WorldWideScience

Sample records for time step restrictions

  1. Stepping Stones through Time

    Directory of Open Access Journals (Sweden)

    Emily Lyle

    2012-03-01

    Full Text Available Indo-European mythology is known only through written records but it needs to be understood in terms of the preliterate oral-cultural context in which it was rooted. It is proposed that this world was conceptually organized through a memory-capsule consisting of the current generation and the three before it, and that there was a system of alternate generations with each generation taking a step into the future under the leadership of a white or red king.

  2. Time step MOTA thermostat simulation

    International Nuclear Information System (INIS)

    Guthrie, G.L.

    1978-09-01

    The report details the logic, program layout, and operating procedures for the time-step MOTA (Materials Open Test Assembly) thermostat simulation program known as GYRD. It will enable prospective users to understand the operation of the program, run it, and interpret the results. The time-step simulation analysis was the approach chosen to determine the maximum value gain that could be used to minimize steady temperature offset without risking undamped thermal oscillations. The advantage of the GYRD program is that it directly shows hunting, ringing phenomenon, and similar events. Programs BITT and CYLB are faster, but do not directly show ringing time

  3. Grief: Difficult Times, Simple Steps.

    Science.gov (United States)

    Waszak, Emily Lane

    This guide presents techniques to assist others in coping with the loss of a loved one. Using the language of 9 layperson, the book contains more than 100 tips for caregivers or loved ones. A simple step is presented on each page, followed by reasons and instructions for each step. Chapters include: "What to Say"; "Helpful Things to Do"; "Dealing…

  4. Symplectic integrators with adaptive time steps

    Science.gov (United States)

    Richardson, A. S.; Finn, J. M.

    2012-01-01

    In recent decades, there have been many attempts to construct symplectic integrators with variable time steps, with rather disappointing results. In this paper, we identify the causes for this lack of performance, and find that they fall into two categories. In the first, the time step is considered a function of time alone, Δ = Δ(t). In this case, backward error analysis shows that while the algorithms remain symplectic, parametric instabilities may arise because of resonance between oscillations of Δ(t) and the orbital motion. In the second category the time step is a function of phase space variables Δ = Δ(q, p). In this case, the system of equations to be solved is analyzed by introducing a new time variable τ with dt = Δ(q, p) dτ. The transformed equations are no longer in Hamiltonian form, and thus do not benefit from integration methods which would be symplectic for Hamiltonian systems. We analyze two methods for integrating the transformed equations which do, however, preserve the structure of the original equations. The first is an extended phase space method, which has been successfully used in previous studies of adaptive time step symplectic integrators. The second, novel, method is based on a non-canonical mixed-variable generating function. Numerical trials for both of these methods show good results, without parametric instabilities or spurious growth or damping. It is then shown how to adapt the time step to an error estimate found by backward error analysis, in order to optimize the time-stepping scheme. Numerical results are obtained using this formulation and compared with other time-stepping schemes for the extended phase space symplectic method.

  5. Time to pause before the next step

    International Nuclear Information System (INIS)

    Siemon, R.E.

    1998-01-01

    Many scientists, who have staunchly supported ITER for years, are coming to realize it is time to further rethink fusion energy's development strategy. Specifically, as was suggested by Grant Logan and Dale Meade, and in keeping with the restructuring of 1996, a theme of better, cheaper, faster fusion would serve the program more effectively than ''demonstrating controlled ignition...and integrated testing of the high-heat-flux and nuclear components required to utilize fusion energy...'' which are the important ingredients of ITER's objectives. The author has personally shifted his view for a mixture of technical and political reasons. On the technical side, he senses that through advanced tokamak research, spherical tokamak research, and advanced stellarator work, scientists are coming to a new understanding that might make a burning-plasma device significantly smaller and less expensive. Thus waiting for a few years, even ten years, seems prudent. Scientifically, there is fascinating physics to be learned through studies of burning plasma on a tokamak. And clearly if one wishes to study burning plasma physics in a sustained plasma, there is no other configuration with an adequate database on which to proceed. But what is the urgency of moving towards an ITER-like step focused on burning plasma? Some of the arguments put forward and the counter arguments are discussed here

  6. Time step length versus efficiency of Monte Carlo burnup calculations

    International Nuclear Information System (INIS)

    Dufek, Jan; Valtavirta, Ville

    2014-01-01

    Highlights: • Time step length largely affects efficiency of MC burnup calculations. • Efficiency of MC burnup calculations improves with decreasing time step length. • Results were obtained from SIE-based Monte Carlo burnup calculations. - Abstract: We demonstrate that efficiency of Monte Carlo burnup calculations can be largely affected by the selected time step length. This study employs the stochastic implicit Euler based coupling scheme for Monte Carlo burnup calculations that performs a number of inner iteration steps within each time step. In a series of calculations, we vary the time step length and the number of inner iteration steps; the results suggest that Monte Carlo burnup calculations get more efficient as the time step length is reduced. More time steps must be simulated as they get shorter; however, this is more than compensated by the decrease in computing cost per time step needed for achieving a certain accuracy

  7. Fasting, circadian rhythms, and time restricted feeding in healthy lifespan

    OpenAIRE

    Longo, Valter D.; Panda, Satchidananda

    2016-01-01

    Feeding in most animals is confined to a defined period, leaving short periods of fasting that coincide with sleep. Fasting enables organisms to enter alternative metabolic phases, which rely less on glucose and more on ketone body-like carbon sources. Both intermittent and periodic fasting result in benefits ranging from prevention to the enhanced treatment of diseases. Similarly, time-restricted feeding (TRF), in which feeding time is restricted to certain hours of the day, allows the daily...

  8. High-resolution seismic wave propagation using local time stepping

    KAUST Repository

    Peter, Daniel

    2017-03-13

    High-resolution seismic wave simulations often require local refinements in numerical meshes to accurately capture e.g. steep topography or complex fault geometry. Together with explicit time schemes, this dramatically reduces the global time step size for ground-motion simulations due to numerical stability conditions. To alleviate this problem, local time stepping (LTS) algorithms allow an explicit time stepping scheme to adapt the time step to the element size, allowing nearoptimal time steps everywhere in the mesh. This can potentially lead to significantly faster simulation runtimes.

  9. Diffeomorphic image registration with automatic time-step adjustment

    DEFF Research Database (Denmark)

    Pai, Akshay Sadananda Uppinakudru; Klein, S.; Sommer, Stefan Horst

    2015-01-01

    In this paper, we propose an automated Euler's time-step adjustment scheme for diffeomorphic image registration using stationary velocity fields (SVFs). The proposed variational problem aims at bounding the inverse consistency error by adaptively adjusting the number of Euler's step required to r...... accuracy as a fixed time-step scheme however at a much less computational cost....

  10. An explicit multi-time-stepping algorithm for aerodynamic flows

    OpenAIRE

    Niemann-Tuitman, B.E.; Veldman, A.E.P.

    1997-01-01

    An explicit multi-time-stepping algorithm with applications to aerodynamic flows is presented. In the algorithm, in different parts of the computational domain different time steps are taken, and the flow is synchronized at the so-called synchronization levels. The algorithm is validated for aerodynamic turbulent flows. For two-dimensional flows speedups in the order of five with respect to single time stepping are obtained.

  11. Combating cancer one step at a time

    Directory of Open Access Journals (Sweden)

    R.N Sugitha Nadarajah

    2016-10-01

    widespread consequences, not only in a medical sense but also socially and economically,” says Dr. Abdel-Rahman. “We need to put in every effort to combat this fatal disease,” he adds.Tackling the spread of cancer and the increase in the number of cases reported every year is not without its challenges, he asserts. “I see the key challenges as the unequal availability of cancer treatments worldwide, the increasing cost of cancer treatment, and the increased median age of the population in many parts of the world, which carries with it a consequent increase in the risk of certain cancers,” he says. “We need to reassess the current pace and orientation of cancer research because, with time, cancer research is becoming industry-oriented rather than academia-oriented — which, in my view, could be very dangerous to the future of cancer research,” adds Dr. Abdel-Rahman. “Governments need to provide more research funding to improve the outcome of cancer patients,” he explains.His efforts and hard work have led to him receiving a number of distinguished awards, namely the UICC International Cancer Technology Transfer (ICRETT fellowship in 2014 at the Investigational New Drugs Unit in the European Institute of Oncology, Milan, Italy; EACR travel fellowship in 2015 at The Christie NHS Foundation Trust, Manchester, UK; and also several travel grants to Ireland, Switzerland, Belgium, Spain, and many other countries where he attended medical conferences. Dr. Abdel-Rahman is currently engaged in a project to establish a clinical/translational cancer research center at his institute, which seeks to incorporate various cancer-related disciplines in order to produce a real bench-to-bedside practice, hoping that it would “change research that may help shape the future of cancer therapy”.Dr. Abdel-Rahman is also an active founding member of the clinical research unit at his institute and is a representative to the prestigious European Organization for Research and

  12. An explicit multi-time-stepping algorithm for aerodynamic flows

    NARCIS (Netherlands)

    Niemann-Tuitman, B.E.; Veldman, A.E.P.

    1997-01-01

    An explicit multi-time-stepping algorithm with applications to aerodynamic flows is presented. In the algorithm, in different parts of the computational domain different time steps are taken, and the flow is synchronized at the so-called synchronization levels. The algorithm is validated for

  13. High-resolution seismic wave propagation using local time stepping

    KAUST Repository

    Peter, Daniel; Rietmann, Max; Galvez, Percy; Ampuero, Jean Paul

    2017-01-01

    High-resolution seismic wave simulations often require local refinements in numerical meshes to accurately capture e.g. steep topography or complex fault geometry. Together with explicit time schemes, this dramatically reduces the global time step

  14. Time step size selection for radiation diffusion calculations

    International Nuclear Information System (INIS)

    Rider, W.J.; Knoll, D.A.

    1999-01-01

    The purpose of this note is to describe a time step control technique as applied to radiation diffusion. Standard practice only provides a heuristic criteria related to the relative change in the dependent variables. The authors propose an alternative based on relatively simple physical principles. This time step control applies to methods of solution that are unconditionally stable and converges nonlinearities within a time step in the governing equations. Commonly, nonlinearities in the governing equations are evaluated using existing (old time) data. The authors refer to this as the semi-implicit (SI) method. When a method converges nonlinearities within a time step, the entire governing equation including all nonlinearities is self-consistently evaluated using advance time data (with appropriate time centering for accuracy)

  15. Fasting, circadian rhythms, and time restricted feeding in healthy lifespan

    Science.gov (United States)

    Longo, Valter D.; Panda, Satchidananda

    2016-01-01

    Summary Feeding in most animals is confined to a defined period, leaving short periods of fasting that coincide with sleep. Fasting enables organisms to enter alternative metabolic phases, which rely less on glucose and more on ketone body-like carbon sources. Both intermittent and periodic fasting result in benefits ranging from prevention to the enhanced treatment of diseases. Similarly, time-restricted feeding (TRF), in which feeding time is restricted to certain hours of the day, allows the daily fasting period to last >12 h, thus imparting pleiotropic benefits in multiple organisms. Understanding the mechanistic link between nutrients and the fasting benefits is leading to the identification of fasting mimicking diets (FMDs) that achieve changes similar to those caused by fasting. Given the pleiotropic and sustained benefits of TRF and FMD, both basic science and translational research are warranted to develop fasting-associated interventions into effective and inexpensive treatments with the potential to improve healthspan. PMID:27304506

  16. Stability analysis and time-step limits for a Monte Carlo Compton-scattering method

    International Nuclear Information System (INIS)

    Densmore, Jeffery D.; Warsa, James S.; Lowrie, Robert B.

    2010-01-01

    A Monte Carlo method for simulating Compton scattering in high energy density applications has been presented that models the photon-electron collision kinematics exactly [E. Canfield, W.M. Howard, E.P. Liang, Inverse Comptonization by one-dimensional relativistic electrons, Astrophys. J. 323 (1987) 565]. However, implementing this technique typically requires an explicit evaluation of the material temperature, which can lead to unstable and oscillatory solutions. In this paper, we perform a stability analysis of this Monte Carlo method and develop two time-step limits that avoid undesirable behavior. The first time-step limit prevents instabilities, while the second, more restrictive time-step limit avoids both instabilities and nonphysical oscillations. With a set of numerical examples, we demonstrate the efficacy of these time-step limits.

  17. Newmark local time stepping on high-performance computing architectures

    KAUST Repository

    Rietmann, Max

    2016-11-25

    In multi-scale complex media, finite element meshes often require areas of local refinement, creating small elements that can dramatically reduce the global time-step for wave-propagation problems due to the CFL condition. Local time stepping (LTS) algorithms allow an explicit time-stepping scheme to adapt the time-step to the element size, allowing near-optimal time-steps everywhere in the mesh. We develop an efficient multilevel LTS-Newmark scheme and implement it in a widely used continuous finite element seismic wave-propagation package. In particular, we extend the standard LTS formulation with adaptations to continuous finite element methods that can be implemented very efficiently with very strong element-size contrasts (more than 100×). Capable of running on large CPU and GPU clusters, we present both synthetic validation examples and large scale, realistic application examples to demonstrate the performance and applicability of the method and implementation on thousands of CPU cores and hundreds of GPUs.

  18. Newmark local time stepping on high-performance computing architectures

    Energy Technology Data Exchange (ETDEWEB)

    Rietmann, Max, E-mail: max.rietmann@erdw.ethz.ch [Institute for Computational Science, Università della Svizzera italiana, Lugano (Switzerland); Institute of Geophysics, ETH Zurich (Switzerland); Grote, Marcus, E-mail: marcus.grote@unibas.ch [Department of Mathematics and Computer Science, University of Basel (Switzerland); Peter, Daniel, E-mail: daniel.peter@kaust.edu.sa [Institute for Computational Science, Università della Svizzera italiana, Lugano (Switzerland); Institute of Geophysics, ETH Zurich (Switzerland); Schenk, Olaf, E-mail: olaf.schenk@usi.ch [Institute for Computational Science, Università della Svizzera italiana, Lugano (Switzerland)

    2017-04-01

    In multi-scale complex media, finite element meshes often require areas of local refinement, creating small elements that can dramatically reduce the global time-step for wave-propagation problems due to the CFL condition. Local time stepping (LTS) algorithms allow an explicit time-stepping scheme to adapt the time-step to the element size, allowing near-optimal time-steps everywhere in the mesh. We develop an efficient multilevel LTS-Newmark scheme and implement it in a widely used continuous finite element seismic wave-propagation package. In particular, we extend the standard LTS formulation with adaptations to continuous finite element methods that can be implemented very efficiently with very strong element-size contrasts (more than 100x). Capable of running on large CPU and GPU clusters, we present both synthetic validation examples and large scale, realistic application examples to demonstrate the performance and applicability of the method and implementation on thousands of CPU cores and hundreds of GPUs.

  19. Newmark local time stepping on high-performance computing architectures

    KAUST Repository

    Rietmann, Max; Grote, Marcus; Peter, Daniel; Schenk, Olaf

    2016-01-01

    In multi-scale complex media, finite element meshes often require areas of local refinement, creating small elements that can dramatically reduce the global time-step for wave-propagation problems due to the CFL condition. Local time stepping (LTS) algorithms allow an explicit time-stepping scheme to adapt the time-step to the element size, allowing near-optimal time-steps everywhere in the mesh. We develop an efficient multilevel LTS-Newmark scheme and implement it in a widely used continuous finite element seismic wave-propagation package. In particular, we extend the standard LTS formulation with adaptations to continuous finite element methods that can be implemented very efficiently with very strong element-size contrasts (more than 100×). Capable of running on large CPU and GPU clusters, we present both synthetic validation examples and large scale, realistic application examples to demonstrate the performance and applicability of the method and implementation on thousands of CPU cores and hundreds of GPUs.

  20. Time-dependent restricted-active-space self-consistent-field theory for laser-driven many-electron dynamics

    DEFF Research Database (Denmark)

    Miyagi, Haruhide; Madsen, Lars Bojer

    2013-01-01

    We present the time-dependent restricted-active-space self-consistent-field (TD-RASSCF) theory as a framework for the time-dependent many-electron problem. The theory generalizes the multiconfigurational time-dependent Hartree-Fock (MCTDHF) theory by incorporating the restricted-active-space scheme...... well known in time-independent quantum chemistry. Optimization of the orbitals as well as the expansion coefficients at each time step makes it possible to construct the wave function accurately while using only a relatively small number of electronic configurations. In numerical calculations of high...

  1. Two-step digit-set-restricted modified signed-digit addition-subtraction algorithm and its optoelectronic implementation.

    Science.gov (United States)

    Qian, F; Li, G; Ruan, H; Jing, H; Liu, L

    1999-09-10

    A novel, to our knowledge, two-step digit-set-restricted modified signed-digit (MSD) addition-subtraction algorithm is proposed. With the introduction of the reference digits, the operand words are mapped into an intermediate carry word with all digits restricted to the set {1, 0} and an intermediate sum word with all digits restricted to the set {0, 1}, which can be summed to form the final result without carry generation. The operation can be performed in parallel by use of binary logic. An optical system that utilizes an electron-trapping device is suggested for accomplishing the required binary logic operations. By programming of the illumination of data arrays, any complex logic operations of multiple variables can be realized without additional temporal latency of the intermediate results. This technique has a high space-bandwidth product and signal-to-noise ratio. The main structure can be stacked to construct a compact optoelectronic MSD adder-subtracter.

  2. Multi-time-step domain coupling method with energy control

    DEFF Research Database (Denmark)

    Mahjoubi, N.; Krenk, Steen

    2010-01-01

    the individual time step. It is demonstrated that displacement continuity between the subdomains leads to cancelation of the interface contributions to the energy balance equation, and thus stability and algorithmic damping properties of the original algorithms are retained. The various subdomains can...... by a numerical example using a refined mesh around concentrated forces. Copyright © 2010 John Wiley & Sons, Ltd....

  3. Sharing Steps in the Workplace: Changing Privacy Concerns Over Time

    DEFF Research Database (Denmark)

    Jensen, Nanna Gorm; Shklovski, Irina

    2016-01-01

    study of a Danish workplace participating in a step counting campaign. We find that concerns of employees who choose to participate and those who choose not to differ. Moreover, privacy concerns of participants develop and change over time. Our findings challenge the assumption that consumers...

  4. Studies on steps affecting tritium residence time in solid blanket

    International Nuclear Information System (INIS)

    Tanaka, Satoru

    1987-01-01

    For the self sustaining of CTR fuel cycle, the effective tritium recovery from blankets is essential. This means that not only tritium breeding ratio must be larger than 1.0, but also high recovering speed is required for the short residence time of tritium in blankets. Short residence time means that the tritium inventory in blankets is small. In this paper, the tritium residence time and tritium inventory in a solid blanket are modeled by considering the steps constituting tritium release. Some of these tritium migration processes were experimentally evaluated. The tritium migration steps in a solid blanket using sintered breeding materials consist of diffusion in grains, desorption at grain edges, diffusion and permeation through grain boundaries, desorption at particle edges, diffusion and percolation through interconnected pores to purging stream, and convective mass transfer to stream. Corresponding to these steps, diffusive, soluble, adsorbed and trapped tritium inventories and the tritium in gas phase are conceivable. The code named TTT was made for calculating these tritium inventories and the residence time of tritium. An example of the results of calculation is shown. The blanket is REPUTER-1, which is the conceptual design of a commercial reversed field pinch fusion reactor studied at the University of Tokyo. The experimental studies on the migration steps of tritium are reported. (Kako, I.)

  5. Considerations for the independent reaction times and step-by-step methods for radiation chemistry simulations

    Science.gov (United States)

    Plante, Ianik; Devroye, Luc

    2017-10-01

    Ionizing radiation interacts with the water molecules of the tissues mostly by ionizations and excitations, which result in the formation of the radiation track structure and the creation of radiolytic species such as H.,.OH, H2, H2O2, and e-aq. After their creation, these species diffuse and may chemically react with the neighboring species and with the molecules of the medium. Therefore radiation chemistry is of great importance in radiation biology. As the chemical species are not distributed homogeneously, the use of conventional models of homogeneous reactions cannot completely describe the reaction kinetics of the particles. Actually, many simulations of radiation chemistry are done using the Independent Reaction Time (IRT) method, which is a very fast technique to calculate radiochemical yields but which do not calculate the positions of the radiolytic species as a function of time. Step-by-step (SBS) methods, which are able to provide such information, have been used only sparsely because these are time-consuming in terms of calculation. Recent improvements in computer performance now allow the regular use of the SBS method in radiation chemistry. The SBS and IRT methods are both based on the Green's functions of the diffusion equation (GFDE). In this paper, several sampling algorithms of the GFDE and for the IRT method are presented. We show that the IRT and SBS methods are exactly equivalent for 2-particles systems for diffusion and partially diffusion-controlled reactions between non-interacting particles. We also show that the results obtained with the SBS simulation method with periodic boundary conditions are in agreement with the predictions by classical reaction kinetics theory, which is an important step towards using this method for modelling of biochemical networks and metabolic pathways involved in oxidative stress. Finally, the first simulation results obtained with the code RITRACKS (Relativistic Ion Tracks) are presented.

  6. A parallel nearly implicit time-stepping scheme

    OpenAIRE

    Botchev, Mike A.; van der Vorst, Henk A.

    2001-01-01

    Across-the-space parallelism still remains the most mature, convenient and natural way to parallelize large scale problems. One of the major problems here is that implicit time stepping is often difficult to parallelize due to the structure of the system. Approximate implicit schemes have been suggested to circumvent the problem. These schemes have attractive stability properties and they are also very well parallelizable. The purpose of this article is to give an overall assessment of the pa...

  7. Adaptive time-stepping Monte Carlo integration of Coulomb collisions

    Science.gov (United States)

    Särkimäki, K.; Hirvijoki, E.; Terävä, J.

    2018-01-01

    We report an accessible and robust tool for evaluating the effects of Coulomb collisions on a test particle in a plasma that obeys Maxwell-Jüttner statistics. The implementation is based on the Beliaev-Budker collision integral which allows both the test particle and the background plasma to be relativistic. The integration method supports adaptive time stepping, which is shown to greatly improve the computational efficiency. The Monte Carlo method is implemented for both the three-dimensional particle momentum space and the five-dimensional guiding center phase space. Detailed description is provided for both the physics and implementation of the operator. The focus is in adaptive integration of stochastic differential equations, which is an overlooked aspect among existing Monte Carlo implementations of Coulomb collision operators. We verify that our operator converges to known analytical results and demonstrate that careless implementation of the adaptive time step can lead to severely erroneous results. The operator is provided as a self-contained Fortran 95 module and can be included into existing orbit-following tools that trace either the full Larmor motion or the guiding center dynamics. The adaptive time-stepping algorithm is expected to be useful in situations where the collision frequencies vary greatly over the course of a simulation. Examples include the slowing-down of fusion products or other fast ions, and the Dreicer generation of runaway electrons as well as the generation of fast ions or electrons with ion or electron cyclotron resonance heating.

  8. Multiple time step integrators in ab initio molecular dynamics

    International Nuclear Information System (INIS)

    Luehr, Nathan; Martínez, Todd J.; Markland, Thomas E.

    2014-01-01

    Multiple time-scale algorithms exploit the natural separation of time-scales in chemical systems to greatly accelerate the efficiency of molecular dynamics simulations. Although the utility of these methods in systems where the interactions are described by empirical potentials is now well established, their application to ab initio molecular dynamics calculations has been limited by difficulties associated with splitting the ab initio potential into fast and slowly varying components. Here we present two schemes that enable efficient time-scale separation in ab initio calculations: one based on fragment decomposition and the other on range separation of the Coulomb operator in the electronic Hamiltonian. We demonstrate for both water clusters and a solvated hydroxide ion that multiple time-scale molecular dynamics allows for outer time steps of 2.5 fs, which are as large as those obtained when such schemes are applied to empirical potentials, while still allowing for bonds to be broken and reformed throughout the dynamics. This permits computational speedups of up to 4.4x, compared to standard Born-Oppenheimer ab initio molecular dynamics with a 0.5 fs time step, while maintaining the same energy conservation and accuracy

  9. [Collaborative application of BEPS at different time steps.

    Science.gov (United States)

    Lu, Wei; Fan, Wen Yi; Tian, Tian

    2016-09-01

    BEPSHourly is committed to simulate the ecological and physiological process of vegetation at hourly time steps, and is often applied to analyze the diurnal change of gross primary productivity (GPP), net primary productivity (NPP) at site scale because of its more complex model structure and time-consuming solving process. However, daily photosynthetic rate calculation in BEPSDaily model is simpler and less time-consuming, not involving many iterative processes. It is suitable for simulating the regional primary productivity and analyzing the spatial distribution of regional carbon sources and sinks. According to the characteristics and applicability of BEPSDaily and BEPSHourly models, this paper proposed a method of collaborative application of BEPS at daily and hourly time steps. Firstly, BEPSHourly was used to optimize the main photosynthetic parameters: the maximum rate of carboxylation (V c max ) and the maximum rate of photosynthetic electron transport (J max ) at site scale, and then the two optimized parameters were introduced into BEPSDaily model to estimate regional NPP at regional scale. The results showed that optimization of the main photosynthesis parameters based on the flux data could improve the simulate ability of the model. The primary productivity of different forest types in descending order was deciduous broad-leaved forest, mixed forest, coniferous forest in 2011. The collaborative application of carbon cycle models at different steps proposed in this study could effectively optimize the main photosynthesis parameters V c max and J max , simulate the monthly averaged diurnal GPP, NPP, calculate the regional NPP, and analyze the spatial distribution of regional carbon sources and sinks.

  10. Time step size limitation introduced by the BSSN Gamma Driver

    Energy Technology Data Exchange (ETDEWEB)

    Schnetter, Erik, E-mail: schnetter@cct.lsu.ed [Department of Physics and Astronomy, Louisiana State University, LA (United States)

    2010-08-21

    Many mesh refinement simulations currently performed in numerical relativity counteract instabilities near the outer boundary of the simulation domain either by changes to the mesh refinement scheme or by changes to the gauge condition. We point out that the BSSN Gamma Driver gauge condition introduces a time step size limitation in a similar manner as a Courant-Friedrichs-Lewy condition, but which is independent of the spatial resolution. We give a didactic explanation of this issue, show why, especially, mesh refinement simulations suffer from it, and point to a simple remedy. (note)

  11. Human keratinocytes restrict chikungunya virus replication at a post-fusion step

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, Eric [Centre d' étude d’agents Pathogènes et Biotechnologies pour la Santé, CPBS CNRS- UMR5236/UM1/UM2, Montpellier (France); Hamel, Rodolphe [Laboratoire Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution, Contrôle, UMR 5290 CNRS/IRD/UM1, Montpellier (France); Neyret, Aymeric [Centre d' étude d’agents Pathogènes et Biotechnologies pour la Santé, CPBS CNRS- UMR5236/UM1/UM2, Montpellier (France); Ekchariyawat, Peeraya [Laboratoire Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution, Contrôle, UMR 5290 CNRS/IRD/UM1, Montpellier (France); Molès, Jean-Pierre [INSERM U1058, UM1, CHU Montpellier (France); Simmons, Graham [Blood Systems Research Institute, San Francisco, CA 94118 (United States); Chazal, Nathalie [Centre d' étude d’agents Pathogènes et Biotechnologies pour la Santé, CPBS CNRS- UMR5236/UM1/UM2, Montpellier (France); Desprès, Philippe [Unité Interactions Moléculaires Flavivirus-Hôtes, Institut Pasteur, Paris (France); and others

    2015-02-15

    Transmission of chikungunya virus (CHIKV) to humans is initiated by puncture of the skin by a blood-feeding Aedes mosquito. Despite the growing knowledge accumulated on CHIKV, the interplay between skin cells and CHIKV following inoculation still remains unclear. In this study we questioned the behavior of human keratinocytes, the predominant cell population in the skin, following viral challenge. We report that CHIKV rapidly elicits an innate immune response in these cells leading to the enhanced transcription of type I/II and type III interferon genes. Concomitantly, we show that despite viral particles internalization into Rab5-positive endosomes and efficient fusion of virus and cell membranes, keratinocytes poorly replicate CHIKV as attested by absence of nonstructural proteins and genomic RNA synthesis. Accordingly, human keratinocytes behave as an antiviral defense against CHIKV infection rather than as a primary targets for initial replication. This picture significantly differs from that reported for Dengue and West Nile mosquito-borne viruses. - Highlights: • Human keratinocytes support endocytosis of CHIKV and fusion of viral membranes. • CHIKV replication is blocked at a post entry step in these cells. • Infection upregulates type-I, –II and –III IFN genes expression. • Keratinocytes behave as immune sentinels against CHIKV.

  12. Human keratinocytes restrict chikungunya virus replication at a post-fusion step

    International Nuclear Information System (INIS)

    Bernard, Eric; Hamel, Rodolphe; Neyret, Aymeric; Ekchariyawat, Peeraya; Molès, Jean-Pierre; Simmons, Graham; Chazal, Nathalie; Desprès, Philippe

    2015-01-01

    Transmission of chikungunya virus (CHIKV) to humans is initiated by puncture of the skin by a blood-feeding Aedes mosquito. Despite the growing knowledge accumulated on CHIKV, the interplay between skin cells and CHIKV following inoculation still remains unclear. In this study we questioned the behavior of human keratinocytes, the predominant cell population in the skin, following viral challenge. We report that CHIKV rapidly elicits an innate immune response in these cells leading to the enhanced transcription of type I/II and type III interferon genes. Concomitantly, we show that despite viral particles internalization into Rab5-positive endosomes and efficient fusion of virus and cell membranes, keratinocytes poorly replicate CHIKV as attested by absence of nonstructural proteins and genomic RNA synthesis. Accordingly, human keratinocytes behave as an antiviral defense against CHIKV infection rather than as a primary targets for initial replication. This picture significantly differs from that reported for Dengue and West Nile mosquito-borne viruses. - Highlights: • Human keratinocytes support endocytosis of CHIKV and fusion of viral membranes. • CHIKV replication is blocked at a post entry step in these cells. • Infection upregulates type-I, –II and –III IFN genes expression. • Keratinocytes behave as immune sentinels against CHIKV

  13. Positivity-preserving dual time stepping schemes for gas dynamics

    Science.gov (United States)

    Parent, Bernard

    2018-05-01

    A new approach at discretizing the temporal derivative of the Euler equations is here presented which can be used with dual time stepping. The temporal discretization stencil is derived along the lines of the Cauchy-Kowalevski procedure resulting in cross differences in spacetime but with some novel modifications which ensure the positivity of the discretization coefficients. It is then shown that the so-obtained spacetime cross differences result in changes to the wave speeds and can thus be incorporated within Roe or Steger-Warming schemes (with and without reconstruction-evolution) simply by altering the eigenvalues. The proposed approach is advantaged over alternatives in that it is positivity-preserving for the Euler equations. Further, it yields monotone solutions near discontinuities while exhibiting a truncation error in smooth regions less than the one of the second- or third-order accurate backward-difference-formula (BDF) for either small or large time steps. The high resolution and positivity preservation of the proposed discretization stencils are independent of the convergence acceleration technique which can be set to multigrid, preconditioning, Jacobian-free Newton-Krylov, block-implicit, etc. Thus, the current paper also offers the first implicit integration of the time-accurate Euler equations that is positivity-preserving in the strict sense (that is, the density and temperature are guaranteed to remain positive). This is in contrast to all previous positivity-preserving implicit methods which only guaranteed the positivity of the density, not of the temperature or pressure. Several stringent reacting and inert test cases confirm the positivity-preserving property of the proposed method as well as its higher resolution and higher computational efficiency over other second-order and third-order implicit temporal discretization strategies.

  14. The importance of time-stepping errors in ocean models

    Science.gov (United States)

    Williams, P. D.

    2011-12-01

    Many ocean models use leapfrog time stepping. The Robert-Asselin (RA) filter is usually applied after each leapfrog step, to control the computational mode. However, it will be shown in this presentation that the RA filter generates very large amounts of numerical diapycnal mixing. In some ocean models, the numerical diapycnal mixing from the RA filter is as large as the physical diapycnal mixing. This lowers our confidence in the fidelity of the simulations. In addition to the above problem, the RA filter also damps the physical solution and degrades the numerical accuracy. These two concomitant problems occur because the RA filter does not conserve the mean state, averaged over the three time slices on which it operates. The presenter has recently proposed a simple modification to the RA filter, which does conserve the three-time-level mean state. The modified filter has become known as the Robert-Asselin-Williams (RAW) filter. When used in conjunction with the leapfrog scheme, the RAW filter eliminates the numerical damping of the physical solution and increases the amplitude accuracy by two orders, yielding third-order accuracy. The phase accuracy is unaffected and remains second-order. The RAW filter can easily be incorporated into existing models of the ocean, typically via the insertion of just a single line of code. Better simulations are obtained, at almost no additional computational expense. Results will be shown from recent implementations of the RAW filter in various ocean models. For example, in the UK Met Office Hadley Centre ocean model, sea-surface temperature and sea-ice biases in the North Atlantic Ocean are found to be reduced. These improvements are encouraging for the use of the RAW filter in other ocean models.

  15. Dwell time modulation restrictions do not necessarily improve treatment plan quality for prostate HDR brachytherapy

    International Nuclear Information System (INIS)

    Balvert, Marleen; Gorissen, Bram L; Den Hertog, Dick; Hoffmann, Aswin L

    2015-01-01

    Inverse planning algorithms for dwell time optimisation in interstitial high-dose-rate (HDR) brachytherapy may produce solutions with large dwell time variations within catheters, which may result in undesirable selective high-dose subvolumes. Extending the dwell time optimisation model with a dwell time modulation restriction (DTMR) that limits dwell time differences between neighboring dwell positions has been suggested to eliminate this problem. DTMRs may additionally reduce the sensitivity for uncertainties in dwell positions that inevitably result from catheter reconstruction errors and afterloader source positioning inaccuracies. This study quantifies the reduction of high-dose subvolumes and the robustness against these uncertainties by applying a DTMR to template-based prostate HDR brachytherapy implants. Three different DTMRs were consecutively applied to a linear dose-based penalty model (LD) and a dose-volume based model (LDV), both obtained from literature. The models were solved with DTMR levels ranging from no restriction to uniform dwell times within catheters in discrete steps. Uncertainties were simulated on clinical cases using in-house developed software, and dose-volume metrics were calculated in each simulation. For the assessment of high-dose subvolumes, the dose homogeneity index (DHI) and the contiguous dose volume histogram were analysed. Robustness was measured by the improvement of the lowest D 90% of the planning target volume (PTV) observed in the simulations. For (LD), a DTMR yields an increase in DHI of approximately 30% and reduces the size of the largest high-dose volume by 2–5 cc. However, this comes at a cost of a reduction in D 90% of the PTV of 10%, which often implies that it drops below the desired minimum of 100%. For (LDV), none of the DTMRs were able to improve high-dose volume measures. DTMRs were not capable of improving robustness of PTV D 90% against uncertainty in dwell positions for both models. (paper)

  16. Multiple-time-stepping generalized hybrid Monte Carlo methods

    Energy Technology Data Exchange (ETDEWEB)

    Escribano, Bruno, E-mail: bescribano@bcamath.org [BCAM—Basque Center for Applied Mathematics, E-48009 Bilbao (Spain); Akhmatskaya, Elena [BCAM—Basque Center for Applied Mathematics, E-48009 Bilbao (Spain); IKERBASQUE, Basque Foundation for Science, E-48013 Bilbao (Spain); Reich, Sebastian [Universität Potsdam, Institut für Mathematik, D-14469 Potsdam (Germany); Azpiroz, Jon M. [Kimika Fakultatea, Euskal Herriko Unibertsitatea (UPV/EHU) and Donostia International Physics Center (DIPC), P.K. 1072, Donostia (Spain)

    2015-01-01

    Performance of the generalized shadow hybrid Monte Carlo (GSHMC) method [1], which proved to be superior in sampling efficiency over its predecessors [2–4], molecular dynamics and hybrid Monte Carlo, can be further improved by combining it with multi-time-stepping (MTS) and mollification of slow forces. We demonstrate that the comparatively simple modifications of the method not only lead to better performance of GSHMC itself but also allow for beating the best performed methods, which use the similar force splitting schemes. In addition we show that the same ideas can be successfully applied to the conventional generalized hybrid Monte Carlo method (GHMC). The resulting methods, MTS-GHMC and MTS-GSHMC, provide accurate reproduction of thermodynamic and dynamical properties, exact temperature control during simulation and computational robustness and efficiency. MTS-GHMC uses a generalized momentum update to achieve weak stochastic stabilization to the molecular dynamics (MD) integrator. MTS-GSHMC adds the use of a shadow (modified) Hamiltonian to filter the MD trajectories in the HMC scheme. We introduce a new shadow Hamiltonian formulation adapted to force-splitting methods. The use of such Hamiltonians improves the acceptance rate of trajectories and has a strong impact on the sampling efficiency of the method. Both methods were implemented in the open-source MD package ProtoMol and were tested on a water and a protein systems. Results were compared to those obtained using a Langevin Molly (LM) method [5] on the same systems. The test results demonstrate the superiority of the new methods over LM in terms of stability, accuracy and sampling efficiency. This suggests that putting the MTS approach in the framework of hybrid Monte Carlo and using the natural stochasticity offered by the generalized hybrid Monte Carlo lead to improving stability of MTS and allow for achieving larger step sizes in the simulation of complex systems.

  17. Aggressive time step selection for the time asymptotic velocity diffusion problem

    International Nuclear Information System (INIS)

    Hewett, D.W.; Krapchev, V.B.; Hizanidis, K.; Bers, A.

    1984-12-01

    An aggressive time step selector for an ADI algorithm is preseneted that is applied to the linearized 2-D Fokker-Planck equation including an externally imposed quasilinear diffusion term. This method provides a reduction in CPU requirements by factors of two or three compared to standard ADI. More important, the robustness of the procedure greatly reduces the work load of the user. The procedure selects a nearly optimal Δt with a minimum of intervention by the user thus relieving the need to supervise the algorithm. In effect, the algorithm does its own supervision by discarding time steps made with Δt too large

  18. THE STANDARD MILLING TIME OF FLAT SURFACES WITHOUT OUTLINE RESTRICTIONS

    Directory of Open Access Journals (Sweden)

    Leszek Skoczylas

    2016-09-01

    Full Text Available Knowing the standard operating times of technological operations is essential element in the business operations of every production enterprise. It is the basis for establishing the production capacity, planning the production schedule, or even calculating costs. The article presents a variety of methods used in the calculation of standard worktime of technological operations. An especially important distinction was made between calculating the total machining time and the actual cutting time. Through the examination of various machined flat surfaces, the results of worktime calculations from CATIA and the authored mathematical model are presented.

  19. Time of Day When Type 1 Diabetes Patients With Eating Disorder Symptoms Most Commonly Restrict Insulin.

    Science.gov (United States)

    Merwin, Rhonda M; Moskovich, Ashley A; Honeycutt, Lisa K; Lane, James D; Feinglos, Mark; Surwit, Richard S; Zucker, Nancy L; Dmitrieva, Natalia O; Babyak, Michael A; Batchelder, Heather; Mooney, Jan

    Restricting insulin to lose weight is a significant problem in the clinical management of type 1 diabetes (T1D). Little is known about this behavior or how to effectively intervene. Identifying when insulin restriction occurs could allow clinicians to target typical high-risk times or formulate hypotheses regarding factors that influence this behavior. The current study investigated the frequency of insulin restriction by time of day. Fifty-nine adults with T1D and eating disorder symptoms completed 72 hours of real-time reporting of eating and insulin dosing with continuous glucose monitoring. We used a generalized estimating equation model to test the global hypothesis that frequency of insulin restriction (defined as not taking enough insulin to cover food consumed) varied by time of day, and examined frequency of insulin restriction by hour. We also examined whether patterns of insulin restriction for 72 hours corresponded with patients' interview reports of insulin restriction for the past 28 days. Frequency of insulin restriction varied as a function of time (p = .016). Insulin restriction was the least likely in the morning hours (6:00-8:59 AM), averaging 6% of the meals/snacks consumed. Insulin restriction was more common in the late afternoon (3:00-5:59 PM), peaking at 29%. Insulin was restricted for 32% of the meals/snacks eaten overnight (excluding for hypoglycemia); however, overnight eating was rare. Insulin restriction was associated with higher 120-minute postprandial blood glucose (difference = 44.4 mg/dL, 95% confidence interval = 22.7-68.5, p < .001) and overall poorer metabolic control (r = 0.43-0.62, p's < .01). Patients reported restricting insulin for a greater percentage of meals and snacks for the past 28 days than during the 72 hour real-time assessment; however, the reports were correlated (Spearman's ρ = 0.46, p < .001) and accounted for similar variance in HbA1c (34% versus 35%, respectively). Findings suggest that insulin restriction

  20. The family context of low-income parents who restrict child screen time.

    Science.gov (United States)

    Lampard, Amy M; Jurkowski, Janine M; Davison, Kirsten K

    2013-10-01

    The American Academy of Pediatrics recommends that parents restrict child screen time to two hours per day, but many preschool-aged children exceed this viewing recommendation. Modifying children's viewing habits will require collaborating with parents, but little is known about the factors that influence parents' capacity for effective screen-related parenting. This study aimed to identify the demographic, family and community contextual factors associated with low-income parents' restriction of child screen time. Parents (N=146) of children (age 2-5 years) attending Head Start centers in the United States completed a self-report survey in 2010 assessing parent and child screen use (television, DVD, video, video games, and leisure-time computer use), parent restriction of child screen time, and family (parent stress, social support, and life pressures) and community (neighborhood safety and social capital) factors. Children were more likely to meet the American Academy of Pediatrics screen time recommendation if their parent reported high restriction of child screen time. Parent and child demographic characteristics were not associated with parents' restriction of child screen time. In multivariate analysis, less parent screen time, fewer parent life pressures, and greater social support were associated with parents' high restriction of screen time. Family contextual factors may play an important role in enabling low-income parents to restrict their children's screen time. When counseling low-income parents about the importance of restricting child screen time, practitioners should be sensitive to family contextual factors that may influence parents' capacity to implement this behavior change.

  1. Circadian rhythms, time-restricted feeding, and healthy aging.

    Science.gov (United States)

    Manoogian, Emily N C; Panda, Satchidananda

    2017-10-01

    Circadian rhythms optimize physiology and health by temporally coordinating cellular function, tissue function, and behavior. These endogenous rhythms dampen with age and thus compromise temporal coordination. Feeding-fasting patterns are an external cue that profoundly influence the robustness of daily biological rhythms. Erratic eating patterns can disrupt the temporal coordination of metabolism and physiology leading to chronic diseases that are also characteristic of aging. However, sustaining a robust feeding-fasting cycle, even without altering nutrition quality or quantity, can prevent or reverse these chronic diseases in experimental models. In humans, epidemiological studies have shown erratic eating patterns increase the risk of disease, whereas sustained feeding-fasting cycles, or prolonged overnight fasting, is correlated with protection from breast cancer. Therefore, optimizing the timing of external cues with defined eating patterns can sustain a robust circadian clock, which may prevent disease and improve prognosis. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Stability of the high-order finite elements for acoustic or elastic wave propagation with high-order time stepping

    KAUST Repository

    De Basabe, Jonás D.

    2010-04-01

    We investigate the stability of some high-order finite element methods, namely the spectral element method and the interior-penalty discontinuous Galerkin method (IP-DGM), for acoustic or elastic wave propagation that have become increasingly popular in the recent past. We consider the Lax-Wendroff method (LWM) for time stepping and show that it allows for a larger time step than the classical leap-frog finite difference method, with higher-order accuracy. In particular the fourth-order LWM allows for a time step 73 per cent larger than that of the leap-frog method; the computational cost is approximately double per time step, but the larger time step partially compensates for this additional cost. Necessary, but not sufficient, stability conditions are given for the mentioned methods for orders up to 10 in space and time. The stability conditions for IP-DGM are approximately 20 and 60 per cent more restrictive than those for SEM in the acoustic and elastic cases, respectively. © 2010 The Authors Journal compilation © 2010 RAS.

  3. Perturbed Strong Stability Preserving Time-Stepping Methods For Hyperbolic PDEs

    KAUST Repository

    Hadjimichael, Yiannis

    2017-09-30

    A plethora of physical phenomena are modelled by hyperbolic partial differential equations, for which the exact solution is usually not known. Numerical methods are employed to approximate the solution to hyperbolic problems; however, in many cases it is difficult to satisfy certain physical properties while maintaining high order of accuracy. In this thesis, we develop high-order time-stepping methods that are capable of maintaining stability constraints of the solution, when coupled with suitable spatial discretizations. Such methods are called strong stability preserving (SSP) time integrators, and we mainly focus on perturbed methods that use both upwind- and downwind-biased spatial discretizations. Firstly, we introduce a new family of third-order implicit Runge–Kuttas methods with arbitrarily large SSP coefficient. We investigate the stability and accuracy of these methods and we show that they perform well on hyperbolic problems with large CFL numbers. Moreover, we extend the analysis of SSP linear multistep methods to semi-discretized problems for which different terms on the right-hand side of the initial value problem satisfy different forward Euler (or circle) conditions. Optimal perturbed and additive monotonicity-preserving linear multistep methods are studied in the context of such problems. Optimal perturbed methods attain augmented monotonicity-preserving step sizes when the different forward Euler conditions are taken into account. On the other hand, we show that optimal SSP additive methods achieve a monotonicity-preserving step-size restriction no better than that of the corresponding non-additive SSP linear multistep methods. Furthermore, we develop the first SSP linear multistep methods of order two and three with variable step size, and study their optimality. We describe an optimal step-size strategy and demonstrate the effectiveness of these methods on various one- and multi-dimensional problems. Finally, we establish necessary conditions

  4. 5 CFR 330.504 - Special restrictions after appointment under Part-time Direct Hire Program.

    Science.gov (United States)

    2010-01-01

    ... under Part-time Direct Hire Program. 330.504 Section 330.504 Administrative Personnel OFFICE OF... To Protect Competitive Principles § 330.504 Special restrictions after appointment under Part-time Direct Hire Program. (a) A person hired under the Part-time Direct Hire Program may not be changed to...

  5. Coherent states for the time dependent harmonic oscillator: the step function

    International Nuclear Information System (INIS)

    Moya-Cessa, Hector; Fernandez Guasti, Manuel

    2003-01-01

    We study the time evolution for the quantum harmonic oscillator subjected to a sudden change of frequency. It is based on an approximate analytic solution to the time dependent Ermakov equation for a step function. This approach allows for a continuous treatment that differs from former studies that involve the matching of two time independent solutions at the time when the step occurs

  6. Social-cognitive predictors of low-income parents' restriction of screen time among preschool-aged children.

    Science.gov (United States)

    Lampard, Amy M; Jurkowski, Janine M; Davison, Kirsten K

    2013-10-01

    Parents' rules regarding child television, DVD, video game, and computer use (screen time) have been associated with lower screen use in children. This study aimed to identify modifiable correlates of this behavior by examining social-cognitive predictors of parents' restriction of child screen time. Low-income parents (N = 147) of preschool-aged children (2-6 years) completed self-administered questionnaires examining parent and child screen time, parent restriction of screen time, self-efficacy to restrict screen time, and beliefs about screen time. Structural equation modeling results indicated that greater self-efficacy to restrict screen time (β = .29, p = .016) and greater perceived importance of restricting child screen use (β = .55, p < .001) were associated with greater restriction of child screen use, after controlling for parent screen time. Family-based interventions that consider broader attitudinal factors around child screen time may be necessary to engage parents in restricting screen use.

  7. How is adults' screen time behaviour influencing their views on screen time restrictions for children? A cross-sectional study.

    Science.gov (United States)

    Schoeppe, Stephanie; Rebar, Amanda L; Short, Camille E; Alley, Stephanie; Van Lippevelde, Wendy; Vandelanotte, Corneel

    2016-03-01

    High screen time in children and its detrimental health effects is a major public health problem. How much screen time adults think is appropriate for children remains little explored, as well as whether adults' screen time behaviour would determine their views on screen time restrictions for children. This study aimed to investigate how adults' screen time behaviour influences their views on screen time restrictions for children, including differences by gender and parental status. In 2013, 2034 Australian adults participated in an online survey conducted by the Population Research Laboratory at Central Queensland University, Rockhampton. Adult screen time behaviour was assessed using the Workforce Sitting Questionnaire. Adults reported the maximum time children aged between 5-12 years should be allowed to spend watching TV and using a computer. Ordinal logistic regression was used to compare adult screen time behaviour with views on screen time restrictions for children. Most adults (68%) held the view that children should be allowed no more than 2 h of TV viewing and computer use on school days, whilst fewer adults (44%) thought this screen time limit is needed on weekend days. Women would impose higher screen time restrictions for children than men (p 2 h on watching TV and using the computer at home on work days (66%) and non-work days (88%). Adults spending ≤ 2 h/day in leisure-related screen time were less likely to permit children > 2 h/day of screen time. These associations did not differ by adult gender and parental status. Most adults think it is appropriate to limit children's screen time to the recommended ≤ 2 h/day but few adults themselves adhere to this screen time limit. Adults with lower screen use may be more inclined to limit children's screen time. Strategies to reduce screen time in children may also need to target adult screen use.

  8. Simple, specific molecular typing of dengue virus isolates using one-step RT-PCR and restriction fragment length polymorphism.

    Science.gov (United States)

    Ortiz, Alma; Capitan, Zeuz; Mendoza, Yaxelis; Cisneros, Julio; Moreno, Brechla; Zaldivar, Yamitzel; Garcia, Mariana; Smith, Rebecca E; Motta, Jorge; Pascale, Juan Miguel

    2012-10-01

    A one-step RT-PCR and one-enzyme RFLP was used to detect and distinguish among flaviviruses, including the four serotypes of dengue and the St. Louis Encephalitis, West Nile and Yellow Fever viruses in cultured virus samples or acute-phase human serum. Using a previously described RT-PCR, but novel RFLP procedure, results are obtained in 24 h with basic PCR and electrophoresis equipment. There is 95% agreement between RT-PCR/RFLP results and those achieved by indirect immunofluorescence assays, and 100% agreement between RT-PCR/RFLP results and gene sequencing. This method is more rapid than tests of cytopathic effect based on virus isolation in tissue culture, and simpler than real-time PCR. It does not require specialized equipment, radioisotopes or computer analysis and is a method that can be applied widely in the developing world. It allows for prompt determination of whether a flavivirus is the cause of illness in a febrile patient, rapid identification of dengue serotypes in circulation, and improved patient management in cases where prior dengue exposure make dengue hemorrhagic fever or dengue shock syndrome a risk. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. A positive and multi-element conserving time stepping scheme for biogeochemical processes in marine ecosystem models

    Science.gov (United States)

    Radtke, H.; Burchard, H.

    2015-01-01

    In this paper, an unconditionally positive and multi-element conserving time stepping scheme for systems of non-linearly coupled ODE's is presented. These systems of ODE's are used to describe biogeochemical transformation processes in marine ecosystem models. The numerical scheme is a positive-definite modification of the Runge-Kutta method, it can have arbitrarily high order of accuracy and does not require time step adaption. If the scheme is combined with a modified Patankar-Runge-Kutta method from Burchard et al. (2003), it also gets the ability to solve a certain class of stiff numerical problems, but the accuracy is restricted to second-order then. The performance of the new scheme on two test case problems is shown.

  10. Formulation of an explicit-multiple-time-step time integration method for use in a global primitive equation grid model

    Science.gov (United States)

    Chao, W. C.

    1982-01-01

    With appropriate modifications, a recently proposed explicit-multiple-time-step scheme (EMTSS) is incorporated into the UCLA model. In this scheme, the linearized terms in the governing equations that generate the gravity waves are split into different vertical modes. Each mode is integrated with an optimal time step, and at periodic intervals these modes are recombined. The other terms are integrated with a time step dictated by the CFL condition for low-frequency waves. This large time step requires a special modification of the advective terms in the polar region to maintain stability. Test runs for 72 h show that EMTSS is a stable, efficient and accurate scheme.

  11. Solving point reactor kinetic equations by time step-size adaptable numerical methods

    International Nuclear Information System (INIS)

    Liao Chaqing

    2007-01-01

    Based on the analysis of effects of time step-size on numerical solutions, this paper showed the necessity of step-size adaptation. Based on the relationship between error and step-size, two-step adaptation methods for solving initial value problems (IVPs) were introduced. They are Two-Step Method and Embedded Runge-Kutta Method. PRKEs were solved by implicit Euler method with step-sizes optimized by using Two-Step Method. It was observed that the control error has important influence on the step-size and the accuracy of solutions. With suitable control errors, the solutions of PRKEs computed by the above mentioned method are accurate reasonably. The accuracy and usage of MATLAB built-in ODE solvers ode23 and ode45, both of which adopt Runge-Kutta-Fehlberg method, were also studied and discussed. (authors)

  12. Simultaneous Optimization of Container Ship Sailing Speed and Container Routing with Transit Time Restrictions

    DEFF Research Database (Denmark)

    Karsten, Christian Vad; Røpke, Stefan; Pisinger, David

    We introduce a decision support tool for liner shipping companies to optimally determine the sailing speed and needed fleet for a global network. As a novelty we incorporate cargo routing decisions with tight transit time restrictions on each container such that we get a realistic picture...

  13. Sleep restriction may lead to disruption in physiological attention and reaction time

    Directory of Open Access Journals (Sweden)

    Arbind Kumar Choudhary

    2016-07-01

    Full Text Available Sleepiness is the condition where for some reason fails to go into a sleep state and will have difficulty in remaining awake even while carrying out activities. Sleep restriction occurs when an individual fails to get enough sleep due to high work demands. The mechanism between sleep restriction and underlying brain physiology deficits is not well assumed. The objective of the present study was to investigate the mental attention (P300 and reaction time [visual (VRT and auditory (ART] among night watchmen, at subsequent; first (1st day, fourth (4th day and seventh (7th day of restricted sleep period. After exclusion and inclusion criteria, the study was performed among 50 watchmen (age=18–35 years (n=50 after providing written informed consent and divided into two group. Group I-(Normal sleep (n=28 working in day time and used to have normal sleep in night (≥8 h; Group II-(Restricted sleep (n=22 - working in night time and used to have less sleep in night (≤3 h. Statistical significance between the different groups was determined by the independent student ʻtʼ test and the significance level was fixed at p≤0.05. We observed that among all normal and restricted sleep watchmen there was not any significant variation in Karolinska Sleepiness Scale (KSS score, VRT and ART, along with latency and amplitude of P300 on 1st day of restricted sleep. However at subsequent on 4th day and 7th day of restricted sleep, there was significant increase in (KSSscore, and prolongation of VRT and ART as well as alteration in latency and amplitude of P300 wave in restricted sleep watchmen when compare to normal sleep watchmen. The present finding concludes that loss of sleep has major impact in dynamic change in mental attention and reaction time among watchmen employed in night shift. Professional regulations and work schedules should integrate sleep schedules before and during the work period as an essential dimension for their healthy life.

  14. Sleep restriction may lead to disruption in physiological attention and reaction time.

    Science.gov (United States)

    Choudhary, Arbind Kumar; Kishanrao, Sadawarte Sahebrao; Dadarao Dhanvijay, Anup Kumar; Alam, Tanwir

    2016-01-01

    Sleepiness is the condition where for some reason fails to go into a sleep state and will have difficulty in remaining awake even while carrying out activities. Sleep restriction occurs when an individual fails to get enough sleep due to high work demands. The mechanism between sleep restriction and underlying brain physiology deficits is not well assumed. The objective of the present study was to investigate the mental attention (P300) and reaction time [visual (VRT) and auditory (ART)] among night watchmen, at subsequent; first (1st) day, fourth (4th) day and seventh (7th) day of restricted sleep period. After exclusion and inclusion criteria, the study was performed among 50 watchmen (age=18-35 years) (n=50) after providing written informed consent and divided into two group. Group I-(Normal sleep) (n=28) working in day time and used to have normal sleep in night (≥8 h); Group II-(Restricted sleep) (n=22) - working in night time and used to have less sleep in night (≤3 h). Statistical significance between the different groups was determined by the independent student ' t ' test and the significance level was fixed at p≤0.05. We observed that among all normal and restricted sleep watchmen there was not any significant variation in Karolinska Sleepiness Scale (KSS) score, VRT and ART, along with latency and amplitude of P300 on 1st day of restricted sleep. However at subsequent on 4th day and 7th day of restricted sleep, there was significant increase in (KSS)score, and prolongation of VRT and ART as well as alteration in latency and amplitude of P300 wave in restricted sleep watchmen when compare to normal sleep watchmen. The present finding concludes that loss of sleep has major impact in dynamic change in mental attention and reaction time among watchmen employed in night shift. Professional regulations and work schedules should integrate sleep schedules before and during the work period as an essential dimension for their healthy life.

  15. On an efficient multiple time step Monte Carlo simulation of the SABR model

    NARCIS (Netherlands)

    Leitao Rodriguez, A.; Grzelak, L.A.; Oosterlee, C.W.

    2017-01-01

    In this paper, we will present a multiple time step Monte Carlo simulation technique for pricing options under the Stochastic Alpha Beta Rho model. The proposed method is an extension of the one time step Monte Carlo method that we proposed in an accompanying paper Leitao et al. [Appl. Math.

  16. An adaptive time-stepping strategy for solving the phase field crystal model

    International Nuclear Information System (INIS)

    Zhang, Zhengru; Ma, Yuan; Qiao, Zhonghua

    2013-01-01

    In this work, we will propose an adaptive time step method for simulating the dynamics of the phase field crystal (PFC) model. The numerical simulation of the PFC model needs long time to reach steady state, and then large time-stepping method is necessary. Unconditionally energy stable schemes are used to solve the PFC model. The time steps are adaptively determined based on the time derivative of the corresponding energy. It is found that the use of the proposed time step adaptivity cannot only resolve the steady state solution, but also the dynamical development of the solution efficiently and accurately. The numerical experiments demonstrate that the CPU time is significantly saved for long time simulations

  17. How is adults’ screen time behaviour influencing their views on screen time restrictions for children? A cross-sectional study

    Directory of Open Access Journals (Sweden)

    Stephanie Schoeppe

    2016-03-01

    Full Text Available Abstract Background High screen time in children and its detrimental health effects is a major public health problem. How much screen time adults think is appropriate for children remains little explored, as well as whether adults’ screen time behaviour would determine their views on screen time restrictions for children. This study aimed to investigate how adults’ screen time behaviour influences their views on screen time restrictions for children, including differences by gender and parental status. Methods In 2013, 2034 Australian adults participated in an online survey conducted by the Population Research Laboratory at Central Queensland University, Rockhampton. Adult screen time behaviour was assessed using the Workforce Sitting Questionnaire. Adults reported the maximum time children aged between 5–12 years should be allowed to spend watching TV and using a computer. Ordinal logistic regression was used to compare adult screen time behaviour with views on screen time restrictions for children. Results Most adults (68 % held the view that children should be allowed no more than 2 h of TV viewing and computer use on school days, whilst fewer adults (44 % thought this screen time limit is needed on weekend days. Women would impose higher screen time restrictions for children than men (p  2 h on watching TV and using the computer at home on work days (66 % and non-work days (88 %. Adults spending ≤ 2 h/day in leisure-related screen time were less likely to permit children > 2 h/day of screen time. These associations did not differ by adult gender and parental status. Conclusions Most adults think it is appropriate to limit children’s screen time to the recommended ≤ 2 h/day but few adults themselves adhere to this screen time limit. Adults with lower screen use may be more inclined to limit children’s screen time. Strategies to reduce screen time in children may also need to target adult screen use.

  18. Adaptive Time Stepping for Transient Network Flow Simulation in Rocket Propulsion Systems

    Science.gov (United States)

    Majumdar, Alok K.; Ravindran, S. S.

    2017-01-01

    Fluid and thermal transients found in rocket propulsion systems such as propellant feedline system is a complex process involving fast phases followed by slow phases. Therefore their time accurate computation requires use of short time step initially followed by the use of much larger time step. Yet there are instances that involve fast-slow-fast phases. In this paper, we present a feedback control based adaptive time stepping algorithm, and discuss its use in network flow simulation of fluid and thermal transients. The time step is automatically controlled during the simulation by monitoring changes in certain key variables and by feedback. In order to demonstrate the viability of time adaptivity for engineering problems, we applied it to simulate water hammer and cryogenic chill down in pipelines. Our comparison and validation demonstrate the accuracy and efficiency of this adaptive strategy.

  19. GOTHIC: Gravitational oct-tree code accelerated by hierarchical time step controlling

    Science.gov (United States)

    Miki, Yohei; Umemura, Masayuki

    2017-04-01

    The tree method is a widely implemented algorithm for collisionless N-body simulations in astrophysics well suited for GPU(s). Adopting hierarchical time stepping can accelerate N-body simulations; however, it is infrequently implemented and its potential remains untested in GPU implementations. We have developed a Gravitational Oct-Tree code accelerated by HIerarchical time step Controlling named GOTHIC, which adopts both the tree method and the hierarchical time step. The code adopts some adaptive optimizations by monitoring the execution time of each function on-the-fly and minimizes the time-to-solution by balancing the measured time of multiple functions. Results of performance measurements with realistic particle distribution performed on NVIDIA Tesla M2090, K20X, and GeForce GTX TITAN X, which are representative GPUs of the Fermi, Kepler, and Maxwell generation of GPUs, show that the hierarchical time step achieves a speedup by a factor of around 3-5 times compared to the shared time step. The measured elapsed time per step of GOTHIC is 0.30 s or 0.44 s on GTX TITAN X when the particle distribution represents the Andromeda galaxy or the NFW sphere, respectively, with 224 = 16,777,216 particles. The averaged performance of the code corresponds to 10-30% of the theoretical single precision peak performance of the GPU.

  20. Some Comments on the Behavior of the RELAP5 Numerical Scheme at Very Small Time Steps

    International Nuclear Information System (INIS)

    Tiselj, Iztok; Cerne, Gregor

    2000-01-01

    The behavior of the RELAP5 code at very short time steps is described, i.e., δt [approximately equal to] 0.01 δx/c. First, the property of the RELAP5 code to trace acoustic waves with 'almost' second-order accuracy is demonstrated. Quasi-second-order accuracy is usually achieved for acoustic waves at very short time steps but can never be achieved for the propagation of nonacoustic temperature and void fraction waves. While this feature may be beneficial for the simulations of fast transients describing pressure waves, it also has an adverse effect: The lack of numerical diffusion at very short time steps can cause typical second-order numerical oscillations near steep pressure jumps. This behavior explains why an automatic halving of the time step, which is used in RELAP5 when numerical difficulties are encountered, in some cases leads to the failure of the simulation.Second, the integration of the stiff interphase exchange terms in RELAP5 is studied. For transients with flashing and/or rapid condensation as the main phenomena, results strongly depend on the time step used. Poor accuracy is achieved with 'normal' time steps (δt [approximately equal to] δx/v) because of the very short characteristic timescale of the interphase mass and heat transfer sources. In such cases significantly different results are predicted with very short time steps because of the more accurate integration of the stiff interphase exchange terms

  1. Molecular dynamics based enhanced sampling of collective variables with very large time steps

    Science.gov (United States)

    Chen, Pei-Yang; Tuckerman, Mark E.

    2018-01-01

    Enhanced sampling techniques that target a set of collective variables and that use molecular dynamics as the driving engine have seen widespread application in the computational molecular sciences as a means to explore the free-energy landscapes of complex systems. The use of molecular dynamics as the fundamental driver of the sampling requires the introduction of a time step whose magnitude is limited by the fastest motions in a system. While standard multiple time-stepping methods allow larger time steps to be employed for the slower and computationally more expensive forces, the maximum achievable increase in time step is limited by resonance phenomena, which inextricably couple fast and slow motions. Recently, we introduced deterministic and stochastic resonance-free multiple time step algorithms for molecular dynamics that solve this resonance problem and allow ten- to twenty-fold gains in the large time step compared to standard multiple time step algorithms [P. Minary et al., Phys. Rev. Lett. 93, 150201 (2004); B. Leimkuhler et al., Mol. Phys. 111, 3579-3594 (2013)]. These methods are based on the imposition of isokinetic constraints that couple the physical system to Nosé-Hoover chains or Nosé-Hoover Langevin schemes. In this paper, we show how to adapt these methods for collective variable-based enhanced sampling techniques, specifically adiabatic free-energy dynamics/temperature-accelerated molecular dynamics, unified free-energy dynamics, and by extension, metadynamics, thus allowing simulations employing these methods to employ similarly very large time steps. The combination of resonance-free multiple time step integrators with free-energy-based enhanced sampling significantly improves the efficiency of conformational exploration.

  2. Errors in Postural Preparation Lead to Increased Choice Reaction Times for Step Initiation in Older Adults

    Science.gov (United States)

    Nutt, John G.; Horak, Fay B.

    2011-01-01

    Background. This study asked whether older adults were more likely than younger adults to err in the initial direction of their anticipatory postural adjustment (APA) prior to a step (indicating a motor program error), whether initial motor program errors accounted for reaction time differences for step initiation, and whether initial motor program errors were linked to inhibitory failure. Methods. In a stepping task with choice reaction time and simple reaction time conditions, we measured forces under the feet to quantify APA onset and step latency and we used body kinematics to quantify forward movement of center of mass and length of first step. Results. Trials with APA errors were almost three times as common for older adults as for younger adults, and they were nine times more likely in choice reaction time trials than in simple reaction time trials. In trials with APA errors, step latency was delayed, correlation between APA onset and step latency was diminished, and forward motion of the center of mass prior to the step was increased. Participants with more APA errors tended to have worse Stroop interference scores, regardless of age. Conclusions. The results support the hypothesis that findings of slow choice reaction time step initiation in older adults are attributable to inclusion of trials with incorrect initial motor preparation and that these errors are caused by deficits in response inhibition. By extension, the results also suggest that mixing of trials with correct and incorrect initial motor preparation might explain apparent choice reaction time slowing with age in upper limb tasks. PMID:21498431

  3. One-step electrodeposition process of CuInSe2: Deposition time effect

    Indian Academy of Sciences (India)

    Administrator

    CuInSe2 thin films were prepared by one-step electrodeposition process using a simplified two- electrodes system. ... homojunctions or heterojunctions (Rincon et al 1983). Efficiency of ... deposition times onto indium thin oxide (ITO)-covered.

  4. Error Analysis of a Fractional Time-Stepping Technique for Incompressible Flows with Variable Density

    KAUST Repository

    Guermond, J.-L.; Salgado, Abner J.

    2011-01-01

    In this paper we analyze the convergence properties of a new fractional time-stepping technique for the solution of the variable density incompressible Navier-Stokes equations. The main feature of this method is that, contrary to other existing algorithms, the pressure is determined by just solving one Poisson equation per time step. First-order error estimates are proved, and stability of a formally second-order variant of the method is established. © 2011 Society for Industrial and Applied Mathematics.

