Sample records for process external random

  1. Minimal-post-processing 320-Gbps true random bit generation using physical white chaos.

    PubMed

    Wang, Anbang; Wang, Longsheng; Li, Pu; Wang, Yuncai

    2017-02-20

    Chaotic external-cavity semiconductor laser (ECL) is a promising entropy source for generation of high-speed physical random bits or digital keys. The rate and randomness is unfortunately limited by laser relaxation oscillation and external-cavity resonance, and is usually improved by complicated post processing. Here, we propose using a physical broadband white chaos generated by optical heterodyning of two ECLs as entropy source to construct high-speed random bit generation (RBG) with minimal post processing. The optical heterodyne chaos not only has a white spectrum without signature of relaxation oscillation and external-cavity resonance but also has a symmetric amplitude distribution. Thus, after quantization with a multi-bit analog-digital-convertor (ADC), random bits can be obtained by extracting several least significant bits (LSBs) without any other processing. In experiments, a white chaos with a 3-dB bandwidth of 16.7 GHz is generated. Its entropy rate is estimated as 16 Gbps by single-bit quantization which means a spectrum efficiency of 96%. With quantization using an 8-bit ADC, 320-Gbps physical RBG is achieved by directly extracting 4 LSBs at 80-GHz sampling rate.

  2. The Prevention Program for Externalizing Problem Behavior (PEP) Improves Child Behavior by Reducing Negative Parenting: Analysis of Mediating Processes in a Randomized Controlled Trial

    ERIC Educational Resources Information Center

    Hanisch, Charlotte; Hautmann, Christopher; Plück, Julia; Eichelberger, Ilka; Döpfner, Manfred

    2014-01-01

    Background: Our indicated Prevention program for preschool children with Externalizing Problem behavior (PEP) demonstrated improved parenting and child problem behavior in a randomized controlled efficacy trial and in a study with an effectiveness design. The aim of the present analysis of data from the randomized controlled trial was to identify…

  3. Transient Oscilliations in Mechanical Systems of Automatic Control with Random Parameters

    NASA Astrophysics Data System (ADS)

    Royev, B.; Vinokur, A.; Kulikov, G.

    2018-04-01

    Transient oscillations in mechanical systems of automatic control with random parameters is a relevant but insufficiently studied issue. In this paper, a modified spectral method was applied to investigate the problem. The nature of dynamic processes and the phase portraits are analyzed depending on the amplitude and frequency of external influence. It is evident from the obtained results, that the dynamic phenomena occurring in the systems with random parameters under external influence are complex, and their study requires further investigation.

  4. The Temporal and Dynamic Nature of Self-Regulatory Processes during Independent and Externally Assisted Hypermedia Learning

    ERIC Educational Resources Information Center

    Johnson, Amy M.; Azevedo, Roger; D'Mello, Sidney K.

    2011-01-01

    This study examined the temporal and dynamic nature of students' self-regulatory processes while learning about the circulatory system with hypermedia. A total of 74 undergraduate students were randomly assigned to 1 of 2 conditions: independent learning or externally assisted learning. Participants in the independent learning condition used a…

  5. Random-order fractional bistable system and its stochastic resonance

    NASA Astrophysics Data System (ADS)

    Gao, Shilong; Zhang, Li; Liu, Hui; Kan, Bixia

    2017-01-01

    In this paper, the diffusion motion of Brownian particles in a viscous liquid suffering from stochastic fluctuations of the external environment is modeled as a random-order fractional bistable equation, and as a typical nonlinear dynamic behavior, the stochastic resonance phenomena in this system are investigated. At first, the derivation process of the random-order fractional bistable system is given. In particular, the random-power-law memory is deeply discussed to obtain the physical interpretation of the random-order fractional derivative. Secondly, the stochastic resonance evoked by random-order and external periodic force is mainly studied by numerical simulation. In particular, the frequency shifting phenomena of the periodical output are observed in SR induced by the excitation of the random order. Finally, the stochastic resonance of the system under the double stochastic excitations of the random order and the internal color noise is also investigated.

  6. Compositions, Random Sums and Continued Random Fractions of Poisson and Fractional Poisson Processes

    NASA Astrophysics Data System (ADS)

    Orsingher, Enzo; Polito, Federico

    2012-08-01

    In this paper we consider the relation between random sums and compositions of different processes. In particular, for independent Poisson processes N α ( t), N β ( t), t>0, we have that N_{α}(N_{β}(t)) stackrel{d}{=} sum_{j=1}^{N_{β}(t)} Xj, where the X j s are Poisson random variables. We present a series of similar cases, where the outer process is Poisson with different inner processes. We highlight generalisations of these results where the external process is infinitely divisible. A section of the paper concerns compositions of the form N_{α}(tauk^{ν}), ν∈(0,1], where tauk^{ν} is the inverse of the fractional Poisson process, and we show how these compositions can be represented as random sums. Furthermore we study compositions of the form Θ( N( t)), t>0, which can be represented as random products. The last section is devoted to studying continued fractions of Cauchy random variables with a Poisson number of levels. We evaluate the exact distribution and derive the scale parameter in terms of ratios of Fibonacci numbers.

  7. Chaotic oscillations and noise transformations in a simple dissipative system with delayed feedback

    NASA Astrophysics Data System (ADS)

    Zverev, V. V.; Rubinstein, B. Ya.

    1991-04-01

    We analyze the statistical behavior of signals in nonlinear circuits with delayed feedback in the presence of external Markovian noise. For the special class of circuits with intense phase mixing we develop an approach for the computation of the probability distributions and multitime correlation functions based on the random phase approximation. Both Gaussian and Kubo-Andersen models of external noise statistics are analyzed and the existence of the stationary (asymptotic) random process in the long-time limit is shown. We demonstrate that a nonlinear system with chaotic behavior becomes a noise amplifier with specific statistical transformation properties.

  8. Random and externally controlled occurrences of Dansgaard-Oeschger events

    NASA Astrophysics Data System (ADS)

    Lohmann, Johannes; Ditlevsen, Peter D.

    2018-05-01

    Dansgaard-Oeschger (DO) events constitute the most pronounced mode of centennial to millennial climate variability of the last glacial period. Since their discovery, many decades of research have been devoted to understand the origin and nature of these rapid climate shifts. In recent years, a number of studies have appeared that report emergence of DO-type variability in fully coupled general circulation models via different mechanisms. These mechanisms result in the occurrence of DO events at varying degrees of regularity, ranging from periodic to random. When examining the full sequence of DO events as captured in the North Greenland Ice Core Project (NGRIP) ice core record, one can observe high irregularity in the timing of individual events at any stage within the last glacial period. In addition to the prevailing irregularity, certain properties of the DO event sequence, such as the average event frequency or the relative distribution of cold versus warm periods, appear to be changing throughout the glacial. By using statistical hypothesis tests on simple event models, we investigate whether the observed event sequence may have been generated by stationary random processes or rather was strongly modulated by external factors. We find that the sequence of DO warming events is consistent with a stationary random process, whereas dividing the event sequence into warming and cooling events leads to inconsistency with two independent event processes. As we include external forcing, we find a particularly good fit to the observed DO sequence in a model where the average residence time in warm periods are controlled by global ice volume and cold periods by boreal summer insolation.

  9. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Krasnobaeva, L. A., E-mail: kla1983@mail.ru; Siberian State Medical University Moscowski Trakt 2, Tomsk, 634050; Shapovalov, A. V.

    Within the formalism of the Fokker–Planck equation, the influence of nonstationary external force, random force, and dissipation effects on dynamics local conformational perturbations (kink) propagating along the DNA molecule is investigated. Such waves have an important role in the regulation of important biological processes in living systems at the molecular level. As a dynamic model of DNA was used a modified sine-Gordon equation, simulating the rotational oscillations of bases in one of the chains DNA. The equation of evolution of the kink momentum is obtained in the form of the stochastic differential equation in the Stratonovich sense within the frameworkmore » of the well-known McLaughlin and Scott energy approach. The corresponding Fokker–Planck equation for the momentum distribution function coincides with the equation describing the Ornstein–Uhlenbek process with a regular nonstationary external force. The influence of the nonlinear stochastic effects on the kink dynamics is considered with the help of the Fokker– Planck nonlinear equation with the shift coefficient dependent on the first moment of the kink momentum distribution function. Expressions are derived for average value and variance of the momentum. Examples are considered which demonstrate the influence of the external regular and random forces on the evolution of the average value and variance of the kink momentum. Within the formalism of the Fokker–Planck equation, the influence of nonstationary external force, random force, and dissipation effects on the kink dynamics is investigated in the sine–Gordon model. The equation of evolution of the kink momentum is obtained in the form of the stochastic differential equation in the Stratonovich sense within the framework of the well-known McLaughlin and Scott energy approach. The corresponding Fokker–Planck equation for the momentum distribution function coincides with the equation describing the Ornstein–Uhlenbek process with a regular nonstationary external force. The influence of the nonlinear stochastic effects on the kink dynamics is considered with the help of the Fokker–Planck nonlinear equation with the shift coefficient dependent on the first moment of the kink momentum distribution function. Expressions are derived for average value and variance of the momentum. Examples are considered which demonstrate the influence of the external regular and random forces on the evolution of the average value and variance of the kink momentum.« less

  10. Lattice Boltzmann simulation of the gas-solid adsorption process in reconstructed random porous media.

    PubMed

    Zhou, L; Qu, Z G; Ding, T; Miao, J Y

    2016-04-01

    The gas-solid adsorption process in reconstructed random porous media is numerically studied with the lattice Boltzmann (LB) method at the pore scale with consideration of interparticle, interfacial, and intraparticle mass transfer performances. Adsorbent structures are reconstructed in two dimensions by employing the quartet structure generation set approach. To implement boundary conditions accurately, all the porous interfacial nodes are recognized and classified into 14 types using a proposed universal program called the boundary recognition and classification program. The multiple-relaxation-time LB model and single-relaxation-time LB model are adopted to simulate flow and mass transport, respectively. The interparticle, interfacial, and intraparticle mass transfer capacities are evaluated with the permeability factor and interparticle transfer coefficient, Langmuir adsorption kinetics, and the solid diffusion model, respectively. Adsorption processes are performed in two groups of adsorbent media with different porosities and particle sizes. External and internal mass transfer resistances govern the adsorption system. A large porosity leads to an early time for adsorption equilibrium because of the controlling factor of external resistance. External and internal resistances are dominant at small and large particle sizes, respectively. Particle size, under which the total resistance is minimum, ranges from 3 to 7 μm with the preset parameters. Pore-scale simulation clearly explains the effect of both external and internal mass transfer resistances. The present paper provides both theoretical and practical guidance for the design and optimization of adsorption systems.

  11. Lattice Boltzmann simulation of the gas-solid adsorption process in reconstructed random porous media

    NASA Astrophysics Data System (ADS)

    Zhou, L.; Qu, Z. G.; Ding, T.; Miao, J. Y.

    2016-04-01

    The gas-solid adsorption process in reconstructed random porous media is numerically studied with the lattice Boltzmann (LB) method at the pore scale with consideration of interparticle, interfacial, and intraparticle mass transfer performances. Adsorbent structures are reconstructed in two dimensions by employing the quartet structure generation set approach. To implement boundary conditions accurately, all the porous interfacial nodes are recognized and classified into 14 types using a proposed universal program called the boundary recognition and classification program. The multiple-relaxation-time LB model and single-relaxation-time LB model are adopted to simulate flow and mass transport, respectively. The interparticle, interfacial, and intraparticle mass transfer capacities are evaluated with the permeability factor and interparticle transfer coefficient, Langmuir adsorption kinetics, and the solid diffusion model, respectively. Adsorption processes are performed in two groups of adsorbent media with different porosities and particle sizes. External and internal mass transfer resistances govern the adsorption system. A large porosity leads to an early time for adsorption equilibrium because of the controlling factor of external resistance. External and internal resistances are dominant at small and large particle sizes, respectively. Particle size, under which the total resistance is minimum, ranges from 3 to 7 μm with the preset parameters. Pore-scale simulation clearly explains the effect of both external and internal mass transfer resistances. The present paper provides both theoretical and practical guidance for the design and optimization of adsorption systems.

  12. A Hybrid Process Fidelity Assessment in a Home-based Randomized Clinical Trial

    PubMed Central

    WILDE, MARY H.; LIEBEL, DIANNE; FAIRBANKS, EILEEN; WILSON, PAULA; LASH, MARGARET; SHAH, SHIVANI; McDONALD, MARGARET V.; BRASCH, JUDITH; ZHANG, FENG; SCHEID, EILEEN; McMAHON, JAMES M.

    2016-01-01

    A process fidelity assessment was conducted as a nested study within a home-based randomized clinical trial teaching self-management to 101 long-term indwelling urinary catheter users in the treatment group. Our hybrid model combined external assessments (outside observations and tape recordings) with internal evaluation methods (through study nurse forms and notes) for a comprehensive process fidelity assessment. Barriers, patient-related issues, and nurse perspectives were identified demonstrating the complexity in home care intervention research. The complementary and synergistic approaches provided in depth information about the context of the delivery and the impact of the intervention on study outcomes. PMID:25894688

  13. Can a combination of average of normals and "real time" External Quality Assurance replace Internal Quality Control?

    PubMed

    Badrick, Tony; Graham, Peter

    2018-03-28

    Internal Quality Control and External Quality Assurance are separate but related processes that have developed independently in laboratory medicine over many years. They have different sample frequencies, statistical interpretations and immediacy. Both processes have evolved absorbing new understandings of the concept of laboratory error, sample material matrix and assay capability. However, we do not believe at the coalface that either process has led to much improvement in patient outcomes recently. It is the increasing reliability and automation of analytical platforms along with improved stability of reagents that has reduced systematic and random error, which in turn has minimised the risk of running less frequent IQC. We suggest that it is time to rethink the role of both these processes and unite them into a single approach using an Average of Normals model supported by more frequent External Quality Assurance samples. This new paradigm may lead to less confusion for laboratory staff and quicker responses to and identification of out of control situations.

  14. Issue Scanning: Finding the Future...Maybe.

    ERIC Educational Resources Information Center

    Plog, Michael; Sweeney, Jim; Weiss, Barry

    Issue Scanning, sometimes called Environmental Scanning, is used in many business, government, educational, and nonprofit organizations. The technique is supposed to monitor the "pulse" of the external environment. The scanning process should lessen the randomness of the information used in decision making, and it should alert managers…

  15. A reduced-form intensity-based model under fuzzy environments

    NASA Astrophysics Data System (ADS)

    Wu, Liang; Zhuang, Yaming

    2015-05-01

    The external shocks and internal contagion are the important sources of default events. However, the external shocks and internal contagion effect on the company is not observed, we cannot get the accurate size of the shocks. The information of investors relative to the default process exhibits a certain fuzziness. Therefore, using randomness and fuzziness to study such problems as derivative pricing or default probability has practical needs. But the idea of fuzzifying credit risk models is little exploited, especially in a reduced-form model. This paper proposes a new default intensity model with fuzziness and presents a fuzzy default probability and default loss rate, and puts them into default debt and credit derivative pricing. Finally, the simulation analysis verifies the rationality of the model. Using fuzzy numbers and random analysis one can consider more uncertain sources in the default process of default and investors' subjective judgment on the financial markets in a variety of fuzzy reliability so as to broaden the scope of possible credit spreads.

  16. Robustness of near-infrared calibration models for the prediction of milk constituents during the milking process.

    PubMed

    Melfsen, Andreas; Hartung, Eberhard; Haeussermann, Angelika

    2013-02-01

    The robustness of in-line raw milk analysis with near-infrared spectroscopy (NIRS) was tested with respect to the prediction of the raw milk contents fat, protein and lactose. Near-infrared (NIR) spectra of raw milk (n = 3119) were acquired on three different farms during the milking process of 354 milkings over a period of six months. Calibration models were calculated for: a random data set of each farm (fully random internal calibration); first two thirds of the visits per farm (internal calibration); whole datasets of two of the three farms (external calibration), and combinations of external and internal datasets. Validation was done either on the remaining data set per farm (internal validation) or on data of the remaining farms (external validation). Excellent calibration results were obtained when fully randomised internal calibration sets were used for milk analysis. In this case, RPD values of around ten, five and three for the prediction of fat, protein and lactose content, respectively, were achieved. Farm internal calibrations achieved much poorer prediction results especially for the prediction of protein and lactose with RPD values of around two and one respectively. The prediction accuracy improved when validation was done on spectra of an external farm, mainly due to the higher sample variation in external calibration sets in terms of feeding diets and individual cow effects. The results showed that further improvements were achieved when additional farm information was added to the calibration set. One of the main requirements towards a robust calibration model is the ability to predict milk constituents in unknown future milk samples. The robustness and quality of prediction increases with increasing variation of, e.g., feeding and cow individual milk composition in the calibration model.

  17. Image discrimination models predict detection in fixed but not random noise

    NASA Technical Reports Server (NTRS)

    Ahumada, A. J. Jr; Beard, B. L.; Watson, A. B. (Principal Investigator)

    1997-01-01

    By means of a two-interval forced-choice procedure, contrast detection thresholds for an aircraft positioned on a simulated airport runway scene were measured with fixed and random white-noise masks. The term fixed noise refers to a constant, or unchanging, noise pattern for each stimulus presentation. The random noise was either the same or different in the two intervals. Contrary to simple image discrimination model predictions, the same random noise condition produced greater masking than the fixed noise. This suggests that observers seem unable to hold a new noisy image for comparison. Also, performance appeared limited by internal process variability rather than by external noise variability, since similar masking was obtained for both random noise types.

  18. The role of external evidence in data monitoring of a clinical trial.

    PubMed

    Pocock, S J

    1996-06-30

    Data monitoring of interim results from a randomized clinical trial should take into consideration evidence from other trials. This article presents both scientific and practical issues regarding the pros and cons of formally incorporating such external evidence into the decision making process for the current trial. Guidelines on how to use other trials' data are presented, along with cautiously sceptical comments on the impracticality of using formal meta-analyses in data monitoring. The arguments are illustrated by recent examples from specific trials, and the article concludes with some general recommendations.

  19. On a Stochastic Failure Model under Random Shocks

    NASA Astrophysics Data System (ADS)

    Cha, Ji Hwan

    2013-02-01

    In most conventional settings, the events caused by an external shock are initiated at the moments of its occurrence. In this paper, we study a new classes of shock model, where each shock from a nonhomogeneous Poisson processes can trigger a failure of a system not immediately, as in classical extreme shock models, but with delay of some random time. We derive the corresponding survival and failure rate functions. Furthermore, we study the limiting behaviour of the failure rate function where it is applicable.

  20. A new fundamental model of moving particle for reinterpreting Schroedinger equation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Umar, Muhamad Darwis

    2012-06-20

    The study of Schroedinger equation based on a hypothesis that every particle must move randomly in a quantum-sized volume has been done. In addition to random motion, every particle can do relative motion through the movement of its quantum-sized volume. On the other way these motions can coincide. In this proposed model, the random motion is one kind of intrinsic properties of the particle. The every change of both speed of randomly intrinsic motion and or the velocity of translational motion of a quantum-sized volume will represent a transition between two states, and the change of speed of randomly intrinsicmore » motion will generate diffusion process or Brownian motion perspectives. Diffusion process can take place in backward and forward processes and will represent a dissipative system. To derive Schroedinger equation from our hypothesis we use time operator introduced by Nelson. From a fundamental analysis, we find out that, naturally, we should view the means of Newton's Law F(vector sign) = ma(vector sign) as no an external force, but it is just to describe both the presence of intrinsic random motion and the change of the particle energy.« less

  1. Can Findings from Randomized Controlled Trials of Social Skills Training in Autism Spectrum Disorder Be Generalized? The Neglected Dimension of External Validity

    ERIC Educational Resources Information Center

    Jonsson, Ulf; Olsson, Nora Choque; Bölte, Sven

    2016-01-01

    Systematic reviews have traditionally focused on internal validity, while external validity often has been overlooked. In this study, we systematically reviewed determinants of external validity in the accumulated randomized controlled trials of social skills group interventions for children and adolescents with autism spectrum disorder. We…

  2. Direct generation of all-optical random numbers from optical pulse amplitude chaos.

    PubMed

    Li, Pu; Wang, Yun-Cai; Wang, An-Bang; Yang, Ling-Zhen; Zhang, Ming-Jiang; Zhang, Jian-Zhong

    2012-02-13

    We propose and theoretically demonstrate an all-optical method for directly generating all-optical random numbers from pulse amplitude chaos produced by a mode-locked fiber ring laser. Under an appropriate pump intensity, the mode-locked laser can experience a quasi-periodic route to chaos. Such a chaos consists of a stream of pulses with a fixed repetition frequency but random intensities. In this method, we do not require sampling procedure and external triggered clocks but directly quantize the chaotic pulses stream into random number sequence via an all-optical flip-flop. Moreover, our simulation results show that the pulse amplitude chaos has no periodicity and possesses a highly symmetric distribution of amplitude. Thus, in theory, the obtained random number sequence without post-processing has a high-quality randomness verified by industry-standard statistical tests.

  3. Can Dual Task Walking Improve in Parkinson's Disease After External Focus of Attention Exercise? A Single Blind Randomized Controlled Trial.

    PubMed

    Beck, Eric N; Intzandt, Brittany N; Almeida, Quincy J

    2018-01-01

    It may be possible to use attention-based exercise to decrease demands associated with walking in Parkinson's disease (PD), and thus improve dual task walking ability. For example, an external focus of attention (focusing on the effect of an action on the environment) may recruit automatic control processes degenerated in PD, whereas an internal focus (limb movement) may recruit conscious (nonautomatic) control processes. Thus, we aimed to investigate how externally and internally focused exercise influences dual task walking and symptom severity in PD. Forty-seven participants with PD were randomized to either an Externally (n = 24) or Internally (n = 23) focused group and completed 33 one-hour attention-based exercise sessions over 11 weeks. In addition, 16 participants were part of a control group. Before, after, and 8 weeks following the program (pre/post/washout), gait patterns were measured during single and dual task walking (digit-monitoring task, ie, walking while counting numbers announced by an audio-track), and symptom severity (UPDRS-III) was assessed ON and OFF dopamine replacement. Pairwise comparisons (95% confidence intervals [CIs]) and repeated-measures analyses of variance were conducted. Pre to post: Dual task step time decreased in the external group (Δ = 0.02 seconds, CI 0.01-0.04). Dual task step length (Δ = 2.3 cm, CI 0.86-3.75) and velocity (Δ = 4.5 cm/s, CI 0.59-8.48) decreased (became worse) in the internal group. UPDRS-III scores (ON and OFF) decreased (improved) in only the External group. Pre to washout: Dual task step time ( P = .005) and percentage in double support ( P = .014) significantly decreased (improved) in both exercise groups, although only the internal group increased error on the secondary counting task (ie, more errors monitoring numbers). UPDRS-III scores in both exercise groups significantly decreased ( P = .001). Since dual task walking improvements were found immediately, and 8 weeks after the cessation of an externally focused exercise program, we conclude that externally focused exercise may improve on functioning of automatic control networks in PD. Internally focused exercise hindered dual tasking ability. Overall, externally focused exercise led to greater rehabilitation benefits in dual tasking and motor symptoms compared with internally focused exercise.

  4. A Randomized Controlled Trial of a Standardized Behavior Management Intervention for Students with Externalizing Behavior

    ERIC Educational Resources Information Center

    Forster, Martin; Sundell, Knut; Morris, Richard J.; Karlberg, Martin; Melin, Lennart

    2012-01-01

    This study reports the results from a Swedish randomized controlled trial of a standardized behavior management intervention. The intervention targeted students with externalizing behavior in a regular education setting. First- and second-grade students (N = 100) from 38 schools were randomly assigned to either the intervention or an active…

  5. External cephalic version for breech presentation with or without spinal analgesia in nulliparous women at term: a randomized controlled trial.

    PubMed

    Weiniger, Carolyn F; Ginosar, Yehuda; Elchalal, Uriel; Sharon, Einav; Nokrian, Malka; Ezra, Yossef

    2007-12-01

    To compare the success of external cephalic version using spinal analgesia with no analgesia among nulliparas. A prospective randomized controlled trial was performed in a tertiary referral center delivery suite. Nulliparous women at term requesting external cephalic version for breech presentation were randomized to receive spinal analgesia (7.5 mg bupivacaine) or no analgesia before the external cephalic version. An experienced obstetrician performed the external cephalic version. Primary outcome was successful conversion to vertex presentation. Seventy-four women were enrolled, and 70 analyzed (36 spinal, 34 no analgesia). Successful external cephalic version occurred among 24 of 36 (66.7%) women randomized to receive spinal analgesia compared with 11 of 34 (32.4%) without, P=.004 (95% confidence interval [CI] of the difference: 0.0954-0.5513). External cephalic version with spinal analgesia resulted in a lower visual analog pain score, 1.76+/-2.74 compared with 6.84+/-3.08 without, P<.001. A secondary analysis logistic regression model demonstrated that the odds of external cephalic version success was 4.0-fold higher when performed with spinal analgesia P=.02 (95% CI, odds ratio [OR] 1.2-12.9). Complete breech presentation before attempting external cephalic version increased the odds of success 8.2-fold, P=.001 (95% CI, OR 2.2-30.3). Placental position, estimated fetal weight, and maternal weight did not contribute to the success rate when spinal analgesia was used. There were no cases of placental abruption or fetal distress. Administration of spinal analgesia significantly increases the success rate of external cephalic version among nulliparous women at term, which allows possible normal vaginal delivery. ClinicalTrials.gov, www.clinicaltrials.gov, NCT00119184 I.

  6. [Methodological quality of an article on the treatment of gastric cancer adopted as protocol by some Chilean hospitals].

    PubMed

    Manterola, Carlos; Torres, Rodrigo; Burgos, Luis; Vial, Manuel; Pineda, Viviana

    2006-07-01

    Surgery is a curative treatment for gastric cancer (GC). As relapse is frequent, adjuvant therapies such as postoperative chemo radiotherapy have been tried. In Chile, some hospitals adopted Macdonald's study as a protocol for the treatment of GC. To determine methodological quality and internal and external validity of the Macdonald study. Three instruments were applied that assess methodological quality. A critical appraisal was done and the internal and external validity of the methodological quality was analyzed with two scales: MINCIR (Methodology and Research in Surgery), valid for therapy studies and CONSORT (Consolidated Standards of Reporting Trials), valid for randomized controlled trials (RCT). Guides and scales were applied by 5 researchers with training in clinical epidemiology. The reader's guide verified that the Macdonald study was not directed to answer a clearly defined question. There was random assignment, but the method used is not described and the patients were not considered until the end of the study (36% of the group with surgery plus chemo radiotherapy did not complete treatment). MINCIR scale confirmed a multicentric RCT, not blinded, with an unclear randomized sequence, erroneous sample size estimation, vague objectives and no exclusion criteria. CONSORT system proved the lack of working hypothesis and specific objectives as well as an absence of exclusion criteria and identification of the primary variable, an imprecise estimation of sample size, ambiguities in the randomization process, no blinding, an absence of statistical adjustment and the omission of a subgroup analysis. The instruments applied demonstrated methodological shortcomings that compromise the internal and external validity of the.

  7. Hybrid computing using a neural network with dynamic external memory.

    PubMed

    Graves, Alex; Wayne, Greg; Reynolds, Malcolm; Harley, Tim; Danihelka, Ivo; Grabska-Barwińska, Agnieszka; Colmenarejo, Sergio Gómez; Grefenstette, Edward; Ramalho, Tiago; Agapiou, John; Badia, Adrià Puigdomènech; Hermann, Karl Moritz; Zwols, Yori; Ostrovski, Georg; Cain, Adam; King, Helen; Summerfield, Christopher; Blunsom, Phil; Kavukcuoglu, Koray; Hassabis, Demis

    2016-10-27

    Artificial neural networks are remarkably adept at sensory processing, sequence learning and reinforcement learning, but are limited in their ability to represent variables and data structures and to store data over long timescales, owing to the lack of an external memory. Here we introduce a machine learning model called a differentiable neural computer (DNC), which consists of a neural network that can read from and write to an external memory matrix, analogous to the random-access memory in a conventional computer. Like a conventional computer, it can use its memory to represent and manipulate complex data structures, but, like a neural network, it can learn to do so from data. When trained with supervised learning, we demonstrate that a DNC can successfully answer synthetic questions designed to emulate reasoning and inference problems in natural language. We show that it can learn tasks such as finding the shortest path between specified points and inferring the missing links in randomly generated graphs, and then generalize these tasks to specific graphs such as transport networks and family trees. When trained with reinforcement learning, a DNC can complete a moving blocks puzzle in which changing goals are specified by sequences of symbols. Taken together, our results demonstrate that DNCs have the capacity to solve complex, structured tasks that are inaccessible to neural networks without external read-write memory.

  8. The effects of computer-assisted instruction and locus of control upon preservice elementary teachers' acquisition of the integrated science process skills

    NASA Astrophysics Data System (ADS)

    Wesley, Beth Eddinger; Krockover, Gerald H.; Devito, Alfred

    The purpose of this study was to determine the effects of computer-assisted instruction (CAI) versus a text mode of programmed instruction (PI), and the cognitive style of locus of control, on preservice elementary teachers' achievement of the integrated science process skills. Eighty-one preservice elementary teachers in six sections of a science methods class were classified as internally or externally controlled. The sections were randomly assigned to receive instruction in the integrated science process skills via a microcomputer or printed text. The study used a pretest-posttest control group design. Before assessing main and interaction effects, analysis of covariance was used to adjust posttest scores using the pretest scores. Statistical analysis revealed that main effects were not significant. Additionally, no interaction effects between treatments and loci of control were demonstrated. The results suggest that printed PI and tutorial CAI are equally effective modes of instruction for teaching internally and externally oriented preservice elementary teachers the integrated science process skills.

  9. Does rational selection of training and test sets improve the outcome of QSAR modeling?

    PubMed

    Martin, Todd M; Harten, Paul; Young, Douglas M; Muratov, Eugene N; Golbraikh, Alexander; Zhu, Hao; Tropsha, Alexander

    2012-10-22

    Prior to using a quantitative structure activity relationship (QSAR) model for external predictions, its predictive power should be established and validated. In the absence of a true external data set, the best way to validate the predictive ability of a model is to perform its statistical external validation. In statistical external validation, the overall data set is divided into training and test sets. Commonly, this splitting is performed using random division. Rational splitting methods can divide data sets into training and test sets in an intelligent fashion. The purpose of this study was to determine whether rational division methods lead to more predictive models compared to random division. A special data splitting procedure was used to facilitate the comparison between random and rational division methods. For each toxicity end point, the overall data set was divided into a modeling set (80% of the overall set) and an external evaluation set (20% of the overall set) using random division. The modeling set was then subdivided into a training set (80% of the modeling set) and a test set (20% of the modeling set) using rational division methods and by using random division. The Kennard-Stone, minimal test set dissimilarity, and sphere exclusion algorithms were used as the rational division methods. The hierarchical clustering, random forest, and k-nearest neighbor (kNN) methods were used to develop QSAR models based on the training sets. For kNN QSAR, multiple training and test sets were generated, and multiple QSAR models were built. The results of this study indicate that models based on rational division methods generate better statistical results for the test sets than models based on random division, but the predictive power of both types of models are comparable.

  10. Randomized controlled trial of internal and external targeted temperature management methods in post- cardiac arrest patients.

    PubMed

    Look, Xinqi; Li, Huihua; Ng, Mingwei; Lim, Eric Tien Siang; Pothiawala, Sohil; Tan, Kenneth Boon Kiat; Sewa, Duu Wen; Shahidah, Nur; Pek, Pin Pin; Ong, Marcus Eng Hock

    2018-01-01

    Targeted temperature management post-cardiac arrest is currently implemented using various methods, broadly categorized as internal and external. This study aimed to evaluate survival-to-hospital discharge and neurological outcomes (Glasgow-Pittsburgh Score) of post-cardiac arrest patients undergoing internal cooling verses external cooling. A randomized controlled trial of post-resuscitation cardiac arrest patients was conducted from October 2008-September 2014. Patients were randomized to either internal or external cooling methods. Historical controls were selected matched by age and gender. Analysis using SPSS version 21.0 presented descriptive statistics and frequencies while univariate logistic regression was done using R 3.1.3. 23 patients were randomized to internal cooling and 22 patients to external cooling and 42 matched controls were selected. No significant difference was seen between internal and external cooling in terms of survival, neurological outcomes and complications. However in the internal cooling arm, there was lower risk of developing overcooling (p=0.01) and rebound hyperthermia (p=0.02). Compared to normothermia, internal cooling had higher survival (OR=3.36, 95% CI=(1.130, 10.412), and lower risk of developing cardiac arrhythmias (OR=0.18, 95% CI=(0.04, 0.63)). Subgroup analysis showed those with cardiac cause of arrest (OR=4.29, 95% CI=(1.26, 15.80)) and sustained ROSC (OR=5.50, 95% CI=(1.64, 20.39)) had better survival with internal cooling compared to normothermia. Cooling curves showed tighter temperature control for internal compared to external cooling. Internal cooling showed tighter temperature control compared to external cooling. Internal cooling can potentially provide better survival-to-hospital discharge outcomes and reduce cardiac arrhythmia complications in carefully selected patients as compared to normothermia. Copyright © 2017. Published by Elsevier Inc.

  11. [Patient's individuality and application of guidelines in surgery].

    PubMed

    Schulte, Michael

    2005-01-01

    Individual treatment decisions can become considerably conflictual in view of the co-existence of medical professional guidelines, recommendations based on evidence-based medicine (EBM), and juridical and economical directions. Medical guidelines are not subject to an external review process; also, due to reduced practicability, the surgeons' compliance with guidelines remains relatively low. Surgical treatment strategies can rely on randomized clinical trials (RCTs) in approximately 20% of the surgical procedures and on non-randomized trials in approximately 70% of the cases. No evidence is given in approximately 10% of the cases. Specific problems of implementation of EBM in surgical disciplines are represented by the difficulty of standardized procedures, the heterogeneity of the population, the impossibility to conduct double-blinded RCTs, a low statistical power, and a publication bias. Since individual diseases cannot be reduced to surgical cases manageable only by the application of guidelines, adequate treatment of individual patients requires the critical application of both external evidence and surgeon expertise (internal evidence).

  12. Changing Teacher-Child Dyadic Interactions to Improve Preschool Children's Externalizing Behaviors

    ERIC Educational Resources Information Center

    Williford, Amanda P.; LoCasale-Crouch, Jennifer; Whittaker, Jessica Vick; DeCoster, Jamie; Hartz, Karyn A.; Carter, Lauren M.; Wolcott, Catherine Sanger; Hatfield, Bridget E.

    2017-01-01

    A randomized controlled trial was used to examine the impact of an attachment-based, teacher-child, dyadic intervention (Banking Time) to improve children's externalizing behavior. Participants included 183 teachers and 470 preschool children (3-4 years of age). Classrooms were randomly assigned to Banking Time, child time, or business as usual…

  13. Associations between positive parenting practices and child externalizing behavior in underserved Latino immigrant families.

    PubMed

    Holtrop, Kendal; McNeil Smith, Sharde'; Scott, Jenna C

    2015-06-01

    This study examined whether five specific parenting practices (i.e., monitoring, discipline, skill encouragement, problem solving, and positive involvement) were associated with reduced child externalizing behaviors among a sample of Latino immigrant families. It utilized baseline data from 83 Latino couples with children participating in a larger randomized controlled trial of a culturally adapted parenting intervention. Results reveal that monitoring, discipline, skill encouragement, and problem solving each made independent contributions to the prediction of child externalizing behavior, although not all in the expected direction. Further analyses examining mothers and fathers separately suggest that mother-reported monitoring and father-reported discipline practices uniquely contributed to these findings. These results may have important implications for prevention and clinical intervention efforts with Latino immigrant families, including the cultural adaptation and implementation of parenting interventions with this underserved population. © 2014 Family Process Institute.

  14. Nifedipine as a uterine relaxant for external cephalic version: a randomized controlled trial.

    PubMed

    Kok, Marjolein; Bais, Joke M; van Lith, Jan M; Papatsonis, Dimitri M; Kleiverda, Gunilla; Hanny, Dahrs; Doornbos, Johannes P; Mol, Ben W; van der Post, Joris A

    2008-08-01

    To estimate the effectiveness of nifedipine as a uterine relaxant during external cephalic version to correct breech presentation. In this randomized, double-blind, placebo-controlled trial, women with a singleton fetus in breech presentation and a gestational age of 36 weeks or more were eligible for enrollment. Participating women received two doses of either nifedipine 10 mg or placebo, 30 and 15 minutes before the external cephalic version attempt. The primary outcome was a cephalic-presenting fetus immediately after the procedure. Secondary outcome measures were cephalic presentation at delivery, mode of delivery, and adverse events. A sample size of 292 was calculated to provide 80% power to detect a 17% improvement of the external cephalic version success rate, assuming a placebo group rate of 40% and alpha of .05. Outcome data for 310 of 320 randomly assigned participants revealed no significant difference in external cephalic version success rates between treatment (42%) and control group (37%) (relative risk 1.1, 95%; 95% confidence interval 0.85-1.5). The cesarean delivery rate was 51% in the treatment group and 46% in the control group (relative risk 1.1, 95% confidence interval 0.88-1.4). Nifedipine did not significantly improve the success of external cephalic version. Future use of nifedipine to improve the outcome of external cephalic version should be limited to large clinical trials.

  15. Averaging of phase noise in PSK signals by an opto-electrical feed-forward circuit

    NASA Astrophysics Data System (ADS)

    Inoue, K.; Ohta, M.

    2013-10-01

    This paper proposes an opto-electrical feed-forward circuit that reduces phase noise in binary PSK signals by averaging the noise. Random and independent phase noise is averaged over several bit slots by externally modulating a phase-fluctuating PSK signal with feed-forward signal obtained from signal processing of the outputs of delay interferometers. The simulation results demonstrate a reduction in the phase noise.

  16. Transition in the decay rates of stationary distributions of Lévy motion in an energy landscape.

    PubMed

    Kaleta, Kamil; Lőrinczi, József

    2016-02-01

    The time evolution of random variables with Lévy statistics has the ability to develop jumps, displaying very different behaviors from continuously fluctuating cases. Such patterns appear in an ever broadening range of examples including random lasers, non-Gaussian kinetics, or foraging strategies. The penalizing or reinforcing effect of the environment, however, has been little explored so far. We report a new phenomenon which manifests as a qualitative transition in the spatial decay behavior of the stationary measure of a jump process under an external potential, occurring on a combined change in the characteristics of the process and the lowest eigenvalue resulting from the effect of the potential. This also provides insight into the fundamental question of what is the mechanism of the spatial decay of a ground state.

  17. Effects of physical randomness training on virtual and laboratory golf putting performance in novices.

    PubMed

    Pataky, T C; Lamb, P F

    2018-06-01

    External randomness exists in all sports but is perhaps most obvious in golf putting where robotic putters sink only 80% of 5 m putts due to unpredictable ball-green dynamics. The purpose of this study was to test whether physical randomness training can improve putting performance in novices. A virtual random-physics golf-putting game was developed based on controlled ball-roll data. Thirty-two subjects were assigned a unique randomness gain (RG) ranging from 0.1 to 2.0-times real-world randomness. Putter face kinematics were measured in 5 m laboratory putts before and after five days of virtual training. Performance was quantified using putt success rate and "miss-adjustment correlation" (MAC), the correlation between left-right miss magnitude and subsequent right-left kinematic adjustments. Results showed no RG-success correlation (r = -0.066, p = 0.719) but mildly stronger correlations with MAC for face angle (r = -0.168, p = 0.358) and clubhead path (r = -0.302, p = 0.093). The strongest RG-MAC correlation was observed during virtual training (r = -0.692, p < 0.001). These results suggest that subjects quickly adapt to physical randomness in virtual training, and also that this learning may weakly transfer to real golf putting kinematics. Adaptation to external physical randomness during virtual training may therefore help golfers adapt to external randomness in real-world environments.

  18. Neuraxial analgesia to increase the success rate of external cephalic version: a systematic review and meta-analysis of randomized controlled trials.

    PubMed

    Magro-Malosso, Elena Rita; Saccone, Gabriele; Di Tommaso, Mariarosaria; Mele, Michele; Berghella, Vincenzo

    2016-09-01

    External cephalic version is a medical procedure in which the fetus is externally manipulated to assume the cephalic presentation. The use of neuraxial analgesia for facilitating the version has been evaluated in several randomized clinical trials, but its potential effects are still controversial. The objective of the study was to evaluate the effectiveness of neuraxial analgesia as an intervention to increase the success rate of external cephalic version. Searches were performed in electronic databases with the use of a combination of text words related to external cephalic version and neuraxial analgesia from the inception of each database to January 2016. We included all randomized clinical trials of women, with a gestational age ≥36 weeks and breech or transverse fetal presentation, undergoing external cephalic version who were randomized to neuraxial analgesia, including spinal, epidural, or combined spinal-epidural techniques (ie, intervention group) or to a control group (either intravenous analgesia or no treatment). The primary outcome was the successful external cephalic version. The summary measures were reported as relative risk or as mean differences with a 95% confidence interval. Nine randomized clinical trials (934 women) were included in this review. Women who received neuraxial analgesia had a significantly higher incidence of successful external cephalic version (58.4% vs 43.1%; relative risk, 1.44, 95% confidence interval, 1.27-1.64), cephalic presentation in labor (55.1% vs 40.2%; relative risk, 1.37, 95% confidence interval, 1.08-1.73), and vaginal delivery (54.0% vs 44.6%; relative risk, 1.21, 95% confidence interval, 1.04-1.41) compared with those who did not. Women who were randomized to the intervention group also had a significantly lower incidence of cesarean delivery (46.0% vs 55.3%; relative risk, 0.83, 95% confidence interval, 0.71-0.97), maternal discomfort (1.2% vs 9.3%; relative risk, 0.12, 95% confidence interval, 0.02-0.99), and lower pain, assessed by the visual analog scale pain score (mean difference, -4.52 points, 95% confidence interval, -5.35 to 3.69) compared with the control group. The incidences of emergency cesarean delivery (1.6% vs 2.5%; relative risk, 0.63, 95% confidence interval, 0.24-1.70), transient bradycardia (11.8% vs 8.3%; relative risk, 1.42, 95% confidence interval, 0.72-2.80), nonreassuring fetal testing, excluding transient bradycardia, after external cephalic version (6.9% vs 7.4%; relative risk, 0.93, 95% confidence interval, 0.53-1.64), and abruption placentae (0.4% vs 0.4%; relative risk, 1.01, 95% confidence interval, 0.06-16.1) were similar. Administration of neuraxial analgesia significantly increases the success rate of external cephalic version among women with malpresentation at term or late preterm, which then significantly increases the incidence of vaginal delivery. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Fluctuations of the partition function in the generalized random energy model with external field

    NASA Astrophysics Data System (ADS)

    Bovier, Anton; Klimovsky, Anton

    2008-12-01

    We study Derrida's generalized random energy model (GREM) in the presence of uniform external field. We compute the fluctuations of the ground state and of the partition function in the thermodynamic limit for all admissible values of parameters. We find that the fluctuations are described by a hierarchical structure which is obtained by a certain coarse graining of the initial hierarchical structure of the GREM with external field. We provide an explicit formula for the free energy of the model. We also derive some large deviation results providing an expression for the free energy in a class of models with Gaussian Hamiltonians and external field. Finally, we prove that the coarse-grained parts of the system emerging in the thermodynamic limit tend to have a certain optimal magnetization, as prescribed by the strength of the external field and by parameters of the GREM.

  20. 5HTTLPR genotype moderates the longitudinal impact of early caregiving on externalizing behavior

    PubMed Central

    Smyke, Anna T.; Gleason, Mary Margaret; Nelson, Charles A.; Zeanah, Charles H.; Fox, Nathan A; Drury, Stacy S.

    2014-01-01

    We examined caregiver report of externalizing behavior from 12 to 54 months of age in 102 children randomized to care as usual in institutions or to newly-created high quality foster care. At baseline no differences by group or genotype in externalizing were found. However, changes in externalizing from baseline to 42 months of age were moderated by 5HTTLPR genotype and intervention group, where the slope for s/s individuals differed as a function of intervention group. The slope for individuals carrying the l allele did not significantly differ between groups. At 54 months of age, s/s children in the foster care group had the lowest levels of externalizing behavior, while children with the s/s genotype in the care as usual group demonstrated the highest rates of externalizing behavior. No intervention group differences were found in externalizing behavior among children who carried the l allele. These findings, within a randomized control trial of foster care compared to continued care as usual, indicate that 5HTTLPR genotype moderates the relation between early caregiving environments to predict externalizing behavior in children exposed to early institutional care in a manner most consistent with differential susceptibility. PMID:25640827

  1. Behavior Intervention for Students with Externalizing Behavior Problems: Primary-Level Standard Protocol

    ERIC Educational Resources Information Center

    Benner, Gregory J.; Nelson, J. Ron; Sanders, Elizabeth A.; Ralston, Nicole C.

    2012-01-01

    This article examined the efficacy of a primary-level, standard-protocol behavior intervention for students with externalizing behavioral disorders. Elementary schools were randomly assigned to treatment (behavior intervention) or control (business as usual) conditions, and K-3 students were screened for externalizing behavior risk status. The…

  2. Assessing the Generalizability of Randomized Trial Results to Target Populations

    PubMed Central

    Stuart, Elizabeth A.; Bradshaw, Catherine P.; Leaf, Philip J.

    2014-01-01

    Recent years have seen increasing interest in and attention to evidence-based practices, where the “evidence” generally comes from well-conducted randomized trials. However, while those trials yield accurate estimates of the effect of the intervention for the participants in the trial (known as “internal validity”), they do not always yield relevant information about the effects in a particular target population (known as “external validity”). This may be due to a lack of specification of a target population when designing the trial, difficulties recruiting a sample that is representative of a pre-specified target population, or to interest in considering a target population somewhat different from the population directly targeted by the trial. This paper first provides an overview of existing design and analysis methods for assessing and enhancing the ability of a randomized trial to estimate treatment effects in a target population. It then provides a case study using one particular method, which weights the subjects in a randomized trial to match the population on a set of observed characteristics. The case study uses data from a randomized trial of School-wide Positive Behavioral Interventions and Supports (PBIS); our interest is in generalizing the results to the state of Maryland. In the case of PBIS, after weighting, estimated effects in the target population were similar to those observed in the randomized trial. The paper illustrates that statistical methods can be used to assess and enhance the external validity of randomized trials, making the results more applicable to policy and clinical questions. However, there are also many open research questions; future research should focus on questions of treatment effect heterogeneity and further developing these methods for enhancing external validity. Researchers should think carefully about the external validity of randomized trials and be cautious about extrapolating results to specific populations unless they are confident of the similarity between the trial sample and that target population. PMID:25307417

  3. Assessing the generalizability of randomized trial results to target populations.

    PubMed

    Stuart, Elizabeth A; Bradshaw, Catherine P; Leaf, Philip J

    2015-04-01

    Recent years have seen increasing interest in and attention to evidence-based practices, where the "evidence" generally comes from well-conducted randomized trials. However, while those trials yield accurate estimates of the effect of the intervention for the participants in the trial (known as "internal validity"), they do not always yield relevant information about the effects in a particular target population (known as "external validity"). This may be due to a lack of specification of a target population when designing the trial, difficulties recruiting a sample that is representative of a prespecified target population, or to interest in considering a target population somewhat different from the population directly targeted by the trial. This paper first provides an overview of existing design and analysis methods for assessing and enhancing the ability of a randomized trial to estimate treatment effects in a target population. It then provides a case study using one particular method, which weights the subjects in a randomized trial to match the population on a set of observed characteristics. The case study uses data from a randomized trial of school-wide positive behavioral interventions and supports (PBIS); our interest is in generalizing the results to the state of Maryland. In the case of PBIS, after weighting, estimated effects in the target population were similar to those observed in the randomized trial. The paper illustrates that statistical methods can be used to assess and enhance the external validity of randomized trials, making the results more applicable to policy and clinical questions. However, there are also many open research questions; future research should focus on questions of treatment effect heterogeneity and further developing these methods for enhancing external validity. Researchers should think carefully about the external validity of randomized trials and be cautious about extrapolating results to specific populations unless they are confident of the similarity between the trial sample and that target population.

  4. Increased pain relief with remifentanil does not improve the success rate of external cephalic version: a randomized controlled trial.

    PubMed

    Burgos, Jorge; Pijoan, José I; Osuna, Carmen; Cobos, Patricia; Rodriguez, Leire; Centeno, María del Mar; Serna, Rosa; Jimenez, Antonia; Garcia, Eugenia; Fernandez-Llebrez, Luis; Melchor, Juan C

    2016-05-01

    Our objective was to compare the effect of two pain relief methods (remifentanil vs. nitrous oxide) on the success rate of external cephalic version. We conducted a randomized open label parallel-group controlled single-center clinical trial with sequential design, at Cruces University Hospital, Spain. Singleton pregnancies in noncephalic presentation at term that were referred for external cephalic version were assigned according to a balanced (1:1) restricted randomization scheme to analgesic treatment with remifentanil or nitrous oxide during the procedure. The primary endpoint was external cephalic version success rate. Secondary endpoints were adverse event rate, degree of pain, cesarean rate and perinatal outcomes. The trial was stopped early after the second interim analysis due to a very low likelihood of finding substantial differences in efficacy (futility). The external cephalic version success rate was the same in the two arms (31/60, 51.7%) with 120 women recruited, 60 in each arm. The mean pain score was significantly lower in the remifentanil group (3.2 ± 2.4 vs. 6.0 ± 2.3; p < 0.01). No differences were found in external cephalic version-related complications. There was a trend toward a higher frequency of adverse effects in the remifentanil group (18.3% vs. 6.7%, p = 0.10), with a significantly higher incidence rate (21.7 events/100 women vs. 6.7 events/100 women with nitrous oxide, p = 0.03). All reported adverse events were mild and reversible. Remifentanil for analgesia decreased external cephalic version-related pain but did not increase the success rate of external cephalic version at term and appeared to be associated with an increased frequency of mild adverse effects. © 2016 Nordic Federation of Societies of Obstetrics and Gynecology.

  5. Failure and recovery in dynamical networks.

    PubMed

    Böttcher, L; Luković, M; Nagler, J; Havlin, S; Herrmann, H J

    2017-02-03

    Failure, damage spread and recovery crucially underlie many spatially embedded networked systems ranging from transportation structures to the human body. Here we study the interplay between spontaneous damage, induced failure and recovery in both embedded and non-embedded networks. In our model the network's components follow three realistic processes that capture these features: (i) spontaneous failure of a component independent of the neighborhood (internal failure), (ii) failure induced by failed neighboring nodes (external failure) and (iii) spontaneous recovery of a component. We identify a metastable domain in the global network phase diagram spanned by the model's control parameters where dramatic hysteresis effects and random switching between two coexisting states are observed. This dynamics depends on the characteristic link length of the embedded system. For the Euclidean lattice in particular, hysteresis and switching only occur in an extremely narrow region of the parameter space compared to random networks. We develop a unifying theory which links the dynamics of our model to contact processes. Our unifying framework may help to better understand controllability in spatially embedded and random networks where spontaneous recovery of components can mitigate spontaneous failure and damage spread in dynamical networks.

  6. Implementation of client versus care-provider strategies to improve external cephalic version rates: a cluster randomized controlled trial.

    PubMed

    Vlemmix, Floortje; Rosman, Ageeth N; Rijnders, Marlies E; Beuckens, Antje; Opmeer, Brent C; Mol, Ben W J; Kok, Marjolein; Fleuren, Margot A H

    2015-05-01

    To determine the effectiveness of a client or care-provider strategy to improve the implementation of external cephalic version. Cluster randomized controlled trial. Twenty-five clusters; hospitals and their referring midwifery practices randomly selected in the Netherlands. Singleton breech presentation from 32 weeks of gestation onwards. We randomized clusters to a client strategy (written information leaflets and decision aid), a care-provider strategy (1-day counseling course focused on knowledge and counseling skills), a combined client and care-provider strategy and care-as-usual strategy. We performed an intention-to-treat analysis. Rate of external cephalic version in various strategies. Secondary outcomes were the percentage of women counseled and opting for a version attempt. The overall implementation rate of external cephalic version was 72% (1169 of 1613 eligible clients) with a range between clusters of 8-95%. Neither the client strategy (OR 0.8, 95% CI 0.4-1.5) nor the care-provider strategy (OR 1.2, 95% CI 0.6-2.3) showed significant improvements. Results were comparable when we limited the analysis to those women who were actually offered intervention (OR 0.6, 95% CI 0.3-1.4 and OR 2.0, 95% CI 0.7-4.5). Neither a client nor a care-provider strategy improved the external cephalic version implementation rate for breech presentation, neither with regard to the number of version attempts offered nor the number of women accepting the procedure. © 2015 Nordic Federation of Societies of Obstetrics and Gynecology.

  7. Exploring prediction uncertainty of spatial data in geostatistical and machine learning Approaches

    NASA Astrophysics Data System (ADS)

    Klump, J. F.; Fouedjio, F.

    2017-12-01

    Geostatistical methods such as kriging with external drift as well as machine learning techniques such as quantile regression forest have been intensively used for modelling spatial data. In addition to providing predictions for target variables, both approaches are able to deliver a quantification of the uncertainty associated with the prediction at a target location. Geostatistical approaches are, by essence, adequate for providing such prediction uncertainties and their behaviour is well understood. However, they often require significant data pre-processing and rely on assumptions that are rarely met in practice. Machine learning algorithms such as random forest regression, on the other hand, require less data pre-processing and are non-parametric. This makes the application of machine learning algorithms to geostatistical problems an attractive proposition. The objective of this study is to compare kriging with external drift and quantile regression forest with respect to their ability to deliver reliable prediction uncertainties of spatial data. In our comparison we use both simulated and real world datasets. Apart from classical performance indicators, comparisons make use of accuracy plots, probability interval width plots, and the visual examinations of the uncertainty maps provided by the two approaches. By comparing random forest regression to kriging we found that both methods produced comparable maps of estimated values for our variables of interest. However, the measure of uncertainty provided by random forest seems to be quite different to the measure of uncertainty provided by kriging. In particular, the lack of spatial context can give misleading results in areas without ground truth data. These preliminary results raise questions about assessing the risks associated with decisions based on the predictions from geostatistical and machine learning algorithms in a spatial context, e.g. mineral exploration.

  8. The formation of magnetic silicide Fe3Si clusters during ion implantation

    NASA Astrophysics Data System (ADS)

    Balakirev, N.; Zhikharev, V.; Gumarov, G.

    2014-05-01

    A simple two-dimensional model of the formation of magnetic silicide Fe3Si clusters during high-dose Fe ion implantation into silicon has been proposed and the cluster growth process has been computer simulated. The model takes into account the interaction between the cluster magnetization and magnetic moments of Fe atoms random walking in the implanted layer. If the clusters are formed in the presence of the external magnetic field parallel to the implanted layer, the model predicts the elongation of the growing cluster in the field direction. It has been proposed that the cluster elongation results in the uniaxial magnetic anisotropy in the plane of the implanted layer, which is observed in iron silicide films ion-beam synthesized in the external magnetic field.

  9. Serotonin transporter linked polymorphic region (5-HTTLPR) genotype moderates the longitudinal impact of early caregiving on externalizing behavior.

    PubMed

    Brett, Zoë H; Humphreys, Kathryn L; Smyke, Anna T; Gleason, Mary Margaret; Nelson, Charles A; Zeanah, Charles H; Fox, Nathan A; Drury, Stacy S

    2015-02-01

    We examined caregiver report of externalizing behavior from 12 to 54 months of age in 102 children randomized to care as usual in institutions or to newly created high-quality foster care. At baseline no differences by group or genotype in externalizing were found. However, changes in externalizing from baseline to 42 months of age were moderated by the serotonin transporter linked polymorphic region genotype and intervention group, where the slope for short-short (S/S) individuals differed as a function of intervention group. The slope for individuals carrying the long allele did not significantly differ between groups. At 54 months of age, S/S children in the foster care group had the lowest levels of externalizing behavior, while children with the S/S genotype in the care as usual group demonstrated the highest rates of externalizing behavior. No intervention group differences were found in externalizing behavior among children who carried the long allele. These findings, within a randomized controlled trial of foster care compared to continued care as usual, indicate that the serotonin transporter linked polymorphic region genotype moderates the relation between early caregiving environments to predict externalizing behavior in children exposed to early institutional care in a manner most consistent with differential susceptibility.

  10. Diffusion in the presence of a local attracting factor: Theory and interdisciplinary applications.

    PubMed

    Veermäe, Hardi; Patriarca, Marco

    2017-06-01

    In many complex diffusion processes the drift of random walkers is not caused by an external force, as in the case of Brownian motion, but by local variations of fitness perceived by the random walkers. In this paper, a simple but general framework is presented that describes such a type of random motion and may be of relevance in different problems, such as opinion dynamics, cultural spreading, and animal movement. To this aim, we study the problem of a random walker in d dimensions moving in the presence of a local heterogeneous attracting factor expressed in terms of an assigned position-dependent "attractiveness function." At variance with standard Brownian motion, the attractiveness function introduced here regulates both the advection and diffusion of the random walker, thus providing testable predictions for a specific form of fluctuation-relations. We discuss the relation between the drift-diffusion equation based on the attractiveness function and that describing standard Brownian motion, and we provide some explicit examples illustrating its relevance in different fields, such as animal movement, chemotactic diffusion, and social dynamics.

  11. Diffusion in the presence of a local attracting factor: Theory and interdisciplinary applications

    NASA Astrophysics Data System (ADS)

    Veermäe, Hardi; Patriarca, Marco

    2017-06-01

    In many complex diffusion processes the drift of random walkers is not caused by an external force, as in the case of Brownian motion, but by local variations of fitness perceived by the random walkers. In this paper, a simple but general framework is presented that describes such a type of random motion and may be of relevance in different problems, such as opinion dynamics, cultural spreading, and animal movement. To this aim, we study the problem of a random walker in d dimensions moving in the presence of a local heterogeneous attracting factor expressed in terms of an assigned position-dependent "attractiveness function." At variance with standard Brownian motion, the attractiveness function introduced here regulates both the advection and diffusion of the random walker, thus providing testable predictions for a specific form of fluctuation-relations. We discuss the relation between the drift-diffusion equation based on the attractiveness function and that describing standard Brownian motion, and we provide some explicit examples illustrating its relevance in different fields, such as animal movement, chemotactic diffusion, and social dynamics.

  12. A Multilevel AR(1) Model: Allowing for Inter-Individual Differences in Trait-Scores, Inertia, and Innovation Variance.

    PubMed

    Jongerling, Joran; Laurenceau, Jean-Philippe; Hamaker, Ellen L

    2015-01-01

    In this article we consider a multilevel first-order autoregressive [AR(1)] model with random intercepts, random autoregression, and random innovation variance (i.e., the level 1 residual variance). Including random innovation variance is an important extension of the multilevel AR(1) model for two reasons. First, between-person differences in innovation variance are important from a substantive point of view, in that they capture differences in sensitivity and/or exposure to unmeasured internal and external factors that influence the process. Second, using simulation methods we show that modeling the innovation variance as fixed across individuals, when it should be modeled as a random effect, leads to biased parameter estimates. Additionally, we use simulation methods to compare maximum likelihood estimation to Bayesian estimation of the multilevel AR(1) model and investigate the trade-off between the number of individuals and the number of time points. We provide an empirical illustration by applying the extended multilevel AR(1) model to daily positive affect ratings from 89 married women over the course of 42 consecutive days.

  13. Immobilization in External Rotation Versus Internal Rotation After Primary Anterior Shoulder Dislocation: A Meta-analysis of Randomized Controlled Trials.

    PubMed

    Whelan, Daniel B; Kletke, Stephanie N; Schemitsch, Geoffrey; Chahal, Jaskarndip

    2016-02-01

    The recurrence rate after primary anterior shoulder dislocation is high, especially in young, active individuals. Recent studies have suggested external rotation immobilization as a method to reduce the rate of recurrent shoulder dislocation in comparison to traditional sling immobilization. To assess and summarize evidence from randomized controlled trials on the effect of internal rotation versus external rotation immobilization on the rate of recurrence after primary anterior shoulder dislocation. Meta-analysis. PubMed, MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, and abstracts from recent proceedings were searched for eligible studies. Two reviewers selected studies for inclusion, assessed methodological quality, and extracted data. Six randomized controlled trials (632 patients) were included in this review. Demographic and prognostic variables measured at baseline were similar in the pooled groups. The average age was 30.1 years in the pooled external rotation group and 30.3 years in the pooled internal rotation group. Two studies found that external rotation immobilization reduced the rate of recurrence after initial anterior shoulder dislocation compared with conventional internal rotation immobilization, whereas 4 studies failed to find a significant difference between the 2 groups. This meta-analysis suggested no overall significant difference in the rate of recurrence among patients treated with internal rotation versus external rotation immobilization (risk ratio, 0.69; 95% CI, 0.42-1.14; P = .15). There was no significant difference in the rate of compliance between internal and external rotation immobilization (P = .43). The Western Ontario Shoulder Instability Index scores were pooled across 3 studies, and there was no significant difference between the 2 groups (P = .54). Immobilization in external rotation is not significantly more effective in reducing the recurrence rate after primary anterior shoulder dislocation than immobilization in internal rotation. Additionally, this review suggests that there is minimal difference in patients' perceptions of their health-related quality of life after immobilization in internal versus external rotation. © 2015 The Author(s).

  14. A Prospective Randomized Trial to Assess Fixation Strategies for Severe Open Tibia Fractures: Modern Ring External Fixators Versus Internal Fixation (FIXIT Study).

    PubMed

    OʼToole, Robert V; Gary, Joshua L; Reider, Lisa; Bosse, Michael J; Gordon, Wade T; Hutson, James; Quinnan, Stephen M; Castillo, Renan C; Scharfstein, Daniel O; MacKenzie, Ellen J

    2017-04-01

    The treatment of high-energy open tibia fractures is challenging in both the military and civilian environments. Treatment with modern ring external fixation may reduce complications common in these patients. However, no study has rigorously compared outcomes of modern ring external fixation with commonly used internal fixation approaches. The FIXIT study is a prospective, multicenter randomized trial comparing 1-year outcomes after treatment of severe open tibial shaft fractures with modern external ring fixation versus internal fixation among men and women of ages 18-64. The primary outcome is rehospitalization for major limb complications. Secondary outcomes include infection, fracture healing, limb function, and patient-reported outcomes including physical function and pain. One-year treatment costs and patient satisfaction will be compared between the 2 groups, and the percentage of Gustilo IIIB fractures that can be salvaged without soft tissue flap among patients receiving external fixation will be estimated.

  15. The effect of combined stimulation of external cold and vibration during immunization on pain and anxiety levels in children.

    PubMed

    Canbulat Şahiner, Nejla; İnal, Sevil; Sevim Akbay, Ayşe

    2015-06-01

    Procedures involving needles are the most common and major sources of pain in children. External cold and vibration via Buzzy (MMJ Labs, Atlanta, GA) is a method that combines cooling and vibration. This study investigated the effect of the combined stimulation of skin with external cold and vibration via Buzzy on the pain and anxiety levels in children during immunization. This study was a prospective, randomized controlled trial. Children were randomized into two groups: experimental (external cold and Buzzy) and control (no intervention). The pain and anxiety levels of the children were assessed using the Wong-Baker FACES scale and Children Fear Scale. The experimental group showed significantly lower pain and anxiety levels than the control group during immunization. The combined stimulation of skin with external cold and vibration can be used to reduce pain and anxiety during pediatric immunization. Copyright © 2015 American Society of PeriAnesthesia Nurses. Published by Elsevier Inc. All rights reserved.

  16. Influence of radiation on metastability-based TRNG

    NASA Astrophysics Data System (ADS)

    Wieczorek, Piotr Z.; Wieczorek, Zbigniew

    2017-08-01

    This paper presents a True Random Number Generator (TRNG) based on Flip-Flops with violated timing constraints. The proposed circuit has been implemented in a Xilinx Spartan 6 device. The TRNG circuit utilizes the metastability phenomenon as a source of randomness. Therefore, in the paper the influence of timing constraints on the flip-flop metastability proximity is discussed. The metastable range of operation enhances the noise influence on a Flip-Flop behavior. Therefore, the influence of an external stochastic source on the flip-flop operation is also investigated. For this purpose a radioactive source of radiation was used. According to the results shown in the paper the radiation increases the unpredictability of the metastable process of flip-flops operating as the randomness source in the TRNG. The statistical properties of TRNG operating in an increased radiation conditions were verified with the NIST battery of statistical tests.

  17. Stimulus-Dependent State Transition between Synchronized Oscillation and Randomly Repetitive Burst in a Model Cerebellar Granular Layer

    PubMed Central

    Tanaka, Shigeru; Nagao, Soichi; Nishino, Tetsuro

    2011-01-01

    Information processing of the cerebellar granular layer composed of granule and Golgi cells is regarded as an important first step toward the cerebellar computation. Our previous theoretical studies have shown that granule cells can exhibit random alternation between burst and silent modes, which provides a basis of population representation of the passage-of-time (POT) from the onset of external input stimuli. On the other hand, another computational study has reported that granule cells can exhibit synchronized oscillation of activity, as consistent with observed oscillation in local field potential recorded from the granular layer while animals keep still. Here we have a question of whether an identical network model can explain these distinct dynamics. In the present study, we carried out computer simulations based on a spiking network model of the granular layer varying two parameters: the strength of a current injected to granule cells and the concentration of Mg2+ which controls the conductance of NMDA channels assumed on the Golgi cell dendrites. The simulations showed that cells in the granular layer can switch activity states between synchronized oscillation and random burst-silent alternation depending on the two parameters. For higher Mg2+ concentration and a weaker injected current, granule and Golgi cells elicited spikes synchronously (synchronized oscillation state). In contrast, for lower Mg2+ concentration and a stronger injected current, those cells showed the random burst-silent alternation (POT-representing state). It is suggested that NMDA channels on the Golgi cell dendrites play an important role for determining how the granular layer works in response to external input. PMID:21779155

  18. Two Universality Classes for the Many-Body Localization Transition

    NASA Astrophysics Data System (ADS)

    Khemani, Vedika; Sheng, D. N.; Huse, David A.

    2017-08-01

    We provide a systematic comparison of the many-body localization (MBL) transition in spin chains with nonrandom quasiperiodic versus random fields. We find evidence suggesting that these belong to two separate universality classes: the first dominated by "intrinsic" intrasample randomness, and the second dominated by external intersample quenched randomness. We show that the effects of intersample quenched randomness are strongly growing, but not yet dominant, at the system sizes probed by exact-diagonalization studies on random models. Thus, the observed finite-size critical scaling collapses in such studies appear to be in a preasymptotic regime near the nonrandom universality class, but showing signs of the initial crossover towards the external-randomness-dominated universality class. Our results provide an explanation for why exact-diagonalization studies on random models see an apparent scaling near the transition while also obtaining finite-size scaling exponents that strongly violate Harris-Chayes bounds that apply to disorder-driven transitions. We also show that the MBL phase is more stable for the quasiperiodic model as compared to the random one, and the transition in the quasiperiodic model suffers less from certain finite-size effects.

  19. Mechanical Stress Induces Remodeling of Vascular Networks in Growing Leaves

    PubMed Central

    Bar-Sinai, Yohai; Julien, Jean-Daniel; Sharon, Eran; Armon, Shahaf; Nakayama, Naomi; Adda-Bedia, Mokhtar; Boudaoud, Arezki

    2016-01-01

    Differentiation into well-defined patterns and tissue growth are recognized as key processes in organismal development. However, it is unclear whether patterns are passively, homogeneously dilated by growth or whether they remodel during tissue expansion. Leaf vascular networks are well-fitted to investigate this issue, since leaves are approximately two-dimensional and grow manyfold in size. Here we study experimentally and computationally how vein patterns affect growth. We first model the growing vasculature as a network of viscoelastic rods and consider its response to external mechanical stress. We use the so-called texture tensor to quantify the local network geometry and reveal that growth is heterogeneous, resembling non-affine deformations in composite materials. We then apply mechanical forces to growing leaves after veins have differentiated, which respond by anisotropic growth and reorientation of the network in the direction of external stress. External mechanical stress appears to make growth more homogeneous, in contrast with the model with viscoelastic rods. However, we reconcile the model with experimental data by incorporating randomness in rod thickness and a threshold in the rod growth law, making the rods viscoelastoplastic. Altogether, we show that the higher stiffness of veins leads to their reorientation along external forces, along with a reduction in growth heterogeneity. This process may lead to the reinforcement of leaves against mechanical stress. More generally, our work contributes to a framework whereby growth and patterns are coordinated through the differences in mechanical properties between cell types. PMID:27074136

  20. Effect of regional anesthesia on the success rate of external cephalic version: a systematic review and meta-analysis.

    PubMed

    Goetzinger, Katherine R; Harper, Lorie M; Tuuli, Methodius G; Macones, George A; Colditz, Graham A

    2011-11-01

    To estimate whether the use of regional anesthesia is associated with increased success of external cephalic version. We searched MEDLINE, EMBASE, the Cochrane Library, and clinical trial registries. Electronic databases were searched from 1966 through April 2011 for published, randomized controlled trials in the English language comparing regional anesthesia with no regional anesthesia for external cephalic version. The primary outcome was external cephalic version success. Secondary outcomes included cesarean delivery, maternal discomfort, and adverse events. Pooled risk ratios (relative risk) were calculated using a random-effects model. Heterogeneity was assessed using the Cochran's Q statistic and quantified using the I Z method. Six randomized controlled trials met criteria for study inclusion. Regional anesthesia was associated with a higher external cephalic version success rate compared with intravenous or no analgesia (59.7% compared with 37.6%; pooled relative risk 1.58; 95% confidence interval [CI] 1.29-1.93). This significant association persisted when the data were stratified by type of regional anesthesia (spinal compared with epidural). The number needed to treat with regional anesthesia to achieve one additional successful external cephalic version was five. There was no evidence of statistical heterogeneity (P=.32, I Z=14.9%) or publication bias (Harbord test P=.78). There was no statistically significant difference in the risk of cesarean delivery comparing regional anesthesia with intravenous or no analgesia (48.4% compared with 59.3%; pooled relative risk 0.80; 95% CI 0.55-1.17). Adverse events were rare and not significantly different between the two groups. Regional anesthesia is associated with a higher success rate of external cephalic version.

  1. Trajectories of Classroom Externalizing Behavior: Contributions of Child Characteristics, Family Characteristics, and the Teacher-Child Relationship during the School Transition

    ERIC Educational Resources Information Center

    Silver, R.B.; Measelle, J.R.; Armstrong, J.M.; Essex, M.J.

    2005-01-01

    The unique and interactive contributions of past externalizing behavior, negative parenting, and teacher-child relationship quality to externalizing behavior trajectories after the transition to school were examined. In a sample of 283 children, random regression analyses indicated that conflict in the teacher-child relationship during the school…

  2. Random multispace quantization as an analytic mechanism for BioHashing of biometric and random identity inputs.

    PubMed

    Teoh, Andrew B J; Goh, Alwyn; Ngo, David C L

    2006-12-01

    Biometric analysis for identity verification is becoming a widespread reality. Such implementations necessitate large-scale capture and storage of biometric data, which raises serious issues in terms of data privacy and (if such data is compromised) identity theft. These problems stem from the essential permanence of biometric data, which (unlike secret passwords or physical tokens) cannot be refreshed or reissued if compromised. Our previously presented biometric-hash framework prescribes the integration of external (password or token-derived) randomness with user-specific biometrics, resulting in bitstring outputs with security characteristics (i.e., noninvertibility) comparable to cryptographic ciphers or hashes. The resultant BioHashes are hence cancellable, i.e., straightforwardly revoked and reissued (via refreshed password or reissued token) if compromised. BioHashing furthermore enhances recognition effectiveness, which is explained in this paper as arising from the Random Multispace Quantization (RMQ) of biometric and external random inputs.

