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Sample records for expected utility maximization

  1. Expected Power-Utility Maximization Under Incomplete Information and with Cox-Process Observations

    SciTech Connect

    Fujimoto, Kazufumi; Nagai, Hideo; Runggaldier, Wolfgang J.

    2013-02-15

    We consider the problem of maximization of expected terminal power utility (risk sensitive criterion). The underlying market model is a regime-switching diffusion model where the regime is determined by an unobservable factor process forming a finite state Markov process. The main novelty is due to the fact that prices are observed and the portfolio is rebalanced only at random times corresponding to a Cox process where the intensity is driven by the unobserved Markovian factor process as well. This leads to a more realistic modeling for many practical situations, like in markets with liquidity restrictions; on the other hand it considerably complicates the problem to the point that traditional methodologies cannot be directly applied. The approach presented here is specific to the power-utility. For log-utilities a different approach is presented in Fujimoto et al. (Preprint, 2012).

  2. Expected utility maximization in motor decision-making: differences in representing probability through size vs. through distance.

    PubMed

    Aguilar-Lleyda, David; Tubau, Elisabet; López-Moliner, Joan

    2015-01-01

    Humans are traditionally depicted as suboptimal decision-makers, since they often fail to maximize expected utility. However, recent studies claim people choose optimally in tasks called motor lotteries, where participants reach to different targets within a maximum time window in order to get a reward. A difference is that, while in classical tasks probability information is explicitly given, in motor tasks it is implicit in each participant's motor variability. Once this variability is known, a target can be designed to match a specific probability of being hit. This manipulation is normally implemented through size, but little has been done to explore other ways to represent probability in a motor task: for instance, through distance. Our experiment studied differences in expected utility maximization between these two ways of representing probabilities. In each of our two different conditions, trials consisted in the presentation of two targets, one with a lower probability to be hit but higher gain (risky) and another with higher probability and lower gain (safe). Participants decided to reach for one or another. In the size condition, both targets appeared at the same distance, but the risky was smaller. In the distance condition, both targets had equal size, but the risky was further away. Probabilities were manipulated to sample various expected gain differences between both targets. Results showed clear differences. Risk aversion was more present in the distance condition: participants tended to reach for the safe target even if the optimal choice was the risky target. In the size condition, participants were more sensitive to expected value differences: the more this difference favored the risky target, the more it was chosen. These differences may be interpreted as participants considering additional cost functions (e.g. biomechanical) in the distance condition not captured by the mere probability of hitting. Meeting abstract presented at VSS 2015. PMID:26326834

  3. When the Players Are Not Expectation Maximizers

    NASA Astrophysics Data System (ADS)

    Fiat, Amos; Papadimitriou, Christos

    Much of Game Theory, including the Nash equilibrium concept, is based on the assumption that players are expectation maximizers. It is known that if players are risk averse, games may no longer have Nash equilibria [11,6]. We show that

  4. Expectation maximization applied to GMTI convoy tracking

    NASA Astrophysics Data System (ADS)

    Koch, Wolfgang

    2002-08-01

    Collectively moving ground targets are typical of a military ground situation and have to be treated as separate aggregated entities. For a long-range ground surveillance application with airborne GMTI radar we inparticular address the task of track maintenance for ground moving convoys consisting of a small number of individual vehicles. In the proposed approach the identity of the individual vehicles within the convoy is no longer stressed. Their kinematical state vectors are rather treated as internal degrees of freedom characterizing the convoy, which is considered as a collective unit. In this context, the Expectation Maximization technique (EM), originally developed for incomplete data problems in statistical inference and first applied to tracking applications by STREIT et al. seems to be a promising approach. We suggest to embed the EM algorithm into a more traditional Bayesian tracking framework for dealing with false or unwanted sensor returns. The proposed distinction between external and internal data association conflicts (i.e. those among the convoy vehicles) should also enable the application of sequential track extraction techniques introduced by Van Keuk for aircraft formations, providing estimates of the number of the individual convoy vehicles involved. Even with sophisticated signal processing methods (STAP: Space-Time Adaptive Processing), ground moving vehicles can well be masked by the sensor specific clutter notch (Doppler blinding). This physical phenomenon results in interfering fading effects, which can well last over a longer series of sensor updates and therefore will seriously affect the track quality unless properly handled. Moreover, for ground moving convoys the phenomenon of Doppler blindness often superposes the effects induced by the finite resolution capability of the sensor. In many practical cases a separate modeling of resolution phenomena for convoy targets can therefore be omitted, provided the GMTI detection model is used. As an illustration we consider the contribution of the proposed GMTI sensor model to the problem of early recognition of a stopping convoy.

  5. Maximizing Resource Utilization in Video Streaming Systems

    ERIC Educational Resources Information Center

    Alsmirat, Mohammad Abdullah

    2013-01-01

    Video streaming has recently grown dramatically in popularity over the Internet, Cable TV, and wire-less networks. Because of the resource demanding nature of video streaming applications, maximizing resource utilization in any video streaming system is a key factor to increase the scalability and decrease the cost of the system. Resources to…

  6. Maximizing Resource Utilization in Video Streaming Systems

    ERIC Educational Resources Information Center

    Alsmirat, Mohammad Abdullah

    2013-01-01

    Video streaming has recently grown dramatically in popularity over the Internet, Cable TV, and wire-less networks. Because of the resource demanding nature of video streaming applications, maximizing resource utilization in any video streaming system is a key factor to increase the scalability and decrease the cost of the system. Resources to

  7. Blood detection in wireless capsule endoscopy using expectation maximization clustering

    NASA Astrophysics Data System (ADS)

    Hwang, Sae; Oh, JungHwan; Cox, Jay; Tang, Shou Jiang; Tibbals, Harry F.

    2006-03-01

    Wireless Capsule Endoscopy (WCE) is a relatively new technology (FDA approved in 2002) allowing doctors to view most of the small intestine. Other endoscopies such as colonoscopy, upper gastrointestinal endoscopy, push enteroscopy, and intraoperative enteroscopy could be used to visualize up to the stomach, duodenum, colon, and terminal ileum, but there existed no method to view most of the small intestine without surgery. With the miniaturization of wireless and camera technologies came the ability to view the entire gestational track with little effort. A tiny disposable video capsule is swallowed, transmitting two images per second to a small data receiver worn by the patient on a belt. During an approximately 8-hour course, over 55,000 images are recorded to a worn device and then downloaded to a computer for later examination. Typically, a medical clinician spends more than two hours to analyze a WCE video. Research has been attempted to automatically find abnormal regions (especially bleeding) to reduce the time needed to analyze the videos. The manufacturers also provide the software tool to detect the bleeding called Suspected Blood Indicator (SBI), but its accuracy is not high enough to replace human examination. It was reported that the sensitivity and the specificity of SBI were about 72% and 85%, respectively. To address this problem, we propose a technique to detect the bleeding regions automatically utilizing the Expectation Maximization (EM) clustering algorithm. Our experimental results indicate that the proposed bleeding detection method achieves 92% and 98% of sensitivity and specificity, respectively.

  8. Inexact Matching of Ontology Graphs Using Expectation-Maximization

    PubMed Central

    Doshi, Prashant; Kolli, Ravikanth; Thomas, Christopher

    2009-01-01

    We present a new method for mapping ontology schemas that address similar domains. The problem of ontology matching is crucial since we are witnessing a decentralized development and publication of ontological data. We formulate the problem of inferring a match between two ontologies as a maximum likelihood problem, and solve it using the technique of expectation-maximization (EM). Specifically, we adopt directed graphs as our model for ontology schemas and use a generalized version of EM to arrive at a map between the nodes of the graphs. We exploit the structural, lexical and instance similarity between the graphs, and differ from the previous approaches in the way we utilize them to arrive at, a possibly inexact, match. Inexact matching is the process of finding a best possible match between the two graphs when exact matching is not possible or is computationally difficult. In order to scale the method to large ontologies, we identify the computational bottlenecks and adapt the generalized EM by using a memory bounded partitioning scheme. We provide comparative experimental results in support of our method on two well-known ontology alignment benchmarks and discuss their implications. PMID:20160892

  9. [Rapid increase in maximal country specific life expectancy across cohorts].

    PubMed

    Shkol'nikov, V M; Zhdanov, D A; Andreev, E M; Vopel', Dzh V

    2014-01-01

    Linear increase in the best-practice (maximal among countries) life expectancy, known as the Oeppen-Vaupel line, is the most demonstrative image of longevity progress. This study is devoted to the analysis of trends in best-practice life expectancy across cohorts born in 1870 to 1950. Other than the conventional period life expectancy, cohort life expectancy measures the lifetime of real individuals from the population under consideration. Since mortality is mostly decreasing with time, period life expectancy in a given year is usually lower than cohort life expectancy for people born in the same year. The corresponding gap between period and cohort life expectancies increases with time. Our analysis is based on data for 24 developed countries from the Human Mortality Database for the period 1870 to 2008. To estimate life expectancy for non-extinct cohorts, we apply the Lee-Carter model to extrapolate mortality rates until the year 2050. The annual increase in the best-practice cohort life expectancy across cohorts born in 1870 to 1950 is 0,43 year, while the annual increment in the period life expectancy across the same range of years is equal to 0,28 year. The best-practice cohort life expectancy has increased from 53,7 years in 1870 to 83,8 years in 1950. During this time the gap between period and cohort life expectancies has increased from 1,2 to 10,3 years. Cohorts born in 1920 to 1950 will live longer than one can expect by looking at respective period mortality patterns. For these cohorts, the longest part of their additionally gained lifetime will be spent at ages 65 and older. This substantially changes the distribution of human lifetime among different stages of the life cycle. PMID:25306652

  10. An Expectation-Maximization Method for Calibrating Synchronous Machine Models

    SciTech Connect

    Meng, Da; Zhou, Ning; Lu, Shuai; Lin, Guang

    2013-07-21

    The accuracy of a power system dynamic model is essential to its secure and efficient operation. Lower confidence in model accuracy usually leads to conservative operation and lowers asset usage. To improve model accuracy, this paper proposes an expectation-maximization (EM) method to calibrate the synchronous machine model using phasor measurement unit (PMU) data. First, an extended Kalman filter (EKF) is applied to estimate the dynamic states using measurement data. Then, the parameters are calculated based on the estimated states using maximum likelihood estimation (MLE) method. The EM method iterates over the preceding two steps to improve estimation accuracy. The proposed EM method’s performance is evaluated using a single-machine infinite bus system and compared with a method where both state and parameters are estimated using an EKF method. Sensitivity studies of the parameter calibration using EM method are also presented to show the robustness of the proposed method for different levels of measurement noise and initial parameter uncertainty.

  11. Expectation-Maximization Binary Clustering for Behavioural Annotation

    PubMed Central

    2016-01-01

    The growing capacity to process and store animal tracks has spurred the development of new methods to segment animal trajectories into elementary units of movement. Key challenges for movement trajectory segmentation are to (i) minimize the need of supervision, (ii) reduce computational costs, (iii) minimize the need of prior assumptions (e.g. simple parametrizations), and (iv) capture biologically meaningful semantics, useful across a broad range of species. We introduce the Expectation-Maximization binary Clustering (EMbC), a general purpose, unsupervised approach to multivariate data clustering. The EMbC is a variant of the Expectation-Maximization Clustering (EMC), a clustering algorithm based on the maximum likelihood estimation of a Gaussian mixture model. This is an iterative algorithm with a closed form step solution and hence a reasonable computational cost. The method looks for a good compromise between statistical soundness and ease and generality of use (by minimizing prior assumptions and favouring the semantic interpretation of the final clustering). Here we focus on the suitability of the EMbC algorithm for behavioural annotation of movement data. We show and discuss the EMbC outputs in both simulated trajectories and empirical movement trajectories including different species and different tracking methodologies. We use synthetic trajectories to assess the performance of EMbC compared to classic EMC and Hidden Markov Models. Empirical trajectories allow us to explore the robustness of the EMbC to data loss and data inaccuracies, and assess the relationship between EMbC output and expert label assignments. Additionally, we suggest a smoothing procedure to account for temporal correlations among labels, and a proper visualization of the output for movement trajectories. Our algorithm is available as an R-package with a set of complementary functions to ease the analysis. PMID:27002631

  12. PEM-PCA: A Parallel Expectation-Maximization PCA Face Recognition Architecture

    PubMed Central

    Rujirakul, Kanokmon; Arnonkijpanich, Banchar

    2014-01-01

    Principal component analysis or PCA has been traditionally used as one of the feature extraction techniques in face recognition systems yielding high accuracy when requiring a small number of features. However, the covariance matrix and eigenvalue decomposition stages cause high computational complexity, especially for a large database. Thus, this research presents an alternative approach utilizing an Expectation-Maximization algorithm to reduce the determinant matrix manipulation resulting in the reduction of the stages' complexity. To improve the computational time, a novel parallel architecture was employed to utilize the benefits of parallelization of matrix computation during feature extraction and classification stages including parallel preprocessing, and their combinations, so-called a Parallel Expectation-Maximization PCA architecture. Comparing to a traditional PCA and its derivatives, the results indicate lower complexity with an insignificant difference in recognition precision leading to high speed face recognition systems, that is, the speed-up over nine and three times over PCA and Parallel PCA. PMID:24955405

  13. Fluorescence photobleaching correction for expectation-maximization algorithm

    NASA Astrophysics Data System (ADS)

    Conchello, Jose-Angel

    1995-03-01

    In 3D fluorescence microscopy, a series of 2D images is collected at different focal settings through the specimen. Each image in this series contains the in-focus plane plus contributions from out-of-focus structures that blur the image. Furthermore, as the series is collected the fluorescent dye in the specimen fades over time in response to the total excitation light dosage which progressively increase as more optical slices are collected. Thus the different optical slices are 2D images of different 3D objects, in the sense that at each time point, the object has a different overall intensity. To date, the approach to compensate for this decay has been to precondition the image by dividing the intensities in each optical slice by a decaying exponential before processing the image by any of a number of existing deblurring algorithms. We have now directly incorporated fluorescent decay into maximum-likelihood estimators for the 3D distribution of fluorescent dye. We derived a generalized expectation-maximization algorithm for the simultaneous estimation of the decay constant, considered homogeneous, and the distribution of fluorescent dye.

  14. Utility maximization and bounds on human information processing.

    PubMed

    Howes, Andrew; Lewis, Richard L; Singh, Satinder

    2014-04-01

    Utility maximization is a key element of a number of theoretical approaches to explaining human behavior. Among these approaches are rational analysis, ideal observer theory, and signal detection theory. While some examples of these approaches define the utility maximization problem with little reference to the bounds imposed by the organism, others start with, and emphasize approaches in which bounds imposed by the information processing architecture are considered as an explicit part of the utility maximization problem. These latter approaches are the topic of this issue of the journal. PMID:24648113

  15. Matching Pupils and Teachers to Maximize Expected Outcomes.

    ERIC Educational Resources Information Center

    Ward, Joe H., Jr.; And Others

    To achieve a good teacher-pupil match, it is necessary (1) to predict the learning outcomes that will result when each student is instructed by each teacher, (2) to use the predicted performance to compute an Optimality Index for each teacher-pupil combination to indicate the quality of each combination toward maximizing learning for all students,

  16. An expected utility maximizer walks into a bar…

    PubMed Central

    Glimcher, Paul W.; Lazzaro, Stephanie C.

    2013-01-01

    We conducted field experiments at a bar to test whether blood alcohol concentration (BAC) correlates with violations of the generalized axiom of revealed preference (GARP) and the independence axiom. We found that individuals with BACs well above the legal limit for driving adhere to GARP and independence at rates similar to those who are sober. This finding led to the fielding of a third experiment to explore how risk preferences might vary as a function of BAC. We found gender-specific effects: Men did not exhibit variations in risk preferences across BACs. In contrast, women were more risk averse than men at low BACs but exhibited increasing tolerance towards risks as BAC increased. Based on our estimates, men and women’s risk preferences are predicted to be identical at BACs nearly twice the legal limit for driving. We discuss the implications for policy-makers. PMID:24244072

  17. Coding for Parallel Links to Maximize the Expected Value of Decodable Messages

    NASA Technical Reports Server (NTRS)

    Klimesh, Matthew A.; Chang, Christopher S.

    2011-01-01

    When multiple parallel communication links are available, it is useful to consider link-utilization strategies that provide tradeoffs between reliability and throughput. Interesting cases arise when there are three or more available links. Under the model considered, the links have known probabilities of being in working order, and each link has a known capacity. The sender has a number of messages to send to the receiver. Each message has a size and a value (i.e., a worth or priority). Messages may be divided into pieces arbitrarily, and the value of each piece is proportional to its size. The goal is to choose combinations of messages to send on the links so that the expected value of the messages decodable by the receiver is maximized. There are three parts to the innovation: (1) Applying coding to parallel links under the model; (2) Linear programming formulation for finding the optimal combinations of messages to send on the links; and (3) Algorithms for assisting in finding feasible combinations of messages, as support for the linear programming formulation. There are similarities between this innovation and methods developed in the field of network coding. However, network coding has generally been concerned with either maximizing throughput in a fixed network, or robust communication of a fixed volume of data. In contrast, under this model, the throughput is expected to vary depending on the state of the network. Examples of error-correcting codes that are useful under this model but which are not needed under previous models have been found. This model can represent either a one-shot communication attempt, or a stream of communications. Under the one-shot model, message sizes and link capacities are quantities of information (e.g., measured in bits), while under the communications stream model, message sizes and link capacities are information rates (e.g., measured in bits/second). This work has the potential to increase the value of data returned from spacecraft under certain conditions.

  18. AREM: Aligning Short Reads from ChIP-Sequencing by Expectation Maximization

    NASA Astrophysics Data System (ADS)

    Newkirk, Daniel; Biesinger, Jacob; Chon, Alvin; Yokomori, Kyoko; Xie, Xiaohui

    High-throughput sequencing coupled to chromatin immunoprecipitation (ChIP-Seq) is widely used in characterizing genome-wide binding patterns of transcription factors, cofactors, chromatin modifiers, and other DNA binding proteins. A key step in ChIP-Seq data analysis is to map short reads from high-throughput sequencing to a reference genome and identify peak regions enriched with short reads. Although several methods have been proposed for ChIP-Seq analysis, most existing methods only consider reads that can be uniquely placed in the reference genome, and therefore have low power for detecting peaks located within repeat sequences. Here we introduce a probabilistic approach for ChIP-Seq data analysis which utilizes all reads, providing a truly genome-wide view of binding patterns. Reads are modeled using a mixture model corresponding to K enriched regions and a null genomic background. We use maximum likelihood to estimate the locations of the enriched regions, and implement an expectation-maximization (E-M) algorithm, called AREM (aligning reads by expectation maximization), to update the alignment probabilities of each read to different genomic locations. We apply the algorithm to identify genome-wide binding events of two proteins: Rad21, a component of cohesin and a key factor involved in chromatid cohesion, and Srebp-1, a transcription factor important for lipid/cholesterol homeostasis. Using AREM, we were able to identify 19,935 Rad21 peaks and 1,748 Srebp-1 peaks in the mouse genome with high confidence, including 1,517 (7.6%) Rad21 peaks and 227 (13%) Srebp-1 peaks that were missed using only uniquely mapped reads. The open source implementation of our algorithm is available at http://sourceforge.net/projects/arem

  19. AREM: Aligning Short Reads from ChIP-Sequencing by Expectation Maximization

    PubMed Central

    Newkirk, Daniel; Biesinger, Jacob; Chon, Alvin; Yokomori, Kyoko

    2011-01-01

    Abstract High-throughput sequencing coupled to chromatin immunoprecipitation (ChIP-Seq) is widely used in characterizing genome-wide binding patterns of transcription factors, cofactors, chromatin modifiers, and other DNA binding proteins. A key step in ChIP-Seq data analysis is to map short reads from high-throughput sequencing to a reference genome and identify peak regions enriched with short reads. Although several methods have been proposed for ChIP-Seq analysis, most existing methods only consider reads that can be uniquely placed in the reference genome, and therefore have low power for detecting peaks located within repeat sequences. Here, we introduce a probabilistic approach for ChIP-Seq data analysis that utilizes all reads, providing a truly genome-wide view of binding patterns. Reads are modeled using a mixture model corresponding to K enriched regions and a null genomic background. We use maximum likelihood to estimate the locations of the enriched regions, and implement an expectation-maximization (E-M) algorithm, called AREM (aligning reads by expectation maximization), to update the alignment probabilities of each read to different genomic locations. We apply the algorithm to identify genome-wide binding events of two proteins: Rad21, a component of cohesin and a key factor involved in chromatid cohesion, and Srebp-1, a transcription factor important for lipid/cholesterol homeostasis. Using AREM, we were able to identify 19,935 Rad21 peaks and 1,748 Srebp-1 peaks in the mouse genome with high confidence, including 1,517 (7.6%) Rad21 peaks and 227 (13%) Srebp-1 peaks that were missed using only uniquely mapped reads. The open source implementation of our algorithm is available at http://sourceforge.net/projects/arem. PMID:22035330

  20. What utilities should expect from competitive intelligence

    SciTech Connect

    Fuld, L.M.; Borska, D.L.

    1995-03-01

    Electric utilities are informationally dysfunctional. In a survey of electric utility managers, we found that while employees may possess the necessary information for decision-making, they may not understand how the information is used, why it is important, or who needs to know it. Utility managers feel that their organizations suffer from intelligence deficits in the following areas: (1) Customer Retention-Customer (rather than competitor) intelligence is desparately needed, (2) Competitor Costs-As prices drive markets, utilities must learn how competitors use the technology to gain a cost advantage, and (3) Market Savvy-Recognizing threats means more that just crunching the numbers. It means converting raw data into a strategy that will expose a competitor`s weakness. The complex economics will require companies to apply all types of intelligence to solve competitive problems. This coherent approach requires changes in the way both management and the organization handle vital intelligence.

  1. Optimal weight based on energy imbalance and utility maximization

    NASA Astrophysics Data System (ADS)

    Sun, Ruoyan

    2016-01-01

    This paper investigates the optimal weight for both male and female using energy imbalance and utility maximization. Based on the difference of energy intake and expenditure, we develop a state equation that reveals the weight gain from this energy gap. We ​construct an objective function considering food consumption, eating habits and survival rate to measure utility. Through applying mathematical tools from optimal control methods and qualitative theory of differential equations, we obtain some results. For both male and female, the optimal weight is larger than the physiologically optimal weight calculated by the Body Mass Index (BMI). We also study the corresponding trajectories to steady state weight respectively. Depending on the value of a few parameters, the steady state can either be a saddle point with a monotonic trajectory or a focus with dampened oscillations.

  2. Expectation maximization and total variation-based model for computed tomography reconstruction from undersampled data

    NASA Astrophysics Data System (ADS)

    Yan, Ming; Vese, Luminita A.

    2011-03-01

    Computerized tomography (CT) plays an important role in medical imaging, especially for diagnosis and therapy. However, higher radiation dose from CT will result in increasing of radiation exposure in the population. Therefore, the reduction of radiation from CT is an essential issue. Expectation maximization (EM) is an iterative method used for CT image reconstruction that maximizes the likelihood function under Poisson noise assumption. Total variation regularization is a technique used frequently in image restoration to preserve edges, given the assumption that most images are piecewise constant. Here, we propose a method combining expectation maximization and total variation regularization, called EM+TV. This method can reconstruct a better image using fewer views in the computed tomography setting, thus reducing the overall dose of radiation. The numerical results in two and three dimensions show the efficiency of the proposed EM+TV method by comparison with those obtained by filtered back projection (FBP) or by EM only.

  3. A compact formulation for maximizing the expected number of transplants in kidney exchange programs

    NASA Astrophysics Data System (ADS)

    Alvelos, Filipe; Klimentova, Xenia; Rais, Abdur; Viana, Ana

    2015-05-01

    Kidney exchange programs (KEPs) allow the exchange of kidneys between incompatible donor-recipient pairs. Optimization approaches can help KEPs in defining which transplants should be made among all incompatible pairs according to some objective. The most common objective is to maximize the number of transplants. In this paper, we propose an integer programming model which addresses the objective of maximizing the expected number of transplants, given that there are equal probabilities of failure associated with vertices and arcs. The model is compact, i.e. has a polynomial number of decision variables and constraints, and therefore can be solved directly by a general purpose integer programming solver (e.g. Cplex).

  4. The predictive validity of prospect theory versus expected utility in health utility measurement.

    PubMed

    Abellan-Perpian, Jose Maria; Bleichrodt, Han; Pinto-Prades, Jose Luis

    2009-12-01

    Most health care evaluations today still assume expected utility even though the descriptive deficiencies of expected utility are well known. Prospect theory is the dominant descriptive alternative for expected utility. This paper tests whether prospect theory leads to better health evaluations than expected utility. The approach is purely descriptive: we explore how simple measurements together with prospect theory and expected utility predict choices and rankings between more complex stimuli. For decisions involving risk prospect theory is significantly more consistent with rankings and choices than expected utility. This conclusion no longer holds when we use prospect theory utilities and expected utilities to predict intertemporal decisions. The latter finding cautions against the common assumption in health economics that health state utilities are transferable across decision contexts. Our results suggest that the standard gamble and algorithms based on, should not be used to value health. PMID:19833400

  5. Disconfirmation of Expectations of Utility in e-Learning

    ERIC Educational Resources Information Center

    Cacao, Rosario

    2013-01-01

    Using pre-training and post-training paired surveys in e-learning based training courses, we have compared the "expectations of utility," measured at the beginning of an e-learning course, with the "perceptions of utility," measured at the end of the course, and related it with the trainees' motivation. We have concluded

  6. Wobbling and LSF-based maximum likelihood expectation maximization reconstruction for wobbling PET

    NASA Astrophysics Data System (ADS)

    Kim, Hang-Keun; Son, Young-Don; Kwon, Dae-Hyuk; Joo, Yohan; Cho, Zang-Hee

    2016-04-01

    Positron emission tomography (PET) is a widely used imaging modality; however, the PET spatial resolution is not yet satisfactory for precise anatomical localization of molecular activities. Detector size is the most important factor because it determines the intrinsic resolution, which is approximately half of the detector size and determines the ultimate PET resolution. Detector size, however, cannot be made too small because both the decreased detection efficiency and the increased septal penetration effect degrade the image quality. A wobbling and line spread function (LSF)-based maximum likelihood expectation maximization (WL-MLEM) algorithm, which combined the MLEM iterative reconstruction algorithm with wobbled sampling and LSF-based deconvolution using the system matrix, was proposed for improving the spatial resolution of PET without reducing the scintillator or detector size. The new algorithm was evaluated using a simulation, and its performance was compared with that of the existing algorithms, such as conventional MLEM and LSF-based MLEM. Simulations demonstrated that the WL-MLEM algorithm yielded higher spatial resolution and image quality than the existing algorithms. The WL-MLEM algorithm with wobbling PET yielded substantially improved resolution compared with conventional algorithms with stationary PET. The algorithm can be easily extended to other iterative reconstruction algorithms, such as maximum a priori (MAP) and ordered subset expectation maximization (OSEM). The WL-MLEM algorithm with wobbling PET may offer improvements in both sensitivity and resolution, the two most sought-after features in PET design.

  7. An expectation-maximization approach to joint curve evolution for medical image segmentation

    NASA Astrophysics Data System (ADS)

    Farzinfar, Mahshid; Teoh, Eam Khwang; Xue, Zhong

    2010-03-01

    This paper proposes a new Expectation-Maximization curve evolution algorithm for medical image segmentation. Traditional level set algorithms perform poorly when image information is incomplete, missing or some objects are corrupted. In such cases, statistical model-based segmentation methods are widely used since they allow object shape variations subject to shape prior constraints to overcome the incomplete or noisy information. Although matching robustly in dealing with noisy and low contrast images, the shape parameters are estimated intractably through the Maximum A Posterior (MAP) framework by using incomplete image features. In this paper, we present a statistical shape-based joint curve evolution algorithm for image segmentation based on the assumption that using hidden features of the image as missing data can simplify the estimation problem and help improve the matching performance. In our method, these hidden features are designed to be the local voxel labeling data determined based on the intensity distribution of the image and priori anatomical knowledge. Using an Expectation-Maximization formulation, both the hidden features and the object shapes can be extracted. In addition, this EM-based algorithm is applied to the joint parameter and non-parameter shape model for more accurate segmentation. Comparative results on segmenting putamen and caudate shapes in MR brain images confirm both robustness and accuracy of the proposed curve evolution algorithm.

  8. A comparison of alternating minimization and expectation maximization algorithms for single source gamma ray tomography

    NASA Astrophysics Data System (ADS)

    Varma, R.; Bhusarapu, S.; O'Sullivan, J. A.; Al-Dahhan, M. H.

    2008-01-01

    Lange and Carson (1984 J. Comput. Assist. Tomogr. 8 306-16) defined image reconstruction for transmission tomography as a maximum likelihood estimation problem and derived an expectation maximization (EM) algorithm to obtain the maximum likelihood image estimate. However, in the maximization step or M-step of the EM algorithm, an approximation is made in the solution which can affect the image quality, particularly in the case of domains with high attenuating material. O'Sullivan and Benac (2007 IEEE Trans. Med. Imaging 26 283-97) reformulated the maximum likelihood problem as a double minimization of an I-divergence to obtain a family of image reconstruction algorithms, called the alternating minimization (AM) algorithm. The AM algorithm increases the log-likelihood function while minimizing the I-divergence. In this work, we implement the AM algorithm for image reconstruction in gamma ray tomography for industrial applications. Experimental gamma ray transmission data obtained with a fan beam geometry gamma ray scanner, and simulated transmission data based on a synthetic phantom, with two phases (water and air) were considered in this study. Image reconstruction was carried out with these data using the AM and the EM algorithms to determine and quantitatively compare the holdup distribution images of the two phases in the phantoms. When compared to the EM algorithm, the AM algorithm shows qualitative and quantitative improvement in the holdup distribution images of the two phases for both the experimental and the simulated gamma ray transmission data.

  9. Maximizing Light Utilization Efficiency and Hydrogen Production in Microalgal Cultures

    SciTech Connect

    Melis, Anastasios

    2014-12-31

    The project addressed the following technical barrier from the Biological Hydrogen Production section of the Fuel Cell Technologies Program Multi-Year Research, Development and Demonstration Plan: Low Sunlight Utilization Efficiency in Photobiological Hydrogen Production is due to a Large Photosystem Chlorophyll Antenna Size in Photosynthetic Microorganisms (Barrier AN: Light Utilization Efficiency).

  10. An Expectation Maximization based Method for Subcellular Particle Tracking using Multi-angle TIRF Microscopy*

    PubMed Central

    Liang, Liang; Shen, Hongying; De Camilli, Pietro; Toomre, Derek K.; Duncan, James S.

    2013-01-01

    Multi-angle total internal reflection fluorescence microscopy (MA-TIRFM) is a new generation of TIRF microscopy to study cellular processes near dorsal cell membrane in 4 dimensions (3D+t). To perform quantitative analysis using MA-TIRFM, it is necessary to track subcellular particles in these processes. In this paper, we propose a method based on a MAP framework for automatic particle tracking and apply it to track clathrin coated pits (CCPs). The expectation maximization (EM) algorithm is employed to solve the MAP problem. To provide the initial estimations for the EM algorithm, we develop a forward filter based on the most probable trajectory (MPT) filter. Multiple linear models are used to model particle dynamics. For CCP tracking, we use two linear models to describe constrained Brownian motion and fluorophore variation according to CCP properties. The tracking method is evaluated on synthetic data and results show that it has high accuracy. The result on real data confirmed by human expert cell biologists is also presented. PMID:22003671

  11. An online expectation maximization algorithm for exploring general structure in massive networks

    NASA Astrophysics Data System (ADS)

    Chai, Bianfang; Jia, Caiyan; Yu, Jian

    2015-11-01

    Mixture model and stochastic block model (SBM) for structure discovery employ a broad and flexible definition of vertex classes such that they are able to explore a wide variety of structure. Compared to the existing algorithms based on the SBM (their time complexities are O(mc2) , where m and c are the number of edges and clusters), the algorithms of mixture model are capable of dealing with networks with a large number of communities more efficiently due to their O(mc) time complexity. However, the algorithms of mixture model using expectation maximization (EM) technique are still too slow to deal with real million-node networks, since they compute hidden variables on the entire network in each iteration. In this paper, an online variational EM algorithm is designed to improve the efficiency of the EM algorithms. In each iteration, our online algorithm samples a node and estimates its cluster memberships only by its adjacency links, and model parameters are then estimated by the memberships of the sampled node and old model parameters obtained in the previous iteration. The provided online algorithm updates model parameters subsequently by the links of a new sampled node and explores the general structure of massive and growing networks with millions of nodes and hundreds of clusters in hours. Compared to the relevant algorithms on synthetic and real networks, the proposed online algorithm costs less with little or no degradation of accuracy. Results illustrate that the presented algorithm offers a good trade-off between precision and efficiency.

  12. The indexing ambiguity in serial femtosecond crystallography (SFX) resolved using an expectation maximization algorithm.

    PubMed

    Liu, Haiguang; Spence, John C H

    2014-11-01

    Crystallographic auto-indexing algorithms provide crystal orientations and unit-cell parameters and assign Miller indices based on the geometric relations between the Bragg peaks observed in diffraction patterns. However, if the Bravais symmetry is higher than the space-group symmetry, there will be multiple indexing options that are geometrically equivalent, and hence many ways to merge diffraction intensities from protein nanocrystals. Structure factor magnitudes from full reflections are required to resolve this ambiguity but only partial reflections are available from each XFEL shot, which must be merged to obtain full reflections from these 'stills'. To resolve this chicken-and-egg problem, an expectation maximization algorithm is described that iteratively constructs a model from the intensities recorded in the diffraction patterns as the indexing ambiguity is being resolved. The reconstructed model is then used to guide the resolution of the indexing ambiguity as feedback for the next iteration. Using both simulated and experimental data collected at an X-ray laser for photosystem I in the P63 space group (which supports a merohedral twinning indexing ambiguity), the method is validated. PMID:25485120

  13. Statistical models of synaptic transmission evaluated using the expectation-maximization algorithm.

    PubMed Central

    Stricker, C; Redman, S

    1994-01-01

    Amplitude fluctuations of evoked synaptic responses can be used to extract information on the probabilities of release at the active sites, and on the amplitudes of the synaptic responses generated by transmission at each active site. The parameters that describe this process must be obtained from an incomplete data set represented by the probability density of the evoked synaptic response. In this paper, the equations required to calculate these parameters using the Expectation-Maximization algorithm and the maximum likelihood criterion have been derived for a variety of statistical models of synaptic transmission. These models are ones where the probabilities associated with the different discrete amplitudes in the evoked responses are a) unconstrained, b) binomial, and c) compound binomial. The discrete amplitudes may be separated by equal (quantal) or unequal amounts, with or without quantal variance. Alternative models have been considered where the variance associated with the discrete amplitudes is sufficiently large such that no quantal amplitudes can be detected. These models involve the sum of a normal distribution (to represent failures) and a unimodal distribution (to represent the evoked responses). The implementation of the algorithm is described in each case, and its accuracy and convergence have been demonstrated. PMID:7948679

  14. Expectation maximization (EM) algorithms using polar symmetries for computed tomography (CT) image reconstruction.

    PubMed

    Rodrguez-Alvarez, M J; Soriano, A; Iborra, A; Snchez, F; Gonzlez, A J; Conde, P; Hernndez, L; Moliner, L; Orero, A; Vidal, L F; Benlloch, J M

    2013-09-01

    We suggest a symmetric-polar pixellation scheme which makes possible a reduction of the computational cost for expectation maximization (EM) iterative algorithms. The proposed symmetric-polar pixellation allows us to deal with 3D images as a whole problem without dividing the 3D problem into 2D slices approach. Performance evaluation of each approach in terms of stability and image quality is presented. Exhaustive comparisons between all approaches were conducted in a 2D based image reconstruction model. From these 2D approaches, that showing the best performances were finally implemented and evaluated in a 3D based image reconstruction model. Comparison to 3D images reconstructed with FBP is also presented. Although the algorithm is presented in the context of computed tomography (CT) image reconstruction, it can be applied to any other tomographic technique as well, due to the fact that the only requirement is a scanning geometry involving measurements of an object under different projection angles. Real data have been acquired with a small animal (CT) scanner to verify the proposed mathematical description of the CT system. PMID:23706690

  15. A Local Scalable Distributed Expectation Maximization Algorithm for Large Peer-to-Peer Networks

    NASA Technical Reports Server (NTRS)

    Bhaduri, Kanishka; Srivastava, Ashok N.

    2009-01-01

    This paper offers a local distributed algorithm for expectation maximization in large peer-to-peer environments. The algorithm can be used for a variety of well-known data mining tasks in a distributed environment such as clustering, anomaly detection, target tracking to name a few. This technology is crucial for many emerging peer-to-peer applications for bioinformatics, astronomy, social networking, sensor networks and web mining. Centralizing all or some of the data for building global models is impractical in such peer-to-peer environments because of the large number of data sources, the asynchronous nature of the peer-to-peer networks, and dynamic nature of the data/network. The distributed algorithm we have developed in this paper is provably-correct i.e. it converges to the same result compared to a similar centralized algorithm and can automatically adapt to changes to the data and the network. We show that the communication overhead of the algorithm is very low due to its local nature. This monitoring algorithm is then used as a feedback loop to sample data from the network and rebuild the model when it is outdated. We present thorough experimental results to verify our theoretical claims.

  16. Colocalization Estimation Using Graphical Modeling and Variational Bayesian Expectation Maximization: Towards a Parameter-Free Approach.

    PubMed

    Awate, Suyash P; Radhakrishnan, Thyagarajan

    2015-01-01

    In microscopy imaging, colocalization between two biological entities (e.g., protein-protein or protein-cell) refers to the (stochastic) dependencies between the spatial locations of the two entities in the biological specimen. Measuring colocalization between two entities relies on fluorescence imaging of the specimen using two fluorescent chemicals, each of which indicates the presence/absence of one of the entities at any pixel location. State-of-the-art methods for estimating colocalization rely on post-processing image data using an adhoc sequence of algorithms with many free parameters that are tuned visually. This leads to loss of reproducibility of the results. This paper proposes a brand-new framework for estimating the nature and strength of colocalization directly from corrupted image data by solving a single unified optimization problem that automatically deals with noise, object labeling, and parameter tuning. The proposed framework relies on probabilistic graphical image modeling and a novel inference scheme using variational Bayesian expectation maximization for estimating all model parameters, including colocalization, from data. Results on simulated and real-world data demonstrate improved performance over the state of the art. PMID:26221663

  17. Bandwidth utilization maximization of scientific RF communication systems

    SciTech Connect

    Rey, D.; Ryan, W.; Ross, M.

    1997-01-01

    A method for more efficiently utilizing the frequency bandwidth allocated for data transmission is presented. Current space and range communication systems use modulation and coding schemes that transmit 0.5 to 1.0 bits per second per Hertz of radio frequency bandwidth. The goal in this LDRD project is to increase the bandwidth utilization by employing advanced digital communications techniques. This is done with little or no increase in the transmit power which is usually very limited on airborne systems. Teaming with New Mexico State University, an implementation of trellis coded modulation (TCM), a coding and modulation scheme pioneered by Ungerboeck, was developed for this application and simulated on a computer. TCM provides a means for reliably transmitting data while simultaneously increasing bandwidth efficiency. The penalty is increased receiver complexity. In particular, the trellis decoder requires high-speed, application-specific digital signal processing (DSP) chips. A system solution based on the QualComm Viterbi decoder and the Graychip DSP receiver chips is presented.

  18. 76 FR 51060 - Guidelines for Ensuring and Maximizing the Quality, Objectivity, Utility, and Integrity of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-17

    ... FR 8452-8460), pursuant to section 515 of the Treasury and General Government Appropriations Act for... FR 8452-8460) that direct each federal agency to (1) Issue its own guidelines ensuring and maximizing... June 2011 (76 FR 37376) intended to ensure and maximize the quality, objectivity, utility,...

  19. Optimization in the utility maximization framework for conservation planning: a comparison of solution procedures in a study of multifunctional agriculture

    PubMed Central

    Stoms, David M.; Davis, Frank W.

    2014-01-01

    Quantitative methods of spatial conservation prioritization have traditionally been applied to issues in conservation biology and reserve design, though their use in other types of natural resource management is growing. The utility maximization problem is one form of a covering problem where multiple criteria can represent the expected social benefits of conservation action. This approach allows flexibility with a problem formulation that is more general than typical reserve design problems, though the solution methods are very similar. However, few studies have addressed optimization in utility maximization problems for conservation planning, and the effect of solution procedure is largely unquantified. Therefore, this study mapped five criteria describing elements of multifunctional agriculture to determine a hypothetical conservation resource allocation plan for agricultural land conservation in the Central Valley of CA, USA. We compared solution procedures within the utility maximization framework to determine the difference between an open source integer programming approach and a greedy heuristic, and find gains from optimization of up to 12%. We also model land availability for conservation action as a stochastic process and determine the decline in total utility compared to the globally optimal set using both solution algorithms. Our results are comparable to other studies illustrating the benefits of optimization for different conservation planning problems, and highlight the importance of maximizing the effectiveness of limited funding for conservation and natural resource management. PMID:25538868

  20. Optimization in the utility maximization framework for conservation planning: a comparison of solution procedures in a study of multifunctional agriculture

    USGS Publications Warehouse

    Kreitler, Jason R.; Stoms, David M.; Davis, Frank W.

    2014-01-01

    Quantitative methods of spatial conservation prioritization have traditionally been applied to issues in conservation biology and reserve design, though their use in other types of natural resource management is growing. The utility maximization problem is one form of a covering problem where multiple criteria can represent the expected social benefits of conservation action. This approach allows flexibility with a problem formulation that is more general than typical reserve design problems, though the solution methods are very similar. However, few studies have addressed optimization in utility maximization problems for conservation planning, and the effect of solution procedure is largely unquantified. Therefore, this study mapped five criteria describing elements of multifunctional agriculture to determine a hypothetical conservation resource allocation plan for agricultural land conservation in the Central Valley of CA, USA. We compared solution procedures within the utility maximization framework to determine the difference between an open source integer programming approach and a greedy heuristic, and find gains from optimization of up to 12%. We also model land availability for conservation action as a stochastic process and determine the decline in total utility compared to the globally optimal set using both solution algorithms. Our results are comparable to other studies illustrating the benefits of optimization for different conservation planning problems, and highlight the importance of maximizing the effectiveness of limited funding for conservation and natural resource management.

  1. Optimization in the utility maximization framework for conservation planning: a comparison of solution procedures in a study of multifunctional agriculture.

    PubMed

    Kreitler, Jason; Stoms, David M; Davis, Frank W

    2014-01-01

    Quantitative methods of spatial conservation prioritization have traditionally been applied to issues in conservation biology and reserve design, though their use in other types of natural resource management is growing. The utility maximization problem is one form of a covering problem where multiple criteria can represent the expected social benefits of conservation action. This approach allows flexibility with a problem formulation that is more general than typical reserve design problems, though the solution methods are very similar. However, few studies have addressed optimization in utility maximization problems for conservation planning, and the effect of solution procedure is largely unquantified. Therefore, this study mapped five criteria describing elements of multifunctional agriculture to determine a hypothetical conservation resource allocation plan for agricultural land conservation in the Central Valley of CA, USA. We compared solution procedures within the utility maximization framework to determine the difference between an open source integer programming approach and a greedy heuristic, and find gains from optimization of up to 12%. We also model land availability for conservation action as a stochastic process and determine the decline in total utility compared to the globally optimal set using both solution algorithms. Our results are comparable to other studies illustrating the benefits of optimization for different conservation planning problems, and highlight the importance of maximizing the effectiveness of limited funding for conservation and natural resource management. PMID:25538868

  2. Computational rationality: linking mechanism and behavior through bounded utility maximization.

    PubMed

    Lewis, Richard L; Howes, Andrew; Singh, Satinder

    2014-04-01

    We propose a framework for including information-processing bounds in rational analyses. It is an application of bounded optimality (Russell & Subramanian, 1995) to the challenges of developing theories of mechanism and behavior. The framework is based on the idea that behaviors are generated by cognitive mechanisms that are adapted to the structure of not only the environment but also the mind and brain itself. We call the framework computational rationality to emphasize the incorporation of computational mechanism into the definition of rational action. Theories are specified as optimal program problems, defined by an adaptation environment, a bounded machine, and a utility function. Such theories yield different classes of explanation, depending on the extent to which they emphasize adaptation to bounds, and adaptation to some ecology that differs from the immediate local environment. We illustrate this variation with examples from three domains: visual attention in a linguistic task, manual response ordering, and reasoning. We explore the relation of this framework to existing "levels" approaches to explanation, and to other optimality-based modeling approaches. PMID:24648415

  3. The Economics of Merit Pay: A Special Case of Utility Maximization.

    ERIC Educational Resources Information Center

    Richards, Craig E.

    1985-01-01

    Examines merit pay in terms of utility maximization, which assumes an employee exerts an amount of effort providing the greatest individual utility. Pay incentives succeed when technologies are clearly specified, productivity is easily measurable, employees understand the reward structure, and risk and uncertainty are minimal. Includes 11…

  4. Direct reconstruction of the source intensity distribution of a clinical linear accelerator using a maximum likelihood expectation maximization algorithm.

    PubMed

    Papaconstadopoulos, P; Levesque, I R; Maglieri, R; Seuntjens, J

    2016-02-01

    Direct determination of the source intensity distribution of clinical linear accelerators is still a challenging problem for small field beam modeling. Current techniques most often involve special equipment and are difficult to implement in the clinic. In this work we present a maximum-likelihood expectation-maximization (MLEM) approach to the source reconstruction problem utilizing small fields and a simple experimental set-up. The MLEM algorithm iteratively ray-traces photons from the source plane to the exit plane and extracts corrections based on photon fluence profile measurements. The photon fluence profiles were determined by dose profile film measurements in air using a high density thin foil as build-up material and an appropriate point spread function (PSF). The effect of other beam parameters and scatter sources was minimized by using the smallest field size ([Formula: see text] cm(2)). The source occlusion effect was reproduced by estimating the position of the collimating jaws during this process. The method was first benchmarked against simulations for a range of typical accelerator source sizes. The sources were reconstructed with an accuracy better than 0.12?mm in the full width at half maximum (FWHM) to the respective electron sources incident on the target. The estimated jaw positions agreed within 0.2?mm with the expected values. The reconstruction technique was also tested against measurements on a Varian Novalis Tx linear accelerator and compared to a previously commissioned Monte Carlo model. The reconstructed FWHM of the source agreed within 0.03?mm and 0.11?mm to the commissioned electron source in the crossplane and inplane orientations respectively. The impact of the jaw positioning, experimental and PSF uncertainties on the reconstructed source distribution was evaluated with the former presenting the dominant effect. PMID:26758232

  5. Direct reconstruction of the source intensity distribution of a clinical linear accelerator using a maximum likelihood expectation maximization algorithm

    NASA Astrophysics Data System (ADS)

    Papaconstadopoulos, P.; Levesque, I. R.; Maglieri, R.; Seuntjens, J.

    2016-02-01

    Direct determination of the source intensity distribution of clinical linear accelerators is still a challenging problem for small field beam modeling. Current techniques most often involve special equipment and are difficult to implement in the clinic. In this work we present a maximum-likelihood expectation-maximization (MLEM) approach to the source reconstruction problem utilizing small fields and a simple experimental set-up. The MLEM algorithm iteratively ray-traces photons from the source plane to the exit plane and extracts corrections based on photon fluence profile measurements. The photon fluence profiles were determined by dose profile film measurements in air using a high density thin foil as build-up material and an appropriate point spread function (PSF). The effect of other beam parameters and scatter sources was minimized by using the smallest field size (0.5× 0.5 cm2). The source occlusion effect was reproduced by estimating the position of the collimating jaws during this process. The method was first benchmarked against simulations for a range of typical accelerator source sizes. The sources were reconstructed with an accuracy better than 0.12 mm in the full width at half maximum (FWHM) to the respective electron sources incident on the target. The estimated jaw positions agreed within 0.2 mm with the expected values. The reconstruction technique was also tested against measurements on a Varian Novalis Tx linear accelerator and compared to a previously commissioned Monte Carlo model. The reconstructed FWHM of the source agreed within 0.03 mm and 0.11 mm to the commissioned electron source in the crossplane and inplane orientations respectively. The impact of the jaw positioning, experimental and PSF uncertainties on the reconstructed source distribution was evaluated with the former presenting the dominant effect.

  6. Recursive expectation-maximization clustering: A method for identifying buffering mechanisms composed of phenomic modules

    NASA Astrophysics Data System (ADS)

    Guo, Jingyu; Tian, Dehua; McKinney, Brett A.; Hartman, John L.

    2010-06-01

    Interactions between genetic and/or environmental factors are ubiquitous, affecting the phenotypes of organisms in complex ways. Knowledge about such interactions is becoming rate-limiting for our understanding of human disease and other biological phenomena. Phenomics refers to the integrative analysis of how all genes contribute to phenotype variation, entailing genome and organism level information. A systems biology view of gene interactions is critical for phenomics. Unfortunately the problem is intractable in humans; however, it can be addressed in simpler genetic model systems. Our research group has focused on the concept of genetic buffering of phenotypic variation, in studies employing the single-cell eukaryotic organism, S. cerevisiae. We have developed a methodology, quantitative high throughput cellular phenotyping (Q-HTCP), for high-resolution measurements of gene-gene and gene-environment interactions on a genome-wide scale. Q-HTCP is being applied to the complete set of S. cerevisiae gene deletion strains, a unique resource for systematically mapping gene interactions. Genetic buffering is the idea that comprehensive and quantitative knowledge about how genes interact with respect to phenotypes will lead to an appreciation of how genes and pathways are functionally connected at a systems level to maintain homeostasis. However, extracting biologically useful information from Q-HTCP data is challenging, due to the multidimensional and nonlinear nature of gene interactions, together with a relative lack of prior biological information. Here we describe a new approach for mining quantitative genetic interaction data called recursive expectation-maximization clustering (REMc). We developed REMc to help discover phenomic modules, defined as sets of genes with similar patterns of interaction across a series of genetic or environmental perturbations. Such modules are reflective of buffering mechanisms, i.e., genes that play a related role in the maintenance of physiological homeostasis. To develop the method, 297 gene deletion strains were selected based on gene-drug interactions with hydroxyurea, an inhibitor of ribonucleotide reductase enzyme activity, which is critical for DNA synthesis. To partition the gene functions, these 297 deletion strains were challenged with growth inhibitory drugs known to target different genes and cellular pathways. Q-HTCP-derived growth curves were used to quantify all gene interactions, and the data were used to test the performance of REMc. Fundamental advantages of REMc include objective assessment of total number of clusters and assignment to each cluster a log-likelihood value, which can be considered an indicator of statistical quality of clusters. To assess the biological quality of clusters, we developed a method called gene ontology information divergence z-score (GOid_z). GOid_z summarizes total enrichment of GO attributes within individual clusters. Using these and other criteria, we compared the performance of REMc to hierarchical and K-means clustering. The main conclusion is that REMc provides distinct efficiencies for mining Q-HTCP data. It facilitates identification of phenomic modules, which contribute to buffering mechanisms that underlie cellular homeostasis and the regulation of phenotypic expression.

  7. An Expectation-Maximization Method for Spatio-Temporal Blind Source Separation Using an AR-MOG Source Model

    PubMed Central

    Hild, Kenneth E.; Attias, Hagai T.; Nagarajan, Srikantan S.

    2009-01-01

    In this paper, we develop a maximum-likelihood (ML) spatio-temporal blind source separation (BSS) algorithm, where the temporal dependencies are explained by assuming that each source is an autoregressive (AR) process and the distribution of the associated independent identically distributed (i.i.d.) inovations process is described using a mixture of Gaussians. Unlike most ML methods, the proposed algorithm takes into account both spatial and temporal information, optimization is performed using the expectation-maximization (EM) method, the source model is adapted to maximize the likelihood, and the update equations have a simple, analytical form. The proposed method, which we refer to as autoregressive mixture of Gaussians (AR-MOG), outperforms nine other methods for artificial mixtures of real audio. We also show results for using AR-MOG to extract the fetal cardiac signal from real magnetocardiographic (MCG) data. PMID:18334368

  8. OPTUM : Optimum Portfolio Tool for Utility Maximization documentation and user's guide.

    SciTech Connect

    VanKuiken, J. C.; Jusko, M. J.; Samsa, M. E.; Decision and Information Sciences

    2008-09-30

    The Optimum Portfolio Tool for Utility Maximization (OPTUM) is a versatile and powerful tool for selecting, optimizing, and analyzing portfolios. The software introduces a compact interface that facilitates problem definition, complex constraint specification, and portfolio analysis. The tool allows simple comparisons between user-preferred choices and optimized selections. OPTUM uses a portable, efficient, mixed-integer optimization engine (lp-solve) to derive the optimal mix of projects that satisfies the constraints and maximizes the total portfolio utility. OPTUM provides advanced features, such as convenient menus for specifying conditional constraints and specialized graphical displays of the optimal frontier and alternative solutions to assist in sensitivity visualization. OPTUM can be readily applied to other nonportfolio, resource-constrained optimization problems.

  9. Maternal Immunization Earlier in Pregnancy Maximizes Antibody Transfer and Expected Infant Seropositivity Against Pertussis

    PubMed Central

    Eberhardt, Christiane S.; Blanchard-Rohner, Geraldine; Lemaître, Barbara; Boukrid, Meriem; Combescure, Christophe; Othenin-Girard, Véronique; Chilin, Antonina; Petre, Jean; de Tejada, Begoña Martinez; Siegrist, Claire-Anne

    2016-01-01

    Background. Maternal immunization against pertussis is currently recommended after the 26th gestational week (GW). Data on the optimal timing of maternal immunization are inconsistent. Methods. We conducted a prospective observational noninferiority study comparing the influence of second-trimester (GW 13–25) vs third-trimester (≥GW 26) tetanus-diphtheria-acellular pertussis (Tdap) immunization in pregnant women who delivered at term. Geometric mean concentrations (GMCs) of cord blood antibodies to recombinant pertussis toxin (PT) and filamentous hemagglutinin (FHA) were assessed by enzyme-linked immunosorbent assay. The primary endpoint were GMCs and expected infant seropositivity rates, defined by birth anti-PT >30 enzyme-linked immunosorbent assay units (EU)/mL to confer seropositivity until 3 months of age. Results. We included 335 women (mean age, 31.0 ± 5.1 years; mean gestational age, 39.3 ± 1.3 GW) previously immunized with Tdap in the second (n = 122) or third (n = 213) trimester. Anti-PT and anti-FHA GMCs were higher following second- vs third-trimester immunization (PT: 57.1 EU/mL [95% confidence interval {CI}, 47.8–68.2] vs 31.1 EU/mL [95% CI, 25.7–37.7], P < .001; FHA: 284.4 EU/mL [95% CI, 241.3–335.2] vs 140.2 EU/mL [95% CI, 115.3–170.3], P < .001). The adjusted GMC ratios after second- vs third-trimester immunization differed significantly (PT: 1.9 [95% CI, 1.4–2.5]; FHA: 2.2 [95% CI, 1.7–3.0], P < .001). Expected infant seropositivity rates reached 80% vs 55% following second- vs third-trimester immunization (adjusted odds ratio, 3.7 [95% CI, 2.1–6.5], P < .001). Conclusions. Early second-trimester maternal Tdap immunization significantly increased neonatal antibodies. Recommending immunization from the second trimester onward would widen the immunization opportunity window and could improve seroprotection. PMID:26797213

  10. Expectancies, Utility Values, and Attributions for Performance in Mathematics.

    ERIC Educational Resources Information Center

    Heller, Kirby A.; And Others

    Some of the determinants of the decision to take or not to take mathematics are explored. The focus is on sex and grade differences in responses to questions about mathematics. The results show that fifth- and sixth-grade girls tended to have higher expectancies for success as well as higher ratings of their ability in mathematics than the boys…

  11. Crustacean hemolymph microbiota: Endemic, tightly controlled, and utilization expectable.

    PubMed

    Wang, Xian-Wei; Wang, Jin-Xing

    2015-12-01

    Increasing number of evidence suggests that the hemolymph of numerous apparently healthy invertebrates is unsterile. Investigation of hemolymph microbiota properties and the homeostasis between host and bacteria is helpful to reveal bacteria pathogenesis, host immunity, and possible utilization in disease control. Crustaceans represent a large family of aquatic animals. Therefore, crustacean fishery is of important economic value worldwide. Research related to crustacean hemolymph microbiota has been performed over the years. In the present study, we conclude currently available information and present a comprehensive analysis regarding homeostasis between host and bacteria. In general, the presence of microbiota in crustacean hemolymph is an endemic event and can be influenced by internal and external factors. Opportunistic bacteria may have generated some changes or mutations under hemolymph stress. Meanwhile, hosts suppress hemolymph microbiota proliferation with the help of some critical antimicrobial peptides and lectins. The hemolymph microbiota may be beneficial for hosts as resistance against external damages. In addition, the hemolymph microbiota may be utilized in aquaculture. PMID:26153452

  12. Fitting Nonlinear Ordinary Differential Equation Models with Random Effects and Unknown Initial Conditions Using the Stochastic Approximation Expectation-Maximization (SAEM) Algorithm.

    PubMed

    Chow, Sy-Miin; Lu, Zhaohua; Sherwood, Andrew; Zhu, Hongtu

    2016-03-01

    The past decade has evidenced the increased prevalence of irregularly spaced longitudinal data in social sciences. Clearly lacking, however, are modeling tools that allow researchers to fit dynamic models to irregularly spaced data, particularly data that show nonlinearity and heterogeneity in dynamical structures. We consider the issue of fitting multivariate nonlinear differential equation models with random effects and unknown initial conditions to irregularly spaced data. A stochastic approximation expectation-maximization algorithm is proposed and its performance is evaluated using a benchmark nonlinear dynamical systems model, namely, the Van der Pol oscillator equations. The empirical utility of the proposed technique is illustrated using a set of 24-h ambulatory cardiovascular data from 168 men and women. Pertinent methodological challenges and unresolved issues are discussed. PMID:25416456

  13. Patch-based augmentation of Expectation-Maximization for brain MRI tissue segmentation at arbitrary age after premature birth.

