WorldWideScience

Sample records for random variate generation

  1. Quantum random number generators

    Science.gov (United States)

    Herrero-Collantes, Miguel; Garcia-Escartin, Juan Carlos

    2017-01-01

    Random numbers are a fundamental resource in science and engineering with important applications in simulation and cryptography. The inherent randomness at the core of quantum mechanics makes quantum systems a perfect source of entropy. Quantum random number generation is one of the most mature quantum technologies with many alternative generation methods. This review discusses the different technologies in quantum random number generation from the early devices based on radioactive decay to the multiple ways to use the quantum states of light to gather entropy from a quantum origin. Randomness extraction and amplification and the notable possibility of generating trusted random numbers even with untrusted hardware using device-independent generation protocols are also discussed.

  2. Sunspot random walk and 22-year variation

    Science.gov (United States)

    Love, Jeffrey J.; Rigler, E. Joshua

    2012-01-01

    We examine two stochastic models for consistency with observed long-term secular trends in sunspot number and a faint, but semi-persistent, 22-yr signal: (1) a null hypothesis, a simple one-parameter random-walk model of sunspot-number cycle-to-cycle change, and, (2) an alternative hypothesis, a two-parameter random-walk model with an imposed 22-yr alternating amplitude. The observed secular trend in sunspots, seen from solar cycle 5 to 23, would not be an unlikely result of the accumulation of multiple random-walk steps. Statistical tests show that a 22-yr signal can be resolved in historical sunspot data; that is, the probability is low that it would be realized from random data. On the other hand, the 22-yr signal has a small amplitude compared to random variation, and so it has a relatively small effect on sunspot predictions. Many published predictions for cycle 24 sunspots fall within the dispersion of previous cycle-to-cycle sunspot differences. The probability is low that the Sun will, with the accumulation of random steps over the next few cycles, walk down to a Dalton-like minimum. Our models support published interpretations of sunspot secular variation and 22-yr variation resulting from cycle-to-cycle accumulation of dynamo-generated magnetic energy.

  3. Thermodynamics of random number generation

    Science.gov (United States)

    Aghamohammadi, Cina; Crutchfield, James P.

    2017-06-01

    We analyze the thermodynamic costs of the three main approaches to generating random numbers via the recently introduced Information Processing Second Law. Given access to a specified source of randomness, a random number generator (RNG) produces samples from a desired target probability distribution. This differs from pseudorandom number generators (PRNGs) that use wholly deterministic algorithms and from true random number generators (TRNGs) in which the randomness source is a physical system. For each class, we analyze the thermodynamics of generators based on algorithms implemented as finite-state machines, as these allow for direct bounds on the required physical resources. This establishes bounds on heat dissipation and work consumption during the operation of three main classes of RNG algorithms—including those of von Neumann, Knuth, and Yao and Roche and Hoshi—and for PRNG methods. We introduce a general TRNG and determine its thermodynamic costs exactly for arbitrary target distributions. The results highlight the significant differences between the three main approaches to random number generation: One is work producing, one is work consuming, and the other is potentially dissipation neutral. Notably, TRNGs can both generate random numbers and convert thermal energy to stored work. These thermodynamic costs on information creation complement Landauer's limit on the irreducible costs of information destruction.

  4. Random Process Generation.

    Science.gov (United States)

    1980-06-01

    Address: Professor Bruce W. Schmeiser School of Industrial Engineering Purdue University West Lafayette, IN 47907 UjDISTIUMUTIO" TTMJ Approved for...algorithms developed under this contract are about twice as fast as the best alternatives available today. Peter Lewis at the Naval Postgraduate School ...generating bivariate gazua vectors. These algorithms are the only methods available which are valid for an gaia marginal distributions and j 6 -. . 4

  5. Generating Realistic Labelled, Weighted Random Graphs

    CERN Document Server

    Davis, Michael Charles; Liu, Weiru; Miller, Paul; Hunter, Ruth; Kee, Frank

    2015-01-01

    Generative algorithms for random graphs have yielded insights into the structure and evolution of real-world networks. Most networks exhibit a well-known set of properties, such as heavy-tailed degree distributions, clustering and community formation. Usually, random graph models consider only structural information, but many real-world networks also have labelled vertices and weighted edges. In this paper, we present a generative model for random graphs with discrete vertex labels and numeric edge weights. The weights are represented as a set of Beta Mixture Models (BMMs) with an arbitrary number of mixtures, which are learned from real-world networks. We propose a Bayesian Variational Inference (VI) approach, which yields an accurate estimation while keeping computation times tractable. We compare our approach to state-of-the-art random labelled graph generators and an earlier approach based on Gaussian Mixture Models (GMMs). Our results allow us to draw conclusions about the contribution of vertex labels a...

  6. Generating random networks and graphs

    CERN Document Server

    Coolen, Ton; Roberts, Ekaterina

    2017-01-01

    This book supports researchers who need to generate random networks, or who are interested in the theoretical study of random graphs. The coverage includes exponential random graphs (where the targeted probability of each network appearing in the ensemble is specified), growth algorithms (i.e. preferential attachment and the stub-joining configuration model), special constructions (e.g. geometric graphs and Watts Strogatz models) and graphs on structured spaces (e.g. multiplex networks). The presentation aims to be a complete starting point, including details of both theory and implementation, as well as discussions of the main strengths and weaknesses of each approach. It includes extensive references for readers wishing to go further. The material is carefully structured to be accessible to researchers from all disciplines while also containing rigorous mathematical analysis (largely based on the techniques of statistical mechanics) to support those wishing to further develop or implement the theory of rand...

  7. Generating Realistic Labelled, Weighted Random Graphs

    Directory of Open Access Journals (Sweden)

    Michael Charles Davis

    2015-12-01

    Full Text Available Generative algorithms for random graphs have yielded insights into the structure and evolution of real-world networks. Most networks exhibit a well-known set of properties, such as heavy-tailed degree distributions, clustering and community formation. Usually, random graph models consider only structural information, but many real-world networks also have labelled vertices and weighted edges. In this paper, we present a generative model for random graphs with discrete vertex labels and numeric edge weights. The weights are represented as a set of Beta Mixture Models (BMMs with an arbitrary number of mixtures, which are learned from real-world networks. We propose a Bayesian Variational Inference (VI approach, which yields an accurate estimation while keeping computation times tractable. We compare our approach to state-of-the-art random labelled graph generators and an earlier approach based on Gaussian Mixture Models (GMMs. Our results allow us to draw conclusions about the contribution of vertex labels and edge weights to graph structure.

  8. Self-correcting random number generator

    Energy Technology Data Exchange (ETDEWEB)

    Humble, Travis S.; Pooser, Raphael C.

    2016-09-06

    A system and method for generating random numbers. The system may include a random number generator (RNG), such as a quantum random number generator (QRNG) configured to self-correct or adapt in order to substantially achieve randomness from the output of the RNG. By adapting, the RNG may generate a random number that may be considered random regardless of whether the random number itself is tested as such. As an example, the RNG may include components to monitor one or more characteristics of the RNG during operation, and may use the monitored characteristics as a basis for adapting, or self-correcting, to provide a random number according to one or more performance criteria.

  9. Analysis of android random number generator

    OpenAIRE

    Sarıtaş, Serkan

    2013-01-01

    Ankara : The Department of Computer Engineering and the Graduate School of Engineering and Science of Bilkent University, 2013. Thesis (Master's) -- Bilkent University, 2013. Includes bibliographical references leaves 61-65. Randomness is a crucial resource for cryptography, and random number generators are critical building blocks of almost all cryptographic systems. Therefore, random number generation is one of the key parts of secure communication. Random number generatio...

  10. Variational Infinite Hidden Conditional Random Fields.

    Science.gov (United States)

    Bousmalis, Konstantinos; Zafeiriou, Stefanos; Morency, Louis-Philippe; Pantic, Maja; Ghahramani, Zoubin

    2015-09-01

    Hidden conditional random fields (HCRFs) are discriminative latent variable models which have been shown to successfully learn the hidden structure of a given classification problem. An Infinite hidden conditional random field is a hidden conditional random field with a countably infinite number of hidden states, which rids us not only of the necessity to specify a priori a fixed number of hidden states available but also of the problem of overfitting. Markov chain Monte Carlo (MCMC) sampling algorithms are often employed for inference in such models. However, convergence of such algorithms is rather difficult to verify, and as the complexity of the task at hand increases the computational cost of such algorithms often becomes prohibitive. These limitations can be overcome by variational techniques. In this paper, we present a generalized framework for infinite HCRF models, and a novel variational inference approach on a model based on coupled Dirichlet Process Mixtures, the HCRF-DPM. We show that the variational HCRF-DPM is able to converge to a correct number of represented hidden states, and performs as well as the best parametric HCRFs-chosen via cross-validation-for the difficult tasks of recognizing instances of agreement, disagreement, and pain in audiovisual sequences.

  11. Source-Independent Quantum Random Number Generation

    Science.gov (United States)

    Cao, Zhu; Zhou, Hongyi; Yuan, Xiao; Ma, Xiongfeng

    2016-01-01

    Quantum random number generators can provide genuine randomness by appealing to the fundamental principles of quantum mechanics. In general, a physical generator contains two parts—a randomness source and its readout. The source is essential to the quality of the resulting random numbers; hence, it needs to be carefully calibrated and modeled to achieve information-theoretical provable randomness. However, in practice, the source is a complicated physical system, such as a light source or an atomic ensemble, and any deviations in the real-life implementation from the theoretical model may affect the randomness of the output. To close this gap, we propose a source-independent scheme for quantum random number generation in which output randomness can be certified, even when the source is uncharacterized and untrusted. In our randomness analysis, we make no assumptions about the dimension of the source. For instance, multiphoton emissions are allowed in optical implementations. Our analysis takes into account the finite-key effect with the composable security definition. In the limit of large data size, the length of the input random seed is exponentially small compared to that of the output random bit. In addition, by modifying a quantum key distribution system, we experimentally demonstrate our scheme and achieve a randomness generation rate of over 5 ×103 bit /s .

  12. Random Number Generators in Secure Disk Drives

    Directory of Open Access Journals (Sweden)

    Hars Laszlo

    2009-01-01

    Full Text Available Abstract Cryptographic random number generators seeded by physical entropy sources are employed in many embedded security systems, including self-encrypting disk drives, being manufactured by the millions every year. Random numbers are used for generating encryption keys and for facilitating secure communication, and they are also provided to users for their applications. We discuss common randomness requirements, techniques for estimating the entropy of physical sources, investigate specific nonrandom physical properties, estimate the autocorrelation, then mix reduce the data until all common randomness tests pass. This method is applied to a randomness source in disk drives: the always changing coefficients of an adaptive filter for the read channel equalization. These coefficients, affected by many kinds of physical noise, are used in the reseeding process of a cryptographic pseudorandom number generator in a family of self encrypting disk drives currently in the market.

  13. A Hybrid Random Number Generator(HRNG

    Directory of Open Access Journals (Sweden)

    Osvaldo Skliar

    2011-07-01

    Full Text Available The purpose of this paper is to present a novel Hybrid Random Number Generator (HRNG. Here “hybrid” refers to the fact that to construct this generator it is necessary to use 1physical components – texts – and a physical process, and 2 a mathematical procedure. This HRNG makes it possible to generate genuine random numbers which may be used both for computer simulation of probabilistic systems and in the field of cryptography. The results of a comparative study of the binary strings generated by this HRNG and of those generated by two highly used implementations of a congruential algorithm designed to generate pseudorandom numbers are given here. One of the latter is the implementation incorporated into the Java 2 platform (version 1.6, and the other is the implementation incorporated into the runtime library of Microsoft’s Visual C++ 2008 compiler.

  14. Pseudo-random number generator based on asymptotic deterministic randomness

    Energy Technology Data Exchange (ETDEWEB)

    Wang Kai [Department of Radio Engineering, Southeast University, Nanjing (China)], E-mail: kaiwang@seu.edu.cn; Pei Wenjiang; Xia Haishan [Department of Radio Engineering, Southeast University, Nanjing (China); Cheung Yiuming [Department of Computer Science, Hong Kong Baptist University, Hong Kong (China)

    2008-06-09

    A novel approach to generate the pseudorandom-bit sequence from the asymptotic deterministic randomness system is proposed in this Letter. We study the characteristic of multi-value correspondence of the asymptotic deterministic randomness constructed by the piecewise linear map and the noninvertible nonlinearity transform, and then give the discretized systems in the finite digitized state space. The statistic characteristics of the asymptotic deterministic randomness are investigated numerically, such as stationary probability density function and random-like behavior. Furthermore, we analyze the dynamics of the symbolic sequence. Both theoretical and experimental results show that the symbolic sequence of the asymptotic deterministic randomness possesses very good cryptographic properties, which improve the security of chaos based PRBGs and increase the resistance against entropy attacks and symbolic dynamics attacks.

  15. Variational data assimilation using targetted random walks

    KAUST Repository

    Cotter, S. L.

    2011-02-15

    The variational approach to data assimilation is a widely used methodology for both online prediction and for reanalysis. In either of these scenarios, it can be important to assess uncertainties in the assimilated state. Ideally, it is desirable to have complete information concerning the Bayesian posterior distribution for unknown state given data. We show that complete computational probing of this posterior distribution is now within the reach in the offline situation. We introduce a Markov chain-Monte Carlo (MCMC) method which enables us to directly sample from the Bayesian posterior distribution on the unknown functions of interest given observations. Since we are aware that these methods are currently too computationally expensive to consider using in an online filtering scenario, we frame this in the context of offline reanalysis. Using a simple random walk-type MCMC method, we are able to characterize the posterior distribution using only evaluations of the forward model of the problem, and of the model and data mismatch. No adjoint model is required for the method we use; however, more sophisticated MCMC methods are available which exploit derivative information. For simplicity of exposition, we consider the problem of assimilating data, either Eulerian or Lagrangian, into a low Reynolds number flow in a two-dimensional periodic geometry. We will show that in many cases it is possible to recover the initial condition and model error (which we describe as unknown forcing to the model) from data, and that with increasing amounts of informative data, the uncertainty in our estimations reduces. © 2011 John Wiley & Sons, Ltd.

  16. Variational Infinite Hidden Conditional Random Fields

    NARCIS (Netherlands)

    Bousmalis, Konstantinos; Zafeiriou, Stefanos; Morency, Louis-Philippe; Pantic, Maja; Ghahramani, Zoubin

    2015-01-01

    Hidden conditional random fields (HCRFs) are discriminative latent variable models which have been shown to successfully learn the hidden structure of a given classification problem. An Infinite hidden conditional random field is a hidden conditional random field with a countably infinite number of

  17. Fast Generation of Discrete Random Variables

    Directory of Open Access Journals (Sweden)

    George Marsaglia

    2004-07-01

    Full Text Available We describe two methods and provide C programs for generating discrete random variables with functions that are simple and fast, averaging ten times as fast as published methods and more than five times as fast as the fastest of those. We provide general procedures for implementing the two methods, as well as specific procedures for three of the most important discrete distributions: Poisson, binomial and hypergeometric.

  18. Physical Principle for Generation of Randomness

    Science.gov (United States)

    Zak, Michail

    2009-01-01

    A physical principle (more precisely, a principle that incorporates mathematical models used in physics) has been conceived as the basis of a method of generating randomness in Monte Carlo simulations. The principle eliminates the need for conventional random-number generators. The Monte Carlo simulation method is among the most powerful computational methods for solving high-dimensional problems in physics, chemistry, economics, and information processing. The Monte Carlo simulation method is especially effective for solving problems in which computational complexity increases exponentially with dimensionality. The main advantage of the Monte Carlo simulation method over other methods is that the demand on computational resources becomes independent of dimensionality. As augmented by the present principle, the Monte Carlo simulation method becomes an even more powerful computational method that is especially useful for solving problems associated with dynamics of fluids, planning, scheduling, and combinatorial optimization. The present principle is based on coupling of dynamical equations with the corresponding Liouville equation. The randomness is generated by non-Lipschitz instability of dynamics triggered and controlled by feedback from the Liouville equation. (In non-Lipschitz dynamics, the derivatives of solutions of the dynamical equations are not required to be bounded.)

  19. Employing online quantum random number generators for generating truly random quantum states in Mathematica

    Science.gov (United States)

    Miszczak, Jarosław Adam

    2013-01-01

    The presented package for the Mathematica computing system allows the harnessing of quantum random number generators (QRNG) for investigating the statistical properties of quantum states. The described package implements a number of functions for generating random states. The new version of the package adds the ability to use the on-line quantum random number generator service and implements new functions for retrieving lists of random numbers. Thanks to the introduced improvements, the new version provides faster access to high-quality sources of random numbers and can be used in simulations requiring large amount of random data. New version program summaryProgram title: TRQS Catalogue identifier: AEKA_v2_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEKA_v2_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 18 134 No. of bytes in distributed program, including test data, etc.: 2 520 49 Distribution format: tar.gz Programming language: Mathematica, C. Computer: Any supporting Mathematica in version 7 or higher. Operating system: Any platform supporting Mathematica; tested with GNU/Linux (32 and 64 bit). RAM: Case-dependent Supplementary material: Fig. 1 mentioned below can be downloaded. Classification: 4.15. External routines: Quantis software library (http://www.idquantique.com/support/quantis-trng.html) Catalogue identifier of previous version: AEKA_v1_0 Journal reference of previous version: Comput. Phys. Comm. 183(2012)118 Does the new version supersede the previous version?: Yes Nature of problem: Generation of random density matrices and utilization of high-quality random numbers for the purpose of computer simulation. Solution method: Use of a physical quantum random number generator and an on-line service providing access to the source of true random

  20. Nucleosomal promoter variation generates gene expression noise.

    Science.gov (United States)

    Brown, Christopher R; Boeger, Hinrich

    2014-12-16

    Gene product molecule numbers fluctuate over time and between cells, confounding deterministic expectations. The molecular origins of this noise of gene expression remain unknown. Recent EM analysis of single PHO5 gene molecules of yeast indicated that promoter molecules stochastically assume alternative nucleosome configurations at steady state, including the fully nucleosomal and nucleosome-free configuration. Given that distinct configurations are unequally conducive to transcription, the nucleosomal variation of promoter molecules may constitute a source of gene expression noise. This notion, however, implies an untested conjecture, namely that the nucleosomal variation arises de novo or intrinsically (i.e., that it cannot be explained as the result of the promoter's deterministic response to variation in its molecular surroundings). Here, we show--by microscopically analyzing the nucleosome configurations of two juxtaposed physically linked PHO5 promoter copies--that the configurational variation, indeed, is intrinsically stochastic and thus, a cause of gene expression noise rather than its effect.

  1. Random Numbers Generated from Audio and Video Sources

    Directory of Open Access Journals (Sweden)

    I-Te Chen

    2013-01-01

    Full Text Available Random numbers are very useful in simulation, chaos theory, game theory, information theory, pattern recognition, probability theory, quantum mechanics, statistics, and statistical mechanics. The random numbers are especially helpful in cryptography. In this work, the proposed random number generators come from white noise of audio and video (A/V sources which are extracted from high-resolution IPCAM, WEBCAM, and MPEG-1 video files. The proposed generator applied on video sources from IPCAM and WEBCAM with microphone would be the true random number generator and the pseudorandom number generator when applied on video sources from MPEG-1 video file. In addition, when applying NIST SP 800-22 Rev.1a 15 statistics tests on the random numbers generated from the proposed generator, around 98% random numbers can pass 15 statistical tests. Furthermore, the audio and video sources can be found easily; hence, the proposed generator is a qualified, convenient, and efficient random number generator.

  2. Nonquadratic Variation of the Blum Blum Shub Pseudorandom Number Generator

    Science.gov (United States)

    2016-09-01

    the use of random numbers. For this rea- son, cryptographers design pseudorandom number generators (PRNG) as a method of generating random numbers...fails the block frequency test, as it is clearly not random . 3.3.3 Runs Test A run is defined as a series of either 1’s or 0’s in a row. The purpose of...that would be expected of a random sequence. The NIST standard uses three common block sizes for this test, M = 8, 128, and 10, 000. The test divides

  3. Unbiased All-Optical Random-Number Generator

    OpenAIRE

    Tobias Steinle; Greiner, Johannes N.; Jörg Wrachtrup; Harald Giessen; Ilja Gerhardt

    2017-01-01

    The generation of random bits is of enormous importance in modern information science. Cryptographic security is based on random numbers which require a physical process for their generation. This is commonly performed by hardware random number generators. These exhibit often a number of problems, namely experimental bias, memory in the system, and other technical subtleties, which reduce the reliability in the entropy estimation. Further, the generated outcome has to be post-processed to "ir...

  4. High-speed true random number generation based on paired memristors for security electronics

    Science.gov (United States)

    Zhang, Teng; Yin, Minghui; Xu, Changmin; Lu, Xiayan; Sun, Xinhao; Yang, Yuchao; Huang, Ru

    2017-11-01

    True random number generator (TRNG) is a critical component in hardware security that is increasingly important in the era of mobile computing and internet of things. Here we demonstrate a TRNG using intrinsic variation of memristors as a natural source of entropy that is otherwise undesirable in most applications. The random bits were produced by cyclically switching a pair of tantalum oxide based memristors and comparing their resistance values in the off state, taking advantage of the more pronounced resistance variation compared with that in the on state. Using an alternating read scheme in the designed TRNG circuit, the unbiasedness of the random numbers was significantly improved, and the bitstream passed standard randomness tests. The Pt/TaO x /Ta memristors fabricated in this work have fast programming/erasing speeds of ∼30 ns, suggesting a high random number throughput. The approach proposed here thus holds great promise for physically-implemented random number generation.

  5. Ternary jitter-based true random number generator

    Science.gov (United States)

    Latypov, Rustam; Stolov, Evgeni

    2017-01-01

    In this paper a novel family of generators producing true uniform random numbers in ternary logic is presented. The generator consists of a number of identical ternary logic combinational units connected into a ring. All the units are provided to have a random delay time, and this time is supposed to be distributed in accordance with an exponential distribution. All delays are supposed to be independent events. The theory of the generator is based on Erlang equations. The generator can be used for test production in various systems. Features of multidimensional random vectors, produced by the generator, are discussed.

  6. Manifolds in random media: beyond the variational approximation

    Science.gov (United States)

    Goldschmidt, Yadin Y.

    1994-01-01

    In this paper we give a closed form expression for the 1/d corrections to the selfenergy characterizing the correlation function of a manifold in random media. This amounts to the first confection beyond the variational approximation. At this time we were able to evaluate these corrections in the high temperature "phase" of the notorious toy-model describing a classical particle subject to the influence of both a harmonic potential and a random potential. Although in this phase the correct solution is replica symmetric the calculation is non-trivial. The outcome is compared with previous analytical and numerical results. The corrections diverge at the "transition" temperature.

  7. Random noise attenuation using an improved anisotropic total variation regularization

    Science.gov (United States)

    Gemechu, Diriba; Yuan, Huan; Ma, Jianwei

    2017-09-01

    In seismic data processing, attenuation of random noise from the observed data is the basic step which improves the signal-to-noise ratio (SNR) of seismic data. In this paper, we proposed an anisotropic total bounded variation regularization approach to attenuate noise. An improved constraint convex optimization model is formulated for this approach and then the split Bregman algorithm is used to solve the optimization model. Generalized cross validation (GCV) technique is used to estimate the regularization parameter. Synthetic and real seismic data are considered to show the out performance of the proposed method in terms of event-preserving denoising, in comparison with FX deconvolution, shearlet hard thresholding, and anisotropic total variation methods. The numerical results indicate that the proposed method effectively attenuates random noise by preserving the structure and important features of seismic data.

  8. Random number datasets generated from statistical analysis of randomly sampled GSM recharge cards.

    Science.gov (United States)

    Okagbue, Hilary I; Opanuga, Abiodun A; Oguntunde, Pelumi E; Ugwoke, Paulinus O

    2017-02-01

    In this article, a random number of datasets was generated from random samples of used GSM (Global Systems for Mobile Communications) recharge cards. Statistical analyses were performed to refine the raw data to random number datasets arranged in table. A detailed description of the method and relevant tests of randomness were also discussed.

  9. Quantum Random Number Generation on a Mobile Phone

    Directory of Open Access Journals (Sweden)

    Bruno Sanguinetti

    2014-09-01

    Full Text Available Quantum random number generators (QRNGs can significantly improve the security of cryptographic protocols by ensuring that generated keys cannot be predicted. However, the cost, size, and power requirements of current Quantum random number generators have prevented them from becoming widespread. In the meantime, the quality of the cameras integrated in mobile telephones has improved significantly so that now they are sensitive to light at the few-photon level. We demonstrate how these can be used to generate random numbers of a quantum origin.

  10. SPRNG Scalable Parallel Random Number Generator LIbrary

    Energy Technology Data Exchange (ETDEWEB)

    2010-03-16

    This revision corrects some errors in SPRNG 1. Users of newer SPRNG versions can obtain the corrected files and build their version with it. This version also improves the scalability of some of the application-based tests in the SPRNG test suite. It also includes an interface to a parallel Mersenne Twister, so that if users install the Mersenne Twister, then they can test this generator with the SPRNG test suite and also use some SPRNG features with that generator.

  11. Humans cannot consciously generate random numbers sequences: Polemic study.

    Science.gov (United States)

    Figurska, Małgorzata; Stańczyk, Maciej; Kulesza, Kamil

    2008-01-01

    It is widely believed, that randomness exists in Nature. In fact such an assumption underlies many scientific theories and is embedded in the foundations of quantum mechanics. Assuming that this hypothesis is valid one can use natural phenomena, like radioactive decay, to generate random numbers. Today, computers are capable of generating the so-called pseudorandom numbers. Such series of numbers are only seemingly random (bias in the randomness quality can be observed). Question whether people can produce random numbers, has been investigated by many scientists in the recent years. The paper "Humans can consciously generate random numbers sequences..." published recently in Medical Hypotheses made claims that were in many ways contrary to state of art; it also stated far-reaching hypotheses. So, we decided to repeat the experiments reported, with special care being taken of proper laboratory procedures. Here, we present the results and discuss possible implications in computer and other sciences.

  12. Generating log-normally distributed random numbers by using the Ziggurat algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jong Soo [KINS, Daejeon (Korea, Republic of)

    2016-05-15

    Uncertainty analyses are usually based on the Monte Carlo method. Using an efficient random number generator(RNG) is a key element in success of Monte Carlo simulations. Log-normal distributed variates are very typical in NPP PSAs. This paper proposes an approach to generate log normally distributed variates based on the Ziggurat algorithm and evaluates the efficiency of the proposed Ziggurat RNG. The proposed RNG can be helpful to improve the uncertainty analysis of NPP PSAs. This paper focuses on evaluating the efficiency of the Ziggurat algorithm from a NPP PSA point of view. From this study, we can draw the following conclusions. - The Ziggurat algorithm is one of perfect random number generators to product normal distributed variates. - The Ziggurat algorithm is computationally much faster than the most commonly used method, Marsaglia polar method.

  13. Analysis of Additive Random Number Generators.

    Science.gov (United States)

    1977-03-01

    CLASSIFICATION OF THIS PAGE (When Data Entered; I .,.,•• n .„^iMl~^.-». H .,il~l.*...,...-•..,.,.., • 1 ——’"- •"•’ ANALYSIS OF ADDITIVE RANDOM...among my teachers two of the best: my parents, Bil and Marleen Reiser. - , i — - •- - J I " ii. .1 I l. Kl U...the period, we know that r(pa*z) * pr(pa) and k - • - ----• •--- - -— — ...., . H ..J 1-..11.111 ’ Introduction that r(pa *’) divides

  14. Experimental measurement-device-independent quantum random-number generation

    Science.gov (United States)

    Nie, You-Qi; Guan, Jian-Yu; Zhou, Hongyi; Zhang, Qiang; Ma, Xiongfeng; Zhang, Jun; Pan, Jian-Wei

    2016-12-01

    The randomness from a quantum random-number generator (QRNG) relies on the accurate characterization of its devices. However, device imperfections and inaccurate characterizations can result in wrong entropy estimation and bias in practice, which highly affects the genuine randomness generation and may even induce the disappearance of quantum randomness in an extreme case. Here we experimentally demonstrate a measurement-device-independent (MDI) QRNG based on time-bin encoding to achieve certified quantum randomness even when the measurement devices are uncharacterized and untrusted. The MDI-QRNG is randomly switched between the regular randomness generation mode and a test mode, in which four quantum states are randomly prepared to perform measurement tomography in real time. With a clock rate of 25 MHz, the MDI-QRNG generates a final random bit rate of 5.7 kbps. Such implementation with an all-fiber setup provides an approach to construct a fully integrated MDI-QRNG with trusted but error-prone devices in practice.

  15. Unbiased All-Optical Random-Number Generator

    Science.gov (United States)

    Steinle, Tobias; Greiner, Johannes N.; Wrachtrup, Jörg; Giessen, Harald; Gerhardt, Ilja

    2017-10-01

    The generation of random bits is of enormous importance in modern information science. Cryptographic security is based on random numbers which require a physical process for their generation. This is commonly performed by hardware random-number generators. These often exhibit a number of problems, namely experimental bias, memory in the system, and other technical subtleties, which reduce the reliability in the entropy estimation. Further, the generated outcome has to be postprocessed to "iron out" such spurious effects. Here, we present a purely optical randomness generator, based on the bistable output of an optical parametric oscillator. Detector noise plays no role and postprocessing is reduced to a minimum. Upon entering the bistable regime, initially the resulting output phase depends on vacuum fluctuations. Later, the phase is rigidly locked and can be well determined versus a pulse train, which is derived from the pump laser. This delivers an ambiguity-free output, which is reliably detected and associated with a binary outcome. The resulting random bit stream resembles a perfect coin toss and passes all relevant randomness measures. The random nature of the generated binary outcome is furthermore confirmed by an analysis of resulting conditional entropies.

  16. Unbiased All-Optical Random-Number Generator

    Directory of Open Access Journals (Sweden)

    Tobias Steinle

    2017-11-01

    Full Text Available The generation of random bits is of enormous importance in modern information science. Cryptographic security is based on random numbers which require a physical process for their generation. This is commonly performed by hardware random-number generators. These often exhibit a number of problems, namely experimental bias, memory in the system, and other technical subtleties, which reduce the reliability in the entropy estimation. Further, the generated outcome has to be postprocessed to “iron out” such spurious effects. Here, we present a purely optical randomness generator, based on the bistable output of an optical parametric oscillator. Detector noise plays no role and postprocessing is reduced to a minimum. Upon entering the bistable regime, initially the resulting output phase depends on vacuum fluctuations. Later, the phase is rigidly locked and can be well determined versus a pulse train, which is derived from the pump laser. This delivers an ambiguity-free output, which is reliably detected and associated with a binary outcome. The resulting random bit stream resembles a perfect coin toss and passes all relevant randomness measures. The random nature of the generated binary outcome is furthermore confirmed by an analysis of resulting conditional entropies.

  17. Variational Calculation of Effective Parameters in Random Porous Media

    Science.gov (United States)

    Hristopulos, Dionissios T.; Christakos, George

    1998-03-01

    Effective parameters are used in stochastic hydrology and petroleum engineering as estimates of the coarse-grained behavior of fluid flow and transport. Stochastic effective parameter estimation involves averaging over the local heterogeneity. Explicit evaluation methods are often based on low order perturbation expansions. We obtain more general estimates using a variational scheme that employs auxiliary probability measures. The average over the local fluctuations is evaluated by means of the logarithm transform and the replica trick. The equations satisfied by the effective parameters are obtained variationally from an effective free energy functional. We use this method for the evaluation of the effective permeability of random porous media with Gaussian local fluctuations. The resulting equations are solved explicitly in specific cases, and the results are compared with leading-order perturbation estimates and experimental data. Explicit finite-size expressions are obtained using momentum-space filters. The implications of the finite size behavior for the scaleup problem are discussed.

  18. Streaming Algorithms for Optimal Generation of Random Bits

    OpenAIRE

    Zhou, Hongchao; Bruck, Jehoshua

    2012-01-01

    Generating random bits from a source of biased coins (the biased is unknown) is a classical question that was originally studied by von Neumann. There are a number of known algorithms that have asymptotically optimal information efficiency, namely, the expected number of generated random bits per input bit is asymptotically close to the entropy of the source. However, only the original von Neumann algorithm has a 'streaming property' - it operates on a single input bit at a time and it genera...

  19. Random Number Generation for Petascale Quantum Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Ashok Srinivasan

    2010-03-16

    The quality of random number generators can affect the results of Monte Carlo computations, especially when a large number of random numbers are consumed. Furthermore, correlations present between different random number streams in a parallel computation can further affect the results. The SPRNG software, which the author had developed earlier, has pseudo-random number generators (PRNGs) capable of producing large numbers of streams with large periods. However, they had been empirically tested on only thousand streams earlier. In the work summarized here, we tested the SPRNG generators with over a hundred thousand streams, involving over 10^14 random numbers per test, on some tests. We also tested the popular Mersenne Twister. We believe that these are the largest tests of PRNGs, both in terms of the numbers of streams tested and the number of random numbers tested. We observed defects in some of these generators, including the Mersenne Twister, while a few generators appeared to perform well. We also corrected an error in the implementation of one of the SPRNG generators.

  20. Using chaos to generate variations on movement sequences

    Science.gov (United States)

    Bradley, Elizabeth; Stuart, Joshua

    1998-12-01

    We describe a method for introducing variations into predefined motion sequences using a chaotic symbol-sequence reordering technique. A progression of symbols representing the body positions in a dance piece, martial arts form, or other motion sequence is mapped onto a chaotic trajectory, establishing a symbolic dynamics that links the movement sequence and the attractor structure. A variation on the original piece is created by generating a trajectory with slightly different initial conditions, inverting the mapping, and using special corpus-based graph-theoretic interpolation schemes to smooth any abrupt transitions. Sensitive dependence guarantees that the variation is different from the original; the attractor structure and the symbolic dynamics guarantee that the two resemble one another in both aesthetic and mathematical senses.

  1. Random matrix approach to the dynamics of stock inventory variations

    Science.gov (United States)

    Zhou, Wei-Xing; Mu, Guo-Hua; Kertész, János

    2012-09-01

    It is well accepted that investors can be classified into groups owing to distinct trading strategies, which forms the basic assumption of many agent-based models for financial markets when agents are not zero-intelligent. However, empirical tests of these assumptions are still very rare due to the lack of order flow data. Here we adopt the order flow data of Chinese stocks to tackle this problem by investigating the dynamics of inventory variations for individual and institutional investors that contain rich information about the trading behavior of investors and have a crucial influence on price fluctuations. We find that the distributions of cross-correlation coefficient Cij have power-law forms in the bulk that are followed by exponential tails, and there are more positive coefficients than negative ones. In addition, it is more likely that two individuals or two institutions have a stronger inventory variation correlation than one individual and one institution. We find that the largest and the second largest eigenvalues (λ1 and λ2) of the correlation matrix cannot be explained by random matrix theory and the projections of investors' inventory variations on the first eigenvector u(λ1) are linearly correlated with stock returns, where individual investors play a dominating role. The investors are classified into three categories based on the cross-correlation coefficients CV R between inventory variations and stock returns. A strong Granger causality is unveiled from stock returns to inventory variations, which means that a large proportion of individuals hold the reversing trading strategy and a small part of individuals hold the trending strategy. Our empirical findings have scientific significance in the understanding of investors' trading behavior and in the construction of agent-based models for emerging stock markets.

  2. The Reliability of Randomly Generated Math Curriculum-Based Measurements

    Science.gov (United States)

    Strait, Gerald G.; Smith, Bradley H.; Pender, Carolyn; Malone, Patrick S.; Roberts, Jarod; Hall, John D.

    2015-01-01

    "Curriculum-Based Measurement" (CBM) is a direct method of academic assessment used to screen and evaluate students' skills and monitor their responses to academic instruction and intervention. Interventioncentral.org offers a math worksheet generator at no cost that creates randomly generated "math curriculum-based measures"…

  3. Generation of Random Numbers and Parallel Random Number Streams for Monte Carlo Simulations

    Directory of Open Access Journals (Sweden)

    L. Yu. Barash

    2012-01-01

    Full Text Available Modern methods and libraries for high quality pseudorandom number generation and for generation of parallel random number streams for Monte Carlo simulations are considered. The probability equidistribution property and the parameters when the property holds at dimensions up to logarithm of mesh size are considered for Multiple Recursive Generators.

  4. Brain potentials index executive functions during random number generation.

    Science.gov (United States)

    Joppich, Gregor; Däuper, Jan; Dengler, Reinhard; Johannes, Sönke; Rodriguez-Fornells, Antoni; Münte, Thomas F

    2004-06-01

    The generation of random sequences is considered to tax different executive functions. To explore the involvement of these functions further, brain potentials were recorded in 16 healthy young adults while either engaging in random number generation (RNG) by pressing the number keys on a computer keyboard in a random sequence or in ordered number generation (ONG) necessitating key presses in the canonical order. Key presses were paced by an external auditory stimulus to yield either fast (1 press/800 ms) or slow (1 press/1300 ms) sequences in separate runs. Attentional demands of random and ordered tasks were assessed by the introduction of a secondary task (key-press to a target tone). The P3 amplitude to the target tone of this secondary task was reduced during RNG, reflecting the greater consumption of attentional resources during RNG. Moreover, RNG led to a left frontal negativity peaking 140 ms after the onset of the pacing stimulus, whenever the subjects produced a true random response. This negativity could be attributed to the left dorsolateral prefrontal cortex and was absent when numbers were repeated. This negativity was interpreted as an index for the inhibition of habitual responses. Finally, in response locked ERPs a negative component was apparent peaking about 50 ms after the key-press that was more prominent during RNG. Source localization suggested a medial frontal source. This effect was tentatively interpreted as a reflection of the greater monitoring demands during random sequence generation.

  5. Efficient Raman generation in a waveguide: A route to ultrafast quantum random number generation

    Energy Technology Data Exchange (ETDEWEB)

    England, D. G.; Bustard, P. J.; Moffatt, D. J.; Nunn, J.; Lausten, R.; Sussman, B. J., E-mail: ben.sussman@nrc.ca [National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada)

    2014-02-03

    The inherent uncertainty in quantum mechanics offers a source of true randomness which can be used to produce unbreakable cryptographic keys. We discuss the development of a high-speed random number generator based on the quantum phase fluctuations in spontaneously initiated stimulated Raman scattering (SISRS). We utilize the tight confinement and long interaction length available in a Potassium Titanyl Phosphate waveguide to generate highly efficient SISRS using nanojoule pulse energies, reducing the high pump power requirements of the previous approaches. We measure the random phase of the Stokes output using a simple interferometric setup to yield quantum random numbers at 145 Mbps.

  6. Seismic random noise attenuation using shearlet and total generalized variation

    Science.gov (United States)

    Kong, Dehui; Peng, Zhenming

    2015-12-01

    Seismic denoising from a corrupted observation is an important part of seismic data processing which improves the signal-to-noise ratio (SNR) and resolution. In this paper, we present an effective denoising method to attenuate seismic random noise. The method takes advantage of shearlet and total generalized variation (TGV) regularization. Different regularity levels of TGV improve the quality of the final result by suppressing Gibbs artifacts caused by the shearlet. The problem is formulated as mixed constraints in a convex optimization. A Bregman algorithm is proposed to solve the proposed model. Extensive experiments based on one synthetic datum and two post-stack field data are done to compare performance. The results demonstrate that the proposed method provides superior effectiveness and preserve the structure better.

  7. Chaos-based Pseudo-random Number Generation

    KAUST Repository

    Barakat, Mohamed L.

    2014-04-10

    Various methods and systems related to chaos-based pseudo-random number generation are presented. In one example, among others, a system includes a pseudo-random number generator (PRNG) to generate a series of digital outputs and a nonlinear post processing circuit to perform an exclusive OR (XOR) operation on a first portion of a current digital output of the PRNG and a permutated version of a corresponding first portion of a previous post processed output to generate a corresponding first portion of a current post processed output. In another example, a method includes receiving at least a first portion of a current output from a PRNG and performing an XOR operation on the first portion of the current PRNG output with a permutated version of a corresponding first portion of a previous post processed output to generate a corresponding first portion of a current post processed output.

  8. Random generation of RNA secondary structures according to native distributions

    Directory of Open Access Journals (Sweden)

    Nebel Markus E

    2011-10-01

    Full Text Available Abstract Background Random biological sequences are a topic of great interest in genome analysis since, according to a powerful paradigm, they represent the background noise from which the actual biological information must differentiate. Accordingly, the generation of random sequences has been investigated for a long time. Similarly, random object of a more complicated structure like RNA molecules or proteins are of interest. Results In this article, we present a new general framework for deriving algorithms for the non-uniform random generation of combinatorial objects according to the encoding and probability distribution implied by a stochastic context-free grammar. Briefly, the framework extends on the well-known recursive method for (uniform random generation and uses the popular framework of admissible specifications of combinatorial classes, introducing weighted combinatorial classes to allow for the non-uniform generation by means of unranking. This framework is used to derive an algorithm for the generation of RNA secondary structures of a given fixed size. We address the random generation of these structures according to a realistic distribution obtained from real-life data by using a very detailed context-free grammar (that models the class of RNA secondary structures by distinguishing between all known motifs in RNA structure. Compared to well-known sampling approaches used in several structure prediction tools (such as SFold ours has two major advantages: Firstly, after a preprocessing step in time O(n2 for the computation of all weighted class sizes needed, with our approach a set of m random secondary structures of a given structure size n can be computed in worst-case time complexity Om⋅n⋅ log(n while other algorithms typically have a runtime in O(m⋅n2. Secondly, our approach works with integer arithmetic only which is faster and saves us from all the discomforting details of using floating point arithmetic with

  9. A Quickly Tested Pascal Random Number Generator for Microcomputers.

    Science.gov (United States)

    1985-05-01

    in any way at equal intervals spaced h units apart, the serial correlation of the series can be obtained for various lags and tested against...pass handily. The unit range between zero and unity was divided into 100 equally spaced frequencies, and the generated random numbers were...NSDTEST; (*MEAN AND SDEV TESTS*) FREQKOLTEST; (*CHISQ FREQ DISTR AND KOLMOGOROFF -SMIRNOV TESTS*) PAIRTEST; (*TEST DISTR OF RANDOM PAIRS*) TRIOTEST; (*TEST

  10. Application of variational mode decomposition to seismic random noise reduction

    Science.gov (United States)

    Liu, Wei; Cao, Siyuan; Wang, Zhiming

    2017-08-01

    We have proposed a new denoising method for the simultaneous noise reduction and preservation of seismic signals based on variational mode decomposition (VMD). VMD is a recently developed adaptive signal decomposition method and an advance in non-stationary signal analysis. It solves the mode-mixing and non-optimal reconstruction performance problems of empirical mode decomposition that have existed for a long time. By using VMD, a multi-component signal can be non-recursively decomposed into a series of quasi-orthogonal intrinsic mode functions (IMFs), each of which has a relatively local frequency range. Meanwhile, the signal will focus on a smaller number of obtained IMFs after decomposition, and thus the denoised result is able to be obtained by reconstructing these signal-dominant IMFs. Synthetic examples are given to demonstrate the effectiveness of the proposed approach and comparison is made with the complete ensemble empirical mode decomposition, which demonstrates that the VMD algorithm has lower computational cost and better random noise elimination performance. The application of on field seismic data further illustrates the superior performance of our method in both random noise attenuation and the recovery of seismic events.

  11. Analysis of entropy extraction efficiencies in random number generation systems

    Science.gov (United States)

    Wang, Chao; Wang, Shuang; Chen, Wei; Yin, Zhen-Qiang; Han, Zheng-Fu

    2016-05-01

    Random numbers (RNs) have applications in many areas: lottery games, gambling, computer simulation, and, most importantly, cryptography [N. Gisin et al., Rev. Mod. Phys. 74 (2002) 145]. In cryptography theory, the theoretical security of the system calls for high quality RNs. Therefore, developing methods for producing unpredictable RNs with adequate speed is an attractive topic. Early on, despite the lack of theoretical support, pseudo RNs generated by algorithmic methods performed well and satisfied reasonable statistical requirements. However, as implemented, those pseudorandom sequences were completely determined by mathematical formulas and initial seeds, which cannot introduce extra entropy or information. In these cases, “random” bits are generated that are not at all random. Physical random number generators (RNGs), which, in contrast to algorithmic methods, are based on unpredictable physical random phenomena, have attracted considerable research interest. However, the way that we extract random bits from those physical entropy sources has a large influence on the efficiency and performance of the system. In this manuscript, we will review and discuss several randomness extraction schemes that are based on radiation or photon arrival times. We analyze the robustness, post-processing requirements and, in particular, the extraction efficiency of those methods to aid in the construction of efficient, compact and robust physical RNG systems.

  12. Quantum random flip-flop and its applications in random frequency synthesis and true random number generation

    Energy Technology Data Exchange (ETDEWEB)

    Stipčević, Mario, E-mail: mario.stipcevic@irb.hr [Photonics and Quantum Optics Research Unit, Center of Excellence for Advanced Materials and Sensing Devices, Ruđer Bošković Institute, Bijenička 54, 10000 Zagreb (Croatia)

    2016-03-15

    In this work, a new type of elementary logic circuit, named random flip-flop (RFF), is proposed, experimentally realized, and studied. Unlike conventional Boolean logic circuits whose action is deterministic and highly reproducible, the action of a RFF is intentionally made maximally unpredictable and, in the proposed realization, derived from a fundamentally random process of emission and detection of light quanta. We demonstrate novel applications of RFF in randomness preserving frequency division, random frequency synthesis, and random number generation. Possible usages of these applications in the information and communication technology, cryptographic hardware, and testing equipment are discussed.

  13. Solution-Processed Carbon Nanotube True Random Number Generator.

    Science.gov (United States)

    Gaviria Rojas, William A; McMorrow, Julian J; Geier, Michael L; Tang, Qianying; Kim, Chris H; Marks, Tobin J; Hersam, Mark C

    2017-08-09

    With the growing adoption of interconnected electronic devices in consumer and industrial applications, there is an increasing demand for robust security protocols when transmitting and receiving sensitive data. Toward this end, hardware true random number generators (TRNGs), commonly used to create encryption keys, offer significant advantages over software pseudorandom number generators. However, the vast network of devices and sensors envisioned for the "Internet of Things" will require small, low-cost, and mechanically flexible TRNGs with low computational complexity. These rigorous constraints position solution-processed semiconducting single-walled carbon nanotubes (SWCNTs) as leading candidates for next-generation security devices. Here, we demonstrate the first TRNG using static random access memory (SRAM) cells based on solution-processed SWCNTs that digitize thermal noise to generate random bits. This bit generation strategy can be readily implemented in hardware with minimal transistor and computational overhead, resulting in an output stream that passes standardized statistical tests for randomness. By using solution-processed semiconducting SWCNTs in a low-power, complementary architecture to achieve TRNG, we demonstrate a promising approach for improving the security of printable and flexible electronics.

  14. Fractal generator for efficient production of random planar patterns and symbols in digital mapping

    Science.gov (United States)

    Chen, Qiyu; Liu, Gang; Ma, Xiaogang; Li, Xinchuan; He, Zhenwen

    2017-08-01

    In digital cartography, the automatic generation of random planar patterns and symbols is still an ongoing challenge. Those patterns and symbols of randomness have randomly variated configurations and boundaries, and their generating algorithms are constrained by the shape features, cartographic standards and many other conditions. The fractal geometry offers favorable solutions to simulate random boundaries and patterns. In the work presented in this paper, we used both fractal theory and random Iterated Function Systems (IFS) to develop a method for the automatic generation of random planar patterns and symbols. The marshland and the trough cross-bedding patterns were used as two case studies for the implementation of the method. We first analyzed the morphological characteristics of those two planar patterns. Then we designed algorithms and implementation schemes addressing the features of each pattern. Finally, we ran the algorithms to generate the patterns and symbols, and compared them with the requirements of a few digital cartographic standards. The method presented in this paper has already been deployed in a digital mapping system for practical uses. The flexibility of the method also allows it to be reused and/or adapted in various software platforms for digital mapping.

  15. The Evolution of Random Number Generation in MUVES

    Science.gov (United States)

    2017-01-01

    3 2. Collins JC . Testing, selection, and implementation of random number genera- tors. Aberdeen Proving Ground (MD): Army Research Laboratory (US...261–269. 13, 16 5. L‘Ecuyer P. Tables of linear congruential generators of different sizes and good lattice structure. Mathematics of Computation

  16. Random Scenario Generation for a Multiple Target Tracking Environment Evaluation

    DEFF Research Database (Denmark)

    Hussain, Dil Muhammad Akbar

    2006-01-01

    The paper presents a simulation study on the generation of a random scenario for the performance of track splitting algorithm on a digital signal processor.  Much of the previous work [1] was done on specific (deterministic) scenarios. One of the reasons for considering the specific scenarios, wh...

  17. Simulations Using Random-Generated DNA and RNA Sequences

    Science.gov (United States)

    Bryce, C. F. A.

    1977-01-01

    Using a very simple computer program written in BASIC, a very large number of random-generated DNA or RNA sequences are obtained. Students use these sequences to predict complementary sequences and translational products, evaluate base compositions, determine frequencies of particular triplet codons, and suggest possible secondary structures.…

  18. REGAL: a library to randomly and exhaustively generate automata

    OpenAIRE

    Bassino, Frédérique; David, Julien; Nicaud, Cyril

    2007-01-01

    International audience; This paper presents a library devoted to the random and exhaustive generation of finite deterministic automata. This package provides a toolkit to experimentally study properties of automata, average complexities of algorithms dealing with automata or to compare different implementations of the same algorithm.

  19. Generation of genetically modified rodents using random ENU mutagenesis

    NARCIS (Netherlands)

    van Boxtel, R.; Cuppen, E.

    2011-01-01

    The generation of genetically modified animals using N-ethyl-N-nitrosourea (ENU) mutagenesis is a fast and highly effective method. The technique is based on treating male animals with the supermutagen ENU, which randomly introduces mutations in the spermatogonial stem cells. By breeding these

  20. Electrical generation of stationary light in random scattering media

    Science.gov (United States)

    Redmond, S. M.; Armstrong, G. L.; Chan, H.-Y.; Mattson, E.; Mock, A.; Li, B.; Potts, J. R.; Cui, M.; Rand, S. C.; Oliveira, S. L.; Marchal, J.; Hinklin, T.; Laine, R. M.

    2004-01-01

    In recent years there has been great interest in controlling the speed of propagation of electromagnetic waves. In gases and crystals, coherent techniques have been applied to alter the speed of light without changing the physical or chemical structure of the medium. Also, light transmitted by highly disordered solids has exhibited signatures of Anderson localization, indicating the existence of a regime of ``stopped'' light that is mediated by random elastic scattering. However, to date, light has not been generated in a random medium as a pointlike excitation that is fixed in space from the outset. Here we report experimental evidence for the electrical generation and confinement of light within nanosized volumes of a random dielectric scattering medium in which a population inversion has been established, and discuss the properties of these novel light sources.

  1. Source-Device-Independent Ultrafast Quantum Random Number Generation

    Science.gov (United States)

    Marangon, Davide G.; Vallone, Giuseppe; Villoresi, Paolo

    2017-02-01

    Secure random numbers are a fundamental element of many applications in science, statistics, cryptography and more in general in security protocols. We present a method that enables the generation of high-speed unpredictable random numbers from the quadratures of an electromagnetic field without any assumption on the input state. The method allows us to eliminate the numbers that can be predicted due to the presence of classical and quantum side information. In particular, we introduce a procedure to estimate a bound on the conditional min-entropy based on the entropic uncertainty principle for position and momentum observables of infinite dimensional quantum systems. By the above method, we experimentally demonstrated the generation of secure true random bits at a rate greater than 1.7 Gbit /s .

  2. Efficient biased random bit generation for parallel processing

    Energy Technology Data Exchange (ETDEWEB)

    Slone, Dale M. [Univ. of California, Davis, CA (United States)

    1994-09-28

    A lattice gas automaton was implemented on a massively parallel machine (the BBN TC2000) and a vector supercomputer (the CRAY C90). The automaton models Burgers equation ρt + ρρx = vρxx in 1 dimension. The lattice gas evolves by advecting and colliding pseudo-particles on a 1-dimensional, periodic grid. The specific rules for colliding particles are stochastic in nature and require the generation of many billions of random numbers to create the random bits necessary for the lattice gas. The goal of the thesis was to speed up the process of generating the random bits and thereby lessen the computational bottleneck of the automaton.

  3. Random number generation based on digital differential chaos

    KAUST Repository

    Zidan, Mohammed A.

    2012-07-29

    In this paper, we present a fully digital differential chaos based random number generator. The output of the digital circuit is proved to be chaotic by calculating the output time series maximum Lyapunov exponent. We introduce a new post processing technique to improve the distribution and statistical properties of the generated data. The post-processed output passes the NIST Sp. 800-22 statistical tests. The system is written in Verilog VHDL and realized on Xilinx Virtex® FPGA. The generator can fit into a very small area and have a maximum throughput of 2.1 Gb/s.

  4. DNA based random key generation and management for OTP encryption.

    Science.gov (United States)

    Zhang, Yunpeng; Liu, Xin; Sun, Manhui

    2017-09-01

    One-time pad (OTP) is a principle of key generation applied to the stream ciphering method which offers total privacy. The OTP encryption scheme has proved to be unbreakable in theory, but difficult to realize in practical applications. Because OTP encryption specially requires the absolute randomness of the key, its development has suffered from dense constraints. DNA cryptography is a new and promising technology in the field of information security. DNA chromosomes storing capabilities can be used as one-time pad structures with pseudo-random number generation and indexing in order to encrypt the plaintext messages. In this paper, we present a feasible solution to the OTP symmetric key generation and transmission problem with DNA at the molecular level. Through recombinant DNA technology, by using only sender-receiver known restriction enzymes to combine the secure key represented by DNA sequence and the T vector, we generate the DNA bio-hiding secure key and then place the recombinant plasmid in implanted bacteria for secure key transmission. The designed bio experiments and simulation results show that the security of the transmission of the key is further improved and the environmental requirements of key transmission are reduced. Analysis has demonstrated that the proposed DNA-based random key generation and management solutions are marked by high security and usability. Published by Elsevier B.V.

  5. GASPRNG: GPU accelerated scalable parallel random number generator library

    Science.gov (United States)

    Gao, Shuang; Peterson, Gregory D.

    2013-04-01

    Graphics processors represent a promising technology for accelerating computational science applications. Many computational science applications require fast and scalable random number generation with good statistical properties, so they use the Scalable Parallel Random Number Generators library (SPRNG). We present the GPU Accelerated SPRNG library (GASPRNG) to accelerate SPRNG in GPU-based high performance computing systems. GASPRNG includes code for a host CPU and CUDA code for execution on NVIDIA graphics processing units (GPUs) along with a programming interface to support various usage models for pseudorandom numbers and computational science applications executing on the CPU, GPU, or both. This paper describes the implementation approach used to produce high performance and also describes how to use the programming interface. The programming interface allows a user to be able to use GASPRNG the same way as SPRNG on traditional serial or parallel computers as well as to develop tightly coupled programs executing primarily on the GPU. We also describe how to install GASPRNG and use it. To help illustrate linking with GASPRNG, various demonstration codes are included for the different usage models. GASPRNG on a single GPU shows up to 280x speedup over SPRNG on a single CPU core and is able to scale for larger systems in the same manner as SPRNG. Because GASPRNG generates identical streams of pseudorandom numbers as SPRNG, users can be confident about the quality of GASPRNG for scalable computational science applications. Catalogue identifier: AEOI_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEOI_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: UTK license. No. of lines in distributed program, including test data, etc.: 167900 No. of bytes in distributed program, including test data, etc.: 1422058 Distribution format: tar.gz Programming language: C and CUDA. Computer: Any PC or

  6. Generation of correlated finite alphabet waveforms using gaussian random variables

    KAUST Repository

    Jardak, Seifallah

    2014-09-01

    Correlated waveforms have a number of applications in different fields, such as radar and communication. It is very easy to generate correlated waveforms using infinite alphabets, but for some of the applications, it is very challenging to use them in practice. Moreover, to generate infinite alphabet constant envelope correlated waveforms, the available research uses iterative algorithms, which are computationally very expensive. In this work, we propose simple novel methods to generate correlated waveforms using finite alphabet constant and non-constant-envelope symbols. To generate finite alphabet waveforms, the proposed method map the Gaussian random variables onto the phase-shift-keying, pulse-amplitude, and quadrature-amplitude modulation schemes. For such mapping, the probability-density-function of Gaussian random variables is divided into M regions, where M is the number of alphabets in the corresponding modulation scheme. By exploiting the mapping function, the relationship between the cross-correlation of Gaussian and finite alphabet symbols is derived. To generate equiprobable symbols, the area of each region is kept same. If the requirement is to have each symbol with its own unique probability, the proposed scheme allows us that as well. Although, the proposed scheme is general, the main focus of this paper is to generate finite alphabet waveforms for multiple-input multiple-output radar, where correlated waveforms are used to achieve desired beampatterns. © 2014 IEEE.

  7. New Design of Crypto-Based Pseudo random number generator (CBPRNG) using BLOW FISH cipher

    OpenAIRE

    T.Chalama Reddy; Dr.R.Seshadri

    2013-01-01

    Random Number Generators (RNGs) are an important building block for algorithms and protocols in cryptography. Random number generation is used in a wide variety of cryptographic operations, such as key generation and challenge/response protocols. A random number generator outputs a sequence of 0s and 1s such that at any position, the next bit cannot be expected on the previous bits. However, true random number produces non- deterministic output since if the same random generator is run twice,...

  8. PRIMITIVE MATRICES AND GENERATORS OF PSEUDO RANDOM SEQUENCES OF GALOIS

    Directory of Open Access Journals (Sweden)

    A. Beletsky

    2014-04-01

    Full Text Available In theory and practice of information cryptographic protection one of the key problems is the forming a binary pseudo-random sequences (PRS with a maximum length with acceptable statistical characteristics. PRS generators are usually implemented by linear shift register (LSR of maximum period with linear feedback [1]. In this paper we extend the concept of LSR, assuming that each of its rank (memory cell can be in one of the following condition. Let’s call such registers “generalized linear shift register.” The research goal is to develop algorithms for constructing Galois and Fibonacci generalized matrix of n-order over the field , which uniquely determined both the structure of corresponding generalized of n-order LSR maximal period, and formed on their basis Galois PRS generators of maximum length. Thus the article presents the questions of formation the primitive generalized Fibonacci and Galois arbitrary order matrix over the prime field . The synthesis of matrices is based on the use of irreducible polynomials of degree and primitive elements of the extended field generated by polynomial. The constructing methods of Galois and Fibonacci conjugated primitive matrices are suggested. The using possibilities of such matrices in solving the problem of constructing generalized generators of Galois pseudo-random sequences are discussed.

  9. At least some errors are randomly generated (Freud was wrong)

    Science.gov (United States)

    Sellen, A. J.; Senders, J. W.

    1986-01-01

    An experiment was carried out to expose something about human error generating mechanisms. In the context of the experiment, an error was made when a subject pressed the wrong key on a computer keyboard or pressed no key at all in the time allotted. These might be considered, respectively, errors of substitution and errors of omission. Each of seven subjects saw a sequence of three digital numbers, made an easily learned binary judgement about each, and was to press the appropriate one of two keys. Each session consisted of 1,000 presentations of randomly permuted, fixed numbers broken into 10 blocks of 100. One of two keys should have been pressed within one second of the onset of each stimulus. These data were subjected to statistical analyses in order to probe the nature of the error generating mechanisms. Goodness of fit tests for a Poisson distribution for the number of errors per 50 trial interval and for an exponential distribution of the length of the intervals between errors were carried out. There is evidence for an endogenous mechanism that may best be described as a random error generator. Furthermore, an item analysis of the number of errors produced per stimulus suggests the existence of a second mechanism operating on task driven factors producing exogenous errors. Some errors, at least, are the result of constant probability generating mechanisms with error rate idiosyncratically determined for each subject.

  10. Generating Correlated QPSK Waveforms By Exploiting Real Gaussian Random Variables

    KAUST Repository

    Jardak, Seifallah

    2012-11-01

    The design of waveforms with specified auto- and cross-correlation properties has a number of applications in multiple-input multiple-output (MIMO) radar, one of them is the desired transmit beampattern design. In this work, an algorithm is proposed to generate quadrature phase shift- keying (QPSK) waveforms with required cross-correlation properties using real Gaussian random-variables (RV’s). This work can be considered as the extension of what was presented in [1] to generate BPSK waveforms. This work will be extended for the generation of correlated higher-order phase shift-keying (PSK) and quadrature amplitude modulation (QAM) schemes that can better approximate the desired beampattern.

  11. Cellular Automata-Based Parallel Random Number Generators Using FPGAs

    Directory of Open Access Journals (Sweden)

    David H. K. Hoe

    2012-01-01

    Full Text Available Cellular computing represents a new paradigm for implementing high-speed massively parallel machines. Cellular automata (CA, which consist of an array of locally connected processing elements, are a basic form of a cellular-based architecture. The use of field programmable gate arrays (FPGAs for implementing CA accelerators has shown promising results. This paper investigates the design of CA-based pseudo-random number generators (PRNGs using an FPGA platform. To improve the quality of the random numbers that are generated, the basic CA structure is enhanced in two ways. First, the addition of a superrule to each CA cell is considered. The resulting self-programmable CA (SPCA uses the superrule to determine when to make a dynamic rule change in each CA cell. The superrule takes its inputs from neighboring cells and can be considered itself a second CA working in parallel with the main CA. When implemented on an FPGA, the use of lookup tables in each logic cell removes any restrictions on how the super-rules should be defined. Second, a hybrid configuration is formed by combining a CA with a linear feedback shift register (LFSR. This is advantageous for FPGA designs due to the compactness of the LFSR implementations. A standard software package for statistically evaluating the quality of random number sequences known as Diehard is used to validate the results. Both the SPCA and the hybrid CA/LFSR were found to pass all the Diehard tests.

  12. Random Sequence for Optimal Low-Power Laser Generated Ultrasound

    Science.gov (United States)

    Vangi, D.; Virga, A.; Gulino, M. S.

