulated frequency-dependent linear and second non-linear response properties of doped quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Datta, Nirmal Kumar [Department of Physics, Suri Vidyasagar College, Suri, Birbhum 731 101, West Bengal (India); Ghosh, Manas [Department of Chemistry, Physical Chemistry Section, Visva Bharati University, Santiniketan, Birbhum 731 235, West Bengal (India)

    2011-08-15

    We explore the pattern of frequency-dependent linear and second non-linear optical responses of repulsive impurity doped quantum dots harmonically confined in two dimensions. The dopant impurity potential chosen assumes a Gaussian form and it is doped into an on-center location. The quantum dot is subject to a periodically oscillating external electric field. For some fixed values of transverse magnetic field strength ({omega}{sub c}) and harmonic confinement potential ({omega}{sub 0}), the influence of impurity strength (V{sub 0}) and impurity domain ({xi}) on the diagonal components of the frequency-dependent linear ({alpha}{sub xx} and {alpha}{sub yy}) and second non-linear ({gamma}{sub xxxx} and {gamma}{sub yyyy}) responses of the dot are computed through a linear variational route. The investigations reveal that the optical responses undergo enhancement with increase in both V{sub 0} and {xi} values. However, in the limitingly small dopant strength regime one observes a drop in the optical responses with increase in V{sub 0}. A time-average rate of energy transfer to the system is often invoked to support the findings. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Linear rheology and structure of molecular bottlebrushes with short side chains

    International Nuclear Information System (INIS)

    López-Barrón, Carlos R.; Brant, Patrick; Crowther, Donna J.; Eberle, Aaron P. R.

    2015-01-01

    We investigate the microstructure and linear viscoelasticity of model molecular bottlebrushes (BBs) using rheological and small-angle X-ray and neutron scattering measurements. Our polymers have short atactic polypropylene (aPP) side chains of molecular weight ranging from 119 g/mol to 259 g/mol and narrow molecular weight distribution (M w /M n 1.02–1.05). The side chain molecular weights are a small fraction of the entanglement molecular weight of the corresponding linear polymer (M e,aPP = 7.05 kg/mol), and as such, they are unentangled. The morphology of the aPP BBs is characterized as semiflexible thick chains with small side chain interdigitation. Their dynamic master curves, obtained by time-temperature superposition, reveal two sequential relaxation processes corresponding to the segmental relaxation and the relaxation of the BB backbone. Due to the short length of the side chains, their fast relaxation could not be distinguished from the glassy relaxation. The fractional free volume is an increasing function of the side chain length (N SC ). Therefore, the glassy behavior of these polymers as well as their molecular friction and dynamic properties are influenced by their N SC values. The apparent flow activation energies are a decreasing function of N SC , and their values explain the differences in zero-shear viscosity measured at different temperatures

  7. [Search for potential gastric cancer biomarkers using low molecular weight blood plasma proteome profiling by mass spectrometry].

    Science.gov (United States)

    Shevchenko, V E; Arnotskaia, N E; Ogorodnikova, E V; Davydov, M M; Ibraev, M A; Turkin, I N; Davydov, M I

    2014-01-01

    Gastric cancer, one of the most widespread malignant tumors, still lacks reliable serum/plasma biomarkers of its early detection. In this study we have developed, unified, and tested a new methodology for search of gastric cancer biomarkers based on profiling of low molecular weight proteome (LMWP) (1-17 kDa). This approach included three main components: sample pre-fractionation, matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS), data analysis by a bioinformatics software package. Applicability and perspectives of the developed approach for detection of potential gastric cancer markers during LMWP analysis have been demonstrated using 69 plasma samples from patients with gastric cancer (stages I-IV) and 238 control samples. The study revealed peptides/polypeptides, which may be potentially used for detection of this pathology.

  8. Birth weight and neonatal adiposity prediction using fractional limb volume obtained with 3D ultrasound.

    Science.gov (United States)

    O'Connor, Clare; O'Higgins, Amy; Doolan, Anne; Segurado, Ricardo; Stuart, Bernard; Turner, Michael J; Kennelly, Máireád M

    2014-01-01

    The objective of this investigation was to study fetal thigh volume throughout gestation and explore its correlation with birth weight and neonatal body composition. This novel technique may improve birth weight prediction and lead to improved detection rates for fetal growth restriction. Fractional thigh volume (TVol) using 3D ultrasound, fetal biometry and soft tissue thickness were studied longitudinally in 42 mother-infant pairs. The percentages of neonatal body fat, fat mass and fat-free mass were determined using air displacement plethysmography. Correlation and linear regression analyses were performed. Linear regression analysis showed an association between TVol and birth weight. TVol at 33 weeks was also associated with neonatal fat-free mass. There was no correlation between TVol and neonatal fat mass. Abdominal circumference, estimated fetal weight (EFW) and EFW centile showed consistent correlations with birth weight. Thigh volume demonstrated an additional independent contribution to birth weight prediction when added to the EFW centile from the 38-week scan (p = 0.03). Fractional TVol performed at 33 weeks gestation is correlated with birth weight and neonatal lean body mass. This screening test may highlight those at risk of fetal growth restriction or macrosomia.

  9. A Large Group Decision Making Approach Based on TOPSIS Framework with Unknown Weights Information

    Directory of Open Access Journals (Sweden)

    Li Yupeng

    2017-01-01

    Full Text Available Large group decision making considering multiple attributes is imperative in many decision areas. The weights of the decision makers (DMs is difficult to obtain for the large number of DMs. To cope with this issue, an integrated multiple-attributes large group decision making framework is proposed in this article. The fuzziness and hesitation of the linguistic decision variables are described by interval-valued intuitionistic fuzzy sets. The weights of the DMs are optimized by constructing a non-linear programming model, in which the original decision matrices are aggregated by using the interval-valued intuitionistic fuzzy weighted average operator. By solving the non-linear programming model with MATLAB®, the weights of the DMs and the fuzzy comprehensive decision matrix are determined. Then the weights of the criteria are calculated based on the information entropy theory. At last, the TOPSIS framework is employed to establish the decision process. The divergence between interval-valued intuitionistic fuzzy numbers is calculated by interval-valued intuitionistic fuzzy cross entropy. A real-world case study is constructed to elaborate the feasibility and effectiveness of the proposed methodology.

  10. A piezoelectric ultrasonic linear micromotor using a slotted stator.

    Science.gov (United States)

    Yun, Cheol-Ho; Watson, Brett; Friend, James; Yeo, Leslie

    2010-08-01

    A novel ultrasonic micro linear motor that uses 1st longitudinal and 2nd bending modes, derived from a bartype stator with a rectangular slot cut through the stator length, has been proposed and designed for end-effect devices of microrobotics and bio-medical applications. The slot structure plays an important role in the motor design, and can be used not only to tune the resonance frequency of the two vibration modes but also to reduce the undesirable longitudinal coupling displacement caused by bending vibration at the end of the stator. By using finite element analysis, the optimal slot dimension to improve the driving tip motion was determined, resulting in the improvement of the motor performance. The trial linear motor, with a weight of 1.6 g, gave a maximum driving velocity of 1.12 m/s and a maximum driving force of 3.4 N. A maximum mechanical output power of 1.1 W was obtained at force of 1.63 N and velocity of 0.68 m/s. The output mechanical power per unit weight was 688 W/kg.

  11. Schur spaces and weighted spaces of type H

    African Journals Online (AJOL)

    We extend some results related to composition operators on Hv(G) to arbitrary linear operators on Hv0 (G) and Hv(G). We also give examples of rank-one operators on Hv(G) which cannot be approximated by composition operators. Keywords: Weighted Banach spaces of holomorphic functions, Schur spaces, weakly ...

  12. Measurement of basis weight by radiation gauge

    International Nuclear Information System (INIS)

    Buchnea, A.

    1981-01-01

    For accurate measurement of the basis weight (mass per unit area) of a material such as paper between a radioactive source and an ionization chamber the apparatus is calibrated by using a plurality of standards of known basis weight to provide a relationship between basis weight and the output current of the chamber which includes at least terms of the second order and preferably terms of higher orders. The major portion of the radiation path is enclosed in airtight chambers which are sufficiently rigid that the density therein is independent of ambient temperature and pressure variations. The accuracy is increased by measuring ambient temperature and pressure fluctuations, and linearly compensating for resultant density variations in the air gap through which the paper web passes. A wheel holding the standards is induced by a motor and a perforated encoding disc. (author)

  13. Enzymatic depolymerization of gum tragacanth: bifidogenic potential of low molecular weight oligosaccharides.

    Science.gov (United States)

    Gavlighi, Hassan Ahmadi; Michalak, Malwina; Meyer, Anne S; Mikkelsen, J Dalgaard

    2013-02-13

    Gum tragacanth derived from the plant "goat's horn" (Astragalus sp.) has a long history of use as a stabilizing, viscosity-enhancing agent in food emulsions. The gum contains pectinaceous arabinogalactans and fucose-substituted xylogalacturonans. In this work, gum tragacanth from Astragalus gossypinus was enzymatically depolymerized using Aspergillus niger pectinases (Pectinex BE Color). The enzymatically degraded products were divided into three molecular weight fractions via membrane separation: HAG1 10 kDa. Compositional and linkage analyses showed that these three fractions also varied with respect to composition and structural elements: HAG1 and HAG2 were enriched in arabinose, galactose, and galacturonic acid, but low in fucose and xylose, whereas HAG3 was high in (terminal) xylose, fucose, and 1,4-bonded galacturonic acid, but low in arabinose and galactose content. The growth-stimulating potential of the three enzymatically produced gum tragacanth fractions was evaluated via growth assessment on seven different probiotic strains in single-culture fermentations on Bifidobacterium longum subsp. longum (two strains), B. longum subsp. infantis (three strains), Lactobacillus acidophilus , B. lactis, and on one pathogenic strain of Clostridium perfringens . The fractions HAG1 and HAG2 consistently promoted higher growth of the probiotic strains than HAG3, especially of the three B. longum subsp. infantis strains, and the growth promotion on HAG1 and HAG2 was better than that on galactan (control). HAG3 completely inhibited the growth of the C. perfringens strain. Tragacanth gum is thus a potential source of prebiotic carbohydrates that exert no viscosity effects and which may find use as natural functional food ingredients.

  14. Salivary habituation to food stimuli in successful weight loss maintainers, obese and normal-weight adults

    Science.gov (United States)

    Bond, DS; Raynor, HA; McCaffery, JM; Wing, RR

    2017-01-01

    Objective Research shows that slower habituation of salivary responses to food stimuli is related to greater energy intake and that obese (Ob) individuals habituate slower than those of normal weight (NW). No study has examined habituation rates in weight loss maintainers (WLMs) who have reduced from obese to normal weight, relative to those who are Ob or NW. Design Salivation to two baseline water trials and 10 lemon-flavored lollipop trials were studied in 14 WLMs, 15 Ob and 18 NW individuals comparable in age, gender and ethnicity. Linear mixed models were used to compare WLMs with Ob and NW groups. Results Salivation in the WLM and NW groups decreased significantly (for both P <0.005) across trials, indicative of habituation. Salivary responses in the Ob group did not habituate (P=0.46). When compared with Ob group, WLMs showed a quicker reduction in salivation (P<0.05). WLM and NW groups did not differ in habituation rate (P=0.49). Conclusions WLMs have habituation rates that are comparable to NW individuals without previous history of obesity, and show quicker habituation than those who are currently obese. These results suggest that physiological responses to food may ‘normalize’ with successful weight loss maintenance. PMID:20010900

  15. In vitro anticoagulation monitoring of low-molecular-weight heparin

    Institute of Scientific and Technical Information of China (English)

    WANG Jian-qi; SHI Xu-bo; YANG Jin-gang; HU Da-yi

    2009-01-01

    Background Although low-molecular-weight heparin has replaced unfractionated heparin to become the primary anticoagulation drug for treatment of acute coronary syndrome, there is no convenient bedside monitoring method. We explored the best laboratory monitoring method of low-molecular-weight heparins (enoxapadn, dalteparin, and nadroparin) by use of the Sonoclot coagulation analyzer to monitor the activated clotting time.Methods Atotal of 20 healthy volunteers were selected and 15 ml of fasting venous blood samples were collected and incubated. Four coagulants, kaolin, diatomite, glass bead, and magnetic stick, were used to determine the activated clotting time of the low-molecular-weight heparins at different in vitro anti-Xa factor concentrations. A correlation analysis was made to obtain the regression equation. The activated clotting time of the different low-molecular-weight heparins with the same anti-Xa factor concentration was monitored when the coagulant glass beads were applied. Results The activated clotting time measured using the glass beads, diatomite, kaolin, and magnetic stick showed a linear correlation with the concentration of nadroparin (r= 0.964, 0.966, 0.970, and 0.947, respectively). The regression equation showed that the linear slopes of different coagulants were significantly different (glass beads 230.03 s/IU,diatomite 89.91 s/IU, kaolin 50.87 s/IU, magnetic stick could not be calculated). When the concentration of the anti-Xa factor was the same for different low-molecular-weight heparins, the measured activated clotting time was different after the application of the glass bead coagulant.Conclusions The glass bead coagulant is most feasible for monitoring the in vitro anticoagulation activity of nadroparin.The different effects of different low-molecular-weight heparins on the activated clotting time may be related to the different anti-Ila activities.

  16. Nutrition Facts Use in Relation to Eating Behaviors and Healthy and Unhealthy Weight Control Behaviors.

    Science.gov (United States)

    Christoph, Mary J; Loth, Katie A; Eisenberg, Marla E; Haynos, Ann F; Larson, Nicole; Neumark-Sztainer, Dianne

    2018-03-01

    Investigate the relationship between use of Nutrition Facts labels on packaged foods and weight-related behaviors. Cross-sectional survey in 2015-2016. Young adult respondents (n = 1,817; 57% women; average age 31.0 ± 1.6 years) to the Project Eating and Activity in Teens and Young Adults-IV survey, the fourth wave of a longitudinal cohort study. Use of Nutrition Facts labels on packaged foods; healthy, unhealthy, and extreme weight control behaviors; intuitive eating; binge eating. Linear and logistic regression models were adjusted for age, ethnicity/race, education, income, and weight status. In women, greater Nutrition Facts use was associated with a 23% and 10% greater likelihood of engaging in healthy and unhealthy weight control behaviors, respectively, and a 17% greater chance of engaging in binge eating. In men, greater label use was associated with a 27% and 17% greater likelihood of engaging in healthy and unhealthy weight control behaviors, respectively, and a lower level of intuitive eating. Professionals advising patients and clients on weight management may consider possible gender differences in response to weight loss and management guidance. Since label use was related to engagement in some unhealthy behaviors in addition to healthy behaviors, it is important to consider how individuals may use labels, particularly those at risk for, or engaging in, disordered eating behaviors. Future research investigating potential relationships between Nutrition Facts use, intuitive eating, and binge eating is needed. Copyright © 2017 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

  17. Sociocultural and Familial Factors Associated with Weight Bias Internalization

    Directory of Open Access Journals (Sweden)

    Rebecca L. Pearl

    2018-04-01

    Full Text Available Background/Aims: Sociocultural and familial factors associated with weight bias internalization (WBI are currently unknown. The present study explored the relationship between interpersonal sources of weight stigma, family weight history, and WBI. Methods: Participants with obesity (N = 178, 87.6% female, 71.3% black completed questionnaires that assessed the frequency with which they experienced weight stigma from various interpersonal sources. Participants also reported the weight status of their family members and completed measures of WBI, depression, and demographics. Participant height and weight were measured to calculate body mass index (BMI. Results: Linear regression results (controlling for demographics, BMI, and depression showed that stigmatizing experiences from family and work predicted greater WBI. Experiencing weight stigma at work was associated with WBI above and beyond the effects of other sources of stigma. Participants who reported higher BMIs for their mothers had lower levels of WBI. Conclusion: Experiencing weight stigma from family and at work may heighten WBI, while having a mother with a higher BMI may be a protective factor against WBI. Prospective research is needed to understand WBI's developmental course and identify mechanisms that increase or mitigate its risk.

  18. The effects of electronic cigarette emissions on systemic cotinine levels, weight and postnatal lung growth in neonatal mice.

    Science.gov (United States)

    McGrath-Morrow, Sharon A; Hayashi, Madoka; Aherrera, Angela; Lopez, Armando; Malinina, Alla; Collaco, Joseph M; Neptune, Enid; Klein, Jonathan D; Winickoff, Jonathan P; Breysse, Patrick; Lazarus, Philip; Chen, Gang

    2015-01-01

    Electronic cigarette (E-cigarettes) emissions present a potentially new hazard to neonates through inhalation, dermal and oral contact. Exposure to nicotine containing E-cigarettes may cause significant systemic absorption in neonates due to the potential for multi-route exposure. Systemic absorption of nicotine and constituents of E-cigarette emissions may adversely impact weight and lung development in the neonate. To address these questions we exposed neonatal mice to E-cigarette emissions and measured systemic cotinine levels and alveolar lung growth. Neonatal mice were exposed to E-cigarettes for the first 10 days of life. E-cigarette cartridges contained either 1.8% nicotine in propylene glycol (PG) or PG vehicle alone. Daily weights, plasma and urine cotinine levels and lung growth using the alveolar mean linear intercept (MLI) method were measured at 10 days of life and compared to room air controls. Mice exposed to 1.8% nicotine/PG had a 13.3% decrease in total body weight compared to room air controls. Plasma cotinine levels were found to be elevated in neonatal mice exposed to 1.8% nicotine/PG E-cigarettes (mean 62.34± 3.3 ng/ml). After adjusting for sex and weight, the nicotine exposed mice were found to have modestly impaired lung growth by MLI compared to room air control mice (pE-cigarette emissions during the neonatal period can adversely impact weight gain. In addition exposure to nicotine containing E-cigarettes can cause detectable levels of systemic cotinine, diminished alveolar cell proliferation and a modest impairment in postnatal lung growth.

  19. Predictors and correlates for weight changes in patients co-treated with olanzapine and weight mitigating agents; a post-hoc analysis

    Directory of Open Access Journals (Sweden)

    Heinloth Alexandra N

    2009-03-01

    Full Text Available Abstract Background This study focuses on exploring the relationship between changes in appetite or eating behaviors and subsequent weight change for adult patients with schizophrenia or bipolar disorder treated with olanzapine and adjunctive potential weight mitigating pharmacotherapy. The aim is not to compare different weight mitigating agents, but to evaluate patients' characteristics and changes in their eating behaviors during treatment. Identification of patient subgroups with different degrees of susceptibility to the effect of weight mitigating agents during olanzapine treatment may aid clinicians in treatment decisions. Methods Data were obtained from 3 randomized, double-blind, placebo-controlled, 16-week clinical trials. Included were 158 patients with schizophrenia or bipolar disorder and a body mass index (BMI ≥ 25 kg/m2 who had received olanzapine treatment in combination with nizatidine (n = 68, sibutramine (n = 42, or amantadine (n = 48. Individual patients were analyzed for categorical weight loss ≥ 2 kg and weight gain ≥ 1 kg. Variables that were evaluated as potential predictors of weight outcomes included baseline patient characteristics, factors of the Eating Inventory, individual items of the Eating Behavior Assessment, and the Visual Analog Scale. Results Predictors/correlates of weight loss ≥ 2 kg included: high baseline BMI, low baseline interest in food, and a decrease from baseline to endpoint in appetite, hunger, or cravings for carbohydrates. Reduced cognitive restraint, increase in hunger, and increased overeating were associated with a higher probability of weight gain ≥ 1 kg. Conclusion The association between weight gain and lack of cognitive restraint in the presence of increased appetite suggests potential benefit of psychoeducational counseling in conjunction with adjunctive pharmacotherapeutic agents in limiting weight gain during antipsychotic drug therapy. Trial Registration This analysis was not

  20. Predictors and correlates for weight changes in patients co-treated with olanzapine and weight mitigating agents; a post-hoc analysis.

    Science.gov (United States)

    Stauffer, Virginia L; Lipkovich, Ilya; Hoffmann, Vicki Poole; Heinloth, Alexandra N; McGregor, H Scott; Kinon, Bruce J

    2009-03-28

    This study focuses on exploring the relationship between changes in appetite or eating behaviors and subsequent weight change for adult patients with schizophrenia or bipolar disorder treated with olanzapine and adjunctive potential weight mitigating pharmacotherapy. The aim is not to compare different weight mitigating agents, but to evaluate patients' characteristics and changes in their eating behaviors during treatment. Identification of patient subgroups with different degrees of susceptibility to the effect of weight mitigating agents during olanzapine treatment may aid clinicians in treatment decisions. Data were obtained from 3 randomized, double-blind, placebo-controlled, 16-week clinical trials. Included were 158 patients with schizophrenia or bipolar disorder and a body mass index (BMI) > or = 25 kg/m2 who had received olanzapine treatment in combination with nizatidine (n = 68), sibutramine (n = 42), or amantadine (n = 48). Individual patients were analyzed for categorical weight loss > or= 2 kg and weight gain > or = 1 kg. Variables that were evaluated as potential predictors of weight outcomes included baseline patient characteristics, factors of the Eating Inventory, individual items of the Eating Behavior Assessment, and the Visual Analog Scale. Predictors/correlates of weight loss > or = 2 kg included: high baseline BMI, low baseline interest in food, and a decrease from baseline to endpoint in appetite, hunger, or cravings for carbohydrates. Reduced cognitive restraint, increase in hunger, and increased overeating were associated with a higher probability of weight gain > or = 1 kg. The association between weight gain and lack of cognitive restraint in the presence of increased appetite suggests potential benefit of psychoeducational counseling in conjunction with adjunctive pharmacotherapeutic agents in limiting weight gain during antipsychotic drug therapy. This analysis was not a clinical trial and did not involve any medical intervention.

  1. Weight and volume estimates for aluminum-air batteries designed for electric vehicle applications

    Science.gov (United States)

    Cooper, J. F.

    1980-01-01

    The weights and volumes of reactants, electrolyte, and hardware components are estimated for an aluminum-air battery designed for a 40-kW (peak), 70-kWh aluminum-air battery. Generalized equations are derived which express battery power and energy content as functions of total anode area, aluminum-anode weight, and discharge current density. Equations are also presented which express total battery weight and volume as linear combinations of the variables, anode area and anode weight. The sizing and placement of battery components within the engine compartment of typical five-passenger vehicles is briefly discussed.