    PubMed

    Liu, Mengyuan; Kitsch, Averi; Miller, Steven; Chau, Vann; Poskitt, Kenneth; Rousseau, Francois; Shaw, Dennis; Studholme, Colin

    2016-02-15

    Accurate automated tissue segmentation of premature neonatal magnetic resonance images is a crucial task for quantification of brain injury and its impact on early postnatal growth and later cognitive development. In such studies it is common for scans to be acquired shortly after birth or later during the hospital stay and therefore occur at arbitrary gestational ages during a period of rapid developmental change. It is important to be able to segment any of these scans with comparable accuracy. Previous work on brain tissue segmentation in premature neonates has focused on segmentation at specific ages. Here we look at solving the more general problem using adaptations of age specific atlas based methods and evaluate this using a unique manually traced database of high resolution images spanning 20 gestational weeks of development. We examine the complimentary strengths of age specific atlas-based Expectation-Maximization approaches and patch-based methods for this problem and explore the development of two new hybrid techniques, patch-based augmentation of Expectation-Maximization with weighted fusion and a spatial variability constrained patch search. The former approach seeks to combine the advantages of both atlas- and patch-based methods by learning from the performance of the two techniques across the brain anatomy at different developmental ages, while the latter technique aims to use anatomical variability maps learnt from atlas training data to locally constrain the patch-based search range. The proposed approaches were evaluated using leave-one-out cross-validation. Compared with the conventional age specific atlas-based segmentation and direct patch based segmentation, both new approaches demonstrate improved accuracy in the automated labeling of cortical gray matter, white matter, ventricles and sulcal cortical-spinal fluid regions, while maintaining comparable results in deep gray matter. PMID:26702777

  14. Expected Utility Illustrated: A Graphical Analysis of Gambles with More than Two Possible Outcomes

    ERIC Educational Resources Information Center

    Chen, Frederick H.

    2010-01-01

    The author presents a simple geometric method to graphically illustrate the expected utility from a gamble with more than two possible outcomes. This geometric result gives economics students a simple visual aid for studying expected utility theory and enables them to analyze a richer set of decision problems under uncertainty compared to what

  15. Maximizing precipitation utilization in dryland agriculture in South Africa a review

    NASA Astrophysics Data System (ADS)

    Bennie, A. T. P.; Hensley, M.

    2001-01-01

    Agricultural systems in South Africa have been developed under primarily arid and semi-arid climatic conditions where droughts are common. Adoption of agricultural practices by farmers maximizes precipitation utilization, ensure production, economic and social sustainability. Precipitation use efficiency (PUE, kg produce ha -1 mm -1 rainfall plus the change in soil water content of the root zone) proved to be a valuable parameter for comparing the level of precipitation utilization of different production or management practices for dryland crop production or rangeland utilization. Increasing the length of the fallow period before planting increased the amount of pre-plant stored water in the soil thereby reducing the risk of drought damage to crops that resulted also in better yields. Deep drainage occurred only on sandy soils during wet seasons and values as high as 20% of the annual precipitation were measured during years of above average precipitation. In the experiments reported soil cultivation generally increased runoff. The retention of large amounts (>6 t ha -1) crop residue on the soil surface is required to decrease runoff from cultivated fields. Between 50 and 75% of the annual precipitation is lost through evaporation from the soil surface thus resulting in relatively low PUE-values.

  16. Novel hybrid GPU-CPU implementation of parallelized Monte Carlo parametric expectation maximization estimation method for population pharmacokinetic data analysis.

    PubMed

    Ng, C M

    2013-10-01

    The development of a population PK/PD model, an essential component for model-based drug development, is both time- and labor-intensive. A graphical-processing unit (GPU) computing technology has been proposed and used to accelerate many scientific computations. The objective of this study was to develop a hybrid GPU-CPU implementation of parallelized Monte Carlo parametric expectation maximization (MCPEM) estimation algorithm for population PK data analysis. A hybrid GPU-CPU implementation of the MCPEM algorithm (MCPEMGPU) and identical algorithm that is designed for the single CPU (MCPEMCPU) were developed using MATLAB in a single computer equipped with dual Xeon 6-Core E5690 CPU and a NVIDIA Tesla C2070 GPU parallel computing card that contained 448 stream processors. Two different PK models with rich/sparse sampling design schemes were used to simulate population data in assessing the performance of MCPEMCPU and MCPEMGPU. Results were analyzed by comparing the parameter estimation and model computation times. Speedup factor was used to assess the relative benefit of parallelized MCPEMGPU over MCPEMCPU in shortening model computation time. The MCPEMGPU consistently achieved shorter computation time than the MCPEMCPU and can offer more than 48-fold speedup using a single GPU card. The novel hybrid GPU-CPU implementation of parallelized MCPEM algorithm developed in this study holds a great promise in serving as the core for the next-generation of modeling software for population PK/PD analysis. PMID:24002801

  17. Expectation-maximization algorithm for determining natural selection of Y-linked genes through two-sex branching processes.

    PubMed

    Gonzlez, M; Gutirrez, C; Martnez, R

    2012-09-01

    A two-dimensional bisexual branching process has recently been presented for the analysis of the generation-to-generation evolution of the number of carriers of a Y-linked gene. In this model, preference of females for males with a specific genetic characteristic is assumed to be determined by an allele of the gene. It has been shown that the behavior of this kind of Y-linked gene is strongly related to the reproduction law of each genotype. In practice, the corresponding offspring distributions are usually unknown, and it is necessary to develop their estimation theory in order to determine the natural selection of the gene. Here we deal with the estimation problem for the offspring distribution of each genotype of a Y-linked gene when the only observable data are each generation's total numbers of males of each genotype and of females. We set out the problem in a non parametric framework and obtain the maximum likelihood estimators of the offspring distributions using an expectation-maximization algorithm. From these estimators, we also derive the estimators for the reproduction mean of each genotype and forecast the distribution of the future population sizes. Finally, we check the accuracy of the algorithm by means of a simulation study. PMID:22924631

  18. Utilization of Extended Donor Criteria Liver Allografts Maximizes Donor Use and Patient Access to Liver Transplantation

    PubMed Central

    Renz, John F.; Kin, Cindy; Kinkhabwala, Milan; Jan, Dominique; Varadarajan, Rhaghu; Goldstein, Michael; Brown, Robert; Emond, Jean C.

    2005-01-01

    Objective: The objective of this study was to evaluate the effect of systematic utilization of extended donor criteria liver allografts (EDC), including living donor allografts (LDLT), on patient access to liver transplantation (LTX). Summary Background Data: Utilization of liver allografts that do not meet traditional donor criteria (EDC) offer immediate expansion of the donor pool. EDC are typically allocated by transplant center rather than regional wait-list priority (RA). This single-institution series compares outcomes of EDC and RA allocation to determine the impact of EDC utilization on donor use and patient access to LTX. Methods: The authors conducted a retrospective analysis of 99 EDC recipients (49 deceased donor, 50 LDLT) and 116 RA recipients from April 2001 through April 2004. Deceased-donor EDC included: age >65 years, donation after cardiac death, positive viral serology (hepatitis C, hepatitis B core antibody, human T-cell lymphotrophic), split-liver, hypernatremia, prior carcinoma, steatosis, and behavioral high-risk donors. Outcome variables included patient and graft survival, hospitalization, initial graft function, and complication categorized as: biliary, vascular, wound, and other. Results: EDC recipients were more frequently diagnosed with hepatitis C virus or hepatocellular carcinoma and had a lower model for end-stage liver disease (MELD) score at LTX (P < 0.01). Wait-time, technical complications, and hospitalization were comparable. Log-rank analysis of Kaplan-Meier survival estimates demonstrated no difference in patient or graft survival; however, deaths among deceased-donor EDC recipients were frequently the result of patient comorbidities, whereas LDLT and RA deaths resulted from graft failure (P < 0.01). EDC increased patient access to LTX by 77% and reduced pre-LTX mortality by over 50% compared with regional data (P < 0.01). Conclusion: Systematic EDC utilization maximizes donor use, increases access to LTX, and significantly reduces wait-list mortality by providing satisfactory outcomes to select recipients. PMID:16192816

  19. The fistula elevation procedure: a valuable technique for maximizing arteriovenous fistula utilization.

    PubMed

    Cull, David L; Taylor, Spence M; Carsten, Christopher G; Youkey, Jerry R; Snyder, Bruce A; Sullivan, Timothy M; Langan, Eugene M

    2002-01-01

    Many patients are not considered candidates for radiocephalic fistula (RCF) or brachiocephalic fistula (BCF) creation or have fistulas that do not mature because the cephalic vein is too deep or tortuous to be accessed. Other patients have not been candidates for the basilic vein transposition (BVT) because limited length of adequate caliber vein precludes subcutaneous tunneling of the vein. In an effort to maximize arteriovenous fistula (AVF) utilization, we developed an adjunctive procedure designed to make the deep or tortuous fistula accessible to needle cannulation. The fistula elevation procedure (FEP) involves mobilization of the fistula, approximation of the subcutaneous tissue beneath the fistula, and subcuticular skin closure over the fistula. The procedure enhances the accessibility of the fistula by placing it in a more superficial position. The overlying cicatrix also acts as a guide for dialysis needle insertion. Between June 1998 and January 2001, 45 patients underwent a natural AVF that could not be accessed secondary to venous depth, tortuosity, or length. In each case, a FEP was performed to salvage the fistula. The FEP was performed as an adjunct to a BCF in 20 patients, a RCF in 7 patients, and a BVT in 8 patients. The FEP is a simple procedure that enhances AVF utilization by making the fistula more accessible to dialysis needle cannulation. The procedure is particularly helpful in obese patients who would not traditionally be considered candidates for natural AVF creation. PMID:11904810

  20. Profit-maximizing utilization of transmission and storage capacity by a regulated natural gas pipeline firm

    SciTech Connect

    Schell, L.S.

    1988-01-01

    This thesis examines how regulation-induced economic changes alter the intra-annual pattern of transmission and storage-capacity utilization by a profit-maximizing natural gas pipeline firm. The pipeline firm must meet the stochastic and seasonally volatile demand of firm sales customers and (firm) transportation customers. Interruptible sales demand is assumed nonseasonal. Aggregate demand is satisfied using existing transmission and storage capacity. A theoretical model is developed to derive a general rule for intertemporal storage of natural gas between any two periods of the short-term, planning horizon. The model incorporates a modified average-cost (MAC) pricing scheme that represents the rate making process. The pipeline firm is allowed limited flexibility in discounting interruptible rates. Discounting results in a nonlinear objective function because the quantity of interruptible sales is price-determined. The constraint set is linear. An applied model is constructed based on the theoretical model and the MAC pricing scheme. Results indicate that changing the wellhead prices trajectory has a significant impact on transmission and storage utilization.

  1. Comparison of ordered subsets expectation maximization and Chang's attenuation correction method in quantitative cardiac SPET: a phantom study.

    PubMed

    Dey, D; Slomka, P J; Hahn, L J; Kloiber, R

    1998-12-01

    Photon attenuation is one of the primary causes of artifacts in cardiac single photon emission tomography (SPET). Several attenuation correction algorithms have been proposed. The aim of this study was to compare the effect of using the ordered subsets expectation maximization (OSEM) reconstruction algorithm and Chang's non-uniform attenuation correction method on quantitative cardiac SPET. We performed SPET scans of an anthropomorphic phantom simulating normal and abnormal myocardial studies. Attenuation maps of the phantom were obtained from computed tomographic images. The SPET projection data were corrected for attenuation using OSEM reconstruction, as well as Chang's method. For each defect scan and attenuation correction method, we calculated three quantitative parameters: average radial maximum (ARM) ratio of the defect-to-normal area, maximum defect contrast (MDC) and defect volume, using automated three-dimensional quantitation. The differences between the two methods were less than 4% for defect-to-normal ARM ratio, 19% for MDC and 13% for defect volume. These differences are within the range of estimated statistical variation of SPET. The calculation times of the two methods were comparable. For all SPET studies, OSEM attenuation correction gave a more correct activity distribution, with respect to both the homogeneity of the radiotracer and the shape of the cardiac insert. The difference in uniformity between OSEM and Chang's method was quantified by segmental analysis and found to be less than 8% for the normal study. In conclusion, OSEM and Chang's attenuation correction are quantitatively equivalent, with comparable calculation times. OSEM reconstruction gives a more correct activity distribution and is therefore preferred. PMID:9885805

  2. Expectation-maximization algorithms for learning a finite mixture of univariate survival time distributions from partially specified class values

    SciTech Connect

    Lee, Youngrok

    2013-05-15

    Heterogeneity exists on a data set when samples from di#11;erent classes are merged into the data set. Finite mixture models can be used to represent a survival time distribution on heterogeneous patient group by the proportions of each class and by the survival time distribution within each class as well. The heterogeneous data set cannot be explicitly decomposed to homogeneous subgroups unless all the samples are precisely labeled by their origin classes; such impossibility of decomposition is a barrier to overcome for estimating #12;nite mixture models. The expectation-maximization (EM) algorithm has been used to obtain maximum likelihood estimates of #12;nite mixture models by soft-decomposition of heterogeneous samples without labels for a subset or the entire set of data. In medical surveillance databases we can find partially labeled data, that is, while not completely unlabeled there is only imprecise information about class values. In this study we propose new EM algorithms that take advantages of using such partial labels, and thus incorporate more information than traditional EM algorithms. We particularly propose four variants of the EM algorithm named EM-OCML, EM-PCML, EM-HCML and EM-CPCML, each of which assumes a specific mechanism of missing class values. We conducted a simulation study on exponential survival trees with five classes and showed that the advantages of incorporating substantial amount of partially labeled data can be highly signi#12;cant. We also showed model selection based on AIC values fairly works to select the best proposed algorithm on each specific data set. A case study on a real-world data set of gastric cancer provided by Surveillance, Epidemiology and End Results (SEER) program showed a superiority of EM-CPCML to not only the other proposed EM algorithms but also conventional supervised, unsupervised and semi-supervised learning algorithms.

  3. The role of data assimilation in maximizing the utility of geospace observations (Invited)

    NASA Astrophysics Data System (ADS)

    Matsuo, T.

    2013-12-01

    Data assimilation can facilitate maximizing the utility of existing geospace observations by offering an ultimate marriage of inductive (data-driven) and deductive (first-principles based) approaches to addressing critical questions in space weather. Assimilative approaches that incorporate dynamical models are, in particular, capable of making a diverse set of observations consistent with physical processes included in a first-principles model, and allowing unobserved physical states to be inferred from observations. These points will be demonstrated in the context of the application of an ensemble Kalman filter (EnKF) to a thermosphere and ionosphere general circulation model. An important attribute of this approach is that the feedback between plasma and neutral variables is self-consistently treated both in the forecast model as well as in the assimilation scheme. This takes advantage of the intimate coupling between the thermosphere and ionosphere described in general circulation models to enable the inference of unobserved thermospheric states from the relatively plentiful observations of the ionosphere. Given the ever-growing infrastructure for the global navigation satellite system, this is indeed a promising prospect for geospace data assimilation. In principle, similar approaches can be applied to any geospace observing systems to extract more geophysical information from a given set of observations than would otherwise be possible.

  4. MaxBin: an automated binning method to recover individual genomes from metagenomes using an expectation-maximization algorithm

    PubMed Central

    2014-01-01

    Background Recovering individual genomes from metagenomic datasets allows access to uncultivated microbial populations that may have important roles in natural and engineered ecosystems. Understanding the roles of these uncultivated populations has broad application in ecology, evolution, biotechnology and medicine. Accurate binning of assembled metagenomic sequences is an essential step in recovering the genomes and understanding microbial functions. Results We have developed a binning algorithm, MaxBin, which automates the binning of assembled metagenomic scaffolds using an expectation-maximization algorithm after the assembly of metagenomic sequencing reads. Binning of simulated metagenomic datasets demonstrated that MaxBin had high levels of accuracy in binning microbial genomes. MaxBin was used to recover genomes from metagenomic data obtained through the Human Microbiome Project, which demonstrated its ability to recover genomes from real metagenomic datasets with variable sequencing coverages. Application of MaxBin to metagenomes obtained from microbial consortia adapted to grow on cellulose allowed genomic analysis of new, uncultivated, cellulolytic bacterial populations, including an abundant myxobacterial population distantly related to Sorangium cellulosum that possessed a much smaller genome (5 MB versus 13 to 14 MB) but has a more extensive set of genes for biomass deconstruction. For the cellulolytic consortia, the MaxBin results were compared to binning using emergent self-organizing maps (ESOMs) and differential coverage binning, demonstrating that it performed comparably to these methods but had distinct advantages in automation, resolution of related genomes and sensitivity. Conclusions The automatic binning software that we developed successfully classifies assembled sequences in metagenomic datasets into recovered individual genomes. The isolation of dozens of species in cellulolytic microbial consortia, including a novel species of myxobacteria that has the smallest genome among all sequenced aerobic myxobacteria, was easily achieved using the binning software. This work demonstrates that the processes required for recovering genomes from assembled metagenomic datasets can be readily automated, an important advance in understanding the metabolic potential of microbes in natural environments. MaxBin is available at https://sourceforge.net/projects/maxbin/. PMID:25136443

  5. Maximizing coupling-efficiency of high-power diode lasers utilizing hybrid assembly technology

    NASA Astrophysics Data System (ADS)

    Zontar, D.; Dogan, M.; Fulghum, S.; Müller, T.; Haag, S.; Brecher, C.

    2015-03-01

    In this paper, we present hybrid assembly technology to maximize coupling efficiency for spatially combined laser systems. High quality components, such as center-turned focusing units, as well as suitable assembly strategies are necessary to obtain highest possible output ratios. Alignment strategies are challenging tasks due to their complexity and sensitivity. Especially in low-volume production fully automated systems are economically at a disadvantage, as operator experience is often expensive. However reproducibility and quality of automatically assembled systems can be superior. Therefore automated and manual assembly techniques are combined to obtain high coupling efficiency while preserving maximum flexibility. The paper will describe necessary equipment and software to enable hybrid assembly processes. Micromanipulator technology with high step-resolution and six degrees of freedom provide a large number of possible evaluation points. Automated algorithms are necess ary to speed-up data gathering and alignment to efficiently utilize available granularity for manual assembly processes. Furthermore, an engineering environment is presented to enable rapid prototyping of automation tasks with simultaneous data ev aluation. Integration with simulation environments, e.g. Zemax, allows the verification of assembly strategies in advance. Data driven decision making ensures constant high quality, documents the assembly process and is a basis for further improvement. The hybrid assembly technology has been applied on several applications for efficiencies above 80% and will be discussed in this paper. High level coupling efficiency has been achieved with minimized assembly as a result of semi-automated alignment. This paper will focus on hybrid automation for optimizing and attaching turning mirrors and collimation lenses.

  6. Putting Teens at the Center: Maximizing Public Utility of Urban Space through Youth Involvement in Planning and Employment.

    ERIC Educational Resources Information Center

    Lawson, Laura; McNally, Marcia

    1995-01-01

    Including teens' needs in the planning and maintenance of urban space suggests new methods of layering utility and maximizing benefit to teens and community. Discusses the Berkeley Youth Alternatives (BYA) Youth Employment Landscape Program and BYA Community Garden Patch. Program descriptions and evaluation provide future direction. (LZ)

  7. The behavioral economics of consumer brand choice: patterns of reinforcement and utility maximization.

    PubMed

    Foxall, Gordon R; Oliveira-Castro, Jorge M; Schrezenmaier, Teresa C

    2004-06-30

    Purchasers of fast-moving consumer goods generally exhibit multi-brand choice, selecting apparently randomly among a small subset or "repertoire" of tried and trusted brands. Their behavior shows both matching and maximization, though it is not clear just what the majority of buyers are maximizing. Each brand attracts, however, a small percentage of consumers who are 100%-loyal to it during the period of observation. Some of these are exclusively buyers of premium-priced brands who are presumably maximizing informational reinforcement because their demand for the brand is relatively price-insensitive or inelastic. Others buy exclusively the cheapest brands available and can be assumed to maximize utilitarian reinforcement since their behavior is particularly price-sensitive or elastic. Between them are the majority of consumers whose multi-brand buying takes the form of selecting a mixture of economy -- and premium-priced brands. Based on the analysis of buying patterns of 80 consumers for 9 product categories, the paper examines the continuum of consumers so defined and seeks to relate their buying behavior to the question of how and what consumers maximize. PMID:15157975

  8. 76 FR 37376 - Guidelines for Ensuring and Maximizing the Quality, Objectivity, Utility, and Integrity of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-27

    ... Management and Budget (67 FR 8452-8460), pursuant to section 515 of the Treasury and General Government... FR 8452-8460) that direct each federal agency to (1) Issue its own guidelines ensuring and maximizing... Environmental Quality, the Secretary of the Smithsonian Institution, the Director of the National...

  9. Social and Professional Participation of Individuals Who Are Deaf: Utilizing the Psychosocial Potential Maximization Framework

    ERIC Educational Resources Information Center

    Jacobs, Paul G.; Brown, P. Margaret; Paatsch, Louise

    2012-01-01

    This article documents a strength-based understanding of how individuals who are deaf maximize their social and professional potential. This exploratory study was conducted with 49 adult participants who are deaf (n = 30) and who have typical hearing (n = 19) residing in America, Australia, England, and South Africa. The findings support a

  10. Social and Professional Participation of Individuals Who Are Deaf: Utilizing the Psychosocial Potential Maximization Framework

    ERIC Educational Resources Information Center

    Jacobs, Paul G.; Brown, P. Margaret; Paatsch, Louise

    2012-01-01

    This article documents a strength-based understanding of how individuals who are deaf maximize their social and professional potential. This exploratory study was conducted with 49 adult participants who are deaf (n = 30) and who have typical hearing (n = 19) residing in America, Australia, England, and South Africa. The findings support a…

  11. Effects of hyperoxia on maximal leg O2 supply and utilization in men.

    PubMed

    Knight, D R; Schaffartzik, W; Poole, D C; Hogan, M C; Bebout, D E; Wagner, P D

    1993-12-01

    We studied O2 transport in the leg to determine if hyperoxia will increase the maximal rate of O2 uptake (VO2max) in exercising muscle. An increase in inspired O2 fraction (FIO2) from 0.21 to 1.00 was postulated to have the following effects: 1) increase the leg VO2max by approximately 5-10%, 2) increase the maximal O2 delivery [arterial O2 concentration.flow (CaO2.Q] by approximately 10%, and 3) raise the leg VO2max in proportion to both the femoral venous PO2 and mean leg capillary PO2. To test these hypotheses, 11 men performed cycle exercise to the highest work rates (WRmax) they could achieve while breathing 100% O2 (hyperoxia), 21% O2 (normoxia), and 12% O2 (hypoxia). Leg VO2 was derived from duplicate measurements of femoral venous blood flow and CaO2 and femoral venous blood O2 concentrations (CVO2) at 20, 35, 50, 92, and 100% WRmax in each FIO2. Femoral venous leg Q (Qleg) was measured by the constant-infusion thermodilution technique, and leg O2 uptake (VO2) was determined by the Fick principle [VO2 = Qleg(CaO2-CVO2)]. Leg VO2max was the mean of duplicate values of VO2 at 100% WRmax for each FIO2. Hyperoxia increased leg VO2max by 8.1% (P = 0.016) and maximal O2 delivery by 10.9% (P = 0.05) without changing Qleg. There was a significant increase in femoral venous PO2 (P < 0.001) that was proportionally greater than the increase in leg VO2max. The results support our first and second hypotheses, providing direct evidence that in normal subjects leg VO2max is limited by O2 supply during normoxia.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8125878

  12. People believe each other to be selfish hedonic maximizers.

    PubMed

    De Vito, Stefania; Bonnefon, Jean-François

    2014-10-01

    Current computational models of theory of mind typically assume that humans believe each other to selfishly maximize utility, for a conception of utility that makes it indistinguishable from personal gains. We argue that this conception is at odds with established facts about human altruism, as well as the altruism that humans expect from each other. We report two experiments showing that people expect other agents to selfishly maximize their pleasure, even when these other agents behave altruistically. Accordingly, defining utility as pleasure permits us to reconcile the assumption that humans expect each other to selfishly maximize utility with the fact that humans expect each other to behave altruistically. PMID:24519484

  13. Optimal Decision-Making of Countermeasures by Estimating Their Expected Utilities

    NASA Astrophysics Data System (ADS)

    Park, So Ryoung; Noh, Sanguk

    This paper investigates the autonomous decision-making process of the selection of alternative countermeasures against threats in electronic warfare settings. We introduce a threat model, which represents a specific threat pattern, and a methodology that decides the best countermeasure against real-time threats using the decision theory. To determine the optimal countermeasure, we model the probabilities of the effects of countermeasures, if executed, and combine the probabilities with their utilities. This methodology based upon the inductive threat model calculates the expected utilities of countermeasures which are applicable given a situation, and provide an intelligent command and control agent with the best countermeasure to threats. We present empirical results that demonstrate the agent's capabilities of choosing countermeasures to threats in simulated electronic warfare settings.

  14. Single-atom catalysis in mesoporous photovoltaics: the principle of utility maximization.

    PubMed

    Shi, Yantao; Zhao, Chunyu; Wei, Haisheng; Guo, Jiahao; Liang, Suxia; Wang, Aiqin; Zhang, Tao; Liu, Jingyue; Ma, Tingli

    2014-12-23

    FeOx -supported single Pt atoms are used for the first time as counter electrodes (CEs) in dye-sensitized solar cells (DSCs), which are mesoporous photovoltaic devices. This system enables the investigation of the electrocatalytic behavior of a single-atom catalyst (SAC). Compared with conventional Pt CEs, the SAC-based CEs exhibit better reversibility as indicated by the peak-to-peak separation (Epp ). A high degree of atom utilization is demonstrated. PMID:25312028

  15. Maximizing the clinical utility of antimllerian hormone testing in women's health

    PubMed Central

    Leader, Benjamin; Baker, Valerie L.

    2014-01-01

    Purpose of review To provide an update on the latest clinical applications of serum antimllerian hormone (AMH) testing with practical approaches to mitigate the impact of significant variability in AMH results. Recent findings Recent studies continue to demonstrate that AMH is the best single serum test for ovarian response management with, at most, a weak-to-moderate age-independent association with live-birth rate and time to conception. Data confirm serum AMH levels improve menopause prediction, monitoring of ovarian damage, and identification of women at risk for several ovary-related disorders such as polycystic ovary syndrome and premature or primary ovarian insufficiency. However, it is now recognized that serum AMH results can have dramatic variability due to common, biologic fluctuations within some individuals, use of hormonal contraceptives or other medications, certain surgical procedures, specimen treatment, assay changes, and laboratory calibration differences. Practical guidelines are provided to minimize the impact of variability in AMH results and maximize the accuracy of clinical decision-making. Summary AMH is an ovarian biomarker of central importance which improves the clinical management of women's health. However, with the simultaneous rapid expansion of AMH clinical applications and recognition of variability in AMH results, consensus regarding the clinical cutpoints is increasingly difficult. Therefore, a careful approach to AMH measurement and interpretation in clinical care is essential. PMID:24978853

  16. Maximizing Utility for Ares V - Unpressurized Cargo and Secondary Missions for Heliocentric Observations

    NASA Astrophysics Data System (ADS)

    Gonzales, Andrew; Mink, Ronald; Khazanov, George

    2010-05-01

    Heliophysics seeks to understand the influence of the Sun throughout the solar system and, in particular, its connection to the Earth and the Earth's extended space environment. The launch vehicle options for heliophysics missions have been reduced over recent years, causing the implementation of many proposed missions to be no longer viable. The current near-term launch options for future heliophysics missions limit the capability and frequency of missions. A recent NASA study has identified a means of accommodating Unpressurized Caro (UPC) on Ares V in addition to the primary lander payload. The UPC study included systems, mechanical, thermal and avionics engineering as well as the definition of preliminary concepts of operation. Preliminary trajectory studies were completed to understand the capability of UPC payloads on the Ares V to reach multiple inner solar system destinations, including missions that perform heliocentric observations. Requirements for including the capability to launch UPC payloads from Ares V are being developed for the Constellation Program This work expands the utility of the United States' next generation of Heavy Lift launch vehicles. Heliocentric mission planners will be able to receive early data and open up communications channels to utilize these new and expanded UPC services.

  17. Maximizing the utility of monitoring to the adaptive management of natural resources

    USGS Publications Warehouse

    Kendall, William L.; Moore, Clinton T.

    2012-01-01

    Data collection is an important step in any investigation about the structure or processes related to a natural system. In a purely scientific investigation (experiments, quasi-experiments, observational studies), data collection is part of the scientific method, preceded by the identification of hypotheses and the design of any manipulations of the system to test those hypotheses. Data collection and the manipulations that precede it are ideally designed to maximize the information that is derived from the study. That is, such investigations should be designed for maximum power to evaluate the relative validity of the hypotheses posed. When data collection is intended to inform the management of ecological systems, we call it monitoring. Note that our definition of monitoring encompasses a broader range of data-collection efforts than some alternative definitions – e.g. Chapter 3. The purpose of monitoring as we use the term can vary, from surveillance or “thumb on the pulse” monitoring (see Nichols and Williams 2006), intended to detect changes in a system due to any non-specified source (e.g. the North American Breeding Bird Survey), to very specific and targeted monitoring of the results of specific management actions (e.g. banding and aerial survey efforts related to North American waterfowl harvest management). Although a role of surveillance monitoring is to detect unanticipated changes in a system, the same result is possible from a collection of targeted monitoring programs distributed across the same spatial range (Box 4.1). In the face of limited budgets and many specific management questions, tying monitoring as closely as possible to management needs is warranted (Nichols and Williams 2006). Adaptive resource management (ARM; Walters 1986, Williams 1997, Kendall 2001, Moore and Conroy 2006, McCarthy and Possingham 2007, Conroy et al. 2008a) provides a context and specific purpose for monitoring: to evaluate decisions with respect to achievement of specific management objectives; and to evaluate the relative validity of predictive system models. This latter purpose is analogous to the role of data collection within the scientific method, in a research context.

  18. A Neurodynamic Approach for Real-Time Scheduling via Maximizing Piecewise Linear Utility.

    PubMed

    Guo, Zhishan; Baruah, Sanjoy K

    2016-02-01

    In this paper, we study a set of real-time scheduling problems whose objectives can be expressed as piecewise linear utility functions. This model has very wide applications in scheduling-related problems, such as mixed criticality, response time minimization, and tardiness analysis. Approximation schemes and matrix vectorization techniques are applied to transform scheduling problems into linear constraint optimization with a piecewise linear and concave objective; thus, a neural network-based optimization method can be adopted to solve such scheduling problems efficiently. This neural network model has a parallel structure, and can also be implemented on circuits, on which the converging time can be significantly limited to meet real-time requirements. Examples are provided to illustrate how to solve the optimization problem and to form a schedule. An approximation ratio bound of 0.5 is further provided. Experimental studies on a large number of randomly generated sets suggest that our algorithm is optimal when the set is nonoverloaded, and outperforms existing typical scheduling strategies when there is overload. Moreover, the number of steps for finding an approximate solution remains at the same level when the size of the problem (number of jobs within a set) increases. PMID:26336153

  19. Utilization of negative beat-frequencies for maximizing the update-rate of OFDR

    NASA Astrophysics Data System (ADS)

    Gabai, Haniel; Botsev, Yakov; Hahami, Meir; Eyal, Avishay

    2015-07-01

    In traditional OFDR systems, the backscattered profile of a sensing fiber is inefficiently duplicated to the negative band of spectrum. In this work, we present a new OFDR design and algorithm that remove this redundancy and make use of negative beat frequencies. In contrary to conventional OFDR designs, it facilitates efficient use of the available system bandwidth and enables distributed sensing with the maximum allowable interrogation update-rate for a given fiber length. To enable the reconstruction of negative beat frequencies an I/Q type receiver is used. In this receiver, both the in-phase (I) and quadrature (Q) components of the backscatter field are detected. Following detection, both components are digitally combined to produce a complex backscatter signal. Accordingly, due to its asymmetric nature, the produced spectrum will not be corrupted by the appearance of negative beat-frequencies. Here, via a comprehensive computer simulation, we show that in contrast to conventional OFDR systems, I/Q OFDR can be operated at maximum interrogation update-rate for a given fiber length. In addition, we experimentally demonstrate, for the first time, the ability of I/Q OFDR to utilize negative beat-frequencies for long-range distributed sensing.

  20. Nonlinear spatio-temporal filtering of dynamic PET data using a four-dimensional Gaussian filter and expectation-maximization deconvolution

    NASA Astrophysics Data System (ADS)

    Floberg, J. M.; Holden, J. E.

    2013-02-01

    We introduce a method for denoising dynamic PET data, spatio-temporal expectation-maximization (STEM) filtering, that combines four-dimensional Gaussian filtering with EM deconvolution. The initial Gaussian filter suppresses noise at a broad range of spatial and temporal frequencies and EM deconvolution quickly restores the frequencies most important to the signal. We aim to demonstrate that STEM filtering can improve variance in both individual time frames and in parametric images without introducing significant bias. We evaluate STEM filtering with a dynamic phantom study, and with simulated and human dynamic PET studies of a tracer with reversible binding behaviour, [C-11]raclopride, and a tracer with irreversible binding behaviour, [F-18]FDOPA. STEM filtering is compared to a number of established three and four-dimensional denoising methods. STEM filtering provides substantial improvements in variance in both individual time frames and in parametric images generated with a number of kinetic analysis techniques while introducing little bias. STEM filtering does bias early frames, but this does not affect quantitative parameter estimates. STEM filtering is shown to be superior to the other simple denoising methods studied. STEM filtering is a simple and effective denoising method that could be valuable for a wide range of dynamic PET applications.

  1. In vitro estimation of fast and slow wave parameters of thin trabecular bone using space-alternating generalized expectation-maximization algorithm.

    PubMed

    Grimes, Morad; Bouhadjera, Abdelmalek; Haddad, Sofiane; Benkedidah, Toufik

    2012-07-01

    In testing cancellous bone using ultrasound, two types of longitudinal Biot's waves are observed in the received signal. These are known as fast and slow waves and their appearance depend on the alignment of bone trabeculae in the propagation path and the thickness of the specimen under test (SUT). They can be used as an effective tool for the diagnosis of osteoporosis because wave propagation behavior depends on the bone structure. However, the identification of these waves in the received signal can be difficult to achieve. In this study, ultrasonic wave propagation in a 4mm thick bovine cancellous bone in the direction parallel to the trabecular alignment is considered. The observed Biot's fast and slow longitudinal waves are superimposed; which makes it difficult to extract any information from the received signal. These two waves can be separated using the space alternating generalized expectation maximization (SAGE) algorithm. The latter has been used mainly in speech processing. In this new approach, parameters such as, arrival time, center frequency, bandwidth, amplitude, phase and velocity of each wave are estimated. The B-Scan images and its associated A-scans obtained through simulations using Biot's finite-difference time-domain (FDTD) method are validated experimentally using a thin bone sample obtained from the femoral-head of a 30 months old bovine. PMID:22284937

  2. Unsupervised learning applied in MER and ECG signals through Gaussians mixtures with the Expectation-Maximization algorithm and Variational Bayesian Inference.

    PubMed

    Vargas Cardona, Hernn Daro; Orozco, lvaro ngel; lvarez, Mauricio A

    2013-01-01

    Automatic identification of biosignals is one of the more studied fields in biomedical engineering. In this paper, we present an approach for the unsupervised recognition of biomedical signals: Microelectrode Recordings (MER) and Electrocardiography signals (ECG). The unsupervised learning is based in classic and bayesian estimation theory. We employ gaussian mixtures models with two estimation methods. The first is derived from the frequentist estimation theory, known as Expectation-Maximization (EM) algorithm. The second is obtained from bayesian probabilistic estimation and it is called variational inference. In this framework, both methods are used for parameters estimation of Gaussian mixtures. The mixtures models are used for unsupervised pattern classification, through the responsibility matrix. The algorithms are applied in two real databases acquired in Parkinson's disease surgeries and electrocardiograms. The results show an accuracy over 85% in MER and 90% in ECG for identification of two classes. These results are statistically equal or even better than parametric (Naive Bayes) and nonparametric classifiers (K-nearest neighbor). PMID:24110690

  3. Illustrating Caffeine's Pharmacological and Expectancy Effects Utilizing a Balanced Placebo Design.

    ERIC Educational Resources Information Center

    Lotshaw, Sandra C.; And Others

    1996-01-01

    Hypothesizes that pharmacological and expectancy effects may be two principles that govern caffeine consumption in the same way they affect other drug use. Tests this theory through a balanced placebo design on 100 male undergraduate students. Expectancy set and caffeine content appeared equally powerful, and worked additionally, to affect…

  4. Illustrating Caffeine's Pharmacological and Expectancy Effects Utilizing a Balanced Placebo Design.

    ERIC Educational Resources Information Center

    Lotshaw, Sandra C.; And Others

    1996-01-01

    Hypothesizes that pharmacological and expectancy effects may be two principles that govern caffeine consumption in the same way they affect other drug use. Tests this theory through a balanced placebo design on 100 male undergraduate students. Expectancy set and caffeine content appeared equally powerful, and worked additionally, to affect

  5. Pt skin on AuCu intermetallic substrate: a strategy to maximize Pt utilization for fuel cells.

    PubMed

    Wang, Gongwei; Huang, Bing; Xiao, Li; Ren, Zhandong; Chen, Hao; Wang, Deli; Abrua, Hctor D; Lu, Juntao; Zhuang, Lin

    2014-07-01

    The dependence on Pt catalysts has been a major issue of proton-exchange membrane (PEM) fuel cells. Strategies to maximize the Pt utilization in catalysts include two main approaches: to put Pt atoms only at the catalyst surface and to further enhance the surface-specific catalytic activity (SA) of Pt. Thus far there has been no practical design that combines these two features into one single catalyst. Here we report a combined computational and experimental study on the design and implementation of Pt-skin catalysts with significantly improved SA toward the oxygen reduction reaction (ORR). Through screening, using density functional theory (DFT) calculations, a Pt-skin structure on AuCu(111) substrate, consisting of 1.5 monolayers of Pt, is found to have an appropriately weakened oxygen affinity, in comparison to that on Pt(111), which would be ideal for ORR catalysis. Such a structure is then realized by substituting the Cu atoms in three surface layers of AuCu intermetallic nanoparticles (AuCu iNPs) with Pt. The resulting Pt-skinned catalyst (denoted as Pt(S)AuCu iNPs) has been characterized in depth using synchrotron XRD, XPS, HRTEM, and HAADF-STEM/EDX, such that the Pt-skin structure is unambiguously identified. The thickness of the Pt skin was determined to be less than two atomic layers. Finally the catalytic activity of Pt(S)AuCu iNPs toward the ORR was measured via rotating disk electrode (RDE) voltammetry through which it was established that the SA was more than 2 times that of a commercial Pt/C catalyst. Taking into account the ultralow Pt loading in Pt(S)AuCu iNPs, the mass-specific catalytic activity (MA) was determined to be 0.56 A/mg(Pt)@0.9 V, a value that is well beyond the DOE 2017 target for ORR catalysts (0.44 A/mg(Pt)@0.9 V). These findings provide a strategic design and a realizable approach to high-performance and Pt-efficient catalysts for fuel cells. PMID:24936859

  6. Reader variability in mammography and its implications for expected utility over the population of readers and cases.

    PubMed

    Wagner, Robert F; Beam, Craig A; Beiden, Sergey V

    2004-01-01

    The multiple-reader, multiple-case (MRMC) approach to receiver operating characteristic (ROC) analysis is becoming the dominant assessment paradigm in medical imaging. Its most common version involves having many readers read every patient case in the study, a critical feature since differences among competing imaging modalities are often dominated by differences in reader performance. The present authors have carried out MRMC ROC analysis on a uniquely large data set for mammography. The analysis quantifies the great range of observed reader skill in that data set. It also demonstrates that the sample sizes are sufficiently large that the conclusions generalize to the populations sampled here with little uncertainty from the finite sample size. A schematic approach to bracketing the utility matrix is then used to study trends in the resulting expected utility functions that correspond to the range of observed ROC curves. This is done for both the screening and the diagnostic context. The results raise 2 hypotheses for further investigation. First, it is possible that the present ambiguity surrounding the effectiveness of mammography is due in part to the observed range of reader skills and corresponding expected utility functions. Second, it is possible that computer-assisted modalities for mammography may lead to improvements in the expected utility function not only for screening but also in the diagnostic context, especially for the lower performing readers. PMID:15534338

  7. GUIDELINES FOR ENSURING AND MAXIMIZING THE QUALITY, OBJECTIVITY, UTILITY, AND INTEGRITY OF INFORMATION DISSEMINATED BY THE ENVIRONMENTAL PROTECTION AGENCY

    EPA Science Inventory

    Developed in response to guidelines issued by the Office of Management and Budget (OMB)1 under Section 515(a) of the Treasury and General Government Appropriations Act for Fiscal Year 2001 (Public Law 106-554; H.R. 5658), the Guidelines for Ensuring and Maximizing the Quality, Ob...

  8. Expectant Mothers Maximizing Opportunities: Maternal Characteristics Moderate Multifactorial Prenatal Stress in the Prediction of Birth Weight in a Sample of Children Adopted at Birth

    PubMed Central

    Brotnow, Line; Reiss, David; Stover, Carla S.; Ganiban, Jody; Leve, Leslie D.; Neiderhiser, Jenae M.; Shaw, Daniel S.; Stevens, Hanna E.

    2015-01-01

    Background Mothers’ stress in pregnancy is considered an environmental risk factor in child development. Multiple stressors may combine to increase risk, and maternal personal characteristics may offset the effects of stress. This study aimed to test the effect of 1) multifactorial prenatal stress, integrating objective “stressors” and subjective “distress” and 2) the moderating effects of maternal characteristics (perceived social support, self-esteem and specific personality traits) on infant birthweight. Method Hierarchical regression modeling was used to examine cross-sectional data on 403 birth mothers and their newborns from an adoption study. Results Distress during pregnancy showed a statistically significant association with birthweight (R2 = 0.032, F(2, 398) = 6.782, p = .001). The hierarchical regression model revealed an almost two-fold increase in variance of birthweight predicted by stressors as compared with distress measures (R2Δ = 0.049, F(4, 394) = 5.339, p < .001). Further, maternal characteristics moderated this association (R2Δ = 0.031, F(4, 389) = 3.413, p = .009). Specifically, the expected benefit to birthweight as a function of higher SES was observed only for mothers with lower levels of harm-avoidance and higher levels of perceived social support. Importantly, the results were not better explained by prematurity, pregnancy complications, exposure to drugs, alcohol or environmental toxins. Conclusions The findings support multidimensional theoretical models of prenatal stress. Although both objective stressors and subjectively measured distress predict birthweight, they should be considered distinct and cumulative components of stress. This study further highlights that jointly considering risk factors and protective factors in pregnancy improves the ability to predict birthweight. PMID:26544958

  9. Image reconstruction of single photon emission computed tomography (SPECT) on a pebble bed reactor (PBR) using expectation maximization and exact inversion algorithms: Comparison study by means of numerical phantom

    NASA Astrophysics Data System (ADS)

    Razali, Azhani Mohd; Abdullah, Jaafar

    2015-04-01

    Single Photon Emission Computed Tomography (SPECT) is a well-known imaging technique used in medical application, and it is part of medical imaging modalities that made the diagnosis and treatment of disease possible. However, SPECT technique is not only limited to the medical sector. Many works are carried out to adapt the same concept by using high-energy photon emission to diagnose process malfunctions in critical industrial systems such as in chemical reaction engineering research laboratories, as well as in oil and gas, petrochemical and petrochemical refining industries. Motivated by vast applications of SPECT technique, this work attempts to study the application of SPECT on a Pebble Bed Reactor (PBR) using numerical phantom of pebbles inside the PBR core. From the cross-sectional images obtained from SPECT, the behavior of pebbles inside the core can be analyzed for further improvement of the PBR design. As the quality of the reconstructed image is largely dependent on the algorithm used, this work aims to compare two image reconstruction algorithms for SPECT, namely the Expectation Maximization Algorithm and the Exact Inversion Formula. The results obtained from the Exact Inversion Formula showed better image contrast and sharpness, and shorter computational time compared to the Expectation Maximization Algorithm.

  10. Image reconstruction of single photon emission computed tomography (SPECT) on a pebble bed reactor (PBR) using expectation maximization and exact inversion algorithms: Comparison study by means of numerical phantom

    SciTech Connect

    Razali, Azhani Mohd Abdullah, Jaafar

    2015-04-29

    Single Photon Emission Computed Tomography (SPECT) is a well-known imaging technique used in medical application, and it is part of medical imaging modalities that made the diagnosis and treatment of disease possible. However, SPECT technique is not only limited to the medical sector. Many works are carried out to adapt the same concept by using high-energy photon emission to diagnose process malfunctions in critical industrial systems such as in chemical reaction engineering research laboratories, as well as in oil and gas, petrochemical and petrochemical refining industries. Motivated by vast applications of SPECT technique, this work attempts to study the application of SPECT on a Pebble Bed Reactor (PBR) using numerical phantom of pebbles inside the PBR core. From the cross-sectional images obtained from SPECT, the behavior of pebbles inside the core can be analyzed for further improvement of the PBR design. As the quality of the reconstructed image is largely dependent on the algorithm used, this work aims to compare two image reconstruction algorithms for SPECT, namely the Expectation Maximization Algorithm and the Exact Inversion Formula. The results obtained from the Exact Inversion Formula showed better image contrast and sharpness, and shorter computational time compared to the Expectation Maximization Algorithm.

  11. Resource Utilization by Children with Developmental Disabilities in Kenya: Discrepancy Analysis of Parents' Expectation-to-Importance Appraisals.

    ERIC Educational Resources Information Center

    Mutua, N. Kagendo; Miller, Janice Williams; Mwavita, Mwarumba

    2002-01-01

    A study investigated parental perceptions (n=351) of eight physical and human resources available to meet the needs of children with developmental disabilities in Kenya. Most parents reported a match between expected use and importance in five areas: health, friends, religious affiliation, community acceptance, and having one's own home. (Contains

  12. Expected utility of voluntary vaccination in the middle of an emergent Bluetongue virus serotype 8 epidemic: a decision analysis parameterized for Dutch circumstances.

    PubMed

    Sok, J; Hogeveen, H; Elbers, A R W; Velthuis, A G J; Oude Lansink, A G J M

    2014-08-01

    In order to put a halt to the Bluetongue virus serotype 8 (BTV-8) epidemic in 2008, the European Commission promoted vaccination at a transnational level as a new measure to combat BTV-8. Most European member states opted for a mandatory vaccination campaign, whereas the Netherlands, amongst others, opted for a voluntary campaign. For the latter to be effective, the farmer's willingness to vaccinate should be high enough to reach satisfactory vaccination coverage to stop the spread of the disease. This study looked at a farmer's expected utility of vaccination, which is expected to have a positive impact on the willingness to vaccinate. Decision analysis was used to structure the vaccination decision problem into decisions, events and payoffs, and to define the relationships among these elements. Two scenarios were formulated to distinguish farmers' mindsets, based on differences in dairy heifer management. For each of the scenarios, a decision tree was run for two years to study vaccination behaviour over time. The analysis was done based on the expected utility criterion. This allows to account for the effect of a farmer's risk preference on the vaccination decision. Probabilities were estimated by experts, payoffs were based on an earlier published study. According to the results of the simulation, the farmer decided initially to vaccinate against BTV-8 as the net expected utility of vaccination was positive. Re-vaccination was uncertain due to less expected costs of a continued outbreak. A risk averse farmer in this respect is more likely to re-vaccinate. When heifers were retained for export on the farm, the net expected utility of vaccination was found to be generally larger and thus was re-vaccination more likely to happen. For future animal health programmes that rely on a voluntary approach, results show that the provision of financial incentives can be adjusted to the farmers' willingness to vaccinate over time. Important in this respect are the decision moment and the characteristics of the disease. Farmers' perceptions of the disease risk and about the efficacy of available control options cannot be neglected. PMID:24768508

  13. Managing Expectations: Results from Case Studies of US Water Utilities on Preparing for, Coping with, and Adapting to Extreme Events

    NASA Astrophysics Data System (ADS)

    Beller-Simms, N.; Metchis, K.

    2014-12-01

    Water utilities, reeling from increased impacts of successive extreme events such as floods, droughts, and derechos, are taking a more proactive role in preparing for future incursions. A recent study by Federal and water foundation investigators, reveals how six US water utilities and their regions prepared for, responded to, and coped with recent extreme weather and climate events and the lessons they are using to plan future adaptation and resilience activities. Two case studies will be highlighted. (1) Sonoma County, CA, has had alternating floods and severe droughts. In 2009, this area, home to competing water users, namely, agricultural crops, wineries, tourism, and fisheries faced a three-year drought, accompanied at the end by intense frosts. Competing uses of water threatened the grape harvest, endangered the fish industry and resulted in a series of regulations, and court cases. Five years later, new efforts by partners in the entire watershed have identified mutual opportunities for increased basin sustainability in the face of a changing climate. (2) Washington DC had a derecho in late June 2012, which curtailed water, communications, and power delivery during a record heat spell that impacted hundreds of thousands of residents and lasted over the height of the tourist-intensive July 4th holiday. Lessons from this event were applied three months later in anticipation of an approaching Superstorm Sandy. This study will help other communities in improving their resiliency in the face of future climate extremes. For example, this study revealed that (1) communities are planning with multiple types and occurrences of extreme events which are becoming more severe and frequent and are impacting communities that are expanding into more vulnerable areas and (2) decisions by one sector can not be made in a vacuum and require the scientific, sectoral and citizen communities to work towards sustainable solutions.

  14. Prognostic utility of predischarge dipyridamole-thallium imaging compared to predischarge submaximal exercise electrocardiography and maximal exercise thallium imaging after uncomplicated acute myocardial infarction

    SciTech Connect

    Gimple, L.W.; Hutter, A.M. Jr.; Guiney, T.E.; Boucher, C.A. )

    1989-12-01

    The prognostic value of predischarge dipyridamole-thallium scanning after uncomplicated myocardial infarction was determined by comparison with submaximal exercise electrocardiography and 6-week maximal exercise thallium imaging and by correlation with clinical events. Two endpoints were defined: cardiac events and severe ischemic potential. Of the 40 patients studied, 8 had cardiac events within 6 months (1 died, 3 had myocardial infarction and 4 had unstable angina requiring hospitalization). The finding of any redistribution on dipyridamole-thallium scanning was common (77%) in these patients and had poor specificity (29%). Redistribution outside of the infarct zone, however, had equivalent sensitivity (63%) and better specificity (75%) for events (p less than 0.05). Both predischarge dipyridamole-thallium and submaximal exercise electrocardiography identified 5 of the 8 events (p = 0.04 and 0.07, respectively). The negative predictive accuracy for events for both dipyridamole-thallium and submaximal exercise electrocardiography was 88%. In addition to the 8 patients with events, 16 other patients had severe ischemic potential (6 had coronary bypass surgery, 1 had inoperable 3-vessel disease and 9 had markedly abnormal 6-week maximal exercise tests). Predischarge dipyridamole-thallium and submaximal exercise testing also identified 8 and 7 of these 16 patients with severe ischemic potential, respectively. Six of the 8 cardiac events occurred before 6-week follow-up. A maximal exercise thallium test at 6 weeks identified 1 of the 2 additional events within 6 months correctly. Thallium redistribution after dipyridamole in coronary territories outside the infarct zone is a sensitive and specific predictor of subsequent cardiac events and identifies patients with severe ischemic potential.

  15. Evidence for surprise minimization over value maximization in choice behavior.

    PubMed

    Schwartenbeck, Philipp; FitzGerald, Thomas H B; Mathys, Christoph; Dolan, Ray; Kronbichler, Martin; Friston, Karl

    2015-01-01

    Classical economic models are predicated on the idea that the ultimate aim of choice is to maximize utility or reward. In contrast, an alternative perspective highlights the fact that adaptive behavior requires agents' to model their environment and minimize surprise about the states they frequent. We propose that choice behavior can be more accurately accounted for by surprise minimization compared to reward or utility maximization alone. Minimizing surprise makes a prediction at variance with expected utility models; namely, that in addition to attaining valuable states, agents attempt to maximize the entropy over outcomes and thus 'keep their options open'. We tested this prediction using a simple binary choice paradigm and show that human decision-making is better explained by surprise minimization compared to utility maximization. Furthermore, we replicated this entropy-seeking behavior in a control task with no explicit utilities. These findings highlight a limitation of purely economic motivations in explaining choice behavior and instead emphasize the importance of belief-based motivations. PMID:26564686

  16. Evidence for surprise minimization over value maximization in choice behavior

    PubMed Central

    Schwartenbeck, Philipp; FitzGerald, Thomas H. B.; Mathys, Christoph; Dolan, Ray; Kronbichler, Martin; Friston, Karl

    2015-01-01

    Classical economic models are predicated on the idea that the ultimate aim of choice is to maximize utility or reward. In contrast, an alternative perspective highlights the fact that adaptive behavior requires agents to model their environment and minimize surprise about the states they frequent. We propose that choice behavior can be more accurately accounted for by surprise minimization compared to reward or utility maximization alone. Minimizing surprise makes a prediction at variance with expected utility models; namely, that in addition to attaining valuable states, agents attempt to maximize the entropy over outcomes and thus keep their options open. We tested this prediction using a simple binary choice paradigm and show that human decision-making is better explained by surprise minimization compared to utility maximization. Furthermore, we replicated this entropy-seeking behavior in a control task with no explicit utilities. These findings highlight a limitation of purely economic motivations in explaining choice behavior and instead emphasize the importance of belief-based motivations. PMID:26564686

  17. GUIDELINES FOR NOX CONTROL BY COMBUSTION MODIFICATION FOR COAL-FIRED UTILITY BOILERS. PROCEDURES FOR REDUCTION OF NOX EMISSIONS AND MAXIMIZATION OF BOILER EFFICIENCY

    EPA Science Inventory

    The report, which has been reviewed by industry experts, reflects the experience developed in successfully applying combustion modifications to reduce NOx emissions from coal-fired utility boilers. Although the report emphasizes coal-fired equipment, the same principles can be ap...

  18. On deciding to have a lobotomy: either lobotomies were justified or decisions under risk should not always seek to maximise expected utility.

    PubMed

    Cooper, Rachel

    2014-02-01

    In the 1940s and 1950s thousands of lobotomies were performed on people with mental disorders. These operations were known to be dangerous, but thought to offer great hope. Nowadays, the lobotomies of the 1940s and 1950s are widely condemned. The consensus is that the practitioners who employed them were, at best, misguided enthusiasts, or, at worst, evil. In this paper I employ standard decision theory to understand and assess shifts in the evaluation of lobotomy. Textbooks of medical decision making generally recommend that decisions under risk are made so as to maximise expected utility (MEU) I show that using this procedure suggests that the 1940s and 1950s practice of psychosurgery was justifiable. In making sense of this finding we have a choice: Either we can accept that psychosurgery was justified, in which case condemnation of the lobotomists is misplaced. Or, we can conclude that the use of formal decision procedures, such as MEU, is problematic. PMID:24449251

  19. Aging and loss decision making: increased risk aversion and decreased use of maximizing information, with correlated rationality and value maximization.

    PubMed

    Kurnianingsih, Yoanna A; Sim, Sam K Y; Chee, Michael W L; Mullette-Gillman, O'Dhaniel A

    2015-01-01

    We investigated how adult aging specifically alters economic decision-making, focusing on examining alterations in uncertainty preferences (willingness to gamble) and choice strategies (what gamble information influences choices) within both the gains and losses domains. Within each domain, participants chose between certain monetary outcomes and gambles with uncertain outcomes. We examined preferences by quantifying how uncertainty modulates choice behavior as if altering the subjective valuation of gambles. We explored age-related preferences for two types of uncertainty, risk, and ambiguity. Additionally, we explored how aging may alter what information participants utilize to make their choices by comparing the relative utilization of maximizing and satisficing information types through a choice strategy metric. Maximizing information was the ratio of the expected value of the two options, while satisficing information was the probability of winning. We found age-related alterations of economic preferences within the losses domain, but no alterations within the gains domain. Older adults (OA; 61-80 years old) were significantly more uncertainty averse for both risky and ambiguous choices. OA also exhibited choice strategies with decreased use of maximizing information. Within OA, we found a significant correlation between risk preferences and choice strategy. This linkage between preferences and strategy appears to derive from a convergence to risk neutrality driven by greater use of the effortful maximizing strategy. As utility maximization and value maximization intersect at risk neutrality, this result suggests that OA are exhibiting a relationship between enhanced rationality and enhanced value maximization. While there was variability in economic decision-making measures within OA, these individual differences were unrelated to variability within examined measures of cognitive ability. Our results demonstrate that aging alters economic decision-making for losses through changes in both individual preferences and the strategies individuals employ. PMID:26029092

  20. Aging and loss decision making: increased risk aversion and decreased use of maximizing information, with correlated rationality and value maximization

    PubMed Central

    Kurnianingsih, Yoanna A.; Sim, Sam K. Y.; Chee, Michael W. L.; Mullette-Gillman, ODhaniel A.

    2015-01-01

    We investigated how adult aging specifically alters economic decision-making, focusing on examining alterations in uncertainty preferences (willingness to gamble) and choice strategies (what gamble information influences choices) within both the gains and losses domains. Within each domain, participants chose between certain monetary outcomes and gambles with uncertain outcomes. We examined preferences by quantifying how uncertainty modulates choice behavior as if altering the subjective valuation of gambles. We explored age-related preferences for two types of uncertainty, risk, and ambiguity. Additionally, we explored how aging may alter what information participants utilize to make their choices by comparing the relative utilization of maximizing and satisficing information types through a choice strategy metric. Maximizing information was the ratio of the expected value of the two options, while satisficing information was the probability of winning. We found age-related alterations of economic preferences within the losses domain, but no alterations within the gains domain. Older adults (OA; 6180 years old) were significantly more uncertainty averse for both risky and ambiguous choices. OA also exhibited choice strategies with decreased use of maximizing information. Within OA, we found a significant correlation between risk preferences and choice strategy. This linkage between preferences and strategy appears to derive from a convergence to risk neutrality driven by greater use of the effortful maximizing strategy. As utility maximization and value maximization intersect at risk neutrality, this result suggests that OA are exhibiting a relationship between enhanced rationality and enhanced value maximization. While there was variability in economic decision-making measures within OA, these individual differences were unrelated to variability within examined measures of cognitive ability. Our results demonstrate that aging alters economic decision-making for losses through changes in both individual preferences and the strategies individuals employ. PMID:26029092

  1. DEVELOPMENT OF A VALIDATED MODEL FOR USE IN MINIMIZING NOx EMISSIONS AND MAXIMIZING CARBON UTILIZATION WHEN CO-FIRING BIOMASS WITH COAL

    SciTech Connect

    Larry G. Felix; P. Vann Bush

    2003-01-29

    This is the ninth Quarterly Technical Report for DOE Cooperative Agreement No. DE-FC26-00NT40895. A statement of the project objectives is included in the Introduction of this report. The pilot-scale testing phase of the project has been completed. Calculations are essentially completed for implementing a modeling approach to combine reaction times and temperature distributions from computational fluid dynamic models of the pilot-scale combustion furnace with char burnout and chemical reaction kinetics to predict NO{sub x} emissions and unburned carbon levels in the furnace exhaust. The REI Configurable Fireside Simulator (CFS) has proven to be an essential component to provide input for these calculations. Niksa Energy Associates expects to deliver their final report in February 2003. Work has continued on the project final report.

  2. Maximizing the utilization of Laminaria japonica as biomass via improvement of alginate lyase activity in a two-phase fermentation system.