  3. Noise Enhances Action Potential Generation in Mouse Sensory Neurons via Stochastic Resonance.

    PubMed

    Onorato, Irene; D'Alessandro, Giuseppina; Di Castro, Maria Amalia; Renzi, Massimiliano; Dobrowolny, Gabriella; Musarò, Antonio; Salvetti, Marco; Limatola, Cristina; Crisanti, Andrea; Grassi, Francesca

    2016-01-01

    Noise can enhance perception of tactile and proprioceptive stimuli by stochastic resonance processes. However, the mechanisms underlying this general phenomenon remain to be characterized. Here we studied how externally applied noise influences action potential firing in mouse primary sensory neurons of dorsal root ganglia, modelling a basic process in sensory perception. Since noisy mechanical stimuli may cause stochastic fluctuations in receptor potential, we examined the effects of sub-threshold depolarizing current steps with superimposed random fluctuations. We performed whole cell patch clamp recordings in cultured neurons of mouse dorsal root ganglia. Noise was added either before and during the step, or during the depolarizing step only, to focus onto the specific effects of external noise on action potential generation. In both cases, step + noise stimuli triggered significantly more action potentials than steps alone. The normalized power norm had a clear peak at intermediate noise levels, demonstrating that the phenomenon is driven by stochastic resonance. Spikes evoked in step + noise trials occur earlier and show faster rise time as compared to the occasional ones elicited by steps alone. These data suggest that external noise enhances, via stochastic resonance, the recruitment of transient voltage-gated Na channels, responsible for action potential firing in response to rapid step-wise depolarizing currents.

  4. Noise Enhances Action Potential Generation in Mouse Sensory Neurons via Stochastic Resonance

    PubMed Central

    Onorato, Irene; D'Alessandro, Giuseppina; Di Castro, Maria Amalia; Renzi, Massimiliano; Dobrowolny, Gabriella; Musarò, Antonio; Salvetti, Marco; Limatola, Cristina; Crisanti, Andrea; Grassi, Francesca

    2016-01-01

    Noise can enhance perception of tactile and proprioceptive stimuli by stochastic resonance processes. However, the mechanisms underlying this general phenomenon remain to be characterized. Here we studied how externally applied noise influences action potential firing in mouse primary sensory neurons of dorsal root ganglia, modelling a basic process in sensory perception. Since noisy mechanical stimuli may cause stochastic fluctuations in receptor potential, we examined the effects of sub-threshold depolarizing current steps with superimposed random fluctuations. We performed whole cell patch clamp recordings in cultured neurons of mouse dorsal root ganglia. Noise was added either before and during the step, or during the depolarizing step only, to focus onto the specific effects of external noise on action potential generation. In both cases, step + noise stimuli triggered significantly more action potentials than steps alone. The normalized power norm had a clear peak at intermediate noise levels, demonstrating that the phenomenon is driven by stochastic resonance. Spikes evoked in step + noise trials occur earlier and show faster rise time as compared to the occasional ones elicited by steps alone. These data suggest that external noise enhances, via stochastic resonance, the recruitment of transient voltage-gated Na channels, responsible for action potential firing in response to rapid step-wise depolarizing currents. PMID:27525414

  5. A Free Energy Principle for Biological Systems

    PubMed Central

    Karl, Friston

    2012-01-01

    This paper describes a free energy principle that tries to explain the ability of biological systems to resist a natural tendency to disorder. It appeals to circular causality of the sort found in synergetic formulations of self-organization (e.g., the slaving principle) and models of coupled dynamical systems, using nonlinear Fokker Planck equations. Here, circular causality is induced by separating the states of a random dynamical system into external and internal states, where external states are subject to random fluctuations and internal states are not. This reduces the problem to finding some (deterministic) dynamics of the internal states that ensure the system visits a limited number of external states; in other words, the measure of its (random) attracting set, or the Shannon entropy of the external states is small. We motivate a solution using a principle of least action based on variational free energy (from statistical physics) and establish the conditions under which it is formally equivalent to the information bottleneck method. This approach has proved useful in understanding the functional architecture of the brain. The generality of variational free energy minimisation and corresponding information theoretic formulations may speak to interesting applications beyond the neurosciences; e.g., in molecular or evolutionary biology. PMID:23204829

  6. Chaotic oscillation and random-number generation based on nanoscale optical-energy transfer.

    PubMed

    Naruse, Makoto; Kim, Song-Ju; Aono, Masashi; Hori, Hirokazu; Ohtsu, Motoichi

    2014-08-12

    By using nanoscale energy-transfer dynamics and density matrix formalism, we demonstrate theoretically and numerically that chaotic oscillation and random-number generation occur in a nanoscale system. The physical system consists of a pair of quantum dots (QDs), with one QD smaller than the other, between which energy transfers via optical near-field interactions. When the system is pumped by continuous-wave radiation and incorporates a timing delay between two energy transfers within the system, it emits optical pulses. We refer to such QD pairs as nano-optical pulsers (NOPs). Irradiating an NOP with external periodic optical pulses causes the oscillating frequency of the NOP to synchronize with the external stimulus. We find that chaotic oscillation occurs in the NOP population when they are connected by an external time delay. Moreover, by evaluating the time-domain signals by statistical-test suites, we confirm that the signals are sufficiently random to qualify the system as a random-number generator (RNG). This study reveals that even relatively simple nanodevices that interact locally with each other through optical energy transfer at scales far below the wavelength of irradiating light can exhibit complex oscillatory dynamics. These findings are significant for applications such as ultrasmall RNGs.

  7. Women's experiences of participating in the early external cephalic version 2 trial.

    PubMed

    Murray-Davis, Beth; Marion, Anya; Malott, Anne; Reitsma, Angela; Hutton, Eileen K

    2012-03-01

    The international, multicenter External Cephalic Version 2 (ECV2) Trial compared early external cephalic version at 34(0/7) to 35(6/7) weeks with that at greater than 37 weeks. A total of 1,543 women were randomized from 68 centers in 21 countries. The goal of this component of the trial was to understand women's views about participation in a research trial and timing of external cephalic version. A postpartum questionnaire was completed containing a 5-point Likert scale examining contact and availability of staff, choice of timing of external cephalic version, preference of randomization, convenience of participating, and overall satisfaction. Participants also completed two open-ended questions related to timing of external cephalic version and satisfaction with the trial. Descriptive statistics and content analysis were used to analyze data. A total of 1,458 women completed the questionnaire, of whom 86 percent said "yes"-they would participate in the trial again. Themes influencing decisions about participating were perceptions of the external cephalic version experience, preferred mode of delivery, preferred timing of external cephalic version, and perceptions of the effectiveness of external cephalic version and of the trial environment. Many participants preferred the early timing of the procedure offered through the trial because of perceived advantages of a smaller baby being easier to turn and the opportunity for repeat procedures. Women were positive about their participation in the trial. Early external cephalic version was preferred over the traditional timing as it was perceived to afford both physiologic and practical advantages. © 2012, Copyright the Authors. Journal compilation © 2012, Wiley Periodicals, Inc.

  8. Intravenous nitroglycerin for external cephalic version: a randomized controlled trial.

    PubMed

    Hilton, Jennifer; Allan, Bruce; Swaby, Cheryl; Wahba, Raouf; Wah, Raouf; Jarrell, John; Wood, Stephen; Ross, Sue; Tran, Quynh

    2009-09-01

    To estimate whether treatment with intravenous nitroglycerin for uterine relaxation increases the chance of successful external cephalic version. Two double-blind, randomized clinical trials were undertaken: one in nulliparous women and a second in multiparous women. Women presenting for external cephalic version at term were eligible to participate. The primary outcome was immediate success of external cephalic version. Other outcomes were presentation at delivery, cesarean delivery rate, and side effects and complications. Sample size calculations were based on a 100% increase in success of external cephalic version with a one-sided analysis and alpha=0.05 (80% power). In total, 126 women were recruited-82 in the nulliparous trial and 44 in the multiparous trial. Seven patients did not have external cephalic version before delivery but were included in the analysis of success of external cephalic version. One patient was lost to follow-up. The external cephalic version success rate for nulliparous patients was 24% (10 of 42) in patients who received nitroglycerin compared with 8% (3 of 40) in those who receive placebo (P=.04, one-sided Fisher exact test, odds ratio 3.85, lower bound 1.22). In multiparous patients, the external cephalic version success rate did not differ significantly between groups: 44% (10 of 23) in the nitroglycerin group compared with 43% (9 of 21) in the placebo group (P=.60). Treatment with intravenous nitroglycerin increased the rate of successful external cephalic version in nulliparous, but not in multiparous, women. Treatment with intravenous nitroglycerin appeared to be safe, but our numbers were too small to rule out rare serious adverse effects. I.

  9. Importance of implementing an analytical quality control system in a core laboratory.

    PubMed

    Marques-Garcia, F; Garcia-Codesal, M F; Caro-Narros, M R; Contreras-SanFeliciano, T

    2015-01-01

    The aim of the clinical laboratory is to provide useful information for screening, diagnosis and monitoring of disease. The laboratory should ensure the quality of extra-analytical and analytical process, based on set criteria. To do this, it develops and implements a system of internal quality control, designed to detect errors, and compare its data with other laboratories, through external quality control. In this way it has a tool to detect the fulfillment of the objectives set, and in case of errors, allowing corrective actions to be made, and ensure the reliability of the results. This article sets out to describe the design and implementation of an internal quality control protocol, as well as its periodical assessment intervals (6 months) to determine compliance with pre-determined specifications (Stockholm Consensus(1)). A total of 40 biochemical and 15 immunochemical methods were evaluated using three different control materials. Next, a standard operation procedure was planned to develop a system of internal quality control that included calculating the error of the analytical process, setting quality specifications, and verifying compliance. The quality control data were then statistically depicted as means, standard deviations, and coefficients of variation, as well as systematic, random, and total errors. The quality specifications were then fixed and the operational rules to apply in the analytical process were calculated. Finally, our data were compared with those of other laboratories through an external quality assurance program. The development of an analytical quality control system is a highly structured process. This should be designed to detect errors that compromise the stability of the analytical process. The laboratory should review its quality indicators, systematic, random and total error at regular intervals, in order to ensure that they are meeting pre-determined specifications, and if not, apply the appropriate corrective actions. Copyright © 2015 SECA. Published by Elsevier Espana. All rights reserved.

  10. Interactive learning in 2×2 normal form games by neural network agents

    NASA Astrophysics Data System (ADS)

    Spiliopoulos, Leonidas

    2012-11-01

    This paper models the learning process of populations of randomly rematched tabula rasa neural network (NN) agents playing randomly generated 2×2 normal form games of all strategic classes. This approach has greater external validity than the existing models in the literature, each of which is usually applicable to narrow subsets of classes of games (often a single game) and/or to fixed matching protocols. The learning prowess of NNs with hidden layers was impressive as they learned to play unique pure strategy equilibria with near certainty, adhered to principles of dominance and iterated dominance, and exhibited a preference for risk-dominant equilibria. In contrast, perceptron NNs were found to perform significantly worse than hidden layer NN agents and human subjects in experimental studies.

  11. Sustained Activity in Hierarchical Modular Neural Networks: Self-Organized Criticality and Oscillations

    PubMed Central

    Wang, Sheng-Jun; Hilgetag, Claus C.; Zhou, Changsong

    2010-01-01

    Cerebral cortical brain networks possess a number of conspicuous features of structure and dynamics. First, these networks have an intricate, non-random organization. In particular, they are structured in a hierarchical modular fashion, from large-scale regions of the whole brain, via cortical areas and area subcompartments organized as structural and functional maps to cortical columns, and finally circuits made up of individual neurons. Second, the networks display self-organized sustained activity, which is persistent in the absence of external stimuli. At the systems level, such activity is characterized by complex rhythmical oscillations over a broadband background, while at the cellular level, neuronal discharges have been observed to display avalanches, indicating that cortical networks are at the state of self-organized criticality (SOC). We explored the relationship between hierarchical neural network organization and sustained dynamics using large-scale network modeling. Previously, it was shown that sparse random networks with balanced excitation and inhibition can sustain neural activity without external stimulation. We found that a hierarchical modular architecture can generate sustained activity better than random networks. Moreover, the system can simultaneously support rhythmical oscillations and SOC, which are not present in the respective random networks. The mechanism underlying the sustained activity is that each dense module cannot sustain activity on its own, but displays SOC in the presence of weak perturbations. Therefore, the hierarchical modular networks provide the coupling among subsystems with SOC. These results imply that the hierarchical modular architecture of cortical networks plays an important role in shaping the ongoing spontaneous activity of the brain, potentially allowing the system to take advantage of both the sensitivity of critical states and the predictability and timing of oscillations for efficient information processing. PMID:21852971

  12. Random matrices with external source and the asymptotic behaviour of multiple orthogonal polynomials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aptekarev, Alexander I; Lysov, Vladimir G; Tulyakov, Dmitrii N

    2011-02-28

    Ensembles of random Hermitian matrices with a distribution measure defined by an anharmonic potential perturbed by an external source are considered. The limiting characteristics of the eigenvalue distribution of the matrices in these ensembles are related to the asymptotic behaviour of a certain system of multiple orthogonal polynomials. Strong asymptotic formulae are derived for this system. As a consequence, for matrices in this ensemble the limit mean eigenvalue density is found, and a variational principle is proposed to characterize this density. Bibliography: 35 titles.

  13. Automated external defibrillators and simulated in-hospital cardiac arrests.

    PubMed

    Rossano, Joseph W; Jefferson, Larry S; Smith, E O'Brian; Ward, Mark A; Mott, Antonio R

    2009-05-01

    To test the hypothesis that pediatric residents would have shorter time to attempted defibrillation using automated external defibrillators (AEDs) compared with manual defibrillators (MDs). A prospective, randomized, controlled trial of AEDs versus MDs was performed. Pediatric residents responded to a simulated in-hospital ventricular fibrillation cardiac arrest and were randomized to using either an AED or MD. The primary end point was time to attempted defibrillation. Sixty residents, 21 (35%) interns, were randomized to 2 groups (AED = 30, MD = 30). Residents randomized to the AED group had a significantly shorter time to attempted defibrillation [median, 60 seconds (interquartile range, 53 to 71 seconds)] compared with those randomized to the MD group [median, 103 seconds (interquartile range, 68 to 288 seconds)] (P < .001). All residents in the AED group attempted defibrillation at <5 minutes compared with 23 (77%) in the MD group (P = .01). AEDs improve the time to attempted defibrillation by pediatric residents in simulated cardiac arrests. Further studies are needed to help determine the role of AEDs in pediatric in-hospital cardiac arrests.

  14. Analysis of random signal combinations for spacecraft pointing stability

    NASA Technical Reports Server (NTRS)

    Howell, L.

    1983-01-01

    Methods for obtaining the probability density function of random signal combustions are discussed. These methods provide a realistic criteria for the design of control systems subjected to external noise with several important applications for aerospace problems.

  15. Prediction models for clustered data: comparison of a random intercept and standard regression model

    PubMed Central

    2013-01-01

    Background When study data are clustered, standard regression analysis is considered inappropriate and analytical techniques for clustered data need to be used. For prediction research in which the interest of predictor effects is on the patient level, random effect regression models are probably preferred over standard regression analysis. It is well known that the random effect parameter estimates and the standard logistic regression parameter estimates are different. Here, we compared random effect and standard logistic regression models for their ability to provide accurate predictions. Methods Using an empirical study on 1642 surgical patients at risk of postoperative nausea and vomiting, who were treated by one of 19 anesthesiologists (clusters), we developed prognostic models either with standard or random intercept logistic regression. External validity of these models was assessed in new patients from other anesthesiologists. We supported our results with simulation studies using intra-class correlation coefficients (ICC) of 5%, 15%, or 30%. Standard performance measures and measures adapted for the clustered data structure were estimated. Results The model developed with random effect analysis showed better discrimination than the standard approach, if the cluster effects were used for risk prediction (standard c-index of 0.69 versus 0.66). In the external validation set, both models showed similar discrimination (standard c-index 0.68 versus 0.67). The simulation study confirmed these results. For datasets with a high ICC (≥15%), model calibration was only adequate in external subjects, if the used performance measure assumed the same data structure as the model development method: standard calibration measures showed good calibration for the standard developed model, calibration measures adapting the clustered data structure showed good calibration for the prediction model with random intercept. Conclusion The models with random intercept discriminate better than the standard model only if the cluster effect is used for predictions. The prediction model with random intercept had good calibration within clusters. PMID:23414436

  16. Prediction models for clustered data: comparison of a random intercept and standard regression model.

    PubMed

    Bouwmeester, Walter; Twisk, Jos W R; Kappen, Teus H; van Klei, Wilton A; Moons, Karel G M; Vergouwe, Yvonne

    2013-02-15

    When study data are clustered, standard regression analysis is considered inappropriate and analytical techniques for clustered data need to be used. For prediction research in which the interest of predictor effects is on the patient level, random effect regression models are probably preferred over standard regression analysis. It is well known that the random effect parameter estimates and the standard logistic regression parameter estimates are different. Here, we compared random effect and standard logistic regression models for their ability to provide accurate predictions. Using an empirical study on 1642 surgical patients at risk of postoperative nausea and vomiting, who were treated by one of 19 anesthesiologists (clusters), we developed prognostic models either with standard or random intercept logistic regression. External validity of these models was assessed in new patients from other anesthesiologists. We supported our results with simulation studies using intra-class correlation coefficients (ICC) of 5%, 15%, or 30%. Standard performance measures and measures adapted for the clustered data structure were estimated. The model developed with random effect analysis showed better discrimination than the standard approach, if the cluster effects were used for risk prediction (standard c-index of 0.69 versus 0.66). In the external validation set, both models showed similar discrimination (standard c-index 0.68 versus 0.67). The simulation study confirmed these results. For datasets with a high ICC (≥15%), model calibration was only adequate in external subjects, if the used performance measure assumed the same data structure as the model development method: standard calibration measures showed good calibration for the standard developed model, calibration measures adapting the clustered data structure showed good calibration for the prediction model with random intercept. The models with random intercept discriminate better than the standard model only if the cluster effect is used for predictions. The prediction model with random intercept had good calibration within clusters.

  17. Effect of Intrathecal Bupivacaine Dose on the Success of External Cephalic Version for Breech Presentation: A Prospective, Randomized, Blinded Clinical Trial.

    PubMed

    Chalifoux, Laurie A; Bauchat, Jeanette R; Higgins, Nicole; Toledo, Paloma; Peralta, Feyce M; Farrer, Jason; Gerber, Susan E; McCarthy, Robert J; Sullivan, John T

    2017-10-01

    Breech presentation is a leading cause of cesarean delivery. The use of neuraxial anesthesia increases the success rate of external cephalic version procedures for breech presentation and reduces cesarean delivery rates for fetal malpresentation. Meta-analysis suggests that higher-dose neuraxial techniques increase external cephalic version success to a greater extent than lower-dose techniques, but no randomized study has evaluated the dose-response effect. We hypothesized that increasing the intrathecal bupivacaine dose would be associated with increased external cephalic version success. We conducted a randomized, double-blind trial to assess the effect of four intrathecal bupivacaine doses (2.5, 5.0, 7.5, 10.0 mg) combined with fentanyl 15 μg on the success rate of external cephalic version for breech presentation. Secondary outcomes included mode of delivery, indication for cesarean delivery, and length of stay. A total of 240 subjects were enrolled, and 239 received the intervention. External cephalic version was successful in 123 (51.5%) of 239 patients. Compared with bupivacaine 2.5 mg, the odds (99% CI) for a successful version were 1.0 (0.4 to 2.6), 1.0 (0.4 to 2.7), and 0.9 (0.4 to 2.4) for bupivacaine 5.0, 7.5, and 10.0 mg, respectively (P = 0.99). There were no differences in the cesarean delivery rate (P = 0.76) or indication for cesarean delivery (P = 0.82). Time to discharge was increased 60 min (16 to 116 min) with bupivacaine 7.5 mg or higher as compared with 2.5 mg (P = 0.004). A dose of intrathecal bupivacaine greater than 2.5 mg does not lead to an additional increase in external cephalic procedural success or a reduction in cesarean delivery.

  18. Control of scroll wave turbulence in a three-dimensional reaction-diffusion system with gradient.

    PubMed

    Qiao, Chun; Wu, Yabi; Lu, Xiaochuan; Wang, Chunyan; Ouyang, Qi; Wang, Hongli

    2008-06-01

    In this paper, we summarize our recent experimental and theoretical works on observation and control of scroll wave (SW) turbulence. The experiments were conducted in a three-dimensional Belousov-Zhabotinsky reaction-diffusion system with chemical concentration gradients in one dimension. A spatially homogeneous external forcing was used in the experiments as a control; it was realized by illuminating white light on the light sensitive reaction medium. We observed that, in the oscillatory regime of the system, SW can appear automatically in the gradient system, which will be led to spatiotemporal chaos under certain conditions. A suitable periodic forcing may stabilize inherent turbulence of SW. The mechanism of the transition to SW turbulence is due to the phase twist of SW in the presence of chemical gradients, while modulating the phase twist with a proper periodic forcing can delay this transition. Using the FitzHugh-Nagumo model with an external periodic forcing, we confirmed the control mechanism with numerical simulation. Moreover, we also show in the simulation that adding temporal external noise to the system may have the same control effect. During this process, we observed a new state called "intermittent turbulence," which may undergo a transition into a new type of SW collapse when the noise intensity is further increased. The intermittent state and the collapse could be explained by a random process.

  19. A random utility model of delay discounting and its application to people with externalizing psychopathology.

    PubMed

    Dai, Junyi; Gunn, Rachel L; Gerst, Kyle R; Busemeyer, Jerome R; Finn, Peter R

    2016-10-01

    Previous studies have demonstrated that working memory capacity plays a central role in delay discounting in people with externalizing psychopathology. These studies used a hyperbolic discounting model, and its single parameter-a measure of delay discounting-was estimated using the standard method of searching for indifference points between intertemporal options. However, there are several problems with this approach. First, the deterministic perspective on delay discounting underlying the indifference point method might be inappropriate. Second, the estimation procedure using the R2 measure often leads to poor model fit. Third, when parameters are estimated using indifference points only, much of the information collected in a delay discounting decision task is wasted. To overcome these problems, this article proposes a random utility model of delay discounting. The proposed model has 2 parameters, 1 for delay discounting and 1 for choice variability. It was fit to choice data obtained from a recently published data set using both maximum-likelihood and Bayesian parameter estimation. As in previous studies, the delay discounting parameter was significantly associated with both externalizing problems and working memory capacity. Furthermore, choice variability was also found to be significantly associated with both variables. This finding suggests that randomness in decisions may be a mechanism by which externalizing problems and low working memory capacity are associated with poor decision making. The random utility model thus has the advantage of disclosing the role of choice variability, which had been masked by the traditional deterministic model. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schaefer, Tim; Institut für Physikalische Chemie, Universität zu Köln, 50939 Köln; Schwab, Tobias

    A random scattering approach to enhance light extraction in white top-emitting organic light-emitting diodes (OLEDs) is reported. Through solution processing from fluorinated solvents, a nano-particle scattering layer (NPSL) can be deposited directly on top of small molecule OLEDs without affecting their electrical performance. The scattering length for light inside the NPSL is determined from transmission measurements and found to be in agreement with Mie scattering theory. Furthermore, the dependence of the light outcoupling enhancement on electron transport layer thickness is studied. Depending on the electron transport layer thickness, the NPSL enhances the external quantum efficiency of the investigated white OLEDsmore » by between 1.5 and 2.3-fold. For a device structure that has been optimized prior to application of the NPSL, the maximum external quantum efficiency is improved from 4.7% to 7.4% (1.6-fold improvement). In addition, the scattering layer strongly reduces the undesired shift in emission color with viewing angle.« less

  1. Evaluation of physical activity interventions in children via the reach, efficacy/effectiveness, adoption, implementation, and maintenance (RE-AIM) framework: A systematic review of randomized and non-randomized trials.

    PubMed

    McGoey, Tara; Root, Zach; Bruner, Mark W; Law, Barbi

    2016-01-01

    Existing reviews of physical activity (PA) interventions designed to increase PA behavior exclusively in children (ages 5 to 11years) focus primarily on the efficacy (e.g., internal validity) of the interventions without addressing the applicability of the results in terms of generalizability and translatability (e.g., external validity). This review used the RE-AIM (Reach, Efficacy/Effectiveness, Adoption, Implementation, Maintenance) framework to measure the degree to which randomized and non-randomized PA interventions in children report on internal and external validity factors. A systematic search for controlled interventions conducted within the past 12years identified 78 studies that met the inclusion criteria. Based on the RE-AIM criteria, most of the studies focused on elements of internal validity (e.g., sample size, intervention location and efficacy/effectiveness) with minimal reporting of external validity indicators (e.g., representativeness of participants, start-up costs, protocol fidelity and sustainability). Results of this RE-AIM review emphasize the need for future PA interventions in children to report on real-world challenges and limitations, and to highlight considerations for translating evidence-based results into health promotion practice. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Randomized multicentre trial comparing external and internal pancreatic stenting during pancreaticoduodenectomy.

    PubMed

    Jang, J-Y; Chang, Y R; Kim, S-W; Choi, S H; Park, S J; Lee, S E; Lim, C-S; Kang, M J; Lee, H; Heo, J S

    2016-05-01

    There is no consensus on the best method of preventing postoperative pancreatic fistula (POPF) after pancreaticoduodenectomy (PD). This multicentre, parallel group, randomized equivalence trial investigated the effect of two ways of pancreatic stenting after PD on the rate of POPF. Patients undergoing elective PD or pylorus-preserving PD with duct-to-mucosa pancreaticojejunostomy were enrolled from four tertiary referral hospitals. Randomization was stratified according to surgeon with a 1 : 1 allocation ratio to avoid any related technical factors. The primary endpoint was clinically relevant POPF rate. Secondary endpoints were nutritional index, remnant pancreatic volume, long-term complications and quality of life 2 years after PD. A total of 328 patients were randomized to the external (164 patients) or internal (164) stent group between August 2010 and January 2014. The rates of clinically relevant POPF were 24·4 per cent in the external and 18·9 per cent in the internal stent group (risk difference 5·5 per cent). As the 90 per cent confidence interval (-2·0 to 13·0 per cent) did not fall within the predefined equivalence limits (-10 to 10 per cent), the clinically relevant POPF rates in the two groups were not equivalent. Similar results were observed for patients with soft pancreatic texture and high fistula risk score. Other postoperative outcomes were comparable between the two groups. Five stent-related complications occurred in the external stent group. Multivariable analysis revealed that soft pancreatic texture, non-pancreatic disease and high body mass index (23·3 kg/m 2 or above) predicted clinically relevant POPF. External stenting after PD was associated with a higher rate of clinically relevant POPF than internal stenting. Registration number: NCT01023594 (https://www.clinicaltrials.gov). © 2016 BJS Society Ltd Published by John Wiley & Sons Ltd.

  3. Under What Circumstances Does External Knowledge about the Correlation Structure Improve Power in Cluster Randomized Designs?

    ERIC Educational Resources Information Center

    Rhoads, Christopher

    2014-01-01

    Recent publications have drawn attention to the idea of utilizing prior information about the correlation structure to improve statistical power in cluster randomized experiments. Because power in cluster randomized designs is a function of many different parameters, it has been difficult for applied researchers to discern a simple rule explaining…

  4. Improving Generalizations from Experiments Using Propensity Score Subclassification: Assumptions, Properties, and Contexts

    ERIC Educational Resources Information Center

    Tipton, Elizabeth

    2013-01-01

    As a result of the use of random assignment to treatment, randomized experiments typically have high internal validity. However, units are very rarely randomly selected from a well-defined population of interest into an experiment; this results in low external validity. Under nonrandom sampling, this means that the estimate of the sample average…

  5. Does Fidelity of Implementation Account for Changes in Teacher-Child Interactions in a Randomized Controlled Trial of Banking Time?

    ERIC Educational Resources Information Center

    LoCasale-Crouch, Jennifer; Williford, Amanda; Whittaker, Jessica; DeCoster, Jamie; Alamos, Pilar

    2018-01-01

    This study examined fidelity of implementation in a randomized trial of Banking Time, a classroom-based intervention intended to improve children's behavior, specifically for those at risk for developing externalizing behavior problems, through improving the quality of teacher-child interactions. The study sample comes from a randomized controlled…

  6. Extrapolating Survival from Randomized Trials Using External Data: A Review of Methods

    PubMed Central

    Jackson, Christopher; Stevens, John; Ren, Shijie; Latimer, Nick; Bojke, Laura; Manca, Andrea; Sharples, Linda

    2016-01-01

    This article describes methods used to estimate parameters governing long-term survival, or times to other events, for health economic models. Specifically, the focus is on methods that combine shorter-term individual-level survival data from randomized trials with longer-term external data, thus using the longer-term data to aid extrapolation of the short-term data. This requires assumptions about how trends in survival for each treatment arm will continue after the follow-up period of the trial. Furthermore, using external data requires assumptions about how survival differs between the populations represented by the trial and external data. Study reports from a national health technology assessment program in the United Kingdom were searched, and the findings were combined with “pearl-growing” searches of the academic literature. We categorized the methods that have been used according to the assumptions they made about how the hazards of death vary between the external and internal data and through time, and we discuss the appropriateness of the assumptions in different circumstances. Modeling choices, parameter estimation, and characterization of uncertainty are discussed, and some suggestions for future research priorities in this area are given. PMID:27005519

  7. Syndesmotic fixation in supination-external rotation ankle fractures: a prospective randomized study.

    PubMed

    Pakarinen, Harri J; Flinkkilä, Tapio E; Ohtonen, Pasi P; Hyvönen, Pekka H; Lakovaara, Martti T; Leppilahti, Juhana I; Ristiniemi, Jukka Y

    2011-12-01

    This study was designed to assess whether transfixion of an unstable syndesmosis is necessary in supination-external rotation (Lauge-Hansen SE/Weber B)-type ankle fractures. A prospective study of 140 patients with unilateral Lauge-Hansen supination-external rotation type 4 ankle fractures was done. After bony fixation, the 7.5-Nm standardized external rotation (ER) stress test for both ankles was performed under fluoroscopy. A positive stress examination was defined as a difference of more than 2 mm side-to-side in the tibiotalar or tibiofibular clear spaces on mortise radiographs. If the stress test was positive, the patient was randomized to either syndesmotic transfixion with 3.5-mm tricortical screws or no syndesmotic fixation. Clinical outcome was assessed using the Olerud-Molander scoring system, RAND 36-Item Health Survey, and Visual Analogue Scale (VAS) to measure pain and function after a minimum 1-year of followup. Twenty four (17%) of 140 patients had positive standardized 7.5-Nm ER stress tests after malleolar fixation. The stress view was positive three times on tibiotalar clear space, seven on tibiofibular clear space, and 14 times on both tibiotalar and tibiofibular clear spaces. There was no significant difference between the two randomization groups with regards to Olerud-Molander functional score, VAS scale measuring pain and function, or RAND 36-Item Health Survey pain or physical function at 1 year. Relevant syndesmotic injuries are rare in supination-external rotation ankle fractures, and syndesmotic transfixion with a screw did not influence the functional outcome or pain after the 1-year followup compared with no fixation.

  8. Automated external defibrillation training on the left or the right side - a randomized simulation study.

    PubMed

    Stærk, Mathilde; Bødtker, Henrik; Lauridsen, Kasper G; Løfgren, Bo

    2017-01-01

    Correct placement of the left automated external defibrillator (AED) electrode is rarely achieved. AED electrode placement is predominantly illustrated and trained with the rescuer sitting on the right side of the patient. Placement of the AED electrodes from the left side of the patient may result in a better overview of and access to the left lateral side of the thorax. This study aimed to investigate if training in automated external defibrillation on the left side compared to the right side of a manikin improves left AED electrode placement. Laypeople attending basic life support training were randomized to learn automated external defibrillation from the left or right side of a manikin. After course completion, participants used an AED and placed AED electrodes in a simulated cardiac arrest scenario. In total, 40 laypersons were randomized to AED training on the left (n=19 [missing data =1], 63% female, mean age: 47.3 years) and right (n=20, 75% female, mean age: 48.7 years) sides of a manikin. There was no difference in left AED electrode placement when trained on the left or right side: the mean (SD) distances to the recommended left AED electrode position were 5.9 (2.1) cm vs 6.9 (2.2) cm ( p =0.15) and to the recommended right AED electrode position were 2.6 (1.5) cm vs 1.8 (0.8) cm ( p =0.06), respectively. Training in automated external defibrillation on the left side of a manikin does not improve left AED electrode placement compared to training on the right side.

  9. Fractal attractors in economic growth models with random pollution externalities

    NASA Astrophysics Data System (ADS)

    La Torre, Davide; Marsiglio, Simone; Privileggi, Fabio

    2018-05-01

    We analyze a discrete time two-sector economic growth model where the production technologies in the final and human capital sectors are affected by random shocks both directly (via productivity and factor shares) and indirectly (via a pollution externality). We determine the optimal dynamics in the decentralized economy and show how these dynamics can be described in terms of a two-dimensional affine iterated function system with probability. This allows us to identify a suitable parameter configuration capable of generating exactly the classical Barnsley's fern as the attractor of the log-linearized optimal dynamical system.

  10. Origin and evolution of circular waves and spirals in Dictyostelium discoideum territories.

    PubMed

    Pálsson, E; Cox, E C

    1996-02-06

    Randomly distributed Dictyostelium discoideum cells form cooperative territories by signaling to each other with cAMP. Cells initiate the process by sending out pulsatile signals, which propagate as waves. With time, circular and spiral patterns form. We show that by adding spatial and temporal noise to the levels of an important regulator of external cAMP levels, the cAMP phosphodiesterase inhibitor, we can explain the natural progression of the system from randomly firing cells to circular waves whose symmetries break to form double- and single- or multi-armed spirals. When phosphodiesterase inhibitor is increased with time, mimicking experimental data, the wavelength of the spirals shortens, and a proportion of them evolve into pairs of connected spirals. We compare these results to recent experiments, finding that the temporal and spatial correspondence between experiment and model is very close.

  11. Survival behavior in the cyclic Lotka-Volterra model with a randomly switching reaction rate

    NASA Astrophysics Data System (ADS)

    West, Robert; Mobilia, Mauro; Rucklidge, Alastair M.

    2018-02-01

    We study the influence of a randomly switching reproduction-predation rate on the survival behavior of the nonspatial cyclic Lotka-Volterra model, also known as the zero-sum rock-paper-scissors game, used to metaphorically describe the cyclic competition between three species. In large and finite populations, demographic fluctuations (internal noise) drive two species to extinction in a finite time, while the species with the smallest reproduction-predation rate is the most likely to be the surviving one (law of the weakest). Here we model environmental (external) noise by assuming that the reproduction-predation rate of the strongest species (the fastest to reproduce and predate) in a given static environment randomly switches between two values corresponding to more and less favorable external conditions. We study the joint effect of environmental and demographic noise on the species survival probabilities and on the mean extinction time. In particular, we investigate whether the survival probabilities follow the law of the weakest and analyze their dependence on the external noise intensity and switching rate. Remarkably, when, on average, there is a finite number of switches prior to extinction, the survival probability of the predator of the species whose reaction rate switches typically varies nonmonotonically with the external noise intensity (with optimal survival about a critical noise strength). We also outline the relationship with the case where all reaction rates switch on markedly different time scales.

  12. Application of off-line image processing for optimization in chest computed radiography using a low cost system.

    PubMed

    Muhogora, Wilbroad E; Msaki, Peter; Padovani, Renato

    2015-03-08

     The objective of this study was to improve the visibility of anatomical details by applying off-line postimage processing in chest computed radiography (CR). Four spatial domain-based external image processing techniques were developed by using MATLAB software version 7.0.0.19920 (R14) and image processing tools. The developed techniques were implemented to sample images and their visual appearances confirmed by two consultant radiologists to be clinically adequate. The techniques were then applied to 200 chest clinical images and randomized with other 100 images previously processed online. These 300 images were presented to three experienced radiologists for image quality assessment using standard quality criteria. The mean and ranges of the average scores for three radiologists were characterized for each of the developed technique and imaging system. The Mann-Whitney U-test was used to test the difference of details visibility between the images processed using each of the developed techniques and the corresponding images processed using default algorithms. The results show that the visibility of anatomical features improved significantly (0.005 ≤ p ≤ 0.02) with combinations of intensity values adjustment and/or spatial linear filtering techniques for images acquired using 60 ≤ kVp ≤ 70. However, there was no improvement for images acquired using 102 ≤ kVp ≤ 107 (0.127 ≤ p ≤ 0.48). In conclusion, the use of external image processing for optimization can be effective in chest CR, but should be implemented in consultations with the radiologists.

  13. Application of off‐line image processing for optimization in chest computed radiography using a low cost system

    PubMed Central

    Msaki, Peter; Padovani, Renato

    2015-01-01

    The objective of this study was to improve the visibility of anatomical details by applying off‐line postimage processing in chest computed radiography (CR). Four spatial domain‐based external image processing techniques were developed by using MATLAB software version 7.0.0.19920 (R14) and image processing tools. The developed techniques were implemented to sample images and their visual appearances confirmed by two consultant radiologists to be clinically adequate. The techniques were then applied to 200 chest clinical images and randomized with other 100 images previously processed online. These 300 images were presented to three experienced radiologists for image quality assessment using standard quality criteria. The mean and ranges of the average scores for three radiologists were characterized for each of the developed technique and imaging system. The Mann‐Whitney U‐test was used to test the difference of details visibility between the images processed using each of the developed techniques and the corresponding images processed using default algorithms. The results show that the visibility of anatomical features improved significantly (0.005≤p≤0.02) with combinations of intensity values adjustment and/or spatial linear filtering techniques for images acquired using 60≤kVp≤70. However, there was no improvement for images acquired using 102≤kVp≤107 (0.127≤p≤0.48). In conclusion, the use of external image processing for optimization can be effective in chest CR, but should be implemented in consultations with the radiologists. PACS number: 87.59.−e, 87.59.−B, 87.59.−bd PMID:26103165

  14. Effects of vibration and shock on the performance of gas-bearing space-power Brayton cycle turbomachinery. Part 3: Sinusoidal and random vibration data reduction and evaluation, and random vibration probability analysis

    NASA Technical Reports Server (NTRS)

    Tessarzik, J. M.; Chiang, T.; Badgley, R. H.

    1973-01-01

    The random vibration response of a gas bearing rotor support system has been experimentally and analytically investigated in the amplitude and frequency domains. The NASA Brayton Rotating Unit (BRU), a 36,000 rpm, 10 KWe turbogenerator had previously been subjected in the laboratory to external random vibrations, and the response data recorded on magnetic tape. This data has now been experimentally analyzed for amplitude distribution and magnetic tape. This data has now been experimentally analyzed for amplitude distribution and frequency content. The results of the power spectral density analysis indicate strong vibration responses for the major rotor-bearing system components at frequencies which correspond closely to their resonant frequencies obtained under periodic vibration testing. The results of amplitude analysis indicate an increasing shift towards non-Gaussian distributions as the input level of external vibrations is raised. Analysis of axial random vibration response of the BRU was performed by using a linear three-mass model. Power spectral densities, the root-mean-square value of the thrust bearing surface contact were calculated for specified input random excitation.

  15. The role of fanatics in consensus formation

    NASA Astrophysics Data System (ADS)

    Gündüç, Semra

    2015-08-01

    A model of opinion dynamics with two types of agents as social actors are presented, using the Ising thermodynamic model as the dynamics template. The agents are considered as opportunists which live at sites and interact with the neighbors, or fanatics/missionaries which move from site to site randomly in persuasion of converting agents of opposite opinion with the help of opportunists. Here, the moving agents act as an external influence on the opportunists to convert them to the opposite opinion. It is shown by numerical simulations that such dynamics of opinion formation may explain some details of consensus formation even when one of the opinions are held by a minority. Regardless the distribution of the opinion, different size societies exhibit different opinion formation behavior and time scales. In order to understand general behavior, the scaling relations obtained by comparing opinion formation processes observed in societies with varying population and number of randomly moving agents are studied. For the proposed model two types of scaling relations are observed. In fixed size societies, increasing the number of randomly moving agents give a scaling relation for the time scale of the opinion formation process. The second type of scaling relation is due to the size dependent information propagation in finite but large systems, namely finite-size scaling.

  16. Challenging Students' Intuitions—the Influence of a Tangible Model of Virus Assembly on Students' Conceptual Reasoning About the Process of Self-Assembly

    NASA Astrophysics Data System (ADS)

    Larsson, Caroline; Tibell, Lena A. E.

    2015-10-01

    A well-ordered biological complex can be formed by the random motion of its components, i.e. self-assemble. This is a concept that incorporates issues that may contradict students' everyday experiences and intuitions. In previous studies, we have shown that a tangible model of virus self-assembly, used in a group exercise, helps students to grasp the process of self-assembly and in particular the facet "random molecular collision". The present study investigates how and why the model and the group exercise facilitate students' learning of this particular facet. The data analysed consist of audio recordings of six group exercises ( n = 35 university students) and individual semi-structured interviews ( n = 5 university students). The analysis is based on constructivist perspectives of learning, a combination of conceptual change theory and learning with external representations. Qualitative analysis indicates that perceived counterintuitive aspects of the process created a cognitive conflict within learners. The tangible model used in the group exercises facilitated a conceptual change in their understanding of the process. In particular, the tangible model appeared to provide cues and possible explanations and functioned as an "eye-opener" and a "thinking tool". Lastly, the results show signs of emotions also being important elements for successful accommodation.

  17. Religious belief as compensatory control.

    PubMed

    Kay, Aaron C; Gaucher, Danielle; McGregor, Ian; Nash, Kyle

    2010-02-01

    The authors review experimental evidence that religious conviction can be a defensive source of compensatory control when personal or external sources of control are low. They show evidence that (a) belief in religious deities and secular institutions can serve as external forms of control that can compensate for manipulations that lower personal control and (b) religious conviction can also serve as compensatory personal control after experimental manipulations that lower other forms of personal or external control. The authors review dispositional factors that differentially orient individuals toward external or personal varieties of compensatory control and conclude that compensatory religious conviction can be a flexible source of personal and external control for relief from the anxiety associated with random and uncertain experiences.

  18. Amnioinfusion for women with a singleton breech presentation and a previous failed external cephalic version: a randomized controlled trial.

    PubMed

    Diguisto, Caroline; Winer, Norbert; Descriaud, Celine; Tavernier, Elsa; Weymuller, Victoire; Giraudeau, Bruno; Perrotin, Franck

    2018-04-01

    Our trial aimed to assess the effectiveness of amnioinfusion for a second attempt at external cephalic version (ECV). This open randomized controlled trial was planned with a sequential design. Women at a term ≥36 weeks of gestation with a singleton fetus in breech presentation and a first unsuccessful ECV were recruited in two level-3 maternity units. They were randomly allocated to transabdominal amnioinfusion with a 500-mL saline solution under ultrasound surveillance or no amnioinfusion before the second ECV attempt. Trained senior obstetricians performed all procedures. The primary outcome was the cephalic presentation rate at delivery. Analyses were conducted according to intention to treat (NCT00465712). Recruitment difficulties led to stopping the trial after a 57-month period, 119 women were randomized: 59 allocated to amnioinfusion + ECV and 60 to ECV only. Data were analyzed without applying the sequential feature of the design. The rate of cephalic presentation at delivery did not differ significantly according to whether the second version attempt was or was not preceded by amnioinfusion (20 versus 12%, p = .20). Premature rupture of the membranes occurred for 15% of the women in the amnioinfusion group. Amnioinfusion before a second attempt to external version does not significantly increase the rate of cephalic presentation at delivery.

  19. Geographic Information Systems to Assess External Validity in Randomized Trials.

    PubMed

    Savoca, Margaret R; Ludwig, David A; Jones, Stedman T; Jason Clodfelter, K; Sloop, Joseph B; Bollhalter, Linda Y; Bertoni, Alain G

    2017-08-01

    To support claims that RCTs can reduce health disparities (i.e., are translational), it is imperative that methodologies exist to evaluate the tenability of external validity in RCTs when probabilistic sampling of participants is not employed. Typically, attempts at establishing post hoc external validity are limited to a few comparisons across convenience variables, which must be available in both sample and population. A Type 2 diabetes RCT was used as an example of a method that uses a geographic information system to assess external validity in the absence of a priori probabilistic community-wide diabetes risk sampling strategy. A geographic information system, 2009-2013 county death certificate records, and 2013-2014 electronic medical records were used to identify community-wide diabetes prevalence. Color-coded diabetes density maps provided visual representation of these densities. Chi-square goodness of fit statistic/analysis tested the degree to which distribution of RCT participants varied across density classes compared to what would be expected, given simple random sampling of the county population. Analyses were conducted in 2016. Diabetes prevalence areas as represented by death certificate and electronic medical records were distributed similarly. The simple random sample model was not a good fit for death certificate record (chi-square, 17.63; p=0.0001) and electronic medical record data (chi-square, 28.92; p<0.0001). Generally, RCT participants were oversampled in high-diabetes density areas. Location is a highly reliable "principal variable" associated with health disparities. It serves as a directly measurable proxy for high-risk underserved communities, thus offering an effective and practical approach for examining external validity of RCTs. Copyright © 2017 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  20. Automated external defibrillation training on the left or the right side – a randomized simulation study

    PubMed Central

    Stærk, Mathilde; Bødtker, Henrik; Lauridsen, Kasper G; Løfgren, Bo

    2017-01-01

    Background Correct placement of the left automated external defibrillator (AED) electrode is rarely achieved. AED electrode placement is predominantly illustrated and trained with the rescuer sitting on the right side of the patient. Placement of the AED electrodes from the left side of the patient may result in a better overview of and access to the left lateral side of the thorax. This study aimed to investigate if training in automated external defibrillation on the left side compared to the right side of a manikin improves left AED electrode placement. Methods Laypeople attending basic life support training were randomized to learn automated external defibrillation from the left or right side of a manikin. After course completion, participants used an AED and placed AED electrodes in a simulated cardiac arrest scenario. Results In total, 40 laypersons were randomized to AED training on the left (n=19 [missing data =1], 63% female, mean age: 47.3 years) and right (n=20, 75% female, mean age: 48.7 years) sides of a manikin. There was no difference in left AED electrode placement when trained on the left or right side: the mean (SD) distances to the recommended left AED electrode position were 5.9 (2.1) cm vs 6.9 (2.2) cm (p=0.15) and to the recommended right AED electrode position were 2.6 (1.5) cm vs 1.8 (0.8) cm (p=0.06), respectively. Conclusion Training in automated external defibrillation on the left side of a manikin does not improve left AED electrode placement compared to training on the right side. PMID:29066936

  1. A cross-sectional assessment of the long term effects of brief strategic family therapy for adolescent substance use.

    PubMed

    Horigian, Viviana E; Feaster, Daniel J; Robbins, Michael S; Brincks, Ahnalee M; Ucha, Jessica; Rohrbaugh, Michael J; Shoham, Varda; Bachrach, Ken; Miller, Michael; Burlew, A Kathleen; Hodgkins, Candace C; Carrion, Ibis S; Silverstein, Meredith; Werstlein, Robert; Szapocznik, José

    2015-10-01

    Young adult drug use and law-breaking behaviors often have roots in adolescence. These behaviors are predicted by early drug use, parental substance use disorders, and disrupted and conflict-ridden family environments. To examine long-term outcomes of Brief Strategic Family Therapy (BSFT) compared to treatment as usual (TAU) in the rates of drug use, number of arrests and externalizing behaviors in young adults who were randomized into treatment conditions as adolescents. 261 of 480 adolescents who had been randomized to BSFT or TAU in the BSFT effectiveness study were assessed at a single time, 3-7 years post randomization. Assessments of drug use, externalizing behaviors, arrests and incarcerations were conducted using Timeline Follow Back, Adult Self Report, and self-report, respectively. Drug use, arrests and incarcerations were examined using negative binomial models and externalizing behaviors were examined using linear regression. When compared with TAU, BSFT youth reported lower incidence of lifetime (IRR = 0.68, 95%CI [0.57, 0.81]) and past year (IRR = 0.54, 95%CI [0.40, 0.71]) arrests; lower rates of lifetime (IRR = 0.63, 95%CI [0.49, 0.81]) and past year (IRR = 0.70, 95%CI [0.53, 0.92]) incarcerations; and lower scores on externalizing behaviors at follow-up (B = -0.42, SE = .15, p = .005). There were no differences in drug use. BSFT may have long term effects in reducing the number of arrests, incarcerations and externalizing problems. These effects could be explained by the improvements in family functioning that occurred during the effectiveness study. This study contributes to the literature by reporting on the long term outcomes of family therapy for adolescent drug abuse. © American Academy of Addiction Psychiatry.

  2. External audit of clinical practice and medical decision making in a new Asian oncology center: Results and implications for both developing and developed nations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shakespeare, Thomas P.; Back, Michael F.; Lu, Jiade J.

    2006-03-01

    Purpose: The external audit of oncologist clinical practice is increasingly important because of the incorporation of audits into national maintenance of certification (MOC) programs. However, there are few reports of external audits of oncology practice or decision making. Our institution (The Cancer Institute, Singapore) was asked to externally audit an oncology department in a developing Asian nation, providing a unique opportunity to explore the feasibility of such a process. Methods and Materials: We audited 100 randomly selected patients simulated for radiotherapy in 2003, using a previously reported audit instrument assessing clinical documentation/quality assurance and medical decision making. Results: Clinical documentation/qualitymore » assurance, decision making, and overall performance criteria were adequate 74.4%, 88.3%, and 80.2% of the time, respectively. Overall 52.0% of cases received suboptimal management. Multivariate analysis revealed palliative intent was associated with improved documentation/clinical quality assurance (p = 0.07), decision making (p 0.007), overall performance (p = 0.003), and optimal treatment rates (p 0.07); non-small-cell lung cancer or central nervous system primary sites were associated with better decision making (p = 0.001), overall performance (p = 0.03), and optimal treatment rates (p = 0.002). Conclusions: Despite the poor results, the external audit had several benefits. It identified learning needs for future targeting, and the auditor provided facilitating feedback to address systematic errors identified. Our experience was also helpful in refining our national revalidation audit instrument. The feasibility of the external audit supports the consideration of including audit in national MOC programs.« less

  3. Neuraxial blockade for external cephalic version: a systematic review.

    PubMed

    Sultan, P; Carvalho, B

    2011-10-01

    The desire to decrease the number of cesarean deliveries has renewed interest in external cephalic version. The rationale for using neuraxial blockade to facilitate external cephalic version is to provide abdominal muscular relaxation and reduce patient discomfort during the procedure, so permitting successful repositioning of the fetus to a cephalic presentation. This review systematically examined the current evidence to determine the safety and efficacy of neuraxial anesthesia or analgesia when used for external cephalic version. A systematic literature review of studies that examined success rates of external cephalic version with neuraxial anesthesia was performed. Published articles written in English between 1945 and 2010 were identified using the Medline, Cochrane, EMBASE and Web of Sciences databases. Six, randomized controlled studies were identified. Neuraxial blockade significantly improved the success rate in four of these six studies. A further six non-randomized studies were identified, of which four studies with control groups found that neuraxial blockade increased the success rate of external cephalic version. Despite over 850 patients being included in the 12 studies reviewed, placental abruption was reported in only one patient with a neuraxial block, compared with two in the control groups. The incidence of non-reassuring fetal heart rate requiring cesarean delivery in the anesthesia groups was 0.44% (95% CI 0.15-1.32). Neuraxial blockade improved the likelihood of success during external cephalic version, although the dosing regimen that provides optimal conditions for successful version is unclear. Anesthetic rather than analgesic doses of local anesthetics may improve success. The findings suggest that neuraxial blockade does not compromise maternal or fetal safety during external cephalic version. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  4. Excitonic lasing in solution-processed subwavelength nanosphere assemblies

    DOE PAGES

    Appavoo, Kannatassen; Liu, Xiaoze; Menon, Vinod; ...

    2016-02-03

    Lasing in solution-processed nanomaterials has gained significant interest because of the potential for low-cost integrated photonic devices. Still, a key challenge is to utilize a comprehensive knowledge of the system’s spectral and temporal dynamics to design low-threshold lasing devices. Here, we demonstrate intrinsic lasing (without external cavity) at low-threshold in an ultrathin film of coupled, highly crystalline nanospheres with overall thickness on the order of ~λ/4. The cavity-free geometry consists of ~35 nm zinc oxide nanospheres that collectively localize the in-plane emissive light fields while minimizing scattering losses, resulting in excitonic lasing with fluence thresholds at least an order ofmore » magnitude lower than previous UV-blue random and quantum-dot lasers (<75 μJ/cm 2). Fluence-dependent effects, as quantified by subpicosecond transient spectroscopy, highlight the role of phonon-mediated processes in excitonic lasing. Subpicosecond evolution of distinct lasing modes, together with three-dimensional electromagnetic simulations, indicate a random lasing process, which is in violation of the commonly cited criteria of strong scattering from individual nanostructures and an optically thick sample. Subsequently, an electron–hole plasma mechanism is observed with increased fluence. Furthermore, these results suggest that coupled nanostructures with high crystallinity, fabricated by low-cost solution-processing methods, can function as viable building blocks for high-performance optoelectronics devices.« less

  5. The American Society for Therapeutic Radiology and Oncology (ASTRO) evidence-based review of the role of radiosurgery for malignant glioma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tsao, May N.; Mehta, Minesh P.; Whelan, Timothy J.

    2005-09-01

    Purpose: To systematically review the evidence for the use of stereotactic radiosurgery or stereotactic fractionated radiation therapy in adult patients with malignant glioma. Methods: Key clinical questions to be addressed in this evidence-based review were identified. Outcomes considered were overall survival, quality of life or symptom control, brain tumor control or response and toxicity. MEDLINE (1990-2004 June Week 2), CANCERLIT (1990-2003), CINAHL (1990-2004 June Week 2), EMBASE (1990-2004 Week 25), and the Cochrane library (2004 issue 2) databases were searched using OVID. In addition, the Physician Data Query clinical trials database, the proceedings of the American Society of Clinical Oncologymore » (1997-2004), ASTRO (1997-2004), and the European Society of Therapeutic Radiology and Oncology (ESTRO) (1997-2003) were searched. Data from the literature search were reviewed and tabulated. This process included an assessment of the level of evidence. Results: For patients with newly diagnosed malignant glioma, radiosurgery as boost therapy with conventional external beam radiation was examined in one randomized trial, five prospective cohort studies, and seven retrospective series. There is Level I evidence that the use of radiosurgery boost followed by external beam radiotherapy and carmustine (BCNU) does not confer benefit with respect to overall survival, quality of life, or patterns of failure as compared with external beam radiotherapy and BCNU. There is Level I-III evidence of toxicity associated with radiosurgery boost as compared with external beam radiotherapy alone. The results of the prospective and retrospective studies may be influenced by selection bias. Radiosurgery used as salvage for recurrent or progressive malignant glioma after conventional external beam radiotherapy failure was reported in zero randomized trials, three prospective cohort studies, and five retrospective series. The available data are sparse and insufficient to make absolute recommendations. Stereotactic fractionated radiation therapy has been reported as boost therapy with external beam radiotherapy for patients with newly diagnosed malignant glioma in only three prospective studies. As primary therapy alone without conventional external beam radiotherapy for newly diagnosed malignant glioma patients, stereotactic fractionated radiation therapy has been reported in only one prospective study. There were only three prospective series and two retrospective studies reported for patients with recurrent or progressive malignant glioma. Conclusions: For patients with malignant glioma, there is Level I-III evidence that the use of radiosurgery boost followed by external beam radiotherapy and BCNU does not confer benefit in terms of overall survival, local brain control, or quality of life as compared with external beam radiotherapy and BCNU. The use of radiosurgery boost is associated with increased toxicity. For patients with malignant glioma, there is insufficient evidence regarding the benefits/harms of using radiosurgery at the time progression or recurrence. There is also insufficient evidence regarding the benefits/harms in the use of stereotactic fractionated radiation therapy for patients with newly diagnosed or progressive/recurrent malignant glioma.« less

  6. Factors that influence parental decisions to participate in clinical research: consenters vs nonconsenters.

    PubMed

    Hoberman, Alejandro; Shaikh, Nader; Bhatnagar, Sonika; Haralam, Mary Ann; Kearney, Diana H; Colborn, D Kathleen; Kienholz, Michelle L; Wang, Li; Bunker, Clareann H; Keren, Ron; Carpenter, Myra A; Greenfield, Saul P; Pohl, Hans G; Mathews, Ranjiv; Moxey-Mims, Marva; Chesney, Russell W

    2013-06-01

    A child's health, positive perceptions of the research team and consent process, and altruistic motives play significant roles in the decision-making process for parents who consent for their child to enroll in clinical research. This study identified that nonconsenting parents were better educated, had private insurance, showed lower levels of altruism, and less understanding of study design. To determine the factors associated with parental consent for their child's participation in a randomized, placebo-controlled trial. Cross-sectional survey conducted from July 2008 to May 2011. The survey was an ancillary study to the Randomized Intervention for Children with VesicoUreteral Reflux Study. Seven children's hospitals participating in a randomized trial evaluating management of children with vesicoureteral reflux. Parents asked to provide consent for their child's participation in the randomized trial were invited to complete an anonymous online survey about factors influencing their decision. A total of 120 of the 271 (44%) invited completed the survey; 58 of 125 (46%) who had provided consent and 62 of 144 (43%) who had declined consent completed the survey. A 60-question survey examining child, parent, and study characteristics; parental perception of the study; understanding of the design; external influences; and decision-making process. RESULTS Having graduated from college and private health insurance were associated with a lower likelihood of providing consent. Parents who perceived the trial as having a low degree of risk, resulting in greater benefit to their child and other children, causing little interference with standard care, or exhibiting potential for enhanced care, or who perceived the researcher as professional were significantly more likely to consent to participate. Higher levels of understanding of the randomization process, blinding, and right to withdraw were significantly positively associated with consent to participate. CONCLUSIONS AND RELEVANCE Parents who declined consent had a relatively higher socioeconomic status, had more anxiety about their decision, and found it harder to make their decision compared with consenting parents, who had higher levels of trust and altruism, perceived the potential for enhanced care, reflected better understanding of randomization, and exhibited low decisional uncertainty. Consideration of the factors included in the conceptual model should enhance the quality of the informed consent process and improve participation in pediatric clinical trials.

  7. Why Is Externally-Facilitated Regulated Learning More Effective than Self-Regulated Learning with Hypermedia?

    ERIC Educational Resources Information Center

    Azevedo, Roger; Moos, Daniel C.; Greene, Jeffrey A.; Winters, Fielding I.; Cromley, Jennifer G.

    2008-01-01

    We examined how self-regulated learning (SRL) and externally-facilitated self-regulated learning (ERL) differentially affected adolescents' learning about the circulatory system while using hypermedia. A total of 128 middle-school and high school students with little prior knowledge of the topic were randomly assigned to either the SRL or ERL…

  8. Enhancing Social Inclusion of Children with Externalizing Problems through Classroom Seating Arrangements: A Randomized Controlled Trial

    ERIC Educational Resources Information Center

    van den Berg, Y. H. M.; Stoltz, S.

    2018-01-01

    Inclusive education has brought new challenges for teachers, including the search for a suitable place in the classroom for children with externalizing problems. In the current study, we examined whether a careful rearrangement of the classroom seats could promote social acceptance and more prosocial behaviors for children with externalizing…

  9. The Question of Education Science: "Experiment"ism Versus "Experimental"ism

    ERIC Educational Resources Information Center

    Howe, Kenneth R.

    2005-01-01

    The ascendant view in the current debate about education science -- experimentism -- is a reassertion of the randomized experiment as the methodological gold standard. Advocates of this view have ignored, not answered, long-standing criticisms of the randomized experiment: its frequent impracticality, its lack of external validity, its confinement…

  10. Challenges and Innovations in a Community-Based Participatory Randomized Controlled Trial

    ERIC Educational Resources Information Center

    Goodkind, Jessica R.; Amer, Suha; Christian, Charlisa; Hess, Julia Meredith; Bybee, Deborah; Isakson, Brian L.; Baca, Brandon; Ndayisenga, Martin; Greene, R. Neil; Shantzek, Cece

    2017-01-01

    Randomized controlled trials (RCTs) are a long-standing and important design for conducting rigorous tests of the effectiveness of health interventions. However, many questions have been raised about the external validity of RCTs, their utility in explicating mechanisms of intervention and participants' intervention experiences, and their…

  11. Casimir rack and pinion as a miniaturized kinetic energy harvester

    NASA Astrophysics Data System (ADS)

    Miri, MirFaez; Etesami, Zahra

    2016-08-01

    We study a nanoscale machine composed of a rack and a pinion with no contact, but intermeshed via the lateral Casimir force. We adopt a simple model for the random velocity of the rack subject to external random forces, namely, a dichotomous noise with zero mean value. We show that the pinion, even when it experiences random thermal torque, can do work against a load. The device thus converts the kinetic energy of the random motions of the rack into useful work.

  12. Hybrid time-variant reliability estimation for active control structures under aleatory and epistemic uncertainties

    NASA Astrophysics Data System (ADS)

    Wang, Lei; Xiong, Chuang; Wang, Xiaojun; Li, Yunlong; Xu, Menghui

    2018-04-01

    Considering that multi-source uncertainties from inherent nature as well as the external environment are unavoidable and severely affect the controller performance, the dynamic safety assessment with high confidence is of great significance for scientists and engineers. In view of this, the uncertainty quantification analysis and time-variant reliability estimation corresponding to the closed-loop control problems are conducted in this study under a mixture of random, interval, and convex uncertainties. By combining the state-space transformation and the natural set expansion, the boundary laws of controlled response histories are first confirmed with specific implementation of random items. For nonlinear cases, the collocation set methodology and fourth Rounge-Kutta algorithm are introduced as well. Enlightened by the first-passage model in random process theory as well as by the static probabilistic reliability ideas, a new definition of the hybrid time-variant reliability measurement is provided for the vibration control systems and the related solution details are further expounded. Two engineering examples are eventually presented to demonstrate the validity and applicability of the methodology developed.

  13. Scaling Laws for the Multidimensional Burgers Equation with Quadratic External Potential

    NASA Astrophysics Data System (ADS)

    Leonenko, N. N.; Ruiz-Medina, M. D.

    2006-07-01

    The reordering of the multidimensional exponential quadratic operator in coordinate-momentum space (see X. Wang, C.H. Oh and L.C. Kwek (1998). J. Phys. A.: Math. Gen. 31:4329-4336) is applied to derive an explicit formulation of the solution to the multidimensional heat equation with quadratic external potential and random initial conditions. The solution to the multidimensional Burgers equation with quadratic external potential under Gaussian strongly dependent scenarios is also obtained via the Hopf-Cole transformation. The limiting distributions of scaling solutions to the multidimensional heat and Burgers equations with quadratic external potential are then obtained under such scenarios.

  14. Femoral neck radiography: effect of flexion on visualization.

    PubMed

    Garry, Steven C; Jhangri, Gian S; Lambert, Robert G W

    2005-06-01

    To determine whether flexion improves radiographic visualization of the femoral neck when the femur is externally rotated. Five human femora, with varying neck-shaft and anteversion angles, were measured and immobilized. Degree of flexion required to bring the femoral neck horizontal was measured, varying the rotation. Next, one bone was radiographed in 16 positions, varying rotation in 15 degrees and flexion in 10 degrees increments. Radiographs were presented in randomized blinded fashion to 15 staff radiologists for scoring of femoral neck visualization. Following this, all 5 bones were radiographed in 4 positions of rotation and at 0 degree and 20 degrees flexion, and blinded randomized review of radiographs was repeated. Comparisons between angles and rotations were made using the Mann-Whitney test. The flexion angle required to bring the long axis of the femoral neck horizontal correlated directly with the degree of external rotation (p < 0.05). Visualization of the femoral neck in the extended position progressively deteriorated from 15 degrees internal rotation to 30 degrees external rotation (p < 0.01). However, when 20 degrees flexion was applied to bones in external rotation, visualization significantly improved at 15 degrees (p < 0.05) and 30 degrees (p < 0.01). Flexion of the externally rotated femur can bring the femoral neck into horizontal alignment, and a relatively small amount (20 degrees) of flexion can significantly improve radiographic visualization. This manoeuvre could be useful for radiography of the femoral neck when initial radiographs are inadequate because of external rotation of the leg.

  15. Rational group decision making: A random field Ising model at T = 0

    NASA Astrophysics Data System (ADS)

    Galam, Serge

    1997-02-01

    A modified version of a finite random field Ising ferromagnetic model in an external magnetic field at zero temperature is presented to describe group decision making. Fields may have a non-zero average. A postulate of minimum inter-individual conflicts is assumed. Interactions then produce a group polarization along one very choice which is however randomly selected. A small external social pressure is shown to have a drastic effect on the polarization. Individual bias related to personal backgrounds, cultural values and past experiences are introduced via quenched local competing fields. They are shown to be instrumental in generating a larger spectrum of collective new choices beyond initial ones. In particular, compromise is found to results from the existence of individual competing bias. Conflict is shown to weaken group polarization. The model yields new psychosociological insights about consensus and compromise in groups.

  16. Process evaluation to explore internal and external validity of the "Act in Case of Depression" care program in nursing homes.

    PubMed

    Leontjevas, Ruslan; Gerritsen, Debby L; Koopmans, Raymond T C M; Smalbrugge, Martin; Vernooij-Dassen, Myrra J F J

    2012-06-01

    A multidisciplinary, evidence-based care program to improve the management of depression in nursing home residents was implemented and tested using a stepped-wedge design in 23 nursing homes (NHs): "Act in case of Depression" (AiD). Before effect analyses, to evaluate AiD process data on sampling quality (recruitment and randomization, reach) and intervention quality (relevance and feasibility, extent to which AiD was performed), which can be used for understanding internal and external validity. In this article, a model is presented that divides process evaluation data into first- and second-order process data. Qualitative and quantitative data based on personal files of residents, interviews of nursing home professionals, and a research database were analyzed according to the following process evaluation components: sampling quality and intervention quality. Nursing home. The pattern of residents' informed consent rates differed for dementia special care units and somatic units during the study. The nursing home staff was satisfied with the AiD program and reported that the program was feasible and relevant. With the exception of the first screening step (nursing staff members using a short observer-based depression scale), AiD components were not performed fully by NH staff as prescribed in the AiD protocol. Although NH staff found the program relevant and feasible and was satisfied with the program content, individual AiD components may have different feasibility. The results on sampling quality implied that statistical analyses of AiD effectiveness should account for the type of unit, whereas the findings on intervention quality implied that, next to the type of unit, analyses should account for the extent to which individual AiD program components were performed. In general, our first-order process data evaluation confirmed internal and external validity of the AiD trial, and this evaluation enabled further statistical fine tuning. The importance of evaluating the first-order process data before executing statistical effect analyses is thus underlined. Copyright © 2012 American Medical Directors Association, Inc. Published by Elsevier Inc. All rights reserved.

  17. Syntactic sequencing in Hebbian cell assemblies.

    PubMed

    Wennekers, Thomas; Palm, Günther

    2009-12-01

    Hebbian cell assemblies provide a theoretical framework for the modeling of cognitive processes that grounds them in the underlying physiological neural circuits. Recently we have presented an extension of cell assemblies by operational components which allows to model aspects of language, rules, and complex behaviour. In the present work we study the generation of syntactic sequences using operational cell assemblies timed by unspecific trigger signals. Syntactic patterns are implemented in terms of hetero-associative transition graphs in attractor networks which cause a directed flow of activity through the neural state space. We provide regimes for parameters that enable an unspecific excitatory control signal to switch reliably between attractors in accordance with the implemented syntactic rules. If several target attractors are possible in a given state, noise in the system in conjunction with a winner-takes-all mechanism can randomly choose a target. Disambiguation can also be guided by context signals or specific additional external signals. Given a permanently elevated level of external excitation the model can enter an autonomous mode, where it generates temporal grammatical patterns continuously.

  18. An on-line calibration algorithm for external parameters of visual system based on binocular stereo cameras

    NASA Astrophysics Data System (ADS)

    Wang, Liqiang; Liu, Zhen; Zhang, Zhonghua

    2014-11-01

    Stereo vision is the key in the visual measurement, robot vision, and autonomous navigation. Before performing the system of stereo vision, it needs to calibrate the intrinsic parameters for each camera and the external parameters of the system. In engineering, the intrinsic parameters remain unchanged after calibrating cameras, and the positional relationship between the cameras could be changed because of vibration, knocks and pressures in the vicinity of the railway or motor workshops. Especially for large baselines, even minute changes in translation or rotation can affect the epipolar geometry and scene triangulation to such a degree that visual system becomes disabled. A technology including both real-time examination and on-line recalibration for the external parameters of stereo system becomes particularly important. This paper presents an on-line method for checking and recalibrating the positional relationship between stereo cameras. In epipolar geometry, the external parameters of cameras can be obtained by factorization of the fundamental matrix. Thus, it offers a method to calculate the external camera parameters without any special targets. If the intrinsic camera parameters are known, the external parameters of system can be calculated via a number of random matched points. The process is: (i) estimating the fundamental matrix via the feature point correspondences; (ii) computing the essential matrix from the fundamental matrix; (iii) obtaining the external parameters by decomposition of the essential matrix. In the step of computing the fundamental matrix, the traditional methods are sensitive to noise and cannot ensure the estimation accuracy. We consider the feature distribution situation in the actual scene images and introduce a regional weighted normalization algorithm to improve accuracy of the fundamental matrix estimation. In contrast to traditional algorithms, experiments on simulated data prove that the method improves estimation robustness and accuracy of the fundamental matrix. Finally, we take an experiment for computing the relationship of a pair of stereo cameras to demonstrate accurate performance of the algorithm.

  19. Is the internal connection more efficient than external connection in mechanical, biological, and esthetical point of views? A systematic review.

    PubMed

    Goiato, Marcelo Coelho; Pellizzer, Eduardo Piza; da Silva, Emily Vivianne Freitas; Bonatto, Liliane da Rocha; dos Santos, Daniela Micheline

    2015-09-01

    This systematic review aimed to evaluate if the internal connection is more efficient than the external connection and its associated influencing factors. A specific question was formulated according to the Population, Intervention, Control, and Outcome (PICO): Is internal connection more efficient than external connection in mechanical, biological, and esthetical point of views? An electronic search of the MEDLINE and the Web of Knowledge databases was performed for relevant studies published in English up to November 2013 by two independent reviewers. The keywords used in the search included a combination of "dental implant" and "internal connection" or "Morse connection" or "external connection." Selected studies were randomized clinical trials, prospective or retrospective studies, and in vitro studies with a clear aim of investigating the internal and/or external implant connection use. From an initial screening yield of 674 articles, 64 potentially relevant articles were selected after an evaluation of their titles and abstracts. Full texts of these articles were obtained with 29 articles fulfilling the inclusion criteria. Morse taper connection has the best sealing ability. Concerning crestal bone loss, internal connections presented better results than external connections. The limitation of the present study was the absence of randomized clinical trials that investigated if the internal connection was more efficient than the external connection. The external and internal connections have different mechanical, biological, and esthetical characteristics. Besides all systems that show proper success rates and effectiveness, crestal bone level maintenance is more important around internal connections than external connections. The Morse taper connection seems to be more efficient concerning biological aspects, allowing lower bacterial leakage and bone loss in single implants, including aesthetic regions. Additionally, this connection type can be successfully indicated for fixed partial prostheses and overdenture planning, since it exhibits high mechanical stability.

  20. Can Genetics Predict Response to Complex Behavioral Interventions? Evidence from a Genetic Analysis of the Fast Track Randomized Control Trial

    PubMed Central

    Albert, Dustin; Belsky, Daniel W.; Crowley, D. Max; Latendresse, Shawn J.; Aliev, Fazil; Riley, Brien; Sun, Cuie; Dick, Danielle M.; Dodge, Kenneth R.

    2014-01-01

    Early interventions are a preferred method for addressing behavioral problems in high-risk children, but often have only modest effects. Identifying sources of variation in intervention effects can suggest means to improve efficiency. One potential source of such variation is the genome. We conducted a genetic analysis of the Fast Track Randomized Control Trial, a 10-year-long intervention to prevent high-risk kindergarteners from developing adult externalizing problems including substance abuse and antisocial behavior. We tested whether variants of the glucocorticoid receptor gene NR3C1 were associated with differences in response to the Fast Track intervention. We found that in European-American children, a variant of NR3C1 identified by the single-nucleotide polymorphism rs10482672 was associated with increased risk for externalizing psychopathology in control group children and decreased risk for externalizing psychopathology in intervention group children. Variation in NR3C1 measured in this study was not associated with differential intervention response in African-American children. We discuss implications for efforts to prevent externalizing problems in high-risk children and for public policy in the genomic era. PMID:26106668

  1. Data requirements for valuing externalities: The role of existing permitting processes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lee, A.D.; Baechler, M.C.; Callaway, J.M.