  5. Heuristics for the Economic Production Quantity Problem under Restrictions on Production and Maintenance Time

    Directory of Open Access Journals (Sweden)

    Qi Xu

    2016-01-01

    Full Text Available This paper proposes an economic production quantity problem with the maximal production run time and minimal preventive maintenance time over a finite planning horizon. The objective is to find the efficient production and maintenance policy to minimize the total cost composed of production, maintenance, shortages, and holding costs under the restriction on the production run time and the preventive maintenance time. The production and maintenance decisions include the production and maintenance frequencies and the production run and the maintenance time. The variability and the boundedness of the production run and maintenance time make the problem difficult to solve. Two heuristic algorithms are developed using different techniques based on the optimal properties of the relaxed problem. The performance comparison between the two algorithms is illustrated by numerical examples. The numerical results show that, for the most part, there exists a heuristic algorithm which is more effective than the other.

  6. A stabilized Runge–Kutta–Legendre method for explicit super-time-stepping of parabolic and mixed equations

    International Nuclear Information System (INIS)

    Meyer, Chad D.; Balsara, Dinshaw S.; Aslam, Tariq D.

    2014-01-01

    Parabolic partial differential equations appear in several physical problems, including problems that have a dominant hyperbolic part coupled to a sub-dominant parabolic component. Explicit methods for their solution are easy to implement but have very restrictive time step constraints. Implicit solution methods can be unconditionally stable but have the disadvantage of being computationally costly or difficult to implement. Super-time-stepping methods for treating parabolic terms in mixed type partial differential equations occupy an intermediate position. In such methods each superstep takes “s” explicit Runge–Kutta-like time-steps to advance the parabolic terms by a time-step that is s 2 times larger than a single explicit time-step. The expanded stability is usually obtained by mapping the short recursion relation of the explicit Runge–Kutta scheme to the recursion relation of some well-known, stable polynomial. Prior work has built temporally first- and second-order accurate super-time-stepping methods around the recursion relation associated with Chebyshev polynomials. Since their stability is based on the boundedness of the Chebyshev polynomials, these methods have been called RKC1 and RKC2. In this work we build temporally first- and second-order accurate super-time-stepping methods around the recursion relation associated with Legendre polynomials. We call these methods RKL1 and RKL2. The RKL1 method is first-order accurate in time; the RKL2 method is second-order accurate in time. We verify that the newly-designed RKL1 and RKL2 schemes have a very desirable monotonicity preserving property for one-dimensional problems – a solution that is monotone at the beginning of a time step retains that property at the end of that time step. It is shown that RKL1 and RKL2 methods are stable for all values of the diffusion coefficient up to the maximum value. We call this a convex monotonicity preserving property and show by examples that it is very useful

  7. Dissolvable fluidic time delays for programming multi-step assays in instrument-free paper diagnostics.

    Science.gov (United States)

    Lutz, Barry; Liang, Tinny; Fu, Elain; Ramachandran, Sujatha; Kauffman, Peter; Yager, Paul

    2013-07-21

    Lateral flow tests (LFTs) are an ingenious format for rapid and easy-to-use diagnostics, but they are fundamentally limited to assay chemistries that can be reduced to a single chemical step. In contrast, most laboratory diagnostic assays rely on multiple timed steps carried out by a human or a machine. Here, we use dissolvable sugar applied to paper to create programmable flow delays and present a paper network topology that uses these time delays to program automated multi-step fluidic protocols. Solutions of sucrose at different concentrations (10-70% of saturation) were added to paper strips and dried to create fluidic time delays spanning minutes to nearly an hour. A simple folding card format employing sugar delays was shown to automate a four-step fluidic process initiated by a single user activation step (folding the card); this device was used to perform a signal-amplified sandwich immunoassay for a diagnostic biomarker for malaria. The cards are capable of automating multi-step assay protocols normally used in laboratories, but in a rapid, low-cost, and easy-to-use format.

  8. Time step rescaling recovers continuous-time dynamical properties for discrete-time Langevin integration of nonequilibrium systems.

    Science.gov (United States)

    Sivak, David A; Chodera, John D; Crooks, Gavin E

    2014-06-19

    When simulating molecular systems using deterministic equations of motion (e.g., Newtonian dynamics), such equations are generally numerically integrated according to a well-developed set of algorithms that share commonly agreed-upon desirable properties. However, for stochastic equations of motion (e.g., Langevin dynamics), there is still broad disagreement over which integration algorithms are most appropriate. While multiple desiderata have been proposed throughout the literature, consensus on which criteria are important is absent, and no published integration scheme satisfies all desiderata simultaneously. Additional nontrivial complications stem from simulating systems driven out of equilibrium using existing stochastic integration schemes in conjunction with recently developed nonequilibrium fluctuation theorems. Here, we examine a family of discrete time integration schemes for Langevin dynamics, assessing how each member satisfies a variety of desiderata that have been enumerated in prior efforts to construct suitable Langevin integrators. We show that the incorporation of a novel time step rescaling in the deterministic updates of position and velocity can correct a number of dynamical defects in these integrators. Finally, we identify a particular splitting (related to the velocity Verlet discretization) that has essentially universally appropriate properties for the simulation of Langevin dynamics for molecular systems in equilibrium, nonequilibrium, and path sampling contexts.

  9. Time-frequency analysis of the restricted three-body problem: transport and resonance transitions

    International Nuclear Information System (INIS)

    Vela-Arevalo, Luz V; Marsden, Jerrold E

    2004-01-01

    A method of time-frequency analysis based on wavelets is applied to the problem of transport between different regions of the solar system, using the model of the circular restricted three-body problem in both the planar and the spatial versions of the problem. The method is based on the extraction of instantaneous frequencies from the wavelet transform of numerical solutions. Time-varying frequencies provide a good diagnostic tool to discern chaotic trajectories from regular ones, and we can identify resonance islands that greatly affect the dynamics. Good accuracy in the calculation of time-varying frequencies allows us to determine resonance trappings of chaotic trajectories and resonance transitions. We show the relation between resonance transitions and transport in different regions of the phase space

  10. Time dependent theory of two-step absorption of two pulses

    Energy Technology Data Exchange (ETDEWEB)

    Rebane, Inna, E-mail: inna.rebane@ut.ee

    2015-09-25

    The time dependent theory of two step-absorption of two different light pulses with arbitrary duration in the electronic three-level model is proposed. The probability that the third level is excited at the moment t is found in depending on the time delay between pulses, the spectral widths of the pulses and the energy relaxation constants of the excited electronic levels. The time dependent perturbation theory is applied without using “doorway–window” approach. The time and spectral behavior of the spectrum using in calculations as simple as possible model is analyzed. - Highlights: • Time dependent theory of two-step absorption in the three-level model is proposed. • Two different light pulses with arbitrary duration is observed. • The time dependent perturbation theory is applied without “door–window” approach. • The time and spectral behavior of the spectra is analyzed for several cases.

  11. The hyperbolic step potential: Anti-bound states, SUSY partners and Wigner time delays

    Energy Technology Data Exchange (ETDEWEB)

    Gadella, M. [Departamento de Física Teórica, Atómica y Óptica and IMUVA, Universidad de Valladolid, E-47011 Valladolid (Spain); Kuru, Ş. [Department of Physics, Faculty of Science, Ankara University, 06100 Ankara (Turkey); Negro, J., E-mail: jnegro@fta.uva.es [Departamento de Física Teórica, Atómica y Óptica and IMUVA, Universidad de Valladolid, E-47011 Valladolid (Spain)

    2017-04-15

    We study the scattering produced by a one dimensional hyperbolic step potential, which is exactly solvable and shows an unusual interest because of its asymmetric character. The analytic continuation of the scattering matrix in the momentum representation has a branch cut and an infinite number of simple poles on the negative imaginary axis which are related with the so called anti-bound states. This model does not show resonances. Using the wave functions of the anti-bound states, we obtain supersymmetric (SUSY) partners which are the series of Rosen–Morse II potentials. We have computed the Wigner reflection and transmission time delays for the hyperbolic step and such SUSY partners. Our results show that the more bound states a partner Hamiltonian has the smaller is the time delay. We also have evaluated time delays for the hyperbolic step potential in the classical case and have obtained striking similitudes with the quantum case. - Highlights: • The scattering matrix of hyperbolic step potential is studied. • The scattering matrix has a branch cut and an infinite number of poles. • The poles are associated to anti-bound states. • Susy partners using antibound states are computed. • Wigner time delays for the hyperbolic step and partner potentials are compared.

  12. Modified Pressure-Correction Projection Methods: Open Boundary and Variable Time Stepping

    KAUST Repository

    Bonito, Andrea

    2014-10-31

    © Springer International Publishing Switzerland 2015. In this paper, we design and study two modifications of the first order standard pressure increment projection scheme for the Stokes system. The first scheme improves the existing schemes in the case of open boundary condition by modifying the pressure increment boundary condition, thereby minimizing the pressure boundary layer and recovering the optimal first order decay. The second scheme allows for variable time stepping. It turns out that the straightforward modification to variable time stepping leads to unstable schemes. The proposed scheme is not only stable but also exhibits the optimal first order decay. Numerical computations illustrating the theoretical estimates are provided for both new schemes.

  13. Modified Pressure-Correction Projection Methods: Open Boundary and Variable Time Stepping

    KAUST Repository

    Bonito, Andrea; Guermond, Jean-Luc; Lee, Sanghyun

    2014-01-01

    © Springer International Publishing Switzerland 2015. In this paper, we design and study two modifications of the first order standard pressure increment projection scheme for the Stokes system. The first scheme improves the existing schemes in the case of open boundary condition by modifying the pressure increment boundary condition, thereby minimizing the pressure boundary layer and recovering the optimal first order decay. The second scheme allows for variable time stepping. It turns out that the straightforward modification to variable time stepping leads to unstable schemes. The proposed scheme is not only stable but also exhibits the optimal first order decay. Numerical computations illustrating the theoretical estimates are provided for both new schemes.

  14. Optimal order and time-step criterion for Aarseth-type N-body integrators

    International Nuclear Information System (INIS)

    Makino, Junichiro

    1991-01-01

    How the selection of the time-step criterion and the order of the integrator change the efficiency of Aarseth-type N-body integrators is discussed. An alternative to Aarseth's scheme based on the direct calculation of the time derivative of the force using the Hermite interpolation is compared to Aarseth's scheme, which uses the Newton interpolation to construct the predictor and corrector. How the number of particles in the system changes the behavior of integrators is examined. The Hermite scheme allows a time step twice as large as that for the standard Aarseth scheme for the same accuracy. The calculation cost of the Hermite scheme per time step is roughly twice as much as that of the standard Aarseth scheme. The optimal order of the integrators depends on both the particle number and the accuracy required. The time-step criterion of the standard Aarseth scheme is found to be inapplicable to higher-order integrators, and a more uniformly reliable criterion is proposed. 18 refs

  15. The large discretization step method for time-dependent partial differential equations

    Science.gov (United States)

    Haras, Zigo; Taasan, Shlomo

    1995-01-01

    A new method for the acceleration of linear and nonlinear time dependent calculations is presented. It is based on the Large Discretization Step (LDS) approximation, defined in this work, which employs an extended system of low accuracy schemes to approximate a high accuracy discrete approximation to a time dependent differential operator. Error bounds on such approximations are derived. These approximations are efficiently implemented in the LDS methods for linear and nonlinear hyperbolic equations, presented here. In these algorithms the high and low accuracy schemes are interpreted as the same discretization of a time dependent operator on fine and coarse grids, respectively. Thus, a system of correction terms and corresponding equations are derived and solved on the coarse grid to yield the fine grid accuracy. These terms are initialized by visiting the fine grid once in many coarse grid time steps. The resulting methods are very general, simple to implement and may be used to accelerate many existing time marching schemes.

  16. Growth performance, haematology and cost benefit of growing rabbits reared on different feed access times and restriction durations

    Directory of Open Access Journals (Sweden)

    Obasa, O.A

    2016-06-01

    Full Text Available Sixty growing rabbits of mixed breeds and sexes were used for 10 wk in a 4 x 3 factorial experimental design to test for the effect of different feed access times (2, 4, 6 and 24 h and different restriction durations (2, 4 and 6 wk on the performance, haematological parameters and cost benefits of growing rabbits. Data obtained were subject to a 2�way analysis of variance. Results showed significantly higher (p0.05 across the feed access time and restriction duration. White blood cell was higher in growing rabbits on 2-h feed access time for 6-wk duration of restriction while all other parameters measured for haematology were not significantly affected by the feed access time and restriction duration. Total cost of feed consumed was highest in growing rabbits maintained on 24-h feed access time. Cost of feed per kg weight gain was not significantly influenced across the feed access times and the restriction durations. It was concluded that for a reduced cost of feeding without an adverse effect on the performance and haematological profile, growing rabbits should be raised on not less than 4-h feed access time for 2-wk restriction duration.

  17. Rapid expansion method (REM) for time‐stepping in reverse time migration (RTM)

    KAUST Repository

    Pestana, Reynam C.; Stoffa, Paul L.

    2009-01-01

    an analytical approximation for the Bessel function where we assume that the time step is sufficiently small. From this derivation we find that if we consider only the first two Chebyshev polynomials terms in the rapid expansion method we can obtain the second

  18. Displacement in the parameter space versus spurious solution of discretization with large time step

    International Nuclear Information System (INIS)

    Mendes, Eduardo; Letellier, Christophe

    2004-01-01

    In order to investigate a possible correspondence between differential and difference equations, it is important to possess discretization of ordinary differential equations. It is well known that when differential equations are discretized, the solution thus obtained depends on the time step used. In the majority of cases, such a solution is considered spurious when it does not resemble the expected solution of the differential equation. This often happens when the time step taken into consideration is too large. In this work, we show that, even for quite large time steps, some solutions which do not correspond to the expected ones are still topologically equivalent to solutions of the original continuous system if a displacement in the parameter space is considered. To reduce such a displacement, a judicious choice of the discretization scheme should be made. To this end, a recent discretization scheme, based on the Lie expansion of the original differential equations, proposed by Monaco and Normand-Cyrot will be analysed. Such a scheme will be shown to be sufficient for providing an adequate discretization for quite large time steps compared to the pseudo-period of the underlying dynamics

  19. Enforcing the Courant-Friedrichs-Lewy condition in explicitly conservative local time stepping schemes

    Science.gov (United States)

    Gnedin, Nickolay Y.; Semenov, Vadim A.; Kravtsov, Andrey V.

    2018-04-01

    An optimally efficient explicit numerical scheme for solving fluid dynamics equations, or any other parabolic or hyperbolic system of partial differential equations, should allow local regions to advance in time with their own, locally constrained time steps. However, such a scheme can result in violation of the Courant-Friedrichs-Lewy (CFL) condition, which is manifestly non-local. Although the violations can be considered to be "weak" in a certain sense and the corresponding numerical solution may be stable, such calculation does not guarantee the correct propagation speed for arbitrary waves. We use an experimental fluid dynamics code that allows cubic "patches" of grid cells to step with independent, locally constrained time steps to demonstrate how the CFL condition can be enforced by imposing a constraint on the time steps of neighboring patches. We perform several numerical tests that illustrate errors introduced in the numerical solutions by weak CFL condition violations and show how strict enforcement of the CFL condition eliminates these errors. In all our tests the strict enforcement of the CFL condition does not impose a significant performance penalty.

  20. Elderly fallers enhance dynamic stability through anticipatory postural adjustments during a choice stepping reaction time

    Directory of Open Access Journals (Sweden)

    Romain Tisserand

    2016-11-01

    Full Text Available In the case of disequilibrium, the capacity to step quickly is critical to avoid falling for elderly. This capacity can be simply assessed through the choice stepping reaction time test (CSRT, where elderly fallers (F take longer to step than elderly non-fallers (NF. However, reasons why elderly F elongate their stepping time remain unclear. The purpose of this study is to assess the characteristics of anticipated postural adjustments (APA that elderly F develop in a stepping context and their consequences on the dynamic stability. 44 community-dwelling elderly subjects (20 F and 22 NF performed a CSRT where kinematics and ground reaction forces were collected. Variables were analyzed using two-way repeated measures ANOVAs. Results for F compared to NF showed that stepping time is elongated, due to a longer APA phase. During APA, they seem to use two distinct balance strategies, depending on the axis: in the anteroposterior direction, we measured a smaller backward movement and slower peak velocity of the center of pressure (CoP; in the mediolateral direction, the CoP movement was similar in amplitude and peak velocity between groups but lasted longer. The biomechanical consequence of both strategies was an increased margin of stability (MoS at foot-off, in the respective direction. By elongating their APA, elderly F use a safer balance strategy that prioritizes dynamic stability conditions instead of the objective of the task. Such a choice in balance strategy probably comes from muscular limitations and/or a higher fear of falling and paradoxically indicates an increased risk of fall.

  1. Multi-Step Time Series Forecasting with an Ensemble of Varied Length Mixture Models.

    Science.gov (United States)

    Ouyang, Yicun; Yin, Hujun

    2018-05-01

    Many real-world problems require modeling and forecasting of time series, such as weather temperature, electricity demand, stock prices and foreign exchange (FX) rates. Often, the tasks involve predicting over a long-term period, e.g. several weeks or months. Most existing time series models are inheritably for one-step prediction, that is, predicting one time point ahead. Multi-step or long-term prediction is difficult and challenging due to the lack of information and uncertainty or error accumulation. The main existing approaches, iterative and independent, either use one-step model recursively or treat the multi-step task as an independent model. They generally perform poorly in practical applications. In this paper, as an extension of the self-organizing mixture autoregressive (AR) model, the varied length mixture (VLM) models are proposed to model and forecast time series over multi-steps. The key idea is to preserve the dependencies between the time points within the prediction horizon. Training data are segmented to various lengths corresponding to various forecasting horizons, and the VLM models are trained in a self-organizing fashion on these segments to capture these dependencies in its component AR models of various predicting horizons. The VLM models form a probabilistic mixture of these varied length models. A combination of short and long VLM models and an ensemble of them are proposed to further enhance the prediction performance. The effectiveness of the proposed methods and their marked improvements over the existing methods are demonstrated through a number of experiments on synthetic data, real-world FX rates and weather temperatures.

  2. Measuring border delay and crossing times at the US-Mexico border : part II. Step-by-step guidelines for implementing a radio frequency identification (RFID) system to measure border crossing and wait times.

    Science.gov (United States)

    2012-06-01

    The purpose of these step-by-step guidelines is to assist in planning, designing, and deploying a system that uses radio frequency identification (RFID) technology to measure the time needed for commercial vehicles to complete the northbound border c...

  3. Sleep restriction and degraded reaction-time performance in Figaro solo sailing races.

    Science.gov (United States)

    Hurdiel, Rémy; Van Dongen, Hans P A; Aron, Christophe; McCauley, Peter; Jacolot, Laure; Theunynck, Denis

    2014-01-01

    In solo offshore sailing races like those of the Solitaire du Figaro, sleep must be obtained in multiple short bouts to maintain competitive performance and safety. Little is known about the amount of sleep restriction experienced at sea and the effects that fatigue from sleep loss have on sailors' performance. Therefore, we assessed sleep in sailors of yachts in the Figaro 2 Beneteau class during races and compared response times on a serial simple reaction-time test before and after races. Twelve men (professional sailors) recorded their sleep and measured their response times during one of the three single-handed races of 150, 300 and 350 nautical miles (nominally 24-50 h in duration). Total estimated sleep duration at sea indicated considerable sleep insufficiency. Response times were slower after races than before. The results suggest that professional sailors incur severe sleep loss and demonstrate marked performance impairment when competing in one- to two-day solo sailing races. Competitive performance could be improved by actively managing sleep during solo offshore sailing races.

  4. Multi-step-prediction of chaotic time series based on co-evolutionary recurrent neural network

    International Nuclear Information System (INIS)

    Ma Qianli; Zheng Qilun; Peng Hong; Qin Jiangwei; Zhong Tanwei

    2008-01-01

    This paper proposes a co-evolutionary recurrent neural network (CERNN) for the multi-step-prediction of chaotic time series, it estimates the proper parameters of phase space reconstruction and optimizes the structure of recurrent neural networks by co-evolutionary strategy. The searching space was separated into two subspaces and the individuals are trained in a parallel computational procedure. It can dynamically combine the embedding method with the capability of recurrent neural network to incorporate past experience due to internal recurrence. The effectiveness of CERNN is evaluated by using three benchmark chaotic time series data sets: the Lorenz series, Mackey-Glass series and real-world sun spot series. The simulation results show that CERNN improves the performances of multi-step-prediction of chaotic time series

  5. Evaluating the impact of a novel restricted reimbursement policy for quinolone antibiotics: A time series analysis

    Directory of Open Access Journals (Sweden)

    Manns Braden

    2012-08-01

    Full Text Available Abstract Background Publicly-funded drug plans often use prior authorization policies to limit drug prescribing. To guide physician prescribing of a class of antibiotics with broad antimicrobial activity (quinolone antibiotics in accordance with new prescribing guidelines, Alberta’s provincial health ministry implemented a new mechanism for formulary restriction entitled the optional special authorization (OSA program. We conducted an observational study to determine the impact of this new formulary restriction policy on antimicrobial prescription rates as well as any clinical consequences. Methods Quinolone antibiotic use, and adherence with quinolone prescribing guidelines, was assessed before and after implementation of the OSA program in patients with common outpatient infections using an administrative data cohort and a chart review cohort, respectively. At the same time this policy was implemented to limit quinolone prescribing, two new quinolone antibiotics were added to the formulary. Using administrative data, we analysed a total of 397,534 unique index visits with regard to overall antibiotic utilization, and through chart review, we analysed 1681 charts of patients with infections of interest to determine the indications for quinolone usage. Results Using segmented regression models adjusting for age, sex and physician enrollment in the OSA program, there was no statistically significant change in the monthly rate of all quinolone use (−3.5 (95% CI −5.5, 1.4 prescriptions per 1000 index visits following implementation of the OSA program (p = 0.74. There was a significant level change in the rate of quinolone antibiotic use for urinary tract infection (−33.6 (95% CI: -23.8, -43.4 prescriptions and upper respiratory tract infection (−16.1 (95%CI: -11.6, -20.6 prescriptions per 1000 index visits. Among quinolone prescriptions identified on chart review, 42.5% and 58.5% were consistent with formulary guidelines before and

  6. Influence of timing and duration of feed restriction on growth and ...

    African Journals Online (AJOL)

    Unrestricted (R0) was the control where birds fed ad libitum. In R5, birds were restricted the 5th week; R56, 5th and 6th weeks; R67, 6th and 7th weeks, and R57, 5th and 7th weeks. However, all the feed-restricted birds fed ad libitum in the 8th week. Feed restriction involved feeding one-third feed intake of R0 birds starting ...

  7. A coupled weather generator - rainfall-runoff approach on hourly time steps for flood risk analysis

    Science.gov (United States)

    Winter, Benjamin; Schneeberger, Klaus; Dung Nguyen, Viet; Vorogushyn, Sergiy; Huttenlau, Matthias; Merz, Bruno; Stötter, Johann

    2017-04-01

    The evaluation of potential monetary damage of flooding is an essential part of flood risk management. One possibility to estimate the monetary risk is to analyze long time series of observed flood events and their corresponding damages. In reality, however, only few flood events are documented. This limitation can be overcome by the generation of a set of synthetic, physically and spatial plausible flood events and subsequently the estimation of the resulting monetary damages. In the present work, a set of synthetic flood events is generated by a continuous rainfall-runoff simulation in combination with a coupled weather generator and temporal disaggregation procedure for the study area of Vorarlberg (Austria). Most flood risk studies focus on daily time steps, however, the mesoscale alpine study area is characterized by short concentration times, leading to large differences between daily mean and daily maximum discharge. Accordingly, an hourly time step is needed for the simulations. The hourly metrological input for the rainfall-runoff model is generated in a two-step approach. A synthetic daily dataset is generated by a multivariate and multisite weather generator and subsequently disaggregated to hourly time steps with a k-Nearest-Neighbor model. Following the event generation procedure, the negative consequences of flooding are analyzed. The corresponding flood damage for each synthetic event is estimated by combining the synthetic discharge at representative points of the river network with a loss probability relation for each community in the study area. The loss probability relation is based on exposure and susceptibility analyses on a single object basis (residential buildings) for certain return periods. For these impact analyses official inundation maps of the study area are used. Finally, by analyzing the total event time series of damages, the expected annual damage or losses associated with a certain probability of occurrence can be estimated for

  8. Multi-Time Step Service Restoration for Advanced Distribution Systems and Microgrids

    International Nuclear Information System (INIS)

    Chen, Bo; Chen, Chen; Wang, Jianhui; Butler-Purry, Karen L.

    2017-01-01

    Modern power systems are facing increased risk of disasters that can cause extended outages. The presence of remote control switches (RCSs), distributed generators (DGs), and energy storage systems (ESS) provides both challenges and opportunities for developing post-fault service restoration methodologies. Inter-temporal constraints of DGs, ESS, and loads under cold load pickup (CLPU) conditions impose extra complexity on problem formulation and solution. In this paper, a multi-time step service restoration methodology is proposed to optimally generate a sequence of control actions for controllable switches, ESSs, and dispatchable DGs to assist the system operator with decision making. The restoration sequence is determined to minimize the unserved customers by energizing the system step by step without violating operational constraints at each time step. The proposed methodology is formulated as a mixed-integer linear programming (MILP) model and can adapt to various operation conditions. Furthermore, the proposed method is validated through several case studies that are performed on modified IEEE 13-node and IEEE 123-node test feeders.

  9. Development of a real time activity monitoring Android application utilizing SmartStep.

    Science.gov (United States)

    Hegde, Nagaraj; Melanson, Edward; Sazonov, Edward

    2016-08-01

    Footwear based activity monitoring systems are becoming popular in academic research as well as consumer industry segments. In our previous work, we had presented developmental aspects of an insole based activity and gait monitoring system-SmartStep, which is a socially acceptable, fully wireless and versatile insole. The present work describes the development of an Android application that captures the SmartStep data wirelessly over Bluetooth Low energy (BLE), computes features on the received data, runs activity classification algorithms and provides real time feedback. The development of activity classification methods was based on the the data from a human study involving 4 participants. Participants were asked to perform activities of sitting, standing, walking, and cycling while they wore SmartStep insole system. Multinomial Logistic Discrimination (MLD) was utilized in the development of machine learning model for activity prediction. The resulting classification model was implemented in an Android Smartphone. The Android application was benchmarked for power consumption and CPU loading. Leave one out cross validation resulted in average accuracy of 96.9% during model training phase. The Android application for real time activity classification was tested on a human subject wearing SmartStep resulting in testing accuracy of 95.4%.

  10. Two-Step Time of Arrival Estimation for Pulse-Based Ultra-Wideband Systems

    Directory of Open Access Journals (Sweden)

    H. Vincent Poor

    2008-05-01

    Full Text Available In cooperative localization systems, wireless nodes need to exchange accurate position-related information such as time-of-arrival (TOA and angle-of-arrival (AOA, in order to obtain accurate location information. One alternative for providing accurate position-related information is to use ultra-wideband (UWB signals. The high time resolution of UWB signals presents a potential for very accurate positioning based on TOA estimation. However, it is challenging to realize very accurate positioning systems in practical scenarios, due to both complexity/cost constraints and adverse channel conditions such as multipath propagation. In this paper, a two-step TOA estimation algorithm is proposed for UWB systems in order to provide accurate TOA estimation under practical constraints. In order to speed up the estimation process, the first step estimates a coarse TOA of the received signal based on received signal energy. Then, in the second step, the arrival time of the first signal path is estimated by considering a hypothesis testing approach. The proposed scheme uses low-rate correlation outputs and is able to perform accurate TOA estimation in reasonable time intervals. The simulation results are presented to analyze the performance of the estimator.

  11. Steps of Supercritical Fluid Extraction of Natural Products and Their Characteristic Times

    OpenAIRE

    Sovová, H. (Helena)

    2012-01-01

    Kinetics of supercritical fluid extraction (SFE) from plants is variable due to different micro-structure of plants and their parts, different properties of extracted substances and solvents, and different flow patterns in the extractor. Variety of published mathematical models for SFE of natural products corresponds to this diversification. This study presents simplified equations of extraction curves in terms of characteristic times of four single extraction steps: internal diffusion, exter...

  12. Multiple Time-Step Dual-Hamiltonian Hybrid Molecular Dynamics - Monte Carlo Canonical Propagation Algorithm.

    Science.gov (United States)

    Chen, Yunjie; Kale, Seyit; Weare, Jonathan; Dinner, Aaron R; Roux, Benoît

    2016-04-12

    A multiple time-step integrator based on a dual Hamiltonian and a hybrid method combining molecular dynamics (MD) and Monte Carlo (MC) is proposed to sample systems in the canonical ensemble. The Dual Hamiltonian Multiple Time-Step (DHMTS) algorithm is based on two similar Hamiltonians: a computationally expensive one that serves as a reference and a computationally inexpensive one to which the workload is shifted. The central assumption is that the difference between the two Hamiltonians is slowly varying. Earlier work has shown that such dual Hamiltonian multiple time-step schemes effectively precondition nonlinear differential equations for dynamics by reformulating them into a recursive root finding problem that can be solved by propagating a correction term through an internal loop, analogous to RESPA. Of special interest in the present context, a hybrid MD-MC version of the DHMTS algorithm is introduced to enforce detailed balance via a Metropolis acceptance criterion and ensure consistency with the Boltzmann distribution. The Metropolis criterion suppresses the discretization errors normally associated with the propagation according to the computationally inexpensive Hamiltonian, treating the discretization error as an external work. Illustrative tests are carried out to demonstrate the effectiveness of the method.

  13. Real-time, single-step bioassay using nanoplasmonic resonator with ultra-high sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiang; Ellman, Jonathan A; Chen, Fanqing Frank; Su, Kai-Hang; Wei, Qi-Huo; Sun, Cheng

    2014-04-01

    A nanoplasmonic resonator (NPR) comprising a metallic nanodisk with alternating shielding layer(s), having a tagged biomolecule conjugated or tethered to the surface of the nanoplasmonic resonator for highly sensitive measurement of enzymatic activity. NPRs enhance Raman signals in a highly reproducible manner, enabling fast detection of protease and enzyme activity, such as Prostate Specific Antigen (paPSA), in real-time, at picomolar sensitivity levels. Experiments on extracellular fluid (ECF) from paPSA-positive cells demonstrate specific detection in a complex bio-fluid background in real-time single-step detection in very small sample volumes.

  14. Stress within a Restricted Time Window Selectively Affects the Persistence of Long-Term Memory

    Science.gov (United States)

    Fang, Qin; Chai, Ning; Zhao, Li-Yan; Xue, Yan-Xue; Luo, Yi-Xiao; Jian, Min; Han, Ying; Shi, Hai-Shui; Lu, Lin; Wu, Ping; Wang, Ji-Shi

    2013-01-01

    The effects of stress on emotional memory are distinct and depend on the stages of memory. Memory undergoes consolidation and reconsolidation after acquisition and retrieval, respectively. Stress facilitates the consolidation but disrupts the reconsolidation of emotional memory. Previous research on the effects of stress on memory have focused on long-term memory (LTM) formation (tested 24 h later), but the effects of stress on the persistence of LTM (tested at least 1 week later) are unclear. Recent findings indicated that the persistence of LTM requires late-phase protein synthesis in the dorsal hippocampus. The present study investigated the effect of stress (i.e., cold water stress) during the late phase after the acquisition and retrieval of contextual fear memory in rats. We found that stress and corticosterone administration during the late phase (12 h) after acquisition, referred to as late consolidation, selectively enhanced the persistence of LTM, whereas stress during the late phase (12 h) after retrieval, referred to as late reconsolidation, selectively disrupted the restabilized persistence of LTM. Moreover, the effects of stress on the persistence of LTM were blocked by the corticosterone synthesis inhibitor metyrapone, which was administered before stress, suggesting that the glucocorticoid system is involved in the effects of stress on the persistence of LTM. We conclude that stress within a restricted time window after acquisition or retrieval selectively affects the persistence of LTM and depends on the glucocorticoid system. PMID:23544051

  15. Social-Cognitive Predictors of Low-Income Parents' Restriction of Screen Time among Preschool-Aged Children

    Science.gov (United States)

    Lampard, Amy M.; Jurkowski, Janine M.; Davison, Kirsten K.

    2013-01-01

    Parents' rules regarding child television, DVD, video game, and computer use (screen time) have been associated with lower screen use in children. This study aimed to identify modifiable correlates of this behavior by examining social-cognitive predictors of parents' restriction of child screen time. Low-income parents ("N" = 147) of…

  16. Combined Effects of Numerical Method Type and Time Step on Water Stressed Actual Crop ET

    Directory of Open Access Journals (Sweden)

    B. Ghahraman

    2016-02-01

    Full Text Available Introduction: Actual crop evapotranspiration (Eta is important in hydrologic modeling and irrigation water management issues. Actual ET depends on an estimation of a water stress index and average soil water at crop root zone, and so depends on a chosen numerical method and adapted time step. During periods with no rainfall and/or irrigation, actual ET can be computed analytically or by using different numerical methods. Overal, there are many factors that influence actual evapotranspiration. These factors are crop potential evapotranspiration, available root zone water content, time step, crop sensitivity, and soil. In this paper different numerical methods are compared for different soil textures and different crops sensitivities. Materials and Methods: During a specific time step with no rainfall or irrigation, change in soil water content would be equal to evapotranspiration, ET. In this approach, however, deep percolation is generally ignored due to deep water table and negligible unsaturated hydraulic conductivity below rooting depth. This differential equation may be solved analytically or numerically considering different algorithms. We adapted four different numerical methods, as explicit, implicit, and modified Euler, midpoint method, and 3-rd order Heun method to approximate the differential equation. Three general soil types of sand, silt, and clay, and three different crop types of sensitive, moderate, and resistant under Nishaboor plain were used. Standard soil fraction depletion (corresponding to ETc=5 mm.d-1, pstd, below which crop faces water stress is adopted for crop sensitivity. Three values for pstd were considered in this study to cover the common crops in the area, including winter wheat and barley, cotton, alfalfa, sugar beet, saffron, among the others. Based on this parameter, three classes for crop sensitivity was considered, sensitive crops with pstd=0.2, moderate crops with pstd=0.5, and resistive crops with pstd=0

  17. Scalable explicit implementation of anisotropic diffusion with Runge-Kutta-Legendre super-time stepping

    Science.gov (United States)

    Vaidya, Bhargav; Prasad, Deovrat; Mignone, Andrea; Sharma, Prateek; Rickler, Luca

    2017-12-01

    An important ingredient in numerical modelling of high temperature magnetized astrophysical plasmas is the anisotropic transport of heat along magnetic field lines from higher to lower temperatures. Magnetohydrodynamics typically involves solving the hyperbolic set of conservation equations along with the induction equation. Incorporating anisotropic thermal conduction requires to also treat parabolic terms arising from the diffusion operator. An explicit treatment of parabolic terms will considerably reduce the simulation time step due to its dependence on the square of the grid resolution (Δx) for stability. Although an implicit scheme relaxes the constraint on stability, it is difficult to distribute efficiently on a parallel architecture. Treating parabolic terms with accelerated super-time-stepping (STS) methods has been discussed in literature, but these methods suffer from poor accuracy (first order in time) and also have difficult-to-choose tuneable stability parameters. In this work, we highlight a second-order (in time) Runge-Kutta-Legendre (RKL) scheme (first described by Meyer, Balsara & Aslam 2012) that is robust, fast and accurate in treating parabolic terms alongside the hyperbolic conversation laws. We demonstrate its superiority over the first-order STS schemes with standard tests and astrophysical applications. We also show that explicit conduction is particularly robust in handling saturated thermal conduction. Parallel scaling of explicit conduction using RKL scheme is demonstrated up to more than 104 processors.

  18. Rapid expansion method (REM) for time‐stepping in reverse time migration (RTM)

    KAUST Repository

    Pestana, Reynam C.

    2009-01-01

    We show that the wave equation solution using a conventional finite‐difference scheme, derived commonly by the Taylor series approach, can be derived directly from the rapid expansion method (REM). After some mathematical manipulation we consider an analytical approximation for the Bessel function where we assume that the time step is sufficiently small. From this derivation we find that if we consider only the first two Chebyshev polynomials terms in the rapid expansion method we can obtain the second order time finite‐difference scheme that is frequently used in more conventional finite‐difference implementations. We then show that if we use more terms from the REM we can obtain a more accurate time integration of the wave field. Consequently, we have demonstrated that the REM is more accurate than the usual finite‐difference schemes and it provides a wave equation solution which allows us to march in large time steps without numerical dispersion and is numerically stable. We illustrate the method with post and pre stack migration results.

  19. The subtle danger of symmetry restrictions in time series regressions, with application to fertility models.

    Science.gov (United States)

    Haynes, S E

    1983-10-01

    It is widely known that linear restrictions involve bias. What is not known is that some linear restrictions are especially dangerous for hypothesis testing. For some, the expected value of the restricted coefficient does not lie between (among) the true unconstrained coefficients, which implies that the estimate is not a simple average of these coefficients. In this paper, the danger is examined regarding the additive linear restriction almost universally imposed in statistical research--the restriction of symmetry. Symmetry implies that the response of the dependent variable to a unit decrease in an expanatory variable is identical, but of opposite sign, to the response to a unit increase. The 1st section of the paper demonstrates theoretically that a coefficient restricted by symmetry (unlike coefficients embodying other additive restrictions) is not a simple average of the unconstrained coefficients because the relevant interacted variables are inversly correlated by definition. The next section shows that, under the restriction of symmetry, fertility in Finland from 1885-1925 appears to respond in a prolonged manner to infant mortality (significant and positive with a lag of 4-6 years), suggesting a response to expected deaths. However, unscontrained estimates indicate that this finding is spurious. When the restriction is relaxed, the dominant response is rapid (significant and positive with a lag of 1-2 years) and stronger for declines in mortality, supporting an aymmetric response to actual deaths. For 2 reasons, the danger of the symmetry restriction may be especially pervasive. 1st, unlike most other linear constraints, symmetry is passively imposed merely by ignoring the possibility of asymmetry. 2nd, modles in a wide range of fields--including macroeconomics (e.g., demand for money, consumption, and investment models, and the Phillips curve), international economics (e.g., intervention models of central banks), and labor economics (e.g., sticky wage

  20. Time-dependent restricted-active-space self-consistent-field theory for bosonic many-body systems

    International Nuclear Information System (INIS)

    Lévêque, Camille; Madsen, Lars Bojer

    2017-01-01

    We develop an ab initio time-dependent wavefunction based theory for the description of a many-body system of cold interacting bosons. Like the multi-configurational time-dependent Hartree method for bosons (MCTDHB), the theory is based on a configurational interaction Ansatz for the many-body wavefunction with time-dependent self-consistent-field orbitals. The theory generalizes the MCTDHB method by incorporating restrictions on the active space of the orbital excitations. The restrictions are specified based on the physical situation at hand. The equations of motion of this time-dependent restricted-active-space self-consistent-field (TD-RASSCF) theory are derived. The similarity between the formal development of the theory for bosons and fermions is discussed. The restrictions on the active space allow the theory to be evaluated under conditions where other wavefunction based methods due to exponential scaling in the numerical effort cannot, and to clearly identify the excitations that are important for an accurate description, significantly beyond the mean-field approach. For ground state calculations we find it to be important to allow a few particles to have the freedom to move in many orbitals, an insight facilitated by the flexibility of the restricted-active-space Ansatz . Moreover, we find that a high accuracy can be obtained by including only even excitations in the many-body self-consistent-field wavefunction. Time-dependent simulations of harmonically trapped bosons subject to a quenching of their noncontact interaction, show failure of the mean-field Gross-Pitaevskii approach within a fraction of a harmonic oscillation period. The TD-RASSCF theory remains accurate at much reduced computational cost compared to the MCTDHB method. Exploring the effect of changes of the restricted-active-space allows us to identify that even self-consistent-field excitations are mainly responsible for the accuracy of the method. (paper)

  1. Intake flow and time step analysis in the modeling of a direct injection Diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Zancanaro Junior, Flavio V.; Vielmo, Horacio A. [Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Mechanical Engineering Dept.], E-mails: zancanaro@mecanica.ufrgs.br, vielmoh@mecanica.ufrgs.br

    2010-07-01

    This paper discusses the effects of the time step on turbulence flow structure in the intake and in-cylinder systems of a Diesel engine during the intake process, under the motored condition. The three-dimensional modeling of a reciprocating engine geometry comprising a bowl-in-piston combustion chamber, intake port of shallow ramp helical type and exhaust port of conventional type. The equations are numerically solved, including a transient analysis, valves and piston movements, for engine speed of 1500 rpm, using a commercial Finite Volumes CFD code. A parallel computation is employed. For the purpose of examining the in-cylinder turbulence characteristics two parameters are observed: the discharge coefficient and swirl ratio. This two parameters quantify the fluid flow characteristics inside cylinder in the intake stroke, therefore, it is very important their study and understanding. Additionally, the evolution of the discharge coefficient and swirl ratio, along crank angle, are correlated and compared, with the objective of clarifying the physical mechanisms. Regarding the turbulence, computations are performed with the Eddy Viscosity Model k-u SST, in its Low-Reynolds approaches, with standard near wall treatment. The system of partial differential equations to be solved consists of the Reynolds-averaged compressible Navier-Stokes equations with the constitutive relations for an ideal gas, and using a segregated solution algorithm. The enthalpy equation is also solved. A moving hexahedral trimmed mesh independence study is presented. In the same way many convergence tests are performed, and a secure criterion established. The results of the pressure fields are shown in relation to vertical plane that passes through the valves. Areas of low pressure can be seen in the valve curtain region, due to strong jet flows. Also, it is possible to note divergences between the time steps, mainly for the smaller time step. (author)

  2. Smart Wireless Power Transfer Operated by Time-Modulated Arrays via a Two-Step Procedure

    Directory of Open Access Journals (Sweden)

    Diego Masotti

    2015-01-01

    Full Text Available The paper introduces a novel method for agile and precise wireless power transmission operated by a time-modulated array. The unique, almost real-time reconfiguration capability of these arrays is fully exploited by a two-step procedure: first, a two-element time-modulated subarray is used for localization of tagged sensors to be energized; the entire 16-element TMA then provides the power to the detected tags, by exploiting the fundamental and first-sideband harmonic radiation. An investigation on the best array architecture is carried out, showing the importance of the adopted nonlinear/full-wave computer-aided-design platform. Very promising simulated energy transfer performance of the entire nonlinear radiating system is demonstrated.

  3. Associations of office workers' objectively assessed occupational sitting, standing and stepping time with musculoskeletal symptoms.

    Science.gov (United States)

    Coenen, Pieter; Healy, Genevieve N; Winkler, Elisabeth A H; Dunstan, David W; Owen, Neville; Moodie, Marj; LaMontagne, Anthony D; Eakin, Elizabeth A; O'Sullivan, Peter B; Straker, Leon M

    2018-04-22

    We examined the association of musculoskeletal symptoms (MSS) with workplace sitting, standing and stepping time, as well as sitting and standing time accumulation (i.e. usual bout duration of these activities), measured objectively with the activPAL3 monitor. Using baseline data from the Stand Up Victoria trial (216 office workers, 14 workplaces), cross-sectional associations of occupational activities with self-reported MSS (low-back, upper and lower extremity symptoms in the last three months) were examined using probit regression, correcting for clustering and adjusting for confounders. Sitting bout duration was significantly (p < 0.05) associated, non-linearly, with MSS, such that those in the middle tertile displayed the highest prevalence of upper extremity symptoms. Other associations were non-significant but sometimes involved large differences in symptom prevalence (e.g. 38%) by activity. Though causation is unclear, these non-linear associations suggest that sitting and its alternatives (i.e. standing and stepping) interact with MSS and this should be considered when designing safe work systems. Practitioner summary: We studied associations of objectively assessed occupational activities with musculoskeletal symptoms in office workers. Workers who accumulated longer sitting bouts reported fewer upper extremity symptoms. Total activity duration was not significantly associated with musculoskeletal symptoms. We underline the importance of considering total volumes and patterns of activity time in musculoskeletal research.

  4. A multi-time-step noise reduction method for measuring velocity statistics from particle tracking velocimetry

    Science.gov (United States)

    Machicoane, Nathanaël; López-Caballero, Miguel; Bourgoin, Mickael; Aliseda, Alberto; Volk, Romain

    2017-10-01

    We present a method to improve the accuracy of velocity measurements for fluid flow or particles immersed in it, based on a multi-time-step approach that allows for cancellation of noise in the velocity measurements. Improved velocity statistics, a critical element in turbulent flow measurements, can be computed from the combination of the velocity moments computed using standard particle tracking velocimetry (PTV) or particle image velocimetry (PIV) techniques for data sets that have been collected over different values of time intervals between images. This method produces Eulerian velocity fields and Lagrangian velocity statistics with much lower noise levels compared to standard PIV or PTV measurements, without the need of filtering and/or windowing. Particle displacement between two frames is computed for multiple different time-step values between frames in a canonical experiment of homogeneous isotropic turbulence. The second order velocity structure function of the flow is computed with the new method and compared to results from traditional measurement techniques in the literature. Increased accuracy is also demonstrated by comparing the dissipation rate of turbulent kinetic energy measured from this function against previously validated measurements.

  5. A one-step, real-time PCR assay for rapid detection of rhinovirus.

    Science.gov (United States)

    Do, Duc H; Laus, Stella; Leber, Amy; Marcon, Mario J; Jordan, Jeanne A; Martin, Judith M; Wadowsky, Robert M

    2010-01-01

    One-step, real-time PCR assays for rhinovirus have been developed for a limited number of PCR amplification platforms and chemistries, and some exhibit cross-reactivity with genetically similar enteroviruses. We developed a one-step, real-time PCR assay for rhinovirus by using a sequence detection system (Applied Biosystems; Foster City, CA). The primers were designed to amplify a 120-base target in the noncoding region of picornavirus RNA, and a TaqMan (Applied Biosystems) degenerate probe was designed for the specific detection of rhinovirus amplicons. The PCR assay had no cross-reactivity with a panel of 76 nontarget nucleic acids, which included RNAs from 43 enterovirus strains. Excellent lower limits of detection relative to viral culture were observed for the PCR assay by using 38 of 40 rhinovirus reference strains representing different serotypes, which could reproducibly detect rhinovirus serotype 2 in viral transport medium containing 10 to 10,000 TCID(50) (50% tissue culture infectious dose endpoint) units/ml of the virus. However, for rhinovirus serotypes 59 and 69, the PCR assay was less sensitive than culture. Testing of 48 clinical specimens from children with cold-like illnesses for rhinovirus by the PCR and culture assays yielded detection rates of 16.7% and 6.3%, respectively. For a batch of 10 specimens, the entire assay was completed in 4.5 hours. This real-time PCR assay enables detection of many rhinovirus serotypes with the Applied Biosystems reagent-instrument platform.

  6. Imaginary Time Step Method to Solve the Dirac Equation with Nonlocal Potential

    International Nuclear Information System (INIS)

    Zhang Ying; Liang Haozhao; Meng Jie

    2009-01-01

    The imaginary time step (ITS) method is applied to solve the Dirac equation with nonlocal potentials in coordinate space. Taking the nucleus 12 C as an example, even with nonlocal potentials, the direct ITS evolution for the Dirac equation still meets the disaster of the Dirac sea. However, following the recipe in our former investigation, the disaster can be avoided by the ITS evolution for the corresponding Schroedinger-like equation without localization, which gives the convergent results exactly the same with those obtained iteratively by the shooting method with localized effective potentials.

  7. Rigid Body Sampling and Individual Time Stepping for Rigid-Fluid Coupling of Fluid Simulation

    Directory of Open Access Journals (Sweden)

    Xiaokun Wang

    2017-01-01

    Full Text Available In this paper, we propose an efficient and simple rigid-fluid coupling scheme with scientific programming algorithms for particle-based fluid simulation and three-dimensional visualization. Our approach samples the surface of rigid bodies with boundary particles that interact with fluids. It contains two procedures, that is, surface sampling and sampling relaxation, which insures uniform distribution of particles with less iterations. Furthermore, we present a rigid-fluid coupling scheme integrating individual time stepping to rigid-fluid coupling, which gains an obvious speedup compared to previous method. The experimental results demonstrate the effectiveness of our approach.

  8. The enhancement of time-stepping procedures in SYVAC A/C

    International Nuclear Information System (INIS)

    Broyd, T.W.

    1986-01-01

    This report summarises the work carried out an SYVAC A/C between February and May 1985 aimed at improving the way in which time-stepping procedures are handled. The majority of the work was concerned with three types of problem, viz: i) Long vault release, short geosphere response ii) Short vault release, long geosphere response iii) Short vault release, short geosphere response The report contains details of changes to the logic and structure of SYVAC A/C, as well as the results of code implementation tests. It has been written primarily for members of the UK SYVAC development team, and should not be used or referred to in isolation. (author)

  9. Time ordering of two-step processes in energetic ion-atom collisions: Basic formalism

    International Nuclear Information System (INIS)

    Stolterfoht, N.

    1993-01-01

    The semiclassical approximation is applied in second order to describe time ordering of two-step processes in energetic ion-atom collisions. Emphasis is given to the conditions for interferences between first- and second-order terms. In systems with two active electrons, time ordering gives rise to a pair of associated paths involving a second-order process and its time-inverted process. Combining these paths within the independent-particle frozen orbital model, time ordering is lost. It is shown that the loss of time ordering modifies the second-order amplitude so that its ability to interfere with the first-order amplitude is essentially reduced. Time ordering and the capability for interference is regained, as one path is blocked by means of the Pauli exclusion principle. The time-ordering formalism is prepared for papers dealing with collision experiments of single excitation [Stolterfoht et al., following paper, Phys. Rev. A 48, 2986 (1993)] and double excitation [Stolterfoht et al. (unpublished)

  10. Stability of the high-order finite elements for acoustic or elastic wave propagation with high-order time stepping

    KAUST Repository

    De Basabe, Joná s D.; Sen, Mrinal K.

    2010-01-01

    popular in the recent past. We consider the Lax-Wendroff method (LWM) for time stepping and show that it allows for a larger time step than the classical leap-frog finite difference method, with higher-order accuracy. In particular the fourth-order LWM

  11. Sharp Penalty Term and Time Step Bounds for the Interior Penalty Discontinuous Galerkin Method for Linear Hyperbolic Problems

    NARCIS (Netherlands)

    Geevers, Sjoerd; van der Vegt, J.J.W.

    2017-01-01

    We present sharp and sucient bounds for the interior penalty term and time step size to ensure stability of the symmetric interior penalty discontinuous Galerkin (SIPDG) method combined with an explicit time-stepping scheme. These conditions hold for generic meshes, including unstructured

  12. Discrete maximal regularity of time-stepping schemes for fractional evolution equations.

    Science.gov (United States)

    Jin, Bangti; Li, Buyang; Zhou, Zhi

    2018-01-01

    In this work, we establish the maximal [Formula: see text]-regularity for several time stepping schemes for a fractional evolution model, which involves a fractional derivative of order [Formula: see text], [Formula: see text], in time. These schemes include convolution quadratures generated by backward Euler method and second-order backward difference formula, the L1 scheme, explicit Euler method and a fractional variant of the Crank-Nicolson method. The main tools for the analysis include operator-valued Fourier multiplier theorem due to Weis (Math Ann 319:735-758, 2001. doi:10.1007/PL00004457) and its discrete analogue due to Blunck (Stud Math 146:157-176, 2001. doi:10.4064/sm146-2-3). These results generalize the corresponding results for parabolic problems.

  13. Intraindividual Stepping Reaction Time Variability Predicts Falls in Older Adults With Mild Cognitive Impairment.

    Science.gov (United States)

    Bunce, David; Haynes, Becky I; Lord, Stephen R; Gschwind, Yves J; Kochan, Nicole A; Reppermund, Simone; Brodaty, Henry; Sachdev, Perminder S; Delbaere, Kim

    2017-06-01

    Reaction time measures have considerable potential to aid neuropsychological assessment in a variety of health care settings. One such measure, the intraindividual reaction time variability (IIV), is of particular interest as it is thought to reflect neurobiological disturbance. IIV is associated with a variety of age-related neurological disorders, as well as gait impairment and future falls in older adults. However, although persons diagnosed with Mild Cognitive Impairment (MCI) are at high risk of falling, the association between IIV and prospective falls is unknown. We conducted a longitudinal cohort study in cognitively intact (n = 271) and MCI (n = 154) community-dwelling adults aged 70-90 years. IIV was assessed through a variety of measures including simple and choice hand reaction time and choice stepping reaction time tasks (CSRT), the latter administered as a single task and also with a secondary working memory task. Logistic regression did not show an association between IIV on the hand-held tasks and falls. Greater IIV in both CSRT tasks, however, did significantly increase the risk of future falls. This effect was specific to the MCI group, with a stronger effect in persons exhibiting gait, posture, or physiological impairment. The findings suggest that increased stepping IIV may indicate compromised neural circuitry involved in executive function, gait, and posture in persons with MCI increasing their risk of falling. IIV measures have potential to assess neurobiological disturbance underlying physical and cognitive dysfunction in old age, and aid fall risk assessment and routine care in community and health care settings. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Restricting access time at pasture and time of grazing allocation for Holstein dairy cows: Ingestive behaviour, dry matter intake and milk production

    NARCIS (Netherlands)

    Mattiauda, D.A.; Tamminga, S.; Gibb, M.J.; Soca, P.; Bentancur, O.; Chilibroste, P.

    2013-01-01

    The objective of this study was to assess the effects of restricting access time to pasture and time of grazing allocation on grazing behaviour, daily dry matter intake (DMI), rumen fermentation, milk production and composition in dairy cows. Twenty-one autumn-calving Holstein cows were assigned to

  15. Effect of restricting silage feeding prepartum on time of calving, dystocia and stillbirth in Holstein-Friesian cows

    Directory of Open Access Journals (Sweden)

    Gleeson David E

    2007-11-01

    Full Text Available Abstract A study was carried out to investigate the effect of restricting silage feeding on time of calving and calving performance in Holstein-Friesian cows. In the treatment group (n = 1,248 cows, 12 herds silage feeding commenced in the evening (17:00 to 20:00 h, after a period of restricted access (2 to 10 h while in the control group ad-libitum access to silage was provided over the 24 h period (n = 1,193 cows, 12 herds. Daytime and nighttime calvings were defined as calvings occurring between the hours of 06:30 and 00:29 and between 00:30 and 06:29, respectively. Restricting access to silage resulted in less calvings at night compared to cows with ad-libitum access to silage (18 vs 22%, P

  16. Development of real time diagnostics and feedback algorithms for JET in view of the next step

    International Nuclear Information System (INIS)

    Murari, A.; Felton, R.; Zabeo, L.; Piccolo, F.; Sartori, F.; Murari, A.; Barana, O.; Albanese, R.; Joffrin, E.; Mazon, D.; Laborde, L.; Moreau, D.; Arena, P.; Bruno, M.; Ambrosino, G.; Ariola, M.; Crisanti, F.; Luna, E. de la; Sanchez, J.

    2004-01-01

    Real time control of many plasma parameters will be an essential aspect in the development of reliable high performance operation of Next Step Tokamaks. The main prerequisites for any feedback scheme are the precise real-time determination of the quantities to be controlled, requiring top quality and highly reliable diagnostics, and the availability of robust control algorithms. A new set of real time diagnostics was recently implemented on JET to prove the feasibility of determining, with high accuracy and time resolution, the most important plasma quantities. With regard to feedback algorithms, new model-based controllers were developed to allow a more robust control of several plasma parameters. Both diagnostics and algorithms were successfully used in several experiments, ranging from H-mode plasmas to configuration with internal transport barriers. Since elaboration of computationally heavy measurements is often required, significant attention was devoted to non-algorithmic methods like Digital or Cellular Neural/Nonlinear Networks. The real time hardware and software adopted architectures are also described with particular attention to their relevance to ITER. (authors)

  17. Development of real time diagnostics and feedback algorithms for JET in view of the next step

    International Nuclear Information System (INIS)

    Murari, A.; Barana, O.; Murari, A.; Felton, R.; Zabeo, L.; Piccolo, F.; Sartori, F.; Joffrin, E.; Mazon, D.; Laborde, L.; Moreau, D.; Albanese, R.; Arena, P.; Bruno, M.; Ambrosino, G.; Ariola, M.; Crisanti, F.; Luna, E. de la; Sanchez, J.

    2004-01-01

    Real time control of many plasma parameters will be an essential aspect in the development of reliable high performance operation of Next Step Tokamaks. The main prerequisites for any feedback scheme are the precise real-time determination of the quantities to be controlled, requiring top quality and highly reliable diagnostics, and the availability of robust control algorithms. A new set of real time diagnostics was recently implemented on JET to prove the feasibility of determining, with high accuracy and time resolution, the most important plasma quantities. With regard to feedback algorithms, new model-based controllers were developed to allow a more robust control of several plasma parameters. Both diagnostics and algorithms were successfully used in several experiments, ranging from H-mode plasmas to configuration with ITBs (internal thermal barriers). Since elaboration of computationally heavy measurements is often required, significant attention was devoted to non-algorithmic methods like Digital or Cellular Neural/Nonlinear Networks. The real time hardware and software adopted architectures are also described with particular attention to their relevance to ITER. (authors)

  18. Development of real time diagnostics and feedback algorithms for JET in view of the next step

    Energy Technology Data Exchange (ETDEWEB)

    Murari, A.; Barana, O. [Consorzio RFX Associazione EURATOM ENEA per la Fusione, Corso Stati Uniti 4, Padua (Italy); Felton, R.; Zabeo, L.; Piccolo, F.; Sartori, F. [Euratom/UKAEA Fusion Assoc., Culham Science Centre, Abingdon, Oxon (United Kingdom); Joffrin, E.; Mazon, D.; Laborde, L.; Moreau, D. [Association EURATOM-CEA, CEA Cadarache, 13 - Saint-Paul-lez-Durance (France); Albanese, R. [Assoc. Euratom-ENEA-CREATE, Univ. Mediterranea RC (Italy); Arena, P.; Bruno, M. [Assoc. Euratom-ENEA-CREATE, Univ.di Catania (Italy); Ambrosino, G.; Ariola, M. [Assoc. Euratom-ENEA-CREATE, Univ. Napoli Federico Napoli (Italy); Crisanti, F. [Associazone EURATOM ENEA sulla Fusione, C.R. Frascati (Italy); Luna, E. de la; Sanchez, J. [Associacion EURATOM CIEMAT para Fusion, Madrid (Spain)

    2004-07-01

    Real time control of many plasma parameters will be an essential aspect in the development of reliable high performance operation of Next Step Tokamaks. The main prerequisites for any feedback scheme are the precise real-time determination of the quantities to be controlled, requiring top quality and highly reliable diagnostics, and the availability of robust control algorithms. A new set of real time diagnostics was recently implemented on JET to prove the feasibility of determining, with high accuracy and time resolution, the most important plasma quantities. With regard to feedback algorithms, new model-based controllers were developed to allow a more robust control of several plasma parameters. Both diagnostics and algorithms were successfully used in several experiments, ranging from H-mode plasmas to configuration with ITBs (internal thermal barriers). Since elaboration of computationally heavy measurements is often required, significant attention was devoted to non-algorithmic methods like Digital or Cellular Neural/Nonlinear Networks. The real time hardware and software adopted architectures are also described with particular attention to their relevance to ITER. (authors)

  19. Towards a comprehensive framework for cosimulation of dynamic models with an emphasis on time stepping

    Science.gov (United States)

    Hoepfer, Matthias

    co-simulation approach to modeling and simulation. It lays out the general approach to dynamic system co-simulation, and gives a comprehensive overview of what co-simulation is and what it is not. It creates a taxonomy of the requirements and limits of co-simulation, and the issues arising with co-simulating sub-models. Possible solutions towards resolving the stated problems are investigated to a certain depth. A particular focus is given to the issue of time stepping. It will be shown that for dynamic models, the selection of the simulation time step is a crucial issue with respect to computational expense, simulation accuracy, and error control. The reasons for this are discussed in depth, and a time stepping algorithm for co-simulation with unknown dynamic sub-models is proposed. Motivations and suggestions for the further treatment of selected issues are presented.

  20. Effect of the processing steps on compositions of table olive since harvesting time to pasteurization.

    Science.gov (United States)

    Nikzad, Nasim; Sahari, Mohammad A; Vanak, Zahra Piravi; Safafar, Hamed; Boland-nazar, Seyed A

    2013-08-01

    Weight, oil, fatty acids, tocopherol, polyphenol, and sterol properties of 5 olive cultivars (Zard, Fishomi, Ascolana, Amigdalolia, and Conservalia) during crude, lye treatment, washing, fermentation, and pasteurization steps were studied. Results showed: oil percent was higher and lower in Ascolana (crude step) and in Fishomi (pasteurization step), respectively; during processing steps, in all cultivars, oleic, palmitic, linoleic, and stearic acids were higher; the highest changes in saturated and unsaturated fatty acids were in fermentation step; the highest and the lowest ratios of ω3 / ω6 were in Ascolana (washing step) and in Zard (pasteurization step), respectively; the highest and the lowest tocopherol were in Amigdalolia and Fishomi, respectively, and major damage occurred in lye step; the highest and the lowest polyphenols were in Ascolana (crude step) and in Zard and Ascolana (pasteurization step), respectively; the major damage among cultivars occurred during lye step, in which the polyphenol reduced to 1/10 of first content; sterol did not undergo changes during steps. Reviewing of olive patents shows that many compositions of fruits such as oil quality, fatty acids, quantity and its fraction can be changed by alteration in cultivar and process.

  1. Avoid the tsunami of the Dirac sea in the imaginary time step method

    International Nuclear Information System (INIS)

    Zhang, Ying; Liang, Haozhao; Meng, Jie

    2010-01-01

    The discrete single-particle spectra in both the Fermi and Dirac sea have been calculated by the imaginary time step (ITS) method for the Schroedinger-like equation after avoiding the "tsunami" of the Dirac sea, i.e. the diving behavior of the single-particle level into the Dirac sea in the direct application of the ITS method for the Dirac equation. It is found that by the transform from the Dirac equation to the Schroedinger-like equation, the single-particle spectra, which extend from the positive to the negative infinity, can be separately obtained by the ITS evolution in either the Fermi sea or the Dirac sea. Identical results with those in the conventional shooting method have been obtained via the ITS evolution for the equivalent Schroedinger-like equation, which demonstrates the feasibility, practicality and reliability of the present algorithm and dispels the doubts on the ITS method in the relativistic system. (author)

  2. Computer experiments of the time-sequence of individual steps in multiple Coulomb-excitation

    International Nuclear Information System (INIS)

    Boer, J. de; Dannhaueser, G.

    1982-01-01

    The way in which the multiple E2 steps in the Coulomb-excitation of a rotational band of a nucleus follow one another is elucidated for selected examples using semiclassical computer experiments. The role a given transition plays for the excitation of a given final state is measured by a quantity named ''importance function''. It is found that these functions, calculated for the highest rotational state, peak at times forming a sequence for the successive E2 transitions starting from the ground state. This sequential behaviour is used to approximately account for the effects on the projectile orbit of the sequential transfer of excitation energy and angular momentum from projectile to target. These orbits lead to similar deflection functions and cross sections as those obtained from a symmetrization procedure approximately accounting for the transfer of angular momentum and energy. (Auth.)

  3. Detection and Correction of Step Discontinuities in Kepler Flux Time Series

    Science.gov (United States)

    Kolodziejczak, J. J.; Morris, R. L.

    2011-01-01

    PDC 8.0 includes an implementation of a new algorithm to detect and correct step discontinuities appearing in roughly one of every 20 stellar light curves during a given quarter. The majority of such discontinuities are believed to result from high-energy particles (either cosmic or solar in origin) striking the photometer and causing permanent local changes (typically -0.5%) in quantum efficiency, though a partial exponential recovery is often observed [1]. Since these features, dubbed sudden pixel sensitivity dropouts (SPSDs), are uncorrelated across targets they cannot be properly accounted for by the current detrending algorithm. PDC detrending is based on the assumption that features in flux time series are due either to intrinsic stellar phenomena or to systematic errors and that systematics will exhibit measurable correlations across targets. SPSD events violate these assumptions and their successful removal not only rectifies the flux values of affected targets, but demonstrably improves the overall performance of PDC detrending [1].

  4. Improving stability of stabilized and multiscale formulations in flow simulations at small time steps

    KAUST Repository

    Hsu, Ming-Chen

    2010-02-01

    The objective of this paper is to show that use of the element-vector-based definition of stabilization parameters, introduced in [T.E. Tezduyar, Computation of moving boundaries and interfaces and stabilization parameters, Int. J. Numer. Methods Fluids 43 (2003) 555-575; T.E. Tezduyar, Y. Osawa, Finite element stabilization parameters computed from element matrices and vectors, Comput. Methods Appl. Mech. Engrg. 190 (2000) 411-430], circumvents the well-known instability associated with conventional stabilized formulations at small time steps. We describe formulations for linear advection-diffusion and incompressible Navier-Stokes equations and test them on three benchmark problems: advection of an L-shaped discontinuity, laminar flow in a square domain at low Reynolds number, and turbulent channel flow at friction-velocity Reynolds number of 395. © 2009 Elsevier B.V. All rights reserved.

  5. Comparison between time-step-integration and probabilistic methods in seismic analysis of a linear structure

    International Nuclear Information System (INIS)

    Schneeberger, B.; Breuleux, R.

    1977-01-01

    Assuming that earthquake ground motion is a stationary time function, the seismic analysis of a linear structure can be done by probailistic methods using the 'power spectral density function' (PSD), instead of applying the more traditional time-step-integration using earthquake time histories (TH). A given structure was analysed both by PSD and TH methods computing and comparing 'floor response spectra'. The analysis using TH was performed for two different TH and different frequency intervals for the 'floor-response-spectra'. The analysis using PSD first produced PSD functions of the responses of the floors and these were then converted into 'foor-response-spectra'. Plots of the resulting 'floor-response-spectra' show: (1) The agreement of TH and PSD results is quite close. (2) The curves produced by PSD are much smoother than those produced by TH and mostly form an enelope of the latter. (3) The curves produced by TH are quite jagged with the location and magnitude of the peaks depending on the choice of frequencies at which the 'floor-response-spectra' were evaluated and on the choice of TH. (Auth.)

  6. Detection of Tomato black ring virus by real-time one-step RT-PCR.

    Science.gov (United States)

    Harper, Scott J; Delmiglio, Catia; Ward, Lisa I; Clover, Gerard R G

    2011-01-01

    A TaqMan-based real-time one-step RT-PCR assay was developed for the rapid detection of Tomato black ring virus (TBRV), a significant plant pathogen which infects a wide range of economically important crops. Primers and a probe were designed against existing genomic sequences to amplify a 72 bp fragment from RNA-2. The assay amplified all isolates of TBRV tested, but no amplification was observed from the RNA of other nepovirus species or healthy host plants. The detection limit of the assay was estimated to be around nine copies of the TBRV target region in total RNA. A comparison with conventional RT-PCR and ELISA, indicated that ELISA, the current standard test method, lacked specificity and reacted to all nepovirus species tested, while conventional RT-PCR was approximately ten-fold less sensitive than the real-time RT-PCR assay. Finally, the real-time RT-PCR assay was tested using five different RT-PCR reagent kits and was found to be robust and reliable, with no significant differences in sensitivity being found. The development of this rapid assay should aid in quarantine and post-border surveys for regulatory agencies. Copyright © 2010 Elsevier B.V. All rights reserved.