  2. Linear reversible second-order cellular automata and their first-order matrix equivalents

    International Nuclear Information System (INIS)

    Macfarlane, A J

    2004-01-01

    Linear or one-dimensional reversible second-order cellular automata, exemplified by three cases named as RCA1-3, are introduced. Displays of their evolution in discrete time steps, t=0, 1, 2, ..., from their simplest initial states and on the basis of updating rules in modulo 2 arithmetic, are presented. In these, shaded and unshaded squares denote cells whose cell variables are equal to one and zero respectively. This paper is devoted to finding general formulas for, and explicit numerical evaluations of, the weights N(t) of the states or configurations of RCA1-3, i.e. the total number of shaded cells in tth line of their displays. This is achieved by means of the replacement of RCA1-3 by the equivalent linear first-order matrix automata MCA1-3, for which the cell variables are 2x2 matrices, instead of just numbers (element of Z 2 ) as for RCA1-3. MCA1-3 are tractable because it has been possible to generalize to them the heavy duty methods already well-developed for ordinary first-order cellular automata like those of Wolfram's Rules 90 and 150. While the automata MCA1-3 are thought to be of genuine interest in their own right, with untapped further mathematical potential, their treatment has been applied here to expediting derivation of a large body of general and explicit results for N(t) for RCA1-3. Amongst explicit results obtained are formulas also for each of RCA1-3 for the total weight of the configurations of the first 2 M times, M=0, 1, 2, ..

  3. Bootstrapping Density-Weighted Average Derivatives

    DEFF Research Database (Denmark)

    Cattaneo, Matias D.; Crump, Richard K.; Jansson, Michael

    Employing the "small bandwidth" asymptotic framework of Cattaneo, Crump, and Jansson (2009), this paper studies the properties of a variety of bootstrap-based inference procedures associated with the kernel-based density-weighted averaged derivative estimator proposed by Powell, Stock, and Stoker...... (1989). In many cases validity of bootstrap-based inference procedures is found to depend crucially on whether the bandwidth sequence satisfies a particular (asymptotic linearity) condition. An exception to this rule occurs for inference procedures involving a studentized estimator employing a "robust...

  4. Expected number of real roots for random linear combinations of orthogonal polynomials associated with radial weights

    OpenAIRE

    Bayraktar, Turgay

    2017-01-01

    In this note, we obtain asymptotic expected number of real zeros for random polynomials of the form $$f_n(z)=\\sum_{j=0}^na^n_jc^n_jz^j$$ where $a^n_j$ are independent and identically distributed real random variables with bounded $(2+\\delta)$th absolute moment and the deterministic numbers $c^n_j$ are normalizing constants for the monomials $z^j$ within a weighted $L^2$-space induced by a radial weight function satisfying suitable smoothness and growth conditions.

  5. Eigenvector Weighting Function in Face Recognition

    Directory of Open Access Journals (Sweden)

    Pang Ying Han

    2011-01-01

    Full Text Available Graph-based subspace learning is a class of dimensionality reduction technique in face recognition. The technique reveals the local manifold structure of face data that hidden in the image space via a linear projection. However, the real world face data may be too complex to measure due to both external imaging noises and the intra-class variations of the face images. Hence, features which are extracted by the graph-based technique could be noisy. An appropriate weight should be imposed to the data features for better data discrimination. In this paper, a piecewise weighting function, known as Eigenvector Weighting Function (EWF, is proposed and implemented in two graph based subspace learning techniques, namely Locality Preserving Projection and Neighbourhood Preserving Embedding. Specifically, the computed projection subspace of the learning approach is decomposed into three partitions: a subspace due to intra-class variations, an intrinsic face subspace, and a subspace which is attributed to imaging noises. Projected data features are weighted differently in these subspaces to emphasize the intrinsic face subspace while penalizing the other two subspaces. Experiments on FERET and FRGC databases are conducted to show the promising performance of the proposed technique.

  6. Obesity and the labor market: A fresh look at the weight penalty.

    Science.gov (United States)

    Caliendo, Marco; Gehrsitz, Markus

    2016-12-01

    This paper applies semiparametric regression models to shed light on the relationship between body weight and labor market outcomes in Germany. We find conclusive evidence that these relationships are poorly described by linear or quadratic OLS specifications. Women's wages and employment probabilities do not follow a linear relationship and are highest at a body weight far below the clinical threshold of obesity. This indicates that looks, rather than health, is the driving force behind the adverse labor market outcomes to which overweight women are subject. Further support is lent to this notion by the fact that wage penalties for overweight and obese women are only observable in white-collar occupations. On the other hand, bigger appears to be better in the case of men, for whom employment prospects increase with weight, albeit with diminishing returns. However, underweight men in blue-collar jobs earn lower wages because they lack the muscular strength required in such occupations. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Miniature linear cooler development

    International Nuclear Information System (INIS)

    Pruitt, G.R.

    1993-01-01

    An overview is presented of the status of a family of miniature linear coolers currently under development by Hughes Aircraft Co. for use in hand held, volume limited or power limited infrared applications. These coolers, representing the latest additions to the Hughes family of TOP trademark [twin-opposed piston] linear coolers, have been fabricated and tested in three different configurations. Each configuration is designed to utilize a common compressor assembly resulting in reduced manufacturing costs. The baseline compressor has been integrated with two different expander configurations and has been operated with two different levels of input power. These various configuration combinations offer a wide range of performance and interface characteristics which may be tailored to applications requiring limited power and size without significantly compromising cooler capacity or cooldown characteristics. Key cooler characteristics and test data are summarized for three combinations of cooler configurations which are representative of the versatility of this linear cooler design. Configurations reviewed include the shortened coldfinger [1.50 to 1.75 inches long], limited input power [less than 17 Watts] for low power availability applications; the shortened coldfinger with higher input power for lightweight, higher performance applications; and coldfingers compatible with DoD 0.4 Watt Common Module coolers for wider range retrofit capability. Typical weight of these miniature linear coolers is less than 500 grams for the compressor, expander and interconnecting transfer line. Cooling capacity at 80K at room ambient conditions ranges from 400 mW to greater than 550 mW. Steady state power requirements for maintaining a heat load of 150 mW at 80K has been shown to be less than 8 Watts. Ongoing reliability growth testing is summarized including a review of the latest test article results

  8. On the null distribution of Bayes factors in linear regression

    Science.gov (United States)

    We show that under the null, the 2 log (Bayes factor) is asymptotically distributed as a weighted sum of chi-squared random variables with a shifted mean. This claim holds for Bayesian multi-linear regression with a family of conjugate priors, namely, the normal-inverse-gamma prior, the g-prior, and...

  9. Comparative study of growth and linear body measurements in Anak ...

    African Journals Online (AJOL)

    The study was designed to compare the performance of two different breeds of broilers (Anak and Hubbard) using body weight and body linear measurements. Data on a total of 200 (100 each) Anak and Hubbard broiler breeds were collected weekly and the experiment lasted for 8 weeks. The parameters investigated ...

  10. Linear Fixed-Field Multi-Pass Arcs for Recirculating Linear Accelerators

    International Nuclear Information System (INIS)

    Morozov, V.S.; Bogacz, S.A.; Roblin, Y.R.; Beard, K.B.

    2012-01-01

    Recirculating Linear Accelerators (RLA's) provide a compact and efficient way of accelerating particle beams to medium and high energies by reusing the same linac for multiple passes. In the conventional scheme, after each pass, the different energy beams coming out of the linac are separated and directed into appropriate arcs for recirculation, with each pass requiring a separate fixed-energy arc. In this paper we present a concept of an RLA return arc based on linear combined-function magnets, in which two and potentially more consecutive passes with very different energies are transported through the same string of magnets. By adjusting the dipole and quadrupole components of the constituting linear combined-function magnets, the arc is designed to be achromatic and to have zero initial and final reference orbit offsets for all transported beam energies. We demonstrate the concept by developing a design for a droplet-shaped return arc for a dog-bone RLA capable of transporting two beam passes with momenta different by a factor of two. We present the results of tracking simulations of the two passes and lay out the path to end-to-end design and simulation of a complete dog-bone RLA.

  11. Polynomial weights and code constructions

    DEFF Research Database (Denmark)

    Massey, J; Costello, D; Justesen, Jørn

    1973-01-01

    polynomial included. This fundamental property is then used as the key to a variety of code constructions including 1) a simplified derivation of the binary Reed-Muller codes and, for any primepgreater than 2, a new extensive class ofp-ary "Reed-Muller codes," 2) a new class of "repeated-root" cyclic codes...... of long constraint length binary convolutional codes derived from2^r-ary Reed-Solomon codes, and 6) a new class ofq-ary "repeated-root" constacyclic codes with an algebraic decoding algorithm.......For any nonzero elementcof a general finite fieldGF(q), it is shown that the polynomials(x - c)^i, i = 0,1,2,cdots, have the "weight-retaining" property that any linear combination of these polynomials with coefficients inGF(q)has Hamming weight at least as great as that of the minimum degree...

  12. Non-linear feedback neural networks VLSI implementations and applications

    CERN Document Server

    Ansari, Mohd Samar

    2014-01-01

    This book aims to present a viable alternative to the Hopfield Neural Network (HNN) model for analog computation. It is well known that the standard HNN suffers from problems of convergence to local minima, and requirement of a large number of neurons and synaptic weights. Therefore, improved solutions are needed. The non-linear synapse neural network (NoSyNN) is one such possibility and is discussed in detail in this book. This book also discusses the applications in computationally intensive tasks like graph coloring, ranking, and linear as well as quadratic programming. The material in the book is useful to students, researchers and academician working in the area of analog computation.

  13. Predicting non-linear dynamics by stable local learning in a recurrent spiking neural network.

    Science.gov (United States)

    Gilra, Aditya; Gerstner, Wulfram

    2017-11-27

    The brain needs to predict how the body reacts to motor commands, but how a network of spiking neurons can learn non-linear body dynamics using local, online and stable learning rules is unclear. Here, we present a supervised learning scheme for the feedforward and recurrent connections in a network of heterogeneous spiking neurons. The error in the output is fed back through fixed random connections with a negative gain, causing the network to follow the desired dynamics. The rule for Feedback-based Online Local Learning Of Weights (FOLLOW) is local in the sense that weight changes depend on the presynaptic activity and the error signal projected onto the postsynaptic neuron. We provide examples of learning linear, non-linear and chaotic dynamics, as well as the dynamics of a two-link arm. Under reasonable approximations, we show, using the Lyapunov method, that FOLLOW learning is uniformly stable, with the error going to zero asymptotically.

  14. Linear and nonlinear relationships between biodegradation potential and molecular descriptors/fragments for organic pollutants and a theoretical interpretation

    International Nuclear Information System (INIS)

    He, Jia; Qin, Weichao; Zhang, Xujia; Wen, Yang; Su, Limin; Zhao, Yuanhui

    2013-01-01

    Prediction of the biodegradability of organic pollutants is an ecologically desirable and economically feasible tool for estimating the environmental fate of chemicals. In this paper, linear and nonlinear relationships between biological oxygen demand (BOD) and molecular descriptors/fragments have been investigated for 1130 organic chemicals. Significant relationships have been observed between the simple molecular descriptors and %BOD for some homologous compounds, but not for the whole set of compounds. Electronic parameters, such as E HOMO and E LUMO , are the dominant factors affecting the biodegradability for some homologous chemicals. However, other descriptors, such as molecular weight, acid dissociation constant and polarity still have a significant impact on the biodegradation. The best global model for %BOD prediction is that developed from a chain-based fragmentation scheme. At the same time, the theoretical relationship between %BOD and molecular descriptors/fragments has been investigated, based on a first-order kinetic process. The %BOD is nonlinearly, rather than linearly, related to the descriptors. The coefficients of determination can be significantly improved by using nonlinear models for the homologous compounds and the whole data set. After analysing 1130 ready and not ready biodegradable compounds using 23 simple descriptors and various fragmentation schemes, it was revealed that biodegradation could be well predicted from a chain-based fragmentation scheme, a decision tree and a %BOD model. The models were capable of separating NRB and RB with an overall accuracy of 87.2%, 83.0% and 82.5%, respectively. The best classification model developed was a chain-based model but it used 155 fragments. The simplest model was a decision tree which only used 10 structural fragments. The effect of structures on the biodegradation has been analysed and the biodegradation pathway and mechanisms have been discussed based on activating and inactivating

  15. Examination of temperature-induced shape memory of uranium--5.3-to 6.9 weight percent niobium alloys

    International Nuclear Information System (INIS)

    Hemperly, V.C.

    1976-01-01

    The uranium-niobium alloy system was examined in the range of 5.3-to-6.9 weight percent niobium with respect to shape memory, mechanical properties, metallography, Coefficients of linear thermal expansion, and differential thermal analysis. Shape memory increased with increasing niobium levels in the study range. There were no useful correlations found between shape memory and the other tests. Coefficients of linear thermal expansion tests of as-quenched 5.8 and 6.2 weight percent niobium specimens, but not 5.3 and 6.9 weight percent niobium specimens, had a contraction component on heating, but the phenomenon was not a contributor to shape memory

  16. Genetic parameters of body weight and prolificacy in pigeons

    Directory of Open Access Journals (Sweden)

    Beaumont Catherine

    2000-07-01

    Full Text Available Abstract Genetic parameters of body weight at weaning and of prolificacy were estimated in three commercial lines of pigeons selected by BLUP (Best Linear Unbiased Prediction on both traits. The model of analysis took into account the direct genetic effects for both traits and the effect of parental permanent environment for body weight. Depending on the line considered, body weight varied from 556.7 g to 647.6 g and prolificacy ranged from 12.5 to 16.8 pigeons weaned per couple of parents per year. Heritability of body weight was high, varying between 0.46 and 0.60, and permanent environment was responsible for 6% to 9% of the total variability. On the contrary, prolificacy was poorly heritable (0.04 to 0.12. They were highly and negatively correlated (-0.77 to -0.82. Body weight showed significant genetic trends in lines B and C. No significant genetic difference could be observed between males and females for both traits.

  17. A Generalized Weight-Based Particle-In-Cell Simulation Scheme

    International Nuclear Information System (INIS)

    Lee, W.W.; Jenkins, T.G.; Ethier, S.

    2010-01-01

    A generalized weight-based particle simulation scheme suitable for simulating magnetized plasmas, where the zeroth-order inhomogeneity is important, is presented. The scheme is an extension of the perturbative simulation schemes developed earlier for particle-in-cell (PIC) simulations. The new scheme is designed to simulate both the perturbed distribution ((delta)f) and the full distribution (full-F) within the same code. The development is based on the concept of multiscale expansion, which separates the scale lengths of the background inhomogeneity from those associated with the perturbed distributions. The potential advantage for such an arrangement is to minimize the particle noise by using (delta)f in the linear stage stage of the simulation, while retaining the flexibility of a full-F capability in the fully nonlinear stage of the development when signals associated with plasma turbulence are at a much higher level than those from the intrinsic particle noise.

  18. Assessment of Brown Bear\\'s (Ursus arctos syriacus Winter Habitat Using Geographically Weighted Regression and Generalized Linear Model in South of Iran

    Directory of Open Access Journals (Sweden)

    A. A. Zarei

    2016-03-01

    Full Text Available Winter dens are one of the important components of brown bear's (Ursus arctos syriacus habitat, affecting their reproduction and survival. Therefore identification of factors affecting the habitat selection and suitable denning areas in the conservation of our largest carnivore is necessary. We used Geographically Weighted Logistic Regression (GWLR and Generalized Linear Model (GLM for modeling suitability of denning habitat in Kouhkhom region in Fars province. In the present research, 20 dens (presence locations and 20 caves where signs of bear were not found (absence locations were used as dependent variables and six environmental factors were used for each location as independent variables. The results of GLM showed that variables of distance to settlements, altitude, and distance to water were the most important parameters affecting suitability of the brown bear's denning habitat. The results of GWLR showed the significant local variations in the relationship between occurrence of brown bear dens and the variable of distance to settlements. Based on the results of both models, suitable habitats for denning of the species are impassable areas in the mountains and inaccessible for humans.

  19. Linear Algebra and Smarandache Linear Algebra

    OpenAIRE

    Vasantha, Kandasamy

    2003-01-01

    The present book, on Smarandache linear algebra, not only studies the Smarandache analogues of linear algebra and its applications, it also aims to bridge the need for new research topics pertaining to linear algebra, purely in the algebraic sense. We have introduced Smarandache semilinear algebra, Smarandache bilinear algebra and Smarandache anti-linear algebra and their fuzzy equivalents. Moreover, in this book, we have brought out the study of linear algebra and vector spaces over finite p...

  20. The effect of genotype and birth type on gestation length and linear ...

    African Journals Online (AJOL)

    The effect of genotype and birth type on gestation length and linear body ... was conducted in Enugu State University of Science and Technology, in the then ... Weekly weights and live body measurements of the kids were recorded from ...

  1. Biochemical, Anthropometric and Lifestyle Factors Related with Weight Maintenance after Weight Loss Secondary to a Hypocaloric Mediterranean Diet.

    Science.gov (United States)

    de Luis, Daniel Antonio; Izaola, Olatz; Primo, David; Ovalle, Hilda F; Lopez, Juan Jose; Gomez, Emilia; Ortola, Ana; Aller, Rocio

    2017-01-01

    The aim of our study was to evaluate the influence of lifestyle factors and molecular biomarkers on the maintenance of the weight lost after a hypocaloric Mediterranean diet. After 3 months on a diet, patients (n = 335) remained with no controlled diet during 3 years and they were revaluated. Using linear regression, in the group of responders, we detected that a positive weight loss at 3 months, serum levels of leptin at 3 months, and each 30 min per week of physical activity were associated with weight loss maintenance. In the model with reduced weight (RW) as dependent variable, a positive weight loss at 3 months was associated with 2.4% RW (95% CI 1.31-8.11; p = 0.015), each unit of serum leptin levels at 3 months with -0.44% RW (95% CI -0.59 to -0.020; p = 0.007), each basal unit homeostasis model assessment for insulin resistance (HOMA-IR) level with -2.32% (95% CI -13.01 to -0.17; p = 0.040), and each 30 min per week of physical activity with 1.58% RW (95% CI 1.08-2.94; p = 0.020). Obese subjects who are on maintenance weight loss after a dietary intervention appear to have a better initial response during the 3 months intervention, more physical activity at 3 years, and lower basal HOMA-IR and leptin after weight loss than those who regain weight. © 2017 S. Karger AG, Basel.

  2. Coefficient of linear attenuation of beer for γ rays of 662 keV

    International Nuclear Information System (INIS)

    Ortiz A, M. D.; Cano S, D.; Vega C, H. R.

    2017-10-01

    The coefficient of linear attenuation of the beer was determined by means of a transmission experiment with a source of Cs 137 and a gamma ray spectrometer with a NaI(Tl) detector of 7.62 cm in diameter and 7.62 cm in height, using narrow geometry. The pulse height spectrum was accumulated for 1 minute of live time, 7 beer thicknesses (0.6 cm) were used. By means of linear regression by weighted squares we determined the linear attenuation coefficient whose value was μ = 0.0843 ± 0.0007 cm -1 . The coefficient of linear attenuation of water is 2.2% times greater than that of beer and to the geometry of the experimental arrangement. (Author)

  3. Recent progress on weight distributions of cyclic codes over finite fields

    Directory of Open Access Journals (Sweden)

    Hai Q. Dinh

    2015-01-01

    Full Text Available Cyclic codes are an interesting type of linear codes and have wide applications in communication and storage systems due to their efficient encoding and decoding algorithms. In coding theory it is often desirable to know the weight distribution of a cyclic code to estimate the error correcting capability and error probability. In this paper, we present the recent progress on the weight distributions of cyclic codes over finite fields, which had been determined by exponential sums. The cyclic codes with few weights which are very useful are discussed and their existence conditions are listed. Furthermore, we discuss the more general case of constacyclic codes and give some equivalences to characterize their weight distributions.

  4. Cooking fuel choices and garbage burning practices as determinants of birth weight: a cross-sectional study in Accra, Ghana

    Directory of Open Access Journals (Sweden)

    Amegah Adeladza K

    2012-10-01

    Full Text Available Abstract Background Effect of indoor air pollution (IAP on birth weight remains largely unexplored but yet purported as the most important environmental exposure for pregnant women in developing countries due to the effects of second-hand smoke. We investigated the associations between the determinants of indoor air quality in households and birth weight. Methods A cross-sectional study of 592 mothers and their newborns using postnatal services at the Korle Bu Teaching Hospital located in Accra, Ghana was conducted in 2010 to collect information on characteristics of indoor environment and other potential determinants of fetal growth. Birth weight was recorded from hospital records. Results Household cooking fuel choices and garbage burning practices were determinants of birth weight. Multivariate linear regression analysis adjusting for age, social class, marital status and gravidity of mothers, and sex of neonate resulted in a 243g (95% CI: 496, 11 and 178g (95% CI: 421, 65 reduction in birth weight for use of charcoal, and garbage burning respectively compared with use of LPG only. The estimated reductions in birth weight was not statistically significant. Applying the ordinal scale exposure parameter nonetheless revealed a significant exposure-response relationship between maternal exposures from charcoal use and garbage burning, and birth weight. Generalized linear models adjusting for confounders resulted in a 41% (risk ratio [RR] = 1.41; 95% CI: 0.62, 3.23 and 195% (RR=2.95; 95% CI: 1.10, 7.92 increase in the risk of low birth weight (LBW for use of charcoal, and garbage burning respectively compared with use of LPG only. A combination of charcoal use and household garbage burning during pregnancy on fetal growth resulted in a 429g (95% CI: 259, 599 reduction in birth weight and 316% (RR=4.16; 95% CI: 2.02, 8.59 excess risk of LBW. Sensitivity analysis performed by restricting the analysis to term births produced similar results

  5. Comparison of open-source linear programming solvers.

    Energy Technology Data Exchange (ETDEWEB)

    Gearhart, Jared Lee; Adair, Kristin Lynn; Durfee, Justin David.; Jones, Katherine A.; Martin, Nathaniel; Detry, Richard Joseph

    2013-10-01

    When developing linear programming models, issues such as budget limitations, customer requirements, or licensing may preclude the use of commercial linear programming solvers. In such cases, one option is to use an open-source linear programming solver. A survey of linear programming tools was conducted to identify potential open-source solvers. From this survey, four open-source solvers were tested using a collection of linear programming test problems and the results were compared to IBM ILOG CPLEX Optimizer (CPLEX) [1], an industry standard. The solvers considered were: COIN-OR Linear Programming (CLP) [2], [3], GNU Linear Programming Kit (GLPK) [4], lp_solve [5] and Modular In-core Nonlinear Optimization System (MINOS) [6]. As no open-source solver outperforms CPLEX, this study demonstrates the power of commercial linear programming software. CLP was found to be the top performing open-source solver considered in terms of capability and speed. GLPK also performed well but cannot match the speed of CLP or CPLEX. lp_solve and MINOS were considerably slower and encountered issues when solving several test problems.

