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Sample records for additional independent variables

  1. Independent, dependent, and other variables in healthcare and chaplaincy research.

    PubMed

    Flannelly, Laura T; Flannelly, Kevin J; Jankowski, Katherine R B

    2014-01-01

    This article begins by defining the term variable and the terms independent variable and dependent variable, providing examples of each. It then proceeds to describe and discuss synonyms for the terms independent variable and dependent variable, including treatment, intervention, predictor, and risk factor, and synonyms for dependent variable, such as response variables and outcomes. The article explains that the terms extraneous, nuisance, and confounding variables refer to any variable that can interfere with the ability to establish relationships between independent variables and dependent variables, and it describes ways to control for such confounds. It further explains that even though intervening, mediating, and moderating variables explicitly alter the relationship between independent variables and dependent variables, they help to explain the causal relationship between them. In addition, the article links terminology about variables with the concept of levels of measurement in research.

  2. Problems Identifying Independent and Dependent Variables

    ERIC Educational Resources Information Center

    Leatham, Keith R.

    2012-01-01

    This paper discusses one step from the scientific method--that of identifying independent and dependent variables--from both scientific and mathematical perspectives. It begins by analyzing an episode from a middle school mathematics classroom that illustrates the need for students and teachers alike to develop a robust understanding of…

  3. Independent prognostic variables in acute myeloid leukaemia.

    PubMed

    Smith, Matthew L; Hills, Robert K; Grimwade, David

    2011-01-01

    Acute myeloid leukaemia (AML) is one of the most common haematological malignancies and is increasing in frequency due to an ageing population. Whilst remission will be achieved in up to 80% of those receiving intensive chemotherapy, the main variables precluding cure are the treatment-related mortality and relapse rates. Decisions on intensification, de-escalation and allografting rely on the ability to divide an apparently homogeneous group according to risk. A wide range of clinical, cytogenetic and molecular variables may be used to inform this task. Cytogenetic and molecular characterisation has already identified subgroups, such as acute promyelocytic leukaemia (APL) with t(15;17)/PML-RARA and AML with FLT3 mutation for which targeted therapies are available, and further molecularly defined groups who may be potential candidates for this approach are likely to be identified in the future. This review examines the range of established clinical and diagnostic parameters that should be used in assessing prognosis for a patient with AML and looks ahead to an expanding repertoire of potential variables that are currently under evaluation.

  4. Computer optimization program finds values for several independent variables that minimize a dependent variable

    NASA Technical Reports Server (NTRS)

    Warech, E. J.

    1967-01-01

    Computer program finds values of independent variables which minimize the dependent variable. This optimization program has been used on the F-1 and J-2 engine programs to establish minimum film coolant requirements.

  5. On the minimum of independent geometrically distributed random variables

    NASA Technical Reports Server (NTRS)

    Ciardo, Gianfranco; Leemis, Lawrence M.; Nicol, David

    1994-01-01

    The expectations E(X(sub 1)), E(Z(sub 1)), and E(Y(sub 1)) of the minimum of n independent geometric, modifies geometric, or exponential random variables with matching expectations differ. We show how this is accounted for by stochastic variability and how E(X(sub 1))/E(Y(sub 1)) equals the expected number of ties at the minimum for the geometric random variables. We then introduce the 'shifted geometric distribution' and show that there is a unique value of the shift for which the individual shifted geometric and exponential random variables match expectations both individually and in the minimums.

  6. Additional security features for optically variable foils

    NASA Astrophysics Data System (ADS)

    Marshall, Allan C.; Russo, Frank

    1998-04-01

    For thousands of years, man has exploited the attraction and radiance of pure gold to adorn articles of great significance. Today, designers decorate packaging with metallic gold foils to maintain the prestige of luxury items such as perfumes, chocolates, wine and whisky, and to add visible appeal and value to wide range of products. However, today's products do not call for the hand beaten gold leaf of the Ancient Egyptians, instead a rapid production technology exists which makes use of accurately coated thin polymer films and vacuum deposited metallic layers. Stamping Foils Technology is highly versatile since several different layers may be combined into one product, each providing a different function. Not only can a foil bring visual appeal to an article, it can provide physical and chemical resistance properties and also protect an article from human forms of interference, such as counterfeiting, copying or tampering. Stamping foils have proved to be a highly effective vehicle for applying optical devices to items requiring this type of protection. Credit cards, bank notes, personal identification documents and more recently high value packaged items such as software and perfumes are protected by optically variable devices applied using stamping foil technology.

  7. Iterative Strain-Gage Balance Calibration Data Analysis for Extended Independent Variable Sets

    NASA Technical Reports Server (NTRS)

    Ulbrich, Norbert Manfred

    2011-01-01

    A new method was developed that makes it possible to use an extended set of independent calibration variables for an iterative analysis of wind tunnel strain gage balance calibration data. The new method permits the application of the iterative analysis method whenever the total number of balance loads and other independent calibration variables is greater than the total number of measured strain gage outputs. Iteration equations used by the iterative analysis method have the limitation that the number of independent and dependent variables must match. The new method circumvents this limitation. It simply adds a missing dependent variable to the original data set by using an additional independent variable also as an additional dependent variable. Then, the desired solution of the regression analysis problem can be obtained that fits each gage output as a function of both the original and additional independent calibration variables. The final regression coefficients can be converted to data reduction matrix coefficients because the missing dependent variables were added to the data set without changing the regression analysis result for each gage output. Therefore, the new method still supports the application of the two load iteration equation choices that the iterative method traditionally uses for the prediction of balance loads during a wind tunnel test. An example is discussed in the paper that illustrates the application of the new method to a realistic simulation of temperature dependent calibration data set of a six component balance.

  8. An impossibility theorem for parameter independent hidden variable theories

    NASA Astrophysics Data System (ADS)

    Leegwater, Gijs

    2016-05-01

    Recently, Roger Colbeck and Renato Renner (C&R) have claimed that '[n]o extension of quantum theory can have improved predictive power' (Colbeck & Renner, 2011, 2012b). If correct, this is a spectacular impossibility theorem for hidden variable theories, which is more general than the theorems of Bell (1964) and Leggett (2003). Also, C&R have used their claim in attempt to prove that a system's quantum-mechanical wave function is in a one-to-one correspondence with its 'ontic' state (Colbeck & Renner, 2012a). C&R's claim essentially means that in any hidden variable theory that is compatible with quantum-mechanical predictions, probabilities of measurement outcomes are independent of these hidden variables. This makes such variables otiose. On closer inspection, however, the generality and validity of the claim can be contested. First, it is based on an assumption called 'Freedom of Choice'. As the name suggests, this assumption involves the independence of an experimenter's choice of measurement settings. But in the way C&R define this assumption, a no-signalling condition is surreptitiously presupposed, making the assumption less innocent than it sounds. When using this definition, any hidden variable theory violating parameter independence, such as Bohmian Mechanics, is immediately shown to be incompatible with quantum-mechanical predictions. Also, the argument of C&R is hard to follow and their mathematical derivation contains several gaps, some of which cannot be closed in the way they suggest. We shall show that these gaps can be filled. The issue with the 'Freedom of Choice' assumption can be circumvented by explicitly assuming parameter independence. This makes the result less general, but better founded. We then obtain an impossibility theorem for hidden variable theories satisfying parameter independence only. As stated above, such hidden variable theories are impossible in the sense that any supplemental variables have no bearing on outcome probabilities

  9. Canonical orbital elements in terms of an arbitrary independent variable

    NASA Technical Reports Server (NTRS)

    Bond, V. R.; Janin, G.

    1981-01-01

    Within the framework of the Hamiltonian mechanics in the extended phase space, a set of canonical elements of the Delaunay type is developed in terms of an arbitary independent angular variable. Application to the four classical anomalies - eccentric, true, elliptic, and mean - is presented. Particular attention is given to the generalized time equation and its conjugate energy equation.

  10. Nonparametric Independence Screening in Sparse Ultra-High Dimensional Additive Models.

    PubMed

    Fan, Jianqing; Feng, Yang; Song, Rui

    2011-06-01

    A variable screening procedure via correlation learning was proposed in Fan and Lv (2008) to reduce dimensionality in sparse ultra-high dimensional models. Even when the true model is linear, the marginal regression can be highly nonlinear. To address this issue, we further extend the correlation learning to marginal nonparametric learning. Our nonparametric independence screening is called NIS, a specific member of the sure independence screening. Several closely related variable screening procedures are proposed. Under general nonparametric models, it is shown that under some mild technical conditions, the proposed independence screening methods enjoy a sure screening property. The extent to which the dimensionality can be reduced by independence screening is also explicitly quantified. As a methodological extension, a data-driven thresholding and an iterative nonparametric independence screening (INIS) are also proposed to enhance the finite sample performance for fitting sparse additive models. The simulation results and a real data analysis demonstrate that the proposed procedure works well with moderate sample size and large dimension and performs better than competing methods.

  11. The development of the Poincare-similar elements with eccentric anomaly as the independent variable

    NASA Technical Reports Server (NTRS)

    Bond, V. R.

    1976-01-01

    A new set of element differential equations for the perturbed two-body motion is derived. The elements are canonical and are similar to the classical canonical Poincare elements, which have time as the independent variable. The phase space is extended by introducing the total energy and time as canonically conjugated variables. The new independent variable is, to within an additive constant, the eccentric anomaly. These elements are compared to the Kustaanheimo-Stiefel (KS) element differential equations, which also have the eccentric anomaly as the independent variable. For several numerical examples, the accuracy and stability of the new set are equal to those of the KS solution. This comparable accuracy result can probably be attributed to the fact that both sets have the same time element and very similar energy elements. The new set has only 8 elements, compared to 10 elements for the KS set. Both sets are free from singularities due to vanishing eccentricity and inclination.

  12. Spinning compact binary : Independent variables and dynamically preserved spin configurations

    SciTech Connect

    Gergely, Laszlo Arpad

    2010-04-15

    We establish the set of independent variables suitable to monitor the complicated evolution of the spinning compact binary during the inspiral. Our approach is valid up to the second post-Newtonian order, including leading order spin-orbit, spin-spin and mass quadrupole-mass monopole effects, for generic (noncircular, nonspherical) orbits. Then, we analyze the conservative spin dynamics in terms of these variables. We prove that the only binary black hole configuration allowing for spin precessions with equal angular velocities about a common instantaneous axis roughly aligned to the normal of the osculating orbit, is the equal mass and parallel (aligned or antialigned) spin configuration. This analytic result puts limitations on what particular configurations can be selected in numerical investigations of compact binary evolutions, even in those including only the last orbits of the inspiral.

  13. Microindentation in bone: hardness variation with five independent variables.

    PubMed

    Johnson, Wesley M; Rapoff, Andrew J

    2007-04-01

    Microindentation is an investigational tool often used to determine hardness and other derived material properties of the material bone. This study explored the variation of microindentation hardness results with five independent variables. The variables were: applied mass, dwell time, drying time, time between indentation and measurement, and distance between the center of an indentation and the edge of other indentations and pores. These variables were selected because they represented a reasonable range of specimen investigational steps. We also investigated the cross sections of typical indentation residual impressions to determine the degree of material pile-up at the edges of the impressions. We found that microindentation hardness varied with applied mass and with distance between the indentation and neighboring indentations and pores but not with the other variables. Our recommended minimum applied mass is 0.10 kg versus a previously published value of 0.05 kg. We also found no discernable material pile-up at the residual impression edges, in contrast to reports of others.

  14. The conditional independences between variables derived from two independent identically distributed Markov random fields when pairwise order is ignored.

    PubMed

    Thomas, Alun

    2010-09-01

    A result for the equivalence of conditional independence graphs of ordered and unordered vector random variables from first-order Markov models is extended to arbitrary forests. The result is relevant to estimating graphical models for linkage disequilibrium between genetic loci. It explains why, in terms of the conditional independence structure, it sometimes does not matter whether you consider haplotypes or genotypes.

  15. A provisional effective evaluation when errors are present in independent variables

    NASA Technical Reports Server (NTRS)

    Gurin, L. S.

    1983-01-01

    Algorithms are examined for evaluating the parameters of a regression model when there are errors in the independent variables. The algorithms are fast and the estimates they yield are stable with respect to the correlation of errors and measurements of both the dependent variable and the independent variables.

  16. Decreasing Cloudiness Over China: An Updated Analysis Examining Additional Variables

    SciTech Connect

    Kaiser, D.P.

    2000-01-14

    As preparation of the IPCC's Third Assessment Report takes place, one of the many observed climate variables of key interest is cloud amount. For several nations of the world, there exist records of surface-observed cloud amount dating back to the middle of the 20th Century or earlier, offering valuable information on variations and trends. Studies using such databases include Sun and Groisman (1999) and Kaiser and Razuvaev (1995) for the former Soviet Union, Angel1 et al. (1984) for the United States, Henderson-Sellers (1986) for Europe, Jones and Henderson-Sellers (1992) for Australia, and Kaiser (1998) for China. The findings of Kaiser (1998) differ from the other studies in that much of China appears to have experienced decreased cloudiness over recent decades (1954-1994), whereas the other land regions for the most part show evidence of increasing cloud cover. This paper expands on Kaiser (1998) by analyzing trends in additional meteorological variables for Chi na [station pressure (p), water vapor pressure (e), and relative humidity (rh)] and extending the total cloud amount (N) analysis an additional two years (through 1996).

  17. 10 CFR 431.175 - Additional requirements applicable to non-Voluntary Independent Certification Program participants.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Additional requirements applicable to non-Voluntary Independent Certification Program participants. 431.175 Section 431.175 Energy DEPARTMENT OF ENERGY ENERGY... requirements applicable to non-Voluntary Independent Certification Program participants. If you are...

  18. Teaching About Crowding: Students as an Independent Variable.

    ERIC Educational Resources Information Center

    Banziger, George

    1982-01-01

    Introductory psychology students were introduced to the topic of crowding by experiencing high density in physical arrangements of the classroom. Results did not demonstrate the complexity and possible interactive effects of crowding variables. Students gained insights into other aspects of crowding, experimental design, and interpreting…

  19. Independent Sampling vs Interitem Dependencies in Whole Report Processing: Contributions of Processing Architecture and Variable Attention.

    PubMed

    Busey, Thomas A.; Townsend, James T.

    2001-04-01

    All current models of visual whole report processing assume perceptual independence among the displayed items in which the perceptual processing of individual items is not affected by other items in the display. However, models proposed by Townsend (1981, Acta Psychologica 47, 149-173), Shibuya and Bundesen (1988, Journal of Experimental Psychology: Human Perception and Performance 14, 591-600), and Bundesen (1990, Psychological Review 97, 523-547) contain postperceptual buffers that must predict negative dependencies. The perceptual-independence assumption forms what we term the modal model class. A recent example of a model that assumes perceptual independence is the Independent Sampling Model of Loftus, Busey, and Senders (1993, Perception and Psychophysics 54, 535-554). The fundamental independence assumption has only been directly tested once before, where tests revealed no dependencies except those produced by guessing. The present study tests the independence assumption using several different statistics and, contrary to most extant models of whole report, finds significant positive dependence. Poisson models do predict a positive dependence and we develop a succinctly parameterized version, the Weighted Path Poisson Model, which allows the finishing order to be a weighted probabilistic mechanism. However, it does not predict the data quite as well as a new model, the Variable Attention Model, which allows independence within trials (unlike the Poisson models). This model assumes that attention (or, potentially, other aspects such as signal quality) varies widely across trials, thus predicting an overall positive dependence. Intuitions for and against the competing models are discussed. In addition, we show, through mimicking formulae, that models which contain the proper qualitative type of dependence structure can be cast in either serial or parallel form. Copyright 2001 Academic Press.

  20. Research Standards in Early Intervention: Defining, Describing, and Measuring the Independent Variable.

    ERIC Educational Resources Information Center

    LeLaurin, Kathryn; Wolery, Mark

    1992-01-01

    This paper considers methodological issues related to the independent variable in early intervention research. Three standards are proposed: (1) use theory to guide research; (2) provide operational definitions of independent variables, quantify them, and describe how they relate to theory; and (3) measure treatment fidelity. Three levels of…

  1. Independent variable timestep integration of individual neurons for network simulations

    PubMed Central

    Lytton, William; Hines, Michael

    2009-01-01

    Realistic neural networks involve the co-existence of stiff, coupled, continuous differential equations arising from the integrations of individual neurons, with the discrete events with delays used for modeling synaptic connections. We present here an integration method, the local variable time-step method (lvardt) that utilizes separate variable step integrators for individual neurons in the network. Cells which are undergoing excitation tend to have small time-steps and cells which are at rest with little synaptic input tend to have large time-steps. A synaptic input to a cell causes re-initialization of only that cell’s integrator without affecting the integration of other cells. We illustrated the use of lvardt on three models: a worst-case synchronizing mutual-inhibition model, a best-case synfire chain model, and a more realistic thalamocortical network model. PMID:15829094

  2. Geostatistical independent simulation of spatially correlated soil variables

    NASA Astrophysics Data System (ADS)

    Boluwade, Alaba; Madramootoo, Chandra A.

    2015-12-01

    The selection of best management practices to reduce soil and water pollution often requires estimation of soil properties. It is important to find an efficient and robust technique to simulate spatially correlated soils parameters. Co-kriging and co-simulation are techniques that can be used. These methods are limited in terms of computer simulation due to the problem of solving large co-kriging systems and difficulties in fitting a valid model of coregionalization. The order of complexity increases as the number of covariables increases. This paper presents a technique for the conditional simulation of a non-Gaussian vector random field on point support scale. The technique is termed Independent Component Analysis (ICA). The basic principle underlining ICA is the determination of a linear representation of non-Gaussian data so that the components are considered statistically independent. With such representation, it would be easy and more computationally efficient to develop direct variograms for the components. The process is presented in two stages. The first stage involves the ICA decomposition. The second stage involves sequential Gaussian simulation of the generated components (which are derived from the first stage). This technique was applied for spatially correlated extractable cations such as magnesium (Mg) and iron (Fe) in a Canadian watershed. This paper has a strong application in stochastic quantification of uncertainties of soil attributes in soil remediation and soil rehabilitation.

  3. Regression Mixture Models: Does Modeling the Covariance Between Independent Variables and Latent Classes Improve the Results?

    PubMed

    Lamont, Andrea E; Vermunt, Jeroen K; Van Horn, M Lee

    2016-01-01

    Regression mixture models are increasingly used as an exploratory approach to identify heterogeneity in the effects of a predictor on an outcome. In this simulation study, we tested the effects of violating an implicit assumption often made in these models; that is, independent variables in the model are not directly related to latent classes. Results indicate that the major risk of failing to model the relationship between predictor and latent class was an increase in the probability of selecting additional latent classes and biased class proportions. In addition, we tested whether regression mixture models can detect a piecewise relationship between a predictor and outcome. Results suggest that these models are able to detect piecewise relations but only when the relationship between the latent class and the predictor is included in model estimation. We illustrate the implications of making this assumption through a reanalysis of applied data examining heterogeneity in the effects of family resources on academic achievement. We compare previous results (which assumed no relation between independent variables and latent class) to the model where this assumption is lifted. Implications and analytic suggestions for conducting regression mixture based on these findings are noted.

  4. A note on independent variables for restricted three-body problems.

    NASA Technical Reports Server (NTRS)

    Heppenheimer, T. A.

    1971-01-01

    In studies of the elliptic restricted three-body problem, the true anomaly of the motion of the primaries is often used as the independent variable. The equations of motion then show invariancy in form from the circular case. It is of interest whether other independent variables exist, such that the invariant form of the equations is maintained. It is found that true anomaly is the only such variable.

  5. Assessment of Relative Velocity as Independent Variable for Space Shuttle First Stage Guidance Attitude Command Tables

    NASA Technical Reports Server (NTRS)

    Kimbrough, M.

    1977-01-01

    The selection of relative velocity as the independent variable for the space shuttle first stage guidance attitude command tables was assessed to support the first stage guidance point design. The criterion for selecting the independent variable for first stage open loop guidance is to reduce or minimize performance dispersions, primarily those affecting structural loads. The products of angle of attack and angle of sideslip times dynamic pressure are used as load indicators, and minimizing their dispersions will indicate a minimum loads dispersion. Relative velocity is shown to be an acceptable steering independent variable.

  6. The covariation of independent and dependant variables in neurofeedback: a proposal framework to identify cognitive processes and brain activity variables.

    PubMed

    Micoulaud-Franchi, Jean-Arthur; Quiles, Clélia; Fond, Guillaume; Cermolacce, Michel; Vion-Dury, Jean

    2014-05-01

    This methodological article proposes a framework for analysing the relationship between cognitive processes and brain activity using variables measured by neurofeedback (NF) carried out by functional Magnetic Resonance Imagery (fMRI NF). Cognitive processes and brain activity variables can be analysed as either the dependant variable or the independent variable. Firstly, we propose two traditional approaches, defined in the article as the "neuropsychological" approach (NP) and the "psychophysiology" approach (PP), to extract dependent and independent variables in NF protocols. Secondly, we suggest that NF can be inspired by the style of inquiry used in neurophenomenology. fMRI NF allows participants to experiment with his or her own cognitive processes and their effects on brain region of interest (ROI) activations simultaneously. Thus, we suggest that fMRI NF could be improved by implementing "the elicitation interview method", which allows the investigator to gather relevant verbatim from participants' introspection on subjective experiences.

  7. On bounds in Poisson approximation for distributions of independent negative-binomial distributed random variables.

    PubMed

    Hung, Tran Loc; Giang, Le Truong

    2016-01-01

    Using the Stein-Chen method some upper bounds in Poisson approximation for distributions of row-wise triangular arrays of independent negative-binomial distributed random variables are established in this note. PMID:26844026

  8. On bounds in Poisson approximation for distributions of independent negative-binomial distributed random variables.

    PubMed

    Hung, Tran Loc; Giang, Le Truong

    2016-01-01

    Using the Stein-Chen method some upper bounds in Poisson approximation for distributions of row-wise triangular arrays of independent negative-binomial distributed random variables are established in this note.

  9. Multiple correlation computer program determines relationships between several independent and dependent variables

    NASA Technical Reports Server (NTRS)

    Kaspar, H.; Newsbaum, J. B.

    1967-01-01

    Relationships between independent and dependent variables are determined by multiple correlation computer program. This is applied to research and experimental design and development of complex hardware and components that require test programs.

  10. Antimicrobial combinations: Bliss independence and Loewe additivity derived from mechanistic multi-hit models.

    PubMed

    Baeder, Desiree Y; Yu, Guozhi; Hozé, Nathanaël; Rolff, Jens; Regoes, Roland R

    2016-05-26

    Antimicrobial peptides (AMPs) and antibiotics reduce the net growth rate of bacterial populations they target. It is relevant to understand if effects of multiple antimicrobials are synergistic or antagonistic, in particular for AMP responses, because naturally occurring responses involve multiple AMPs. There are several competing proposals describing how multiple types of antimicrobials add up when applied in combination, such as Loewe additivity or Bliss independence. These additivity terms are defined ad hoc from abstract principles explaining the supposed interaction between the antimicrobials. Here, we link these ad hoc combination terms to a mathematical model that represents the dynamics of antimicrobial molecules hitting targets on bacterial cells. In this multi-hit model, bacteria are killed when a certain number of targets are hit by antimicrobials. Using this bottom-up approach reveals that Bliss independence should be the model of choice if no interaction between antimicrobial molecules is expected. Loewe additivity, on the other hand, describes scenarios in which antimicrobials affect the same components of the cell, i.e. are not acting independently. While our approach idealizes the dynamics of antimicrobials, it provides a conceptual underpinning of the additivity terms. The choice of the additivity term is essential to determine synergy or antagonism of antimicrobials.This article is part of the themed issue 'Evolutionary ecology of arthropod antimicrobial peptides'. PMID:27160596

  11. The Variable Transition State in Polar Additions to Pi Bonds

    ERIC Educational Resources Information Center

    Weiss, Hilton M.

    2010-01-01

    A vast majority of polar additions of Bronsted acids to alkynes involve a termolecular transition state. With strong acids, considerable positive charge is developed on carbon and Markovnikov addition predominates. In less acidic solutions, however, the reaction is much slower and the transition state more closely resembles the olefinic product.…

  12. Automated determination of chemical functionalisation addition routes based on magnetic susceptibility and nucleus independent chemical shifts

    NASA Astrophysics Data System (ADS)

    Van Lier, G.; Ewels, C. P.; Geerlings, P.

    2008-07-01

    We present a modified version of our previously reported meta-code SACHA, for systematic analysis of chemical addition. The code automates the generation of structures, running of quantum chemical codes, and selection of preferential isomers based on chosen selection rules. While the selection rules for the previous version were based on the total system energy, predicting purely thermodynamic addition patterns, we examine here the possibility of using other system parameters, notably magnetic susceptibility as a descriptor of global aromaticity, and nucleus independent chemical shifts (NICS) as local aromaticity descriptor.

  13. Independent effects of warming and nitrogen addition on plant phenology in the Inner Mongolian steppe

    PubMed Central

    Xia, Jianyang; Wan, Shiqiang

    2013-01-01

    Background and Aims Phenology is one of most sensitive traits of plants in response to regional climate warming. Better understanding of the interactive effects between warming and other environmental change factors, such as increasing atmosphere nitrogen (N) deposition, is critical for projection of future plant phenology. Methods A 4-year field experiment manipulating temperature and N has been conducted in a temperate steppe in northern China. Phenology, including flowering and fruiting date as well as reproductive duration, of eight plant species was monitored and calculated from 2006 to 2009. Key Results Across all the species and years, warming significantly advanced flowering and fruiting time by 0·64 and 0·72 d per season, respectively, which were mainly driven by the earliest species (Potentilla acaulis). Although N addition showed no impact on phenological times across the eight species, it significantly delayed flowering time of Heteropappus altaicus and fruiting time of Agropyron cristatum. The responses of flowering and fruiting times to warming or N addition are coupled, leading to no response of reproductive duration to warming or N addition for most species. Warming shortened reproductive duration of Potentilla bifurca but extended that of Allium bidentatum, whereas N addition shortened that of A. bidentatum. No interactive effect between warming and N addition was found on any phenological event. Such additive effects could be ascribed to the species-specific responses of plant phenology to warming and N addition. Conclusions The results suggest that the warming response of plant phenology is larger in earlier than later flowering species in temperate grassland systems. The effects of warming and N addition on plant phenology are independent of each other. These findings can help to better understand and predict the response of plant phenology to climate warming concurrent with other global change driving factors. PMID:23585496

  14. 10 CFR 431.174 - Additional requirements applicable to Voluntary Independent Certification Program participants.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Independent Certification Program participants. 431.174 Section 431.174 Energy DEPARTMENT OF ENERGY ENERGY... requirements applicable to Voluntary Independent Certification Program participants. (a) Description of Voluntary Independent Certification Program participant. For purposes of this subpart, a manufacturer...

  15. An overview of techniques for dealing with large numbers of independent variables in epidemiologic studies.

    PubMed

    Dohoo, I R; Ducrot, C; Fourichon, C; Donald, A; Hurnik, D

    1997-01-01

    Many studies of health and production problems in livestock involve the simultaneous evaluation of large numbers of risk factors. These analyses may be complicated by a number of problems including: multicollinearity (which arises because many of the risk factors may be related (correlated) to each other), confounding, interaction, problems related to sample size (and hence the power of the study), and the fact that many associations are evaluated from a single dataset. This paper focuses primarily on the problem of multicollinearity and discusses a number of techniques for dealing with this problem. However, some of the techniques discussed may also help to deal with the other problems identified above. The first general approach to dealing with multicollinearity involves reducing the number of independent variables prior to investigating associations with the disease. Techniques to accomplish this include: (1) excluding variables after screening for associations among independent variables; (2) creating indices or scores which combine data from multiple factors into a single variable; (3) creating a smaller set of independent variables through the use of multivariable techniques such as principal components analysis or factor analysis. The second general approach is to use appropriate steps and statistical techniques to investigate associations between the independent variables and the dependent variable. A preliminary screening of these associations may be performed using simple statistical tests. Subsequently, multivariable techniques such as linear or logistic regression or correspondence analysis can be used to identify important associations. The strengths and limitations of these techniques are discussed and the techniques are demonstrated using a dataset from a recent study of risk factors for pneumonia in swine. Emphasis is placed on comparing correspondence analysis with other techniques as it has been used less in the epidemiology literature.

  16. Relationship Between Field Dependence - Field Independence, Piaget Conservation Tasks and School Variables.

    ERIC Educational Resources Information Center

    Wicker, Tommie E.; O'Tuel, Frances S.

    This study investigates relationships among conservation, field dependence/independence, school variables, achievement, screening measures, sex and race. A total of 124 first, second and third graders in a Southern rural school were administered 8 typical Piagetian conservation tasks (PCT), Children's Embedded Figures Test (CEFT), Comprehensive…

  17. Recommendations for Reporting Independent Variables in Outcome Studies of Early and Intensive Behavioral Intervention for Autism

    ERIC Educational Resources Information Center

    Lechago, Sarah A.; Carr, James E.

    2008-01-01

    Early and intensive behavioral intervention (EIBI) has been established as an effective treatment for autism. However, the complexity and intensity of EIBI programs make it difficult to fully report all critical aspects of the independent variable. Consequently, scientific reports of EIBI outcomes have been criticized for providing less than…

  18. Human Performance Technology (HPT): An Examination of Definitions through Dependent and Independent Variables.

    ERIC Educational Resources Information Center

    Irlbeck, Sonja A.

    2002-01-01

    Provides a chronological perspective of human performance technology (HPT) definitions and an evaluation of them in terms of independent and dependent variables. Discusses human competence and performance technology and compares the definitions with the goals that have been articulated for HPT. (Author/LRW)

  19. Variability in Physical Activity Assessed with Accelerometer Is an Independent Predictor of Mortality in CHF Patients

    PubMed Central

    Melin, Michael; Hagerman, Inger; Gonon, Adrian; Gustafsson, Thomas; Rullman, Eric

    2016-01-01

    Aims Patients with heart failure often display a distinct pattern of walking characterized by short step-length and frequent short pauses. In the current study we sought to explore if qualitative aspects of movement have any additive value to established factors to predict all-cause mortality in patients with advanced heart failure. Methods and results 60 patients with advanced heart failure (NYHA III, peak VO2 <20 ml/kg and LVEF <35%) underwent symptom-limited CPX, echocardiography and routine chemistry. Physical activity was assessed using an accelerometer worn attached to the waist during waking hours for 7 consecutive days. The heart-failure survival score (HFSS) was calculated for each patient. All accelerometer-derived variables were analyzed with regard to all-cause mortality and added to a baseline model utilizing HFSS scores. HFSS score was significantly associated with the incidence of death (P<0.001; c-index 0.71; CI, 0.67–0.73). The addition of peak skewness to the HFSS model significantly improved the predictive ability with an increase in c-index to 0.74 (CI, 0.69–0.78), likelihood ratio P<0.02, establishing skewness as a predictor of increased event rates when accounting for baseline risk. Conclusion The feature skewness, a measure of asymmetry in the intensity level of periods of high physical activity, was identified to be predictive of all-cause mortality independent of the established prognostic model–HFSS and peak VO2. The findings from the present study emphasize the use of accelerometer analysis in clinical practice to make more accurate prognoses in addition to extract features of physical activity relevant to functional classification. PMID:27054323

  20. Independence.

    ERIC Educational Resources Information Center

    Stephenson, Margaret E.

    2000-01-01

    Discusses the four planes of development and the periods of creation and crystallization within each plane. Identifies the type of independence that should be achieved by the end of the first two planes of development. Maintains that it is through individual work on the environment that one achieves independence. (KB)

  1. Datafish Multiphase Data Mining Technique to Match Multiple Mutually Inclusive Independent Variables in Large PACS Databases.

    PubMed

    Kelley, Brendan P; Klochko, Chad; Halabi, Safwan; Siegal, Daniel

    2016-06-01

    Retrospective data mining has tremendous potential in research but is time and labor intensive. Current data mining software contains many advanced search features but is limited in its ability to identify patients who meet multiple complex independent search criteria. Simple keyword and Boolean search techniques are ineffective when more complex searches are required, or when a search for multiple mutually inclusive variables becomes important. This is particularly true when trying to identify patients with a set of specific radiologic findings or proximity in time across multiple different imaging modalities. Another challenge that arises in retrospective data mining is that much variation still exists in how image findings are described in radiology reports. We present an algorithmic approach to solve this problem and describe a specific use case scenario in which we applied our technique to a real-world data set in order to identify patients who matched several independent variables in our institution's picture archiving and communication systems (PACS) database. PMID:26572132

  2. Datafish Multiphase Data Mining Technique to Match Multiple Mutually Inclusive Independent Variables in Large PACS Databases.

    PubMed

    Kelley, Brendan P; Klochko, Chad; Halabi, Safwan; Siegal, Daniel

    2016-06-01

    Retrospective data mining has tremendous potential in research but is time and labor intensive. Current data mining software contains many advanced search features but is limited in its ability to identify patients who meet multiple complex independent search criteria. Simple keyword and Boolean search techniques are ineffective when more complex searches are required, or when a search for multiple mutually inclusive variables becomes important. This is particularly true when trying to identify patients with a set of specific radiologic findings or proximity in time across multiple different imaging modalities. Another challenge that arises in retrospective data mining is that much variation still exists in how image findings are described in radiology reports. We present an algorithmic approach to solve this problem and describe a specific use case scenario in which we applied our technique to a real-world data set in order to identify patients who matched several independent variables in our institution's picture archiving and communication systems (PACS) database.

  3. The Use of Additional GPS Frequencies to Independently Determine Tropospheric Water Vapor Profiles

    NASA Technical Reports Server (NTRS)

    Herman, B.M.; Feng, D.; Flittner, D. E.; Kursinski, E. R.

    2000-01-01

    It is well known that the currently employed L1 and L2 GPS/MET frequencies (1.2 - 1.6) Ghz) do not allow for the separation of water vapor and density (or temperature) from active microwave occultation measurements in regions of the troposphere warmer than 240 K Therefore, additional information must be used, from other types of measurements and weather analyses, to recover water vapor (and temperature) profiles. Thus in data sparse regions, these inferred profiles can be subject to larger errors than would result in data rich regions. The use of properly selected additional GPS frequencies enables a direct, independent measurement of the absorption associated with the water vapor profile, which may then be used in the standard GPS/MET retrievals to obtain a more accurate determination of atmospheric temperature throughout the water vapor layer. This study looks at the use of microwave crosslinks in the region of the 22 Ghz water vapor absorption line for this purpose. An added advantage of using 22 Ghz frequencies is that they are only negligibly affected by the ionosphere in contrast to the large effect at the GPS frequencies. The retrieval algorithm uses both amplitude and phase measurements to obtain profiles of atmospheric pressure, temperature and water water vapor pressure with a vertical resolution of 1 km or better. This technique also provides the cloud liquid water content along the ray path, which is in itself an important element in climate monitoring. Advantages of this method include the ability to make measurements in the presence of clouds and the use of techniques and technology proven through the GPS/MET experiment and several of NASA's planetary exploration missions. Simulations demonstrating this method will be presented for both clear and cloudy sky conditions.

  4. Variable Selection for Sparse High-Dimensional Nonlinear Regression Models by Combining Nonnegative Garrote and Sure Independence Screening

    PubMed Central

    Xue, Hongqi; Wu, Yichao; Wu, Hulin

    2013-01-01

    In many regression problems, the relations between the covariates and the response may be nonlinear. Motivated by the application of reconstructing a gene regulatory network, we consider a sparse high-dimensional additive model with the additive components being some known nonlinear functions with unknown parameters. To identify the subset of important covariates, we propose a new method for simultaneous variable selection and parameter estimation by iteratively combining a large-scale variable screening (the nonlinear independence screening, NLIS) and a moderate-scale model selection (the nonnegative garrote, NNG) for the nonlinear additive regressions. We have shown that the NLIS procedure possesses the sure screening property and it is able to handle problems with non-polynomial dimensionality; and for finite dimension problems, the NNG for the nonlinear additive regressions has selection consistency for the unimportant covariates and also estimation consistency for the parameter estimates of the important covariates. The proposed method is applied to simulated data and a real data example for identifying gene regulations to illustrate its numerical performance. PMID:25170239

  5. Generalized additive modeling with implicit variable selection by likelihood-based boosting.

    PubMed

    Tutz, Gerhard; Binder, Harald

    2006-12-01

    The use of generalized additive models in statistical data analysis suffers from the restriction to few explanatory variables and the problems of selection of smoothing parameters. Generalized additive model boosting circumvents these problems by means of stagewise fitting of weak learners. A fitting procedure is derived which works for all simple exponential family distributions, including binomial, Poisson, and normal response variables. The procedure combines the selection of variables and the determination of the appropriate amount of smoothing. Penalized regression splines and the newly introduced penalized stumps are considered as weak learners. Estimates of standard deviations and stopping criteria, which are notorious problems in iterative procedures, are based on an approximate hat matrix. The method is shown to be a strong competitor to common procedures for the fitting of generalized additive models. In particular, in high-dimensional settings with many nuisance predictor variables it performs very well. PMID:17156269

  6. Estimated parameters as independent variables - with an application to the costs of electric-generating units

    SciTech Connect

    Schmalensee, R.; Joskow, P.L.

    1984-01-01

    The cost of a piece of capital equipment, like an electric-generating unit, is a function of a variety of unit-specific attributes. Some of these attributes can be observed directly without error (such as size), but others (such as the reliability or efficiency of the equipment), cannot be. However, estimates of the unobservable quality attributes can often be obtained from time-series data on expost performance, and these estimates can in turn be used as data on the unobservable attributes that appear as exogenous variables in a cost equation. The authors consider estimation of linear models in which observation-specific (firm, plant, household, individual) attributes appear as exogenous variables, but these attributes cannot be observed directly. Rather, they assume that estimates of the relevant observation-specific attributes, along with the associated covariance matrix, can be computed using data on variables (such as ex post performance) that do not appear directly in the primary model of interest. A maximum-likelihood technique for using such estimates as independent variables in cross-section regression analysis is derived. The solution to the measurement-error problem is interpretable as nonlinear (Theil-Goldberger) mixed estimation. The method is applied to the estimation of a construction cost relationship for electric-generating units.

  7. Variability of doublecortin-associated dendrite maturation in adult hippocampal neurogenesis is independent of the regulation of precursor cell proliferation

    PubMed Central

    Plümpe, Tobias; Ehninger, Dan; Steiner, Barbara; Klempin, Friederike; Jessberger, Sebastian; Brandt, Moritz; Römer, Benedikt; Rodriguez, Gerardo Ramirez; Kronenberg, Golo; Kempermann, Gerd

    2006-01-01

    Background In the course of adult hippocampal neurogenesis most regulation takes place during the phase of doublecortin (DCX) expression, either as pro-proliferative effect on precursor cells or as survival-promoting effect on postmitotic cells. We here obtained quantitative data about the proliferative population and the dynamics of postmitotic dendrite development during the period of DCX expression. The question was, whether any indication could be obtained that the initiation of dendrite development is timely bound to the exit from the cell cycle. Alternatively, the temporal course of morphological maturation might be subject to additional regulatory events. Results We found that (1) 20% of the DCX population were precursor cells in cell cycle, whereas more than 70% were postmitotic, (2) the time span until newborn cells had reached the most mature stage associated with DCX expression varied between 3 days and several weeks, (3) positive or negative regulation of precursor cell proliferation did not alter the pattern and dynamics of dendrite development. Dendrite maturation was largely independent of close contacts to astrocytes. Conclusion These data imply that dendrite maturation of immature neurons is initiated at varying times after cell cycle exit, is variable in duration, and is controlled independently of the regulation of precursor cell proliferation. We conclude that in addition to the major regulatory events in cell proliferation and selective survival, additional micro-regulatory events influence the course of adult hippocampal neurogenesis. PMID:17105671

  8. Performance variability, impulsivity errors and the impact of incentives as gender-independent endophenotypes for ADHD

    PubMed Central

    Uebel, Henrik; Albrecht, Björn; Asherson, Philip; Börger, Norbert A.; Butler, Louise; Chen, Wai; Christiansen, Hanna; Heise, Alexander; Kuntsi, Jonna; Schäfer, Ulrike; Andreou, Penny; Manor, Iris; Marco, Rafaela; Meidad, Sheera; Miranda, Ana; Mulligan, Aisling; Oades, Robert D.; van der Meere, Jaap; Faraone, Stephen V.; Rothenberger, Aribert; Banaschewski, Tobias

    2010-01-01

    Background Attention-deficit hyperactivity disorder (ADHD) is one of the most common and highly heritable child psychiatric disorders. There is strong evidence that children with ADHD show slower and more variable responses in tasks such as Go/Nogo tapping aspects of executive functions like sustained attention and response control which may be modulated by motivational factors and/or state-regulation processes. The aim of this study was (1) to determine if these executive functions may constitute an endophenotype for ADHD; (2) to investigate for the first time whether known modulators of these executive functions may also be familial and (3) to explore whether gender has an impact on these measures. Methods Two hundred and five children with ADHD combined type, 173 nonaffected biological siblings and 53 controls with no known family history of ADHD were examined using a Go/Nogo-Task in the framework of a multi-centre study. Performance-measures and modulating effects of event-rate and incentives were examined. Shared familial effects on these measures were assessed, and the influence of gender was tested. Results Children with ADHD responded more slowly and variably than nonaffected siblings or controls. Nonaffected siblings showed intermediate scores for reaction-time variability, false alarms and omission errors under fast and slow event rates. A slower event-rate did not led to reduced performance specific for ADHD. In the incentive condition, mean reaction times speeded-up and became less variable only in children with ADHD and their nonaffected siblings, while accuracy was improved in all groups. Males responded faster, but also committed more false alarms. There were no interactions of group by gender. Conclusions Reaction-time variability and accuracy parameters could be useful neuropsychological endophenotypes for ADHD. Performance modulating effects of incentives suggested a familially-driven motivational dysfunction which may play an important role on

  9. Major histocompatibility complex harbors widespread genotypic variability of non-additive risk of rheumatoid arthritis including epistasis

    PubMed Central

    Wei, Wen-Hua; Bowes, John; Plant, Darren; Viatte, Sebastien; Yarwood, Annie; Massey, Jonathan; Worthington, Jane; Eyre, Stephen

    2016-01-01

    Genotypic variability based genome-wide association studies (vGWASs) can identify potentially interacting loci without prior knowledge of the interacting factors. We report a two-stage approach to make vGWAS applicable to diseases: firstly using a mixed model approach to partition dichotomous phenotypes into additive risk and non-additive environmental residuals on the liability scale and secondly using the Levene’s (Brown-Forsythe) test to assess equality of the residual variances across genotype groups per marker. We found widespread significant (P < 2.5e-05) vGWAS signals within the major histocompatibility complex (MHC) across all three study cohorts of rheumatoid arthritis. We further identified 10 epistatic interactions between the vGWAS signals independent of the MHC additive effects, each with a weak effect but jointly explained 1.9% of phenotypic variance. PTPN22 was also identified in the discovery cohort but replicated in only one independent cohort. Combining the three cohorts boosted power of vGWAS and additionally identified TYK2 and ANKRD55. Both PTPN22 and TYK2 had evidence of interactions reported elsewhere. We conclude that vGWAS can help discover interacting loci for complex diseases but require large samples to find additional signals. PMID:27109064

  10. Nonlinear analysis of heart rate variability within independent frequency components during the sleep-wake cycle.

    PubMed

    Vigo, Daniel E; Dominguez, Javier; Guinjoan, Salvador M; Scaramal, Mariano; Ruffa, Eduardo; Solernó, Juan; Siri, Leonardo Nicola; Cardinali, Daniel P

    2010-04-19

    Heart rate variability (HRV) is a complex signal that results from the contribution of different sources of oscillation related to the autonomic nervous system activity. Although linear analysis of HRV has been applied to sleep studies, the nonlinear dynamics of HRV underlying frequency components during sleep is less known. We conducted a study to evaluate nonlinear HRV within independent frequency components in wake status, slow-wave sleep (SWS, stages III or IV of non-rapid eye movement sleep), and rapid-eye-movement sleep (REM). The sample included 10 healthy adults. Polysomnography was performed to detect sleep stages. HRV was studied globally during each phase and then very low frequency (VLF), low frequency (LF) and high frequency (HF) components were separated by means of the wavelet transform algorithm. HRV nonlinear dynamics was estimated with sample entropy (SampEn). A higher SampEn was found when analyzing global variability (Wake: 1.53+/-0.28, SWS: 1.76+/-0.32, REM: 1.45+/-0.19, p=0.005) and VLF variability (Wake: 0.13+/-0.03, SWS: 0.19+/-0.03, REM: 0.14+/-0.03, p<0.001) at SWS. REM was similar to wake status regarding nonlinear HRV. We propose nonlinear HRV is a useful index of the autonomic activity that characterizes the different sleep-wake cycle stages.

  11. Increased rainfall variability and N addition accelerate litter decomposition in a restored prairie.

    PubMed

    Schuster, Michael J

    2016-03-01

    Anthropogenic nitrogen deposition and projected increases in rainfall variability (the frequency of drought and heavy rainfall events) are expected to strongly influence ecosystem processes such as litter decomposition. However, how these two global change factors interact to influence litter decomposition is largely unknown. I examined how increased rainfall variability and nitrogen addition affected mass and nitrogen loss of litter from two tallgrass prairie species, Schizachyrium scoparium and Solidago canadensis, and isolated the effects of each during plant growth and during litter decomposition. I increased rainfall variability by consolidating ambient rainfall into larger events and simulated chronic nitrogen deposition using a slow-release urea fertilizer. S. scoparium litter decay was more strongly regulated by the treatments applied during plant growth than by those applied during decomposition. During plant growth, increased rainfall variability resulted in S. scoparium litter that subsequently decomposed more slowly and immobilized more nitrogen than litter grown under ambient conditions, whereas nitrogen addition during plant growth accelerated subsequent mass loss of S. scoparium litter. In contrast, S. canadensis litter mass and N losses were enhanced under either N addition or increased rainfall variability both during plant growth and during decomposition. These results suggest that ongoing changes in rainfall variability and nitrogen availability are accelerating nutrient cycling in tallgrass prairies through their combined effects on litter quality, environmental conditions, and plant community composition. PMID:26216200

  12. Nitrogen Addition and Warming Independently Influence the Belowground Micro-Food Web in a Temperate Steppe

    PubMed Central

    Li, Qi; Bai, Huahua; Liang, Wenju; Xia, Jianyang; Wan, Shiqiang; van der Putten, Wim H.

    2013-01-01

    Climate warming and atmospheric nitrogen (N) deposition are known to influence ecosystem structure and functioning. However, our understanding of the interactive effect of these global changes on ecosystem functioning is relatively limited, especially when it concerns the responses of soils and soil organisms. We conducted a field experiment to study the interactive effects of warming and N addition on soil food web. The experiment was established in 2006 in a temperate steppe in northern China. After three to four years (2009–2010), we found that N addition positively affected microbial biomass and negatively influenced trophic group and ecological indices of soil nematodes. However, the warming effects were less obvious, only fungal PLFA showed a decreasing trend under warming. Interestingly, the influence of N addition did not depend on warming. Structural equation modeling analysis suggested that the direct pathway between N addition and soil food web components were more important than the indirect connections through alterations in soil abiotic characters or plant growth. Nitrogen enrichment also affected the soil nematode community indirectly through changes in soil pH and PLFA. We conclude that experimental warming influenced soil food web components of the temperate steppe less than N addition, and there was little influence of warming on N addition effects under these experimental conditions. PMID:23544140

  13. Developing Independent Listening Skills for English as an Additional Language Students

    ERIC Educational Resources Information Center

    Picard, Michelle; Velautham, Lalitha

    2016-01-01

    This paper describes an action research project to develop online, self-access listening resources mirroring the authentic academic contexts experienced by graduate university students. Current listening materials for English as an Additional Language (EAL) students mainly use Standard American English or Standard British pronunciation, and far…

  14. Discrete and continuous variables for measurement-device-independent quantum cryptography

    DOE PAGES

    Xu, Feihu; Curty, Marcos; Qi, Bing; Qian, Li; Lo, Hoi-Kwong

    2015-11-16

    In a recent Article in Nature Photonics, Pirandola et al.1 claim that the achievable secret key rates of discrete-variable (DV) measurementdevice- independent (MDI) quantum key distribution (QKD) (refs 2,3) are “typically very low, unsuitable for the demands of a metropolitan network” and introduce a continuous-variable (CV) MDI QKD protocol capable of providing key rates which, they claim, are “three orders of magnitude higher” than those of DV MDI QKD. We believe, however, that the claims regarding low key rates of DV MDI QKD made by Pirandola et al.1 are too pessimistic. Here in this paper, we show that the secretmore » key rate of DV MDI QKD with commercially available high-efficiency single-photon detectors (SPDs) (for example, see http://www.photonspot.com/detectors and http://www.singlequantum.com) and good system alignment is typically rather high and thus highly suitable for not only long-distance communication but also metropolitan networks.« less

  15. Discrete and continuous variables for measurement-device-independent quantum cryptography

    SciTech Connect

    Xu, Feihu; Curty, Marcos; Qi, Bing; Qian, Li; Lo, Hoi-Kwong

    2015-11-16

    In a recent Article in Nature Photonics, Pirandola et al.1 claim that the achievable secret key rates of discrete-variable (DV) measurementdevice- independent (MDI) quantum key distribution (QKD) (refs 2,3) are “typically very low, unsuitable for the demands of a metropolitan network” and introduce a continuous-variable (CV) MDI QKD protocol capable of providing key rates which, they claim, are “three orders of magnitude higher” than those of DV MDI QKD. We believe, however, that the claims regarding low key rates of DV MDI QKD made by Pirandola et al.1 are too pessimistic. Here in this paper, we show that the secret key rate of DV MDI QKD with commercially available high-efficiency single-photon detectors (SPDs) (for example, see http://www.photonspot.com/detectors and http://www.singlequantum.com) and good system alignment is typically rather high and thus highly suitable for not only long-distance communication but also metropolitan networks.

  16. The development of the Poincare-similar elements with true anomaly as the independent variable

    NASA Technical Reports Server (NTRS)

    Mueller, A.

    1976-01-01

    In reference 1, the Hamiltonian of the unperturbed two-body problem in extended phase space is established. Depending on the type of time transformation, eight canonical elements were developed with the true anomaly or the eccentric anomaly as the independent variable. These two new sets, DS(phi) and DS(u), however contain singularities for small eccentricities and inclinations. In reference 2, these singularities are removed by a transformation from DS(u) to eight canonical PS(u) elements. In reference 3, the DS(phi) variables are transformed to the PS(phi) elements to remove the singularities. However, no direct relation was established between the eight canonical PS(phi) elements and the Cartesian coordinates. It is the purpose of this report to establish those relations and to develop the perturbed equations of motion in the PS(phi) space. This report also demonstrates the accuracy of this new set when it is applied to numerical orbit prediction problems.

  17. Addition of uridines to edited RNAs in trypanosome mitochondria occurs independently of transcription

    SciTech Connect

    Harris, M.E.; Moore, D.R.; Hajduk, S.L. )

    1990-07-05

    RNA editing is a novel RNA processing event of unknown mechanism that results in the introduction of nucleotides not encoded in the DNA into specific RNA molecules. We have examined the post-transcriptional addition of nucleotides into the mitochondrial RNA of Trypanosoma brucei. Utilizing an isolated organelle system we have determined that addition of uridines to edited RNAs does not require ongoing transcription. Trypanosome mitochondria incorporate CTP, ATP, and UTP into RNA in the absence of transcription. GTP is incorporated into RNA only as a result of the transcription process. Post-transcriptional CTP and ATP incorporation can be ascribed to known enzymatic activities. CTP is incorporated into tRNAs as a result of synthesis or turnover of their 3{prime} CCA sequences. ATP is incorporated into the 3{prime} CCA of tRNAs and into mitochondrial messenger RNAs due to polyadenylation. In the absence of transcription, UTP is incorporated into transcripts known to undergo editing, and the degree of UTP incorporation is consistent with the degree of editing occurring in these transcripts. Cytochrome b mRNAs, which contain a single editing site near their 5{prime} ends, are initially transcribed unedited at that site. Post-transcriptional labeling of cytochrome b mRNAs in the organelle with (alpha-32P)UTP results in the addition of uridines near the 5{prime} end of the RNA but not in a 3{prime} region which lacks an editing site. These results indicate that RNA editing is a post-transcriptional process in the mitochondria of trypanosomes.

  18. Additives

    NASA Technical Reports Server (NTRS)

    Smalheer, C. V.

    1973-01-01

    The chemistry of lubricant additives is discussed to show what the additives are chemically and what functions they perform in the lubrication of various kinds of equipment. Current theories regarding the mode of action of lubricant additives are presented. The additive groups discussed include the following: (1) detergents and dispersants, (2) corrosion inhibitors, (3) antioxidants, (4) viscosity index improvers, (5) pour point depressants, and (6) antifouling agents.

  19. Stochasticity and determinism: how density-independent and density-dependent processes affect population variability.

    PubMed

    Ohlberger, Jan; Rogers, Lauren A; Stenseth, Nils Chr

    2014-01-01

    A persistent debate in population ecology concerns the relative importance of environmental stochasticity and density dependence in determining variability in adult year-class strength, which contributes to future reproduction as well as potential yield in exploited populations. Apart from the strength of the processes, the timing of density regulation may affect how stochastic variation, for instance through climate, translates into changes in adult abundance. In this study, we develop a life-cycle model for the population dynamics of a large marine fish population, Northeast Arctic cod, to disentangle the effects of density-independent and density-dependent processes on early life-stages, and to quantify the strength of compensatory density dependence in the population. The model incorporates information from scientific surveys and commercial harvest, and dynamically links multiple effects of intrinsic and extrinsic factors on all life-stages, from eggs to spawners. Using a state-space approach we account for observation error and stochasticity in the population dynamics. Our findings highlight the importance of density-dependent survival in juveniles, indicating that this period of the life cycle largely determines the compensatory capacity of the population. Density regulation at the juvenile life-stage dampens the impact of stochastic processes operating earlier in life such as environmental impacts on the production of eggs and climate-dependent survival of larvae. The timing of stochastic versus regulatory processes thus plays a crucial role in determining variability in adult abundance. Quantifying the contribution of environmental stochasticity and compensatory mechanisms in determining population abundance is essential for assessing population responses to climate change and exploitation by humans. PMID:24893001

  20. A fuzzy adaptive network approach to parameter estimation in cases where independent variables come from an exponential distribution

    NASA Astrophysics Data System (ADS)

    Dalkilic, Turkan Erbay; Apaydin, Aysen

    2009-11-01

    In a regression analysis, it is assumed that the observations come from a single class in a data cluster and the simple functional relationship between the dependent and independent variables can be expressed using the general model; Y=f(X)+[epsilon]. However; a data cluster may consist of a combination of observations that have different distributions that are derived from different clusters. When faced with issues of estimating a regression model for fuzzy inputs that have been derived from different distributions, this regression model has been termed the [`]switching regression model' and it is expressed with . Here li indicates the class number of each independent variable and p is indicative of the number of independent variables [J.R. Jang, ANFIS: Adaptive-network-based fuzzy inference system, IEEE Transaction on Systems, Man and Cybernetics 23 (3) (1993) 665-685; M. Michel, Fuzzy clustering and switching regression models using ambiguity and distance rejects, Fuzzy Sets and Systems 122 (2001) 363-399; E.Q. Richard, A new approach to estimating switching regressions, Journal of the American Statistical Association 67 (338) (1972) 306-310]. In this study, adaptive networks have been used to construct a model that has been formed by gathering obtained models. There are methods that suggest the class numbers of independent variables heuristically. Alternatively, in defining the optimal class number of independent variables, the use of suggested validity criterion for fuzzy clustering has been aimed. In the case that independent variables have an exponential distribution, an algorithm has been suggested for defining the unknown parameter of the switching regression model and for obtaining the estimated values after obtaining an optimal membership function, which is suitable for exponential distribution.

  1. Confirmation of mass-independent Ni isotopic variability in iron meteorites

    NASA Astrophysics Data System (ADS)

    Steele, Robert C. J.; Elliott, Tim; Coath, Christopher D.; Regelous, Marcel

    2011-12-01

    We report high-precision analyses of internally-normalised Ni isotope ratios in 12 bulk iron meteorites. Our measurements of 60Ni/ 61Ni, 62Ni/ 61Ni and 64Ni/ 61Ni normalised to 58Ni/ 61Ni and expressed in parts per ten thousand (‱) relative to NIST SRM 986 as ɛ60Ni,ɛ62Ni and ɛ64Ni, vary by 0.146, 0.228 and 0.687, respectively. The precision on a typical analysis is 0.03‱, 0.05‱ and 0.08‱ for ɛ60Ni, ɛ62Ni and ɛ64Ni, respectively, which is comparable to our sample reproducibility. We show that this 'mass-independent' Ni isotope variability cannot be ascribed to interferences, inaccurate correction of instrumental or natural mass-dependent fractionation, fractionation controlled by nuclear field shift effects, nor the influence of cosmic ray spallation. These results thus document the presence of mass-independent Ni isotopic heterogeneity in bulk meteoritic samples, as previously proposed by Regelous et al. (2008) (EPSL 272, 330-338), but our new analyses are more precise and include determination of 64Ni. Intriguingly, we find that terrestrial materials do not yield homogenous internally-normalised Ni isotope compositions, which, as pointed out by Young et al. (2002) (GCA 66, 1095-1104), may be the expected result of using the exponential (kinetic) law and atomic masses to normalise all fractionation processes. The certified Ni isotope reference material NIST SRM 986 defines zero in this study, while appropriate ratios for the bulk silicate Earth are given by the peridotites JP-1 and DTS-2 and, relative to NIST SRM 986, yield deviations in ɛ60Ni, ɛ62Ni and ɛ64Ni of -0.006‱, 0.036‱ and 0.119‱, respectively. There is a strong positive correlation between ɛ64Ni and ɛ62Ni in iron meteorites analyses, with a slope of 3.03 ± 0.71. The variations of Ni isotope anomalies in iron meteorites are consistent with heterogeneous distribution of a nucleosynthetic component from a type Ia supernova into the proto-solar nebula.

  2. Design of Experiments with Multiple Independent Variables: A Resource Management Perspective on Complete and Reduced Factorial Designs

    ERIC Educational Resources Information Center

    Collins, Linda M.; Dziak, John J.; Li, Runze

    2009-01-01

    An investigator who plans to conduct an experiment with multiple independent variables must decide whether to use a complete or reduced factorial design. This article advocates a resource management perspective on making this decision, in which the investigator seeks a strategic balance between service to scientific objectives and economy.…

  3. A Note on the Calculation and Interpretation of the Delta-p Statistic for Categorical Independent Variables

    ERIC Educational Resources Information Center

    Cruce, Ty M.

    2009-01-01

    This methodological note illustrates how a commonly used calculation of the Delta-p statistic is inappropriate for categorical independent variables, and this note provides users of logistic regression with a revised calculation of the Delta-p statistic that is more meaningful when studying the differences in the predicted probability of an…

  4. The Relationship of Field Dependent/Independent Cognitive Styles, Stimuli Variability and Time Factor on Student Achievement.

    ERIC Educational Resources Information Center

    Atang, Christopher I.