  7. Demonstration of non-Gaussian restricted diffusion in tumor cells using diffusion-time dependent diffusion weighted MR contrast

    Directory of Open Access Journals (Sweden)

    Tuva Roaldsdatter Hope

    2016-08-01

    Full Text Available The diffusion weighted imaging (DWI technique enables quantification of water mobility for probing microstructural properties of biological tissue, and has become an effective tool for collecting information about the underlying pathology of cancerous tissue. Measurements using multiple b-values have indicated a bi-exponential signal attenuation, ascribed to fast (high ADC and slow (low ADC diffusion components. In this empirical study, we investigate the properties of the diffusion time (∆ - dependent components of the diffusion-weighted (DW signal in a constant b-value experiment. A Xenograft GBM mouse was imaged using ∆ = 11 ms, 20 ms, 40 ms, 60 ms and b=500-4000 s/mm2 in intervals of 500s/mm2. Data was corrected for EPI distortions and the ∆-dependence on the DW signal was measured within three regions of interest (intermediate- and high-density tumor regions and normal appearing brain tissue regions (NAB. In this empirical study we verify the assumption that the slow decaying component of the DW-signal is non-Gaussian and dependent on ∆, consistent with restricted diffusion of the intracellular space. As the DW-signal as a function of ∆ is specific to restricted diffusion, manipulating ∆ at constant b-value (cb provides a complementary and direct approach for separating the restricted from the hindered diffusion component. Our results show that only tumor tissue signal of our data demonstrate ∆-dependence, based on a bi-exponential model with a restricted diffusion component, we successfully estimated the restricted ADC, signal volume fraction and cell size within each tumor ROI.

  8. Effects of the lateral amplitude and regularity of upper body fluctuation on step time variability evaluated using return map analysis.

    Science.gov (United States)

    Chidori, Kazuhiro; Yamamoto, Yuji

    2017-01-01

    The aim of this study was to evaluate the effects of the lateral amplitude and regularity of upper body fluctuation on step time variability. Return map analysis was used to clarify the relationship between step time variability and a history of falling. Eleven healthy, community-dwelling older adults and twelve younger adults participated in the study. All of the subjects walked 25 m at a comfortable speed. Trunk acceleration was measured using triaxial accelerometers attached to the third lumbar vertebrae (L3) and the seventh cervical vertebrae (C7). The normalized average magnitude of acceleration, the coefficient of determination ($R^2$) of the return map, and the step time variabilities, were calculated. Cluster analysis using the average fluctuation and the regularity of C7 fluctuation identified four walking patterns in the mediolateral (ML) direction. The participants with higher fluctuation and lower regularity showed significantly greater step time variability compared with the others. Additionally, elderly participants who had fallen in the past year had higher amplitude and a lower regularity of fluctuation during walking. In conclusion, by focusing on the time evolution of each step, it is possible to understand the cause of stride and/or step time variability that is associated with a risk of falls.

  9. Implementation of Real-Time Machining Process Control Based on Fuzzy Logic in a New STEP-NC Compatible System

    Directory of Open Access Journals (Sweden)

    Po Hu

    2016-01-01

    Full Text Available Implementing real-time machining process control at shop floor has great significance on raising the efficiency and quality of product manufacturing. A framework and implementation methods of real-time machining process control based on STEP-NC are presented in this paper. Data model compatible with ISO 14649 standard is built to transfer high-level real-time machining process control information between CAPP systems and CNC systems, in which EXPRESS language is used to define new STEP-NC entities. Methods for implementing real-time machining process control at shop floor are studied and realized on an open STEP-NC controller, which is developed using object-oriented, multithread, and shared memory technologies conjunctively. Cutting force at specific direction of machining feature in side mill is chosen to be controlled object, and a fuzzy control algorithm with self-adjusting factor is designed and embedded in the software CNC kernel of STEP-NC controller. Experiments are carried out to verify the proposed framework, STEP-NC data model, and implementation methods for real-time machining process control. The results of experiments prove that real-time machining process control tasks can be interpreted and executed correctly by the STEP-NC controller at shop floor, in which actual cutting force is kept around ideal value, whether axial cutting depth changes suddenly or continuously.

  10. Stepping reaction time and gait adaptability are significantly impaired in people with Parkinson's disease: Implications for fall risk.

    Science.gov (United States)

    Caetano, Maria Joana D; Lord, Stephen R; Allen, Natalie E; Brodie, Matthew A; Song, Jooeun; Paul, Serene S; Canning, Colleen G; Menant, Jasmine C

    2018-02-01

    Decline in the ability to take effective steps and to adapt gait, particularly under challenging conditions, may be important reasons why people with Parkinson's disease (PD) have an increased risk of falling. This study aimed to determine the extent of stepping and gait adaptability impairments in PD individuals as well as their associations with PD symptoms, cognitive function and previous falls. Thirty-three older people with PD and 33 controls were assessed in choice stepping reaction time, Stroop stepping and gait adaptability tests; measurements identified as fall risk factors in older adults. People with PD had similar mean choice stepping reaction times to healthy controls, but had significantly greater intra-individual variability. In the Stroop stepping test, the PD participants were more likely to make an error (48 vs 18%), took 715 ms longer to react (2312 vs 1517 ms) and had significantly greater response variability (536 vs 329 ms) than the healthy controls. People with PD also had more difficulties adapting their gait in response to targets (poorer stepping accuracy) and obstacles (increased number of steps) appearing at short notice on a walkway. Within the PD group, higher disease severity, reduced cognition and previous falls were associated with poorer stepping and gait adaptability performances. People with PD have reduced ability to adapt gait to unexpected targets and obstacles and exhibit poorer stepping responses, particularly in a test condition involving conflict resolution. Such impaired stepping responses in Parkinson's disease are associated with disease severity, cognitive impairment and falls. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. On an adaptive time stepping strategy for solving nonlinear diffusion equations

    International Nuclear Information System (INIS)

    Chen, K.; Baines, M.J.; Sweby, P.K.

    1993-01-01

    A new time step selection procedure is proposed for solving non- linear diffusion equations. It has been implemented in the ASWR finite element code of Lorenz and Svoboda [10] for 2D semiconductor process modelling diffusion equations. The strategy is based on equi-distributing the local truncation errors of the numerical scheme. The use of B-splines for interpolation (as well as for the trial space) results in a banded and diagonally dominant matrix. The approximate inverse of such a matrix can be provided to a high degree of accuracy by another banded matrix, which in turn can be used to work out the approximate finite difference scheme corresponding to the ASWR finite element method, and further to calculate estimates of the local truncation errors of the numerical scheme. Numerical experiments on six full simulation problems arising in semiconductor process modelling have been carried out. Results show that our proposed strategy is more efficient and better conserves the total mass. 18 refs., 6 figs., 2 tabs

  12. Restrictive Cardiomyopathy

    Science.gov (United States)

    ... up in the circulatory system. In time, the heart fails. What causes it? Restrictive cardiomyopathy is often caused by diseases in other parts of the body. One known cause is cardiac ... build up in the heart tissue, making the tissue stiff and thickened. Cardiac ...

  13. Traffic safety and step-by-step driving licence for young people

    DEFF Research Database (Denmark)

    Tønning, Charlotte; Agerholm, Niels

    2017-01-01

    presents a review of safety effects from step-by-step driving licence schemes. Most of the investigated schemes consist of a step-by-step driving licence with Step 1) various tests and education, Step 2) a period where driving is only allowed together with an experienced driver and Step 3) driving without...... companion is allowed but with various restrictions and, in some cases, additional driving education and tests. In general, a step-by-step driving licence improves traffic safety even though the young people are permitted to drive a car earlier on. The effects from driving with an experienced driver vary......Young novice car drivers are much more accident-prone than other drivers - up to 10 times that of their parents' generation. A central solution to improve the traffic safety for this group is implementation of a step-by-step driving licence. A number of countries have introduced a step...

  14. Timing of the steps in transformation of C3H 10T1/2 cells by X-irradiation

    International Nuclear Information System (INIS)

    Kennedy, A.R.; Cairns, J.; Little, J.B.

    1984-01-01

    Transformation of cells in culture by chemical carcinogens or X-rays seems to require at least two steps. The initial step is a frequent event; for example, after transient exposure to either methylcholanthrene or X-rays. It has been hypothesized that the second step behaves like a spontaneous mutation in having a constant but small probability of occurring each time an initiated cell divides. We show here that the clone size distribution of transformed cells in growing cultures initiated by X-rays, is, indeed, exactly what would be expected on that hypothesis. (author)

  15. Rotor cascade shape optimization with unsteady passing wakes using implicit dual time stepping method

    Science.gov (United States)

    Lee, Eun Seok

    2000-10-01

    An improved aerodynamics performance of a turbine cascade shape can be achieved by an understanding of the flow-field associated with the stator-rotor interaction. In this research, an axial gas turbine airfoil cascade shape is optimized for improved aerodynamic performance by using an unsteady Navier-Stokes solver and a parallel genetic algorithm. The objective of the research is twofold: (1) to develop a computational fluid dynamics code having faster convergence rate and unsteady flow simulation capabilities, and (2) to optimize a turbine airfoil cascade shape with unsteady passing wakes for improved aerodynamic performance. The computer code solves the Reynolds averaged Navier-Stokes equations. It is based on the explicit, finite difference, Runge-Kutta time marching scheme and the Diagonalized Alternating Direction Implicit (DADI) scheme, with the Baldwin-Lomax algebraic and k-epsilon turbulence modeling. Improvements in the code focused on the cascade shape design capability, convergence acceleration and unsteady formulation. First, the inverse shape design method was implemented in the code to provide the design capability, where a surface transpiration concept was employed as an inverse technique to modify the geometry satisfying the user specified pressure distribution on the airfoil surface. Second, an approximation storage multigrid method was implemented as an acceleration technique. Third, the preconditioning method was adopted to speed up the convergence rate in solving the low Mach number flows. Finally, the implicit dual time stepping method was incorporated in order to simulate the unsteady flow-fields. For the unsteady code validation, the Stokes's 2nd problem and the Poiseuille flow were chosen and compared with the computed results and analytic solutions. To test the code's ability to capture the natural unsteady flow phenomena, vortex shedding past a cylinder and the shock oscillation over a bicircular airfoil were simulated and compared with

  16. The Parity of Set Systems under Random Restrictions with Applications to Exponential Time Problems

    DEFF Research Database (Denmark)

    Björklund, Andreas; Dell, Holger; Husfeldt, Thore

    2015-01-01

    problems. We find three applications of our reductions: 1. An exponential-time algorithm: We show how to decide Hamiltonicity in directed n-vertex graphs with running time 1.9999^n provided that the graph has at most 1.0385^n Hamiltonian cycles. We do so by reducing to the algorithm of Björklund...

  17. Different types of errors in saccadic task are sensitive to either time of day or chronic sleep restriction.

    Directory of Open Access Journals (Sweden)

    Barbara Wachowicz

    Full Text Available Circadian rhythms and restricted sleep length affect cognitive functions and, consequently, the performance of day to day activities. To date, no more than a few studies have explored the consequences of these factors on oculomotor behaviour. We have implemented a spatial cuing paradigm in an eye tracking experiment conducted four times of the day after one week of rested wakefulness and after one week of chronic partial sleep restriction. Our aim was to verify whether these conditions affect the number of a variety of saccadic task errors. Interestingly, we found that failures in response selection, i.e. premature responses and direction errors, were prone to time of day variations, whereas failures in response execution, i.e. omissions and commissions, were considerably affected by sleep deprivation. The former can be linked to the cue facilitation mechanism, while the latter to wake state instability and the diminished ability of top-down inhibition. Together, these results may be interpreted in terms of distinctive sensitivity of orienting and alerting systems to fatigue. Saccadic eye movements proved to be a novel and effective measure with which to study the susceptibility of attentional systems to time factors, thus, this approach is recommended for future research.

  18. Theoretical restrictions on longest implicit time scales in Markov state models of biomolecular dynamics

    Science.gov (United States)

    Sinitskiy, Anton V.; Pande, Vijay S.

    2018-01-01

    Markov state models (MSMs) have been widely used to analyze computer simulations of various biomolecular systems. They can capture conformational transitions much slower than an average or maximal length of a single molecular dynamics (MD) trajectory from the set of trajectories used to build the MSM. A rule of thumb claiming that the slowest implicit time scale captured by an MSM should be comparable by the order of magnitude to the aggregate duration of all MD trajectories used to build this MSM has been known in the field. However, this rule has never been formally proved. In this work, we present analytical results for the slowest time scale in several types of MSMs, supporting the above rule. We conclude that the slowest implicit time scale equals the product of the aggregate sampling and four factors that quantify: (1) how much statistics on the conformational transitions corresponding to the longest implicit time scale is available, (2) how good the sampling of the destination Markov state is, (3) the gain in statistics from using a sliding window for counting transitions between Markov states, and (4) a bias in the estimate of the implicit time scale arising from finite sampling of the conformational transitions. We demonstrate that in many practically important cases all these four factors are on the order of unity, and we analyze possible scenarios that could lead to their significant deviation from unity. Overall, we provide for the first time analytical results on the slowest time scales captured by MSMs. These results can guide further practical applications of MSMs to biomolecular dynamics and allow for higher computational efficiency of simulations.

  19. Night-time restricted feeding normalises clock genes and Pai-1 gene expression in the db/db mouse liver.

    Science.gov (United States)

    Kudo, T; Akiyama, M; Kuriyama, K; Sudo, M; Moriya, T; Shibata, S

    2004-08-01

    An increase in PAI-1 activity is thought to be a key factor underlying myocardial infarction. Mouse Pai-1 (mPai-1) activity shows a daily rhythm in vivo, and its transcription seems to be controlled not only by clock genes but also by humoral factors such as insulin and triglycerides. Thus, we investigated daily clock genes and mPai-1 mRNA expression in the liver of db/db mice exhibiting high levels of glucose, insulin and triglycerides. Locomotor activity was measured using an infrared detection system. RT-PCR or in situ hybridisation methods were applied to measure gene expression. Humoral factors were measured using measurement kits. The db/ db mice showed attenuated locomotor activity rhythms. The rhythmic expression of mPer2 mRNA was severely diminished and the phase of mBmal1 oscillation was advanced in the db/db mouse liver, whereas mPai-1 mRNA was highly and constitutively expressed. Night-time restricted feeding led to a recovery not only from the diminished locomotor activity, but also from the diminished Per2 and advanced mBmal1 mRNA rhythms. Expression of mPai-1 mRNA in db/db mice was reduced to levels far below normal. Pioglitazone treatment slightly normalised glucose and insulin levels, with a slight reduction in mPai-1 gene expression. We demonstrated that Type 2 diabetes impairs the oscillation of the peripheral oscillator. Night-time restricted feeding rather than pioglitazone injection led to a recovery from the diminished locomotor activity, and altered oscillation of the peripheral clock and mPai-1 mRNA rhythm. Thus, we conclude that scheduled restricted food intake may be a useful form of treatment for diabetes.

  20. BIOMAP A Daily Time Step, Mechanistic Model for the Study of Ecosystem Dynamics

    Science.gov (United States)

    Wells, J. R.; Neilson, R. P.; Drapek, R. J.; Pitts, B. S.

    2010-12-01

    of both climate and ecosystems must be done at coarse grid resolutions; smaller domains require higher resolution for the simulation of natural resource processes at the landscape scale and that of on-the-ground management practices. Via a combined multi-agency and private conservation effort we have implemented a Nested Scale Experiment (NeScE) that ranges from 1/2 degree resolution (global, ca. 50 km) to ca. 8km (North America) and 800 m (conterminous U.S.). Our first DGVM, MC1, has been implemented at all 3 scales. We are just beginning to implement BIOMAP into NeScE, with its unique features, and daily time step, as a counterpoint to MC1. We believe it will be more accurate at all resolutions providing better simulations of vegetation distribution, carbon balance, runoff, fire regimes and drought impacts.

  1. Care package for anxiety disorders: no-show and dropout of standardised, time restricted treatment

    DEFF Research Database (Denmark)

    Tranberg, Hanne; Mortensen, Erik Lykke; Lau, Marianne Engelbrecht

    Background: Psychotherapy has shown to be efficacious but therapy effectiveness in mental health services is compromised by patients who fail to show up for assessment, treatment start and stay in treatment. Predictors for patient non-attendance (no-show and dropout) have been identified as patient...... or therapist characteristics. Organisational variables are sparsely studied although waiting time may affect no-show and dropout. In order to reduce waiting time the Mental Health Services in Denmark have introduced care packages in the treatment of non-psychotic disorders. Care packages are courses...... and if demographic and clinical variables were predictors for no-show and dropout. Methods: The study was a quasi-experimental pre-post study in a naturalistic setting in the Mental Health Services, Capital Region of Denmark. Two samples of patients, aged above 18 years and referred for treatment for anxiety...

  2. A personal tourism navigation system to support traveling multiple destinations with time restrictions

    OpenAIRE

    Maruyama, Atsushi; Shibata, Naoki; Murata, Yoshihiro; Yasumoto, Keiichi; Ito, Minoru

    2004-01-01

    We propose a personal navigation system (called PNS) which navigates a tourist through multiple destinations efficiently. In our PNS, a tourist can specify multiple destinations with desired arrival/stay time and preference degree. The system calculates the route including part of the destinations satisfying tourist's requirements and navigates him/her. For the above route search problem, we have developed an efficient route search algorithm using a genetic algorithm. We have designed and imp...

  3. Revising superior planning performance in chess players: the impact of time restriction and motivation aspects.

    Science.gov (United States)

    Unterrainer, Josef Martin; Kaller, Christoph Philipp; Leonhart, Rainer; Rahm, Benjamin

    2011-01-01

    In a previous study (Unterrainer, Kaller, Halsband, & Rahm, 2006), chess players outperformed non-chess players in the Tower of London planning task but exhibited disproportionately longer processing times. This pattern of results raises the question of whether chess players' planning capabilities are superior or whether the results reflect differences in the speed-accuracy trade-off between the groups, possibly attributable to sports motivation. The present study was designed to disambiguate these alternative suggestions by implementing various constraints on planning time and by assessing self-reported motivation. In contrast to the previous study, chess players' performance was not superior, independently of whether problems had to be solved with (Experiment 1) or without (Experiment 2) time limits. As expected, chess players reported higher overall trait and state motivation scores across both experiments. These findings revise the notion of superior planning performance in chess players. In consequence, they do not conform with the assumption of a general transfer of chess-related planning expertise to other cognitive domains, instead suggesting that superior performance may be possible only under specific circumstances such as receiving competitive instructions.

  4. Exercise restriction is not associated with increasing body mass index over time in patients with anomalous aortic origin of the coronary arteries.

    Science.gov (United States)

    Meza, James M; Elias, Matthew D; Wilder, Travis J; O'Brien, James E; Kim, Richard W; Mavroudis, Constantine; Williams, William G; Brothers, Julie; Cohen, Meryl S; McCrindle, Brian W

    2017-10-01

    Anomalous aortic origin of the coronary arteries is associated with exercise-induced ischaemia, leading some physicians to restrict exercise in patients with this condition. We sought to determine whether exercise restriction was associated with increasing body mass index over time. From 1998 to 2015, 440 patients ⩽30 years old were enrolled into an inception cohort. Exercise-restriction status was documented in 143 patients. Using linear mixed model repeated-measures regression, factors associated with increasing body mass index z-score over time, including exercise restriction and surgical intervention as time-varying covariates, were investigated. The 143 patients attended 558 clinic visits for which exercise-restriction status was recorded. The mean number of clinic visits per patient was 4, and the median duration of follow-up was 1.7 years (interquartile range (IQR) 0.5-4.4). The median age at first clinic visit was 10.3 years (IQR 7.1-13.9), and 71% (101/143) were males. All patients were alive at their most recent follow-up. At the first clinic visit, 54% (78/143) were exercise restricted, and restriction status changed in 34% (48/143) during follow-up. The median baseline body mass index z-score was 0.2 (IQR 0.3-0.9). In repeated-measures analysis, neither time-related exercise restriction nor its interaction with time was associated with increasing body mass index z-score. Surgical intervention and its interaction with time were associated with decreasing body mass index z-score. Although exercise restriction was not associated with increasing body mass index over time, surgical intervention was associated with decreasing body mass index z-score over time in patients with anomalous aortic origin of the coronary arteries.

  5. Time-restricted feeding improves insulin resistance and hepatic steatosis in a mouse model of postmenopausal obesity.

    Science.gov (United States)

    Chung, Heekyung; Chou, Winjet; Sears, Dorothy D; Patterson, Ruth E; Webster, Nicholas J G; Ellies, Lesley G

    2016-12-01

    Menopause is associated with significant hormonal changes that result in increased total body fat and abdominal fat, amplifying the risk for metabolic syndrome and diseases such as diabetes, cardiovascular disease and cancer in postmenopausal women. Intermittent fasting regimens hold significant health benefit promise for obese humans, however, regimens that include extreme daytime calorie restriction or daytime fasting are generally associated with hunger and irritability, hampering long-term compliance and adoption in the clinical setting. Time-restricted feeding (TRF), a regimen allowing eating only during a specific period in the normal circadian feeding cycle, without calorie restriction, may increase compliance and provide a more clinically viable method for reducing the detrimental metabolic consequences associated with obesity. We tested TRF as an intervention in a mouse model of postmenopausal obesity. Metabolic parameters were measured using Clinical Laboratory Animal Monitoring System (CLAMS) and we carried out glucose tolerance tests. We also stained liver sections with oil red O to examine steatosis and measured gene expression related to gluconeogenesis. Preexisting metabolic disease was significantly attenuated during 7 weeks of TRF. Despite having access to the same high fat diet (HFD) as ad libitum fed (ALF) mice, TRF mice experienced rapid weight loss followed by a delayed improvement in insulin resistance and a reduced severity of hepatic steatosis by having access to the HFD for only 8h during their normal nocturnal feeding period. The lower respiratory exchange ratio in the TRF group compared with the ALF group early in the dark phase suggested that fat was the predominant fuel source in the TRF group and correlated with gene expression analyses that suggested a switch from gluconeogenesis to ketogenesis. In addition, TRF mice were more physically active than ALF fed mice. Our data support further analysis of TRF as a clinically viable form of

  6. Development and evaluation of a real-time one step Reverse-Transcriptase PCR for quantitation of Chandipura Virus

    Directory of Open Access Journals (Sweden)

    Tandale Babasaheb V

    2008-12-01

    Full Text Available Abstract Background Chandipura virus (CHPV, a member of family Rhabdoviridae was attributed to an explosive outbreak of acute encephalitis in children in Andhra Pradesh, India in 2003 and a small outbreak among tribal children from Gujarat, Western India in 2004. The case-fatality rate ranged from 55–75%. Considering the rapid progression of the disease and high mortality, a highly sensitive method for quantifying CHPV RNA by real-time one step reverse transcriptase PCR (real-time one step RT-PCR using TaqMan technology was developed for rapid diagnosis. Methods Primers and probe for P gene were designed and used to standardize real-time one step RT-PCR assay for CHPV RNA quantitation. Standard RNA was prepared by PCR amplification, TA cloning and run off transcription. The optimized real-time one step RT-PCR assay was compared with the diagnostic nested RT-PCR and different virus isolation systems [in vivo (mice in ovo (eggs, in vitro (Vero E6, PS, RD and Sand fly cell line] for the detection of CHPV. Sensitivity and specificity of real-time one step RT-PCR assay was evaluated with diagnostic nested RT-PCR, which is considered as a gold standard. Results Real-time one step RT-PCR was optimized using in vitro transcribed (IVT RNA. Standard curve showed linear relationship for wide range of 102-1010 (r2 = 0.99 with maximum Coefficient of variation (CV = 5.91% for IVT RNA. The newly developed real-time RT-PCR was at par with nested RT-PCR in sensitivity and superior to cell lines and other living systems (embryonated eggs and infant mice used for the isolation of the virus. Detection limit of real-time one step RT-PCR and nested RT-PCR was found to be 1.2 × 100 PFU/ml. RD cells, sand fly cells, infant mice, and embryonated eggs showed almost equal sensitivity (1.2 × 102 PFU/ml. Vero and PS cell-lines (1.2 × 103 PFU/ml were least sensitive to CHPV infection. Specificity of the assay was found to be 100% when RNA from other viruses or healthy

  7. Comparing an Annual and a Daily Time-Step Model for Predicting Field-Scale Phosphorus Loss.

    Science.gov (United States)

    Bolster, Carl H; Forsberg, Adam; Mittelstet, Aaron; Radcliffe, David E; Storm, Daniel; Ramirez-Avila, John; Sharpley, Andrew N; Osmond, Deanna

    2017-11-01

    A wide range of mathematical models are available for predicting phosphorus (P) losses from agricultural fields, ranging from simple, empirically based annual time-step models to more complex, process-based daily time-step models. In this study, we compare field-scale P-loss predictions between the Annual P Loss Estimator (APLE), an empirically based annual time-step model, and the Texas Best Management Practice Evaluation Tool (TBET), a process-based daily time-step model based on the Soil and Water Assessment Tool. We first compared predictions of field-scale P loss from both models using field and land management data collected from 11 research sites throughout the southern United States. We then compared predictions of P loss from both models with measured P-loss data from these sites. We observed a strong and statistically significant ( loss between the two models; however, APLE predicted, on average, 44% greater dissolved P loss, whereas TBET predicted, on average, 105% greater particulate P loss for the conditions simulated in our study. When we compared model predictions with measured P-loss data, neither model consistently outperformed the other, indicating that more complex models do not necessarily produce better predictions of field-scale P loss. Our results also highlight limitations with both models and the need for continued efforts to improve their accuracy. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  8. The association between choice stepping reaction time and falls in older adults--a path analysis model

    NARCIS (Netherlands)

    Pijnappels, M.A.G.M.; Delbaere, K.; Sturnieks, D.L.; Lord, S.R.

    2010-01-01

    Background: choice stepping reaction time (CSRT) is a functional measure that has been shown to significantly discriminate older fallers from non-fallers. Objective: to investigate how physiological and cognitive factors mediate the association between CSRT performance and multiple falls by use of

  9. 3D elastic wave modeling using modified high‐order time stepping schemes with improved stability conditions

    KAUST Repository

    Chu, Chunlei; Stoffa, Paul L.; Seif, Roustam

    2009-01-01

    We present two Lax‐Wendroff type high‐order time stepping schemes and apply them to solving the 3D elastic wave equation. The proposed schemes have the same format as the Taylor series expansion based schemes, only with modified temporal extrapolation coefficients. We demonstrate by both theoretical analysis and numerical examples that the modified schemes significantly improve the stability conditions.

  10. Iteratively improving Hi-C experiments one step at a time.

    Science.gov (United States)

    Golloshi, Rosela; Sanders, Jacob T; McCord, Rachel Patton

    2018-04-30

    The 3D organization of eukaryotic chromosomes affects key processes such as gene expression, DNA replication, cell division, and response to DNA damage. The genome-wide chromosome conformation capture (Hi-C) approach can characterize the landscape of 3D genome organization by measuring interaction frequencies between all genomic regions. Hi-C protocol improvements and rapid advances in DNA sequencing power have made Hi-C useful to study diverse biological systems, not only to elucidate the role of 3D genome structure in proper cellular function, but also to characterize genomic rearrangements, assemble new genomes, and consider chromatin interactions as potential biomarkers for diseases. Yet, the Hi-C protocol is still complex and subject to variations at numerous steps that can affect the resulting data. Thus, there is still a need for better understanding and control of factors that contribute to Hi-C experiment success and data quality. Here, we evaluate recently proposed Hi-C protocol modifications as well as often overlooked variables in sample preparation and examine their effects on Hi-C data quality. We examine artifacts that can occur during Hi-C library preparation, including microhomology-based artificial template copying and chimera formation that can add noise to the downstream data. Exploring the mechanisms underlying Hi-C artifacts pinpoints steps that should be further optimized in the future. To improve the utility of Hi-C in characterizing the 3D genome of specialized populations of cells or small samples of primary tissue, we identify steps prone to DNA loss which should be considered to adapt Hi-C to lower cell numbers. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Seven steps to raise world security. Op-Ed, published in the Finanical Times

    International Nuclear Information System (INIS)

    ElBaradei, M.

    2005-01-01

    In recent years, three phenomena have radically altered the security landscape. They are the emergence of a nuclear black market, the determined efforts by more countries to acquire technology to produce the fissile material usable in nuclear weapons and the clear desire of terrorists to acquire weapons of mass destruction. The IAEA has been trying to solve these new problems with existing tools. But for every step forward, we have exposed vulnerabilities in the system. The system itself - the regime that implements non-proliferation treaty needs reinforcement. Some of the necessary remedies can be taken in New York at the Meeting to be held in May, but only if governments are ready to act. With seven straightforward steps, and without amending the treaty, this conference could reach a milestone in strengthening world security. The first step: put a five-year hold on additional facilities for uranium enrichment and plutonium separation. Second, speed up existing efforts, led by the US global threat reduction initiative and others, to modify the research reactors worldwide operating with highly enriched uranium - particularly those with metal fuel that could be readily employed as bomb material. Third, raise the bar for inspection standards by establishing the 'additional protocol' as the norm for verifying compliance with the NPT. Fourth, call on the United Nations Security Council to act swiftly and decisively in the case of any country that withdraws from the NPT, in terms of the threat the withdrawal poses to international peace and security. Fifth, urge states to act on the Security Council's recent resolution 1540, to pursue and prosecute any illicit trading in nuclear material and technology. Sixth, call on the five nuclear weapon states party to the NPT to accelerate implementation of their 'unequivocal commitment' to nuclear disarmament, building on efforts such as the 2002 Moscow treaty between Russia and the US. Last, acknowledge the volatility of

  12. Three-step management of pneumothorax: time for a re-think on initial management†

    Science.gov (United States)

    Kaneda, Hiroyuki; Nakano, Takahito; Taniguchi, Yohei; Saito, Tomohito; Konobu, Toshifumi; Saito, Yukihito

    2013-01-01

    Pneumothorax is a common disease worldwide, but surprisingly, its initial management remains controversial. There are some published guidelines for the management of spontaneous pneumothorax. However, they differ in some respects, particularly in initial management. In published trials, the objective of treatment has not been clarified and it is not possible to compare the treatment strategies between different trials because of inappropriate evaluations of the air leak. Therefore, there is a need to outline the optimal management strategy for pneumothorax. In this report, we systematically review published randomized controlled trials of the different treatments of primary spontaneous pneumothorax, point out controversial issues and finally propose a three-step strategy for the management of pneumothorax. There are three important characteristics of pneumothorax: potentially lethal respiratory dysfunction; air leak, which is the obvious cause of the disease; frequent recurrence. These three characteristics correspond to the three steps. The central idea of the strategy is that the lung should not be expanded rapidly, unless absolutely necessary. The primary objective of both simple aspiration and chest drainage should be the recovery of acute respiratory dysfunction or the avoidance of respiratory dysfunction and subsequent complications. We believe that this management strategy is simple and clinically relevant and not dependent on the classification of pneumothorax. PMID:23117233

  13. Modeling Stepped Leaders Using a Time Dependent Multi-dipole Model and High-speed Video Data

    Science.gov (United States)

    Karunarathne, S.; Marshall, T.; Stolzenburg, M.; Warner, T. A.; Orville, R. E.

    2012-12-01

    In summer of 2011, we collected lightning data with 10 stations of electric field change meters (bandwidth of 0.16 Hz - 2.6 MHz) on and around NASA/Kennedy Space Center (KSC) covering nearly 70 km × 100 km area. We also had a high-speed video (HSV) camera recording 50,000 images per second collocated with one of the electric field change meters. In this presentation we describe our use of these data to model the electric field change caused by stepped leaders. Stepped leaders of a cloud to ground lightning flash typically create the initial path for the first return stroke (RS). Most of the time, stepped leaders have multiple complex branches, and one of these branches will create the ground connection for the RS to start. HSV data acquired with a short focal length lens at ranges of 5-25 km from the flash are useful for obtaining the 2-D location of these multiple branches developing at the same time. Using HSV data along with data from the KSC Lightning Detection and Ranging (LDAR2) system and the Cloud to Ground Lightning Surveillance System (CGLSS), the 3D path of a leader may be estimated. Once the path of a stepped leader is obtained, the time dependent multi-dipole model [ Lu, Winn,and Sonnenfeld, JGR 2011] can be used to match the electric field change at various sensor locations. Based on this model, we will present the time-dependent charge distribution along a leader channel and the total charge transfer during the stepped leader phase.

  14. Anticonvulsant effect of time-restricted feeding in a pilocarpine-induced seizure model: Metabolic and epigenetic implications.

    Directory of Open Access Journals (Sweden)

    Jorge eLandgrave-Gómez

    2016-01-01

    Full Text Available A new generation of antiepileptic drugs has emerged; however, one-third of epilepsy patients do not properly respond to pharmacological treatments. The purpose of the present study was to investigate whether time-restricted feeding has an anticonvulsant effect and whether this restrictive diet promotes changes in energy metabolism and epigenetic modifications in a pilocarpine-induced seizure model. To resolve our hypothesis, one group of rats had free access to food and water ad libitum (AL and a second group underwent a time-restricted feeding (TRF schedule. We used the lithium-pilocarpine model to induce status epilepticus (SE, and behavioral seizure monitoring was analyzed. Additionally, an electroencephalography (EEG recording was performed to verify the effect of TRF on cortical electrical activity after a pilocarpine injection. For biochemical analysis, animals were sacrificed 24 hours after SE and hippocampal homogenates were used to evaluate the proteins related to metabolism and chromatin structure. Our results showed that TRF had an anticonvulsant effect as measured by the prolonged latency of forelimb clonus seizure, a decrease in the seizure severity score and fewer animals reaching SE. Additionally, the power of the late phase EEG recordings in the AL group was significantly higher than the TRF group. Moreover, we found that TRF is capable of inducing alterations in signaling pathways that regulate energy metabolism, including an increase in the phosphorylation of AMP dependent kinase (AMPK and a decrease in the phosphorylation of Akt kinase. Furthermore, we found that TRF was able to significantly increase the beta hydroxybutyrate (β-HB concentration, an endogenous inhibitor of histone deacetylases (HDACs. Finally, we found a significant decrease in HDAC activity as well as an increase in acetylation on histone 3 (H3 in hippocampal homogenates from the TRF group. These findings suggest that alterations in energy metabolism and the

  15. Impact of first-step potential and time on the vertical growth of ZnO nanorods on ITO substrate by two-step electrochemical deposition

    International Nuclear Information System (INIS)

    Kim, Tae Gyoum; Jang, Jin-Tak; Ryu, Hyukhyun; Lee, Won-Jae

    2013-01-01

    Highlights: •We grew vertical ZnO nanorods on ITO substrate using a two-step continuous potential process. •The nucleation for the ZnO nanorods growth was changed by first-step potential and duration. •The vertical ZnO nanorods were well grown when first-step potential was −1.2 V and 10 s. -- Abstract: In this study, we analyzed the growth of ZnO nanorods on an ITO (indium doped tin oxide) substrate by electrochemical deposition using a two-step, continuous potential process. We examined the effect of changing the first-step potential as well as the first-step duration on the morphological, structural and optical properties of ZnO nanorods, measured via using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) and photoluminescence (PL), respectively. As a result, vertical ZnO nanorods were grown on ITO substrate without the need for a template when the first-step potential was set to −1.2 V for a duration of 10 s, and the second-step potential was set to −0.7 V for a duration of 1190 s. The ZnO nanorods on this sample showed the highest XRD (0 0 2)/(1 0 0) peak intensity ratio and the highest PL near band edge emission to deep level emission peak intensity ratio (NBE/DLE). In this study, the nucleation for vertical ZnO nanorod growth on an ITO substrate was found to be affected by changes in the first-step potential and first-step duration

  16. Using Variable Dwell Time to Accelerate Gaze-based Web Browsing with Two-step Selection

    OpenAIRE

    Chen, Zhaokang; Shi, Bertram E.

    2017-01-01

    In order to avoid the "Midas Touch" problem, gaze-based interfaces for selection often introduce a dwell time: a fixed amount of time the user must fixate upon an object before it is selected. Past interfaces have used a uniform dwell time across all objects. Here, we propose an algorithm for adjusting the dwell times of different objects based on the inferred probability that the user intends to select them. In particular, we introduce a probabilistic model of natural gaze behavior while sur...

  17. A flexible and coherent test/estimation procedure based on restricted mean survival times for censored time-to-event data in randomized clinical trials.

    Science.gov (United States)

    Horiguchi, Miki; Cronin, Angel M; Takeuchi, Masahiro; Uno, Hajime

    2018-04-22

    In randomized clinical trials where time-to-event is the primary outcome, almost routinely, the logrank test is prespecified as the primary test and the hazard ratio is used to quantify treatment effect. If the ratio of 2 hazard functions is not constant, the logrank test is not optimal and the interpretation of hazard ratio is not obvious. When such a nonproportional hazards case is expected at the design stage, the conventional practice is to prespecify another member of weighted logrank tests, eg, Peto-Prentice-Wilcoxon test. Alternatively, one may specify a robust test as the primary test, which can capture various patterns of difference between 2 event time distributions. However, most of those tests do not have companion procedures to quantify the treatment difference, and investigators have fallen back on reporting treatment effect estimates not associated with the primary test. Such incoherence in the "test/estimation" procedure may potentially mislead clinicians/patients who have to balance risk-benefit for treatment decision. To address this, we propose a flexible and coherent test/estimation procedure based on restricted mean survival time, where the truncation time τ is selected data dependently. The proposed procedure is composed of a prespecified test and an estimation of corresponding robust and interpretable quantitative treatment effect. The utility of the new procedure is demonstrated by numerical studies based on 2 randomized cancer clinical trials; the test is dramatically more powerful than the logrank, Wilcoxon tests, and the restricted mean survival time-based test with a fixed τ, for the patterns of difference seen in these cancer clinical trials. Copyright © 2018 John Wiley & Sons, Ltd.

  18. The effect of restricted milk feeding through conventional or step-down methods with or without forage provision in starter feed on performance of Holstein bull calves.

    Science.gov (United States)

    Daneshvar, D; Khorvash, M; Ghasemi, E; Mahdavi, A H; Moshiri, B; Mirzaei, M; Pezeshki, A; Ghaffari, M H

    2015-08-01

    The objective of the current study was to examine whether step-down (STP) milk feeding method together with forage provision would improve performance, rumen fermentation, nutrient digestibility, blood metabolites, and structural growth of calves. Holstein bull calves ( = 40) were randomly assigned to 1 of 4 treatments in a completely randomized design with a 2 × 2 factorial arrangement. Treatments were 1) conventional (COV) milk feeding without forage provision (COV-NF), 2) COV milk feeding with forage provision, 3) STP milk feeding without forage provision, and 4) STP milk feeding with forage provision. Calves in the COV method ( = 20) received 5.5 L/d milk until d 56 of age followed by 2 L/d milk from d 56 to 59 of age. Calves in the STP method ( = 20) received 7 L/d milk until d 35, 4 L/d milk from d 35 to 48, and 2 L/d milk from d 50 to 59 of age. All the calves received the starter ration from d 3 of the study until d 74 of age. Forage-supplemented calves ( = 10/milk feeding method) received 15% alfalfa hay mixed with finely ground starter as a total mixed ration. All calves were weaned on d 60 of age and remained in the study until d 74. Regardless of the milk feeding method, the final BW (92.54 vs. 83.14 kg/d), starter intake (0.90 vs. 0.65 kg/d), total DMI (1.43 vs. 1.17 kg/d), and ADG (0.73 vs. 0.60 kg/d) were greater ( calves than those that received no forage during the preweaning, postweaning, and overall periods. Milk feeding method had no effect on ruminal pH, total VFA, acetate, or acetate:propionate ratio as well as body measurements. Ruminal pH and the molar proportions of acetate were greater ( calves than those that received no forage during the pre- and postweaning periods. Regardless of forage provision, STP methods increased ( feeding methods and forage provision with respect to BW, DMI, G:F, apparent nutrient digestibility (DM, OM, and CP), and body measurements. The interaction of milk feeding method and forage provision was significant

  19. Continuous-Time Random Walk with multi-step memory: an application to market dynamics

    Science.gov (United States)

    Gubiec, Tomasz; Kutner, Ryszard

    2017-11-01

    An extended version of the Continuous-Time Random Walk (CTRW) model with memory is herein developed. This memory involves the dependence between arbitrary number of successive jumps of the process while waiting times between jumps are considered as i.i.d. random variables. This dependence was established analyzing empirical histograms for the stochastic process of a single share price on a market within the high frequency time scale. Then, it was justified theoretically by considering bid-ask bounce mechanism containing some delay characteristic for any double-auction market. Our model appeared exactly analytically solvable. Therefore, it enables a direct comparison of its predictions with their empirical counterparts, for instance, with empirical velocity autocorrelation function. Thus, the present research significantly extends capabilities of the CTRW formalism. Contribution to the Topical Issue "Continuous Time Random Walk Still Trendy: Fifty-year History, Current State and Outlook", edited by Ryszard Kutner and Jaume Masoliver.

  20. Intraindividual Stepping Reaction Time Variability Predicts Falls in Older Adults With Mild Cognitive Impairment

    OpenAIRE

    Bunce, D; Haynes, BI; Lord, SR; Gschwind, YJ; Kochan, NA; Reppermund, S; Brodaty, H; Sachdev, PS; Delbaere, K

    2017-01-01

    Background: Reaction time measures have considerable potential to aid neuropsychological assessment in a variety of health care settings. One such measure, the intraindividual reaction time variability (IIV), is of particular interest as it is thought to reflect neurobiological disturbance. IIV is associated with a variety of age-related neurological disorders, as well as gait impairment and future falls in older adults. However, although persons diagnosed with Mild Cognitive Impairment (MCI)...

  1. Assessment of radiopacity of restorative composite resins with various target distances and exposure times and a modified aluminum step wedge

    Energy Technology Data Exchange (ETDEWEB)

    Bejeh Mir, Arash Poorsattar [Dentistry Student Research Committee (DSRC), Dental Materials Research Center, Dentistry School, Babol University of Medical Sciences, Babol (Iran, Islamic Republic of); Bejeh Mir, Morvarid Poorsattar [Private Practice of Orthodontics, Montreal, Quebec (Canada)

    2012-09-15

    ANSI/ADA has established standards for adequate radiopacity. This study was aimed to assess the changes in radiopacity of composite resins according to various tube-target distances and exposure times. Five 1-mm thick samples of Filtek P60 and Clearfil composite resins were prepared and exposed with six tube-target distance/exposure time setups (i.e., 40 cm, 0.2 seconds; 30 cm, 0.2 seconds; 30 cm, 0.16 seconds, 30 cm, 0.12 seconds; 15 cm, 0.2 seconds; 15 cm, 0.12 seconds) performing at 70 kVp and 7 mA along with a 12-step aluminum stepwedge (1 mm incremental steps) using a PSP digital sensor. Thereafter, the radiopacities measured with Digora for Windows software 2.5 were converted to absorbencies (i.e., A=-log (1-G/255)), where A is the absorbency and G is the measured gray scale). Furthermore, the linear regression model of aluminum thickness and absorbency was developed and used to convert the radiopacity of dental materials to the equivalent aluminum thickness. In addition, all calculations were compared with those obtained from a modified 3-step stepwedge (i.e., using data for the 2nd, 5th, and 8th steps). The radiopacities of the composite resins differed significantly with various setups (p<0.001) and between the materials (p<0.001). The best predicted model was obtained for the 30 cm 0.2 seconds setup (R2=0.999). Data from the reduced modified stepwedge was remarkable and comparable with the 12-step stepwedge. Within the limits of the present study, our findings support that various setups might influence the radiopacity of dental materials on digital radiographs.

  2. Time-dependent restricted-active-space self-consistent eld theory: Formulation and application to laser-driven many-electron dynamics

    DEFF Research Database (Denmark)

    Miyagi, Haruhide; Madsen, Lars Bojer

    We have developed a new theoretical framework for time-dependent many-electron problems named time-dependent restricted-active-space self-consistent field (TD-RASSCF) theory. The theory generalizes the multicongurational time-dependent Hartree-Fock (MCTDHF) theory by truncating the expansion...

  3. Modelling of Sub-daily Hydrological Processes Using Daily Time-Step Models: A Distribution Function Approach to Temporal Scaling

    Science.gov (United States)

    Kandel, D. D.; Western, A. W.; Grayson, R. B.

    2004-12-01

    Mismatches in scale between the fundamental processes, the model and supporting data are a major limitation in hydrologic modelling. Surface runoff generation via infiltration excess and the process of soil erosion are fundamentally short time-scale phenomena and their average behaviour is mostly determined by the short time-scale peak intensities of rainfall. Ideally, these processes should be simulated using time-steps of the order of minutes to appropriately resolve the effect of rainfall intensity variations. However, sub-daily data support is often inadequate and the processes are usually simulated by calibrating daily (or even coarser) time-step models. Generally process descriptions are not modified but rather effective parameter values are used to account for the effect of temporal lumping, assuming that the effect of the scale mismatch can be counterbalanced by tuning the parameter values at the model time-step of interest. Often this results in parameter values that are difficult to interpret physically. A similar approach is often taken spatially. This is problematic as these processes generally operate or interact non-linearly. This indicates a need for better techniques to simulate sub-daily processes using daily time-step models while still using widely available daily information. A new method applicable to many rainfall-runoff-erosion models is presented. The method is based on temporal scaling using statistical distributions of rainfall intensity to represent sub-daily intensity variations in a daily time-step model. This allows the effect of short time-scale nonlinear processes to be captured while modelling at a daily time-step, which is often attractive due to the wide availability of daily forcing data. The approach relies on characterising the rainfall intensity variation within a day using a cumulative distribution function (cdf). This cdf is then modified by various linear and nonlinear processes typically represented in hydrological and

  4. Effect of time step size and turbulence model on the open water hydrodynamic performance prediction of contra-rotating propellers

    Science.gov (United States)

    Wang, Zhan-zhi; Xiong, Ying

    2013-04-01

    A growing interest has been devoted to the contra-rotating propellers (CRPs) due to their high propulsive efficiency, torque balance, low fuel consumption, low cavitations, low noise performance and low hull vibration. Compared with the single-screw system, it is more difficult for the open water performance prediction because forward and aft propellers interact with each other and generate a more complicated flow field around the CRPs system. The current work focuses on the open water performance prediction of contra-rotating propellers by RANS and sliding mesh method considering the effect of computational time step size and turbulence model. The validation study has been performed on two sets of contra-rotating propellers developed by David W Taylor Naval Ship R & D center. Compared with the experimental data, it shows that RANS with sliding mesh method and SST k-ω turbulence model has a good precision in the open water performance prediction of contra-rotating propellers, and small time step size can improve the level of accuracy for CRPs with the same blade number of forward and aft propellers, while a relatively large time step size is a better choice for CRPs with different blade numbers.

  5. Seven Steps to Heaven: Time and Tide in 21st Century Contemporary Music Higher Education

    Science.gov (United States)

    Mitchell, Annie K.

    2018-01-01

    Throughout the time of my teaching career, the tide has exposed changes in the nature of music, students and music education. This paper discusses teaching and learning in contemporary music at seven critical stages of 21st century music education: i) diverse types of undergraduate learners; ii) teaching traditional classical repertoire and skills…

  6. Time stepping free numerical solution of linear differential equations: Krylov subspace versus waveform relaxation

    NARCIS (Netherlands)

    Bochev, Mikhail A.; Oseledets, I.V.; Tyrtyshnikov, E.E.

    2013-01-01

    The aim of this paper is two-fold. First, we propose an efficient implementation of the continuous time waveform relaxation method based on block Krylov subspaces. Second, we compare this new implementation against Krylov subspace methods combined with the shift and invert technique.

  7. Local time stepping with the discontinuous Galerkin method for wave propagation in 3D heterogeneous media

    NARCIS (Netherlands)

    Minisini, S.; Zhebel, E.; Kononov, A.; Mulder, W.A.

    2013-01-01

    Modeling and imaging techniques for geophysics are extremely demanding in terms of computational resources. Seismic data attempt to resolve smaller scales and deeper targets in increasingly more complex geologic settings. Finite elements enable accurate simulation of time-dependent wave propagation

  8. Simultaneous bilateral stereotactic procedure for deep brain stimulation implants: a significant step for reducing operation time.

    Science.gov (United States)

    Fonoff, Erich Talamoni; Azevedo, Angelo; Angelos, Jairo Silva Dos; Martinez, Raquel Chacon Ruiz; Navarro, Jessie; Reis, Paul Rodrigo; Sepulveda, Miguel Ernesto San Martin; Cury, Rubens Gisbert; Ghilardi, Maria Gabriela Dos Santos; Teixeira, Manoel Jacobsen; Lopez, William Omar Contreras

    2016-07-01

    OBJECT Currently, bilateral procedures involve 2 sequential implants in each of the hemispheres. The present report demonstrates the feasibility of simultaneous bilateral procedures during the implantation of deep brain stimulation (DBS) leads. METHODS Fifty-seven patients with movement disorders underwent bilateral DBS implantation in the same study period. The authors compared the time required for the surgical implantation of deep brain electrodes in 2 randomly assigned groups. One group of 28 patients underwent traditional sequential electrode implantation, and the other 29 patients underwent simultaneous bilateral implantation. Clinical outcomes of the patients with Parkinson's disease (PD) who had undergone DBS implantation of the subthalamic nucleus using either of the 2 techniques were compared. RESULTS Overall, a reduction of 38.51% in total operating time for the simultaneous bilateral group (136.4 ± 20.93 minutes) as compared with that for the traditional consecutive approach (220.3 ± 27.58 minutes) was observed. Regarding clinical outcomes in the PD patients who underwent subthalamic nucleus DBS implantation, comparing the preoperative off-medication condition with the off-medication/on-stimulation condition 1 year after the surgery in both procedure groups, there was a mean 47.8% ± 9.5% improvement in the Unified Parkinson's Disease Rating Scale Part III (UPDRS-III) score in the simultaneous group, while the sequential group experienced 47.5% ± 15.8% improvement (p = 0.96). Moreover, a marked reduction in the levodopa-equivalent dose from preoperatively to postoperatively was similar in these 2 groups. The simultaneous bilateral procedure presented major advantages over the traditional sequential approach, with a shorter total operating time. CONCLUSIONS A simultaneous stereotactic approach significantly reduces the operation time in bilateral DBS procedures, resulting in decreased microrecording time, contributing to the optimization of functional

  9. Time Alignment as a Necessary Step in the Analysis of Sleep Probabilistic Curves

    Science.gov (United States)

    Rošt'áková, Zuzana; Rosipal, Roman

    2018-02-01

    Sleep can be characterised as a dynamic process that has a finite set of sleep stages during the night. The standard Rechtschaffen and Kales sleep model produces discrete representation of sleep and does not take into account its dynamic structure. In contrast, the continuous sleep representation provided by the probabilistic sleep model accounts for the dynamics of the sleep process. However, analysis of the sleep probabilistic curves is problematic when time misalignment is present. In this study, we highlight the necessity of curve synchronisation before further analysis. Original and in time aligned sleep probabilistic curves were transformed into a finite dimensional vector space, and their ability to predict subjects' age or daily measures is evaluated. We conclude that curve alignment significantly improves the prediction of the daily measures, especially in the case of the S2-related sleep states or slow wave sleep.

  10. The impact of weight classification on safety: timing steps to adapt to external constraints

    Science.gov (United States)

    Gill, S.V.

    2015-01-01

    Objectives: The purpose of the current study was to evaluate how weight classification influences safety by examining adults’ ability to meet a timing constraint: walking to the pace of an audio metronome. Methods: With a cross-sectional design, walking parameters were collected as 55 adults with normal (n=30) and overweight (n=25) body mass index scores walked to slow, normal, and fast audio metronome paces. Results: Between group comparisons showed that at the fast pace, those with overweight body mass index (BMI) had longer double limb support and stance times and slower cadences than the normal weight group (all psmetronome paces revealed that participants who were overweight had higher cadences at the slow and fast paces (all ps<0.05). Conclusions: Findings suggest that those with overweight BMI alter their gait to maintain biomechanical stability. Understanding how excess weight influences gait adaptation can inform interventions to improve safety for individuals with obesity. PMID:25730658

  11. Off-line real-time FTIR analysis of a process step in imipenem production

    Science.gov (United States)

    Boaz, Jhansi R.; Thomas, Scott M.; Meyerhoffer, Steven M.; Staskiewicz, Steven J.; Lynch, Joseph E.; Egan, Richard S.; Ellison, Dean K.

    1992-08-01

    We have developed an FT-IR method, using a Spectra-Tech Monit-IR 400 systems, to monitor off-line the completion of a reaction in real-time. The reaction is moisture-sensitive and analysis by more conventional methods (normal-phase HPLC) is difficult to reproduce. The FT-IR method is based on the shift of a diazo band when a conjugated beta-diketone is transformed into a silyl enol ether during the reaction. The reaction mixture is examined directly by IR and does not require sample workup. Data acquisition time is less than one minute. The method has been validated for specificity, precision and accuracy. The results obtained by the FT-IR method for known mixtures and in-process samples compare favorably with those from a normal-phase HPLC method.

  12. Effect of moisture and drying time on the bond strength of the one-step self-etching adhesive system

    Directory of Open Access Journals (Sweden)

    Yoon Lee

    2012-08-01

    Full Text Available Objectives To investigate the effect of dentin moisture degree and air-drying time on dentin-bond strength of two different one-step self-etching adhesive systems. Materials and Methods Twenty-four human third molars were used for microtensile bond strength testing of G-Bond and Clearfil S3 Bond. The dentin surface was either blot-dried or air-dried before applying these adhesive agents. After application of the adhesive agent, three different air drying times were evaluated: 1, 5, and 10 sec. Composite resin was build up to 4 mm thickness and light cured for 40 sec with 2 separate layers. Then the tooth was sectioned and trimmed to measure the microtensile bond strength using a universal testing machine. The measured bond strengths were analyzed with three-way ANOVA and regression analysis was done (p = 0.05. Results All three factors, materials, dentin wetness and air drying time, showed significant effect on the microtensile bond strength. Clearfil S3 Bond, dry dentin surface and 10 sec air drying time showed higher bond strength. Conclusions Within the limitation of this experiment, air drying time after the application of the one-step self-etching adhesive agent was the most significant factor affecting the bond strength, followed by the material difference and dentin moisture before applying the adhesive agent.

  13. Issues in measure-preserving three dimensional flow integrators: Self-adjointness, reversibility, and non-uniform time stepping

    International Nuclear Information System (INIS)

    Finn, John M.

    2015-01-01

    Properties of integration schemes for solenoidal fields in three dimensions are studied, with a focus on integrating magnetic field lines in a plasma using adaptive time stepping. It is shown that implicit midpoint (IM) and a scheme we call three-dimensional leapfrog (LF) can do a good job (in the sense of preserving KAM tori) of integrating fields that are reversible, or (for LF) have a “special divergence-free” (SDF) property. We review the notion of a self-adjoint scheme, showing that such schemes are at least second order accurate and can always be formed by composing an arbitrary scheme with its adjoint. We also review the concept of reversibility, showing that a reversible but not exactly volume-preserving scheme can lead to a fractal invariant measure in a chaotic region, although this property may not often be observable. We also show numerical results indicating that the IM and LF schemes can fail to preserve KAM tori when the reversibility property (and the SDF property for LF) of the field is broken. We discuss extensions to measure preserving flows, the integration of magnetic field lines in a plasma and the integration of rays for several plasma waves. The main new result of this paper relates to non-uniform time stepping for volume-preserving flows. We investigate two potential schemes, both based on the general method of Feng and Shang [Numer. Math. 71, 451 (1995)], in which the flow is integrated in split time steps, each Hamiltonian in two dimensions. The first scheme is an extension of the method of extended phase space, a well-proven method of symplectic integration with non-uniform time steps. This method is found not to work, and an explanation is given. The second method investigated is a method based on transformation to canonical variables for the two split-step Hamiltonian systems. This method, which is related to the method of non-canonical generating functions of Richardson and Finn [Plasma Phys. Controlled Fusion 54, 014004 (2012

  14. First steps towards real-time radiography at the NECTAR facility

    Science.gov (United States)

    Bücherl, T.; Wagner, F. M.; v. Gostomski, Ch. Lierse

    2009-06-01

    The beam tube SR10 at Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM II) provides an intense beam of fission neutrons for medical application (MEDAPP) and for radiography and tomography of technical and other objects (NECTAR). The high neutron flux of up to 9.8E+07 cm -2 s -1 (depending on filters and collimation) with a mean energy of about 1.9 MeV at the sample position at the NECTAR facility prompted an experimental feasibility study to investigate the potential for real-time (RT) radiography.

  15. First steps towards real-time radiography at the NECTAR facility

    International Nuclear Information System (INIS)

    Buecherl, T.; Wagner, F.M.; Lierse von Gostomski, Ch.

    2009-01-01

    The beam tube SR10 at Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM II) provides an intense beam of fission neutrons for medical application (MEDAPP) and for radiography and tomography of technical and other objects (NECTAR). The high neutron flux of up to 9.8E+07 cm -2 s -1 (depending on filters and collimation) with a mean energy of about 1.9 MeV at the sample position at the NECTAR facility prompted an experimental feasibility study to investigate the potential for real-time (RT) radiography.

  16. First steps towards real-time radiography at the NECTAR facility

    Energy Technology Data Exchange (ETDEWEB)

    Buecherl, T. [Lehrstuhl fuer Radiochemie (RCM), Technische Universitaet Muenchen (TUM) (Germany)], E-mail: thomas.buecherl@radiochemie.de; Wagner, F.M. [Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM II), Technische Universitaet Muenchen (Germany); Lierse von Gostomski, Ch. [Lehrstuhl fuer Radiochemie (RCM), Technische Universitaet Muenchen (TUM) (Germany)

    2009-06-21

    The beam tube SR10 at Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM II) provides an intense beam of fission neutrons for medical application (MEDAPP) and for radiography and tomography of technical and other objects (NECTAR). The high neutron flux of up to 9.8E+07 cm{sup -2} s{sup -1} (depending on filters and collimation) with a mean energy of about 1.9 MeV at the sample position at the NECTAR facility prompted an experimental feasibility study to investigate the potential for real-time (RT) radiography.

  17. A Novel Bioinspired Vision System: A Step toward Real-Time Human-Robot Interactions

    Directory of Open Access Journals (Sweden)

    Abdul Rahman Hafiz

    2011-01-01

    Full Text Available Building a human-like robot that could be involved in our daily lives is a dream of many scientists. Achieving a sophisticated robot's vision system, which can enhance the robot's real-time interaction ability with the human, is one of the main keys toward realizing such an autonomous robot. In this work, we are suggesting a bioinspired vision system that helps to develop an advanced human-robot interaction in an autonomous humanoid robot. First, we enhance the robot's vision accuracy online by applying a novel dynamic edge detection algorithm abstracted from the rules that the horizontal cells play in the mammalian retina. Second, in order to support the first algorithm, we improve the robot's tracking ability by designing a variant photoreceptors distribution corresponding to what exists in the human vision system. The experimental results verified the validity of the model. The robot could have a clear vision in real time and build a mental map that assisted it to be aware of the frontal users and to develop a positive interaction with them.

  18. PHISICS/RELAP5-3D Adaptive Time-Step Method Demonstrated for the HTTR LOFC#1 Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Robin Ivey [Idaho National Lab. (INL), Idaho Falls, ID (United States); Balestra, Paolo [Univ. of Rome (Italy); Strydom, Gerhard [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-05-01

    A collaborative effort between Japan Atomic Energy Agency (JAEA) and Idaho National Laboratory (INL) as part of the Civil Nuclear Energy Working Group is underway to model the high temperature engineering test reactor (HTTR) loss of forced cooling (LOFC) transient that was performed in December 2010. The coupled version of RELAP5-3D, a thermal fluids code, and PHISICS, a neutronics code, were used to model the transient. The focus of this report is to summarize the changes made to the PHISICS-RELAP5-3D code for implementing an adaptive time step methodology into the code for the first time, and to test it using the full HTTR PHISICS/RELAP5-3D model developed by JAEA and INL and the LOFC simulation. Various adaptive schemes are available based on flux or power convergence criteria that allow significantly larger time steps to be taken by the neutronics module. The report includes a description of the HTTR and the associated PHISICS/RELAP5-3D model test results as well as the University of Rome sub-contractor report documenting the adaptive time step theory and methodology implemented in PHISICS/RELAP5-3D. Two versions of the HTTR model were tested using 8 and 26 energy groups. It was found that most of the new adaptive methods lead to significant improvements in the LOFC simulation time required without significant accuracy penalties in the prediction of the fission power and the fuel temperature. In the best performing 8 group model scenarios, a LOFC simulation of 20 hours could be completed in real-time, or even less than real-time, compared with the previous version of the code that completed the same transient 3-8 times slower than real-time. A few of the user choice combinations between the methodologies available and the tolerance settings did however result in unacceptably high errors or insignificant gains in simulation time. The study is concluded with recommendations on which methods to use for this HTTR model. An important caveat is that these findings

  19. Time-step selection considerations in the analysis of reactor transients with DIF3D-K

    International Nuclear Information System (INIS)

    Taiwo, T.A.; Khalil, H.S.; Cahalan, J.E.; Morris, E.E.

    1993-01-01

    The DIF3D-K code solves the three-dimensional, time-dependent multigroup neutron diffusion equations by using a nodal approach for spatial discretization and either the theta method or one of three space-time factorization approaches for temporal integration of the nodal equations. The three space-time factorization options (namely, improved quasistatic, adiabatic, and conventional point kinetics) were implemented because of their potential efficiency advantage for the analysis of transients in which the flux shape changes more slowly than its amplitude. In this paper, we describe the implementation of DIF3D-K as the neutronics module within the SAS-HWR accident analysis code. We also describe the neuronic-related time-step selection algorithms and their influence on the accuracy and efficiency of the various solution options

  20. Time-step selection considerations in the analysis of reactor transients with DIF3D-K

    International Nuclear Information System (INIS)

    Taiwo, T.A.; Khalil, H.S.; Cahalan, J.E.; Morris, E.E.

    1993-01-01

    The DIF3D-K code solves the three-dimensional, time-dependent multigroup neutron diffusion equations by using a nodal approach for spatial discretization and either the theta method or one of three space-time factorization approaches for temporal integration of the nodal equations. The three space-time factorization options (namely, improved quasistatic, adiabatic and conventional point kinetics) were implemented because of their potential efficiency advantage for the analysis of transients in which the flux shape changes more slowly than its amplitude. Here we describe the implementation of DIF3D-K as the neutronics module within the SAS-HWR accident analysis code. We also describe the neutronics-related time step selection algorithms and their influence on the accuracy and efficiency of the various solution options

  1. Effect of increased exposure times on amount of residual monomer released from single-step self-etch adhesives.

    Science.gov (United States)

    Altunsoy, Mustafa; Botsali, Murat Selim; Tosun, Gonca; Yasar, Ahmet

    2015-10-16

    The aim of this study was to evaluate the effect of increased exposure times on the amount of residual Bis-GMA, TEGDMA, HEMA and UDMA released from single-step self-etch adhesive systems. Two adhesive systems were used. The adhesives were applied to bovine dentin surface according to the manufacturer's instructions and were polymerized using an LED curing unit for 10, 20 and 40 seconds (n = 5). After polymerization, the specimens were stored in 75% ethanol-water solution (6 mL). Residual monomers (Bis-GMA, TEGDMA, UDMA and HEMA) that were eluted from the adhesives (after 10 minutes, 1 hour, 1 day, 7 days and 30 days) were analyzed by high-performance liquid chromatography (HPLC). The data were analyzed using 1-way analysis of variance and Tukey HSD tests. Among the time periods, the highest amount of released residual monomers from adhesives was observed in the 10th minute. There were statistically significant differences regarding released Bis-GMA, UDMA, HEMA and TEGDMA between the adhesive systems (p<0.05). There were no significant differences among the 10, 20 and 40 second polymerization times according to their effect on residual monomer release from adhesives (p>0.05). Increasing the polymerization time did not have an effect on residual monomer release from single-step self-etch adhesives.

  2. In the time of significant generational diversity - surgical leadership must step up!

    Science.gov (United States)

    Money, Samuel R; O'Donnell, Mark E; Gray, Richard J

    2014-02-01

    The diverse attitudes and motivations of surgeons and surgical trainees within different age groups present an important challenge for surgical leaders and educators. These challenges to surgical leadership are not unique, and other industries have likewise needed to grapple with how best to manage these various age groups. The authors will herein explore management and leadership for surgeons in a time of age diversity, define generational variations within "Baby-Boomer", "Generation X" and "Generation Y" populations, and identify work ethos concepts amongst these three groups. The surgical community must understand and embrace these concepts in order to continue to attract a stellar pool of applicants from medical school. By not accepting the changing attitudes and motivations of young trainees and medical students, we may disenfranchise a high percentage of potential future surgeons. Surgical training programs will fill, but will they contain the highest quality trainees? Copyright © 2013 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.

  3. Unexpected perturbations training improves balance control and voluntary stepping times in older adults - a double blind randomized control trial.

    Science.gov (United States)

    Kurz, Ilan; Gimmon, Yoav; Shapiro, Amir; Debi, Ronen; Snir, Yoram; Melzer, Itshak

    2016-03-04

    Falls are common among elderly, most of them occur while slipping or tripping during walking. We aimed to explore whether a training program that incorporates unexpected loss of balance during walking able to improve risk factors for falls. In a double-blind randomized controlled trial 53 community dwelling older adults (age 80.1±5.6 years), were recruited and randomly allocated to an intervention group (n = 27) or a control group (n = 26). The intervention group received 24 training sessions over 3 months that included unexpected perturbation of balance exercises during treadmill walking. The control group performed treadmill walking with no perturbations. The primary outcome measures were the voluntary step execution times, traditional postural sway parameters and Stabilogram-Diffusion Analysis. The secondary outcome measures were the fall efficacy Scale (FES), self-reported late life function (LLFDI), and Performance-Oriented Mobility Assessment (POMA). Compared to control, participation in intervention program that includes unexpected loss of balance during walking led to faster Voluntary Step Execution Times under single (p = 0.002; effect size [ES] =0.75) and dual task (p = 0.003; [ES] = 0.89) conditions; intervention group subjects showed improvement in Short-term Effective diffusion coefficients in the mediolateral direction of the Stabilogram-Diffusion Analysis under eyes closed conditions (p = 0.012, [ES] = 0.92). Compared to control there were no significant changes in FES, LLFDI, and POMA. An intervention program that includes unexpected loss of balance during walking can improve voluntary stepping times and balance control, both previously reported as risk factors for falls. This however, did not transferred to a change self-reported function and FES. ClinicalTrials.gov NCT01439451 .