  6. In vitro fermentation and prebiotic potential of novel low molecular weight polysaccharides derived from agar and alginate seaweeds.

    Science.gov (United States)

    Ramnani, Priya; Chitarrari, Roberto; Tuohy, Kieran; Grant, John; Hotchkiss, Sarah; Philp, Kevin; Campbell, Ross; Gill, Chris; Rowland, Ian

    2012-02-01

    Fermentation properties and prebiotic potential of novel low molecular weight polysaccharides (LMWPs) derived from agar and alginate bearing seaweeds was investigated. Ten LMWPs were supplemented to pH, temperature controlled anaerobic batch cultures inoculated with human feces from three donors, in triplicate. Microbiota changes were monitored using Fluorescent in-situ hybridization and short chain fatty acids, the fermentation end products were analysed using gas chromatography. Of the ten LMWPs tested, Gelidium seaweed CC2253 of molecular weight 64.64 KDa showed a significant increase in bifidobacterial populations from log(10) 8.06 at 0 h to log(10) 8.55 at 24 h (p = 0.018). For total bacterial populations, alginate powder CC2238 produced a significant increase from log(10) 9.01 at 0 h to log(10) 9.58 at 24 h (p = 0.032). No changes were observed in the other bacterial groups tested viz. Bacteroides, Lactobacilli/Enterococci, Eubacterium rectale/Clostridium coccoides and Clostridium histolyticum. The polysaccharides also showed significant increases in total SCFA production, particularly acetic and propionic acids, indicating that they were readily fermented. In conclusion, some LMWPs derived from agar and alginate bearing seaweeds were fermented by gut bacteria and exhibited potential to be used a novel source of prebiotics. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Connection between weighted LPC and higher-order statistics for AR model estimation

    NARCIS (Netherlands)

    Kamp, Y.; Ma, C.

    1993-01-01

    This paper establishes the relationship between a weighted linear prediction method used for robust analysis of voiced speech and the autoregressive modelling based on higher-order statistics, known as cumulants

  8. Feasibility and Potential Benefits of a Self-Monitoring Enhanced Lifestyle Intervention to Prevent Excessive Gestational Weight Gain in Women Who Are Overweight or Obese.

    Science.gov (United States)

    Shieh, Carol; Yang, Ziyi; Haas, David M; Carpenter, Janet S

    To evaluate the feasibility and potential benefits of a self-monitoring enhanced lifestyle intervention to prevent excessive gestational weight gain in women who are overweight and obese. A one-group, prospective design involving 8 weeks of healthy eating and physical activity and self-monitoring of weight, nutrition, and walking. Recruitment and enrollment in prenatal clinics and self-monitoring at home. Women (N = 22) at 14 to 24 gestational weeks, with body mass indexes of 25 to 40 kg/m 2 , without medical and psychiatric diseases that affected cognition or walking. Participants self-monitored weight and nutrition intake for the first 4 weeks and weight, nutrition intake, and walking in the second 4 weeks. Feasibility data were collected weekly (attrition, self-monitoring adherence, program safety, participant feedback) or at the end of Week 8 (satisfaction ratings). Potential benefits included weight, nutrition, and physical activity, measured at baseline (T1), the end of Week 4 (T2), or the end of Week 8 (T3). Attrition rates were 27.3% by T2 and 40.9% by T3. Adherence to log return was 100%. No adverse effects were noted, but food craving was persistent, and stress levels were high. Program satisfaction was high. Trends for improved activity and reduced trans fat consumption were seen. Our findings indicate that the intervention is worthy of further development and testing with a randomized controlled trial. Copyright © 2017 AWHONN, the Association of Women’s Health, Obstetric and Neonatal Nurses. Published by Elsevier Inc. All rights reserved.

  9. Yogurt and weight management.

    Science.gov (United States)

    Jacques, Paul F; Wang, Huifen

    2014-05-01

    A large body of observational studies and randomized controlled trials (RCTs) has examined the role of dairy products in weight loss and maintenance of healthy weight. Yogurt is a dairy product that is generally very similar to milk, but it also has some unique properties that may enhance its possible role in weight maintenance. This review summarizes the human RCT and prospective observational evidence on the relation of yogurt consumption to the management and maintenance of body weight and composition. The RCT evidence is limited to 2 small, short-term, energy-restricted trials. They both showed greater weight losses with yogurt interventions, but the difference between the yogurt intervention and the control diet was only significant in one of these trials. There are 5 prospective observational studies that have examined the association between yogurt and weight gain. The results of these studies are equivocal. Two of these studies reported that individuals with higher yogurt consumption gained less weight over time. One of these same studies also considered changes in waist circumference (WC) and showed that higher yogurt consumption was associated with smaller increases in WC. A third study was inconclusive because of low statistical power. A fourth study observed no association between changes in yogurt intake and weight gain, but the results suggested that those with the largest increases in yogurt intake during the study also had the highest increase in WC. The final study examined weight and WC change separately by sex and baseline weight status and showed benefits for both weight and WC changes for higher yogurt consumption in overweight men, but it also found that higher yogurt consumption in normal-weight women was associated with a greater increase in weight over follow-up. Potential underlying mechanisms for the action of yogurt on weight are briefly discussed.

  10. [Linear growth retardation in children under five years of age: a baseline study].

    Science.gov (United States)

    Rissin, Anete; Figueiroa, José Natal; Benício, Maria Helena D'Aquino; Batista Filho, Malaquias

    2011-10-01

    The scope of this study was to describe the prevalence of, and analyze factors associated with, linear growth retardation in children. The baseline study analyzed 2040 children under the age of five, establishing a possible association between growth delay (height/age index non-binary variables, there was a positive association with roof type and number of inhabitants per room and a negative association with income per capita, mother's schooling and birth weight. The adjusted analysis also indicated water supply, visit from the community health agent, birth delivery location, internment for diarrhea, or for pneumonia and birth weight as significant variables. Several risk factors were identified for linear growth retardation pointing to the multi-causal aspects of the problem and highlighting the need for control measures by the various hierarchical government agents.

  11. Polycystic ovary syndrome and weight management.

    Science.gov (United States)

    Moran, Lisa J; Lombard, Catherine B; Lim, Siew; Noakes, Manny; Teede, Helena J

    2010-03-01

    Polycystic ovary syndrome (PCOS) is a common condition in women of reproductive age, and has reproductive, metabolic and psychological implications. Weight gain and obesity worsen the features of PCOS, while weight loss improves the features of PCOS. While there are potential barriers to successful weight management in young women who do not suffer from PCOS, women with PCOS may experience additional barriers. Weight management strategies in younger women with or without PCOS should encompass both the prevention of excess weight gain and achieving and maintaining a reduced weight through multidisciplinary lifestyle management, comprising dietary, exercise and behavioral therapy, as well as attention to psychosocial stress and practical and physiological barriers to weight management. Further research is warranted in the examination of specific barriers to weight management in women with PCOS, as well as in the determination of optimal components of lifestyle weight management interventions in young women in order to facilitate long-term compliance.

  12. Weight status and weight-related behaviors of children commencing school.

    Science.gov (United States)

    Hardy, Louise L; King, Lesley; Hector, Debra; Lloyd, Beverley

    2012-11-01

    To describe the weight status and weight-related behaviors of children commencing school. This study is a representative cross-sectional survey of Australian children in their first year of schooling (n=1141) in 2010. Height and weight were measured, and parents reported their child's diet, physical activity and screen-time. 18.7% of children were overweight/obese. Compared with non-overweight/obese peers, overweight/obese boys were 1.73 times (95% CI 1.08, 2.79) as likely to exceed recommended screen time and 2.07 times (95% CI 1.11, 3.87) as likely to eat dinner three or more times/week in front of the TV. Overweight/obese girls were twice as likely to have a TV in their bedroom (OR 2.00, 95% CI 1.12, 3.59) and usually be rewarded with sweets for good behavior (OR 1.96, 95% CI 1.09, 3.51) and were 1.65 times as likely to be inactive (95% CI 1.08, 2.55). We showed that many children begin school with established weight-related behaviors that occur in the home environment. The inclusion of parents and the home environment in intervention strategies will be important to support changes to reduce childhood obesity. The weight status and weight-related behaviors of children entering school may potentially be a general indicator of the overall effectiveness of obesity prevention interventions among preschool-aged children. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

  13. VOLUME ESTIMATIONS FOR COMBINED FREE-WEIGHT AND RUBBER-BAND RESISTANCE EXERCISE

    OpenAIRE

    C. Shoepe, Todd; Vejarano, Gustavo; P. Reyes, Nathan; M. Gobreial, Nicole; M. Ricci, Jeanette

    2017-01-01

    Volume, or the total work performed during resistance training is one of the vital variables of resistance exercise programming. The most common definition in use by practitioners is sets x reps x external weight. While appropriate for linear loading incurred through free-weight resistance exercise, this inadequately addresses the nonlinear loading incurred with rubber resistance, a relatively new loading technique. The purpose of this investigation was to derive a theoretical model to descri...

  14. Single image super-resolution using locally adaptive multiple linear regression.

    Science.gov (United States)

    Yu, Soohwan; Kang, Wonseok; Ko, Seungyong; Paik, Joonki

    2015-12-01

    This paper presents a regularized superresolution (SR) reconstruction method using locally adaptive multiple linear regression to overcome the limitation of spatial resolution of digital images. In order to make the SR problem better-posed, the proposed method incorporates the locally adaptive multiple linear regression into the regularization process as a local prior. The local regularization prior assumes that the target high-resolution (HR) pixel is generated by a linear combination of similar pixels in differently scaled patches and optimum weight parameters. In addition, we adapt a modified version of the nonlocal means filter as a smoothness prior to utilize the patch redundancy. Experimental results show that the proposed algorithm better restores HR images than existing state-of-the-art methods in the sense of the most objective measures in the literature.

  15. Weighted linear regression using D2H and D2 as the independent variables

    Science.gov (United States)

    Hans T. Schreuder; Michael S. Williams

    1998-01-01

    Several error structures for weighted regression equations used for predicting volume were examined for 2 large data sets of felled and standing loblolly pine trees (Pinus taeda L.). The generally accepted model with variance of error proportional to the value of the covariate squared ( D2H = diameter squared times height or D...

  16. Adolescent Snacking Behaviors Are Associated with Dietary Intake and Weight Status.

    Science.gov (United States)

    Larson, Nicole I; Miller, Jonathan M; Watts, Allison W; Story, Mary T; Neumark-Sztainer, Dianne R

    2016-07-01

    Most adolescents consume ≥1 snack/d; exploring the relevance of snacking patterns for overall diet and weight status is important to guide dietary counseling and public health strategies for obesity prevention. This study examined intake of common energy-dense snack foods, total number of snacks consumed, frequency of consuming snacks prepared away from home, and frequency of snacking while watching television in adolescents and how these behaviors may be linked to diet and weight status. Relations were examined with attention to potential confounders that may help explain the mixed findings of previous research. Survey measures of snacking behavior, a food-frequency questionnaire, and anthropometric measurements were completed by 2793 adolescents (53.2% girls, mean age = 14.4 y) in Minneapolis-St. Paul school classrooms in 2009-2010. Linear regression was used to examine associations with adjustment for sociodemographic characteristics and other potential confounding factors, such as meal skipping, underreporting energy intake, dieting to lose weight, and physical activity. Adolescents reported consuming a mean of 2.2 energy-dense snack food servings/d and 4.3 snacks/d and purchasing snacks prepared away from home on 3.2 occasions/wk. More than two-thirds of adolescents reported that they sometimes, usually, or always consumed a snack while watching television. The measures of snacking were directly associated (P snack food servings were not related to sugar-sweetened beverage intake. A direct relation between daily servings of energy-dense snack foods and body mass index (BMI) z score was found; however, the snacking behaviors were inversely related to BMI z score (P snack consumption is a risk factor for poor diet, but unless energy-dense foods are consumed, snacking does not consistently contribute to overweight in US adolescents. © 2016 American Society for Nutrition.

  17. Non-linear regime shifts in Holocene Asian monsoon variability: potential impacts on cultural change and migratory patterns

    Science.gov (United States)

    Donges, J. F.; Donner, R. V.; Marwan, N.; Breitenbach, S. F. M.; Rehfeld, K.; Kurths, J.

    2015-05-01

    The Asian monsoon system is an important tipping element in Earth's climate with a large impact on human societies in the past and present. In light of the potentially severe impacts of present and future anthropogenic climate change on Asian hydrology, it is vital to understand the forcing mechanisms of past climatic regime shifts in the Asian monsoon domain. Here we use novel recurrence network analysis techniques for detecting episodes with pronounced non-linear changes in Holocene Asian monsoon dynamics recorded in speleothems from caves distributed throughout the major branches of the Asian monsoon system. A newly developed multi-proxy methodology explicitly considers dating uncertainties with the COPRA (COnstructing Proxy Records from Age models) approach and allows for detection of continental-scale regime shifts in the complexity of monsoon dynamics. Several epochs are characterised by non-linear regime shifts in Asian monsoon variability, including the periods around 8.5-7.9, 5.7-5.0, 4.1-3.7, and 3.0-2.4 ka BP. The timing of these regime shifts is consistent with known episodes of Holocene rapid climate change (RCC) and high-latitude Bond events. Additionally, we observe a previously rarely reported non-linear regime shift around 7.3 ka BP, a timing that matches the typical 1.0-1.5 ky return intervals of Bond events. A detailed review of previously suggested links between Holocene climatic changes in the Asian monsoon domain and the archaeological record indicates that, in addition to previously considered longer-term changes in mean monsoon intensity and other climatic parameters, regime shifts in monsoon complexity might have played an important role as drivers of migration, pronounced cultural changes, and the collapse of ancient human societies.

  18. From spiking neuron models to linear-nonlinear models.

    Science.gov (United States)

    Ostojic, Srdjan; Brunel, Nicolas

    2011-01-20

    Neurons transform time-varying inputs into action potentials emitted stochastically at a time dependent rate. The mapping from current input to output firing rate is often represented with the help of phenomenological models such as the linear-nonlinear (LN) cascade, in which the output firing rate is estimated by applying to the input successively a linear temporal filter and a static non-linear transformation. These simplified models leave out the biophysical details of action potential generation. It is not a priori clear to which extent the input-output mapping of biophysically more realistic, spiking neuron models can be reduced to a simple linear-nonlinear cascade. Here we investigate this question for the leaky integrate-and-fire (LIF), exponential integrate-and-fire (EIF) and conductance-based Wang-Buzsáki models in presence of background synaptic activity. We exploit available analytic results for these models to determine the corresponding linear filter and static non-linearity in a parameter-free form. We show that the obtained functions are identical to the linear filter and static non-linearity determined using standard reverse correlation analysis. We then quantitatively compare the output of the corresponding linear-nonlinear cascade with numerical simulations of spiking neurons, systematically varying the parameters of input signal and background noise. We find that the LN cascade provides accurate estimates of the firing rates of spiking neurons in most of parameter space. For the EIF and Wang-Buzsáki models, we show that the LN cascade can be reduced to a firing rate model, the timescale of which we determine analytically. Finally we introduce an adaptive timescale rate model in which the timescale of the linear filter depends on the instantaneous firing rate. This model leads to highly accurate estimates of instantaneous firing rates.

  19. Diffusion phenomenon for linear dissipative wave equations

    KAUST Repository

    Said-Houari, Belkacem

    2012-01-01

    In this paper we prove the diffusion phenomenon for the linear wave equation. To derive the diffusion phenomenon, a new method is used. In fact, for initial data in some weighted spaces, we prove that for {equation presented} decays with the rate {equation presented} [0,1] faster than that of either u or v, where u is the solution of the linear wave equation with initial data {equation presented} [0,1], and v is the solution of the related heat equation with initial data v 0 = u 0 + u 1. This result improves the result in H. Yang and A. Milani [Bull. Sci. Math. 124 (2000), 415-433] in the sense that, under the above restriction on the initial data, the decay rate given in that paper can be improved by t -γ/2. © European Mathematical Society.

  20. Bound-state Dirac eigenvalues for scalar potentials

    International Nuclear Information System (INIS)

    Ram, B.; Arafah, M.

    1981-01-01

    The Dirac equation is solved with a linear and a quadratic scalar potential using an approach in which the Dirac equation is first transformed to a one-dimensional Schroedinger equation with an effective potential. The WKB method is used to obtain the energy eigenvalues. The eigenvalues for the quadratic scalar potential are real just as they are for the linear potential. The results with the linear potential agree well with those obtained by Critchfield. (author)

  1. A methodology framework for weighting genetic traits that impact greenhouse gas emission intensities in selection indexes.

    Science.gov (United States)

    Amer, P R; Hely, F S; Quinton, C D; Cromie, A R

    2018-01-01

    A methodological framework was presented for deriving weightings to be applied in selection indexes to account for the impact genetic change in traits will have on greenhouse gas emissions intensities (EIs). Although the emission component of the breeding goal was defined as the ratio of total emissions relative to a weighted combination of farm outputs, the resulting trait-weighting factors can be applied as linear weightings in a way that augments any existing breeding objective before consideration of EI. Calculus was used to define the parameters and assumptions required to link each trait change to the expected changes in EI for an animal production system. Four key components were identified. The potential impact of the trait on relative numbers of emitting animals per breeding female first has a direct effect on emission output but, second, also has a dilution effect from the extra output associated with the extra animals. Third, each genetic trait can potentially change the amount of emissions generated per animal and, finally, the potential impact of the trait on product output is accounted for. Emission intensity weightings derived from this equation require further modifications to integrate them into an existing breeding objective. These include accounting for different timing and frequency of trait expressions as well as a weighting factor to determine the degree of selection emphasis that is diverted away from improving farm profitability in order to achieve gains in EI. The methodology was demonstrated using a simple application to dairy cattle breeding in Ireland to quantify gains in EI reduction from existing genetic trends in milk production as well as in fertility and survival traits. Most gains were identified as coming through the dilution effect of genetic increases in milk protein per cow, although gains from genetic improvements in survival by reducing emissions from herd replacements were also significant. Emission intensities in the Irish

  2. Phenotypic correlations between egg weight and some egg quality ...

    African Journals Online (AJOL)

    Eggs were examined for both internal and external egg quality traits.Data obtained were subjected to one-way analysis of variance using the general linear procedure of SAS (2012). Differences in means were ranked using the Duncan's multiple Range test. Phenotypic correlations between egg weight and other egg quality ...

  3. Non-Weight-Bearing and Weight-Bearing Ultrasonography of Select Foot Muscles in Young, Asymptomatic Participants: A Descriptive and Reliability Study.

    Science.gov (United States)

    Battaglia, Patrick J; Mattox, Ross; Winchester, Brett; Kettner, Norman W

    The primary aim of this study was to determine the reliability of diagnostic ultrasound imaging for select intrinsic foot muscles using both non-weight-bearing and weight-bearing postures. Our secondary aim was to describe the change in muscle cross-sectional area (CSA) and dorsoplantar thickness when bearing weight. An ultrasound examination was performed with a linear ultrasound transducer operating between 9 and 12 MHz. Long-axis and short-axis ultrasound images of the abductor hallucis, flexor digitorum brevis, and quadratus plantae were obtained in both the non-weight-bearing and weight-bearing postures. Two examiners independently collected ultrasound images to allow for interexaminer and intraexaminer reliability calculation. The change in muscle CSA and dorsoplantar thickness when bearing weight was also studied. There were 26 participants (17 female) with a mean age of 25.5 ± 3.8 years and a mean body mass index of 28.0 ± 7.8 kg/m 2 . Inter-examiner reliability was excellent when measuring the muscles in short axis (intraclass correlation coefficient >0.75) and fair to good in long axis (intraclass correlation coefficient >0.4). Intraexaminer reliability was excellent for the abductor hallucis and flexor digitorum brevis and ranged from fair to good to excellent for the quadratus plantae. Bearing weight did not reduce interexaminer or intraexaminer reliability. All muscles exhibited a significant increase in CSA when bearing weight. This is the first report to describe weight-bearing diagnostic ultrasound of the intrinsic foot muscles. Ultrasound imaging is reliable when imaging these muscles bearing weight. Furthermore, muscle CSA increases in the weight-bearing posture. Copyright © 2016. Published by Elsevier Inc.

  4. Fetal growth in relation to gestational weight gain in women with Type 2 diabetes

    DEFF Research Database (Denmark)

    Parellada, C B; Asbjörnsdóttir, Björg; Ringholm, Lene

    2014-01-01

    AIMS: To evaluate fetal growth in relation to gestational weight gain in women with Type 2 diabetes. METHODS: A retrospective cohort study of 142 consecutive pregnancies in 28 women of normal weight, 39 overweight women and 75 obese women with Type 2 diabetes (pre-pregnancy BMI .../week, respectively. In multiple linear regression analysis, gestational weight gain was associated with a higher infant birth weight z-score independent of pre-pregnancy BMI, smoking, HbA1c and insulin dose at last visit, ethnicity and parity [β=0.1 (95% CI 0.06-0.14), P

  5. The International Linear Collider

    Directory of Open Access Journals (Sweden)

    List Benno

    2014-04-01

    Full Text Available The International Linear Collider (ILC is a proposed e+e− linear collider with a centre-of-mass energy of 200–500 GeV, based on superconducting RF cavities. The ILC would be an ideal machine for precision studies of a light Higgs boson and the top quark, and would have a discovery potential for new particles that is complementary to that of LHC. The clean experimental conditions would allow the operation of detectors with extremely good performance; two such detectors, ILD and SiD, are currently being designed. Both make use of novel concepts for tracking and calorimetry. The Japanese High Energy Physics community has recently recommended to build the ILC in Japan.