    The effects of black and white and color illustrations on student achievement were studied to investigate the relationships between cognitive styles and instructional design. Field dependence (FD) and field independence (FI) were chosen as the cognitive style variables. Subjects were 85 freshman students in the Iowa State University Psychology…

  5. Additional Saturday rehabilitation improves functional independence and quality of life and reduces length of stay: a randomized controlled trial

    PubMed Central

    2013-01-01

    Background Many inpatients receive little or no rehabilitation on weekends. Our aim was to determine what effect providing additional Saturday rehabilitation during inpatient rehabilitation had on functional independence, quality of life and length of stay compared to 5 days per week of rehabilitation. Methods This was a multicenter, single-blind (assessors) randomized controlled trial with concealed allocation and 12-month follow-up conducted in two publically funded metropolitan inpatient rehabilitation facilities in Melbourne, Australia. Patients were eligible if they were adults (aged ≥18 years) admitted for rehabilitation for any orthopedic, neurological or other disabling conditions excluding those admitted for slow stream rehabilitation/geriatric evaluation and management. Participants were randomly allocated to usual care Monday to Friday rehabilitation (control) or to Monday to Saturday rehabilitation (intervention). The additional Saturday rehabilitation comprised physiotherapy and occupational therapy. The primary outcomes were functional independence (functional independence measure (FIM); measured on an 18 to 126 point scale), health-related quality of life (EQ-5D utility index; measured on a 0 to 1 scale, and EQ-5D visual analog scale; measured on a 0 to 100 scale), and patient length of stay. Outcome measures were assessed on admission, discharge (primary endpoint), and at 6 and 12 months post discharge. Results We randomly assigned 996 adults (mean (SD) age 74 (13) years) to Monday to Saturday rehabilitation (n = 496) or usual care Monday to Friday rehabilitation (n = 500). Relative to admission scores, intervention group participants had higher functional independence (mean difference (MD) 2.3, 95% confidence interval (CI) 0.5 to 4.1, P = 0.01) and health-related quality of life (MD 0.04, 95% CI 0.01 to 0.07, P = 0.009) on discharge and may have had a shorter length of stay by 2 days (95% CI 0 to 4, P = 0.1) when compared to

  6. A Risk Score with Additional Four Independent Factors to Predict the Incidence and Recovery from Metabolic Syndrome: Development and Validation in Large Japanese Cohorts

    PubMed Central

    Obokata, Masaru; Negishi, Kazuaki; Ohyama, Yoshiaki; Okada, Haruka; Imai, Kunihiko; Kurabayashi, Masahiko

    2015-01-01

    Background Although many risk factors for Metabolic syndrome (MetS) have been reported, there is no clinical score that predicts its incidence. The purposes of this study were to create and validate a risk score for predicting both incidence and recovery from MetS in a large cohort. Methods Subjects without MetS at enrollment (n = 13,634) were randomly divided into 2 groups and followed to record incidence of MetS. We also examined recovery from it in rest 2,743 individuals with prevalent MetS. Results During median follow-up of 3.0 years, 878 subjects in the derivation and 757 in validation cohorts developed MetS. Multiple logistic regression analysis identified 12 independent variables from the derivation cohort and initial score for subsequent MetS was created, which showed good discrimination both in the derivation (c-statistics 0.82) and validation cohorts (0.83). The predictability of the initial score for recovery from MetS was tested in the 2,743 MetS population (906 subjects recovered from MetS), where nine variables (including age, sex, γ-glutamyl transpeptidase, uric acid and five MetS diagnostic criteria constituents.) remained significant. Then, the final score was created using the nine variables. This score significantly predicted both the recovery from MetS (c-statistics 0.70, p<0.001, 78% sensitivity and 54% specificity) and incident MetS (c-statistics 0.80) with an incremental discriminative ability over the model derived from five factors used in the diagnosis of MetS (continuous net reclassification improvement: 0.35, p < 0.001 and integrated discrimination improvement: 0.01, p<0.001). Conclusions We identified four additional independent risk factors associated with subsequent MetS, developed and validated a risk score to predict both incident and recovery from MetS. PMID:26230621

  7. The influence of non-solvent addition on the independent and dependent parameters in roller electrospinning of polyurethane.

    PubMed

    Cengiz-Callioglu, Funda; Jirsak, Oldrich; Dayik, Mehmet

    2013-07-01

    This paper discusses the effects of 1,1,2,2 tetrachlorethylen (TCE) non-solvent addition on the independent (electrical conductivity, dielectric constant, surface tension and the theological properties of the solution etc.) and dependent parameters (number of Taylor cones per square meter (NTC/m2), spinning performance for one Taylor cone (SP/TC), total spinning performance (SP), fiber properties such as diameter, diameter uniformity, non-fibrous area) in roller electrospinning of polyurethane (PU). The same process parameters (voltage, distance of the electrodes, humidity, etc.) were applied for all solutions during the spinning process. According to the results, the effect of TCE non-solvent concentration on the dielectric constant, surface tension, rheological properties of the solution and also spinning performance was important statistically. Beside these results, TCE non-solvent concentration effects quality of fiber and nano web structure. Generally high fiber density, low non-fibrous percentage and uniform nanofibers were obtained from fiber morphology analyses.

  8. Use of generalised additive models to categorise continuous variables in clinical prediction

    PubMed Central

    2013-01-01

    Background In medical practice many, essentially continuous, clinical parameters tend to be categorised by physicians for ease of decision-making. Indeed, categorisation is a common practice both in medical research and in the development of clinical prediction rules, particularly where the ensuing models are to be applied in daily clinical practice to support clinicians in the decision-making process. Since the number of categories into which a continuous predictor must be categorised depends partly on the relationship between the predictor and the outcome, the need for more than two categories must be borne in mind. Methods We propose a categorisation methodology for clinical-prediction models, using Generalised Additive Models (GAMs) with P-spline smoothers to determine the relationship between the continuous predictor and the outcome. The proposed method consists of creating at least one average-risk category along with high- and low-risk categories based on the GAM smooth function. We applied this methodology to a prospective cohort of patients with exacerbated chronic obstructive pulmonary disease. The predictors selected were respiratory rate and partial pressure of carbon dioxide in the blood (PCO2), and the response variable was poor evolution. An additive logistic regression model was used to show the relationship between the covariates and the dichotomous response variable. The proposed categorisation was compared to the continuous predictor as the best option, using the AIC and AUC evaluation parameters. The sample was divided into a derivation (60%) and validation (40%) samples. The first was used to obtain the cut points while the second was used to validate the proposed methodology. Results The three-category proposal for the respiratory rate was ≤ 20;(20,24];> 24, for which the following values were obtained: AIC=314.5 and AUC=0.638. The respective values for the continuous predictor were AIC=317.1 and AUC=0.634, with no statistically

  9. Structure of the isotropic transport operators in three independent space variables

    NASA Technical Reports Server (NTRS)

    Abu-Shumays, I. K.; Bareiss, E. H.

    1969-01-01

    Based on the idea of separation of variables, a spectral theory for the three-dimensional, stationary, isotropic transport operator in a vector space of complex-valued Borel functions results in continuous sets of regular and generalized eigenfunctions.

  10. Moderate-to-Vigorous Physical Activity and Sedentary Behavior: Independent Associations With Body Composition Variables in Brazilian Children.

    PubMed

    Ferrari, Gerson Luis de Moraes; Oliveira, Luis Carlos; Araujo, Timoteo Leandro; Matsudo, Victor; Barreira, Tiago V; Tudor-Locke, Catrine; Katzmarzyk, Peter

    2015-08-01

    This study aimed to analyze the independent associations of accelerometer-determined sedentary behavior, physical activity, and steps/day with body composition variables in Brazilian children. 485 children wore accelerometers for 7 days. Variables included time in sedentary behavior and different physical activity intensities (light, moderate, vigorous, or moderate-to-vigorous) and steps/day. Body fat percentage was measured using a bioelectrical impedance scale, and BMI was calculated. Children spent 55.7% of the awake portion of the day in sedentary behavior, 37.6% in light physical activity, 4.6% in moderate physical activity, and 1.9% in vigorous physical activity. Moderate-to-vigorous physical activity and steps/day were negatively associated with body composition (BMI and body fat percentage) variables, independent of sex and sedentary behavior. Beta values were higher for vigorous physical activity than moderate physical activity. Vigorous physical activity was negatively associated with BMI (β-.1425) and body fat percentage (β-.3082; p < .0001). In boys, there were significant negative associations between moderate, vigorous, and moderate-to-vigorous physical activity and steps/day with body composition, and in girls, there was only a negative association with vigorous physical activity, independent of sedentary behavior. Moderate-to-vigorous physical activity and steps/day (in boys), but especially vigorous physical activity (in boys and girls), are associated with body composition, independent of sedentary behavior. Sedentary behavior was not related with any of the body composition variables once adjusted for moderate-to-vigorous physical activity.

  11. Field Dependence-Independence as a Variable in Second Language Cloze Test Performance.

    ERIC Educational Resources Information Center

    Stansfield, Charles; Hansen, Jacqueline

    1983-01-01

    A study of test performance and field dependent-independent (FD/I) cognitive style in 250 college students showed consistently positive correlation between FI and cloze test scores, and other measures such as final grade. It is suggested cloze tests may call forth cognitive restructuring capabilities more easily for more field independent…

  12. Achromatic recirculated chicane with fixed geometry and independently variable path length and momentum compaction

    DOEpatents

    Douglas, David R.; Neil, George R.

    2005-04-26

    A particle beam recirculated chicane geometry that, through the inducement of a pair of 180 degree bends directed by the poles of a pair of controllable magnetic fields allows for variation of dipole position, return loop radii and steering/focussing, thereby allowing the implementation of independent variation of path length and momentum compaction.

  13. Goal-directed and transfer-cue-elicited drug-seeking are dissociated by pharmacotherapy: evidence for independent additive controllers.

    PubMed

    Hogarth, Lee

    2012-07-01

    According to contemporary learning theory, drug-seeking behavior reflects the summation of 2 dissociable controllers. Whereas goal-directed drug-seeking is determined by the expected current incentive value of the drug, stimulus-elicited drug-seeking is determined by the expected probability of the drug independently of its current incentive value, and these 2 controllers contribute additively to observed drug-seeking. One applied prediction of this model is that smoking cessation pharmacotherapies selectively attenuate tonic but not cue-elicited craving because they downgrade the expected incentive value of the drug but leave expected probability intact. To test this, the current study examined whether nicotine replacement therapy (NRT) nasal spray would modify goal-directed tobacco choice in a human outcome devaluation procedure, but leave cue-elicited tobacco choice in a Pavlovian to instrumental transfer (PIT) procedure intact. Smokers (N= 96) first underwent concurrent choice training in which 2 responses earned tobacco or chocolate points, respectively. Participants then ingested either NRT nasal spray (1 mg) or chocolate (147 g) to devalue 1 outcome. Concurrent choice was then tested again in extinction to measure goal-directed control of choice, and in a PIT test to measure the extent to which tobacco and chocolate stimuli enhanced choice of the same outcome. It was found that NRT modified tobacco choice in the extinction test but not the extent to which the tobacco stimulus enhanced choice of the tobacco outcome in the PIT test. This dissociation suggests that the propensity to engage in drug-seeking is determined independently by the expected value and probability of the drug, and that pharmacotherapy has partial efficacy because it selectively effects expected drug value.

  14. Goal-directed and transfer-cue-elicited drug-seeking are dissociated by pharmacotherapy: evidence for independent additive controllers.

    PubMed

    Hogarth, Lee

    2012-07-01

    According to contemporary learning theory, drug-seeking behavior reflects the summation of 2 dissociable controllers. Whereas goal-directed drug-seeking is determined by the expected current incentive value of the drug, stimulus-elicited drug-seeking is determined by the expected probability of the drug independently of its current incentive value, and these 2 controllers contribute additively to observed drug-seeking. One applied prediction of this model is that smoking cessation pharmacotherapies selectively attenuate tonic but not cue-elicited craving because they downgrade the expected incentive value of the drug but leave expected probability intact. To test this, the current study examined whether nicotine replacement therapy (NRT) nasal spray would modify goal-directed tobacco choice in a human outcome devaluation procedure, but leave cue-elicited tobacco choice in a Pavlovian to instrumental transfer (PIT) procedure intact. Smokers (N= 96) first underwent concurrent choice training in which 2 responses earned tobacco or chocolate points, respectively. Participants then ingested either NRT nasal spray (1 mg) or chocolate (147 g) to devalue 1 outcome. Concurrent choice was then tested again in extinction to measure goal-directed control of choice, and in a PIT test to measure the extent to which tobacco and chocolate stimuli enhanced choice of the same outcome. It was found that NRT modified tobacco choice in the extinction test but not the extent to which the tobacco stimulus enhanced choice of the tobacco outcome in the PIT test. This dissociation suggests that the propensity to engage in drug-seeking is determined independently by the expected value and probability of the drug, and that pharmacotherapy has partial efficacy because it selectively effects expected drug value. PMID:22823420

  15. Combined effects of independent variables on yield and protein content of pectin extracted from sugar beet pulp by citric acid.

    PubMed

    Li, De-Qiang; Du, Guang-Ming; Jing, Wei-Wen; Li, Jun-Fang; Yan, Jia-Yu; Liu, Zhi-Yong

    2015-09-20

    The extraction of pectin from sugar beet pulp by citric acid was carried out under different conditions using Box-Behnken design for four independent variables (pH, temperature, time and liquid to solid ratio). The yield of sugar beet pulp pectin ranged from 6.3% to 23.0%, and the content of protein from 1.5% to 4.5%. All independent variables significantly affected the yield, and all variables except liquid to solid ratio significantly affected the protein content. The yield increased as decreasing pH of extracting solution, extending time and advancing temperature, and an opposite relationship of effects between variables and content of protein was obtained. The chemical composition of collected samples was determined. Moreover, from the results of emulsifying properties study, the extracted pectin from sugar beet pulp could prepare steady oil-in-water emulsions. Therefore, it was inferred that the extraction conditions could influence yield and protein content, resulting in different emulsifying property.

  16. Performance Variability, Impulsivity Errors and the Impact of Incentives as Gender-Independent Endophenotypes for ADHD

    ERIC Educational Resources Information Center

    Uebel, Henrik; Albrecht, Bjorn; Asherson, Philip; Borger, Norbert A.; Butler, Louise; Chen, Wai; Christiansen, Hanna; Heise, Alexander; Kuntsi, Jonna; Schafer, Ulrike; Andreou, Penny; Manor, Iris; Marco, Rafaela; Miranda, Ana; Mulligan, Aisling; Oades, Robert D.; van der Meere, Jaap; Faraone, Stephen V.; Rothenberger, Aribert; Banaschewski, Tobias

    2010-01-01

    Background: Attention-deficit hyperactivity disorder (ADHD) is one of the most common and highly heritable child psychiatric disorders. There is strong evidence that children with ADHD show slower and more variable responses in tasks such as Go/Nogo tapping aspects of executive functions like sustained attention and response control which may be…

  17. Neck Circumference, along with Other Anthropometric Indices, Has an Independent and Additional Contribution in Predicting Fatty Liver Disease

    PubMed Central

    Huang, Bi-xia; Zhu, Ming-fan; Wu, Ting; Zhou, Jing-ya; Liu, Yan; Chen, Xiao-lin; Zhou, Rui-fen; Wang, Li-jun; Chen, Yu-ming; Zhu, Hui-lian

    2015-01-01

    Background and Aim Previous studies have indicated that neck circumference is a valuable predictor for obesity and metabolic syndrome, but little evidence is available for fatty liver disease. We examined the association of neck circumference with fatty liver disease and evaluated its predictive value in Chinese adults. Methods This cross-sectional study comprised 4053 participants (1617 women and 2436 men, aged 20-88) recruited from the Health Examination Center in Guangzhou, China between May 2009 and April 2010. Anthropometric measurements were taken, abdominal ultrasonography was conducted and blood biochemical parameters were measured. Covariance, logistic regression and receiver operating characteristic curve analyses were employed. Results The mean neck circumference was greater in subjects with fatty liver disease than those without the disease in both women and men after adjusting for age (P<0.001). Logistic regression analysis showed that the age-adjusted ORs (95% CI) of fatty liver disease for quartile 4 (vs. quartile 1) of neck circumference were 7.70 (4.95-11.99) for women and 12.42 (9.22-16.74) for men. After further adjusting for other anthropometric indices, both individually and combined, the corresponding ORs remained significant (all P-trends<0.05) but were attenuated to 1.94-2.53 for women and 1.45-2.08 for men. An additive interaction existed between neck circumference and the other anthropometric measures (all P<0.05). A high neck circumference value was associated with a much greater prevalence of fatty liver disease in participants with both high and normal BMI, waist circumference and waist-to-hip ratio values. Conclusions Neck circumference was an independent predictor for fatty liver disease and provided an additional contribution when applied with other anthropometric measures. PMID:25679378

  18. Neurons within the same network independently achieve conserved output by differentially balancing variable conductance magnitudes.

    PubMed

    Ransdell, Joseph L; Nair, Satish S; Schulz, David J

    2013-06-12

    Biological and theoretical evidence suggest that individual neurons may achieve similar outputs by differentially balancing variable underlying ionic conductances. Despite the substantial amount of data consistent with this idea, a direct biological demonstration that cells with conserved output, particularly within the same network, achieve these outputs via different solutions has been difficult to achieve. Here we demonstrate definitively that neurons from native neural networks with highly similar output achieve this conserved output by differentially tuning underlying conductance magnitudes. Multiple motor neurons of the crab (Cancer borealis) cardiac ganglion have highly conserved output within a preparation, despite showing a 2-4-fold range of conductance magnitudes. By blocking subsets of these currents, we demonstrate that the remaining conductances become unbalanced, causing disparate output as a result. Therefore, as strategies to understand neuronal excitability become increasingly sophisticated, it is important that such variability in excitability of neurons, even among those within the same individual, is taken into account. PMID:23761890

  19. The probability distribution function for the sum of squares of independent random variables

    NASA Astrophysics Data System (ADS)

    Fateev, Yury; Dmitriev, Dmitry; Tyapkin, Valery; Kremez, Nikolai; Shaidurov, Vladimir

    2016-08-01

    In the present paper, the probability distribution function is derived for the sum of squares of random variables for nonzero expectations. This distribution function enables one to develop an efficient one-step algorithm for phase ambiguity resolution when determining the spatial orientation from signals of satellite radio-navigation systems. Threshold values for rejecting false solutions and statistical properties of the algorithm are obtained.

  20. A new noninferiority test for independent dichotomous variables based on a shrinkage proportion estimator.

    PubMed

    Almendra-Arao, Félix

    2015-01-01

    A new noninferiority test for the difference between two independent proportions is presented. The test is based on a Wald-type statistic in which maximum likelihood estimators and a type of shrinkage estimator are used to estimate proportions. This new test was compared with another Wald-type test that has been shown to behave well in terms of test size and power. For the comparison, the behavior of the new test, in terms of its size and power, was analyzed over several configurations. While the two tests exhibited similar behavior, the new test is easier to implement and thus constitutes a practical alternative.

  1. Spatio-temporal variability of droughts and terrestrial water storage over Lake Chad Basin using independent component analysis

    NASA Astrophysics Data System (ADS)

    Ndehedehe, Christopher E.; Agutu, Nathan O.; Okwuashi, Onuwa; Ferreira, Vagner G.

    2016-09-01

    Lake Chad has recently been perceived to be completely desiccated and almost extinct due to insufficient published ground observations. Given the high spatial variability of rainfall in the region, and the fact that extreme climatic conditions (for example, droughts) could be intensifying in the Lake Chad basin (LCB) due to human activities, a spatio-temporal approach to drought analysis becomes essential. This study employed independent component analysis (ICA), a fourth-order cumulant statistics, to decompose standardised precipitation index (SPI), standardised soil moisture index (SSI), and terrestrial water storage (TWS) derived from Gravity Recovery and Climate Experiment (GRACE) into spatial and temporal patterns over the LCB. In addition, this study uses satellite altimetry data to estimate variations in the Lake Chad water levels, and further employs relevant climate teleconnection indices (El-Niño Southern Oscillation-ENSO, Atlantic Multi-decadal Oscillation-AMO, and Atlantic Meridional Mode-AMM) to examine their links to the observed drought temporal patterns over the basin. From the spatio-temporal drought analysis, temporal evolutions of SPI at 12 month aggregation show relatively wet conditions in the last two decades (although with marked alterations) with the 2012-2014 period being the wettest. In addition to the improved rainfall conditions during this period, there was a statistically significant increase of 0.04 m/yr in altimetry water levels observed over Lake Chad between 2008 and 2014, which confirms a shift in the hydrological conditions of the basin. Observed trend in TWS changes during the 2002-2014 period shows a statistically insignificant increase of 3.0 mm/yr at the centre of the basin, coinciding with soil moisture deficit indicated by the temporal evolutions of SSI at all monthly accumulations during the 2002-2003 and 2009-2012 periods. Further, SPI at 3 and 6 month scales indicated fluctuating drought conditions at the extreme south

  2. Implementation of continuous-variable quantum key distribution with composable and one-sided-device-independent security against coherent attacks.

    PubMed

    Gehring, Tobias; Händchen, Vitus; Duhme, Jörg; Furrer, Fabian; Franz, Torsten; Pacher, Christoph; Werner, Reinhard F; Schnabel, Roman

    2015-01-01

    Secret communication over public channels is one of the central pillars of a modern information society. Using quantum key distribution this is achieved without relying on the hardness of mathematical problems, which might be compromised by improved algorithms or by future quantum computers. State-of-the-art quantum key distribution requires composable security against coherent attacks for a finite number of distributed quantum states as well as robustness against implementation side channels. Here we present an implementation of continuous-variable quantum key distribution satisfying these requirements. Our implementation is based on the distribution of continuous-variable Einstein-Podolsky-Rosen entangled light. It is one-sided device independent, which means the security of the generated key is independent of any memoryfree attacks on the remote detector. Since continuous-variable encoding is compatible with conventional optical communication technology, our work is a step towards practical implementations of quantum key distribution with state-of-the-art security based solely on telecom components. PMID:26514280

  3. Implementation of continuous-variable quantum key distribution with composable and one-sided-device-independent security against coherent attacks

    NASA Astrophysics Data System (ADS)

    Gehring, Tobias; Händchen, Vitus; Duhme, Jörg; Furrer, Fabian; Franz, Torsten; Pacher, Christoph; Werner, Reinhard F.; Schnabel, Roman

    2015-10-01

    Secret communication over public channels is one of the central pillars of a modern information society. Using quantum key distribution this is achieved without relying on the hardness of mathematical problems, which might be compromised by improved algorithms or by future quantum computers. State-of-the-art quantum key distribution requires composable security against coherent attacks for a finite number of distributed quantum states as well as robustness against implementation side channels. Here we present an implementation of continuous-variable quantum key distribution satisfying these requirements. Our implementation is based on the distribution of continuous-variable Einstein-Podolsky-Rosen entangled light. It is one-sided device independent, which means the security of the generated key is independent of any memoryfree attacks on the remote detector. Since continuous-variable encoding is compatible with conventional optical communication technology, our work is a step towards practical implementations of quantum key distribution with state-of-the-art security based solely on telecom components.

  4. Implementation of continuous-variable quantum key distribution with composable and one-sided-device-independent security against coherent attacks

    PubMed Central

    Gehring, Tobias; Händchen, Vitus; Duhme, Jörg; Furrer, Fabian; Franz, Torsten; Pacher, Christoph; Werner, Reinhard F.; Schnabel, Roman

    2015-01-01

    Secret communication over public channels is one of the central pillars of a modern information society. Using quantum key distribution this is achieved without relying on the hardness of mathematical problems, which might be compromised by improved algorithms or by future quantum computers. State-of-the-art quantum key distribution requires composable security against coherent attacks for a finite number of distributed quantum states as well as robustness against implementation side channels. Here we present an implementation of continuous-variable quantum key distribution satisfying these requirements. Our implementation is based on the distribution of continuous-variable Einstein–Podolsky–Rosen entangled light. It is one-sided device independent, which means the security of the generated key is independent of any memoryfree attacks on the remote detector. Since continuous-variable encoding is compatible with conventional optical communication technology, our work is a step towards practical implementations of quantum key distribution with state-of-the-art security based solely on telecom components. PMID:26514280

  5. Implementation of continuous-variable quantum key distribution with composable and one-sided-device-independent security against coherent attacks.

    PubMed

    Gehring, Tobias; Händchen, Vitus; Duhme, Jörg; Furrer, Fabian; Franz, Torsten; Pacher, Christoph; Werner, Reinhard F; Schnabel, Roman

    2015-10-30

    Secret communication over public channels is one of the central pillars of a modern information society. Using quantum key distribution this is achieved without relying on the hardness of mathematical problems, which might be compromised by improved algorithms or by future quantum computers. State-of-the-art quantum key distribution requires composable security against coherent attacks for a finite number of distributed quantum states as well as robustness against implementation side channels. Here we present an implementation of continuous-variable quantum key distribution satisfying these requirements. Our implementation is based on the distribution of continuous-variable Einstein-Podolsky-Rosen entangled light. It is one-sided device independent, which means the security of the generated key is independent of any memoryfree attacks on the remote detector. Since continuous-variable encoding is compatible with conventional optical communication technology, our work is a step towards practical implementations of quantum key distribution with state-of-the-art security based solely on telecom components.

  6. Analysis of imaging properties of active lenses with spherical surfaces of independently variable curvature

    NASA Astrophysics Data System (ADS)

    Pokorný, Petr; Novák, Jiří; Novák, Pavel; Mikš, Antonín.

    2014-12-01

    This work presents an algebraic analysis and computer simulations of imaging properties of a refractive tunable-focus fluidic lens with two continuously variable radii of curvature. Such lenses make possible to change aberration properties. It is shown that such a tunable-focus lens makes possible to correct simultaneously its spherical aberration and coma, which is not possible with the conventional fix-focus lens. Formulas are derived for the calculation of paraxial parameters and Seidel aberration coefficients of the lens. Imaging properties are demonstrated on several examples.

  7. Independently variable phase and stroke control for a double acting Stirling engine

    DOEpatents

    Berchowitz, David M.

    1983-01-01

    A phase and stroke control apparatus for the pistons of a Stirling engine includes a ring on the end of each piston rod in which a pair of eccentrics is arranged in series, torque transmitting relationship. The outer eccentric is rotatably mounted in the ring and is rotated by the orbiting ring; the inner eccentric is mounted on an output shaft. The two eccentrics are mounted for rotation together within the ring during normal operation. A device is provided for rotating one eccentric with respect to another to change the effective eccentricity of the pair of eccentrics. A separately controlled phase adjustment is provided to null the phase change introduced by the change in the orientation of the outer eccentric, and also to enable the phase of the pistons to be changed independently of the stroke change.

  8. The biobehavioral family model: testing social support as an additional exogenous variable.

    PubMed

    Woods, Sarah B; Priest, Jacob B; Roush, Tara

    2014-12-01

    This study tests the inclusion of social support as a distinct exogenous variable in the Biobehavioral Family Model (BBFM). The BBFM is a biopsychosocial approach to health that proposes that biobehavioral reactivity (anxiety and depression) mediates the relationship between family emotional climate and disease activity. Data for this study included married, English-speaking adult participants (n = 1,321; 55% female; M age = 45.2 years) from the National Comorbidity Survey Replication, a nationally representative epidemiological study of the frequency of mental disorders in the United States. Participants reported their demographics, marital functioning, social support from friends and relatives, anxiety and depression (biobehavioral reactivity), number of chronic health conditions, and number of prescription medications. Confirmatory factor analyses supported the items used in the measures of negative marital interactions, social support, and biobehavioral reactivity, as well as the use of negative marital interactions, friends' social support, and relatives' social support as distinct factors in the model. Structural equation modeling indicated a good fit of the data to the hypothesized model (χ(2)  = 846.04, p = .000, SRMR = .039, CFI = .924, TLI = .914, RMSEA = .043). Negative marital interactions predicted biobehavioral reactivity (β = .38, p < .001), as did relatives' social support, inversely (β = -.16, p < .001). Biobehavioral reactivity predicted disease activity (β = .40, p < .001) and was demonstrated to be a significant mediator through tests of indirect effects. Findings are consistent with previous tests of the BBFM with adult samples, and suggest the important addition of family social support as a predicting factor in the model. PMID:24981970

  9. The biobehavioral family model: testing social support as an additional exogenous variable.

    PubMed

    Woods, Sarah B; Priest, Jacob B; Roush, Tara

    2014-12-01

    This study tests the inclusion of social support as a distinct exogenous variable in the Biobehavioral Family Model (BBFM). The BBFM is a biopsychosocial approach to health that proposes that biobehavioral reactivity (anxiety and depression) mediates the relationship between family emotional climate and disease activity. Data for this study included married, English-speaking adult participants (n = 1,321; 55% female; M age = 45.2 years) from the National Comorbidity Survey Replication, a nationally representative epidemiological study of the frequency of mental disorders in the United States. Participants reported their demographics, marital functioning, social support from friends and relatives, anxiety and depression (biobehavioral reactivity), number of chronic health conditions, and number of prescription medications. Confirmatory factor analyses supported the items used in the measures of negative marital interactions, social support, and biobehavioral reactivity, as well as the use of negative marital interactions, friends' social support, and relatives' social support as distinct factors in the model. Structural equation modeling indicated a good fit of the data to the hypothesized model (χ(2)  = 846.04, p = .000, SRMR = .039, CFI = .924, TLI = .914, RMSEA = .043). Negative marital interactions predicted biobehavioral reactivity (β = .38, p < .001), as did relatives' social support, inversely (β = -.16, p < .001). Biobehavioral reactivity predicted disease activity (β = .40, p < .001) and was demonstrated to be a significant mediator through tests of indirect effects. Findings are consistent with previous tests of the BBFM with adult samples, and suggest the important addition of family social support as a predicting factor in the model.

  10. The temperature size rule in arthropods: independent of macro-environmental variables but size dependent.

    PubMed

    Klok, C Jaco; Harrison, Jon F

    2013-10-01

    Temperature is a key factor that affects the rates of growth and development in animals, which ultimately determine body size. Although not universal, a widely documented and poorly understood pattern is the inverse relationship between the temperature at which an ectothermic animal is reared and its body size (temperature size rule [TSR]). The proximate and ultimate mechanisms for the TSR remain unclear. To explore possible explanations for the TSR, we tested for correlations between the magnitude/direction of the TSR and latitude, temperature, elevation, habitat, availability of oxygen, capacity for flight, and taxonomic grouping in 98 species/populations of arthropods. The magnitude and direction of the TSR was not correlated with any of the macro-environmental variables we examined, supporting the generality of the TSR. However, body size affected the magnitude and direction of the TSR, with smaller arthropods more likely to demonstrate a classic TSR. Considerable variation among species exists in the TSR, suggesting either strong interactions with nutrition, or selection based on microclimatic or seasonal variation not captured in classic macro-environmental variables.

  11. Intra-Gene DNA Methylation Variability Is a Clinically Independent Prognostic Marker in Women’s Cancers

    PubMed Central

    Bartlett, Thomas E.; Jones, Allison; Goode, Ellen L.; Fridley, Brooke L.; Cunningham, Julie M.; Berns, Els M. J. J.; Wik, Elisabeth; Salvesen, Helga B.; Davidson, Ben; Trope, Claes G.; Lambrechts, Sandrina; Vergote, Ignace; Widschwendter, Martin

    2015-01-01

    We introduce a novel per-gene measure of intra-gene DNA methylation variability (IGV) based on the Illumina Infinium HumanMethylation450 platform, which is prognostic independently of well-known predictors of clinical outcome. Using IGV, we derive a robust gene-panel prognostic signature for ovarian cancer (OC, n = 221), which validates in two independent data sets from Mayo Clinic (n = 198) and TCGA (n = 358), with significance of p = 0.004 in both sets. The OC prognostic signature gene-panel is comprised of four gene groups, which represent distinct biological processes. We show the IGV measurements of these gene groups are most likely a reflection of a mixture of intra-tumour heterogeneity and transcription factor (TF) binding/activity. IGV can be used to predict clinical outcome in patients individually, providing a surrogate read-out of hard-to-measure disease processes. PMID:26629914

  12. FIT: Computer Program that Interactively Determines Polynomial Equations for Data which are a Function of Two Independent Variables

    NASA Technical Reports Server (NTRS)

    Arbuckle, P. D.; Sliwa, S. M.; Roy, M. L.; Tiffany, S. H.

    1985-01-01

    A computer program for interactively developing least-squares polynomial equations to fit user-supplied data is described. The program is characterized by the ability to compute the polynomial equations of a surface fit through data that are a function of two independent variables. The program utilizes the Langley Research Center graphics packages to display polynomial equation curves and data points, facilitating a qualitative evaluation of the effectiveness of the fit. An explanation of the fundamental principles and features of the program, as well as sample input and corresponding output, are included.

  13. Influence of independent and proximate variables on condom use in selected states in Nigeria.

    PubMed

    Akinyemi, A I; Aransiola, J O; Banjo, O; Bamiwuye, O; Fadeyibi, O; Adewuyi, A

    2010-12-01

    The study examined the influence of individual and proximate factors in determining condom use. Current use of condom and condom use during last sex were used as proxies for consistent condom use. Data on 3,797 sexually active respondents of reproductive age were analyzed from the 2007 USAID-COMPASS midline evaluation on basic family planning and reproductive health outcomes in five Nigerian states. About 9% of respondents were current users, while 11% used a condom during last sex. Younger and more educated respondents were more likely to report condom use. Of the 23 variables, four were statistically significant (p < 0.05) in predicting current use for females, and five for males; six were statistically significant in predicting condom use during last sex for females and seven for males. The paper concluded that understanding the determinants and predictors of condom use is critical to improving family planning and reproductive health indicators in Nigeria.

  14. Assessment of the effects of physical training in patients with chronic heart failure: the utility of effort-independent exercise variables.

    PubMed

    Kemps, Hareld M C; de Vries, Wouter R; Schmikli, Sandor L; Zonderland, Maria L; Hoogeveen, Adwin R; Thijssen, Eric J M; Schep, Goof

    2010-02-01

    Traditionally, the effects of physical training in patients with chronic heart failure (CHF) are evaluated by changes in peak oxygen uptake (peak VO(2)). The assessment of peak VO(2), however, is highly dependent on the patients' motivation. The aim of the present study was to evaluate the clinical utility of effort-independent exercise variables for detecting training effects in CHF patients. In a prospective controlled trial, patients with stable CHF were allocated to an intervention group (N = 30), performing a 12-week combined cycle interval and muscle resistance training program, or a control group (N = 18) that was matched for age, gender, body composition and left ventricular ejection fraction. The following effort-independent exercise variables were evaluated: the ventilatory anaerobic threshold (VAT), oxygen uptake efficiency slope (OUES), the V(E)/VCO(2) slope and the time constant of VO(2) kinetics during recovery from submaximal constant-load exercise (tau-rec). In addition to post-training increases in peak VO(2) and peak V(E), the intervention group showed significant within and between-group improvements in VAT, OUES and tau-rec. There were no significant differences between relative improvements of the effort-independent exercise variables in the intervention group. In contrast with VAT, which could not be determined in 9% of the patients, OUES and tau-rec were determined successfully in all patients. Therefore, we conclude that OUES and tau-rec are useful in clinical practice for the assessment of training effects in CHF patients, especially in cases of poor subject effort during symptom-limited exercise testing or when patients are unable to reach a maximal exercise level.

  15. ADF95: Tool for automatic differentiation of a FORTRAN code designed for large numbers of independent variables

    NASA Astrophysics Data System (ADS)

    Straka, Christian W.

    2005-06-01

    ADF95 is a tool to automatically calculate numerical first derivatives for any mathematical expression as a function of user defined independent variables. Accuracy of derivatives is achieved within machine precision. ADF95 may be applied to any FORTRAN 77/90/95 conforming code and requires minimal changes by the user. It provides a new derived data type that holds the value and derivatives and applies forward differencing by overloading all FORTRAN operators and intrinsic functions. An efficient indexing technique leads to a reduced memory usage and a substantially increased performance gain over other available tools with operator overloading. This gain is especially pronounced for sparse systems with large number of independent variables. A wide class of numerical simulations, e.g., those employing implicit solvers, can profit from ADF95. Program summaryTitle of program:ADF95 Catalogue identifier: ADVI Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADVI Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Computer for which the program is designed: all platforms with a FORTRAN 95 compiler Programming language used:FORTRAN 95 No. of lines in distributed program, including test data, etc.: 3103 No. of bytes in distributed program, including test data, etc.: 9862 Distribution format: tar.gz Nature of problem: In many areas in the computational sciences first order partial derivatives for large and complex sets of equations are needed with machine precision accuracy. For example, any implicit or semi-implicit solver requires the computation of the Jacobian matrix, which contains the first derivatives with respect to the independent variables. ADF95 is a software module to facilitate the automatic computation of the first partial derivatives of any arbitrarily complex mathematical FORTRAN expression. The program exploits the sparsity inherited by many set of equations thereby enabling faster computations compared to alternate

  16. Phytosterol intake and dietary fat reduction are independent and additive in their ability to reduce plasma LDL cholesterol

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The plasma LDL-cholesterol-lowering effect of plant sterols (PS) appears to be independent of background diet, but definitive proof is lacking. The effect of background diet on plasma concentrations of PS has not been reported. We determined the effects of manipulating dietary contents of PS and f...

  17. Addition of simultaneous heat and solute transport and variable fluid viscosity to SEAWAT

    USGS Publications Warehouse

    Thorne, D.; Langevin, C.D.; Sukop, M.C.

    2006-01-01

    SEAWAT is a finite-difference computer code designed to simulate coupled variable-density ground water flow and solute transport. This paper describes a new version of SEAWAT that adds the ability to simultaneously model energy and solute transport. This is necessary for simulating the transport of heat and salinity in coastal aquifers for example. This work extends the equation of state for fluid density to vary as a function of temperature and/or solute concentration. The program has also been modified to represent the effects of variable fluid viscosity as a function of temperature and/or concentration. The viscosity mechanism is verified against an analytical solution, and a test of temperature-dependent viscosity is provided. Finally, the classic Henry-Hilleke problem is solved with the new code. ?? 2006 Elsevier Ltd. All rights reserved.

  18. Separation of the low-frequency atmospheric variability into non-Gaussian multidimensional sources by Independent Subspace Analysis

    NASA Astrophysics Data System (ADS)

    Pires, Carlos; Ribeiro, Andreia

    2016-04-01

    An efficient nonlinear method of statistical source separation of space-distributed non-Gaussian distributed data is proposed. The method relies in the so called Independent Subspace Analysis (ISA), being tested on a long time-series of the stream-function field of an atmospheric quasi-geostrophic 3-level model (QG3) simulating the winter's monthly variability of the Northern Hemisphere. ISA generalizes the Independent Component Analysis (ICA) by looking for multidimensional and minimally dependent, uncorrelated and non-Gaussian distributed statistical sources among the rotated projections or subspaces of the multivariate probability distribution of the leading principal components of the working field whereas ICA restrict to scalar sources. The rationale of that technique relies upon the projection pursuit technique, looking for data projections of enhanced interest. In order to accomplish the decomposition, we maximize measures of the sources' non-Gaussianity by contrast functions which are given by squares of nonlinear, cross-cumulant-based correlations involving the variables spanning the sources. Therefore sources are sought matching certain nonlinear data structures. The maximized contrast function is built in such a way that it provides the minimization of the mean square of the residuals of certain nonlinear regressions. The issuing residuals, followed by spherization, provide a new set of nonlinear variable changes that are at once uncorrelated, quasi-independent and quasi-Gaussian, representing an advantage with respect to the Independent Components (scalar sources) obtained by ICA where the non-Gaussianity is concentrated into the non-Gaussian scalar sources. The new scalar sources obtained by the above process encompass the attractor's curvature thus providing improved nonlinear model indices of the low-frequency atmospheric variability which is useful since large circulation indices are nonlinearly correlated. The non-Gaussian tested sources (dyads and

  19. The theory of planned behaviour and healthy eating: Examining additive and moderating effects of social influence variables.

    PubMed

    Povey, R; Conner, M; Sparks, P; James, R; Shepherd, R

    2000-11-01

    Abstract This paper examines the additive and moderating effects of social influence variables (injunctive norms, descriptive norms, perceived social support) within the Theory of Planned Behaviour (TPB). The target behaviour is the decision to eat healthily. Questionnaire responses on components of the TPB, descriptive norms, perceived social support, and subsequent healthy eating were obtained from a prospective sample of 235 members of the general public. Good predictions of intentions (42% of variance explained) and behaviour (15% of variance explained) were found using the Theory of Planned Behaviour. Neither descriptive norms nor perceived social support added to these predictions of intentions over and above the TPB variables. However, perceived social support was found to act as a moderator variable on the relationship between perceived behavioral control and intention, and the relationship between attitude and intention. Implications for exploring the role of social influence variables on decisions concerning health behavioun an discussed.

  20. The theory of planned behaviour and healthy eating: Examining additive and moderating effects of social influence variables.

    PubMed

    Povey, R; Conner, M; Sparks, P; James, R; Shepherd, R

    2000-11-01

    Abstract This paper examines the additive and moderating effects of social influence variables (injunctive norms, descriptive norms, perceived social support) within the Theory of Planned Behaviour (TPB). The target behaviour is the decision to eat healthily. Questionnaire responses on components of the TPB, descriptive norms, perceived social support, and subsequent healthy eating were obtained from a prospective sample of 235 members of the general public. Good predictions of intentions (42% of variance explained) and behaviour (15% of variance explained) were found using the Theory of Planned Behaviour. Neither descriptive norms nor perceived social support added to these predictions of intentions over and above the TPB variables. However, perceived social support was found to act as a moderator variable on the relationship between perceived behavioral control and intention, and the relationship between attitude and intention. Implications for exploring the role of social influence variables on decisions concerning health behavioun an discussed. PMID:22175258

  1. Independent Regulation of Basal Neurotransmitter Release Efficacy by Variable Ca2+ Influx and Bouton Size at Small Central Synapses

    PubMed Central

    Ermolyuk, Yaroslav S.; Alder, Felicity G.; Henneberger, Christian; Rusakov, Dmitri A.; Kullmann, Dimitri M.; Volynski, Kirill E.

    2012-01-01

    The efficacy of action potential evoked neurotransmitter release varies widely even among synapses supplied by the same axon, and the number of release-ready vesicles at each synapse is a major determinant of this heterogeneity. Here we identify a second, equally important, mechanism for release heterogeneity at small hippocampal synapses, the inter-synaptic variation of the exocytosis probability of release-ready vesicles. Using concurrent measurements of vesicular pool sizes, vesicular exocytosis rates, and presynaptic Ca2+ dynamics, in the same small hippocampal boutons, we show that the average fusion probability of release-ready vesicles varies among synapses supplied by the same axon with the size of the spike-evoked Ca2+ concentration transient. We further show that synapses with a high vesicular release probability exhibit a lower Ca2+ cooperativity, arguing that this is a direct consequence of increased Ca2+ influx at the active zone. We conclude that variability of neurotransmitter release under basal conditions at small central synapses is accounted for not only by the number of release-ready vesicles, but also by their fusion probabilities, which are set independently of bouton size by variable spike-evoked presynaptic Ca2+ influx. PMID:23049481

  2. Enhancing quantum entanglement for continuous variables by a coherent superposition of photon subtraction and addition

    SciTech Connect

    Lee, Su-Yong; Kim, Ho-Joon; Ji, Se-Wan; Nha, Hyunchul

    2011-07-15

    We investigate how the entanglement properties of a two-mode state can be improved by performing a coherent superposition operation ta+ra{sup {dagger}} of photon subtraction and addition, proposed by Lee and Nha [Phys. Rev. A 82, 053812 (2010)], on each mode. We show that the degree of entanglement, the Einstein-Podolsky-Rosen-type correlation, and the performance of quantum teleportation can be all enhanced for the output state when the coherent operation is applied to a two-mode squeezed state. The effects of the coherent operation are more prominent than those of the mere photon subtraction a and the addition a{sup {dagger}} particularly in the small-squeezing regime, whereas the optimal operation becomes the photon subtraction (case of r=0) in the large-squeezing regime.

  3. Spatially variable synergistic effects of disturbance and additional nutrients on kelp recruitment and recovery.

    PubMed

    Carnell, Paul E; Keough, Michael J

    2014-05-01

    Understanding the impact of multiple stressors on ecosystems is of pronounced importance, particularly when one or more of those stressors is anthropogenic. Here we investigated the role of physical disturbance and increased nutrients on reefs dominated by the canopy-forming kelp Ecklonia radiata. We combined experimental kelp canopy removals and additional nutrient at three different locations in a large embayment in temperate southeastern Australia. Over the following winter recruitment season, Ecklonia recruitment was unaffected by increased nutrients alone, but tripled at all sites where the canopy had been removed. At one site, the combination of disturbance and increased nutrients resulted in more than four times the recruitment of the introduced kelp Undaria pinnatifida. Six months after disturbance, the proliferation of the Undaria canopy in the canopy-removal and nutrient-addition treatment negatively influenced the recovery of the native kelp Ecklonia. Given the otherwise competitive dominance of adult Ecklonia, this provides a mechanism whereby Undaria could maintain open space for the following recruitment season. This interplay between disturbance, nutrients and the response of native and invasive species makes a compelling case for how a combination of factors can influence species dynamics.

  4. Rate independence of material properties and remnant state variables during domain switching by electric field or stress in ferroelectric ceramics at room and high temperatures

    NASA Astrophysics Data System (ADS)

    Ji, Dae Won; Kim, Sang-Joo

    2016-09-01

    Various numbers of electric field or compressive stress pulses with increasing magnitude are applied to a poled lead titanate zirconate rectangular parallelepiped specimen. Changes in linear material properties are estimated from measured responses and plotted versus remnant polarization. The dependence of linear material properties on remnant polarization is shown to be the same independent of the overall rate of domain switching by electric field or stress at room and high temperatures. The evolution path of remnant polarization and strains in the plane of remnant state variables is also found to be equal independent of switching rate at room and high temperatures. Finally, when the values of remnant state variables at high temperature are transformed to those of reference remnant state variables, the evolution path of the reference remnant state variables is compared to be coincident with that of remnant state variables at room temperature, implying the same switching process at different temperatures.

  5. Response additivity: effects of superimposed free reinforcement on a variable-interval baseline.

    PubMed

    Boakes, R A; Halliday, M S; Poli, M

    1975-03-01

    Three experiments examined the effects of superimposing free reinforcement (Free VI 30-sec) on behavior maintained by a response dependent mult VI 2-min VI 2-min schedule of reinforcement. Experiment I used pigeons as subjects, key pecking as the response, and colors of response key as the stimuli associated with the multiple-schedule components. When free reinforcement was added during only one component (Differential condition) a large and highly significant increase in response rate developed in this component. Adding free reinforcement during both components (Nondifferential condition) produced smaller and far less-consistent effects. An entirely different pattern of results was obtained in two subsequent experiments, where similar procedures and reinforcement conditions were used with rats as subjects and bar pressing as the response. In both Experiments II and III, response rates decreased to the stimulus associated with added free reinforcement in the Differential condition. These findings are interpreted as the result of interactions between behavior maintained by response-reinforcer contingencies and behavior maintained by stimulus-reinforcer contingencies. As such, they support the main assumption of an autoshaping theory of behavioral contrast, that additivity of responding generated by the two kinds of contingency can occur only in situations favorable to autoshaping.

  6. Bayesian adjustment for the misclassification in both dependent and independent variables with application to a breast cancer study.

    PubMed

    Liu, Juxin; Gustafson, Paul; Huo, Dezheng

    2016-10-15

    In this paper, we propose a Bayesian method to address misclassification errors in both independent and dependent variables. Our work is motivated by a study of women who have experienced new breast cancers on two separate occasions. We call both cancers primary, because the second is usually not considered as the result of a metastasis spreading from the first. Hormone receptors (HRs) are important in breast cancer biology, and it is well recognized that the measurement of HR status is subject to errors. This discordance in HR status for two primary breast cancers is of concern and might be an important reason for treatment failure. To sort out the information on true concordance rate from the observed concordance rate, we consider a logistic regression model for the association between the HR status of the two cancers and introduce the misclassification parameters (i.e., sensitivity and specificity) accounting for the misclassification in HR status. The prior distribution for sensitivity and specificity is based on how HR status is actually assessed in laboratory procedures. To account for the nonlinear effect of one error-free covariate, we introduce the B-spline terms in the logistic regression model. Our findings indicate that the true concordance rate of HR status between two primary cancers is greater than the observed value. Copyright © 2016 John Wiley & Sons, Ltd.

  7. Design of experiments with multiple independent variables: a resource management perspective on complete and reduced factorial designs.

    PubMed

    Collins, Linda M; Dziak, John J; Li, Runze

    2009-09-01

    An investigator who plans to conduct an experiment with multiple independent variables must decide whether to use a complete or reduced factorial design. This article advocates a resource management perspective on making this decision, in which the investigator seeks a strategic balance between service to scientific objectives and economy. Considerations in making design decisions include whether research questions are framed as main effects or simple effects; whether and which effects are aliased (confounded) in a particular design; the number of experimental conditions that must be implemented in a particular design and the number of experimental subjects the design requires to maintain the desired level of statistical power; and the costs associated with implementing experimental conditions and obtaining experimental subjects. In this article 4 design options are compared: complete factorial, individual experiments, single factor, and fractional factorial. Complete and fractional factorial designs and single-factor designs are generally more economical than conducting individual experiments on each factor. Although relatively unfamiliar to behavioral scientists, fractional factorial designs merit serious consideration because of their economy and versatility.

  8. Reflecting Solutions of High Order Elliptic Differential Equations in Two Independent Variables Across Analytic Arcs. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Carleton, O.

    1972-01-01

    Consideration is given specifically to sixth order elliptic partial differential equations in two independent real variables x, y such that the coefficients of the highest order terms are real constants. It is assumed that the differential operator has distinct characteristics and that it can be factored as a product of second order operators. By analytically continuing into the complex domain and using the complex characteristic coordinates of the differential equation, it is shown that its solutions, u, may be reflected across analytic arcs on which u satisfies certain analytic boundary conditions. Moreover, a method is given whereby one can determine a region into which the solution is extensible. It is seen that this region of reflection is dependent on the original domain of difinition of the solution, the arc and the coefficients of the highest order terms of the equation and not on any sufficiently small quantities; i.e., the reflection is global in nature. The method employed may be applied to similar differential equations of order 2n.

  9. Identification of novel estrogen receptor (ER) agonists that have additional and complementary anti-cancer activities via ER-independent mechanism.

    PubMed

    Kim, Taelim; Kim, Hye-In; An, Ji-Young; Lee, Jun; Lee, Na-Rae; Heo, Jinyuk; Kim, Ji-Eun; Yu, Jihyun; Lee, Yong Sup; Inn, Kyung-Soo; Kim, Nam-Jung

    2016-04-01

    In this study, a series of bis(4-hydroxy)benzophenone oxime ether derivatives such as 12c, 12e and 12h were identified as novel estrogen receptor (ER) agonists that have additional and complementary anti-proliferative activities via ER-independent mechanism in cancer cells. These compounds are expected to overcome the therapeutic limitation of existing ER agonists such as estradiol and tamoxifen, which have been known to induce the proliferation of cancer cells. PMID:26905830

  10. Testing a Model of the Relationship of Demographic, Affective, and Fitness Variables to Academic Achievement among Non-Science Majors at an Independent University

    NASA Astrophysics Data System (ADS)

    Dutra, Andrew Martin

    The purpose of this study was to determine the relationship of specific attributes of college students to their academic achievement at an independent university in central Florida. Academic achievement was measured as the numeric score on the final exam in a survey-of-science course (EDS 1032) required for non-science majors. Attribute sets included personological, affective, and fitness variables. A hypothesized diagram of the direct and indirect effects among these attributes relative to academic achievement was developed and tested using data collected Spring 2014 from 168 students in four sections of EDS 1032 at Florida Institute of Technology. Multiple regression results revealed that 19% of the variance in a students' academic achievement was due to the influence of these three sets of research factors; this was found to be statistically significant. The results of mediation analyses also indicated that three variables had significant direct effects on academic achievement, namely gender, number of academic credits, and sports motivation. In addition, gender had a significant indirect effect on academic achievement via stress, and the number of academic credits had a significant indirect effect on academic achievement via sports motivation. These findings indicated that female students scored roughly six points higher than male students on this final exam. Also, gender's influence on academic achievement was partially attributable to the student's level of stress (e.g., male students with high levels of stress had lower grades on this final exam than female students with the same level of stress). In addition, it was found that students taking more academic credits were likely to score higher on this final exam than those students taking fewer credits. Further, as students' level of sports amotivation increased, the strength of the relationship between the number of student academic credits and academic achievement decreased. These results support Self

  11. Complementary Aerodynamic Performance Datasets for Variable Speed Power Turbine Blade Section from Two Independent Transonic Turbine Cascades

    NASA Technical Reports Server (NTRS)

    Flegel, Ashlie B.; Welch, Gerard E.; Giel, Paul W.; Ames, Forrest E.; Long, Jonathan A.

    2015-01-01

    Two independent experimental studies were conducted in linear cascades on a scaled, two-dimensional mid-span section of a representative Variable Speed Power Turbine (VSPT) blade. The purpose of these studies was to assess the aerodynamic performance of the VSPT blade over large Reynolds number and incidence angle ranges. The influence of inlet turbulence intensity was also investigated. The tests were carried out in the NASA Glenn Research Center Transonic Turbine Blade Cascade Facility and at the University of North Dakota (UND) High Speed Compressible Flow Wind Tunnel Facility. A large database was developed by acquiring total pressure and exit angle surveys and blade loading data for ten incidence angles ranging from +15.8deg to -51.0deg. Data were acquired over six flow conditions with exit isentropic Reynolds number ranging from 0.05×106 to 2.12×106 and at exit Mach numbers of 0.72 (design) and 0.35. Flow conditions were examined within the respective facility constraints. The survey data were integrated to determine average exit total-pressure and flow angle. UND also acquired blade surface heat transfer data at two flow conditions across the entire incidence angle range aimed at quantifying transitional flow behavior on the blade. Comparisons of the aerodynamic datasets were made for three "match point" conditions. The blade loading data at the match point conditions show good agreement between the facilities. This report shows comparisons of other data and highlights the unique contributions of the two facilities. The datasets are being used to advance understanding of the aerodynamic challenges associated with maintaining efficient power turbine operation over a wide shaft-speed range.

  12. Independent vector analysis based on overlapped cliques of variable width for frequency-domain blind signal separation

    NASA Astrophysics Data System (ADS)

    Lee, Intae; Jang, Gil-Jin

    2012-12-01

    A novel method is proposed to improve the performance of independent vector analysis (IVA) for blind signal separation of acoustic mixtures. IVA is a frequency-domain approach that successfully resolves the well-known permutation problem by applying a spherical dependency model to all pairs of frequency bins. The dependency model of IVA is equivalent to a single clique in an undirected graph; a clique in graph theory is defined as a subset of vertices in which any pair of vertices is connected by an undirected edge. Therefore, IVA imposes the same amount of statistical dependency on every pair of frequency bins, which may not match the characteristics of real-world signals. The proposed method allows variable amounts of statistical dependencies according to the correlation coefficients observed in real acoustic signals and, hence, enables more accurate modeling of statistical dependencies. A number of cliques constitutes the new dependency graph so that neighboring frequency bins are assigned to the same clique, while distant bins are assigned to different cliques. The permutation ambiguity is resolved by overlapped frequency bins between neighboring cliques. For speech signals, we observed especially strong correlations across neighboring frequency bins and a decrease in these correlations with an increase in the distance between bins. The clique sizes are either fixed, or determined by the reciprocal of the mel-frequency scale to impose a wider dependency on low-frequency components. Experimental results showed improved performances over conventional IVA. The signal-to-interference ratio improved from 15.5 to 18.8 dB on average for seven different source locations. When we varied the clique sizes according to the observed correlations, the stability of the proposed method increased with a large number of cliques.

  13. Variability in Ozone in the Tropical Tropopause Region from the 1998-2000 SHADOZ (Southern Hemisphere ADditional OZonesondes) Data

    NASA Technical Reports Server (NTRS)

    Thompson, Anne M.; Witte, J. C.; Oltmans, S. J.; Schmidlin, F. J.

    2002-01-01

    The first view of stratospheric and tropospheric ozone variability in the southern hemisphere tropics is provided by a 3-year, 10-site record of ozone soundings from the Southern Hemisphere ADditional OZonesondes (SHADOZ) network. Observations covering 1998-2000 were made over Ascension Island; Nairobi, Kenya; Irene, South Africa; Reunion Island; Watukosek, Java; Fiji; Tahiti; American Samoa; San Cristobal, Galapagos; Natal, Brazil. Taking the TTL (tropical tropopause layer) as the region between 12 and 17 km, we examine ozone variability in this region on a week-to-week and seasonal basis. The TTL layer is lower in September-October-November than in March-April-May, when ozone is a minimum at most SHADOZ stations. A zonal wave-one pattern is apparent in column-integrated TTL ozone because ozone mixing ratios are greater over the Atlantic and adjacent continents than over the Pacific and eastern Indian Ocean. The wave-one persists all year with varying magnitude and appears to be due to general circulation - with subsidence over the Atlantic and frequent deep convection over the Pacific and Indian Ocean. The variability of deep convection - most prominent at Java, Fiji, Samoa and Natal - is explored in time-vs-altitude ozone curtains. Stratospheric incursions into the troposphere are most prominent in soundings at Irene and Reunion Island.

  14. Variability in Ozone in the Tropical Tropopause Region from the 1998-2000 SHADOZ (Southern Hemisphere ADditional OZonesondes) Data

    NASA Astrophysics Data System (ADS)

    Thompson, A. M.; Witte, J. C.; Oltmans, S. J.; Schmidlin, F. J.

    2002-05-01

    The first view of stratospheric and tropospheric ozone variability in the southern hemisphere tropics is provided by a 3-year, 10-site record of ozone soundings from the Southern Hemisphere ADditional OZonesondes (SHADOZ) network: (http://code916.gsfc.nasa.gov/Data_services/shadoz). Observations covering 1998-2000 were made over Ascension Island; Nairobi, Kenya; Irene, South Africa; Réunion Island; Watukosek, Java; Fiji; Tahiti; American Samoa; San Cristóbal, Galapagos; Natal, Brazil. Taking the TTL (tropical tropopause layer) as the region between 12 and 17 km, we examine ozone variability in this region on a week-to-week and seasonal basis. The TTL layer is lower in September-October-November than in March-April-May, when ozone is a minimum at most SHADOZ stations. A zonal wave-one pattern is apparent in column-integrated TTL ozone because ozone mixing ratios are greater over the Atlantic and adjacent continents than over the Pacific and eastern Indian Ocean. The wave-one persists all year with varying magnitude and appears to be due to general circulation - with subsidence over the Atlantic and frequent deep convection over the Pacific and Indian Ocean. The variability of deep convection - most prominent at Java, Fiji, Samoa and Natal - is explored in time-vs-altitude ozone curtains. Stratospheric incursions into the troposphere are most prominent in soundings at Irene and Réunion Island.

  15. An analysis of input errors in precipitation- runoff models using regression with errors in the independent variables ( Turtle Creek, Dallas, Texas).

    USGS Publications Warehouse

    Troutman, B.M.