    1990-08-01

    While the assessment of externalities, or residual impacts, will place new demands on regulators, utilities, and developers, existing processes already require certain data and information that may fulfill some of the data needs for externality valuation. This paper examines existing siting, permitting, and other processes and highlights similarities and differences between their data requirements and the data required to value environmental externalities. It specifically considers existing requirements for siting new electricity resources in Oregon and compares them with the information and data needed to value externalities for such resources. This paper also presents several observations about how states can takemore » advantage of data acquired through processes already in place as they move into an era when externalities are considered in utility decision-making. It presents other observations on the similarities and differences between the data requirements under existing processes and those for valuing externalities. This paper also briefly discusses the special case of cumulative impacts. And it presents recommendations on what steps to take in future efforts to value externalities. 35 refs., 2 tabs.« less

  2. Using an Experimental Medicine Model to Explore Combination Effects of Pharmacological and Cognitive Interventions for Depression and Anxiety

    PubMed Central

    Browning, Michael; Grol, Maud; Ly, Verena; Goodwin, Guy M; Holmes, Emily A; Harmer, Catherine J

    2011-01-01

    Selective serotonergic reuptake inhibitors (SSRIs) and cognitive therapies are effective in the treatment of anxiety and depression. Previous research suggests that both forms of treatments may work by altering cognitive biases in the processing of affective information. The current study assessed the effects of combining an SSRI with a cognitive intervention on measures of affective processing bias and resilience to external challenge. A total of 62 healthy participants were randomly assigned to receive either 7 days of citalopram (20 mg) or placebo capsules while also completing either an active or a control version of a computerized cognitive bias training task. After treatment, standard measures of affective processing bias were collected. Participants' resilience to external stress was also tested by measuring the increase in negative symptoms induced by a negative mood induction. Participants who received both citalopram and the active cognitive bias training task showed a smaller alteration in emotional memory and categorization bias than did those who received either active intervention singly. The degree to which memory for negative information was altered by citalopram predicted participants' resistance to the negative mood induction. These results suggest that co-administration of an SSRI and a cognitive training intervention can reduce the effectiveness of either treatment alone in terms of anxiety- and depression-relevant emotional processing. More generally, the findings suggest that pinpointing the cognitive actions of treatments may inform future development of combination strategies in mental health. PMID:21832988

  3. Assessment of generalizability, applicability and predictability (GAP) for evaluating external validity in studies of universal family-based prevention of alcohol misuse in young people: systematic methodological review of randomized controlled trials.

    PubMed

    Fernandez-Hermida, Jose Ramon; Calafat, Amador; Becoña, Elisardo; Tsertsvadze, Alexander; Foxcroft, David R

    2012-09-01

    To assess external validity characteristics of studies from two Cochrane Systematic Reviews of the effectiveness of universal family-based prevention of alcohol misuse in young people. Two reviewers used an a priori developed external validity rating form and independently assessed three external validity dimensions of generalizability, applicability and predictability (GAP) in randomized controlled trials. The majority (69%) of the included 29 studies were rated 'unclear' on the reporting of sufficient information for judging generalizability from sample to study population. Ten studies (35%) were rated 'unclear' on the reporting of sufficient information for judging applicability to other populations and settings. No study provided an assessment of the validity of the trial end-point measures for subsequent mortality, morbidity, quality of life or other economic or social outcomes. Similarly, no study reported on the validity of surrogate measures using established criteria for assessing surrogate end-points. Studies evaluating the benefits of family-based prevention of alcohol misuse in young people are generally inadequate at reporting information relevant to generalizability of the findings or implications for health or social outcomes. Researchers, study authors, peer reviewers, journal editors and scientific societies should take steps to improve the reporting of information relevant to external validity in prevention trials. © 2012 The Authors. Addiction © 2012 Society for the Study of Addiction.

  4. Prospective randomized comparison of mitomycin C application in endoscopic and external dacryocystorhinostomy.

    PubMed

    Mudhol, Rekha R; Zingade, N D; Mudhol, R S; Harugop, Anil S; Das, Amal T

    2013-08-01

    The aim of the study is to compare the subjective (relief of symptoms) and objective (endoscopic visualization of ostium patency at the time of syringing) outcomes at the end of two procedures-Endonasal DCR versus External DCR with Mitomycin C and to assess the role of Mitomycin C in maintaining patency of nasolacrimal drainage system. Prospective randomized comparative study was performed. Thirty-five patients were enrolled in each endoscopic and external dacryocystorhinostomy groups with Mitomycin C (MMC) application. The 37 eyes underwent endonasal DCR (28 unilateral primary eyes + 1 bilateral primary eyes + 5 unilateral revision eyes + 1 bilateral revision eye) while 35 eyes underwent external DCR (34 unilateral primary eyes + 1 unilateral revision eye). Mitomycin C 0.2 mg/ml was applied intra-operatively for 5 min to the ostium site at the end of endonasal or external DCR procedure. Objective assessment by syringing at the end of 1 year in the endonasal group showed 35 eyes (94%) were patent, 1 (3%) was partially blocked and 1(3%) was completely blocked; while in external group all 35 eyes (100%) were patent. Endoscopic visualization of the ostium at the time of syringing showed only one eye (3%) in the endonasal group was blocked while all the other eyes in both groups were patent. Both groups had a mean follow-up of 6-36 months. No complications were associated with use of Mitomycin C. In conclusion, intra-operative use of Mitomycin C in both endoscopic DCR and external DCR is safe and effective in increasing the success rate.

  5. Remifentanil versus placebo for analgesia during external cephalic version: a randomised clinical trial.

    PubMed

    Muñoz, H; Guerra, S; Perez-Vaquero, P; Valero Martinez, C; Aizpuru, F; Lopez-Picado, A

    2014-02-01

    Breech presentation occurs in up to 3% of pregnancies at term and may be an indication for caesarean delivery. External cephalic version can be effective in repositioning the fetus in a cephalic presentation, but may be painful for the mother. Our aim was to assess the efficacy of remifentanil versus placebo for pain relief during external cephalic version. A randomized, double-blind, controlled trial that included women at 36-41 weeks of gestation with non-cephalic presentations was performed. Women were randomized to receive either a remifentanil infusion at 0.1 μg/kg/min and demand boluses of 0.1 μg/kg, or saline placebo. The primary outcome was the numerical rating pain score (0-10) after external cephalic version. Sixty women were recruited, 29 in the control group and 31 in the remifentanil group. There were significant differences in pain scores at the end of the procedure (control 6.5 ± 2.4 vs. remifentanil 4.7 ± 2.5, P = 0.005) but not 10 min later (P = 0.054). The overall success rate for external cephalic version was 49% with no significant differences between groups (remifentanil group 54.8% vs. control group 41.3%, P = 0.358). In the remifentanil group, there was one case of nausea and vomiting, one of drowsiness and three cases of fetal bradycardia. In the control group, there were three cases of nausea and vomiting, one of dizziness and nine cases of fetal bradycardia. Intravenous remifentanil with bolus doses on demand during external cephalic version achieved a reduction in pain and increased maternal satisfaction. There were no additional adverse effects, and no difference in the success rate of external cephalic version or the incidence of fetal bradycardia. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Lessons learned from a single institution's retrospective analysis of emergent cesarean delivery following external cephalic version with and without neuraxial anesthesia.

    PubMed

    Ainsworth, A; Sviggum, H P; Tolcher, M C; Weaver, A L; Holman, M A; Arendt, K W

    2017-05-01

    To evaluate the risk of emergent cesarean delivery with the use of neuraxial anesthesia for external cephalic version in a single practice. Randomized trials have shown increased external cephalic version success when neuraxial anesthesia is used, without additional risk. We hypothesized that in our actual clinical practice, outside the confines of randomized trials, neuraxial anesthesia could be associated with an increased risk of emergent cesarean delivery. This retrospective cohort study included all women who underwent external cephalic version at a single institution with and without neuraxial anesthesia. The primary outcome was the incidence of emergent cesarean delivery (defined as delivery within 4hours of version). Secondary outcomes were version success and ultimate mode of delivery. A total of 135 women underwent external cephalic version procedures; 58 with neuraxial anesthesia (43.0%) and 77 without (57.0%). Location of the procedure, tocolytic therapy, and gestational age were different between groups. An increased rate of emergent cesarean delivery was found in procedures with neuraxial anesthesia compared to procedures without (5/58 (8.6%) compared to 0/77 (0.0%); 95% CI for difference, 1.4 to 15.8%; P=0.013). In this single hospital's practice, patients who may be at higher risk of complications and have a lesser likelihood of success were provided NA for ECV. As a result, the use of neuraxial anesthesia for external cephalic version was associated with a higher rate of emergent cesarean delivery. Obstetric and anesthetic practices should evaluate their patient selection and procedure protocol for external cephalic version under neuraxial anesthesia. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. External validation of the Society of Thoracic Surgeons General Thoracic Surgery Database.

    PubMed

    Magee, Mitchell J; Wright, Cameron D; McDonald, Donna; Fernandez, Felix G; Kozower, Benjamin D

    2013-11-01

    The Society of Thoracic Surgeons (STS) General Thoracic Surgery Database (GTSD) reports outstanding results for lung and esophageal cancer resection. However, a major weakness of the GTSD has been the lack of validation of this voluntary registry. The purpose of this study was to perform an external, independent audit to assess the accuracy of the data collection process and the quality of the database. An independent firm was contracted to audit 5% of sites randomly selected from the GTDB in 2011. Audits were performed remotely to maximize the number of audits performed and reduce cost. Auditors compared lobectomy cases submitted to the GTSD with the hospital operative logs to evaluate completeness of the data. In addition, 20 lobectomy records from each site were audited in detail. Agreement rates were calculated for 32 individual data elements, 7 data categories pertaining to patient status or care delivery, and an overall agreement rate for each site. Six process variables were also evaluated to assess best practice for data collection and submission. Ten sites were audited from the 222 participants. Comparison of the 559 submitted lobectomy cases with operative logs from each site identified 28 omissions, a 94.6% agreement rate (discrepancies/site range, 2 to 27). Importantly, cases not submitted had no mortality or major morbidity, indicating a lack of purposeful omission. The aggregate agreement rates for all categories were greater than 90%. The overall data accuracy was 94.9%. External audits of the GTSD validate the accuracy and completeness of the data. Careful examination of unreported cases demonstrated no purposeful omission or gaming. Although these preliminary results are quite good, it is imperative that the audit process is refined and continues to expand along with the GTSD to insure reliability of the database. The audit results are currently being incorporated into educational and quality improvement processes to add further value. Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  8. The electron-spin--nuclear-spin interaction studied by polarized neutron scattering.

    PubMed

    Stuhrmann, Heinrich B

    2007-11-01

    Dynamic nuclear spin polarization (DNP) is mediated by the dipolar interaction of paramagnetic centres with nuclear spins. This process is most likely to occur near paramagnetic centres at an angle close to 45 degrees with respect to the direction of the external magnetic field. The resulting distribution of polarized nuclear spins leads to an anisotropy of the polarized neutron scattering pattern, even with randomly oriented radical molecules. The corresponding cross section of polarized coherent neutron scattering in terms of a multipole expansion is derived for radical molecules in solution. An application using data of time-resolved polarized neutron scattering from an organic chromium(V) molecule is tested.

  9. Entropic forces in Brownian motion

    NASA Astrophysics Data System (ADS)

    Roos, Nico

    2014-12-01

    Interest in the concept of entropic forces has risen considerably since Verlinde proposed in 2011 to interpret the force in Newton's second law and gravity as entropic forces. Brownian motion—the motion of a small particle (pollen) driven by random impulses from the surrounding molecules—may be the first example of a stochastic process in which such forces are expected to emerge. In this article, it is shown that at least two types of entropic force can be identified in three-dimensional Brownian motion. This analysis yields simple derivations of known results of Brownian motion, Hooke's law, and—applying an external (non-radial) force—Curie's law and the Langevin-Debye equation.

  10. Parent-child relationship quality and family transmission of parent posttraumatic stress disorder symptoms and child externalizing and internalizing symptoms following fathers' exposure to combat trauma.

    PubMed

    Snyder, James; Gewirtz, Abigail; Schrepferman, Lynn; Gird, Suzanne R; Quattlebaum, Jamie; Pauldine, Michael R; Elish, Katie; Zamir, Osnat; Hayes, Charles

    2016-11-01

    Transactional cascades among child internalizing and externalizing symptoms, and fathers' and mothers' posttraumatic stress disorder (PTSD) symptoms were examined in a sample of families with a male parent who had been deployed to recent military conflicts in the Middle East. The role of parents' positive engagement and coercive interaction with their child, and family members' emotion regulation were tested as processes linking cascades of parent and child symptoms. A subsample of 183 families with deployed fathers and nondeployed mothers and their 4- to 13-year-old children who participated in a randomized control trial intervention (After Deployment: Adaptive Parenting Tools) were assessed at baseline prior to intervention, and at 12 and 24 months after baseline, using parent reports of their own and their child's symptoms. Parents' observed behavior during interaction with their children was coded using a multimethod approach at each assessment point. Reciprocal cascades among fathers' and mothers' PTSD symptoms, and child internalizing and externalizing symptoms, were observed. Fathers' and mothers' positive engagement during parent-child interaction linked their PTSD symptoms and their child's internalizing symptoms. Fathers' and mothers' coercive behavior toward their child linked their PTSD symptoms and their child's externalizing symptoms. Each family member's capacity for emotion regulation was associated with his or her adjustment problems at baseline. Implications for intervention, and for research using longitudinal models and a family-systems perspective of co-occurrence and cascades of symptoms across family members are described.

  11. Reducing and preventing internalizing and externalizing behavior problems in children with type 1 diabetes: a randomized controlled trial of the Triple P-Positive Parenting Program.

    PubMed

    Westrupp, E M; Northam, E; Lee, K J; Scratch, S E; Cameron, F

    2015-11-01

    Children with type 1 diabetes are at increased risk of mental health problems, which in turn are associated with poor glycemic control, diabetes-related complications, and long-term psychiatric morbidity. We tested the efficacy of the Triple P-Positive Parenting Program in reducing or preventing mental health problems and improving glycemic control in children with type 1 diabetes in a randomized controlled trial. Participants were recruited from the Diabetes Clinic, Royal Children's Hospital, Melbourne, Australia, and randomized to Triple P or standard diabetes care. The primary outcome was child internalizing and externalizing behavior problems 3 and 12 months postrandomization. Secondary outcomes were glycemic control, parent mental health, parenting skills, and family functioning at 3 and 12 months, and glycemic control at 24 months. A total of 76 participants were randomized (38 to intervention and 38 to control), 60 completed 3-month, and 57 completed 12-month assessments. Benefits of Triple P were evident at 3 months for parent mental health, parenting skills, and family functioning (p < 0.05), but not for child mental health or glycemic control, with little effect at 12 months. Prespecified subgroup analyses for children with pre-existing internalizing or externalizing behavior problems indicated greater improvements in child mental health, parent mental health, parenting skills, and diabetes family conflict (p < 0.05), but lower parenting self-efficacy at 3 months. Improvements in parent mental health and parenting competency associated with Triple P were sustained to 12 months for children with pre-existing mental health problems. This study provides some support for the efficacy of Triple P in improving parent and family outcomes, and reducing child internalizing and externalizing behavior problems primarily in children who have pre-existing mental health problems. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Training the Antifragile Athlete: A Preliminary Analysis of Neuromuscular Training Effects on Muscle Activation Dynamics.

    PubMed

    Kiefer, Adam W; Myer, Gregory D

    2015-10-01

    Athletic injuries typically occur when the stable, emergent coordination between behavioral processes breaks down due to external noise, or variability. A physiological system that operates at an optimal point on a spectrum of rigidity and flexibility may be better prepared to handle extreme external variability, and the purpose of the current experiment was to examine whether targeted neuromuscular training resulted in changes to the rigidity and flexibility of the gluteal muscle tonus signal as measured with electromyography prior to the landing phase of a drop vertical jump task. 10 adolescent female athletes who participated in a targeted 10-week neuromuscular training program and 6 controls participated, and their tonus dynamics were examined with recurrence quantification analysis prior to training and after the 10-week program. The dependent measures, percent laminarity (%LAM) and percent determinism (%DET) were hypothesized to decrease following training, and were submitted to a one tailed mixed-model ANOVA. The training group exhibited a decrease in %LAM and %DET after training compared to pre-training and controls. The present findings indicate increased metaflexibility (i.e., greater intermittency and an increase in internal randomness) in tonus dynamics following neuromuscular training, and have important implications for the prevention of musculoskeletal injury in sport, specifically within the context of external noise and antifragility.

  13. Inspiratory muscle training in patients with chronic obstructive pulmonary disease: structural adaptation and physiologic outcomes.

    PubMed

    Ramirez-Sarmiento, Alba; Orozco-Levi, Mauricio; Guell, Rosa; Barreiro, Esther; Hernandez, Nuria; Mota, Susana; Sangenis, Merce; Broquetas, Joan M; Casan, Pere; Gea, Joaquim

    2002-12-01

    The present study was aimed at evaluating the effects of a specific inspiratory muscle training protocol on the structure of inspiratory muscles in patients with chronic obstructive pulmonary disease. Fourteen patients (males, FEV1, 24 +/- 7% predicted) were randomized to either inspiratory muscle or sham training groups. Supervised breathing using a threshold inspiratory device was performed 30 minutes per day, five times a week, for 5 consecutive weeks. The inspiratory training group was subjected to inspiratory loading equivalent to 40 to 50% of their maximal inspiratory pressure. Biopsies from external intercostal muscles and vastus lateralis (control muscle) were taken before and after the training period. Muscle samples were processed for morphometric analyses using monoclonal antibodies against myosin heavy chain isoforms I and II. Increases in both the strength and endurance of the inspiratory muscles were observed in the inspiratory training group. This improvement was associated with increases in the proportion of type I fibers (by approximately 38%, p < 0.05) and in the size of type II fibers (by approximately 21%, p < 0.05) in the external intercostal muscles. No changes were observed in the control muscle. The study demonstrates that inspiratory training induces a specific functional improvement of the inspiratory muscles and adaptive changes in the structure of external intercostal muscles.

  14. Improving LADCP Velocity Profiles with External Attitude Sensors

    NASA Astrophysics Data System (ADS)

    Thurnherr, A. M.; Goszczko, I.

    2016-12-01

    Data collected with Acoustic Doppler Current Profilers installed on CTD rosettes and lowered through the water column (LADCP systems) are routinely used to derive full-depth profiles of ocean velocity. In addition to the uncertainties arising from random noise in the along-beam velocity measurements, LADCP derived velocities are commonly contaminated by bias errors due to imperfectly measured instrument attitude (pitch, roll and heading). Of particular concern are the heading measurements because it is not usually feasible to calibrate the internal ADCP compasses with the instruments installed on a CTD rosette, away from the magnetic disturbances of the ship as well as the current-carrying winch wire. Heading data from dual-headed LADCP systems, which consist of upward and downward-pointing ADCPs installed on the same rosette, commonly indicate heading-dependent compass errors with amplitudes exceeding 10 degrees. In an attempt to reduce LADCP velocity errors, over 200 full-depth profiles were collected during several recent projects, including GO-SHIP, DIMES and ECOGIG, with an inexpensive (<$200) external magnetometer/accelerometer package. The resulting data permit full compass calibrations (for both hard- and soft-iron effects) from in-situ profile data and yields improved pitch and roll measurements. Results indicate greatly reduced inconsistencies between the data from the two ADCPs (horizontal-velocity processing residuals), as well as smaller biases in vertical -velocity (w) measurements. In addition, the external magnetometer package allows processing of some LADCP data collected in regions where the horizontal magnitude of the earth's magnetic field is insufficient for the ADCPs internal compasses to work at all.

  15. Use of 3D Printed Models in Medical Education: A Randomized Control Trial Comparing 3D Prints versus Cadaveric Materials for Learning External Cardiac Anatomy

    ERIC Educational Resources Information Center

    Lim, Kah Heng Alexander; Loo, Zhou Yaw; Goldie, Stephen J.; Adams, Justin W.; McMenamin, Paul G.

    2016-01-01

    Three-dimensional (3D) printing is an emerging technology capable of readily producing accurate anatomical models, however, evidence for the use of 3D prints in medical education remains limited. A study was performed to assess their effectiveness against cadaveric materials for learning external cardiac anatomy. A double blind randomized…

  16. Internal versus external motivation in referral of primary care patients with depression to an internet support group: randomized controlled trial.

    PubMed

    Van Voorhees, Benjamin W; Hsiung, Robert C; Marko-Holguin, Monika; Houston, Thomas K; Fogel, Joshua; Lee, Royce; Ford, Daniel E

    2013-03-12

    Depressive disorders and symptoms affect more than one-third of primary care patients, many of whom do not receive or do not complete treatment. Internet-based social support from peers could sustain depression treatment engagement and adherence. We do not know whether primary care patients will accept referral to such websites nor do we know which methods of referral would be most effective. We conducted a randomized clinical trial to determine whether (1) a simple generic referral card (control), (2) a patient-oriented brochure that provided examples of online postings and experience (internal motivation), or (3) a physician letter of recommendation (external motivation) would generate the greatest participation in a primary care Internet depression treatment support portal focused around an Internet support group (ISG). We used 3 offline methods to identify potential participants who had not used an ISG in the past 6 months. Eligibility was determined in part by a brief structured psychiatric interview based on the Patient Health Questionnaire-9 (PHQ-9). After consent and enrollment, participants were randomly assigned to 1 of 3 groups (control, internal motivation, or external motivation). We constructed a portal to connect primary care patients to both fact-based information and an established ISG (Psycho-Babble). The ISG allowed participants to view messages and then decide if they actually wished to register there. Participation in the portal and the ISG was assessed via automated activity tracking. Fifty participants were assigned to the 3 groups: a motivation-neutral control group (n=18), an internal motivation group (n=19), and an external motivation group (n=13). Of these participants, 31 (62%) visited the portal; 27 (54%) visited the ISG itself. The internal motivation group showed significantly greater participation than the control group on several measures. The external motivation group spent significantly less time logged onto the portal than the control group. The internal motivation group showed significantly greater participation than the external motivation group on several measures. Referral of primary care patients with depressive disorders and symptoms to an ISG is feasible even if they have never previously used one. This may best be accomplished by enhancing their internal motivation.

  17. Persistent fluctuations in synchronization rate in globally coupled oscillators with periodic external forcing

    NASA Astrophysics Data System (ADS)

    Atsumi, Yu; Nakao, Hiroya

    2012-05-01

    A system of phase oscillators with repulsive global coupling and periodic external forcing undergoing asynchronous rotation is considered. The synchronization rate of the system can exhibit persistent fluctuations depending on parameters and initial phase distributions, and the amplitude of the fluctuations scales with the system size for uniformly random initial phase distributions. Using the Watanabe-Strogatz transformation that reduces the original system to low-dimensional macroscopic equations, we show that the fluctuations are collective dynamics of the system corresponding to low-dimensional trajectories of the reduced equations. It is argued that the amplitude of the fluctuations is determined by the inhomogeneity of the initial phase distribution, resulting in system-size scaling for the random case.

  18. Cognitive Behavioral Principles Within Group Mentoring: A Randomized Pilot Study

    PubMed Central

    JENT, JASON F.; NIEC, LARISSA N.

    2010-01-01

    This study evaluated the effectiveness of a group mentoring program that included components of empirically supported mentoring and cognitive behavioral techniques for children served at a community mental health center. Eighty-six 8- to 12-year-old children were randomly assigned to either group mentoring or a wait-list control group. Group mentoring significantly increased children’s reported social problem-solving skills and decreased parent-reported child externalizing and internalizing behavior problems after controlling for other concurrent mental health services. Attrition from the group mentoring program was notably low (7%) for children. The integration of a cognitive behavioral group mentoring program into children’s existing community mental health services may result in additional reductions in externalizing and internalizing behavior problems. PMID:20582243

  19. STS-114: Discovery Tanking Operations for Launch

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Jessica Rye from NASA Public Affairs is the narrator for the tanking operations for the launch of the Space Shuttle Discovery. She presents a video of the arrival and processing of the new external tank at the Kennedy Space Center. The external tank is also shown entering the Vehicle Assembly Building (VAB). The external tank underwent new processing resulting from its redesign including inspection of the bipod heater and the external separation camera. The changes to the external tank include: 1) Electric heaters to protect from icing; and 2) Liquid Oxygen feed line bellows to carry fuel from the external tank to the Orbiter. Footage of the external tank processing facility at NASA's Michoud Assembly Facility in New Orleans, La. prior to its arrival at Kennedy Space Center is shown and a video of the three key modifications to the external tank including the bipod, flange and bellows are shown.

  20. Apparatus for measuring surface movement of an object that is subjected to external vibrations

    DOEpatents

    Kotidis, Petros A.; Woodroffe, Jaime A.; Rostler, Peter S.

    1997-01-01

    A system for non-destructively measuring an object and controlling industrial processes in response to the measurement is disclosed in which an impulse laser generates a plurality of sound waves over timed increments in an object. A polarizing interferometer is used to measure surface movement of the object caused by the sound waves and sensed by phase shifts in the signal beam. A photon multiplier senses the phase shift and develops an electrical signal. A signal conditioning arrangement modifies the electrical signals to generate an average signal correlated to the sound waves which in turn is correlated to a physical or metallurgical property of the object, such as temperature, which property may then be used to control the process. External, random vibrations of the workpiece are utilized to develop discernible signals which can be sensed in the interferometer by only one photon multiplier. In addition the interferometer includes an arrangement for optimizing its sensitivity so that movement attributed to various waves can be detected in opaque objects. The interferometer also includes a mechanism for sensing objects with rough surfaces which produce speckle light patterns. Finally the interferometer per se, with the addition of a second photon multiplier is capable of accurately recording beam length distance differences with only one reading.

  1. Method and apparatus for measuring surface movement of a solid object that is subjected to external vibrations

    DOEpatents

    Schultz, Thomas J.; Kotidis, Petros A.; Woodroffe, Jaime A.; Rostler, Peter S.

    1995-01-01

    A system for non-destructively measuring an object and controlling industrial processes in response to the measurement is disclosed in which an impulse laser generates a plurality of sound waves over timed increments in an object. A polarizing interferometer is used to measure surface movement of the object caused by the sound waves and sensed by phase shifts in the signal beam. A photon multiplier senses the phase shift and develops an electrical signal. A signal conditioning arrangement modifies the electrical signals to generate an average signal correlated to the sound waves which in turn is correlated to a physical or metallurgical property of the object, such as temperature, which property may then be used to control the process. External, random vibrations of the workpiece are utilized to develop discernible signals which can be sensed in the interferometer by only one photon multiplier. In addition the interferometer includes an arrangement for optimizing its sensitivity so that movement attributed to various waves can be detected in opaque objects. The interferometer also includes a mechanism for sensing objects with rough surfaces which produce speckle light patterns. Finally the interferometer per se, with the addition of a second photon multiplier is capable of accurately recording beam length distance differences with only one reading.

  2. Method and apparatus for measuring surface movement of a solid object that is subjected to external vibrations

    DOEpatents

    Schultz, T.J.; Kotidis, P.A.; Woodroffe, J.A.; Rostler, P.S.

    1995-04-25

    A system for non-destructively measuring an object and controlling industrial processes in response to the measurement is disclosed in which an impulse laser generates a plurality of sound waves over timed increments in an object. A polarizing interferometer is used to measure surface movement of the object caused by the sound waves and sensed by phase shifts in the signal beam. A photon multiplier senses the phase shift and develops an electrical signal. A signal conditioning arrangement modifies the electrical signals to generate an average signal correlated to the sound waves which in turn is correlated to a physical or metallurgical property of the object, such as temperature, which property may then be used to control the process. External, random vibrations of the workpiece are utilized to develop discernible signals which can be sensed in the interferometer by only one photon multiplier. In addition the interferometer includes an arrangement for optimizing its sensitivity so that movement attributed to various waves can be detected in opaque objects. The interferometer also includes a mechanism for sensing objects with rough surfaces which produce speckle light patterns. Finally the interferometer per se, with the addition of a second photon multiplier is capable of accurately recording beam length distance differences with only one reading. 38 figs.

  3. Apparatus for measuring surface movement of an object that is subjected to external vibrations

    DOEpatents

    Kotidis, P.A.; Woodroffe, J.A.; Rostler, P.S.

    1997-04-22

    A system for non-destructively measuring an object and controlling industrial processes in response to the measurement is disclosed in which an impulse laser generates a plurality of sound waves over timed increments in an object. A polarizing interferometer is used to measure surface movement of the object caused by the sound waves and sensed by phase shifts in the signal beam. A photon multiplier senses the phase shift and develops an electrical signal. A signal conditioning arrangement modifies the electrical signals to generate an average signal correlated to the sound waves which in turn is correlated to a physical or metallurgical property of the object, such as temperature, which property may then be used to control the process. External, random vibrations of the workpiece are utilized to develop discernible signals which can be sensed in the interferometer by only one photon multiplier. In addition the interferometer includes an arrangement for optimizing its sensitivity so that movement attributed to various waves can be detected in opaque objects. The interferometer also includes a mechanism for sensing objects with rough surfaces which produce speckle light patterns. Finally the interferometer per se, with the addition of a second photon multiplier is capable of accurately recording beam length distance differences with only one reading. 38 figs.

  4. The quality of care in occupational therapy: an assessment of selected Michigan hospitals.

    PubMed

    Kirchman, M M

    1979-07-01

    In this study, a methodology was developed and tested for assessing the quality of care in occupational therapy between educational and noneducational clinical settings, as measured by process and outcome. An instrument was constructed for an external audit of the hospital record. Standards drafted by the investigator were established as normative by a panel of experts for use in judging the programs. Hospital records of 84 patients with residual hemiparesis or hemiplegia in three noneducational settings and of 100 patients with similar diagnoses in two educational clinical settings from selected Michigan facilities were chosen by proportionate stratified random sampling. The process study showed that occupational therapy was of significantly higher quality in the educational settings. The outcome study did not show significant differences between types of settings. Implications for education and practice are discussed.

  5. Long-term effects of a universal family intervention: mediation through parent-adolescent conflict.

    PubMed

    Jensen, Michaeline R; Wong, Jessie J; Gonzales, Nancy A; Dumka, Larry E; Millsap, Roger; Coxe, Stefany

    2014-01-01

    This randomized trial of a family-focused preventive intervention for Mexican American middle schoolers examined internalizing, externalizing, and substance use outcomes in late adolescence, 5 years after completing the intervention. Parent-adolescent conflict was tested as a mediator of these effects. The role of parent and adolescent acculturation in these pathways was also examined. There were 494 seventh-grade adolescents and their primary female caregivers randomized to receive either a 9-week multicomponent intervention or a brief workshop control group. Assessments were conducted at pretest, 2-year follow-up (9th grade), and 5-year follow-up (when most participants were in the 12th grade). The Bridges program significantly reduced mother-adolescent conflict measured in the 9th grade, with conflict mediating program effects on internalizing and externalizing symptoms, adolescent substance use, and diagnosed internalizing disorder in late adolescence. Mother and child acculturation were both significantly predictive of late adolescence outcomes. Contrary to hypotheses, neither mother nor child acculturation emerged as a significant predictor of mother-adolescent conflict, and the interaction of mother and adolescent acculturation was similarly not related to mother-adolescent conflict. Intervention effects were largely consistent across different levels of acculturation. These findings provide support for the efficacy of family-focused intervention during early adolescence, both in reducing mental health problems and substance use in the long term and in impacting parent-adolescent conflict processes that appear to play an important role in the development of later adjustment problems.

  6. Hydrodynamic interactions induce movement against an external load in a ratchet dimer Brownian motor.

    PubMed

    Fornés, José A

    2010-01-15

    We use the Brownian dynamics with hydrodynamic interactions simulation in order to describe the movement of a elastically coupled dimer Brownian motor in a ratchet potential. The only external forces considered in our system were the load, the random thermal noise and an unbiased thermal fluctuation. For a given set of parameters we observe direct movement against the load force if hydrodynamic interactions were considered.

  7. Perception of Students on Causes of Poor Performance in Chemistry in External Examinations in Umuahia North Local Government of Abia State

    ERIC Educational Resources Information Center

    Ojukwu, M. O.

    2016-01-01

    The aim of this study was to investigate the perception of students on the causes of their poor performance in external chemistry examinations in Umuahia North Local Government Area of Abia State. Descriptive survey design was used for the study. Two hundred and forty (240) students were selected through simple random sampling for the study. A…

  8. Flight Dynamic Simulation of Fighter In the Asymmetric External Store Release Process

    NASA Astrophysics Data System (ADS)

    Safi’i, Imam; Arifianto, Ony; Nurohman, Chandra

    2018-04-01

    In the fighter design, it is important to evaluate and analyze the flight dynamic of the aircraft earlier in the development process. One of the case is the dynamics of external store release process. A simulation tool can be used to analyze the fighter/external store system’s dynamics in the preliminary design stage. This paper reports the flight dynamics of Jet Fighter Experiment (JF-1 E) in asymmetric Advance Medium Range Air to Air Missile (AMRAAM) release process through simulations. The JF-1 E and AIM 120 AMRAAAM models are built by using Advanced Aircraft Analysis (AAA) and Missile Datcom software. By using these softwares, the aerodynamic stability and control derivatives can be obtained and used to model the dynamic characteristic of the fighter and the external store. The dynamic system is modeled by using MATLAB/Simulink software. By using this software, both the fighter/external store integration and the external store release process is simulated, and the dynamic of the system can be analyzed.

  9. The Effects of Different External Carbon Sources on Nitrous Oxide Emissions during Denitrification in Biological Nutrient Removal Processes

    NASA Astrophysics Data System (ADS)

    Hu, Xiang; Zhang, Jing; Hou, Hongxun

    2018-01-01

    The aim of this study was to investigate the effects of two different external carbon sources (acetate and ethanol) on the nitrous oxide (N2O) emissions during denitrification in biological nutrient removal processes. Results showed that external carbon source significantly influenced N2O emissions during the denitrification process. When acetate served as the external carbon source, 0.49 mg N/L and 0.85 mg N/L of N2O was produced during the denitrificaiton processes in anoxic and anaerobic/anoxic experiments, giving a ratio of N2O-N production to TN removal of 2.37% and 4.96%, respectively. Compared with acetate, the amount of N2O production is negligible when ethanol used as external carbon addition. This suggested that ethanol is a potential alternative external carbon source for acetate from the point of view of N2O emissions.

  10. Clinical Applications of Stochastic Dynamic Models of the Brain, Part I: A Primer.

    PubMed

    Roberts, James A; Friston, Karl J; Breakspear, Michael

    2017-04-01

    Biological phenomena arise through interactions between an organism's intrinsic dynamics and stochastic forces-random fluctuations due to external inputs, thermal energy, or other exogenous influences. Dynamic processes in the brain derive from neurophysiology and anatomical connectivity; stochastic effects arise through sensory fluctuations, brainstem discharges, and random microscopic states such as thermal noise. The dynamic evolution of systems composed of both dynamic and random effects can be studied with stochastic dynamic models (SDMs). This article, Part I of a two-part series, offers a primer of SDMs and their application to large-scale neural systems in health and disease. The companion article, Part II, reviews the application of SDMs to brain disorders. SDMs generate a distribution of dynamic states, which (we argue) represent ideal candidates for modeling how the brain represents states of the world. When augmented with variational methods for model inversion, SDMs represent a powerful means of inferring neuronal dynamics from functional neuroimaging data in health and disease. Together with deeper theoretical considerations, this work suggests that SDMs will play a unique and influential role in computational psychiatry, unifying empirical observations with models of perception and behavior. Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  11. Non-Randomized Studies as a Source of Complementary, Sequential or Replacement Evidence for Randomized Controlled Trials in Systematic Reviews on the Effects of Interventions

    ERIC Educational Resources Information Center

    Schünemann, Holger J.; Tugwell, Peter; Reeves, Barnaby C.; Akl, Elie A.; Santesso, Nancy; Spencer, Frederick A.; Shea, Beverley; Wells, George; Helfand, Mark

    2013-01-01

    The terms applicability, generalizability, external validity and transferability are related, sometimes used interchangeably and have in common that they lack a clear and consistent definition in the classic epidemiological literature. However, all of these terms generally describe one overarching theme: whether or not available research evidence…

  12. Random preferences towards bioenergy environmental externalities: a case study of woody biomass based electricity in the Southern United States

    Treesearch

    Andres Susaeta; Pankaj Lal; Janaki Alavalapati; Evan Mercer

    2011-01-01

    This paper contrasts alternate methodological approaches of investigating public preferences, the random parameter logit (RPL) where tastes and preferences of respondents are assumed to be heterogeneous and the conditional logit (CL) approach where tastes and preferences remain fixed for individuals. We conducted a choice experiment to assess preferences for woody...

  13. Explanatory Versus Pragmatic Trials: An Essential Concept in Study Design and Interpretation.

    PubMed

    Merali, Zamir; Wilson, Jefferson R

    2017-11-01

    Randomized clinical trials often represent the highest level of clinical evidence available to evaluate the efficacy of an intervention in clinical medicine. Although the process of randomization serves to maximize internal validity, the external validity, or generalizability, of such studies depends on several factors determined at the design phase of the trial including eligibility criteria, study setting, and outcomes of interest. In general, explanatory trials are optimized to demonstrate the efficacy of an intervention in a highly selected patient group; however, findings from these studies may not be generalizable to the larger clinical problem. In contrast, pragmatic trials attempt to understand the real-world benefit of an intervention by incorporating design elements that allow for greater generalizability and clinical applicability of study results. In this article we describe the explanatory-pragmatic continuum for clinical trials in greater detail. Further, a well-accepted tool for grading trials on this continuum is described, and applied, to 2 recently published trials pertaining to the surgical management of lumbar degenerative spondylolisthesis.

  14. Effect of internal versus external focus of attention on implicit motor learning in children with developmental coordination disorder.

    PubMed

    Jarus, Tal; Ghanouni, Parisa; Abel, Rachel L; Fomenoff, Shelby L; Lundberg, Jocelyn; Davidson, Stephanie; Caswell, Sarah; Bickerton, Laura; Zwicker, Jill G

    2015-02-01

    Children with developmental coordination disorder (DCD) struggle to learn new motor skills. It is unknown whether children with DCD learn motor skills more effectively with an external focus of attention (focusing on impact of movement on the environment) or an internal focus of attention (focusing on one's body movements) during implicit (unconscious) and explicit (conscious) motor learning. This paper aims to determine the trends of implicit motor learning in children with DCD, and how focus of attention influences motor learning in children with DCD in comparison with typically developing children. 25 children, aged 8-12, with (n=12) and without (n=13) DCD were randomly assigned to receive instructions that focused attention externally or internally while completing a computer tracking task during acquisition, retention, and transfer phases. The motor task involved tracking both repeated and random patterns, with the repeated pattern indicative of implicit learning. Children with DCD scored lower on the motor task in all three phases of the study, demonstrating poorer implicit learning. Furthermore, graphical data showed that for the children with DCD, there was no apparent difference between internal and external focus of attention during retention and transfer, while there was an advantage to the external focus of attention group for typically developing children. Children with DCD demonstrate less accuracy than typically developing children in learning a motor task. Also, the effect of focus of attention on motor performance is different in children with DCD versus their typically developing counterparts during the three phases of motor learning. Results may inform clinicians how to facilitate motor learning in children with DCD by incorporating explicit learning with either internal or external focus of attention within interventions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Accounting for center in the Early External Cephalic Version trials: an empirical comparison of statistical methods to adjust for center in a multicenter trial with binary outcomes.

    PubMed

    Reitsma, Angela; Chu, Rong; Thorpe, Julia; McDonald, Sarah; Thabane, Lehana; Hutton, Eileen

    2014-09-26

    Clustering of outcomes at centers involved in multicenter trials is a type of center effect. The Consolidated Standards of Reporting Trials Statement recommends that multicenter randomized controlled trials (RCTs) should account for center effects in their analysis, however most do not. The Early External Cephalic Version (EECV) trials published in 2003 and 2011 stratified by center at randomization, but did not account for center in the analyses, and due to the nature of the intervention and number of centers, may have been prone to center effects. Using data from the EECV trials, we undertook an empirical study to compare various statistical approaches to account for center effect while estimating the impact of external cephalic version timing (early or delayed) on the outcomes of cesarean section, preterm birth, and non-cephalic presentation at the time of birth. The data from the EECV pilot trial and the EECV2 trial were merged into one dataset. Fisher's exact method was used to test the overall effect of external cephalic version timing unadjusted for center effects. Seven statistical models that accounted for center effects were applied to the data. The models included: i) the Mantel-Haenszel test, ii) logistic regression with fixed center effect and fixed treatment effect, iii) center-size weighted and iv) un-weighted logistic regression with fixed center effect and fixed treatment-by-center interaction, iv) logistic regression with random center effect and fixed treatment effect, v) logistic regression with random center effect and random treatment-by-center interaction, and vi) generalized estimating equations. For each of the three outcomes of interest approaches to account for center effect did not alter the overall findings of the trial. The results were similar for the majority of the methods used to adjust for center, illustrating the robustness of the findings. Despite literature that suggests center effect can change the estimate of effect in multicenter trials, this empirical study does not show a difference in the outcomes of the EECV trials when accounting for center effect. The EECV2 trial was registered on 30 July 30 2005 with Current Controlled Trials: ISRCTN 56498577.

  16. It's what's on the outside that matters: an advantage for external features in children's word recognition.

    PubMed

    Webb, Tessa M; Beech, John R; Mayall, Kate M; Andrews, Antony S

    2006-06-01

    The relative importance of internal and external letter features of words in children's developing reading was investigated to clarify further the nature of early featural analysis. In Experiment 1, 72 6-, 8-, and 10-year-olds read aloud words displayed as wholes, external features only (central features missing, thereby preserving word shape information), or internal features only (central features preserved). There was an improvement in the processing of external features compared with internal features as reading experience increased. Experiment 2 examined the processing of the internal and external features of words employing a forward priming paradigm with 60 8-, 10-, and 12-year-olds. Reaction times to internal feature primes were equivalent to a nonprime blank condition, whereas responses to external feature primes were faster than those to the other two prime types. This advantage for the external features of words is discussed in terms of an early and enduring role for processing the external visual features in words during reading development.

  17. Self-organisation of random oscillators with Lévy stable distributions

    NASA Astrophysics Data System (ADS)

    Moradi, Sara; Anderson, Johan

    2017-08-01

    A novel possibility of self-organized behaviour of stochastically driven oscillators is presented. It is shown that synchronization by Lévy stable processes is significantly more efficient than that by oscillators with Gaussian statistics. The impact of outlier events from the tail of the distribution function was examined by artificially introducing a few additional oscillators with very strong coupling strengths and it is found that remarkably even one such rare and extreme event may govern the long term behaviour of the coupled system. In addition to the multiplicative noise component, we have investigated the impact of an external additive Lévy distributed noise component on the synchronisation properties of the oscillators.

  18. Nonlinear Rheology in a Model Biological Tissue

    NASA Astrophysics Data System (ADS)

    Matoz-Fernandez, D. A.; Agoritsas, Elisabeth; Barrat, Jean-Louis; Bertin, Eric; Martens, Kirsten

    2017-04-01

    The rheological response of dense active matter is a topic of fundamental importance for many processes in nature such as the mechanics of biological tissues. One prominent way to probe mechanical properties of tissues is to study their response to externally applied forces. Using a particle-based model featuring random apoptosis and environment-dependent division rates, we evidence a crossover from linear flow to a shear-thinning regime with an increasing shear rate. To rationalize this nonlinear flow we derive a theoretical mean-field scenario that accounts for the interplay of mechanical and active noise in local stresses. These noises are, respectively, generated by the elastic response of the cell matrix to cell rearrangements and by the internal activity.

  19. Inter-organizational collaboration in the implementation of evidence-based practices among public agencies serving abused and neglected youth.

    PubMed

    Palinkas, Lawrence A; Fuentes, Dahlia; Finno, Megan; Garcia, Antonio R; Holloway, Ian W; Chamberlain, Patricia

    2014-01-01

    This study examined the role of inter-organizational collaboration in implementing new evidence-based practices for addressing problem behaviors in at-risk youth. Semi-structured interviews were conducted with 38 systems leaders of probation, mental health, and child welfare departments of 12 California counties participating in a large randomized controlled trial to scale-up the use of Multidimensional Treatment Foster Care. Three sets of collaboration characteristics were identified: (1) characteristics of collaboration process, (2) characteristics of the external environment, and (3) characteristics of participating organizations and individuals. Inter-organizational collaboration enables an exchange of information and advice and a pooling of resources individual agencies may require for successful implementation.

  20. Complete Nagy-Soper subtraction for next-to-leading order calculations in QCD

    NASA Astrophysics Data System (ADS)

    Bevilacqua, G.; Czakon, M.; Kubocz, M.; Worek, M.

    2013-10-01

    We extend the Helac-Dipoles package with the implementation of a new subtraction formalism, first introduced by Nagy and Soper in the formulation of an improved parton shower. We discuss a systematic, semi-numerical approach for the evaluation of the integrated subtraction terms for both massless and massive partons, which provides the missing ingredient for a complete implementation. In consequence, the new scheme can now be used as part of a complete NLO QCD calculation for processes with arbitrary parton masses and multiplicities. We assess its overall performance through a detailed comparison with results based on Catani-Seymour subtraction. The importance of random polarization and color sampling of the external partons is also examined.

  1. Evaluation of a women group led health communication program in Haryana, India.

    PubMed

    Kaur, Manmeet; Jaswal, Nidhi; Saddi, Anil Kumar

    2017-12-01

    Sakshar Mahila Smooh (SMS) program was launched in rural areas of Haryana in India during 2008. A total of 6788 SMSs, each having 5-10 literate women, were equipped to enhance health communication. We carried out process evaluation of this program as an external agency. After a review of program documents, a random sample survey of Auxiliary Nurse Midwives (ANMs), SMS members, and village women was conducted. Out of four divisions of the state, one was randomly chosen, which had five districts. From 330 randomly chosen villages, 283 ANMs, 1164 SMS members, and 1123 village women were interviewed using a semi- structured interview schedule. Program inputs, processes, and outputs were compared in the five districts. Chi square was used for significance test. In the sampled division, out of 2009 villages, 1732 (86%) had functional SMS. In three years, SMS conducted 15036 group meetings, 2795 rallies, 2048 wall writings, and 803 competitions, and 44.5% of allocated budget was utilized. Most ANMs opined that SMSs are better health communicators. SMS members were aware about their roles and responsibilities. Majority of village women reported that SMS carry out useful health education activities. The characteristics of SMS members were similar but program performance was better in districts where health managers were proactive in program planning and monitoring. SMS Program has communicated health messages to majority of rural population, however, better planning & monitoring can improve program performance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Best strategies to implement clinical pathways in an emergency department setting: study protocol for a cluster randomized controlled trial.

    PubMed

    Jabbour, Mona; Curran, Janet; Scott, Shannon D; Guttman, Astrid; Rotter, Thomas; Ducharme, Francine M; Lougheed, M Diane; McNaughton-Filion, M Louise; Newton, Amanda; Shafir, Mark; Paprica, Alison; Klassen, Terry; Taljaard, Monica; Grimshaw, Jeremy; Johnson, David W

    2013-05-22

    The clinical pathway is a tool that operationalizes best evidence recommendations and clinical practice guidelines in an accessible format for 'point of care' management by multidisciplinary health teams in hospital settings. While high-quality, expert-developed clinical pathways have many potential benefits, their impact has been limited by variable implementation strategies and suboptimal research designs. Best strategies for implementing pathways into hospital settings remain unknown. This study will seek to develop and comprehensively evaluate best strategies for effective local implementation of externally developed expert clinical pathways. We will develop a theory-based and knowledge user-informed intervention strategy to implement two pediatric clinical pathways: asthma and gastroenteritis. Using a balanced incomplete block design, we will randomize 16 community emergency departments to receive the intervention for one clinical pathway and serve as control for the alternate clinical pathway, thus conducting two cluster randomized controlled trials to evaluate this implementation intervention. A minimization procedure will be used to randomize sites. Intervention sites will receive a tailored strategy to support full clinical pathway implementation. We will evaluate implementation strategy effectiveness through measurement of relevant process and clinical outcomes. The primary process outcome will be the presence of an appropriately completed clinical pathway on the chart for relevant patients. Primary clinical outcomes for each clinical pathway include the following: Asthma--the proportion of asthmatic patients treated appropriately with corticosteroids in the emergency department and at discharge; and Gastroenteritis--the proportion of relevant patients appropriately treated with oral rehydration therapy. Data sources include chart audits, administrative databases, environmental scans, and qualitative interviews. We will also conduct an overall process evaluation to assess the implementation strategy and an economic analysis to evaluate implementation costs and benefits. This study will contribute to the body of evidence supporting effective strategies for clinical pathway implementation, and ultimately reducing the research to practice gaps by operationalizing best evidence care recommendations through effective use of clinical pathways. ClinicalTrials.gov: NCT01815710.

  3. Polarization of gamma-ray burst afterglows in the synchrotron self-Compton process from a highly relativistic jet

    NASA Astrophysics Data System (ADS)

    Lin, Hai-Nan; Li, Xin; Chang, Zhe

    2017-04-01

    Linear polarization has been observed in both the prompt phase and afterglow of some bright gamma-ray bursts (GRBs). Polarization in the prompt phase spans a wide range, and may be as high as ≳ 50%. In the afterglow phase, however, it is usually below 10%. According to the standard fireball model, GRBs are produced by synchrotron radiation and Compton scattering process in a highly relativistic jet ejected from the central engine. It is widely accepted that prompt emissions occur in the internal shock when shells with different velocities collide with each other, and the magnetic field advected by the jet from the central engine can be ordered on a large scale. On the other hand, afterglows are often assumed to occur in the external shock when the jet collides with interstellar medium, and the magnetic field produced by the shock through, for example, Weibel instability, is possibly random. In this paper, we calculate the polarization properties of the synchrotron self-Compton process from a highly relativistic jet, in which the magnetic field is randomly distributed in the shock plane. We also consider the generalized situation where a uniform magnetic component perpendicular to the shock plane is superposed on the random magnetic component. We show that it is difficult for the polarization to be larger than 10% if the seed electrons are isotropic in the jet frame. This may account for the observed upper limit of polarization in the afterglow phase of GRBs. In addition, if the random and uniform magnetic components decay with time at different speeds, then the polarization angle may change 90° during the temporal evolution. Supported by Fundamental Research Funds for the Central Universities (106112016CDJCR301206), National Natural Science Fund of China (11375203, 11603005), and Open Project Program of State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, China (Y5KF181CJ1)

  4. Parent-Child Relationship Quality and Family Transmission of Parent Posttraumatic Stress Disorder Symptoms and Child Externalizing and Internalizing Symptoms Following Fathers’ Combat-Trauma Exposure

    PubMed Central

    Snyder, James; Gewirtz, Abigail; Schrepferman, Lynn; Gird, Suzanne R.; Quattlebaum, Jamie; Pauldine, Michael R.; Elish, Katie; Zamir, Osnat; Hayes, Charles

    2016-01-01

    Transactional cascades among child internalizing and externalizing symptoms, and fathers’ and mothers’ post-traumatic stress disorder symptoms were examined in a sample of families with a male parent who had been deployed to recent military conflicts in the Middle East. The role of parents’ positive engagement and coercive interaction with their child, and family members’ emotion regulation were tested as processes linking cascades of parent and child symptoms. A subsample of 183 families with deployed fathers and non-deployed mothers and their 4 to 13 year old children who participated in a randomized control trial intervention (After Deployment: Adaptive Parenting Tools, or ADAPT) were assessed at baseline prior to intervention, and at 12 and 24 months after baseline, using parent reports of their own and their child’s symptoms. Parents’ observed behavior during interaction with their children was coded using a multi-method approach at each assessment point. Reciprocal cascades among fathers’ and mothers’ PTSD symptoms, and child internalizing and externalizing symptoms were observed. Fathers’ and mothers’ positive engagement during parent-child interaction linked their PTSD symptoms and their child’s internalizing symptoms. Fathers’ and mothers’ coercive behavior toward their child linked their PTSD symptoms and their child’s externalizing symptoms. Each family members’ capacity for emotion regulation was associated with their adjustment problems at baseline. Implications for intervention, and for research using longitudinal models and a family-systems perspective of co-occurrence and cascades of symptoms across family members are described. PMID:27739388

  5. Electric-Field-Directed Parallel Alignment Architecting 3D Lithium-Ion Pathways within Solid Composite Electrolyte.

    PubMed

    Liu, Xueqing; Peng, Sha; Gao, Shuyu; Cao, Yuancheng; You, Qingliang; Zhou, Liyong; Jin, Yongcheng; Liu, Zhihong; Liu, Jiyan

    2018-05-09

    It is of great significance to seek high-performance solid electrolytes via a facile chemistry and simple process for meeting the requirements of solid batteries. Previous reports revealed that ion conducting pathways within ceramic-polymer composite electrolytes mainly occur at ceramic particles and the ceramic-polymer interface. Herein, one facile strategy toward ceramic particles' alignment and assembly induced by an external alternating-current (AC) electric field is presented. It was manifested by an in situ optical microscope that Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 particles and poly(ethylene glycol) diacrylate in poly(dimethylsiloxane) (LATP@PEGDA@PDMS) assembled into three-dimensional connected networks on applying an external AC electric field. Scanning electron microscopy revealed that the ceramic LATP particles aligned into a necklacelike assembly. Electrochemical impedance spectroscopy confirmed that the ionic conductivity of this necklacelike alignment was significantly enhanced compared to that of the random one. It was demonstrated that this facile strategy of applying an AC electric field can be a very effective approach for architecting three-dimensional lithium-ion conductive networks within solid composite electrolyte.

  6. Experimental Errors in QSAR Modeling Sets: What We Can Do and What We Cannot Do.

    PubMed

    Zhao, Linlin; Wang, Wenyi; Sedykh, Alexander; Zhu, Hao

    2017-06-30

    Numerous chemical data sets have become available for quantitative structure-activity relationship (QSAR) modeling studies. However, the quality of different data sources may be different based on the nature of experimental protocols. Therefore, potential experimental errors in the modeling sets may lead to the development of poor QSAR models and further affect the predictions of new compounds. In this study, we explored the relationship between the ratio of questionable data in the modeling sets, which was obtained by simulating experimental errors, and the QSAR modeling performance. To this end, we used eight data sets (four continuous endpoints and four categorical endpoints) that have been extensively curated both in-house and by our collaborators to create over 1800 various QSAR models. Each data set was duplicated to create several new modeling sets with different ratios of simulated experimental errors (i.e., randomizing the activities of part of the compounds) in the modeling process. A fivefold cross-validation process was used to evaluate the modeling performance, which deteriorates when the ratio of experimental errors increases. All of the resulting models were also used to predict external sets of new compounds, which were excluded at the beginning of the modeling process. The modeling results showed that the compounds with relatively large prediction errors in cross-validation processes are likely to be those with simulated experimental errors. However, after removing a certain number of compounds with large prediction errors in the cross-validation process, the external predictions of new compounds did not show improvement. Our conclusion is that the QSAR predictions, especially consensus predictions, can identify compounds with potential experimental errors. But removing those compounds by the cross-validation procedure is not a reasonable means to improve model predictivity due to overfitting.

  7. Experimental Errors in QSAR Modeling Sets: What We Can Do and What We Cannot Do

    PubMed Central

    2017-01-01

    Numerous chemical data sets have become available for quantitative structure–activity relationship (QSAR) modeling studies. However, the quality of different data sources may be different based on the nature of experimental protocols. Therefore, potential experimental errors in the modeling sets may lead to the development of poor QSAR models and further affect the predictions of new compounds. In this study, we explored the relationship between the ratio of questionable data in the modeling sets, which was obtained by simulating experimental errors, and the QSAR modeling performance. To this end, we used eight data sets (four continuous endpoints and four categorical endpoints) that have been extensively curated both in-house and by our collaborators to create over 1800 various QSAR models. Each data set was duplicated to create several new modeling sets with different ratios of simulated experimental errors (i.e., randomizing the activities of part of the compounds) in the modeling process. A fivefold cross-validation process was used to evaluate the modeling performance, which deteriorates when the ratio of experimental errors increases. All of the resulting models were also used to predict external sets of new compounds, which were excluded at the beginning of the modeling process. The modeling results showed that the compounds with relatively large prediction errors in cross-validation processes are likely to be those with simulated experimental errors. However, after removing a certain number of compounds with large prediction errors in the cross-validation process, the external predictions of new compounds did not show improvement. Our conclusion is that the QSAR predictions, especially consensus predictions, can identify compounds with potential experimental errors. But removing those compounds by the cross-validation procedure is not a reasonable means to improve model predictivity due to overfitting. PMID:28691113

  8. A Prospective Randomized Controlled Trial of the Efficacy of External Physical Vibration Lithecbole after Extracorporeal Shock Wave Lithotripsy for a Lower Pole Renal Stone Less Than 2 cm.

    PubMed

    Long, Qilai; Zhang, Jian; Xu, Zhibing; Zhu, Yanjun; Liu, Li; Wang, Hang; Guo, Jianming; Wang, Guomin

    2016-04-01

    We evaluate the efficacy and safety of external physical vibration lithecbole in improving the clearance rates of lower pole renal stones after shock wave lithotripsy. A total of 71 patients with lower pole renal stones (6 to 20 mm) were prospectively randomized into 2 groups. In the treatment group 34 patients were treated with external physical vibration lithecbole after shock wave lithotripsy. In the control group 37 patients underwent shock wave lithotripsy only. External physical vibration lithecbole was performed without anesthesia by the same team using the Friend-I External Physical Vibration Lithecbole (Fu Jian Da Medical Instrument Co., Ltd, Zhengzhou, China). The stone-free rate, stone expulsion rate, stone expulsion time and incidence of complications were monitored. External physical vibration lithecbole was successful in assisting the discharge of stone fragments. The stone-free status was 76.5% in the treatment group and 48.6% in the control group (p=0.008). Stone expulsion rates at day 1, week 1 and week 3 were 76.5% (26), 94.1% (32) and 94.1% (32) in the treatment group vs 43.2% (16), 73.0% (27) and 89.2% (33) in the control group, respectively. Mean stone fragment expulsion time was 11.2 minutes in the treatment group and 9.17 hours in the control group (p=0.016). There was no significant difference in complications between the 2 groups (p >0.05). External physical vibration lithecbole was efficacious in assisting the discharge of lower pole renal stone fragments and can be used as an adjunctive method of minimally invasive stone treatment. However, additional investigations are needed to confirm the efficacy. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  9. Deepening our understanding of quality improvement in Europe (DUQuE): overview of a study of hospital quality management in seven countries.

    PubMed

    Secanell, Mariona; Groene, Oliver; Arah, Onyebuchi A; Lopez, Maria Andrée; Kutryba, Basia; Pfaff, Holger; Klazinga, Niek; Wagner, Cordula; Kristensen, Solvejg; Bartels, Paul Daniel; Garel, Pascal; Bruneau, Charles; Escoval, Ana; França, Margarida; Mora, Nuria; Suñol, Rosa

    2014-04-01

    This paper provides an overview of the DUQuE (Deepening our Understanding of Quality Improvement in Europe) project, the first study across multiple countries of the European Union (EU) to assess relationships between quality management and patient outcomes at EU level. The paper describes the conceptual framework and methods applied, highlighting the novel features of this study. DUQuE was designed as a multi-level cross-sectional study with data collection at hospital, pathway, professional and patient level in eight countries. We aimed to collect data for the assessment of hospital-wide constructs from up to 30 randomly selected hospitals in each country, and additional data at pathway and patient level in 12 of these 30. A comprehensive conceptual framework was developed to account for the multiple levels that influence hospital performance and patient outcomes. We assessed hospital-specific constructs (organizational culture and professional involvement), clinical pathway constructs (the organization of care processes for acute myocardial infarction, stroke, hip fracture and deliveries), patient-specific processes and outcomes (clinical effectiveness, patient safety and patient experience) and external constructs that could modify hospital quality (external assessment and perceived external pressure). Data was gathered from 188 hospitals in 7 participating countries. The overall participation and response rate were between 75% and 100% for the assessed measures. This is the first study assessing relation between quality management and patient outcomes at EU level. The study involved a large number of respondents and achieved high response rates. This work will serve to develop guidance in how to assess quality management and makes recommendations on the best ways to improve quality in healthcare for hospital stakeholders, payers, researchers, and policy makers throughout the EU.

  10. A cluster-randomized controlled knowledge translation feasibility study in Alberta community pharmacies using the PARiHS framework: study protocol.

    PubMed

    Rosenthal, Meagen M; Tsuyuki, Ross T; Houle, Sherilyn Kd

    2015-01-01

    Despite evidence of benefit for pharmacist involvement in chronic disease management, the provision of these services in community pharmacy has been suboptimal. The Promoting Action on Research Implementation in Health Services (PARiHS) framework suggests that for knowledge translation to be effective, there must be evidence of benefit, a context conducive to implementation, and facilitation to support uptake. We hypothesize that while the evidence and context components of this framework are satisfied, that uptake into practice has been insufficient because of a lack of facilitation. This protocol describes the rationale and methods of a feasibility study to test a facilitated pharmacy practice intervention based on the PARiHS framework, to assist community pharmacists in increasing the number of formal and documented medication management services completed for patients with diabetes, dyslipidemia, and hypertension. A cluster-randomized before-after design will compare ten pharmacies from within a single organization, with the unit of randomization being the pharmacy. Pharmacies will be randomized to facilitated intervention based on the PARiHS framework or usual practice. The Alberta Context Tool will be used to establish the context of practice in each pharmacy. Pharmacies randomized to the intervention will receive task-focused facilitation from an external facilitator, with the goal of developing alternative team processes to allow the greater provision of medication management services for patients with diabetes, hypertension, and dyslipidemia. The primary outcome will be a process evaluation of the needs of community pharmacies to provide more clinical services, the acceptability and uptake of modifications made, and the willingness of pharmacies to participate. Secondary outcomes will include the change in the number of formal and documented medication management services in the aforementioned chronic conditions provided 6 months before, versus after, the intervention between the two groups, and identification of feasible quantitative outcomes for evaluating the effect of the intervention on patient care outcomes. To date, the study has identified and enrolled the ten pharmacies required and initiated the intervention process. This study will be the first to examine the role of facilitation in pharmacy practice, with the goal of scalable and sustainable practice change. Clinicaltrials.gov identifier NCT02191111.

  11. Amplitude and phase fluctuations of Van der Pol oscillator under external random forcing

    NASA Astrophysics Data System (ADS)

    Singh, Aman K.; Yadava, R. D. S.

    2018-05-01

    The paper presents an analytical study of noise in Van der Pol oscillator output subjected to an external force noise assumed to be characterized by delta function (white noise). The external fluctuations are assumed to be small in comparison to the average response of the noise free system. The autocorrelation function and power spectrum are calculated under the condition of weak nonlinearity. The latter ensures limit cycle oscillations. The total spectral power density is dominated by the contributions from the phase fluctuations. The amplitude fluctuations are at least two orders of magnitude smaller. The analysis is shown to be useful to interpretation microcantilever based biosensing data.

  12. Forced magnetohydrodynamic turbulence in a uniform external magnetic field

    NASA Technical Reports Server (NTRS)

    Hossain, M.; Vahala, G.; Montgomery, D.

    1985-01-01

    Two-dimensional dissipative MHD turbulence is randomly driven at small spatial scales and is studied by numerical simulation in the presence of a strong uniform external magnetic field. A behavior is observed which is apparently distinct from the inverse cascade which prevails in the absence of an external magnetic field. The magnetic spectrum becomes dominated by the three longest wavelength Alfven waves in the system allowed by the boundary conditions: those which, in a box size of edge 2 pi, have wave numbers (kx, ky) = (1, 1), and (1, -1), where the external magnetic field is in the x direction. At any given instant, one of these three modes dominates the vector potential spectrum, but they do not constitute a resonantly coupled triad. Rather, they are apparently coupled by the smaller-scale turbulence.

  13. Forced MHD turbulence in a uniform external magnetic field

    NASA Technical Reports Server (NTRS)

    Hossain, M.; Vahala, G.; Montgomery, D.

    1985-01-01

    Two-dimensional dissipative MHD turbulence is randomly driven at small spatial scales and is studied by numerical simulation in the presence of a strong uniform external magnetic field. A behavior is observed which is apparently distinct from the inverse cascade which prevails in the absence of an external magnetic field. The magnetic spectrum becomes dominated by the three longest wavelength Alfven waves in the system allowed by the boundary conditions: those which, in a box size of edge 2 pi, have wave numbers (kx' ky) = (1, 1), and (1, -1), where the external magnetic field is in the x direction. At any given instant, one of these three modes dominates the vector potential spectrum, but they do not constitute a resonantly coupled triad. Rather, they are apparently coupled by the smaller-scale turbulence.

  14. [Observation on therapeutic effect of acupuncture at Yanglingquan (GB 34) on sprain of external ankle joint].

    PubMed

    He, Xin-fang; Xu, Hai-bin

    2006-08-01

    To observe the increasing effect of Yanglingquan (GB 34) on sprain of external ankle joint. Seventy-nine cases of sprain of external ankle joint were semi-randomly divided into a treatment group (n = 46) and a control group (n = 33). The treatment group were treated with acupuncture at Yanglingquan (GB 34) and electro-magnetic therapy at local acupoints, and the control group with electro-magnetic therapy. The cured rate and the total effective rate were 67.4% and 91.3% in the treatment group, and 36.4% and 69.7% in the control group, respectively, with a significant difference between the two groups (P<0.01, P<0.05). Acupuncture at Yanglingquan (GB 34) has a better therapeutic effect on sprain of the external ankle joint.

  15. The effect of childhood malnutrition on externalizing behavior.

    PubMed

    Liu, Jianghong; Raine, Adrian

    2006-10-01

    Childhood externalizing behavior (aggression, hyperactivity, and conduct disorder) has been increasingly viewed as a public health problem because of its etiology and outcome. The association between malnutrition and externalizing behavior has begun to receive attention. This review summarizes recent empirical findings on malnutrition as a risk factor for the development of externalizing behavior, with an emphasis on micronutrient deficiency, and explores brain dysfunction as a possible mechanism. Externalizing behavior is associated with both macromalnutrition (e.g. protein) and micromalnutrition (e.g. iron and zinc). Both prenatal and postnatal malnutrition is implicated. The long-term effects of malnutrition on behavior could be reversible. The effects of docosahexaenoic acid/omega-3 long-chain essential fatty acid on externalizing behavior are more mixed. From animal and human findings, it is hypothesized that malnutrition impairs neurocognitive functioning by reducing neurons, alternating neurotransmitter functioning, and increasing neurotoxicity, and that such neurocognitive impairments predispose to externalizing behavior. Different lines of evidence support the view that poor nutrition contributes to the development of child behavior problems. More randomized, controlled trials that manipulate nutritional intake and evaluate behavior in children are needed to evaluate the etiological role of nutrition in externalizing behavior in order to inform intervention and prevention efforts.

  16. Comparing Resident Self-Report to Chart Audits for Quality Improvement Projects: Accurate Reflection or Cherry-Picking?

    PubMed Central

    Kuperman, Ethan F.; Tobin, Kristen; Kraschnewski, Jennifer L.

    2014-01-01

    Background Resident engagement in quality improvement is a requirement for graduate medical education, but the optimal means of instruction and evaluation of resident progress remain unknown. Objective To determine the accuracy of self-reported chart audits in measuring resident adherence to primary care clinical practice guidelines. Methods During the 2010–2011 academic year, second- and third-year internal medicine residents at a single, university hospital–based program performed chart audits on 10 patients from their primary care clinic to determine adherence to 16 US Preventive Services Task Force primary care guidelines. We compared residents' responses to independent audits of randomly selected patient charts by a single external reviewer. Results Self-reported data were collected by 18 second-year and 15 third-year residents for 330 patients. Independently, 70 patient charts were randomly selected for review by an external auditor. Overall guideline compliance was significantly higher on self-reported audits compared to external audits (82% versus 68%, P < .001). Of 16 guidelines, external audits found significantly lower rates of adherence for 5 (tetanus vaccination, osteoporosis screening, colon cancer screening, cholesterol screening, and obesity screening). Chlamydia screening was more common in audited charts than in self-reported data. Although third-year residents self-reported higher guideline adherence than second-year residents (86% versus 78%, P < .001), external audits for third-year residents found lower overall adherence (64% versus 72%, P  =  .040). Conclusions Residents' self-reported chart audits may significantly overestimate guideline adherence. Increased supervision and independent review appear necessary to accurately evaluate resident performance. PMID:26140117

  17. Effectiveness of external cold and vibration for procedural pain relief during peripheral intravenous cannulation in pediatric patients.

    PubMed

    Canbulat, Nejla; Ayhan, Fatma; Inal, Sevil

    2015-02-01

    The aim of this study was to investigate the effect of external cold and vibration stimulation via Buzzy on the pain and anxiety level of children during peripheral intravenous (IV) cannulation. This study was a prospective, randomized controlled trial. The sample consisted of 176 children ages 7 to 12 years who were randomly assigned to two groups: a control group that received no peripheral IV cannulation intervention and an experimental group that received external cold and vibration via Buzzy. The same nurse conducted the peripheral IV cannulation in all the children, and the same researcher applied the external cold and vibration to all the children. The external cold and the vibration were applied 1 minute before the peripheral IV cannulation procedure and continued until the end of the procedure. Preprocedural anxiety was assessed using the Children's Fear Scale, along with reports by the children, their parents, and an observer. Procedural anxiety was assessed with the Children's Fear Scale and the parents' and the observer's reports. Procedural pain was assessed using the Wong Baker Faces Scale and the visual analog scale self-reports of the children. Preprocedural anxiety did not differ significantly. Comparison of the two groups showed significantly lower pain and anxiety levels in the experimental group than in the control group during the peripheral IV cannulation. Buzzy can be considered to provide an effective combination of coldness and vibration. This method can be used during pediatric peripheral IV cannulation by pediatric nurses. Copyright © 2015 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

  18. Comparing Resident Self-Report to Chart Audits for Quality Improvement Projects: Accurate Reflection or Cherry-Picking?

    PubMed

    Kuperman, Ethan F; Tobin, Kristen; Kraschnewski, Jennifer L

    2014-12-01

    Resident engagement in quality improvement is a requirement for graduate medical education, but the optimal means of instruction and evaluation of resident progress remain unknown. To determine the accuracy of self-reported chart audits in measuring resident adherence to primary care clinical practice guidelines. During the 2010-2011 academic year, second- and third-year internal medicine residents at a single, university hospital-based program performed chart audits on 10 patients from their primary care clinic to determine adherence to 16 US Preventive Services Task Force primary care guidelines. We compared residents' responses to independent audits of randomly selected patient charts by a single external reviewer. Self-reported data were collected by 18 second-year and 15 third-year residents for 330 patients. Independently, 70 patient charts were randomly selected for review by an external auditor. Overall guideline compliance was significantly higher on self-reported audits compared to external audits (82% versus 68%, P < .001). Of 16 guidelines, external audits found significantly lower rates of adherence for 5 (tetanus vaccination, osteoporosis screening, colon cancer screening, cholesterol screening, and obesity screening). Chlamydia screening was more common in audited charts than in self-reported data. Although third-year residents self-reported higher guideline adherence than second-year residents (86% versus 78%, P < .001), external audits for third-year residents found lower overall adherence (64% versus 72%, P  =  .040). Residents' self-reported chart audits may significantly overestimate guideline adherence. Increased supervision and independent review appear necessary to accurately evaluate resident performance.

  19. Mean first passage time of active Brownian particle in one dimension

    NASA Astrophysics Data System (ADS)

    Scacchi, A.; Sharma, A.

    2018-02-01

    We investigate the mean first passage time of an active Brownian particle in one dimension using numerical simulations. The activity in one dimension is modelled as a two state model; the particle moves with a constant propulsion strength but its orientation switches from one state to other as in a random telegraphic process. We study the influence of a finite resetting rate r on the mean first passage time to a fixed target of a single free active Brownian particle and map this result using an effective diffusion process. As in the case of a passive Brownian particle, we can find an optimal resetting rate r* for an active Brownian particle for which the target is found with the minimum average time. In the case of the presence of an external potential, we find good agreement between the theory and numerical simulations using an effective potential approach.

  20. Inverse four-wave-mixing and self-parametric amplification effect in optical fibre

    PubMed Central

    Turitsyn, Sergei K.; Bednyakova, Anastasia E.; Fedoruk, Mikhail P.; Papernyi, Serguei B.; Clements, Wallace R.L.