  6. The International Linear Collider

    Science.gov (United States)

    List, Benno

    2014-04-01

    The International Linear Collider (ILC) is a proposed e+e- linear collider with a centre-of-mass energy of 200-500 GeV, based on superconducting RF cavities. The ILC would be an ideal machine for precision studies of a light Higgs boson and the top quark, and would have a discovery potential for new particles that is complementary to that of LHC. The clean experimental conditions would allow the operation of detectors with extremely good performance; two such detectors, ILD and SiD, are currently being designed. Both make use of novel concepts for tracking and calorimetry. The Japanese High Energy Physics community has recently recommended to build the ILC in Japan.

  7. Reduction of Linear Programming to Linear Approximation

    OpenAIRE

    Vaserstein, Leonid N.

    2006-01-01

    It is well known that every Chebyshev linear approximation problem can be reduced to a linear program. In this paper we show that conversely every linear program can be reduced to a Chebyshev linear approximation problem.

  8. A counting-weighted calibration method for a field-programmable-gate-array-based time-to-digital converter

    International Nuclear Information System (INIS)

    Chen, Yuan-Ho

    2017-01-01

    In this work, we propose a counting-weighted calibration method for field-programmable-gate-array (FPGA)-based time-to-digital converter (TDC) to provide non-linearity calibration for use in positron emission tomography (PET) scanners. To deal with the non-linearity in FPGA, we developed a counting-weighted delay line (CWD) to count the delay time of the delay cells in the TDC in order to reduce the differential non-linearity (DNL) values based on code density counts. The performance of the proposed CWD-TDC with regard to linearity far exceeds that of TDC with a traditional tapped delay line (TDL) architecture, without the need for nonlinearity calibration. When implemented in a Xilinx Vertix-5 FPGA device, the proposed CWD-TDC achieved time resolution of 60 ps with integral non-linearity (INL) and DNL of [−0.54, 0.24] and [−0.66, 0.65] least-significant-bit (LSB), respectively. This is a clear indication of the suitability of the proposed FPGA-based CWD-TDC for use in PET scanners.

  9. A counting-weighted calibration method for a field-programmable-gate-array-based time-to-digital converter

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yuan-Ho, E-mail: chenyh@mail.cgu.edu.tw [Department of Electronic Engineering, Chang Gung University, Tao-Yuan 333, Taiwan (China); Department of Radiation Oncology, Chang Gung Memorial Hospital, Tao-Yuan 333, Taiwan (China); Center for Reliability Sciences and Technologies, Chang Gung University, Tao-Yuan 333, Taiwan (China)

    2017-05-11

    In this work, we propose a counting-weighted calibration method for field-programmable-gate-array (FPGA)-based time-to-digital converter (TDC) to provide non-linearity calibration for use in positron emission tomography (PET) scanners. To deal with the non-linearity in FPGA, we developed a counting-weighted delay line (CWD) to count the delay time of the delay cells in the TDC in order to reduce the differential non-linearity (DNL) values based on code density counts. The performance of the proposed CWD-TDC with regard to linearity far exceeds that of TDC with a traditional tapped delay line (TDL) architecture, without the need for nonlinearity calibration. When implemented in a Xilinx Vertix-5 FPGA device, the proposed CWD-TDC achieved time resolution of 60 ps with integral non-linearity (INL) and DNL of [−0.54, 0.24] and [−0.66, 0.65] least-significant-bit (LSB), respectively. This is a clear indication of the suitability of the proposed FPGA-based CWD-TDC for use in PET scanners.

  10. The potential association between fruit intake and body weight - a review

    DEFF Research Database (Denmark)

    Alinia, Sevil; Tetens, Inge; Hels, Ole

    2009-01-01

    intake reduced body weight, five of the prospective observational studies showed that fruit consumption reduced the risk of developing overweight and obesity, and four of the cross-sectional studies found an inverse association between fruit intake and body weight. Important methodological differences......Both national and international bodies recommend an increased intake of fruits and vegetables in order to decrease the risk of overweight and obesity. However, there is a rationale to investigate the separate role of fruits. The aim of this paper was to systematically review and analyse published...... and limitations in the studies make it difficult to compare results. However, the majority of the evidence points towards a possible inverse association between fruit intake and overweight. Future intervention and prospective observational studies examining the direct and independent role of fruit in body...

  11. Longitudinal impact of weight misperception and intent to change weight on body mass index of adolescents and young adults with overweight or obesity.

    Science.gov (United States)

    Rancourt, Diana; Thurston, Idia B; Sonneville, Kendrin R; Milliren, Carly E; Richmond, Tracy K

    2017-12-01

    Accurate perception of one's weight status is believed to be necessary to motivate weight loss intention and subsequent weight loss among those with overweight/obesity. This proposed pathway, however, is understudied in longitudinal research. This study examined the indirect effect of weight change intention on the relationship between weight status perception and BMI change among adolescents with overweight/obesity. Participants included 2664 adolescents with overweight/obesity (52% female) from the National Longitudinal Study of Adolescent Health. Longitudinal associations between Wave II weight status perception (accurate versus misperception) and intent to change weight (i.e., gain, lose, stay the same) on BMI change (Wave II-Wave IV) were examined using multiple linear regression. Indirect effects of weight change intention were investigated using the Monte Carlo method. Analyses were stratified by gender. Accurate perceivers (81.0% female; 60.1% male) were more likely than misperceivers (i.e., perception of "about the right weight") to report weight loss intention (p<0.001). Among females, weight status misperception and weight loss intention individually were associated with smaller (β=-1.37, 95% CI [-2.64, -0.10]) and greater (β=1.18, 95% CI [0.11, 2.25]) BMI gains, respectively. Among males, fully adjusted models suggested that weight status misperception was associated with significantly smaller gains in BMI over time (β=-1.51, 95% CI [-2.38, -0.63]). Weight change intention did not emerge as an indirect effect for either gender. Although weight status misperception was protective against weight gain, weight change intention did not provide an explanation for this relationship. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Direct and Maternal Additive Effects on Rabbit Growth and Linear ...

    African Journals Online (AJOL)

    Growth and linear body measurements of rabbits which consisted of 17 ew Zealand White (ZW), 19 Chinchilla (CH), 29 ZW x CH and 33 CH x ZW kittens were compared. The aim of the experiment was to evaluate the crossbreeding effects (i.e direct and maternal additive effect) for growth (individual body weight, IBW) and ...

  13. The inherent dynamics of a molecular liquid: Geodesic pathways through the potential energy landscape of a liquid of linear molecules

    Science.gov (United States)

    Jacobson, Daniel; Stratt, Richard M.

    2014-05-01

    Because the geodesic pathways that a liquid follows through its potential energy landscape govern its slow, diffusive motion, we suggest that these pathways are logical candidates for the title of a liquid's "inherent dynamics." Like their namesake "inherent structures," these objects are simply features of the system's potential energy surface and thus provide views of the system's structural evolution unobstructed by thermal kinetic energy. This paper shows how these geodesic pathways can be computed for a liquid of linear molecules, allowing us to see precisely how such molecular liquids mix rotational and translational degrees of freedom into their dynamics. The ratio of translational to rotational components of the geodesic path lengths, for example, is significantly larger than would be expected on equipartition grounds, with a value that scales with the molecular aspect ratio. These and other features of the geodesics are consistent with a picture in which molecular reorientation adiabatically follows translation—molecules largely thread their way through narrow channels available in the potential energy landscape.

  14. The effects of electronic cigarette emissions on systemic cotinine levels, weight and postnatal lung growth in neonatal mice.

    Directory of Open Access Journals (Sweden)

    Sharon A McGrath-Morrow

    Full Text Available Electronic cigarette (E-cigarettes emissions present a potentially new hazard to neonates through inhalation, dermal and oral contact. Exposure to nicotine containing E-cigarettes may cause significant systemic absorption in neonates due to the potential for multi-route exposure. Systemic absorption of nicotine and constituents of E-cigarette emissions may adversely impact weight and lung development in the neonate. To address these questions we exposed neonatal mice to E-cigarette emissions and measured systemic cotinine levels and alveolar lung growth.Neonatal mice were exposed to E-cigarettes for the first 10 days of life. E-cigarette cartridges contained either 1.8% nicotine in propylene glycol (PG or PG vehicle alone. Daily weights, plasma and urine cotinine levels and lung growth using the alveolar mean linear intercept (MLI method were measured at 10 days of life and compared to room air controls. Mice exposed to 1.8% nicotine/PG had a 13.3% decrease in total body weight compared to room air controls. Plasma cotinine levels were found to be elevated in neonatal mice exposed to 1.8% nicotine/PG E-cigarettes (mean 62.34± 3.3 ng/ml. After adjusting for sex and weight, the nicotine exposed mice were found to have modestly impaired lung growth by MLI compared to room air control mice (p<.054 trial 1; p<.006 trial 2. These studies indicate that exposure to E-cigarette emissions during the neonatal period can adversely impact weight gain. In addition exposure to nicotine containing E-cigarettes can cause detectable levels of systemic cotinine, diminished alveolar cell proliferation and a modest impairment in postnatal lung growth.

  15. On the solvability of Dirichlet problem for the weighted p-Laplacian

    Directory of Open Access Journals (Sweden)

    Ewa Szlachtowska

    2012-01-01

    Full Text Available The paper investigates the existence and uniqueness of weak solutions for a non-linear boundary value problem involving the weighted \\(p\\-Laplacian. Our approach is based on variational principles and representation properties of the associated spaces.

  16. Screening of transgenic proteins expressed in transgenic food crops for the presence of short amino acid sequences identical to potential, IgE – binding linear epitopes of allergens

    Directory of Open Access Journals (Sweden)

    Peijnenburg Ad ACM

    2002-12-01

    Full Text Available Abstract Background Transgenic proteins expressed by genetically modified food crops are evaluated for their potential allergenic properties prior to marketing, among others by identification of short identical amino acid sequences that occur both in the transgenic protein and allergenic proteins. A strategy is proposed, in which the positive outcomes of the sequence comparison with a minimal length of six amino acids are further screened for the presence of potential linear IgE-epitopes. This double track approach involves the use of literature data on IgE-epitopes and an antigenicity prediction algorithm. Results Thirty-three transgenic proteins have been screened for identities of at least six contiguous amino acids shared with allergenic proteins. Twenty-two transgenic proteins showed positive results of six- or seven-contiguous amino acids length. Only a limited number of identical stretches shared by transgenic proteins (papaya ringspot virus coat protein, acetolactate synthase GH50, and glyphosate oxidoreductase and allergenic proteins could be identified as (part of potential linear epitopes. Conclusion Many transgenic proteins have identical stretches of six or seven amino acids in common with allergenic proteins. Most identical stretches are likely to be false positives. As shown in this study, identical stretches can be further screened for relevance by comparison with linear IgE-binding epitopes described in literature. In the absence of literature data on epitopes, antigenicity prediction by computer aids to select potential antibody binding sites that will need verification of IgE binding by sera binding tests. Finally, the positive outcomes of this approach warrant further clinical testing for potential allergenicity.

  17. Post-mortem prediction of primal and selected retail cut weights of New Zealand lamb from carcass and animal characteristics.

    Science.gov (United States)

    Ngo, L; Ho, H; Hunter, P; Quinn, K; Thomson, A; Pearson, G

    2016-02-01

    Post-mortem measurements (cold weight, grade and external carcass linear dimensions) as well as live animal data (age, breed, sex) were used to predict ovine primal and retail cut weights for 792 lamb carcases. Significant levels of variance could be explained using these predictors. The predictive power of those measurements on primal and retail cut weights was studied by using the results from principal component analysis and the absolute value of the t-statistics of the linear regression model. High prediction accuracy for primal cut weight was achieved (adjusted R(2) up to 0.95), as well as moderate accuracy for key retail cut weight: tenderloins (adj-R(2)=0.60), loin (adj-R(2)=0.62), French rack (adj-R(2)=0.76) and rump (adj-R(2)=0.75). The carcass cold weight had the best predictive power, with the accuracy increasing by around 10% after including the next three most significant variables. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. MIDAS: Regionally linear multivariate discriminative statistical mapping.

    Science.gov (United States)

    Varol, Erdem; Sotiras, Aristeidis; Davatzikos, Christos

    2018-07-01

    Statistical parametric maps formed via voxel-wise mass-univariate tests, such as the general linear model, are commonly used to test hypotheses about regionally specific effects in neuroimaging cross-sectional studies where each subject is represented by a single image. Despite being informative, these techniques remain limited as they ignore multivariate relationships in the data. Most importantly, the commonly employed local Gaussian smoothing, which is important for accounting for registration errors and making the data follow Gaussian distributions, is usually chosen in an ad hoc fashion. Thus, it is often suboptimal for the task of detecting group differences and correlations with non-imaging variables. Information mapping techniques, such as searchlight, which use pattern classifiers to exploit multivariate information and obtain more powerful statistical maps, have become increasingly popular in recent years. However, existing methods may lead to important interpretation errors in practice (i.e., misidentifying a cluster as informative, or failing to detect truly informative voxels), while often being computationally expensive. To address these issues, we introduce a novel efficient multivariate statistical framework for cross-sectional studies, termed MIDAS, seeking highly sensitive and specific voxel-wise brain maps, while leveraging the power of regional discriminant analysis. In MIDAS, locally linear discriminative learning is applied to estimate the pattern that best discriminates between two groups, or predicts a variable of interest. This pattern is equivalent to local filtering by an optimal kernel whose coefficients are the weights of the linear discriminant. By composing information from all neighborhoods that contain a given voxel, MIDAS produces a statistic that collectively reflects the contribution of the voxel to the regional classifiers as well as the discriminative power of the classifiers. Critically, MIDAS efficiently assesses the

  19. Linear infrastructure impacts on landscape hydrology.

    Science.gov (United States)

    Raiter, Keren G; Prober, Suzanne M; Possingham, Hugh P; Westcott, Fiona; Hobbs, Richard J

    2018-01-15

    The extent of roads and other forms of linear infrastructure is burgeoning worldwide, but their impacts are inadequately understood and thus poorly mitigated. Previous studies have identified many potential impacts, including alterations to the hydrological functions and soil processes upon which ecosystems depend. However, these impacts have seldom been quantified at a regional level, particularly in arid and semi-arid systems where the gap in knowledge is the greatest, and impacts potentially the most severe. To explore the effects of extensive track, road, and rail networks on surface hydrology at a regional level we assessed over 1000 km of linear infrastructure, including approx. 300 locations where ephemeral streams crossed linear infrastructure, in the largely intact landscapes of Australia's Great Western Woodlands. We found a high level of association between linear infrastructure and altered surface hydrology, with erosion and pooling 5 and 6 times as likely to occur on-road than off-road on average (1.06 erosional and 0.69 pooling features km -1 on vehicle tracks, compared with 0.22 and 0.12 km -1 , off-road, respectively). Erosion severity was greater in the presence of tracks, and 98% of crossings of ephemeral streamlines showed some evidence of impact on water movement (flow impedance (62%); diversion of flows (73%); flow concentration (76%); and/or channel initiation (31%)). Infrastructure type, pastoral land use, culvert presence, soil clay content and erodibility, mean annual rainfall, rainfall erosivity, topography and bare soil cover influenced the frequency and severity of these impacts. We conclude that linear infrastructure frequently affects ephemeral stream flows and intercepts natural overland and near-surface flows, artificially changing site-scale moisture regimes, with some parts of the landscape becoming abnormally wet and other parts becoming water-starved. In addition, linear infrastructure frequently triggers or exacerbates erosion

  20. Thyroid Function and Body Weight: A Community-Based Longitudinal Study

    DEFF Research Database (Denmark)

    Bjergved, Lena; Jørgensen, Torben; Perrild, Hans

    2014-01-01

    . Weight increased by 0.3 kg (95% confidence interval [CI] 0.1, 0.4, P = 0.005) in women and 0.8 kg (95% CI 0.1, 1.4, P = 0.02) in men for every one unit TSH (mU/L) increase. Conclusions: TSH levels were not a determinant of future weight changes, and BMI was not a determinant for TSH changes......,102 individuals who participated at 11-year follow-up, without current or former treatment for thyroid disease and with measurements of TSH and weight at both examinations. Multiple linear regression models were used, stratified by sex and adjusted for age, smoking status, and leisure time physical activity....... Results: Baseline TSH concentration was not associated with change in weight (women, P = 0.17; men, P = 0.72), and baseline body mass index (BMI) was not associated with change in TSH (women, P = 0.21; men, P = 0.85). Change in serum TSH and change in weight were significantly associated in both sexes...

  1. Weighted least squares phase unwrapping based on the wavelet transform

    Science.gov (United States)

    Chen, Jiafeng; Chen, Haiqin; Yang, Zhengang; Ren, Haixia

    2007-01-01

    The weighted least squares phase unwrapping algorithm is a robust and accurate method to solve phase unwrapping problem. This method usually leads to a large sparse linear equation system. Gauss-Seidel relaxation iterative method is usually used to solve this large linear equation. However, this method is not practical due to its extremely slow convergence. The multigrid method is an efficient algorithm to improve convergence rate. However, this method needs an additional weight restriction operator which is very complicated. For this reason, the multiresolution analysis method based on the wavelet transform is proposed. By applying the wavelet transform, the original system is decomposed into its coarse and fine resolution levels and an equivalent equation system with better convergence condition can be obtained. Fast convergence in separate coarse resolution levels speeds up the overall system convergence rate. The simulated experiment shows that the proposed method converges faster and provides better result than the multigrid method.

  2. Preoperative computed tomography volumetry and graft weight estimation in adult living donor liver transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Pinheiro, Rafael S.; Cruz Junior, Ruy J.; Andraus, Wellington; Ducatti, Liliana; Martino, Rodrigo B.; Nacif, Lucas S.; Rocha-Santos, Vinicius; Arantes, Rubens M.; D' Albuquerque, Luiz A.C., E-mail: rsnpinheiro@gmail.com [Universidade de Sao Paulo (USP), SP (Brazil). Dept. de Gastroenterologia. Div. de Transplante de Orgaos do Aparelho Digestivo; Lai, Quirino [Universidade de L' Aquila, San Salvatore Hospital (Italy); Ibuki, Felicia S.; Rocha, Manoel S. [Universidade de Sao Paulo (USP), SP (Brazil). Departamento de Radiologia

    2017-09-01

    Background: Computed tomography volumetry (CTV) is a useful tool for predicting graft weights (GW) for living donor liver transplantation (LDLT). Few studies have examined the correlation between CTV and GW in normal liver parenchyma. Aim: To analyze the correlation between CTV and GW in an adult LDLT population and provide a systematic review of the existing mathematical models to calculate partial liver graft weight. Methods: Between January 2009 and January 2013, 28 consecutive donors undergoing right hepatectomy for LDLT were retrospectively reviewed. All grafts were perfused with HTK solution. Estimated graft volume was estimated by CTV and these values were compared to the actual graft weight, which was measured after liver harvesting and perfusion. Results: Median actual GW was 782.5 g, averaged 791.43±136 g and ranged from 520-1185 g. Median estimated graft volume was 927.5 ml, averaged 944.86±200.74 ml and ranged from 600-1477 ml. Linear regression of estimated graft volume and actual GW was significantly linear (GW=0.82 estimated graft volume, r{sup 2} =0.98, slope=0.47, standard deviation of 0.024 and p<0.0001). Spearman Linear correlation was 0.65 with 95% CI of 0.45 – 0.99 (p<0.0001). Conclusion: The one-to-one rule did not applied in patients with normal liver parenchyma. A better estimation of graft weight could be reached by multiplying estimated graft volume by 0.82. (author)

  3. Preoperative computed tomography volumetry and graft weight estimation in adult living donor liver transplantation

    International Nuclear Information System (INIS)

    Pinheiro, Rafael S.; Cruz Junior, Ruy J.; Andraus, Wellington; Ducatti, Liliana; Martino, Rodrigo B.; Nacif, Lucas S.; Rocha-Santos, Vinicius; Arantes, Rubens M.; D'Albuquerque, Luiz A.C.; Ibuki, Felicia S.; Rocha, Manoel S.

    2017-01-01

    Background: Computed tomography volumetry (CTV) is a useful tool for predicting graft weights (GW) for living donor liver transplantation (LDLT). Few studies have examined the correlation between CTV and GW in normal liver parenchyma. Aim: To analyze the correlation between CTV and GW in an adult LDLT population and provide a systematic review of the existing mathematical models to calculate partial liver graft weight. Methods: Between January 2009 and January 2013, 28 consecutive donors undergoing right hepatectomy for LDLT were retrospectively reviewed. All grafts were perfused with HTK solution. Estimated graft volume was estimated by CTV and these values were compared to the actual graft weight, which was measured after liver harvesting and perfusion. Results: Median actual GW was 782.5 g, averaged 791.43±136 g and ranged from 520-1185 g. Median estimated graft volume was 927.5 ml, averaged 944.86±200.74 ml and ranged from 600-1477 ml. Linear regression of estimated graft volume and actual GW was significantly linear (GW=0.82 estimated graft volume, r"2 =0.98, slope=0.47, standard deviation of 0.024 and p<0.0001). Spearman Linear correlation was 0.65 with 95% CI of 0.45 – 0.99 (p<0.0001). Conclusion: The one-to-one rule did not applied in patients with normal liver parenchyma. A better estimation of graft weight could be reached by multiplying estimated graft volume by 0.82. (author)

  4. PREOPERATIVE COMPUTED TOMOGRAPHY VOLUMETRY AND GRAFT WEIGHT ESTIMATION IN ADULT LIVING DONOR LIVER TRANSPLANTATION

    Science.gov (United States)

    PINHEIRO, Rafael S.; CRUZ-JR, Ruy J.; ANDRAUS, Wellington; DUCATTI, Liliana; MARTINO, Rodrigo B.; NACIF, Lucas S.; ROCHA-SANTOS, Vinicius; ARANTES, Rubens M; LAI, Quirino; IBUKI, Felicia S.; ROCHA, Manoel S.; D´ALBUQUERQUE, Luiz A. C.