    1982-01-01

    Errors in runoff prediction caused by input data errors are analyzed by treating precipitation-runoff models as regression (conditional expectation) models. Independent variables of the regression consist of precipitation and other input measurements; the dependent variable is runoff. In models using erroneous input data, prediction errors are inflated and estimates of expected storm runoff for given observed input variables are biased. A case study using a set of data from Turtle Creek near Dallas, Texas illustrates the problems of model input errors. -from Author

  16. AN INDEPENDENT ANALYSIS OF THE BROWN DWARF ATMOSPHERE MONITORING (BAM) DATA: LARGE-AMPLITUDE VARIABILITY IS RARE OUTSIDE THE L/T TRANSITION

    SciTech Connect

    Radigan, Jacqueline

    2014-12-20

    Observations of variability can provide valuable information about the processes of cloud formation and dissipation in brown dwarf atmospheres. Here we report the results of an independent analysis of archival data from the Brown dwarf Atmosphere Monitoring (BAM) program. Time series data for 14 L and T dwarfs reported to be significantly variable over timescales of hours were analyzed. We confirm large-amplitude variability (amplitudes >2%) for 4 out of 13 targets and place upper limits of 0.7%-1.6% on variability in the remaining sample. For two targets we find evidence of weak variability at amplitudes of 1.3% and 1.6%. Based on our revised classification of variable objects in the BAM study, we find strong variability outside the L/T transition to be rare at near infrared wavelengths. From a combined sample of 81 L0-T9 dwarfs from the revised BAM sample and the variability survey of Radigan et al., we infer an overall observed frequency for large-amplitude variability outside the L/T transition of 3.2{sub −1.8}{sup +2.8}%, in contrast to 24{sub −9}{sup +11}% for L9-T3.5 spectral types. We conclude that while strong variability is not limited to the L/T transition, it occurs more frequently in this spectral type range, indicative of larger or more highly contrasting cloud features at these spectral types.

  17. Southern Hemisphere Additional Ozonesondes (SHADOZ) 1998-2000 tropical ozone climatology 2. Tropospheric variability and the zonal wave-one

    NASA Astrophysics Data System (ADS)

    Thompson, Anne M.; Witte, Jacquelyn C.; Oltmans, Samuel J.; Schmidlin, Francis J.; Logan, Jennifer A.; Fujiwara, Masatomo; Kirchhoff, Volker W. J. H.; Posny, FrançOise; Coetzee, Gert J. R.; Hoegger, Bruno; Kawakami, Shuji; Ogawa, Toshihiro; Fortuin, J. P. F.; Kelder, H. M.

    2003-01-01

    The first view of stratospheric and tropospheric ozone variability in the Southern Hemisphere tropics is provided by a 3-year record of ozone soundings from the Southern Hemisphere Additional Ozonesondes (SHADOZ) network (http://croc.gsfc.nasa.gov/shadoz). Observations covering 1998-2000 were made over Ascension Island, Nairobi (Kenya), Irene (South Africa), Réunion Island, Watukosek (Java), Fiji, Tahiti, American Samoa, San Cristóbal (Galapagos), and Natal (Brazil). Total, stratospheric, and tropospheric column ozone amounts usually peak between August and November. Other features are a persistent zonal wave-one pattern in total column ozone and signatures of the quasi-biennial oscillation (QBO) in stratospheric ozone. The wave-one is due to a greater concentration of free tropospheric ozone over the tropical Atlantic than the Pacific and appears to be associated with tropical general circulation and seasonal pollution from biomass burning. Tropospheric ozone over the Indian and Pacific Oceans displays influences of the waning 1997-1998 El Niño, seasonal convection, and pollution transport from Africa. The most distinctive feature of SHADOZ tropospheric ozone is variability in the data, e.g., a factor of 3 in column amount at 8 of 10 stations. Seasonal and monthly means may not be robust quantities because statistics are frequently not Gaussian even at sites that are always in tropical air. Models and satellite retrievals should be evaluated on their capability for reproducing tropospheric variability and fine structure. A 1999-2000 ozone record from Paramaribo, Surinam (6°N, 55°W) (also in SHADOZ) shows a marked contrast to southern tropical ozone because Surinam is often north of the Intertropical Convergence Zone (ITCZ). A more representative tropospheric ozone climatology for models and satellite retrievals requires additional Northern Hemisphere tropical data.

  18. Post-lumpectomy CT-guided tumor bed delineation for breast boost and partial breast irradiation: Can additional pre- and postoperative imaging reduce interobserver variability?

    PubMed Central

    DEN HARTOGH, MARISKA D.; PHILIPPENS, MARIELLE E.P.; VAN DAM, IRIS E.; KLEYNEN, CATHARINA E.; TERSTEEG, ROBBERT J.H.A.; KOTTE, ALEXIS N.T.J.; VAN VULPEN, MARCO; VAN ASSELEN, BRAM; VAN DEN BONGARD, DESIRÉE H.J.G.

    2015-01-01

    For breast boost radiotherapy or accelerated partial breast irradiation, the tumor bed (TB) is delineated by the radiation oncologist on a planning computed tomography (CT) scan. The aim of the present study was to investigate whether the interobserver variability (IOV) of the TB delineation is reduced by providing the radiation oncologist with additional magnetic resonance imaging (MRI) or CT scans. A total of 14 T1-T2 breast cancer patients underwent a standard planning CT in the supine treatment position following lumpectomy, as well as additional pre- and postoperative imaging in the same position. Post-lumpectomy TBs were independently delineated by four breast radiation oncologists on standard postoperative CT and on CT registered to an additional imaging modality. The additional imaging modalities used were postoperative MRI, preoperative contrast-enhanced (CE)-CT and preoperative CE-MRI. A cavity visualization score (CVS) was assigned to each standard postoperative CT by each observer. In addition, the conformity index (CI), volume and distance between centers of mass (dCOM) of the TB delineations were calculated. On CT, the median CI was 0.57, with a median volume of 22 cm3 and dCOM of 5.1 mm. The addition of postoperative MRI increased the median TB volume significantly to 28 cm3 (P<0.001), while the CI (P=0.176) and dCOM (P=0.110) were not affected. The addition of preoperative CT or MRI increased the TB volume to 26 and 25 cm3, respectively (both P<0.001), while the CI increased to 0.58 and 0.59 (both P<0.001) and the dCOM decreased to 4.7 mm (P=0.004) and 4.6 mm (P=0.001), respectively. In patients with CVS≤3, the median CI was 0.40 on CT, which was significantly increased by all additional imaging modalities, up to 0.52, and was accompanied by a median volume increase up to 6 cm3. In conclusion, the addition of postoperative MRI, preoperative CE-CT or preoperative CE-MRI did not result in a considerable reduction in the IOV in postoperative CT

  19. THE GJ1214 SUPER-EARTH SYSTEM: STELLAR VARIABILITY, NEW TRANSITS, AND A SEARCH FOR ADDITIONAL PLANETS

    SciTech Connect

    Berta, Zachory K.; Charbonneau, David; Bean, Jacob; Irwin, Jonathan; Burke, Christopher J.; Desert, Jean-Michel; Nutzman, Philip; Falco, Emilio E.

    2011-07-20

    The super-Earth GJ1214b transits a nearby M dwarf that exhibits a 1% intrinsic variability in the near-infrared. Here, we analyze new observations to refine the physical properties of both the star and planet. We present three years of out-of-transit photometric monitoring of the stellar host GJ1214 from the MEarth Observatory and find the rotation period to be long, most likely an integer multiple of 53 days, suggesting low levels of magnetic activity and an old age for the system. We show that such variability will not pose significant problems to ongoing studies of the planet's atmosphere with transmission spectroscopy. We analyze two high-precision transit light curves from ESO's Very Large Telescope (VLT) along with seven others from the MEarth and Fred Lawrence Whipple Observatory 1.2 m telescopes, finding physical parameters for the planet that are consistent with previous work. The VLT light curves show tentative evidence for spot occultations during transit. Using two years of MEarth light curves, we place limits on additional transiting planets around GJ1214 with periods out to the habitable zone of the system. We also improve upon the previous photographic V-band estimate for the star, finding V = 14.71 {+-} 0.03.

  20. Variable Temperature Stress in the Nematode Caenorhabditis elegans (Maupas) and Its Implications for Sensitivity to an Additional Chemical Stressor.

    PubMed

    Cedergreen, Nina; Nørhave, Nils Jakob; Svendsen, Claus; Spurgeon, David J

    2016-01-01

    A wealth of studies has investigated how chemical sensitivity is affected by temperature, however, almost always under different constant rather than more realistic fluctuating regimes. Here we compared how the nematode Caenorhabditis elegans responds to copper at constant temperatures (8-24°C) and under fluctuation conditions of low (±4°C) and high (±8°C) amplitude (averages of 12, 16, 20°C and 16°C respectively). The DEBkiss model was used to interpret effects on energy budgets. Increasing constant temperature from 12-24°C reduced time to first egg, life-span and population growth rates consistent with temperature driven metabolic rate change. Responses at 8°C did not, however, accord with this pattern (including a deviation from the Temperature Size Rule), identifying a cold stress effect. High amplitude variation and low amplitude variation around a mean temperature of 12°C impacted reproduction and body size compared to nematodes kept at the matching average constant temperatures. Copper exposure affected reproduction, body size and life-span and consequently population growth. Sensitivity to copper (EC50 values), was similar at intermediate temperatures (12, 16, 20°C) and higher at 24°C and especially the innately stressful 8°C condition. Temperature variation did not increase copper sensitivity. Indeed under variable conditions including time at the stressful 8°C condition, sensitivity was reduced. DEBkiss identified increased maintenance costs and increased assimilation as possible mechanisms for cold and higher copper concentration effects. Model analysis of combined variable temperature effects, however, demonstrated no additional joint stressor response. Hence, concerns that exposure to temperature fluctuations may sensitise species to co-stressor effects seem unfounded in this case.

  1. Variable Temperature Stress in the Nematode Caenorhabditis elegans (Maupas) and Its Implications for Sensitivity to an Additional Chemical Stressor.

    PubMed

    Cedergreen, Nina; Nørhave, Nils Jakob; Svendsen, Claus; Spurgeon, David J

    2016-01-01

    A wealth of studies has investigated how chemical sensitivity is affected by temperature, however, almost always under different constant rather than more realistic fluctuating regimes. Here we compared how the nematode Caenorhabditis elegans responds to copper at constant temperatures (8-24°C) and under fluctuation conditions of low (±4°C) and high (±8°C) amplitude (averages of 12, 16, 20°C and 16°C respectively). The DEBkiss model was used to interpret effects on energy budgets. Increasing constant temperature from 12-24°C reduced time to first egg, life-span and population growth rates consistent with temperature driven metabolic rate change. Responses at 8°C did not, however, accord with this pattern (including a deviation from the Temperature Size Rule), identifying a cold stress effect. High amplitude variation and low amplitude variation around a mean temperature of 12°C impacted reproduction and body size compared to nematodes kept at the matching average constant temperatures. Copper exposure affected reproduction, body size and life-span and consequently population growth. Sensitivity to copper (EC50 values), was similar at intermediate temperatures (12, 16, 20°C) and higher at 24°C and especially the innately stressful 8°C condition. Temperature variation did not increase copper sensitivity. Indeed under variable conditions including time at the stressful 8°C condition, sensitivity was reduced. DEBkiss identified increased maintenance costs and increased assimilation as possible mechanisms for cold and higher copper concentration effects. Model analysis of combined variable temperature effects, however, demonstrated no additional joint stressor response. Hence, concerns that exposure to temperature fluctuations may sensitise species to co-stressor effects seem unfounded in this case. PMID:26784453

  2. Variable Temperature Stress in the Nematode Caenorhabditis elegans (Maupas) and Its Implications for Sensitivity to an Additional Chemical Stressor

    PubMed Central

    Svendsen, Claus; Spurgeon, David J.

    2016-01-01

    A wealth of studies has investigated how chemical sensitivity is affected by temperature, however, almost always under different constant rather than more realistic fluctuating regimes. Here we compared how the nematode Caenorhabditis elegans responds to copper at constant temperatures (8–24°C) and under fluctuation conditions of low (±4°C) and high (±8°C) amplitude (averages of 12, 16, 20°C and 16°C respectively). The DEBkiss model was used to interpret effects on energy budgets. Increasing constant temperature from 12–24°C reduced time to first egg, life-span and population growth rates consistent with temperature driven metabolic rate change. Responses at 8°C did not, however, accord with this pattern (including a deviation from the Temperature Size Rule), identifying a cold stress effect. High amplitude variation and low amplitude variation around a mean temperature of 12°C impacted reproduction and body size compared to nematodes kept at the matching average constant temperatures. Copper exposure affected reproduction, body size and life-span and consequently population growth. Sensitivity to copper (EC50 values), was similar at intermediate temperatures (12, 16, 20°C) and higher at 24°C and especially the innately stressful 8°C condition. Temperature variation did not increase copper sensitivity. Indeed under variable conditions including time at the stressful 8°C condition, sensitivity was reduced. DEBkiss identified increased maintenance costs and increased assimilation as possible mechanisms for cold and higher copper concentration effects. Model analysis of combined variable temperature effects, however, demonstrated no additional joint stressor response. Hence, concerns that exposure to temperature fluctuations may sensitise species to co-stressor effects seem unfounded in this case. PMID:26784453

  3. Independent Living Long-Term Outcome Variables in Spinal Cord Injury: A Replication of DeJong.

    ERIC Educational Resources Information Center

    Boschen, Kathryn A.; Gargaro, Judith

    1998-01-01

    A study involving 547 individuals with spinal cord injury (SCI) examined the validity of Gerben DeJong's categories of Living Arrangement and Productivity Status to assess overall independent living. Results confirmed the face validity of these categories. A sample of 28 rehabilitation professionals and individuals with SCI validated ranking…

  4. Stable isotopes provide independent support for the use of mesowear variables for inferring diets in African antelopes.

    PubMed

    Louys, Julien; Ditchfield, Peter; Meloro, Carlo; Elton, Sarah; Bishop, Laura C

    2012-11-01

    We examine the relationship between mesowear variables and carbon and nitrogen isotopes in 16 species of African antelope (Mammalia: Bovidae). We show significant differences in carbon and nitrogen isotope values between individuals exhibiting sharp versus round cusps, and high versus low occlusal relief. We show significant correlations between mesowear variables and both carbon and nitrogen isotopes. We find significant correlations between mesowear score and nitrogen, but not carbon isotopes. Finally, we find no significant correlations between hypsodonty index and either isotope examined. Our results provide strong support for the use of mesowear variables in palaeodietary reconstructions of antelopes. Our results further suggest that for the antelopes examined here, mesowear signals are a direct result of diet, while hyposodonty may be the result of phylogenetic legacy.

  5. The Southern Hemisphere Additional Ozonesondes (SHADOZ) 1998-2002 Tropical Ozone Climatology. 3; Instrumentation and Station-to-Station Variability

    NASA Technical Reports Server (NTRS)

    Thompson, Anne M.; Witte, Jacqueline C.; Smit, Herman G. J.; Oltmans, Samuel J.; Johnson, Bryan J.; Kirchhoff, Volker W. J. H.; Schmidlin, Francis J.

    2004-01-01

    Abstract: Since 1998 the Southern Hemisphere ADditional OZonesondes (SHADOZ) project has collected more than 2000 ozone profiles from a dozen tropical and subtropical sites using balloon-borne electrochemical concentration cell (ECC) ozonesondes. The data (with accompanying pressure-temperature-humidity soundings) are archived. Analysis of ozonesonde imprecision within the SHADOZ dataset revealed that variations in ozonesonde technique could lead to station-to-station biases in the measurements. In this paper imprecisions and accuracy in the SHADOZ dataset are examined in light of new data. When SHADOZ total ozone column amounts are compared to version 8 TOMS (2004 release), discrepancies between sonde and satellite datasets decline 1-2 percentage points on average, compared to version 7 TOMS. Variability among stations is evaluated using total ozone normalized to TOMS and results of laboratory tests on ozonesondes (JOSE-2O00, Julich Ozonesonde Intercomparison Experiment). Ozone deviations from a standard instrument in the JOSE flight simulation chamber resemble those of SHADOZ station data relative to a SHADOZ-defined climatological reference. Certain systematic variations in SHADOZ ozone profiles are accounted for by differences in solution composition, data processing and instrument (manufacturer). Instrument bias leads to a greater ozone measurement above 25 km over Nairobi and to lower total column ozone at three Pacific sites compared to other SHADOZ stations at 0-20 deg.S.

  6. STAT4 Associates with SLE Through Two Independent Effects that Correlate with Gene Expression and Act Additively with IRF5 to Increase Risk

    PubMed Central

    Abelson, Anna-Karin; Delgado-Vega, Angélica M.; Kozyrev, Sergey V.; Sánchez, Elena; Velázquez-Cruz, Rafael; Eriksson, Niclas; Wojcik, Jerome; Reddy, Prasad Linga; Lima, Guadalupe; D’Alfonso, Sandra; Migliaresi, Sergio; Baca, Vicente; Orozco, Lorena; Witte, Torsten; Ortego-Centeno, Norberto; Abderrahim, Hadi; Pons-Estel, Bernardo A.; Gutiérrez, Carmen; Suárez, Ana; González-Escribano, Maria Francisca; Martin, Javier; Alarcón-Riquelme, Marta E.

    2013-01-01

    Objectives To confirm and define the genetic association of STAT4 and systemic lupus erythematosus, investigate the possibility of correlations with differential splicing and/or expression levels, and genetic interaction with IRF5. Methods 30 tag SNPs were genotyped in an independent set of Spanish cases and controls. SNPs surviving correction for multiple tests were genotyped in 5 new sets of cases and controls for replication. STAT4 cDNA was analyzed by 5’-RACE PCR and sequencing. Expression levels were measured by quantitative PCR. Results In the fine-mapping, four SNPs were significant after correction for multiple testing, with rs3821236 and rs3024866 as the strongest signals, followed by the previously associated rs7574865, and by rs1467199. Association was replicated in all cohorts. After conditional regression analyses, two major independent signals represented by SNPs rs3821236 and rs7574865, remained significant across the sets. These SNPs belong to separate haplotype blocks. High levels of STAT4 expression correlated with SNPs rs3821236, rs3024866 (both in the same haplotype block) and rs7574865 but not with other SNPs. We also detected transcription of alternative tissue-specific exons 1, indicating presence of tissue-specific promoters of potential importance in the expression of STAT4. No interaction with associated SNPs of IRF5 was observed using regression analysis. Conclusions These data confirm STAT4 as a susceptibility gene for SLE and suggest the presence of at least two functional variants affecting levels of STAT4. Our results also indicate that both genes STAT4 and IRF5 act additively to increase risk for SLE. PMID:19019891

  7. High levels of acute phase proteins and soluble 70 kDa heat shock proteins are independent and additive risk factors for mortality in colorectal cancer

    PubMed Central

    Kocsis, Judit; Mészáros, Tamás; Madaras, Balázs; Tóth, Éva Katalin; Kamondi, Szilárd; Gál, Péter; Varga, Lilian; Prohászka, Zoltán

    2010-01-01

    Recently, we reported that high soluble Hsp70 (sHsp70) level was a significant predictor of mortality during an almost 3-year-long follow-up period in patients with colorectal cancer. This association was the strongest in the group of <70-year-old female patients as well as in those who were in a less advanced stage of the disease at baseline. According to these observations, measurement of the serum level of sHsp70 is a useful, stage-independent prognostic marker in colorectal cancer, especially in patients without distant metastasis. Since many literature data indicated that measurement of C-reactive protein (CRP) and other acute phase proteins (APPs) may also be suitable for predicting the mortality of patients with colorectal cancer, it seemed reasonable to study whether the effect of sHsp70 and other APPs are related or independent. In order to answer this question, we measured the concentrations of CRP as well as of other complement-related APPs (C1 inhibitor, C3, and C9) along with that of the MASP-2 complement component in the sera of 175 patients with colorectal cancer and known levels of sHsp70, which have been used in our previous study. High (above median) levels of CRP, C1 esterase inhibitor (C1-INH), and sHsp70 were found to be independently associated with poor patient survival, whereas no such association was observed with the other proteins tested. According to the adjusted Cox proportional hazards analysis, the additive effect of high sHsp70, CRP, and C1-INH levels on the survival of patients exceeded that of high sHsp70 alone, with a hazard ratio (HR) of 2.83 (1.13–70.9). In some subgroups of patients, such as in females [HR 4.80 (1.07–21.60)] or in ≤70-year-old patients [HR 11.53 (2.78–47.70)], even greater differences were obtained. These findings indicate that the clinical mortality–prediction value of combined measurements of sHsp70, CRP, and C1-INH with inexpensive methods can be very high, especially in specific subgroups of

  8. Multiple Independent Retroelement Insertions in the Promoter of a Stress Response Gene Have Variable Molecular and Functional Effects in Drosophila

    PubMed Central

    Merenciano, Miriam; Ullastres, Anna; González, Josefa

    2016-01-01

    Promoters are structurally and functionally diverse gene regulatory regions. The presence or absence of sequence motifs and the spacing between the motifs defines the properties of promoters. Recent alternative promoter usage analyses in Drosophila melanogaster revealed that transposable elements significantly contribute to promote diversity. In this work, we analyzed in detail one of the transposable element insertions, named FBti0019985, that has been co-opted to drive expression of CG18446, a candidate stress response gene. We analyzed strains from different natural populations and we found that besides FBti0019985, there are another eight independent transposable elements inserted in the proximal promoter region of CG18446. All nine insertions are solo-LTRs that belong to the roo family. We analyzed the sequence of the nine roo insertions and we investigated whether the different insertions were functionally equivalent by performing 5’-RACE, gene expression, and cold-stress survival experiments. We found that different insertions have different molecular and functional consequences. The exact position where the transposable elements are inserted matters, as they all showed highly conserved sequences but only two of the analyzed insertions provided alternative transcription start sites, and only the FBti0019985 insertion consistently affects CG18446 expression. The phenotypic consequences of the different insertions also vary: only FBti0019985 was associated with cold-stress tolerance. Interestingly, the only previous report of transposable elements inserting repeatedly and independently in a promoter region in D. melanogaster, were also located upstream of a stress response gene. Our results suggest that functional validation of individual structural variants is needed to resolve the complexity of insertion clusters. PMID:27517860

  9. Dependence of P-wave dispersion on mean arterial pressure as an independent hemodynamic variable in school children

    PubMed Central

    González, Emilio F.; Llanes, María del Carmen; Llanes, Merlin Garí; García, Yosvany

    2013-01-01

    Introduction: The relationship between diastolic dysfunction and P-wave dispersion (PWD) in the electrocardiogram has been studied for some time. In this regard, echocardiography is emerging as a diagnostic tool to improve risk stratification for mild hypertension. Objective: To determine the dependence of PWD on the electrocardiogram and on echocardiographic variables in a pediatric population. Methods: 515 children from three elementary schools were studied from a total of 565 children. Those whose parents did not want them to take part in the study, as well as those with known congenital diseases, were excluded. Tests including 12-lead surface ECGs and 4 blood pressure (BP) measurements were performed. Maximum and minimum P-values were measured, and the PWD on the electrocardiogram was calculated. Echocardiography for structural measurements and the pulsed Doppler of mitral flow were also performed. Results: A significant correlation in statistical variables was found between PWD and mean BP for pre-hypertensive and hypertensive children, i.e., r = 0.32, p <0.01 and r = 0.33, p <0.01, respectively. There was a significant correlation found between PWD and the left atrial area (r = 0.45 and p <0.01). Conclusions: We highlight the dependency between PWD, the electrocardiogram and mean blood pressure. We also draw attention to the dependence of PWD on the duration of the mitral inflow A-wave. This result provides an explanation for earlier changes in atrial electrophysiological and hemodynamic characteristics in pediatric patients. PMID:24892616

  10. Independent contributions of the central executive, intelligence, and in-class attentive behavior to developmental change in the strategies used to solve addition problems.

    PubMed

    Geary, David C; Hoard, Mary K; Nugent, Lara

    2012-09-01

    Children's (N=275) use of retrieval, decomposition (e.g., 7=4+3 and thus 6+7=6+4+3), and counting to solve additional problems was longitudinally assessed from first grade to fourth grade, and intelligence, working memory, and in-class attentive behavior was assessed in one or several grades. The goal was to assess the relation between capacity of the central executive component of working memory, controlling for intelligence and in-class attentive behavior, and grade-related changes in children's use of these strategies. The predictor on intercept effects from multilevel models revealed that children with higher central executive capacity correctly retrieved more facts and used the most sophisticated counting procedure more frequently and accurately than their lower capacity peers at the beginning of first grade, but the predictor on slope effects indicated that this advantage disappeared (retrieval) or declined in importance (counting) from first grade to fourth grade. The predictor on slope effects also revealed that from first grade to fourth grade, children with higher capacity adopted the decomposition strategy more quickly than other children. The results remained robust with controls for children's sex, race, school site, speed of encoding Arabic numerals and articulating number words, and mathematics achievement in kindergarten. The results also revealed that intelligence and in-class attentive behavior independently contributed to children's strategy development.

  11. Variable Metastatic Potentials Correlate with Differential Plectin and Vimentin Expression in Syngeneic Androgen Independent Prostate Cancer Cells

    PubMed Central

    Burch, Tanya C.; Watson, Megan T.; Nyalwidhe, Julius O.

    2013-01-01

    Prostate cancer is a clinically heterogeneous disease, ranging from indolent asymptomatic disease to very aggressive metastatic and life threatening forms of the disease. Distant metastasis represents the major lethal cause of prostate cancer. The most critical clinical challenge in the management of the patients is identifying those individuals at risk of developing metastatic disease. To understand the molecular mechanisms of prostate cancer metastasis and identify markers with metastatic potential, we have analyzed protein expression in two syngeneic prostate cancer cells lines PC3-N2 and PC3-ML2 using isobaric tags for relative and absolute quantitation labeling and multi-dimensional protein identification technology liquid chromatography matrix assisted laser desorption ionization tandem mass spectrometry. PC3-N2 is lowly metastatic while PC3-ML2 highly metastatic. A total of 1,756 proteins were identified in the analyses with 130 proteins showing different expression levels (p<0.01) in the two cell lines. Out of these, 68 proteins were found to be significantly up-regulated while 62 are significantly down-regulated in PC3-ML2 cells compared with PC3-N2 cells. The upregulation of plectin and vimentin which were the most significantly differentially expressed were validated by Western blot and their functional relevance with respect to invasion and migration was determined by siRNA gene silencing. To our knowledge, this study is the first to demonstrate that up-regulation of vimentin and plectin expression positively correlates with the invasion and metastasis of androgen-independent PCA. PMID:23717685

  12. Clinical value of morphometric and DNA flow cytometric variables as independent predictors of survival in epithelial ovarian carcinoma: a 5-year follow-up study.

    PubMed

    Veerman, Margot M; van der Wurff, Anneke A M; van de Water, Marije; Kruitwagen, Roy F P M; Feijen, Harrie W H; Vos, Maria Caroline

    2009-09-01

    The aim of this follow-up study is to validate the clinical significance of quantitative morphometric and DNA flow cytometric variables as independent prognostic factors of overall survival and progression-free survival in epithelial ovarian carcinoma. Tumor samples were collected from 135 patients with epithelial ovarian carcinoma at 3 hospitals in the Netherlands. Evaluated clinico-pathologic variables were age, histologic subtype, differentiation grade, clinical stage [International Federation of Gynecology and Obstetrics (FIGO)], presence of ascites, serum CA-125, and the completeness of debulking surgery. Morphometry and DNA flow cytometric techniques were assessed on each tumor sample to determine the mitotic activity index (MAI), volume percentage epithelium, mean nuclear area (MNA), standard deviation of MNA (SD MNA), nuclear perimeter (NP), and DNA ploidy. Univariate analysis showed that differentiation grade, FIGO stage, presence of ascites, preoperative CA-125 levels, DNA ploidy, and MAI, NP, and MNA were of significant prognostic value. After multivariate analysis (using forward Cox proportional hazard analysis), only differentiation grade and FIGO stage remained significant. From this study, we can conclude that morphometry and DNA flow cytometry are not independent prognosticators and therefore have no clinical value in predicting prognosis in ovarian carcinoma.

  13. Plant Functional Diversity Can Be Independent of Species Diversity: Observations Based on the Impact of 4-Yrs of Nitrogen and Phosphorus Additions in an Alpine Meadow

    PubMed Central

    Li, Wei; Cheng, Ji-Min; Yu, Kai-Liang; Epstein, Howard E.; Guo, Liang; Jing, Guang-Hua; Zhao, Jie; Du, Guo-Zhen

    2015-01-01

    Past studies have widely documented the decrease in species diversity in response to addition of nutrients, however functional diversity is often independent from species diversity. In this study, we conducted a field experiment to examine the effect of nitrogen and phosphorus fertilization ((NH4)2 HPO4) at 0, 15, 30 and 60 g m-2 yr-1 (F0, F15, F30 and F60) after 4 years of continuous fertilization on functional diversity and species diversity, and its relationship with productivity in an alpine meadow community on the Tibetan Plateau. To this purpose, three community-weighted mean trait values (specific leaf area, SLA; mature plant height, MPH; and seed size, SS) for 30 common species in each fertilization level were determined; three components of functional diversity (functional richness, FRic; functional evenness, FEve; and Rao’s index of quadratic entropy, FRao) were quantified. Our results showed that: (i) species diversity sharply decreased, but functional diversity remained stable with fertilization; (ii) community-weighted mean traits (SLA and MPH) had a significant increase along the fertilization level; (iii) aboveground biomass was not correlated with functional diversity, but it was significantly correlated with species diversity and MPH. Our results suggest that decreases in species diversity due to fertilization do not result in corresponding changes in functional diversity. Functional identity of species may be more important than functional diversity in influencing aboveground productivity in this alpine meadow community, and our results also support the mass ratio hypothesis; that is, the traits of the dominant species influenced the community biomass production. PMID:26295345

  14. Plant Functional Diversity Can Be Independent of Species Diversity: Observations Based on the Impact of 4-Yrs of Nitrogen and Phosphorus Additions in an Alpine Meadow.

    PubMed

    Li, Wei; Cheng, Ji-Min; Yu, Kai-Liang; Epstein, Howard E; Guo, Liang; Jing, Guang-Hua; Zhao, Jie; Du, Guo-Zhen

    2015-01-01

    Past studies have widely documented the decrease in species diversity in response to addition of nutrients, however functional diversity is often independent from species diversity. In this study, we conducted a field experiment to examine the effect of nitrogen and phosphorus fertilization ((NH4)2 HPO4) at 0, 15, 30 and 60 g m-2 yr-1 (F0, F15, F30 and F60) after 4 years of continuous fertilization on functional diversity and species diversity, and its relationship with productivity in an alpine meadow community on the Tibetan Plateau. To this purpose, three community-weighted mean trait values (specific leaf area, SLA; mature plant height, MPH; and seed size, SS) for 30 common species in each fertilization level were determined; three components of functional diversity (functional richness, FRic; functional evenness, FEve; and Rao's index of quadratic entropy, FRao) were quantified. Our results showed that: (i) species diversity sharply decreased, but functional diversity remained stable with fertilization; (ii) community-weighted mean traits (SLA and MPH) had a significant increase along the fertilization level; (iii) aboveground biomass was not correlated with functional diversity, but it was significantly correlated with species diversity and MPH. Our results suggest that decreases in species diversity due to fertilization do not result in corresponding changes in functional diversity. Functional identity of species may be more important than functional diversity in influencing aboveground productivity in this alpine meadow community, and our results also support the mass ratio hypothesis; that is, the traits of the dominant species influenced the community biomass production. PMID:26295345

  15. Prediction of joint algal toxicity of nano-CeO2/nano-TiO2 and florfenicol: Independent action surpasses concentration addition.

    PubMed

    Wang, Zhuang; Wang, Se; Peijnenburg, Willie J G M

    2016-08-01

    Co-exposure of aquatic organisms to engineered nanoparticles (ENPs) and antibiotics is likely to take place in the environment. However, the impacts of co-exposure on aquatic organisms are virtually unknown and understanding the joint toxicity of ENPs and antibiotics is a topic of importance. The independent action (IA) model and the concentration addition (CA) model are two of the most common approaches to mixture toxicity assessment. In this study, the joint toxicity of two ENPs (nCeO2 and nTiO2) and one antibiotic (florfenicol, FLO) to Chlorella pyrenoidosa was determined to compare the applicability of the IA and the CA model. Concentration-response analyses were performed for single toxicants and for binary mixtures containing FLO and one of the ENPs at two suspended particle concentrations. The effect concentrations and the observed effects of the binary mixtures were compared to the predictions of the joint toxicity. The observed toxicity associated with the nCeO2 or nTiO2 exposure was enhanced by the concomitant FLO exposure. The joint toxicity of nCeO2 and FLO was significantly higher than that of nTiO2 and FLO. Predictions based on the IA and CA models tend to underestimate the overall toxicity (in terms of median effect concentration) of the binary mixtures, but IA performs better than CA, irrespective of the effect level under consideration and the types of mixtures studied. This result underpins the need to consider the effects of mixtures of ENPs and organic chemicals on aquatic organisms, and the practicability of the IA and CA methods in toxicity assessment of ENPs.

  16. Plant Functional Diversity Can Be Independent of Species Diversity: Observations Based on the Impact of 4-Yrs of Nitrogen and Phosphorus Additions in an Alpine Meadow.

    PubMed

    Li, Wei; Cheng, Ji-Min; Yu, Kai-Liang; Epstein, Howard E; Guo, Liang; Jing, Guang-Hua; Zhao, Jie; Du, Guo-Zhen

    2015-01-01

    Past studies have widely documented the decrease in species diversity in response to addition of nutrients, however functional diversity is often independent from species diversity. In this study, we conducted a field experiment to examine the effect of nitrogen and phosphorus fertilization ((NH4)2 HPO4) at 0, 15, 30 and 60 g m-2 yr-1 (F0, F15, F30 and F60) after 4 years of continuous fertilization on functional diversity and species diversity, and its relationship with productivity in an alpine meadow community on the Tibetan Plateau. To this purpose, three community-weighted mean trait values (specific leaf area, SLA; mature plant height, MPH; and seed size, SS) for 30 common species in each fertilization level were determined; three components of functional diversity (functional richness, FRic; functional evenness, FEve; and Rao's index of quadratic entropy, FRao) were quantified. Our results showed that: (i) species diversity sharply decreased, but functional diversity remained stable with fertilization; (ii) community-weighted mean traits (SLA and MPH) had a significant increase along the fertilization level; (iii) aboveground biomass was not correlated with functional diversity, but it was significantly correlated with species diversity and MPH. Our results suggest that decreases in species diversity due to fertilization do not result in corresponding changes in functional diversity. Functional identity of species may be more important than functional diversity in influencing aboveground productivity in this alpine meadow community, and our results also support the mass ratio hypothesis; that is, the traits of the dominant species influenced the community biomass production.

  17. Inter-participant variability in daily physical activity and sedentary time among male youth sport footballers: independent associations with indicators of adiposity and cardiorespiratory fitness.

    PubMed

    Fenton, Sally A M; Duda, Joan L; Barrett, Timothy

    2016-01-01

    Participation in youth sport is assumed to promote and contribute towards more physically active lifestyles among children and adolescents. The aim of this study was to examine inter-participant variability in objectively measured habitual physical activity (PA) behaviours and sedentary time among youth sport participants and their implications for health. One-hundred-and-eighteen male youth sport footballers (Mean ± s = 11.72 ± 1.60) wore a GT3X accelerometer for 7 days. Average daily PA [min · day(-1), in light (LPA), moderate (MPA), vigorous (VPA) and combined moderate-to-vigorous (MVPA)] and sedentary time were calculated. Participants' body mass index adjusted for age and sex (BMI-standard deviation score), per cent body fat (BF%), waist circumference and cardiorespiratory fitness were assessed. Results revealed that variability in daily PA behaviours and sedentary time (min · day(-1)) was associated with BMI-standard deviation score [VPA (-), MVPA (-)], BF% [sedentary time (+), VPA (-), MVPA (-)], waist circumference [sedentary time (+), LPA (-)] and cardiorespiratory fitness [sedentary time (-), MPA (+), VPA (+), MVPA (+)]. Whilst sedentary time and MVPA were not related to health outcomes independent of one another, associations with markers of adiposity and cardiorespiratory fitness were stronger for sedentary time. Sedentary time was also significantly positively related to waist circumference independent of VPA. Results demonstrate inter-participant variability in habitual PA and sedentary time among youth sport participants which holds implications for their health. Thus, promoting PA and, in particular, reducing sedentary time may contribute towards the prevention of adverse health consequences associated with a physically inactive lifestyle for children and adolescents active in the youth sport context.

  18. A mouse variable gene fragment binds to DNA independently of the BCR context: a possible role for immature B-cell repertoire establishment.

    PubMed

    Maranhão, Andrea Queiroz; Costa, Maria Beatriz Walter; Guedes, Leonardo; Moraes-Vieira, Pedro Manoel; Raiol, Tainá; Brigido, Marcelo Macedo

    2013-01-01

    B-cell maturation occurs in several steps and requires constant stimulus for its continuing development. From the emergence of the pre-B-cell receptor, signal transduction stimulates and supports B-cell development. Current viewpoints indicate that both positive selection pressure for autoantigens and tonic signaling constitutively stimulate B-cell maturation. In this work, we tested for the presence of a putative DNA binding site in a variable gene segment in a germline configuration, independently of VDJ recombination. After a survey of the public antibody databases, we chose a single mouse heavy variable gene segment that is highly represented in anti-nucleic acid antibodies and tested it for ssDNA binding. A phage display approach was used to search for intrinsic binding to oligo deoxythymidine. The results revealed that binding to an antigen can be influenced by the use of a specific DNA binding V[Formula: see text] gene segment. Our data support the idea that some variable genes have intrinsic reactivity towards specific types of endogenous autoantigens, and this property may contribute to the establishment of the immature B-cell repertoire.

  19. A Mouse Variable Gene Fragment Binds to DNA Independently of the BCR Context: A Possible Role for Immature B-Cell Repertoire Establishment

    PubMed Central

    Maranhão, Andrea Queiroz; Costa, Maria Beatriz Walter; Guedes, Leonardo; Moraes-Vieira, Pedro Manoel; Raiol, Tainá; Brigido, Marcelo Macedo

    2013-01-01

    B-cell maturation occurs in several steps and requires constant stimulus for its continuing development. From the emergence of the pre-B-cell receptor, signal transduction stimulates and supports B-cell development. Current viewpoints indicate that both positive selection pressure for autoantigens and tonic signaling constitutively stimulate B-cell maturation. In this work, we tested for the presence of a putative DNA binding site in a variable gene segment in a germline configuration, independently of VDJ recombination. After a survey of the public antibody databases, we chose a single mouse heavy variable gene segment that is highly represented in anti-nucleic acid antibodies and tested it for ssDNA binding. A phage display approach was used to search for intrinsic binding to oligo deoxythymidine. The results revealed that binding to an antigen can be influenced by the use of a specific DNA binding V gene segment. Our data support the idea that some variable genes have intrinsic reactivity towards specific types of endogenous autoantigens, and this property may contribute to the establishment of the immature B-cell repertoire. PMID:24023756

  20. Normal mode analysis based on an elastic network model for biomolecules in the Protein Data Bank, which uses dihedral angles as independent variables.

    PubMed

    Wako, Hiroshi; Endo, Shigeru

    2013-06-01

    We have developed a computer program, named PDBETA, that performs normal mode analysis (NMA) based on an elastic network model that uses dihedral angles as independent variables. Taking advantage of the relatively small number of degrees of freedom required to describe a molecular structure in dihedral angle space and a simple potential-energy function independent of atom types, we aimed to develop a program applicable to a full-atom system of any molecule in the Protein Data Bank (PDB). The algorithm for NMA used in PDBETA is the same as the computer program FEDER/2, developed previously. Therefore, the main challenge in developing PDBETA was to find a method that can automatically convert PDB data into molecular structure information in dihedral angle space. Here, we illustrate the performance of PDBETA with a protein-DNA complex, a protein-tRNA complex, and some non-protein small molecules, and show that the atomic fluctuations calculated by PDBETA reproduce the temperature factor data of these molecules in the PDB. A comparison was also made with elastic-network-model based NMA in a Cartesian-coordinate system.

  1. Independent variables in foam clusters

    NASA Astrophysics Data System (ADS)

    Fortes, M. A.; Teixeira, P. I. C.

    2001-11-01

    We find, by counting the degrees of freedom of two-dimensional bubble clusters (finite or periodic) of given topology and bubble areas, that the Plateau laws determine a unique configuration of a finite free cluster, but allow an infinite number of configurations of a periodic cluster. Each of these configurations is associated with a particular strain (stress) state of the cluster; there is in general one unstrained configuration, which corresponds to the minimum of the (surface) energy. Configurations of given topology that satisfy Plateau's laws may only exist in certain ranges of bubble area ratios and/or strains.

  2. Determination of organic additives in mortars by near-IR spectroscopy. A novel approach to designing a sample set with high-variability components.

    PubMed

    Blanco, Marcelo; Peguero, Anna

    2007-02-01

    Industrial mortars consist primarily of a mixture of cement and an aggregate plus a small amount of additives that are used to modify specific properties. Using too high or too low additive rates usually results in the loss of desirable properties in the end product. This entails carefully controlling the amounts of additives added to mortar in order to ensure correct dosing and/or adequate homogeneity in the final mixture. Near-IR (NIR) spectroscopy has proved effective for this purpose as it requires no sample pretreatment and affords expeditious analyses. The purpose of this work was to determine two organic additives (viz. Ad1 and Ad2) in mortars by using partial least squares regression multivariate calibration models constructed from NIR spectroscopic data. The additives are used to expedite setting and increase cohesion between particles in the mortar. In order to ensure that the sample set contained natural variability in the samples, we used a methodology based on experimental design to construct a representative set of samples. This novel design is based on a hexagonal antiprism that encompasses the concentration ranges spanned by the analytes and the variability inherent in each additive. The D-optimality criterion was used to obtain various combinations between Ad1 and Ad2 additive classes. The partial least squares calibration models thus constructed for each additive provided accurate predictions: the intercept and the slope of the plots of predicted values versus reference values for each additive were close to 0 and 1, respectively, and their confidence ranges included the respective value. The ensuing analytical methods were validated by using an external sample set.

  3. Reduced Number of Transitional and Naive B Cells in Addition to Decreased BAFF Levels in Response to the T Cell Independent Immunogen Pneumovax®23.

    PubMed

    Roth, Alena; Glaesener, Stephanie; Schütz, Katharina; Meyer-Bahlburg, Almut

    2016-01-01

    Protective immunity against T cell independent (TI) antigens such as Streptococcus pneumoniae is characterized by antibody production of B cells induced by the combined activation of T cell independent type 1 and type 2 antigens in the absence of direct T cell help. In mice, the main players in TI immune responses have been well defined as marginal zone (MZ) B cells and B-1 cells. However, the existence of human equivalents to these B cell subsets and the nature of the human B cell compartment involved in the immune reaction remain elusive. We therefore analyzed the effect of a TI antigen on the B cell compartment through immunization of healthy individuals with the pneumococcal polysaccharide (PnPS)-based vaccine Pneumovax®23, and subsequent characterization of B cell subpopulations. Our data demonstrates a transient decrease of transitional and naïve B cells, with a concomitant increase of IgA+ but not IgM+ or IgG+ memory B cells and a predominant generation of PnPS-specific IgA+ producing plasma cells. No alterations could be detected in T cells, or proposed human B-1 and MZ B cell equivalents. Consistent with the idea of a TI immune response, antigen-specific memory responses could not be observed. Finally, BAFF, which is supposed to drive class switching to IgA, was unexpectedly found to be decreased in serum in response to Pneumovax®23. Our results demonstrate that a characteristic TI response induced by Pneumovax®23 is associated with distinct phenotypical and functional changes within the B cell compartment. Those modulations occur in the absence of any modulations of T cells and without the development of a specific memory response.

  4. Reduced Number of Transitional and Naive B Cells in Addition to Decreased BAFF Levels in Response to the T Cell Independent Immunogen Pneumovax®23

    PubMed Central

    Roth, Alena; Glaesener, Stephanie; Schütz, Katharina; Meyer-Bahlburg, Almut

    2016-01-01

    Protective immunity against T cell independent (TI) antigens such as Streptococcus pneumoniae is characterized by antibody production of B cells induced by the combined activation of T cell independent type 1 and type 2 antigens in the absence of direct T cell help. In mice, the main players in TI immune responses have been well defined as marginal zone (MZ) B cells and B-1 cells. However, the existence of human equivalents to these B cell subsets and the nature of the human B cell compartment involved in the immune reaction remain elusive. We therefore analyzed the effect of a TI antigen on the B cell compartment through immunization of healthy individuals with the pneumococcal polysaccharide (PnPS)-based vaccine Pneumovax®23, and subsequent characterization of B cell subpopulations. Our data demonstrates a transient decrease of transitional and naïve B cells, with a concomitant increase of IgA+ but not IgM+ or IgG+ memory B cells and a predominant generation of PnPS-specific IgA+ producing plasma cells. No alterations could be detected in T cells, or proposed human B-1 and MZ B cell equivalents. Consistent with the idea of a TI immune response, antigen-specific memory responses could not be observed. Finally, BAFF, which is supposed to drive class switching to IgA, was unexpectedly found to be decreased in serum in response to Pneumovax®23. Our results demonstrate that a characteristic TI response induced by Pneumovax®23 is associated with distinct phenotypical and functional changes within the B cell compartment. Those modulations occur in the absence of any modulations of T cells and without the development of a specific memory response. PMID:27031098

  5. Independent Contributions of the Central Executive, Intelligence, and In-Class Attentive Behavior to Developmental Change in the Strategies Used to Solve Addition Problems

    ERIC Educational Resources Information Center

    Geary, David C.; Hoard, Mary K.; Nugent, Lara

    2012-01-01

    Children's (N = 275) use of retrieval, decomposition (e.g., 7 = 4+3 and thus 6+7 = 6+4+3), and counting to solve additional problems was longitudinally assessed from first grade to fourth grade, and intelligence, working memory, and in-class attentive behavior was assessed in one or several grades. The goal was to assess the relation between…

  6. HbA1c Variability as an Independent Risk Factor for Diabetic Retinopathy in Type 1 Diabetes: A German/Austrian Multicenter Analysis on 35,891 Patients

    PubMed Central

    Hermann, Julia M.; Hammes, Hans-Peter; Rami-Merhar, Birgit; Rosenbauer, Joachim; Schütt, Morten; Siegel, Erhard; Holl, Reinhard W.

    2014-01-01

    Objective This study aimed to analyze the effect of HbA1c variability on the occurrence of diabetic retinopathy in type 1 diabetes patients. Patients and Methods 35,891 patients with childhood, adolescent or adult onset of type 1 diabetes from a large multicentre survey, the German/Austrian prospective documentation system (DPV), were analysed. Cox proportional hazard models were used to examine whether intra-individual HbA1c variability expressed as variation coefficient is an independent risk factor for the occurrence of diabetic retinopathy. Results Kaplan-Meier curves stratified by median HbA1c and variation coefficient revealed that retinopathy-free survival probability is lower when both median HbA1c and HbA1c variability are above the 50th percentile. Cox regression models confirmed this finding: After adjustment for age at diabetes onset, gender and median HbA1c, HbA1c variability was independently associated with the occurrence of diabetic retinopathy. Time-covariate interactions used to model non-proportionality indicated an effect decreasing with duration of diabetes for both median HbA1c and HbA1c variability. Predictive accuracy increased significantly when adding HbA1c variability to the Cox regression model. Conclusions In patients with type 1 diabetes, HbA1c variability adds to the risk of diabetic retinopathy independently of average metabolic control. PMID:24609115

  7. Evidence for protein kinase C-dependent and -independent activation of mitogen-activated protein kinase in T cells: potential role of additional diacylglycerol binding proteins.

    PubMed

    Puente, L G; Stone, J C; Ostergaard, H L

    2000-12-15

    Activation of mitogen-activated protein kinases (MAPK) is a critical signal transduction event for CTL activation, but the signaling mechanisms responsible are not fully characterized. Protein kinase C (PKC) is thought to contribute to MAPK activation following TCR stimulation. We have found that dependence on PKC varies with the method used to stimulate the T cells. Extracellular signal-regulated kinase (ERK) activation in CTL stimulated with soluble cross-linked anti-CD3 is completely inhibited by the PKC inhibitor bisindolylmaleimide (BIM). In contrast, only the later time points in the course of ERK activation are sensitive to BIM when CTL are stimulated with immobilized anti-CD3, a condition that stimulates CTL degranulation. Surprisingly, MAPK activation in response to immobilized anti-CD3 is strongly inhibited at all time points by the diacylglycerol (DAG)-binding domain inhibitor calphostin C implicating the contribution of a DAG-dependent but PKC-independent pathway in the activation of ERK in CTL clones. Chronic exposure to phorbol ester down-regulates the expression of DAG-responsive PKC isoforms; however, this treatment of CTL clones does not inhibit anti-CD3-induced activation of MAPK. Phorbol ester-treated cells have reduced expression of several isoforms of PKC but still express the recently described DAG-binding Ras guanylnucleotide-releasing protein. These results indicate that the late phase of MAPK activation in CTL clones in response to immobilized anti-CD3 stimulation requires PKC while the early phase requires a DAG-dependent, BIM-resistant component.

  8. Variability in Ozone in the Tropical Upper Troposphere-Lower Stratosphere from the 1998-2000 SHADOZ (Southern Hemisphere Additional Ozonesondes) Data

    NASA Technical Reports Server (NTRS)

    Thompson, A. M.; Witte, J. C.; McPeters, R. D.; Schmidlin, F. J.; Oltmans, S. J.; Kirchhoff, V. W. J. H.; Coetzee, G. J. R.; Posny, F.; Kawakami, S.; Ogawa, T.; Bhartia, P. K. (Technical Monitor)

    2002-01-01

    The first view of lower stratospheric and upper tropospheric structure from sondes is provided by a 3-year, 10-site record from the Southern Hemisphere ADditional OZonesondes (SHADOZ) network: . Observations covering 1998-2000 were made over Ascension Island; Nairobi, Kenya; Irene, South Africa; Reunion Island; Watukosek, Java; Fiji; Tahiti; American Samoa; San Cristobal, Galapagos; Natal, Brazil. Taking the UT/LS (upper troposphere- lower stratosphere) as the region between 12 and 17 km, we examine ozone variability in this region on a week-to-week and seasonal basis. The tropopause is lower in September-October-November than in March-April-May, when ozone is a minimum at most SHADOZ stations. A zonal wave-one pattern (referring to ozone mixing ratios greater over the Atlantic and adjacent continents than over the Pacific and eastern Indian Ocean), persists all year. The wave, predominantly in the troposphere and with variable magnitude, appears to be due to general circulation - with subsidence over the Atlantic and frequent deep convection over the Pacific and Indian Ocean. The variability of deep convection most prominent at Java, Fiji, Samoa and Natal - is explored in time-vs-altitude ozone curtains. Stratospheric incursions into the troposphere are most prominent in soundings at Irene and Reunion Island.

  9. Variability in Ozone in the Tropical Upper Troposphere-Lower Stratosphere from the 1998 - 200 SHADOZ (Southern Hemisphere ADditional Ozonesondes) Data

    NASA Astrophysics Data System (ADS)

    Thompson, A.; Witte, J.; Oltmans, S.; Coetzee, G.; Kawakami, S.; Ogawa, T.

    The first view of lower stratospheric and upper tropospheric structure from sondes is provided by a 3 year, 10-site record from the Southern Hemisphere ADditional- OZonesondes (SHADOZ) network: . Observations covering 1998-2000 were made over Ascension Island; Nairobi, Kenya; Irene, South Africa; Reunion Island; Watukosek, Java; Fiji; Tahiti; American Samoa; San Crist"bal, Galapagos; Natal, Brazil. Taking the UT/LS (upper troposphere-lower stratosphere) as the region between 12 and 17 km, we examine ozone variability in this region on a week- to- week and seasonal basis. The tropopause is lower in September-October-November than in March-April- May, when ozone is a minimum at most SHADOZ stations. A zonal wave-one pattern (referring to ozone mixing ratios greater over the Atlantic and adjacent continents than over the Pacific and eastern Indian Ocean), persists all year. The wave, predominantly in the troposphere and with variable magnitude, appears to be due to general circulation - with subsidence over the Atlantic and frequent deep convection over the Pacific and Indian Ocean. The variability of deep convection - most prominent at Java, Fiji, Samoa and Natal - is explored in time-vs-altitude ozone curtains. Stratospheric incursions into the troposphere are most prominent in soundings at Irene and Reunion Island.

  10. Evidence indicating independent assortment of framework and complementarity-determining segments of the variable regions of rabbit light chains. Delineation of a possible J minigene.

    PubMed

    Kabat, E A; Wu, T T; Bilofsky, H

    1980-07-01

    Amino acid sequences of rabbit light chains show considerable evidence of independent assortment of framework (FR) and complementarity-determining (CDR) segments. This suggests that they are coded for by independent genetic units (minigaenes) and that individual light chains are assembled somatically by recombining these units. Identical FR sets with multiple members generally comprise chains with different specificities, whereas identical CDR sets tend to have chains of a single specificity. A J segment, which, by analogy with mouse light chains, is made up of the last two residues of CDR3 plus all of FR4, contained 18 different sets and could contribute to diversity generated by CDR3. The longest segment, FR3, had a very large number of sets. Evidence is presented showing that the number of sets could be substantially reduced by permitting FR3 to be formed by two independently assorting segments comprising residues 57-68 and 69-88.

  11. An Investigation of the Relationship of Intellective and Personality Variables to Success in an Independent Study Science Course Through the Use of a Modified Multiple Regression Model.

    ERIC Educational Resources Information Center

    Szabo, Michael; Feldhusen, John F.

    This is an empirical study of selected learner characteristics and their relation to academic success, as indicated by course grades, in a structured independent study learning program. This program, called the Audio-Tutorial System, was utilized in an undergraduate college course in the biological sciences. By use of multiple regression analysis,…

  12. An efficient method for variable region assembly in the construction of scFv phage display libraries using independent strand amplification.

    PubMed

    Sotelo, Pablo; Collazo, Noberto; Zuñiga, Roberto; Gutiérrez-González, Matías; Catalán, Diego; Ribeiro, Carolina Hager; Aguillón, Juan Carlos; Molina, María Carmen

    2012-01-01

    Phage display library technology is a common method to produce human antibodies. In this technique, the immunoglobulin variable regions are displayed in a bacteriophage in a way that each filamentous virus displays the product of a single antibody gene on its surface. From the collection of different phages, it is possible to isolate the virus that recognizes specific targets. The most common form in which to display antibody variable regions in the phage is the single chain variable fragment format (scFv), which requires assembly of the heavy and light immunoglobulin variable regions in a single gene. In this work, we describe a simple and efficient method for the assembly of immunoglobulin heavy and light chain variable regions in a scFv format. This procedure involves a two-step reaction: (1) DNA amplification to produce the single strand form of the heavy or light chain gene required for the fusion; and (2) mixture of both single strand products followed by an assembly reaction to construct a complete scFv gene. Using this method, we produced 6-fold more scFv encoding DNA than the commonly used splicing by overlap extension PCR (SOE-PCR) approach. The scFv gene produced by this method also proved to be efficient in generating a diverse scFv phage display library. From this scFv library, we obtained phages that bound several non-related antigens, including recombinant proteins and rotavirus particles.

  13. The 1998-2000 SHADOZ (Southern Hemisphere ADditional OZonesondes) Tropical Ozone Climatology. 2; Stratospheric and Tropospheric Ozone Variability and the Zonal Wave-One

    NASA Technical Reports Server (NTRS)

    Thompson, Anne M.; Witte, Jacquelyn C.; Oltmans, Samuel J.; Schmidlin, Francis J.; Logan, Jennifer A.; Fujiwara, Masatomo; Kirchhoff, Volker W. J. H.; Posny, Francoise; Coetzee, Gert J. R.; Hoegger, Bruno; Bhartia, P. K. (Technical Monitor)

    2002-01-01

    This is the second 'reference' or 'archival' paper for the SHADOZ (Southern Hemisphere Additional Ozonesondes) network and is a follow-on to the recently accepted paper with similar first part of title. The latter paper compared SHADOZ total ozone with satellite and ground-based instruments and showed that the equatorial wave-one in total ozone is in the troposphere. The current paper presents details of the wave-one structure and the first overview of tropospheric ozone variability over the southern Atlantic, Pacific and Indian Ocean basins. The principal new result is that signals of climate effects, convection and offsets between biomass burning seasonality and tropospheric ozone maxima suggest that dynamical factors are perhaps more important than pollution in determining the tropical distribution of tropospheric ozone. The SHADOZ data at () are setting records in website visits and are the first time that the zonal view of tropical ozone structure has been recorded - thanks to the distribution of the 10 sites that make up this validation network.

  14. The influence of environmental variables on the presence of white sharks, Carcharodon carcharias at two popular Cape Town bathing beaches: a generalized additive mixed model.

    PubMed

    Weltz, Kay; Kock, Alison A; Winker, Henning; Attwood, Colin; Sikweyiya, Monwabisi

    2013-01-01

    Shark attacks on humans are high profile events which can significantly influence policies related to the coastal zone. A shark warning system in South Africa, Shark Spotters, recorded 378 white shark (Carcharodon carcharias) sightings at two popular beaches, Fish Hoek and Muizenberg, during 3690 six-hour long spotting shifts, during the months September to May 2006 to 2011. The probabilities of shark sightings were related to environmental variables using Binomial Generalized Additive Mixed Models (GAMMs). Sea surface temperature was significant, with the probability of shark sightings increasing rapidly as SST exceeded 14 °C and approached a maximum at 18 °C, whereafter it remains high. An 8 times (Muizenberg) and 5 times (Fish Hoek) greater likelihood of sighting a shark was predicted at 18 °C than at 14 °C. Lunar phase was also significant with a prediction of 1.5 times (Muizenberg) and 4 times (Fish Hoek) greater likelihood of a shark sighting at new moon than at full moon. At Fish Hoek, the probability of sighting a shark was 1.6 times higher during the afternoon shift compared to the morning shift, but no diel effect was found at Muizenberg. A significant increase in the number of shark sightings was identified over the last three years, highlighting the need for ongoing research into shark attack mitigation. These patterns will be incorporated into shark awareness and bather safety campaigns in Cape Town. PMID:23874668

  15. The influence of environmental variables on the presence of white sharks, Carcharodon carcharias at two popular Cape Town bathing beaches: a generalized additive mixed model.

    PubMed

    Weltz, Kay; Kock, Alison A; Winker, Henning; Attwood, Colin; Sikweyiya, Monwabisi

    2013-01-01

    Shark attacks on humans are high profile events which can significantly influence policies related to the coastal zone. A shark warning system in South Africa, Shark Spotters, recorded 378 white shark (Carcharodon carcharias) sightings at two popular beaches, Fish Hoek and Muizenberg, during 3690 six-hour long spotting shifts, during the months September to May 2006 to 2011. The probabilities of shark sightings were related to environmental variables using Binomial Generalized Additive Mixed Models (GAMMs). Sea surface temperature was significant, with the probability of shark sightings increasing rapidly as SST exceeded 14 °C and approached a maximum at 18 °C, whereafter it remains high. An 8 times (Muizenberg) and 5 times (Fish Hoek) greater likelihood of sighting a shark was predicted at 18 °C than at 14 °C. Lunar phase was also significant with a prediction of 1.5 times (Muizenberg) and 4 times (Fish Hoek) greater likelihood of a shark sighting at new moon than at full moon. At Fish Hoek, the probability of sighting a shark was 1.6 times higher during the afternoon shift compared to the morning shift, but no diel effect was found at Muizenberg. A significant increase in the number of shark sightings was identified over the last three years, highlighting the need for ongoing research into shark attack mitigation. These patterns will be incorporated into shark awareness and bather safety campaigns in Cape Town.