    2015-01-01

    An important group of nonlinear processes in optical fibre involves the mixing of four waves due to the intensity dependence of the refractive index. It is customary to distinguish between nonlinear effects that require external/pumping waves (cross-phase modulation and parametric processes such as four-wave mixing) and self-action of the propagating optical field (self-phase modulation and modulation instability). Here, we present a new nonlinear self-action effect, self-parametric amplification (SPA), which manifests itself as optical spectrum narrowing in normal dispersion fibre, leading to very stable propagation with a distinctive spectral distribution. The narrowing results from an inverse four-wave mixing, resembling an effective parametric amplification of the central part of the spectrum by energy transfer from the spectral tails. SPA and the observed stable nonlinear spectral propagation with random temporal waveform can find applications in optical communications and high power fibre lasers with nonlinear intra-cavity dynamics. PMID:26345290

  1. Why did I get cancer? Perceptions of childhood cancer survivors in Korea.

    PubMed

    Yi, Jaehee; Kim, Min Ah; Parsons, Bridget G; Wu, Yelena P

    2018-04-01

    This study explored whether and how childhood cancer survivors in Korea ask and resolve the question of what may have caused their cancer. Thirty-one childhood cancer survivors participated in in-depth interviews about their self-questioning process in this regard. The findings indicate that Korean childhood cancer survivors pondered this question alone due to the stigma attached to cancer in the family and society. Their answers included internal factors (doing "bad things," having unhealthy eating habits, engaging in magical thinking, having a stress-prone personality, or having a biological susceptibility) or external factors (stressors, random events, the environment, or medical conditions). How they perceived the cause of cancer had an impact on aspects of their current lives. Psychosocial care standards or guidelines are needed in regard to the provision of a safe environment in which Korean cancer survivors and their parents can share their perceptions and process their thoughts.

  2. Quality and Safety in Health Care, Part XIV: The External Environment and Research for Diagnostic Processes.

    PubMed

    Harolds, Jay A

    2016-09-01

    The work system in which diagnosis takes place is affected by the external environment, which includes requirements such as certification, accreditation, and regulations. How errors are reported, malpractice, and the system for payment are some other aspects of the external environment. Improving the external environment is expected to decrease errors in diagnosis. More research on improving the diagnostic process is needed.

  3. Optimal marker placement in hadrontherapy: intelligent optimization strategies with augmented Lagrangian pattern search.

    PubMed

    Altomare, Cristina; Guglielmann, Raffaella; Riboldi, Marco; Bellazzi, Riccardo; Baroni, Guido

    2015-02-01

    In high precision photon radiotherapy and in hadrontherapy, it is crucial to minimize the occurrence of geometrical deviations with respect to the treatment plan in each treatment session. To this end, point-based infrared (IR) optical tracking for patient set-up quality assessment is performed. Such tracking depends on external fiducial points placement. The main purpose of our work is to propose a new algorithm based on simulated annealing and augmented Lagrangian pattern search (SAPS), which is able to take into account prior knowledge, such as spatial constraints, during the optimization process. The SAPS algorithm was tested on data related to head and neck and pelvic cancer patients, and that were fitted with external surface markers for IR optical tracking applied for patient set-up preliminary correction. The integrated algorithm was tested considering optimality measures obtained with Computed Tomography (CT) images (i.e. the ratio between the so-called target registration error and fiducial registration error, TRE/FRE) and assessing the marker spatial distribution. Comparison has been performed with randomly selected marker configuration and with the GETS algorithm (Genetic Evolutionary Taboo Search), also taking into account the presence of organs at risk. The results obtained with SAPS highlight improvements with respect to the other approaches: (i) TRE/FRE ratio decreases; (ii) marker distribution satisfies both marker visibility and spatial constraints. We have also investigated how the TRE/FRE ratio is influenced by the number of markers, obtaining significant TRE/FRE reduction with respect to the random configurations, when a high number of markers is used. The SAPS algorithm is a valuable strategy for fiducial configuration optimization in IR optical tracking applied for patient set-up error detection and correction in radiation therapy, showing that taking into account prior knowledge is valuable in this optimization process. Further work will be focused on the computational optimization of the SAPS algorithm toward fast point-of-care applications. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Elective minimally invasive coronary artery bypass: Shunt or tournique occlusion? Assessment of a protective role of perioperative left anterior descending shunting on myocardial damage. A prospective randomized study

    PubMed Central

    2012-01-01

    Background To determine impact of intraluminal-left anterior descending shunt to prevent myocardial damage in minimally invasive coronary artery bypass. Methods 38 patients were randomly assigned to external tournique occlusion (n = 19) or intraluminal-left anterior descending shunt group (n = 19). Blood samples for cardiac troponin T were collected at 30 minutes prior to, 6 and 24 hours after surgery. Results One patient in external tournique occlusion and two patients in intraluminal-left anterior descending shunt group were excluded from futher analysis due to preoperative cardiac troponin T level above the 99th-percentile. Postoperatively, each six patients in external tournique occlusion (33.3%) and intraluminal-left anterior descending shunt (35.3%) group were above the 99th-percentile. Two patients from each group (external tournique occlusion group 11.1% vs. intraluminal-left anterior descending shunt group 11.8%) had peak values above 10-% coeficient of variation cutoff (p = 1). There were no significant differences in between both groups at all studied timepoints. Conclusion There was no protective effect of intraluminal shunting on myocardial damage compared to short-term tournique occlusion. It is upon the surgeon's discretion which method may preferrably be used to achieve a bloodless field in grafting of the non-occluded left anterior descending in minimally invasive coronary artery bypass. PMID:22809563

  5. Study of Nonlinear Dynamics of Intense Charged Particle Beams in the Paul Trap Simulator Experiment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Hua

    The Paul Trap Simulator Experiment (PTSX) is a compact laboratory device that simulates the nonlinear dynamics of intense charged particle beams propagating over a large distance in an alternating-gradient magnetic transport system. The radial quadrupole electric eld forces on the charged particles in the Paul Trap are analogous to the radial forces on the charged particles in the quadrupole magnetic transport system. The amplitude of oscillating voltage applied to the cylindrical electrodes in PTSX is equivalent to the quadrupole magnetic eld gradient in accelerators. The temporal periodicity in PTSX corresponds to the spatial periodicity in magnetic transport system. This thesismore » focuses on investigations of envelope instabilities and collective mode excitations, properties of high-intensity beams with significant space-charge effects, random noise-induced beam degradation and a laser-induced-fluorescence diagnostic. To better understand the nonlinear dynamics of the charged particle beams, it is critical to understand the collective processes of the charged particles. Charged particle beams support a variety of collective modes, among which the quadrupole mode and the dipole mode are of the greatest interest. We used quadrupole and dipole perturbations to excite the quadrupole and dipole mode respectively and study the effects of those collective modes on the charge bunch. The experimental and particle-in-cell (PIC) simulation results both show that when the frequency and the spatial structure of the external perturbation are matched with the corresponding collective mode, that mode will be excited to a large amplitude and resonates strongly with the external perturbation, usually causing expansion of the charge bunch and loss of particles. Machine imperfections are inevitable for accelerator systems, and we use random noise to simulate the effects of machine imperfection on the charged particle beams. The random noise can be Fourier decomposed into various frequency components and experimental results show that when the random noise has a large frequency component that matches a certain collective mode, the mode will also be excited and cause heating of the charge bunch. It is also noted that by rearranging the order of the random noise, the adverse effects of the random noise may be eliminated. As a non-destructive diagnostic method, a laser-induced- fluorescence (LIF) diagnostic is developed to study the transverse dynamics of the charged particle beams. The accompanying barium ion source and dye laser system are developed and tested.« less

  6. Realistic noise-tolerant randomness amplification using finite number of devices.

    PubMed

    Brandão, Fernando G S L; Ramanathan, Ravishankar; Grudka, Andrzej; Horodecki, Karol; Horodecki, Michał; Horodecki, Paweł; Szarek, Tomasz; Wojewódka, Hanna

    2016-04-21

    Randomness is a fundamental concept, with implications from security of modern data systems, to fundamental laws of nature and even the philosophy of science. Randomness is called certified if it describes events that cannot be pre-determined by an external adversary. It is known that weak certified randomness can be amplified to nearly ideal randomness using quantum-mechanical systems. However, so far, it was unclear whether randomness amplification is a realistic task, as the existing proposals either do not tolerate noise or require an unbounded number of different devices. Here we provide an error-tolerant protocol using a finite number of devices for amplifying arbitrary weak randomness into nearly perfect random bits, which are secure against a no-signalling adversary. The correctness of the protocol is assessed by violating a Bell inequality, with the degree of violation determining the noise tolerance threshold. An experimental realization of the protocol is within reach of current technology.

  7. Realistic noise-tolerant randomness amplification using finite number of devices

    NASA Astrophysics Data System (ADS)

    Brandão, Fernando G. S. L.; Ramanathan, Ravishankar; Grudka, Andrzej; Horodecki, Karol; Horodecki, Michał; Horodecki, Paweł; Szarek, Tomasz; Wojewódka, Hanna

    2016-04-01

    Randomness is a fundamental concept, with implications from security of modern data systems, to fundamental laws of nature and even the philosophy of science. Randomness is called certified if it describes events that cannot be pre-determined by an external adversary. It is known that weak certified randomness can be amplified to nearly ideal randomness using quantum-mechanical systems. However, so far, it was unclear whether randomness amplification is a realistic task, as the existing proposals either do not tolerate noise or require an unbounded number of different devices. Here we provide an error-tolerant protocol using a finite number of devices for amplifying arbitrary weak randomness into nearly perfect random bits, which are secure against a no-signalling adversary. The correctness of the protocol is assessed by violating a Bell inequality, with the degree of violation determining the noise tolerance threshold. An experimental realization of the protocol is within reach of current technology.

  8. Realistic noise-tolerant randomness amplification using finite number of devices

    PubMed Central

    Brandão, Fernando G. S. L.; Ramanathan, Ravishankar; Grudka, Andrzej; Horodecki, Karol; Horodecki, Michał; Horodecki, Paweł; Szarek, Tomasz; Wojewódka, Hanna

    2016-01-01

    Randomness is a fundamental concept, with implications from security of modern data systems, to fundamental laws of nature and even the philosophy of science. Randomness is called certified if it describes events that cannot be pre-determined by an external adversary. It is known that weak certified randomness can be amplified to nearly ideal randomness using quantum-mechanical systems. However, so far, it was unclear whether randomness amplification is a realistic task, as the existing proposals either do not tolerate noise or require an unbounded number of different devices. Here we provide an error-tolerant protocol using a finite number of devices for amplifying arbitrary weak randomness into nearly perfect random bits, which are secure against a no-signalling adversary. The correctness of the protocol is assessed by violating a Bell inequality, with the degree of violation determining the noise tolerance threshold. An experimental realization of the protocol is within reach of current technology. PMID:27098302

  9. Is ambulatory monitoring for "community-acquired" syncope economically attractive? A cost-effectiveness analysis of a randomized trial of external loop recorders versus Holter monitoring.

    PubMed

    Rockx, Marie Antoinette; Hoch, Jeffrey S; Klein, George J; Yee, Raymond; Skanes, Allan C; Gula, Lorne J; Krahn, Andrew D

    2005-11-01

    Out patient ambulatory monitoring is often performed in patients with syncope that present in the primary care setting to include or exclude an arrhythmia. The cost-effectiveness of 2 monitoring strategies was assessed in a prospective randomized trial. One hundred patients referred for ambulatory monitoring with syncope or presyncope were randomized to a 1-month external loop recorder (n = 49) or 48-hour Holter monitor (n = 51). Patients were offered crossover if there was failed activation or no symptom recurrence. The primary end point was symptom-rhythm correlation during monitoring. Direct costs were calculated based on the 2003 Ontario Health Insurance Plan fee schedule, combined with calculation of labor, materials, service, and overhead for diagnostic testing and related equipment. Before enrollment, the cost of all previous health care resource use was USD 472 +/- USD 397 (range USD 21-USD 1965). In the loop recorder group, 63% of patients had symptom recurrence and successful activation, compared with 24% in the Holter group (P < .0001). The cost per Holter was USD 177.64, and per loop recorder, USD 533.56, with a similar cost per diagnosis with the 2 techniques. The incremental cost-effectiveness ratio of the loop recorder was USD 901.74 per extra successful diagnosis. A strategy of Holter followed by offered loop recorder trended toward lower cost than initial loop recorder followed by Holter (USD 481 +/- USD 267 vs USD 551 +/- USD 83, P = .08), but was associated with a lower overall diagnostic yield (49% vs 63%) and a resultant higher cost per diagnosis (USD 982 vs USD 871, P = .08). Bootstrapping suggested that 90% of incremental cost-effectiveness ratios were less than USD 1250. Despite the increased upfront cost of external loop recorders, the marked improvement in diagnostic yield offsets the cost. External loop recorders are an economically attractive alternative. First-line use of external loop recorders in patients with "community-acquired" syncope and presyncope should be considered to optimize diagnostic yield given its value.

  10. Family Group Cognitive-Behavioral Preventive Intervention for Families of Depressed Parents: 18- and 24-month Outcomes

    PubMed Central

    Compas, Bruce E.; Forehand, Rex; Thigpen, Jennifer C.; Keller, Gary; Hardcastle, Emily J.; Cole, David A.; Potts, Jennifer; Haker, Kelly; Rakow, Aaron; Colletti, Christina; Reeslund, Kristen; Fear, Jessica; Garai, Emily; McKee, Laura; Merchant, M.J.; Roberts, Lorinda

    2014-01-01

    Objective In a long-term follow-up of a randomized controlled trial (Compas et al., 2009), to examine the effects at 18- and 24-month follow-ups of a Family Group Cognitive Behavioral (FGCB) preventive intervention for mental health outcomes for children and parents from families (N = 111) of parents with a history of major depressive disorder (MDD). Method Parents with a history of MDD and their 9 to 15-year-old children were randomly assigned to a FGCB intervention or a Written Information (WI) comparison condition. Children’s internalizing, externalizing, anxiety/depression, and depressive symptoms, episodes of MDD and other psychiatric diagnoses, and parents’ depressive symptoms and episodes of MDD were assessed at 18- and 24-months after randomization. Results Children in the FGCB condition were significantly lower in self-reports of anxiety/depression and internalizing symptoms at 18-months and significantly lower in externalizing symptoms at 18- and 24-months. Rates of MDD were significantly lower for children in the FGCB intervention over the 24-month follow-up (odds ratio = 2.91). No significant effects were found for parents’ symptoms of depression or episodes of MDD. Conclusions Support was found for a FGCB preventive intervention for children of parents with a history of MDD significantly reducing children’s episodes of MDD over a period of 2 years. Significant effects for the FGCB intervention were also found on internalizing and externalizing symptoms, with stronger effects at 18- than at 24-month follow-up. PMID:21707137

  11. Family group cognitive-behavioral preventive intervention for families of depressed parents: 18- and 24-month outcomes.

    PubMed

    Compas, Bruce E; Forehand, Rex; Thigpen, Jennifer C; Keller, Gary; Hardcastle, Emily J; Cole, David A; Potts, Jennifer; Watson, Kelly H; Rakow, Aaron; Colletti, Christina; Reeslund, Kristen; Fear, Jessica; Garai, Emily; McKee, Laura; Merchant, M J; Roberts, Lorinda

    2011-08-01

    In a long-term follow-up of a randomized controlled trial (Compas et al., 2009) to examine the effects at 18- and 24-month follow-ups of a family group cognitive-behavioral (FGCB) preventive intervention for mental health outcomes for children and parents from families (N = 111) of parents with a history of major depressive disorder (MDD). Parents with a history of MDD and their 9- to 15-year-old children were randomly assigned to a FGCB intervention or a written information comparison condition. Children's internalizing, externalizing, anxiety/depression, and depressive symptoms; episodes of MDD and other psychiatric diagnoses; and parents' depressive symptoms and episodes of MDD were assessed at 18 and 24 months after randomization. Children in the FGCB condition were significantly lower in self-reports of anxiety/depression and internalizing symptoms at 18 months and were significantly lower in self-reports of externalizing symptoms at 18 and 24 months. Rates of MDD were significantly lower for children in the FGCB intervention over the 24-month follow-up (odds ratio = 2.91). Marginal effects were found for parents' symptoms of depression at 18 and 24 months but not for episodes of MDD. Support was found for a FGCB preventive intervention for children of parents with a history of MDD significantly reducing children's episodes of MDD over a period of 2 years. Significant effects for the FGCB intervention were also found on internalizing and externalizing symptoms, with stronger effects at 18- than at 24-month follow-up.

  12. Rehabilitation of Executive Functions in Patients with Chronic Acquired Brain Injury with Goal Management Training, External Cuing, and Emotional Regulation: A Randomized Controlled Trial.

    PubMed

    Tornås, Sveinung; Løvstad, Marianne; Solbakk, Anne-Kristin; Evans, Jonathan; Endestad, Tor; Hol, Per Kristian; Schanke, Anne-Kristine; Stubberud, Jan

    2016-04-01

    Executive dysfunction is a common consequence of acquired brain injury (ABI), causing significant disability in daily life. This randomized controlled trial investigated the efficacy of Goal Management Training (GMT) in improving executive functioning in patients with chronic ABI. Seventy patients with a verified ABI and executive dysfunction were randomly allocated to GMT (n=33) or a psycho-educative active control condition, Brain Health Workshop (BHW) (n=37). In addition, all participants received external cueing by text messages. Neuropsychological tests and self-reported questionnaires of executive functioning were administered pre-intervention, immediately after intervention, and at 6 months follow-up. Assessors were blinded to group allocation. Questionnaire measures indicated significant improvement of everyday executive functioning in the GMT group, with effects lasting at least 6 months post-treatment. Both groups improved on the majority of the applied neuropsychological tests. However, improved performance on tests demanding executive attention was most prominent in the GMT group. The results indicate that GMT combined with external cueing is an effective metacognitive strategy training method, ameliorating executive dysfunction in daily life for patients with chronic ABI. The strongest effects were seen on self-report measures of executive functions 6 months post-treatment, suggesting that strategies learned in GMT were applied and consolidated in everyday life after the end of training. Furthermore, these findings show that executive dysfunction can be improved years after the ABI.

  13. The response of rotating machinery to external random vibration

    NASA Technical Reports Server (NTRS)

    Tessarzik, J. M.; Chiang, T.; Badgley, R. H.

    1974-01-01

    A high-speed turbogenerator employing gas-lubricated hydrodynamic journal and thrust bearings was subjected to external random vibrations for the purpose of assessing bearing performance in a dynamic environment. The pivoted-pad type journal bearings and the step-sector thrust bearing supported a turbine-driven rotor weighing approximately twenty-one pounds at a nominal operating speed of 36,000 rpm. The response amplitudes of both the rigid-supported and flexible-supported bearing pads, the gimballed thrust bearing, and the rotor relative to the machine casing were measured with capacitance type displacement probes. Random vibrations were applied by means of a large electrodynamic shaker at input levels ranging between 0.5 g (rms) and 1.5 g (rms). Vibrations were applied both along and perpendicular to the rotor axis. Response measurements were analyzed for amplitude distribution and power spectral density. Experimental results compare well with calculations of amplitude power spectral density made for the case where the vibrations were applied along the rotor axis. In this case, the rotor-bearing system was treated as a linear, three-mass model.

  14. [Effect of External Applying Compound Tripterygium wilfordii Hook F. on Joint Pain of Rheumatoid Arthritis Patients].

    PubMed

    Jiao, Juan; Tang, Xiao-po; Yuan, Jing; Liu, Xu; Liu, Hui; Zhang, Chun-yan; Wang, Li-ying; Jiang, Quan

    2016-01-01

    To observe the effectiveness and safety of external applying Compound Tripterygium wilfordii Hook F. (TwHF) in relieving joint pain in rheumatoid arthritis (RA) patients. In this double-blinded, randomized multicenter trial, a total of 174 moderately active RA patients were enrolled and randomly assigned to the treatment group (treated with Compound TwHF, 87 cases) and the placebo control group (87 cases). Compound TwHF or placebo was externally applied in painful joints, 20 g each time, once per day for 8 weeks. Self-reported joint pain relief was taken as a primary effective indicator. Visual analogue scale for pain (VAS), disease activity score of 28 joints (DAS28), VAS for general health (GH) were evaluated before treatment, at week 4 and after treatment. Erythrocyte sedimentation rate (ESR) and hypersensitive C reactive protein (hs-CRP) were tested before and after treatment. Menstrual changes in females were observed during treatment. Skin irritation occurred during the recording process was assessed using skin irritation strength. Intention to treat (ITT) was statistically analyzed. The joint pain relief rate in the treatment group was 90.8% (79/87 cases), higher than that in the placebo control group (69.0%, 60/87 cases; P = 0.001). VAS pain score, DAS28, VAS for GH score were significantly improved in the two groups at week 4 of treatment and after treatment, as compared with before treatment (P < 0.01). ESR and hs-CRP levels significantly decreased in the treatment group after treatment (P < 0.05, P < 0.01). No difference was found in post-treatment VAS pain score, DAS28, VAS for GH score, ESR, or hs-CRP between the two groups (P > 0.05). Eight adverse events occurred in the treatment group (5 skin allergy, 1 intolerance of medical odor, and 2 mild liver injury), while 3 adverse events occurred in the placebo control group (2 skin allergy, 1 mild liver injury). There was no statistical difference in adverse event between the two groups (P > 0.05). No menstrual change occurred in the treatment group. External applying Compound TwHF was an effective and safe way to relieve-joint pain of RA patients, which could be taken as an adjuvant therapy.

  15. Studies on energy transfer in dendrimer supermolecule using classical random walk model and Eyring model

    NASA Astrophysics Data System (ADS)

    Rana, Dipankar; Gangopadhyay, Gautam

    2003-01-01

    We have analyzed the energy transfer process in a dendrimer supermolecule using a classical random walk model and an Eyring model of membrane permeation. Here the energy transfer is considered as a multiple barrier crossing process by thermal hopping on the backbone of a cayley tree. It is shown that the mean residence time and mean first passage time, which involve explicit local escape rates, depend upon the temperature, size of the molecule, core branching, and the nature of the potential energy landscape along the cayley tree architecture. The effect of branching tries to create a uniform distribution of mean residence time over the generations and the distribution depends upon the interplay of funneling and local rates of transitions. The calculation of flux at the steady state from the Eyring model also gives a useful idea about the rate when the dendrimeric system is considered as an open system where the core is absorbing the transported energy like a photosynthetic reaction center and a continuous supply of external energy is maintained at the peripheral nodes. The effect of the above parameters of the system are shown to depend on the steady-state flux that has a qualitative resemblence with the result of the mean first passage time approach.

  16. How does context affect intimate relationships? linking external stress and cognitive processes within marriage.

    PubMed

    Neff, Lisa A; Karney, Benjamin R

    2004-02-01

    Stressors external to the marriage frequently affect the way spouses evaluate their marital quality. To date, however, understanding of the interplay between external stress and internal relationship processes has been limited in two ways. First, research has generally examined only the short-term consequences of stress. Second, the mechanisms through which external stressors influence relationship outcomes are unclear. This study addressed both limitations by examining relationship cognitions that may mediate the effects of external stress throughout 4 years of marriage. Analyses confirmed that stressful experiences were associated with the trajectory of marital quality overtime. Furthermore, both the content and the organization of spouses' specific relationship cognitions mediated this effect. That is, stress negatively influenced the nature of spouses' marital perceptions as well as the way spouses interpreted and processed those perceptions. These findings draw attention to ways that the context of relationships shapes and constrains relationship processes.

  17. Comparing Sensory Information Processing and Alexithymia between People with Substance Dependency and Normal.

    PubMed

    Bashapoor, Sajjad; Hosseini-Kiasari, Seyyedeh Tayebeh; Daneshvar, Somayeh; Kazemi-Taskooh, Zeinab

    2015-01-01

    Sensory information processing and alexithymia are two important factors in determining behavioral reactions. Some studies explain the effect of the sensitivity of sensory processing and alexithymia in the tendency to substance abuse. Giving that, the aim of the current study was to compare the styles of sensory information processing and alexithymia between substance-dependent people and normal ones. The research method was cross-sectional and the statistical population of the current study comprised of all substance-dependent men who are present in substance quitting camps of Masal, Iran, in October 2013 (n = 78). 36 persons were selected randomly by simple randomly sampling method from this population as the study group, and 36 persons were also selected among the normal population in the same way as the comparison group. Both groups was evaluated by using Toronto alexithymia scale (TAS) and adult sensory profile, and the multivariate analysis of variance (MANOVA) test was applied to analyze data. The results showed that there are significance differences between two groups in low registration (P < 0.020, F = 5.66), sensation seeking (P < 0.050, F = 1.92), and sensory avoidance (P < 0.008, F = 7.52) as a components of sensory processing and difficulty in describing emotions (P < 0.001, F = 15.01) and difficulty in identifying emotions (P < 0.002, F = 10.54) as a components of alexithymia. However, no significant difference were found between two groups in components of sensory sensitivity (P < 0.170, F = 1.92) and external oriented thinking style (P < 0.060, F = 3.60). These results showed that substance-dependent people process sensory information in a different way than normal people and show more alexithymia features than them.

  18. Comparing Sensory Information Processing and Alexithymia between People with Substance Dependency and Normal

    PubMed Central

    Bashapoor, Sajjad; Hosseini-Kiasari, Seyyedeh Tayebeh; Daneshvar, Somayeh; Kazemi-Taskooh, Zeinab

    2015-01-01

    Background Sensory information processing and alexithymia are two important factors in determining behavioral reactions. Some studies explain the effect of the sensitivity of sensory processing and alexithymia in the tendency to substance abuse. Giving that, the aim of the current study was to compare the styles of sensory information processing and alexithymia between substance-dependent people and normal ones. Methods The research method was cross-sectional and the statistical population of the current study comprised of all substance-dependent men who are present in substance quitting camps of Masal, Iran, in October 2013 (n = 78). 36 persons were selected randomly by simple randomly sampling method from this population as the study group, and 36 persons were also selected among the normal population in the same way as the comparison group. Both groups was evaluated by using Toronto alexithymia scale (TAS) and adult sensory profile, and the multivariate analysis of variance (MANOVA) test was applied to analyze data. Findings The results showed that there are significance differences between two groups in low registration (P < 0.020, F = 5.66), sensation seeking (P < 0.050, F = 1.92), and sensory avoidance (P < 0.008, F = 7.52) as a components of sensory processing and difficulty in describing emotions (P < 0.001, F = 15.01) and difficulty in identifying emotions (P < 0.002, F = 10.54) as a components of alexithymia. However, no significant difference were found between two groups in components of sensory sensitivity (P < 0.170, F = 1.92) and external oriented thinking style (P < 0.060, F = 3.60). Conclusion These results showed that substance-dependent people process sensory information in a different way than normal people and show more alexithymia features than them. PMID:26885354

  19. A Randomized Controlled Trial of the First Step to Success Early Intervention: Demonstration of Program Efficacy Outcomes in a Diverse, Urban School District

    ERIC Educational Resources Information Center

    Walker, Hill M.; Seeley, John R.; Small, Jason; Severson, Herbert H.; Graham, Bethany A.; Feil, Edward G.; Serna, Loretta; Golly, Annemieke M.; Forness, Steven R.

    2009-01-01

    This article reports on a randomized controlled trial of the First Step to Success early intervention that was conducted over a 4-year period in Albuquerque Public Schools. First Step is a selected intervention for students in Grades 1 through 3 with externalizing behavior problems, and it addresses secondary prevention goals and objectives. It…

  20. Long-Term Effects of a Universal Family Intervention: Mediation Through Parent-Adolescent Conflict

    PubMed Central

    Jensen, M.; Wong, J.J.; Gonzales, N.A.; Dumka, L.E.; Millsap, R.; Coxe, S.

    2014-01-01

    Objective This randomized trial of a family-focused preventive intervention for Mexican American middle schoolers examined internalizing, externalizing, and substance use outcomes in late adolescence, five years after completing the intervention. Parent-adolescent conflict was tested as a mediator of these effects. The role of parent and adolescent acculturation in these pathways was also examined. Method 498 7th grade adolescents and their primary female caregivers were randomized to receive either a 9-week, multi-component intervention or a brief workshop control group. Assessments were conducted at pre-test, two year follow-up (9th grade), and five year follow-up (when most participants were in the 12th grade). Results The Bridges program significantly reduced mother-adolescent conflict measured in the 9th grade, with conflict mediating program effects on internalizing and externalizing symptoms, adolescent substance use, and diagnosed internalizing disorder in late adolescence. Mother and child acculturation were both significantly predictive of late adolescence outcomes. Contrary to hypotheses, neither mother nor child acculturation emerged as a significant predictor of mother-adolescent conflict, and the interaction of mother and adolescent acculturation was similarly not related to mother-adolescent conflict. Intervention effects were largely consistent across different levels of acculturation. Conclusions These findings provide support for the efficacy of family-focused intervention during early adolescence, both in reducing mental health problems and substance use in the long term, as well as in impacting parent-adolescent conflict processes that appear to play an important role in the development of later adjustment problems. PMID:24730357

  1. Dynamics of comb-of-comb-network polymers in random layered flows

    NASA Astrophysics Data System (ADS)

    Katyal, Divya; Kant, Rama

    2016-12-01

    We analyze the dynamics of comb-of-comb-network polymers in the presence of external random flows. The dynamics of such structures is evaluated through relevant physical quantities, viz., average square displacement (ASD) and the velocity autocorrelation function (VACF). We focus on comparing the dynamics of the comb-of-comb network with the linear polymer. The present work displays an anomalous diffusive behavior of this flexible network in the random layered flows. The effect of the polymer topology on the dynamics is analyzed by varying the number of generations and branch lengths in these networks. In addition, we investigate the influence of external flow on the dynamics by varying flow parameters, like the flow exponent α and flow strength Wα. Our analysis highlights two anomalous power-law regimes, viz., subdiffusive (intermediate-time polymer stretching and flow-induced diffusion) and superdiffusive (long-time flow-induced diffusion). The anomalous long-time dynamics is governed by the temporal exponent ν of ASD, viz., ν =2 -α /2 . Compared to a linear polymer, the comb-of-comb network shows a shorter crossover time (from the subdiffusive to superdiffusive regime) but a reduced magnitude of ASD. Our theory displays an anomalous VACF in the random layered flows that scales as t-α /2. We show that the network with greater total mass moves faster.

  2. A randomized control trial evaluating fluorescent ink versus dark ink tattoos for breast radiotherapy

    PubMed Central

    Kirby, Anna M; Lee, Steven F; Bartlett, Freddie; Titmarsh, Kumud; Donovan, Ellen; Griffin, Clare L; Gothard, Lone; Locke, Imogen; McNair, Helen A

    2016-01-01

    Objective: The purpose of this UK study was to evaluate interfraction reproducibility and body image score when using ultraviolet (UV) tattoos (not visible in ambient lighting) for external references during breast/chest wall radiotherapy and compare with conventional dark ink. Methods: In this non-blinded, single-centre, parallel group, randomized control trial, patients were allocated to receive either conventional dark ink or UV ink tattoos using computer-generated random blocks. Participant assignment was not masked. Systematic (∑) and random (σ) setup errors were determined using electronic portal images. Body image questionnaires were completed at pre-treatment, 1 month and 6 months to determine the impact of tattoo type on body image. The primary end point was to determine that UV tattoo random error (σsetup) was no less accurate than with conventional dark ink tattoos, i.e. <2.8 mm. Results: 46 patients were randomized to receive conventional dark or UV ink tattoos. 45 patients completed treatment (UV: n = 23, dark: n = 22). σsetup for the UV tattoo group was <2.8 mm in the u and v directions (p = 0.001 and p = 0.009, respectively). A larger proportion of patients reported improvement in body image score in the UV tattoo group compared with the dark ink group at 1 month [56% (13/23) vs 14% (3/22), respectively] and 6 months [52% (11/21) vs 38% (8/21), respectively]. Conclusion: UV tattoos were associated with interfraction setup reproducibility comparable with conventional dark ink. Patients reported a more favourable change in body image score up to 6 months following treatment. Advances in knowledge: This study is the first to evaluate UV tattoo external references in a randomized control trial. PMID:27710100

  3. A randomized control trial evaluating fluorescent ink versus dark ink tattoos for breast radiotherapy.

    PubMed

    Landeg, Steven J; Kirby, Anna M; Lee, Steven F; Bartlett, Freddie; Titmarsh, Kumud; Donovan, Ellen; Griffin, Clare L; Gothard, Lone; Locke, Imogen; McNair, Helen A

    2016-12-01

    The purpose of this UK study was to evaluate interfraction reproducibility and body image score when using ultraviolet (UV) tattoos (not visible in ambient lighting) for external references during breast/chest wall radiotherapy and compare with conventional dark ink. In this non-blinded, single-centre, parallel group, randomized control trial, patients were allocated to receive either conventional dark ink or UV ink tattoos using computer-generated random blocks. Participant assignment was not masked. Systematic (∑) and random (σ) setup errors were determined using electronic portal images. Body image questionnaires were completed at pre-treatment, 1 month and 6 months to determine the impact of tattoo type on body image. The primary end point was to determine that UV tattoo random error (σ setup ) was no less accurate than with conventional dark ink tattoos, i.e. <2.8 mm. 46 patients were randomized to receive conventional dark or UV ink tattoos. 45 patients completed treatment (UV: n = 23, dark: n = 22). σ setup for the UV tattoo group was <2.8 mm in the u and v directions (p = 0.001 and p = 0.009, respectively). A larger proportion of patients reported improvement in body image score in the UV tattoo group compared with the dark ink group at 1 month [56% (13/23) vs 14% (3/22), respectively] and 6 months [52% (11/21) vs 38% (8/21), respectively]. UV tattoos were associated with interfraction setup reproducibility comparable with conventional dark ink. Patients reported a more favourable change in body image score up to 6 months following treatment. Advances in knowledge: This study is the first to evaluate UV tattoo external references in a randomized control trial.

  4. Person mobility in the design and analysis of cluster-randomized cohort prevention trials.

    PubMed

    Vuchinich, Sam; Flay, Brian R; Aber, Lawrence; Bickman, Leonard

    2012-06-01

    Person mobility is an inescapable fact of life for most cluster-randomized (e.g., schools, hospitals, clinic, cities, state) cohort prevention trials. Mobility rates are an important substantive consideration in estimating the effects of an intervention. In cluster-randomized trials, mobility rates are often correlated with ethnicity, poverty and other variables associated with disparity. This raises the possibility that estimated intervention effects may generalize to only the least mobile segments of a population and, thus, create a threat to external validity. Such mobility can also create threats to the internal validity of conclusions from randomized trials. Researchers must decide how to deal with persons who leave study clusters during a trial (dropouts), persons and clusters that do not comply with an assigned intervention, and persons who enter clusters during a trial (late entrants), in addition to the persons who remain for the duration of a trial (stayers). Statistical techniques alone cannot solve the key issues of internal and external validity raised by the phenomenon of person mobility. This commentary presents a systematic, Campbellian-type analysis of person mobility in cluster-randomized cohort prevention trials. It describes four approaches for dealing with dropouts, late entrants and stayers with respect to data collection, analysis and generalizability. The questions at issue are: 1) From whom should data be collected at each wave of data collection? 2) Which cases should be included in the analyses of an intervention effect? and 3) To what populations can trial results be generalized? The conclusions lead to recommendations for the design and analysis of future cluster-randomized cohort prevention trials.

  5. Fast counting electronics for neutron coincidence counting

    DOEpatents

    Swansen, James E.

    1987-01-01

    An amplifier-discriminator is tailored to output a very short pulse upon an above-threshold input from a detector which may be a .sup.3 He detector. The short pulse output is stretched and energizes a light emitting diode (LED) to provide a visual output of operation and pulse detection. The short pulse is further fed to a digital section for processing and possible ORing with other like generated pulses. Finally, the output (or ORed output ) is fed to a derandomizing buffer which converts the rapidly and randomly occurring pulses into synchronized and periodically spaced-apart pulses for the accurate counting thereof. Provision is also made for the internal and external disabling of each individual channel of amplifier-discriminators in an ORed plurality of same.

  6. Fast counting electronics for neutron coincidence counting

    DOEpatents

    Swansen, J.E.

    1985-03-05

    An amplifier-discriminator is tailored to output a very short pulse upon an above-threshold input from a detector which may be a /sup 3/He detector. The short pulse output is stretched and energizes a light emitting diode (LED) to provide a visual output of operation and pulse detection. The short pulse is further fed to a digital section for processing and possible ORing with other like generated pulses. Finally, the output (or ORed output) is fed to a derandomizing buffer which converts the rapidly and randomly occurring pulses into synchronized and periodically spaced-apart pulses for the accurate counting thereof. Provision is also made for the internal and external disabling of each individual channel of amplifier-discriminators in an ORed plurality of same.

  7. Dimensionality and entropy of spontaneous and evoked rate activity

    NASA Astrophysics Data System (ADS)

    Engelken, Rainer; Wolf, Fred

    Cortical circuits exhibit complex activity patterns both spontaneously and evoked by external stimuli. Finding low-dimensional structure in population activity is a challenge. What is the diversity of the collective neural activity and how is it affected by an external stimulus? Using concepts from ergodic theory, we calculate the attractor dimensionality and dynamical entropy production of these networks. We obtain these two canonical measures of the collective network dynamics from the full set of Lyapunov exponents. We consider a randomly-wired firing-rate network that exhibits chaotic rate fluctuations for sufficiently strong synaptic weights. We show that dynamical entropy scales logarithmically with synaptic coupling strength, while the attractor dimensionality saturates. Thus, despite the increasing uncertainty, the diversity of collective activity saturates for strong coupling. We find that a time-varying external stimulus drastically reduces both entropy and dimensionality. Finally, we analytically approximate the full Lyapunov spectrum in several limiting cases by random matrix theory. Our study opens a novel avenue to characterize the complex dynamics of rate networks and the geometric structure of the corresponding high-dimensional chaotic attractor. received funding from Evangelisches Studienwerk Villigst, DFG through CRC 889 and Volkswagen Foundation.

  8. Influence of anisotropy on percolation and jamming of linear k-mers on square lattice with defects

    NASA Astrophysics Data System (ADS)

    Tarasevich, Yu Yu; Laptev, V. V.; Burmistrov, A. S.; Shinyaeva, T. S.

    2015-09-01

    By means of the Monte Carlo simulation, we study the layers produced by the random sequential adsorption of the linear rigid objects (k-mers also known as rigid or stiff rods, sticks, needles) onto the square lattice with defects in the presence of an external field. The value of k varies from 2 to 32. The point defects randomly and uniformly placed on the substrate hinder adsorption of the elongated objects. The external field affects isotropic deposition of the particles, consequently the deposited layers are anisotropic. We study the influence of the defect concentration, the length of the objects, and the external field on the percolation threshold and the jamming concentration. Our main findings are (i) the critical defect concentration at which the percolation never occurs even at jammed state decreases for short k-mers (k < 16) and increases for long k-mers (k > 16) as anisotropy increases, (ii) the corresponding critical k-mer concentration decreases with anisotropy growth, (iii) the jamming concentration decreases drastically with growth of k-mer length for any anisotropy, (iv) for short k-mers, the percolation threshold is almost insensitive to the defect concentration for any anisotropy.

  9. Numerical simulation of a helical shape electric arc in the external axial magnetic field

    NASA Astrophysics Data System (ADS)

    Urusov, R. M.; Urusova, I. R.

    2016-10-01

    Within the frameworks of non-stationary three-dimensional mathematical model, in approximation of a partial local thermodynamic equilibrium, a numerical calculation was made of characteristics of DC electric arc burning in a cylindrical channel in the uniform external axial magnetic field. The method of numerical simulation of the arc of helical shape in a uniform external axial magnetic field was proposed. This method consists in that that in the computational algorithm, a "scheme" analog of fluctuations for electrons temperature is supplemented. The "scheme" analogue of fluctuations increases a weak numerical asymmetry of electrons temperature distribution, which occurs randomly in the course of computing. This asymmetry can be "picked up" by the external magnetic field that continues to increase up to a certain value, which is sufficient for the formation of helical structure of the arc column. In the absence of fluctuations in the computational algorithm, the arc column in the external axial magnetic field maintains cylindrical axial symmetry, and a helical form of the arc is not observed.

  10. Radiotherapy in poor risk patients with stage I cancer of the endometrium: results of not giving external beam radiotherapy.

    PubMed

    DeCruze, B; Guthrie, D

    1999-01-01

    Poor prognosis (poorly differentiated and/or deep myometrial invasion) Stage I endometrial cancer can have a relapse rate as high as 50%. Traditionally, most clinical oncologists treat these patients with external beam radiotherapy after surgery but there is no evidence to show that this improves survival. The retrospective study looks at the results of not giving external beam radiotherapy in 25 consecutive patients and compares the results with a group of 13 consecutive patients who did have such treatment. The two groups were comparable with regard to age, degree of differentiation and degree of invasion. Survival was comparable in the two groups. There is no evidence of any obvious decrease in survival from withholding external beam radiotherapy, but this was not a prospective randomized controlled trial. This study illustrates that it is essential that the Medical Research Council ASTEC trial should be supported because this will determine the true place of external beam radiotherapy in such patients.

  11. Gaps between avalanches in one-dimensional random-field Ising models

    NASA Astrophysics Data System (ADS)

    Nampoothiri, Jishnu N.; Ramola, Kabir; Sabhapandit, Sanjib; Chakraborty, Bulbul

    2017-09-01

    We analyze the statistics of gaps (Δ H ) between successive avalanches in one-dimensional random-field Ising models (RFIMs) in an external field H at zero temperature. In the first part of the paper we study the nearest-neighbor ferromagnetic RFIM. We map the sequence of avalanches in this system to a nonhomogeneous Poisson process with an H -dependent rate ρ (H ) . We use this to analytically compute the distribution of gaps P (Δ H ) between avalanches as the field is increased monotonically from -∞ to +∞ . We show that P (Δ H ) tends to a constant C (R ) as Δ H →0+ , which displays a nontrivial behavior with the strength of disorder R . We verify our predictions with numerical simulations. In the second part of the paper, motivated by avalanche gap distributions in driven disordered amorphous solids, we study a long-range antiferromagnetic RFIM. This model displays a gapped behavior P (Δ H )=0 up to a system size dependent offset value Δ Hoff , and P (Δ H ) ˜(ΔH -Δ Hoff) θ as Δ H →Hoff+ . We perform numerical simulations on this model and determine θ ≈0.95 (5 ) . We also discuss mechanisms which would lead to a nonzero exponent θ for general spin models with quenched random fields.

  12. Mitigating stimulated scattering processes in gas-filled Hohlraums via external magnetic fields

    NASA Astrophysics Data System (ADS)

    Gong, Tao; Zheng, Jian; Li, Zhichao; Ding, Yongkun; Yang, Dong; Hu, Guangyue; Zhao, Bin

    2015-09-01

    A simple model, based on energy and pressure equilibrium, is proposed to deal with the effect of external magnetic fields on the plasma parameters inside the laser path, which shows that the electron temperature can be significantly enhanced as the intensity of the external magnetic fields increases. With the combination of this model and a 1D three-wave coupling code, the effect of external magnetic fields on the reflectivities of stimulated scattering processes is studied. The results indicate that a magnetic field with an intensity of tens of Tesla can decrease the reflectivities of stimulated scattering processes by several orders of magnitude.

  13. Cognitive effects of rhythmic auditory stimulation in Parkinson's disease: A P300 study.

    PubMed

    Lei, Juan; Conradi, Nadine; Abel, Cornelius; Frisch, Stefan; Brodski-Guerniero, Alla; Hildner, Marcel; Kell, Christian A; Kaiser, Jochen; Schmidt-Kassow, Maren

    2018-05-16

    Rhythmic auditory stimulation (RAS) may compensate dysfunctions of the basal ganglia (BG), involved with intrinsic evaluation of temporal intervals and action initiation or continuation. In the cognitive domain, RAS containing periodically presented tones facilitates young healthy participants' attention allocation to anticipated time points, indicated by better performance and larger P300 amplitudes to periodic compared to random stimuli. Additionally, active auditory-motor synchronization (AMS) leads to a more precise temporal encoding of stimuli via embodied timing encoding than stimulus presentation adapted to the participants' actual movements. Here we investigated the effect of RAS and AMS in Parkinson's disease (PD). 23 PD patients and 23 healthy age-matched controls underwent an auditory oddball task. We manipulated the timing (periodic/random/adaptive) and setting (pedaling/sitting still) of stimulation. While patients elicited a general timing effect, i.e., larger P300 amplitudes for periodic versus random tones for both, sitting and pedaling conditions, controls showed a timing effect only for the sitting but not for the pedaling condition. However, a correlation between P300 amplitudes and motor variability in the periodic pedaling condition was obtained in control participants only. We conclude that RAS facilitates attentional processing of temporally predictable external events in PD patients as well as healthy controls, but embodied timing encoding via body movement does not affect stimulus processing due to BG impairment in patients. Moreover, even with intact embodied timing encoding, such as healthy elderly, the effect of AMS depends on the degree of movement synchronization performance, which is very low in the current study. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Natural Memory Beyond the Storage Model: Repression, Trauma, and the Construction of a Personal Past

    PubMed Central

    Axmacher, Nikolai; Do Lam, Anne T. A.; Kessler, Henrik; Fell, Juergen

    2010-01-01

    Naturally occurring memory processes show features which are difficult to investigate by conventional cognitive neuroscience paradigms. Distortions of memory for problematic contents are described both by psychoanalysis (internal conflicts) and research on post-traumatic stress disorder (PTSD; external traumata). Typically, declarative memory for these contents is impaired – possibly due to repression in the case of internal conflicts or due to dissociation in the case of external traumata – but they continue to exert an unconscious pathological influence: neurotic symptoms or psychosomatic disorders after repression or flashbacks and intrusions in PTSD after dissociation. Several experimental paradigms aim at investigating repression in healthy control subjects. We argue that these paradigms do not adequately operationalize the clinical process of repression, because they rely on an intentional inhibition of random stimuli (suppression). Furthermore, these paradigms ignore that memory distortions due to repression or dissociation are most accurately characterized by a lack of self-referential processing, resulting in an impaired integration of these contents into the self. This aspect of repression and dissociation cannot be captured by the concept of memory as a storage device which is usually employed in the cognitive neurosciences. It can only be assessed within the framework of a constructivist memory concept, according to which successful memory involves a reconstruction of experiences such that they fit into a representation of the self. We suggest several experimental paradigms that allow for the investigation of the neural correlates of repressed memories and trauma-induced memory distortions based on a constructivist memory concept. PMID:21151366

  15. Analytical and Experimental Random Vibration of Nonlinear Aeroelastic Structures.

    DTIC Science & Technology

    1987-01-28

    firstorder differential equations. In view of the system complexi- ty an attempt s made to close the infinite hierarchy by using a Gaussian scheme. This sc...year of this project-. When the first normal mode is externally excited by a band-limited random excitation, the system mean square response is found...governed mainly by the internal detuning parameter and the system damping ratios. The results are completely different when the second normal mode is

  16. Serotonin Transporter Genotype (5HTTLPR) Moderates the Longitudinal Impact of Atypical Attachment on Externalizing Behavior.

    PubMed

    Humphreys, Kathryn L; Zeanah, Charles H; Nelson, Charles A; Fox, Nathan A; Drury, Stacy S

    2015-01-01

    To test whether genotype of the serotonin transporter-linked polymorphic region (5HTTLPR) and atypical attachment interact to predict externalizing psychopathology prospectively in a sample of children with a history of early institutional care. Caregiver report of externalizing behavior at 54 months was examined in 105 children initially reared in institutional care and enrolled in the Bucharest Early Intervention Project, a randomized controlled trial of high quality foster care. 5HTTLPR genotype, attachment status at 42 months of age (typical [secure, avoidant, or ambivalent] or atypical [disorganized-controlling, insecure-other]), and their interaction were examined as predictors of externalizing behavior at age 54 months. 5HTTLPR genotype and atypical attachment at age 42 months interacted to predict externalizing behavior at age 54 months. Specifically, children with the s/s genotype with an atypical attachment had the highest externalizing scores. However, s/s children with a typical attachment demonstrated the lowest externalizing scores, even after controlling for intervention group status. There was no association between attachment status and externalizing behavior among children carrying at least 1 copy of the l allele. These findings indicate that genetic variation in the serotonergic system moderates the association between atypical attachment status and externalizing in young children. Our findings suggest that children, as a result of genetic variability in the serotonergic system, demonstrate differential sensitivity to the attachment relationship.

  17. Serotonin Transporter Genotype (5HTTLPR) Moderates the Longitudinal Impact of Atypical Attachment on Externalizing Behavior

    PubMed Central

    Humphreys, Kathryn L.; Zeanah, Charles H.; Nelson, Charles A.; Fox, Nathan A.; Drury, Stacy S.

    2015-01-01

    Objective To test whether genotype of the serotonin transporter-linked polymorphic region (5HTTLPR) and atypical attachment interact to predict externalizing psychopathology prospectively in a sample of children with a history of early institutional care. Methods Caregiver report of externalizing behavior at 54 months was examined in 105 children initially reared in institutional care and enrolled in the Bucharest Early Intervention Project, a randomized controlled trial of high quality foster care. 5HTTLPR genotype, attachment status at 42 months of age (typical [secure, avoidant, or ambivalent] or atypical [disorganized-controlling, insecure-other]), as well as their interaction, were examined as predictors of externalizing behavior at age 54 months. Results 5HTTLPR genotype and atypical attachment at age 42 months interacted to predict externalizing behavior at age 54 months. Specifically, children with the s/s genotype with an atypical attachment had the highest externalizing scores. However, s/s children with a typical attachment demonstrated the lowest externalizing scores, even after controlling for intervention group status. There was no association between attachment status and externalizing behavior among children carrying at least one copy of the l allele. Discussion These findings indicate that genetic variation in the serotonergic system moderates the association between atypical attachment status and externalizing in young children. Our findings suggest that children, as a result of genetic variability in the serotonergic system, demonstrate differential sensitivity to the attachment relationship. PMID:25933228

  18. Prefrontal Cortex Networks Shift from External to Internal Modes during Learning.

    PubMed

    Brincat, Scott L; Miller, Earl K

    2016-09-14

    As we learn about items in our environment, their neural representations become increasingly enriched with our acquired knowledge. But there is little understanding of how network dynamics and neural processing related to external information changes as it becomes laden with "internal" memories. We sampled spiking and local field potential activity simultaneously from multiple sites in the lateral prefrontal cortex (PFC) and the hippocampus (HPC)-regions critical for sensory associations-of monkeys performing an object paired-associate learning task. We found that in the PFC, evoked potentials to, and neural information about, external sensory stimulation decreased while induced beta-band (∼11-27 Hz) oscillatory power and synchrony associated with "top-down" or internal processing increased. By contrast, the HPC showed little evidence of learning-related changes in either spiking activity or network dynamics. The results suggest that during associative learning, PFC networks shift their resources from external to internal processing. As we learn about items in our environment, their representations in our brain become increasingly enriched with our acquired "top-down" knowledge. We found that in the prefrontal cortex, but not the hippocampus, processing of external sensory inputs decreased while internal network dynamics related to top-down processing increased. The results suggest that during learning, prefrontal cortex networks shift their resources from external (sensory) to internal (memory) processing. Copyright © 2016 the authors 0270-6474/16/369739-16$15.00/0.

  19. Prefrontal Cortex Networks Shift from External to Internal Modes during Learning

    PubMed Central

    Brincat, Scott L.

    2016-01-01

    As we learn about items in our environment, their neural representations become increasingly enriched with our acquired knowledge. But there is little understanding of how network dynamics and neural processing related to external information changes as it becomes laden with “internal” memories. We sampled spiking and local field potential activity simultaneously from multiple sites in the lateral prefrontal cortex (PFC) and the hippocampus (HPC)—regions critical for sensory associations—of monkeys performing an object paired-associate learning task. We found that in the PFC, evoked potentials to, and neural information about, external sensory stimulation decreased while induced beta-band (∼11–27 Hz) oscillatory power and synchrony associated with “top-down” or internal processing increased. By contrast, the HPC showed little evidence of learning-related changes in either spiking activity or network dynamics. The results suggest that during associative learning, PFC networks shift their resources from external to internal processing. SIGNIFICANCE STATEMENT As we learn about items in our environment, their representations in our brain become increasingly enriched with our acquired “top-down” knowledge. We found that in the prefrontal cortex, but not the hippocampus, processing of external sensory inputs decreased while internal network dynamics related to top-down processing increased. The results suggest that during learning, prefrontal cortex networks shift their resources from external (sensory) to internal (memory) processing. PMID:27629722

  20. Temperature sequence of eggs from oviposition through distribution: processing--part 2.

    PubMed

    Koelkebeck, K W; Patterson, P H; Anderson, K E; Darre, M J; Carey, J B; Ahn, D U; Ernst, R A; Kuney, D R; Jones, D

    2008-06-01

    The Egg Safety Action Plan released in 1999 raised questions concerning egg temperature used in the risk assessment model. Therefore, a national study was initiated to determine the internal and external temperature sequence of eggs from oviposition through distribution. Researchers gathered data from commercial egg production, shell egg processing, and distribution facilities. The experimental design was a mixed model with 2 random effects for season and geographic region and a fixed effect for operation type (inline or offline). For this report, internal and external egg temperature data were recorded at specific points during shell egg processing in the winter and summer months. In addition, internal egg temperatures were recorded in pre- and postshell egg processing cooler areas. There was a significant season x geographic region interaction (P < 0.05) for both surface and internal temperatures. Egg temperatures were lower in the winter vs. summer, but eggs gained in temperature from the accumulator to the postshell egg processing cooler. During shell egg processing, summer egg surface and internal temperatures were greater (P < 0.05) than during the winter. When examining the effect of shell egg processing time and conditions, it was found that 2.4 and 3.8 degrees C were added to egg surface temperatures, and 3.3 and 6.0 degrees C were added to internal temperatures in the summer and winter, respectively. Internal egg temperatures were higher (P < 0.05) in the preshell egg processing cooler area during the summer vs. winter, and internal egg temperatures were higher (P < 0.05) in the summer when eggs were (3/4) cool (temperature change required to meet USDA-Agricultural Marketing Service storage regulation of 7.2 degrees C) in the postshell egg processing area. However, the cooling rate was not different (P > 0.05) for eggs in the postshell egg processing cooler area in the summer vs. winter. Therefore, these data suggest that season of year and geographic location can affect the temperature of eggs during shell egg processing and should be a component in future assessments of egg safety.

  1. Stationary responses of a Rayleigh viscoelastic system with zero barrier impacts under external random excitation.

    PubMed

    Wang, Deli; Xu, Wei; Zhao, Xiangrong

    2016-03-01

    This paper aims to deal with the stationary responses of a Rayleigh viscoelastic system with zero barrier impacts under external random excitation. First, the original stochastic viscoelastic system is converted to an equivalent stochastic system without viscoelastic terms by approximately adding the equivalent stiffness and damping. Relying on the means of non-smooth transformation of state variables, the above system is replaced by a new system without an impact term. Then, the stationary probability density functions of the system are observed analytically through stochastic averaging method. By considering the effects of the biquadratic nonlinear damping coefficient and the noise intensity on the system responses, the effectiveness of the theoretical method is tested by comparing the analytical results with those generated from Monte Carlo simulations. Additionally, it does deserve attention that some system parameters can induce the occurrence of stochastic P-bifurcation.

  2. A Randomized Controlled Trial of Familias Unidas for Hispanic Adolescents With Behavior Problems

    PubMed Central

    Pantin, Hilda; Prado, Guillermo; Lopez, Barbara; Huang, Shi; Tapia, Maria I.; Schwartz, Seth J.; Sabillon, Eduardo; Brown, C. Hendricks; Branchini, Jennifer

    2009-01-01

    Objective To evaluate the efficacy of Familias Unidas, a Hispanic-specific, parent-centered intervention, in preventing/reducing adolescent substance use, unsafe sexual behavior, and externalizing disorders. Methods A total of 213 8th grade Hispanic adolescents with behavior problems and their primary caregivers were assigned randomly to one of two conditions: Familias Unidas or Community Control. Participants were assessed at baseline and at 6, 18, and 30 months post baseline. Results Results showed that, relative to a Community Control condition, Familias Unidas was efficacious in preventing or reducing externalizing disorders, preventing and reducing substance use, and in reducing unsafe sexual behavior. The effects of Familias Unidas on these outcomes were partially mediated by improvements in family functioning. Conclusions These findings suggest that parent-centered intervention is an efficacious strategy for preventing/reducing specific health risk behaviors in Hispanic adolescents with behavior problems. PMID:19834053

  3. Integrating Comparative Effectiveness Design Elements and Endpoints Into a Phase III, Randomized Clinical Trial (SWOG S1007) Evaluating OncotypeDX-Guided Management for Women With Breast Cancer Involving Lymph Nodes

    PubMed Central

    Ramsey, Scott D.; Barlow, William E.; Gonzalez-Angulo, Ana M.; Tunis, Sean; Baker, Laurence; Crowley, John; Deverka, Patricia; Veenstra, David; Hortobagyi, Gabriel N.

    2012-01-01

    Women with breast cancer involving the lymph nodes are typically treated with cytotoxic chemotherapy. Retrospective evaluations of prior studies suggest that the 21-gene test (OncotypeDX®), may allow identification of those who can safely avoid chemotherapy. To better understand the performance of the 21-gene test, the RxPONDER (Rx for Positive Node, Endocrine Responsive breast cancer) study was designed, a multicenter Phase III trial randomizing women with hormone receptor-positive and HER2-negative breast cancer involving 1–3 lymph nodes and a 21-gene assay recurrence score (RS) of 25 or less to endocrine therapy alone versus chemotherapy followed by endocrine therapy. As one of the first large-scale comparative-effectiveness studies in oncology, RxPONDER utilized an external stakeholder group to help inform the design of the trial. Stakeholders met with representatives of SWOG over several months through a structured discussion process. The stakeholder engagement process resulted in several changes being made to the trial design. In addition, stakeholder representatives from the health insurance industry provided guidance regarding a mechanism whereby the costs of OncotypeDX® would be paid by the majority of health insurers as part of the trial. The process may serve as a template for future studies evaluating the comparative effectiveness of genomic tests in oncology, particularly those that are conducted within cooperative clinical trials groups. PMID:23000081

  4. Noisy oscillator: Random mass and random damping.

    PubMed

    Burov, Stanislav; Gitterman, Moshe

    2016-11-01

    The problem of a linear damped noisy oscillator is treated in the presence of two multiplicative sources of noise which imply a random mass and random damping. The additive noise and the noise in the damping are responsible for an influx of energy to the oscillator and its dissipation to the surrounding environment. A random mass implies that the surrounding molecules not only collide with the oscillator but may also adhere to it, thereby changing its mass. We present general formulas for the first two moments and address the question of mean and energetic stabilities. The phenomenon of stochastic resonance, i.e., the expansion due to the noise of a system response to an external periodic signal, is considered for separate and joint action of two sources of noise and their characteristics.

  5. Scanning transmission X-ray microscopy probe for in situ mechanism study of graphene-oxide-based resistive random access memory.

    PubMed

    Nho, Hyun Woo; Kim, Jong Yun; Wang, Jian; Shin, Hyun-Joon; Choi, Sung-Yool; Yoon, Tae Hyun

    2014-01-01

    Here, an in situ probe for scanning transmission X-ray microscopy (STXM) has been developed and applied to the study of the bipolar resistive switching (BRS) mechanism in an Al/graphene oxide (GO)/Al resistive random access memory (RRAM) device. To perform in situ STXM studies at the C K- and O K-edges, both the RRAM junctions and the I0 junction were fabricated on a single Si3N4 membrane to obtain local XANES spectra at these absorption edges with more delicate I0 normalization. Using this probe combined with the synchrotron-based STXM technique, it was possible to observe unique chemical changes involved in the BRS process of the Al/GO/Al RRAM device. Reversible oxidation and reduction of GO induced by the externally applied bias voltages were observed at the O K-edge XANES feature located at 538.2 eV, which strongly supported the oxygen ion drift model that was recently proposed from ex situ transmission electron microscope studies.

  6. Strengthening Causal Estimates for Links Between Spanking and Children's Externalizing Behavior Problems.

    PubMed

    Gershoff, Elizabeth T; Sattler, Kierra M P; Ansari, Arya

    2018-01-01

    Establishing causal links when experiments are not feasible is an important challenge for psychology researchers. The question of whether parents' spanking causes children's externalizing behavior problems poses such a challenge because randomized experiments of spanking are unethical, and correlational studies cannot rule out potential selection factors. This study used propensity score matching based on the lifetime prevalence and recent incidence of spanking in a large and nationally representative sample ( N = 12,112) as well as lagged dependent variables to get as close to causal estimates outside an experiment as possible. Whether children were spanked at the age of 5 years predicted increases in externalizing behavior problems by ages 6 and 8, even after the groups based on spanking prevalence or incidence were matched on a range of sociodemographic, family, and cultural characteristics and children's initial behavior problems. These statistically rigorous methods yield the conclusion that spanking predicts a deterioration of children's externalizing behavior over time.

  7. Efficacy test of a toothpaste in reducing extrinsic dental stain

    NASA Astrophysics Data System (ADS)

    Agustanti, A.; Ramadhani, S. A.; Adiatman, M.; Rahardjo, A.; Callea, M.; Yavuz, I.; Maharani, D. A.

    2017-08-01

    This clinical trial compared the external dental stain reduction achieved by tested toothpaste versus placebo in adult patients. In this double-blind, parallel, randomised clinical trial, 45 female volunteers with a mean age of 20 years old were included. All study subjects front teeth were topically applicated with Silver Diamine Fluoride (SDF) to create external dental stains. Subjects were randomized into test (n=22) and control (n=23) groups. Toothpastes were used for two days to analyse the effects of removing external stains on the labial surfaces of all anterior teeth. VITA Easyshade Advance 4.0 was used to measure dental extrinsic stains changes. The analysis showed statistically significant efficacy of the tested toothpaste in reducing external dental stain caused by SDF, comparing to the placebo toothpaste, after one and two days of usage. The tested toothpaste was effective in reducing dental stain.

  8. Phase 4 Studies in Heart Failure - What is Done and What is Needed?

    PubMed

    Iyngkaran, Pupalan; Liew, Danny; McDonald, Peter; Thomas, Merlin C; Reid, Christopher; Chew, Derek; Hare, David L

    Congestive heart failure (CHF) therapeutics is generated through a well-described evidence generating process. Phases 1 - 3 of this process are required prior to approval and widespread clinical use. Phase 3 in almost all cases is a methodologically sound randomized controlled trial (RCT). After this phase it is generally accepted that the treatment has a significant, independent and prognostically beneficial effect on the pathophysiological process. A major criticism of RCTs is the population to whom the result is applicable. When this population is significantly different from the trial cohort the external validity comes into question. Should the continuation of the evidence generating process continue these problems might be identified. Post marketing surveillance through phase 4 and comparative effectiveness studies through phase 5 trials are often underperformed in comparison to the RCT. These processes can help identify remote adverse events and define new hypotheses for community level benefits. This review is aimed at exploring the post-marketing scene for CHF therapeutics from an Australian health system perspective. We explore the phases of clinical trials, the level of evidence currently available and options for ensuring greater accountability for community level CHF clinical outcomes.

  9. Phase 4 Studies in Heart Failure - What is Done and What is Needed?

    PubMed Central

    Iyngkaran, Pupalan; Liew, Danny; McDonald, Peter; Thomas, Merlin C.; Reid, Christopher; Chew, Derek; Hare, David L.

    2016-01-01

    Congestive heart failure (CHF) therapeutics is generated through a well-described evidence generating process. Phases 1 – 3 of this process are required prior to approval and widespread clinical use. Phase 3 in almost all cases is a methodologically sound randomized controlled trial (RCT). After this phase it is generally accepted that the treatment has a significant, independent and prognostically beneficial effect on the pathophysiological process. A major criticism of RCTs is the population to whom the result is applicable. When this population is significantly different from the trial cohort the external validity comes into question. Should the continuation of the evidence generating process continue these problems might be identified. Post marketing surveillance through phase 4 and comparative effectiveness studies through phase 5 trials are often underperformed in comparison to the RCT. These processes can help identify remote adverse events and define new hypotheses for community level benefits. This review is aimed at exploring the post-marketing scene for CHF therapeutics from an Australian health system perspective. We explore the phases of clinical trials, the level of evidence currently available and options for ensuring greater accountability for community level CHF clinical outcomes. PMID:27280303

  10. Repair process and a repaired component

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Roberts, III, Herbert Chidsey; Simpson, Stanley F.

    Matrix composite component repair processes are disclosed. The matrix composite repair process includes applying a repair material to a matrix composite component, securing the repair material to the matrix composite component with an external securing mechanism and curing the repair material to bond the repair material to the matrix composite component during the securing by the external securing mechanism. The matrix composite component is selected from the group consisting of a ceramic matrix composite, a polymer matrix composite, and a metal matrix composite. In another embodiment, the repair process includes applying a partially-cured repair material to a matrix composite component,more » and curing the repair material to bond the repair material to the matrix composite component, an external securing mechanism securing the repair material throughout a curing period, In another embodiment, the external securing mechanism is consumed or decomposed during the repair process.« less

  11. Processing device with self-scrubbing logic

    DOEpatents

    Wojahn, Christopher K.

    2016-03-01

    An apparatus includes a processing unit including a configuration memory and self-scrubber logic coupled to read the configuration memory to detect compromised data stored in the configuration memory. The apparatus also includes a watchdog unit external to the processing unit and coupled to the self-scrubber logic to detect a failure in the self-scrubber logic. The watchdog unit is coupled to the processing unit to selectively reset the processing unit in response to detecting the failure in the self-scrubber logic. The apparatus also includes an external memory external to the processing unit and coupled to send configuration data to the configuration memory in response to a data feed signal outputted by the self-scrubber logic.

  12. Breaking the Silos: The art Documentation Suite

    NASA Astrophysics Data System (ADS)

    Kutschke, Robert K.

    2015-12-01

    The art event-processing framework is used by almost all new experiments at Fermilab, and by several outside of Fermilab. All use art as an external product in the same sense that the compiler, ROOT, Geant4, CLHEP and boost are external products. The art team has embarked on a campaign to document art and develop training materials for new users. Many new users of art have little or no knowledge of C++, software engineering, build systems or the many external packages used by art or their experiments, such as ROOT, CLHEP, HEPPDT, and boost. To effectively teach art requires that the training materials include appropriate introductions to these topics as they are encountered. Experience has shown that simply referring readers to the existing native documentation does not work; too often a simple idea that they need to understand is described in a context that presumes prerequisites that are unimportant for a beginning user of art. There is the additional complication that the training materials must be presented in a way that does not presume knowledge of any of the experiments using art. Finally, new users of art arrive at random times throughout the year and the training materials must allow them to start to learn art at any time. This presentation will explain the strategies adopted by the art team to develop a documentation suite that complies with these boundary conditions. It will also show the present status of the documentation suite, including feedback the art team has received from pilot users.

  13. Omega-3 (ω-3) and social skills interventions for reactive aggression and childhood externalizing behavior problems: a randomized, stratified, double-blind, placebo-controlled, factorial trial.

    PubMed

    Raine, Adrian; Ang, Rebecca P; Choy, Olivia; Hibbeln, Joseph R; Ho, Ringo M-H; Lim, Choon Guan; Lim-Ashworth, Nikki S J; Ling, Shichun; Liu, Jean C J; Ooi, Yoon Phaik; Tan, Yi Ren; Fung, Daniel S S

    2018-05-10

    While studies suggest that nutritional supplementation may reduce aggressive behavior in children, few have examined their effects on specific forms of aggression. This study tests the primary hypothesis that omega-3 (ω-3), both alone and in conjunction with social skills training, will have particular post-treatment efficacy for reducing childhood reactive aggression relative to baseline. In this randomized, double-blind, stratified, placebo-controlled, factorial trial, a clinical sample of 282 children with externalizing behavior aged 7-16 years was randomized into ω-3 only, social skills only, ω-3 + social skills, and placebo control groups. Treatment duration was 6 months. The primary outcome measure was reactive aggression collected at 0, 3, 6, 9, and 12 months, with antisocial behavior as a secondary outcome. Children in the ω-3-only group showed a short-term reduction (at 3 and 6 months) in self-report reactive aggression, and also a short-term reduction in overall antisocial behavior. Sensitivity analyses and a robustness check replicated significant interaction effects. Effect sizes (d) were small, ranging from 0.17 to 0.31. Findings provide some initial support for the efficacy of ω-3 in reducing reactive aggression over and above standard care (medication and parent training), but yield only preliminary and limited support for the efficacy of ω-3 in reducing overall externalizing behavior in children. Future studies could test further whether ω-3 shows promise in reducing more reactive, impulsive forms of aggression.

  14. Factors affecting failure to quit smoking after exposure to pictorial cigarette pack warnings among employees in Thailand.

    PubMed

    Sujirarat, Dusit; Silpasuwan, Pimpan; Viwatwongkasem, Chukiat; Sirichothiratana, Nithat

    2011-07-01

    This study was carried out to determine whether health warning pictures(HWP) affect smoking cessation using a structured equation model for intending-to-quit smokers in work places. Data from a 1-year longitudinal followup of attempt-to-quit employees was obtained to determine if pack warnings affect tobacco cessation rates. Stratified simple random sampling, and Structured Equation Modeling (SEM) were employed. Approximately 20% of intending-to-quit smokers were successful. The integrated model, combining internal, interpersonal factors and health warning pictures as external factors, fit the fail to quit pattern of the model. Having a smoking father was the most significant proximate indicator linked with failure to quit. Although HWL pictures were an external factor in the decision to stop smoking, the direct and indirect causes of failure to quit smoking were the influence of the family members. Fathers contributed to the success or failure of smoking cessation in their children by having an influence on the decision making process. Future HWP should include information about factors that stimulate smokers to quit successfully. The role model of a father on quitting is also important.

  15. 75 FR 56601 - Privacy Act of 1974: New System of Records

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-16

    ...The Patient Protection and Affordable Care Act (the Affordable Care Act), Public Law 111-148, was enacted on March 23, 2010; the Health Care and Education Reconciliation Act (the Reconciliation Act), Public Law 111-152, was enacted on March 30, 2010. The Affordable Care Act and implementing regulations (codified in HHS interim final rules (IFR) at 45 CFR Part 147) require that non-grandfathered health insurance plans and issuers offering group and individual coverage have effective internal claims and appeals and external review processes. The effective date for these requirements is plan or policy years beginning on or after September 23, 2010. Regarding external review, the statute requires that health plans and issuers must comply with either a state external review process or a process meeting standards issued by the Secretary of Health and Human Services (HHS) that is ``similar to'' a state process meeting requirements in section 2719 (a ``federal external review process''). The IFR includes a transition period prior to July 1, 2011, during which time HHS will work with states to assist in making any necessary changes so that the state process will meet the minimum consumer protections identified in 45 CFR 147.136 that must be met in order for the state process to apply. During this interim period, health insurance issuers in states with external review laws in effect prior to September 23, 2010 will follow that state's external review law to the extent applicable. In states that have not passed an external review law that is in effect on September 23, 2010, a health insurance issuer must follow an interim federal external review process that will be administered by the Office of Personnel Management (OPM). The system of records will be created as OPM assists HHS by providing external reviews of adverse benefit determinations and final internal adverse benefit determinations as requested by eligible claimants and their authorized representatives (``claimants''). The system of records will include any data relevant to these external reviews, and OPM proposes to add this new system of records to its inventory of records systems subject to the Privacy Act of 1974 (5 U.S.C. 552a), as amended. This action is necessary to meet the requirements of the Privacy Act to publish in the Federal Register notice of the existence and character of records maintained by the agency (5 U.S.C. 552a(e)(4)).

  16. NASA GSFC Mechanical Engineering Latest Inputs for Verification Standards (GEVS) Updates

    NASA Technical Reports Server (NTRS)

    Kaufman, Daniel

    2003-01-01

    This viewgraph presentation provides information on quality control standards in mechanical engineering. The presentation addresses safety, structural loads, nonmetallic composite structural elements, bonded structural joints, externally induced shock, random vibration, acoustic tests, and mechanical function.

  17. 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)

  18. External fixation versus open reduction with locked volar plating for geriatric distal radius fractures.

    PubMed

    Lee, Daniel J; Elfar, John C

    2014-09-01

    The optimal management of displaced dorsal radius fractures (DRFs) in older patients remains an issue of debate. Bridging external fixation is a well-accepted treatment modality for severely comminuted DRFs, while open reduction and internal fixation with locked volar plating has emerged as a promising alternative in recent years. The current body of randomized trials supports the trend toward locked volar plating, as it allows for quicker improvement in subjective and functional outcomes. There is no clear evidence to suggest that one technique carries significantly less complications than the other. Locked volar plating should be considered in patients for whom an accelerated functional recovery would be advantageous. Otherwise, both external fixation and locked volar plating provide good long-term clinical outcomes.