    PubMed

    Oh, Yuri; Xu, Xu; Kim, Ji Young; Park, Jong Moon

    2015-08-01

    Brown seaweed contains up to 67% of carbohydrates by dry weight and presents high potential as a polysaccharide feedstock for biofuel production. To effectively use brown seaweed as a biomass, degradation of alginate is the major challenge due to its complicated structure and low solubility in water. This study focuses on the isolation of alginate degrading bacteria, determining of the optimum fermentation conditions, as well as comparing the conventional single fermentation system with the two-phase fermentation system which is separately using alginate and mannitol extracted from Laminaria japonica. Maximum yield of organic acids production and volatile solids reduction obtained were 0.516 g/g and 79.7%, respectively, using the two-phase fermentation system in which alginate fermentation was carried out at pH 7 and mannitol fermentation at pH 8. The two-phase fermentation system increased the yield of organic acids production by 1.14 times and led to a 1.45-times reduction of VS when compared to the conventional single fermentation system at pH 8. The results show that the two-phase fermentation system improved the utilization of alginate by separating alginate from mannitol leading to enhanced alginate lyase activity. PMID:26098412

  3. DEVELOPMENT OF A VALIDATED MODEL FOR USE IN MINIMIZING NOx EMISSIONS AND MAXIMIZING CARBON UTILIZATION WHEN CO-FIRING BIOMASS WITH COAL

    SciTech Connect

    Larry G. Felix; P. Vann Bush; Stephen Niksa

    2003-04-30

    In full-scale boilers, the effect of biomass cofiring on NO{sub x} and unburned carbon (UBC) emissions has been found to be site-specific. Few sets of field data are comparable and no consistent database of information exists upon which cofiring fuel choice or injection system design can be based to assure that NOX emissions will be minimized and UBC be reduced. This report presents the results of a comprehensive project that generated an extensive set of pilot-scale test data that were used to validate a new predictive model for the cofiring of biomass and coal. All testing was performed at the 3.6 MMBtu/hr (1.75 MW{sub t}) Southern Company Services/Southern Research Institute Combustion Research Facility where a variety of burner configurations, coals, biomasses, and biomass injection schemes were utilized to generate a database of consistent, scalable, experimental results (422 separate test conditions). This database was then used to validate a new model for predicting NO{sub x} and UBC emissions from the cofiring of biomass and coal. This model is based on an Advanced Post-Processing (APP) technique that generates an equivalent network of idealized reactor elements from a conventional CFD simulation. The APP reactor network is a computational environment that allows for the incorporation of all relevant chemical reaction mechanisms and provides a new tool to quantify NOx and UBC emissions for any cofired combination of coal and biomass.

  4. Maximally natural supersymmetry.

    PubMed

    Dimopoulos, Savas; Howe, Kiel; March-Russell, John

    2014-09-12

    We consider 4D weak scale theories arising from 5D supersymmetric (SUSY) theories with maximal Scherk-Schwarz breaking at a Kaluza-Klein scale of several TeV. Many of the problems of conventional SUSY are avoided. Apart from 3rd family sfermions the SUSY spectrum is heavy, with only ∼50% tuning at a gluino mass of ∼2  TeV and a stop mass of ∼650  GeV. A single Higgs doublet acquires a vacuum expectation value, so the physical Higgs boson is automatically standard-model-like. A new U(1)^{'} interaction raises m_{h} to 126 GeV. For minimal tuning the associated Z^{'}, as well as the 3rd family sfermions, must be accessible to LHC13. A gravitational wave signal consistent with hints from BICEP2 is possible if inflation occurs when the extra dimensions are small. PMID:25259967

  5. DEVELOPMENT OF A VALIDATED MODEL FOR USE IN MINIMIZING NOx EMISSIONS AND MAXIMIZING CARBON UTILIZATION WHEN CO-FIRING BIOMASS WITH COAL

    SciTech Connect

    Larry G. Felix; P. Vann Bush

    2002-04-30

    This is the sixth Quarterly Technical Report for DOE Cooperative Agreement No. DE-FC26-00NT40895. A statement of the project objectives is included in the Introduction of this report. Two additional biomass co-firing test burns were conducted during this quarter. In the first test (Test 10), up to 20% by weight dry hardwood sawdust and switchgrass was compiled with Galatia coal and injected through the dual-register burner. Galatia coal is a medium-sulfur Illinois Basin coal ({approx}1.0% S). The dual-register burner is a generic low-NO{sub x} burner that incorporates two independent wind boxes. In the second test (Test 11), regular ({approx}70% passing 200 mesh) and finely ground ({approx}90% passing 200 mesh) Pratt Seam coal was injected through the single-register burner to determine if coal grind affects NO{sub x} and unburned carbon emissions. The results of these tests are presented in this quarterly report. Significant progress has been made in implementing a modeling approach to combine reaction times and temperature distributions from computational fluid dynamic models of the pilot-scale combustion furnace with char burnout and chemical reaction kinetics to predict NO{sub x} emissions and unburned carbon levels in the furnace exhaust. No additional results of CFD modeling have been received as delivery of the Configurable Fireside Simulator is expected during the next quarter. Preparations are under way for continued pilot-scale combustion experiments with the single-register burner and a low-volatility bituminous coal. Some delays have been experienced in the acquisition and processing of biomass. Finally, a project review was held at the offices of Southern Research in Birmingham, on February 27, 2002.

  6. Maximally Expressive Modeling

    NASA Technical Reports Server (NTRS)

    Jaap, John; Davis, Elizabeth; Richardson, Lea

    2004-01-01

    Planning and scheduling systems organize tasks into a timeline or schedule. Tasks are logically grouped into containers called models. Models are a collection of related tasks, along with their dependencies and requirements, that when met will produce the desired result. One challenging domain for a planning and scheduling system is the operation of on-board experiments for the International Space Station. In these experiments, the equipment used is among the most complex hardware ever developed; the information sought is at the cutting edge of scientific endeavor; and the procedures are intricate and exacting. Scheduling is made more difficult by a scarcity of station resources. The models to be fed into the scheduler must describe both the complexity of the experiments and procedures (to ensure a valid schedule) and the flexibilities of the procedures and the equipment (to effectively utilize available resources). Clearly, scheduling International Space Station experiment operations calls for a maximally expressive modeling schema.

  7. A Column Generation Approach to Solve Multi-Team Influence Maximization Problem for Social Lottery Design

    NASA Astrophysics Data System (ADS)

    Jois, Manjunath Holaykoppa Nanjunda

    The conventional Influence Maximization problem is the problem of finding such a team (a small subset) of seed nodes in a social network that would maximize the spread of influence over the whole network. This paper considers a lottery system aimed at maximizing the awareness spread to promote energy conservation behavior as a stochastic Influence Maximization problem with the constraints ensuring lottery fairness. The resulting Multi-Team Influence Maximization problem involves assigning the probabilities to multiple teams of seeds (interpreted as lottery winners) to maximize the expected awareness spread. Such a variation of the Influence Maximization problem is modeled as a Linear Program; however, enumerating all the possible teams is a hard task considering that the feasible team count grows exponentially with the network size. In order to address this challenge, we develop a column generation based approach to solve the problem with a limited number of candidate teams, where new candidates are generated and added to the problem iteratively. We adopt a piecewise linear function to model the impact of including a new team so as to pick only such teams which can improve the existing solution. We demonstrate that with this approach we can solve such influence maximization problems to optimality, and perform computational study with real-world social network data sets to showcase the efficiency of the approach in finding lottery designs for optimal awareness spread. Lastly, we explore other possible scenarios where this model can be utilized to optimally solve the otherwise hard to solve influence maximization problems.

  8. Maximally Expressive Task Modeling

    NASA Technical Reports Server (NTRS)

    Japp, John; Davis, Elizabeth; Maxwell, Theresa G. (Technical Monitor)

    2002-01-01

    Planning and scheduling systems organize "tasks" into a timeline or schedule. The tasks are defined within the scheduling system in logical containers called models. The dictionary might define a model of this type as "a system of things and relations satisfying a set of rules that, when applied to the things and relations, produce certainty about the tasks that are being modeled." One challenging domain for a planning and scheduling system is the operation of on-board experiment activities for the Space Station. The equipment used in these experiments is some of the most complex hardware ever developed by mankind, the information sought by these experiments is at the cutting edge of scientific endeavor, and the procedures for executing the experiments are intricate and exacting. Scheduling is made more difficult by a scarcity of space station resources. The models to be fed into the scheduler must describe both the complexity of the experiments and procedures (to ensure a valid schedule) and the flexibilities of the procedures and the equipment (to effectively utilize available resources). Clearly, scheduling space station experiment operations calls for a "maximally expressive" modeling schema. Modeling even the simplest of activities cannot be automated; no sensor can be attached to a piece of equipment that can discern how to use that piece of equipment; no camera can quantify how to operate a piece of equipment. Modeling is a human enterprise-both an art and a science. The modeling schema should allow the models to flow from the keyboard of the user as easily as works of literature flowed from the pen of Shakespeare. The Ground Systems Department at the Marshall Space Flight Center has embarked on an effort to develop a new scheduling engine that is highlighted by a maximally expressive modeling schema. This schema, presented in this paper, is a synergy of technological advances and domain-specific innovations.

  9. Exceeding Expectations

    ERIC Educational Resources Information Center

    Cannon, John

    2011-01-01

    Awareness of expectations is so important in the facilities business. The author's experiences has taught him that it is essential to understand how expectations impact people's lives as well as those for whom they provide services for every day. This article presents examples and ideas that will provide insight and ideas to help educators…

  10. Maximization, learning, and economic behavior.

    PubMed

    Erev, Ido; Roth, Alvin E

    2014-07-22

    The rationality assumption that underlies mainstream economic theory has proved to be a useful approximation, despite the fact that systematic violations to its predictions can be found. That is, the assumption of rational behavior is useful in understanding the ways in which many successful economic institutions function, although it is also true that actual human behavior falls systematically short of perfect rationality. We consider a possible explanation of this apparent inconsistency, suggesting that mechanisms that rest on the rationality assumption are likely to be successful when they create an environment in which the behavior they try to facilitate leads to the best payoff for all agents on average, and most of the time. Review of basic learning research suggests that, under these conditions, people quickly learn to maximize expected return. This review also shows that there are many situations in which experience does not increase maximization. In many cases, experience leads people to underweight rare events. In addition, the current paper suggests that it is convenient to distinguish between two behavioral approaches to improve economic analyses. The first, and more conventional approach among behavioral economists and psychologists interested in judgment and decision making, highlights violations of the rational model and proposes descriptive models that capture these violations. The second approach studies human learning to clarify the conditions under which people quickly learn to maximize expected return. The current review highlights one set of conditions of this type and shows how the understanding of these conditions can facilitate market design. PMID:25024182

  11. Maximization, learning, and economic behavior

    PubMed Central

    Erev, Ido; Roth, Alvin E.

    2014-01-01

    The rationality assumption that underlies mainstream economic theory has proved to be a useful approximation, despite the fact that systematic violations to its predictions can be found. That is, the assumption of rational behavior is useful in understanding the ways in which many successful economic institutions function, although it is also true that actual human behavior falls systematically short of perfect rationality. We consider a possible explanation of this apparent inconsistency, suggesting that mechanisms that rest on the rationality assumption are likely to be successful when they create an environment in which the behavior they try to facilitate leads to the best payoff for all agents on average, and most of the time. Review of basic learning research suggests that, under these conditions, people quickly learn to maximize expected return. This review also shows that there are many situations in which experience does not increase maximization. In many cases, experience leads people to underweight rare events. In addition, the current paper suggests that it is convenient to distinguish between two behavioral approaches to improve economic analyses. The first, and more conventional approach among behavioral economists and psychologists interested in judgment and decision making, highlights violations of the rational model and proposes descriptive models that capture these violations. The second approach studies human learning to clarify the conditions under which people quickly learn to maximize expected return. The current review highlights one set of conditions of this type and shows how the understanding of these conditions can facilitate market design. PMID:25024182

  12. Great Expectations.

    ERIC Educational Resources Information Center

    Natale, Jo Anna

    1993-01-01

    Inside one Washington, DC, elementary school, Principal John Pannell has high hopes for his students and an expansive school vision. Malcolm X School compensates for disorder outside by clearly inculcating rules and behavior expectations. Children in school uniforms daily repeat a motto promoting Malcolm X as a school of love allowing no hitting,…

  13. Inclusive fitness maximization: An axiomatic approach.

    PubMed

    Okasha, Samir; Weymark, John A; Bossert, Walter

    2014-06-01

    Kin selection theorists argue that evolution in social contexts will lead organisms to behave as if maximizing their inclusive, as opposed to personal, fitness. The inclusive fitness concept allows biologists to treat organisms as akin to rational agents seeking to maximize a utility function. Here we develop this idea and place it on a firm footing by employing a standard decision-theoretic methodology. We show how the principle of inclusive fitness maximization and a related principle of quasi-inclusive fitness maximization can be derived from axioms on an individual׳s 'as if preferences' (binary choices) for the case in which phenotypic effects are additive. Our results help integrate evolutionary theory and rational choice theory, help draw out the behavioural implications of inclusive fitness maximization, and point to a possible way in which evolution could lead organisms to implement it. PMID:24530825

  14. Generation and Transmission Maximization Model

    Energy Science and Technology Software Center (ESTSC)

    2001-04-05

    GTMax was developed to study complex marketing and system operational issues facing electric utility power systems. The model maximizes the value of the electric system taking into account not only a single system''s limited energy and transmission resources but also firm contracts, independent power producer (IPP) agreements, and bulk power transaction opportunities on the spot market. GTMax maximizes net revenues of power systems by finding a solution that increases income while keeping expenses at amore » minimum. It does this while ensuring that market transactions and system operations are within the physical and institutional limitations of the power system. When multiple systems are simulated, GTMax identifies utilities that can successfully compete on the market by tracking hourly energy transactions, costs, and revenues. Some limitations that are modeled are power plant seasonal capabilities and terms specified in firm and IPP contracts. GTMax also considers detaile operational limitations such as power plant ramp rates and hydropower reservoir constraints.« less

  15. Maximal Outboxes of Quadrilaterals

    ERIC Educational Resources Information Center

    Zhao, Dongsheng

    2011-01-01

    An outbox of a quadrilateral is a rectangle such that each vertex of the given quadrilateral lies on one side of the rectangle and different vertices lie on different sides. We first investigate those quadrilaterals whose every outbox is a square. Next, we consider the maximal outboxes of rectangles and those quadrilaterals with perpendicular

  16. Infrared Maximally Abelian Gauge

    SciTech Connect

    Mendes, Tereza; Cucchieri, Attilio; Mihara, Antonio

    2007-02-27

    The confinement scenario in Maximally Abelian gauge (MAG) is based on the concepts of Abelian dominance and of dual superconductivity. Recently, several groups pointed out the possible existence in MAG of ghost and gluon condensates with mass dimension 2, which in turn should influence the infrared behavior of ghost and gluon propagators. We present preliminary results for the first lattice numerical study of the ghost propagator and of ghost condensation for pure SU(2) theory in the MAG.

  17. Quantum-Inspired Maximizer

    NASA Technical Reports Server (NTRS)

    Zak, Michail

    2008-01-01

    A report discusses an algorithm for a new kind of dynamics based on a quantum- classical hybrid-quantum-inspired maximizer. The model is represented by a modified Madelung equation in which the quantum potential is replaced by different, specially chosen 'computational' potential. As a result, the dynamics attains both quantum and classical properties: it preserves superposition and entanglement of random solutions, while allowing one to measure its state variables, using classical methods. Such optimal combination of characteristics is a perfect match for quantum-inspired computing. As an application, an algorithm for global maximum of an arbitrary integrable function is proposed. The idea of the proposed algorithm is very simple: based upon the Quantum-inspired Maximizer (QIM), introduce a positive function to be maximized as the probability density to which the solution is attracted. Then the larger value of this function will have the higher probability to appear. Special attention is paid to simulation of integer programming and NP-complete problems. It is demonstrated that the problem of global maximum of an integrable function can be found in polynomial time by using the proposed quantum- classical hybrid. The result is extended to a constrained maximum with applications to integer programming and TSP (Traveling Salesman Problem).

  18. Maximized thermal efficiency engines

    NASA Astrophysics Data System (ADS)

    Pinto, A. P.

    This paper discusses what happens to the working gas in a state-of-the-art Stirling engine as the working gas is transferred between the hot and cold cylinders. The working gas that crosses over from the hot cylinder to the cold cylinder during the expansion process ceases to contribute power to the crank shaft the instant it crosses over, and contributes negatively to the overall efficiency. In a similar manner, the working gas that is present in the hot cylinder during the compression process also decrease the overall efficiency. The requirements for a maximized thermal efficiency engine are listed. Three mechanical embodiments wherein these requirements are met and where Carnot efficiency is achievable are described.

  19. Maximizing relationship possibilities: relational maximization in romantic relationships.

    PubMed

    Mikkelson, Alan C; Pauley, Perry M

    2013-01-01

    Using Rusbult's (1980) investment model and Schwartz's (2000) conceptualization of decision maximization, we sought to understand how an individual's propensity to maximize his or her decisions factored into investment, satisfaction, and awareness of alternatives in romantic relationships. In study one, 275 participants currently involved in romantic relationships completed measures of maximization, satisfaction, investment size, quality of alternatives, and commitment. In study two, 343 participants were surveyed as part of the creation of a scale of relational maximization. Results from both studies revealed that the tendency to maximize (in general and in relationships specifically) was negatively correlated with satisfaction, investment, and commitment, and positively correlated with quality of alternatives. Furthermore, we found that satisfaction and investments mediated the relationship between maximization and relationship commitment. PMID:23951952

  20. Smoking Outcome Expectancies among College Students.

    ERIC Educational Resources Information Center

    Brandon, Thomas H.; Baker, Timothy B.

    Alcohol expectancies have been found to predict later onset of drinking among adolescents. This study examined whether the relationship between level of alcohol use and expectancies is paralleled with cigarette smoking, and attempted to identify the content of smoking expectancies. An instrument to measure the subjective expected utility of

  1. Maximizing Brightness in Photoinjectors

    SciTech Connect

    Limborg-Deprey, C.; Tomizawa, H.; /JAERI-RIKEN, Hyogo

    2011-11-30

    If the laser pulse driving photoinjectors could be arbitrarily shaped, the emittance growth induced by space charge effects could be totally compensated for. In particular, for RF guns the photo-electron distribution leaving the cathode should have a 3D-ellipsoidal shape. The emittance at the end of the injector could be as small as the cathode emittance. We explore how the emittance and the brightness can be optimized for photoinjector based on RF gun depending on the peak current requirements. Techniques available to produce those ideal laser pulse shapes are also discussed. If the laser pulse driving photoinjectors could be arbitrarily shaped, the emittance growth induced by space charge effects could be totally compensated for. In particular, for RF guns, the photo-electron distribution leaving the cathode should be close to a uniform distribution contained in a 3D-ellipsoid contour. For photo-cathodes which have very fast emission times, and assuming a perfectly uniform emitting surface, this could be achieved by shaping the laser in a pulse of constant fluence and limited in space by a 3D-ellipsoid contour. Simulations show that in such conditions, with the standard linear emittance compensation, the emittance at the end of the photo-injector beamline approaches the minimum value imposed by the cathode emittance. Brightness, which is expressed as the ratio of peak current over the product of the two transverse emittance, seems to be maximized for small charges. Numerical simulations also show that for very high charge per bunch (10nC), emittances as small as 2 mm-mrad could be reached by using 3D-ellipsoidal laser pulses in an S-Band gun. The production of 3D-ellipsoidal pulses is very challenging, but seems worthwhile the effort. We briefly discuss some of the present ideas and difficulties of achieving such pulses.

  2. COPD: maximization of bronchodilation.

    PubMed

    Nardini, Stefano; Camiciottoli, Gianna; Locicero, Salvatore; Maselli, Rosario; Pasqua, Franco; Passalacqua, Giovanni; Pela, Riccardo; Pesci, Alberto; Sebastiani, Alfredo; Vatrella, Alessandro

    2014-01-01

    The most recent guidelines define COPD in a multidimensional way, nevertheless the diagnosis is still linked to the limitation of airflow, usually measured by the reduction in the FEV1/FVC ratio below 70%. However, the severity of obstruction is not directly correlated to symptoms or to invalidity determined by COPD. Thus, besides respiratory function, COPD should be evaluated based on symptoms, frequency and severity of exacerbations, patient's functional status and health related quality of life (HRQoL). Therapy is mainly aimed at increasing exercise tolerance and reducing dyspnea, with improvement of daily activities and HRQoL. This can be accomplished by a drug-induced reduction of pulmonary hyperinflation and exacerbations frequency and severity. All guidelines recommend bronchodilators as baseline therapy for all stages of COPD, and long-acting inhaled bronchodilators, both beta-2 agonist (LABA) and antimuscarinic (LAMA) drugs, are the most effective in regular treatment in the clinically stable phase. The effectiveness of bronchodilators should be evaluated in terms of functional (relief of bronchial obstruction and pulmonary hyperinflation), symptomatic (exercise tolerance and HRQoL), and clinical improvement (reduction in number or severity of exacerbations), while the absence of a spirometric response is not a reason for interrupting treatment, if there is subjective improvement in symptoms. Because LABA and LAMA act via different mechanisms of action, when administered in combination they can exert additional effects, thus optimizing (i.e. maximizing) sustained bronchodilation in COPD patients with severe airflow limitation, who cannot benefit (or can get only partial benefit) by therapy with a single bronchodilator. Recently, a fixed combination of ultra LABA/LAMA (indacaterol/glycopyrronium) has shown that it is possible to get a stable and persistent bronchodilation, which can help in avoiding undesirable fluctuations of bronchial calibre. PMID:25364503

  3. Measure of nonlocality which is maximal for maximally entangled qutrits

    NASA Astrophysics Data System (ADS)

    Fonseca, E. A.; Parisio, Fernando

    2015-09-01

    There is no doubt about the fact that entanglement and nonlocality are distinct resources. It is acknowledged that a clear illustration of this point is the difference between maximally entangled states and states that maximally violate a Bell inequality. We give strong evidence that this anomaly may be an artifact of the measures that have been used to quantify nonlocality. By reasoning that the numeric value of a Bell function is akin to a witness rather than a quantifier, we define a measure of nonlocality and show that, for pairs of qutrits and of four-level systems, maximal entanglement does correspond to maximal nonlocality in the same scenario that gave rise to the discrepancy.

  4. Maximize x(a - x)

    ERIC Educational Resources Information Center

    Lange, L. H.

    1974-01-01

    Five different methods for determining the maximizing condition for x(a - x) are presented. Included is the ancient Greek version and a method attributed to Fermat. None of the proofs use calculus. (LS)

  5. Power Converters Maximize Outputs Of Solar Cell Strings

    NASA Technical Reports Server (NTRS)

    Frederick, Martin E.; Jermakian, Joel B.

    1993-01-01

    Microprocessor-controlled dc-to-dc power converters devised to maximize power transferred from solar photovoltaic strings to storage batteries and other electrical loads. Converters help in utilizing large solar photovoltaic arrays most effectively with respect to cost, size, and weight. Main points of invention are: single controller used to control and optimize any number of "dumb" tracker units and strings independently; power maximized out of converters; and controller in system is microprocessor.

  6. BIOMASS UTILIZATION

    EPA Science Inventory

    The biomass utilization task consists of the evaluation of a biomass conversion technology including research and development initiatives. The project is expected to provide information on co-control of pollutants, as well as, to prove the feasibility of biomass conversion techn...

  7. Maximizing TDRS Command Load Lifetime

    NASA Technical Reports Server (NTRS)

    Brown, Aaron J.

    2002-01-01

    The GNC software onboard ISS utilizes TORS command loads, and a simplistic model of TORS orbital motion to generate onboard TORS state vectors. Each TORS command load contains five "invariant" orbital elements which serve as inputs to the onboard propagation algorithm. These elements include semi-major axis, inclination, time of last ascending node crossing, right ascension of ascending node, and mean motion. Running parallel to the onboard software is the TORS Command Builder Tool application, located in the JSC Mission Control Center. The TORS Command Builder Tool is responsible for building the TORS command loads using a ground TORS state vector, mirroring the onboard propagation algorithm, and assessing the fidelity of current TORS command loads onboard ISS. The tool works by extracting a ground state vector at a given time from a current TORS ephemeris, and then calculating the corresponding "onboard" TORS state vector at the same time using the current onboard TORS command load. The tool then performs a comparison between these two vectors and displays the relative differences in the command builder tool GUI. If the RSS position difference between these two vectors exceeds the tolerable lim its, a new command load is built using the ground state vector and uplinked to ISS. A command load's lifetime is therefore defined as the time from when a command load is built to the time the RSS position difference exceeds the tolerable limit. From the outset of TORS command load operations (STS-98), command load lifetime was limited to approximately one week due to the simplicity of both the onboard propagation algorithm, and the algorithm used by the command builder tool to generate the invariant orbital elements. It was soon desired to extend command load lifetime in order to minimize potential risk due to frequent ISS commanding. Initial studies indicated that command load lifetime was most sensitive to changes in mean motion. Finding a suitable value for mean motion was therefore the key to achieving this goal. This goal was eventually realized through development of an Excel spreadsheet tool called EMMIE (Excel Mean Motion Interactive Estimation). EMMIE utilizes ground ephemeris nodal data to perform a least-squares fit to inferred mean anomaly as a function of time, thus generating an initial estimate for mean motion. This mean motion in turn drives a plot of estimated downtrack position difference versus time. The user can then manually iterate the mean motion, and determine an optimal value that will maximize command load lifetime. Once this optimal value is determined, the mean motion initially calculated by the command builder tool is overwritten with the new optimal value, and the command load is built for uplink to ISS. EMMIE also provides the capability for command load lifetime to be tracked through multiple TORS ephemeris updates. Using EMMIE, TORS command load lifetimes of approximately 30 days have been achieved.

  8. Expectation and conditioning

    NASA Astrophysics Data System (ADS)

    Coster, Adelle C. F.; Alstrm, Preben

    2001-02-01

    We present a dynamical model that embodies both classical and instrumental conditioning paradigms in the same framework. The model is based on the formation of expectations of stimuli and of rewards. The expectations of stimuli are formed in a recurrent process called expectation learning in which one activity pattern evokes another. The expectation of rewards or punishments (motivation) is modelled using reinforcement learning.

  9. Utilizing Partnerships to Maximize Resources in College Counseling Services

    ERIC Educational Resources Information Center

    Stewart, Allison; Moffat, Meridith; Travers, Heather; Cummins, Douglas

    2015-01-01

    Research indicates an increasing number of college students are experiencing severe psychological problems that are impacting their academic performance. However, many colleges and universities operate with constrained budgets that limit their ability to provide adequate counseling services for their student population. Moreover, accessing…

  10. Utilizing Partnerships to Maximize Resources in College Counseling Services

    ERIC Educational Resources Information Center

    Stewart, Allison; Moffat, Meridith; Travers, Heather; Cummins, Douglas

    2015-01-01

    Research indicates an increasing number of college students are experiencing severe psychological problems that are impacting their academic performance. However, many colleges and universities operate with constrained budgets that limit their ability to provide adequate counseling services for their student population. Moreover, accessing

  11. Changing expectancies: cognitive mechanisms and context effects.

    PubMed

    Wiers, Reinout W; Wood, Mark D; Darkes, Jack; Corbin, William R; Jones, Barry T; Sher, Kenneth J

    2003-02-01

    This article presents the proceedings of a symposium at the 2002 RSA Meeting in San Francisco, organized by Reinout W. Wiers and Mark D. Wood. The symposium combined two topics of recent interest in studies of alcohol expectancies: cognitive mechanisms in expectancy challenge studies, and context-related changes of expectancies. With increasing recognition of the substantial role played by alcohol expectancies in drinking, investigators have begun to develop and evaluate expectancy challenge procedures as a potentially promising new prevention strategy. The two major issues addressed in the symposium were whether expectancy challenges result in changes in expectancies that mediate intervention (outcome relations), and the influence of simulated bar environments ("bar labs," in which challenges are usually done) on expectancies. The presentations were (1) An introduction, by Jack Darkes; (2) Investigating the utility of alcohol expectancy challenge with heavy drinking college students, by Mark D. Wood; (3) Effects of an expectancy challenge on implicit and explicit expectancies and drinking, by Reinout W. Wiers; (4) Effects of graphic feedback and simulated bar assessments on alcohol expectancies and consumption, by William R. Corbin; (5) Implicit alcohol associations and context, by Barry T Jones; and (6) A discussion by Kenneth J. Sher, who pointed out that it is important not only to study changes of expectancies in the paradigm of an expectancy challenge but also to consider the role of changing expectancies in natural development and in treatments not explicitly aimed at changing expectancies. PMID:12605068

  12. Hostility, Maximization, & the Public Trust.

    ERIC Educational Resources Information Center

    Winston, Gordon C.

    1992-01-01

    Ideas from current economic theory are applied to the nation's attitudes toward higher education. Ideas about asymmetric market information, trust markets, nonprofit firms, and maximization on campus are discussed. Public relations problems concerning accounting, deficits, and interest arbitrage are identified. The need for increased efficiency

  13. The effects of erythrocythemia on blood viscosity, maximal systemic oxygen transport capacity and maximal rates of oxygen consumption in an amphibian.

    PubMed

    Hillman, S S; Withers, P C; Hedrick, M S; Kimmel, P B

    1985-01-01

    Graded erythrocythemia was induced by isovolemic loading of packed red blood cells in the toad, Bufo marinus. Blood viscosity, hematocrit, hemoglobin concentration, maximal aortic blood flow rate and maximal rates of oxygen consumption were determined after each load. Blood viscosity was related to hematocrit in the expected exponential manner; ln eta = 0.43 + 0.035 Hct. Maximal blood flow rates in the dorsal aorta were inversely proportional to blood viscosity and fit predictions of the Poiseuille-Hagen flow formula. The effect of increased blood viscosity was to reduce aortic pulse volume, but not maximal heart rate. Maximal systemic oxygen transport capacity (aortic blood flow rate X hemoglobin concentration X O2 binding capacity of hemoglobin) was linearly correlated with the maximal rate of oxygen consumption. These date indicate that optimal hematocrit theory is applicable for maximal blood flow rates in vivo, and that systemic oxygen transport is the primary limitation to aerial VO2 max in amphibians. PMID:3939237

  14. Maximal quantum Fisher information for general su(2) parametrization processes

    NASA Astrophysics Data System (ADS)

    Jing, Xiao-Xing; Liu, Jing; Xiong, Heng-Na; Wang, Xiaoguang

    2015-07-01

    Quantum Fisher information is a key concept in the field of quantum metrology, which aims to enhance the accuracy of parameter estimation by using quantum resources. In this paper, utilizing a representation of quantum Fisher information for a general unitary parametrization process, we study unitary parametrization processes governed by su(2) dynamics. We obtain the analytical expression for the Hermitian operator of the parametrization and the maximal quantum Fisher information. We find that the maximal quantum Fisher information over the parameter space consists of two parts; one is quadratic in time and the other oscillates with time. We apply our result to the estimation of a magnetic field and obtained the maximal quantum Fisher information. We further discuss a driving field with a time-dependent Hamiltonian and find that the maximal quantum Fisher information of the driving frequency attains the optimum when it is in resonance with the atomic frequency.

  15. Expecting the Best

    ERIC Educational Resources Information Center

    DiPaula, John

    2010-01-01

    Educational expectations are psychological constructs that change over time and can be altered or influenced by various factors. The concept of educational expectations refers to how much schooling students realistically believe that they will complete. These expectations are eventually raised or lowered as students see others like themselves…

  16. Prescription stimulant expectancies in recreational and medical users: results from a preliminary expectancy questionnaire.

    PubMed

    Looby, Alison; Earleywine, Mitch

    2009-01-01

    Given the rise of prescription stimulant misuse, examination of effect expectancies could prove helpful. The Prescription Stimulant Expectancy Questionnaire (PSEQ) was designed to explore positive and negative prescription stimulant-related expectancies. In 2006, 157 participants nationwide completed an Internet survey of prescription stimulant use, attention-deficit/hyperactivity disorder symptoms, and expectancies. Multiple regressions demonstrate that positive, but not negative expectancies, predicted frequency of use. Recreational and medical users were classified by hierarchical cluster analysis. Recreational users reported fewer positive and negative expectancies than medical users. Implications and limitations are discussed. Future research is warranted on prescription stimulant expectancies and the utility of the PSEQ. PMID:19938932

  17. Using Debate to Maximize Learning Potential: A Case Study

    ERIC Educational Resources Information Center

    Firmin, Michael W.; Vaughn, Aaron; Dye, Amanda

    2007-01-01

    Following a review of the literature, an educational case study is provided for the benefit of faculty preparing college courses. In particular, we provide a transcribed debate utilized in a General Psychology course as a best practice example of how to craft a debate which maximizes student learning. The work is presented as a model for the

  18. Elliptic functions and maximal unitarity

    NASA Astrophysics Data System (ADS)

    Søgaard, Mads; Zhang, Yang

    2015-04-01

    Scattering amplitudes at loop level can be reduced to a basis of linearly independent Feynman integrals. The integral coefficients are extracted from generalized unitarity cuts which define algebraic varieties. The topology of an algebraic variety characterizes the difficulty of applying maximal cuts. In this work, we analyze a novel class of integrals of which the maximal cuts give rise to an algebraic variety with irrational irreducible components. As a phenomenologically relevant example, we examine the two-loop planar double-box contribution with internal massive lines. We derive unique projectors for all four master integrals in terms of multivariate residues along with Weierstrass' elliptic functions. We also show how to generate the leading-topology part of otherwise infeasible integration-by-parts identities analytically from exact meromorphic differential forms.

  19. Maximal sweating rate in humans.

    PubMed

    Torii, M

    1995-12-01

    We reviewed the literature concerning the maximal sweating rate (SRmax) during heat acclimatization, walking in desert heat and marathon running, and analyzed it from the viewpoint of sex, age, level of maximal oxygen uptake, and experimental conditions, i.e., ambient temperature, relative humidity, work intensity, work type, working duration, seasonal factors and the techniques of heat acclimatization. Exercise simulation, walking, running or bicycling, to induce the SRmax was conducted in a hot climatic chamber or in the desert. The SRmaxs due to marathon running were 1,000 to 1,200 g.h-1 in the cold season and 1,500 to 2,000 g.h-1 in the hot season. After several days of heat acclimatization, sweating capacity in the exercise simulation reached a maximum rate, over 2,000 g.h-1. There was a sexual difference in the SRmax, and the sweating capacity in the female was less than that in the male. Thus, the maximal sweating capacity in human was observed by prolonged moderate muscular exercise under thermal stress and internal and/or external heat loads. PMID:9282540

  20. The maximal exercise ECG in asymptomatic men

    PubMed Central

    Cumming, Gordon R.; Borysyk, Lawrence; Dufresne, Cecile

    1972-01-01

    Lead MC5 bipolar exercise ECG was obtained in 510 asymptomatic males, aged 40 to 65, utilizing the bicycle ergometer, with maximal stress in 71% of the subjects. Ischemic changes occurred in 61 subjects, the frequency increasing from 4% at age 40 to 45, to 20% at age 50 to 55, to 37% at age 61 to 65. Subjects having an ischemic type ECG change on exercise had more frequent minor resting ECG changes, more resting hypertension, and a greater incidence of high cholesterol values than subjects with a normal ECG response to exercise, but there was no difference in the incidence of obesity, low fitness, or high systolic blood pressure after exercise. Current evidence suggests that asymptomatic male subjects with an abnormal exercise ECG develop clinical coronary heart disease from 2.5 to over 30 times more frequently than those with a normal exercise ECG. PMID:5012228

  1. Learning to maximize reward rate: a model based on semi-Markov decision processes.

    PubMed

    Khodadadi, Arash; Fakhari, Pegah; Busemeyer, Jerome R

    2014-01-01

    WHEN ANIMALS HAVE TO MAKE A NUMBER OF DECISIONS DURING A LIMITED TIME INTERVAL, THEY FACE A FUNDAMENTAL PROBLEM: how much time they should spend on each decision in order to achieve the maximum possible total outcome. Deliberating more on one decision usually leads to more outcome but less time will remain for other decisions. In the framework of sequential sampling models, the question is how animals learn to set their decision threshold such that the total expected outcome achieved during a limited time is maximized. The aim of this paper is to provide a theoretical framework for answering this question. To this end, we consider an experimental design in which each trial can come from one of the several possible "conditions." A condition specifies the difficulty of the trial, the reward, the penalty and so on. We show that to maximize the expected reward during a limited time, the subject should set a separate value of decision threshold for each condition. We propose a model of learning the optimal value of decision thresholds based on the theory of semi-Markov decision processes (SMDP). In our model, the experimental environment is modeled as an SMDP with each "condition" being a "state" and the value of decision thresholds being the "actions" taken in those states. The problem of finding the optimal decision thresholds then is cast as the stochastic optimal control problem of taking actions in each state in the corresponding SMDP such that the average reward rate is maximized. Our model utilizes a biologically plausible learning algorithm to solve this problem. The simulation results show that at the beginning of learning the model choses high values of decision threshold which lead to sub-optimal performance. With experience, however, the model learns to lower the value of decision thresholds till finally it finds the optimal values. PMID:24904252

  2. Learning to maximize reward rate: a model based on semi-Markov decision processes

    PubMed Central

    Khodadadi, Arash; Fakhari, Pegah; Busemeyer, Jerome R.

    2014-01-01

    When animals have to make a number of decisions during a limited time interval, they face a fundamental problem: how much time they should spend on each decision in order to achieve the maximum possible total outcome. Deliberating more on one decision usually leads to more outcome but less time will remain for other decisions. In the framework of sequential sampling models, the question is how animals learn to set their decision threshold such that the total expected outcome achieved during a limited time is maximized. The aim of this paper is to provide a theoretical framework for answering this question. To this end, we consider an experimental design in which each trial can come from one of the several possible conditions. A condition specifies the difficulty of the trial, the reward, the penalty and so on. We show that to maximize the expected reward during a limited time, the subject should set a separate value of decision threshold for each condition. We propose a model of learning the optimal value of decision thresholds based on the theory of semi-Markov decision processes (SMDP). In our model, the experimental environment is modeled as an SMDP with each condition being a state and the value of decision thresholds being the actions taken in those states. The problem of finding the optimal decision thresholds then is cast as the stochastic optimal control problem of taking actions in each state in the corresponding SMDP such that the average reward rate is maximized. Our model utilizes a biologically plausible learning algorithm to solve this problem. The simulation results show that at the beginning of learning the model choses high values of decision threshold which lead to sub-optimal performance. With experience, however, the model learns to lower the value of decision thresholds till finally it finds the optimal values. PMID:24904252

  3. Second use of transportation batteries: Maximizing the value of batteries for transportation and grid services

    SciTech Connect

    Viswanathan, Vilayanur V.; Kintner-Meyer, Michael CW

    2010-09-30

    Plug-in hybrid electric vehicles (PHEVs) and electric vehicles (EVs) are expected to gain significant market share over the next decade. The economic viability for such vehicles is contingent upon the availability of cost-effective batteries with high power and energy density. For initial commercial success, government subsidies will be highly instrumental in allowing PHEVs to gain a foothold. However, in the long-term, for electric vehicles to be commercially viable, the economics have to be self-sustaining. Towards the end of battery life in the vehicle, the energy capacity left in the battery is not sufficient to provide the designed range for the vehicle. Typically, the automotive manufacturers indicated the need for battery replacement when the remaining energy capacity reaches 70-80%. There is still sufficient power (kW) and energy capacity (kWh) left in the battery to support various grid ancillary services such as balancing, spinning reserve, load following services. As renewable energy penetration increases, the need for such balancing services is expected to increase. This work explores optimality for the replacement of transportation batteries to be subsequently used for grid services. This analysis maximizes the value of an electric vehicle battery to be used as a transportation battery (in its first life) and then as a resource for providing grid services (in its second life). The results are presented across a range of key parameters, such as depth of discharge (DOD), number of batteries used over the life of the vehicle, battery life in vehicle, battery state of health (SOH) at end of life in vehicle and ancillary services rate. The results provide valuable insights for the automotive industry into maximizing the utility and the value of the vehicle batteries in an effort to either reduce the selling price of EVs and PHEVs or maximize the profitability of the emerging electrification of transportation.

  4. Maximizing algebraic connectivity in air transportation networks

    NASA Astrophysics Data System (ADS)

    Wei, Peng

    In air transportation networks the robustness of a network regarding node and link failures is a key factor for its design. An experiment based on the real air transportation network is performed to show that the algebraic connectivity is a good measure for network robustness. Three optimization problems of algebraic connectivity maximization are then formulated in order to find the most robust network design under different constraints. The algebraic connectivity maximization problem with flight routes addition or deletion is first formulated. Three methods to optimize and analyze the network algebraic connectivity are proposed. The Modified Greedy Perturbation Algorithm (MGP) provides a sub-optimal solution in a fast iterative manner. The Weighted Tabu Search (WTS) is designed to offer a near optimal solution with longer running time. The relaxed semi-definite programming (SDP) is used to set a performance upper bound and three rounding techniques are discussed to find the feasible solution. The simulation results present the trade-off among the three methods. The case study on two air transportation networks of Virgin America and Southwest Airlines show that the developed methods can be applied in real world large scale networks. The algebraic connectivity maximization problem is extended by adding the leg number constraint, which considers the traveler's tolerance for the total connecting stops. The Binary Semi-Definite Programming (BSDP) with cutting plane method provides the optimal solution. The tabu search and 2-opt search heuristics can find the optimal solution in small scale networks and the near optimal solution in large scale networks. The third algebraic connectivity maximization problem with operating cost constraint is formulated. When the total operating cost budget is given, the number of the edges to be added is not fixed. Each edge weight needs to be calculated instead of being pre-determined. It is illustrated that the edge addition and the weight assignment can not be studied separately for the problem with operating cost constraint. Therefore a relaxed SDP method with golden section search is developed to solve both at the same time. The cluster decomposition is utilized to solve large scale networks.

  5. A Superintendent's High Expectations

    ERIC Educational Resources Information Center

    Pascopella, Angela

    2009-01-01

    This article profiles Wanda Bamberg, superintendent of the Aldine (Texas) Independent School District. Bamberg is used to high expectations regardless of the circumstances. She is a firecracker of sorts who talks much and expects much from her staff members, teachers, and students, who are mostly at-risk, Black and Hispanic, and economically…

  6. Outside the Expected.

    ERIC Educational Resources Information Center

    Dienstfrey, Harris

    1968-01-01

    In examining the findings of "Pygmalion in the Classroom," an experimental study of the positive effects of favorable teacher expectations on the intellectual development of disadvantaged elementary school students, this review speculates about why the experimental students, whom the teachers expected to improve, and the control students, who were

  7. Reflections on Expectations

    ERIC Educational Resources Information Center

    Santini, Joseph

    2014-01-01

    This article describes a teachers reflections on the matter of student expectations. Santini begins with a common understanding of the "Pygmalion effect" from research projects conducted in earlier years that intimated "people's expectations could influence other people in the world around them." In the world of deaf

  8. An Unexpected Expected Value.

    ERIC Educational Resources Information Center

    Schwartzman, Steven

    1993-01-01

    Discusses the surprising result that the expected number of marbles of one color drawn from a set of marbles of two colors after two draws without replacement is the same as the expected number of that color marble after two draws with replacement. Presents mathematical models to help explain this phenomenon. (MDH)

  9. Knowledge discovery by accuracy maximization.

    PubMed

    Cacciatore, Stefano; Luchinat, Claudio; Tenori, Leonardo

    2014-04-01

    Here we describe KODAMA (knowledge discovery by accuracy maximization), an unsupervised and semisupervised learning algorithm that performs feature extraction from noisy and high-dimensional data. Unlike other data mining methods, the peculiarity of KODAMA is that it is driven by an integrated procedure of cross-validation of the results. The discovery of a local manifold's topology is led by a classifier through a Monte Carlo procedure of maximization of cross-validated predictive accuracy. Briefly, our approach differs from previous methods in that it has an integrated procedure of validation of the results. In this way, the method ensures the highest robustness of the obtained solution. This robustness is demonstrated on experimental datasets of gene expression and metabolomics, where KODAMA compares favorably with other existing feature extraction methods. KODAMA is then applied to an astronomical dataset, revealing unexpected features. Interesting and not easily predictable features are also found in the analysis of the State of the Union speeches by American presidents: KODAMA reveals an abrupt linguistic transition sharply separating all post-Reagan from all pre-Reagan speeches. The transition occurs during Reagan's presidency and not from its beginning. PMID:24706821

  10. Knowledge discovery by accuracy maximization

    PubMed Central

    Cacciatore, Stefano; Luchinat, Claudio; Tenori, Leonardo

    2014-01-01

    Here we describe KODAMA (knowledge discovery by accuracy maximization), an unsupervised and semisupervised learning algorithm that performs feature extraction from noisy and high-dimensional data. Unlike other data mining methods, the peculiarity of KODAMA is that it is driven by an integrated procedure of cross-validation of the results. The discovery of a local manifolds topology is led by a classifier through a Monte Carlo procedure of maximization of cross-validated predictive accuracy. Briefly, our approach differs from previous methods in that it has an integrated procedure of validation of the results. In this way, the method ensures the highest robustness of the obtained solution. This robustness is demonstrated on experimental datasets of gene expression and metabolomics, where KODAMA compares favorably with other existing feature extraction methods. KODAMA is then applied to an astronomical dataset, revealing unexpected features. Interesting and not easily predictable features are also found in the analysis of the State of the Union speeches by American presidents: KODAMA reveals an abrupt linguistic transition sharply separating all post-Reagan from all pre-Reagan speeches. The transition occurs during Reagans presidency and not from its beginning. PMID:24706821

  11. Maximally coherent mixed states: Complementarity between maximal coherence and mixedness

    NASA Astrophysics Data System (ADS)

    Singh, Uttam; Bera, Manabendra Nath; Dhar, Himadri Shekhar; Pati, Arun Kumar

    2015-05-01

    Quantum coherence is a key element in topical research on quantum resource theories and a primary facilitator for design and implementation of quantum technologies. However, the resourcefulness of quantum coherence is severely restricted by environmental noise, which is indicated by the loss of information in a quantum system, measured in terms of its purity. In this work, we derive the limits imposed by the mixedness of a quantum system on the amount of quantum coherence that it can possess. We obtain an analytical trade-off between the two quantities that upperbound the maximum quantum coherence for fixed mixedness in a system. This gives rise to a class of quantum states, "maximally coherent mixed states," whose coherence cannot be increased further under any purity-preserving operation. For the above class of states, quantum coherence and mixedness satisfy a complementarity relation, which is crucial to understand the interplay between a resource and noise in open quantum systems.

  12. On learning statistical mixtures maximizing the complete likelihood

    NASA Astrophysics Data System (ADS)

    Nielsen, Frank

    2015-01-01

    Statistical mixtures are semi-parametric models ubiquitously met in data science since they can universally model smooth densities arbitrarily closely. Finite mixtures are usually inferred from data using the celebrated Expectation-Maximization framework that locally iteratively maximizes the incomplete likelihood by assigning softly data to mixture components. In this paper, we present a novel methodology to infer mixtures by transforming the learning problem into a sequence of geometric center-based hard clustering problems that provably maximizes monotonically the complete likelihood. Our versatile method is fast and uses low memory footprint: The core inner steps can be implemented using various generalized k-means type heuristics. Thus we can leverage recent results on clustering to mixture learning. In particular, for mixtures of singly-parametric distributions including for example the Rayleigh, Weibull, or Poisson distributions, we show how to use dynamic programming to solve exactly the inner geometric clustering problems. We discuss on several extensions of the methodology.

  13. Ventromedial frontal lobe damage disrupts value maximization in humans.

    PubMed

    Camille, Nathalie; Griffiths, Cathryn A; Vo, Khoi; Fellows, Lesley K; Kable, Joseph W

    2011-05-18

    Recent work in neuroeconomics has shown that regions in orbitofrontal and medial prefrontal cortex encode the subjective value of different options during choice. However, these electrophysiological and neuroimaging studies cannot demonstrate whether such signals are necessary for value-maximizing choices. Here we used a paradigm developed in experimental economics to empirically measure and quantify violations of utility theory in humans with damage to the ventromedial frontal lobe (VMF). We show that people with such damage are more likely to make choices that violate the generalized axiom of revealed preference, which is the one necessary and sufficient condition for choices to be consistent with value maximization. These results demonstrate that the VMF plays a critical role in value-maximizing choice. PMID:21593337

  14. Maximal acceleration and radiative processes

    NASA Astrophysics Data System (ADS)

    Papini, Giorgio

    2015-08-01

    We derive the radiation characteristics of an accelerated, charged particle in a model due to Caianiello in which the proper acceleration of a particle of mass m has the upper limit 𝒜m = 2mc3/?. We find two power laws, one applicable to lower accelerations, the other more suitable for accelerations closer to 𝒜m and to the related physical singularity in the Ricci scalar. Geometrical constraints and power spectra are also discussed. By comparing the power laws due to the maximal acceleration (MA) with that for particles in gravitational fields, we find that the model of Caianiello allows, in principle, the use of charged particles as tools to distinguish inertial from gravitational fields locally.

  15. Performance expectation plan

    SciTech Connect

    Ray, P.E.

    1998-09-04

    This document outlines the significant accomplishments of fiscal year 1998 for the Tank Waste Remediation System (TWRS) Project Hanford Management Contract (PHMC) team. Opportunities for improvement to better meet some performance expectations have been identified. The PHMC has performed at an excellent level in administration of leadership, planning, and technical direction. The contractor has met and made notable improvement of attaining customer satisfaction in mission execution. This document includes the team`s recommendation that the PHMC TWRS Performance Expectation Plan evaluation rating for fiscal year 1998 be an Excellent.

  16. Maximal dinucleotide and trinucleotide circular codes.

    PubMed

    Michel, Christian J; Pellegrini, Marco; Pirillo, Giuseppe

    2016-01-21

    We determine here the number and the list of maximal dinucleotide and trinucleotide circular codes. We prove that there is no maximal dinucleotide circular code having strictly less than 6 elements (maximum size of dinucleotide circular codes). On the other hand, a computer calculus shows that there are maximal trinucleotide circular codes with less than 20 elements (maximum size of trinucleotide circular codes). More precisely, there are maximal trinucleotide circular codes with 14, 15, 16, 17, 18 and 19 elements and no maximal trinucleotide circular code having less than 14 elements. We give the same information for the maximal self-complementary dinucleotide and trinucleotide circular codes. The amino acid distribution of maximal trinucleotide circular codes is also determined. PMID:26382231

  17. Behavior, Expectations and Status

    ERIC Educational Resources Information Center

    Webster, Jr, Murray; Rashotte, Lisa Slattery

    2010-01-01

    We predict effects of behavior patterns and status on performance expectations and group inequality using an integrated theory developed by Fisek, Berger and Norman (1991). We next test those predictions using new experimental techniques we developed to control behavior patterns as independent variables. In a 10-condition experiment, predictions…

  18. Parenting with High Expectations

    ERIC Educational Resources Information Center

    Timperlake, Benna Hull; Sanders, Genelle Timperlake

    2014-01-01

    In some ways raising deaf or hard of hearing children is no different than raising hearing children; expectations must be established and periodically tweaked. Benna Hull Timperlake, who with husband Roger, raised two hearing children in addition to their deaf daughter, Genelle Timperlake Sanders, and Genelle, now a deaf professional, share their…

  19. Great Expectations. [Lesson Plan].

    ERIC Educational Resources Information Center

    Devine, Kelley

    Based on Charles Dickens' novel "Great Expectations," this lesson plan presents activities designed to help students understand the differences between totalitarianism and democracy; and a that a writer of a story considers theme, plot, characters, setting, and point of view. The main activity of the lesson involves students working in groups to…

  20. Maintaining High Expectations

    ERIC Educational Resources Information Center

    Williams, Roger; Williams, Sherry

    2014-01-01

    Author and husband, Roger Williams, is hearing and signs fluently, and author and wife, Sherry Williams, is deaf and uses both speech and signs, although she is most comfortable signing. As parents of six children--deaf and hearing--they are determined to encourage their children to do their best, and they always set their expectations high. They

  1. An expectation maximization framework for an improved ultrasound-based tissue characterization

    NASA Astrophysics Data System (ADS)

    Alessandrini, Martino; Maggio, Simona; Pore, Jonathan; De Marchi, Luca; Speciale, Nicol; Franceschini, Emilie; Bernard, Olivier; Basset, Olivier

    2011-03-01

    Ultrasonic tissue characterization has been gaining increasing attention. This procedure is generally based on the analysis of the echo signal. As the ultrasound echo is degraded by the system Point Spread Function, deconvolution could be employed to provide a tissue response estimate, exploitable for a better characterization. In this context, we present a deconvolution framework expressively designed to improve tissue characterization. Thanks to a new model for tissue reflectivity the proposed framework overcomes limitations associated with standard ones. The performance was evaluated from several tissue-mimicking phantoms. Obtained results show relevant improvements in classification accuracy. From a comparison with standard schemes the superiority of the proposed algorithm was attested.

  2. Modeling population screening process for maximizing throughputs.

    PubMed

    Li, Chunsheng; Capello, Kevin; Jeng, Huai-An; Hauck, Barry; Kramer, Gary H

    2014-05-01

    Following a large-scale radiation emergency, affected populations will need to be screened soon after for potential contamination (external or internal). Effective management of the available resources can help maximize the screening throughputs. This paper reports the modeling results for screening throughputs in a population screening center using a set resource, considering two major variables, the arrival rate (number of people arriving at the screening center per minute) and the contamination probability (the probability of finding a contaminated group). Both the full process (including all sub-processes in a population screening center) and the core process (including only the screening sub-processes: pre-screening, portal monitoring, and whole body counting) were simulated. As expected, for both processes, as the arrival rate increases, the screening center can get overwhelmed. Interestingly, the contamination probability becomes a significant factor for screening throughputs only when the arrival rate becomes high. The results show that following an emergency, when the arrival rate is high, much more resources will need to be deployed to the population screening center or multiple screening centers will need to be established. PMID:24667390

  3. A Maximally Supersymmetric Kondo Model

    SciTech Connect

    Harrison, Sarah; Kachru, Shamit; Torroba, Gonzalo; /Stanford U., Phys. Dept. /SLAC

    2012-02-17

    We study the maximally supersymmetric Kondo model obtained by adding a fermionic impurity to N = 4 supersymmetric Yang-Mills theory. While the original Kondo problem describes a defect interacting with a free Fermi liquid of itinerant electrons, here the ambient theory is an interacting CFT, and this introduces qualitatively new features into the system. The model arises in string theory by considering the intersection of a stack of M D5-branes with a stack of N D3-branes, at a point in the D3 worldvolume. We analyze the theory holographically, and propose a dictionary between the Kondo problem and antisymmetric Wilson loops in N = 4 SYM. We perform an explicit calculation of the D5 fluctuations in the D3 geometry and determine the spectrum of defect operators. This establishes the stability of the Kondo fixed point together with its basic thermodynamic properties. Known supergravity solutions for Wilson loops allow us to go beyond the probe approximation: the D5s disappear and are replaced by three-form flux piercing a new topologically non-trivial S3 in the corrected geometry. This describes the Kondo model in terms of a geometric transition. A dual matrix model reflects the basic properties of the corrected gravity solution in its eigenvalue distribution.

  4. Maximizing the optical network capacity

    PubMed Central

    Bayvel, Polina; Maher, Robert; Liga, Gabriele; Shevchenko, Nikita A.; Lavery, Domaniç; Killey, Robert I.

    2016-01-01

    Most of the digital data transmitted are carried by optical fibres, forming the great part of the national and international communication infrastructure. The information-carrying capacity of these networks has increased vastly over the past decades through the introduction of wavelength division multiplexing, advanced modulation formats, digital signal processing and improved optical fibre and amplifier technology. These developments sparked the communication revolution and the growth of the Internet, and have created an illusion of infinite capacity being available. But as the volume of data continues to increase, is there a limit to the capacity of an optical fibre communication channel? The optical fibre channel is nonlinear, and the intensity-dependent Kerr nonlinearity limit has been suggested as a fundamental limit to optical fibre capacity. Current research is focused on whether this is the case, and on linear and nonlinear techniques, both optical and electronic, to understand, unlock and maximize the capacity of optical communications in the nonlinear regime. This paper describes some of them and discusses future prospects for success in the quest for capacity. PMID:26809572

  5. Maximizing the optical network capacity.

    PubMed

    Bayvel, Polina; Maher, Robert; Xu, Tianhua; Liga, Gabriele; Shevchenko, Nikita A; Lavery, Domaniç; Alvarado, Alex; Killey, Robert I

    2016-03-01

    Most of the digital data transmitted are carried by optical fibres, forming the great part of the national and international communication infrastructure. The information-carrying capacity of these networks has increased vastly over the past decades through the introduction of wavelength division multiplexing, advanced modulation formats, digital signal processing and improved optical fibre and amplifier technology. These developments sparked the communication revolution and the growth of the Internet, and have created an illusion of infinite capacity being available. But as the volume of data continues to increase, is there a limit to the capacity of an optical fibre communication channel? The optical fibre channel is nonlinear, and the intensity-dependent Kerr nonlinearity limit has been suggested as a fundamental limit to optical fibre capacity. Current research is focused on whether this is the case, and on linear and nonlinear techniques, both optical and electronic, to understand, unlock and maximize the capacity of optical communications in the nonlinear regime. This paper describes some of them and discusses future prospects for success in the quest for capacity. PMID:26809572

  6. Maximal Oxygen Intake and Maximal Work Performance of Active College Women.

    ERIC Educational Resources Information Center

    Higgs, Susanne L.

    Maximal oxygen intake and associated physiological variables were measured during strenuous exercise on women subjects (N=20 physical education majors). Following assessment of maximal oxygen intake, all subjects underwent a performance test at the work level which had elicited their maximal oxygen intake. Mean maximal oxygen intake was 41.32

  7. Maximally Expressive Modeling of Operations Tasks

    NASA Technical Reports Server (NTRS)

    Jaap, John; Richardson, Lea; Davis, Elizabeth

    2002-01-01

    Planning and scheduling systems organize "tasks" into a timeline or schedule. The tasks are defined within the scheduling system in logical containers called models. The dictionary might define a model of this type as "a system of things and relations satisfying a set of rules that, when applied to the things and relations, produce certainty about the tasks that are being modeled." One challenging domain for a planning and scheduling system is the operation of on-board experiments for the International Space Station. In these experiments, the equipment used is among the most complex hardware ever developed, the information sought is at the cutting edge of scientific endeavor, and the procedures are intricate and exacting. Scheduling is made more difficult by a scarcity of station resources. The models to be fed into the scheduler must describe both the complexity of the experiments and procedures (to ensure a valid schedule) and the flexibilities of the procedures and the equipment (to effectively utilize available resources). Clearly, scheduling International Space Station experiment operations calls for a "maximally expressive" modeling schema.