  16. The Influence of Environmental Variables on the Presence of White Sharks, Carcharodon carcharias at Two Popular Cape Town Bathing Beaches: A Generalized Additive Mixed Model

    PubMed Central

    Weltz, Kay; Kock, Alison A.; Winker, Henning; Attwood, Colin; Sikweyiya, Monwabisi

    2013-01-01

    Shark attacks on humans are high profile events which can significantly influence policies related to the coastal zone. A shark warning system in South Africa, Shark Spotters, recorded 378 white shark (Carcharodon carcharias) sightings at two popular beaches, Fish Hoek and Muizenberg, during 3690 six-hour long spotting shifts, during the months September to May 2006 to 2011. The probabilities of shark sightings were related to environmental variables using Binomial Generalized Additive Mixed Models (GAMMs). Sea surface temperature was significant, with the probability of shark sightings increasing rapidly as SST exceeded 14°C and approached a maximum at 18°C, whereafter it remains high. An 8 times (Muizenberg) and 5 times (Fish Hoek) greater likelihood of sighting a shark was predicted at 18°C than at 14°C. Lunar phase was also significant with a prediction of 1.5 times (Muizenberg) and 4 times (Fish Hoek) greater likelihood of a shark sighting at new moon than at full moon. At Fish Hoek, the probability of sighting a shark was 1.6 times higher during the afternoon shift compared to the morning shift, but no diel effect was found at Muizenberg. A significant increase in the number of shark sightings was identified over the last three years, highlighting the need for ongoing research into shark attack mitigation. These patterns will be incorporated into shark awareness and bather safety campaigns in Cape Town. PMID:23874668

  17. Independence Is.

    ERIC Educational Resources Information Center

    Stickney, Sharon

    This workbook is designed to help participants of the Independence Training Program (ITP) to achieve a definition of "independence." The program was developed for teenage girls. The process for developing the concept of independence consists of four steps. Step one instructs the participant to create an imaginary situation where she is completely…

  18. Are Independent Probes Truly Independent?

    ERIC Educational Resources Information Center

    Camp, Gino; Pecher, Diane; Schmidt, Henk G.; Zeelenberg, Rene

    2009-01-01

    The independent cue technique has been developed to test traditional interference theories against inhibition theories of forgetting. In the present study, the authors tested the critical criterion for the independence of independent cues: Studied cues not presented during test (and unrelated to test cues) should not contribute to the retrieval…

  19. Optimization of medium components and cultural variables for enhanced production of acidic high maltose-forming and Ca2+-independent α-amylase by Bacillus acidicola.

    PubMed

    Sharma, Archana; Satyanarayana, Tulasi

    2011-05-01

    The production of acidic α-amylase by a novel acidophilic bacterium Bacillus acidicola TSAS1 was optimized in submerged fermentation using statistical approaches. The process parameters that significantly affected α-amylase production (starch, K(2)HPO(4), inoculum size and temperature) were identified by Plackett and Burman design. The optimum levels of the significant variables as determined using central composite design of response surface methodology are starch (2.75%), K(2)HPO(4) (0.01%), inoculum size [2% (v/v) containing 1.9×10(8) CFU ml(-1)], and temperature (33°C). An overall 2.4 and 2.9-fold increase in enzyme production has been attained in batch and fed-batch fermentations in the laboratory fermentor, respectively.

  20. The prediction of in-hospital mortality by amino terminal pro-brain natriuretic peptide (NT-proBNP) levels and other independent variables in acutely ill patients with suspected heart disease.

    PubMed

    Kellett, John

    2005-06-01

    BACKGROUND: Amino terminal pro-brain natriuretic peptide (NT-proBNP) measurement can detect and assess heart failure. However, compared with traditional clinical parameters, its value in predicting the in-hospital mortality of patients with suspected heart disease has not been reported. METHODS: We examined the ability of 11 continuous and 21 categorical variables, including NT-proBNP levels measured at the time of admission, to predict in-hospital mortality. The setting was a small Irish rural hospital where 342 consecutive patients with suspected heart disease were admitted as acute medical emergencies. RESULTS: The 31 patients who died while in hospital had significantly higher NT-proBNP levels on admission than patients discharged alive (11,548+/-13,531 vs. 3805+/-6914 pg/mL, p<0.0001). Patients who died in-hospital were older, had significantly higher white cell counts, blood urea and modified early warning (MEW) scores, and lower temperatures, blood pressures and oxygen saturation. Four variables were found to be independent predictors of in-hospital mortality: a systolic blood pressure equal to or below 100 mm Hg, a urea level above 13 mmol/L, a white cell count greater than 13*10(9)/L and a NT-proBNP level greater than or equal to 11,500 pg/mL. The presence of three of these variables was associated with an in-hospital mortality rate of 54%. CONCLUSIONS: Four variables (i.e. hypotension, elevated urea, leukocytosis and elevated NT-proBNP levels) are comparable independent predictors of in-hospital mortality.

  1. DNA methylation patterns in luminal breast cancers differ from non-luminal subtypes and can identify relapse risk independent of other clinical variables.

    PubMed

    Kamalakaran, Sitharthan; Varadan, Vinay; Giercksky Russnes, Hege E; Levy, Dan; Kendall, Jude; Janevski, Angel; Riggs, Michael; Banerjee, Nilanjana; Synnestvedt, Marit; Schlichting, Ellen; Kåresen, Rolf; Shama Prasada, K; Rotti, Harish; Rao, Ramachandra; Rao, Laxmi; Eric Tang, Man-Hung; Satyamoorthy, K; Lucito, Robert; Wigler, Michael; Dimitrova, Nevenka; Naume, Bjorn; Borresen-Dale, Anne-Lise; Hicks, James B

    2011-02-01

    The diversity of breast cancers reflects variations in underlying biology and affects the clinical implications for patients. Gene expression studies have identified five major subtypes- Luminal A, Luminal B, basal-like, ErbB2+ and Normal-Like. We set out to determine the role of DNA methylation in subtypes by performing genome-wide scans of CpG methylation in breast cancer samples with known expression-based subtypes. Unsupervised hierarchical clustering using a set of most varying loci clustered the tumors into a Luminal A majority (82%) cluster, Basal-like/ErbB2+ majority (86%) cluster and a non-specific cluster with samples that were also inconclusive in their expression-based subtype correlations. Contributing methylation loci were both gene associated loci (30%) and non-gene associated (70%), suggesting subtype dependant genome-wide alterations in the methylation landscape. The methylation patterns of significant differentially methylated genes in luminal A tumors are similar to those identified in CD24 + luminal epithelial cells and the patterns in basal-like tumors similar to CD44 + breast progenitor cells. CpG islands in the HOXA cluster and other homeobox (IRX2, DLX2, NKX2-2) genes were significantly more methylated in Luminal A tumors. A significant number of genes (2853, p < 0.05) exhibited expression-methylation correlation, implying possible functional effects of methylation on gene expression. Furthermore, analysis of these tumors by using follow-up survival data identified differential methylation of islands proximal to genes involved in Cell Cycle and Proliferation (Ki-67, UBE2C, KIF2C, HDAC4), angiogenesis (VEGF, BTG1, KLF5), cell fate commitment (SPRY1, OLIG2, LHX2 and LHX5) as having prognostic value independent of subtypes and other clinical factors.

  2. Salam's independence

    NASA Astrophysics Data System (ADS)

    Fraser, Gordon

    2009-01-01

    In his kind review of my biography of the Nobel laureate Abdus Salam (December 2008 pp45-46), John W Moffat wrongly claims that Salam had "independently thought of the idea of parity violation in weak interactions".

  3. Maintaining Independence.

    ERIC Educational Resources Information Center

    Upah-Bant, Marilyn

    1978-01-01

    Describes the over-all business and production operation of the "Daily Illini" at the University of Illinois to show how this college publication has assumed the burdens and responsibilities of true independence. (GW)

  4. Effectiveness of the Touch Math Technique in Teaching Basic Addition to Children with Autism

    ERIC Educational Resources Information Center

    Yikmis, Ahmet

    2016-01-01

    This study aims to reveal whether the touch math technique is effective in teaching basic addition to children with autism. The dependent variable of this study is the children's skills to solve addition problems correctly, whereas teaching with the touch math technique is the independent variable. Among the single-subject research models, a…

  5. Sex-specific variability and a 'cage effect' independently mask a neuropathic pain quantitative trait locus detected in a whole genome scan.

    PubMed

    Devor, Marshall; Gilad, Amit; Arbilly, Michal; Nissenbaum, Jonathan; Yakir, Benjamin; Raber, Pnina; Minert, Anne; Pisanté, Anne; Darvasi, Ariel

    2007-08-01

    Sex and environment may dramatically affect genetic studies, and thus should be carefully considered. Beginning with two inbred mouse strains with contrasting phenotype in the neuroma model of neuropathic pain (autotomy), we established a backcross population on which we conducted a genome-wide scan. The backcross population was partially maintained in small social groups and partially in isolation. The genome scan detected one previously reported quantitative trait locus (QTL) on chromosome 15 (pain1), but no additional QTLs were found. Interestingly, group caging introduced phenotypic noise large enough to completely mask the genetic effect of the chromosome 15 QTL. The reason appears to be that group-caging animals from the low-autotomy strain together with animals from the high-autotomy strain dramatically increases autotomy in the otherwise low-autotomy mice (males or females). The converse, suppression of pain behaviour in the high-autotomy strain when caged with the low-autotomy strain was also observed, but only in females. Even in isolated mice, the genetic effect of the chromosome 15 QTL was significant only in females. To determine why, we evaluated autotomy levels of females in 12 different inbred stains of mice and compared them to previously reported levels for males. Strikingly larger environmental variation was observed in males than in females for this pain phenotype. The high baseline variance in males can explain the difficulty in detecting the genetic effect, which was readily seen in females. Our study emphasizes the importance of sex and environment in the genetic analysis of pain.

  6. Independent Living.

    ERIC Educational Resources Information Center

    Nathanson, Jeanne H., Ed.

    1994-01-01

    This issue of "OSERS" addresses the subject of independent living of individuals with disabilities. The issue includes a message from Judith E. Heumann, the Assistant Secretary of the Office of Special Education and Rehabilitative Services (OSERS), and 10 papers. Papers have the following titles and authors: "Changes in the Rehabilitation Act of…

  7. Understanding independence

    NASA Astrophysics Data System (ADS)

    Annan, James; Hargreaves, Julia

    2016-04-01

    In order to perform any Bayesian processing of a model ensemble, we need a prior over the ensemble members. In the case of multimodel ensembles such as CMIP, the historical approach of ``model democracy'' (i.e. equal weight for all models in the sample) is no longer credible (if it ever was) due to model duplication and inbreeding. The question of ``model independence'' is central to the question of prior weights. However, although this question has been repeatedly raised, it has not yet been satisfactorily addressed. Here I will discuss the issue of independence and present a theoretical foundation for understanding and analysing the ensemble in this context. I will also present some simple examples showing how these ideas may be applied and developed.

  8. Independence test for sparse data

    NASA Astrophysics Data System (ADS)

    García, J. E.; González-López, V. A.

    2016-06-01

    In this paper a new non-parametric independence test is presented. García and González-López (2014) [1] introduced the LIS test for the hypothesis of independence between two continuous random variables, the test proposed in this work is a generalization of the LIS test. The new test does not require the assumption of continuity for the random variables, it test is applied to two datasets and also compared with the Pearson's Chi-squared test.

  9. Studying the Independent School Library

    ERIC Educational Resources Information Center

    Cahoy, Ellysa Stern; Williamson, Susan G.

    2008-01-01

    In 2005, the American Association of School Librarians' Independent Schools Section conducted a national survey of independent school libraries. This article analyzes the results of the survey, reporting specialized data and information regarding independent school library budgets, collections, services, facilities, and staffing. Additionally, the…

  10. Variability for Categorical Variables

    ERIC Educational Resources Information Center

    Kader, Gary D.; Perry, Mike

    2007-01-01

    Introductory statistics textbooks rarely discuss the concept of variability for a categorical variable and thus, in this case, do not provide a measure of variability. The impression is thus given that there is no measurement of variability for a categorical variable. A measure of variability depends on the concept of variability. Research has…

  11. Developing independence.

    PubMed

    Turnbull, A P; Turnbull, H R

    1985-03-01

    The transition from living a life as others want (dependence) to living it as the adolescent wants to live it (independence) is extraordinarily difficult for most teen-agers and their families. The difficulty is compounded in the case of adolescents with disabilities. They are often denied access to the same opportunities of life that are accessible to the nondisabled. They face special problems in augmenting their inherent capacities so that they can take fuller advantage of the accommodations that society makes in an effort to grant them access. In particular, they need training designed to increase their capacities to make, communicate, implement, and evaluate their own life-choices. The recommendations made in this paper are grounded in the long-standing tradition of parens patriae and enlightened paternalism; they seek to be deliberately and cautiously careful about the lives of adolescents with disabilities and their families. We based them on the recent tradition of anti-institutionalism and they are also consistent with some of the major policy directions of the past 15-20 years. These include: normalization, integration, and least-restrictive alternatives; the unity and integrity of the family; the importance of opportunities for self-advocacy; the role of consumer consent and choice in consumer-professional relationships; the need for individualized services; the importance of the developmental model as a basis for service delivery; the value of economic productivity of people with disabilities; and the rights of habilitation, amelioration, and prevention. PMID:3156827

  12. Developing independence.

    PubMed

    Turnbull, A P; Turnbull, H R

    1985-03-01

    The transition from living a life as others want (dependence) to living it as the adolescent wants to live it (independence) is extraordinarily difficult for most teen-agers and their families. The difficulty is compounded in the case of adolescents with disabilities. They are often denied access to the same opportunities of life that are accessible to the nondisabled. They face special problems in augmenting their inherent capacities so that they can take fuller advantage of the accommodations that society makes in an effort to grant them access. In particular, they need training designed to increase their capacities to make, communicate, implement, and evaluate their own life-choices. The recommendations made in this paper are grounded in the long-standing tradition of parens patriae and enlightened paternalism; they seek to be deliberately and cautiously careful about the lives of adolescents with disabilities and their families. We based them on the recent tradition of anti-institutionalism and they are also consistent with some of the major policy directions of the past 15-20 years. These include: normalization, integration, and least-restrictive alternatives; the unity and integrity of the family; the importance of opportunities for self-advocacy; the role of consumer consent and choice in consumer-professional relationships; the need for individualized services; the importance of the developmental model as a basis for service delivery; the value of economic productivity of people with disabilities; and the rights of habilitation, amelioration, and prevention.

  13. Ground-water monitoring plan, water quality, and variability of agricultural chemicals in the Missouri River alluvial aquifer near the City of Independence, Missouri, well field, 1998-2000

    USGS Publications Warehouse

    Kelly, Brian P.

    2002-01-01

    A detailed ground-water sampling plan was developed and executed for 64 monitoring wells in the city of Independence well field to characterize ground-water quality in the 10-year zone of contribution. Samples were collected from monitoring wells, combined Independence well field pumpage, and the Missouri River at St. Joseph, Missouri, from 1998 through 2000. In 328 ground-water samples from the 64 monitoring wells and combined well field pumpage samples, specific conductance values ranged from 511 to 1,690 microsiemens per centimeter at 25 degrees Celsius, pH values ranged from 6.4 to 7.7, water temperature ranged from 11.3 to 23.6 degrees Celsius, and dissolved oxygen concentrations ranged from 0 to 3.3 milligrams per liter. In 12 samples from the combined well field pumpage samples, specific conductance values ranged from 558 to 856 microsiemens per centimeter at 25 degrees Celsius, pH values ranged from 6.9 to 7.7, water temperature ranged from 5.8 to 22.9 degrees Celsius, and dissolved oxygen concentrations ranged from 0 to 2.4 milligrams per liter. In 45 Missouri River samples, specific conductance values ranged from 531 to 830 microsiemens per centimeter at 25 degrees Celsius, pH ranged from 7.2 to 8.7, water temperature ranged from 0 to 30 degrees Celsius, and dissolved oxygen concentrations ranged from 5.0 to 17.6 milligrams per liter. The secondary maximum contaminant level for sulfate in drinking water was exceeded once in samples from two monitoring wells, the maximum contaminant level (MCL) for antimony was exceeded once in a sample from one monitoring well, and the MCL for barium was exceeded once in a sample from one monitoring well. The MCL for iron was exceeded in samples from all monitoring wells except two. The MCL for manganese was exceeded in all samples from monitoring wells and combined well field pumpage. Enzyme linked immunoassay methods indicate total benzene, toluene, ethyl benzene, and xylene (BTEX) was detected in samples from five

  14. Food additives

    PubMed Central

    Spencer, Michael

    1974-01-01

    Food additives are discussed from the food technology point of view. The reasons for their use are summarized: (1) to protect food from chemical and microbiological attack; (2) to even out seasonal supplies; (3) to improve their eating quality; (4) to improve their nutritional value. The various types of food additives are considered, e.g. colours, flavours, emulsifiers, bread and flour additives, preservatives, and nutritional additives. The paper concludes with consideration of those circumstances in which the use of additives is (a) justified and (b) unjustified. PMID:4467857

  15. Biographical factors of occupational independence.

    PubMed

    Müller, G F

    2001-10-01

    The present study examined biographical factors of occupational independence including any kind of nonemployed profession. Participants were 59 occupationally independent and 58 employed persons of different age (M = 36.3 yr.), sex, and profession. They were interviewed on variables like family influence, educational background, occupational role models, and critical events for choosing a particular type of occupational career. The obtained results show that occupationally independent people reported stronger family ties, experienced fewer restrictions of formal education, and remembered fewer negative role models than the employed people. Implications of these results are discussed. PMID:11783553

  16. Selective Influence through Conditional Independence.

    ERIC Educational Resources Information Center

    Dzhafarov, Ehtibar N.

    2003-01-01

    Presents a generalization and improvement for the definition proposed by E. Dzhafarov (2001) for selectiveness in the dependence of several random variables on several (sets of) external factors. This generalization links the notion of selective influence with that of conditional independence. (SLD)

  17. The combined inhibitory effect of the adenosine A1 and cannabinoid CB1 receptors on cAMP accumulation in the hippocampus is additive and independent of A1 receptor desensitization.

    PubMed

    Serpa, André; Correia, Sara; Ribeiro, Joaquim A; Sebastião, Ana M; Cascalheira, José F

    2015-01-01

    Adenosine A1 and cannabinoid CB1 receptors are highly expressed in hippocampus where they trigger similar transduction pathways. We investigated how the combined acute activation of A1 and CB1 receptors modulates cAMP accumulation in rat hippocampal slices. The CB1 agonist WIN55212-2 (0.3-30 μM) decreased forskolin-stimulated cAMP accumulation with an EC50 of 6.6±2.7 μM and an Emax of 31%±2%, whereas for the A1 agonist, N6-cyclopentyladenosine (CPA, 10-150 nM), an EC50 of 35±19 nM, and an Emax of 29%±5 were obtained. The combined inhibitory effect of WIN55212-2 (30 μM) and CPA (100 nM) on cAMP accumulation was 41%±6% (n=4), which did not differ (P>0.7) from the sum of the individual effects of each agonist (43%±8%) but was different (P<0.05) from the effects of CPA or WIN55212-2 alone. Preincubation with CPA (100 nM) for 95 min caused desensitization of adenosine A1 activity, which did not modify the effect of WIN55212-2 (30 μM) on cAMP accumulation. In conclusion, the combined effect of CB1 and A1 receptors on cAMP formation is additive and CB1 receptor activity is not affected by short-term A1 receptor desensitization.

  18. Phosphazene additives

    DOEpatents

    Harrup, Mason K; Rollins, Harry W

    2013-11-26

    An additive comprising a phosphazene compound that has at least two reactive functional groups and at least one capping functional group bonded to phosphorus atoms of the phosphazene compound. One of the at least two reactive functional groups is configured to react with cellulose and the other of the at least two reactive functional groups is configured to react with a resin, such as an amine resin of a polycarboxylic acid resin. The at least one capping functional group is selected from the group consisting of a short chain ether group, an alkoxy group, or an aryloxy group. Also disclosed are an additive-resin admixture, a method of treating a wood product, and a wood product.

  19. Potlining Additives

    SciTech Connect

    Rudolf Keller

    2004-08-10

    In this project, a concept to improve the performance of aluminum production cells by introducing potlining additives was examined and tested. Boron oxide was added to cathode blocks, and titanium was dissolved in the metal pool; this resulted in the formation of titanium diboride and caused the molten aluminum to wet the carbonaceous cathode surface. Such wetting reportedly leads to operational improvements and extended cell life. In addition, boron oxide suppresses cyanide formation. This final report presents and discusses the results of this project. Substantial economic benefits for the practical implementation of the technology are projected, especially for modern cells with graphitized blocks. For example, with an energy savings of about 5% and an increase in pot life from 1500 to 2500 days, a cost savings of $ 0.023 per pound of aluminum produced is projected for a 200 kA pot.

  20. Classification of red variables

    NASA Technical Reports Server (NTRS)

    Mattei, Janet A.; Foster, Grant; Hurwitz, Leora A.; Malatesta, Kerriann H.; Willson, Lee Anne; Mennessier, Marie-Odile

    1997-01-01

    Red variables are traditionally classified into Mira, semiregular (SR), and slow irregular (L) variables. The Mira variables are the best defined subgroup, whereas SR and L stars are more numerous. The SR subgroup is additionally subdivided into: SRa variables, which feature regular variability with smaller pulsation amplitudes than Miras; SRb variables, which are less regular; SRc variables, which are more luminous; and SRd variables, which are warmer. Relationships within each group are not clear. An analysis of long-term American Association of Variable Star Observers (AAVSP) light curves is reported on. It is found that Mira-type variables are clearly different and distinguishable from SR variables. Similarly, M-type Miras and C-type Miras feature different light curve properties. The M-Miras form a homogeneous group. The pulsations of SR variables are unstable.

  1. Independent Peer Reviews

    SciTech Connect

    2012-03-16

    Independent Assessments: DOE's Systems Integrator convenes independent technical reviews to gauge progress toward meeting specific technical targets and to provide technical information necessary for key decisions.

  2. Clinical and acoustical variability in hypokinetic dysarthria

    SciTech Connect

    Metter, E.J.; Hanson, W.R.

    1986-10-01

    Ten male patients with parkinsonism secondary to Parkinson's disease or progressive supranuclear palsy had clinical neurological, speech, and acoustical speech evaluations. In addition, seven of the patients were evaluated by x-ray computed tomography (CT) and (F-18)-fluorodeoxyglucose (FDG) positron emission tomography (PET). Extensive variability of speech features, both clinical and acoustical, were found and seemed to be independent of the severity of any parkinsonian sign, CT, or FDG PET. In addition, little relationship existed between the variability across each measured speech feature. What appeared to be important for the appearance of abnormal acoustic measures was the degree of overall severity of the dysarthria. These observations suggest that a better understanding of hypokinetic dysarthria may result from more extensive examination of the variability between patients. Emphasizing a specific feature such as rapid speaking rate in characterizing hypokinetic dysarthria focuses on a single and inconstant finding in a complex speech pattern.

  3. Mediator and moderator variables in nursing research: conceptual and statistical differences.

    PubMed

    Bennett, J A

    2000-10-01

    Mediators and moderators are variables that affect the association between an independent variable and an outcome variable. Mediators provide additional information about how or why two variables are strongly associated. In contrast, moderators explain the circumstances that cause a weak or ambiguous association between two variables that were expected to have a strong relationship. Mediators and moderators are often overlooked in research designs, or the terms are used incorrectly. This article summarizes the conceptual differences between mediators and moderators. The statistical analysis of moderators and mediators in multiple regression is briefly described and two examples are presented.

  4. Spatial Variance in Resting fMRI Networks of Schizophrenia Patients: An Independent Vector Analysis.

    PubMed

    Gopal, Shruti; Miller, Robyn L; Michael, Andrew; Adali, Tulay; Cetin, Mustafa; Rachakonda, Srinivas; Bustillo, Juan R; Cahill, Nathan; Baum, Stefi A; Calhoun, Vince D

    2016-01-01

    Spatial variability in resting functional MRI (fMRI) brain networks has not been well studied in schizophrenia, a disease known for both neurodevelopmental and widespread anatomic changes. Motivated by abundant evidence of neuroanatomical variability from previous studies of schizophrenia, we draw upon a relatively new approach called independent vector analysis (IVA) to assess this variability in resting fMRI networks. IVA is a blind-source separation algorithm, which segregates fMRI data into temporally coherent but spatially independent networks and has been shown to be especially good at capturing spatial variability among subjects in the extracted networks. We introduce several new ways to quantify differences in variability of IVA-derived networks between schizophrenia patients (SZs = 82) and healthy controls (HCs = 89). Voxelwise amplitude analyses showed significant group differences in the spatial maps of auditory cortex, the basal ganglia, the sensorimotor network, and visual cortex. Tests for differences (HC-SZ) in the spatial variability maps suggest, that at rest, SZs exhibit more activity within externally focused sensory and integrative network and less activity in the default mode network thought to be related to internal reflection. Additionally, tests for difference of variance between groups further emphasize that SZs exhibit greater network variability. These results, consistent with our prediction of increased spatial variability within SZs, enhance our understanding of the disease and suggest that it is not just the amplitude of connectivity that is different in schizophrenia, but also the consistency in spatial connectivity patterns across subjects. PMID:26106217

  5. An independent Cepheid distance scale: Current status

    NASA Technical Reports Server (NTRS)

    Barnes, T. G., III

    1980-01-01

    An independent distance scale for Cepheid variables is discussed. The apparent magnitude and the visual surface brightness, inferred from an appropriate color index, are used to determine the angular diameter variation of the Cepheid. When combined with the linear displacement curve obtained from the integrated radial velocity curve, the distance and linear radius are determined. The attractiveness of the method is its complete independence of all other stellar distance scales, even though a number of practical difficulties currently exist in implementing the technique.

  6. Fostering Musical Independence

    ERIC Educational Resources Information Center

    Shieh, Eric; Allsup, Randall Everett

    2016-01-01

    Musical independence has always been an essential aim of musical instruction. But this objective can refer to everything from high levels of musical expertise to more student choice in the classroom. While most conceptualizations of musical independence emphasize the demonstration of knowledge and skills within particular music traditions, this…

  7. Independent vs. Laboratory Papers.

    ERIC Educational Resources Information Center

    Wilson, Clint C., II

    1981-01-01

    Comparisons of independent and laboratory newspapers at selected California colleges indicated that (1) the independent newspapers were superior in editorial opinion and leadership characteristics; (2) the laboratory newspapers made better use of photography, art, and graphics; and (3) professional journalists highly rated their laboratory…

  8. Independence of Internal Auditors.

    ERIC Educational Resources Information Center

    Montondon, Lucille; Meixner, Wilda F.

    1993-01-01

    A survey of 288 college and university auditors investigated patterns in their appointment, reporting, and supervisory practices as indicators of independence and objectivity. Results indicate a weakness in the positioning of internal auditing within institutions, possibly compromising auditor independence. Because the auditing function is…

  9. American Independence. Fifth Grade.

    ERIC Educational Resources Information Center

    Crosby, Annette

    This fifth grade teaching unit covers early conflicts between the American colonies and Britain, battles of the American Revolutionary War, and the Declaration of Independence. Knowledge goals address the pre-revolutionary acts enforced by the British, the concepts of conflict and independence, and the major events and significant people from the…

  10. Ischemic changes on rubidium-82 positron emission tomography imaging are associated with left ventricular functional and volumetric change independent of metabolic properties and echocardiographic functional variables in ischemic cardiomyopathy.

    PubMed

    Wong, Raymond C; Cerqueira, Manuel D; Brunken, Richard C

    2012-08-01

    Positron emission tomography (PET) imaging allows identification of stress-induced ischemia and myocardial viability in patients with ischemic cardiomyopathy. We assessed the left ventricular (LV) functional response to vasodilator stress in patients with advanced ischemic cardiomyopathy undergoing pharmacologic stress (PET) perfusion and metabolic imaging. Additionally, we aimed to determine if mitral regurgitation (MR), right ventricular (RV) dysfunction and diastolic function influenced the observed LV responses to pharmacologic stress. In 161 patients (81% men; 65 ± 13 years), PET and echocardiography were performed within a week for noninvasive evaluation of myocardial ischemia and viability (scored using 17-segment model), as well as ventricular and valvular function. Patients were stratified based on ischemic defects in any segments versus hibernation/scar defects only. The LV volumes, EF by gating and transient ischemic dilatation (TID) index were generated automatically. Wall thickening (WT) scores were determined visually. The subgroup with reversible/ischemic segments on PET imaging (N = 55) exhibited greater end-systolic (ESV) and end-diastolic volume (EDV) enlargement during stress (13 ± 22 and 16 ± 43 ml increase respectively, vs. 0 ± 18 ml [P < 0.0001] and 2 ± 24 ml [P = 0.01]), a decrease in LVEF during stress (mean -3% vs. +2%), and greater TID indices (mean 1.13 ± 0.18 vs. 1.02 ± 0.12) compared to hibernation/scar only (N = 92). In addition, mean WT scores during stress declined significantly only in the ischemic subgroup (P < 0.0001 for regional LAD, non-LAD and global wall thickening scores). The prevalence and the severity of MR and RV dysfunction did not differ between groups. By univariate analysis, global and LAD territory segmental ischemia, global sum stress score (SSS), TID index, resting EF, ESV enlargement during stress, as well as global WT changes correlated with post-stress LVEF decline. Multivariate predictors included SSS

  11. Charter School Parents and Their Perceptions of Independent Schools

    ERIC Educational Resources Information Center

    Torres, Amada

    2014-01-01

    Given that independent schools have started to face competition from charter schools, the National Association of Independent Schools (NAIS) commissioned a study with current and prospective charter school parents to determine their perceptions of charter vs. independent schools, assess the relative impact of the variables that affect their school…

  12. Gait variability and disability in multiple sclerosis.

    PubMed

    Socie, Michael J; Motl, Robert W; Pula, John H; Sandroff, Brian M; Sosnoff, Jacob J

    2013-05-01

    Gait variability is clinically relevant in some populations, but there is limited documentation of gait variability in persons with multiple sclerosis (MS). This investigation examined average and variability of spatiotemporal gait parameters in persons with MS and healthy controls and subsequent associations with disability status. 88 individuals with MS (age 52.4±11.1) and 20 healthy controls (age 50.9±8.7) performed two self-paced walking trials on a 7.9-m electronic walkway to determine gait parameters. Disability was indexed by the Expanded Disability Status Scale (EDSS) and ranged between 2.5 and 6.5. Gait variability was indexed by standard deviation (SD) and coefficient of variation (CV=SD/mean) of step time, step length, and step width. Average gait parameters were significantly correlated with EDSS (ρ=0.756-0.609) and were significantly different in individuals with MS compared to controls (p≤0.002). Also, step length (p<0.001) and step time (p<0.001) variability were both significantly greater in MS compared to controls. EDSS was positively correlated with step length variability and individuals with MS who used assistive devices to walk had significantly greater step length variability than those who walked independently (p's<.05). EDSS was correlated with step time and length variability even when age was taken into account. Additionally, Fisher's z test of partial correlations revealed that average gait parameters were more closely related to disability status than gait variability in individuals with MS. This suggests that focusing on average gait parameters may be more important than variability in therapeutic interventions in MS.

  13. Response variability of marmoset parvocellular neurons.

    PubMed

    Victor, J D; Blessing, E M; Forte, J D; Buzás, P; Martin, P R

    2007-02-15

    This study concerns the properties of neurons carrying signals for colour vision in primates. We investigated the variability of responses of individual parvocellular lateral geniculate neurons of dichromatic and trichromatic marmosets to drifting sinusoidal luminance and chromatic gratings. Response variability was quantified by the cycle-to-cycle variation in Fourier components of the response. Averaged across the population, the variability at low contrasts was greater than predicted by a Poisson process, and at high contrasts the responses were approximately 40% more variable than responses at low contrasts. The contrast-dependent increase in variability was nevertheless below that expected from the increase in firing rate. Variability falls below the Poisson prediction at high contrast, and intrinsic variability of the spike train decreases as contrast increases. Thus, while deeply modulated responses in parvocellular cells have a larger absolute variability than weakly modulated ones, they have a more favourable signal: noise ratio than predicted by a Poisson process. Similar results were obtained from a small sample of magnocellular and koniocellular ('blue-on') neurons. For parvocellular neurons with pronounced colour opponency, chromatic responses were, on average, less variable (10-15%, p<0.01) than luminance responses of equal magnitude. Conversely, non-opponent parvocellular neurons showed the opposite tendency. This is consistent with a supra-additive noise source prior to combination of cone signals. In summary, though variability of parvocellular neurons is largely independent of the way in which they combine cone signals, the noise characteristics of retinal circuitry may augment specialization of parvocellular neurons to signal luminance or chromatic contrast. PMID:17124265

  14. Evaluating Reanalysis - Independent Observations and Observation Independence

    NASA Astrophysics Data System (ADS)

    Wahl, S.; Bollmeyer, C.; Danek, C.; Friederichs, P.; Keller, J. D.; Ohlwein, C.

    2014-12-01

    Reanalyses on global to regional scales are widely used for validation of meteorological or hydrological models and for many climate applications. However, the evaluation of the reanalyses itself is still a crucial task. A major challenge is the lack of independent observations, since most of the available observational data is already included, e. g. by the data assimilation scheme. Here, we focus on the evaluation of dynamical reanalyses which are obtained by using numerical weather prediction models with a fixed data assimilation scheme. Precipitation is generally not assimilated in dynamical reanalyses (except for e.g. latent heat nudging) and thereby provides valuable data for the evaluation of reanalysis. Since precipitation results from the complex dynamical and microphysical atmospheric processes, an accurate representation of precipitation is often used as an indicator for a good model performance. Here, we use independent observations of daily precipitation accumulations from European rain gauges (E-OBS) of the years 2008 and 2009 for the intercomparison of various regional reanalyses products for the European CORDEX domain (Hirlam reanalysis at 0.2°, Metoffice UM reanalysis at 0.11°, COSMO reanalysis at 0.055°). This allows for assessing the benefits of increased horizontal resolution compared to global reanalyses. Furthermore, the effect of latent heat nudging (assimilation of radar-derived rain rates) is investigated using an experimental setup of the COSMO reanalysis with 6km and 2km resolution for summer 2011. Further, we present an observation independent evaluation based on kinetic energy spectra. Such spectra should follow a k-3 dependence of the wave number k for the larger scale, and a k-5/3 dependence on the mesoscale. We compare the spectra of the aforementioned regional reanalyses in order to investigate the general capability of the reanalyses to resolve events on the mesoscale (e.g. effective resolution). The intercomparison and

  15. Chandra Independently Determines Hubble Constant

    NASA Astrophysics Data System (ADS)

    2006-08-01

    A critically important number that specifies the expansion rate of the Universe, the so-called Hubble constant, has been independently determined using NASA's Chandra X-ray Observatory. This new value matches recent measurements using other methods and extends their validity to greater distances, thus allowing astronomers to probe earlier epochs in the evolution of the Universe. "The reason this result is so significant is that we need the Hubble constant to tell us the size of the Universe, its age, and how much matter it contains," said Max Bonamente from the University of Alabama in Huntsville and NASA's Marshall Space Flight Center (MSFC) in Huntsville, Ala., lead author on the paper describing the results. "Astronomers absolutely need to trust this number because we use it for countless calculations." Illustration of Sunyaev-Zeldovich Effect Illustration of Sunyaev-Zeldovich Effect The Hubble constant is calculated by measuring the speed at which objects are moving away from us and dividing by their distance. Most of the previous attempts to determine the Hubble constant have involved using a multi-step, or distance ladder, approach in which the distance to nearby galaxies is used as the basis for determining greater distances. The most common approach has been to use a well-studied type of pulsating star known as a Cepheid variable, in conjunction with more distant supernovae to trace distances across the Universe. Scientists using this method and observations from the Hubble Space Telescope were able to measure the Hubble constant to within 10%. However, only independent checks would give them the confidence they desired, considering that much of our understanding of the Universe hangs in the balance. Chandra X-ray Image of MACS J1149.5+223 Chandra X-ray Image of MACS J1149.5+223 By combining X-ray data from Chandra with radio observations of galaxy clusters, the team determined the distances to 38 galaxy clusters ranging from 1.4 billion to 9.3 billion

  16. Data Machine Independence

    1994-12-30

    Data-machine independence achieved by using four technologies (ASN.1, XDR, SDS, and ZEBRA) has been evaluated by encoding two different applications in each of the above; and their results compared against the standard programming method using C.

  17. Media independent interface

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The work done on the Media Independent Interface (MII) Interface Control Document (ICD) program is described and recommendations based on it were made. Explanations and rationale for the content of the ICD itself are presented.

  18. Long-term variability of aerosol optical thickness in Eastern Europe over 2001-2014 according to the measurements at the Moscow MSU MO AERONET site with additional cloud and NO2 correction

    NASA Astrophysics Data System (ADS)

    Chubarova, N. Y.; Poliukhov, A. A.; Gorlova, I. D.

    2015-07-01

    The aerosol properties of the atmosphere were obtained within the framework of the AERONET program at the Moscow State University Meteorological Observatory (Moscow MSU MO) over 2001-2014 period. The quality data control has revealed the necessity of their additional cloud and NO2 correction. The application of cloud correction according to hourly visual cloud observations provides a decrease in average aerosol optical thickness (AOT) at 500 nm of up to 0.03 compared with the standard dataset. We also show that the additional NO2 correction of the AERONET data is needed in large megalopolis, like Moscow, with 12 million residents and the NOx emission rates of about 100 kt yr-1. According to the developed method we estimated monthly mean NO2 content, which provides an additional decrease of 0.01 for AOT at 340 nm, and of about 0.015 - for AOT at 380 and 440 nm. The ratios of NO2 optical thickness to AOT at 380 and 440 nm are about 5-6 % in summer and reach 15-20 % in winter when both factors have similar effects on UV irradiance. Seasonal cycle of AOT at 500 nm is characterized by a noticeable summer and spring maxima, and minimum in winter conditions, changing from 0.08 in December and January up to 0.3 in August. The application of the additional cloud correction removes a local AOT maximum in February, and lowered the December artificial high AOT values. The pronounced negative AOT trends of about -1-5 % yr-1 have been obtained for most months, which could be attributed to the negative trends in emissions (E) of different aerosol precursors of about 116 Gg yr-2 in ESOx, 78 Gg yr-2 in ENMVOC, and 272 Gg yr-2 in ECO over European territory of Russia. No influence of natural factors on temporal AOT variations has been revealed.

  19. Spontaneous neuronal burst discharges as dependent and independent variables in the maturation of cerebral cortex tissue cultured in vitro: a review of activity-dependent studies in live 'model' systems for the development of intrinsically generated bioelectric slow-wave sleep patterns.

    PubMed

    Corner, Michael A

    2008-11-01

    A survey is presented of recent experiments which utilize spontaneous neuronal spike trains as dependent and/or independent variables in developing cerebral cortex cultures when synaptic transmission is interfered with for varying periods of time. Special attention is given to current difficulties in selecting suitable preparations for carrying out biologically relevant developmental studies, and in applying spike-train analysis methods with sufficient resolution to detect activity-dependent age and treatment effects. A hierarchy of synchronized nested burst discharges which approximate early slow-wave sleep patterns in the intact organism is established as a stable basis for isolated cortex function. The complexity of reported long- and short-term homeostatic responses to experimental interference with synaptic transmission is reviewed, and the crucial role played by intrinsically generated bioelectric activity in the maturation of cortical networks is emphasized.

  20. Gasoline additives, emissions, and performance

    SciTech Connect

    1995-12-31

    The papers included in this publication deal with the influence of fuel, additive, and hardware changes on a variety of vehicle performance characteristics. Advanced techniques for measuring these performance parameters are also described. Contents include: Fleet test evaluation of gasoline additives for intake valve and combustion chamber deposit clean up; A technique for evaluating octane requirement additives in modern engines on dynamometer test stands; A fleet test of two additive technologies comparing their effects on tailpipe emissions; Investigation into the vehicle exhaust emissions of high percentage ethanol blends; Variability in hydrocarbon speciation measurements at low emission (ULEV) levels; and more.

  1. Inside of the Linear Relation between Dependent and Independent Variables

    PubMed Central

    Jäntschi, Lorentz; Pruteanu, Lavinia L.; Cozma, Alina C.; Bolboacă, Sorana D.

    2015-01-01

    Simple and multiple linear regression analyses are statistical methods used to investigate the link between activity/property of active compounds and the structural chemical features. One assumption of the linear regression is that the errors follow a normal distribution. This paper introduced a new approach to solving the simple linear regression in which no assumptions about the distribution of the errors are made. The proposed approach maximizes the probability of observing the event according to the random error. The use of the proposed approach is illustrated in ten classes of compounds with different activities or properties. The proposed method proved reliable and was showed to fit properly the observed data compared to the convenient approach of normal distribution of the errors. PMID:26101543

  2. Inside of the Linear Relation between Dependent and Independent Variables.

    PubMed

    Jäntschi, Lorentz; Pruteanu, Lavinia L; Cozma, Alina C; Bolboacă, Sorana D

    2015-01-01

    Simple and multiple linear regression analyses are statistical methods used to investigate the link between activity/property of active compounds and the structural chemical features. One assumption of the linear regression is that the errors follow a normal distribution. This paper introduced a new approach to solving the simple linear regression in which no assumptions about the distribution of the errors are made. The proposed approach maximizes the probability of observing the event according to the random error. The use of the proposed approach is illustrated in ten classes of compounds with different activities or properties. The proposed method proved reliable and was showed to fit properly the observed data compared to the convenient approach of normal distribution of the errors.

  3. Independent NOAA considered

    NASA Astrophysics Data System (ADS)

    Richman, Barbara T.

    A proposal to pull the National Oceanic and Atmospheric Administration (NOAA) out of the Department of Commerce and make it an independent agency was the subject of a recent congressional hearing. Supporters within the science community and in Congress said that an independent NOAA will benefit by being more visible and by not being tied to a cabinet-level department whose main concerns lie elsewhere. The proposal's critics, however, cautioned that making NOAA independent could make it even more vulnerable to the budget axe and would sever the agency's direct access to the President.The separation of NOAA from Commerce was contained in a June 1 proposal by President Ronald Reagan that also called for all federal trade functions under the Department of Commerce to be reorganized into a new Department of International Trade and Industry (DITI).

  4. Independent technical review, handbook

    SciTech Connect

    Not Available

    1994-02-01

    Purpose Provide an independent engineering review of the major projects being funded by the Department of Energy, Office of Environmental Restoration and Waste Management. The independent engineering review will address questions of whether the engineering practice is sufficiently developed to a point where a major project can be executed without significant technical problems. The independent review will focus on questions related to: (1) Adequacy of development of the technical base of understanding; (2) Status of development and availability of technology among the various alternatives; (3) Status and availability of the industrial infrastructure to support project design, equipment fabrication, facility construction, and process and program/project operation; (4) Adequacy of the design effort to provide a sound foundation to support execution of project; (5) Ability of the organization to fully integrate the system, and direct, manage, and control the execution of a complex major project.

  5. Response-independent milk delivery enhances persistence of pellet-reinforced lever pressing by rats.

    PubMed Central

    Grimes, J A; Shull, R L

    2001-01-01

    If, during training, one stimulus is correlated with a higher rate of reinforcement than another, responding will be more resistant to extinction in the presence of that higher rate signal, even if many of the reinforcers have been presented independently of responding. For the present study we asked if the response-independent reinforcers must be the same as the response-dependent reinforcers to enhance the response's persistence. Twelve Long-Evans hooded rats obtained 45-mg food pellets by lever pressing (variable-interval 100-s schedules) in the presence of two discriminative stimuli (blinking vs. steady lights) that alternated every minute during daily sessions. Also, in the presence of one of the stimuli (counterbalanced across rats), the rats received additional response-independent deliveries of sweetened condensed milk (a variable-time schedule). Extinction sessions were exactly like training sessions except that neither pellets nor milk were presented. Lever pressing was more resistant to extinction in the presence of the milk-correlated stimulus when (a) the size of the milk deliveries during training (under a variable-time 30 s schedule) was 0.04 ml (vs. 0.01 ml) and (b) 120-s or 240-s blackouts separated components. Response-independent reinforcers do not have to be the same as the response-dependent reinforcers to enhance persistence. PMID:11599638

  6. Independence and Survival.

    ERIC Educational Resources Information Center

    James, H. Thomas

    Independent schools that are of viable size, well managed, and strategically located to meet competition will survive and prosper past the current financial crisis. We live in a complex technological society with insatiable demands for knowledgeable people to keep it running. The future will be marked by the orderly selection of qualified people,…

  7. Independence, Disengagement, and Discipline

    ERIC Educational Resources Information Center

    Rubin, Ron

    2012-01-01

    School disengagement is linked to a lack of opportunities for students to fulfill their needs for independence and self-determination. Young people have little say about what, when, where, and how they will learn, the criteria used to assess their success, and the content of school and classroom rules. Traditional behavior management discourages…

  8. Caring about Independent Lives

    ERIC Educational Resources Information Center

    Christensen, Karen

    2010-01-01

    With the rhetoric of independence, new cash for care systems were introduced in many developed welfare states at the end of the 20th century. These systems allow local authorities to pay people who are eligible for community care services directly, to enable them to employ their own careworkers. Despite the obvious importance of the careworker's…

  9. Postcard from Independence, Mo.

    ERIC Educational Resources Information Center

    Archer, Jeff

    2004-01-01

    This article reports results showing that the Independence, Missori school district failed to meet almost every one of its improvement goals under the No Child Left Behind Act. The state accreditation system stresses improvement over past scores, while the federal law demands specified amounts of annual progress toward the ultimate goal of 100…

  10. Independent School Governance.

    ERIC Educational Resources Information Center

    Beavis, Allan K.

    Findings of a study that examined the role of the governing body in the independent school's self-renewing processes are presented in this paper. From the holistic paradigm, the school is viewed as a self-renewing system that is able to maintain its identity despite environmental changes through existing structures that define and create…

  11. Why Additional Presentations Help Identify a Stimulus

    ERIC Educational Resources Information Center

    Guest, Duncan; Kent, Christopher; Adelman, James S.

    2010-01-01

    Nosofsky (1983) reported that additional stimulus presentations within a trial increase discriminability in absolute identification, suggesting that each presentation creates an independent stimulus representation, but it remains unclear whether exposure duration or the formation of independent representations improves discrimination in such…

  12. Multi-Wheat-Model Ensemble Responses to Interannual Climate Variability

    NASA Technical Reports Server (NTRS)

    Ruane, Alex C.; Hudson, Nicholas I.; Asseng, Senthold; Camarrano, Davide; Ewert, Frank; Martre, Pierre; Boote, Kenneth J.; Thorburn, Peter J.; Aggarwal, Pramod K.; Angulo, Carlos

    2016-01-01

    We compare 27 wheat models' yield responses to interannual climate variability, analyzed at locations in Argentina, Australia, India, and The Netherlands as part of the Agricultural Model Intercomparison and Improvement Project (AgMIP) Wheat Pilot. Each model simulated 1981e2010 grain yield, and we evaluate results against the interannual variability of growing season temperature, precipitation, and solar radiation. The amount of information used for calibration has only a minor effect on most models' climate response, and even small multi-model ensembles prove beneficial. Wheat model clusters reveal common characteristics of yield response to climate; however models rarely share the same cluster at all four sites indicating substantial independence. Only a weak relationship (R2 0.24) was found between the models' sensitivities to interannual temperature variability and their response to long-termwarming, suggesting that additional processes differentiate climate change impacts from observed climate variability analogs and motivating continuing analysis and model development efforts.

  13. Interval arithmetic operations for uncertainty analysis with correlated interval variables

    NASA Astrophysics Data System (ADS)

    Jiang, Chao; Fu, Chun-Ming; Ni, Bing-Yu; Han, Xu

    2016-08-01

    A new interval arithmetic method is proposed to solve interval functions with correlated intervals through which the overestimation problem existing in interval analysis could be significantly alleviated. The correlation between interval parameters is defined by the multidimensional parallelepiped model which is convenient to describe the correlative and independent interval variables in a unified framework. The original interval variables with correlation are transformed into the standard space without correlation, and then the relationship between the original variables and the standard interval variables is obtained. The expressions of four basic interval arithmetic operations, namely addition, subtraction, multiplication, and division, are given in the standard space. Finally, several numerical examples and a two-step bar are used to demonstrate the effectiveness of the proposed method.

  14. Modes of independence while informal caregiving.

    PubMed

    Tellioğlu, Hilda; Hensely-Schinkinger, Susanne; Pinatti De Carvalho, Aparecido Fabiano

    2015-01-01

    This paper is about understanding and conceptualizing the notion of independence in the context of caregiving. Based on the current studies and on our ethnographic and design research in an AAL project (TOPIC) we introduce a model of independence consisting of four dimensions: action, finance, decision, and emotion. These interrelated dimensions are described and discussed in the setting of informal caregiving. Some additional examples are shown to illustrate how to reduce the dependence of informal caregivers before concluding the paper. PMID:26294578

  15. Motivated independence? Implicit party identity predicts political judgments among self-proclaimed Independents.

    PubMed

    Hawkins, Carlee Beth; Nosek, Brian A

    2012-11-01

    Reporting an Independent political identity does not guarantee the absence of partisanship. Independents demonstrated considerable variability in relative identification with Republicans versus Democrats as measured by an Implicit Association Test (IAT; M = 0.10, SD = 0.47). To test whether this variation predicted political judgment, participants read a newspaper article describing two competing welfare (Study 1) or special education (Study 2) policies. The authors manipulated which policy was proposed by which party. Among self-proclaimed Independents, those who were implicitly Democratic preferred the liberal welfare plan, and those who were implicitly Republican preferred the conservative welfare plan. Regardless of the policy details, these implicit partisans preferred the policy proposed by "their" party, and this effect occurred more strongly for implicit than explicit plan preference. The authors suggest that implicitly partisan Independents may consciously override some partisan influence when making explicit political judgments, and Independents may identify as such to appear objective even when they are not.

  16. Variables associated with upper extremity function in patients with Duchenne muscular dystrophy.

    PubMed

    Janssen, Mariska M H P; Hendriks, Jan C M; Geurts, Alexander C H; de Groot, Imelda J M

    2016-09-01

    Preserving upper extremity (UE) function in patients with Duchenne muscular dystrophy (DMD) is extremely important as it is related to independence and quality of life. For clinical decision making, knowledge of variables associated with UE function is necessary. This knowledge is, however, limited. Therefore, this study aims to gain more insight into the variables associated with UE function in DMD. Data from an international web-based questionnaire on UE function, obtained from 213 DMD patients, were used. Six dependent variables regarding UE function were used in multivariable linear regression analyses. In addition, 26 independent variables regarding patient characteristics, medication, therapy, supportive aids, pain, stiffness and participation were used. Twelve independent variables showed a significant relation to UE function. Variables with a negative relation to UE function were: later disease stage, occurrence of scoliosis, higher age, use of UE splints, more frequent stiffness complaints, more limitations due to stiffness, more frequent elbow pain, and having physical therapy. A positive relation with UE function was seen for going to school or work, use of corticosteroids, higher BMI, and higher age at diagnosis. These variables explained 56-81 % of the variation of the different measures of UE function. Knowledge of variables associated with UE function is very important in the clinical management of DMD patients. The results of this study suggest that corticosteroid use and participation in school and work related activities are positively related to UE function in DMD patients, as well as reducing pain and stiffness and preventing scoliosis.

  17. Variables associated with upper extremity function in patients with Duchenne muscular dystrophy.

    PubMed

    Janssen, Mariska M H P; Hendriks, Jan C M; Geurts, Alexander C H; de Groot, Imelda J M

    2016-09-01

    Preserving upper extremity (UE) function in patients with Duchenne muscular dystrophy (DMD) is extremely important as it is related to independence and quality of life. For clinical decision making, knowledge of variables associated with UE function is necessary. This knowledge is, however, limited. Therefore, this study aims to gain more insight into the variables associated with UE function in DMD. Data from an international web-based questionnaire on UE function, obtained from 213 DMD patients, were used. Six dependent variables regarding UE function were used in multivariable linear regression analyses. In addition, 26 independent variables regarding patient characteristics, medication, therapy, supportive aids, pain, stiffness and participation were used. Twelve independent variables showed a significant relation to UE function. Variables with a negative relation to UE function were: later disease stage, occurrence of scoliosis, higher age, use of UE splints, more frequent stiffness complaints, more limitations due to stiffness, more frequent elbow pain, and having physical therapy. A positive relation with UE function was seen for going to school or work, use of corticosteroids, higher BMI, and higher age at diagnosis. These variables explained 56-81 % of the variation of the different measures of UE function. Knowledge of variables associated with UE function is very important in the clinical management of DMD patients. The results of this study suggest that corticosteroid use and participation in school and work related activities are positively related to UE function in DMD patients, as well as reducing pain and stiffness and preventing scoliosis. PMID:27314968

  18. Agent independent task planning

    NASA Technical Reports Server (NTRS)

    Davis, William S.

    1990-01-01

    Agent-Independent Planning is a technique that allows the construction of activity plans without regard to the agent that will perform them. Once generated, a plan is then validated and translated into instructions for a particular agent, whether a robot, crewmember, or software-based control system. Because Space Station Freedom (SSF) is planned for orbital operations for approximately thirty years, it will almost certainly experience numerous enhancements and upgrades, including upgrades in robotic manipulators. Agent-Independent Planning provides the capability to construct plans for SSF operations, independent of specific robotic systems, by combining techniques of object oriented modeling, nonlinear planning and temporal logic. Since a plan is validated using the physical and functional models of a particular agent, new robotic systems can be developed and integrated with existing operations in a robust manner. This technique also provides the capability to generate plans for crewmembers with varying skill levels, and later apply these same plans to more sophisticated robotic manipulators made available by evolutions in technology.

  19. International exploration by independents

    SciTech Connect

    Bertagne, R.G. )

    1991-03-01

    Recent industry trends indicate that the smaller US independents are looking at foreign exploration opportunities as one of the alternatives for growth in the new age of exploration. It is usually accepted that foreign finding costs per barrel are substantially lower than domestic because of the large reserve potential of international plays. To get involved overseas requires, however, an adaptation to different cultural, financial, legal, operational, and political conditions. Generally foreign exploration proceeds at a slower pace than domestic because concessions are granted by the government, or are explored in partnership with the national oil company. First, a mid- to long-term strategy, tailored to the goals and the financial capabilities of the company, must be prepared; it must be followed by an ongoing evaluation of quality prospects in various sedimentary basins, and a careful planning and conduct of the operations. To successfully explore overseas also requires the presence on the team of a minimum number of explorationists and engineers thoroughly familiar with the various exploratory and operational aspects of foreign work, having had a considerable amount of onsite experience in various geographical and climatic environments. Independents that are best suited for foreign expansion are those that have been financially successful domestically, and have a good discovery track record. When properly approached foreign exploration is well within the reach of smaller US independents and presents essentially no greater risk than domestic exploration; the reward, however, can be much larger and can catapult the company into the big leagues.

  20. International exploration by independent

    SciTech Connect

    Bertragne, R.G.

    1992-04-01

    Recent industry trends indicate that the smaller U.S. independents are looking at foreign exploration opportunities as one of the alternatives for growth in the new age of exploration. Foreign finding costs per barrel usually are accepted to be substantially lower than domestic costs because of the large reserve potential of international plays. To get involved in overseas exploration, however, requires the explorationist to adapt to different cultural, financial, legal, operational, and political conditions. Generally, foreign exploration proceeds at a slower pace than domestic exploration because concessions are granted by a country's government, or are explored in partnership with a national oil company. First, the explorationist must prepare a mid- to long-term strategy, tailored to the goals and the financial capabilities of the company; next, is an ongoing evaluation of quality prospects in various sedimentary basins, and careful planning and conduct of the operations. To successfully explore overseas also requires the presence of a minimum number of explorationists and engineers thoroughly familiar with the various exploratory and operational aspects of foreign work. Ideally, these team members will have had a considerable amount of on-site experience in various countries and climates. Independents best suited for foreign expansion are those who have been financially successful in domestic exploration. When properly approached, foreign exploration is well within the reach of smaller U.S. independents, and presents essentially no greater risk than domestic exploration; however, the reward can be much larger and can catapult the company into the 'big leagues.'

  1. Compact programmable photonic variable delay devices

    NASA Technical Reports Server (NTRS)

    Yao, X. Steve (Inventor)

    1999-01-01

    Optical variable delay devices for providing variable true time delay to multiple optical beams simultaneously. A ladder-structured variable delay device comprises multiple basic building blocks stacked on top of each other resembling a ladder. Each basic building block has two polarization beamsplitters and a polarization rotator array arranged to form a trihedron; Controlling an array element of the polarization rotator array causes a beam passing through the array element either going up to a basic building block above it or reflect back towards a block below it. The beams going higher on the ladder experience longer optical path delay. An index-switched optical variable delay device comprises of many birefringent crystal segments connected with one another, with a polarization rotator array sandwiched between any two adjacent crystal segments. An array element in the polarization rotator array controls the polarization state of a beam passing through the element, causing the beam experience different refractive indices or path delays in the following crystal segment. By independently control each element in each polarization rotator array, variable optical path delays of each beam can be achieved. Finally, an index-switched variable delay device and a ladder-structured variable device are cascaded to form a new device which combines the advantages of the two individual devices. This programmable optic device has the properties of high packing density, low loss, easy fabrication, and virtually infinite bandwidth. The device is inherently two dimensional and has a packing density exceeding 25 lines/cm.sup.2. The delay resolution of the device is on the order of a femtosecond (one micron in space) and the total delay exceeds 10 nanosecond. In addition, the delay is reversible so that the same delay device can be used for both antenna transmitting and receiving.

  2. A generalized additive model for the spatial distribution of snowpack in the Spanish Pyrenees

    NASA Astrophysics Data System (ADS)

    López-Moreno, J. I.; Nogués-Bravo, D.

    2005-10-01

    A generalized additive model (GAM) was used to model the spatial distribution of snow depth in the central Spanish Pyrenees. Statistically significant non-linear relationships were found between distinct location and topographical variables and the average depth of the April snowpack at 76 snow poles from 1985 to 2000. The joint effect of the predictor variables explained more than 73% of the variance of the dependent variable. The performance of the model was assessed by applying a number of quantitative approaches to the residuals from a cross-validation test. The relatively low estimated errors and the possibility of understanding the processes that control snow accumulation, through the response curves of each independent variable, indicate that GAMs may be a useful tool for interpolating local snow depth or other climate parameters.

  3. Relative Reinforcer Rates and Magnitudes Do Not Control Concurrent Choice Independently

    ERIC Educational Resources Information Center

    Elliffe, Douglas; Davison, Michael; Landon, Jason

    2008-01-01

    One assumption of the matching approach to choice is that different independent variables control choice independently of each other. We tested this assumption for reinforcer rate and magnitude in an extensive parametric experiment. Five pigeons responded for food reinforcement on switching-key concurrent variable-interval variable-interval…

  4. Classification by Functional Ability for Independent Living. Research Supplement.

    ERIC Educational Resources Information Center

    Dunlap, William R.; Sands, Deanna Iceman

    1989-01-01

    A total of 274 British youth and adults with handicaps were administered the National Independent Living Skills assessment. Cluster analysis suggested that handicapped persons could be classified into four groups from lowest functioning to highest functioning, using independent living skills variables relating to living, work, and educational…

  5. Achievement Patterns of Students in an Elite, Male Independent School

    ERIC Educational Resources Information Center

    Trusty, Edward Maurice, Jr.

    2009-01-01

    There is an underlying assumption that regardless of student ethnicity, socio-economic status, or any other variable, elite, independent schools by mission and design are effective at producing successful students. This would cause some to conclude that all students enrolled in elite, independent schools perform similarly on all academic measures.…

  6. Cary Potter on Independent Education

    ERIC Educational Resources Information Center

    Potter, Cary

    1978-01-01

    Cary Potter was President of the National Association of Independent Schools from 1964-1978. As he leaves NAIS he gives his views on education, on independence, on the independent school, on public responsibility, on choice in a free society, on educational change, and on the need for collective action by independent schools. (Author/RK)

  7. Myth or Truth: Independence Day.

    ERIC Educational Resources Information Center

    Gardner, Traci

    Most Americans think of the Fourth of July as Independence Day, but is it really the day the U.S. declared and celebrated independence? By exploring myths and truths surrounding Independence Day, this lesson asks students to think critically about commonly believed stories regarding the beginning of the Revolutionary War and the Independence Day…

  8. Variable Order and Distributed Order Fractional Operators

    NASA Technical Reports Server (NTRS)

    Lorenzo, Carl F.; Hartley, Tom T.