  19. Incentive-Elicited Mesolimbic Activation and Externalizing Symptomatology in Adolescents

    ERIC Educational Resources Information Center

    Bjork, James M.; Chen, Gang; Smith, Ashley R.; Hommer, Daniel W.

    2010-01-01

    Background: Opponent-process theories of externalizing disorders (ExD) attribute them to some combination of overactive reward processing systems and/or underactive behavior inhibition systems. Reward processing has been indexed by recruitment of incentive-motivational neurocircuitry of the ventral striatum (VS), including nucleus accumbens…

  20. Effective Recruitment of Schools for Randomized Clinical Trials: Role of School Nurses.

    PubMed

    Petosa, R L; Smith, L

    2017-01-01

    In school settings, nurses lead efforts to improve the student health and well-being to support academic success. Nurses are guided by evidenced-based practice and data to inform care decisions. The randomized controlled trial (RCT) is considered the gold standard of scientific rigor for clinical trials. RCTs are critical to the development of evidence-based health promotion programs in schools. The purpose of this article is to present practical solutions to implementing principles of randomization to RCT trials conducted in school settings. Randomization is a powerful sampling method used to build internal and external validity. The school's daily organization and educational mission provide several barriers to randomization. Based on the authors' experience in conducting school-based RCTs, they offer a host of practical solutions to working with schools to successfully implement randomization procedures. Nurses play a critical role in implementing RCTs in schools to promote rigorous science in support of evidence-based practice.

  1. Evaluation and Comparison of the Processing Methods of Airborne Gravimetry Concerning the Errors Effects on Downward Continuation Results: Case Studies in Louisiana (USA) and the Tibetan Plateau (China).

    PubMed

    Zhao, Qilong; Strykowski, Gabriel; Li, Jiancheng; Pan, Xiong; Xu, Xinyu

    2017-05-25

    Gravity data gaps in mountainous areas are nowadays often filled in with the data from airborne gravity surveys. Because of the errors caused by the airborne gravimeter sensors, and because of rough flight conditions, such errors cannot be completely eliminated. The precision of the gravity disturbances generated by the airborne gravimetry is around 3-5 mgal. A major obstacle in using airborne gravimetry are the errors caused by the downward continuation. In order to improve the results the external high-accuracy gravity information e.g., from the surface data can be used for high frequency correction, while satellite information can be applying for low frequency correction. Surface data may be used to reduce the systematic errors, while regularization methods can reduce the random errors in downward continuation. Airborne gravity surveys are sometimes conducted in mountainous areas and the most extreme area of the world for this type of survey is the Tibetan Plateau. Since there are no high-accuracy surface gravity data available for this area, the above error minimization method involving the external gravity data cannot be used. We propose a semi-parametric downward continuation method in combination with regularization to suppress the systematic error effect and the random error effect in the Tibetan Plateau; i.e., without the use of the external high-accuracy gravity data. We use a Louisiana airborne gravity dataset from the USA National Oceanic and Atmospheric Administration (NOAA) to demonstrate that the new method works effectively. Furthermore, and for the Tibetan Plateau we show that the numerical experiment is also successfully conducted using the synthetic Earth Gravitational Model 2008 (EGM08)-derived gravity data contaminated with the synthetic errors. The estimated systematic errors generated by the method are close to the simulated values. In addition, we study the relationship between the downward continuation altitudes and the error effect. The analysis results show that the proposed semi-parametric method combined with regularization is efficient to address such modelling problems.

  2. Evaluation and Comparison of the Processing Methods of Airborne Gravimetry Concerning the Errors Effects on Downward Continuation Results: Case Studies in Louisiana (USA) and the Tibetan Plateau (China)

    PubMed Central

    Zhao, Qilong; Strykowski, Gabriel; Li, Jiancheng; Pan, Xiong; Xu, Xinyu

    2017-01-01

    Gravity data gaps in mountainous areas are nowadays often filled in with the data from airborne gravity surveys. Because of the errors caused by the airborne gravimeter sensors, and because of rough flight conditions, such errors cannot be completely eliminated. The precision of the gravity disturbances generated by the airborne gravimetry is around 3–5 mgal. A major obstacle in using airborne gravimetry are the errors caused by the downward continuation. In order to improve the results the external high-accuracy gravity information e.g., from the surface data can be used for high frequency correction, while satellite information can be applying for low frequency correction. Surface data may be used to reduce the systematic errors, while regularization methods can reduce the random errors in downward continuation. Airborne gravity surveys are sometimes conducted in mountainous areas and the most extreme area of the world for this type of survey is the Tibetan Plateau. Since there are no high-accuracy surface gravity data available for this area, the above error minimization method involving the external gravity data cannot be used. We propose a semi-parametric downward continuation method in combination with regularization to suppress the systematic error effect and the random error effect in the Tibetan Plateau; i.e., without the use of the external high-accuracy gravity data. We use a Louisiana airborne gravity dataset from the USA National Oceanic and Atmospheric Administration (NOAA) to demonstrate that the new method works effectively. Furthermore, and for the Tibetan Plateau we show that the numerical experiment is also successfully conducted using the synthetic Earth Gravitational Model 2008 (EGM08)-derived gravity data contaminated with the synthetic errors. The estimated systematic errors generated by the method are close to the simulated values. In addition, we study the relationship between the downward continuation altitudes and the error effect. The analysis results show that the proposed semi-parametric method combined with regularization is efficient to address such modelling problems. PMID:28587086

  3. Evaluation and Comparison of the Processing Methods of Airborne Gravimetry Concerning the Errors Effects on Downward Continuation Results: Case Studies in Louisiana (USA) and the Tibetan Plateau (China)

    NASA Astrophysics Data System (ADS)

    Zhao, Q.

    2017-12-01

    Gravity data gaps in mountainous areas are nowadays often filled in with the data from airborne gravity surveys. Because of the errors caused by the airborne gravimeter sensors, and because of rough flight conditions, such errors cannot be completely eliminated. The precision of the gravity disturbances generated by the airborne gravimetry is around 3-5 mgal. A major obstacle in using airborne gravimetry are the errors caused by the downward continuation. In order to improve the results the external high-accuracy gravity information e.g., from the surface data can be used for high frequency correction, while satellite information can be applying for low frequency correction. Surface data may be used to reduce the systematic errors, while regularization methods can reduce the random errors in downward continuation. Airborne gravity surveys are sometimes conducted in mountainous areas and the most extreme area of the world for this type of survey is the Tibetan Plateau. Since there are no high-accuracy surface gravity data available for this area, the above error minimization method involving the external gravity data cannot be used. We propose a semi-parametric downward continuation method in combination with regularization to suppress the systematic error effect and the random error effect in the Tibetan Plateau; i.e., without the use of the external high-accuracy gravity data. We use a Louisiana airborne gravity dataset from the USA National Oceanic and Atmospheric Administration (NOAA) to demonstrate that the new method works effectively. Furthermore, and for the Tibetan Plateau we show that the numerical experiment is also successfully conducted using the synthetic Earth Gravitational Model 2008 (EGM08)-derived gravity data contaminated with the synthetic errors. The estimated systematic errors generated by the method are close to the simulated values. In addition, we study the relationship between the downward continuation altitudes and the error effect. The analysis results show that the proposed semi-parametric method combined with regularization is efficient to address such modelling problems.

  4. External Contamination Control of Attached Payloads on the International Space Station

    NASA Technical Reports Server (NTRS)

    Soares, Carlos E.; Mikatarian, Ronald R.; Olsen, Randy L.; Huang, Alvin Y.; Steagall, Courtney A.; Schmidl, William D.; Wright, Bruce D.; Koontz, Steven

    2012-01-01

    The International Space Station (ISS) is an on-orbit platform for science utilization in low Earth orbit with multiple sites for external payloads with exposure to the natural and induced environments. Contamination is one of the induced environments that can impact performance, mission success and science utilization on the vehicle. This paper describes the external contamination control requirements and integration process for externally mounted payloads on the ISS. The external contamination control requirements are summarized and a description of the integration and verification process is detailed to guide payload developers in the certification process of attached payloads on the vehicle. A description of the required data certification deliverables covers the characterization of contamination sources. Such characterization includes identification, usage and operational data for each class of contamination source. Classes of external contamination sources covered are vacuum exposed materials, sources of leakage, vacuum venting and thrusters. ISS system level analyses are conducted by the ISS Space Environments Team to certify compliance with external contamination control requirements. This paper also addresses the ISS induced contamination environment at attached payload sites, both at the requirements level as well as measurements made on ISS.

  5. Best strategies to implement clinical pathways in an emergency department setting: study protocol for a cluster randomized controlled trial

    PubMed Central

    2013-01-01

    Background The clinical pathway is a tool that operationalizes best evidence recommendations and clinical practice guidelines in an accessible format for ‘point of care’ management by multidisciplinary health teams in hospital settings. While high-quality, expert-developed clinical pathways have many potential benefits, their impact has been limited by variable implementation strategies and suboptimal research designs. Best strategies for implementing pathways into hospital settings remain unknown. This study will seek to develop and comprehensively evaluate best strategies for effective local implementation of externally developed expert clinical pathways. Design/methods We will develop a theory-based and knowledge user-informed intervention strategy to implement two pediatric clinical pathways: asthma and gastroenteritis. Using a balanced incomplete block design, we will randomize 16 community emergency departments to receive the intervention for one clinical pathway and serve as control for the alternate clinical pathway, thus conducting two cluster randomized controlled trials to evaluate this implementation intervention. A minimization procedure will be used to randomize sites. Intervention sites will receive a tailored strategy to support full clinical pathway implementation. We will evaluate implementation strategy effectiveness through measurement of relevant process and clinical outcomes. The primary process outcome will be the presence of an appropriately completed clinical pathway on the chart for relevant patients. Primary clinical outcomes for each clinical pathway include the following: Asthma—the proportion of asthmatic patients treated appropriately with corticosteroids in the emergency department and at discharge; and Gastroenteritis—the proportion of relevant patients appropriately treated with oral rehydration therapy. Data sources include chart audits, administrative databases, environmental scans, and qualitative interviews. We will also conduct an overall process evaluation to assess the implementation strategy and an economic analysis to evaluate implementation costs and benefits. Discussion This study will contribute to the body of evidence supporting effective strategies for clinical pathway implementation, and ultimately reducing the research to practice gaps by operationalizing best evidence care recommendations through effective use of clinical pathways. Trial registration ClinicalTrials.gov: NCT01815710 PMID:23692634

  6. Scattering Properties of Heterogeneous Mineral Particles with Absorbing Inclusions

    NASA Technical Reports Server (NTRS)

    Dlugach, Janna M.; Mishchenko, Michael I.

    2015-01-01

    We analyze the results of numerically exact computer modeling of scattering and absorption properties of randomly oriented poly-disperse heterogeneous particles obtained by placing microscopic absorbing grains randomly on the surfaces of much larger spherical mineral hosts or by imbedding them randomly inside the hosts. These computations are paralleled by those for heterogeneous particles obtained by fully encapsulating fractal-like absorbing clusters in the mineral hosts. All computations are performed using the superposition T-matrix method. In the case of randomly distributed inclusions, the results are compared with the outcome of Lorenz-Mie computations for an external mixture of the mineral hosts and absorbing grains. We conclude that internal aggregation can affect strongly both the integral radiometric and differential scattering characteristics of the heterogeneous particle mixtures.

  7. Does Focus of Attention Improve Snatch Lift Kinematics?

    PubMed

    Schutts, Kyle S; Wu, Will F W; Vidal, Anthony D; Hiegel, Jamie; Becker, James

    2017-10-01

    Recent motor control literature has demonstrated that using verbal instructions to direct a performer's attention externally (i.e., toward the movement outcome) enhances motor skill performance. The purpose of this study was to investigate how an athlete's focus of attention impacts kinematic performance of the snatch. Using a counterbalanced within-participant design, 12 competitively trained athletes (8 male and 4 female athletes) performed 2 instructional blocks of 3 snatch repetitions at 80% of their most recent training 1 repetition maximum. Blocks of internal and external instructions were given to the athlete in a random fashion. Results showed that, when focusing internally, athletes significantly (p ≤ 0.05) increased elbow velocity relative to focusing externally, whereas the external instructions significantly increased horizontal barbell velocity, relative to internal instructions. Additionally, an internal focus resulted in significantly larger barbell-cervical-hip angles at maximum height of the barbell compared with an external focus, indicating that the athletes squatted under the barbell too soon. This information adds to the literature suggesting small changes in coaching instructions can impact performance significantly. It is recommended that coaches use instructions that direct an athlete's attention externally, toward the movement outcome, rather than the action itself.

  8. Proceedings: National conference on environmental externalities

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1990-12-31

    This report is the proceedings of the National Conference on Environmental Externalities. A environmental externality is the environmental impact of a process or a plant that society must endure. It is a social cost and is paid, but not by the company who produced it or the company`s customers who endure it. The main purpose of this report is to gather the many designs and ideas of how and why to internalize the externalities into the pricing systems of the public utility commissions, especially that of the electric utilities. Economic and sociological aspects of the internalization of these externalities aremore » given in these proceedings. Individual papers are processed separately for databases. (MB)« less

  9. Processing device with self-scrubbing logic

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wojahn, Christopher K.

    An apparatus includes a processing unit including a configuration memory and self-scrubber logic coupled to read the configuration memory to detect compromised data stored in the configuration memory. The apparatus also includes a watchdog unit external to the processing unit and coupled to the self-scrubber logic to detect a failure in the self-scrubber logic. The watchdog unit is coupled to the processing unit to selectively reset the processing unit in response to detecting the failure in the self-scrubber logic. The apparatus also includes an external memory external to the processing unit and coupled to send configuration data to the configurationmore » memory in response to a data feed signal outputted by the self-scrubber logic.« less

  10. Neurobiologically realistic determinants of self-organized criticality in networks of spiking neurons.

    PubMed

    Rubinov, Mikail; Sporns, Olaf; Thivierge, Jean-Philippe; Breakspear, Michael

    2011-06-01

    Self-organized criticality refers to the spontaneous emergence of self-similar dynamics in complex systems poised between order and randomness. The presence of self-organized critical dynamics in the brain is theoretically appealing and is supported by recent neurophysiological studies. Despite this, the neurobiological determinants of these dynamics have not been previously sought. Here, we systematically examined the influence of such determinants in hierarchically modular networks of leaky integrate-and-fire neurons with spike-timing-dependent synaptic plasticity and axonal conduction delays. We characterized emergent dynamics in our networks by distributions of active neuronal ensemble modules (neuronal avalanches) and rigorously assessed these distributions for power-law scaling. We found that spike-timing-dependent synaptic plasticity enabled a rapid phase transition from random subcritical dynamics to ordered supercritical dynamics. Importantly, modular connectivity and low wiring cost broadened this transition, and enabled a regime indicative of self-organized criticality. The regime only occurred when modular connectivity, low wiring cost and synaptic plasticity were simultaneously present, and the regime was most evident when between-module connection density scaled as a power-law. The regime was robust to variations in other neurobiologically relevant parameters and favored systems with low external drive and strong internal interactions. Increases in system size and connectivity facilitated internal interactions, permitting reductions in external drive and facilitating convergence of postsynaptic-response magnitude and synaptic-plasticity learning rate parameter values towards neurobiologically realistic levels. We hence infer a novel association between self-organized critical neuronal dynamics and several neurobiologically realistic features of structural connectivity. The central role of these features in our model may reflect their importance for neuronal information processing.

  11. Whole of Systems Trial of Prevention Strategies for Childhood Obesity: WHO STOPS Childhood Obesity.

    PubMed

    Allender, Steven; Millar, Lynne; Hovmand, Peter; Bell, Colin; Moodie, Marj; Carter, Rob; Swinburn, Boyd; Strugnell, Claudia; Lowe, Janette; de la Haye, Kayla; Orellana, Liliana; Morgan, Sue

    2016-11-16

    Background : Community-based initiatives show promise for preventing childhood obesity. They are characterized by community leaders and members working together to address complex local drivers of energy balance. Objectives : To present a protocol for a stepped wedge cluster randomized trial in ten communities in the Great South Coast Region of Victoria, Australia to test whether it is possible to: (1) strengthen community action for childhood obesity prevention, and (2) measure the impact of increased action on risk factors for childhood obesity. Methods: The WHO STOPS intervention involves a facilitated community engagement process that: creates an agreed systems map of childhood obesity causes for a community; identifies intervention opportunities through leveraging the dynamic aspects of the system; and, converts these understandings into community-built, systems-oriented action plans. Ten communities will be randomized (1:1) to intervention or control in year one and all communities will be included by year three. The primary outcome is childhood obesity prevalence among grade two (ages 7-8 y), grade four (9-10 y) and grade six (11-12 y) students measured using our established community-led monitoring system (69% school and 93% student participation rate in government and independent schools). An additional group of 13 external communities from other regions of Victoria with no specific interventions will provide an external comparison. These communities will also allow us to assess diffusion of the intervention to control communities during the first three years of the trial. Conclusion : This trial will test effectiveness, over a five-year period, of community-owned, -supported and -led strategies designed to address complex and dynamic causes of childhood obesity.

  12. Whole of Systems Trial of Prevention Strategies for Childhood Obesity: WHO STOPS Childhood Obesity

    PubMed Central

    Allender, Steven; Millar, Lynne; Hovmand, Peter; Bell, Colin; Moodie, Marj; Carter, Rob; Swinburn, Boyd; Strugnell, Claudia; Lowe, Janette; de la Haye, Kayla; Orellana, Liliana; Morgan, Sue

    2016-01-01

    Background: Community-based initiatives show promise for preventing childhood obesity. They are characterized by community leaders and members working together to address complex local drivers of energy balance. Objectives: To present a protocol for a stepped wedge cluster randomized trial in ten communities in the Great South Coast Region of Victoria, Australia to test whether it is possible to: (1) strengthen community action for childhood obesity prevention, and (2) measure the impact of increased action on risk factors for childhood obesity. Methods: The WHO STOPS intervention involves a facilitated community engagement process that: creates an agreed systems map of childhood obesity causes for a community; identifies intervention opportunities through leveraging the dynamic aspects of the system; and, converts these understandings into community-built, systems-oriented action plans. Ten communities will be randomized (1:1) to intervention or control in year one and all communities will be included by year three. The primary outcome is childhood obesity prevalence among grade two (ages 7–8 y), grade four (9–10 y) and grade six (11–12 y) students measured using our established community-led monitoring system (69% school and 93% student participation rate in government and independent schools). An additional group of 13 external communities from other regions of Victoria with no specific interventions will provide an external comparison. These communities will also allow us to assess diffusion of the intervention to control communities during the first three years of the trial. Conclusion: This trial will test effectiveness, over a five-year period, of community-owned, -supported and -led strategies designed to address complex and dynamic causes of childhood obesity. PMID:27854354

  13. Externalization of the Health Care System's Educational Programs.

    ERIC Educational Resources Information Center

    Seisser, Mary A.; Epstein, Alice L.

    1999-01-01

    Health care organizations with successful internal education programs can expand their offerings through a formal externalization process. The process involves needs assessment, environmental scanning, identification of internal successes, and selection of appropriate topics. (SK)

  14. A Monte Carlo analysis of breast screening randomized trials.

    PubMed

    Zamora, Luis I; Forastero, Cristina; Guirado, Damián; Lallena, Antonio M

    2016-12-01

    To analyze breast screening randomized trials with a Monte Carlo simulation tool. A simulation tool previously developed to simulate breast screening programmes was adapted for that purpose. The history of women participating in the trials was simulated, including a model for survival after local treatment of invasive cancers. Distributions of time gained due to screening detection against symptomatic detection and the overall screening sensitivity were used as inputs. Several randomized controlled trials were simulated. Except for the age range of women involved, all simulations used the same population characteristics and this permitted to analyze their external validity. The relative risks obtained were compared to those quoted for the trials, whose internal validity was addressed by further investigating the reasons of the disagreements observed. The Monte Carlo simulations produce results that are in good agreement with most of the randomized trials analyzed, thus indicating their methodological quality and external validity. A reduction of the breast cancer mortality around 20% appears to be a reasonable value according to the results of the trials that are methodologically correct. Discrepancies observed with Canada I and II trials may be attributed to a low mammography quality and some methodological problems. Kopparberg trial appears to show a low methodological quality. Monte Carlo simulations are a powerful tool to investigate breast screening controlled randomized trials, helping to establish those whose results are reliable enough to be extrapolated to other populations and to design the trial strategies and, eventually, adapting them during their development. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  15. Describing and Predicting Developmental Profiles of Externalizing Problems from Childhood to Adulthood

    PubMed Central

    Petersen, Isaac T.; Bates, John E.; Dodge, Kenneth A.; Lansford, Jennifer E.; Pettit, Gregory S.

    2014-01-01

    This longitudinal study considers externalizing behavior problems from ages 5 to 27 (N = 585). Externalizing problem ratings by mothers, fathers, teachers, peers, and self-report were modeled with growth curves. Risk and protective factors across many different domains and time frames were included as predictors of the trajectories. A major contribution of the study is in demonstrating how heterotypic continuity and changing measures can be handled in modeling changes in externalizing behavior over long developmental periods. On average, externalizing problems decreased from early childhood to preadolescence, increased during adolescence, and decreased from late adolescence to adulthood. There was strong nonlinear continuity in externalizing problems over time. Family process, peer process, stress, and individual characteristics predicted externalizing problems beyond the strong continuity of externalizing problems. The model accounted for 70% of the variability in the development of externalizing problems. The model’s predicted values showed moderate sensitivity and specificity in prediction of arrests, illegal drug use, and drunk driving. Overall, the study showed that by using changing, developmentally-relevant measures and simultaneously taking into account numerous characteristics of children and their living situations, research can model lengthy spans of development and improve predictions of the development of later, severe externalizing problems. PMID:25166430

  16. Time series analysis for minority game simulations of financial markets

    NASA Astrophysics Data System (ADS)

    Ferreira, Fernando F.; Francisco, Gerson; Machado, Birajara S.; Muruganandam, Paulsamy

    2003-04-01

    The minority game (MG) model introduced recently provides promising insights into the understanding of the evolution of prices, indices and rates in the financial markets. In this paper we perform a time series analysis of the model employing tools from statistics, dynamical systems theory and stochastic processes. Using benchmark systems and a financial index for comparison, several conclusions are obtained about the generating mechanism for this kind of evolution. The motion is deterministic, driven by occasional random external perturbation. When the interval between two successive perturbations is sufficiently large, one can find low dimensional chaos in this regime. However, the full motion of the MG model is found to be similar to that of the first differences of the SP500 index: stochastic, nonlinear and (unit root) stationary.

  17. Automation of POST Cases via External Optimizer and "Artificial p2" Calculation

    NASA Technical Reports Server (NTRS)

    Dees, Patrick D.; Zwack, Mathew R.; Michelson, Diane K.

    2017-01-01

    During conceptual design speed and accuracy are often at odds. Specifically in the realm of launch vehicles, optimizing the ascent trajectory requires a larger pool of analytical power and expertise. Experienced analysts working on familiar vehicles can produce optimal trajectories in a short time frame, however whenever either "experienced" or "familiar " is not applicable the optimization process can become quite lengthy. In order to construct a vehicle agnostic method an established global optimization algorithm is needed. In this work the authors develop an "artificial" error term to map arbitrary control vectors to non-zero error by which a global method can operate. Two global methods are compared alongside Design of Experiments and random sampling and are shown to produce comparable results to analysis done by a human expert.

  18. Global industrial impact coefficient based on random walk process and inter-country input-output table

    NASA Astrophysics Data System (ADS)

    Xing, Lizhi; Dong, Xianlei; Guan, Jun

    2017-04-01

    Input-output table is very comprehensive and detailed in describing the national economic system with lots of economic relationships, which contains supply and demand information among industrial sectors. The complex network, a theory and method for measuring the structure of complex system, can describe the structural characteristics of the internal structure of the research object by measuring the structural indicators of the social and economic system, revealing the complex relationship between the inner hierarchy and the external economic function. This paper builds up GIVCN-WIOT models based on World Input-Output Database in order to depict the topological structure of Global Value Chain (GVC), and assumes the competitive advantage of nations is equal to the overall performance of its domestic sectors' impact on the GVC. Under the perspective of econophysics, Global Industrial Impact Coefficient (GIIC) is proposed to measure the national competitiveness in gaining information superiority and intermediate interests. Analysis of GIVCN-WIOT models yields several insights including the following: (1) sectors with higher Random Walk Centrality contribute more to transmitting value streams within the global economic system; (2) Half-Value Ratio can be used to measure robustness of open-economy macroeconomics in the process of globalization; (3) the positive correlation between GIIC and GDP indicates that one country's global industrial impact could reveal its international competitive advantage.

  19. Does the Incredible Years reduce child externalizing problems through improved parenting? The role of child negative affectivity and serotonin transporter linked polymorphic region (5-HTTLPR) genotype.

    PubMed

    Weeland, Joyce; Chhangur, Rabia R; Jaffee, Sara R; Van Der Giessen, Danielle; Matthys, Walter; Orobio De Castro, Bram; Overbeek, Geertjan

    2018-02-01

    In a randomized controlled trial, the Observational Randomized Controlled Trial of Childhood Differential Susceptibility (ORCHIDS study), we tested whether observed parental affect and observed and reported parenting behavior are mechanisms of change underlying the effects of the behavioral parent training program the Incredible Years (IY). Furthermore, we tested whether some children are more susceptible to these change mechanisms because of their temperamental negative affectivity and/or serotonin transporter linked polymorphic region (5-HTTLPR) genotype. Participants were 387 Dutch children between 4 and 8 years of age (M age = 6.31, SD = 1.33; 55.3% boys) and their parents. Results showed that although IY was successful in improving parenting behavior and increasing parental positive affect, these effects did not explain the significant decreases in child externalizing problems. We therefore found no evidence for changes in parenting behavior or parental affect being the putative mechanisms of IY effectiveness. Furthermore, intervention effects on child externalizing behavior were not moderated by child negative affectivity or 5-HTTLPR genotype. However, child 5-HTTLPR genotype did moderate intervention effects on negative parenting behavior. This suggests that in research on behavioral parent training programs, "what works for which parents" might also be an important question.

  20. Effect of virtual reality versus conventional physiotherapy on upper extremity function in children with obstetric brachial plexus injury

    PubMed Central

    El-Shamy, Shamekh; Alsharif, Rabab

    2017-01-01

    Objectives: The objective was to evaluate the effects of virtual reality versus conventional physiotherapy on upper extremity function in children with obstetric brachial plexus injury. Methods: Forty children with Erb’s palsy were selected for this randomized controlled study. They were assigned randomly to either group A (conventional physiotherapy program) or group B (virtual reality program using Armeo® spring for 45 min three times/week for 12 successive weeks). Mallet system scores for shoulder function and shoulder abduction, and external rotation range of motion (ROM) were obtained; shoulder abductor, and external rotators isometric strength were evaluated pre-and post-treatment using Mallet scoring system, standard universal goniometer, and handheld dynamometer. Results: The results of this study indicate that the children in both groups showed improvement in shoulder functions post-treatment with greater improvements in group B. The abduction muscle strength after treatment was 8.53 and 11.3 Nm for group A and group B, respectively. The external rotation muscle strength after treatment was 5.88 and 7.45 Nm for group A and group B, respectively. Conclusions: The virtual reality program is a significantly more effective than conventional physiotherapy program in improving the upper extremity functions in children with obstetric brachial plexus injury. PMID:29199193

  1. Magnetic field effect on growth, arsenic uptake, and total amylolytic activity on mesquite (Prosopis juliflora x P. velutina) seeds

    NASA Astrophysics Data System (ADS)

    Flores-Tavizón, Edith; Mokgalaka-Matlala, Ntebogeng S.; Elizalde Galindo, José T.; Castillo-Michelle, Hiram; Peralta-Videa, Jose R.; Gardea-Torresdey, Jorge L.

    2012-04-01

    Magnetic field is closely related to the cell metabolism of plants [N. A. Belyavskaya, Adv. Space Res. 34, 1566 (2004)]. In order to see the effect of magnetic field on the plant growth, arsenic uptake, and total amylolytic activity of mesquite (Prosopis juliflora x P. velutina) seeds, ten sets of 80 seeds were selected to be oriented with the long axis parallel or randomly oriented to an external magnetic field. The external magnetic field magnitude was 1 T, and the exposition time t = 30 min. Then, the seeds were stored for three days in a plastic bag and then sown on paper towels in a modified Hoagland's nutrient solution. After three days of germination in the dark and three days in light, seedlings were grown hydroponically in modified Hoagland's nutrient solution (high PO42-) containing 0, 10, or 20 ppm of arsenic as As (III) and (V). The results show that the germination ratios, growth, elongation, arsenic uptake, and total amylolytic activity of the long axis oriented mesquite seeds were much higher than those of the randomly oriented seeds. Also, these two sets of seeds showed higher properties than the ones that were not exposed to external magnetic field.

  2. An Exploratory Study: Assessment of Modeled Dioxin Exposure in Ceramic Art Studios (External Review Draft)

    EPA Science Inventory

    EPA has released an external review draft entitled, An Exploratory Study: Assessment of Modeled Dioxin Exposure in Ceramic Art Studios(External Review Draft). The public comment period and the external peer-review workshop are separate processes that provide opportunities ...

  3. Pervasive randomness in physics: an introduction to its modelling and spectral characterisation

    NASA Astrophysics Data System (ADS)

    Howard, Roy

    2017-10-01

    An introduction to the modelling and spectral characterisation of random phenomena is detailed at a level consistent with a first exposure to the subject at an undergraduate level. A signal framework for defining a random process is provided and this underpins an introduction to common random processes including the Poisson point process, the random walk, the random telegraph signal, shot noise, information signalling random processes, jittered pulse trains, birth-death random processes and Markov chains. An introduction to the spectral characterisation of signals and random processes, via either an energy spectral density or a power spectral density, is detailed. The important case of defining a white noise random process concludes the paper.

  4. Adding temporally localized noise can enhance the contribution of target knowledge on contrast detection.

    PubMed

    Silvestre, Daphné; Cavanagh, Patrick; Arleo, Angelo; Allard, Rémy

    2017-02-01

    External noise paradigms are widely used to characterize sensitivity by comparing the effect of a variable on contrast threshold when it is limited by internal versus external noise. A basic assumption of external noise paradigms is that the processing properties are the same in low and high noise. However, recent studies (e.g., Allard & Cavanagh, 2011; Allard & Faubert, 2014b) suggest that this assumption could be violated when using spatiotemporally localized noise (i.e., appearing simultaneously and at the same location as the target) but not when using spatiotemporally extended noise (i.e., continuously displayed, full-screen, dynamic noise). These previous findings may have been specific to the crowding and 0D noise paradigms that were used, so the purpose of the current study is to test if this violation of noise-invariant processing also occurs in a standard contrast detection task in white noise. The rationale of the current study is that local external noise triggers the use of recognition rather than detection and that a recognition process should be more affected by uncertainty about the shape of the target than one involving detection. To investigate the contribution of target knowledge on contrast detection, the effect of orientation uncertainty was evaluated for a contrast detection task in the absence of noise and in the presence of spatiotemporally localized or extended noise. A larger orientation uncertainty effect was observed with temporally localized noise than with temporally extended noise or with no external noise, indicating a change in the nature of the processing for temporally localized noise. We conclude that the use of temporally localized noise in external noise paradigms risks triggering a shift in process, invalidating the noise-invariant processing required for the paradigm. If, instead, temporally extended external noise is used to match the properties of internal noise, no such processing change occurs.

  5. A process for Decision-making after Pilot and feasibility Trials (ADePT): development following a feasibility study of a complex intervention for pelvic organ prolapse

    PubMed Central

    2013-01-01

    Background Current Medical Research Council (MRC) guidance on complex interventions advocates pilot trials and feasibility studies as part of a phased approach to the development, testing, and evaluation of healthcare interventions. In this paper we discuss the results of a recent feasibility study and pilot trial for a randomized controlled trial (RCT) of pelvic floor muscle training for prolapse (ClinicalTrials.gov: NCT01136889). The ways in which researchers decide to respond to the results of feasibility work may have significant repercussions for both the nature and degree of tension between internal and external validity in a definitive trial. Methods We used methodological issues to classify and analyze the problems that arose in the feasibility study. Four centers participated with the aim of randomizing 50 women. Women were eligible if they had prolapse of any type, of stage I to IV, and had a pessary successfully fitted. Postal questionnaires were administered at baseline, 6 months, and 7 months post-randomization. After identifying problems arising within the pilot study we then sought to locate potential solutions that might minimize the trade-off between a subsequent explanatory versus pragmatic trial. Results The feasibility study pointed to significant potential problems in relation to participant recruitment, features of the intervention, acceptability of the intervention to participants, and outcome measurement. Finding minimal evidence to support our decision-making regarding the transition from feasibility work to a trial, we developed a systematic process (A process for Decision-making after Pilot and feasibility Trials (ADePT)) which we subsequently used as a guide. The process sought to: 1) encourage the systematic identification and appraisal of problems and potential solutions; 2) improve the transparency of decision-making processes; and 3) reveal the tensions that exist between pragmatic and explanatory choices. Conclusions We have developed a process that may aid researchers in their attempt to identify the most appropriate solutions to problems identified within future pilot and feasibility RCTs. The process includes three key steps: a decision about the type of problem, the identification of all solutions (whether addressed within the intervention, trial design or clinical context), and a systematic appraisal of these solutions. PMID:24160371

  6. Discrete diffusion models to study the effects of Mg2+ concentration on the PhoPQ signal transduction system

    PubMed Central

    2010-01-01

    Background The challenge today is to develop a modeling and simulation paradigm that integrates structural, molecular and genetic data for a quantitative understanding of physiology and behavior of biological processes at multiple scales. This modeling method requires techniques that maintain a reasonable accuracy of the biological process and also reduces the computational overhead. This objective motivates the use of new methods that can transform the problem from energy and affinity based modeling to information theory based modeling. To achieve this, we transform all dynamics within the cell into a random event time, which is specified through an information domain measure like probability distribution. This allows us to use the “in silico” stochastic event based modeling approach to find the molecular dynamics of the system. Results In this paper, we present the discrete event simulation concept using the example of the signal transduction cascade triggered by extra-cellular Mg2+ concentration in the two component PhoPQ regulatory system of Salmonella Typhimurium. We also present a model to compute the information domain measure of the molecular transport process by estimating the statistical parameters of inter-arrival time between molecules/ions coming to a cell receptor as external signal. This model transforms the diffusion process into the information theory measure of stochastic event completion time to get the distribution of the Mg2+ departure events. Using these molecular transport models, we next study the in-silico effects of this external trigger on the PhoPQ system. Conclusions Our results illustrate the accuracy of the proposed diffusion models in explaining the molecular/ionic transport processes inside the cell. Also, the proposed simulation framework can incorporate the stochasticity in cellular environments to a certain degree of accuracy. We expect that this scalable simulation platform will be able to model more complex biological systems with reasonable accuracy to understand their temporal dynamics. PMID:21143785

  7. Discrete diffusion models to study the effects of Mg2+ concentration on the PhoPQ signal transduction system.

    PubMed

    Ghosh, Preetam; Ghosh, Samik; Basu, Kalyan; Das, Sajal K; Zhang, Chaoyang

    2010-12-01

    The challenge today is to develop a modeling and simulation paradigm that integrates structural, molecular and genetic data for a quantitative understanding of physiology and behavior of biological processes at multiple scales. This modeling method requires techniques that maintain a reasonable accuracy of the biological process and also reduces the computational overhead. This objective motivates the use of new methods that can transform the problem from energy and affinity based modeling to information theory based modeling. To achieve this, we transform all dynamics within the cell into a random event time, which is specified through an information domain measure like probability distribution. This allows us to use the "in silico" stochastic event based modeling approach to find the molecular dynamics of the system. In this paper, we present the discrete event simulation concept using the example of the signal transduction cascade triggered by extra-cellular Mg2+ concentration in the two component PhoPQ regulatory system of Salmonella Typhimurium. We also present a model to compute the information domain measure of the molecular transport process by estimating the statistical parameters of inter-arrival time between molecules/ions coming to a cell receptor as external signal. This model transforms the diffusion process into the information theory measure of stochastic event completion time to get the distribution of the Mg2+ departure events. Using these molecular transport models, we next study the in-silico effects of this external trigger on the PhoPQ system. Our results illustrate the accuracy of the proposed diffusion models in explaining the molecular/ionic transport processes inside the cell. Also, the proposed simulation framework can incorporate the stochasticity in cellular environments to a certain degree of accuracy. We expect that this scalable simulation platform will be able to model more complex biological systems with reasonable accuracy to understand their temporal dynamics.

  8. Personal resources and support when regaining the ability to work: an interview study with Exhaustion Disorder patients.

    PubMed

    Norlund, Sofia; Fjellman-Wiklund, Anncristine; Nordin, Maria; Stenlund, Therese; Ahlgren, Christina

    2013-06-01

    The aim of the study was to explore experiences and thoughts in the process of returning to work in employed patients with Exhaustion Disorder. Twelve patients with Exhaustion Disorder (burnout) who had been referred to a Stress Rehabilitation Clinic were interviewed. All patients were employed but a majority was on full or part-time sick leave. Grounded Theory was used as the qualitative method. A core category, regaining the ability to work, was developed. Alongside, two categories, internal resources and the external support system, were experienced as being important to the process. The internal resources were expressed through three key features (sub-categories), perceived validation, insights and adaptive coping abilities. The external support system was diverse and described by the sub-categories practical/structural and/or emotional support. Four external support actors were identified; the workplace, health care, the Social Insurance Agency, and the union. The supervisor was described as the most important external actor. Internal and external resources are intertwined in the process of regaining the ability to work. The internal resources and external support can directly increase the probability to regain the ability to work. Moreover, these resources can affect each other and thus indirectly have an effect on the process.

  9. Understanding the Stress Process of Chinese- and Korean-American Breast Cancer Survivors.

    PubMed

    Paek, Min-So; Lim, Jung-Won

    2016-10-01

    Guided by the stress process model (SPM), this study investigated the direct and indirect pathways of primary (negative self-image and life stress), secondary stressors (family communication strain) and family coping (external and internal) on mental health outcomes among Chinese- and Korean-American breast cancer survivors (BCS). A total of 156 Chinese- and Korean-American BCS were surveyed. Results showed primary and secondary stressors had a negative effect on better mental health outcomes. External coping was associated with better mental health. Family communication strain mediated the relationship between life stress and mental health outcomes. External coping mediated the relationship between family communication strain and mental health outcomes. Multi-group analysis revealed the stress process did not differ across ethnic groups. Findings suggest the SPM may be applicable to understand the stress process of Chinese- and Korean-American BCS and provide valuable insight into the role of family communication and external coping on mental health outcomes.

  10. Parent–Child Conflict and Early Childhood Adjustment in Two-Parent Low-Income Families: Parallel Developmental Processes

    PubMed Central

    Shaw, Daniel S.; Crossan, Jennifer L.; Dishion, Thomas J.; Wilson, Melvin N.

    2015-01-01

    Parent–child conflict is central to most intervention models focused on reducing child problem behavior, yet few longitudinal studies have examined these processes during early childhood. The current study investigates (1) growth in mother–child and father figure (FF)–child conflict, (2) associations between trajectories of mother–child and FF–child conflict and children’s adjustment; and (3) intervention effects in attenuating conflict. Participants are 195 ethnically diverse mother–FF–child triads drawn from a larger parenting intervention study for families with children at risk for developing conduct problems. Mother–child conflict decreased from ages 2 to 4, but decreases were unrelated to changes in children’s adjustment problems. In contrast, the slope of FF–child conflict was positively related to the slope of child externalizing behaviors. Random assignment to a family-centered parenting intervention predicted rate of decline in mother–child conflict. Findings are discussed with respect to developmental patterns of parent–child conflict in early childhood and implications for prevention. PMID:24610382

  11. Transition to turbulence under low-pressure turbine conditions.

    PubMed

    Simon, T W; Kaszeta, R W

    2001-05-01

    In this paper, the topic of laminar to turbulent flow transition, as applied to the design of gas turbines, is discussed. Transition comes about when a flow becomes sufficiently unstable that the orderly vorticity structure of the laminar layer becomes randomly oriented. Vorticity with a streamwise component leads to rapid growth of eddies of a wide range of sizes and eventually to turbulent flow. Under "natural" transition, infinitesimal disturbances of selected frequencies grow. "Bypass transition" is a term coined to describe a similar process, but one driven by strong external disturbances. Transition proceeds so rapidly that the processes associated with "natural" transition seem to be "bypassed." Because the flow environment in the turbine is disturbed by wakes from upstream airfoils, eddies from combustor flows, jets from film cooling, separation zones on upstream airfoils and steps in the duct walls, transition is of the bypass mode. In this paper, we discuss work that has been done to characterize and model bypass transition, as applied to the turbine environment.

  12. Wetting and Interfacial Reactivity of Zn-Coated Steel Products with Cu-Si, Cu-Sn and Al-Si Filler Metals for Laser Brazing Application

    NASA Astrophysics Data System (ADS)

    Koltsov, Alexey; Cretteur, Laurent

    2018-03-01

    The laser brazing process is successfully applied in automotive industry for joining of roofs and hatchbacks of vehicles. The bad wetting of the brazing alloy during the process can lead to the formation of random external porosities which are not allowed on visible parts. This paper describes the wettability and reactivity mechanisms at short contact time of Cu and Al matrix brazing alloys with different reactive elements (Si, Sn) on different steel products such as hot-dip galvanized steels, galvannealed steel and bare steel. Wetting experiments were carried out by the dispensed drop technique. The effects of alloying elements and brazing alloy matrix on interfacial reactivity are discussed. It was found that Cu matrix containing 3 wt.% Si is the most favorable for short time liquid/solid adhesion relatively to the other studied brazing alloy compositions. The brazing ability of different steel products is well correlated with the wettability and interfacial reactivity results.

  13. Vibration study of a vehicle suspension assembly with the finite element method

    NASA Astrophysics Data System (ADS)

    Cătălin Marinescu, Gabriel; Castravete, Ştefan-Cristian; Dumitru, Nicolae

    2017-10-01

    The main steps of the present work represent a methodology of analysing various vibration effects over suspension mechanical parts of a vehicle. A McPherson type suspension from an existing vehicle was created using CAD software. Using the CAD model as input, a finite element model of the suspension assembly was developed. Abaqus finite element analysis software was used to pre-process, solve, and post-process the results. Geometric nonlinearities are included in the model. Severe sources of nonlinearities such us friction and contact are also included in the model. The McPherson spring is modelled as linear spring. The analysis include several steps: preload, modal analysis, the reduction of the model to 200 generalized coordinates, a deterministic external excitation, a random excitation that comes from different types of roads. The vibration data used as an input for the simulation were previously obtained by experimental means. Mathematical expressions used for the simulation were also presented in the paper.

  14. Mass storage technology in networks

    NASA Astrophysics Data System (ADS)

    Ishii, Katsunori; Takeda, Toru; Itao, Kiyoshi; Kaneko, Reizo

    1990-08-01

    Trends and features of mass storage subsystems in network are surveyed and their key technologies spotlighted. Storage subsystems are becoming increasingly important in new network systems in which communications and data processing are systematically combined. These systems require a new class of high-performance mass-information storage in order to effectively utilize their processing power. The requirements of high transfer rates, high transactional rates and large storage capacities, coupled with high functionality, fault tolerance and flexibility in configuration, are major challenges in storage subsystems. Recent progress in optical disk technology has resulted in improved performance of on-line external memories to optical disk drives, which are competing with mid-range magnetic disks. Optical disks are more effective than magnetic disks in using low-traffic random-access file storing multimedia data that requires large capacity, such as in archive use and in information distribution use by ROM disks. Finally, it demonstrates image coded document file servers for local area network use that employ 130mm rewritable magneto-optical disk subsystems.

  15. Deepening our understanding of quality improvement in Europe (DUQuE): overview of a study of hospital quality management in seven countries

    PubMed Central

    Secanell, Mariona; Groene, Oliver; Arah, Onyebuchi A.; Lopez, Maria Andrée; Kutryba, Basia; Pfaff, Holger; Klazinga, Niek; Wagner, Cordula; Kristensen, Solvejg; Bartels, Paul Daniel; Garel, Pascal; Bruneau, Charles; Escoval, Ana; França, Margarida; Mora, Nuria; Suñol, Rosa; Klazinga, N; Kringos, DS; Lopez, MA; Secanell, M; Sunol, R; Vallejo, P; Bartels, P; Kristensen, S; Michel, P; Saillour-Glenisson, F; Vlcek, F; Car, M; Jones, S; Klaus, E; Bottaro, S; Garel, P; Saluvan, M; Bruneau, C; Depaigne-Loth, A; Shaw, C; Hammer, A; Ommen, O; Pfaff, H; Groene, O; Botje, D; Wagner, C; Kutaj-Wasikowska, H; Kutryba, B; Escoval, A; Lívio, A; Eiras, M; Franca, M; Leite, I; Almeman, F; Kus, H; Ozturk, K; Mannion, R; Arah, OA; Chow, A; DerSarkissian, M; Thompson, CA; Wang, A; Thompson, A

    2014-01-01

    Introduction and Objective This paper provides an overview of the DUQuE (Deepening our Understanding of Quality Improvement in Europe) project, the first study across multiple countries of the European Union (EU) to assess relationships between quality management and patient outcomes at EU level. The paper describes the conceptual framework and methods applied, highlighting the novel features of this study. Design DUQuE was designed as a multi-level cross-sectional study with data collection at hospital, pathway, professional and patient level in eight countries. Setting and Participants We aimed to collect data for the assessment of hospital-wide constructs from up to 30 randomly selected hospitals in each country, and additional data at pathway and patient level in 12 of these 30. Main outcome measures A comprehensive conceptual framework was developed to account for the multiple levels that influence hospital performance and patient outcomes. We assessed hospital-specific constructs (organizational culture and professional involvement), clinical pathway constructs (the organization of care processes for acute myocardial infarction, stroke, hip fracture and deliveries), patient-specific processes and outcomes (clinical effectiveness, patient safety and patient experience) and external constructs that could modify hospital quality (external assessment and perceived external pressure). Results Data was gathered from 188 hospitals in 7 participating countries. The overall participation and response rate were between 75% and 100% for the assessed measures. Conclusions This is the first study assessing relation between quality management and patient outcomes at EU level. The study involved a large number of respondents and achieved high response rates. This work will serve to develop guidance in how to assess quality management and makes recommendations on the best ways to improve quality in healthcare for hospital stakeholders, payers, researchers, and policy makers throughout the EU. PMID:24671120

  16. The Effects of the Fast Track Preventive Intervention on the Development of Conduct Disorder Across Childhood

    PubMed Central

    2013-01-01

    The impact of the Fast Track intervention on externalizing disorders across childhood was examined. Eight hundred-ninety-one early-starting children (69% male; 51% African American) were randomly assigned by matched sets of schools to intervention or control conditions. The 10-year intervention addressed parent behavior-management, child social cognitive skills, reading, home visiting, mentoring, and classroom curricula. Outcomes included psychiatric diagnoses after grades 3, 6, 9, and 12 for conduct disorder, oppositional defiant disorder, attention deficit hyperactivity disorder, and any externalizing disorder. Significant interaction effects between intervention and initial risk level indicated that intervention prevented the lifetime prevalence of all diagnoses, but only among those at highest initial risk, suggesting that targeted intervention can prevent externalizing disorders to promote the raising of healthy children. PMID:21291445

  17. The Effects of Slackline Balance Training on Postural Control in Older Adults.

    PubMed

    Thomas, Monika; Kalicinski, Michael

    2016-07-01

    The present study investigated whether slackline training enhances postural control in older adults. Twenty-four participants were randomized into an intervention and a control group. The intervention group received 6 weeks of slackline training, two times per week. Pre-post measurement included the time of different standing positions on a balance platform with and without an external disturbance and the acceleration of the balance platform. Results showed significantly improved standing times during one-leg stance without external disturbance and a significantly reduced acceleration of the balance platform for the intervention group after the training period during tandem stance with and without an external disturbance. We conclude that slackline training in older adults has a positive impact on postural control and thus on the reduction of fall risk.

  18. Dynamic control and information processing in chemical reaction systems by tuning self-organization behavior

    NASA Astrophysics Data System (ADS)

    Lebiedz, Dirk; Brandt-Pollmann, Ulrich

    2004-09-01

    Specific external control of chemical reaction systems and both dynamic control and signal processing as central functions in biochemical reaction systems are important issues of modern nonlinear science. For example nonlinear input-output behavior and its regulation are crucial for the maintainance of the life process that requires extensive communication between cells and their environment. An important question is how the dynamical behavior of biochemical systems is controlled and how they process information transmitted by incoming signals. But also from a general point of view external forcing of complex chemical reaction processes is important in many application areas ranging from chemical engineering to biomedicine. In order to study such control issues numerically, here, we choose a well characterized chemical system, the CO oxidation on Pt(110), which is interesting per se as an externally forced chemical oscillator model. We show numerically that tuning of temporal self-organization by input signals in this simple nonlinear chemical reaction exhibiting oscillatory behavior can in principle be exploited for both specific external control of dynamical system behavior and processing of complex information.

  19. Modification of the random forest algorithm to avoid statistical dependence problems when classifying remote sensing imagery

    NASA Astrophysics Data System (ADS)

    Cánovas-García, Fulgencio; Alonso-Sarría, Francisco; Gomariz-Castillo, Francisco; Oñate-Valdivieso, Fernando

    2017-06-01

    Random forest is a classification technique widely used in remote sensing. One of its advantages is that it produces an estimation of classification accuracy based on the so called out-of-bag cross-validation method. It is usually assumed that such estimation is not biased and may be used instead of validation based on an external data-set or a cross-validation external to the algorithm. In this paper we show that this is not necessarily the case when classifying remote sensing imagery using training areas with several pixels or objects. According to our results, out-of-bag cross-validation clearly overestimates accuracy, both overall and per class. The reason is that, in a training patch, pixels or objects are not independent (from a statistical point of view) of each other; however, they are split by bootstrapping into in-bag and out-of-bag as if they were really independent. We believe that putting whole patch, rather than pixels/objects, in one or the other set would produce a less biased out-of-bag cross-validation. To deal with the problem, we propose a modification of the random forest algorithm to split training patches instead of the pixels (or objects) that compose them. This modified algorithm does not overestimate accuracy and has no lower predictive capability than the original. When its results are validated with an external data-set, the accuracy is not different from that obtained with the original algorithm. We analysed three remote sensing images with different classification approaches (pixel and object based); in the three cases reported, the modification we propose produces a less biased accuracy estimation.

  20. American Brachytherapy Society Task Group Report: Combination of brachytherapy and external beam radiation for high-risk prostate cancer.

    PubMed

    Spratt, Daniel E; Soni, Payal D; McLaughlin, Patrick W; Merrick, Gregory S; Stock, Richard G; Blasko, John C; Zelefsky, Michael J

    To review outcomes for high-risk prostate cancer treated with combined modality radiation therapy (CMRT) utilizing external beam radiation therapy (EBRT) with a brachytherapy boost. The available literature for high-risk prostate cancer treated with combined modality radiation therapy was reviewed and summarized. At this time, the literature suggests that the majority of high-risk cancers are curable with multimodal treatment. Several large retrospective studies and three prospective randomized trials comparing CMRT to dose-escalated EBRT have demonstrated superior biochemical control with CMRT. Longer followup of the randomized trials will be required to determine if this will translate to a benefit in metastasis-free survival, disease-specific survival, and overall survival. Although greater toxicity has been associated with CMRT compared to EBRT, recent studies suggest that technological advances that allow better definition and sparing of critical adjacent structures as well as increasing experience with brachytherapy have improved implant quality and the toxicity profile of brachytherapy. The role of androgen deprivation therapy is well established in the external beam literature for high-risk disease, but there is controversy regarding the applicability of these data in the setting of dose escalation. At this time, there is not sufficient evidence for the omission of androgen deprivation therapy with dose escalation in this population. Comparisons with surgery remain limited by differences in patient selection, but the evidence would suggest better disease control with CMRT compared to surgery alone. Due to a series of technological advances, modern combination series have demonstrated unparalleled rates of disease control in the high-risk population. Given the evidence from recent randomized trials, combination therapy may become the standard of care for high-risk cancers. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  1. Online Problem Solving for Adolescent Brain Injury: A Randomized Trial of 2 Approaches.

    PubMed

    Wade, Shari L; Taylor, Hudson Gerry; Yeates, Keith Owen; Kirkwood, Michael; Zang, Huaiyu; McNally, Kelly; Stacin, Terry; Zhang, Nanhua

    Adolescent traumatic brain injury (TBI) contributes to deficits in executive functioning and behavior, but few evidence-based treatments exist. We conducted a randomized clinical trial comparing Teen Online Problem Solving with Family (TOPS-Family) with Teen Online Problem Solving with Teen Only (TOPS-TO) or the access to Internet Resources Comparison (IRC) group. Children, aged 11 to 18 years, who sustained a complicated mild-to-severe TBI in the previous 18 months were randomly assigned to the TOPS-Family (49), TOPS-TO (51), or IRC group (52). Parent and self-report measures of externalizing behaviors and executive functioning were completed before treatment and 6 months later. Treatment effects were examined using linear regression models, adjusting for baseline symptom levels. Age, maternal education, and family stresses were examined as moderators. The TOPS-Family group had lower levels of parent-reported executive dysfunction at follow-up than the TOPS-TO group, and differences between the TOPS-Family and IRC groups approached significance. Maternal education moderated improvements in parent-reported externalizing behaviors, with less educated parents in the TOPS-Family group reporting fewer symptoms. On the self-report Behavior Rating Inventory of Executive Functions, treatment efficacy varied with the level of parental stresses. The TOPS-Family group reported greater improvements at low stress levels, whereas the TOPS-TO group reported greater improvement at high-stress levels. The TOPS-TO group did not have significantly lower symptoms than the IRC group on any comparison. Findings support the efficacy of online family problem solving to address executive dysfunction and improve externalizing behaviors among youth with TBI from less advantaged households. Treatment with the teen alone may be indicated in high-stress families.

  2. High spatial resolution infrared camera as ISS external experiment

    NASA Astrophysics Data System (ADS)

    Eckehard, Lorenz; Frerker, Hap; Fitch, Robert Alan

    High spatial resolution infrared camera as ISS external experiment for monitoring global climate changes uses ISS internal and external resources (eg. data storage). The optical experiment will consist of an infrared camera for monitoring global climate changes from the ISS. This technology was evaluated by the German small satellite mission BIRD and further developed in different ESA projects. Compared to BIRD the presended instrument uses proven sensor advanced technologies (ISS external) and ISS on board processing and storage capabili-ties (internal). The instrument will be equipped with a serial interfaces for TM/TC and several relay commands for the power supply. For data processing and storage a mass memory is re-quired. The access to actual attitude data is highly desired to produce geo referenced maps-if possible by an on board processing.

  3. The impact of cognitive control, incentives, and working memory load on the P3 responses of externalizing prisoners.

    PubMed

    Baskin-Sommers, Arielle R; Krusemark, Elizabeth A; Curtin, John J; Lee, Christopher; Vujnovich, Aleice; Newman, Joseph P

    2014-02-01

    The P3 amplitude reduction is one of the most common correlates of externalizing. However, few studies have used experimental manipulations designed to challenge different cognitive functions in order to clarify the processes that impact this reduction. To examine factors moderating P3 amplitude in trait externalizing, we administered an n-back task that manipulated cognitive control demands, working memory load, and incentives to a sample of male offenders. Offenders with high trait externalizing scores did not display a global reduction in P3 amplitude. Rather, the negative association between trait externalizing and P3 amplitude was specific to trials involving inhibition of a dominant response during infrequent stimuli, in the context of low working memory load, and incentives for performance. In addition, we discuss the potential implications of these findings for externalizing-related psychopathologies. The results complement and expand previous work on the process-level dysfunction contributing to externalizing-related deficits in P3. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Orienting attention to visual or verbal/auditory imagery differentially impairs the processing of visual stimuli.

    PubMed

    Villena-González, Mario; López, Vladimir; Rodríguez, Eugenio

    2016-05-15

    When attention is oriented toward inner thoughts, as spontaneously occurs during mind wandering, the processing of external information is attenuated. However, the potential effects of thought's content regarding sensory attenuation are still unknown. The present study aims to assess if the representational format of thoughts, such as visual imagery or inner speech, might differentially affect the sensory processing of external stimuli. We recorded the brain activity of 20 participants (12 women) while they were exposed to a probe visual stimulus in three different conditions: executing a task on the visual probe (externally oriented attention), and two conditions involving inward-turned attention i.e. generating inner speech and performing visual imagery. Event-related potentials results showed that the P1 amplitude, related with sensory response, was significantly attenuated during both task involving inward attention compared with external task. When both representational formats were compared, the visual imagery condition showed stronger attenuation in sensory processing than inner speech condition. Alpha power in visual areas was measured as an index of cortical inhibition. Larger alpha amplitude was found when participants engaged in an internal thought contrasted with the external task, with visual imagery showing even more alpha power than inner speech condition. Our results show, for the first time to our knowledge, that visual attentional processing to external stimuli during self-generated thoughts is differentially affected by the representational format of the ongoing train of thoughts. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. A Stochastic Version of the Noether Theorem

    NASA Astrophysics Data System (ADS)

    González Lezcano, Alfredo; Cabo Montes de Oca, Alejandro

    2018-06-01

    A stochastic version of the Noether theorem is derived for systems under the action of external random forces. The concept of moment generating functional is employed to describe the symmetry of the stochastic forces. The theorem is applied to two kinds of random covariant forces. One of them generated in an electrodynamic way and the other is defined in the rest frame of the particle as a function of the proper time. For both of them, it is shown the conservation of the mean value of a random drift momentum. The validity of the theorem makes clear that random systems can produce causal stochastic correlations between two faraway separated systems, that had interacted in the past. In addition possible connections of the discussion with the Ives Couder's experimental results are remarked.

  6. External cues challenging the internal appetite control system-Overview and practical implications.

    PubMed

    Bilman, Els; van Kleef, Ellen; van Trijp, Hans

    2017-09-02

    Inadequate regulation of food intake plays an important role in the development of overweight and obesity, and is under the influence of both the internal appetite control system and external environmental cues. Especially in environments where food is overly available, external cues seem to override and/or undermine internal signals, which put severe challenges on the accurate regulation of food intake. By structuring these external cues around five different phases in the food consumption process this paper aims to provide an overview of the wide range of external cues that potentially facilitate or hamper internal signals and with that influence food intake. For each of the five phases of the food consumption process, meal initiation, meal planning, consumption phase, end of eating episode and time till next meal, the most relevant internal signals are discussed and it is explained how specific external cues exert their influence.

  7. Alternative mechanisms for regulating racial responses according to internal vs external cues.

    PubMed

    Amodio, David M; Kubota, Jennifer T; Harmon-Jones, Eddie; Devine, Patricia G

    2006-06-01

    Personal (internal) and normative (external) impetuses for regulating racially biased behaviour are well-documented, yet the extent to which internally and externally driven regulatory processes arise from the same mechanism is unknown. Whereas the regulation of race bias according to internal cues has been associated with conflict-monitoring processes and activation of the dorsal anterior cingulate cortex (dACC), we proposed that responses regulated according to external cues to respond without prejudice involves mechanisms of error-perception, a process associated with rostral anterior cingulate cortex (rACC) activity. We recruited low-prejudice participants who reported high or low sensitivity to non-prejudiced norms, and participants completed a stereotype inhibition task in private or public while electroencephalography was recorded. Analysis of event-related potentials revealed that the error-related negativity component, linked to dACC activity, predicted behavioural control of bias across conditions, whereas the error-perception component, linked to rACC activity, predicted control only in public among participants sensitive to external pressures to respond without prejudice.

  8. The variable polarity plasma arc welding process: Its application to the Space Shuttle external tank

    NASA Technical Reports Server (NTRS)

    Nunes, A. C., Jr.; Bayless, O. E., Jr.; Jones, C. S., III; Munafo, A. P.; Wilson, W. A.

    1983-01-01

    The technical history of the variable polarity plasma arc (VPPA) welding process being introduced as a partial replacement for the gas shielded tungsten arc process in assembly welding of the space shuttle external tank is described. Interim results of the weld strength qualification studies, and plans for further work on the implementation of the VPPA process are included.

  9. Biomedical journal speed and efficiency: a cross-sectional pilot survey of author experiences.

    PubMed

    Wallach, Joshua D; Egilman, Alexander C; Gopal, Anand D; Swami, Nishwant; Krumholz, Harlan M; Ross, Joseph S

    2018-01-01

    Although the peer review process is believed to ensure scientific rigor, enhance research quality, and improve manuscript clarity, many investigators are concerned that the process is too slow, too expensive, too unreliable, and too static. In this feasibility study, we sought to survey corresponding authors of recently published clinical research studies on the speed and efficiency of the publication process. Web-based survey of corresponding authors of a 20% random sample of clinical research studies in MEDLINE-indexed journals with Ovid MEDLINE entry dates between December 1 and 15, 2016. Survey addressed perceived manuscript importance before first submission, approximate first submission and final acceptance dates, and total number of journal submissions, external peer reviews, external peer reviewers, and revisions requested, as well as whether authors would have considered publicly sharing their manuscript on an online platform instead of submitting to a peer-reviewed journal. Of 1780 surveys distributed, 27 corresponding authors opted out or requested that we stop emailing them and 149 emails failed (e.g., emails that bounced n  = 64, returned with an away from office message n  = 70, or were changed/incorrect n  = 15), leaving 1604 respondents, of which 337 completed the survey (21.0%). Respondents and non-respondents were similar with respect to study type and publication journals' impact factor, although non-respondent authors had more publications ( p  = 0.03). Among respondents, the median impact factor of the publications' journal was 2.7 (interquartile range (IQR), 2.0-3.6) and corresponding authors' median h-index and number of publications was 9 (IQR, 3-20) and 27 (IQR, 10-77), respectively. The median time from first submission to journal acceptance and publication was 5 months (IQR, 3-8) and 7 months (IQR, 5-12), respectively. Most respondents (62.0%, n  = 209) rated the importance of their research as a 4 or 5 (5-point scale) prior to submission. Median number of journal submissions was 1 (IQR, 1-2), external peer reviews was 1 (IQR, 1-2), external peer reviewers was 3 (IQR, 2-4), and revisions requested was 1 (IQR, 1-1). Sharing manuscripts to a public online platform, instead of submitting to a peer-reviewed journal, would have been considered by 55.2% ( n  = 186) of respondents. Corresponding authors have high perceptions of their research and reported requiring few manuscript submissions prior to journal acceptance, most commonly by lower impact factor journals.

  10. Development and Implementation of a Formal Framework for Bottom-up Uncertainty Analysis of Input Emissions: Case Study of Residential Wood Combustion

    NASA Astrophysics Data System (ADS)

    Zhao, S.; Mashayekhi, R.; Saeednooran, S.; Hakami, A.; Ménard, R.; Moran, M. D.; Zhang, J.

    2016-12-01

    We have developed a formal framework for documentation, quantification, and propagation of uncertainties in upstream emissions inventory data at various stages leading to the generation of model-ready gridded emissions through emissions processing software such as the EPA's SMOKE (Sparse Matrix Operator Kernel Emissions) system. To illustrate this framework we present a proof-of-concept case study of a bottom-up quantitative assessment of uncertainties in emissions from residential wood combustion (RWC) in the U.S. and Canada. Uncertainties associated with key inventory parameters are characterized based on existing information sources, including the American Housing Survey (AHS) from the U.S. Census Bureau, Timber Products Output (TPO) surveys from the U.S. Forest Service, TNS Canadian Facts surveys, and the AP-42 emission factor document from the U.S. EPA. The propagation of uncertainties is based on Monte Carlo simulation code external to SMOKE. Latin Hypercube Sampling (LHS) is implemented to generate a set of random realizations of each RWC inventory parameter, for which the uncertainties are assumed to be normally distributed. Random realizations are also obtained for each RWC temporal and chemical speciation profile and spatial surrogate field external to SMOKE using the LHS approach. SMOKE outputs for primary emissions (e.g., CO, VOC) using both RWC emission inventory realizations and perturbed temporal and chemical profiles and spatial surrogates show relative uncertainties of about 30-50% across the U.S. and about 70-100% across Canada. Positive skewness values (up to 2.7) and variable kurtosis values (up to 4.8) were also found. Spatial allocation contributes significantly to the overall uncertainty, particularly in Canada. By applying this framework we are able to produce random realizations of model-ready gridded emissions that along with available meteorological ensembles can be used to propagate uncertainties through chemical transport models. The approach described here provides an effective means for formal quantification of uncertainties in estimated emissions from various source sectors and for continuous documentation, assessment, and reduction of emission uncertainties.

  11. Tocolysis in term breech external cephalic version.

    PubMed

    Nor Azlin, M I; Haliza, H; Mahdy, Z A; Anson, I; Fahya, M N; Jamil, M A

    2005-01-01

    To study the effect of ritodrine tocolysis on the success of external cephalic version (ECV) and to assess the role of ECV in breech presentation at our centre. A prospective randomized double-blind-controlled trial comparing ritodrine and placebo in ECV of singleton term breech pregnancy at a tertiary hospital. Among the 60 patients who were recruited, there was a success rate of 36.7%. Ritodrine tocolysis significantly improved the success rate of ECV (50% vs. 23%; P=0.032). There was a marked effect of ritodrine tocolysis on the ECV success in nulliparae (36.4% vs. 13.0%) and multiparae (87.5% vs. 57.1%). External cephalic version has shown to reduce the rate of cesarean section for breech presentation by 33.5% in our unit. External cephalic version significantly reduced the rate of cesarean section in breech presentation, and ritodrine tocolysis improved the success of ECV and should be offered to both nulliparous and parous women in the case of term breech presentation.

  12. Experimental and Quasi-Experimental Design.

    ERIC Educational Resources Information Center

    Cottrell, Edward B.

    With an emphasis on the problems of control of extraneous variables and threats to internal and external validity, the arrangement or design of experiments is discussed. The purpose of experimentation in an educational institution, and the principles governing true experimentation (randomization, replication, and control) are presented, as are…

  13. Emotional Design in Multimedia Learning

    ERIC Educational Resources Information Center

    Um, Eunjoon; Plass, Jan L.; Hayward, Elizabeth O.; Homer, Bruce D.

    2012-01-01

    Can multimedia learning environments be designed to foster positive emotions that will improve learning and related affective outcomes? College students (N = 118) were randomly assigned to 4 conditions created by 2 factors related to learners' emotion: "external mood induction" (positive vs. neutral emotions) and "emotional design induction"…

  14. Randomized Prospective Trial on the Occurrence of Laparoscopic Trocar Site Hernias

    ClinicalTrials.gov

    2010-11-12

    The Aim of the Study is to Analyze the Incidence of Trocar Site Hernia (TSH); in Orifices Created by Trocars Measuring ≥10 mm in Diameter,; and to Determine Whether Closure of the External Fascial Layer Prevents; TSH and Potential Related Complications.

  15. [The reentrant binomial model of nuclear anomalies growth in rhabdomyosarcoma RA-23 cell populations under increasing doze of rare ionizing radiation].

    PubMed

    Alekseeva, N P; Alekseev, A O; Vakhtin, Iu B; Kravtsov, V Iu; Kuzovatov, S N; Skorikova, T I

    2008-01-01

    Distributions of nuclear morphology anomalies in transplantable rabdomiosarcoma RA-23 cell populations were investigated under effect of ionizing radiation from 0 to 45 Gy. Internuclear bridges, nuclear protrusions and dumbbell-shaped nuclei were accepted for morphological anomalies. Empirical distributions of the number of anomalies per 100 nuclei were used. The adequate model of reentrant binomial distribution has been found. The sum of binomial random variables with binomial number of summands has such distribution. Averages of these random variables were named, accordingly, internal and external average reentrant components. Their maximum likelihood estimations were received. Statistical properties of these estimations were investigated by means of statistical modeling. It has been received that at equally significant correlation between the radiation dose and the average of nuclear anomalies in cell populations after two-three cellular cycles from the moment of irradiation in vivo the irradiation doze significantly correlates with internal average reentrant component, and in remote descendants of cell transplants irradiated in vitro - with external one.

  16. Dynamics of the Random Field Ising Model

    NASA Astrophysics Data System (ADS)

    Xu, Jian

    The Random Field Ising Model (RFIM) is a general tool to study disordered systems. Crackling noise is generated when disordered systems are driven by external forces, spanning a broad range of sizes. Systems with different microscopic structures such as disordered mag- nets and Earth's crust have been studied under the RFIM. In this thesis, we investigated the domain dynamics and critical behavior in two dipole-coupled Ising ferromagnets Nd2Fe14B and LiHoxY 1-xF4. With Tc well above room temperature, Nd2Fe14B has shown reversible disorder when exposed to an external transverse field and crosses between two universality classes in the strong and weak disorder limits. Besides tunable disorder, LiHoxY1-xF4 has shown quantum tunneling effects arising from quantum fluctuations, providing another mechanism for domain reversal. Universality within and beyond power law dependence on avalanche size and energy were studied in LiHo0.65Y0.35 F4.

  17. Incorporating external evidence in trial-based cost-effectiveness analyses: the use of resampling methods

    PubMed Central

    2014-01-01

    Background Cost-effectiveness analyses (CEAs) that use patient-specific data from a randomized controlled trial (RCT) are popular, yet such CEAs are criticized because they neglect to incorporate evidence external to the trial. A popular method for quantifying uncertainty in a RCT-based CEA is the bootstrap. The objective of the present study was to further expand the bootstrap method of RCT-based CEA for the incorporation of external evidence. Methods We utilize the Bayesian interpretation of the bootstrap and derive the distribution for the cost and effectiveness outcomes after observing the current RCT data and the external evidence. We propose simple modifications of the bootstrap for sampling from such posterior distributions. Results In a proof-of-concept case study, we use data from a clinical trial and incorporate external evidence on the effect size of treatments to illustrate the method in action. Compared to the parametric models of evidence synthesis, the proposed approach requires fewer distributional assumptions, does not require explicit modeling of the relation between external evidence and outcomes of interest, and is generally easier to implement. A drawback of this approach is potential computational inefficiency compared to the parametric Bayesian methods. Conclusions The bootstrap method of RCT-based CEA can be extended to incorporate external evidence, while preserving its appealing features such as no requirement for parametric modeling of cost and effectiveness outcomes. PMID:24888356

  18. Incorporating external evidence in trial-based cost-effectiveness analyses: the use of resampling methods.

    PubMed

    Sadatsafavi, Mohsen; Marra, Carlo; Aaron, Shawn; Bryan, Stirling

    2014-06-03

    Cost-effectiveness analyses (CEAs) that use patient-specific data from a randomized controlled trial (RCT) are popular, yet such CEAs are criticized because they neglect to incorporate evidence external to the trial. A popular method for quantifying uncertainty in a RCT-based CEA is the bootstrap. The objective of the present study was to further expand the bootstrap method of RCT-based CEA for the incorporation of external evidence. We utilize the Bayesian interpretation of the bootstrap and derive the distribution for the cost and effectiveness outcomes after observing the current RCT data and the external evidence. We propose simple modifications of the bootstrap for sampling from such posterior distributions. In a proof-of-concept case study, we use data from a clinical trial and incorporate external evidence on the effect size of treatments to illustrate the method in action. Compared to the parametric models of evidence synthesis, the proposed approach requires fewer distributional assumptions, does not require explicit modeling of the relation between external evidence and outcomes of interest, and is generally easier to implement. A drawback of this approach is potential computational inefficiency compared to the parametric Bayesian methods. The bootstrap method of RCT-based CEA can be extended to incorporate external evidence, while preserving its appealing features such as no requirement for parametric modeling of cost and effectiveness outcomes.

  19. Breaking the silos: The art documentation suite

    DOE PAGES

    Kutschke, Robert K.

    2015-12-23

    The art event-processing framework is used by almost all new experiments at Fermilab, and by several outside of Fermilab. All use art as an external product in the same sense that the compiler, ROOT, Geant4, CLHEP and boost are external products. The art team has embarked on a campaign to document art and develop training materials for new users. Many new users of art have little or no knowledge of C++, software engineering, build systems or the many external packages used by art or their experiments, such as ROOT, CLHEP, HEPPDT, and boost. To effectively teach art requires that themore » training materials include appropriate introductions to these topics as they are encountered. Experience has shown that simply referring readers to the existing native documentation does not work, too often a simple idea that they need to understand is described in a context that presumes prerequisites that are unimportant for a beginning user of art. There is the additional complication that the training materials must be presented in a way that does not presume knowledge of any of the experiments using art. Finally, new users of art arrive at random times throughout the year and the training materials must allow them to start to learn art at any time. This presentation will explain the strategies adopted by the art team to develop a documentation suite that complies with these boundary conditions. It will also show the present status of the documentation suite, including feedback the art team has received from pilot users.« less

  20. 75 FR 52597 - Availability of Interim Procedures for Federal External Review and Model Notices Relating to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-26

    ... Availability of Interim Procedures for Federal External Review and Model Notices Relating to Internal Claims... procedures for the Federal external review process and model notices both for internal claims and appeals and... (3) A notice of final external review decision. Model language for the description of the internal...