  8. Inflation in maximal gauged supergravities

    SciTech Connect

    Kodama, Hideo; Nozawa, Masato

    2015-05-18

    We discuss the dynamics of multiple scalar fields and the possibility of realistic inflation in the maximal gauged supergravity. In this paper, we address this problem in the framework of recently discovered 1-parameter deformation of SO(4,4) and SO(5,3) dyonic gaugings, for which the base point of the scalar manifold corresponds to an unstable de Sitter critical point. In the gauge-field frame where the embedding tensor takes the value in the sum of the 36 and 36’ representations of SL(8), we present a scheme that allows us to derive an analytic expression for the scalar potential. With the help of this formalism, we derive the full potential and gauge coupling functions in analytic forms for the SO(3)×SO(3)-invariant subsectors of SO(4,4) and SO(5,3) gaugings, and argue that there exist no new critical points in addition to those discovered so far. For the SO(4,4) gauging, we also study the behavior of 6-dimensional scalar fields in this sector near the Dall’Agata-Inverso de Sitter critical point at which the negative eigenvalue of the scalar mass square with the largest modulus goes to zero as the deformation parameter s approaches a critical value s{sub c}. We find that when the deformation parameter s is taken sufficiently close to the critical value, inflation lasts more than 60 e-folds even if the initial point of the inflaton allows an O(0.1) deviation in Planck units from the Dall’Agata-Inverso critical point. It turns out that the spectral index n{sub s} of the curvature perturbation at the time of the 60 e-folding number is always about 0.96 and within the 1σ range n{sub s}=0.9639±0.0047 obtained by Planck, irrespective of the value of the η parameter at the critical saddle point. The tensor-scalar ratio predicted by this model is around 10{sup −3} and is close to the value in the Starobinsky model.

  9. Inflation in maximal gauged supergravities

    NASA Astrophysics Data System (ADS)

    Kodama, Hideo; Nozawa, Masato

    2015-05-01

    We discuss the dynamics of multiple scalar fields and the possibility of realistic inflation in the maximal gauged supergravity. In this paper, we address this problem in the framework of recently discovered 1-parameter deformation of SO(4,4) and SO(5,3) dyonic gaugings, for which the base point of the scalar manifold corresponds to an unstable de Sitter critical point. In the gauge-field frame where the embedding tensor takes the value in the sum of the {36} and {36'} representations of SL(8), we present a scheme that allows us to derive an analytic expression for the scalar potential. With the help of this formalism, we derive the full potential and gauge coupling functions in analytic forms for the SO(3)× SO(3)-invariant subsectors of SO(4,4) and SO(5,3) gaugings, and argue that there exist no new critical points in addition to those discovered so far. For the SO(4,4) gauging, we also study the behavior of 6-dimensional scalar fields in this sector near the Dall'Agata-Inverso de Sitter critical point at which the negative eigenvalue of the scalar mass square with the largest modulus goes to zero as the deformation parameter s approaches a critical value sc. We find that when the deformation parameter s is taken sufficiently close to the critical value, inflation lasts more than 60 e-folds even if the initial point of the inflaton allows an O(0.1) deviation in Planck units from the Dall'Agata-Inverso critical point. It turns out that the spectral index ns of the curvature perturbation at the time of the 60 e-folding number is always about 0.96 and within the 1σ range ns=0.9639±0.0047 obtained by Planck, irrespective of the value of the η parameter at the critical saddle point. The tensor-scalar ratio predicted by this model is around 10-3 and is close to the value in the Starobinsky model.

  10. Dynamics with Expectations

    NASA Astrophysics Data System (ADS)

    Glance, Natalie Sandrine

    The study of dynamics with expectations is relevant whenever the entities or "agents" comprising a complex system take into account possible future states when making decisions in the present. Goal-seeking agents form plans to achieve their ends based on their knowledge of causes, their memory of the past, their predictions for the future, as well as on their biases and their beliefs. A dynamical formulation of agent interactions requires a different approach when the behavior of the entities depends on their beliefs and knowledge as well as on the rules governing the evolution of the system. The agents' predictions for the future must enter explicitly into the dynamical rules governing the evolution of the system. This thesis examines the behavior of two dynamical systems in particular. The first, referred to as a computational ecosystem, is composed of a collection of processes, or agents, that compete among themselves for limited resources. The analytical tools of nonlinear dynamics and the modern-day aid of numerical integration via computer are employed to map out the behavioral regimes of the system first when the external environment changes over time, and second when the individual agents incorporate expectations about the future into their decisions. In the second part, a system composed of interacting agents whose individual goals conflict with the overall good of the group is studied both analytically and through computer simulations. It is shown how spontaneous cooperation can be achieved if the agents take into account their expectations about the future when making their choices in the present. Further, the system can remain trapped in a metastable state for long periods of time; eventually, rare large fluctuations occur due to uncertain information that can cause a transition to the global equilibrium. The effects of ultrametric group structure and diversity on the dynamics of cooperation are also elucidated. Specifically, it is seen how the interplay between evolving group structure and the number of agents cooperating introduces new dynamical pathways to cooperation.

  11. Post-Secondary Expectations and Educational Attainment

    ERIC Educational Resources Information Center

    Sciarra, Daniel T.; Ambrosino, Katherine E.

    2011-01-01

    This study utilized student, teacher, and parent expectations during high school to analyze their predictive effect on post-secondary education status two years after scheduled graduation. The sample included 5,353 students, parents and teachers who participated in the Educational Longitudinal Study (ELS; 2002-2006). The researchers analyzed data…

  12. Specificity of a Maximal Step Exercise Test

    ERIC Educational Resources Information Center

    Darby, Lynn A.; Marsh, Jennifer L.; Shewokis, Patricia A.; Pohlman, Roberta L.

    2007-01-01

    To adhere to the principle of "exercise specificity" exercise testing should be completed using the same physical activity that is performed during exercise training. The present study was designed to assess whether aerobic step exercisers have a greater maximal oxygen consumption (max VO sub 2) when tested using an activity specific, maximal step

  13. Maximizing measures for endomorphisms of the circle

    NASA Astrophysics Data System (ADS)

    Tal, Fbio Armando; Addas-Zanata, Salvador

    2008-10-01

    We study a given fixed continuous function \\phi:S^1\\to \\mathbb{R} and an endomorphism f : S1 ? S1, whose f-invariant probability measures maximize \\int \\phi\\,\\rmd\\mu . We prove that the set of endomorphisms having a phi maximizing invariant measure supported on a periodic orbit is \\mathcal{C}_0 dense.

  14. Diurnal Variations in Maximal Oxygen Uptake.

    ERIC Educational Resources Information Center

    McClellan, Powell D.

    A study attempted to determine if diurnal (daily cyclical) variations were present during maximal exercise. The subjects' (30 female undergraduate physical education majors) oxygen consumption and heart rates were monitored while they walked on a treadmill on which the grade was raised every minute. Each subject was tested for maximal oxygen

  15. Specificity of a Maximal Step Exercise Test

    ERIC Educational Resources Information Center

    Darby, Lynn A.; Marsh, Jennifer L.; Shewokis, Patricia A.; Pohlman, Roberta L.

    2007-01-01

    To adhere to the principle of "exercise specificity" exercise testing should be completed using the same physical activity that is performed during exercise training. The present study was designed to assess whether aerobic step exercisers have a greater maximal oxygen consumption (max VO sub 2) when tested using an activity specific, maximal step…

  16. Statistical mechanics of maximal independent sets

    NASA Astrophysics Data System (ADS)

    Dall'Asta, Luca; Pin, Paolo; Ramezanpour, Abolfazl

    2009-12-01

    The graph theoretic concept of maximal independent set arises in several practical problems in computer science as well as in game theory. A maximal independent set is defined by the set of occupied nodes that satisfy some packing and covering constraints. It is known that finding minimum and maximum-density maximal independent sets are hard optimization problems. In this paper, we use cavity method of statistical physics and Monte Carlo simulations to study the corresponding constraint satisfaction problem on random graphs. We obtain the entropy of maximal independent sets within the replica symmetric and one-step replica symmetry breaking frameworks, shedding light on the metric structure of the landscape of solutions and suggesting a class of possible algorithms. This is of particular relevance for the application to the study of strategic interactions in social and economic networks, where maximal independent sets correspond to pure Nash equilibria of a graphical game of public goods allocation.

  17. Beyond my wildest expectations.

    PubMed

    Nester, Eugene

    2014-01-01

    With support from my parents, I fulfilled their and my expectations of graduating from college and becoming a scientist. My scientific career has focused on two organisms, Bacillus subtilis and Agrobacterium tumefaciens, and two experimental systems, aromatic amino acid synthesis and DNA transfer in bacteria and plants. Studies on B. subtilis emphasized the genetics and biochemistry of aromatic amino acid synthesis and the characterization of competence in DNA transformation. I carried out both as a postdoc at Stanford with Josh Lederberg. At the University of Washington, I continued these studies and then investigated how Agrobacterium transforms plant cells. In collaboration, Milt Gordon, Mary-Dell Chilton, and I found that this bacterium could transfer a piece of its plasmid into plant cells and thereby modify their properties. This discovery opened up a host of intriguing questions that we have tried to answer over the last 35 years. PMID:25208299

  18. The futility of utility: how market dynamics marginalize Adam Smith

    NASA Astrophysics Data System (ADS)

    McCauley, Joseph L.

    2000-10-01

    Economic theorizing is based on the postulated, nonempiric notion of utility. Economists assume that prices, dynamics, and market equilibria are supposed to be derived from utility. The results are supposed to represent mathematically the stabilizing action of Adam Smith's invisible hand. In deterministic excess demand dynamics I show the following. A utility function generally does not exist mathematically due to nonintegrable dynamics when production/investment are accounted for, resolving Mirowski's thesis. Price as a function of demand does not exist mathematically either. All equilibria are unstable. I then explain how deterministic chaos can be distinguished from random noise at short times. In the generalization to liquid markets and finance theory described by stochastic excess demand dynamics, I also show the following. Market price distributions cannot be rescaled to describe price movements as equilibrium fluctuations about a systematic drift in price. Utility maximization does not describe equilibrium. Maximization of the Gibbs entropy of the observed price distribution of an asset would describe equilibrium, if equilibrium could be achieved, but equilibrium does not describe real, liquid markets (stocks, bonds, foreign exchange). There are three inconsistent definitions of equilibrium used in economics and finance, only one of which is correct. Prices in unregulated free markets are unstable against both noise and rising or falling expectations: Adam Smith's stabilizing invisible hand does not exist, either in mathematical models of liquid market data, or in real market data.

  19. Glioblastoma: changing expectations?

    PubMed

    Arribas Alpuente, Leoncio; Menndez Lpez, Antonio; Yay Tur, Ricardo

    2011-04-01

    Glioblastoma (GB) represents the most aggressive glioma in the adult population. Despite recent research efforts, the prognosis of patients with GB has remained dismal. Lately, the knowledge of genetic information about gliomagenesis has increased; we even have a classification of the genetic expression of the tumour. The main problem is that at the moment we do not have any therapeutical resources to help us better treat these tumours, as we can do, with others tumours like breast, lung and colorectal cancer. We have also improved on diagnostic imaging, especially with the new MRI sequences; we can now better define the characteristics of the tumour area and the surrounding brain structures, allowing us to adjust resections. Thanks to the most advanced surgery techniques, such as neuronavigation, intraoperative control of the nervous function and the tumour volume, the neurosurgeon is able to complete tumour exeresis with less morbidity. These imaging techniques allow the radiation oncologist to better contour the irradiation target volume, the structures and the organs at risk, to diminish the irradiation of apparently healthy tissue. Nowadays, knowledge of brain stem cells provides new expectations for future treatments. Novel targeted agents such as bevacizumab, imatinib, erlotinib, temsirolimus, immunotherapy, cilengitide, talampanel, etc. are helping classical chemotherapeutic agents, like temozolomide, to achieve an increase in overall survival. The main objective is to improve median overall survival, which is currently between 9 and 12 months, with a good quality of life, measured by the ability to carry out daily life activities. PMID:21493184

  20. New standard exceeds expectations

    SciTech Connect

    Bennett, M.J. )

    1993-08-01

    The new ASTM environmental due diligence standard is delivering far more than expected when it was conceived in 1990. Its use goes well beyond the relatively narrow legal liability protection that was the primary goal in its development. The real estate industry, spearheaded by the lending community, was preoccupied with environmental risk and liability. Lenders throughout the concept's evolution have been at the forefront in defining environmental due diligence. The lender liability rule is intended to protect property owners from CERCLA liability for property they own or companies they manage (for example, as a result of foreclosure). The new site assessment standard increasingly is considered a benchmark for prudent environmental due diligence in the interest of risk management, not legal liability. The focus on risk management, including collateral devaluation and corporate credit risk, are becoming dominant areas of policy focus in the lending industry. Lenders now are revising their policies to incorporate transactions beyond issues of real estate, in which a company's economic viability and ability to service debt could be impacted by an environmental problem unrelated to property transfers.

  1. Sociology of Low Expectations

    PubMed Central

    Samuel, Gabrielle; Williams, Clare

    2015-01-01

    Social scientists have drawn attention to the role of hype and optimistic visions of the future in providing momentum to biomedical innovation projects by encouraging innovation alliances. In this article, we show how less optimistic, uncertain, and modest visions of the future can also provide innovation projects with momentum. Scholars have highlighted the need for clinicians to carefully manage the expectations of their prospective patients. Using the example of a pioneering clinical team providing deep brain stimulation to children and young people with movement disorders, we show how clinicians confront this requirement by drawing on their professional knowledge and clinical expertise to construct visions of the future with their prospective patients; visions which are personalized, modest, and tainted with uncertainty. We refer to this vision-constructing work as recalibration, and we argue that recalibration enables clinicians to manage the tension between the highly optimistic and hyped visions of the future that surround novel biomedical interventions, and the exigencies of delivering those interventions in a clinical setting. Drawing on work from science and technology studies, we suggest that recalibration enrolls patients in an innovation alliance by creating a shared understanding of how the “effectiveness” of an innovation shall be judged. PMID:26527846

  2. Expectations and speech intelligibility.

    PubMed

    Babel, Molly; Russell, Jamie

    2015-05-01

    Socio-indexical cues and paralinguistic information are often beneficial to speech processing as this information assists listeners in parsing the speech stream. Associations that particular populations speak in a certain speech style can, however, make it such that socio-indexical cues have a cost. In this study, native speakers of Canadian English who identify as Chinese Canadian and White Canadian read sentences that were presented to listeners in noise. Half of the sentences were presented with a visual-prime in the form of a photo of the speaker and half were presented in control trials with fixation crosses. Sentences produced by Chinese Canadians showed an intelligibility cost in the face-prime condition, whereas sentences produced by White Canadians did not. In an accentedness rating task, listeners rated White Canadians as less accented in the face-prime trials, but Chinese Canadians showed no such change in perceived accentedness. These results suggest a misalignment between an expected and an observed speech signal for the face-prime trials, which indicates that social information about a speaker can trigger linguistic associations that come with processing benefits and costs. PMID:25994710

  3. The boundary value problem for maximal hypersurfaces.

    PubMed

    Flaherty, F J

    1979-10-01

    A spacelike hypersurface (condimension 1) in a Lorentzian manifold is called a maximal surface if it extremizes the hypervolume functional. Although maximal surfaces are superficially analogous to minimal hypersurfaces in Riemannian geometry, their properties can be dramatically different, as can be seen from the validity of Bernstein's theorem in all dimensions [Cheng, S.-Y. & Yau, S.-T. (1976) Ann. Math. 104, 407-419]. Here we establish a point of contact between maximal surfaces and minimal surfaces by solving the Dirichlet problem for acausal boundary data but using boundary curvature conditions similar to those of H. Jenkins and J. Serrin [(1968) J. Reine Angew. Math. 229, 170-187]. PMID:16578756

  4. Comparative aspects of maximal oxygen consumption.

    PubMed

    Dejours, P

    1990-01-01

    The respiratory system, that is the set of compartments interposed between the cells and the environment, is best studied among mammals. Across the compartments there exist net fluxes of O2 and CO2, the intensities of which depend on the animal's size. In steady state, at rest, the relation between O2 flux and body size has the form of an allometric equation in which the O2 consumption, MO2, is proportional to body mass with an exponent or scaling factor of about 0.75 (Brody, 1945; Kleiber, 1961). The principal experimental methods to force animals to maximal MO2 are cold exposure and exercise. According to the concepts of physiological time, strenuous exercise to reach maximal MO2 should be shorter in small animals than in large ones. The scaling factor for maximal MO2 seems to be higher than standard conditions; in other terms, large exercising mammals may increase their maximal MO2 more than small animals. The comparative approach of maximal MO2 is a powerful tool for finding where in the respiratory system the strictures or bottlenecks are which may limit O2 consumption. According to the ambient or organismal conditions (pressure, temperature, posture, nutrition), the site of the stricture may vary. As far as is known, the O2 consumption of the whole human body, in standard conditions as well as in maximal activity, and for a given mass, is such that, compared to other mammals, the human exhibits no species-specific characteristics. PMID:2218097

  5. Formation Control of the MAXIM L2 Libration Orbit Mission

    NASA Technical Reports Server (NTRS)

    Folta, David; Hartman, Kate; Howell, Kathleen; Marchand, Belinda

    2004-01-01

    The Micro-Arcsecond X-ray Imaging Mission (MAXIM), a proposed concept for the Structure and Evolution of the Universe (SEU) Black Hole Imager mission, is designed to make a ten million-fold improvement in X-ray image clarity of celestial objects by providing better than 0.1 micro-arcsecond imaging. Currently the mission architecture comprises 25 spacecraft, 24 as optics modules and one as the detector, which will form sparse sub-apertures of a grazing incidence X-ray interferometer covering the 0.3-10 keV bandpass. This formation must allow for long duration continuous science observations and also for reconfiguration that permits re-pointing of the formation. To achieve these mission goals, the formation is required to cooperatively point at desired targets. Once pointed, the individual elements of the MAXIM formation must remain stable, maintaining their relative positions and attitudes below a critical threshold. These pointing and formation stability requirements impact the control and design of the formation. In this paper, we provide analysis of control efforts that are dependent upon the stability and the configuration and dimensions of the MAXIM formation. We emphasize the utilization of natural motions in the Lagrangian regions to minimize the control efforts and we address continuous control via input feedback linearization (IFL). Results provide control cost, configuration options, and capabilities as guidelines for the development of this complex mission.

  6. Great Expectations: Temporal Expectation Modulates Perceptual Processing Speed

    ERIC Educational Resources Information Center

    Vangkilde, Signe; Coull, Jennifer T.; Bundesen, Claus

    2012-01-01

    In a crowded dynamic world, temporal expectations guide our attention in time. Prior investigations have consistently demonstrated that temporal expectations speed motor behavior. We explore effects of temporal expectation on "perceptual" speed in three nonspeeded, cued recognition paradigms. Different hazard rate functions for the cue-stimulus

  7. Expecting ourselves to expect: the Bayesian brain as a projector.

    PubMed

    Dennett, Daniel C

    2013-06-01

    Clark's essay lays the foundation for a Bayesian account of the "projection" of consciously perceived properties: The expectations that our brains test against inputs concern the particular affordances that evolution has designed us to care about, including especially expectations of our own expectations. PMID:23663550

  8. Dialysis centers - what to expect

    MedlinePLUS

    Artificial kidneys - dialysis centers - what to expect; Dialysis - what to expect; Renal replacement therapy - dialysis centers - what ... excess fluid. The filter is sometimes called an artificial kidney. Once you arrive at the center, trained ...

  9. Resources and energetics determined dinosaur maximal size

    PubMed Central

    McNab, Brian K.

    2009-01-01

    Some dinosaurs reached masses that were ≈8 times those of the largest, ecologically equivalent terrestrial mammals. The factors most responsible for setting the maximal body size of vertebrates are resource quality and quantity, as modified by the mobility of the consumer, and the vertebrate's rate of energy expenditure. If the food intake of the largest herbivorous mammals defines the maximal rate at which plant resources can be consumed in terrestrial environments and if that limit applied to dinosaurs, then the large size of sauropods occurred because they expended energy in the field at rates extrapolated from those of varanid lizards, which are ≈22% of the rates in mammals and 3.6 times the rates of other lizards of equal size. Of 2 species having the same energy income, the species that uses the most energy for mass-independent maintenance of necessity has a smaller size. The larger mass found in some marine mammals reflects a greater resource abundance in marine environments. The presumptively low energy expenditures of dinosaurs potentially permitted Mesozoic communities to support dinosaur biomasses that were up to 5 times those found in mammalian herbivores in Africa today. The maximal size of predatory theropods was ≈8 tons, which if it reflected the maximal capacity to consume vertebrates in terrestrial environments, corresponds in predatory mammals to a maximal mass less than a ton, which is what is observed. Some coelurosaurs may have evolved endothermy in association with the evolution of feathered insulation and a small mass. PMID:19581600

  10. Getting used to it: the adaptive global utility model.

    PubMed

    Bradford, W David; Dolan, Paul

    2010-12-01

    This paper expands the standard model of utility maximization to endogenize the ubiquitous phenomenon of adaptation. We assume that total utility is an aggregate function of the utility associated with different domains of life, with relative weights that are optimized according to the effort that the individual expends on producing utility in each domain. Comparative statics from the general maximization problem demonstrate that the traditional Slutsky equation should incorporate an additional response term to account for adaptation processes. Our adaptive global utility maximization model can be used to explain responses to changes in health. PMID:20728231

  11. Measuring Alcohol Expectancies in Youth

    ERIC Educational Resources Information Center

    Randolph, Karen A.; Gerend, Mary A.; Miller, Brenda A.

    2006-01-01

    Beliefs about the consequences of using alcohol, alcohol expectancies, are powerful predictors of underage drinking. The Alcohol Expectancies Questionnaire-Adolescent form (AEQ-A) has been widely used to measure expectancies in youth. Despite its broad use, the factor structure of the AEQ-A has not been firmly established. It is also not known…

  12. Quantum theory allows for absolute maximal contextuality

    NASA Astrophysics Data System (ADS)

    Amaral, Barbara; Cunha, Marcelo Terra; Cabello, Adn

    2015-12-01

    Contextuality is a fundamental feature of quantum theory and a necessary resource for quantum computation and communication. It is therefore important to investigate how large contextuality can be in quantum theory. Linear contextuality witnesses can be expressed as a sum S of n probabilities, and the independence number ? and the Tsirelson-like number ? of the corresponding exclusivity graph are, respectively, the maximum of S for noncontextual theories and for the theory under consideration. A theory allows for absolute maximal contextuality if it has scenarios in which ? /? approaches n . Here we show that quantum theory allows for absolute maximal contextuality despite what is suggested by the examination of the quantum violations of Bell and noncontextuality inequalities considered in the past. Our proof is not constructive and does not single out explicit scenarios. Nevertheless, we identify scenarios in which quantum theory allows for almost-absolute-maximal contextuality.

  13. Massive nonplanar two-loop maximal unitarity

    NASA Astrophysics Data System (ADS)

    Sgaard, Mads; Zhang, Yang

    2014-12-01

    We explore maximal unitarity for nonplanar two-loop integrals with up to four massive external legs. In this framework, the amplitude is reduced to a basis of master integrals whose coefficients are extracted from maximal cuts. The hepta-cut of the nonplanar double box defines a nodal algebraic curve associated with a multiply pinched genus-3 Riemann surface. All possible configurations of external masses are covered by two distinct topological pictures in which the curve decomposes into either six or eight Riemann spheres. The procedure relies on consistency equations based on vanishing of integrals of total derivatives and Levi-Civita contractions. Our analysis indicates that these constraints are governed by the global structure of the maximal cut. Lastly, we present an algorithm for computing generalized cuts of massive integrals with higher powers of propagators based on the Bezoutian matrix method.

  14. An information maximization model of eye movements

    NASA Technical Reports Server (NTRS)

    Renninger, Laura Walker; Coughlan, James; Verghese, Preeti; Malik, Jitendra

    2005-01-01

    We propose a sequential information maximization model as a general strategy for programming eye movements. The model reconstructs high-resolution visual information from a sequence of fixations, taking into account the fall-off in resolution from the fovea to the periphery. From this framework we get a simple rule for predicting fixation sequences: after each fixation, fixate next at the location that minimizes uncertainty (maximizes information) about the stimulus. By comparing our model performance to human eye movement data and to predictions from a saliency and random model, we demonstrate that our model is best at predicting fixation locations. Modeling additional biological constraints will improve the prediction of fixation sequences. Our results suggest that information maximization is a useful principle for programming eye movements.

  15. Energy Band Calculations for Maximally Even Superlattices

    NASA Astrophysics Data System (ADS)

    Krantz, Richard; Byrd, Jason

    2007-03-01

    Superlattices are multiple-well, semiconductor heterostructures that can be described by one-dimensional potential wells separated by potential barriers. We refer to a distribution of wells and barriers based on the theory of maximally even sets as a maximally even superlattice. The prototypical example of a maximally even set is the distribution of white and black keys on a piano keyboard. Black keys may represent wells and the white keys represent barriers. As the number of wells and barriers increase, efficient and stable methods of calculation are necessary to study these structures. We have implemented a finite-element method using the discrete variable representation (FE-DVR) to calculate E versus k for these superlattices. Use of the FE-DVR method greatly reduces the amount of calculation necessary for the eigenvalue problem.

  16. Absence of parasympathetic reactivation after maximal exercise.

    PubMed

    de Oliveira, Tiago Peanha; de Alvarenga Mattos, Raphael; da Silva, Rhenan Bartels Ferreira; Rezende, Rafael Andrade; de Lima, Jorge Roberto Perrout

    2013-03-01

    The ability of the human organism to recover its autonomic balance soon after physical exercise cessation has an important impact on the individual's health status. Although the dynamics of heart rate recovery after maximal exercise has been studied, little is known about heart rate variability after this type of exercise. The aim of this study is to analyse the dynamics of heart rate and heart rate variability recovery after maximal exercise in healthy young men. Fifteen healthy male subjects (21734years; 24021kgm(-2) ) participated in the study. The experimental protocol consisted of an incremental maximal exercise test on a cycle ergometer, until maximal voluntary exhaustion. After the test, recovery R-R intervals were recorded for 5min. From the absolute differences between peak heart rate values and the heart rate values at 1 and 5min of the recovery, the heart rate recovery was calculated. Postexercise heart rate variability was analysed from calculations of the SDNN and RMSSD indexes, in 30-s windows (SDNN(30s) and RMSSD(30s) ) throughout recovery. One and 5min after maximal exercise cessation, the heart rate recovered 347 (66) and 755 (61) bpm, respectively. With regard to HRV recovery, while the SDNN(30s) index had a slight increase, RMSSD(30s) index remained totally suppressed throughout the recovery, suggesting an absence of vagal modulation reactivation and, possibly, a discrete sympathetic withdrawal. Therefore, it is possible that the main mechanism associated with the fall of HR after maximal exercise is sympathetic withdrawal or a vagal tone restoration without vagal modulation recovery. PMID:23383693

  17. Learning curves for mutual information maximization

    NASA Astrophysics Data System (ADS)

    Urbanczik, R.

    2003-07-01

    An unsupervised learning procedure based on maximizing the mutual information between the outputs of two networks receiving different but statistically dependent inputs is analyzed [S. Becker and G. Hinton, Nature (London) 355, 161 (1992)]. For a generic data model, I show that in the large sample limit the structure in the data is recognized by mutual information maximization. For a more restricted model, where the networks are similar to perceptrons, I calculate the learning curves for zero-temperature Gibbs learning. These show that convergence can be rather slow, and a way of regularizing the procedure is considered.

  18. A Reward-Maximizing Spiking Neuron as a Bounded Rational Decision Maker.

    PubMed

    Leibfried, Felix; Braun, Daniel A

    2015-08-01

    Rate distortion theory describes how to communicate relevant information most efficiently over a channel with limited capacity. One of the many applications of rate distortion theory is bounded rational decision making, where decision makers are modeled as information channels that transform sensory input into motor output under the constraint that their channel capacity is limited. Such a bounded rational decision maker can be thought to optimize an objective function that trades off the decision maker's utility or cumulative reward against the information processing cost measured by the mutual information between sensory input and motor output. In this study, we interpret a spiking neuron as a bounded rational decision maker that aims to maximize its expected reward under the computational constraint that the mutual information between the neuron's input and output is upper bounded. This abstract computational constraint translates into a penalization of the deviation between the neuron's instantaneous and average firing behavior. We derive a synaptic weight update rule for such a rate distortion optimizing neuron and show in simulations that the neuron efficiently extracts reward-relevant information from the input by trading off its synaptic strengths against the collected reward. PMID:26079747

  19. Teacher Expectancy Related to Student Performance in Vocational Education.

    ERIC Educational Resources Information Center

    Pandya, Himanshu S.

    A study was designed (1) to discover the effect of teacher expectation on student performance in the cognitive and in the psychomotor skills, and (2) to analyze students' attitudes toward teachers because of teacher expectations. The study utilized two different instructional units. The quality milk production unit was used to teach cognitive

  20. Expectancies vs. Background in the Prediction of Adult Drinking Patterns.

    ERIC Educational Resources Information Center

    Brown, Sandra A.

    Alcoholism research has independently focused on background characteristics and alcohol-related expectations, e.g., social and physical pleasure, reduced tension, and increased assertiveness, as important variables in identifying high risk individuals. To assess the utility of alcohol reinforcement expectations as predictors of drinking patterns,

  1. Understanding violations of Gricean maxims in preschoolers and adults

    PubMed Central

    Okanda, Mako; Asada, Kosuke; Moriguchi, Yusuke; Itakura, Shoji

    2015-01-01

    This study used a revised Conversational Violations Test to examine Gricean maxim violations in 4- to 6-year-old Japanese children and adults. Participants' understanding of the following maxims was assessed: be informative (first maxim of quantity), avoid redundancy (second maxim of quantity), be truthful (maxim of quality), be relevant (maxim of relation), avoid ambiguity (second maxim of manner), and be polite (maxim of politeness). Sensitivity to violations of Gricean maxims increased with age: 4-year-olds' understanding of maxims was near chance, 5-year-olds understood some maxims (first maxim of quantity and maxims of quality, relation, and manner), and 6-year-olds and adults understood all maxims. Preschoolers acquired the maxim of relation first and had the greatest difficulty understanding the second maxim of quantity. Children and adults differed in their comprehension of the maxim of politeness. The development of the pragmatic understanding of Gricean maxims and implications for the construction of developmental tasks from early childhood to adulthood are discussed. PMID:26191018

  2. Understanding violations of Gricean maxims in preschoolers and adults.

    PubMed

    Okanda, Mako; Asada, Kosuke; Moriguchi, Yusuke; Itakura, Shoji

    2015-01-01

    This study used a revised Conversational Violations Test to examine Gricean maxim violations in 4- to 6-year-old Japanese children and adults. Participants' understanding of the following maxims was assessed: be informative (first maxim of quantity), avoid redundancy (second maxim of quantity), be truthful (maxim of quality), be relevant (maxim of relation), avoid ambiguity (second maxim of manner), and be polite (maxim of politeness). Sensitivity to violations of Gricean maxims increased with age: 4-year-olds' understanding of maxims was near chance, 5-year-olds understood some maxims (first maxim of quantity and maxims of quality, relation, and manner), and 6-year-olds and adults understood all maxims. Preschoolers acquired the maxim of relation first and had the greatest difficulty understanding the second maxim of quantity. Children and adults differed in their comprehension of the maxim of politeness. The development of the pragmatic understanding of Gricean maxims and implications for the construction of developmental tasks from early childhood to adulthood are discussed. PMID:26191018

  3. Does evolution lead to maximizing behavior?

    PubMed

    Lehmann, Laurent; Alger, Ingela; Weibull, Jörgen

    2015-07-01

    A long-standing question in biology and economics is whether individual organisms evolve to behave as if they were striving to maximize some goal function. We here formalize this "as if" question in a patch-structured population in which individuals obtain material payoffs from (perhaps very complex multimove) social interactions. These material payoffs determine personal fitness and, ultimately, invasion fitness. We ask whether individuals in uninvadable population states will appear to be maximizing conventional goal functions (with population-structure coefficients exogenous to the individual's behavior), when what is really being maximized is invasion fitness at the genetic level. We reach two broad conclusions. First, no simple and general individual-centered goal function emerges from the analysis. This stems from the fact that invasion fitness is a gene-centered multigenerational measure of evolutionary success. Second, when selection is weak, all multigenerational effects of selection can be summarized in a neutral type-distribution quantifying identity-by-descent between individuals within patches. Individuals then behave as if they were striving to maximize a weighted sum of material payoffs (own and others). At an uninvadable state it is as if individuals would freely choose their actions and play a Nash equilibrium of a game with a goal function that combines self-interest (own material payoff), group interest (group material payoff if everyone does the same), and local rivalry (material payoff differences). PMID:26082379

  4. Maximal Controllability for Boundary Control Problems

    SciTech Connect

    Engel, Klaus-Jochen; Kramar Fijavz, Marjeta; Kloess, Bernd Nagel, Rainer; Sikolya, Eszter

    2010-10-15

    We develop a semigroup approach to abstract boundary control problems which allows to characterize the space of all approximately reachable states. We then introduce the 'maximal reachability space' giving an upper bound for this space. The abstract results are applied to the flow in a network controlled in a single vertex.

  5. Maximizing the Spectacle of Water Fountains

    ERIC Educational Resources Information Center

    Simoson, Andrew J.

    2009-01-01

    For a given initial speed of water from a spigot or jet, what angle of the jet will maximize the visual impact of the water spray in the fountain? This paper focuses on fountains whose spigots are arranged in circular fashion, and couches the measurement of the visual impact in terms of the surface area and the volume under the fountain's natural

  6. Ehrenfest's Lottery--Time and Entropy Maximization

    ERIC Educational Resources Information Center

    Ashbaugh, Henry S.

    2010-01-01

    Successful teaching of the Second Law of Thermodynamics suffers from limited simple examples linking equilibrium to entropy maximization. I describe a thought experiment connecting entropy to a lottery that mixes marbles amongst a collection of urns. This mixing obeys diffusion-like dynamics. Equilibrium is achieved when the marble distribution is…

  7. Faculty Salaries and the Maximization of Prestige

    ERIC Educational Resources Information Center

    Melguizo, Tatiana; Strober, Myra H.

    2007-01-01

    Through the lens of the emerging economic theory of higher education, we look at the relationship between salary and prestige. Starting from the premise that academic institutions seek to maximize prestige, we hypothesize that monetary rewards are higher for faculty activities that confer prestige. We use data from the 1999 National Study of

  8. Maximal dissipation in equations of evolution

    NASA Astrophysics Data System (ADS)

    Dafermos, C. M.

    The subject of this paper is evolutionary equations, such as the Hunter-Saxton equation or hyperbolic conservation laws, with the property that the initial value problem admits a multitude of solutions along which a certain "energy" functional decays at different rates. The aim is to examine whether solutions that dissipate the energy at maximal rate command special status.

  9. Ehrenfest's Lottery--Time and Entropy Maximization

    ERIC Educational Resources Information Center

    Ashbaugh, Henry S.

    2010-01-01

    Successful teaching of the Second Law of Thermodynamics suffers from limited simple examples linking equilibrium to entropy maximization. I describe a thought experiment connecting entropy to a lottery that mixes marbles amongst a collection of urns. This mixing obeys diffusion-like dynamics. Equilibrium is achieved when the marble distribution is

  10. How to Generate Good Profit Maximization Problems

    ERIC Educational Resources Information Center

    Davis, Lewis

    2014-01-01

    In this article, the author considers the merits of two classes of profit maximization problems: those involving perfectly competitive firms with quadratic and cubic cost functions. While relatively easy to develop and solve, problems based on quadratic cost functions are too simple to address a number of important issues, such as the use of

  11. Maximizing the Motivated Mind for Emergent Giftedness.

    ERIC Educational Resources Information Center

    Rea, Dan

    2001-01-01

    This article explains how the theory of the motivated mind conceptualizes the productive interaction of intelligence, creativity, and achievement motivation and how this theory can help educators to maximize students' emergent potential for giftedness. It discusses the integration of cold-order thinking and hot-chaotic thinking into fluid-adaptive

  12. Maximizing the Phytonutrient Content of Potatoes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We are exploring to what extent the rich genetic diversity of potatoes can be used to maximize the nutritional potential of potatoes. Metabolic profiling is being used to screen potatoes for genotypes with elevated amounts of vitamins and phytonutrients. Substantial differences in phytonutrients am...

  13. Faculty Salaries and the Maximization of Prestige

    ERIC Educational Resources Information Center

    Melguizo, Tatiana; Strober, Myra H.

    2007-01-01

    Through the lens of the emerging economic theory of higher education, we look at the relationship between salary and prestige. Starting from the premise that academic institutions seek to maximize prestige, we hypothesize that monetary rewards are higher for faculty activities that confer prestige. We use data from the 1999 National Study of…

  14. Maximal dinucleotide comma-free codes.

    PubMed

    Fimmel, Elena; Strngmann, Lutz

    2016-01-21

    The problem of retrieval and maintenance of the correct reading frame plays a significant role in RNA transcription. Circular codes, and especially comma-free codes, can help to understand the underlying mechanisms of error-detection in this process. In recent years much attention has been paid to the investigation of trinucleotide circular codes (see, for instance, Fimmel et al., 2014; Fimmel and Strngmann, 2015a; Michel and Pirillo, 2012; Michel et al., 2012, 2008), while dinucleotide codes had been touched on only marginally, even though dinucleotides are associated to important biological functions. Recently, all maximal dinucleotide circular codes were classified (Fimmel et al., 2015; Michel and Pirillo, 2013). The present paper studies maximal dinucleotide comma-free codes and their close connection to maximal dinucleotide circular codes. We give a construction principle for such codes and provide a graphical representation that allows them to be visualized geometrically. Moreover, we compare the results for dinucleotide codes with the corresponding situation for trinucleotide maximal self-complementary C(3)-codes. Finally, the results obtained are discussed with respect to Crick?s hypothesis about frame-shift-detecting codes without commas. PMID:26562635

  15. A Model of College Tuition Maximization

    ERIC Educational Resources Information Center

    Bosshardt, Donald I.; Lichtenstein, Larry; Zaporowski, Mark P.

    2009-01-01

    This paper develops a series of models for optimal tuition pricing for private colleges and universities. The university is assumed to be a profit maximizing, price discriminating monopolist. The enrollment decision of student's is stochastic in nature. The university offers an effective tuition rate, comprised of stipulated tuition less financial

  16. Maximizing Human Capital by Developing Multicultural Competence.

    ERIC Educational Resources Information Center

    Shaffer, Leigh S.

    1998-01-01

    Examines the growing demand for multicultural competence in college graduates, describes the course content and academic-advising activities recommended to develop it, and comments on the limits and inherent dangers of providing multicultural exposure universally. Academic advisors are urged to help students maximize their human capital by adding

  17. More Is Better: Maximizing Natural Learning Opportunities.

    ERIC Educational Resources Information Center

    Jung, Lee Ann

    2003-01-01

    This article discusses the increased emphasis on providing early intervention services within natural environments and how to maximize natural learning opportunities by using everyday activities that children experience and embedding intervention in daily routines. Guidelines for deciding the frequency of services, changing services, and the level

  18. Maximal rank of extremal marginal tracial states

    SciTech Connect

    Ohno, Hiromichi

    2010-09-15

    States on the coupled quantum system M{sub n}(C) x M{sub n}(C) whose restrictions to each subsystem are the normalized traces are called marginal tracial states. We investigate extremal marginal tracial states and compute their maximal rank. Diagonal marginal tracial states are also considered.

  19. The evolution of utility functions and psychological altruism.

    PubMed

    Clavien, Christine; Chapuisat, Michel

    2016-04-01

    Numerous studies show that humans tend to be more cooperative than expected given the assumption that they are rational maximizers of personal gain. As a result, theoreticians have proposed elaborated formal representations of human decision-making, in which utility functions including "altruistic" or "moral" preferences replace the purely self-oriented "Homo economicus" function. Here we review mathematical approaches that provide insights into the mathematical stability of alternative utility functions. Candidate utility functions may be evaluated with help of game theory, classical modeling of social evolution that focuses on behavioral strategies, and modeling of social evolution that focuses directly on utility functions. We present the advantages of the latter form of investigation and discuss one surprisingly precise result: "Homo economicus" as well as "altruistic" utility functions are less stable than a function containing a preference for the common welfare that is only expressed in social contexts composed of individuals with similar preferences. We discuss the contribution of mathematical models to our understanding of human other-oriented behavior, with a focus on the classical debate over psychological altruism. We conclude that human can be psychologically altruistic, but that psychological altruism evolved because it was generally expressed towards individuals that contributed to the actor's fitness, such as own children, romantic partners and long term reciprocators. PMID:26598465

  20. Expectancy in Rapid Decision Making.

    ERIC Educational Resources Information Center

    Hinrichs, James V.

    This paper briefly reviews how subjects enhance performance by favoring some stimuli over others. The author calls the mechanism by which this is achieved "expectancy", a generic term including preparatory set, behavioral hypotheses, orienting reflex, and anticipatory goal responses. Temporal and event expectancy are contrasted. Verbal prediction

  1. Sibling Status Effects: Adult Expectations.

    ERIC Educational Resources Information Center

    Baskett, Linda Musun

    1985-01-01

    This study attempted to determine what expectations or beliefs adults might hold about a child based on his or her sibling status alone. Ratings on 50 adjective pairs for each of three sibling status types, only, oldest, and youngest child, were assessed in relation to adult expectations, birth order, and parental status of rater. (Author/DST)

  2. Institutional Differences: Expectations and Perceptions.

    ERIC Educational Resources Information Center

    Silver, Harold

    1982-01-01

    The history of higher education has paid scant attention to the attitudes and expectations of its customers, students, and employers of graduates. Recent research on student and employer attitudes toward higher education sectors has not taken into account these expectations in the context of recent higher education history. (Author/MSE)

  3. Labview utilities

    Energy Science and Technology Software Center (ESTSC)

    2011-09-30

    The software package provides several utilities written in LabView. These utilities don't form independent programs, but rather can be used as a library or controls in other labview programs. The utilities include several new controls (xcontrols), VIs for input and output routines, as well as other 'helper'-functions not provided in the standard LabView environment.

  4. The price of anarchy is maximized at the percolation threshold

    NASA Astrophysics Data System (ADS)

    Skinner, Brian

    2015-03-01

    When many independent users try to route traffic through a network, the flow can easily become suboptimal as a consequence of congestion of the most efficient paths. The degree of this suboptimality is quantified by the so-called ``price of anarchy'' (POA), but so far there are no general rules for when to expect a large POA in a random network. Here I address this question by introducing a simple model of flow through a network with randomly-placed ``congestible'' and ``incongestible'' links. I show that the POA is maximized precisely when the fraction of congestible links matches the percolation threshold of the lattice. Both the POA and the total cost demonstrate critical scaling near the percolation threshold.

  5. Price of anarchy is maximized at the percolation threshold.

    PubMed

    Skinner, Brian

    2015-05-01

    When many independent users try to route traffic through a network, the flow can easily become suboptimal as a consequence of congestion of the most efficient paths. The degree of this suboptimality is quantified by the so-called price of anarchy (POA), but so far there are no general rules for when to expect a large POA in a random network. Here I address this question by introducing a simple model of flow through a network with randomly placed congestible and incongestible links. I show that the POA is maximized precisely when the fraction of congestible links matches the percolation threshold of the lattice. Both the POA and the total cost demonstrate critical scaling near the percolation threshold. PMID:26066138

  6. Price of anarchy is maximized at the percolation threshold

    NASA Astrophysics Data System (ADS)

    Skinner, Brian

    2015-05-01

    When many independent users try to route traffic through a network, the flow can easily become suboptimal as a consequence of congestion of the most efficient paths. The degree of this suboptimality is quantified by the so-called price of anarchy (POA), but so far there are no general rules for when to expect a large POA in a random network. Here I address this question by introducing a simple model of flow through a network with randomly placed congestible and incongestible links. I show that the POA is maximized precisely when the fraction of congestible links matches the percolation threshold of the lattice. Both the POA and the total cost demonstrate critical scaling near the percolation threshold.

  7. Experimental implementation of maximally synchronizable networks

    NASA Astrophysics Data System (ADS)

    Sevilla-Escoboza, R.; Buldú, J. M.; Boccaletti, S.; Papo, D.; Hwang, D.-U.; Huerta-Cuellar, G.; Gutiérrez, R.

    2016-04-01

    Maximally synchronizable networks (MSNs) are acyclic directed networks that maximize synchronizability. In this paper, we investigate the feasibility of transforming networks of coupled oscillators into their corresponding MSNs. By tuning the weights of any given network so as to reach the lowest possible eigenratio λN /λ2, the synchronized state is guaranteed to be maintained across the longest possible range of coupling strengths. We check the robustness of the resulting MSNs with an experimental implementation of a network of nonlinear electronic oscillators and study the propagation of the synchronization errors through the network. Importantly, a method to study the effects of topological uncertainties on the synchronizability is proposed and explored both theoretically and experimentally.

  8. Hamiltonian formalism and path entropy maximization

    NASA Astrophysics Data System (ADS)

    Davis, Sergio; González, Diego

    2015-10-01

    Maximization of the path information entropy is a clear prescription for constructing models in non-equilibrium statistical mechanics. Here it is shown that, following this prescription under the assumption of arbitrary instantaneous constraints on position and velocity, a Lagrangian emerges which determines the most probable trajectory. Deviations from the probability maximum can be consistently described as slices in time by a Hamiltonian, according to a nonlinear Langevin equation and its associated Fokker-Planck equation. The connections unveiled between the maximization of path entropy and the Langevin/Fokker-Planck equations imply that missing information about the phase space coordinate never decreases in time, a purely information-theoretical version of the second law of thermodynamics. All of these results are independent of any physical assumptions, and thus valid for any generalized coordinate as a function of time, or any other parameter. This reinforces the view that the second law is a fundamental property of plausible inference.

  9. [Chemical constituents of Trichosanthes kirilowii Maxim].

    PubMed

    Sun, Xiao-Ye; Wu, Hong-Hua; Fu, Ai-Zhen; Zhang, Peng

    2012-07-01

    To study the chemical constituents of Trichosanthes kirilowii Maxim., chromatographic methods such as D101 macroporous resin, silica gel column chromatographic technology, Sephadex LH-20, octadecylsilyl (ODS) column chromatographic technique and preparative HPLC were used and nine compounds were isolated from a 95% (v/v) ethanol extract of the plant. By using spectroscopic techniques including 1H NMR, 13C NMR, 1H-1H COSY, HSQC and HMBC, these compounds were identified as 5-ethoxymethyl-1-carboxyl propyl-1H-pyrrole-2-carbaldehyde (1), 5-hydroxymethyl-2-furfural (2), chrysoeriol (3), 4'-hydroxyscutellarin (4), vanillic acid (5), alpha-spinasterol (6), beta-D-glucopyranosyl-a-spinasterol (7), stigmast-7-en-3beta-ol (8), and adenosine (9), separately. Among them, compound 1 is a new compound, and compounds 3, 4 and 5 are isolated from the genus Trichosanthes kirilowii Maxim. for the first time. PMID:22993858

  10. Maximizing the bandgap of BCN nanoribbons

    NASA Astrophysics Data System (ADS)

    Baldez, Raisi; Piquini, Paulo; Schmidt, Alex; Kuroda, Marcelo

    2015-03-01

    Carbon and boron-nitride based compounds share many electronic and structural features. This fact permits mixed carbon-boron-nitride compounds to be easily synthesized without significant structural changes. Further, the partially ionic character of the boron-nitrogen bonds allow to modify the electronics of carbon based materials, introducing a variability that can be used to tune the electronic properties according to the boron and nitrogen contents. Graphene and graphene nanoribbons have emerged as promising materials for electronic applications, due to the high mobility of its charge carriers. In this work we use the genetic algorithm approach to search for configurations with variable B, C and N contents that maximize the band gap of BxCyNz nanoribbons. Different stoichiometries are analyzed and the structural patterns that lead to the maximal band gaps are presented.

  11. Consistent 4-form fluxes for maximal supergravity

    NASA Astrophysics Data System (ADS)

    Godazgar, Hadi; Godazgar, Mahdi; Krger, Olaf; Nicolai, Hermann

    2015-10-01

    We derive new anstze for the 4-form field strength of D = 11 supergravity corresponding to uplifts of four-dimensional maximal gauged supergravity. In particular, the anstze directly yield the components of the 4-form field strength in terms of the scalars and vectors of the four-dimensional maximal gauged supergravity in this way they provide an explicit uplift of all four-dimensional consistent truncations of D = 11 supergravity. The new anstze provide a substantially simpler method for uplifting d = 4 flows compared to the previously available method using the 3-form and 6-form potential anstze. The ansatz for the Freund-Rubin term allows us to conjecture a `master formula' for the latter in terms of the scalar potential of d = 4 gauged supergravity and its first derivative. We also resolve a long-standing puzzle concerning the antisymmetry of the flux obtained from uplift anstze.

  12. Osteoblastic proliferative activity of Epimedium brevicornum Maxim.

    PubMed

    Meng, F H; Li, Y B; Xiong, Z L; Jiang, Z M; Li, F M

    2005-03-01

    The effect of the extracts of Epimedium brevicornum Maxim. was investigated on proliferative activity in vitro. The osteoblast-like UMR106 cells was employed as an osteoblast model. The EtOH extract and the n-butanol fraction from the crude extract were found to show proliferation stimulating activity. Three flavonoid compounds (icariin, epimedin B and epimedin C) were isolated from this fraction by activity-guided assay, and the effects on cell proliferation were studied. Icariin produced the most significant promoting effect on the proliferation in osteoblast-like UMR106 cells. The results suggested that E. brevicornum Maxim. extracts might have potential activity against osteoporosis, and flavonoids such as icariin might be the active constituents stimulating osteoblasts. PMID:15830840

  13. Statistical mechanics of mutual information maximization

    NASA Astrophysics Data System (ADS)

    Urbanczik, R.

    2000-03-01

    An unsupervised learning procedure based on maximizing the mutual information between the outputs of two networks receiving different but statistically dependent inputs is analyzed (Becker S. and Hinton G., Nature, 355 (1992) 161). By exploiting a formal analogy to supervised learning in parity machines, the theory of zero-temperature Gibbs learning for the unsupervised procedure is presented for the case that the networks are perceptrons and for the case of fully connected committees.

  14. Beyond "utilitarianism": maximizing the clinical impact of moral judgment research.

    PubMed

    Rosas, Alejandro; Koenigs, Michael

    2014-01-01

    The use of hypothetical moral dilemmas--which pit utilitarian considerations of welfare maximization against emotionally aversive "personal" harms--has become a widespread approach for studying the neuropsychological correlates of moral judgment in healthy subjects, as well as in clinical populations with social, cognitive, and affective deficits. In this article, we propose that a refinement of the standard stimulus set could provide an opportunity to more precisely identify the psychological factors underlying performance on this task, and thereby enhance the utility of this paradigm for clinical research. To test this proposal, we performed a re-analysis of previously published moral judgment data from two clinical populations: neurological patients with prefrontal brain damage and psychopathic criminals. The results provide intriguing preliminary support for further development of this assessment paradigm. PMID:25010445

  15. Uplink Array Calibration via Far-Field Power Maximization

    NASA Technical Reports Server (NTRS)

    Vilnrotter, V.; Mukai, R.; Lee, D.

    2006-01-01

    Uplink antenna arrays have the potential to greatly increase the Deep Space Network s high-data-rate uplink capabilities as well as useful range, and to provide additional uplink signal power during critical spacecraft emergencies. While techniques for calibrating an array of receive antennas have been addressed previously, proven concepts for uplink array calibration have yet to be demonstrated. This article describes a method of utilizing the Moon as a natural far-field reflector for calibrating a phased array of uplink antennas. Using this calibration technique, the radio frequency carriers transmitted by each antenna of the array are optimally phased to ensure that the uplink power received by the spacecraft is maximized.

  16. Maximize crude unit No. 2 oil yield design and operation

    SciTech Connect

    Sloley, A.W.

    1997-05-01

    Recent refinery industry trends are to optimize crude unit operation with advanced control technology such as real-time-optimization. One potential crude unit optimization objective could be maximizing diesel product yields and minimizing the quantity of diesel boiling range material in the FCC feed. Appropriately designed advanced process control technology for a crude unit can be used to fully utilize existing equipment performance. The advanced process control scheme (or operator) can adjust the appropriate process variables to optimize the diesel yields against the current unit limitations. Process and equipment design changes may nevertheless be required to fully implement the diesel product optimization, depending on the crude unit equipment limitations. Therefore, crude unit process variable optimization and potential equipment design issues should be carefully addressed. While each refinery crude unit`s design, operation and equipment constraints are different, the fundamental operating variables and the process and equipment design issues are common to all crude units.

  17. Patient expectations of dental services. Image affects expectations, and expectations affect perceived service quality.

    PubMed

    Clow, K E; Fischer, A K; O'Bryan, D

    1995-01-01

    The authors construct a theoretical model of the antecedents of expectations for dental services by analyzing survey responses from 240 dental patients. The patients' image of the dentist, tangible cues, situational factors, and patient satisfaction with prior service encounters have the greatest influence on expectations of service, whereas marketing variables, such as price and advertising, appear to have no effect. PMID:10152791

  18. Externalities, expectations, and Pigouvian taxes

    SciTech Connect

    Cornes, R.; Sandler, T.

    1985-03-01

    This article derives Pigouvian-type corrective measures for reciprocal externalities when non-Nash behavior characterizes the participants. These reciprocal externalities may involve various kinds of environmental pollutants, such as acid rain. A comparison between corrective measures for Nash and non-Nash behavior demonstrates that positive conjectures, regarding the other agent's externality-generating activity, have an expectation-internalizing influence that usually reduces the required corrective measures. Negative conjectures (e.g., free-riding expectations), however, have an expectation-externalizing effect that increases the required corrective measures. The article analyzes both two-person and n-person externalities. 13 references, 3 figures, 1 table.

  19. Physical activity extends life expectancy

    Cancer.gov

    Leisure-time physical activity is associated with longer life expectancy, even at relatively low levels of activity and regardless of body weight, according to a study by a team of researchers led by the NCI.

  20. Utility Static Generation Reliability

    Energy Science and Technology Software Center (ESTSC)

    1993-03-05

    PICES (Probabilistic Investigation of Capacity and Energy Shortages) was developed for estimating an electric utility''s expected frequency and duration of capacity deficiencies on a daily on and off-peak basis. In addition to the system loss-of-load probability (LOLP) and loss-of-load expectation (LOLE) indices, PICES calculates the expected frequency and duration of system capacity deficiencies and the probability, expectation, and expected frequency and duration of a range of system reserve margin states. Results are aggregated and printedmore »on a weekly, monthly, or annual basis. The program employs hourly load data and either the two-state (on/off) or a more sophisticated three-state (on/partially on/fully off) generating unit representation. Unit maintenance schedules are determined on a weekly, levelized reserve margin basis. In addition to the 8760-hour annual load record, the user provides the following information for each unit: plant capacity, annual maintenance requirement, two or three-state unit failure and repair rates, and for three-state models, the partial state capacity deficiency. PICES can also supply default failure and repair rate values, based on the Edison Electric Institute''s 1979 Report on Equipment Availability for the Ten-Year Period 1968 Through 1977, for many common plant types. Multi-year analysis can be performed by specifying as input data the annual peak load growth rates and plant addition and retirement schedules for each year in the study.« less

  1. Expectation and the tilt aftereffect.

    PubMed

    Pinchuk-Yacobi, Noga; Dekel, Ron; Sagi, Dov

    2015-09-01

    Exposure to oriented stimuli leads to a bias in the perceived orientation of subsequently viewed stimuli (tilt aftereffect, TAE). This is traditionally attributed to sensory adaptation, and viewed as a stimulus-driven process, independent of stimulus predictability. Here, we tested whether the magnitude of the TAE is modulated by expectations, and specifically, whether TAE depends on the congruency of adapted and expected orientations. Observers were presented at fixation with successive pairs of oriented Gabor patches (s=0.6, l=0.3). Each Gabor was presented for 50ms with 600ms interval between pair members (pairs were separated by 1-1.5secs). Gabor pairs were arranged in blocks, forming two experimental conditions with orientation either expected or not expected. For all blocks, the orientation of the first Gabor in each pair was randomized (20 relative to vertical). In the 'expected' condition, the orientation of the second Gabor correlated, either positively or negatively, in different sessions, with that of the first Gabor. In the 'not-expected' condition, the orientation of the second Gabor was independent of the first Gabor (randomized 20). Intermixed test trials (33%) were used to measure the shift in subjects' perceived vertical, with the second pair member serving as a target, oriented around the vertical, permitting a measurement of the TAE produced by the presentation of the first Gabor member. Presentation of the oriented Gabors led to a tilt aftereffect, which was modulated by the expected orientation. The aftereffect was significantly higher (N=5; p< 0.01, pairwise t-test) in the positively correlated blocks (1.60.2SE) than in the corresponding 'not expected' blocks (1.00.3SE). In the negatively correlated blocks (N=2), the aftereffect was lower (0.61.1SE) than in the corresponding 'not expected' blocks (1.00.7SE). These findings indicate a role of expectation in generating the perceptual tilt aftereffect and are in line with predictive coding models of perception. Acknowledgement: BRF/ISF. Meeting abstract presented at VSS 2015. PMID:26325727

  2. Caffeinated Alcohol Use and Expectancies for Caffeine Versus Alcohol

    PubMed Central

    Lau-Barraco, Cathy; Linden, Ashley N.

    2014-01-01

    Background Caffeinated alcoholic beverage (CAB) use is related to alcohol-related risk. Limited research has examined outcome expectancies and CAB consumption. Objectives This study tested the predictive utility of caffeine and alcohol expectancies in CAB use outcomes (i.e. quantity, frequency, and alcohol-related harms). Methods Participants were 419 (302 women) alcohol and caffeine users from a mid-sized urban university. Data collection occurred between August 2010 and December 2011. Participants completed measures of caffeine and alcohol expectancies, alcohol problems, alcohol use, and CAB use. Results Caffeine and alcohol expectancies contributed uniquely to approximately 12% of the variability in quantity, 8% in frequency, and 16% in problems. When examined separately, alcohol expectancies explained approximately 10% to 11% of the variance, whereas caffeine expectancies accounted for 6% of the variance in CAB use quantity. For CAB use frequency, alcohol and caffeine expectancies accounted for about 8% and 4%, respectively. Alcohol expectancies accounted for 12% to 14% of variance, whereas caffeine expectancies accounted for 4% to 6% in alcohol-related harms. Conclusions/Importance The present study sought to address a gap in the literature regarding the contributions of expectancies in the prediction of CAB use. Our findings provide support for the predictive utility of both caffeine and alcohol expectancies in accounting for individual variability in CAB use but alcohol expectancies may exert greater impact on use patterns. Inclusion of both types of expectancies in larger theoretical frameworks may be beneficial in gaining a more complete and deeper conceptualization of this risky behavior. PMID:24708428

  3. Techniques and technologies to maximize mucosal exposure.

    PubMed

    Moons, Leon M G; Gralnek, Ian M; Siersema, Peter D

    2015-04-01

    Performing high-quality colonoscopy is one of the important goals of gastroenterology practices and requires achieving a high level of bowel cleansing, performing good and safe polypectomy, and detecting all polyps present in the colon. This article summarizes currently available techniques and technologies to maximize mucosal visualization. Several maneuvers can be applied during insertion and withdrawal of the colonoscope to optimize mucosal visualization and decrease the number of missed polyps. Newly developed technologies support the endoscopist in the detection of polyps. Each technique is reviewed, with emphasis on the impact on colorectal polyp detection. PMID:25839682

  4. Electromagnetically induced grating with maximal atomic coherence

    SciTech Connect

    Carvalho, Silvania A.; Araujo, Luis E. E. de

    2011-10-15

    We describe theoretically an atomic diffraction grating that combines an electromagnetically induced grating with a coherence grating in a double-{Lambda} atomic system. With the atom in a condition of maximal coherence between its lower levels, the combined gratings simultaneously diffract both the incident probe beam as well as the signal beam generated through four-wave mixing. A special feature of the atomic grating is that it will diffract any beam resonantly tuned to any excited state of the atom accessible by a dipole transition from its ground state.