    2017-08-01

    Low-power laser generated ultrasounds are lately gaining importance in the research world, thanks to the possibility of investigating a mechanical component structural integrity through a non-contact and Non-Destructive Testing (NDT) procedure. The ultrasounds are, however, very low in amplitude, making it necessary to use pre-processing and post-processing operations on the signals to detect them. The cross-correlation technique is used in this work, meaning that a random signal must be used as laser input. For this purpose, a highly random and simple-to-create code called T sequence, capable of enhancing the ultrasound detectability, is introduced (not previously available at the state of the art). Several important parameters which characterize the T sequence can influence the process: the number of pulses Npulses , the pulse duration δ and the distance between pulses dpulses . A Finite Element FE model of a 3 mm steel disk has been initially developed to analytically study the longitudinal ultrasound generation mechanism and the obtainable outputs. Later, experimental tests have shown that the T sequence is highly flexible for ultrasound detection purposes, making it optimal to use high Npulses and δ but low dpulses . In the end, apart from describing all phenomena that arise in the low-power laser generation process, the results of this study are also important for setting up an effective NDT procedure using this technology.

  13. Random phase-free computer-generated hologram

    CERN Document Server

    Shimobaba, Tomoyoshi

    2015-01-01

    Addition of random phase to the object light is required in computer-generated holograms (CGHs) to widely diffuse the object light and to avoid its concentration on the CGH; however, this addition causes considerable speckle noise in the reconstructed image. For improving the speckle noise problem, techniques such as iterative phase retrieval algorithms and multi-random phase method are used; however, they are time consuming and are of limited effectiveness. Herein, we present a simple and computationally inexpensive method that drastically improves the image quality and reduces the speckle noise by multiplying the object light with the virtual convergence light. Feasibility of the proposed method is shown using simulations and optical reconstructions; moreover, we apply it to lens-less zoom-able holographic projection. The proposed method is useful for the speckle problems in holographic applications.

  14. Soliton generation from randomly modulated return-to-zero pulses

    Science.gov (United States)

    Derevyanko, Stanislav A.; Prilepsky, Jaroslaw E.

    2008-11-01

    We consider return-to-zero (RZ) pulses with random phase modulation propagating in a nonlinear channel (modelled by the integrable nonlinear Schrödinger equation, NLSE). We suggest two different models for the phase fluctuations of the optical field: (i) Gaussian short-correlated fluctuations and (ii) generalized telegraph process. Using the rectangular-shaped pulse form we demonstrate that the presence of phase fluctuations of both types strongly influences the number of solitons generated in the channel. It is also shown that increasing the correlation time for the random phase fluctuations affects the coherent content of a pulse in a non-trivial way. The result obtained has potential consequences for all-optical processing and design of optical decision elements.

  15. Generation of correlated finite alphabet waveforms using gaussian random variables

    KAUST Repository

    Ahmed, Sajid

    2016-01-13

    Various examples of methods and systems are provided for generation of correlated finite alphabet waveforms using Gaussian random variables in, e.g., radar and communication applications. In one example, a method includes mapping an input signal comprising Gaussian random variables (RVs) onto finite-alphabet non-constant-envelope (FANCE) symbols using a predetermined mapping function, and transmitting FANCE waveforms through a uniform linear array of antenna elements to obtain a corresponding beampattern. The FANCE waveforms can be based upon the mapping of the Gaussian RVs onto the FANCE symbols. In another example, a system includes a memory unit that can store a plurality of digital bit streams corresponding to FANCE symbols and a front end unit that can transmit FANCE waveforms through a uniform linear array of antenna elements to obtain a corresponding beampattern. The system can include a processing unit that can encode the input signal and/or determine the mapping function.

  16. Comparison of a quantum random number generator with pseudorandom number generators for their use in molecular Monte Carlo simulations.

    Science.gov (United States)

    Ghersi, Dario; Parakh, Abhishek; Mezei, Mihaly

    2017-12-05

    Four pseudorandom number generators were compared with a physical, quantum-based random number generator using the NIST suite of statistical tests, which only the quantum-based random number generator could successfully pass. We then measured the effect of the five random number generators on various calculated properties in different Markov-chain Monte Carlo simulations. Two types of systems were tested: conformational sampling of a small molecule in aqueous solution and liquid methanol under constant temperature and pressure. The results show that poor quality pseudorandom number generators produce results that deviate significantly from those obtained with the quantum-based random number generator, particularly in the case of the small molecule in aqueous solution setup. In contrast, the widely used Mersenne Twister pseudorandom generator and a 64-bit Linear Congruential Generator with a scrambler produce results that are statistically indistinguishable from those obtained with the quantum-based random number generator. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  17. Quantum Statistical Testing of a Quantum Random Number Generator

    Energy Technology Data Exchange (ETDEWEB)

    Humble, Travis S [ORNL

    2014-01-01

    The unobservable elements in a quantum technology, e.g., the quantum state, complicate system verification against promised behavior. Using model-based system engineering, we present methods for verifying the opera- tion of a prototypical quantum random number generator. We begin with the algorithmic design of the QRNG followed by the synthesis of its physical design requirements. We next discuss how quantum statistical testing can be used to verify device behavior as well as detect device bias. We conclude by highlighting how system design and verification methods must influence effort to certify future quantum technologies.

  18. Fully Digital Chaotic Oscillators Applied to Pseudo Random Number Generation

    KAUST Repository

    Mansingka, Abhinav S.

    2012-05-01

    adapted for pseudo random number generation by truncating statistically defective bits. Finally, a novel post-processing technique using the Fibonacci series is proposed and implemented with a non-autonomous driven hyperchaotic system to provide pseudo random number generators with high nonlinear complexity and controllable period length that enables full utilization of all branches of the chaotic output as statistically secure pseudo random output.

  19. High-Quality Random Number Generation Software for High-Performance Computing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Random number (RN) generation is the key software component that permits random sampling. Software for parallel RN generation (RNG) should be based on RNGs that are...

  20. Implications of random variation in the Stand Prognosis Model

    Science.gov (United States)

    David A. Hamilton

    1991-01-01

    Although the Stand Prognosis Model has several stochastic components, features have been included in the model in an attempt to minimize run-to-run variation attributable to these stochastic components. This has led many users to assume that comparisons of management alternatives could be made based on a single run of the model for each alternative. Recent analyses...

  1. Variational Hidden Conditional Random Fields with Coupled Dirichlet Process Mixtures

    NARCIS (Netherlands)

    Bousmalis, K.; Zafeiriou, S.; Morency, L.P.; Pantic, Maja; Ghahramani, Z.

    Hidden Conditional Random Fields (HCRFs) are discriminative latent variable models which have been shown to successfully learn the hidden structure of a given classification problem. An infinite HCRF is an HCRF with a countably infinite number of hidden states, which rids us not only of the

  2. Analysis of a non-diffractive beam generated from an annular beam in random media

    Science.gov (United States)

    Peng, Ziqi; Shiina, Tatsuo

    2017-11-01

    An annular beam has the ability to self-transform into a non-diffractive beam when it propagates in air at a long distance. In our previous study, we propagated an annular beam in random media and obtained a non-diffractive beam at a short propagation distance of a few tens centimeters by adjusting the concentration of random media and narrowing the view angle of the receiver. In this paper, we aim to analyze the components and characteristics of a non-diffractive beam and elucidate how the non-diffractive beam is generated in random media. The intensity variation of the scattered waveform is examined when the distance between the receiver and the back plane of a medium tank is changed. The waveform scattered in random media is constructed from forward scattering light at the center and multiple scattering light in the surrounding part. The forward scattering light at the center generates the non-diffractive beam. In numerical analysis based on diffusion theory, the calculation result of the non-diffractive beam shows agreement with the experimental result.

  3. Policies Affect Preferences: Evidence from Random Variation in Abortion Jurisprudence

    OpenAIRE

    Chen, Daniel L.; Levonyan, Vardges; Yeh, Susan

    2016-01-01

    Whether policies shift preferences is relevant to policy design. We exploit the random assignment of U.S. federal judges creating geographically local precedent and the fact that judges’ politics, religion, and race predict decision-making in abortion jurisprudence. Instrumenting for abortion jurisprudence with exogenous judicial characteristics, we estimate the impact of abortion jurisprudence on state laws, campaign donations, and abortion attitudes. We verify information transmission in th...

  4. Generation of Random Wind Speed Profiles for Evaluation of Stress in WT Power Converters

    DEFF Research Database (Denmark)

    Pigazo, Alberto; Qin, Zian; Liserre, Marco

    2013-01-01

    Wind turbines are subjected to wind speed variations that cause a power profile that will stress the overall system. This stress is tranfered to the power converter, resulting in temperature variations of the power devices and, hence, causing the reduction of the lifetime. The lifetime expectation...... changes depending on the real wind speed once the wind turbine is operating. Usually, the real wind speed profiles are employed to evaluate this stress but they do not consider all possible operation conditions and require intensive computations. To solve these issues, this paper proposes the generation...... of random wind speed profiles, based on the measured ones, in order to evaluate the thermal stress of the power devices based on a simplified statistical approach....

  5. Generative Learning Objects Instantiated with Random Numbers Based Expressions

    Directory of Open Access Journals (Sweden)

    Ciprian Bogdan Chirila

    2015-12-01

    Full Text Available The development of interactive e-learning content requires special skills like programming techniques, web integration, graphic design etc. Generally, online educators do not possess such skills and their e-learning products tend to be static like presentation slides and textbooks. In this paper we propose a new interactive model of generative learning objects as a compromise betweenstatic, dull materials and dynamic, complex software e-learning materials developed by specialized teams. We find that random numbers based automatic initialization learning objects increases content diversity, interactivity thus enabling learners’ engagement. The resulted learning object model is at a limited level of complexity related to special e-learning software, intuitive and capable of increasing learners’ interactivity, engagement and motivation through dynamic content. The approach was applied successfully on several computer programing disciplines.

  6. Random phenotypic variation of yeast (Saccharomyces cerevisiae) single-gene knockouts fits a double pareto-lognormal distribution.

    Science.gov (United States)

    Graham, John H; Robb, Daniel T; Poe, Amy R

    2012-01-01

    Distributed robustness is thought to influence the buffering of random phenotypic variation through the scale-free topology of gene regulatory, metabolic, and protein-protein interaction networks. If this hypothesis is true, then the phenotypic response to the perturbation of particular nodes in such a network should be proportional to the number of links those nodes make with neighboring nodes. This suggests a probability distribution approximating an inverse power-law of random phenotypic variation. Zero phenotypic variation, however, is impossible, because random molecular and cellular processes are essential to normal development. Consequently, a more realistic distribution should have a y-intercept close to zero in the lower tail, a mode greater than zero, and a long (fat) upper tail. The double Pareto-lognormal (DPLN) distribution is an ideal candidate distribution. It consists of a mixture of a lognormal body and upper and lower power-law tails. If our assumptions are true, the DPLN distribution should provide a better fit to random phenotypic variation in a large series of single-gene knockout lines than other skewed or symmetrical distributions. We fit a large published data set of single-gene knockout lines in Saccharomyces cerevisiae to seven different probability distributions: DPLN, right Pareto-lognormal (RPLN), left Pareto-lognormal (LPLN), normal, lognormal, exponential, and Pareto. The best model was judged by the Akaike Information Criterion (AIC). Phenotypic variation among gene knockouts in S. cerevisiae fits a double Pareto-lognormal (DPLN) distribution better than any of the alternative distributions, including the right Pareto-lognormal and lognormal distributions. A DPLN distribution is consistent with the hypothesis that developmental stability is mediated, in part, by distributed robustness, the resilience of gene regulatory, metabolic, and protein-protein interaction networks. Alternatively, multiplicative cell growth, and the mixing of

  7. Multi-bit quantum random number generation by measuring positions of arrival photons.

    Science.gov (United States)

    Yan, Qiurong; Zhao, Baosheng; Liao, Qinghong; Zhou, Nanrun

    2014-10-01

    We report upon the realization of a novel multi-bit optical quantum random number generator by continuously measuring the arrival positions of photon emitted from a LED using MCP-based WSA photon counting imaging detector. A spatial encoding method is proposed to extract multi-bits random number from the position coordinates of each detected photon. The randomness of bits sequence relies on the intrinsic randomness of the quantum physical processes of photonic emission and subsequent photoelectric conversion. A prototype has been built and the random bit generation rate could reach 8 Mbit/s, with random bit generation efficiency of 16 bits per detected photon. FPGA implementation of Huffman coding is proposed to reduce the bias of raw extracted random bits. The random numbers passed all tests for physical random number generator.

  8. Generation and Analysis of Constrained Random Sampling Patterns

    DEFF Research Database (Denmark)

    Pierzchlewski, Jacek; Arildsen, Thomas

    2016-01-01

    Random sampling is a technique for signal acquisition which is gaining popularity in practical signal processing systems. Nowadays, event-driven analog-to-digital converters make random sampling feasible in practical applications. A process of random sampling is defined by a sampling pattern, whi...

  9. Realization of a Quantum Random Generator Certified with the Kochen-Specker Theorem.

    Science.gov (United States)

    Kulikov, Anatoly; Jerger, Markus; Potočnik, Anton; Wallraff, Andreas; Fedorov, Arkady

    2017-12-15

    Random numbers are required for a variety of applications from secure communications to Monte Carlo simulation. Yet randomness is an asymptotic property, and no output string generated by a physical device can be strictly proven to be random. We report an experimental realization of a quantum random number generator (QRNG) with randomness certified by quantum contextuality and the Kochen-Specker theorem. The certification is not performed in a device-independent way but through a rigorous theoretical proof of each outcome being value indefinite even in the presence of experimental imperfections. The analysis of the generated data confirms the incomputable nature of our QRNG.

  10. Realization of a Quantum Random Generator Certified with the Kochen-Specker Theorem

    Science.gov (United States)

    Kulikov, Anatoly; Jerger, Markus; Potočnik, Anton; Wallraff, Andreas; Fedorov, Arkady

    2017-12-01

    Random numbers are required for a variety of applications from secure communications to Monte Carlo simulation. Yet randomness is an asymptotic property, and no output string generated by a physical device can be strictly proven to be random. We report an experimental realization of a quantum random number generator (QRNG) with randomness certified by quantum contextuality and the Kochen-Specker theorem. The certification is not performed in a device-independent way but through a rigorous theoretical proof of each outcome being value indefinite even in the presence of experimental imperfections. The analysis of the generated data confirms the incomputable nature of our QRNG.

  11. LOMA: A fast method to generate efficient tagged-random primers despite amplification bias of random PCR on pathogens

    Directory of Open Access Journals (Sweden)

    Lee Wah

    2008-09-01

    Full Text Available Abstract Background Pathogen detection using DNA microarrays has the potential to become a fast and comprehensive diagnostics tool. However, since pathogen detection chips currently utilize random primers rather than specific primers for the RT-PCR step, bias inherent in random PCR amplification becomes a serious problem that causes large inaccuracies in hybridization signals. Results In this paper, we study how the efficiency of random PCR amplification affects hybridization signals. We describe a model that predicts the amplification efficiency of a given random primer on a target viral genome. The prediction allows us to filter false-negative probes of the genome that lie in regions of poor random PCR amplification and improves the accuracy of pathogen detection. Subsequently, we propose LOMA, an algorithm to generate random primers that have good amplification efficiency. Wet-lab validation showed that the generated random primers improve the amplification efficiency significantly. Conclusion The blind use of a random primer with attached universal tag (random-tagged primer in a PCR reaction on a pathogen sample may not lead to a successful amplification. Thus, the design of random-tagged primers is an important consideration when performing PCR.

  12. A practical guide and power analysis for GLMMs: detecting among treatment variation in random effects.

    Science.gov (United States)

    Kain, Morgan P; Bolker, Ben M; McCoy, Michael W

    2015-01-01

    In ecology and evolution generalized linear mixed models (GLMMs) are becoming increasingly used to test for differences in variation by treatment at multiple hierarchical levels. Yet, the specific sampling schemes that optimize the power of an experiment to detect differences in random effects by treatment/group remain unknown. In this paper we develop a blueprint for conducting power analyses for GLMMs focusing on detecting differences in variance by treatment. We present parameterization and power analyses for random-intercepts and random-slopes GLMMs because of their generality as focal parameters for most applications and because of their immediate applicability to emerging questions in the field of behavioral ecology. We focus on the extreme case of hierarchically structured binomial data, though the framework presented here generalizes easily to any error distribution model. First, we determine the optimal ratio of individuals to repeated measures within individuals that maximizes power to detect differences by treatment in among-individual variation in intercept, among-individual variation in slope, and within-individual variation in intercept. Second, we explore how power to detect differences in target variance parameters is affected by total variation. Our results indicate heterogeneity in power across ratios of individuals to repeated measures with an optimal ratio determined by both the target variance parameter and total sample size. Additionally, power to detect each variance parameter was low overall (in most cases >1,000 total observations per treatment needed to achieve 80% power) and decreased with increasing variance in non-target random effects. With growing interest in variance as the parameter of inquiry, these power analyses provide a crucial component for designing experiments focused on detecting differences in variance. We hope to inspire novel experimental designs in ecology and evolution investigating the causes and implications of

  13. Algorithm for generation pseudo-random series with arbitrarily assigned distribution law

    Directory of Open Access Journals (Sweden)

    В.С. Єременко

    2005-04-01

    Full Text Available  Method for generation pseudo-random series with arbitrarily assigned distribution law has been proposed. The praxis of using proposed method for generation pseudo-random series with anti-modal and approximate to Gaussian distribution law has been investigated.

  14. Generating Variable and Random Schedules of Reinforcement Using Microsoft Excel Macros

    Science.gov (United States)

    Bancroft, Stacie L; Bourret, Jason C

    2008-01-01

    Variable reinforcement schedules are used to arrange the availability of reinforcement following varying response ratios or intervals of time. Random reinforcement schedules are subtypes of variable reinforcement schedules that can be used to arrange the availability of reinforcement at a constant probability across number of responses or time. Generating schedule values for variable and random reinforcement schedules can be difficult. The present article describes the steps necessary to write macros in Microsoft Excel that will generate variable-ratio, variable-interval, variable-time, random-ratio, random-interval, and random-time reinforcement schedule values. PMID:18595286

  15. High-speed quantum-random number generation by continuous measurement of arrival time of photons.

    Science.gov (United States)

    Yan, Qiurong; Zhao, Baosheng; Hua, Zhang; Liao, Qinghong; Yang, Hao

    2015-07-01

    We demonstrate a novel high speed and multi-bit optical quantum random number generator by continuously measuring arrival time of photons with a common starting point. To obtain the unbiased and post-processing free random bits, the measured photon arrival time is converted into the sum of integral multiple of a fixed period and a phase time. Theoretical and experimental results show that the phase time is an independent and uniform random variable. A random bit extraction method by encoding the phase time is proposed. An experimental setup has been built and the unbiased random bit generation rate could reach 128 Mb/s, with random bit generation efficiency of 8 bits per detected photon. The random numbers passed all tests in the statistical test suite.

  16. Variational perturbation and extended Plefka approaches to dynamics on random networks: the case of the kinetic Ising model

    Science.gov (United States)

    Bachschmid-Romano, L.; Battistin, C.; Opper, M.; Roudi, Y.

    2016-10-01

    We describe and analyze some novel approaches for studying the dynamics of Ising spin glass models. We first briefly consider the variational approach based on minimizing the Kullback-Leibler divergence between independent trajectories and the real ones and note that this approach only coincides with the mean field equations from the saddle point approximation to the generating functional when the dynamics is defined through a logistic link function, which is the case for the kinetic Ising model with parallel update. We then spend the rest of the paper developing two ways of going beyond the saddle point approximation to the generating functional. In the first one, we develop a variational perturbative approximation to the generating functional by expanding the action around a quadratic function of the local fields and conjugate local fields whose parameters are optimized. We derive analytical expressions for the optimal parameters and show that when the optimization is suitably restricted, we recover the mean field equations that are exact for the fully asymmetric random couplings (Mézard and Sakellariou 2011 J. Stat. Mech. 2011 L07001). However, without this restriction the results are different. We also describe an extended Plefka expansion in which in addition to the magnetization, we also fix the correlation and response functions. Finally, we numerically study the performance of these approximations for Sherrington-Kirkpatrick type couplings for various coupling strengths and the degrees of coupling symmetry, for both temporally constant but random, as well as time varying external fields. We show that the dynamical equations derived from the extended Plefka expansion outperform the others in all regimes, although it is computationally more demanding. The unconstrained variational approach does not perform well in the small coupling regime, while it approaches dynamical TAP equations of (Roudi and Hertz 2011 J. Stat. Mech. 2011 P03031) for strong couplings.

  17. Variation in commercial smoking mixtures containing third-generation synthetic cannabinoids.

    Science.gov (United States)

    Frinculescu, Anca; Lyall, Catherine L; Ramsey, John; Miserez, Bram

    2017-02-01

    Variation in ingredients (qualitative variation) and in quantity of active compounds (quantitative variation) in herbal smoking mixtures containing synthetic cannabinoids has been shown for older products. This can be dangerous to the user, as accurate and reproducible dosing is impossible. In this study, 69 packages containing third-generation cannabinoids of seven brands on the UK market in 2014 were analyzed both qualitatively and quantitatively for variation. When comparing the labels to actual active ingredients identified in the sample, only one brand was shown to be correctly labelled. The other six brands contained less, more, or ingredients other than those listed on the label. Only two brands were inconsistent, containing different active ingredients in different samples. Quantitative variation was assessed both within one package and between several packages. Within-package variation was within a 10% range for five of the seven brands, but two brands showed larger variation, up to 25% (Relative Standard Deviation). Variation between packages was significantly higher, with variation up to 38% and maximum concentration up to 2.7 times higher than the minimum concentration. Both qualitative and quantitative variation are common in smoking mixtures and endanger the user, as it is impossible to estimate the dose or to know the compound consumed when smoking commercial mixtures. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  18. Surface texture generation during cylindrical milling in the aspect of cutting force variations

    Science.gov (United States)

    Wojciechowski, S.; Twardowski, P.; Pelic, M.

    2014-03-01

    The work presented here concentrates on surface texture analysis, after cylindrical milling of hardened steel. Cutting force variations occurring in the machining process have direct influence on the cutter displacements and thus on the generated surface texture. Therefore, in these experiments, the influence of active number of teeth (zc) on the cutting force variations was investigated. Cutting forces and cutter displacements were measured during machining process (online) using, namely piezoelectric force dynamometer and 3D laser vibrometer. Surface roughness parameters were measured using stylus surface profiler. The surface roughness model including cutting parameters (fz, D) and cutting force variations was also developed. The research revealed that in cylindrical milling process, cutting force variations have immediate influence on surface texture generation.

  19. Precise colocalization of interacting structural and pigmentary elements generates extensive color pattern variation in Phelsuma lizards.

    OpenAIRE

    Saenko Suzanne V; Teyssier Jérémie; van der Marel Dirk; Milinkovitch Michel C

    2013-01-01

    Background Color traits in animals play crucial roles in thermoregulation, photoprotection, camouflage, and visual communication, and are amenable to objective quantification and modeling. However, the extensive variation in non-melanic pigments and structural colors in squamate reptiles has been largely disregarded. Here, we used an integrated approach to investigate the morphological basis and physical mechanisms generating variation in color traits in tropical day geckos of the genus Phels...

  20. Generation and monitoring of a discrete stable random process

    CERN Document Server

    Hopcraft, K I; Matthews, J O

    2002-01-01

    A discrete stochastic process with stationary power law distribution is obtained from a death-multiple immigration population model. Emigrations from the population form a random series of events which are monitored by a counting process with finite-dynamic range and response time. It is shown that the power law behaviour of the population is manifested in the intermittent behaviour of the series of events. (letter to the editor)

  1. A modern theory of random variation with applications in stochastic calculus, financial mathematics, and Feynman integration

    CERN Document Server

    Muldowney, Patrick

    2012-01-01

    A Modern Theory of Random Variation is a new and radical re-formulation of the mathematical underpinnings of subjects as diverse as investment, communication engineering, and quantum mechanics. Setting aside the classical theory of probability measure spaces, the book utilizes a mathematically rigorous version of the theory of random variation that bases itself exclusively on finitely additive probability distribution functions. In place of twentieth century Lebesgue integration and measure theory, the author uses the simpler concept of Riemann sums, and the non-absolute Riemann-type integration of Henstock. Readers are supplied with an accessible approach to standard elements of probability theory such as the central limmit theorem and Brownian motion as well as remarkable, new results on Feynman diagrams and stochastic integrals. Throughout the book, detailed numerical demonstrations accompany the discussions of abstract mathematical theory, from the simplest elements of the subject to the most complex. I...

  2. Changes in quality of life from a homelessness intervention: true change, response shift, or random variation.

    Science.gov (United States)

    Powell, Guido Antonio; Adair, Carol E; Streiner, David L; Mayo, Nancy; Latimer, Eric

    2017-07-01

    Participants experiencing homelessness and mental illness who received housing and support through the At Home/Chez Soi trial showed modest gains in quality of life (QOL) compared to treatment as usual participants. Participants' QOL ratings over time may have been affected by either response shift triggered by new life circumstances or by random variation in the meaning of QOL ratings. This study seeks to identify both phenomena to estimate the intervention's effect on true change in QOL. Using the residuals from a regression model of the global item of Lehman's 20-item quality of life interview (QOLI-20), latent trajectory analysis was used to identify response shift, while a measure of overall variability in residuals identified random variation of QOL. The latter was used to adjust group comparisons of QOLI-20 total scores and the global item. Equivalent distributions of both groups' participants across latent trajectory classes (χ 2  = 2.97, p = .397) suggest that the intervention did not trigger response shift. However, random variation interacted significantly with the treatment effect on global item ratings. For every increase of one standard deviation of residuals, treatment odds ratios decreased by a factor of 0.70 (SE 1.18, p = .036, 95% CI 0.50-0.98). Measuring random variation in QOL ratings from the standard deviation of residuals offers the ability to approximate, although indirectly, how participants' QOL is truly affected by a housing intervention. Specifically, we found that QOL improvement is more evident when QOL ratings have a consistent meaning over time.

  3. Recommendations and illustrations for the evaluation of photonic random number generators

    Science.gov (United States)

    Hart, Joseph D.; Terashima, Yuta; Uchida, Atsushi; Baumgartner, Gerald B.; Murphy, Thomas E.; Roy, Rajarshi

    2017-09-01

    The never-ending quest to improve the security of digital information combined with recent improvements in hardware technology has caused the field of random number generation to undergo a fundamental shift from relying solely on pseudo-random algorithms to employing optical entropy sources. Despite these significant advances on the hardware side, commonly used statistical measures and evaluation practices remain ill-suited to understand or quantify the optical entropy that underlies physical random number generation. We review the state of the art in the evaluation of optical random number generation and recommend a new paradigm: quantifying entropy generation and understanding the physical limits of the optical sources of randomness. In order to do this, we advocate for the separation of the physical entropy source from deterministic post-processing in the evaluation of random number generators and for the explicit consideration of the impact of the measurement and digitization process on the rate of entropy production. We present the Cohen-Procaccia estimate of the entropy rate h (𝜖 ,τ ) as one way to do this. In order to provide an illustration of our recommendations, we apply the Cohen-Procaccia estimate as well as the entropy estimates from the new NIST draft standards for physical random number generators to evaluate and compare three common optical entropy sources: single photon time-of-arrival detection, chaotic lasers, and amplified spontaneous emission.

  4. On random field Completely Automated Public Turing Test to Tell Computers and Humans Apart generation.

    Science.gov (United States)

    Kouritzin, Michael A; Newton, Fraser; Wu, Biao

    2013-04-01

    Herein, we propose generating CAPTCHAs through random field simulation and give a novel, effective and efficient algorithm to do so. Indeed, we demonstrate that sufficient information about word tests for easy human recognition is contained in the site marginal probabilities and the site-to-nearby-site covariances and that these quantities can be embedded directly into certain conditional probabilities, designed for effective simulation. The CAPTCHAs are then partial random realizations of the random CAPTCHA word. We start with an initial random field (e.g., randomly scattered letter pieces) and use Gibbs resampling to re-simulate portions of the field repeatedly using these conditional probabilities until the word becomes human-readable. The residual randomness from the initial random field together with the random implementation of the CAPTCHA word provide significant resistance to attack. This results in a CAPTCHA, which is unrecognizable to modern optical character recognition but is recognized about 95% of the time in a human readability study.

  5. Lightweight PUF-based Key and Random Number Generation

    OpenAIRE

    Van Herrewege, Anthony

    2015-01-01

    As embedded electronics continue to be integrated into our daily lives at such a pace that there are nowadays more cellphones than people on the planet, security is becoming ever more crucial. Unfortunately, this is all too often realized as an afterthought and thus the security implementations in many embedded devices offer little to no practical protection. Security does not require only cryptographic algorithms; two other critical modules in a secure system are a key generation module and ...

  6. Copy number variation of individual cattle genomes using next-generation sequencing

    Science.gov (United States)

    Copy number variations (CNVs) affect a wide range of phenotypic traits; however, CNVs in or near segmental duplication regions are often intractable. Using a read depth approach based on next-generation sequencing, we examined genome-wide copy number differences among five taurine (three Angus, one ...

  7. Identification of Nucleotide Variation in Genomes Using Next-Generation Sequencing

    NARCIS (Netherlands)

    Megens, H.J.W.C.; Groenen, M.A.M.

    2012-01-01

    Discovery of genome-wide variation has taken a huge leap forward with the introduction of next-generation sequencing (NGS) technology. Variant discovery requires sampling of a number of haplotypes. This can be either the two haplotypes of a diploid organism or multiple haplotypes in a population.

  8. A Comparison of Three Random Number Generators for Aircraft Dynamic Modeling Applications

    Science.gov (United States)

    Grauer, Jared A.

    2017-01-01

    Three random number generators, which produce Gaussian white noise sequences, were compared to assess their suitability in aircraft dynamic modeling applications. The first generator considered was the MATLAB (registered) implementation of the Mersenne-Twister algorithm. The second generator was a website called Random.org, which processes atmospheric noise measured using radios to create the random numbers. The third generator was based on synthesis of the Fourier series, where the random number sequences are constructed from prescribed amplitude and phase spectra. A total of 200 sequences, each having 601 random numbers, for each generator were collected and analyzed in terms of the mean, variance, normality, autocorrelation, and power spectral density. These sequences were then applied to two problems in aircraft dynamic modeling, namely estimating stability and control derivatives from simulated onboard sensor data, and simulating flight in atmospheric turbulence. In general, each random number generator had good performance and is well-suited for aircraft dynamic modeling applications. Specific strengths and weaknesses of each generator are discussed. For Monte Carlo simulation, the Fourier synthesis method is recommended because it most accurately and consistently approximated Gaussian white noise and can be implemented with reasonable computational effort.

  9. Doing Better by Getting Worse: Posthypnotic Amnesia Improves Random Number Generation

    Science.gov (United States)

    Terhune, Devin Blair; Brugger, Peter

    2011-01-01

    Although forgetting is often regarded as a deficit that we need to control to optimize cognitive functioning, it can have beneficial effects in a number of contexts. We examined whether disrupting memory for previous numerical responses would attenuate repetition avoidance (the tendency to avoid repeating the same number) during random number generation and thereby improve the randomness of responses. Low suggestible and low dissociative and high dissociative highly suggestible individuals completed a random number generation task in a control condition, following a posthypnotic amnesia suggestion to forget previous numerical responses, and in a second control condition following the cancellation of the suggestion. High dissociative highly suggestible participants displayed a selective increase in repetitions during posthypnotic amnesia, with equivalent repetition frequency to a random system, whereas the other two groups exhibited repetition avoidance across conditions. Our results demonstrate that temporarily disrupting memory for previous numerical responses improves random number generation. PMID:22195022

  10. Doing better by getting worse: posthypnotic amnesia improves random number generation.

    Directory of Open Access Journals (Sweden)

    Devin Blair Terhune

    Full Text Available Although forgetting is often regarded as a deficit that we need to control to optimize cognitive functioning, it can have beneficial effects in a number of contexts. We examined whether disrupting memory for previous numerical responses would attenuate repetition avoidance (the tendency to avoid repeating the same number during random number generation and thereby improve the randomness of responses. Low suggestible and low dissociative and high dissociative highly suggestible individuals completed a random number generation task in a control condition, following a posthypnotic amnesia suggestion to forget previous numerical responses, and in a second control condition following the cancellation of the suggestion. High dissociative highly suggestible participants displayed a selective increase in repetitions during posthypnotic amnesia, with equivalent repetition frequency to a random system, whereas the other two groups exhibited repetition avoidance across conditions. Our results demonstrate that temporarily disrupting memory for previous numerical responses improves random number generation.

  11. Precise colocalization of interacting structural and pigmentary elements generates extensive color pattern variation in Phelsuma lizards.

    Science.gov (United States)

    Saenko, Suzanne V; Teyssier, Jérémie; van der Marel, Dirk; Milinkovitch, Michel C

    2013-10-07

    Color traits in animals play crucial roles in thermoregulation, photoprotection, camouflage, and visual communication, and are amenable to objective quantification and modeling. However, the extensive variation in non-melanic pigments and structural colors in squamate reptiles has been largely disregarded. Here, we used an integrated approach to investigate the morphological basis and physical mechanisms generating variation in color traits in tropical day geckos of the genus Phelsuma. Combining histology, optics, mass spectrometry, and UV and Raman spectroscopy, we found that the extensive variation in color patterns within and among Phelsuma species is generated by complex interactions between, on the one hand, chromatophores containing yellow/red pteridine pigments and, on the other hand, iridophores producing structural color by constructive interference of light with guanine nanocrystals. More specifically, we show that 1) the hue of the vivid dorsolateral skin is modulated both by variation in geometry of structural, highly ordered narrowband reflectors, and by the presence of yellow pigments, and 2) that the reflectivity of the white belly and of dorsolateral pigmentary red marks, is increased by underlying structural disorganized broadband reflectors. Most importantly, these interactions require precise colocalization of yellow and red chromatophores with different types of iridophores, characterized by ordered and disordered nanocrystals, respectively. We validated these results through numerical simulations combining pigmentary components with a multilayer interferential optical model. Finally, we show that melanophores form dark lateral patterns but do not significantly contribute to variation in blue/green or red coloration, and that changes in the pH or redox state of pigments provide yet another source of color variation in squamates. Precisely colocalized interacting pigmentary and structural elements generate extensive variation in lizard color

  12. Dynamic performance of doubly-fed induction generator stator flux during consecutive grid voltage variations

    DEFF Research Database (Denmark)

    Zhu, Rongwu; Chen, Zhe; Wu, Xiaojie

    2015-01-01

    For the grid-connected doubly-fed induction generator (DFIG)-based wind turbine, because of the stator connected to the grid directly, the stator flux easily suffers from the effects of grid voltage variations, such as grid disturbances and grid faults. Moreover, since the magnetic field is excited...... reveal that the stator flux can be accumulated by the consecutive variations of the stator voltage, and the instants of grid voltage variations can lead to different amplitudes of the stator flux. In addition, the conventional vector control strategy and the active damping strategy are compared...... by the rotor current, stator flux is also affected by the rotor current. Therefore this study systematically studies the dynamic performances of stator flux under consecutive grid voltage variations and varying rotor currents, and its influence on the performances of the DFIG during grid faults. The analyses...

  13. Note: A 10 Gbps real-time post-processing free physical random number generator chip

    Science.gov (United States)

    Qian, Yi; Liang, Futian; Wang, Xinzhe; Li, Feng; Chen, Lian; Jin, Ge

    2017-09-01

    A random number generator with high data rate, small size, and low power consumption is essential for a certain quantum key distribution (QKD) system. We designed a 10 Gbps random number generator ASIC, TRNG2016, for the QKD system. With a 6 mm × 6 mm QFN48 package, TRNG2016 has 10 independent physical random number generation channels, and each channel can work at a fixed frequency up to 1 Gbps. The random number generated by TRNG2016 can pass the NIST statistical tests without any post-processing. With 3.3 V IO power supply and 1.2 V core power supply, the typical power consumption of TRNG2016 is 773 mW with 10 channels on and running at 1 Gbps data rate.

  14. Note: Fully integrated 3.2 Gbps quantum random number generator with real-time extraction

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiao-Guang; Nie, You-Qi; Liang, Hao; Zhang, Jun, E-mail: zhangjun@ustc.edu.cn; Pan, Jian-Wei [Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Zhou, Hongyi; Ma, Xiongfeng [Center for Quantum Information, Institute for Interdisciplinary Information Sciences, Tsinghua University, Beijing 100084 (China)

    2016-07-15

    We present a real-time and fully integrated quantum random number generator (QRNG) by measuring laser phase fluctuations. The QRNG scheme based on laser phase fluctuations is featured for its capability of generating ultra-high-speed random numbers. However, the speed bottleneck of a practical QRNG lies on the limited speed of randomness extraction. To close the gap between the fast randomness generation and the slow post-processing, we propose a pipeline extraction algorithm based on Toeplitz matrix hashing and implement it in a high-speed field-programmable gate array. Further, all the QRNG components are integrated into a module, including a compact and actively stabilized interferometer, high-speed data acquisition, and real-time data post-processing and transmission. The final generation rate of the QRNG module with real-time extraction can reach 3.2 Gbps.

  15. Bayesian and variational Bayesian approaches for flows in heterogeneous random media

    Science.gov (United States)

    Yang, Keren; Guha, Nilabja; Efendiev, Yalchin; Mallick, Bani K.

    2017-09-01

    In this paper, we study porous media flows in heterogeneous stochastic media. We propose an efficient forward simulation technique that is tailored for variational Bayesian inversion. As a starting point, the proposed forward simulation technique decomposes the solution into the sum of separable functions (with respect to randomness and the space), where each term is calculated based on a variational approach. This is similar to Proper Generalized Decomposition (PGD). Next, we apply a multiscale technique to solve for each term (as in [1]) and, further, decompose the random function into 1D fields. As a result, our proposed method provides an approximation hierarchy for the solution as we increase the number of terms in the expansion and, also, increase the spatial resolution of each term. We use the hierarchical solution distributions in a variational Bayesian approximation to perform uncertainty quantification in the inverse problem. We conduct a detailed numerical study to explore the performance of the proposed uncertainty quantification technique and show the theoretical posterior concentration.

  16. Quantum cryptography using coherent states: Randomized encryption and key generation

    Science.gov (United States)

    Corndorf, Eric

    objectives of key generation and direct data-encryption, a new quantum cryptographic principle is demonstrated wherein keyed coherent-state signal sets are employed. Taking advantage of the fundamental and irreducible quantum-measurement noise of coherent states, these schemes do not require the users to measure the influence of an attacker. Experimental key-generation and data encryption schemes based on these techniques, which are compatible with today's WDM fiber-optic telecommunications infrastructure, are implemented and analyzed.

  17. Quantum random number generator based on quantum nature of vacuum fluctuations

    Science.gov (United States)

    Ivanova, A. E.; Chivilikhin, S. A.; Gleim, A. V.

    2017-11-01

    Quantum random number generator (QRNG) allows obtaining true random bit sequences. In QRNG based on quantum nature of vacuum, optical beam splitter with two inputs and two outputs is normally used. We compare mathematical descriptions of spatial beam splitter and fiber Y-splitter in the quantum model for QRNG, based on homodyne detection. These descriptions were identical, that allows to use fiber Y-splitters in practical QRNG schemes, simplifying the setup. Also we receive relations between the input radiation and the resulting differential current in homodyne detector. We experimentally demonstrate possibility of true random bits generation by using QRNG based on homodyne detection with Y-splitter.

  18. Modal generation of the design parameters of an elastic spacecraft by the random search method

    Science.gov (United States)

    Titov, B. A.

    A method for the modal generation of the dynamic properties of an elastic spacecraft is proposed which is based on algorithms of random search in the space of design parameters. A practical implementation of this approach is illustrated by an example. It is shown that the modal parameter generation procedure based on the random search solves the problem of parameter selection. However, as in any other method, the accuracy of the computation of matrix elements is largely determined by the initial set of permissible values and the number of random samples in determining the subgradient of the objective function.

  19. Superresolution with compound Markov random fields via the variational EM algorithm.

    Science.gov (United States)

    Kanemura, Atsunori; Maeda, Shin-ichi; Ishii, Shin

    2009-09-01

    This study deals with a reconstruction-type superresolution problem and the accompanying image registration problem simultaneously. We propose a Bayesian approach in which the prior is modeled as a compound Gaussian Markov random field (MRF) and marginalization is performed over unknown variables to avoid overfitting. Our algorithm not only avoids overfitting, but also preserves discontinuity in the estimated image, unlike existing single-layer Gaussian MRF models for Bayesian superresolution. Maximum-marginal-likelihood estimation of the registration parameters is carried out using a variational EM algorithm where hidden variables are marginalized out, and the posterior distribution is variationally approximated by a factorized trial distribution. High-resolution image estimates are obtained through the process of posterior computation in the EM algorithm. Experiments show that our Bayesian approach with the two-layer compound model exhibits better performance both in quantitative measures and visual quality than the single-layer model.

  20. On the design of henon and logistic map-based random number generator

    Science.gov (United States)

    Magfirawaty; Suryadi, M. T.; Ramli, Kalamullah

    2017-10-01

    The key sequence is one of the main elements in the cryptosystem. True Random Number Generators (TRNG) method is one of the approaches to generating the key sequence. The randomness source of the TRNG divided into three main groups, i.e. electrical noise based, jitter based and chaos based. The chaos based utilizes a non-linear dynamic system (continuous time or discrete time) as an entropy source. In this study, a new design of TRNG based on discrete time chaotic system is proposed, which is then simulated in LabVIEW. The principle of the design consists of combining 2D and 1D chaotic systems. A mathematical model is implemented for numerical simulations. We used comparator process as a harvester method to obtain the series of random bits. Without any post processing, the proposed design generated random bit sequence with high entropy value and passed all NIST 800.22 statistical tests.

  1. 640-Gbit/s fast physical random number generation using a broadband chaotic semiconductor laser

    Science.gov (United States)

    Zhang, Limeng; Pan, Biwei; Chen, Guangcan; Guo, Lu; Lu, Dan; Zhao, Lingjuan; Wang, Wei

    2017-04-01

    An ultra-fast physical random number generator is demonstrated utilizing a photonic integrated device based broadband chaotic source with a simple post data processing method. The compact chaotic source is implemented by using a monolithic integrated dual-mode amplified feedback laser (AFL) with self-injection, where a robust chaotic signal with RF frequency coverage of above 50 GHz and flatness of ±3.6 dB is generated. By using 4-least significant bits (LSBs) retaining from the 8-bit digitization of the chaotic waveform, random sequences with a bit-rate up to 640 Gbit/s (160 GS/s × 4 bits) are realized. The generated random bits have passed each of the fifteen NIST statistics tests (NIST SP800-22), indicating its randomness for practical applications.

  2. Pseudo-Random Number Generators for Vector Processors and Multicore Processors

    DEFF Research Database (Denmark)

    Fog, Agner

    2015-01-01

    Large scale Monte Carlo applications need a good pseudo-random number generator capable of utilizing both the vector processing capabilities and multiprocessing capabilities of modern computers in order to get the maximum performance. The requirements for such a generator are discussed. New ways ...

  3. Delay line length selection in generating fast random numbers with a chaotic laser.

    Science.gov (United States)

    Zhang, Jianzhong; Wang, Yuncai; Xue, Lugang; Hou, Jiayin; Zhang, Beibei; Wang, Anbang; Zhang, Mingjiang

    2012-04-10

    The chaotic light signals generated by an external cavity semiconductor laser have been experimentally demonstrated to extract fast random numbers. However, the photon round-trip time in the external cavity can cause the occurrence of the periodicity in random sequences. To overcome it, the exclusive-or operation on corresponding random bits in samples of the chaotic signal and its time-delay signal from a chaotic laser is required. In this scheme, the proper selection of delay length is a key issue. By doing a large number of experiments and theoretically analyzing the interplay between the Runs test and the threshold value of the autocorrelation function, we find when the corresponding delay time of autocorrelation trace with the correlation coefficient of less than 0.007 is considered as the delay time between the chaotic signal and its time-delay signal, streams of random numbers can be generated with verified randomness.

  4. Novel Complete Probabilistic Models of Random Variation in High Frequency Performance of Nanoscale MOSFET

    Directory of Open Access Journals (Sweden)

    Rawid Banchuin

    2013-01-01

    Full Text Available The novel probabilistic models of the random variations in nanoscale MOSFET's high frequency performance defined in terms of gate capacitance and transition frequency have been proposed. As the transition frequency variation has also been considered, the proposed models are considered as complete unlike the previous one which take only the gate capacitance variation into account. The proposed models have been found to be both analytic and physical level oriented as they are the precise mathematical expressions in terms of physical parameters. Since the up-to-date model of variation in MOSFET's characteristic induced by physical level fluctuation has been used, part of the proposed models for gate capacitance is more accurate and physical level oriented than its predecessor. The proposed models have been verified based on the 65 nm CMOS technology by using the Monte-Carlo SPICE simulations of benchmark circuits and Kolmogorov-Smirnov tests as highly accurate since they fit the Monte-Carlo-based analysis results with 99% confidence. Hence, these novel models have been found to be versatile for the statistical/variability aware analysis/design of nanoscale MOSFET-based analog/mixed signal circuits and systems.

  5. Concurrent Generation of Pseudo Random Numbers with LFSR of Fibonacci and Galois Type

    OpenAIRE

    Emina I. Milovanović; Stojčev, Mile K.; Igor Ž. Milovanović; Tatjana R. Nikolić; Zoran Stamenković

    2016-01-01

    We have considered implementation of parallel test pattern generator based on a linear feedback shift register (LFSR) with multiple outputs used as a building block in built-in-self-test (BIST) design within SoC. The proposed design can drive several circuits under test (CUT) simultaneously. The mathematical procedure for concurrent pseudo random number (PRN) generation is described. We have implemented LFSRs that generate two and three PRNs in FPGA and ASIC technology. The design was tested ...

  6. Sensor fault detection and isolation in doubly-fed induction generators accounting for parameter variations

    Energy Technology Data Exchange (ETDEWEB)

    Galvez-Carrillo, Manuel; Kinnaert, Michel [Dept. of Control Engineering and System Analysis, Universite Libre de Bruxelles (ULB), 50 Av. F.D. Roosevelt, CP 165/55, B-1050 Brussels (Belgium)

    2011-05-15

    A fault detection and isolation (FDI) system for monitoring rotor current sensors in a doubly-fed induction generator (DFIG) for wind turbine applications is presented. The FDI system is designed so that the effect of parameter variations (resistances and inductances) is minimized. The residual generation is based on the generalized observer scheme (GOS) including parameter estimation. A decision system made of a combination of vector CUSUM (Cumulative sum) algorithms is used to process the residual vector and to achieve detection and isolation of incipient (small magnitude) faults. The approach is validated using signals obtained from a simulated vector-controlled DFIG. (author)

  7. Random laser action with coherent feedback via second-harmonic generation

    CERN Document Server

    Qiao, Yanqi; Cai, Zengyan; Chen, Xianfeng

    2016-01-01

    The random laser action with coherent feedback by second-harmonic generation (SHG) was experimentally demonstrated in this paper. Compared with the conventional random laser action based on photoluminescence effect, which needs strong photoresponse in the active medium and has a fixed response waveband due to the inherent energy level structure of the material, this random SHG laser action indicates a possible confinement of the nonlinear signal with ring cavities and widens the response waveband due to the flexible frequency conversion in nonlinear process. The combination of coherent random laser and nonlinear optics will provide us another possible way to break phase-matching limitations, with fiber or feedback-based wavefront shaping method to transmit the emission signal directionally. This work suggests potential applications in band-tunable random laser, phase-matching-free nonlinear optics and even brings in new consideration about random nonlinear optics (RNO).

  8. Random Number Generation and Executive Functions in Parkinson's Disease: An Event-Related Brain Potential Study.

    Science.gov (United States)

    Münte, Thomas F; Joppich, Gregor; Däuper, Jan; Schrader, Christoph; Dengler, Reinhard; Heldmann, Marcus

    2015-01-01

    The generation of random sequences is considered to tax executive functions and has been reported to be impaired in Parkinson's disease (PD) previously. To assess the neurophysiological markers of random number generation in PD. Event-related potentials (ERP) were recorded in 12 PD patients and 12 age-matched normal controls (NC) while either engaging in random number generation (RNG) by pressing the number keys on a computer keyboard in a random sequence or in ordered number generation (ONG) necessitating key presses in the canonical order. Key presses were paced by an external auditory stimulus at a rate of 1 tone every 1800 ms. As a secondary task subjects had to monitor the tone-sequence for a particular target tone to which the number "0" key had to be pressed. This target tone occurred randomly and infrequently, thus creating a secondary oddball task. Behaviorally, PD patients showed an increased tendency to count in steps of one as well as a tendency towards repetition avoidance. Electrophysiologically, the amplitude of the P3 component of the ERP to the target tone of the secondary task was reduced during RNG in PD but not in NC. The behavioral findings indicate less random behavior in PD while the ERP findings suggest that this impairment comes about, because attentional resources are depleted in PD.

  9. Early stage hot spot analysis through standard cell base random pattern generation

    Science.gov (United States)

    Jeon, Joong-Won; Song, Jaewan; Kim, Jeong-Lim; Park, Seongyul; Yang, Seung-Hune; Lee, Sooryong; Kang, Hokyu; Madkour, Kareem; ElManhawy, Wael; Lee, SeungJo; Kwan, Joe

    2017-04-01

    Due to limited availability of DRC clean patterns during the process and RET recipe development, OPC recipes are not tested with high pattern coverage. Various kinds of pattern can help OPC engineer to detect sensitive patterns to lithographic effects. Random pattern generation is needed to secure robust OPC recipe. However, simple random patterns without considering real product layout style can't cover patterning hotspot in production levels. It is not effective to use them for OPC optimization thus it is important to generate random patterns similar to real product patterns. This paper presents a strategy for generating random patterns based on design architecture information and preventing hotspot in early process development stage through a tool called Layout Schema Generator (LSG). Using LSG, we generate standard cell based on random patterns reflecting real design cell structure - fin pitch, gate pitch and cell height. The output standard cells from LSG are applied to an analysis methodology to assess their hotspot severity by assigning a score according to their optical image parameters - NILS, MEEF, %PV band and thus potential hotspots can be defined by determining their ranking. This flow is demonstrated on Samsung 7nm technology optimizing OPC recipe and early enough in the process avoiding using problematic patterns.

  10. A revision of the subtract-with-borrow random number generators

    Science.gov (United States)

    Sibidanov, Alexei

    2017-12-01

    The most popular and widely used subtract-with-borrow generator, also known as RANLUX, is reimplemented as a linear congruential generator using large integer arithmetic with the modulus size of 576 bits. Modern computers, as well as the specific structure of the modulus inferred from RANLUX, allow for the development of a fast modular multiplication - the core of the procedure. This was previously believed to be slow and have too high cost in terms of computing resources. Our tests show a significant gain in generation speed which is comparable with other fast, high quality random number generators. An additional feature is the fast skipping of generator states leading to a seeding scheme which guarantees the uniqueness of random number sequences. Licensing provisions: GPLv3 Programming language: C++, C, Assembler

  11. Genetic variations of Lansium domesticum Corr. accessions from Java, Sumatra and Ceram based on Random Amplified Polymorphic DNA fingerprints

    Directory of Open Access Journals (Sweden)

    KUSUMADEWI SRI YULITA

    2011-07-01

    Full Text Available Yulita KS (2011 Genetic variations of Lansium domesticum Corr. accessions from Java, Bengkulu and Ceram based on Random Amplified Polymorphic DNA fingerprints. Biodiversitas 12: 125-130. Duku (Lansium domesticum Corr. is one of popular tropical fruits in SE Asia. The spesies has three varieties, known as duku, langsat and kokosan; and duku is the most popular one for being the sweetiest fruit. Indonesia has several local varieties of duku, such as duku Condet, duku Sumber and duku Palembang. This present study aimed to assess genetic diversity of 47 accessions of duku from Java, Sumatra, and Ceram based on RAPD fingerprints. Ten RAPD’s primers were initially screened and five were selected for the analysis. These five primers (OPA 7, 13, 18, OPB 7, and OPN 12 generated 53 scorable bands with an average of 10.6 polymorphic fragment per primer. Percentage of polymorphism ranged from 16.89% (OPA 7 and OPN 12 to 24.54% (OPB 7 with an average of 20.16% polymorphism. OPB 7 at 450 bp was exclusively possessed by accession 20 (Java, OPA 18 at 500 bp was by accession 6 (Java, 550 bp by 3 clones from Bengkulu. While OPN 12 at 300 bp and OPA 13 at 450 bp were shared among the accessions. Clustering analysis was performed based on RAPD profiles using the UPGMA method. The range of genetic similarity value among accessions was 0.02-0.65 suggesting high variation of gene pool existed among accessions.

  12. The effects of cross-generational and cross-dialectal variation on vowel identification and classification.

    Science.gov (United States)

    Jacewicz, Ewa; Fox, Robert Allen

    2012-02-01

    Cross-generational and cross-dialectal variation in vowels among speakers of American English was examined in terms of vowel identification by listeners and vowel classification using pattern recognition. Listeners from Western North Carolina and Southeastern Wisconsin identified 12 vowel categories produced by 120 speakers stratified by age (old adults, young adults, and children), gender, and dialect. The vowels /ɝ, o, ʊ, u/ were well identified by both groups of listeners. The majority of confusions were for the front /i, ɪ, e, ɛ, æ/, the low back /ɑ, ɔ/ and the monophthongal North Carolina /aɪ/. For selected vowels, generational differences in acoustic vowel characteristics were perceptually salient, suggesting listeners' responsiveness to sound change. Female exemplars and native-dialect variants produced higher identification rates. Linear discriminant analyses which examined dialect and generational classification accuracy showed that sampling the formant pattern at vowel midpoint only is insufficient to separate the vowels. Two sample points near onset and offset provided enough information for successful classification. The models trained on one dialect classified the vowels from the other dialect with much lower accuracy. The results strongly support the importance of dynamic information in accurate classification of cross-generational and cross-dialectal variations. © 2012 Acoustical Society of America

  13. Compact quantum random number generator based on superluminescent light-emitting diodes

    Science.gov (United States)

    Wei, Shihai; Yang, Jie; Fan, Fan; Huang, Wei; Li, Dashuang; Xu, Bingjie

    2017-12-01

    By measuring the amplified spontaneous emission (ASE) noise of the superluminescent light emitting diodes, we propose and realize a quantum random number generator (QRNG) featured with practicability. In the QRNG, after the detection and amplification of the ASE noise, the data acquisition and randomness extraction which is integrated in a field programmable gate array (FPGA) are both implemented in real-time, and the final random bit sequences are delivered to a host computer with a real-time generation rate of 1.2 Gbps. Further, to achieve compactness, all the components of the QRNG are integrated on three independent printed circuit boards with a compact design, and the QRNG is packed in a small enclosure sized 140 mm × 120 mm × 25 mm. The final random bit sequences can pass all the NIST-STS and DIEHARD tests.

  14. Quantum random number generation enhanced by weak-coherent states interference.

    Science.gov (United States)

    Ferreira da Silva, T; Xavier, G B; Amaral, G C; Temporão, G P; von der Weid, J P

    2016-08-22

    We propose and demonstrate a technique for quantum random number generation based on the random population of the output spatial modes of a beam splitter when both inputs are simultaneously fed with indistinguishable weak coherent states. We simulate and experimentally validate the probability of generation of random bits as a function of the average photon number per input, and compare it to the traditional approach of a single weak coherent state transmitted through a beam-splitter, showing an improvement of up to 32%. The ensuing interference phenomenon reduces the probability of coincident counts between the detectors associated with bits 0 and 1, thus increasing the probability of occurrence of a valid output. A long bit string is assessed by a standard randomness test suite with good confidence. Our proposal can be easily implemented and opens attractive performance gains without a significant trade-off.

  15. A Bidirectional Generalized Synchronization Theorem-Based Chaotic Pseudo-random Number Generator

    Directory of Open Access Journals (Sweden)

    Han Shuangshuang

    2013-07-01

    Full Text Available Based on a bidirectional generalized synchronization theorem for discrete chaos system, this paper introduces a new 5-dimensional bidirectional generalized chaos synchronization system (BGCSDS, whose prototype is a novel chaotic system introduced in [12]. Numerical simulation showed that two pair variables of the BGCSDS achieve generalized chaos synchronization via a transform H.A chaos-based pseudo-random number generator (CPNG was designed by the new BGCSDS. Using the FIPS-140-2 tests issued by the National Institute of Standard and Technology (NIST verified the randomness of the 1000 binary number sequences generated via the CPNG and the RC4 algorithm respectively. The results showed that all the tested sequences passed the FIPS-140-2 tests. The confidence interval analysis showed the statistical properties of the randomness of the sequences generated via the CPNG and the RC4 algorithm do not have significant differences.

  16. Generating Variable and Random Schedules of Reinforcement Using Microsoft Excel Macros

    OpenAIRE

    Bancroft, Stacie L; Bourret, Jason C

    2008-01-01

    Variable reinforcement schedules are used to arrange the availability of reinforcement following varying response ratios or intervals of time. Random reinforcement schedules are subtypes of variable reinforcement schedules that can be used to arrange the availability of reinforcement at a constant probability across number of responses or time. Generating schedule values for variable and random reinforcement schedules can be difficult. The present article describes the steps necessary to writ...

  17. Theory of fast nondeterministic physical random-bit generation with chaotic lasers.

    Science.gov (United States)

    Harayama, Takahisa; Sunada, Satoshi; Yoshimura, Kazuyuki; Muramatsu, Jun; Arai, Ken-ichi; Uchida, Atsushi; Davis, Peter

    2012-04-01

    We theoretically show that completely stochastic fast physical random bit generation at a rate of more than one gigabit per second can be realized by using lasers with optical delayed feedback which creates high-dimensional chaos of laser light outputs. The theory is based on the mixing property of chaos, which transduces microscopic quantum noise of spontaneous emission in lasers into random transitions between discrete macroscopic states.

  18. Graphene based widely-tunable and singly-polarized pulse generation with random fiber lasers

    Science.gov (United States)

    Yao, B. C.; Rao, Y. J.; Wang, Z. N.; Wu, Y.; Zhou, J. H.; Wu, H.; Fan, M. Q.; Cao, X. L.; Zhang, W. L.; Chen, Y. F.; Li, Y. R.; Churkin, D.; Turitsyn, S.; Wong, C. W.

    2015-12-01

    Pulse generation often requires a stabilized cavity and its corresponding mode structure for initial phase-locking. Contrastingly, modeless cavity-free random lasers provide new possibilities for high quantum efficiency lasing that could potentially be widely tunable spectrally and temporally. Pulse generation in random lasers, however, has remained elusive since the discovery of modeless gain lasing. Here we report coherent pulse generation with modeless random lasers based on the unique polarization selectivity and broadband saturable absorption of monolayer graphene. Simultaneous temporal compression of cavity-free pulses are observed with such a polarization modulation, along with a broadly-tunable pulsewidth across two orders of magnitude down to 900 ps, a broadly-tunable repetition rate across three orders of magnitude up to 3 MHz, and a singly-polarized pulse train at 41 dB extinction ratio, about an order of magnitude larger than conventional pulsed fiber lasers. Moreover, our graphene-based pulse formation also demonstrates robust pulse-to-pulse stability and wide-wavelength operation due to the cavity-less feature. Such a graphene-based architecture not only provides a tunable pulsed random laser for fiber-optic sensing, speckle-free imaging, and laser-material processing, but also a new way for the non-random CW fiber lasers to generate widely tunable and singly-polarized pulses.

  19. Random fields generation on the GPU with the spectral turning bands method

    Science.gov (United States)

    Hunger, L.; Cosenza, B.; Kimeswenger, S.; Fahringer, T.

    2014-08-01

    Random field (RF) generation algorithms are of paramount importance for many scientific domains, such as astrophysics, geostatistics, computer graphics and many others. Some examples are the generation of initial conditions for cosmological simulations or hydrodynamical turbulence driving. In the latter a new random field is needed every time-step. Current approaches commonly make use of 3D FFT (Fast Fourier Transform) and require the whole generated field to be stored in memory. Moreover, they are limited to regular rectilinear meshes and need an extra processing step to support non-regular meshes. In this paper, we introduce TBARF (Turning BAnd Random Fields), a RF generation algorithm based on the turning band method that is optimized for massively parallel hardware such as GPUs. Our algorithm replaces the 3D FFT with a lower order, one-dimensional FFT followed by a projection step, and is further optimized with loop unrolling and blocking. We show that TBARF can easily generate RF on non-regular (non uniform) meshes and can afford mesh sizes bigger than the available GPU memory by using a streaming, out-of-core approach. TBARF is 2 to 5 times faster than the traditional methods when generating RFs with more than 16M cells. It can also generate RF on non-regular meshes, and has been successfully applied to two real case scenarios: planetary nebulae and cosmological simulations.

  20. Random bit generation using an optically injected semiconductor laser in chaos with oversampling.

    Science.gov (United States)

    Li, Xiao-Zhou; Chan, Sze-Chun

    2012-06-01

    Random bit generation is experimentally demonstrated using a semiconductor laser driven into chaos by optical injection. The laser is not subject to any feedback so that the chaotic waveform possesses very little autocorrelation. Random bit generation is achieved at a sampling rate of 10 GHz even when only a fractional bandwidth of 1.5 GHz within a much broader chaotic bandwidth is digitized. By retaining only 3 least significant bits per sample, an output bit rate of 30 Gbps is attained. The approach requires no complicated postprocessing and has no stringent requirement on the electronics bandwidth.

  1. Fortran code for generating random probability vectors, unitaries, and quantum states

    Directory of Open Access Journals (Sweden)

    Jonas eMaziero

    2016-03-01

    Full Text Available The usefulness of generating random configurations is recognized in many areas of knowledge. Fortran was born for scientific computing and has been one of the main programming languages in this area since then. And several ongoing projects targeting towards its betterment indicate that it will keep this status in the decades to come. In this article, we describe Fortran codes produced, or organized, for the generation of the following random objects: numbers, probability vectors, unitary matrices, and quantum state vectors and density matrices. Some matrix functions are also included and may be of independent interest.