  4. Detection of Listeria monocytogenes in ready-to-eat food by Step One real-time polymerase chain reaction.

    Science.gov (United States)

    Pochop, Jaroslav; Kačániová, Miroslava; Hleba, Lukáš; Lopasovský, L'ubomír; Bobková, Alica; Zeleňáková, Lucia; Stričík, Michal

    2012-01-01

    The aim of this study was to follow contamination of ready-to-eat food with Listeria monocytogenes by using the Step One real time polymerase chain reaction (PCR). We used the PrepSEQ Rapid Spin Sample Preparation Kit for isolation of DNA and MicroSEQ® Listeria monocytogenes Detection Kit for the real-time PCR performance. In 30 samples of ready-to-eat milk and meat products without incubation we detected strains of Listeria monocytogenes in five samples (swabs). Internal positive control (IPC) was positive in all samples. Our results indicated that the real-time PCR assay developed in this study could sensitively detect Listeria monocytogenes in ready-to-eat food without incubation.

  5. Development and validation of a local time stepping-based PaSR solver for combustion and radiation modeling

    DEFF Research Database (Denmark)

    Pang, Kar Mun; Ivarsson, Anders; Haider, Sajjad

    2013-01-01

    In the current work, a local time stepping (LTS) solver for the modeling of combustion, radiative heat transfer and soot formation is developed and validated. This is achieved using an open source computational fluid dynamics code, OpenFOAM. Akin to the solver provided in default assembly i...... library in the edcSimpleFoam solver which was introduced during the 6th OpenFOAM workshop is modified and coupled with the current solver. One of the main amendments made is the integration of soot radiation submodel since this is significant in rich flames where soot particles are formed. The new solver...

  6. Fast Determination of Distribution-Connected PV Impacts Using a Variable Time-Step Quasi-Static Time-Series Approach: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Mather, Barry

    2017-08-24

    The increasing deployment of distribution-connected photovoltaic (DPV) systems requires utilities to complete complex interconnection studies. Relatively simple interconnection study methods worked well for low penetrations of photovoltaic systems, but more complicated quasi-static time-series (QSTS) analysis is required to make better interconnection decisions as DPV penetration levels increase. Tools and methods must be developed to support this. This paper presents a variable-time-step solver for QSTS analysis that significantly shortens the computational time and effort to complete a detailed analysis of the operation of a distribution circuit with many DPV systems. Specifically, it demonstrates that the proposed variable-time-step solver can reduce the required computational time by as much as 84% without introducing any important errors to metrics, such as the highest and lowest voltage occurring on the feeder, number of voltage regulator tap operations, and total amount of losses realized in the distribution circuit during a 1-yr period. Further improvement in computational speed is possible with the introduction of only modest errors in these metrics, such as a 91 percent reduction with less than 5 percent error when predicting voltage regulator operations.

  7. A simple test of choice stepping reaction time for assessing fall risk in people with multiple sclerosis.

    Science.gov (United States)

    Tijsma, Mylou; Vister, Eva; Hoang, Phu; Lord, Stephen R

    2017-03-01

    Purpose To determine (a) the discriminant validity for established fall risk factors and (b) the predictive validity for falls of a simple test of choice stepping reaction time (CSRT) in people with multiple sclerosis (MS). Method People with MS (n = 210, 21-74y) performed the CSRT, sensorimotor, balance and neuropsychological tests in a single session. They were then followed up for falls using monthly fall diaries for 6 months. Results The CSRT test had excellent discriminant validity with respect to established fall risk factors. Frequent fallers (≥3 falls) performed significantly worse in the CSRT test than non-frequent fallers (0-2 falls). With the odds of suffering frequent falls increasing 69% with each SD increase in CSRT (OR = 1.69, 95% CI: 1.27-2.26, p = falls in people with MS. This test may prove useful in documenting longitudinal changes in fall risk in relation to MS disease progression and effects of interventions. Implications for rehabilitation Good choice stepping reaction time (CSRT) is required for maintaining balance. A simple low-tech CSRT test has excellent discriminative and predictive validity in relation to falls in people with MS. This test may prove useful documenting longitudinal changes in fall risk in relation to MS disease progression and effects of interventions.

  8. Calibration and Evaluation of Different Estimation Models of Daily Solar Radiation in Seasonally and Annual Time Steps in Shiraz Region

    Directory of Open Access Journals (Sweden)

    Hamid Reza Fooladmand

    2017-06-01

    2006 to 2008 were used for calibrating fourteen estimated models of solar radiation in seasonally and annual time steps and the measured data of years 2009 and 2010 were used for evaluating the obtained results. The equations were used in this study divided into three groups contains: 1 The equations based on only sunshine hours. 2 The equations based on only air temperature. 3 The equations based on sunshine hours and air temperature together. On the other hand, statistical comparison must be done to select the best equation for estimating solar radiation in seasonally and annual time steps. For this purpose, in validation stage the combination of statistical equations and linear correlation was used, and then the value of mean square deviation (MSD was calculated to evaluate the different models for estimating solar radiation in mentioned time steps. Results and Discussion: The mean values of mean square deviation (MSD of fourteen models for estimating solar radiation were equal to 24.16, 20.42, 4.08 and 16.19 for spring to winter respectively, and 15.40 in annual time step. Therefore, the results showed that using the equations for autumn enjoyed high accuracy, however for other seasons had low accuracy. So, using the equations for annual time step were appropriate more than the equations for seasonally time steps. Also, the mean values of mean square deviation (MSD of the equations based on only sunshine hours, the equations based on only air temperature, and the equations based on the combination of sunshine hours and air temperature for estimating solar radiation were equal to 14.82, 17.40 and 14.88, respectively. Therefore, the results indicated that the models based on only air temperature were the worst conditions for estimating solar radiation in Shiraz region, and therefore, using the sunshine hours for estimating solar radiation is necessary. Conclusions: In this study for estimating solar radiation in seasonally and annual time steps in Shiraz region

  9. Effect of different air-drying time on the microleakage of single-step self-etch adhesives

    Directory of Open Access Journals (Sweden)

    Horieh Moosavi

    2013-05-01

    Full Text Available Objectives This study evaluated the effect of three different air-drying times on microleakage of three self-etch adhesive systems. Materials and Methods Class I cavities were prepared for 108 extracted sound human premolars. The teeth were divided into three main groups based on three different adhesives: Opti Bond All in One (OBAO, Clearfil S3 Bond (CSB, Bond Force (BF. Each main group divided into three subgroups regarding the air-drying time: without application of air stream, following the manufacturer's instruction, for 10 sec more than manufacturer's instruction. After completion of restorations, specimens were thermocycled and then connected to a fluid filtration system to evaluate microleakage. The data were statistically analyzed using two-way ANOVA and Tukey-test (α = 0.05. Results The microleakage of all adhesives decreased when the air-drying time increased from 0 sec to manufacturer's instruction (p < 0.001. The microleakage of BF reached its lowest values after increasing the drying time to 10 sec more than the manufacturer's instruction (p < 0.001. Microleakage of OBAO and CSB was significantly lower compared to BF in all three drying time (p < 0.001. Conclusions Increasing in air-drying time of adhesive layer in one-step self-etch adhesives caused reduction of microleakage, but the amount of this reduction may be dependent on the adhesive components of self-etch adhesives.

  10. How Are Child Restricted and Repetitive Behaviors Associated with Caregiver Stress over Time? A Parallel Process Multilevel Growth Model

    Science.gov (United States)

    Harrop, Clare; McBee, Matthew; Boyd, Brian A.

    2016-01-01

    The impact of raising a child with autism spectrum disorder (ASD) is frequently accompanied by elevated caregiver stress. Examining the variables that predict these elevated rates will help us understand how caregiver stress is impacted by and impacts child behaviors. This study explored how restricted and repetitive behaviors (RRBs) contributed…

  11. Small Steps: Preliminary effectiveness and feasibility of an incremental goal-setting intervention to reduce sitting time in older adults.

    Science.gov (United States)

    Lewis, L K; Rowlands, A V; Gardiner, P A; Standage, M; English, C; Olds, T

    2016-03-01

    This study aimed to evaluate the preliminary effectiveness and feasibility of a theory-informed program to reduce sitting time in older adults. Pre-experimental (pre-post) study. Thirty non-working adult (≥ 60 years) participants attended a one hour face-to-face intervention session and were guided through: a review of their sitting time; normative feedback on sitting time; and setting goals to reduce total sitting time and bouts of prolonged sitting. Participants chose six goals and integrated one per week incrementally for six weeks. Participants received weekly phone calls. Sitting time and bouts of prolonged sitting (≥ 30 min) were measured objectively for seven days (activPAL3c inclinometer) pre- and post-intervention. During these periods, a 24-h time recall instrument was administered by computer-assisted telephone interview. Participants completed a post-intervention project evaluation questionnaire. Paired t tests with sequential Bonferroni corrections and Cohen's d effect sizes were calculated for all outcomes. Twenty-seven participants completed the assessments (71.7 ± 6.5 years). Post-intervention, objectively-measured total sitting time was significantly reduced by 51.5 min per day (p=0.006; d=-0.58) and number of bouts of prolonged sitting by 0.8 per day (p=0.002; d=-0.70). Objectively-measured standing increased by 39 min per day (p=0.006; d=0.58). Participants self-reported spending 96 min less per day sitting (p<0.001; d=-0.77) and 32 min less per day watching television (p=0.005; d=-0.59). Participants were highly satisfied with the program. The 'Small Steps' program is a feasible and promising avenue for behavioral modification to reduce sitting time in older adults. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. Long-Time Plasma Membrane Imaging Based on a Two-Step Synergistic Cell Surface Modification Strategy.

    Science.gov (United States)

    Jia, Hao-Ran; Wang, Hong-Yin; Yu, Zhi-Wu; Chen, Zhan; Wu, Fu-Gen

    2016-03-16

    Long-time stable plasma membrane imaging is difficult due to the fast cellular internalization of fluorescent dyes and the quick detachment of the dyes from the membrane. In this study, we developed a two-step synergistic cell surface modification and labeling strategy to realize long-time plasma membrane imaging. Initially, a multisite plasma membrane anchoring reagent, glycol chitosan-10% PEG2000 cholesterol-10% biotin (abbreviated as "GC-Chol-Biotin"), was incubated with cells to modify the plasma membranes with biotin groups with the assistance of the membrane anchoring ability of cholesterol moieties. Fluorescein isothiocyanate (FITC)-conjugated avidin was then introduced to achieve the fluorescence-labeled plasma membranes based on the supramolecular recognition between biotin and avidin. This strategy achieved stable plasma membrane imaging for up to 8 h without substantial internalization of the dyes, and avoided the quick fluorescence loss caused by the detachment of dyes from plasma membranes. We have also demonstrated that the imaging performance of our staining strategy far surpassed that of current commercial plasma membrane imaging reagents such as DiD and CellMask. Furthermore, the photodynamic damage of plasma membranes caused by a photosensitizer, Chlorin e6 (Ce6), was tracked in real time for 5 h during continuous laser irradiation. Plasma membrane behaviors including cell shrinkage, membrane blebbing, and plasma membrane vesiculation could be dynamically recorded. Therefore, the imaging strategy developed in this work may provide a novel platform to investigate plasma membrane behaviors over a relatively long time period.

  13. Integration of FULLSWOF2D and PeanoClaw: Adaptivity and Local Time-Stepping for Complex Overland Flows

    KAUST Repository

    Unterweger, K.

    2015-01-01

    © Springer International Publishing Switzerland 2015. We propose to couple our adaptive mesh refinement software PeanoClaw with existing solvers for complex overland flows that are tailored to regular Cartesian meshes. This allows us to augment them with spatial adaptivity and local time-stepping without altering the computational kernels. FullSWOF2D—Full Shallow Water Overland Flows—here is our software of choice though all paradigms hold for other solvers as well.We validate our hybrid simulation software in an artificial test scenario before we provide results for a large-scale flooding scenario of the Mecca region. The latter demonstrates that our coupling approach enables the simulation of complex “real-world” scenarios.

  14. Third-order-accurate numerical methods for efficient, large time-step solutions of mixed linear and nonlinear problems

    Energy Technology Data Exchange (ETDEWEB)

    Cobb, J.W.

    1995-02-01

    There is an increasing need for more accurate numerical methods for large-scale nonlinear magneto-fluid turbulence calculations. These methods should not only increase the current state of the art in terms of accuracy, but should also continue to optimize other desired properties such as simplicity, minimized computation, minimized memory requirements, and robust stability. This includes the ability to stably solve stiff problems with long time-steps. This work discusses a general methodology for deriving higher-order numerical methods. It also discusses how the selection of various choices can affect the desired properties. The explicit discussion focuses on third-order Runge-Kutta methods, including general solutions and five examples. The study investigates the linear numerical analysis of these methods, including their accuracy, general stability, and stiff stability. Additional appendices discuss linear multistep methods, discuss directions for further work, and exhibit numerical analysis results for some other commonly used lower-order methods.

  15. A Novel Molten Salt Reactor Concept to Implement the Multi-Step Time-Scheduled Transmutation Strategy

    International Nuclear Information System (INIS)

    Csom, Gyula; Feher, Sandor; Szieberthj, Mate

    2002-01-01

    Nowadays the molten salt reactor (MSR) concept seems to revive as one of the most promising systems for the realization of transmutation. In the molten salt reactors and subcritical systems the fuel and material to be transmuted circulate dissolved in some molten salt. The main advantage of this reactor type is the possibility of the continuous feed and reprocessing of the fuel. In the present paper a novel molten salt reactor concept is introduced and its transmutation capabilities are studied. The goal is the development of a transmutation technique along with a device implementing it, which yield higher transmutation efficiencies than that of the known procedures and thus results in radioactive waste whose load on the environment is reduced both in magnitude and time length. The procedure is the multi-step time-scheduled transmutation, in which transformation is done in several consecutive steps of different neutron flux and spectrum. In the new MSR concept, named 'multi-region' MSR (MRMSR), the primary circuit is made up of a few separate loops, in which salt-fuel mixtures of different compositions are circulated. The loop sections constituting the core region are only neutronically and thermally coupled. This new concept makes possible the utilization of the spatial dependence of spectrum as well as the advantageous features of liquid fuel such as the possibility of continuous chemical processing etc. In order to compare a 'conventional' MSR and a proposed MRMSR in terms of efficiency, preliminary calculational results are shown. Further calculations in order to find the optimal implementation of this new concept and to emphasize its other advantageous features are going on. (authors)

  16. AN ACCURATE ORBITAL INTEGRATOR FOR THE RESTRICTED THREE-BODY PROBLEM AS A SPECIAL CASE OF THE DISCRETE-TIME GENERAL THREE-BODY PROBLEM

    International Nuclear Information System (INIS)

    Minesaki, Yukitaka

    2013-01-01

    For the restricted three-body problem, we propose an accurate orbital integration scheme that retains all conserved quantities of the two-body problem with two primaries and approximately preserves the Jacobi integral. The scheme is obtained by taking the limit as mass approaches zero in the discrete-time general three-body problem. For a long time interval, the proposed scheme precisely reproduces various periodic orbits that cannot be accurately computed by other generic integrators

  17. The ATP hydrolysis and phosphate release steps control the time course of force development in rabbit skeletal muscle.

    Science.gov (United States)

    Sleep, John; Irving, Malcolm; Burton, Kevin

    2005-03-15

    The time course of isometric force development following photolytic release of ATP in the presence of Ca(2+) was characterized in single skinned fibres from rabbit psoas muscle. Pre-photolysis force was minimized using apyrase to remove contaminating ATP and ADP. After the initial force rise induced by ATP release, a rapid shortening ramp terminated by a step stretch to the original length was imposed, and the time course of the subsequent force redevelopment was again characterized. Force development after ATP release was accurately described by a lag phase followed by one or two exponential components. At 20 degrees C, the lag was 5.6 +/- 0.4 ms (s.e.m., n = 11), and the force rise was well fitted by a single exponential with rate constant 71 +/- 4 s(-1). Force redevelopment after shortening-restretch began from about half the plateau force level, and its single-exponential rate constant was 68 +/- 3 s(-1), very similar to that following ATP release. When fibres were activated by the addition of Ca(2+) in ATP-containing solution, force developed more slowly, and the rate constant for force redevelopment following shortening-restretch reached a maximum value of 38 +/- 4 s(-1) (n = 6) after about 6 s of activation. This lower value may be associated with progressive sarcomere disorder at elevated temperature. Force development following ATP release was much slower at 5 degrees C than at 20 degrees C. The rate constant of a single-exponential fit to the force rise was 4.3 +/- 0.4 s(-1) (n = 22), and this was again similar to that after shortening-restretch in the same activation at this temperature, 3.8 +/- 0.2 s(-1). We conclude that force development after ATP release and shortening-restretch are controlled by the same steps in the actin-myosin ATPase cycle. The present results and much previous work on mechanical-chemical coupling in muscle can be explained by a kinetic scheme in which force is generated by a rapid conformational change bracketed by two

  18. Restricting daily time at pasture at low and high pasture allowance: effects on pasture intake and behavioral adaptation of lactating dairy cows.

    Science.gov (United States)

    Pérez-Ramírez, E; Peyraud, J L; Delagarde, R

    2009-07-01

    In pasture-based dairy systems, daily time at pasture is restricted during several periods of the year. The aim of this experiment was to evaluate the effect of restricting time at pasture on milk yield, pasture dry matter (DM) intake, and grazing behavior of dairy cows according to pasture allowance (PA), which partly defines pasture availability. The experiment was carried out in spring on strip-grazed perennial ryegrass pastures. The 6 treatments consisted of 3 durations of daily time at pasture [U: unrestricted day and night grazing (22 h at pasture); R9: 1 grazing session restricted to 9 h between the 2 milkings; R5: 2 grazing sessions of 2.75 h after each milking) compared at low and high PA (13 and 24 kg of DM/d per cow >5 cm, respectively). Eighteen mid-lactation Holstein dairy cows were used according to a 6 x 4 incomplete Latin square design replicated 3 times with four 14-d periods. Pasture DM intake was measured by the ytterbium-fecal index method and grazing behavior from portable devices. On average, restricting time at pasture from U to R (mean of R5 + R9) decreased pasture intake by 2.9 kg of DM, milk yield by 1.3 kg, and milk protein concentration by 0.11%, and increased milk fat concentration by 0.20%. Pasture intake and milk yield did not differ significantly between R9 and R5. The reduction of pasture intake and milk yield with decreasing time at pasture was greater at high compared with low PA. Grazing times were 536, 414, and 305 min, representing proportions of time spent grazing of 0.40, 0.77, and 0.93 for treatments U, R9, and R5, respectively. The reduction of grazing time with decreasing time at pasture was greater at high compared with low PA. Pasture intake rate greatly increased with decreasing time at pasture, but mainly on R5 (29.8, 31.6, and 42.1 g of DM/min for U, R9, and R5, respectively). The effect of time at pasture on pasture intake rate was unaffected by PA. In conclusion, the effect of restriction of time at pasture on

  19. Timing paradox of stepping and falls in ageing: not so quick and quick(er) on the trigger.

    Science.gov (United States)

    Rogers, Mark W; Mille, Marie-Laure

    2016-08-15

    Physiological and degenerative changes affecting human standing balance are major contributors to falls with ageing. During imbalance, stepping is a powerful protective action for preserving balance that may be voluntarily initiated in recognition of a balance threat, or be induced by an externally imposed mechanical or sensory perturbation. Paradoxically, with ageing and falls, initiation slowing of voluntary stepping is observed together with perturbation-induced steps that are triggered as fast as or faster than for younger adults. While age-associated changes in sensorimotor conduction, central neuronal processing and cognitive functions are linked to delayed voluntary stepping, alterations in the coupling of posture and locomotion may also prolong step triggering. It is less clear, however, how these factors may explain the accelerated triggering of induced stepping. We present a conceptual model that addresses this issue. For voluntary stepping, a disruption in the normal coupling between posture and locomotion may underlie step-triggering delays through suppression of the locomotion network based on an estimation of the evolving mechanical state conditions for stability. During induced stepping, accelerated step initiation may represent an event-triggering process whereby stepping is released according to the occurrence of a perturbation rather than to the specific sensorimotor information reflecting the evolving instability. In this case, errors in the parametric control of induced stepping and its effectiveness in stabilizing balance would be likely to occur. We further suggest that there is a residual adaptive capacity with ageing that could be exploited to improve paradoxical triggering and other changes in protective stepping to impact fall risk. © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.

  20. Rotor Cascade Shape Optimization with Unsteady Passing Wakes Using Implicit Dual-Time Stepping and a Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Eun Seok Lee

    2003-01-01

    Full Text Available An axial turbine rotor cascade-shape optimization with unsteady passing wakes was performed to obtain an improved aerodynamic performance using an unsteady flow, Reynolds-averaged Navier-Stokes equations solver that was based on explicit, finite difference; Runge-Kutta multistage time marching; and the diagonalized alternating direction implicit scheme. The code utilized Baldwin-Lomax algebraic and k-ε turbulence modeling. The full approximation storage multigrid method and preconditioning were implemented as iterative convergence-acceleration techniques. An implicit dual-time stepping method was incorporated in order to simulate the unsteady flow fields. The objective function was defined as minimization of total pressure loss and maximization of lift, while the mass flow rate was fixed during the optimization. The design variables were several geometric parameters characterizing airfoil leading edge, camber, stagger angle, and inter-row spacing. The genetic algorithm was used as an optimizer, and the penalty method was introduced for combining the constraints with the objective function. Each individual's objective function was computed simultaneously by using a 32-processor distributedmemory computer. The optimization results indicated that only minor improvements are possible in unsteady rotor/stator aerodynamics by varying these geometric parameters.

  1. Webinar Presentation: Environmental Exposures and Health Risks in California Child Care Facilities: First Steps to Improve Environmental Health where Children Spend Time

    Science.gov (United States)

    This presentation, Environmental Exposures and Health Risks in California Child Care Facilities: First Steps to Improve Environmental Health where Children Spend Time, was given at the NIEHS/EPA Children's Centers 2016 Webinar Series: Exposome.

  2. About 'restriction', 'justified' and 'necessary'

    DEFF Research Database (Denmark)

    Werlauff, Erik

    2016-01-01

    The article is an academic fairy tale about why and how all national corporate tax protection legislation should undergo a 3-part test to ensure its consistency with EU law. Each Member State introduce a compulsory 3-step test for each new (corporate) tax provision. The test is simple: (1) Does...... the tax provision constitute a restriction in the sense of EU law? (2) If the answer is yes: Is the restriction justified? (3) If the answer is yes: Is the restriction necessary?"...

  3. Restrictive cardiomyopathy

    Science.gov (United States)

    ... People with restrictive cardiomyopathy may be heart transplant candidates. The outlook depends on the cause of the ... www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. ...

  4. Biological effect of pulsed dose rate brachytherapy with stepping sources if short half-times of repair are present in tissues

    International Nuclear Information System (INIS)

    Fowler, Jack F.; Limbergen, Erik F.M. van

    1997-01-01

    therefore radiobiologically equivalent to the highest HDR. A stepping source of 1 curie carries a sphere of 'HDR' of radius 20 mm with it in its track through tissue. High ratios of PDR/LDR effect can be avoided by keeping dose per pulse below 1 Gy. Conclusions: Therefore, about 75% of the total dose is delivered at HDR in a PDR implant of moderate volume, reducing to 40% as the source decays from 1 to 0.3 curies. Even so, restricting the dose per pulse to 0.5 or 0.6 Gy should avoid ratios of increased effect larger than about 10%. It appears likely that PDR delivered by stepping source might behave more like HDR than LDR, especially for tissues with a substantial component of repair of very short T (1(2))

  5. Impact of Time-Restricted Feeding and Dawn-to-Sunset Fasting on Circadian Rhythm, Obesity, Metabolic Syndrome, and Nonalcoholic Fatty Liver Disease

    Directory of Open Access Journals (Sweden)

    Ayse L. Mindikoglu

    2017-01-01

    Full Text Available Obesity now affects millions of people and places them at risk of developing metabolic syndrome, nonalcoholic fatty liver disease (NAFLD, and even hepatocellular carcinoma. This rapidly emerging epidemic has led to a search for cost-effective methods to prevent the metabolic syndrome and NAFLD as well as the progression of NAFLD to cirrhosis and hepatocellular carcinoma. In murine models, time-restricted feeding resets the hepatic circadian clock and enhances transcription of key metabolic regulators of glucose and lipid homeostasis. Studies of the effect of dawn-to-sunset Ramadan fasting, which is akin to time-restricted feeding model, have also identified significant improvement in body mass index, serum lipid profiles, and oxidative stress parameters. Based on the findings of studies conducted on human subjects, dawn-to-sunset fasting has the potential to be a cost-effective intervention for obesity, metabolic syndrome, and NAFLD.

  6. Impact of Time-Restricted Feeding and Dawn-to-Sunset Fasting on Circadian Rhythm, Obesity, Metabolic Syndrome, and Nonalcoholic Fatty Liver Disease

    Science.gov (United States)

    Gagan, Sood K.

    2017-01-01

    Obesity now affects millions of people and places them at risk of developing metabolic syndrome, nonalcoholic fatty liver disease (NAFLD), and even hepatocellular carcinoma. This rapidly emerging epidemic has led to a search for cost-effective methods to prevent the metabolic syndrome and NAFLD as well as the progression of NAFLD to cirrhosis and hepatocellular carcinoma. In murine models, time-restricted feeding resets the hepatic circadian clock and enhances transcription of key metabolic regulators of glucose and lipid homeostasis. Studies of the effect of dawn-to-sunset Ramadan fasting, which is akin to time-restricted feeding model, have also identified significant improvement in body mass index, serum lipid profiles, and oxidative stress parameters. Based on the findings of studies conducted on human subjects, dawn-to-sunset fasting has the potential to be a cost-effective intervention for obesity, metabolic syndrome, and NAFLD. PMID:29348746

  7. Multiple time step molecular dynamics in the optimized isokinetic ensemble steered with the molecular theory of solvation: Accelerating with advanced extrapolation of effective solvation forces

    International Nuclear Information System (INIS)

    Omelyan, Igor; Kovalenko, Andriy

    2013-01-01

    We develop efficient handling of solvation forces in the multiscale method of multiple time step molecular dynamics (MTS-MD) of a biomolecule steered by the solvation free energy (effective solvation forces) obtained from the 3D-RISM-KH molecular theory of solvation (three-dimensional reference interaction site model complemented with the Kovalenko-Hirata closure approximation). To reduce the computational expenses, we calculate the effective solvation forces acting on the biomolecule by using advanced solvation force extrapolation (ASFE) at inner time steps while converging the 3D-RISM-KH integral equations only at large outer time steps. The idea of ASFE consists in developing a discrete non-Eckart rotational transformation of atomic coordinates that minimizes the distances between the atomic positions of the biomolecule at different time moments. The effective solvation forces for the biomolecule in a current conformation at an inner time step are then extrapolated in the transformed subspace of those at outer time steps by using a modified least square fit approach applied to a relatively small number of the best force-coordinate pairs. The latter are selected from an extended set collecting the effective solvation forces obtained from 3D-RISM-KH at outer time steps over a broad time interval. The MTS-MD integration with effective solvation forces obtained by converging 3D-RISM-KH at outer time steps and applying ASFE at inner time steps is stabilized by employing the optimized isokinetic Nosé-Hoover chain (OIN) ensemble. Compared to the previous extrapolation schemes used in combination with the Langevin thermostat, the ASFE approach substantially improves the accuracy of evaluation of effective solvation forces and in combination with the OIN thermostat enables a dramatic increase of outer time steps. We demonstrate on a fully flexible model of alanine dipeptide in aqueous solution that the MTS-MD/OIN/ASFE/3D-RISM-KH multiscale method of molecular dynamics

  8. Invited Commentary: Little Steps Lead to Huge Steps-It's Time to Make Physical Inactivity Our Number 1 Public Health Enemy.

    Science.gov (United States)

    Church, Timothy S

    2016-11-01

    The analysis plan and article in this issue of the Journal by Evenson et al. (Am J Epidemiol 2016;184(9):621-632) is well-conceived, thoughtfully conducted, and tightly written. The authors utilized the National Health and Nutrition Examination Survey data set to examine the association between accelerometer-measured physical activity level and mortality and found that meeting the 2013 federal Physical Activity Guidelines resulted in a 35% reduction in risk of mortality. The timing of these findings could not be better, given the ubiquitous nature of personal accelerometer devices. The masses are already equipped to routinely quantify their activity, and now we have the opportunity and responsibility to provide evidenced-based, tailored physical activity goals. We have evidenced-based physical activity guidelines, mass distribution of devices to track activity, and now scientific support indicating that meeting the physical activity goal, as assessed by these devices, has substantial health benefits. All of the pieces are in place to make physical inactivity a national priority, and we now have the opportunity to positively affect the health of millions of Americans. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. Multiplex, Rapid, and Sensitive Isothermal Detection of Nucleic-Acid Sequence by Endonuclease Restriction-Mediated Real-Time Multiple Cross Displacement Amplification.

    Science.gov (United States)

    Wang, Yi; Wang, Yan; Zhang, Lu; Liu, Dongxin; Luo, Lijuan; Li, Hua; Cao, Xiaolong; Liu, Kai; Xu, Jianguo; Ye, Changyun

    2016-01-01

    We have devised a novel isothermal amplification technology, termed endonuclease restriction-mediated real-time multiple cross displacement amplification (ET-MCDA), which facilitated multiplex, rapid, specific and sensitive detection of nucleic-acid sequences at a constant temperature. The ET-MCDA integrated multiple cross displacement amplification strategy, restriction endonuclease cleavage and real-time fluorescence detection technique. In the ET-MCDA system, the functional cross primer E-CP1 or E-CP2 was constructed by adding a short sequence at the 5' end of CP1 or CP2, respectively, and the new E-CP1 or E-CP2 primer was labeled at the 5' end with a fluorophore and in the middle with a dark quencher. The restriction endonuclease Nb.BsrDI specifically recognized the short sequence and digested the newly synthesized double-stranded terminal sequences (5' end short sequences and their complementary sequences), which released the quenching, resulting on a gain of fluorescence signal. Thus, the ET-MCDA allowed real-time detection of single or multiple targets in only a single reaction, and the positive results were observed in as short as 12 min, detecting down to 3.125 fg of genomic DNA per tube. Moreover, the analytical specificity and the practical application of the ET-MCDA were also successfully evaluated in this study. Here, we provided the details on the novel ET-MCDA technique and expounded the basic ET-MCDA amplification mechanism.

  10. Identification of Dobrava, Hantaan, Seoul, and Puumala viruses by one-step real-time RT-PCR.

    Science.gov (United States)

    Aitichou, Mohamed; Saleh, Sharron S; McElroy, Anita K; Schmaljohn, C; Ibrahim, M Sofi

    2005-03-01

    We developed four assays for specifically identifying Dobrava (DOB), Hantaan (HTN), Puumala (PUU), and Seoul (SEO) viruses. The assays are based on the real-time one-step reverse transcriptase polymerase chain reaction (RT-PCR) with the small segment used as the target sequence. The detection limits of DOB, HTN, PUU, and SEO assays were 25, 25, 25, and 12.5 plaque-forming units, respectively. The assays were evaluated in blinded experiments, each with 100 samples that contained Andes, Black Creek Canal, Crimean-Congo hemorrhagic fever, Rift Valley fever and Sin Nombre viruses in addition to DOB, HTN, PUU and SEO viruses. The sensitivity levels of the DOB, HTN, PUU, and SEO assays were 98%, 96%, 92% and 94%, respectively. The specificity of DOB, HTN and SEO assays was 100% and the specificity of the PUU assay was 98%. Because of the high levels of sensitivity, specificity, and reproducibility, we believe that these assays can be useful for diagnosing and differentiating these four Old-World hantaviruses.

  11. A two-step real-time PCR assay for quantitation and genotyping of human parvovirus 4.

    Science.gov (United States)

    Väisänen, E; Lahtinen, A; Eis-Hübinger, A M; Lappalainen, M; Hedman, K; Söderlund-Venermo, M

    2014-01-01

    Human parvovirus 4 (PARV4) of the family Parvoviridae was discovered in a plasma sample of a patient with an undiagnosed acute infection in 2005. Currently, three PARV4 genotypes have been identified, however, with an unknown clinical significance. Interestingly, these genotypes seem to differ in epidemiology. In Northern Europe, USA and Asia, genotypes 1 and 2 have been found to occur mainly in persons with a history of injecting drug use or other parenteral exposure. In contrast, genotype 3 appears to be endemic in sub-Saharan Africa, where it infects children and adults without such risk behaviour. In this study, a novel straightforward and cost-efficient molecular assay for both quantitation and genotyping of PARV4 DNA was developed. The two-step method first applies a single-probe pan-PARV4 qPCR for screening and quantitation of this relatively rare virus, and subsequently, only the positive samples undergo a real-time PCR-based multi-probe genotyping. The new qPCR-GT method is highly sensitive and specific regardless of the genotype, and thus being suitable for studying the clinical impact and occurrence of the different PARV4 genotypes. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Potentials and Limitations of Real-Time Elastography for Prostate Cancer Detection: A Whole-Mount Step Section Analysis

    Directory of Open Access Journals (Sweden)

    Daniel Junker

    2012-01-01

    Full Text Available Objectives. To evaluate prostate cancer (PCa detection rates of real-time elastography (RTE in dependence of tumor size, tumor volume, localization and histological type. Materials and Methods. Thirdy-nine patients with biopsy proven PCa underwent RTE before radical prostatectomy (RPE to assess prostate tissue elasticity, and hard lesions were considered suspicious for PCa. After RPE, the prostates were prepared as whole-mount step sections and were compared with imaging findings for analyzing PCa detection rates. Results. RTE detected 6/62 cancer lesions with a maximum diameter of 0–5 mm (9.7%, 10/37 with a maximum diameter of 6–10 mm (27%, 24/34 with a maximum diameter of 11–20 20 mm (70.6%, 14/14 with a maximum diameter of >20 mm (100% and 40/48 with a volume ≥0.2 cm3 (83.3%. Regarding cancer lesions with a volume ≥ 0.2 cm³ there was a significant difference in PCa detection rates between Gleason scores with predominant Gleason pattern 3 compared to those with predominant Gleason pattern 4 or 5 (75% versus 100%; P=0.028. Conclusions. RTE is able to detect PCa of significant tumor volume and of predominant Gleason pattern 4 or 5 with high confidence, but is of limited value in the detection of small cancer lesions.

  13. Effects of dietary selenium supply and timing of nutrient restriction during gestation on maternal growth and body composition of pregnant adolescent ewes.

    Science.gov (United States)

    Carlson, D B; Reed, J J; Borowicz, P P; Taylor, J B; Reynolds, L P; Neville, T L; Redmer, D A; Vonnahme, K A; Caton, J S

    2009-02-01

    with ASe. These data indicate that increased dietary Se affected whole-body and organ growth of pregnant ewes, but the results differed depending on the plane of nutrition. In addition, the timing and duration of nutrient restriction relative to stage of pregnancy affected visceral organ mass in a markedly different fashion.

  14. First-time whole blood donation: A critical step for donor safety and retention on first three donations.

    Science.gov (United States)

    Gillet, P; Rapaille, A; Benoît, A; Ceinos, M; Bertrand, O; de Bouyalsky, I; Govaerts, B; Lambermont, M

    2015-01-01

    Whole blood donation is generally safe although vasovagal reactions can occur (approximately 1%). Risk factors are well known and prevention measures are shown as efficient. This study evaluates the impact of the donor's retention in relation to the occurrence of vasovagal reaction for the first three blood donations. Our study of data collected over three years evaluated the impact of classical risk factors and provided a model including the best combination of covariates predicting VVR. The impact of a reaction at first donation on return rate and complication until the third donation was evaluated. Our data (523,471 donations) confirmed the classical risk factors (gender, age, donor status and relative blood volume). After stepwise variable selection, donor status, relative blood volume and their interaction were the only remaining covariates in the model. Of 33,279 first-time donors monitored over a period of at least 15 months, the first three donations were followed. Data emphasised the impact of complication at first donation. The return rate for a second donation was reduced and the risk of vasovagal reaction was increased at least until the third donation. First-time donation is a crucial step in the donors' career. Donors who experienced a reaction at their first donation have a lower return rate for a second donation and a higher risk of vasovagal reaction at least until the third donation. Prevention measures have to be processed to improve donor retention and provide blood banks with adequate blood supply. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  15. Step training improves reaction time, gait and balance and reduces falls in older people: a systematic review and meta-analysis.

    Science.gov (United States)

    Okubo, Yoshiro; Schoene, Daniel; Lord, Stephen R

    2017-04-01

    To examine the effects of stepping interventions on fall risk factors and fall incidence in older people. Electronic databases (PubMed, EMBASE, CINAHL, Cochrane, CENTRAL) and reference lists of included articles from inception to March 2015. Randomised (RCT) or clinical controlled trials (CCT) of volitional and reactive stepping interventions that included older (minimum age 60) people providing data on falls or fall risk factors. Meta-analyses of seven RCTs (n=660) showed that the stepping interventions significantly reduced the rate of falls (rate ratio=0.48, 95% CI 0.36 to 0.65, prisk ratio=0.51, 95% CI 0.38 to 0.68, pfalls and proportion of fallers. A meta-analysis of two RCTs (n=62) showed that stepping interventions significantly reduced laboratory-induced falls, and meta-analysis findings of up to five RCTs and CCTs (n=36-416) revealed that stepping interventions significantly improved simple and choice stepping reaction time, single leg stance, timed up and go performance (pfalls among older adults by approximately 50%. This clinically significant reduction may be due to improvements in reaction time, gait, balance and balance recovery but not in strength. Further high-quality studies aimed at maximising the effectiveness and feasibility of stepping interventions are required. CRD42015017357. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  16. Generalized Runge-Kutta method for two- and three-dimensional space-time diffusion equations with a variable time step

    International Nuclear Information System (INIS)

    Aboanber, A.E.; Hamada, Y.M.

    2008-01-01

    An extensive knowledge of the spatial power distribution is required for the design and analysis of different types of current-generation reactors, and that requires the development of more sophisticated theoretical methods. Therefore, the need to develop new methods for multidimensional transient reactor analysis still exists. The objective of this paper is to develop a computationally efficient numerical method for solving the multigroup, multidimensional, static and transient neutron diffusion kinetics equations. A generalized Runge-Kutta method has been developed for the numerical integration of the stiff space-time diffusion equations. The method is fourth-order accurate, using an embedded third-order solution to arrive at an estimate of the truncation error for automatic time step control. In addition, the A(α)-stability properties of the method are investigated. The analyses of two- and three-dimensional benchmark problems as well as static and transient problems, demonstrate that very accurate solutions can be obtained with assembly-sized spatial meshes. Preliminary numerical evaluations using two- and three-dimensional finite difference codes showed that the presented generalized Runge-Kutta method is highly accurate and efficient when compared with other optimized iterative numerical and conventional finite difference methods

  17. Age-related differences in lower-limb force-time relation during the push-off in rapid voluntary stepping.

    Science.gov (United States)

    Melzer, I; Krasovsky, T; Oddsson, L I E; Liebermann, D G

    2010-12-01

    This study investigated the force-time relationship during the push-off stage of a rapid voluntary step in young and older healthy adults, to study the assumption that when balance is lost a quick step may preserve stability. The ability to achieve peak propulsive force within a short time is critical for the performance of such a quick powerful step. We hypothesized that older adults would achieve peak force and power in significantly longer times compared to young people, particularly during the push-off preparatory phase. Fifteen young and 15 older volunteers performed rapid forward steps while standing on a force platform. Absolute anteroposterior and body weight normalized vertical forces during the push-off in the preparation and swing phases were used to determine time to peak and peak force, and step power. Two-way analyses of variance ('Group' [young-older] by 'Phase' [preparation-swing]) were used to assess our hypothesis (P ≤ 0.05). Older people exerted lower peak forces (anteroposterior and vertical) than young adults, but not necessarily lower peak power. More significantly, they showed a longer time to peak force, particularly in the vertical direction during the preparation phase. Older adults generate propulsive forces slowly and reach lower magnitudes, mainly during step preparation. The time to achieve a peak force and power, rather than its actual magnitude, may account for failures in quickly performing a preventive action. Such delay may be associated with the inability to react and recruit muscles quickly. Thus, training elderly to step fast in response to relevant cues may be beneficial in the prevention of falls. Copyright © 2010 Elsevier Ltd. All rights reserved.

  18. Canadian children's and youth's pedometer-determined steps/day, parent-reported TV watching time, and overweight/obesity: The CANPLAY Surveillance Study

    Directory of Open Access Journals (Sweden)

    Craig Cora L

    2011-06-01

    Full Text Available Abstract Background This study examines associations between pedometer-determined steps/day and parent-reported child's Body Mass Index (BMI and time typically spent watching television between school and dinner. Methods Young people (aged 5-19 years were recruited through their parents by random digit dialling and mailed a data collection package. Information on height and weight and time spent watching television between school and dinner on a typical school day was collected from parents. In total, 5949 boys and 5709 girls reported daily steps. BMI was categorized as overweight or obese using Cole's cut points. Participants wore pedometers for 7 days and logged daily steps. The odds of being overweight and obese by steps/day and parent-reported time spent television watching were estimated using logistic regression for complex samples. Results Girls had a lower median steps/day (10682 versus 11059 for boys and also a narrower variation in steps/day (interquartile range, 4410 versus 5309 for boys. 11% of children aged 5-19 years were classified as obese; 17% of boys and girls were overweight. Both boys and girls watched, on average, Discussion Television viewing is the more prominent factor in terms of predicting overweight, and it contributes to obesity, but steps/day attenuates the association between television viewing and obesity, and therefore can be considered protective against obesity. In addition to replacing opportunities for active alternative behaviours, exposure to television might also impact body weight by promoting excess energy intake. Conclusions In this large nationally representative sample, pedometer-determined steps/day was associated with reduced odds of being obese (but not overweight whereas each parent-reported hour spent watching television between school and dinner increased the odds of both overweight and obesity.

  19. Multiplex, rapid and sensitive isothermal detection of nucleic-acid sequence by endonuclease restriction-mediated real-time multiple cross displacement amplification

    Directory of Open Access Journals (Sweden)

    Yi eWang

    2016-05-01

    Full Text Available We have devised a novel isothermal amplification technology, termed endonuclease restriction-mediated real-time multiple cross displacement amplification (ET-MCDA, which facilitated multiplex, rapid, specific and sensitive detection of nucleic-acid sequences at a constant temperature. The ET-MCDA integrated multiple cross displacement amplification strategy, restriction endonuclease cleavage and real-time fluorescence detection technique. In the ET-MCDA system, the functional cross primer E-CP1 or E-CP2 was constructed by adding a short sequence at the 5’ end of CP1 or CP2, respectively, and the new E-CP1 or E-CP2 primer was labelled at the 5’ end with a fluorophore and in the middle with a dark quencher. The restriction endonuclease Nb.BsrDI specifically recognized the short sequence and digested the newly synthesized double-stranded terminal sequences (5’ end short sequences and their complementary sequences, which released the quenching, resulting on a gain of fluorescence signal. Thus, the ET-MCDA allowed real-time detection of single or multiple targets in only a single reaction, and the positive results were observed in as short as 12 minutes, detecting down to 3.125 fg of genomic DNA per tube. Moreover, the analytical specificity and the practical application of the ET-MCDA were also successfully evaluated in this study. Here we provided the details on the novel ET-MCDA technique and expounded the basic ET-MCDA amplification mechanism.

  20. ChromAlign: A two-step algorithmic procedure for time alignment of three-dimensional LC-MS chromatographic surfaces.

    Science.gov (United States)

    Sadygov, Rovshan G; Maroto, Fernando Martin; Hühmer, Andreas F R

    2006-12-15

    We present an algorithmic approach to align three-dimensional chromatographic surfaces of LC-MS data of complex mixture samples. The approach consists of two steps. In the first step, we prealign chromatographic profiles: two-dimensional projections of chromatographic surfaces. This is accomplished by correlation analysis using fast Fourier transforms. In this step, a temporal offset that maximizes the overlap and dot product between two chromatographic profiles is determined. In the second step, the algorithm generates correlation matrix elements between full mass scans of the reference and sample chromatographic surfaces. The temporal offset from the first step indicates a range of the mass scans that are possibly correlated, then the correlation matrix is calculated only for these mass scans. The correlation matrix carries information on highly correlated scans, but it does not itself determine the scan or time alignment. Alignment is determined as a path in the correlation matrix that maximizes the sum of the correlation matrix elements. The computational complexity of the optimal path generation problem is reduced by the use of dynamic programming. The program produces time-aligned surfaces. The use of the temporal offset from the first step in the second step reduces the computation time for generating the correlation matrix and speeds up the process. The algorithm has been implemented in a program, ChromAlign, developed in C++ language for the .NET2 environment in WINDOWS XP. In this work, we demonstrate the applications of ChromAlign to alignment of LC-MS surfaces of several datasets: a mixture of known proteins, samples from digests of surface proteins of T-cells, and samples prepared from digests of cerebrospinal fluid. ChromAlign accurately aligns the LC-MS surfaces we studied. In these examples, we discuss various aspects of the alignment by ChromAlign, such as constant time axis shifts and warping of chromatographic surfaces.

  1. A general formulation of discrete-time quantum mechanics: Restrictions on the action and the relation of unitarity to the existence theorem for initial-value problems

    International Nuclear Information System (INIS)

    Khorrami, M.

    1995-01-01

    A general formulation for discrete-time quantum mechanics, based on Feynman's method in ordinary quantum mechanics, is presented. It is shown that the ambiguities present in ordinary quantum mechanics (due to noncommutativity of the operators), are no longer present here. Then the criteria for the unitarity of the evolution operator are examined. It is shown that the unitarity of the evolution operator puts restrictions on the form of the action, and also implies the existence of a solution for the classical initial-value problem. 13 refs

  2. Molecular analysis of Leptospira spp. isolated from humans by restriction fragment length polymorphism, real-time PCR and pulsed-field gel electrophoresis.

    Science.gov (United States)

    Turk, Nenad; Milas, Zoran; Mojcec, Vesna; Ruzic-Sabljic, Eva; Staresina, Vilim; Stritof, Zrinka; Habus, Josipa; Postic, Daniele

    2009-11-01

    A total of 17 Leptospira clinical strains isolated from humans in Croatia were serologically and genetically analysed. For serovar identification, the microscopic agglutination test (MAT) and pulsed-field gel electrophoresis (PFGE) were used. To identify isolates on genomic species level, PCR-based restriction fragment length polymorphism (RFLP) and real-time PCR were performed. MAT revealed the following serogroup affinities: Grippotyphosa (seven isolates), Icterohaemorrhagiae (eight isolates) and Javanica (two isolates). RFLP of PCR products from a 331-bp-long fragment of rrs (16S rRNA gene) digested with endonucleases MnlI and DdeI and real-time PCR revealed three Leptospira genomic species. Grippotyphosa isolates belonged to Leptospira kirschneri, Icterohaemorrhagiae isolates to Leptospira interrogans and Javanica isolates to Leptospira borgpetersenii. Genomic DNA from 17 leptospiral isolates was digested with NotI and SgrAI restriction enzymes and analysed by PFGE. Results showed that seven isolates have the same binding pattern to serovar Grippotyphosa, eight isolates to serovar Icterohaemorrhagiae and two isolates to serovar Poi. Results demonstrate the diversity of leptospires circulating in Croatia. We point out the usefulness of a combination of PFGE, RFLP and real-time PCR as appropriate molecular methods in molecular analysis of leptospires.

  3. Evaluation of the Usefulness of Restricted Respiratory Period at the Time of Radiotherapy for Non-Small Cell Lung Cancer Patient

    Energy Technology Data Exchange (ETDEWEB)

    Park, So Yeon; Ahn, Jong Ho; Kim, Yung Il; Kim, Jin Man; Choi, Byung Ki; Pyo, Hong Ryul; Song, Ki Won [Dept. of Radiation Oncology, Samsung Medical Center, Seoul (Korea, Republic of); Suh, Jung Min [Dept. of Radiological Science, Daewon University Colloge, Jecheon (Korea, Republic of)

    2012-09-15

    It is essential to minimize the movement of tumor due to respiratory movement at the time of respiration controlled radiotherapy of non-small cell lung cancer patient. Accordingly, this Study aims to evaluate the usefulness of restricted respiratory period by comparing and analyzing the treatment plans that apply free and restricted respiration period respectively. After having conducted training on 9 non-small cell lung cancer patients (tumor n=10) from April to December 2011 by using 'signal monitored-breathing (guided- breathing)' method for the 'free respiratory period' measured on the basis of the regular respiratory period of the patents and 'restricted respiratory period' that was intentionally reduced, total of 10 CT images for each of the respiration phases were acquired by carrying out 4D CT for treatment planning purpose by using RPM and 4-dimensional computed tomography simulator. Visual gross tumor volume (GTV) and internal target volume (ITV) that each of the observer 1 and observer 2 has set were measured and compared on the CT image of each respiratory interval. Moreover, the amplitude of movement of tumor was measured by measuring the center of mass (COM) at the phase of 0% which is the end-inspiration (EI) and at the phase of 50% which is the end-exhalation (EE). In addition, both observers established treatment plan that applied the 2 respiratory periods, and mean dose to normal lung (MDTNL) was compared and analyzed through dose-volume histogram (DVH). Moreover, normal tissue complication probability (NTCP) of the normal lung volume was compared by using dose-volume histogram analysis program (DVH analyzer v.1) and statistical analysis was performed in order to carry out quantitative evaluation of the measured data. As the result of the analysis of the treatment plan that applied the 'restricted respiratory period' of the observer 1 and observer 2, there was reduction rate of 38.75% in the 3-dimensional

  4. Evaluation of the Usefulness of Restricted Respiratory Period at the Time of Radiotherapy for Non-Small Cell Lung Cancer Patient

    International Nuclear Information System (INIS)

    Park, So Yeon; Ahn, Jong Ho; Kim, Yung Il; Kim, Jin Man; Choi, Byung Ki; Pyo, Hong Ryul; Song, Ki Won; Suh, Jung Min

    2012-01-01

    It is essential to minimize the movement of tumor due to respiratory movement at the time of respiration controlled radiotherapy of non-small cell lung cancer patient. Accordingly, this Study aims to evaluate the usefulness of restricted respiratory period by comparing and analyzing the treatment plans that apply free and restricted respiration period respectively. After having conducted training on 9 non-small cell lung cancer patients (tumor n=10) from April to December 2011 by using 'signal monitored-breathing (guided- breathing)' method for the 'free respiratory period' measured on the basis of the regular respiratory period of the patents and 'restricted respiratory period' that was intentionally reduced, total of 10 CT images for each of the respiration phases were acquired by carrying out 4D CT for treatment planning purpose by using RPM and 4-dimensional computed tomography simulator. Visual gross tumor volume (GTV) and internal target volume (ITV) that each of the observer 1 and observer 2 has set were measured and compared on the CT image of each respiratory interval. Moreover, the amplitude of movement of tumor was measured by measuring the center of mass (COM) at the phase of 0% which is the end-inspiration (EI) and at the phase of 50% which is the end-exhalation (EE). In addition, both observers established treatment plan that applied the 2 respiratory periods, and mean dose to normal lung (MDTNL) was compared and analyzed through dose-volume histogram (DVH). Moreover, normal tissue complication probability (NTCP) of the normal lung volume was compared by using dose-volume histogram analysis program (DVH analyzer v.1) and statistical analysis was performed in order to carry out quantitative evaluation of the measured data. As the result of the analysis of the treatment plan that applied the 'restricted respiratory period' of the observer 1 and observer 2, there was reduction rate of 38.75% in the 3-dimensional direction movement of the tumor in

  5. Multiple-step fault estimation for interval type-II T-S fuzzy system of hypersonic vehicle with time-varying elevator faults

    Directory of Open Access Journals (Sweden)

    Jin Wang

    2017-03-01

    Full Text Available This article proposes a multiple-step fault estimation algorithm for hypersonic flight vehicles that uses an interval type-II Takagi–Sugeno fuzzy model. An interval type-II Takagi–Sugeno fuzzy model is developed to approximate the nonlinear dynamic system and handle the parameter uncertainties of hypersonic firstly. Then, a multiple-step time-varying additive fault estimation algorithm is designed to estimate time-varying additive elevator fault of hypersonic flight vehicles. Finally, the simulation is conducted in both aspects of modeling and fault estimation; the validity and availability of such method are verified by a series of the comparison of numerical simulation results.

  6. Complex analyses on clinical information systems using restricted natural language querying to resolve time-event dependencies.

    Science.gov (United States)

    Safari, Leila; Patrick, Jon D

    2018-06-01

    This paper reports on a generic framework to provide clinicians with the ability to conduct complex analyses on elaborate research topics using cascaded queries to resolve internal time-event dependencies in the research questions, as an extension to the proposed Clinical Data Analytics Language (CliniDAL). A cascaded query model is proposed to resolve internal time-event dependencies in the queries which can have up to five levels of criteria starting with a query to define subjects to be admitted into a study, followed by a query to define the time span of the experiment. Three more cascaded queries can be required to define control groups, control variables and output variables which all together simulate a real scientific experiment. According to the complexity of the research questions, the cascaded query model has the flexibility of merging some lower level queries for simple research questions or adding a nested query to each level to compose more complex queries. Three different scenarios (one of them contains two studies) are described and used for evaluation of the proposed solution. CliniDAL's complex analyses solution enables answering complex queries with time-event dependencies at most in a few hours which manually would take many days. An evaluation of results of the research studies based on the comparison between CliniDAL and SQL solutions reveals high usability and efficiency of CliniDAL's solution. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. Comparison of time-restricted and ad libitum self-feeding on the growth, feeding behavior and daily digestive enzyme profiles of Atlantic salmon

    Science.gov (United States)

    Shi, Ce; Liu, Ying; Yi, Mengmeng; Zheng, Jimeng; Tian, Huiqin; Du, Yishuai; Li, Xian; Sun, Guoxiang

    2017-07-01

    Although it has been hypothesized that a predictable feeding regime in animals allows physiological variables to be adjusted to maximize nutrient utilization and, hence, better growth performance, the assumption has rarely been tested. This study compares the effects of time-restricted versus free access self-feeding on the growth, feeding behavior and daily digestive enzyme rhythms of Atlantic salmon ( Salmo salar). In an experiment that lasted 6 weeks, fish (109.9 g) were divided into two groups: group 1 had free access to a self-feeder (FA); group 2 received three meals per day (2 h per meal) at dawn, midday and dusk via a time-restricted self-feeder (TR). At the end of the experiment, the fish were sampled every 3 h over a 24-h period. The results showed that the TR fish quickly synchronized their feeding behavior to the feeding window and their blood glucose showed a significant postprandial increase, while FA fish displayed no statistically significant rhythms ( P>0.05). Pepsin activity of TR fish also showed a significant daily rhythm ( P0.05). In conclusion, the study failed to confirm a link between the entrainment of daily digestive enzyme profiles and growth performance, with the TR group showing comparatively poor blood glucose regulation.

  8. Characterization of olive oil volatiles by multi-step direct thermal desorption-comprehensive gas chromatography-time-of-flight mass spectrometry using a programmed temperature vaporizing injector

    NARCIS (Netherlands)

    de Koning, S.; Kaal, E.; Janssen, H.-G.; van Platerink, C.; Brinkman, U.A.Th.

    2008-01-01

    The feasibility of a versatile system for multi-step direct thermal desorption (DTD) coupled to comprehensive gas chromatography (GC × GC) with time-of-flight mass spectrometric (TOF-MS) detection is studied. As an application the system is used for the characterization of fresh versus aged olive

  9. Physiological and cognitive mediators for the association between self-reported depressed mood and impaired choice stepping reaction time in older people.

    NARCIS (Netherlands)

    Kvelde, T.; Pijnappels, M.A.G.M.; Delbaere, K.; Close, J.C.; Lord, S.R.

    2010-01-01

    Background. The aim of the study was to use path analysis to test a theoretical model proposing that the relationship between self-reported depressed mood and choice stepping reaction time (CSRT) is mediated by psychoactive medication use, physiological performance, and cognitive ability.A total of

  10. Valve cam design using numerical step-by-step method

    OpenAIRE

    Vasilyev, Aleksandr; Bakhracheva, Yuliya; Kabore, Ousman; Zelenskiy, Yuriy

    2014-01-01

    This article studies the numerical step-by-step method of cam profile design. The results of the study are used for designing the internal combustion engine valve gear. This method allows to profile the peak efficiency of cams in view of many restrictions, connected with valve gear serviceability and reliability.

  11. Do restrictive omnibus immigration laws reduce enrollment in public health insurance by Latino citizen children? A comparative interrupted time series study.

    Science.gov (United States)

    Allen, Chenoa D; McNeely, Clea A

    2017-10-01

    In the United States, there is concern that recent state laws restricting undocumented immigrants' rights could threaten access to Medicaid and the Children's Health Insurance Program (CHIP) for citizen children of immigrant parents. Of particular concern are omnibus immigration laws, state laws that include multiple provisions increasing immigration enforcement and restricting rights for undocumented immigrants. These laws could limit Medicaid/CHIP access for citizen children in immigrant families by creating misinformation about their eligibility and fostering fear and mistrust of government among immigrant parents. This study uses nationally-representative data from the National Health Interview Survey (2005-2014; n = 70,187) and comparative interrupted time series methods to assess whether passage of state omnibus immigration laws reduced access to Medicaid/CHIP for US citizen Latino children. We found that law passage did not reduce enrollment for children with noncitizen parents and actually resulted in temporary increases in coverage among Latino children with at least one citizen parent. These findings are surprising in light of prior research. We offer potential explanations for this finding and conclude with a call for future research to be expanded in three ways: 1) examine whether policy effects vary for children of undocumented parents, compared to children whose noncitizen parents are legally present; 2) examine the joint effects of immigration-related policies at different levels, from the city or county to the state to the federal; and 3) draw on the large social movements and political mobilization literature that describes when and how Latinos and immigrants push back against restrictive immigration laws. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Monte Carlo steps per spin vs. time in the master equation II: Glauber kinetics for the infinite-range ising model in a static magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Suhk Kun [Chungbuk National University, Chungbuk (Korea, Republic of)

    2006-01-15

    As an extension of our previous work on the relationship between time in Monte Carlo simulation and time in the continuous master equation in the infinit-range Glauber kinetic Ising model in the absence of any magnetic field, we explored the same model in the presence of a static magnetic field. Monte Carlo steps per spin as time in the MC simulations again turns out to be proportional to time in the master equation for the model in relatively larger static magnetic fields at any temperature. At and near the critical point in a relatively smaller magnetic field, the model exhibits a significant finite-size dependence, and the solution to the Suzuki-Kubo differential equation stemming from the master equation needs to be re-scaled to fit the Monte Carlo steps per spin for the system with different numbers of spins.

  13. Canadian children's and youth's pedometer-determined steps/day, parent-reported TV watching time, and overweight/obesity: The CANPLAY Surveillance Study

    OpenAIRE

    Tudor-Locke, Catrine; Craig, Cora L; Cameron, Christine; Griffiths, Joseph M

    2011-01-01

    Abstract Background This study examines associations between pedometer-determined steps/day and parent-reported child's Body Mass Index (BMI) and time typically spent watching television between school and dinner. Methods Young people (aged 5-19 years) were recruited through their parents by random digit dialling and mailed a data collection package. Information on height and weight and time spent watching television between school and dinner on a typical school day was collected from parents...

  14. Restricted Mobilities

    DEFF Research Database (Denmark)

    Nielsen, Mette; Lassen, Claus

    2012-01-01

    communities and shopping centres through mobility lenses. The article shows how different mobility systems enable and restrict the public access to private-public spaces, and it points out that proprietary communities create an unequal potential for human movement and access in the city. The main argument......Privatisation of public spaces in the contemporary city has increased during the last decades but only few studies have approached this field from a mobility perspective. Therefore the article seeks to rectify this by exploring two Australian examples of private spaces in the city; gated...... and stratification mechanisms. In conclusion the article therefore suggests that future urban research and planning also needs a mobile understanding of spaces in the cities and how different mobility systems play an important role to sustain the exclusiveness that often characterises the private/public spaces...

  15. A novel enterovirus and parechovirus multiplex one-step real-time PCR-validation and clinical experience

    DEFF Research Database (Denmark)

    Nielsen, A. C. Y.; Bottiger, B.; Midgley, S. E.

    2013-01-01

    As the number of new enteroviruses and human parechoviruses seems ever growing, the necessity for updated diagnostics is relevant. We have updated an enterovirus assay and combined it with a previously published assay for human parechovirus resulting in a multiplex one-step RT-PCR assay....... The multiplex assay was validated by analysing the sensitivity and specificity of the assay compared to the respective monoplex assays, and a good concordance was found. Furthermore, the enterovirus assay was able to detect 42 reference strains from all 4 species, and an additional 9 genotypes during panel...... testing and routine usage. During 15 months of routine use, from October 2008 to December 2009, we received and analysed 2187 samples (stool samples, cerebrospinal fluids, blood samples, respiratory samples and autopsy samples) were tested, from 1546 patients and detected enteroviruses and parechoviruses...

  16. STeP: A Tool for the Development of Provably Correct Reactive and Real-Time Systems

    National Research Council Canada - National Science Library

    Manna, Zohar

    1999-01-01

    This research is directed towards the implementation of a comprehensive toolkit for the development and verification of high assurance reactive systems, especially concurrent, real time, and hybrid systems...

  17. A novel enterovirus and parechovirus multiplex one-step real-time PCR-validation and clinical experience.

    Science.gov (United States)

    Nielsen, Alex Christian Yde; Böttiger, Blenda; Midgley, Sofie Elisabeth; Nielsen, Lars Peter

    2013-11-01

    As the number of new enteroviruses and human parechoviruses seems ever growing, the necessity for updated diagnostics is relevant. We have updated an enterovirus assay and combined it with a previously published assay for human parechovirus resulting in a multiplex one-step RT-PCR assay. The multiplex assay was validated by analysing the sensitivity and specificity of the assay compared to the respective monoplex assays, and a good concordance was found. Furthermore, the enterovirus assay was able to detect 42 reference strains from all 4 species, and an additional 9 genotypes during panel testing and routine usage. During 15 months of routine use, from October 2008 to December 2009, we received and analysed 2187 samples (stool samples, cerebrospinal fluids, blood samples, respiratory samples and autopsy samples) were tested, from 1546 patients and detected enteroviruses and parechoviruses in 171 (8%) and 66 (3%) of the samples, respectively. 180 of the positive samples could be genotyped by PCR and sequencing and the most common genotypes found were human parechovirus type 3, echovirus 9, enterovirus 71, Coxsackievirus A16, and echovirus 25. During 2009 in Denmark, both enterovirus and human parechovirus type 3 had a similar seasonal pattern with a peak during the summer and autumn. Human parechovirus type 3 was almost invariably found in children less than 4 months of age. In conclusion, a multiplex assay was developed allowing simultaneous detection of 2 viruses, which can cause similar clinical symptoms. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Effect of different air-drying time on the microleakage of single-step self-etch adhesives

    OpenAIRE

    Moosavi, Horieh; Forghani, Maryam; Managhebi, Esmatsadat

    2013-01-01

    Objectives This study evaluated the effect of three different air-drying times on microleakage of three self-etch adhesive systems. Materials and Methods Class I cavities were prepared for 108 extracted sound human premolars. The teeth were divided into three main groups based on three different adhesives: Opti Bond All in One (OBAO), Clearfil S3 Bond (CSB), Bond Force (BF). Each main group divided into three subgroups regarding the air-drying time: without application of air stream...

  19. Stepwise identification of HLA-A*0201-restricted CD8+ T-cell epitope peptides from herpes simplex virus type 1 genome boosted by a StepRank scheme.

    Science.gov (United States)

    Bi, Jianjun; Song, Rengang; Yang, Huilan; Li, Bingling; Fan, Jianyong; Liu, Zhongrong; Long, Chaoqin

    2011-01-01

    Identification of immunodominant epitopes is the first step in the rational design of peptide vaccines aimed at T-cell immunity. To date, however, it is yet a great challenge for accurately predicting the potent epitope peptides from a pool of large-scale candidates with an efficient manner. In this study, a method that we named StepRank has been developed for the reliable and rapid prediction of binding capabilities/affinities between proteins and genome-wide peptides. In this procedure, instead of single strategy used in most traditional epitope identification algorithms, four steps with different purposes and thus different computational demands are employed in turn to screen the large-scale peptide candidates that are normally generated from, for example, pathogenic genome. The steps 1 and 2 aim at qualitative exclusion of typical nonbinders by using empirical rule and linear statistical approach, while the steps 3 and 4 focus on quantitative examination and prediction of the interaction energy profile and binding affinity of peptide to target protein via quantitative structure-activity relationship (QSAR) and structure-based free energy analysis. We exemplify this method through its application to binding predictions of the peptide segments derived from the 76 known open-reading frames (ORFs) of herpes simplex virus type 1 (HSV-1) genome with or without affinity to human major histocompatibility complex class I (MHC I) molecule HLA-A*0201, and find that the predictive results are well compatible with the classical anchor residue theory and perfectly match for the extended motif pattern of MHC I-binding peptides. The putative epitopes are further confirmed by comparisons with 11 experimentally measured HLA-A*0201-restrcited peptides from the HSV-1 glycoproteins D and K. We expect that this well-designed scheme can be applied in the computational screening of other viral genomes as well.