  5. Multipartite maximally entangled states in symmetric scenarios

    NASA Astrophysics Data System (ADS)

    Gonzlez-Guilln, Carlos E.

    2012-08-01

    We consider the class of (N+1)-partite states suitable for protocols where there is a powerful party, the authority, and the other N parties play the same role, namely, the state of their system lies in the symmetric Hilbert space. We show that, within this scenario, there is a maximally entangled state that can be transform by a local operations and classical communication protocol into any other state. In addition, we show how to use the protocol efficiently, including the construction of the state, and discuss security issues for possible applications to cryptographic protocols. As an immediate consequence we recover a sequential protocol that implements the 1-to-N symmetric cloning.

  6. Effect of fatigue on maximal velocity and maximal torque during short exhausting cycling.

    PubMed

    Buttelli, O; Seck, D; Vandewalle, H; Jouanin, J C; Monod, H

    1996-01-01

    A group of 24 subjects performed on a cycle ergometer a fatigue test consisting of four successive all-out sprints against the same braking torque. The subjects were not allowed time to recover between sprints and consequently the test duration was shorter than 30 s. The pedal velocity was recorded every 10 ms from a disc fixed to the flywheel with 360 slots passing in front of a photo-electric cell linked to a microcomputer which processed the data. Taking into account the variation of kinetic energy of the ergometer flywheel, it was possible to determine the linear torque velocity relationship from data obtained during the all-out cycling exercise by computing torque and velocity from zero velocity to peak velocity according to a method proposed previously. The maximal theoretical velocity (v(0)) and the maximal theoretical torque (T(0)) were estimated by extrapolation of each torque-velocity relationship. Maximal power (P(max)) was calculated from the values of T(0) and v(0) (P(max) = 0.25v(0)T(0). The kinetics of v(0), T(0) and P(max) was assumed to express the effects of fatigue on the muscle contractile properties (maximal shortening velocity, maximal muscle strength and maximal power). Fatigue induced a parallel shift to the left of the torque-velocity relationships. The v( 0), T(0) and P(max) decreases were equal to 16.3 percent, 17.3 percent and 31 percent, respectively. The magnitude of the decrease was similar for v(0) and T(0) which suggested that P max decreased because of a slowing of maximal shortening velocity as well as a loss in maximal muscle strength. However, the interpretation of a decrease in cycling v(0) which has the dimension of a maximal cycling frequency is made difficult by the possible interactions between the agonistic and the antagonistic muscles and could also be explained by a slowing of the muscle relaxation rate. PMID:8861688

  7. Maximizing strain in miniaturized dielectric elastomer actuators

    NASA Astrophysics Data System (ADS)

    Rosset, Samuel; Araromi, Oluwaseun; Shea, Herbert

    2015-04-01

    We present a theoretical model to optimise the unidirectional motion of a rigid object bonded to a miniaturized dielectric elastomer actuator (DEA), a configuration found for example in AMI's haptic feedback devices, or in our tuneable RF phase shifter. Recent work has shown that unidirectional motion is maximized when the membrane is both anistropically prestretched and subjected to a dead load in the direction of actuation. However, the use of dead weights for miniaturized devices is clearly highly impractical. Consequently smaller devices use the membrane itself to generate the opposing force. Since the membrane covers the entire frame, one has the same prestretch condition in the active (actuated) and passive zones. Because the passive zone contracts when the active zone expands, it does not provide a constant restoring force, reducing the maximum achievable actuation strain. We have determined the optimal ratio between the size of the electrode (active zone) and the passive zone, as well as the optimal prestretch in both in-plane directions, in order to maximize the absolute displacement of the rigid object placed at the active/passive border. Our model and experiments show that the ideal active ratio is 50%, with a displacement twice smaller than what can be obtained with a dead load. We expand our fabrication process to also show how DEAs can be laser-post-processed to remove carefully chosen regions of the passive elastomer membrane, thereby increasing the actuation strain of the device.

  8. Maximal lactate steady state in Judo

    PubMed Central

    de Azevedo, Paulo Henrique Silva Marques; Pithon-Curi, Tania; Zagatto, Alessandro Moura; Oliveira, João; Perez, Sérgio

    2014-01-01

    Summary Background: the purpose of this study was to verify the validity of respiratory compensation threshold (RCT) measured during a new single judo specific incremental test (JSIT) for aerobic demand evaluation. Methods: to test the validity of the new test, the JSIT was compared with Maximal Lactate Steady State (MLSS), which is the gold standard procedure for aerobic demand measuring. Eight well-trained male competitive judo players (24.3 ± 7.9 years; height of 169.3 ± 6.7cm; fat mass of 12.7 ± 3.9%) performed a maximal incremental specific test for judo to assess the RCT and performed on 30-minute MLSS test, where both tests were performed mimicking the UchiKomi drills. Results: the intensity at RCT measured on JSIT was not significantly different compared to MLSS (p=0.40). In addition, it was observed high and significant correlation between MLSS and RCT (r=0.90, p=0.002), as well as a high agreement. Conclusions: RCT measured during JSIT is a valid procedure to measure the aerobic demand, respecting the ecological validity of Judo. PMID:25332923

  9. Spiders Tune Glue Viscosity to Maximize Adhesion.

    PubMed

    Amarpuri, Gaurav; Zhang, Ci; Diaz, Candido; Opell, Brent D; Blackledge, Todd A; Dhinojwala, Ali

    2015-11-24

    Adhesion in humid conditions is a fundamental challenge to both natural and synthetic adhesives. Yet, glue from most spider species becomes stickier as humidity increases. We find the adhesion of spider glue, from five diverse spider species, maximizes at very different humidities that matches their foraging habitats. By using high-speed imaging and spreading power law, we find that the glue viscosity varies over 5 orders of magnitude with humidity for each species, yet the viscosity at maximal adhesion for each species is nearly identical, 10(5)-10(6) cP. Many natural systems take advantage of viscosity to improve functional response, but spider glue's humidity responsiveness is a novel adaptation that makes the glue stickiest in each species' preferred habitat. This tuning is achieved by a combination of proteins and hygroscopic organic salts that determines water uptake in the glue. We therefore anticipate that manipulation of polymer-salts interaction to control viscosity can provide a simple mechanism to design humidity responsive smart adhesives. PMID:26513350

  10. Optimizing Population Variability to Maximize Benefit

    PubMed Central

    Izu, Leighton T.; Bányász, Tamás; Chen-Izu, Ye

    2015-01-01

    Variability is inherent in any population, regardless whether the population comprises humans, plants, biological cells, or manufactured parts. Is the variability beneficial, detrimental, or inconsequential? This question is of fundamental importance in manufacturing, agriculture, and bioengineering. This question has no simple categorical answer because research shows that variability in a population can have both beneficial and detrimental effects. Here we ask whether there is a certain level of variability that can maximize benefit to the population as a whole. We answer this question by using a model composed of a population of individuals who independently make binary decisions; individuals vary in making a yes or no decision, and the aggregated effect of these decisions on the population is quantified by a benefit function (e.g. accuracy of the measurement using binary rulers, aggregate income of a town of farmers). Here we show that an optimal variance exists for maximizing the population benefit function; this optimal variance quantifies what is often called the “right mix” of individuals in a population. PMID:26650247

  11. Predicting maximal strength in trained postmenopausal woman.

    PubMed

    Kemmler, Wolfgang K; Lauber, Dirk; Wassermann, Alfred; Mayhew, Jerry L

    2006-11-01

    The purpose of this study was to present an equation that accurately predicts 1 repetition maximum (RM) over a wide range of repetitions to fatigue (RTF) for 4 different machine resistance exercises in postmenopausal women. Seventy trained women (age = 57.4 +/- 3.1 years) performed maximal and submaximal repetitions on leg press, bench press, rowing, and leg adduction machines at the conclusion of a 2-year training program. Maximal repetitions were performed on each exercise in the following ranges: 3-5RM, 6-10RM, 11-15RM, and 16-20RM. Special regard was taken to maintain the identical execution of each test (i.e., range of motion, starting angle, speed of movement). One cubic polynomial (w(i) [0.988-0.0000584 r(i)(3) + 0.00190 r(i)(2) + 0.0104 r(i),] where w(i) is the load of measurement I, and r(i) is the number of repetitions) accurately predicted 1RM from RTF with mean absolute differences between actual 1RM and predicted 1RM for the 4 exercises of 1.5-3.1% and with coefficients of variation of <3.3%. Equation accuracy was independent of the exercise type or the number of RTF. Thus, this study supported the validity of RTF to adequately estimate 1RM over a wide range of repetitions and within different exercises in trained, older female subjects. PMID:17194251

  12. TRENDS IN SENESCENT LIFE EXPECTANCY

    PubMed Central

    Bongaarts, John

    2009-01-01

    The distinction between senescent and non-senescent mortality proves to be very valuable for describing and analyzing age patterns of death rates. Unfortunately, standard methods for estimating these mortality components are lacking. The first part of this study discusses alternative methods for estimating background and senescent mortality among adults and proposes a simple approach based on death rates by causes of death. The second part examines trends in senescent life expectancy (i.e. the life expectancy implied by senescent mortality) and compares them with trends in conventional longevity indicators between 1960 and 2000 in a group of 17 developed countries with low mortality. Senescent life expectancy for females rises at an average rate of 1.54 years per decade between 1960 and 2000 in these countries. The shape of the distribution of senescent deaths by age remains relatively invariant while the entire distribution shifts over time to higher ages as longevity rose. PMID:19851933

  13. The asymptotic equipartition property in reinforcement learning and its relation to return maximization.

    PubMed

    Iwata, Kazunori; Ikeda, Kazushi; Sakai, Hideaki

    2006-01-01

    We discuss an important property called the asymptotic equipartition property on empirical sequences in reinforcement learning. This states that the typical set of empirical sequences has probability nearly one, that all elements in the typical set are nearly equi-probable, and that the number of elements in the typical set is an exponential function of the sum of conditional entropies if the number of time steps is sufficiently large. The sum is referred to as stochastic complexity. Using the property we elucidate the fact that the return maximization depends on two factors, the stochastic complexity and a quantity depending on the parameters of environment. Here, the return maximization means that the best sequences in terms of expected return have probability one. We also examine the sensitivity of stochastic complexity, which is a qualitative guide in tuning the parameters of action-selection strategy, and show a sufficient condition for return maximization in probability. PMID:16202563

  14. Excap: maximization of haplotypic diversity of linked markers.

    PubMed

    Kahles, André; Sarqume, Fahad; Savolainen, Peter; Arvestad, Lars

    2013-01-01

    Genetic markers, defined as variable regions of DNA, can be utilized for distinguishing individuals or populations. As long as markers are independent, it is easy to combine the information they provide. For nonrecombinant sequences like mtDNA, choosing the right set of markers for forensic applications can be difficult and requires careful consideration. In particular, one wants to maximize the utility of the markers. Until now, this has mainly been done by hand. We propose an algorithm that finds the most informative subset of a set of markers. The algorithm uses a depth first search combined with a branch-and-bound approach. Since the worst case complexity is exponential, we also propose some data-reduction techniques and a heuristic. We implemented the algorithm and applied it to two forensic caseworks using mitochondrial DNA, which resulted in marker sets with significantly improved haplotypic diversity compared to previous suggestions. Additionally, we evaluated the quality of the estimation with an artificial dataset of mtDNA. The heuristic is shown to provide extensive speedup at little cost in accuracy. PMID:24244403

  15. Paracrine communication maximizes cellular response fidelity in wound signaling

    PubMed Central

    Handly, L Naomi; Pilko, Anna; Wollman, Roy

    2015-01-01

    Population averaging due to paracrine communication can arbitrarily reduce cellular response variability. Yet, variability is ubiquitously observed, suggesting limits to paracrine averaging. It remains unclear whether and how biological systems may be affected by such limits of paracrine signaling. To address this question, we quantify the signal and noise of Ca2+ and ERK spatial gradients in response to an in vitro wound within a novel microfluidics-based device. We find that while paracrine communication reduces gradient noise, it also reduces the gradient magnitude. Accordingly we predict the existence of a maximum gradient signal to noise ratio. Direct in vitro measurement of paracrine communication verifies these predictions and reveals that cells utilize optimal levels of paracrine signaling to maximize the accuracy of gradient-based positional information. Our results demonstrate the limits of population averaging and show the inherent tradeoff in utilizing paracrine communication to regulate cellular response fidelity. DOI: http://dx.doi.org/10.7554/eLife.09652.001 PMID:26448485

  16. Excap: Maximization of Haplotypic Diversity of Linked Markers

    PubMed Central

    Kahles, Andr; Sarqume, Fahad; Savolainen, Peter; Arvestad, Lars

    2013-01-01

    Genetic markers, defined as variable regions of DNA, can be utilized for distinguishing individuals or populations. As long as markers are independent, it is easy to combine the information they provide. For nonrecombinant sequences like mtDNA, choosing the right set of markers for forensic applications can be difficult and requires careful consideration. In particular, one wants to maximize the utility of the markers. Until now, this has mainly been done by hand. We propose an algorithm that finds the most informative subset of a set of markers. The algorithm uses a depth first search combined with a branch-and-bound approach. Since the worst case complexity is exponential, we also propose some data-reduction techniques and a heuristic. We implemented the algorithm and applied it to two forensic caseworks using mitochondrial DNA, which resulted in marker sets with significantly improved haplotypic diversity compared to previous suggestions. Additionally, we evaluated the quality of the estimation with an artificial dataset of mtDNA. The heuristic is shown to provide extensive speedup at little cost in accuracy. PMID:24244403

  17. Utility diversification

    SciTech Connect

    Kahn, A.E.

    1982-01-01

    A review of the available evidence of the effect of diversification on a utility's financial attractiveness suggests that diversified gas companies have higher earnings, better credit ratings, and more marketable securities than do the less diversified utilities. Regulatory commissions must, however, always be alert to ways in which a company's unregulated activities might adversely affect consumers of the regulated service. Once assured that the service customers are adequately protected, the commission should neither review the specific ventures of unregulated subsidiaries nor become involved in regulating their security issuances or dividend payments. In general, utility diversification should be subject only to managerial discretion and the discipline of the market.

  18. Utility diversification

    SciTech Connect

    Kahn, A.E.

    1983-01-01

    A review of the available evidence of the effect of diversification on a utility's financial attractiveness suggests that diversified gas companies have higher earnings, better credit ratings, and more marketable securities than do the less diversified utilities. Regulatory commissions must, however, always be alert to ways in which a company's unregulated activities might adversely affect recipients of the regulated service. Once assured that the service customers are adequately protected, the commission should neither review the specific ventures of unregulated subsidiaries nor become involved in regulating their security issuances or dividend payments. In general, utility diversification should be subject only to managerial discretion and the discipline of the market.

  19. Great Expectations and New Beginnings

    ERIC Educational Resources Information Center

    Davis, Frances A.

    2009-01-01

    Great Expectation and New Beginnings is a prenatal family support program run by the Family, Infant, and Preschool Program (FIPP) in North Carolina. FIPP has developed an evidence-based integrated framework of early childhood intervention and family support that includes three primary components: providing intervention in everyday family

  20. Metaphors As Storehouses of Expectation.

    ERIC Educational Resources Information Center

    Beavis, Allan K.; Thomas, A. Ross

    1996-01-01

    Explores how metaphors are used to identify and store some expectations that structure schools' interactions and communications. Outlines a systems-theoretical view of schools derived from Niklas Luhmann's social theories. Illustrates how the metaphors identified in an earlier study provide material contexts for identifying and storing structures…

  1. Undergraduates' Perceptions of Employer Expectations

    ERIC Educational Resources Information Center

    DuPre, Carrie; Williams, Kate

    2011-01-01

    Research conducted by the National Association of Colleges and Employers (NACE) indicates that employers across industries seek similar skills in job applicants; yet employers often report finding these desired skills lacking in new hires. This study closes the gap in understanding between employer expectations and student perceptions regarding

  2. Primary expectations of secondary metabolites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant secondary metabolites (e.g., phenolics) are important for human health, in addition to the organoleptic properties they impart to fresh and processed foods. Consumer expectations such as appearance, taste, or texture influence their purchasing decisions. Thorough identification of phenolic com...

  3. Kidney Failure: What to Expect

    MedlinePLUS

    ... Fund National Kidney Foundation Renal Support Network MedlinePlus Kidney and Urologic Disease Organizations Many organizations provide support ... Organizations​​ . (PDF, 345 KB)​​​​​ Alternate Language URL Español Kidney Failure: What to Expect Page Content On this ...

  4. Just What Do You Expect?

    ERIC Educational Resources Information Center

    Mason, Philip R.

    1990-01-01

    Boards should clearly establish what is expected of the university president, including the six elements of good leadership: tolerance of freedom, tolerance of uncertainty, the ability to integrate motives and efforts into a meaningful aggregate, the ability to persuade, the ability to represent the institution, and influence with superiors. (MSE)

  5. Evaluation of Behavioral Expectation Scales.

    ERIC Educational Resources Information Center

    Zedeck, Sheldon; Baker, Henry T.

    Behavioral Expectation Scales developed by Smith and Kendall were evaluated. Results indicated slight interrater reliability between Head Nurses and Supervisors, moderate dependence among five performance dimensions, and correlation between two scales and tenure. Results are discussed in terms of procedural problems, critical incident problems,

  6. Privacy Expectations in Online Contexts

    ERIC Educational Resources Information Center

    Pure, Rebekah Abigail

    2013-01-01

    Advances in digital networked communication technology over the last two decades have brought the issue of personal privacy into sharper focus within contemporary public discourse. In this dissertation, I explain the Fourth Amendment and the role that privacy expectations play in the constitutional protection of personal privacy generally, and…

  7. Career Expectations of Accounting Students

    ERIC Educational Resources Information Center

    Elam, Dennis; Mendez, Francis

    2010-01-01

    The demographic make-up of accounting students is dramatically changing. This study sets out to measure how well the profession is ready to accommodate what may be very different needs and expectations of this new generation of students. Non-traditional students are becoming more and more of a tradition in the current college classroom.…

  8. Biomass utilization

    SciTech Connect

    Cote, W.A.

    1983-01-01

    Proceedings are given of the NATO Advanced Study Institute on biomass utilization. The course was introduced by discussion of the basic concepts of biomass utilization. Then the raw material (forest biomass, agricultural resources, aquatic resources and municipal solid waste) was considered from the point of view of its availability, assessment, preparation and general suitability. The structure and chemical composition of the biomass were addressed by a number of speakers before the conversion methods were presented. Biological and thermochemical routes for conversion of biomass to energy, chemicals or food were discussed for several days as this is the main thrust of biomass utilization today. Finally, the engineering aspects and the economics of biomass utilization were taken up in order to examine the feasibility of the various elements that comprise this multidisciplinary field. Separate abstracts have been prepared for items within the scope of the Energy Data Base.

  9. Maximal energy extraction under discrete diffusive exchange

    NASA Astrophysics Data System (ADS)

    Hay, M. J.; Schiff, J.; Fisch, N. J.

    2015-10-01

    Waves propagating through a bounded plasma can rearrange the densities of states in the six-dimensional velocity-configuration phase space. Depending on the rearrangement, the wave energy can either increase or decrease, with the difference taken up by the total plasma energy. In the case where the rearrangement is diffusive, only certain plasma states can be reached. It turns out that the set of reachable states through such diffusive rearrangements has been described in very different contexts. Building upon those descriptions, and making use of the fact that the plasma energy is a linear functional of the state densities, the maximal extractable energy under diffusive rearrangement can then be addressed through linear programming.

  10. Maximally polarized states for quantum light fields

    SciTech Connect

    Sanchez-Soto, Luis L.; Yustas, Eulogio C.; Bjoerk, Gunnar; Klimov, Andrei B.

    2007-10-15

    The degree of polarization of a quantum field can be defined as its distance to an appropriate set of states. When we take unpolarized states as this reference set, the states optimizing this degree for a fixed average number of photons N present a fairly symmetric, parabolic photon statistic, with a variance scaling as N{sup 2}. Although no standard optical process yields such a statistic, we show that, to an excellent approximation, a highly squeezed vacuum can be taken as maximally polarized. We also consider the distance of a field to the set of its SU(2) transformed, finding that certain linear superpositions of SU(2) coherent states make this degree to be unity.

  11. Dispatch Scheduling to Maximize Exoplanet Detection

    NASA Astrophysics Data System (ADS)

    Johnson, Samson; McCrady, Nate; MINERVA

    2016-01-01

    MINERVA is a dedicated exoplanet detection telescope array using radial velocity measurements of nearby stars to detect planets. MINERVA will be a completely robotic facility, with a goal of maximizing the number of exoplanets detected. MINERVA requires a unique application of queue scheduling due to its automated nature and the requirement of high cadence observations. A dispatch scheduling algorithm is employed to create a dynamic and flexible selector of targets to observe, in which stars are chosen by assigning values through a weighting function. I designed and have begun testing a simulation which implements the functions of a dispatch scheduler and records observations based on target selections through the same principles that will be used at the commissioned site. These results will be used in a larger simulation that incorporates weather, planet occurrence statistics, and stellar noise to test the planet detection capabilities of MINERVA. This will be used to heuristically determine an optimal observing strategy for the MINERVA project.

  12. Optimum Drop Height for Maximizing Power Output in Drop Jump: The Effect of Maximal Muscle Strength.

    PubMed

    Matic, Milan S; Pazin, Nemanja R; Mrdakovic, Vladimir D; Jankovic, Nenad N; Ilic, Dusko B; Stefanovic, Djordje L J

    2015-12-01

    The main purpose of this study was to explore the cause-and-effect relation of maximal muscle strength (MSmax) on the optimum drop height (DHopt) that maximizes power output in drop jump. In total, 30 physically active male students participated in this study, whereas the 16 subjects were selected according to their resistance strength training background (i.e., level of MSmax) and allocated into 2 equal subgroups: strong (n = 8) and weak (n = 8). The main testing session consisted of drop jumps performed from 8 different drop heights (i.e., from 0.12 to 0.82 m). The individual DHopt was determined based on the maximal value power output across applied ranges of drop heights. The tested relationships between DHopt and MSmax were moderate (r = 0.39-0.50, p ? 0.05). In addition, the stronger individuals, on average, showed maximal values of power output on the higher drop height compared with the weaker individuals (0.62 vs. 0.32 m). Finally, significant differences in the individual DHopt between groups were detected (p < 0.01). The present findings suggest that drop height should be adjusted based on a subject's neuromuscular capacity to produce MSmax. Hence, from the perspective of strength and conditioning practitioners, MSmax should be considered as an important factor that could affect the DHopt, and therefore should be used for its adjustment in terms of optimizing athlete's testing, training, or rehabilitation intervention. PMID:26020711

  13. Anaerobic contribution during maximal anaerobic running test: correlation with maximal accumulated oxygen deficit.

    PubMed

    Zagatto, A; Redkva, P; Loures, J; Kalva Filho, C; Franco, V; Kaminagakura, E; Papoti, M

    2011-12-01

    The aims of this study were: (i) to measure energy system contributions in maximal anaerobic running test (MART); and (ii) to verify any correlation between MART and maximal accumulated oxygen deficit (MAOD). Eleven members of the armed forces were recruited for this study. Participants performed MART and MAOD, both accomplished on a treadmill. MART consisted of intermittent exercise, 20 s effort with 100 s recovery, after each spell of effort exercise. Energy system contributions by MART were also determined by excess post-exercise oxygen consumption, lactate response, and oxygen uptake measurements. MAOD was determined by five submaximal intensities and one supramaximal intensity exercises corresponding to 120% at maximal oxygen uptake intensity. Energy system contributions were 65.4±1.1% to aerobic; 29.5±1.1% to anaerobic a-lactic; and 5.1±0.5% to anaerobic lactic system throughout the whole test, while only during effort periods the anaerobic contribution corresponded to 73.5±1.0%. Maximal power found in MART corresponded to 111.25±1.33 mL/kg/min but did not significantly correlate with MAOD (4.69±0.30 L and 70.85±4.73 mL/kg). We concluded that the anaerobic a-lactic system is the main energy system in MART efforts and this test did not significantly correlate to MAOD. PMID:21210856

  14. Does Maximizing Information at the Cut Score Always Maximize Classification Accuracy and Consistency?

    ERIC Educational Resources Information Center

    Wyse, Adam E.; Babcock, Ben

    2016-01-01

    A common suggestion made in the psychometric literature for fixed-length classification tests is that one should design tests so that they have maximum information at the cut score. Designing tests in this way is believed to maximize the classification accuracy and consistency of the assessment. This article uses simulated examples to illustrate…

  15. From entropy-maximization to equality-maximization: Gauss, Laplace, Pareto, and Subbotin

    NASA Astrophysics Data System (ADS)

    Eliazar, Iddo

    2014-12-01

    The entropy-maximization paradigm of statistical physics is well known to generate the omnipresent Gauss law. In this paper we establish an analogous socioeconomic model which maximizes social equality, rather than physical disorder, in the context of the distributions of income and wealth in human societies. We show that-on a logarithmic scale-the Laplace law is the socioeconomic equality-maximizing counterpart of the physical entropy-maximizing Gauss law, and that this law manifests an optimized balance between two opposing forces: (i) the rich and powerful, striving to amass ever more wealth, and thus to increase social inequality; and (ii) the masses, struggling to form more egalitarian societies, and thus to increase social equality. Our results lead from log-Gauss statistics to log-Laplace statistics, yield Paretian power-law tails of income and wealth distributions, and show how the emergence of a middle-class depends on the underlying levels of socioeconomic inequality and variability. Also, in the context of asset-prices with Laplace-distributed returns, our results imply that financial markets generate an optimized balance between risk and predictability.

  16. Mutually Unbiasedness between Maximally Entangled Bases and Unextendible Maximally Entangled Systems in C2? C^{2k}

    NASA Astrophysics Data System (ADS)

    Zhang, Jun; Nan, Hua; Tao, Yuan-Hong; Fei, Shao-Ming

    2016-02-01

    The mutually unbiasedness between a maximally entangled basis (MEB) and an unextendible maximally entangled system (UMES) in the bipartite system C2? C^{2k} (k>1) are introduced and discussed first in this paper. Then two mutually unbiased pairs of a maximally entangled basis and an unextendible maximally entangled system are constructed; lastly, explicit constructions are obtained for mutually unbiased MEB and UMES in C2? C4 and C2? C8, respectively.

  17. Overestimate of relative aerobic contribution with maximal accumulated oxygen deficit: a review.

    PubMed

    Li, Y; Niessen, M; Chen, X; Hartmann, U

    2015-05-01

    Maximal accumulated oxygen deficit (MAOD) is widely utilized in calculating energy production during supra-maximal exercises. Since its introduction by Medbo et al. in 1988, debate on MAOD existed. The purpose of this review was to summarize the development and description of MAOD and another method of calculating energy production (Pcr-La-O₂). We reviewed similar studies on relative aerobic contribution (O₂%) and analyzed various results of O₂% calculated using MAOD or Pcr-La-O₂. An overestimate of O₂% was found when using MAOD compared to Pcr-La-O₂. The overestimate when using MAOD is likely due to the linear extrapolation of oxygen uptake at supra-maximal intensity, the neglect of anaerobic energy release and the reduced duration of each step in sub-maximal incremental test. Since it is unknown which method provides a more reliable estimation of O₂%, an exponential regression function (y=22.404 * ex + 45.176, where y=O₂% in percentage, x=duration of the supra-maximal exercise in minute) was drawn from the existing data using both methods. PMID:25303069

  18. Maximal tori of a general Lie algebra of Cartan type

    NASA Astrophysics Data System (ADS)

    Kuznetsov, M. I.

    1997-10-01

    A description is given of all maximal tori in the p-closure of a general Lie algebra W(\\mathscr F) of Cartan type over an algebraically closed field of characteristics of tori are found (dimension, algebra of invariants, weight functions root subspaces, the centralizer of a maximal torus) in terms of a defining system of functions of a maximal torus, and criteria are obtained for standartness and optimality of a maximal torus. A connection is established between the maximal tori in the p-closure and the Cartan subalgebras of W(\\mathscr F).

  19. Utility Green Pricing Programs: A Statistical Analysis of Program Effectiveness

    SciTech Connect

    Wiser, R.; Olson, S.; Bird, L.; Swezey, B.

    2004-02-01

    This report analyzes actual utility green pricing program data to provide further insight into which program features might help maximize both customer participation in green pricing programs and the amount of renewable energy purchased by customers in those programs.

  20. Splitting an Arbitrary Two-ubit State Via a Seven-qubit Maximally Entangled State

    NASA Astrophysics Data System (ADS)

    Chen, Yan

    2015-05-01

    We investigate the usefulness of a recently introduced seven-qubit maximally entangled state by Zha et al. (J. Phys. A: Math. Theor. 45:255-302, [10]) for quantum information splitting. It is shown that such a seven-qubit entangled state can be utilized for quantum information splitting of an arbitrary two-qubit state by performing only the Bell-state measurements.

  1. Quantum Mechanics and the Principle of Maximal Variety

    NASA Astrophysics Data System (ADS)

    Smolin, Lee

    2016-03-01

    Quantum mechanics is derived from the principle that the universe contain as much variety as possible, in the sense of maximizing the distinctiveness of each subsystem. The quantum state of a microscopic system is defined to correspond to an ensemble of subsystems of the universe with identical constituents and similar preparations and environments. A new kind of interaction is posited amongst such similar subsystems which acts to increase their distinctiveness, by extremizing the variety. In the limit of large numbers of similar subsystems this interaction is shown to give rise to Bohm's quantum potential. As a result the probability distribution for the ensemble is governed by the Schroedinger equation. The measurement problem is naturally and simply solved. Microscopic systems appear statistical because they are members of large ensembles of similar systems which interact non-locally. Macroscopic systems are unique, and are not members of any ensembles of similar systems. Consequently their collective coordinates may evolve deterministically. This proposal could be tested by constructing quantum devices from entangled states of a modest number of quits which, by its combinatorial complexity, can be expected to have no natural copies.

  2. Maximally localized Wannier functions: Theory and applications

    NASA Astrophysics Data System (ADS)

    Marzari, Nicola; Mostofi, Arash A.; Yates, Jonathan R.; Souza, Ivo; Vanderbilt, David

    2012-10-01

    The electronic ground state of a periodic system is usually described in terms of extended Bloch orbitals, but an alternative representation in terms of localized “Wannier functions” was introduced by Gregory Wannier in 1937. The connection between the Bloch and Wannier representations is realized by families of transformations in a continuous space of unitary matrices, carrying a large degree of arbitrariness. Since 1997, methods have been developed that allow one to iteratively transform the extended Bloch orbitals of a first-principles calculation into a unique set of maximally localized Wannier functions, accomplishing the solid-state equivalent of constructing localized molecular orbitals, or “Boys orbitals” as previously known from the chemistry literature. These developments are reviewed here, and a survey of the applications of these methods is presented. This latter includes a description of their use in analyzing the nature of chemical bonding, or as a local probe of phenomena related to electric polarization and orbital magnetization. Wannier interpolation schemes are also reviewed, by which quantities computed on a coarse reciprocal-space mesh can be used to interpolate onto much finer meshes at low cost, and applications in which Wannier functions are used as efficient basis functions are discussed. Finally the construction and use of Wannier functions outside the context of electronic-structure theory is presented, for cases that include phonon excitations, photonic crystals, and cold-atom optical lattices.

  3. Maximizing Exosome Colloidal Stability Following Electroporation

    PubMed Central

    Hood, Joshua L.; Scott, Michael J.; Wickline, Samuel A.

    2014-01-01

    Development of exosome based semi-synthetic nanovesicles for diagnostic and therapeutic purposes requires novel approaches to load exosomes with cargo. Electroporation has previously been used to load exosomes with RNA. However, investigations into exosome colloidal stability following electroporation have not been considered. Herein, we report the development of a unique trehalose pulse media (TPM) that minimizes exosome aggregation following electroporation. Dynamic light scattering (DLS) and RNA absorbance were employed to determine the extent of exosome aggregation and electroextraction post electroporation in TPM compared to common PBS pulse media or sucrose pulse media (SPM). Use of TPM to disaggregate melanoma exosomes post electroporation was dependent on both exosome concentration and electric field strength. TPM maximized exosome dispersal post electroporation for both homogenous B16 melanoma and heterogeneous human serum derived populations of exosomes. Moreover, TPM enabled heavy cargo loading of melanoma exosomes with 5 nm superparamagnetic iron oxide nanoparticles (SPION5) while maintaining original exosome size and minimizing exosome aggregation as evidenced by transmission electron microscopy. Loading exosomes with SPION5 increased exosome density on sucrose gradients. This provides a simple, label free means to enrich exogenously modified exosomes and introduces the potential for MRI driven theranostic exosome investigations in vivo. PMID:24333249

  4. Predicting maximal grip strength using hand circumference.

    PubMed

    Li, Ke; Hewson, David J; Duchne, Jacques; Hogrel, Jean-Yves

    2010-12-01

    The objective of this study was to analyze the correlations between anthropometric data and maximal grip strength (MGS) in order to establish a simple model to predict "normal" MGS. Randomized bilateral measurement of MGS was performed on a homogeneous population of 100 subjects. MGS was measured according to a standardized protocol with three dynamometers (Jamar, Myogrip and Martin Vigorimeter) for both dominant and non-dominant sides. Several anthropometric data were also measured: height; weight; hand, wrist and forearm circumference; hand and palm length. Among these data, hand circumference had the strongest correlation with MGS for all three dynamometers and for both hands (0.789 and 0.782 for Jamar; 0.829 and 0.824 for Myogrip; 0.663 and 0.730 for Vigorimeter). In addition, the only anthropometric variable systematically selected by a stepwise multiple linear regression analysis was also hand circumference. Based on this parameter alone, a predictive regression model presented good results (r(2) = 0.624 for Jamar; r(2) = 0.683 for Myogrip and r(2) = 0.473 for Vigorimeter; all adjusted r(2)). Moreover a single equation was predictive of MGS for both men and women and for both non-dominant and dominant hands. "Normal" MGS can be predicted using hand circumference alone. PMID:20708427

  5. Rehabilitation Professionals' Participation Intensity and Expectations of Transition Roles

    ERIC Educational Resources Information Center

    Oertle, Kathleen Marie

    2009-01-01

    In this mixed-methods study, an on-line survey and interviews were utilized to gather data regarding the level of participation and expectations rehabilitation professionals have of teachers, youth with disabilities, parents, and themselves during the transition process. The survey response rate was 73.0% (N = 46). Six were selected for interviews

  6. Space expectations: Latest survey results

    NASA Astrophysics Data System (ADS)

    Raitt, David; Swan, Cathy; Swan, Peter; Woods, Arthur

    2010-11-01

    At the 59th IAC in Glasgow, a paper was presented describing two studies being carried out by Commission VI of the International Academy of Astronautics on the impact of space activities upon society. One of these studies sought to discover the hopes, aspirations and expectations of those outside the space field - the person in the street - regarding space activities. The paper reviewed the thought processes and decisions leading up to the commencement of the survey, documented the reasoning behind the questions which the public were; described the efforts to translate the questionnaire into the six Unesco languages to achieve wider participation, and provided an overview of results to date. This present paper provides an update on this Space Expectations survey as the study comes to a close. The paper briefly discusses the addition of new languages for the questionnaire and the drive to make the survey better known and encourage participation worldwide, before going on to provide a detailed analysis of the latest results of opinions. Insights include respondent's thoughts regarding the visions and costs of space activities, how much people feel part of them and whether and how they would like to be more involved.

  7. Primary Care Clinician Expectations Regarding Aging

    ERIC Educational Resources Information Center

    Davis, Melinda M.; Bond, Lynne A.; Howard, Alan; Sarkisian, Catherine A.

    2011-01-01

    Purpose: Expectations regarding aging (ERA) in community-dwelling older adults are associated with personal health behaviors and health resource usage. Clinicians' age expectations likely influence patients' expectations and care delivery patterns; yet, limited research has explored clinicians' age expectations. The Expectations Regarding Aging

  8. Practical applicability of Nyayas - (Maxims) mentioned in Chakrapani Tika.

    PubMed

    Vyas, Mahesh Kumar; Dwivedi, Rambabu

    2014-01-01

    The Nyayas - (Maxims) are of two types: (1) Loukika Nyaya and (2) Shastriya Nyaya. Loukika Nyayas are the one which are used by the common public in day today life whereas Shastriya Nyayas are the one which are used by the authors of the treatise to explore their concepts. Most commonly by using the meaning and gist of Loukika Nyaya, the Shastriya Nyayas were put forth by the Granthakaras. Moreover, notion of Nyaya depends upon the situation, place, and topic of explanation mainly. To explain the meaning of the topic, these Nyayas helped since Vaidika Kala. They teach hidden meaning correctly. As like Vedas, these Nyayas are also a part of other Shastras and so as in Ayurveda Shastra too. While explaining the Nidana, Chikitsa, etc., these Nyayas were utilized by the Acharyas of Ayurveda. To discern these Nyayas in their entirety at one place with examples is necessary for easy understanding of the Shastra. Here is an attempt to explore such Nyayas mentioned in Ayurveda for the benefit of easy understanding of the subject. PMID:26664230

  9. Regularized F-measure maximization for feature selection and classification.

    PubMed

    Liu, Zhenqiu; Tan, Ming; Jiang, Feng

    2009-01-01

    Receiver Operating Characteristic (ROC) analysis is a common tool for assessing the performance of various classifications. It gained much popularity in medical and other fields including biological markers and, diagnostic test. This is particularly due to the fact that in real-world problems misclassification costs are not known, and thus, ROC curve and related utility functions such as F-measure can be more meaningful performance measures. F-measure combines recall and precision into a global measure. In this paper, we propose a novel method through regularized F-measure maximization. The proposed method assigns different costs to positive and negative samples and does simultaneous feature selection and prediction with L(1) penalty. This method is useful especially when data set is highly unbalanced, or the labels for negative (positive) samples are missing. Our experiments with the benchmark, methylation, and high dimensional microarray data show that the performance of proposed algorithm is better or equivalent compared with the other popular classifiers in limited experiments. PMID:19421401

  10. Mammogram segmentation using maximal cell strength updation in cellular automata.

    PubMed

    Anitha, J; Peter, J Dinesh

    2015-08-01

    Breast cancer is the most frequently diagnosed type of cancer among women. Mammogram is one of the most effective tools for early detection of the breast cancer. Various computer-aided systems have been introduced to detect the breast cancer from mammogram images. In a computer-aided diagnosis system, detection and segmentation of breast masses from the background tissues is an important issue. In this paper, an automatic segmentation method is proposed to identify and segment the suspicious mass regions of mammogram using a modified transition rule named maximal cell strength updation in cellular automata (CA). In coarse-level segmentation, the proposed method performs an adaptive global thresholding based on the histogram peak analysis to obtain the rough region of interest. An automatic seed point selection is proposed using gray-level co-occurrence matrix-based sum average feature in the coarse segmented image. Finally, the method utilizes CA with the identified initial seed point and the modified transition rule to segment the mass region. The proposed approach is evaluated over the dataset of 70 mammograms with mass from mini-MIAS database. Experimental results show that the proposed approach yields promising results to segment the mass region in the mammograms with the sensitivity of 92.25% and accuracy of 93.48%. PMID:25841356

  11. Practical applicability of Nyayas – (Maxims) mentioned in Chakrapani Tika

    PubMed Central

    Vyas, Mahesh Kumar; Dwivedi, Rambabu

    2014-01-01

    The Nyayas – (Maxims) are of two types: (1) Loukika Nyaya and (2) Shastriya Nyaya. Loukika Nyayas are the one which are used by the common public in day today life whereas Shastriya Nyayas are the one which are used by the authors of the treatise to explore their concepts. Most commonly by using the meaning and gist of Loukika Nyaya, the Shastriya Nyayas were put forth by the Granthakaras. Moreover, notion of Nyaya depends upon the situation, place, and topic of explanation mainly. To explain the meaning of the topic, these Nyayas helped since Vaidika Kala. They teach hidden meaning correctly. As like Vedas, these Nyayas are also a part of other Shastras and so as in Ayurveda Shastra too. While explaining the Nidana, Chikitsa, etc., these Nyayas were utilized by the Acharyas of Ayurveda. To discern these Nyayas in their entirety at one place with examples is necessary for easy understanding of the Shastra. Here is an attempt to explore such Nyayas mentioned in Ayurveda for the benefit of easy understanding of the subject. PMID:26664230

  12. Rare flavor processes in Maximally Natural Supersymmetry

    NASA Astrophysics Data System (ADS)

    Garca, Isabel Garca; March-Russell, John

    2015-01-01

    We study CP-conserving rare flavor violating processes in the recently proposed theory of Maximally Natural Supersymmetry (MNSUSY). MNSUSY is an unusual supersymmetric (SUSY) extension of the Standard Model (SM) which, remarkably, is untuned at present LHC limits. It employs Scherk-Schwarz breaking of SUSY by boundary conditions upon compactifying an underlying 5-dimensional (5D) theory down to 4D, and is not well-described by softly-broken SUSY, with much different phenomenology than the Minimal Supersymmetric Standard Model (MSSM) and its variants. The usual CP-conserving SUSY-flavor problem is automatically solved in MNSUSY due to a residual almost exact U(1) R symmetry, naturally heavy and highly degenerate 1st- and 2nd-generation sfermions, and heavy gauginos and Higgsinos. Depending on the exact implementation of MNSUSY there exist important new sources of flavor violation involving gauge boson Kaluza-Klein (KK) excitations. The spatial localization properties of the matter multiplets, in particular the brane localization of the 3rd generation states, imply KK-parity is broken and tree-level contributions to flavor changing neutral currents are present in general. Nevertheless, we show that simple variants of the basic MNSUSY model are safe from present flavor constraints arising from kaon and B-meson oscillations, the rare decays B s, d ? ? + ? -, ? ? ?ee and ?- e conversion in nuclei. We also briefly discuss some special features of the radiative decays ? ? e? and . Future experiments, especially those concerned with lepton flavor violation, should see deviations from SM predictions unless one of the MNSUSY variants with enhanced flavor symmetries is realized.

  13. Maximal perfusion of skeletal muscle in man.

    PubMed Central

    Andersen, P; Saltin, B

    1985-01-01

    Five subjects exercised with the knee extensor of one limb at work loads ranging from 10 to 60 W. Measurements of pulmonary oxygen uptake, heart rate, leg blood flow, blood pressure and femoral arterial-venous differences for oxygen and lactate were made between 5 and 10 min of the exercise. Flow in the femoral vein was measured using constant infusion of saline near 0 degrees C. Since a cuff was inflated just below the knee during the measurements and because the hamstrings were inactive, the measured flow represented primarily the perfusion of the knee extensors. Blood flow increased linearly with work load right up to an average value of 5.7 l min-1. Mean arterial pressure was unchanged up to a work load of 30 W, but increased thereafter from 100 to 130 mmHg. The femoral arterial-venous oxygen difference at maximum work averaged 14.6% (v/v), resulting in an oxygen uptake of 0.80 l min-1. With a mean estimated weight of the knee extensors of 2.30 kg the perfusion of maximally exercising skeletal muscle of man is thus in the order of 2.5 l kg-1 min-1, and the oxygen uptake 0.35 l kg-1 min-1. Limitations in the methods used previously to determine flow and/or the characteristics of the exercise model used may explain why earlier studies in man have failed to demonstrate the high perfusion of muscle reported here. It is concluded that muscle blood flow is closely related to the oxygen demand of the exercising muscles. The hyperaemia at low work intensities is due to vasodilatation, and an elevated mean arterial blood pressure only contributes to the linear increase in flow at high work rates. The magnitude of perfusion observed during intense exercise indicates that the vascular bed of skeletal muscle is not a limiting factor for oxygen transport. PMID:4057091

  14. An expectation-based memory deficit in aging.

    PubMed

    Bollinger, Jacob; Rubens, Michael T; Masangkay, Edrick; Kalkstein, Jonathan; Gazzaley, Adam

    2011-05-01

    Memory performance can be enhanced by expectations regarding the appearance of ensuing stimuli. Here, we investigated the influence of stimulus-category expectation on memory performance in aging, and used fMRI to explore age-related alterations in associated neural mechanisms. Unlike younger adults, who demonstrated both working memory (WM) and long-term memory (LTM) performance benefits for face stimuli when this stimulus category was expected, older adults did not exhibit these memory benefits. Concordantly, older adults did not exhibit expectation-period activity modulation in visual association cortex (i.e., fusiform face area (FFA)), unlike younger adults. However, within the older population, individuals who demonstrated face-expectation memory benefits also exhibited expectation-period FFA activity modulation equivalent to younger adults. The older cohort also displayed diminished expectation-related functional connectivity between regions of the prefrontal cortex and the FFA, relative to younger adults, suggesting that network alterations underlie the absence of expectation-mediated cortical modulation and memory benefits. This deficit may have broader consequences for the effective utilization of predictive cues to guide attention and engender optimal cognitive performance in older individuals. PMID:21272595

  15. An expectation-based memory deficit in aging

    PubMed Central

    Bollinger, Jacob; Rubens, Michael T.; Masangkay, Edrick; Kalkstein, Jonathan; Gazzaley, Adam

    2011-01-01

    Memory performance can be enhanced by expectations regarding the appearance of ensuing stimuli. Here, we investigated the influence of stimulus-category expectation on memory performance in aging, and used fMRI to explore age-related alterations in associated neural mechanisms. Unlike younger adults, who demonstrated both working memory (WM) and long-term memory (LTM) performance benefits for face stimuli when this stimulus category was expected, older adults did not exhibit these memory benefits. Concordantly, older adults did not exhibit expectation-period activity modulation in visual association cortex (i.e., fusiform face area (FFA)). However, within the older population, individuals who demonstrated face-expectation memory benefits also exhibited expectation-period FFA activity modulation equivalent to younger adults. The older cohort also displayed diminished expectation-related functional connectivity between regions of the prefrontal cortex and the FFA, relative to younger adults, suggesting that network alterations underlie the absence of expectation-mediated cortical modulation and memory benefits. This deficit may have broader consequences for the effective utilization of predictive cues to guide attention and engender optimal cognitive performance in older individuals. PMID:21272595

  16. Utility Function from Maximum Entropy Principle

    NASA Astrophysics Data System (ADS)

    Darooneh, Amir H.

    2006-03-01

    Recently we used the maximum entropy principle for finding the price density in a multi agent insurance market. The result is similar to what the Buhlmann had obtained by maximizing the utility function. Here we begin with the price density that is derived by applying the maximum entropy principle to a conservative economic system (exchange market), then reverse the Buhlmann calculation to find the utility function and the risk aversion of agents with respect to this density.

  17. Improving Simulated Annealing by Replacing Its Variables with Game-Theoretic Utility Maximizers

    NASA Technical Reports Server (NTRS)

    Wolpert, David H.; Bandari, Esfandiar; Tumer, Kagan

    2001-01-01

    The game-theory field of Collective INtelligence (COIN) concerns the design of computer-based players engaged in a non-cooperative game so that as those players pursue their self-interests, a pre-specified global goal for the collective computational system is achieved as a side-effect. Previous implementations of COIN algorithms have outperformed conventional techniques by up to several orders of magnitude, on domains ranging from telecommunications control to optimization in congestion problems. Recent mathematical developments have revealed that these previously developed algorithms were based on only two of the three factors determining performance. Consideration of only the third factor would instead lead to conventional optimization techniques like simulated annealing that have little to do with non-cooperative games. In this paper we present an algorithm based on all three terms at once. This algorithm can be viewed as a way to modify simulated annealing by recasting it as a non-cooperative game, with each variable replaced by a player. This recasting allows us to leverage the intelligent behavior of the individual players to substantially improve the exploration step of the simulated annealing. Experiments are presented demonstrating that this recasting significantly improves simulated annealing for a model of an economic process run over an underlying small-worlds topology. Furthermore, these experiments reveal novel small-worlds phenomena, and highlight the shortcomings of conventional mechanism design in bounded rationality domains.

  18. Maximizing clozapine utilization while minimizing blood dyscrasias: evaluation of patient demographics and severity of events.

    PubMed

    Demler, Tammie Lee; Morabito, Nicole E; Meyer, Charlene E; Opler, Lewis

    2016-03-01

    The aim of this study was to determine whether patient characteristics such as age, sex, race/ethnicity, and frequency of monitoring play a role in clozapine-related blood dyscrasias. This study examined all neutropenic events to identify any potential demographic qualities that may pose increased risk to individuals receiving clozapine treatment in accordance with the FDA guidelines released in 2005. These guidelines required the addition of absolute neutrophil count (ANC) tests in addition to white blood cell (WBC) counts to regular monitoring and a reduction in the frequency of testing to once monthly after 1 year of satisfactory WBC counts and ANCs. The previous schedule neither included ANC testing nor allowed for further reductions in the frequency of testing after 1 year, with patients continuing to be tested every 2 weeks indefinitely. This is a retrospective, closed chart review of all patients who received clozapine at the State Psychiatric Center and experienced a leukopenic/neutropenic event and/or who had a substantial drop in WBC/ANC from January 2009 to December 2011. A subset of patients who were identified as achieving 'non-rechallengeable' status with either an ANC and/or WBC threshold value from 2001 to 2014 were also examined. This protocol was approved by the New York State Psychiatric Institute Institutional Review Board. A total of 193 patients were included in the study. Males experienced more total events at 6.4 events per person compared with 5.2 events per woman. White patients had 6.5 total events per person compared with 4.2 total events per Black patient; however, Black patients experienced more moderate leukopenia/granulocytopenia events compared with Whites. Regardless of race or ethnicity, patients in the 40-49-year age range had the most events at 8.1 events per person and also presented with the highest number of moderate leukopenia/granulocytopenia events as did those scheduled for weekly monitoring. Conversely, the majority of patients with no recorded events were female and either 20-29 or 60-69 years of age. In total, 16 patients were exclusively designated as non-rechallengeable from 2001 to 2014 and only had one single blood event prompting this clozapine monitoring status. Of these 16 patient events, seven were White males, eight were White females, and one was a Black female with roughly 40% of those patients in the 50-59-year age group. Currently published predictions on possible demographic risk groups may not reflect clinical experience and may pose unnecessary treatment barriers in the provision of clozapine. Although the healthcare team should be aware of the possible demographic predictors of blood dyscrasias when using clozapine, treatment goals and monitoring strategies must be individualized to ensure successful clozapine therapy. PMID:26565383

  19. 76 FR 49473 - Petition to Maximize Practical Utility of List 1 Chemicals Screened Through EPA's Endocrine...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-10

    ...EPA is seeking public comment on a June 21, 2011, petition from CropLife America (CLA), Consumer Specialty Products Association (CSPA), and the Responsible Industry for a Sound Environment (RISE) requesting the Agency develop and publish guidance explaining the criteria by which EPA will make its decisions on data received in response to the test orders issued under the Endocrine Disruptor......

  20. A sampling plan for conduit-flow karst springs: Minimizing sampling cost and maximizing statistical utility

    USGS Publications Warehouse

    Currens, J.C.

    1999-01-01

    Analytical data for nitrate and triazines from 566 samples collected over a 3-year period at Pleasant Grove Spring, Logan County, KY, were statistically analyzed to determine the minimum data set needed to calculate meaningful yearly averages for a conduit-flow karst spring. Results indicate that a biweekly sampling schedule augmented with bihourly samples from high-flow events will provide meaningful suspended-constituent and dissolved-constituent statistics. Unless collected over an extensive period of time, daily samples may not be representative and may also be autocorrelated. All high-flow events resulting in a significant deflection of a constituent from base-line concentrations should be sampled. Either the geometric mean or the flow-weighted average of the suspended constituents should be used. If automatic samplers are used, then they may be programmed to collect storm samples as frequently as every few minutes to provide details on the arrival time of constituents of interest. However, only samples collected bihourly should be used to calculate averages. By adopting a biweekly sampling schedule augmented with high-flow samples, the need to continuously monitor discharge, or to search for and analyze existing data to develop a statistically valid monitoring plan, is lessened.Analytical data for nitrate and triazines from 566 samples collected over a 3-year period at Pleasant Grove Spring, Logan County, KY, were statistically analyzed to determine the minimum data set needed to calculate meaningful yearly averages for a conduit-flow karst spring. Results indicate that a biweekly sampling schedule augmented with bihourly samples from high-flow events will provide meaningful suspended-constituent and dissolved-constituent statistics. Unless collected over an extensive period of time, daily samples may not be representative and may also be autocorrelated. All high-flow events resulting in a significant deflection of a constituent from base-line concentrations should be sampled. Either the geometric mean or the flow-weighted average of the suspended constituents should be used. If automatic samplers are used, then they may be programmed to collect storm samples as frequently as every few minutes to provide details on the arrival time of constituents of interest. However, only samples collected bihourly should be used to calculate averages. By adopting a biweekly sampling schedule augmented with high-flow samples, the need to continuously monitor discharge, or to search for and analyze existing data to develop a statistically valid monitoring plan, is lessened.

  1. Effective multisite CD correlation to maximize high-end tool utilization

    NASA Astrophysics Data System (ADS)

    Duff, John W.; Allsop, John

    1999-04-01

    The semiconductor industry continues to accelerate its pace following the SIA roadmap. Many technical and business issues are exacerbated by this acceleration. One such obstacle that faces the mask making community touches on both the business and the technical aspects of the industry's desire to pull in the target dates for each roadmap node. In order to provide the industry with adequate high end capacity on a global basis, the multi-site global photomask company must routinely exercise inter-site transfer for the purpose of leveling the manufacturing loads during periods of peak regional demand. A crucial part of inter-site transfer is to ensure that common standards are used, the deviation from those standards are understood, and a statistics based methodology for correlating metrology equipment is developed. Minimizing critical dimension correlation deltas between sites is critical to successful load leveling in an era of ever shrinking error budgets. This paper will explore the methods and practices used by Photronics to achieve routine inter-site measurements correlations whose precision far exceeds those of the best available standards. Both the statistical methods employed and the results from a large sample of production plates will be reported.

  2. Ground truth spectrometry and imagery of eruption clouds to maximize utility of satellite imagery

    NASA Technical Reports Server (NTRS)

    Rose, William I.

    1993-01-01

    Field experiments with thermal imaging infrared radiometers were performed and a laboratory system was designed for controlled study of simulated ash clouds. Using AVHRR (Advanced Very High Resolution Radiometer) thermal infrared bands 4 and 5, a radiative transfer method was developed to retrieve particle sizes, optical depth and particle mass involcanic clouds. A model was developed for measuring the same parameters using TIMS (Thermal Infrared Multispectral Scanner), MODIS (Moderate Resolution Imaging Spectrometer), and ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer). Related publications are attached.

  3. 77 FR 46069 - Proposed Guidelines for Ensuring and Maximizing the Quality, Objectivity, Utility, and Integrity...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-02

    ... published on January 3, 2002, at 67 FR 369-378 (reprinted February 5, 2002, at 67 FR 5365). The Bureau's..., identified by the title of this notice, by any of the following methods: Electronic:...

  4. Maximizing semi-active vibration isolation utilizing a magnetorheological damper with an inner bypass configuration

    NASA Astrophysics Data System (ADS)

    Bai, Xian-Xu; Wereley, Norman M.; Hu, Wei

    2015-05-01

    A single-degree-of-freedom (SDOF) semi-active vibration control system based on a magnetorheological (MR) damper with an inner bypass is investigated in this paper. The MR damper employing a pair of concentric tubes, between which the key structure, i.e., the inner bypass, is formed and MR fluids are energized, is designed to provide large dynamic range (i.e., ratio of field-on damping force to field-off damping force) and damping force range. The damping force performance of the MR damper is modeled using phenomenological model and verified by the experimental tests. In order to assess its feasibility and capability in vibration control systems, the mathematical model of a SDOF semi-active vibration control system based on the MR damper and skyhook control strategy is established. Using an MTS 244 hydraulic vibration exciter system and a dSPACE DS1103 real-time simulation system, experimental study for the SDOF semi-active vibration control system is also conducted. Simulation results are compared to experimental measurements.

  5. Maximizing semi-active vibration isolation utilizing a magnetorheological damper with an inner bypass configuration

    SciTech Connect

    Bai, Xian-Xu; Wereley, Norman M.; Hu, Wei

    2015-05-07

    A single-degree-of-freedom (SDOF) semi-active vibration control system based on a magnetorheological (MR) damper with an inner bypass is investigated in this paper. The MR damper employing a pair of concentric tubes, between which the key structure, i.e., the inner bypass, is formed and MR fluids are energized, is designed to provide large dynamic range (i.e., ratio of field-on damping force to field-off damping force) and damping force range. The damping force performance of the MR damper is modeled using phenomenological model and verified by the experimental tests. In order to assess its feasibility and capability in vibration control systems, the mathematical model of a SDOF semi-active vibration control system based on the MR damper and skyhook control strategy is established. Using an MTS 244 hydraulic vibration exciter system and a dSPACE DS1103 real-time simulation system, experimental study for the SDOF semi-active vibration control system is also conducted. Simulation results are compared to experimental measurements.