  2. Variations in reporting of outcomes in randomized trials on diet and physical activity in pregnancy

    DEFF Research Database (Denmark)

    Rogozińska, Ewelina; Marlin, Nadine; Yang, Fen

    2017-01-01

    AIM: Trials on diet and physical activity in pregnancy report on various outcomes. We aimed to assess the variations in outcomes reported and their quality in trials on lifestyle interventions in pregnancy. METHODS: We searched major databases without language restrictions for randomized controlled...... trials on diet and physical activity-based interventions in pregnancy up to March 2015. Two independent reviewers undertook study selection and data extraction. We estimated the percentage of papers reporting 'critically important' and 'important' outcomes. We defined the quality of reporting.......6%, 40/66), were the commonly reported 'critically important' outcomes. Gestational weight gain (84.5%, 56/66) and birth weight (87.9%, 58/66) were reported in most papers, although not considered critically important. The median quality of reporting was 0.60 (interquartile range 0.25, 0...

  3. Correlation between static random access memory power-up state and transistor variation

    Science.gov (United States)

    Takeuchi, Kiyoshi; Mizutani, Tomoko; Saraya, Takuya; Shinohara, Hirofumi; Kobayashi, Masaharu; Hiramoto, Toshiro

    2017-04-01

    The correlation between the static random access memory (SRAM) power-up state (i.e., state 0 or 1 immediately after the power supply is turned on) and cell transistor variation is systematically studied by circuit simulations and mismatch space partitioning. It is revealed that, while both the mismatches of pFETs (pull-up) and nFETs (pull-down and access) contribute, their relative importance changes depending on the voltage ramping speed. The static retention noise margin well correlates with the power-up state only if the ramping speed is sufficiently low. Otherwise, pull-up transistor mismatch dominates the power-up state determination owing to the interference of capacitive current and asymmetrical capacitive coupling of the storage nodes to the ground and power supply.

  4. Random amplified polymorphic DNA analysis and variation of essential oil components of Atractylodes plants.

    Science.gov (United States)

    Kohjyouma, M; Nakajima, S; Namera, A; Shimizu, R; Mizukami, H; Kohda, H

    1997-05-01

    Total DNAs were prepared from the leaves of Atractylodes lancea DE CANDOLLE, A. chinensis KOIDZUMI, A. lancea var. simplicifolia KITAMURA, A. japonica KOIDZUMI ex KITAMURA and A. ovata DE CANDOLLE. The DNAs were subjected to random amplified polymorphic DNA (RAPD) analysis. Some primers showed the definitive polymorphic DNA patterns in A. lancea, A. japonica and A. ovata. The RAPD of A. lancea var. simplicifolia and one of A. chinensis gave similar patterns to those of A. lancea, but one of the other A. chinensis gave a similar pattern to A. japonica. Furthermore, quantitative analysis of atractylon, hinesol, beta-eudesmol and atractylodin in the rhizomes was done using gas chromatography. Though atractylon was detected not only in A. japonica and A. ovata but also in some of A. lancea, their RAPD profiles revealed the presence of intraspecific variation with A. lancea.

  5. An On-Demand Optical Quantum Random Number Generator with In-Future Action and Ultra-Fast Response.

    Science.gov (United States)

    Stipčević, Mario; Ursin, Rupert

    2015-06-09

    Random numbers are essential for our modern information based society e.g. in cryptography. Unlike frequently used pseudo-random generators, physical random number generators do not depend on complex algorithms but rather on a physical process to provide true randomness. Quantum random number generators (QRNG) do rely on a process, which can be described by a probabilistic theory only, even in principle. Here we present a conceptually simple implementation, which offers a 100% efficiency of producing a random bit upon a request and simultaneously exhibits an ultra low latency. A careful technical and statistical analysis demonstrates its robustness against imperfections of the actual implemented technology and enables to quickly estimate randomness of very long sequences. Generated random numbers pass standard statistical tests without any post-processing. The setup described, as well as the theory presented here, demonstrate the maturity and overall understanding of the technology.

  6. Quasi optimal and adaptive sparse grids with control variates for PDEs with random diffusion coefficient

    KAUST Repository

    Tamellini, Lorenzo

    2016-01-05

    In this talk we discuss possible strategies to minimize the impact of the curse of dimensionality effect when building sparse-grid approximations of a multivariate function u = u(y1, ..., yN ). More precisely, we present a knapsack approach , in which we estimate the cost and the error reduction contribution of each possible component of the sparse grid, and then we choose the components with the highest error reduction /cost ratio. The estimates of the error reduction are obtained by either a mixed a-priori / a-posteriori approach, in which we first derive a theoretical bound and then tune it with some inexpensive auxiliary computations (resulting in the so-called quasi-optimal sparse grids ), or by a fully a-posteriori approach (obtaining the so-called adaptive sparse grids ). This framework is very general and can be used to build quasi-optimal/adaptive sparse grids on bounded and unbounded domains (e.g. u depending on uniform and normal random distributions for yn), using both nested and non-nested families of univariate collocation points. We present some theoretical convergence results as well as numerical results showing the efficiency of the proposed approach for the approximation of the solution of elliptic PDEs with random diffusion coefficients. In this context, to treat the case of rough permeability fields in which a sparse grid approach may not be suitable, we propose to use the sparse grids as a control variate in a Monte Carlo simulation.

  7. Generation of sound by Alfven waves with random phases in the solar atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Petrukhin, N.S.; Fainshtein, S.M.

    1976-11-01

    The problem of the excitation of sound by Alfven waves meeting in the solar plasma is discussed. Kinetic equations for the interacting waves are derived and analyzed on the assumption that the Alfven waves have random phases. Estimates are given which show the possibility of the generation of LF-pulsations in the solar atmosphere.

  8. Examining Psychokinesis: The Interaction of Human Intention with Random Number Generators--A Meta-Analysis

    Science.gov (United States)

    Bosch, Holger; Steinkamp, Fiona; Boller, Emil

    2006-01-01

    Seance-room and other large-scale psychokinetic phenomena have fascinated humankind for decades. Experimental research has reduced these phenomena to attempts to influence (a) the fall of dice and, later, (b) the output of random number generators (RNGs). The meta-analysis combined 380 studies that assessed whether RNG output correlated with human…

  9. A time series approach to random number generation: Using recurrence quantification analysis to capture executive behavior

    NARCIS (Netherlands)

    Oomens, W.; Maes, J.H.R.; Hasselman, F.W.; Egger, J.I.M.

    2015-01-01

    The concept of executive functions plays a prominent role in contemporary experimental and clinical studies on cognition. One paradigm used in this framework is the random number generation (RNG) task, the execution of which demands aspects of executive functioning, specifically inhibition and

  10. Forward modeling of gravity data using geostatistically generated subsurface density variations

    Science.gov (United States)

    Phelps, Geoffrey

    2016-01-01

    Using geostatistical models of density variations in the subsurface, constrained by geologic data, forward models of gravity anomalies can be generated by discretizing the subsurface and calculating the cumulative effect of each cell (pixel). The results of such stochastically generated forward gravity anomalies can be compared with the observed gravity anomalies to find density models that match the observed data. These models have an advantage over forward gravity anomalies generated using polygonal bodies of homogeneous density because generating numerous realizations explores a larger region of the solution space. The stochastic modeling can be thought of as dividing the forward model into two components: that due to the shape of each geologic unit and that due to the heterogeneous distribution of density within each geologic unit. The modeling demonstrates that the internally heterogeneous distribution of density within each geologic unit can contribute significantly to the resulting calculated forward gravity anomaly. Furthermore, the stochastic models match observed statistical properties of geologic units, the solution space is more broadly explored by producing a suite of successful models, and the likelihood of a particular conceptual geologic model can be compared. The Vaca Fault near Travis Air Force Base, California, can be successfully modeled as a normal or strike-slip fault, with the normal fault model being slightly more probable. It can also be modeled as a reverse fault, although this structural geologic configuration is highly unlikely given the realizations we explored.

  11. Spectral turning bands for efficient Gaussian random fields generation on GPUs and accelerators

    Science.gov (United States)

    Hunger, L.; Cosenza, B.; Kimeswenger, S.; Fahringer, T.

    2015-11-01

    A random field (RF) is a set of correlated random variables associated with different spatial locations. RF generation algorithms are of crucial importance for many scientific areas, such as astrophysics, geostatistics, computer graphics, and many others. Current approaches commonly make use of 3D fast Fourier transform (FFT), which does not scale well for RF bigger than the available memory; they are also limited to regular rectilinear meshes. We introduce random field generation with the turning band method (RAFT), an RF generation algorithm based on the turning band method that is optimized for massively parallel hardware such as GPUs and accelerators. Our algorithm replaces the 3D FFT with a lower-order, one-dimensional FFT followed by a projection step and is further optimized with loop unrolling and blocking. RAFT can easily generate RF on non-regular (non-uniform) meshes and efficiently produce fields with mesh sizes bigger than the available device memory by using a streaming, out-of-core approach. Our algorithm generates RF with the correct statistical behavior and is tested on a variety of modern hardware, such as NVIDIA Tesla, AMD FirePro and Intel Phi. RAFT is faster than the traditional methods on regular meshes and has been successfully applied to two real case scenarios: planetary nebulae and cosmological simulations.

  12. Performance of university students on random number generation at different rates to evaluate executive functions

    Directory of Open Access Journals (Sweden)

    Hamdan Amer C.

    2004-01-01

    Full Text Available OBJECTIVE: To evaluate the performance of adult young subjects in a Random Number Generation (RNG task by controlling the response speed (RS. METHOD: Sixty-nine university students of both sexes took part in the experiment (25.05 ± 6.71 year-old. Participants were alloted into 3 groups which differed in RS rates to generate numbers: 1, 2 and 4 seconds to generate each number. A digital metronomer was used to control RS. Participants were asked to generate 100 numbers. The responses were mensured through Evans's RNG Index. RESULTS: There were statistically significant differences among the groups [F (3, 68 = 7.120; p < .05]. Differences were localized between 1 and 2 seconds (p = 0.004 and between 1 and 4 seconds (p = 0.006. No differences were observed between 2 and 4 seconds (p = 0.985. CONCLUSION: The present results suggest that the response speed in production of random numbers influences the performance of the Random Numbers Generation task.

  13. Synchronization of random bit generators based on coupled chaotic lasers and application to cryptography.

    Science.gov (United States)

    Kanter, Ido; Butkovski, Maria; Peleg, Yitzhak; Zigzag, Meital; Aviad, Yaara; Reidler, Igor; Rosenbluh, Michael; Kinzel, Wolfgang

    2010-08-16

    Random bit generators (RBGs) constitute an important tool in cryptography, stochastic simulations and secure communications. The later in particular has some difficult requirements: high generation rate of unpredictable bit strings and secure key-exchange protocols over public channels. Deterministic algorithms generate pseudo-random number sequences at high rates, however, their unpredictability is limited by the very nature of their deterministic origin. Recently, physical RBGs based on chaotic semiconductor lasers were shown to exceed Gbit/s rates. Whether secure synchronization of two high rate physical RBGs is possible remains an open question. Here we propose a method, whereby two fast RBGs based on mutually coupled chaotic lasers, are synchronized. Using information theoretic analysis we demonstrate security against a powerful computational eavesdropper, capable of noiseless amplification, where all parameters are publicly known. The method is also extended to secure synchronization of a small network of three RBGs.

  14. Dynamics of a semiconductor laser with polarization-rotated feedback and its utilization for random bit generation.

    Science.gov (United States)

    Oliver, Neus; Soriano, Miguel C; Sukow, David W; Fischer, Ingo

    2011-12-01

    Chaotic semiconductor lasers have been proven attractive for fast random bit generation. To follow this strategy, simple robust systems and a systematic approach determining the required dynamical properties and most suitable conditions for this application are needed. We show that dynamics of a single mode laser with polarization-rotated feedback are optimal for random bit generation when characterized simultaneously by a broad power spectrum and low autocorrelation. We observe that successful random bit generation also is sensitive to digitization and postprocessing procedures. Applying the identified criteria, we achieve fast random bit generation rates (up to 4 Gbit/s) with minimal postprocessing. © 2011 Optical Society of America

  15. An adaptive random search for short term generation scheduling with network constraints.

    Directory of Open Access Journals (Sweden)

    J A Marmolejo

    Full Text Available This paper presents an adaptive random search approach to address a short term generation scheduling with network constraints, which determines the startup and shutdown schedules of thermal units over a given planning horizon. In this model, we consider the transmission network through capacity limits and line losses. The mathematical model is stated in the form of a Mixed Integer Non Linear Problem with binary variables. The proposed heuristic is a population-based method that generates a set of new potential solutions via a random search strategy. The random search is based on the Markov Chain Monte Carlo method. The main key of the proposed method is that the noise level of the random search is adaptively controlled in order to exploring and exploiting the entire search space. In order to improve the solutions, we consider coupling a local search into random search process. Several test systems are presented to evaluate the performance of the proposed heuristic. We use a commercial optimizer to compare the quality of the solutions provided by the proposed method. The solution of the proposed algorithm showed a significant reduction in computational effort with respect to the full-scale outer approximation commercial solver. Numerical results show the potential and robustness of our approach.

  16. PUFKEY: A High-Security and High-Throughput Hardware True Random Number Generator for Sensor Networks

    Directory of Open Access Journals (Sweden)

    Dongfang Li

    2015-10-01

    Full Text Available Random number generators (RNG play an important role in many sensor network systems and applications, such as those requiring secure and robust communications. In this paper, we develop a high-security and high-throughput hardware true random number generator, called PUFKEY, which consists of two kinds of physical unclonable function (PUF elements. Combined with a conditioning algorithm, true random seeds are extracted from the noise on the start-up pattern of SRAM memories. These true random seeds contain full entropy. Then, the true random seeds are used as the input for a non-deterministic hardware RNG to generate a stream of true random bits with a throughput as high as 803 Mbps. The experimental results show that the bitstream generated by the proposed PUFKEY can pass all standard national institute of standards and technology (NIST randomness tests and is resilient to a wide range of security attacks.

  17. PUFKEY: a high-security and high-throughput hardware true random number generator for sensor networks.

    Science.gov (United States)

    Li, Dongfang; Lu, Zhaojun; Zou, Xuecheng; Liu, Zhenglin

    2015-10-16

    Random number generators (RNG) play an important role in many sensor network systems and applications, such as those requiring secure and robust communications. In this paper, we develop a high-security and high-throughput hardware true random number generator, called PUFKEY, which consists of two kinds of physical unclonable function (PUF) elements. Combined with a conditioning algorithm, true random seeds are extracted from the noise on the start-up pattern of SRAM memories. These true random seeds contain full entropy. Then, the true random seeds are used as the input for a non-deterministic hardware RNG to generate a stream of true random bits with a throughput as high as 803 Mbps. The experimental results show that the bitstream generated by the proposed PUFKEY can pass all standard national institute of standards and technology (NIST) randomness tests and is resilient to a wide range of security attacks.

  18. Growth variation and heritability in a second-generation Eucalyptus urophylla progeny test at Lad Krating Plantation, Chachoengsao province, Thailand

    Directory of Open Access Journals (Sweden)

    Lucky Nhlanhla Dlamini

    2017-06-01

    Full Text Available In Thailand, Eucalyptus urophylla was introduced with the main purpose of supplying raw material for pulp and chip wood production. The demand for genetically improved seed is increasing to support high productivity plantation establishment. One of the tree improvement activities established to meet the high demand for improved seed was a second generation progeny test at Lad Krating Plantation, Thailand to provide the best material for the successful plantation program. The aim of the current study was to compare growth variation of the first and second generation of Eucalyptus urophylla progeny that could provide information on suitable families for improved quality seed. The progeny test comprised the best 45 half-sib families selected from 80 half-sib families of the first-generation progeny test. The design of the progeny test was a randomized and complete block design (16 trees/plot × 45 plots/block × 9 blocks, with 4 rows of 4 trees at a spacing of 2 m × 1 m. Growth was assessed at age 3 yr. The average height and diameter at breast height over bark (DBH, was 13.72 m, and 8.75 cm, respectively. There were highly significant (p < 0.01 differences among provenances and families in both height and DBH. The individual heritability values for height and DBH were 0.48 and 0.60, respectively. The family heritability values for height and DBH were 0.98 and 0.99, respectively. These 45 half-sib families proved to be genetically superior ensuring higher productivity and contributing to the success of the Forest Industry Organization plantation at Lad Krating.

  19. Random variation in voluntary dry matter intake and effect of day length on feed intake capacity in growing cattle

    DEFF Research Database (Denmark)

    Ingvartsen, Klaus Lønne; Andersen, Refsgaard; Foldager, John

    1992-01-01

    in fifteen bulls, steers and heifers, respectively, fed a complete diet ad libitum. The diet was based on chopped straw formulated to secure physical regulation of feed intake. Total random variation of recorded VDMI corresponded to a coefficient of variation (CV) of 24.6%. Two thirds of this variation...... was increased by 0.32% per hour increase in day length. This is in agreement with the increase found in reviewed literature when photoperiod was manipulated artificially. Practical application of the results for monitoring purposes are exemplified and discussed....

  20. An Architecturally Constrained Model of Random Number Generation and its Application to Modelling the Effect of Generation Rate

    Directory of Open Access Journals (Sweden)

    Nicholas J. Sexton

    2014-07-01

    Full Text Available Random number generation (RNG is a complex cognitive task for human subjects, requiring deliberative control to avoid production of habitual, stereotyped sequences. Under various manipulations (e.g., speeded responding, transcranial magnetic stimulation, or neurological damage the performance of human subjects deteriorates, as reflected in a number of qualitatively distinct, dissociable biases. For example, the intrusion of stereotyped behaviour (e.g., counting increases at faster rates of generation. Theoretical accounts of the task postulate that it requires the integrated operation of multiple, computationally heterogeneous cognitive control ('executive' processes. We present a computational model of RNG, within the framework of a novel, neuropsychologically-inspired cognitive architecture, ESPro. Manipulating the rate of sequence generation in the model reproduced a number of key effects observed in empirical studies, including increasing sequence stereotypy at faster rates. Within the model, this was due to time limitations on the interaction of supervisory control processes, namely, task setting, proposal of responses, monitoring, and response inhibition. The model thus supports the fractionation of executive function into multiple, computationally heterogeneous processes.

  1. Design of Energy Aware Adder Circuits Considering Random Intra-Die Process Variations

    Directory of Open Access Journals (Sweden)

    Marco Lanuzza

    2011-04-01

    Full Text Available Energy consumption is one of the main barriers to current high-performance designs. Moreover, the increased variability experienced in advanced process technologies implies further timing yield concerns and therefore intensifies this obstacle. Thus, proper techniques to achieve robust designs are a critical requirement for integrated circuit success. In this paper, the influence of intra-die random process variations is analyzed considering the particular case of the design of energy aware adder circuits. Five well known adder circuits were designed exploiting an industrial 45 nm static complementary metal-oxide semiconductor (CMOS standard cell library. The designed adders were comparatively evaluated under different energy constraints. As a main result, the performed analysis demonstrates that, for a given energy budget, simpler circuits (which are conventionally identified as low-energy slow architectures operating at higher power supply voltages can achieve a timing yield significantly better than more complex faster adders when used in low-power design with supply voltages lower than nominal.

  2. Complexity and properties of a multidimensional Cat-Hadamard map for pseudo random number generation

    Science.gov (United States)

    Kim Hue, Ta Thi; Hoang, Thang Manh

    2017-07-01

    This paper presents a novel method to extend the Cat map from 2-dimension to higher dimension using the fast pseudo Hadamard Transform, and the resulted maps are called Cat-Hadamard maps. The complexity and properties of Cat-Hadamard maps are investigated under the point of view for cryptographic applications. In addition, we propose a method for constructing a pseudo random number generator using a novel design concept of the high dimensional Cat map. The simulation results show that the proposed generator fulfilled all the statistic tests of the NIST SP 800-90 A.

  3. [Quantitive variation of polysaccharides and alcohol-soluble extracts in F1 generation of Dendrobium officinale].

    Science.gov (United States)

    Zhang, Xiao-Ling; Liu, Jing-Jing; Wu, Ling-Shang; Si, Jin-Ping; Guo, Ying-Ying; Yu, Jie; Wang, Lin-Hua

    2013-11-01

    Using phenol-sulfuric acid method and hot-dip method of alcohol-soluble extracts, the contents of polysaccharides and alcohol-soluble extracts in 11 F1 generations of Dendrobium officinale were determined. The results showed that the polysaccharides contents in samples collected in May and February were 32.89%-43.07% and 25.77%-35.25%, respectively, while the extracts contents were 2.81%-4.85% and 7.90%-17.40%, respectively. They were significantly different among families. The content of polysaccharides in offspring could be significantly improved by hybridization between parents with low and high polysaccharides contents, and the hybrid vigor was obvious. Cross breeding was an effective way for breeding new varieties with higher polysaccharides contents. Harvest time would significantly affect the contents of polysaccharides and alcohol-soluble extracts. The contents of polysaccharides in families collected in May were higher than those of polysaccharides in families collected in February, but the extracts content had the opposite variation. The extents of quantitative variation of polysaccharides and alcohol-soluble extracts were different among families, and each family had its own rules. It would be significant in giving full play to their role as the excellent varieties and increasing effectiveness by studying on the quantitative accumulation regularity of polysaccharides and alcohol-soluble extracts in superior families (varieties) of D. officinale to determine the best harvesting time.

  4. Generation of random numbers on graphics processors: forced indentation in silico of the bacteriophage HK97.

    Science.gov (United States)

    Zhmurov, A; Rybnikov, K; Kholodov, Y; Barsegov, V

    2011-05-12

    The use of graphics processing units (GPUs) in simulation applications offers a significant speed gain as compared to computations on central processing units (CPUs). Many simulation methods require a large number of independent random variables generated at each step. We present two approaches for implementation of random number generators (RNGs) on a GPU. In the one-RNG-per-thread approach, one RNG produces a stream of random numbers in each thread of execution, whereas the one-RNG-for-all-threads method builds on the ability of different threads to communicate, thus, sharing random seeds across an entire GPU device. We used these approaches to implement Ran2, Hybrid Taus, and Lagged Fibonacci algorithms on a GPU. We profiled the performance of these generators in terms of the computational time, memory usage, and the speedup factor (CPU time/GPU time). These generators have been incorporated into the program for Langevin simulations of biomolecules fully implemented on the GPU. The ∼250-fold computational speedup on the GPU allowed us to carry out single-molecule dynamic force measurements in silico to explore the mechanical properties of the bacteriophage HK97 in the experimental subsecond time scale. We found that the nanomechanical response of HK97 depends on the conditions of force application, including the rate of change and geometry of the mechanical perturbation. Hence, using the GPU-based implementation of RNGs, presented here, in conjunction with Langevin simulations, makes it possible to directly compare the results of dynamic force measurements in vitro and in silico.

  5. Leveraging Random Number Generation for Mastery of Learning in Teaching Quantitative Research Courses via an E-Learning Method

    Science.gov (United States)

    Boonsathorn, Wasita; Charoen, Danuvasin; Dryver, Arthur L.

    2014-01-01

    E-Learning brings access to a powerful but often overlooked teaching tool: random number generation. Using random number generation, a practically infinite number of quantitative problem-solution sets can be created. In addition, within the e-learning context, in the spirit of the mastery of learning, it is possible to assign online quantitative…

  6. The cosmic microwave background radiation power spectrum as a random bit generator for symmetric- and asymmetric-key cryptography.

    Science.gov (United States)

    Lee, Jeffrey S; Cleaver, Gerald B

    2017-10-01

    In this note, the Cosmic Microwave Background (CMB) Radiation is shown to be capable of functioning as a Random Bit Generator, and constitutes an effectively infinite supply of truly random one-time pad values of arbitrary length. It is further argued that the CMB power spectrum potentially conforms to the FIPS 140-2 standard. Additionally, its applicability to the generation of a (n × n) random key matrix for a Vernam cipher is established.

  7. Structural variation discovery in the cancer genome using next generation sequencing: Computational solutions and perspectives

    Science.gov (United States)

    Liu, Biao; Conroy, Jeffrey M.; Morrison, Carl D.; Odunsi, Adekunle O.; Qin, Maochun; Wei, Lei; Trump, Donald L.; Johnson, Candace S.; Liu, Song; Wang, Jianmin

    2015-01-01

    Somatic Structural Variations (SVs) are a complex collection of chromosomal mutations that could directly contribute to carcinogenesis. Next Generation Sequencing (NGS) technology has emerged as the primary means of interrogating the SVs of the cancer genome in recent investigations. Sophisticated computational methods are required to accurately identify the SV events and delineate their breakpoints from the massive amounts of reads generated by a NGS experiment. In this review, we provide an overview of current analytic tools used for SV detection in NGS-based cancer studies. We summarize the features of common SV groups and the primary types of NGS signatures that can be used in SV detection methods. We discuss the principles and key similarities and differences of existing computational programs and comment on unresolved issues related to this research field. The aim of this article is to provide a practical guide of relevant concepts, computational methods, software tools and important factors for analyzing and interpreting NGS data for the detection of SVs in the cancer genome. PMID:25849937

  8. Unscheduled load flow effect due to large variation in the distributed generation in a subtransmission network

    Science.gov (United States)

    Islam, Mujahidul

    A sustainable energy delivery infrastructure implies the safe and reliable accommodation of large scale penetration of renewable sources in the power grid. In this dissertation it is assumed there will be no significant change in the power transmission and distribution structure currently in place; except in the operating strategy and regulatory policy. That is to say, with the same old structure, the path towards unveiling a high penetration of switching power converters in the power system will be challenging. Some of the dimensions of this challenge are power quality degradation, frequent false trips due to power system imbalance, and losses due to a large neutral current. The ultimate result is the reduced life of many power distribution components - transformers, switches and sophisticated loads. Numerous ancillary services are being developed and offered by the utility operators to mitigate these problems. These services will likely raise the system's operational cost, not only from the utility operators' end, but also reflected on the Independent System Operators and by the Regional Transmission Operators (RTO) due to an unforeseen backlash of frequent variation in the load-side generation or distributed generation. The North American transmission grid is an interconnected system similar to a large electrical circuit. This circuit was not planned but designed over 100 years. The natural laws of physics govern the power flow among loads and generators except where control mechanisms are installed. The control mechanism has not matured enough to withstand the high penetration of variable generators at uncontrolled distribution ends. Unlike a radial distribution system, mesh or loop networks can alleviate complex channels for real and reactive power flow. Significant variation in real power injection and absorption on the distribution side can emerge as a bias signal on the routing reactive power in some physical links or channels that are not distinguishable

  9. Application of random number generators in genetic algorithms to improve rainfall-runoff modelling

    Science.gov (United States)

    Chlumecký, Martin; Buchtele, Josef; Richta, Karel

    2017-10-01

    The efficient calibration of rainfall-runoff models is a difficult issue, even for experienced hydrologists. Therefore, fast and high-quality model calibration is a valuable improvement. This paper describes a novel methodology and software for the optimisation of a rainfall-runoff modelling using a genetic algorithm (GA) with a newly prepared concept of a random number generator (HRNG), which is the core of the optimisation. The GA estimates model parameters using evolutionary principles, which requires a quality number generator. The new HRNG generates random numbers based on hydrological information and it provides better numbers compared to pure software generators. The GA enhances the model calibration very well and the goal is to optimise the calibration of the model with a minimum of user interaction. This article focuses on improving the internal structure of the GA, which is shielded from the user. The results that we obtained indicate that the HRNG provides a stable trend in the output quality of the model, despite various configurations of the GA. In contrast to previous research, the HRNG speeds up the calibration of the model and offers an improvement of rainfall-runoff modelling.

  10. Engineering applications of fpgas chaotic systems, artificial neural networks, random number generators, and secure communication systems

    CERN Document Server

    Tlelo-Cuautle, Esteban; de la Fraga, Luis Gerardo

    2016-01-01

    This book offers readers a clear guide to implementing engineering applications with FPGAs, from the mathematical description to the hardware synthesis, including discussion of VHDL programming and co-simulation issues. Coverage includes FPGA realizations such as: chaos generators that are described from their mathematical models; artificial neural networks (ANNs) to predict chaotic time series, for which a discussion of different ANN topologies is included, with different learning techniques and activation functions; random number generators (RNGs) that are realized using different chaos generators, and discussions of their maximum Lyapunov exponent values and entropies. Finally, optimized chaotic oscillators are synchronized and realized to implement a secure communication system that processes black and white and grey-scale images. In each application, readers will find VHDL programming guidelines and computer arithmetic issues, along with co-simulation examples with Active-HDL and Simulink. Readers will b...

  11. Reproductive Fitness and Random Amplified Polymorphic DNA Variation among Isolates of Pratylenchus vulnus.

    Science.gov (United States)

    Pinochet, P; Cenis, J L; Fernández, C; Doucet, M; Maruli, J

    1994-09-01

    The reproductive fitness of seven isolates of Pratylenchus vulnus from different geographical areas and hosts was assessed in monoxenic cultures (carrot), and greenhouse cultures (plum, sour orange, and quince). The genetic makeup of the different isolates was compared by Random Amplified Polymorphic DNA (RAPD-PCR). The apple (PvAP-S) and apricot (PvAT-F) isolates reproduced less in monoxenic cultures than the rose (PvRO-S) and walnut (PvWA-A and PvWA-U) isolates. On plum, the rose isolate (PvRO-S) reproduced better than the apple (PvAP-S) and walnut isolate from the United States (PvWA-U). On sour orange, the apple (PvAP-S), unknown origin (PvU-UK), and walnut isolate from Argentina (PvWA-A) multiplied well, whereas the walnut isolate from the United States (PvWA-U), apricot (PvAT-F), and rose (PvRO-S) did not. On quince, the apple (PvAP-S) and walnut (PvWA-U) isolates showed a higher reproduction than the one from unknown origin (PvU-UK). RAPD-PCR patterns among the seven P. vulnus isolates were similar, although high intraspecific varibility was detected. Very few bands of P. neglectus were shared by any population of P. vulnus. A high degree of similarity was found among the patterns corresponding to the rose (PvRO-S), apple (PvAP-S), walnut from the United States (PvWA-U), and unknown origin (PvUK-U) isolates. The apricot isolate (PvAT-F) was the most dissimilar among the seven isolates. No correlation could be established between the genetic variation of P. vulnus detected by RAPD-PCR and reproductive fitness. Results demonstrate high genetic varibility between geographically separated populations of P. vulnus.

  12. Variation in motor output and motor performance in a centrally generated motor pattern.

    Science.gov (United States)

    Wenning, Angela; Norris, Brian J; Doloc-Mihu, Anca; Calabrese, Ronald L

    2014-07-01

    Central pattern generators (CPGs) produce motor patterns that ultimately drive motor outputs. We studied how functional motor performance is achieved, specifically, whether the variation seen in motor patterns is reflected in motor performance and whether fictive motor patterns differ from those in vivo. We used the leech heartbeat system in which a bilaterally symmetrical CPG coordinates segmental heart motor neurons and two segmented heart tubes into two mutually exclusive coordination modes: rear-to-front peristaltic on one side and nearly synchronous on the other, with regular side-to-side switches. We assessed individual variability of the motor pattern and the beat pattern in vivo. To quantify the beat pattern we imaged intact adults. To quantify the phase relations between motor neurons and heart constrictions we recorded extracellularly from two heart motor neurons and movement from the corresponding heart segments in minimally dissected leeches. Variation in the motor pattern was reflected in motor performance only in the peristaltic mode, where larger intersegmental phase differences in the motor neurons resulted in larger phase differences between heart constrictions. Fictive motor patterns differed from those in vivo only in the synchronous mode, where intersegmental phase differences in vivo had a larger front-to-rear bias and were more constrained. Additionally, load-influenced constriction timing might explain the amplification of the phase differences between heart segments in the peristaltic mode and the higher variability in motor output due to body shape assumed in this soft-bodied animal. The motor pattern determines the beat pattern, peristaltic or synchronous, but heart mechanics influence the phase relations achieved. Copyright © 2014 the American Physiological Society.

  13. Thermodynamic method for generating random stress distributions on an earthquake fault

    Science.gov (United States)

    Barall, Michael; Harris, Ruth A.

    2012-01-01

    This report presents a new method for generating random stress distributions on an earthquake fault, suitable for use as initial conditions in a dynamic rupture simulation. The method employs concepts from thermodynamics and statistical mechanics. A pattern of fault slip is considered to be analogous to a micro-state of a thermodynamic system. The energy of the micro-state is taken to be the elastic energy stored in the surrounding medium. Then, the Boltzmann distribution gives the probability of a given pattern of fault slip and stress. We show how to decompose the system into independent degrees of freedom, which makes it computationally feasible to select a random state. However, due to the equipartition theorem, straightforward application of the Boltzmann distribution leads to a divergence which predicts infinite stress. To avoid equipartition, we show that the finite strength of the fault acts to restrict the possible states of the system. By analyzing a set of earthquake scaling relations, we derive a new formula for the expected power spectral density of the stress distribution, which allows us to construct a computer algorithm free of infinities. We then present a new technique for controlling the extent of the rupture by generating a random stress distribution thousands of times larger than the fault surface, and selecting a portion which, by chance, has a positive stress perturbation of the desired size. Finally, we present a new two-stage nucleation method that combines a small zone of forced rupture with a larger zone of reduced fracture energy.

  14. Using Next-Generation Sequencing for DNA Barcoding: Capturing Allelic Variation in ITS2.

    Science.gov (United States)

    Batovska, Jana; Cogan, Noel O I; Lynch, Stacey E; Blacket, Mark J

    2017-01-05

    Internal Transcribed Spacer 2 (ITS2) is a popular DNA barcoding marker; however, in some animal species it is hypervariable and therefore difficult to sequence with traditional methods. With next-generation sequencing (NGS) it is possible to sequence all gene variants despite the presence of single nucleotide polymorphisms (SNPs), insertions/deletions (indels), homopolymeric regions, and microsatellites. Our aim was to compare the performance of Sanger sequencing and NGS amplicon sequencing in characterizing ITS2 in 26 mosquito species represented by 88 samples. The suitability of ITS2 as a DNA barcoding marker for mosquitoes, and its allelic diversity in individuals and species, was also assessed. Compared to Sanger sequencing, NGS was able to characterize the ITS2 region to a greater extent, with resolution within and between individuals and species that was previously not possible. A total of 382 unique sequences (alleles) were generated from the 88 mosquito specimens, demonstrating the diversity present that has been overlooked by traditional sequencing methods. Multiple indels and microsatellites were present in the ITS2 alleles, which were often specific to species or genera, causing variation in sequence length. As a barcoding marker, ITS2 was able to separate all of the species, apart from members of the Culex pipiens complex, providing the same resolution as the commonly used Cytochrome Oxidase I (COI). The ability to cost-effectively sequence hypervariable markers makes NGS an invaluable tool with many applications in the DNA barcoding field, and provides insights into the limitations of previous studies and techniques. Copyright © 2017 Batovska et al.

  15. Using Next-Generation Sequencing for DNA Barcoding: Capturing Allelic Variation in ITS2

    Directory of Open Access Journals (Sweden)

    Jana Batovska

    2017-01-01

    Full Text Available Internal Transcribed Spacer 2 (ITS2 is a popular DNA barcoding marker; however, in some animal species it is hypervariable and therefore difficult to sequence with traditional methods. With next-generation sequencing (NGS it is possible to sequence all gene variants despite the presence of single nucleotide polymorphisms (SNPs, insertions/deletions (indels, homopolymeric regions, and microsatellites. Our aim was to compare the performance of Sanger sequencing and NGS amplicon sequencing in characterizing ITS2 in 26 mosquito species represented by 88 samples. The suitability of ITS2 as a DNA barcoding marker for mosquitoes, and its allelic diversity in individuals and species, was also assessed. Compared to Sanger sequencing, NGS was able to characterize the ITS2 region to a greater extent, with resolution within and between individuals and species that was previously not possible. A total of 382 unique sequences (alleles were generated from the 88 mosquito specimens, demonstrating the diversity present that has been overlooked by traditional sequencing methods. Multiple indels and microsatellites were present in the ITS2 alleles, which were often specific to species or genera, causing variation in sequence length. As a barcoding marker, ITS2 was able to separate all of the species, apart from members of the Culex pipiens complex, providing the same resolution as the commonly used Cytochrome Oxidase I (COI. The ability to cost-effectively sequence hypervariable markers makes NGS an invaluable tool with many applications in the DNA barcoding field, and provides insights into the limitations of previous studies and techniques.

  16. rMotifGen: random motif generator for DNA and protein sequences

    Directory of Open Access Journals (Sweden)

    Hardin C Timothy

    2007-08-01

    Full Text Available Abstract Background Detection of short, subtle conserved motif regions within a set of related DNA or amino acid sequences can lead to discoveries about important regulatory domains such as transcription factor and DNA binding sites as well as conserved protein domains. In order to help assess motif detection algorithms on motifs with varying properties and levels of conservation, we have developed a computational tool, rMotifGen, with the sole purpose of generating a number of random DNA or protein sequences containing short sequence motifs. Each motif consensus can be user-defined, randomly generated, or created from a position-specific scoring matrix (PSSM. Insertions and mutations within these motifs are created according to user-defined parameters and substitution matrices. The resulting sequences can be helpful in mutational simulations and in testing the limits of motif detection algorithms. Results Two implementations of rMotifGen have been created, one providing a graphical user interface (GUI for random motif construction, and the other serving as a command line interface. The second implementation has the added advantages of platform independence and being able to be called in a batch mode. rMotifGen was used to construct sample sets of sequences containing DNA motifs and amino acid motifs that were then tested against the Gibbs sampler and MEME packages. Conclusion rMotifGen provides an efficient and convenient method for creating random DNA or amino acid sequences with a variable number of motifs, where the instance of each motif can be incorporated using a position-specific scoring matrix (PSSM or by creating an instance mutated from its corresponding consensus using an evolutionary model based on substitution matrices. rMotifGen is freely available at: http://bioinformatics.louisville.edu/brg/rMotifGen/.

  17. Human Y chromosome copy number variation in the next generation sequencing era and beyond.

    Science.gov (United States)

    Massaia, Andrea; Xue, Yali

    2017-05-01

    The human Y chromosome provides a fertile ground for structural rearrangements owing to its haploidy and high content of repeated sequences. The methodologies used for copy number variation (CNV) studies have developed over the years. Low-throughput techniques based on direct observation of rearrangements were developed early on, and are still used, often to complement array-based or sequencing approaches which have limited power in regions with high repeat content and specifically in the presence of long, identical repeats, such as those found in human sex chromosomes. Some specific rearrangements have been investigated for decades; because of their effects on fertility, or their outstanding evolutionary features, the interest in these has not diminished. However, following the flourishing of large-scale genomics, several studies have investigated CNVs across the whole chromosome. These studies sometimes employ data generated within large genomic projects such as the DDD study or the 1000 Genomes Project, and often survey large samples of healthy individuals without any prior selection. Novel technologies based on sequencing long molecules and combinations of technologies, promise to stimulate the study of Y-CNVs in the immediate future.

  18. Total variation-based method for generation of intravoxel incoherent motion parametric images in MRI.

    Science.gov (United States)

    Lin, Chieh; Shih, Yi-Yu; Huang, Siao-Lan; Huang, Hsuan-Ming

    2017-10-01

    Total variation (TV) method has been used widely for image restoration and reconstruction. In this work, we propose a TV-based algorithm for parametric image generation in intravoxel incoherent motion (IVIM) diffusion-weighted magnetic resonance imaging (DW-MRI). We used simulated and real data to investigate whether the proposed TV-based method can provide reliable parametric images. Parametric images of IVIM parameters including perfusion fraction (PF), diffusion coefficient (D), and pseudo-diffusion coefficient (D*) were estimated using DW-MRI data and TV through fitting the IVIM model. The Levenberg-Marquardt (LM) method, which has often been used in the context of IVIM analysis, was employed as the standard method for comparison of the resulting parametric images. The simulation results show that the proposed method outperforms the LM algorithm in terms of precision, providing a 40-81%, 90-93%, and 68-84% improvement for PF, D and D*, respectively, at signal-to-noise ratio (SNR) of 30. For real data, the proposed method showed an average five-fold, three-fold, and four-fold improvement in the SNR for PF, D and D*, respectively. We introduced the use of TV to produce parametric images, and demonstrated that the proposed TV-based method is effective in improving the parametric image quality. Magn Reson Med 78:1383-1391, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  19. Model and scenario variations in predicted number of generations of Spodoptera litura Fab. on peanut during future climate change scenario.

    Science.gov (United States)

    Rao, Mathukumalli Srinivasa; Swathi, Pettem; Rao, Chitiprolu Anantha Rama; Rao, K V; Raju, B M K; Srinivas, Karlapudi; Manimanjari, Dammu; Maheswari, Mandapaka

    2015-01-01

    The present study features the estimation of number of generations of tobacco caterpillar, Spodoptera litura. Fab. on peanut crop at six locations in India using MarkSim, which provides General Circulation Model (GCM) of future data on daily maximum (T.max), minimum (T.min) air temperatures from six models viz., BCCR-BCM2.0, CNRM-CM3, CSIRO-Mk3.5, ECHams5, INCM-CM3.0 and MIROC3.2 along with an ensemble of the six from three emission scenarios (A2, A1B and B1). This data was used to predict the future pest scenarios following the growing degree days approach in four different climate periods viz., Baseline-1975, Near future (NF) -2020, Distant future (DF)-2050 and Very Distant future (VDF)-2080. It is predicted that more generations would occur during the three future climate periods with significant variation among scenarios and models. Among the seven models, 1-2 additional generations were predicted during DF and VDF due to higher future temperatures in CNRM-CM3, ECHams5 & CSIRO-Mk3.5 models. The temperature projections of these models indicated that the generation time would decrease by 18-22% over baseline. Analysis of variance (ANOVA) was used to partition the variation in the predicted number of generations and generation time of S. litura on peanut during crop season. Geographical location explained 34% of the total variation in number of generations, followed by time period (26%), model (1.74%) and scenario (0.74%). The remaining 14% of the variation was explained by interactions. Increased number of generations and reduction of generation time across the six peanut growing locations of India suggest that the incidence of S. litura may increase due to projected increase in temperatures in future climate change periods.

  20. Model and scenario variations in predicted number of generations of Spodoptera litura Fab. on peanut during future climate change scenario.

    Directory of Open Access Journals (Sweden)

    Mathukumalli Srinivasa Rao

    Full Text Available The present study features the estimation of number of generations of tobacco caterpillar, Spodoptera litura. Fab. on peanut crop at six locations in India using MarkSim, which provides General Circulation Model (GCM of future data on daily maximum (T.max, minimum (T.min air temperatures from six models viz., BCCR-BCM2.0, CNRM-CM3, CSIRO-Mk3.5, ECHams5, INCM-CM3.0 and MIROC3.2 along with an ensemble of the six from three emission scenarios (A2, A1B and B1. This data was used to predict the future pest scenarios following the growing degree days approach in four different climate periods viz., Baseline-1975, Near future (NF -2020, Distant future (DF-2050 and Very Distant future (VDF-2080. It is predicted that more generations would occur during the three future climate periods with significant variation among scenarios and models. Among the seven models, 1-2 additional generations were predicted during DF and VDF due to higher future temperatures in CNRM-CM3, ECHams5 & CSIRO-Mk3.5 models. The temperature projections of these models indicated that the generation time would decrease by 18-22% over baseline. Analysis of variance (ANOVA was used to partition the variation in the predicted number of generations and generation time of S. litura on peanut during crop season. Geographical location explained 34% of the total variation in number of generations, followed by time period (26%, model (1.74% and scenario (0.74%. The remaining 14% of the variation was explained by interactions. Increased number of generations and reduction of generation time across the six peanut growing locations of India suggest that the incidence of S. litura may increase due to projected increase in temperatures in future climate change periods.

  1. Analytical and between-subject variation of thrombin generation measured by calibrated automated thrombography on plasma samples.

    Science.gov (United States)

    Kristensen, Anne F; Kristensen, Søren R; Falkmer, Ursula; Münster, Anna-Marie B; Pedersen, Shona

    2018-01-16

    The Calibrated Automated Thrombography (CAT) is an in vitro thrombin generation (TG) assay that holds promise as a valuable tool within clinical diagnostics. However, the technique has a considerable analytical variation, and we therefore, investigated the analytical and between-subject variation of CAT systematically. Moreover, we assess the application of an internal standard for normalization to diminish variation. 20 healthy volunteers donated one blood sample which was subsequently centrifuged, aliquoted and stored at -80 °C prior to analysis. The analytical variation was determined on eight runs, where plasma from the same seven volunteers was processed in triplicates, and for the between-subject variation, TG analysis was performed on plasma from all 20 volunteers. The trigger reagents used for the TG assays included both PPP reagent containing 5 pM tissue factor (TF) and PPPlow with 1 pM TF. Plasma, drawn from a single donor, was applied to all plates as an internal standard for each TG analysis, which subsequently was used for normalization. The total analytical variation for TG analysis performed with PPPlow reagent is 3-14% and 9-13% for PPP reagent. This variation can be minimally reduced by using an internal standard but mainly for ETP (endogenous thrombin potential). The between-subject variation is higher when using PPPlow than PPP and this variation is considerable higher than the analytical variation. TG has a rather high inherent analytical variation but considerable lower than the between-subject variation when using PPPlow as reagent.

  2. Emergence of deterministic Green's functions from noise generated by finite random sources.

    Science.gov (United States)

    Godin, Oleg A

    2009-12-01

    Two-point correlation functions of sufficiently diffuse wave fields generated by uncorrelated random sources are known to approximate deterministic Green's functions between the two points. This property is utilized increasingly for passive imaging and remote sensing of the environment. Here we show that the relation between the Green's functions and the noise cross-correlation function holds under much less restrictive conditions than previously thought. It can even hold when ambient noise sources have correlation ranges large compared to the wavelength. Admissible correlation ranges are limited from above by the size of the Fresnel zone at wave propagation between the points where noise cross correlation is evaluated.

  3. Random number generator based on an integrated laser with on-chip optical feedback

    Science.gov (United States)

    Verschaffelt, Guy; Khoder, Mulham; Van der Sande, Guy

    2017-11-01

    We discuss the design and testing of a laser integrated with a long on-chip optical feedback section. The device and feedback section have been fabricated on a generic photonic integration platform using only standard building blocks. We have been able to integrate a 10 cm feedback length on a footprint of 5.5 mm2. By controlling the amount of feedback, we achieve chaotic dynamics in the long-cavity regime and show that the resulting dynamics is sufficiently complex in order to generate random bits based on the chaotic intensity fluctuation at a rate of 500 Mbits/s.

  4. Application of random number generators in genetic algorithms to improve rainfall-runoff modelling

    Czech Academy of Sciences Publication Activity Database

    Chlumecký, M.; Buchtele, Josef; Richta, K.

    2017-01-01

    Roč. 553, October (2017), s. 350-355 ISSN 0022-1694 Institutional support: RVO:67985874 Keywords : genetic algorithm * optimisation * rainfall-runoff modeling * random generator Subject RIV: DA - Hydrology ; Limnology Impact factor: 3.483, year: 2016 https://ac.els-cdn.com/S0022169417305516/1-s2.0-S0022169417305516-main.pdf?_tid=fa1bad8a-bd6a-11e7-8567-00000aab0f27&acdnat=1509365462_a1335d3d997e9eab19e23b1eee977705

  5. On Generating Optimal Signal Probabilities for Random Tests: A Genetic Approach

    Directory of Open Access Journals (Sweden)

    M. Srinivas

    1996-01-01

    Full Text Available Genetic Algorithms are robust search and optimization techniques. A Genetic Algorithm based approach for determining the optimal input distributions for generating random test vectors is proposed in the paper. A cost function based on the COP testability measure for determining the efficacy of the input distributions is discussed. A brief overview of Genetic Algorithms (GAs and the specific details of our implementation are described. Experimental results based on ISCAS-85 benchmark circuits are presented. The performance of our GAbased approach is compared with previous results. While the GA generates more efficient input distributions than the previous methods which are based on gradient descent search, the overheads of the GA in computing the input distributions are larger.

  6. A Chemical Reaction Network to Generate Random, Power-Law-Distributed Time Intervals.

    Science.gov (United States)

    Krauss, Patrick; Schulze, Holger; Metzner, Claus

    2017-10-06

    In Lévy walks (LWs), particles move with a fixed speed along straight line segments and turn in new directions after random time intervals that are distributed according to a power law. Such LWs are thought to be an advantageous foraging and search strategy for organisms. While complex nervous systems are certainly capable of producing such behavior, it is not clear at present how single-cell organisms can generate the long-term correlated control signals required for a LW. Here, we construct a biochemical reaction system that generates long-time correlated concentration fluctuations of a signaling substance, with a tunable fractional exponent of the autocorrelation function. The network is based on well-known modules, and its basic function is highly robust with respect to the parameter settings.

  7. A Hardware Efficient Random Number Generator for Nonuniform Distributions with Arbitrary Precision

    Directory of Open Access Journals (Sweden)

    Christian de Schryver

    2012-01-01

    number generators is a very active research field. However, most state-of-the-art architectures are either tailored to specific distributions or use up a lot of hardware resources. At ReConFig 2010, we have presented a new design that saves up to 48% of area compared to state-of-the-art inversion-based implementation, usable for arbitrary distributions and precision. In this paper, we introduce a more flexible version together with a refined segmentation scheme that allows to further reduce the approximation error significantly. We provide a free software tool allowing users to implement their own distributions easily, and we have tested our random number generator thoroughly by statistic analysis and two application tests.

  8. Racial variation in treatment preferences and willingness to randomize in the Spine Patient Outcomes Research Trial (SPORT).

    Science.gov (United States)

    Arega, Addisalem; Birkmeyer, Nancy J O; Lurie, Jon D N; Tosteson, Tor; Gibson, Jennifer; Taylor, Brett A; Morgan, Tamara Shawver; Weinstein, James N

    2006-09-01

    Analysis of baseline data for patients enrolled in Spine Patient Outcomes Research Trial (SPORT), a project conducting three randomized and three observational cohort studies of surgical and nonoperative treatments for intervertebral disc herniation (IDH), spinal stenosis (SpS), and degenerative spondylolisthesis (DS). To explore racial variation in treatment preferences and willingness to be randomized. Increasing minority participation in research has been a priority at the NIH. Prior studies have documented lower rates of participation in research and preferences for invasive treatment among African-Americans. Patients enrolled in SPORT (March 2000 to February 2005) that reported data on their race (n = 2,323) were classified as White (87%), Black (8%), or Other (5%). Treatment preferences (nonoperative, unsure, surgical), and willingness to be randomized were compared among these groups while controlling for baseline differences using multivariate logistic regression. RESULTS.: There were numerous significant differences in baseline characteristics among the racial groups. Following adjustment for these differences, Blacks remained less likely to prefer surgical treatment among both IDH (White, 55%; Black, 37%; Other, 55%, P = 0.023) and SpS/DS (White, 46%; Black, 30%; Other, 43%; P = 0.017) patients. Higher randomization rates among Black IDH patients (46% vs. 30%) were no longer significant following adjustment (odds ratio [OR] = 1.45, P = 0.235). Treatment preference remained a strong independent predictor of randomization in multivariate analyses for both IDH (unsure OR = 3.88, P race and willingness to be randomized.

  9. Generation mechanism of nonlinear ultrasonic Lamb waves in thin plates with randomly distributed micro-cracks.

    Science.gov (United States)

    Zhao, Youxuan; Li, Feilong; Cao, Peng; Liu, Yaolu; Zhang, Jianyu; Fu, Shaoyun; Zhang, Jun; Hu, Ning

    2017-08-01

    Since the identification of micro-cracks in engineering materials is very valuable in understanding the initial and slight changes in mechanical properties of materials under complex working environments, numerical simulations on the propagation of the low frequency S 0 Lamb wave in thin plates with randomly distributed micro-cracks were performed to study the behavior of nonlinear Lamb waves. The results showed that while the influence of the randomly distributed micro-cracks on the phase velocity of the low frequency S 0 fundamental waves could be neglected, significant ultrasonic nonlinear effects caused by the randomly distributed micro-cracks was discovered, which mainly presented as a second harmonic generation. By using a Monte Carlo simulation method, we found that the acoustic nonlinear parameter increased linearly with the micro-crack density and the size of micro-crack zone, and it was also related to the excitation frequency and friction coefficient of the micro-crack surfaces. In addition, it was found that the nonlinear effect of waves reflected by the micro-cracks was more noticeable than that of the transmitted waves. This study theoretically reveals that the low frequency S 0 mode of Lamb waves can be used as the fundamental waves to quantitatively identify micro-cracks in thin plates. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. 1.2 GBit/s Pseudo Random Pulse Generator Using Multiplexing with GaAs Mesfet Gates

    DEFF Research Database (Denmark)

    Hede, Carsten

    1978-01-01

    A l.2 Gbit/s RZ pseudo random bit generator using multiplexing of six 200 Mbit/s channels, and a GaAs-MESFET gate circuit which exhibits both high speed and simplicity are presented. As a new contribution to the treatment of pseudo random sequences it is shown how the autocorrelation function and...

  11. Generation of Variations on Theme Music Based on Impressions of Story Scenes Considering Human's Feeling of Music and Stories

    Directory of Open Access Journals (Sweden)

    Kenkichi Ishizuka

    2008-01-01

    Full Text Available This paper describes a system which generates variations on theme music fitting to story scenes represented by texts and/or pictures. Inputs to the present system are original theme music and numerical information on given story scenes. The present system varies melodies, tempos, tones, tonalities, and accompaniments of given theme music based on impressions of story scenes. Genetic algorithms (GAs using modular neural network (MNN models as fitness functions are applied to music generation in order to reflect user's feeling of music and stories. The present system adjusts MNN models for each user on line. This paper also describes the evaluation experiments to confirm whether the generated variations on theme music reflect impressions of story scenes appropriately or not.

  12. The cosmic microwave background radiation power spectrum as a random bit generator for symmetric- and asymmetric-key cryptography

    Directory of Open Access Journals (Sweden)

    Jeffrey S. Lee

    2017-10-01

    Full Text Available In this note, the Cosmic Microwave Background (CMB Radiation is shown to be capable of functioning as a Random Bit Generator, and constitutes an effectively infinite supply of truly random one-time pad values of arbitrary length. It is further argued that the CMB power spectrum potentially conforms to the FIPS 140-2 standard. Additionally, its applicability to the generation of a (n × n random key matrix for a Vernam cipher is established. Keywords: Particle physics, Computer science, Mathematics, Astrophysics

  13. Harvesting Entropy for Random Number Generation for Internet of Things Constrained Devices Using On-Board Sensors

    Science.gov (United States)

    Pawlowski, Marcin Piotr; Jara, Antonio; Ogorzalek, Maciej

    2015-01-01

    Entropy in computer security is associated with the unpredictability of a source of randomness. The random source with high entropy tends to achieve a uniform distribution of random values. Random number generators are one of the most important building blocks of cryptosystems. In constrained devices of the Internet of Things ecosystem, high entropy random number generators are hard to achieve due to hardware limitations. For the purpose of the random number generation in constrained devices, this work proposes a solution based on the least-significant bits concatenation entropy harvesting method. As a potential source of entropy, on-board integrated sensors (i.e., temperature, humidity and two different light sensors) have been analyzed. Additionally, the costs (i.e., time and memory consumption) of the presented approach have been measured. The results obtained from the proposed method with statistical fine tuning achieved a Shannon entropy of around 7.9 bits per byte of data for temperature and humidity sensors. The results showed that sensor-based random number generators are a valuable source of entropy with very small RAM and Flash memory requirements for constrained devices of the Internet of Things. PMID:26506357

  14. Harvesting entropy for random number generation for internet of things constrained devices using on-board sensors.

    Science.gov (United States)

    Pawlowski, Marcin Piotr; Jara, Antonio; Ogorzalek, Maciej

    2015-10-22

    Entropy in computer security is associated with the unpredictability of a source of randomness. The random source with high entropy tends to achieve a uniform distribution of random values. Random number generators are one of the most important building blocks of cryptosystems. In constrained devices of the Internet of Things ecosystem, high entropy random number generators are hard to achieve due to hardware limitations. For the purpose of the random number generation in constrained devices, this work proposes a solution based on the least-significant bits concatenation entropy harvesting method. As a potential source of entropy, on-board integrated sensors (i.e., temperature, humidity and two different light sensors) have been analyzed. Additionally, the costs (i.e., time and memory consumption) of the presented approach have been measured. The results obtained from the proposed method with statistical fine tuning achieved a Shannon entropy of around 7.9 bits per byte of data for temperature and humidity sensors. The results showed that sensor-based random number generators are a valuable source of entropy with very small RAM and Flash memory requirements for constrained devices of the Internet of Things.

  15. Harvesting Entropy for Random Number Generation for Internet of Things Constrained Devices Using On-Board Sensors

    Directory of Open Access Journals (Sweden)

    Marcin Piotr Pawlowski

    2015-10-01

    Full Text Available Entropy in computer security is associated with the unpredictability of a source of randomness. The random source with high entropy tends to achieve a uniform distribution of random values. Random number generators are one of the most important building blocks of cryptosystems. In constrained devices of the Internet of Things ecosystem, high entropy random number generators are hard to achieve due to hardware limitations. For the purpose of the random number generation in constrained devices, this work proposes a solution based on the least-significant bits concatenation entropy harvesting method. As a potential source of entropy, on-board integrated sensors (i.e., temperature, humidity and two different light sensors have been analyzed. Additionally, the costs (i.e., time and memory consumption of the presented approach have been measured. The results obtained from the proposed method with statistical fine tuning achieved a Shannon entropy of around 7.9 bits per byte of data for temperature and humidity sensors. The results showed that sensor-based random number generators are a valuable source of entropy with very small RAM and Flash memory requirements for constrained devices of the Internet of Things.

  16. Total variation regularization of the 3-D gravity inverse problem using a randomized generalized singular value decomposition

    Science.gov (United States)

    Vatankhah, Saeed; Renaut, Rosemary A.; Ardestani, Vahid E.

    2018-01-01

    We present a fast algorithm for the total variation regularization of the 3-D gravity inverse problem. Through imposition of the total variation regularization, subsurface structures presenting with sharp discontinuities are preserved better than when using a conventional minimum-structure inversion. The associated problem formulation for the regularization is non linear but can be solved using an iteratively reweighted least squares algorithm. For small scale problems the regularized least squares problem at each iteration can be solved using the generalized singular value decomposition. This is not feasible for large, or even moderate, scale problems. Instead we introduce the use of a randomized generalized singular value decomposition in order to reduce the dimensions of the problem and provide an effective and efficient solution technique. For further efficiency an alternating direction algorithm is used to implement the total variation weighting operator within the iteratively reweighted least squares algorithm. Presented results for synthetic examples demonstrate that the novel randomized decomposition provides good accuracy for reduced computational and memory demands as compared to use of classical approaches.

  17. Optical key distribution system using atmospheric turbulence as the randomness generating function: classical optical protocol for information assurance

    Science.gov (United States)

    Drake, Marvin D.; Bas, Christophe F.; Gervais, David; Renda, Priscilla F.; Townsend, Daniel; Rushanan, Joseph J.; Francoeur, Joe; Donnangelo, Nick; Stenner, Michael D.

    2013-05-01

    We describe an experimental laboratory system that generates and distributes random binary sequence bit streams between two optical terminals (labeled Alice and Bob). The random binary sequence is generated through probing the optical channel of a turbulent atmosphere between the two terminals with coincident laser beams. The two laser beams experience differential phase delays while propagating through the atmospheric optical channel. The differential phase delays are detected and sampled at each terminal to yield raw random bit streams. The random bit streams are processed to remove bit errors and, through privacy amplification, to yield a bit stream known only to Alice and Bob. The same chaotic physical mechanism that provides randomness also provides confidentiality. The laboratory system yielded secret key bit rates of a few bits/second. For external optical channels over longer channel lengths with atmospheric turbulence levels, secret bit rates of 10 s of bits/second are predicted.

  18. Variations on a theme: species differences in synaptic connectivity do not predict central pattern generator activity.

    Science.gov (United States)

    Gunaratne, Charuni A; Sakurai, Akira; Katz, Paul S

    2017-08-01

    A fundamental question in comparative neuroethology is the extent to which synaptic wiring determines behavior vs. the extent to which it is constrained by phylogeny. We investigated this by examining the connectivity and activity of homologous neurons in different species. Melibe leonina and Dendronotus iris (Mollusca, Gastropoda, Nudibranchia) have homologous neurons and exhibit homologous swimming behaviors consisting of alternating left-right (LR) whole body flexions. Yet, a homologous interneuron (Si1) differs between the two species in its participation in the swim motor pattern (SMP) and synaptic connectivity. In this study we examined Si1 homologs in two additional nudibranchs: Flabellina iodinea , which evolved LR swimming independently of Melibe and Dendronotus , and Tritonia diomedea , which swims with dorsal-ventral (DV) body flexions. In Flabellina , the contralateral Si1s exhibit alternating rhythmic bursting activity during the SMP and are members of the swim central pattern generator (CPG), as in Melibe The Si1 homologs in Tritonia do not burst rhythmically during the DV SMP but are inhibited and receive bilaterally synchronous synaptic input. In both Flabellina and Tritonia , the Si1 homologs exhibit reciprocal inhibition, as in Melibe However, in Flabellina the inhibition is polysynaptic, whereas in Tritonia it is monosynaptic, as in Melibe In all species, the contralateral Si1s are electrically coupled. These results suggest that Flabellina and Melibe convergently evolved a swim CPG that contains Si1; however, they differ in monosynaptic connections. Connectivity is more similar between Tritonia and Melibe , which exhibit different swimming behaviors. Thus connectivity between homologous neurons varies independently of both behavior and phylogeny. NEW & NOTEWORTHY This research shows that the synaptic connectivity between homologous neurons exhibits species-specific variations on a basic theme. The neurons vary in the extent of electrical

  19. Simple variational ground state and pure-cat-state generation in the quantum Rabi model

    Science.gov (United States)

    Leroux, C.; Govia, L. C. G.; Clerk, A. A.

    2017-10-01

    We introduce a simple, physically motivated variational ground state for the quantum Rabi model and demonstrate that it provides a high-fidelity approximation of the true ground state in all parameter regimes (including intermediate- and strong-coupling regimes). Our variational state is constructed using Gaussian cavity states and nonorthogonal qubit pointer states and contains only three variational parameters. We use our state to develop a heuristic understanding of how the ground state evolves with increasing coupling and find a parameter regime where the ground state corresponds to the cavity being in a nearly pure Schrödinger cat state.

  20. Reduced peak, but no diurnal variation, in thrombin generation upon melatonin supplementation in tetraplegia. A randomised, placebo-controlled study.