  20. Time will tell: community acceptability of HIV vaccine research before and after the “Step Study” vaccine discontinuation

    Directory of Open Access Journals (Sweden)

    Paula M Frew

    2010-09-01

    Full Text Available Paula M Frew1,2,3,4, Mark J Mulligan1,2,3, Su-I Hou5, Kayshin Chan3, Carlos del Rio1,2,3,61Department of Medicine, Division of Infectious Diseases, Emory University School of Medicine, Atlanta, Georgia, USA; 2Emory Center for AIDS Research, Atlanta, Georgia, USA; 3The Hope Clinic of the Emory Vaccine Center, Decatur, Georgia, USA; 4Department of Behavioral Sciences and Health Education, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA; 5Department of Health Promotion and Behavior, College of Public Health, University of Georgia, Athens, Georgia, USA; 6Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USAObjective: This study examines whether men-who-have-sex-with-men (MSM and transgender (TG persons’ attitudes, beliefs, and risk perceptions toward human immunodeficiency virus (HIV vaccine research have been altered as a result of the negative findings from a phase 2B HIV vaccine study.Design: We conducted a cross-sectional survey among MSM and TG persons (N = 176 recruited from community settings in Atlanta from 2007 to 2008. The first group was recruited during an active phase 2B HIV vaccine trial in which a candidate vaccine was being evaluated (the “Step Study”, and the second group was recruited after product futility was widely reported in the media.Methods: Descriptive statistics, t tests, and chi-square tests were conducted to ascertain differences between the groups, and ordinal logistic regressions examined the influences of the above-mentioned factors on a critical outcome, future HIV vaccine study participation. The ordinal regression outcomes evaluated the influences on disinclination, neutrality, and inclination to study participation.Results: Behavioral outcomes such as future recruitment, event attendance, study promotion, and community mobilization did not reveal any differences in participants’ intentions between the groups. However, we observed

  1. Dynamical Constants and Time Universals: A First Step toward a Metrical Definition of Ordered and Abnormal Cognition.

    Science.gov (United States)

    Elliott, Mark A; du Bois, Naomi

    2017-01-01

    From the point of view of the cognitive dynamicist the organization of brain circuitry into assemblies defined by their synchrony at particular (and precise) oscillation frequencies is important for the correct correlation of all independent cortical responses to the different aspects of a given complex thought or object. From the point of view of anyone operating complex mechanical systems, i.e., those comprising independent components that are required to interact precisely in time, it follows that the precise timing of such a system is essential - not only essential but measurable, and scalable. It must also be reliable over observations to bring about consistent behavior, whatever that behavior is. The catastrophic consequence of an absence of such precision, for instance that required to govern the interference engine in many automobiles, is indicative of how important timing is for the function of dynamical systems at all levels of operation. The dynamics and temporal considerations combined indicate that it is necessary to consider the operating characteristic of any dynamical, cognitive brain system in terms, superficially at least, of oscillation frequencies. These may, themselves, be forensic of an underlying time-related taxonomy. Currently there are only two sets of relevant and necessarily systematic observations in this field: one of these reports the precise dynamical structure of the perceptual systems engaged in dynamical binding across form and time; the second, derived both empirically from perceptual performance data, as well as obtained from theoretical models, demonstrates a timing taxonomy related to a fundamental operator referred to as the time quantum. In this contribution both sets of theory and observations are reviewed and compared for their predictive consistency. Conclusions about direct comparability are discussed for both theories of cognitive dynamics and time quantum models. Finally, a brief review of some experimental data

  2. Bonding and Bridging Social Capital in Step- and First-Time Families and the Issue of Family Boundaries

    Directory of Open Access Journals (Sweden)

    Gaëlle Aeby

    2014-06-01

    Full Text Available Divorce and remarriage usually imply a redefinition of family boundaries, with consequences for the production and availability of social capital. This research shows that bonding and bridging social capitals are differentially made available by families. It first hypothesizes that bridging social capital is more likely to be developed in stepfamilies, and bonding social capital in first-time families. Second, the boundaries of family configurations are expected to vary within stepfamilies and within first-time families creating a diversity of family configurations within both structures. Third, in both cases, social capital is expected to depend on the ways in which their family boundaries are set up by individuals by including or excluding ex-partners, new partner's children, siblings, and other family ties. The study is based on a sample of 300 female respondents who have at least one child of their own between 5 and 13 years, 150 from a stepfamily structure and 150 from a first-time family structure. Social capital is empirically operationalized as perceived emotional support in family networks. The results show that individuals in first-time families more often develop bonding social capital and individuals in stepfamilies bridging social capital. In both cases, however, individuals in family configurations based on close blood and conjugal ties more frequently develop bonding social capital, whereas individuals in family configurations based on in-law, stepfamily or friendship ties are more likely to develop bridging social capital.

  3. Standardization of a two-step real-time polymerase chain reaction based method for species-specific detection of medically important Aspergillus species.

    Science.gov (United States)

    Das, P; Pandey, P; Harishankar, A; Chandy, M; Bhattacharya, S; Chakrabarti, A

    2017-01-01

    Standardization of Aspergillus polymerase chain reaction (PCR) poses two technical challenges (a) standardization of DNA extraction, (b) optimization of PCR against various medically important Aspergillus species. Many cases of aspergillosis go undiagnosed because of relative insensitivity of conventional diagnostic methods such as microscopy, culture or antigen detection. The present study is an attempt to standardize real-time PCR assay for rapid sensitive and specific detection of Aspergillus DNA in EDTA whole blood. Three nucleic acid extraction protocols were compared and a two-step real-time PCR assay was developed and validated following the recommendations of the European Aspergillus PCR Initiative in our setup. In the first PCR step (pan-Aspergillus PCR), the target was 28S rDNA gene, whereas in the second step, species specific PCR the targets were beta-tubulin (for Aspergillus fumigatus, Aspergillus flavus, Aspergillus terreus), gene and calmodulin gene (for Aspergillus niger). Species specific identification of four medically important Aspergillus species, namely, A. fumigatus, A. flavus, A. niger and A. terreus were achieved by this PCR. Specificity of the PCR was tested against 34 different DNA source including bacteria, virus, yeast, other Aspergillus sp., other fungal species and for human DNA and had no false-positive reactions. The analytical sensitivity of the PCR was found to be 102 CFU/ml. The present protocol of two-step real-time PCR assays for genus- and species-specific identification for commonly isolated species in whole blood for diagnosis of invasive Aspergillus infections offers a rapid, sensitive and specific assay option and requires clinical validation at multiple centers.

  4. Microsoft Office professional 2010 step by step

    CERN Document Server

    Cox, Joyce; Frye, Curtis

    2011-01-01

    Teach yourself exactly what you need to know about using Office Professional 2010-one step at a time! With STEP BY STEP, you build and practice new skills hands-on, at your own pace. Covering Microsoft Word, PowerPoint, Outlook, Excel, Access, Publisher, and OneNote, this book will help you learn the core features and capabilities needed to: Create attractive documents, publications, and spreadsheetsManage your e-mail, calendar, meetings, and communicationsPut your business data to workDevelop and deliver great presentationsOrganize your ideas and notes in one placeConnect, share, and accom

  5. Sleep restriction therapy for insomnia is associated with reduced objective total sleep time, increased daytime somnolence, and objectively impaired vigilance: implications for the clinical management of insomnia disorder.

    Science.gov (United States)

    Kyle, Simon D; Miller, Christopher B; Rogers, Zoe; Siriwardena, A Niroshan; Macmahon, Kenneth M; Espie, Colin A

    2014-02-01

    To investigate whether sleep restriction therapy (SRT) is associated with reduced objective total sleep time (TST), increased daytime somnolence, and impaired vigilance. Within-subject, noncontrolled treatment investigation. Sleep research laboratory. Sixteen patients [10 female, mean age = 47.1 (10.8) y] with well-defined psychophysiological insomnia (PI), reporting TST ≤ 6 h. Patients were treated with single-component SRT over a 4-w protocol, sleeping in the laboratory for 2 nights prior to treatment initiation and for 3 nights (SRT night 1, 8, 22) during the acute interventional phase. The psychomotor vigilance task (PVT) was completed at seven defined time points [day 0 (baseline), day 1,7,8,21,22 (acute treatment) and day 84 (3 mo)]. The Epworth Sleepiness Scale (ESS) was completed at baseline, w 1-4, and 3 mo. Subjective sleep outcomes and global insomnia severity significantly improved before and after SRT. There was, however, a robust decrease in PSG-defined TST during acute implementation of SRT, by an average of 91 min on night 1, 78 min on night 8, and 69 min on night 22, relative to baseline (P insomnia.

  6. Gas flushing through hyper-acidic crater lakes: the next steps within a reframed monitoring time window

    Science.gov (United States)

    Rouwet, Dmitri

    2016-04-01

    Tracking variations in the chemical composition, water temperature and pH of brines from peak-activity crater lakes is the most obvious way to forecast phreatic activity. Volcano monitoring intrinsically implies a time window of observation that should be synchronised with the kinetics of magmatic processes, such as degassing and magma intrusion. To decipher "how much time ago" a variation in degassing regime actually occurred before eventually being detected in a crater lake is key, and depends on the lake water residence time. The above reasoning assumes that gas is preserved as anions in the lake water (SO4, Cl, F anions), in other words, that scrubbing of acid gases is complete and irreversible. Less is true. Recent work has confirmed, by direct MultiGas measurement from evaporative plumes, that even the strongest acid in liquid medium (i.e. SO2) degasses from hyper-acidic crater lakes. The less strong acid HCl has long been recognised as being more volatile than hydrophyle in extremely acidic solutions (pH near 0), through a long-term steady increase in SO4/Cl ratios in the vigorously evaporating crater lake of Poás volcano. We now know that acidic gases flush through hyper-acidic crater lake brines, but we don't know to which extend (completely or partially?), and with which speed. The chemical composition hence only reflects a transient phase of the gas flushing through the lake. In terms of volcanic surveillance this brings the advantage that the monitoring time window is definitely shorter than defined by the water chemistry, but yet, we do not know how much shorter. Empirical experiments by Capaccioni et al. (in press) have tried to tackle this kinetic problem for HCl degassing from a "lab-lake" on the short-term (2 days). With this state of the art in mind, two new monitoring strategies can be proposed to seek for precursory signals of phreatic eruptions from crater lakes: (1) Tracking variations in gas compositions, fluxes and ratios between species in

  7. Two-step Laser Time-of-Flight Mass Spectrometry to Elucidate Organic Diversity in Planetary Surface Materials.

    Science.gov (United States)

    Getty, Stephanie A.; Brinckerhoff, William B.; Cornish, Timothy; Li, Xiang; Floyd, Melissa; Arevalo, Ricardo Jr.; Cook, Jamie Elsila; Callahan, Michael P.

    2013-01-01

    Laser desorption/ionization time-of-flight mass spectrometry (LD-TOF-MS) holds promise to be a low-mass, compact in situ analytical capability for future landed missions to planetary surfaces. The ability to analyze a solid sample for both mineralogical and preserved organic content with laser ionization could be compelling as part of a scientific mission pay-load that must be prepared for unanticipated discoveries. Targeted missions for this instrument capability include Mars, Europa, Enceladus, and small icy bodies, such as asteroids and comets.

  8. Nucleoside uptake in macrophages from various murine strains: a short-time and a two-step stimulation model

    International Nuclear Information System (INIS)

    Busolo, F.; Conventi, L.; Grigolon, M.; Palu, G.

    1991-01-01

    Kinetics of [3H]-uridine uptake by murine peritoneal macrophages (pM phi) is early altered after exposure to a variety of stimuli. Alterations caused by Candida albicans, lipopolysaccharide (LPS) and recombinant interferon-gamma (rIFN-gamma) were similar in SAVO, C57BL/6, C3H/HeN and C3H/HeJ mice, and were not correlated with an activation process as shown by the amount of tumor necrosis factor-alpha (TNF-alpha) being released. Short-time exposure to all stimuli resulted in an increased nucleoside uptake by SAVO pM phi, suggesting that the tumoricidal function of this cell either depends from the type of stimulus or the time when the specific interaction with the cell receptor is taking place. Experiments with priming and triggering signals confirmed the above findings, indicating that the increase or the decrease of nucleoside uptake into the cell depends essentially on the chemical nature of the priming stimulus. The triggering stimulus, on the other hand, is only able to amplify the primary response

  9. The Influences of Time and Velocity of Inert Gas on the Quality of theProcessing Product of Graphite Matrix on the Baking Step

    International Nuclear Information System (INIS)

    Imam-Dahroni; Dwi-Herwidhi; NS, Kasilani

    2000-01-01

    The research of the synthesis of matrix graphite on the step of bakingprocess was conducted, by focusing on the influence of time and velocityvariables of the inert gas. The investigation on baking times ranging from 5minutes to 55 minutes and by varying the velocity of inert gas from 0.30l/minute to 3.60 l/minute, resulted the product of different matrix.Optimizing at the time of operation and the flow rate of argon gas indicatedthat the baking time for 30 minutes and by the flow rate of argon gas of 2.60l/minute resulted best matrix graphite that has a hardness value of 11kg/mm 2 of hardness and the ductility of 1800 Newton. (author)

  10. Time-varying impedance of the human ankle in the sagittal and frontal planes during straight walk and turning steps.

    Science.gov (United States)

    Ficanha, Evandro M; Ribeiro, Guilherme A; Knop, Lauren; Rastgaar, Mo

    2017-07-01

    This paper describes the methods and experiment protocols for estimation of the human ankle impedance during turning and straight line walking. The ankle impedance of two human subjects during the stance phase of walking in both dorsiflexion plantarflexion (DP) and inversion eversion (IE) were estimated. The impedance was estimated about 8 axes of rotations of the human ankle combining different amounts of DP and IE rotations, and differentiating among positive and negative rotations at 5 instants of the stance length (SL). Specifically, the impedance was estimated at 10%, 30%, 50%, 70% and 90% of the SL. The ankle impedance showed great variability across time, and across the axes of rotation, with consistent larger stiffness and damping in DP than IE. When comparing straight walking and turning, the main differences were in damping at 50%, 70%, and 90% of the SL with an increase in damping at all axes of rotation during turning.

  11. Molecular motion in restricted geometries

    Indian Academy of Sciences (India)

    Molecular dynamics in restricted geometries is known to exhibit anomalous behaviour. Diffusion, translational or rotational, of molecules is altered significantly on confinement in restricted geometries. Quasielastic neutron scattering (QENS) offers a unique possibility of studying molecular motion in such systems. Both time ...

  12. The design of a real-time formative evaluation of the implementation process of lifestyle interventions at two worksites using a 7-step strategy (BRAVO@Work).

    Science.gov (United States)

    Wierenga, Debbie; Engbers, Luuk H; van Empelen, Pepijn; Hildebrandt, Vincent H; van Mechelen, Willem

    2012-08-07

    Worksite health promotion programs (WHPPs) offer an attractive opportunity to improve the lifestyle of employees. Nevertheless, broad scale and successful implementation of WHPPs in daily practice often fails. In the present study, called BRAVO@Work, a 7-step implementation strategy was used to develop, implement and embed a WHPP in two different worksites with a focus on multiple lifestyle interventions.This article describes the design and framework for the formative evaluation of this 7-step strategy under real-time conditions by an embedded scientist with the purpose to gain insight into whether this this 7-step strategy is a useful and effective implementation strategy. Furthermore, we aim to gain insight into factors that either facilitate or hamper the implementation process, the quality of the implemented lifestyle interventions and the degree of adoption, implementation and continuation of these interventions. This study is a formative evaluation within two different worksites with an embedded scientist on site to continuously monitor the implementation process. Each worksite (i.e. a University of Applied Sciences and an Academic Hospital) will assign a participating faculty or a department, to implement a WHPP focusing on lifestyle interventions using the 7-step strategy. The primary focus will be to describe the natural course of development, implementation and maintenance of a WHPP by studying [a] the use and adherence to the 7-step strategy, [b] barriers and facilitators that influence the natural course of adoption, implementation and maintenance, and [c] the implementation process of the lifestyle interventions. All data will be collected using qualitative (i.e. real-time monitoring and semi-structured interviews) and quantitative methods (i.e. process evaluation questionnaires) applying data triangulation. Except for the real-time monitoring, the data collection will take place at baseline and after 6, 12 and 18 months. This is one of the few

  13. The design of a real-time formative evaluation of the implementation process of lifestyle interventions at two worksites using a 7-step strategy (BRAVO@Work

    Directory of Open Access Journals (Sweden)

    Wierenga Debbie

    2012-08-01

    Full Text Available Abstract Background Worksite health promotion programs (WHPPs offer an attractive opportunity to improve the lifestyle of employees. Nevertheless, broad scale and successful implementation of WHPPs in daily practice often fails. In the present study, called BRAVO@Work, a 7-step implementation strategy was used to develop, implement and embed a WHPP in two different worksites with a focus on multiple lifestyle interventions. This article describes the design and framework for the formative evaluation of this 7-step strategy under real-time conditions by an embedded scientist with the purpose to gain insight into whether this this 7-step strategy is a useful and effective implementation strategy. Furthermore, we aim to gain insight into factors that either facilitate or hamper the implementation process, the quality of the implemented lifestyle interventions and the degree of adoption, implementation and continuation of these interventions. Methods and design This study is a formative evaluation within two different worksites with an embedded scientist on site to continuously monitor the implementation process. Each worksite (i.e. a University of Applied Sciences and an Academic Hospital will assign a participating faculty or a department, to implement a WHPP focusing on lifestyle interventions using the 7-step strategy. The primary focus will be to describe the natural course of development, implementation and maintenance of a WHPP by studying [a] the use and adherence to the 7-step strategy, [b] barriers and facilitators that influence the natural course of adoption, implementation and maintenance, and [c] the implementation process of the lifestyle interventions. All data will be collected using qualitative (i.e. real-time monitoring and semi-structured interviews and quantitative methods (i.e. process evaluation questionnaires applying data triangulation. Except for the real-time monitoring, the data collection will take place at baseline and

  14. Assessment of time-dependent density functional theory with the restricted excitation space approximation for excited state calculations of large systems

    Science.gov (United States)

    Hanson-Heine, Magnus W. D.; George, Michael W.; Besley, Nicholas A.

    2018-06-01

    The restricted excitation subspace approximation is explored as a basis to reduce the memory storage required in linear response time-dependent density functional theory (TDDFT) calculations within the Tamm-Dancoff approximation. It is shown that excluding the core orbitals and up to 70% of the virtual orbitals in the construction of the excitation subspace does not result in significant changes in computed UV/vis spectra for large molecules. The reduced size of the excitation subspace greatly reduces the size of the subspace vectors that need to be stored when using the Davidson procedure to determine the eigenvalues of the TDDFT equations. Furthermore, additional screening of the two-electron integrals in combination with a reduction in the size of the numerical integration grid used in the TDDFT calculation leads to significant computational savings. The use of these approximations represents a simple approach to extend TDDFT to the study of large systems and make the calculations increasingly tractable using modest computing resources.

  15. Bias and precision of methods for estimating the difference in restricted mean survival time from an individual patient data meta-analysis

    Directory of Open Access Journals (Sweden)

    Béranger Lueza

    2016-03-01

    Full Text Available Abstract Background The difference in restricted mean survival time ( rmstD t ∗ $$ rmstD\\left({t}^{\\ast}\\right $$ , the area between two survival curves up to time horizon t ∗ $$ {t}^{\\ast } $$ , is often used in cost-effectiveness analyses to estimate the treatment effect in randomized controlled trials. A challenge in individual patient data (IPD meta-analyses is to account for the trial effect. We aimed at comparing different methods to estimate the rmstD t ∗ $$ rmstD\\left({t}^{\\ast}\\right $$ from an IPD meta-analysis. Methods We compared four methods: the area between Kaplan-Meier curves (experimental vs. control arm ignoring the trial effect (Naïve Kaplan-Meier; the area between Peto curves computed at quintiles of event times (Peto-quintile; the weighted average of the areas between either trial-specific Kaplan-Meier curves (Pooled Kaplan-Meier or trial-specific exponential curves (Pooled Exponential. In a simulation study, we varied the between-trial heterogeneity for the baseline hazard and for the treatment effect (possibly correlated, the overall treatment effect, the time horizon t ∗ $$ {t}^{\\ast } $$ , the number of trials and of patients, the use of fixed or DerSimonian-Laird random effects model, and the proportionality of hazards. We compared the methods in terms of bias, empirical and average standard errors. We used IPD from the Meta-Analysis of Chemotherapy in Nasopharynx Carcinoma (MAC-NPC and its updated version MAC-NPC2 for illustration that included respectively 1,975 and 5,028 patients in 11 and 23 comparisons. Results The Naïve Kaplan-Meier method was unbiased, whereas the Pooled Exponential and, to a much lesser extent, the Pooled Kaplan-Meier methods showed a bias with non-proportional hazards. The Peto-quintile method underestimated the rmstD t ∗ $$ rmstD\\left({t}^{\\ast}\\right $$ , except with non-proportional hazards at t ∗ $$ {t}^{\\ast } $$ = 5 years. In the presence of treatment effect

  16. A Two-Step Lyssavirus Real-Time Polymerase Chain Reaction Using Degenerate Primers with Superior Sensitivity to the Fluorescent Antigen Test

    Directory of Open Access Journals (Sweden)

    Vanessa Suin

    2014-01-01

    Full Text Available A generic two-step lyssavirus real-time reverse transcriptase polymerase chain reaction (qRT-PCR, based on a nested PCR strategy, was validated for the detection of different lyssavirus species. Primers with 17 to 30% of degenerate bases were used in both consecutive steps. The assay could accurately detect RABV, LBV, MOKV, DUVV, EBLV-1, EBLV-2, and ABLV. In silico sequence alignment showed a functional match with the remaining lyssavirus species. The diagnostic specificity was 100% and the sensitivity proved to be superior to that of the fluorescent antigen test. The limit of detection was ≤1 50% tissue culture infectious dose. The related vesicular stomatitis virus was not recognized, confirming the selectivity for lyssaviruses. The assay was applied to follow the evolution of rabies virus infection in the brain of mice from 0 to 10 days after intranasal inoculation. The obtained RNA curve corresponded well with the curves obtained by a one-step monospecific RABV-qRT-PCR, the fluorescent antigen test, and virus titration. Despite the presence of degenerate bases, the assay proved to be highly sensitive, specific, and reproducible.

  17. A two-step lyssavirus real-time polymerase chain reaction using degenerate primers with superior sensitivity to the fluorescent antigen test.

    Science.gov (United States)

    Suin, Vanessa; Nazé, Florence; Francart, Aurélie; Lamoral, Sophie; De Craeye, Stéphane; Kalai, Michael; Van Gucht, Steven

    2014-01-01

    A generic two-step lyssavirus real-time reverse transcriptase polymerase chain reaction (qRT-PCR), based on a nested PCR strategy, was validated for the detection of different lyssavirus species. Primers with 17 to 30% of degenerate bases were used in both consecutive steps. The assay could accurately detect RABV, LBV, MOKV, DUVV, EBLV-1, EBLV-2, and ABLV. In silico sequence alignment showed a functional match with the remaining lyssavirus species. The diagnostic specificity was 100% and the sensitivity proved to be superior to that of the fluorescent antigen test. The limit of detection was ≤ 1 50% tissue culture infectious dose. The related vesicular stomatitis virus was not recognized, confirming the selectivity for lyssaviruses. The assay was applied to follow the evolution of rabies virus infection in the brain of mice from 0 to 10 days after intranasal inoculation. The obtained RNA curve corresponded well with the curves obtained by a one-step monospecific RABV-qRT-PCR, the fluorescent antigen test, and virus titration. Despite the presence of degenerate bases, the assay proved to be highly sensitive, specific, and reproducible.

  18. Effects of over-the-counter sales restriction of antibiotics on substitution with medicines for symptoms relief of cold in Mexico and Brazil: time series analysis.

    Science.gov (United States)

    Santa-Ana-Tellez, Yared; Mantel-Teeuwisse, Aukje K; Leufkens, Hubert G M; Wirtz, Veronika J

    2016-11-01

    We evaluated changes in the use of non-steroidal anti-inflammatory drugs (NSAIDs), non-opioid analgesics and cough and cold medicines and its relation with the use of antibiotics after the over-the-counter (OTC) antibiotic sales restrictions in Mexico and Brazil. IMS Health provided retail quarterly data from the private sectors in Mexico and Brazil from the first quarter of 2007 to the first quarter of 2013. Data of each active substance of antibiotics, easily accessible medicines perceived as antibiotics substitutes (cough and cold medicines, analgesics and NSAIDs-the latter two being combined in the analyses), and medicines to control for external factors that can affect the medicines usage trend (antihypertensives) were converted from kilograms to defined daily doses per 1000 inhabitants days (DDD/TID). Interrupted time series were used to estimate changes in level of medicines use at the intervention point and slope after the regulation. The Gregory-Hansen cointegration test was used to explore the relation between the use of antibiotics and perceived substitutes. After the regulation in Mexico NSAIDs-analgesics usage level increased by 1.1 DDD/TID with a slope increase of 0.2 DDD/TID per quarter and the cough and cold medicines usage level increased by 0.4 DDD/TID. In Brazil NSAIDs-analgesics usage level increased by 1.9 DDD/TID, and cough and cold medicines did not change. In the two countries, NSAIDs-analgesics usage changes were related with antibiotic usage changes; in Mexico cough and cold medicines usage changes had a relation with the antibiotics usage changes. These results showed a substitution effect on the use of other medicines, especially NSAIDs and analgesics, after reinforcement of OTC antibiotics sales restrictions. These regulations aimed to improve the antibiotics use and as a consequence reduce antimicrobial resistance; however, this type of policies should be comprehensive and take into account the potential substitution effects on the use

  19. Detection of SYT-SSX mutant transcripts in formalin-fixed paraffin-embedded sarcoma tissues using one-step reverse transcriptase real-time PCR.

    Science.gov (United States)

    Norlelawati, A T; Mohd Danial, G; Nora, H; Nadia, O; Zatur Rawihah, K; Nor Zamzila, A; Naznin, M

    2016-04-01

    Synovial sarcoma (SS) is a rare cancer and accounts for 5-10% of adult soft tissue sarcomas. Making an accurate diagnosis is difficult due to the overlapping histological features of SS with other types of sarcomas and the non-specific immunohistochemistry profile findings. Molecular testing is thus considered necessary to confirm the diagnosis since more than 90% of SS cases carry the transcript of t(X;18)(p11.2;q11.2). The purpose of this study is to diagnose SS at molecular level by testing for t(X;18) fusion-transcript expression through One-step reverse transcriptase real-time Polymerase Chain Reaction (PCR). Formalin-fixed paraffin-embedded tissue blocks of 23 cases of soft tissue sarcomas, which included 5 and 8 cases reported as SS as the primary diagnosis and differential diagnosis respectively, were retrieved from the Department of Pathology, Tengku Ampuan Afzan Hospital, Kuantan, Pahang. RNA was purified from the tissue block sections and then subjected to One-step reverse transcriptase real-time PCR using sequence specific hydrolysis probes for simultaneous detection of either SYT-SSX1 or SYT-SSX2 fusion transcript. Of the 23 cases, 4 cases were found to be positive for SYT-SSX fusion transcript in which 2 were diagnosed as SS whereas in the 2 other cases, SS was the differential diagnosis. Three cases were excluded due to failure of both amplification assays SYT-SSX and control β-2-microglobulin. The remaining 16 cases were negative for the fusion transcript. This study has shown that the application of One-Step reverse transcriptase real time PCR for the detection SYT-SSX transcript is feasible as an aid in confirming the diagnosis of synovial sarcoma.

  20. The Effect of Phosphoric Acid Pre-etching Times on Bonding Performance and Surface Free Energy with Single-step Self-etch Adhesives.

    Science.gov (United States)

    Tsujimoto, A; Barkmeier, W W; Takamizawa, T; Latta, M A; Miyazaki, M

    2016-01-01

    The purpose of this study was to evaluate the effect of phosphoric acid pre-etching times on shear bond strength (SBS) and surface free energy (SFE) with single-step self-etch adhesives. The three single-step self-etch adhesives used were: 1) Scotchbond Universal Adhesive (3M ESPE), 2) Clearfil tri-S Bond (Kuraray Noritake Dental), and 3) G-Bond Plus (GC). Two no pre-etching groups, 1) untreated enamel and 2) enamel surfaces after ultrasonic cleaning with distilled water for 30 seconds to remove the smear layer, were prepared. There were four pre-etching groups: 1) enamel surfaces were pre-etched with phosphoric acid (Etchant, 3M ESPE) for 3 seconds, 2) enamel surfaces were pre-etched for 5 seconds, 3) enamel surfaces were pre-etched for 10 seconds, and 4) enamel surfaces were pre-etched for 15 seconds. Resin composite was bonded to the treated enamel surface to determine SBS. The SFEs of treated enamel surfaces were determined by measuring the contact angles of three test liquids. Scanning electron microscopy was used to examine the enamel surfaces and enamel-adhesive interface. The specimens with phosphoric acid pre-etching showed significantly higher SBS and SFEs than the specimens without phosphoric acid pre-etching regardless of the adhesive system used. SBS and SFEs did not increase for phosphoric acid pre-etching times over 3 seconds. There were no significant differences in SBS and SFEs between the specimens with and without a smear layer. The data suggest that phosphoric acid pre-etching of ground enamel improves the bonding performance of single-step self-etch adhesives, but these bonding properties do not increase for phosphoric acid pre-etching times over 3 seconds.

  1. Multi-time-step ahead daily and hourly intermittent reservoir inflow prediction by artificial intelligent techniques using lumped and distributed data

    Science.gov (United States)

    Jothiprakash, V.; Magar, R. B.

    2012-07-01

    SummaryIn this study, artificial intelligent (AI) techniques such as artificial neural network (ANN), Adaptive neuro-fuzzy inference system (ANFIS) and Linear genetic programming (LGP) are used to predict daily and hourly multi-time-step ahead intermittent reservoir inflow. To illustrate the applicability of AI techniques, intermittent Koyna river watershed in Maharashtra, India is chosen as a case study. Based on the observed daily and hourly rainfall and reservoir inflow various types of time-series, cause-effect and combined models are developed with lumped and distributed input data. Further, the model performance was evaluated using various performance criteria. From the results, it is found that the performances of LGP models are found to be superior to ANN and ANFIS models especially in predicting the peak inflows for both daily and hourly time-step. A detailed comparison of the overall performance indicated that the combined input model (combination of rainfall and inflow) performed better in both lumped and distributed input data modelling. It was observed that the lumped input data models performed slightly better because; apart from reducing the noise in the data, the better techniques and their training approach, appropriate selection of network architecture, required inputs, and also training-testing ratios of the data set. The slight poor performance of distributed data is due to large variations and lesser number of observed values.

  2. Rapid detection of Enterovirus and Coxsackievirus A10 by a TaqMan based duplex one-step real time RT-PCR assay.

    Science.gov (United States)

    Chen, Jingfang; Zhang, Rusheng; Ou, Xinhua; Yao, Dong; Huang, Zheng; Li, Linzhi; Sun, Biancheng

    2017-06-01

    A TaqMan based duplex one-step real time RT-PCR (rRT-PCR) assay was developed for the rapid detection of Coxsackievirus A10 (CV-A10) and other enterovirus (EVs) in clinical samples. The assay was fully evaluated and found to be specific and sensitive. When applied in 115 clinical samples, a 100% diagnostic sensitivity in CV-A10 detection and 97.4% diagnostic sensitivity in other EVs were found. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Moment analysis of the time-dependent transmission of a step-function input of a radioactive gas through an adsorber bed

    International Nuclear Information System (INIS)

    Lee, T.V.; Rothstein, D.; Madey, R.

    1986-01-01

    The time-dependent concentration of a radioactive gas at the outlet of an adsorber bed for a step change in the input concentration is analyzed by the method of moments. This moment analysis yields analytical expressions for calculating the kinetic parameters of a gas adsorbed on a porous solid in terms of observables from a time-dependent transmission curve. Transmission is the ratio of the adsorbate outlet concentration to that at the inlet. The three nonequilibrium parameters are the longitudinal diffusion coefficient, the solid-phase diffusion coefficient, and the interfacial mass-transfer coefficient. Three quantities that can be extracted in principle from an experimental transmission curve are the equilibrium transmission, the average residence (or propagation) time, and the first-moment relative to the propagation time. The propagation time for a radioactive gas is given by the time integral of one minus the transmission (expressed as a fraction of the steady-state transmission). The steady-state transmission, the propagation time, and the first-order moment are functions of the three kinetic parameters and the equilibrium adsorption capacity. The equilibrium adsorption capacity is extracted from an experimental transmission curve for a stable gaseous isotope. The three kinetic parameters can be obtained by solving the three analytical expressions simultaneously. No empirical correlations are required

  4. Compact Two-step Laser Time-of-Flight Mass Spectrometer for in Situ Analyses of Aromatic Organics on Planetary Missions

    Science.gov (United States)

    Getty, Stephanie; Brickerhoff, William; Cornish, Timothy; Ecelberger, Scott; Floyd, Melissa

    2012-01-01

    RATIONALE A miniature time-of-flight mass spectrometer has been adapted to demonstrate two-step laser desorption-ionization (LOI) in a compact instrument package for enhanced organics detection. Two-step LDI decouples the desorption and ionization processes, relative to traditional laser ionization-desorption, in order to produce low-fragmentation conditions for complex organic analytes. Tuning UV ionization laser energy allowed control ofthe degree of fragmentation, which may enable better identification of constituent species. METHODS A reflectron time-of-flight mass spectrometer prototype measuring 20 cm in length was adapted to a two-laser configuration, with IR (1064 nm) desorption followed by UV (266 nm) postionization. A relatively low ion extraction voltage of 5 kV was applied at the sample inlet. Instrument capabilities and performance were demonstrated with analysis of a model polycyclic aromatic hydrocarbon, representing a class of compounds important to the fields of Earth and planetary science. RESULTS L2MS analysis of a model PAH standard, pyrene, has been demonstrated, including parent mass identification and the onset o(tunable fragmentation as a function of ionizing laser energy. Mass resolution m/llm = 380 at full width at half-maximum was achieved which is notable for gas-phase ionization of desorbed neutrals in a highly-compact mass analyzer. CONCLUSIONS Achieving two-step laser mass spectrometry (L2MS) in a highly-miniature instrument enables a powerful approach to the detection and characterization of aromatic organics in remote terrestrial and planetary applications. Tunable detection of parent and fragment ions with high mass resolution, diagnostic of molecular structure, is possible on such a compact L2MS instrument. Selectivity of L2MS against low-mass inorganic salt interferences is a key advantage when working with unprocessed, natural samples, and a mechanism for the observed selectivity is presented.

  5. A new and inexpensive non-bit-for-bit solution reproducibility test based on time step convergence (TSC1.0)

    Science.gov (United States)

    Wan, Hui; Zhang, Kai; Rasch, Philip J.; Singh, Balwinder; Chen, Xingyuan; Edwards, Jim

    2017-02-01

    A test procedure is proposed for identifying numerically significant solution changes in evolution equations used in atmospheric models. The test issues a fail signal when any code modifications or computing environment changes lead to solution differences that exceed the known time step sensitivity of the reference model. Initial evidence is provided using the Community Atmosphere Model (CAM) version 5.3 that the proposed procedure can be used to distinguish rounding-level solution changes from impacts of compiler optimization or parameter perturbation, which are known to cause substantial differences in the simulated climate. The test is not exhaustive since it does not detect issues associated with diagnostic calculations that do not feedback to the model state variables. Nevertheless, it provides a practical and objective way to assess the significance of solution changes. The short simulation length implies low computational cost. The independence between ensemble members allows for parallel execution of all simulations, thus facilitating fast turnaround. The new method is simple to implement since it does not require any code modifications. We expect that the same methodology can be used for any geophysical model to which the concept of time step convergence is applicable.

  6. Long-term prediction of chaotic time series with multi-step prediction horizons by a neural network with Levenberg-Marquardt learning algorithm

    International Nuclear Information System (INIS)

    Mirzaee, Hossein

    2009-01-01

    The Levenberg-Marquardt learning algorithm is applied for training a multilayer perception with three hidden layer each with ten neurons in order to carefully map the structure of chaotic time series such as Mackey-Glass time series. First the MLP network is trained with 1000 data, and then it is tested with next 500 data. After that the trained and tested network is applied for long-term prediction of next 120 data which come after test data. The prediction is such a way that, the first inputs to network for prediction are the four last data of test data, then the predicted value is shifted to the regression vector which is the input to the network, then after first four-step of prediction, the input regression vector to network is fully predicted values and in continue, each predicted data is shifted to input vector for subsequent prediction.

  7. A Straightforward Convergence Method for ICCG Simulation of Multiloop and Time-Stepping FE Model of Synchronous Generators with Simultaneous AC and Rectified DC Connections

    Directory of Open Access Journals (Sweden)

    Shanming Wang

    2015-01-01

    Full Text Available Now electric machines integrate with power electronics to form inseparable systems in lots of applications for high performance. For such systems, two kinds of nonlinearities, the magnetic nonlinearity of iron core and the circuit nonlinearity caused by power electronics devices, coexist at the same time, which makes simulation time-consuming. In this paper, the multiloop model combined with FE model of AC-DC synchronous generators, as one example of electric machine with power electronics system, is set up. FE method is applied for magnetic nonlinearity and variable-step variable-topology simulation method is applied for circuit nonlinearity. In order to improve the simulation speed, the incomplete Cholesky conjugate gradient (ICCG method is used to solve the state equation. However, when power electronics device switches off, the convergence difficulty occurs. So a straightforward approach to achieve convergence of simulation is proposed. At last, the simulation results are compared with the experiments.

  8. A New Quaternion-Based Kalman Filter for Real-Time Attitude Estimation Using the Two-Step Geometrically-Intuitive Correction Algorithm.

    Science.gov (United States)

    Feng, Kaiqiang; Li, Jie; Zhang, Xiaoming; Shen, Chong; Bi, Yu; Zheng, Tao; Liu, Jun

    2017-09-19

    In order to reduce the computational complexity, and improve the pitch/roll estimation accuracy of the low-cost attitude heading reference system (AHRS) under conditions of magnetic-distortion, a novel linear Kalman filter, suitable for nonlinear attitude estimation, is proposed in this paper. The new algorithm is the combination of two-step geometrically-intuitive correction (TGIC) and the Kalman filter. In the proposed algorithm, the sequential two-step geometrically-intuitive correction scheme is used to make the current estimation of pitch/roll immune to magnetic distortion. Meanwhile, the TGIC produces a computed quaternion input for the Kalman filter, which avoids the linearization error of measurement equations and reduces the computational complexity. Several experiments have been carried out to validate the performance of the filter design. The results demonstrate that the mean time consumption and the root mean square error (RMSE) of pitch/roll estimation under magnetic disturbances are reduced by 45.9% and 33.8%, respectively, when compared with a standard filter. In addition, the proposed filter is applicable for attitude estimation under various dynamic conditions.

  9. Coronary computed tomography angiography using prospective electrocardiography-gated axial scans with 64-detector computed tomography. Evaluation of stair-step artifacts and padding time

    International Nuclear Information System (INIS)

    Kimura, Fumiko; Umezawa, Tatsuo; Asano, Tomonari; Chihara, Ruri; Nishi, Naoko; Nishimura, Shigeyoshi; Sakai, Fumikazu

    2010-01-01

    We compared stair-step artifacts and radiation dose between prospective electrocardiography (ECG)-gated coronary computed tomography angiography (prospective CCTA) and retrospective CCTA using 64-detector CT and determined the optimal padding time (PT) for prospective CCTA. We retrospectively evaluated 183 patients [mean heart rate (HR) <65 beats/min, maximum HR instability <5 beats/min] who had undergone CCTA. We scored stair-step artifacts from 1 (severe) to 5 (none) and evaluated the effective dose in 53 patients with retrospective CCTA and 130 with prospective CCTA (PT 200 ms, n=32; PT 50 ms, n=98). Mean artifact scores were 4.3 in both retrospective and prospective CCTAs. However, statistically more arteries scored <3 (nonassessable) on prospective CCTA (P<0.001). Mean scores for prospective CCTA with 200- and 50-ms PT were 4.1 and 4.3, respectively (no significant difference). The radiation dose of prospective CCTA was reduced by 59.1% to 80.7%. Prospective CCTA reduces the radiation dose and allows diagnostic imaging in most cases but shows more nonevaluable artifacts than retrospective CCTA. Use of 50-ms instead of 200-ms PT appears to maintain image quality in patients with a mean HR <65 beats/min and HR instability of <5 beats/min. (author)

  10. Effects of over-the-counter sales restriction of antibiotics on substitution with medicines for symptoms relief of cold in Mexico and Brazil : time series analysis

    NARCIS (Netherlands)

    Santa Ana Tellez, Y.; Teeuwisse, A.K.; Leufkens, H.G.M.; Wirtz, Veronika J

    2016-01-01

    We evaluated changes in the use of non-steroidal anti-inflammatory drugs (NSAIDs), non-opioid analgesics and cough and cold medicines and its relation with the use of antibiotics after the over-the-counter (OTC) antibiotic sales restrictions in Mexico and Brazil. IMS Health provided retail quarterly

  11. An application of the time-step topological model for three-phase transformer no-load current calculation considering hysteresis

    International Nuclear Information System (INIS)

    Carrander, Claes; Mousavi, Seyed Ali; Engdahl, Göran

    2017-01-01

    In many transformer applications, it is necessary to have a core magnetization model that takes into account both magnetic and electrical effects. This becomes particularly important in three-phase transformers, where the zero-sequence impedance is generally high, and therefore affects the magnetization very strongly. In this paper, we demonstrate a time-step topological simulation method that uses a lumped-element approach to accurately model both the electrical and magnetic circuits. The simulation method is independent of the used hysteresis model. In this paper, a hysteresis model based on the first-order reversal-curve has been used. - Highlights: • A lumped-element method for modelling transformers i demonstrated. • The method can include hysteresis and arbitrarily complex geometries. • Simulation results for one power transformer are compared to measurements. • An analytical curve-fitting expression for static hysteresis loops is shown.

  12. Exshall: A Turkel-Zwas explicit large time-step FORTRAN program for solving the shallow-water equations in spherical coordinates

    Science.gov (United States)

    Navon, I. M.; Yu, Jian

    A FORTRAN computer program is presented and documented applying the Turkel-Zwas explicit large time-step scheme to a hemispheric barotropic model with constraint restoration of integral invariants of the shallow-water equations. We then proceed to detail the algorithms embodied in the code EXSHALL in this paper, particularly algorithms related to the efficiency and stability of T-Z scheme and the quadratic constraint restoration method which is based on a variational approach. In particular we provide details about the high-latitude filtering, Shapiro filtering, and Robert filtering algorithms used in the code. We explain in detail the various subroutines in the EXSHALL code with emphasis on algorithms implemented in the code and present the flowcharts of some major subroutines. Finally, we provide a visual example illustrating a 4-day run using real initial data, along with a sample printout and graphic isoline contours of the height field and velocity fields.

  13. A journey of a thousand miles begins with one small step - human agency, hydrological processes and time in socio-hydrology

    Science.gov (United States)

    Ertsen, M. W.; Murphy, J. T.; Purdue, L. E.; Zhu, T.

    2014-04-01

    When simulating social action in modeling efforts, as in socio-hydrology, an issue of obvious importance is how to ensure that social action by human agents is well-represented in the analysis and the model. Generally, human decision-making is either modeled on a yearly basis or lumped together as collective social structures. Both responses are problematic, as human decision-making is more complex and organizations are the result of human agency and cannot be used as explanatory forces. A way out of the dilemma of how to include human agency is to go to the largest societal and environmental clustering possible: society itself and climate, with time steps of years or decades. In the paper, another way out is developed: to face human agency squarely, and direct the modeling approach to the agency of individuals and couple this with the lowest appropriate hydrological level and time step. This approach is supported theoretically by the work of Bruno Latour, the French sociologist and philosopher. We discuss irrigation archaeology, as it is in this discipline that the issues of scale and explanatory force are well discussed. The issue is not just what scale to use: it is what scale matters. We argue that understanding the arrangements that permitted the management of irrigation over centuries requires modeling and understanding the small-scale, day-to-day operations and personal interactions upon which they were built. This effort, however, must be informed by the longer-term dynamics, as these provide the context within which human agency is acted out.

  14. Associations between the Objectively Measured Office Environment and Workplace Step Count and Sitting Time: Cross-Sectional Analyses from the Active Buildings Study.

    Science.gov (United States)

    Fisher, Abi; Ucci, Marcella; Smith, Lee; Sawyer, Alexia; Spinney, Richard; Konstantatou, Marina; Marmot, Alexi

    2018-06-01

    Office-based workers spend a large proportion of the day sitting and tend to have low overall activity levels. Despite some evidence that features of the external physical environment are associated with physical activity, little is known about the influence of the spatial layout of the internal environment on movement, and the majority of data use self-report. This study investigated associations between objectively-measured sitting time and activity levels and the spatial layout of office floors in a sample of UK office-based workers. Participants wore activPAL accelerometers for at least three consecutive workdays. Primary outcomes were steps and proportion of sitting time per working hour. Primary exposures were office spatial layout, which was objectively-measured by deriving key spatial variables: 'distance from each workstation to key office destinations', 'distance from participant's workstation to all other workstations', 'visibility of co-workers', and workstation 'closeness'. 131 participants from 10 organisations were included. Fifty-four per cent were female, 81% were white, and the majority had a managerial or professional role (72%) in their organisation. The average proportion of the working hour spent sitting was 0.7 (SD 0.15); participants took on average 444 (SD 210) steps per working hour. Models adjusted for confounders revealed significant negative associations between step count and distance from each workstation to all other office destinations (e.g., B = -4.66, 95% CI: -8.12, -1.12, p office destinations (e.g., B = -6.45, 95% CI: -11.88, -0.41, p office destinations the less they walked, suggesting that changing the relative distance between workstations and other destinations on the same floor may not be the most fruitful target for promoting walking and reducing sitting in the workplace. However, reported effect sizes were very small and based on cross-sectional analyses. The approaches developed in this study could be applied to other

  15. Computing the sensitivity of drag and lift in flow past a circular cylinder: Time-stepping versus self-consistent analysis

    Science.gov (United States)

    Meliga, Philippe

    2017-07-01

    We provide in-depth scrutiny of two methods making use of adjoint-based gradients to compute the sensitivity of drag in the two-dimensional, periodic flow past a circular cylinder (Re≲189 ): first, the time-stepping analysis used in Meliga et al. [Phys. Fluids 26, 104101 (2014), 10.1063/1.4896941] that relies on classical Navier-Stokes modeling and determines the sensitivity to any generic control force from time-dependent adjoint equations marched backwards in time; and, second, a self-consistent approach building on the model of Mantič-Lugo et al. [Phys. Rev. Lett. 113, 084501 (2014), 10.1103/PhysRevLett.113.084501] to compute semilinear approximations of the sensitivity to the mean and fluctuating components of the force. Both approaches are applied to open-loop control by a small secondary cylinder and allow identifying the sensitive regions without knowledge of the controlled states. The theoretical predictions obtained by time-stepping analysis reproduce well the results obtained by direct numerical simulation of the two-cylinder system. So do the predictions obtained by self-consistent analysis, which corroborates the relevance of the approach as a guideline for efficient and systematic control design in the attempt to reduce drag, even though the Reynolds number is not close to the instability threshold and the oscillation amplitude is not small. This is because, unlike simpler approaches relying on linear stability analysis to predict the main features of the flow unsteadiness, the semilinear framework encompasses rigorously the effect of the control on the mean flow, as well as on the finite-amplitude fluctuation that feeds back nonlinearly onto the mean flow via the formation of Reynolds stresses. Such results are especially promising as the self-consistent approach determines the sensitivity from time-independent equations that can be solved iteratively, which makes it generally less computationally demanding. We ultimately discuss the extent to

  16. Spectrum of Slip Processes on the Subduction Interface in a Continuum Framework Resolved by Rate-and State Dependent Friction and Adaptive Time Stepping

    Science.gov (United States)

    Herrendoerfer, R.; van Dinther, Y.; Gerya, T.

    2015-12-01

    To explore the relationships between subduction dynamics and the megathrust earthquake potential, we have recently developed a numerical model that bridges the gap between processes on geodynamic and earthquake cycle time scales. In a self-consistent, continuum-based framework including a visco-elasto-plastic constitutive relationship, cycles of megathrust earthquake-like ruptures were simulated through a purely slip rate-dependent friction, albeit with very low slip rates (van Dinther et al., JGR, 2013). In addition to much faster earthquakes, a range of aseismic slip processes operate at different time scales in nature. These aseismic processes likely accommodate a considerable amount of the plate convergence and are thus relevant in order to estimate the long-term seismic coupling and related hazard in subduction zones. To simulate and resolve this wide spectrum of slip processes, we innovatively implemented rate-and state dependent friction (RSF) and an adaptive time-stepping into our continuum framework. The RSF formulation, in contrast to our previous friction formulation, takes the dependency of frictional strength on a state variable into account. It thereby allows for continuous plastic yielding inside rate-weakening regions, which leads to aseismic slip. In contrast to the conventional RSF formulation, we relate slip velocities to strain rates and use an invariant formulation. Thus we do not require the a priori definition of infinitely thin, planar faults in a homogeneous elastic medium. With this new implementation of RSF, we succeed to produce consistent cycles of frictional instabilities. By changing the frictional parameter a, b, and the characteristic slip distance, we observe a transition from stable sliding to stick-slip behaviour. This transition is in general agreement with predictions from theoretical estimates of the nucleation size, thereby to first order validating our implementation. By incorporating adaptive time-stepping based on a

  17. Effects of Conjugate Gradient Methods and Step-Length Formulas on the Multiscale Full Waveform Inversion in Time Domain: Numerical Experiments

    Science.gov (United States)

    Liu, Youshan; Teng, Jiwen; Xu, Tao; Badal, José; Liu, Qinya; Zhou, Bing

    2017-05-01

    We carry out full waveform inversion (FWI) in time domain based on an alternative frequency-band selection strategy that allows us to implement the method with success. This strategy aims at decomposing the seismic data within partially overlapped frequency intervals by carrying out a concatenated treatment of the wavelet to largely avoid redundant frequency information to adapt to wavelength or wavenumber coverage. A pertinent numerical test proves the effectiveness of this strategy. Based on this strategy, we comparatively analyze the effects of update parameters for the nonlinear conjugate gradient (CG) method and step-length formulas on the multiscale FWI through several numerical tests. The investigations of up to eight versions of the nonlinear CG method with and without Gaussian white noise make clear that the HS (Hestenes and Stiefel in J Res Natl Bur Stand Sect 5:409-436, 1952), CD (Fletcher in Practical methods of optimization vol. 1: unconstrained optimization, Wiley, New York, 1987), and PRP (Polak and Ribière in Revue Francaise Informat Recherche Opertionelle, 3e Année 16:35-43, 1969; Polyak in USSR Comput Math Math Phys 9:94-112, 1969) versions are more efficient among the eight versions, while the DY (Dai and Yuan in SIAM J Optim 10:177-182, 1999) version always yields inaccurate result, because it overestimates the deeper parts of the model. The application of FWI algorithms using distinct step-length formulas, such as the direct method ( Direct), the parabolic search method ( Search), and the two-point quadratic interpolation method ( Interp), proves that the Interp is more efficient for noise-free data, while the Direct is more efficient for Gaussian white noise data. In contrast, the Search is less efficient because of its slow convergence. In general, the three step-length formulas are robust or partly insensitive to Gaussian white noise and the complexity of the model. When the initial velocity model deviates far from the real model or the

  18. Effect of selenization time on the structural and morphological properties of Cu(In,Ga)Se2 thin films absorber layers using two step growth process

    Science.gov (United States)

    Korir, Peter C.; Dejene, Francis B.

    2018-04-01

    In this work two step growth process was used to prepare Cu(In, Ga)Se2 thin film for solar cell applications. The first step involves deposition of Cu-In-Ga precursor films followed by the selenization process under vacuum using elemental selenium vapor to form Cu(In,Ga)Se2 film. The growth process was done at a fixed temperature of 515 °C for 45, 60 and 90 min to control film thickness and gallium incorporation into the absorber layer film. The X-ray diffraction (XRD) pattern confirms single-phase Cu(In,Ga)Se2 film for all the three samples and no secondary phases were observed. A shift in the diffraction peaks to higher 2θ (2 theta) values is observed for the thin films compared to that of pure CuInSe2. The surface morphology of the resulting film grown for 60 min was characterized by the presence of uniform large grain size particles, which are typical for device quality material. Photoluminescence spectra show the shifting of emission peaks to higher energies for longer duration of selenization attributed to the incorporation of more gallium into the CuInSe2 crystal structure. Electron probe microanalysis (EPMA) revealed a uniform distribution of the elements through the surface of the film. The elemental ratio of Cu/(In + Ga) and Se/Cu + In + Ga strongly depends on the selenization time. The Cu/In + Ga ratio for the 60 min film is 0.88 which is in the range of the values (0.75-0.98) for best solar cell device performances.

  19. Time required for partial pressure of arterial oxygen equilibration during mechanical ventilation after a step change in fractional inspired oxygen concentration.

    Science.gov (United States)

    Cakar, N; Tuŏrul, M; Demirarslan, A; Nahum, A; Adams, A; Akýncý, O; Esen, F; Telci, L

    2001-04-01

    To determine the time required for the partial pressure of arterial oxygen (PaO2) to reach equilibrium after a 0.20 increment or decrement in fractional inspired oxygen concentration (FIO2) during mechanical ventilation. A multi-disciplinary ICU in a university hospital. Twenty-five adult, non-COPD patients with stable blood gas values (PaO2/FIO2 > or = 180 on the day of the study) on pressure-controlled ventilation (PCV). Following a baseline PaO2 (PaO2b) measurement at FIO2 = 0.35, the FIO2 was increased to 0.55 for 30 min and then decreased to 0.35 without any other change in ventilatory parameters. Sequential blood gas measurements were performed at 3, 5, 7, 9, 11, 15, 20, 25 and 30 min in both periods. The PaO2 values measured at the 30th min after a step change in FIO2 (FIO2 = 0.55, PaO2[55] and FIO2 = 0.35, PaO2[35]) were accepted as representative of the equilibrium values for PaO2. Each patient's rise and fall in PaO2 over time, PaO2(t), were fitted to the following respective exponential equations: PaO2b + (PaO2[55]-PaO2b)(1-e-kt) and PaO2[55] + (PaO2[35]-PaO2[55])(e-kt) where "t" refers to time, PaO2[55] and PaO2[35] are the final PaO2 values obtained at a new FIO2 of 0.55 and 0.35, after a 0.20 increment and decrement in FIO2, respectively. Time constant "k" was determined by a non-linear fitting curve and 90% oxygenation times were defined as the time required to reach 90% of the final equilibrated PaO2 calculated by using the non-linear fitting curves. Time constant values for the rise and fall periods were 1.01 +/- 0.71 min-1, 0.69 +/- 0.42 min-1, respectively, and 90% oxygenation times for rises and falls in PaO2 periods were 4.2 +/- 4.1 min-1 and 5.5 +/- 4.8 min-1, respectively. There was no significant difference between the rise and fall periods for the two parameters (p > 0.05). We conclude that in stable patients ventilated with PCV, after a step change in FIO2 of 0.20, 5-10 min will be adequate for obtaining a blood gas sample to measure a Pa

  20. Two Step Acceleration Process of Electrons in the Outer Van Allen Radiation Belt by Time Domain Electric Field Bursts and Large Amplitude Chorus Waves

    Science.gov (United States)

    Agapitov, O. V.; Mozer, F.; Artemyev, A.; Krasnoselskikh, V.; Lejosne, S.

    2014-12-01

    A huge number of different non-linear structures (double layers, electron holes, non-linear whistlers, etc) have been observed by the electric field experiment on the Van Allen Probes in conjunction with relativistic electron acceleration in the Earth's outer radiation belt. These structures, found as short duration (~0.1 msec) quasi-periodic bursts of electric field in the high time resolution electric field waveform, have been called Time Domain Structures (TDS). They can quite effectively interact with radiation belt electrons. Due to the trapping of electrons into these non-linear structures, they are accelerated up to ~10 keV and their pitch angles are changed, especially for low energies (˜1 keV). Large amplitude electric field perturbations cause non-linear resonant trapping of electrons into the effective potential of the TDS and these electrons are then accelerated in the non-homogeneous magnetic field. These locally accelerated electrons create the "seed population" of several keV electrons that can be accelerated by coherent, large amplitude, upper band whistler waves to MeV energies in this two step acceleration process. All the elements of this chain acceleration mechanism have been observed by the Van Allen Probes.

  1. Applicability of a two-step laser desorption-ionization aerosol time-of-flight mass spectrometer for determination of chemical composition of ultrafine aerosol particles

    Energy Technology Data Exchange (ETDEWEB)

    Laitinen, T.

    2013-11-01

    This thesis is based on the construction of a two-step laser desorption-ionization aerosol time-of-flight mass spectrometer (laser AMS), which is capable of measuring 10 to 50 nm aerosol particles collected from urban and rural air at-site and in near real time. The operation and applicability of the instrument was tested with various laboratory measurements, including parallel measurements with filter collection/chromatographic analysis, and then in field experiments in urban environment and boreal forest. Ambient ultrafine aerosol particles are collected on a metal surface by electrostatic precipitation and introduced to the time-of-flight mass spectrometer (TOF-MS) with a sampling valve. Before MS analysis particles are desorbed from the sampling surface with an infrared laser and ionized with a UV laser. The formed ions are guided to the TOF-MS by ion transfer optics, separated according to their m/z ratios, and detected with a micro channel plate detector. The laser AMS was used in urban air studies to quantify the carbon cluster content in 50 nm aerosol particles. Standards for the study were produced from 50 nm graphite particles, suspended in toluene, with 72 hours of high power sonication. The results showed the average amount of carbon clusters (winter 2012, Helsinki, Finland) in 50 nm particles to be 7.2% per sample. Several fullerenes/fullerene fragments were detected during the measurements. In boreal forest measurements, the laser AMS was capable of detecting several different organic species in 10 to 50 nm particles. These included nitrogen-containing compounds, carbon clusters, aromatics, aliphatic hydrocarbons, and oxygenated hydrocarbons. A most interesting event occurred during the boreal forest measurements in spring 2011 when the chemistry of the atmosphere clearly changed during snow melt. On that time concentrations of laser AMS ions m/z 143 and 185 (10 nm particles) increased dramatically. Exactly at the same time, quinoline concentrations

  2. Diablo 2.0: A modern DNS/LES code for the incompressible NSE leveraging new time-stepping and multigrid algorithms

    Science.gov (United States)

    Cavaglieri, Daniele; Bewley, Thomas; Mashayek, Ali

    2015-11-01

    We present a new code, Diablo 2.0, for the simulation of the incompressible NSE in channel and duct flows with strong grid stretching near walls. The code leverages the fractional step approach with a few twists. New low-storage IMEX (implicit-explicit) Runge-Kutta time-marching schemes are tested which are superior to the traditional and widely-used CN/RKW3 (Crank-Nicolson/Runge-Kutta-Wray) approach; the new schemes tested are L-stable in their implicit component, and offer improved overall order of accuracy and stability with, remarkably, similar computational cost and storage requirements. For duct flow simulations, our new code also introduces a new smoother for the multigrid solver for the pressure Poisson equation. The classic approach, involving alternating-direction zebra relaxation, is replaced by a new scheme, dubbed tweed relaxation, which achieves the same convergence rate with roughly half the computational cost. The code is then tested on the simulation of a shear flow instability in a duct, a classic problem in fluid mechanics which has been the object of extensive numerical modelling for its role as a canonical pathway to energetic turbulence in several fields of science and engineering.

  3. A 1 MHz BW 34.2 fJ/step Continuous Time Delta Sigma Modulator With an Integrated Mixer for Cardiac Ultrasound.

    Science.gov (United States)

    Kaald, Rune; Eggen, Trym; Ytterdal, Trond

    2017-02-01

    Fully digitized 2D ultrasound transducer arrays require one ADC per channel with a beamforming architecture consuming low power. We give design considerations for per-channel digitization and beamforming, and present the design and measurements of a continuous time delta-sigma modulator (CTDSM) for cardiac ultrasound applications. By integrating a mixer into the modulator frontend, the phase and frequency of the input signal can be shifted, thereby enabling both improved conversion efficiency and narrowband beamforming. To minimize the power consumption, we propose an optimization methodology using a simulated annealing framework combined with a C++ simulator solving linear electrical networks. The 3rd order single-bit feedback type modulator, implemented in a 65 nm CMOS process, achieves an SNR/SNDR of 67.8/67.4 dB across 1 MHz bandwidth consuming 131 [Formula: see text] of power. The achieved figure of merit of 34.2 fJ/step is comparable with state-of-the-art feedforward type multi-bit designs. We further demonstrate the influence to the dynamic range when performing dynamic receive beamforming on recorded delta-sigma modulated bit-stream sequences.

  4. Application of stepping motor

    International Nuclear Information System (INIS)

    1980-10-01

    This book is divided into three parts, which is about practical using of stepping motor. The first part has six chapters. The contents of the first part are about stepping motor, classification of stepping motor, basic theory og stepping motor, characteristic and basic words, types and characteristic of stepping motor in hybrid type and basic control of stepping motor. The second part deals with application of stepping motor with hardware of stepping motor control, stepping motor control by microcomputer and software of stepping motor control. The last part mentions choice of stepping motor system, examples of stepping motor, measurement of stepping motor and practical cases of application of stepping motor.

  5. Guidance as to restrictions on exposures to time varying electromagnetic fields and the 1988 recommendations of the International Non-Ionizing Radiation Committee

    CERN Document Server

    Dennis, J A

    1989-01-01

    Under a direction from the Health Ministers, NRPB is required to advise on the acceptability to the United Kingdom of standards recommended or proposed by certain international bodies relating to protection from both ionising radiations and non-ionising electromagnetic radiations. This document contains the Board's advice in response to guidelines recommended by the International Non-Ionizing Radiation Committee (INIRC) on limiting exposures to electromagnetic fields in the frequency range 100 kHz to 300 GHz (Health Physics, 54, 115 (1988)). The Board's advice, however, extends over all frequencies up to 300 GHz. It has been prepared after considering advice from the Medical Research Council and responses to consultative documents published by the Board in 1982 and 1986. The Board's advice is intended to protect against the thermal effects of the absorption of electromagnetic energy and against the possibilities of electric shock and burn. It consists of a set of basic restrictions both on the average rate of...

  6. Time for a re-evaluation of mammography in the young? Results of an audit of mammography in women younger than 40 in a resource restricted environment.

    Science.gov (United States)

    Taylor, Liezel; Basro, Sarinah; Apffelstaedt, Justus P; Baatjes, Karin

    2011-08-01

    Mammography in younger women is considered to be of limited value. In a resource restricted environment without access to magnetic resonance imaging (MRI) and with a high incidence of breast cancer in the young, mammography remains an important diagnostic tool. Recent technical advances and better regulation of mammography make a reassessment of its value in these conditions necessary. Data of all the mammograms performed at a tertiary hospital and private breast clinic between January 2003 and July 2009 in women less than 40 years of age were collected. Indications were the presence of a mass, follow-up after primary cancer therapy, and screening for patients perceived at high risk due to a family history or the presence of atypical hyperplasia. Data acquired were as follows: Demographics, prior breast surgery, indication for mammography, outcome of mammography, diagnostic procedures, and their results. Of 2,167 mammograms, 393 were performed for a palpable mass, diagnostic mammography. In these, the overall cancer detection rate was 40%. If the mammography was reported as breast imaging reporting and data system (BIRADS(®)) 5 versus BIRADS(®) 3 and 4 versus BIRADS(®) 1 and 2, a final diagnosis of malignancy was established in 96, 48, and 5%, respectively. Of 367 mammograms done for the follow-up after primary treatment of breast cancer, seven cancers were diagnosed for a detection rate of 1.9%. Of 1,312 mammograms performed for screening, the recall rate was 4%; the biopsy rate 2%, and the cancer diagnosis rate 3/1,000 examinations. In contrast to past series, this series has shown that recent advances in mammography have made it a useful tool in the management of breast problems in young women, notably in a resource-restricted environment. Women for screening should be selected carefully.

  7. A sensitive one-step real-time PCR for detection of avian influenza viruses using a MGB probe and an internal positive control

    Directory of Open Access Journals (Sweden)

    Delogu Mauro

    2006-05-01

    Full Text Available Abstract Background Avian influenza viruses (AIVs are endemic in wild birds and their introduction and conversion to highly pathogenic avian influenza virus in domestic poultry is a cause of serious economic losses as well as a risk for potential transmission to humans. The ability to rapidly recognise AIVs in biological specimens is critical for limiting further spread of the disease in poultry. The advent of molecular methods such as real time polymerase chain reaction has allowed improvement of detection methods currently used in laboratories, although not all of these methods include an Internal Positive Control (IPC to monitor for false negative results. Therefore we developed a one-step reverse transcription real time PCR (RRT-PCR with a Minor Groove Binder (MGB probe for the detection of different subtypes of AIVs. This technique also includes an IPC. Methods RRT-PCR was developed using an improved TaqMan technology with a MGB probe to detect AI from reference viruses. Primers and probe were designed based on the matrix gene sequences from most animal and human A influenza virus subtypes. The specificity of RRT-PCR was assessed by detecting influenza A virus isolates belonging to subtypes from H1–H13 isolated in avian, human, swine and equine hosts. The analytical sensitivity of the RRT-PCR assay was determined using serial dilutions of in vitro transcribed matrix gene RNA. The use of a rodent RNA as an IPC in order not to reduce the efficiency of the assay was adopted. Results The RRT-PCR assay is capable to detect all tested influenza A viruses. The detection limit of the assay was shown to be between 5 and 50 RNA copies per reaction and the standard curve demonstrated a linear range from 5 to 5 × 108 copies as well as excellent reproducibility. The analytical sensitivity of the assay is 10–100 times higher than conventional RT-PCR. Conclusion The high sensitivity, rapidity, reproducibility and specificity of the AIV RRT-PCR with

  8. When the Brain Takes 'BOLD' Steps: Real-Time fMRI Neurofeedback Can Further Enhance the Ability to Gradually Self-regulate Regional Brain Activation.

    Science.gov (United States)

    Sorger, Bettina; Kamp, Tabea; Weiskopf, Nikolaus; Peters, Judith Caroline; Goebel, Rainer

    2018-05-15

    Brain-computer interfaces (BCIs) based on real-time functional magnetic resonance imaging (rtfMRI) are currently explored in the context of developing alternative (motor-independent) communication and control means for the severely disabled. In such BCI systems, the user encodes a particular intention (e.g., an answer to a question or an intended action) by evoking specific mental activity resulting in a distinct brain state that can be decoded from fMRI activation. One goal in this context is to increase the degrees of freedom in encoding different intentions, i.e., to allow the BCI user to choose from as many options as possible. Recently, the ability to voluntarily modulate spatial and/or temporal blood oxygenation level-dependent (BOLD)-signal features has been explored implementing different mental tasks and/or different encoding time intervals, respectively. Our two-session fMRI feasibility study systematically investigated for the first time the possibility of using magnitudinal BOLD-signal features for intention encoding. Particularly, in our novel paradigm, participants (n=10) were asked to alternately self-regulate their regional brain-activation level to 30%, 60% or 90% of their maximal capacity by applying a selected activation strategy (i.e., performing a mental task, e.g., inner speech) and modulation strategies (e.g., using different speech rates) suggested by the experimenters. In a second step, we tested the hypothesis that the additional availability of feedback information on the current BOLD-signal level within a region of interest improves the gradual-self regulation performance. Therefore, participants were provided with neurofeedback in one of the two fMRI sessions. Our results show that the majority of the participants were able to gradually self-regulate regional brain activation to at least two different target levels even in the absence of neurofeedback. When provided with continuous feedback on their current BOLD-signal level, most

  9. Step out - Step in Sequencing Games

    NARCIS (Netherlands)

    Musegaas, M.; Borm, P.E.M.; Quant, M.

    2014-01-01

    In this paper a new class of relaxed sequencing games is introduced: the class of Step out - Step in sequencing games. In this relaxation any player within a coalition is allowed to step out from his position in the processing order and to step in at any position later in the processing order.