    2017-01-01

    ABSTRACT Background: Computed tomography volumetry (CTV) is a useful tool for predicting graft weights (GW) for living donor liver transplantation (LDLT). Few studies have examined the correlation between CTV and GW in normal liver parenchyma. Aim: To analyze the correlation between CTV and GW in an adult LDLT population and provide a systematic review of the existing mathematical models to calculate partial liver graft weight. Methods: Between January 2009 and January 2013, 28 consecutive donors undergoing right hepatectomy for LDLT were retrospectively reviewed. All grafts were perfused with HTK solution. Estimated graft volume was estimated by CTV and these values were compared to the actual graft weight, which was measured after liver harvesting and perfusion. Results: Median actual GW was 782.5 g, averaged 791.43±136 g and ranged from 520-1185 g. Median estimated graft volume was 927.5 ml, averaged 944.86±200.74 ml and ranged from 600-1477 ml. Linear regression of estimated graft volume and actual GW was significantly linear (GW=0.82 estimated graft volume, r2=0.98, slope=0.47, standard deviation of 0.024 and p<0.0001). Spearman Linear correlation was 0.65 with 95% CI of 0.45 - 0.99 (p<0.0001). Conclusion: The one-to-one rule did not applied in patients with normal liver parenchyma. A better estimation of graft weight could be reached by multiplying estimated graft volume by 0.82. PMID:28489167

  5. A Bayesian posterior predictive framework for weighting ensemble regional climate models

    Directory of Open Access Journals (Sweden)

    Y. Fan

    2017-06-01

    Full Text Available We present a novel Bayesian statistical approach to computing model weights in climate change projection ensembles in order to create probabilistic projections. The weight of each climate model is obtained by weighting the current day observed data under the posterior distribution admitted under competing climate models. We use a linear model to describe the model output and observations. The approach accounts for uncertainty in model bias, trend and internal variability, including error in the observations used. Our framework is general, requires very little problem-specific input, and works well with default priors. We carry out cross-validation checks that confirm that the method produces the correct coverage.

  6. Comparison of equivalent linear and non linear methods on ground response analysis: case study at West Bangka site

    International Nuclear Information System (INIS)

    Eko Rudi Iswanto; Eric Yee

    2016-01-01

    Within the framework of identifying NPP sites, site surveys are performed in West Bangka (WB), Bangka-Belitung Island Province. Ground response analysis of a potential site has been carried out using peak strain profiles and peak ground acceleration. The objective of this research is to compare Equivalent Linear (EQL) and Non Linear (NL) methods of ground response analysis on the selected NPP site (West Bangka) using Deep Soil software. Equivalent linear method is widely used because requires soil data in simple way and short time of computational process. On the other hand, non linear method is capable of representing the actual soil behaviour by considering non linear soil parameter. The results showed that EQL method has similar trends to NL method. At surface layer, the acceleration values for EQL and NL methods are resulted as 0.425 g and 0.375 g respectively. NL method is more reliable in capturing higher frequencies of spectral acceleration compared to EQL method. (author)

  7. Variational linear algebraic equations method

    International Nuclear Information System (INIS)

    Moiseiwitsch, B.L.

    1982-01-01

    A modification of the linear algebraic equations method is described which ensures a variational bound on the phaseshifts for potentials having a definite sign at all points. The method is illustrated by the elastic scattering of s-wave electrons by the static field of atomic hydrogen. (author)

  8. Preliminary Study of Linear Density, Tenacity, and Crystallinity of Cotton Fibers

    Directory of Open Access Journals (Sweden)

    Yongliang Liu

    2014-07-01

    Full Text Available An investigation of the relationships among fiber linear density, tenacity, and structure is important to help cotton breeders modify varieties for enhanced fiber end-use qualities. This study employed the Stelometer instrument, which is the traditional fiber tenacity reference method and might still be an option as a rapid screening tool because of its low cost and portable attributes. In addition to flat bundle break force and weight variables from a routine Stelometer test, the number of fibers in the bundle were counted manually and the fiber crystallinity (CIIR was characterized by the previously proposed attenuated total reflection-sampling device based Fourier transform infrared (ATR-FTIR protocol. Based on the plots of either tenacity vs. linear density or fiber count vs. mass, the fibers were subjectively divided into fine or coarse sets, respectively. Relative to the distinctive increase in fiber tenacity with linear density, there was an unclear trend between the linear density and CIIR for these fibers. Samples with similar linear density were found to increase in tenacity with fiber CIIR. In general, Advanced Fiber Information System (AFIS fineness increases with fiber linear density.

  9. Changes in weight control behaviors and hedonic hunger during a 12-week commercial weight loss program.

    Science.gov (United States)

    O'Neil, Patrick M; Theim, Kelly R; Boeka, Abbe; Johnson, Gail; Miller-Kovach, Karen

    2012-12-01

    Greater use of key self-regulatory behaviors (e.g., self-monitoring of food intake and weight) is associated with greater weight loss within behavioral weight loss treatments, although this association is less established within widely-available commercial weight loss programs. Further, high hedonic hunger (i.e., susceptibility to environmental food cues) may present a barrier to successful behavior change and weight loss, although this has not yet been examined. Adult men and women (N=111, body mass index M±SD=31.5±2.7kg/m(2)) were assessed before and after participating in a 12-week commercial weight loss program. From pre- to post-treatment, reported usage of weight control behaviors improved and hedonic hunger decreased, and these changes were inversely associated. A decrease in hedonic hunger was associated with better weight loss. An improvement in reported weight control behaviors (e.g., self-regulatory behaviors) was associated with better weight loss, and this association was even stronger among individuals with high baseline hedonic hunger. Findings highlight the importance of specific self-regulatory behaviors within weight loss treatment, including a commercial weight loss program developed for widespread community implementation. Assessment of weight control behavioral skills usage and hedonic hunger may be useful to further identify mediators of weight loss within commercial weight loss programs. Future interventions might specifically target high hedonic hunger and prospectively examine changes in hedonic hunger during other types of weight loss treatment to inform its potential impact on sustained behavior change and weight control. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Association between blood cholesterol and sodium intake in hypertensive women with excess weight.

    Science.gov (United States)

    Padilha, Bruna Merten; Ferreira, Raphaela Costa; Bueno, Nassib Bezerra; Tassitano, Rafael Miranda; Holanda, Lidiana de Souza; Vasconcelos, Sandra Mary Lima; Cabral, Poliana Coelho

    2018-04-01

    Restricted sodium intake has been recommended for more than 1 century for the treatment of hypertension. However, restriction seems to increase blood cholesterol. In women with excess weight, blood cholesterol may increase even more because of insulin resistance and the high lipolytic activity of adipose tissue.The aim of this study was to assess the association between blood cholesterol and sodium intake in hypertensive women with and without excess weight.This was a cross-sectional study with hypertensive and nondiabetic women aged 20 to 59 years, recruited at the primary healthcare units of Maceio, Alagoas, Brazilian Northeast. Excess weight was defined as body mass index (BMI) ≥25.0 kg/m. Sodium intake was estimated by the 24-hour urinary excretion of sodium. Blood cholesterol was the primary outcome investigated by this study, and its relationship with sodium intake and other variables was assessed by Pearson correlation and multivariate linear regression using a significance level of 5%.This study included 165 hypertensive women. Of these, 135 (81.8%) were with excess weight. The mean sodium intake was 3.7 g (±1.9) and 3.4 g (±2.4) in hypertensive women with and without excess weight, respectively. The multiple normal linear regression models fitted to the "blood cholesterol" in the 2 groups reveal that for the group of hypertensive women without excess weight only 1 independent variable "age" is statistically significant to explain the variability of the blood cholesterol levels. However, for the group of hypertensive women with excess weight, 2 independent variables, age and sodium intake, can statistically explain variations of the blood cholesterol levels.Blood cholesterol is statistically inversely related to sodium intake for hypertensive women with excess weight, but it is not statistically related to sodium intake for hypertensive women without excess weight.

  11. Focused information criterion and model averaging based on weighted composite quantile regression

    KAUST Repository

    Xu, Ganggang; Wang, Suojin; Huang, Jianhua Z.

    2013-01-01

    We study the focused information criterion and frequentist model averaging and their application to post-model-selection inference for weighted composite quantile regression (WCQR) in the context of the additive partial linear models. With the non

  12. Reciprocating linear motor

    Science.gov (United States)

    Goldowsky, Michael P. (Inventor)

    1987-01-01

    A reciprocating linear motor is formed with a pair of ring-shaped permanent magnets having opposite radial polarizations, held axially apart by a nonmagnetic yoke, which serves as an axially displaceable armature assembly. A pair of annularly wound coils having axial lengths which differ from the axial lengths of the permanent magnets are serially coupled together in mutual opposition and positioned with an outer cylindrical core in axial symmetry about the armature assembly. One embodiment includes a second pair of annularly wound coils serially coupled together in mutual opposition and an inner cylindrical core positioned in axial symmetry inside the armature radially opposite to the first pair of coils. Application of a potential difference across a serial connection of the two pairs of coils creates a current flow perpendicular to the magnetic field created by the armature magnets, thereby causing limited linear displacement of the magnets relative to the coils.

  13. Linear reversible second-order cellular automata and their first-order matrix equivalents

    Science.gov (United States)

    Macfarlane, A. J.

    2004-11-01

    Linear or one-dimensional reversible second-order cellular automata, exemplified by three cases named as RCA1-3, are introduced. Displays of their evolution in discrete time steps, &{\\in}Z_2;) as for RCA1-3. MCA1-3 are tractable because it has been possible to generalize to them the heavy duty methods already well-developed for ordinary first-order cellular automata like those of Wolfram's Rules 90 and 150. While the automata MCA1-3 are thought to be of genuine interest in their own right, with untapped further mathematical potential, their treatment has been applied here to expediting derivation of a large body of general and explicit results for N(t) for RCA1-3. Amongst explicit results obtained are formulas also for each of RCA1-3 for the total weight of the configurations of the first &2^M; times, M =0, 1, 2,\\ldots.

  14. Adolescent Snacking Behaviors Are Associated with Dietary Intake and Weight Status123

    Science.gov (United States)

    Larson, Nicole I; Miller, Jonathan M; Watts, Allison W; Story, Mary T; Neumark-Sztainer, Dianne R

    2016-01-01

    Background: Most adolescents consume ≥1 snack/d; exploring the relevance of snacking patterns for overall diet and weight status is important to guide dietary counseling and public health strategies for obesity prevention. Objective: This study examined intake of common energy-dense snack foods, total number of snacks consumed, frequency of consuming snacks prepared away from home, and frequency of snacking while watching television in adolescents and how these behaviors may be linked to diet and weight status. Relations were examined with attention to potential confounders that may help explain the mixed findings of previous research. Methods: Survey measures of snacking behavior, a food-frequency questionnaire, and anthropometric measurements were completed by 2793 adolescents (53.2% girls, mean age = 14.4 y) in Minneapolis–St. Paul school classrooms in 2009–2010. Linear regression was used to examine associations with adjustment for sociodemographic characteristics and other potential confounding factors, such as meal skipping, underreporting energy intake, dieting to lose weight, and physical activity. Results: Adolescents reported consuming a mean of 2.2 energy-dense snack food servings/d and 4.3 snacks/d and purchasing snacks prepared away from home on 3.2 occasions/wk. More than two-thirds of adolescents reported that they sometimes, usually, or always consumed a snack while watching television. The measures of snacking were directly associated (P snack food servings were not related to sugar-sweetened beverage intake. A direct relation between daily servings of energy-dense snack foods and body mass index (BMI) z score was found; however, the snacking behaviors were inversely related to BMI z score (P snack consumption is a risk factor for poor diet, but unless energy-dense foods are consumed, snacking does not consistently contribute to overweight in US adolescents. PMID:27281807

  15. Estimated live weight of growing Pêga breed donkeys

    Directory of Open Access Journals (Sweden)

    Camilla Garcia Moreira

    2017-09-01

    Full Text Available ABSTRACT: The equations available in the literature to estimate the body weight (BW of Pêga breed donkeys were evaluated using 25 animals aged 0-6 months and it was proposed an equation for BW prediction. For the measurement of the thoracic perimeter (TP and for weighing the animals using the weighing tape, the animals were positioned in a forced station on a steep slope. An electronic scale was used for the determination of the BW. Accuracy of linear and nonlinear equations described in the literature was tested for BW prediction based on the animals’ TP, followed by the comparison of these equations with the equation developed in the present study for BW prediction of Pêga breed donkeys. A difference was noted (P<0.001 between the weights obtained on the electronic scale and the weighing tape. Linear and nonlinear equations available in the literature did not present favorable results with the data of the present study. The equation developed for the estimation of donkeys’ BW allowed the development of a weighing tape exclusive for young animals. Further evaluations are required for other Pêga donkey populations to confirm the efficacy of the proposed equation.

  16. Genetic relationships between carcass cut weights predicted from video image analysis and other performance traits in cattle.

    Science.gov (United States)

    Pabiou, T; Fikse, W F; Amer, P R; Cromie, A R; Näsholm, A; Berry, D P

    2012-09-01

    The objective of this study was to quantify the genetic associations between a range of carcass-related traits including wholesale cut weights predicted from video image analysis (VIA) technology, and a range of pre-slaughter performance traits in commercial Irish cattle. Predicted carcass cut weights comprised of cut weights based on retail value: lower value cuts (LVC), medium value cuts (MVC), high value cuts (HVC) and very high value cuts (VHVC), as well as total meat, fat and bone weights. Four main sources of data were used in the genetic analyses: price data of live animals collected from livestock auctions, live-weight data and linear type collected from both commercial and pedigree farms as well as from livestock auctions and weanling quality recorded on-farm. Heritability of carcass cut weights ranged from 0.21 to 0.39. Genetic correlations between the cut traits and the other performance traits were estimated using a series of bivariate sire linear mixed models where carcass cut weights were phenotypically adjusted to a constant carcass weight. Strongest positive genetic correlations were obtained between predicted carcass cut weights and carcass value (min r g(MVC) = 0.35; max r(g(VHVC)) = 0.69), and animal price at both weaning (min r(g(MVC)) = 0.37; max r(g(VHVC)) = 0.66) and post weaning (min r(g(MVC)) = 0.50; max r(g(VHVC)) = 0.67). Moderate genetic correlations were obtained between carcass cut weights and calf price (min r g(HVC) = 0.34; max r g(LVC) = 0.45), weanling quality (min r(g(MVC)) = 0.12; max r (g(VHVC)) = 0.49), linear scores for muscularity at both weaning (hindquarter development: min r(g(MVC)) = -0.06; max r(g(VHVC)) = 0.46), post weaning (hindquarter development: min r(g(MVC)) = 0.23; max r(g(VHVC)) = 0.44). The genetic correlations between total meat weight were consistent with those observed with the predicted wholesale cut weights. Total fat and total bone weights were generally negatively correlated with carcass value, auction

  17. Entropy-optimal weight constraint elicitation with additive multi-attribute utility models

    NARCIS (Netherlands)

    Valkenhoef , van Gert; Tervonen, Tommi

    2016-01-01

    We consider the elicitation of incomplete preference information for the additive utility model in terms of linear constraints on the weights. Eliciting incomplete preferences using holistic pair-wise judgments is convenient for the decision maker, but selecting the best pair-wise comparison is

  18. Statistical monitoring of linear antenna arrays

    KAUST Repository

    Harrou, Fouzi

    2016-11-03

    The paper concerns the problem of monitoring linear antenna arrays using the generalized likelihood ratio (GLR) test. When an abnormal event (fault) affects an array of antenna elements, the radiation pattern changes and significant deviation from the desired design performance specifications can resulted. In this paper, the detection of faults is addressed from a statistical point of view as a fault detection problem. Specifically, a statistical method rested on the GLR principle is used to detect potential faults in linear arrays. To assess the strength of the GLR-based monitoring scheme, three case studies involving different types of faults were performed. Simulation results clearly shown the effectiveness of the GLR-based fault-detection method to monitor the performance of linear antenna arrays.

  19. A novel weight determination method for time series data aggregation

    Science.gov (United States)

    Xu, Paiheng; Zhang, Rong; Deng, Yong

    2017-09-01

    Aggregation in time series is of great importance in time series smoothing, predicting and other time series analysis process, which makes it crucial to address the weights in times series correctly and reasonably. In this paper, a novel method to obtain the weights in time series is proposed, in which we adopt induced ordered weighted aggregation (IOWA) operator and visibility graph averaging (VGA) operator and linearly combine the weights separately generated by the two operator. The IOWA operator is introduced to the weight determination of time series, through which the time decay factor is taken into consideration. The VGA operator is able to generate weights with respect to the degree distribution in the visibility graph constructed from the corresponding time series, which reflects the relative importance of vertices in time series. The proposed method is applied to two practical datasets to illustrate its merits. The aggregation of Construction Cost Index (CCI) demonstrates the ability of proposed method to smooth time series, while the aggregation of The Taiwan Stock Exchange Capitalization Weighted Stock Index (TAIEX) illustrate how proposed method maintain the variation tendency of original data.

  20. Association Between Maternal Smoking During Pregnancy and Birth Weight: An Appropriately Adjusted Model From the Japan Environment and Children’s Study

    Science.gov (United States)

    Suzuki, Kohta; Shinohara, Ryoji; Sato, Miri; Otawa, Sanae; Yamagata, Zentaro

    2016-01-01

    Background There has been no large nationwide population-based study to examine the effects of maternal smoking status during pregnancy on birth weight that simultaneously controlled for clinical information, socioeconomic status, and maternal weight. Thus, this study aimed to determine the association between maternal smoking status during pregnancy and birth weight, while taking these confounding factors into consideration. Methods This study examined the first-year fixed dataset from a large nationwide birth cohort study that commenced in 2011. The dataset consisted of information on 9369 singleton infants born before December 31, 2011. Children were divided into 4 groups for statistical analysis: those born to mothers who did not smoke (NS), who quit smoking before pregnancy, who quit smoking during early pregnancy, and who smoked (SM). Multiple linear regression models were conducted for each sex to examine the association between maternal smoking status during early pregnancy and fetal growth. Birth weight was estimated using the least-squares method after controlling for covariates. Results After controlling for potential confounding factors, maternal smoking status during pregnancy was significantly associated with birth weight. There was a significant difference in birth weight between NS and SM for both male and female infants (male infants, 3096.2 g [NS] vs 2959.8 g [SM], P Japan, we have shown that maternal smoking during pregnancy may reduce birth weight by 125–136 g. PMID:26902166

  1. Particulate matter exposure during pregnancy is associated with birth weight, but not gestational age, 1962-1992: a cohort study

    Directory of Open Access Journals (Sweden)

    Pearce Mark S

    2012-03-01

    Full Text Available Abstract Background Exposure to air pollutants is suggested to adversely affect fetal growth, but the evidence remains inconsistent in relation to specific outcomes and exposure windows. Methods Using birth records from the two major maternity hospitals in Newcastle upon Tyne in northern England between 1961 and 1992, we constructed a database of all births to mothers resident within the city. Weekly black smoke exposure levels from routine data recorded at 20 air pollution monitoring stations were obtained and individual exposures were estimated via a two-stage modeling strategy, incorporating temporally and spatially varying covariates. Regression analyses, including 88,679 births, assessed potential associations between exposure to black smoke and birth weight, gestational age and birth weight standardized for gestational age and sex. Results Significant associations were seen between black smoke and both standardized and unstandardized birth weight, but not for gestational age when adjusted for potential confounders. Not all associations were linear. For an increase in whole pregnancy black smoke exposure, from the 1st (7.4 μg/m3 to the 25th (17.2 μg/m3, 50th (33.8 μg/m3, 75th (108.3 μg/m3, and 90th (180.8 μg/m3 percentiles, the adjusted estimated decreases in birth weight were 33 g (SE 1.05, 62 g (1.63, 98 g (2.26 and 109 g (2.44 respectively. A significant interaction was observed between socio-economic deprivation and black smoke on both standardized and unstandardized birth weight with increasing effects of black smoke in reducing birth weight seen with increasing socio-economic disadvantage. Conclusions The findings of this study progress the hypothesis that the association between black smoke and birth weight may be mediated through intrauterine growth restriction. The associations between black smoke and birth weight were of the same order of magnitude as those reported for passive smoking. These findings add to the growing

  2. Design of a linear neutron source

    International Nuclear Information System (INIS)

    Buzarbaruah, N.; Dutta, N.J.; Bhardwaz, J.K.; Mohanty, S.R.

    2015-01-01

    Highlights: • This paper reports the design of a linear neutron source based on inertial electrostatic confinement fusion scheme. • The voltage and current that is to be applied to the grid is computed theoretically. • Neutron production rate is theoretically estimated and found to be of the order of 10 7 –10 8 neutrons/s. • Electric potential distribution and ion trajectories are studied using SIMION code. • Optimized condition for the inner grid transparency has been found out. - Abstract: In this paper, we present the design of a linear neutron source based on the concept of inertial electrostatic confinement fusion. The source mainly comprises of a concentric coaxial cylindrical grid assembly housed inside a double walled cylindrical vacuum chamber, a gas injection system, a high voltage feedthrough and a high voltage negative polarity power supply. The inner grid will be kept at a high negative potential with respect to the outer grid that will be grounded. The effect of grid transparency on electric potential distribution and ion trajectories has been studied using SIMION. A diffuse deuterium plasma will be initially created by making filament discharge and subsequently, on application of high negative voltage to the inner grid, deuterons will be accelerated towards the axis of the device. These deuterons will oscillate in the negative potential and consequently fuse in between the grids to produce neutrons. This source is expected to produce 10 7 –10 8 neutrons/s. The proposed linear neutron source will be operated both in the continuous and pulse modes and it will be utilized for a few near term applications namely fusion reactor material studies and explosive detection

  3. Linear discriminant analysis of character sequences using occurrences of words

    KAUST Repository

    Dutta, Subhajit; Chaudhuri, Probal; Ghosh, Anil

    2014-01-01

    Classification of character sequences, where the characters come from a finite set, arises in disciplines such as molecular biology and computer science. For discriminant analysis of such character sequences, the Bayes classifier based on Markov models turns out to have class boundaries defined by linear functions of occurrences of words in the sequences. It is shown that for such classifiers based on Markov models with unknown orders, if the orders are estimated from the data using cross-validation, the resulting classifier has Bayes risk consistency under suitable conditions. Even when Markov models are not valid for the data, we develop methods for constructing classifiers based on linear functions of occurrences of words, where the word length is chosen by cross-validation. Such linear classifiers are constructed using ideas of support vector machines, regression depth, and distance weighted discrimination. We show that classifiers with linear class boundaries have certain optimal properties in terms of their asymptotic misclassification probabilities. The performance of these classifiers is demonstrated in various simulated and benchmark data sets.