  6. IMPORTANCE OF MITOCHONDRIAL PO2 IN MAXIMAL O2 TRANSPORT AND UTILIZATION: A THEORETICAL ANALYSIS

    PubMed Central

    Cano, I; Mickael, M; Gomez-Cabrero, D.; Tegnr, J; Roca, J; Wagner, PD

    2013-01-01

    In previous calculations of how the O2 transport system limits V?O2max, it was reasonably assumed that mitochondrial PO2 (PmO2) could be neglected (set to zero). However, in reality, PmO2 must exceed zero and the red cell to mitochondrion diffusion gradient may therefore be reduced, impairing diffusive transport of O2 and V?O2max. Accordingly, we investigated the influence of PmO2 on these calculations by coupling previously used equations for O2 transport to one for mitochondrial respiration relating mitochondrial V?O2 to PO2. This hyperbolic function, characterized by its P50 and V?MAX, allowed PmO2 to become a model output (rather than set to zero as previously). Simulations using data from exercising normal subjects showed that at V?O2max, PmO2was usually < 1 mm Hg, and that the effects on V?O2max were minimal. However, when O2 transport capacity exceeded mitochondrial V?MAX, or if P50 were elevated, PmO2 often reached double digit values, thereby reducing the diffusion gradient and significantly decreasing V?O2max. PMID:24012990

  7. Value out of the Rear of the Gin - Utilizing Cottonseed and Gin Wastes to Maximize Profits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The best way to tell how good of job you are doing in the gin is to look at what is coming out the rear of the gin. The gin takes the harvested cotton modules, conditions and separates it into different product streams; the lint into a marketable UD bale, the seed into storage (short or long term), ...

  8. Maximal Oxygen Uptake, Sweating and Tolerance to Exercise in the Heat

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.; Castle, B. L.; Ruff, W. K.

    1972-01-01

    The physiological mechanisms that facilitate acute acclimation to heat have not been fully elucidated, but the result is the establishment of a more efficient cardiovascular system to increase heat dissipation via increased sweating that allows the acclimated man to function with a cooler internal environment and to extend his performance. Men in good physical condition with high maximal oxygen uptakes generally acclimate to heat more rapidly and retain it longer than men in poorer condition. Also, upon first exposure trained men tolerate exercise in the heat better than untrained men. Both resting in heat and physical training in a cool environment confer only partial acclimation when first exposed to work in the heat. These observations suggest separate additive stimuli of metabolic heat from exercise and environmental heat to increase sweating during the acclimation process. However, the necessity of utilizing physical exercise during acclimation has been questioned. Bradbury et al. (1964) have concluded exercise has no effect on the course of heat acclimation since increased sweating can be induced by merely heating resting subjects. Preliminary evidence suggests there is a direct relationship between the maximal oxygen uptake and the capacity to maintain thermal regulation, particularly through the control of sweating. Since increased sweating is an important mechanism for the development of heat acclimation, and fit men have high sweat rates, it follows that upon initial exposure to exercise in the heat, men with high maximal oxygen uptakes should exhibit less strain than men with lower maximal oxygen uptakes. The purpose of this study was: (1) to determine if men with higher maximal oxygen uptakes exhibit greater tolerance than men with lower oxygen uptakes during early exposure to exercise in the heat, and (2) to investigate further the mechanism of the relationship between sweating and maximal work capacity.

  9. Graded expectations: Predictive processing and the adjustment of expectations during spoken language comprehension.

    PubMed

    Boudewyn, Megan A; Long, Debra L; Swaab, Tamara Y

    2015-09-01

    The goal of this study was to investigate the use of the local and global contexts for incoming words during listening comprehension. Local context was manipulated by presenting a target noun (e.g., "cake," "veggies") that was preceded by a word that described a prototypical or atypical feature of the noun (e.g., "sweet," "healthy"). Global context was manipulated by presenting the noun in a scenario that was consistent or inconsistent with the critical noun (e.g., a birthday party). Event-related potentials (ERPs) were examined at the feature word and at the critical noun. An N400 effect was found at the feature word, reflecting the effect of compatibility with the global context. Global predictability and the local feature word consistency interacted at the critical noun: A larger N200 was found to nouns that mismatched predictions when the context was maximally constraining, relative to nouns in the other conditions. A graded N400 response was observed at the critical noun, modulated by global predictability and feature consistency. Finally, post-N400 positivity effects of context updating were observed to nouns that were supported by one contextual cue (global/local) but were unsupported by the other. These results indicate that (1)?incoming words that are compatible with context-based expectations receive a processing benefit; (2)?when the context is sufficiently constraining, specific lexical items may be activated; and (3)?listeners dynamically adjust their expectations when input is inconsistent with their predictions, provided that the inconsistency has some level of support from either the global or the local context. PMID:25673006

  10. Feature Extraction Using Supervised Independent Component Analysis by Maximizing Class Distance

    NASA Astrophysics Data System (ADS)

    Sakaguchi, Yoshinori; Ozawa, Seiichi; Kotani, Manabu

    Recently, Independent Component Analysis (ICA) has been applied to not only problems of blind signal separation, but also feature extraction of patterns. However, the effectiveness of pattern features extracted by conventional ICA algorithms depends on pattern sets; that is, how patterns are distributed in the feature space. As one of the reasons, we have pointed out that ICA features are obtained by increasing only their independence even if the class information is available. In this context, we can expect that more high-performance features can be obtained by introducing the class information into conventional ICA algorithms. In this paper, we propose a supervised ICA (SICA) that maximizes Mahalanobis distance between features of different classes as well as maximize their independence. In the first experiment, two-dimensional artificial data are applied to the proposed SICA algorithm to see how maximizing Mahalanobis distance works well in the feature extraction. As a result, we demonstrate that the proposed SICA algorithm gives good features with high separability as compared with principal component analysis and a conventional ICA. In the second experiment, the recognition performance of features extracted by the proposed SICA is evaluated using the three data sets of UCI Machine Learning Repository. From the results, we show that the better recognition accuracy is obtained using our proposed SICA. Furthermore, we show that pattern features extracted by SICA are better than those extracted by only maximizing the Mahalanobis distance.

  11. Maximally epistemic interpretations of the quantum state and contextuality.

    PubMed

    Leifer, M S; Maroney, O J E

    2013-03-22

    We examine the relationship between quantum contextuality (in both the standard Kochen-Specker sense and in the generalized sense proposed by Spekkens) and models of quantum theory in which the quantum state is maximally epistemic. We find that preparation noncontextual models must be maximally epistemic, and these in turn must be Kochen-Specker noncontextual. This implies that the Kochen-Specker theorem is sufficient to establish both the impossibility of maximally epistemic models and the impossibility of preparation noncontextual models. The implication from preparation noncontextual to maximally epistemic then also yields a proof of Bell's theorem from an Einstein-Podolsky-Rosen-like argument. PMID:25166779

  12. Maximizing energy transfer in vibrofluidized granular systems

    NASA Astrophysics Data System (ADS)

    Windows-Yule, C. R. K.; Rosato, A. D.; Parker, D. J.; Thornton, A. R.

    2015-05-01

    Using discrete particle simulations validated by experimental data acquired using the positron emission particle tracking technique, we study the efficiency of energy transfer from a vibrating wall to a system of discrete, macroscopic particles. We demonstrate that even for a fixed input energy from the wall, energy conveyed to the granular system under excitation may vary significantly dependent on the frequency and amplitude of the driving oscillations. We investigate the manner in which the efficiency with which energy is transferred to the system depends on the system variables and determine the key control parameters governing the optimization of this energy transfer. A mechanism capable of explaining our results is proposed, and the implications of our findings in the research field of granular dynamics as well as their possible utilization in industrial applications are discussed.

  13. North Dome decision expected soon

    SciTech Connect

    Not Available

    1981-08-01

    Decisions soon will be made which will set in motion the development of Qatar's huge North Dome gas field. The government and state company, Qatar General Petroleum Corp. (QGPC) is studying the results of 2 feasibility studies on the economics of LNG export, although initially North Dome exploitation will be aimed at the domestic market. Decisions on the nature and timing of the North Dome development are the most important that have had to be faced in the short 10-yr history of the small Gulf state. The country's oil production is currently running at approximately 500,000 bpd, with 270,000 bpd originating from 3 offshore fields. Output is expected to decline through 1990, and it generally is accepted that there is little likelihood of further major crude discoveries. Therefore, Qatar has to begin an adjustment from an economy based on oil to one based on gas, while adhering to the underlying tenets of long-term conservation and industrial diversification.

  14. D2-brane Chern-Simons theories: F -maximization = a-maximization

    NASA Astrophysics Data System (ADS)

    Fluder, Martin; Sparks, James

    2016-01-01

    We study a system of N D2-branes probing a generic Calabi-Yau three-fold singularity in the presence of a non-zero quantized Romans mass n. We argue that the low-energy effective c N=2 Chern-Simons quiver gauge theory flows to a superconformal fixed point in the IR, and construct the dual AdS4 solution in massive IIA supergravity. We compute the free energy F of the gauge theory on S 3 using localization. In the large N limit we find F = c ( nN )1/3 a 2/3, where c is a universal constant and a is the a-function of the "parent" four-dimensional N=1 theory on N D3-branes probing the same Calabi-Yau singularity. It follows that maximizing F over the space of admissible R-symmetries is equivalent to maximizing a for this class of theories. Moreover, we show that the gauge theory result precisely matches the holographic free energy of the supergravity solution, and provide a similar matching of the VEV of a BPS Wilson loop operator.

  15. Evaluation of anti-hyperglycemic effect of Actinidia kolomikta (Maxim. etRur.) Maxim. root extract.

    PubMed

    Hu, Xuansheng; Cheng, Delin; Wang, Linbo; Li, Shuhong; Wang, Yuepeng; Li, Kejuan; Yang, Yingnan; Zhang, Zhenya

    2015-05-01

    This study aimed to evaluate the anti-hyperglycemic effect of ethanol extract from Actinidia kolomikta (Maxim. etRur.) Maxim. root (AKE).An in vitro evaluation was performed by using rat intestinal α-glucosidase (maltase and sucrase), the key enzymes linked with type 2 diabetes. And an in vivo evaluation was also performed by loading maltose, sucrose, glucose to normal rats. As a result, AKE showed concentration-dependent inhibition effects on rat intestinal maltase and rat intestinal sucrase with IC(50) values of 1.83 and 1.03mg/mL, respectively. In normal rats, after loaded with maltose, sucrose and glucose, administration of AKE significantly reduced postprandial hyperglycemia, which is similar to acarbose used as an anti-diabetic drug. High contents of total phenolics (80.49 ± 0.05mg GAE/g extract) and total flavonoids (430.69 ± 0.91mg RE/g extract) were detected in AKE. In conclusion, AKE possessed anti-hyperglycemic effects and the possible mechanisms were associated with its inhibition on α-glucosidase and the improvement on insulin release and/or insulin sensitivity as well. The anti-hyperglycemic activity possessed by AKE maybe attributable to its high contents of phenolic and flavonoid compounds. PMID:26051735

  16. Nonverbal Expectancy Effects in the Political Media.

    ERIC Educational Resources Information Center

    Corder, Lloyd E.

    Expectancy effects--the unconscious shaping of receiver behavior by signalling sender expectations--while recognized in science, have not been documented extensively from a communication perspective, nor are nonverbal aspects of expectancy effects fully known. Expectancy is a function of three elements, the sender's predisposition (including

  17. Maximal stochastic transport in the Lorenz equations

    NASA Astrophysics Data System (ADS)

    Agarwal, Sahil; Wettlaufer, J. S.

    2016-01-01

    We calculate the stochastic upper bounds for the Lorenz equations using an extension of the background method. In analogy with Rayleigh-Bnard convection the upper bounds are for heat transport versus Rayleigh number. As might be expected, the stochastic upper bounds are larger than the deterministic counterpart of Souza and Doering [1], but their variation with noise amplitude exhibits interesting behavior. Below the transition to chaotic dynamics the upper bounds increase monotonically with noise amplitude. However, in the chaotic regime this monotonicity depends on the number of realizations in the ensemble; at a particular Rayleigh number the bound may increase or decrease with noise amplitude. The origin of this behavior is the coupling between the noise and unstable periodic orbits, the degree of which depends on the degree to which the ensemble represents the ergodic set. This is confirmed by examining the close returns plots of the full solutions to the stochastic equations and the numerical convergence of the noise correlations. The numerical convergence of both the ensemble and time averages of the noise correlations is sufficiently slow that it is the limiting aspect of the realization of these bounds. Finally, we note that the full solutions of the stochastic equations demonstrate that the effect of noise is equivalent to the effect of chaos.

  18. Maximizing Singlet Fission by Intermolecular Packing.

    PubMed

    Wang, Linjun; Olivier, Yoann; Prezhdo, Oleg V; Beljonne, David

    2014-10-01

    A novel nonadiabatic molecular dynamics scheme is applied to study the singlet fission (SF) process in pentacene dimers as a function of longitudinal and lateral displacements of the molecular backbones. Detailed two-dimensional mappings of both instantaneous and long-term triplet yields are obtained, characterizing the advantageous and unfavorable stacking arrangements, which can be achieved by chemical substitutions to the bare pentacene molecule. We show that the SF rate can be increased by more than an order of magnitude through tuning the intermolecular packing, most notably when going from cofacial to the slipped stacked arrangements encountered in some pentacene derivatives. The simulations indicate that the SF process is driven by thermal electron-phonon fluctuations at ambient and high temperatures, expected in solar cell applications. Although charge-transfer states are key to construct continuous channels for SF, a large charge-transfer character of the photoexcited state is found to be not essential for efficient SF. The reported time domain study mimics directly numerous laser experiments and provides novel guidelines for designing efficient photovoltaic systems exploiting the SF process with optimum intermolecular packing. PMID:26278443

  19. Maximizing Exposure Therapy: An Inhibitory Learning Approach

    PubMed Central

    Craske, Michelle G.; Treanor, Michael; Conway, Chris; Zbozinek, Tomislav; Vervliet, Bram

    2014-01-01

    Exposure therapy is an effective approach for treating anxiety disorders, although a substantial number of individuals fail to benefit or experience a return of fear after treatment. Research suggests that anxious individuals show deficits in the mechanisms believed to underlie exposure therapy, such as inhibitory learning. Targeting these processes may help improve the efficacy of exposure-based procedures. Although evidence supports an inhibitory learning model of extinction, there has been little discussion of how to implement this model in clinical practice. The primary aim of this paper is to provide examples to clinicians for how to apply this model to optimize exposure therapy with anxious clients, in ways that distinguish it from a ‘fear habituation’ approach and ‘belief disconfirmation’ approach within standard cognitive-behavior therapy. Exposure optimization strategies include 1) expectancy violation, 2) deepened extinction, 3) occasional reinforced extinction, 4) removal of safety signals, 5) variability, 6) retrieval cues, 7) multiple contexts, and 8) affect labeling. Case studies illustrate methods of applying these techniques with a variety of anxiety disorders, including obsessive-compulsive disorder, posttraumatic stress disorder, social phobia, specific phobia, and panic disorder. PMID:24864005

  20. Expected geoneutrino signal at JUNO

    NASA Astrophysics Data System (ADS)

    Strati, Virginia; Baldoncini, Marica; Callegari, Ivan; Mantovani, Fabio; McDonough, William F.; Ricci, Barbara; Xhixha, Gerti

    2015-12-01

    Constraints on the Earth's composition and on its radiogenic energy budget come from the detection of geoneutrinos. The Kamioka Liquid scintillator Antineutrino Detector (KamLAND) and Borexino experiments recently reported the geoneutrino flux, which reflects the amount and distribution of U and Th inside the Earth. The Jiangmen Underground Neutrino Observatory (JUNO) neutrino experiment, designed as a 20 kton liquid scintillator detector, will be built in an underground laboratory in South China about 53 km from the Yangjiang and Taishan nuclear power plants, each one having a planned thermal power of approximately 18 GW. Given the large detector mass and the intense reactor antineutrino flux, JUNO aims not only to collect high statistics antineutrino signals from reactors but also to address the challenge of discriminating the geoneutrino signal from the reactor background. The predicted geoneutrino signal at JUNO is terrestrial neutrino unit (TNU), based on the existing reference Earth model, with the dominant source of uncertainty coming from the modeling of the compositional variability in the local upper crust that surrounds (out to approximately 500 km) the detector. A special focus is dedicated to the 6° × 4° local crust surrounding the detector which is estimated to contribute for the 44% of the signal. On the basis of a worldwide reference model for reactor antineutrinos, the ratio between reactor antineutrino and geoneutrino signals in the geoneutrino energy window is estimated to be 0.7 considering reactors operating in year 2013 and reaches a value of 8.9 by adding the contribution of the future nuclear power plants. In order to extract useful information about the mantle's composition, a refinement of the abundance and distribution of U and Th in the local crust is required, with particular attention to the geochemical characterization of the accessible upper crust where 47% of the expected geoneutrino signal originates and this region contributes the major source of uncertainty.

  1. The vortex-finding property of maximal center (and other) gauges

    SciTech Connect

    Faber, M.; Greensite, J.; Olejnik, S.; Yamada, D.

    1999-10-01

    The authors argue that the vortex-finding property of maximal center gauge, i.e. the ability of this gauge to locate center vortices inserted by hand on any given lattice, is the key to its success in extracting the vortex content of thermalized lattice configurations. The authors explain how this property comes about, and why it is expected not only in maximal center gauge, but also in an infinite class of gauge conditions based on adjoint-representation link variables. In principle, the vortex-finding property can be foiled by Gribov copies. This fact is relevant to a gauge-fixing procedure devised by Kovacs and Tomboulis, where they show that the loss of center dominance, found in their procedure, is explained by a corresponding loss of the vortex-finding property. The dependence of center dominance on the vortex-finding property is demonstrated numerically in a number of other gauges.

  2. Note on maximally entangled Eisert-Lewenstein-Wilkens quantum games

    NASA Astrophysics Data System (ADS)

    Bolonek-Lasoń, Katarzyna; Kosiński, Piotr

    2015-12-01

    Maximally entangled Eisert-Lewenstein-Wilkens games are analyzed. For a general class of gates defined in the previous papers of the first author, the general conditions are derived which allow to determine the form of gate leading to maximally entangled games. The construction becomes particularly simple provided one does distinguish between games differing by relabeling of strategies. Some examples are presented.

  3. Effect of Age and Other Factors on Maximal Heart Rate.

    ERIC Educational Resources Information Center

    Londeree, Ben R.; Moeschberger, Melvin L.

    1982-01-01

    To reduce confusion regarding reported effects of age on maximal exercise heart rate, a comprehensive review of the relevant English literature was conducted. Data on maximal heart rate after exercising with a bicycle, a treadmill, and after swimming were analyzed with regard to physical fitness and to age, sex, and racial differences. (Authors/PP)

  4. Pace's Maxims for Homegrown Library Projects. Coming Full Circle

    ERIC Educational Resources Information Center

    Pace, Andrew K.

    2005-01-01

    This article discusses six maxims by which to run library automation. The following maxims are discussed: (1) Solve only known problems; (2) Avoid changing data to fix display problems; (3) Aut viam inveniam aut faciam; (4) If you cannot make it yourself, buy something; (5) Kill the alligator closest to the boat; and (6) Just because yours is…

  5. Pace's Maxims for Homegrown Library Projects. Coming Full Circle

    ERIC Educational Resources Information Center

    Pace, Andrew K.

    2005-01-01

    This article discusses six maxims by which to run library automation. The following maxims are discussed: (1) Solve only known problems; (2) Avoid changing data to fix display problems; (3) Aut viam inveniam aut faciam; (4) If you cannot make it yourself, buy something; (5) Kill the alligator closest to the boat; and (6) Just because yours is

  6. Detrimental Relations of Maximization with Academic and Career Attitudes

    ERIC Educational Resources Information Center

    Dahling, Jason J.; Thompson, Mindi N.

    2013-01-01

    Maximization refers to a decision-making style that involves seeking the single best option when making a choice, which is generally dysfunctional because people are limited in their ability to rationally evaluate all options and identify the single best outcome. The vocational consequences of maximization are examined in two samples, college…

  7. Preschoolers Can Recognize Violations of the Gricean Maxims

    ERIC Educational Resources Information Center

    Eskritt, Michelle; Whalen, Juanita; Lee, Kang

    2008-01-01

    Grice ("Syntax and semantics: Speech acts", 1975, pp. 41-58, Vol. 3) proposed that conversation is guided by a spirit of cooperation that involves adherence to several conversational maxims. Three types of maxims were explored in the current study: 1) Quality, to be truthful; 2) Relation, to say only what is relevant to a conversation; and 3)

  8. Note on maximally entangled Eisert-Lewenstein-Wilkens quantum games

    NASA Astrophysics Data System (ADS)

    Bolonek-Laso?, Katarzyna; Kosi?ski, Piotr

    2015-10-01

    Maximally entangled Eisert-Lewenstein-Wilkens games are analyzed. For a general class of gates defined in the previous papers of the first author, the general conditions are derived which allow to determine the form of gate leading to maximally entangled games. The construction becomes particularly simple provided one does distinguish between games differing by relabeling of strategies. Some examples are presented.

  9. Detrimental Relations of Maximization with Academic and Career Attitudes

    ERIC Educational Resources Information Center

    Dahling, Jason J.; Thompson, Mindi N.

    2013-01-01

    Maximization refers to a decision-making style that involves seeking the single best option when making a choice, which is generally dysfunctional because people are limited in their ability to rationally evaluate all options and identify the single best outcome. The vocational consequences of maximization are examined in two samples, college

  10. Improving information technology to maximize fenestration energyefficiency

    SciTech Connect

    Arasteh, Dariush; Mitchell, Robin; Kohler, Christian; Huizenga,Charlie; Curcija, Dragan

    2001-06-06

    Improving software for the analysis of fenestration product energy efficiency and developing related information technology products that aid in optimizing the use of fenestration products for energy efficiency are essential steps toward ensuring that more efficient products are developed and that existing and emerging products are utilized in the applications where they will produce the greatest energy savings. Given the diversity of building types and designs and the climates in the U.S., no one fenestration product or set of properties is optimal for all applications. Future tools and procedures to analyze fenestration product energy efficiency will need to both accurately analyze fenestration product performance under a specific set of conditions and to look at whole fenestration product energy performance over the course of a yearly cycle and in the context of whole buildings. Several steps have already been taken toward creating fenestration product software that will provide the information necessary to determine which details of a fenestration product's design can be improved to have the greatest impact on energy efficiency, what effects changes in fenestration product design will have on the comfort parameters that are important to consumers, and how specific fenestration product designs will perform in specific applications. Much work remains to be done, but the energy savings potential justifies the effort. Information is relatively cheap compared to manufacturing. Information technology has already been responsible for many improvements in the global economy--it can similarly facilitate many improvements in fenestration product energy efficiency.

  11. Increasing inspection equipment productivity by utilizing factory automation SW on TeraScan 5XX systems

    NASA Astrophysics Data System (ADS)

    Jakubski, Thomas; Piechoncinski, Michal; Moses, Raphael; Bugata, Bharathi; Schmalfuss, Heiko; Köhler, Ines; Lisowski, Jan; Klobes, Jens; Fenske, Robert

    2009-01-01

    Especially for advanced masks the reticle inspection operation is a very significant cost factor, since it is a time consuming process and inspection tools are becoming disproportionately expensive. Analyzing and categorizing historical equipment utilization times of the reticle inspection tools however showed a significant amount of time which can be classified as non productive. In order to reduce the inspection costs the equipment utilization needed to be improved. The main contributors to non productive time were analyzed and several use cases identified, where automation utilizing a SECS1 equipment interface was expected to help to reduce these non productive times. The paper demonstrates how real time access to equipment utilization data can be applied to better control manufacturing resources. Scenarios are presented where remote monitoring and control of the inspection equipment can be used to avoid setup errors or save inspection time by faster response to problem situations. Additionally a solution to the second important need, the maximization of tool utilization in cases where not all of the intended functions are available, is explained. Both the models and the software implementation are briefly explained. For automation of the so called inspection strategy a new approach which allows separation of the business rules from the automation infrastructure was chosen. Initial results of inspection equipment performance data tracked through the SECS interface are shown. Furthermore a system integration overview is presented and examples of how the inspection strategy rules are implemented and managed are given.

  12. Institutional barriers to increased utilization of power plant ash in Maryland: analysis and recommendations. Final report

    SciTech Connect

    Hudson, J.F.; Stoler, M.; Demeter, C.; Farrell, S.O.

    1982-01-01

    This report is directed at the problems of disposal and utilization of coal fired power plant solid wastes in Maryland. Each year, Maryland and D.C. power plants produce over 0.8 million tons of fly ash, bottom ash, and boiler slag (collectively, 'ash') and this quantity is expected to increase to 1.5 million tons by 1990. While only a small fraction of these wastes is presently used as a resource, increased utilization is possible, thus decreasing the quantities landfilled. Given the potential for increased use, a question is whether the state can aid utilities in finding markets for their solid wastes, so that use can be maximized and disposal minimized. For example, if existing state and local regulations present unreasonable barriers which delay use, or make use impractical or expensive, such barriers should be removed. Positive actions might also be taken to increase utilization of the ash resource. Based on surveys of eight states and detailed analysis of the Maryland situation, this report presents the existing institutional barriers to increased ash use in Maryland. 'Institutional barriers' as used in this report refer to legal, regulatory, and administrative activities of government agents which impact utilization efforts. Along with the list of barriers, this report includes a detailed survey of the regulatory treatment of ash and standards for highway construction use of ash. The report also provides comparisons with other states and presents a set of potential remedies for consideration.

  13. Expectation-Based Control of Noise and Chaos

    NASA Technical Reports Server (NTRS)

    Zak, Michael

    2006-01-01

    A proposed approach to control of noise and chaos in dynamic systems would supplement conventional methods. The approach is based on fictitious forces composed of expectations governed by Fokker-Planck or Liouville equations that describe the evolution of the probability densities of the controlled parameters. These forces would be utilized as feedback control forces that would suppress the undesired diffusion of the controlled parameters. Examples of dynamic systems in which the approach is expected to prove beneficial include spacecraft, electronic systems, and coupled lasers.

  14. Maximal entanglement versus entropy for mixed quantum states

    SciTech Connect

    Wei, T.-C.; Goldbart, Paul M.; Kwiat, Paul G.; Nemoto, Kae; Munro, William J.; Verstraete, Frank

    2003-02-01

    Maximally entangled mixed states are those states that, for a given mixedness, achieve the greatest possible entanglement. For two-qubit systems and for various combinations of entanglement and mixedness measures, the form of the corresponding maximally entangled mixed states is determined primarily analytically. As measures of entanglement, we consider entanglement of formation, relative entropy of entanglement, and negativity; as measures of mixedness, we consider linear and von Neumann entropies. We show that the forms of the maximally entangled mixed states can vary with the combination of (entanglement and mixedness) measures chosen. Moreover, for certain combinations, the forms of the maximally entangled mixed states can change discontinuously at a specific value of the entropy. Along the way, we determine the states that, for a given value of entropy, achieve maximal violation of Bell's inequality.

  15. Learning to minimize efforts versus maximizing rewards: computational principles and neural correlates.

    PubMed

    Skvortsova, Vasilisa; Palminteri, Stefano; Pessiglione, Mathias

    2014-11-19

    The mechanisms of reward maximization have been extensively studied at both the computational and neural levels. By contrast, little is known about how the brain learns to choose the options that minimize action cost. In principle, the brain could have evolved a general mechanism that applies the same learning rule to the different dimensions of choice options. To test this hypothesis, we scanned healthy human volunteers while they performed a probabilistic instrumental learning task that varied in both the physical effort and the monetary outcome associated with choice options. Behavioral data showed that the same computational rule, using prediction errors to update expectations, could account for both reward maximization and effort minimization. However, these learning-related variables were encoded in partially dissociable brain areas. In line with previous findings, the ventromedial prefrontal cortex was found to positively represent expected and actual rewards, regardless of effort. A separate network, encompassing the anterior insula, the dorsal anterior cingulate, and the posterior parietal cortex, correlated positively with expected and actual efforts. These findings suggest that the same computational rule is applied by distinct brain systems, depending on the choice dimension-cost or benefit-that has to be learned. PMID:25411490

  16. The Constrained Maximal Expression Level Owing to Haploidy Shapes Gene Content on the Mammalian X Chromosome.

    PubMed

    Hurst, Laurence D; Ghanbarian, Avazeh T; Forrest, Alistair R R; Huminiecki, Lukasz

    2015-12-01

    X chromosomes are unusual in many regards, not least of which is their nonrandom gene content. The causes of this bias are commonly discussed in the context of sexual antagonism and the avoidance of activity in the male germline. Here, we examine the notion that, at least in some taxa, functionally biased gene content may more profoundly be shaped by limits imposed on gene expression owing to haploid expression of the X chromosome. Notably, if the X, as in primates, is transcribed at rates comparable to the ancestral rate (per promoter) prior to the X chromosome formation, then the X is not a tolerable environment for genes with very high maximal net levels of expression, owing to transcriptional traffic jams. We test this hypothesis using The Encyclopedia of DNA Elements (ENCODE) and data from the Functional Annotation of the Mammalian Genome (FANTOM5) project. As predicted, the maximal expression of human X-linked genes is much lower than that of genes on autosomes: on average, maximal expression is three times lower on the X chromosome than on autosomes. Similarly, autosome-to-X retroposition events are associated with lower maximal expression of retrogenes on the X than seen for X-to-autosome retrogenes on autosomes. Also as expected, X-linked genes have a lesser degree of increase in gene expression than autosomal ones (compared to the human/Chimpanzee common ancestor) if highly expressed, but not if lowly expressed. The traffic jam model also explains the known lower breadth of expression for genes on the X (and the Z of birds), as genes with broad expression are, on average, those with high maximal expression. As then further predicted, highly expressed tissue-specific genes are also rare on the X and broadly expressed genes on the X tend to be lowly expressed, both indicating that the trend is shaped by the maximal expression level not the breadth of expression per se. Importantly, a limit to the maximal expression level explains biased tissue of expression profiles of X-linked genes. Tissues whose tissue-specific genes are very highly expressed (e.g., secretory tissues, tissues abundant in structural proteins) are also tissues in which gene expression is relatively rare on the X chromosome. These trends cannot be fully accounted for in terms of alternative models of biased expression. In conclusion, the notion that it is hard for genes on the Therian X to be highly expressed, owing to transcriptional traffic jams, provides a simple yet robustly supported rationale of many peculiar features of X's gene content, gene expression, and evolution. PMID:26685068

  17. The Constrained Maximal Expression Level Owing to Haploidy Shapes Gene Content on the Mammalian X Chromosome

    PubMed Central

    Hurst, Laurence D.; Ghanbarian, Avazeh T.; Forrest, Alistair R. R.; Huminiecki, Lukasz

    2015-01-01

    X chromosomes are unusual in many regards, not least of which is their nonrandom gene content. The causes of this bias are commonly discussed in the context of sexual antagonism and the avoidance of activity in the male germline. Here, we examine the notion that, at least in some taxa, functionally biased gene content may more profoundly be shaped by limits imposed on gene expression owing to haploid expression of the X chromosome. Notably, if the X, as in primates, is transcribed at rates comparable to the ancestral rate (per promoter) prior to the X chromosome formation, then the X is not a tolerable environment for genes with very high maximal net levels of expression, owing to transcriptional traffic jams. We test this hypothesis using The Encyclopedia of DNA Elements (ENCODE) and data from the Functional Annotation of the Mammalian Genome (FANTOM5) project. As predicted, the maximal expression of human X-linked genes is much lower than that of genes on autosomes: on average, maximal expression is three times lower on the X chromosome than on autosomes. Similarly, autosome-to-X retroposition events are associated with lower maximal expression of retrogenes on the X than seen for X-to-autosome retrogenes on autosomes. Also as expected, X-linked genes have a lesser degree of increase in gene expression than autosomal ones (compared to the human/Chimpanzee common ancestor) if highly expressed, but not if lowly expressed. The traffic jam model also explains the known lower breadth of expression for genes on the X (and the Z of birds), as genes with broad expression are, on average, those with high maximal expression. As then further predicted, highly expressed tissue-specific genes are also rare on the X and broadly expressed genes on the X tend to be lowly expressed, both indicating that the trend is shaped by the maximal expression level not the breadth of expression per se. Importantly, a limit to the maximal expression level explains biased tissue of expression profiles of X-linked genes. Tissues whose tissue-specific genes are very highly expressed (e.g., secretory tissues, tissues abundant in structural proteins) are also tissues in which gene expression is relatively rare on the X chromosome. These trends cannot be fully accounted for in terms of alternative models of biased expression. In conclusion, the notion that it is hard for genes on the Therian X to be highly expressed, owing to transcriptional traffic jams, provides a simple yet robustly supported rationale of many peculiar features of X’s gene content, gene expression, and evolution. PMID:26685068

  18. Preschoolers can recognize violations of the Gricean maxims

    PubMed Central

    Eskritt, Michelle; Whalen, Juanita; Lee, Kang

    2010-01-01

    Grice (Syntax and semantics: Speech acts, 1975, pp. 41–58, Vol. 3) proposed that conversation is guided by a spirit of cooperation that involves adherence to several conversational maxims. Three types of maxims were explored in the current study: 1) Quality, to be truthful; 2) Relation, to say only what is relevant to a conversation; and 3) Quantity, to provide as much information as required. Three- to five-year-olds were tested to determine the age at which an awareness of these Gricean maxims emerges. Children requested the help of one of two puppets in finding a hidden sticker. One puppet always adhered to the maxim being tested, while the other always violated it. Consistently choosing the puppet that adhered to the maxim was considered indicative of an understanding of that maxim. The results indicate that children were initially only successful in the Relation condition. While in general, children performed better at first in the Quantity condition compared with the Quality condition, 3-year-olds never performed above chance in the Quantity condition. The findings of the present study indicate that preschool children are sensitive to the violation of the Relation, Quality, and Quantity maxims at least under some conditions. PMID:20953298

  19. A taxonomic approach to communicating maxims in interstellar messages

    NASA Astrophysics Data System (ADS)

    Vakoch, Douglas A.

    2011-02-01

    Previous discussions of interstellar messages that could be sent to extraterrestrial intelligence have focused on descriptions of mathematics, science, and aspects of human culture and civilization. Although some of these depictions of humanity have implicitly referred to our aspirations, this has not clearly been separated from descriptions of our actions and attitudes as they are. In this paper, a methodology is developed for constructing interstellar messages that convey information about our aspirations by developing a taxonomy of maxims that provide guidance for living. Sixty-six maxims providing guidance for living were judged for degree of similarity to each of other. Quantitative measures of the degree of similarity between all pairs of maxims were derived by aggregating similarity judgments across individual participants. These composite similarity ratings were subjected to a cluster analysis, which yielded a taxonomy that highlights perceived interrelationships between individual maxims and that identifies major classes of maxims. Such maxims can be encoded in interstellar messages through three-dimensional animation sequences conveying narratives that highlight interactions between individuals. In addition, verbal descriptions of these interactions in Basic English can be combined with these pictorial sequences to increase intelligibility. Online projects to collect messages such as the SETI Institute's Earth Speaks and La Tierra Habla, can be used to solicit maxims from participants around the world.

  20. Building hospital TQM teams: effective polarity analysis and maximization.

    PubMed

    Hurst, J B

    1996-09-01

    Building and maintaining teams require careful attention to and maximization of such polar opposites (¿polarities¿) as individual and team, directive and participatory leadership, task and process, and stability and change. Analyzing systematic elements of any polarity and listing blocks, supports, and flexible ways to maximize it will prevent the negative consequences that occur when treating a polarity like a solvable problem. Flexible, well-timed shifts from pole to pole result in the maximization of upside and minimization of downside consequences. PMID:10159641

  1. Office Employment Expectations of Business Students

    ERIC Educational Resources Information Center

    Brower, Edward B.

    1971-01-01

    This study was designed to determine (1) the office employment expectations of white and nonwhite business education students and (2) the effect of various factors on office employment expectations. (Author)

  2. Habit control expectancy for drinking, smoking, and eating.

    PubMed

    Schneider, H G; Busch, M N

    1998-01-01

    Habit-specific locus of control measures for drinking, smoking, and eating were compared to Rotter's general measure to evaluate the relationship between cognitive expectancy and substance use. For both smoking and eating, individuals who reported being addicted were significantly more external on the habit-specific expectancy measures. Measures of use, tolerance, and risk covaried more closely with the habit-specific scales than with the general scale. For eating behavior, the habit-specific scale and the compulsive eating measure were different only for individuals with a history of being overweight. The habit-specific expectancy measures were more closely related to indices of use and addiction than the general locus of control measure and should have greater utility for research and intervention. PMID:9768297

  3. PRODCOST: an electric utility generation simulation code

    SciTech Connect

    Hudson, II, C. R.; Reynolds, T. M.; Smolen, G. R.

    1981-02-01

    The PRODCOST computer code simulates the operation of an electric utility generation system. Through a probabilistic simulation the expected energy production, fuel consumption, and cost of operation for each plant are determined. Total system fuel consumption, energy generation by type, total generation costs, as well as system loss of load probability and expected unserved energy are also calculated.

  4. 10 CFR 63.304 - Reasonable expectation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Reasonable expectation. 63.304 Section 63.304 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DISPOSAL OF HIGH-LEVEL RADIOACTIVE WASTES IN A GEOLOGIC REPOSITORY AT YUCCA MOUNTAIN, NEVADA Postclosure Public Health and Environmental Standards § 63.304 Reasonable expectation. Reasonable expectation means...

  5. Interpersonal Expectancy Effects: A Forty Year Perspective.

    ERIC Educational Resources Information Center

    Rosenthal, Robert

    Interpersonal expectancy effects--the unintentional expectations that experimenters, teachers, and authority figures bring to experiments, classrooms, and other situations--can wield significant influence on individuals. Some of the issues surrounding expectancy effects are detailed in this paper. The effect itself has been recreated in

  6. 7 CFR 760.636 - Expected revenue.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 7 2011-01-01 2011-01-01 false Expected revenue. 760.636 Section 760.636 Agriculture... SPECIAL PROGRAMS INDEMNITY PAYMENT PROGRAMS Supplemental Revenue Assistance Payments Program § 760.636 Expected revenue. The expected revenue for each crop on a farm is: (a) For each insurable crop,...

  7. 7 CFR 760.636 - Expected revenue.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Expected revenue. 760.636 Section 760.636 Agriculture... SPECIAL PROGRAMS INDEMNITY PAYMENT PROGRAMS Supplemental Revenue Assistance Payments Program § 760.636 Expected revenue. The expected revenue for each crop on a farm is: (a) For each insurable crop,...

  8. Siting Samplers to Minimize Expected Time to Detection

    SciTech Connect

    Walter, Travis; Lorenzetti, David M.; Sohn, Michael D.

    2012-05-02

    We present a probabilistic approach to designing an indoor sampler network for detecting an accidental or intentional chemical or biological release, and demonstrate it for a real building. In an earlier paper, Sohn and Lorenzetti(1) developed a proof of concept algorithm that assumed samplers could return measurements only slowly (on the order of hours). This led to optimal detect to treat architectures, which maximize the probability of detecting a release. This paper develops a more general approach, and applies it to samplers that can return measurements relatively quickly (in minutes). This leads to optimal detect to warn architectures, which minimize the expected time to detection. Using a model of a real, large, commercial building, we demonstrate the approach by optimizing networks against uncertain release locations, source terms, and sampler characteristics. Finally, we speculate on rules of thumb for general sampler placement.

  9. Maximizing Your Investment in Building Automation System Technology.

    ERIC Educational Resources Information Center

    Darnell, Charles

    2001-01-01

    Discusses how organizational issues and system standardization can be important factors that determine an institution's ability to fully exploit contemporary building automation systems (BAS). Further presented is management strategy for maximizing BAS investments. (GR)

  10. Sensitivity to conversational maxims in deaf and hearing children.

    PubMed

    Surian, Luca; Tedoldi, Mariantonia; Siegal, Michael

    2010-09-01

    We investigated whether access to a sign language affects the development of pragmatic competence in three groups of deaf children aged 6 to 11 years: native signers from deaf families receiving bimodal/bilingual instruction, native signers from deaf families receiving oralist instruction and late signers from hearing families receiving oralist instruction. The performance of these children was compared to a group of hearing children aged 6 to 7 years on a test designed to assess sensitivity to violations of conversational maxims. Native signers with bimodal/bilingual instruction were as able as the hearing children to detect violations that concern truthfulness (Maxim of Quality) and relevance (Maxim of Relation). On items involving these maxims, they outperformed both the late signers and native signers attending oralist schools. These results dovetail with previous findings on mindreading in deaf children and underscore the role of early conversational experience and instructional setting in the development of pragmatics. PMID:19719886

  11. Carnot cycle at finite power: attainability of maximal efficiency.

    PubMed

    Allahverdyan, Armen E; Hovhannisyan, Karen V; Melkikh, Alexey V; Gevorkian, Sasun G

    2013-08-01

    We want to understand whether and to what extent the maximal (Carnot) efficiency for heat engines can be reached at a finite power. To this end we generalize the Carnot cycle so that it is not restricted to slow processes. We show that for realistic (i.e., not purposefully designed) engine-bath interactions, the work-optimal engine performing the generalized cycle close to the maximal efficiency has a long cycle time and hence vanishing power. This aspect is shown to relate to the theory of computational complexity. A physical manifestation of the same effect is Levinthal's paradox in the protein folding problem. The resolution of this paradox for realistic proteins allows to construct engines that can extract at a finite power 40% of the maximally possible work reaching 90% of the maximal efficiency. For purposefully designed engine-bath interactions, the Carnot efficiency is achievable at a large power. PMID:23952379

  12. Local distinguishability of maximally entangled states in canonical form

    NASA Astrophysics Data System (ADS)

    Zhang, Zhi-Chao; Gao, Fei; Qin, Su-Juan; Zuo, Hui-Juan; Wen, Qiao-Yan

    2015-10-01

    In this paper, we mainly study the local distinguishability of mutually orthogonal maximally entangled states in canonical form. In d ? d, Nathanson (Phys Rev A 88:062316, 2013) presented a feasible necessary and sufficient condition for distinguishing the general bipartite quantum states by one-way local operations and classical communication (LOCC). However, for maximally entangled states in canonical form, it is still unknown how to more effectively judge whether there exists a state such that those unitary operators corresponding to those maximally entangled states are pairwise orthogonal. In this work, we exhibit one method which can be used to more effectively judge it. Furthermore, we construct some sets of maximally entangled states and can easily know that those states are not distinguished by one-way LOCC with the help of our new method.

  13. The Maximization of Teacher Assignment: A Linear Programming Model

    ERIC Educational Resources Information Center

    Berrie, Phillip J.

    1974-01-01

    This study attempted to maximize the effectiveness of the teaching force through a successful assignment of teachers by considering the individual needs, competencies, and preferences of teachers and administrative staff, and selected student and curriculum factors. (Author)

  14. Maximal slicing of D-dimensional spherically symmetric vacuum spacetime

    SciTech Connect

    Nakao, Ken-ichi; Abe, Hiroyuki; Yoshino, Hirotaka; Shibata, Masaru

    2009-10-15

    We study the foliation of a D-dimensional spherically symmetric black-hole spacetime with D{>=}5 by two kinds of one-parameter families of maximal hypersurfaces: a reflection-symmetric foliation with respect to the wormhole slot and a stationary foliation that has an infinitely long trumpetlike shape. As in the four-dimensional case, the foliations by the maximal hypersurfaces avoid the singularity irrespective of the dimensionality. This indicates that the maximal slicing condition will be useful for simulating higher-dimensional black-hole spacetimes in numerical relativity. For the case of D=5, we present analytic solutions of the intrinsic metric, the extrinsic curvature, the lapse function, and the shift vector for the foliation by the stationary maximal hypersurfaces. These data will be useful for checking five-dimensional numerical-relativity codes based on the moving puncture approach.

  15. The maximization of overall reinforcement rate on concurrent chains.

    PubMed

    Houston, A I; Sumida, B H; McNamara, J M

    1987-07-01

    We model behavioral allocation on concurrent chains in which the initial links are independent variable-interval schedules. We also quantify the relationship between behavior during the initial links and the probability of entering a terminal link. The behavior that maximizes overall reinforcement rate is then considered and compared with published experimental data. Although all the trends in the data are predicted by rate maximization, there are considerable deviations from the predictions of rate maximization when reward magnitudes are unequal. We argue from our results that optimal allocation on concurrent chains, and prey choice as used in the theory of optimal diets, are distinct concepts. We show that the maximization of overall rate can lead to apparent violations of stochastic transitivity. PMID:16812485

  16. Suboptimal provision of preventive healthcare due to expected enrollee turnover among private insurers.

    PubMed

    Herring, Bradley

    2010-04-01

    Many preventive healthcare procedures are widely recognized as cost-effective but have relatively low utilization rates in the US. Because preventive care is a present-period investment with a future-period expected financial return, enrollee turnover among private insurers lowers the expected return of this investment. In this paper, I present a simple theoretical model to illustrate the suboptimal provision of preventive healthcare that results from insurers 'free riding' off of the provision from others. I also provide an empirical test of this hypothesis using data from the Community Tracking Study's Household Survey. I use lagged market-level measures of employment-induced insurer turnover to identify variation in insurers' expectations and test for the effect of turnover on several different measures of medical utilization. As expected, I find that turnover has a significantly negative effect on the utilization of preventive services and has no effect on the utilization of acute services used as a control. PMID:19353530

  17. A New Augmentation Based Algorithm for Extracting Maximal Chordal Subgraphs

    PubMed Central

    Bhowmick, Sanjukta; Chen, Tzu-Yi; Halappanavar, Mahantesh

    2014-01-01

    A graph is chordal if every cycle of length greater than three contains an edge between non-adjacent vertices. Chordal graphs are of interest both theoretically, since they admit polynomial time solutions to a range of NP-hard graph problems, and practically, since they arise in many applications including sparse linear algebra, computer vision, and computational biology. A maximal chordal subgraph is a chordal subgraph that is not a proper subgraph of any other chordal subgraph. Existing algorithms for computing maximal chordal subgraphs depend on dynamically ordering the vertices, which is an inherently sequential process and therefore limits the algorithms parallelizability. In this paper we explore techniques to develop a scalable parallel algorithm for extracting a maximal chordal subgraph. We demonstrate that an earlier attempt at developing a parallel algorithm may induce a non-optimal vertex ordering and is therefore not guaranteed to terminate with a maximal chordal subgraph. We then give a new algorithm that first computes and then repeatedly augments a spanning chordal subgraph. After proving that the algorithm terminates with a maximal chordal subgraph, we then demonstrate that this algorithm is more amenable to parallelization and that the parallel version also terminates with a maximal chordal subgraph. That said, the complexity of the new algorithm is higher than that of the previous parallel algorithm, although the earlier algorithm computes a chordal subgraph which is not guaranteed to be maximal. We experimented with our augmentation-based algorithm on both synthetic and real-world graphs. We provide scalability results and also explore the effect of different choices for the initial spanning chordal subgraph on both the running time and on the number of edges in the maximal chordal subgraph. PMID:25767331

  18. A new augmentation based algorithm for extracting maximal chordal subgraphs

    SciTech Connect

    Bhowmick, Sanjukta; Chen, Tzu-Yi; Halappanavar, Mahantesh

    2015-02-01

    A graph is chordal if every cycle of length greater than three contains an edge between non-adjacent vertices. Chordal graphs are of interest both theoretically, since they admit polynomial time solutions to a range of NP-hard graph problems, and practically, since they arise in many applications including sparse linear algebra, computer vision, and computational biology. A maximal chordal subgraph is a chordal subgraph that is not a proper subgraph of any other chordal subgraph. Existing algorithms for computing maximal chordal subgraphs depend on dynamically ordering the vertices, which is an inherently sequential process and therefore limits the algorithms’ parallelizability. In this paper we explore techniques to develop a scalable parallel algorithm for extracting a maximal chordal subgraph. We demonstrate that an earlier attempt at developing a parallel algorithm may induce a non-optimal vertex ordering and is therefore not guaranteed to terminate with a maximal chordal subgraph. We then give a new algorithm that first computes and then repeatedly augments a spanning chordal subgraph. After proving that the algorithm terminates with a maximal chordal subgraph, we then demonstrate that this algorithm is more amenable to parallelization and that the parallel version also terminates with a maximal chordal subgraph. That said, the complexity of the new algorithm is higher than that of the previous parallel algorithm, although the earlier algorithm computes a chordal subgraph which is not guaranteed to be maximal. We experimented with our augmentation-based algorithm on both synthetic and real-world graphs. We provide scalability results and also explore the effect of different choices for the initial spanning chordal subgraph on both the running time and on the number of edges in the maximal chordal subgraph.

  19. Lithium-thionyl chloride battery design concepts for maximized power applications

    NASA Astrophysics Data System (ADS)

    Kane, P.; Marincic, N.

    The need for primary batteries configured to deliver maximized power has been asserted by many different procuring activities. Battery Engineering Inc. has developed some specific design concepts and mastered some specialized techniques utilized in the production of this type of power source. The batteries have been successfully bench tested during the course of virtually all of these programs, with ultimate success coming in the form of two successful test launches under the USAF Plasma Effects Decoy Program. This paper briefly discusses some of these design concepts and the rationale behind them.

  20. Enumerating all maximal frequent subtrees in collections of phylogenetic trees

    PubMed Central

    2014-01-01

    Background A common problem in phylogenetic analysis is to identify frequent patterns in a collection of phylogenetic trees. The goal is, roughly, to find a subset of the species (taxa) on which all or some significant subset of the trees agree. One popular method to do so is through maximum agreement subtrees (MASTs). MASTs are also used, among other things, as a metric for comparing phylogenetic trees, computing congruence indices and to identify horizontal gene transfer events. Results We give algorithms and experimental results for two approaches to identify common patterns in a collection of phylogenetic trees, one based on agreement subtrees, called maximal agreement subtrees, the other on frequent subtrees, called maximal frequent subtrees. These approaches can return subtrees on larger sets of taxa than MASTs, and can reveal new common phylogenetic relationships not present in either MASTs or the majority rule tree (a popular consensus method). Our current implementation is available on the web at https://code.google.com/p/mfst-miner/. Conclusions Our computational results confirm that maximal agreement subtrees and all maximal frequent subtrees can reveal a more complete phylogenetic picture of the common patterns in collections of phylogenetic trees than maximum agreement subtrees; they are also often more resolved than the majority rule tree. Further, our experiments show that enumerating maximal frequent subtrees is considerably more practical than enumerating ordinary (not necessarily maximal) frequent subtrees. PMID:25061474

  1. Maximizing the detection of near-Earth objects

    NASA Astrophysics Data System (ADS)

    Albin, T.; Albrecht, S.; Koschny, D.; Drolshagen, G.

    2014-07-01

    Planetary bodies with a perihelion equal or less than 1.3 astronomical units (au) are called near-Earth objects (NEOs). These objects are divided into 4 sub-families, two of them cross Earth's orbit and may be a potential hazard for the planet. The Tunguska event and the incident in Chelyabinsk last year have shown the devastating destructiveness of NEOs with a size of only approximately 40 and 20 meters, respectively. To predict and identify further threats, telescopic NEO surveys currently extend our knowledge of the population of these objects. Today (March 2014) approximately 10,700 NEOs are known. Based on an extrapolation of the current population, Bottke et al. (2002) predict a total number of N≈(1.0±0.5)×10^{8} NEOs up to an absolute magnitude of H = 30.5 mag. Additionally, Bottke et al. (2002) computed a de-biased model of the expected orbital elements distribution of the NEOs. They have investigated the theoretical distribution of NEOs by a dynamical simulation, following the orbital evolution of these objects from several source regions. Based on both models we performed simulations of the detectability of the theoretical NEO population for certain telescopes with certain properties. The goal of these simulations is to optimize the search strategies of NEO surveys. Our simulation models the optical telescope attributes (main and secondary mirror size, optical throughput, field-of-view), the electronics (CCD Camera, pixel size, quantum efficiency, gain, exposure time, pixel binning, dark / bias noise, Signal-to-Noise ratio), atmospheric effects (seeing, sky background illumination) and the brightness and angular velocity of the NEOs. We present exemplarily results for two telescopes, currently developed by the European Space Agency for a future NEO survey: the so-called Fly-Eye Telescope, a 1-m effective aperture telescope with a field of view of 6.5×6.5 deg^2 and the Test-Bed Telescope, with an aperture of 56 cm and a field of view of 2.2×2.2 deg^2. The results of both telescopes can be easily adapted to other telescopes with similar properties. We show different observation strategies to maximize the detection rate of undiscovered NEOs depending on different telescope operation modes (exposure time, pixel binning) and different sky conditions (seeing, sky background brightness).

  2. Does Explicit Expectation Really Affect Preparation?

    PubMed Central

    Umbach, Valentin J.; Schwager, Sabine; Frensch, Peter A.; Gaschler, Robert

    2012-01-01

    Expectation enables preparation for an upcoming event and supports performance if the anticipated situation occurs, as manifested in behavioral effects (e.g., decreased RT). However, demonstrating coincidence between expectation and preparation is not sufficient for attributing a causal role to the former. The content of explicit expectation may simply reflect the present preparation state. We targeted this issue by experimentally teasing apart demands for preparation and explicit expectations. Expectations often originate from our experience: we expect that events occurring with a high frequency in the past are more likely to occur again. In addition to expectation, other task demands can feed into action preparation. In four experiments, frequency-based expectation was pitted against a selective response deadline. In a three-choice reaction time task, participants responded to stimuli that appeared with varying frequency (60, 30, 10%). Trial-by-trial stimulus expectations were either captured via verbal predictions or induced by visual cues. Predictions as well as response times quickly conformed to the variation in stimulus frequency. After two (of five) experimental blocks we forced participants by selective time pressure to respond faster to a less frequent stimulus. Therefore, participants had to prepare for one stimulus (medium frequency) while often explicitly expecting a different one (high frequency). Response times for the less frequent stimulus decreased immediately, while explicit expectations continued to indicate the (unchanged) presentation frequencies. Explicit expectations were thus not just reflecting preparation. In fact, participants responded faster when the stimulus matched the trial-wise expectations, even when task demands discouraged their use. In conclusion, we argue that explicit expectation feeds into preparatory processes instead of being a mere by-product. PMID:23248606

  3. STOCK MARKET CRASH AND EXPECTATIONS OF AMERICAN HOUSEHOLDS.

    PubMed

    Hudomiet, Pter; Kzdi, Gbor; Willis, Robert J

    2011-01-01

    This paper utilizes data on subjective probabilities to study the impact of the stock market crash of 2008 on households' expectations about the returns on the stock market index. We use data from the Health and Retirement Study that was fielded in February 2008 through February 2009. The effect of the crash is identified from the date of the interview, which is shown to be exogenous to previous stock market expectations. We estimate the effect of the crash on the population average of expected returns, the population average of the uncertainty about returns (subjective standard deviation), and the cross-sectional heterogeneity in expected returns (disagreement). We show estimates from simple reduced-form regressions on probability answers as well as from a more structural model that focuses on the parameters of interest and separates survey noise from relevant heterogeneity. We find a temporary increase in the population average of expectations and uncertainty right after the crash. The effect on cross-sectional heterogeneity is more significant and longer lasting, which implies substantial long-term increase in disagreement. The increase in disagreement is larger among the stockholders, the more informed, and those with higher cognitive capacity, and disagreement co-moves with trading volume and volatility in the market. PMID:21547244

  4. STOCK MARKET CRASH AND EXPECTATIONS OF AMERICAN HOUSEHOLDS*

    PubMed Central

    HUDOMIET, PÉTER; KÉZDI, GÁBOR; WILLIS, ROBERT J.

    2011-01-01

    SUMMARY This paper utilizes data on subjective probabilities to study the impact of the stock market crash of 2008 on households’ expectations about the returns on the stock market index. We use data from the Health and Retirement Study that was fielded in February 2008 through February 2009. The effect of the crash is identified from the date of the interview, which is shown to be exogenous to previous stock market expectations. We estimate the effect of the crash on the population average of expected returns, the population average of the uncertainty about returns (subjective standard deviation), and the cross-sectional heterogeneity in expected returns (disagreement). We show estimates from simple reduced-form regressions on probability answers as well as from a more structural model that focuses on the parameters of interest and separates survey noise from relevant heterogeneity. We find a temporary increase in the population average of expectations and uncertainty right after the crash. The effect on cross-sectional heterogeneity is more significant and longer lasting, which implies substantial long-term increase in disagreement. The increase in disagreement is larger among the stockholders, the more informed, and those with higher cognitive capacity, and disagreement co-moves with trading volume and volatility in the market. PMID:21547244

  5. Violated expectancies: Cause and function of exploration, fear, and aggression.

    PubMed

    van Kampen, Hendrik S

    2015-08-01

    To be able to reproduce, animals need to survive and interact with an ever changing environment. Therefore, they create a cognitive representation of that environment, from which they derive expectancies regarding current and future events. These expected events are compared continuously with information gathered through exploration, to guide behaviour and update the existing representation. When a moderate discrepancy between perceived and expected events is detected, exploration is employed to update the internal representation so as to alter the expectancy and make it match the perceived event. When the discrepancy is relatively large, exploration is inhibited, and animals will try to alter the perceived event utilizing aggression or fear. The largest discrepancies are associated with a tendency to flee. When an exploratory, fear, or aggressive behaviour pattern proofs to be the optimal solution for a particular discrepancy, the response will become conditioned to events that previously preceded the occurrence of that discrepancy. When primary needs are relatively low, animals will actively look for or create moderately violated expectancies in order to learn about objects, behaviour patterns, and the environment. In those situations, exploratory tendencies will summate with ongoing behaviour and, when all primary needs are satiated, may even be performed exclusively. This results in behavioural variability, play, and active information-seeking. This article is part of a Special Issue entitled: In Honor of Jerry Hogan. PMID:24878517

  6. Design and manufacturing rules for maximizing the performance of polycrystalline piezoelectric bending actuators

    NASA Astrophysics Data System (ADS)

    Jafferis, Noah T.; Smith, Michael J.; Wood, Robert J.

    2015-06-01

    Increasing the energy and power density of piezoelectric actuators is very important for any weight-sensitive application, and is especially crucial for enabling autonomy in micro/milli-scale robots and devices utilizing this technology. This is achieved by maximizing the mechanical flexural strength and electrical dielectric strength through the use of laser-induced melting or polishing, insulating edge coating, and crack-arresting features, combined with features for rigid ground attachments to maximize force output. Manufacturing techniques have also been developed to enable mass customization, in which sheets of material are pre-stacked to form a laminate from which nearly arbitrary planar actuator designs can be fabricated using only laser cutting. These techniques have led to a 70% increase in energy density and an increase in mean lifetime of at least 15× compared to prior manufacturing methods. In addition, measurements have revealed a doubling of the piezoelectric coefficient when operating at the high fields necessary to achieve maximal energy densities, along with an increase in the Young’s modulus at the high compressive strains encountered—these two effects help to explain the higher performance of our actuators as compared to that predicted by linear models.