  10. Step out-step in sequencing games

    NARCIS (Netherlands)

    Musegaas, Marieke; Borm, Peter; Quant, Marieke

    2015-01-01

    In this paper a new class of relaxed sequencing games is introduced: the class of Step out–Step in sequencing games. In this relaxation any player within a coalition is allowed to step out from his position in the processing order and to step in at any position later in the processing order. First,

  11. Influence of time restriction, 20 minutes and 94.6 months, of visual information on angular displacement during the sit-to-stand (STS) task in three planes.

    Science.gov (United States)

    Aylar, Mozhgan Faraji; Firouzi, Faramarz; Araghi, Mandana Rahnama

    2016-12-01

    [Purpose] The purpose of this investigation was to assess whether or not restriction of visual information influences the kinematics of sit-to-stand (STS) performance in children. [Subjects and Methods] Five girls with congenital blindness (CB) and ten healthy girls with no visual impairments were randomly selected. The girls with congenital blindness were placed in one group and the ten girls with no visual impairments were divided into two groups of five, control and treatment groups. The participants in the treatment group were asked to close their eyes (EC) for 20 minutes before the STS test, whereas those in the control group kept their eyes open (EO). The performance of the participants in all three groups was measured using a motion capture system and two force plates. [Results] The results show that the constraint duration of visual sensory information affected the range of motion (ROM), the excursion of the dominant side ankle, and the ROM of the dominant side knee in the EC group. However, only ankle excursion on the non-dominant side was affected in the CB group, and this was only observed in the sagittal plane. [Conclusion] These results indicate that visual memory does not affect the joint angles in the frontal and transverse planes. Moreover, all of the participants could perform the STS transition without falling, indicating; the participants performed the STS maneuver correctly in all planes except the sagittal one.

  12. Evaluation of a Rapid One-step Real-time PCR Method as a High-throughput Screening for Quantification of Hepatitis B Virus DNA in a Resource-limited Setting.

    Science.gov (United States)

    Rashed-Ul Islam, S M; Jahan, Munira; Tabassum, Shahina

    2015-01-01

    Virological monitoring is the best predictor for the management of chronic hepatitis B virus (HBV) infections. Consequently, it is important to use the most efficient, rapid and cost-effective testing systems for HBV DNA quantification. The present study compared the performance characteristics of a one-step HBV polymerase chain reaction (PCR) vs the two-step HBV PCR method for quantification of HBV DNA from clinical samples. A total of 100 samples consisting of 85 randomly selected samples from patients with chronic hepatitis B (CHB) and 15 samples from apparently healthy individuals were enrolled in this study. Of the 85 CHB clinical samples tested, HBV DNA was detected from 81% samples by one-step PCR method with median HBV DNA viral load (VL) of 7.50 × 10 3 lU/ml. In contrast, 72% samples were detected by the two-step PCR system with median HBV DNA of 3.71 × 10 3 lU/ml. The one-step method showed strong linear correlation with two-step PCR method (r = 0.89; p Tabassum S. Evaluation of a Rapid One-step Real-time PCR Method as a High-throughput Screening for Quantification of Hepatitis B Virus DNA in a Resource-limited Setting. Euroasian J Hepato-Gastroenterol 2015;5(1):11-15.

  13. Restrictions and Proportionality

    DEFF Research Database (Denmark)

    Werlauff, Erik

    2009-01-01

    The article discusses three central aspects of the freedoms under European Community law, namely 1) the prohibition against restrictions as an important extension of the prohibition against discrimination, 2) a prohibition against exit restrictions which is just as important as the prohibition...... against host country restrictions, but which is often not recognised to the same extent by national law, and 3) the importance of also identifying and recognising an exit restriction, so that it is possible to achieve the required test of appropriateness and proportionality in relation to the rule...

  14. What Do We Know about Risk Factors for Fetal Growth Restriction in Africa at the Time of Sustainable Development Goals? A Scoping Review.

    Science.gov (United States)

    Accrombessi, Manfred; Zeitlin, Jennifer; Massougbodji, Achille; Cot, Michel; Briand, Valérie

    2018-03-01

    The reduction in the under-5 year mortality rate to at least as low as 25 per 1000 livebirths by 2030 has been implemented as one of the new Sustainable Development Goals. Fetal growth restriction (FGR) is one of the most important determinants of infant mortality in developing countries. In this review, we assess the extent of the literature and summarize its findings on the main preventable factors of FGR in Africa. A scoping review was conducted using the Arksey and O'Malley framework. Five bibliographic databases and grey literature were used to identify studies assessing at least one risk factor for FGR. Aggregate risk estimates for the main factors associated with FGR were calculated. Forty-five of a total of 671 articles were selected for the review. The prevalence of FGR varied between 2.6 and 59.2% according to both the African region and the definition of FGR. The main preventable factors reported were a low maternal nutritional status (aggrerate odds ratio [OR]: 2.28, 95% confidence interval [CI] 1.59, 3.25), HIV infection (aOR 1.86, 95% CI 1.38, 2.50), malaria (aOR 1.95, 95% CI 1.04, 3.66), and gestational hypertension (aOR 2.61, 95% CI 2.42, 2.82). FGR is, to a large extent, preventable through existing efficacious interventions dedicated to malaria, HIV and nutrition. Further studies are still needed to assess the influence of risk factors most commonly documented in high-income countries. Improving research on FGR in Africa requires a consensual and standardized definition of FGR-for a higher comparability-between studies and settings. © 2017 John Wiley & Sons Ltd.

  15. Determination of genotype differences through restriction ...

    African Journals Online (AJOL)

    Tyrosinase gene or C locus has long been implicated in the coat colour determination. This gene a copper-containing enzyme located on chromosome 11q14.3 is expressed in melanocytes and controls the major steps in pigment production. In camel, C locus a restriction site provoked by the T variant of the mutation was ...

  16. Restricting wolves risks escape

    Science.gov (United States)

    Mech, L. David; Ballard, Warren; Bangs, Ed; Ream, Bob

    2010-01-01

    Implementing the proposal set forth by Licht and colleagues (BioScience 60: 147–153) requires restricting wolves to tiny "islands," areas that are magnitudes smaller than the ranges of most wolf populations. Wolves naturally have large ranges; restricting their spatial needs increases the risk of wolves escaping, exacerbating public relations and political and legal problems.

  17. On the Convexity of Step out - Step in Sequencing Games

    NARCIS (Netherlands)

    Musegaas, Marieke; Borm, Peter; Quant, Marieke

    2016-01-01

    The main result of this paper is the convexity of Step out - Step in (SoSi) sequencing games, a class of relaxed sequencing games first analyzed by Musegaas, Borm, and Quant (2015). The proof makes use of a polynomial time algorithm determining the value and an optimal processing order for an

  18. Detection of live Salmonella enterica in fresh-cut vegetables by a TaqMan-based one-step reverse transcription real-time PCR.

    Science.gov (United States)

    Miao, Y J; Xiong, G T; Bai, M Y; Ge, Y; Wu, Z F

    2018-05-01

    Fresh-cut produce is at greater risk of Salmonella contamination. Detection and early warning systems play an important role in reducing the dissemination of contaminated products. One-step Reverse Transcription Polymerase Chain Reaction (RT-qPCR) targeting Salmonella tmRNA with or without a 6-h enrichment was evaluated for the detection of Salmonella in fresh-cut vegetables after 6-h storage. LOD of one-step RT-qPCR was 1·0 CFU per ml (about 100 copies tmRNA per ml) by assessed 10-fold serially diluted RNA from 10 6 CFU per ml bacteria culture. Then, one-step RT-qPCR assay was applied to detect viable Salmonella cells in 14 fresh-cut vegetables after 6-h storage. Without enrichment, this assay could detect 10 CFU per g for fresh-cut lettuce, cilantro, spinach, cabbage, Chinese cabbage and bell pepper, and 10 2 CFU per g for other vegetables. With a 6-h enrichment, this assay could detect 10 CFU per g for all fresh-cut vegetables used in this study. Moreover, this assay was able to discriminate viable cells from dead cells. This rapid detection assay may provide potential processing control and early warning method in fresh-cut vegetable processing to strengthen food safety assurance. Significance and Impact of the Study: Fresh-cut produce is at greater risk of Salmonella contamination. Rapid detection methods play an important role in reducing the dissemination of contaminated products. One-step RT-qPCR assay used in this study could detect 10 CFU per g Salmonella for 14 fresh-cut vegetables with a 6-h short enrichment. Moreover, this assay was able to discriminate viable cells from dead cells. This rapid detection assay may provide potential processing control and early warning method in fresh-cut vegetable processing to strengthen food safety assurance. © 2018 The Society for Applied Microbiology.

  19. Timeliness of recording in the Clinical Practice Research Datalink (CPRD – an initial step in the implementation of near real-time vaccine safety surveillance

    Directory of Open Access Journals (Sweden)

    Andreia Leite

    2017-04-01

    This work shows that most diagnoses examined were recorded with a delay of ≤30 days, making NRTVSS possible. The distribution of the delays was condition-specific and the weekly delay distribution could be used to adjust for delays in the NRTVSS analysis. CPRD can be a viable data source to use in this kind of analysis; next steps will include trial implementation of the system using these data.

  20. Assessing restrictiveness of national alcohol marketing policies.

    Science.gov (United States)

    Esser, Marissa B; Jernigan, David H

    2014-01-01

    To develop an approach for monitoring national alcohol marketing policies globally, an area of the World Health Organization's (WHO) Global Alcohol Strategy. Data on restrictiveness of alcohol marketing policies came from the 2002 and 2008 WHO Global Surveys on Alcohol and Health. We included four scales in a sensitivity analysis to determine optimal weights to score countries on their marketing policies and applied the selected scale to assess national marketing policy restrictiveness. Nearly, 36% of countries had no marketing restrictions. The overall restrictiveness levels were not significantly different between 2002 and 2008. The number of countries with strict marketing regulations did not differ across years. This method of monitoring alcohol marketing restrictiveness helps track progress towards implementing WHO'S Global Alcohol Strategy. Findings indicate a consistent lack of restrictive policies over time, making this a priority area for national and global action. © The Author 2014. Medical Council on Alcohol and Oxford University Press. All rights reserved.

  1. Focal cryotherapy: step by step technique description

    Directory of Open Access Journals (Sweden)

    Cristina Redondo

    Full Text Available ABSTRACT Introduction and objective: Focal cryotherapy emerged as an efficient option to treat favorable and localized prostate cancer (PCa. The purpose of this video is to describe the procedure step by step. Materials and methods: We present the case of a 68 year-old man with localized PCa in the anterior aspect of the prostate. Results: The procedure is performed under general anesthesia, with the patient in lithotomy position. Briefly, the equipment utilized includes the cryotherapy console coupled with an ultrasound system, argon and helium gas bottles, cryoprobes, temperature probes and an urethral warming catheter. The procedure starts with a real-time trans-rectal prostate ultrasound, which is used to outline the prostate, the urethra and the rectal wall. The cryoprobes are pretested and placed in to the prostate through the perineum, following a grid template, along with the temperature sensors under ultrasound guidance. A cystoscopy confirms the right positioning of the needles and the urethral warming catheter is installed. Thereafter, the freeze sequence with argon gas is started, achieving extremely low temperatures (-40°C to induce tumor cell lysis. Sequentially, the thawing cycle is performed using helium gas. This process is repeated one time. Results among several series showed a biochemical disease-free survival between 71-93% at 9-70 month- follow-up, incontinence rates between 0-3.6% and erectile dysfunction between 0-42% (1–5. Conclusions: Focal cryotherapy is a feasible procedure to treat anterior PCa that may offer minimal morbidity, allowing good cancer control and better functional outcomes when compared to whole-gland treatment.

  2. Group sequential designs for stepped-wedge cluster randomised trials.

    Science.gov (United States)

    Grayling, Michael J; Wason, James Ms; Mander, Adrian P

    2017-10-01

    The stepped-wedge cluster randomised trial design has received substantial attention in recent years. Although various extensions to the original design have been proposed, no guidance is available on the design of stepped-wedge cluster randomised trials with interim analyses. In an individually randomised trial setting, group sequential methods can provide notable efficiency gains and ethical benefits. We address this by discussing how established group sequential methodology can be adapted for stepped-wedge designs. Utilising the error spending approach to group sequential trial design, we detail the assumptions required for the determination of stepped-wedge cluster randomised trials with interim analyses. We consider early stopping for efficacy, futility, or efficacy and futility. We describe first how this can be done for any specified linear mixed model for data analysis. We then focus on one particular commonly utilised model and, using a recently completed stepped-wedge cluster randomised trial, compare the performance of several designs with interim analyses to the classical stepped-wedge design. Finally, the performance of a quantile substitution procedure for dealing with the case of unknown variance is explored. We demonstrate that the incorporation of early stopping in stepped-wedge cluster randomised trial designs could reduce the expected sample size under the null and alternative hypotheses by up to 31% and 22%, respectively, with no cost to the trial's type-I and type-II error rates. The use of restricted error maximum likelihood estimation was found to be more important than quantile substitution for controlling the type-I error rate. The addition of interim analyses into stepped-wedge cluster randomised trials could help guard against time-consuming trials conducted on poor performing treatments and also help expedite the implementation of efficacious treatments. In future, trialists should consider incorporating early stopping of some kind into

  3. A Compact Tandem Two-Step Laser Time-of-Flight Mass Spectrometer for In Situ Analysis of Non-Volatile Organics on Planetary Surfaces

    Science.gov (United States)

    Getty, Stephanie A.; Brinckerhoff, William B.; Li, Xiang; Elsila, Jamie; Cornish, Timothy; Ecelberger, Scott; Wu, Qinghao; Zare, Richard

    2014-01-01

    Two-step laser desorption mass spectrometry is a well suited technique to the analysis of high priority classes of organics, such as polycyclic aromatic hydrocarbons, present in complex samples. The use of decoupled desorption and ionization laser pulses allows for sensitive and selective detection of structurally intact organic species. We have recently demonstrated the implementation of this advancement in laser mass spectrometry in a compact, flight-compatible instrument that could feasibly be the centerpiece of an analytical science payload as part of a future spaceflight mission to a small body or icy moon.

  4. Time-resolved measurements of laser-induced diffusion of CO molecules on stepped Pt(111)-surfaces; Zeitaufgeloeste Untersuchung der laser-induzierten Diffusion von CO-Molekuelen auf gestuften Pt(111)-Oberflaechen

    Energy Technology Data Exchange (ETDEWEB)

    Lawrenz, M.

    2007-10-30

    In the present work the dynamics of CO-molecules on a stepped Pt(111)-surface induced by fs-laser pulses at low temperatures was studied by using laser spectroscopy. In the first part of the work, the laser-induced diffusion for the CO/Pt(111)-system could be demonstrated and modelled successfully for step diffusion. At first, the diffusion of CO-molecules from the step sites to the terrace sites on the surface was traced. The experimentally discovered energy transfer time of 500 fs for this process confirms the assumption of an electronically induced process. In the following it was explained how the experimental results were modelled. A friction coefficient which depends on the electron temperature yields a consistent model, whereas for the understanding of the fluence dependence and time-resolved measurements parallel the same set of parameters was used. Furthermore, the analysis was extended to the CO-terrace diffusion. Small coverages of CO were adsorbed to the terraces and the diffusion was detected as the temporal evolution of the occupation of the step sites acting as traps for the diffusing molecules. The additional performed two-pulse correlation measurements also indicate an electronically induced process. At the substrate temperature of 40 K the cross-correlation - where an energy transfer time of 1.8 ps was extracted - suggests also an electronically induced energy transfer mechanism. Diffusion experiments were performed for different substrate temperatures. (orig.)

  5. Restricted DCJ-indel model: sorting linear genomes with DCJ and indels

    Science.gov (United States)

    2012-01-01

    Background The double-cut-and-join (DCJ) is a model that is able to efficiently sort a genome into another, generalizing the typical mutations (inversions, fusions, fissions, translocations) to which genomes are subject, but allowing the existence of circular chromosomes at the intermediate steps. In the general model many circular chromosomes can coexist in some intermediate step. However, when the compared genomes are linear, it is more plausible to use the so-called restricted DCJ model, in which we proceed the reincorporation of a circular chromosome immediately after its creation. These two consecutive DCJ operations, which create and reincorporate a circular chromosome, mimic a transposition or a block-interchange. When the compared genomes have the same content, it is known that the genomic distance for the restricted DCJ model is the same as the distance for the general model. If the genomes have unequal contents, in addition to DCJ it is necessary to consider indels, which are insertions and deletions of DNA segments. Linear time algorithms were proposed to compute the distance and to find a sorting scenario in a general, unrestricted DCJ-indel model that considers DCJ and indels. Results In the present work we consider the restricted DCJ-indel model for sorting linear genomes with unequal contents. We allow DCJ operations and indels with the following constraint: if a circular chromosome is created by a DCJ, it has to be reincorporated in the next step (no other DCJ or indel can be applied between the creation and the reincorporation of a circular chromosome). We then develop a sorting algorithm and give a tight upper bound for the restricted DCJ-indel distance. Conclusions We have given a tight upper bound for the restricted DCJ-indel distance. The question whether this bound can be reduced so that both the general and the restricted DCJ-indel distances are equal remains open. PMID:23281630

  6. Apparatus for facilitating the servicing of inverted canned pump motors having limited access space and restricted access time especially in nuclear power plants

    International Nuclear Information System (INIS)

    Matusz, J.M.

    1991-01-01

    This patent describes a service apparatus for one or more inverted canned motor pumps installed above a floor and beneath a steam generator in a nuclear or fossil power plant with limited access space and limited access time at least in the case of nuclear power plants, each of the canned motor pumps having a pump casing and a depending motor having a flange secured to a pump casing flange by tensioned studs with tightened nuts. It comprises a maintenance cart having a height greater than the height of the motor beneath the motor flange and further having a generally U-shaped frame means with an open vertical side that permits the cart to be moved horizontally such that the cart frame means can be moved under the pump casing to surround the depending motor; actuator means supported by the cart frame means and having translating arm means engageable with support means on the motor; means for operating the translating arm means to support, raise and lower the motor; means supported by the frame means to support the motor flange prior to raising the motor to its installed position and after the motor has been released from its installed position and lowered to the cart; work platform means provided on the cart frame means at an elevation beneath the motor flange elevation; and roller means provided on the bottom of the cart frame means to facilitate horizontal cart movement along the floor

  7. Timing of Indonesian Gateway Restriction Between 4.0 and 2.8 Ma and its Impact on Indian Ocean Surface Waters Based on Calcareous Nannoplankton Assemblages

    Science.gov (United States)

    Auer, G.; De Vleeschouwer, D.; Groeneveld, J.; Bogus, K.; Henderiks, J.; Castañeda, I. S.; Expedition 356 Scientists, I.

    2017-12-01

    The Early Pliocene is characterized by a fundamental reorganization of Earth's climate. In particular, the ongoing constriction of the Indonesian Gateway (IG) around 4.0 - 3.0 Ma is commonly evoked cause for these climatic changes (Christensen et al., 2017; De Schepper et al., 2014; Karas et al., 2009; 2017). The constriction of the IG, caused by the northward movement of Australia and related uplift of Indonesia, had major effects on global climate and may have contributed to Northern Hemisphere cooling via complex atmospheric and oceanographic teleconnections. Untangling the exact timing of IG constriction is thus critical for resolving the mechanisms driving Earth's climatic evolution during the Pliocene. Here we present high-resolution reconstructions of surface water conditions and IG connectivity using calcareous nannoplankton (CNP) assemblages between 4.0 and 2.8 Ma at Site U1463 (18°59'S, 117°37'E; IODP Expedition 356). Located on the Northwest Shelf (NWS) of Australia, the site lies directly in the path of the upper branch of the Leeuwin-Holloway current, making it an ideal location to study Pliocene IG dynamics and their influence on the eastern Indian Ocean. Using modern analogue based interpretation of CNP assemblages, in combination with an independent orbitally tuned age model, shows a change in surface water conditions along the NWS 3.8 Ma recognizable by a decrease in tropical taxa like Umbilicosphaera sibogae and Sphenolithus spp. Subsequently, a shift from Gephyrocapsa sp. to Reticulofenestra sp. dominated CNP assemblages and the increase of mesotrophic CNP taxa (e.g. Umbilicosphaera jafari; Helicosphaera spp.), suggests that warm, stratified, oligotrophic (i.e. tropical) waters were replaced by cooler, more turbulent, and less saline waters by 3.8 - 3.6 Ma. We relate this switch in dominant water masses to changes in IG geometry delivering relatively cooler and fresher waters from northern Pacific sources to the NWS. The abundance of

  8. Biomechanical influences on balance recovery by stepping.

    Science.gov (United States)

    Hsiao, E T; Robinovitch, S N

    1999-10-01

    Stepping represents a common means for balance recovery after a perturbation to upright posture. Yet little is known regarding the biomechanical factors which determine whether a step succeeds in preventing a fall. In the present study, we developed a simple pendulum-spring model of balance recovery by stepping, and used this to assess how step length and step contact time influence the effort (leg contact force) and feasibility of balance recovery by stepping. We then compared model predictions of step characteristics which minimize leg contact force to experimentally observed values over a range of perturbation strengths. At all perturbation levels, experimentally observed step execution times were higher than optimal, and step lengths were smaller than optimal. However, the predicted increase in leg contact force associated with these deviations was substantial only for large perturbations. Furthermore, increases in the strength of the perturbation caused subjects to take larger, quicker steps, which reduced their predicted leg contact force. We interpret these data to reflect young subjects' desire to minimize recovery effort, subject to neuromuscular constraints on step execution time and step length. Finally, our model predicts that successful balance recovery by stepping is governed by a coupling between step length, step execution time, and leg strength, so that the feasibility of balance recovery decreases unless declines in one capacity are offset by enhancements in the others. This suggests that one's risk for falls may be affected more by small but diffuse neuromuscular impairments than by larger impairment in a single motor capacity.

  9. Internship guide : Work placements step by step

    NARCIS (Netherlands)

    Haag, Esther

    2013-01-01

    Internship Guide: Work Placements Step by Step has been written from the practical perspective of a placement coordinator. This book addresses the following questions : what problems do students encounter when they start thinking about the jobs their degree programme prepares them for? How do you

  10. The way to collisions, step by step

    CERN Multimedia

    2009-01-01

    While the LHC sectors cool down and reach the cryogenic operating temperature, spirits are warming up as we all eagerly await the first collisions. No reason to hurry, though. Making particles collide involves the complex manoeuvring of thousands of delicate components. The experts will make it happen using a step-by-step approach.

  11. A novel one-step real-time multiplex PCR assay to detect Streptococcus agalactiae presence and serotypes Ia, Ib, and III.

    Science.gov (United States)

    Furfaro, Lucy L; Chang, Barbara J; Payne, Matthew S

    2017-09-01

    Streptococcus agalactiae is the leading cause of early-onset neonatal sepsis. Culture-based screening methods lack the sensitivity of molecular assays and do not indicate serotype; a potentially important virulence marker. We aimed to develop a multiplex PCR to detect S. agalactiae while simultaneously identifying serotypes Ia, Ib, and III; commonly associated with infant disease. Primers were designed to target S. agalactiae serotype-specific cps genes and the dltS gene. The assay was validated with 512 vaginal specimens from pregnant women. 112 (21.9%) were dltS positive, with 14.3%, 0.9%, and 6.3% of these identified as cps Ia, Ib, and III, respectively. Our assay is a specific and sensitive method to simultaneously detect S. agalactiae and serotypes Ia, Ib, and III in a single step. It is of high significance for clinical diagnostic applications and also provides epidemiological data on serotype, information that may be important for vaccine development and other targeted non-antibiotic therapies. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Protein restriction and cancer.

    Science.gov (United States)

    Yin, Jie; Ren, Wenkai; Huang, Xingguo; Li, Tiejun; Yin, Yulong

    2018-03-26

    Protein restriction without malnutrition is currently an effective nutritional intervention known to prevent diseases and promote health span from yeast to human. Recently, low protein diets are reported to be associated with lowered cancer incidence and mortality risk of cancers in human. In murine models, protein restriction inhibits tumor growth via mTOR signaling pathway. IGF-1, amino acid metabolic programing, FGF21, and autophagy may also serve as potential mechanisms of protein restriction mediated cancer prevention. Together, dietary intervention aimed at reducing protein intake can be beneficial and has the potential to be widely adopted and effective in preventing and treating cancers. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Stability of one-step methods in transient nonlinear heat conduction

    International Nuclear Information System (INIS)

    Hughes, J.R.

    1977-01-01

    The purpose of the present work is to ascertain practical stability conditions for one-step methods commonly used in transient nonlinear heat conduction analyses. The class of problems considered is governed by a temporally continuous, spatially discrete system involving the capacity matrix C, conductivity matrix K, heat supply vector, temperature vector and time differenciation. In the linear case, in which K and C are constant, the stability behavior of one-step methods is well known. But in this paper the concepts of stability, appropriate to the nonlinear problem, are thoroughly discussed. They of course reduce to the usual stability criterion for the linear, constant coefficient case. However, for nonlinear problems there are differences and these ideas are of key importance in obtaining practical stability conditions. Of particular importance is a recent result which indicates that, in a sense, the trapezoidal and midpoint families are quivalent. Thus, stability results for one family may be translated into a result for the other. The main results obtained are summarized as follows. The stability behavior of the explicit Euler method in the nonlinear regime is analogous to that for linear problems. In particular, an a priori step size restriction may be determined for each time step. The precise time step restriction on implicit conditionally stable members of the trapezoidal and midpoint families is shown not to be determinable a priori. Of considerable practical significance, unconditionally stable members of the trapezoidal and midpoint families are identified

  14. Initial evaluation of prostate cancer with real-time elastography based on step-section pathologic analysis after radical prostatectomy. A preliminary study

    International Nuclear Information System (INIS)

    Sumura, Masahiro; Shigeno, Kazushi; Hyuga, Taiju; Yoneda, Tatsuaki; Shiina, Hiroaki; Igawa, Mikio

    2007-01-01

    The objective of this study was to determine whether real-time elastography can be used to detect prostate cancer as a relatively non-invasive modality based on the tissue strain value. Seventeen patients underwent real-time elastography in conjunction with digital rectal examination (DRE), conventional gray-scale transrectal ultrasonography (TRUS), color Doppler ultrasonography (CDUS), and magnetic resonance imaging (MRI) prior to radical prostatectomy. The elastogram was compared to findings of conventional modalities and pathological findings of prostatectomy specimens. To obtain the elastogram, compression of the prostate was performed along with a visual indicator on a video screen. Twenty of 27 pathologically confirmed tumors were detected with real-time elastography. The cancer detection rate with real-time elastography was superior to the rates of other modalities and nearly equal to both on the anterior side (75.0%) and the posterior side (73.7%) of the prostate. A higher tumor detection rate for real-time elastography was observed for tumors with a higher Gleason score and larger tumor volume. In our preliminary study, real-time elastography in conjunction with gray-scale TRUS is a non-invasive modality to detect prostate cancer. (author)

  15. Node Immunization with Time-Sensitive Restrictions

    Directory of Open Access Journals (Sweden)

    Wen Cui

    2016-12-01

    Full Text Available When we encounter a malicious rumor or an infectious disease outbreak, immunizing k nodes of the relevant network with limited resources is always treated as an extremely effective method. The key challenge is how we can insulate limited nodes to minimize the propagation of those contagious things. In previous works, the best k immunised nodes are selected by learning the initial status of nodes and their strategies even if there is no feedback in the propagation process, which eventually leads to ineffective performance of their solutions. In this paper, we design a novel vaccines placement strategy for protecting much more healthy nodes from being infected by infectious nodes. The main idea of our solution is that we are not only utilizing the status of changing nodes as auxiliary knowledge to adjust our scheme, but also comparing the performance of vaccines in various transmission slots. Thus, our solution has a better chance to get more benefit from these limited vaccines. Extensive experiments have been conducted on several real-world data sets and the results have shown that our algorithm has a better performance than previous works.

  16. Intrauterine growth restriction

    Directory of Open Access Journals (Sweden)

    Bernardita Donoso Bernales

    2012-07-01

    Full Text Available It is estimated that the true prevalence of intrauterine growth restriction is 3-10% of all pregnancies, making this fetal condition one of the most frequent obstetric problems, together with premature labor and premature rupture of membranes. The article stresses the importance of early diagnosis because of the associated risks.

  17. Late gestational nutrient restriction

    DEFF Research Database (Denmark)

    Tygesen, Malin Plumhoff; Nielsen, Mette Olaf; Nørgaard, Peder

    2008-01-01

    We investigated the effect of 50% nutrient restriction during the last 6 weeks of gestation on twin-pregnant ewes' plasma glucose, non-esterified fatty acid, ß-hydroxybutyrate, insulin, IGF-1 and leptin concentrations and the effects on lamb birth weight and ewes' lactation performance. Plasma...

  18. Restricted Variance Interaction Effects

    DEFF Research Database (Denmark)

    Cortina, Jose M.; Köhler, Tine; Keeler, Kathleen R.

    2018-01-01

    Although interaction hypotheses are increasingly common in our field, many recent articles point out that authors often have difficulty justifying them. The purpose of this article is to describe a particular type of interaction: the restricted variance (RV) interaction. The essence of the RV int...

  19. 20 CFR 655.1114 - Element IV-What are the timely and significant steps an H-1C employer must take to recruit and...

    Science.gov (United States)

    2010-04-01

    ... that constitute a “significant” factor in inducing employment and retention of U.S. nurses. (iii) Work schedule options. The facility provides nurses with non-mandatory work schedule options for part-time work, job-sharing, compressed work week or non-rotating shifts (provided, however, that H-1C nurses are...

  20. Factors Associated with Objectively Measured Physical Activity and Sedentary Time of 5-6-Year-Old Children in the STEPS Study

    Science.gov (United States)

    Matarma, Tanja; Tammelin, Tuija; Kulmala, Janne; Koski, Pasi; Hurme, Saija; Lagström, Hanna

    2017-01-01

    Background: The factors associated with preschool-aged children's physical activity (PA) remains unclear. The aim of this cross-sectional study was to examine how different factors were associated with preschool-aged children's objectively measured PA and sedentary time. Methods: The study population was 5-6-year-old children (n = 140) and their…

  1. Behavioural repertoire of working donkeys and consistency of behaviour over time, as a preliminary step towards identifying pain-related behaviours.

    Science.gov (United States)

    Regan, Fran H; Hockenhull, Jo; Pritchard, Joy C; Waterman-Pearson, Avril E; Whay, Helen R

    2014-01-01

    The donkey has a reputation for stoicism and its behavioural repertoire in clinical contexts is under-reported. Lack of understanding of the norms of donkey behaviour and how it may vary over time can compromise use of behavioural measures as indicators of pain or emotional state. The objective of this study was to find out whether the behaviour of working donkeys was influenced by gender, the time of day or differed between days with a view to assessing how robust these measures are for inclusion in a working donkey ethogram. Frequency and consistency of postural and event behaviours were measured in 21 adult working donkeys (12 females; 9 males). Instantaneous (scan) and focal sampling were used to measure maintenance, lying, ingestive and investigative behaviours at hourly intervals for ten sessions on each of two consecutive days. High head carriage and biting were seen more frequently in male donkeys than females (Pdonkeys (Pdonkeys expressed an extensive behavioural repertoire, although some differences in behaviour were evident between genders. While most behaviours were consistent over time, some behaviours were influenced by time of day. Few behaviours differed between the two test days. The findings can be used to inform the development of a robust, evidence-based ethogram for working donkeys.

  2. Behavioural repertoire of working donkeys and consistency of behaviour over time, as a preliminary step towards identifying pain-related behaviours.

    Directory of Open Access Journals (Sweden)

    Fran H Regan

    Full Text Available The donkey has a reputation for stoicism and its behavioural repertoire in clinical contexts is under-reported. Lack of understanding of the norms of donkey behaviour and how it may vary over time can compromise use of behavioural measures as indicators of pain or emotional state. The objective of this study was to find out whether the behaviour of working donkeys was influenced by gender, the time of day or differed between days with a view to assessing how robust these measures are for inclusion in a working donkey ethogram.Frequency and consistency of postural and event behaviours were measured in 21 adult working donkeys (12 females; 9 males. Instantaneous (scan and focal sampling were used to measure maintenance, lying, ingestive and investigative behaviours at hourly intervals for ten sessions on each of two consecutive days. High head carriage and biting were seen more frequently in male donkeys than females (P<0.001. Level head carriage, licking/chewing and head-shaking were observed more frequently in female donkeys (P<0.001. Tail position, ear orientation, foot stamping, rolling/lying and head-shaking behaviours were affected by time of day (P<0.001. However, only two variations in ear orientation were found to be significantly different over the two days of observations (P<0.001. Tail swishing, head shaking, foot stamping, and ears held sideways and downwards were significantly correlated (P<0.001 and are assumed to be behaviours to discourage flies.All donkeys expressed an extensive behavioural repertoire, although some differences in behaviour were evident between genders. While most behaviours were consistent over time, some behaviours were influenced by time of day. Few behaviours differed between the two test days. The findings can be used to inform the development of a robust, evidence-based ethogram for working donkeys.

  3. Public Investment, Revenue Shocks, and Borrowing Restrictions

    OpenAIRE

    Büttner, Thiess; Wildasin, David E.

    2010-01-01

    This paper lays out a theory of taxation and public investment in an intertemporal setting under conditions of revenue shocks. Without borrowing restrictions, the optimal policy is characterized by smooth time paths of taxes and public investment. While the introduction of formal borrowing restrictions leads to some precautionary savings, it gives rise to fluctuations in public investment in response to adverse but also favorable revenue shocks. This theoretical result is tested empirically u...

  4. Enterocytozoon bieneusi Identification Using Real-Time Polymerase Chain Reaction and Restriction Fragment Length Polymorphism in HIV-Infected Humans from Kinshasa Province of the Democratic Republic of Congo

    Science.gov (United States)

    Wumba, Roger; Jean, Menotti; Benjamin, Longo-Mbenza; Madone, Mandina; Fabien, Kintoki; Josué, Zanga; Jean, Sala; Eric, Kendjo; AC, Guillo-Olczyk; Marc, Thellier

    2012-01-01

    Objective. To determine the prevalence and the genotypes of Enterocytozoon bieneusi in stool specimens from HIV patients. Methods. This cross-sectional study was carried out in Kinshasa hospitals between 2009 and 2012. Detection of microsporidia including E. bieneusi and E. intestinalis was performed in 242 HIV-infected patients. Typing was based on DNA polymorphism of the ribosomal DNA ITS region of E. bieneusi. PCRRFLP generated with two restriction enzymes (Nla III and Fnu 4HI) in PCR-amplified ITS products for classifying strains into different lineages. The diagnosis performance of the indirect immune-fluorescence-monoclonal antibody (IFI-AcM) was defined in comparison with real-time PCR as the gold standard. Results. Out of 242 HIV-infected patients, using the real-time PCR, the prevalence of E. bieneusi was 7.9% (n = 19) among the 19 E. bieneusi, one was coinfected with E. intestinalis. In 19 E. bieneusi persons using PCR-RFLP method, 5 type I strains of E. bieneusi (26.3%) and 5 type IV strains of E. bieneusi (26.3%) were identified. The sensitivity of IFI-AcM was poor as estimated 42.1%. Conclusion. Despite different PCR methods, there is possible association between HIVinfection, geographic location (France, Cameroun, Democratic Republic of Congo), and the concurrence of type I and type IV strains. PMID:22811884

  5. A Step Toward Timely Referral and Early Diagnosis of Cancer: Implementation and Impact on Knowledge of a Primary Care-Based Training Program in Botswana

    Directory of Open Access Journals (Sweden)

    Neo M. Tapela

    2018-05-01

    Full Text Available IntroductionHealth system delays in diagnosis of cancer contribute to the glaring disparities in cancer mortality between high-income countries and low- and middle-income countries. In Botswana, approximately 70% of cancers are diagnosed at late stage and median time from first health facility visit for cancer-related symptoms to specialty cancer care was 160 days (IQR 59–653. We describe the implementation and early outcomes of training targeting primary care providers, which is a part of a multi-component implementation study in Kweneng-East district aiming to enhance timely diagnosis of cancers.MethodsHealth-care providers from all public facilities within the district were invited to participate in an 8-h intensive short-course program developed by a multidisciplinary team and adapted to the Botswana health system context. Participants’ performance was assessed using a 25-multiple choice question tool, with pre- and post-assessments paired by anonymous identifier. Statistical analysis with Wilcoxon signed-rank test to compare performance at the two time points across eight sub-domains (pathophysiology, epidemiology, social context, symptoms, evaluation, treatment, documentation, follow-up. Linear regression and negative binomial modeling were used to determine change in performance. Participants’ satisfaction with the program was measured on a separate survey using a 5-point Likert scale.Results176 participants attended the training over 5 days in April 2016. Pooled linear regression controlling for test version showed an overall performance increase of 16.8% after participation (95% CI 15.2–18.4. Statistically significant improvement was observed for seven out of eight subdomains on test A and all eight subdomains on test B. Overall, 71 (40.3% trainees achieved a score greater than 70% on the pretest, and 161 (91.5% did so on the posttest. Participants reported a high degree of satisfaction with the training program’s content

  6. SYBR green-based one step quantitative real-time polymerase chain reaction assay for the detection of Zika virus in field-caught mosquitoes.

    Science.gov (United States)

    Tien, Wei-Ping; Lim, Gareth; Yeo, Gladys; Chiang, Suzanna Nicole; Chong, Chee-Seng; Ng, Lee-Ching; Hapuarachchi, Hapuarachchige Chanditha

    2017-09-19

    The monitoring of vectors is one of the key surveillance measures to assess the risk of arbovirus transmission and the success of control strategies in endemic regions. The recent re-emergence of Zika virus (ZIKV) in the tropics, including Singapore, emphasizes the need to develop cost-effective, rapid and accurate assays to monitor the virus spread by mosquitoes. As ZIKV infections largely remain asymptomatic, early detection of ZIKV in the field-caught mosquitoes enables timely implementation of appropriate mosquito control measures. We developed a rapid, sensitive and specific real-time reverse transcription polymerase chain reaction (rRT-PCR) assay for the detection of ZIKV in field-caught mosquitoes. The primers and PCR cycling conditions were optimized to minimize non-specific amplification due to cross-reactivity with the genomic material of Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, Culex tritaeniorhynchus, Culex sitiens and Anopheles sinensis, as well as accompanying microbiota. The performance of the assay was further evaluated with a panel of flaviviruses and alphaviruses as well as in field-caught Ae. aegypti mosquitoes confirmed to be positive for ZIKV. As compared to a probe-based assay, the newly developed assay demonstrated 100% specificity and comparable detection sensitivity for ZIKV in mosquitoes. Being a SYBR Green-based method, the newly-developed assay is cost-effective and easy to adapt, thus is applicable to large-scale vector surveillance activities in endemic countries, including those with limited resources and expertise. The amplicon size (119 bp) also allows sequencing to confirm the virus type. The primers flank relatively conserved regions of ZIKV genome, so that, the assay is able to detect genetically diverse ZIKV strains. Our findings, therefore, testify the potential use of the newly-developed assay in vector surveillance programmes for ZIKV in endemic regions.

  7. Comparison of Stepped Care Delivery Against a Single, Empirically Validated Cognitive-Behavioral Therapy Program for Youth With Anxiety: A Randomized Clinical Trial.

    Science.gov (United States)

    Rapee, Ronald M; Lyneham, Heidi J; Wuthrich, Viviana; Chatterton, Mary Lou; Hudson, Jennifer L; Kangas, Maria; Mihalopoulos, Cathrine

    2017-10-01

    Stepped care is embraced as an ideal model of service delivery but is minimally evaluated. The aim of this study was to evaluate the efficacy of cognitive-behavioral therapy (CBT) for child anxiety delivered via a stepped-care framework compared against a single, empirically validated program. A total of 281 youth with anxiety disorders (6-17 years of age) were randomly allocated to receive either empirically validated treatment or stepped care involving the following: (1) low intensity; (2) standard CBT; and (3) individually tailored treatment. Therapist qualifications increased at each step. Interventions did not differ significantly on any outcome measures. Total therapist time per child was significantly shorter to deliver stepped care (774 minutes) compared with best practice (897 minutes). Within stepped care, the first 2 steps returned the strongest treatment gains. Stepped care and a single empirically validated program for youth with anxiety produced similar efficacy, but stepped care required slightly less therapist time. Restricting stepped care to only steps 1 and 2 would have led to considerable time saving with modest loss in efficacy. Clinical trial registration information-A Randomised Controlled Trial of Standard Care Versus Stepped Care for Children and Adolescents With Anxiety Disorders; http://anzctr.org.au/; ACTRN12612000351819. Copyright © 2017 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

  8. Urban water restrictions: Attitudes and avoidance

    Science.gov (United States)

    Cooper, Bethany; Burton, Michael; Crase, Lin

    2011-12-01

    In most urban cities across Australia, water restrictions remain the dominant policy mechanism to restrict urban water consumption. The extensive adoption of water restrictions as a means to limit demand, over several years, means that Australian urban water prices have consistently not reflected the opportunity cost of water. Given the generally strong political support for water restrictions and the likelihood that they will persist for some time, there is value in understanding households' attitudes in this context. More specifically, identifying the welfare gains associated with avoiding urban water restrictions entirely would be a nontrivial contribution to our knowledge and offer insights into the benefits of alternative policy responses. This paper describes the results from a contingent valuation study that investigates consumers' willingness to pay to avoid urban water restrictions. Importantly, the research also investigates the influence of cognitive and exogenous dimensions on the utility gain associated with avoiding water restrictions. The results provide insights into the impact of the current policy mechanism on economic welfare.

  9. Step by Step Microsoft Office Visio 2003

    CERN Document Server

    Lemke, Judy

    2004-01-01

    Experience learning made easy-and quickly teach yourself how to use Visio 2003, the Microsoft Office business and technical diagramming program. With STEP BY STEP, you can take just the lessons you need, or work from cover to cover. Either way, you drive the instruction-building and practicing the skills you need, just when you need them! Produce computer network diagrams, organization charts, floor plans, and moreUse templates to create new diagrams and drawings quicklyAdd text, color, and 1-D and 2-D shapesInsert graphics and pictures, such as company logosConnect shapes to create a basic f

  10. Step Sizes for Strong Stability Preservation with Downwind-Biased Operators

    KAUST Repository

    Ketcheson, David I.

    2011-01-01

    order accuracy. It is possible to achieve more relaxed step size restrictions in the discretization of hyperbolic PDEs through the use of both upwind- and downwind-biased semidiscretizations. We investigate bounds on the maximum SSP step size for methods

  11. Preimages for Step-Reduced SHA-2

    DEFF Research Database (Denmark)

    Aoki, Kazumaro; Guo, Jian; Matusiewicz, Krystian

    2009-01-01

    In this paper, we present preimage attacks on up to 43-step SHA-256 (around 67% of the total 64 steps) and 46-step SHA-512 (around 57.5% of the total 80 steps), which significantly increases the number of attacked steps compared to the best previously published preimage attack working for 24 steps....... The time complexities are 2^251.9, 2^509 for finding pseudo-preimages and 2^254.9, 2^511.5 compression function operations for full preimages. The memory requirements are modest, around 2^6 words for 43-step SHA-256 and 46-step SHA-512. The pseudo-preimage attack also applies to 43-step SHA-224 and SHA-384...

  12. Research on test of product based on spatial sampling criteria and variable step sampling mechanism

    Science.gov (United States)

    Li, Ruihong; Han, Yueping

    2014-09-01

    This paper presents an effective approach for online testing the assembly structures inside products using multiple views technique and X-ray digital radiography system based on spatial sampling criteria and variable step sampling mechanism. Although there are some objects inside one product to be tested, there must be a maximal rotary step for an object within which the least structural size to be tested is predictable. In offline learning process, Rotating the object by the step and imaging it and so on until a complete cycle is completed, an image sequence is obtained that includes the full structural information for recognition. The maximal rotary step is restricted by the least structural size and the inherent resolution of the imaging system. During online inspection process, the program firstly finds the optimum solutions to all different target parts in the standard sequence, i.e., finds their exact angles in one cycle. Aiming at the issue of most sizes of other targets in product are larger than that of the least structure, the paper adopts variable step-size sampling mechanism to rotate the product specific angles with different steps according to different objects inside the product and match. Experimental results show that the variable step-size method can greatly save time compared with the traditional fixed-step inspection method while the recognition accuracy is guaranteed.

  13. Free Modal Algebras Revisited: The Step-by-Step Method

    NARCIS (Netherlands)

    Bezhanishvili, N.; Ghilardi, Silvio; Jibladze, Mamuka

    2012-01-01

    We review the step-by-step method of constructing finitely generated free modal algebras. First we discuss the global step-by-step method, which works well for rank one modal logics. Next we refine the global step-by-step method to obtain the local step-by-step method, which is applicable beyond

  14. Implicit time accurate simulation of unsteady flow

    Science.gov (United States)

    van Buuren, René; Kuerten, Hans; Geurts, Bernard J.

    2001-03-01

    Implicit time integration was studied in the context of unsteady shock-boundary layer interaction flow. With an explicit second-order Runge-Kutta scheme, a reference solution to compare with the implicit second-order Crank-Nicolson scheme was determined. The time step in the explicit scheme is restricted by both temporal accuracy as well as stability requirements, whereas in the A-stable implicit scheme, the time step has to obey temporal resolution requirements and numerical convergence conditions. The non-linear discrete equations for each time step are solved iteratively by adding a pseudo-time derivative. The quasi-Newton approach is adopted and the linear systems that arise are approximately solved with a symmetric block Gauss-Seidel solver. As a guiding principle for properly setting numerical time integration parameters that yield an efficient time accurate capturing of the solution, the global error caused by the temporal integration is compared with the error resulting from the spatial discretization. Focus is on the sensitivity of properties of the solution in relation to the time step. Numerical simulations show that the time step needed for acceptable accuracy can be considerably larger than the explicit stability time step; typical ratios range from 20 to 80. At large time steps, convergence problems that are closely related to a highly complex structure of the basins of attraction of the iterative method may occur. Copyright

  15. Diabetes PSA (:30) Step By Step

    Centers for Disease Control (CDC) Podcasts

    2009-10-24

    First steps to preventing diabetes. For Hispanic and Latino American audiences.  Created: 10/24/2009 by National Diabetes Education Program (NDEP), a joint program of the Centers for Disease Control and Prevention and the National Institutes of Health.   Date Released: 10/24/2009.

  16. Diabetes PSA (:60) Step By Step

    Centers for Disease Control (CDC) Podcasts

    2009-10-24

    First steps to preventing diabetes. For Hispanic and Latino American audiences.  Created: 10/24/2009 by National Diabetes Education Program (NDEP), a joint program of the Centers for Disease Control and Prevention and the National Institutes of Health.   Date Released: 10/24/2009.

  17. Comment on 'Shang S. 2012. Calculating actual crop evapotranspiration under soil water stress conditions with appropriate numerical methods and time step. Hydrological Processes 26: 3338-3343. DOI: 10.1002/hyp.8405'

    Science.gov (United States)

    Yatheendradas, Soni; Narapusetty, Balachandrudu; Peters-Lidard, Christa; Funk, Christopher; Verdin, James

    2014-01-01

    A previous study analyzed errors in the numerical calculation of actual crop evapotranspiration (ET(sub a)) under soil water stress. Assuming no irrigation or precipitation, it constructed equations for ET(sub a) over limited soil-water ranges in a root zone drying out due to evapotranspiration. It then used a single crop-soil composite to provide recommendations about the appropriate usage of numerical methods under different values of the time step and the maximum crop evapotranspiration (ET(sub c)). This comment reformulates those ET(sub a) equations for applicability over the full range of soil water values, revealing a dependence of the relative error in numerical ET(sub a) on the initial soil water that was not seen in the previous study. It is shown that the recommendations based on a single crop-soil composite can be invalid for other crop-soil composites. Finally, a consideration of the numerical error in the time-cumulative value of ET(sub a) is discussed besides the existing consideration of that error over individual time steps as done in the previous study. This cumulative ET(sub a) is more relevant to the final crop yield.

  18. Microsoft Office Word 2007 step by step

    CERN Document Server

    Cox, Joyce

    2007-01-01

    Experience learning made easy-and quickly teach yourself how to create impressive documents with Word 2007. With Step By Step, you set the pace-building and practicing the skills you need, just when you need them!Apply styles and themes to your document for a polished lookAdd graphics and text effects-and see a live previewOrganize information with new SmartArt diagrams and chartsInsert references, footnotes, indexes, a table of contentsSend documents for review and manage revisionsTurn your ideas into blogs, Web pages, and moreYour all-in-one learning experience includes:Files for building sk

  19. Microsoft Office SharePoint Designer 2007 Step by Step

    CERN Document Server

    Coventry, Penelope

    2008-01-01

    The smart way to learn Office SharePoint Designer 2007-one step at a time! Work at your own pace through the easy numbered steps, practice files on CD, helpful hints, and troubleshooting tips to master the fundamentals of building customized SharePoint sites and applications. You'll learn how to work with Windows® SharePoint Services 3.0 and Office SharePoint Server 2007 to create Web pages complete with Cascading Style Sheets, Lists, Libraries, and customized Web parts. Then, make your site really work for you by adding data sources, including databases, XML data and Web services, and RSS fe

  20. Stepping out: dare to step forward, step back, or just stand still and breathe.

    Science.gov (United States)

    Waisman, Mary Sue

    2012-01-01

    It is important to step out and make a difference. We have one of the most unique and diverse professions that allows for diversity in thought and practice, permitting each of us to grow in our unique niches and make significant contributions. I was frightened to 'step out' to go to culinary school at the age of 46, but it changed forever the way I look at my profession and I have since experienced the most enjoyable and innovative career. There are also times when it is important to 'step back' to relish the roots of our profession; to help bring food back into nutrition; to translate all of our wonderful science into a language of food that Canadians understand. We all need to take time to 'just stand still and breathe': to celebrate our accomplishments, reflect on our actions, ensure we are heading toward our vision, keep the profession vibrant and relevant, and cherish one another.

  1. Stability of one-step methods in transient nonlinear heat conduction

    International Nuclear Information System (INIS)

    Hughes, J.R.

    1977-01-01

    The purpose of the present work is to ascertain practical stability conditions for one-step methods commonly used in transient nonlinear heat conduction analyses. In this paper the concepts of stability, appropriate to the nonlinear problem, are thoroughly discussed. They of course reduce to the usual stability critierion for the linear, constant coefficient case. However, for nonlinear problems there are differences and theses ideas are of key importance in obtaining practical stability conditions. Of particular importance is a recent result which indicates that, in a sense, the trapezoidal and midpoint families are equivalent. Thus, stability results for one family may be translated into a result for the other. The main results obtained are: The stability behaviour of the explicit Euler method in the nonlinear regime is analogous to that for linear problems. In particular, an a priori step size restriction may be determined for each time step. The precise time step restriction on implicit conditionally stable members of the trapezoidal and midpoint families is shown not to be determinable a priori. Of considerable practical significance, unconditionally stable members of the trapezoidal and midpoint families are identified. All notions of stability employed are motivated and defined, and their interpretations in practical computing are indicated. (Auth.)

  2. Stepping Stones and Creating Futures intervention: shortened interrupted time series evaluation of a behavioural and structural health promotion and violence prevention intervention for young people in informal settlements in Durban, South Africa.

    Science.gov (United States)

    Jewkes, Rachel; Gibbs, Andrew; Jama-Shai, Nwabisa; Willan, Samantha; Misselhorn, Alison; Mushinga, Mildred; Washington, Laura; Mbatha, Nompumelelo; Skiweyiya, Yandisa

    2014-12-29

    Gender-based violence and HIV are highly prevalent in the harsh environment of informal settlements and reducing violence here is very challenging. The group intervention Stepping Stones has been shown to reduce men's perpetration of violence in more rural areas, but violence experienced by women in the study was not affected. Economic empowerment interventions with gender training can protect older women from violence, but microloan interventions have proved challenging with young women. We investigated whether combining a broad economic empowerment intervention and Stepping Stones could impact on violence among young men and women. The intervention, Creating Futures, was developed as a new generation of economic empowerment intervention, which enabled livelihood strengthening though helping participants find work or set up a business, and did not give cash or make loans. We piloted Stepping Stones with Creating Futures in two informal settlements of Durban with 232 out of school youth, mostly aged 18-30 and evaluated with a shortened interrupted time series of two baseline surveys and at 28 and 58 weeks post-baseline. 94/110 men and 111/122 women completed the last assessment, 85.5% and 90.2% respectively of those enrolled. To determine trend, we built random effects regression models with each individual as the cluster for each variable, and measured the slope of the line across the time points. Men's mean earnings in the past month increased by 247% from R411 (~$40) to R1015 (~$102, and women's by 278% R 174 (~$17) to R 484 (about $48) (trend test, p < 0.0001). There was a significant reduction in women's experience of the combined measure of physical and/or sexual IPV in the prior three months from 30.3% to 18.9% (p = 0.037). This was not seen for men. However both men and women scored significantly better on gender attitudes and men significantly reduced their controlling practices in their relationship. The prevalence of moderate or severe depression

  3. Company Law as a Restriction to Free Movement

    DEFF Research Database (Denmark)

    Sørensen, Karsten Engsig

    2014-01-01

    . There is evidence that non-discriminatory obstacles to free movement found in company law can be restrictions. However, recent cases show that the Court may be willing to apply a more restrictive approach where only non-discriminatory measures that have a qualified deterrent effect may constitute restrictions.......Focusing on recent judgments from the Court of Justice of the European Union, this article investigates how the notion of ‘restriction’ – which is the first step in examining whether there is an infringement of the free movement rights – is used in cases involving company law measures...

  4. Training Restricted Boltzmann Machines

    DEFF Research Database (Denmark)

    Fischer, Asja

    relies on sampling based approximations of the log-likelihood gradient. I will present an empirical and theoretical analysis of the bias of these approximations and show that the approximation error can lead to a distortion of the learning process. The bias decreases with increasing mixing rate......Restricted Boltzmann machines (RBMs) are probabilistic graphical models that can also be interpreted as stochastic neural networks. Training RBMs is known to be challenging. Computing the likelihood of the model parameters or its gradient is in general computationally intensive. Thus, training...... of the applied sampling procedure and I will introduce a transition operator that leads to faster mixing. Finally, a different parametrisation of RBMs will be discussed that leads to better learning results and more robustness against changes in the data representation....

  5. Optimizing Restriction Site Placement for Synthetic Genomes

    Science.gov (United States)

    Montes, Pablo; Memelli, Heraldo; Ward, Charles; Kim, Joondong; Mitchell, Joseph S. B.; Skiena, Steven

    Restriction enzymes are the workhorses of molecular biology. We introduce a new problem that arises in the course of our project to design virus variants to serve as potential vaccines: we wish to modify virus-length genomes to introduce large numbers of unique restriction enzyme recognition sites while preserving wild-type function by substitution of synonymous codons. We show that the resulting problem is NP-Complete, give an exponential-time algorithm, and propose effective heuristics, which we show give excellent results for five sample viral genomes. Our resulting modified genomes have several times more unique restriction sites and reduce the maximum gap between adjacent sites by three to nine-fold.

  6. Step by step parallel programming method for molecular dynamics code

    International Nuclear Information System (INIS)

    Orii, Shigeo; Ohta, Toshio

    1996-07-01

    Parallel programming for a numerical simulation program of molecular dynamics is carried out with a step-by-step programming technique using the two phase method. As a result, within the range of a certain computing parameters, it is found to obtain parallel performance by using the level of parallel programming which decomposes the calculation according to indices of do-loops into each processor on the vector parallel computer VPP500 and the scalar parallel computer Paragon. It is also found that VPP500 shows parallel performance in wider range computing parameters. The reason is that the time cost of the program parts, which can not be reduced by the do-loop level of the parallel programming, can be reduced to the negligible level by the vectorization. After that, the time consuming parts of the program are concentrated on less parts that can be accelerated by the do-loop level of the parallel programming. This report shows the step-by-step parallel programming method and the parallel performance of the molecular dynamics code on VPP500 and Paragon. (author)

  7. Extended Follow-up Confirms Early Vaccine-Enhanced Risk of HIV Acquisition and Demonstrates Waning Effect Over Time Among Participants in a Randomized Trial of Recombinant Adenovirus HIV Vaccine (Step Study)

    Science.gov (United States)

    Duerr, Ann; Huang, Yunda; Buchbinder, Susan; Coombs, Robert W.; Sanchez, Jorge; del Rio, Carlos; Casapia, Martin; Santiago, Steven; Gilbert, Peter; Corey, Lawrence; Robertson, Michael N.

    2012-01-01

    Background. The Step Study tested whether an adenovirus serotype 5 (Ad5)–vectored human immunodeficiency virus (HIV) vaccine could prevent HIV acquisition and/or reduce viral load set-point after infection. At the first interim analysis, nonefficacy criteria were met. Vaccinations were halted; participants were unblinded. In post hoc analyses, more HIV infections occurred in vaccinees vs placebo recipients in men who had Ad5-neutralizing antibodies and/or were uncircumcised. Follow-up was extended to assess relative risk of HIV acquisition in vaccinees vs placebo recipients over time. Methods. We used Cox proportional hazard models for analyses of vaccine effect on HIV acquisition and vaccine effect modifiers, and nonparametric and semiparametric methods for analysis of constancy of relative risk over time. Results. One hundred seventy-two of 1836 men were infected. The adjusted vaccinees vs placebo recipients hazard ratio (HR) for all follow-up time was 1.40 (95% confidence interval [CI], 1.03–1.92; P = .03). Vaccine effect differed by baseline Ad5 or circumcision status during first 18 months, but neither was significant for all follow-up time. The HR among uncircumcised and/or Ad5-seropositive men waned with time since vaccination. No significant vaccine-associated risk was seen among circumcised, Ad5-negative men (HR, 0.97; P = 1.0) over all follow-up time. Conclusions. The vaccine-associated risk seen in interim analysis was confirmed but waned with time from vaccination. Clinical Trials Registration. NCT00095576. PMID:22561365

  8. From atoms to steps: The microscopic origins of crystal evolution

    Science.gov (United States)

    Patrone, Paul N.; Einstein, T. L.; Margetis, Dionisios

    2014-07-01

    The Burton-Cabrera-Frank (BCF) theory of crystal growth has been successful in describing a wide range of phenomena in surface physics. Typical crystal surfaces are slightly misoriented with respect to a facet plane; thus, the BCF theory views such systems as composed of staircase-like structures of steps separating terraces. Adsorbed atoms (adatoms), which are represented by a continuous density, diffuse on terraces, and steps move by absorbing or emitting these adatoms. Here we shed light on the microscopic origins of the BCF theory by deriving a simple, one-dimensional (1D) version of the theory from an atomistic, kinetic restricted solid-on-solid (KRSOS) model without external material deposition. We define the time-dependent adatom density and step position as appropriate ensemble averages in the KRSOS model, thereby exposing the non-equilibrium statistical mechanics origins of the BCF theory. Our analysis reveals that the BCF theory is valid in a low adatom-density regime, much in the same way that an ideal gas approximation applies to dilute gasses. We find conditions under which the surface remains in a low-density regime and discuss the microscopic origin of corrections to the BCF model.

  9. Comparison of the genexpert enterovirus assay (GXEA) with real-time one step RT-PCR for the detection of enteroviral RNA in the cerebrospinal fluid of patients with meningitis.

    Science.gov (United States)

    Hong, JiYoung; Kim, Ahyoun; Hwang, Seoyeon; Cheon, Doo-Sung; Kim, Jong-Hyen; Lee, June-Woo; Park, Jae-Hak; Kang, Byunghak

    2015-02-13

    Enteroviruses (EVs) are the leading cause of aseptic meningitis worldwide. Detection of enteroviral RNA in clinical specimens has been demonstrated to improve the management of patient care, especially that of neonates and young children. To establish a sensitive and reliable assay for routine laboratory diagnosis, we compared the sensitivity and specificity of the GeneXpert Enterovirus Assay (GXEA) with that of the reverse transcription polymerase chain reaction (RT-PCR) based assay referred to as real-time one step RT-PCR (RTo-PCR). The sensitivity/specificity produced by GXEA and RTo-PCR were 100%/100% and 65%/100%, respectively. Both methods evaluated in this article can be used for detection of enterovirus in clinical specimens and these nucleic acid amplification methods are useful assays for the diagnosis of enteroviral infection.

  10. A one-step, triplex, real-time RT-PCR assay for the simultaneous detection of enterovirus 71, coxsackie A16 and pan-enterovirus in a single tube.

    Directory of Open Access Journals (Sweden)

    Shiyin Zhang

    Full Text Available The recent, ongoing epidemic of hand, foot, and mouth disease (HFMD, which is caused by enterovirus infection, has affected millions of children and resulted in thousands of deaths in China. Enterovirus 71 (EV71 and coxsackie A16 (CA16 are the two major distinct pathogens for HFMD. However, EV71 is more commonly associated with neurologic complications and even fatalities. Therefore, simultaneously detecting and differentiating EV71 and CA16 specifically from other enteroviruses for diagnosing HFMD is important. Here, we developed a one-step, triplex, real-time RT-PCR assay for the simultaneous detection of EV71, CA16, and pan-enterovirus (EVs in a single tube with an internal amplification control. The detection results for the serially diluted viruses indicate that the lower limit of detection for this assay is 0.001-0.04 TCID50/ml, 0.02 TCID50/ml, and 0.001 TCID50/ml for EVs, EV71, and CA16, respectively. After evaluating known HFMD virus stocks of 17 strains of 16 different serotypes, this assay showed a favorable detection spectrum and no obvious cross-reactivity. The results for 141 clinical throat swabs from HFMD-suspected patients demonstrated sensitivities of 98.4%, 98.7%, and 100% for EVs, EV71, and CA16, respectively, and 100% specificity for each virus. The application of this one-step, triplex, real-time RT-PCR assay in clinical units will contribute to HFMD surveillance and help to identify causative pathogen in patients with suspected HFMD.

  11. A one-step, triplex, real-time RT-PCR assay for the simultaneous detection of enterovirus 71, coxsackie A16 and pan-enterovirus in a single tube.

    Science.gov (United States)

    Zhang, Shiyin; Wang, Jin; Yan, Qiang; He, Shuizhen; Zhou, Wenbin; Ge, Shengxiang; Xia, Ningshao

    2014-01-01

    The recent, ongoing epidemic of hand, foot, and mouth disease (HFMD), which is caused by enterovirus infection, has affected millions of children and resulted in thousands of deaths in China. Enterovirus 71 (EV71) and coxsackie A16 (CA16) are the two major distinct pathogens for HFMD. However, EV71 is more commonly associated with neurologic complications and even fatalities. Therefore, simultaneously detecting and differentiating EV71 and CA16 specifically from other enteroviruses for diagnosing HFMD is important. Here, we developed a one-step, triplex, real-time RT-PCR assay for the simultaneous detection of EV71, CA16, and pan-enterovirus (EVs) in a single tube with an internal amplification control. The detection results for the serially diluted viruses indicate that the lower limit of detection for this assay is 0.001-0.04 TCID50/ml, 0.02 TCID50/ml, and 0.001 TCID50/ml for EVs, EV71, and CA16, respectively. After evaluating known HFMD virus stocks of 17 strains of 16 different serotypes, this assay showed a favorable detection spectrum and no obvious cross-reactivity. The results for 141 clinical throat swabs from HFMD-suspected patients demonstrated sensitivities of 98.4%, 98.7%, and 100% for EVs, EV71, and CA16, respectively, and 100% specificity for each virus. The application of this one-step, triplex, real-time RT-PCR assay in clinical units will contribute to HFMD surveillance and help to identify causative pathogen in patients with suspected HFMD.

  12. Property Rights, Restrictions and Responsibilities

    DEFF Research Database (Denmark)

    Enemark, Stig

    more to a social, ethical commitment or attitude to environmental sustainability and good husbandry. This paper provides an overall understanding of the concept of land administration systems for dealing with rights, restrictions and responsibilities in future spatially enabled government. Finally......Land Administration Systems are the basis for conceptualizing rights, restrictions and responsibilities related to people, policies and places. Property rights are normally concerned with ownership and tenure whereas restrictions usually control use and activities on land. Responsibilities relate...

  13. Numerical evaluation of path-integral solutions to Fokker-Planck equations. II. Restricted stochastic processes

    International Nuclear Information System (INIS)

    Wehner, M.F.

    1983-01-01

    A path-integral solution is derived for processes described by nonlinear Fokker-Plank equations together with externally imposed boundary conditions. This path-integral solution is written in the form of a path sum for small time steps and contains, in addition to the conventional volume integral, a surface integral which incorporates the boundary conditions. A previously developed numerical method, based on a histogram representation of the probability distribution, is extended to a trapezoidal representation. This improved numerical approach is combined with the present path-integral formalism for restricted processes and is show t give accurate results. 35 refs., 5 figs

  14. Multigrid time-accurate integration of Navier-Stokes equations

    Science.gov (United States)

    Arnone, Andrea; Liou, Meng-Sing; Povinelli, Louis A.

    1993-01-01

    Efficient acceleration techniques typical of explicit steady-state solvers are extended to time-accurate calculations. Stability restrictions are greatly reduced by means of a fully implicit time discretization. A four-stage Runge-Kutta scheme with local time stepping, residual smoothing, and multigridding is used instead of traditional time-expensive factorizations. Some applications to natural and forced unsteady viscous flows show the capability of the procedure.

  15. Removing the Restrictions Imposed on Finite State Machines ...

    African Journals Online (AJOL)

    This study determines an effective method of removing the fixed and finite state amount of memory that restricts finite state machines from carrying out compilation jobs that require larger amount of memory. The study is ... The conclusion reviewed the various steps followed and made projections for further reading. Keyword: ...

  16. Steps and dislocations in cubic lyotropic crystals

    International Nuclear Information System (INIS)

    Leroy, S; Pieranski, P

    2006-01-01

    It has been shown recently that lyotropic systems are convenient for studies of faceting, growth or anisotropic surface melting of crystals. All these phenomena imply the active contribution of surface steps and bulk dislocations. We show here that steps can be observed in situ and in real time by means of a new method combining hygroscopy with phase contrast. First results raise interesting issues about the consequences of bicontinuous topology on the structure and dynamical behaviour of steps and dislocations

  17. Step-by-step cyclic processes scheduling

    DEFF Research Database (Denmark)

    Bocewicz, G.; Nielsen, Izabela Ewa; Banaszak, Z.

    2013-01-01

    Automated Guided Vehicles (AGVs) fleet scheduling is one of the big problems in Flexible Manufacturing System (FMS) control. The problem is more complicated when concurrent multi-product manufacturing and resource deadlock avoidance policies are considered. The objective of the research is to pro......Automated Guided Vehicles (AGVs) fleet scheduling is one of the big problems in Flexible Manufacturing System (FMS) control. The problem is more complicated when concurrent multi-product manufacturing and resource deadlock avoidance policies are considered. The objective of the research...... is to provide a declarative model enabling to state a constraint satisfaction problem aimed at AGVs fleet scheduling subject to assumed itineraries of concurrently manufactured product types. In other words, assuming a given layout of FMS’s material handling and production routes of simultaneously manufactured...... orders, the main objective is to provide the declarative framework aimed at conditions allowing one to calculate the AGVs fleet schedule in online mode. An illustrative example of the relevant algebra-like driven step-by-stem cyclic scheduling is provided....