  1. Role of Dentate Gyrus in Aligning Internal Spatial Map to External Landmark

    ERIC Educational Resources Information Center

    Lee, Jong Won; Kim, Woon Ryoung; Sun, Woong; Jung, Min Whan

    2009-01-01

    Humans and animals form internal representations of external space based on their own body movement (dead reckoning) as well as external landmarks. It is poorly understood, however, how different types of information are integrated to form a unified representation of external space. To examine the role of dentate gyrus (DG) in this process, we…

  2. The effectiveness of external sensory cues in improving functional performance in individuals with Parkinson's disease: a systematic review with meta-analysis.

    PubMed

    Cassimatis, Constantine; Liu, Karen P Y; Fahey, Paul; Bissett, Michelle

    2016-09-01

    A systematic review with meta-analysis was performed to investigate the effect external sensory cued therapy on activities of daily living (ADL) performance that include walking and daily tasks such as dressing for individuals with Parkinson's disease (PD). A detailed computer-aided search of the literature was applied to MEDLINE, Cumulative Index to Nursing and Allied Health Literature, EMBASE and PubMed. Studies investigating the effects of external sensory cued therapy on ADL performance for individuals with PD in all stages of disease progression were collected. Relevant articles were critically reviewed and study results were synthesized by two independent researchers. A data-analysis method was used to extract data from selected articles. A meta-analysis was carried out for all randomized-controlled trials. Six studies with 243 individuals with PD were included in this review. All six studies yielded positive findings in favour of external sensory cues. The meta-analysis showed that external sensory cued therapy improved statistically after treatment (P=0.011) and at follow-up (P<0.001) for ADL performance. The results of this review provided evidence of an improvement in ADL performance in general in individuals with PD. It is recommended that clinicians incorporate external sensory into a training programme focused on improving daily task performance.

  3. Abnormal externally guided movement preparation in recent-onset schizophrenia is associated with impaired selective attention to external input.

    PubMed

    Smid, Henderikus G O M; Westenbroek, Joanna M; Bruggeman, Richard; Knegtering, Henderikus; Van den Bosch, Robert J

    2009-11-30

    Several theories propose that the primary cognitive impairment in schizophrenia concerns a deficit in the processing of external input information. There is also evidence, however, for impaired motor preparation in schizophrenia. This provokes the question whether the impaired motor preparation in schizophrenia is a secondary consequence of disturbed (selective) processing of the input needed for that preparation, or an independent primary deficit. The aim of the present study was to discriminate between these hypotheses, by investigating externally guided movement preparation in relation to selective stimulus processing. The sample comprised 16 recent-onset schizophrenia patients and 16 controls who performed a movement-precuing task. In this task, a precue delivered information about one, two or no parameters of a movement summoned by a subsequent stimulus. Performance measures and measures derived from the electroencephalogram showed that patients yielded smaller benefits from the precues and showed less cue-based preparatory activity in advance of the imperative stimulus than the controls, suggesting a response preparation deficit. However, patients also showed less activity reflecting selective attention to the precue. We therefore conclude that the existing evidence for an impairment of externally guided motor preparation in schizophrenia is most likely due to a deficit in selective attention to the external input, which lends support to theories proposing that the primary cognitive deficit in schizophrenia concerns the processing of input information.

  4. Automated identification of wound information in clinical notes of patients with heart diseases: Developing and validating a natural language processing application.

    PubMed

    Topaz, Maxim; Lai, Kenneth; Dowding, Dawn; Lei, Victor J; Zisberg, Anna; Bowles, Kathryn H; Zhou, Li

    2016-12-01

    Electronic health records are being increasingly used by nurses with up to 80% of the health data recorded as free text. However, only a few studies have developed nursing-relevant tools that help busy clinicians to identify information they need at the point of care. This study developed and validated one of the first automated natural language processing applications to extract wound information (wound type, pressure ulcer stage, wound size, anatomic location, and wound treatment) from free text clinical notes. First, two human annotators manually reviewed a purposeful training sample (n=360) and random test sample (n=1100) of clinical notes (including 50% discharge summaries and 50% outpatient notes), identified wound cases, and created a gold standard dataset. We then trained and tested our natural language processing system (known as MTERMS) to process the wound information. Finally, we assessed our automated approach by comparing system-generated findings against the gold standard. We also compared the prevalence of wound cases identified from free-text data with coded diagnoses in the structured data. The testing dataset included 101 notes (9.2%) with wound information. The overall system performance was good (F-measure is a compiled measure of system's accuracy=92.7%), with best results for wound treatment (F-measure=95.7%) and poorest results for wound size (F-measure=81.9%). Only 46.5% of wound notes had a structured code for a wound diagnosis. The natural language processing system achieved good performance on a subset of randomly selected discharge summaries and outpatient notes. In more than half of the wound notes, there were no coded wound diagnoses, which highlight the significance of using natural language processing to enrich clinical decision making. Our future steps will include expansion of the application's information coverage to other relevant wound factors and validation of the model with external data. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. The synergetic effect of UV rays on the decomposition of xylene in dielectric barrier discharge plasma and photocatalyst process

    NASA Astrophysics Data System (ADS)

    Li, Wenjuan; Gu, Zhenyu; Teng, Fuhua; Lu, Jianhai; Dong, Shibi; Miao, Xiaoping; Wu, Zhongbiao

    2018-06-01

    The degradation of xylene in the dielectric barrier discharge plasma and photocatalyst process was studied, focusing on the synergetic effect of UV rays from plasma process and external UV lamps on the decomposition of xylene. The results showed that xylene could be decomposed by the discharge process in plasma system, whereas the UV rays from plasma process was very weak. After adding TiO2, the removal efficiency of xylene and energy yield in plasma process were enhanced since energetic particles activated the catalysis of TiO2. The removal efficiency of xylene and energy field in plasma and photocatalyst process combined with external UV lamps were further enhanced attributed to the degradation effect of plasma, the catalysis of TiO2 activated by plasma, the photolysis of UV rays and the photocatalysis of photocatalyst. The synergetic effect of UV rays from external UV lamps was obvious.

  6. Risk moderation of a parent and student preventive alcohol intervention by adolescent and family factors: a cluster randomized trial.

    PubMed

    Verdurmen, Jacqueline E E; Koning, Ina M; Vollebergh, Wilma A M; van den Eijnden, Regina J J M; Engels, Rutger C M E

    2014-03-01

    To examine risk moderation of an alcohol intervention targeting parents and adolescents. A cluster randomized trial including 2937 Dutch early adolescents (m=12.68years, SD=0.51) and their parents randomized over four conditions: parent intervention, student intervention, combined parent-student intervention, and control group. 152 classes of 19 high schools in The Netherlands (2006). Moderators at baseline (adolescent: gender, educational level and externalizing behavior; parent: educational level and heavy alcohol use) were used to examine the differential effects of the interventions on onset of (heavy) weekly drinking at 22-month follow-up. The combined intervention effectively delayed the onset of weekly drinking in the general population of adolescents, and was particularly effective in delaying the onset of heavy weekly drinking in a higher-risk subsample of adolescents (i.e. those attending lower levels of education and reporting higher levels of externalizing behavior). Present and previous results have established the combined intervention to be universally effective in postponing weekly alcohol use among Dutch adolescents, with an added effect on postponing heavy weekly drinking in high risk subgroups. Therefore, implementation of this intervention in the general population of schools in The Netherlands is advised. NTR649. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. The random energy model in a magnetic field and joint source channel coding

    NASA Astrophysics Data System (ADS)

    Merhav, Neri

    2008-09-01

    We demonstrate that there is an intimate relationship between the magnetic properties of Derrida’s random energy model (REM) of spin glasses and the problem of joint source-channel coding in Information Theory. In particular, typical patterns of erroneously decoded messages in the coding problem have “magnetization” properties that are analogous to those of the REM in certain phases, where the non-uniformity of the distribution of the source in the coding problem plays the role of an external magnetic field applied to the REM. We also relate the ensemble performance (random coding exponents) of joint source-channel codes to the free energy of the REM in its different phases.

  8. Mass media influence spreading in social networks with community structure

    NASA Astrophysics Data System (ADS)

    Candia, Julián; Mazzitello, Karina I.

    2008-07-01

    We study an extension of Axelrod's model for social influence, in which cultural drift is represented as random perturbations, while mass media are introduced by means of an external field. In this scenario, we investigate how the modular structure of social networks affects the propagation of mass media messages across a society. The community structure of social networks is represented by coupled random networks, in which two random graphs are connected by intercommunity links. Considering inhomogeneous mass media fields, we study the conditions for successful message spreading and find a novel phase diagram in the multidimensional parameter space. These findings show that social modularity effects are of paramount importance for designing successful, cost-effective advertising campaigns.

  9. Use of a Linear Paul Trap to Study Random Noise-Induced Beam Degradation in High-Intensity Accelerators

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chung, Moses; Gilson, Erik P.; Davidson, Ronald C.

    2009-04-10

    A random noise-induced beam degradation that can affect intense beam transport over long propagation distances has been experimentally studied by making use of the transverse beam dynamics equivalence between an alternating-gradient (AG) focusing system and a linear Paul trap system. For the present studies, machine imperfections in the quadrupole focusing lattice are considered, which are emulated by adding small random noise on the voltage waveform of the quadrupole electrodes in the Paul trap. It is observed that externally driven noise continuously produces a nonthermal tail of trapped ions, and increases the transverse emittance almost linearly with the duration of themore » noise.« less

  10. A retrospective review of how nonconformities are expressed and finalized in external inspections of health-care facilities.

    PubMed

    Hovlid, Einar; Høifødt, Helge; Smedbråten, Bente; Braut, Geir Sverre

    2015-09-23

    External inspections are widely used in health care as a means of improving the quality of care. However, the way external inspections affect the involved organization is poorly understood. A better understanding of these processes is important to improve our understanding of the varying effects of external inspections in different organizations. In turn, this can contribute to the development of more effective ways of conducting inspections. The way the inspecting organization states their grounds for noncompliant behavior and subsequently follows up to enforce the necessary changes can have implications for the inspected organization's change process. We explore how inspecting organizations express and state their grounds for noncompliant behavior and how they follow up to enforce improvements. We conducted a retrospective review, in which we performed a content analysis of the documents from 36 external inspections in Norway. Our analysis was guided by Donabedian's structure, process, and outcome model. Deficiencies in the management system in combination with clinical work processes was considered as nonconformity by the inspecting organizations. Two characteristic patterns were identified in the way observations led to a statement of nonconformity: one in which it was clearly demonstrated how deficiencies in the management system could affect clinical processes, and one in which this connection was not demonstrated. Two characteristic patterns were also identified in the way the inspecting organization followed up and finalized their inspection: one in which the inspection was finalized solely based on the documented changes in structural deficiencies addressed in the nonconformity statement, and one based on the documented changes in structural and process deficiencies addressed in the nonconformity statement. External inspections are performed to improve the quality of care. To accomplish this aim, we suggest that nonconformities should be grounded by observations that clearly demonstrate how deficiencies in the management system might affect the clinical processes, and that the inspection should be finalized based on documented changes in both structural and process deficiencies addressed in the nonconformity statement.

  11. The stability of freak waves with regard to external impact and perturbation of initial data

    NASA Astrophysics Data System (ADS)

    Smirnova, Anna; Shamin, Roman

    2014-05-01

    We investigate solutions of the equations, describing freak waves, in perspective of stability with regard to external impact and perturbation of initial data. The modeling of freak waves is based on numerical solution of equations describing a non-stationary potential flow of the ideal fluid with a free surface. We consider the two-dimensional infinitely deep flow. For waves modeling we use the equations in conformal variables. The variant of these equations is offered in [1]. Mathematical correctness of these equations was discussed in [2]. These works establish the uniqueness of solutions, offer the effective numerical solution calculation methods, prove the numerical convergence of these methods. The important aspect of numerical modeling of freak waves is the stability of solutions, describing these waves. In this work we study the questions of stability with regards to external impact and perturbation of initial data. We showed the stability of freak waves numerical model, corresponding to the external impact. We performed series of computational experiments with various freak wave initial data and random external impact. This impact means the power density on free surface. In each experiment examine two waves: the wave that was formed by external impact and without one. In all the experiments we see the stability of equation`s solutions. The random external impact practically does not change the time of freak wave formation and its form. Later our work progresses to the investigation of solution's stability under perturbations of initial data. We take the initial data that provide a freak wave and get the numerical solution. In common we take the numerical solution of equation with perturbation of initial data. The computing experiments showed that the freak waves equations solutions are stable under perturbations of initial data.So we can make a conclusion that freak waves are stable relatively external perturbation and perturbation of initial data both. 1. Zakharov V.E., Dyachenko A.I., Vasilyev O.A. New method for numerical simulation of a nonstationary potential flow of incompressible fluid with a free surface// Eur. J.~Mech. B Fluids. 2002. V. 21. P. 283-291. 2. R.V. Shamin. Dynamics of an Ideal Liquid with a Free Surface in Conformal Variables // Journal of Mathematical Sciences, Vol. 160, No. 5, 2009. P. 537-678. 3. R.V. Shamin, V.E. Zakharov, A.I. Dyachenko. How probability for freak wave formation can be found // THE EUROPEAN PHYSICAL JOURNAL - SPECIAL TOPICS Volume 185, Number 1, 113-124, DOI: 10.1140/epjst/e2010-01242-y

  12. Mediators of Change for Multisystemic Therapy with Juvenile Sexual Offenders

    ERIC Educational Resources Information Center

    Henggeler, Scott W.; Letourneau, Elizabeth J.; Chapman, Jason E.; Borduin, Charles M.; Schewe, Paul A.; McCart, Michael R.

    2009-01-01

    The mediators of favorable multisystemic therapy (MST) outcomes achieved at 12 months postrecruitment were examined within the context of a randomized effectiveness trial with 127 juvenile sexual offenders and their caregivers. Outcome measures assessed youth delinquency, substance use, externalizing symptoms, and deviant sexual interest/risk…

  13. Spatial Bose-Einstein Condensation.

    ERIC Educational Resources Information Center

    Masut, Remo; Mullin, William J.

    1979-01-01

    Analyzes three examples of spatial Bose-Einstein condensations in which the particles macroscopically occupy the lowest localized state of an inhomogeneous external potential. The three cases are (1) a box with a small square potential well inside, (2) a harmonic oscillator potential, and (3) randomly sized trapping potentials caused by…

  14. Unsupervised learning on scientific ocean drilling datasets from the South China Sea

    NASA Astrophysics Data System (ADS)

    Tse, Kevin C.; Chiu, Hon-Chim; Tsang, Man-Yin; Li, Yiliang; Lam, Edmund Y.

    2018-06-01

    Unsupervised learning methods were applied to explore data patterns in multivariate geophysical datasets collected from ocean floor sediment core samples coming from scientific ocean drilling in the South China Sea. Compared to studies on similar datasets, but using supervised learning methods which are designed to make predictions based on sample training data, unsupervised learning methods require no a priori information and focus only on the input data. In this study, popular unsupervised learning methods including K-means, self-organizing maps, hierarchical clustering and random forest were coupled with different distance metrics to form exploratory data clusters. The resulting data clusters were externally validated with lithologic units and geologic time scales assigned to the datasets by conventional methods. Compact and connected data clusters displayed varying degrees of correspondence with existing classification by lithologic units and geologic time scales. K-means and self-organizing maps were observed to perform better with lithologic units while random forest corresponded best with geologic time scales. This study sets a pioneering example of how unsupervised machine learning methods can be used as an automatic processing tool for the increasingly high volume of scientific ocean drilling data.

  15. Understanding the Stress Process of Chinese- and Korean-American Breast Cancer Survivors

    PubMed Central

    Lim, Jung-won

    2017-01-01

    Guided by the stress process model (SPM), this study investigated the direct and indirect pathways of primary (negative self-image and life stress), secondary stressors (family communication strain) and family coping (external and internal) on mental health outcomes among Chinese- and Korean-American breast cancer survivors (BCS). A total of 156 Chinese- and Korean-American BCS were surveyed. Results showed primary and secondary stressors had a negative effect on better mental health outcomes. External coping was associated with better mental health. Family communication strain mediated the relationship between life stress and mental health outcomes. External coping mediated the relationship between family communication strain and mental health outcomes. Multi-group analysis revealed the stress process did not differ across ethnic groups. Findings suggest the SPM may be applicable to understand the stress process of Chinese-and Korean-American BCS and provide valuable insight into the role of family communication and external coping on mental health outcomes. PMID:26223968

  16. Associations between Positive Parenting Practices and Child Externalizing Behavior in Underserved Latino Immigrant Families

    PubMed Central

    Holtrop, Kendal; Smith, Sharde' Mcneil; Scott, Jenna C.

    2015-01-01

    This study examined whether five specific parenting practices (i.e., monitoring, discipline, skill encouragement, problem solving, and positive involvement) were associated with reduced child externalizing behaviors among a sample of Latino immigrant families. It utilized baseline data from 83 Latino couples with children participating in a larger randomized controlled trial of a culturally adapted parenting intervention. Results reveal that monitoring, discipline, skill encouragement, and problem solving each made independent contributions to the prediction of child externalizing behavior, although not all in the expected direction. Further analyses examining mothers and fathers separately suggest that mother-reported monitoring and father-reported discipline practices uniquely contributed to these findings. These results may have important implications for prevention and clinical intervention efforts with Latino immigrant families, including the cultural adaptation and implementation of parenting interventions with this underserved population. PMID:25287585

  17. Response to a small external force and fluctuations of a passive particle in a one-dimensional diffusive environment

    NASA Astrophysics Data System (ADS)

    Huveneers, François

    2018-04-01

    We investigate the long-time behavior of a passive particle evolving in a one-dimensional diffusive random environment, with diffusion constant D . We consider two cases: (a) The particle is pulled forward by a small external constant force and (b) there is no systematic bias. Theoretical arguments and numerical simulations provide evidence that the particle is eventually trapped by the environment. This is diagnosed in two ways: The asymptotic speed of the particle scales quadratically with the external force as it goes to zero, and the fluctuations scale diffusively in the unbiased environment, up to possible logarithmic corrections in both cases. Moreover, in the large D limit (homogenized regime), we find an important transient region giving rise to other, finite-size scalings, and we describe the crossover to the true asymptotic behavior.

  18. [Clinicofunctional condition and quality of life in patients with chronic obstructive pulmonary disease before and after outpatient treatment with fenspiride].

    PubMed

    Butorov, S I; Butorov, I V; Bodrug, N I; Krushka, S I; Tofan, E F

    2008-01-01

    To study effects of long-term administration of fenspiride in combination with broncholytic drugs on dynamics of clinical symptoms, external respiration function and quality of life in patients with chronic obstructive pulmonary disease (COPD). A comparative randomized trial of fenspiride used for 6 months in combination with broncholytic drugs enrolled 68 COPD patients. A clinical status, external respiration function were examined. Quality of life was evaluated with WHO questionnaire WHOQOL-100. Addition of fenspiride to combined treatment of COPD attenuates COPD symptoms, normalizes blood biochemistry, improves external respiration function, raises exercise tolerance. Quality of life improved by physical and mental state scales. Fenspiride addition to COPD treatment improves efficacy of the standard treatment and is recommended for treatment of COPD of stage I and II in combination with broncholytic drugs.

  19. Exogenous application of platelet-leukocyte gel during open subacromial decompression contributes to improved patient outcome. A prospective randomized double-blind study.

    PubMed

    Everts, P A; Devilee, R J J; Brown Mahoney, C; van Erp, A; Oosterbos, C J M; Stellenboom, M; Knape, J T A; van Zundert, A

    2008-01-01

    Platelet-leukocyte gel (PLG) is being used during various surgical procedures in an attempt to enhance the healing process. We studied the effects of PLG on postoperative recovery of patients undergoing open subacromial decompression (OSD). PLG was produced from platelet-leukocyte-rich plasma (P-LRP), prepared from a unit of whole blood. Forty patients were included in the study. Self-assessed evaluations, using the American Shoulder and Elbow Surgeons scoring system of activities of daily living (ADL), joint instability, pain levels, pain medications, and clinical evaluations for range of motion were conducted. Platelet and leukocyte counts were significantly increased in the P-LRP compared to baseline counts. Treated patients demonstrated decreased visual analog scales for pain and used significantly less pain medication, had an improved range of motion during passive forward elevation, external rotation, external rotation with arm at 90 degrees abduction, internal rotation, and cross body adduction compared to control patients (p < 0.001). No differences in the instability score were observed between the groups. Furthermore, treated patients performed more ADL (p < 0.05). In the PLG-treated group, recovery was faster and patients returned earlier to daily activities and also took less pain medication than control subjects. Copyright 2008 S. Karger AG, Basel.

  20. Correlational approach to study interactions between dust Brownian particles in a plasma

    NASA Astrophysics Data System (ADS)

    Lisin, E. A.; Vaulina, O. S.; Petrov, O. F.

    2018-01-01

    A general approach to the correlational analysis of Brownian motion of strongly coupled particles in open dissipative systems is described. This approach can be applied to the theoretical description of various non-ideal statistically equilibrium systems (including non-Hamiltonian systems), as well as for the analysis of experimental data. In this paper, we consider an application of the correlational approach to the problem of experimental exploring the wake-mediated nonreciprocal interactions in complex plasmas. We derive simple analytic equations, which allows one to calculate the gradients of forces acting on a microparticle due to each of other particles as well as the gradients of external field, knowing only the information on time-averaged correlations of particles displacements and velocities. We show the importance of taking dissipative and random processes into account, without which consideration of a system with a nonreciprocal interparticle interaction as linearly coupled oscillators leads to significant errors in determining the characteristic frequencies in a system. In the examples of numerical simulations, we demonstrate that the proposed original approach could be an effective instrument in exploring the longitudinal wake structure of a microparticle in a plasma. Unlike the previous attempts to study the wake-mediated interactions in complex plasmas, our method does not require any external perturbations and is based on Brownian motion analysis only.

  1. Student Learning about Biomolecular Self-Assembly Using Two Different External Representations

    PubMed Central

    Höst, Gunnar E.; Larsson, Caroline; Olson, Arthur; Tibell, Lena A. E.

    2013-01-01

    Self-assembly is the fundamental but counterintuitive principle that explains how ordered biomolecular complexes form spontaneously in the cell. This study investigated the impact of using two external representations of virus self-assembly, an interactive tangible three-dimensional model and a static two-dimensional image, on student learning about the process of self-assembly in a group exercise. A conceptual analysis of self-assembly into a set of facets was performed to support study design and analysis. Written responses were collected in a pretest/posttest experimental design with 32 Swedish university students. A quantitative analysis of close-ended items indicated that the students improved their scores between pretest and posttest, with no significant difference between the conditions (tangible model/image). A qualitative analysis of an open-ended item indicated students were unfamiliar with self-assembly prior to the study. Students in the tangible model condition used the facets of self-assembly in their open-ended posttest responses more frequently than students in the image condition. In particular, it appears that the dynamic properties of the tangible model may support student understanding of self-assembly in terms of the random and reversible nature of molecular interactions. A tentative difference was observed in response complexity, with more multifaceted responses in the tangible model condition. PMID:24006395

  2. Complex-energy approach to sum rules within nuclear density functional theory

    DOE PAGES

    Hinohara, Nobuo; Kortelainen, Markus; Nazarewicz, Witold; ...

    2015-04-27

    The linear response of the nucleus to an external field contains unique information about the effective interaction, correlations governing the behavior of the many-body system, and properties of its excited states. To characterize the response, it is useful to use its energy-weighted moments, or sum rules. By comparing computed sum rules with experimental values, the information content of the response can be utilized in the optimization process of the nuclear Hamiltonian or nuclear energy density functional (EDF). But the additional information comes at a price: compared to the ground state, computation of excited states is more demanding. To establish anmore » efficient framework to compute energy-weighted sum rules of the response that is adaptable to the optimization of the nuclear EDF and large-scale surveys of collective strength, we have developed a new technique within the complex-energy finite-amplitude method (FAM) based on the quasiparticle random- phase approximation. The proposed sum-rule technique based on the complex-energy FAM is a tool of choice when optimizing effective interactions or energy functionals. The method is very efficient and well-adaptable to parallel computing. As a result, the FAM formulation is especially useful when standard theorems based on commutation relations involving the nuclear Hamiltonian and external field cannot be used.« less

  3. Student learning about biomolecular self-assembly using two different external representations.

    PubMed

    Höst, Gunnar E; Larsson, Caroline; Olson, Arthur; Tibell, Lena A E

    2013-01-01

    Self-assembly is the fundamental but counterintuitive principle that explains how ordered biomolecular complexes form spontaneously in the cell. This study investigated the impact of using two external representations of virus self-assembly, an interactive tangible three-dimensional model and a static two-dimensional image, on student learning about the process of self-assembly in a group exercise. A conceptual analysis of self-assembly into a set of facets was performed to support study design and analysis. Written responses were collected in a pretest/posttest experimental design with 32 Swedish university students. A quantitative analysis of close-ended items indicated that the students improved their scores between pretest and posttest, with no significant difference between the conditions (tangible model/image). A qualitative analysis of an open-ended item indicated students were unfamiliar with self-assembly prior to the study. Students in the tangible model condition used the facets of self-assembly in their open-ended posttest responses more frequently than students in the image condition. In particular, it appears that the dynamic properties of the tangible model may support student understanding of self-assembly in terms of the random and reversible nature of molecular interactions. A tentative difference was observed in response complexity, with more multifaceted responses in the tangible model condition.

  4. Current fluctuations in periodically driven systems

    NASA Astrophysics Data System (ADS)

    Barato, Andre C.; Chetrite, Raphael

    2018-05-01

    Small nonequelibrium systems driven by an external periodic protocol can be described by Markov processes with time-periodic transition rates. In general, current fluctuations in such small systems are large and may play a crucial role. We develop a theoretical formalism to evaluate the rate of such large deviations in periodically driven systems. We show that the scaled cumulant generating function that characterizes current fluctuations is given by a maximal Floquet exponent. Comparing deterministic protocols with stochastic protocols, we show that, with respect to large deviations, systems driven by a stochastic protocol with an infinitely large number of jumps are equivalent to systems driven by deterministic protocols. Our results are illustrated with three case studies: a two-state model for a heat engine, a three-state model for a molecular pump, and a biased random walk with a time-periodic affinity.

  5. Radio Frequency Interference Detection using Machine Learning.

    NASA Astrophysics Data System (ADS)

    Mosiane, Olorato; Oozeer, Nadeem; Aniyan, Arun; Bassett, Bruce A.

    2017-05-01

    Radio frequency interference (RFI) has plagued radio astronomy which potentially might be as bad or worse by the time the Square Kilometre Array (SKA) comes up. RFI can be either internal (generated by instruments) or external that originates from intentional or unintentional radio emission generated by man. With the huge amount of data that will be available with up coming radio telescopes, an automated aproach will be required to detect RFI. In this paper to try automate this process we present the result of applying machine learning techniques to cross match RFI from the Karoo Array Telescope (KAT-7) data. We found that not all the features selected to characterise RFI are always important. We further investigated 3 machine learning techniques and conclude that the Random forest classifier performs with a 98% Area Under Curve and 91% recall in detecting RFI.

  6. The NSO FTS database program and archive (FTSDBM)

    NASA Technical Reports Server (NTRS)

    Lytle, D. M.

    1992-01-01

    Data from the NSO Fourier transform spectrometer is being re-archived from half inch tape onto write-once compact disk. In the process, information about each spectrum and a low resolution copy of each spectrum is being saved into an on-line database. FTSDBM is a simple database management program in the NSO external package for IRAF. A command language allows the FTSDBM user to add entries to the database, delete entries, select subsets from the database based on keyword values including ranges of values, create new database files based on these subsets, make keyword lists, examine low resolution spectra graphically, and make disk number/file number lists. Once the archive is complete, FTSDBM will allow the database to be efficiently searched for data of interest to the user and the compact disk format will allow random access to that data.

  7. Control of variable speed variable pitch wind turbine based on a disturbance observer

    NASA Astrophysics Data System (ADS)

    Ren, Haijun; Lei, Xin

    2017-11-01

    In this paper, a novel sliding mode controller based on disturbance observer (DOB) to optimize the efficiency of variable speed variable pitch (VSVP) wind turbine is developed and analyzed. Due to the highly nonlinearity of the VSVP system, the model is linearly processed to obtain the state space model of the system. Then, a conventional sliding mode controller is designed and a DOB is added to estimate wind speed. The proposed control strategy can successfully deal with the random nature of wind speed, the nonlinearity of VSVP system, the uncertainty of parameters and external disturbance. Via adding the observer to the sliding mode controller, it can greatly reduce the chattering produced by the sliding mode switching gain. The simulation results show that the proposed control system has the effectiveness and robustness.

  8. The Relationships Between Internal and External Measures of Training Load and Intensity in Team Sports: A Meta-Analysis.

    PubMed

    McLaren, Shaun J; Macpherson, Tom W; Coutts, Aaron J; Hurst, Christopher; Spears, Iain R; Weston, Matthew

    2018-03-01

    The associations between internal and external measures of training load and intensity are important in understanding the training process and the validity of specific internal measures. We aimed to provide meta-analytic estimates of the relationships, as determined by a correlation coefficient, between internal and external measures of load and intensity during team-sport training and competition. A further aim was to examine the moderating effects of training mode on these relationships. We searched six electronic databases (Scopus, Web of Science, PubMed, MEDLINE, SPORTDiscus, CINAHL) for original research articles published up to September 2017. A Boolean search phrase was created to include search terms relevant to team-sport athletes (population; 37 keywords), internal load (dependent variable; 35 keywords), and external load (independent variable; 81 keywords). Articles were considered for meta-analysis when a correlation coefficient describing the association between at least one internal and one external measure of session load or intensity, measured in the time or frequency domain, was obtained from team-sport athletes during normal training or match-play (i.e., unstructured observational study). The final data sample included 122 estimates from 13 independent studies describing 15 unique relationships between three internal and nine external measures of load and intensity. This sample included 295 athletes and 10,418 individual session observations. Internal measures were session ratings of perceived exertion (sRPE), sRPE training load (sRPE-TL), and heart-rate-derived training impulse (TRIMP). External measures were total distance (TD), the distance covered at high and very high speeds (HSRD ≥ 13.1-15.0 km h -1 and VHSRD ≥ 16.9-19.8 km h -1 , respectively), accelerometer load (AL), and the number of sustained impacts (Impacts > 2-5 G). Distinct training modes were identified as either mixed (reference condition), skills, metabolic, or neuromuscular. Separate random effects meta-analyses were conducted for each dataset (n = 15) to determine the pooled relationships between internal and external measures of load and intensity. The moderating effects of training mode were examined using random-effects meta-regression for datasets with at least ten estimates (n = 4). Magnitude-based inferences were used to interpret analyses outcomes. During all training modes combined, the external load relationships for sRPE-TL were possibly very large with TD [r = 0.79; 90% confidence interval (CI) 0.74 to 0.83], possibly large with AL (r = 0.63; 90% CI 0.54 to 0.70) and Impacts (r = 0.57; 90% CI 0.47 to 0.64), and likely moderate with HSRD (r = 0.47; 90% CI 0.32 to 0.59). The relationship between TRIMP and AL was possibly large (r = 0.54; 90% CI 0.40 to 0.66). All other relationships were unclear or not possible to infer (r range 0.17-0.74, n = 10 datasets). Between-estimate heterogeneity [standard deviations (SDs) representing unexplained variation; τ] in the pooled internal-external relationships were trivial to extremely large for sRPE (τ range = 0.00-0.47), small to large for sRPE-TL (τ range = 0.07-0.31), and trivial to moderate for TRIMP (τ range= 0.00-0.17). The internal-external load relationships during mixed training were possibly very large for sRPE-TL with TD (r = 0.82; 90% CI 0.75 to 0.87) and AL (r = 0.81; 90% CI 0.74 to 0.86), and TRIMP with AL (r = 0.72; 90% CI 0.55 to 0.84), and possibly large for sRPE-TL with HSRD (r = 0.65; 90% CI 0.44 to 0.80). A reduction in these correlation magnitudes was evident for all other training modes (range of the change in r when compared with mixed training - 0.08 to - 0.58), with these differences being unclear to possibly large. Training mode explained 24-100% of the between-estimate variance in the internal-external load relationships. Measures of internal load derived from perceived exertion and heart rate show consistently positive associations with running- and accelerometer-derived external loads and intensity during team-sport training and competition, but the magnitude and uncertainty of these relationships are measure and training mode dependent.

  9. Domain Wall Depinning in Random Media by ac Fields

    NASA Astrophysics Data System (ADS)

    Glatz, A.; Nattermann, T.; Pokrovsky, V.

    2003-01-01

    The viscous motion of an interface driven by an ac external field of frequency ω0 in a random medium is considered here in the nonadiabatic regime. The velocity exhibits a smeared depinning transition showing a double hysteresis which is absent in the adiabatic case ω0→0. Using scaling arguments and an approximate renormalization group calculation we explain the main characteristics of the hysteresis loop. In the low frequency limit these can be expressed in terms of the depinning threshold and the critical exponents of the adiabatic case.

  10. Quantitative analysis of random ameboid motion

    NASA Astrophysics Data System (ADS)

    Bödeker, H. U.; Beta, C.; Frank, T. D.; Bodenschatz, E.

    2010-04-01

    We quantify random migration of the social ameba Dictyostelium discoideum. We demonstrate that the statistics of cell motion can be described by an underlying Langevin-type stochastic differential equation. An analytic expression for the velocity distribution function is derived. The separation into deterministic and stochastic parts of the movement shows that the cells undergo a damped motion with multiplicative noise. Both contributions to the dynamics display a distinct response to external physiological stimuli. The deterministic component depends on the developmental state and ambient levels of signaling substances, while the stochastic part does not.

  11. Random bearings and their stability.

    PubMed

    Mahmoodi Baram, Reza; Herrmann, Hans J

    2005-11-25

    Self-similar space-filling bearings have been proposed some time ago as models for the motion of tectonic plates and appearance of seismic gaps. These models have two features which, however, seem unrealistic, namely, high symmetry in the arrangement of the particles, and lack of a lower cutoff in the size of the particles. In this work, an algorithm for generating random bearings in both two and three dimensions is presented. Introducing a lower cutoff for the sizes of the particles, the instabilities of the bearing under an external force such as gravity, are studied.

  12. Selected KSC Applied Physics Lab Responses to Shuttle Processing Measurement Requests

    NASA Technical Reports Server (NTRS)

    Youngquist, Robert C.

    2010-01-01

    The KSC Applied Physics Lab has been supporting Shuttle Ground Processing for over 20 years by solving problems brought to us by Shuttle personnel. Roughly half of the requests to our lab have been to find ways to make measurements, or to improve on an existing measurement process. This talk will briefly cover: 1) Centering the aft end of the External Tank between the Solid Rocket Boosters; 2) Positioning the GOX Vent Hood over the External Tank; 3) Remote Measurements of External Tank Damage; 4) Strain Measurement in the Orbiter Sling; and 5) Over-center Distance Measurement in an Over-center Mechanism.

  13. Implementation of the external cephalic version in breech delivery. Dutch national implementation study of external cephalic version.

    PubMed

    Vlemmix, Floortje; Rosman, Ageeth N; Fleuren, Margot A H; Rijnders, Marlies E B; Beuckens, Antje; Haak, Monique C; Akerboom, Bettina M C; Bais, Joke M J; Kuppens, Simone M I; Papatsonis, Dimitri N; Opmeer, Brent C; van der Post, Joris A M; Mol, Ben Willem J; Kok, Marjolein

    2010-05-10

    Breech presentation occurs in 3 to 4% of all term pregnancies. External cephalic version (ECV) is proven effective to prevent vaginal breech deliveries and therefore it is recommended by clinical guidelines of the Royal Dutch Organisation for Midwives (KNOV) and the Dutch Society for Obstetrics and Gynaecology (NVOG). Implementation of ECV does not exceed 50 to 60% and probably less.We aim to improve the implementation of ECV to decrease maternal and neonatal morbidity and mortality due to breech presentations. This will be done by defining barriers and facilitators of implementation of ECV in the Netherlands. An innovative implementation strategy will be developed based on improved patient counselling and thorough instructions of health care providers for counselling. The ultimate purpose of this implementation study is to improve counselling of pregnant women and information of clinicians to realize a better implementation of ECV.The first phase of the project is to detect the barriers and facilitators of ECV. The next step is to develop an implementation strategy to inform and counsel pregnant women with a breech presentation, and to inform and educate care providers. In the third phase, the effectiveness of the developed implementation strategy will be evaluated in a randomised trial. The study population is a random selection of midwives and gynaecologists from 60 to 100 hospitals and practices. Primary endpoints are number of counselled women. Secondary endpoints are process indicators, the amount of fetes in cephalic presentation at birth, complications due to ECV, the number of caesarean sections and perinatal condition of mother and child. Cost effectiveness of the implementation strategy will be measured. This study will provide evidence for the cost effectiveness of a structural implementation of external cephalic versions to reduce the number of breech presentations at term. Dutch Trial Register (NTR): 1878.

  14. Implementation of the external cephalic version in breech delivery. Dutch national implementation study of external cephalic version

    PubMed Central

    2010-01-01

    Background Breech presentation occurs in 3 to 4% of all term pregnancies. External cephalic version (ECV) is proven effective to prevent vaginal breech deliveries and therefore it is recommended by clinical guidelines of the Royal Dutch Organisation for Midwives (KNOV) and the Dutch Society for Obstetrics and Gynaecology (NVOG). Implementation of ECV does not exceed 50 to 60% and probably less. We aim to improve the implementation of ECV to decrease maternal and neonatal morbidity and mortality due to breech presentations. This will be done by defining barriers and facilitators of implementation of ECV in the Netherlands. An innovative implementation strategy will be developed based on improved patient counselling and thorough instructions of health care providers for counselling. Method/design The ultimate purpose of this implementation study is to improve counselling of pregnant women and information of clinicians to realize a better implementation of ECV. The first phase of the project is to detect the barriers and facilitators of ECV. The next step is to develop an implementation strategy to inform and counsel pregnant women with a breech presentation, and to inform and educate care providers. In the third phase, the effectiveness of the developed implementation strategy will be evaluated in a randomised trial. The study population is a random selection of midwives and gynaecologists from 60 to 100 hospitals and practices. Primary endpoints are number of counselled women. Secondary endpoints are process indicators, the amount of fetes in cephalic presentation at birth, complications due to ECV, the number of caesarean sections and perinatal condition of mother and child. Cost effectiveness of the implementation strategy will be measured. Discussion This study will provide evidence for the cost effectiveness of a structural implementation of external cephalic versions to reduce the number of breech presentations at term. Trial Registration Dutch Trial Register (NTR): 1878 PMID:20459717

  15. Detecting effects of the indicated prevention Programme for Externalizing Problem behaviour (PEP) on child symptoms, parenting, and parental quality of life in a randomized controlled trial.

    PubMed

    Hanisch, Charlotte; Freund-Braier, Inez; Hautmann, Christopher; Jänen, Nicola; Plück, Julia; Brix, Gabriele; Eichelberger, Ilka; Döpfner, Manfred

    2010-01-01

    Behavioural parent training is effective in improving child disruptive behavioural problems in preschool children by increasing parenting competence. The indicated Prevention Programme for Externalizing Problem behaviour (PEP) is a group training programme for parents and kindergarten teachers of children aged 3-6 years with externalizing behavioural problems. To evaluate the effects of PEP on child problem behaviour, parenting practices, parent-child interactions, and parental quality of life. Parents and kindergarten teachers of 155 children were randomly assigned to an intervention group (n = 91) and a nontreated control group (n = 64). They rated children's problem behaviour before and after PEP training; parents also reported on their parenting practices and quality of life. Standardized play situations were video-taped and rated for parent-child interactions, e.g. parental warmth. In the intention to treat analysis, mothers of the intervention group described less disruptive child behaviour and better parenting strategies, and showed more parental warmth during a standardized parent-child interaction. Dosage analyses confirmed these results for parents who attended at least five training sessions. Children were also rated to show less behaviour problems by their kindergarten teachers. Training effects were especially positive for parents who attended at least half of the training sessions. CBCL: Child Behaviour Checklist; CII: Coder Impressions Inventory; DASS: Depression anxiety Stress Scale; HSQ: Home-situation Questionnaire; LSS: Life Satisfaction Scale; OBDT: observed behaviour during the test; PCL: Problem Checklist; PEP: prevention programme for externalizing problem behaviour; PPC: Parent Problem Checklist; PPS: Parent Practices Scale; PS: Parenting Scale; PSBC: Problem Setting and Behaviour checklist; QJPS: Questionnaire on Judging Parental Strains; SEFS: Self-Efficacy Scale; SSC: Social Support Scale; TRF: Caregiver-Teacher Report Form.

  16. Quality of Life Effects of Automatic External Defibrillators in the Home: Results from the Home Automatic External Defibrillator Trial (HAT)

    PubMed Central

    Mark, Daniel B.; Anstrom, Kevin J.; McNulty, Steven E.; Flaker, Greg C.; Tonkin, Andrew M.; Smith, Warren M.; Toff, William D.; Dorian, Paul; Clapp-Channing, Nancy E.; Anderson, Jill; Johnson, George; Schron, Eleanor B.; Poole, Jeanne E.; Lee, Kerry L.; Bardy, Gust H.

    2010-01-01

    Background Public access automatic external defibrillators (AEDs) can save lives, but most deaths from out-of-hospital sudden cardiac arrest occur at home. The Home Automatic External Defibrillator Trial (HAT) found no survival advantage for adding a home AED to cardiopulmonary resuscitation (CPR) training for 7001 patients with a prior anterior wall myocardial infarction. Quality of life (QOL) outcomes for both the patient and spouse/companion were secondary endpoints. Methods A subset of 1007 study patients and their spouse/companions was randomly selected for ascertainment of QOL by structured interview at baseline and 12 and 24 months following enrollment. The primary QOL measures were the Medical Outcomes Study 36-Item Short-Form (SF-36) psychological well-being (reflecting anxiety and depression) and vitality (reflecting energy and fatigue) subscales. Results For patients and spouse/companions, the psychological well-being and vitality scales did not differ significantly between those randomly assigned an AED plus CPR training and controls who received CPR training only. None of the other QOL measures collected showed a clinically and statistically significant difference between treatment groups. Patients in the AED group were more likely to report being extremely or quite a bit reassured by their treatment assignment. Spouse/companions in the AED group reported being less often nervous about the possibility of using AED/CPR treatment than those in the CPR group. Conclusions Adding access to a home AED to CPR training did not affect quality of life either for patients with a prior anterior myocardial infarction or their spouse/companion but did provide more reassurance to the patients without increasing anxiety for spouse/companions. PMID:20362722

  17. Radiofrequency in female external genital cosmetics and sexual function: a randomized clinical trial.

    PubMed

    Lordêlo, Patrícia; Leal, Mariana Robatto Dantas; Brasil, Cristina Aires; Santos, Juliana Menezes; Lima, Maria Clara Neves Pavie Cardoso; Sartori, Marair Gracio Ferreira

    2016-11-01

    Female sexual behavior goes through cultural changes constantly, and recently, some women have shown the desire the ideal genitalia. In this study, we aimed to evaluate clinical responses to nonablative radiofrequency (RF) in terms of its cosmetic outcome in the female external genitalia and its effect on sexual function. A single-masking randomized controlled trial was conducted in 43 women (29 sexually active) who were unsatisfied with the appearance of their external genitalia. The women were divided into an RF group (n = 21, 14 sexually active) and a control group (n = 22, 15 sexually active). Eight sessions of RF were performed once a week. Photographs (taken before the first session and 8 days after the last session) were evaluated by the women and three blinded health professionals by using two 3-point Likert scales (unsatisfied, unchanged, and satisfied; and worst, unchanged, and improved). Sexual function was evaluated using the Female Sexual Function Index (FSFI) and analyzed using the Student t test. Women's satisfaction and health professional evaluation were analyzed using the chi-square test and inter- and intragroup binomial comparisons. Satisfaction response rates were 76 and 27 % for the RF and control groups, respectively (p = 0.001). All professionals found a clinical improvement association in the treated group with RF in comparison with the control group (p < 0.01). The overall FSFI sexual function score increased by 3.51 points in the RF group vs 0.1 points in the control group (p = 0.003). RF is an alternative for attaining a cosmetic outcome for the female external genitalia, with positives changes in patients' satisfaction and FSFI scores.

  18. Culture cultivating culture: the four products of the meaning-made world.

    PubMed

    Carriere, Kevin R

    2014-09-01

    Culture, in a semiotic cultural psychology, is defined from the viewpoint of cultivation--the meaning making processes that give meaning to the world (Valsiner 2000, 2007a). However, the individual is not simply a process-machine in an empty world--there are both the external outcomes of meaning making (individual and group based) as well as the collective influence on the cultivation process. I argue to examine the cultivation process more completely, one must look at these external influences that catalyze future cultivation processes. By examining the power of the external (environmental Umwelten) and group-internal (myths, morals), a much greater understanding of the behavior of individuals can be accomplished beyond examining the individual's process of meaning making. Further work into examining the objects that affectively activate the individual as well as group action and meaning making is called for and examples of such studies are given.

  19. Preparation research of Nano-SiC/Ni-P composite coating under a compound field

    NASA Astrophysics Data System (ADS)

    Zhou, H. Z.; Wang, W. H.; Gu, Y. Q.; Liu, R.; Zhao, M. L.

    2016-07-01

    In this paper, the preparation process of Ni-P-SiC composite coatings on 45 steel surfaces with the assistance of magnetic and ultrasound fields was researched. The influence of external field on the surface morphology and performance of the composite layer is also discussed. Experimental results showed that when prepared under magnetic and ultrasonic fields, composite layers are significantly more dense and uniform than coatings made without external fields. Nano-SiC particles, dispersed uniformly in the layer, significantly improve the hardness of the composite layer, and the composite layer under the external field had the highest hardness at 680 HV The external fields can also accelerate deposition and increase the thickness of the layer. Compared to layers processed without the assistance of external fields, the thickness of the layers increased by nearly ten µm.

  20. Epidemic transmission on random mobile network with diverse infection periods

    NASA Astrophysics Data System (ADS)

    Li, Kezan; Yu, Hong; Zeng, Zhaorong; Ding, Yong; Ma, Zhongjun

    2015-05-01

    The heterogeneity of individual susceptibility and infectivity and time-varying topological structure are two realistic factors when we study epidemics on complex networks. Current research results have shown that the heterogeneity of individual susceptibility and infectivity can increase the epidemic threshold in a random mobile dynamical network with the same infection period. In this paper, we will focus on random mobile dynamical networks with diverse infection periods due to people's different constitutions and external circumstances. Theoretical results indicate that the epidemic threshold of the random mobile network with diverse infection periods is larger than the counterpart with the same infection period. Moreover, the heterogeneity of individual susceptibility and infectivity can play a significant impact on disease transmission. In particular, the homogeneity of individuals will avail to the spreading of epidemics. Numerical examples verify further our theoretical results very well.

  1. Patterns and reliability of EEG during error monitoring for internal versus external feedback in schizophrenia.

    PubMed

    Llerena, Katiah; Wynn, Jonathan K; Hajcak, Greg; Green, Michael F; Horan, William P

    2016-07-01

    Accurately monitoring one's performance on daily life tasks, and integrating internal and external performance feedback are necessary for guiding productive behavior. Although internal feedback processing, as indexed by the error-related negativity (ERN), is consistently impaired in schizophrenia, initial findings suggest that external performance feedback processing, as indexed by the feedback negativity (FN), may actually be intact. The current study evaluated internal and external feedback processing task performance and test-retest reliability in schizophrenia. 92 schizophrenia outpatients and 63 healthy controls completed a flanker task (ERN) and a time estimation task (FN). Analyses examined the ΔERN and ΔFN defined as difference waves between correct/positive versus error/negative feedback conditions. A temporal principal component analysis was conducted to distinguish the ΔERN and ΔFN from overlapping neural responses. We also assessed test-retest reliability of ΔERN and ΔFN in patients over a 4-week interval. Patients showed reduced ΔERN accompanied by intact ΔFN. In patients, test-retest reliability for both ΔERN and ΔFN over a four-week period was fair to good. Individuals with schizophrenia show a pattern of impaired internal, but intact external, feedback processing. This pattern has implications for understanding the nature and neural correlates of impaired feedback processing in schizophrenia. Published by Elsevier B.V.

  2. Protocol: Adaptive Implementation of Effective Programs Trial (ADEPT): cluster randomized SMART trial comparing a standard versus enhanced implementation strategy to improve outcomes of a mood disorders program.

    PubMed

    Kilbourne, Amy M; Almirall, Daniel; Eisenberg, Daniel; Waxmonsky, Jeanette; Goodrich, David E; Fortney, John C; Kirchner, JoAnn E; Solberg, Leif I; Main, Deborah; Bauer, Mark S; Kyle, Julia; Murphy, Susan A; Nord, Kristina M; Thomas, Marshall R

    2014-09-30

    Despite the availability of psychosocial evidence-based practices (EBPs), treatment and outcomes for persons with mental disorders remain suboptimal. Replicating Effective Programs (REP), an effective implementation strategy, still resulted in less than half of sites using an EBP. The primary aim of this cluster randomized trial is to determine, among sites not initially responding to REP, the effect of adaptive implementation strategies that begin with an External Facilitator (EF) or with an External Facilitator plus an Internal Facilitator (IF) on improved EBP use and patient outcomes in 12 months. This study employs a sequential multiple assignment randomized trial (SMART) design to build an adaptive implementation strategy. The EBP to be implemented is life goals (LG) for patients with mood disorders across 80 community-based outpatient clinics (N = 1,600 patients) from different U.S. regions. Sites not initially responding to REP (defined as < 50% patients receiving ≥ 3 EBP sessions) will be randomized to receive additional support from an EF or both EF/IF. Additionally, sites randomized to EF and still not responsive will be randomized to continue with EF alone or to receive EF/IF. The EF provides technical expertise in adapting LG in routine practice, whereas the on-site IF has direct reporting relationships to site leadership to support LG use in routine practice. The primary outcome is mental health-related quality of life; secondary outcomes include receipt of LG sessions, mood symptoms, implementation costs, and organizational change. This study design will determine whether an off-site EF alone versus the addition of an on-site IF improves EBP uptake and patient outcomes among sites that do not respond initially to REP. It will also examine the value of delaying the provision of EF/IF for sites that continue to not respond despite EF. ClinicalTrials.gov identifier: NCT02151331.

  3. Nurturing Students' Problem-Solving Skills and Engagement in Computer-Mediated Communications (CMC)

    ERIC Educational Resources Information Center

    Chen, Ching-Huei

    2014-01-01

    The present study sought to investigate how to enhance students' well- and ill-structured problem-solving skills and increase productive engagement in computer-mediated communication with the assistance of external prompts, namely procedural and reflection. Thirty-three graduate students were randomly assigned to two conditions: procedural and…

  4. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Giovannetti, Vittorio; Lloyd, Seth; Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139

    The Amosov-Holevo-Werner conjecture implies the additivity of the minimum Renyi entropies at the output of a channel. The conjecture is proven true for all Renyi entropies of integer order greater than two in a class of Gaussian bosonic channel where the input signal is randomly displaced or where it is coupled linearly to an external environment.

  5. Partial Identification of Treatment Effects: Applications to Generalizability

    ERIC Educational Resources Information Center

    Chan, Wendy

    2016-01-01

    Results from large-scale evaluation studies form the foundation of evidence-based policy. The randomized experiment is often considered the gold standard among study designs because the causal impact of a treatment or intervention can be assessed without threats of confounding from external variables. Policy-makers have become increasingly…

  6. Change in Sense of Community: An Empirical Finding

    ERIC Educational Resources Information Center

    Loomis, Colleen; Dockett, Kathleen H.; Brodsky, Anne E.

    2004-01-01

    This study investigated changes in students' psychological sense of community (SOC) under two conditions of external threat against their urban, historically Black, public nonresidential university in a U.S. mid-Atlantic city. Two independent stratified random samples (N = 801 and N = 241) consisting of undergraduate and graduate women (61%) and…

  7. Capturing Students' Attention: An Empirical Study

    ERIC Educational Resources Information Center

    Rosegard, Erik; Wilson, Jackson

    2013-01-01

    College students ("n" = 846) enrolled in a general education course were randomly assigned to either an arousal (experimental) or no-arousal (control) group. The experimental group was exposed to a topic-relevant, 90-second external stimulus (a technique used to elevate arousal and focus attention). The control group listened to the…

  8. Ratings of perceived exertion by women with internal or external locus of control.

    PubMed

    Hassmén, P; Koivula, N

    1996-10-01

    Ratings of perceived exertion are frequently used to estimate the strain and effort experienced subjectively by individuals during various forms of physical activity. A number of factors, both physiological and psychological in origin, have been suggested to work as modifiers of the exertion perceived by the individual. It has been reported in nonsport-related research that individuals with an internal locus of control seem to pay more attention to relevant information and use the available information more adequately than individuals with an external locus of control. The reputed inferior information-processing abilities of externals compared with internals could possibly also influence the ratings of perceived exertion, with externals being less accurate in their ratings. Whether locus of control might be such a factor was investigated. Fifty women worked on an ergometer cycle at four different work loads. The results showed statistically significant differences in subjective ratings of perceived exertion between externals and internals, especially at heavier work loads. Such differences might be because of unequal information-processing abilities, as the observed discrepancies occurred at higher work intensities, when more cues are available for processing.

  9. Financial Stress, Parental Depressive Symptoms, Parenting Practices, and Children's Externalizing Problem Behaviors: Underlying Processes

    ERIC Educational Resources Information Center

    Lee, Chih-Yuan Steven; Lee, Jaerim; August, Gerald J.

    2011-01-01

    This study examined the relationships among financial stress encountered by families, parents' social support, parental depressive symptoms, parenting practices, and children's externalizing problem behaviors to advance our understanding of the processes by which family financial stress is associated with children's problem behaviors. We also…

  10. Development of The Science Processes Test.

    ERIC Educational Resources Information Center

    Ludeman, Robert R.

    Presented is a description and copy of a test manual developed to include items in the test on the basis of children's performance; each item correlated highly with performance on an external criterion. The external criterion was the Individual Competency Measures of the elementary science program Science - A Process Approach (SAPA). The test…

  11. 45 CFR 147.136 - Internal claims and appeals and external review processes.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... RELATING TO HEALTH CARE ACCESS HEALTH INSURANCE REFORM REQUIREMENTS FOR THE GROUP AND INDIVIDUAL HEALTH... external review processes for group health plans and health insurance issuers that are not grandfathered...) In general. A group health plan and a health insurance issuer offering group or individual health...

  12. 45 CFR 147.136 - Internal claims and appeals and external review processes.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... RELATING TO HEALTH CARE ACCESS HEALTH INSURANCE REFORM REQUIREMENTS FOR THE GROUP AND INDIVIDUAL HEALTH... external review processes for group health plans and health insurance issuers that are not grandfathered...) In general. A group health plan and a health insurance issuer offering group or individual health...

  13. 45 CFR 147.136 - Internal claims and appeals and external review processes.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... RELATING TO HEALTH CARE ACCESS HEALTH INSURANCE REFORM REQUIREMENTS FOR THE GROUP AND INDIVIDUAL HEALTH... external review processes for group health plans and health insurance issuers that are not grandfathered...) In general. A group health plan and a health insurance issuer offering group or individual health...

  14. 45 CFR 147.136 - Internal claims and appeals and external review processes.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... RELATING TO HEALTH CARE ACCESS HEALTH INSURANCE REFORM REQUIREMENTS FOR THE GROUP AND INDIVIDUAL HEALTH... external review processes for group health plans and health insurance issuers that are not grandfathered...) In general. A group health plan and a health insurance issuer offering group or individual health...

  15. 45 CFR 147.136 - Internal claims and appeals and external review processes.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... RELATING TO HEALTH CARE ACCESS HEALTH INSURANCE REFORM REQUIREMENTS FOR THE GROUP AND INDIVIDUAL HEALTH... external review processes for group health plans and health insurance issuers that are not grandfathered...) In general. A group health plan and a health insurance issuer offering group or individual health...

  16. Young Children's Social Information Processing: Family Antecedents and Behavioral Correlates

    ERIC Educational Resources Information Center

    Runions, Kevin C.; Keating, Daniel P.

    2007-01-01

    Little research has examined whether social information processing (SIP) measures from early childhood predict externalizing problems beyond the shared association with familial risk markers. In the present study, family antecedents and first-grade externalizing behaviors were studied in relation to preschool and 1st-grade SIP using data from…

  17. Impact of Therapist Self-Disclosure.

    ERIC Educational Resources Information Center

    O'Hare, Christopher

    The effects of first-session interviewer self-disclosures that differed in three levels of intimacy--low, medium and high--and three kinds of temporal focus--historical (past tense and external to the interview process), current (present tense and external to the interview process), and existential in which the interviewer disclosed immediate…

  18. Open reduction and internal fixation compared to closed reduction and external fixation in distal radial fractures

    PubMed Central

    Kopylov, Philippe; Geijer, Mats; Tägil, Magnus

    2009-01-01

    Background and purpose In unstable distal radial fractures that are impossible to reduce or to maintain in reduced position, the treatment of choice is operation. The type of operation and the choice of implant, however, is a matter of discussion. Our aim was to investigate whether open reduction and internal fixation would produce a better result than traditional external fixation. Methods 50 patients with an unstable or comminute distal radius fracture were randomized to either closed reduction and bridging external fixation, or open reduction and internal fixation using the TriMed system. The primary outcome parameter was grip strength, but the patients were followed for 1 year with objective clinical assessment, subjective outcome using DASH, and radiographic examination. Results At 1 year postoperatively, grip strength was 90% (SD 16) of the uninjured side in the internal fixation group and 78% (17) in the external fixation group. Pronation/supination was 150° (15) in the internal fixation group and 136° (20) in the external fixation group at 1 year. There were no differences in DASH scores or in radiographic parameters. 5 patients in the external fixation group were reoperated due to malunion, as compared to 1 in the internal fixation group. 7 other cases were classified as radiographic malunion: 5 in the external fixation group and 2 in the internal fixation group. Interpretation Internal fixation gave better grip strength and a better range of motion at 1 year, and tended to have less malunions than external fixation. No difference could be found regarding subjective outcome. PMID:19857180

  19. Siting a municipal solid waste disposal facility, part II: the effects of external criteria on the final decision.

    PubMed

    Korucu, M Kemal; Karademir, Aykan

    2014-02-01

    The procedure of a multi-criteria decision analysis supported by the geographic information systems was applied to the site selection process of a planning municipal solid waste management practice based on twelve different scenarios. The scenarios included two different decision tree modes and two different weighting models for three different area requirements. The suitability rankings of the suitable sites obtained from the application of the decision procedure for the scenarios were assessed by a factorial experimental design concerning the effect of some external criteria on the final decision of the site selection process. The external criteria used in the factorial experimental design were defined as "Risk perception and approval of stakeholders" and "Visibility". The effects of the presence of these criteria in the decision trees were evaluated in detail. For a quantitative expression of the differentiations observed in the suitability rankings, the ranking data were subjected to ANOVA test after a normalization process. Then the results of these tests were evaluated by Tukey test to measure the effects of external criteria on the final decision. The results of Tukey tests indicated that the involvement of the external criteria into the decision trees produced statistically meaningful differentiations in the suitability rankings. Since the external criteria could cause considerable external costs during the operation of the disposal facilities, the presence of these criteria in the decision tree in addition to the other criteria related to environmental and legislative requisites could prevent subsequent external costs in the first place.

  20. The Risks to Patient Privacy from Publishing Data from Clinical Anesthesia Studies.

    PubMed

    O'Neill, Liam; Dexter, Franklin; Zhang, Nan

    2016-06-01

    In this article, we consider the privacy implications of posting data from small, randomized trials, observational studies, or case series in anesthesia from a few (e.g., 1-3) hospitals. Prior to publishing such data as supplemental digital content, the authors remove attributes that could be used to re-identify individuals, a process known as "anonymization." Posting health information that has been properly "de-identified" is assumed to pose no risks to patient privacy. Yet, computer scientists have demonstrated that this assumption is flawed. We consider various realistic scenarios of how the publication of such data could lead to breaches of patient privacy. Several examples of successful privacy attacks are reviewed, as well as the methods used. We survey the latest models and methods from computer science for protecting health information and their application to posting data from small anesthesia studies. To illustrate the vulnerability of such published data, we calculate the "population uniqueness" for patients undergoing one or more surgical procedures using data from the State of Texas. For a patient selected uniformly at random, the probability that an adversary could match this patient's record to a unique record in the state external database was 42.8% (SE < 0.1%). Despite the 42.8% being an unacceptably high level of risk, it underestimates the risk for patients from smaller states or provinces. We propose an editorial policy that greatly reduces the likelihood of a privacy breach, while supporting the goal of transparency of the research process.

  1. Effects of a Brief Psychoeducational Intervention for Family Conflict: Constructive Conflict, Emotional Insecurity and Child Adjustment.

    PubMed

    Miller-Graff, Laura E; Cummings, E Mark; Bergman, Kathleen N

    2016-10-01

    The role of emotional security in promoting positive adjustment following exposure to marital conflict has been identified in a large number of empirical investigations, yet to date, no interventions have explicitly addressed the processes that predict child adjustment after marital conflict. The current study evaluated a randomized controlled trial of a family intervention program aimed at promoting constructive marital conflict behaviors thereby increasing adolescent emotional security and adjustment. Families (n = 225) were randomized into 1 of 4 conditions: Parent-Adolescent (n = 75), Parent-Only (n = 75), Self-Study (n = 38) and No Treatment (n = 37). Multi-informant and multi-method assessments were conducted at baseline, post-treatment and 6-month follow-up. Effects of treatment on destructive and constructive conflict behaviors were evaluated using multilevel models where observations were nested within individuals over time. Process models assessing the impact of constructive and destructive conflict behaviors on emotional insecurity and adolescent adjustment were evaluated using path modeling. Results indicated that the treatment was effective in increasing constructive conflict behaviors (d = 0.89) and decreasing destructive conflict behaviors (d = -0.30). For the Parent-Only Group, post-test constructive conflict behaviors directly predicted lower levels of adolescent externalizing behaviors at 6-month follow-up. Post-test constructive conflict skills also indirectly affected adolescent internalizing behaviors through adolescent emotional security. These findings support the use of a brief psychoeducational intervention in improving post-treatment conflict and emotional security about interparental relationships.

  2. [Complications of open reduction and internal fixation versus external fixation for unstable distal radius fractures: a meta-analysis].

    PubMed

    Yang, Z; Yuan, Z Z; Ma, J X; Ma, X L

    2016-12-20

    Objective: To make a systematic assessment of the complications of open reduction and internal fixation versus external fixation for unstable distal radius fractures. Method: A computer-based online search of PubMed, ScienceDirect, EMBASE, BIOSIS, Springer and Cochrane Library were performed.The randomized and controlled trials of open reduction and internal fixation versus external fixation for unstable distal radius fractures were collected.The included trials were screened out strictly based on the criterion of inclusion and exclusion.The quality of included trials was evaluated.RevMan 5.0 was used for data analysis. Result: A total of 17 studies involving 1 402 patients were included.There were 687 patients with open reduction and internal fixation and 715 with external fixation.The results of Meta-analysis indicated that there were statistically significant differences with regard to the postoperatively total complications, infection, malunion, tendon rupture ( I 2 =8%, RR =0.77(95% CI 0.65-0.91, Z =3.10, P <0.05). There were no statistically significant differences observed between two approaches with respect to nounion, re-operation, complex regional pain syndrome, carpal tunnel syndrome, neurapraxia, tendonitis, painful hardware, scar( P >0.05). Conclusion: Postoperative complications are present in both open reduction and internal fixation and external fixation.Compared with external fixation, open reduction and internal fixation is lower in total complications postoperatively, infection and malunion, but external fixation has lower tendon rupture incidence.

  3. Propagation of Data Dependency through Distributed Cooperating Processes

    DTIC Science & Technology

    1988-09-01

    12 The External Data Dependency Analyzer ( EDDA ) .................................................. 12 The new EPL...47 EDDA Patch Files for the Dining Philosophers Example [Figure 23] ................... 49 L im itations...dependencies is evident. The External Data Dependency Analyzer ( EDDA ) The EDDA derives external data dependencies by performing two levels of analysis

  4. [Does Emotional Context Affect Subliminal and Supraliminal Priming?].

    PubMed

    Baran, Zeynel; Cangöz, Banu; Salman, Funda

    2016-01-01

    Emotions are complex psychophysiological changes experienced during the interactions of internal and external processes. The stimuli that have emotional value have processing efficiency both in encoding and retrieval processes with respect to the neutral stimuli. Processing advantage is present also for implicit memory. Priming effect does not require conscious recollection and leads to changes in responding due to previous exposure to the stimulus. In this study, it was aimed to investigate the effect of presentation type and different emotional contexts on the priming. Sixty-volunteered-university-students were (Female: n=40, X age=19.03±1.23; Male: n=20, X age=19.70±1.92) randomly assigned to the experimental conditions. Presentation type (Subliminal and Supraliminal) was between subject and Emotional Context (pleasant, neutral, and unpleasant pictures) was within subject independent variables. Dependent variables were Word Stem Completion score and completion latencies. Unpleasant emotional context had more capacity to create priming effect than the other emotional contexts. Both Subliminal and Supraliminal conditions favored the priming. Controversially to the transfer appropriate processing approach, the priming effect that was produced by supraliminal condition significantly higher than the priming created by the subliminal condition. Unpleasant picture context produced more priming due to reason that evolutionarily important, i.e. thread-related, stimuli have processing priority and they capture the attention, utilize other cognitive resources easily. Even in priming, that is a phenomenon based heavily on data driven processes, concept driven processes are also effectual as indicated by levels-of-processing approach.

  5. The External Quality Assessment Scheme (EQAS): Experiences of a medium sized accredited laboratory.

    PubMed

    Bhat, Vivek; Chavan, Preeti; Naresh, Chital; Poladia, Pratik

    2015-06-15

    We put forth our experiences of EQAS, analyzed the result discrepancies, reviewed the corrective actions and also put forth strategies for risk identification and prevention of potential errors in a medical laboratory. For hematology, EQAS samples - blood, peripheral and reticulocyte smears - were received quarterly every year. All the blood samples were processed on HMX hematology analyzer by Beckman-Coulter. For clinical chemistry, lyophilized samples were received and were processed on Siemens Dimension Xpand and RXL analyzers. For microbiology, EQAS samples were received quarterly every year as lyophilized strains along with smears and serological samples. In hematology no outliers were noted for reticulocyte and peripheral smear examination. Only one outlier was noted for CBC. In clinical chemistry outliers (SDI ≥ 2) were noted in 7 samples (23 parameters) out of total 36 samples (756 parameters) processed. Thirteen of these parameters were analyzed as random errors, 3 as transcriptional errors and seven instances of systemic error were noted. In microbiology, one discrepancy was noted in isolate identification and in the grading of smears for AFB by Ziehl Neelsen stain. EQAS along with IQC is a very important tool for maintaining optimal quality of services. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Results of the Baikal Experiment on Observations of Macroscopic Nonlocal Correlations in Reverse Time

    NASA Astrophysics Data System (ADS)

    Korotaev, S. M.; Serdyuk, V. O.; Kiktenko, E. O.; Budnev, N. M.; Gorohov, J. V.

    Although the general theory macroscopic quantum entanglement of is still in its infancy, consideration of the matter in the framework of action-at-a distance electrodynamics predicts for the random dissipative processes observability of the advanced nonlocal correlations (time reversal causality). These correlations were really revealed in our previous experiments with some large-scale heliogeophysical processes as the source ones and the lab detectors as the probe ones. Recently a new experiment has been performing on the base of Baikal Deep Water Neutrino Observatory. The thick water layer is an excellent shield against any local impacts on the detectors. The first annual series 2012/2013 has demonstrated that detector signals respond to the heliogeophysical (external) processes and causal connection of the signals directed downwards: from the Earth surface to the Baikal floor. But this nonlocal connection proved to be in reverse time. In addition advanced nonlocal correlation of the detector signal with the regional source-process: the random component of hydrological activity in the upper layer was revealed and the possibility of its forecast on nonlocal correlations was demonstrated. But the strongest macroscopic nonlocal correlations are observed at extremely low frequencies, that is at periods of several months. Therefore the above results should be verified in a longer experiment. We verify them by data of the second annual series 2013/2014 of the Baikal experiment. All the results have been confirmed, although some quantitative parameters of correlations and time reversal causal links turned out different due to nonstationarity of the source-processes. A new result is displaying of the advanced response of nonlocal correlation detector to the earthquake. This opens up the prospect of the earthquake forecast on the new physical principle, although further confirmation in the next events is certainly needed. The continuation of the Baikal experiment with expanded program is burning.

  7. Does prism width from the shell prismatic layer have a random distribution?

    NASA Astrophysics Data System (ADS)

    Vancolen, Séverine; Verrecchia, Eric

    2008-10-01

    A study of the distribution of the prism width inside the prismatic layer of Unio tumidus (Philipsson 1788, Diss Hist-Nat, Berling, Lundæ) from Lake Neuchâtel, Switzerland, has been conducted in order to determine whether or not this distribution is random. Measurements of 954 to 1,343 prism widths (depending on shell sample) have been made using a scanning electron microscope in backscattered electron mode. A white noise test has been applied to the distribution of prism sizes (i.e. width). It shows that there is no temporal cycle that could potentially influence their formation and growth. These results suggest that prism widths are randomly distributed, and related neither to external rings nor to environmental constraints.

  8. Intelligent process development of foam molding for the Thermal Protection System (TPS) of the space shuttle external tank

    NASA Technical Reports Server (NTRS)

    Bharwani, S. S.; Walls, J. T.; Jackson, M. E.

    1987-01-01

    A knowledge based system to assist process engineers in evaluating the processability and moldability of poly-isocyanurate (PIR) formulations for the thermal protection system of the Space Shuttle external tank (ET) is discussed. The Reaction Injection Molding- Process Development Advisor (RIM-PDA) is a coupled system which takes advantage of both symbolic and numeric processing techniques. This system will aid the process engineer in identifying a startup set of mold schedules and in refining the mold schedules to remedy specific process problems diagnosed by the system.

  9. Memory effects for a stochastic fractional oscillator in a magnetic field

    NASA Astrophysics Data System (ADS)

    Mankin, Romi; Laas, Katrin; Laas, Tõnu; Paekivi, Sander

    2018-01-01

    The problem of random motion of harmonically trapped charged particles in a constant external magnetic field is studied. A generalized three-dimensional Langevin equation with a power-law memory kernel is used to model the interaction of Brownian particles with the complex structure of viscoelastic media (e.g., dusty plasmas). The influence of a fluctuating environment is modeled by an additive fractional Gaussian noise. In the long-time limit the exact expressions of the first-order and second-order moments of the fluctuating position for the Brownian particle subjected to an external periodic force in the plane perpendicular to the magnetic field have been calculated. Also, the particle's angular momentum is found. It is shown that an interplay of external periodic forcing, memory, and colored noise can generate a variety of cooperation effects, such as memory-induced sign reversals of the angular momentum, multiresonance versus Larmor frequency, and memory-induced particle confinement in the absence of an external trapping field. Particularly in the case without external trapping, if the memory exponent is lower than a critical value, we find a resonancelike behavior of the anisotropy in the particle position distribution versus the driving frequency, implying that it can be efficiently excited by an oscillating electric field. Similarities and differences between the behaviors of the models with internal and external noises are also discussed.

  10. The Process of Probability Problem Solving: Use of External Visual Representations

    ERIC Educational Resources Information Center

    Zahner, Doris; Corter, James E.