    2002-01-01

    Many physical processes appear to exhibit fractional order behavior that may vary with time or space. The continuum of order in the fractional calculus allows the order of the fractional operator to be considered as a variable. This paper develops the concept of variable and distributed order fractional operators. Definitions based on the Riemann-Liouville definitions are introduced and behavior of the operators is studied. Several time domain definitions that assign different arguments to the order q in the Riemann-Liouville definition are introduced. For each of these definitions various characteristics are determined. These include: time invariance of the operator, operator initialization, physical realization, linearity, operational transforms. and memory characteristics of the defining kernels. A measure (m2) for memory retentiveness of the order history is introduced. A generalized linear argument for the order q allows the concept of "tailored" variable order fractional operators whose a, memory may be chosen for a particular application. Memory retentiveness (m2) and order dynamic behavior are investigated and applications are shown. The concept of distributed order operators where the order of the time based operator depends on an additional independent (spatial) variable is also forwarded. Several definitions and their Laplace transforms are developed, analysis methods with these operators are demonstrated, and examples shown. Finally operators of multivariable and distributed order are defined in their various applications are outlined.

  9. A Survey of Phase Variable Candidates of Human Locomotion

    PubMed Central

    Villarreal, Dario J.; Gregg, Robert D.

    2014-01-01

    Studies show that the human nervous system is able to parameterize gait cycle phase using sensory feedback. In the field of bipedal robots, the concept of a phase variable has been successfully used to mimic this behavior by parameterizing the gait cycle in a time-independent manner. This approach has been applied to control a powered transfemoral prosthetic leg, but the proposed phase variable was limited to the stance period of the prosthesis only. In order to achieve a more robust controller, we attempt to find a new phase variable that fully parameterizes the gait cycle of a prosthetic leg. The angle with respect to a global reference frame at the hip is able to monotonically parameterize both the stance and swing periods of the gait cycle. This survey looks at multiple phase variable candidates involving the hip angle with respect to a global reference frame across multiple tasks including level-ground walking, running, and stair negotiation. In particular, we propose a novel phase variable candidate that monotonically parameterizes the whole gait cycle across all tasks, and does so particularly well across level-ground walking. In addition to furthering the design of robust robotic prosthetic leg controllers, this survey could help neuroscientists and physicians study human locomotion across tasks from a time-independent perspective. PMID:25570873

  10. Frame independent cosmological perturbations

    SciTech Connect

    Prokopec, Tomislav; Weenink, Jan E-mail: j.g.weenink@uu.nl

    2013-09-01

    We compute the third order gauge invariant action for scalar-graviton interactions in the Jordan frame. We demonstrate that the gauge invariant action for scalar and tensor perturbations on one physical hypersurface only differs from that on another physical hypersurface via terms proportional to the equation of motion and boundary terms, such that the evolution of non-Gaussianity may be called unique. Moreover, we demonstrate that the gauge invariant curvature perturbation and graviton on uniform field hypersurfaces in the Jordan frame are equal to their counterparts in the Einstein frame. These frame independent perturbations are therefore particularly useful in relating results in different frames at the perturbative level. On the other hand, the field perturbation and graviton on uniform curvature hypersurfaces in the Jordan and Einstein frame are non-linearly related, as are their corresponding actions and n-point functions.

  11. Prioritizing Highway Safety Manual's crash prediction variables using boosted regression trees.

    PubMed

    Saha, Dibakar; Alluri, Priyanka; Gan, Albert

    2015-06-01

    The Highway Safety Manual (HSM) recommends using the empirical Bayes (EB) method with locally derived calibration factors to predict an agency's safety performance. However, the data needs for deriving these local calibration factors are significant, requiring very detailed roadway characteristics information. Many of the data variables identified in the HSM are currently unavailable in the states' databases. Moreover, the process of collecting and maintaining all the HSM data variables is cost-prohibitive. Prioritization of the variables based on their impact on crash predictions would, therefore, help to identify influential variables for which data could be collected and maintained for continued updates. This study aims to determine the impact of each independent variable identified in the HSM on crash predictions. A relatively recent data mining approach called boosted regression trees (BRT) is used to investigate the association between the variables and crash predictions. The BRT method can effectively handle different types of predictor variables, identify very complex and non-linear association among variables, and compute variable importance. Five years of crash data from 2008 to 2012 on two urban and suburban facility types, two-lane undivided arterials and four-lane divided arterials, were analyzed for estimating the influence of variables on crash predictions. Variables were found to exhibit non-linear and sometimes complex relationship to predicted crash counts. In addition, only a few variables were found to explain most of the variation in the crash data.

  12. Controlling variability.

    PubMed

    Sanger, Terence D

    2010-11-01

    In human motor control, there is uncertainty in both estimation of initial sensory state and prediction of the outcome of motor commands. With practice, increasing precision can often be achieved, but such precision incurs costs in time, effort, and neural resources. Therefore, motor planning must account for variability, uncertainty, and noise, not just at the endpoint of movement but throughout the movement. The author presents a mathematical basis for understanding the time course of uncertainty during movement. He shows that it is possible to achieve accurate control of the endpoint of a movement even with highly inaccurate and variable controllers. The results provide a first step toward a theory of optimal control for variable, uncertain, and noisy systems that must nevertheless accomplish real-world tasks reliably.

  13. Independence and symbolic independence of nonstationary heartbeat series during atrial fibrillation

    NASA Astrophysics Data System (ADS)

    Cammarota, Camillo; Rogora, Enrico

    2005-08-01

    Heartbeat intervals during atrial fibrillation are commonly believed to form a series of almost independent variables. The series extracted from 24 h Holter recordings show a nonstationary behavior. Because of nonstationarity it is difficult to give a quantitative measure of independence. In this paper, we use and compare two methods for this. The first is a classical method which models a nonstationary series using a linear Gaussian state space model. In this framework, the independence is tested on the stationary sequence of the residuals. The second method codes data into permutations and tests the uniformity of their distribution. This test assumes as null hypothesis a weaker form of independence which we call symbolic independence. We discuss some advantages of symbolic independence in the context of heartbeat series. We analyze the time series of heartbeat intervals from 24 h Holter recordings of nine subjects with chronic atrial fibrillation and find that the detrended series is a zero or one memory process for 83% of regular segments and is symbolically independent for 93% of segments.

  14. Which variability?

    PubMed

    Toraldo, Alessio; Luzzatti, Claudio

    2006-02-01

    Drai and Grodzinsky provide a valuable analysis that offers a way of disentangling the effects of Movement and Mood in agrammatic comprehension. However, their mathematical implementation (Beta model) hides theoretically relevant information, i.e., qualitative heterogeneities of performance within the patient sample. This heterogeneity is crucial in the variability debate.

  15. The semantic--procedural interface model of the self: the role of self-knowledge for context-dependent versus context-independent modes of thinking.

    PubMed

    Kühnen, U; Hannover, B; Schubert, B

    2001-03-01

    How do independent and interdependent self-construals affect cognition? The authors proposed the semantic-procedural interface model, which distinguishes 2 such mechanisms. In addition to semantic differences, different procedural modes of thinking are associated with independent and interdependent self-construals. Independent self-definitions coincide with the tendency to process stimuli unaffected by the context in which they appear. Interdependent self-construals facilitate context-bounded thinking (i.e., processing stimuli by paying attention to their relation to the given context). With semantic-free dependent variables, 4 experiments showed independence-primed participants to exhibit higher degrees of context independence than did interdependence-primed participants. The results are discussed with reference to their potential explanations for cross-cultural differences.

  16. Chronic joint pain in the lower body is associated with gait differences independent from radiographic osteoarthritis.

    PubMed

    de Kruijf, Marjolein; Verlinden, Vincentius J A; Huygen, Frank J P M; Hofman, Albert; van der Geest, Jos N; Uitterlinden, Andre G; Bierma-Zeinstra, Sita M A; Ikram, M Arfan; van Meurs, Joyce B J

    2015-09-01

    Gait is an important indicator of health. Chronic lower body pain may impair gait and lead to morbidity and mortality. We investigated the associations between lower body pain and gait in community-dwelling individuals, independent from osteoarthritis (OA). This population based cohort study included 2304 Rotterdam Study participants who underwent electronic walkway gait assessment. Thirty different variables resulting from gait assessment were summarized into seven gait domains using principle components analysis: i.e. Rhythm, Variability, Phases, Pace, Tandem, Turning, and Base of Support. Chronic lower body pain was assessed using pain drawings. OA was defined as a Kellgren & Lawrence score of 2 or higher on radiographs of the hip and/or knee. Linear regression analysis was used to study associations. Participants with chronic pain in the leg and hip, had lower Rhythm, Phases, and Pace, independent from OA. Additionally, we found unilateral pain to associate with larger gait asymmetry. No associations were found between chronic pain and the other gait domains, including gait variability. However, within individuals with hip pain, gait variability was higher in individuals with radiographic OA compared to those without OA. This is the first population based study showing chronic lower body pain associates with gait differences independent from OA. Participants with pain were found to walk with slower and smaller steps, longer double support and more asymmetry. Proper care and treatment of chronic pain could be a way of reducing gait problems and thereby fall risk and associated mortality. In addition, gait assessment may help identifying individuals with OA from those having pain due to other causes.

  17. Frictionless continuously variable transmission

    SciTech Connect

    Korban, J.F.; Korban, N.F.

    1989-07-25

    This patent describes an infinitely variable speed transmission. It comprises: an input shaft; a drive plate having a plurality of radial slots therein, the drive plate fixed to the input shaft; an output shaft parallel to the input shaft; a bevel gear fixed to the output shaft; a plurality if independently rotatable sprocketed pinions freely rotatable about and meshing with the bevel gear. The pinions also engaging the drive plate by projections from the pinions slidably mounted in the radial slots in the drive plate; and clutching means for selectively locking and unlocking the pinions in sequence to effect driving of the bevel gear.

  18. Prognostic significance of heart rate variability in centenarians.

    PubMed

    Shimizu, Kenichiro; Arai, Yasumichi; Hirose, Nobuyoshi; Yonemoto, Takayuki; Wakida, Yasushi

    2002-01-01

    We studied the significance for further survival of heart rate variability and other variables in the very elderly. In 1992, we assessed activities of daily living, cognitive function, and nutritional status in 27 centenarians with no disease, in addition to the power of the heart rate variability in the ultralow, very low, low (LF), and high frequency (HF) bands. In 1996, we assessed survival in these centenarians; 17 had died and 10 were still living. Logistic regression analysis using backward elimination detected three factors, dementia, LF/HF, and age, that independently influenced mortality. Mortality risk increased with greater age in 1992, more severe dementia, or lower LF/HF. Sympathetic nerve activity, represented as LF/HF, may be associated with prognosis for survival in centenarians.

  19. Variable stiffness torsion springs

    NASA Technical Reports Server (NTRS)

    Alhorn, Dean C. (Inventor); Polites, Michael E. (Inventor)

    1994-01-01

    In a torsion spring the spring action is a result of the relationships between the torque applied in twisting the spring, the angle through which the torsion spring twists, and the modulus of elasticity of the spring material in shear. Torsion springs employed industrially have been strips, rods, or bars, generally termed shafts, capabable of being flexed by twisting their axes. They rely on the variations in shearing forces to furnish an internal restoring torque. In the torsion springs herein the restoring torque is external and therefore independent of the shearing modulus of elasticity of the torsion spring shaft. Also provided herein is a variable stiffness torsion spring. This torsion spring can be so adjusted as to have a given spring constant. Such variable stiffness torsion springs are extremely useful in gimballed payloads such as sensors, telescopes, and electronic devices on such platforms as a space shuttle or a space station.

  20. Variable stiffness torsion springs

    NASA Technical Reports Server (NTRS)

    Alhorn, Dean C. (Inventor); Polites, Michael E. (Inventor)

    1995-01-01

    In a torsion spring the spring action is a result of the relationships between the torque applied in twisting the spring, the angle through which the torsion spring twists, and the modulus of elasticity of the spring material in shear. Torsion springs employed industrially have been strips, rods, or bars, generally termed shafts, capabable of being flexed by twisting their axes. They rely on the variations in shearing forces to furnish an internal restoring torque. In the torsion springs herein the restoring torque is external and therefore independent of the shearing modulus of elasticity of the torsion spring shaft. Also provided herein is a variable stiffness torsion spring. This torsion spring can be so adjusted as to have a given spring constant. Such variable stiffness torsion springs are extremely useful in gimballed payloads such as sensors, telescopes, and electronic devices on such platforms as a space shuttle or a space station.

  1. TabVar: Tabulated Variables

    2015-12-15

    TabVar: A Python library for manipulating datasets in the form of tabulated variables. Tables in tabvar contain many columns representing independent variables, but exactly one distinguished column for the dependent variable. Having a single distinguished column allows a natural lifting of arithmetic operators to tables, much (and in fact fully generalizing) multidimensional array arithmetic. The convenient syntax of whole-table arithmetic, along with the usual operations of filtering and aggregation, and all in the setting ofmore » python's interactive REPL allows for rapid exploration of datasets.« less

  2. TabVar: Tabulated Variables

    SciTech Connect

    Bachan, John

    2015-12-15

    TabVar: A Python library for manipulating datasets in the form of tabulated variables. Tables in tabvar contain many columns representing independent variables, but exactly one distinguished column for the dependent variable. Having a single distinguished column allows a natural lifting of arithmetic operators to tables, much (and in fact fully generalizing) multidimensional array arithmetic. The convenient syntax of whole-table arithmetic, along with the usual operations of filtering and aggregation, and all in the setting of python's interactive REPL allows for rapid exploration of datasets.

  3. Variable Lifting Index (VLI)

    PubMed Central

    Waters, Thomas; Occhipinti, Enrico; Colombini, Daniela; Alvarez-Casado, Enrique; Fox, Robert

    2015-01-01

    Objective: We seek to develop a new approach for analyzing the physical demands of highly variable lifting tasks through an adaptation of the Revised NIOSH (National Institute for Occupational Safety and Health) Lifting Equation (RNLE) into a Variable Lifting Index (VLI). Background: There are many jobs that contain individual lifts that vary from lift to lift due to the task requirements. The NIOSH Lifting Equation is not suitable in its present form to analyze variable lifting tasks. Method: In extending the prior work on the VLI, two procedures are presented to allow users to analyze variable lifting tasks. One approach involves the sampling of lifting tasks performed by a worker over a shift and the calculation of the Frequency Independent Lift Index (FILI) for each sampled lift and the aggregation of the FILI values into six categories. The Composite Lift Index (CLI) equation is used with lifting index (LI) category frequency data to calculate the VLI. The second approach employs a detailed systematic collection of lifting task data from production and/or organizational sources. The data are organized into simplified task parameter categories and further aggregated into six FILI categories, which also use the CLI equation to calculate the VLI. Results: The two procedures will allow practitioners to systematically employ the VLI method to a variety of work situations where highly variable lifting tasks are performed. Conclusions: The scientific basis for the VLI procedure is similar to that for the CLI originally presented by NIOSH; however, the VLI method remains to be validated. Application: The VLI method allows an analyst to assess highly variable manual lifting jobs in which the task characteristics vary from lift to lift during a shift. PMID:26646300

  4. Variable temperature, variable-gap Otto prism coupler for use in a vacuum environment

    NASA Astrophysics Data System (ADS)

    Cairns, G. F.; O'Prey, S. M.; Dawson, P.

    2000-11-01

    The field of surface polariton physics really took off with the prism coupling techniques developed by Kretschmann and Raether, and by Otto. This article reports on the construction and operation of a rotatable, in vacuo, variable temperature, Otto coupler with a coupling gap that can be varied by remote control. The specific design attributes of the system offer additional advantages to those of standard Otto systems of (i) temperature variation (ambient to 85 K), and (ii) the use of a valuable, additional reference point, namely the gap-independent reflectance at the Brewster angle at any given, fixed temperature. The instrument is placed firmly in a historical context of developments in the field. The efficacy of the coupler is demonstrated by sample attenuated total reflectance results on films of platinum, niobium, and yttrium barium copper oxide and on aluminum/gallium arsenide (Al/GaAs) Schottky diode structures.

  5. Variability of Neptune

    NASA Astrophysics Data System (ADS)

    Cruikshank, D. P.

    1985-10-01

    Earth based observers of Neptune found that the planet varies in brightness at various wavelengths in ways that suggest that changes occur in the planet's atmosphere on several different time-scales. Global inhomogeneities in high altitude haze distribution that are stable for several days permit measurements of the planet's rotation period (about 18 hours), but this stability sometimes breaks down, obscuring the diurnal lightcurve. In addition, there is an apparent long term variability of the brightness of Neptune in anticorrelation with the cycle of solar activity. This slow variability of low amplitude may be punctuated by outbursts of high altitude condensation of particles in the atmosphere, whose decay time is several months.

  6. Septic tank additive impacts on microbial populations.

    PubMed

    Pradhan, S; Hoover, M T; Clark, G H; Gumpertz, M; Wollum, A G; Cobb, C; Strock, J

    2008-01-01

    Environmental health specialists, other onsite wastewater professionals, scientists, and homeowners have questioned the effectiveness of septic tank additives. This paper describes an independent, third-party, field scale, research study of the effects of three liquid bacterial septic tank additives and a control (no additive) on septic tank microbial populations. Microbial populations were measured quarterly in a field study for 12 months in 48 full-size, functioning septic tanks. Bacterial populations in the 48 septic tanks were statistically analyzed with a mixed linear model. Additive effects were assessed for three septic tank maintenance levels (low, intermediate, and high). Dunnett's t-test for tank bacteria (alpha = .05) indicated that none of the treatments were significantly different, overall, from the control at the statistical level tested. In addition, the additives had no significant effects on septic tank bacterial populations at any of the septic tank maintenance levels. Additional controlled, field-based research iswarranted, however, to address additional additives and experimental conditions.

  7. Robust language-independent OCR system

    NASA Astrophysics Data System (ADS)

    Lu, Zhidong A.; Bazzi, Issam; Kornai, Andras; Makhoul, John; Natarajan, Premkumar S.; Schwartz, Richard

    1999-01-01

    We present a language-independent optical character recognition system that is capable, in principle, of recognizing printed text from most of the world's languages. For each new language or script the system requires sample training data along with ground truth at the text-line level; there is no need to specify the location of either the lines or the words and characters. The system uses hidden Markov modeling technology to model each character. In addition to language independence, the technology enhances performance for degraded data, such as fax, by using unsupervised adaptation techniques. Thus far, we have demonstrated the language-independence of this approach for Arabic, English, and Chinese. Recognition results are presented in this paper, including results on faxed data.

  8. [Food additives and healthiness].

    PubMed

    Heinonen, Marina

    2014-01-01

    Additives are used for improving food structure or preventing its spoilage, for example. Many substances used as additives are also naturally present in food. The safety of additives is evaluated according to commonly agreed principles. If high concentrations of an additive cause adverse health effects for humans, a limit of acceptable daily intake (ADI) is set for it. An additive is a risk only when ADI is exceeded. The healthiness of food is measured on the basis of nutrient density and scientifically proven effects.

  9. Variable effort fishing models in random environments.

    PubMed

    Braumann, C A

    1999-03-01

    We study the growth of populations in a random environment subjected to variable effort fishing policies. The models used are stochastic differential equations and the environmental fluctuations may either affect an intrinsic growth parameter or be of the additive noise type. Density-dependent natural growth and fishing policies are of very general form so that our results will be model independent. We obtain conditions on the fishing policies for non-extinction and for non-fixation at the carrying capacity that are very similar to the conditions obtained for the corresponding deterministic model. We also obtain conditions for the existence of stationary distributions (as well as expressions for such distributions) very similar to conditions for the existence of an equilibrium in the corresponding deterministic model. The results obtained provide minimal requirements for the choice of a wise density-dependent fishing policy.

  10. Variable spectra of active galaxies

    NASA Technical Reports Server (NTRS)

    Halpern, Jules P.

    1988-01-01

    The analysis of EXOSAT spectra of active galaxies are presented. The objects examined for X-ray spectral variability were MR 2251-178 and 3C 120. The results of these investigations are described, as well as additional results on X-ray spectral variability related to EXOSAT observations of active galaxies. Additionally, the dipping X-ray source 4U1624-49 was also investigated.

  11. An Efficient Variable-Length Data-Compression Scheme

    NASA Technical Reports Server (NTRS)

    Cheung, Kar-Ming; Kiely, Aaron B.

    1996-01-01

    Adaptive variable-length coding scheme for compression of stream of independent and identically distributed source data involves either Huffman code or alternating run-length Huffman (ARH) code, depending on characteristics of data. Enables efficient compression of output of lossless or lossy precompression process, with speed and simplicity greater than those of older coding schemes developed for same purpose. In addition, scheme suitable for parallel implementation on hardware with modular structure, provides for rapid adaptation to changing data source, compatible with block orientation to alleviate memory requirements, ensures efficiency over wide range of entropy, and easily combined with such other communication schemes as those for containment of errors and for packetization.

  12. The Independent Evolution Method Is Not a Viable Phylogenetic Comparative Method

    PubMed Central

    2015-01-01

    Phylogenetic comparative methods (PCMs) use data on species traits and phylogenetic relationships to shed light on evolutionary questions. Recently, Smaers and Vinicius suggested a new PCM, Independent Evolution (IE), which purportedly employs a novel model of evolution based on Felsenstein’s Adaptive Peak Model. The authors found that IE improves upon previous PCMs by producing more accurate estimates of ancestral states, as well as separate estimates of evolutionary rates for each branch of a phylogenetic tree. Here, we document substantial theoretical and computational issues with IE. When data are simulated under a simple Brownian motion model of evolution, IE produces severely biased estimates of ancestral states and changes along individual branches. We show that these branch-specific changes are essentially ancestor-descendant or “directional” contrasts, and draw parallels between IE and previous PCMs such as “minimum evolution”. Additionally, while comparisons of branch-specific changes between variables have been interpreted as reflecting the relative strength of selection on those traits, we demonstrate through simulations that regressing IE estimated branch-specific changes against one another gives a biased estimate of the scaling relationship between these variables, and provides no advantages or insights beyond established PCMs such as phylogenetically independent contrasts. In light of our findings, we discuss the results of previous papers that employed IE. We conclude that Independent Evolution is not a viable PCM, and should not be used in comparative analyses. PMID:26683838

  13. Assessing Early Intervention Outcomes: Beyond Program Variables.

    ERIC Educational Resources Information Center

    Marfo, Kofi; Dinero, Thomas E.

    1991-01-01

    This paper argues that efficacy of early intervention must be assessed in relation to both program and extra-program variables. A framework outlining five classes of independent variables and two classes of outcomes to be considered in efficacy research is presented, and regression and path analytic techniques are suggested as tools for addressing…

  14. Examining Variability in Superintendent Community Involvement

    ERIC Educational Resources Information Center

    Kowalski, Theodore J.; Young, I. Phillip; Petersen, George J.

    2013-01-01

    This study examined the extent to which four independent variables (age, gender, education level, and district type) accounted for variability in superintendent community involvement. Two covariates associated with levels of community involvement (disposition toward community involvement and district enrollment) were infused to assess the impact…

  15. Algebraic independence properties related to certain infinite products

    NASA Astrophysics Data System (ADS)

    Tanaka, Taka-aki

    2011-09-01

    In this paper we establish algebraic independence of the values of a certain infinite product as well as its all successive derivatives at algebraic points other than its zeroes, using the fact that the logarithmic derivative of an infinite product gives a partial fraction expansion. Such an infinite product is generated by a linear recurrence. The method used for proving the algebraic independence is based on the theory of Mahler functions of several variables.

  16. THE COLOR VARIABILITY OF QUASARS

    SciTech Connect

    Schmidt, Kasper B.; Rix, Hans-Walter; Knecht, Matthias; Hogg, David W.; Shields, Joseph C.; Maoz, Dan; Bovy, Jo

    2012-01-10

    We quantify quasar color variability using an unprecedented variability database-ugriz photometry of 9093 quasars from Sloan Digital Sky Survey (SDSS) Stripe 82, observed over 8 years at {approx}60 epochs each. We confirm previous reports that quasars become bluer when brightening. We find a redshift dependence of this blueing in a given set of bands (e.g., g and r), but show that it is the result of the flux contribution from less-variable or delayed emission lines in the different SDSS bands at different redshifts. After correcting for this effect, quasar color variability is remarkably uniform, and independent not only of redshift, but also of quasar luminosity and black hole mass. The color variations of individual quasars, as they vary in brightness on year timescales, are much more pronounced than the ranges in color seen in samples of quasars across many orders of magnitude in luminosity. This indicates distinct physical mechanisms behind quasar variability and the observed range of quasar luminosities at a given black hole mass-quasar variations cannot be explained by changes in the mean accretion rate. We do find some dependence of the color variability on the characteristics of the flux variations themselves, with fast, low-amplitude, brightness variations producing more color variability. The observed behavior could arise if quasar variability results from flares or ephemeral hot spots in an accretion disk.

  17. Independent Learning Models: A Comparison.

    ERIC Educational Resources Information Center

    Wickett, R. E. Y.

    Five models of independent learning are suitable for use in adult education programs. The common factor is a facilitator who works in some way with the student in the learning process. They display different characteristics, including the extent of independence in relation to content and/or process. Nondirective tutorial instruction and learning…

  18. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Fletcher, James C. (Inventor); Pratt, J. Richard (Inventor); St.clair, Terry L. (Inventor); Stoakley, Diane M. (Inventor); Burks, Harold D. (Inventor)

    1992-01-01

    A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

  19. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Pratt, J. Richard (Inventor); St.clair, Terry L. (Inventor); Stoakley, Diane M. (Inventor); Burks, Harold D. (Inventor)

    1993-01-01

    A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of the additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

  20. Scale-Independent Measures and Pathologic Cardiac Dynamics

    NASA Astrophysics Data System (ADS)

    Amaral, Luís A.; Goldberger, Ary L.; Ivanov, Plamen Ch.; Stanley, H. Eugene

    1998-09-01

    We study several scale-independent measures of cardiac interbeat interval dynamics defined through the application of the wavelet transform. We test their performance in detecting heart disease using a database consisting of records of interbeat intervals for a group of healthy individuals and subjects with congestive heart failure. We find that scale-independent measures effectively distinguish healthy from pathologic behavior and propose a new two-variable scale-independent measure that could be clinically useful. We compare the performance of a recently proposed scale-dependent measure and find that the results depend on the database analyzed and on the analyzing wavelet.

  1. Additional Types of Neuropathy

    MedlinePlus

    ... A A Listen En Español Additional Types of Neuropathy Charcot's Joint Charcot's Joint, also called neuropathic arthropathy, ... can stop bone destruction and aid healing. Cranial Neuropathy Cranial neuropathy affects the 12 pairs of nerves ...

  2. Food Additives and Hyperkinesis

    ERIC Educational Resources Information Center

    Wender, Ester H.

    1977-01-01

    The hypothesis that food additives are causally associated with hyperkinesis and learning disabilities in children is reviewed, and available data are summarized. Available from: American Medical Association 535 North Dearborn Street Chicago, Illinois 60610. (JG)

  3. Smog control fuel additives

    SciTech Connect

    Lundby, W.

    1993-06-29

    A method is described of controlling, reducing or eliminating, ozone and related smog resulting from photochemical reactions between ozone and automotive or industrial gases comprising the addition of iodine or compounds of iodine to hydrocarbon-base fuels prior to or during combustion in an amount of about 1 part iodine per 240 to 10,000,000 parts fuel, by weight, to be accomplished by: (a) the addition of these inhibitors during or after the refining or manufacturing process of liquid fuels; (b) the production of these inhibitors for addition into fuel tanks, such as automotive or industrial tanks; or (c) the addition of these inhibitors into combustion chambers of equipment utilizing solid fuels for the purpose of reducing ozone.

  4. Length-independent structural similarities enrich the antibody CDR canonical class model

    PubMed Central

    Nowak, Jaroslaw; Baker, Terry; Georges, Guy; Kelm, Sebastian; Klostermann, Stefan; Shi, Jiye; Sridharan, Sudharsan; Deane, Charlotte M.

    2016-01-01

    ABSTRACT Complementarity-determining regions (CDRs) are antibody loops that make up the antigen binding site. Here, we show that all CDR types have structurally similar loops of different lengths. Based on these findings, we created length-independent canonical classes for the non-H3 CDRs. Our length variable structural clusters show strong sequence patterns suggesting either that they evolved from the same original structure or result from some form of convergence. We find that our length-independent method not only clusters a larger number of CDRs, but also predicts canonical class from sequence better than the standard length-dependent approach. To demonstrate the usefulness of our findings, we predicted cluster membership of CDR-L3 sequences from 3 next-generation sequencing datasets of the antibody repertoire (over 1,000,000 sequences). Using the length-independent clusters, we can structurally classify an additional 135,000 sequences, which represents a ∼20% improvement over the standard approach. This suggests that our length-independent canonical classes might be a highly prevalent feature of antibody space, and could substantially improve our ability to accurately predict the structure of novel CDRs identified by next-generation sequencing. PMID:26963563

  5. Progress in cultivation-independent phyllosphere microbiology.

    PubMed

    Müller, Thomas; Ruppel, Silke

    2014-01-01

    Most microorganisms of the phyllosphere are nonculturable in commonly used media and culture conditions, as are those in other natural environments. This review queries the reasons for their 'noncultivability' and assesses developments in phyllospere microbiology that have been achieved cultivation independently over the last 4 years. Analyses of total microbial communities have revealed a comprehensive microbial diversity. 16S rRNA gene amplicon sequencing and metagenomic sequencing were applied to investigate plant species, location and season as variables affecting the composition of these communities. In continuation to culture-based enzymatic and metabolic studies with individual isolates, metaproteogenomic approaches reveal a great potential to study the physiology of microbial communities in situ. Culture-independent microbiological technologies as well advances in plant genetics and biochemistry provide methodological preconditions for exploring the interactions between plants and their microbiome in the phyllosphere. Improving and combining cultivation and culture-independent techniques can contribute to a better understanding of the phyllosphere ecology. This is essential, for example, to avoid human-pathogenic bacteria in plant food.

  6. Progress in cultivation-independent phyllosphere microbiology

    PubMed Central

    Müller, Thomas; Ruppel, Silke

    2014-01-01

    Most microorganisms of the phyllosphere are nonculturable in commonly used media and culture conditions, as are those in other natural environments. This review queries the reasons for their ‘noncultivability’ and assesses developments in phyllospere microbiology that have been achieved cultivation independently over the last 4 years. Analyses of total microbial communities have revealed a comprehensive microbial diversity. 16S rRNA gene amplicon sequencing and metagenomic sequencing were applied to investigate plant species, location and season as variables affecting the composition of these communities. In continuation to culture-based enzymatic and metabolic studies with individual isolates, metaproteogenomic approaches reveal a great potential to study the physiology of microbial communities in situ. Culture-independent microbiological technologies as well advances in plant genetics and biochemistry provide methodological preconditions for exploring the interactions between plants and their microbiome in the phyllosphere. Improving and combining cultivation and culture-independent techniques can contribute to a better understanding of the phyllosphere ecology. This is essential, for example, to avoid human–pathogenic bacteria in plant food. PMID:24003903

  7. Variable-volume turbocharger

    SciTech Connect

    Nakazawa, N.; Matsura, Y.; Takemoto, T.; Kohketsu, S.

    1988-01-19

    A variable-volume turbocharger device is described comprising a turbine housing having at least first and second exhaust gas passages divided by a partition wall provided in the housing. The first exhaust gas passage has a large flow characteristic and the second exhaust gas passage has a small flow characteristic. A first valve means operable to open and shut the first exhaust gas passage, and a second valve means operative to open and shut the second exhaust gas passage independently from the first valve means, each of the valve means having a valve member which cooperates with a valve seat to open and shut the corresponding exhaust gas passage, the valve members being arranged so as to open toward the upstream side of the flowing direction of exhaust gas with respect to the valve seats.

  8. Approximately Independent Features of Languages

    NASA Astrophysics Data System (ADS)

    Holman, Eric W.

    To facilitate the testing of models for the evolution of languages, the present paper offers a set of linguistic features that are approximately independent of each other. To find these features, the adjusted Rand index (R‧) is used to estimate the degree of pairwise relationship among 130 linguistic features in a large published database. Many of the R‧ values prove to be near zero, as predicted for independent features, and a subset of 47 features is found with an average R‧ of -0.0001. These 47 features are recommended for use in statistical tests that require independent units of analysis.

  9. Sequence independent amplification of DNA

    DOEpatents

    Bohlander, Stefan K.

    1998-01-01

    The present invention is a rapid sequence-independent amplification procedure (SIA). Even minute amounts of DNA from various sources can be amplified independent of any sequence requirements of the DNA or any a priori knowledge of any sequence characteristics of the DNA to be amplified. This method allows, for example the sequence independent amplification of microdissected chromosomal material and the reliable construction of high quality fluorescent in situ hybridization (FISH) probes from YACs or from other sources. These probes can be used to localize YACs on metaphase chromosomes but also--with high efficiency--in interphase nuclei.

  10. Sequence independent amplification of DNA

    DOEpatents

    Bohlander, S.K.

    1998-03-24

    The present invention is a rapid sequence-independent amplification procedure (SIA). Even minute amounts of DNA from various sources can be amplified independent of any sequence requirements of the DNA or any a priori knowledge of any sequence characteristics of the DNA to be amplified. This method allows, for example, the sequence independent amplification of microdissected chromosomal material and the reliable construction of high quality fluorescent in situ hybridization (FISH) probes from YACs or from other sources. These probes can be used to localize YACs on metaphase chromosomes but also--with high efficiency--in interphase nuclei. 25 figs.

  11. Independent component representations for face recognition

    NASA Astrophysics Data System (ADS)

    Stewart Bartlett, Marian; Lades, Martin H.; Sejnowski, Terrence J.

    1998-07-01

    In a task such as face recognition, much of the important information may be contained in the high-order relationships among the image pixels. A number of face recognition algorithms employ principal component analysis (PCA), which is based on the second-order statistics of the image set, and does not address high-order statistical dependencies such as the relationships among three or more pixels. Independent component analysis (ICA) is a generalization of PCA which separates the high-order moments of the input in addition to the second-order moments. ICA was performed on a set of face images by an unsupervised learning algorithm derived from the principle of optimal information transfer through sigmoidal neurons. The algorithm maximizes the mutual information between the input and the output, which produces statistically independent outputs under certain conditions. ICA was performed on the face images under two different architectures. The first architecture provided a statistically independent basis set for the face images that can be viewed as a set of independent facial features. The second architecture provided a factorial code, in which the probability of any combination of features can be obtained from the product of their individual probabilities. Both ICA representations were superior to representations based on principal components analysis for recognizing faces across sessions and changes in expression.

  12. Variability in surface ECG morphology: signal or noise?

    NASA Technical Reports Server (NTRS)

    Smith, J. M.; Rosenbaum, D. S.; Cohen, R. J.

    1988-01-01

    Using data collected from canine models of acute myocardial ischemia, we investigated two issues of major relevance to electrocardiographic signal averaging: ECG epoch alignment, and the spectral characteristics of the beat-to-beat variability in ECG morphology. With initial digitization rates of 1 kHz, an iterative a posteriori matched filtering alignment scheme, and linear interpolation, we demonstrated that there is sufficient information in the body surface ECG to merit alignment to a precision of 0.1 msecs. Applying this technique to align QRS complexes and atrial pacing artifacts independently, we demonstrated that the conduction delay from atrial stimulus to ventricular activation may be so variable as to preclude using atrial pacing as an alignment mechanism, and that this variability in conduction time be modulated at the frequency of respiration and at a much lower frequency (0.02-0.03Hz). Using a multidimensional spectral technique, we investigated the beat-to-beat variability in ECG morphology, demonstrating that the frequency spectrum of ECG morphological variation reveals a readily discernable modulation at the frequency of respiration. In addition, this technique detects a subtle beat-to-beat alternation in surface ECG morphology which accompanies transient coronary artery occlusion. We conclude that physiologically important information may be stored in the variability in the surface electrocardiogram, and that this information is lost by conventional averaging techniques.

  13. Additive Manufacturing Infrared Inspection

    NASA Technical Reports Server (NTRS)

    Gaddy, Darrell

    2014-01-01

    Additive manufacturing is a rapid prototyping technology that allows parts to be built in a series of thin layers from plastic, ceramics, and metallics. Metallic additive manufacturing is an emerging form of rapid prototyping that allows complex structures to be built using various metallic powders. Significant time and cost savings have also been observed using the metallic additive manufacturing compared with traditional techniques. Development of the metallic additive manufacturing technology has advanced significantly over the last decade, although many of the techniques to inspect parts made from these processes have not advanced significantly or have limitations. Several external geometry inspection techniques exist such as Coordinate Measurement Machines (CMM), Laser Scanners, Structured Light Scanning Systems, or even traditional calipers and gages. All of the aforementioned techniques are limited to external geometry and contours or must use a contact probe to inspect limited internal dimensions. This presentation will document the development of a process for real-time dimensional inspection technique and digital quality record of the additive manufacturing process using Infrared camera imaging and processing techniques.

  14. Some effects of procedural variables on operant choice behavior.

    PubMed

    Moore, Jay

    2010-05-01

    Procedural variables are concerned with the way subjects contact stimulus, response, and reinforcer variables and relations in an experiment. Procedural variables may therefore be understood as tools that allow researchers and theorists to explore the generality of their conceptions of independent variables, behavioral processes, and quantitative laws of behavior. The present article reviews data from several studies showing how procedural variables can influence the outcome of operant choice experiments, even when nominal independent variables remain constant. An important theoretical issue raised by these data is whether researchers have most usefully identified the independent variables that they incorporate into their quantitative models. Particular attention is paid to how procedural variables can influence the measure of reinforcement frequency over time that best correlates with the distribution of choice responding over time.

  15. Independent Schools: Landscape and Learnings.

    ERIC Educational Resources Information Center

    Oates, William A.

    1981-01-01

    Examines American independent schools (parochial, southern segregated, and private institutions) in terms of their funding, expenditures, changing enrollment patterns, teacher-student ratios, and societal functions. Journal available from Daedalus Subscription Department, 1172 Commonwealth Ave., Boston, MA 02132. (AM)

  16. Technology for Independent Living: Sourcebook.

    ERIC Educational Resources Information Center

    Enders, Alexandra, Ed.

    This sourcebook provides information for the practical implementation of independent living technology in the everyday rehabilitation process. "Information Services and Resources" lists databases, clearinghouses, networks, research and development programs, toll-free telephone numbers, consumer protection caveats, selected publications, and…

  17. Phenylethynyl Containing Reactive Additives

    NASA Technical Reports Server (NTRS)

    Connell, John W. (Inventor); Smith, Joseph G., Jr. (Inventor); Hergenrother, Paul M. (Inventor)

    2002-01-01

    Phenylethynyl containing reactive additives were prepared from aromatic diamine, containing phenylethvnvl groups and various ratios of phthalic anhydride and 4-phenylethynviphthalic anhydride in glacial acetic acid to form the imide in one step or in N-methyl-2-pvrrolidinone to form the amide acid intermediate. The reactive additives were mixed in various amounts (10% to 90%) with oligomers containing either terminal or pendent phenylethynyl groups (or both) to reduce the melt viscosity and thereby enhance processability. Upon thermal cure, the additives react and become chemically incorporated into the matrix and effect an increase in crosslink density relative to that of the host resin. This resultant increase in crosslink density has advantageous consequences on the cured resin properties such as higher glass transition temperature and higher modulus as compared to that of the host resin.

  18. Regression with Empirical Variable Selection: Description of a New Method and Application to Ecological Datasets

    PubMed Central

    Goodenough, Anne E.; Hart, Adam G.; Stafford, Richard

    2012-01-01

    Despite recent papers on problems associated with full-model and stepwise regression, their use is still common throughout ecological and environmental disciplines. Alternative approaches, including generating multiple models and comparing them post-hoc using techniques such as Akaike's Information Criterion (AIC), are becoming more popular. However, these are problematic when there are numerous independent variables and interpretation is often difficult when competing models contain many different variables and combinations of variables. Here, we detail a new approach, REVS (Regression with Empirical Variable Selection), which uses all-subsets regression to quantify empirical support for every independent variable. A series of models is created; the first containing the variable with most empirical support, the second containing the first variable and the next most-supported, and so on. The comparatively small number of resultant models (n = the number of predictor variables) means that post-hoc comparison is comparatively quick and easy. When tested on a real dataset – habitat and offspring quality in the great tit (Parus major) – the optimal REVS model explained more variance (higher R2), was more parsimonious (lower AIC), and had greater significance (lower P values), than full, stepwise or all-subsets models; it also had higher predictive accuracy based on split-sample validation. Testing REVS on ten further datasets suggested that this is typical, with R2 values being higher than full or stepwise models (mean improvement = 31% and 7%, respectively). Results are ecologically intuitive as even when there are several competing models, they share a set of “core” variables and differ only in presence/absence of one or two additional variables. We conclude that REVS is useful for analysing complex datasets, including those in ecology and environmental disciplines. PMID:22479605

  19. Variables related to romanticism and self-esteem in pregnant teenagers.

    PubMed

    Medora, N P; Goldstein, A; von der Hellen, C

    1993-01-01

    In this study, the Dean Romanticism Scale and the Bachman Self-esteem Scale were administered to 121 teenagers between the ages of 12 and 19 in Southern California to investigate their degree of romanticism and self-esteem. The study also explored whether there was any relationship between the dependent variables of romanticism and self-esteem and ten independent variables--age, race, place of residence during pregnancy, age when first sexual intercourse occurred, age when pregnancy occurred, incidence of sexual abuse, incidence of abortion, adoption considerations, whether the subject was currently sexually active, and whether the teenager planned to have a child with the father of the baby. The results indicated that two variables were significantly related to feelings of romanticism--adoption considerations and whether the adolescent planned to have a child with the baby's father. In addition, two variables were significantly related to self-esteem--the incidence of sexual abuse and the incidence of abortion. PMID:8456604

  20. Interactively variable isotropic resolution in computed tomography

    NASA Astrophysics Data System (ADS)

    Lapp, Robert M.; Kyriakou, Yiannis; Kachelrieß, Marc; Wilharm, Sylvia; Kalender, Willi A.

    2008-05-01

    An individual balancing between spatial resolution and image noise is necessary to fulfil the diagnostic requirements in medical CT imaging. In order to change influencing parameters, such as reconstruction kernel or effective slice thickness, additional raw-data-dependent image reconstructions have to be performed. Therefore, the noise versus resolution trade-off is time consuming and not interactively applicable. Furthermore, isotropic resolution, expressed by an equivalent point spread function (PSF) in every spatial direction, is important for the undistorted visualization and quantitative evaluation of small structures independent of the viewing plane. Theoretically, isotropic resolution can be obtained by matching the in-plane and through-plane resolution with the aforementioned parameters. Practically, however, the user is not assisted in doing so by current reconstruction systems and therefore isotropic resolution is not commonly achieved, in particular not at the desired resolution level. In this paper, an integrated approach is presented for equalizing the in-plane and through-plane spatial resolution by image filtering. The required filter kernels are calculated from previously measured PSFs in x/y- and z-direction. The concepts derived are combined with a variable resolution filtering technique. Both approaches are independent of CT raw data and operate only on reconstructed images which allows for their application in real time. Thereby, the aim of interactively variable, isotropic resolution is achieved. Results were evaluated quantitatively by measuring PSFs and image noise, and qualitatively by comparing the images to direct reconstructions regarded as the gold standard. Filtered images matched direct reconstructions with arbitrary reconstruction kernels with standard deviations in difference images of typically between 1 and 17 HU. Isotropic resolution was achieved within 5% of the selected resolution level. Processing times of 20-100 ms per frame

  1. Multifunctional fuel additives

    SciTech Connect

    Baillargeon, D.J.; Cardis, A.B.; Heck, D.B.

    1991-03-26

    This paper discusses a composition comprising a major amount of a liquid hydrocarbyl fuel and a minor low-temperature flow properties improving amount of an additive product of the reaction of a suitable diol and product of a benzophenone tetracarboxylic dianhydride and a long-chain hydrocarbyl aminoalcohol.

  2. Biobased lubricant additives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fully biobased lubricants are those formulated using all biobased ingredients, i.e. biobased base oils and biobased additives. Such formulations provide the maximum environmental, safety, and economic benefits expected from a biobased product. Currently, there are a number of biobased base oils that...

  3. Resume Writing in Russia and the Newly Independent States

    ERIC Educational Resources Information Center

    Bowen, Betsy; Sapp, David Alan; Sargsyan, Nelly

    2006-01-01

    This article examines the teaching of resume writing at one university in Russia and several institutions in the Newly Independent States (NIS). The authors explore challenges including variable cultural norms for written versus oral communication, severe financial and material hardship in the educational sector, cultural discomfort with the norms…

  4. A Boundary Mixture Approach to Violations of Conditional Independence

    ERIC Educational Resources Information Center

    Braeken, Johan

    2011-01-01

    Conditional independence is a fundamental principle in latent variable modeling and item response theory. Violations of this principle, commonly known as local item dependencies, are put in a test information perspective, and sharp bounds on these violations are defined. A modeling approach is proposed that makes use of a mixture representation of…

  5. Independent determinants of early death in critically ill surgical patients.

    PubMed

    Müller, Mario H; Moubarak, Patricia; Wolf, Hilde; Küchenhoff, Helmut; Jauch, Karl-Walter; Hartl, Wolfgang H

    2008-07-01

    Abnormalities in cardiocirculatory, respiratory, or coagulatory parameters are frequent after major surgery, but so far, no study has investigated their predictive value for early intensive care unit (ICU) mortality. We aimed to describe and quantify the relation between these parameters that are routinely determined on ICU admission and early death after complex surgery. Individual patient data were available from a local ICU database. We performed a retrospective observational cohort study using prospectively collected data from March 1, 1993, through February 28, 2005. A cohort of 4,214 cases who were admitted to the ICU immediately after operation was analyzed. We studied age, sex, number of red blood cell units transfused on admission day, and admission values for heart rate, systolic blood pressure, hemoglobin concentration, partial thromboplastin time, prothrombin time, respiratory function (Pao2/Fio2 ratio), and body temperature for their association with 4-day mortality. Effects were adjusted for the underlying disease and for disease severity during the first 24 h after admission. We used generalized additive models to fit continuous variables individually before combining them into the final generalized model. We found an independent linear association between the number of transfused red blood cell units, partial thromboplastin time, and body temperature with acute outcome. A smoothed model described the independent interaction between admission blood pressure and early death. Only values of less than 80 mmHg were associated with an increased risk of 4-day mortality. According to these results, bleeding complications after ICU admission should be treated aggressively to prevent early death of the patient. However, normotensive conditions do not seem to be required to prevent early mortality. Whether rapid rewarming may improve outcome needs further rigorous study.

  6. Mixed additive models

    NASA Astrophysics Data System (ADS)

    Carvalho, Francisco; Covas, Ricardo

    2016-06-01

    We consider mixed models y =∑i =0 w Xiβi with V (y )=∑i =1 w θiMi Where Mi=XiXi⊤ , i = 1, . . ., w, and µ = X0β0. For these we will estimate the variance components θ1, . . ., θw, aswell estimable vectors through the decomposition of the initial model into sub-models y(h), h ∈ Γ, with V (y (h ))=γ (h )Ig (h )h ∈Γ . Moreover we will consider L extensions of these models, i.e., y˚=Ly+ɛ, where L=D (1n1, . . ., 1nw) and ɛ, independent of y, has null mean vector and variance covariance matrix θw+1Iw, where w =∑i =1 n wi .

  7. Vinyl capped addition polyimides

    NASA Technical Reports Server (NTRS)

    Vannucci, Raymond D. (Inventor); Malarik, Diane C. (Inventor); Delvigs, Peter (Inventor)

    1991-01-01

    Polyimide resins (PMR) are generally useful where high strength and temperature capabilities are required (at temperatures up to about 700 F). Polyimide resins are particularly useful in applications such as jet engine compressor components, for example, blades, vanes, air seals, air splitters, and engine casing parts. Aromatic vinyl capped addition polyimides are obtained by reacting a diamine, an ester of tetracarboxylic acid, and an aromatic vinyl compound. Low void materials with improved oxidative stability when exposed to 700 F air may be fabricated as fiber reinforced high molecular weight capped polyimide composites. The aromatic vinyl capped polyimides are provided with a more aromatic nature and are more thermally stable than highly aliphatic, norbornenyl-type end-capped polyimides employed in PMR resins. The substitution of aromatic vinyl end-caps for norbornenyl end-caps in addition polyimides results in polymers with improved oxidative stability.

  8. Tackifier for addition polyimides

    NASA Technical Reports Server (NTRS)

    Butler, J. M.; St.clair, T. L.

    1980-01-01

    A modification to the addition polyimide, LaRC-160, was prepared to improve tack and drape and increase prepeg out-time. The essentially solventless, high viscosity laminating resin is synthesized from low cost liquid monomers. The modified version takes advantage of a reactive, liquid plasticizer which is used in place of solvent and helps solve a major problem of maintaining good prepeg tack and drape, or the ability of the prepeg to adhere to adjacent plies and conform to a desired shape during the lay up process. This alternate solventless approach allows both longer life of the polymer prepeg and the processing of low void laminates. This approach appears to be applicable to all addition polyimide systems.

  9. Electrophilic addition of astatine

    SciTech Connect

    Norseev, Yu.V.; Vasaros, L.; Nhan, D.D.; Huan, N.K.

    1988-03-01

    It has been shown for the first time that astatine is capable of undergoing addition reactions to unsaturated hydrocarbons. A new compound of astatine, viz., ethylene astatohydrin, has been obtained, and its retention numbers of squalane, Apiezon, and tricresyl phosphate have been found. The influence of various factors on the formation of ethylene astatohydrin has been studied. It has been concluded on the basis of the results obtained that the univalent cations of astatine in an acidic medium is protonated hypoastatous acid.

  10. Functional Generalized Additive Models.

    PubMed

    McLean, Mathew W; Hooker, Giles; Staicu, Ana-Maria; Scheipl, Fabian; Ruppert, David

    2014-01-01

    We introduce the functional generalized additive model (FGAM), a novel regression model for association studies between a scalar response and a functional predictor. We model the link-transformed mean response as the integral with respect to t of F{X(t), t} where F(·,·) is an unknown regression function and X(t) is a functional covariate. Rather than having an additive model in a finite number of principal components as in Müller and Yao (2008), our model incorporates the functional predictor directly and thus our model can be viewed as the natural functional extension of generalized additive models. We estimate F(·,·) using tensor-product B-splines with roughness penalties. A pointwise quantile transformation of the functional predictor is also considered to ensure each tensor-product B-spline has observed data on its support. The methods are evaluated using simulated data and their predictive performance is compared with other competing scalar-on-function regression alternatives. We illustrate the usefulness of our approach through an application to brain tractography, where X(t) is a signal from diffusion tensor imaging at position, t, along a tract in the brain. In one example, the response is disease-status (case or control) and in a second example, it is the score on a cognitive test. R code for performing the simulations and fitting the FGAM can be found in supplemental materials available online.

  11. Benefits of Stimulus Exposure: Developmental Learning Independent of Task Performance

    PubMed Central

    Green, David B.; Ohlemacher, Jocelyn; Rosen, Merri J.

    2016-01-01

    Perceptual learning (training-induced performance improvement) can be elicited by task-irrelevant stimulus exposure in humans. In contrast, task-irrelevant stimulus exposure in animals typically disrupts perception in juveniles while causing little to no effect in adults. This may be due to the extent of exposure, which is brief in humans while chronic in animals. Here we assessed the effects of short bouts of passive stimulus exposure on learning during development in gerbils, compared with non-passive stimulus exposure (i.e., during testing). We used prepulse inhibition of the acoustic startle response, a method that can be applied at any age, to measure gap detection thresholds across four age groups, spanning development. First, we showed that both gap detection thresholds and gap detection learning across sessions displayed a long developmental trajectory, improving throughout the juvenile period. Additionally, we demonstrated larger within- and across-animal performance variability in younger animals. These results are generally consistent with results in humans, where there are extended developmental trajectories for both the perception of temporally-varying signals, and the effects of perceptual training, as well as increased variability and poorer performance consistency in children. We then chose an age (mid-juveniles) that displayed clear learning over sessions in order to assess effects of brief passive stimulus exposure on this learning. We compared learning in mid-juveniles exposed to either gap detection testing (gaps paired with startles) or equivalent gap exposure without testing (gaps alone) for three sessions. Learning was equivalent in both these groups and better than both naïve age-matched animals and controls receiving no gap exposure but only startle testing. Thus, short bouts of exposure to gaps independent of task performance is sufficient to induce learning at this age, and is as effective as gap detection testing. PMID:27378837

  12. Benefits of Stimulus Exposure: Developmental Learning Independent of Task Performance.

    PubMed

    Green, David B; Ohlemacher, Jocelyn; Rosen, Merri J

    2016-01-01

    Perceptual learning (training-induced performance improvement) can be elicited by task-irrelevant stimulus exposure in humans. In contrast, task-irrelevant stimulus exposure in animals typically disrupts perception in juveniles while causing little to no effect in adults. This may be due to the extent of exposure, which is brief in humans while chronic in animals. Here we assessed the effects of short bouts of passive stimulus exposure on learning during development in gerbils, compared with non-passive stimulus exposure (i.e., during testing). We used prepulse inhibition of the acoustic startle response, a method that can be applied at any age, to measure gap detection thresholds across four age groups, spanning development. First, we showed that both gap detection thresholds and gap detection learning across sessions displayed a long developmental trajectory, improving throughout the juvenile period. Additionally, we demonstrated larger within- and across-animal performance variability in younger animals. These results are generally consistent with results in humans, where there are extended developmental trajectories for both the perception of temporally-varying signals, and the effects of perceptual training, as well as increased variability and poorer performance consistency in children. We then chose an age (mid-juveniles) that displayed clear learning over sessions in order to assess effects of brief passive stimulus exposure on this learning. We compared learning in mid-juveniles exposed to either gap detection testing (gaps paired with startles) or equivalent gap exposure without testing (gaps alone) for three sessions. Learning was equivalent in both these groups and better than both naïve age-matched animals and controls receiving no gap exposure but only startle testing. Thus, short bouts of exposure to gaps independent of task performance is sufficient to induce learning at this age, and is as effective as gap detection testing.

  13. Benefits of Stimulus Exposure: Developmental Learning Independent of Task Performance.

    PubMed

    Green, David B; Ohlemacher, Jocelyn; Rosen, Merri J

    2016-01-01

    Perceptual learning (training-induced performance improvement) can be elicited by task-irrelevant stimulus exposure in humans. In contrast, task-irrelevant stimulus exposure in animals typically disrupts perception in juveniles while causing little to no effect in adults. This may be due to the extent of exposure, which is brief in humans while chronic in animals. Here we assessed the effects of short bouts of passive stimulus exposure on learning during development in gerbils, compared with non-passive stimulus exposure (i.e., during testing). We used prepulse inhibition of the acoustic startle response, a method that can be applied at any age, to measure gap detection thresholds across four age groups, spanning development. First, we showed that both gap detection thresholds and gap detection learning across sessions displayed a long developmental trajectory, improving throughout the juvenile period. Additionally, we demonstrated larger within- and across-animal performance variability in younger animals. These results are generally consistent with results in humans, where there are extended developmental trajectories for both the perception of temporally-varying signals, and the effects of perceptual training, as well as increased variability and poorer performance consistency in children. We then chose an age (mid-juveniles) that displayed clear learning over sessions in order to assess effects of brief passive stimulus exposure on this learning. We compared learning in mid-juveniles exposed to either gap detection testing (gaps paired with startles) or equivalent gap exposure without testing (gaps alone) for three sessions. Learning was equivalent in both these groups and better than both naïve age-matched animals and controls receiving no gap exposure but only startle testing. Thus, short bouts of exposure to gaps independent of task performance is sufficient to induce learning at this age, and is as effective as gap detection testing. PMID:27378837

  14. New opportunities seen for independents

    SciTech Connect

    Adams, G.A. )

    1990-10-22

    The collapse of gas and oil prices in the mid-1980s significantly reduced the number of independent exploration companies. At the same time, a fundamental shift occurred among major oil companies as they allocated their exploration budgets toward international operations and made major production purchases. Several large independents also embraced a philosophy of budget supplementation through joint venture partnership arrangements. This has created a unique and unusual window of opportunity for the smaller independents (defined for this article as exploration and production companies with a market value of less than $1 billion) to access the extensive and high quality domestic prospect inventories of the major and large independent oil and gas companies and to participate in the search for large reserve targets on attractive joint venture terms. Participation in these types of joint ventures, in conjunction with internally generated plays selected through the use of today's advanced technology (computer-enhanced, high-resolution seismic; horizontal drilling; etc.) and increasing process for oil and natural gas, presents the domestic exploration-oriented independent with an attractive money-making opportunity for the 1990s.

  15. Attitude Towards Physics and Additional Mathematics Achievement Towards Physics Achievement

    ERIC Educational Resources Information Center

    Veloo, Arsaythamby; Nor, Rahimah; Khalid, Rozalina

    2015-01-01

    The purpose of this research is to identify the difference in students' attitude towards Physics and Additional Mathematics achievement based on gender and relationship between attitudinal variables towards Physics and Additional Mathematics achievement with achievement in Physics. This research focused on six variables, which is attitude towards…

  16. Independent component analysis-based classification of Alzheimer's MRI data

    PubMed Central

    Yang, Wenlu; Lui, Ronald L.M.; Gao, Jia-Hong; Chan, Tony F.; Yau, Shing-Tung; Sperling, Reisa A.; Huang, Xudong

    2013-01-01

    There is an unmet medical need to identify neuroimaging biomarkers that is able to accurately diagnose and monitor Alzheimer's disease (AD) at very early stages and assess the response to AD-modifying therapies. To a certain extent, volumetric and functional magnetic resonance imaging (fMRI) studies can detect changes in structure, cerebral blood flow and blood oxygenation that are able to distinguish AD and mild cognitive impairment (MCI) subjects from normal controls. However, it has been challenging to use fully automated MRI analytic methods to identify potential AD neuroimaging biomarkers. We have thus proposed a method based on independent component analysis (ICA), for studying potential AD-related MR image features, coupled with the use of support vector machine (SVM) for classifying scans into categories of AD, MCI, and normal control (NC) subjects. The MRI data were selected from Open Access Series of Imaging Studies (OASIS) and the Alzheimer's Disease Neuroimaging Initiative (ADNI) databases. The experimental results showed that our ICA-based method can differentiate AD and MCI subjects from normal controls, although further methodological improvement in the analytic method and inclusion of additional variables may be required for optimal classification. PMID:21321398

  17. The influence of climate variables on dengue in Singapore.

    PubMed

    Pinto, Edna; Coelho, Micheline; Oliver, Leuda; Massad, Eduardo

    2011-12-01

    In this work we correlated dengue cases with climatic variables for the city of Singapore. This was done through a Poisson Regression Model (PRM) that considers dengue cases as the dependent variable and the climatic variables (rainfall, maximum and minimum temperature and relative humidity) as independent variables. We also used Principal Components Analysis (PCA) to choose the variables that influence in the increase of the number of dengue cases in Singapore, where PC₁ (Principal component 1) is represented by temperature and rainfall and PC₂ (Principal component 2) is represented by relative humidity. We calculated the probability of occurrence of new cases of dengue and the relative risk of occurrence of dengue cases influenced by climatic variable. The months from July to September showed the highest probabilities of the occurrence of new cases of the disease throughout the year. This was based on an analysis of time series of maximum and minimum temperature. An interesting result was that for every 2-10°C of variation of the maximum temperature, there was an average increase of 22.2-184.6% in the number of dengue cases. For the minimum temperature, we observed that for the same variation, there was an average increase of 26.1-230.3% in the number of the dengue cases from April to August. The precipitation and the relative humidity, after analysis of correlation, were discarded in the use of Poisson Regression Model because they did not present good correlation with the dengue cases. Additionally, the relative risk of the occurrence of the cases of the disease under the influence of the variation of temperature was from 1.2-2.8 for maximum temperature and increased from 1.3-3.3 for minimum temperature. Therefore, the variable temperature (maximum and minimum) was the best predictor for the increased number of dengue cases in Singapore.