  4. Linear discriminant analysis of character sequences using occurrences of words

    KAUST Repository

    Dutta, Subhajit

    2014-02-01

    Classification of character sequences, where the characters come from a finite set, arises in disciplines such as molecular biology and computer science. For discriminant analysis of such character sequences, the Bayes classifier based on Markov models turns out to have class boundaries defined by linear functions of occurrences of words in the sequences. It is shown that for such classifiers based on Markov models with unknown orders, if the orders are estimated from the data using cross-validation, the resulting classifier has Bayes risk consistency under suitable conditions. Even when Markov models are not valid for the data, we develop methods for constructing classifiers based on linear functions of occurrences of words, where the word length is chosen by cross-validation. Such linear classifiers are constructed using ideas of support vector machines, regression depth, and distance weighted discrimination. We show that classifiers with linear class boundaries have certain optimal properties in terms of their asymptotic misclassification probabilities. The performance of these classifiers is demonstrated in various simulated and benchmark data sets.

  5. Cross Coating Weight Control by Electromagnetic Strip Stabilization at the Continuous Galvanizing Line of ArcelorMittal Florange

    Science.gov (United States)

    Guelton, Nicolas; Lopès, Catherine; Sordini, Henri

    2016-08-01

    In hot dip galvanizing lines, strip bending around the sink roll generates a flatness defect called crossbow. This defect affects the cross coating weight distribution by changing the knife-to-strip distance along the strip width and requires a significant increase in coating target to prevent any risk of undercoating. The already-existing coating weight control system succeeds in eliminating both average and skew coating errors but cannot do anything against crossbow coating errors. It has therefore been upgraded with a flatness correction function which takes advantage of the possibility of controlling the electromagnetic stabilizer. The basic principle is to split, for every gage scan, the coating weight cross profile of the top and bottom sides into two, respectively, linear and non-linear components. The linear component is used to correct the skew error by realigning the knives with the strip, while the non-linear component is used to distort the strip in the stabilizer in such a way that the strip is kept flat between the knives. Industrial evaluation is currently in progress but the first results have already shown that the strip can be significantly flattened between the knives and the production tolerances subsequently tightened without compromising quality.

  6. Dextran: Influence of Molecular Weight in Antioxidant Properties and Immunomodulatory Potential.

    Science.gov (United States)

    Soeiro, Vinicius C; Melo, Karoline R T; Alves, Monique G C F; Medeiros, Mayara J C; Grilo, Maria L P M; Almeida-Lima, Jailma; Pontes, Daniel L; Costa, Leandro S; Rocha, Hugo A O

    2016-08-19

    Dextrans (α-d-glucans) extracted from Leuconostoc mesenteroides, with molecular weights (MW) of 10 (D10), 40 (D40) and 147 (D147) kDa, were evaluated as antioxidant, anticoagulant and immunomodulatory drugs for the first time. None presented anticoagulant activity. As for the antioxidant and immunomodulatory tests, a specific test showed an increase in the dextran activity that was proportional to the increase in molecular weight. In a different assay, however, activity decreased or showed no correlation to the MW. As an example, the reducing power assay showed that D147 was twice as potent as other dextrans. On the other hand, all three samples showed similar activity (50%) when it came to scavenging the OH radical, whereas only the D10 sample showed sharp activity (50%) when it came to scavenging the superoxide ion. D40 was the single dextran that presented with immunomodulatory features since it stimulated the proliferation (~50%) of murine macrophages (RAW 264.7) and decreased the release of nitric oxide (~40%) by the cells, both in the absence and presence of lipopolysaccharides (LPS). In addition, D40 showed a greater scavenging activity (50%) for the hydrogen peroxide, which caused it to also be the more potent dextran when it came to inhibiting lipid peroxidation (70%). These points toward dextrans with a 40 kDa weight as being ideal for antioxidant and immunomodulatory use. However, future studies with the D40 and other similarly 40 kDa dextrans are underway to confirm this hypothesis.

  7. Health risks, past usage, and intention to use weight loss products in normal weight women with high and low body dysphoria.

    Science.gov (United States)

    Whisenhunt, B L; Williamson, D A; Netemeyer, R G; Andrews, C

    2003-06-01

    There are many health risks involved with the use of weight loss products by normal weight women. The mass media may compound this problem through the promotion of weight loss products and a thin body size. This study tested women's perceptions of different weight loss product ads to determine if body dysphoria (i.e., an over concern with body size and shape in normal weight people) was associated with risk beliefs, past behaviors, and intention toward using weight loss products. Normal weight women (age range = 18-41 yr), who were classified as either high (n=45) or low (n=43) on a measure of body dysphoria, rated different weight loss products according to their perception of health risks, past behavior, and their intention to consume the products. These products were a dietary fat substitute (olestra), a prescription obesity medication (sibutramine), and an over-the-counter appetite suppressant (phenylpropanolamine). High body dysphoric women reported higher intentions to use the products as well as increased prior use of two of the three weight loss products. High body dysphoric women did not believe that these weight loss products were harmless. They recognized potential health risks associated with using such products, but nonetheless, expressed intention to use these weight loss products at a higher frequency. Also, several variables related to body image were found to effectively discriminate normal weight women at risk for abusing weight loss products. This study found that women who do not need to lose weight but have significant body image concerns were willing to use potentially harmful weight loss products despite the knowledge that such products might pose significant health risks. Techniques utilized by advertising regulatory agencies such as warning labels did not have a strong deterrent effect for stated intentions to use the products. Implications of these findings for public health policy issues were discussed.

  8. Van der Waals potentials between metal clusters and helium atoms obtained with density functional theory and linear response methods

    International Nuclear Information System (INIS)

    Liebrecht, M.

    2014-01-01

    The importance of van der Waals interactions in many diverse research fields such as, e. g., polymer science, nano--materials, structural biology, surface science and condensed matter physics created a high demand for efficient and accurate methods that can describe van der Waals interactions from first principles. These methods should be able to deal with large and complex systems to predict functions and properties of materials that are technologically and biologically relevant. Van der Waals interactions arise due to quantum mechanical correlation effects and finding appropriate models an numerical techniques to describe this type of interaction is still an ongoing challenge in electronic structure and condensed matter theory. This thesis introduces a new variational approach to obtain intermolecular interaction potentials between clusters and helium atoms by means of density functional theory and linear response methods. It scales almost linearly with the number of electrons and can therefore be applied to much larger systems than standard quantum chemistry techniques. The main focus of this work is the development of an ab-initio method to account for London dispersion forces, which are purely attractive and dominate the interaction of non--polar atoms and molecules at large distances. (author) [de

  9. Linear programming mathematics, theory and algorithms

    CERN Document Server

    1996-01-01

    Linear Programming provides an in-depth look at simplex based as well as the more recent interior point techniques for solving linear programming problems. Starting with a review of the mathematical underpinnings of these approaches, the text provides details of the primal and dual simplex methods with the primal-dual, composite, and steepest edge simplex algorithms. This then is followed by a discussion of interior point techniques, including projective and affine potential reduction, primal and dual affine scaling, and path following algorithms. Also covered is the theory and solution of the linear complementarity problem using both the complementary pivot algorithm and interior point routines. A feature of the book is its early and extensive development and use of duality theory. Audience: The book is written for students in the areas of mathematics, economics, engineering and management science, and professionals who need a sound foundation in the important and dynamic discipline of linear programming.

  10. The value of body weight measurement to assess dehydration in children.

    Science.gov (United States)

    Pruvost, Isabelle; Dubos, François; Chazard, Emmanuel; Hue, Valérie; Duhamel, Alain; Martinot, Alain

    2013-01-01

    Dehydration secondary to gastroenteritis is one of the most common reasons for office visits and hospital admissions. The indicator most commonly used to estimate dehydration status is acute weight loss. Post-illness weight gain is considered as the gold-standard to determine the true level of dehydration and is widely used to estimate weight loss in research. To determine the value of post-illness weight gain as a gold standard for acute dehydration, we conducted a prospective cohort study in which 293 children, aged 1 month to 2 years, with acute diarrhea were followed for 7 days during a 3-year period. The main outcome measures were an accurate pre-illness weight (if available within 8 days before the diarrhea), post-illness weight, and theoretical weight (predicted from the child's individual growth chart). Post-illness weight was measured for 231 (79%) and both theoretical and post-illness weights were obtained for 111 (39%). Only 62 (21%) had an accurate pre-illness weight. The correlation between post-illness and theoretical weight was excellent (0.978), but bootstrapped linear regression analysis showed that post-illness weight underestimated theoretical weight by 0.48 kg (95% CI: 0.06-0.79, pdehydration according to post-illness weight (21%) was significantly lower than the prevalence estimated by either theoretical weight (60%) or clinical assessment (66%, pdehydration. The performance of dehydration signs or scales determined by using post-illness weight as a gold standard has to be reconsidered.

  11. A tunable pH-sensing system based on Ag nanoclusters capped by hyperbranched polyethyleneimine with different molecular weights.

    Science.gov (United States)

    Qu, Fei; Zou, Xuan; Kong, Rongmei; You, Jinmao

    2016-01-01

    In this assay, a tunable pH sensing system was developed based on Ag nanoclusters (Ag NCs) capped by hyperbranched polyethyleneimine (PEI) with different molecular weights (abbreviated as Ag NC-PEIs). For instance, when the molecular weight of PEI was 600 or 1800, the fluorescence intensities of Ag NCs exhibited a linear fashion over the pH range 4.10-7.96; when the molecular weight of PEI was 25,000, the pH linear range was from 4.78 to 7.96; when the molecular weight of PEI was 70,000, the pH linear range was 6.09-8.95. According to the molecular weight of PEI 600/1800, 25,000, and 70,000, the color change point was pH 4.10-4.78, 5.33-6.09, and 6.09-6.80, respectively. Therefore, Ag NC-PEI 600 and 1800 were proper to acid conditions; Ag NC-PEI 25,000 was sensitive to weak acid media; while Ag NC-PEI 70,000 was adapted to neutral solution. The tunable and selective color change points brought an excellent feature of Ag NC-PEIs as visual pH indicators, which was flexible and applicable to a variety of environments. Besides, the ratios of absorbance at 415 nm and 268 nm of Ag NCs also showed linear relationships with pH variations. Therefore, there were three ways of this system for sensing pH values, including fluorescence assay, ultraviolet-visible measurement, and visual detection, suggesting that this tunable pH-sensing platform was more feasible, reliable, and accurate. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Photogeologic study of small-scale linear features near a potential nuclear-waste repository site at Yucca Mountain, southern Nye County, Nevada

    International Nuclear Information System (INIS)

    Throckmorton, C.K.

    1987-01-01

    Linear features were mapped from 1:2400-scale aerial photographs of the northern half of the potential underground nuclear-waste repository site at Yucca Mountain by means of a Kern PG 2 stereoplotter. These features were thought to be the expression of fractures at the ground surface (fracture traces), and were mapped in the caprock, upper lithophysal, undifferentiated lower lithophysal and hackly units of the Tiva Canyon Member of the Miocene Paintbrush Tuff. To determine if the linear features corresponded to fracture traces observed in the field, stations (areas) were selected on the map where the traces were both abundant and located solely within one unit. These areas were visited in the field, where fracture-trace bearings and fracture-trace lengths were recorded. Additional data on fracture-trace length and fracture abundance, obtained from ground-based studies of cleared pavements located within the study area were used to help evaluate data collected for this study. 16 refs., 4 figs., 2 tabs

  13. Linear Regression Based Real-Time Filtering

    Directory of Open Access Journals (Sweden)

    Misel Batmend

    2013-01-01

    Full Text Available This paper introduces real time filtering method based on linear least squares fitted line. Method can be used in case that a filtered signal is linear. This constraint narrows a band of potential applications. Advantage over Kalman filter is that it is computationally less expensive. The paper further deals with application of introduced method on filtering data used to evaluate a position of engraved material with respect to engraving machine. The filter was implemented to the CNC engraving machine control system. Experiments showing its performance are included.

  14. Low molecular weight salts combined with fluorinated solvents for electrolytes

    Science.gov (United States)

    Tikhonov, Konstantin; Yip, Ka Ki; Lin, Tzu-Yuan; Lei, Norman; Guerrero-Zavala, Guillermo; Kwong, Kristie W.

    2015-11-10

    Provided are electrochemical cells and electrolytes used to build such cells. An electrolyte includes at least one salt having a molecular weight less than about 250. Such salts allow forming electrolytes with higher salt concentrations and ensure high conductivity and ion transport in these electrolytes. The low molecular weight salt may have a concentration of at least about 0.5M and may be combined with one or more other salts, such as linear and cyclic imide salts and/or methide salts. The concentration of these additional salts may be less than that of the low molecular weight salt, in some embodiments, twice less. The additional salts may have a molecular weight greater than about 250. The electrolyte may also include one or more fluorinated solvents and may be capable of maintaining single phase solutions at between about -30.degree. C. to about 80.degree. C.

  15. The potential contribution of yellow cassava to dietary nutrient adequacy of primary-school children in Eastern Kenya; the use of linear programming

    OpenAIRE

    Talsma, Elise F.; Borgonjen-van den Berg, Karin J.; Melse-Boonstra, Alida; Mayer, Eva V.; Verhoef, Hans; Demir, Ayşe Y.; Ferguson, Elaine L.; Kok, Frans J.; Brouwer, Inge D.

    2018-01-01

    Objective: Introduction of biofortified cassava as school lunch can increase vitamin A intake, but may increase risk of other deficiencies due to poor nutrient profile of cassava. We assessed the potential effect of introducing a yellow cassava-based school lunch combined with additional food-based recommendations (FBR) on vitamin A and overall nutrient adequacy using Optifood (linear programming tool). Design: Cross-sectional study to assess dietary intakes (24 h recall) and derive model par...

  16. Polarized electronic sources for future e+/e- linear colliders

    International Nuclear Information System (INIS)

    Tang, H.; Alley, R.K.; Clendenin, J.E.

    1997-05-01

    Polarized electron beams will play a crucial role in maximizing the physics potential for future e + /e - linear colliders. We will review the SLC polarized electron source (PES), present a design for a conventional PES for the Next Linear Collider (NLC), and discuss the physics issues of a polarized RF gun

  17. Cross-sectional and Prospective Examination of Weight Misperception and Depressive Symptoms Among Youth with Overweight and Obesity.

    Science.gov (United States)

    Thurston, Idia B; Sonneville, Kendrin R; Milliren, Carly E; Kamody, Rebecca C; Gooding, Holly C; Richmond, Tracy K

    2017-02-01

    This study aims to determine the association between weight misperception (considering oneself average or underweight) and depressive symptoms among youth with overweight/obesity. Linear regression models (adjusted for age, BMI, parental education, percent poverty) were used to examine cross-sectional (wave II, 1996, n = 3898, M age  = 15.9, SD = 0.13) and longitudinal (from wave II to IV, 1996-2008/2009, n = 2738, M age  = 28.5, SD = 0.06) associations between weight misperception and depressive symptoms (Center for Epidemiologic Studies-Depression Scale) in a subsample of White, Black, Asian, Hispanic, and Multi-racial male and female youth with overweight/obesity participating in the National Longitudinal Study of Adolescent Health. Average BMI was 29.0 (0.16) at wave II and 35.7 (0.23) at wave IV. Thirty-two percent misperceived their weight status as average weight (n = 1151, 30 %) or underweight (n = 99, 3 %). In fully adjusted cross-sectional models, White (β = -1.92, 95 % CI = -2.79, -1.06) and Multi-racial (β = -4.43, 95 % CI = -6.90, -1.95) youth who perceived themselves as average weight had significantly lower depressive symptoms compared to accurate weight-perceivers. In fully adjusted longitudinal models, White youth (β = -0.41, 95 % CI = -0.81, -0.004) who perceived themselves as average weight had significantly lower depressive symptoms 12 years later. Findings suggest that weight misperception may be protective against depression among White adolescents and young adults with overweight/obesity. Clinical and population interventions should consider potential harmful effects of correcting weight misperceptions on the mental health of youth with overweight/obesity.

  18. Dynamic monitoring of weight data at the pen vs at the individual level

    DEFF Research Database (Denmark)

    Jensen, Dan; Toft, Nils; Kristensen, A. R. K.

    recorded weight data from finisher pigs. Data are collected at insertion and at the exit of the first pigs in the pen, and in few pens, the weight is recorded weekly. Dynamic linear models are fitted on the weight data, at the pig level (univariate), at the double pen level using averaged weight...... (univariate) and using individual pig values as parameters in a hierarchical (multivariate) model including section, double pen, and individual level. Variance components of the different models are estimated using the Expectation Maximization algorithm. The difference of information obtained...... at the individual vs pen level is thereafter assessed. Whereas weight data is usually monitored after a batch is being sent to the slaughter house, this method provides weekly updating of the data. Perspectives of application include dynamic monitoring of weight data in relation to events such as diarrhoea, tail...

  19. Dynamic monitoring of weight data at the pen vs at the individual level

    DEFF Research Database (Denmark)

    Jensen, Dan Børge; Toft, Nils; Kristensen, Anders Ringgaard

    recorded weight data from finisher pigs. Data are collected at insertion and at the exit of the first pigs in the pen, and in few pens, the weight is recorded weekly. Dynamic linear models are fitted on the weight data, at the pig level (univariate), at the double pen level using averaged weight...... (univariate) and using individual pig values as parameters in a hierarchical (multivariate) model including section, double pen, and individual level. Variance components of the different models are estimated using the Expectation Maximization algorithm. The difference of information obtained...... at the individual vs. pen level is thereafter assessed. Whereas weight data is usually monitored after a batch is being sent to the slaughter house, this method provides with weekly updating of the data. Perspectives of application include dynamic monitoring of weight data in relation to events such as diarrhoea...

  20. Linear Water Waves

    Science.gov (United States)

    Kuznetsov, N.; Maz'ya, V.; Vainberg, B.

    2002-08-01

    This book gives a self-contained and up-to-date account of mathematical results in the linear theory of water waves. The study of waves has many applications, including the prediction of behavior of floating bodies (ships, submarines, tension-leg platforms etc.), the calculation of wave-making resistance in naval architecture, and the description of wave patterns over bottom topography in geophysical hydrodynamics. The first section deals with time-harmonic waves. Three linear boundary value problems serve as the approximate mathematical models for these types of water waves. The next section uses a plethora of mathematical techniques in the investigation of these three problems. The techniques used in the book include integral equations based on Green's functions, various inequalities between the kinetic and potential energy and integral identities which are indispensable for proving the uniqueness theorems. The so-called inverse procedure is applied to constructing examples of non-uniqueness, usually referred to as 'trapped nodes.'

  1. Healthy Weight and Lifestyle Advertisements: An Assessment of Their Persuasive Potential

    Science.gov (United States)

    Dixon, Helen; Scully, Maree; Cotter, Trish; Maloney, Sarah; Wakefield, Melanie

    2015-01-01

    This study aimed to identify and analyse the content of previously produced and aired adult-targeted public health advertisements (ads) addressing weight, nutrition or physical activity internationally. Ads were identified via keyword searches of Google, YouTube and websites of relevant government agencies and health organizations, and were…

  2. Maternal weight change from prepregnancy to 7 years postpartum

    DEFF Research Database (Denmark)

    Kirkegaard, Helene; Stovring, Henrik; Rasmussen, Kathleen M

    2015-01-01

    OBJECTIVE: We studied the influence of maternal behavior on weight change from prepregnancy to 7 years postpartum. METHODS: We used linear regression to study the independent and combined associations between self-reported behavior in pregnancy (dietary intake, leisure-time exercise, sedentary...... activity, smoking) and postpartum (breastfeeding duration and smoking) on weights at 6 months, 18 months, and 7 years postpartum. RESULTS: Women's average 7-year weight gain was 2.07 kg, with 23% gaining >5 kg. Multivariable analyses suggested that women with healthier dietary intake, more leisure......-time exercise, less sedentary behavior, and longer duration of breastfeeding on average gained 1.66 kg [95% confidence interval (CI): 1.40; 1.91] with a significantly reduced odds [OR 0.56 (95% CI: 0.49; 0.64)] of gaining >5 kg from prepregnancy to 7 years postpartum compared to women with none or one...

  3. A first step toward uncovering the truth about weight tuning in deformable image registration

    Science.gov (United States)

    Pirpinia, Kleopatra; Bosman, Peter A. N.; Sonke, Jan-Jakob; van Herk, Marcel; Alderliesten, Tanja

    2016-03-01

    Deformable image registration is currently predominantly solved by optimizing a weighted linear combination of objectives. Successfully tuning the weights associated with these objectives is not trivial, leading to trial-and-error approaches. Such an approach assumes an intuitive interplay between weights, optimization objectives, and target registration errors. However, it is not known whether this always holds for existing registration methods. To investigate the interplay between weights, optimization objectives, and registration errors, we employ multi-objective optimization. Here, objectives of interest are optimized simultaneously, causing a set of multiple optimal solutions to exist, called the optimal Pareto front. Our medical application is in breast cancer and includes the challenging prone-supine registration problem. In total, we studied the interplay in three different ways. First, we ran many random linear combinations of objectives using the well-known registration software elastix. Second, since the optimization algorithms used in registration are typically of a local-search nature, final solutions may not always form a Pareto front. We therefore employed a multi-objective evolutionary algorithm that finds weights that correspond to registration outcomes that do form a Pareto front. Third, we examined how the interplay differs if a true multi-objective (i.e., weight-free) image registration method is used. Results indicate that a trial-and-error weight-adaptation approach can be successful for the easy prone to prone breast image registration case, due to the absence of many local optima. With increasing problem difficulty the use of more advanced approaches can be of value in finding and selecting the optimal registration outcomes.