    2010-01-01

    We investigate the role of external inscriptions, particularly those of a spatial or visual nature, in the solution of probability word problems. We define a taxonomy of external visual representations used in probability problem solving that includes "pictures," "spatial reorganization of the given information," "outcome listings," "contingency…

  11. Sex Differences in the Longitudinal Relations among Family Risk Factors and Childhood Externalizing Symptoms

    ERIC Educational Resources Information Center

    Blatt-Eisengart, Ilana; Drabick, Deborah A. G.; Monahan, Kathryn C.; Steinberg, Laurence

    2009-01-01

    Despite potential sex differences in base rates, predictors, and maintaining processes for children's externalizing behaviors, little prospective research has examined sex differences in the relations between concurrent, proximal family risk factors and children's externalizing behaviors. The current study examined the relations among maternal…

  12. The Perils of Ignoring Design Effects in Experimental Studies: Lessons from a Mammography Screening Trial

    PubMed Central

    Glenn, Beth A.; Bastani, Roshan; Maxwell, Annette E.

    2013-01-01

    Objective Threats to external validity including pretest sensitization and the interaction of selection and an intervention are frequently overlooked by researchers despite their potential to significantly influence study outcomes. The purpose of this investigation was to conduct secondary data analyses to assess the presence of external validity threats in the setting of a randomized trial designed to promote mammography use in a high risk sample of women. Design During the trial, recruitment and intervention implementation took place in three cohorts (with different ethnic composition), utilizing two different designs (pretest-posttest control group design; posttest only control group design). Results Results reveal that the intervention produced different outcomes across cohorts, dependent upon the research design used and the characteristics of the sample. Conclusion These results illustrate the importance of weighing the pros and cons of potential research designs before making a selection and attending more closely to issues of external validity. PMID:23289517

  13. Radiation-related quality of life parameters after targeted intraoperative radiotherapy versus whole breast radiotherapy in patients with breast cancer: results from the randomized phase III trial TARGIT-A.

    PubMed

    Welzel, Grit; Boch, Angela; Sperk, Elena; Hofmann, Frank; Kraus-Tiefenbacher, Uta; Gerhardt, Axel; Suetterlin, Marc; Wenz, Frederik

    2013-01-07

    Intraoperative radiotherapy (IORT) is a new treatment approach for early stage breast cancer. This study reports on the effects of IORT on radiation-related quality of life (QoL) parameters. Two hundred and thirty women with stage I-III breast cancer (age, 31 to 84 years) were entered into the study. A single-center subgroup of 87 women from the two arms of the randomized phase III trial TARGIT-A (TARGeted Intra-operative radioTherapy versus whole breast radiotherapy for breast cancer) was analyzed. Furthermore, results were compared to non-randomized control groups: n = 90 receiving IORT as a tumor bed boost followed by external beam whole breast radiotherapy (EBRT) outside of TARGIT-A (IORT-boost), and n = 53 treated with EBRT followed by an external-beam boost (EBRT-boost). QoL was collected using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaires C30 (QLQ-C30) and BR23 (QLQ-BR23). The mean follow-up period in the TARGIT-A groups was 32 versus 39 months in the non-randomized control groups. Patients receiving IORT alone reported less general pain (21.3 points), breast (7.0 points) and arm (15.1 points) symptoms, and better role functioning (78.7 points) as patients receiving EBRT (40.9; 19.0; 32.8; and 60.5 points, respectively, P < 0.01). Patients receiving IORT alone also had fewer breast symptoms than TARGIT-A patients receiving IORT followed by EBRT for high risk features on final pathology (IORT-EBRT; 7.0 versus 29.7 points, P < 0.01). There were no significant differences between TARGIT-A patients receiving IORT-EBRT compared to non-randomized IORT-boost or EBRT-boost patients and patients receiving EBRT without a boost. In the randomized setting, important radiation-related QoL parameters after IORT were superior to EBRT. Non-randomized comparisons showed equivalent parameters in the IORT-EBRT group and the control groups.

  14. FPGA Sequencer for Radar Altimeter Applications

    NASA Technical Reports Server (NTRS)

    Berkun, Andrew C.; Pollard, Brian D.; Chen, Curtis W.

    2011-01-01

    A sequencer for a radar altimeter provides accurate attitude information for a reliable soft landing of the Mars Science Laboratory (MSL). This is a field-programmable- gate-array (FPGA)-only implementation. A table loaded externally into the FPGA controls timing, processing, and decision structures. Radar is memory-less and does not use previous acquisitions to assist in the current acquisition. All cycles complete in exactly 50 milliseconds, regardless of range or whether a target was found. A RAM (random access memory) within the FPGA holds instructions for up to 15 sets. For each set, timing is run, echoes are processed, and a comparison is made. If a target is seen, more detailed processing is run on that set. If no target is seen, the next set is tried. When all sets have been run, the FPGA terminates and waits for the next 50-millisecond event. This setup simplifies testing and improves reliability. A single vertex chip does the work of an entire assembly. Output products require minor processing to become range and velocity. This technology is the heart of the Terminal Descent Sensor, which is an integral part of the Entry Decent and Landing system for MSL. In addition, it is a strong candidate for manned landings on Mars or the Moon.

  15. Bistability and up/down state alternations in inhibition-dominated randomly connected networks of LIF neurons.

    PubMed

    Tartaglia, Elisa M; Brunel, Nicolas

    2017-09-20

    Electrophysiological recordings in cortex in vivo have revealed a rich variety of dynamical regimes ranging from irregular asynchronous states to a diversity of synchronized states, depending on species, anesthesia, and external stimulation. The average population firing rate in these states is typically low. We study analytically and numerically a network of sparsely connected excitatory and inhibitory integrate-and-fire neurons in the inhibition-dominated, low firing rate regime. For sufficiently high values of the external input, the network exhibits an asynchronous low firing frequency state (L). Depending on synaptic time constants, we show that two scenarios may occur when external inputs are decreased: (1) the L state can destabilize through a Hopf bifucation as the external input is decreased, leading to synchronized oscillations spanning d δ to β frequencies; (2) the network can reach a bistable region, between the low firing frequency network state (L) and a quiescent one (Q). Adding an adaptation current to excitatory neurons leads to spontaneous alternations between L and Q states, similar to experimental observations on UP and DOWN states alternations.

  16. Tuning in to teens: Improving parental responses to anger and reducing youth externalizing behavior problems.

    PubMed

    Havighurst, Sophie S; Kehoe, Christiane E; Harley, Ann E

    2015-07-01

    Parent emotion socialization plays an important role in shaping emotional and behavioral development during adolescence. The Tuning in to Teens (TINT) program aims to improve parents' responses to young people's emotions with a focus on teaching emotion coaching. This study examined the efficacy of the TINT program in improving emotion socialization practices in parents and whether this reduced family conflict and youth externalizing difficulties. Schools were randomized into intervention and control conditions and 225 primary caregiving parents and 224 youth took part in the study. Self-report data was collected from parents and youth during the young person's final year of elementary school and again in their first year of secondary school. Multilevel analyses showed significant improvements in parent's impulse control difficulties and emotion socialization, as well as significant reductions in family conflict and youth externalizing difficulties. This study provides support for the TINT program in reducing youth externalizing behavior problems. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  17. Can Parenting Intervention Prevent Cascading Effects From Placement Instability to Insecure Attachment to Externalizing Problems in Maltreated Toddlers?

    PubMed

    Pasalich, Dave S; Fleming, Charles B; Oxford, Monica L; Zheng, Yao; Spieker, Susan J

    2016-08-01

    Multiple placement changes disrupt continuity in caregiving and undermine well-being in children in child welfare. This study conducted secondary data analysis of a randomized controlled trial to examine whether a relationship-based intervention, Promoting First Relationships(©) (PFR), reduced risk for a maladaptive cascade from placement instability to less secure attachment to elevated externalizing problems. Participants included caregivers (birth or foster/kin) of toddlers (10-24 months) recently transitioned to their care because of child welfare placement decisions. Although main effects of PFR on security and externalizing problems were not previously observed, this study's results revealed that PFR attenuated the association between multiple placement changes (baseline) and less security (postintervention) and that the indirect effect of placement instability on greater externalizing problems (6-month follow-up) via less security was evident only in toddlers in the comparison condition. These findings shed light on how a history of multiple caregiver changes may influence toddlers' risk for poor adjustment in subsequent placements, and the promise of supporting caregivers through a parenting intervention to prevent such risk. © The Author(s) 2016.

  18. Can parenting intervention prevent cascading effects from placement instability to insecure attachment to externalizing problems in maltreated toddlers?

    PubMed Central

    Pasalich, Dave S.; Fleming, Charles B.; Oxford, Monica L.; Zheng, Yao; Spieker, Susan J.

    2016-01-01

    Multiple placement changes disrupt continuity in caregiving and undermine well-being in children in child welfare. This study conducted secondary data analysis of a randomized controlled trial to examine whether a relationship-based intervention, Promoting First Relationships© (PFR), reduced risk for a maladaptive cascade from placement instability to less secure attachment to elevated externalizing problems. Participants included caregivers (birth or foster/kin) of toddlers (10–24 months) recently transitioned to their care because of child welfare placement decisions. Although main effects of PFR on security and externalizing problems were not previously observed, this study’s results revealed that PFR attenuated the association between multiple placement changes (baseline) and less security (postintervention), and that the indirect effect of placement instability on greater externalizing problems (6-month follow-up) via less security was evident only in toddlers in the comparison condition. These findings shed light on how a history of multiple caregiver changes may influence toddlers’ risk for poor adjustment in subsequent placements, and the promise of supporting caregivers through a parenting intervention to prevent such risk. PMID:27381935

  19. Interactive effects of the affect quality and directional focus of mental imagery on pain analgesia.

    PubMed

    Alden, A L; Dale, J A; DeGood, D E

    2001-06-01

    College students (25 men and 25 women) were randomly assigned (within sex) to each of the 4 factorial groups, based on manipulation of affect quality (positive vs. negative) and directional focus (internal vs. external) of mental imagery, and to a control group receiving no manipulation. Both imagery variables had a significant impact on pain tolerance and ratings during a cold-pressor test with positive affect and external imagery producing greater analgesia than their counterpart conditions. Positive affect imagery combined with external imagery resulted in the lowest reported pain amongst the groups. However, self-reported mood descriptors did not consistently parallel the pain tolerance and rating data. Likewise, although heart rate and skin potential responses increased during the cold pressor for the group as a whole, the only significant difference amongst the experimental groups was the relatively higher skin potential reactivity of the positive affect-external imagery group--possibly reflecting greater task engagement for this group. Seemingly, imagery in this situation operates primarily via cognitive, rather than via physiological mediators of the pain experience.

  20. Family and Child Characteristics Linking Neighborhood Context and Child Externalizing Behavior

    ERIC Educational Resources Information Center

    Roosa, Mark W.; Deng, Shiying; Ryu, Ehri; Lockhart Burrell, Ginger; Tein, Jenn-Yun; Jones, Sarah; Lopez, Vera; Crowder, Sakina

    2005-01-01

    Neighborhood conditions are related to children's externalizing behavior, although few processes that help explain this association have been identified. With data from 189 primarily low-income Anglo and Mexican American families, we tested a stress process model that included 3 potential mediators of this relationship. The results showed that…

  1. 29 CFR 2590.715-2719 - Internal claims and appeals and external review processes.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... SECURITY ADMINISTRATION, DEPARTMENT OF LABOR GROUP HEALTH PLANS RULES AND REGULATIONS FOR GROUP HEALTH... and appeals and external review processes for group health plans and health insurance issuers that are..., 2010. (b) Internal claims and appeals process—(1) In general. A group health plan and a health...

  2. 26 CFR 54.9815-2719T - Internal claims and appeals and external review processes (temporary).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... external review processes for group health plans and health insurance issuers that are not grandfathered...) In general. A group health plan and a health insurance issuer offering group health insurance...). (2) Requirements for group health plans and group health insurance issuers. A group health plan and a...

  3. 26 CFR 54.9815-2719T - Internal claims and appeals and external review processes (temporary).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... external review processes for group health plans and health insurance issuers that are not grandfathered...) In general. A group health plan and a health insurance issuer offering group health insurance...). (2) Requirements for group health plans and group health insurance issuers. A group health plan and a...

  4. 29 CFR 2590.715-2719 - Internal claims and appeals and external review processes.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... SECURITY ADMINISTRATION, DEPARTMENT OF LABOR GROUP HEALTH PLANS RULES AND REGULATIONS FOR GROUP HEALTH... and appeals and external review processes for group health plans and health insurance issuers that are..., 2010. (b) Internal claims and appeals process—(1) In general. A group health plan and a health...

  5. 26 CFR 54.9815-2719T - Internal claims and appeals and external review processes (temporary).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... external review processes for group health plans and health insurance issuers that are not grandfathered...) In general. A group health plan and a health insurance issuer offering group health insurance...). (2) Requirements for group health plans and group health insurance issuers. A group health plan and a...

  6. 26 CFR 54.9815-2719T - Internal claims and appeals and external review processes (temporary).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... external review processes for group health plans and health insurance issuers that are not grandfathered...) In general. A group health plan and a health insurance issuer offering group health insurance...). (2) Requirements for group health plans and group health insurance issuers. A group health plan and a...

  7. 29 CFR 2590.715-2719 - Internal claims and appeals and external review processes.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... SECURITY ADMINISTRATION, DEPARTMENT OF LABOR GROUP HEALTH PLANS RULES AND REGULATIONS FOR GROUP HEALTH... and appeals and external review processes for group health plans and health insurance issuers that are..., 2010. (b) Internal claims and appeals process—(1) In general. A group health plan and a health...

  8. Reputation and Image: Some Connections to Resource Environments

    ERIC Educational Resources Information Center

    Hoagland, Steven R.

    2012-01-01

    The purpose of this paper is to extend knowledge about the external environment in which educational organizations operate and the patterns by which their resource flows translate into sources of uncertainty. Methods include examination of cross sectional and longitudinal data from secondary sources and a survey on a random sample of 80 public…

  9. Adapting Parent-Child Interaction Therapy to Foster Care

    ERIC Educational Resources Information Center

    Mersky, Joshua P.; Topitzes, James; Grant-Savela, Stacey D.; Brondino, Michael J.; McNeil, Cheryl B.

    2016-01-01

    Objective: This study presents outcomes from a randomized trial of a novel Parent-Child Interaction Therapy (PCIT) model for foster families. Differential effects of two intervention doses on child externalizing and internalizing symptoms are examined. Method: A sample of 102 foster children was assigned to one of three conditions--brief PCIT,…

  10. Preventing Adolescents' Externalizing and Internalizing Symptoms: Effects of the Penn Resiliency Program

    ERIC Educational Resources Information Center

    Cutuli, J. J.; Gillham, Jane E.; Chaplin, Tara M.; Reivich, Karen J.; Seligman, Martin E. P.; Gallop, Robert J.; Abenavoli, Rachel M.; Freres, Derek R.

    2013-01-01

    This study reports secondary outcome analyses from a past study of the Penn Resiliency Program (PRP), a cognitive-behavioral depression prevention program for middle-school aged children. Middle school students (N = 697) were randomly assigned to PRP, PEP (an alternate intervention), or control conditions. Gillham et al., (2007) reported analyses…

  11. The Girlfriends Project: Evaluating a Promising Community-Based Intervention from a Bottom-Up Perspective

    ERIC Educational Resources Information Center

    Hawk, Mary

    2015-01-01

    Randomized controlled trials are the gold standard in research but may not fully explain or predict outcome variations in community-based interventions. Demonstrating efficacy of externally driven programs in well-controlled environments may not translate to community-based implementation where resources and priorities vary. A bottom-up evaluation…

  12. Validation of Geriatric Depression Scale--5 Scores among Sedentary Older Adults

    ERIC Educational Resources Information Center

    Marquez, David X.; McAuley, Edward; Motl, Robert W.; Elavsky, Steriani; Konopack, James F.; Jerome, Gerald J.; Kramer, Arthur F.

    2006-01-01

    This study examined the validity of Geriatric Depression Scale--5 (GDS-5) scores among older sedentary adults based on its structural properties and relationship with external criteria. Participants from two samples (Ns = 185 and 93; M ages = 66 and 67 years) completed baseline assessments as part of randomized controlled exercise trials.…

  13. Hysteresis-induced bifurcation and chaos in a magneto-rheological suspension system under external excitation

    NASA Astrophysics Data System (ADS)

    Hailong, Zhang; Enrong, Wang; Fuhong, Min; Ning, Zhang

    2016-03-01

    The magneto-rheological damper (MRD) is a promising device used in vehicle semi-active suspension systems, for its continuous adjustable damping output. However, the innate nonlinear hysteresis characteristic of MRD may cause the nonlinear behaviors. In this work, a two-degree-of-freedom (2-DOF) MR suspension system was established first, by employing the modified Bouc-Wen force-velocity (F-v) hysteretic model. The nonlinear dynamic response of the system was investigated under the external excitation of single-frequency harmonic and bandwidth-limited stochastic road surface. The largest Lyapunov exponent (LLE) was used to detect the chaotic area of the frequency and amplitude of harmonic excitation, and the bifurcation diagrams, time histories, phase portraits, and power spectrum density (PSD) diagrams were used to reveal the dynamic evolution process in detail. Moreover, the LLE and Kolmogorov entropy (K entropy) were used to identify whether the system response was random or chaotic under stochastic road surface. The results demonstrated that the complex dynamical behaviors occur under different external excitation conditions. The oscillating mechanism of alternating periodic oscillations, quasi-periodic oscillations, and chaotic oscillations was observed in detail. The chaotic regions revealed that chaotic motions may appear in conditions of mid-low frequency and large amplitude, as well as small amplitude and all frequency. The obtained parameter regions where the chaotic motions may appear are useful for design of structural parameters of the vibration isolation, and the optimization of control strategy for MR suspension system. Projects supported by the National Natural Science Foundation of China (Grant Nos. 51475246, 51277098, and 51075215), the Research Innovation Program for College Graduates of Jiangsu Province China (Grant No. KYLX15 0725), and the Natural Science Foundation of Jiangsu Province of China (Grant No. BK20131402).

  14. Modern modeling techniques had limited external validity in predicting mortality from traumatic brain injury.

    PubMed

    van der Ploeg, Tjeerd; Nieboer, Daan; Steyerberg, Ewout W

    2016-10-01

    Prediction of medical outcomes may potentially benefit from using modern statistical modeling techniques. We aimed to externally validate modeling strategies for prediction of 6-month mortality of patients suffering from traumatic brain injury (TBI) with predictor sets of increasing complexity. We analyzed individual patient data from 15 different studies including 11,026 TBI patients. We consecutively considered a core set of predictors (age, motor score, and pupillary reactivity), an extended set with computed tomography scan characteristics, and a further extension with two laboratory measurements (glucose and hemoglobin). With each of these sets, we predicted 6-month mortality using default settings with five statistical modeling techniques: logistic regression (LR), classification and regression trees, random forests (RFs), support vector machines (SVM) and neural nets. For external validation, a model developed on one of the 15 data sets was applied to each of the 14 remaining sets. This process was repeated 15 times for a total of 630 validations. The area under the receiver operating characteristic curve (AUC) was used to assess the discriminative ability of the models. For the most complex predictor set, the LR models performed best (median validated AUC value, 0.757), followed by RF and support vector machine models (median validated AUC value, 0.735 and 0.732, respectively). With each predictor set, the classification and regression trees models showed poor performance (median validated AUC value, <0.7). The variability in performance across the studies was smallest for the RF- and LR-based models (inter quartile range for validated AUC values from 0.07 to 0.10). In the area of predicting mortality from TBI, nonlinear and nonadditive effects are not pronounced enough to make modern prediction methods beneficial. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Electrostatic energy harvesting device with dual resonant structure for wideband random vibration sources at low frequency.

    PubMed

    Zhang, Yulong; Wang, Tianyang; Zhang, Ai; Peng, Zhuoteng; Luo, Dan; Chen, Rui; Wang, Fei

    2016-12-01

    In this paper, we present design and test of a broadband electrostatic energy harvester with a dual resonant structure, which consists of two cantilever-mass subsystems each with a mass attached at the free edge of a cantilever. Comparing to traditional devices with single resonant frequency, the proposed device with dual resonant structure can resonate at two frequencies. Furthermore, when one of the cantilever-masses is oscillating at resonance, the vibration amplitude is large enough to make it collide with the other mass, which provides strong mechanical coupling between the two subsystems. Therefore, this device can harvest a decent power output from vibration sources at a broad frequency range. During the measurement, continuous power output up to 6.2-9.8 μW can be achieved under external vibration amplitude of 9.3 m/s 2 at a frequency range from 36.3 Hz to 48.3 Hz, which means the bandwidth of the device is about 30% of the central frequency. The broad bandwidth of the device provides a promising application for energy harvesting from the scenarios with random vibration sources. The experimental results indicate that with the dual resonant structure, the vibration-to-electricity energy conversion efficiency can be improved by 97% when an external random vibration with a low frequency filter is applied.

  16. Effects of vibration and shock on the performance of gas-bearing space-power Brayton cycle turbomachinery. Part 4: Suppression of rotor-bearing system vibrations through flexible bearing support damping

    NASA Technical Reports Server (NTRS)

    Tessarzik, J. M.; Chiang, T.; Badgley, R. H.

    1974-01-01

    A bearing damper, operating on the support flexure of a pivoted pad in a tilting-pad type gas-lubricated journal bearing, has been designed, built, and tested under externally-applied random vibrations. The NASA Brayton Rotating Unit (BRU), a 36,000 rpm, 10-Kwe turbogenerator had previously been subjected in the MTI Vibration Test Laboratory to external random vibrations, and vibration response data had been recorded and analyzed for amplitude distribution and frequency content at a number of locations in the machine. Based on data from that evaluation, a piston-type damper was designed and developed for each of the two flexibly-supported journal bearing pads (one in each of the two three-pad bearings). A modified BRU, with dampers installed, has been re-tested under random vibration conditions. Root-mean-square vibration amplitudes were determined from the test data, and displacement power spectral density analyses have been performed. Results of these data reduction efforts have been compared with vibration tolerance limits. Results of the tests indicate significant reductions in vibration levels in the bearing gas-lubricant films, particularly in the rigidly-mounted pads. The utility of the gas-lubricated damper for limiting rotor-bearing system vibrations in high-speed turbomachinery has thus been demonstrated.

  17. Randomized controlled trial on postoperative pulmonary humidification after total laryngectomy: external humidifier versus heat and moisture exchanger.

    PubMed

    Mérol, Jean-Claude; Charpiot, Anne; Langagne, Thibault; Hémar, Patrick; Ackerstaff, Annemieke H; Hilgers, Frans J M

    2012-02-01

    Assessment of immediate postoperative airway humidification after total laryngectomy (TLE), comparing the use of an external humidifier (EH) with humidification through a heat and moisture exchanger (HME). Randomized controlled trial (RCT). Fifty-three patients were randomized into the standard (control) EH (N = 26) or the experimental HME arm (N = 27). Compliance, pulmonary and sleeping problems, patients' and nursing staff satisfaction, nursing time, and cost-effectiveness were assessed with trial-specific structured questionnaires and tally sheets. In the EH arm data were available for all patients, whereas in the HME arm data were incomplete for four patients. The 24/7 compliance rate in the EH arm was 12% and in the HME arm 87% (77% if the four nonevaluable patients are considered noncompliant). Compliance and patients' satisfaction were significantly better, and the number of coughing episodes, mucus expectoration for clearing the trachea, and sleeping disturbances were significantly less in the HME arm (P < .001). This was also the case for nursing time and nursing staff satisfaction and preference. This RCT clearly shows the benefits of immediate postoperative airway humidification by means of an HME over the use of an EH after TLE. This study therefore underlines that HMEs presently can be considered the better option for early postoperative airway humidification after TLE. Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.

  18. Psychological Effects of Automated External Defibrillator Training A randomized trial

    PubMed Central

    Meischke, Hendrika; Diehr, Paula; Phelps, Randi; Damon, Susan; Rea, Tom

    2011-01-01

    Objectives The objective of this study was to test if an Automated External Defibrillator (AED) training program would positively affect the mental health of family members of high risk patients. Methods 305 ischemic heart disease patients and their family members were randomized to one of four AED training programs: two video-based training programs and two face-to-face training programs that emphasized self-efficacy and perceived control. Patients and family members were surveyed at baseline, 3 and 9 months post ischemic event on demographic characteristics, measures of quality of life (SF=36) , self-efficacy and perceived control. For this study, family members were the focus rather than the patients. Results Regression analyses showed that family members in the face-to-face training programs did not score better on any of the mental health status variables than family members who participated in the other training programs but for an increase in self-efficacy beliefs at 3 months post training. Conclusion The findings suggest that a specifically designed AED training program emphasizing self-efficacy and perceived control beliefs is not likely to enhance family member mental health. PMID:21411144

  19. Outsourcing in public hospitals: a Greek perspective.

    PubMed

    Moschuris, Socrates J; Kondylis, Michael N

    2006-01-01

    The purpose of this research is to investigate the extent of outsourcing, the decision-making process, the impact of outsourcing, and the future trend of outsourcing in public hospitals in Greece. A survey instrument was designed and mailed to a random sample of 100 public hospitals in Greece and 43 usable questionnaires were received, representing a response rate of 43 percent. The survey instrument focused on the extent to which public hospitals outsource services, the decision-making process for choosing an external service provider, the impact of outsourcing, and the future trend of outsourcing in public healthcare organisations. Public hospitals in Greece outsource a variety of activities. Cost savings and customer satisfaction are the main factors affecting the outsourcing decision. The cooperation with a contract service provider has led to significant improvement in service quality levels. Most users are satisfied with the performance of these companies and believe that there will be an increase in the usage of these services in the future. It provides a decision-making framework regarding outsourcing in public healthcare organisations. This research fills the gap in the area of outsourcing in public hospitals in Greece.

  20. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sadovskii, V. M., E-mail: sadov@icm.krasn.ru; Sadovskaya, O. V., E-mail: o-sadov@icm.krasn.ru

    Based on the generalized rheological method, the mathematical model describing small deformations of a single-phase porous medium without regard to the effects of a fluid or gas in pores is constructed. The change in resistance of a material to the external mechanical impacts at the moment of pore collapse is taken into account by means of the von Mises–Schleicher strength condition. In order to consider irreversible deformations, alongside with the classical yield conditions by von Mises and Tresca– Saint-Venant, the special condition modeling the plastic loss of stability of a porous skeleton is used. The random nature of the poremore » size distribution is taken into account. It is shown that the proposed mathematical model satisfies the principles of thermodynamics of irreversible processes. Phenomenological parameters of the model are determined on the basis of the approximate calculation of the problem on quasi-static loading of a cubic periodicity cell with spherical voids. In the framework of the obtained model, the process of propagation of plane longitudinal waves of the compression in a homogenous porous medium, accompanied by the plastic deformation of a skeleton and the collapse of pores, is analyzed.« less

  1. Vector Analysis of Ionic Collision on CaCO3 Precipitation Based on Vibration Time History

    NASA Astrophysics Data System (ADS)

    Mangestiyono, W.; Muryanto, S.; Jamari, J.; Bayuseno, A. P.

    2017-05-01

    Vibration effects on the piping system can result from the internal factor of fluid or the external factor of the mechanical equipment operation. As the pipe vibrated, the precipitation process of CaCO3 on the inner pipe could be affected. In the previous research, the effect of vibration on CaCO3 precipitation in piping system was clearly verified. This increased the deposition rate and decreased the induction time. However, the mechanism of vibration control in CaCO3 precipitation process as the presence of vibration has not been recognized yet. In the present research, the mechanism of vibration affecting the CaCO3 precipitation was investigated through vector analysis of ionic collision. The ionic vector force was calculated based on the amount of the activation energy and the vibration force was calculated based on the vibration sensor data. The vector resultant of ionic collision based on the vibration time history was analyzed to prove that vibration brings ionic collision randomly to the planar horizontal direction and its collision model was suspected as the cause of the increasing deposition rate.

  2. The impact of innovation intermediary on knowledge transfer

    NASA Astrophysics Data System (ADS)

    Lin, Min; Wei, Jun

    2018-07-01

    Many firms have opened up their innovation process and actively transfer knowledge with external partners in the market of technology. To reduce some of the market inefficiencies, more and more firms collaborate with innovation intermediaries. In light of the increasing importance of intermediary in the context of open innovation, we in this paper systematically investigate the effect of innovation intermediary on knowledge transfer and innovation process in networked systems. We find that the existence of innovation intermediary is conducive to the knowledge diffusion and facilitate the knowledge growth at system level. Interestingly, the scale of the innovation intermediary has little effect on the growth of knowledge. We further investigate the selection of intermediary members by comparing four selection strategies: random selection, initial knowledge level based selection, absorptive capability based selection, and innovative ability based selection. It is found that the selection strategy based on innovative ability outperforms all the other strategies in promoting the system knowledge growth. Our study provides a theoretical understanding of the impact of innovation intermediary on knowledge transfer and sheds light on the design and selection of innovation intermediary in open innovation.

  3. Detecting the Influence of Spreading in Social Networks with Excitable Sensor Networks

    PubMed Central

    Pei, Sen; Tang, Shaoting; Zheng, Zhiming

    2015-01-01

    Detecting spreading outbreaks in social networks with sensors is of great significance in applications. Inspired by the formation mechanism of humans’ physical sensations to external stimuli, we propose a new method to detect the influence of spreading by constructing excitable sensor networks. Exploiting the amplifying effect of excitable sensor networks, our method can better detect small-scale spreading processes. At the same time, it can also distinguish large-scale diffusion instances due to the self-inhibition effect of excitable elements. Through simulations of diverse spreading dynamics on typical real-world social networks (Facebook, coauthor, and email social networks), we find that the excitable sensor networks are capable of detecting and ranking spreading processes in a much wider range of influence than other commonly used sensor placement methods, such as random, targeted, acquaintance and distance strategies. In addition, we validate the efficacy of our method with diffusion data from a real-world online social system, Twitter. We find that our method can detect more spreading topics in practice. Our approach provides a new direction in spreading detection and should be useful for designing effective detection methods. PMID:25950181

  4. PLNoise: a package for exact numerical simulation of power-law noises

    NASA Astrophysics Data System (ADS)

    Milotti, Edoardo

    2006-08-01

    Many simulations of stochastic processes require colored noises: here I describe a small program library that generates samples with a tunable power-law spectral density: the algorithm can be modified to generate more general colored noises, and is exact for all time steps, even when they are unevenly spaced (as may often happen in the case of astronomical data, see e.g. [N.R. Lomb, Astrophys. Space Sci. 39 (1976) 447]. The method is exact in the sense that it reproduces a process that is theoretically guaranteed to produce a range-limited power-law spectrum 1/f with -1<β⩽1. The algorithm has a well-behaved computational complexity, it produces a nearly perfect Gaussian noise, and its computational efficiency depends on the required degree of noise Gaussianity. Program summaryTitle of program: PLNoise Catalogue identifier:ADXV_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADXV_v1_0.html Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Licensing provisions: none Programming language used: ANSI C Computer: Any computer with an ANSI C compiler: the package has been tested with gcc version 3.2.3 on Red Hat Linux 3.2.3-52 and gcc version 4.0.0 and 4.0.1 on Apple Mac OS X-10.4 Operating system: All operating systems capable of running an ANSI C compiler No. of lines in distributed program, including test data, etc.:6238 No. of bytes in distributed program, including test data, etc.:52 387 Distribution format:tar.gz RAM: The code of the test program is very compact (about 50 Kbytes), but the program works with list management and allocates memory dynamically; in a typical run (like the one discussed in Section 4 in the long write-up) with average list length 2ṡ10, the RAM taken by the list is 200 Kbytes. External routines: The package needs external routines to generate uniform and exponential deviates. The implementation described here uses the random number generation library ranlib freely available from Netlib [B.W. Brown, J. Lovato, K. Russell, ranlib, available from Netlib, http://www.netlib.org/random/index.html, select the C version ranlib.c], but it has also been successfully tested with the random number routines in Numerical Recipes [W.H. Press, S.A. Teulkolsky, W.T. Vetterling, B.P. Flannery, Numerical Recipes in C: The Art of Scientific Computing, second ed., Cambridge Univ. Press, Cambridge, 1992, pp. 274-290]. Notice that ranlib requires a pair of routines from the linear algebra package LINPACK, and that the distribution of ranlib includes the C source of these routines, in case LINPACK is not installed on the target machine. Nature of problem: Exact generation of different types of Gaussian colored noise. Solution method: Random superposition of relaxation processes [E. Milotti, Phys. Rev. E 72 (2005) 056701]. Unusual features: The algorithm is theoretically guaranteed to be exact, and unlike all other existing generators it can generate samples with uneven spacing. Additional comments: The program requires an initialization step; for some parameter sets this may become rather heavy. Running time: Running time varies widely with different input parameters, however in a test run like the one in Section 4 in this work, the generation routine took on average about 7 ms for each sample.

  5. Slip-Size Distribution and Self-Organized Criticality in Block-Spring Models with Quenched Randomness

    NASA Astrophysics Data System (ADS)

    Sakaguchi, Hidetsugu; Kadowaki, Shuntaro

    2017-07-01

    We study slowly pulling block-spring models in random media. Second-order phase transitions exist in a model pulled by a constant force in the case of velocity-strengthening friction. If external forces are slowly increased, nearly critical states are self-organized. Slips of various sizes occur, and the probability distributions of slip size roughly obey power laws. The exponent is close to that in the quenched Edwards-Wilkinson model. Furthermore, the slip-size distributions are investigated in cases of Coulomb friction, velocity-weakening friction, and two-dimensional block-spring models.

  6. Synchronised firing patterns in a random network of adaptive exponential integrate-and-fire neuron model.

    PubMed

    Borges, F S; Protachevicz, P R; Lameu, E L; Bonetti, R C; Iarosz, K C; Caldas, I L; Baptista, M S; Batista, A M

    2017-06-01

    We have studied neuronal synchronisation in a random network of adaptive exponential integrate-and-fire neurons. We study how spiking or bursting synchronous behaviour appears as a function of the coupling strength and the probability of connections, by constructing parameter spaces that identify these synchronous behaviours from measurements of the inter-spike interval and the calculation of the order parameter. Moreover, we verify the robustness of synchronisation by applying an external perturbation to each neuron. The simulations show that bursting synchronisation is more robust than spike synchronisation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Sources of Information as Determinants of Product and Process Innovation.

    PubMed

    Gómez, Jaime; Salazar, Idana; Vargas, Pilar

    2016-01-01

    In this paper we use a panel of manufacturing firms in Spain to examine the extent to which they use internal and external sources of information (customers, suppliers, competitors, consultants and universities) to generate product and process innovation. Our results show that, although internal sources are influential, external sources of information are key to achieve innovation performance. These results are in line with the open innovation literature because they show that firms that are opening up their innovation process and that use different information sources have a greater capacity to generate innovations. We also find that the importance of external sources of information varies depending on the type of innovation (product or process) considered. To generate process innovation, firms mainly rely on suppliers while, to generate product innovation, the main contribution is from customers. The potential simultaneity between product and process innovation is also taken into consideration. We find that the generation of both types of innovation is not independent.

  8. Sources of Information as Determinants of Product and Process Innovation

    PubMed Central

    2016-01-01

    In this paper we use a panel of manufacturing firms in Spain to examine the extent to which they use internal and external sources of information (customers, suppliers, competitors, consultants and universities) to generate product and process innovation. Our results show that, although internal sources are influential, external sources of information are key to achieve innovation performance. These results are in line with the open innovation literature because they show that firms that are opening up their innovation process and that use different information sources have a greater capacity to generate innovations. We also find that the importance of external sources of information varies depending on the type of innovation (product or process) considered. To generate process innovation, firms mainly rely on suppliers while, to generate product innovation, the main contribution is from customers. The potential simultaneity between product and process innovation is also taken into consideration. We find that the generation of both types of innovation is not independent. PMID:27035456

  9. Use of adjunctive mitomycin C in external dacryocystorhinostomy surgery compared with surgery alone in patients with nasolacrimal duct obstruction: A prospective, double-masked, randomized, controlled trial.

    PubMed

    Ari, Seyhmus; Gun, Ramazan; Surmeli, Serdar; Atay, Ahmet Engin; Caca, Ihsan

    2009-08-01

    The most common cause for the failure of external dacryocystorhinostomy (DCR) surgery is the formation of granulation tissue at the osteotomy site or common canaliculus. The aims of this study were to assess the efficacy of intraoperative adjunctive mitomycin C (MMC) treatment in external DCR surgery and to compare this procedure with the standard DCR procedure alone in the long term (1 year). In this prospective, double-masked, randomized, controlled trial, patients with primary acquired nasolacrimal duct obstruction were randomized (using a random number table) into 2 groups based on surgical procedure. In the MMC group, intraoperative adjunctive MMC 0.2 mg/mL was applied to the osteotomy site for 30 minutes. The control group underwent standard DCR procedure only. The results of the DCR surgeries were assessed using objective findings (eg, cessation of excessive tearing via nasolacrimal duct irrigation and the improvement in height of tear meniscus) and subjective symptoms (asking patients to describe the degree of tearing improvement). Both the patients and the researchers who were assessing the study outcomes were masked to treatment group. One hundred eyes of 100 Turkish patients were assessed and equally randomized to the MMC (27 women, 23 men; mean [SD] age, 47.0 [7.6] years) and control (26 women, 24 men; mean age, 46.6 [8.8] years) groups. The follow-up period was not significantly different between the MMC and the control groups (13.1 [1.1] vs 13.2 [1.4] months). Significantly more eyes in the MMC group than the control group remained symptom-free throughout the 1-year follow-up period (45/50 [90%] vs 33/50 [66%]; P=0.005). Significantly more patients in the control group than the MMC group had an improvement in symptoms at the 1-year follow-up (8/50 [16%] vs 2/50 [4%] eyes; P=0.005). Based on the patency of the drainage system, the success rate was significantly greater in the MMC group than the control group (48/50 [96%] vs 42/50 [84%]; P=0.005). Based on nasolacrimal duct irrigation, significantly fewer patients in the MMC group than the control group had an enclosed naso-lacrimal duct (2/50 [4%] vs 8/50 [16%]). No adverse effects (eg, abnormal nasal bleeding, mucosal necrosis, infection) or any other surgical adverse events were observed. In the management of these patients with primary acquired nasolacrimal duct obstruction, adjunctive intraoperative MMC application with standard DCR surgery had a significantly higher success rate than did standard DCR surgery alone. Further large, double-masked, randomized studies are needed to confirm these findings.

  10. Use of adjunctive mitomycin C in external dacryocystorhinostomy surgery compared with surgery alone in patients with nasolacrimal duct obstruction: A prospective, double-masked, randomized, controlled trial

    PubMed Central

    Ari, Şeyhmus; Gun, Ramazan; Surmeli, Serdar; Atay, Ahmet Engin; Çaca, Îhsan

    2009-01-01

    Background: The most common cause for the failure of external dacryocystorhinostomy (DCR) surgery is the formation of granulation tissue at the osteotomy site or common canaliculus. Objectives: The aims of this study were to assess the efficacy of intraoperative adjunctive mitomycin C (MMC) treatment in external DCR surgery and to compare this procedure with the standard DCR procedure alone in the long term (1 year). Methods: In this prospective, double-masked, randomized, controlled trial, patients with primary acquired nasolacrimal duct obstruction were randomized (using a random number table) into 2 groups based on surgical procedure. In the MMC group, intraoperative adjunctive MMC 0.2 mg/mL was applied to the osteotomy site for 30 minutes. The control group underwent standard DCR procedure only. The results of the DCR surgeries were assessed using objective findings (eg, cessation of excessive tearing via nasolacrimal duct irrigation and the improvement in height of tear meniscus) and subjective symptoms (asking patients to describe the degree of tearing improvement). Both the patients and the researchers who were assessing the study outcomes were masked to treatment group. Results: One hundred eyes of 100 Turkish patients were assessed and equally randomized to the MMC (27 women, 23 men; mean [SD] age, 47.0 [7.6] years) and control (26 women, 24 men; mean age, 46.6 [8.8] years) groups. The follow-up period was not significantly different between the MMC and the control groups (13.1 [1.1] vs 13.2 [1.4] months). Significantly more eyes in the MMC group than the control group remained symptom-free throughout the 1-year follow-up period (45/50 [90%] vs 33/50 [66%]; P=0.005). Significantly more patients in the control group than the MMC group had an improvement in symptoms at the 1-year follow-up (8/50 [16%] vs 2/50 [4%] eyes; P=0.005). Based on the patency of the drainage system, the success rate was significantly greater in the MMC group than the control group (48/50 [96%] vs 42/50 [84%]; P=0.005). Based on nasolacrimal duct irrigation, significantly fewer patients in the MMC group than the control group had an enclosed naso-lacrimal duct (2/50 [4%] vs 8/50 [16%]). No adverse effects (eg, abnormal nasal bleeding, mucosal necrosis, infection) or any other surgical adverse events were observed. Conclusions: In the management of these patients with primary acquired nasolacrimal duct obstruction, adjunctive intraoperative MMC application with standard DCR surgery had a significantly higher success rate than did standard DCR surgery alone. Further large, double-masked, randomized studies are needed to confirm these findings. PMID:24683236

  11. 76 FR 11283 - Agency Information Collection Activities; Submission for OMB Review; Comment Request; Affordable...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-01

    ... for OMB Review; Comment Request; Affordable Care Act Internal Claims and Appeals and External Review...) titled, ``Affordable Care Act Internal Claims and Appeals and External Review Procedures for Non... rules relating to internal claims and appeals and external review processes. On July 23, 2010, the EBSA...

  12. Dual Learning Processes in Interactive Skill Acquisition

    ERIC Educational Resources Information Center

    Fu, Wai-Tat; Anderson, John R.

    2008-01-01

    Acquisition of interactive skills involves the use of internal and external cues. Experiment 1 showed that when actions were interdependent, learning was effective with and without external cues in the single-task condition but was effective only with the presence of external cues in the dual-task condition. In the dual-task condition, actions…

  13. Teachers' Views of the Impact of School Evaluation and External Inspection Processes

    ERIC Educational Resources Information Center

    Hopkins, Elizabeth; Hendry, Helen; Garrod, Frank; McClare, Siobhan; Pettit, Daniel; Smith, Luke; Burrell, Hannah; Temple, Jennifer

    2016-01-01

    The research explores the views of teachers about how their teaching is evaluated by others. The tensions between evaluations motivated by the drive to improve practice (school self-evaluation) and evaluation related to external accountability (external evaluation-inspection) are considered, linked to findings and ideas reported in the literature.…

  14. The External Contingencies and Development Processes of Students with Emotional Disabilities

    ERIC Educational Resources Information Center

    Nikolaros, John

    2015-01-01

    This paper examines the external contingencies that students with emotional disabilities (ED) experience throughout childhood and adolescence. It presents an in-depth assessment of the impact of external dynamics on the emotional development of students with ED, and considers the school, home, and community support systems. The paper assesses…

  15. The Association between Positive Parenting and Externalizing Behavior.

    PubMed

    Boeldt, Debra L; Rhee, Soo Hyun; Dilalla, Lisabeth F; Mullineaux, Paula Y; Schulz-Heik, R Jay; Corley, Robin P; Young, Susan E; Hewitt, John K

    2012-01-01

    The present study examined the role of positive parenting on externalizing behaviors in a longitudinal, genetically informative sample. It often is assumed that positive parenting prevents behavior problems in children via an environmentally mediated process. Alternatively, the association may be due to either an evocative gene-environment correlation, in which parents react to children's genetically-influenced behavior in a positive way, or a passive gene-environment correlation, where parents passively transmit a risk environment and the genetic risk factor for the behavioral outcome to their children. The present study estimated the contribution of these processes in the association between positive parenting and children's externalizing behavior. Positive parenting was assessed via observations at ages 7, 9, 14, 24, and 36 months and externalizing behaviors were assessed through parent report at ages 4, 5, 7, 9, 10, 11, and 12 years. The significant association between positive parenting and externalizing behavior was negative, with children of mothers who showed significantly more positive parenting during toddlerhood having lower levels of externalizing behavior in childhood; however, there was not adequate power to distinguish whether this covariation was due to genetic, shared environmental, or nonshared environmental influences.

  16. Surface electromyography activity of the rectus abdominis, internal oblique, and external oblique muscles during forced expiration in healthy adults.

    PubMed

    Ito, Kenichi; Nonaka, Koji; Ogaya, Shinya; Ogi, Atsushi; Matsunaka, Chiaki; Horie, Jun

    2016-06-01

    We aimed to characterize rectus abdominis, internal oblique, and external oblique muscle activity in healthy adults under expiratory resistance using surface electromyography. We randomly assigned 42 healthy adult subjects to 3 groups: 30%, 20%, and 10% maximal expiratory intraoral pressure (PEmax). After measuring 100% PEmax and muscle activity during 100% PEmax, the activity and maximum voluntary contraction of each muscle during the assigned experimental condition were measured. At 100% PEmax, the external oblique (p<0.01) and internal oblique (p<0.01) showed significantly elevated activity compared with the rectus abdominis muscle. Furthermore, at 20% and 30% PEmax, the external oblique (p<0.05 and<0.01, respectively) and the internal oblique (p<0.05 and<0.01, respectively) showed significantly elevated activity compared with the rectus abdominis muscle. At 10% PEmax, no significant differences were observed in muscle activity. Although we observed no significant difference between 10% and 20% PEmax, activity during 30% PEmax was significantly greater than during 20% PEmax (external oblique: p<0.05; internal oblique: p<0.01). The abdominal oblique muscles are the most active during forced expiration. Moreover, 30% PEmax is the minimum intensity required to achieve significant, albeit very slight, muscle activity during expiratory resistance. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Social capital, political trust, and health locus of control: a population-based study.

    PubMed

    Lindström, Martin

    2011-02-01

    To investigate the association between political trust in the Riksdag and lack of belief in the possibility to influence one's own health (external locus of control), taking horizontal trust into account. The 2008 public health survey in Skåne is a cross-sectional postal questionnaire study with a 55% participation rate. A random sample of 28,198 persons aged 18-80 years participated. Logistic regression models were used to investigate the associations between political trust in the Riksdag (an aspect of vertical trust) and lack of belief in the possibility to influence one's own health (external locus of control). The multiple regression analyses included age, country of birth, education, and horizontal trust in other people. A 33.7% of all men and 31.8% of all women lack internal locus of control. Low (external) health locus of control is more common in higher age groups, among people born outside Sweden, with lower education, low horizontal trust, low political trust, and no opinion concerning political trust. Respondents with not particularly strong political trust, no political trust at all and no opinion have significantly higher odds ratios of external locus of control throughout the multiple regression analyses. Low political trust in the Riksdag seems to be independently associated with external health locus of control.

  18. The Effectiveness of Parent Management Training-Oregon Model in Clinically Referred Children with Externalizing Behavior Problems in The Netherlands.

    PubMed

    Thijssen, Jill; Vink, Gerko; Muris, Peter; de Ruiter, Corine

    2017-02-01

    The present study examined the effectiveness of parent management training-Oregon model (PMTO) as a treatment for children with externalizing behavior problems in The Netherlands. Clinically referred children (N = 146) aged 4-11 years and their parents were partly randomized to either PMTO (n = 91) or Care As Usual (CAU; n = 55). Families were assessed at four time points: at pretreatment, and after 6, 12, and 18 months. Results showed that both PMTO and CAU were effective in reducing child externalizing behavior, parenting stress and parental psychopathology, with no significant differences between the two treatment conditions. PMTO and CAU interventions also produced some improvements in self-reported parenting skills, but not in observed parenting skills. According to the Reliable Change Index, 16.9 and 45.8 % of the children within the PMTO group showed full recovery or improvement in externalizing behavior, respectively, versus 9.7 and 42.8 % in the CAU condition. Finally, the effect size of PMTO on parent-reported externalizing behavior problems as found in the present study was comparable to that found in previous studies evaluating PMTO as an intervention for this type of child psychopathology.

  19. Swim stress, motion, and deformation of active matter: effect of an external field.

    PubMed

    Takatori, Sho C; Brady, John F

    2014-12-21

    We analyze the stress, dispersion, and average swimming speed of self-propelled particles subjected to an external field that affects their orientation and speed. The swimming trajectory is governed by a competition between the orienting influence (i.e., taxis) associated with the external (e.g., magnetic, gravitational, thermal, nutrient concentration) field versus the effects that randomize the particle orientations (e.g., rotary Brownian motion and/or an intrinsic tumbling mechanism like the flagella of bacteria). The swimmers' motion is characterized by a mean drift velocity and an effective translational diffusivity that becomes anisotropic in the presence of the orienting field. Since the diffusivity yields information about the micromechanical stress, the anisotropy generated by the external field creates a normal stress difference in the recently developed "swim stress" tensor [Takatori, Yan, and Brady, Phys. Rev. Lett., 2014]. This property can be exploited in the design of soft, compressible materials in which their size, shape, and motion can be manipulated and tuned by loading the material with active swimmers. Since the swimmers exert different normal stresses in different directions, the material can compress/expand, elongate, and translate depending on the external field strength. Such an active system can be used as nano/micromechanical devices and motors. Analytical solutions are corroborated by Brownian dynamics simulations.

  20. Ant groups optimally amplify the effect of transiently informed individuals

    NASA Astrophysics Data System (ADS)

    Gelblum, Aviram; Pinkoviezky, Itai; Fonio, Ehud; Ghosh, Abhijit; Gov, Nir; Feinerman, Ofer

    2015-07-01

    To cooperatively transport a large load, it is important that carriers conform in their efforts and align their forces. A downside of behavioural conformism is that it may decrease the group's responsiveness to external information. Combining experiment and theory, we show how ants optimize collective transport. On the single-ant scale, optimization stems from decision rules that balance individuality and compliance. Macroscopically, these rules poise the system at the transition between random walk and ballistic motion where the collective response to the steering of a single informed ant is maximized. We relate this peak in response to the divergence of susceptibility at a phase transition. Our theoretical models predict that the ant-load system can be transitioned through the critical point of this mesoscopic system by varying its size; we present experiments supporting these predictions. Our findings show that efficient group-level processes can arise from transient amplification of individual-based knowledge.

  1. Estimating the domain of applicability for machine learning QSAR models: a study on aqueous solubility of drug discovery molecules.

    PubMed

    Schroeter, Timon Sebastian; Schwaighofer, Anton; Mika, Sebastian; Ter Laak, Antonius; Suelzle, Detlev; Ganzer, Ursula; Heinrich, Nikolaus; Müller, Klaus-Robert

    2007-12-01

    We investigate the use of different Machine Learning methods to construct models for aqueous solubility. Models are based on about 4000 compounds, including an in-house set of 632 drug discovery molecules of Bayer Schering Pharma. For each method, we also consider an appropriate method to obtain error bars, in order to estimate the domain of applicability (DOA) for each model. Here, we investigate error bars from a Bayesian model (Gaussian Process (GP)), an ensemble based approach (Random Forest), and approaches based on the Mahalanobis distance to training data (for Support Vector Machine and Ridge Regression models). We evaluate all approaches in terms of their prediction accuracy (in cross-validation, and on an external validation set of 536 molecules) and in how far the individual error bars can faithfully represent the actual prediction error.

  2. Estimating the domain of applicability for machine learning QSAR models: a study on aqueous solubility of drug discovery molecules.

    PubMed

    Schroeter, Timon Sebastian; Schwaighofer, Anton; Mika, Sebastian; Ter Laak, Antonius; Suelzle, Detlev; Ganzer, Ursula; Heinrich, Nikolaus; Müller, Klaus-Robert

    2007-09-01

    We investigate the use of different Machine Learning methods to construct models for aqueous solubility. Models are based on about 4000 compounds, including an in-house set of 632 drug discovery molecules of Bayer Schering Pharma. For each method, we also consider an appropriate method to obtain error bars, in order to estimate the domain of applicability (DOA) for each model. Here, we investigate error bars from a Bayesian model (Gaussian Process (GP)), an ensemble based approach (Random Forest), and approaches based on the Mahalanobis distance to training data (for Support Vector Machine and Ridge Regression models). We evaluate all approaches in terms of their prediction accuracy (in cross-validation, and on an external validation set of 536 molecules) and in how far the individual error bars can faithfully represent the actual prediction error.

  3. Precision gravity measurement utilizing Accelerex vibrating beam accelerometer technology

    NASA Astrophysics Data System (ADS)

    Norling, Brian L.

    Tests run using Sundstrand vibrating beam accelerometers to sense microgravity are described. Lunar-solar tidal effects were used as a highly predictable signal which varies by approximately 200 billionths of the full-scale gravitation level. Test runs of 48-h duration were used to evaluate stability, resolution, and noise. Test results on the Accelerex accelerometer show accuracies suitable for precision applications such as gravity mapping and gravity density logging. The test results indicate that Accelerex technology, even with an instrument design and signal processing approach not optimized for microgravity measurement, can achieve 48-nano-g (1 sigma) or better accuracy over a 48-h period. This value includes contributions from instrument noise and random walk, combined bias and scale factor drift, and thermal modeling errors as well as external contributions from sampling noise, test equipment inaccuracies, electrical noise, and cultural noise induced acceleration.

  4. Ion Conduction in Microphase-Separated Block Copolymer Electrolytes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kambe, Yu; Arges, Christopher G.; Patel, Shrayesh

    2017-01-01

    Microphase separation of block copolymers provides a promising route towards engineering a mechanically robust ion conducting film for electrochemical devices. The separation into two different nano-domains enables the film to simultaneously exhibit both high ion conductivity and mechanical robustness, material properties inversely related in most homopolymer and random copolymer electrolytes. To exhibit the maximum conductivity and mechanical robustness, both domains would span across macroscopic length scales enabling uninterrupted ion conduction. One way to achieve this architecture is through external alignment fields that are applied during the microphase separation process. In this review, we present the progress and challenges for aligningmore » the ionic domains in block copolymer electrolytes. A survey of alignment and characterization is followed by a discussion of how the nanoscale architecture affects the bulk conductivity and how alignment may be improved to maximize the number of participating conduction domains.« less

  5. Estimating the domain of applicability for machine learning QSAR models: a study on aqueous solubility of drug discovery molecules

    NASA Astrophysics Data System (ADS)

    Schroeter, Timon Sebastian; Schwaighofer, Anton; Mika, Sebastian; Ter Laak, Antonius; Suelzle, Detlev; Ganzer, Ursula; Heinrich, Nikolaus; Müller, Klaus-Robert

    2007-12-01

    We investigate the use of different Machine Learning methods to construct models for aqueous solubility. Models are based on about 4000 compounds, including an in-house set of 632 drug discovery molecules of Bayer Schering Pharma. For each method, we also consider an appropriate method to obtain error bars, in order to estimate the domain of applicability (DOA) for each model. Here, we investigate error bars from a Bayesian model (Gaussian Process (GP)), an ensemble based approach (Random Forest), and approaches based on the Mahalanobis distance to training data (for Support Vector Machine and Ridge Regression models). We evaluate all approaches in terms of their prediction accuracy (in cross-validation, and on an external validation set of 536 molecules) and in how far the individual error bars can faithfully represent the actual prediction error.

  6. Estimating the domain of applicability for machine learning QSAR models: a study on aqueous solubility of drug discovery molecules

    NASA Astrophysics Data System (ADS)

    Schroeter, Timon Sebastian; Schwaighofer, Anton; Mika, Sebastian; Ter Laak, Antonius; Suelzle, Detlev; Ganzer, Ursula; Heinrich, Nikolaus; Müller, Klaus-Robert

    2007-09-01

    We investigate the use of different Machine Learning methods to construct models for aqueous solubility. Models are based on about 4000 compounds, including an in-house set of 632 drug discovery molecules of Bayer Schering Pharma. For each method, we also consider an appropriate method to obtain error bars, in order to estimate the domain of applicability (DOA) for each model. Here, we investigate error bars from a Bayesian model (Gaussian Process (GP)), an ensemble based approach (Random Forest), and approaches based on the Mahalanobis distance to training data (for Support Vector Machine and Ridge Regression models). We evaluate all approaches in terms of their prediction accuracy (in cross-validation, and on an external validation set of 536 molecules) and in how far the individual error bars can faithfully represent the actual prediction error.

  7. Negative differential mobility in interacting particle systems

    NASA Astrophysics Data System (ADS)

    Chatterjee, Amit Kumar; Basu, Urna; Mohanty, P. K.

    2018-05-01

    Driven particles in the presence of crowded environment, obstacles, or kinetic constraints often exhibit negative differential mobility (NDM) due to their decreased dynamical activity. Based on the empirical studies of conserved lattice gas model, two species exclusion model and other interacting particle systems we propose a new mechanism for complex many-particle systems where slowing down of certain non-driven degrees of freedom by the external field can give rise to NDM. To prove that the slowing down of the non-driven degrees is indeed the underlying cause, we consider several driven diffusive systems including two species exclusion models, misanthrope process, and show from the exact steady state results that NDM indeed appears when some non-driven modes are slowed down deliberately. For clarity, we also provide a simple pedagogical example of two interacting random walkers on a ring which conforms to the proposed scenario.

  8. Recurrent Network models of sequence generation and memory

    PubMed Central

    Rajan, Kanaka; Harvey, Christopher D; Tank, David W

    2016-01-01

    SUMMARY Sequential activation of neurons is a common feature of network activity during a variety of behaviors, including working memory and decision making. Previous network models for sequences and memory emphasized specialized architectures in which a principled mechanism is pre-wired into their connectivity. Here, we demonstrate that starting from random connectivity and modifying a small fraction of connections, a largely disordered recurrent network can produce sequences and implement working memory efficiently. We use this process, called Partial In-Network training (PINning), to model and match cellular-resolution imaging data from the posterior parietal cortex during a virtual memory-guided two-alternative forced choice task [Harvey, Coen and Tank, 2012]. Analysis of the connectivity reveals that sequences propagate by the cooperation between recurrent synaptic interactions and external inputs, rather than through feedforward or asymmetric connections. Together our results suggest that neural sequences may emerge through learning from largely unstructured network architectures. PMID:26971945

  9. Memristive behavior of the SnO2/TiO2 interface deposited by sol-gel

    NASA Astrophysics Data System (ADS)

    Boratto, Miguel H.; Ramos, Roberto A.; Congiu, Mirko; Graeff, Carlos F. O.; Scalvi, Luis V. A.

    2017-07-01

    A novel and cheap Resistive Random Access Memory (RRAM) device is proposed within this work, based on the interface between antimony doped Tin Oxide (4%at Sb:SnO2) and Titanium Oxide (TiO2) thin films, entirely prepared through a low-temperature sol-gel process. The device was fabricated on glass slides using evaporated aluminum electrodes. Typical bipolar memristive behavior under cyclic voltage sweeping and square wave voltages, with well-defined high and low resistance states (HRS and LRS), and set and reset voltages are shown in our samples. The switching mechanism, explained by charges trapping/de-trapping by defects in the SnO2/TiO2 interface, is mainly driven by the external electric field. The calculated on/off ratio was about 8 × 102 in best conditions with good reproducibility over repeated measurement cycles under cyclic voltammetry and about 102 under applied square wave voltage.

  10. Self Organized Criticality as a new paradigm of sleep regulation

    NASA Astrophysics Data System (ADS)

    Ivanov, Plamen Ch.; Bartsch, Ronny P.

    2012-02-01

    Humans and animals often exhibit brief awakenings from sleep (arousals), which are traditionally viewed as random disruptions of sleep caused by external stimuli or pathologic perturbations. However, our recent findings show that arousals exhibit complex temporal organization and scale-invariant behavior, characterized by a power-law probability distribution for their durations, while sleep stage durations exhibit exponential behavior. The co-existence of both scale-invariant and exponential processes generated by a single regulatory mechanism has not been observed in physiological systems until now. Such co-existence resembles the dynamical features of non-equilibrium systems exhibiting self-organized criticality (SOC). Our empirical analysis and modeling approaches based on modern concepts from statistical physics indicate that arousals are an integral part of sleep regulation and may be necessary to maintain and regulate healthy sleep by releasing accumulated excitations in the regulatory neuronal networks, following a SOC-type temporal organization.

  11. Ant groups optimally amplify the effect of transiently informed individuals

    PubMed Central

    Gelblum, Aviram; Pinkoviezky, Itai; Fonio, Ehud; Ghosh, Abhijit; Gov, Nir; Feinerman, Ofer

    2015-01-01

    To cooperatively transport a large load, it is important that carriers conform in their efforts and align their forces. A downside of behavioural conformism is that it may decrease the group's responsiveness to external information. Combining experiment and theory, we show how ants optimize collective transport. On the single-ant scale, optimization stems from decision rules that balance individuality and compliance. Macroscopically, these rules poise the system at the transition between random walk and ballistic motion where the collective response to the steering of a single informed ant is maximized. We relate this peak in response to the divergence of susceptibility at a phase transition. Our theoretical models predict that the ant-load system can be transitioned through the critical point of this mesoscopic system by varying its size; we present experiments supporting these predictions. Our findings show that efficient group-level processes can arise from transient amplification of individual-based knowledge. PMID:26218613

  12. Experimental nonlinear dynamical studies in cesium magneto-optical trap using time-series analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Anwar, M., E-mail: mamalik2000@gmail.com; Islam, R.; Faisal, M.

    2015-03-30

    A magneto-optical trap of neutral atoms is essentially a dissipative quantum system. The fast thermal atoms continuously dissipate their energy to the environment via spontaneous emissions during the cooling. The atoms are, therefore, strongly coupled with the vacuum reservoir and the laser field. The vacuum fluctuations as well as the field fluctuations are imparted to the atoms as random photon recoils. Consequently, the external and internal dynamics of atoms becomes stochastic. In this paper, we have investigated the stochastic dynamics of the atoms in a magneto-optical trap during the loading process. The time series analysis of the fluorescence signal showsmore » that the dynamics of the atoms evolves, like all dissipative systems, from deterministic to the chaotic regime. The subsequent disappearance and revival of chaos was attributed to chaos synchronization between spatially different atoms in the magneto-optical trap.« less

  13. Parenting, attention and externalizing problems: testing mediation longitudinally, repeatedly and reciprocally.

    PubMed

    Belsky, Jay; Pasco Fearon, R M; Bell, Brian

    2007-12-01

    Building on prior work, this paper tests, longitudinally and repeatedly, the proposition that attentional control processes mediate the effect of earlier parenting on later externalizing problems. Repeated independent measurements of all three constructs--observed parenting, computer-tested attentional control and adult-reported externalizing problems--were subjected to structural equation modeling using data from the large-scale American study of child care and youth development. Structural equation modeling indicated (a) that greater maternal sensitivity at two different ages (54 months, approximately 6 years) predicted better attentional control on the Continuous Performance Test (CPT) of attention regulation two later ages ( approximately 6/9 years); (2) that better attentional control at three different ages (54 months, approximately 6/9 years) predicted less teacher-reported externalizing problems at three later ages ( approximately 6/8/10 years); and (3) that attentional control partially mediated the effect of parenting on externalizing problems at two different lags (i.e., 54 months--> approximately 6 years--> approximately 8 years; approximately 6 years--> approximately 9 years--> approximately 10 years), though somewhat more strongly for the first. Additionally, (4) some evidence of reciprocal effects of attentional processes on parenting emerged (54 months--> approximately 6 years; approximately 6 years--> approximately 8 years), but not of problem behavior on attention. Because attention control partially mediates the effects of parenting on externalizing problems, intervention efforts could target both parenting and attentional processes.

  14. Mothers' different styles of involvement in preterm infant pain care.

    PubMed

    Axelin, Anna; Lehtonen, Liisa; Pelander, Tiina; Salanterä, Sanna

    2010-01-01

    To describe and understand how mothers utilize the opportunity to actively participate in their preterm infants' pain care using facilitated tucking by parents (FTP). Descriptive and exploratory study with postintervention interview. Finnish level III Neonatal Intensive Care Unit (NICU). Twenty-three mothers who had preterm infants born at gestational ages of 32 to 34 weeks. The parents (N=45) of 29 preterm infants were taught to use FTP. In addition, all nurses in the NICU (N=76) received the same education to support the parents' use of FTP. After 2 to 4 weeks of FTP use, the mothers (n=23) were interviewed using the Clinical Interview for Parents of High-Risk Infants with additional questions related to the infants' pain care. The interviews were analyzed inductively with cross-case analysis and deductively with a previously developed coding scheme. Facilitated tucking by parents was perceived positively and was used by all participating mothers. Three different styles of involvement in preterm infants' pain care with FTP were identified. They formed a continuum from external to random and finally to internalized involvement. In external involvement, the pain care with FTP was triggered by outside factors such as nurses, whereas in random and internalized involvement the motivation emerged from a parent. Mothers with external involvement thought that any person could apply the FTP. In random involvement, mothers were mainly absent during painful procedures, although they saw themselves as the best caregivers. In internalized involvement, the responsibility for infant pain care was shared within the family. Mothers' NICU-related stress and maternal attachment were associated with this variation. This study showed that mothers' are willing to actively participate in their preterm infants' pain care. However, the participation is unique according to mother and her experiences before and during NICU admission. Nurses need to consider these differences in mothers when involving them in preterm infants' pain care.

  15. Use of 3D printed models in medical education: A randomized control trial comparing 3D prints versus cadaveric materials for learning external cardiac anatomy.

    PubMed

    Lim, Kah Heng Alexander; Loo, Zhou Yaw; Goldie, Stephen J; Adams, Justin W; McMenamin, Paul G

    2016-05-06

    Three-dimensional (3D) printing is an emerging technology capable of readily producing accurate anatomical models, however, evidence for the use of 3D prints in medical education remains limited. A study was performed to assess their effectiveness against cadaveric materials for learning external cardiac anatomy. A double blind randomized controlled trial was undertaken on undergraduate medical students without prior formal cardiac anatomy teaching. Following a pre-test examining baseline external cardiac anatomy knowledge, participants were randomly assigned to three groups who underwent self-directed learning sessions using either cadaveric materials, 3D prints, or a combination of cadaveric materials/3D prints (combined materials). Participants were then subjected to a post-test written by a third party. Fifty-two participants completed the trial; 18 using cadaveric materials, 16 using 3D models, and 18 using combined materials. Age and time since completion of high school were equally distributed between groups. Pre-test scores were not significantly different (P = 0.231), however, post-test scores were significantly higher for 3D prints group compared to the cadaveric materials or combined materials groups (mean of 60.83% vs. 44.81% and 44.62%, P = 0.010, adjusted P = 0.012). A significant improvement in test scores was detected for the 3D prints group (P = 0.003) but not for the other two groups. The finding of this pilot study suggests that use of 3D prints do not disadvantage students relative to cadaveric materials; maximally, results suggest that 3D may confer certain benefits to anatomy learning and supports their use and ongoing evaluation as supplements to cadaver-based curriculums. Anat Sci Educ 9: 213-221. © 2015 American Association of Anatomists. © 2015 American Association of Anatomists.

  16. Comparison of effects of seven treatment methods for distal radius fracture on minimizing complex regional pain syndrome

    PubMed Central

    Sun, Tao

    2016-01-01

    Introduction Using network meta-analysis, we evaluated the adverse effects of the seven most common treatment methods, i.e., bridging external fixation, non-bridging external fixation, K-wire fixation, plaster fixation, dorsal plating, volar plating, and dorsal and volar plating, by their associated risk of developing complex regional pain syndrome (CRPS) in distal radius fracture (DRF) patients. Material and methods Following an exhaustive search of scientific literature databases for high quality studies, randomized controlled trials (RCTs) related to our study topic were screened and selected based on stringent predefined inclusion and exclusion criteria. Data extracted from the selected studies were used for statistical analyses using Stata 12.0 software. Results A total of 17 RCTs, including 1658 DRF patients, were enrolled in this network meta-analysis. Among the 1658 DRF patients, 452 received bridging external fixation, 525 received non-bridging external fixation, 154 received K-wire fixation, 84 received plaster fixation, 132 received dorsal plating, 123 received volar plating, and 188 received dorsal and volar plating. When compared to bridging external fixation patients, there was no marked difference in the CRPS risk in DRF patients receiving different treatments (all p > 0.05). However, the surface under the cumulative ranking curves (SUCRA) for plaster fixation (77.0%) and non-bridging external fixation (71.3%) were significantly higher compared with the other five methods. Conclusions Our findings suggest that compared with bridging external fixation, K-wire fixation, dorsal plating, volar plating, dorsal and volar plating, plaster fixation and non-bridging external fixation might be the better treatment methods to reduce the risk of CRPS in DRF patients. PMID:28144268

  17. Targeting dopa-sensitive and dopa-resistant gait dysfunction in Parkinson's disease: selective responses to internal and external cues.

    PubMed

    Rochester, Lynn; Baker, Katherine; Nieuwboer, Alice; Burn, David

    2011-02-15

    Independence of certain gait characteristics from dopamine replacement therapies highlights its complex pathophysiology in Parkinson's disease (PD). We explored the effect of two different cue strategies on gait characteristics in relation to their response to dopaminergic medications. Fifty people with PD (age 69.22 ± 6.6 years) were studied. Participants walked with and without cues presented in a randomized order. Cue strategies were: (1) internal cue (attention to increase step length) and (2) external cue (auditory cue with instruction to take large step to the beat). Testing was carried out two times at home (on and off medication). Gait was measured using a Stride Analyzer (B&L Engineering). Gait outcomes were walking speed, stride length, step frequency, and coefficient of variation (CV) of stride time and double limb support duration (DLS). Walking speed, stride length, and stride time CV improved on dopaminergic medications, whereas step frequency and DLS CV did not. Internal and external cues increased stride time and walking speed (on and off dopaminergic medications). Only the external cue significantly improved stride time CV and DLS CV, whereas the internal cue had no effect (on and off dopaminergic medications). Internal and external cues selectively modify gait characteristics in relation to the type of gait disturbance and its dopa-responsiveness. Although internal (attention) and external cues target dopaminergic gait dysfunction (stride length), only external cues target stride to stride fluctuations in gait. Despite an overlap with dopaminergic pathways, external cues may effectively address nondopaminergic gait dysfunction and potentially increase mobility and reduce gait instability and falls. Copyright © 2010 Movement Disorder Society.

  18. Biologically inspired information theory: Adaptation through construction of external reality models by living systems.

    PubMed

    Nakajima, Toshiyuki

    2015-12-01

    Higher animals act in the world using their external reality models to cope with the uncertain environment. Organisms that have not developed such information-processing organs may also have external reality models built in the form of their biochemical, physiological, and behavioral structures, acquired by natural selection through successful models constructed internally. Organisms subject to illusions would fail to survive in the material universe. How can organisms, or living systems in general, determine the external reality from within? This paper starts with a phenomenological model, in which the self constitutes a reality model developed through the mental processing of phenomena. Then, the it-from-bit concept is formalized using a simple mathematical model. For this formalization, my previous work on an algorithmic process is employed to constitute symbols referring to the external reality, called the inverse causality, with additional improvements to the previous work. Finally, as an extension of this model, the cognizers system model is employed to describe the self as one of many material entities in a world, each of which acts as a subject by responding to the surrounding entities. This model is used to propose a conceptual framework of information theory that can deal with both the qualitative (semantic) and quantitative aspects of the information involved in biological processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Expansion Work without the External Pressure and Thermodynamics in Terms of Quasistatic Irreversible Processes

    ERIC Educational Resources Information Center

    Schmidt-Rohr, Klaus

    2014-01-01

    We demonstrate that the formula for irreversible expansion work in most chemical thermodynamics textbooks does not apply during the expansion process. Instead of the "external pressure" P[subscript ext], the pressure P[subscript sys,mb] on the piston or other moving boundary (hence the subscript mb), which is nearly equal to the system…

  20. External Technical Support for School Improvement: Critical Issues from the Chilean Experience

    ERIC Educational Resources Information Center

    Osses, Alejandra; Bellei, Cristián; Valenzuela, Juan Pablo

    2015-01-01

    To what extent school improvement processes can be initiated and sustained from the outside has been a relevant question for policy-makers seeking to increase quality in education. Since 2008, the Chilean Government is strongly promoting the use of external technical support (ETS) services to support school improvement processes, as part of the…

  1. Medical Devices; General Hospital and Personal Use Devices; Classification of the Image Processing Device for Estimation of External Blood Loss. Final order.

    PubMed

    2017-12-20

    The Food and Drug Administration (FDA or we) is classifying the image processing device for estimation of external blood loss into class II (special controls). The special controls that apply to the device type are identified in this order and will be part of the codified language for the image processing device for estimation of external blood loss' classification. We are taking this action because we have determined that classifying the device into class II (special controls) will provide a reasonable assurance of safety and effectiveness of the device. We believe this action will also enhance patients' access to beneficial innovative devices, in part by reducing regulatory burdens.

  2. Hypothesis for cognitive effects of transcranial direct current stimulation: Externally- and internally-directed cognition.