  18. Photonic variable delay devices based on optical birefringence

    NASA Technical Reports Server (NTRS)

    Yao, X. Steve (Inventor)

    2005-01-01

    Optical variable delay devices for providing variable true time delay to multiple optical beams simultaneously. A ladder-structured variable delay device comprises multiple basic building blocks stacked on top of each other resembling a ladder. Each basic building block has two polarization beamsplitters and a polarization rotator array arranged to form a trihedron; Controlling an array element of the polarization rotator array causes a beam passing through the array element either going up to a basic building block above it or reflect back towards a block below it. The beams going higher on the ladder experience longer optical path delay. An index-switched optical variable delay device comprises of many birefringent crystal segments connected with one another, with a polarization rotator array sandwiched between any two adjacent crystal segments. An array element in the polarization rotator array controls the polarization state of a beam passing through the element, causing the beam experience different refractive indices or path delays in the following crystal segment. By independently control each element in each polarization rotator array, variable optical path delays of each beam can be achieved. Finally, an index-switched variable delay device and a ladder-structured variable device are cascaded to form a new device which combines the advantages of the two individual devices. This programmable optic device has the properties of high packing density, low loss, easy fabrication, and virtually infinite bandwidth. The device is inherently two dimensional and has a packing density exceeding 25 lines/cm2. The delay resolution of the device is on the order of a femtosecond (one micron in space) and the total delay exceeds 10 nanosecond. In addition, the delay is reversible so that the same delay device can be used for both antenna transmitting and receiving.

  19. Model Independent Bounds on Kinetic Mixing

    SciTech Connect

    Hook, Anson; Izaguirre, Eder; Wacker, Jay G.; /SLAC

    2011-08-22

    New Abelian vector bosons can kinetically mix with the hypercharge gauge boson of the Standard Model. This letter computes the model independent limits on vector bosons with masses from 1 GeV to 1 TeV. The limits arise from the numerous e{sup +}e{sup -} experiments that have been performed in this energy range and bound the kinetic mixing by {epsilon} {approx}< 0.03 for most of the mass range studied, regardless of any additional interactions that the new vector boson may have.

  20. Predicting Ecologically Important Vegetation Variables from Remotely Sensed Optical/Radar Data Using Neural Networks

    NASA Technical Reports Server (NTRS)

    Kimes, Daniel S.; Nelson, Ross F.

    1998-01-01

    A number of satellite sensor systems will collect large data sets of the Earth's surface during NASA's Earth Observing System (EOS) era. Efforts are being made to develop efficient algorithms that can incorporate a wide variety of spectral data and ancillary data in order to extract vegetation variables required for global and regional studies of ecosystem processes, biosphere-atmosphere interactions, and carbon dynamics. These variables are, for the most part, continuous (e.g. biomass, leaf area index, fraction of vegetation cover, vegetation height, vegetation age, spectral albedo, absorbed photosynthetic active radiation, photosynthetic efficiency, etc.) and estimates may be made using remotely sensed data (e.g. nadir and directional optical wavelengths, multifrequency radar backscatter) and any other readily available ancillary data (e.g., topography, sun angle, ground data, etc.). Using these types of data, neural networks can: 1) provide accurate initial models for extracting vegetation variables when an adequate amount of data is available; 2) provide a performance standard for evaluating existing physically-based models; 3) invert multivariate, physically based models; 4) in a variable selection process, identify those independent variables which best infer the vegetation variable(s) of interest; and 5) incorporate new data sources that would be difficult or impossible to use with conventional techniques. In addition, neural networks employ a more powerful and adaptive nonlinear equation form as compared to traditional linear, index transformations, and simple nonlinear analyses. These neural networks attributes are discussed in the context of the authors' investigations of extracting vegetation variables of ecological interest.

  1. Independent bilateral primary bronchial carcinomas

    PubMed Central

    Chaudhuri, M. Ray

    1971-01-01

    Independent bilateral primary bronchial carcinomas are not common. Since Beyreuther's description in 1924, 16 well-documented cases of independent primary bronchial carcinomas of different histology have been described. From 1965 to 1970, eight cases were seen at the London Chest Hospital. In order to make the diagnosis of a second primary bronchial carcinoma, each tumour should be malignant and neither should be a metastasis from the other. To meet this last criterion, the histopathological features of the two tumours must be different. Many cases have been described in the literature as double primary bronchial carcinomas where the second primary had the same histological features as the first. Images PMID:4327711

  2. The Independent Technical Analysis Process

    SciTech Connect

    Duberstein, Corey A.; Ham, Kenneth D.; Dauble, Dennis D.; Johnson, Gary E.

    2007-04-13

    The Bonneville Power Administration (BPA) contracted with the Pacific Northwest National Laboratory (PNNL) to provide technical analytical support for system-wide fish passage information (BPA Project No. 2006-010-00). The goal of this project was to produce rigorous technical analysis products using independent analysts and anonymous peer reviewers. In the past, regional parties have interacted with a single entity, the Fish Passage Center to access the data, analyses, and coordination related to fish passage. This project provided an independent technical source for non-routine fish passage analyses while allowing routine support functions to be performed by other well-qualified entities.

  3. Q2DSTD NMR deciphers epitope-mapping variability for peptide recognition of integrin αvβ6† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c5ob01237f Click here for additional data file.

    PubMed Central

    Sorge, Jessica L.; Wagstaff, Jane L.; Rowe, Michelle L.

    2015-01-01

    Integrin αvβ6 is a cell surface arginine-glycine-aspartic acid (RGD)-specific heterodimeric glycoprotein that is only expressed on epithelia during processes of tissue remodelling, including cancer. The specificity and molecular nature of interactions toward this integrin are poorly understood and new insights into such processes are important to cell biologists and pharmaceutical drug discovery. This study demonstrates the application of quantitative two-dimensional saturation transfer (Q2DSTD) NMR to obtain precise details of peptide interactions with integrin αvβ6 and their correlation to specificity for the integrin. This approach highlights subtle but significant differences in ligand contact by three related 21-mer peptides: FMDV2, an αvβ6 specific peptide and DBD1 and LAP2T1 peptides that bind many αv integrins in addition to αvβ6. FMDV2 and DBD1 differ only by the cyclisation of DBD1; a process that removes αvβ6 specificity. Q2DSTD NMR demonstrates these peptides experience significantly different interactions with the integrin; FMDV contacts primarily through four residues: 6Leu, 10Leu, 12Val and 13Leu, whereas DBD1 and LAP2T1 have more widespread contacts across their sequences. Q2DSTD NMR combined two-dimensional STD with quantitation by considering the relaxation of the ligand (CRL) to provide precise ligand contact information. This study also examines the role of CRL in the Q2DSTD process and how quantitation modifies STD data and unravels epitope-mapping variability to provide precise results that differentiate interactions at the atomic level for each peptide. PMID:26119198

  4. Validation of China-wide interpolated daily climate variables from 1960 to 2011

    NASA Astrophysics Data System (ADS)

    Yuan, Wenping; Xu, Bing; Chen, Zhuoqi; Xia, Jiangzhou; Xu, Wenfang; Chen, Yang; Wu, Xiaoxu; Fu, Yang

    2015-02-01

    Temporally and spatially continuous meteorological variables are increasingly in demand to support many different types of applications related to climate studies. Using measurements from 600 climate stations, a thin-plate spline method was applied to generate daily gridded climate datasets for mean air temperature, maximum temperature, minimum temperature, relative humidity, sunshine duration, wind speed, atmospheric pressure, and precipitation over China for the period 1961-2011. A comprehensive evaluation of interpolated climate was conducted at 150 independent validation sites. The results showed superior performance for most of the estimated variables. Except for wind speed, determination coefficients ( R 2) varied from 0.65 to 0.90, and interpolations showed high consistency with observations. Most of the estimated climate variables showed relatively consistent accuracy among all seasons according to the root mean square error, R 2, and relative predictive error. The interpolated data correctly predicted the occurrence of daily precipitation at validation sites with an accuracy of 83 %. Moreover, the interpolation data successfully explained the interannual variability trend for the eight meteorological variables at most validation sites. Consistent interannual variability trends were observed at 66-95 % of the sites for the eight meteorological variables. Accuracy in distinguishing extreme weather events differed substantially among the meteorological variables. The interpolated data identified extreme events for the three temperature variables, relative humidity, and sunshine duration with an accuracy ranging from 63 to 77 %. However, for wind speed, air pressure, and precipitation, the interpolation model correctly identified only 41, 48, and 58 % of extreme events, respectively. The validation indicates that the interpolations can be applied with high confidence for the three temperatures variables, as well as relative humidity and sunshine duration based

  5. African American Race is an Independent Risk Factor in Survival from Initially Diagnosed Localized Breast Cancer

    PubMed Central

    Wieder, Robert; Shafiq, Basit; Adam, Nabil

    2016-01-01

    BACKGROUND: African American race negatively impacts survival from localized breast cancer but co-variable factors confound the impact. METHODS: Data sets were analyzed from the Surveillance, Epidemiology and End Results (SEER) directories from 1973 to 2011 consisting of patients with designated diagnosis of breast adenocarcinoma, race as White or Caucasian, Black or African American, Asian, American Indian or Alaskan Native, Native Hawaiian or Pacific Islander, age, stage I, II or III, grade 1, 2 or 3, estrogen receptor or progesterone receptor positive or negative, marital status as single, married, separated, divorced or widowed and laterality as right or left. The Cox Proportional Hazards Regression model was used to determine hazard ratios for survival. Chi square test was applied to determine the interdependence of variables found significant in the multivariable Cox Proportional Hazards Regression analysis. Cells with stratified data of patients with identical characteristics except African American or Caucasian race were compared. RESULTS: Age, stage, grade, ER and PR status and marital status significantly co-varied with race and with each other. Stratifications by single co-variables demonstrated worse hazard ratios for survival for African Americans. Stratification by three and four co-variables demonstrated worse hazard ratios for survival for African Americans in most subgroupings with sufficient numbers of values. Differences in some subgroupings containing poor prognostic co-variables did not reach significance, suggesting that race effects may be partly overcome by additional poor prognostic indicators. CONCLUSIONS: African American race is a poor prognostic indicator for survival from breast cancer independent of 6 associated co-variables with prognostic significance.

  6. African American Race is an Independent Risk Factor in Survival from Initially Diagnosed Localized Breast Cancer

    PubMed Central

    Wieder, Robert; Shafiq, Basit; Adam, Nabil

    2016-01-01

    BACKGROUND: African American race negatively impacts survival from localized breast cancer but co-variable factors confound the impact. METHODS: Data sets were analyzed from the Surveillance, Epidemiology and End Results (SEER) directories from 1973 to 2011 consisting of patients with designated diagnosis of breast adenocarcinoma, race as White or Caucasian, Black or African American, Asian, American Indian or Alaskan Native, Native Hawaiian or Pacific Islander, age, stage I, II or III, grade 1, 2 or 3, estrogen receptor or progesterone receptor positive or negative, marital status as single, married, separated, divorced or widowed and laterality as right or left. The Cox Proportional Hazards Regression model was used to determine hazard ratios for survival. Chi square test was applied to determine the interdependence of variables found significant in the multivariable Cox Proportional Hazards Regression analysis. Cells with stratified data of patients with identical characteristics except African American or Caucasian race were compared. RESULTS: Age, stage, grade, ER and PR status and marital status significantly co-varied with race and with each other. Stratifications by single co-variables demonstrated worse hazard ratios for survival for African Americans. Stratification by three and four co-variables demonstrated worse hazard ratios for survival for African Americans in most subgroupings with sufficient numbers of values. Differences in some subgroupings containing poor prognostic co-variables did not reach significance, suggesting that race effects may be partly overcome by additional poor prognostic indicators. CONCLUSIONS: African American race is a poor prognostic indicator for survival from breast cancer independent of 6 associated co-variables with prognostic significance. PMID:27698895

  7. Concurrent performances: reinforcement interaction and response independence.

    PubMed

    CATANIA, A C

    1963-04-01

    When a pigeon's pecks on two keys were reinforced concurrently by two independent variable-interval (VI) schedules, one for each key, the response rate on either key was given by the equation: R(1)=Kr(1)/(r(1)+r(2))(5/6), where R is response rate, r is reinforcement rate, and the subscripts 1 and 2 indicate keys 1 and 2. When the constant, K, was determined for a given pigeon in one schedule sequence, the equation predicted that pigeon's response rates in a second schedule sequence. The equation derived from two characteristics of the performance: the total response rate on the two keys was proportional to the one-sixth power of the total reinforcement rate provided by the two VI schedules; and, the pigeon matched the relative response rate on a key to the relative reinforcement rate for that key. The equation states that response rate on one key depends in part on reinforcement rate for the other key, but implies that it does not depend on response rate on the other key. This independence of response rates on the two keys was demonstrated by presenting a stimulus to the pigeon whenever one key's schedule programmed reinforcement. This maintained the reinforcement rate for that key, but reduced the response rate almost to zero. The response rate on the other key, nevertheless, continued to vary with reinforcement rates according to the equation.

  8. Haptic Tracking Permits Bimanual Independence

    ERIC Educational Resources Information Center

    Rosenbaum, David A.; Dawson, Amanda A.; Challis, John H.

    2006-01-01

    This study shows that in a novel task--bimanual haptic tracking--neurologically normal human adults can move their 2 hands independently for extended periods of time with little or no training. Participants lightly touched buttons whose positions were moved either quasi-randomly in the horizontal plane by 1 or 2 human drivers (Experiment 1), in…

  9. 10 Questions about Independent Reading

    ERIC Educational Resources Information Center

    Truby, Dana

    2012-01-01

    Teachers know that establishing a robust independent reading program takes more than giving kids a little quiet time after lunch. But how do they set up a program that will maximize their students' gains? Teachers have to know their students' reading levels inside and out, help them find just-right books, and continue to guide them during…

  10. Dimension independence in exterior algebra.

    PubMed Central

    Hawrylycz, M

    1995-01-01

    The identities between homogeneous expressions in rank 1 vectors and rank n - 1 covectors in a Grassmann-Cayley algebra of rank n, in which one set occurs multilinearly, are shown to represent a set of dimension-independent identities. The theorem yields an infinite set of nontrivial geometric identities from a given identity. PMID:11607520

  11. Field Independence: Reviewing the Evidence

    ERIC Educational Resources Information Center

    Evans, Carol; Richardson, John T. E.; Waring, Michael

    2013-01-01

    Background: The construct of ?eld independence (FI) remains one of the most widely cited notions in research on cognitive style and on learning and instruction more generally. However, a great deal of confusion continues to exist around the de?nition of FI, its measurement, and the interpretation of research results, all of which have served to…

  12. Independent Study Project, Topic: Topology.

    ERIC Educational Resources Information Center

    Notre Dame High School, Easton, PA.

    Using this guide and the four popular books noted in it, a student, working independently, will learn about some of the classical ideas and problems of topology: the Meobius strip and Klein bottle, the four color problem, genus of a surface, networks, Euler's formula, and the Jordan Curve Theorem. The unit culminates in a project of the students'…

  13. Boston: Cradle of American Independence

    ERIC Educational Resources Information Center

    Community College Journal, 2004

    2004-01-01

    The 2005 American Association of Community Colleges Annual Convention will be held April 6-9 in Boston. While thoroughly modern, the iconic city's identity is firmly rooted in the past. As the cradle of American independence, Boston's long history is an integral part of the American fabric. Adams, Revere, Hancock are more than historical figures;…

  14. Employee and independent contractor relationships.

    PubMed

    Wren, K R; Wren, T L; Monti, E J; Turco, S J

    1999-05-01

    Most practitioners find themselves at a disadvantage in dealing with business issues and relationships. As health care continues to change, knowledge of contracts and business relationships will help CRNA practitioners navigate new as well as traditional practice settings. This article discusses the advantages and disadvantages of two business relationships: employee and independent contractor. PMID:10504911

  15. Performance Boosting Additive

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Mainstream Engineering Corporation was awarded Phase I and Phase II contracts from Goddard Space Flight Center's Small Business Innovation Research (SBIR) program in early 1990. With support from the SBIR program, Mainstream Engineering Corporation has developed a unique low cost additive, QwikBoost (TM), that increases the performance of air conditioners, heat pumps, refrigerators, and freezers. Because of the energy and environmental benefits of QwikBoost, Mainstream received the Tibbetts Award at a White House Ceremony on October 16, 1997. QwikBoost was introduced at the 1998 International Air Conditioning, Heating, and Refrigeration Exposition. QwikBoost is packaged in a handy 3-ounce can (pressurized with R-134a) and will be available for automotive air conditioning systems in summer 1998.

  16. Sewage sludge additive

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J. J.; Mueller, W. A.; Ingham, J. D. (Inventor)

    1980-01-01

    The additive is for a raw sewage treatment process of the type where settling tanks are used for the purpose of permitting the suspended matter in the raw sewage to be settled as well as to permit adsorption of the dissolved contaminants in the water of the sewage. The sludge, which settles down to the bottom of the settling tank is extracted, pyrolyzed and activated to form activated carbon and ash which is mixed with the sewage prior to its introduction into the settling tank. The sludge does not provide all of the activated carbon and ash required for adequate treatment of the raw sewage. It is necessary to add carbon to the process and instead of expensive commercial carbon, coal is used to provide the carbon supplement.

  17. Perspectives on Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Bourell, David L.

    2016-07-01

    Additive manufacturing (AM) has skyrocketed in visibility commercially and in the public sector. This article describes the development of this field from early layered manufacturing approaches of photosculpture, topography, and material deposition. Certain precursors to modern AM processes are also briefly described. The growth of the field over the last 30 years is presented. Included is the standard delineation of AM technologies into seven broad categories. The economics of AM part generation is considered, and the impacts of the economics on application sectors are described. On the basis of current trends, the future outlook will include a convergence of AM fabricators, mass-produced AM fabricators, enabling of topology optimization designs, and specialization in the AM legal arena. Long-term developments with huge impact are organ printing and volume-based printing.

  18. Sarks as additional fermions

    NASA Astrophysics Data System (ADS)

    Agrawal, Jyoti; Frampton, Paul H.; Jack Ng, Y.; Nishino, Hitoshi; Yasuda, Osamu

    1991-03-01

    An extension of the standard model is proposed. The gauge group is SU(2) X ⊗ SU(3) C ⊗ SU(2) S ⊗ U(1) Q, where all gauge symmetries are unbroken. The colour and electric charge are combined with SU(2) S which becomes strongly coupled at approximately 500 GeV and binds preons to form fermionic and vector bound states. The usual quarks and leptons are singlets under SU(2) X but additional fermions, called sarks. transform under it and the electroweak group. The present model explains why no more than three light quark-lepton families can exist. Neutral sark baryons, called narks, are candidates for the cosmological dark matter having the characteristics designed for WIMPS. Further phenomenological implications of sarks are analyzed i including electron-positron annihilation. Z 0 decay, flavor-changing neutral currents. baryon-number non-conservation, sarkonium and the neutron electric dipole moment.

  19. Additive lattice kirigami

    PubMed Central

    Castle, Toen; Sussman, Daniel M.; Tanis, Michael; Kamien, Randall D.

    2016-01-01

    Kirigami uses bending, folding, cutting, and pasting to create complex three-dimensional (3D) structures from a flat sheet. In the case of lattice kirigami, this cutting and rejoining introduces defects into an underlying 2D lattice in the form of points of nonzero Gaussian curvature. A set of simple rules was previously used to generate a wide variety of stepped structures; we now pare back these rules to their minimum. This allows us to describe a set of techniques that unify a wide variety of cut-and-paste actions under the rubric of lattice kirigami, including adding new material and rejoining material across arbitrary cuts in the sheet. We also explore the use of more complex lattices and the different structures that consequently arise. Regardless of the choice of lattice, creating complex structures may require multiple overlapping kirigami cuts, where subsequent cuts are not performed on a locally flat lattice. Our additive kirigami method describes such cuts, providing a simple methodology and a set of techniques to build a huge variety of complex 3D shapes. PMID:27679822

  20. Additive lattice kirigami

    PubMed Central

    Castle, Toen; Sussman, Daniel M.; Tanis, Michael; Kamien, Randall D.

    2016-01-01

    Kirigami uses bending, folding, cutting, and pasting to create complex three-dimensional (3D) structures from a flat sheet. In the case of lattice kirigami, this cutting and rejoining introduces defects into an underlying 2D lattice in the form of points of nonzero Gaussian curvature. A set of simple rules was previously used to generate a wide variety of stepped structures; we now pare back these rules to their minimum. This allows us to describe a set of techniques that unify a wide variety of cut-and-paste actions under the rubric of lattice kirigami, including adding new material and rejoining material across arbitrary cuts in the sheet. We also explore the use of more complex lattices and the different structures that consequently arise. Regardless of the choice of lattice, creating complex structures may require multiple overlapping kirigami cuts, where subsequent cuts are not performed on a locally flat lattice. Our additive kirigami method describes such cuts, providing a simple methodology and a set of techniques to build a huge variety of complex 3D shapes.

  1. Steps to Independent Living Series.

    ERIC Educational Resources Information Center

    Lobb, Nancy

    This set of six activity books and a teacher's guide is designed to help students from eighth grade to adulthood with special needs to learn independent living skills. The activity books have a reading level of 2.5 and address: (1) "How to Get Well When You're Sick or Hurt," including how to take a temperature, see a doctor, and use medicines…

  2. Additive Effects of Repetition and Predictability during Comprehension: Evidence from Event-Related Potentials

    PubMed Central

    Barrios, Shannon; Parker, Dan; Morini, Giovanna; Lau, Ellen

    2014-01-01

    Previous research has shown that neural responses to words during sentence comprehension are sensitive to both lexical repetition and a word’s predictability in context. While previous research has often contrasted the effects of these variables (e.g. by looking at cases in which word repetition violates sentence-level constraints), little is known about how they work in tandem. In the current study we examine how recent exposure to a word and its predictability in context combine to impact lexical semantic processing. We devise a novel paradigm that combines reading comprehension with a recognition memory task, allowing for an orthogonal manipulation of a word’s predictability and its repetition status. Using event-related brain potentials (ERPs), we show that word repetition and predictability have qualitatively similar and additive effects on the N400 amplitude. We propose that prior exposure to a word and predictability impact lexical semantic processing in an additive and independent fashion. PMID:24905459

  3. A package for the automated classification of periodic variable stars

    NASA Astrophysics Data System (ADS)

    Kim, Dae-Won; Bailer-Jones, Coryn A. L.

    2016-03-01

    We present a machine learning package for the classification of periodic variable stars. Our package is intended to be general: it can classify any single band optical light curve comprising at least a few tens of observations covering durations from weeks to years with arbitrary time sampling. We use light curves of periodic variable stars taken from OGLE and EROS-2 to train the model. To make our classifier relatively survey-independent, it is trained on 16 features extracted from the light curves (e.g., period, skewness, Fourier amplitude ratio). The model classifies light curves into one of seven superclasses - δ Scuti, RR Lyrae, Cepheid, Type II Cepheid, eclipsing binary, long-period variable, non-variable - as well as subclasses of these, such as ab, c, d, and e types for RR Lyraes. When trained to give only superclasses, our model achieves 0.98 for both recall and precision as measured on an independent validation dataset (on a scale of 0 to 1). When trained to give subclasses, it achieves 0.81 for both recall and precision. The majority of misclassifications of the subclass model is caused by confusion within a superclass rather than between superclasses. To assess classification performance of the subclass model, we applied it to the MACHO, LINEAR, and ASAS periodic variables, which gave recall/precision of 0.92/0.98, 0.89/0.96, and 0.84/0.88, respectively. We also applied the subclass model to Hipparcos periodic variable stars of many other variability types that do not exist in our training set, in order to examine how much those types degrade the classification performance of our target classes. In addition, we investigate how the performance varies with the number of data points and duration of observations. We find that recall and precision do not vary significantly if there are more than 80 data points and the duration is more than a few weeks. The classifier software of the subclass model is available (in Python) from the GitHub repository (http

  4. 75 FR 5075 - New York Independent System Operator, Inc.; Notice of Filings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-01

    ... Energy Regulatory Commission New York Independent System Operator, Inc.; Notice of Filings January 22... Independent System Operator, Inc. (NYISO), filed in compliance with the Commission's January 15, 2010 Order in... proceeding and additional information directed by the Commission.\\2\\ \\1\\ New York Independent System...

  5. Application of independent component analysis in face images: a survey

    NASA Astrophysics Data System (ADS)

    Huang, Yuchi; Lu, Hanqing

    2003-09-01

    Face technologies which can be applied to access control and surveillance, are essential to intelligent vision-based human computer interaction. The research efforts in this field include face detecting, face recognition, face retrieval, etc. However, these tasks are challenging because of variability in view point, lighting, pose and expression of human faces. The ideal face representation should consider the variability so as to we can develop robust algorithms for our applications. Independent Component Analysis (ICA) as an unsupervised learning technique has been used to find such a representation and obtained good performances in some applications. In the first part of this paper, we depict the models of ICA and its extensions: Independent Subspace Analysis (ISA) and Topographic ICA (TICA).Then we summaraize the process in the applications of ICA and its extension in Face images. At last we propose a promising direction for future research.

  6. Predictive Inference Using Latent Variables with Covariates*

    PubMed Central

    Schofield, Lynne Steuerle; Junker, Brian; Taylor, Lowell J.; Black, Dan A.

    2014-01-01

    Plausible Values (PVs) are a standard multiple imputation tool for analysis of large education survey data that measures latent proficiency variables. When latent proficiency is the dependent variable, we reconsider the standard institutionally-generated PV methodology and find it applies with greater generality than shown previously. When latent proficiency is an independent variable, we show that the standard institutional PV methodology produces biased inference because the institutional conditioning model places restrictions on the form of the secondary analysts’ model. We offer an alternative approach that avoids these biases based on the mixed effects structural equations (MESE) model of Schofield (2008). PMID:25231627

  7. The Functional Independence of Mands and Tacts: Has It Been Demonstrated Empirically?

    ERIC Educational Resources Information Center

    Gamba, Jonas; Goyos, Celso; Petursdottir, Anna Ingeborg

    2015-01-01

    Recently, there has been a proliferation of research on the functional independence of two of Skinner's (1957) verbal operants, the mand, and the tact. This research has produced highly variable results. In this article, we provide a critical review of the literature on mand-tact independence, a literature that has implications for both theory and…

  8. Conflictual Independence, Adult Attachment Orientation, and Career Indecision among Asian American Students

    ERIC Educational Resources Information Center

    Keller, Chad J.; Brown, Chris

    2014-01-01

    Due to prior research suggesting that relational variables are related to the career development process, we sought to understand how maternal conflictual independence, paternal conflictual independence, attachment anxiety, and attachment avoidance influence the career decision status of Asian American undergraduate students (N = 113). The…

  9. Variable gravity research facility

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Eight fourth-year engineering design students formed two teams to study methods of varying the perceived gravity level in a variable gravity research facility. A tether system and an arm system were the chosen topics. Both teams have produced and built scale models of their design. In addition, a three-credit Special Topics Course (Aviation 370) was formed, as the project offers an excellent opportunity to build a multi-disciplinary program around the initial conceptualization process. Fifty students were registered in the Special Topics course. Each week during a three hour class, a guest lecturer covered one or more of the many areas associated with the concept of a variable-gravity facility. The students formed small groups organized on a multi-disciplinary basis (there were twelve separate disciplines represented by one or more students) where they discussed among themselves the various issues involved. These groups also met outside class for three or more hours each week. During class each group presented oral reports on their findings during a one-hour general question and answer period.

  10. Mass-independent isotope effects.

    PubMed

    Buchachenko, Anatoly L

    2013-02-28

    Three fundamental properties of atomic nuclei-mass, spin (and related magnetic moment), and volume-are the source of isotope effects. The mostly deserved and popular, with almost hundred-year history, is the mass-dependent isotope effect. The first mass-independent isotope effect which chemically discriminates isotopes by their nuclear spins and nuclear magnetic moments rather than by their masses was detected in 1976. It was named as the magnetic isotope effect because it is controlled by magnetic interaction, i.e., electron-nuclear hyperfine coupling in the paramagnetic species, the reaction intermediates. The effect follows from the universal physical property of chemical reactions to conserve angular momentum (spin) of electrons and nuclei. It is now detected for oxygen, silicon, sulfur, germanium, tin, mercury, magnesium, calcium, zinc, and uranium in a great variety of chemical and biochemical reactions including those of medical and ecological importance. Another mass-independent isotope effect was detected in 1983 as a deviation of isotopic distribution in reaction products from that which would be expected from the mass-dependent isotope effect. On the physical basis, it is in fact a mass-dependent effect, but it surprisingly results in isotope fractionation which is incompatible with that predicted by traditional mass-dependent effects. It is supposed to be a function of dynamic parameters of reaction and energy relaxation in excited states of products. The third, nuclear volume mass-independent isotope effect is detected in the high-resolution atomic and molecular spectra and in the extraction processes, but there are no unambiguous indications of its importance as an isotope fractionation factor in chemical reactions.

  11. Expanded HTA, Legitimacy and Independence

    PubMed Central

    Syrett, Keith

    2016-01-01

    This brief commentary seeks to develop the analysis of Daniels, Porteny and Urrutia of the implications of expansion of the scope of health technology assessment (HTA) beyond issues of safety, efficacy, and cost-effectiveness. Drawing in particular on experience in the United Kingdom, it suggests that such expansion can be understood not only as a response to the problem of insufficiency of evidence, but also to that of legitimacy. However, as expansion of HTA also renders it more visibly political in character, it is plausible that its legitimacy may be undermined, rather than enhanced by, independence from the policy process.

  12. Independent Component Analysis of Textures

    NASA Technical Reports Server (NTRS)

    Manduchi, Roberto; Portilla, Javier

    2000-01-01

    A common method for texture representation is to use the marginal probability densities over the outputs of a set of multi-orientation, multi-scale filters as a description of the texture. We propose a technique, based on Independent Components Analysis, for choosing the set of filters that yield the most informative marginals, meaning that the product over the marginals most closely approximates the joint probability density function of the filter outputs. The algorithm is implemented using a steerable filter space. Experiments involving both texture classification and synthesis show that compared to Principal Components Analysis, ICA provides superior performance for modeling of natural and synthetic textures.

  13. Indistinguishability of independent single photons

    NASA Astrophysics Data System (ADS)

    Sun, F. W.; Wong, C. W.

    2009-01-01

    The indistinguishability of independent single photons is presented by decomposing the single photon pulse into the mixed state of different transform-limited pulses. The entanglement between single photons and outer environment or other photons induces the distribution of the center frequencies of those transform-limited pulses and makes photons distinguishable. Only the single photons with the same transform-limited form are indistinguishable. In details, the indistinguishability of single photons from the solid-state quantum emitter and spontaneous parametric down-conversion is examined with two-photon Hong-Ou-Mandel interferometer. Moreover, experimental methods to enhance the indistinguishability are discussed, where the usage of spectral filter is highlighted.

  14. Transferability of regional permafrost disturbance susceptibility modelling using generalized linear and generalized additive models

    NASA Astrophysics Data System (ADS)

    Rudy, Ashley C. A.; Lamoureux, Scott F.; Treitz, Paul; van Ewijk, Karin Y.

    2016-07-01

    To effectively assess and mitigate risk of permafrost disturbance, disturbance-prone areas can be predicted through the application of susceptibility models. In this study we developed regional susceptibility models for permafrost disturbances using a field disturbance inventory to test the transferability of the model to a broader region in the Canadian High Arctic. Resulting maps of susceptibility were then used to explore the effect of terrain variables on the occurrence of disturbances within this region. To account for a large range of landscape characteristics, the model was calibrated using two locations: Sabine Peninsula, Melville Island, NU, and Fosheim Peninsula, Ellesmere Island, NU. Spatial patterns of disturbance were predicted with a generalized linear model (GLM) and generalized additive model (GAM), each calibrated using disturbed and randomized undisturbed locations from both locations and GIS-derived terrain predictor variables including slope, potential incoming solar radiation, wetness index, topographic position index, elevation, and distance to water. Each model was validated for the Sabine and Fosheim Peninsulas using independent data sets while the transferability of the model to an independent site was assessed at Cape Bounty, Melville Island, NU. The regional GLM and GAM validated well for both calibration sites (Sabine and Fosheim) with the area under the receiver operating curves (AUROC) > 0.79. Both models were applied directly to Cape Bounty without calibration and validated equally with AUROC's of 0.76; however, each model predicted disturbed and undisturbed samples differently. Additionally, the sensitivity of the transferred model was assessed using data sets with different sample sizes. Results indicated that models based on larger sample sizes transferred more consistently and captured the variability within the terrain attributes in the respective study areas. Terrain attributes associated with the initiation of disturbances were

  15. Identification of cognitive and non-cognitive predictive variables related to attrition in baccalaureate nursing education programs in Mississippi

    NASA Astrophysics Data System (ADS)

    Hayes, Catherine

    2005-07-01

    This study sought to identify a variable or variables predictive of attrition among baccalaureate nursing students. The study was quantitative in design and multivariate correlational statistics and discriminant statistical analysis were used to identify a model for prediction of attrition. The analysis then weighted variables according to their predictive value to determine the most parsimonious model with the greatest predictive value. Three public university nursing education programs in Mississippi offering a Bachelors Degree in Nursing were selected for the study. The population consisted of students accepted and enrolled in these three programs for the years 2001 and 2002 and graduating in the years 2003 and 2004 (N = 195). The categorical dependent variable was attrition (includes academic failure or withdrawal) from the program of nursing education. The ten independent variables selected for the study and considered to have possible predictive value were: Grade Point Average for Pre-requisite Course Work; ACT Composite Score, ACT Reading Subscore, and ACT Mathematics Subscore; Letter Grades in the Courses: Anatomy & Physiology and Lab I, Algebra I, English I (101), Chemistry & Lab I, and Microbiology & Lab I; and Number of Institutions Attended (Universities, Colleges, Junior Colleges or Community Colleges). Descriptive analysis was performed and the means of each of the ten independent variables was compared for students who attrited and those who were retained in the population. The discriminant statistical analysis performed created a matrix using the ten variable model that was able to correctly predicted attrition in the study's population in 77.6% of the cases. Variables were then combined and recombined to produce the most efficient and parsimonious model for prediction. A six variable model resulted which weighted each variable according to predictive value: GPA for Prerequisite Coursework, ACT Composite, English I, Chemistry & Lab I, Microbiology

  16. Speculations on a Definition of Independent Study.

    ERIC Educational Resources Information Center

    Moore, Michael G.

    The conceptual view of independent study that is developed in this paper is based on discussions of four key ideas: (1) independent study is concerned with both learning and teaching; (2) independent study is concerned with the capacity of learners to be self-directing; (3) independent study systems are both internal and external to educational…

  17. The theory of planned behaviour as predictor of exercise: the moderating influence of beliefs and personality variables.

    PubMed

    Bozionelos, G; Bennett, P

    1999-07-01

    In a test of the predictive utility of the theory of planned behaviour alone and in conjunction with a number of additional variables, 114 participants completed questionnaires measuring predictor variables and, three weeks later, reported exercise. The results of the present study provide partial support for the theory. Past behaviour was the most predictive variable. Subjective norm was not a significant predictor of intention to exercise. Attitude towards exercise was also not a predictor of exercise intention. Self-monitoring acted as a moderator of the attitude-intention relationship. Perceived behavioural control was not a significant predictor of exercise behaviour, while exercise intentions were only weak predictors. The results also suggested that perceived behavioural control and perceived barriers are not equivalent, and should be treated as separate variables that contribute independently to the predictive ability of the model. The implications of the findings are discussed. PMID:22021644

  18. ]Space Shuttle Independent Assessment Team

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The Shuttle program is one of the most complex engineering activities undertaken anywhere in the world at the present time. The Space Shuttle Independent Assessment Team (SIAT) was chartered in September 1999 by NASA to provide an independent review of the Space Shuttle sub-systems and maintenance practices. During the period from October through December 1999, the team led by Dr. McDonald and comprised of NASA, contractor, and DOD experts reviewed NASA practices, Space Shuffle anomalies, as well as civilian and military aerospace experience. In performing the review, much of a very positive nature was observed by the SIAT, not the least of which was the skill and dedication of the workforce. It is in the unfortunate nature of this type of review that the very positive elements are either not mentioned or dwelt upon. This very complex program has undergone a massive change in structure in the last few years with the transition to a slimmed down, contractor-run operation, the Shuttle Flight Operations Contract (SFOC). This has been accomplished with significant cost savings and without a major incident. This report has identified significant problems that must be addressed to maintain an effective program. These problems are described in each of the Issues, Findings or Observations summarized, and unless noted, appear to be systemic in nature and not confined to any one Shuttle sub-system or element. Specifics are given in the body of the report, along with recommendations to improve the present systems.

  19. Independent EEG Sources Are Dipolar

    PubMed Central

    Delorme, Arnaud; Palmer, Jason; Onton, Julie; Oostenveld, Robert; Makeig, Scott

    2012-01-01

    Independent component analysis (ICA) and blind source separation (BSS) methods are increasingly used to separate individual brain and non-brain source signals mixed by volume conduction in electroencephalographic (EEG) and other electrophysiological recordings. We compared results of decomposing thirteen 71-channel human scalp EEG datasets by 22 ICA and BSS algorithms, assessing the pairwise mutual information (PMI) in scalp channel pairs, the remaining PMI in component pairs, the overall mutual information reduction (MIR) effected by each decomposition, and decomposition ‘dipolarity’ defined as the number of component scalp maps matching the projection of a single equivalent dipole with less than a given residual variance. The least well-performing algorithm was principal component analysis (PCA); best performing were AMICA and other likelihood/mutual information based ICA methods. Though these and other commonly-used decomposition methods returned many similar components, across 18 ICA/BSS algorithms mean dipolarity varied linearly with both MIR and with PMI remaining between the resulting component time courses, a result compatible with an interpretation of many maximally independent EEG components as being volume-conducted projections of partially-synchronous local cortical field activity within single compact cortical domains. To encourage further method comparisons, the data and software used to prepare the results have been made available (http://sccn.ucsd.edu/wiki/BSSComparison). PMID:22355308

  20. Latent Variable Theory

    ERIC Educational Resources Information Center

    Borsboom, Denny

    2008-01-01

    This paper formulates a metatheoretical framework for latent variable modeling. It does so by spelling out the difference between observed and latent variables. This difference is argued to be purely epistemic in nature: We treat a variable as "observed" when the inference from data structure to variable structure can be made with certainty and as…

  1. 223. FREQUENTLY REPRODUCED VIEW OF GWMP SHOWING VARIABLE WIDTH MEDIANS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    223. FREQUENTLY REPRODUCED VIEW OF GWMP SHOWING VARIABLE WIDTH MEDIANS WITH INDEPENDENT ALIGNMENTS FROM KEY BRIDGE LOOKING NORTHWEST, 1953. - George Washington Memorial Parkway, Along Potomac River from McLean to Mount Vernon, VA, Mount Vernon, Fairfax County, VA

  2. On Gauge Independent Dynamical Chiral Symmetry Breaking

    SciTech Connect

    Bashir, A.; Raya, A.

    2006-09-25

    Schwinger-Dyson equations (SDEs) are an ideal framework to study nonperturbative phenomena such as dynamical chiral symmetry breaking (DCSB). Loss of gauge invariance is an obstacle to achieve fully reliable predictions from these equations. In addition to Ward-Green-Takahashi identity (WGTI), Landau-Khalatnikov-Fradkin transformations (LKFT) also play an important role in restoring the said invariance at the level of physical observables. On one hand, they impose useful constraints on the transverse part of the fermion-boson vertex and on the other, they govern the change in dynamically generated fermion propagator with a variation of gauge. We consider the latter in this article and study the gauge (in)dependence of chiral condensate in quantum electrodynamics in (2+1) space-time dimensions (QED3)

  3. Measurement-device-independent quantum cryptography

    SciTech Connect

    Xu, Feihu; Curty, Marcos; Qi, Bing; Lo, Hoi-Kwong

    2014-12-18

    In theory, quantum key distribution (QKD) provides information-theoretic security based on the laws of physics. Owing to the imperfections of real-life implementations, however, there is a big gap between the theory and practice of QKD, which has been recently exploited by several quantum hacking activities. To fill this gap, a novel approach, called measurement-device-independent QKD (mdiQKD), has been proposed. In addition, it can remove all side-channels from the measurement unit, arguably the most vulnerable part in QKD systems, thus offering a clear avenue toward secure QKD realisations. In this study, we review the latest developments in the framework of mdiQKD, together with its assumptions, strengths, and weaknesses.

  4. Measurement-device-independent quantum cryptography

    DOE PAGES

    Xu, Feihu; Curty, Marcos; Qi, Bing; Lo, Hoi-Kwong

    2014-12-18

    In theory, quantum key distribution (QKD) provides information-theoretic security based on the laws of physics. Owing to the imperfections of real-life implementations, however, there is a big gap between the theory and practice of QKD, which has been recently exploited by several quantum hacking activities. To fill this gap, a novel approach, called measurement-device-independent QKD (mdiQKD), has been proposed. In addition, it can remove all side-channels from the measurement unit, arguably the most vulnerable part in QKD systems, thus offering a clear avenue toward secure QKD realisations. In this study, we review the latest developments in the framework of mdiQKD,more » together with its assumptions, strengths, and weaknesses.« less

  5. Current Climate Variability & Change

    NASA Astrophysics Data System (ADS)

    Diem, J.; Criswell, B.; Elliott, W. C.

    2013-12-01

    Current Climate Variability & Change is the ninth among a suite of ten interconnected, sequential labs that address all 39 climate-literacy concepts in the U.S. Global Change Research Program's Climate Literacy: The Essential Principles of Climate Sciences. The labs are as follows: Solar Radiation & Seasons, Stratospheric Ozone, The Troposphere, The Carbon Cycle, Global Surface Temperature, Glacial-Interglacial Cycles, Temperature Changes over the Past Millennium, Climates & Ecosystems, Current Climate Variability & Change, and Future Climate Change. All are inquiry-based, on-line products designed in a way that enables students to construct their own knowledge of a topic. Questions representative of various levels of Webb's depth of knowledge are embedded in each lab. In addition to the embedded questions, each lab has three or four essential questions related to the driving questions for the lab suite. These essential questions are presented as statements at the beginning of the material to represent the lab objectives, and then are asked at the end as questions to function as a summative assessment. For example, the Current Climate Variability & Change is built around these essential questions: (1) What has happened to the global temperature at the Earth's surface, in the middle troposphere, and in the lower stratosphere over the past several decades?; (2) What is the most likely cause of the changes in global temperature over the past several decades and what evidence is there that this is the cause?; and (3) What have been some of the clearly defined effects of the change in global temperature on the atmosphere and other spheres of the Earth system? An introductory Prezi allows the instructor to assess students' prior knowledge in relation to these questions, while also providing 'hooks' to pique their interest related to the topic. The lab begins by presenting examples of and key differences between climate variability (e.g., Mt. Pinatubo eruption) and

  6. Variable conductance heat pipe technology

    NASA Technical Reports Server (NTRS)

    Marcus, B. D.; Edwards, D. K.; Anderson, W. T.

    1973-01-01

    Research and development programs in variable conductance heat pipe technology were conducted. The treatment has been comprehensive, involving theoretical and/or experimental studies in hydrostatics, hydrodynamics, heat transfer into and out of the pipe, fluid selection, and materials compatibility, in addition to the principal subject of variable conductance control techniques. Efforts were not limited to analytical work and laboratory experimentation, but extended to the development, fabrication and test of spacecraft hardware, culminating in the successful flight of the Ames Heat Pipe Experiment on the OAO-C spacecraft.

  7. Stochastically Perturbed Chains of Variable Memory

    NASA Astrophysics Data System (ADS)

    Garcia, Nancy L.; Moreira, Lucas

    2015-06-01

    In this paper, we study inference for chains of variable order under two distinct contamination regimes. Consider a chain of variable memory on a finite alphabet containing zero, at each instant of time an independent coin is flipped and if it turns head a contamination occurs. In the first regime a zero is read independently of the value of the chain. In the second regime, the value of another chain of variable memory is observed instead of the original one. Our results state that the difference between the transition probabilities of the original process and the corresponding ones of the contaminated process may be bounded above uniformly. Moreover, if the contamination probability is small enough, using a version of the Context algorithm we are able to recover the context tree of the original process through a contaminated sample.

  8. Independent mental health nurse prescribing.

    PubMed

    Jones, A; Harborne, G C

    2009-08-01

    Independent prescribing (IP) is a new form of prescriptive authority for mental health services. Very little is known about where IP is being implemented and factors to support or constrain its adoption. An opportunistic sample of 119 respondents made up of nurses, doctors, support workers, occupational therapists and social workers completed an online survey. The sample worked in adult, old age and substance misuse services. Hospital wards and community mental health teams were identified as the highest ranked areas for implementation. A total of 68% of the sample identified pharmacology as the area for further training. And 40% of the sample felt that IP had been introduced to make services more effective. This opportunistic sample supported IP as a means to offer greater patient choice and as a method to broaden the boundaries of nursing practice. Integral to this development is the link between the psychiatrist and IP nurse in terms of work allocation and supervision.

  9. Fluctuation theorems and entropy production with odd-parity variables

    NASA Astrophysics Data System (ADS)

    Park, Hyunggyu; Lee, Hyun Keun; Kwon, Chulan

    2013-03-01

    We show that the total entropy production in stochastic processes with odd-parity variables (under time reversal) is separated into three parts, only two of which satisfy the integral fluctuation theorems in general. One is the usual excess contribution, which can appear only transiently and is called non-adiabatic. Another one is attributed solely to the breakage of detailed balance. The last part not satisfying the fluctuation theorem comes from the steady-state distribution asymmetry for odd-parity variables, which is activated in a non-transient manner. The latter two parts combine together as the house-keeping (adiabatic) contribution, whose positivity is not guaranteed except when the excess contribution completely vanishes. Our finding reveals that the equilibrium requires the steady-state distribution symmetry for odd-parity variables independently, in addition to the usual detailed balance. This work was supported by Mid-career Researcher Program through NRF grant (No. 2010-0026627) funded by the MEST.

  10. Anaerobic sludge digestion with a biocatalytic additive

    SciTech Connect

    Ghosh, S.; Henry, M.P.; Fedde, P.A.

    1982-01-01

    The objective of this research was to evaluate the effects of a lactobacillus additive an anaerobic sludge digestion under normal, variable, and overload operating conditions. The additive was a whey fermentation product of an acid-tolerant strain of Lactobacillus acidophilus fortified with CaCO/sub 3/, (NH/sub 4/)/sub 2/HPO/sub 4/, ferrous lactate, and lactic acid. The lactobacillus additive is multifunctional in nature and provides growth factors, metabolic intermediates, and enzymes needed for substrate degradation and cellular synthesis. The experimental work consisted of several pairs of parallel mesophilic (35/sup 0/C) digestion runs (control and test) conducted in five experimental phases. Baseline runs without the additive showed that the two experimental digesters had the same methane content, gas production rate (GPR), and ethane yield. The effect of the additive was to increase methane yield and GPR by about 5% (which was statistically significant) during digester operation at a loading rate (LR) of 3.2 kg VS/m/sup 3/-day and a hydraulic retention time (HRT) of 14 days. Data collected from the various experimental phases showed that the biochemical additive increased methane yield, gas production rate, and VS reduction, and decreased volatile acids accumulation. In addition, it enhanced digester buffer capacity and improved the fertilizer value and dewatering characteristics of the digested residue.

  11. Degradation of DNA damage-independently stalled RNA polymerase II is independent of the E3 ligase Elc1.

    PubMed

    Karakasili, Eleni; Burkert-Kautzsch, Cornelia; Kieser, Anja; Sträßer, Katja

    2014-01-01

    Transcription elongation is a highly dynamic and discontinuous process, which includes frequent pausing of RNA polymerase II (RNAPII). RNAPII complexes that stall persistently on a gene during transcription elongation block transcription and thus have to be removed. It has been proposed that the cellular pathway for removal of these DNA damage-independently stalled RNAPII complexes is similar or identical to the removal of RNAPII complexes stalled due to DNA damage. Here, we show that-consistent with previous data-DNA damage-independent stalling causes polyubiquitylation and proteasome-mediated degradation of Rpb1, the largest subunit of RNAPII, using Saccharomyces cerevisiae as model system. Moreover, recruitment of the proteasome to RNAPII and transcribed genes is increased when transcription elongation is impaired indicating that Rpb1 degradation takes place at the gene. Importantly, in contrast to the DNA damage-dependent pathway Rpb1 degradation of DNA damage-independently stalled RNAPII is independent of the E3 ligase Elc1. In addition, deubiquitylation of RNAPII is also independent of the Elc1-antagonizing deubiquitylase Ubp3. Thus, the pathway for degradation of DNA damage-independently stalled RNAPII is overlapping yet distinct from the previously described pathway for degradation of RNAPII stalled due to DNA damage. Taken together, we provide the first evidence that the cell discriminates between DNA damage-dependently and -independently stalled RNAPII.

  12. Environmental Variables as Predictors of Academic Performance.

    ERIC Educational Resources Information Center

    Henderson, Ronald W.

    This project used six environmental variables identified by Dave (1963) and Wolf (1964) and three additional variables (identification with models, range of social interaction, and perception of practical value of education) to predict academic achievement in six-year-old Mexican-American children from an economically depressed area. The children…

  13. The SU(2) action-angle variables

    NASA Technical Reports Server (NTRS)

    Ellinas, Demosthenes

    1993-01-01

    Operator angle-action variables are studied in the frame of the SU(2) algebra, and their eigenstates and coherent states are discussed. The quantum mechanical addition of action-angle variables is shown to lead to a noncommutative Hopf algebra. The group contraction is used to make the connection with the harmonic oscillator.

  14. Calibration Variable Selection and Natural Zero Determination for Semispan and Canard Balances

    NASA Technical Reports Server (NTRS)

    Ulbrich, Norbert M.

    2013-01-01

    Independent calibration variables for the characterization of semispan and canard wind tunnel balances are discussed. It is shown that the variable selection for a semispan balance is determined by the location of the resultant normal and axial forces that act on the balance. These two forces are the first and second calibration variable. The pitching moment becomes the third calibration variable after the normal and axial forces are shifted to the pitch axis of the balance. Two geometric distances, i.e., the rolling and yawing moment arms, are the fourth and fifth calibration variable. They are traditionally substituted by corresponding moments to simplify the use of calibration data during a wind tunnel test. A canard balance is related to a semispan balance. It also only measures loads on one half of a lifting surface. However, the axial force and yawing moment are of no interest to users of a canard balance. Therefore, its calibration variable set is reduced to the normal force, pitching moment, and rolling moment. The combined load diagrams of the rolling and yawing moment for a semispan balance are discussed. They may be used to illustrate connections between the wind tunnel model geometry, the test section size, and the calibration load schedule. Then, methods are reviewed that may be used to obtain the natural zeros of a semispan or canard balance. In addition, characteristics of three semispan balance calibration rigs are discussed. Finally, basic requirements for a full characterization of a semispan balance are reviewed.

  15. Mindfulness and integrative self-knowledge: relationships with health-related variables.

    PubMed

    Ghasemipour, Yadollah; Robinson, Julie Ann; Ghorbani, Nima

    2013-01-01

    This study examined how mindfulness and integrative self-knowledge were related to health-related issues. Men in general population (n = 103) and coronary heart disease samples (n = 101) completed the Mindful Attention Awareness Scale, the Integrative Self-knowledge Scale, the Type 2 subscale of the Interpersonal Reactions Inventory, the Perceived Stress Scale, and the Anxiety and Depression Scales. In both samples, there was a moderate positive correlation between mindfulness and integrative self-knowledge and they were negatively correlated with all health-related variables. However, only integrative self-knowledge explained independent variance in health-related variables. Specifically, in both samples, the relationship between mindfulness and health-related variables was mediated by integrative self-knowledge. Mindfulness and integrative self-knowledge are related domains of self-awareness that are associated with a range of health-related variables. These relationships are robust across samples drawn from general population and patients with coronary heart disease. The finding that integrative self-knowledge explained additional variance in the health-related variables after the contribution of mindfulness had been accounted for suggests that reflective self-awareness in integrative self-knowledge may make a unique contribution to the explanation of individual differences in health variables.

  16. Independent Predictors of Delay in Emergence From General Anesthesia

    PubMed Central

    Maeda, Shigeru; Tomoyasu, Yumiko; Higuchi, Hitoshi; Ishii-Maruhama, Minako; Egusa, Masahiko; Miyawaki, Takuya

    2015-01-01

    Some patients with intellectual disabilities spend longer than others in emergence from ambulatory general anesthesia for dental treatment. Although antiepileptic drugs and anesthetics might be involved, an independent predictor for delay of the emergence remains unclear. Thus, a purpose of this study is to identify independent factors affecting the delay of emergence from general anesthesia. This was a retrospective cohort study in dental patients with intellectual disabilities. Patients in need of sedative premedication were removed from participants. The outcome was time until emergence from general anesthesia. Stepwise multivariate regression analysis was used to extract independent factors affecting the outcome. Antiepileptic drugs and anesthetic parameters were included as predictor variables. The study included 102 cases. Clobazam, clonazepam, and phenobarbital were shown to be independent determinants of emergence time. Parameters relating to anesthetics, patients' backgrounds, and dental treatment were not independent factors. Delay in emergence time in ambulatory general anesthesia is likely to be related to the antiepileptic drugs of benzodiazepine or barbiturates in patients with intellectual disability. PMID:25849468

  17. Latent variable models with nonparametric interaction effects of latent variables.

    PubMed

    Song, Xinyuan; Lu, Zhaohua; Feng, Xiangnan

    2014-05-10

    Renal disease is one of the common complications of diabetes, especially for Asian populations. Moreover, cardiovascular and renal diseases share common risk factors. This paper proposes a latent variable model with nonparametric interaction effects of latent variables for a study based on the Hong Kong Diabetes Registry, which was established in 1995 as part of a continuous quality improvement program at the Prince of Wales Hospital in Hong Kong. Renal outcome (outcome latent variable) is regressed in terms of cardiac function and diabetes (explanatory latent variables) through an additive structural equation formulated using a series of unspecified univariate and bivariate smooth functions. The Bayesian P-splines approach, along with a Markov chain Monte Carlo algorithm, is proposed to estimate smooth functions, unknown parameters, and latent variables in the model. The performance of the developed methodology is demonstrated via a simulation study. The effect of the nonparametric interaction of cardiac function and diabetes on renal outcome is investigated using the proposed methodology. PMID:24338916

  18. A convenient set of comoving cosmological variables and their application

    NASA Astrophysics Data System (ADS)

    Martel, Hugo; Shapiro, Paul R.

    1998-06-01

    A set of cosmological variables, which we shall refer to as `supercomoving variables', are presented which are an alternative to the standard comoving variables, particularly useful for describing the gas dynamics of cosmic structure formation. For an ideal gas with a ratio of specific heats gamma=5/3, the supercomoving position, velocity and thermodynamic properties (i.e. density, temperature and pressure) of matter are constant in time in a uniform, isotropic, adiabatically expanding universe. Expressed in terms of these supercomoving variables, the non-relativistic, cosmological fluid conservation equations of the Newtonian approximation and the Poisson equation closely resemble their non-cosmological counterparts. This makes it possible to generalize non-cosmological results and techniques to address problems involving departures from uniform, adiabatic Hubble expansion in a straightforward way, for a wide range of cosmological models. These variables were initially introduced by Shandarin to describe structure formation in matter-dominated models. In this paper, we generalize supercomoving variables to models with a uniform contribution to the energy density corresponding to a non-zero cosmological constant, domain walls, cosmic strings, a non-clumping form of non-relativistic matter (e.g. massive neutrinos in the presence of primordial density fluctuations of small wavelength) or a radiation background. Each model is characterized by the value of the density parameter Omega_0 of the non-relativistic matter component in which density fluctuation is possible, and the density parameter Omega_X0 of the additional non-clumping component. For each type of non-clumping background, we identify families within which different values of Omega_0 and Omega_X0 lead to fluid equations and solutions in supercomoving variables which are independent of the cosmological parameters Omega_0 and Omega_X0. We also generalize the description to include the effects of non

  19. Autonomic dysfunction independently predicts poor cardiovascular outcomes in asymptomatic individuals with type 2 diabetes in the DIAD study

    PubMed Central

    Wackers, Frans JTh; Inzucchi, Silvio E; Jose, Powell; Weiss, Curtis; Davey, Janice A; Heller, Gary V; Iskandrian, Ami E; Young, Lawrence H

    2015-01-01

    Objective: The primary aim of this secondary analysis was to determine whether cardiac autonomic neuropathy independently predicted adverse cardiac outcomes in asymptomatic individuals with type 2 diabetes. Additional aims include the determination of the correlation of standard autonomic testing measures and power spectral analysis of heart rate variability, and the association of diabetes-related and cardiac risk factors with cardiac autonomic neuropathy measures. Methods: Cardiac autonomic neuropathy was assessed at the study entry into the Detection of Ischemia in Asymptomatic Diabetics study, using autonomic heart rate and blood pressure testing, and power spectral analysis of heart rate variability. All participants were prospectively followed for the composite clinical outcome of cardiac death, acute coronary syndromes, heart failure, or coronary revascularization. Results: Over 5 years of follow-up, 94 of 1119 (8.4%) subjects developed symptomatic cardiac disease. In unadjusted bivariate analyses, abnormalities in several cardiac autonomic neuropathy tests, including lower Valsalva and Standing Heart Rate Ratios, higher resting Heart Rate, greater systolic blood pressure decrease on standing, and lower low-frequency power, were predictive of symptomatic disease. Independent predictors of poor cardiac outcome were a lower Valsalva Heart Rate Ratio, non-Black ethnicity, longer diabetes duration, higher glycated hemoglobin (HbA1c), insulin use, reported numbness in the extremities, higher pulse pressure, family history of coronary artery disease, and higher waist-to-hip ratio. Clinical factors independently associated with a lower Valsalva Heart Rate Ratio were insulin use, clinical proteinuria, higher pulse pressure, use of angiotensin-converting enzyme inhibitor and non-Black ethnicity. Conclusion: Cardiac autonomic neuropathy predicted adverse cardiac outcomes in asymptomatic type 2 diabetes without known cardiac disease. Clinical variables may help to

  20. Variable Valve Actuation

    SciTech Connect

    Jeffrey Gutterman; A. J. Lasley

    2008-08-31

    Many approaches exist to enable advanced mode, low temperature combustion systems for diesel engines - such as premixed charge compression ignition (PCCI), Homogeneous Charge Compression Ignition (HCCI) or other HCCI-like combustion modes. The fuel properties and the quantity, distribution and temperature profile of air, fuel and residual fraction in the cylinder can have a marked effect on the heat release rate and combustion phasing. Figure 1 shows that a systems approach is required for HCCI-like combustion. While the exact requirements remain unclear (and will vary depending on fuel, engine size and application), some form of substantially variable valve actuation is a likely element in such a system. Variable valve actuation, for both intake and exhaust valve events, is a potent tool for controlling the parameters that are critical to HCCI-like combustion and expanding its operational range. Additionally, VVA can be used to optimize the combustion process as well as exhaust temperatures and impact the after treatment system requirements and its associated cost. Delphi Corporation has major manufacturing and product development and applied R&D expertise in the valve train area. Historical R&D experience includes the development of fully variable electro-hydraulic valve train on research engines as well as several generations of mechanical VVA for gasoline systems. This experience has enabled us to evaluate various implementations and determine the strengths and weaknesses of each. While a fully variable electro-hydraulic valve train system might be the 'ideal' solution technically for maximum flexibility in the timing and control of the valve events, its complexity, associated costs, and high power consumption make its implementation on low cost high volume applications unlikely. Conversely, a simple mechanical system might be a low cost solution but not deliver the flexibility required for HCCI operation. After modeling more than 200 variations of the

  1. Caspase-independent cell deaths.

    PubMed

    Lockshin, Richard A; Zakeri, Zahra

    2002-12-01

    A very common and the best understood of the mechanisms of physiological cell death is apoptosis, resulting from the activation, through either of two primary pathways, of site-specific proteases called caspases. There are, however, many other routes to cell death, prominently including autophagy and proteasomal degradation of critical constituents of cells. These routes are frequently seen in experimental situations in which initiator or effector caspases are inhibited or blocked through genetic means, but they are also encountered during normal physiological and pathological processes. Most frequently, autophagic or proteasomal degradation is used to eliminate massive cytoplasm of very large cells, especially post-mitotic cells, and these pathways are prominent even though caspase genes, messages, and pro-enzymes are found in the cells. These forms of cell death are fully physiological and not simply a default pathway for a defective cell; and they are distinct from necrosis. We do not yet understand the extent to which the pathways are linked, what mechanisms trigger the caspase-independent deaths, and how the choices are made.