    Science.gov (United States)

    Iversen, Per Ole; Dahm, Anders; Skretting, Grethe; Mowinckel, Marie-Christine; Stranda, Annicke; Østerud, Bjarne; Sandset, Per Morten; Kostovski, Emil

    2015-11-01

    Tetraplegic patients have increased risk of venous thrombosis despite anti-thrombotic prophylaxis. Moreover, they have blunted plasma variations in melatonin and altered diurnal variation of several haemostatic markers, compared with able-bodied. However, whether healthy individuals and tetraplegic patients, with or without melatonin, display abnormalities in thrombin generation during a 24-hour (h) cycle, is unknown. We therefore used the Calibrated Automated Thrombogram (CAT) assay to examine diurnal variations and the possible role of melatonin in thrombin generation. Six men with long-standing complete tetraplegia were included in a randomised placebo-controlled cross-over study with melatonin supplementation (2 mg, 4 consecutive nights), whereas six healthy, able-bodied men served as controls. Ten plasma samples were collected frequently during a 24-h awake/sleep cycle. No significant diurnal variation of any of the measured CAT indices was detected in the three study groups. Whereas endogenous thrombin potential (ETP) was independent (p > 0.05) of whether the tetraplegic men received melatonin or placebo, melatonin decreased (p = 0.005) peak values in tetraplegia compared with those given placebo. Able-bodied men had lower (p = 0.019) ETP and Lag-Time (p = 0.018) compared with tetraplegics receiving placebo. Neither the Time-to-Peak nor the Start-Tail was affected (p > 0.05) by melatonin in tetraplegia. In conclusion, indices of thrombin generation are not subjected to diurnal variation in healthy able-bodied or tetraplegia, but peak thrombin generation is reduced in tetraplegic men receiving oral melatonin.

  1. An advanced monolithic digitalized random carrier frequency spread-spectrum clock generator for EMI suppression

    Energy Technology Data Exchange (ETDEWEB)

    Guo Haiyan; Chen Zao; Zhang Bo; Li Zhaoji, E-mail: guohy5@sina.co [State Key Laboratory of Electronic Thin Films and Integrated devices, University of Electronic Science and Technology of China, Chengdu 610054 (China)

    2010-06-15

    A novel monolithic digitalized random carrier frequency modulation spread-spectrum clock generator (RCF-SSCG) is proposed. In this design, the output frequency of the proposed RCF-SSCG changes with the intensity of the capacitive charge and discharge current. Its analytical model is induced and the effect of the modulation parameters on the spread spectrum is numerically simulated and discussed. Compared with other works, this design has the advantages of small size, low power consumption and good robustness. The circuit has been fabricated in a 0.5 {mu}m CMOS process and applied to a class D amplifier in which the proposed RCF-SSCG occupies an area of 0.112 mm{sup 2} and consumes 9 mW. The experimental results confirm the theoretical analyses. (semiconductor integrated circuits)

  2. Engineering practice variation through provider agreement: a cluster-randomized feasibility trial

    OpenAIRE

    McCarren M; Twedt EL; Mansuri FM; Nelson PR; Peek BT

    2014-01-01

    Madeline McCarren,1 Elaine L Twedt,1 Faizmohamed M Mansuri,2 Philip R Nelson,3 Brian T Peek3 1Pharmacy Benefits Management Services, Department of Veterans Affairs, Hines, IL, 2Wilkes-Barre VA Medical Center, Wilkes-Barre, PA, 3Charles George VA Medical Center, Asheville, NC, USA Purpose: Minimal-risk randomized trials that can be embedded in practice could facilitate learning health-care systems. A cluster-randomized design was proposed to compare treatment strategies by assigning clusters...

  3. Goal-directed intraoperative fluid therapy guided by stroke volume and its variation in high-risk surgical patients : a prospective randomized multicentre study

    NARCIS (Netherlands)

    Scheeren, Thomas W. L.; Wiesenack, Christoph; Gerlach, Herwig; Marx, Gernot

    Perioperative hemodynamic optimisation improves postoperative outcome for patients undergoing high-risk surgery (HRS). In this prospective randomized multicentre study we studied the effects of an individualized, goal-directed fluid management based on continuous stroke volume variation (SVV) and

  4. A random generation approach to pattern library creation for full chip lithographic simulation

    Science.gov (United States)

    Zou, Elain; Hong, Sid; Liu, Limei; Huang, Lucas; Yang, Legender; Kabeel, Aliaa; Madkour, Kareem; ElManhawy, Wael; Kwan, Joe; Du, Chunshan; Hu, Xinyi; Wan, Qijian; Zhang, Recoo

    2017-04-01

    As technology advances, the need for running lithographic (litho) checking for early detection of hotspots before tapeout has become essential. This process is important at all levels—from designing standard cells and small blocks to large intellectual property (IP) and full chip layouts. Litho simulation provides high accuracy for detecting printability issues due to problematic geometries, but it has the disadvantage of slow performance on large designs and blocks [1]. Foundries have found a good compromise solution for running litho simulation on full chips by filtering out potential candidate hotspot patterns using pattern matching (PM), and then performing simulation on the matched locations. The challenge has always been how to easily create a PM library of candidate patterns that provides both comprehensive coverage for litho problems and fast runtime performance. This paper presents a new strategy for generating candidate real design patterns through a random generation approach using a layout schema generator (LSG) utility. The output patterns from the LSG are simulated, and then classified by a scoring mechanism that categorizes patterns according to the severity of the hotspots, probability of their presence in the design, and the likelihood of the pattern causing a hotspot. The scoring output helps to filter out the yield problematic patterns that should be removed from any standard cell design, and also to define potential problematic patterns that must be simulated within a bigger context to decide whether or not they represent an actual hotspot. This flow is demonstrated on SMIC 14nm technology, creating a candidate hotspot pattern library that can be used in full chip simulation with very high coverage and robust performance.

  5. Situational variations in ethnic identity across immigration generations: Implications for acculturative change and cross-cultural adaptation.

    Science.gov (United States)

    Noels, Kimberly A; Clément, Richard

    2015-12-01

    This study examined whether the acculturation of ethnic identity is first evident in more public situations with greater opportunity for intercultural interaction and eventually penetrates more intimate situations. It also investigated whether situational variations in identity are associated with cross-cultural adaptation. First-generation (G1), second-generation (G2) and mixed-parentage second-generation (G2.5) young adult Canadians (n = 137, n = 169, and n = 91, respectively) completed a questionnaire assessing their heritage and Canadian identities across four situational domains (family, friends, university and community), global heritage identity and cross-cultural adaptation. Consistent with the acculturation penetration hypothesis, the results showed Canadian identity was stronger than heritage identity in public domains, but the converse was true in the family domain; moreover, the difference between the identities in the family domain was attenuated in later generations. Situational variability indicated better adaptation for the G1 cohort, but poorer adaptation for the G2.5 cohort. For the G2 cohort, facets of global identity moderated the relation, such that those with a weaker global identity experienced greater difficulties and hassles with greater identity variability but those with a stronger identity did not. These results are interpreted in light of potential interpersonal issues implied by situational variation for each generation cohort. © 2015 International Union of Psychological Science.

  6. The vls antigenic variation systems of Lyme disease Borrelia: eluding host immunity through both random, segmental gene conversion and framework heterogeneity

    Science.gov (United States)

    Norris, Steven J.

    2015-01-01

    Summary Spirochetes that cause Lyme borreliosis (also called Lyme disease) possess the vls locus, encoding an elaborate antigenic variation system. This locus contains the expression site vlsE as well as a contiguous array of vls silent cassettes, which contain variations of the central cassette region of vlsE. The locus is present on one of the many linear plasmids in the organism, e.g. plasmid lp28-1 in the strain B. burgdorferi B31. Changes in the sequence of vlsE occur continuously during mammalian infection and consist of random, segmental, unidirectional recombination events between the silent cassettes and the cassette region of vlsE. These gene conversion events do not occur during in vitro culture or the tick portion of the infection cycle of Borrelia burgdorferi or the other related Borrelia species that cause Lyme disease. The mechanism of recombination is largely unknown, but requires the RuvAB Holliday junction branch migrase. Other features of the vls locus also appear to be required, including cis locations of vlsE and the silent cassettes and high G+C content and GC skew. The vls system is required for long-term survival of Lyme Borrelia in infected mammals and represents an important mechanism of immune evasion. In addition to sequence variation, immune selection also results in significant heterogeneity in the sequence of the surface lipoprotein VlsE. Despite antigenic variation, VlsE generates a robust antibody response, and both full length VlsE and the C6 peptide (corresponding to invariant region 6) are widely used in immunodiagnostic tests for Lyme disease. PMID:26104445

  7. Assessment of the suitability of different random number generators for Monte Carlo simulations in gamma-ray spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Cornejo Diaz, N.; Vergara Gil, A. [Centre for Radiological Protection and Higiene, P.O. Box 6195, Habana (Cuba); Jurado Vargas, M. [Physics Department, University of Extremadura, 06071 Badajoz (Spain)], E-mail: mjv@unex.es

    2010-03-15

    The Monte Carlo method has become a valuable numerical laboratory framework in which to simulate complex physical systems. It is based on the generation of pseudo-random number sequences by numerical algorithms called random generators. In this work we assessed the suitability of different well-known random number generators for the simulation of gamma-ray spectrometry systems during efficiency calibrations. The assessment was carried out in two stages. The generators considered (Delphi's linear congruential, mersenne twister, XorShift, multiplier with carry, universal virtual array, and non-periodic logistic map based generator) were first evaluated with different statistical empirical tests, including moments, correlations, uniformity, independence of terms and the DIEHARD battery of tests. In a second step, an application-specific test was conducted by implementing the generators in our Monte Carlo program DETEFF and comparing the results obtained with them. The calculations were performed with two different CPUs, for a typical HpGe detector and a water sample in Marinelli geometry, with gamma-rays between 59 and 1800 keV. For the Non-periodic Logistic Map based generator, dependence of the most significant bits was evident. This explains the bias, in excess of 5%, of the efficiency values obtained with this generator. The results of the application-specific assessment and the statistical performance of the other algorithms studied indicate their suitability for the Monte Carlo simulation of gamma-ray spectrometry systems for efficiency calculations.

  8. Research of the method of pseudo-random number generation based on asynchronous cellular automata with several active cells

    Directory of Open Access Journals (Sweden)

    Bilan Stepan

    2017-01-01

    Full Text Available To date, there are many tasks that are aimed at studying the dynamic changes in physical processes. These tasks do not give advance known result. The solution of such problems is based on the construction of a dynamic model of the object. Successful structural and functional implementation of the object model can give a positive result in time. This approach uses the task of constructing artificial biological objects. To solve such problems, pseudo-random number generators are used, which also find wide application for information protection tasks. Such generators should have good statistical properties and give a long repetition period of the generated pseudo-random bit sequence. This work is aimed at improving these characteristics. The paper considers the method of forming pseudo-random sequences of numbers on the basis of aperiodic cellular automata with two active cells. A pseudo-random number generator is proposed that generates three bit sequences. The first two bit sequences are formed by the corresponding two active cells in the cellular automaton. The third bit sequence is the result of executing the XOR function over the bits of the first two sequences and it has better characteristics compared to them. The use of cellular automata with two active cells allowed to improve the statistical properties of the formed bit sequence, as well as its repetition period. This is proved by using graphical tests for generators built based on cellular automata using the neighborhoods of von Neumann and Moore. The tests showed high efficiency of the generator based on an asynchronous cellular automaton with the neighborhood of Moore. The proposed pseudo-random number generators have good statistical properties, which makes it possible to use them in information security systems, as well as for simulation tasks of various dynamic processes.

  9. Embedded Platform for Automatic Testing and Optimizing of FPGA Based Cryptographic True Random Number Generators

    Directory of Open Access Journals (Sweden)

    M. Varchola

    2009-12-01

    Full Text Available This paper deals with an evaluation platform for cryptographic True Random Number Generators (TRNGs based on the hardware implementation of statistical tests for FPGAs. It was developed in order to provide an automatic tool that helps to speed up the TRNG design process and can provide new insights on the TRNG behavior as it will be shown on a particular example in the paper. It enables to test sufficient statistical properties of various TRNG designs under various working conditions on the fly. Moreover, the tests are suitable to be embedded into cryptographic hardware products in order to recognize TRNG output of weak quality and thus increase its robustness and reliability. Tests are fully compatible with the FIPS 140 standard and are implemented by the VHDL language as an IP-Core for vendor independent FPGAs. A recent Flash based Actel Fusion FPGA was chosen for preliminary experiments. The Actel version of the tests possesses an interface to the Actel’s CoreMP7 softcore processor that is fully compatible with the industry standard ARM7TDMI. Moreover, identical tests suite was implemented to the Xilinx Virtex 2 and 5 in order to compare the performance of the proposed solution with the performance of already published one based on the same FPGAs. It was achieved 25% and 65% greater clock frequency respectively while consuming almost equal resources of the Xilinx FPGAs. On the top of it, the proposed FIPS 140 architecture is capable of processing one random bit per one clock cycle which results in 311.5 Mbps throughput for Virtex 5 FPGA.

  10. Limited phenotypic variation of hypocalcified amelogenesis imperfecta in a danish five-generation family with a novel FAM83H nonsense mutation

    DEFF Research Database (Denmark)

    Haubek, Dorte; Gjørup, Hans; Jensen, Lillian Gryesten

    2011-01-01

    Limited phenotypic variation of hypocalcified amelogenesis imperfecta in a danish five-generation family with a novel FAM83H nonsense mutation......Limited phenotypic variation of hypocalcified amelogenesis imperfecta in a danish five-generation family with a novel FAM83H nonsense mutation...

  11. Effectiveness of second generation antipsychotics: A systematic review of randomized trials

    Directory of Open Access Journals (Sweden)

    Jørgensen Hugo A

    2008-04-01

    Full Text Available Abstract Background Systematic reviews based on efficacy trials are inconclusive about which second generation antipsychotic drug (SGA should be preferred in normal clinical practice, and studies with longer duration and more pragmatic designs are called for. Effectiveness studies, also known as naturalistic, pragmatic, practical or real life studies, adhere to these principles as they aim to mimic daily clinical practice and have longer follow-up. Objective To review the head-to-head effectiveness of SGAs in the domains of global outcomes, symptoms of disease, and tolerability. Methods Searches were made in Embase, PubMED, and the Cochrane central register of controlled trials for effectiveness studies published from 1980 to 2008, week 1. Different combinations of the keywords antipsychotic*, neuroleptic* AND open, pragmatic, practical, naturalistic, real life, effectiveness, side effect*, unwanted effect*, tolera* AND compar* AND random* were used. Results Sixteen different reports of randomized head-to-head comparisons of SGA effectiveness were located. There were differences regarding sample sizes, inclusion criteria and follow-up periods, as well as sources of financial sponsorship. In acute-phase and first-episode patients no differences between the SGAs were disclosed regarding alleviating symptoms of disease. Olanzapine was associated with more weight gain and adverse effects on serum lipids. In the chronic phase patients olanzapine groups had longer time to discontinuation of treatment and better treatment adherence compared to other SGAs. The majority of studies found no differences between the SGAs in alleviating symptoms of psychosis in chronically ill patients. Olanzapine was associated with more metabolic adverse effects compared to the others SGAs. There were surprisingly few between-drug differences regarding side effects. First generation antipsychotics were associated with lower total mental health care costs in 2 of 3 studies

  12. NullSeq: A Tool for Generating Random Coding Sequences with Desired Amino Acid and GC Contents.

    Directory of Open Access Journals (Sweden)

    Sophia S Liu

    2016-11-01

    Full Text Available The existence of over- and under-represented sequence motifs in genomes provides evidence of selective evolutionary pressures on biological mechanisms such as transcription, translation, ligand-substrate binding, and host immunity. In order to accurately identify motifs and other genome-scale patterns of interest, it is essential to be able to generate accurate null models that are appropriate for the sequences under study. While many tools have been developed to create random nucleotide sequences, protein coding sequences are subject to a unique set of constraints that complicates the process of generating appropriate null models. There are currently no tools available that allow users to create random coding sequences with specified amino acid composition and GC content for the purpose of hypothesis testing. Using the principle of maximum entropy, we developed a method that generates unbiased random sequences with pre-specified amino acid and GC content, which we have developed into a python package. Our method is the simplest way to obtain maximally unbiased random sequences that are subject to GC usage and primary amino acid sequence constraints. Furthermore, this approach can easily be expanded to create unbiased random sequences that incorporate more complicated constraints such as individual nucleotide usage or even di-nucleotide frequencies. The ability to generate correctly specified null models will allow researchers to accurately identify sequence motifs which will lead to a better understanding of biological processes as well as more effective engineering of biological systems.

  13. Goal-independent mechanisms for free response generation: creative and pseudo-random performance share neural substrates.

    Science.gov (United States)

    de Manzano, Örjan; Ullén, Fredrik

    2012-01-02

    To what extent free response generation in different tasks uses common and task-specific neurocognitive processes has remained unclear. Here, we investigated overlap and differences in neural activity during musical improvisation and pseudo-random response generation. Brain activity was measured using fMRI in a group of professional classical pianists, who performed musical improvisation of melodies, pseudo-random key-presses and a baseline condition (sight-reading), on either two, six or twelve keys on a piano keyboard. The results revealed an extensive overlap in neural activity between the two generative conditions. Active regions included the dorsolateral and dorsomedial prefrontal cortices, inferior frontal gyrus, anterior cingulate cortex and pre-SMA. No regions showed higher activity in improvisation than in pseudo-random generation. These findings suggest that the activated regions fulfill generic functions that are utilized in different types of free generation tasks, independent of overall goal. In contrast, pseudo-random generation was accompanied by higher activity than improvisation in several regions. This presumably reflects the participants' musical expertise as well as the pseudo-random generation task's high load on attention, working memory, and executive control. The results highlight the significance of using naturalistic tasks to study human behavior and cognition. No brain activity was related to the size of the response set. We discuss that this may reflect that the musicians were able to use specific strategies for improvisation, by which there was no simple relationship between response set size and neural activity. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Analysis of dynamic Cournot learning models for generation companies based on conjectural variations and forward expectation

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez-Alcaraz, G.; Tovar-Hernandez, Jose H.; Moreno-Goytia, Edgar L. [Departamento de Ingenieria Electrica y Electronica del Instituto Tecnologico de Morelia, Morelia, Mich., Mexico (Mexico)

    2009-12-15

    Electricity spot markets generally operate on an hourly basis; under this condition GENCOs can closely observe their competitors' market behavior. For this purposes, a detailed dynamic model is one of the tools used by GENCOs to understand the behavioral variations of competitors over time. The required abilities to rapidly adjust one's own decision-making create a need for new learning procedures and models. Conjectural variations (CV) have been proposed as a learning approach. In this paper a model based on forward expectations (FE) is proposed as a learning approach, and through illustrative examples it is shown that the market equilibria found by the CV model are also obtained by the FE model. (author)

  15. Aging effect on Executive Control in the Random Number Generation Test

    Directory of Open Access Journals (Sweden)

    Amer Cavalheiro Hamdan

    2006-12-01

    Full Text Available The decline of abilities related to Executive Control –EC with aging has been related with the Pre-Frontal System neurobiological aging. This study compared the score obtained in the Random Number Generation Test (RNG by two groups: 30 college students (older than 18 and 36 elderly (older than 60. This last group was divided according to the criteria of schooling in up to 8 years of schooling and over 8 years of schooling. The results show that the younger participants scored 0,344 ± 0,04 in the RNG test; the elderly with up to 8 years of schooling punctuated 0,432 ± 0,10 and that those who studied for 9 years or more reached a mean of 0,393 ± 0,05. The statistical analysis of these data suggest that the elderly performance in the RNG test (0,420 ± 0,09 was significantly worse when compared to the performance of the younger participants (t (64 = -3,9927; p = 0,0001, which confirms that the manipulation and inhibitory control abilities of information are decreased in older people, probably due to the natural aging process of the Frontal Cortex. Keywords: neuropsychology; aging; executive functions.

  16. Shocking Behavior: Random Wealth in Antebellum Georgia and Human Capital Across Generations.

    Science.gov (United States)

    Bleakley, Hoyt; Ferrie, Joseph

    2016-08-01

    Does the lack of wealth constrain parents' investments in the human capital of their descendants? We conduct a nearly fifty-year followup of an episode in which such constraints would have been plausibly relaxed by a random allocation of substantial wealth to families. We track descendants of participants in Georgia's Cherokee Land Lottery of 1832, in which nearly every adult white male in Georgia took part. Winners received close to the median level of wealth - a large financial windfall orthogonal to participants' underlying characteristics that might have also affected their children's human capital. Although winners had slightly more children than non-winners, they did not send them to school more. Sons of winners have no better adult outcomes (wealth, income, literacy) than the sons of non-winners, and winners' grandchildren do not have higher literacy or school attendance than non-winners' grandchildren. This suggests only a limited role for family financial resources in the formation of human capital in the next generations in this environment and a potentially more important role for other factors that persist through family lines.

  17. Turbulence generation by a shock wave interacting with a random density inhomogeneity field

    Science.gov (United States)

    Huete Ruiz de Lira, C.

    2010-12-01

    When a planar shock wave interacts with a random pattern of pre-shock density non-uniformities, it generates an anisotropic turbulent velocity/vorticity field. This turbulence plays an important role in the early stages of the mixing process in a compressed fluid. This situation emerges naturally in a shock interaction with weakly inhomogeneous deuterium-wicked foam targets in inertial confinement fusion and with density clumps/clouds in astrophysics. We present an exact small-amplitude linear theory describing such an interaction. It is based on the exact theory of time and space evolution of the perturbed quantities behind a corrugated shock front for a single-mode pre-shock non-uniformity. Appropriate mode averaging in two dimensions results in closed analytical expressions for the turbulent kinetic energy, degree of anisotropy of velocity and vorticity fields in the shocked fluid, shock amplification of the density non-uniformity and sonic energy flux radiated downstream. These explicit formulae are further simplified in the important asymptotic limits of weak/strong shocks and highly compressible fluids. A comparison with the related problem of a shock interacting with a pre-shock isotropic vorticity field is also presented.

  18. Shocking Behavior: Random Wealth in Antebellum Georgia and Human Capital Across Generations

    Science.gov (United States)

    Bleakley, Hoyt; Ferrie, Joseph

    2017-01-01

    Does the lack of wealth constrain parents’ investments in the human capital of their descendants? We conduct a nearly fifty-year followup of an episode in which such constraints would have been plausibly relaxed by a random allocation of substantial wealth to families. We track descendants of participants in Georgia’s Cherokee Land Lottery of 1832, in which nearly every adult white male in Georgia took part. Winners received close to the median level of wealth – a large financial windfall orthogonal to participants’ underlying characteristics that might have also affected their children’s human capital. Although winners had slightly more children than non-winners, they did not send them to school more. Sons of winners have no better adult outcomes (wealth, income, literacy) than the sons of non-winners, and winners’ grandchildren do not have higher literacy or school attendance than non-winners’ grandchildren. This suggests only a limited role for family financial resources in the formation of human capital in the next generations in this environment and a potentially more important role for other factors that persist through family lines. PMID:28529385

  19. Mitochondrial Genome Variation after Hybridization and Differences in the First and Second Generation Hybrids of Bream Fishes.

    Directory of Open Access Journals (Sweden)

    Wei-Zhuo Zhang

    Full Text Available Hybridization plays an important role in fish breeding. Bream fishes contribute a lot to aquaculture in China due to their economically valuable characteristics and the present study included five bream species, Megalobrama amblycephala, Megalobrama skolkovii, Megalobrama pellegrini, Megalobrama terminalis and Parabramis pekinensis. As maternal inheritance of mitochondrial genome (mitogenome involves species specific regulation, we aimed to investigate in which way the inheritance of mitogenome is affected by hybridization in these fish species. With complete mitogenomes of 7 hybrid groups of bream species being firstly reported in the present study, a comparative analysis of 17 mitogenomes was conducted, including representatives of these 5 bream species, 6 first generation hybrids and 6 second generation hybrids. The results showed that these 17 mitogenomes shared the same gene arrangement, and had similar gene size and base composition. According to the phylogenetic analyses, all mitogenomes of the hybrids were consistent with a maternal inheritance. However, a certain number of variable sites were detected in all F1 hybrid groups compared to their female parents, especially in the group of M. terminalis (♀ × M. amblycephala (♂ (MT×MA, with a total of 86 variable sites between MT×MA and its female parent. Among the mitogenomes genes, the protein-coding gene nd5 displayed the highest variability. The number of variation sites was found to be related to phylogenetic relationship of the parents: the closer they are, the lower amount of variation sites their hybrids have. The second generation hybrids showed less mitogenome variation than that of first generation hybrids. The non-synonymous and synonymous substitution rates (dN/dS were calculated between all the hybrids with their own female parents and the results indicated that most PCGs were under negative selection.

  20. A generator for unique quantum random numbers based on vacuum states

    DEFF Research Database (Denmark)

    Gabriel, C.; Wittmann, C.; Sych, D.

    2010-01-01

    Random numbers are a valuable component in diverse applications that range from simulations(1) over gambling to cryptography(2,3). The quest for true randomness in these applications has engendered a large variety of different proposals for producing random numbers based on the foundational unpre...

  1. Engineering practice variation through provider agreement: a cluster-randomized feasibility trial

    Directory of Open Access Journals (Sweden)

    McCarren M

    2014-10-01

    Full Text Available Madeline McCarren,1 Elaine L Twedt,1 Faizmohamed M Mansuri,2 Philip R Nelson,3 Brian T Peek3 1Pharmacy Benefits Management Services, Department of Veterans Affairs, Hines, IL, 2Wilkes-Barre VA Medical Center, Wilkes-Barre, PA, 3Charles George VA Medical Center, Asheville, NC, USA Purpose: Minimal-risk randomized trials that can be embedded in practice could facilitate learning health-care systems. A cluster-randomized design was proposed to compare treatment strategies by assigning clusters (eg, providers to “favor” a particular drug, with providers retaining autonomy for specific patients. Patient informed consent might be waived, broadening inclusion. However, it is not known if providers will adhere to the assignment or whether institutional review boards will waive consent. We evaluated the feasibility of this trial design.Subjects and methods: Agreeable providers were randomized to “favor” either hydrochlorothiazide or chlorthalidone when starting patients on thiazide-type therapy for hypertension. The assignment applied when the provider had already decided to start a thiazide, and providers could deviate from the strategy as needed. Prescriptions were aggregated to produce a provider strategy-adherence rate.Results: All four institutional review boards waived documentation of patient consent. Providers (n=18 followed their assigned strategy for most of their new thiazide prescriptions (n=138 patients. In the “favor hydrochlorothiazide” group, there was 99% adherence to that strategy. In the “favor chlorthalidone” group, chlorthalidone comprised 77% of new thiazide starts, up from 1% in the pre-study period. When the assigned strategy was followed, dosing in the recommended range was 48% for hydrochlorothiazide (25–50 mg/day and 100% for chlorthalidone (12.5–25.0 mg/day. Providers were motivated to participate by a desire to contribute to a comparative effectiveness study. A study promotional mug, provider information

  2. Accumulation, elimination, sequestration, and genetic variation of lead (Pb(2+)) loads within and between generations of Drosophila melanogaster.

    Science.gov (United States)

    Peterson, Elizabeth K; Wilson, Diane T; Possidente, Bernard; McDaniel, Phillip; Morley, Eric J; Possidente, Debra; Hollocher, Kurt T; Ruden, Douglas M; Hirsch, Helmut V B

    2017-08-01

    We examined accumulation, sequestration, elimination, and genetic variation for lead (Pb) loads within and between generations of Drosophila melanogaster. Flies were reared in control or leaded medium at various doses and tested for their Pb loads at different stages of development (larvae, eclosion, newly-eclosed adults, and mature adults). Pb loads were tested using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). We found that D. melanogaster readily accumulated Pb throughout their lifespan and the levels of accumulation increased with Pb exposure in the medium. Wandering third-instar larvae accumulated more Pb than mature adults; this phenomenon may be due to elimination of Pb in the pupal cases during eclosion and/or depuration in adults post-eclosion. The accumulated Pb in mature adults was not transferred to F1 mature adult offspring. Using a set of recombinant inbred strains, we identified a quantitative trait locus for adult Pb loads and found that genetic variation accounted for 34% of the variance in Pb load. We concluded that D. melanogaster is a useful model organism for evaluating changes in Pb loads during development, as well as between generations. Furthermore, we found that genetic factors can influence Pb loads; this provides an essential foundation for evaluating phenotypic variation induced by the toxic effects of Pb. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Genomic tools to improve progress and preserve variation for future generations

    Science.gov (United States)

    Use of genomic tools has greatly decreased generation intervals and increased genetic progress in dairy cattle, but faster selection cycles can also increase rates of inbreeding per unit of time. Average pedigree inbreeding of Holstein cows increased from 4.6% in 2000 to 5.6% in 2009 to 6.6% in 201...

  4. Using character valence in computer generated music to produce variation aligned to a storyline

    CSIR Research Space (South Africa)

    Featherstone, Coral

    2015-07-01

    Full Text Available that sentiment in the text of a novel can be used to automatically generate simple piano music that reflects the same sentiment as the novel. This study wished to establish a method whereby, if after aligning the text with the melody, the sentiment in the words...

  5. Linguistic variation between generations in A Illa de Ons (Bueu. “Seseo”

    Directory of Open Access Journals (Sweden)

    José Dopazo Entenza

    2018-01-01

    Full Text Available The Isle of Ons from the early nineteenth century until its depopulation in the 1970s, had an important speech community that has developed features and linguistic peculiarities. After the exodus of that population into the nearest peninsulas (O Salnés and O Morrazo, younger people showed greater permeability talks with the destinations. The latest generations are the most influenced for the place where they live, and the standard of Galician and Spanish. The model allows time apparent change of approach to a speech community of the Isle of Ons through three generations to describe the fricatives that the speakers use (apical, laminar and interdental and the dependences to variables like sex, education level, language and socioeconomic status. For this, I have 24 recordings transcribed with a total of 32 informants. We can see that the first generations always has seseo, alternating between apical and laminar (predominantly the last. The second has a greater hesitation as to the use or not of seseo, being the most apical what is used in this mode. Finally, the third generation shows mostly fricative interdental therefore not use the seseo and, in the case of use, it is the type apical.

  6. Generation of Aptamers from A Primer-Free Randomized ssDNA Library Using Magnetic-Assisted Rapid Aptamer Selection

    Science.gov (United States)

    Tsao, Shih-Ming; Lai, Ji-Ching; Horng, Horng-Er; Liu, Tu-Chen; Hong, Chin-Yih

    2017-04-01

    Aptamers are oligonucleotides that can bind to specific target molecules. Most aptamers are generated using random libraries in the standard systematic evolution of ligands by exponential enrichment (SELEX). Each random library contains oligonucleotides with a randomized central region and two fixed primer regions at both ends. The fixed primer regions are necessary for amplifying target-bound sequences by PCR. However, these extra-sequences may cause non-specific bindings, which potentially interfere with good binding for random sequences. The Magnetic-Assisted Rapid Aptamer Selection (MARAS) is a newly developed protocol for generating single-strand DNA aptamers. No repeat selection cycle is required in the protocol. This study proposes and demonstrates a method to isolate aptamers for C-reactive proteins (CRP) from a randomized ssDNA library containing no fixed sequences at 5‧ and 3‧ termini using the MARAS platform. Furthermore, the isolated primer-free aptamer was sequenced and binding affinity for CRP was analyzed. The specificity of the obtained aptamer was validated using blind serum samples. The result was consistent with monoclonal antibody-based nephelometry analysis, which indicated that a primer-free aptamer has high specificity toward targets. MARAS is a feasible platform for efficiently generating primer-free aptamers for clinical diagnoses.

  7. Conservation of the C-type lectin fold for massive sequence variation in a Treponema diversity-generating retroelement

    Energy Technology Data Exchange (ETDEWEB)

    Le Coq, Johanne; Ghosh, Partho (UCSD)

    2012-06-19

    Anticipatory ligand binding through massive protein sequence variation is rare in biological systems, having been observed only in the vertebrate adaptive immune response and in a phage diversity-generating retroelement (DGR). Earlier work has demonstrated that the prototypical DGR variable protein, major tropism determinant (Mtd), meets the demands of anticipatory ligand binding by novel means through the C-type lectin (CLec) fold. However, because of the low sequence identity among DGR variable proteins, it has remained unclear whether the CLec fold is a general solution for DGRs. We have addressed this problem by determining the structure of a second DGR variable protein, TvpA, from the pathogenic oral spirochete Treponema denticola. Despite its weak sequence identity to Mtd ({approx}16%), TvpA was found to also have a CLec fold, with predicted variable residues exposed in a ligand-binding site. However, this site in TvpA was markedly more variable than the one in Mtd, reflecting the unprecedented approximate 10{sup 20} potential variability of TvpA. In addition, similarity between TvpA and Mtd with formylglycine-generating enzymes was detected. These results provide strong evidence for the conservation of the formylglycine-generating enzyme-type CLec fold among DGRs as a means of accommodating massive sequence variation.

  8. Some Bounds on the Deviation Probability for Sums of Nonnegative Random Variables Using Upper Polynomials, Moment and Probability Generating Functions

    OpenAIRE

    From, Steven G.

    2010-01-01

    We present several new bounds for certain sums of deviation probabilities involving sums of nonnegative random variables. These are based upon upper bounds for the moment generating functions of the sums. We compare these new bounds to those of Maurer [2], Bernstein [4], Pinelis [16], and Bentkus [3]. We also briefly discuss the infinitely divisible distributions case.

  9. Non-random seasonal variation in the structure of a Mediterranean snake community

    Directory of Open Access Journals (Sweden)

    E. Filippi

    2007-05-01

    Full Text Available The community structure in relation to habitat type was studied in a Mediterranean community of snakes from Canale Monterano, central Italy. Habitat data for snakes were analysed both overall and divided by season, i.e. spring (April–June and summer (July–September. Community analyses were performed using null models (RA2 and RA3 algorithms and Monte Carlo simulations on habitat niche overlap estimates. Null models suggested that the community was assembled non-randomly (according to RA2 but not RA3, indicating that the generalist-specialist nature (the number of resource states, but not necessarily the types used by each species in the assemblage reduced ecological similarity. Similar results were reached also performing the same null model procedures on the spring datasets, whereas no structure emerged during summer either by RA2 or RA3 algorithms. In general, this study suggests that the community structure of snakes during spring may be shaped by the different eco-physiological needs of the various species (probably, the differential tolerance to cold and the consequent needs of finding suitable hibernacula, whereas the lack of structure during summer may be caused by the between-species similar foraging needs.

  10. A block variational procedure for the iterative diagonalization of non-Hermitian random-phase approximation matrices.

    Science.gov (United States)

    Rocca, Dario; Bai, Zhaojun; Li, Ren-Cang; Galli, Giulia

    2012-01-21

    We present a technique for the iterative diagonalization of random-phase approximation (RPA) matrices, which are encountered in the framework of time-dependent density-functional theory (TDDFT) and the Bethe-Salpeter equation. The non-Hermitian character of these matrices does not permit a straightforward application of standard iterative techniques used, i.e., for the diagonalization of ground state Hamiltonians. We first introduce a new block variational principle for RPA matrices. We then develop an algorithm for the simultaneous calculation of multiple eigenvalues and eigenvectors, with convergence and stability properties similar to techniques used to iteratively diagonalize Hermitian matrices. The algorithm is validated for simple systems (Na(2) and Na(4)) and then used to compute multiple low-lying TDDFT excitation energies of the benzene molecule. © 2012 American Institute of Physics

  11. Temperature variation induced by the pulsed-periodic laser pumping under terahertz wave generation

    Science.gov (United States)

    Kitaeva, G. Kh; Moiseenko, E. V.; Shepelev, A. V.

    2017-09-01

    During nonlinear-optical parametric frequency conversion the heat-related effects occur, considerably influencing the conversion process. We develop versatile methods for analytic and numerical calculations of thermo-optical parameters and the temperature distribution inside a non-linear crystal pumped by periodic laser pulses. As an example, numerical results are presented for a number of laser-based schemes actual for the non-linear optical terahertz wave generation and parametric frequency conversion processes.

  12. Regional variations in the health, environmental, and climate benefits of wind and solar generation

    OpenAIRE

    Siler-Evans, Kyle; Azevedo, Inês Lima; Morgan, M. Granger; Apt, Jay

    2013-01-01

    When wind or solar energy displace conventional generation, the reduction in emissions varies dramatically across the United States. Although the Southwest has the greatest solar resource, a solar panel in New Jersey displaces significantly more sulfur dioxide, nitrogen oxides, and particulate matter than a panel in Arizona, resulting in 15 times more health and environmental benefits. A wind turbine in West Virginia displaces twice as much carbon dioxide as the same turbine in California. De...

  13. Random walks with long-range steps generated by functions of Laplacian matrices

    OpenAIRE

    Riascos, A. P.; Michelitsch, T. M.; Collet, B. A.; Nowakowski, A. F.; Nicolleau, F. C. G. A

    2017-01-01

    In this paper, we explore different Markovian random walk strategies on networks with transition probabilities between nodes defined in terms of functions of the Laplacian matrix. We generalize random walk strategies with local information in the Laplacian matrix, that describes the connections of a network, to a dynamics determined by functions of this matrix. The resulting processes is non-local allowing transitions of the random walker from one node to nodes beyond its nearest neighbors. I...

  14. Polymorphic variation in CHAT gene modulates general cognitive ability: An association study with random student cohort.

    Science.gov (United States)

    Liu, Xu; Shi, Yuanyu; Niu, Binbin; Shi, Zhangyan; Li, Junlin; Ma, Zhe; Wang, Jian; Gong, Pingyuan; Zheng, Anyun; Zhang, Fuchang; Gao, Xiaocai; Zhang, Kejin

    2016-03-23

    The choline O-acetyltransferase (CHAT) gene has been associated with various human disorders that involve cognitive impairment or deficiency. However, the influence of disease-associated variants of CHAT on normal individuals remains dubious. Here we demonstrated the impact of CHAT sequence variants (G-120A) on general human cognitive ability in a cohort of 750 Chinese undergraduate students. A multiple choice questionnaire was used to obtain basic demographic information, such as parents' occupations and education levels. We also administered and scored the Raven's Standard Progressive Matrices (RSPM). A one-way analysis of variance (ANOVA) and Kruskal-Wallis test (K-W) revealed a significant association between sequence polymorphisms of G-120A and individuals' Raven score (p=0.031 for ANOVA and p=0.026 for K-W tests). Moreover, further hierarchical analysis showed a similar trend in the association between G-120A variants and Raven scores only in the female subjects (p=0.008 for ANOVA and p=0.024 for K-W tests) but not in the male subjects. The results of a multiple linear regression confirmed that after we controlled gender, age, birthplace and other non-genetic factors, CHAT G-120A polymorphisms still significantly influenced individual Raven scores (B=-0.70, SE=0.28, t=-2.50, p=0.013). Our results demonstrated that sequence variants of CHAT were associated with human cognitive ability in not only patients with psychiatric disorders but also normal healthy individuals. However, some issues remained indeterminable, such as gender differences and the extent of the influence on individuals' general cognitive abilities; thus, the further research using an independent random sample was required. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  15. Variations in reporting of outcomes in randomized trials on diet and physical activity in pregnancy: A systematic review.

    Science.gov (United States)

    Rogozińska, Ewelina; Marlin, Nadine; Yang, Fen; Dodd, Jodie M; Guelfi, Kym; Teede, Helena; Surita, Fernanda; Jensen, Dorte M; Geiker, Nina R W; Astrup, Arne; Yeo, SeonAe; Kinnunen, Tarja I; Stafne, Signe N; Cecatti, Jose G; Bogaerts, Annick; Hauner, Hans; Mol, Ben W; Scudeller, Tânia T; Vinter, Christina A; Renault, Kristina M; Devlieger, Roland; Thangaratinam, Shakila; Khan, Khalid S

    2017-07-01

    Trials on diet and physical activity in pregnancy report on various outcomes. We aimed to assess the variations in outcomes reported and their quality in trials on lifestyle interventions in pregnancy. We searched major databases without language restrictions for randomized controlled trials on diet and physical activity-based interventions in pregnancy up to March 2015. Two independent reviewers undertook study selection and data extraction. We estimated the percentage of papers reporting 'critically important' and 'important' outcomes. We defined the quality of reporting as a proportion using a six-item questionnaire. Regression analysis was used to identify factors affecting this quality. Sixty-six randomized controlled trials were published in 78 papers (66 main, 12 secondary). Gestational diabetes (57.6%, 38/66), preterm birth (48.5%, 32/66) and cesarian section (60.6%, 40/66), were the commonly reported 'critically important' outcomes. Gestational weight gain (84.5%, 56/66) and birth weight (87.9%, 58/66) were reported in most papers, although not considered critically important. The median quality of reporting was 0.60 (interquartile range 0.25, 0.83) for a maximum score of one. Study and journal characteristics did not affect quality. Many studies on lifestyle interventions in pregnancy do not report critically important outcomes, highlighting the need for core outcome set development. © 2017 Japan Society of Obstetrics and Gynecology.

  16. Intraoperative monitoring of stroke volume variation versus central venous pressure in laparoscopic liver surgery: a randomized prospective comparative trial.

    Science.gov (United States)

    Ratti, Francesca; Cipriani, Federica; Reineke, Raffaella; Catena, Marco; Paganelli, Michele; Comotti, Laura; Beretta, Luigi; Aldrighetti, Luca

    2016-02-01

    Central venous pressure (CVP) is used as a marker of cardiac preload to control intraoperative blood loss in open hepatectomies, while its reliability in laparoscopy is less certain. The aim of this randomized prospective trial was to evaluate the outcome of laparoscopic resections performed with stroke volume variation (SVV) or CVP monitoring. All candidates for laparoscopic liver resection were assigned randomly to SVV or to CVP groups. Outcome was evaluated included conversion rate, cause of conversion, intraoperative blood loss, need for transfusions, length of surgery and postoperative results. Ninety consecutive patients were enrolled: both SVV and CVP groups included 45 patients each and were comparable in terms of patient and disease characteristics. A reduced rate of conversion was recorded in the SVV compared to the CVP group (6.7% and 17.8% respectively, p = 0.02). Blood loss was lower in the SVV group (150 mL), compared to the CVP group (300 mL, p = 0.04). Morbidity, mortality, length of stay and functional recovery were comparable. On multivariate analysis, lesion location, extent of hepatectomy and type of cardiac preload monitoring were associated significantly to risk of conversion. SVV monitoring in laparoscopic liver surgery improves intraoperative outcome, thus enhancing the benefits of the minimally-invasive approach and fast-track protocols. Copyright © 2015 International Hepato-Pancreato-Biliary Association Inc. Published by Elsevier Ltd. All rights reserved.

  17. Variation in Generational Perceptions of Child Health and Well-being.

    Science.gov (United States)

    Freed, Gary L; Davis, Matthew M; Singer, Dianne C; Gebremariam, Acham; Schultz, Sara L; Matos-Moreno, Amilcar; Wietecha, Mark

    2017-09-12

    To assess adults' perceptions regarding the health and well-being of children today relative to their own health and well-being as youth and the potential for intergenerational differences in those perceptions. A cross-sectional, Internet-based survey of a nationally representative household sample was conducted using GfK Custom Research's Web-enabled KnowledgePanel, a probability-based panel representative of the US population. We assessed perceptions of children's health and well-being today compared to when respondents were growing up, including physical and mental health; and children's education, exercise, diet, health care, safety of communities, and emotional support from families, groups, and organizations. Overall, 1330 (65%) of 2047 adult respondents completed the survey. Only 26% of respondents believed that the current physical health of children, and 14% that the current mental health of children, is better today than when they were growing up. There was a significant trend among generations, with a greater proportion of older generations perceiving the physical health of children to be better today. Only 15% of respondents reported the chances for a child to grow up with good mental health in the future are "better" now than when they were growing up. Adults across all generations in the United States today view children's health as unlikely to meet the goals of the American Dream of continuous improvement. Although demographic changes require continued focus on our aging population, we must equally recognize the importance of advancing a healthy future for our nation's children, who will assume the mantle of our future. Copyright © 2017 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

  18. Variation of power generation at different buffer types and conductivities in single chamber microbial fuel cells

    KAUST Repository

    Nam, Joo-Youn

    2010-01-15

    Microbial fuel cells (MFCs) are operated with solutions containing various chemical species required for the growth of electrochemically active microorganisms including nutrients and vitamins, substrates, and chemical buffers. Many different buffers are used in laboratory media, but the effects of these buffers and their inherent electrolyte conductivities have not been examined relative to current generation in MFCs. We investigated the effect of several common buffers (phosphate, MES, HEPES, and PIPES) on power production in single chambered MFCs compared to a non-buffered control. At the same concentrations the buffers produced different solution conductivities which resulted in different ohmic resistances and power densities. Increasing the solution conductivities to the same values using NaCl produced comparable power densities for all buffers. Very large increases in conductivity resulted in a rapid voltage drop at high current densities. Our results suggest that solution conductivity at a specific pH for each buffer is more important in MFC studies than the buffer itself given relatively constant pH conditions. Based on our analysis of internal resistance and a set neutral pH, phosphate and PIPES are the most useful buffers of those examined here because pH was maintained close to the pKa of the buffer, maximizing the ability of the buffer to contribute to increase current generation at high power densities. © 2009 Elsevier B.V. All rights reserved.

  19. Variation of power generation at different buffer types and conductivities in single chamber microbial fuel cells.

    Science.gov (United States)

    Nam, Joo-Youn; Kim, Hyun-Woo; Lim, Kyeong-Ho; Shin, Hang-Sik; Logan, Bruce E

    2010-01-15

    Microbial fuel cells (MFCs) are operated with solutions containing various chemical species required for the growth of electrochemically active microorganisms including nutrients and vitamins, substrates, and chemical buffers. Many different buffers are used in laboratory media, but the effects of these buffers and their inherent electrolyte conductivities have not been examined relative to current generation in MFCs. We investigated the effect of several common buffers (phosphate, MES, HEPES, and PIPES) on power production in single chambered MFCs compared to a non-buffered control. At the same concentrations the buffers produced different solution conductivities which resulted in different ohmic resistances and power densities. Increasing the solution conductivities to the same values using NaCl produced comparable power densities for all buffers. Very large increases in conductivity resulted in a rapid voltage drop at high current densities. Our results suggest that solution conductivity at a specific pH for each buffer is more important in MFC studies than the buffer itself given relatively constant pH conditions. Based on our analysis of internal resistance and a set neutral pH, phosphate and PIPES are the most useful buffers of those examined here because pH was maintained close to the pK(a) of the buffer, maximizing the ability of the buffer to contribute to increase current generation at high power densities. Copyright 2009 Elsevier B.V. All rights reserved.

  20. Random number generation in bilingual Balinese and German students: preliminary findings from an exploratory cross-cultural study.

    Science.gov (United States)

    Strenge, Hans; Lesmana, Cokorda Bagus Jaya; Suryani, Luh Ketut

    2009-08-01

    Verbal random number generation is a procedurally simple task to assess executive function and appears ideally suited for the use under diverse settings in cross-cultural research. The objective of this study was to examine ethnic group differences between young adults in Bali (Indonesia) and Kiel (Germany): 50 bilingual healthy students, 30 Balinese and 20 Germans, attempted to generate a random sequence of the digits 1 to 9. In Balinese participants, randomization was done in Balinese (native language L1) and Indonesian (first foreign language L2), in German subjects in the German (L1) and English (L2) languages. 10 of 30 Balinese (33%), but no Germans, were unable to inhibit habitual counting in more than half of the responses. The Balinese produced significantly more nonrandom responses than the Germans with higher rates of counting and significantly less occurrence of the digits 2 and 3 in L1 compared with L2. Repetition and cycling behavior did not differ between the four languages. The findings highlight the importance of taking into account culture-bound psychosocial factors for Balinese individuals when administering and interpreting a random number generation test.

  1. Control Strategy for Power Loss Reduction considering Load Variation with Large Penetration of Distributed Generation

    Directory of Open Access Journals (Sweden)

    Chang Liu

    2017-01-01

    Full Text Available With the increase of penetration of distribution in distribution systems, the problems of power loss increase and short-circuit capacity beyond the rated capacity of the circuit breaker will become more serious. In this paper, a methodology (modified BPSO is presented for network reconfiguration which is based on the hybrid approach of Tabu search and BPSO algorithms to prevent the local convergence and to decrease the calculation time using double fitness to consider the constraints. Moreover, an average load simulated method (ALS method considering load variation is proposed such that the average load value is used instead of the actual load for calculation. Finally, from a case study, the results of simulation certify that the approaches will decrease drastically the losses and improve the voltage profiles obviously; at the same time, the short-circuit capacity is also decreased into smaller shut-off capacity of the circuit breaker. The power losses will not be increased too much even if the short-circuit capacity constraint is considered; voltage profiles are better with the constraint of short-circuit capacity considered. The ALS method is simple and the calculation time is fast.

  2. Regional variations in the health, environmental, and climate benefits of wind and solar generation.

    Science.gov (United States)

    Siler-Evans, Kyle; Azevedo, Inês Lima; Morgan, M Granger; Apt, Jay

    2013-07-16

    When wind or solar energy displace conventional generation, the reduction in emissions varies dramatically across the United States. Although the Southwest has the greatest solar resource, a solar panel in New Jersey displaces significantly more sulfur dioxide, nitrogen oxides, and particulate matter than a panel in Arizona, resulting in 15 times more health and environmental benefits. A wind turbine in West Virginia displaces twice as much carbon dioxide as the same turbine in California. Depending on location, we estimate that the combined health, environmental, and climate benefits from wind or solar range from $10/MWh to $100/MWh, and the sites with the highest energy output do not yield the greatest social benefits in many cases. We estimate that the social benefits from existing wind farms are roughly 60% higher than the cost of the Production Tax Credit, an important federal subsidy for wind energy. However, that same investment could achieve greater health, environmental, and climate benefits if it were differentiated by region.

  3. SPATIAL VARIATION IN POVERTY-GENERATING PROCESSES: CHILD POVERTY IN THE UNITED STATES

    Science.gov (United States)

    Curtis, Katherine J.; Voss, Paul R.; Long, David D.

    2012-01-01

    This study builds on research demonstrating that sub-regions within the United States have different processes that abet poverty and that child poverty is spatially differentiated. We focus on the social attributes of the local area to assess what the geographic place represents in terms of social characteristics, namely racial/ethnic composition and economic structure, and to resolve apparent inconsistencies in poverty research. Using spatial regime and spatial error regression techniques to analyze county census data, we examine spatial differentiation in the relationships that generate child poverty. Our approach addresses the conceptual and technical aspects of spatial inequality. Results show that local-area processes are at play with implications for more nuanced theoretical models and anti-poverty policies that consider systematic differences in factors contributing to child poverty according to the racial/ethnic and economic contexts. PMID:23017703

  4. Introgression from domestic goat generated variation at the major histocompatibility complex of Alpine ibex.

    Directory of Open Access Journals (Sweden)

    Christine Grossen

    2014-06-01

    Full Text Available The major histocompatibility complex (MHC is a crucial component of the vertebrate immune system and shows extremely high levels of genetic polymorphism. The extraordinary genetic variation is thought to be ancient polymorphisms maintained by balancing selection. However, introgression from related species was recently proposed as an additional mechanism. Here we provide evidence for introgression at the MHC in Alpine ibex (Capra ibex ibex. At a usually very polymorphic MHC exon involved in pathogen recognition (DRB exon 2, Alpine ibex carried only two alleles. We found that one of these DRB alleles is identical to a DRB allele of domestic goats (Capra aegagrus hircus. We sequenced 2489 bp of the coding and non-coding regions of the DRB gene and found that Alpine ibex homozygous for the goat-type DRB exon 2 allele showed nearly identical sequences (99.8% to a breed of domestic goats. Using Sanger and RAD sequencing, microsatellite and SNP chip data, we show that the chromosomal region containing the goat-type DRB allele has a signature of recent introgression in Alpine ibex. A region of approximately 750 kb including the DRB locus showed high rates of heterozygosity in individuals carrying one copy of the goat-type DRB allele. These individuals shared SNP alleles both with domestic goats and other Alpine ibex. In a survey of four Alpine ibex populations, we found that the region surrounding the DRB allele shows strong linkage disequilibria, strong sequence clustering and low diversity among haplotypes carrying the goat-type allele. Introgression at the MHC is likely adaptive and introgression critically increased MHC DRB diversity in the genetically impoverished Alpine ibex. Our finding contradicts the long-standing view that genetic variability at the MHC is solely a consequence of ancient trans-species polymorphism. Introgression is likely an underappreciated source of genetic diversity at the MHC and other loci under balancing selection.

  5. Combined Effects Of Stress Work And Heat Generation On MHD Natural Convection Flow Along A Vertical Flat Plate With Power Law Variation Of Uniform Surface Temperature

    National Research Council Canada - National Science Library

    Mohammad Mahfuzul Islam; Md. M. Alam; M. M. Parvez; M. A. Rahman

    2015-01-01

    Abstract In this paper is presented to study conjugate effects of stress work and heat generation on MHD natural convection flow along a vertical flat plate with power law variation of surface temperature...

  6. Features of surfaces with random structure variations: Poster at Strategic Workshop "Principles and Development of Bio-Inspired Materials", 13 - 15 April 2010; Vienna, Austria

    OpenAIRE

    Mölders, N.; Nellesen, A.; Bertling, J.

    2010-01-01

    In contrast to the precision requested in industrial processing, biological structures only seem to possess a perfect, uniform regularity. Within the recurring patterns and periodic self-similar structures a randomly acting variation appears to be present. The main goal of this work is to elucidate whether these variations are irrelevant or related to the particular functionality of a surface or if they are just a result of stimulus- environmental interaction and genetical predisposition. The...

  7. Regional variations in the health, environmental, and climate benefits of wind and solar generation

    Science.gov (United States)

    Siler-Evans, Kyle; Azevedo, Inês Lima; Morgan, M. Granger; Apt, Jay

    2013-01-01

    When wind or solar energy displace conventional generation, the reduction in emissions varies dramatically across the United States. Although the Southwest has the greatest solar resource, a solar panel in New Jersey displaces significantly more sulfur dioxide, nitrogen oxides, and particulate matter than a panel in Arizona, resulting in 15 times more health and environmental benefits. A wind turbine in West Virginia displaces twice as much carbon dioxide as the same turbine in California. Depending on location, we estimate that the combined health, environmental, and climate benefits from wind or solar range from $10/MWh to $100/MWh, and the sites with the highest energy output do not yield the greatest social benefits in many cases. We estimate that the social benefits from existing wind farms are roughly 60% higher than the cost of the Production Tax Credit, an important federal subsidy for wind energy. However, that same investment could achieve greater health, environmental, and climate benefits if it were differentiated by region. PMID:23798431

  8. Noise, transient dynamics, and the generation of realistic interspike interval variation in square-wave burster neurons

    Science.gov (United States)

    Marin, Bóris; Pinto, Reynaldo Daniel; Elson, Robert C.; Colli, Eduardo

    2014-10-01

    First return maps of interspike intervals for biological neurons that generate repetitive bursts of impulses can display stereotyped structures (neuronal signatures). Such structures have been linked to the possibility of multicoding and multifunctionality in neural networks that produce and control rhythmical motor patterns. In some cases, isolating the neurons from their synaptic network reveals irregular, complex signatures that have been regarded as evidence of intrinsic, chaotic behavior. We show that incorporation of dynamical noise into minimal neuron models of square-wave bursting (either conductance-based or abstract) produces signatures akin to those observed in biological examples, without the need for fine tuning of parameters or ad hoc constructions for inducing chaotic activity. The form of the stochastic term is not strongly constrained and can approximate several possible sources of noise, e.g., random channel gating or synaptic bombardment. The cornerstone of this signature generation mechanism is the rich, transient, but deterministic dynamics inherent in the square-wave (saddle-node and homoclinic) mode of neuronal bursting. We show that noise causes the dynamics to populate a complex transient scaffolding or skeleton in state space, even for models that (without added noise) generate only periodic activity (whether in bursting or tonic spiking mode).

  9. Non-random expression of ribosomal DNA units in a grasshopper showing high intragenomic variation for the ITS2 region.

    Science.gov (United States)

    Ruiz-Estévez, M; Ruiz-Ruano, F J; Cabrero, J; Bakkali, M; Perfectti, F; López-León, M D; Camacho, J P M

    2015-06-01

    We analyse intragenomic variation of the ITS2 internal transcribed spacer of ribosomal DNA (rDNA) in the grasshopper Eyprepocnemis plorans, by means of tagged PCR 454 amplicon sequencing performed on both genomic DNA (gDNA) and RNA-derived complementary DNA (cDNA), using part of the ITS2 flanking coding regions (5.8S and 28S rDNA) as an internal control for sequencing errors. Six different ITS2 haplotypes (i.e. variants for at least one nucleotide in the complete ITS2 sequence) were found in a single population, one of them (Hap4) being specific to a supernumerary (B) chromosome. The analysis of both gDNA and cDNA from the same individuals provided an estimate of the expression efficiency of the different haplotypes. We found random expression (i.e. about similar recovery in gDNA and cDNA) for three haplotypes (Hap1, Hap2 and Hap5), but significant underexpression for three others (Hap3, Hap4 and Hap6). Hap4 was the most extremely underexpressed and, remarkably, it showed the lowest sequence conservation for the flanking 5.8-28S coding regions in the gDNA reads but the highest conservation (100%) in the cDNA ones, suggesting the preferential expression of mutation-free rDNA units carrying this ITS2 haplotype. These results indicate that the ITS2 region of rDNA is far from complete homogenization in this species, and that the different rDNA units are not expressed at random, with some of them being severely downregulated. © 2015 The Royal Entomological Society.

  10. Theory and implementation of a very high throughput true random number generator in field programmable gate array.

    Science.gov (United States)

    Wang, Yonggang; Hui, Cong; Liu, Chong; Xu, Chao

    2016-04-01

    The contribution of this paper is proposing a new entropy extraction mechanism based on sampling phase jitter in ring oscillators to make a high throughput true random number generator in a field programmable gate array (FPGA) practical. Starting from experimental observation and analysis of the entropy source in FPGA, a multi-phase sampling method is exploited to harvest the clock jitter with a maximum entropy and fast sampling speed. This parametrized design is implemented in a Xilinx Artix-7 FPGA, where the carry chains in the FPGA are explored to realize the precise phase shifting. The generator circuit is simple and resource-saving, so that multiple generation channels can run in parallel to scale the output throughput for specific applications. The prototype integrates 64 circuit units in the FPGA to provide a total output throughput of 7.68 Gbps, which meets the requirement of current high-speed quantum key distribution systems. The randomness evaluation, as well as its robustness to ambient temperature, confirms that the new method in a purely digital fashion can provide high-speed high-quality random bit sequences for a variety of embedded applications.

  11. Computational methods for detecting copy number variations in cancer genome using next generation sequencing: principles and challenges

    Science.gov (United States)

    Liu, Biao; Morrison, Carl D.; Johnson, Candace S.; Trump, Donald L.; Qin, Maochun; Conroy, Jeffrey C.; Wang, Jianmin; Liu, Song

    2013-01-01

    Accurate detection of somatic copy number variations (CNVs) is an essential part of cancer genome analysis, and plays an important role in oncotarget identifications. Next generation sequencing (NGS) holds the promise to revolutionize somatic CNV detection. In this review, we provide an overview of current analytic tools used for CNV detection in NGS-based cancer studies. We summarize the NGS data types used for CNV detection, decipher the principles for data preprocessing, segmentation, and interpretation, and discuss the challenges in somatic CNV detection. This review aims to provide a guide to the analytic tools used in NGS-based cancer CNV studies, and to discuss the important factors that researchers need to consider when analyzing NGS data for somatic CNV detections. PMID:24240121

  12. Next-Generation Sequencing-Based Detection of Germline Copy Number Variations in BRCA1/BRCA2

    DEFF Research Database (Denmark)

    Schmidt, Ane Y; Hansen, Thomas V O; Ahlborn, Lise B

    2017-01-01

    identified by MLPA in 48 Danish breast and/or ovarian cancer families were analyzed. Moreover, 120 patient samples previously determined as negative for BRCA1/BRCA2 CNVs by MLPA were included in the analysis. Comparison of the NGS data with the data from MLPA revealed that the sensitivity was 100%, whereas......Genetic testing of BRCA1/2 includes screening for single nucleotide variants and small insertions/deletions and for larger copy number variations (CNVs), primarily by Sanger sequencing and multiplex ligation-dependent probe amplification (MLPA). With the advent of next-generation sequencing (NGS...... the specificity was 95%. Taken together, this study validates a one-step bioinformatics work-flow to call germline BRCA1/2 CNVs using data obtained by NGS of a breast cancer gene panel. The work-flow represents a robust and easy-to-use method for full BRCA1/2 screening, which can be easily implemented in routine...

  13. An unconventional approach to impedance microbiology: detection of culture media conductivity variations due to bacteriophage generated lyses of host bacteria.

    Science.gov (United States)

    Mortari, Alessia; Adami, Andrea; Lorenzelli, Leandro

    2015-05-15

    A novel and unconventional approach to impedance microbiology has been under investigation. In our approach, solution conductivity variations are generated from bacteriophage lyses of infected host cells and the consequent release of conductive endoplasmic material. To sensitively detect the lysis, low conductive growth media have been developed. A microchip has been fabricated to perform the analysis. The microchip is made of two bare gold electrodes and PDMS microchamber of 36 nL volume. Escherichia coli and selective phages T4 have been used as case study. Proof-of-principle experiments are here presented and discussed. The method was characterised in a wide range between 10(4) and 10(8) CFU/mL, where linear relation was found between conductivity variation and cell concentration in a log10 vs. log10 plot. The method is suited to integration with sample preparation based on phage-functionalised magnetic beads. It has a potential detection limit below 1 CFU/chamber and a total assay time of less than 1 h. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Using histograms to introduce randomization in the generation of ensembles of decision trees

    Science.gov (United States)

    Kamath, Chandrika; Cantu-Paz, Erick; Littau, David

    2005-02-22

    A system for decision tree ensembles that includes a module to read the data, a module to create a histogram, a module to evaluate a potential split according to some criterion using the histogram, a module to select a split point randomly in an interval around the best split, a module to split the data, and a module to combine multiple decision trees in ensembles. The decision tree method includes the steps of reading the data; creating a histogram; evaluating a potential split according to some criterion using the histogram, selecting a split point randomly in an interval around the best split, splitting the data, and combining multiple decision trees in ensembles.