  4. Linear growth patterns in small for gestational age and preterm infants after zinc supplementation

    Directory of Open Access Journals (Sweden)

    Caecilia Nancy Setiawan

    2015-03-01

    Full Text Available Background Low birth weight (LBW infants are at risk for growth disturbances due to intrauterine zinc deficiency. Zinc supplementation is expected to improve the linear growth of LBW babies. Objective To assess the effect of zinc supplementation on linear growth in preterm and small for gestational age (SGA infants. Methods This quasi-experimental study had a pre- and post-test design. Subjects were LBW infants hospitalized in Kariadi Hospital during March-December 2011, consisted of SGA and preterm neonates. All subjects were given 5 mg of zinc syrup daily for 3 months. Subjects’ head circumference, weight, and length were measured monthly. Serum zinc levels were measured before and after supplementation. Data were analyzed with Chi-square test, independent T-test, and general linear model repeated measure. Results A total of 61 subjects were enrolled consisted of 31 preterm and 30 SGA neonates. Mean serum zinc levels in the preterm group were 168.2 (SD 54.5 μg/dL pre-supplementation and 163.6 (SD 50.7 μg/dL post-supplementation (P=0.049, while mean serum zinc levels in the SGA group were 174.8 (SD 46.6 μg/dL pre-supplementation and 167.4 (SD 49.4 μg/dL post-supplementation (P=0.271. Median percentage preterm weight and length increased from 87.3 to 102.4% in the third month (P<0.001 and from 95.8 to 103.9% in the third month (P<0.001, respectively. Median percentage SGA weight and length increased from 73.5 to 98.3% in the third month (P<0.001 and from 94.5 to 102.2% in the third month (P<0.001, respectively. Conclusion Both, the preterm and SGA infants exhibit catch-up growth after three months of zinc supplementation. [

  5. Gene selection for the reconstruction of stem cell differentiation trees: a linear programming approach.

    Science.gov (United States)

    Ghadie, Mohamed A; Japkowicz, Nathalie; Perkins, Theodore J

    2015-08-15

    Stem cell differentiation is largely guided by master transcriptional regulators, but it also depends on the expression of other types of genes, such as cell cycle genes, signaling genes, metabolic genes, trafficking genes, etc. Traditional approaches to understanding gene expression patterns across multiple conditions, such as principal components analysis or K-means clustering, can group cell types based on gene expression, but they do so without knowledge of the differentiation hierarchy. Hierarchical clustering can organize cell types into a tree, but in general this tree is different from the differentiation hierarchy itself. Given the differentiation hierarchy and gene expression data at each node, we construct a weighted Euclidean distance metric such that the minimum spanning tree with respect to that metric is precisely the given differentiation hierarchy. We provide a set of linear constraints that are provably sufficient for the desired construction and a linear programming approach to identify sparse sets of weights, effectively identifying genes that are most relevant for discriminating different parts of the tree. We apply our method to microarray gene expression data describing 38 cell types in the hematopoiesis hierarchy, constructing a weighted Euclidean metric that uses just 175 genes. However, we find that there are many alternative sets of weights that satisfy the linear constraints. Thus, in the style of random-forest training, we also construct metrics based on random subsets of the genes and compare them to the metric of 175 genes. We then report on the selected genes and their biological functions. Our approach offers a new way to identify genes that may have important roles in stem cell differentiation. tperkins@ohri.ca Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  6. Development of standard weight equations for Caribbean and Gulf of Mexico amphidromous fishes

    Science.gov (United States)

    Cooney, Patrick B.; Kwak, Thomas J.

    2010-01-01

    We collected and compiled length and weight information from four countries and one commonwealth to develop standard weight (Ws) equations for three amphidromous fish species native to the Caribbean and Gulf of Mexico regions: mountain mullet Agonostomus monticola (N = 9,768 individuals, 52 populations), river goby Awaous banana (N = 1,847 individuals, 62 populations), and bigmouth sleeper Gobiomorus dormitor (N = 2,983 individuals, 53 populations). Linear and quadratic Ws equations for three quartiles (25%, median, 75%) are presented for these three species. The length-weight relationship from eight lentic bigmouth sleeper populations was significantly different from that of lotic populations, reflecting higher weights of juvenile fish (sport fisheries and allow ecological assessment based on fish condition.

  7. Stability analysis of switched linear systems defined by graphs

    OpenAIRE

    Athanasopoulos, Nikolaos; Lazar, Mircea

    2015-01-01

    We present necessary and sufficient conditions for global exponential stability for switched discrete-time linear systems, under arbitrary switching, which is constrained within a set of admissible transitions. The class of systems studied includes the family of systems under arbitrary switching, periodic systems, and systems with minimum and maximum dwell time specifications. To reach the result, we describe the set of rules that define the admissible transitions with a weighted directed gra...

  8. Ischemic Colitis after Weight-Loss Medication

    Directory of Open Access Journals (Sweden)

    Dan Comay

    2003-01-01

    Full Text Available BACKGROUND: Previous weight-loss medications have received cautious support due to their association with pulmonary hypertension and valvular heart disease. However, newer drugs are increasingly being recommended as potentially safer and more efficacious. We report a case of ischemic colitis possibly linked to the use of a weight-loss drug, and review the literature to highlight an important latent consequence of these medications.

  9. Predicting risk of substantial weight gain in German adults-a multi-center cohort approach.

    Science.gov (United States)

    Bachlechner, Ursula; Boeing, Heiner; Haftenberger, Marjolein; Schienkiewitz, Anja; Scheidt-Nave, Christa; Vogt, Susanne; Thorand, Barbara; Peters, Annette; Schipf, Sabine; Ittermann, Till; Völzke, Henry; Nöthlings, Ute; Neamat-Allah, Jasmine; Greiser, Karin-Halina; Kaaks, Rudolf; Steffen, Annika

    2017-08-01

    A risk-targeted prevention strategy may efficiently utilize limited resources available for prevention of overweight and obesity. Likewise, more efficient intervention trials could be designed if selection of subjects was based on risk. The aim of the study was to develop a risk score predicting substantial weight gain among German adults. We developed the risk score using information on 15 socio-demographic, dietary and lifestyle factors from 32 204 participants of five population-based German cohort studies. Substantial weight gain was defined as gaining ≥10% of weight between baseline and follow-up (>6 years apart). The cases were censored according to the theoretical point in time when the threshold of 10% baseline-based weight gain was crossed assuming linearity of weight gain. Beta coefficients derived from proportional hazards regression were used as weights to compute the risk score as a linear combination of the predictors. Cross-validation was used to evaluate the score's discriminatory accuracy. The cross-validated c index (95% CI) was 0.71 (0.67-0.75). A cutoff value of ≥475 score points yielded a sensitivity of 71% and a specificity of 63%. The corresponding positive and negative predictive values were 10.4% and 97.6%, respectively. The proposed risk score may support healthcare providers in decision making and referral and facilitate an efficient selection of subjects into intervention trials. © The Author 2016. Published by Oxford University Press on behalf of the European Public Health Association.

  10. Predicting risk of substantial weight gain in German adults—a multi-center cohort approach

    Science.gov (United States)

    Bachlechner, Ursula; Boeing, Heiner; Haftenberger, Marjolein; Schienkiewitz, Anja; Scheidt-Nave, Christa; Vogt, Susanne; Thorand, Barbara; Peters, Annette; Schipf, Sabine; Ittermann, Till; Völzke, Henry; Nöthlings, Ute; Neamat-Allah, Jasmine; Greiser, Karin-Halina; Kaaks, Rudolf

    2017-01-01

    Abstract Background A risk-targeted prevention strategy may efficiently utilize limited resources available for prevention of overweight and obesity. Likewise, more efficient intervention trials could be designed if selection of subjects was based on risk. The aim of the study was to develop a risk score predicting substantial weight gain among German adults. Methods We developed the risk score using information on 15 socio-demographic, dietary and lifestyle factors from 32 204 participants of five population-based German cohort studies. Substantial weight gain was defined as gaining ≥10% of weight between baseline and follow-up (>6 years apart). The cases were censored according to the theoretical point in time when the threshold of 10% baseline-based weight gain was crossed assuming linearity of weight gain. Beta coefficients derived from proportional hazards regression were used as weights to compute the risk score as a linear combination of the predictors. Cross-validation was used to evaluate the score’s discriminatory accuracy. Results The cross-validated c index (95% CI) was 0.71 (0.67–0.75). A cutoff value of ≥475 score points yielded a sensitivity of 71% and a specificity of 63%. The corresponding positive and negative predictive values were 10.4% and 97.6%, respectively. Conclusions The proposed risk score may support healthcare providers in decision making and referral and facilitate an efficient selection of subjects into intervention trials. PMID:28013243

  11. Analytic evaluation of the weighting functions for remote sensing of blackbody planetary atmospheres : the case of limb viewing geometry

    Science.gov (United States)

    Ustinov, Eugene A.

    2006-01-01

    In a recent publication (Ustinov, 2002), we proposed an analytic approach to evaluation of radiative and geophysical weighting functions for remote sensing of a blackbody planetary atmosphere, based on general linearization approach applied to the case of nadir viewing geometry. In this presentation, the general linearization approach is applied to the limb viewing geometry. The expressions, similar to those obtained in (Ustinov, 2002), are obtained for weighting functions with respect to the distance along the line of sight. Further on, these expressions are converted to the expressions for weighting functions with respect to the vertical coordinate in the atmosphere. Finally, the numerical representation of weighting functions in the form of matrices of partial derivatives of grid limb radiances with respect to the grid values of atmospheric parameters is used for a convolution with the finite field of view of the instrument.

  12. SEARCHING FOR LOW WEIGHT PSEUDO-CODEWORDS

    International Nuclear Information System (INIS)

    Chertkov, Michael; Stepanov, Mikhail

    2007-01-01

    Belief Propagation (BP) and Linear Programming (LP) decodings of LDPC codes are discussed. The authors summarize results of instanton/pseudo-codeword approach developed for analysis of the error-floor domain of the codes. Instantons are special, code and decoding specific, configurations of the channel noise contributing most to the Frame-Error-Rate (FER). Instantons are decoded into pseudo-codewords. Instanton/pseudo-codeword with the lowest weight describes the largest Signal-to-Noise-Ratio (SNR) asymptotic of FER, while the whole spectra of the low weight instantons is descriptive of the FER vs. SNR profile in the extended error-floor domain. First, they describe a general optimization method that allows to find the instantons for any coding/decoding. Second, they introduce LP-specific pseudo-codeword search algorithm that allows efficient calculations of the pseudo-codeword spectra. Finally, they discuss results of combined BP/LP error-floor exploration experiments for two mode codes.

  13. SEARCHING FOR LOW WEIGHT PSEUDO-CODEWORDS

    Energy Technology Data Exchange (ETDEWEB)

    CHERTKOV, MICHAEL [Los Alamos National Laboratory; STEPANOV, MIKHAIL [Los Alamos National Laboratory

    2007-01-23

    Belief Propagation (BP) and Linear Programming (LP) decodings of LDPC codes are discussed. The authors summarize results of instanton/pseudo-codeword approach developed for analysis of the error-floor domain of the codes. Instantons are special, code and decoding specific, configurations of the channel noise contributing most to the Frame-Error-Rate (FER). Instantons are decoded into pseudo-codewords. Instanton/pseudo-codeword with the lowest weight describes the largest Signal-to-Noise-Ratio (SNR) asymptotic of FER, while the whole spectra of the low weight instantons is descriptive of the FER vs. SNR profile in the extended error-floor domain. First, they describe a general optimization method that allows to find the instantons for any coding/decoding. Second, they introduce LP-specific pseudo-codeword search algorithm that allows efficient calculations of the pseudo-codeword spectra. Finally, they discuss results of combined BP/LP error-floor exploration experiments for two mode codes.

  14. Linear versus non-linear supersymmetry, in general

    Energy Technology Data Exchange (ETDEWEB)

    Ferrara, Sergio [Theoretical Physics Department, CERN,CH-1211 Geneva 23 (Switzerland); INFN - Laboratori Nazionali di Frascati,Via Enrico Fermi 40, I-00044 Frascati (Italy); Department of Physics and Astronomy, UniversityC.L.A.,Los Angeles, CA 90095-1547 (United States); Kallosh, Renata [SITP and Department of Physics, Stanford University,Stanford, California 94305 (United States); Proeyen, Antoine Van [Institute for Theoretical Physics, Katholieke Universiteit Leuven,Celestijnenlaan 200D, B-3001 Leuven (Belgium); Wrase, Timm [Institute for Theoretical Physics, Technische Universität Wien,Wiedner Hauptstr. 8-10, A-1040 Vienna (Austria)

    2016-04-12

    We study superconformal and supergravity models with constrained superfields. The underlying version of such models with all unconstrained superfields and linearly realized supersymmetry is presented here, in addition to the physical multiplets there are Lagrange multiplier (LM) superfields. Once the equations of motion for the LM superfields are solved, some of the physical superfields become constrained. The linear supersymmetry of the original models becomes non-linearly realized, its exact form can be deduced from the original linear supersymmetry. Known examples of constrained superfields are shown to require the following LM’s: chiral superfields, linear superfields, general complex superfields, some of them are multiplets with a spin.

  15. Linear versus non-linear supersymmetry, in general

    International Nuclear Information System (INIS)

    Ferrara, Sergio; Kallosh, Renata; Proeyen, Antoine Van; Wrase, Timm

    2016-01-01

    We study superconformal and supergravity models with constrained superfields. The underlying version of such models with all unconstrained superfields and linearly realized supersymmetry is presented here, in addition to the physical multiplets there are Lagrange multiplier (LM) superfields. Once the equations of motion for the LM superfields are solved, some of the physical superfields become constrained. The linear supersymmetry of the original models becomes non-linearly realized, its exact form can be deduced from the original linear supersymmetry. Known examples of constrained superfields are shown to require the following LM’s: chiral superfields, linear superfields, general complex superfields, some of them are multiplets with a spin.

  16. A perfect storm: examining the synergistic effects of negative and positive emotional instability on promoting weight loss activities in anorexia nervosa

    Science.gov (United States)

    Selby, Edward A.; Cornelius, Talea; Fehling, Kara B.; Kranzler, Amy; Panza, Emily A.; Lavender, Jason M.; Wonderlich, Stephen A.; Crosby, Ross D.; Engel, Scott G.; Mitchell, James E.; Crow, Scott J.; Peterson, Carol B.; Grange, Daniel Le

    2015-01-01

    Growing evidence indicates that both positive and negative emotion potentially influence the development and maintenance of anorexia nervosa, through both positive and negative reinforcement of weight loss activities. Such reactive emotional experience may be characterized by frequent and intense fluctuations in emotion, a construct known as “emotional instability.” The purpose of this study was to investigate the association between positive emotional instability and weight loss activities in anorexia nervosa, and to investigate the synergistic effects of positive and negative emotional instability on promoting weight loss activities. Using ecological momentary assessment methods, 118 participants with anorexia nervosa reported their emotional experiences and behaviors at least six times daily over 2 weeks using a portable digital device. Using generalized linear modeling, results indicated that high levels of both positive and negative emotional instability, and the interaction between the two, were associated with more frequent weight-loss activities, beyond anorexia subtype and mean levels of emotional intensity. These findings indicate that when women with anorexia exhibit both high levels of both positive and negative emotional instability they are more prone to a variety of weight loss activities. The importance of addressing the role of both positive and negative emotion in anorexia treatment is discussed. PMID:26379588

  17. Stochastic equivalent linearization in 3-D hysteretic frames

    International Nuclear Information System (INIS)

    Casciati, F.; Faravelli, L.

    1987-01-01

    Stochastic equivalent linearization technique for hysteretic systems is extended to study the dynamic response of 3-D frames with hysteretic constitutive laws in the potential plastic hinges. The constitutive law is idealized by an appropriate endochronic model. A general purpose finite element code is adopted in order to generate the matrices by which the equations of motion to be linearized are built. (orig./HP)

  18. Gestational Weight Gain and Pregnancy Outcomes in 481 Obese Glucose-Tolerant Women

    DEFF Research Database (Denmark)

    Jensen, Dorte Møller; Ovesen, Per; Beck-Nielsen, Henning

    2005-01-01

    OBJECTIVE: To investigate the effect of gestational weight gain in obese glucose-tolerant women. RESEARCH DESIGN AND METHODS: We performed a historical cohort study of 481 women with prepregnancy BMI > or = 30 kg/m2 and a normal 2-h 75-g oral glucose tolerance test (OGTT) during the third trimester......-weight women (3,478 g). In multivariate analyses, increasing weight gain was associated with significantly higher rates of hypertension (OR 4.8 [95% CI for group 4 vs. group 1: 1.7-13.1]), cesarean section (3.5 [1.6-7.8]), induction of labor (3.7 [1.7-8.0]), and large-for-gestational-age infants (4.7 [2.......0-11.0]). There was no difference in rates of small-for-gestational-age infants. Significant predictors for birth weight (determined by multiple linear regression) were gestational weight gain, 2-h OGTT result, pre-gestational BMI, maternal age, gestational age, and smoking. CONCLUSIONS: Increasing weight gain in obese women...

  19. A geographically weighted regression model for geothermal potential assessment in mediterranean cultural landscape

    Science.gov (United States)

    D'Arpa, S.; Zaccarelli, N.; Bruno, D. E.; Leucci, G.; Uricchio, V. F.; Zurlini, G.

    2012-04-01

    Geothermal heat can be used directly in many applications (agro-industrial processes, sanitary hot water production, heating/cooling systems, etc.). These applications respond to energetic and environmental sustainability criteria, ensuring substantial energy savings with low environmental impacts. In particular, in Mediterranean cultural landscapes the exploitation of geothermal energy offers a valuable alternative compared to other exploitation systems more land-consuming and visual-impact. However, low enthalpy geothermal energy applications at regional scale, require careful design and planning to fully exploit benefits and reduce drawbacks. We propose a first example of application of a Geographically Weighted Regression (GWR) for the modeling of geothermal potential in the Apulia Region (South Italy) by integrating hydrological (e.g. depth to water table, water speed and temperature), geological-geotechnical (e.g. lithology, thermal conductivity) parameters and land-use indicators. The GWR model can effectively cope with data quality, spatial anisotropy, lack of stationarity and presence of discontinuities in the underlying data maps. The geothermal potential assessment required a good knowledge of the space-time variation of the numerous parameters related to the status of geothermal resource, a contextual analysis of spatial and environmental features, as well as the presence and nature of regulations or infrastructures constraints. We create an ad hoc geodatabase within ArcGIS 10 collecting relevant data and performing a quality assessment. Cross-validation shows high level of consistency of the spatial local models, as well as error maps can depict areas of lower reliability. Based on low enthalpy geothermal potential map created, a first zoning of the study area is proposed, considering four level of possible exploitation. Such zoning is linked and refined by the actual legal constraints acting at regional or province level as enforced by the regional

  20. Perfluoroalkyl Substances during Pregnancy and Offspring Weight and Adiposity at Birth: Examining Mediation by Maternal Fasting Glucose in the Healthy Start Study.

    Science.gov (United States)

    Starling, Anne P; Adgate, John L; Hamman, Richard F; Kechris, Katerina; Calafat, Antonia M; Ye, Xiaoyun; Dabelea, Dana

    2017-06-26

    Certain perfluoroalkyl and polyfluoroalkyl substances (PFAS) are widespread, persistent environmental contaminants. Prenatal PFAS exposure has been associated with lower birth weight; however, impacts on body composition and factors responsible for this association are unknown. We aimed to estimate associations between maternal PFAS concentrations and offspring weight and adiposity at birth, and secondarily to estimate associations between PFAS concentrations and maternal glucose and lipids, and to evaluate the potential for these nutrients to mediate associations between PFAS and neonatal outcomes. Within the Healthy Start prospective cohort, concentrations of 11 PFAS, fasting glucose, and lipids were measured in maternal mid-pregnancy serum (n=628). Infant body composition was measured using air displacement plethysmography. Associations between PFAS and birth weight and adiposity, and between PFAS and maternal glucose and lipids, were estimated via linear regression. Associations were decomposed into direct and indirect effects. Five PFAS were detectable in >50% of participants. Maternal perfluorooctanoate (PFOA) and perfluorononanoate (PFNA) concentrations were inversely associated with birth weight. Adiposity at birth was approximately 10% lower in the highest categories of PFOA, PFNA, and perfluorohexane sulfonate (PFHxS) compared to the lowest categories. PFOA, PFNA, perfluorodecanoate (PFDeA), and PFHxS were inversely associated with maternal glucose. Up to 11.6% of the effect of PFAS on neonatal adiposity was mediated by maternal glucose concentrations. Perfluorooctane sulfonate (PFOS) was not significantly associated with any outcomes studied. Follow-up of offspring will determine the potential long-term consequences of lower weight and adiposity at birth associated with prenatal PFAS exposure. https://doi.org/10.1289/EHP641.

  1. Ameliorative potentials of cocoyam (Colocasia esculenta L.) and unripe plantain (Musa paradisiaca L.) on the relative tissue weights of streptozotocin-induced diabetic rats.

    Science.gov (United States)

    Eleazu, C O; Iroaganachi, M; Eleazu, K C

    2013-01-01

    To investigate the ameliorating potentials of cocoyam (Colocasia esculenta L.) and unripe plantain (Musa paradisiaca L.) incorporated feeds on the renal and liver growths of diabetic rats, induced with 55 and 65 mg/kg body weight of Streptozotocin. The blood glucose level of the rats was measured with a glucometer, the protein and glucose and specific gravity (SPGR) in the urine samples of the rats were measured using urine assay strips and urinometer respectively. The chemical composition and antioxidant screening of the test feeds were carried out using standard techniques. Administration of the test feeds for 21 days to the diabetic rats of groups 4 and 5, resulted in 58.75% and 38.13% decreases in hyperglycemia and amelioration of their elevated urinary protein, glucose, SPGR, and relative kidney weights. The diabetic rats administered cocoyam incorporated feeds, had 2.71% and 19.52% increases in weight and growth rates, the diabetic rats administered unripe plantain incorporated feeds had 5.12% and 29.52% decreases in weight and growth rates while the diabetic control rats had 28.69%, 29.46%, 248.9% and 250.14% decreases in weights and growth rates. The cocoyam incorporated feeds contained higher antioxidants, minerals and phytochemicals except alkaloids than unripe plantain feed. Cocoyam and unripe plantain could be useful in the management of diabetic nephropathy.