  7. Moving multiple sinks through wireless sensor networks for lifetime maximization.

    SciTech Connect

    Petrioli, Chiara; Carosi, Alessio; Basagni, Stefano; Phillips, Cynthia Ann

    2008-01-01

    Unattended sensor networks typically watch for some phenomena such as volcanic events, forest fires, pollution, or movements in animal populations. Sensors report to a collection point periodically or when they observe reportable events. When sensors are too far from the collection point to communicate directly, other sensors relay messages for them. If the collection point location is static, sensor nodes that are closer to the collection point relay far more messages than those on the periphery. Assuming all sensor nodes have roughly the same capabilities, those with high relay burden experience battery failure much faster than the rest of the network. However, since their death disconnects the live nodes from the collection point, the whole network is then dead. We consider the problem of moving a set of collectors (sinks) through a wireless sensor network to balance the energy used for relaying messages, maximizing the lifetime of the network. We show how to compute an upper bound on the lifetime for any instance using linear and integer programming. We present a centralized heuristic that produces sink movement schedules that produce network lifetimes within 1.4% of the upper bound for realistic settings. We also present a distributed heuristic that produces lifetimes at most 25:3% below the upper bound. More specifically, we formulate a linear program (LP) that is a relaxation of the scheduling problem. The variables are naturally continuous, but the LP relaxes some constraints. The LP has an exponential number of constraints, but we can satisfy them all by enforcing only a polynomial number using a separation algorithm. This separation algorithm is a p-median facility location problem, which we can solve efficiently in practice for huge instances using integer programming technology. This LP selects a set of good sensor configurations. Given the solution to the LP, we can find a feasible schedule by selecting a subset of these configurations, ordering them via a traveling salesman heuristic, and computing feasible transitions using matching algorithms. This algorithm assumes sinks can get a schedule from a central server or a leader sink. If the network owner prefers the sinks make independent decisions, they can use our distributed heuristic. In this heuristic, sinks maintain estimates of the energy distribution in the network and move greedily (with some coordination) based on local search. This application uses the new SUCASA (Solver Utility for Customization with Automatic Symbol Access) facility within the PICO (Parallel Integer and Combinatorial Optimizer) integer programming solver system. SUCASA allows rapid development of customized math programming (search-based) solvers using a problem's natural multidimensional representation. In this case, SUCASA also significantly improves runtime compared to implementations in the ampl math programming language or in perl.

  8. How fast-growing bacteria robustly tune their ribosome concentration to approximate growth-rate maximization

    PubMed Central

    Bosdriesz, Evert; Molenaar, Douwe; Teusink, Bas; Bruggeman, Frank J

    2015-01-01

    Maximization of growth rate is an important fitness strategy for bacteria. Bacteria can achieve this by expressing proteins at optimal concentrations, such that resources are not wasted. This is exemplified for Escherichia coli by the increase of its ribosomal protein-fraction with growth rate, which precisely matches the increased protein synthesis demand. These findings and others have led to the hypothesis that E. coli aims to maximize its growth rate in environments that support growth. However, what kind of regulatory strategy is required for a robust, optimal adjustment of the ribosome concentration to the prevailing condition is still an open question. In the present study, we analyze the ppGpp-controlled mechanism of ribosome expression used by E. coli and show that this mechanism maintains the ribosomes saturated with its substrates. In this manner, overexpression of the highly abundant ribosomal proteins is prevented, and limited resources can be redirected to the synthesis of other growth-promoting enzymes. It turns out that the kinetic conditions for robust, optimal protein-partitioning, which are required for growth rate maximization across conditions, can be achieved with basic biochemical interactions. We show that inactive ribosomes are the most suitable ‘signal’ for tracking the intracellular nutritional state and for adjusting gene expression accordingly, as small deviations from optimal ribosome concentration cause a huge fractional change in ribosome inactivity. We expect to find this control logic implemented across fast-growing microbial species because growth rate maximization is a common selective pressure, ribosomes are typically highly abundant and thus costly, and the required control can be implemented by a small, simple network. PMID:25754869

  9. How fast-growing bacteria robustly tune their ribosome concentration to approximate growth-rate maximization.

    PubMed

    Bosdriesz, Evert; Molenaar, Douwe; Teusink, Bas; Bruggeman, Frank J

    2015-05-01

    Maximization of growth rate is an important fitness strategy for bacteria. Bacteria can achieve this by expressing proteins at optimal concentrations, such that resources are not wasted. This is exemplified for Escherichia coli by the increase of its ribosomal protein-fraction with growth rate, which precisely matches the increased protein synthesis demand. These findings and others have led to the hypothesis that E. coli aims to maximize its growth rate in environments that support growth. However, what kind of regulatory strategy is required for a robust, optimal adjustment of the ribosome concentration to the prevailing condition is still an open question. In the present study, we analyze the ppGpp-controlled mechanism of ribosome expression used by E. coli and show that this mechanism maintains the ribosomes saturated with its substrates. In this manner, overexpression of the highly abundant ribosomal proteins is prevented, and limited resources can be redirected to the synthesis of other growth-promoting enzymes. It turns out that the kinetic conditions for robust, optimal protein-partitioning, which are required for growth rate maximization across conditions, can be achieved with basic biochemical interactions. We show that inactive ribosomes are the most suitable 'signal' for tracking the intracellular nutritional state and for adjusting gene expression accordingly, as small deviations from optimal ribosome concentration cause a huge fractional change in ribosome inactivity. We expect to find this control logic implemented across fast-growing microbial species because growth rate maximization is a common selective pressure, ribosomes are typically highly abundant and thus costly, and the required control can be implemented by a small, simple network. PMID:25754869

  10. Premenstrual symptoms and smoking-related expectancies.

    PubMed

    Pang, Raina D; Bello, Mariel S; Stone, Matthew D; Kirkpatrick, Matthew G; Huh, Jimi; Monterosso, John; Haselton, Martie G; Fales, Melissa R; Leventhal, Adam M

    2016-06-01

    Given that prior research implicates smoking abstinence in increased premenstrual symptoms, tobacco withdrawal, and smoking behaviors, it is possible that women with more severe premenstrual symptoms have stronger expectancies about the effects of smoking and abstaining from smoking on mood and withdrawal. However, such relations have not been previously explored. This study examined relations between premenstrual symptoms experienced in the last month and expectancies that abstaining from smoking results in withdrawal (i.e., smoking abstinence withdrawal expectancies), that smoking is pleasurable (i.e., positive reinforcement smoking expectancies), and smoking relieves negative mood (i.e., negative reinforcement smoking expectancies). In a cross-sectional design, 97 non-treatment seeking women daily smokers completed self-report measures of smoking reinforcement expectancies, smoking abstinence withdrawal expectancies, premenstrual symptoms, mood symptoms, and nicotine dependence. Affect premenstrual symptoms were associated with increased negative reinforcement smoking expectancies, but not over and above covariates. Affect and pain premenstrual symptoms were associated with increased positive reinforcement smoking expectancies, but only affect premenstrual symptoms remained significant in adjusted models. Affect, pain, and water retention premenstrual symptoms were associated with increased smoking abstinence withdrawal expectancies, but only affect premenstrual symptoms remained significant in adjusted models. Findings from this study suggest that addressing concerns about withdrawal and alternatives to smoking may be particularly important in women who experience more severe premenstrual symptoms, especially affect-related changes. PMID:26869196

  11. Women's Retirement Expectations: How Stable Are They?

    PubMed Central

    Hardy, Melissa A.

    2009-01-01

    Objective Using the National Longitudinal Survey of Mature Women, we examine between- and within-person differences in expected retirement age as a key element of the retirement planning process. The expectation typologies of 1,626 women born between 1923 and 1937 were classified jointly on the basis of specificity and consistency. Methods Latent class analysis was used to determine retirement expectation patterns over a 7-year span. Multinomial logistic regression analyses were employed to estimate the effects of demographic and status characteristics on the likelihood of reporting 4 distinct longitudinal patterns of retirement expectations. Results Substantial heterogeneity in reports of expected retirement age between and within individuals over the 7-year span was found. Demographic and status characteristics, specifically age, race, marital status, job tenure, and recent job change, sorted respondents into different retirement expectation patterns. Conclusions The frequent within-person fluctuations and substantial between-person heterogeneity in retirement expectations indicate uncertainty and variability in both expectations and process of expectation formation. Variability in respondents' reports suggests that studying retirement expectations at multiple time points better captures the dynamics of preretirement planning. PMID:19176483

  12. Combustion Research Aboard the ISS Utilizing the Combustion Integrated Rack and Microgravity Science Glovebox

    NASA Technical Reports Server (NTRS)

    Sutliff, Thomas J.; Otero, Angel M.; Urban, David L.

    2002-01-01

    The Physical Sciences Research Program of NASA sponsors a broad suite of peer-reviewed research investigating fundamental combustion phenomena and applied combustion research topics. This research is performed through both ground-based and on-orbit research capabilities. The International Space Station (ISS) and two facilities, the Combustion Integrated Rack and the Microgravity Science Glovebox, are key elements in the execution of microgravity combustion flight research planned for the foreseeable future. This paper reviews the Microgravity Combustion Science research planned for the International Space Station implemented from 2003 through 2012. Examples of selected research topics, expected outcomes, and potential benefits will be provided. This paper also summarizes a multi-user hardware development approach, recapping the progress made in preparing these research hardware systems. Within the description of this approach, an operational strategy is presented that illustrates how utilization of constrained ISS resources may be maximized dynamically to increase science through design decisions made during hardware development.

  13. Transient hovering performance of hummingbirds under conditions of maximal loading.

    PubMed

    Chai, P; Chen, J S; Dudley, R

    1997-03-01

    Maximal load-lifting capacities of six ruby-throated hummingbirds (Archilochus colubris) were determined under conditions of burst performance. Mechanical power output under maximal loading was then compared with maximal hovering performance in hypodense gas mixtures of normodense air and heliox. The maximal load lifted was similar at air temperatures of 5 and 25 degrees C, and averaged 80% of body mass. The duration of load-lifting was brief, of the order of 1 s, and was probably sustained via phosphagen substrates. Under maximal loading, estimates of muscle mass-specific mechanical power output assuming perfect elastic energy storage averaged 206 W kg-1, compared with 94 W kg-1 during free hovering without loading. Under conditions of limiting performance in hypodense mixtures, maximal mechanical power output was much lower (131 W kg-1, five birds) but was sustained for longer (4 s), demonstrating an inverse relationship between the magnitude and duration of maximum power output. In free hovering flight, stroke amplitude and wingbeat frequency varied in inverse proportion between 5 and 25 degrees C, suggesting thermoregulatory contributions by the flight muscles. Stroke amplitude under conditions of maximal loading reached a geometrical limit at slightly greater than 180 degrees. Previous studies of maximum performance in flying animals have estimated mechanical power output using a simplified actuator disk model without a detailed knowledge of wingbeat frequency and stroke amplitude. The present load-lifting results, together with actuator disc estimates of induced power derived from hypodense heliox experiments, are congruent with previous load-lifting studies of maximum flight performance. For ruby-throated hummingbirds, the inclusion of wingbeat frequency and stroke amplitude in a more detailed aerodynamic model of hovering yields values of mechanical power output 34% higher than previous estimates. More generally, the study of performance limits in flying animals necessitates careful specification of behavioral context as well as quantitative determination of wing and body kinematics. PMID:9100364

  14. Muscle function in men and women during maximal eccentric exercise.

    PubMed

    Hubal, Monica J; Rubinstein, Scott R; Clarkson, Priscilla M

    2008-07-01

    This study assessed muscle fatigue patterns of the elbow flexors in untrained men and women to determine if sex differences exist during acute maximal eccentric exercise. High-intensity eccentric exercise is often used by athletes to elicit gains in muscle strength and size gains. Development of fatigue during this type of exercise can increase risk of injury; therefore, it is important to understand fatigue patterns during eccentric exercise to minimize injury risk exposure while still promoting training effects. While many isometric exercise studies have demonstrated that women show less fatigue, the patterns of fatigue during purely eccentric exercise have not been assessed in men and women. Based on the lack of sex differences in overall strength loss immediately post-eccentric exercise, it was hypothesized that women and men would have similar relative fatigue pattern responses (i.e., change from baseline) during a single bout of maximal eccentric exercise. Forty-six subjects (24 women and 22 men) completed 5 sets of 10 maximal eccentric contractions on an isokinetic dynamometer. Maximal voluntary isometric contraction strength was assessed at baseline and immediately following each exercise set. Maximal eccentric torque and contractile properties (i.e., contraction time, work, half relaxation time, and maximal rate of torque development) were calculated for each contraction. Men and women demonstrated similar relative isometric (32% for men and 39% for women) and eccentric (32% for men and 39% for women) fatigue as well as similar deficits in work done and rates of torque development and relaxation during exercise (p > 0.05). Untrained men and women displayed similar relative responses in all measures of muscle function during a single bout of maximal eccentric exercise of the elbow flexors. Thus, there is no reason to suspect that women may be more vulnerable to fatigue-related injury. PMID:18545170

  15. Stock Market Expectations of Dutch Households

    PubMed Central

    Hurd, Michael; van Rooij, Maarten; Winter, Joachim

    2013-01-01

    Despite its importance for the analysis of life-cycle behavior and, in particular, retirement planning, stock ownership by private households is poorly understood. Among other approaches to investigate this puzzle, recent research has started to elicit private households expectations of stock market returns. This paper reports findings from a study that collected data over a two-year period both on households stock market expectations (subjective probabilities of gains or losses) and on whether they own stocks. We document substantial heterogeneity in financial market expectations. Expectations are correlated with stock ownership. Over the two years of our data, stock market prices increased, and expectations of future stock market price changes also increased, lending support to the view that expectations are influenced by recent stock gains or losses. PMID:23997423

  16. Integrated life sciences technology utilization development program

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The goal of the TU program was to maximize the development of operable hardware and systems which will be of substantial benefit to the public. Five working prototypes were developed, and a meal system for the elderly is now undergoing evaluation. Manpower utilization is shown relative to the volume of requests in work for each month. The ASTP mobile laboratories and post Skylab bedrest study are also described.

  17. Great Expectations. What the President Expects of the PR Director and What You Should Expect in Return.

    ERIC Educational Resources Information Center

    Fisher, James L.

    1980-01-01

    A college president has a right to expect competence, loyalty, knowledge of the president, sensitivity, new ideas, contingency plans, a knowledge of higher education, effective management, partisanship, and hard work from his/her public relations officer. In return, that officer should expect respect, support, reward, and status in decision…

  18. Ventilatory patterns differ between maximal running and cycling.

    PubMed

    Tanner, David A; Duke, Joseph W; Stager, Joel M

    2014-01-15

    To determine the effect of exercise mode on ventilatory patterns, 22 trained men performed two maximal graded exercise tests; one running on a treadmill and one cycling on an ergometer. Tidal flow-volume (FV) loops were recorded during each minute of exercise with maximal loops measured pre and post exercise. Running resulted in a greater VO2peak than cycling (62.77.6 vs. 58.17.2mLkg(-1)min(-1)). Although maximal ventilation (VE) did not differ between modes, ventilatory equivalents for O2 and CO2 were significantly larger during maximal cycling. Arterial oxygen saturation (estimated via ear oximeter) was also greater during maximal cycling, as were end-expiratory (EELV; 3.400.54 vs. 3.210.55L) and end-inspiratory lung volumes, (EILV; 6.240.88 vs. 5.900.74L). Based on these results we conclude that ventilatory patterns differ as a function of exercise mode and these observed differences are likely due to the differences in posture adopted during exercise in these modes. PMID:24211317

  19. Maximizing Output Power in a Cantilevered Piezoelectric Vibration Energy Harvester by Electrode Design

    NASA Astrophysics Data System (ADS)

    Du, Sijun; Jia, Yu; Seshia, Ashwin

    2015-12-01

    A resonant vibration energy harvester typically comprises of a clamped anchor and a vibrating shuttle with a proof mass. Piezoelectric materials are embedded in locations of high strain in order to transduce mechanical deformation into electric charge. Conventional design for piezoelectric vibration energy harvesters (PVEH) usually utilizes piezoelectric material and metal electrode layers covering the entire surface area of the cantilever with no consideration provided to examining the trade-off involved with respect to maximizing output power. This paper reports on the theory and experimental verification underpinning optimization of the active electrode area of a cantilevered PVEH in order to maximize output power. The analytical formulation utilizes Euler-Bernoulli beam theory to model the mechanical response of the cantilever. The expression for output power is reduced to a fifth order polynomial expression as a function of the electrode area. The maximum output power corresponds to the case when 44% area of the cantilever is covered by electrode metal. Experimental results are also provided to verify the theory.

  20. Bioengineering and Coordination of Regulatory Networks and Intracellular Complexes to Maximize Hydrogen Production by Phototrophic Microorganisms

    SciTech Connect

    Tabita, F. Robert

    2013-07-30

    In this study, the Principal Investigator, F.R. Tabita has teemed up with J. C. Liao from UCLA. This project's main goal is to manipulate regulatory networks in phototrophic bacteria to affect and maximize the production of large amounts of hydrogen gas under conditions where wild-type organisms are constrained by inherent regulatory mechanisms from allowing this to occur. Unrestrained production of hydrogen has been achieved and this will allow for the potential utilization of waste materials as a feed stock to support hydrogen production. By further understanding the means by which regulatory networks interact, this study will seek to maximize the ability of currently available “unrestrained” organisms to produce hydrogen. The organisms to be utilized in this study, phototrophic microorganisms, in particular nonsulfur purple (NSP) bacteria, catalyze many significant processes including the assimilation of carbon dioxide into organic carbon, nitrogen fixation, sulfur oxidation, aromatic acid degradation, and hydrogen oxidation/evolution. Moreover, due to their great metabolic versatility, such organisms highly regulate these processes in the cell and since virtually all such capabilities are dispensable, excellent experimental systems to study aspects of molecular control and biochemistry/physiology are available.

  1. Predicting Problem Behaviors with Multiple Expectancies: Expanding Expectancy-Value Theory

    ERIC Educational Resources Information Center

    Borders, Ashley; Earleywine, Mitchell; Huey, Stanley J.

    2004-01-01

    Expectancy-value theory emphasizes the importance of outcome expectancies for behavioral decisions, but most tests of the theory focus on a single behavior and a single expectancy. However, the matching law suggests that individuals consider expected outcomes for both the target behavior and alternative behaviors when making decisions. In this

  2. Matching and maximizing with variable-time schedules.

    PubMed Central

    DeCarlo, L T

    1985-01-01

    Pigeons were offered choices between a variable-time schedule that arranged reinforcers throughout the session and a variable-time schedule that arranged reinforcers only when the pigeon was spending time on it. The subjects could maximize the overall rate of reinforcement in this situation by biasing their time allocation towards the latter schedule. This arrangement provides an alternative to concurrent variable-interval variable-ratio schedules for testing whether animals maximize overall rates or match relative rates, and has the advantage of being free of the asymmetrical response requirements present with those schedules. The results were contrary to those predicted by maximizing: The bias it predicts did not appear. PMID:3981085

  3. Cardiovascular consequences of bed rest: effect on maximal oxygen uptake

    NASA Technical Reports Server (NTRS)

    Convertino, V. A.

    1997-01-01

    Maximal oxygen uptake (VO2max) is reduced in healthy individuals confined to bed rest, suggesting it is independent of any disease state. The magnitude of reduction in VO2max is dependent on duration of bed rest and the initial level of aerobic fitness (VO2max), but it appears to be independent of age or gender. Bed rest induces an elevated maximal heart rate which, in turn, is associated with decreased cardiac vagal tone, increased sympathetic catecholamine secretion, and greater cardiac beta-receptor sensitivity. Despite the elevation in heart rate, VO2max is reduced primarily from decreased maximal stroke volume and cardiac output. An elevated ejection fraction during exercise following bed rest suggests that the lower stroke volume is not caused by ventricular dysfunction but is primarily the result of decreased venous return associated with lower circulating blood volume, reduced central venous pressure, and higher venous compliance in the lower extremities. VO2max, stroke volume, and cardiac output are further compromised by exercise in the upright posture. The contribution of hypovolemia to reduced cardiac output during exercise following bed rest is supported by the close relationship between the relative magnitude (% delta) and time course of change in blood volume and VO2max during bed rest, and also by the fact that retention of plasma volume is associated with maintenance of VO2max after bed rest. Arteriovenous oxygen difference during maximal exercise is not altered by bed rest, suggesting that peripheral mechanisms may not contribute significantly to the decreased VO2max. However reduction in baseline and maximal muscle blood flow, red blood cell volume, and capillarization in working muscles represent peripheral mechanisms that may contribute to limited oxygen delivery and, subsequently, lowered VO2max. Thus, alterations in cardiac and vascular functions induced by prolonged confinement to bed rest contribute to diminution of maximal oxygen uptake and reserve capacity to perform physical work.

  4. Do Students Expect Compensation for Wage Risk?

    ERIC Educational Resources Information Center

    Schweri, Juerg; Hartog, Joop; Wolter, Stefan C.

    2011-01-01

    We use a unique data set about the wage distribution that Swiss students expect for themselves ex ante, deriving parametric and non-parametric measures to capture expected wage risk. These wage risk measures are unfettered by heterogeneity which handicapped the use of actual market wage dispersion as risk measure in earlier studies. Students in

  5. Cognitive Processing and Expectancy Behavior in Hypnosis

    ERIC Educational Resources Information Center

    Dolby, Robyn M.; Sheehan, Peter W.

    1977-01-01

    Two independent studies were conducted to examine the expectancy behavior of unselected hypnotic, task-motivated, and control-imagination subjects on a slide task requiring response to ambiguous visual information. Results showed that hypnotic subjects consistently demonstrated expectancy behavior, whereas nonhypnotic subjects did not. (Editor/RK)

  6. Trends in Life Expectancy in Wellbeing

    ERIC Educational Resources Information Center

    Perenboom, R. J. M.; Van Herten, L. M.; Boshuizen, H. C.; Van Den Bos, G. A. M.

    2004-01-01

    Objectives: This paper describes and discusses trends in life expectancy in wellbeing between 1989 and 1998. Methods: Data on wellbeing by the Bradburn Affect Balance Scale is obtained from the Netherlands Continuous Health Interview Surveys for the calendar years from 1989 to 1998. Using Sullivan's method, life expectancy in wellbeing is…

  7. Using Daily Horoscopes To Demonstrate Expectancy Confirmation.

    ERIC Educational Resources Information Center

    Munro, Geoffrey D.; Munro, James E.

    2000-01-01

    Describes a classroom demonstration that uses daily horoscopes to show the effect that expectation can have on judgment. Addresses the preparation, procedure, and results of the demonstration, and student evaluations. States that the demonstration appears to be effective for teaching students about expectancy confirmation. (CMK)

  8. Teacher and Parent Expectations for Kindergarten Readiness.

    ERIC Educational Resources Information Center

    Welch, Michael D.; White, Barzanna

    Based upon the view that children learn better if their parents' and teachers' expectations are closely aligned, this study compared expectations of teachers and parents for school readiness skills and preparation required for entry into public school. A Likert rating scale was completed by 25 kindergarten/early childhood teachers and 104 parents…

  9. Teaching Rational Expectations at 'A' Level.

    ERIC Educational Resources Information Center

    Beachill, Bob

    1987-01-01

    Explains the economic concept of Rational Expectations (RE) and demonstrates how it can be introduced to British 'A' level students. Illustrates the implications of RE for the Cobweb and Augmented Phillips Curve market models. Outlines some attractions and limitations of rational expectations. (Author/DH)

  10. Dissonant Feedback about Achievement and Teachers' Expectations.

    ERIC Educational Resources Information Center

    Bognar, Carl J.

    1982-01-01

    Investigates impact of achievement test results (N=285) on 13 sixth-grade teachers' expectations using hypotheses from cognitive dissonance theory. Shows teacher expectations changed very little as a result of feedback, and test results for both under- and overestimated students were rejected. (AH)

  11. What Respondents Really Expect from Researchers

    ERIC Educational Resources Information Center

    Kolar, Tomaz; Kolar, Iztok

    2008-01-01

    This article addresses the issue of falling response rates in telephone surveys. To better understand and maintain respondent goodwill, concepts of psychological contract and respondent expectations are introduced and explored. Results of the qualitative study show that respondent expectations are not only socially contingent but also

  12. Rising Tides: Faculty Expectations of Library Websites

    ERIC Educational Resources Information Center

    Nicol, Erica Carlson; O'English, Mark

    2012-01-01

    Looking at 2003-2009 LibQUAL+ responses at research-oriented universities in the United States, faculty library users report a significant and consistent rise in desires and expectations for library-provided online tools and websites, even as student user groups show declining or leveling expectations. While faculty, like students, also report…

  13. The Expectant Reader in Theory and Practice.

    ERIC Educational Resources Information Center

    Fowler, Lois Josephs; McCormick, Kathleen

    1986-01-01

    Offers a method of using reader response theory that emphasizes the expectations about a text and how those expectations are fulfilled or deflated. Specifically, students read traditional fables, fairy tales, and parables, and compare them to contemporary works such as Kafka's "Metamorphosis" and Marquez's "The Very Old Man With Enormous Wings."

  14. International Variations in Measuring Customer Expectations.

    ERIC Educational Resources Information Center

    Calvert, Philip J.

    2001-01-01

    Discussion of customer expectations of library service quality and SERVQUAL as a measurement tool focuses on two studies: one that compared a survey of Chinese university students' expectations of service quality to New Zealand students; and one that investigated national culture as a source of attitudes to customer service. (Author/LRW)

  15. Teacher Expectations and the Able Child.

    ERIC Educational Resources Information Center

    Lee-Corbin, Hilary

    1994-01-01

    Two middle school teachers and two students in each of the teacher's classes were assessed for field dependence-independence (FDI). The teachers were interviewed about their students. Found that one teacher had higher expectations and one had lower expectations for the student who had the same FDI orientation as the teacher than for the student

  16. Grief Experiences and Expectance of Suicide

    ERIC Educational Resources Information Center

    Wojtkowiak, Joanna; Wild, Verena; Egger, Jos

    2012-01-01

    Suicide is generally viewed as an unexpected cause of death. However, some suicides might be expected to a certain extent, which needs to be further studied. The relationships between expecting suicide, feeling understanding for the suicide, and later grief experiences were explored. In total, 142 bereaved participants completed the Grief

  17. 47 CFR 90.743 - Renewal expectancy.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Renewal expectancy. 90.743 Section 90.743 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Regulations Governing Licensing and Use of Frequencies in the 220-222 MHz Band 90.743 Renewal expectancy. (a)...

  18. 47 CFR 90.743 - Renewal expectancy.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Renewal expectancy. 90.743 Section 90.743 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Regulations Governing Licensing and Use of Frequencies in the 220-222 MHz Band 90.743 Renewal expectancy. (a)...

  19. Raising Expectations is Aim of New Effort

    ERIC Educational Resources Information Center

    Sparks, Sarah D.

    2010-01-01

    Researchers and policymakers agree that teachers' expectations of what their students can do can become self-fulfilling prophecies for children's academic performance. Yet while the "soft bigotry of low expectations" has become an education catchphrase, scholars and advocates are just beginning to explore whether it is possible to prevent such

  20. Rising Tides: Faculty Expectations of Library Websites

    ERIC Educational Resources Information Center

    Nicol, Erica Carlson; O'English, Mark

    2012-01-01

    Looking at 2003-2009 LibQUAL+ responses at research-oriented universities in the United States, faculty library users report a significant and consistent rise in desires and expectations for library-provided online tools and websites, even as student user groups show declining or leveling expectations. While faculty, like students, also report

  1. Parents' Role in Adolescents' Educational Expectations

    ERIC Educational Resources Information Center

    Rimkute, Laura; Hirvonen, Riikka; Tolvanen, Asko; Aunola, Kaisa; Nurmi, Jari-Erik

    2012-01-01

    The present study examined the extent to which mothers' and fathers' expectations for their offspring's future education, their level of education, and adolescents' academic achievement predict adolescents' educational expectations. To investigate this, 230 adolescents were examined twice while they were in comprehensive school (in the 7th and 9th…

  2. Determination of the maximal fat oxidation point in obese children and adolescents: validity of methods to assess maximal aerobic power.

    PubMed

    Aucouturier, Julien; Rance, Mlanie; Meyer, Martine; Isacco, Laurie; Thivel, David; Fellmann, Nicole; Duclos, Martine; Duch, Pascale

    2009-01-01

    We aimed to examine the interchangeability of techniques used to assess maximal oxygen consumption (VO2max) and maximal aerobic power (MAP) employed to express the maximal fat oxidation point in obese children and adolescents. Rate of fat oxidation were measured in 24 obese subjects (13.0 +/- 2.4 years; Body Mass Index 30.2 +/- 6.3 kg m(-2)) who performed a five 4-min stages submaximal incremental cycling exercise. A second cycling exercise was performed to measure VO2max. Results are those of the 20 children who achieved the criterion of RER (>1.02) to assess the attainment of VO2max. Although correlations between results obtained by different methods were strong, Bland-Altman plots showed little agreement between the maximal fat oxidation point expressed as a percentage of measured VO2max and as % VO2max estimated according to ACSM guidelines (underestimation : -5.9%) or using the predictive equations of Wasserman (-13.9%). Despite a mean underestimation of 1.4% several values were out of the limits of agreement when comparing measured MAP and Theoretical MAP. Estimations of VO2max lead to underestimations of the maximal fat oxidation point. PMID:19002708

  3. Maximizing the Divergence from a Hierarchical Model of Quantum States

    NASA Astrophysics Data System (ADS)

    Weis, Stephan; Knauf, Andreas; Ay, Nihat; Zhao, Ming-Jing

    2015-03-01

    We study many-party correlations quantified in terms of the Umegaki relative entropy (divergence) from a Gibbs family known as a hierarchical model. We derive these quantities from the maximum-entropy principle which was used earlier to define the closely related irreducible correlation. We point out the differences between quantum states and probability vectors which exist in hierarchical models, in the divergence from a hierarchical model and in local maximizers of this divergence. The differences are, respectively, missing factorization, discontinuity and reduction of uncertainty. We discuss global maximizers of the mutual information of separable qubit states.

  4. Maximal expiratory flow volume curve in quarry workers.

    PubMed

    Subhashini, Arcot Sadagopa; Satchidhanandam, Natesa

    2002-01-01

    Maximal Expiratory Flow Volume (MEFV) curves were recorded with a computerized Spirometer (Med Spiror). Forced Vital Capacity (FVC), Forced Expiratory Volumes (FEV), mean and maximal flow rates were obtained in 25 quarry workers who were free from respiratory disorders and 20 healthy control subjects. All the functional values are lower in quarry workers than in the control subject, the largest reduction in quarry workers with a work duration of over 15 years, especially for FEF75. The effects are probably due to smoking rather than dust exposure. PMID:12024961

  5. Projection of two biphoton qutrits onto a maximally entangled state.

    PubMed

    Halevy, A; Megidish, E; Shacham, T; Dovrat, L; Eisenberg, H S

    2011-04-01

    Bell state measurements, in which two quantum bits are projected onto a maximally entangled state, are an essential component of quantum information science. We propose and experimentally demonstrate the projection of two quantum systems with three states (qutrits) onto a generalized maximally entangled state. Each qutrit is represented by the polarization of a pair of indistinguishable photons-a biphoton. The projection is a joint measurement on both biphotons using standard linear optics elements. This demonstration enables the realization of quantum information protocols with qutrits, such as teleportation and entanglement swapping. PMID:21517363

  6. Expectancy set, self-reported expectancies and predispositional traits: predicting interest in violence and erotica.

    PubMed

    George, W H; Dermen, K H; Nochajski, T H

    1989-11-01

    To investigate the role of alcohol expectancies in predicting postdrinking behavior, two studies were conducted. In Study 1, an instrument assessing alcohol expectancies was devised for later use in prediction. Factor analyses with split-sample validation confirmed 3 factors (11 total items): disinhibition, aggression and sexuality. In Study 2, expectancies, Buss-Durkee hostility and Mosher sex-guilt were assessed in a preexperimental questionnaire session. In a subsequent drink administration session, an expectancy set manipulation led subjects to expect alcohol or to expect tonic. To assess postdrinking behavior, interest in violent, erotic and violent-erotic materials was measured unobtrusively using an ad lib slide-viewing task. Consistent with the hypotheses, expectancies in conjunction with trait hostility significantly predicted violence viewing and violent-erotica viewing for expect alcohol, but not expect tonic controls. Moreover, after variance due to hostility was accounted for, expectancies predicted violence viewing significantly and violent-erotica viewing marginally. These findings provide modest support for the proposition that preexisting alcohol expectancies mediate between the effects of expectancy set and postdrinking behaviors. Once activated by perceived alcohol ingestion, these expectancies can shape postdrinking behaviors. The findings also underscore the need for further experimentation aimed at clarifying the interrelationships between alcohol expectancies and expectancy set. PMID:2586107

  7. Bison distribution under conflicting foraging strategies: site fidelity vs. energy maximization.

    PubMed

    Merkle, Jerod A; Cherry, Seth G; Fortin, Daniel

    2015-07-01

    Foraging strategies based on site fidelity and maximization of energy intake rate are two adaptive forces shaping animal behavior. Whereas these strategies can both be evolutionarily stable, they predict conflicting optimal behaviors when population abundance is in decline. In such a case, foragers employing an energy-maximizing strategy should reduce their use of low-quality patches as interference competition becomes less intense for high-quality patches. Foragers using a site fidelity strategy, however, should continue to use familiar patches. Because natural fluctuations in population abundance provide the only non-manipulative opportunity to evaluate adaptation to these evolutionary forces, few studies have examined these foraging strategies simultaneously. Using abundance and space use data from a free-ranging bison (Bison bison) population living in a meadow-forest matrix in Prince Albert National Park, Canada, we determined how individuals balance the trade-off between site fidelity and energy-maximizing patch choice strategies with respect to changes in population abundance. From 1996 to 2005, bison abundance increased from 225 to 475 and then decreased to 225 by 2013. During the period of population increase, population range size increased. This expansion involved the addition of relatively less profitable areas and patches, leading to a decrease in the mean expected profitability of the range. Yet, during the period of population decline, we detected neither a subsequent retraction in population range size nor an increase in mean expected profitability of the range. Further, patch selection models. during the population decline indicated that, as density decreased, bison portrayed stronger fidelity to previously visited meadows, but no increase in selection strength for profitable meadows. Our analysis reveals that an energy-maximizing patch choice strategy alone cannot explain the distribution ofindividuals and populations, and site fidelity is an important evolutionary force shaping animal distribution. Animals may not always forage in the richest patches available, as ecological theory would often predict, but their use of profitable patches is dependent on population dynamics and the strength of site fidelity. Our findings are likewise relevant to applied inquiries such as forecasting species range shifts and reducing human-wildlife conflicts. PMID:26378302

  8. Different types of compression clothing do not increase sub-maximal and maximal endurance performance in well-trained athletes.

    PubMed

    Sperlich, Billy; Haegele, Matthias; Achtzehn, Silvia; Linville, John; Holmberg, Hans-Christer; Mester, Joachim

    2010-04-01

    Three textiles with increasing compressive surface were compared with non-compressive conventional clothing on physiological and perceptual variables during sub-maximal and maximal running. Fifteen well-trained endurance athletes (mean+/-s: age 27.1+/-4.8 years, VO(2max) 63.7+/-4.9 ml x min(-1) x kg(-1)) performed four sub-maximal (approximately 70% VO(2max)) and maximal tests with and without different compression stockings, tights, and whole-body compression suits. Arterial lactate concentration, oxygen saturation and partial pressure, pH, oxygen uptake, and ratings of muscle soreness were recorded before, during, and after all tests. In addition, we assessed time to exhaustion. Sub-maximal (P=0.22) and maximal oxygen uptake (P=0.26), arterial lactate concentration (P=0.16; 0.20), pH (P=0.23; 0.46), oxygen saturation (P=0.13; 0.26), and oxygen partial pressure (P=0.09; 0.20) did not differ between the types of clothing (effect sizes=0.00-0.45). Ratings of perceived exertion (P=0.10; 0.15), muscle soreness (P=0.09; 0.10) and time to exhaustion (P=0.16) were also unaffected by the different clothing (effect sizes=0.28-0.85). This was the first study to evaluate the effect on endurance performance of different types of compression clothing with increasing amounts of compressive surface. Overall, there were no performance benefits when using the compression garments. PMID:20391083

  9. Expected degree for RNA secondary structure networks.

    PubMed

    Clote, Peter

    2015-01-15

    Consider the network of all secondary structures of a given RNA sequence, where nodes are connected when the corresponding structures have base pair distance one. The expected degree of the network is the average number of neighbors, where average may be computed with respect to the either the uniform or Boltzmann probability. Here, we describe the first algorithm, RNAexpNumNbors, that can compute the expected number of neighbors, or expected network degree, of an input sequence. For RNA sequences from the Rfam database, the expected degree is significantly less than the constrained minimum free energy structure, defined to have minimum free energy (MFE) over all structures consistent with the Rfam consensus structure. The expected degree of structural RNAs, such as purine riboswitches, paradoxically appears to be smaller than that of random RNA, yet the difference between the degree of the MFE structure and the expected degree is larger than that of random RNA. Expected degree does not seem to correlate with standard structural diversity measures of RNA, such as positional entropy and ensemble defect. The program RNAexpNumNbors is written in C, runs in cubic time and quadratic space, and is publicly available at http://bioinformatics.bc.edu/clotelab/RNAexpNumNbors. PMID:25382310

  10. Impact of psychotherapist expectations on client outcomes.

    PubMed

    Connor, Dana R; Callahan, Jennifer L

    2015-09-01

    Recent investigations have implicated client expectations of psychotherapy as a strong predictor of premature termination; however, there is reason to believe psychotherapist expectations may also impact client outcomes. This study sought to address this gap in the literature by examining the association of psychotherapists' expectations to clients' psychotherapy outcomes, including termination status. Participants were 54 current and recent trainee psychotherapists at a Southern public university, who completed delay discounting measures to assess their expectations of the effectiveness of psychotherapy. Data were also drawn from 300 adult clients who had received at least 2 sessions of individual psychotherapy from the participating psychotherapists of this study, and had previously completed the Outcome Questionnaire 45.2 prior to each individual therapy session. Psychotherapists were found to hold significantly higher expectations for client improvement than anticipated, based on existing literature, and these high expectations were found to be positively correlated with clinically significant change in clients. Moreover, psychotherapists' expectations were found to explain 7.3% of the explainable variance in whether or not clients experienced clinically significant change during psychotherapy. Implications for improving client retention and treatment outcome are discussed. PMID:25961371

  11. Neurobiology of placebo effects: expectations or learning?

    PubMed

    Pecia, Marta; Stohler, Christian S; Zubieta, Jon-Kar

    2014-07-01

    Contemporary learning theories suggest that conditioning is heavily dependent on the processing of prediction errors, which signal a discrepancy between expected and observed outcomes. This line of research provides a framework through which classical theories of placebo effects, expectations and conditioning, can be reconciled. Brain regions related to prediction error processing [anterior cingulate cortex (ACC), orbitofrontal cortex or the nucleus accumbens] overlap with those involved in placebo effects. Here we examined the possibility that the magnitude of objective neurochemical responses to placebo administration would depend on individual expectation-effectiveness comparisons. We show that such comparisons and not expectations per se predict behavioral placebo responses and placebo-induced activation of -opioid receptor-mediated neurotransmission in regions relevant to error detection (e.g. ACC). Expectations on the other hand were associated with greater -opioid system activation in the dorsolateral prefrontal cortex but not with greater behavioral placebo responses. The results presented aid the elucidation of molecular and neural mechanisms underlying the relationship between expectation-effectiveness associations and the formation of placebo responses, shedding light on the individual differences in learning and decision making. Expectation and outcome comparisons emerge as a cognitive mechanism that beyond reward associations appears to facilitate the formation and sustainability of placebo responses. PMID:23887819

  12. Expectations predict chronic pain treatment outcomes.

    PubMed

    Cormier, Stphanie; Lavigne, Genevive L; Choinire, Manon; Rainville, Pierre

    2016-02-01

    Accumulating evidence suggests an association between patient pretreatment expectations and numerous health outcomes. However, it remains unclear if and how expectations relate to outcomes after treatments in multidisciplinary pain programs. The present study aims at investigating the predictive association between expectations and clinical outcomes in a large database of chronic pain patients. In this observational cohort study, participants were 2272 patients treated in one of 3 university-affiliated multidisciplinary pain treatment centers. All patients received personalized care, including medical, psychological, and/or physical interventions. Patient expectations regarding pain relief and improvements in quality of life and functioning were measured before the first visit to the pain centers and served as predictor variables. Changes in pain intensity, depressive symptoms, pain interference, and tendency to catastrophize, as well as satisfaction with pain treatment and global impressions of change at 6-month follow-up, were considered as treatment outcomes. Structural equation modeling analyses showed significant positive relationships between expectations and most clinical outcomes, and this association was largely mediated by patients' global impressions of change. Similar patterns of relationships between variables were also observed in various subgroups of patients based on sex, age, pain duration, and pain classification. Such results emphasize the relevance of patient expectations as a determinant of outcomes in multimodal pain treatment programs. Furthermore, the results suggest that superior clinical outcomes are observed in individuals who expect high positive outcomes as a result of treatment. PMID:26447703

  13. Modifying Softball for Maximizing Learning Outcomes in Physical Education

    ERIC Educational Resources Information Center

    Brian, Ali; Ward, Phillip; Goodway, Jacqueline D.; Sutherland, Sue

    2014-01-01

    Softball is taught in many physical education programs throughout the United States. This article describes modifications that maximize learning outcomes and that address the National Standards and safety recommendations. The modifications focus on tasks and equipment, developmentally appropriate motor-skill acquisition, increasing number of

  14. Maximizing the Benefits of an Administrative Internship: Some Practical Advice.

    ERIC Educational Resources Information Center

    Oldfield, Kenneth; Ayers, Nancy

    Recommendations to help student interns in administrative positions maximize their educational opportunities vis-a-vis the "real world" and to also help them avoid certain placement-associated problems. The suggestions may be helpful to both new and established internship directors as well. Attention is focused on governmental administrative

  15. Respiratory mechanics and breathing pattern during and following maximal exercise.

    PubMed

    Younes, M; Kivinen, G

    1984-12-01

    We looked for evidence of changes in lung elastic recoil and of inspiratory muscle fatigue at maximal exercise in seven normal subjects. Esophageal pressure, flow, and volume were measured during spontaneous breathing at increasing levels of cycle exercise to maximum. Total lung capacity (TLC) was determined at rest and immediately before exercise termination using a N2-washout technique. Maximal inspiratory pressure and inspiratory capacity were measured at 1-min intervals. The time course of instantaneous dynamic pressure of respiratory muscles (Pmus) was calculated for the spontaneous breaths immediately preceding exercise termination. TLC volume and lung elastic recoil at TLC were the same at the end of exercise as at rest. Maximum static inspiratory pressures at exercise termination were not reduced. However, mean Pmus of spontaneous breaths at end exercise exceeded 15% of maximum inspiratory pressure in five of the subjects. We conclude that lung elastic recoil is unchanged even at maximal exercise and that, while inspiratory muscles operate within a potentially fatiguing range, the high levels of ventilation observed during maximal exercise are not maintained for a sufficient time to result in mechanical fatigue. PMID:6511552

  16. The Profit-Maximizing Firm: Old Wine in New Bottles.

    ERIC Educational Resources Information Center

    Felder, Joseph

    1990-01-01

    Explains and illustrates a simplified use of graphical analysis for analyzing the profit-maximizing firm. Believes that graphical analysis helps college students gain a deeper understanding of marginalism and an increased ability to formulate economic problems in marginalist terms. (DB)

  17. Emotional Control and Instructional Effectiveness: Maximizing a Timeout

    ERIC Educational Resources Information Center

    Andrews, Staci R.

    2015-01-01

    This article provides recommendations for best practices for basketball coaches to maximize the instructional effectiveness of a timeout during competition. Practical applications are derived from research findings linking emotional intelligence to effective coaching behaviors. Additionally, recommendations are based on the implications of the…

  18. On Maximal Subalgebras and the Hypercentre of Lie Algebras.

    ERIC Educational Resources Information Center

    Honda, Masanobu

    1997-01-01

    Derives two sufficient conditions for a finitely generated Lie algebra to have the nilpotent hypercenter. Presents a relatively large class of generalized soluble Lie algebras. Proves that if a finitely generated Lie algebra has a nilpotent maximal subalgebra, the Fitting radical is nilpotent. (DDR)

  19. On Adaptation, Maximization, and Reinforcement Learning among Cognitive Strategies

    ERIC Educational Resources Information Center

    Erev, Ido; Barron, Greg

    2005-01-01

    Analysis of binary choice behavior in iterated tasks with immediate feedback reveals robust deviations from maximization that can be described as indications of 3 effects: (a) a payoff variability effect, in which high payoff variability seems to move choice behavior toward random choice; (b) underweighting of rare events, in which alternatives

  20. Emotional Control and Instructional Effectiveness: Maximizing a Timeout

    ERIC Educational Resources Information Center

    Andrews, Staci R.

    2015-01-01

    This article provides recommendations for best practices for basketball coaches to maximize the instructional effectiveness of a timeout during competition. Practical applications are derived from research findings linking emotional intelligence to effective coaching behaviors. Additionally, recommendations are based on the implications of the

  1. Modifying Softball for Maximizing Learning Outcomes in Physical Education

    ERIC Educational Resources Information Center

    Brian, Ali; Ward, Phillip; Goodway, Jacqueline D.; Sutherland, Sue

    2014-01-01

    Softball is taught in many physical education programs throughout the United States. This article describes modifications that maximize learning outcomes and that address the National Standards and safety recommendations. The modifications focus on tasks and equipment, developmentally appropriate motor-skill acquisition, increasing number of…

  2. Teacher Praise: Maximizing the Motivational Impact. Teaching Strategies.

    ERIC Educational Resources Information Center

    McVey, Mary D.

    2001-01-01

    Recognizes the influence of praise on human behavior, and provides specific suggestions on how to maximize the positive effects of praise when intended as positive reinforcement. Examines contingency, specificity, and selectivity aspects of praise. Cautions teachers to avoid the controlling effects of praise and the possibility that praise may

  3. Maximizing plant density affects broccoli yield and quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increased demand for fresh market bunch broccoli (Brassica oleracea L. var. italica) has led to increased production along the United States east coast. Maximizing broccoli yields is a primary concern for quickly expanding southeastern commercial markets. This broccoli plant density study was carr...

  4. Inquiry Pedagogy: Maximizing Literacy Learning and Teaching through Shared Inquiry.

    ERIC Educational Resources Information Center

    Peck, Jacqueline K.; Hughes, Sharon V.

    A study examined one first-grade teacher's use of inquiry pedagogy to maximize literacy learning and teaching in her classroom. The setting for the study was a classroom in the Cleveland, Ohio, School District. In this classroom literacy events build upon students' prior knowledge and experience gleaned from their lives outside the classroom and…

  5. Optimal technique for maximal forward rotating vaults in men's gymnastics.

    PubMed

    Hiley, Michael J; Jackson, Monique I; Yeadon, Maurice R

    2015-08-01

    In vaulting a gymnast must generate sufficient linear and angular momentum during the approach and table contact to complete the rotational requirements in the post-flight phase. This study investigated the optimization of table touchdown conditions and table contact technique for the maximization of rotation potential for forwards rotating vaults. A planar seven-segment torque-driven computer simulation model of the contact phase in vaulting was evaluated by varying joint torque activation time histories to match three performances of a handspring double somersault vault by an elite gymnast. The closest matching simulation was used as a starting point to maximize post-flight rotation potential (the product of angular momentum and flight time) for a forwards rotating vault. It was found that the maximized rotation potential was sufficient to produce a handspring double piked somersault vault. The corresponding optimal touchdown configuration exhibited hip flexion in contrast to the hyperextended configuration required for maximal height. Increasing touchdown velocity and angular momentum lead to additional post-flight rotation potential. By increasing the horizontal velocity at table touchdown, within limits obtained from recorded performances, the handspring double somersault tucked with one and a half twists, and the handspring triple somersault tucked became theoretically possible. PMID:26026290

  6. Effect of Eleutherococcus senticosus on submaximal and maximal exercise performance.

    PubMed

    Dowling, E A; Redondo, D R; Branch, J D; Jones, S; McNabb, G; Williams, M H

    1996-04-01

    We investigated the effect of Eleutherococcus senticosus Maxim L (ESML) on performance during submaximal and maximal aerobic exercise. Twenty highly trained distance runners randomly assigned in matched pairs to either an experimental (ESML) or placebo (PL) group, participated in an 8-wk double-blind study during which they completed five trails of a 10-min treadmill run at their 10 km (10K) race pace and a maximal treadmill test (T(max)). Following a baseline trail, ESML and PL consumed, respectively, 3.4 ml of ESML extract or placebo daily for 6 wk. Subjects were tested every 2 wk during supplementation and 2 wk following withdrawal. Heart rate (HR), oxygen consumption (VO2), expired minute volume (VE), ventilatory equivalent for oxygen (VE/VO2), respiratory exchange ratio (RER), and rating of perceived exertion (RPE) were measured during the 10K and T(max) tests. Resting, post-10K and post-T(max) blood samples were analyzed for serum lactate. No significant differences were observed between ESML and PL for: HR, VO2, VE, VE/VO2, RER, or RPE; T(max) time to exhaustion; or serum lactate. The data do not support an ergogenic effect of ESML supplementation on selected metabolic, performance, or psychologic parameters associated with submaximal and maximal aerobic exercise tasks. PMID:8778554

  7. Maximizing Thermal Efficiency and Optimizing Energy Management (Fact Sheet)

    SciTech Connect

    Not Available

    2012-03-01

    Researchers at the Thermal Test Facility (TTF) on the campus of the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) in Golden, Colorado, are addressing maximizing thermal efficiency and optimizing energy management through analysis of efficient heating, ventilating, and air conditioning (HVAC) strategies, automated home energy management (AHEM), and energy storage systems.

  8. Maximality and Idealized Cognitive Models: The Complementation of Spanish "Tener."

    ERIC Educational Resources Information Center

    Hilferty, Joseph; Valenzuela, Javier

    2001-01-01

    Discusses the bare-noun phrase (NP) complementation pattern of the Spanish verb "tener" (have). Shows that the maximality of the complement NP is dependent upon three factors: (1) idiosyncratic valence requirements; (2) encyclopedic knowledge related to possession; and (3) contextualized semantic construal. (Author/VWL)

  9. Bernoulli equation and the nonexistence of maximal jets

    NASA Astrophysics Data System (ADS)

    Zdziarski, Andrzej A.

    2016-02-01

    We discuss the idea of maximal jets introduced by Falcke & Biermann (1995, A&A, 293, 665). According to it, the maximum possible jet power in its internal energy equals the kinetic power in its rest mass. We show this result is incorrect because of an unfortunate algebraic mistake.

  10. Maximizing grain sorghum water use efficiency under deficit irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Development and evaluation of sustainable and efficient irrigation strategies is a priority for producers faced with water shortages resulting from aquifer depletion, reduced base flows, and reallocation of water to non-agricultural sectors. Under a limited water supply, yield maximization may not b...

  11. Nursing Students' Awareness and Intentional Maximization of Their Learning Styles

    ERIC Educational Resources Information Center

    Mayfield, Linda Riggs

    2012-01-01

    This small, descriptive, pilot study addressed survey data from four levels of nursing students who had been taught to maximize their learning styles in a first-semester freshman success skills course. Bandura's Agency Theory supports the design. The hypothesis was that without reinforcing instruction, the students' recall and application of that…

  12. An effective theory of metrics with maximal proper acceleration

    NASA Astrophysics Data System (ADS)

    Gallego Torromé, Ricardo

    2015-12-01

    A geometric theory for spacetimes whose world lines associated with physical particles have an upper bound for the proper acceleration is developed. After some fundamental remarks on the requirements that the classical dynamics for point particles should hold, the notion of a generalized metric and a theory of maximal proper acceleration are introduced. A perturbative approach to metrics of maximal proper acceleration is discussed and we show how it provides a consistent theory where the associated Lorentzian metric corresponds to the limit when the maximal proper acceleration goes to infinity. Then several of the physical and kinematical properties of the maximal acceleration metric are investigated, including a discussion of the rudiments of the causal theory and the introduction of the notions of radar distance and celerity function. We discuss the corresponding modification of the Einstein mass-energy relation when the associated Lorentzian geometry is flat. In such a context it is also proved that the physical dispersion relation is relativistic. Two possible physical scenarios where the modified mass-energy relation could be confronted against the experiment are briefly discussed.

  13. Predicted maximal heart rate for upper body exercise testing.

    PubMed

    Hill, M; Talbot, C; Price, M

    2016-03-01

    Age-predicted maximal heart rate (HRMAX ) equations are commonly used for the purpose of prescribing exercise regimens, as criteria for achieving maximal exertion and for diagnostic exercise testing. Despite the growing popularity of upper body exercise in both healthy and clinical settings, no recommendations are available for exercise modes using the smaller upper body muscle mass. The purpose of this study was to determine how well commonly used age-adjusted prediction equations for HRMAX estimate actual HRMAX for upper body exercise in healthy young and older adults. A total of 30 young (age: 20 ± 2 years, height: 171·9 ± 32·8 cm, mass: 77·7 ± 12·6 kg) and 20 elderly adults (age: 66 ± 6 years, height: 162 ± 8·1 cm, mass: 65·3 ± 12·3 kg) undertook maximal incremental exercise tests on a conventional arm crank ergometer. Age-adjusted maximal heart rate was calculated using prediction equations based on leg exercise and compared with measured HRMAX data for the arms. Maximal HR for arm exercise was significantly overpredicted compared with age-adjusted prediction equations in both young and older adults. Subtracting 10-20 beats min(-1) from conventional prediction equations provides a reasonable estimate of HRMAX for upper body exercise in healthy older and younger adults. PMID:25319169

  14. What To Expect Before a Lung Transplant

    MedlinePLUS

    ... NHLBI on Twitter. What To Expect Before a Lung Transplant If you get into a medical center's ... friends also can offer support. When a Donor Lung Becomes Available OPTN matches donor lungs to recipients ...

  15. What to Expect During a Lung Transplant

    MedlinePLUS

    ... NHLBI on Twitter. What To Expect During a Lung Transplant Just before lung transplant surgery, you will ... airway and its blood vessels to your heart. Lung Transplant The illustration shows the process of a ...

  16. Classics in the Classroom: Great Expectations Fulfilled.

    ERIC Educational Resources Information Center

    Pearl, Shela

    1986-01-01

    Describes how an English teacher in a Queens, New York, ghetto school introduced her grade nine students to Charles Dickens's "Great Expectations." Focuses on students' responses, which eventually became enthusiastic, and discusses the use of classics within the curriculum. (KH)

  17. Parental outcome expectations on children's TV viewing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Children's TV viewing has been associated with increased sedentary behavior and poor eating habits. Positive intervention effects have been observed when addressing outcome expectations as a mediator in interventions targeting children's dietary behavior. Little is known about parental outcome expec...

  18. What to Expect during a Heart Transplant

    MedlinePLUS

    ... on Twitter. What To Expect During a Heart Transplant Just before heart transplant surgery, the patient will ... not replaced as part of the surgery. Heart Transplant Figure A shows where the diseased heart is ...

  19. What to Expect during Heart Surgery

    MedlinePLUS

    ... the NHLBI on Twitter. What To Expect During Heart Surgery Heart surgery is done in a hospital, ... surgery, takes about 3–6 hours. Traditional Open-Heart Surgery For this type of surgery, you'll ...

  20. Comparison of myocardial /sup 201/Tl clearance after maximal and submaximal exercise: implications for diagnosis of coronary disease: concise communication

    SciTech Connect

    Massie, B.M.; Wisneski, J.; Kramer, B.; Hollenberg, M.; Gertz, E.; Stern, D.

    1982-05-01

    Recently the quantitation of regional /sup 201/Tl clearance has been shown to increase the sensitivity of the scintigraphic detection of coronary disease. Although /sup 201/Tl clearance rates might be expected to vary with the degree of exercise, this relationship has not been explored. We therefore evaluated the rate of decrease in myocardial /sup 201/Tl activity following maximal and submaximal stress in seven normal subjects and 21 patients with chest pain, using the seven-pinhole tomographic reconstruction technique. In normals, the mean /sup 201/Tl clearance rate declined from 41% +/- 7 over a 3-hr period with maximal exercise to 25% +/- 5 after 3 hr at a submaximal level (p less than 0.001). Similar differences in clearance rates were found in the normally perfused regions of the left ventricle in patients with chest pain, depending on whether or not a maximal end point (defined as either the appearance of ischemia or reaching 85% of age-predicted heart rate) was achieved. In five patients who did not reach these end points, 3-hr clearance rates in uninvolved regions averaged 25% +/- 2, in contrast to a mean of 38% +/- 5 for such regions in 15 patients who exercised to ischemia or an adequate heart rate. These findings indicate that clearance criteria derived from normals can be applied to patients who are stressed maximally, even if the duration of exercise is limited, but that caution must be used in interpreting clearance rates in those who do not exercise to an accepted end point.

  1. Measuring Student Expectations and Their Effects on Satisfaction: The Importance of Managing Student Expectations

    ERIC Educational Resources Information Center

    Appleton-Knapp, Sara L.; Krentler, Kathleen A.

    2006-01-01

    Two studies investigate the relationship between student expectations and student satisfaction. Can students' satisfaction with a course be accurately predicted by comparing their perceptions to their expectations (as suggested by the expectancy/disconfirmation paradigm)? The results of these studies suggest that the answer to this question is…

  2. Contributions of leaf photosynthetic capacity, leaf angle and self-shading to the maximization of net photosynthesis in Acer saccharum: a modelling assessment

    PubMed Central

    Posada, Juan M.; Sievnen, Risto; Messier, Christian; Perttunen, Jari; Nikinmaa, Eero; Lechowicz, Martin J.