  2. Preprototype independent air revitalization subsystem

    NASA Technical Reports Server (NTRS)

    Schubert, F. H.; Hallick, T. M.; Woods, R. R.

    1982-01-01

    The performance and maturity of a preprototype, three-person capacity, automatically controlled and monitored, self-contained independent air revitalization subsystem were evaluated. The subsystem maintains the cabin partial pressure of oxygen at 22 kPa (3.2 psia) and that of carbon dioxide at 400 Pa (3 mm Hg) over a wide range of cabin air relative humidity conditions. Consumption of water vapor by the water vapor electrolysis module also provides partial humidity control of the cabin environment. During operation, the average carbon dioxide removal efficiency at baseline conditions remained constant throughout the test at 84%. The average electrochemical depolarized concentrator cell voltage at the end of the parametric/endurance test was 0.41 V, representing a very slowly decreasing average cell voltage. The average water vapor electrolysis cell voltage increased only at a rate of 20 mu/h from the initial level of 1.67 V to the final level of 1.69 V at conclusion of the testing.

  3. Cognitive Variables in Problem Solving: A Nonlinear Approach

    ERIC Educational Resources Information Center

    Stamovlasis, Dimitrios; Tsaparlis, Georgios

    2005-01-01

    We employ tools of complexity theory to examine the effect of cognitive variables, such as working-memory capacity, degree of field dependence-independence, developmental level and the mobility-fixity dimension. The nonlinear method correlates the subjects' rank-order achievement scores with each cognitive variable. From the achievement scores in…

  4. Effect of two natural light regimes and nutrient addition on the forest herb Begonia decandra (Begoniaceae).

    PubMed

    Cordero, R A

    2000-01-01

    The effect of two natural light-growing conditions (understory versus light gaps) and the interaction with nutrient availability (through fertilization) were studied in the understory herb Begonia decandra, in the Luquillo Experimental Forest in Puerto Rico. Sixteen potted plants obtained from cuttings were randomly chosen and distributed in each of eighth forest environments (four light gaps and four understories), for a total of 128 plants. Fertilizer was applied to half of the plants in each site. After seven months in the two given microenvironments, increased light and fertilization resulted in greater growth and some changes in the biomass allocation patterns. All measured variables responded similarly to reported changes for tree seedlings and saplings from other tropical and subtropical regions. Total growth parameters (height, biomass and leaf area) were very sensitive to increases in the main resource (light). The addition of nutrients was less important in producing changes in the allocation variables (root to shoot ratio, leaf area ratio, and specific leaf mass) under conditions of high light availability. Changes due to nutrient levels were relatively greater on plants grown under under-story conditions. Also, small light differences among sites can cause significant changes in the variables related to total growth. Lastly, plant mortality in the nutrient treatments was found to be independent of mortality in two forest light environments. Some hypotheses about resource acquisition and plant growth are not supported by this data.

  5. Variability as an Operant?

    ERIC Educational Resources Information Center

    Holth, Per

    2012-01-01

    A series of experiments on operant variability by Neuringer and colleagues (e.g., Neuringer, 1986, 2002; Page & Neuringer, 1985) have been repeatedly cited as showing that behavioral variability can be reinforced by making reinforcement contingent on it. They showed that the degree of variability in pigeons' eight-peck sequences, as measured by U…

  6. Variable volume maser techniques

    NASA Technical Reports Server (NTRS)

    Reinhardt, V. S.

    1977-01-01

    The frequency stability of hydrogen masers in variable volume storage bulbs is discussed in terms of wall shift. Variable volume devices discussed include: Brenner flexible bulb, Debely device, and the concertina hydrogen maser. A flexible cone variable volume element outside the cavity is described.

  7. Learning Dilemmas in Undergraduate Student Independent Essays

    ERIC Educational Resources Information Center

    Wendt, Maria; Åse, Cecilia

    2015-01-01

    Essay-writing is generally viewed as the primary learning activity to foster independence and analytical thinking. In this article, we show that independent research projects do not necessarily lead to critical thinking. University-level education on conducting independent projects can, in several respects, counteract enhanced analytical skills.…

  8. Independence, Individualism & Connection among Share Householders

    ERIC Educational Resources Information Center

    Natalier, Kristin

    2007-01-01

    How do young people who are financially dependent on their parents but living in share households conceive of the concept of independence? The meanings of independence are discussed in relation to a qualitative study of young people who described themselves as independent although they accepted money on a regular basis from their parents. Their…

  9. 45 CFR 1309.44 - Independent analysis.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 45 Public Welfare 4 2013-10-01 2013-10-01 false Independent analysis. 1309.44 Section 1309.44... § 1309.44 Independent analysis. (a) The responsible HHS official may direct the grantee applying for funds to acquire or make major renovations to a facility to obtain an independent analysis of the...

  10. 45 CFR 1309.44 - Independent analysis.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 4 2012-10-01 2012-10-01 false Independent analysis. 1309.44 Section 1309.44... § 1309.44 Independent analysis. (a) The responsible HHS official may direct the grantee applying for funds to acquire or make major renovations to a facility to obtain an independent analysis of the...

  11. 45 CFR 1309.44 - Independent analysis.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 4 2014-10-01 2014-10-01 false Independent analysis. 1309.44 Section 1309.44... § 1309.44 Independent analysis. (a) The responsible HHS official may direct the grantee applying for funds to acquire or make major renovations to a facility to obtain an independent analysis of the...

  12. 45 CFR 1309.44 - Independent analysis.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 4 2011-10-01 2011-10-01 false Independent analysis. 1309.44 Section 1309.44... § 1309.44 Independent analysis. (a) The responsible HHS official may direct the grantee applying for funds to acquire or make major renovations to a facility to obtain an independent analysis of the...

  13. 45 CFR 1309.44 - Independent analysis.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Independent analysis. 1309.44 Section 1309.44... § 1309.44 Independent analysis. (a) The responsible HHS official may direct the grantee applying for funds to acquire or make major renovations to a facility to obtain an independent analysis of the...

  14. Independent Evaluation: Insights from Public Accounting

    ERIC Educational Resources Information Center

    Brown, Abigail B.; Klerman, Jacob Alex

    2012-01-01

    Background: Maintaining the independence of contract government program evaluation presents significant contracting challenges. The ideal outcome for an agency is often both the impression of an independent evaluation "and" a glowing report. In this, independent evaluation is like financial statement audits: firm management wants both a public…

  15. 46 CFR 62.30-5 - Independence.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... instrumentation systems for any vital system must be independent of each other. (2) Independent sensors are not required except that sensors for primary speed, pitch, or direction of rotation control in closed loop..., or instrumentation sensors. (3) The safety trip control of § 62.35-5(b)(2) must be independent...

  16. 32 CFR 169a.16 - Independent review.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 1 2013-07-01 2013-07-01 false Independent review. 169a.16 Section 169a.16... ACTIVITIES PROGRAM PROCEDURES Procedures § 169a.16 Independent review. (a) The estimates of in-house and..., independent of the Task Group preparing the cost comparison. This review shall be completed far enough...

  17. 7 CFR 1218.55 - Independent evaluation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Independent evaluation. 1218.55 Section 1218.55... § 1218.55 Independent evaluation. The Council shall, not less often than every five years, authorize and fund, from funds otherwise available to the Council, an independent evaluation of the effectiveness...

  18. 7 CFR 1212.61 - Independent evaluation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Independent evaluation. 1212.61 Section 1212.61... Independent evaluation. The Board must authorize and fund not less than once every five years an independent evaluation of the effectiveness of this subpart and the plans and programs conducted by the Board under...

  19. 7 CFR 1212.61 - Independent evaluation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Independent evaluation. 1212.61 Section 1212.61... Independent evaluation. The Board must authorize and fund not less than once every five years an independent evaluation of the effectiveness of this subpart and the plans and programs conducted by the Board under...

  20. 7 CFR 1214.61 - Independent evaluation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Independent evaluation. 1214.61 Section 1214.61..., Research and Information § 1214.61 Independent evaluation. The Board shall, not less often than once every five years, authorize and fund, from funds otherwise available to the Board, an independent...

  1. 7 CFR 1216.53 - Independent evaluation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Independent evaluation. 1216.53 Section 1216.53... Independent evaluation. The Board shall, not less often than every five years, authorize and fund, from funds otherwise available to the Board, an independent evaluation of the effectiveness of the Order and...

  2. 7 CFR 1218.55 - Independent evaluation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Independent evaluation. 1218.55 Section 1218.55... § 1218.55 Independent evaluation. The Council shall, not less often than every five years, authorize and fund, from funds otherwise available to the Council, an independent evaluation of the effectiveness...

  3. Independent Study Unit for Exceptional Students.

    ERIC Educational Resources Information Center

    Brown, Marleen; And Others

    The program is designed to provide an opportunity in independent study for junior high school students with high ability and motivation. The independent study program is undertaken with the guidance of an advisor. Four independent study activities offered to the student are: write a research paper on Arizona history, government, U.S. History, and…

  4. 46 CFR 62.30-5 - Independence.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... instrumentation systems for any vital system must be independent of each other. (2) Independent sensors are not required except that sensors for primary speed, pitch, or direction of rotation control in closed loop..., or instrumentation sensors. (3) The safety trip control of § 62.35-5(b)(2) must be independent...

  5. 46 CFR 62.30-5 - Independence.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... instrumentation systems for any vital system must be independent of each other. (2) Independent sensors are not required except that sensors for primary speed, pitch, or direction of rotation control in closed loop..., or instrumentation sensors. (3) The safety trip control of § 62.35-5(b)(2) must be independent...

  6. 46 CFR 62.30-5 - Independence.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... instrumentation systems for any vital system must be independent of each other. (2) Independent sensors are not required except that sensors for primary speed, pitch, or direction of rotation control in closed loop..., or instrumentation sensors. (3) The safety trip control of § 62.35-5(b)(2) must be independent...

  7. 46 CFR 62.30-5 - Independence.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... instrumentation systems for any vital system must be independent of each other. (2) Independent sensors are not required except that sensors for primary speed, pitch, or direction of rotation control in closed loop..., or instrumentation sensors. (3) The safety trip control of § 62.35-5(b)(2) must be independent...

  8. Large Independent Primary Care Medical Groups

    PubMed Central

    Casalino, Lawrence P.; Chen, Melinda A.; Staub, C. Todd; Press, Matthew J.; Mendelsohn, Jayme L.; Lynch, John T.; Miranda, Yesenia

    2016-01-01

    PURPOSE In the turbulent US health care environment, many primary care physicians seek hospital employment. Large physician-owned primary care groups are an alternative, but few physicians or policy makers realize that such groups exist. We wanted to describe these groups, their advantages, and their challenges. METHODS We identified 21 groups and studied 5 that varied in size and location. We conducted interviews with group leaders, surveyed randomly selected group physicians, and interviewed external observers—leaders of a health plan, hospital, and specialty medical group that shared patients with the group. We triangulated responses from group leaders, group physicians, and external observers to identify key themes. RESULTS The groups’ physicians work in small practices, with the group providing economies of scale necessary to develop laboratory and imaging services, health information technology, and quality improvement infrastructure. The groups differ in their size and the extent to which they engage in value-based contracting, though all are moving to increase the amount of financial risk they take for their quality and cost performance. Unlike hospital-employed and multispecialty groups, independent primary care groups can aim to reduce health care costs without conflicting incentives to fill hospital beds and keep specialist incomes high. Each group was positively regarded by external observers. The groups are under pressure, however, to sell to organizations that can provide capital for additional infrastructure to engage in value-based contracting, as well as provide substantial income to physicians from the sale. CONCLUSIONS Large, independent primary care groups have the potential to make primary care attractive to physicians and to improve patient care by combining human scale advantages of physician autonomy and the small practice setting with resources that are important to succeed in value-based contracting. PMID:26755779

  9. Orientation-independent measures of ground motion

    USGS Publications Warehouse

    Boore, D.M.; Watson-Lamprey, Jennie; Abrahamson, N.A.

    2006-01-01

    The geometric mean of the response spectra for two orthogonal horizontal components of motion, commonly used as the response variable in predictions of strong ground motion, depends on the orientation of the sensors as installed in the field. This means that the measure of ground-motion intensity could differ for the same actual ground motion. This dependence on sensor orientation is most pronounced for strongly correlated motion (the extreme example being linearly polarized motion), such as often occurs at periods of 1 sec or longer. We propose two new measures of the geometric mean, GMRotDpp, and GMRotIpp, that are independent of the sensor orientations. Both are based on a set of geometric means computed from the as-recorded orthogonal horizontal motions rotated through all possible non-redundant rotation angles. GMRotDpp is determined as the ppth percentile of the set of geometric means for a given oscillator period. For example, GMRotDOO, GMRotD50, and GMRotD100 correspond to the minimum, median, and maximum values, respectively. The rotations that lead to GMRotDpp depend on period, whereas a single-period-independent rotation is used for GMRotIpp, the angle being chosen to minimize the spread of the rotation-dependent geometric mean (normalized by GMRotDpp) over the usable range of oscillator periods. GMRotI50 is the ground-motion intensity measure being used in the development of new ground-motion prediction equations by the Pacific Earthquake Engineering Center Next Generation Attenuation project. Comparisons with as-recorded geometric means for a large dataset show that the new measures are systematically larger than the geometric-mean response spectra using the as-recorded values of ground acceleration, but only by a small amount (less than 3%). The theoretical advantage of the new measures is that they remove sensor orientation as a contributor to aleatory uncertainty. Whether the reduction is of practical significance awaits detailed studies of large

  10. Alignment independent 3D-QSAR, quantum calculations and molecular docking of Mer specific tyrosine kinase inhibitors as anticancer drugs

    PubMed Central

    Shiri, Fereshteh; Pirhadi, Somayeh; Ghasemi, Jahan B.

    2015-01-01

    Mer receptor tyrosine kinase is a promising novel cancer therapeutic target in many human cancers, because abnormal activation of Mer has been implicated in survival signaling and chemoresistance. 3D-QSAR analyses based on alignment independent descriptors were performed on a series of 81 Mer specific tyrosine kinase inhibitors. The fractional factorial design (FFD) and the enhanced replacement method (ERM) were applied and tested as variable selection algorithms for the selection of optimal subsets of molecular descriptors from a much greater pool of such regression variables. The data set was split into 65 molecules as the training set and 16 compounds as the test set. All descriptors were generated by using the GRid INdependent descriptors (GRIND) approach. After variable selection, GRIND were correlated with activity values (pIC50) by PLS regression. Of the two applied variable selection methods, ERM had a noticeable improvement on the statistical parameters of PLS model, and yielded a q2 value of 0.77, an rpred2 of 0.94, and a low RMSEP value of 0.25. The GRIND information contents influencing the affinity on Mer specific tyrosine kinase were also confirmed by docking studies. In a quantum calculation study, the energy difference between HOMO and LUMO (gap) implied the high interaction of the most active molecule in the active site of the protein. In addition, the molecular electrostatic potential energy at DFT level confirmed results obtained from the molecular docking. The identified key features obtained from the molecular modeling, enabled us to design novel kinase inhibitors. PMID:27013913

  11. Variable cycle engines for advanced supersonic transports

    NASA Technical Reports Server (NTRS)

    Howlett, R. A.; Kozlowski, H.

    1975-01-01

    Variable Cycle Engines being studied for advanced commercial supersonic transports show potential for significant environmental and economic improvements relative to 1st generation SST engines. The two most promising concepts are: a Variable Stream Control Engine and a Variable Cycle Engine with a rear flow-control valve. Each concept utilizes variable components and separate burners to provide independent temperature and velocity control for two coannular flow streams. Unique fuel control techniques are combined with cycle characteristics that provide low fuel consumption, similar to a turbojet engine, for supersonic operation. This is accomplished while retaining the good subsonic performance features of a turbofan engine. A two-stream coannular nozzle shows potential to reduce jet noise to below FAR Part 36 without suppressors. Advanced burner concepts have the potential for significant reductions in exhaust emissions. In total, these unique engine concepts have the potential for significant overall improvements to the environmental and economic characteristics of advanced supersonic transports.

  12. Independent Orbiter Assessment (IOA): Assessment of the pyrotechnics subsystem

    NASA Technical Reports Server (NTRS)

    Robinson, W. M.

    1988-01-01

    The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Pyrotechnics (PYRO) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter Pyrotechnics hardware.

  13. Independent component analysis for improving the quality of interferometric products

    NASA Astrophysics Data System (ADS)

    Saqellari Likoka, A.; Vafeiadi-Bila, E.; Karathanassi, V.

    2016-05-01

    The accuracy of InSAR DEMs is affected by the temporal decorrelation of SAR images which is due to atmosphere, land use/cover, soil moisture, and roughness changes. Elimination of the temporal decorrelation of the master and slave image improves the DEMs accuracy. In this study, the Independent Component Analysis was applied before interferometric process. It was observed that using three ICA entries, ICA independent sources can be interpreted as background and changed images. ICA when performed on the master and slave images using the same couple of additional images produces two background images which enable the production of high quality DEMs. However, limitations exist in the proposed approach.

  14. Why a variable G. [strong equivalence principle applied to study of variable G star

    NASA Technical Reports Server (NTRS)

    Canuto, V. M.; Goldman, I.

    1982-01-01

    An attempt is made to put the possible time variability of G in a broader context. It is suggested that the variable G is a popular and incomplete representation of the problem of the validity of the strong equivalence principle (SEP). Particular reference is made to a reanalysis of Viking Mars data to study, in a model independent way, the influence of atomic clocks in recording purely gravitational phenomena. These data ought to provide the most reliable test of the variability of G and the validity of the SEP.

  15. Independent rate and temporal coding in hippocampal pyramidal cells

    PubMed Central

    Huxter, John; Burgess, Neil; O’Keefe, John

    2009-01-01

    Hippocampal pyramidal cells use temporal 1 as well as rate coding 2 to signal spatial aspects of the animal’s environment or behaviour. The temporal code takes the form of a phase relationship to the concurrent cycle of the hippocampal EEG theta rhythm (Figure 1​; 1). These two codes could each represent a different variable 3,4. However, this requires that rate and phase can vary independently, in contrast to recent suggestions 5,6 that they are tightly coupled: both reflecting the amplitude of the cell’s input. Here we show that the time of firing and firing rate are dissociable and can represent two independent variables, viz, the animal’s location within the place field and its speed of movement through the field, respectively. Independent encoding of location together with actions and stimuli occurring there may help to explain the dual roles of the hippocampus in spatial and episodic memory 7 8 or a more general role in relational/declarative memory9,10. PMID:14574410

  16. A comparison of absolute performance of different correlative and mechanistic species distribution models in an independent area.

    PubMed

    Shabani, Farzin; Kumar, Lalit; Ahmadi, Mohsen

    2016-08-01

    To investigate the comparative abilities of six different bioclimatic models in an independent area, utilizing the distribution of eight different species available at a global scale and in Australia. Global scale and Australia. We tested a variety of bioclimatic models for eight different plant species employing five discriminatory correlative species distribution models (SDMs) including Generalized Linear Model (GLM), MaxEnt, Random Forest (RF), Boosted Regression Tree (BRT), Bioclim, together with CLIMEX (CL) as a mechanistic niche model. These models were fitted using a training dataset of available global data, but with the exclusion of Australian locations. The capabilities of these techniques in projecting suitable climate, based on independent records for these species in Australia, were compared. Thus, Australia is not used to calibrate the models and therefore it is as an independent area regarding geographic locations. To assess and compare performance, we utilized the area under the receiver operating characteristic (ROC) curves (AUC), true skill statistic (TSS), and fractional predicted areas for all SDMs. In addition, we assessed satisfactory agreements between the outputs of the six different bioclimatic models, for all eight species in Australia. The modeling method impacted on potential distribution predictions under current climate. However, the utilization of sensitivity and the fractional predicted areas showed that GLM, MaxEnt, Bioclim, and CL had the highest sensitivity for Australian climate conditions. Bioclim calculated the highest fractional predicted area of an independent area, while RF and BRT were poor. For many applications, it is difficult to decide which bioclimatic model to use. This research shows that variable results are obtained using different SDMs in an independent area. This research also shows that the SDMs produce different results for different species; for example, Bioclim may not be good for one species but works better

  17. A comparison of absolute performance of different correlative and mechanistic species distribution models in an independent area.

    PubMed

    Shabani, Farzin; Kumar, Lalit; Ahmadi, Mohsen

    2016-08-01

    To investigate the comparative abilities of six different bioclimatic models in an independent area, utilizing the distribution of eight different species available at a global scale and in Australia. Global scale and Australia. We tested a variety of bioclimatic models for eight different plant species employing five discriminatory correlative species distribution models (SDMs) including Generalized Linear Model (GLM), MaxEnt, Random Forest (RF), Boosted Regression Tree (BRT), Bioclim, together with CLIMEX (CL) as a mechanistic niche model. These models were fitted using a training dataset of available global data, but with the exclusion of Australian locations. The capabilities of these techniques in projecting suitable climate, based on independent records for these species in Australia, were compared. Thus, Australia is not used to calibrate the models and therefore it is as an independent area regarding geographic locations. To assess and compare performance, we utilized the area under the receiver operating characteristic (ROC) curves (AUC), true skill statistic (TSS), and fractional predicted areas for all SDMs. In addition, we assessed satisfactory agreements between the outputs of the six different bioclimatic models, for all eight species in Australia. The modeling method impacted on potential distribution predictions under current climate. However, the utilization of sensitivity and the fractional predicted areas showed that GLM, MaxEnt, Bioclim, and CL had the highest sensitivity for Australian climate conditions. Bioclim calculated the highest fractional predicted area of an independent area, while RF and BRT were poor. For many applications, it is difficult to decide which bioclimatic model to use. This research shows that variable results are obtained using different SDMs in an independent area. This research also shows that the SDMs produce different results for different species; for example, Bioclim may not be good for one species but works better

  18. Nova-like variables

    NASA Technical Reports Server (NTRS)

    Ladous, Constanze

    1993-01-01

    On grounds of different observable characteristics five classes of nova-like objects are distinguished: the UX Ursae Majoris stars, the antidwarf novae, the DQ Herculis stars, the AM Herculis stars, and the AM Canum Venaticorum stars. Some objects have not been classified specifically. Nova-like stars share most observable features with dwarf novae, except for the outburst behavior. The understanding is that dwarf novae, UX Ursae Majoris stars, and anti-dwarf novae are basically the same sort of objects. The difference between them is that in UX Ursae Majoris stars the mass transfer through the accretion disc always is high so the disc is stationary all the time; in anti-dwarf novae for some reason the mass transfer occasionally drops considerably for some time, and in dwarf novae it is low enough for the disc to undergo semiperiodic changes between high and low accretion events. DQ Herculis stars are believed to possess weakly magnetic white dwarfs which disrupt the inner disc at some distance from the central star; the rotation of the white dwarf can be seen as an additional photometric period. In AM Herculis stars, a strongly magnetic white dwarf entirely prevents the formation of an accretion disk and at the same time locks the rotation of the white dwarf to the binary orbit. Finally, AM Canum Venaticorum stars are believed to be cataclysmic variables that consist of two white dwarf components.

  19. Common Variable Immunodeficiency.

    PubMed

    Saikia, Biman; Gupta, Sudhir

    2016-04-01

    Common variable immunodeficiency (CVID) is the most common primary immunodeficiency of young adolescents and adults which also affects the children. The disease remains largely under-diagnosed in India and Southeast Asian countries. Although in majority of cases it is sporadic, disease may be inherited in a autosomal recessive pattern and rarely, in autosomal dominant pattern. Patients, in addition to frequent sino-pulmonary infections, are also susceptible to various autoimmune diseases and malignancy, predominantly lymphoma and leukemia. Other characteristic lesions include lymphocytic and granulomatous interstitial lung disease, and nodular lymphoid hyperplasia of gut. Diagnosis requires reduced levels of at least two immunoglobulin isotypes: IgG with IgA and/or IgM and impaired specific antibody response to vaccines. A number of gene mutations have been described in CVID; however, these genetic alterations account for less than 20% of cases of CVID. Flow cytometry aptly demonstrates a disturbed B cell homeostasis with reduced or absent memory B cells and increased CD21(low) B cells and transitional B cell populations. Approximately one-third of patients with CVID also display T cell functional defects. Immunoglobulin therapy remains the mainstay of treatment. Immunologists and other clinicians in India and other South East Asian countries need to be aware of CVID so that early diagnosis can be made, as currently, majority of these patients still go undiagnosed. PMID:26868026

  20. Incorporation of additives into polymers

    DOEpatents

    McCleskey, T. Mark; Yates, Matthew Z.

    2003-07-29

    There has been invented a method for incorporating additives into polymers comprising: (a) forming an aqueous or alcohol-based colloidal system of the polymer; (b) emulsifying the colloidal system with a compressed fluid; and (c) contacting the colloidal polymer with the additive in the presence of the compressed fluid. The colloidal polymer can be contacted with the additive by having the additive in the compressed fluid used for emulsification or by adding the additive to the colloidal system before or after emulsification with the compressed fluid. The invention process can be carried out either as a batch process or as a continuous on-line process.

  1. [Patch-testing methods: additional specialised or additional series].

    PubMed

    Cleenewerck, M-B

    2009-01-01

    The tests in the European standard battery must occasionally be supplemented by specialised or additional batteries, particularly where the contact allergy is thought to be of occupational origin. These additional batteries cover all allergens associated with various professional activities (hairdressing, baking, dentistry, printing, etc.) and with different classes of materials and chemical products (glue, plastic, rubber...). These additional tests may also include personal items used by patients on a daily basis such as cosmetics, shoes, plants, textiles and so on.

  2. Theoretical and experimental investigation of additive drag

    NASA Technical Reports Server (NTRS)

    Sibulkin, Merwin

    1954-01-01

    The significance of additive drag is discussed and equations for determining its approximate value are derived for annular and open-nose inlets. Charts are presented giving values of additive drag coefficient over a range of free-stream Mach numbers for open and for annular-nose inlets with conical flow at the inlet. The effects on additive drag of variable inlet-total-pressure recovery and static pressures on the centerbody are investigated and an analytical method of predicting the variation of pressure on the centerbody with mass-flow ratio is given. Experimental additive-drag values are presented for a series of 20 degree and 25 degree cone half-angle inlets and one open-nose inlet operating at free-stream Mach numbers of 1.8 and 1.6. A comparison with the theoretical values of additive drag shows excellent agreement for the open-nose inlet and moderately good agreement for the annular inlets. (author)

  3. Estimation of Baroreflex Function Using Independent Component Analysis of Photoplethysmography

    NASA Astrophysics Data System (ADS)

    Abe, Makoto; Yoshizawa, Makoto; Sugita, Norihiro; Tanaka, Akira; Homma, Noriyasu; Yambe, Tomoyuki; Nitta, Shin-Ichi

    The maximum cross-correlation coefficient ρmax between blood pressure variability and heart rate variability, whose frequency components are limited to the Mayer wave-related band, is a useful index to evaluate the state of the autonomic nervous function related to baroreflex. However, measurement of continuous blood pressure with an expensive and bulky measuring device is required to calculate ρmax. The present study has proposed an easier method for obtaining ρmax with measurement of finger photoplethysmography (PPG) only. In the proposed method, independent components are extracted from feature variables specifying the PPG signal by using the independent component analysis (ICA), and then the most appropriate component is chosen out of them so that the ρmax calculated from the component can approximate its true value. The results from the experiment with a postural change performed in 18 healthy subjects have suggested that the proposed method is available for estimating ρmax by using the ICA to extract blood pressure information from the PPG signal.

  4. Additive manufacturing of optical components

    NASA Astrophysics Data System (ADS)

    Heinrich, Andreas; Rank, Manuel; Maillard, Philippe; Suckow, Anne; Bauckhage, Yannick; Rößler, Patrick; Lang, Johannes; Shariff, Fatin; Pekrul, Sven

    2016-08-01

    The development of additive manufacturing methods has enlarged rapidly in recent years. Thereby, the work mainly focuses on the realization of mechanical components, but the additive manufacturing technology offers a high potential in the field of optics as well. Owing to new design possibilities, completely new solutions are possible. This article briefly reviews and compares the most important additive manufacturing methods for polymer optics. Additionally, it points out the characteristics of additive manufactured polymer optics. Thereby, surface quality is of crucial importance. In order to improve it, appropriate post-processing steps are necessary (e.g. robot polishing or coating), which will be discussed. An essential part of this paper deals with various additive manufactured optical components and their use, especially in optical systems for shape metrology (e.g. borehole sensor, tilt sensor, freeform surface sensor, fisheye lens). The examples should demonstrate the potentials and limitations of optical components produced by additive manufacturing.

  5. The Independent Payment Advisory Board.

    PubMed

    Manchikanti, Laxmaiah; Falco, Frank J E; Singh, Vijay; Benyamin, Ramsin M; Hirsch, Joshua A

    2011-01-01

    The Independent Payment Advisory Board (IPAB) is a vastly powerful component of the president's health care reform law, with authority to issue recommendations to reduce the growth in Medicare spending, providing recommendations to be considered by Congress and implemented by the administration on a fast track basis. Ever since its inception, IPAB has been one of the most controversial issues of the Patient Protection and Affordable Care Act (ACA), even though the powers of IPAB are restricted and multiple sectors of health care have been protected in the law. IPAB works by recommending policies to Congress to help Medicare provide better care at a lower cost, which would include ideas on coordinating care, getting rid of waste in the system, providing incentives for best practices, and prioritizing primary care. Congress then has the power to accept or reject these recommendations. However, Congress faces extreme limitations, either to enact policies that achieve equivalent savings, or let the Secretary of Health and Human Services (HHS) follow IPAB's recommendations. IPAB has strong supporters and opponents, leading to arguments in favor of or against to the extreme of introducing legislation to repeal IPAB. The origins of IPAB are found in the ideology of the National Institute for Health and Clinical Excellence (NICE) and the impetus of exploring health care costs, even though IPAB's authority seems to be limited to Medicare only. The structure and operation of IPAB differs from Medicare and has been called the Medicare Payment Advisory Commission (MedPAC) on steroids. The board membership consists of 15 full-time members appointed by the president and confirmed by the Senate with options for recess appointments. The IPAB statute sets target growth rates for Medicare spending. The applicable percent for maximum savings appears to be 0.5% for year 2015, 1% for 2016, 1.25% for 2017, and 1.5% for 2018 and later. The IPAB Medicare proposal process involves

  6. Smile (System/Machine-Independent Local Environment)

    SciTech Connect

    Fletcher, J.G.

    1988-04-01

    This document defines the characteristics of Smile, a System/machine-independent local environment. This environment consists primarily of a number of primitives (types, macros, procedure calls, and variables) that a program may use; these primitives provide facilities, such as memory allocation, timing, tasking and synchronization beyond those typically provided by a programming language. The intent is that a program will be portable from system to system and from machine to machine if it relies only on the portable aspects of its programming language and on the Smile primitives. For this to be so, Smile itself must be implemented on each system and machine, most likely using non-portable constructions; that is, while the environment provided by Smile is intended to be portable, the implementation of Smile is not necessarily so. In order to make the implementation of Smile as easy as possible and thereby expedite the porting of programs to a new system or a new machine, Smile has been defined to provide a minimal portable environment; that is, simple primitives are defined, out of which more complex facilities may be constructed using portable procedures. The implementation of Smile can be as any of the following: the underlying software environment for the operating system of an otherwise {open_quotes}bare{close_quotes} machine, a {open_quotes}guest{close_quotes} system environment built upon a preexisting operating system, an environment within a {open_quotes}user{close_quotes} process run by an operating system, or a single environment for an entire machine, encompassing both system and {open_quotes}user{close_quotes} processes. In the first three of these cases the tasks provided by Smile are {open_quotes}lightweight processes{close_quotes} multiplexed within preexisting processes or the system, while in the last case they also include the system processes themselves.

  7. Some new addition formulae for Weierstrass elliptic functions

    PubMed Central

    Eilbeck, J. Chris; England, Matthew; Ônishi, Yoshihiro

    2014-01-01

    We present new addition formulae for the Weierstrass functions associated with a general elliptic curve. We prove the structure of the formulae in n-variables and give the explicit addition formulae for the 2- and 3-variable cases. These new results were inspired by new addition formulae found in the case of an equianharmonic curve, which we can now observe as a specialization of the results here. The new formulae, and the techniques used to find them, also follow the recent work for the generalization of Weierstrass functions to curves of higher genus. PMID:25383018

  8. Studying the variability in the Raman signature of writing pen inks.

    PubMed

    Braz, André; López-López, María; García-Ruiz, Carmen

    2014-12-01

    This manuscript aims to study the inter and intra brand, model and batch variability in the Raman spectral signature among modern pen inks that will help forensic document examiners during the interpretation process. Results showed that most oil-based samples have similar Raman signatures that are characteristic of the Crystal Violet dye, independently of the brand. Exception was the Pilot samples that use Victoria Pure Blue BO instead. This small inter-brand variability makes oil-based pens difficult to discriminate by brand. On the contrary, gel and liquid-based samples use different colorants such as Rhodamine B, Copper Phthalocyanine, Ethyl Violet and Victoria Blue B. No particular pattern was observed regarding the colorants used by each brand, except the Pilot samples that were the only brand using the Victoria Blue B dye, which is a clear distinct feature. Additionally, the intra-brand variability was also large among gel-based Pilot samples. The small spectral differences observed among several batches of Bic Crystal Medium samples demonstrated that changes were introduced in their chemical formula over the years. The intra-batch variability was small and no spectral differences were observed within batches. This manuscript demonstrates the potential of Raman spectroscopy for discriminating pens inks from different brands and models and even, batches. Additionally, the main colorants used in modern pens were also identified. PMID:25447172

  9. Fetal autonomic brain age scores, segmented heart rate variability analysis, and traditional short term variability

    PubMed Central

    Hoyer, Dirk; Kowalski, Eva-Maria; Schmidt, Alexander; Tetschke, Florian; Nowack, Samuel; Rudolph, Anja; Wallwitz, Ulrike; Kynass, Isabelle; Bode, Franziska; Tegtmeyer, Janine; Kumm, Kathrin; Moraru, Liviu; Götz, Theresa; Haueisen, Jens; Witte, Otto W.; Schleußner, Ekkehard; Schneider, Uwe

    2014-01-01

    Disturbances of fetal autonomic brain development can be evaluated from fetal heart rate patterns (HRP) reflecting the activity of the autonomic nervous system. Although HRP analysis from cardiotocographic (CTG) recordings is established for fetal surveillance, temporal resolution is low. Fetal magnetocardiography (MCG), however, provides stable continuous recordings at a higher temporal resolution combined with a more precise heart rate variability (HRV) analysis. A direct comparison of CTG and MCG based HRV analysis is pending. The aims of the present study are: (i) to compare the fetal maturation age predicting value of the MCG based fetal Autonomic Brain Age Score (fABAS) approach with that of CTG based Dawes-Redman methodology; and (ii) to elaborate fABAS methodology by segmentation according to fetal behavioral states and HRP. We investigated MCG recordings from 418 normal fetuses, aged between 21 and 40 weeks of gestation. In linear regression models we obtained an age predicting value of CTG compatible short term variability (STV) of R2 = 0.200 (coefficient of determination) in contrast to MCG/fABAS related multivariate models with R2 = 0.648 in 30 min recordings, R2 = 0.610 in active sleep segments of 10 min, and R2 = 0.626 in quiet sleep segments of 10 min. Additionally segmented analysis under particular exclusion of accelerations (AC) and decelerations (DC) in quiet sleep resulted in a novel multivariate model with R2 = 0.706. According to our results, fMCG based fABAS may provide a promising tool for the estimation of fetal autonomic brain age. Beside other traditional and novel HRV indices as possible indicators of developmental disturbances, the establishment of a fABAS score normogram may represent a specific reference. The present results are intended to contribute to further exploration and validation using independent data sets and multicenter research structures. PMID:25505399

  10. Pressure independence of granular flow through an aperture.

    PubMed

    Aguirre, M A; Grande, J G; Calvo, A; Pugnaloni, L A; Géminard, J-C

    2010-06-11

    We experimentally demonstrate that the flow rate of granular material through an aperture is controlled by the exit velocity imposed on the particles and not by the pressure at the base, contrary to what is often assumed in previous work. This result is achieved by studying the discharge process of a dense packing of monosized disks through an orifice. The flow is driven by a conveyor belt. This two-dimensional horizontal setup allows us to independently control the velocity at which the disks escape the horizontal silo and the pressure in the vicinity of the aperture. The flow rate is found to be proportional to the belt velocity, independent of the amount of disks in the container and, thus, independent of the pressure in the outlet region. In addition, this specific configuration makes it possible to get information on the system dynamics from a single image of the disks that rest on the conveyor belt after the discharge. PMID:20867272

  11. Some Statistical Strategies for DAE-seq Data Analysis: Variable Selection and Modeling Dependencies among Observations

    PubMed Central

    Rashid, Naim U.; Sun, Wei; Ibrahim, Joseph G.

    2014-01-01

    In DAE (DNA After Enrichment)-seq experiments, genomic regions related with certain biological processes are enriched/isolated by an assay and are then sequenced on a high-throughput sequencing platform to determine their genomic positions. Statistical analysis of DAE-seq data aims to detect genomic regions with significant aggregations of isolated DNA fragments (“enriched regions”) versus all the other regions (“background”). However, many confounding factors may influence DAE-seq signals. In addition, the signals in adjacent genomic regions may exhibit strong correlations, which invalidate the independence assumption employed by many existing methods. To mitigate these issues, we develop a novel Autoregressive Hidden Markov Model (AR-HMM) to account for covariates effects and violations of the independence assumption. We demonstrate that our AR-HMM leads to improved performance in identifying enriched regions in both simulated and real datasets, especially in those in epigenetic datasets with broader regions of DAE-seq signal enrichment. We also introduce a variable selection procedure in the context of the HMM/AR-HMM where the observations are not independent and the mean value of each state-specific emission distribution is modeled by some covariates. We study the theoretical properties of this variable selection procedure and demonstrate its efficacy in simulated and real DAE-seq data. In summary, we develop several practical approaches for DAE-seq data analysis that are also applicable to more general problems in statistics. PMID:24678134

  12. Renal electrolyte circadian rhythms - Independence from feeding and activity patterns

    NASA Technical Reports Server (NTRS)

    Moore-Ede, M. C.; Herd, J. A.

    1977-01-01

    Experiments were conducted on six unanesthetized chair-acclimatized adult male squirrel monkeys (Saimiri sciureus) weighing 600-900 g to determine whether internal synchronization is the result of simple passive dependence of renal excretory rhythms on endogenous rhythms of those variable that influence electrolyte excretion such as dietary intake and muscular activity. Independence of the urinary rhythms from diurnal variations in feeding, drinking, and activity was secured by depriving the animals of food, water, and training them to perform a two-hourly schedule of feeding, drinking, and activity throughout day and night. Results indicate that the internal synchronization which is normally observed between the behavioral and urinary rhythms cannot be explained by any direct dependence of renal function on behavioral patterns. The most probable mechanism for circadian internal synchronization is that the various behavioral and renal rhythms are controlled by potentially independent separate oscillators which are normally kept in synchrony with one another.

  13. A discrete geometric approach to solving time independent Schroedinger equation

    SciTech Connect

    Specogna, Ruben; Trevisan, Francesco

    2011-02-20

    The time independent Schroedinger equation stems from quantum theory axioms as a partial differential equation. This work aims at providing a novel discrete geometric formulation of this equation in terms of integral variables associated with precise geometric elements of a pair of three-dimensional interlocked grids, one of them based on tetrahedra. We will deduce, in a purely geometric way, a computationally efficient discrete counterpart of the time independent Schroedinger equation in terms of a standard symmetric eigenvalue problem. Moreover boundary and interface conditions together with non homogeneity and anisotropy of the media involved are accounted for in a straightforward manner. This approach yields to a sensible computational advantage with respect to the finite element method, where a generalized eigenvalue problem has to be solved instead. Such a modeling tool can be used for analyzing a number of quantum phenomena in modern nano-structured devices, where the accounting of the real 3D geometry is a crucial issue.

  14. Intra-Individual Variability of Surface Electromyography in Front Crawl Swimming.

    PubMed

    Martens, Jonas; Daly, Daniel; Deschamps, Kevin; Fernandes, Ricardo Jorge Pinto; Staes, Filip

    2015-01-01

    The variability of electromyographic (EMG) recordings between and within participants is a complex problem, rarely studied in swimming. The importance of signal normalization has long been recognized, but the method used might influence variability. The aims of this study were to: (i) assess the intra-individual variability of the EMG signal in highly skilled front crawl swimmers, (ii) determine the influence of two methods of both amplitude and time normalization of the EMG signal on intra-individual variability and of time normalization on muscle activity level and (iii) describe the muscle activity, normalized using MVIC, in relation to upper limb crawl stroke movements. Muscle activity of rectus abdominis and deltoideus medialis was recorded using wireless surface EMG in 15 adult male competitive swimmers during three trials of 12.5 m front crawl at maximal speed without breathing. Two full upper limb cycles were analyzed from each of the swimming trials, resulting in six full cycles used for the intra-individual variability assessment, quantified with the coefficient of variation (CV), coefficient of quartile variation (CQV) and the variance ratio (VR). The results of this study support previous findings on EMG patterns of deltoideus medialis and rectus abdominis as prime mover during the recovery (45% activity relative to MVIC), and stabilizer of the trunk during the pull (14.5% activity) respectively. The intra-individual variability was lower (VR of 0.34-0.47) when compared to other cyclic movements. No meaningful differences were found between variability measures CV or VR when applying either of the amplitude or the time normalization methods. In addition to reporting the mean amplitude and standard deviation, future EMG studies in swimming should also report the intra-individual variability, preferably using VR as it is independent of peak amplitude, provides a good measure of repeatability and is insensitive to mean EMG amplitude and the degree of

  15. Intra-Individual Variability of Surface Electromyography in Front Crawl Swimming.

    PubMed

    Martens, Jonas; Daly, Daniel; Deschamps, Kevin; Fernandes, Ricardo Jorge Pinto; Staes, Filip

    2015-01-01

    The variability of electromyographic (EMG) recordings between and within participants is a complex problem, rarely studied in swimming. The importance of signal normalization has long been recognized, but the method used might influence variability. The aims of this study were to: (i) assess the intra-individual variability of the EMG signal in highly skilled front crawl swimmers, (ii) determine the influence of two methods of both amplitude and time normalization of the EMG signal on intra-individual variability and of time normalization on muscle activity level and (iii) describe the muscle activity, normalized using MVIC, in relation to upper limb crawl stroke movements. Muscle activity of rectus abdominis and deltoideus medialis was recorded using wireless surface EMG in 15 adult male competitive swimmers during three trials of 12.5 m front crawl at maximal speed without breathing. Two full upper limb cycles were analyzed from each of the swimming trials, resulting in six full cycles used for the intra-individual variability assessment, quantified with the coefficient of variation (CV), coefficient of quartile variation (CQV) and the variance ratio (VR). The results of this study support previous findings on EMG patterns of deltoideus medialis and rectus abdominis as prime mover during the recovery (45% activity relative to MVIC), and stabilizer of the trunk during the pull (14.5% activity) respectively. The intra-individual variability was lower (VR of 0.34-0.47) when compared to other cyclic movements. No meaningful differences were found between variability measures CV or VR when applying either of the amplitude or the time normalization methods. In addition to reporting the mean amplitude and standard deviation, future EMG studies in swimming should also report the intra-individual variability, preferably using VR as it is independent of peak amplitude, provides a good measure of repeatability and is insensitive to mean EMG amplitude and the degree of

  16. Intra-Individual Variability of Surface Electromyography in Front Crawl Swimming

    PubMed Central

    Martens, Jonas; Daly, Daniel; Deschamps, Kevin; Fernandes, Ricardo Jorge Pinto; Staes, Filip

    2015-01-01

    The variability of electromyographic (EMG) recordings between and within participants is a complex problem, rarely studied in swimming. The importance of signal normalization has long been recognized, but the method used might influence variability. The aims of this study were to: (i) assess the intra-individual variability of the EMG signal in highly skilled front crawl swimmers, (ii) determine the influence of two methods of both amplitude and time normalization of the EMG signal on intra-individual variability and of time normalization on muscle activity level and (iii) describe the muscle activity, normalized using MVIC, in relation to upper limb crawl stroke movements. Muscle activity of rectus abdominis and deltoideus medialis was recorded using wireless surface EMG in 15 adult male competitive swimmers during three trials of 12.5 m front crawl at maximal speed without breathing. Two full upper limb cycles were analyzed from each of the swimming trials, resulting in six full cycles used for the intra-individual variability assessment, quantified with the coefficient of variation (CV), coefficient of quartile variation (CQV) and the variance ratio (VR). The results of this study support previous findings on EMG patterns of deltoideus medialis and rectus abdominis as prime mover during the recovery (45% activity relative to MVIC), and stabilizer of the trunk during the pull (14.5% activity) respectively. The intra-individual variability was lower (VR of 0.34–0.47) when compared to other cyclic movements. No meaningful differences were found between variability measures CV or VR when applying either of the amplitude or the time normalization methods. In addition to reporting the mean amplitude and standard deviation, future EMG studies in swimming should also report the intra-individual variability, preferably using VR as it is independent of peak amplitude, provides a good measure of repeatability and is insensitive to mean EMG amplitude and the degree of

  17. Selection of Momentum Variables for a Three-Dimensional Variational Analysis

    NASA Astrophysics Data System (ADS)

    Xie, Yuanfu; MacDonald, Alexander E.

    2012-03-01

    Three choices of control variables for meteorological variational analysis (3DVAR or 4DVAR) are associated with horizontal wind: (1) streamfunction and velocity potential, (2) eastward and northward velocity, and (3) vorticity and divergence. This study shows theoretical and numerical differences of these variables in practical 3DVAR data assimilation through statistical analysis and numerical experiments. This paper demonstrates that (a) streamfunction and velocity potential could potentially introduce analysis errors; (b) A 3DVAR using velocity or vorticity and divergence provides a natural scale dependent influence radius in addition to the covariance; (c) for a regional analysis, streamfunction and velocity potential are retrieved from the background velocity field with Neumann boundary condition. Improper boundary conditions could result in further analysis errors; (d) a variational data assimilation or an inverse problem using derivatives as control variables yields smoother analyses, for example, a 3DVAR using vorticity and divergence as controls yields smoother wind analyses than those analyses obtained by a 3DVAR using either velocity or streamfunction/velocity potential as control variables; and (e) statistical errors of higher order derivatives of variables are more independent, e.g., the statistical correlation between U and V is smaller than the one between streamfunction and velocity potential, and thus the variables in higher derivatives are more appropriate for a variational system when a cross-correlation between variables is neglected for efficiency or other reasons. In summary, eastward and northward velocity, or vorticity and divergence are preferable control variables for variational systems and the former is more attractive because of its numerical efficiency. Numerical experiments are presented using analytic functions and real atmospheric observations.

  18. [The research protocol IV: study variables].

    PubMed

    Villasís-Keever, Miguel Ángel; Miranda-Novales, María Guadalupe

    2016-01-01

    The variables in a research study are all that is measured, the information collected, or the data that is collected in order to answer the research questions, which are specified in the objectives. Their selection is essential to the research protocol. This article aims to point out the elements to be considered in the section of the variables. To avoid ambiguity, it is necessary to select only those that will help achieve the study objectives. It should subsequently be defined how they will be measured to ensure that the findings can be replicated; it is therefore desirable to include conceptual and operational definitions. From the methodological point of view, the classification of variables helps us understand how the relationship between them is conceptualized. Depending on the study design, the independent, dependent, universal, and confounding variables should be noted. Another indispensable element for planning statistical analyses is the scale of variable measurement. Therefore, one must specify whether the variables correspond to one of the following four: qualitative nominal, qualitative ordinal, quantitative range, or quantitative ratio. Finally, we should detail the measurement units of each variable. PMID:27560918

  19. [The research protocol IV: study variables].

    PubMed

    Villasís-Keever, Miguel Ángel; Miranda-Novales, María Guadalupe

    2016-01-01

    The variables in a research study are all that is measured, the information collected, or the data that is collected in order to answer the research questions, which are specified in the objectives. Their selection is essential to the research protocol. This article aims to point out the elements to be considered in the section of the variables. To avoid ambiguity, it is necessary to select only those that will help achieve the study objectives. It should subsequently be defined how they will be measured to ensure that the findings can be replicated; it is therefore desirable to include conceptual and operational definitions. From the methodological point of view, the classification of variables helps us understand how the relationship between them is conceptualized. Depending on the study design, the independent, dependent, universal, and confounding variables should be noted. Another indispensable element for planning statistical analyses is the scale of variable measurement. Therefore, one must specify whether the variables correspond to one of the following four: qualitative nominal, qualitative ordinal, quantitative range, or quantitative ratio. Finally, we should detail the measurement units of each variable.

  20. Understanding Brown Dwarf Variability

    NASA Technical Reports Server (NTRS)

    Marley, Mark S.

    2013-01-01

    Surveys of brown dwarf variability continue to find that roughly half of all brown dwarfs are variable. While variability is observed amongst all types of brown dwarfs, amplitudes are typically greatest for L-T transition objects. In my talk I will discuss the possible physical mechanisms that are responsible for the observed variability. I will particularly focus on comparing and contrasting the effects of changes in atmospheric thermal profile and cloud opacity. The two different mechanisms will produce different variability signatures and I will discuss the extent to which the current datasets constrain both mechanisms. By combining constraints from studies of variability with existing spectral and photometric datasets we can begin to construct and test self-consistent models of brown dwarf atmospheres. These models not only aid in the interpretation of existing objects but also inform studies of directly imaged giant planets.

  1. Enantioselective Michael Addition of Water

    PubMed Central

    Chen, Bi-Shuang; Resch, Verena; Otten, Linda G; Hanefeld, Ulf

    2015-01-01

    The enantioselective Michael addition using water as both nucleophile and solvent has to date proved beyond the ability of synthetic chemists. Herein, the direct, enantioselective Michael addition of water in water to prepare important β-hydroxy carbonyl compounds using whole cells of Rhodococcus strains is described. Good yields and excellent enantioselectivities were achieved with this method. Deuterium labeling studies demonstrate that a Michael hydratase catalyzes the water addition exclusively with anti-stereochemistry. PMID:25529526

  2. Enantioselective Michael addition of water.

    PubMed

    Chen, Bi-Shuang; Resch, Verena; Otten, Linda G; Hanefeld, Ulf

    2015-02-01

    The enantioselective Michael addition using water as both nucleophile and solvent has to date proved beyond the ability of synthetic chemists. Herein, the direct, enantioselective Michael addition of water in water to prepare important β-hydroxy carbonyl compounds using whole cells of Rhodococcus strains is described. Good yields and excellent enantioselectivities were achieved with this method. Deuterium labeling studies demonstrate that a Michael hydratase catalyzes the water addition exclusively with anti-stereochemistry.

  3. Bayesian Estimation of Conditional Independence Graphs Improves Functional Connectivity Estimates

    PubMed Central

    Hinne, Max; Janssen, Ronald J.; Heskes, Tom; van Gerven, Marcel A.J.

    2015-01-01

    Functional connectivity concerns the correlated activity between neuronal populations in spatially segregated regions of the brain, which may be studied using functional magnetic resonance imaging (fMRI). This coupled activity is conveniently expressed using covariance, but this measure fails to distinguish between direct and indirect effects. A popular alternative that addresses this issue is partial correlation, which regresses out the signal of potentially confounding variables, resulting in a measure that reveals only direct connections. Importantly, provided the data are normally distributed, if two variables are conditionally independent given all other variables, their respective partial correlation is zero. In this paper, we propose a probabilistic generative model that allows us to estimate functional connectivity in terms of both partial correlations and a graph representing conditional independencies. Simulation results show that this methodology is able to outperform the graphical LASSO, which is the de facto standard for estimating partial correlations. Furthermore, we apply the model to estimate functional connectivity for twenty subjects using resting-state fMRI data. Results show that our model provides a richer representation of functional connectivity as compared to considering partial correlations alone. Finally, we demonstrate how our approach can be extended in several ways, for instance to achieve data fusion by informing the conditional independence graph with data from probabilistic tractography. As our Bayesian formulation of functional connectivity provides access to the posterior distribution instead of only to point estimates, we are able to quantify the uncertainty associated with our results. This reveals that while we are able to infer a clear backbone of connectivity in our empirical results, the data are not accurately described by simply looking at the mode of the distribution over connectivity. The implication of this is that

  4. Independent evolution of four heme peroxidase superfamilies.

    PubMed

    Zámocký, Marcel; Hofbauer, Stefan; Schaffner, Irene; Gasselhuber, Bernhard; Nicolussi, Andrea; Soudi, Monika; Pirker, Katharina F; Furtmüller, Paul G; Obinger, Christian

    2015-05-15

    Four heme peroxidase superfamilies (peroxidase-catalase, peroxidase-cyclooxygenase, peroxidase-chlorite dismutase and peroxidase-peroxygenase superfamily) arose independently during evolution, which differ in overall fold, active site architecture and enzymatic activities. The redox cofactor is heme b or posttranslationally modified heme that is ligated by either histidine or cysteine. Heme peroxidases are found in all kingdoms of life and typically catalyze the one- and two-electron oxidation of a myriad of organic and inorganic substrates. In addition to this peroxidatic activity distinct (sub)families show pronounced catalase, cyclooxygenase, chlorite dismutase or peroxygenase activities. Here we describe the phylogeny of these four superfamilies and present the most important sequence signatures and active site architectures. The classification of families is described as well as important turning points in evolution. We show that at least three heme peroxidase superfamilies have ancient prokaryotic roots with several alternative ways of divergent evolution. In later evolutionary steps, they almost always produced highly evolved and specialized clades of peroxidases in eukaryotic kingdoms with a significant portion of such genes involved in coding various fusion proteins with novel physiological functions.

  5. Hybrid Scheduling Model for Independent Grid Tasks

    PubMed Central

    Shanthini, J.; Kalaikumaran, T.; Karthik, S.

    2015-01-01

    Grid computing facilitates the resource sharing through the administrative domains which are geographically distributed. Scheduling in a distributed heterogeneous environment is intrinsically very hard because of the heterogeneous nature of resource collection. Makespan and tardiness are two different measures of scheduling, and many of the previous researches concentrated much on reduction of makespan, which measures the machine utilization. In this paper, we propose a hybrid scheduling algorithm for scheduling independent grid tasks with the objective of reducing total weighted tardiness of grid tasks. Tardiness is to measure the due date performance, which has a direct impact on cost for executing the jobs. In this paper we propose BG_ATC algorithm which is a combination of best gap (BG) search and Apparent Tardiness Cost (ATC) indexing algorithm. Furthermore, we implemented these two algorithms in two different phases of the scheduling process. In addition to that, the comparison was made on results with various benchmark algorithms and the experimental results show that our algorithm outperforms the benchmark algorithms. PMID:26543897

  6. Hybrid Scheduling Model for Independent Grid Tasks.

    PubMed

    Shanthini, J; Kalaikumaran, T; Karthik, S

    2015-01-01

    Grid computing facilitates the resource sharing through the administrative domains which are geographically distributed. Scheduling in a distributed heterogeneous environment is intrinsically very hard because of the heterogeneous nature of resource collection. Makespan and tardiness are two different measures of scheduling, and many of the previous researches concentrated much on reduction of makespan, which measures the machine utilization. In this paper, we propose a hybrid scheduling algorithm for scheduling independent grid tasks with the objective of reducing total weighted tardiness of grid tasks. Tardiness is to measure the due date performance, which has a direct impact on cost for executing the jobs. In this paper we propose BG_ATC algorithm which is a combination of best gap (BG) search and Apparent Tardiness Cost (ATC) indexing algorithm. Furthermore, we implemented these two algorithms in two different phases of the scheduling process. In addition to that, the comparison was made on results with various benchmark algorithms and the experimental results show that our algorithm outperforms the benchmark algorithms. PMID:26543897

  7. Hybrid Scheduling Model for Independent Grid Tasks.

    PubMed

    Shanthini, J; Kalaikumaran, T; Karthik, S

    2015-01-01

    Grid computing facilitates the resource sharing through the administrative domains which are geographically distributed. Scheduling in a distributed heterogeneous environment is intrinsically very hard because of the heterogeneous nature of resource collection. Makespan and tardiness are two different measures of scheduling, and many of the previous researches concentrated much on reduction of makespan, which measures the machine utilization. In this paper, we propose a hybrid scheduling algorithm for scheduling independent grid tasks with the objective of reducing total weighted tardiness of grid tasks. Tardiness is to measure the due date performance, which has a direct impact on cost for executing the jobs. In this paper we propose BG_ATC algorithm which is a combination of best gap (BG) search and Apparent Tardiness Cost (ATC) indexing algorithm. Furthermore, we implemented these two algorithms in two different phases of the scheduling process. In addition to that, the comparison was made on results with various benchmark algorithms and the experimental results show that our algorithm outperforms the benchmark algorithms.

  8. Likelihood-based population independent component analysis

    PubMed Central

    Eloyan, Ani; Crainiceanu, Ciprian M.; Caffo, Brian S.

    2013-01-01

    Independent component analysis (ICA) is a widely used technique for blind source separation, used heavily in several scientific research areas including acoustics, electrophysiology, and functional neuroimaging. We propose a scalable two-stage iterative true group ICA methodology for analyzing population level functional magnetic resonance imaging (fMRI) data where the number of subjects is very large. The method is based on likelihood estimators of the underlying source densities and the mixing matrix. As opposed to many commonly used group ICA algorithms, the proposed method does not require significant data reduction by a 2-fold singular value decomposition. In addition, the method can be applied to a large group of subjects since the memory requirements are not restrictive. The performance of our approach is compared with a commonly used group ICA algorithm via simulation studies. Furthermore, the proposed method is applied to a large collection of resting state fMRI datasets. The results show that established brain networks are well recovered by the proposed algorithm. PMID:23314416

  9. Protein Conformational Entropy is Independent of Solvent

    NASA Astrophysics Data System (ADS)

    Nucci, Nathaniel; Moorman, Veronica; Gledhill, John; Valentine, Kathleen; Wand, A. Joshua

    Proteins exhibit most of their conformational entropy in individual bond vector motions on the ps-ns timescale. These motions can be examined through determination of the Lipari-Szabo generalized squared order parameter (O2) using NMR spin relaxation measurements. It is often argued that most protein motions are intimately dependent on the nature of the solvating environment. Here the solvent dependence of the fast protein dynamics is directly assessed. Using the model protein ubiquitin, the order parameters of the backbone and methyl groups are shown to be generally unaffected by up to a six-fold increase in bulk viscosity or by encapsulation in the nanoscale interior of a reverse micelle. In addition, the reverse micelle condition permits direct comparison of protein dynamics to the mobility of the hydration layer; no correlation is observed. The dynamics of aromatic side chains are also assessed and provide an estimate of the length- and timescale of protein motions where solvent dependence is seen. These data demonstrate the solvent independence of conformational entropy, clarifying a long-held misconception in the fundamental behavior of biological macromolecules. Supported by the National Science Foundation.