  15. Generating Variable and Random Schedules of Reinforcement Using Microsoft Excel Macros

    Science.gov (United States)

    Bancroft, Stacie L.; Bourret, Jason C.

    2008-01-01

    Variable reinforcement schedules are used to arrange the availability of reinforcement following varying response ratios or intervals of time. Random reinforcement schedules are subtypes of variable reinforcement schedules that can be used to arrange the availability of reinforcement at a constant probability across number of responses or time.…

  16. Heuristic Relative Entropy Principles with Complex Measures: Large-Degree Asymptotics of a Family of Multi-variate Normal Random Polynomials

    Science.gov (United States)

    Kiessling, Michael Karl-Heinz

    2017-10-01

    Let z\\in C, let σ ^2>0 be a variance, and for N\\in N define the integrals E_N^{}(z;σ ) := {1/σ } \\int _R\\ (x^2+z^2) e^{-{1/2σ^2 x^2}}{√{2π }}/dx \\quad if N=1, {1/σ } \\int _{R^N} \\prod \\prod \\limits _{1≤ k1. These are expected values of the polynomials P_N^{}(z)=\\prod _{1≤ n≤ N}(X_n^2+z^2) whose 2 N zeros ± i X_k^{}_{k=1,\\ldots ,N} are generated by N identically distributed multi-variate mean-zero normal random variables {X_k}N_{k=1} with co-variance {Cov}_N^{}(X_k,X_l)=(1+σ ^2-1/N)δ _{k,l}+σ ^2-1/N(1-δ _{k,l}). The E_N^{}(z;σ ) are polynomials in z^2, explicitly computable for arbitrary N, yet a list of the first three E_N^{}(z;σ ) shows that the expressions become unwieldy already for moderate N—unless σ = 1, in which case E_N^{}(z;1) = (1+z^2)^N for all z\\in C and N\\in N. (Incidentally, commonly available computer algebra evaluates the integrals E_N^{}(z;σ ) only for N up to a dozen, due to memory constraints). Asymptotic evaluations are needed for the large- N regime. For general complex z these have traditionally been limited to analytic expansion techniques; several rigorous results are proved for complex z near 0. Yet if z\\in R one can also compute this "infinite-degree" limit with the help of the familiar relative entropy principle for probability measures; a rigorous proof of this fact is supplied. Computer algebra-generated evidence is presented in support of a conjecture that a generalization of the relative entropy principle to signed or complex measures governs the N→ ∞ asymptotics of the regime iz\\in R. Potential generalizations, in particular to point vortex ensembles and the prescribed Gauss curvature problem, and to random matrix ensembles, are emphasized.

  17. A randomized controlled trial of an inference generation strategy intervention for adults with high-functioning autism spectrum disorder.

    Science.gov (United States)

    Murza, Kimberly A; Nye, Chad; Schwartz, Jamie B; Ehren, Barbara J; Hahs-Vaughn, Debbie L

    2014-08-01

    The present intervention study investigated the efficacy of the ACT & Check Strategy intervention to improve inference generation when reading, metacognitive ability, general reading comprehension, and social inference ability in adults with high-functioning autism spectrum disorder (HF-ASD). Twenty-five adults with HF-ASD were randomly assigned to either a treatment or a control group. Treatment sessions were conducted in 1-hr sessions, twice a week, for a total of 6 weeks. Treatment focused on explicit instruction of components of inference generation, categories of inferences, and increasingly independent strategy use. The treatment group demonstrated significantly superior performance on 1 of 2 measures of inference generation in reading and 1 measure of metacognitive ability compared with the control group. Significant differences between groups were not found on measures of reading comprehension or social inference ability. These findings suggest that the ACT & Check Strategy was effective in improving participants' ability to generate inferences in reading and certain metacognitive abilities, but the skills do not appear to generalize to other social communication contexts, such as social inference generation. This research provides a measure of support for explicitly teaching inference generation to address a reading inference deficit in adults with HF-ASD.

  18. Mersenne Twister: A 623-Dimensionally Equidistributed Uniform Pseudo-Random Number Generator

    OpenAIRE

    Matsumoto, Makoto; Nishimura, Takuji

    1998-01-01

    A new algorithm called Mersenne Twister (MT) is proposed for generating uniform pseudorandom numbers. For a particular choice of parameters, the algorithm provides a super astronomical period of 219937 - 1 and 623-dimensional equidistribution up to 32-bit accuracy, while using a working area of only 624 words. This is a new variant of the previously proposed generators, TGFSR, modified so as to admit a Mersenne-prime period. The characteristic polynomial has many terms. The distribution up to...

  19. Pseudorandom Number Generators for Mobile Devices: An Examination and Attempt to Improve Randomness

    Science.gov (United States)

    2013-09-01

    what if the tickets are not properly mixed and instead are just put in a jar as they are being sold? What if the lottery tickets have different sizes...winner of the raffle randomly, and the lottery would not be considered fair. In the situation described in the previous paragraph, the raffle...official drawing the winning ticket is clearly a great risk to biasing the outcome. Therefore, mechanical raffle and lottery machines are widely used in

  20. Pseudo-Random Modulation of a Laser Diode for Generating Ultrasonic Longitudinal Waves

    Science.gov (United States)

    Madaras, Eric I.; Anatasi, Robert F.

    2004-01-01

    Laser generated ultrasound systems have historically been more complicated and expensive than conventional piezoelectric based systems, and this fact has relegated the acceptance of laser based systems to niche applications for which piezoelectric based systems are less suitable. Lowering system costs, while improving throughput, increasing ultrasound signal levels, and improving signal-to-noise are goals which will help increase the general acceptance of laser based ultrasound. One current limitation with conventional laser generated ultrasound is a material s damage threshold limit. Increasing the optical power to generate more signal eventually damages the material being tested due to rapid, high heating. Generation limitations for laser based ultrasound suggests the use of pulse modulation techniques as an alternate generation method. Pulse modulation techniques can spread the laser energy over time or space, thus reducing laser power densities and minimizing damage. Previous experiments by various organizations using spatial or temporal pulse modulation have been shown to generate detectable surface, plate, and bulk ultrasonic waves with narrow frequency bandwidths . Using narrow frequency bandwidths improved signal detectability, but required the use of expensive and powerful lasers and opto-electronic systems. The use of a laser diode to generate ultrasound is attractive because of its low cost, small size, light weight, simple optics and modulation capability. The use of pulse compression techniques should allow certain types of laser diodes to produce usable ultrasonic signals. The method also does not need to be limited to narrow frequency bandwidths. The method demonstrated here uses a low power laser diode (approximately 150 mW) that is modulated by controlling the diode s drive current and the resulting signal is recovered by cross correlation. A potential application for this system which is briefly demonstrated is in detecting signals in thick

  1. Experimental observation of second-harmonic generation and diffusion inside random media

    NARCIS (Netherlands)

    Faez, Sanli; Johnson, P. M.; Mazurenko, D. A.; Lagendijk, Ad

    We have experimentally measured the distribution of the second-harmonic intensity that is generated inside a highly scattering slab of porous gallium phosphide. Two complementary techniques for determining the distribution are used. First, the spatial distribution of second-harmonic light intensity

  2. Simulated Performance Evaluation of a Selective Tracker Through Random Scenario Generation

    DEFF Research Database (Denmark)

    Hussain, Dil Muhammad Akbar

    2006-01-01

      The paper presents a simulation study on the performance of a target tracker using selective track splitting filter algorithm through a random scenario implemented on a digital signal processor.  In a typical track splitting filter all the observation which fall inside a likelihood ellipse...... are used for update, however, in our proposed selective track splitting filter less number of observations are used for track update.  Much of the previous performance work [1] has been done on specific (deterministic) scenarios. One of the reasons for considering the specific scenarios, which were...

  3. The isector: a simple and direct method for generating isotropic, uniform random sections from small specimens

    DEFF Research Database (Denmark)

    Nyengaard, Jens Randel; Gundersen, Hans Jørgen Gottlieb

    1992-01-01

    The very simple and strong principle of vertical sections devised by Baddeley et al. has been a major advance in stereology when any kind of anisotropy is present in the specimen under study. On the other hand, some important stereological estimators still require isotropic, uniform random sectio....... This paper deals with a simple technique for embedding specimens in rubber moulds with spherical cavities. After the embedding, any handling or the resulting sphere independent of the specimen will induce isotropy of the final histological sections....

  4. Can Targeted Intervention Mitigate Early Emotional and Behavioral Problems?: Generating Robust Evidence within Randomized Controlled Trials.

    Directory of Open Access Journals (Sweden)

    Orla Doyle

    Full Text Available This study examined the impact of a targeted Irish early intervention program on children's emotional and behavioral development using multiple methods to test the robustness of the results. Data on 164 Preparing for Life participants who were randomly assigned into an intervention group, involving home visits from pregnancy onwards, or a control group, was used to test the impact of the intervention on Child Behavior Checklist scores at 24-months. Using inverse probability weighting to account for differential attrition, permutation testing to address small sample size, and quantile regression to characterize the distributional impact of the intervention, we found that the few treatment effects were largely concentrated among boys most at risk of developing emotional and behavioral problems. The average treatment effect identified a 13% reduction in the likelihood of falling into the borderline clinical threshold for Total Problems. The interaction and subgroup analysis found that this main effect was driven by boys. The distributional analysis identified a 10-point reduction in the Externalizing Problems score for boys at the 90th percentile. No effects were observed for girls or for the continuous measures of Total, Internalizing, and Externalizing problems. These findings suggest that the impact of this prenatally commencing home visiting program may be limited to boys experiencing the most difficulties. Further adoption of the statistical methods applied here may help to improve the internal validity of randomized controlled trials and contribute to the field of evaluation science more generally.ISRCTN Registry ISRCTN04631728.

  5. Internal wave generation by tidal flow over periodically and randomly distributed seamounts

    Science.gov (United States)

    Zhang, Likun; Buijsman, Maarten C.; Comino, Eva; Swinney, Harry L.

    2017-06-01

    We examine numerically the conversion of barotropic tidal energy into internal waves by flow over an isolated seamount and over systems of periodically and randomly distributed 1100 m tall seamounts with Gaussian profiles. The simulations use the Massachusetts Institute of Technology general circulation model (MITgcm) to calculate for an infinitely deep ocean the dependence of the energy conversion on seamount slope, seamount separation, tidal direction, and the size and aspect ratio of the simulation domain. For neighboring seamounts with a slope greater than the internal wave beam slope, wave interference reduces the conversion relative to that calculated for an isolated seamount, and relative to that predicted by linear theory for a seamount of slope less than the beam slope. The conversion by an individual seamount in a system of random seamounts separated by an average distance of 18 km is found to be suppressed by 16% relative to the conversion by an isolated seamount. This study provides insight into tidal conversion by ocean seamounts modeled as Gaussian mountains with slopes both smaller and larger than the beam slope. We conclude that the total energy conversion by all seamounts (peak height ≥1000 m) and knolls (peak height 500-1000 m), taking into account interference affects, is of the order of 1% of the total barotropic to baroclinic energy conversion in the oceans, which is about twice as large as previous estimates.

  6. Synaptic signal streams generated by ex vivo neuronal networks contain non-random, complex patterns.

    Science.gov (United States)

    Lee, Sangmook; Zemianek, Jill M; Shultz, Abraham; Vo, Anh; Maron, Ben Y; Therrien, Mikaela; Courtright, Christina; Guaraldi, Mary; Yanco, Holly A; Shea, Thomas B

    2014-11-01

    Cultured embryonic neurons develop functional networks that transmit synaptic signals over multiple sequentially connected neurons as revealed by multi-electrode arrays (MEAs) embedded within the culture dish. Signal streams of ex vivo networks contain spikes and bursts of varying amplitude and duration. Despite the random interactions inherent in dissociated cultures, neurons are capable of establishing functional ex vivo networks that transmit signals among synaptically connected neurons, undergo developmental maturation, and respond to exogenous stimulation by alterations in signal patterns. These characteristics indicate that a considerable degree of organization is an inherent property of neurons. We demonstrate herein that (1) certain signal types occur more frequently than others, (2) the predominant signal types change during and following maturation, (3) signal predominance is dependent upon inhibitory activity, and (4) certain signals preferentially follow others in a non-reciprocal manner. These findings indicate that the elaboration of complex signal streams comprised of a non-random distribution of signal patterns is an emergent property of ex vivo neuronal networks. Copyright © 2014. Published by Elsevier Ltd.

  7. Highly efficient hybrid energy generator: coupled organic photovoltaic device and randomly oriented electrospun poly(vinylidene fluoride) nanofiber.

    Science.gov (United States)

    Park, Boongik; Lee, Kihwan; Park, Jongjin; Kim, Jongmin; Kim, Ohyun

    2013-03-01

    A hybrid architecture consisting of an inverted organic photovoltaic device and a randomly-oriented electrospun PVDF piezoelectric device was fabricated as a highly-efficient energy generator. It uses the inverted photovoltaic device with coupled electrospun PVDF nanofibers as tandem structure to convert solar and mechanical vibrations energy to electricity simultaneously or individually. The power conversion efficiency of the photovoltaic device was also significantly improved up to 4.72% by optimized processes such as intrinsic ZnO, MoO3 and active layer. A simple electrospinning method with the two electrode technique was adopted to achieve a high voltage of - 300 mV in PVDF piezoelectric fibers. Highly-efficient HEG using voltage adder circuit provides the conceptual possibility of realizing multi-functional energy generator whenever and wherever various energy sources are available.

  8. Simultaneous Detection of Both Single Nucleotide Variations and Copy Number Alterations by Next-Generation Sequencing in Gorlin Syndrome.

    Directory of Open Access Journals (Sweden)

    Kei-ichi Morita

    Full Text Available Gorlin syndrome (GS is an autosomal dominant disorder that predisposes affected individuals to developmental defects and tumorigenesis, and caused mainly by heterozygous germline PTCH1 mutations. Despite exhaustive analysis, PTCH1 mutations are often unidentifiable in some patients; the failure to detect mutations is presumably because of mutations occurred in other causative genes or outside of analyzed regions of PTCH1, or copy number alterations (CNAs. In this study, we subjected a cohort of GS-affected individuals from six unrelated families to next-generation sequencing (NGS analysis for the combined screening of causative alterations in Hedgehog signaling pathway-related genes. Specific single nucleotide variations (SNVs of PTCH1 causing inferred amino acid changes were identified in four families (seven affected individuals, whereas CNAs within or around PTCH1 were found in two families in whom possible causative SNVs were not detected. Through a targeted resequencing of all coding exons, as well as simultaneous evaluation of copy number status using the alignment map files obtained via NGS, we found that GS phenotypes could be explained by PTCH1 mutations or deletions in all affected patients. Because it is advisable to evaluate CNAs of candidate causative genes in point mutation-negative cases, NGS methodology appears to be useful for improving molecular diagnosis through the simultaneous detection of both SNVs and CNAs in the targeted genes/regions.

  9. Genome evolution is driven by gene expression-generated biophysical constraints through RNA-directed genetic variation: A hypothesis.

    Science.gov (United States)

    Auboeuf, Didier

    2017-10-01

    The biogenesis of RNAs and proteins is a threat to the cell. Indeed, the act of transcription and nascent RNAs challenge DNA stability. Both RNAs and nascent proteins can also initiate the formation of toxic aggregates because of their physicochemical properties. In reviewing the literature, I show that co-transcriptional and co-translational biophysical constraints can trigger DNA instability that in turn increases the likelihood that sequences that alleviate the constraints emerge over evolutionary time. These directed genetic variations rely on the biogenesis of small RNAs that are transcribed directly from challenged DNA regions or processed from the transcripts that directly or indirectly generate constraints or aggregates. These small RNAs can then target the genomic regions from which they initially originate and increase the local mutation rate of the targeted loci. This mechanism is based on molecular pathways involved in anti-parasite genome defence systems, and implies that gene expression-related biophysical constraints represent a driving force of genome evolution. © 2017 The Authors. BioEssays Published by Wiley Periodicals, Inc.

  10. Experimental Investigation of Micrometer Scale Areal Density Variations in Metal Liners Driven by the 1 MA COBRA Pulsed Power Generator

    Science.gov (United States)

    Atoyan, Levon; Pikuz, Sergei; Shelkovenko, Tania; Hammer, David; Byvank, Tom

    2017-10-01

    On the 20 MA Z machine, the seed for the MRT instability was mitigated in the Magnetized Liner Inertial Fusion experiment using a thick dielectric coating. We have used high-resolution radiography to study the development of small-scale ( 10-30 μm) features in thin foils on the 1 MA, 100-200 ns COBRA pulsed power generator. We examined those features quantitatively in a 16 µm thick cylindrical Al liner, where we show areal density variation of up to 40-50%. We then show how the features' wavelength decreases when the material is changed from Al to Ni, Cu, and Ti, going from 21 +/-4 µm for Al to 11 +/-2 µm for Ti. Moreover, we show that expansion inhibition on both sides by dielectric material reduces small-scale feature size and density, and we show how pattern seeding can affect those parameters. This work is supported by the National Nuclear Security Administration Stewardship Sciences Academic Programs under Department of Energy Cooperative Agreement DE-NA0001836 as well as by the Department of Energy Grant Number DE-NA0002952.

  11. ANALYSIS AND VALIDATION OF GRID DEM GENERATION BASED ON GAUSSIAN MARKOV RANDOM FIELD

    Directory of Open Access Journals (Sweden)

    F. J. Aguilar

    2016-06-01

    Full Text Available Digital Elevation Models (DEMs are considered as one of the most relevant geospatial data to carry out land-cover and land-use classification. This work deals with the application of a mathematical framework based on a Gaussian Markov Random Field (GMRF to interpolate grid DEMs from scattered elevation data. The performance of the GMRF interpolation model was tested on a set of LiDAR data (0.87 points/m2 provided by the Spanish Government (PNOA Programme over a complex working area mainly covered by greenhouses in Almería, Spain. The original LiDAR data was decimated by randomly removing different fractions of the original points (from 10% to up to 99% of points removed. In every case, the remaining points (scattered observed points were used to obtain a 1 m grid spacing GMRF-interpolated Digital Surface Model (DSM whose accuracy was assessed by means of the set of previously extracted checkpoints. The GMRF accuracy results were compared with those provided by the widely known Triangulation with Linear Interpolation (TLI. Finally, the GMRF method was applied to a real-world case consisting of filling the LiDAR-derived DSM gaps after manually filtering out non-ground points to obtain a Digital Terrain Model (DTM. Regarding accuracy, both GMRF and TLI produced visually pleasing and similar results in terms of vertical accuracy. As an added bonus, the GMRF mathematical framework makes possible to both retrieve the estimated uncertainty for every interpolated elevation point (the DEM uncertainty and include break lines or terrain discontinuities between adjacent cells to produce higher quality DTMs.

  12. W-Band Millimeter-Wave Vector Signal Generation Based on Precoding-Assisted Random Photonic Frequency Tripling Scheme Enabled by Phase Modulator

    National Research Council Canada - National Science Library

    Li, Xinying; Xu, Yuming; Xiao, Jiangnan; Yu, Jianjun

    2016-01-01

    We propose W-band photonic millimeter-wave (mm-wave) vector signal generation employing a precoding-assisted random frequency tripling scheme enabled by a single phase modulator cascaded with a wavelength selective switch (WSS...

  13. Quantum random number generator based on ‘Fermi–Dirac’ statistics of photocounts of faint laser pulses with a 75 Mbit s‑1 rate

    Science.gov (United States)

    Balygin, K. A.; Zaitsev, V. I.; Klimov, A. N.; Kulik, S. P.; Molotkov, S. N.; Popova, E.; Vinogradov, S.

    2017-12-01

    We implemented experimentally a quantum random number generator, based on the registration of quasi-single-photon light by a silicon photo-multiplier, which allows one to reliably achieve the Poisson statistics of photocounts. The use of the optimal grouping of photocounts and a polynomial-length sequence of the method for extracting the random sequence 0 and 1 made it possible to achieve the output rate of a provably random sequence up to 75 Mbit s-1 .

  14. Random Forests Are Able to Identify Differences in Clotting Dynamics from Kinetic Models of Thrombin Generation.

    Directory of Open Access Journals (Sweden)

    Jayavel Arumugam

    Full Text Available Current methods for distinguishing acute coronary syndromes such as heart attack from stable coronary artery disease, based on the kinetics of thrombin formation, have been limited to evaluating sensitivity of well-established chemical species (e.g., thrombin using simple quantifiers of their concentration profiles (e.g., maximum level of thrombin concentration, area under the thrombin concentration versus time curve. In order to get an improved classifier, we use a 34-protein factor clotting cascade model and convert the simulation data into a high-dimensional representation (about 19000 features using a piecewise cubic polynomial fit. Then, we systematically find plausible assays to effectively gauge changes in acute coronary syndrome/coronary artery disease populations by introducing a statistical learning technique called Random Forests. We find that differences associated with acute coronary syndromes emerge in combinations of a handful of features. For instance, concentrations of 3 chemical species, namely, active alpha-thrombin, tissue factor-factor VIIa-factor Xa ternary complex, and intrinsic tenase complex with factor X, at specific time windows, could be used to classify acute coronary syndromes to an accuracy of about 87.2%. Such a combination could be used to efficiently assay the coagulation system.

  15. Within- and Trans-Generational Effects of Variation in Dietary Macronutrient Content on Life-History Traits in the Moth Plodia interpunctella.

    Science.gov (United States)

    Littlefair, Joanne E; Knell, Robert J

    2016-01-01

    It is increasingly clear that parental environment can play an important role in determining offspring phenotype. These "transgenerational effects" have been linked to many different components of the environment, including toxin exposure, infection with pathogens and parasites, temperature and food quality. In this study, we focus on the latter, asking how variation in the quantity and quality of nutrition affects future generations. Previous studies have shown that artificial diets are a useful tool to examine the within-generation effects of variation in macronutrient content on life history traits, and could therefore be applied to investigations of the transgenerational effects of parental diet. Synthetic diets varying in total macronutrient content and protein: carbohydrate ratios were used to examine both within- and trans-generational effects on life history traits in a generalist stored product pest, the Indian meal moth Plodia interpunctella. The macronutrient composition of the diet was important for shaping within-generation life history traits, including pupal weight, adult weight, and phenoloxidase activity, and had indirect effects via maternal weight on fecundity. Despite these clear within-generation effects on the biology of P. interpunctella, diet composition had no transgenerational effects on the life history traits of offspring. P. interpunctella mothers were able to maintain their offspring quality, possibly at the expense of their own somatic condition, despite high variation in dietary macronutrient composition. This has important implications for the plastic biology of this successful generalist pest.

  16. Within- and Trans-Generational Effects of Variation in Dietary Macronutrient Content on Life-History Traits in the Moth Plodia interpunctella.

    Directory of Open Access Journals (Sweden)

    Joanne E Littlefair

    Full Text Available It is increasingly clear that parental environment can play an important role in determining offspring phenotype. These "transgenerational effects" have been linked to many different components of the environment, including toxin exposure, infection with pathogens and parasites, temperature and food quality. In this study, we focus on the latter, asking how variation in the quantity and quality of nutrition affects future generations. Previous studies have shown that artificial diets are a useful tool to examine the within-generation effects of variation in macronutrient content on life history traits, and could therefore be applied to investigations of the transgenerational effects of parental diet. Synthetic diets varying in total macronutrient content and protein: carbohydrate ratios were used to examine both within- and trans-generational effects on life history traits in a generalist stored product pest, the Indian meal moth Plodia interpunctella. The macronutrient composition of the diet was important for shaping within-generation life history traits, including pupal weight, adult weight, and phenoloxidase activity, and had indirect effects via maternal weight on fecundity. Despite these clear within-generation effects on the biology of P. interpunctella, diet composition had no transgenerational effects on the life history traits of offspring. P. interpunctella mothers were able to maintain their offspring quality, possibly at the expense of their own somatic condition, despite high variation in dietary macronutrient composition. This has important implications for the plastic biology of this successful generalist pest.

  17. Efficacy of micronutrient supplementation on skin aging and seasonal variation: a randomized, placebo-controlled, double-blind study

    Directory of Open Access Journals (Sweden)

    Fanian F

    2013-11-01

    Full Text Available Ferial Fanian,1,2 Sophie Mac-Mary,3 Adeline Jeudy,1,2 Thomas Lihoreau,1,2 Rafat Messikh,1,2 Jean-Paul Ortonne,4 Jean-Marie Sainthillier,3 Ahmed Elkhyat,1,2 Alexandre Guichard,1,2 Kamran Hejazi Kenari,1,2 Philippe Humbert1,2,5,61Center for Studies and Research on the Integument (CERT, Department of Dermatology, University Hospital of Besançon, Besançon, France; 2Clinical Investigation Center, CIC-BT 506, CHRU Besançon, France; 3SKINEXIGENCE, University Hospital of Jean Minjoz, Besançon, France; 4Department of Dermatology, University Hospital of L'archet, Nice, France; 5University of Franche-Comté, Besançon, France; 6INSERM 1098, Structure Fédérative de Recherche, Besançon, FranceBackground: Several studies have confirmed dramatic changes in skin surface parameters during the winter months. Although there are many studies supporting the positive effects of topical treatment, there are no published studies demonstrating the effects of oral supplementation in the prevention of negative skin changes during winter. The purpose of this study was to evaluate the efficacy of an oral micronutrient supplement in preventing the negative effects of winter weather on skin quality using noninvasive biometrologic instruments.Methods: This study included 80 healthy female volunteers aged 35–55 years with phototype II–IV skin. Randomization was balanced. Two tablets of a micronutrient supplement (Perfectil® Platinum or placebo were administered once daily for 4 months. The volunteers were examined at baseline, after 4 months, and 6 weeks after termination of treatment (month 5.5. The evaluation included skin microrelief by Visioscan® as the main outcome, and the secondary outcomes were results on standard macrophotography, skin tension by Reviscometer®, skin high-frequency ultrasound, and self-assessment.Results: For all pseudoroughness and microrelief indicators, there was a significant increase from baseline to month 4 in the placebo group (P<0

  18. Benefits of Reiki therapy for a severely neutropenic patient with associated influences on a true random number generator.

    Science.gov (United States)

    Morse, Melvin L; Beem, Lance W

    2011-12-01

    Reiki therapy is documented for relief of pain and stress. Energetic healing has been documented to alter biologic markers of illness such as hematocrit. True random number generators are reported to be affected by energy healers and spiritually oriented conscious awareness. The patient was a then 54-year-old severely ill man who had hepatitis C types 1 and 2 and who did not improve with conventional therapy. He also suffered from obesity, the metabolic syndrome, asthma, and hypertension. He was treated with experimental high-dose interferon/riboviron therapy with resultant profound anemia and neutropenia. Energetic healing and Reiki therapy was administered initially to enhance the patient's sense of well-being and to relieve anxiety. Possible effects on the patient's absolute neutrophil count and hematocrit were incidentally noted. Reiki therapy was then initiated at times of profound neutropenia to assess its possible effect on the patient's absolute neutrophil count (ANC). Reiki and other energetic healing sessions were monitored with a true random number generator (RNG). Statistically significant relationships were documented between Reiki therapy, a quieting of the electronically created white noise of the RNG during healing sessions, and improvement in the patient's ANC. The immediate clinical result was that the patient could tolerate the high-dose interferon regimen without missing doses because of absolute neutropenia. The patient was initially a late responder to interferon and had been given a 5% chance of clearing the virus. He remains clear of the virus 1 year after treatment. The association between changes in the RNG, Reiki therapy, and a patient's ANC is the first to the authors' knowledge in the medical literature. Future studies assessing the effects of energetic healing on specific biologic markers of disease are anticipated. Concurrent use of a true RNG may prove to correlate with the effectiveness of energetic therapy.

  19. A time-series approach to random number generation: Using recurrence quantification analysis to capture executive behavior

    Directory of Open Access Journals (Sweden)

    Wouter eOomens

    2015-06-01

    Full Text Available The concept of executive functions plays a prominent role in contemporary experimental and clinical studies on cognition. One paradigm used in this framework is the random number generation (RNG task, the execution of which demands aspects of executive functioning, specifically inhibition and working memory. Data from the RNG task are best seen as a series of successive events. However, traditional RNG measures that are used to quantify executive functioning are mostly summary statistics referring to deviations from mathematical randomness. In the current study, we explore the utility of recurrence quantification analysis (RQA, a nonlinear method that keeps the entire sequence intact, as a better way to describe executive functioning compared to traditional measures. To this aim, 242 first- and second-year students completed a non-paced RNG task. Principal component analysis of their data showed that traditional and RQA measures convey more or less the same information. However, RQA measures do so more parsimoniously and have a better interpretation.

  20. Second harmonic generation in gallium phosphide microdisks on silicon: from strict \\bar{4} to random quasi-phase matching

    Science.gov (United States)

    Guillemé, P.; Dumeige, Y.; Stodolna, J.; Vallet, M.; Rohel, T.; Létoublon, A.; Cornet, C.; Ponchet, A.; Durand, O.; Léger, Y.

    2017-06-01

    The convergence of nonlinear optical devices and silicon photonics is a key milestone for the practical development of photonic integrated circuits. The associated technological issues often stem from material incompatibility. This is the case of second order nonlinear processes in monolithically integrated III-V semiconductor devices on silicon, where structural defects called antiphase domains strongly impact the optical properties of the material. We theoretically investigate the influence of antiphase domains on second harmonic generation in III-V whispering gallery mode microresonators on silicon and focus on the effects of the antiphase domains’ mean size (i.e. the correlation length of the distribution). We demonstrate that the domain distributions can have opposite effects depending on the nonlinear process under consideration: while antiphase domains negatively impact second harmonic generation under \\bar{4} quasi-phase matching conditions (independent of the correlation length), large conversion efficiencies can arise far from \\bar{4}-quasi-phase matching provided that the APD correlation length remains within an appropriate range, and is still compatible with the spontaneous emergence of such defects in the usual III-V on Si epilayers. Such a build-up can be explained by the occurrence of random quasi-phase matching in the system.

  1. Next-generation sequencing approaches in genetic rodent model systems to study functional effects of human genetic variation.

    NARCIS (Netherlands)

    Guryev, V.; Cuppen, E.

    2009-01-01

    Rapid advances in DNA sequencing improve existing techniques and enable new approaches in genetics and functional genomics, bringing about unprecedented coverage, resolution and sensitivity. Enhanced toolsets can facilitate the untangling of connections between genomic variation, environmental

  2. Next-generation sequencing approaches in genetic rodent model systems to study functional effects of human genetic variation

    NARCIS (Netherlands)

    Guryev, Victor; Cuppen, Edwin

    2009-01-01

    Rapid advances in DNA sequencing improve existing techniques and enable new approaches in genetics and functional genomics, bringing about unprecedented coverage, resolution and sensitivity. Enhanced toolsets can facilitate the untangling of connections between genomic variation, environmental

  3. Sleep quality and body composition variations in obese male adults after 14 weeks of yoga intervention: A randomized controlled trial

    OpenAIRE

    P B Rshikesan; Pailoor Subramanya; Deepeshwar Singh

    2017-01-01

    Background: Obesity is a big challenge all over the world. It is associated with many noncommunicable diseases. Yoga known to be add-on treatment may be effective for obesity control. Aim: To assess the effect of integrated approach of yoga therapy (IAYT) for body composition and quality of sleep in adult obese male. Subjects and Methods: A randomized controlled trial was conducted for 14 weeks on obese male of urban setting. Eighty individuals were randomly divided into two groups, i.e., yog...

  4. An empirical test of pseudo random number generators by means of an exponential decaying process; Una prueba empirica de generadores de numeros pseudoaleatorios mediante un proceso de decaimiento exponencial

    Energy Technology Data Exchange (ETDEWEB)

    Coronel B, H.F.; Hernandez M, A.R.; Jimenez M, M.A. [Facultad de Fisica e Inteligencia Artificial, Universidad Veracruzana, A.P. 475, Xalapa, Veracruz (Mexico); Mora F, L.E. [CIMAT, A.P. 402, 36000 Guanajuato (Mexico)]. e-mail: hcoronel@uv.mx

    2007-07-01

    Empirical tests for pseudo random number generators based on the use of processes or physical models have been successfully used and are considered as complementary to theoretical tests of randomness. In this work a statistical methodology for evaluating the quality of pseudo random number generators is presented. The method is illustrated in the context of the so-called exponential decay process, using some pseudo random number generators commonly used in physics. (Author)

  5. Random within-herd variation in financial performance and time to financial steady-state following management changes in the dairy herd

    DEFF Research Database (Denmark)

    Kristensen, Erling Lundager; Østergaard, Søren; Krogh, Mogens Agerbo

    2008-01-01

    The manager of a dairy herd and the affiliated consultants constantly need to judge whether financial performance of the production system is satisfactory and whether financial performance relates to real (systematic) effects of changes in management. This is no easy task because the dairy herd...... is a very complex system. Thus, it is difficult to obtain empirical data that allows a valid estimation of the random (within-herd) variation in financial performance corrected for management changes. Thus, simulation seems to be the only option. This study suggests that much caution must be recommended...... when claming effect of changes in herd management because the link between management changes (cause) and effect (measured as improvement of gross margin per cow year) is extensively blurred by a large within-herd variation in available real life accounting data and differences between herds in time...

  6. Run charts revisited: a simulation study of run chart rules for detection of non-random variation in health care processes.

    Science.gov (United States)

    Anhøj, Jacob; Olesen, Anne Vingaard

    2014-01-01

    A run chart is a line graph of a measure plotted over time with the median as a horizontal line. The main purpose of the run chart is to identify process improvement or degradation, which may be detected by statistical tests for non-random patterns in the data sequence. We studied the sensitivity to shifts and linear drifts in simulated processes using the shift, crossings and trend rules for detecting non-random variation in run charts. The shift and crossings rules are effective in detecting shifts and drifts in process centre over time while keeping the false signal rate constant around 5% and independent of the number of data points in the chart. The trend rule is virtually useless for detection of linear drift over time, the purpose it was intended for.

  7. A Basic Accounting of Variation in Municipal Solid-Waste Generation at the County Level in Texas, 2006: Groundwork for Applying Metabolic-Rift Theory to Waste Generation

    Science.gov (United States)

    Clement, Matthew Thomas

    2009-01-01

    Environmental social scientists debate whether or not modern development reduces society's impact on the biosphere. The empirical research informing the discussion has not yet adequately examined the social determinants of municipal solid-waste (MSW) generation, an increasingly relevant issue, both ecologically and sociologically. A primary…

  8. Critical side channel effects in random bit generation with multiple semiconductor lasers in a polarization-based quantum key distribution system.

    Science.gov (United States)

    Ko, Heasin; Choi, Byung-Seok; Choe, Joong-Seon; Kim, Kap-Joong; Kim, Jong-Hoi; Youn, Chun Ju

    2017-08-21

    Most polarization-based BB84 quantum key distribution (QKD) systems utilize multiple lasers to generate one of four polarization quantum states randomly. However, random bit generation with multiple lasers can potentially open critical side channels that significantly endangers the security of QKD systems. In this paper, we show unnoticed side channels of temporal disparity and intensity fluctuation, which possibly exist in the operation of multiple semiconductor laser diodes. Experimental results show that the side channels can enormously degrade security performance of QKD systems. An important system issue for the improvement of quantum bit error rate (QBER) related with laser driving condition is further addressed with experimental results.

  9. Structural variation in the chicken genome identified by paired-end next-generation DNA sequencing of reduced representation libraries

    NARCIS (Netherlands)

    Kerstens, H.H.D.; Crooijmans, R.P.M.A.; Dibbits, B.W.; Vereijken, A.; Okimoto, R.; Groenen, M.A.M.

    2011-01-01

    Background Variation within individual genomes ranges from single nucleotide polymorphisms (SNPs) to kilobase, and even megabase, sized structural variants (SVs), such as deletions, insertions, inversions, and more complex rearrangements. Although much is known about the extent of SVs in humans and

  10. Ethyl methane sulfonate induced mutations in M2 generation and physiological variations in M1 generation of peppers (Capsicum annuum L.

    Directory of Open Access Journals (Sweden)

    Mohamed Hamed Arisha

    2015-06-01

    Full Text Available This study was conducted to enhance genetic variability in peppers (Capsicum annuum, cv B12 using ethyl methansulphonate (EMS. Exposure to an EMS concentration of 0.6%, v/v for 12 hours was used to mutagenize 2000 seeds for the first generation (M1. It was observed that the growth behaviors including plant height, flowering date and number of seeds per first fruit were different in the M1 generation than in wild type plants. In addition one phenotypic mutation (leaf shape and plant architecture was observed during the M1 generation. During the seedling stage in the M2 generation, the observed changes were in the form of slow growth or chlorophyll defect (e.g., albino, pale green and yellow seedlings. At maturity, there were three kinds of phenotypic mutations observed in three different families of the mutant population. The first observed change was a plant with yellow leaf color, and the leaves of this mutant plant contained 62.19% less chlorophyll a and 64.06% less chlorophyll b as compared to the wild-type. The second mutation resulted in one dwarf plant with a very short stature (6 cm, compact internodes and the leaves and stem were rough and thick. The third type of mutation occurred in four plants and resulted in the leaves of these plants being very thick and longer than those of wild type plants. Furthermore, anatomical observations of the leaf blade section of this mutant plant type contained more xylem and collenchyma tissue in the leaf midrib of the mutant plant than wild type. In addition, its leaf blade contained thicker palisade and spongy tissue than the wild type.

  11. Generation of transgenic mouse line expressing Kusabira Orange throughout body, including erythrocytes, by random segregation of provirus method.

    Science.gov (United States)

    Hamanaka, Sanae; Ooehara, Jun; Morita, Yohei; Ema, Hideo; Takahashi, Satoru; Miyawaki, Atsushi; Otsu, Makoto; Yamaguchi, Tomoyuki; Onodera, Masafumi; Nakauchi, Hiromitsu

    2013-06-14

    Fluorescent-protein transgenic mice are useful for obtaining marked somatic cells to study kinetics of development or differentiation. Fluorescence-marked hematopoietic stem cells in particular are commonly used for studying hematopoiesis. However, as far as we know, no transgenic mouse line is described in which a fluorescent protein is stably and constitutively expressed in all hematopoietic cells, including erythrocytes and platelets. Using the random segregation of provirus (RSP) method, we generated from retrovirally transduced mouse embryonic stem cells a transgenic mouse line expressing a red/orange fluorescent protein, Kusabira Orange (KuO). KuO transgenic mouse line cells carry only one proviral integration site and stably express KuO in all hematopoietic-lineage elements, including erythrocytes and platelets. Moreover, bone-marrow transplantation in KuO transgenic mice demonstrated normal hematopoieisis. KuO transgenic mice likely will prove useful for study of hematopoiesis that includes erythropoiesis and megakaryopoiesis. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Use of Hot Rolling for Generating Low Deviation Twins and a Disconnected Random Boundary Network in Inconel 600 Alloy

    Science.gov (United States)

    Sahu, Sandeep; Yadav, Prabhat Chand; Shekhar, Shashank

    2018-02-01

    In this investigation, Inconel 600 alloy was thermomechanically processed to different strains via hot rolling followed by a short-time annealing treatment to determine an appropriate thermomechanical process to achieve a high fraction of low-Σ CSL boundaries. Experimental results demonstrate that a certain level of deformation is necessary to obtain effective "grain boundary engineering"; i.e., the deformation must be sufficiently high to provide the required driving force for postdeformation static recrystallization, yet it should be low enough to retain a large fraction of original twin boundaries. Samples processed in such a fashion exhibited 77 pct length fraction of low-Σ CSL boundaries, a dominant fraction of which was from Σ3 ( 64 pct), the latter with very low deviation from its theoretical misorientation. The application of hot rolling also resulted in a very low fraction of Σ1 ( 1 pct) boundaries, as desired. The process also leads to so-called "triple junction engineering" with the generation of special triple junctions, which are very effective in disrupting the connectivity of the random grain boundary network.

  13. Use of Hot Rolling for Generating Low Deviation Twins and a Disconnected Random Boundary Network in Inconel 600 Alloy

    Science.gov (United States)

    Sahu, Sandeep; Yadav, Prabhat Chand; Shekhar, Shashank

    2017-12-01

    In this investigation, Inconel 600 alloy was thermomechanically processed to different strains via hot rolling followed by a short-time annealing treatment to determine an appropriate thermomechanical process to achieve a high fraction of low-Σ CSL boundaries. Experimental results demonstrate that a certain level of deformation is necessary to obtain effective "grain boundary engineering"; i.e., the deformation must be sufficiently high to provide the required driving force for postdeformation static recrystallization, yet it should be low enough to retain a large fraction of original twin boundaries. Samples processed in such a fashion exhibited 77 pct length fraction of low-Σ CSL boundaries, a dominant fraction of which was from Σ3 ( 64 pct), the latter with very low deviation from its theoretical misorientation. The application of hot rolling also resulted in a very low fraction of Σ1 ( 1 pct) boundaries, as desired. The process also leads to so-called "triple junction engineering" with the generation of special triple junctions, which are very effective in disrupting the connectivity of the random grain boundary network.

  14. Shopper typologies amongst a Generation Y consumer cohort and variations in terms of age in the fashion apparel market

    National Research Council Canada - National Science Library

    Chengedzai Mafini; Manillall Dhurup; Lawrence Mandhlazi

    2014-01-01

    .... Generation Y consumers have emerged as an important marketing segment. Consequently, a need exists to investigate behavioural issues pertaining to this age cohort on a continuous basis.Methodology...

  15. Variation in the gene frequencies of three generations of humans from Monterrey, Nuevo León, Mexico.

    Science.gov (United States)

    Cerda-Flores, R M; Garza-Chapa, R

    1989-04-01

    Allele frequencies for the ABO, Rh, MNSs, Duffy, Kidd, Lutheran, P and Lewis blood group systems in 207 persons whose 4 grandparents were born in the Monterrey Metropolitan area (MMA), grouped into 3 generations, were ascertained along with other related population from the MMA, Mestizos from Saltillo, Coahuila and Tlaxcala, and from the populations thought to have contributed to their genetic constitution (native Mexican Indians and Spanish). Genetic admixture and distance estimates were calculated. Gene frequencies of the three generations from MMA are intermediate to those of the ancestral populations, indicating that they are Mestizo but with a genetic structure different from Mestizos of Saltillo and Tlaxcala. Both genetic admixture and distance estimates indicate that the oldest generation exhibits the greatest Spanish influence which decreases in the youngest generation and in the other MMA populations as a result of the immigration from the central states of Mexico.

  16. Letter to the editor: Generation of self organized critical connectivity network map (SOCCNM of randomly situated water bodies during flooding process

    Directory of Open Access Journals (Sweden)

    B. S. Daya Sagar

    2001-01-01

    Full Text Available This letter presents a brief framework based on nonlinear morphological transformations to generate a self organized critical connectivity network map (SOCCNM in 2-dimensional space. This simple and elegant framework is implemented on a section that contains a few simulated water bodies to generate SOCCNM. This is based on a postulate that the randomly situated surface water bodies of various sizes and shapes self organize during flooding process.

  17. A non-random variation of monthly average temperatures and precipitation quantities in Romania during the period 2009-2012

    Directory of Open Access Journals (Sweden)

    Vlad D. MIRCOV

    2014-06-01

    Full Text Available Within this study we reflect non-randomness in the series of data concerning monthly average temperature and precipitation values registered in Romania during the period 2009-2012. We identified the slow increase in the monthly average temperature with 0.040C/months and a low decrease of average precipitation quantity with 0.29 mm/month. We also revealed that monthly average temperature and precipitation quantities series of data exposed behaviour close to Brown noise. The complex nature of the climate system and the unpredictability of weather are also reflected.

  18. Structural variation in the chicken genome identified by paired-end next-generation DNA sequencing of reduced representation libraries

    Directory of Open Access Journals (Sweden)

    Okimoto Ron

    2011-02-01

    Full Text Available Abstract Background Variation within individual genomes ranges from single nucleotide polymorphisms (SNPs to kilobase, and even megabase, sized structural variants (SVs, such as deletions, insertions, inversions, and more complex rearrangements. Although much is known about the extent of SVs in humans and mice, species in which they exert significant effects on phenotypes, very little is known about the extent of SVs in the 2.5-times smaller and less repetitive genome of the chicken. Results We identified hundreds of shared and divergent SVs in four commercial chicken lines relative to the reference chicken genome. The majority of SVs were found in intronic and intergenic regions, and we also found SVs in the coding regions. To identify the SVs, we combined high-throughput short read paired-end sequencing of genomic reduced representation libraries (RRLs of pooled samples from 25 individuals and computational mapping of DNA sequences from a reference genome. Conclusion We provide a first glimpse of the high abundance of small structural genomic variations in the chicken. Extrapolating our results, we estimate that there are thousands of rearrangements in the chicken genome, the majority of which are located in non-coding regions. We observed that structural variation contributes to genetic differentiation among current domesticated chicken breeds and the Red Jungle Fowl. We expect that, because of their high abundance, SVs might explain phenotypic differences and play a role in the evolution of the chicken genome. Finally, our study exemplifies an efficient and cost-effective approach for identifying structural variation in sequenced genomes.

  19. On the sum of squared η-μ random variates with application to the performance of wireless communication systems

    KAUST Repository

    Ansari, Imran Shafique

    2013-06-01

    The probability density function (PDF) and cumulative distribution function of the sum of L independent but not necessarily identically distributed squared η-μ variates, applicable to the output statistics of maximal ratio combining (MRC) receiver operating over η-μ fading channels that includes the Hoyt and the Nakagami-m models as special cases, is presented in closed-form in terms of the Fox\\'s H function. Further analysis, particularly on the bit error rate via PDF-based approach, is also represented in closed form in terms of the extended Fox\\'s H function (H). The proposed new analytical results complement previous results and are illustrated by extensive numerical and Monte Carlo simulation results. © 2013 IEEE.

  20. Sleep quality and body composition variations in obese male adults after 14 weeks of yoga intervention: A randomized controlled trial

    Directory of Open Access Journals (Sweden)

    P B Rshikesan

    2017-01-01

    Full Text Available Background: Obesity is a big challenge all over the world. It is associated with many noncommunicable diseases. Yoga known to be add-on treatment may be effective for obesity control. Aim: To assess the effect of integrated approach of yoga therapy (IAYT for body composition and quality of sleep in adult obese male. Subjects and Methods: A randomized controlled trial was conducted for 14 weeks on obese male of urban setting. Eighty individuals were randomly divided into two groups, i.e., yoga group (n = 40; age; 40.03 ± 8.74 years, body mass index [BMI] 28.7 ± 2.35 kg/m2 and control group (age; 42.20 ± 12.06 years, BMI 27.70 ± 2.05 kg/m2. The IAYT was imparted to yoga group for 1½ hour for 5 days in a week for 14 weeks. The control group continued their regular activities. The body composition by InBody R20 and sleep quality by Pittsburgh Sleep Quality Index (PSQI were assessed. Statistical analysis was done for within and between groups using SPSS version 21. The correlation analysis was done on the difference in pre-post values. Results: The results showed that weight (P = 0.004, BMI (P = 0.008, bone mass (P = 0.017, obesity degree (P = 0.005, and mineral mass (P = 0.046 were improved in yoga group and no change in control group (P > 0.05. The global score of PSQI improved (P = 0.017 in yoga group alone. Conclusion: The results indicate the beneficial effects of IAYT on body composition and sleep quality in obese males. The yoga practice may reduce obesity with the improvement in quality of life.

  1. Pressure support improves oxygenation and lung protection compared to pressure-controlled ventilation and is further improved by random variation of pressure support.

    Science.gov (United States)

    Spieth, Peter M; Carvalho, Alysson R; Güldner, Andreas; Kasper, Michael; Schubert, René; Carvalho, Nadja C; Beda, Alessandro; Dassow, Constanze; Uhlig, Stefan; Koch, Thea; Pelosi, Paolo; Gama de Abreu, Marcelo

    2011-04-01

    To explore whether 1) conventional pressure support ventilation improves lung function and attenuates the pulmonary inflammatory response compared to pressure-controlled ventilation and 2) random variation of pressure support levels (noisy pressure support ventilation) adds further beneficial effects to pressure support ventilation. Three-arm, randomized, experimental study. University hospital research facility. Twenty-four juvenile pigs. Acute lung injury was induced by surfactant depletion. Animals were randomly assigned to 6 hrs of mechanical ventilation (n = 8 per group) with either 1) pressure-controlled ventilation, 2) pressure support ventilation, or 3) noisy pressure support ventilation. During noisy pressure support ventilation, the pressure support varied randomly, with values following a normal distribution. In all groups, the driving pressures were set to achieve a mean tidal volume of 6 mL/kg. At the end of experiments, animals were killed and lungs extracted for histologic and biochemical analysis. Respiratory, gas-exchange, and hemodynamics variables were assessed hourly. The diffuse alveolar damage and the inflammatory response of lungs were quantified. Pressure support ventilation and noisy pressure support ventilation improved gas exchange and were associated with reduced histologic damage and interleukin-6 concentrations in lung tissue compared to pressure-controlled ventilation. Noisy pressure support ventilation further improved gas exchange and decreased the inspiratory effort while reducing alveolar edema and inflammatory infiltration compared to pressure support ventilation. In this model of acute lung injury, pressure support ventilation and noisy pressure support ventilation attenuated pulmonary inflammatory response and improved gas exchange as compared to pressure-controlled ventilation. Noisy pressure support ventilation further improved gas exchange, reduced the inspiratory effort, and attenuated alveolar edema and inflammatory

  2. Exact distribution of a pattern in a set of random sequences generated by a Markov source: applications to biological data

    Directory of Open Access Journals (Sweden)

    Regad Leslie

    2010-01-01

    Full Text Available Abstract Background In bioinformatics it is common to search for a pattern of interest in a potentially large set of rather short sequences (upstream gene regions, proteins, exons, etc.. Although many methodological approaches allow practitioners to compute the distribution of a pattern count in a random sequence generated by a Markov source, no specific developments have taken into account the counting of occurrences in a set of independent sequences. We aim to address this problem by deriving efficient approaches and algorithms to perform these computations both for low and high complexity patterns in the framework of homogeneous or heterogeneous Markov models. Results The latest advances in the field allowed us to use a technique of optimal Markov chain embedding based on deterministic finite automata to introduce three innovative algorithms. Algorithm 1 is the only one able to deal with heterogeneous models. It also permits to avoid any product of convolution of the pattern distribution in individual sequences. When working with homogeneous models, Algorithm 2 yields a dramatic reduction in the complexity by taking advantage of previous computations to obtain moment generating functions efficiently. In the particular case of low or moderate complexity patterns, Algorithm 3 exploits power computation and binary decomposition to further reduce the time complexity to a logarithmic scale. All these algorithms and their relative interest in comparison with existing ones were then tested and discussed on a toy-example and three biological data sets: structural patterns in protein loop structures, PROSITE signatures in a bacterial proteome, and transcription factors in upstream gene regions. On these data sets, we also compared our exact approaches to the tempting approximation that consists in concatenating the sequences in the data set into a single sequence. Conclusions Our algorithms prove to be effective and able to handle real data sets with

  3. Exact distribution of a pattern in a set of random sequences generated by a Markov source: applications to biological data

    Science.gov (United States)

    2010-01-01

    Background In bioinformatics it is common to search for a pattern of interest in a potentially large set of rather short sequences (upstream gene regions, proteins, exons, etc.). Although many methodological approaches allow practitioners to compute the distribution of a pattern count in a random sequence generated by a Markov source, no specific developments have taken into account the counting of occurrences in a set of independent sequences. We aim to address this problem by deriving efficient approaches and algorithms to perform these computations both for low and high complexity patterns in the framework of homogeneous or heterogeneous Markov models. Results The latest advances in the field allowed us to use a technique of optimal Markov chain embedding based on deterministic finite automata to introduce three innovative algorithms. Algorithm 1 is the only one able to deal with heterogeneous models. It also permits to avoid any product of convolution of the pattern distribution in individual sequences. When working with homogeneous models, Algorithm 2 yields a dramatic reduction in the complexity by taking advantage of previous computations to obtain moment generating functions efficiently. In the particular case of low or moderate complexity patterns, Algorithm 3 exploits power computation and binary decomposition to further reduce the time complexity to a logarithmic scale. All these algorithms and their relative interest in comparison with existing ones were then tested and discussed on a toy-example and three biological data sets: structural patterns in protein loop structures, PROSITE signatures in a bacterial proteome, and transcription factors in upstream gene regions. On these data sets, we also compared our exact approaches to the tempting approximation that consists in concatenating the sequences in the data set into a single sequence. Conclusions Our algorithms prove to be effective and able to handle real data sets with multiple sequences, as well

  4. K-Ras(G12D)-selective inhibitory peptides generated by random peptide T7 phage display technology.

    Science.gov (United States)

    Sakamoto, Kotaro; Kamada, Yusuke; Sameshima, Tomoya; Yaguchi, Masahiro; Niida, Ayumu; Sasaki, Shigekazu; Miwa, Masanori; Ohkubo, Shoichi; Sakamoto, Jun-Ichi; Kamaura, Masahiro; Cho, Nobuo; Tani, Akiyoshi

    2017-03-11

    Amino-acid mutations of Gly 12 (e.g. G12D, G12V, G12C) of V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (K-Ras), the most promising drug target in cancer therapy, are major growth drivers in various cancers. Although over 30 years have passed since the discovery of these mutations in most cancer patients, effective mutated K-Ras inhibitors have not been marketed. Here, we report novel and selective inhibitory peptides to K-Ras(G12D). We screened random peptide libraries displayed on T7 phage against purified recombinant K-Ras(G12D), with thorough subtraction of phages bound to wild-type K-Ras, and obtained KRpep-2 (Ac-RRCPLYISYDPVCRR-NH 2 ) as a consensus sequence. KRpep-2 showed more than 10-fold binding- and inhibition-selectivity to K-Ras(G12D), both in SPR analysis and GDP/GTP exchange enzyme assay. K D and IC 50 values were 51 and 8.9 nM, respectively. After subsequent sequence optimization, we successfully generated KRpep-2d (Ac-RRRRCPLYISYDPVCRRRR-NH 2 ) that inhibited enzyme activity of K-Ras(G12D) with IC 50  = 1.6 nM and significantly suppressed ERK-phosphorylation, downstream of K-Ras(G12D), along with A427 cancer cell proliferation at 30 μM peptide concentration. To our knowledge, this is the first report of a K-Ras(G12D)-selective inhibitor, contributing to the development and study of K-Ras(G12D)-targeting drugs. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Casting epPCR (cepPCR): A simple random mutagenesis method to generate high quality mutant libraries.

    Science.gov (United States)

    Yang, Jianhua; Ruff, Anna J; Arlt, Marcus; Schwaneberg, Ulrich

    2017-09-01

    During the last decade, directed evolution has become a standard protein engineering strategy to reengineer proteins for industrial applications under high stress conditions (e.g., high temperature, extreme pH, ionic liquids, or organic solvents). The most commonly employed method for diversity generation to improve biocatalysts for these properties is random mutagenesis by error-prone polymerase chain reaction (epPCR). However, recent reports show that epPCR often fails to produce >70% of beneficial positions/amino acid exchanges which improve enzyme properties such as organic solvent or ionic liquid resistance. In this report, bsla (543 bp, small lipase gene from Bacillus subtilis) was divided into three fragments (147, 192, 204 bp). Each fragment was subjected to an epPCR with a high mutation load (22, 31, and 33 mutations per kb) in order to increase the number of identified beneficial positions while maintaining a fraction of active population which can efficiently be screened in agar plate or microtiter plate format. The use of this "casting epPCR" process termed as (cepPCR), doubles the number of identified beneficial positions (from 14% to 29%), when compared to standard epPCR for the BSLA enzyme model. A further increase to 39% of beneficial positions is obtainable through combination of cepPCR with the transversion biased sequence saturation mutagenesis (SeSaM) method. Furthermore, sequencing of up to 600 mutations per fragment provided valuable insights into the correlation of total throughput and number of identified beneficial positions as well as how an efficient balance of screening efforts to obtainable results can be achieved in directed evolution campaigns. Biotechnol. Bioeng. 2017;114: 1921-1927. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  6. Shopper typologies amongst a Generation Y consumer cohort and variations in terms of age in the fashion apparel market

    Directory of Open Access Journals (Sweden)

    Chengedzai Mafini

    2014-04-01

    Rational: Marketers have ever been concerned with the behaviour of consumers. Generation Y consumers have emerged as an important marketing segment. Consequently, a need exists to investigate behavioural issues pertaining to this age cohort on a continuous basis. Methodology: A survey questionnaire was administered to a convenient sample of 230 Generation Y consumers of fashion apparel. Exploratory factor analysis was used to identify shopper typologies. The Kruskal-Wallis test was used to examine the influence of age on the identified shopper typologies. Findings: The study identified seven shopper typologies that are applicable to the Generation Y cohort. These are quality conscious, brand conscious, novelty seeking, hedonistic, confused by over-choice, habitual, brand loyal and fashion conscious shopper typologies. The study also revealed that younger consumers were found to be more confused by over-choice than their older counterparts. Value of research: These findings may enable marketers to understand and predict the purchase behaviour of Generation Y consumers, thereby facilitating the development and implementation of more effective marketing strategies.

  7. Capturing chloroplast variation for molecular ecology studies: a simple next generation sequencing approach applied to a rainforest tree

    OpenAIRE

    McPherson, Hannah; van der Merwe, Marlien; Delaney, Sven K; Edwards, Mark A; Henry, Robert J; McIntosh, Emma; Rymer, Paul D; Milner, Melita L; Siow, Juelian; Rossetto, Maurizio

    2013-01-01

    Background With high quantity and quality data production and low cost, next generation sequencing has the potential to provide new opportunities for plant phylogeographic studies on single and multiple species. Here we present an approach for in silicio chloroplast DNA assembly and single nucleotide polymorphism detection from short-read shotgun sequencing. The approach is simple and effective and can be implemented using standard bioinformatic tools. Results The chloroplast genome of Toona ...

  8. Genetics of autism spectrum disorder: an update on copy number variations leading to autism in the next generation sequencing era.

    Science.gov (United States)

    AlSagob, Maysoon; Colak, Dilek; Kaya, Namik

    2015-05-01

    Autism spectrum disorder (ASD) is a large group of neurodevelopmental conditions that share common characteristics such as social and language impairment and repetitive and stereotypic behaviors. It is reported that ASD is on increase in recent years reaching ratios up to 1 in 68 children. The disease is seen four times more frequently in males than females. ASD is heritable with complex inheritance and genetic heterogeneity, and frequently coexists with other diseases such as intellectual disability, seizure disorders, and fragile-x. Recent advances in genomic technologies have led to a greater understanding of genetic mechanisms in ASD, discovery of novel genetic loci and risk factors, as well as submicroscopic chromosomal changes also known as copy number variations (CNVs). Here we review recent developments in the genetics field and hereditary and sporadic CNVs leading to ASD.

  9. The Tracking Study: description of a randomized controlled trial of variations on weight tracking frequency in a behavioral weight loss program.

    Science.gov (United States)

    Linde, Jennifer A; Jeffery, Robert W; Crow, Scott J; Brelje, Kerrin L; Pacanowski, Carly R; Gavin, Kara L; Smolenski, Derek J

    2015-01-01

    Observational evidence from behavioral weight control trials and community studies suggests that greater frequency of weighing oneself, or tracking weight, is associated with better weight outcomes. Conversely, it has also been suggested that frequent weight tracking may have a negative impact on mental health and outcomes during weight loss, but there are minimal experimental data that address this concern in the context of an active weight loss program. To achieve the long-term goal of strengthening behavioral weight loss programs, the purpose of this randomized controlled trial (the Tracking Study) is to test variations on frequency of self-weighing during a behavioral weight loss program, and to examine psychosocial and mental health correlates of weight tracking and weight loss outcomes. This paper describes the study design, intervention features, recruitment, and baseline characteristics of participants enrolled in the Tracking Study. Three hundred thirty-nine overweight and obese adults were recruited and randomized to one of three variations on weight tracking frequency during a 12-month weight loss program with a 12-month follow-up: daily weight tracking, weekly weight tracking, or no weight tracking. The primary outcome is weight in kilograms at 24 months. The weight loss program integrates each weight tracking instruction with standard behavioral weight loss techniques (goal setting, self-monitoring, stimulus control, dietary and physical activity enhancements, lifestyle modifications); participants in weight tracking conditions were provided with wireless Internet technology (wi-fi-enabled digital scales and touchscreen personal devices) to facilitate weight tracking during the study. This study was successful in recruiting adult male and female participants and is positioned to enhance the standard of care with regard to weight tracking recommendations. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Causes of variation in BCG vaccine efficacy: examining evidence from the BCG REVAC cluster randomized trial to explore the masking and the blocking hypotheses.