    PubMed

    Greenwood, Pamela M; Blumberg, Eric J; Scheldrup, Melissa R

    2018-03-01

    A comprehensive explanation is lacking for the broad array of cognitive effects modulated by transcranial direct current stimulation (tDCS). We advanced the testable hypothesis that tDCS to the default mode network (DMN) increases processing of goals and stored information at the expense of external events. We further hypothesized that tDCS to the dorsal attention network (DAN) increases processing of external events at the expense of goals and stored information. A literature search (PsychINFO) identified 42 empirical studies and 3 meta-analyses examining effects of prefrontal and/or parietal tDCS on tasks that selectively required external and/or internal processing. Most, though not all, of the studies that met our search criteria supported our hypothesis. Three meta-analyses supported our hypothesis. The hypothesis we advanced provides a framework for the design and interpretation of results in light of the role of large-scale intrinsic networks that govern attention. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Ionization of Rydberg atoms colliding with a metal surface

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sjakste, J.; Borisov, A. G.; Gauyacq, J. P.

    2006-04-15

    We report on a theoretical study of the ionization process of Xe* Rydberg atoms colliding with a metal surface, in the presence of an external electric field. The evolution of the Xe* outer electron is studied by a wave packet propagation approach, allowing to include all dynamical aspects of the collision, in particular nonadiabatic inter-Rydberg transitions. We investigate how the different Xe* Stark states formed in the external field couple together and ionize on the surface and how the different polarizations of the electronic cloud in the Xe* states are reflected in their ionization properties. We show that the presencemore » of the external electric field can significantly perturb the dynamics of the ionization process. Our results account for recent results from Dunning et al. [Nucl. Inst. Meth. B 203, 69 (2003)]. In particular, it is explained how the external electric field present in the experimental procedure of Dunning et al. leads to the apparent absence of a polarization effect in the ionization process.« less

  4. An explorative analysis of the recruitment of patients to a randomised controlled trial in adolescents with dental anxiety.

    PubMed

    Wide Boman, Ulla; Broberg, Anders G; Krekmanova, Larisa; Staberg, Marie; Svensson, Carina; Robertson, Agneta

    2014-01-01

    Randomised controlled trials (RCTs) are considered to provide the most reliable evidence on the efficacy of interventions. The aim of this study was to describe the recruitment process of an RCT study set up to evaluate a Cognitive Behavioural Therapy (CBT) intervention programme for adolescent patients with dental anxiety (DA). The participants were recruited from a consecutive sample of adolescent patients (12-19 yrs old) referred for DA to a specialised pediatric dentistry clinic. Age, gender, and reason for referral were recorded for the possible eligible patients as part of the drop-out analysis of the recruitment process. Participants were then randomized to the intervention (CBT integrated with dental treatment) or control (adapted dental treatment) condition. In the recruitment process, 138 possible eligible patients met inclusion criteria, of these 55 were enrolled, 44 declined participation and 39 patients were excluded.The patients enrolled in the RCT did not differ from the non-participants with regard to age, gender or cause of referral. As a result of difficulties in the recruitment process, the study period was extended. The considerable proportion of non-participants as evident from the recruitment process may pose a threat to the external validity of the clinical trial. From a clinical perspective, the reasons for the lack of motivation to participate in behavioural interventions and the failure to appear warrant further investigation.

  5. Spanking and children's externalizing behavior across the first decade of life: evidence for transactional processes.

    PubMed

    MacKenzie, Michael J; Nicklas, Eric; Brooks-Gunn, Jeanne; Waldfogel, Jane

    2015-03-01

    Despite a growing literature associating physical discipline with later child aggression, spanking remains a typical experience for American children. The directionality of the associations between aggression and spanking and their continuity over time has received less attention. This study examined the transactional associations between spanking and externalizing behavior across the first decade of life, examining not only how spanking relates to externalizing behavior leading up to the important transition to adolescence, but whether higher levels of externalizing lead to more spanking over time as well. We use data from the Fragile families and child well-being (FFCW) study to examine maternal spanking and children's behavior at ages 1, 3, 5, and 9 (N = 1,874; 48% girls). The FFCW is a longitudinal birth cohort study of children born between 1998 and 2000 in 20 medium to large US cities. A little over a quarter of this sample was spanked at age 1, and about half at age 3, 5, and 9. Estimates from a cross-lagged path model provided evidence of developmental continuity in both spanking and externalizing behavior, but results also highlighted important reciprocal processes taking hold early, with spanking influencing later externalizing behavior, which, in turn, predicted subsequent spanking. These bidirectional effects held across race/ethnicity and child's gender. The findings highlight the lasting effects of early spanking, both in influencing early child's behavior, and in affecting subsequent child's externalizing and parental spanking in a reciprocal manner. These amplifying transactional processes underscore the importance of early intervention before patterns may cascade across domains in the transition to adolescence.

  6. Salience of Somatosensory Stimulus Modulating External-to-Internal Orienting Attention.

    PubMed

    Peng, Jiaxin; Chan, Sam C C; Chau, Bolton K H; Yu, Qiuhua; Chan, Chetwyn C H

    2017-01-01

    Shifting between one's external and internal environments involves orienting attention. Studies on differentiating subprocesses associated with external-to-internal orienting attention are limited. This study aimed to reveal the characteristics of the disengagement, shifting and reengagement subprocesses by using somatosensory external stimuli and internally generated images. Study participants were to perceive nociceptive external stimuli (External Low (E L ) or External High (E H )) induced by electrical stimulations (50 ms) followed by mentally rehearsing learned subnociceptive images (Internal Low (I L ) and Internal High (I H )). Behavioral responses and EEG signals of the participants were recorded. The three significant components elicited were: fronto-central negativity (FCN; 128-180 ms), fronto-central P2 (200-260 ms), and central P3 (320-380 ms), which reflected the three subprocesses, respectively. Differences in the FCN and P2 amplitudes during the orienting to the subnociceptive images revealed only in the E H but not E L stimulus condition that are new findings. The results indicated that modulations of the disengagement and shifting processes only happened if the external nociceptive stimuli were of high salience and the external-to-internal incongruence was large. The reengaging process reflected from the amplitude of P3 correlated significantly with attenuation of the pain intensity felt from the external nociceptive stimuli. These findings suggested that the subprocesses underlying external-to-internal orienting attention serve different roles. Disengagement subprocess tends to be stimulus dependent, which is bottom-up in nature. Shifting and reengagement tend to be top-down subprocesses, which taps on cognitive control. This subprocess may account for the attenuation effects on perceived pain intensity after orienting attention.

  7. Salience of Somatosensory Stimulus Modulating External-to-Internal Orienting Attention

    PubMed Central

    Peng, Jiaxin; Chan, Sam C. C.; Chau, Bolton K. H.; Yu, Qiuhua; Chan, Chetwyn C. H.

    2017-01-01

    Shifting between one’s external and internal environments involves orienting attention. Studies on differentiating subprocesses associated with external-to-internal orienting attention are limited. This study aimed to reveal the characteristics of the disengagement, shifting and reengagement subprocesses by using somatosensory external stimuli and internally generated images. Study participants were to perceive nociceptive external stimuli (External Low (EL) or External High (EH)) induced by electrical stimulations (50 ms) followed by mentally rehearsing learned subnociceptive images (Internal Low (IL) and Internal High (IH)). Behavioral responses and EEG signals of the participants were recorded. The three significant components elicited were: fronto-central negativity (FCN; 128–180 ms), fronto-central P2 (200–260 ms), and central P3 (320–380 ms), which reflected the three subprocesses, respectively. Differences in the FCN and P2 amplitudes during the orienting to the subnociceptive images revealed only in the EH but not EL stimulus condition that are new findings. The results indicated that modulations of the disengagement and shifting processes only happened if the external nociceptive stimuli were of high salience and the external-to-internal incongruence was large. The reengaging process reflected from the amplitude of P3 correlated significantly with attenuation of the pain intensity felt from the external nociceptive stimuli. These findings suggested that the subprocesses underlying external-to-internal orienting attention serve different roles. Disengagement subprocess tends to be stimulus dependent, which is bottom-up in nature. Shifting and reengagement tend to be top-down subprocesses, which taps on cognitive control. This subprocess may account for the attenuation effects on perceived pain intensity after orienting attention. PMID:28970787

  8. Automated seismic detection of landslides at regional scales: a Random Forest based detection algorithm

    NASA Astrophysics Data System (ADS)

    Hibert, C.; Michéa, D.; Provost, F.; Malet, J. P.; Geertsema, M.

    2017-12-01

    Detection of landslide occurrences and measurement of their dynamics properties during run-out is a high research priority but a logistical and technical challenge. Seismology has started to help in several important ways. Taking advantage of the densification of global, regional and local networks of broadband seismic stations, recent advances now permit the seismic detection and location of landslides in near-real-time. This seismic detection could potentially greatly increase the spatio-temporal resolution at which we study landslides triggering, which is critical to better understand the influence of external forcings such as rainfalls and earthquakes. However, detecting automatically seismic signals generated by landslides still represents a challenge, especially for events with small mass. The low signal-to-noise ratio classically observed for landslide-generated seismic signals and the difficulty to discriminate these signals from those generated by regional earthquakes or anthropogenic and natural noises are some of the obstacles that have to be circumvented. We present a new method for automatically constructing instrumental landslide catalogues from continuous seismic data. We developed a robust and versatile solution, which can be implemented in any context where a seismic detection of landslides or other mass movements is relevant. The method is based on a spectral detection of the seismic signals and the identification of the sources with a Random Forest machine learning algorithm. The spectral detection allows detecting signals with low signal-to-noise ratio, while the Random Forest algorithm achieve a high rate of positive identification of the seismic signals generated by landslides and other seismic sources. The processing chain is implemented to work in a High Performance Computers centre which permits to explore years of continuous seismic data rapidly. We present here the preliminary results of the application of this processing chain for years of continuous seismic record by the Alaskan permanent seismic network and Hi-Climb trans-Himalayan seismic network. The processing chain we developed also opens the possibility for a near-real time seismic detection of landslides, in association with remote-sensing automated detection from Sentinel 2 images for example.

  9. Intra-fraction motion of the prostate is a random walk

    NASA Astrophysics Data System (ADS)

    Ballhausen, H.; Li, M.; Hegemann, N.-S.; Ganswindt, U.; Belka, C.

    2015-01-01

    A random walk model for intra-fraction motion has been proposed, where at each step the prostate moves a small amount from its current position in a random direction. Online tracking data from perineal ultrasound is used to validate or reject this model against alternatives. Intra-fraction motion of a prostate was recorded by 4D ultrasound (Elekta Clarity system) during 84 fractions of external beam radiotherapy of six patients. In total, the center of the prostate was tracked for 8 h in intervals of 4 s. Maximum likelihood model parameters were fitted to the data. The null hypothesis of a random walk was tested with the Dickey-Fuller test. The null hypothesis of stationarity was tested by the Kwiatkowski-Phillips-Schmidt-Shin test. The increase of variance in prostate position over time and the variability in motility between fractions were analyzed. Intra-fraction motion of the prostate was best described as a stochastic process with an auto-correlation coefficient of ρ = 0.92  ±  0.13. The random walk hypothesis (ρ = 1) could not be rejected (p = 0.27). The static noise hypothesis (ρ = 0) was rejected (p < 0.001). The Dickey-Fuller test rejected the null hypothesis ρ = 1 in 25% to 32% of cases. On average, the Kwiatkowski-Phillips-Schmidt-Shin test rejected the null hypothesis ρ = 0 with a probability of 93% to 96%. The variance in prostate position increased linearly over time (r2 = 0.9  ±  0.1). Variance kept increasing and did not settle at a maximum as would be expected from a stationary process. There was substantial variability in motility between fractions and patients with maximum aberrations from isocenter ranging from 0.5 mm to over 10 mm in one patient alone. In conclusion, evidence strongly suggests that intra-fraction motion of the prostate is a random walk and neither static (like inter-fraction setup errors) nor stationary (like a cyclic motion such as breathing, for example). The prostate tends to drift away from the isocenter during a fraction, and this variance increases with time, such that shorter fractions are beneficial to the problem of intra-fraction motion. As a consequence, fixed safety margins (which would over-compensate at the beginning and under-compensate at the end of a fraction) cannot optimally account for intra-fraction motion. Instead, online tracking and position correction on-the-fly should be considered as the preferred approach to counter intra-fraction motion.

  10. Brownian motion on random dynamical landscapes

    NASA Astrophysics Data System (ADS)

    Suñé Simon, Marc; Sancho, José María; Lindenberg, Katja

    2016-03-01

    We present a study of overdamped Brownian particles moving on a random landscape of dynamic and deformable obstacles (spatio-temporal disorder). The obstacles move randomly, assemble, and dissociate following their own dynamics. This landscape may account for a soft matter or liquid environment in which large obstacles, such as macromolecules and organelles in the cytoplasm of a living cell, or colloids or polymers in a liquid, move slowly leading to crowding effects. This representation also constitutes a novel approach to the macroscopic dynamics exhibited by active matter media. We present numerical results on the transport and diffusion properties of Brownian particles under this disorder biased by a constant external force. The landscape dynamics are characterized by a Gaussian spatio-temporal correlation, with fixed time and spatial scales, and controlled obstacle concentrations.

  11. How Do Question Writers Compose External Examination Questions? Question Writing as a Socio-Cognitive Process

    ERIC Educational Resources Information Center

    Johnson, Martin; Constantinou, Filio; Crisp, Victoria

    2017-01-01

    The focus of this research is on the practice of education examination question writing. Educational examinations are tests that are taken by candidates in schools or colleges but that are externally developed, administered and marked by an assessment organisation. Whilst the practice of writing external examination questions is ubiquitous,…

  12. Exposure to Externalizing Peers in Early Childhood: Homophily and Peer Contagion Processes.

    ERIC Educational Resources Information Center

    Hanish, Laura D.; Martin, Carol Lynn; Fabes, Richard A.; Leonard, Stacie; Herzog, Melissa

    2005-01-01

    Guided by a transactional model, we examined the predictors and effects of exposure to externalizing peers in a low-risk sample of preschoolers and kindergarteners. On the basis of daily observations of peer interactions, we calculated measures of total exposure to externalizing peers and measures of exposure to same- and other-sex externalizing…

  13. Externally Funded Research in Counselor Education: An Overview of the Process

    ERIC Educational Resources Information Center

    Villalba, Jose A.; Young, J. Scott

    2012-01-01

    "Publish or perish" is a phrase familiar to untenured and tenured faculty alike. In recent years, prominence has been placed on academicians to secure external funding for their research and training projects. The counselor education field has not been immune to this call for externally funded projects. This article includes strategies for seeking…

  14. Dynamic Processes in Network Goods: Modeling, Analysis and Applications

    ERIC Educational Resources Information Center

    Paothong, Arnut

    2013-01-01

    The network externality function plays a very important role in the study of economic network industries. Moreover, the consumer group dynamic interactions coupled with network externality concept is going to play a dominant role in the network goods in the 21st century. The existing literature is stemmed on a choice of externality function with…

  15. Scanning gate microscopy of quantum rings: effects of an external magnetic field and of charged defects.

    PubMed

    Pala, M G; Baltazar, S; Martins, F; Hackens, B; Sellier, H; Ouisse, T; Bayot, V; Huant, S

    2009-07-01

    We study scanning gate microscopy (SGM) in open quantum rings obtained from buried semiconductor InGaAs/InAlAs heterostructures. By performing a theoretical analysis based on the Keldysh-Green function approach we interpret the radial fringes observed in experiments as the effect of randomly distributed charged defects. We associate SGM conductance images with the local density of states (LDOS) of the system. We show that such an association cannot be made with the current density distribution. By varying an external magnetic field we are able to reproduce recursive quasi-classical orbits in LDOS and conductance images, which bear the same periodicity as the Aharonov-Bohm effect.

  16. Time delay and noise explaining the behaviour of the cell growth in fermentation process

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ayuobi, Tawfiqullah; Rosli, Norhayati; Bahar, Arifah

    2015-02-03

    This paper proposes to investigate the interplay between time delay and external noise in explaining the behaviour of the microbial growth in batch fermentation process. Time delay and noise are modelled jointly via stochastic delay differential equations (SDDEs). The typical behaviour of cell concentration in batch fermentation process under this model is investigated. Milstein scheme is applied for solving this model numerically. Simulation results illustrate the effects of time delay and external noise in explaining the lag and stationary phases, respectively for the cell growth of fermentation process.

  17. Time delay and noise explaining the behaviour of the cell growth in fermentation process

    NASA Astrophysics Data System (ADS)

    Ayuobi, Tawfiqullah; Rosli, Norhayati; Bahar, Arifah; Salleh, Madihah Md

    2015-02-01

    This paper proposes to investigate the interplay between time delay and external noise in explaining the behaviour of the microbial growth in batch fermentation process. Time delay and noise are modelled jointly via stochastic delay differential equations (SDDEs). The typical behaviour of cell concentration in batch fermentation process under this model is investigated. Milstein scheme is applied for solving this model numerically. Simulation results illustrate the effects of time delay and external noise in explaining the lag and stationary phases, respectively for the cell growth of fermentation process.

  18. Time-varying output performances of piezoelectric vibration energy harvesting under nonstationary random vibrations

    NASA Astrophysics Data System (ADS)

    Yoon, Heonjun; Kim, Miso; Park, Choon-Su; Youn, Byeng D.

    2018-01-01

    Piezoelectric vibration energy harvesting (PVEH) has received much attention as a potential solution that could ultimately realize self-powered wireless sensor networks. Since most ambient vibrations in nature are inherently random and nonstationary, the output performances of PVEH devices also randomly change with time. However, little attention has been paid to investigating the randomly time-varying electroelastic behaviors of PVEH systems both analytically and experimentally. The objective of this study is thus to make a step forward towards a deep understanding of the time-varying performances of PVEH devices under nonstationary random vibrations. Two typical cases of nonstationary random vibration signals are considered: (1) randomly-varying amplitude (amplitude modulation; AM) and (2) randomly-varying amplitude with randomly-varying instantaneous frequency (amplitude and frequency modulation; AM-FM). In both cases, this study pursues well-balanced correlations of analytical predictions and experimental observations to deduce the relationships between the time-varying output performances of the PVEH device and two primary input parameters, such as a central frequency and an external electrical resistance. We introduce three correlation metrics to quantitatively compare analytical prediction and experimental observation, including the normalized root mean square error, the correlation coefficient, and the weighted integrated factor. Analytical predictions are in an excellent agreement with experimental observations both mechanically and electrically. This study provides insightful guidelines for designing PVEH devices to reliably generate electric power under nonstationary random vibrations.

  19. Speed synchronization control for integrated automotive motor-transmission powertrain system with random delays

    NASA Astrophysics Data System (ADS)

    Zhu, Xiaoyuan; Zhang, Hui; Fang, Zongde

    2015-12-01

    This paper presents a robust speed synchronization controller design for an integrated motor-transmission powertrain system in which the driving motor and multi-gearbox are directly coupled. As the controller area network (CAN) is commonly used in the vehicle powertrain system, the possible network-induced random delays in both feedback and forward channel are considered and modeled by using two Markov chains in the controller design process. For the application perspective, the control law adopted here is a generalized proportional-integral (PI) control. By employing the system-augmentation technique, a delay-free stochastic closed-loop system is obtained and the generalized PI controller design problem is converted to a static output feedback (SOF) controller design problem. Since there are external disturbances involved in the closed-loop system, the energy-to-peak performance is considered to guarantee the robustness of the controller. And the controlled output is chosen as the speed synchronization error. To further improve the transient response of the closed-loop system, the pole placement is also employed in the energy-to-peak performance based speed synchronization control. The mode-dependent control gains are obtained by using an iterative linear matrix inequality (LMI) algorithm. Simulation results show the effectiveness of the proposed control approach.

  20. Quantifying the degree of persistence in random amoeboid motion based on the Hurst exponent of fractional Brownian motion.

    PubMed

    Makarava, Natallia; Menz, Stephan; Theves, Matthias; Huisinga, Wilhelm; Beta, Carsten; Holschneider, Matthias

    2014-10-01

    Amoebae explore their environment in a random way, unless external cues like, e.g., nutrients, bias their motion. Even in the absence of cues, however, experimental cell tracks show some degree of persistence. In this paper, we analyzed individual cell tracks in the framework of a linear mixed effects model, where each track is modeled by a fractional Brownian motion, i.e., a Gaussian process exhibiting a long-term correlation structure superposed on a linear trend. The degree of persistence was quantified by the Hurst exponent of fractional Brownian motion. Our analysis of experimental cell tracks of the amoeba Dictyostelium discoideum showed a persistent movement for the majority of tracks. Employing a sliding window approach, we estimated the variations of the Hurst exponent over time, which allowed us to identify points in time, where the correlation structure was distorted ("outliers"). Coarse graining of track data via down-sampling allowed us to identify the dependence of persistence on the spatial scale. While one would expect the (mode of the) Hurst exponent to be constant on different temporal scales due to the self-similarity property of fractional Brownian motion, we observed a trend towards stronger persistence for the down-sampled cell tracks indicating stronger persistence on larger time scales.

  1. Non-Brownian dynamics and strategy of amoeboid cell locomotion.

    PubMed

    Nishimura, Shin I; Ueda, Masahiro; Sasai, Masaki

    2012-04-01

    Amoeboid cells such as Dictyostelium discoideum and Madin-Darby canine kidney cells show the non-Brownian dynamics of migration characterized by the superdiffusive increase of mean-squared displacement. In order to elucidate the physical mechanism of this non-Brownian dynamics, a computational model is developed which highlights a group of inhibitory molecules for actin polymerization. Based on this model, we propose a hypothesis that inhibitory molecules are sent backward in the moving cell to accumulate at the rear of cell. The accumulated inhibitory molecules at the rear further promote cell locomotion to form a slow positive feedback loop of the whole-cell scale. The persistent straightforward migration is stabilized with this feedback mechanism, but the fluctuation in the distribution of inhibitory molecules and the cell shape deformation concurrently interrupt the persistent motion to turn the cell into a new direction. A sequence of switching behaviors between persistent motions and random turns gives rise to the superdiffusive migration in the absence of the external guidance signal. In the complex environment with obstacles, this combined process of persistent motions and random turns drives the simulated amoebae to solve the maze problem in a highly efficient way, which suggests the biological advantage for cells to bear the non-Brownian dynamics.

  2. Critical Evaluation of Human Oral Bioavailability for Pharmaceutical Drugs by Using Various Cheminformatics Approaches

    PubMed Central

    Kim, Marlene; Sedykh, Alexander; Chakravarti, Suman K.; Saiakhov, Roustem D.; Zhu, Hao

    2014-01-01

    Purpose Oral bioavailability (%F) is a key factor that determines the fate of a new drug in clinical trials. Traditionally, %F is measured using costly and time -consuming experimental tests. Developing computational models to evaluate the %F of new drugs before they are synthesized would be beneficial in the drug discovery process. Methods We employed Combinatorial Quantitative Structure-Activity Relationship approach to develop several computational %F models. We compiled a %F dataset of 995 drugs from public sources. After generating chemical descriptors for each compound, we used random forest, support vector machine, k nearest neighbor, and CASE Ultra to develop the relevant QSAR models. The resulting models were validated using five-fold cross-validation. Results The external predictivity of %F values was poor (R2=0.28, n=995, MAE=24), but was improved (R2=0.40, n=362, MAE=21) by filtering unreliable predictions that had a high probability of interacting with MDR1 and MRP2 transporters. Furthermore, classifying the compounds according to the %F values (%F<50% as “low”, %F≥50% as ‘high”) and developing category QSAR models resulted in an external accuracy of 76%. Conclusions In this study, we developed predictive %F QSAR models that could be used to evaluate new drug compounds, and integrating drug-transporter interactions data greatly benefits the resulting models. PMID:24306326

  3. One-Way Multishape-Memory Effect and Tunable Two-Way Shape Memory Effect of Ionomer Poly(ethylene-co-methacrylic acid).

    PubMed

    Lu, Lu; Li, Guoqiang

    2016-06-15

    Reversible elongation by cooling and contraction by heating, without the need for repeated programming, is well-known as the two-way shape-memory effect (2W-SME). This behavior is contrary to the common physics-contraction when cooling and expansion when heating. Materials with such behavior may find many applications in real life, such as self-sufficient grippers, fastening devices, optical gratings, soft actuators, and sealant. Here, it is shown that ionomer Surlyn 8940, a 50-year old polymer, exhibits both one-way multishape-memory effects and tunable two-way reversible actuation. The required external tensile stress to trigger the tunable 2W-SME is very low when randomly jumping the temperatures within the melting transition window. With a proper one-time programming, "true" 2W-SME (i.e., 2W-SME without the need for an external tensile load) is also achieved. A long training process is not needed to trigger the tunable 2W-SME. Instead, a proper one-time tensile programming is sufficient to trigger repeated and tunable 2W-SME. Because the 2W-SME of the ionomer Surlyn is driven by the thermally reversible network, here crystallization and melting transitions of the semicrystalline poly(ethylene-co-methacrylic acid), it is believed that a class of thermally reversible polymers should also exhibit tunable 2W-SMEs.

  4. Mentalization-based treatment in groups for adolescents with borderline personality disorder (BPD) or subthreshold BPD versus treatment as usual (M-GAB): study protocol for a randomized controlled trial.

    PubMed

    Beck, Emma; Bo, Sune; Gondan, Matthias; Poulsen, Stig; Pedersen, Liselotte; Pedersen, Jesper; Simonsen, Erik

    2016-07-12

    Evidence-based outpatient psychotherapeutic programs are first-line treatment of borderline personality disorder (BPD). Early and effective treatment of BPD is crucial to the prevention of its individual, psychosocial, and economic consequences. However, in spite of recent advantages in diagnosing adolescent BPD, there is a lack of cost-effective evidence-based treatment programs for adolescents. Mentalization-based treatment is an evidence-based program for BPD, originally developed for adults. We will investigate whether a specifically designed mentalization-based treatment in groups is an efficacious treatment for adolescents with BPD or subthreshold BPD compared to treatment as usual. The trial is a four-center, two-armed, parallel-group, assessor-blinded randomized clinical superiority trial. One hundred twelve patients aged 14 to 17 referred to Child and Adolescent Psychiatric Clinics in Region Zealand are randomized to 1 year of either mentalization-based treatment in groups or treatment as usual. Patients will be included if they meet at least four DSM-5 criteria for BPD. The primary outcome is self-reported borderline features at discharge. Secondary outcomes will include self-harm, depression, BPD criteria, externalizing and internalizing symptoms, and social functioning, together with parental reports on borderline features, externalizing and internalizing symptoms. Measures of attachment and mentalization will be included as mediational variables. Follow-up assessment will take place at 3 and 12 months after end of treatment. This is the first randomized controlled trial to test the efficacy of a group-based mentalization-based treatment for adolescents with BPD or subthreshold BPD. If the results confirm our hypothesis, this trial will add to the treatment options of cost-effective treatment of adolescent BPD. Clinicaltrials.gov NCT02068326 , February 19, 2014.

  5. Voice quality after treatment of early vocal cord cancer: a randomized trial comparing laser surgery with radiation therapy.

    PubMed

    Aaltonen, Leena-Maija; Rautiainen, Noora; Sellman, Jaana; Saarilahti, Kauko; Mäkitie, Antti; Rihkanen, Heikki; Laranne, Jussi; Kleemola, Leenamaija; Wigren, Tuija; Sala, Eeva; Lindholm, Paula; Grenman, Reidar; Joensuu, Heikki

    2014-10-01

    Early laryngeal cancer is usually treated with either transoral laser surgery or radiation therapy. The quality of voice achieved with these treatments has not been compared in a randomized trial. Male patients with carcinoma limited to 1 mobile vocal cord (T1aN0M0) were randomly assigned to receive either laser surgery (n=32) or external beam radiation therapy (n=28). Surgery consisted of tumor excision with a CO2 laser with the patient under general anaesthesia. External beam radiation therapy to the larynx was delivered to a cumulative dose of 66 Gy in 2-Gy daily fractions over 6.5 weeks. Voice quality was assessed at baseline and 6 and 24 months after treatment. The main outcome measures were expert-rated voice quality on a grade, roughness, breathiness, asthenia, and strain (GRBAS) scale, videolaryngostroboscopic findings, and the patients' self-rated voice quality and its impact on activities of daily living. Overall voice quality between the groups was rated similar, but voice was more breathy and the glottal gap was wider in patients treated with laser surgery than in those who received radiation therapy. Patients treated with radiation therapy reported less hoarseness-related inconvenience in daily living 2 years after treatment. Three patients in each group had local cancer recurrence within 2 years from randomization. Radiation therapy may be the treatment of choice for patients whose requirements for voice quality are demanding. Overall voice quality was similar in both treatment groups, however, indicating a need for careful consideration of patient-related factors in the choice of a treatment option. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. External validity of randomized controlled trials in older adults, a systematic review.

    PubMed

    van Deudekom, Floor J; Postmus, Iris; van der Ham, Danielle J; Pothof, Alexander B; Broekhuizen, Karen; Blauw, Gerard J; Mooijaart, Simon P

    2017-01-01

    To critically assess the external validity of randomized controlled trials (RCTs) it is important to know what older adults have been enrolled in the trials. The aim of this systematic review is to study what proportion of trials specifically designed for older patients report on somatic status, physical and mental functioning, social environment and frailty in the patient characteristics. PubMed was searched for articles published in 2012 and only RCTs were included. Articles were further excluded if not conducted with humans or only secondary analyses were reported. A random sample of 10% was drawn. The current review analyzed this random sample and further selected trials when the reported mean age was ≥ 60 years. We extracted geriatric assessments from the population descriptives or the in- and exclusion criteria. In total 1396 trials were analyzed and 300 trials included. The median of the reported mean age was 66 (IQR 63-70) and the median percentage of men in the trials was 60 (IQR 45-72). In 34% of the RCTs specifically designed for older patients somatic status, physical and mental functioning, social environment or frailty were reported in the population descriptives or the in- and exclusion criteria. Physical and mental functioning was reported most frequently (22% and 14%). When selecting RCTs on a mean age of 70 or 80 years the report of geriatric assessments in the patient characteristics was 46% and 85% respectively but represent only 5% and 1% of the trials. Somatic status, physical and mental functioning, social environment and frailty are underreported even in RCTs specifically designed for older patients published in 2012. Therefore, it is unclear for clinicians to which older patients the results can be applied. We recommend systematic to transparently report these relevant characteristics of older participants included in RCTs.

  7. A Smartphone Application to Reduce the Time to Automated External Defibrillator Delivery After a Witnessed Out-of-Hospital Cardiac Arrest: A Randomized Simulation-Based Study.

    PubMed

    Hatakeyama, Toshihiro; Nishiyama, Chika; Shimamoto, Tomonari; Kiyohara, Kosuke; Kiguchi, Takeyuki; Chida, Izumi; Izawa, Junichi; Matsuyama, Tasuku; Kitamura, Tetsuhisa; Kawamura, Takashi; Iwami, Taku

    2018-04-13

    We developed a new smartphone application to deliver an automated external defibrillator (AED) to out-of-hospital cardiac arrest scene. The aim of this study was to evaluate whether an AED could be delivered earlier with or without an application in a simulated randomized controlled trial. Participants, who were asked to work as bystanders, were randomly assigned to either an application group or control group and were asked to bring an AED in both groups. The bystanders in the application group sent a signal notification using the application to two responders, who were stationed within 200 meters of the arrest scene, to carry an AED. The primary outcome was the AED delivery time by either the bystander or his/her responder. In total, 61 bystanders were eligible and randomized to either the application group (32) or the control group (29). The 52 with time data were available and analyzed. The AED delivery time by either the bystander or his/her responder was significantly shorter in the application group than in the control group [133.6 (44.4) seconds vs. 202.2 (122.2) seconds, P = 0.01]. In this simulation-based trial, AED delivery time was shortened by our newly developed smartphone application for the bystander to ask nearby responders to find and bring an AED to the cardiac arrest scene (UMIN-Clinical Trials Registry 000016506).This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.

  8. Voice Quality After Treatment of Early Vocal Cord Cancer: A Randomized Trial Comparing Laser Surgery With Radiation Therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aaltonen, Leena-Maija, E-mail: leena-maija.aaltonen@hus.fi; Rautiainen, Noora; Sellman, Jaana

    Objective: Early laryngeal cancer is usually treated with either transoral laser surgery or radiation therapy. The quality of voice achieved with these treatments has not been compared in a randomized trial. Methods and Materials: Male patients with carcinoma limited to 1 mobile vocal cord (T1aN0M0) were randomly assigned to receive either laser surgery (n=32) or external beam radiation therapy (n=28). Surgery consisted of tumor excision with a CO{sub 2} laser with the patient under general anaesthesia. External beam radiation therapy to the larynx was delivered to a cumulative dose of 66 Gy in 2-Gy daily fractions over 6.5 weeks. Voice quality wasmore » assessed at baseline and 6 and 24 months after treatment. The main outcome measures were expert-rated voice quality on a grade, roughness, breathiness, asthenia, and strain (GRBAS) scale, videolaryngostroboscopic findings, and the patients' self-rated voice quality and its impact on activities of daily living. Results: Overall voice quality between the groups was rated similar, but voice was more breathy and the glottal gap was wider in patients treated with laser surgery than in those who received radiation therapy. Patients treated with radiation therapy reported less hoarseness-related inconvenience in daily living 2 years after treatment. Three patients in each group had local cancer recurrence within 2 years from randomization. Conclusions: Radiation therapy may be the treatment of choice for patients whose requirements for voice quality are demanding. Overall voice quality was similar in both treatment groups, however, indicating a need for careful consideration of patient-related factors in the choice of a treatment option.« less

  9. Randomized, controlled, two-arm, interventional, multicenter study on risk-adapted damage control orthopedic surgery of femur shaft fractures in multiple-trauma patients.

    PubMed

    Rixen, Dieter; Steinhausen, Eva; Sauerland, Stefan; Lefering, Rolf; Maegele, Marc G; Bouillon, Bertil; Grass, Guido; Neugebauer, Edmund A M

    2016-01-25

    Long bone fractures, particularly of the femur, are common in multiple-trauma patients, but their optimal management has not yet been determined. Although a trend exists toward the concept of "damage control orthopedics" (DCO), current literature is inconclusive. Thus, a need exists for a more specific controlled clinical study. The primary objective of this study was to clarify whether a risk-adapted procedure for treating femoral fractures, as opposed to an early definitive treatment strategy, leads to an improved outcome (morbidity and mortality). The study was designed as a randomized controlled multicenter study. Multiple-trauma patients with femur shaft fractures and a calculated probability of death of 20 to 60 % were randomized to either temporary fracture fixation with external fixation and defined secondary definitive treatment (DCO) or primary reamed nailing (early total care). The primary objective was to reduce the extent of organ failure as measured by the maximum sepsis-related organ failure assessment (SOFA) score. Thirty-four patients were randomized to two groups of 17 patients each. Both groups were comparable regarding sex, age, injury severity score, Glasgow Coma Scale, prothrombin time, base excess, calculated probability of death, and other physiologic variables. The maximum SOFA score was comparable (nonsignificant) between the groups. Regarding the secondary endpoints, the patients with external fixation required a significantly longer ventilation period (p = 0.049) and stayed on the intensive care significantly longer (p = 0.037), whereas the in-hospital length of stay was balanced for both groups. Unfortunately, the study had to be terminated prior to reaching the anticipated sample size because of unexpected low patient recruitment. Thus, the results of this randomized study reflect the ambivalence in the literature. No advantage of the damage control concept could be detected in the treatment of femur fractures in multiple-trauma patients. The necessity for scientific evaluation of this clinically relevant question remains. Current Controlled Trials ISRCTN10321620 Date assigned: 9 February 2007.

  10. Fast Track Randomized Controlled Trial to Prevent Externalizing Psychiatric Disorders: Findings from Grades 3 to 9

    ERIC Educational Resources Information Center

    Journal of the American Academy of Child & Adolescent Psychiatry, 2007

    2007-01-01

    Objective: This study tests the efficacy of the Fast Track Program in preventing antisocial behavior and psychiatric disorders among groups varying in initial risk. Method: Schools within four sites (Durham, NC; Nashville, TN; Seattle, WA; and rural central Pennsylvania) were selected as high-risk institutions based on neighborhood crime and…

  11. 78 FR 63479 - Meta-Analyses of Randomized Controlled Clinical Trials (RCTs) for the Evaluation of Risk To...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-24

    ... methodological issues that arise in the use of meta-analyses to evaluate safety risks, followed by a discussion... design, conduct and use of meta-analysis. Although many external stakeholders conduct meta-analyses, FDA... meeting. FDA expects that this meeting will build upon prior stakeholder feedback on the design, conduct...

  12. How Generalizable Is Your Experiment? An Index for Comparing Samples and Populations

    ERIC Educational Resources Information Center

    Tipton, Elizabeth

    2013-01-01

    Recent research on the design of social experiments has highlighted the effects of different design choices on research findings. Since experiments rarely collect their samples using random selection, in order to address these external validity problems and design choices, recent research has focused on two areas. The first area is on methods for…

  13. Dimensions of Oppositional Defiant Disorder in 3-Year-Old Preschoolers

    ERIC Educational Resources Information Center

    Ezpeleta, Lourdes; Granero, Roser; de la Osa, Nuria; Penelo, Eva; Domenech, Josep M.

    2012-01-01

    Background: To test the factor structure of oppositional defiant disorder (ODD) symptoms and to study the relationships between the proposed dimensions and external variables in a community sample of preschool children. Method: A sample of 1,341 3-year-old preschoolers was randomly selected and screened for a double-phase design. In total, 622…

  14. The Role of Preschool Teacher-Child Interactions in Academic Adjustment: An Intervention Study with Playing-2-Gether

    ERIC Educational Resources Information Center

    Van Craeyevelt, Sanne; Verschueren, Karine; Vancraeyveldt, Caroline; Wouters, Sofie; Colpin, Hilde

    2017-01-01

    Background: Social relationships can serve as important risk or protective factors for child development in general, and academic adjustment in particular. Aims: This study investigated the role of teacher-child interactions in academic adjustment among preschool boys at risk of externalizing behaviour, using a randomized controlled trial study…

  15. Single-Case Experimental Designs for the Evaluation of Treatments for Self-Injurious and Suicidal Behaviors

    ERIC Educational Resources Information Center

    Rizvi, Shireen L.; Nock, Matthew K.

    2008-01-01

    Single-case experimental designs (SCEDs) provide a time- and cost-effective alternative to randomized clinical trials and offer significant advantages in terms of internal and external validity. A brief history and primer on SCEDs is provided, specifically for use in suicide intervention research. Various SCED methodologies, such as AB, ABAB,…

  16. A Cognitive Framework for Understanding and Improving Interference Resolution in the Brain

    PubMed Central

    Mishra, Jyoti; Anguera, Joaquin A.; Ziegler, David A.; Gazzaley, Adam

    2014-01-01

    All of us are familiar with the negative impact of interference on achieving our task goals. We are referring to interference by information, which either impinges on our senses from an external environmental source or is internally generated by our thoughts. Informed by more than a decade of research on the cognitive and neural processing of interference, we have developed a framework for understanding how interference impacts our neural systems and especially how it is regulated and suppressed during efficient on-task performance. Importantly, externally and internally generated interferences have distinct neural signatures, and further, distinct neural processing emerges depending on whether individuals must ignore and suppress the interference, as for distractions, or engage with them in a secondary task, as during multitasking. Here, we elaborate on this cognitive framework and how it changes throughout the human lifespan, focusing mostly on research evidence from younger adults and comparing these findings to data from older adults, children, and cognitively impaired populations. With insights gleaned from our growing understanding, we then describe three novel translational efforts in our lab directed at improving distinct aspects of interference resolution using cognitive training. Critically, these training approaches were specifically developed to target improved interference resolution based on neuroplasticity principles and have shown much success in randomized controlled first version evaluations in healthy aging. Our results show not only on-task training improvements but also robust generalization of benefit to other cognitive control abilities. This research showcases how an in-depth understanding of neural mechanisms can then inform the development of effective deficit-targeted interventions, which can in turn benefit both healthy and cognitively impaired populations. PMID:24309262

  17. The effect of phenotypic traits and external cues on natal dispersal movements.

    PubMed

    Delgado, María del Mar; Penteriani, Vincenzo; Revilla, Eloy; Nams, Vilis O

    2010-05-01

    1. Natal dispersal has the potential to affect most ecological and evolutionary processes. However, despite its importance, this complex ecological process still represents a significant gap in our understanding of animal ecology due to both the lack of empirical data and the intrinsic complexity of dispersal dynamics. 2. By studying natal dispersal of 74 radiotagged juvenile eagle owls Bubo bubo (Linnaeus), in both the wandering and the settlement phases, we empirically addressed the complex interactions by which individual phenotypic traits and external cues jointly shape individual heterogeneity through the different phases of dispersal, both at nightly and weekly temporal scales. 3. Owls in poorer physical conditions travelled shorter total distances during the wandering phase, describing straighter paths and moving slower, especially when crossing heterogeneous habitats. In general, the owls in worse condition started dispersal later and took longer times to find further settlement areas. Net distances were also sex biased, with females settling at further distances. Dispersing individuals did not seem to explore wandering and settlement areas by using a search image of their natal surroundings. Eagle owls showed a heterogeneous pattern of patch occupancy, where few patches were highly visited by different owls whereas the majority were visited by just one individual. During dispersal, the routes followed by owls were an intermediate solution between optimized and randomized ones. Finally, dispersal direction had a marked directionality, largely influenced by dominant winds. These results suggest an asymmetric and anisotropic dispersal pattern, where not only the number of patches but also their functions can affect population viability. 4. The combination of the information coming from the relationships among a large set of factors acting and integrating at different spatial and temporal scales, under the perspective of heterogeneous life histories, are a fruitful ground for future understanding of natal dispersal.

  18. Fostering Self-Regulated Learning in a Blended Environment Using Group Awareness and Peer Assistance as External Scaffolds

    ERIC Educational Resources Information Center

    Lin, J-W.; Lai, Y-C.; Lai, Y-C.; Chang, L-C.

    2016-01-01

    Most systems for training self-regulated learning (SRL) behaviour focus on the provision of a learner-centred environment. Such systems repeat the training process and place learners alone to experience that process iteratively. According to the relevant literature, external scaffolds are more promising for effective SRL training. In this work,…

  19. Improvement of light penetration based silkworm gender identification with confined regions of interest

    NASA Astrophysics Data System (ADS)

    Kamtongdee, Chakkrit; Sumriddetchkajorn, Sarun; Sa-ngiamsak, Chiranut

    2013-06-01

    Based on our previous work on light penetration-based silkworm gender identification, we find that unwanted optical noises scattering from the surrounding area near the silkworm pupa and the transparent support are sometimes analyzed and misinterpreted leading to incorrect silkworm gender identification. To alleviate this issue, we place a small rectangular hole on a transparent support so that it not only helps the user precisely place the silkworm pupa but also functions as a region of interest (ROI) for blocking unwanted optical noises and for roughly locating the abdomen region in the image for ease of image processing. Apart from the external ROI, we also assign a smaller ROI inside the image in order to remove strong scattering light from all edges of the external ROI and at the same time speed up our image processing operations. With only the external ROI in function, our experiment shows a measured 86% total accuracy in identifying gender of 120 silkworm pupae with a measured average processing time of 38 ms. Combining the external ROI and the image ROI together revamps the total accuracy in identifying the silkworm gender to 95% with a measured faster 18 ms processing time.

  20. Inherited and Environmental Influences on a Childhood Co-Occurring Symptom Phenotype: Evidence From an Adoption Study

    PubMed Central

    Roos, Leslie E.; Fisher, Philip A.; Shaw, Daniel S.; Kim, Hyoun K.; Neiderhiser, Jenae M.; Reiss, David; Natsuaki, Misaki N.; Leve, Leslie D.

    2015-01-01

    Risk factors for the childhood development of co-occurring internalizing and externalizing symptoms are not well understood, despite a high prevalence and poor clinical outcomes associated with this co-occurring phenotype. We examined inherited and environmental risk factors for co-occurring symptoms in a sample of children adopted at birth and their birth mothers and adoptive mothers (N = 293). Inherited risk factors (i.e., birth mothers’ processing speed and internalizing symptoms) and environmental risk factors (i.e., adoptive mothers’ processing speed, internalizing symptoms, and uninvolved parenting) were examined as predictors for the development of internalizing-only, externalizing-only, or co-occurring symptoms using structural equation modeling. Results suggested a unique pattern of predictive factors for the co-occurring phenotype, with risk conferred by adoptive mothers’ uninvolved parenting, birth mothers’ slower processing speed, and the birth mothers’ slower processing speed in tandem with adoptive mothers’ higher internalizing symptoms. Additional analyses indicated that when co-occurring-symptom children were incorporated into internalizing and externalizing symptom groups, differential risk factors for externalizing and internalizing symptoms emerged. The findings suggest that spurious results may be found when children with co-occurring symptoms are not examined as a unique phenotypic group. PMID:25851306

  1. Inherited and environmental influences on a childhood co-occurring symptom phenotype: Evidence from an adoption study.

    PubMed

    Roos, Leslie E; Fisher, Philip A; Shaw, Daniel S; Kim, Hyoun K; Neiderhiser, Jenae M; Reiss, David; Natsuaki, Misake N; Leve, Leslie D

    2016-02-01

    Risk factors for the childhood development of co-occurring internalizing and externalizing symptoms are not well understood, despite a high prevalence and poor clinical outcomes associated with this co-occurring phenotype. We examined inherited and environmental risk factors for co-occurring symptoms in a sample of children adopted at birth and their birth mothers and adoptive mothers (N = 293). Inherited risk factors (i.e., birth mothers' processing speed and internalizing symptoms) and environmental risk factors (i.e., adoptive mothers' processing speed, internalizing symptoms, and uninvolved parenting) were examined as predictors for the development of internalizing-only, externalizing-only, or co-occurring symptoms using structural equation modeling. Results suggested a unique pattern of predictive factors for the co-occurring phenotype, with risk conferred by adoptive mothers' uninvolved parenting, birth mothers' slower processing speed, and the birth mothers' slower processing speed in tandem with adoptive mothers' higher internalizing symptoms. Additional analyses indicated that when co-occurring-symptom children were incorporated into internalizing and externalizing symptom groups, differential risk factors for externalizing and internalizing symptoms emerged. The findings suggest that spurious results may be found when children with co-occurring symptoms are not examined as a unique phenotypic group.

  2. Effects of flow restoration on mussel growth in a Wild and Scenic North American River

    PubMed Central

    2013-01-01

    Background Freshwater mussels remain among the most imperiled species in North America due primarily to habitat loss or degradation. Understanding how mussels respond to habitat changes can improve conservation efforts. Mussels deposit rings in their shell in which age and growth information can be read, and thus used to evaluate how mussels respond to changes in habitat. However, discrepancies between methodological approaches to obtain life history information from growth rings has led to considerable uncertainty regarding the life history characteristics of many mussel species. In this study we compared two processing methods, internal and external ring examination, to obtain age and growth information of two populations of mussels in the St. Croix River, MN, and evaluated how mussel growth responded to changes in the operation of a hydroelectric dam. Results External ring counts consistently underestimated internal ring counts by 4 years. Despite this difference, internal and external growth patterns were consistent. In 2000, the hydroelectric dam switched from operating on a peaking schedule to run-of-the-river/partial peaking. Growth patterns between an upstream and downstream site of the dam were similar both before and after the change in operation. At the downstream site, however, older mussels had higher growth rates after the change in operation than the same sized mussels collected before the change. Conclusions Because growth patterns between internal and external processing methods were consistent, we suggest that external processing is an effective method to obtain growth information despite providing inaccurate age information. External processing is advantageous over internal processing due to its non-destructive nature. Applying this information to analyze the influence of the operation change in the hydroelectric dam, we suggest that changing to run-of-the-river/partial peaking operation has benefited the growth of older mussels below the dam. PMID:23452382

  3. Daily precipitation grids for Austria since 1961—development and evaluation of a spatial dataset for hydroclimatic monitoring and modelling

    NASA Astrophysics Data System (ADS)

    Hiebl, Johann; Frei, Christoph

    2018-04-01

    Spatial precipitation datasets that are long-term consistent, highly resolved and extend over several decades are an increasingly popular basis for modelling and monitoring environmental processes and planning tasks in hydrology, agriculture, energy resources management, etc. Here, we present a grid dataset of daily precipitation for Austria meant to promote such applications. It has a grid spacing of 1 km, extends back till 1961 and is continuously updated. It is constructed with the classical two-tier analysis, involving separate interpolations for mean monthly precipitation and daily relative anomalies. The former was accomplished by kriging with topographic predictors as external drift utilising 1249 stations. The latter is based on angular distance weighting and uses 523 stations. The input station network was kept largely stationary over time to avoid artefacts on long-term consistency. Example cases suggest that the new analysis is at least as plausible as previously existing datasets. Cross-validation and comparison against experimental high-resolution observations (WegenerNet) suggest that the accuracy of the dataset depends on interpretation. Users interpreting grid point values as point estimates must expect systematic overestimates for light and underestimates for heavy precipitation as well as substantial random errors. Grid point estimates are typically within a factor of 1.5 from in situ observations. Interpreting grid point values as area mean values, conditional biases are reduced and the magnitude of random errors is considerably smaller. Together with a similar dataset of temperature, the new dataset (SPARTACUS) is an interesting basis for modelling environmental processes, studying climate change impacts and monitoring the climate of Austria.

  4. Changes in spinal reflex excitability associated with motor sequence learning.

    PubMed

    Lungu, Ovidiu; Frigon, Alain; Piché, Mathieu; Rainville, Pierre; Rossignol, Serge; Doyon, Julien

    2010-05-01

    There is ample evidence that motor sequence learning is mediated by changes in brain activity. Yet the question of whether this form of learning elicits changes detectable at the spinal cord level has not been addressed. To date, studies in humans have revealed that spinal reflex activity may be altered during the acquisition of various motor skills, but a link between motor sequence learning and changes in spinal excitability has not been demonstrated. To address this issue, we studied the modulation of H-reflex amplitude evoked in the flexor carpi radialis muscle of 14 healthy individuals between blocks of movements that involved the implicit acquisition of a sequence versus other movements that did not require learning. Each participant performed the task in three conditions: "sequence"-externally triggered, repeating and sequential movements, "random"-similar movements, but performed in an arbitrary order, and "simple"- involving alternating movements in a left-right or up-down direction only. When controlling for background muscular activity, H-reflex amplitude was significantly more reduced in the sequence (43.8 +/- 1.47%. mean +/- SE) compared with the random (38.2 +/- 1.60%) and simple (31.5 +/- 1.82%) conditions, while the M-response was not different across conditions. Furthermore, H-reflex changes were observed from the beginning of the learning process up to when subjects reached asymptotic performance on the motor task. Changes also persisted for >60 s after motor activity ceased. Such findings suggest that the excitability in some spinal reflex circuits is altered during the implicit learning process of a new motor sequence.

  5. Evaluation of programs to improve complementary feeding in infants and young children.

    PubMed

    Frongillo, Edward A

    2017-10-01

    Evaluation of complementary feeding programs is needed to enhance knowledge on what works, to document responsible use of resources, and for advocacy. Evaluation is done during program conceptualization and design, implementation, and determination of effectiveness. This paper explains the role of evaluation in the advancement of complementary feeding programs, presenting concepts and methods and illustrating them through examples. Planning and investments for evaluations should occur from the beginning of the project life cycle. Essential to evaluation is articulation of a program theory on how change would occur and what program actions are required for change. Analysis of program impact pathways makes explicit the dynamic connections in the program theory and accounts for contextual factors that could influence program effectiveness. Evaluating implementation functioning is done through addressing questions about needs, coverage, provision, and utilization using information obtained from process evaluation, operations research, and monitoring. Evaluating effectiveness is done through assessing impact, efficiency, coverage, process, and causality. Plausibility designs ask whether the program seemed to have an effect above and beyond external influences, often using a nonrandomized control group and baseline and end line measures. Probability designs ask whether there was an effect using a randomized control group. Evaluations may not be able to use randomization, particularly for programs implemented at a large scale. Plausibility designs, innovative designs, or innovative combinations of designs sometimes are best able to provide useful information. Further work is needed to develop practical designs for evaluation of large-scale country programs on complementary feeding. © 2017 John Wiley & Sons Ltd.

  6. Characterizing the Anomalous Cognition-Emotion Interactions in Externalizing

    PubMed Central

    Baskin-Sommers, Arielle R.; Curtin, John J.; Larson, Christine L.; Stout, Daniel; Kiehl, Kent A.; Newman, Joseph P.

    2012-01-01

    Externalizing traits are characterized by exaggerated emotional (e.g., frustration, anger) and behavioral (e.g., drug seeking, reactive aggression) reactions to motivationally-significant stimuli. Explanations for this exaggerated reactivity emphasize attention, executive function, and affective processes, but the associations among these processes is rarely investigated. To examine these interactions, we measure fear potentiated startle (FPS; Experiment 1) and neural activation (Experiment 2) in an instructed fear paradigm that manipulates attentional focus, demands on executive functioning, and emotion. In both studies, exaggerated emotional reactivity associated with externalizing was specific to conditions that focused attention on threat information and placed minimal demands on executive functioning. Results suggest that a crucial cognition-emotion interaction affecting externalizing is the over-prioritization and over-allocation of attention to motivationally-significant information, which in turn, may impair executive and affective regulation. PMID:22579718

  7. Pupillometric evidence for the decoupling of attention from perceptual input during offline thought.

    PubMed

    Smallwood, Jonathan; Brown, Kevin S; Tipper, Christine; Giesbrecht, Barry; Franklin, Michael S; Mrazek, Michael D; Carlson, Jean M; Schooler, Jonathan W

    2011-03-25

    Accumulating evidence suggests that the brain can efficiently process both external and internal information. The processing of internal information is a distinct "offline" cognitive mode that requires not only spontaneously generated mental activity; it has also been hypothesized to require a decoupling of attention from perception in order to separate competing streams of internal and external information. This process of decoupling is potentially adaptive because it could prevent unimportant external events from disrupting an internal train of thought. Here, we use measurements of pupil diameter (PD) to provide concrete evidence for the role of decoupling during spontaneous cognitive activity. First, during periods conducive to offline thought but not during periods of task focus, PD exhibited spontaneous activity decoupled from task events. Second, periods requiring external task focus were characterized by large task evoked changes in PD; in contrast, encoding failures were preceded by episodes of high spontaneous baseline PD activity. Finally, high spontaneous PD activity also occurred prior to only the slowest 20% of correct responses, suggesting high baseline PD indexes a distinct mode of cognitive functioning. Together, these data are consistent with the decoupling hypothesis, which suggests that the capacity for spontaneous cognitive activity depends upon minimizing disruptions from the external world.

  8. Using a Template to Facilitate External Peer Preview of Curriculum: A Variation on the PRoT Theme

    ERIC Educational Resources Information Center

    Sealey, Rebecca

    2013-01-01

    Peer reviewing of teaching and curriculum in Higher Education is a common practice aimed at both quality assurance and professional development. External review of curriculum prior to implementation appears less common. The aim of this project was to develop, implement and evaluate a user-friendly process for external peer preview of teaching…

  9. Scientific Team Effectiveness and the External CEO: A Study of Biotechnology University Spin-Offs

    ERIC Educational Resources Information Center

    van der Steen, Marianne; Englis, Paula Danskin; Englis, Basil G.

    2013-01-01

    This paper presents an empirical exploration of the effectiveness of scientific teams and the role of an external CEO in the spin-off formation process. The paper contributes to the literature by focusing on the role of the experienced or "external" entrepreneur (their commercial resources and capabilities) in the early phase of spin-off…

  10. The Association between Positive Parenting and Externalizing Behavior1

    PubMed Central

    Boeldt, Debra L.; Rhee, Soo Hyun; DiLalla, Lisabeth F.; Mullineaux, Paula Y.; Schulz-Heik, R. Jay; Corley, Robin P.; Young, Susan E.; Hewitt, John. K.

    2011-01-01

    The present study examined the role of positive parenting on externalizing behaviors in a longitudinal, genetically informative sample. It often is assumed that positive parenting prevents behavior problems in children via an environmentally mediated process. Alternatively, the association may be due to either an evocative gene-environment correlation, in which parents react to children’s genetically-influenced behavior in a positive way, or a passive gene-environment correlation, where parents passively transmit a risk environment and the genetic risk factor for the behavioral outcome to their children. The present study estimated the contribution of these processes in the association between positive parenting and children’s externalizing behavior. Positive parenting was assessed via observations at ages 7, 9, 14, 24, and 36 months and externalizing behaviors were assessed through parent report at ages 4, 5, 7, 9, 10, 11, and 12 years. The significant association between positive parenting and externalizing behavior was negative, with children of mothers who showed significantly more positive parenting during toddlerhood having lower levels of externalizing behavior in childhood; however, there was not adequate power to distinguish whether this covariation was due to genetic, shared environmental, or nonshared environmental influences. PMID:22577341

  11. Spanking and Children’s Externalizing Behavior Across the First Decade of Life: Evidence for Transactional Processes

    PubMed Central

    MacKenzie, Michael J.; Nicklas, Eric; Brooks-Gunn, Jeanne; Waldfogel, Jane

    2016-01-01

    Despite a growing literature associating physical discipline with later child aggression, spanking remains a typical experience for American children. The directionality of the associations between aggression and spanking and their continuity over time has received less attention. This study examined the transactional associations between spanking and externalizing behavior across the first decade of life, examining not only how spanking relates to externalizing behavior leading up to the important transition to adolescence, but whether higher levels of externalizing lead to more spanking over time as well. We use data from the Fragile families and child well-being (FFCW) study to examine maternal spanking and children’s behavior at ages 1, 3, 5, and 9 (N=1,874; 48 % girls). The FFCW is a longitudinal birth cohort study of children born between 1998 and 2000 in 20 medium to large US cities. A little over a quarter of this sample was spanked at age 1, and about half at age 3, 5, and 9. Estimates from a cross-lagged path model provided evidence of developmental continuity in both spanking and externalizing behavior, but results also highlighted important reciprocal processes taking hold early, with spanking influencing later externalizing behavior, which, in turn, predicted subsequent spanking. These bidirectional effects held across race/ethnicity and child’s gender. The findings highlight the lasting effects of early spanking, both in influencing early child’s behavior, and in affecting subsequent child’s externalizing and parental spanking in a reciprocal manner. These amplifying transactional processes underscore the importance of early intervention before patterns may cascade across domains in the transition to adolescence. PMID:24664147

  12. Effect of solute immobilization on the stability problem within the fractional model in the solute analog of the Horton-Rogers-Lapwood problem.

    PubMed

    Klimenko, Lyudmila S; Maryshev, Boris S

    2017-11-24

    The paper is devoted to the linear stability analysis within the solute analogue of the Horton-Rogers-Lapwood (HRL) problem. The solid nanoparticles are treated as solute within the continuous approach. Therefore, we consider the infinite horizontal porous layer saturated with a mixture (carrier fluid and solute). Solute transport in porous media is very often complicated by solute immobilization on a solid matrix of porous media. Solute immobilization (solute sorption) is taken into account within the fractal model of the MIM approach. According to this model a solute in porous media immobilizes within random time intervals and the distribution of such random variable does not have a finite mean value, which has a good agreement with some experiments. The solute concentration difference between the layer boundaries is assumed as constant. We consider two cases of horizontal external filtration flux: constant and time-modulated. For the constant flux the system of equations that determines the frequency of neutral oscillations and the critical value of the Rayleigh-Darcy number is derived. Neutral curves of the critical parameters on the governing parameters are plotted. Stability maps are obtained numerically in a wide range of parameters of the system. We have found that taking immobilization into account leads to an increase in the critical value of the Rayleigh-Darcy number with an increase in the intensity of the external filtration flux. The case of weak time-dependent external flux is investigated analytically. We have shown that the modulated external flux leads to an increase in the critical value of the Rayleigh-Darcy number and a decrease in the critical wave number. For moderate time-dependent filtration flux the differential equation with Caputo fractional derivatives has been obtained for the description of the behavior near the convection instability threshold. This equation is analyzed numerically by the Floquet method; the parametric excitation of convection is observed.

  13. Do hunger and exposure to food affect scores on a measure of hedonic hunger? An experimental study.

    PubMed

    Witt, Ashley A; Raggio, Greer A; Butryn, Meghan L; Lowe, Michael R

    2014-03-01

    Research suggests that visceral bodily states, such as hunger, can affect participants' responses on self-report measures of eating behavior. The present study evaluated the influence of hunger and exposure to palatable food on self-reported hedonic appetite, measured using the Power of Food Scale (PFS). A secondary aim was to evaluate the effects of these manipulations on self-reported external eating and disinhibition. Participants (N=67) ate a standardized meal followed by a 4-h fast. Participants were randomized to one of four groups (Fasted/Food Absence, Fasted/Food Exposure, Fed/Food Absence, or Fed/Food Exposure). In Phase I of the experiment (Hunger Manipulation), participants randomized to the "Fed" group drank a protein shake, while those in the "Fasted" group did not receive a shake. In Phase II (Palatable Food Exposure), participants in the "Food Exposure" group were visually exposed to palatable food items, while "Food Absence" participants were not. All participants completed the PFS, Dutch Eating Behavior Questionnaire External Eating subscale, and the Disinhibition subscale from the Eating Inventory during Phase II. Results showed no significant main or interactive effects of Hunger condition or Food Exposure condition on PFS, External Eating, or Disinhibition scores (all p's<.33). All effect sizes were small (partial etas squared ⩽.015). Manipulation checks confirmed that the intended hunger and exposure interventions were successful. Results suggest that relatively short fasting periods (e.g., 4h) analogous to typical breaks between meals are not associated with changes in scores on the PFS, External Eating, or Disinhibition scales. Hedonic hunger, at least as measured by the PFS, may represent a relatively stable construct that is not substantially affected by daily variations in hunger. In addition, individual differences in exposure to food in the immediate environment are unlikely to confound research using these measures. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Endovascular Versus External Targeted Temperature Management for Patients With Out-of-Hospital Cardiac Arrest: A Randomized, Controlled Study.

    PubMed

    Deye, Nicolas; Cariou, Alain; Girardie, Patrick; Pichon, Nicolas; Megarbane, Bruno; Midez, Philippe; Tonnelier, Jean-Marie; Boulain, Thierry; Outin, Hervé; Delahaye, Arnaud; Cravoisy, Aurélie; Mercat, Alain; Blanc, Pascal; Santré, Charles; Quintard, Hervé; Brivet, François; Charpentier, Julien; Garrigue, Delphine; Francois, Bruno; Quenot, Jean-Pierre; Vincent, François; Gueugniaud, Pierre-Yves; Mira, Jean-Paul; Carli, Pierre; Vicaut, Eric; Baud, Frédéric J

    2015-07-21

    Targeted temperature management is recommended after out-of-hospital cardiac arrest. Whether advanced internal cooling is superior to basic external cooling remains unknown. The aim of this multicenter, controlled trial was to evaluate the benefit of endovascular versus basic surface cooling. Inclusion criteria were the following: age of 18 to 79 years, out-of-hospital cardiac arrest related to a presumed cardiac cause, time to return of spontaneous circulation <60 minutes, delay between return of spontaneous circulation and inclusion <240 minutes, and unconscious patient after return of spontaneous circulation and before the start of cooling. Exclusion criteria were terminal disease, pregnancy, known coagulopathy, uncontrolled bleeding, temperature on admission <30°C, in-hospital cardiac arrest, immediate need for extracorporeal life support or hemodialysis. Patients were randomized between 2 cooling strategies: endovascular femoral devices (Icy catheter, Coolgard, Zoll, formerly Alsius; n=203) or basic external cooling using fans, a homemade tent, and ice packs (n=197). The primary end point, that is, favorable outcome evaluated by survival without major neurological damage (Cerebral Performance Categories 1-2) at day 28, was not significantly different between groups (odds ratio, 1.41; 95% confidence interval, 0.93-2.16; P=0.107). Improvement in favorable outcome at day 90 in favor of the endovascular group did not reach significance (odds ratio, 1.51; 95% confidence interval, 0.96-2.35; P=0.07). Time to target temperature (33°C) was significantly shorter and target hypothermia was more strictly maintained in the endovascular than in the surface group (P<0.001). Minor side effects directly related to the cooling method were observed more frequently in the endovascular group (P=0.009). Despite better hypothermia induction and maintenance, endovascular cooling was not significantly superior to basic external cooling in terms of favorable outcome. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00392639. © 2015 American Heart Association, Inc.

  15. Quantitative structure-activity relationships for organophosphates binding to acetylcholinesterase.

    PubMed

    Ruark, Christopher D; Hack, C Eric; Robinson, Peter J; Anderson, Paul E; Gearhart, Jeffery M

    2013-02-01

    Organophosphates are a group of pesticides and chemical warfare nerve agents that inhibit acetylcholinesterase, the enzyme responsible for hydrolysis of the excitatory neurotransmitter acetylcholine. Numerous structural variants exist for this chemical class, and data regarding their toxicity can be difficult to obtain in a timely fashion. At the same time, their use as pesticides and military weapons is widespread, which presents a major concern and challenge in evaluating human toxicity. To address this concern, a quantitative structure-activity relationship (QSAR) was developed to predict pentavalent organophosphate oxon human acetylcholinesterase bimolecular rate constants. A database of 278 three-dimensional structures and their bimolecular rates was developed from 15 peer-reviewed publications. A database of simplified molecular input line entry notations and their respective acetylcholinesterase bimolecular rate constants are listed in Supplementary Material, Table I. The database was quite diverse, spanning 7 log units of activity. In order to describe their structure, 675 molecular descriptors were calculated using AMPAC 8.0 and CODESSA 2.7.10. Orthogonal projection to latent structures regression, bootstrap leave-random-many-out cross-validation and y-randomization were used to develop an externally validated consensus QSAR model. The domain of applicability was assessed by the William's plot. Six external compounds were outside the warning leverage indicating potential model extrapolation. A number of compounds had residuals >2 or <-2, indicating potential outliers or activity cliffs. The results show that the HOMO-LUMO energy gap contributed most significantly to the binding affinity. A mean training R (2) of 0.80, a mean test set R (2) of 0.76 and a consensus external test set R (2) of 0.66 were achieved using the QSAR. The training and external test set RMSE values were found to be 0.76 and 0.88. The results suggest that this QSAR model can be used in physiologically based pharmacokinetic/pharmacodynamic models of organophosphate toxicity to determine the rate of acetylcholinesterase inhibition.

  16. The Variable Polarity Plasma Arc Welding Process: Its Application to the Space Shuttle External Tank

    NASA Technical Reports Server (NTRS)

    Nunes, A. C., Jr.; Bayless, E. O., Jr.; Wilson, W. A.

    1984-01-01

    This report describes progress in the implementation of the Variable Polarity Plasma Arc Welding (VPPAW) process at the External Tank (ET) assembly facility. Design allowable data has been developed for thicknesses up to 1.00 in. More than 24,000 in. of welding on liquid oxygen and liquid hydrogen cylinders has been made without an internal defect.

  17. Effect of random surface inhomogeneities on spectral properties of dielectric-disk microresonators: theory and modeling at millimeter wave range.

    PubMed

    Ganapolskii, E M; Eremenko, Z E; Tarasov, Yu V

    2009-04-01

    The influence of random axially homogeneous surface roughness on spectral properties of dielectric resonators of circular disk form is studied both theoretically and experimentally. To solve the equations governing the dynamics of electromagnetic fields, the method of eigenmode separation is applied previously developed with reference to inhomogeneous systems subject to arbitrary external static potential. We prove theoretically that it is the gradient mechanism of wave-surface scattering that is highly responsible for nondissipative loss in the resonator. The influence of side-boundary inhomogeneities on the resonator spectrum is shown to be described in terms of effective renormalization of mode wave numbers jointly with azimuth indices in the characteristic equation. To study experimentally the effect of inhomogeneities on the resonator spectrum, the method of modeling in the millimeter wave range is applied. As a model object, we use a dielectric disk resonator (DDR) fitted with external inhomogeneities randomly arranged at its side boundary. Experimental results show good agreement with theoretical predictions as regards the predominance of the gradient scattering mechanism. It is shown theoretically and confirmed in the experiment that TM oscillations in the DDR are less affected by surface inhomogeneities than TE oscillations with the same azimuth indices. The DDR model chosen for our study as well as characteristic equations obtained thereupon enable one to calculate both the eigenfrequencies and the Q factors of resonance spectral lines to fairly good accuracy. The results of calculations agree well with obtained experimental data.

  18. A Double-Blind Placebo-Controlled Randomized Clinical Trial With Magnesium Oxide to Reduce Intrafraction Prostate Motion for Prostate Cancer Radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lips, Irene M., E-mail: i.m.lips@umcutrecht.nl; Gils, Carla H. van; Kotte, Alexis N.T.J.

    2012-06-01

    Purpose: To investigate whether magnesium oxide during external-beam radiotherapy for prostate cancer reduces intrafraction prostate motion in a double-blind, placebo-controlled randomized trial. Methods and Materials: At the Department of Radiotherapy, prostate cancer patients scheduled for intensity-modulated radiotherapy (77 Gy in 35 fractions) using fiducial marker-based position verification were randomly assigned to receive magnesium oxide (500 mg twice a day) or placebo during radiotherapy. The primary outcome was the proportion of patients with clinically relevant intrafraction prostate motion, defined as the proportion of patients who demonstrated in {>=}50% of the fractions an intrafraction motion outside a range of 2 mm. Secondarymore » outcome measures included quality of life and acute toxicity. Results: In total, 46 patients per treatment arm were enrolled. The primary endpoint did not show a statistically significant difference between the treatment arms with a percentage of patients with clinically relevant intrafraction motion of 83% in the magnesium oxide arm as compared with 80% in the placebo arm (p = 1.00). Concerning the secondary endpoints, exploratory analyses demonstrated a trend towards worsened quality of life and slightly more toxicity in the magnesium oxide arm than in the placebo arm; however, these differences were not statistically significant. Conclusions: Magnesium oxide is not effective in reducing the intrafraction prostate motion during external-beam radiotherapy, and therefore there is no indication to use it in clinical practice for this purpose.« less

  19. Flexible sampling large-scale social networks by self-adjustable random walk

    NASA Astrophysics Data System (ADS)

    Xu, Xiao-Ke; Zhu, Jonathan J. H.

    2016-12-01

    Online social networks (OSNs) have become an increasingly attractive gold mine for academic and commercial researchers. However, research on OSNs faces a number of difficult challenges. One bottleneck lies in the massive quantity and often unavailability of OSN population data. Sampling perhaps becomes the only feasible solution to the problems. How to draw samples that can represent the underlying OSNs has remained a formidable task because of a number of conceptual and methodological reasons. Especially, most of the empirically-driven studies on network sampling are confined to simulated data or sub-graph data, which are fundamentally different from real and complete-graph OSNs. In the current study, we propose a flexible sampling method, called Self-Adjustable Random Walk (SARW), and test it against with the population data of a real large-scale OSN. We evaluate the strengths of the sampling method in comparison with four prevailing methods, including uniform, breadth-first search (BFS), random walk (RW), and revised RW (i.e., MHRW) sampling. We try to mix both induced-edge and external-edge information of sampled nodes together in the same sampling process. Our results show that the SARW sampling method has been able to generate unbiased samples of OSNs with maximal precision and minimal cost. The study is helpful for the practice of OSN research by providing a highly needed sampling tools, for the methodological development of large-scale network sampling by comparative evaluations of existing sampling methods, and for the theoretical understanding of human networks by highlighting discrepancies and contradictions between existing knowledge/assumptions of large-scale real OSN data.

  20. Family Adversity, Positive Peer Relationships, and Children's Externalizing Behavior: A Longitudinal Perspective on Risk and Resilience

    PubMed Central

    Criss, Michael M.; Pettit, Gregory S.; Bates, John E.; Dodge, Kenneth A.; Lapp, Amie L.

    2009-01-01

    Peer acceptance and friendships were examined as moderators in the link between family adversity and child externalizing behavioral problems. Data on family adversity (i.e., ecological disadvantage, violent marital conflict, and harsh discipline) and child temperament and social information processing were collected during home visits from 585 families with 5-year-old children. Children's peer acceptance, friendship, and friends' aggressiveness were assessed with sociometric methods in kindergarten and grade 1. Teachers provided ratings of children's externalizing behavior problems in grade 2. Peer acceptance served as a moderator for all three measures of family adversity, and friendship served as a moderator for harsh discipline. Examination of regression slopes indicated that family adversity was not significantly associated with child externalizing behavior at high levels of positive peer relationships. These moderating effects generally were not qualified by child gender, ethnicity, or friends' aggressiveness, nor were they accounted for by child temperament or social information-processing patterns. The need for process-oriented studies of risk and protective factors is stressed. PMID:12146744

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