  18. Aging, adiposity, and calorie restriction.

    Science.gov (United States)

    Fontana, Luigi; Klein, Samuel

    2007-03-07

    Excessive calorie intake and subsequent obesity increases the risk of developing chronic disease and decreases life expectancy. In rodent models, calorie restriction with adequate nutrient intake decreases the risk of developing chronic disease and extends maximum life span. To evaluate the physiological and clinical implications of calorie restriction with adequate nutrient intake. Search of PubMed (1966-December 2006) using terms encompassing various aspects of calorie restriction, dietary restriction, aging, longevity, life span, adiposity, and obesity; hand search of journals that focus on obesity, geriatrics, or aging; and search of reference lists of pertinent research and review articles and books. Reviewed reports (both basic science and clinical) included epidemiologic studies, case-control studies, and randomized controlled trials, with quality of data assessed by taking into account publication in a peer-reviewed journal, number of animals or individuals studied, objectivity of measurements, and techniques used to minimize bias. It is not known whether calorie restriction extends maximum life span or life expectancy in lean humans. However, calorie restriction in adult men and women causes many of the same metabolic adaptations that occur in calorie-restricted rodents and monkeys, including decreased metabolic, hormonal, and inflammatory risk factors for diabetes, cardiovascular disease, and possibly cancer. Excessive calorie restriction causes malnutrition and has adverse clinical effects. Calorie restriction in adult men and women causes beneficial metabolic, hormonal, and functional changes, but the precise amount of calorie intake or body fat mass associated with optimal health and maximum longevity in humans is not known. In addition, it is possible that even moderate calorie restriction may be harmful in specific patient populations, such as lean persons who have minimal amounts of body fat.

  19. The Seven Step Strategy

    Science.gov (United States)

    Schaffer, Connie

    2017-01-01

    Many well-intended instructors use Socratic or leveled questioning to facilitate the discussion of an assigned reading. While this engages a few students, most can opt to remain silent. The seven step strategy described in this article provides an alternative to classroom silence and engages all students. Students discuss a single reading as they…

  20. ECO-generation for some restricted classes of compositions

    Directory of Open Access Journals (Sweden)

    Jean-Luc Baril

    2013-04-01

    Full Text Available We study several restricted classes of compositions by giving one-to-one maps between them and different classes of restricted binary strings or pattern avoiding permutations. Inspired by the ECO method \\cite{BDPP99}, new succession rules for these classes are presented. Finally, we obtain generating algorithms in Constant Amortized Time (CAT for theses classes.

  1. Monitoring of fetuses with intrauterine growth restriction: a longitudinal study

    NARCIS (Netherlands)

    Hecher, K.; Bilardo, C. M.; Stigter, R. H.; Ville, Y.; Hackelöer, B. J.; Kok, H. J.; Senat, M. V.; Visser, G. H.

    2001-01-01

    To describe the time sequence of changes in fetal monitoring variables in intrauterine growth restriction and to correlate these findings with fetal outcome at delivery. This was a prospective longitudinal observational multicenter study on 110 singleton pregnancies with growth-restricted fetuses

  2. 37 CFR 1.142 - Requirement for restriction.

    Science.gov (United States)

    2010-07-01

    ... at any time before final action. (b) Claims to the invention or inventions not elected, if not... Inventions in One Application; Restriction § 1.142 Requirement for restriction. (a) If two or more independent and distinct inventions are claimed in a single application, the examiner in an Office action will...

  3. One-step multiplex real-time RT-PCR assay for detecting and genotyping wild-type group A rotavirus strains and vaccine strains (Rotarix® and RotaTeq®) in stool samples

    Science.gov (United States)

    Mijatovic-Rustempasic, Slavica; Esona, Mathew D.; Tam, Ka Ian; Quaye, Osbourne; Bowen, Michael D.

    2016-01-01

    Background. Group A rotavirus (RVA) infection is the major cause of acute gastroenteritis (AGE) in young children worldwide. Introduction of two live-attenuated rotavirus vaccines, RotaTeq® and Rotarix®, has dramatically reduced RVA associated AGE and mortality in developed as well as in many developing countries. High-throughput methods are needed to genotype rotavirus wild-type strains and to identify vaccine strains in stool samples. Quantitative RT-PCR assays (qRT-PCR) offer several advantages including increased sensitivity, higher throughput, and faster turnaround time. Methods. In this study, a one-step multiplex qRT-PCR assay was developed to detect and genotype wild-type strains and vaccine (Rotarix® and RotaTeq®) rotavirus strains along with an internal processing control (Xeno or MS2 RNA). Real-time RT-PCR assays were designed for VP7 (G1, G2, G3, G4, G9, G12) and VP4 (P[4], P[6] and P[8]) genotypes. The multiplex qRT-PCR assay also included previously published NSP3 qRT-PCR for rotavirus detection and Rotarix® NSP2 and RotaTeq® VP6 qRT-PCRs for detection of Rotarix® and RotaTeq® vaccine strains respectively. The multiplex qRT-PCR assay was validated using 853 sequence confirmed stool samples and 24 lab cultured strains of different rotavirus genotypes. By using thermostable rTth polymerase enzyme, dsRNA denaturation, reverse transcription (RT) and amplification (PCR) steps were performed in single tube by uninterrupted thermocycling profile to reduce chances of sample cross contamination and for rapid generation of results. For quantification, standard curves were generated using dsRNA transcripts derived from RVA gene segments. Results. The VP7 qRT-PCRs exhibited 98.8–100% sensitivity, 99.7–100% specificity, 85–95% efficiency and a limit of detection of 4–60 copies per singleplex reaction. The VP7 qRT-PCRs exhibited 81–92% efficiency and limit of detection of 150–600 copies in multiplex reactions. The VP4 qRT-PCRs exhibited 98.8

  4. Efficiently computing exact geodesic loops within finite steps.

    Science.gov (United States)

    Xin, Shi-Qing; He, Ying; Fu, Chi-Wing

    2012-06-01

    Closed geodesics, or geodesic loops, are crucial to the study of differential topology and differential geometry. Although the existence and properties of closed geodesics on smooth surfaces have been widely studied in mathematics community, relatively little progress has been made on how to compute them on polygonal surfaces. Most existing algorithms simply consider the mesh as a graph and so the resultant loops are restricted only on mesh edges, which are far from the actual geodesics. This paper is the first to prove the existence and uniqueness of geodesic loop restricted on a closed face sequence; it contributes also with an efficient algorithm to iteratively evolve an initial closed path on a given mesh into an exact geodesic loop within finite steps. Our proposed algorithm takes only an O(k) space complexity and an O(mk) time complexity (experimentally), where m is the number of vertices in the region bounded by the initial loop and the resultant geodesic loop, and k is the average number of edges in the edge sequences that the evolving loop passes through. In contrast to the existing geodesic curvature flow methods which compute an approximate geodesic loop within a predefined threshold, our method is exact and can apply directly to triangular meshes without needing to solve any differential equation with a numerical solver; it can run at interactive speed, e.g., in the order of milliseconds, for a mesh with around 50K vertices, and hence, significantly outperforms existing algorithms. Actually, our algorithm could run at interactive speed even for larger meshes. Besides the complexity of the input mesh, the geometric shape could also affect the number of evolving steps, i.e., the performance. We motivate our algorithm with an interactive shape segmentation example shown later in the paper.

  5. Comparison of step-by-step kinematics of resisted, assisted and unloaded 20-m sprint runs.

    Science.gov (United States)

    van den Tillaar, Roland; Gamble, Paul

    2018-03-26

    This investigation examined step-by-step kinematics of sprint running acceleration. Using a randomised counterbalanced approach, 37 female team handball players (age 17.8 ± 1.6 years, body mass 69.6 ± 9.1 kg, height 1.74 ± 0.06 m) performed resisted, assisted and unloaded 20-m sprints within a single session. 20-m sprint times and step velocity, as well as step length, step frequency, contact and flight times of each step were evaluated for each condition with a laser gun and an infrared mat. Almost all measured parameters were altered for each step under the resisted and assisted sprint conditions (η 2  ≥ 0.28). The exception was step frequency, which did not differ between assisted and normal sprints. Contact time, flight time and step frequency at almost each step were different between 'fast' vs. 'slow' sub-groups (η 2  ≥ 0.22). Nevertheless overall both groups responded similarly to the respective sprint conditions. No significant differences in step length were observed between groups for the respective condition. It is possible that continued exposure to assisted sprinting might allow the female team-sports players studied to adapt their coordination to the 'over-speed' condition and increase step frequency. It is notable that step-by-step kinematics in these sprints were easy to obtain using relatively inexpensive equipment with possibilities of direct feedback.

  6. The future of irrigated agriculture under environmental flow requirements restrictions

    Science.gov (United States)

    Pastor, Amandine; Palazzo, Amanda; Havlik, Petr; Kabat, Pavel; Obersteiner, Michael; Ludwig, Fulco

    2016-04-01

    Water is not an infinite resource and demand from irrigation, household and industry is constantly increasing. This study focused on including global water availability including environmental flow requirements with water withdrawal from irrigation and other sectors at a monthly time-step in the GLOBIOM model. This model allows re-adjustment of land-use allocation, crop management, consumption and international trade. The GLOBIOM model induces an endogenous change in water price depending on water supply and demand. In this study, the focus was on how the inclusion of water resources affects land-use and, in particular, how global change will influence repartition of irrigated and rainfed lands at global scale. We used the climate change scenario including a radiative forcing of 8.5 W/m2 (RCP8.5), the socio-economic scenario (SSP2: middle-of-road), and the environmental flow method based on monthly flow allocation (the Variable Monthly Flow method) with high and low restrictions. Irrigation withdrawals were adjusted to a monthly time-step to account for biophysical water limitations at finer time resolution. Our results show that irrigated land might decrease up to 40% on average depending on the choice of EFR restrictions. Several areas were identified as future hot-spots of water stress such as the Mediterranean and Middle-East regions. Other countries were identified to be in safe position in terms of water stress such as North-European countries. Re-allocation of rainfed and irrigated land might be useful information for land-use planners and water managers at an international level to decide on appropriate legislations on climate change mitigation/adaptation when exposure and sensitivity to climate change is high and/or on adaptation measures to face increasing water demand. For example, some countries are likely to adopt measures to increase their water use efficiencies (irrigation system, soil and water conservation practices) to face water shortages, while

  7. Development of a Real-Time PCR for a Sensitive One-Step Coprodiagnosis Allowing both the Identification of Carnivore Feces and the Detection of Toxocara spp. and Echinococcus multilocularis

    Science.gov (United States)

    Umhang, Gérald; Poulle, Marie-Lazarine; Millon, Laurence

    2016-01-01

    Studying the environmental occurrence of parasites of concern for humans and animals based on coprosamples is an expanding field of work in epidemiology and the ecology of health. Detecting and quantifying Toxocara spp. and Echinococcus multilocularis, two predominant zoonotic helminths circulating in European carnivores, in feces may help to better target measures for prevention. A rapid, sensitive, and one-step quantitative PCR (qPCR) allowing detection of E. multilocularis and Toxocara spp. was developed in the present study, combined with a host fecal test based on the identification of three carnivores (red fox, dog, and cat) involved in the life cycles of these parasites. A total of 68 coprosamples were collected from identified specimens from Vulpes vulpes, Canis lupus familiaris, Canis lupus, Felis silvestris catus, Meles meles, Martes foina, and Martes martes. With DNA coprosamples, real-time PCR was performed in duplex with a qPCR inhibitor control specifically designed for this study. All the coprosample host identifications were confirmed by qPCR combined with sequencing, and parasites were detected and confirmed (E. multilocularis in red foxes and Toxocara cati in cats; 16% of samples presented inhibition). By combining parasite detection and quantification, the host fecal test, and a new qPCR inhibitor control, we created a technique with a high sensitivity that may considerably improve environmental studies of pathogens. PMID:26969697

  8. Development of a Real-Time PCR for a Sensitive One-Step Coprodiagnosis Allowing both the Identification of Carnivore Feces and the Detection of Toxocara spp. and Echinococcus multilocularis.

    Science.gov (United States)

    Knapp, Jenny; Umhang, Gérald; Poulle, Marie-Lazarine; Millon, Laurence

    2016-05-15

    Studying the environmental occurrence of parasites of concern for humans and animals based on coprosamples is an expanding field of work in epidemiology and the ecology of health. Detecting and quantifying Toxocara spp. and Echinococcus multilocularis, two predominant zoonotic helminths circulating in European carnivores, in feces may help to better target measures for prevention. A rapid, sensitive, and one-step quantitative PCR (qPCR) allowing detection of E. multilocularis and Toxocara spp. was developed in the present study, combined with a host fecal test based on the identification of three carnivores (red fox, dog, and cat) involved in the life cycles of these parasites. A total of 68 coprosamples were collected from identified specimens from Vulpes vulpes, Canis lupus familiaris, Canis lupus, Felis silvestris catus, Meles meles, Martes foina, and Martes martes With DNA coprosamples, real-time PCR was performed in duplex with a qPCR inhibitor control specifically designed for this study. All the coprosample host identifications were confirmed by qPCR combined with sequencing, and parasites were detected and confirmed (E. multilocularis in red foxes and Toxocara cati in cats; 16% of samples presented inhibition). By combining parasite detection and quantification, the host fecal test, and a new qPCR inhibitor control, we created a technique with a high sensitivity that may considerably improve environmental studies of pathogens. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  9. Linear step drive

    International Nuclear Information System (INIS)

    Haniger, L.; Elger, R.; Kocandrle, L.; Zdebor, J.

    1986-01-01

    A linear step drive is described developed in Czechoslovak-Soviet cooperation and intended for driving WWER-1000 control rods. The functional principle is explained of the motor and the mechanical and electrical parts of the drive, power control, and the indicator of position are described. The motor has latches situated in the reactor at a distance of 3 m from magnetic armatures, it has a low structural height above the reactor cover, which suggests its suitability for seismic localities. Its magnetic circuits use counterpoles; the mechanical shocks at the completion of each step are damped using special design features. The position indicator is of a special design and evaluates motor position within ±1% of total travel. A drive diagram and the flow chart of both the control electronics and the position indicator are presented. (author) 4 figs

  10. Computational Abstraction Steps

    DEFF Research Database (Denmark)

    Thomsen, Lone Leth; Thomsen, Bent; Nørmark, Kurt

    2010-01-01

    and class instantiations. Our teaching experience shows that many novice programmers find it difficult to write programs with abstractions that materialise to concrete objects later in the development process. The contribution of this paper is the idea of initiating a programming process by creating...... or capturing concrete values, objects, or actions. As the next step, some of these are lifted to a higher level by computational means. In the object-oriented paradigm the target of such steps is classes. We hypothesise that the proposed approach primarily will be beneficial to novice programmers or during...... the exploratory phase of a program development process. In some specific niches it is also expected that our approach will benefit professional programmers....

  11. Robust Detection of Stepping-Stone Attacks

    National Research Council Canada - National Science Library

    He, Ting; Tong, Lang

    2006-01-01

    The detection of encrypted stepping-stone attack is considered. Besides encryption and padding, the attacker is capable of inserting chaff packets and perturbing packet timing and transmission order...

  12. Step 3: Manage Your Diabetes

    Science.gov (United States)

    ... please turn JavaScript on. Feature: Type 2 Diabetes Step 3: Manage Your Diabetes Past Issues / Fall 2014 ... 2 Diabetes" Articles Diabetes Is Serious But Manageable / Step 1: Learn About Diabetes / Step 2: Know Your ...

  13. How Harmful are Adaptation Restrictions

    OpenAIRE

    Bruin, de, K.C.; Dellink, R.B.

    2009-01-01

    The dominant assumption in economic models of climate policy remains that adaptation will be implemented in an optimal manner. There are, however, several reasons why optimal levels of adaptation may not be attainable. This paper investigates the effects of suboptimal levels of adaptation, i.e. adaptation restrictions, on the composition and level of climate change costs and on welfare. Several adaptation restrictions are identified and then simulated in a revised DICE model, extended with ad...

  14. Small steps for hydro

    International Nuclear Information System (INIS)

    Wicke, Peter

    1998-01-01

    The government in Peru has decided to utilise its gas reserves and restrict hydro to relatively small schemes. A number of reasons for the decision are given. In 1997, the Shell-Mobile-Bechtel-COSAPI consortium was formed and agreements were signed regarding exploiting Gas de Camisea. The country's energy needs to 2010 are being assessed. It is likely that by 2001 the whole of south Peru will be receiving gas from Camisea. The Peru situation is discussed under the headings of (i) existing capacity, (ii) growing demands, (iii) a history of hydro in Peru, (iv) electrification and SHP and (v) outlook. The future for Peru's electric energy development is bright. While most of its new power capacity will come from natural gas, the small hydros also have a part to play. A stronger commitment of national and regional political authorities to consider supplies outside the big cities is said to be needed. (UK)

  15. [The investigation of control mechanisms of stepping rhythm in human in the air-stepping conditions during passive and voluntary leg movements].

    Science.gov (United States)

    Solopova, I A; Selionon, V A; Grishin, A A

    2010-01-01

    In unloading condition the degree of activation of the central stepping program was investigated during passive leg movements in healthy subjects, as well as the excitability of spinal motoneurons during passive and voluntary stepping movement. Passive stepping movements with characteristics maximally approximated to those during voluntary stepping were accomplished by experimenter. The comparison of the muscle activity bursts during voluntary and imposed movements was made. In addition to that the influence of artificially created loading onto the foot to the leg movement characteristics was analyzed. Spinal motoneuron excitability was estimated by means of evaluation of amplitude modulation of the soleus H-reflex. The changes of H-reflexes under the fixation of knee or hip joints were also studied. In majority of subjects the passive movements were accompanied by bursts of EMG activity of hip muscles (and sometimes of knee muscles), which timing during step cycle was coincided with burst timing of voluntary step cycle. In many cases the bursts of EMG activity during passive movements exceeded activity in homonymous muscles during voluntary stepping. The foot loading imitation exerted essential influence on distal parts of moving extremity during voluntary as well passive movements, that was expressed in the appearance of movements in the ankle joint and accompanied by emergence and increasing of phasic EMG activity of shank muscles. The excitability of motoneurons during passive movements was greater then during voluntary ones. The changes and modulation of H-reflex throughout the step cycle without restriction of joint mobility and during exclusion of hip joint mobility were similar. The knee joint fixation exerted the greater influence. It is supposed that imposed movements activate the same mechanisms of rhythm generation as a supraspinal commands during voluntary movements. In the conditions of passive movements the presynaptic inhibition depend on afferent

  16. Recovery of forward stepping in spinal cord injured patients does not transfer to untrained backward stepping.

    Science.gov (United States)

    Grasso, Renato; Ivanenko, Yuri P; Zago, Myrka; Molinari, Marco; Scivoletto, Giorgio; Lacquaniti, Francesco

    2004-08-01

    Six spinal cord injured (SCI) patients were trained to step on a treadmill with body-weight support for 1.5-3 months. At the end of training, foot motion recovered the shape and the step-by-step reproducibility that characterize normal gait. They were then asked to step backward on the treadmill belt that moved in the opposite direction relative to standard forward training. In contrast to healthy subjects, who can immediately reverse the direction of walking by time-reversing the kinematic waveforms, patients were unable to step backward. Similarly patients were unable to perform another untrained locomotor task, namely stepping in place on the idle treadmill. Two patients who were trained to step backward for 2-3 weeks were able to develop control of foot motion appropriate for this task. The results show that locomotor improvement does not transfer to untrained tasks, thus supporting the idea of task-dependent plasticity in human locomotor networks.

  17. Four-dimensional dose distributions of step-and-shoot IMRT delivered with real-time tumor tracking for patients with irregular breathing: Constant dose rate vs dose rate regulation

    International Nuclear Information System (INIS)

    Yang Xiaocheng; Han-Oh, Sarah; Gui Minzhi; Niu Ying; Yu, Cedric X.; Yi Byongyong

    2012-01-01

    Purpose: Dose-rate-regulated tracking (DRRT) is a tumor tracking strategy that programs the MLC to track the tumor under regular breathing and adapts to breathing irregularities during delivery using dose rate regulation. Constant-dose-rate tracking (CDRT) is a strategy that dynamically repositions the beam to account for intrafractional 3D target motion according to real-time information of target location obtained from an independent position monitoring system. The purpose of this study is to illustrate the differences in the effectiveness and delivery accuracy between these two tracking methods in the presence of breathing irregularities. Methods: Step-and-shoot IMRT plans optimized at a reference phase were extended to remaining phases to generate 10-phased 4D-IMRT plans using segment aperture morphing (SAM) algorithm, where both tumor displacement and deformation were considered. A SAM-based 4D plan has been demonstrated to provide better plan quality than plans not considering target deformation. However, delivering such a plan requires preprogramming of the MLC aperture sequence. Deliveries of the 4D plans using DRRT and CDRT tracking approaches were simulated assuming the breathing period is either shorter or longer than the planning day, for 4 IMRT cases: two lung and two pancreatic cases with maximum GTV centroid motion greater than 1 cm were selected. In DRRT, dose rate was regulated to speed up or slow down delivery as needed such that each planned segment is delivered at the planned breathing phase. In CDRT, MLC is separately controlled to follow the tumor motion, but dose rate was kept constant. In addition to breathing period change, effect of breathing amplitude variation on target and critical tissue dose distribution is also evaluated. Results: Delivery of preprogrammed 4D plans by the CDRT method resulted in an average of 5% increase in target dose and noticeable increase in organs at risk (OAR) dose when patient breathing is either 10% faster or

  18. Comparison of step-by-step kinematics in repeated 30m sprints in female soccer players.

    Science.gov (United States)

    van den Tillaar, Roland

    2018-01-04

    The aim of this study was to compare kinematics in repeated 30m sprints in female soccer players. Seventeen subjects performed seven 30m sprints every 30s in one session. Kinematics were measured with an infrared contact mat and laser gun, and running times with an electronic timing device. The main findings were that sprint times increased in the repeated sprint ability test. The main changes in kinematics during the repeated sprint ability test were increased contact time and decreased step frequency, while no change in step length was observed. The step velocity increased in almost each step until the 14, which occurred around 22m. After this, the velocity was stable until the last step, when it decreased. This increase in step velocity was mainly caused by the increased step length and decreased contact times. It was concluded that the fatigue induced in repeated 30m sprints in female soccer players resulted in decreased step frequency and increased contact time. Employing this approach in combination with a laser gun and infrared mat for 30m makes it very easy to analyse running kinematics in repeated sprints in training. This extra information gives the athlete, coach and sports scientist the opportunity to give more detailed feedback and help to target these changes in kinematics better to enhance repeated sprint performance.

  19. SYSTEMATIZATION OF THE BASIC STEPS OF THE STEP-AEROBICS

    Directory of Open Access Journals (Sweden)

    Darinka Korovljev

    2011-03-01

    Full Text Available Following the development of the powerful sport industry, in front of us appeared a lot of new opportunities for creating of the new programmes of exercising with certain requisites. One of such programmes is certainly step-aerobics. Step-aerobics can be defined as a type of aerobics consisting of the basic aerobic steps (basic steps applied in exercising on stepper (step bench, with a possibility to regulate its height. Step-aerobics itself can be divided into several groups, depending on the following: type of music, working methods and adopted knowledge of the attendants. In this work, the systematization of the basic steps in step-aerobics was made on the basis of the following criteria: steps origin, number of leg motions in stepping and relating the body support at the end of the step. Systematization of the basic steps of the step-aerobics is quite significant for making a concrete review of the existing basic steps, thus making creation of the step-aerobics lesson easier

  20. Cuba: U.S. Restrictions on Travel and Legislative Initiatives

    National Research Council Canada - National Science Library

    Sullivan, Mark P

    2003-01-01

    .... In March 2003, the Administration eased restrictions on those visiting close family members in Cuba, while at the same time it eliminated travel for people-to-people educational exchanges unrelated...

  1. Efficiency improvement in proton dose calculations with an equivalent restricted stopping power formalism

    Science.gov (United States)

    Maneval, Daniel; Bouchard, Hugo; Ozell, Benoît; Després, Philippe

    2018-01-01

    The equivalent restricted stopping power formalism is introduced for proton mean energy loss calculations under the continuous slowing down approximation. The objective is the acceleration of Monte Carlo dose calculations by allowing larger steps while preserving accuracy. The fractional energy loss per step length ɛ was obtained with a secant method and a Gauss-Kronrod quadrature estimation of the integral equation relating the mean energy loss to the step length. The midpoint rule of the Newton-Cotes formulae was then used to solve this equation, allowing the creation of a lookup table linking ɛ to the equivalent restricted stopping power L eq, used here as a key physical quantity. The mean energy loss for any step length was simply defined as the product of the step length with L eq. Proton inelastic collisions with electrons were added to GPUMCD, a GPU-based Monte Carlo dose calculation code. The proton continuous slowing-down was modelled with the L eq formalism. GPUMCD was compared to Geant4 in a validation study where ionization processes alone were activated and a voxelized geometry was used. The energy straggling was first switched off to validate the L eq formalism alone. Dose differences between Geant4 and GPUMCD were smaller than 0.31% for the L eq formalism. The mean error and the standard deviation were below 0.035% and 0.038% respectively. 99.4 to 100% of GPUMCD dose points were consistent with a 0.3% dose tolerance. GPUMCD 80% falloff positions (R80 ) matched Geant’s R80 within 1 μm. With the energy straggling, dose differences were below 2.7% in the Bragg peak falloff and smaller than 0.83% elsewhere. The R80 positions matched within 100 μm. The overall computation times to transport one million protons with GPUMCD were 31-173 ms. Under similar conditions, Geant4 computation times were 1.4-20 h. The L eq formalism led to an intrinsic efficiency gain factor ranging between 30-630, increasing with the prescribed accuracy of simulations. The

  2. Host Cell Restriction Factors that Limit Influenza A Infection

    Directory of Open Access Journals (Sweden)

    Fernando Villalón-Letelier

    2017-12-01

    Full Text Available Viral infection of different cell types induces a unique spectrum of host defence genes, including interferon-stimulated genes (ISGs and genes encoding other proteins with antiviral potential. Although hundreds of ISGs have been described, the vast majority have not been functionally characterised. Cellular proteins with putative antiviral activity (hereafter referred to as “restriction factors” can target various steps in the virus life-cycle. In the context of influenza virus infection, restriction factors have been described that target virus entry, genomic replication, translation and virus release. Genome wide analyses, in combination with ectopic overexpression and/or gene silencing studies, have accelerated the identification of restriction factors that are active against influenza and other viruses, as well as providing important insights regarding mechanisms of antiviral activity. Herein, we review current knowledge regarding restriction factors that mediate anti-influenza virus activity and consider the viral countermeasures that are known to limit their impact. Moreover, we consider the strengths and limitations of experimental approaches to study restriction factors, discrepancies between in vitro and in vivo studies, and the potential to exploit restriction factors to limit disease caused by influenza and other respiratory viruses.

  3. Influence of step complexity and presentation style on step performance of computerized emergency operating procedures

    Energy Technology Data Exchange (ETDEWEB)

    Xu Song [Department of Industrial Engineering, Tsinghua University, Beijing 100084 (China); Li Zhizhong [Department of Industrial Engineering, Tsinghua University, Beijing 100084 (China)], E-mail: zzli@tsinghua.edu.cn; Song Fei; Luo Wei; Zhao Qianyi; Salvendy, Gavriel [Department of Industrial Engineering, Tsinghua University, Beijing 100084 (China)

    2009-02-15

    With the development of information technology, computerized emergency operating procedures (EOPs) are taking the place of paper-based ones. However, ergonomics issues of computerized EOPs have not been studied adequately since the industrial practice is quite limited yet. This study examined the influence of step complexity and presentation style of EOPs on step performance. A simulated computerized EOP system was developed in two presentation styles: Style A: one- and two-dimensional flowcharts combination; Style B: two-dimensional flowchart and success logic tree combination. Step complexity was quantified by a complexity measure model based on an entropy concept. Forty subjects participated in the experiment of EOP execution using the simulated system. The results of data analysis on the experiment data indicate that step complexity and presentation style could significantly influence step performance (both step error rate and operation time). Regression models were also developed. The regression analysis results imply that operation time of a step could be well predicted by step complexity while step error rate could only partly predicted by it. The result of a questionnaire investigation implies that step error rate was influenced not only by the operation task itself but also by other human factors. These findings may be useful for the design and assessment of computerized EOPs.

  4. Group Analysis in FieldTrip of Time-Frequency Responses: A Pipeline for Reproducibility at Every Step of Processing, Going From Individual Sensor Space Representations to an Across-Group Source Space Representation

    Directory of Open Access Journals (Sweden)

    Lau M. Andersen

    2018-05-01

    Full Text Available An important aim of an analysis pipeline for magnetoencephalographic (MEG data is that it allows for the researcher spending maximal effort on making the statistical comparisons that will answer his or her questions. The example question being answered here is whether the so-called beta rebound differs between novel and repeated stimulations. Two analyses are presented: going from individual sensor space representations to, respectively, an across-group sensor space representation and an across-group source space representation. The data analyzed are neural responses to tactile stimulations of the right index finger in a group of 20 healthy participants acquired from an Elekta Neuromag System. The processing steps covered for the first analysis are MaxFiltering the raw data, defining, preprocessing and epoching the data, cleaning the data, finding and removing independent components related to eye blinks, eye movements and heart beats, calculating participants' individual evoked responses by averaging over epoched data and subsequently removing the average response from single epochs, calculating a time-frequency representation and baselining it with non-stimulation trials and finally calculating a grand average, an across-group sensor space representation. The second analysis starts from the grand average sensor space representation and after identification of the beta rebound the neural origin is imaged using beamformer source reconstruction. This analysis covers reading in co-registered magnetic resonance images, segmenting the data, creating a volume conductor, creating a forward model, cutting out MEG data of interest in the time and frequency domains, getting Fourier transforms and estimating source activity with a beamformer model where power is expressed relative to MEG data measured during periods of non-stimulation. Finally, morphing the source estimates onto a common template and performing group-level statistics on the data are

  5. Advances in sequential data assimilation and numerical weather forecasting: An Ensemble Transform Kalman-Bucy Filter, a study on clustering in deterministic ensemble square root filters, and a test of a new time stepping scheme in an atmospheric model

    Science.gov (United States)

    Amezcua, Javier

    in the mean value of the function. Using statistical significance tests both at the local and field level, it is shown that the climatology of the SPEEDY model is not modified by the changed time stepping scheme; hence, no retuning of the parameterizations is required. It is found the accuracy of the medium-term forecasts is increased by using the RAW filter.

  6. SPAR-H Step-by-Step Guidance

    International Nuclear Information System (INIS)

    Galyean, W.J.; Whaley, A.M.; Kelly, D.L.; Boring, R.L.

    2011-01-01

    This guide provides step-by-step guidance on the use of the SPAR-H method for quantifying Human Failure Events (HFEs). This guide is intended to be used with the worksheets provided in: 'The SPAR-H Human Reliability Analysis Method,' NUREG/CR-6883, dated August 2005. Each step in the process of producing a Human Error Probability (HEP) is discussed. These steps are: Step-1, Categorizing the HFE as Diagnosis and/or Action; Step-2, Rate the Performance Shaping Factors; Step-3, Calculate PSF-Modified HEP; Step-4, Accounting for Dependence, and; Step-5, Minimum Value Cutoff. The discussions on dependence are extensive and include an appendix that describes insights obtained from the psychology literature.

  7. SPAR-H Step-by-Step Guidance

    Energy Technology Data Exchange (ETDEWEB)

    W. J. Galyean; A. M. Whaley; D. L. Kelly; R. L. Boring

    2011-05-01

    This guide provides step-by-step guidance on the use of the SPAR-H method for quantifying Human Failure Events (HFEs). This guide is intended to be used with the worksheets provided in: 'The SPAR-H Human Reliability Analysis Method,' NUREG/CR-6883, dated August 2005. Each step in the process of producing a Human Error Probability (HEP) is discussed. These steps are: Step-1, Categorizing the HFE as Diagnosis and/or Action; Step-2, Rate the Performance Shaping Factors; Step-3, Calculate PSF-Modified HEP; Step-4, Accounting for Dependence, and; Step-5, Minimum Value Cutoff. The discussions on dependence are extensive and include an appendix that describes insights obtained from the psychology literature.

  8. Exponential stability of continuous-time and discrete-time bidirectional associative memory networks with delays

    International Nuclear Information System (INIS)

    Liang Jinling; Cao Jinde

    2004-01-01

    First, convergence of continuous-time Bidirectional Associative Memory (BAM) neural networks are studied. By using Lyapunov functionals and some analysis technique, the delay-independent sufficient conditions are obtained for the networks to converge exponentially toward the equilibrium associated with the constant input sources. Second, discrete-time analogues of the continuous-time BAM networks are formulated and studied. It is shown that the convergence characteristics of the continuous-time systems are preserved by the discrete-time analogues without any restriction imposed on the uniform discretionary step size. An illustrative example is given to demonstrate the effectiveness of the obtained results

  9. Compensatory stepping responses in individuals with stroke: a pilot study.

    Science.gov (United States)

    Lakhani, Bimal; Mansfield, Avril; Inness, Elizabeth L; McIlroy, William E

    2011-05-01

    Impaired postural control and a high incidence of falls are commonly observed following stroke. Compensatory stepping responses are critical to reactive balance control. We hypothesize that, following a stroke, individuals with unilateral limb dyscontrol will be faced with the unique challenge of controlling such rapid stepping reactions that may eventually be linked to the high rate of falling. The objectives of this exploratory pilot study were to investigate compensatory stepping in individuals poststroke with regard to: (1) choice of initial stepping limb (paretic or non-paretic); (2) step characteristics; and (3) differences in step characteristics when the initial step is taken with the paretic vs. the non-paretic limb. Four subjects following stroke (38-165 days post) and 11 healthy young adults were recruited. Anterior and posterior perturbations were delivered by using a weight drop system. Force plates recorded centre-of-pressure excursion prior to the onset of stepping and step timing. Of the four subjects, three only attempted to step with their non-paretic limb and one stepped with either limb. Time to foot-off was generally slow, whereas step onset time and swing time were comparable to healthy controls. Two of the four subjects executed multistep responses in every trial, and attempts to force stepping with the paretic limb were unsuccessful in three of the four subjects. Despite high clinical balance scores, these individuals with stroke demonstrated impaired compensatory stepping responses, suggesting that current clinical evaluations might not accurately reflect reactive balance control in this population.

  10. Boris push with spatial stepping

    International Nuclear Information System (INIS)

    Penn, G; Stoltz, P H; Cary, J R; Wurtele, J

    2003-01-01

    The Boris push is commonly used in plasma physics simulations because of its speed and stability. It is second-order accurate, requires only one field evaluation per time step, and has good conservation properties. However, for accelerator simulations it is convenient to propagate particles in z down a changing beamline. A 'spatial Boris push' algorithm has been developed which is similar to the Boris push but uses a spatial coordinate as the independent variable, instead of time. This scheme is compared to the fourth-order Runge-Kutta algorithm, for two simplified muon beam lattices: a uniform solenoid field, and a 'FOFO' lattice where the solenoid field varies sinusoidally along the axis. Examination of the canonical angular momentum, which should be conserved in axisymmetric systems, shows that the spatial Boris push improves accuracy over long distances

  11. Telomere Restriction Fragment (TRF) Analysis.

    Science.gov (United States)

    Mender, Ilgen; Shay, Jerry W

    2015-11-20

    While telomerase is expressed in ~90% of primary human tumors, most somatic tissue cells except transiently proliferating stem-like cells do not have detectable telomerase activity (Shay and Wright, 1996; Shay and Wright, 2001). Telomeres progressively shorten with each cell division in normal cells, including proliferating stem-like cells, due to the end replication (lagging strand synthesis) problem and other causes such as oxidative damage, therefore all somatic cells have limited cell proliferation capacity (Hayflick limit) (Hayflick and Moorhead, 1961; Olovnikov, 1973). The progressive telomere shortening eventually leads to growth arrest in normal cells, which is known as replicative senescence (Shay et al. , 1991). Once telomerase is activated in cancer cells, telomere length is stabilized by the addition of TTAGGG repeats to the end of chromosomes, thus enabling the limitless continuation of cell division (Shay and Wright, 1996; Shay and Wright, 2001). Therefore, the link between aging and cancer can be partially explained by telomere biology. There are many rapid and convenient methods to study telomere biology such as Telomere Restriction Fragment (TRF), Telomere Repeat Amplification Protocol (TRAP) (Mender and Shay, 2015b) and Telomere dysfunction Induced Foci (TIF) analysis (Mender and Shay, 2015a). In this protocol paper we describe Telomere Restriction Fragment (TRF) analysis to determine average telomeric length of cells. Telomeric length can be indirectly measured by a technique called Telomere Restriction Fragment analysis (TRF). This technique is a modified Southern blot, which measures the heterogeneous range of telomere lengths in a cell population using the length distribution of the terminal restriction fragments (Harley et al. , 1990; Ouellette et al. , 2000). This method can be used in eukaryotic cells. The description below focuses on the measurement of human cancer cells telomere length. The principle of this method relies on the lack of

  12. Hippocampus discovery First steps

    Directory of Open Access Journals (Sweden)

    Eliasz Engelhardt

    Full Text Available The first steps of the discovery, and the main discoverers, of the hippocampus are outlined. Arantius was the first to describe a structure he named "hippocampus" or "white silkworm". Despite numerous controversies and alternate designations, the term hippocampus has prevailed until this day as the most widely used term. Duvernoy provided an illustration of the hippocampus and surrounding structures, considered the first by most authors, which appeared more than one and a half century after Arantius' description. Some authors have identified other drawings and texts which they claim predate Duvernoy's depiction, in studies by Vesalius, Varolio, Willis, and Eustachio, albeit unconvincingly. Considering the definition of the hippocampal formation as comprising the hippocampus proper, dentate gyrus and subiculum, Arantius and Duvernoy apparently described the gross anatomy of this complex. The pioneering studies of Arantius and Duvernoy revealed a relatively small hidden formation that would become one of the most valued brain structures.

  13. Astronomical sketching a step-by-step introduction

    CERN Document Server

    Handy, Richard; Perez, Jeremy; Rix, Erika; Robbins, Sol

    2007-01-01

    This book presents the amateur with fine examples of astronomical sketches and step-by-step tutorials in each medium, from pencil to computer graphics programs. This unique book can teach almost anyone to create beautiful sketches of celestial objects.

  14. Growth assessment in diagnosis of Fetal Growth Restriction. Review

    OpenAIRE

    Albu, AR; Horhoianu, IA; Dumitrascu, MC; Horhoianu, V

    2014-01-01

    Abstract The assessment of fetal growth represents a fundamental step towards the identification of the true growth restricted fetus that is associated to important perinatal morbidity and mortality. The possible ways of detecting abnormal fetal growth are taken into consideration in this review and their strong and weak points are discussed. An important debate still remains about how to discriminate between the physiologically small fetus that does not require special surveillance and the t...

  15. Effect of One-Step and Multi-Steps Polishing System on Enamel Roughness

    Directory of Open Access Journals (Sweden)

    Cynthia Sumali

    2013-07-01

    Full Text Available Normal 0 false false false MicrosoftInternetExplorer4 The final procedures of orthodontic treatment are bracket debonding and cleaning the remaining adhesive. Multi-step polishing system is the most common method used. The disadvantage of that system is long working time, because of the stages that should be done. Therefore, dental material manufacturer make an improvement to the system, to reduce several stages into one stage only. This new system is known as one-step polishing system. Objective: To compare the effect of one-step and multi-step polishing system on enamel roughness after orthodontic bracket debonding. Methods: Randomized control trial was conducted included twenty-eight maxillary premolar randomized into two polishing system; one-step OptraPol (Ivoclar, Vivadent and multi-step AstroPol (Ivoclar, Vivadent. After bracket debonding, the remaining adhesive on each group was cleaned by subjective polishing system for ninety seconds using low speed handpiece. The enamel roughness was subjected to profilometer, registering two roughness parameters (Ra, Rz. Independent t-test was used to analyze the mean score of enamel roughness in each group. Results: There was no significant difference of enamel roughness between one-step and multi-step polishing system (p>0.005. Conclusion: One-step polishing system can produce a similar enamel roughness to multi-step polishing system after bracket debonding and adhesive cleaning.DOI: 10.14693/jdi.v19i3.136

  16. Gentile statistics and restricted partitions

    Indian Academy of Sciences (India)

    In a recent paper (Tran et al, Ann. Phys. 311, 204 (2004)), some asymptotic number theoretical results on the partitioning of an integer were derived exploiting its connection to the quantum density of states of a many-particle system. We generalise these results to obtain an asymptotic formula for the restricted or coloured ...

  17. A step-defined sedentary lifestyle index: <5000 steps/day.

    Science.gov (United States)

    Tudor-Locke, Catrine; Craig, Cora L; Thyfault, John P; Spence, John C

    2013-02-01

    Step counting (using pedometers or accelerometers) is widely accepted by researchers, practitioners, and the general public. Given the mounting evidence of the link between low steps/day and time spent in sedentary behaviours, how few steps/day some populations actually perform, and the growing interest in the potentially deleterious effects of excessive sedentary behaviours on health, an emerging question is "How many steps/day are too few?" This review examines the utility, appropriateness, and limitations of using a reoccurring candidate for a step-defined sedentary lifestyle index: 10 000) to lower (sedentary lifestyle index for adults is appropriate for researchers and practitioners and for communicating with the general public. There is little evidence to advocate any specific value indicative of a step-defined sedentary lifestyle index in children and adolescents.

  18. Controlling pandemic flu: the value of international air travel restrictions.

    Directory of Open Access Journals (Sweden)

    Joshua M Epstein

    2007-05-01

    Full Text Available Planning for a possible influenza pandemic is an extremely high priority, as social and economic effects of an unmitigated pandemic would be devastating. Mathematical models can be used to explore different scenarios and provide insight into potential costs, benefits, and effectiveness of prevention and control strategies under consideration.A stochastic, equation-based epidemic model is used to study global transmission of pandemic flu, including the effects of travel restrictions and vaccination. Economic costs of intervention are also considered. The distribution of First Passage Times (FPT to the United States and the numbers of infected persons in metropolitan areas worldwide are studied assuming various times and locations of the initial outbreak. International air travel restrictions alone provide a small delay in FPT to the U.S. When other containment measures are applied at the source in conjunction with travel restrictions, delays could be much longer. If in addition, control measures are instituted worldwide, there is a significant reduction in cases worldwide and specifically in the U.S. However, if travel restrictions are not combined with other measures, local epidemic severity may increase, because restriction-induced delays can push local outbreaks into high epidemic season. The per annum cost to the U.S. economy of international and major domestic air passenger travel restrictions is minimal: on the order of 0.8% of Gross National Product.International air travel restrictions may provide a small but important delay in the spread of a pandemic, especially if other disease control measures are implemented during the afforded time. However, if other measures are not instituted, delays may worsen regional epidemics by pushing the outbreak into high epidemic season. This important interaction between policy and seasonality is only evident with a global-scale model. Since the benefit of travel restrictions can be substantial while

  19. STEP and fundamental physics

    Science.gov (United States)

    Overduin, James; Everitt, Francis; Worden, Paul; Mester, John

    2012-09-01

    The Satellite Test of the Equivalence Principle (STEP) will advance experimental limits on violations of Einstein's equivalence principle from their present sensitivity of two parts in 1013 to one part in 1018 through multiple comparison of the motions of four pairs of test masses of different compositions in a drag-free earth-orbiting satellite. We describe the experiment, its current status and its potential implications for fundamental physics. Equivalence is at the heart of general relativity, our governing theory of gravity and violations are expected in most attempts to unify this theory with the other fundamental interactions of physics, as well as in many theoretical explanations for the phenomenon of dark energy in cosmology. Detection of such a violation would be equivalent to the discovery of a new force of nature. A null result would be almost as profound, pushing upper limits on any coupling between standard-model fields and the new light degrees of freedom generically predicted by these theories down to unnaturally small levels.

  20. STEP and fundamental physics

    International Nuclear Information System (INIS)

    Overduin, James; Everitt, Francis; Worden, Paul; Mester, John

    2012-01-01

    The Satellite Test of the Equivalence Principle (STEP) will advance experimental limits on violations of Einstein's equivalence principle from their present sensitivity of two parts in 10 13 to one part in 10 18 through multiple comparison of the motions of four pairs of test masses of different compositions in a drag-free earth-orbiting satellite. We describe the experiment, its current status and its potential implications for fundamental physics. Equivalence is at the heart of general relativity, our governing theory of gravity and violations are expected in most attempts to unify this theory with the other fundamental interactions of physics, as well as in many theoretical explanations for the phenomenon of dark energy in cosmology. Detection of such a violation would be equivalent to the discovery of a new force of nature. A null result would be almost as profound, pushing upper limits on any coupling between standard-model fields and the new light degrees of freedom generically predicted by these theories down to unnaturally small levels. (paper)

  1. One-step microlithography

    Science.gov (United States)

    Kahlen, Franz-Josef; Sankaranarayanan, Srikanth; Kar, Aravinda

    1997-09-01

    Subject of this investigation is a one-step rapid machining process to create miniaturized 3D parts, using the original sample material. An experimental setup where metal powder is fed to the laser beam-material interaction region has been built. The powder is melted and forms planar, 2D geometries as the substrate is moved under the laser beam in XY- direction. After completing the geometry in the plane, the substrate is displaced in Z-direction, and a new layer of material is placed on top of the just completed deposit. By continuous repetition of this process, 3D parts wee created. In particular, the impact of the focal spot size of the high power laser beam on the smallest achievable structures was investigated. At a translation speed of 51 mm/s a minimum material thickness of 590 micrometers was achieved. Also, it was shown that a small Z-displacement has a negligible influence on the continuity of the material deposition over this power range. A high power CO2 laser was used as energy source, the material powder under investigation was stainless steel SS304L. Helium was used as shield gas at a flow rate of 15 1/min. The incident CO2 laser beam power was varied between 300 W and 400 W, with the laser beam intensity distribute in a donut mode. The laser beam was focused to a focal diameter of 600 (Mu) m.

  2. 49 CFR 215.203 - Restricted cars.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Restricted cars. 215.203 Section 215.203..., DEPARTMENT OF TRANSPORTATION RAILROAD FREIGHT CAR SAFETY STANDARDS Restricted Equipment § 215.203 Restricted cars. (a) This section restricts the operation of any railroad freight car that is— (1) More than 50...

  3. Step 1: Learn about Diabetes

    Science.gov (United States)

    ... please turn JavaScript on. Feature: Type 2 Diabetes Step 1: Learn About Diabetes Past Issues / Fall 2014 ... the whole family healthy! Here are four key steps to help you control your diabetes and live ...

  4. SPAR-H Step-by-Step Guidance

    Energy Technology Data Exchange (ETDEWEB)

    April M. Whaley; Dana L. Kelly; Ronald L. Boring; William J. Galyean

    2012-06-01

    Step-by-step guidance was developed recently at Idaho National Laboratory for the US Nuclear Regulatory Commission on the use of the Standardized Plant Analysis Risk-Human Reliability Analysis (SPAR-H) method for quantifying Human Failure Events (HFEs). This work was done to address SPAR-H user needs, specifically requests for additional guidance on the proper application of various aspects of the methodology. This paper overviews the steps of the SPAR-H analysis process and highlights some of the most important insights gained during the development of the step-by-step directions. This supplemental guidance for analysts is applicable when plant-specific information is available, and goes beyond the general guidance provided in existing SPAR-H documentation. The steps highlighted in this paper are: Step-1, Categorizing the HFE as Diagnosis and/or Action; Step-2, Rate the Performance Shaping Factors; Step-3, Calculate PSF-Modified HEP; Step-4, Accounting for Dependence, and; Step-5, Minimum Value Cutoff.

  5. The effect of energy restriction on satiation an satiety in obese and lean men

    NARCIS (Netherlands)

    Blom, W.A.M.; Stafleu, A.; Hendriks, H.F.J.

    2004-01-01

    Aims: To investigate how time-blinded obese and lean men compensate for a 3-day energy-restrictive diet. Methods: Subjects were randomly put on a three-day energy-restrictive (ER) (67% energy restriction) and a three-day energy-balanced (EB) diet, with a washout period of one month. Both diets were

  6. Multiple stage miniature stepping motor

    International Nuclear Information System (INIS)

    Niven, W.A.; Shikany, S.D.; Shira, M.L.

    1981-01-01

    A stepping motor comprising a plurality of stages which may be selectively activated to effect stepping movement of the motor, and which are mounted along a common rotor shaft to achieve considerable reduction in motor size and minimum diameter, whereby sequential activation of the stages results in successive rotor steps with direction being determined by the particular activating sequence followed

  7. Arbitrary-step randomly delayed robust filter with application to boost phase tracking

    Science.gov (United States)

    Qin, Wutao; Wang, Xiaogang; Bai, Yuliang; Cui, Naigang

    2018-04-01

    The conventional filters such as extended Kalman filter, unscented Kalman filter and cubature Kalman filter assume that the measurement is available in real-time and the measurement noise is Gaussian white noise. But in practice, both two assumptions are invalid. To solve this problem, a novel algorithm is proposed by taking the following four steps. At first, the measurement model is modified by the Bernoulli random variables to describe the random delay. Then, the expression of predicted measurement and covariance are reformulated, which could get rid of the restriction that the maximum number of delay must be one or two and the assumption that probabilities of Bernoulli random variables taking the value one are equal. Next, the arbitrary-step randomly delayed high-degree cubature Kalman filter is derived based on the 5th-degree spherical-radial rule and the reformulated expressions. Finally, the arbitrary-step randomly delayed high-degree cubature Kalman filter is modified to the arbitrary-step randomly delayed high-degree cubature Huber-based filter based on the Huber technique, which is essentially an M-estimator. Therefore, the proposed filter is not only robust to the randomly delayed measurements, but robust to the glint noise. The application to the boost phase tracking example demonstrate the superiority of the proposed algorithms.

  8. Stepping movement analysis of control rod drive mechanism

    International Nuclear Information System (INIS)

    Xu Yantao; Zu Hongbiao

    2013-01-01

    Background: Control rod drive mechanism (CRDM) is one of the important safety-related equipment for nuclear power plants. Purpose: The operating parameters of stepping movement, including lifting loads, step distance and step velocity, are all critical design targets. Methods: FEA and numerical simulation are used to analyze stepping movement separately. Results: The motion equations of the movable magnet in stepping movement are established by load analysis. Gravitation, magnetic force, fluid resistance and spring force are all in consideration in the load analysis. The operating parameters of stepping movement are given. Conclusions: The results, including time history curves of force, speed and etc, can positively used in the design of CRDM. (authors)

  9. Last Step to Leadership

    Science.gov (United States)

    Finkel, Ed

    2016-01-01

    First-time community college presidents are typically chosen from the senior ranks of two-year colleges' administrations, so they know what the job entails to some extent--at least from a close secondhand perspective. Leaders of community colleges who have taken the reins in the mid-2010s say that a close secondhand view only goes so far in…

  10. First steps in ANAV

    International Nuclear Information System (INIS)

    Rodriguez Rubio, R.

    2010-01-01

    During the initial phase, (General training) the new incorporation follow a training programme during which they spend almost all their time in lessons. The main aim of the Welcome Plan in this phase is to help people understand the organisation of ANAV and their future workplace, as well as to monitor the integration of the candidates in to the training programme. (Author).

  11. Step-to-step spatiotemporal variables and ground reaction forces of intra-individual fastest sprinting in a single session.

    Science.gov (United States)

    Nagahara, Ryu; Mizutani, Mirai; Matsuo, Akifumi; Kanehisa, Hiroaki; Fukunaga, Tetsuo

    2018-06-01

    We aimed to investigate the step-to-step spatiotemporal variables and ground reaction forces during the acceleration phase for characterising intra-individual fastest sprinting within a single session. Step-to-step spatiotemporal variables and ground reaction forces produced by 15 male athletes were measured over a 50-m distance during repeated (three to five) 60-m sprints using a long force platform system. Differences in measured variables between the fastest and slowest trials were examined at each step until the 22nd step using a magnitude-based inferences approach. There were possibly-most likely higher running speed and step frequency (2nd to 22nd steps) and shorter support time (all steps) in the fastest trial than in the slowest trial. Moreover, for the fastest trial there were likely-very likely greater mean propulsive force during the initial four steps and possibly-very likely larger mean net anterior-posterior force until the 17th step. The current results demonstrate that better sprinting performance within a single session is probably achieved by 1) a high step frequency (except the initial step) with short support time at all steps, 2) exerting a greater mean propulsive force during initial acceleration, and 3) producing a greater mean net anterior-posterior force during initial and middle acceleration.

  12. Effects of walking speed on the step-by-step control of step width.

    Science.gov (United States)

    Stimpson, Katy H; Heitkamp, Lauren N; Horne, Joscelyn S; Dean, Jesse C

    2018-02-08

    Young, healthy adults walking at typical preferred speeds use step-by-step adjustments of step width to appropriately redirect their center of mass motion and ensure mediolateral stability. However, it is presently unclear whether this control strategy is retained when walking at the slower speeds preferred by many clinical populations. We investigated whether the typical stabilization strategy is influenced by walking speed. Twelve young, neurologically intact participants walked on a treadmill at a range of prescribed speeds (0.2-1.2 m/s). The mediolateral stabilization strategy was quantified as the proportion of step width variance predicted by the mechanical state of the pelvis throughout a step (calculated as R 2 magnitude from a multiple linear regression). Our ability to accurately predict the upcoming step width increased over the course of a step. The strength of the relationship between step width and pelvis mechanics at the start of a step was reduced at slower speeds. However, these speed-dependent differences largely disappeared by the end of a step, other than at the slowest walking speed (0.2 m/s). These results suggest that mechanics-dependent adjustments in step width are a consistent component of healthy gait across speeds and contexts. However, slower walking speeds may ease this control by allowing mediolateral repositioning of the swing leg to occur later in a step, thus encouraging slower walking among clinical populations with limited sensorimotor control. Published by Elsevier Ltd.

  13. Comparing the efficacy of metronome beeps and stepping stones to adjust gait: steps to follow!

    Science.gov (United States)

    Bank, Paulina J M; Roerdink, Melvyn; Peper, C E

    2011-03-01

    Acoustic metronomes and visual targets have been used in rehabilitation practice to improve pathological gait. In addition, they may be instrumental in evaluating and training instantaneous gait adjustments. The aim of this study was to compare the efficacy of two cue types in inducing gait adjustments, viz. acoustic temporal cues in the form of metronome beeps and visual spatial cues in the form of projected stepping stones. Twenty healthy elderly (aged 63.2 ± 3.6 years) were recruited to walk on an instrumented treadmill at preferred speed and cadence, paced by either metronome beeps or projected stepping stones. Gait adaptations were induced using two manipulations: by perturbing the sequence of cues and by imposing switches from one cueing type to the other. Responses to these manipulations were quantified in terms of step-length and step-time adjustments, the percentage correction achieved over subsequent steps, and the number of steps required to restore the relation between gait and the beeps or stepping stones. The results showed that perturbations in a sequence of stepping stones were overcome faster than those in a sequence of metronome beeps. In switching trials, switching from metronome beeps to stepping stones was achieved faster than vice versa, indicating that gait was influenced more strongly by the stepping stones than the metronome beeps. Together these results revealed that, in healthy elderly, the stepping stones induced gait adjustments more effectively than did the metronome beeps. Potential implications for the use of metronome beeps and stepping stones in gait rehabilitation practice are discussed.

  14. Accelerators Spanish steps

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    In September, the CERN Accelerator School (CAS) held its third General Accelerator Physics Course, the venue this time being Salamanca, the oldest university in Spain. Spain, which rejoined CERN in 1982, now has a vigorous and steadily growing high energy physics community making substantial contributions to physics detector development and successfully involving Spanish industry. However the embryonic accelerator community cannot yet generate an equivalent level of activity, and this important channel for introducing new high technology into industry has yet to be fully exploited

  15. Control Software for Piezo Stepping Actuators

    Science.gov (United States)

    Shields, Joel F.

    2013-01-01

    A control system has been developed for the Space Interferometer Mission (SIM) piezo stepping actuator. Piezo stepping actuators are novel because they offer extreme dynamic range (centimeter stroke with nanometer resolution) with power, thermal, mass, and volume advantages over existing motorized actuation technology. These advantages come with the added benefit of greatly reduced complexity in the support electronics. The piezo stepping actuator consists of three fully redundant sets of piezoelectric transducers (PZTs), two sets of brake PZTs, and one set of extension PZTs. These PZTs are used to grasp and move a runner attached to the optic to be moved. By proper cycling of the two brake and extension PZTs, both forward and backward moves of the runner can be achieved. Each brake can be configured for either a power-on or power-off state. For SIM, the brakes and gate of the mechanism are configured in such a manner that, at the end of the step, the actuator is in a parked or power-off state. The control software uses asynchronous sampling of an optical encoder to monitor the position of the runner. These samples are timed to coincide with the end of the previous move, which may consist of a variable number of steps. This sampling technique linearizes the device by avoiding input saturation of the actuator and makes latencies of the plant vanish. The software also estimates, in real time, the scale factor of the device and a disturbance caused by cycling of the brakes. These estimates are used to actively cancel the brake disturbance. The control system also includes feedback and feedforward elements that regulate the position of the runner to a given reference position. Convergence time for smalland medium-sized reference positions (less than 200 microns) to within 10 nanometers can be achieved in under 10 seconds. Convergence times for large moves (greater than 1 millimeter) are limited by the step rate.

  16. [First steps in neuronavigation].

    Science.gov (United States)

    Castilla, J M; Martín, V; Fernández-Arconada, O; Delgado, P; Rodríguez-Salazar, A

    2003-10-01

    We try to evaluate the introduction of a neuronavigation system widely used in a neurosurgical department. We analyze the surgical procedures performed since the introduction of a neuronavigator in our hospital, the advantages and the problems related with its use. From 21/12/00 to 31/12/01, 64 cranial and 5 spinal procedures were performed in our centre with the aid of the BrainLAB neuronavigation system. They were 19.37% of the elective surgeries: 45.7% of cranial and 2.8% of spinal procedures. The accuracy of registration was 1.6 mm; the number of trials for registration was 2.8 on average, although in 3 cases it was not possible; there were disarrangements during 9 surgical procedures (two of them after the lesions were reached). Magnetic resonance imaging (MRI) was used in 54 instances, computerized tomography (CT) in 5, fluoroscopy (Rx) in 1, CT plus MRI in 8, CT plus Rx in 1. Since Z-Touch localization system and software was available, it was used exclusively, disregarding the use of external fiducials. In our experience, neuronavigation needs extra time, but it helps in the election of the best position for the surgical approach, reduces the time required for scalp incision and craniotomy planning, and is useful for the opening of the dura and the corticectomy. As the operation proceeds, we found it less truhstworthy and necessary. The Z-touch system frees the imaging from the surgery. Its use in spinal operation is scarce and with limited results in our practice. We found the neuronavigation useful, and we employ it on a regular basis in every cranial procedure whenever it is possible.

  17. HTSC-Josephson step contacts

    International Nuclear Information System (INIS)

    Herrmann, K.

    1994-03-01

    In this work the properties of josephson step contacts are investigated. After a short introduction into Josephson step contacts the structure, properties and the Josphson contacts of YBa 2 Cu 3 O 7-x high-T c superconductors is presented. The fabrication of HTSC step contacts and the microstructure is discussed. The electric properties of these contacts are measured together with the Josephson emission and the magnetic field dependence. The temperature dependence of the stationary transport properties is given. (WL)

  18. The NIST Step Class Library (Step Into the Future)

    Science.gov (United States)

    1990-09-01

    Figure 6. Excerpt from a STEP exclange file based on the Geometry model 1be NIST STEP Class Libary Page 13 An issue of concern in this...Scheifler, R., Gettys, J., and Newman, P., X Window System: C Library and Protocol Reference. Digital Press, Bedford, Mass, 1988. [Schenck90] Schenck, D

  19. Step-by-Step Visual Manuals: Design and Development

    Science.gov (United States)

    Urata, Toshiyuki

    2004-01-01

    The types of handouts and manuals that are used in technology training vary. Some describe procedures in a narrative way without graphics; some employ step-by-step instructions with screen captures. According to Thirlway (1994), a training manual should be like a tutor that permits a student to learn at his own pace and gives him confidence for…

  20. The bounded proof property via step algebras and step frames

    NARCIS (Netherlands)

    Bezhanishvili, N.; Ghilardi, Silvio

    2013-01-01

    We develop a semantic criterion for a specific rule-based calculus Ax axiomatizing a given logic L to have the so-called bounded proof property. This property is a kind of an analytic subformula property limiting the proof search space. Our main tools are one-step frames and one-step algebras. These

  1. Leading Change Step-by-Step: Tactics, Tools, and Tales

    Science.gov (United States)

    Spiro, Jody

    2010-01-01

    "Leading Change Step-by-Step" offers a comprehensive and tactical guide for change leaders. Spiro's approach has been field-tested for more than a decade and proven effective in a wide variety of public sector organizations including K-12 schools, universities, international agencies and non-profits. The book is filled with proven tactics for…

  2. Rurality study of restricted areas

    Directory of Open Access Journals (Sweden)

    Sergio Rivaroli

    2011-02-01

    Full Text Available Two main perspectives of investigation emerge from the study of a territory’s rurality: a geographical approach and a sociological approach. The research examines the sub-regional study case of ‘Nuovo circondario imolese’. The analysis shows that the combination of traditional institutional criteria with detailed informations about the territory, generates more accurate results which determine a better comprehension of the characteristics of restricted areas’ rurality. Over the period 1991-2001, the study highlights an increase in rural areas. This result could be interpreted as an effect of urban sprawl’s intensification, that increases the competition between non-farm residences and agricultural activities.

  3. Continuous versus step-by-step scanning mode of a novel 3D scanner for CyberKnife measurements

    International Nuclear Information System (INIS)

    Al Kafi, M Abdullah; Mwidu, Umar; Moftah, Belal

    2015-01-01

    The purpose of the study is to investigate the continuous versus step-by-step scanning mode of a commercial circular 3D scanner for commissioning measurements of a robotic stereotactic radiosurgery system. The 3D scanner was used for profile measurements in step-by-step and continuous modes with the intent of comparing the two scanning modes for consistency. The profile measurements of in-plane, cross-plane, 15 degree, and 105 degree were performed for both fixed cones and Iris collimators at depth of maximum dose and at 10 cm depth. For CyberKnife field size, penumbra, flatness and symmetry analysis, it was observed that the measurements with continuous mode, which can be up to 6 times faster than step-by-step mode, are comparable and produce scans nearly identical to step-by-step mode. When compared with centered step-by-step mode data, a fully processed continuous mode data gives rise to maximum of 0.50% and 0.60% symmetry and flatness difference respectfully for all the fixed cones and Iris collimators studied. - Highlights: • D scanner for CyberKnife beam data measurements. • Beam data analysis for continuous and step-by-step scan modes. • Faster continuous scanning data are comparable to step-by-step mode scan data.

  4. The restricted stochastic user equilibrium with threshold model: Large-scale application and parameter testing

    DEFF Research Database (Denmark)

    Rasmussen, Thomas Kjær; Nielsen, Otto Anker; Watling, David P.

    2017-01-01

    Equilibrium model (DUE), by combining the strengths of the Boundedly Rational User Equilibrium model and the Restricted Stochastic User Equilibrium model (RSUE). Thereby, the RSUET model reaches an equilibrated solution in which the flow is distributed according to Random Utility Theory among a consistently...... model improves the behavioural realism, especially for high congestion cases. Also, fast and well-behaved convergence to equilibrated solutions among non-universal choice sets is observed across different congestion levels, choice model scale parameters, and algorithm step sizes. Clearly, the results...... highlight that the RSUET outperforms the MNP SUE in terms of convergence, calculation time and behavioural realism. The choice set composition is validated by using 16,618 observed route choices collected by GPS devices in the same network and observing their reproduction within the equilibrated choice sets...

  5. Power of the on-the-job training under a efficient and personalized method: a profitable solution for restrictive time; A potencia do treinamento no local do trabalho sob um metodo eficaz e personalizado: uma solucao rentavel em tempos restritivos

    Energy Technology Data Exchange (ETDEWEB)

    Castillero, Jose Antonio Moreno; Melo Junior, Hilter Bezerra Bandeira de [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    1998-07-01

    On- the- job training of Refineries operation team is showed like feasible option to face the present times difficulties. This option is efficient only if it's allied to the method showed based in intensive dialogue between interlocutor and trainees, looking for technical-human valorization and individual prestige in group. The method applied is universal. Results from a PETROBRAS Refinery application of method are showed, about Catalytic Cracking Thermal Balance and others Fundamentals. Is showed a conceptual thinking model applied for the specific affair, for intellectual comprehensive of perturbations on industrial process equilibrium. (author)

  6. Parenting and restrictions in childhood epilepsy

    NARCIS (Netherlands)

    Rodenburg, R.; Meijer, A.M.; Scherphof, C.; Carpay, J.A.; Augustijn, P.; Aldenkamp, A.P.; Deković, M.

    2013-01-01

    Purpose: From the overprotection literature, the predictive and interactional (moderation) effects of controlling and indulgent parenting on restrictions in children with epilepsy were examined. Methods: Parents of 73 children with epilepsy completed questionnaires on parenting, restrictions, and

  7. Microsoft® Visual Basic® 2010 Step by Step

    CERN Document Server

    Halvorson, Michael

    2010-01-01

    Your hands-on, step-by-step guide to learning Visual Basic® 2010. Teach yourself the essential tools and techniques for Visual Basic® 2010-one step at a time. No matter what your skill level, you'll find the practical guidance and examples you need to start building professional applications for Windows® and the Web. Discover how to: Work in the Microsoft® Visual Studio® 2010 Integrated Development Environment (IDE)Master essential techniques-from managing data and variables to using inheritance and dialog boxesCreate professional-looking UIs; add visual effects and print supportBuild com

  8. 49 CFR 383.95 - Restrictions.

    Science.gov (United States)

    2010-10-01

    ... the skills test and the restriction, air brakes shall include any braking system operating fully or...; REQUIREMENTS AND PENALTIES Vehicle Groups and Endorsements § 383.95 Restrictions. (a) Air brake restrictions... skills test in a vehicle not equipped with air brakes, the State must indicate on the CDL, if issued...

  9. 9 CFR 92.3 - Movement restrictions.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Movement restrictions. 92.3 Section 92... ANIMAL PRODUCTS: PROCEDURES FOR REQUESTING RECOGNITION OF REGIONS § 92.3 Movement restrictions. Whenever... exist and the EC imposes prohibitions or other restrictions on the movement of animals or animal...

  10. 21 CFR 203.20 - Sales restrictions.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Sales restrictions. 203.20 Section 203.20 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL PRESCRIPTION DRUG MARKETING Sales Restrictions § 203.20 Sales restrictions. Except as provided in § 203.22 or...