    Science.gov (United States)

    Barreto, Mauricio L; Pilger, Daniel; Pereira, Susan M; Genser, Bernd; Cruz, Alvaro A; Cunha, Sergio S; Sant'Anna, Clemax; Hijjar, Miguel A; Ichihara, Maria Y; Rodrigues, Laura C

    2014-06-24

    BCG protection varies and in some places (nearest the equator) is low or absent. Understanding this variation can inform the efforts to develop new vaccines against tuberculosis. Two main hypotheses are used to explain this variation: under masking, new vaccines are unlikely to increase protection; under blocking new vaccines have a greater potential to be effective when BCG is not. We conducted a cluster randomized trial to explored the masking and blocking hypotheses by studying BCG vaccine efficacy of neonatal vaccination and when administered for the first or a second (revaccination) time at school age in two sites (Manaus close and Salvador further south from the equator). Seven hundred and sixty three state schools were matched on socio economic characteristics of the neighborhood and 239,934 children were randomized to vaccine (BCG vaccination at school age) or control group. Protection by first BCG vaccination at school age was high in Salvador (34%, 95% CI 7-53%, p=0.017) but low in Manaus (8%, 95% CI t0 39-40%, p=0.686). For revaccination at school age, protection was modest in Salvador (19%, 95% CI 3-33%, p=0.022) and absent in Manaus (1%, 95% CI to 27-23%, p=0.932). Vaccine efficacy for neonatal vaccination was similar in Salvador (40%, 95% CI 22-54%, pBCG efficacy was marked when vaccine was given at school age but absent at birth, which points towards blocking as the dominant mechanism. New tuberculosis vaccines that overcome or by pass this blocking effect could confer protection in situations where BCG is not protective. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Multifunctional Polymeric Scaffolds for Enhancement of PARACEST Contrast Sensitivity and Performance: The Effects of Random Copolymer Variations

    Science.gov (United States)

    Wu, Yunkou; Zhao, Piyu; Kiefer, Garry E.; Sherry, A. Dean

    2010-01-01

    A DOTA (1,4,7,10-tetraazacyclododecane-N,N’,N“,N’”-tetraacetic acid) tetraamide ligand having a single acrylamide side-chain (M1) was copolymerized with either 2-methylacrylic acid (MAA), 2-(acryloylamino)-2-methyl-1-propanesulfonic acid (AMPS) or N-isopropylacrylamide (NIPAM) to create a series of linear random copolymers using classical free radical chain polymerization chemistry. The metal ion binding properties of hydrolyzed M1 were investigated by pH potentiometry and the europium (III) complexes of the resulting heteropolymers were evaluated as PARACEST imaging agents. All polymeric agents were found to possess similar intermediate-to-slow water exchange and CEST characteristics as the parent EuDOTA-tetraamide monomer. Consistent with basic multiplexing principles, the highest molecular weight polymer, Eu-DMAA 3.1, also showed the highest CEST sensitivity with a detection limit of 20 ± 2 μM. The second arylamide component gave polymers with widely different chemical characteristics and CEST properties. In particular, the Eu-DNIPAM 4.0 and Eu-DMAA 4.1 polymers displayed different solubility characteristics as a function of pH or temperature which, in turn, affected the water exchange and CEST properties of the corresponding agents. It was concluded that introduction of hydrophobic groups into the polymer backbone reduces solvent accessibility to the Eu3+ component, effectively slowing water exchange between the inner-sphere water coordination position at each Eu3+ center with bulk water. The CEST properties of the heteropolymers when dissolved in plasma suggest that the more hydrophobic characteristics of these polymers could be advantageous for in vivo applications. PMID:20838469

  12. Combined Effects Of Stress Work And Heat Generation On MHD Natural Convection Flow Along A Vertical Flat Plate With Power Law Variation Of Uniform Surface Temperature

    Directory of Open Access Journals (Sweden)

    Mohammad Mahfuzul Islam

    2015-08-01

    Full Text Available Abstract In this paper is presented to study conjugate effects of stress work and heat generation on MHD natural convection flow along a vertical flat plate with power law variation of surface temperature. Stress work and heat generation effects on magneto-hydrodynamics natural convection flows are considered in this investigation. With a goal to attain similarity solutions of the problem the developed equations are made dimensionless by using suitable transformations. The non-dimensional equations are then transformed into non-similar forms by introducing non- similarity transformations. The resulting non-similar equations together with their corresponding boundary conditions based on conduction and convection are solved numerically by using the shooting method of Nachtsheim-swigert iteration technique and finite difference method together with Keller box Scheme. Numerically calculated velocity profiles and temperature profiles skin friction and the rate of heat transfer coefficient are shown on graphs for different values of the parameters entering into the problem.

  13. Determination of Genetic Variations of Toll-Like Receptor (TLR 2, 4, and 6 with Next-Generation Sequencing in Native Cattle Breeds of Anatolia and Holstein Friesian

    Directory of Open Access Journals (Sweden)

    Nuket Bilgen

    2016-11-01

    Full Text Available In recent years, the focus of disease resistance and susceptibility studies in cattle have been on determining patterns in the innate immune response of key proteins, such as Toll-like receptors (TLR. In the bovine genome, there are 10 TLR family members and, of these, TLR2, TLR4, and TLR6 are specialized in the recognition of bacterial ligands. Indigenous cattle breeds of Anatolia have been reported to show fewer signs of clinical bacterial infections, such as bovine tuberculosis and mastitis, and it is hypothesized that this might be due to a less stringent genetic selection during breeding. In contrast, Holstein-Friesian cattle have been under strong selection for milk production, which may have resulted in greater susceptibility to diseases. To test this hypothesis, we have compared the TLR2, TLR4, and TLR6 genes of Anatolian Black (AB, East Anatolian Red (EAR, South Anatolian Red (SAR, Turkish Grey (TG, and Holstein (HOL cattle using next-generation sequencing. The SAR breed had the most variations overall, followed by EAR, AB, TG, and HOL. TG had the most variations for TLR2, whereas SAR had the most variations in TLR4 and TLR6. We compared these variants with those associated with disease and susceptibility traits. We used exon variants to construct haplotypes, investigated shared haplotypes within breeds, and proposed candidate haplotypes for a disease resistance phenotype in Anatolian cattle breeds.

  14. Predicting the velocity and azimuth of fragments generated by the range destruction or random failure of rocket casings and tankage

    Science.gov (United States)

    Eck, M.; Mukunda, M.

    The proliferation of space vehicle launch sites and the projected utilization of these facilities portends an increase in the number of on-pad, ascent, and on-orbit solid-rocket motor (SRM) casings and liquid-rocket tanks which will randomly fail or will fail from range destruct actions. Beyond the obvious safety implications, these failures may have serious resource implications for mission system and facility planners. SRM-casing failures and liquid-rocket tankage failures result in the generation of large, high velocity fragments which may be serious threats to the safety of launch support personnel if proper bunkers and exclusion areas are not provided. In addition, these fragments may be indirect threats to the general public's safety if they encounter hazardous spacecraft payloads which have not been designed to withstand shrapnel of this caliber. They may also become threats to other spacecraft if, by failing on-orbit, they add to the ever increasing space-junk collision cross-section. Most prior attempts to assess the velocity of fragments from failed SRM casings have simply assigned the available chamber impulse to available casing and fuel mass and solved the resulting momentum balance for velocity. This method may predict a fragment velocity which is high or low by a factor of two depending on the ratio of fuel to casing mass extant at the time of failure. Recognizing the limitations of existing methods, the authors devised an analytical approach which properly partitions the available impulse to each major system-mass component. This approach uses the Physics International developed PISCES code to couple the forces generated by an Eulerian modeled gas flow field to a Lagrangian modeled fuel and casing system. The details of a predictive analytical modeling process as well as the development of normalized relations for momentum partition as a function of SRM burn time and initial geometry are discussed in this paper. Methods for applying similar modeling

  15. Study on Power Loss Reduction Considering Load Variation with Large Penetration of Distributed Generation in Smart Grid

    Science.gov (United States)

    Liu, Chang; Lv, Xiangyu; Guo, Li; Cai, Lixia; Jie, Jinxing; Su, Kuo

    2017-05-01

    With the increasing of penetration of distributed in the smart grid, the problems that the power loss increasing and short circuit capacity beyond the rated capicity of circuit breaker will become more serious. In this paper, a methodology (Modified BPSO) is presented for network reconfiguration which is based on hybrid approach of Tabu Search and BPSO algorithms to prevent the local convergence and to decrease the calculation time using double fitnesses to consider the constraints. Moreover, an average load simulated method (ALS method) load variation considered is proposed that the average load value is used to instead of the actual load to calculation. Finally, from a case study, the results of simulation certify the approaches will decrease drastically the losses and improve the voltage profiles obviously, at the same time, the short circuit capacity is also decreased into less the shut-off capacity of circuit breaker. The power losses won’t be increased too much even if the short circuit capacity constraint is considered; voltage profiles are better with the constraint of short circuit capacity considering. The ALS method is simple and calculated time is speed.

  16. The next generation of target capture technologies - large DNA fragment enrichment and sequencing determines regional genomic variation of high complexity.

    Science.gov (United States)

    Dapprich, Johannes; Ferriola, Deborah; Mackiewicz, Kate; Clark, Peter M; Rappaport, Eric; D'Arcy, Monica; Sasson, Ariella; Gai, Xiaowu; Schug, Jonathan; Kaestner, Klaus H; Monos, Dimitri

    2016-07-09

    The ability to capture and sequence large contiguous DNA fragments represents a significant advancement towards the comprehensive characterization of complex genomic regions. While emerging sequencing platforms are capable of producing several kilobases-long reads, the fragment sizes generated by current DNA target enrichment technologies remain a limiting factor, producing DNA fragments generally shorter than 1 kbp. The DNA enrichment methodology described herein, Region-Specific Extraction (RSE), produces DNA segments in excess of 20 kbp in length. Coupling this enrichment method to appropriate sequencing platforms will significantly enhance the ability to generate complete and accurate sequence characterization of any genomic region without the need for reference-based assembly. RSE is a long-range DNA target capture methodology that relies on the specific hybridization of short (20-25 base) oligonucleotide primers to selected sequence motifs within the DNA target region. These capture primers are then enzymatically extended on the 3'-end, incorporating biotinylated nucleotides into the DNA. Streptavidin-coated beads are subsequently used to pull-down the original, long DNA template molecules via the newly synthesized, biotinylated DNA that is bound to them. We demonstrate the accuracy, simplicity and utility of the RSE method by capturing and sequencing a 4 Mbp stretch of the major histocompatibility complex (MHC). Our results show an average depth of coverage of 164X for the entire MHC. This depth of coverage contributes significantly to a 99.94 % total coverage of the targeted region and to an accuracy that is over 99.99 %. RSE represents a cost-effective target enrichment method capable of producing sequencing templates in excess of 20 kbp in length. The utility of our method has been proven to generate superior coverage across the MHC as compared to other commercially available methodologies, with the added advantage of producing longer sequencing

  17. Composition, peat-forming vegetation and kerogen paraffinicity of Cenozoic coals: Relationship to variations in the petroleum generation potential (Hydrogen Index)

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, H.I.; Lindstroem, S.; Nytoft, H.P.; Rosenberg, P. [Geological Survey of Denmark and Greenland (GEUS), Oester Voldgade 10, DK-1350 Copenhagen (Denmark)

    2009-04-01

    Coals with similar thermal maturity and from the same deposit normally show a considerable range in petroleum generation potential as measured by the Hydrogen Index (HI). This variation may partly be related to variations in plant input to the precursor mires and organic matter preservation. It is widely accepted that some Cenozoic coals and coaly sediments have the potential to generate oil, which is related to the coal's paraffinicity. Coal paraffinicity is not readily reflected in the bulk HI. In this paper, the relationships between measured HI and coal composition, coal kerogen paraffinicity and floral input have been investigated in detail for three sets of coals from Colombia/Venezuela, Indonesia, and Vietnam. The samples in each coal set are largely of iso-rank. The petroleum generation potential was determined by Rock-Eval pyrolysis. Reflected light microscopy was used to analyse the organic matter (maceral) composition and the thermal maturity was determined by vitrinite reflectance (VR) measurements. The botanical affinity of pollen and spores was analysed by palynology. Coal kerogen paraffinicity was determined by ruthenium tetroxide-catalysed oxidation (RTCO) followed by chain length analysis and quantification (mg/g TOC) of the liberated aliphatic chains. The coals are dominated by huminite, in particular detrohuminite. Only the Vietnamese coals are rich in microscopically visible liptinite. The pollen and spores suggest that the coals were derived principally from complex angiosperm mire vegetations, with subordinate proportions of ferns that generally grew in a subtropical to tropical climate. Measured HI values vary considerably, but for the majority of the coals the values lie between approximately 200 mg HC/g TOC and 300 mg HC/g TOC. Aliphatics yielding monocarboxylic acids dominate in the coal kerogen, whereas aliphatics yielding dicarboxylic acids are secondary. However, the dicarboxylic acids show that cross-linking long-chain aliphatics

  18. A next generation enzymatic magnesium assay on the Abbott ARCHITECT chemistry system meets performance goals based on biological variation.

    Science.gov (United States)

    Bailey, D; Martens, P; Mah, W; Yip, P M

    2014-01-01

    To evaluate the performance of the Abbott ARCHITECT enzymatic assay for magnesium (3P68) in serum/plasma and urine against analytical goals based on biological variation. Analytical performance was evaluated according to CLSI protocols. Precision was examined using commercial chemistry controls. Accuracy was assessed against NIST SRM 956c, electrolytes in human serum. Correlation with the arsenazo Mg assay (7D70) was completed using patient samples (plasma, N = 101; urine, N = 90). Common interferences were examined in pooled patient specimens with high and low magnesium concentrations. The enzymatic Mg assay displayed imprecision of 1.7% at 0.72 mmol/L and 1.4% at 1.80 mmol/L (20 days, one calibration, one reagent lot). The linear range was verified between 0.18-7.0 mmol/L (plasma) and 0.01-10.69 mmol/L (urine). Results of the enzymatic assay (x) correlated well with the predicate assay (y) with the relationships y = 0.891x + 0.035, R = 0.967 (plasma) and y = 1.181x + 0.086, R = 0.997 (urine). Mean bias of the NIST SRM 956 c samples was -1.4%. This method showed minimal interference by hemoglobin (3g/L as hemolysate), lipemia (20 g/L Intralipid), unconjugated bilirubin (531 μmol/L), and ascorbate (680 μmol/L). The ARCHITECT Magnesium assay 3P68 achieved the desirable analytical quality specification of 4.8% for total allowable error. In comparison to the 7D70 assay, notable improvements are seen in precision, 30-day calibration stability, and minimal interference by hemolyzed and lipemic samples. © 2013.

  19. Autocorrelation peaks in congruential pseudorandom number generators

    Science.gov (United States)

    Neuman, F.; Merrick, R. B.

    1976-01-01

    The complete correlation structure of several congruential pseudorandom number generators (PRNG) of the same type and small cycle length was studied to deal with the problem of congruential PRNG almost repeating themselves at intervals smaller than their cycle lengths, during simulation of bandpass filtered normal random noise. Maximum period multiplicative and mixed congruential generators were studied, with inferences drawn from examination of several tractable members of a class of random number generators, and moduli from 2 to the 5th power to 2 to the 9th power. High correlation is shown to exist in mixed and multiplicative congruential random number generators and prime moduli Lehmer generators for shifts a fraction of their cycle length. The random noise sequences in question are required when simulating electrical noise, air turbulence, or time variation of wind parameters.

  20. Numerical Research on Hydraulically Generated Vibration and Noise of a Centrifugal Pump Volute with Impeller Outlet Width Variation

    Directory of Open Access Journals (Sweden)

    Houlin Liu

    2014-01-01

    Full Text Available The impeller outlet width of centrifugal pumps is of significant importance for numbers of effects. In the paper, these effects including the performance, pressure pulsations, hydraulically generated vibration, and noise level are investigated. For the purpose, two approaches were used to predict the vibration and sound radiation of the volute under fluid excitation force. One approach is the combined CFD/FEM analysis for structure vibration, and then the structure response obtained from the FEM analysis is treated as the boundary condition for BEM analysis for sound radiation. The other is the combined CFD/FEM/BEM coupling method. Before the numerical methods were used, the simulation results were validated by the vibration acceleration of the monitoring points on the volute. The vibration and noise were analyzed and compared at three flow conditions. The analysis of the results shows that the influences of the sound pressure of centrifugal pumps on the structure appear insignificant. The relative outlet width b2* at nq(SI = 26.7 in this paper should be less than 0.06, based on an overall consideration of the pump characteristics, pressure pulsations, vibration and noise level.

  1. Automated Learning of Subcellular Variation among Punctate Protein Patterns and a Generative Model of Their Relation to Microtubules.

    Directory of Open Access Journals (Sweden)

    Gregory R Johnson

    2015-12-01

    Full Text Available Characterizing the spatial distribution of proteins directly from microscopy images is a difficult problem with numerous applications in cell biology (e.g. identifying motor-related proteins and clinical research (e.g. identification of cancer biomarkers. Here we describe the design of a system that provides automated analysis of punctate protein patterns in microscope images, including quantification of their relationships to microtubules. We constructed the system using confocal immunofluorescence microscopy images from the Human Protein Atlas project for 11 punctate proteins in three cultured cell lines. These proteins have previously been characterized as being primarily located in punctate structures, but their images had all been annotated by visual examination as being simply "vesicular". We were able to show that these patterns could be distinguished from each other with high accuracy, and we were able to assign to one of these subclasses hundreds of proteins whose subcellular localization had not previously been well defined. In addition to providing these novel annotations, we built a generative approach to modeling of punctate distributions that captures the essential characteristics of the distinct patterns. Such models are expected to be valuable for representing and summarizing each pattern and for constructing systems biology simulations of cell behaviors.

  2. Identification and characterization of nucleotide variations in the genome of Ziziphus jujuba (Rhamnaceae) by next generation sequencing.

    Science.gov (United States)

    Ma, Qiuyue; Feng, Kai; Yang, Wanxu; Chen, Yingnan; Yu, Faxin; Yin, Tongming

    2014-05-01

    In this study, single-nucleotide polymorphisms (SNPs) and insertions/deletions (InDels) in the genome of Ziziphus jujuba were identified using sequences generated by the Roche 454 GS-FLX sequencer. A total of, 573,141 reads were produced with an average read length of 360 bp. After quality control, 258,754 of the filtered reads were assembled into 23,864 contigs, and 293,458 remained as singletons. Using the contig assemblies as a reference, 17,160 SNPs and 478 InDels were identified. Among the SNPs, transitions occurred three times more frequently than transversions. In transitions, the number of C/T and G/A transitions was similar. Among the transversions, A/T was the most abundant, and C/G was much rarer than any of the other types of transversions, accounting for only about half the numbers of A/C, A/T and G/T transversions. For the InDels, mononucleotide changes amounted to 64.4% of the total number of InDels. In general, the frequency of detected InDels decreased as the length of the InDels increased. This study provides valuable marker resources for future genetic studies of Ziziphus spp.

  3. Capturing chloroplast variation for molecular ecology studies: a simple next generation sequencing approach applied to a rainforest tree.

    Science.gov (United States)

    McPherson, Hannah; van der Merwe, Marlien; Delaney, Sven K; Edwards, Mark A; Henry, Robert J; McIntosh, Emma; Rymer, Paul D; Milner, Melita L; Siow, Juelian; Rossetto, Maurizio

    2013-03-14

    With high quantity and quality data production and low cost, next generation sequencing has the potential to provide new opportunities for plant phylogeographic studies on single and multiple species. Here we present an approach for in silicio chloroplast DNA assembly and single nucleotide polymorphism detection from short-read shotgun sequencing. The approach is simple and effective and can be implemented using standard bioinformatic tools. The chloroplast genome of Toona ciliata (Meliaceae), 159,514 base pairs long, was assembled from shotgun sequencing on the Illumina platform using de novo assembly of contigs. To evaluate its practicality, value and quality, we compared the short read assembly with an assembly completed using 454 data obtained after chloroplast DNA isolation. Sanger sequence verifications indicated that the Illumina dataset outperformed the longer read 454 data. Pooling of several individuals during preparation of the shotgun library enabled detection of informative chloroplast SNP markers. Following validation, we used the identified SNPs for a preliminary phylogeographic study of T. ciliata in Australia and to confirm low diversity across the distribution. Our approach provides a simple method for construction of whole chloroplast genomes from shotgun sequencing of whole genomic DNA using short-read data and no available closely related reference genome (e.g. from the same species or genus). The high coverage of Illumina sequence data also renders this method appropriate for multiplexing and SNP discovery and therefore a useful approach for landscape level studies of evolutionary ecology.

  4. System Mass Variation and Entropy Generation in 100k We Closed-Brayton-Cycle Space Power Systems

    Science.gov (United States)

    Barrett, Michael J.; Reid, Bryan M.

    2004-01-01

    State-of-the-art closed-Brayton-cycle (CBC) space power systems were modeled to study performance trends in a trade space characteristic of interplanetary orbiters. For working-fluid molar masses of 48.6, 39.9, and 11.9 kg/kmol, peak system pressures of 1.38 and 3.0 MPa and compressor pressure ratios ranging from 1.6 to 2.4, total system masses were estimated. System mass increased as peak operating pressure increased for all compressor pressure ratios and molar mass values examined. Minimum mass point comparison between 72 percent He at 1.38 MPa peak and 94 percent He at 3.0 MPa peak showed an increase in system mass of 14 percent. Converter flow loop entropy generation rates were calculated for 1.38 and 3.0 MPa peak pressure cases. Physical system behavior was approximated using a pedigreed NASA Glenn modeling code, Closed Cycle Engine Program (CCEP), which included realistic performance prediction for heat exchangers, radiators and turbomachinery.

  5. System Mass Variation and Entropy Generation in 100-kWe Closed-Brayton-Cycle Space Power Systems

    Science.gov (United States)

    Barrett, Michael J.; Reid, Bryan M.

    2004-01-01

    State-of-the-art closed-Brayton-cycle (CBC) space power systems were modeled to study performance trends in a trade space characteristic of interplanetary orbiters. For working-fluid molar masses of 48.6, 39.9, and 11.9 kg/kmol, peak system pressures of 1.38 and 3.0 MPa and compressor pressure ratios ranging from 1.6 to 2.4, total system masses were estimated. System mass increased as peak operating pressure increased for all compressor pressure ratios and molar mass values examined. Minimum mass point comparison between 72 percent He at 1.38 MPa peak and 94 percent He at 3.0 MPa peak showed an increase in system mass of 14 percent. Converter flow loop entropy generation rates were calculated for 1.38 and 3.0 MPa peak pressure cases. Physical system behavior was approximated using a pedigreed NASA Glenn modeling code, Closed Cycle Engine Program (CCEP), which included realistic performance prediction for heat exchangers, radiators and turbomachinery.

  6. Design of high-throughput and low-power true random number generator utilizing perpendicularly magnetized voltage-controlled magnetic tunnel junction

    Directory of Open Access Journals (Sweden)

    Hochul Lee

    2017-05-01

    Full Text Available A true random number generator based on perpendicularly magnetized voltage-controlled magnetic tunnel junction devices (MRNG is presented. Unlike MTJs used in memory applications where a stable bit is needed to store information, in this work, the MTJ is intentionally designed with small perpendicular magnetic anisotropy (PMA. This allows one to take advantage of the thermally activated fluctuations of its free layer as a stochastic noise source. Furthermore, we take advantage of the voltage dependence of anisotropy to temporarily change the MTJ state into an unstable state when a voltage is applied. Since the MTJ has two energetically stable states, the final state is randomly chosen by thermal fluctuation. The voltage controlled magnetic anisotropy (VCMA effect is used to generate the metastable state of the MTJ by lowering its energy barrier. The proposed MRNG achieves a high throughput (32 Gbps by implementing a 64×64 MTJ array into CMOS circuits and executing operations in a parallel manner. Furthermore, the circuit consumes very low energy to generate a random bit (31.5 fJ/bit due to the high energy efficiency of the voltage-controlled MTJ switching.

  7. Design of high-throughput and low-power true random number generator utilizing perpendicularly magnetized voltage-controlled magnetic tunnel junction

    Science.gov (United States)

    Lee, Hochul; Ebrahimi, Farbod; Amiri, Pedram Khalili; Wang, Kang L.

    2017-05-01

    A true random number generator based on perpendicularly magnetized voltage-controlled magnetic tunnel junction devices (MRNG) is presented. Unlike MTJs used in memory applications where a stable bit is needed to store information, in this work, the MTJ is intentionally designed with small perpendicular magnetic anisotropy (PMA). This allows one to take advantage of the thermally activated fluctuations of its free layer as a stochastic noise source. Furthermore, we take advantage of the voltage dependence of anisotropy to temporarily change the MTJ state into an unstable state when a voltage is applied. Since the MTJ has two energetically stable states, the final state is randomly chosen by thermal fluctuation. The voltage controlled magnetic anisotropy (VCMA) effect is used to generate the metastable state of the MTJ by lowering its energy barrier. The proposed MRNG achieves a high throughput (32 Gbps) by implementing a 64 ×64 MTJ array into CMOS circuits and executing operations in a parallel manner. Furthermore, the circuit consumes very low energy to generate a random bit (31.5 fJ/bit) due to the high energy efficiency of the voltage-controlled MTJ switching.

  8. Randomized two-way cross-over bioequivalence study of two amoxicillin formulations and inter-ethnicity pharmacokinetic variation in healthy Malay volunteers.

    Science.gov (United States)

    Liew, Kai Bin; Loh, Gabriel Onn Kit; Tan, Yvonne Tze Fung; Peh, Kok Khiang

    2014-09-01

    The objectives of this study were to develop a new deproteinization method to extract amoxicillin from human plasma and evaluate the inter-ethnic variation of amoxicillin pharmacokinetics in healthy Malay volunteers. A single-dose, randomized, fasting, two-period, two-treatment, two-sequence crossover, open-label bioequivalence study was conducted in 18 healthy Malay adult male volunteers, with one week washout period. The drug concentration in the sample was analyzed using high-performance liquid chromatography (UV-vis HPLC). The mean (standard deviation) pharmacokinetic parameter results of Moxilen® were: peak concentration (Cmax ), 6.72 (1.56) µg/mL; area under the concentration-time graph (AUC0-8 ), 17.79 (4.29) µg/mL h; AUC0-∞ , 18.84 (4.62) µg/mL h. Those of YSP Amoxicillin® capsule were: Cmax , 6.69 (1.44) µg/mL; AUC0-8 , 18.69 (3.78) µg/mL h; AUC00-∞ , 19.95 (3.81) µg/mL h. The 90% confidence intervals for the logarithmic transformed Cmax , AUC0-8 and AUC0-∞ of Moxilen® vs YSP Amoxicillin® capsule was between 0.80 and 1.25. Both Cmax and AUC met the predetermined criteria for assuming bioequivalence. Both formulations were well tolerated. The results showed significant inter-ethnicity variation in pharmacokinetics of amoxicillin. The Cmax and AUC of amoxicillin in Malay population were slightly lower compared with other populations. Copyright © 2014 John Wiley & Sons, Ltd.

  9. Age and Individual Differences in Controlled Force Exertion Measured by a Computer-Generated Sinusoidal and Quasi-Random Display

    Science.gov (United States)

    Nagasawa, Yoshinori; Demura, Shinichi

    2010-01-01

    This study examined age group and individual differences in controlled force exertion by emulating sinusoidal and quasi-random waveforms in 222 right-handed female adults aged 20 to 86 years. The subjects matched their submaximal grip strength by the dominant hand to changing demand values displayed as either a sinusoidal or a quasi-random…

  10. Long-term effectiveness of computer-generated tailored patient education on benzodiazepines : a randomized controlled trial

    NARCIS (Netherlands)

    Ten Wolde, Geeske Brecht; Dijkstra, Arie; Van Empelen, Pepijn; van den Hout, Wilbert; Neven, Arie Knuistingh; Zitman, Frans

    Aims Chronic benzodiazepine use is highly prevalent and is associated with a variety of negative health consequences. The present study examined the long-term effectiveness of a tailored patient education intervention on benzodiazepine use. Participants A randomized controlled trial was conducted

  11. Moderate consumption of wine, through both its phenolic compounds and alcohol content, promotes hydroxytyrosol endogenous generation in humans. A randomized controlled trial.

    Science.gov (United States)

    Pérez-Mañá, Clara; Farré, Magí; Rodríguez-Morató, Jose; Papaseit, Esther; Pujadas, Mitona; Fitó, Montserrat; Robledo, Patricia; Covas, Maria-Isabel; Cheynier, Véronique; Meudec, Emmanuelle; Escudier, Jean-Louis; de la Torre, Rafael

    2015-06-01

    In humans, urinary hydroxytyrosol (OHTyr) concentrations have been associated to alcohol and wine consumption. To explore the role of wine components on promoting an endogenous OHTyr generation we performed a cross-over, double-blind, randomized controlled clinical trial (n = 28 healthy volunteers). Ethanol (wine and vodka), dealcoholized wine, and placebo were administered. Alcohol, dealcoholized wine, and particularly wine promoted a de novo OHTyr generation in vivo in humans. Potential OHTyr precursors (tyrosine, tyrosol, tyramine) were investigated in rats. Tyrosol was metabolized to OHTyr. Collating both studies, it is postulated that an increased Tyr bioavailability, a shift to a reductive pathway in dopamine and tyramine oxidative metabolism, and the biotransformation of Tyr to OHTyr were mechanisms involved in the OHTyr endogenous generation. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Evaluation of the methodologies used to generate random pavement profiles based on the power spectral density: An approach based on the International Roughness Index

    Directory of Open Access Journals (Sweden)

    Boris Jesús Goenaga

    2017-01-01

    Full Text Available The pavement roughness is the main variable that produces the vertical excitation in vehicles. Pavement profiles are the main determinant of (i discomfort perception on users and (ii dynamic loads generated at the tire-pavement interface, hence its evaluation constitutes an essential step on a Pavement Management System. The present document evaluates two specific techniques used to simulate pavement profiles; these are the shaping filter and the sinusoidal approach, both based on the Power Spectral Density. Pavement roughness was evaluated using the International Roughness Index (IRI, which represents the most used index to characterize longitudinal road profiles. Appropriate parameters were defined in the simulation process to obtain pavement profiles with specific ranges of IRI values using both simulation techniques. The results suggest that using a sinusoidal approach one can generate random profiles with IRI values that are representative of different road types, therefore, one could generate a profile for a paved or an unpaved road, representing all the proposed categories defined by ISO 8608 standard. On the other hand, to obtain similar results using the shaping filter approximation a modification in the simulation parameters is necessary. The new proposed values allow one to generate pavement profiles with high levels of roughness, covering a wider range of surface types. Finally, the results of the current investigation could be used to further improve our understanding on the effect of pavement roughness on tire pavement interaction. The evaluated methodologies could be used to generate random profiles with specific levels of roughness to assess its effect on dynamic loads generated at the tire-pavement interface and user’s perception of road condition.

  13. Generator. Generator

    Energy Technology Data Exchange (ETDEWEB)

    Knoedler, R.; Bossmann, H.P.

    1992-03-12

    The invention refers to a thermo-electric generator, whose main part is a sodium concentration cell. In conventional thermo-electric generators of this kind, the sodium moving from a hot space to a colder space must be transported back to the hot space via a circulation pipe and a pump. The purpose of the invention is to avoid the disadvantages of this return transport. According to the invention, the thermo-electric generator is supported so that it can rotate, so that the position of each space relative to its propinquity to the heat source can be changed at any time.

  14. Generator. Generator

    Energy Technology Data Exchange (ETDEWEB)

    Bossmann, H.P.; Knoedler, R.

    1992-03-12

    The invention refers to a thermo-electric generator, which contains sodium as the means of heat transport. The sodium moves from the space of higher temperature through a space into the space of lower temperature. One can do without a pump for transporting the sodium back from the space of lower temperature to the space of higher temperature, as the thermo-electric generator can rotate around an axis. It is therefore possible to interchange the position of the two spaces relative to the heat source.

  15. Fully digital jerk-based chaotic oscillators for high throughput pseudo-random number generators up to 8.77Gbits/s

    KAUST Repository

    Mansingka, Abhinav S.

    2014-06-18

    This paper introduces fully digital implementations of four di erent systems in the 3rd order jerk-equation based chaotic family using the Euler approximation. The digitization approach enables controllable chaotic systems that reliably provide sinusoidal or chaotic output based on a selection input. New systems are introduced, derived using logical and arithmetic operations between two system implementations of different bus widths, with up to 100x higher maximum Lyapunov exponent than the original jerkequation based chaotic systems. The resulting chaotic output is shown to pass the NIST sp. 800-22 statistical test suite for pseudorandom number generators without post-processing by only eliminating the statistically defective bits. The systems are designed in Verilog HDL and experimentally verified on a Xilinx Virtex 4 FPGA for a maximum throughput of 15.59 Gbits/s for the native chaotic output and 8.77 Gbits/s for the resulting pseudo-random number generators.

  16. Antisepsis regimen in the surgical treatment of HPV generated cervical lesions: polyhexamethylene biguanide vs chlorhexidine. A randomized, double blind study.

    Science.gov (United States)

    Gerli, S; Bavetta, F; Di Renzo, G C

    2012-12-01

    To reduce the risk of local infections after surgical treatments for HPV infected cervical lesions, the post-operative regimen is generally based on the use of vaginal antimicrobial agents. The efficacy and safety of polyhexamethylene biguanide-based vaginal suppositories was compared to a similar chlorhexidine-based treatment, in the post recovery regimen after surgical treatment of cervical lesions. 50 women who underwent to CO2 laser therapy for cervical lesions were randomly assigned to receive 10 days of antiseptic treatment with chlorhexidine digluconate vaginal suppositories, or polyhexamethylene biguanide vaginal suppositories (Monogin®/Biguanelle® ovuli, Lo.Li. Pharma, Italy). A weekly follow-up check was performed for 6 weeks. Polyhexamethylene biguanide-based treatment showed improved efficacy compared to chlorhexidine, in terms of healing process and prevention of bacterial infections. Due to its safety and effectiveness, the vaginal treatment with polyhexamethylene biguanide is preferred to chlorexidine, in accordance with previously reported in vitro evidences.

  17. SPARSE: Seed Point Auto-Generation for Random Walks Segmentation Enhancement in medical inhomogeneous targets delineation of morphological MR and CT images.

    Science.gov (United States)

    Chen, Haibin; Zhen, Xin; Gu, Xuejun; Yan, Hao; Cervino, Laura; Xiao, Yang; Zhou, Linghong

    2015-03-08

    In medical image processing, robust segmentation of inhomogeneous targets is a challenging problem. Because of the complexity and diversity in medical images, the commonly used semiautomatic segmentation algorithms usually fail in the segmentation of inhomogeneous objects. In this study, we propose a novel algorithm imbedded with a seed point autogeneration for random walks segmentation enhancement, namely SPARSE, for better segmentation of inhomogeneous objects. With a few user-labeled points, SPARSE is able to generate extended seed points by estimating the probability of each voxel with respect to the labels. The random walks algorithm is then applied upon the extended seed points to achieve improved segmentation result. SPARSE is implemented under the compute unified device architecture (CUDA) programming environment on graphic processing unit (GPU) hardware platform. Quantitative evaluations are performed using clinical homogeneous and inhomogeneous cases. It is found that the SPARSE can greatly decrease the sensitiveness to initial seed points in terms of location and quantity, as well as the freedom of selecting parameters in edge weighting function. The evaluation results of SPARSE also demonstrate substantial improvements in accuracy and robustness to inhomogeneous target segmentation over the original random walks algorithm.

  18. On the short-term predictability of fully digital chaotic oscillators for pseudo-random number generation

    KAUST Repository

    Radwan, Ahmed Gomaa

    2014-06-18

    This paper presents a digital implementation of a 3rd order chaotic system using the Euler approximation. Short-term predictability is studied in relation to system precision, Euler step size and attractor size and optimal parameters for maximum performance are derived. Defective bits from the native chaotic output are neglected and the remaining pass the NIST SP. 800-22 tests without post-processing. The resulting optimized pseudorandom number generator has throughput up to 17.60 Gbits/s for a 64-bit design experimentally verified on a Xilinx Virtex 4 FPGA with logic utilization less than 1.85%.

  19. Development and comparison of algorithms for generating a scan sequence for a random access scanner. [ZAP (and flow charts for ZIP and SCAN), in FORTRAN for DEC-10

    Energy Technology Data Exchange (ETDEWEB)

    Eason, R. O.

    1980-09-01

    Many data acquisition systems incorporate high-speed scanners to convert analog signals into digital format for further processing. Some systems multiplex many channels into a single scanner. A random access scanner whose scan sequence is specified by a table in random access memory will permit different scan rates on different channels. Generation of this scan table can be a tedious manual task when there are many channels (e.g. 50), when there are more than a few scan rates (e.g. 5), and/or when the ratio of the highest scan rate to the lowest scan rate becomes large (e.g. 100:1). An algorithm is developed which will generate these scan sequences for the random access scanner and implements the algorithm on a digital computer. Application of number theory to the mathematical statement of the problem led to development of several algorithms which were implemented in FORTRAN. The most efficient of these algorithms operates by partitioning the problem into a set of subproblems. Through recursion they solve each subproblem by partitioning it repeatedly into even smaller parts, continuing until a set of simple problems is created. From this process, a pictorial representation or wheel diagram of the problem can be constructed. From the wheel diagram and a description of the original problem, a scan table can be constructed. In addition, the wheel diagram can be used as a method of storing the scan sequence in a smaller amount of memory. The most efficient partitioning algorithm solved most scan table problems in less than a second of CPU time. Some types of problems, however, required as much as a few minutes of CPU time. 26 figures, 2 tables.

  20. Dual antiplatelet response during PCI: VerifyNow P2Y12 predicts myocardial necrosis and thromboxane B2 generation confirms wide variation in aspirin response.

    Science.gov (United States)

    Good, Richard I S; McGarrity, Anne; James, Tina E; Miller, Helen; McConnachie, Alex; Goodall, Alison H; Oldroyd, Keith G

    2015-06-01

    There remains concern that the antiplatelet effects of aspirin and clopidogrel vary between patients and poor responders may be at increased risk of adverse events. However, the optimal method of measuring aspirin and/or clopidogrel response remains unresolved. We compared three methods of measuring clopidogrel response recommended by a recent consensus statement for the European Society of Cardiology, and investigated a novel approach to measuring aspirin response in patients established on both aspirin and clopidogrel. In addition, we investigated whether any of these assays predict peri-procedural myocardial necrosis following percutaneous coronary intervention (PCI). A cross-section of 323 patients attending for PCI was tested for clopidogrel response using VerifyNow P2Y12, VASP Platelet Reactivity Index (VASP-PRI) and whole blood impedance aggregometry (WBPA). Aspirin response was assessed by measuring the residual ability of platelets to generate thromboxane, calculated as the difference between thromboxane B2 levels in serum and plasma, [TxB2]S-P. Peri-procedural myocardial necrosis was determined by a change in troponin I >0.2 μmol/l. Patients demonstrated wide variation in response to both aspirin and clopidogrel. Correlation between VerifyNow P2Y12 and VASP-PRI was good (r=0.702, paspirin response in patients taking dual antiplatelet therapy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. SARAPAN—A Simulated-Annealing-Based Tool to Generate Random Patterned-Channel-Age in CANDU Fuel Management Analyses

    Directory of Open Access Journals (Sweden)

    Doddy Kastanya

    2017-02-01

    Full Text Available In any reactor physics analysis, the instantaneous power distribution in the core can be calculated when the actual bundle-wise burnup distribution is known. Considering the fact that CANDU (Canada Deuterium Uranium utilizes on-power refueling to compensate for the reduction of reactivity due to fuel burnup, in the CANDU fuel management analysis, snapshots of power and burnup distributions can be obtained by simulating and tracking the reactor operation over an extended period using various tools such as the *SIMULATE module of the Reactor Fueling Simulation Program (RFSP code. However, for some studies, such as an evaluation of a conceptual design of a next-generation CANDU reactor, the preferred approach to obtain a snapshot of the power distribution in the core is based on the patterned-channel-age model implemented in the *INSTANTAN module of the RFSP code. The objective of this approach is to obtain a representative snapshot of core conditions quickly. At present, such patterns could be generated by using a program called RANDIS, which is implemented within the *INSTANTAN module. In this work, we present an alternative approach to derive the patterned-channel-age model where a simulated-annealing-based algorithm is used to find such patterns, which produce reasonable power distributions.

  2. Generation of random mutants to improve light-use efficiency of Nannochloropsis gaditana cultures for biofuel production.

    Science.gov (United States)

    Perin, Giorgio; Bellan, Alessandra; Segalla, Anna; Meneghesso, Andrea; Alboresi, Alessandro; Morosinotto, Tomas

    2015-01-01

    The productivity of an algal culture depends on how efficiently it converts sunlight into biomass and lipids. Wild-type algae in their natural environment evolved to compete for light energy and maximize individual cell growth; however, in a photobioreactor, global productivity should be maximized. Improving light use efficiency is one of the primary aims of algae biotechnological research, and genetic engineering can play a major role in attaining this goal. In this work, we generated a collection of Nannochloropsis gaditana mutant strains and screened them for alterations in the photosynthetic apparatus. The selected mutant strains exhibited diverse phenotypes, some of which are potentially beneficial under the specific artificial conditions of a photobioreactor. Particular attention was given to strains showing reduced cellular pigment contents, and further characterization revealed that some of the selected strains exhibited improved photosynthetic activity; in at least one case, this trait corresponded to improved biomass productivity in lab-scale cultures. This work demonstrates that genetic modification of N. gaditana has the potential to generate strains with improved biomass productivity when cultivated under the artificial conditions of a photobioreactor.

  3. Comparison and validation of shallow landslides susceptibility maps generated by bi-variate and multi-variate linear probabilistic GIS-based techniques. A case study from Ribeira Quente Valley (S. Miguel Island, Azores)

    Science.gov (United States)

    Marques, R.; Amaral, P.; Zêzere, J. L.; Queiroz, G.; Goulart, C.

    2009-04-01

    Slope instability research and susceptibility mapping is a fundamental component of hazard assessment and is of extreme importance for risk mitigation, land-use management and emergency planning. Landslide susceptibility zonation has been actively pursued during the last two decades and several methodologies are still being improved. Among all the methods presented in the literature, indirect quantitative probabilistic methods have been extensively used. In this work different linear probabilistic methods, both bi-variate and multi-variate (Informative Value, Fuzzy Logic, Weights of Evidence and Logistic Regression), were used for the computation of the spatial probability of landslide occurrence, using the pixel as mapping unit. The methods used are based on linear relationships between landslides and 9 considered conditioning factors (altimetry, slope angle, exposition, curvature, distance to streams, wetness index, contribution area, lithology and land-use). It was assumed that future landslides will be conditioned by the same factors as past landslides in the study area. The presented work was developed for Ribeira Quente Valley (S. Miguel Island, Azores), a study area of 9,5 km2, mainly composed of volcanic deposits (ash and pumice lapilli) produced by explosive eruptions in Furnas Volcano. This materials associated to the steepness of the slopes (38,9% of the area has slope angles higher than 35°, reaching a maximum of 87,5°), make the area very prone to landslide activity. A total of 1.495 shallow landslides were mapped (at 1:5.000 scale) and included in a GIS database. The total affected area is 401.744 m2 (4,5% of the study area). Most slope movements are translational slides frequently evolving into debris-flows. The landslides are elongated, with maximum length generally equivalent to the slope extent, and their width normally does not exceed 25 m. The failure depth rarely exceeds 1,5 m and the volume is usually smaller than 700 m3. For modelling

  4. Priming psychic and conjuring abilities of a magic demonstration influences event interpretation and random number generation biases

    Directory of Open Access Journals (Sweden)

    Christine eMohr

    2015-01-01

    Full Text Available Magical ideation and belief in the paranormal is considered to represent a trait-like character; people either believe in it or not. Yet, anecdotes indicate that exposure to an anomalous event can turn sceptics into believers. This transformation is likely to be accompanied by altered cognitive functioning such as impaired judgements of event likelihood. Here, we investigated whether the exposure to an anomalous event changes individuals’ explicit traditional (religious and non-traditional (e.g. paranormal beliefs as well as cognitive biases that have previously been associated with non-traditional beliefs, e.g. repetition avoidance when producing random numbers in a mental dice task. In a classroom, 91 students saw a magic demonstration after their psychology lecture. Before the demonstration, half of the students were told that the performance was done respectively by a conjuror (magician group or a psychic (psychic group. The instruction influenced participants’ explanations of the anomalous event. Participants in the magician, as compared to the psychic group, were more likely to explain the event through conjuring abilities while the reverse was true for psychic abilities. Moreover, these explanations correlated positively with their prior traditional and non-traditional beliefs. Finally, we observed that the psychic group showed more repetition avoidance than the magician group, and this effect remained the same regardless of whether assessed before or after the magic demonstration. We conclude that pre-existing beliefs and contextual suggestions both influence people’s interpretations of anomalous events and associated cognitive biases. Beliefs and associated cognitive biases are likely flexible well into adulthood and change with actual life events.

  5. Goal-directed fluid restriction using stroke volume variation and cardiac index during one-lung ventilation: a randomized controlled trial.

    Science.gov (United States)

    Xu, Hui; Shu, Shu-Hua; Wang, Di; Chai, Xiao-Qing; Xie, Yan-Hu; Zhou, Wei-De

    2017-09-01

    Goal-directed therapy confers a strong prognosis in patients undergoing major cardiac or noncardiac surgery. The present study investigated whether intraoperative goal-directed fluid restriction (GDFR) using stroke volume variation (SVV) and cardiac index could improve oxygenation and postoperative outcome in patients undergoing one-lung ventilation (OLV). A Total of 168 patients scheduled for elective thoracoscopic lobectomy under OLV were randomized into the GDFR protocol (group G) or conventional fluid therapy groups (group C). Patients in group C underwent conventional fluid therapy based on mean arterial pressure (MAP), central venous pressure (CVP), and urine volume, whereas those in group G received GDFR protocol associated with the SVV from 10-13% and the cardiac index was controlled at a minimum of 2.5 L/min/m2. The primary outcome variable was PaO2/FiO2. The secondary outcomes were other pulmonary variables and lung mechanics, inflammatory response, the incidence of postoperative pulmonary complications, and the length of hospital stay. During surgery, the PaO2/FiO2 ratio in group G was more than that of group C at 30 and 60 min after OLV, 10 min after re-expansion, and the end of the operation (259±29 vs. 314±34; 253±30 vs. 308±35; 341±34 vs. 394±39; 349±35 vs. 401±39, respectively, all Pmechanics with the initiation of OLV. The incidence of postoperative pulmonary complications such as acute lung injury and pneumonia, and the length of hospital stay were decreased by GDFR protocol as compared to conventional fluid therapy (all P<0.05). However, there were no significant differences between groups with respect to the concentration of serum tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-10 (IL-10). The GDFR protocol based on SVV and cardiac index applied in patients undergoing OLV improves intraoperative pulmonary oxygenation. It can also reduce the postoperative complications and length of hospital stay. However, the

  6. Natural genetic variation in Calligonum Tunisian genus analyzed by ...

    African Journals Online (AJOL)

    Jane

    2011-08-29

    Aug 29, 2011 ... from different regions of Tunisian desert using random amplified polymorphic DNA (RAPD) marker. In total, 46 polymorphic bands ... Key words: Calligonum, genetic diversity, Inter-specific variation, RAPD marker, Tunisian desert. .... generates entirely new variables (axes) and new linear combinations of ...

  7. CLOCK gene variation is associated with incidence of type-2 diabetes and cardiovascular diseases in type-2 diabetic subjects: dietary modulation in the PREDIMED randomized trial.

    Science.gov (United States)

    Corella, Dolores; Asensio, Eva M; Coltell, Oscar; Sorlí, José V; Estruch, Ramón; Martínez-González, Miguel Ángel; Salas-Salvadó, Jordi; Castañer, Olga; Arós, Fernando; Lapetra, José; Serra-Majem, Lluís; Gómez-Gracia, Enrique; Ortega-Azorín, Carolina; Fiol, Miquel; Espino, Javier Díez; Díaz-López, Andrés; Fitó, Montserrat; Ros, Emilio; Ordovás, José M

    2016-01-07

    Circadian rhythms regulate key biological processes influencing metabolic pathways. Disregulation is associated with type 2 diabetes (T2D) and cardiovascular diseases (CVD). Circadian rhythms are generated by a transcriptional autoregulatory feedback loop involving core clock genes. CLOCK (circadian locomotor output cycles protein kaput), one of those core genes, is known to regulate glucose metabolism in rodent models. Cross-sectional studies in humans have reported associations between this locus and obesity, plasma glucose, hypertension and T2D prevalence, supporting its role in cardiovascular risk. However, no longitudinal study has investigated the association between CLOCK gene variation and T2D or CVD incidence. Moreover, although in a previous work we detected a gene-diet interaction between the CLOCK-rs4580704 (C > G) single nucleotide polymorphism (SNP) and monounsaturated (MUFA) intake on insulin resistance, no interventional study has analyzed gene-diet interactions on T2D or CVD outcomes. We analyzed the association between the CLOCK-rs4580704 SNP and incidence of T2D and CVD longitudinally in 7098 PREDIMED trial (ISRCTN35739639) participants after a median 4.8-year follow-up. We also examined modulation by Mediterranean diet (MedDiet) intervention (high in MUFA) on these associations. We observed a significant association between the CLOCK-rs4580704 SNP and T2D incidence in n = 3671 non-T2D PREDIMED participants, with variant allele (G) carriers showing decreased incidence (dominant model) compared with CC homozygotes (HR: 0.69; 95 % CI 0.54-0.87; P = 0.002). This protection was more significant in the MedDiet intervention group (HR: 0.58; 95 % CI 0.43-0.78; P CLOCK-rs4580704 SNP and T2D status on stroke. Thus, only in T2D subjects was CLOCK-rs4580704 SNP associated with stroke risk, G-carriers having decreased risk (HR: 0.61; 95 % CI 0.40-0.94; P = 0.024 versus CC) in the multivariable-adjusted model. In agreement with our previous results showing a

  8. Generation of multi-channel high-speed physical random numbers originated from two chaotic signals of mutually coupled semiconductor lasers

    Science.gov (United States)

    Tang, X.; Wu, Z. M.; Wu, J. G.; Deng, T.; Fan, L.; Zhong, Z. Q.; Chen, J. J.; Xia, G. Q.

    2015-01-01

    We propose and experimentally demonstrate a novel technique to generate multi-channel high-speed physical random numbers (PRNs) by taking two chaotic signal outputs from mutually coupled semiconductor lasers (MC-SLs) as entropy sources. First, through controlling the operation parameters of the MC-SL system, two time-delay signature (TDS) suppressed chaotic signals can be obtained. Next, each of these two chaotic signals is sampled by an 8 bit analog-to-digital converter (ADC) with a sampling rate of 10 GHz, and then a bitwise exclusive-OR (XOR) operation on the corresponding bits in samples of the chaotic signal and its time delayed signal is implemented to obtain 8 bit XOR data. Furthermore, through selecting the five least significant bits (LSBs) of 8 bit XOR data to form 5 bit Boolean sequences, two sets of PRN streams with a rate up to 50 Gbits s-1 are generated and successfully pass the NIST statistical tests. Finally, merging these two sets of 50 Gbits s-1 PRN streams by an interleaving operation, another set of the 100 Gbits s-1 PRN stream, which meets all the quality criteria of NIST statistical tests, is also acquired.

  9. Random thoughts

    Science.gov (United States)

    ajansen; kwhitefoot; panteltje1; edprochak; sudhakar, the

    2014-07-01

    In reply to the physicsworld.com news story “How to make a quantum random-number generator from a mobile phone” (16 May, http://ow.ly/xFiYc, see also p5), which describes a way of delivering random numbers by counting the number of photons that impinge on each of the individual pixels in the camera of a Nokia N9 smartphone.

  10. Balancing selection, random genetic drift, and genetic variation at the major histocompatibility complex in two wild populations of guppies (Poecilia reticulata).

    Science.gov (United States)

    Van Oosterhout, Cock; Joyce, Domino A; Cummings, Stephen M; Blais, Jonatan; Barson, Nicola J; Ramnarine, Indar W; Mohammed, Ryan S; Persad, Nadia; Cable, Joanne

    2006-12-01

    Our understanding of the evolution of genes of the major histocompatibility complex (MHC) is rapidly increasing, but there are still enigmatic questions remaining, particularly regarding the maintenance of high levels of MHC polymorphisms in small, isolated populations. Here, we analyze the genetic variation at eight microsatellite loci and sequence variation at exon 2 of the MHC class IIB (DAB) genes in two wild populations of the Trinidadian guppy, Poecilia reticulata. We compare the genetic variation of a small (Ne, 100) and relatively isolated upland population to that of its much larger (Ne approximately 2400) downstream counterpart. As predicted, microsatellite diversity in the upland population is significantly lower and highly differentiated from the population further downstream. Surprisingly, however, these guppy populations are not differentiated by MHC genetic variation and show very similar levels of allelic richness. Computer simulations indicate that the observed level of genetic variation can be maintained with overdominant selection acting at three DAB loci. The selection coefficients differ dramatically between the upland (s > or = 0.2) and lowland (s guppies in the upland habitat, which has resulted in high levels of MHC diversity being maintained in this population despite considerable genetic drift.

  11. Development and evaluation of a non-ribosomal random PCR and next-generation sequencing based assay for detection and sequencing of hand, foot and mouth disease pathogens.

    Science.gov (United States)

    Nguyen, Anh To; Tran, Thanh Tan; Hoang, Van Minh Tu; Nghiem, Ngoc My; Le, Nhu Nguyen Truc; Le, Thanh Thi My; Phan, Qui Tu; Truong, Khanh Huu; Le, Nhan Nguyen Thanh; Ho, Viet Lu; Do, Viet Chau; Ha, Tuan Manh; Nguyen, Hung Thanh; Nguyen, Chau Van Vinh; Thwaites, Guy; van Doorn, H Rogier; Le, Tan Van

    2016-07-07

    Hand, foot and mouth disease (HFMD) has become a major public health problem across the Asia-Pacific region, and is commonly caused by enterovirus A71 (EV-A71) and coxsackievirus A6 (CV-A6), CV-A10 and CV-A16. Generating pathogen whole-genome sequences is essential for understanding their evolutionary biology. The frequent replacements among EV serotypes and a limited numbers of available whole-genome sequences hinder the development of overlapping PCRs for whole-genome sequencing. We developed and evaluated a non-ribosomal random PCR (rPCR) and next-generation sequencing based assay for sequence-independent whole-genome amplification and sequencing of HFMD pathogens. A total of 16 EV-A71/CV-A6/CV-A10/CV-A16 PCR positive rectal/throat swabs (Cp values: 20.9-33.3) were used for assay evaluation. Our assay evidently outperformed the conventional rPCR in terms of the total number of EV-A71 reads and the percentage of EV-A71 reads: 2.6 % (1275/50,000 reads) vs. 0.1 % (31/50,000) and 6 % (3008/50,000) vs. 0.9 % (433/50,000) for two samples with Cp values of 30 and 26, respectively. Additionally the assay could generate genome sequences with the percentages of coverage of 94-100 % of 4 different enterovirus serotypes in 73 % of the tested samples, representing the first whole-genome sequences of CV-A6/10/16 from Vietnam, and could assign correctly serotyping results in 100 % of 24 tested specimens. In all but three the obtained consensuses of two replicates from the same sample were 100 % identical, suggesting that our assay is highly reproducible. In conclusion, we have successfully developed a non-ribosomal rPCR and next-generation sequencing based assay for sensitive detection and direct whole-genome sequencing of HFMD pathogens from clinical samples.

  12. Unit-specific calibration of Actigraph accelerometers in a mechanical setup - is it worth the effort? The effect on random output variation caused by technical inter-instrument variability in the laboratory and in the field

    DEFF Research Database (Denmark)

    Moeller, Niels C; Korsholm, Lars; Kristensen, Peter L

    2008-01-01

    BACKGROUND: Potentially, unit-specific in-vitro calibration of accelerometers could increase field data quality and study power. However, reduced inter-unit variability would only be important if random instrument variability contributes considerably to the total variation in field data. Therefore...... during free living conditions. RESULTS: Calibration reduced inter-instrument variability considerably in the mechanical setup, both in the MTI instruments (raw SDbetween units = 195 counts*min-1 vs. calibrated SDbetween units = 65 counts*min-1) and in the CSA instruments (raw SDbetween units = 343 counts......*min-1 vs. calibrated SDbetween units = 67 counts*min-1). However, the effect of applying the derived calibration to children's and adolescents' free living physical activity data did not alter the coefficient of variation (CV) (children: CVraw = 30.2% vs. CVcalibrated = 30.4%, adolescents: CVraw = 36...

  13. Randomized clinical study for comparative evaluation of fourth-generation fluoroquinolones with the combination of fortified antibiotics in the treatment of bacterial corneal ulcers.

    Science.gov (United States)

    Shah, Vinit Mahendra; Tandon, Radhika; Satpathy, Gita; Nayak, Niranjan; Chawla, Bhavna; Agarwal, Tushar; Sharma, Namrata; Titiyal, Jeewan S; Vajpayee, Rasik B

    2010-07-01

    Comparative evaluation of efficacy of monotherapy with moxifloxacin (0.5%) or gatifloxacin (0.3%) with combination therapy of cefazolin (5%) and tobramycin (1.3%) in treatment of bacterial corneal ulcers. Patients diagnosed with bacterial keratitis (ulcer diameter 2-8 mm) were randomized to 1 of the 3 treatment groups (tobramycin 1.3% and cefazolin 5%, gatifloxacin 0.3%, or moxifloxacin 0.5%). After obtaining corneal scrapings, assigned study medication was instilled hourly for 48 hours and tapered as per clinical response. Healing of ulcer, duration to cure, adverse reactions, antibiogram profile, treatment failures, final visual acuity, and corneal opacity size were evaluated. A total of 61 patients were enrolled [cefazolin and tobramycin (n = 20), gatifloxacin (n = 21), and moxifloxacin (n = 20)]. Overall, 57 patients (93%) healed on treatment. On comparison of the mean time taken to heal, no statistically significant difference was found among all the 3 treatment groups (P = 0.98). Positive bacterial culture was obtained in only 38 patients (62%). There was no significant difference in the bacterial isolates in each treatment group. There were 4 (7%) treatment failures (perforation or nonhealing ulcer): 1 (5%) each in moxifloxacin and gatifloxacin group and 2 (10%) in fortified antibiotics group. All regimens were well tolerated. The study failed to find a difference in the efficacy of monotherapy with fourth-generation fluoroquinolones in the treatment of bacterial corneal ulcers of 2-8 mm size when compared with combination therapy of fortified antibiotics.

  14. Gain in student understanding of the role of random variation in evolution following teaching intervention based on luria-delbruck experiment.

    Science.gov (United States)

    Robson, Rachel L; Burns, Susan

    2011-01-01

    Undergraduate students in introductory biology classes are typically saddled with pre-existing popular beliefs that impede their ability to learn about biological evolution. One of the most common misconceptions about evolution is that the environment causes advantageous mutations, rather than the correct view that mutations occur randomly and the environment only selects for mutants with advantageous traits. In this study, a significant gain in student understanding of the role of randomness in evolution was observed after students participated in an inquiry-based pedagogical intervention based on the Luria-Delbruck experiment. Questionnaires with isomorphic questions regarding environmental selection among random mutants were administered to study participants (N = 82) in five separate sections of a sophomore-level microbiology class before and after the teaching intervention. Demographic data on each participant was also collected, in a way that preserved anonymity. Repeated measures analysis showed that post-test scores were significantly higher than pre-test scores with regard to the questions about evolution (F(1, 77) = 25.913, p evolution had no significant effect on gain in understanding of this concept. This study indicates that conducting and discussing an experiment about phage resistance in E. coli may improve student understanding of the role of stochastic events in evolution more broadly, as post-test answers showed that students were able to apply the lesson of the Luria-Delbruck experiment to other organisms subjected to other kinds of selection.

  15. Assessment of the genetic diversity in five generations of a ...

    African Journals Online (AJOL)

    Genetic variation among and within five generations of an inbred commercial captive line of Litopenaeus vannamei and genetic distance among them were evaluated by random amplified polymorphic DNA (RAPD), using descriptive and genetic similarity analyses for dominant markers at single- and multi-populational level ...

  16. Mozart: Variations with Dice.

    Science.gov (United States)

    Ruttkay, Zsofia

    1997-01-01

    Discusses an old and quite surprising musical example that provides good challenges in probability theory ranging from practical routine computations to fundamental and philosophical ones, and extended with the engineering design task of generating random numbers. (ASK)

  17. Complications of intravascular catheters in ICU: definitions, incidence and severity. A randomized controlled trial comparing usual transparent dressings versus new-generation dressings (the ADVANCED study).

    Science.gov (United States)

    Günther, Silvia Calviño; Schwebel, Carole; Hamidfar-Roy, Rebecca; Bonadona, Agnès; Lugosi, Maxime; Ara-Somohano, Claire; Minet, Clémence; Potton, Leïla; Cartier, Jean-Charles; Vésin, Aurelien; Chautemps, Magalie; Styfalova, Lenka; Ruckly, Stephane; Timsit, Jean-François

    2016-11-01

    To describe all post-insertion complications involving most used intravascular access, and to determine whether the use of a new-generation transparent dressing (3M™ IV Advanced) might reduce their number and impact on ICU patient outcomes. Patients older than 18, with an expected length of stay ≥48 h and requiring at least one central venous catheter (CVC), arterial catheter (AC), haemodialysis catheter (HDC), pulmonary arterial catheters (PAC) or peripheral venous catheter (PVC) were randomized into two groups: a new-generation transparent dressing, or the hospital's classical transparent dressing, and were followed daily for any infectious and non-infectious complications. Complications were graduated for severity by an independent international multicentre multidisciplinary panel of practitioners using a Delphi process. We included 628 patients, 2214 catheters (873 PVCs, 630 CVCs, 512 ACs and 199 HDCs and PACs) and 4836 dressings. Overall incidence rate was of 60.9/1000 catheter-days. The most common complication was dysfunction (34.6/1000 catheter-days), mainly for PVCs (16/1000 catheter-days) and ACs (12.9/1000 catheter-days). Infectious complications incidence rate in CVCs and ACs was of 14.5/1000, mostly due to colonization (14.2/1000 catheter-days). Thrombosis incidence was of 3.8/1000 catheter-days with severe and very severe complications in 16 cases (1.8/1000 catheter-days) and one thrombosis-related death. 3M™ IV Advanced dressing did not decrease the rate of catheters with at least a minor complication [57.37/1000 vs. 57.52/1000 catheter-days, HR 1.03, CI (0.84-1.27), p = 0.81]. Incidence rates for each single complication remained equivalent: infectious [HR 0.93 (0.62-1.40), p = 0.72], deep thrombosis [HR 0.90 (0.39-2.06), p = 0.80], extravasation and phlebitis [HR 1.40 (0.69-2.82), p = 0.35], accidental removal [1.07 (0.56-2.04), p = 0.84] and dysfunction [HR 1.04 (0.80-1.35), p = 0.79]. The ADVANCED study showed the overall risk

  18. Add-on mirtazapine enhances antipsychotic effect of first generation antipsychotics in schizophrenia: a double-blind, randomized, placebo-controlled trial.