  2. Ameliorative Potentials of Cocoyam (Colocasia esculenta L. and Unripe Plantain (Musa paradisiaca L. on the Relative Tissue Weights of Streptozotocin-Induced Diabetic Rats

    Directory of Open Access Journals (Sweden)

    C. O. Eleazu

    2013-01-01

    Full Text Available Aim. To investigate the ameliorating potentials of cocoyam (Colocasia esculenta L. and unripe plantain (Musa paradisiaca L. incorporated feeds on the renal and liver growths of diabetic rats, induced with 55 and 65 mg/kg body weight of Streptozotocin. Method. The blood glucose level of the rats was measured with a glucometer, the protein and glucose and specific gravity (SPGR in the urine samples of the rats were measured using urine assay strips and urinometer respectively. The chemical composition and antioxidant screening of the test feeds were carried out using standard techniques. Results. Administration of the test feeds for 21 days to the diabetic rats of groups 4 and 5, resulted in 58.75% and 38.13% decreases in hyperglycemia and amelioration of their elevated urinary protein, glucose, SPGR, and relative kidney weights. The diabetic rats administered cocoyam incorporated feeds, had 2.71% and 19.52% increases in weight and growth rates, the diabetic rats administered unripe plantain incorporated feeds had 5.12% and 29.52% decreases in weight and growth rates while the diabetic control rats had 28.69%, 29.46%, 248.9% and 250.14% decreases in weights and growth rates. The cocoyam incorporated feeds contained higher antioxidants, minerals and phytochemicals except alkaloids than unripe plantain feed. Conclusion. Cocoyam and unripe plantain could be useful in the management of diabetic nephropathy.

  3. Brothers and reduction of the birth weight of later-born siblings

    DEFF Research Database (Denmark)

    Nielsen, Henriette Svarre; Mortensen, Laust; Nygaard, Ulrikka

    2008-01-01

    It has been speculated whether maternal immune responses against male-specific minor histocompatibility (H-Y) antigens affect pregnancies negatively. This study explores, on a population level, whether previous births of boys compared with girls are associated with a decrease in birth weight...... of later-born siblings. The population was identified in the Danish Birth Registry and consisted of all Danish women who gave birth to their first-born singleton from 1980 to 1998. The women were followed until 2004, and their subsequent births were recorded. A total of 545,839 second- to fourth......-born children were identified. The authors used linear regression to analyze the association between sex of preceding children and birth weight of subsequent siblings. Brothers compared with sisters reduced the birth weight of later-born siblings. One or two brothers, respectively, reduced the mean birth weight...

  4. Prenatal organochlorine compound exposure, rapid weight gain, and overweight in infancy.

    Science.gov (United States)

    Mendez, Michelle A; Garcia-Esteban, Raquel; Guxens, Mónica; Vrijheid, Martine; Kogevinas, Manolis; Goñi, Fernando; Fochs, Silvia; Sunyer, Jordi

    2011-02-01

    Although it has been hypothesized that fetal exposure to endocrine-disrupting chemicals may increase obesity risk, empirical data are limited, and it is uncertain how early in life any effects may begin. We explored whether prenatal exposure to several organochlorine compounds (OCs) is associated with rapid growth in the first 6 months of life and body mass index (BMI) later in infancy. Data come from the INMA (Infancia y Medio-Ambiente) Child and Environment birth cohort in Spain, which recruited 657 women in early pregnancy. Rapid growth during the first 6 months was defined as a change in weight-for-age z-scores > 0.67, and elevated BMI at 14 months, as a z-score ≥ the 85th percentile. Generalized linear models were used to estimate the risk of rapid growth or elevated BMI associated with 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (DDE), hexachlorobenzene, β-hexachlorohexane, and polychlorinated biphenyls in first-trimester maternal serum. After multivariable adjustment including other OCs, DDE exposure above the first quartile was associated with doubling of the risk of rapid growth among children of normal-weight (BMI < 25 kg/m2), but not overweight, mothers. DDE was also associated with elevated BMI at 14 months (relative risk per unit increase in log DDE = 1.50; 95% confidence interval, 1.11-2.03). Other OCs were not associated with rapid growth or elevated BMI after adjustment. In this study we found prenatal DDE exposure to be associated with rapid weight gain in the first 6 months and elevated BMI later in infancy, among infants of normal-weight mothers. More research exploring the potential role of chemical exposures in early-onset obesity is needed.

  5. Structure Learning in Stochastic Non-linear Dynamical Systems

    Science.gov (United States)

    Morris, R. D.; Smelyanskiy, V. N.; Luchinsky, D. G.

    2005-12-01

    A great many systems can be modeled in the non-linear dynamical systems framework, as x˙ = f(x) + ξ(t), where f(x) is the potential function for the system, and ξ(t) is the driving noise. Modeling the potential using a set of basis functions, we derive the posterior for the basis coefficients. A more challenging problem is to determine the set of basis functions that are required to model a particular system. We show that using the Bayesian Information Criteria (BIC) to rank models, and the beam search technique, that we can accurately determine the structure of simple non-linear dynamical system models, and the structure of the coupling between non-linear dynamical systems where the individual systems are known. This last case has important ecological applications, for example in predator-prey systems, where the very structure of the coupling between predator-prey pairs can have great ecological significance.

  6. Trajectory modeling of gestational weight: A functional principal component analysis approach.

    Directory of Open Access Journals (Sweden)

    Menglu Che

    Full Text Available Suboptimal gestational weight gain (GWG, which is linked to increased risk of adverse outcomes for a pregnant woman and her infant, is prevalent. In the study of a large cohort of Canadian pregnant women, our goals are to estimate the individual weight growth trajectory using sparsely collected bodyweight data, and to identify the factors affecting the weight change during pregnancy, such as prepregnancy body mass index (BMI, dietary intakes and physical activity. The first goal was achieved through functional principal component analysis (FPCA by conditional expectation. For the second goal, we used linear regression with the total weight gain as the response variable. The trajectory modeling through FPCA had a significantly smaller root mean square error (RMSE and improved adaptability than the classic nonlinear mixed-effect models, demonstrating a novel tool that can be used to facilitate real time monitoring and interventions of GWG. Our regression analysis showed that prepregnancy BMI had a high predictive value for the weight changes during pregnancy, which agrees with the published weight gain guideline.

  7. A modified linear algebraic approach to electron scattering using cubic splines

    International Nuclear Information System (INIS)

    Kinney, R.A.

    1986-01-01

    A modified linear algebraic approach to the solution of the Schrodiner equation for low-energy electron scattering is presented. The method uses a piecewise cubic-spline approximation of the wavefunction. Results in the static-potential and the static-exchange approximations for e - +H s-wave scattering are compared with unmodified linear algebraic and variational linear algebraic methods. (author)

  8. Effects of inclusion Aspergillus niger fermented shrimp waste meal in broiler diets on live performance and digestive organ weight

    Directory of Open Access Journals (Sweden)

    Irfan H. Djunaidi

    2009-06-01

    Full Text Available An experiment was conducted to evaluate the effect of the inclusion of different levels of shrimp waste meal fermented with Aspergillus niger (LUF in diets on growth performance and digestive organ weight of broilers. A total of 75 d-old chicks were randomly allocated to 5 (five treatments in 3 replication pens of 5 birds each. Treatments consisted of LUF inclusion of 0 (control, and 5, 7.5, 10 and 12,5% (P0, P1, P2, P3 and P4 in the diets. Birds were raised under standard condition and provided with feed and water ad-libitum. Feed and birds were weighed weekly up to 35 days to determine body weight, feed intake and feed conversion. At the end of experimental period, the birds were slaughatered and dressed up to determine carcass percentage and digestive organ weight. There was a significant negative linear response in body weight, feed consumption and feed conversion with increase of LUF more than 7.5% in the diets until 35 days of age, but % carcass was almost the same for all treatment. There was no significant response in digestive organ weight with increasing levels of LUF. The present result indicated that LUF could be considered as a potential feed ingredient as protein source of broiler but its inclusion should be limited until 7.5% of the diet to maintain growth performance and digestive organ weight.

  9. Fast and local non-linear evolution of steep wave-groups on deep water: A comparison of approximate models to fully non-linear simulations

    International Nuclear Information System (INIS)

    Adcock, T. A. A.; Taylor, P. H.

    2016-01-01

    The non-linear Schrödinger equation and its higher order extensions are routinely used for analysis of extreme ocean waves. This paper compares the evolution of individual wave-packets modelled using non-linear Schrödinger type equations with packets modelled using fully non-linear potential flow models. The modified non-linear Schrödinger Equation accurately models the relatively large scale non-linear changes to the shape of wave-groups, with a dramatic contraction of the group along the mean propagation direction and a corresponding extension of the width of the wave-crests. In addition, as extreme wave form, there is a local non-linear contraction of the wave-group around the crest which leads to a localised broadening of the wave spectrum which the bandwidth limited non-linear Schrödinger Equations struggle to capture. This limitation occurs for waves of moderate steepness and a narrow underlying spectrum

  10. Vaping to lose weight: Predictors of adult e-cigarette use for weight loss or control.

    Science.gov (United States)

    Morean, Meghan E; Wedel, Amelia V

    2017-03-01

    Some traditional cigarette smokers are motivated to smoke to lose weight or control their weight. The current study evaluated whether a subset of adult e-cigarette users reported vaping to lose or control their weight and examined potential predictors of vaping for weight management. Adult e-cigarette users (n=459) who reported wanting to lose weight or maintain their weight completed an anonymous online survey. Participants reported on demographics, vaping frequency, e-cigarette nicotine content, cigarette smoking status, preferred e-cigarette/e-liquid flavors, current weight status (i.e., overweight, underweight), use of dieting strategies associated with anorexia and bulimia, lifetime history of binge eating, self-discipline, and impulse control. Binary logistic regression was used to examine whether vaping for weight loss/control was associated with the aforementioned variables. Participants who reported vaping for weight loss/control (13.5%) were more likely to vape frequently (adjOR=1.15; 95% CI [1.00, 1.31]); be overweight (adjOR=2.80; [1.33, 5.90]); restrict calories (adjOR=2.23; [1.13, 4.42]); have poor impulse control (adjOR=0.59; [0.41, 0.86]); and prefer coffee- (adjOR=2.92; [1.47, 5.80]) or vanilla-flavored e-liquid (adjOR=7.44; [1.56, 36.08]). A subset of adult e-cigarette users reported vaping for weight loss/control, raising concerns about expanded, scientifically unsubstantiated uses of e-cigarettes. Identifying where individuals obtain information about vaping for weight loss (e.g., e-cigarette ads, Internet) and whether weight-related motives promote e-cigarette initiation among e-cigarette naïve individuals is important to informing regulatory efforts. Further research also is needed to better understand the link between e-liquid flavors and weight loss motivations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Drude weight and optical conductivity of a two-dimensional heavy-hole gas with k-cubic spin-orbit interactions

    Energy Technology Data Exchange (ETDEWEB)

    Mawrie, Alestin; Ghosh, Tarun Kanti [Department of Physics, Indian Institute of Technology-Kanpur, Kanpur 208 016 (India)

    2016-01-28

    We present a detailed theoretical study on zero-frequency Drude weight and optical conductivity of a two-dimensional heavy-hole gas (2DHG) with k-cubic Rashba and Dresselhaus spin-orbit interactions. The presence of k-cubic spin-orbit couplings strongly modifies the Drude weight in comparison to the electron gas with k-linear spin-orbit couplings. For large hole density and strong k-cubic spin-orbit couplings, the density dependence of Drude weight deviates from the linear behavior. We establish a relation between optical conductivity and the Berry connection. Unlike two-dimensional electron gas with k-linear spin-orbit couplings, we explicitly show that the optical conductivity does not vanish even for equal strength of the two spin-orbit couplings. We attribute this fact to the non-zero Berry phase for equal strength of k-cubic spin-orbit couplings. The least photon energy needed to set in the optical transition in hole gas is one order of magnitude smaller than that of electron gas. Types of two van Hove singularities appear in the optical spectrum are also discussed.

  12. KIR and HLA-C: Immunogenetic regulation of human birth weight

    Directory of Open Access Journals (Sweden)

    Lydia E. Farrell

    2014-12-01

    Full Text Available Pregnancies resulting in very small or very large babies are at higher risk of obstetric complications with increased morbidity for both mother and baby. Using data from the Medical Birth Registry of Norway we have shown how human birth weight is still subject to stabilizing selection. Particular combinations of maternal/fetal immune genes have been implicated in pregnancies resulting in a low birth weight baby (<5th birth weight centile. More specifically, an inhibitory maternal KIRAA genotype with a paternally derived fetal HLA-C2 ligand. At the other end of the birth weight spectrum the presence of an activating maternal KIR2DS1 gene is associated with increased birth weight in linear or logistic regression analyses of all pregnancies >5th centile (p=0.005, OR=2.65. Thus, inhibitory maternal KIR combined with fetal HLA-C2 is more frequently associated with low birth weight, whereas activating maternal KIR with fetal HLA-C2 ligand is associated with increasing birth weight. Our findings using the MoBa cohort have replicated the association of KIR and HLA-C seen in poor placentation, and confirm the importance of maternal/fetal immune gene interactions in determining the outcome of pregnancy.

  13. On the Linear Stability of the Fifth-Order WENO Discretization

    KAUST Repository

    Motamed, Mohammad

    2010-10-03

    We study the linear stability of the fifth-order Weighted Essentially Non-Oscillatory spatial discretization (WENO5) combined with explicit time stepping applied to the one-dimensional advection equation. We show that it is not necessary for the stability domain of the time integrator to include a part of the imaginary axis. In particular, we show that the combination of WENO5 with either the forward Euler method or a two-stage, second-order Runge-Kutta method is linearly stable provided very small time step-sizes are taken. We also consider fifth-order multistep time discretizations whose stability domains do not include the imaginary axis. These are found to be linearly stable with moderate time steps when combined with WENO5. In particular, the fifth-order extrapolated BDF scheme gave superior results in practice to high-order Runge-Kutta methods whose stability domain includes the imaginary axis. Numerical tests are presented which confirm the analysis. © Springer Science+Business Media, LLC 2010.

  14. Association of Body Weight and Body Mass Index with Bone Mineral Density in Women and Men from Kosovo.

    Science.gov (United States)

    Rexhepi, Sylejman; Bahtiri, Elton; Rexhepi, Mjellma; Sahatciu-Meka, Vjollca; Rexhepi, Blerta

    2015-08-01

    Body weight and body mass index (BMI) are considered potentially modifiable determinants of bone mass. Therefore, the aim of this study was to explore the association between body weight and body mass index (BMI) with total hip and lumbar spine bone mineral density (BMD). This cross-sectional study included a population of 100 women and 32 men from Kosovo into three BMI groups. All the study subjects underwent dual-energy X-ray absorptiometry (DXA) measurements. Total hip BMD levels of obese menopausal and premenopausal women and men were significantly higher compared to overweight or normal weight subjects, while lumbar spine BMD levels of only menopausal women and men were higher among obese subjects. Age-adjusted linear regression analysis showed that BMI is a significant independent associate of lumbar spine and total hip BMD in menopausal women and men. Despite positive association between BMI and lumbar spine and total hip BMD in menopausal women, presence of more obese and osteoporotic subjects among menopausal women represent a population at risk for fractures because of poor balance and frequent falls; therefore, both obesity and osteoporosis prevention efforts should begin early on in life.

  15. Clusters of week-specific maternal gestational weight gain pattern and their association with birthweight: an observational cohort study.

    Science.gov (United States)

    Liang, Huan; Yin, Chuanmin; Dong, Xinran; Acharya, Ganesh; Li, Xiaotian

    2017-10-01

    Gestational weight gain varies widely among different populations, and an inappropriate gestational weight gain is associated with adverse pregnancy outcomes. We aimed to investigate week-specific serial changes in gestational weight gain in an urban Chinese population to derive clusters of gestational weight gain patterns and explore the impact of gestational weight gain patterns on birthweight. This was an observational cohort study of 6130 women delivered at a university hospital in Shanghai, China. Pre-pregnancy bodyweight, height, week-specific and total gestational weight gain, pregnancy outcome and birthweight were extracted using electronic medical records. The association between gestational weight gain and gestational age was tested using linear regression, and week-specific reference percentiles for gestational weight gain were calculated. Hierarchical clustering was used to derive gestational weight gain clusters. Mean birthweight among the clusters was compared using Dunnet's test. We found a significant linear association between gestational weight gain and gestational age (r = 0.56; p gain pattern were identified. The birthweight significantly correlated with gestational weight gain (r = 0.28; p gain throughout the pregnancy, the mean birthweight among the clusters that had abnormal gestational weight gain (inadequate or excessive) in the third trimester was significantly different (p gain (between 5 and 95 percentile) in the third-trimester had similar mean birthweight. Women with abnormal gestational weight gain before the third-trimester still had a fair chance of delivering a normal birthweight baby if their gestational weight gain was normal in the third-trimester, suggesting that interventions started even late in pregnancy may have a positive effect on fetal growth. © 2017 Nordic Federation of Societies of Obstetrics and Gynecology.

  16. Approximation of functions in two variables by some linear positive operators

    Directory of Open Access Journals (Sweden)

    Mariola Skorupka

    1995-12-01

    Full Text Available We introduce some linear positive operators of the Szasz-Mirakjan type in the weighted spaces of continuous functions in two variables. We study the degree of the approximation of functions by these operators. The similar results for functions in one variable are given in [5]. Some operators of the Szasz-Mirakjan type are examined also in [3], [4].

  17. Linear minimax estimation for random vectors with parametric uncertainty

    KAUST Repository

    Bitar, E

    2010-06-01

    In this paper, we take a minimax approach to the problem of computing a worst-case linear mean squared error (MSE) estimate of X given Y , where X and Y are jointly distributed random vectors with parametric uncertainty in their distribution. We consider two uncertainty models, PA and PB. Model PA represents X and Y as jointly Gaussian whose covariance matrix Λ belongs to the convex hull of a set of m known covariance matrices. Model PB characterizes X and Y as jointly distributed according to a Gaussian mixture model with m known zero-mean components, but unknown component weights. We show: (a) the linear minimax estimator computed under model PA is identical to that computed under model PB when the vertices of the uncertain covariance set in PA are the same as the component covariances in model PB, and (b) the problem of computing the linear minimax estimator under either model reduces to a semidefinite program (SDP). We also consider the dynamic situation where x(t) and y(t) evolve according to a discrete-time LTI state space model driven by white noise, the statistics of which is modeled by PA and PB as before. We derive a recursive linear minimax filter for x(t) given y(t).

  18. Cytotoxicity of polycations: Relationship of molecular weight and the hydrolytic theory of the mechanism of toxicity.

    Science.gov (United States)

    Monnery, Bryn D; Wright, Michael; Cavill, Rachel; Hoogenboom, Richard; Shaunak, Sunil; Steinke, Joachim H G; Thanou, Maya

    2017-04-15

    The mechanism of polycation cytotoxicity and the relationship to polymer molecular weight is poorly understood. To gain an insight into this important phenomenon a range of newly synthesised uniform (near monodisperse) linear polyethylenimines, commercially available poly(l-lysine)s and two commonly used PEI-based transfectants (broad 22kDa linear and 25kDa branched) were tested for their cytotoxicity against the A549 human lung carcinoma cell line. Cell membrane damage assays (LDH release) and cell viability assays (MTT) showed a strong relationship to dose and polymer molecular weight, and increasing incubation times revealed that even supposedly "non-toxic" low molecular weight polymers still damage cell membranes. The newly proposed mechanism of cell membrane damage is acid catalysed hydrolysis of lipidic phosphoester bonds, which was supported by observations of the hydrolysis of DOPC liposomes. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  19. Associations of neighbourhood walkability indices with weight gain.

    Science.gov (United States)

    Koohsari, Mohammad Javad; Oka, Koichiro; Shibata, Ai; Liao, Yung; Hanibuchi, Tomoya; Owen, Neville; Sugiyama, Takemi

    2018-04-03

    Inconsistent associations of neighbourhood walkability with adults' body weight have been reported. Most studies examining the relationships of walkability and adiposity are cross-sectional in design. We examined the longitudinal relationships of two walkability indices - conventional walkability and space syntax walkability, and their individual components, with weight change among adults over four years. Data were from the Physical Activity in Localities and Community study in Adelaide, Australia. In 2003-2004, 2650 adults living in 154 Census Collection Districts (CCDs) returned baseline questionnaires; in 2007-2008, the follow-up survey was completed by 1098. Participants reported their weight at baseline and at follow-up. Neighbourhood walkability indices were calculated using geographic information systems and space syntax software. Linear marginal models using generalized estimating equations with robust standard errors were fitted to examine associations of the two walkability indices and their individual components with the weight at follow-up, adjusting for baseline weight, socio-demographic variables, and spatial clustering at the level of CCD. The overall mean weight gain over four years was 1.5 kg. The two walkability indices were closely correlated (r = 0.76, p walkability indices and weight change. Among walkability components, there was a marginally significant negative association between space syntax measure of street integration and weight change: one standard deviation increment in street integration was associated with 0.31 kg less weight gain (p = 0.09). Using a prospective study design and a novel space-syntax based measure of walkability, we were not able to identify relationships between neighbourhood walkability with weight gain. This is consistent with other inconclusive findings on the built environment and obesity. Research on the built environment and adults' weight gain may need to consider not just local environments but

  20. Error Estimation for the Linearized Auto-Localization Algorithm

    Directory of Open Access Journals (Sweden)

    Fernando Seco

    2012-02-01

    Full Text Available The Linearized Auto-Localization (LAL algorithm estimates the position of beacon nodes in Local Positioning Systems (LPSs, using only the distance measurements to a mobile node whose position is also unknown. The LAL algorithm calculates the inter-beacon distances, used for the estimation of the beacons’ positions, from the linearized trilateration equations. In this paper we propose a method to estimate the propagation of the errors of the inter-beacon distances obtained with the LAL algorithm, based on a first order Taylor approximation of the equations. Since the method depends on such approximation, a confidence parameter τ is defined to measure the reliability of the estimated error. Field evaluations showed that by applying this information to an improved weighted-based auto-localization algorithm (WLAL, the standard deviation of the inter-beacon distances can be improved by more than 30% on average with respect to the original LAL method.