  11. A small step for mankind

    NARCIS (Netherlands)

    Huizing, C.; Koymans, R.L.C.; Kuiper, R.; Dams, D.; Hannemann, U.; Steffen, M.

    2010-01-01

    For many programming languages, the only formal semantics published is an SOS big-step semantics. Such a semantics is not suited for investigations that observe intermediate states, such as invariant techniques. In this paper, a construction is proposed that generates automatically a small-step SOS

  12. One-step lowrank wave extrapolation

    KAUST Repository

    Sindi, Ghada Atif

    2014-01-01

    Wavefield extrapolation is at the heart of modeling, imaging, and Full waveform inversion. Spectral methods gained well deserved attention due to their dispersion free solutions and their natural handling of anisotropic media. We propose a scheme a modified one-step lowrank wave extrapolation using Shanks transform in isotropic, and anisotropic media. Specifically, we utilize a velocity gradient term to add to the accuracy of the phase approximation function in the spectral implementation. With the higher accuracy, we can utilize larger time steps and make the extrapolation more efficient. Applications to models with strong inhomogeneity and considerable anisotropy demonstrates the utility of the approach.

  13. Cardiorespiratory effects of inelastic chest wall restriction.

    Science.gov (United States)

    Miller, Jordan D; Beck, Kenneth C; Joyner, Michael J; Brice, A Glenn; Johnson, Bruce D

    2002-06-01

    We examined the effects of chest wall restriction (CWR) on cardiorespiratory function at rest and during exercise in healthy subjects in an attempt to approximate the cardiorespiratory interactions observed in clinical conditions that result in restrictive lung and/or chest wall changes and a reduced intrathoracic space. Canvas straps were applied around the thorax and abdomen so that vital capacity was reduced by >35%. Data were acquired at rest and during cycle ergometry at 25 and 45% of peak workloads. CWR elicited significant increases in the flow-resistive work performed on the lung (160%) and the gastric pressure-time integral (>400%) at the higher workload, but it resulted in a decrease in the elastic work performed on the lung (56%) compared with control conditions. With CWR, heart rate increased and stroke volume (SV) fell, resulting in >10% fall in cardiac output at rest and during exercise at matched workloads (P < 0.05). Blood pressure and catecholamines were significantly elevated during CWR exercise conditions (P < 0.05). We conclude that CWR significantly impairs SV during exercise and that a compensatory increase in heart rate does not prevent a significant reduction in cardiac output. O(2) consumption appears to be maintained via increased extraction and a redistribution of blood flow via sympathetic activation.

  14. Restricted mouth opening and its definitive management: A literature review

    Directory of Open Access Journals (Sweden)

    Bhushan Kumar

    2018-01-01

    Full Text Available Purpose: This review was intended to discuss the various possible modifications suggested in the literature for prosthetic steps and surgical corrective procedures in nonresponding or complicated cases during rehabilitation of patients with restricted mouth opening. Material and Methods: Medline, PubMed, and Google were searched electronically for articles using keywords: microstomia and treatment options for restricted mouth opening. The various articles on prosthodontic rehabilitation in microstomia were segregated. From these, various modifications in the prosthetic steps were reviewed. Results: Oral hygiene maintenance is difficult for patient either due to limited access or due to associated lack of manual dexterity, so dental decay and periodontal problems are more extensive in such patients; hence, tooth loss is a common finding. All prosthetic procedures require wide mouth opening to carry out various steps, starting from tray placement during impression making to the final prosthesis insertion, especially removable prosthesis. Various prosthetic modifications given by authors are included in this review for each step in prosthodontic management. A total of eight stock tray designs, 12 custom tray designs, and 17 removable prosthesis designs are discussed along with fixed (either tooth-supported or implant-supported and maxillofacial prosthesis. However, some patients require surgical intervention also for the correction of microstomia either for function or for esthetic purpose before prosthetic rehabilitation and are also enumerated here. Conclusion: Among all prosthetic restorative options, removable prosthesis is most difficult for dentist to fabricate as conventional methods are either very difficult or impossible to apply. To get a more accurate final prosthesis, we need to modify these steps according to the existing case. Several modifications available are discussed here which can help while managing these patients.

  15. Restricted mouth opening and its definitive management: A literature review.

    Science.gov (United States)

    Kumar, Bhushan; Fernandes, Aquaviva; Sandhu, Prabhdeep Kaur

    2018-01-01

    This review was intended to discuss the various possible modifications suggested in the literature for prosthetic steps and surgical corrective procedures in nonresponding or complicated cases during rehabilitation of patients with restricted mouth opening. Medline, PubMed, and Google were searched electronically for articles using keywords: microstomia and treatment options for restricted mouth opening. The various articles on prosthodontic rehabilitation in microstomia were segregated. From these, various modifications in the prosthetic steps were reviewed. Oral hygiene maintenance is difficult for patient either due to limited access or due to associated lack of manual dexterity, so dental decay and periodontal problems are more extensive in such patients; hence, tooth loss is a common finding. All prosthetic procedures require wide mouth opening to carry out various steps, starting from tray placement during impression making to the final prosthesis insertion, especially removable prosthesis. Various prosthetic modifications given by authors are included in this review for each step in prosthodontic management. A total of eight stock tray designs, 12 custom tray designs, and 17 removable prosthesis designs are discussed along with fixed (either tooth-supported or implant-supported) and maxillofacial prosthesis. However, some patients require surgical intervention also for the correction of microstomia either for function or for esthetic purpose before prosthetic rehabilitation and are also enumerated here. Among all prosthetic restorative options, removable prosthesis is most difficult for dentist to fabricate as conventional methods are either very difficult or impossible to apply. To get a more accurate final prosthesis, we need to modify these steps according to the existing case. Several modifications available are discussed here which can help while managing these patients.

  16. When a Step Is Not a Step! Specificity Analysis of Five Physical Activity Monitors.

    Directory of Open Access Journals (Sweden)

    Sandra O'Connell

    Full Text Available Physical activity is an essential aspect of a healthy lifestyle for both physical and mental health states. As step count is one of the most utilized measures for quantifying physical activity it is important that activity-monitoring devices be both sensitive and specific in recording actual steps taken and disregard non-stepping body movements. The objective of this study was to assess the specificity of five activity monitors during a variety of prescribed non-stepping activities.Participants wore five activity monitors simultaneously for a variety of prescribed activities including deskwork, taking an elevator, taking a bus journey, automobile driving, washing and drying dishes; functional reaching task; indoor cycling; outdoor cycling; and indoor rowing. Each task was carried out for either a specific duration of time or over a specific distance. Activity monitors tested were the ActivPAL micro™, NL-2000™ pedometer, Withings Smart Activity Monitor Tracker (Pulse O2™, Fitbit One™ and Jawbone UP™. Participants were video-recorded while carrying out the prescribed activities and the false positive step count registered on each activity monitor was obtained and compared to the video.All activity monitors registered a significant number of false positive steps per minute during one or more of the prescribed activities. The Withings™ activity performed best, registering a significant number of false positive steps per minute during the outdoor cycling activity only (P = 0.025. The Jawbone™ registered a significant number of false positive steps during the functional reaching task and while washing and drying dishes, which involved arm and hand movement (P < 0.01 for both. The ActivPAL™ registered a significant number of false positive steps during the cycling exercises (P < 0.001 for both.As a number of false positive steps were registered on the activity monitors during the non-stepping activities, the authors conclude that non-stepping

  17. When a Step Is Not a Step! Specificity Analysis of Five Physical Activity Monitors.

    Science.gov (United States)

    O'Connell, Sandra; ÓLaighin, Gearóid; Quinlan, Leo R

    2017-01-01

    Physical activity is an essential aspect of a healthy lifestyle for both physical and mental health states. As step count is one of the most utilized measures for quantifying physical activity it is important that activity-monitoring devices be both sensitive and specific in recording actual steps taken and disregard non-stepping body movements. The objective of this study was to assess the specificity of five activity monitors during a variety of prescribed non-stepping activities. Participants wore five activity monitors simultaneously for a variety of prescribed activities including deskwork, taking an elevator, taking a bus journey, automobile driving, washing and drying dishes; functional reaching task; indoor cycling; outdoor cycling; and indoor rowing. Each task was carried out for either a specific duration of time or over a specific distance. Activity monitors tested were the ActivPAL micro™, NL-2000™ pedometer, Withings Smart Activity Monitor Tracker (Pulse O2)™, Fitbit One™ and Jawbone UP™. Participants were video-recorded while carrying out the prescribed activities and the false positive step count registered on each activity monitor was obtained and compared to the video. All activity monitors registered a significant number of false positive steps per minute during one or more of the prescribed activities. The Withings™ activity performed best, registering a significant number of false positive steps per minute during the outdoor cycling activity only (P = 0.025). The Jawbone™ registered a significant number of false positive steps during the functional reaching task and while washing and drying dishes, which involved arm and hand movement (P positive steps during the cycling exercises (P positive steps were registered on the activity monitors during the non-stepping activities, the authors conclude that non-stepping physical activities can result in the false detection of steps. This can negatively affect the quantification of physical

  18. Growth assessment in diagnosis of Fetal Growth Restriction. Review.

    Science.gov (United States)

    Albu, A R; Horhoianu, I A; Dumitrascu, M C; Horhoianu, V

    2014-06-15

    The assessment of fetal growth represents a fundamental step towards the identification of the true growth restricted fetus that is associated to important perinatal morbidity and mortality. The possible ways of detecting abnormal fetal growth are taken into consideration in this review and their strong and weak points are discussed. An important debate still remains about how to discriminate between the physiologically small fetus that does not require special surveillance and the truly growth restricted fetus who is predisposed to perinatal complications, even if its parameters are above the cut-off limits established. In this article, we present the clinical tools of fetal growth assessment: Symphyseal-Fundal Height (SFH) measurement, the fetal ultrasound parameters widely taken into consideration when discussing fetal growth: Abdominal Circumference (AC) and Estimated Fetal Weight (EFW); several types of growth charts and their characteristics: populational growth charts, standard growth charts, individualized growth charts, customized growth charts and growth trajectories.

  19. Measuring Restriction Sizes Using Diffusion Weighted Magnetic Resonance Imaging: A Review

    Directory of Open Access Journals (Sweden)

    Melanie Martin

    2013-01-01

    Full Text Available This article reviews a new concept in magnetic resonance as applied to cellular and biological systems. Diffusion weighted magnetic resonance imaging can be used to infer information about restriction sizes of samples being measured. The measurements rely on the apparent diffusion coefficient changing with diffusion times as measurements move from restricted to free diffusion regimes. Pulsed gradient spin echo (PGSE measurements are limited in the ability to shorten diffusion times and thus are limited in restriction sizes which can be probed. Oscillating gradient spin echo (OGSE measurements could provide shorter diffusion times so smaller restriction sizes could be probed.

  20. One False Step: "Detroit," "Step" and Movies of Rising and Falling

    Science.gov (United States)

    Beck, Bernard

    2018-01-01

    "Detroit" and "Step" are two recent movies in the context of urban riots in protest of police brutality. They refer to time periods separated by half a century, but there are common themes in the two that seem appropriate to both times. The movies are not primarily concerned with the riot events, but the riot is a major…

  1. Restricted Predicates for Hypothetical Datalog

    Directory of Open Access Journals (Sweden)

    Fernando Sáenz-Pérez

    2015-12-01

    Full Text Available Hypothetical Datalog is based on an intuitionistic semantics rather than on a classical logic semantics, and embedded implications are allowed in rule bodies. While the usual implication (i.e., the neck of a Horn clause stands for inferring facts, an embedded implication plays the role of assuming its premise for deriving its consequence. A former work introduced both a formal framework and a goal-oriented tabled implementation, allowing negation in rule bodies. While in that work positive assumptions for both facts and rules can occur in the premise, negative assumptions are not allowed. In this work, we cover this subject by introducing a new concept: a restricted predicate, which allows negative assumptions by pruning the usual semantics of a predicate. This new setting has been implemented in the deductive system DES.

  2. Microprocessor controller for stepping motors

    International Nuclear Information System (INIS)

    Strait, B.G.; Thuot, M.E.

    1977-01-01

    A new concept for digital computer control of multiple stepping motors which operate in a severe electromagnetic pulse environment is presented. The motors position mirrors in the beam-alignment system of a 100-kJ CO 2 laser. An asynchronous communications channel of a computer is used to send coded messages, containing the motor address and stepping-command information, to the stepping-motor controller in a bit serial format over a fiber-optics communications link. The addressed controller responds by transmitting to the computer its address and other motor information, thus confirming the received message. Each controller is capable of controlling three stepping motors. The controller contains the fiber-optics interface, a microprocessor, and the stepping-motor driven circuits. The microprocessor program, which resides in an EPROM, decodes the received messages, transmits responses, performs the stepping-motor sequence logic, maintains motor-position information, and monitors the motor's reference switch. For multiple stepping-motor application, the controllers are connected in a daisy chain providing control of many motors from one asynchronous communications channel of the computer

  3. Cost-effectiveness of a modified two-step algorithm using a combined glutamate dehydrogenase/toxin enzyme immunoassay and real-time PCR for the diagnosis of Clostridium difficile infection.

    Science.gov (United States)

    Vasoo, Shawn; Stevens, Jane; Portillo, Lena; Barza, Ruby; Schejbal, Debra; Wu, May May; Chancey, Christina; Singh, Kamaljit

    2014-02-01

    The analytical performance and cost-effectiveness of the Wampole Toxin A/B EIA, the C. Diff. Quik Chek Complete (CdQCC) (a combined glutamate dehydrogenase antigen/toxin enzyme immunoassay), two RT-PCR assays (Progastro Cd and BD GeneOhm) and a modified two-step algorithm using the CdQCC reflexed to RT-PCR for indeterminate results were compared. The sensitivity of the Wampole Toxin A/B EIA, CdQCC (GDH antigen), BD GeneOhm and Progastro Cd RT-PCR were 85.4%, 95.8%, 100% and 93.8%, respectively. The algorithm provided rapid results for 86% of specimens and the remaining indeterminate results were resolved by RT-PCR, offering the best balance of sensitivity and cost savings per test (algorithm ∼US$13.50/test versus upfront RT-PCR ∼US$26.00/test). Copyright © 2012. Published by Elsevier B.V.

  4. A Traffic Restriction Scheme for Enhancing Carpooling

    Directory of Open Access Journals (Sweden)

    Dong Ding

    2017-01-01

    Full Text Available For the purpose of alleviating traffic congestion, this paper proposes a scheme to encourage travelers to carpool by traffic restriction. By a variational inequity we describe travelers’ mode (solo driving and carpooling and route choice under user equilibrium principle in the context of fixed demand and detect the performance of a simple network with various restriction links, restriction proportions, and carpooling costs. Then the optimal traffic restriction scheme aiming at minimal total travel cost is designed through a bilevel program and applied to a Sioux Fall network example with genetic algorithm. According to various requirements, optimal restriction regions and proportions for restricted automobiles are captured. From the results it is found that traffic restriction scheme is possible to enhance carpooling and alleviate congestion. However, higher carpooling demand is not always helpful to the whole network. The topology of network, OD demand, and carpooling cost are included in the factors influencing the performance of the traffic system.

  5. Two-Step Oxidation of Refractory Gold Concentrates with Different Microbial Communities.

    Science.gov (United States)

    Wang, Guo-Hua; Xie, Jian-Ping; Li, Shou-Peng; Guo, Yu-Jie; Pan, Ying; Wu, Haiyan; Liu, Xin-Xing

    2016-11-28

    Bio-oxidation is an effective technology for treatment of refractory gold concentrates. However, the unsatisfactory oxidation rate and long residence time, which cause a lower cyanide leaching rate and gold recovery, are key factors that restrict the application of traditional bio-oxidation technology. In this study, the oxidation rate of refractory gold concentrates and the adaption of microorganisms were analyzed to evaluate a newly developed two-step pretreatment process, which includes a high temperature chemical oxidation step and a subsequent bio-oxidation step. The oxidation rate and recovery rate of gold were improved significantly after the two-step process. The results showed that the highest oxidation rate of sulfide sulfur could reach to 99.01 % with an extreme thermophile microbial community when the pulp density was 5%. Accordingly, the recovery rate of gold was elevated to 92.51%. Meanwhile, the results revealed that moderate thermophiles performed better than acidophilic mesophiles and extreme thermophiles, whose oxidation rates declined drastically when the pulp density was increased to 10% and 15%. The oxidation rates of sulfide sulfur with moderate thermophiles were 93.94% and 65.73% when the pulp density was increased to 10% and 15%, respectively. All these results indicated that the two-step pretreatment increased the oxidation rate of refractory gold concentrates and is a potential technology to pretreat the refractory sample. Meanwhile, owing to the sensitivity of the microbial community under different pulp density levels, the optimization of microbial community in bio-oxidation is necessary in industry.

  6. Adsorption-induced step formation

    DEFF Research Database (Denmark)

    Thostrup, P.; Christoffersen, Ebbe; Lorensen, Henrik Qvist

    2001-01-01

    Through an interplay between density functional calculations, Monte Carlo simulations and scanning tunneling microscopy experiments, we show that an intermediate coverage of CO on the Pt(110) surface gives rise to a new rough equilibrium structure with more than 50% step atoms. CO is shown to bind...... so strongly to low-coordinated Pt atoms that it can break Pt-Pt bonds and spontaneously form steps on the surface. It is argued that adsorption-induced step formation may be a general effect, in particular at high gas pressures and temperatures....

  7. Step sites in syngas catalysis

    DEFF Research Database (Denmark)

    Rostrup-Nielsen, J.; Nørskov, Jens Kehlet

    2006-01-01

    Step sites play an important role in many catalytic reactions. This paper reviews recent results on metal catalysts for syngas reactions with emphasis on steam reforming. Modern characterization techniques (STEM, HREM...) and theoretical calculations (DFT) has allowed a more quantitative explanat......Step sites play an important role in many catalytic reactions. This paper reviews recent results on metal catalysts for syngas reactions with emphasis on steam reforming. Modern characterization techniques (STEM, HREM...) and theoretical calculations (DFT) has allowed a more quantitative...... explanation of the impact of step sites on catalyst activity and side reactions such as carbon formation. This leads to a discussion of principles for catalyst promotion....

  8. Performance of an attention-demanding task during treadmill walking shifts the noise qualities of step-to-step variation in step width.

    Science.gov (United States)

    Grabiner, Mark D; Marone, Jane R; Wyatt, Marilynn; Sessoms, Pinata; Kaufman, Kenton R

    2018-06-01

    The fractal scaling evident in the step-to-step fluctuations of stepping-related time series reflects, to some degree, neuromotor noise. The primary purpose of this study was to determine the extent to which the fractal scaling of step width, step width and step width variability are affected by performance of an attention-demanding task. We hypothesized that the attention-demanding task would shift the structure of the step width time series toward white, uncorrelated noise. Subjects performed two 10-min treadmill walking trials, a control trial of undisturbed walking and a trial during which they performed a mental arithmetic/texting task. Motion capture data was converted to step width time series, the fractal scaling of which were determined from their power spectra. Fractal scaling decreased by 22% during the texting condition (p Step width and step width variability increased 19% and five percent, respectively (p step width fractal scaling. The change of the fractal scaling of step width is consistent with increased cognitive demand and suggests a transition in the characteristics of the signal noise. This may reflect an important advance toward the understanding of the manner in which neuromotor noise contributes to some types of falls. However, further investigation of the repeatability of the results, the sensitivity of the results to progressive increases in cognitive load imposed by attention-demanding tasks, and the extent to which the results can be generalized to the gait of older adults seems warranted. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. CEXE INCEXE, 1 Group 3-D Time-Dependent Xe Oscillations in X-Y-Z Geometry with Feedback

    International Nuclear Information System (INIS)

    Kern, R.; Pacino, S.

    1973-01-01

    1 - Description of problem or function: CEXE solves the three- dimensional xyz time-dependent xenon spatial oscillation problem using a modified one energy group theory and a nodal representation. 2 - Method of solution: CEXE solves for the spatial neutron source distribution with coupled Doppler and moderator temperature feedbacks. The time dependence of the iodine and xenon concentrations are based on the assumption of constant power during each time-step interval. 3 - Restrictions on the complexity of the problem: Maximum reactor core size representation is restricted to a nodal configuration of 19 x 19 x 10 in the x, y, z directions, respectively

  10. Restricted Interval Valued Neutrosophic Sets and Restricted Interval Valued Neutrosophic Topological Spaces

    Directory of Open Access Journals (Sweden)

    Anjan Mukherjee

    2016-08-01

    Full Text Available In this paper we introduce the concept of restricted interval valued neutrosophic sets (RIVNS in short. Some basic operations and properties of RIVNS are discussed. The concept of restricted interval valued neutrosophic topology is also introduced together with restricted interval valued neutrosophic finer and restricted interval valued neutrosophic coarser topology. We also define restricted interval valued neutrosophic interior and closer of a restricted interval valued neutrosophic set. Some theorems and examples are cites. Restricted interval valued neutrosophic subspace topology is also studied.

  11. Time-discrete higher order ALE formulations: a priori error analysis

    KAUST Repository

    Bonito, Andrea

    2013-03-16

    We derive optimal a priori error estimates for discontinuous Galerkin (dG) time discrete schemes of any order applied to an advection-diffusion model defined on moving domains and written in the Arbitrary Lagrangian Eulerian (ALE) framework. Our estimates hold without any restrictions on the time steps for dG with exact integration or Reynolds\\' quadrature. They involve a mild restriction on the time steps for the practical Runge-Kutta-Radau methods of any order. The key ingredients are the stability results shown earlier in Bonito et al. (Time-discrete higher order ALE formulations: stability, 2013) along with a novel ALE projection. Numerical experiments illustrate and complement our theoretical results. © 2013 Springer-Verlag Berlin Heidelberg.

  12. Restricted fish feeding reduces cod otolith opacity

    DEFF Research Database (Denmark)

    Høie, H.; Folkvord, A.; Mosegaard, Henrik

    2008-01-01

    The purpose of this work was to examine the effect of reduced feeding and constant temperature on cod otolith opacity. Three groups of juvenile cod were given restricted food rations at different times for 4 months, resulting in depressed somatic growth. Otolith opacity was measured on pictures...... in otolith opacity were found between individual fish both within groups and between groups. In two of the three groups significantly more translucent otolith material was deposited in response to reduced feeding. Our results show that variations in feeding and hence fish growth resulted in variation...... in otolith opacity, but the effect was minor compared to that of variations in ambient temperature. The combined influence of these effects, which both act on fish metabolism, are most likely controlling the seasonal opacity changes observed in wild fish. Our results help explain the variations seen in fish...

  13. The primary steps of photosynthesis

    International Nuclear Information System (INIS)

    Fleming, G.R.; Van Grondelle, R.

    1996-01-01

    The two important initial steps of photosynthesis-electron transfer and energy transfer occur with great speed and efficiency. New techniques in laser optics and genetic engineering age helping us to understand why. (author). 24 refs. 8 figs

  14. 7 Steps to Aging Well

    Science.gov (United States)

    ... Issue Past Issues Special Section 7 Steps to Aging Well Past Issues / Winter 2007 Table of Contents ... Exercise: A Guide from the National Institute on Aging is a publication from NIA that has strength, ...

  15. The resurgence of selective contracting restrictions.

    Science.gov (United States)

    Marsteller, J A; Bovbjerg, R R; Nichols, L M; Verrilli, D K

    1997-10-01

    As managed care has spread, so has legislation to force plans to contract with any willing provider (AWP) and give patients freedom of choice (FOC). Managed care organizations' selective networks and provider integration reduce patient access to providers, along with provider access to paying patients, so many providers have lobbied for AWP-FOC laws. In opposition are managed care organizations (MCOs), which want full freedom to contract selectively to control prices and utilization. This article comprehensively describes laws in all fifty-one jurisdictions, classifies their relative strength, and assesses the implications of the laws. Most are relatively weak forms and all are limited in application by ERISA and the federal HMO Act. The article also uses an associative multivariate analysis to relate the selective contracting environments to HMO penetration rates, rural population, physician density, and other variables. States with weak laws also have higher HMO penetration and higher physician density, but smaller rural populations. We conclude that the strongest laws overly restrict the management of care, to the likely detriment of cost control. But where market power is rapidly concentrating, not restricting selective contracting could diminish long-term competition and patient access to care. In the face of uncertainty about the impact of these laws, an intermediate approach may be better than all or nothing. States should consider mandating that plans offer point-of-service options, for a separate premium. This option expands patient choice of plans at the time of enrollment and of providers at the time of care, yet maintains plans' ability to control core providers.

  16. A theory of the stepped leader in lightning

    International Nuclear Information System (INIS)

    Lowke, J.J.

    1999-01-01

    There is no generally accepted explanation of the stepped leader behaviour in terms of basic physical processes. Existing theories generally involve significant gas heating within the stepped leader. In the present paper, the stepped nature of the leader is proposed to arise due to a combination of two physical phenomena. Electron transport is dominant over ion transport, during the luminous step stage, because electron mobilities are about 100 times larger than ion mobilities, and the streamer front velocity is determined by electron ionization effects. During the dark time between steps, there are only ions and charge transport is very much slower. The second effect leading to stepped behaviour arises because the electric field required for electric breakdown in air prior to a discharge is ∼30kV/cm, and is very much higher than the electric field of 5kV/cm that is required to sustain a glow discharge in air. During the luminous step stage, electrons tend to produce space charges to make a uniform field in the streamer of ∼5kV/cm. During the dark time between steps, there are no electrons but only ions. Time is required for ion drift to produce a space charge sheath of negative ions at the head of the streamer to produce a field of ∼30kV/cm sufficient for electron ionization to produce a new luminous step

  17. Do lightning positive leaders really "step"?

    Science.gov (United States)

    Petersen, D.

    2015-12-01

    It has been known for some time that positive leaders exhibit impulsive charge motion and optical emissions as they extend. However, laboratory and field observations have not produced any evidence of a process analogous to the space leader mechanism of negative leader extension. Instead, observations have suggested that the positive leader tip undergoes a continuous to intermittent series of corona streamer bursts, each burst resulting in a small forward extension of the positive leader channel. Traditionally, it has been held that lightning positive leaders extend in a continuous or quasi-continuous fashion. Lately, however, many have become concerned that this position is incongruous with observations of impulsive activity during lightning positive leader extension. It is increasingly suggested that this impulsive activity is evidence that positive leaders also undergo "stepping". There are two issues that must be addressed. The first issue concerns whether or not the physical processes underlying impulsive extension in negative and positive leaders are distinct. We argue that these processes are in fact physically distinct, and offer new high-speed video evidence to support this position. The second issue regards the proper use of the term "step" as an identifier for the impulsive forward extension of a leader. Traditional use of this term has been applied only to negative leaders, due primarily to their stronger impulsive charge motions and photographic evidence of clearly discontinuous forward progression of the luminous channel. Recently, due to the increasing understanding of the distinct "space leader" process of negative leader extension, the term "step" has increasingly come to be associated with the space leader process itself. Should this emerging association, "step" = space leader attachment, be canonized? If not, then it seems reasonable to use the term "step" to describe impulsive positive leader extension. If, however, we do wish to associate the

  18. Improved perovskite phototransistor prepared using multi-step annealing method

    Science.gov (United States)

    Cao, Mingxuan; Zhang, Yating; Yu, Yu; Yao, Jianquan

    2018-02-01

    Organic-inorganic hybrid perovskites with good intrinsic physical properties have received substantial interest for solar cell and optoelectronic applications. However, perovskite film always suffers from a low carrier mobility due to its structural imperfection including sharp grain boundaries and pinholes, restricting their device performance and application potential. Here we demonstrate a straightforward strategy based on multi-step annealing process to improve the performance of perovskite photodetector. Annealing temperature and duration greatly affects the surface morphology and optoelectrical properties of perovskites which determines the device property of phototransistor. The perovskite films treated with multi-step annealing method tend to form highly uniform, well-crystallized and high surface coverage perovskite film, which exhibit stronger ultraviolet-visible absorption and photoluminescence spectrum compare to the perovskites prepared by conventional one-step annealing process. The field-effect mobilities of perovskite photodetector treated by one-step direct annealing method shows mobility as 0.121 (0.062) cm2V-1s-1 for holes (electrons), which increases to 1.01 (0.54) cm2V-1s-1 for that treated with muti-step slow annealing method. Moreover, the perovskite phototransistors exhibit a fast photoresponse speed of 78 μs. In general, this work focuses on the influence of annealing methods on perovskite phototransistor, instead of obtains best parameters of it. These findings prove that Multi-step annealing methods is feasible to prepared high performance based photodetector.

  19. Perceived need for restrictions on activity for children with epilepsy.

    Science.gov (United States)

    Brna, Paula M; Gordon, Kevin E; Woolridge, Elaine; Dooley, Joseph M; Wood, Ellen

    2017-08-01

    Children and youth with epilepsy have long been subjected to excessive restrictions on extracurricular activities due to concerns over risk of injury. Over time physicians and medical regulatory associations have liberalized the advice given for people with epilepsy to promote independence, self-esteem and general health benefits of physical activity. Current evidence suggests that few restrictions are needed for children with epilepsy beyond water-related precautions and avoidance of very high-risk activities. However, more stringent restrictions on daily activities may be imposed by caregivers. This study was aimed at exploring current perceptions of parents regarding restrictions on activity for children with epilepsy and the child's perspective on restrictions related to the diagnosis. A self-administered questionnaire was offered to a sample of parent-child dyads of children/youth with epilepsy attending summer camp for children with epilepsy age 8-18years. A 10-item validated HARCES Parent Scale of Childhood Epilepsy was completed by the parent/guardian and a modified-HARCES completed by the child. The primary objective was to assess the degree of restrictions placed on children with epilepsy from the perspective of child and parent assessed independently. Agreement of perceived restrictions between parent-child dyads was also determined. 21 parent/guardian-child pairs were recruited with mean age of children/youth 12.7years (range 9-16years). Total HARCES scores for parents and guardians ranged from 11-26 (x=16.5; SD 4.9) while total scores for children with epilepsy similarly ranged from 10-25 (x=15.2; SD 4.9). There were no differences in total parent scores when analyzed by child's age (13years), gender, age of seizure onset, seizure frequency or seizure type. Total HARCES scores showed no agreement between parent and child pairs with correlation of 0.2798 (95% CI -0.173-0.635). Children and youth with epilepsy often face activity restrictions based on

  20. Nonmedical Uses of Antibiotics: Time to Restrict Their Use?

    Science.gov (United States)

    Meek, Richard William; Vyas, Hrushi; Piddock, Laura Jane Violet

    2015-10-01

    The global crisis of antibiotic resistance has reached a point where, if action is not taken, human medicine will enter a postantibiotic world and simple injuries could once again be life threatening. New antibiotics are needed urgently, but better use of existing agents is just as important. More appropriate use of antibiotics in medicine is vital, but the extensive use of antibiotics outside medical settings is often overlooked. Antibiotics are commonly used in animal husbandry, bee-keeping, fish farming and other forms of aquaculture, ethanol production, horticulture, antifouling paints, food preservation, and domestically. This provides multiple opportunities for the selection and spread of antibiotic-resistant bacteria. Given the current crisis, it is vital that the nonmedical use of antibiotics is critically examined and that any nonessential use halted.

  1. Nonmedical Uses of Antibiotics: Time to Restrict Their Use?

    Directory of Open Access Journals (Sweden)

    Richard William Meek

    2015-10-01

    Full Text Available The global crisis of antibiotic resistance has reached a point where, if action is not taken, human medicine will enter a postantibiotic world and simple injuries could once again be life threatening. New antibiotics are needed urgently, but better use of existing agents is just as important. More appropriate use of antibiotics in medicine is vital, but the extensive use of antibiotics outside medical settings is often overlooked. Antibiotics are commonly used in animal husbandry, bee-keeping, fish farming and other forms of aquaculture, ethanol production, horticulture, antifouling paints, food preservation, and domestically. This provides multiple opportunities for the selection and spread of antibiotic-resistant bacteria. Given the current crisis, it is vital that the nonmedical use of antibiotics is critically examined and that any nonessential use halted.

  2. The Service-Time Restricted Capacitated Arc Routing Problem

    DEFF Research Database (Denmark)

    Lystlund, Lise; Wøhlk, Sanne

    We consider an inventory system, operated by a base stock policy and serving two customer classes. One customer class, Class 1, does not provide any advance demand information at all, while the other, Class 2, does. In order to reward a customer of Class 2 for providing advance order information......, it may be sensible to make reservations for the order in the inventory system, thereby preventing later arriving orders from getting access to the inventory before this particular order. We propose various reservation policies and study their impact on the performance of the inventory system....

  3. Quantitative feed restriction of Pekin breeder ducks during the ...

    African Journals Online (AJOL)

    hatchability of incubated duck eggs owing to restricted feed intake. ... Egg numbers, infertile eggs, fertile eggs, dead embryos, and duck- lings hatched were recorded for each of the 12 pens. At the same time as the six male and 24 female ducks were ..... treatment but thereafter there was a drop, even lower than the.

  4. Stability analysis of nonlinear systems with slope restricted nonlinearities.

    Science.gov (United States)

    Liu, Xian; Du, Jiajia; Gao, Qing

    2014-01-01

    The problem of absolute stability of Lur'e systems with sector and slope restricted nonlinearities is revisited. Novel time-domain and frequency-domain criteria are established by using the Lyapunov method and the well-known Kalman-Yakubovich-Popov (KYP) lemma. The criteria strengthen some existing results. Simulations are given to illustrate the efficiency of the results.

  5. Stability Analysis of Nonlinear Systems with Slope Restricted Nonlinearities

    Directory of Open Access Journals (Sweden)

    Xian Liu

    2014-01-01

    Full Text Available The problem of absolute stability of Lur’e systems with sector and slope restricted nonlinearities is revisited. Novel time-domain and frequency-domain criteria are established by using the Lyapunov method and the well-known Kalman-Yakubovich-Popov (KYP lemma. The criteria strengthen some existing results. Simulations are given to illustrate the efficiency of the results.

  6. 77 FR 65840 - Chrysanthemum White Rust Regulatory Status and Restrictions

    Science.gov (United States)

    2012-10-31

    ... Regulatory Status and Restrictions AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION: Advance... for our advance notice of proposed rulemaking that solicits public comment on whether and how we... importation of plant material that is a host of CWR. This action will allow interested persons additional time...

  7. Intrauterine growth restriction - part 2.

    Science.gov (United States)

    Sharma, Deepak; Farahbakhsh, Nazanin; Shastri, Sweta; Sharma, Pradeep

    2016-12-01

    Small for gestational age (SGA) infants have been classically defined as having birth weight less than two standard deviations below the mean or less than the 10th percentile of a population-specific birth weight for specific gestational age, whereas intrauterine growth restriction (IUGR) has been defined as a rate of foetal growth that is less than normal for the population and for the growth potential of a specific infant. SGA infants have more frequent problems such as perinatal asphyxia, hypothermia, hypoglycaemia, polycythaemia and many more when compared with their appropriate for gestational age counterpart. They too have growth retardation and various major and subtle neurodevelopmental handicaps, with higher rates of perinatal and neonatal mortality. With the advent of newer technologies, even though the perinatal diagnosis of these SGA/IUGR foetuses has increased, but still perinatal morbidity and mortality rates are higher than normal foetuses and infants. In this part, we have covered neonatal IUGR classification, postnatal diagnosis, short-term and long-term complications faced by these IUGR infants.

  8. Placental Adaptations in Growth Restriction

    Science.gov (United States)

    Zhang, Song; Regnault, Timothy R.H.; Barker, Paige L.; Botting, Kimberley J.; McMillen, Isabella C.; McMillan, Christine M.; Roberts, Claire T.; Morrison, Janna L.

    2015-01-01

    The placenta is the primary interface between the fetus and mother and plays an important role in maintaining fetal development and growth by facilitating the transfer of substrates and participating in modulating the maternal immune response to prevent immunological rejection of the conceptus. The major substrates required for fetal growth include oxygen, glucose, amino acids and fatty acids, and their transport processes depend on morphological characteristics of the placenta, such as placental size, morphology, blood flow and vascularity. Other factors including insulin-like growth factors, apoptosis, autophagy and glucocorticoid exposure also affect placental growth and substrate transport capacity. Intrauterine growth restriction (IUGR) is often a consequence of insufficiency, and is associated with a high incidence of perinatal morbidity and mortality, as well as increased risk of cardiovascular and metabolic diseases in later life. Several different experimental methods have been used to induce placental insufficiency and IUGR in animal models and a range of factors that regulate placental growth and substrate transport capacity have been demonstrated. While no model system completely recapitulates human IUGR, these animal models allow us to carefully dissect cellular and molecular mechanisms to improve our understanding and facilitate development of therapeutic interventions. PMID:25580812

  9. Cardiac MRI in restrictive cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, A. [Department of Cardiovascular Radiology, All India Institute of Medical Sciences, Ansari Nagar, Delhi (India); Singh Gulati, G., E-mail: gulatigurpreet@rediffmail.com [Department of Cardiovascular Radiology, All India Institute of Medical Sciences, Ansari Nagar, Delhi (India); Seth, S. [Department of Cardiology, All India Institute of Medical Sciences, Ansari Nagar, Delhi (India); Sharma, S. [Department of Cardiovascular Radiology, All India Institute of Medical Sciences, Ansari Nagar, Delhi (India)

    2012-02-15

    Restrictive cardiomyopathy (RCM) is a specific group of heart muscle disorders characterized by inadequate ventricular relaxation during diastole. This leads to diastolic dysfunction with relative preservation of systolic function. Although short axis systolic function is usually preserved in RCM, the long axis systolic function may be severely impaired. Confirmation of diagnosis and information regarding aetiology, extent of myocardial damage, and response to treatment requires imaging. Importantly, differentiation from constrictive pericarditis (CCP) is needed, as only the latter is managed surgically. Echocardiography is the initial cardiac imaging technique but cannot reliably suggest a tissue diagnosis; although recent advances, especially tissue Doppler imaging and spectral tracking, have improved its ability to differentiate RCM from CCP. Cardiac catheterization is the reference standard, but is invasive, two-dimensional, and does not aid myocardial characterization. Cardiac magnetic resonance (CMR) is a versatile technique providing anatomical, morphological and functional information. In recent years, it has been shown to provide important information regarding disease mechanisms, and also been found useful to guide treatment, assess its outcome and predict patient prognosis. This review describes the CMR features of RCM, appearances in various diseases, its overall role in patient management, and how it compares with other imaging techniques.

  10. Alteration of placental haemostatic mechanisms in idiopathic intrauterine growth restriction

    Directory of Open Access Journals (Sweden)

    Jaime Eduardo Bernal Villegas

    2012-08-01

    Full Text Available Intrauterine growth restriction is a complication of pregnancy with a high probability of perinatal morbidity and mortality. It appears tobe caused by abnormal development of placental vasculature. Haemostatic processes are important for the development of the placenta,and an imbalance between procoagulant and anticoagulant factors has been associated with risk of intrauterine growth restriction.Objective. To evaluate coagulation abnormalities in placenta of pregnancies complicated with idiopathic intrauterine growth restriction.Materials and methods. Five placentas from pregnancies with idiopathic intrauterine growth restriction were compared to 19 controls.We performed gross and histological examination of the placenta. Analysis was made of both mRNA expression by real-time PCRand protein by ELISA of tissue factor and thrombomodulin in placental tissue. Results. Results based on histological evaluation wereconsistent with an increased prothrombotic state in placentas from pregnancies with idiopathic intrauterine growth restriction, andthrombosis of chorionic vessels was the most important finding. The study showed an increased expression of tissue factor protein(p=0.0411 and an increase in the ratio of tissue factor/thrombomodulin mRNA (p=0.0411 and protein (p=0.0215 in placentas frompregnancies with idiopathic intrauterine growth restriction. There were no statistically significant differences neither between cases andcontrols in the mRNA levels of tissue factor or thrombomodulin nor at the protein level of thrombomodulin. Conclusion. Evidence ofalteration of local haemostatic mechanisms at the level of the placenta, including abnormal expression of tissue factor and tissue factor/thrombomodulin ratio, in pregnancies that occur with idiopathic intrauterine growth restriction is presented.

  11. Microsoft® Office Access™ 2007 Step by Step

    CERN Document Server

    Lambert, Steve; Lambert, Joan

    2009-01-01

    Experience learning made easy-and quickly teach yourself how to build database solutions with Access 2007. With Step By Step, you set the pace-building and practicing the skills you need, just when you need them! Build databases from scratch or from templatesExchange data with other databases and Office documentsCreate forms to simplify data entryUse filters and queries to find and analyze informationDesign rich reports that help make your data meaningfulHelp prevent data corruption and unauthorized access Your all-in-one learning experience includes: Files for building skills and practic

  12. Microsoft Windows Sharepoint Services 3.0 Step by Step

    CERN Document Server

    Londer, Olga; Bleeker, Todd; Coventry, Penelope

    2007-01-01

    Experience learning made easy-and quickly teach yourself how to use Windows SharePoint Services to enable effective team collaboration. With Step By Step, you set the pace-building and practicing the skills you need, just when you need them! Build your own SharePoint site with easy-to-use templatesCreate lists and libraries to store informationAdd discussion boards, wikis, and blogsSet up Document and Meeting Workspaces for easy collaborationShare calendars, contacts, and data from Microsoft Office programsCustomize your pages with Web Parts Your all-in-one learning experience includes: Fi

  13. Linear, Step by Step Managerial Performance, versus Exponential Performance

    Directory of Open Access Journals (Sweden)

    George MOLDOVEANU

    2011-04-01

    Full Text Available The paper proposes the transition from the potential management concept, which its authors approached by determining its dimension (Roşca, Moldoveanu, 2009b, to the linear, step by step performance concept, as an objective result of management process. In this way, we “answer” the theorists and practitioners, who support exponential management performance. The authors, as detractors of the exponential performance, are influenced by the current crisis (Roşca, Moldoveanu, 2009a, by the lack of organizational excellence in many companies, particularly in Romanian ones and also reaching “the finality” in the evolved companies, developed into an uncontrollable speed.

  14. A step-by-step methodology for enterprise interoperability projects

    Science.gov (United States)

    Chalmeta, Ricardo; Pazos, Verónica

    2015-05-01

    Enterprise interoperability is one of the key factors for enhancing enterprise competitiveness. Achieving enterprise interoperability is an extremely complex process which involves different technological, human and organisational elements. In this paper we present a framework to help enterprise interoperability. The framework has been developed taking into account the three domains of interoperability: Enterprise Modelling, Architecture and Platform and Ontologies. The main novelty of the framework in comparison to existing ones is that it includes a step-by-step methodology that explains how to carry out an enterprise interoperability project taking into account different interoperability views, like business, process, human resources, technology, knowledge and semantics.

  15. One step beyond: Different step-to-step transitions exist during continuous contact brachiation in siamangs

    Directory of Open Access Journals (Sweden)

    Fana Michilsens

    2012-02-01

    In brachiation, two main gaits are distinguished, ricochetal brachiation and continuous contact brachiation. During ricochetal brachiation, a flight phase exists and the body centre of mass (bCOM describes a parabolic trajectory. For continuous contact brachiation, where at least one hand is always in contact with the substrate, we showed in an earlier paper that four step-to-step transition types occur. We referred to these as a ‘point’, a ‘loop’, a ‘backward pendulum’ and a ‘parabolic’ transition. Only the first two transition types have previously been mentioned in the existing literature on gibbon brachiation. In the current study, we used three-dimensional video and force analysis to describe and characterize these four step-to-step transition types. Results show that, although individual preference occurs, the brachiation strides characterized by each transition type are mainly associated with speed. Yet, these four transitions seem to form a continuum rather than four distinct types. Energy recovery and collision fraction are used as estimators of mechanical efficiency of brachiation and, remarkably, these parameters do not differ between strides with different transition types. All strides show high energy recoveries (mean  = 70±11.4% and low collision fractions (mean  = 0.2±0.13, regardless of the step-to-step transition type used. We conclude that siamangs have efficient means of modifying locomotor speed during continuous contact brachiation by choosing particular step-to-step transition types, which all minimize collision fraction and enhance energy recovery.

  16. Restriction genes for retroviruses influence the risk of multiple sclerosis

    DEFF Research Database (Denmark)

    Nexø, Bjørn A; Hansen, Bettina; Nissen, Kari K

    2013-01-01

    known for a long time. Today human restriction genes for retroviruses include amongst others TRIMs, APOBEC3s, BST2 and TREXs. We have therefore looked for a role of these retroviral restriction genes in MS using genetic epidemiology. We here report that markers in two TRIMs, TRIM5 and TRIM22...... and a marker in BST2, associated statistically with the risk of getting MS, while markers in or near APOBEC3s and TREXs showed little or no effect. This indicates that the two TRIMs and BST2 influence the risk of disease and thus supports the hypothesis of a viral involvement....

  17. Tandem mirror next step: remote maintenance

    International Nuclear Information System (INIS)

    Doggett, J.N.; Damm, C.C.; Hanson, C.L.

    1980-01-01

    This study of the next proposed experiment in the Mirror Fusion Program, the Tandem Mirror Next Step (TMNS), has included serious consideration of the maintenance requirements of such a large source of high energy neutrons with its attendant throughput of tritium. Although maintenance will be costly in time and money, our conclusion is that with careful attention to a design for maintenance plan such a device can be reliably operated

  18. High accuracy step gauge interferometer

    Science.gov (United States)

    Byman, V.; Jaakkola, T.; Palosuo, I.; Lassila, A.

    2018-05-01

    Step gauges are convenient transfer standards for the calibration of coordinate measuring machines. A novel interferometer for step gauge calibrations implemented at VTT MIKES is described. The four-pass interferometer follows Abbe’s principle and measures the position of the inductive probe attached to a measuring head. The measuring head of the instrument is connected to a balanced boom above the carriage by a piezo translation stage. A key part of the measuring head is an invar structure on which the inductive probe and the corner cubes of the measuring arm of the interferometer are attached. The invar structure can be elevated so that the probe is raised without breaking the laser beam. During probing, the bending of the probe and the interferometer readings are recorded and the measurement face position is extrapolated to zero force. The measurement process is fully automated and the face positions of the steps can be measured up to a length of 2 m. Ambient conditions are measured continuously and the refractive index of air is compensated for. Before measurements the step gauge is aligned with an integrated 2D coordinate measuring system. The expanded uncertainty of step gauge calibration is U=\\sqrt{{{(64 nm)}2}+{{(88× {{10}-9}L)}2}} .

  19. FIRST STEP towards ICF commercialization

    International Nuclear Information System (INIS)

    Saylor, W.W.; Pendergrass, J.H.; Dudziak, D.J.

    1984-01-01

    Production of tritium for weapons and fusion R and D programs and successful development of Inertial Confinement Fusion (ICF) technologies are important national goals. A conceptual design for an ICF facility to meet these goals is presented. FIRST STEP (Fusion, Inertial, Reduced-Requirements Systems Test for Special Nuclear Material, Tritium, and Energy Production) is a concept for a plant to produce SNM, tritium, and energy while serving as a test bed for ICF technology development. A credible conceptual design for an ICF SNM and tritium production facility that competes favorably with fission technology on the bases of cost, production quality, and safety was sought. FIRST STEP is also designed to be an engineering test facility that integrates systems required for an ICF power plant and that is intermediate in scale between proof-of-principle experiment and commercial power plant. FIRST STEP driver and pellet performance requirements are moderate and represent reasonable intermediate goals in an R and D plan for ICF commercialization. Repetition rate requirements for FIRST STEP are similar to those of commercial size plants and FIRST STEP can be used to integrate systems under realistic ICF conditions

  20. Curves of restricted type in euclidean spaces

    Directory of Open Access Journals (Sweden)

    Bengü Kılıç Bayram

    2014-01-01

    Full Text Available Submanifolds of restricted type were introduced in [7]. In the present study we consider restricted type of curves in Em. We give some special examples. We also show that spherical curve in S2(r C E3 is of restricted type if and only if either ƒ(s is constant or a linear function of s of the form ƒ(s = ±s + b and every closed W - curve of rank k and of length 2(r in E2k is of restricted type.

  1. From raw material to dish: pasta quality step by step.

    Science.gov (United States)

    Sicignano, Angelo; Di Monaco, Rossella; Masi, Paolo; Cavella, Silvana

    2015-10-01

    Pasta is a traditional Italian cereal-based food that is popular worldwide because of its convenience, versatility, sensory and nutritional value. The aim of this review is to present a step-by-step guide to facilitate the understanding of the most important events that can affect pasta characteristics, directing the reader to the appropriate production steps. Owing to its unique flavor, color, composition and rheological properties, durum wheat semolina is the best raw material for pasta production. Although pasta is traditionally made from only two ingredients, sensory quality and chemical/physical characteristics of the final product may vary greatly. Starting from the same ingredients, there are a lot of different events in each step of pasta production that can result in the development of varieties of pasta with different characteristics. In particular, numerous studies have demonstrated the importance of temperature and humidity conditions of the pasta drying operation as well as the significance of the choice of raw material and operating conditions on pasta quality. © 2015 Society of Chemical Industry.

  2. Step-by-step phacoemulsification training program for ophthalmology residents

    Directory of Open Access Journals (Sweden)

    Wang Yulan

    2013-01-01

    Full Text Available Aims: The aim was to analyze the learning curve of phacoemulsification (phaco performed by residents without experience in performing extra-capsular cataract extraction (ECCE in a step-by-step training program (SBSTP. Materials and Methods: Consecutive surgical records of phaco performed from March 2009 to Sept 2011 by four residents without previous ECCE experience were retrospectively reviewed. The completion rate of the first 30 procedures by each resident was calculated. The main intraoperative phaco parameter records for the first 30 surgeries by each resident were compared with those for their last 30 surgeries. Intraoperative complications in the residents′ procedures were also recorded and analyzed. Results: A total of 1013 surgeries were performed by residents. The completion rate for the first 30 phaco procedures was 79.2 μ 5.8%. The main reasons for halting the procedure were as follows: Anterior capsule tear, inability to crack the nucleus, and posterior capsular rupture during phaco or cortex removal. Cumulative dissipated energy of phaco power used during the surgeries was significantly less in the last 30 cases compared with the first 30 cases (30.10 μ 17.58 vs. 55.41 μ 37.59, P = 0.021. Posterior capsular rupture rate was 2.5 μ 1.2% in total (10.8 μ 4.2% in the first 30 cases and 1.7 μ 1.9% in the last 30 cases, P = 0.008; a statistically significant difference. Conclusion:The step-by-step training program might be a necessary process for a resident to transit from dependence to a self-supported operator. It is also an essential middle step between wet lab training to performing the entire phaco procedure on the patient both effectively and safely.

  3. A mechanism for leader stepping

    Science.gov (United States)

    Ebert, U.; Carlson, B. E.; Koehn, C.

    2013-12-01

    The stepping of negative leaders is well observed, but not well understood. A major problem consists of the fact that the streamer corona is typically invisible within a thunderstorm, but determines the evolution of a leader. Motivated by recent observations of streamer and leader formation in the laboratory by T.M.P. Briels, S. Nijdam, P. Kochkin, A.P.J. van Deursen et al., by recent simulations of these processes by J. Teunissen, A. Sun et al., and by our theoretical understanding of the process, we suggest how laboratory phenomena can be extrapolated to lightning leaders to explain the stepping mechanism.

  4. It just doesn't speak to me: mid-aged men's reactions to '10,000 Steps a Day'.

    Science.gov (United States)

    Burton, Nicola W; Walsh, Anthony; Brown, Wendy J

    2008-04-01

    The evaluation of an earlier 10,000 Steps community-based intervention program indicated that men were less likely than women to have used a pedometer or increased their physical activity (PA). This study aimed to explore men's reactions to the 10,000 Steps a Day message, the use of pedometers, and other strategies for increasing PA. Five focus groups were conducted with 39 men aged 45-65 years. Although many were familiar with the 10,000 Steps message, the majority of men did not like it. Pedometers were seen as useful for assessing PA in the short term, but not for ongoing use. Participants were generally aware of PA recommendations. Walking was considered a good option for this age group, but there was varying interest in this type of activity. Weight and stress management were commonly identified benefits of PA. Common barriers to PA were lack of time and motivation, health and weight restrictions, cost, and disinterest. Suggestions of how to promote PA to mid-aged men included workplace initiatives, making PA "fun", and creating opportunities for men to do PA with their family or same-aged peers. PA promotion using the 10,000 Steps message, walking, and pedometers may not appeal to mid-aged men.

  5. Hirsutine, an Indole Alkaloid of Uncaria rhynchophylla, Inhibits Late Step in Dengue Virus Lifecycle

    Directory of Open Access Journals (Sweden)

    Takayuki Hishiki

    2017-08-01

    Full Text Available Dengue virus (DENV is transmitted to humans by Aedes mosquitoes and is a public health issue worldwide. No antiviral drugs specific for treating dengue infection are currently available. To identify novel DENV inhibitors, we analyzed a library of 95 compounds and 120 extracts derived from crude drugs (herbal medicines. In the primary screening, A549 cells infected with DENV-1 were cultured in the presence of each compound and extract at a final concentration of 10 μM (compound and 100 μg/mL (extract, and reduction of viral focus formation was assessed. Next, we eliminated compounds and extracts which were cytotoxic using the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide assay. Hirsutine, an indole alkaloid of Uncaria rhynchophylla, was identified as a potent anti-DENV compound exhibiting high efficacy and low cytotoxicity. Hirsutine showed antiviral activity against all DENV serotypes. Time-of-drug-addition and time-of-drug-elimination assays indicated that hirsutine inhibits the viral particle assembly, budding, or release step but not the viral translation and replication steps in the DENV lifecycle. A subgenomic replicon system was used to confirm that hirsutine does not restrict viral genome RNA replication. Hirsutine is a novel DENV inhibitor and potential candidate for treating dengue fever.

  6. Hirsutine, an Indole Alkaloid of Uncaria rhynchophylla, Inhibits Late Step in Dengue Virus Lifecycle.

    Science.gov (United States)

    Hishiki, Takayuki; Kato, Fumihiro; Tajima, Shigeru; Toume, Kazufumi; Umezaki, Masahito; Takasaki, Tomohiko; Miura, Tomoyuki

    2017-01-01

    Dengue virus (DENV) is transmitted to humans by Aedes mosquitoes and is a public health issue worldwide. No antiviral drugs specific for treating dengue infection are currently available. To identify novel DENV inhibitors, we analyzed a library of 95 compounds and 120 extracts derived from crude drugs (herbal medicines). In the primary screening, A549 cells infected with DENV-1 were cultured in the presence of each compound and extract at a final concentration of 10 μM (compound) and 100 μg/mL (extract), and reduction of viral focus formation was assessed. Next, we eliminated compounds and extracts which were cytotoxic using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Hirsutine, an indole alkaloid of Uncaria rhynchophylla , was identified as a potent anti-DENV compound exhibiting high efficacy and low cytotoxicity. Hirsutine showed antiviral activity against all DENV serotypes. Time-of-drug-addition and time-of-drug-elimination assays indicated that hirsutine inhibits the viral particle assembly, budding, or release step but not the viral translation and replication steps in the DENV lifecycle. A subgenomic replicon system was used to confirm that hirsutine does not restrict viral genome RNA replication. Hirsutine is a novel DENV inhibitor and potential candidate for treating dengue fever.

  7. Improving computer security for authentication of users: influence of proactive password restrictions.

    Science.gov (United States)

    Proctor, Robert W; Lien, Mei-Ching; Vu, Kim-Phuong L; Schultz, E Eugene; Salvendy, Gavriel

    2002-05-01

    Entering a username-password combination is a widely used procedure for identification and authentication in computer systems. However, it is a notoriously weak method, in that the passwords adopted by many users are easy to crack. In an attempt to improve security, proactive password checking may be used, in which passwords must meet several criteria to be more resistant to cracking. In two experiments, we examined the influence of proactive password restrictions on the time that it took to generate an acceptable password and to use it subsequently to long in. The required length was a minimum of five characters in Experiment 1 and eight characters in Experiment 2. In both experiments, one condition had only the length restriction, and the other had additional restrictions. The additional restrictions greatly increased the time it took to generate the password but had only a small effect on the time it took to use it subsequently to long in. For the five-character passwords, 75% were cracked when no other restrictions were imposed, and this was reduced to 33% with the additional restrictions. For the eight-character passwords, 17% were cracked with no other restrictions, and 12.5% with restrictions. The results indicate that increasing the minimum character length reduces crackability and increases security, regardless of whether additional restrictions are imposed.

  8. Ten steps to successful poster presentation.

    Science.gov (United States)

    Hardicre, Jayne; Devitt, Patric; Coad, Jane

    Receiving a letter confirming acceptance for you to present a poster at a conference can evoke mixed emotions. Joy, panic, fear and dread are among the many possible emotions and this is not exclusive to first time presenters. Developing an effective poster presentation is a skill that you can learn and can provide a rewarding way to present your work in a manner less intimidating than oral presentation (Shelledy, 2004). The key to successful poster presentation is meticulous, timely, well informed preparation. This article outlines ten steps to help guide you through the process to maximize your success.

  9. The elementary steps of the photodissociation and recombination reactions of iodine molecules enclosed in cages and channels of zeolite crystals: A femtosecond time-resolved study of the geometry effect

    International Nuclear Information System (INIS)

    Flachenecker, G.; Materny, A.

    2004-01-01

    We present femtosecond time-resolved pump-probe experiments on iodine molecules enclosed into well-defined cages and channels of different crystalline SiO 2 modifications of zeolites. The new experimental results obtained from iodine in TON (Silica-ZSM-22), FER (Silica-Ferrierit), and MFI (Silicalit-1) porosils are compared with data published earlier on the iodine/DDR (Decadodecasil 3R) porosil system [Flachenecker et al., Phys. Chem. Chem. Phys. 5, 865 (2003)]. A summary of all findings is given. The processes analyzed by means of the ultrafast spectroscopy are the vibrational relaxation as well as the dissociation and recombination reactions, which are caused by the interaction of the photo-excited iodine molecules with the cavity walls of the porosils. A clear dependence of the observed dynamics on the geometry of the surrounding lattice structure can be seen. These measurements are supported by temperature-dependent experiments. Making use of a theoretical model which is based on the classical Langevin equation, an analysis of the geometry-reaction relation is performed. The Brownian dynamics simulations show that in contrast to the vibrational relaxation the predissociation dynamics are independent of the frequency of collisions with the surroundings. From the results obtained in the different surroundings, we conclude that mainly local fields are responsible for the crossing from the bound B state to the repulsive a/a ' states of the iodine molecules

  10. Universal Cycles of Restricted Classes of Words

    OpenAIRE

    Leitner, Arielle; Godbole, Anant

    2008-01-01

    It is well known that Universal Cycles of $k$-letter words on an $n$-letter alphabet exist for all $k$ and $n$. In this paper, we prove that Universal Cycles exist for restricted classes of words, including: non-bijections, equitable words (under suitable restrictions), ranked permutations, and "passwords".

  11. Freedom and Restrictions in Language Use.

    Science.gov (United States)

    O'Donnell, Roy C.

    Since freedom of thought and expression is essential in a democracy, censorship of language is rightly regarded as a threat to all other freedoms. Still, it is inevitable that certain restrictions will occasionally be imposed on language in America and in other societies. Restrictions on language date back to the Ten Commandments, which condemned…

  12. Protein restriction in chronic renal failure

    NARCIS (Netherlands)

    ECHTEN, JEKT; NAUTA, J; HOP, WCJ; de Jong, MCJ; REITSMABIERENS, WCC; VANAMSTEL, SLBP; VANACKER, KJ; NOORDZIJ, CM; WOLFF, ED

    The aim of the study was to investigate the effect of a protein restricted diet on renal function and growth of children with chronic renal failure. In a multicentre prospective study 56 children (aged 2-18 years) with chronic renal failure were randomly assigned to the protein restricted (0.8-1.1

  13. Relationship Between Calorie Restriction, Lipid Peroxidation ...

    African Journals Online (AJOL)

    In the brain of the caloric restricted rats, there was little or no change in the tGSH and GSH, although the GSSG and GSSG/GSH% ratio were increased significantly. These results suggest that aging of rats had been decelerated by caloric restriction due to the decrease in the peroxidative damage in the lungs and brain.

  14. Eclampsia despite strict dietary sodium restriction.

    NARCIS (Netherlands)

    Delemarre, F.M.C.; Steegers, E.A.P.; Berendes, J.N.

    2001-01-01

    The classic indication for prescribing dietary sodium restriction in pregnancy has been the prevention of eclampsia. We describe a case of intrapartum eclampsia in a 24-year-old nulliparous woman. A strongly sodium restricted diet was prescribed because of pre-eclampsia. Compliance to the diet was

  15. 7 CFR 3430.205 - Funding restrictions.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Funding restrictions. 3430.205 Section 3430.205... Funding restrictions. (a) Prohibition against construction. Funds made available under this subpart shall not be used for the construction of a new building or facility or the acquisition, expansion...

  16. 28 CFR 804.3 - Restrictions.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Restrictions. 804.3 Section 804.3 Judicial Administration COURT SERVICES AND OFFENDER SUPERVISION AGENCY FOR THE DISTRICT OF COLUMBIA ACCEPTANCE OF GIFTS § 804.3 Restrictions. (a) The Agency is not authorized to accept gifts of money, stock...

  17. Driver training in steps (DTS).

    NARCIS (Netherlands)

    2010-01-01

    For some years now, it has been possible in the Netherlands to follow a Driver Training in Steps (DTS) as well as the regular driver training. The DTS is a structured training method with clear training objectives which are categorized in four modules. Although the DTS is considerably better than

  18. Ultra-structural time-course study in the C. elegans model for Duchenne muscular dystrophy highlights a crucial role for sarcomere-anchoring structures and sarcolemma integrity in the earliest steps of the muscle degeneration process.

    Science.gov (United States)

    Brouilly, Nicolas; Lecroisey, Claire; Martin, Edwige; Pierson, Laura; Mariol, Marie-Christine; Qadota, Hiroshi; Labouesse, Michel; Streichenberger, Nathalie; Mounier, Nicole; Gieseler, Kathrin

    2015-11-15

    Duchenne muscular dystrophy (DMD) is a genetic disease characterized by progressive muscle degeneration due to mutations in the dystrophin gene. In spite of great advances in the design of curative treatments, most patients currently receive palliative therapies with steroid molecules such as prednisone or deflazacort thought to act through their immunosuppressive properties. These molecules only slightly slow down the progression of the disease and lead to severe side effects. Fundamental research is still needed to reveal the mechanisms involved in the disease that could be exploited as therapeutic targets. By studying a Caenorhabditis elegans model for DMD, we show here that dystrophin-dependent muscle degeneration is likely to be cell autonomous and affects the muscle cells the most involved in locomotion. We demonstrate that muscle degeneration is dependent on exercise and force production. Exhaustive studies by electron microscopy allowed establishing for the first time the chronology of subcellular events occurring during the entire process of muscle degeneration. This chronology highlighted the crucial role for dystrophin in stabilizing sarcomeric anchoring structures and the sarcolemma. Our results suggest that the disruption of sarcomeric anchoring structures and sarcolemma integrity, observed at the onset of the muscle degeneration process, triggers subcellular consequences that lead to muscle cell death. An ultra-structural analysis of muscle biopsies from DMD patients suggested that the chronology of subcellular events established in C. elegans models the pathogenesis in human. Finally, we found that the loss of sarcolemma integrity was greatly reduced after prednisone treatment suggesting a role for this molecule in plasma membrane stabilization. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Development of single-step multiplex real-time RT-PCR assays for rapid diagnosis of enterovirus 71, coxsackievirus A6, and A16 in patients with hand, foot, and mouth disease.

    Science.gov (United States)

    Puenpa, Jiratchaya; Suwannakarn, Kamol; Chansaenroj, Jira; Vongpunsawad, Sompong; Poovorawan, Yong

    2017-10-01

    Real-time reverse-transcription polymerase chain reaction (rRT-PCR) to detect enterovirus 71 (EV-A71) and coxsackievirus A16 (CV-A16) has facilitated the rapid and accurate identification of the two most common etiological agents underlying hand, foot, and mouth disease (HFMD). However, the worldwide emergence of CV-A6 infection in HFMD necessitates development of an improved multiplex rRT-PCR method. To rapidly determine the etiology of HFMD, two rRT-PCR assays using TaqMan probes were developed to differentiate among three selected common enteroviruses (EV-A71, CV-A16 and CV-A6) and to enable broad detection of enteroviruses (pan-enterovirus assay). No cross-reactions were observed with other RNA viruses examined. The detection limits of both assays were 10 copies per microliter for EV-A71, CV-A6 and CV-A16, and pan-enterovirus. The methods showed high accuracy (EV-A71, 90.6%; CV-A6, 92.0%; CV-A16, 100%), sensitivity (EV-A71, 96.5%; CV-A6, 95.8%; CV-A16, 99.0%), and specificity (EV-A71, 100%; CV-A6, 99.9%; CV-A16, 99.9%) in testing clinical specimens (n=1049) during 2014-2016, superior to those of conventional RT-PCR. Overall, the multiplex rRT-PCR assays enabled highly sensitive detection and rapid simultaneous typing of EV-A71, CV-A6 and CV-A16, and enteroviruses, rendering them feasible and attractive methods for large-scale surveillance of enteroviruses associated with HFMD outbreaks. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Strengthening implant provision and acceptance in South Africa with the ‘Any woman any place any time’ approach: An essential step towards reducing unintended pregnancies

    Directory of Open Access Journals (Sweden)

    H Rees

    2017-11-01

    Full Text Available Progress in reducing unintended pregnancies in South Africa is slow. The implant, introduced in 2014, expanded the range of available longacting reversible contraceptives (LARCs and held much promise. Uptake, however, has declined precipitously, in spite of its ‘unmatched effectiveness’ and high levels of satisfaction for most users. We propose policy and provider interventions to raise implant use, underscored by a ‘LARC-first’ approach. Contraceptive counselling should focus on the particular benefits of LARCs and methods be presented in order of effectiveness. Moreover, implants hold particular advantages for certain groups, especially adolescents and young women, in whom it is considered first-line contraception. Provision of immediate postpartum and post-abortion implants is safe and highly acceptable, yet remains under-utilised. Implant services at HIV and tuberculosis clinics are a key priority, as is inclusion of LARC provision within school health services. Implants could also be delivered by existing mobile outreach services, for example in sex worker programmes. Services could be built around nurses dedicated solely to providing implants, with other health workers receiving brief refresher training. Women who experience side-effects, especially abnormal bleeding, require timely interventions, following a standardised protocol, including use of medications. Encouraging return for side-effects, follow-up phone calls and home visits would raise continuation rates. Removal services require doctor support or designated nurses at specific centres. Limited access to removal services, health workers’  resistance or botched procedures will further undermine implant provision. Rapid implant demonstration projects in postpartum wards, schools, outreach services and by dedicated providers may rapidly advance the field. Together, the actions outlined here will ensure that the implant fulfils its potential and