    Science.gov (United States)

    Joffe, Grigori; Terevnikov, Viatcheslav; Joffe, Marina; Stenberg, Jan-Henry; Burkin, Mark; Tiihonen, Jari

    2009-03-01

    Mirtazapine, an antidepressant with a broad spectrum of receptor affinity may, if combined with first generation antipsyhotics (FGAs), improve clinical profile of the FGAs. However, potentiation of the antipsychotic effect by mirtazapine has not been reported thus far. We explored the efficacy of adjunctive mirtazapine on symptoms of schizophrenia in patients having an insufficient response to different FGAs. Schizophrenia-diagnosed patients with a prolonged disease and a history of a poor response to numerous antipsychotics, who were at least moderately ill despite their FGAs treatment, received add-on mirtazapine (n=20) or placebo (n=19) in a 6-week double-blind randomized controlled trial (RCT). The analysis was made on a Modified Intent-to-Treat (MITT) basis with Last Observations Carried Forward (LOCF). Mirtazapine outranged placebo on almost all measures. The clear-cut clinical relevance of this finding was demonstrated by a large effect size of 1.00 (95% CI 0.23-1.67, p=0.003) on the total Positive and Negative Syndrome Scale (PANSS) scores (the primary outcome). The PANSS positive subscale scores decreased by 17.2% with mirtazapine vs. 1.6% with placebo (p<0.001), and the PANSS negative subscale scores by 12% and 3% (p<0.001), correspondingly. This is the first RCT reporting a robust additive antipsychotic effect of an adjunctive antidepressant. Mirtazapine-FGAs combination appears to be a safe, well-tolerated and efficacious treatment option in this challenging population. These findings are important due to the current re-emerging attention to FGAs. The focus of further studies should be expanded to include combinations with or switching to novel antipsychotics, different subpopulations of patients with schizophrenia, finding of optimal doses, and comparison with clozapine.

  19. Self-generation and positivity effects following transcranial random noise stimulation in medial prefrontal cortex: A reality monitoring task in older adults.

    Science.gov (United States)

    Mammarella, Nicola; Di Domenico, Alberto; Palumbo, Rocco; Fairfield, Beth

    2017-06-01

    Activation of medial Prefrontal Cortex (mPFC) has been typically found during reality monitoring tasks (i.e., distinguishing between internal self-generated vs external information). No study, however, has yet investigated whether transcranial Random Noise Stimulation (tRNS) over the mPFC leads to a reduction in reality-monitoring misattributions in aging. In particular, stimulating mPFC should increase the number of cognitive operations engaged while encoding and this distinctive information may help older adults to discriminate between internal and external sources better. In addition, given that older adults are more sensitive to positively-charged information compared to younger adults and that mPFC is typically recruited during encoding of positive stimuli with reference to themselves, activation of mPFC should further sustain source retrieval in older adults. In this double-blind, sham-controlled study, we examined whether tRNS over the mPFC of healthy younger and older adults during encoding enhances subsequent reality monitoring for seen versus imagined emotionally-charged words. Our findings show that tRNS enhances reality monitoring for positively-charged imagined words in the older adult group alone, highlighting the role that mPFC plays in their memory for positive information. In line with the control-based account of positivity effects, our results add evidence about the neurocognitive processes involved in reality monitoring when older adults face emotionally-charged events. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Is the timing of caloric intake associated with variation in diet-induced thermogenesis and in the metabolic pattern? A randomized cross-over study.

    Science.gov (United States)

    Bo, S; Fadda, M; Castiglione, A; Ciccone, G; De Francesco, A; Fedele, D; Guggino, A; Parasiliti Caprino, M; Ferrara, S; Vezio Boggio, M; Mengozzi, G; Ghigo, E; Maccario, M; Broglio, F

    2015-12-01

    Food-induced thermogenesis is generally reported to be higher in the morning, although contrasting results exist because of differences in experimental settings related to the preceding fasting, exercise, sleeping and dieting. To definitively answer to this issue, we compared the calorimetric and metabolic responses to identical meals consumed at 0800 hours and at 2000 hours by healthy volunteers, after standardized diet, physical activity, duration of fast and resting. Twenty subjects (age range 20-35 years, body mass index=19-26 kg m(-)(2)) were enrolled to a randomized cross-over trial. They randomly received the same standard meal in the morning and, 7 days after, in the evening, or vice versa. A 30-min basal calorimetry was performed; a further 60-min calorimetry was done 120-min after the beginning of the meal. Blood samples were drawn every 30-min for 180-min. General linear models, adjusted for period and carry-over, were used to evaluate the 'morning effect', that is, the difference of morning delta (after-meal minus fasting values) minus evening delta (after-meal minus fasting values) of the variables. Fasting resting metabolic rate (RMR) did not change from morning to evening; after-meal RMR values were significantly higher after the morning meal (1916; 95% confidence interval (CI)=1792, 2041 vs 1756; 1648, 1863 kcal; Pmetabolic pattern of healthy individuals. The timing of meals should probably be considered when nutritional recommendations are given.

  1. Freezing regime and trade-offs with water transport efficiency generate variation in xylem structure across diploid populations of Larrea sp. (Zygophyllaceae).

    Science.gov (United States)

    Medeiros, Juliana S; Pockman, William T

    2014-04-01

    The impact of changing temperature regime on plant distributions may depend on the nature of physiological variation among populations. The arid-land genus Larrea spans habitats with a range of freezing frequency in North and South America. We hypothesized that variation in xylem anatomy among populations and species within this genus is driven by plasticity and trade-offs between safety from freeze-thaw embolism and water transport efficiency. We measured vessel density and diameter distributions to predict freeze-thaw embolism and water transport capacity for high and low latitude populations of three Larrea species grown in the field and a greenhouse common garden. Among field-grown L. divaricata, low latitude plants had larger mean vessel diameter and greater predicted freeze-thaw embolism, but higher water transport capacity compared with high latitude plants. Though high latitude L. tridentata and L. nitida had abundant smaller vessels, these plants also produced very large vessels and had semi ring-porous wood structure. Thus, their predicted embolism and water transport capacity were comparable to those of low latitude plants. Differences among field-grown and common-garden-grown plants demonstrate that plasticity contributes to population differentiation in xylem characters, though high latitude L. divaricata exhibited relatively lower plasticity. Our results indicate that a trade-off between transport safety and efficiency contributes substantially to variation in xylem structure within the genus Larrea. In addition, we suggest that xylem plasticity may play a role in negotiating these trade-offs, with implications for responses to future climate change.

  2. Variations of high frequency parameter of heart rate variability following osteopathic manipulative treatment in healthy subjects compared to control group and sham therapy: randomized controlled trial.

    Science.gov (United States)

    Ruffini, Nuria; D'Alessandro, Giandomenico; Mariani, Nicolò; Pollastrelli, Alberto; Cardinali, Lucia; Cerritelli, Francesco

    2015-01-01

    Heart Rate Variability (HRV) indicates how heart rate changes in response to inner and external stimuli. HRV is linked to health status and it is an indirect marker of the autonomic nervous system (ANS) function. To investigate the influence of osteopathic manipulative treatment (OMT) on cardiac autonomic modulation in healthy subjects, compared with sham therapy and control group. Sixty-six healthy subjects, both male and female, were included in the present 3-armed randomized placebo controlled within subject cross-over single blinded study. Participants were asymptomatic adults (26.7 ± 8.4 y, 51% male, BMI 18.5 ± 4.8), both smokers and non-smokers and not on medications. At enrollment subjects were randomized in three groups: A, B, C. Standardized structural evaluation followed by a patient need-based osteopathic treatment was performed in the first session of group A and in the second session of group B. Standardized evaluation followed by a protocoled sham treatment was provided in the second session of group A and in the first session of group B. No intervention was performed in the two sessions of group C, acting as a time-control. The trial was registered on clinicaltrials.gov identifier: NCT01908920. HRV was calculated from electrocardiography before, during and after the intervention, for a total amount time of 25 min and considering frequency domain as well as linear and non-linear methods as outcome measures. OMT engendered a statistically significant increase of parasympathetic activity, as shown by High Frequency power (p ANS activity increasing parasympathetic function and decreasing sympathetic activity, compared to sham therapy and control group.

  3. Variations of high frequency parameter of heart rate variability following osteopathic manipulative treatment in healthy subjects compared to control group and sham therapy: randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Nuria eRuffini

    2015-08-01

    Full Text Available Context: Heart Rate Variability (HRV indicates how heart rate changes in response to inner and external stimuli. HRV is linked to health status and it is an indirect marker of the autonomic nervous system (ANS function. Objective: To investigate the influence of osteopathic manipulative treatment (OMT on ANS activity through changes of High Frequency, a heart rate variability index indicating the parasympathetic activity, in healthy subjects, compared with sham therapy and control group.Methods: Sixty-six healthy subjects, both male and female, were included in the present 3-armed randomized placebo controlled within subject cross-over single blinded study. Participants were asymptomatic adults, both smokers and non-smokers and not on medications. At enrollment subjects were randomized in 3 groups: A, B, C. Standardized structural evaluation followed by a patient need-based osteopathic treatment was performed in the first session of group A and in the second session of group B. Standardized evaluation followed by a protocoled sham treatment was provided in the second session of group A and in the first session of group B. No intervention was performed in the two sessions of group C, acting as a time-control. The trial was registered on clinicaltrials.gov identifier: NCT01908920.Main Outcomes Measures: HRV was calculated from electrocardiography before, during and after the intervention, for a total amount time of 25 minutes.Results: OMT engendered a statistically significant increase of parasympathetic activity, as shown by High Frequency rate (p<0.001, and decrease of sympathetic activity, as revealed by Low Frequency rate (p<0.01; results also showed a reduction of Low Frequency/High Frequency ratio (p<0.001 and Detrended fluctuation scaling exponent (p<0.05. Conclusions: Findings suggested that OMT can influence ANS activity increasing parasympathetic function and decreasing sympathetic activity, compared to sham therapy and control group.

  4. Limited phenotypic variation of hypocalcified amelogenesis imperfecta in a Danish five-generation family with a novel FAM83H nonsense mutation

    DEFF Research Database (Denmark)

    Haubek, Dorte; Gjørup, Hans; Jensen, Lillian Gryesten

    2011-01-01

    BACKGROUND.  Autosomal dominant hypocalcified amelogenesis imperfecta (ADHCAI) is a disease with severe dental manifestations. OBJECTIVES.  The aims were by means of a genome-wide linkage scan to search for the gene underlying the ADHCAI phenotype in a Danish five-generation family and to study t...

  5. Variations of high frequency parameter of heart rate variability following osteopathic manipulative treatment in healthy subjects compared to control group and sham therapy: randomized controlled trial

    Science.gov (United States)

    Ruffini, Nuria; D'Alessandro, Giandomenico; Mariani, Nicolò; Pollastrelli, Alberto; Cardinali, Lucia; Cerritelli, Francesco

    2015-01-01

    Context: Heart Rate Variability (HRV) indicates how heart rate changes in response to inner and external stimuli. HRV is linked to health status and it is an indirect marker of the autonomic nervous system (ANS) function. Objective: To investigate the influence of osteopathic manipulative treatment (OMT) on cardiac autonomic modulation in healthy subjects, compared with sham therapy and control group. Methods: Sixty-six healthy subjects, both male and female, were included in the present 3-armed randomized placebo controlled within subject cross-over single blinded study. Participants were asymptomatic adults (26.7 ± 8.4 y, 51% male, BMI 18.5 ± 4.8), both smokers and non-smokers and not on medications. At enrollment subjects were randomized in three groups: A, B, C. Standardized structural evaluation followed by a patient need-based osteopathic treatment was performed in the first session of group A and in the second session of group B. Standardized evaluation followed by a protocoled sham treatment was provided in the second session of group A and in the first session of group B. No intervention was performed in the two sessions of group C, acting as a time-control. The trial was registered on clinicaltrials.gov identifier: NCT01908920. Main Outcomes Measures: HRV was calculated from electrocardiography before, during and after the intervention, for a total amount time of 25 min and considering frequency domain as well as linear and non-linear methods as outcome measures. Results: OMT engendered a statistically significant increase of parasympathetic activity, as shown by High Frequency power (p < 0.001), expressed in normalized and absolute unit, and possibly decrease of sympathetic activity, as revealed by Low Frequency power (p < 0.01); results also showed a reduction of Low Frequency/High Frequency ratio (p < 0.001) and Detrended fluctuation scaling exponent (p < 0.05). Conclusions: Findings suggested that OMT can influence ANS activity increasing

  6. New Results on the Sum of Gamma Random Variates With Application to the Performance of Wireless Communication Systems over Nakagami-m Fading Channels

    CERN Document Server

    Ansari, Imran Shafique; Alouini, Mohamed-Slim; Kucur, Oğuz

    2012-01-01

    The probability density function (PDF) and cumulative distribution function of the sum of L independent but not necessarily identically distributed gamma variates, applicable to the output statistics of maximal ratio combining (MRC) receiver operating over Nakagami-m fading channels or in other words to the statistical analysis of the scenario where the sum of squared Nakagami-m distributions are user-of-interest, is presented in closed-form in terms of well-known Meijer's G function and easily computable Fox's \\={H} function for integer valued and non-integer valued diversity orders (i.e., m fading parameter of Nakagami fading environment), respectively. Further analysis, particularly on bit error rate via PDF-based approach, too is represented in closed form in terms of Meijer's G function and Fox's \\={H} function for integer valued diversity orders, and extended Fox's \\={H} function ($\\hat{H}$) for non-integer valued diversity orders. The proposed results complement previous elegant results that are either...

  7. On the Sum of Gamma Random Variates With Application to the Performance of Maximal Ratio Combining over Nakagami-m Fading Channels

    KAUST Repository

    Ansari, Imran Shafique

    2012-09-08

    The probability distribution function (PDF) and cumulative density function of the sum of L independent but not necessarily identically distributed gamma variates, applicable to maximal ratio combining receiver outputs or in other words applicable to the performance analysis of diversity combining receivers operating over Nakagami-m fading channels, is presented in closed form in terms of Meijer G-function and Fox H-bar-function for integer valued fading parameters and non-integer valued fading parameters, respectively. Further analysis, particularly on bit error rate via PDF-based approach, too is represented in closed form in terms of Meijer G-function and Fox H-bar-function for integer-order fading parameters, and extended Fox H-bar-function (H-hat) for non-integer-order fading parameters. The proposed results complement previous results that are either evolved in closed-form, or expressed in terms of infinite sums or higher order derivatives of the fading parameter m.

  8. High-resolution arrays reveal burden of copy number variations on Parkinson disease genes associated with increased disease risk in random cohorts.

    Science.gov (United States)

    Murthy, Megha N; Veerappa, Avinash M; Seshachalam, Keshava B; Ramachandra, Nallur B

    2016-09-01

    Parkinson disease (PD) is a neurological disease responsible for a considerable rate of mortality and morbidity in the society. Since the symptoms of the disease appear much later than the actual onset of neuron degeneration, a majority of cases remain undiagnosed until the manifestation of the symptoms. In order to investigate the existence of such susceptibility in the population, we analyzed Copy Number Variation (CNV) influences on PD genes in 1715 individuals from 12 different populations. Overall, 16 CNV-PD genes, 3 known to be causal and 13 associated, were found to be significantly enriched. PARK2, was under heavy burden with ~1% of the population containing CNV in the exonic region. The impact of these genes on the genome and disease pathway was analyzed using several genome analysis tools. Protein interaction network of CNV-PD genes revealed a complex interaction of molecules forming a major hub by the α-Synuclein, whose direct interactors, LRRK2, PARK2 and ATP13A2 are under CNV influence. We hypothesize that CNVs may not be the initiating event in the pathogenesis of PD and remain latent until additional secondary hits are acquired and also propose novel genes that may fall under the PD pathway which contribute in pathogenesis.

  9. Variations of petrophysical properties and spectral induced polarization in response to drainage and imbibition: a study on a correlated random tube network

    Science.gov (United States)

    Maineult, Alexis; Jougnot, Damien; Revil, André

    2018-02-01

    We implement a procedure to simulate the drainage and imbibition in random, 2-D, square networks. We compute the resistivity index, the relative permeability and the characteristic lengths of a correlated network at various saturation states, under the assumption that the surface conductivity can be neglected. These parameters exhibit a hysteretic behaviour. Then, we calculate the spectral induced polarization (SIP) response of the medium, under the assumption that the electrical impedance of each tube follows a local Warburg conductivity model, with identical DC conductivity and chargeability for all the tubes. We evidence that the shape of the SIP spectra depends on the saturation state. The analysis of the evolution of the macroscopic Cole-Cole parameters of the spectra in function of the saturation also behaves hysteretically, except for the Cole-Cole exponent. We also observe a power-law relationship between the macroscopic DC conductivity and time constant and the relative permeability. We also show that the frequency peak of the phase spectra is directly related to the characteristic length and to the relative permeability, underlining the potential interest of SIP measurements for the estimation of the permeability of unsaturated media.

  10. Recurrence of random walks with long-range steps generated by fractional Laplacian matrices on regular networks and simple cubic lattices

    Science.gov (United States)

    Michelitsch, T. M.; Collet, B. A.; Riascos, A. P.; Nowakowski, A. F.; Nicolleau, F. C. G. A.

    2017-12-01

    We analyze a Markovian random walk strategy on undirected regular networks involving power matrix functions of the type L\\frac{α{2}} where L indicates a ‘simple’ Laplacian matrix. We refer to such walks as ‘fractional random walks’ with admissible interval 0 α (recurrent for d≤slantα ) of the lattice. As a consequence, for 0global mean first passage times (Kemeny constant) for the fractional random walk. For an infinite 1D lattice (infinite ring) we obtain for the transient regime 0world properties with the emergence of Lévy flights on large (infinite) lattices.

  11. Random number generators and the Metropolis algorithm: application to various problems in physics and mechanics as an introduction to computational physics

    Energy Technology Data Exchange (ETDEWEB)

    Calvayrac, Florent [Laboratoire de Physique de l' Etat Condense, UMR CNRS 6087 and FR 2575, Universite du Maine, 72085 Le Mans Cedex 9 (France)

    2005-09-01

    We present known and new applications of pseudo random numbers and of the Metropolis algorithm to phenomena of physical and mechanical interest, such as the search of simple clusters isomers with interactive visualization, or vehicle motion planning. The progression towards complicated problems was used with first-year graduate students who wrote most of the programs presented here. We argue that the use of pseudo random numbers in simulation and extrema research programs in teaching numerical methods in physics allows one to get quick programs and physically meaningful and demonstrative results without recurring to the advanced numerical analysis methods.

  12. Variation in homotopic areas' activity and inter-hemispheric intrinsic connectivity with type of language lateralization: an FMRI study of covert sentence generation in 297 healthy volunteers.

    Science.gov (United States)

    Tzourio-Mazoyer, Nathalie; Joliot, M; Marie, D; Mazoyer, B

    2016-06-01

    We investigated the regional correlates of differences in hemispheric lateralization in 297 healthy volunteers [including 153 left-handers (LH)] previously classified into three types of language lateralization according to their hemispheric functional lateralization index measured with fMRI during covert sentence production versus word list production (PRODSENT-LIST): 250 leftward asymmetrical Typicals, 10 rightward asymmetrical Strong-atypicals (only LH), and 37 Ambilaterals with weak lateralization. Using a functionally driven homotopic atlas (AICHA), we compared patterns of regional asymmetry during PRODSENT-LIST in these three groups. Among the 192 homotopic regions of interest (hROIs) of the AICHA atlas, 58 exhibited a significant effect of the type of lateralization on their BOLD signal variation during PRODSENT-LIST. The analyses of patterns of asymmetry of these 58 hROIs showed that (1) hROIs asymmetries in Strong-atypicals were significantly negatively correlated with those observed in Typicals, which indicates that their regional pattern of rightward asymmetries was comparable to the regional pattern of leftward language asymmetries of Typicals; (2) right- and left-handed Typicals had identical profiles, whereas left-handed Ambilaterals exhibited reduced leftward asymmetry as compared either to right-handed Ambilaterals or to Typicals. Moreover, left-handed Ambilaterals pattern of hROIs asymmetries significantly positively correlated with those of both Typicals and Strong-atypicals. In 291 of the participants, we tested the hypothesis that differences in language lateralization were associated with differences in inter-hemispheric connectivity during resting state by measuring their regional homotopic inter-hemispheric intrinsic connectivity coefficient (rHIICC) in 36 of the 58 hROIs known to be connected via the corpus callosum. Mean rHIICCs were negatively correlated with task-induced functional asymmetries, suggesting that enhanced inter

  13. Certified randomness in quantum physics.

    Science.gov (United States)

    Acín, Antonio; Masanes, Lluis

    2016-12-07

    The concept of randomness plays an important part in many disciplines. On the one hand, the question of whether random processes exist is fundamental for our understanding of nature. On the other, randomness is a resource for cryptography, algorithms and simulations. Standard methods for generating randomness rely on assumptions about the devices that are often not valid in practice. However, quantum technologies enable new methods for generating certified randomness, based on the violation of Bell inequalities. These methods are referred to as device-independent because they do not rely on any modelling of the devices. Here we review efforts to design device-independent randomness generators and the associated challenges.

  14. Certified randomness in quantum physics

    Science.gov (United States)

    Acín, Antonio; Masanes, Lluis

    2016-12-01

    The concept of randomness plays an important part in many disciplines. On the one hand, the question of whether random processes exist is fundamental for our understanding of nature. On the other, randomness is a resource for cryptography, algorithms and simulations. Standard methods for generating randomness rely on assumptions about the devices that are often not valid in practice. However, quantum technologies enable new methods for generating certified randomness, based on the violation of Bell inequalities. These methods are referred to as device-independent because they do not rely on any modelling of the devices. Here we review efforts to design device-independent randomness generators and the associated challenges.

  15. RAPD profile variation amongst provenances of neem.

    Science.gov (United States)

    Farooqui, N; Ranade, S A; Sane, P V

    1998-08-01

    Neem, described as a tree for solving global problems, is an evergreen, long-lived, multipurpose tree of the tropics with a wide distribution range in India. It is believed to be highly cross-pollinated. Inter-provenance variations have been reported in neem in case of morphological and physiological characters. Yet no reports about the genetic determinism for these variations are available to our knowledge. In order to have an idea about the extent and/or nature of genetic (DNA) variation in neem, the powerful RAPD technique has been employed. RAPD profiles of 34 accessions/provenances of neem were generated with 200 decamer random primers, of which the data from the 49 primers, that resulted in reproducible amplification products, were considered for analysis. Based on the presence/absence of bands, a similarity matrix was computed. Dendrogram was constructed by UPGMA method based on the pairwise similarities amongst the RAPD profiles. The similarities in RAPD profiles amongst the different DNAs was more than that expected due to the cross-pollinated nature of the tree and furthermore, these more-than-expected similarities were not due to random chance. These results suggest that neem may have a narrow genetic base.

  16. Random Numbers and Quantum Computers

    Science.gov (United States)

    McCartney, Mark; Glass, David

    2002-01-01

    The topic of random numbers is investigated in such a way as to illustrate links between mathematics, physics and computer science. First, the generation of random numbers by a classical computer using the linear congruential generator and logistic map is considered. It is noted that these procedures yield only pseudo-random numbers since…

  17. Age-Related Corresponding Relationships of Controlled Force Exertion Measured by a Computer-Generated Sinusoidal and Quasi-Random Display

    Science.gov (United States)

    Nagasawa, Yoshinori; Demura, Shinichi

    2011-01-01

    This study examined age-group corresponding relationships of the controlled force exertion based on sinusoidal and quasi-random waveforms in 175 right-handed male adults aged 20 to 86 years. The subjects were divided into 3 groups based on age-level: 53 young (mean age 24.6, SD = 3.3 years), 71 middle aged (mean age 44.3, SD = 8.7 years), and 51…

  18. Stochastic process variation in deep-submicron CMOS circuits and algorithms

    CERN Document Server

    Zjajo, Amir

    2014-01-01

    One of the most notable features of nanometer scale CMOS technology is the increasing magnitude of variability of the key device parameters affecting performance of integrated circuits. The growth of variability can be attributed to multiple factors, including the difficulty of manufacturing control, the emergence of new systematic variation-generating mechanisms, and most importantly, the increase in atomic-scale randomness, where device operation must be described as a stochastic process. In addition to wide-sense stationary stochastic device variability and temperature variation, existence of non-stationary stochastic electrical noise associated with fundamental processes in integrated-circuit devices represents an elementary limit on the performance of electronic circuits. In an attempt to address these issues, Stochastic Process Variation in Deep-Submicron CMOS: Circuits and Algorithms offers unique combination of mathematical treatment of random process variation, electrical noise and temperature and ne...

  19. Analysis of diversity in rice ( Oryza sativa L.) using random amplified ...

    African Journals Online (AJOL)

    Molecular markers are useful tool for assessing genetic variations and resolving genotype identity. In the current study, genetic diversity among 20 rice genotypes was assessed using the random amplified polymorphic DNA (RAPD) and simple sequence repeat (SSR). In RAPD analysis, 20 primers generated a total of 116 ...

  20. Metabolic and endocrine adverse effects of second-generation antipsychotics in children and adolescents : A systematic review of randomized, placebo controlled trials and guidelines for clinical practice

    NARCIS (Netherlands)

    De Hert, M.; Dobbelaere, M.; Sheridan, E. M.; Cohen, D.; Correll, C. U.

    Second-generation antipsychotics (SGA) are being used more often than ever before in children and adolescents with psychotic and a wide range of non-psychotic disorders. Several SGA have received regulatory approval for some paediatric indications in various countries, but off-label use is still

  1. Some Difficult-to-pass Tests of Randomness

    Directory of Open Access Journals (Sweden)

    George Marsaglia

    2002-01-01

    Full Text Available We describe three tests of randomness-- tests that many random number generators fail. In particular, all congruential generators-- even those based on a prime modulus-- fail at least one of the tests, as do many simple generators, such as shift register and lagged Fibonacci. On the other hand, generators that pass the three tests seem to pass all the tests in the Diehard Battery of Tests. Note that these tests concern the randomness of a generator's output as a sequence of independent, uniform 32-bit integers. For uses where the output is converted to uniform variates in [0,1, potential flaws of the output as integers will seldom cause problems after the conversion. Most generators seem to be adequate for producing a set of uniform reals in [0,1, but several important applications, notably in cryptography and number theory-- for example, establishing probable primes, complexity of factoring algorithms, random partitions of large integers-- may require satisfactory performance on the kinds of tests we describe here.

  2. A randomized trial found online questionnaires supplemented by postal reminders generated a cost-effective and generalizable sample but don't forget the reminders.

    Science.gov (United States)

    Loban, Amanda; Mandefield, Laura; Hind, Daniel; Bradburn, Mike

    2017-12-01

    The objective of this study was to compare the response rates, data completeness, and representativeness of survey data produced by online and postal surveys. A randomized trial nested within a cohort study in Yorkshire, United Kingdom. Participants were randomized to receive either an electronic (online) survey questionnaire with paper reminder (N = 2,982) or paper questionnaire with electronic reminder (N = 2,855). Response rates were similar for electronic contact and postal contacts (50.9% vs. 49.7%, difference = 1.2%, 95% confidence interval: -1.3% to 3.8%). The characteristics of those responding to the two groups were similar. Participants nevertheless demonstrated an overwhelming preference for postal questionnaires, with the majority responding by post in both groups. Online survey questionnaire systems need to be supplemented with a postal reminder to achieve acceptable uptake, but doing so provides a similar response rate and case mix when compared to postal questionnaires alone. For large surveys, online survey systems may be cost saving. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. FROG - Fingerprinting Genomic Variation Ontology.

    Directory of Open Access Journals (Sweden)

    E Abinaya

    Full Text Available Genetic variations play a crucial role in differential phenotypic outcomes. Given the complexity in establishing this correlation and the enormous data available today, it is imperative to design machine-readable, efficient methods to store, label, search and analyze this data. A semantic approach, FROG: "FingeRprinting Ontology of Genomic variations" is implemented to label variation data, based on its location, function and interactions. FROG has six levels to describe the variation annotation, namely, chromosome, DNA, RNA, protein, variations and interactions. Each level is a conceptual aggregation of logically connected attributes each of which comprises of various properties for the variant. For example, in chromosome level, one of the attributes is location of variation and which has two properties, allosomes or autosomes. Another attribute is variation kind which has four properties, namely, indel, deletion, insertion, substitution. Likewise, there are 48 attributes and 278 properties to capture the variation annotation across six levels. Each property is then assigned a bit score which in turn leads to generation of a binary fingerprint based on the combination of these properties (mostly taken from existing variation ontologies. FROG is a novel and unique method designed for the purpose of labeling the entire variation data generated till date for efficient storage, search and analysis. A web-based platform is designed as a test case for users to navigate sample datasets and generate fingerprints. The platform is available at http://ab-openlab.csir.res.in/frog.

  4. a randomized controlled trial.

    African Journals Online (AJOL)

    milk, only an estimated one -fourth of neonates in India were breastfed within ... standard of care in India and mothers are informed about. 6 months of ... weeks postpartum. A random number sequence was generated using a com- puter program. Block randomization was used with a fixed block size of four. Concealment of ...

  5. Fast and cost-effective single nucleotide polymorphism (SNP) detection in the absence of a reference genome using semideep next-generation Random Amplicon Sequencing (RAMseq).

    Science.gov (United States)

    Bayerl, Helmut; Kraus, Robert H S; Nowak, Carsten; Foerster, Daniel W; Fickel, Joerns; Kuehn, Ralph

    2017-09-15

    Biodiversity has suffered a dramatic global decline during the past decades, and monitoring tools are urgently needed providing data for the development and evaluation of conservation efforts both on a species and on a genetic level. However, in wild species, the assessment of genetic diversity is often hampered by the lack of suitable genetic markers. In this article, we present Random Amplicon Sequencing (RAMseq), a novel approach for fast and cost-effective detection of single nucleotide polymorphisms (SNPs) in nonmodel species by semideep sequencing of random amplicons. By applying RAMseq to the Eurasian otter (Lutra lutra), we identified 238 putative SNPs after quality filtering of all candidate loci and were able to validate 32 of 77 loci tested. In a second step, we evaluated the genotyping performance of these SNP loci in noninvasive samples, one of the most challenging genotyping applications, by comparing it with genotyping results of the same faecal samples at microsatellite markers. We compared (i) polymerase chain reaction (PCR) success rate, (ii) genotyping errors and (iii) Mendelian inheritance (population parameters). SNPs produced a significantly higher PCR success rate (75.5% vs. 65.1%) and lower mean allelic error rate (8.8% vs. 13.3%) than microsatellites, but showed a higher allelic dropout rate (29.7% vs. 19.8%). Genotyping results showed no deviations from Mendelian inheritance in any of the SNP loci. Hence, RAMseq appears to be a valuable tool for the detection of genetic markers in nonmodel species, which is a common challenge in conservation genetic studies. © 2017 John Wiley & Sons Ltd.

  6. Experiencing variation

    DEFF Research Database (Denmark)

    Kobayashi, Sofie; Berge, Maria; Grout, Brian William Wilson

    2017-01-01

    This study contributes towards a better understanding of learning dynamics in doctoral supervision by analysing how learning opportunities are created in the interaction between supervisors and PhD students, using the notion of experiencing variation as a key to learning. Empirically, we have bas...... were discussed, created more complex patterns of variation. Both PhD students and supervisors can learn from this. Understanding of this mechanism that creates learning opportunities can help supervisors develop their competences in supervisory pedagogy....

  7. Molecular Darwinism: the contingency of spontaneous genetic variation.

    Science.gov (United States)

    Arber, Werner

    2011-01-01

    The availability of spontaneously occurring genetic variants is an important driving force of biological evolution. Largely thanks to experimental investigations by microbial geneticists, we know today that several different molecular mechanisms contribute to the overall genetic variations. These mechanisms can be assigned to three natural strategies to generate genetic variants: 1) local sequence changes, 2) intragenomic reshuffling of DNA segments, and 3) acquisition of a segment of foreign DNA. In these processes, specific gene products are involved in cooperation with different nongenetic elements. Some genetic variations occur fully at random along the DNA filaments, others rather with a statistical reproducibility, although at many possible sites. We have to be aware that evolution in natural ecosystems is of higher complexity than under most laboratory conditions, not at least in view of symbiotic associations and the occurrence of horizontal gene transfer. The encountered contingency of genetic variation can possibly best ensure a long-term persistence of life under steadily changing living conditions.

  8. Genetic variation: a laboratory manual

    National Research Council Canada - National Science Library

    Weiner, Michael P; Gabriel, Stacey B; Stephens, J. Claiborne

    2007-01-01

    ... alterations, including copy number variation. The early sections of the manual are devoted to study design and generating genotype data, the use of resources such as HapMap and dbSNP, as well as experimental, statistical, and bioinformatic...

  9. Variational inference & deep learning: A new synthesis

    OpenAIRE

    Kingma, D.P.

    2017-01-01

    In this thesis, Variational Inference and Deep Learning: A New Synthesis, we propose novel solutions to the problems of variational (Bayesian) inference, generative modeling, representation learning, semi-supervised learning, and stochastic optimization

  10. Variational inference & deep learning : A new synthesis

    NARCIS (Netherlands)

    Kingma, D.P.

    2017-01-01

    In this thesis, Variational Inference and Deep Learning: A New Synthesis, we propose novel solutions to the problems of variational (Bayesian) inference, generative modeling, representation learning, semi-supervised learning, and stochastic optimization

  11. Variational inference & deep learning : A new synthesis

    NARCIS (Netherlands)

    Kingma, D.P.

    2017-01-01

    In this thesis, Variational Inference and Deep Learning: A New Synthesis, we propose novel solutions to the problems of variational (Bayesian) inference, generative modeling, representation learning, semi-supervised learning, and stochastic optimization.

  12. Randomization tests

    CERN Document Server

    Edgington, Eugene

    2007-01-01

    Statistical Tests That Do Not Require Random Sampling Randomization Tests Numerical Examples Randomization Tests and Nonrandom Samples The Prevalence of Nonrandom Samples in Experiments The Irrelevance of Random Samples for the Typical Experiment Generalizing from Nonrandom Samples Intelligibility Respect for the Validity of Randomization Tests Versatility Practicality Precursors of Randomization Tests Other Applications of Permutation Tests Questions and Exercises Notes References Randomized Experiments Unique Benefits of Experiments Experimentation without Mani

  13. Neurological adverse events of new generation sodium blocker antiepileptic drugs. Meta-analysis of randomized, double-blinded studies with eslicarbazepine acetate, lacosamide and oxcarbazepine.

    Science.gov (United States)

    Zaccara, Gaetano; Giovannelli, Fabio; Maratea, Dario; Fadda, Valeria; Verrotti, Alberto

    2013-09-01

    Analysis of overall tolerability and neurological adverse effects (AEs) of eslicarbazepine acetate (ESL), lacosamide (LCM) and oxcarbazepine (OXC) from double-blind, placebo-controlled trials. Indirect comparisons of patients withdrawing because of AEs, and the incidence of some vestibulocerebellar AEs between these three antiepileptic dugs (AEDs). We searched MEDLINE for all randomized, double-blind, placebo-controlled trials investigating therapeutic effects of fixed oral doses of ESL, LCM and OXC in patients with drug resistant epilepsy. Withdrawal rate due to AEs, percentages of patients with serious AEs, and the proportion of patients experiencing any neurological AE, nausea and vomiting were assessed for their association with the experimental drug. Analyses were performed between recommended daily doses of each AED according to the approved summary of product characteristics (SPC). Risk differences were used to evaluate the association of any AE [99% confidence intervals (CIs)] or study withdrawals because of AEs (95% CIs) with the experimental drug. Indirect comparisons between withdrawal rate and AEs dizziness, coordination abnormal/ataxia and diplopia were estimated according to network meta-analysis (Net-MA). Eight randomized, placebo-controlled, double-blind trials (4 with ESL, 3 with LCM, and 1 with OXC) were included in our analysis. At high doses (OXC 1200mg, ESL 1200mg and LCM 400mg) there was an increased risk of AE-related study withdrawals compared to placebo for all drugs. Several AEs were associated with the experimental drug. Both number and frequency of AEs were dose-related. At high recommended doses, patients treated with OXC withdrew from the experimental treatment significantly more frequently than patients treated with ESL and LCM. Furthermore, the AEs coordination abnormal/ataxia and diplopia were significantly more frequently observed in patients treated with OXC compared to patients treated with LCM and ESL. The overall tolerability

  14. Ladder Variational Autoencoder

    DEFF Research Database (Denmark)

    Sønderby, Casper Kaae; Raiko, Tapani; Maaløe, Lars

    2016-01-01

    Variational autoencoders are powerful models for unsupervised learning. However deep models with several layers of dependent stochastic variables are difficult to train which limits the improvements obtained using these highly expressive models. We propose a new inference model, the Ladder...... Variational Autoencoder, that recursively corrects the generative distribution by a data dependent approximate likelihood in a process resembling the recently proposed Ladder Network. We show that this model provides state of the art predictive log-likelihood and tighter log-likelihood lower bound compared...

  15. Ladder variational autoencoders

    DEFF Research Database (Denmark)

    Sønderby, Casper Kaae; Raiko, Tapani; Maaløe, Lars

    2016-01-01

    Variational autoencoders are powerful models for unsupervised learning. However deep models with several layers of dependent stochastic variables are difficult to train which limits the improvements obtained using these highly expressive models. We propose a new inference model, the Ladder...... Variational Autoencoder, that recursively corrects the generative distribution by a data dependent approximate likelihood in a process resembling the recently proposed Ladder Network. We show that this model provides state of the art predictive log-likelihood and tighter log-likelihood lower bound compared...

  16. The Monty Python Method for Generating Gamma Variables

    Directory of Open Access Journals (Sweden)

    George Marsaglia

    1999-01-01

    Full Text Available The Monty Python Method for generating random variables takes a decreasing density, cuts it into three pieces, then, using area-preserving transformations, folds it into a rectangle of area 1. A random point (x,y from that rectangle is used to provide a variate from the given density, most of the time as itself or a linear function of x . The decreasing density is usually the right half of a symmetric density. The Monty Python method has provided short and fast generators for normal, t and von Mises densities, requiring, on the average, from 1.5 to 1.8 uniform variables. In this article, we apply the method to non-symmetric densities, particularly the important gamma densities. We lose some of the speed and simplicity of the symmetric densities, but still get a method for γα variates that is simple and fast enough to provide beta variates in the form γa/(γa+γb. We use an average of less than 1.7 uniform variates to produce a gamma variate whenever α ≥ 1 . Implementation is simpler and from three to five times as fast as a recent method reputed to be the best for changing α's.

  17. Variational analysis

    CERN Document Server

    Rockafellar, R Tyrrell

    1998-01-01

    From its origins in the minimization of integral functionals, the notion of 'variations' has evolved greatly in connection with applications in optimization, equilibrium, and control. It refers not only to constrained movement away from a point, but also to modes of perturbation and approximation that are best describable by 'set convergence', variational convergence of functions and the like. This book develops a unified framework and, in finite dimension, provides a detailed exposition of variational geometry and subdifferential calculus in their current forms beyond classical and convex analysis. Also covered are set-convergence, set-valued mappings, epi-convergence, duality, maximal monotone mappings, second-order subderivatives, measurable selections and normal integrands. The changes in this 3rd printing mainly concern various typographical corrections, and reference omissions that came to light in the previous printings. Many of these reached the authors' notice through their own re-reading, that of th...

  18. Variational principles

    CERN Document Server

    Moiseiwitsch, B L

    2004-01-01

    This graduate-level text's primary objective is to demonstrate the expression of the equations of the various branches of mathematical physics in the succinct and elegant form of variational principles (and thereby illuminate their interrelationship). Its related intentions are to show how variational principles may be employed to determine the discrete eigenvalues for stationary state problems and to illustrate how to find the values of quantities (such as the phase shifts) that arise in the theory of scattering. Chapter-by-chapter treatment consists of analytical dynamics; optics, wave mecha

  19. Variation and Synthetic Speech

    CERN Document Server

    Miller, C; Massey, N; Miller, Corey; Karaali, Orhan; Massey, Noel

    1997-01-01

    We describe the approach to linguistic variation taken by the Motorola speech synthesizer. A pan-dialectal pronunciation dictionary is described, which serves as the training data for a neural network based letter-to-sound converter. Subsequent to dictionary retrieval or letter-to-sound generation, pronunciations are submitted a neural network based postlexical module. The postlexical module has been trained on aligned dictionary pronunciations and hand-labeled narrow phonetic transcriptions. This architecture permits the learning of individual postlexical variation, and can be retrained for each speaker whose voice is being modeled for synthesis. Learning variation in this way can result in greater naturalness for the synthetic speech that is produced by the system.

  20. Impact of Reducing Polarimetric SAR Input on the Uncertainty of Crop Classifications Based on the Random Forests Algorithm

    DEFF Research Database (Denmark)

    Loosvelt, Lien; Peters, Jan; Skriver, Henning

    2012-01-01

    acquired by the Danish EMISAR on four dates within the period April to July in 1998. The predictive capacity of each feature is analyzed by the importance score generated by random forests (RF). Results show that according to the variation in importance score over time, a distinction can be made between...

  1. Random Numbers from Astronomical Imaging

    OpenAIRE

    Pimbblet, Kevin A.; Bulmer, Michael

    2004-01-01

    This article describes a method to turn astronomical imaging into a random number generator by using the positions of incident cosmic rays and hot pixels to generate bit streams. We subject the resultant bit streams to a battery of standard benchmark statistical tests for randomness and show that these bit streams are statistically the same as a perfect random bit stream. Strategies for improving and building upon this method are outlined.

  2. Autonomous Byte Stream Randomizer

    Science.gov (United States)

    Paloulian, George K.; Woo, Simon S.; Chow, Edward T.

    2013-01-01

    Net-centric networking environments are often faced with limited resources and must utilize bandwidth as efficiently as possible. In networking environments that span wide areas, the data transmission has to be efficient without any redundant or exuberant metadata. The Autonomous Byte Stream Randomizer software provides an extra level of security on top of existing data encryption methods. Randomizing the data s byte stream adds an extra layer to existing data protection methods, thus making it harder for an attacker to decrypt protected data. Based on a generated crypto-graphically secure random seed, a random sequence of numbers is used to intelligently and efficiently swap the organization of bytes in data using the unbiased and memory-efficient in-place Fisher-Yates shuffle method. Swapping bytes and reorganizing the crucial structure of the byte data renders the data file unreadable and leaves the data in a deconstructed state. This deconstruction adds an extra level of security requiring the byte stream to be reconstructed with the random seed in order to be readable. Once the data byte stream has been randomized, the software enables the data to be distributed to N nodes in an environment. Each piece of the data in randomized and distributed form is a separate entity unreadable on its own right, but when combined with all N pieces, is able to be reconstructed back to one. Reconstruction requires possession of the key used for randomizing the bytes, leading to the generation of the same cryptographically secure random sequence of numbers used to randomize the data. This software is a cornerstone capability possessing the ability to generate the same cryptographically secure sequence on different machines and time intervals, thus allowing this software to be used more heavily in net-centric environments where data transfer bandwidth is limited.

  3. Bifurcation and Synchronization of Two Coupled Generators

    Science.gov (United States)

    Martynyuk, A. À.; Nikitina, N. V.

    2017-03-01

    Coupled generators having the property of multistability (one generator with exponential inertial nonlinearity and Chou generator) are considered. New oscillation conditions occurring under synchronization are established using the characteristic equation for the system of variational equations

  4. Random Number Generation: A Practitioner's Overview

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    About the speaker Dr. Mascagni is full professor at Florida State University, where he runs a research group consisting of post-doctoral associates, graduate students, and undergraduate workers. The areas they work on are p...

  5. Random Number Generation for High Performance Computing

    Science.gov (United States)

    2015-01-01

    issued patent and patent application are included as appendices in the pdf file accompanying this final report. Received Book TOTAL: Received Book Chapter...plan, the product of research undertaken by Silicon Informatics, KEYW Corporation and the UTSA Center for Innovation and Technology Entrepreneurship

  6. Generation and Analysis of Random Waves

    DEFF Research Database (Denmark)

    Liu, Zhou; Frigaard, Peter

    Sea waves are the most important phenomenon to be considered in the design of coastal and offshore structures. It should be stressed that, even though all contents in the book are related to sea waves, they have a broader application in practice. For example, the extreme theory has also been......-requirement for the book is the knowledge of linear wave theory....

  7. A Random Word Generator for Pronounceable Passwords

    Science.gov (United States)

    1975-11-01

    gipromso gip-rom-so fitwif fi-twif gadmajbu gad-maj-bu girtwu gir -twu fiufrase fi-u-frase gaibci gaib-ci giwarnn gi-warnn fleac fleac gairgy gairg-y...mu ryu-a-jir ryu-wa ry-wict-fi sad -jip sa-dol sa-hoarv-y sa-huv sal-no-du san-fo sa-nomt sat-nan sav-ki saw-to-yad says-bu sceelt-fu

  8. Simulating the parameters of multi-modal groundwater residence-time distributions using parsimonious and automatically generated numerical models that incorporate spatial variation of drainage density, aquifer thickness, recharge, and aquifer properties

    Science.gov (United States)

    Starn, J. J.; Belitz, K.; Kauffman, L. J.; Yager, R. M.

    2016-12-01

    Groundwater residence-time distributions (RTDs) are important for assessing groundwater vulnerability. Two methods for calculating RTDs are common: lumped parameter models (LPMs) and distributed numerical models (DNMs). Model parameters in either approach can be determined by fitting to tracer data. LPMs represent simple flow systems and have few parameters; however, they may not be appropriate where internal aquifer processes are important, in transient flow systems, or in spatially complex flow systems. DNMs are not constrained by assumptions of uniform aquifer thickness, recharge, or aquifer properties, but are time-consuming and expensive to construct. This approach seeks to bridge the gap between LPMs and DNMs. Generalized DNMs (GDNMs) are created having a small number of parameters compared to typical DNMs. GDNMs are created automatically at the HUC8 scale based on nationally available data sets and incorporate spatial variation not present in LPMs such as drainage density, aquifer thickness, recharge, and aquifer properties. Typical creation time from a model domain shapefile to a "calibrated" model is about 10 minutes. GDNMs were created in various hydrogeologic settings in the glaciated U.S. where age-tracer data exist. GDNMs are "calibrated" by automatically adjusting hydraulic conductivity in a small number of zones to minimize the fraction of cells where the simulated water table is above land surface and below perennial streams. RTDs are calculated for groundwater basins, public-supply wells, and stream reaches using particle tracking. RTDs, which often are multi-modal, are summarized by fitting statistical distributions (additive combinations of Weibull, gamma, or inverse Gaussian) to particle RTDs. GDNMs are tested by comparing simulated and observed heads and by applying convolution to generate breakthrough curves for tracers that can be compared to observed concentrations. GDNMs also are compared to highly distributed DNMs from other sources. The

  9. Short Duration vs Standard Duration of Dual-Antiplatelet Therapy After Percutaneous Coronary Intervention With Second-Generation Drug-Eluting Stents - A Systematic Review, Meta-Analysis, and Meta-Regression Analysis of Randomized Controlled Trials.

    Science.gov (United States)

    Wassef, Anthony W A; Khafaji, Hadi; Syed, Ishba; Yan, Andrew T; Udell, Jacob A; Goodman, Shaun G; Cheema, Asim N; Bagai, Akshay

    2016-12-01

    Current guidelines recommend 12 months of dual-antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) with drug-eluting stent (DES) implantation. Whether the duration of DAPT can be safely shortened with use of second-generation DESs is unclear. We conducted a meta-analysis of randomized controlled trials comparing short duration (SD) (3-6 months) with standard longer duration (LD) (≥12 months) DAPT in patients treated with primarily second-generation DES implantation. Meta-regression was performed to explore the relationship between acute coronary syndrome (ACS) and the effect of DAPT duration. Six studies were included, with 12,752/13,928 (91.5%) patients receiving second-generation DESs. A total of 5367 patients (39%) had PCI in the setting of ACS. There was no difference in all-cause mortality (1.1% vs 1.2%; odds ratio [OR], 0.86; 95% confidence interval [CI], 0.63-1.18; P=.36) or cardiac mortality (0.9% vs 1.0%; OR, 0.92; 95% CI, 0.61-1.39; P=.69) with SD-DAPT vs LD-DAPT, respectively. Definite/probable stent thrombosis (0.5% vs 0.3%; OR, 1.33; 95% CI, 0.75-2.34; P=.51), myocardial infarction (1.5% vs 1.3%; OR, 1.17; 95% CI, 0.88-1.56; P=.29), and stroke (0.4% vs 0.4%; OR, 1.04; 95% CI, 0.60-1.81; P=.88) were similar between the groups. Compared with LD-DAPT, SD-DAPT was associated with lower clinically significant bleeding (0.9% vs 1.4%; OR, 0.64; 95% CI, 0.46-0.89; P=.01). Meta-regression analysis showed no significant association between the proportion of ACS patients in trials and duration of DAPT for the outcomes of mortality (P=.95), myocardial infarction (P=.98), or stent thrombosis (P=.89). In low-risk patients treated with contemporary second-generation DES implantation, SD-DAPT has similar rates of mortality, myocardial infarction, and stent thrombosis, with lower rates of bleeding compared with LD-DAPT.

  10. Simulation of random events for adaptive control systems calibration

    Directory of Open Access Journals (Sweden)

    Drăgoi Mircea Viorel

    2017-01-01

    Full Text Available The paper deals with a mathematical model that simulates the random occurrence of events during cutting processes by milling. The evolution of certain parameters that typify the cutting processes depends on predictable and non-predictable variables. In this context, either the material hardness that varies in different sides of billet, or cutting depth, can act as non-predictable variables. In order to design a response in terms of cutting parameters to non-predictable variations of inputs, a simulation of such phenomena is very useful. A mathematical model that generates random events, both in terms of non-uniform frequency and intensity is here described. A virtual instrument built in LabVIEW generates (pseudo random events based on a combination of random numbers, as the evolution of the simulated process to be much like a real one. Furthermore the user of virtual instrument can generate himself events at certain moments and of certain intensity. This can be a useful tool to study the algorithms of designing the response which should re-balance the process within adaptive control systems.

  11. Selectivity and sparseness in randomly connected balanced networks.

    Directory of Open Access Journals (Sweden)

    Cengiz Pehlevan

    Full Text Available Neurons in sensory cortex show stimulus selectivity and sparse population response, even in cases where no strong functionally specific structure in connectivity can be detected. This raises the question whether selectivity and sparseness can be generated and maintained in randomly connected networks. We consider a recurrent network of excitatory and inhibitory spiking neurons with random connectivity, driven by random projections from an input layer of stimulus selective neurons. In this architecture, the stimulus-to-stimulus and neuron-to-neuron modulation of total synaptic input is weak compared to the mean input. Surprisingly, we show that in the balanced state the network can still support high stimulus selectivity and sparse population response. In the balanced state, strong synapses amplify the variation in synaptic input and recurrent inhibition cancels the mean. Functional specificity in connectivity emerges due to the inhomogeneity caused by the generative statistical rule used to build the network. We further elucidate the mechanism behind and evaluate the effects of model parameters on population sparseness and stimulus selectivity. Network response to mixtures of stimuli is investigated. It is shown that a balanced state with unselective inhibition can be achieved with densely connected input to inhibitory population. Balanced networks exhibit the "paradoxical" effect: an increase in excitatory drive to inhibition leads to decreased inhibitory population firing rate. We compare and contrast selectivity and sparseness generated by the balanced network to randomly connected unbalanced networks. Finally, we discuss our results in light of experiments.

  12. Insights into pre-reversal paleosecular variation from stochastic models

    Directory of Open Access Journals (Sweden)

    Klaudio ePeqini

    2015-09-01

    Full Text Available To provide insights on the paleosecular variation of the geomagnetic field and the mechanism of reversals, long time series of the dipolar magnetic moment are generated by two different stochastic models, known as the domino model and the inhomogeneous Lebovitz disk dynamo model, with initial values taken from the from paleomagnetic data. The former model considers mutual interactions of N macrospins embedded in a uniformly rotating medium, where random forcing and dissipation act on each macrospin. With an appropriate set of the model’s parameters values, the series generated by this model have similar statistical behaviour to the time series of the SHA.DIF.14K model. The latter model is an extension of the classical two-disk Rikitake model, considering N dynamo elements with appropriate interactions between them.We varied the parameters set of both models aiming at generating suitable time series with behaviour similar to the long time series of recent secular variation (SV. Such series are then extended to the near future, obtaining reversals in both cases of models. The analysis of the time series generated by simulating the models show that the reversals appears after a persistent period of low intensity geomagnetic field, as it is occurring in the present times.

  13. Variation-aware advanced CMOS devices and SRAM

    CERN Document Server

    Shin, Changhwan

    2016-01-01

    This book provides a comprehensive overview of contemporary issues in complementary metal-oxide semiconductor (CMOS) device design, describing how to overcome process-induced random variations such as line-edge-roughness, random-dopant-fluctuation, and work-function variation, and the applications of novel CMOS devices to cache memory (or Static Random Access Memory, SRAM). The author places emphasis on the physical understanding of process-induced random variation as well as the introduction of novel CMOS device structures and their application to SRAM. The book outlines the technical predicament facing state-of-the-art CMOS technology development, due to the effect of ever-increasing process-induced random/intrinsic variation in transistor performance at the sub-30-nm technology nodes. Therefore, the physical understanding of process-induced random/intrinsic variations and the technical solutions to address these issues plays a key role in new CMOS technology development. This book aims to provide the reade...

  14. Random recursive trees and the elephant random walk

    Science.gov (United States)

    Kürsten, Rüdiger

    2016-03-01

    One class of random walks with infinite memory, so-called elephant random walks, are simple models describing anomalous diffusion. We present a surprising connection between these models and bond percolation on random recursive trees. We use a coupling between the two models to translate results from elephant random walks to the percolation process. We calculate, besides other quantities, exact expressions for the first and the second moment of the root cluster size and of the number of nodes in child clusters of the first generation. We further introduce another model, the skew elephant random walk, and calculate the first and second moment of this process.

  15. Electric generators: Roesel

    Energy Technology Data Exchange (ETDEWEB)

    Segaser, C.L.

    1977-04-01

    A new and unique type of electrical generator is described that will provide constant frequency output (within 0.01% or better) regardless of rotational speed variations. It accomplishes this with no added bulk over conventional generators, and with excellent efficiency. The same principle that permits constant frequency output also provides the means for output voltage regulation with varying drive speed and/or varying load. Onsite power generation aspects of the Integrated Community Energy Systems (ICES) concept include the requirement to follow community electric loads and the possible use of internal combustion piston engines with waste heat recovery to drive electric generators. The diesel engine is a prime candidate from commercially available technologies for which part-load shaft efficiency is better at reduced speed than for constant-speed operation required by conventional AC generators. The unique characteristics of the Roesel generator allow prime mover speed to decrease with load and offer improved engine-generator system efficiency in ICES applications.

  16. Procedural facade variations from a single layout

    KAUST Repository

    Bao, Fan

    2013-01-01

    We introduce a framework to generate many variations of a facade design that look similar to a given facade layout. Starting from an input image, the facade is hierarchically segmented and labeled with a collection of manual and automatic tools. The user can then model constraints that should be maintained in any variation of the input facade design. Subsequently, facade variations are generated for different facade sizes, where multiple variations can be produced for a certain size. Computing such new facade variations has many unique challenges, and we propose a new algorithm based on interleaving heuristic search and quadratic programming. In contrast to most previous work, we focus on the generation of new design variations and not on the automatic analysis of the input\\'s structure. Adding a modeling step with the user in the loop ensures that our results routinely are of high quality. © 2013 ACM.

  17. Auxiliary Deep Generative Models

    DEFF Research Database (Denmark)

    Maaløe, Lars; Sønderby, Casper Kaae; Sønderby, Søren Kaae

    2016-01-01

    Deep generative models parameterized by neural networks have recently achieved state-of-the-art performance in unsupervised and semi-supervised learning. We extend deep generative models with auxiliary variables which improves the variational approximation. The auxiliary variables leave...... the generative model unchanged but make the variational distribution more expressive. Inspired by the structure of the auxiliary variable we also propose a model with two stochastic layers and skip connections. Our findings suggest that more expressive and properly specified deep generative models converge...... faster with better results. We show state-of-the-art performance within semi-supervised learning on MNIST (0.96%), SVHN (16.61%) and NORB (9.40%) datasets....

  18. Epigenetic randomness, complexity and singularity of human iris patterns.

    Science.gov (United States)

    Daugman, J; Downing, C

    2001-08-22

    We investigated the randomness and uniqueness of human iris patterns by mathematically comparing 2.3 million different pairs of eye images. The phase structure of each iris pattern was extracted by demodulation with quadrature wavelets spanning several scales of analysis. The resulting distribution of phase sequence variation among different eyes was precisely binomial, revealing 244 independent degrees of freedom. This amount of statistical variability corresponds to an entropy (information density) of about 3.2 bits mm(-2) over the iris. It implies that the probability of two different irides agreeing by chance in more than 70% of their phase sequence is about one in 7 billion. We also compared images of genetically identical irides, from the left and right eyes of 324 persons, and from monozygotic twins. Their relative phase sequence variation generated the same statistical distribution as did unrelated eyes. This indicates that apart from overall form and colour, iris patterns are determined epigenetically by random events in the morphogenesis of this tissue. The resulting diversity, and the combinatorial complexity created by so many dimensions of random variation, mean that the failure of a simple test of statistical independence performed on iris patterns can serve as a reliable rapid basis for automatic personal identification.

  19. Natural Language Generation

    Science.gov (United States)

    1992-12-01

    and generate human language into and from computer-internal format in restricted domains, and since the cost of teaching people specialized computer...shape). Most of the carrier channels can be made to vary their presentee . value in time. Time variation 60 ’-xlwý rip~ 777 / can be seen as an...Generation, Edinburgh. [Charniak & Shimony 90] Charniak, E. and Shimony, S.E. 1990. Probabilistic Semantics for Cost Based Abduction. In Proceedings

  20. A phylogenetic analysis of Schistosoma haematobium group species based on randomly amplified polymorphic DNA.

    Science.gov (United States)

    Kaukas, A; Dias Neto, E; Simpson, A J; Southgate, V R; Rollinson, D

    1994-04-01

    Randomly amplified polymorphic DNA (RAPD) profiles were produced using four oligonucleotide primers with genomic DNA from 15 isolates of schistosome. Both inter- and intraspecific variation were noted. Intraspecific variation was greater for two species of the S. haematobium group (S. haematobium and S. intercalatum) than for S. mansoni. The inferred phylogeny placed S. curassoni and S. bovis as sister groups to S. mansoni-S. rodhaini group. S. mattheei and S. leiperi formed a separate lineage. The results confirm that RAPD profiles may be used for both strain and species differentiation and for the generation of phylogenetic trees.

  1. Measuring signal generators theory & design

    CERN Document Server

    Rybin, Yuriy K

    2014-01-01

    The book brings together the following issues: Theory of deterministic, random and discrete signals reproducible in oscillatory systems of generators; Generation of periodic signals with a specified spectrum, harmonic distortion factor and random signals with specified probability density function and spectral density; Synthesis of oscillatory system structures; Analysis of oscillatory systems with non-linear elements and oscillation amplitude stabilization systems; It considers the conditions and criteria of steady-state modes in signal generators on active four-pole elements with unidirectional and bidirectional transmission of signals and on two-pole elements; analogues of Barkhausen criteria; Optimization of oscillatory system structures by harmonic distortion level, minimization of a frequency error and set-up time of the steady state mode; Theory of construction of random signal generators; Construction of discrete and digital signal generators; Practical design of main units of generators; Practical bl...

  2. Generating Units

    Data.gov (United States)

    Department of Homeland Security — Generating Units are any combination of physically connected generators, reactors, boilers, combustion turbines, and other prime movers operated together to produce...

  3. Genetic variation in genes affecting milk composition and quality

    DEFF Research Database (Denmark)

    Bertelsen, Henriette Pasgaard

    In the past decade major advances in next generation sequencing technologies have provided new opportuneties for the detection of genetic variation. Combining the knowlegde of genetic variation with phenotypic distributions provides considerable possibilites for detection of candidate genes....... In addition, exploring genetic variation related to the major milk proteins of bovine milk indntified genetic variations with possitive effects on milk coagulation...

  4. Generational diversity.

    Science.gov (United States)

    Kramer, Linda W

    2010-01-01

    Generational diversity has proven challenges for nurse leaders, and generational values may influence ideas about work and career planning. This article discusses generational gaps, influencing factors and support, and the various generational groups present in today's workplace as well as the consequences of need addressing these issues. The article ends with a discussion of possible solutions.

  5. Characterization of nonstationary random processes

    Energy Technology Data Exchange (ETDEWEB)

    Paez, T.L.

    1985-01-01

    Current methods for shock test specification and shock testing treat the shock environment as a deterministic source. The present study proposes to treat shock sources as nonstationary random processes. A model for a realistic nonstationary random process shock source is specified, and the effect of variation of parameters in the shock source is shown. A method for estimating the parameters of the random process is established, and some numerical examples show that the method yields reasonable results. The use of this model in shock testing is discussed.

  6. Female discrimination thresholds frequently exceed local male display variation: implications for mate choice dynamics and sexual selection.