    2012-01-01

    Background and Aims Plants are expected to maximize their net photosynthetic gains and efficiently use available resources, but the fundamental principles governing trade-offs in suites of traits related to resource-use optimization remain uncertain. This study investigated whether Acer saccharum (sugar maple) saplings could maximize their net photosynthetic gains through a combination of crown structure and foliar characteristics that let all leaves maximize their photosynthetic light-use efficiency (?). Methods A functionalstructural model, LIGNUM, was used to simulate individuals of different leaf area index (LAIind) together with a genetic algorithm to find distributions of leaf angle (LA) and leaf photosynthetic capacity (Amax) that maximized net carbon gain at the whole-plant level. Saplings grown in either the open or in a forest gap were simulated with Amax either unconstrained or constrained to an upper value consistent with reported values for Amax in A. saccharum. Key Results It was found that total net photosynthetic gain was highest when whole-plant PPFD absorption and leaf ? were simultaneously maximized. Maximization of ? required simultaneous adjustments in LA and Amax along gradients of PPFD in the plants. When Amax was constrained to a maximum, plants growing in the open maximized their PPFD absorption but not ? because PPFD incident on leaves was higher than the PPFD at which ?max was attainable. Average leaf ? in constrained plants nonetheless improved with increasing LAIind because of an increase in self-shading. Conclusions It is concluded that there are selective pressures for plants to simultaneously maximize both PPFD absorption at the scale of the whole individual and ? at the scale of leaves, which requires a highly integrated response between LA, Amax and LAIind. The results also suggest that to maximize ? plants have evolved mechanisms that co-ordinate the LA and Amax of individual leaves with PPFD availability. PMID:22665700

  3. Gamma loop contributing to maximal voluntary contractions in man.

    PubMed Central

    Hagbarth, K E; Kunesch, E J; Nordin, M; Schmidt, R; Wallin, E U

    1986-01-01

    A local anaesthetic drug was injected around the peroneal nerve in healthy subjects in order to investigate whether the resulting loss in foot dorsiflexion power in part depended on a gamma-fibre block preventing 'internal' activation of spindle end-organs and thereby depriving the alpha-motoneurones of an excitatory spindle inflow during contraction. The motor outcome of maximal dorsiflexion efforts was assessed by measuring firing rates of individual motor units in the anterior tibial (t.a.) muscle, mean voltage e.m.g. from the pretibial muscles, dorsiflexion force and range of voluntary foot dorsiflexion movements. The tests were performed with and without peripheral conditioning stimuli, such as agonist or antagonist muscle vibration or imposed stretch of the contracting muscles. As compared to control values of t.a. motor unit firing rates in maximal isometric voluntary contractions, the firing rates were lower and more irregular during maximal dorsiflexion efforts performed during subtotal peroneal nerve blocks. During the development of paresis a gradual reduction of motor unit firing rates was observed before the units ceased responding to the voluntary commands. This change in motor unit behaviour was accompanied by a reduction of the mean voltage e.m.g. activity in the pretibial muscles. At a given stage of anaesthesia the e.m.g. responses to maximal voluntary efforts were more affected than the responses evoked by electric nerve stimuli delivered proximal to the block, indicating that impaired impulse transmission in alpha motor fibres was not the sole cause of the paresis. The inability to generate high and regular motor unit firing rates during peroneal nerve blocks was accentuated by vibration applied over the antagonistic calf muscles. By contrast, in eight out of ten experiments agonist stretch or vibration caused an enhancement of motor unit firing during the maximal force tasks. The reverse effects of agonist and antagonist vibration on the ability to activate the paretic muscles were evidenced also by alterations induced in mean voltage e.m.g. activity, dorsiflexion force and range of dorsiflexion movements. The autogenetic excitatory and the reciprocal inhibitory effects of muscle vibration rose in strength as the vibration frequency was raised from 90 to 165 Hz. Reflex effects on maximal voluntary contraction strength similar to those observed during partial nerve blocks were not seen under normal conditions when the nerve supply was intact.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:3612576

  4. Epigallocatechin-3-gallate Increases Maximal Oxygen Uptake in Adult Humans

    PubMed Central

    Richards, Jennifer C.; Lonac, Mark C.; Johnson, Tyler K.; Schweder, Melani M.; Bell, Christopher

    2009-01-01

    Epigallocatechin-3-gallate (EGCG), a component of green tea, increases endurance performance in animals and promotes fat oxidation during cycle ergometer exercise in adult humans. Purpose We have investigated the hypothesis that short-term consumption of EGCG delays the onset of the ventilatory threshold (TVE) and increases maximal oxygen uptake (VO2max). Methods In this randomized, repeated measures, double blind study, 19 healthy adults (11 males, 8 females, age: 26 ± 2 years (mean ± SE)) received 7 placebo or 7 EGCG (135 mg) pills. 48-hours prior to data collection participants began consuming 3 pills per day; the last pill was taken 2-hours before exercise testing. TVE and VO2max were determined from breath-by-breath indirect calorimetry data collected during continuous incremental stationary cycle ergometer exercise (20-35 W/min), from rest until volitional fatigue. Each condition/exercise test was separated by a minimum of 14-days. Results Compared with placebo, short-term EGCG consumption increased VO2max (3.123 ± 0.187 vs. 3.259 ± 0.196 L·min-1, P=0.04). Maximal work rate (301 ± 15 vs. 301 ± 16 W, P=0.98), maximal respiratory exchange ratio (1.21 ± 0.01 vs. 1.22 ± 0.02, P=0.27), and maximal heart rate were unaffected (180 ± 3 vs. 180 ± 3 beats·min-1, P=0.87). In a subset of subjects (n=11) maximal cardiac output (determined via open-circuit acetylene breathing) was also unaffected by EGCG (29.6 ± 2.2 vs. 30.2 ± 1.4 L·min-1, P=0.70). Contrary to our hypothesis, EGCG decreased VO2 at TVE (1.57 ± 0.11 vs. 1.48 ± 0.10 L·min-1) but this change was not significant (P=0.06). Conclusion Short-term consumption of EGCG increased VO2max without affecting maximal cardiac output, suggesting that EGCG may increase arterial-venous oxygen difference. PMID:19952844

  5. Understanding the Hows and Whys of Decision-Making: From Expected Utility to Divisive Normalization.

    PubMed

    Glimcher, Paul

    2014-01-01

    Over the course of the last century, economists and ethologists have built detailed models from first principles of how humans and animals should make decisions. Over the course of the last few decades, psychologists and behavioral economists have gathered a wealth of data at variance with the predictions of these economic models. This has led to the development of highly descriptive models that can often predict what choices people or animals will make but without offering any insight into why people make the choices that they do--especially when those choices reduce a decision-maker's well-being. Over the course of the last two decades, neurobiologists working with economists and psychologists have begun to use our growing understanding of how the nervous system works to develop new models of how the nervous system makes decisions. The result, a growing revolution at the interdisciplinary border of neuroscience, psychology, and economics, is a new field called Neuroeconomics. Emerging neuroeconomic models stand to revolutionize our understanding of human and animal choice behavior by combining fundamental properties of neurobiological representation with decision-theoretic analyses. In this overview, one class of these models, based on the widely observed neural computation known as divisive normalization, is presented in detail. The work demonstrates not only that a discrete class of computation widely observed in the nervous system is fundamentally ubiquitous, but how that computation shapes behaviors ranging from visual perception to financial decision-making. It also offers the hope of reconciling economic analysis of what choices we should make with psychological observations of the choices we actually do make. PMID:25637264

  6. A utility oriented radio resource management algorithm for heterogenous network

    NASA Astrophysics Data System (ADS)

    Wang, Xiaoyan; Dong, Yan; Huang, Zailu

    2007-11-01

    A utility oriented radio resource management algorithm is proposed for broadband nongeostationary satellite network which works in the heterogeneous network environment and provides access services for various customers on the ground. Based on the game theory, the problem for optimizing the network's performance is turned into the problem for maximizing the network's long term utility in the proposed algorithm. With evaluation to the traffic condition and dimensions of Qos for the network at the moment while the access service requirements changing, the influence of this service requirement to the long term utility of the satellite network is audited and then the resource assignment decision can be made according to the rule for maximizing the satellite network's long term utility. The process directed by game theory guaranteed both that the benefit of the network and the requirements of the customers could be considered synthetically. The simulation results demonstrate the effectiveness of the proposed algorithm.

  7. Variability and typical error in the kinematics and kinetics of the maximal instep kick in soccer.

    PubMed

    Lees, Adrian; Rahnama, Nader

    2013-09-01

    The purpose of this paper was to establish the variability and typical error of kinematic and kinetic variables representing the maximal instep kick in soccer for both the kicking and support legs. Ten skilled (good amateur or semi-professional) soccer players performed 20 maximal instep kicks of a stationary ball into a goal mouth. Motion of the kicking and support legs was recorded by an optoelectronic motion analysis system, and a six degrees of freedom model was used to compute kinematic and kinetic variables. Participants repeated the kicks on a second day at least 1 week later. The mean within-subject coefficient of variation across the kinematic and kinetic variables, trials, and days was 16% and did not change substantially as trial number increased or between day of test. Increasing trial number reduced the typical error (as determined by the standard error of the mean) such that for 20 trials 75% of the variables were below an arbitrary 5% threshold. It was concluded that for kicking investigations, 10-15 trials could be used and typical errors of 5% should be expected. PMID:24245053

  8. Attenuated maximal muscle strength and peak power in children with sickle cell disease.

    PubMed

    Dougherty, Kelly A; Schall, Joan I; Rovner, Alisha J; Stallings, Virginia A; Zemel, Babette S

    2011-03-01

    Dominant hand maximal handgrip strength evaluated with a handgrip dynamometer and peak power evaluated with a force plate, adjusted for body size and composition, were compared in African-American children aged 5 to 13 years, with and without type SS sickle cell disease (SCD-SS). Children with SCD-SS (n = 35; age, 9.0 2.0 y) compared with healthy control children (n = 103; age, 8.6 1.8 y) did not differ by age, sex, or pubertal status, yet had significantly lower Z scores for height, weight, body mass index, upper arm muscle area, upper arm fat area, fat mass-for-height and lean mass-for-height. Children with SCD-SS had significantly lower handgrip strength (12.7 3.3 vs. 15.2 5.1 kg, P < 0.008), peak power (882 298 vs. 1167 384 W, P < 0.001), and growth and body composition adjusted Z scores for handgrip strength (0.6 1.3 standard deviations, P < 0.004) and peak power (male children = 1.0 0.8 standard deviations, P < 0.0002; female children = 1.0 1.7 standard deviations, P < 0.006). Maximal muscle strength and peak power are attenuated in children with SCD-SS compared with healthy control children beyond expectation for growth and body composition deficits suggesting that additional factors contribute to attenuation in anaerobic performance. PMID:21228717

  9. The bond ionicity in ANB8-N compounds from maximally localized Wannier functions

    NASA Astrophysics Data System (ADS)

    Qteish, Abdallah

    2015-07-01

    The bond ionicity in seventy two ANB8-N compounds is investigated according to the recently introduced first-principles ionicity scale, based on the centers of the maximally localized Wannier functions, which has several interesting features. The obtained bond ionicities (qi) are found to exhibit the expected trends, according to electronegativity arguments. In particular, the bond ionicity in the alkaline-earth oxides increases by going from MgO to BaO. A strong crystal structure dependence of qi is observed. A critical value of qi (of 0.91) that separates between the tetrahedrally and octahedrally coordinated systems is inferred directly from the calculated values of qi. The volume dependence of qi is investigated for all the considered compounds and found to reduce by volume decrease for most of the studied systems. The adopted ionicity scale is established as a very strong competitor to the most widely accepted Phillips and Pauling ionicity measures.

  10. [The effects of teacher expectancy and self-expectancy on performance].

    PubMed

    Choi, K S

    1987-08-01

    The present study was designed to investigate the effect on performance of the relationship between teacher expectancy and self-expectancy. For the induced expectancy, a random half of 96 high school students enrolled in a four-week summer language course of a Christian association were described to the instructors as having high success potential. The remaining trainees served as controls. Correct scores on the learning task, instructor ratings of behavior and attitude of the instructors were measured on three sessions of the course. Ratings of teacher's behavior were factor-analyzed and four interpretable factors emerged: Support, Caring, Attention, and Tutoring. The induced expectancy and specific levels of self-expectancy had significant effects on the subjects' performance and ratings of the instructor. It was concluded that self-expectancy mediates the effects of teacher expectancy on learning performance. Implications of these results for the Pygmalion effect were discussed. PMID:3450908

  11. Components of attention modulated by temporal expectation.

    PubMed

    Srensen, Thomas Alrik; Vangkilde, Signe; Bundesen, Claus

    2015-01-01

    By varying the probabilities that a stimulus would appear at particular times after the presentation of a cue and modeling the data by the theory of visual attention (Bundesen, 1990), Vangkilde, Coull, and Bundesen (2012) provided evidence that the speed of encoding a singly presented stimulus letter into visual short-term memory (VSTM) is modulated by the observer's temporal expectations. We extended the investigation from single-stimulus recognition to whole report (Experiment 1) and partial report (Experiment 2). Cue-stimulus foreperiods were distributed geometrically using time steps of 500 ms. In high expectancy conditions, the probability that the stimulus would appear on the next time step, given that it had not yet appeared, was high, whereas in low expectancy conditions, the probability was low. The speed of encoding the stimuli into VSTM was higher in the high expectancy conditions. In line with the Easterbrook (1959) hypothesis, under high temporal expectancy, the processing was also more focused (selective). First, the storage capacity of VSTM was lower, so that fewer stimuli were encoded into VSTM. Second, the distribution of attentional weights across stimuli was less even: The efficiency of selecting targets rather than distractors for encoding into VSTM was higher, as was the spread of the attentional weights of the target letters. PMID:25068851

  12. Dynamically disordered quantum walk as a maximal entanglement generator.

    PubMed

    Vieira, Rafael; Amorim, Edgard P M; Rigolin, Gustavo

    2013-11-01

    We show that the entanglement between the internal (spin) and external (position) degrees of freedom of a qubit in a random (dynamically disordered) one-dimensional discrete time quantum random walk (QRW) achieves its maximal possible value asymptotically in the number of steps, outperforming the entanglement attained by using ordered QRW. The disorder is modeled by introducing an extra random aspect to QRW, a classical coin that randomly dictates which quantum coin drives the system's time evolution. We also show that maximal entanglement is achieved independently of the initial state of the walker, study the number of steps the system must move to be within a small fixed neighborhood of its asymptotic limit, and propose two experiments where these ideas can be tested. PMID:24237496

  13. Magellan Project: Evolving enhanced operations efficiency to maximize science value

    NASA Technical Reports Server (NTRS)

    Cheuvront, Allan R.; Neuman, James C.; Mckinney, J. Franklin

    1994-01-01

    Magellan has been one of NASA's most successful spacecraft, returning more science data than all planetary spacecraft combined. The Magellan Spacecraft Team (SCT) has maximized the science return with innovative operational techniques to overcome anomalies and to perform activities for which the spacecraft was not designed. Commanding the spacecraft was originally time consuming because the standard development process was envisioned as manual tasks. The Program understood that reducing mission operations costs were essential for an extended mission. Management created an environment which encouraged automation of routine tasks, allowing staff reduction while maximizing the science data returned. Data analysis and trending, command preparation, and command reviews are some of the tasks that were automated. The SCT has accommodated personnel reductions by improving operations efficiency while returning the maximum science data possible.

  14. Quantitative Analysis of Single Particle Trajectories: Mean Maximal Excursion Method

    PubMed Central

    Tejedor, Vincent; Bénichou, Olivier; Voituriez, Raphael; Jungmann, Ralf; Simmel, Friedrich; Selhuber-Unkel, Christine; Oddershede, Lene B.; Metzler, Ralf

    2010-01-01

    An increasing number of experimental studies employ single particle tracking to probe the physical environment in complex systems. We here propose and discuss what we believe are new methods to analyze the time series of the particle traces, in particular, for subdiffusion phenomena. We discuss the statistical properties of mean maximal excursions (MMEs), i.e., the maximal distance covered by a test particle up to time t. Compared to traditional methods focusing on the mean-squared displacement we show that the MME analysis performs better in the determination of the anomalous diffusion exponent. We also demonstrate that combination of regular moments with moments of the MME method provides additional criteria to determine the exact physical nature of the underlying stochastic subdiffusion processes. We put the methods to test using experimental data as well as simulated time series from different models for normal and anomalous dynamics such as diffusion on fractals, continuous time random walks, and fractional Brownian motion. PMID:20371337

  15. Maximal aerobic power measurement in runners and swimmers.

    PubMed Central

    Corry, I.; Powers, N.

    1982-01-01

    Five cross-country runners and five competitive swimmers performed a pulling exercise with elastic shock cords and a treadmill run to exhaustion. The mean VO2 max related to lean body mass of the runners was significantly higher than the swimmers on the treadmill (p less than 0.05) while, on the pulling test, the mean VO2 max of the swimmers was significantly higher than the runners (p less 0.01). The maximum heart rates achieved pulling were 95% of the running maximum by runners and 96% by swimmers with no significant difference between them. Their mean oxygen pulse was almost the same for maximal running but the swimmers had a significantly higher oxygen pulse than the runners for maximal pulling (p less than 0.01). The swimmers could reach about 79% of their running VO2 max by pulling while the runners used 53% of their running VO2 max. Images Fig. 1 Fig. 3 PMID:7139226

  16. Maximizing production rates of the Linde Hampson machine

    NASA Astrophysics Data System (ADS)

    Maytal, B.-Z.

    2006-01-01

    In contrast to the ideal case of unlimited size recuperator, any real Linde-Hampson machine of finite size recuperator can be optimized to reach the extreme rates of performance. The group of cryocoolers sharing the same size recuperator is optimized in a closed form by determining the corresponding flow rate which maximizes its rate of cold production. For a similar group of liquefiers an optimal flow rate is derived to maximize the rate of production of liquid cryogen. The group of cryocoolers sharing a constant and given flow rate is optimized by shortening the recuperator for reaching a maximum compactness measured by the cooling power per unit size of the recuperator. The optimum conditions are developed for nitrogen and argon. The relevance of this analysis is discussed in the context of practice of fast cooldown Joule-Thomson cryocooling.

  17. Maximal radius of the aftershock zone in earthquake networks

    NASA Astrophysics Data System (ADS)

    Mezentsev, A. Yu.; Hayakawa, M.

    2009-09-01

    In this paper, several seismoactive regions were investigated (Japan, Southern California and two tectonically distinct Japanese subregions) and structural seismic constants were estimated for each region. Using the method for seismic clustering detection proposed by Baiesi and Paczuski [M. Baiesi, M. Paczuski, Phys. Rev. E 69 (2004) 066106; M. Baiesi, M. Paczuski, Nonlin. Proc. Geophys. (2005) 1607-7946], we obtained the equation of the aftershock zone (AZ). It was shown that the consideration of a finite velocity of seismic signal leads to the natural appearance of maximal possible radius of the AZ. We obtained the equation of maximal radius of the AZ as a function of the magnitude of the main event and estimated its values for each region.

  18. Mosaics of retinal cells that transmit maximal information

    NASA Astrophysics Data System (ADS)

    Sharpee, Tatyana

    2008-03-01

    In the nervous system, visual signals are encoded by retinal ganglion cells into sequences of discrete electrical pulses termed spikes. Response regions of different ganglion cells tile the visual field and are arranged on approximately hexagonal lattice. Here we consider the optimal arrangement of response regions that would collectively allow for maximal information transmitted about the location of a point light source. We find that maximal information can be transmitted when at most three neighboring regions overlap and the average radius of response field is 0.67 of the distance between response field centers. This finding was obtained with no adjustable parameters and agrees with experimental measurements of retinal mosaics [1, 2]. [1] D.M. Dacey and S. Brace, Visual Neuroscience 9:279-90 (1992). [2] S.H. Devries and D.A. Baylor, J Neurophysiol. 78:2048-60 (1997).

  19. Maximally informative ensembles for SIC-POVMs in dimension 3

    NASA Astrophysics Data System (ADS)

    Szymusiak, Anna

    2014-11-01

    In order to find out for which initial states of the system the uncertainty of the measurement outcomes will be minimal, one can look for the minimizers of the Shannon entropy of the measurement. In case of group-covariant measurements this question becomes closely related to the problem of how informative the measurement is in the sense of its informational power. Namely, the orbit under group action of the entropy minimizer corresponds to a maximally informative ensemble of equiprobable elements. We give a characterization of such ensembles for three-dimensional group-covariant (Weyl-Heisenberg) symmetric informationally complete positive operator valued measures (SIC-POVMs) in both geometric and algebraic terms. It turns out that a maximally informative ensemble arises from the input state orthogonal to a subspace spanned by three linearly dependent vectors defining a SIC-POVM (geometrically) or from an eigenstate of a certain Weyl matrix (algebraically).

  20. Self-dual metrics with maximally superintegrable geodesic flows

    NASA Astrophysics Data System (ADS)

    Filyukov, Sergei; Galajinsky, Anton

    2015-05-01

    A class of self-dual and geodesically complete spacetimes with maximally superintegrable geodesic flows is constructed by applying the Eisenhart lift to mechanics in pseudo-Euclidean spacetime of signature (1,1). It is characterized by the presence of a second-rank Killing tensor. Spacetimes of the ultrahyperbolic signature (2 ,q ) with q >2 , which admit a second-rank Killing tensor and possess superintegrable geodesic flows, are built.

  1. An entropy maximization problem related to optical communication

    NASA Technical Reports Server (NTRS)

    Mceliece, R. J.; Rodemich, E. R.; Swanson, L.

    1986-01-01

    In relation to a problem in optical communication, the paper considers the general problem of maximizing the entropy of a stationary radom process that is subject to an average transition cost constraint. By using a recent result of Justesen and Hoholdt, an exact solution to the problem is presented and a class of finite state encoders that give a good approximation to the exact solution is suggested.

  2. Limited Maximal Exercise Capacity in Patients With Chronic Heart Failure

    PubMed Central

    Esposito, Fabio; Mathieu-Costello, Odile; Shabetai, Ralph; Wagner, Peter D.; Richardson, Russell S.

    2016-01-01

    Objectives This study aimed to assess the factors limiting maximal exercise capacity in patients with chronic heart failure (CHF). Background Maximal exercise capacity, an important index of health in CHF, might be limited by central and/or peripheral factors; however, their contributions remain poorly understood. Methods We studied oxygen (O2) transport and metabolism at maximal cycle (centrally taxing) and knee-extensor (KE) (peripherally taxing) exercise in 12 patients with CHF and 8 healthy control subjects in normoxia and hyperoxia (100% O2). Results Peak oxygen uptake (VO2) while cycling was 33% lower in CHF patients than in control subjects. By experimental design, peak cardiac output was reduced during KE exercise when compared with cycling (approximately 35%); although muscle mass specific peak leg VO2 was increased equally in both groups (approximately 70%), VO2 in the CHF patients was still 28% lower. Hyperoxia increased O2 carriage in all cases but only facilitated a 7% increase in peak leg VO2 in the CHF patients during cycling, the most likely scenario to benefit from increased O2 delivery. Several relationships, peak leg VO2 (KE + cycle) to capillary-fiber-ratio and capillaries around a fiber to mitochondrial volume, were similar in both groups (r = 0.6-0.7). Conclusions Multiple independent observations, including a significant skeletal muscle metabolic reserve, suggest skeletal muscle per se contributes minimally to limiting maximal cycle exercise in CHF or healthy control subjects. However, the consistent attenuation of the convective and diffusive components of O2 transport (25% to 30%) in patients with CHF during both cycle and even KE exercise compared with control subjects reveals an underlying peripheral O2 transport limitation from blood to skeletal muscle in this pathology. PMID:20430267

  3. Planning for partnerships: Maximizing surge capacity resources through service learning.

    PubMed

    Adams, Lavonne M; Reams, Paula K; Canclini, Sharon B

    2015-01-01

    Infectious disease outbreaks and natural or human-caused disasters can strain the community's surge capacity through sudden demand on healthcare activities. Collaborative partnerships between communities and schools of nursing have the potential to maximize resource availability to meet community needs following a disaster. This article explores how communities can work with schools of nursing to enhance surge capacity through systems thinking, integrated planning, and cooperative efforts. PMID:26750818

  4. Content Specificity of Expectancy Beliefs and Task Values in Elementary Physical Education

    PubMed Central

    Chen, Ang; Martin, Robert; Ennis, Catherine D.; Sun, Haichun

    2015-01-01

    The curriculum may superimpose a content-specific context that mediates motivation (Bong, 2001). This study examined content specificity of the expectancy-value motivation in elementary school physical education. Students’ expectancy beliefs and perceived task values from a cardiorespiratory fitness unit, a muscular fitness unit, and a traditional skill/game unit were analyzed using constant comparison coding procedures, multivariate analysis of variance, χ2, and correlation analyses. There was no difference in the intrinsic interest value among the three content conditions. Expectancy belief, attainment, and utility values were significantly higher for the cardiorespiratory fitness curriculum. Correlations differentiated among the expectancy-value components of the content conditions, providing further evidence of content specificity in the expectancy-value motivation process. The findings suggest that expectancy beliefs and task values should be incorporated in the theoretical platform for curriculum development based on the learning outcomes that can be specified with enhanced motivation effect. PMID:18664044

  5. [Live longer, suffer more? Trends in life expectancy and health].

    PubMed

    Doblhammer, G; Kreft, D

    2011-08-01

    During the 20thcentury, life expectancy has been continuously increasing with the majority of the additional years resulting from decreasing mortality among the old and oldest old in the last few decades. Two phases of convergence and divergence in European mortality have been identified, with a possible new phase of divergence taking place among the oldest old. Over this period, women have always been living longer than men. Explanations for this phenomenon include not only biological factors and differences in lifestyle and health care utilization, but also differences in reporting patterns. Trends in health do not follow a clear direction. Reasons are the different dimensions of health as well as inadequate data. In general, the prevalence of morbidity has been increasing, while functional limitations and ADL disabilities have been decreasing. Due to a lack of data, no information exists for trends among the oldest old at age 80 and above. In absolute terms, the number of healthy years has been increasing with increasing life expectancy. In relative terms, they have been stable, probably slightly increasing in some countries. These trends suggest that increasing life expectancy does not result in an increase in morbidity. PMID:21800237

  6. Operation of MRO's High Resolution Imaging Science Experiment (HiRISE): Maximizing Science Participation

    NASA Technical Reports Server (NTRS)

    Eliason, E.; Hansen, C. J.; McEwen, A.; Delamere, W. A.; Bridges, N.; Grant, J.; Gulich, V.; Herkenhoff, K.; Keszthelyi, L.; Kirk, R.

    2003-01-01

    Science return from the Mars Reconnaissance Orbiter (MRO) High Resolution Imaging Science Experiment (HiRISE) will be optimized by maximizing science participation in the experiment. MRO is expected to arrive at Mars in March 2006, and the primary science phase begins near the end of 2006 after aerobraking (6 months) and a transition phase. The primary science phase lasts for almost 2 Earth years, followed by a 2-year relay phase in which science observations by MRO are expected to continue. We expect to acquire approx. 10,000 images with HiRISE over the course of MRO's two earth-year mission. HiRISE can acquire images with a ground sampling dimension of as little as 30 cm (from a typical altitude of 300 km), in up to 3 colors, and many targets will be re-imaged for stereo. With such high spatial resolution, the percent coverage of Mars will be very limited in spite of the relatively high data rate of MRO (approx. 10x greater than MGS or Odyssey). We expect to cover approx. 1% of Mars at approx. 1m/pixel or better, approx. 0.1% at full resolution, and approx. 0.05% in color or in stereo. Therefore, the placement of each HiRISE image must be carefully considered in order to maximize the scientific return from MRO. We believe that every observation should be the result of a mini research project based on pre-existing datasets. During operations, we will need a large database of carefully researched 'suggested' observations to select from. The HiRISE team is dedicated to involving the broad Mars community in creating this database, to the fullest degree that is both practical and legal. The philosophy of the team and the design of the ground data system are geared to enabling community involvement. A key aspect of this is that image data will be made available to the planetary community for science analysis as quickly as possible to encourage feedback and new ideas for targets.

  7. Polarity related influence maximization in signed social networks.

    PubMed

    Li, Dong; Xu, Zhi-Ming; Chakraborty, Nilanjan; Gupta, Anika; Sycara, Katia; Li, Sheng

    2014-01-01

    Influence maximization in social networks has been widely studied motivated by applications like spread of ideas or innovations in a network and viral marketing of products. Current studies focus almost exclusively on unsigned social networks containing only positive relationships (e.g. friend or trust) between users. Influence maximization in signed social networks containing both positive relationships and negative relationships (e.g. foe or distrust) between users is still a challenging problem that has not been studied. Thus, in this paper, we propose the polarity-related influence maximization (PRIM) problem which aims to find the seed node set with maximum positive influence or maximum negative influence in signed social networks. To address the PRIM problem, we first extend the standard Independent Cascade (IC) model to the signed social networks and propose a Polarity-related Independent Cascade (named IC-P) diffusion model. We prove that the influence function of the PRIM problem under the IC-P model is monotonic and submodular Thus, a greedy algorithm can be used to achieve an approximation ratio of 1-1/e for solving the PRIM problem in signed social networks. Experimental results on two signed social network datasets, Epinions and Slashdot, validate that our approximation algorithm for solving the PRIM problem outperforms state-of-the-art methods. PMID:25061986

  8. Reference values of maximal oxygen uptake for polish rowers.

    PubMed

    Klusiewicz, Andrzej; Starczewski, Micha?; ?adyga, Maria; D?ugo??cka, Barbara; Braksator, Wojciech; Mamcarz, Artur; Sitkowski, Dariusz

    2014-12-01

    The aim of this study was to characterize changes in maximal oxygen uptake over several years and to elaborate current reference values of this index based on determinations carried out in large and representative groups of top Polish rowers. For this study 81 female and 159 male rowers from the sub-junior to senior categories were recruited from the Polish National Team and its direct backup. All the subjects performed an incremental exercise test on a rowing ergometer. During the test maximal oxygen uptake was measured with the BxB method. The calculated reference values for elite Polish junior and U23 rowers allowed to evaluate the athletes' fitness level against the respective reference group and may aid the coach in controlling the training process. Mean values of VO2max achieved by members of the top Polish rowing crews who over the last five years competed in the Olympic Games or World Championships were also presented. The results of the research on the "trainability" of the maximal oxygen uptake may lead to a conclusion that the growth rate of the index is larger in case of high-level athletes and that the index (in absolute values) increases significantly between the age of 19-22 years (U23 category). PMID:25713672

  9. Random effects structure for confirmatory hypothesis testing: Keep it maximal

    PubMed Central

    Barr, Dale J.; Levy, Roger; Scheepers, Christoph; Tily, Harry J.

    2013-01-01

    Linear mixed-effects models (LMEMs) have become increasingly prominent in psycholinguistics and related areas. However, many researchers do not seem to appreciate how random effects structures affect the generalizability of an analysis. Here, we argue that researchers using LMEMs for confirmatory hypothesis testing should minimally adhere to the standards that have been in place for many decades. Through theoretical arguments and Monte Carlo simulation, we show that LMEMs generalize best when they include the maximal random effects structure justified by the design. The generalization performance of LMEMs including data-driven random effects structures strongly depends upon modeling criteria and sample size, yielding reasonable results on moderately-sized samples when conservative criteria are used, but with little or no power advantage over maximal models. Finally, random-intercepts-only LMEMs used on within-subjects and/or within-items data from populations where subjects and/or items vary in their sensitivity to experimental manipulations always generalize worse than separate F1 and F2 tests, and in many cases, even worse than F1 alone. Maximal LMEMs should be the gold standard for confirmatory hypothesis testing in psycholinguistics and beyond. PMID:24403724

  10. Polarity Related Influence Maximization in Signed Social Networks

    PubMed Central

    Li, Dong; Xu, Zhi-Ming; Chakraborty, Nilanjan; Gupta, Anika; Sycara, Katia; Li, Sheng

    2014-01-01

    Influence maximization in social networks has been widely studied motivated by applications like spread of ideas or innovations in a network and viral marketing of products. Current studies focus almost exclusively on unsigned social networks containing only positive relationships (e.g. friend or trust) between users. Influence maximization in signed social networks containing both positive relationships and negative relationships (e.g. foe or distrust) between users is still a challenging problem that has not been studied. Thus, in this paper, we propose the polarity-related influence maximization (PRIM) problem which aims to find the seed node set with maximum positive influence or maximum negative influence in signed social networks. To address the PRIM problem, we first extend the standard Independent Cascade (IC) model to the signed social networks and propose a Polarity-related Independent Cascade (named IC-P) diffusion model. We prove that the influence function of the PRIM problem under the IC-P model is monotonic and submodular Thus, a greedy algorithm can be used to achieve an approximation ratio of 1-1/e for solving the PRIM problem in signed social networks. Experimental results on two signed social network datasets, Epinions and Slashdot, validate that our approximation algorithm for solving the PRIM problem outperforms state-of-the-art methods. PMID:25061986

  11. Maximal entanglement of two delocalized spin-1/2 particles

    NASA Astrophysics Data System (ADS)

    Johansson, Markus

    2016-02-01

    We describe the entanglement of two indistinguishable delocalized spin-1/2 particles in the simplest spatial configuration of three spatial modes with the constraint that at most one particle occupy each mode. It is shown that this is the only number of modes for which maximally entangled states exist in such a system. The set of entangled states, including the set of maximally entangled states, is described and different types of entanglement in terms of Bell-nonlocal correlations for different partitions of the system are identified. In particular we focus on the entangled states that are Bell local for a tripartition of the system and cannot be described as a superposition of bipartite entangled pairs of localized particles. Two entanglement invariants are constructed and it is shown that all entanglement monotones are functions of these. Furthermore, the system has a generic nontrivial local unitary symmetry with a corresponding 2 π /3 fractional topological phase. In addition to this a necessary and sufficient condition for the existence of maximally entangled states in systems of arbitrary numbers of delocalized particles with arbitrary spin, where at most one particle can occupy each mode, is derived.

  12. A measurement of the maximal forces in plasmonic tweezers

    NASA Astrophysics Data System (ADS)

    Kim, Jung-Dae; Choi, Jun-Hee; Lee, Yong-Gu

    2015-10-01

    Plasmonic tweezers that are designed to trap nanoscale objects create many new possibilities for single-molecule targeted studies. Numerous novel designs of plasmonic nanostructures are proposed in order to attain stronger forces and weaker laser intensity. Most experiments have consisted only of immobilization observations—that is, particles stick when the laser is turned on and fall away when the laser is turned off. Studies of the exertable forces were only theoretical. A few studies have experimentally measured trap stiffness. However, as far as we know, no studies have addressed maximal forces. In this paper, we present a new experimental design in which the motion of the trapped particle can be monitored in either parallel or orthogonal directions to the plasmonic structure’s symmetric axis. We measured maximal trapping force through such monitoring. Although stiffness would be useful for force-calibration or immobilization purposes, for which most plasmonic tweezers are used, we believe that the maximal endurable force is significant and thus, this paper presents this aspect.

  13. An efficient community detection algorithm using greedy surprise maximization

    NASA Astrophysics Data System (ADS)

    Jiang, Yawen; Jia, Caiyan; Yu, Jian

    2014-04-01

    Community detection is an important and crucial problem in complex network analysis. Although classical modularity function optimization approaches are widely used for identifying communities, the modularity function (Q) suffers from its resolution limit. Recently, the surprise function (S) was experimentally proved to be better than the Q function. However, up until now, there has been no algorithm available to perform searches to directly determine the maximal surprise values. In this paper, considering the superiority of the S function over the Q function, we propose an efficient community detection algorithm called AGSO (algorithm based on greedy surprise optimization) and its improved version FAGSO (fast-AGSO), which are based on greedy surprise optimization and do not suffer from the resolution limit. In addition, (F)AGSO does not need the number of communities K to be specified in advance. Tests on experimental networks show that (F)AGSO is able to detect optimal partitions in both simple and even more complex networks. Moreover, algorithms based on surprise maximization perform better than those algorithms based on modularity maximization, including Blondel-Guillaume-Lambiotte-Lefebvre (BGLL), Clauset-Newman-Moore (CNM) and the other state-of-the-art algorithms such as Infomap, order statistics local optimization method (OSLOM) and label propagation algorithm (LPA).

  14. Camera scheduling and energy allocation for lifetime maximization in user-centric visual sensor networks.

    PubMed

    Yu, Chao; Sharma, Gaurav

    2010-08-01

    We explore camera scheduling and energy allocation strategies for lifetime optimization in image sensor networks. For the application scenarios that we consider, visual coverage over a monitored region is obtained by deploying wireless, battery-powered image sensors. Each sensor camera provides coverage over a part of the monitored region and a central processor coordinates the sensors in order to gather required visual data. For the purpose of maximizing the network operational lifetime, we consider two problems in this setting: a) camera scheduling, i.e., the selection, among available possibilities, of a set of cameras providing the desired coverage at each time instance, and b) energy allocation, i.e., the distribution of total available energy between the camera sensor nodes. We model the network lifetime as a stochastic random variable that depends upon the coverage geometry for the sensors and the distribution of data requests over the monitored region, two key characteristics that distinguish our problem from other wireless sensor network applications. By suitably abstracting this model of network lifetime and utilizing asymptotic analysis, we propose lifetime-maximizing camera scheduling and energy allocation strategies. The effectiveness of the proposed camera scheduling and energy allocation strategies is validated by simulations. PMID:20350857

  15. Spatiotemporal laser speckle contrast analysis for blood flow imaging with maximized speckle contrast.

    PubMed

    Qiu, Jianjun; Li, Pengcheng; Luo, Weihua; Wang, Jia; Zhang, Hongyan; Luo, Qingming

    2010-01-01

    Laser speckle contrast imaging is a technique used for imaging blood flow without scanning. Though several studies have attempted to combine spatial and temporal statistics of laser speckle images for reducing image noise as well as preserving acceptable spatiotemporal resolution, the statistical accuracy of these spatiotemporal methods has not been thoroughly compared. Through numerical simulation and animal experiments, this study investigates the changes in the mean speckle contrast values and the relative noise of the speckle contrast images computed by these methods with various numbers of frames and spatial windows. The simulation results show that the maximum relative error of the mean speckle contrast computed by the spatiotemporal laser speckle contrast analysis (STLASCA) method, in which the speckle contrast images are computed by analyzing the 3-D spatiotemporal speckle image cube, is approximately 5%, while it is higher than 13% for other methods. Changes in the mean speckle contrast values and the relative noise computed by these methods for animal experiment data are consistent with the simulation results. Our results demonstrate that STLASCA achieves more accurate speckle contrast, and suggest that STLASCA most effectively utilizes the number of pixels, thus achieving maximized speckle contrast, and thereby maximizing the variation of the laser speckle contrast image. PMID:20210450

  16. A mixture of "cheats" and "co-operators" can enable maximal group benefit.

    PubMed

    MaClean, R Craig; Fuentes-Hernandez, Ayari; Greig, Duncan; Hurst, Laurence D; Gudelj, Ivana

    2010-01-01

    Is a group best off if everyone co-operates? Theory often considers this to be so (e.g. the "conspiracy of doves"), this understanding underpinning social and economic policy. We observe, however, that after competition between "cheat" and "co-operator" strains of yeast, population fitness is maximized under co-existence. To address whether this might just be a peculiarity of our experimental system or a result with broader applicability, we assemble, benchmark, dissect, and test a systems model. This reveals the conditions necessary to recover the unexpected result. These are 3-fold: (a) that resources are used inefficiently when they are abundant, (b) that the amount of co-operation needed cannot be accurately assessed, and (c) the population is structured, such that co-operators receive more of the resource than the cheats. Relaxing any of the assumptions can lead to population fitness being maximized when cheats are absent, which we experimentally demonstrate. These three conditions will often be relevant, and hence in order to understand the trajectory of social interactions, understanding the dynamics of the efficiency of resource utilization and accuracy of information will be necessary. PMID:20856906

  17. Maximal heart rate does not limit cardiovascular capacity in healthy humans: insight from right atrial pacing during maximal exercise

    PubMed Central

    Munch, G D W; Svendsen, J H; Damsgaard, R; Secher, N H; González-Alonso, J; Mortensen, S P

    2014-01-01

    In humans, maximal aerobic power () is associated with a plateau in cardiac output (), but the mechanisms regulating the interplay between maximal heart rate (HRmax) and stroke volume (SV) are unclear. To evaluate the effect of tachycardia and elevations in HRmax on cardiovascular function and capacity during maximal exercise in healthy humans, 12 young male cyclists performed incremental cycling and one-legged knee-extensor exercise (KEE) to exhaustion with and without right atrial pacing to increase HR. During control cycling, and leg blood flow increased up to 85% of maximal workload (WLmax) and remained unchanged until exhaustion. SV initially increased, plateaued and then decreased before exhaustion (P < 0.05) despite an increase in right atrial pressure (RAP) and a tendency (P = 0.056) for a reduction in left ventricular transmural filling pressure (LVFP). Atrial pacing increased HRmax from 184 ± 2 to 206 ± 3 beats min−1 (P < 0.05), but remained similar to the control condition at all intensities because of a lower SV and LVFP (P < 0.05). No differences in arterial pressure, peripheral haemodynamics, catecholamines or were observed, but pacing increased the rate pressure product and RAP (P < 0.05). Atrial pacing had a similar effect on haemodynamics during KEE, except that pacing decreased RAP. In conclusion, the human heart can be paced to a higher HR than observed during maximal exercise, suggesting that HRmax and myocardial work capacity do not limit in healthy individuals. A limited left ventricular filling and possibly altered contractility reduce SV during atrial pacing, whereas a plateau in LVFP appears to restrict close to . Key points During high intensity whole-body exercise, systemic and contracting skeletal muscle O2 delivery and uptake (>) are compromised, but the underlying mechanisms remain unclear. We evaluated the effect of a ∼20 beats min−1 increase in heart rate (HR) by right atrial pacing during incremental cycling and knee-extensor exercise on cardiac output () and stroke volume (SV). An increase in HR during both exercise modalities did not alter due to a proportional decrease in SV. The lower SV during atrial pacing in the cycling trial was associated with a diminished cardiac filling pressure, but similar arterial pressure. The results demonstrate that the human heart can achieve a higher HR than observed during maximal exercise, suggesting that HRmax and myocardial work capacity do not limit cardiac performance in trained human subjects. Instead, restrictions in ventricular filling appear to compromise cardiac preload, SV and at exercise intensities close to . PMID:24190933

  18. Major League Baseball Players Life Expectancies*

    PubMed Central

    Saint Onge, Jarron M.; Rogers, Richard G.; Krueger, Patrick M.

    2009-01-01

    Objective We examine the importance of anthropometric and performance measures, and age, period, and cohort effects in explaining life expectancies among major league baseball (MLB) players over the past century. Methods We use discrete time hazard models to calculate life tables with covariates with data from Total Baseball, a rich source of information on all players who played in the major league. Results Compared to 20-year-old U.S. males, MLB players can expect almost five additional years of life. Height, weight, handedness, and player ratings are unassociated with the risk of death in this population of highly active and successful adults. Career length is inversely associated with the risk of death, likely because those who play longer gain additional incomes, physical fitness, and training. Conclusions Our results indicate improvements in life expectancies with time for all age groups and indicate possible improvements in longevity in the general U.S. population. PMID:19756205

  19. Information structure expectations in sentence comprehension

    PubMed Central

    Carlson, Katy; Dickey, Michael Walsh; Frazier, Lyn; Clifton, Charles

    2009-01-01

    In English, new information typically appears late in the sentence, as does primary accent. Because of this tendency, perceivers might expect the final constituent or constituents of a sentence to contain informational focus. This expectation should in turn affect how they comprehend focus-sensitive constructions such as ellipsis sentences. Results from four experiments on sluicing sentences (e.g., The mobster implicated the thug, but we cant find out who else) suggest that perceivers do prefer to place focus late in the sentence, though that preference can be mitigated by prosodic information (pitch accents, Experiment 2) or syntactic information (clefted sentences, Experiment 3) indicating that focus is located elsewhere. Furthermore, it is not necessarily the direct object, but the informationally-focused constituent that is the preferred antecedent (Experiment 4). Expectations regarding the information structure of a sentence, which are only partly cancelable by means of overt focus markers, may explain persistent biases in ellipsis resolution. PMID:18609404

  20. Maternal expectations: do they match experience?

    PubMed

    Young, Eleanor

    2008-10-01

    This qualitative research project aimed to explore maternal expectations toward motherhood and compare these to actual experience, in order to identify where expectations were not being met and inform the improvement of services. The project involved two focus groups involving a midwife, health visitors, a community psychiatric nurse and a nursery nurse, and individual semistructured interviews with 11 first-time mothers. Questions were asked about antenatal and postnatal services and about maternal expectations. The findings indicated that there were some areas for which parents did not feel well prepared and where care could be more focused. The needs that were identified included earlier antenatal classes with greater involvement from fathers and health visitors, opportunities to debrief about labour, more information on practical, emotional and relationship changes, and more opportunities for mothers to support each other. PMID:18853885

  1. Maximizing Total QoS-Provisioning of Image Streams with Limited Energy Budget

    NASA Astrophysics Data System (ADS)

    Lee, Wan Yeon; Kim, Kyong Hoon; Ko, Young Woong

    To fully utilize the limited battery energy of mobile electronic devices, we propose an adaptive adjustment method of processing quality for multiple image stream tasks running with widely varying execution times. This adjustment method completes the worst-case executions of the tasks with a given budget of energy, and maximizes the total reward value of processing quality obtained during their executions by exploiting the probability distribution of task execution times. The proposed method derives the maximum reward value for the tasks being executable with arbitrary processing quality, and near maximum value for the tasks being executable with a finite number of processing qualities. Our evaluation on a prototype system shows that the proposed method achieves larger reward values, by up to 57%, than the previous method.

  2. Maximizing the Value of Photovoltaic Installations on Schools in California: Choosing the Best Electricity Rates

    SciTech Connect

    Ong, S.; Denholm, P.

    2011-07-01

    Schools in California often have a choice between multiple electricity rate options. For schools with photovoltaic (PV) installations, choosing the right rate is essential to maximize the value of PV generation. The rate option that minimizes a school?s electricity expenses often does not remain the most economical choice after the school installs a PV system. The complex interaction between PV generation, building load, and rate structure makes determining the best rate a challenging task. This report evaluates 22 rate structures across three of California?s largest electric utilities--Pacific Gas and Electric Co. (PG&E), Southern California Edison (SCE), and San Diego Gas and Electric (SDG&E)--in order to identify common rate structure attributes that are favorable to PV installations.

  3. Great expectations. Eating expectancies as mediators of reinforcement sensitivity and eating.

    PubMed

    Hennegan, Julie M; Loxton, Natalie J; Mattar, Ameerah

    2013-12-01

    Eating expectancies are proposed as cognitive pathways linking reinforcement (reward and punishment) sensitivities and the tendency to over-eat in response to appetitive and emotional cues. In Study One (N=243 university women) explicit eating expectancies were tested as potential mediators of reinforcement sensitivities and eating styles. Broadly, expectancies that eating alleviates negative affect/boredom mediated both reward and punishment sensitivity and emotional eating. The expectancy that eating is pleasurable and rewarding mediated reward sensitivity and external eating. In Study Two (N=109), using an implicit eating expectancy task, reward sensitivity and external eating was mediated via positive expectancy statements, notably, that eating is pleasurable and rewarding. Reward sensitivity and emotional eating was mediated specifically by expectancies that eating manages boredom. Punishment sensitivity was not associated with any implicit expectancies. Findings support the role of expectancies as cognitive mediators in the relationship between reinforcement sensitivities and emotionally-driven versus externally-driven eating styles. However, the largely appetitive implicit expectancies task only supported an association with reward sensitivity. PMID:23932947

  4. Orbiter electrical equipment utilization baseline

    NASA Technical Reports Server (NTRS)

    1980-01-01

    The baseline for utilization of Orbiter electrical equipment in both electrical and Environmental Control and Life Support System (ECLSS) thermal analyses is established. It is a composite catalog of Space Shuttle equipment, as defined in the Shuttle Operational Data Book. The major functions and expected usage of each component type are described. Functional descriptions are designed to provide a fundamental understanding of the Orbiter electrical equipment, to insure correlation of equipment usage within nominal analyses, and to aid analysts in the formulation of off-nominal, contingency analyses.

  5. Solar energy research and utilization

    NASA Technical Reports Server (NTRS)

    Cherry, W. R.

    1974-01-01

    The role of solar energy is visualized in the heating and cooling of buildings, in the production of renewable gaseous, liquid and solid fuels, and in the production of electric power over the next 45 years. Potential impacts of solar energy on various energy markets, and estimated costs of such solar energy systems are discussed. Some typical solar energy utilization processes are described in detail. It is expected that at least 20% of the U.S. total energy requirements by 2020 will be delivered from solar energy.

  6. Utilization of the terrestrial cyanobacteria

    NASA Astrophysics Data System (ADS)

    Katoh, Hiroshi; Tomita-Yokotani, Kaori; Furukawa, Jun; Kimura, Shunta; Yokoshima, Mika; Yamaguchi, Yuji; Takenaka, Hiroyuki

    The terrestrial, N _{2}-fixing cyanobacterium, Nostoc commune has expected to utilize for agriculture, food and terraforming cause of its extracellular polysaccharide, desiccation tolerance and nitrogen fixation. Previously, the first author indicated that desiccation related genes were analyzed and the suggested that the genes were related to nitrogen fixation and metabolisms. In this report, we suggest possibility of agriculture, using the cyanobacterium. Further, we also found radioactive compounds accumulated N. commune (cyanobacterium) in Fukushima, Japan after nuclear accident. Thus, it is investigated to decontaminate radioactive compounds from the surface soil by the cyanobacterium and showed to accumulate radioactive compounds using the cyanobacterium. We will discuss utilization of terrestrial cyanobacteria under closed environment. Keyword: Desiccation, terrestrial cyanobacteria, bioremediation, agriculture

  7. Athletic Differences in the Characteristics of the Photoplethysmographic Pulse Shape: Effect of Maximal Oxygen Uptake and Maximal Muscular Voluntary Contraction

    PubMed Central

    Wang, Anran; Yang, Lin; Liu, Chengyu; Cui, Jingxuan; Li, Yao; Yang, Xingxing; Zhang, Song

    2015-01-01

    This study aimed to investigate the athletic differences in the characteristics of the photoplethysmographic (PPG) pulse shape. 304 athletes were enrolled and divided into three subgroups according to a typical sport classification in terms of the maximal oxygen uptake (MaxO2_low, MaxO2_middle and MaxO2_high groups) or the maximal muscular voluntary contraction (MMVC_low, MMVC_middle, and MMVC_high groups). Finger PPG pulses were digitally recorded and then normalized to derive the pulse area, pulse peak time Tp, dicrotic notch time Tn, and pulse reflection index (RI). The four parameters were finally compared between the three subgroups categorized by MaxO2 or by MMVC. In conclusion, it has been demonstrated by quantifying the characteristics of the PPG pulses in different athletes that MaxO2, but not MMVC, had significant effect on the arterial properties. PMID:25710022

  8. Competition and utility financial risks

    SciTech Connect

    Studness, C.M.

    1993-07-01

    While competition for electric utilities has grown steadily for over a decade, the inroads have been small. Utilities have lost load by being forced to buy power from cogenerators. They have foregone some of their normal growth by choosing to buy power from independent power producers instead of building generating facilities themselves. They have absorbed earnings erosion by giving discounts to large industrial customers to avoid having them move production outside their service areas. Yet although competition in these areas can be expected to intensity, the real financial risk for utilities lies on other fronts, principally direct price competition. The type of competition experienced thus far will constrain utility financial progress, but utilities will no doubt find ways to mitigate its impact, an example being investment in demand-side management (DSM) programs. Direct price competition, on the other hand, offers few if any avenues of escape, and it is only a matter of time before the barriers that prevent it are removed. One of the largest is the prohibition of retail wheeling, which is the principal source of price protection for utilities. Significantly, over the course of the last year the prohibition of retail wheeling has been transformed from an untouchable issue into the central issue in the struggle over competition. Price competition, when it develops, will be driven by the cost of producing electric power with new generating facilities and whatever excess generating capacity exists in the industry. How important price competition becomes will depend on what customers want. If low-cost power turns out to be a top priority, price competition will be a very important part of the competitive picture. The experience of industries that have been deregulated, such as the airlines, suggests that low prices will have a high priority.

  9. Home care technology through an ability expectation lens.

    PubMed

    Wolbring, Gregor; Lashewicz, Bonnie

    2014-01-01

    Home care is on the rise, and its delivery is increasingly reliant on an expanding variety of health technologies ranging from computers to telephone "health apps" to social robots. These technologies are most often predicated on expectations that people in their homes (1) can actively interact with these technologies and (2) are willing to submit to the action of the technology in their home. Our purpose is to use an "ability expectations" lens to bring together, and provide some synthesis of, the types of utility and disadvantages that can arise for people with disabilities in relation to home care technology development and use. We searched the academic databases Scopus, Web of Science, EBSCO ALL, IEEE Xplore, and Compendex to collect articles that had the term "home care technology" in the abstract or as a topic (in the case of Web of Science). We also used our background knowledge and related academic literature pertaining to self-diagnosis, health monitoring, companionship, health information gathering, and care. We examined background articles and articles collected through our home care technology search in terms of ability expectations assumed in the presentation of home care technologies, or discussed in relation to home care technologies. While advances in health care support are made possible through emerging technologies, we urge critical examination of such technologies in terms of implications for the rights and dignity of people with diverse abilities. Specifically, we see potential for technologies to result in new forms of exclusion and powerlessness. Ableism influences choices made by funders, policy makers, and the public in the development and use of home health technologies and impacts how people with disabilities are served and how useful health support technologies will be for them. We urge continued critical examination of technology development and use according to ability expectations, and we recommend increasing incorporation of participatory design processes to counteract potential for health support technology to render people with disabilities technologically excluded and powerless. PMID:24956581

  10. Adolescent Expectations of Early Death Predict Adult Risk Behaviors

    PubMed Central

    Nguyen, Quynh C.; Villaveces, Andres; Marshall, Stephen W.; Hussey, Jon M.; Halpern, Carolyn T.; Poole, Charles

    2012-01-01

    Only a handful of public health studies have investigated expectations of early death among adolescents. Associations have been found between these expectations and risk behaviors in adolescence. However, these beliefs may not only predict worse adolescent outcomes, but worse trajectories in health with ties to negative outcomes that endure into young adulthood. The objectives of this study were to investigate perceived chances of living to age 35 (Perceived Survival Expectations, PSE) as a predictor of suicidal ideation, suicide attempt and substance use in young adulthood. We examined the predictive capacity of PSE on future suicidal ideation/attempt after accounting for sociodemographics, depressive symptoms, and history of suicide among family and friends to more fully assess its unique contribution to suicide risk. We investigated the influence of PSE on legal and illegal substance use and varying levels of substance use. We utilized the National Longitudinal Study of Adolescent Health (Add Health) initiated in 199495 among 20,745 adolescents in grades 712 with follow-up interviews in 1996 (Wave II), 200102 (Wave III) and 2008 (Wave IV; ages 2432). Compared to those who were almost certain of living to age 35, perceiving a 5050 or less chance of living to age 35 at Waves I or III predicted suicide attempt and ideation as well as regular substance use (i.e., exceeding daily limits for moderate drinking; smoking ? a pack/day; and using illicit substances other than marijuana at least weekly) at Wave IV. Associations between PSE and detrimental adult outcomes were particularly strong for those reporting persistently low PSE at both Waves I and III. Low PSE at Wave I or Wave III was also related to a doubling and tripling, respectively, of death rates in young adulthood. Long-term and wide-ranging ties between PSE and detrimental outcomes suggest these expectations may contribute to identifying at-risk youth. PMID:22870260

  11. Children's Physical Appearance and Adult Expectations.

    ERIC Educational Resources Information Center

    Feeg, Veronica DeCarolis; Peters, Donald L.

    Caregivers' expectancies and behaviors in relationship to young handicapped children were investigated in this paper. Two studies were conducted in an attempt to answer three questions: (1) How will caregivers respond to the young handicapped child? (2) Do the child's stimulus characteristics, such as physical appearance, create biases in

  12. Attitude towards Mathematics: Emotions, Expectations and Values.

    ERIC Educational Resources Information Center

    Hannula, Markku S.

    2002-01-01

    Suggests a new framework for analyzing attitude and changes in attitude. Identifies four different evaluative processes as aspects of attitude: (1) emotions aroused in the situation; (2) emotions associated with the stimuli; (3) expected consequences; and (4) relating the situation to personal values. Illustrates the usefulness of this analytical…

  13. Effects of Syntactic Expectations on Speech Segmentation

    ERIC Educational Resources Information Center

    Mattys, Sven L.; Melhorn, James F.; White, Laurence

    2007-01-01

    Although the effect of acoustic cues on speech segmentation has been extensively investigated, the role of higher order information (e.g., syntax) has received less attention. Here, the authors examined whether syntactic expectations based on subject-verb agreement have an effect on segmentation and whether they do so despite conflicting acoustic

  14. Starting School: The Importance of Parents' Expectations

    ERIC Educational Resources Information Center

    Russell, Fran

    2005-01-01

    Following the diagnosis of a child's disability parents can find that their expectations are shattered. As they adjust to their new situation they will begin to develop new ideas of what the future will hold. Supporting families is a key theme in current government policy, hence the development of the Early Support Programme. In this paper Fran

  15. Status Valued Goal Objects and Performance Expectations

    ERIC Educational Resources Information Center

    Hysom, Stuart J.

    2009-01-01

    I designed an experiment to test predictions, derived from expectation states theories, that the unequal allocation of social rewards among collective task-focused actors will affect the actors' rates of power and prestige behavior. Past research shows that allocations of exchangeable resources can have these effects. The prediction, however, is

  16. NCAA Penalizes Fewer Teams than Expected

    ERIC Educational Resources Information Center

    Sander, Libby

    2008-01-01

    This article reports that the National Collegiate Athletic Association (NCAA) has penalized fewer teams than it expected this year over athletes' poor academic performance. For years, officials with the NCAA have predicted that strikingly high numbers of college sports teams could be at risk of losing scholarships this year because of their

  17. Linguistic Expectations and Memory Limitations in Reading.

    ERIC Educational Resources Information Center

    Wisher, Robert A.

    This paper discusses a study designed to evaluate the use of semantic and syntactic expectations in reading. Sixteen college-student subjects, measured for reading proficiency by the Nelson-Denny Reading Test, were divided equally into a fast-reading group (350-450 words per minute) and an average-speed reading group (200-275 words per minute).

  18. Bounds for the cumulative conditional expectation function

    SciTech Connect

    Fernández, M.; González-López, V. A.

    2015-03-10

    We introduce the concept of cumulative conditional expectation function. This is a quantity that provides statistical support for making decisions in applied problems. The goal of this paper is to find an analytical expression for upper and lower bounds of this function, assuming stochastic dependence types as being the underlying random structure.

  19. NCAA Penalizes Fewer Teams than Expected

    ERIC Educational Resources Information Center

    Sander, Libby

    2008-01-01

    This article reports that the National Collegiate Athletic Association (NCAA) has penalized fewer teams than it expected this year over athletes' poor academic performance. For years, officials with the NCAA have predicted that strikingly high numbers of college sports teams could be at risk of losing scholarships this year because of their…

  20. How prior expectations shape multisensory perception.

    PubMed

    Gau, Remi; Noppeney, Uta

    2016-01-01

    The brain generates a representation of our environment by integrating signals from a common source, but segregating signals from different sources. This fMRI study investigated how the brain arbitrates between perceptual integration and segregation based on top-down congruency expectations and bottom-up stimulus-bound congruency cues. Participants were presented audiovisual movies of phonologically congruent, incongruent or McGurk syllables that can be integrated into an illusory percept (e.g. "ti" percept for visual ki with auditory /pi/). They reported the syllable they perceived. Critically, we manipulated participants' top-down congruency expectations by presenting McGurk stimuli embedded in blocks of congruent or incongruent syllables. Behaviorally, participants were more likely to fuse audiovisual signals into an illusory McGurk percept in congruent than incongruent contexts. At the neural level, the left inferior frontal sulcus (lIFS) showed increased activations for bottom-up incongruent relative to congruent inputs. Moreover, lIFS activations were increased for physically identical McGurk stimuli, when participants segregated the audiovisual signals and reported their auditory percept. Critically, this activation increase for perceptual segregation was amplified when participants expected audiovisually incongruent signals based on prior sensory experience. Collectively, our results demonstrate that the lIFS combines top-down prior (in)congruency expectations with bottom-up (in)congruency cues to arbitrate between multisensory integration and segregation. PMID:26419391