  10. Source-Independent Quantum Random Number Generation

    NASA Astrophysics Data System (ADS)

    Cao, Zhu; Zhou, Hongyi; Yuan, Xiao; Ma, Xiongfeng

    2016-01-01

    Quantum random number generators can provide genuine randomness by appealing to the fundamental principles of quantum mechanics. In general, a physical generator contains two parts—a randomness source and its readout. The source is essential to the quality of the resulting random numbers; hence, it needs to be carefully calibrated and modeled to achieve information-theoretical provable randomness. However, in practice, the source is a complicated physical system, such as a light source or an atomic ensemble, and any deviations in the real-life implementation from the theoretical model may affect the randomness of the output. To close this gap, we propose a source-independent scheme for quantum random number generation in which output randomness can be certified, even when the source is uncharacterized and untrusted. In our randomness analysis, we make no assumptions about the dimension of the source. For instance, multiphoton emissions are allowed in optical implementations. Our analysis takes into account the finite-key effect with the composable security definition. In the limit of large data size, the length of the input random seed is exponentially small compared to that of the output random bit. In addition, by modifying a quantum key distribution system, we experimentally demonstrate our scheme and achieve a randomness generation rate of over 5 ×103 bit /s .

  11. Halo-independent direct detection analyses without mass assumptions

    SciTech Connect

    Anderson, Adam J.; Fox, Patrick J.; Kahn, Yonatan; McCullough, Matthew

    2015-10-06

    Results from direct detection experiments are typically interpreted by employing an assumption about the dark matter velocity distribution, with results presented in the m{sub χ}−σ{sub n} plane. Recently methods which are independent of the DM halo velocity distribution have been developed which present results in the v{sub min}−g-tilde plane, but these in turn require an assumption on the dark matter mass. Here we present an extension of these halo-independent methods for dark matter direct detection which does not require a fiducial choice of the dark matter mass. With a change of variables from v{sub min} to nuclear recoil momentum (p{sub R}), the full halo-independent content of an experimental result for any dark matter mass can be condensed into a single plot as a function of a new halo integral variable, which we call h-til-tilde(p{sub R}). The entire family of conventional halo-independent g-tilde(v{sub min}) plots for all DM masses are directly found from the single h-tilde(p{sub R}) plot through a simple rescaling of axes. By considering results in h-tilde(p{sub R}) space, one can determine if two experiments are inconsistent for all masses and all physically possible halos, or for what range of dark matter masses the results are inconsistent for all halos, without the necessity of multiple g-tilde(v{sub min}) plots for different DM masses. We conduct a sample analysis comparing the CDMS II Si events to the null results from LUX, XENON10, and SuperCDMS using our method and discuss how the results can be strengthened by imposing the physically reasonable requirement of a finite halo escape velocity.

  12. Halo-independent direct detection analyses without mass assumptions

    DOE PAGES

    Anderson, Adam J.; Fox, Patrick J.; Kahn, Yonatan; McCullough, Matthew

    2015-10-06

    Results from direct detection experiments are typically interpreted by employing an assumption about the dark matter velocity distribution, with results presented in the mχ – σn plane. Recently methods which are independent of the DM halo velocity distribution have been developed which present results in the vmin – g~ plane, but these in turn require an assumption on the dark matter mass. Here we present an extension of these halo-independent methods for dark matter direct detection which does not require a fiducial choice of the dark matter mass. With a change of variables from vmin to nuclear recoil momentum (pR),more » the full halo-independent content of an experimental result for any dark matter mass can be condensed into a single plot as a function of a new halo integral variable, which we call tilde h(pR). The entire family of conventional halo-independent tilde g~(vmin) plots for all DM masses are directly found from the single tilde h~(pR) plot through a simple rescaling of axes. By considering results in tildeh~(pR) space, one can determine if two experiments are inconsistent for all masses and all physically possible halos, or for what range of dark matter masses the results are inconsistent for all halos, without the necessity of multiple tilde g~(vmin) plots for different DM masses. As a result, we conduct a sample analysis comparing the CDMS II Si events to the null results from LUX, XENON10, and SuperCDMS using our method and discuss how the results can be strengthened by imposing the physically reasonable requirement of a finite halo escape velocity.« less

  13. Halo-independent direct detection analyses without mass assumptions

    SciTech Connect

    Anderson, Adam J.; Fox, Patrick J.; Kahn, Yonatan; McCullough, Matthew E-mail: pjfox@fnal.gov E-mail: matthew.mccullough@cern.ch

    2015-10-01

    Results from direct detection experiments are typically interpreted by employing an assumption about the dark matter velocity distribution, with results presented in the m{sub χ}−σ{sub n} plane. Recently methods which are independent of the DM halo velocity distribution have been developed which present results in the v{sub min}− g-tilde plane, but these in turn require an assumption on the dark matter mass. Here we present an extension of these halo-independent methods for dark matter direct detection which does not require a fiducial choice of the dark matter mass. With a change of variables from v{sub min} to nuclear recoil momentum (p{sub R}), the full halo-independent content of an experimental result for any dark matter mass can be condensed into a single plot as a function of a new halo integral variable, which we call h-tilde (p{sub R}). The entire family of conventional halo-independent g-tilde (v{sub min}) plots for all DM masses are directly found from the single h-tilde (p{sub R}) plot through a simple rescaling of axes. By considering results in h-tilde (p{sub R}) space, one can determine if two experiments are inconsistent for all masses and all physically possible halos, or for what range of dark matter masses the results are inconsistent for all halos, without the necessity of multiple g-tilde (v{sub min}) plots for different DM masses. We conduct a sample analysis comparing the CDMS II Si events to the null results from LUX, XENON10, and SuperCDMS using our method and discuss how the results can be strengthened by imposing the physically reasonable requirement of a finite halo escape velocity.

  14. Halo-independent direct detection analyses without mass assumptions

    SciTech Connect

    Anderson, Adam J.; Fox, Patrick J.; Kahn, Yonatan; McCullough, Matthew

    2015-10-06

    Results from direct detection experiments are typically interpreted by employing an assumption about the dark matter velocity distribution, with results presented in the mχ – σn plane. Recently methods which are independent of the DM halo velocity distribution have been developed which present results in the vmin – g~ plane, but these in turn require an assumption on the dark matter mass. Here we present an extension of these halo-independent methods for dark matter direct detection which does not require a fiducial choice of the dark matter mass. With a change of variables from vmin to nuclear recoil momentum (pR), the full halo-independent content of an experimental result for any dark matter mass can be condensed into a single plot as a function of a new halo integral variable, which we call tilde h(pR). The entire family of conventional halo-independent tilde g~(vmin) plots for all DM masses are directly found from the single tilde h~(pR) plot through a simple rescaling of axes. By considering results in tildeh~(pR) space, one can determine if two experiments are inconsistent for all masses and all physically possible halos, or for what range of dark matter masses the results are inconsistent for all halos, without the necessity of multiple tilde g~(vmin) plots for different DM masses. As a result, we conduct a sample analysis comparing the CDMS II Si events to the null results from LUX, XENON10, and SuperCDMS using our method and discuss how the results can be strengthened by imposing the physically reasonable requirement of a finite halo escape velocity.

  15. What is Optimum Variability?

    PubMed

    Schuldberg, David

    2015-10-01

    Guastello (2015a) opened the call for articles for this issue with Goldberger (1991) and colleagues' findings of chaotic variability in healthy heart rate, noting, 'the principle of healthy variability has extended to other biomedical and psychological phenomena.' He suggests a dialectical underpinning for optimal variability involving 'a combination of the minimum entropy or free energy principle that pushes in a downward direction, and Ashby's Law of Requisite Variety that pushes in an upward direction.' Each of the papers in this issue addresses optimal variability across a variety of health-related areas. The present article surveys these seven papers in relation to five conceptual questions about optimal variability: (a) Is variability a positive or a negative, and how are positive things related to health? (b) How shall we define and measure variability? (c) What constitutes an optimum, and how do we locate one? (d) What is the relationship between optimum variability and health? Finally, it touches on (e) What are underlying principles and phenomena behind healthy variability, and can they inform our vocabulary for health? The paper concludes by discussing practical approaches to dealing with optimization. PMID:26375940

  16. VARIABLE TIME DELAY MEANS

    DOEpatents

    Clemensen, R.E.

    1959-11-01

    An electrically variable time delay line is described which may be readily controlled simuitaneously with variable impedance matching means coupied thereto such that reflections are prevented. Broadly, the delay line includes a signal winding about a magnetic core whose permeability is electrically variable. Inasmuch as the inductance of the line varies directly with the permeability, the time delay and characteristic impedance of the line both vary as the square root of the permeability. Consequently, impedance matching means may be varied similariy and simultaneously w:th the electrically variable permeability to match the line impedance over the entire range of time delay whereby reflections are prevented.

  17. The ROSAT variable sky

    NASA Technical Reports Server (NTRS)

    Angelini, L.; Giommi, P.; White, N. E.

    1996-01-01

    The spectral and timing characteristics from a sample, of 91 objects, of the variable sources obtained using the Kolmogorov-Smirnov test technique are presented. The data were extracted from the catalog constructed by White, Giommi and Angelini, the WGACAT, based on the pointed observations from the Rosat missions. The application of the test revealed more than 2400 individual variable candidates, with 'sq chi' greater than 12. The sample of these variable sources, mostly unidentified, probably contains many flare stars, a few cataclysmic variables and a possible transient source.

  18. Test of independence for generalized Farlie-Gumbel-Morgenstern distributions

    NASA Astrophysics Data System (ADS)

    Guven, Bilgehan; Kotz, Samual

    2008-02-01

    Given a pair of absolutely continuous random variables (X,Y) distributed as the generalized Farlie-Gumbel-Morgenstern (GFGM) distribution, we develop a test for testing the hypothesis: X and Y are independent vs. the alternative; X and Y are positively (negatively) quadrant dependent above a preassigned degree of dependence. The proposed test maximizes the minimum power over the alternative hypothesis. Also it possesses a monotone increasing power with respect to the dependence parameter of the GFGM distribution. An asymptotic distribution of the test statistic and an approximate test power are also studied.

  19. Independent Long Fingers are not Essential for a Grasping Hand

    PubMed Central

    Montagnani, Federico; Controzzi, Marco; Cipriani, Christian

    2016-01-01

    The human hand is a complex integrated system with motor and sensory components that provides individuals with high functionality and elegant behaviour. In direct connection with the brain, the hand is capable of performing countless actions ranging from fine digit manipulation to the handling of heavy objects. However the question of which movements mostly contribute to the manipulation skills of the hand, and thus should be included in prosthetic hands, is yet to be answered. Building from our previous work, and assuming that a hand with independent long fingers allowed performance comparable to a hand with coupled fingers, here we explored the actual contribution of independent fingers while performing activities of daily living using custom built orthoses. Our findings show that, when an opposable thumb is present, independent long fingers provide a measureable advantage in performing activities of daily living only when precision grasps are involved. In addition, the results suggest that the remarkable grasping skills of the human hand rely more on the independent abduction/adduction of the fingers than on their independent flexion/extension. These findings are of interest to the designers of artificial hands, including biomimetic prostheses and exoskeletons. PMID:27759046

  20. Geometry-independent energy band simulator for radially symmetric diodes

    NASA Astrophysics Data System (ADS)

    Kirkpatrick, T.; Buonassisi, T.

    2016-07-01

    In this work, a geometrically independent method to calculate the energy band diagram of radially symmetric diodes is reported. For radially symmetric diodes, the calculation of electron (or hole) energies across the junction can be reduced to a singular spatially dependent variable. Because geometry is not incorporated into the calculation a priori, by reducing the physics to a single spatial variable, energy band calculations can be performed in multiple geometries, simultaneously, for direct comparison to each other. The calculation outlined herein is pseudo-analytical and does not utilize finite element and/or control volume methods. It is, therefore, capable of generating spatially analytic equations for analyzing limiting scenarios of the junction, beneficial for yielding insight into the physics and design criteria of depletion for non-planar semiconducting devices.

  1. Color Addition and Subtraction Apps

    ERIC Educational Resources Information Center

    Ruiz, Frances; Ruiz, Michael J.

    2015-01-01

    Color addition and subtraction apps in HTML5 have been developed for students as an online hands-on experience so that they can more easily master principles introduced through traditional classroom demonstrations. The evolution of the additive RGB color model is traced through the early IBM color adapters so that students can proceed step by step…

  2. Guide to good practices for independent verification

    SciTech Connect

    1998-12-01

    This Guide to Good Practices is written to enhance understanding of, and provide direction for, Independent Verification, Chapter X of Department of Energy (DOE) Order 5480.19, Conduct of Operations Requirements for DOE Facilities. The practices in this guide should be considered when planning or reviewing independent verification activities. Contractors are advised to adopt procedures that meet the intent of DOE Order 5480.19. Independent Verification is an element of an effective Conduct of Operations program. The complexity and array of activities performed in DOE facilities dictate the necessity for coordinated independent verification activities to promote safe and efficient operations.

  3. Printability of alloys for additive manufacturing.

    PubMed

    Mukherjee, T; Zuback, J S; De, A; DebRoy, T

    2016-01-01

    Although additive manufacturing (AM), or three dimensional (3D) printing, provides significant advantages over existing manufacturing techniques, metallic parts produced by AM are susceptible to distortion, lack of fusion defects and compositional changes. Here we show that the printability, or the ability of an alloy to avoid these defects, can be examined by developing and testing appropriate theories. A theoretical scaling analysis is used to test vulnerability of various alloys to thermal distortion. A theoretical kinetic model is used to examine predisposition of different alloys to AM induced compositional changes. A well-tested numerical heat transfer and fluid flow model is used to compare susceptibilities of various alloys to lack of fusion defects. These results are tested and validated with independent experimental data. The findings presented in this paper are aimed at achieving distortion free, compositionally sound and well bonded metallic parts.

  4. Printability of alloys for additive manufacturing

    PubMed Central

    Mukherjee, T.; Zuback, J. S.; De, A.; DebRoy, T.

    2016-01-01

    Although additive manufacturing (AM), or three dimensional (3D) printing, provides significant advantages over existing manufacturing techniques, metallic parts produced by AM are susceptible to distortion, lack of fusion defects and compositional changes. Here we show that the printability, or the ability of an alloy to avoid these defects, can be examined by developing and testing appropriate theories. A theoretical scaling analysis is used to test vulnerability of various alloys to thermal distortion. A theoretical kinetic model is used to examine predisposition of different alloys to AM induced compositional changes. A well-tested numerical heat transfer and fluid flow model is used to compare susceptibilities of various alloys to lack of fusion defects. These results are tested and validated with independent experimental data. The findings presented in this paper are aimed at achieving distortion free, compositionally sound and well bonded metallic parts. PMID:26796864

  5. Printability of alloys for additive manufacturing

    NASA Astrophysics Data System (ADS)

    Mukherjee, T.; Zuback, J. S.; de, A.; Debroy, T.

    2016-01-01

    Although additive manufacturing (AM), or three dimensional (3D) printing, provides significant advantages over existing manufacturing techniques, metallic parts produced by AM are susceptible to distortion, lack of fusion defects and compositional changes. Here we show that the printability, or the ability of an alloy to avoid these defects, can be examined by developing and testing appropriate theories. A theoretical scaling analysis is used to test vulnerability of various alloys to thermal distortion. A theoretical kinetic model is used to examine predisposition of different alloys to AM induced compositional changes. A well-tested numerical heat transfer and fluid flow model is used to compare susceptibilities of various alloys to lack of fusion defects. These results are tested and validated with independent experimental data. The findings presented in this paper are aimed at achieving distortion free, compositionally sound and well bonded metallic parts.

  6. Printability of alloys for additive manufacturing.

    PubMed

    Mukherjee, T; Zuback, J S; De, A; DebRoy, T

    2016-01-01

    Although additive manufacturing (AM), or three dimensional (3D) printing, provides significant advantages over existing manufacturing techniques, metallic parts produced by AM are susceptible to distortion, lack of fusion defects and compositional changes. Here we show that the printability, or the ability of an alloy to avoid these defects, can be examined by developing and testing appropriate theories. A theoretical scaling analysis is used to test vulnerability of various alloys to thermal distortion. A theoretical kinetic model is used to examine predisposition of different alloys to AM induced compositional changes. A well-tested numerical heat transfer and fluid flow model is used to compare susceptibilities of various alloys to lack of fusion defects. These results are tested and validated with independent experimental data. The findings presented in this paper are aimed at achieving distortion free, compositionally sound and well bonded metallic parts. PMID:26796864

  7. Printability of alloys for additive manufacturing

    DOE PAGES

    Mukherjee, T.; Zuback, J. S.; De, A.; DebRoy, T.

    2016-01-22

    Although additive manufacturing (AM), or three dimensional (3D) printing, provides significant advantages over existing manufacturing techniques, metallic parts produced by AM are susceptible to distortion, lack of fusion defects and compositional changes. Here we show that the printability, or the ability of an alloy to avoid these defects, can be examined by developing and testing appropriate theories. A theoretical scaling analysis is used to test vulnerability of various alloys to thermal distortion. A theoretical kinetic model is used to examine predisposition of different alloys to AM induced compositional changes. A well-tested numerical heat transfer and fluid flow model is usedmore » to compare susceptibilities of various alloys to lack of fusion defects. These results are tested and validated with independent experimental data. Here, the findings presented in this paper are aimed at achieving distortion free, compositionally sound and well bonded metallic parts.« less

  8. Young proteins experience more variable selection pressures than old proteins.

    PubMed

    Vishnoi, Anchal; Kryazhimskiy, Sergey; Bazykin, Georgii A; Hannenhalli, Sridhar; Plotkin, Joshua B

    2010-11-01

    It is well known that young proteins tend to experience weaker purifying selection and evolve more quickly than old proteins. Here, we show that, in addition, young proteins tend to experience more variable selection pressures over time than old proteins. We demonstrate this pattern in three independent taxonomic groups: yeast, Drosophila, and mammals. The increased variability of selection pressures on young proteins is highly significant even after controlling for the fact that young proteins are typically shorter and experience weaker purifying selection than old proteins. The majority of our results are consistent with the hypothesis that the function of a young gene tends to change over time more readily than that of an old gene. At the same time, our results may be caused in part by young genes that serve constant functions over time, but nevertheless appear to evolve under changing selection pressures due to depletion of adaptive mutations. In either case, our results imply that the evolution of a protein-coding sequence is partly determined by its age and origin, and not only by the phenotypic properties of the encoded protein. We discuss, via specific examples, the consequences of these findings for understanding of the sources of evolutionary novelty.

  9. RosettaAntibody: antibody variable region homology modeling server.

    PubMed

    Sircar, Aroop; Kim, Eric T; Gray, Jeffrey J

    2009-07-01

    The RosettaAntibody server (http://antibody.graylab.jhu.edu) predicts the structure of an antibody variable region given the amino-acid sequences of the respective light and heavy chains. In an initial stage, the server identifies and displays the most sequence homologous template structures for the light and heavy framework regions and each of the complementarity determining region (CDR) loops. Subsequently, the most homologous templates are assembled into a side-chain optimized crude model, and the server returns a picture and coordinate file. For users requesting a high-resolution model, the server executes the full RosettaAntibody protocol which additionally models the hyper-variable CDR H3 loop. The high-resolution protocol also relieves steric clashes by optimizing the CDR backbone torsion angles and by simultaneously perturbing the relative orientation of the light and heavy chains. RosettaAntibody generates 2000 independent structures, and the server returns pictures, coordinate files, and detailed scoring information for the 10 top-scoring models. The 10 models enable users to use rational judgment in choosing the best model or to use the set as an ensemble for further studies such as docking. The high-resolution models generated by RosettaAntibody have been used for the successful prediction of antibody-antigen complex structures.

  10. A novel variable selection approach that iteratively optimizes variable space using weighted binary matrix sampling.

    PubMed

    Deng, Bai-chuan; Yun, Yong-huan; Liang, Yi-zeng; Yi, Lun-zhao

    2014-10-01

    In this study, a new optimization algorithm called the Variable Iterative Space Shrinkage Approach (VISSA) that is based on the idea of model population analysis (MPA) is proposed for variable selection. Unlike most of the existing optimization methods for variable selection, VISSA statistically evaluates the performance of variable space in each step of optimization. Weighted binary matrix sampling (WBMS) is proposed to generate sub-models that span the variable subspace. Two rules are highlighted during the optimization procedure. First, the variable space shrinks in each step. Second, the new variable space outperforms the previous one. The second rule, which is rarely satisfied in most of the existing methods, is the core of the VISSA strategy. Compared with some promising variable selection methods such as competitive adaptive reweighted sampling (CARS), Monte Carlo uninformative variable elimination (MCUVE) and iteratively retaining informative variables (IRIV), VISSA showed better prediction ability for the calibration of NIR data. In addition, VISSA is user-friendly; only a few insensitive parameters are needed, and the program terminates automatically without any additional conditions. The Matlab codes for implementing VISSA are freely available on the website: https://sourceforge.net/projects/multivariateanalysis/files/VISSA/.

  11. The WFCAM multiwavelength Variable Star Catalog

    NASA Astrophysics Data System (ADS)

    Ferreira Lopes, C. E.; Dékány, I.; Catelan, M.; Cross, N. J. G.; Angeloni, R.; Leão, I. C.; De Medeiros, J. R.

    2015-01-01

    Context. Stellar variability in the near-infrared (NIR) remains largely unexplored. The exploitation of public science archives with data-mining methods offers a perspective for a time-domain exploration of the NIR sky. Aims: We perform a comprehensive search for stellar variability using the optical-NIR multiband photometric data in the public Calibration Database of the WFCAM Science Archive (WSA), with the aim of contributing to the general census of variable stars and of extending the current scarce inventory of accurate NIR light curves for a number of variable star classes. Methods: Standard data-mining methods were applied to extract and fine-tune time-series data from the WSA. We introduced new variability indices designed for multiband data with correlated sampling, and applied them for preselecting variable star candidates, i.e., light curves that are dominated by correlated variations, from noise-dominated ones. Preselection criteria were established by robust numerical tests for evaluating the response of variability indices to the colored noise characteristic of the data. We performed a period search using the string-length minimization method on an initial catalog of 6551 variable star candidates preselected by variability indices. Further frequency analysis was performed on positive candidates using three additional methods in combination, in order to cope with aliasing. Results: We find 275 periodic variable stars and an additional 44 objects with suspected variability with uncertain periods or apparently aperiodic variation. Only 44 of these objects had been previously known, including 11 RR Lyrae stars on the outskirts of the globular cluster M 3 (NGC 5272). We provide a preliminary classification of the new variable stars that have well-measured light curves, but the variability types of a large number of objects remain ambiguous. We classify most of the new variables as contact binary stars, but we also find several pulsating stars, among which

  12. A variety of variables.

    PubMed

    Jupiter, Daniel C

    2014-01-01

    In designing studies and developing plans for analyses, we must consider which tests are appropriate for the types of variables we are using. Here I describe the types of variables available to us, and I briefly consider the appropriate tools to use in their analysis.

  13. Variable Density Tunnel

    NASA Technical Reports Server (NTRS)

    1931-01-01

    Variable Density Tunnel in operation. Man at far right is probably Harold J. 'Cannonball' Tuner, longtime safety officer, who started with Curtiss in the teens. This view of the Variable Density Tunnel clearly shows the layout of the Tunnel's surroundings, as well as the plumbing and power needs of the this innovative research tool.

  14. Variable Synthetic Capacitance

    NASA Technical Reports Server (NTRS)

    Kleinberg, L. L.

    1986-01-01

    Feedback amplifier circuit synthesizes electronically variable capacitance. Variable Synthetic Capacitor is amplifier circuit with follower/feedback configuration. Effective input capacitance depends on input set current. If synthetic capacitor is connected across resonant element of oscillator, oscillator frequency controlled via input set current. Circuit especially suitable for fine frequency adjustments of piezoelectric-crystal or inductor/capacitor resonant oscillators.

  15. Latent Variable Interaction Modeling.

    ERIC Educational Resources Information Center

    Schumacker, Randall E.

    2002-01-01

    Used simulation to study two different approaches to latent variable interaction modeling with continuous observed variables: (1) a LISREL 8.30 program and (2) data analysis through PRELIS2 and SIMPLIS programs. Results show that parameter estimation was similar but standard errors were different. Discusses differences in ease of implementation.…

  16. Reinforcing Saccadic Amplitude Variability

    ERIC Educational Resources Information Center

    Paeye, Celine; Madelain, Laurent

    2011-01-01

    Saccadic endpoint variability is often viewed as the outcome of neural noise occurring during sensorimotor processing. However, part of this variability might result from operant learning. We tested this hypothesis by reinforcing dispersions of saccadic amplitude distributions, while maintaining constant their medians. In a first experiment we…

  17. Multiple deficits in ADHD: executive dysfunction, delay aversion, reaction time variability, and emotional deficits

    PubMed Central

    Sjöwall, Douglas; Roth, Linda; Lindqvist, Sofia; Thorell, Lisa B

    2013-01-01

    Background The notion that ADHD constitutes a heterogeneous disorder is well accepted. However, this study contributes with new important knowledge by examining independent effects of a large range of neuropsychological deficits. In addition, the study investigated whether deficits in emotional functioning constitute a dissociable component of ADHD. Method The study included children with ADHD (n = 102; 7–13 years) and a control sample individually matched with regard to age and gender. The administered tasks were designed to tap into three different neuropsychological domains: executive functions (i.e., working memory, inhibition, and shifting), delay aversion, and reaction time variability. Parent ratings of emotion regulation and a test of emotion recognition were also included. Results Children with ADHD differed significantly from controls on all measures, except for delay aversion and recognition of disgust. No main effects of gender or interaction effects of gender and group were found. More importantly, executive functioning, reaction time variability, and emotional functioning all contributed independently to distinguishing between children with ADHD and controls. Conclusions The current study supports the view of ADHD as a heterogeneous disorder related to multiple neuropsychological deficits. In addition, emotional functioning appears to be an area of importance for ADHD that needs to be incorporated into future theoretical models. PMID:23061803

  18. 5. March 1960 ROOM IN BASEMENT OF THE ADDITION BUILT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. March 1960 ROOM IN BASEMENT OF THE ADDITION BUILT BY JOHN RUSSELL POPE, SUPPER ROOM, LOOKING NORTH 9I.E. IN THE DIRECTION OF MOUNT VERNON PLACE) - Garrett-Jacobs House, 7, 9, 11, 13 West Mount Vernon Place, Baltimore, Independent City, MD

  19. 9. March 1960 FRONT ROOM OF THE ADDITION BUILT BY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. March 1960 FRONT ROOM OF THE ADDITION BUILT BY JOHN RUSSELL POPE FACING ON MOUNT VERNON PLACE. THIS WAS EITHER A LIBRARY OR A ROOM FOR DISPLAYING TROPHIES OR OBJETS D'ART. THE VIEW IS LOOKING SOUTH, THROUGH A STAIRCASE HALL, TO THE THEATER OR BALLROOM - Garrett-Jacobs House, 7, 9, 11, 13 West Mount Vernon Place, Baltimore, Independent City, MD

  20. Universality of State-Independent Violation of Correlation Inequalities for Noncontextual Theories

    SciTech Connect

    Badziag, Piotr; Bengtsson, Ingemar; Cabello, Adan; Pitowsky, Itamar

    2009-07-31

    We show that the state-independent violation of inequalities for noncontextual hidden variable theories introduced in [Phys. Rev. Lett. 101, 210401 (2008)] is universal, i.e., occurs for any quantum mechanical system in which noncontextuality is meaningful. We describe a method to obtain state-independent violations for any system of dimension d>=3. This universality proves that, according to quantum mechanics, there are no 'classical' states.

  1. Basic properties and variability

    NASA Technical Reports Server (NTRS)

    Querci, Francois R.

    1987-01-01

    Giant and supergiant M, S, and C stars are discussed in this survey of research. Basic properties as determined by spectra, chemical composition, photometry, or variability type are discussed. Space motions and space distributions of cool giants are described. Distribution of these stars in our galaxy and those nearby is discussed. Mira variables in particular are surveyed with emphasis on the following topics: (1) phase lag phenomenon; (2) Mira light curves; (3) variations in color indices; (4) determination of multiple periods; (5) correlations between quantities such as period length, light-curve shape, infrared (IR) excess, and visible and IR color diagram; (6) semiregular (SR) variables and different time scales in SR light variations; (7) irregular variable Lb and Lc stars; (8) different time-scale light variations; (9) hydrogen-deficient carbon (HdC) stars, in particular RCB stars; and (10) irreversible changes and rapid evolution in red variable stars.

  2. Color Addition and Subtraction Apps

    NASA Astrophysics Data System (ADS)

    Ruiz, Frances; Ruiz, Michael J.

    2015-10-01

    Color addition and subtraction apps in HTML5 have been developed for students as an online hands-on experience so that they can more easily master principles introduced through traditional classroom demonstrations. The evolution of the additive RGB color model is traced through the early IBM color adapters so that students can proceed step by step in understanding mathematical representations of RGB color. Finally, color addition and subtraction are presented for the X11 colors from web design to illustrate yet another real-life application of color mixing.

  3. Methods to quantify variable importance: implications for the analysis of noisy ecological data.

    PubMed

    Murray, Kim; Conner, Mary M

    2009-02-01

    Determining the importance of independent variables is of practical relevance to ecologists and managers concerned with allocating limited resources to the management of natural systems. Although techniques that identify explanatory variables having the largest influence on the response variable are needed to design management actions effectively, the use of various indices to evaluate variable importance is poorly understood. Using Monte Carlo simulations, we compared six different indices commonly used to evaluate variable importance; zero-order correlations, partial correlations, semipartial correlations, standardized regression coefficients, Akaike weights, and independent effects. We simulated four scenarios to evaluate the indices under progressively more complex circumstances that included correlation between explanatory variables, as well as a spurious variable that was correlated with other explanatory variables, but not with the dependent variable. No index performed perfectly under all circumstances, but partial correlations and Akaike weights performed poorly in all cases. Zero-order correlations was the only measure that detected the presence of a spurious variable, whereas only independent effects assigned overlap areas correctly once the spurious variable was removed. We therefore recommend using zero-order correlations to eliminate predictor variables with correlations near zero, followed by the use of independent effects to assign overlap areas and rank variable importance.

  4. Interpolation of climate variables and temperature modeling

    NASA Astrophysics Data System (ADS)

    Samanta, Sailesh; Pal, Dilip Kumar; Lohar, Debasish; Pal, Babita

    2012-01-01

    Geographic Information Systems (GIS) and modeling are becoming powerful tools in agricultural research and natural resource management. This study proposes an empirical methodology for modeling and mapping of the monthly and annual air temperature using remote sensing and GIS techniques. The study area is Gangetic West Bengal and its neighborhood in the eastern India, where a number of weather systems occur throughout the year. Gangetic West Bengal is a region of strong heterogeneous surface with several weather disturbances. This paper also examines statistical approaches for interpolating climatic data over large regions, providing different interpolation techniques for climate variables' use in agricultural research. Three interpolation approaches, like inverse distance weighted averaging, thin-plate smoothing splines, and co-kriging are evaluated for 4° × 4° area, covering the eastern part of India. The land use/land cover, soil texture, and digital elevation model are used as the independent variables for temperature modeling. Multiple regression analysis with standard method is used to add dependent variables into regression equation. Prediction of mean temperature for monsoon season is better than winter season. Finally standard deviation errors are evaluated after comparing the predicted temperature and observed temperature of the area. For better improvement, distance from the coastline and seasonal wind pattern are stressed to be included as independent variables.

  5. Blind separation of convolutive sEMG mixtures based on independent vector analysis

    NASA Astrophysics Data System (ADS)

    Wang, Xiaomei; Guo, Yina; Tian, Wenyan

    2015-12-01

    An independent vector analysis (IVA) method base on variable-step gradient algorithm is proposed in this paper. According to the sEMG physiological properties, the IVA model is applied to the frequency-domain separation of convolutive sEMG mixtures to extract motor unit action potentials information of sEMG signals. The decomposition capability of proposed method is compared to the one of independent component analysis (ICA), and experimental results show the variable-step gradient IVA method outperforms ICA in blind separation of convolutive sEMG mixtures.

  6. Teebi hypertelorism syndrome: additional cases.

    PubMed

    Machado-Paula, Ligiane Alves; Guion-Almeida, Maria Leine

    2003-03-01

    We report on two unrelated Brazilian boys who have craniofacial and digital anomalies resembling those reported with Teebi hypertelorism syndrome. Additional features such as cleft lip and palate, large uvula, atypical chin and abnormal scapulae were observed.

  7. Independent contractors or employees? Reducing reclassification risks.

    PubMed

    Moore, W B; Groth, C D

    1993-05-01

    With the aggressive stance taken by the IRS regarding worker classification, many organizations may be risking significant retroactive assessments with respect to the use of independent contractors. Employers should be aware of the 20 primary factors considered by the IRS when examining independent contractor relationships and prepare in advance for IRS classification review or audit.

  8. 29 CFR 785.30 - Independent training.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Independent training. 785.30 Section 785.30 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR STATEMENTS OF GENERAL... Lectures, Meetings and Training Programs § 785.30 Independent training. Of course, if an employee on...

  9. Keeping the Learning in Independent Learning

    ERIC Educational Resources Information Center

    Fisher, Douglas; Frey, Nancy

    2013-01-01

    It seems obvious that learning should not stop when independent work begins. In too many cases, however, the tasks and the thinking required to complete independent assignments are limited to regurgitating knowledge. The work itself does not move students' learning forward. Students must master the procedural knowledge (the how) of applying…

  10. Facilitating Engagement by Differentiating Independent Reading

    ERIC Educational Resources Information Center

    Kelley, Michelle J.; Clausen-Grace, Nicki

    2009-01-01

    The authors provide teachers with a rationale for engaging students in independent reading using a differentiated approach. By profiling types of readers, sharing observational tools, and offering teaching suggestions for each type of reader the authors give practical suggestions to facilitate reading engagement and make independent reading more…

  11. 38 CFR 21.76 - Independent living.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) VOCATIONAL REHABILITATION AND EDUCATION Vocational Rehabilitation and Employment Under 38 U.S.C. Chapter 31 Duration of Rehabilitation Programs § 21.76 Independent living. (a) General. A program of independent living services may be authorized to enable the veteran to: (1) Reach the goals of the program, and...

  12. State Policy Toward Independent Postsecondary Institutions.

    ERIC Educational Resources Information Center

    California State Postsecondary Education Commission, Sacramento.

    The statement of state policy toward independent degree-granting colleges and universities in California addresses these issues: independent institutions as a public resource (enrollment, degrees awarded, levels of support, tuition and fees, government revenues, program diversity, and geographic location); state policy toward independent…

  13. 33 CFR 159.93 - Independent supporting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Independent supporting. 159.93 Section 159.93 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.93 Independent supporting....

  14. 32 CFR 169a.16 - Independent review.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 1 2010-07-01 2010-07-01 false Independent review. 169a.16 Section 169a.16 National Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE DEFENSE CONTRACTING COMMERCIAL ACTIVITIES PROGRAM PROCEDURES Procedures § 169a.16 Independent review. (a) The estimates of in-house...

  15. 32 CFR 169a.16 - Independent review.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 1 2011-07-01 2011-07-01 false Independent review. 169a.16 Section 169a.16 National Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE DEFENSE CONTRACTING COMMERCIAL ACTIVITIES PROGRAM PROCEDURES Procedures § 169a.16 Independent review. (a) The estimates of in-house...

  16. Teaching the Declaration of Independence. ERIC Digest.

    ERIC Educational Resources Information Center

    Patrick, John J.

    The Declaration of Independence is the founding document of the United States. It is part of the social studies core curriculum in U.S. schools. By the time they graduate from high school, students are expected to know the main ideas in the Declaration of Independence and their significance. This digest discusses: (1) the origins of the…

  17. Accounting for Independent Schools. Second Edition.

    ERIC Educational Resources Information Center

    National Association of Independent Schools, Boston, MA.

    This is a thoroughly revised edition of the 1969 publication, "Accounting for Independent Schools," a guide that attempted to codify basic accounting principles and practices for specific application to independent schools. The focus of the second edition is more on refining practices than on initiating them, and more on extending the managerial…

  18. Hiring and Retaining Great Independent School Teachers

    ERIC Educational Resources Information Center

    Balossi, Matt; Hernández, Natalie R.

    2016-01-01

    While numerous studies measure teacher effectiveness in public schools, there is little research on teacher quality among independent schools. In fact, the topic of teacher quality in public schools receives widespread media coverage, funding, and special interest. In order to better understand how independent schools describe high-quality…

  19. Teacher's Guide to Independence National Historical Park.

    ERIC Educational Resources Information Center

    National Park Service (Dept. of Interior), Philadelphia, PA. Independence National Historical Park.

    Independence National Historical Park, located in Philadelphia, Pennsylvania, is operated by the National Park Service. The park was authorized by an Act of Congress on June 28, 1948, and formally established on July 4, 1956. The mission of Independence National Historical Park is to preserve its stories, buildings, and artifacts as a source of…

  20. 7 CFR 1217.61 - Independent evaluation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Independent evaluation. 1217.61 Section 1217.61... evaluation. At least once every five years, the Board shall authorize and fund from funds otherwise available to the Board, an independent evaluation of the effectiveness of the Order and the programs...

  1. The Independent Living Behavior Checklist: Experimental Edition.

    ERIC Educational Resources Information Center

    Walls, Richard T.; And Others

    The document describes independent living skills, and provides information on how they can be measured. It is explained in an introductory chapter that the checklist is an extensive list of 343 independent living skill objectives specified in terms of conditions (antecedents or givens), behaviors, and standards. Objectives are classified and…

  2. Polyolefins as additives in plastics

    SciTech Connect

    Deanin, R.D.

    1993-12-31

    Polyolefins are not only major commodity plastics - they are also very useful as additives, both in other polyolefins and also in other types of plastics. This review covers ethylene, propylene, butylene and isobutylene polymers, in blends with each other, and as additives to natural rubber, styrene/butadiene rubber, polystyrene, polyvinyl chloride, polymethyl methacrylate, polyphenylene oxide, polycarbonate, thermoplastic polyesters, polyurethanes, polyamides, and mixed automotive plastics recycling.

  3. Food additives and preschool children.

    PubMed

    Martyn, Danika M; McNulty, Breige A; Nugent, Anne P; Gibney, Michael J

    2013-02-01

    Food additives have been used throughout history to perform specific functions in foods. A comprehensive framework of legislation is in place within Europe to control the use of additives in the food supply and ensure they pose no risk to human health. Further to this, exposure assessments are regularly carried out to monitor population intakes and verify that intakes are not above acceptable levels (acceptable daily intakes). Young children may have a higher dietary exposure to chemicals than adults due to a combination of rapid growth rates and distinct food intake patterns. For this reason, exposure assessments are particularly important in this age group. The paper will review the use of additives and exposure assessment methods and examine factors that affect dietary exposure by young children. One of the most widely investigated unfavourable health effects associated with food additive intake in preschool-aged children are suggested adverse behavioural effects. Research that has examined this relationship has reported a variety of responses, with many noting an increase in hyperactivity as reported by parents but not when assessed using objective examiners. This review has examined the experimental approaches used in such studies and suggests that efforts are needed to standardise objective methods of measuring behaviour in preschool children. Further to this, a more holistic approach to examining food additive intakes by preschool children is advisable, where overall exposure is considered rather than focusing solely on behavioural effects and possibly examining intakes of food additives other than food colours.

  4. Adaptive Variability in Skilled Human Movements

    NASA Astrophysics Data System (ADS)

    Kudo, Kazutoshi; Ohtsuki, Tatsuyuki

    Human movements are produced in variable external/internal environments. Because of this variability, the same motor command can result in quite different movement patterns. Therefore, to produce skilled movements humans must coordinate the variability, not try to exclude it. In addition, because human movements are produced in redundant and complex systems, a combination of variability should be observed in different anatomical/physiological levels. In this paper, we introduce our research about human movement variability that shows remarkable coordination among components, and between organism and environment. We also introduce nonlinear dynamical models that can describe a variety of movements as a self-organization of a dynamical system, because the dynamical systems approach is a major candidate to understand the principle underlying organization of varying systems with huge degrees-of-freedom.

  5. Multi-Time-Scale Variability of Stars

    NASA Astrophysics Data System (ADS)

    Andronov, I. L.

    Physical mechanisms and corresponding mathematical models for different types of stellar variability are reviewed with applications to concrete stars. Special attention is attributed to the following topics: cataclysmic variables (synchronous and synchronizing magnetic systems, non-magnetic novalike stars, dwarf novae; magnetic activity of the red companion, third body around), pulsating variables (additional classification criteria of variability, multiparameter correlation analysis of the characteristics of the mean light curves of groups of long-period stars and of the multi- parameter correlation analysis of the individual characteristics of their pulsations), mathematical models (multi-periodic, multi-harmonic, multi-shift variations with possible trends, mono- and multi- cyclic variations of low coherence and the frequency changing/switching signals, "red noise" variability. Some original papers and links may be found at http://ila.webjump.com

  6. Products of Independent Elliptic Random Matrices

    NASA Astrophysics Data System (ADS)

    O'Rourke, Sean; Renfrew, David; Soshnikov, Alexander; Vu, Van

    2015-07-01

    For fixed , we study the product of independent elliptic random matrices as tends to infinity. Our main result shows that the empirical spectral distribution of the product converges, with probability , to the -th power of the circular law, regardless of the joint distribution of the mirror entries in each matrix. This leads to a new kind of universality phenomenon: the limit law for the product of independent random matrices is independent of the limit laws for the individual matrices themselves. Our result also generalizes earlier results of Götze-Tikhomirov (On the asymptotic spectrum of products of independent random matrices, available at http://arxiv.org/abs/1012.2710) and O'Rourke-Soshnikov (J Probab 16(81):2219-2245, 2011) concerning the product of independent iid random matrices.

  7. Mechanisms and distribution of ion channels in retinal ganglion cells: using temperature as an independent variable.

    PubMed

    Fohlmeister, Jürgen F; Cohen, Ethan D; Newman, Eric A

    2010-03-01

    Trains of action potentials of rat and cat retinal ganglion cells (RGCs) were recorded intracellularly across a temperature range of 7-37 degrees C. Phase plots of the experimental impulse trains were precision fit using multicompartment simulations of anatomically reconstructed rat and cat RGCs. Action potential excitation was simulated with a "Five-channel model" [Na, K(delayed rectifier), Ca, K(A), and K(Ca-activated) channels] and the nonspace-clamped condition of the whole cell recording was exploited to determine the channels' distribution on the dendrites, soma, and proximal axon. At each temperature, optimal phase-plot fits for RGCs occurred with the same unique channel distribution. The "waveform" of the electrotonic current was found to be temperature dependent, which reflected the shape changes in the experimental action potentials and confirmed the channel distributions. The distributions are cell-type specific and adequate for soma and dendritic excitation with a safety margin. The highest Na-channel density was found on an axonal segment some 50-130 microm distal to the soma, as determined from the temperature-dependent "initial segment-somadendritic (IS-SD) break." The voltage dependence of the gating rate constants remains invariant between 7 and 23 degrees C and between 30 and 37 degrees C, but undergoes a transition between 23 and 30 degrees C. Both gating-kinetic and ion-permeability Q10s remain virtually constant between 23 and 37 degrees C (kinetic Q10s = 1.9-1.95; permeability Q10s = 1.49-1.64). The Q10s systematically increase for T <23 degrees C (kinetic Q10 = 8 at T = 8 degrees C). The Na channels were consistently "sleepy" (non-Arrhenius) for T <8 degrees C, with a loss of spiking for T <7 degrees C.

  8. Scale-specific and scale-independent measures of heart rate variability as risk indicators

    NASA Astrophysics Data System (ADS)

    Ashkenazy, Y.; Lewkowicz, M.; Levitan, J.; Havlin, S.; Saermark, K.; Moelgaard, H.; Bloch Thomsen, P. E.; Moller, M.; Hintze, U.; Huikuri, H. V.

    2001-03-01

    We study the correlation properties of heartbeat fluctuations using scale-specific variance (root-mean-square fluctuation) and scaling (correlation) exponents as measures of healthy and cardiac impaired individuals. Our results show that the variance and the scaling exponent are uncorrelated. We find that the variance measure at certain scales is well suited to separate healthy subjects from heart patients. However, for mortality prediction the scaling exponents outperform the variance measure. Our study is based on a database containing recordings from 428 individuals after myocardial infarct (MI) and on a database containing 105 healthy subjects and 11 heart patients. The results have been obtained by applying two recently developed methods (DFA -Detrended Fluctuation Analysis and WAV -Multiresolution Wavelet Analysis) which are shown to be highly correlated.

  9. Mechanisms and Distribution of Ion Channels in Retinal Ganglion Cells: Using Temperature as an Independent Variable

    PubMed Central

    Cohen, Ethan D.; Newman, Eric A.

    2010-01-01

    Trains of action potentials of rat and cat retinal ganglion cells (RGCs) were recorded intracellularly across a temperature range of 7–37°C. Phase plots of the experimental impulse trains were precision fit using multicompartment simulations of anatomically reconstructed rat and cat RGCs. Action potential excitation was simulated with a “Five-channel model” [Na, K(delayed rectifier), Ca, K(A), and K(Ca-activated) channels] and the nonspace-clamped condition of the whole cell recording was exploited to determine the channels' distribution on the dendrites, soma, and proximal axon. At each temperature, optimal phase-plot fits for RGCs occurred with the same unique channel distribution. The “waveform” of the electrotonic current was found to be temperature dependent, which reflected the shape changes in the experimental action potentials and confirmed the channel distributions. The distributions are cell-type specific and adequate for soma and dendritic excitation with a safety margin. The highest Na-channel density was found on an axonal segment some 50–130 μm distal to the soma, as determined from the temperature-dependent “initial segment–somadendritic (IS-SD) break.” The voltage dependence of the gating rate constants remains invariant between 7 and 23°C and between 30 and 37°C, but undergoes a transition between 23 and 30°C. Both gating-kinetic and ion-permeability Q10s remain virtually constant between 23 and 37°C (kinetic Q10s = 1.9–1.95; permeability Q10s = 1.49–1.64). The Q10s systematically increase for T <23°C (kinetic Q10 = 8 at T = 8°C). The Na channels were consistently “sleepy” (non-Arrhenius) for T <8°C, with a loss of spiking for T <7°C. PMID:20053849

  10. Improving Students' Understanding of, and Ability to Identify Independent and Dependent Variables

    ERIC Educational Resources Information Center

    Aldrich, Rosalie S.

    2015-01-01

    Students need to have a basic understanding of research methods before obtaining a communication degree in order to become an intelligent consumer of research--someone who is able to read, understand, explain, and critically evaluate communication and other research reported in scholarly journals as well as in the popular press. These skills are…

  11. Combined prediction model of death toll for road traffic accidents based on independent and dependent variables.

    PubMed

    Feng, Zhong-xiang; Lu, Shi-sheng; Zhang, Wei-hua; Zhang, Nan-nan

    2014-01-01

    In order to build a combined model which can meet the variation rule of death toll data for road traffic accidents and can reflect the influence of multiple factors on traffic accidents and improve prediction accuracy for accidents, the Verhulst model was built based on the number of death tolls for road traffic accidents in China from 2002 to 2011; and car ownership, population, GDP, highway freight volume, highway passenger transportation volume, and highway mileage were chosen as the factors to build the death toll multivariate linear regression model. Then the two models were combined to be a combined prediction model which has weight coefficient. Shapley value method was applied to calculate the weight coefficient by assessing contributions. Finally, the combined model was used to recalculate the number of death tolls from 2002 to 2011, and the combined model was compared with the Verhulst and multivariate linear regression models. The results showed that the new model could not only characterize the death toll data characteristics but also quantify the degree of influence to the death toll by each influencing factor and had high accuracy as well as strong practicability.

  12. Artificial neural network modeling using clinical and knowledge independent variables predicts salt intake reduction behavior

    PubMed Central

    Isma’eel, Hussain A.; Sakr, George E.; Almedawar, Mohamad M.; Fathallah, Jihan; Garabedian, Torkom; Eddine, Savo Bou Zein

    2015-01-01

    Background High dietary salt intake is directly linked to hypertension and cardiovascular diseases (CVDs). Predicting behaviors regarding salt intake habits is vital to guide interventions and increase their effectiveness. We aim to compare the accuracy of an artificial neural network (ANN) based tool that predicts behavior from key knowledge questions along with clinical data in a high cardiovascular risk cohort relative to the least square models (LSM) method. Methods We collected knowledge, attitude and behavior data on 115 patients. A behavior score was calculated to classify patients’ behavior towards reducing salt intake. Accuracy comparison between ANN and regression analysis was calculated using the bootstrap technique with 200 iterations. Results Starting from a 69-item questionnaire, a reduced model was developed and included eight knowledge items found to result in the highest accuracy of 62% CI (58-67%). The best prediction accuracy in the full and reduced models was attained by ANN at 66% and 62%, respectively, compared to full and reduced LSM at 40% and 34%, respectively. The average relative increase in accuracy over all in the full and reduced models is 82% and 102%, respectively. Conclusions Using ANN modeling, we can predict salt reduction behaviors with 66% accuracy. The statistical model has been implemented in an online calculator and can be used in clinics to estimate the patient’s behavior. This will help implementation in future research to further prove clinical utility of this tool to guide therapeutic salt reduction interventions in high cardiovascular risk individuals. PMID:26090333

  13. Combined Prediction Model of Death Toll for Road Traffic Accidents Based on Independent and Dependent Variables

    PubMed Central

    Zhong-xiang, Feng; Shi-sheng, Lu; Wei-hua, Zhang; Nan-nan, Zhang

    2014-01-01

    In order to build a combined model which can meet the variation rule of death toll data for road traffic accidents and can reflect the influence of multiple factors on traffic accidents and improve prediction accuracy for accidents, the Verhulst model was built based on the number of death tolls for road traffic accidents in China from 2002 to 2011; and car ownership, population, GDP, highway freight volume, highway passenger transportation volume, and highway mileage were chosen as the factors to build the death toll multivariate linear regression model. Then the two models were combined to be a combined prediction model which has weight coefficient. Shapley value method was applied to calculate the weight coefficient by assessing contributions. Finally, the combined model was used to recalculate the number of death tolls from 2002 to 2011, and the combined model was compared with the Verhulst and multivariate linear regression models. The results showed that the new model could not only characterize the death toll data characteristics but also quantify the degree of influence to the death toll by each influencing factor and had high accuracy as well as strong practicability. PMID:25610454

  14. Ionospheric variability over Japan

    NASA Astrophysics Data System (ADS)

    Ezquer, R. G.; Mosert, M.; Corbella, R.; Erazu, M.; de La Zerda, L.

    The understanding of ionospheric variability is important for the user of ionospheric models. A satellite designer or operator needs to know not only monthly average conditions but also the expected deviations from these mean values. In order to contribute to the studies on ionospheric variability, in this paper values of critical frequencies of F2, F1 and E regions and M(3000)F2 factor measured at 4 Japanese stations are used. Data correspond to equinoxes, solstices, high and low solar activity. Quartiles and median values are used to specify variability, because they have the advantage of being less affected by large deviations that can occur during magnetic storms. The results are similar for the considered stations and show that the highest variability correspond to foF2. For March high solar activity the variability of fof2 decreases during hours of maximum ionisation. The M3000F2 factor, in general, shown low variability. Akita (39.72° N, 140.13° E) showed the highest variability for the three frequencies. Moreover, it can be seen that quartiles are not equidistant from the median value.

  15. Evaluating Additive Interaction Using Survival Percentiles.

    PubMed

    Bellavia, Andrea; Bottai, Matteo; Orsini, Nicola

    2016-05-01

    Evaluation of statistical interaction in time-to-event analysis is usually limited to the study of multiplicative interaction, via inclusion of a product term in a Cox proportional-hazard model. Measures of additive interaction are available but seldom used. All measures of interaction in survival analysis, whether additive or multiplicative, are in the metric of hazard, usually assuming that the interaction between two predictors of interest is constant during the follow-up period. We introduce a measure to evaluate additive interaction in survival analysis in the metric of time. This measure can be calculated by evaluating survival percentiles, defined as the time points by which different subpopulations reach the same incidence proportion. Using this approach, the probability of the outcome is fixed and the time variable is estimated. We also show that by using a regression model for the evaluation of conditional survival percentiles, including a product term between the two exposures in the model, interaction is evaluated as a deviation from additivity of the effects. In the simple case of two binary exposures, the product term is interpreted as excess/decrease in survival time (i.e., years, months, days) due to the presence of both exposures. This measure of interaction is dependent on the fraction of events being considered, thus allowing evaluation of how interaction changes during the observed follow-up. Evaluation of interaction in the context of survival percentiles allows deriving a measure of additive interaction without assuming a constant effect over time, overcoming two main limitations of commonly used approaches.

  16. Trends and variability of East African rainfall and its relationship to the Mascarene High pressure system

    NASA Astrophysics Data System (ADS)

    Seregina, Larisa; Pinto, Joaquim G.; Fink, Andreas H.; Ermert, Volker

    2016-04-01

    In the recent decades, East Africa needs to deal with strong fluctuations in seasonal rainfall including precipitation extremes. In context of climate change, such extremes can become more frequent in the future. However, regional climate projections are uncertain about the future development of seasonal precipitation in the region. Rainfall regimes over East Africa are influenced by multiple factors, including two monsoon systems, several convergence zones and the Rift Valley lakes. In addition, local conditions, like topography, modulate the large-scale rainfall pattern. East African rainfall variability is also influenced by various teleconnections like the Indian Ocean Zonal Mode and El Niño Southern Oscillation. The study of past climate variability in East Africa requires sufficient observational data coverage in the region. As East Africa does not have a dense observational network of meteorological stations, satellite rainfall observations gain on importance in studies on climate variability in the region. The specific aim of the present study is the analysis of historic data from weather stations in East Africa (Kenya, Tanzania, Ruanda and Uganda), the use of gridded satellite products, and three-dimensional atmospheric reanalysis (e.g., ERA-Interim) to quantify climate variability in the recent past and to understand its causes. Climate variability and trends, including changes in extreme events, are evaluated using ETCCDI climate change and standardized precipitation indices. These climate indices are determined in order to investigate the variability of rainfall and its trends with the focus on recent decades. For seasonal trend analysis, an independent and non-calendaric rainfall onset criterion is introduced. In the follow-up, statistical and dynamical analyses are conducted to quantify the local impact of Mascarene High as a part of the Subtropical High Pressure Ridge on East African seasonal rainfall. Possible connections to pertinent large

  17. A model independent approach to inelastic dark matter scattering

    NASA Astrophysics Data System (ADS)

    Barello, G.; Chang, Spencer; Newby, Christopher A.

    2014-11-01

    We present a model independent analysis of inelastic dark matter transitions at direct detection experiments by modifying the elastic methodology of Fitzpatrick et al. By analyzing the kinematics of inelastic transitions, we find the relevant variables to describe these scattering processes, the primary change being a modification of the v→⊥ variable. Taking this into account, we list the relevant scattering matrix elements and modify the Mathematica package of Anand et al. to calculate the necessary form factors. As an application, we determine the matrix elements of inelastic scattering for spin transitions between a fermion to fermion, scalar to vector, and scalar to scalar. Finally, we consider fits to the DAMA/LIBRA annual modulation signal for the magnetic inelastic dark matter scenario as well as a model independent scan over relativistic operators, constraining them with limits from direct detection experiments. In the magnetic inelastic dark matter scenario or if the dark matter couples through relativistic operators involving only protons, we find that experiments with xenon and germanium targets can have consistently small rates. However, limits from iodine experiments are much more constraining, leaving small regions of allowed parameter space. We point out that existing uncertainties in the iodine quenching factor strongly affects the constraints, motivating further study to pin down the correct values.

  18. Variability study for saltstone

    SciTech Connect

    Harbour, J. R.; Edwards, T. B.; Hansen, E. K.; Williams, V. J.

    2005-10-01

    This report is a summary of the bench-scale experimental studies performed by the Savannah River National Laboratory (SRNL) for Waste Solidification Engineering (WSE) to establish the viability of a grout-based variability study. In order for a variability study to be useful, the property measurements of the fresh and cured Saltstone must be reproducible with an inherent variation that is small compared to the changes in the properties measured over the expected range of variability for a Salt Batch. This scoping task addressed the issue of reproducibility for Saltstone.

  19. Political attitudes develop independently of personality traits.

    PubMed

    Hatemi, Peter K; Verhulst, Brad

    2015-01-01

    The primary assumption within the recent personality and political orientations literature is that personality traits cause people to develop political attitudes. In contrast, research relying on traditional psychological and developmental theories suggests the relationship between most personality dimensions and political orientations are either not significant or weak. Research from behavioral genetics suggests the covariance between personality and political preferences is not causal, but due to a common, latent genetic factor that mutually influences both. The contradictory assumptions and findings from these research streams have yet to be resolved. This is in part due to the reliance on cross-sectional data and the lack of longitudinal genetically informative data. Here, using two independent longitudinal genetically informative samples, we examine the joint development of personality traits and attitude dimensions to explore the underlying causal mechanisms that drive the relationship between these features and provide a first step in resolving the causal question. We find change in personality over a ten-year period does not predict change in political attitudes, which does not support a causal relationship between personality traits and political attitudes as is frequently assumed. Rather, political attitudes are often more stable than the key personality traits assumed to be predicting them. Finally, the results from our genetic models find that no additional variance is accounted for by the causal pathway from personality traits to political attitudes. Our findings remain consistent with the original construction of the five-factor model of personality and developmental theories on attitude formation, but challenge recent work in this area. PMID:25734580

  20. Political Attitudes Develop Independently of Personality Traits

    PubMed Central

    Hatemi, Peter K.; Verhulst, Brad

    2015-01-01

    The primary assumption within the recent personality and political orientations literature is that personality traits cause people to develop political attitudes. In contrast, research relying on traditional psychological and developmental theories suggests the relationship between most personality dimensions and political orientations are either not significant or weak. Research from behavioral genetics suggests the covariance between personality and political preferences is not causal, but due to a common, latent genetic factor that mutually influences both. The contradictory assumptions and findings from these research streams have yet to be resolved. This is in part due to the reliance on cross-sectional data and the lack of longitudinal genetically informative data. Here, using two independent longitudinal genetically informative samples, we examine the joint development of personality traits and attitude dimensions to explore the underlying causal mechanisms that drive the relationship between these features and provide a first step in resolving the causal question. We find change in personality over a ten-year period does not predict change in political attitudes, which does not support a causal relationship between personality traits and political attitudes as is frequently assumed. Rather, political attitudes are often more stable than the key personality traits assumed to be predicting them. Finally, the results from our genetic models find that no additional variance is accounted for by the causal pathway from personality traits to political attitudes. Our findings remain consistent with the original construction of the five-factor model of personality and developmental theories on attitude formation, but challenge recent work in this area. PMID:25734580