    Science.gov (United States)

    Höbel, G

    2016-03-01

    Among the factors that can influence female mate choice decisions is the degree to which females differentiate among similar displays: as differences decrease, females are expected to eventually stop discriminating. This discrimination threshold, in conjunction with the magnitude of male trait variation females regularly encounter while making mate choice decisions, may have important consequences for sexual selection. If local display variation is above the discrimination threshold, female preferences should translate into higher mating success for the more attractive male. But if display variation is frequently below the threshold, the resulting increased pattern of random mating may obscure the existence of female mate choice. I investigated the interplay between female discrimination and male display variation in green treefrogs (Hyla cinerea) and found that call trait differences between nearest neighbour males were frequently smaller than what females are expected to discriminate. This finding has two important consequences for our understanding of sexual selection in the wild: first, low display variation should weaken the strength of selection on male display traits, but the direction of selection should mirror the one predicted from females choice trials. Second, caution is needed when interpreting data on realized mating success in the wild: a pattern of random mating with respect to male display traits does not always mean that female preferences are weak or that conditions are too challenging for females to express their preferences. Rather, insufficient display variation can generate the same pattern. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

  7. Eastern Renewable Generation Integration Study

    Energy Technology Data Exchange (ETDEWEB)

    Bloom, Aaron [National Renewable Energy Lab. (NREL), Golden, CO (United States); Townsend, Aaron [National Renewable Energy Lab. (NREL), Golden, CO (United States); Palchak, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Novacheck, Joshua [National Renewable Energy Lab. (NREL), Golden, CO (United States); King, Jack [RePPAE LLC, Wexford, PA (United States); Barrows, Clayton [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ibanez, Eduardo [GE Energy, Denver, CO (United States); O' Connell, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jordan, Gary [GE Energy, Denver, CO (United States); Roberts, Billy [National Renewable Energy Lab. (NREL), Golden, CO (United States); Draxl, Caroline [National Renewable Energy Lab. (NREL), Golden, CO (United States); Gruchalla, Kenny [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-08-01

    The Eastern Interconnection (EI) is one of the largest power systems in the world, and its size and complexity have historically made it difficult to study in high levels of detail in a modeling environment. In order to understand how this system might be impacted by high penetrations (30% of total annual generation) of wind and solar photovoltaic (PV) during steady state operations, the National Renewable Energy Laboratory (NREL) and the U.S. Department of Energy (DOE) conducted the Eastern Renewable Generation Integration Study (ERGIS). This study investigates certain aspects of the reliability and economic efficiency problem faced by power system operators and planners. Specifically, the study models the ability to meet electricity demand at a 5-minute time interval by scheduling resources for known ramping events, while maintaining adequate reserves to meet random variation in supply and demand, and contingency events. To measure the ability to meet these requirements, a unit commitment and economic dispatch (UC&ED) model is employed to simulate power system operations. The economic costs of managing this system are presented using production costs, a traditional UC&ED metric that does not include any consideration of long-term fixed costs. ERGIS simulated one year of power system operations to understand regional and sub-hourly impacts of wind and PV by developing a comprehensive UC&ED model of the EI. In the analysis, it is shown that, under the study assumptions, generation from approximately 400 GW of combined wind and PV capacity can be balanced on the transmission system at a 5-minute level. In order to address the significant computational burdens associated with a model of this detail we apply novel computing techniques to dramatically reduce simulation solve time while simultaneously increasing the resolution and fidelity of the analysis. Our results also indicate that high penetrations of wind and PV (collectively variable generation (VG

  8. Universal randomness

    Energy Technology Data Exchange (ETDEWEB)

    Dotsenko, Viktor S [Landau Institute for Theoretical Physics, Russian Academy of Sciences, Moscow (Russian Federation)

    2011-03-31

    In the last two decades, it has been established that a single universal probability distribution function, known as the Tracy-Widom (TW) distribution, in many cases provides a macroscopic-level description of the statistical properties of microscopically different systems, including both purely mathematical ones, such as increasing subsequences in random permutations, and quite physical ones, such as directed polymers in random media or polynuclear crystal growth. In the first part of this review, we use a number of models to examine this phenomenon at a simple qualitative level and then consider the exact solution for one-dimensional directed polymers in a random environment, showing that free energy fluctuations in such a system are described by the universal TW distribution. The second part provides detailed appendix material containing the necessary mathematical background for the first part. (reviews of topical problems)

  9. Instant Generation

    Science.gov (United States)

    Loveland, Elaina

    2017-01-01

    Generation Z students (born between 1995-2010) have replaced millennials on college campuses. Generation Z students are entrepreneurial, desire practical skills with their education, and are concerned about the cost of college. This article presents what need to be known about this new generation of students.

  10. True Randomness from Big Data

    Science.gov (United States)

    Papakonstantinou, Periklis A.; Woodruff, David P.; Yang, Guang

    2016-09-01

    Generating random bits is a difficult task, which is important for physical systems simulation, cryptography, and many applications that rely on high-quality random bits. Our contribution is to show how to generate provably random bits from uncertain events whose outcomes are routinely recorded in the form of massive data sets. These include scientific data sets, such as in astronomics, genomics, as well as data produced by individuals, such as internet search logs, sensor networks, and social network feeds. We view the generation of such data as the sampling process from a big source, which is a random variable of size at least a few gigabytes. Our view initiates the study of big sources in the randomness extraction literature. Previous approaches for big sources rely on statistical assumptions about the samples. We introduce a general method that provably extracts almost-uniform random bits from big sources and extensively validate it empirically on real data sets. The experimental findings indicate that our method is efficient enough to handle large enough sources, while previous extractor constructions are not efficient enough to be practical. Quality-wise, our method at least matches quantum randomness expanders and classical world empirical extractors as measured by standardized tests.

  11. Random triangles

    OpenAIRE

    Matula, Dominik

    2013-01-01

    The author summarizes some previous results concerning random triangles. He describes the Gaussian triangle and random triangles whose vertices lie in a unit n-dimensional ball, in a rectangle or in a general bounded convex set. In the second part, the author deals with an inscribed triangle in a triangle - let ABC be an equilateral triangle and let M, N, O be three points, each laying on one side of the ABC. We call MNO inscribed triangle (in an equi- laterral triangle). The median triangle ...

  12. Random matrices

    CERN Document Server

    Mehta, Madan Lal

    1990-01-01

    Since the publication of Random Matrices (Academic Press, 1967) so many new results have emerged both in theory and in applications, that this edition is almost completely revised to reflect the developments. For example, the theory of matrices with quaternion elements was developed to compute certain multiple integrals, and the inverse scattering theory was used to derive asymptotic results. The discovery of Selberg's 1944 paper on a multiple integral also gave rise to hundreds of recent publications. This book presents a coherent and detailed analytical treatment of random matrices, leading

  13. Biotic patterns of heart rate variation in depressed and psychotic subjects.

    Science.gov (United States)

    Sabelli, H; Messer, J; Kovacevic, L; Walthall, K

    2011-01-01

    This article presents novel quantitative methods to study R to R interval (RRI) series that identify their characteristic pattern of organization, Bios, and their variation in psychiatric illness. In this study twenty-four hour series of RRI were extracted from Holter recordings of healthy subjects (N = 74) and small groups of patients with affective depression or psychosis. These data were analyzed with recurrence and statistical methods. In all subjects, RRI series showed complexes (clusters of recurrences), such as those observed with mathematically-generated biotic series but not in chaotic or random series. RRI series from healthy persons showed diversification (increase in variance with the duration of the series analyzed), novelty (less recurrence isometry than copies randomized by shuffling), causal order (more consecutive isometry than shuffled copies), and asymmetric statistical distribution. These imprints of creative processes are characteristic of mathematical Bios, and are absent in chaos. Bios can be distinguished from random walk series by the nonrandom pattern of the series of differences between heartbeats, as well as by measures of consecutive isometry and of partial autocorrelation. These defining characteristics of Bios are significant signs of health. In comparison with healthy controls, psychiatric patient groups showed more isometry and more consecutive isometry than healthy subjects. Psychiatric patients also showed no diversification. This study highlights the process that produces heart rate variation as being non-stationary and creative (bios, not equilibrium or chaos) and causal (not stochastically generated by the coexistence of multiple factors). These results thus are significant regarding psychiatric health.

  14. Assessing randomness and complexity in human motion trajectories through analysis of symbolic sequences

    Directory of Open Access Journals (Sweden)

    Zhen ePeng

    2014-03-01

    Full Text Available Complexity is a hallmark of intelligent behavior consisting both of regular patterns and random variation. To quantitatively assess the complexity and randomness of human motion, we designed a motor task in which we translated subjects' motion trajectories into strings of symbol sequences. In the first part of the experiment participants were asked to perform self-paced movements to create repetitive patterns, copy pre-specified letter sequences, and generate random movements. To investigate whether the degree of randomness can be manipulated, in the second part of the experiment participants were asked to perform unpredictable movements in the context of a pursuit game, where they received feedback from an online Bayesian predictor guessing their next move. We analyzed symbol sequences representing subjects' motion trajectories with five common complexity measures: predictability, compressibility, approximate entropy, Lempel-Ziv complexity, as well as effective measure complexity. We found that subjects’ self-created patterns were the most complex, followed by drawing movements of letters and self-paced random motion. We also found that participants could change the randomness of their behavior depending on context and feedback. Our results suggest that humans can adjust both complexity and regularity in different movement types and contexts and that this can be assessed with information-theoretic measures of the symbolic sequences generated from movement trajectories.

  15. The design of cluster randomized crossover trials

    NARCIS (Netherlands)

    Rietbergen, C.; Moerbeek, M.

    2011-01-01

    The inefficiency induced by between-cluster variation in cluster randomized (CR) trials can be reduced by implementing a crossover (CO) design. In a simple CO trial, each subject receives each treatment in random order. A powerful characteristic of this design is that each subject serves as its own

  16. Electricity generation from biogas

    Energy Technology Data Exchange (ETDEWEB)

    Isensee, E.; Wenzlaff, R.

    1982-01-01

    A biogas plant produces energy throughout the year. This results in high gas surplus in summer. For this reason, the high demand in winter-time cannot be covered as a rule. This incongruity cannot be removed by storage since storage will compensate but short-term supply variations or is to cover short-term peak loads. In addition, electricity generation allows whole-year utilization of the plant.

  17. δ18O and δD variations in some volcanic lakes on the Cameroon Volcanic Line (West-Africa: generating isotopic baseline data for volcano monitoring and surveillance in Cameroon

    Directory of Open Access Journals (Sweden)

    . Issa

    2014-06-01

    Full Text Available Based on geo-anthropological and geochemical studies, catastrophes similar to the unprecedented gas explosions in the mid-1980s from the Cameroonian killer lakes Nyos and Monoun, might occur in any of the 37 other lakes located along the Cameroon Volcanic Line (CVL. Because people could suffer loss and desolation from predictable catastrophes in the future, monitoring/surveillance policies must be established. Due to their location, crater lakes integrate the geochemical processes that develop in the Earth’s crust due to magmatic activities. Therefore, monitoring the surface manifestations of those deep seated and/or hydrothermal processes might reveal increases/decreases in magmatic activities. The anomalous changes in a volcanic lake induced by mixing with exogenous fluids that have a specific δ18O and δD compositional fingerprint (magmatic, metamorphic, etc. could be utilized to predict volcanic hazards. If the steady state of a lake environment and the external and intrinsic parameters that control its hydrodynamics are clearly identified and reasonably understood, the anomalous evolutionary processes that compromise its stability can be identified. This study attempts to collect the δ18O and δD data from 17 Cameroonian lakes to help establish a volcano-related monitoring/surveillance network. This work identifies the processes that control the isotopic composition of the lakes and assesses the intra-/inter- and spatial δ18O/δD variations. Almost all of the lakes contain meteoric water. These lakes are mostly isotopically stratified; epilimnia is generally more positive than the hypolimnia. However, although the rainfall is gradually depleted in heavy isotopes when moving from the South to the North due to the latitude effect, the lakes become more enriched (0.6‰/100 km due to evaporation. The evaluated impact of several parameters on the isotopic variation suggests that the hydrological setting may play an important, albeit not

  18. The Use of Continuous Treatment Versus Placebo or Intermittent Treatment Strategies in Stabilized Patients with Schizophrenia: A Systematic Review and Meta-Analysis of Randomized Controlled Trials with First- and Second-Generation Antipsychotics.

    Science.gov (United States)

    De Hert, Marc; Sermon, Jan; Geerts, Paul; Vansteelandt, Kristof; Peuskens, Joseph; Detraux, Johan

    2015-08-01

    Although continuous treatment with antipsychotics is still recommended as the gold standard treatment paradigm for all patients with schizophrenia, some clinicians question whether continuous antipsychotic treatment is necessary, or even justified, for every patient with schizophrenia who has been stabilized on antipsychotics. The primary objectives of this systematic review and meta-analysis were (i) to compare relapse/hospitalization risks of stabilized patients with schizophrenia under active versus intermittent or placebo treatment conditions; (ii) to examine the role of several study characteristics, possibly intervening in the relationship between relapse risk and treatment condition; and (iii) to examine whether time to relapse is associated with antipsychotic treatment duration. A systematic literature search, using the MEDLINE database (1950 until November 2014), was conducted for English-language published randomized controlled trials, covering a follow-up time period of at least 6 months, and investigating relapse/rehospitalization and/or time-to-relapse rates with placebo or intermittent treatment strategies versus continuous treatment with oral and long-acting injectable first- or second-generation antipsychotics (FGAs/SGAs) in stabilized patients with schizophrenia. Additional studies were identified through searches of reference lists of other identified systematic reviews and Cochrane reports. Two meta-analyses (placebo versus continuous and intermittent versus continuous treatment) were performed to obtain an optimal estimation of the relapse/hospitalization risks of stabilized patients with schizophrenia under these treatment conditions and to assess the role of study characteristics. For time-to-relapse data, a descriptive analysis was performed. Forty-eight reports were selected as potentially eligible for our meta-analysis. Of these, 21 met the inclusion criteria. Twenty-five records, identified through Cochrane and other systematic reviews and

  19. Choice Probability Generating Functions

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; McFadden, Daniel L; Bierlaire, Michel

    This paper considers discrete choice, with choice probabilities coming from maximization of preferences from a random utility field perturbed by additive location shifters (ARUM). Any ARUM can be characterized by a choice-probability generating function (CPGF) whose gradient gives the choice...... probabilities, and every CPGF is consistent with an ARUM. We relate CPGF to multivariate extreme value distributions, and review and extend methods for constructing CPGF for applications....

  20. A Variational Approach to the Modeling of MIMO Systems

    Directory of Open Access Journals (Sweden)

    Jraifi A

    2007-01-01

    Full Text Available Motivated by the study of the optimization of the quality of service for multiple input multiple output (MIMO systems in 3G (third generation, we develop a method for modeling MIMO channel . This method, which uses a statistical approach, is based on a variational form of the usual channel equation. The proposed equation is given by with scalar variable . Minimum distance of received vectors is used as the random variable to model MIMO channel. This variable is of crucial importance for the performance of the transmission system as it captures the degree of interference between neighbors vectors. Then, we use this approach to compute numerically the total probability of errors with respect to signal-to-noise ratio (SNR and then predict the numbers of antennas. By fixing SNR variable to a specific value, we extract informations on the optimal numbers of MIMO antennas.

  1. Epidemic Spreading in Random Rectangular Networks

    CERN Document Server

    Estrada, Ernesto; Moreno, Yamir

    2015-01-01

    Recently, Estrada and Sheerin (Phys. Rev. E 91, 042805 (2015)) developed the random rectangular graph (RRG) model to account for the spatial distribution of nodes in a network allowing the variation of the shape of the unit square commonly used in random geometric graphs (RGGs). Here, we consider an epidemics dynamics taking place on the nodes and edges of an RRG and we derive analytically a lower bound for the epidemic threshold for a Susceptible-Infected-Susceptible (SIS) or Susceptible-Infected-Recovered (SIR) model on these networks. Using extensive numerical simulations of the SIS dynamics we show that the lower bound found is very tight. We conclude that the elongation of the area in which the nodes are distributed makes the network more resilient to the propagation of an epidemics due to the fact that the epidemic threshold increases with the elongation of the rectangle. On the other hand, using the "classical" RGG for modeling epidemics on non-squared cities generates a larger error due to the effects...

  2. Systematic variations in divergence angle

    CERN Document Server

    Okabe, Takuya

    2012-01-01

    Practical methods for quantitative analysis of radial and angular coordinates of leafy organs of vascular plants are presented and applied to published phyllotactic patterns of various real systems from young leaves on a shoot tip to florets on a flower head. The constancy of divergence angle is borne out with accuracy of less than a degree. It is shown that apparent fluctuations in divergence angle are in large part systematic variations caused by the invalid assumption of a fixed center and/or by secondary deformations, while random fluctuations are of minor importance.

  3. Distributed generation

    Energy Technology Data Exchange (ETDEWEB)

    Ness, E.

    1999-09-02

    Distributed generation, locating electricity generators close to the point of consumption, provides some unique benefits to power companies and customers that are not available from centralized electricity generation. Photovoltaic (PV) technology is well suited to distributed applications and can, especially in concert with other distributed resources, provide a very close match to the customer demand for electricity, at a significantly lower cost than the alternatives. In addition to augmenting power from central-station generating plants, incorporating PV systems enables electric utilities to optimize the utilization of existing transmission and distribution.

  4. Genetic variation and population structure in Oryza ...

    Indian Academy of Sciences (India)

    Unknown

    [Thomas G., Sreejayan, Joseph L. and Kuriachan P. 2001 Genetic variation and population structure in Oryza malampuzhaensis. Krish. et .... (Promega). Southern hybridization was carried out as reported earlier (Thomas et al. 2000). Results. DNA fingerprinting. A total of 33 decamer primers randomly selected from C,.

  5. Handling large variations in mechanics: Some applications

    Indian Academy of Sciences (India)

    MS received 11 October 2014; revised 17 February 2015; accepted 1 March 2015. Abstract. There is a need to use probability distributions with power-law decaying tails to describe the large variations exhibited by some of the physical phenomena. The Weierstrass Random Walk (WRW) shows promise for modeling such ...

  6. Virtual standardized patients: an interactive method to examine variation in depression care among primary care physicians

    Science.gov (United States)

    Hooper, Lisa M.; Weinfurt, Kevin P.; Cooper, Lisa A.; Mensh, Julie; Harless, William; Kuhajda, Melissa C.; Epstein, Steven A.

    2009-01-01

    Background Some primary care physicians provide less than optimal care for depression (Kessler et al., Journal of the American Medical Association 291, 2581–90, 2004). However, the literature is not unanimous on the best method to use in order to investigate this variation in care. To capture variations in physician behaviour and decision making in primary care settings, 32 interactive CD-ROM vignettes were constructed and tested. Aim and method The primary aim of this methods-focused paper was to review the extent to which our study method – an interactive CD-ROM patient vignette methodology – was effective in capturing variation in physician behaviour. Specifically, we examined the following questions: (a) Did the interactive CD-ROM technology work? (b) Did we create believable virtual patients? (c) Did the research protocol enable interviews (data collection) to be completed as planned? (d) To what extent was the targeted study sample size achieved? and (e) Did the study interview protocol generate valid and reliable quantitative data and rich, credible qualitative data? Findings Among a sample of 404 randomly selected primary care physicians, our voice-activated interactive methodology appeared to be effective. Specifically, our methodology – combining interactive virtual patient vignette technology, experimental design, and expansive open-ended interview protocol – generated valid explanations for variations in primary care physician practice patterns related to depression care. PMID:20463864

  7. Random walks in a random environment

    Indian Academy of Sciences (India)

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

    Abstract. Random walks as well as diffusions in random media are considered. Methods are developed that allow one to establish large deviation results for both the 'quenched' and the 'averaged' case. Keywords. Large deviations; random walks in a random environment. 1. Introduction. A random walk on Zd is a stochastic ...

  8. Variations in the Perceptions of Peer and Coach Motivational Climate

    Science.gov (United States)

    Vazou, Spiridoula

    2010-01-01

    This study examined (a) variations in the perceptions of peer- and coach-generated motivational climate within and between teams and (b) individual- and group-level factors that can account for these variations. Participants were 483 athletes between 12 and 16 years old. The results showed that perceptions of both peer- and coach-generated climate…

  9. Bilateral renal artery variation

    OpenAIRE

    Üçerler, Hülya; Üzüm, Yusuf; İkiz, Z. Aslı Aktan

    2015-01-01

    Each kidney is supplied by a single renal artery, although renal artery variations are common. Variations of the renal arteryhave become important with the increasing number of renal transplantations. Numerous studies describe variations in renalartery anatomy. Especially the left renal artery is among the most critical arterial variations, because it is the referred side forresecting the donor kidney. During routine dissection in a formalin fixed male cadaver, we have found a bilateral renal...

  10. Studying Variation in Tunes

    NARCIS (Netherlands)

    Janssen, B.; van Kranenburg, P.

    2014-01-01

    Variation in music can be caused by different phenomena: conscious, creative manipulation of musical ideas; but also unconscious variation during music recall. It is the latter phenomenon that we wish to study: variation which occurs in oral transmission, in which a melody is taught without the help

  11. Population and allelic variation of A-to-I RNA editing in human transcriptomes.

    Science.gov (United States)

    Park, Eddie; Guo, Jiguang; Shen, Shihao; Demirdjian, Levon; Wu, Ying Nian; Lin, Lan; Xing, Yi

    2017-07-28

    A-to-I RNA editing is an important step in RNA processing in which specific adenosines in some RNA molecules are post-transcriptionally modified to inosines. RNA editing has emerged as a widespread mechanism for generating transcriptome diversity. However, there remain significant knowledge gaps about the variation and function of RNA editing. In order to determine the influence of genetic variation on A-to-I RNA editing, we integrate genomic and transcriptomic data from 445 human lymphoblastoid cell lines by combining an RNA editing QTL (edQTL) analysis with an allele-specific RNA editing (ASED) analysis. We identify 1054 RNA editing events associated with cis genetic polymorphisms. Additionally, we find that a subset of these polymorphisms is linked to genome-wide association study signals of complex traits or diseases. Finally, compared to random cis polymorphisms, polymorphisms associated with RNA editing variation are located closer spatially to their respective editing sites and have a more pronounced impact on RNA secondary structure. Our study reveals widespread cis variation in RNA editing among genetically distinct individuals and sheds light on possible phenotypic consequences of such variation on complex traits and diseases.

  12. Random tensors

    CERN Document Server

    Gurau, Razvan

    2017-01-01

    Written by the creator of the modern theory of random tensors, this book is the first self-contained introductory text to this rapidly developing theory. Starting from notions familiar to the average researcher or PhD student in mathematical or theoretical physics, the book presents in detail the theory and its applications to physics. The recent detections of the Higgs boson at the LHC and gravitational waves at LIGO mark new milestones in Physics confirming long standing predictions of Quantum Field Theory and General Relativity. These two experimental results only reinforce today the need to find an underlying common framework of the two: the elusive theory of Quantum Gravity. Over the past thirty years, several alternatives have been proposed as theories of Quantum Gravity, chief among them String Theory. While these theories are yet to be tested experimentally, key lessons have already been learned. Whatever the theory of Quantum Gravity may be, it must incorporate random geometry in one form or another....

  13. Random functions and turbulence

    CERN Document Server

    Panchev, S

    1971-01-01

    International Series of Monographs in Natural Philosophy, Volume 32: Random Functions and Turbulence focuses on the use of random functions as mathematical methods. The manuscript first offers information on the elements of the theory of random functions. Topics include determination of statistical moments by characteristic functions; functional transformations of random variables; multidimensional random variables with spherical symmetry; and random variables and distribution functions. The book then discusses random processes and random fields, including stationarity and ergodicity of random

  14. Hydrogen Generator

    Science.gov (United States)

    1983-01-01

    A unit for producing hydrogen on site is used by a New Jersey Electric Company. The hydrogen is used as a coolant for the station's large generator; on-site production eliminates the need for weekly hydrogen deliveries. High purity hydrogen is generated by water electrolysis. The electrolyte is solid plastic and the control system is electronic. The technology was originally developed for the Gemini spacecraft.

  15. Evidence from phylogenetic and genome fingerprinting analyses suggests rapidly changing variation in Halorubrum and Haloarcula populations

    Directory of Open Access Journals (Sweden)

    Nikhil eRam Mohan

    2014-04-01

    Full Text Available Halobacteria require high NaCl concentrations for growth and are the dominant inhabitants of hypersaline environments above 15% NaCl. They are well documented to be highly recombinogenic, both in frequency and in the range of exchange partners. In this study, we examine the genetic and genomic variation of cultured, naturally co-occurring environmental populations of Halobacteria. Sequence data from multiple loci (~2500bp identified closely related strains belonging to the genera Halorubrum and Haloarcula. Genome fingerprinting using a random priming PCR amplification method to analyze these isolates revealed diverse banding patterns within and across each of the genera and surprisingly even for isolates that are identical at the nucleotide level for five protein coding sequenced loci. This variance in genome structure even between identical multilocus sequence analysis (MLSA haplotypes suggests that accumulation of variation is rapid, perhaps occurring every generation.

  16. Random numbers certified by Bell's theorem.

    Science.gov (United States)

    Pironio, S; Acín, A; Massar, S; de la Giroday, A Boyer; Matsukevich, D N; Maunz, P; Olmschenk, S; Hayes, D; Luo, L; Manning, T A; Monroe, C

    2010-04-15

    Randomness is a fundamental feature of nature and a valuable resource for applications ranging from cryptography and gambling to numerical simulation of physical and biological systems. Random numbers, however, are difficult to characterize mathematically, and their generation must rely on an unpredictable physical process. Inaccuracies in the theoretical modelling of such processes or failures of the devices, possibly due to adversarial attacks, limit the reliability of random number generators in ways that are difficult to control and detect. Here, inspired by earlier work on non-locality-based and device-independent quantum information processing, we show that the non-local correlations of entangled quantum particles can be used to certify the presence of genuine randomness. It is thereby possible to design a cryptographically secure random number generator that does not require any assumption about the internal working of the device. Such a strong form of randomness generation is impossible classically and possible in quantum systems only if certified by a Bell inequality violation. We carry out a proof-of-concept demonstration of this proposal in a system of two entangled atoms separated by approximately one metre. The observed Bell inequality violation, featuring near perfect detection efficiency, guarantees that 42 new random numbers are generated with 99 per cent confidence. Our results lay the groundwork for future device-independent quantum information experiments and for addressing fundamental issues raised by the intrinsic randomness of quantum theory.

  17. Tailored Random Graph Ensembles

    Science.gov (United States)

    Roberts, E. S.; Annibale, A.; Coolen, A. C. C.

    2013-02-01

    Tailored graph ensembles are a developing bridge between biological networks and statistical mechanics. The aim is to use this concept to generate a suite of rigorous tools that can be used to quantify and compare the topology of cellular signalling networks, such as protein-protein interaction networks and gene regulation networks. We calculate exact and explicit formulae for the leading orders in the system size of the Shannon entropies of random graph ensembles constrained with degree distribution and degree-degree correlation. We also construct an ergodic detailed balance Markov chain with non-trivial acceptance probabilities which converges to a strictly uniform measure and is based on edge swaps that conserve all degrees. The acceptance probabilities can be generalized to define Markov chains that target any alternative desired measure on the space of directed or undirected graphs, in order to generate graphs with more sophisticated topological features.

  18. Coarse Grained Exponential Variational Autoencoders

    KAUST Repository

    Sun, Ke

    2017-02-25

    Variational autoencoders (VAE) often use Gaussian or category distribution to model the inference process. This puts a limit on variational learning because this simplified assumption does not match the true posterior distribution, which is usually much more sophisticated. To break this limitation and apply arbitrary parametric distribution during inference, this paper derives a \\\\emph{semi-continuous} latent representation, which approximates a continuous density up to a prescribed precision, and is much easier to analyze than its continuous counterpart because it is fundamentally discrete. We showcase the proposition by applying polynomial exponential family distributions as the posterior, which are universal probability density function generators. Our experimental results show consistent improvements over commonly used VAE models.

  19. The parabolic Anderson model random walk in random potential

    CERN Document Server

    König, Wolfgang

    2016-01-01

    This is a comprehensive survey on the research on the parabolic Anderson model – the heat equation with random potential or the random walk in random potential – of the years 1990 – 2015. The investigation of this model requires a combination of tools from probability (large deviations, extreme-value theory, e.g.) and analysis (spectral theory for the Laplace operator with potential, variational analysis, e.g.). We explain the background, the applications, the questions and the connections with other models and formulate the most relevant results on the long-time behavior of the solution, like quenched and annealed asymptotics for the total mass, intermittency, confinement and concentration properties and mass flow. Furthermore, we explain the most successful proof methods and give a list of open research problems. Proofs are not detailed, but concisely outlined and commented; the formulations of some theorems are slightly simplified for better comprehension.

  20. Variation Tolerant On-Chip Interconnects

    CERN Document Server

    Nigussie, Ethiopia Enideg

    2012-01-01

    This book presents design techniques, analysis and implementation of high performance and power efficient, variation tolerant on-chip interconnects.  Given the design paradigm shift to multi-core, interconnect-centric designs and the increase in sources of variability and their impact in sub-100nm technologies, this book will be an invaluable reference for anyone concerned with the design of next generation, high-performance electronics systems. Provides comprehensive, circuit-level explanation of high-performance, energy-efficient, variation-tolerant on-chip interconnect; Describes design techniques to mitigate problems caused by variation; Includes techniques for design and implementation of self-timed on-chip interconnect, delay variation insensitive communication protocols, high speed signaling techniques and circuits, bit-width independent completion detection and process, voltage and temperature variation tolerance.                          

  1. Analysis of a global random stratified sample of nurse legislation.

    Science.gov (United States)

    Benton, D C; Fernández-Fernández, M P; González-Jurado, M A; Beneit-Montesinos, J V

    2015-06-01

    To identify, compare and contrast the major component parts of heterogeneous stratified sample of nursing legislation. Nursing legislation varies from one jurisdiction to another. Up until now no research exists into whether the variations of such legislation are random or if variations are related to a set of key attributes. This mixed method study used a random stratified sample of legislation to map through documentary analysis the content of 14 nursing acts and then explored, using quantitative techniques, whether the material contained relates to a number of key attributes. These attributes include: legal tradition of the jurisdiction; model of regulation; administrative approach; area of the world; and the economic status of the jurisdiction. Twelve component parts of nursing legislation were identified. These were remarkably similar irrespective of attributes of interest. However, not all component parts were specified in the same level of detail and the manner by which the elements were addressed did vary. A number of potential relationships between the structure of the legislation and the key attributes of interest were identified. This study generated a comprehensive and integrated map of a global sample of nursing legislation. It provides a set of descriptors to be used to undertake further quantitative work and provides an important policy tool to facilitate dialogue between regulatory bodies. At the individual nurse level it offers insights that can help nurses pursue recognition of credentials across jurisdictions. © 2015 International Council of Nurses.

  2. Frequency regulator for synchronous generators

    Science.gov (United States)

    Karlicek, Robert F.

    1982-01-01

    The present invention is directed to a novel frequency regulator which controls a generator output frequency for variations in both the input power to the generator and the power supplied to an uncontrolled external load. The present invention further includes over current and current balance protection devices which are relatively inexpensive to manufacture, which may be encapsulated to provide protection from the operating environment and which respond more quickly than previously known electromechanical devices.

  3. [Research progress of molecular genetic analysis in Schistosoma variation].

    Science.gov (United States)

    Zheng, Su-Yue; Li, Fei

    2014-02-01

    The development of molecular biology techniques makes important contributions to the researches of heritable variation of Schistosoma. In recent years, the molecular genetic analysis in the Schistosoma variation researches mainly includes the restriction fragment length polymorphism (RFLP), random amplified polymorphism technology (RAPD), microsatellite anchored PCR (SSR-PCR), and polymerase reaction single-strand conformation polymorphism (PCR-SSCP). This article reviews the research progress of molecular genetic analysis in Schistosoma variation in recent years.

  4. Next-generation phylogenomics

    Directory of Open Access Journals (Sweden)

    Chan Cheong Xin

    2013-01-01

    Full Text Available Abstract Thanks to advances in next-generation technologies, genome sequences are now being generated at breadth (e.g. across environments and depth (thousands of closely related strains, individuals or samples unimaginable only a few years ago. Phylogenomics – the study of evolutionary relationships based on comparative analysis of genome-scale data – has so far been developed as industrial-scale molecular phylogenetics, proceeding in the two classical steps: multiple alignment of homologous sequences, followed by inference of a tree (or multiple trees. However, the algorithms typically employed for these steps scale poorly with number of sequences, such that for an increasing number of problems, high-quality phylogenomic analysis is (or soon will be computationally infeasible. Moreover, next-generation data are often incomplete and error-prone, and analysis may be further complicated by genome rearrangement, gene fusion and deletion, lateral genetic transfer, and transcript variation. Here we argue that next-generation data require next-generation phylogenomics, including so-called alignment-free approaches. Reviewers Reviewed by Mr Alexander Panchin (nominated by Dr Mikhail Gelfand, Dr Eugene Koonin and Prof Peter Gogarten. For the full reviews, please go to the Reviewers’ comments section.

  5. MCNP LWR Core Generator

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Noah A. [Los Alamos National Laboratory

    2012-08-14

    The reactor core input generator allows for MCNP input files to be tailored to design specifications and generated in seconds. Full reactor models can now easily be created by specifying a small set of parameters and generating an MCNP input for a full reactor core. Axial zoning of the core will allow for density variation in the fuel and moderator, with pin-by-pin fidelity, so that BWR cores can more accurately be modeled. LWR core work in progress: (1) Reflectivity option for specifying 1/4, 1/2, or full core simulation; (2) Axial zoning for moderator densities that vary with height; (3) Generating multiple types of assemblies for different fuel enrichments; and (4) Parameters for specifying BWR box walls. Fuel pin work in progress: (1) Radial and azimuthal zoning for generating further unique materials in fuel rods; (2) Options for specifying different types of fuel for MOX or multiple burn assemblies; (3) Additional options for replacing fuel rods with burnable poison rods; and (4) Control rod/blade modeling.

  6. Idea generation

    DEFF Research Database (Denmark)

    Tollestrup, Christian H. T.; Laursen, Linda Nhu

    2015-01-01

    as having new sociocultural meaning in line with Vergantis definition of radical innovation. This paper discusses the results of an experiment with 32 students on idea generation and product concept development. The experiment was setup as and A-B comparison between two set of students with the same...... of an idea generation whether the outset is ill defined and questioned as opposed to straightforward ideation on a proposal for a solution? The hypothesis is that an approach to ideation where ambiguity and discrepancy deliberately is sought creates more radical innovation that an approach without this...

  7. Solar Generator

    Science.gov (United States)

    1985-01-01

    The Vanguard I dish-Stirling module program, initiated in 1982, produced the Vanguard I module, a commercial prototype erected by the Advanco Corporation. The module, which automatically tracks the sun, combines JPL mirrored concentrator technology, an advanced Stirling Solar II engine/generator, a low cost microprocessor-controlled parabolic dish. Vanguard I has a 28% sunlight to electricity conversion efficiency. If tests continue to prove the system effective, Advanco will construct a generating plant to sell electricity to local utilities. An agreement has also been signed with McDonnell Douglas to manufacture a similar module.

  8. Uso de modelos de regressão aleatória para descrever a variação genética da produção de leite na raça Holandesa Random regressions models to describe the genetic variation of milk yield in Holstein breed

    Directory of Open Access Journals (Sweden)

    Cláudio Vieira de Araújo

    2006-06-01

    . The Wilmink's exponential function, the Ali and Schaeffer logarithmic function and the Legendre orthogonal polynomials of second and fourth order were used. The comparisons among the models were based on the following criteria: estimates of variance components of the multiple-trait model and random regressions models, values of residual variance and values of the logarithms of the likelihood functions. The heritability estimates obtained using the multiple-trait model varied from 0.110 to 0.244, for the random regression models the values ranged from 0.127 to 0.301, being the largest estimates observed in the models with larger number of parameters. The random regression models which used the Legendre polynomials was the model which better described the genetic variation of the milk yield.

  9. Analysis of genetic variation in Erianthus arundinaceum by random ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-10-06

    Oct 6, 2008 ... Key words: Erianthus arundinaceum, genetic diversity, RAPD, UPGMA. INTRODUCTION. Saccharum spp. is one ... pro-grams, information on the genetic diversity within and among closely related crop ... accession code was shown in the Table 1, and M is 100 bp DNA ladder. Individual RAPD fragments for ...

  10. Detection of somaclonal variation by random amplified polymorphic ...

    African Journals Online (AJOL)

    Phalaenopsis bellina (Rchb.f.) Christenson orchid species are known for their beautiful flower shape, graceful inflorescence and fragrance. Protocorm-like bodies (PLBs) of P. bellina were induced from leaf segments. The PLBs were then subjected to proliferation using ½ strength Murashige and Skoog (MS) media with two ...

  11. Random walks on reductive groups

    CERN Document Server

    Benoist, Yves

    2016-01-01

    The classical theory of Random Walks describes the asymptotic behavior of sums of independent identically distributed random real variables. This book explains the generalization of this theory to products of independent identically distributed random matrices with real coefficients. Under the assumption that the action of the matrices is semisimple – or, equivalently, that the Zariski closure of the group generated by these matrices is reductive - and under suitable moment assumptions, it is shown that the norm of the products of such random matrices satisfies a number of classical probabilistic laws. This book includes necessary background on the theory of reductive algebraic groups, probability theory and operator theory, thereby providing a modern introduction to the topic.

  12. Quantifying randomness in real networks

    Science.gov (United States)

    Orsini, Chiara; Dankulov, Marija M.; Colomer-de-Simón, Pol; Jamakovic, Almerima; Mahadevan, Priya; Vahdat, Amin; Bassler, Kevin E.; Toroczkai, Zoltán; Boguñá, Marián; Caldarelli, Guido; Fortunato, Santo; Krioukov, Dmitri

    2015-10-01

    Represented as graphs, real networks are intricate combinations of order and disorder. Fixing some of the structural properties of network models to their values observed in real networks, many other properties appear as statistical consequences of these fixed observables, plus randomness in other respects. Here we employ the dk-series, a complete set of basic characteristics of the network structure, to study the statistical dependencies between different network properties. We consider six real networks--the Internet, US airport network, human protein interactions, technosocial web of trust, English word network, and an fMRI map of the human brain--and find that many important local and global structural properties of these networks are closely reproduced by dk-random graphs whose degree distributions, degree correlations and clustering are as in the corresponding real network. We discuss important conceptual, methodological, and practical implications of this evaluation of network randomness, and release software to generate dk-random graphs.

  13. Generative Contexts

    Science.gov (United States)

    Lyles, Dan Allen

    Educational research has identified how science, technology, engineering, and mathematics (STEM) practice and education have underperforming metrics in racial and gender diversity, despite decades of intervention. These disparities are part of the construction of a culture of science that is alienating to these populations. Recent studies in a social science framework described as "Generative Justice" have suggested that the context of social and scientific practice might be modified to bring about more just and equitable relations among the disenfranchised by circulating the value they and their non-human allies create back to them in unalienated forms. What is not known are the underlying principles of social and material space that makes a system more or less generative. I employ an autoethnographic method at four sites: a high school science class; a farm committed to "Black and Brown liberation"; a summer program geared towards youth environmental mapping; and a summer workshop for Harlem middle school students. My findings suggest that by identifying instances where material affinity, participatory voice, and creative solidarity are mutually reinforcing, it is possible to create educational contexts that generate unalienated value, and circulate it back to the producers themselves. This cycle of generation may help explain how to create systems of justice that strengthen and grow themselves through successive iterations. The problem of lack of diversity in STEM may be addressed not merely by recruiting the best and the brightest from underrepresented populations, but by changing the context of STEM education to provide tools for its own systematic restructuring.

  14. Choice probability generating functions

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; McFadden, Daniel; Bierlaire, Michel

    2013-01-01

    This paper considers discrete choice, with choice probabilities coming from maximization of preferences from a random utility field perturbed by additive location shifters (ARUM). Any ARUM can be characterized by a choice-probability generating function (CPGF) whose gradient gives the choice...... probabilities, and every CPGF is consistent with an ARUM. We relate CPGF to multivariate extreme value distributions, and review and extend methods for constructing CPGF for applications. The choice probabilities of any ARUM may be approximated by a cross-nested logit model. The results for ARUM are extended...

  15. Heat Generation During Bony Decompression of Lumbar Spinal Stenosis Using a High-Speed Diamond Drill with or without Automated Irrigation and an Ultrasonic Bone-Cutting Knife: A Single-Blinded Prospective Randomized Controlled Study.

    Science.gov (United States)

    Matthes, Marc; Pillich, Dirk Thomas; El Refaee, Ehab; Schroeder, Henry W S; Müller, Jan-Uwe

    2017-12-08

    The main objective of the present prospective, randomized, single-blinded controlled study was to measure heat during bony decompression of lumbar spinal stenosis with high-speed drills and an ultrasonic bone-cutting knife. Ninety patients diagnosed with lumbar spinal stenosis were included in this study and randomized for lumbar spinal canal decompression using either a high-speed drill with automatic irrigation, high-speed drill with manual irrigation, or an ultrasonic bone-cutting knife with automatic irrigation (USBCD). For evaluation of group homogeneity, a visual analog scale pain score and neurologic findings were measured preoperatively and postoperatively. Temperatures during bony decompression were measured using a forward-looking infrared camera system. Clinical results among the 3 groups did not differ in pain reduction, improvement of neurologic findings, or the rate of complications. However, significantly lower values were found for absolute and mean maximal temperatures during bony decompression in the USBCD group compared with the groups of patients who received the high-speed drill with automatic irrigation and the high-speed drill with manual irrigation, indicating this technique to be less aggressive in terms of thermal induction of bone necrosis. USBCD allows more precise bone removal compared with high-speed drills, and despite increased device time, no significant difference in the overall decompression time was observed. All methods examined produced short temperature peaks with possible, at least temporary, damage to bone and neural tissue. Automatic irrigation was associated with lower heat development compared with manual irrigation. Despite evidence of critical temperatures, no clinical correlation (e.g., neurologic deficits) was encountered in this study. Clinically, all 3 methods presented equally good results. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Random fixed points and random differential inclusions

    Directory of Open Access Journals (Sweden)

    Nikolaos S. Papageorgiou

    1988-01-01

    Full Text Available In this paper, first, we study random best approximations to random sets, using fixed point techniques, obtaining this way stochastic analogues of earlier deterministic results by Browder-Petryshyn, KyFan and Reich. Then we prove two fixed point theorems for random multifunctions with stochastic domain that satisfy certain tangential conditions. Finally we consider a random differential inclusion with upper semicontinuous orientor field and establish the existence of random solutions.

  17. Entropy Characterization of Random Network Models

    Directory of Open Access Journals (Sweden)

    Pedro J. Zufiria

    2017-06-01

    Full Text Available This paper elaborates on the Random Network Model (RNM as a mathematical framework for modelling and analyzing the generation of complex networks. Such framework allows the analysis of the relationship between several network characterizing features (link density, clustering coefficient, degree distribution, connectivity, etc. and entropy-based complexity measures, providing new insight on the generation and characterization of random networks. Some theoretical and computational results illustrate the utility of the proposed framework.

  18. Choice probability generating functions

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; McFadden, Daniel; Bierlaire, Michel

    2010-01-01

    This paper establishes that every random utility discrete choice model (RUM) has a representation that can be characterized by a choice-probability generating function (CPGF) with specific properties, and that every function with these specific properties is consistent with a RUM. The choice...... probabilities from the RUM are obtained from the gradient of the CPGF. Mixtures of RUM are characterized by logarithmic mixtures of their associated CPGF. The paper relates CPGF to multivariate extreme value distributions, and reviews and extends methods for constructing generating functions for applications....... The choice probabilities of any ARUM may be approximated by a cross-nested logit model. The results for ARUM are extended to competing risk survival models....

  19. Copy number variation and mutation

    Science.gov (United States)

    Clark, Brian; Weidner, Jacob; Wabick, Kevin

    2009-11-01

    Until very recently, the standard model of DNA included two genes for each trait. This dated model has given way to a model that includes copies of some genes well in excess of the canonical two. Copy number variations in the human genome play critical roles in causing or aggravating a number of syndromes and diseases while providing increased resistance to others. We explore the role of mutation, crossover, inversion, and reproduction in determining copy number variations in a numerical simulation of a population. The numerical model consists of a population of individuals, where each individual is represented by a single strand of DNA with the same number of genes. Each gene is initially assigned to one of two traits. Fitness of the individual is determined by the two most fit genes for trait one, and trait two genetic material is treated as a reservoir of junk DNA. After a sufficient number of generations, during which the genetic distribution is allowed to reach a steady-state, the mean numberof genes per trait and the copy number variation are recorded. Here, we focus on the role of mutation and compare simulation results to theory.

  20. Composite continuous time random walks

    Science.gov (United States)

    Hilfer, Rudolf

    2017-12-01

    Random walks in composite continuous time are introduced. Composite time flow is the product of translational time flow and fractional time flow [see Chem. Phys. 84, 399 (2002)]. The continuum limit of composite continuous time random walks gives a diffusion equation where the infinitesimal generator of time flow is the sum of a first order and a fractional time derivative. The latter is specified as a generalized Riemann-Liouville derivative. Generalized and binomial Mittag-Leffler functions are found as the exact results for waiting time density and mean square displacement.

  1. How Affiliation Disclosure and Control Over User-Generated Comments Affects Consumer Health Knowledge and Behavior: A Randomized Controlled Experiment of Pharmaceutical Direct-to-Consumer Advertising on Social Media

    Science.gov (United States)

    Vendemia, Megan Ashley

    2016-01-01

    Background More people are seeking health information online than ever before and pharmaceutical companies are increasingly marketing their drugs through social media. Objective The aim was to examine two major concerns related to online direct-to-consumer pharmaceutical advertising: (1) how disclosing an affiliation with a pharmaceutical company affects how people respond to drug information produced by both health organizations and online commenters, and (2) how knowledge that health organizations control the display of user-generated comments affects consumer health knowledge and behavior. Methods We conducted a 2×2×2 between-subjects experiment (N=674). All participants viewed an infographic posted to Facebook by a health organization about a prescription allergy drug. Across conditions, the infographic varied in the degree to which the health organization and commenters appeared to be affiliated with a drug manufacturer, and the display of user-generated comments appeared to be controlled. Results Affiliation disclosure statements on a health organization’s Facebook post increased perceptions of an organization-drug manufacturer connection, which reduced trust in the organization (point estimate –0.45, 95% CI –0.69 to –0.24) and other users who posted comments about the drug (point estimate –0.44, 95% CI –0.68 to –0.22). Furthermore, increased perceptions of an organization-manufacturer connection reduced the likelihood that people would recommend the drug to important others (point estimate –0.35, 95% CI –0.59 to –0.15), and share the drug post with others on Facebook (point estimate –0.37, 95% CI –0.64 to –0.16). An affiliation cue next to the commenters' names increased perceptions that the commenters were affiliated with the drug manufacturer, which reduced trust in the comments (point estimate –0.81, 95% CI –1.04 to –0.59), the organization that made the post (point estimate –0.68, 95% CI –0.90 to –0.49), the

  2. How Affiliation Disclosure and Control Over User-Generated Comments Affects Consumer Health Knowledge and Behavior: A Randomized Controlled Experiment of Pharmaceutical Direct-to-Consumer Advertising on Social Media.

    Science.gov (United States)

    DeAndrea, David Christopher; Vendemia, Megan Ashley

    2016-07-19

    More people are seeking health information online than ever before and pharmaceutical companies are increasingly marketing their drugs through social media. The aim was to examine two major concerns related to online direct-to-consumer pharmaceutical advertising: (1) how disclosing an affiliation with a pharmaceutical company affects how people respond to drug information produced by both health organizations and online commenters, and (2) how knowledge that health organizations control the display of user-generated comments affects consumer health knowledge and behavior. We conducted a 2×2×2 between-subjects experiment (N=674). All participants viewed an infographic posted to Facebook by a health organization about a prescription allergy drug. Across conditions, the infographic varied in the degree to which the health organization and commenters appeared to be affiliated with a drug manufacturer, and the display of user-generated comments appeared to be controlled. Affiliation disclosure statements on a health organization's Facebook post increased perceptions of an organization-drug manufacturer connection, which reduced trust in the organization (point estimate -0.45, 95% CI -0.69 to -0.24) and other users who posted comments about the drug (point estimate -0.44, 95% CI -0.68 to -0.22). Furthermore, increased perceptions of an organization-manufacturer connection reduced the likelihood that people would recommend the drug to important others (point estimate -0.35, 95% CI -0.59 to -0.15), and share the drug post with others on Facebook (point estimate -0.37, 95% CI -0.64 to -0.16). An affiliation cue next to the commenters' names increased perceptions that the commenters were affiliated with the drug manufacturer, which reduced trust in the comments (point estimate -0.81, 95% CI -1.04 to -0.59), the organization that made the post (point estimate -0.68, 95% CI -0.90 to -0.49), the likelihood of participants recommending the drug (point estimate -0.61, 95% CI -0

  3. Magnet Free Generators - 3rd Generation Wind Turbine Generators

    DEFF Research Database (Denmark)

    Jensen, Bogi Bech; Mijatovic, Nenad; Henriksen, Matthew Lee

    2013-01-01

    This paper presents an introduction to superconducting wind turbine generators, which are often referred to as 3rd generation wind turbine generators. Advantages and challenges of superconducting generators are presented with particular focus on possible weight and efficiency improvements. A comp....... A comparison of the rare earth usage in different topologies of permanent magnet generators and superconducting generators is also presented....

  4. Long term outcomes of new generation drug eluting stents versus coronary artery bypass grafting for multivessel and/or left main coronary artery disease. A Bayesian network meta-analysis of randomized controlled trials.

    Science.gov (United States)

    Mina, George S; Watti, Hussam; Soliman, Demiana; Shewale, Anand; Atkins, Jessica; Reddy, Pratap; Dominic, Paari

    2018-01-05

    Most data guiding revascularization of multivessel disease (MVD) and/or left main disease (LMD) favor coronary artery bypass grafting (CABG) over percutaneous coronary intervention (PCI). However, those data are based on trials comparing CABG to bare metal stents (BMS) or old generation drug eluting stents (OG-DES). Hence, it is essential to outcomes of CABG to those of new generation drug eluting stents (NG-DES). We searched PUBMED and Cochrane database for trials evaluating revascularization of MVD and/or LMD with CABG and/or PCI. A Bayesian network meta-analysis was performed to calculate odds ratios (OR) and 95% credible intervals (CrI). Primary outcome was major adverse cardiovascular events (MACE) at 3-5 years. Secondary outcomes were mortality, cerebrovascular accidents (CVA), myocardial infarction (MI) and repeat revascularization. We included 10 trials with a total of 9287 patients. CABG was associated with lower MACE when compared to BMS or OG-DES. However, MACE was not significantly different between CABG and NG-DES (OR 0.79, CrI 0.45-1.40). Moreover, there were no significant differences between CABG and NG-DES in mortality (OR 0.78, CrI 0.45-1.37), CVA (OR 0.93 CrI 0.35-2.2) or MI (OR 0.6, CrI 0.17-2.0). On the other hand, CABG was associated with lower repeat revascularization (OR 0.55, CrI 0.36-0.84). Our study suggests that NG-DES is an acceptable alternative to CABG in patients with MVD and/or LMD. However, repeat revascularization remains to be lower with CABG than with PCI. Copyright © 2018. Published by Elsevier Inc.

  5. Effects of closed-loop stimulation vs. DDD pacing on haemodynamic variations and occurrence of syncope induced by head-up tilt test in older patients with refrac\\tory cardioinhibitory vasovagal syncope: the Tilt test-Induced REsponse in Closed-loop Stimulation multicentre, prospective, single blind, randomized study.

    Science.gov (United States)

    Palmisano, Pietro; Dell'Era, Gabriele; Russo, Vincenzo; Zaccaria, Maria; Mangia, Rolando; Bortnik, Miriam; De Vecchi, Federica; Giubertoni, Ailia; Patti, Fabiana; Magnani, Andrea; Nigro, Gerardo; Rago, Anna; Occhetta, Eraldo; Accogli, Michele

    2017-04-12

    Closed-loop stimulation (CLS) seemed promising in preventing the recurrence of vasovagal syncope (VVS) in patients with a cardioinhibitory response to head-up tilt test (HUTT) compared with conventional pacing. We hypothesized that the better results of this algorithm are due to its quick reaction in high-rate pacing delivered in the early phase of vasovagal reflex, which increase the cardiac output and the blood pressure preventing loss of consciousness. This prospective, randomized, single-blind, multicentre study was designed as an intra-patient comparison and enrolled 30 patients (age 62.2 ± 13.5 years, males 60.0%) with cardioinhibitory VVS, carrying a dual-chamber pacemaker incorporating CLS algorithm. Two HUTTs were performed one week apart: one during DDD-CLS 60-130/min pacing and the other during DDD 60/min pacing; patients were randomly and blindly assigned to two groups: in one the first HUTT was performed in DDD-CLS (n = 15), in the other in DDD (n = 15). Occurrence of syncope and haemodynamic variations induced by HUTT was recorded during the tests. Compared with DDD, DDD-CLS significantly reduced the occurrence of syncope induced by HUTT (30.0% vs. 76.7%; P DDD and DDD-CLS mode, DDD-CLS significantly delayed the onset of syncope during HUTT (from 20.8 ± 3.9 to 24.8 ± 0.9 min; P = 0.032). The maximum fall in systolic blood pressure recorded during HUTT was significantly lower in DDD-CLS compared with DDD (43.2 ± 30.3 vs. 65.1 ± 25.8 mmHg; P = 0.004). In patients with cardioinhibitory VVS, CLS reduces the occurrence of syncope induced by HUTT, compared with DDD pacing. When CLS is not able to abort the vasovagal reflex, it seems to delay the onset of syncope.

  6. Keystream Generator Based On Simulated Annealing

    Directory of Open Access Journals (Sweden)

    Ayad A. Abdulsalam

    2011-01-01

    Full Text Available Advances in the design of keystream generator using heuristic techniques are reported. A simulated annealing algorithm for generating random keystream with large complexity is presented. Simulated annealing technique is adapted to locate these requirements. The definitions for some cryptographic properties are generalized, providing a measure suitable for use as an objective function in a simulated annealing algorithm, seeking randomness that satisfy both correlation immunity and the large linear complexity. Results are presented demonstrating the effectiveness of the method.

  7. Solar generator

    Energy Technology Data Exchange (ETDEWEB)

    Barkats, G.; Chenin, C.; Foucras, J.; Marnay, L.

    1978-07-18

    The present invention relates to a solar generator for producing electrical energy from solar energy, mounted in particular on board an artificial satellite and constituted by a plurality of pivoted panels, stacked but unfoldable, each of which comprises a thick frame inside which is disposed a thin flexible support carrying solar cells, said frame comprising intermediate stiffeners connecting two opposite sides of the frame, wherein each panel comprises, between two intermediate stiffeners and between the end intermediate stiffeners and the sides of the frame there-opposite, a plurality of wide, flat auxiliary stiffeners, transverse with respect to the intermediate stiffeners and on which said flexible support is fixed at least partially.

  8. Ensembl variation resources

    Directory of Open Access Journals (Sweden)

    Marin-Garcia Pablo

    2010-05-01

    Full Text Available Abstract Background The maturing field of genomics is rapidly increasing the number of sequenced genomes and producing more information from those previously sequenced. Much of this additional information is variation data derived from sampling multiple individuals of a given species with the goal of discovering new variants and characterising the population frequencies of the variants that are already known. These data have immense value for many studies, including those designed to understand evolution and connect genotype to phenotype. Maximising the utility of the data requires that it be stored in an accessible manner that facilitates the integration of variation data with other genome resources such as gene annotation and comparative genomics. Description The Ensembl project provides comprehensive and integrated variation resources for a wide variety of chordate genomes. This paper provides a detailed description of the sources of data and the methods for creating the Ensembl variation databases. It also explores the utility of the information by explaining the range of query options available, from using interactive web displays, to online data mining tools and connecting directly to the data servers programmatically. It gives a good overview of the variation resources and future plans for expanding the variation data within Ensembl. Conclusions Variation data is an important key to understanding the functional and phenotypic differences between individuals. The development of new sequencing and genotyping technologies is greatly increasing the amount of variation data known for almost all genomes. The Ensembl variation resources are integrated into the Ensembl genome browser and provide a comprehensive way to access this data in the context of a widely used genome bioinformatics system. All Ensembl data is freely available at http://www.ensembl.org and from the public MySQL database server at ensembldb.ensembl.org.

  9. True randomness from an incoherent source

    Science.gov (United States)

    Qi, Bing

    2017-11-01

    Quantum random number generators (QRNGs) harness the intrinsic randomness in measurement processes: the measurement outputs are truly random, given the input state is a superposition of the eigenstates of the measurement operators. In the case of trusted devices, true randomness could be generated from a mixed state ρ so long as the system entangled with ρ is well protected. We propose a random number generation scheme based on measuring the quadrature fluctuations of a single mode thermal state using an optical homodyne detector. By mixing the output of a broadband amplified spontaneous emission (ASE) source with a single mode local oscillator (LO) at a beam splitter and performing differential photo-detection, we can selectively detect the quadrature fluctuation of a single mode output of the ASE source, thanks to the filtering function of the LO. Experimentally, a quadrature variance about three orders of magnitude larger than the vacuum noise has been observed, suggesting this scheme can tolerate much higher detector noise in comparison with QRNGs based on measuring the vacuum noise. The high quality of this entropy source is evidenced by the small correlation coefficients of the acquired data. A Toeplitz-hashing extractor is applied to generate unbiased random bits from the Gaussian distributed raw data, achieving an efficiency of 5.12 bits per sample. The output of the Toeplitz extractor successfully passes all the NIST statistical tests for random numbers.

  10. Variational Transition State Theory

    Energy Technology Data Exchange (ETDEWEB)

    Truhlar, Donald G. [Univ. of Minnesota, Minneapolis, MN (United States)

    2016-09-29

    This is the final report on a project involving the development and applications of variational transition state theory. This project involved the development of variational transition state theory for gas-phase reactions, including optimized multidimensional tunneling contributions and the application of this theory to gas-phase reactions with a special emphasis on developing reaction rate theory in directions that are important for applications to combustion. The development of variational transition state theory with optimized multidimensional tunneling as a useful computational tool for combustion kinetics involved eight objectives.

  11. Optimal codon randomization via mathematical programming.

    Science.gov (United States)

    Nov, Yuval; Segev, Danny

    2013-10-21

    Codon randomization via degenerate oligonucleotides is a widely used approach for generating protein libraries. We use integer programming methodology to model and solve the problem of computing the minimal mixture of oligonucleotides required to induce an arbitrary target probability over the 20 standard amino acids. We consider both randomization via conventional degenerate oligonucleotides, which incorporate at each position of the randomized codon certain nucleotides in equal probabilities, and randomization via spiked oligonucleotides, which admit arbitrary nucleotide distribution at each of the codon's positions. Existing methods for computing such mixtures rely on various heuristics. © 2013 Elsevier Ltd. All rights reserved.

  12. QUASI-RANDOM TESTING OF COMPUTER SYSTEMS

    Directory of Open Access Journals (Sweden)

    S. V. Yarmolik

    2013-01-01

    Full Text Available Various modified random testing approaches have been proposed for computer system testing in the black box environment. Their effectiveness has been evaluated on the typical failure patterns by employing three measures, namely, P-measure, E-measure and F-measure. A quasi-random testing, being a modified version of the random testing, has been proposed and analyzed. The quasi-random Sobol sequences and modified Sobol sequences are used as the test patterns. Some new methods for Sobol sequence generation have been proposed and analyzed.

  13. Characterisation of random DFB Raman laser amplifier for WDM transmission

    National Research Council Canada - National Science Library

    Rosa, Paweł; Rizzelli, Giuseppe; Tan, Mingming; Harper, Paul; Ania-Castañόn, Juan Diego

    2015-01-01

    We perform a full numerical characterisation of half-open cavity random DFB Raman fibre laser amplifier schemes for WDM transmission in terms of signal power variation, noise and nonlinear impairments...

  14. Modeling Gene Regulation in Liver Hepatocellular Carcinoma with Random Forests

    National Research Council Canada - National Science Library

    Hilal Kazan

    2016-01-01

    .... We developed a random forest model that incorporates copy-number variation, DNA methylation, transcription factor, and microRNA binding information as features to predict gene expression in HCC...

  15. Saturn chorus latitudinal variations

    National Research Council Canada - National Science Library

    Menietti, J. D; Hospodarsky, G. B; Shprits, Y. Y; Gurnett, D. A

    2014-01-01

    The variation of propagation properties of whistler mode chorus as a function of latitude is not well known at Saturn but is important for the calculation of pitch angle diffusion and nonlinear growth of chorus...

  16. Variation within categories.

    NARCIS (Netherlands)

    Das-Smaal, E.A.; Swart, de J.H.

    1984-01-01

    Two aspects of variation within categories, relating to different models of categorization, were investigated - frequency of dimensional values and typicality differences within values. The influence of range of typicality experienced during learning and of informational value of feedback was also

  17. Variational principles in physics

    CERN Document Server

    Basdevant, Jean-Louis

    2007-01-01

    Optimization under constraints is an essential part of everyday life. Indeed, we routinely solve problems by striking a balance between contradictory interests, individual desires and material contingencies. This notion of equilibrium was dear to thinkers of the enlightenment, as illustrated by Montesquieu’s famous formulation: "In all magistracies, the greatness of the power must be compensated by the brevity of the duration." Astonishingly, natural laws are guided by a similar principle. Variational principles have proven to be surprisingly fertile. For example, Fermat used variational methods to demonstrate that light follows the fastest route from one point to another, an idea which came to be known as Fermat’s principle, a cornerstone of geometrical optics. Variational Principles in Physics explains variational principles and charts their use throughout modern physics. The heart of the book is devoted to the analytical mechanics of Lagrange and Hamilton, the basic tools of any physicist. Prof. Basdev...

  18. Generalized quasi variational inequalities

    Energy Technology Data Exchange (ETDEWEB)

    Noor, M.A. [King Saud Univ., Riyadh (Saudi Arabia)

    1996-12-31

    In this paper, we establish the equivalence between the generalized quasi variational inequalities and the generalized implicit Wiener-Hopf equations using essentially the projection technique. This equivalence is used to suggest and analyze a number of new iterative algorithms for solving generalized quasi variational inequalities and the related complementarity problems. The convergence criteria is also considered. The results proved in this paper represent a significant improvement and refinement of the previously known results.

  19. Germanic Verb Particle Variation

    DEFF Research Database (Denmark)

    Vikner, Sten

    2017-01-01

    This paper has two closely related goals. The more "global" one is to present an overview of the variation conceming verb particles across the Germanic languages (see e.g. den Dikken 1995; Haiden 2005; Mclntyre 2007 and many others), and the more "local" one is to use some of this variation data ...... to argue for Yiddish being an SOV-language like German and Dutch rather than an SVO-language like English and the Scandinavian languages....

  20. Enhancing superconducting critical current by randomness

    Science.gov (United States)

    Wang, Y. L.; Thoutam, L. R.; Xiao, Z. L.; Shen, B.; Pearson, J. E.; Divan, R.; Ocola, L. E.; Crabtree, G. W.; Kwok, W. K.

    2016-01-01

    The key ingredient of high critical currents in a type-II superconductor is defect sites that pin vortices. Contrary to earlier understanding on nanopatterned artificial pinning, here we show unequivocally the advantages of a random pinscape over an ordered array in a wide magnetic field range. We reveal that the better performance of a random pinscape is due to the variation of its local density of pinning sites (LDOPS), which mitigates the motion of vortices. This is confirmed by achieving even higher enhancement of the critical current through a conformally mapped random pinscape, where the distribution of the LDOPS is further enlarged. The demonstrated key role of LDOPS in enhancing superconducting critical currents gets at the heart of random versus commensurate pinning. Our findings highlight the importance of random pinscapes in enhancing the superconducting critical currents of applied superconductors.